--- /dev/null
+eCryptfs: A stacked cryptographic filesystem for Linux
+
+eCryptfs is free software. Please see the file COPYING for details.
+For documentation, please see the files in the doc/ subdirectory. For
+building and installation instructions please see the INSTALL file.
+
+Maintainer: Phillip Hellewell
+Lead developer: Michael A. Halcrow <mhalcrow@us.ibm.com>
+Developers: Michael C. Thompson
+ Kent Yoder
+Web Site: http://ecryptfs.sf.net
+
+This software is currently undergoing development. Make sure to
+maintain a backup copy of any data you write into eCryptfs.
+
+eCryptfs requires the userspace tools downloadable from the
+SourceForge site:
+
+http://sourceforge.net/projects/ecryptfs/
+
+Userspace requirements include:
+ - David Howells' userspace keyring headers and libraries (version
+ 1.0 or higher), obtainable from
+ http://people.redhat.com/~dhowells/keyutils/
+ - Libgcrypt
+
+
+NOTES
+
+In the beta/experimental releases of eCryptfs, when you upgrade
+eCryptfs, you should copy the files to an unencrypted location and
+then copy the files back into the new eCryptfs mount to migrate the
+files.
+
+
+MOUNT-WIDE PASSPHRASE
+
+Create a new directory into which eCryptfs will write its encrypted
+files (i.e., /root/crypt). Then, create the mount point directory
+(i.e., /mnt/crypt). Now it's time to mount eCryptfs:
+
+mount -t ecryptfs /root/crypt /mnt/crypt
+
+You should be prompted for a passphrase and a salt (the salt may be
+blank).
+
+Try writing a new file:
+
+echo "Hello, World" > /mnt/crypt/hello.txt
+
+The operation will complete. Notice that there is a new file in
+/root/crypt that is at least 12288 bytes in size (depending on your
+host page size). This is the encrypted underlying file for what you
+just wrote. To test reading, from start to finish, you need to clear
+the user session keyring:
+
+keyctl clear @u
+
+Then umount /mnt/crypt and mount again per the instructions given
+above.
+
+cat /mnt/crypt/hello.txt
+
+
+NOTES
+
+eCryptfs version 0.1 should only be mounted on (1) empty directories
+or (2) directories containing files only created by eCryptfs. If you
+mount a directory that has pre-existing files not created by eCryptfs,
+then behavior is undefined. Do not run eCryptfs in higher verbosity
+levels unless you are doing so for the sole purpose of debugging or
+development, since secret values will be written out to the system log
+in that case.
+
+
+Mike Halcrow
+mhalcrow@us.ibm.com
W: http://ebtables.sourceforge.net/
S: Maintained
+ECRYPT FILE SYSTEM
+P: Mike Halcrow, Phillip Hellewell
+M: mhalcrow@us.ibm.com, phillip@hellewell.homeip.net
+L: ecryptfs-devel@lists.sourceforge.net
+W: http://ecryptfs.sourceforge.net/
+S: Supported
+
EDAC-CORE
P: Doug Thompson
M: norsk5@xmission.com
To compile this file system support as a module, choose M here: the
module will be called affs. If unsure, say N.
+config ECRYPT_FS
+ tristate "eCrypt filesystem layer support (EXPERIMENTAL)"
+ depends on EXPERIMENTAL && KEYS && CRYPTO
+ help
+ Encrypted filesystem that operates on the VFS layer. See
+ <file:Documentation/ecryptfs.txt> to learn more about
+ eCryptfs. Userspace components are required and can be
+ obtained from <http://ecryptfs.sf.net>.
+
+ To compile this file system support as a module, choose M here: the
+ module will be called ecryptfs.
+
config HFS_FS
tristate "Apple Macintosh file system support (EXPERIMENTAL)"
depends on BLOCK && EXPERIMENTAL
obj-$(CONFIG_ISO9660_FS) += isofs/
obj-$(CONFIG_HFSPLUS_FS) += hfsplus/ # Before hfs to find wrapped HFS+
obj-$(CONFIG_HFS_FS) += hfs/
+obj-$(CONFIG_ECRYPT_FS) += ecryptfs/
obj-$(CONFIG_VXFS_FS) += freevxfs/
obj-$(CONFIG_NFS_FS) += nfs/
obj-$(CONFIG_EXPORTFS) += exportfs/
--- /dev/null
+#
+# Makefile for the Linux 2.6 eCryptfs
+#
+
+obj-$(CONFIG_ECRYPT_FS) += ecryptfs.o
+
+ecryptfs-objs := dentry.o file.o inode.o main.o super.o mmap.o crypto.o keystore.o debug.o
--- /dev/null
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 1997-2004 Erez Zadok
+ * Copyright (C) 2001-2004 Stony Brook University
+ * Copyright (C) 2004-2006 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ * Michael C. Thompson <mcthomps@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/pagemap.h>
+#include <linux/random.h>
+#include <linux/compiler.h>
+#include <linux/key.h>
+#include <linux/namei.h>
+#include <linux/crypto.h>
+#include <linux/file.h>
+#include <linux/scatterlist.h>
+#include "ecryptfs_kernel.h"
+
+static int
+ecryptfs_decrypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat,
+ struct page *dst_page, int dst_offset,
+ struct page *src_page, int src_offset, int size,
+ unsigned char *iv);
+static int
+ecryptfs_encrypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat,
+ struct page *dst_page, int dst_offset,
+ struct page *src_page, int src_offset, int size,
+ unsigned char *iv);
+
+/**
+ * ecryptfs_to_hex
+ * @dst: Buffer to take hex character representation of contents of
+ * src; must be at least of size (src_size * 2)
+ * @src: Buffer to be converted to a hex string respresentation
+ * @src_size: number of bytes to convert
+ */
+void ecryptfs_to_hex(char *dst, char *src, size_t src_size)
+{
+ int x;
+
+ for (x = 0; x < src_size; x++)
+ sprintf(&dst[x * 2], "%.2x", (unsigned char)src[x]);
+}
+
+/**
+ * ecryptfs_from_hex
+ * @dst: Buffer to take the bytes from src hex; must be at least of
+ * size (src_size / 2)
+ * @src: Buffer to be converted from a hex string respresentation to raw value
+ * @dst_size: size of dst buffer, or number of hex characters pairs to convert
+ */
+void ecryptfs_from_hex(char *dst, char *src, int dst_size)
+{
+ int x;
+ char tmp[3] = { 0, };
+
+ for (x = 0; x < dst_size; x++) {
+ tmp[0] = src[x * 2];
+ tmp[1] = src[x * 2 + 1];
+ dst[x] = (unsigned char)simple_strtol(tmp, NULL, 16);
+ }
+}
+
+/**
+ * ecryptfs_calculate_md5 - calculates the md5 of @src
+ * @dst: Pointer to 16 bytes of allocated memory
+ * @crypt_stat: Pointer to crypt_stat struct for the current inode
+ * @src: Data to be md5'd
+ * @len: Length of @src
+ *
+ * Uses the allocated crypto context that crypt_stat references to
+ * generate the MD5 sum of the contents of src.
+ */
+static int ecryptfs_calculate_md5(char *dst,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ char *src, int len)
+{
+ int rc = 0;
+ struct scatterlist sg;
+
+ mutex_lock(&crypt_stat->cs_md5_tfm_mutex);
+ sg_init_one(&sg, (u8 *)src, len);
+ if (!crypt_stat->md5_tfm) {
+ crypt_stat->md5_tfm =
+ crypto_alloc_tfm("md5", CRYPTO_TFM_REQ_MAY_SLEEP);
+ if (!crypt_stat->md5_tfm) {
+ rc = -ENOMEM;
+ ecryptfs_printk(KERN_ERR, "Error attempting to "
+ "allocate crypto context\n");
+ goto out;
+ }
+ }
+ crypto_digest_init(crypt_stat->md5_tfm);
+ crypto_digest_update(crypt_stat->md5_tfm, &sg, 1);
+ crypto_digest_final(crypt_stat->md5_tfm, dst);
+ mutex_unlock(&crypt_stat->cs_md5_tfm_mutex);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_derive_iv
+ * @iv: destination for the derived iv vale
+ * @crypt_stat: Pointer to crypt_stat struct for the current inode
+ * @offset: Offset of the page whose's iv we are to derive
+ *
+ * Generate the initialization vector from the given root IV and page
+ * offset.
+ *
+ * Returns zero on success; non-zero on error.
+ */
+static int ecryptfs_derive_iv(char *iv, struct ecryptfs_crypt_stat *crypt_stat,
+ pgoff_t offset)
+{
+ int rc = 0;
+ char dst[MD5_DIGEST_SIZE];
+ char src[ECRYPTFS_MAX_IV_BYTES + 16];
+
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "root iv:\n");
+ ecryptfs_dump_hex(crypt_stat->root_iv, crypt_stat->iv_bytes);
+ }
+ /* TODO: It is probably secure to just cast the least
+ * significant bits of the root IV into an unsigned long and
+ * add the offset to that rather than go through all this
+ * hashing business. -Halcrow */
+ memcpy(src, crypt_stat->root_iv, crypt_stat->iv_bytes);
+ memset((src + crypt_stat->iv_bytes), 0, 16);
+ snprintf((src + crypt_stat->iv_bytes), 16, "%ld", offset);
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "source:\n");
+ ecryptfs_dump_hex(src, (crypt_stat->iv_bytes + 16));
+ }
+ rc = ecryptfs_calculate_md5(dst, crypt_stat, src,
+ (crypt_stat->iv_bytes + 16));
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error attempting to compute "
+ "MD5 while generating IV for a page\n");
+ goto out;
+ }
+ memcpy(iv, dst, crypt_stat->iv_bytes);
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "derived iv:\n");
+ ecryptfs_dump_hex(iv, crypt_stat->iv_bytes);
+ }
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_init_crypt_stat
+ * @crypt_stat: Pointer to the crypt_stat struct to initialize.
+ *
+ * Initialize the crypt_stat structure.
+ */
+void
+ecryptfs_init_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat)
+{
+ memset((void *)crypt_stat, 0, sizeof(struct ecryptfs_crypt_stat));
+ mutex_init(&crypt_stat->cs_mutex);
+ mutex_init(&crypt_stat->cs_tfm_mutex);
+ mutex_init(&crypt_stat->cs_md5_tfm_mutex);
+ ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_STRUCT_INITIALIZED);
+}
+
+/**
+ * ecryptfs_destruct_crypt_stat
+ * @crypt_stat: Pointer to the crypt_stat struct to initialize.
+ *
+ * Releases all memory associated with a crypt_stat struct.
+ */
+void ecryptfs_destruct_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat)
+{
+ if (crypt_stat->tfm)
+ crypto_free_tfm(crypt_stat->tfm);
+ if (crypt_stat->md5_tfm)
+ crypto_free_tfm(crypt_stat->md5_tfm);
+ memset(crypt_stat, 0, sizeof(struct ecryptfs_crypt_stat));
+}
+
+void ecryptfs_destruct_mount_crypt_stat(
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
+{
+ if (mount_crypt_stat->global_auth_tok_key)
+ key_put(mount_crypt_stat->global_auth_tok_key);
+ if (mount_crypt_stat->global_key_tfm)
+ crypto_free_tfm(mount_crypt_stat->global_key_tfm);
+ memset(mount_crypt_stat, 0, sizeof(struct ecryptfs_mount_crypt_stat));
+}
+
+/**
+ * virt_to_scatterlist
+ * @addr: Virtual address
+ * @size: Size of data; should be an even multiple of the block size
+ * @sg: Pointer to scatterlist array; set to NULL to obtain only
+ * the number of scatterlist structs required in array
+ * @sg_size: Max array size
+ *
+ * Fills in a scatterlist array with page references for a passed
+ * virtual address.
+ *
+ * Returns the number of scatterlist structs in array used
+ */
+int virt_to_scatterlist(const void *addr, int size, struct scatterlist *sg,
+ int sg_size)
+{
+ int i = 0;
+ struct page *pg;
+ int offset;
+ int remainder_of_page;
+
+ while (size > 0 && i < sg_size) {
+ pg = virt_to_page(addr);
+ offset = offset_in_page(addr);
+ if (sg) {
+ sg[i].page = pg;
+ sg[i].offset = offset;
+ }
+ remainder_of_page = PAGE_CACHE_SIZE - offset;
+ if (size >= remainder_of_page) {
+ if (sg)
+ sg[i].length = remainder_of_page;
+ addr += remainder_of_page;
+ size -= remainder_of_page;
+ } else {
+ if (sg)
+ sg[i].length = size;
+ addr += size;
+ size = 0;
+ }
+ i++;
+ }
+ if (size > 0)
+ return -ENOMEM;
+ return i;
+}
+
+/**
+ * encrypt_scatterlist
+ * @crypt_stat: Pointer to the crypt_stat struct to initialize.
+ * @dest_sg: Destination of encrypted data
+ * @src_sg: Data to be encrypted
+ * @size: Length of data to be encrypted
+ * @iv: iv to use during encryption
+ *
+ * Returns the number of bytes encrypted; negative value on error
+ */
+static int encrypt_scatterlist(struct ecryptfs_crypt_stat *crypt_stat,
+ struct scatterlist *dest_sg,
+ struct scatterlist *src_sg, int size,
+ unsigned char *iv)
+{
+ int rc = 0;
+
+ BUG_ON(!crypt_stat || !crypt_stat->tfm
+ || !ECRYPTFS_CHECK_FLAG(crypt_stat->flags,
+ ECRYPTFS_STRUCT_INITIALIZED));
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "Key size [%d]; key:\n",
+ crypt_stat->key_size);
+ ecryptfs_dump_hex(crypt_stat->key,
+ crypt_stat->key_size);
+ }
+ /* Consider doing this once, when the file is opened */
+ mutex_lock(&crypt_stat->cs_tfm_mutex);
+ rc = crypto_cipher_setkey(crypt_stat->tfm, crypt_stat->key,
+ crypt_stat->key_size);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error setting key; rc = [%d]\n",
+ rc);
+ mutex_unlock(&crypt_stat->cs_tfm_mutex);
+ rc = -EINVAL;
+ goto out;
+ }
+ ecryptfs_printk(KERN_DEBUG, "Encrypting [%d] bytes.\n", size);
+ crypto_cipher_encrypt_iv(crypt_stat->tfm, dest_sg, src_sg, size, iv);
+ mutex_unlock(&crypt_stat->cs_tfm_mutex);
+out:
+ return rc;
+}
+
+static void
+ecryptfs_extent_to_lwr_pg_idx_and_offset(unsigned long *lower_page_idx,
+ int *byte_offset,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ unsigned long extent_num)
+{
+ unsigned long lower_extent_num;
+ int extents_occupied_by_headers_at_front;
+ int bytes_occupied_by_headers_at_front;
+ int extent_offset;
+ int extents_per_page;
+
+ bytes_occupied_by_headers_at_front =
+ ( crypt_stat->header_extent_size
+ * crypt_stat->num_header_extents_at_front );
+ extents_occupied_by_headers_at_front =
+ ( bytes_occupied_by_headers_at_front
+ / crypt_stat->extent_size );
+ lower_extent_num = extents_occupied_by_headers_at_front + extent_num;
+ extents_per_page = PAGE_CACHE_SIZE / crypt_stat->extent_size;
+ (*lower_page_idx) = lower_extent_num / extents_per_page;
+ extent_offset = lower_extent_num % extents_per_page;
+ (*byte_offset) = extent_offset * crypt_stat->extent_size;
+ ecryptfs_printk(KERN_DEBUG, " * crypt_stat->header_extent_size = "
+ "[%d]\n", crypt_stat->header_extent_size);
+ ecryptfs_printk(KERN_DEBUG, " * crypt_stat->"
+ "num_header_extents_at_front = [%d]\n",
+ crypt_stat->num_header_extents_at_front);
+ ecryptfs_printk(KERN_DEBUG, " * extents_occupied_by_headers_at_"
+ "front = [%d]\n", extents_occupied_by_headers_at_front);
+ ecryptfs_printk(KERN_DEBUG, " * lower_extent_num = [0x%.16x]\n",
+ lower_extent_num);
+ ecryptfs_printk(KERN_DEBUG, " * extents_per_page = [%d]\n",
+ extents_per_page);
+ ecryptfs_printk(KERN_DEBUG, " * (*lower_page_idx) = [0x%.16x]\n",
+ (*lower_page_idx));
+ ecryptfs_printk(KERN_DEBUG, " * extent_offset = [%d]\n",
+ extent_offset);
+ ecryptfs_printk(KERN_DEBUG, " * (*byte_offset) = [%d]\n",
+ (*byte_offset));
+}
+
+static int ecryptfs_write_out_page(struct ecryptfs_page_crypt_context *ctx,
+ struct page *lower_page,
+ struct inode *lower_inode,
+ int byte_offset_in_page, int bytes_to_write)
+{
+ int rc = 0;
+
+ if (ctx->mode == ECRYPTFS_PREPARE_COMMIT_MODE) {
+ rc = ecryptfs_commit_lower_page(lower_page, lower_inode,
+ ctx->param.lower_file,
+ byte_offset_in_page,
+ bytes_to_write);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error calling lower "
+ "commit; rc = [%d]\n", rc);
+ goto out;
+ }
+ } else {
+ rc = ecryptfs_writepage_and_release_lower_page(lower_page,
+ lower_inode,
+ ctx->param.wbc);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error calling lower "
+ "writepage(); rc = [%d]\n", rc);
+ goto out;
+ }
+ }
+out:
+ return rc;
+}
+
+static int ecryptfs_read_in_page(struct ecryptfs_page_crypt_context *ctx,
+ struct page **lower_page,
+ struct inode *lower_inode,
+ unsigned long lower_page_idx,
+ int byte_offset_in_page)
+{
+ int rc = 0;
+
+ if (ctx->mode == ECRYPTFS_PREPARE_COMMIT_MODE) {
+ /* TODO: Limit this to only the data extents that are
+ * needed */
+ rc = ecryptfs_get_lower_page(lower_page, lower_inode,
+ ctx->param.lower_file,
+ lower_page_idx,
+ byte_offset_in_page,
+ (PAGE_CACHE_SIZE
+ - byte_offset_in_page));
+ if (rc) {
+ ecryptfs_printk(
+ KERN_ERR, "Error attempting to grab, map, "
+ "and prepare_write lower page with index "
+ "[0x%.16x]; rc = [%d]\n", lower_page_idx, rc);
+ goto out;
+ }
+ } else {
+ rc = ecryptfs_grab_and_map_lower_page(lower_page, NULL,
+ lower_inode,
+ lower_page_idx);
+ if (rc) {
+ ecryptfs_printk(
+ KERN_ERR, "Error attempting to grab and map "
+ "lower page with index [0x%.16x]; rc = [%d]\n",
+ lower_page_idx, rc);
+ goto out;
+ }
+ }
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_encrypt_page
+ * @ctx: The context of the page
+ *
+ * Encrypt an eCryptfs page. This is done on a per-extent basis. Note
+ * that eCryptfs pages may straddle the lower pages -- for instance,
+ * if the file was created on a machine with an 8K page size
+ * (resulting in an 8K header), and then the file is copied onto a
+ * host with a 32K page size, then when reading page 0 of the eCryptfs
+ * file, 24K of page 0 of the lower file will be read and decrypted,
+ * and then 8K of page 1 of the lower file will be read and decrypted.
+ *
+ * The actual operations performed on each page depends on the
+ * contents of the ecryptfs_page_crypt_context struct.
+ *
+ * Returns zero on success; negative on error
+ */
+int ecryptfs_encrypt_page(struct ecryptfs_page_crypt_context *ctx)
+{
+ char extent_iv[ECRYPTFS_MAX_IV_BYTES];
+ unsigned long base_extent;
+ unsigned long extent_offset = 0;
+ unsigned long lower_page_idx = 0;
+ unsigned long prior_lower_page_idx = 0;
+ struct page *lower_page;
+ struct inode *lower_inode;
+ struct ecryptfs_inode_info *inode_info;
+ struct ecryptfs_crypt_stat *crypt_stat;
+ int rc = 0;
+ int lower_byte_offset = 0;
+ int orig_byte_offset = 0;
+ int num_extents_per_page;
+#define ECRYPTFS_PAGE_STATE_UNREAD 0
+#define ECRYPTFS_PAGE_STATE_READ 1
+#define ECRYPTFS_PAGE_STATE_MODIFIED 2
+#define ECRYPTFS_PAGE_STATE_WRITTEN 3
+ int page_state;
+
+ lower_inode = ecryptfs_inode_to_lower(ctx->page->mapping->host);
+ inode_info = ecryptfs_inode_to_private(ctx->page->mapping->host);
+ crypt_stat = &inode_info->crypt_stat;
+ if (!ECRYPTFS_CHECK_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED)) {
+ rc = ecryptfs_copy_page_to_lower(ctx->page, lower_inode,
+ ctx->param.lower_file);
+ if (rc)
+ ecryptfs_printk(KERN_ERR, "Error attempting to copy "
+ "page at index [0x%.16x]\n",
+ ctx->page->index);
+ goto out;
+ }
+ num_extents_per_page = PAGE_CACHE_SIZE / crypt_stat->extent_size;
+ base_extent = (ctx->page->index * num_extents_per_page);
+ page_state = ECRYPTFS_PAGE_STATE_UNREAD;
+ while (extent_offset < num_extents_per_page) {
+ ecryptfs_extent_to_lwr_pg_idx_and_offset(
+ &lower_page_idx, &lower_byte_offset, crypt_stat,
+ (base_extent + extent_offset));
+ if (prior_lower_page_idx != lower_page_idx
+ && page_state == ECRYPTFS_PAGE_STATE_MODIFIED) {
+ rc = ecryptfs_write_out_page(ctx, lower_page,
+ lower_inode,
+ orig_byte_offset,
+ (PAGE_CACHE_SIZE
+ - orig_byte_offset));
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error attempting "
+ "to write out page; rc = [%d]"
+ "\n", rc);
+ goto out;
+ }
+ page_state = ECRYPTFS_PAGE_STATE_WRITTEN;
+ }
+ if (page_state == ECRYPTFS_PAGE_STATE_UNREAD
+ || page_state == ECRYPTFS_PAGE_STATE_WRITTEN) {
+ rc = ecryptfs_read_in_page(ctx, &lower_page,
+ lower_inode, lower_page_idx,
+ lower_byte_offset);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error attempting "
+ "to read in lower page with "
+ "index [0x%.16x]; rc = [%d]\n",
+ lower_page_idx, rc);
+ goto out;
+ }
+ orig_byte_offset = lower_byte_offset;
+ prior_lower_page_idx = lower_page_idx;
+ page_state = ECRYPTFS_PAGE_STATE_READ;
+ }
+ BUG_ON(!(page_state == ECRYPTFS_PAGE_STATE_MODIFIED
+ || page_state == ECRYPTFS_PAGE_STATE_READ));
+ rc = ecryptfs_derive_iv(extent_iv, crypt_stat,
+ (base_extent + extent_offset));
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error attempting to "
+ "derive IV for extent [0x%.16x]; "
+ "rc = [%d]\n",
+ (base_extent + extent_offset), rc);
+ goto out;
+ }
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "Encrypting extent "
+ "with iv:\n");
+ ecryptfs_dump_hex(extent_iv, crypt_stat->iv_bytes);
+ ecryptfs_printk(KERN_DEBUG, "First 8 bytes before "
+ "encryption:\n");
+ ecryptfs_dump_hex((char *)
+ (page_address(ctx->page)
+ + (extent_offset
+ * crypt_stat->extent_size)), 8);
+ }
+ rc = ecryptfs_encrypt_page_offset(
+ crypt_stat, lower_page, lower_byte_offset, ctx->page,
+ (extent_offset * crypt_stat->extent_size),
+ crypt_stat->extent_size, extent_iv);
+ ecryptfs_printk(KERN_DEBUG, "Encrypt extent [0x%.16x]; "
+ "rc = [%d]\n",
+ (base_extent + extent_offset), rc);
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "First 8 bytes after "
+ "encryption:\n");
+ ecryptfs_dump_hex((char *)(page_address(lower_page)
+ + lower_byte_offset), 8);
+ }
+ page_state = ECRYPTFS_PAGE_STATE_MODIFIED;
+ extent_offset++;
+ }
+ BUG_ON(orig_byte_offset != 0);
+ rc = ecryptfs_write_out_page(ctx, lower_page, lower_inode, 0,
+ (lower_byte_offset
+ + crypt_stat->extent_size));
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error attempting to write out "
+ "page; rc = [%d]\n", rc);
+ goto out;
+ }
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_decrypt_page
+ * @file: The ecryptfs file
+ * @page: The page in ecryptfs to decrypt
+ *
+ * Decrypt an eCryptfs page. This is done on a per-extent basis. Note
+ * that eCryptfs pages may straddle the lower pages -- for instance,
+ * if the file was created on a machine with an 8K page size
+ * (resulting in an 8K header), and then the file is copied onto a
+ * host with a 32K page size, then when reading page 0 of the eCryptfs
+ * file, 24K of page 0 of the lower file will be read and decrypted,
+ * and then 8K of page 1 of the lower file will be read and decrypted.
+ *
+ * Returns zero on success; negative on error
+ */
+int ecryptfs_decrypt_page(struct file *file, struct page *page)
+{
+ char extent_iv[ECRYPTFS_MAX_IV_BYTES];
+ unsigned long base_extent;
+ unsigned long extent_offset = 0;
+ unsigned long lower_page_idx = 0;
+ unsigned long prior_lower_page_idx = 0;
+ struct page *lower_page;
+ char *lower_page_virt = NULL;
+ struct inode *lower_inode;
+ struct ecryptfs_crypt_stat *crypt_stat;
+ int rc = 0;
+ int byte_offset;
+ int num_extents_per_page;
+ int page_state;
+
+ crypt_stat = &(ecryptfs_inode_to_private(
+ page->mapping->host)->crypt_stat);
+ lower_inode = ecryptfs_inode_to_lower(page->mapping->host);
+ if (!ECRYPTFS_CHECK_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED)) {
+ rc = ecryptfs_do_readpage(file, page, page->index);
+ if (rc)
+ ecryptfs_printk(KERN_ERR, "Error attempting to copy "
+ "page at index [0x%.16x]\n",
+ page->index);
+ goto out;
+ }
+ num_extents_per_page = PAGE_CACHE_SIZE / crypt_stat->extent_size;
+ base_extent = (page->index * num_extents_per_page);
+ lower_page_virt = kmem_cache_alloc(ecryptfs_lower_page_cache,
+ SLAB_KERNEL);
+ if (!lower_page_virt) {
+ rc = -ENOMEM;
+ ecryptfs_printk(KERN_ERR, "Error getting page for encrypted "
+ "lower page(s)\n");
+ goto out;
+ }
+ lower_page = virt_to_page(lower_page_virt);
+ page_state = ECRYPTFS_PAGE_STATE_UNREAD;
+ while (extent_offset < num_extents_per_page) {
+ ecryptfs_extent_to_lwr_pg_idx_and_offset(
+ &lower_page_idx, &byte_offset, crypt_stat,
+ (base_extent + extent_offset));
+ if (prior_lower_page_idx != lower_page_idx
+ || page_state == ECRYPTFS_PAGE_STATE_UNREAD) {
+ rc = ecryptfs_do_readpage(file, lower_page,
+ lower_page_idx);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error reading "
+ "lower encrypted page; rc = "
+ "[%d]\n", rc);
+ goto out;
+ }
+ prior_lower_page_idx = lower_page_idx;
+ page_state = ECRYPTFS_PAGE_STATE_READ;
+ }
+ rc = ecryptfs_derive_iv(extent_iv, crypt_stat,
+ (base_extent + extent_offset));
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error attempting to "
+ "derive IV for extent [0x%.16x]; rc = "
+ "[%d]\n",
+ (base_extent + extent_offset), rc);
+ goto out;
+ }
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "Decrypting extent "
+ "with iv:\n");
+ ecryptfs_dump_hex(extent_iv, crypt_stat->iv_bytes);
+ ecryptfs_printk(KERN_DEBUG, "First 8 bytes before "
+ "decryption:\n");
+ ecryptfs_dump_hex((lower_page_virt + byte_offset), 8);
+ }
+ rc = ecryptfs_decrypt_page_offset(crypt_stat, page,
+ (extent_offset
+ * crypt_stat->extent_size),
+ lower_page, byte_offset,
+ crypt_stat->extent_size,
+ extent_iv);
+ if (rc != crypt_stat->extent_size) {
+ ecryptfs_printk(KERN_ERR, "Error attempting to "
+ "decrypt extent [0x%.16x]\n",
+ (base_extent + extent_offset));
+ goto out;
+ }
+ rc = 0;
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "First 8 bytes after "
+ "decryption:\n");
+ ecryptfs_dump_hex((char *)(page_address(page)
+ + byte_offset), 8);
+ }
+ extent_offset++;
+ }
+out:
+ if (lower_page_virt)
+ kmem_cache_free(ecryptfs_lower_page_cache, lower_page_virt);
+ return rc;
+}
+
+/**
+ * decrypt_scatterlist
+ *
+ * Returns the number of bytes decrypted; negative value on error
+ */
+static int decrypt_scatterlist(struct ecryptfs_crypt_stat *crypt_stat,
+ struct scatterlist *dest_sg,
+ struct scatterlist *src_sg, int size,
+ unsigned char *iv)
+{
+ int rc = 0;
+
+ /* Consider doing this once, when the file is opened */
+ mutex_lock(&crypt_stat->cs_tfm_mutex);
+ rc = crypto_cipher_setkey(crypt_stat->tfm, crypt_stat->key,
+ crypt_stat->key_size);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error setting key; rc = [%d]\n",
+ rc);
+ mutex_unlock(&crypt_stat->cs_tfm_mutex);
+ rc = -EINVAL;
+ goto out;
+ }
+ ecryptfs_printk(KERN_DEBUG, "Decrypting [%d] bytes.\n", size);
+ rc = crypto_cipher_decrypt_iv(crypt_stat->tfm, dest_sg, src_sg, size,
+ iv);
+ mutex_unlock(&crypt_stat->cs_tfm_mutex);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error decrypting; rc = [%d]\n",
+ rc);
+ goto out;
+ }
+ rc = size;
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_encrypt_page_offset
+ *
+ * Returns the number of bytes encrypted
+ */
+static int
+ecryptfs_encrypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat,
+ struct page *dst_page, int dst_offset,
+ struct page *src_page, int src_offset, int size,
+ unsigned char *iv)
+{
+ struct scatterlist src_sg, dst_sg;
+
+ src_sg.page = src_page;
+ src_sg.offset = src_offset;
+ src_sg.length = size;
+ dst_sg.page = dst_page;
+ dst_sg.offset = dst_offset;
+ dst_sg.length = size;
+ return encrypt_scatterlist(crypt_stat, &dst_sg, &src_sg, size, iv);
+}
+
+/**
+ * ecryptfs_decrypt_page_offset
+ *
+ * Returns the number of bytes decrypted
+ */
+static int
+ecryptfs_decrypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat,
+ struct page *dst_page, int dst_offset,
+ struct page *src_page, int src_offset, int size,
+ unsigned char *iv)
+{
+ struct scatterlist src_sg, dst_sg;
+
+ src_sg.page = src_page;
+ src_sg.offset = src_offset;
+ src_sg.length = size;
+ dst_sg.page = dst_page;
+ dst_sg.offset = dst_offset;
+ dst_sg.length = size;
+ return decrypt_scatterlist(crypt_stat, &dst_sg, &src_sg, size, iv);
+}
+
+#define ECRYPTFS_MAX_SCATTERLIST_LEN 4
+
+/**
+ * ecryptfs_init_crypt_ctx
+ * @crypt_stat: Uninitilized crypt stats structure
+ *
+ * Initialize the crypto context.
+ *
+ * TODO: Performance: Keep a cache of initialized cipher contexts;
+ * only init if needed
+ */
+int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat)
+{
+ int rc = -EINVAL;
+
+ if (!crypt_stat->cipher) {
+ ecryptfs_printk(KERN_ERR, "No cipher specified\n");
+ goto out;
+ }
+ ecryptfs_printk(KERN_DEBUG,
+ "Initializing cipher [%s]; strlen = [%d]; "
+ "key_size_bits = [%d]\n",
+ crypt_stat->cipher, (int)strlen(crypt_stat->cipher),
+ crypt_stat->key_size << 3);
+ if (crypt_stat->tfm) {
+ rc = 0;
+ goto out;
+ }
+ mutex_lock(&crypt_stat->cs_tfm_mutex);
+ crypt_stat->tfm = crypto_alloc_tfm(crypt_stat->cipher,
+ ECRYPTFS_DEFAULT_CHAINING_MODE
+ | CRYPTO_TFM_REQ_WEAK_KEY);
+ mutex_unlock(&crypt_stat->cs_tfm_mutex);
+ if (!crypt_stat->tfm) {
+ ecryptfs_printk(KERN_ERR, "cryptfs: init_crypt_ctx(): "
+ "Error initializing cipher [%s]\n",
+ crypt_stat->cipher);
+ goto out;
+ }
+ rc = 0;
+out:
+ return rc;
+}
+
+static void set_extent_mask_and_shift(struct ecryptfs_crypt_stat *crypt_stat)
+{
+ int extent_size_tmp;
+
+ crypt_stat->extent_mask = 0xFFFFFFFF;
+ crypt_stat->extent_shift = 0;
+ if (crypt_stat->extent_size == 0)
+ return;
+ extent_size_tmp = crypt_stat->extent_size;
+ while ((extent_size_tmp & 0x01) == 0) {
+ extent_size_tmp >>= 1;
+ crypt_stat->extent_mask <<= 1;
+ crypt_stat->extent_shift++;
+ }
+}
+
+void ecryptfs_set_default_sizes(struct ecryptfs_crypt_stat *crypt_stat)
+{
+ /* Default values; may be overwritten as we are parsing the
+ * packets. */
+ crypt_stat->extent_size = ECRYPTFS_DEFAULT_EXTENT_SIZE;
+ set_extent_mask_and_shift(crypt_stat);
+ crypt_stat->iv_bytes = ECRYPTFS_DEFAULT_IV_BYTES;
+ if (PAGE_CACHE_SIZE <= ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE) {
+ crypt_stat->header_extent_size =
+ ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE;
+ } else
+ crypt_stat->header_extent_size = PAGE_CACHE_SIZE;
+ crypt_stat->num_header_extents_at_front = 1;
+}
+
+/**
+ * ecryptfs_compute_root_iv
+ * @crypt_stats
+ *
+ * On error, sets the root IV to all 0's.
+ */
+int ecryptfs_compute_root_iv(struct ecryptfs_crypt_stat *crypt_stat)
+{
+ int rc = 0;
+ char dst[MD5_DIGEST_SIZE];
+
+ BUG_ON(crypt_stat->iv_bytes > MD5_DIGEST_SIZE);
+ BUG_ON(crypt_stat->iv_bytes <= 0);
+ if (!ECRYPTFS_CHECK_FLAG(crypt_stat->flags, ECRYPTFS_KEY_VALID)) {
+ rc = -EINVAL;
+ ecryptfs_printk(KERN_WARNING, "Session key not valid; "
+ "cannot generate root IV\n");
+ goto out;
+ }
+ rc = ecryptfs_calculate_md5(dst, crypt_stat, crypt_stat->key,
+ crypt_stat->key_size);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error attempting to compute "
+ "MD5 while generating root IV\n");
+ goto out;
+ }
+ memcpy(crypt_stat->root_iv, dst, crypt_stat->iv_bytes);
+out:
+ if (rc) {
+ memset(crypt_stat->root_iv, 0, crypt_stat->iv_bytes);
+ ECRYPTFS_SET_FLAG(crypt_stat->flags,
+ ECRYPTFS_SECURITY_WARNING);
+ }
+ return rc;
+}
+
+static void ecryptfs_generate_new_key(struct ecryptfs_crypt_stat *crypt_stat)
+{
+ get_random_bytes(crypt_stat->key, crypt_stat->key_size);
+ ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_KEY_VALID);
+ ecryptfs_compute_root_iv(crypt_stat);
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "Generated new session key:\n");
+ ecryptfs_dump_hex(crypt_stat->key,
+ crypt_stat->key_size);
+ }
+}
+
+/**
+ * ecryptfs_set_default_crypt_stat_vals
+ * @crypt_stat
+ *
+ * Default values in the event that policy does not override them.
+ */
+static void ecryptfs_set_default_crypt_stat_vals(
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
+{
+ ecryptfs_set_default_sizes(crypt_stat);
+ strcpy(crypt_stat->cipher, ECRYPTFS_DEFAULT_CIPHER);
+ crypt_stat->key_size = ECRYPTFS_DEFAULT_KEY_BYTES;
+ ECRYPTFS_CLEAR_FLAG(crypt_stat->flags, ECRYPTFS_KEY_VALID);
+ crypt_stat->file_version = ECRYPTFS_FILE_VERSION;
+ crypt_stat->mount_crypt_stat = mount_crypt_stat;
+}
+
+/**
+ * ecryptfs_new_file_context
+ * @ecryptfs_dentry
+ *
+ * If the crypto context for the file has not yet been established,
+ * this is where we do that. Establishing a new crypto context
+ * involves the following decisions:
+ * - What cipher to use?
+ * - What set of authentication tokens to use?
+ * Here we just worry about getting enough information into the
+ * authentication tokens so that we know that they are available.
+ * We associate the available authentication tokens with the new file
+ * via the set of signatures in the crypt_stat struct. Later, when
+ * the headers are actually written out, we may again defer to
+ * userspace to perform the encryption of the session key; for the
+ * foreseeable future, this will be the case with public key packets.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+/* Associate an authentication token(s) with the file */
+int ecryptfs_new_file_context(struct dentry *ecryptfs_dentry)
+{
+ int rc = 0;
+ struct ecryptfs_crypt_stat *crypt_stat =
+ &ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
+ &ecryptfs_superblock_to_private(
+ ecryptfs_dentry->d_sb)->mount_crypt_stat;
+ int cipher_name_len;
+
+ ecryptfs_set_default_crypt_stat_vals(crypt_stat, mount_crypt_stat);
+ /* See if there are mount crypt options */
+ if (mount_crypt_stat->global_auth_tok) {
+ ecryptfs_printk(KERN_DEBUG, "Initializing context for new "
+ "file using mount_crypt_stat\n");
+ ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED);
+ ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_KEY_VALID);
+ memcpy(crypt_stat->keysigs[crypt_stat->num_keysigs++],
+ mount_crypt_stat->global_auth_tok_sig,
+ ECRYPTFS_SIG_SIZE_HEX);
+ cipher_name_len =
+ strlen(mount_crypt_stat->global_default_cipher_name);
+ memcpy(crypt_stat->cipher,
+ mount_crypt_stat->global_default_cipher_name,
+ cipher_name_len);
+ crypt_stat->cipher[cipher_name_len] = '\0';
+ crypt_stat->key_size =
+ mount_crypt_stat->global_default_cipher_key_size;
+ ecryptfs_generate_new_key(crypt_stat);
+ } else
+ /* We should not encounter this scenario since we
+ * should detect lack of global_auth_tok at mount time
+ * TODO: Applies to 0.1 release only; remove in future
+ * release */
+ BUG();
+ rc = ecryptfs_init_crypt_ctx(crypt_stat);
+ if (rc)
+ ecryptfs_printk(KERN_ERR, "Error initializing cryptographic "
+ "context for cipher [%s]: rc = [%d]\n",
+ crypt_stat->cipher, rc);
+ return rc;
+}
+
+/**
+ * contains_ecryptfs_marker - check for the ecryptfs marker
+ * @data: The data block in which to check
+ *
+ * Returns one if marker found; zero if not found
+ */
+int contains_ecryptfs_marker(char *data)
+{
+ u32 m_1, m_2;
+
+ memcpy(&m_1, data, 4);
+ m_1 = be32_to_cpu(m_1);
+ memcpy(&m_2, (data + 4), 4);
+ m_2 = be32_to_cpu(m_2);
+ if ((m_1 ^ MAGIC_ECRYPTFS_MARKER) == m_2)
+ return 1;
+ ecryptfs_printk(KERN_DEBUG, "m_1 = [0x%.8x]; m_2 = [0x%.8x]; "
+ "MAGIC_ECRYPTFS_MARKER = [0x%.8x]\n", m_1, m_2,
+ MAGIC_ECRYPTFS_MARKER);
+ ecryptfs_printk(KERN_DEBUG, "(m_1 ^ MAGIC_ECRYPTFS_MARKER) = "
+ "[0x%.8x]\n", (m_1 ^ MAGIC_ECRYPTFS_MARKER));
+ return 0;
+}
+
+struct ecryptfs_flag_map_elem {
+ u32 file_flag;
+ u32 local_flag;
+};
+
+/* Add support for additional flags by adding elements here. */
+static struct ecryptfs_flag_map_elem ecryptfs_flag_map[] = {
+ {0x00000001, ECRYPTFS_ENABLE_HMAC},
+ {0x00000002, ECRYPTFS_ENCRYPTED}
+};
+
+/**
+ * ecryptfs_process_flags
+ * @crypt_stat
+ * @page_virt: Source data to be parsed
+ * @bytes_read: Updated with the number of bytes read
+ *
+ * Returns zero on success; non-zero if the flag set is invalid
+ */
+static int ecryptfs_process_flags(struct ecryptfs_crypt_stat *crypt_stat,
+ char *page_virt, int *bytes_read)
+{
+ int rc = 0;
+ int i;
+ u32 flags;
+
+ memcpy(&flags, page_virt, 4);
+ flags = be32_to_cpu(flags);
+ for (i = 0; i < ((sizeof(ecryptfs_flag_map)
+ / sizeof(struct ecryptfs_flag_map_elem))); i++)
+ if (flags & ecryptfs_flag_map[i].file_flag) {
+ ECRYPTFS_SET_FLAG(crypt_stat->flags,
+ ecryptfs_flag_map[i].local_flag);
+ } else
+ ECRYPTFS_CLEAR_FLAG(crypt_stat->flags,
+ ecryptfs_flag_map[i].local_flag);
+ /* Version is in top 8 bits of the 32-bit flag vector */
+ crypt_stat->file_version = ((flags >> 24) & 0xFF);
+ (*bytes_read) = 4;
+ return rc;
+}
+
+/**
+ * write_ecryptfs_marker
+ * @page_virt: The pointer to in a page to begin writing the marker
+ * @written: Number of bytes written
+ *
+ * Marker = 0x3c81b7f5
+ */
+static void write_ecryptfs_marker(char *page_virt, size_t *written)
+{
+ u32 m_1, m_2;
+
+ get_random_bytes(&m_1, (MAGIC_ECRYPTFS_MARKER_SIZE_BYTES / 2));
+ m_2 = (m_1 ^ MAGIC_ECRYPTFS_MARKER);
+ m_1 = cpu_to_be32(m_1);
+ memcpy(page_virt, &m_1, (MAGIC_ECRYPTFS_MARKER_SIZE_BYTES / 2));
+ m_2 = cpu_to_be32(m_2);
+ memcpy(page_virt + (MAGIC_ECRYPTFS_MARKER_SIZE_BYTES / 2), &m_2,
+ (MAGIC_ECRYPTFS_MARKER_SIZE_BYTES / 2));
+ (*written) = MAGIC_ECRYPTFS_MARKER_SIZE_BYTES;
+}
+
+static void
+write_ecryptfs_flags(char *page_virt, struct ecryptfs_crypt_stat *crypt_stat,
+ size_t *written)
+{
+ u32 flags = 0;
+ int i;
+
+ for (i = 0; i < ((sizeof(ecryptfs_flag_map)
+ / sizeof(struct ecryptfs_flag_map_elem))); i++)
+ if (ECRYPTFS_CHECK_FLAG(crypt_stat->flags,
+ ecryptfs_flag_map[i].local_flag))
+ flags |= ecryptfs_flag_map[i].file_flag;
+ /* Version is in top 8 bits of the 32-bit flag vector */
+ flags |= ((((u8)crypt_stat->file_version) << 24) & 0xFF000000);
+ flags = cpu_to_be32(flags);
+ memcpy(page_virt, &flags, 4);
+ (*written) = 4;
+}
+
+struct ecryptfs_cipher_code_str_map_elem {
+ char cipher_str[16];
+ u16 cipher_code;
+};
+
+/* Add support for additional ciphers by adding elements here. The
+ * cipher_code is whatever OpenPGP applicatoins use to identify the
+ * ciphers. List in order of probability. */
+static struct ecryptfs_cipher_code_str_map_elem
+ecryptfs_cipher_code_str_map[] = {
+ {"aes",RFC2440_CIPHER_AES_128 },
+ {"blowfish", RFC2440_CIPHER_BLOWFISH},
+ {"des3_ede", RFC2440_CIPHER_DES3_EDE},
+ {"cast5", RFC2440_CIPHER_CAST_5},
+ {"twofish", RFC2440_CIPHER_TWOFISH},
+ {"cast6", RFC2440_CIPHER_CAST_6},
+ {"aes", RFC2440_CIPHER_AES_192},
+ {"aes", RFC2440_CIPHER_AES_256}
+};
+
+/**
+ * ecryptfs_code_for_cipher_string
+ * @str: The string representing the cipher name
+ *
+ * Returns zero on no match, or the cipher code on match
+ */
+u16 ecryptfs_code_for_cipher_string(struct ecryptfs_crypt_stat *crypt_stat)
+{
+ int i;
+ u16 code = 0;
+ struct ecryptfs_cipher_code_str_map_elem *map =
+ ecryptfs_cipher_code_str_map;
+
+ if (strcmp(crypt_stat->cipher, "aes") == 0) {
+ switch (crypt_stat->key_size) {
+ case 16:
+ code = RFC2440_CIPHER_AES_128;
+ break;
+ case 24:
+ code = RFC2440_CIPHER_AES_192;
+ break;
+ case 32:
+ code = RFC2440_CIPHER_AES_256;
+ }
+ } else {
+ for (i = 0; i < ARRAY_SIZE(ecryptfs_cipher_code_str_map); i++)
+ if (strcmp(crypt_stat->cipher, map[i].cipher_str) == 0){
+ code = map[i].cipher_code;
+ break;
+ }
+ }
+ return code;
+}
+
+/**
+ * ecryptfs_cipher_code_to_string
+ * @str: Destination to write out the cipher name
+ * @cipher_code: The code to convert to cipher name string
+ *
+ * Returns zero on success
+ */
+int ecryptfs_cipher_code_to_string(char *str, u16 cipher_code)
+{
+ int rc = 0;
+ int i;
+
+ str[0] = '\0';
+ for (i = 0; i < ARRAY_SIZE(ecryptfs_cipher_code_str_map); i++)
+ if (cipher_code == ecryptfs_cipher_code_str_map[i].cipher_code)
+ strcpy(str, ecryptfs_cipher_code_str_map[i].cipher_str);
+ if (str[0] == '\0') {
+ ecryptfs_printk(KERN_WARNING, "Cipher code not recognized: "
+ "[%d]\n", cipher_code);
+ rc = -EINVAL;
+ }
+ return rc;
+}
+
+/**
+ * ecryptfs_read_header_region
+ * @data
+ * @dentry
+ * @nd
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+int ecryptfs_read_header_region(char *data, struct dentry *dentry,
+ struct vfsmount *mnt)
+{
+ struct file *file;
+ mm_segment_t oldfs;
+ int rc;
+
+ mnt = mntget(mnt);
+ file = dentry_open(dentry, mnt, O_RDONLY);
+ if (IS_ERR(file)) {
+ ecryptfs_printk(KERN_DEBUG, "Error opening file to "
+ "read header region\n");
+ mntput(mnt);
+ rc = PTR_ERR(file);
+ goto out;
+ }
+ file->f_pos = 0;
+ oldfs = get_fs();
+ set_fs(get_ds());
+ /* For releases 0.1 and 0.2, all of the header information
+ * fits in the first data extent-sized region. */
+ rc = file->f_op->read(file, (char __user *)data,
+ ECRYPTFS_DEFAULT_EXTENT_SIZE, &file->f_pos);
+ set_fs(oldfs);
+ fput(file);
+ rc = 0;
+out:
+ return rc;
+}
+
+static void
+write_header_metadata(char *virt, struct ecryptfs_crypt_stat *crypt_stat,
+ size_t *written)
+{
+ u32 header_extent_size;
+ u16 num_header_extents_at_front;
+
+ header_extent_size = (u32)crypt_stat->header_extent_size;
+ num_header_extents_at_front =
+ (u16)crypt_stat->num_header_extents_at_front;
+ header_extent_size = cpu_to_be32(header_extent_size);
+ memcpy(virt, &header_extent_size, 4);
+ virt += 4;
+ num_header_extents_at_front = cpu_to_be16(num_header_extents_at_front);
+ memcpy(virt, &num_header_extents_at_front, 2);
+ (*written) = 6;
+}
+
+struct kmem_cache *ecryptfs_header_cache_0;
+struct kmem_cache *ecryptfs_header_cache_1;
+struct kmem_cache *ecryptfs_header_cache_2;
+
+/**
+ * ecryptfs_write_headers_virt
+ * @page_virt
+ * @crypt_stat
+ * @ecryptfs_dentry
+ *
+ * Format version: 1
+ *
+ * Header Extent:
+ * Octets 0-7: Unencrypted file size (big-endian)
+ * Octets 8-15: eCryptfs special marker
+ * Octets 16-19: Flags
+ * Octet 16: File format version number (between 0 and 255)
+ * Octets 17-18: Reserved
+ * Octet 19: Bit 1 (lsb): Reserved
+ * Bit 2: Encrypted?
+ * Bits 3-8: Reserved
+ * Octets 20-23: Header extent size (big-endian)
+ * Octets 24-25: Number of header extents at front of file
+ * (big-endian)
+ * Octet 26: Begin RFC 2440 authentication token packet set
+ * Data Extent 0:
+ * Lower data (CBC encrypted)
+ * Data Extent 1:
+ * Lower data (CBC encrypted)
+ * ...
+ *
+ * Returns zero on success
+ */
+int ecryptfs_write_headers_virt(char *page_virt,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct dentry *ecryptfs_dentry)
+{
+ int rc;
+ size_t written;
+ size_t offset;
+
+ offset = ECRYPTFS_FILE_SIZE_BYTES;
+ write_ecryptfs_marker((page_virt + offset), &written);
+ offset += written;
+ write_ecryptfs_flags((page_virt + offset), crypt_stat, &written);
+ offset += written;
+ write_header_metadata((page_virt + offset), crypt_stat, &written);
+ offset += written;
+ rc = ecryptfs_generate_key_packet_set((page_virt + offset), crypt_stat,
+ ecryptfs_dentry, &written,
+ PAGE_CACHE_SIZE - offset);
+ if (rc)
+ ecryptfs_printk(KERN_WARNING, "Error generating key packet "
+ "set; rc = [%d]\n", rc);
+ return rc;
+}
+
+/**
+ * ecryptfs_write_headers
+ * @lower_file: The lower file struct, which was returned from dentry_open
+ *
+ * Write the file headers out. This will likely involve a userspace
+ * callout, in which the session key is encrypted with one or more
+ * public keys and/or the passphrase necessary to do the encryption is
+ * retrieved via a prompt. Exactly what happens at this point should
+ * be policy-dependent.
+ *
+ * Returns zero on success; non-zero on error
+ */
+int ecryptfs_write_headers(struct dentry *ecryptfs_dentry,
+ struct file *lower_file)
+{
+ mm_segment_t oldfs;
+ struct ecryptfs_crypt_stat *crypt_stat;
+ char *page_virt;
+ int current_header_page;
+ int header_pages;
+ int rc = 0;
+
+ crypt_stat = &ecryptfs_inode_to_private(
+ ecryptfs_dentry->d_inode)->crypt_stat;
+ if (likely(ECRYPTFS_CHECK_FLAG(crypt_stat->flags,
+ ECRYPTFS_ENCRYPTED))) {
+ if (!ECRYPTFS_CHECK_FLAG(crypt_stat->flags,
+ ECRYPTFS_KEY_VALID)) {
+ ecryptfs_printk(KERN_DEBUG, "Key is "
+ "invalid; bailing out\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ } else {
+ rc = -EINVAL;
+ ecryptfs_printk(KERN_WARNING,
+ "Called with crypt_stat->encrypted == 0\n");
+ goto out;
+ }
+ /* Released in this function */
+ page_virt = kmem_cache_alloc(ecryptfs_header_cache_0, SLAB_USER);
+ if (!page_virt) {
+ ecryptfs_printk(KERN_ERR, "Out of memory\n");
+ rc = -ENOMEM;
+ goto out;
+ }
+ memset(page_virt, 0, PAGE_CACHE_SIZE);
+ rc = ecryptfs_write_headers_virt(page_virt, crypt_stat,
+ ecryptfs_dentry);
+ if (unlikely(rc)) {
+ ecryptfs_printk(KERN_ERR, "Error whilst writing headers\n");
+ memset(page_virt, 0, PAGE_CACHE_SIZE);
+ goto out_free;
+ }
+ ecryptfs_printk(KERN_DEBUG,
+ "Writing key packet set to underlying file\n");
+ lower_file->f_pos = 0;
+ oldfs = get_fs();
+ set_fs(get_ds());
+ ecryptfs_printk(KERN_DEBUG, "Calling lower_file->f_op->"
+ "write() w/ header page; lower_file->f_pos = "
+ "[0x%.16x]\n", lower_file->f_pos);
+ lower_file->f_op->write(lower_file, (char __user *)page_virt,
+ PAGE_CACHE_SIZE, &lower_file->f_pos);
+ header_pages = ((crypt_stat->header_extent_size
+ * crypt_stat->num_header_extents_at_front)
+ / PAGE_CACHE_SIZE);
+ memset(page_virt, 0, PAGE_CACHE_SIZE);
+ current_header_page = 1;
+ while (current_header_page < header_pages) {
+ ecryptfs_printk(KERN_DEBUG, "Calling lower_file->f_op->"
+ "write() w/ zero'd page; lower_file->f_pos = "
+ "[0x%.16x]\n", lower_file->f_pos);
+ lower_file->f_op->write(lower_file, (char __user *)page_virt,
+ PAGE_CACHE_SIZE, &lower_file->f_pos);
+ current_header_page++;
+ }
+ set_fs(oldfs);
+ ecryptfs_printk(KERN_DEBUG,
+ "Done writing key packet set to underlying file.\n");
+out_free:
+ kmem_cache_free(ecryptfs_header_cache_0, page_virt);
+out:
+ return rc;
+}
+
+static int parse_header_metadata(struct ecryptfs_crypt_stat *crypt_stat,
+ char *virt, int *bytes_read)
+{
+ int rc = 0;
+ u32 header_extent_size;
+ u16 num_header_extents_at_front;
+
+ memcpy(&header_extent_size, virt, 4);
+ header_extent_size = be32_to_cpu(header_extent_size);
+ virt += 4;
+ memcpy(&num_header_extents_at_front, virt, 2);
+ num_header_extents_at_front = be16_to_cpu(num_header_extents_at_front);
+ crypt_stat->header_extent_size = (int)header_extent_size;
+ crypt_stat->num_header_extents_at_front =
+ (int)num_header_extents_at_front;
+ (*bytes_read) = 6;
+ if ((crypt_stat->header_extent_size
+ * crypt_stat->num_header_extents_at_front)
+ < ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE) {
+ rc = -EINVAL;
+ ecryptfs_printk(KERN_WARNING, "Invalid header extent size: "
+ "[%d]\n", crypt_stat->header_extent_size);
+ }
+ return rc;
+}
+
+/**
+ * set_default_header_data
+ *
+ * For version 0 file format; this function is only for backwards
+ * compatibility for files created with the prior versions of
+ * eCryptfs.
+ */
+static void set_default_header_data(struct ecryptfs_crypt_stat *crypt_stat)
+{
+ crypt_stat->header_extent_size = 4096;
+ crypt_stat->num_header_extents_at_front = 1;
+}
+
+/**
+ * ecryptfs_read_headers_virt
+ *
+ * Read/parse the header data. The header format is detailed in the
+ * comment block for the ecryptfs_write_headers_virt() function.
+ *
+ * Returns zero on success
+ */
+static int ecryptfs_read_headers_virt(char *page_virt,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct dentry *ecryptfs_dentry)
+{
+ int rc = 0;
+ int offset;
+ int bytes_read;
+
+ ecryptfs_set_default_sizes(crypt_stat);
+ crypt_stat->mount_crypt_stat = &ecryptfs_superblock_to_private(
+ ecryptfs_dentry->d_sb)->mount_crypt_stat;
+ offset = ECRYPTFS_FILE_SIZE_BYTES;
+ rc = contains_ecryptfs_marker(page_virt + offset);
+ if (rc == 0) {
+ rc = -EINVAL;
+ goto out;
+ }
+ offset += MAGIC_ECRYPTFS_MARKER_SIZE_BYTES;
+ rc = ecryptfs_process_flags(crypt_stat, (page_virt + offset),
+ &bytes_read);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error processing flags\n");
+ goto out;
+ }
+ if (crypt_stat->file_version > ECRYPTFS_SUPPORTED_FILE_VERSION) {
+ ecryptfs_printk(KERN_WARNING, "File version is [%d]; only "
+ "file version [%d] is supported by this "
+ "version of eCryptfs\n",
+ crypt_stat->file_version,
+ ECRYPTFS_SUPPORTED_FILE_VERSION);
+ rc = -EINVAL;
+ goto out;
+ }
+ offset += bytes_read;
+ if (crypt_stat->file_version >= 1) {
+ rc = parse_header_metadata(crypt_stat, (page_virt + offset),
+ &bytes_read);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error reading header "
+ "metadata; rc = [%d]\n", rc);
+ }
+ offset += bytes_read;
+ } else
+ set_default_header_data(crypt_stat);
+ rc = ecryptfs_parse_packet_set(crypt_stat, (page_virt + offset),
+ ecryptfs_dentry);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_read_headers
+ *
+ * Returns zero if valid headers found and parsed; non-zero otherwise
+ */
+int ecryptfs_read_headers(struct dentry *ecryptfs_dentry,
+ struct file *lower_file)
+{
+ int rc = 0;
+ char *page_virt = NULL;
+ mm_segment_t oldfs;
+ ssize_t bytes_read;
+ struct ecryptfs_crypt_stat *crypt_stat =
+ &ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat;
+
+ /* Read the first page from the underlying file */
+ page_virt = kmem_cache_alloc(ecryptfs_header_cache_1, SLAB_USER);
+ if (!page_virt) {
+ rc = -ENOMEM;
+ ecryptfs_printk(KERN_ERR, "Unable to allocate page_virt\n");
+ goto out;
+ }
+ lower_file->f_pos = 0;
+ oldfs = get_fs();
+ set_fs(get_ds());
+ bytes_read = lower_file->f_op->read(lower_file,
+ (char __user *)page_virt,
+ ECRYPTFS_DEFAULT_EXTENT_SIZE,
+ &lower_file->f_pos);
+ set_fs(oldfs);
+ if (bytes_read != ECRYPTFS_DEFAULT_EXTENT_SIZE) {
+ rc = -EINVAL;
+ goto out;
+ }
+ rc = ecryptfs_read_headers_virt(page_virt, crypt_stat,
+ ecryptfs_dentry);
+ if (rc) {
+ ecryptfs_printk(KERN_DEBUG, "Valid eCryptfs headers not "
+ "found\n");
+ rc = -EINVAL;
+ }
+out:
+ if (page_virt) {
+ memset(page_virt, 0, PAGE_CACHE_SIZE);
+ kmem_cache_free(ecryptfs_header_cache_1, page_virt);
+ }
+ return rc;
+}
+
+/**
+ * ecryptfs_encode_filename - converts a plaintext file name to cipher text
+ * @crypt_stat: The crypt_stat struct associated with the file anem to encode
+ * @name: The plaintext name
+ * @length: The length of the plaintext
+ * @encoded_name: The encypted name
+ *
+ * Encrypts and encodes a filename into something that constitutes a
+ * valid filename for a filesystem, with printable characters.
+ *
+ * We assume that we have a properly initialized crypto context,
+ * pointed to by crypt_stat->tfm.
+ *
+ * TODO: Implement filename decoding and decryption here, in place of
+ * memcpy. We are keeping the framework around for now to (1)
+ * facilitate testing of the components needed to implement filename
+ * encryption and (2) to provide a code base from which other
+ * developers in the community can easily implement this feature.
+ *
+ * Returns the length of encoded filename; negative if error
+ */
+int
+ecryptfs_encode_filename(struct ecryptfs_crypt_stat *crypt_stat,
+ const char *name, int length, char **encoded_name)
+{
+ int error = 0;
+
+ (*encoded_name) = kmalloc(length + 2, GFP_KERNEL);
+ if (!(*encoded_name)) {
+ error = -ENOMEM;
+ goto out;
+ }
+ /* TODO: Filename encryption is a scheduled feature for a
+ * future version of eCryptfs. This function is here only for
+ * the purpose of providing a framework for other developers
+ * to easily implement filename encryption. Hint: Replace this
+ * memcpy() with a call to encrypt and encode the
+ * filename, the set the length accordingly. */
+ memcpy((void *)(*encoded_name), (void *)name, length);
+ (*encoded_name)[length] = '\0';
+ error = length + 1;
+out:
+ return error;
+}
+
+/**
+ * ecryptfs_decode_filename - converts the cipher text name to plaintext
+ * @crypt_stat: The crypt_stat struct associated with the file
+ * @name: The filename in cipher text
+ * @length: The length of the cipher text name
+ * @decrypted_name: The plaintext name
+ *
+ * Decodes and decrypts the filename.
+ *
+ * We assume that we have a properly initialized crypto context,
+ * pointed to by crypt_stat->tfm.
+ *
+ * TODO: Implement filename decoding and decryption here, in place of
+ * memcpy. We are keeping the framework around for now to (1)
+ * facilitate testing of the components needed to implement filename
+ * encryption and (2) to provide a code base from which other
+ * developers in the community can easily implement this feature.
+ *
+ * Returns the length of decoded filename; negative if error
+ */
+int
+ecryptfs_decode_filename(struct ecryptfs_crypt_stat *crypt_stat,
+ const char *name, int length, char **decrypted_name)
+{
+ int error = 0;
+
+ (*decrypted_name) = kmalloc(length + 2, GFP_KERNEL);
+ if (!(*decrypted_name)) {
+ error = -ENOMEM;
+ goto out;
+ }
+ /* TODO: Filename encryption is a scheduled feature for a
+ * future version of eCryptfs. This function is here only for
+ * the purpose of providing a framework for other developers
+ * to easily implement filename encryption. Hint: Replace this
+ * memcpy() with a call to decode and decrypt the
+ * filename, the set the length accordingly. */
+ memcpy((void *)(*decrypted_name), (void *)name, length);
+ (*decrypted_name)[length + 1] = '\0'; /* Only for convenience
+ * in printing out the
+ * string in debug
+ * messages */
+ error = length;
+out:
+ return error;
+}
+
+/**
+ * ecryptfs_process_cipher - Perform cipher initialization.
+ * @tfm: Crypto context set by this function
+ * @key_tfm: Crypto context for key material, set by this function
+ * @cipher_name: Name of the cipher.
+ * @key_size: Size of the key in bytes.
+ *
+ * Returns zero on success. Any crypto_tfm structs allocated here
+ * should be released by other functions, such as on a superblock put
+ * event, regardless of whether this function succeeds for fails.
+ */
+int
+ecryptfs_process_cipher(struct crypto_tfm **tfm, struct crypto_tfm **key_tfm,
+ char *cipher_name, size_t key_size)
+{
+ char dummy_key[ECRYPTFS_MAX_KEY_BYTES];
+ int rc;
+
+ *tfm = *key_tfm = NULL;
+ if (key_size > ECRYPTFS_MAX_KEY_BYTES) {
+ rc = -EINVAL;
+ printk(KERN_ERR "Requested key size is [%Zd] bytes; maximum "
+ "allowable is [%d]\n", key_size, ECRYPTFS_MAX_KEY_BYTES);
+ goto out;
+ }
+ *tfm = crypto_alloc_tfm(cipher_name, (ECRYPTFS_DEFAULT_CHAINING_MODE
+ | CRYPTO_TFM_REQ_WEAK_KEY));
+ if (!(*tfm)) {
+ rc = -EINVAL;
+ printk(KERN_ERR "Unable to allocate crypto cipher with name "
+ "[%s]\n", cipher_name);
+ goto out;
+ }
+ *key_tfm = crypto_alloc_tfm(cipher_name, CRYPTO_TFM_REQ_WEAK_KEY);
+ if (!(*key_tfm)) {
+ rc = -EINVAL;
+ printk(KERN_ERR "Unable to allocate crypto cipher with name "
+ "[%s]\n", cipher_name);
+ goto out;
+ }
+ if (key_size < crypto_tfm_alg_min_keysize(*tfm)) {
+ rc = -EINVAL;
+ printk(KERN_ERR "Request key size is [%Zd]; minimum key size "
+ "supported by cipher [%s] is [%d]\n", key_size,
+ cipher_name, crypto_tfm_alg_min_keysize(*tfm));
+ goto out;
+ }
+ if (key_size < crypto_tfm_alg_min_keysize(*key_tfm)) {
+ rc = -EINVAL;
+ printk(KERN_ERR "Request key size is [%Zd]; minimum key size "
+ "supported by cipher [%s] is [%d]\n", key_size,
+ cipher_name, crypto_tfm_alg_min_keysize(*key_tfm));
+ goto out;
+ }
+ if (key_size > crypto_tfm_alg_max_keysize(*tfm)) {
+ rc = -EINVAL;
+ printk(KERN_ERR "Request key size is [%Zd]; maximum key size "
+ "supported by cipher [%s] is [%d]\n", key_size,
+ cipher_name, crypto_tfm_alg_min_keysize(*tfm));
+ goto out;
+ }
+ if (key_size > crypto_tfm_alg_max_keysize(*key_tfm)) {
+ rc = -EINVAL;
+ printk(KERN_ERR "Request key size is [%Zd]; maximum key size "
+ "supported by cipher [%s] is [%d]\n", key_size,
+ cipher_name, crypto_tfm_alg_min_keysize(*key_tfm));
+ goto out;
+ }
+ get_random_bytes(dummy_key, key_size);
+ rc = crypto_cipher_setkey(*tfm, dummy_key, key_size);
+ if (rc) {
+ printk(KERN_ERR "Error attempting to set key of size [%Zd] for "
+ "cipher [%s]; rc = [%d]\n", key_size, cipher_name, rc);
+ rc = -EINVAL;
+ goto out;
+ }
+ rc = crypto_cipher_setkey(*key_tfm, dummy_key, key_size);
+ if (rc) {
+ printk(KERN_ERR "Error attempting to set key of size [%Zd] for "
+ "cipher [%s]; rc = [%d]\n", key_size, cipher_name, rc);
+ rc = -EINVAL;
+ goto out;
+ }
+out:
+ return rc;
+}
--- /dev/null
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ * Functions only useful for debugging.
+ *
+ * Copyright (C) 2006 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include "ecryptfs_kernel.h"
+
+/**
+ * ecryptfs_dump_auth_tok - debug function to print auth toks
+ *
+ * This function will print the contents of an ecryptfs authentication
+ * token.
+ */
+void ecryptfs_dump_auth_tok(struct ecryptfs_auth_tok *auth_tok)
+{
+ char salt[ECRYPTFS_SALT_SIZE * 2 + 1];
+ char sig[ECRYPTFS_SIG_SIZE_HEX + 1];
+
+ ecryptfs_printk(KERN_DEBUG, "Auth tok at mem loc [%p]:\n",
+ auth_tok);
+ if (ECRYPTFS_CHECK_FLAG(auth_tok->flags, ECRYPTFS_PRIVATE_KEY)) {
+ ecryptfs_printk(KERN_DEBUG, " * private key type\n");
+ ecryptfs_printk(KERN_DEBUG, " * (NO PRIVATE KEY SUPPORT "
+ "IN ECRYPTFS VERSION 0.1)\n");
+ } else {
+ ecryptfs_printk(KERN_DEBUG, " * passphrase type\n");
+ ecryptfs_to_hex(salt, auth_tok->token.password.salt,
+ ECRYPTFS_SALT_SIZE);
+ salt[ECRYPTFS_SALT_SIZE * 2] = '\0';
+ ecryptfs_printk(KERN_DEBUG, " * salt = [%s]\n", salt);
+ if (ECRYPTFS_CHECK_FLAG(auth_tok->token.password.flags,
+ ECRYPTFS_PERSISTENT_PASSWORD)) {
+ ecryptfs_printk(KERN_DEBUG, " * persistent\n");
+ }
+ memcpy(sig, auth_tok->token.password.signature,
+ ECRYPTFS_SIG_SIZE_HEX);
+ sig[ECRYPTFS_SIG_SIZE_HEX] = '\0';
+ ecryptfs_printk(KERN_DEBUG, " * signature = [%s]\n", sig);
+ }
+ ecryptfs_printk(KERN_DEBUG, " * session_key.flags = [0x%x]\n",
+ auth_tok->session_key.flags);
+ if (auth_tok->session_key.flags
+ & ECRYPTFS_USERSPACE_SHOULD_TRY_TO_DECRYPT)
+ ecryptfs_printk(KERN_DEBUG,
+ " * Userspace decrypt request set\n");
+ if (auth_tok->session_key.flags
+ & ECRYPTFS_USERSPACE_SHOULD_TRY_TO_ENCRYPT)
+ ecryptfs_printk(KERN_DEBUG,
+ " * Userspace encrypt request set\n");
+ if (auth_tok->session_key.flags & ECRYPTFS_CONTAINS_DECRYPTED_KEY) {
+ ecryptfs_printk(KERN_DEBUG, " * Contains decrypted key\n");
+ ecryptfs_printk(KERN_DEBUG,
+ " * session_key.decrypted_key_size = [0x%x]\n",
+ auth_tok->session_key.decrypted_key_size);
+ ecryptfs_printk(KERN_DEBUG, " * Decrypted session key "
+ "dump:\n");
+ if (ecryptfs_verbosity > 0)
+ ecryptfs_dump_hex(auth_tok->session_key.decrypted_key,
+ ECRYPTFS_DEFAULT_KEY_BYTES);
+ }
+ if (auth_tok->session_key.flags & ECRYPTFS_CONTAINS_ENCRYPTED_KEY) {
+ ecryptfs_printk(KERN_DEBUG, " * Contains encrypted key\n");
+ ecryptfs_printk(KERN_DEBUG,
+ " * session_key.encrypted_key_size = [0x%x]\n",
+ auth_tok->session_key.encrypted_key_size);
+ ecryptfs_printk(KERN_DEBUG, " * Encrypted session key "
+ "dump:\n");
+ if (ecryptfs_verbosity > 0)
+ ecryptfs_dump_hex(auth_tok->session_key.encrypted_key,
+ auth_tok->session_key.
+ encrypted_key_size);
+ }
+}
+
+/**
+ * ecryptfs_dump_hex - debug hex printer
+ * @data: string of bytes to be printed
+ * @bytes: number of bytes to print
+ *
+ * Dump hexadecimal representation of char array
+ */
+void ecryptfs_dump_hex(char *data, int bytes)
+{
+ int i = 0;
+ int add_newline = 1;
+
+ if (ecryptfs_verbosity < 1)
+ return;
+ if (bytes != 0) {
+ printk(KERN_DEBUG "0x%.2x.", (unsigned char)data[i]);
+ i++;
+ }
+ while (i < bytes) {
+ printk("0x%.2x.", (unsigned char)data[i]);
+ i++;
+ if (i % 16 == 0) {
+ printk("\n");
+ add_newline = 0;
+ } else
+ add_newline = 1;
+ }
+ if (add_newline)
+ printk("\n");
+}
+
--- /dev/null
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 1997-2003 Erez Zadok
+ * Copyright (C) 2001-2003 Stony Brook University
+ * Copyright (C) 2004-2006 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <linux/dcache.h>
+#include <linux/namei.h>
+#include "ecryptfs_kernel.h"
+
+/**
+ * ecryptfs_d_revalidate - revalidate an ecryptfs dentry
+ * @dentry: The ecryptfs dentry
+ * @nd: The associated nameidata
+ *
+ * Called when the VFS needs to revalidate a dentry. This
+ * is called whenever a name lookup finds a dentry in the
+ * dcache. Most filesystems leave this as NULL, because all their
+ * dentries in the dcache are valid.
+ *
+ * Returns 1 if valid, 0 otherwise.
+ *
+ */
+static int ecryptfs_d_revalidate(struct dentry *dentry, struct nameidata *nd)
+{
+ struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
+ struct dentry *dentry_save;
+ struct vfsmount *vfsmount_save;
+ int rc = 1;
+
+ if (!lower_dentry->d_op || !lower_dentry->d_op->d_revalidate)
+ goto out;
+ dentry_save = nd->dentry;
+ vfsmount_save = nd->mnt;
+ nd->dentry = lower_dentry;
+ nd->mnt = lower_mnt;
+ rc = lower_dentry->d_op->d_revalidate(lower_dentry, nd);
+ nd->dentry = dentry_save;
+ nd->mnt = vfsmount_save;
+out:
+ return rc;
+}
+
+struct kmem_cache *ecryptfs_dentry_info_cache;
+
+/**
+ * ecryptfs_d_release
+ * @dentry: The ecryptfs dentry
+ *
+ * Called when a dentry is really deallocated.
+ */
+static void ecryptfs_d_release(struct dentry *dentry)
+{
+ struct dentry *lower_dentry;
+
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ if (ecryptfs_dentry_to_private(dentry))
+ kmem_cache_free(ecryptfs_dentry_info_cache,
+ ecryptfs_dentry_to_private(dentry));
+ if (lower_dentry)
+ dput(lower_dentry);
+ return;
+}
+
+struct dentry_operations ecryptfs_dops = {
+ .d_revalidate = ecryptfs_d_revalidate,
+ .d_release = ecryptfs_d_release,
+};
--- /dev/null
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ * Kernel declarations.
+ *
+ * Copyright (C) 1997-2003 Erez Zadok
+ * Copyright (C) 2001-2003 Stony Brook University
+ * Copyright (C) 2004-2006 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#ifndef ECRYPTFS_KERNEL_H
+#define ECRYPTFS_KERNEL_H
+
+#include <keys/user-type.h>
+#include <linux/fs.h>
+#include <linux/scatterlist.h>
+
+/* Version verification for shared data structures w/ userspace */
+#define ECRYPTFS_VERSION_MAJOR 0x00
+#define ECRYPTFS_VERSION_MINOR 0x04
+#define ECRYPTFS_SUPPORTED_FILE_VERSION 0x01
+/* These flags indicate which features are supported by the kernel
+ * module; userspace tools such as the mount helper read
+ * ECRYPTFS_VERSIONING_MASK from a sysfs handle in order to determine
+ * how to behave. */
+#define ECRYPTFS_VERSIONING_PASSPHRASE 0x00000001
+#define ECRYPTFS_VERSIONING_PUBKEY 0x00000002
+#define ECRYPTFS_VERSIONING_PLAINTEXT_PASSTHROUGH 0x00000004
+#define ECRYPTFS_VERSIONING_POLICY 0x00000008
+#define ECRYPTFS_VERSIONING_MASK (ECRYPTFS_VERSIONING_PASSPHRASE \
+ | ECRYPTFS_VERSIONING_PLAINTEXT_PASSTHROUGH)
+
+#define ECRYPTFS_MAX_PASSWORD_LENGTH 64
+#define ECRYPTFS_MAX_PASSPHRASE_BYTES ECRYPTFS_MAX_PASSWORD_LENGTH
+#define ECRYPTFS_SALT_SIZE 8
+#define ECRYPTFS_SALT_SIZE_HEX (ECRYPTFS_SALT_SIZE*2)
+/* The original signature size is only for what is stored on disk; all
+ * in-memory representations are expanded hex, so it better adapted to
+ * be passed around or referenced on the command line */
+#define ECRYPTFS_SIG_SIZE 8
+#define ECRYPTFS_SIG_SIZE_HEX (ECRYPTFS_SIG_SIZE*2)
+#define ECRYPTFS_PASSWORD_SIG_SIZE ECRYPTFS_SIG_SIZE_HEX
+#define ECRYPTFS_MAX_KEY_BYTES 64
+#define ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES 512
+#define ECRYPTFS_DEFAULT_IV_BYTES 16
+#define ECRYPTFS_FILE_VERSION 0x01
+#define ECRYPTFS_DEFAULT_HEADER_EXTENT_SIZE 8192
+#define ECRYPTFS_DEFAULT_EXTENT_SIZE 4096
+#define ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE 8192
+
+#define RFC2440_CIPHER_DES3_EDE 0x02
+#define RFC2440_CIPHER_CAST_5 0x03
+#define RFC2440_CIPHER_BLOWFISH 0x04
+#define RFC2440_CIPHER_AES_128 0x07
+#define RFC2440_CIPHER_AES_192 0x08
+#define RFC2440_CIPHER_AES_256 0x09
+#define RFC2440_CIPHER_TWOFISH 0x0a
+#define RFC2440_CIPHER_CAST_6 0x0b
+
+#define ECRYPTFS_SET_FLAG(flag_bit_vector, flag) (flag_bit_vector |= (flag))
+#define ECRYPTFS_CLEAR_FLAG(flag_bit_vector, flag) (flag_bit_vector &= ~(flag))
+#define ECRYPTFS_CHECK_FLAG(flag_bit_vector, flag) (flag_bit_vector & (flag))
+
+/**
+ * For convenience, we may need to pass around the encrypted session
+ * key between kernel and userspace because the authentication token
+ * may not be extractable. For example, the TPM may not release the
+ * private key, instead requiring the encrypted data and returning the
+ * decrypted data.
+ */
+struct ecryptfs_session_key {
+#define ECRYPTFS_USERSPACE_SHOULD_TRY_TO_DECRYPT 0x00000001
+#define ECRYPTFS_USERSPACE_SHOULD_TRY_TO_ENCRYPT 0x00000002
+#define ECRYPTFS_CONTAINS_DECRYPTED_KEY 0x00000004
+#define ECRYPTFS_CONTAINS_ENCRYPTED_KEY 0x00000008
+ u32 flags;
+ u32 encrypted_key_size;
+ u32 decrypted_key_size;
+ u8 encrypted_key[ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES];
+ u8 decrypted_key[ECRYPTFS_MAX_KEY_BYTES];
+};
+
+struct ecryptfs_password {
+ u32 password_bytes;
+ s32 hash_algo;
+ u32 hash_iterations;
+ u32 session_key_encryption_key_bytes;
+#define ECRYPTFS_PERSISTENT_PASSWORD 0x01
+#define ECRYPTFS_SESSION_KEY_ENCRYPTION_KEY_SET 0x02
+ u32 flags;
+ /* Iterated-hash concatenation of salt and passphrase */
+ u8 session_key_encryption_key[ECRYPTFS_MAX_KEY_BYTES];
+ u8 signature[ECRYPTFS_PASSWORD_SIG_SIZE + 1];
+ /* Always in expanded hex */
+ u8 salt[ECRYPTFS_SALT_SIZE];
+};
+
+enum ecryptfs_token_types {ECRYPTFS_PASSWORD, ECRYPTFS_PRIVATE_KEY};
+
+/* May be a password or a private key */
+struct ecryptfs_auth_tok {
+ u16 version; /* 8-bit major and 8-bit minor */
+ u16 token_type;
+ u32 flags;
+ struct ecryptfs_session_key session_key;
+ u8 reserved[32];
+ union {
+ struct ecryptfs_password password;
+ /* Private key is in future eCryptfs releases */
+ } token;
+} __attribute__ ((packed));
+
+void ecryptfs_dump_auth_tok(struct ecryptfs_auth_tok *auth_tok);
+extern void ecryptfs_to_hex(char *dst, char *src, size_t src_size);
+extern void ecryptfs_from_hex(char *dst, char *src, int dst_size);
+
+struct ecryptfs_key_record {
+ unsigned char type;
+ size_t enc_key_size;
+ unsigned char sig[ECRYPTFS_SIG_SIZE];
+ unsigned char enc_key[ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES];
+};
+
+struct ecryptfs_auth_tok_list {
+ struct ecryptfs_auth_tok *auth_tok;
+ struct list_head list;
+};
+
+struct ecryptfs_crypt_stat;
+struct ecryptfs_mount_crypt_stat;
+
+struct ecryptfs_page_crypt_context {
+ struct page *page;
+#define ECRYPTFS_PREPARE_COMMIT_MODE 0
+#define ECRYPTFS_WRITEPAGE_MODE 1
+ unsigned int mode;
+ union {
+ struct file *lower_file;
+ struct writeback_control *wbc;
+ } param;
+};
+
+static inline struct ecryptfs_auth_tok *
+ecryptfs_get_key_payload_data(struct key *key)
+{
+ return (struct ecryptfs_auth_tok *)
+ (((struct user_key_payload*)key->payload.data)->data);
+}
+
+#define ECRYPTFS_SUPER_MAGIC 0xf15f
+#define ECRYPTFS_MAX_KEYSET_SIZE 1024
+#define ECRYPTFS_MAX_CIPHER_NAME_SIZE 32
+#define ECRYPTFS_MAX_NUM_ENC_KEYS 64
+#define ECRYPTFS_MAX_NUM_KEYSIGS 2 /* TODO: Make this a linked list */
+#define ECRYPTFS_MAX_IV_BYTES 16 /* 128 bits */
+#define ECRYPTFS_SALT_BYTES 2
+#define MAGIC_ECRYPTFS_MARKER 0x3c81b7f5
+#define MAGIC_ECRYPTFS_MARKER_SIZE_BYTES 8 /* 4*2 */
+#define ECRYPTFS_FILE_SIZE_BYTES 8
+#define ECRYPTFS_DEFAULT_CIPHER "aes"
+#define ECRYPTFS_DEFAULT_KEY_BYTES 16
+#define ECRYPTFS_DEFAULT_CHAINING_MODE CRYPTO_TFM_MODE_CBC
+#define ECRYPTFS_TAG_3_PACKET_TYPE 0x8C
+#define ECRYPTFS_TAG_11_PACKET_TYPE 0xED
+#define MD5_DIGEST_SIZE 16
+
+/**
+ * This is the primary struct associated with each encrypted file.
+ *
+ * TODO: cache align/pack?
+ */
+struct ecryptfs_crypt_stat {
+#define ECRYPTFS_STRUCT_INITIALIZED 0x00000001
+#define ECRYPTFS_POLICY_APPLIED 0x00000002
+#define ECRYPTFS_NEW_FILE 0x00000004
+#define ECRYPTFS_ENCRYPTED 0x00000008
+#define ECRYPTFS_SECURITY_WARNING 0x00000010
+#define ECRYPTFS_ENABLE_HMAC 0x00000020
+#define ECRYPTFS_ENCRYPT_IV_PAGES 0x00000040
+#define ECRYPTFS_KEY_VALID 0x00000080
+ u32 flags;
+ unsigned int file_version;
+ size_t iv_bytes;
+ size_t num_keysigs;
+ size_t header_extent_size;
+ size_t num_header_extents_at_front;
+ size_t extent_size; /* Data extent size; default is 4096 */
+ size_t key_size;
+ size_t extent_shift;
+ unsigned int extent_mask;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
+ struct crypto_tfm *tfm;
+ struct crypto_tfm *md5_tfm; /* Crypto context for generating
+ * the initialization vectors */
+ unsigned char cipher[ECRYPTFS_MAX_CIPHER_NAME_SIZE];
+ unsigned char key[ECRYPTFS_MAX_KEY_BYTES];
+ unsigned char root_iv[ECRYPTFS_MAX_IV_BYTES];
+ unsigned char keysigs[ECRYPTFS_MAX_NUM_KEYSIGS][ECRYPTFS_SIG_SIZE_HEX];
+ struct mutex cs_tfm_mutex;
+ struct mutex cs_md5_tfm_mutex;
+ struct mutex cs_mutex;
+};
+
+/* inode private data. */
+struct ecryptfs_inode_info {
+ struct inode vfs_inode;
+ struct inode *wii_inode;
+ struct ecryptfs_crypt_stat crypt_stat;
+};
+
+/* dentry private data. Each dentry must keep track of a lower
+ * vfsmount too. */
+struct ecryptfs_dentry_info {
+ struct dentry *wdi_dentry;
+ struct vfsmount *lower_mnt;
+ struct ecryptfs_crypt_stat *crypt_stat;
+};
+
+/**
+ * This struct is to enable a mount-wide passphrase/salt combo. This
+ * is more or less a stopgap to provide similar functionality to other
+ * crypto filesystems like EncFS or CFS until full policy support is
+ * implemented in eCryptfs.
+ */
+struct ecryptfs_mount_crypt_stat {
+ /* Pointers to memory we do not own, do not free these */
+#define ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED 0x00000001
+ u32 flags;
+ struct ecryptfs_auth_tok *global_auth_tok;
+ struct key *global_auth_tok_key;
+ size_t global_default_cipher_key_size;
+ struct crypto_tfm *global_key_tfm;
+ struct mutex global_key_tfm_mutex;
+ unsigned char global_default_cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE
+ + 1];
+ unsigned char global_auth_tok_sig[ECRYPTFS_SIG_SIZE_HEX + 1];
+};
+
+/* superblock private data. */
+struct ecryptfs_sb_info {
+ struct super_block *wsi_sb;
+ struct ecryptfs_mount_crypt_stat mount_crypt_stat;
+};
+
+/* file private data. */
+struct ecryptfs_file_info {
+ struct file *wfi_file;
+ struct ecryptfs_crypt_stat *crypt_stat;
+};
+
+/* auth_tok <=> encrypted_session_key mappings */
+struct ecryptfs_auth_tok_list_item {
+ unsigned char encrypted_session_key[ECRYPTFS_MAX_KEY_BYTES];
+ struct list_head list;
+ struct ecryptfs_auth_tok auth_tok;
+};
+
+static inline struct ecryptfs_file_info *
+ecryptfs_file_to_private(struct file *file)
+{
+ return (struct ecryptfs_file_info *)file->private_data;
+}
+
+static inline void
+ecryptfs_set_file_private(struct file *file,
+ struct ecryptfs_file_info *file_info)
+{
+ file->private_data = file_info;
+}
+
+static inline struct file *ecryptfs_file_to_lower(struct file *file)
+{
+ return ((struct ecryptfs_file_info *)file->private_data)->wfi_file;
+}
+
+static inline void
+ecryptfs_set_file_lower(struct file *file, struct file *lower_file)
+{
+ ((struct ecryptfs_file_info *)file->private_data)->wfi_file =
+ lower_file;
+}
+
+static inline struct ecryptfs_inode_info *
+ecryptfs_inode_to_private(struct inode *inode)
+{
+ return container_of(inode, struct ecryptfs_inode_info, vfs_inode);
+}
+
+static inline struct inode *ecryptfs_inode_to_lower(struct inode *inode)
+{
+ return ecryptfs_inode_to_private(inode)->wii_inode;
+}
+
+static inline void
+ecryptfs_set_inode_lower(struct inode *inode, struct inode *lower_inode)
+{
+ ecryptfs_inode_to_private(inode)->wii_inode = lower_inode;
+}
+
+static inline struct ecryptfs_sb_info *
+ecryptfs_superblock_to_private(struct super_block *sb)
+{
+ return (struct ecryptfs_sb_info *)sb->s_fs_info;
+}
+
+static inline void
+ecryptfs_set_superblock_private(struct super_block *sb,
+ struct ecryptfs_sb_info *sb_info)
+{
+ sb->s_fs_info = sb_info;
+}
+
+static inline struct super_block *
+ecryptfs_superblock_to_lower(struct super_block *sb)
+{
+ return ((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb;
+}
+
+static inline void
+ecryptfs_set_superblock_lower(struct super_block *sb,
+ struct super_block *lower_sb)
+{
+ ((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb = lower_sb;
+}
+
+static inline struct ecryptfs_dentry_info *
+ecryptfs_dentry_to_private(struct dentry *dentry)
+{
+ return (struct ecryptfs_dentry_info *)dentry->d_fsdata;
+}
+
+static inline void
+ecryptfs_set_dentry_private(struct dentry *dentry,
+ struct ecryptfs_dentry_info *dentry_info)
+{
+ dentry->d_fsdata = dentry_info;
+}
+
+static inline struct dentry *
+ecryptfs_dentry_to_lower(struct dentry *dentry)
+{
+ return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->wdi_dentry;
+}
+
+static inline void
+ecryptfs_set_dentry_lower(struct dentry *dentry, struct dentry *lower_dentry)
+{
+ ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->wdi_dentry =
+ lower_dentry;
+}
+
+static inline struct vfsmount *
+ecryptfs_dentry_to_lower_mnt(struct dentry *dentry)
+{
+ return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_mnt;
+}
+
+static inline void
+ecryptfs_set_dentry_lower_mnt(struct dentry *dentry, struct vfsmount *lower_mnt)
+{
+ ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_mnt =
+ lower_mnt;
+}
+
+#define ecryptfs_printk(type, fmt, arg...) \
+ __ecryptfs_printk(type "%s: " fmt, __FUNCTION__, ## arg);
+void __ecryptfs_printk(const char *fmt, ...);
+
+extern const struct file_operations ecryptfs_main_fops;
+extern const struct file_operations ecryptfs_dir_fops;
+extern struct inode_operations ecryptfs_main_iops;
+extern struct inode_operations ecryptfs_dir_iops;
+extern struct inode_operations ecryptfs_symlink_iops;
+extern struct super_operations ecryptfs_sops;
+extern struct dentry_operations ecryptfs_dops;
+extern struct address_space_operations ecryptfs_aops;
+extern int ecryptfs_verbosity;
+
+extern struct kmem_cache *ecryptfs_auth_tok_list_item_cache;
+extern struct kmem_cache *ecryptfs_file_info_cache;
+extern struct kmem_cache *ecryptfs_dentry_info_cache;
+extern struct kmem_cache *ecryptfs_inode_info_cache;
+extern struct kmem_cache *ecryptfs_sb_info_cache;
+extern struct kmem_cache *ecryptfs_header_cache_0;
+extern struct kmem_cache *ecryptfs_header_cache_1;
+extern struct kmem_cache *ecryptfs_header_cache_2;
+extern struct kmem_cache *ecryptfs_lower_page_cache;
+
+int ecryptfs_interpose(struct dentry *hidden_dentry,
+ struct dentry *this_dentry, struct super_block *sb,
+ int flag);
+int ecryptfs_fill_zeros(struct file *file, loff_t new_length);
+int ecryptfs_decode_filename(struct ecryptfs_crypt_stat *crypt_stat,
+ const char *name, int length,
+ char **decrypted_name);
+int ecryptfs_encode_filename(struct ecryptfs_crypt_stat *crypt_stat,
+ const char *name, int length,
+ char **encoded_name);
+struct dentry *ecryptfs_lower_dentry(struct dentry *this_dentry);
+void ecryptfs_copy_attr_atime(struct inode *dest, const struct inode *src);
+void ecryptfs_copy_attr_all(struct inode *dest, const struct inode *src);
+void ecryptfs_copy_inode_size(struct inode *dst, const struct inode *src);
+void ecryptfs_dump_hex(char *data, int bytes);
+int virt_to_scatterlist(const void *addr, int size, struct scatterlist *sg,
+ int sg_size);
+int ecryptfs_compute_root_iv(struct ecryptfs_crypt_stat *crypt_stat);
+void ecryptfs_rotate_iv(unsigned char *iv);
+void ecryptfs_init_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
+void ecryptfs_destruct_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
+void ecryptfs_destruct_mount_crypt_stat(
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat);
+int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat);
+int ecryptfs_write_inode_size_to_header(struct file *lower_file,
+ struct inode *lower_inode,
+ struct inode *inode);
+int ecryptfs_get_lower_page(struct page **lower_page, struct inode *lower_inode,
+ struct file *lower_file,
+ unsigned long lower_page_index, int byte_offset,
+ int region_bytes);
+int
+ecryptfs_commit_lower_page(struct page *lower_page, struct inode *lower_inode,
+ struct file *lower_file, int byte_offset,
+ int region_size);
+int ecryptfs_copy_page_to_lower(struct page *page, struct inode *lower_inode,
+ struct file *lower_file);
+int ecryptfs_do_readpage(struct file *file, struct page *page,
+ pgoff_t lower_page_index);
+int ecryptfs_grab_and_map_lower_page(struct page **lower_page,
+ char **lower_virt,
+ struct inode *lower_inode,
+ unsigned long lower_page_index);
+int ecryptfs_writepage_and_release_lower_page(struct page *lower_page,
+ struct inode *lower_inode,
+ struct writeback_control *wbc);
+int ecryptfs_encrypt_page(struct ecryptfs_page_crypt_context *ctx);
+int ecryptfs_decrypt_page(struct file *file, struct page *page);
+int ecryptfs_write_headers(struct dentry *ecryptfs_dentry,
+ struct file *lower_file);
+int ecryptfs_write_headers_virt(char *page_virt,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct dentry *ecryptfs_dentry);
+int ecryptfs_read_headers(struct dentry *ecryptfs_dentry,
+ struct file *lower_file);
+int ecryptfs_new_file_context(struct dentry *ecryptfs_dentry);
+int contains_ecryptfs_marker(char *data);
+int ecryptfs_read_header_region(char *data, struct dentry *dentry,
+ struct vfsmount *mnt);
+u16 ecryptfs_code_for_cipher_string(struct ecryptfs_crypt_stat *crypt_stat);
+int ecryptfs_cipher_code_to_string(char *str, u16 cipher_code);
+void ecryptfs_set_default_sizes(struct ecryptfs_crypt_stat *crypt_stat);
+int ecryptfs_generate_key_packet_set(char *dest_base,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct dentry *ecryptfs_dentry,
+ size_t *len, size_t max);
+int process_request_key_err(long err_code);
+int
+ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat,
+ unsigned char *src, struct dentry *ecryptfs_dentry);
+int ecryptfs_truncate(struct dentry *dentry, loff_t new_length);
+int
+ecryptfs_process_cipher(struct crypto_tfm **tfm, struct crypto_tfm **key_tfm,
+ char *cipher_name, size_t key_size);
+int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode);
+int ecryptfs_inode_set(struct inode *inode, void *lower_inode);
+void ecryptfs_init_inode(struct inode *inode, struct inode *lower_inode);
+
+#endif /* #ifndef ECRYPTFS_KERNEL_H */
--- /dev/null
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 1997-2004 Erez Zadok
+ * Copyright (C) 2001-2004 Stony Brook University
+ * Copyright (C) 2004-2006 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mhalcrow@us.ibm.com>
+ * Michael C. Thompson <mcthomps@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <linux/file.h>
+#include <linux/poll.h>
+#include <linux/mount.h>
+#include <linux/pagemap.h>
+#include <linux/security.h>
+#include <linux/smp_lock.h>
+#include <linux/compat.h>
+#include "ecryptfs_kernel.h"
+
+/**
+ * ecryptfs_llseek
+ * @file: File we are seeking in
+ * @offset: The offset to seek to
+ * @origin: 2 - offset from i_size; 1 - offset from f_pos
+ *
+ * Returns the position we have seeked to, or negative on error
+ */
+static loff_t ecryptfs_llseek(struct file *file, loff_t offset, int origin)
+{
+ loff_t rv;
+ loff_t new_end_pos;
+ int rc;
+ int expanding_file = 0;
+ struct inode *inode = file->f_mapping->host;
+
+ /* If our offset is past the end of our file, we're going to
+ * need to grow it so we have a valid length of 0's */
+ new_end_pos = offset;
+ switch (origin) {
+ case 2:
+ new_end_pos += i_size_read(inode);
+ expanding_file = 1;
+ break;
+ case 1:
+ new_end_pos += file->f_pos;
+ if (new_end_pos > i_size_read(inode)) {
+ ecryptfs_printk(KERN_DEBUG, "new_end_pos(=[0x%.16x]) "
+ "> i_size_read(inode)(=[0x%.16x])\n",
+ new_end_pos, i_size_read(inode));
+ expanding_file = 1;
+ }
+ break;
+ default:
+ if (new_end_pos > i_size_read(inode)) {
+ ecryptfs_printk(KERN_DEBUG, "new_end_pos(=[0x%.16x]) "
+ "> i_size_read(inode)(=[0x%.16x])\n",
+ new_end_pos, i_size_read(inode));
+ expanding_file = 1;
+ }
+ }
+ ecryptfs_printk(KERN_DEBUG, "new_end_pos = [0x%.16x]\n", new_end_pos);
+ if (expanding_file) {
+ rc = ecryptfs_truncate(file->f_dentry, new_end_pos);
+ if (rc) {
+ rv = rc;
+ ecryptfs_printk(KERN_ERR, "Error on attempt to "
+ "truncate to (higher) offset [0x%.16x];"
+ " rc = [%d]\n", new_end_pos, rc);
+ goto out;
+ }
+ }
+ rv = generic_file_llseek(file, offset, origin);
+out:
+ return rv;
+}
+
+/**
+ * ecryptfs_read_update_atime
+ *
+ * generic_file_read updates the atime of upper layer inode. But, it
+ * doesn't give us a chance to update the atime of the lower layer
+ * inode. This function is a wrapper to generic_file_read. It
+ * updates the atime of the lower level inode if generic_file_read
+ * returns without any errors. This is to be used only for file reads.
+ * The function to be used for directory reads is ecryptfs_read.
+ */
+static ssize_t ecryptfs_read_update_atime(struct kiocb *iocb,
+ const struct iovec *iov,
+ unsigned long nr_segs, loff_t pos)
+{
+ int rc;
+ struct dentry *lower_dentry;
+ struct vfsmount *lower_vfsmount;
+ struct file *file = iocb->ki_filp;
+
+ rc = generic_file_aio_read(iocb, iov, nr_segs, pos);
+ /*
+ * Even though this is a async interface, we need to wait
+ * for IO to finish to update atime
+ */
+ if (-EIOCBQUEUED == rc)
+ rc = wait_on_sync_kiocb(iocb);
+ if (rc >= 0) {
+ lower_dentry = ecryptfs_dentry_to_lower(file->f_dentry);
+ lower_vfsmount = ecryptfs_dentry_to_lower_mnt(file->f_dentry);
+ touch_atime(lower_vfsmount, lower_dentry);
+ }
+ return rc;
+}
+
+struct ecryptfs_getdents_callback {
+ void *dirent;
+ struct dentry *dentry;
+ filldir_t filldir;
+ int err;
+ int filldir_called;
+ int entries_written;
+};
+
+/* Inspired by generic filldir in fs/readir.c */
+static int
+ecryptfs_filldir(void *dirent, const char *name, int namelen, loff_t offset,
+ u64 ino, unsigned int d_type)
+{
+ struct ecryptfs_crypt_stat *crypt_stat;
+ struct ecryptfs_getdents_callback *buf =
+ (struct ecryptfs_getdents_callback *)dirent;
+ int rc;
+ int decoded_length;
+ char *decoded_name;
+
+ crypt_stat = ecryptfs_dentry_to_private(buf->dentry)->crypt_stat;
+ buf->filldir_called++;
+ decoded_length = ecryptfs_decode_filename(crypt_stat, name, namelen,
+ &decoded_name);
+ if (decoded_length < 0) {
+ rc = decoded_length;
+ goto out;
+ }
+ rc = buf->filldir(buf->dirent, decoded_name, decoded_length, offset,
+ ino, d_type);
+ kfree(decoded_name);
+ if (rc >= 0)
+ buf->entries_written++;
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_readdir
+ * @file: The ecryptfs file struct
+ * @dirent: Directory entry
+ * @filldir: The filldir callback function
+ */
+static int ecryptfs_readdir(struct file *file, void *dirent, filldir_t filldir)
+{
+ int rc;
+ struct file *lower_file;
+ struct inode *inode;
+ struct ecryptfs_getdents_callback buf;
+
+ lower_file = ecryptfs_file_to_lower(file);
+ lower_file->f_pos = file->f_pos;
+ inode = file->f_dentry->d_inode;
+ memset(&buf, 0, sizeof(buf));
+ buf.dirent = dirent;
+ buf.dentry = file->f_dentry;
+ buf.filldir = filldir;
+retry:
+ buf.filldir_called = 0;
+ buf.entries_written = 0;
+ buf.err = 0;
+ rc = vfs_readdir(lower_file, ecryptfs_filldir, (void *)&buf);
+ if (buf.err)
+ rc = buf.err;
+ if (buf.filldir_called && !buf.entries_written)
+ goto retry;
+ file->f_pos = lower_file->f_pos;
+ if (rc >= 0)
+ ecryptfs_copy_attr_atime(inode, lower_file->f_dentry->d_inode);
+ return rc;
+}
+
+struct kmem_cache *ecryptfs_file_info_cache;
+
+/**
+ * ecryptfs_open
+ * @inode: inode speciying file to open
+ * @file: Structure to return filled in
+ *
+ * Opens the file specified by inode.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int ecryptfs_open(struct inode *inode, struct file *file)
+{
+ int rc = 0;
+ struct ecryptfs_crypt_stat *crypt_stat = NULL;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
+ struct dentry *ecryptfs_dentry = file->f_dentry;
+ /* Private value of ecryptfs_dentry allocated in
+ * ecryptfs_lookup() */
+ struct dentry *lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
+ struct inode *lower_inode = NULL;
+ struct file *lower_file = NULL;
+ struct vfsmount *lower_mnt;
+ struct ecryptfs_file_info *file_info;
+ int lower_flags;
+
+ /* Released in ecryptfs_release or end of function if failure */
+ file_info = kmem_cache_alloc(ecryptfs_file_info_cache, SLAB_KERNEL);
+ ecryptfs_set_file_private(file, file_info);
+ if (!file_info) {
+ ecryptfs_printk(KERN_ERR,
+ "Error attempting to allocate memory\n");
+ rc = -ENOMEM;
+ goto out;
+ }
+ memset(file_info, 0, sizeof(*file_info));
+ lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
+ crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
+ mount_crypt_stat = &ecryptfs_superblock_to_private(
+ ecryptfs_dentry->d_sb)->mount_crypt_stat;
+ mutex_lock(&crypt_stat->cs_mutex);
+ if (!ECRYPTFS_CHECK_FLAG(crypt_stat->flags, ECRYPTFS_POLICY_APPLIED)) {
+ ecryptfs_printk(KERN_DEBUG, "Setting flags for stat...\n");
+ /* Policy code enabled in future release */
+ ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_POLICY_APPLIED);
+ ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED);
+ }
+ mutex_unlock(&crypt_stat->cs_mutex);
+ /* This mntget & dget is undone via fput when the file is released */
+ dget(lower_dentry);
+ lower_flags = file->f_flags;
+ if ((lower_flags & O_ACCMODE) == O_WRONLY)
+ lower_flags = (lower_flags & O_ACCMODE) | O_RDWR;
+ if (file->f_flags & O_APPEND)
+ lower_flags &= ~O_APPEND;
+ lower_mnt = ecryptfs_dentry_to_lower_mnt(ecryptfs_dentry);
+ mntget(lower_mnt);
+ /* Corresponding fput() in ecryptfs_release() */
+ lower_file = dentry_open(lower_dentry, lower_mnt, lower_flags);
+ if (IS_ERR(lower_file)) {
+ rc = PTR_ERR(lower_file);
+ ecryptfs_printk(KERN_ERR, "Error opening lower file\n");
+ goto out_puts;
+ }
+ ecryptfs_set_file_lower(file, lower_file);
+ /* Isn't this check the same as the one in lookup? */
+ lower_inode = lower_dentry->d_inode;
+ if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) {
+ ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
+ ECRYPTFS_CLEAR_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED);
+ rc = 0;
+ goto out;
+ }
+ mutex_lock(&crypt_stat->cs_mutex);
+ if (i_size_read(lower_inode) < ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE) {
+ if (!(mount_crypt_stat->flags
+ & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) {
+ rc = -EIO;
+ printk(KERN_WARNING "Attempt to read file that is "
+ "not in a valid eCryptfs format, and plaintext "
+ "passthrough mode is not enabled; returning "
+ "-EIO\n");
+ mutex_unlock(&crypt_stat->cs_mutex);
+ goto out_puts;
+ }
+ crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
+ rc = 0;
+ mutex_unlock(&crypt_stat->cs_mutex);
+ goto out;
+ } else if (!ECRYPTFS_CHECK_FLAG(crypt_stat->flags,
+ ECRYPTFS_POLICY_APPLIED)
+ || !ECRYPTFS_CHECK_FLAG(crypt_stat->flags,
+ ECRYPTFS_KEY_VALID)) {
+ rc = ecryptfs_read_headers(ecryptfs_dentry, lower_file);
+ if (rc) {
+ ecryptfs_printk(KERN_DEBUG,
+ "Valid headers not found\n");
+ if (!(mount_crypt_stat->flags
+ & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) {
+ rc = -EIO;
+ printk(KERN_WARNING "Attempt to read file that "
+ "is not in a valid eCryptfs format, "
+ "and plaintext passthrough mode is not "
+ "enabled; returning -EIO\n");
+ mutex_unlock(&crypt_stat->cs_mutex);
+ goto out_puts;
+ }
+ ECRYPTFS_CLEAR_FLAG(crypt_stat->flags,
+ ECRYPTFS_ENCRYPTED);
+ rc = 0;
+ mutex_unlock(&crypt_stat->cs_mutex);
+ goto out;
+ }
+ }
+ mutex_unlock(&crypt_stat->cs_mutex);
+ ecryptfs_printk(KERN_DEBUG, "inode w/ addr = [0x%p], i_ino = [0x%.16x] "
+ "size: [0x%.16x]\n", inode, inode->i_ino,
+ i_size_read(inode));
+ ecryptfs_set_file_lower(file, lower_file);
+ goto out;
+out_puts:
+ mntput(lower_mnt);
+ dput(lower_dentry);
+ kmem_cache_free(ecryptfs_file_info_cache,
+ ecryptfs_file_to_private(file));
+out:
+ return rc;
+}
+
+static int ecryptfs_flush(struct file *file, fl_owner_t td)
+{
+ int rc = 0;
+ struct file *lower_file = NULL;
+
+ lower_file = ecryptfs_file_to_lower(file);
+ if (lower_file->f_op && lower_file->f_op->flush)
+ rc = lower_file->f_op->flush(lower_file, td);
+ return rc;
+}
+
+static int ecryptfs_release(struct inode *inode, struct file *file)
+{
+ struct file *lower_file = ecryptfs_file_to_lower(file);
+ struct ecryptfs_file_info *file_info = ecryptfs_file_to_private(file);
+ struct inode *lower_inode = ecryptfs_inode_to_lower(inode);
+
+ fput(lower_file);
+ inode->i_blocks = lower_inode->i_blocks;
+ kmem_cache_free(ecryptfs_file_info_cache, file_info);
+ return 0;
+}
+
+static int
+ecryptfs_fsync(struct file *file, struct dentry *dentry, int datasync)
+{
+ struct file *lower_file = ecryptfs_file_to_lower(file);
+ struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ struct inode *lower_inode = lower_dentry->d_inode;
+ int rc = -EINVAL;
+
+ if (lower_inode->i_fop->fsync) {
+ mutex_lock(&lower_inode->i_mutex);
+ rc = lower_inode->i_fop->fsync(lower_file, lower_dentry,
+ datasync);
+ mutex_unlock(&lower_inode->i_mutex);
+ }
+ return rc;
+}
+
+static int ecryptfs_fasync(int fd, struct file *file, int flag)
+{
+ int rc = 0;
+ struct file *lower_file = NULL;
+
+ lower_file = ecryptfs_file_to_lower(file);
+ if (lower_file->f_op && lower_file->f_op->fasync)
+ rc = lower_file->f_op->fasync(fd, lower_file, flag);
+ return rc;
+}
+
+static ssize_t ecryptfs_sendfile(struct file *file, loff_t * ppos,
+ size_t count, read_actor_t actor, void *target)
+{
+ struct file *lower_file = NULL;
+ int rc = -EINVAL;
+
+ lower_file = ecryptfs_file_to_lower(file);
+ if (lower_file->f_op && lower_file->f_op->sendfile)
+ rc = lower_file->f_op->sendfile(lower_file, ppos, count,
+ actor, target);
+
+ return rc;
+}
+
+static int ecryptfs_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg);
+
+const struct file_operations ecryptfs_dir_fops = {
+ .readdir = ecryptfs_readdir,
+ .ioctl = ecryptfs_ioctl,
+ .mmap = generic_file_mmap,
+ .open = ecryptfs_open,
+ .flush = ecryptfs_flush,
+ .release = ecryptfs_release,
+ .fsync = ecryptfs_fsync,
+ .fasync = ecryptfs_fasync,
+ .sendfile = ecryptfs_sendfile,
+};
+
+const struct file_operations ecryptfs_main_fops = {
+ .llseek = ecryptfs_llseek,
+ .read = do_sync_read,
+ .aio_read = ecryptfs_read_update_atime,
+ .write = do_sync_write,
+ .aio_write = generic_file_aio_write,
+ .readdir = ecryptfs_readdir,
+ .ioctl = ecryptfs_ioctl,
+ .mmap = generic_file_mmap,
+ .open = ecryptfs_open,
+ .flush = ecryptfs_flush,
+ .release = ecryptfs_release,
+ .fsync = ecryptfs_fsync,
+ .fasync = ecryptfs_fasync,
+ .sendfile = ecryptfs_sendfile,
+};
+
+static int
+ecryptfs_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ int rc = 0;
+ struct file *lower_file = NULL;
+
+ if (ecryptfs_file_to_private(file))
+ lower_file = ecryptfs_file_to_lower(file);
+ if (lower_file && lower_file->f_op && lower_file->f_op->ioctl)
+ rc = lower_file->f_op->ioctl(ecryptfs_inode_to_lower(inode),
+ lower_file, cmd, arg);
+ else
+ rc = -ENOTTY;
+ return rc;
+}
--- /dev/null
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 1997-2004 Erez Zadok
+ * Copyright (C) 2001-2004 Stony Brook University
+ * Copyright (C) 2004-2006 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ * Michael C. Thompsion <mcthomps@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <linux/file.h>
+#include <linux/vmalloc.h>
+#include <linux/pagemap.h>
+#include <linux/dcache.h>
+#include <linux/namei.h>
+#include <linux/mount.h>
+#include <linux/crypto.h>
+#include "ecryptfs_kernel.h"
+
+static struct dentry *lock_parent(struct dentry *dentry)
+{
+ struct dentry *dir;
+
+ dir = dget(dentry->d_parent);
+ mutex_lock(&(dir->d_inode->i_mutex));
+ return dir;
+}
+
+static void unlock_parent(struct dentry *dentry)
+{
+ mutex_unlock(&(dentry->d_parent->d_inode->i_mutex));
+ dput(dentry->d_parent);
+}
+
+static void unlock_dir(struct dentry *dir)
+{
+ mutex_unlock(&dir->d_inode->i_mutex);
+ dput(dir);
+}
+
+void ecryptfs_copy_inode_size(struct inode *dst, const struct inode *src)
+{
+ i_size_write(dst, i_size_read((struct inode *)src));
+ dst->i_blocks = src->i_blocks;
+}
+
+void ecryptfs_copy_attr_atime(struct inode *dest, const struct inode *src)
+{
+ dest->i_atime = src->i_atime;
+}
+
+static void ecryptfs_copy_attr_times(struct inode *dest,
+ const struct inode *src)
+{
+ dest->i_atime = src->i_atime;
+ dest->i_mtime = src->i_mtime;
+ dest->i_ctime = src->i_ctime;
+}
+
+static void ecryptfs_copy_attr_timesizes(struct inode *dest,
+ const struct inode *src)
+{
+ dest->i_atime = src->i_atime;
+ dest->i_mtime = src->i_mtime;
+ dest->i_ctime = src->i_ctime;
+ ecryptfs_copy_inode_size(dest, src);
+}
+
+void ecryptfs_copy_attr_all(struct inode *dest, const struct inode *src)
+{
+ dest->i_mode = src->i_mode;
+ dest->i_nlink = src->i_nlink;
+ dest->i_uid = src->i_uid;
+ dest->i_gid = src->i_gid;
+ dest->i_rdev = src->i_rdev;
+ dest->i_atime = src->i_atime;
+ dest->i_mtime = src->i_mtime;
+ dest->i_ctime = src->i_ctime;
+ dest->i_blkbits = src->i_blkbits;
+ dest->i_flags = src->i_flags;
+}
+
+/**
+ * ecryptfs_create_underlying_file
+ * @lower_dir_inode: inode of the parent in the lower fs of the new file
+ * @lower_dentry: New file's dentry in the lower fs
+ * @ecryptfs_dentry: New file's dentry in ecryptfs
+ * @mode: The mode of the new file
+ * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
+ *
+ * Creates the file in the lower file system.
+ *
+ * Returns zero on success; non-zero on error condition
+ */
+static int
+ecryptfs_create_underlying_file(struct inode *lower_dir_inode,
+ struct dentry *dentry, int mode,
+ struct nameidata *nd)
+{
+ struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
+ struct dentry *dentry_save;
+ struct vfsmount *vfsmount_save;
+ int rc;
+
+ dentry_save = nd->dentry;
+ vfsmount_save = nd->mnt;
+ nd->dentry = lower_dentry;
+ nd->mnt = lower_mnt;
+ rc = vfs_create(lower_dir_inode, lower_dentry, mode, nd);
+ nd->dentry = dentry_save;
+ nd->mnt = vfsmount_save;
+ return rc;
+}
+
+/**
+ * ecryptfs_do_create
+ * @directory_inode: inode of the new file's dentry's parent in ecryptfs
+ * @ecryptfs_dentry: New file's dentry in ecryptfs
+ * @mode: The mode of the new file
+ * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
+ *
+ * Creates the underlying file and the eCryptfs inode which will link to
+ * it. It will also update the eCryptfs directory inode to mimic the
+ * stat of the lower directory inode.
+ *
+ * Returns zero on success; non-zero on error condition
+ */
+static int
+ecryptfs_do_create(struct inode *directory_inode,
+ struct dentry *ecryptfs_dentry, int mode,
+ struct nameidata *nd)
+{
+ int rc;
+ struct dentry *lower_dentry;
+ struct dentry *lower_dir_dentry;
+
+ lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
+ lower_dir_dentry = lock_parent(lower_dentry);
+ if (unlikely(IS_ERR(lower_dir_dentry))) {
+ ecryptfs_printk(KERN_ERR, "Error locking directory of "
+ "dentry\n");
+ rc = PTR_ERR(lower_dir_dentry);
+ goto out;
+ }
+ rc = ecryptfs_create_underlying_file(lower_dir_dentry->d_inode,
+ ecryptfs_dentry, mode, nd);
+ if (unlikely(rc)) {
+ ecryptfs_printk(KERN_ERR,
+ "Failure to create underlying file\n");
+ goto out_lock;
+ }
+ rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
+ directory_inode->i_sb, 0);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Failure in ecryptfs_interpose\n");
+ goto out_lock;
+ }
+ ecryptfs_copy_attr_timesizes(directory_inode,
+ lower_dir_dentry->d_inode);
+out_lock:
+ unlock_dir(lower_dir_dentry);
+out:
+ return rc;
+}
+
+/**
+ * grow_file
+ * @ecryptfs_dentry: the ecryptfs dentry
+ * @lower_file: The lower file
+ * @inode: The ecryptfs inode
+ * @lower_inode: The lower inode
+ *
+ * This is the code which will grow the file to its correct size.
+ */
+static int grow_file(struct dentry *ecryptfs_dentry, struct file *lower_file,
+ struct inode *inode, struct inode *lower_inode)
+{
+ int rc = 0;
+ struct file fake_file;
+ struct ecryptfs_file_info tmp_file_info;
+
+ memset(&fake_file, 0, sizeof(fake_file));
+ fake_file.f_dentry = ecryptfs_dentry;
+ memset(&tmp_file_info, 0, sizeof(tmp_file_info));
+ ecryptfs_set_file_private(&fake_file, &tmp_file_info);
+ ecryptfs_set_file_lower(&fake_file, lower_file);
+ rc = ecryptfs_fill_zeros(&fake_file, 1);
+ if (rc) {
+ ECRYPTFS_SET_FLAG(
+ ecryptfs_inode_to_private(inode)->crypt_stat.flags,
+ ECRYPTFS_SECURITY_WARNING);
+ ecryptfs_printk(KERN_WARNING, "Error attempting to fill zeros "
+ "in file; rc = [%d]\n", rc);
+ goto out;
+ }
+ i_size_write(inode, 0);
+ ecryptfs_write_inode_size_to_header(lower_file, lower_inode, inode);
+ ECRYPTFS_SET_FLAG(ecryptfs_inode_to_private(inode)->crypt_stat.flags,
+ ECRYPTFS_NEW_FILE);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_initialize_file
+ *
+ * Cause the file to be changed from a basic empty file to an ecryptfs
+ * file with a header and first data page.
+ *
+ * Returns zero on success
+ */
+static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry)
+{
+ int rc = 0;
+ int lower_flags;
+ struct ecryptfs_crypt_stat *crypt_stat;
+ struct dentry *lower_dentry;
+ struct dentry *tlower_dentry = NULL;
+ struct file *lower_file;
+ struct inode *inode, *lower_inode;
+ struct vfsmount *lower_mnt;
+
+ lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
+ ecryptfs_printk(KERN_DEBUG, "lower_dentry->d_name.name = [%s]\n",
+ lower_dentry->d_name.name);
+ inode = ecryptfs_dentry->d_inode;
+ crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
+ tlower_dentry = dget(lower_dentry);
+ if (!tlower_dentry) {
+ rc = -ENOMEM;
+ ecryptfs_printk(KERN_ERR, "Error dget'ing lower_dentry\n");
+ goto out;
+ }
+ lower_flags = ((O_CREAT | O_WRONLY | O_TRUNC) & O_ACCMODE) | O_RDWR;
+#if BITS_PER_LONG != 32
+ lower_flags |= O_LARGEFILE;
+#endif
+ lower_mnt = ecryptfs_dentry_to_lower_mnt(ecryptfs_dentry);
+ mntget(lower_mnt);
+ /* Corresponding fput() at end of this function */
+ lower_file = dentry_open(tlower_dentry, lower_mnt, lower_flags);
+ if (IS_ERR(lower_file)) {
+ rc = PTR_ERR(lower_file);
+ ecryptfs_printk(KERN_ERR,
+ "Error opening dentry; rc = [%i]\n", rc);
+ goto out;
+ }
+ /* fput(lower_file) should handle the puts if we do this */
+ lower_file->f_dentry = tlower_dentry;
+ lower_file->f_vfsmnt = lower_mnt;
+ lower_inode = tlower_dentry->d_inode;
+ if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) {
+ ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
+ ECRYPTFS_CLEAR_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED);
+ goto out_fput;
+ }
+ ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_NEW_FILE);
+ ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n");
+ rc = ecryptfs_new_file_context(ecryptfs_dentry);
+ if (rc) {
+ ecryptfs_printk(KERN_DEBUG, "Error creating new file "
+ "context\n");
+ goto out_fput;
+ }
+ rc = ecryptfs_write_headers(ecryptfs_dentry, lower_file);
+ if (rc) {
+ ecryptfs_printk(KERN_DEBUG, "Error writing headers\n");
+ goto out_fput;
+ }
+ rc = grow_file(ecryptfs_dentry, lower_file, inode, lower_inode);
+out_fput:
+ fput(lower_file);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_create
+ * @dir: The inode of the directory in which to create the file.
+ * @dentry: The eCryptfs dentry
+ * @mode: The mode of the new file.
+ * @nd: nameidata
+ *
+ * Creates a new file.
+ *
+ * Returns zero on success; non-zero on error condition
+ */
+static int
+ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry,
+ int mode, struct nameidata *nd)
+{
+ int rc;
+
+ rc = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode, nd);
+ if (unlikely(rc)) {
+ ecryptfs_printk(KERN_WARNING, "Failed to create file in"
+ "lower filesystem\n");
+ goto out;
+ }
+ /* At this point, a file exists on "disk"; we need to make sure
+ * that this on disk file is prepared to be an ecryptfs file */
+ rc = ecryptfs_initialize_file(ecryptfs_dentry);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_lookup
+ * @dir: inode
+ * @dentry: The dentry
+ * @nd: nameidata, may be NULL
+ *
+ * Find a file on disk. If the file does not exist, then we'll add it to the
+ * dentry cache and continue on to read it from the disk.
+ */
+static struct dentry *ecryptfs_lookup(struct inode *dir, struct dentry *dentry,
+ struct nameidata *nd)
+{
+ int rc = 0;
+ struct dentry *lower_dir_dentry;
+ struct dentry *lower_dentry;
+ struct vfsmount *lower_mnt;
+ struct dentry *tlower_dentry = NULL;
+ char *encoded_name;
+ unsigned int encoded_namelen;
+ struct ecryptfs_crypt_stat *crypt_stat = NULL;
+ char *page_virt = NULL;
+ struct inode *lower_inode;
+ u64 file_size;
+
+ lower_dir_dentry = ecryptfs_dentry_to_lower(dentry->d_parent);
+ dentry->d_op = &ecryptfs_dops;
+ if ((dentry->d_name.len == 1 && !strcmp(dentry->d_name.name, "."))
+ || (dentry->d_name.len == 2 && !strcmp(dentry->d_name.name, "..")))
+ goto out_drop;
+ encoded_namelen = ecryptfs_encode_filename(crypt_stat,
+ dentry->d_name.name,
+ dentry->d_name.len,
+ &encoded_name);
+ if (encoded_namelen < 0) {
+ rc = encoded_namelen;
+ goto out_drop;
+ }
+ ecryptfs_printk(KERN_DEBUG, "encoded_name = [%s]; encoded_namelen "
+ "= [%d]\n", encoded_name, encoded_namelen);
+ lower_dentry = lookup_one_len(encoded_name, lower_dir_dentry,
+ encoded_namelen - 1);
+ kfree(encoded_name);
+ lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(dentry->d_parent));
+ if (IS_ERR(lower_dentry)) {
+ ecryptfs_printk(KERN_ERR, "ERR from lower_dentry\n");
+ rc = PTR_ERR(lower_dentry);
+ goto out_drop;
+ }
+ ecryptfs_printk(KERN_DEBUG, "lower_dentry = [%p]; lower_dentry->"
+ "d_name.name = [%s]\n", lower_dentry,
+ lower_dentry->d_name.name);
+ lower_inode = lower_dentry->d_inode;
+ ecryptfs_copy_attr_atime(dir, lower_dir_dentry->d_inode);
+ BUG_ON(!atomic_read(&lower_dentry->d_count));
+ ecryptfs_set_dentry_private(dentry,
+ kmem_cache_alloc(ecryptfs_dentry_info_cache,
+ SLAB_KERNEL));
+ if (!ecryptfs_dentry_to_private(dentry)) {
+ rc = -ENOMEM;
+ ecryptfs_printk(KERN_ERR, "Out of memory whilst attempting "
+ "to allocate ecryptfs_dentry_info struct\n");
+ goto out_dput;
+ }
+ ecryptfs_set_dentry_lower(dentry, lower_dentry);
+ ecryptfs_set_dentry_lower_mnt(dentry, lower_mnt);
+ if (!lower_dentry->d_inode) {
+ /* We want to add because we couldn't find in lower */
+ d_add(dentry, NULL);
+ goto out;
+ }
+ rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 1);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error interposing\n");
+ goto out_dput;
+ }
+ if (S_ISDIR(lower_inode->i_mode)) {
+ ecryptfs_printk(KERN_DEBUG, "Is a directory; returning\n");
+ goto out;
+ }
+ if (S_ISLNK(lower_inode->i_mode)) {
+ ecryptfs_printk(KERN_DEBUG, "Is a symlink; returning\n");
+ goto out;
+ }
+ if (!nd) {
+ ecryptfs_printk(KERN_DEBUG, "We have a NULL nd, just leave"
+ "as we *think* we are about to unlink\n");
+ goto out;
+ }
+ tlower_dentry = dget(lower_dentry);
+ if (!tlower_dentry || IS_ERR(tlower_dentry)) {
+ rc = -ENOMEM;
+ ecryptfs_printk(KERN_ERR, "Cannot dget lower_dentry\n");
+ goto out_dput;
+ }
+ /* Released in this function */
+ page_virt =
+ (char *)kmem_cache_alloc(ecryptfs_header_cache_2,
+ SLAB_USER);
+ if (!page_virt) {
+ rc = -ENOMEM;
+ ecryptfs_printk(KERN_ERR,
+ "Cannot ecryptfs_kmalloc a page\n");
+ goto out_dput;
+ }
+ memset(page_virt, 0, PAGE_CACHE_SIZE);
+ rc = ecryptfs_read_header_region(page_virt, tlower_dentry, nd->mnt);
+ crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
+ if (!ECRYPTFS_CHECK_FLAG(crypt_stat->flags, ECRYPTFS_POLICY_APPLIED))
+ ecryptfs_set_default_sizes(crypt_stat);
+ if (rc) {
+ rc = 0;
+ ecryptfs_printk(KERN_WARNING, "Error reading header region;"
+ " assuming unencrypted\n");
+ } else {
+ if (!contains_ecryptfs_marker(page_virt
+ + ECRYPTFS_FILE_SIZE_BYTES)) {
+ kmem_cache_free(ecryptfs_header_cache_2, page_virt);
+ goto out;
+ }
+ memcpy(&file_size, page_virt, sizeof(file_size));
+ file_size = be64_to_cpu(file_size);
+ i_size_write(dentry->d_inode, (loff_t)file_size);
+ }
+ kmem_cache_free(ecryptfs_header_cache_2, page_virt);
+ goto out;
+
+out_dput:
+ dput(lower_dentry);
+ if (tlower_dentry)
+ dput(tlower_dentry);
+out_drop:
+ d_drop(dentry);
+out:
+ return ERR_PTR(rc);
+}
+
+static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
+ struct dentry *new_dentry)
+{
+ struct dentry *lower_old_dentry;
+ struct dentry *lower_new_dentry;
+ struct dentry *lower_dir_dentry;
+ u64 file_size_save;
+ int rc;
+
+ file_size_save = i_size_read(old_dentry->d_inode);
+ lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
+ lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
+ dget(lower_old_dentry);
+ dget(lower_new_dentry);
+ lower_dir_dentry = lock_parent(lower_new_dentry);
+ rc = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode,
+ lower_new_dentry);
+ if (rc || !lower_new_dentry->d_inode)
+ goto out_lock;
+ rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb, 0);
+ if (rc)
+ goto out_lock;
+ ecryptfs_copy_attr_timesizes(dir, lower_new_dentry->d_inode);
+ old_dentry->d_inode->i_nlink =
+ ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink;
+ i_size_write(new_dentry->d_inode, file_size_save);
+out_lock:
+ unlock_dir(lower_dir_dentry);
+ dput(lower_new_dentry);
+ dput(lower_old_dentry);
+ if (!new_dentry->d_inode)
+ d_drop(new_dentry);
+ return rc;
+}
+
+static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry)
+{
+ int rc = 0;
+ struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir);
+
+ lock_parent(lower_dentry);
+ rc = vfs_unlink(lower_dir_inode, lower_dentry);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error in vfs_unlink\n");
+ goto out_unlock;
+ }
+ ecryptfs_copy_attr_times(dir, lower_dir_inode);
+ dentry->d_inode->i_nlink =
+ ecryptfs_inode_to_lower(dentry->d_inode)->i_nlink;
+ dentry->d_inode->i_ctime = dir->i_ctime;
+out_unlock:
+ unlock_parent(lower_dentry);
+ return rc;
+}
+
+static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
+ const char *symname)
+{
+ int rc;
+ struct dentry *lower_dentry;
+ struct dentry *lower_dir_dentry;
+ umode_t mode;
+ char *encoded_symname;
+ unsigned int encoded_symlen;
+ struct ecryptfs_crypt_stat *crypt_stat = NULL;
+
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ dget(lower_dentry);
+ lower_dir_dentry = lock_parent(lower_dentry);
+ mode = S_IALLUGO;
+ encoded_symlen = ecryptfs_encode_filename(crypt_stat, symname,
+ strlen(symname),
+ &encoded_symname);
+ if (encoded_symlen < 0) {
+ rc = encoded_symlen;
+ goto out_lock;
+ }
+ rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry,
+ encoded_symname, mode);
+ kfree(encoded_symname);
+ if (rc || !lower_dentry->d_inode)
+ goto out_lock;
+ rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
+ if (rc)
+ goto out_lock;
+ ecryptfs_copy_attr_timesizes(dir, lower_dir_dentry->d_inode);
+out_lock:
+ unlock_dir(lower_dir_dentry);
+ dput(lower_dentry);
+ if (!dentry->d_inode)
+ d_drop(dentry);
+ return rc;
+}
+
+static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
+{
+ int rc;
+ struct dentry *lower_dentry;
+ struct dentry *lower_dir_dentry;
+
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ lower_dir_dentry = lock_parent(lower_dentry);
+ rc = vfs_mkdir(lower_dir_dentry->d_inode, lower_dentry, mode);
+ if (rc || !lower_dentry->d_inode)
+ goto out;
+ rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
+ if (rc)
+ goto out;
+ ecryptfs_copy_attr_timesizes(dir, lower_dir_dentry->d_inode);
+ dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
+out:
+ unlock_dir(lower_dir_dentry);
+ if (!dentry->d_inode)
+ d_drop(dentry);
+ return rc;
+}
+
+static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
+{
+ int rc = 0;
+ struct dentry *tdentry = NULL;
+ struct dentry *lower_dentry;
+ struct dentry *tlower_dentry = NULL;
+ struct dentry *lower_dir_dentry;
+
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ if (!(tdentry = dget(dentry))) {
+ rc = -EINVAL;
+ ecryptfs_printk(KERN_ERR, "Error dget'ing dentry [%p]\n",
+ dentry);
+ goto out;
+ }
+ lower_dir_dentry = lock_parent(lower_dentry);
+ if (!(tlower_dentry = dget(lower_dentry))) {
+ rc = -EINVAL;
+ ecryptfs_printk(KERN_ERR, "Error dget'ing lower_dentry "
+ "[%p]\n", lower_dentry);
+ goto out;
+ }
+ rc = vfs_rmdir(lower_dir_dentry->d_inode, lower_dentry);
+ if (!rc) {
+ d_delete(tlower_dentry);
+ tlower_dentry = NULL;
+ }
+ ecryptfs_copy_attr_times(dir, lower_dir_dentry->d_inode);
+ dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
+ unlock_dir(lower_dir_dentry);
+ if (!rc)
+ d_drop(dentry);
+out:
+ if (tdentry)
+ dput(tdentry);
+ if (tlower_dentry)
+ dput(tlower_dentry);
+ return rc;
+}
+
+static int
+ecryptfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
+{
+ int rc;
+ struct dentry *lower_dentry;
+ struct dentry *lower_dir_dentry;
+
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ lower_dir_dentry = lock_parent(lower_dentry);
+ rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev);
+ if (rc || !lower_dentry->d_inode)
+ goto out;
+ rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
+ if (rc)
+ goto out;
+ ecryptfs_copy_attr_timesizes(dir, lower_dir_dentry->d_inode);
+out:
+ unlock_dir(lower_dir_dentry);
+ if (!dentry->d_inode)
+ d_drop(dentry);
+ return rc;
+}
+
+static int
+ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry)
+{
+ int rc;
+ struct dentry *lower_old_dentry;
+ struct dentry *lower_new_dentry;
+ struct dentry *lower_old_dir_dentry;
+ struct dentry *lower_new_dir_dentry;
+
+ lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
+ lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
+ dget(lower_old_dentry);
+ dget(lower_new_dentry);
+ lower_old_dir_dentry = dget_parent(lower_old_dentry);
+ lower_new_dir_dentry = dget_parent(lower_new_dentry);
+ lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
+ rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
+ lower_new_dir_dentry->d_inode, lower_new_dentry);
+ if (rc)
+ goto out_lock;
+ ecryptfs_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode);
+ if (new_dir != old_dir)
+ ecryptfs_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode);
+out_lock:
+ unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
+ dput(lower_new_dentry);
+ dput(lower_old_dentry);
+ return rc;
+}
+
+static int
+ecryptfs_readlink(struct dentry *dentry, char __user * buf, int bufsiz)
+{
+ int rc;
+ struct dentry *lower_dentry;
+ char *decoded_name;
+ char *lower_buf;
+ mm_segment_t old_fs;
+ struct ecryptfs_crypt_stat *crypt_stat;
+
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ if (!lower_dentry->d_inode->i_op ||
+ !lower_dentry->d_inode->i_op->readlink) {
+ rc = -EINVAL;
+ goto out;
+ }
+ /* Released in this function */
+ lower_buf = kmalloc(bufsiz, GFP_KERNEL);
+ if (lower_buf == NULL) {
+ ecryptfs_printk(KERN_ERR, "Out of memory\n");
+ rc = -ENOMEM;
+ goto out;
+ }
+ old_fs = get_fs();
+ set_fs(get_ds());
+ ecryptfs_printk(KERN_DEBUG, "Calling readlink w/ "
+ "lower_dentry->d_name.name = [%s]\n",
+ lower_dentry->d_name.name);
+ rc = lower_dentry->d_inode->i_op->readlink(lower_dentry,
+ (char __user *)lower_buf,
+ bufsiz);
+ set_fs(old_fs);
+ if (rc >= 0) {
+ crypt_stat = NULL;
+ rc = ecryptfs_decode_filename(crypt_stat, lower_buf, rc,
+ &decoded_name);
+ if (rc == -ENOMEM)
+ goto out_free_lower_buf;
+ if (rc > 0) {
+ ecryptfs_printk(KERN_DEBUG, "Copying [%d] bytes "
+ "to userspace: [%*s]\n", rc,
+ decoded_name);
+ if (copy_to_user(buf, decoded_name, rc))
+ rc = -EFAULT;
+ }
+ kfree(decoded_name);
+ ecryptfs_copy_attr_atime(dentry->d_inode,
+ lower_dentry->d_inode);
+ }
+out_free_lower_buf:
+ kfree(lower_buf);
+out:
+ return rc;
+}
+
+static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+ char *buf;
+ int len = PAGE_SIZE, rc;
+ mm_segment_t old_fs;
+
+ /* Released in ecryptfs_put_link(); only release here on error */
+ buf = kmalloc(len, GFP_KERNEL);
+ if (!buf) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ old_fs = get_fs();
+ set_fs(get_ds());
+ ecryptfs_printk(KERN_DEBUG, "Calling readlink w/ "
+ "dentry->d_name.name = [%s]\n", dentry->d_name.name);
+ rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len);
+ buf[rc] = '\0';
+ set_fs(old_fs);
+ if (rc < 0)
+ goto out_free;
+ rc = 0;
+ nd_set_link(nd, buf);
+ goto out;
+out_free:
+ kfree(buf);
+out:
+ return ERR_PTR(rc);
+}
+
+static void
+ecryptfs_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr)
+{
+ /* Free the char* */
+ kfree(nd_get_link(nd));
+}
+
+/**
+ * upper_size_to_lower_size
+ * @crypt_stat: Crypt_stat associated with file
+ * @upper_size: Size of the upper file
+ *
+ * Calculate the requried size of the lower file based on the
+ * specified size of the upper file. This calculation is based on the
+ * number of headers in the underlying file and the extent size.
+ *
+ * Returns Calculated size of the lower file.
+ */
+static loff_t
+upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat,
+ loff_t upper_size)
+{
+ loff_t lower_size;
+
+ lower_size = ( crypt_stat->header_extent_size
+ * crypt_stat->num_header_extents_at_front );
+ if (upper_size != 0) {
+ loff_t num_extents;
+
+ num_extents = upper_size >> crypt_stat->extent_shift;
+ if (upper_size & ~crypt_stat->extent_mask)
+ num_extents++;
+ lower_size += (num_extents * crypt_stat->extent_size);
+ }
+ return lower_size;
+}
+
+/**
+ * ecryptfs_truncate
+ * @dentry: The ecryptfs layer dentry
+ * @new_length: The length to expand the file to
+ *
+ * Function to handle truncations modifying the size of the file. Note
+ * that the file sizes are interpolated. When expanding, we are simply
+ * writing strings of 0's out. When truncating, we need to modify the
+ * underlying file size according to the page index interpolations.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
+{
+ int rc = 0;
+ struct inode *inode = dentry->d_inode;
+ struct dentry *lower_dentry;
+ struct vfsmount *lower_mnt;
+ struct file fake_ecryptfs_file, *lower_file = NULL;
+ struct ecryptfs_crypt_stat *crypt_stat;
+ loff_t i_size = i_size_read(inode);
+ loff_t lower_size_before_truncate;
+ loff_t lower_size_after_truncate;
+
+ if (unlikely((new_length == i_size)))
+ goto out;
+ crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
+ /* Set up a fake ecryptfs file, this is used to interface with
+ * the file in the underlying filesystem so that the
+ * truncation has an effect there as well. */
+ memset(&fake_ecryptfs_file, 0, sizeof(fake_ecryptfs_file));
+ fake_ecryptfs_file.f_dentry = dentry;
+ /* Released at out_free: label */
+ ecryptfs_set_file_private(&fake_ecryptfs_file,
+ kmem_cache_alloc(ecryptfs_file_info_cache,
+ SLAB_KERNEL));
+ if (unlikely(!ecryptfs_file_to_private(&fake_ecryptfs_file))) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ /* This dget & mntget is released through fput at out_fput: */
+ dget(lower_dentry);
+ lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
+ mntget(lower_mnt);
+ lower_file = dentry_open(lower_dentry, lower_mnt, O_RDWR);
+ if (unlikely(IS_ERR(lower_file))) {
+ rc = PTR_ERR(lower_file);
+ goto out_free;
+ }
+ ecryptfs_set_file_lower(&fake_ecryptfs_file, lower_file);
+ /* Switch on growing or shrinking file */
+ if (new_length > i_size) {
+ rc = ecryptfs_fill_zeros(&fake_ecryptfs_file, new_length);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR,
+ "Problem with fill_zeros\n");
+ goto out_fput;
+ }
+ i_size_write(inode, new_length);
+ rc = ecryptfs_write_inode_size_to_header(lower_file,
+ lower_dentry->d_inode,
+ inode);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR,
+ "Problem with ecryptfs_write"
+ "_inode_size\n");
+ goto out_fput;
+ }
+ } else { /* new_length < i_size_read(inode) */
+ vmtruncate(inode, new_length);
+ ecryptfs_write_inode_size_to_header(lower_file,
+ lower_dentry->d_inode,
+ inode);
+ /* We are reducing the size of the ecryptfs file, and need to
+ * know if we need to reduce the size of the lower file. */
+ lower_size_before_truncate =
+ upper_size_to_lower_size(crypt_stat, i_size);
+ lower_size_after_truncate =
+ upper_size_to_lower_size(crypt_stat, new_length);
+ if (lower_size_after_truncate < lower_size_before_truncate)
+ vmtruncate(lower_dentry->d_inode,
+ lower_size_after_truncate);
+ }
+ /* Update the access times */
+ lower_dentry->d_inode->i_mtime = lower_dentry->d_inode->i_ctime
+ = CURRENT_TIME;
+ mark_inode_dirty_sync(inode);
+out_fput:
+ fput(lower_file);
+out_free:
+ if (ecryptfs_file_to_private(&fake_ecryptfs_file))
+ kmem_cache_free(ecryptfs_file_info_cache,
+ ecryptfs_file_to_private(&fake_ecryptfs_file));
+out:
+ return rc;
+}
+
+static int
+ecryptfs_permission(struct inode *inode, int mask, struct nameidata *nd)
+{
+ int rc;
+
+ if (nd) {
+ struct vfsmount *vfsmnt_save = nd->mnt;
+ struct dentry *dentry_save = nd->dentry;
+
+ nd->mnt = ecryptfs_dentry_to_lower_mnt(nd->dentry);
+ nd->dentry = ecryptfs_dentry_to_lower(nd->dentry);
+ rc = permission(ecryptfs_inode_to_lower(inode), mask, nd);
+ nd->mnt = vfsmnt_save;
+ nd->dentry = dentry_save;
+ } else
+ rc = permission(ecryptfs_inode_to_lower(inode), mask, NULL);
+ return rc;
+}
+
+/**
+ * ecryptfs_setattr
+ * @dentry: dentry handle to the inode to modify
+ * @ia: Structure with flags of what to change and values
+ *
+ * Updates the metadata of an inode. If the update is to the size
+ * i.e. truncation, then ecryptfs_truncate will handle the size modification
+ * of both the ecryptfs inode and the lower inode.
+ *
+ * All other metadata changes will be passed right to the lower filesystem,
+ * and we will just update our inode to look like the lower.
+ */
+static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
+{
+ int rc = 0;
+ struct dentry *lower_dentry;
+ struct inode *inode;
+ struct inode *lower_inode;
+ struct ecryptfs_crypt_stat *crypt_stat;
+
+ crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ inode = dentry->d_inode;
+ lower_inode = ecryptfs_inode_to_lower(inode);
+ if (ia->ia_valid & ATTR_SIZE) {
+ ecryptfs_printk(KERN_DEBUG,
+ "ia->ia_valid = [0x%x] ATTR_SIZE" " = [0x%x]\n",
+ ia->ia_valid, ATTR_SIZE);
+ rc = ecryptfs_truncate(dentry, ia->ia_size);
+ /* ecryptfs_truncate handles resizing of the lower file */
+ ia->ia_valid &= ~ATTR_SIZE;
+ ecryptfs_printk(KERN_DEBUG, "ia->ia_valid = [%x]\n",
+ ia->ia_valid);
+ if (rc < 0)
+ goto out;
+ }
+ rc = notify_change(lower_dentry, ia);
+out:
+ ecryptfs_copy_attr_all(inode, lower_inode);
+ return rc;
+}
+
+static int
+ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
+ size_t size, int flags)
+{
+ int rc = 0;
+ struct dentry *lower_dentry;
+
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ if (!lower_dentry->d_inode->i_op->setxattr) {
+ rc = -ENOSYS;
+ goto out;
+ }
+ mutex_lock(&lower_dentry->d_inode->i_mutex);
+ rc = lower_dentry->d_inode->i_op->setxattr(lower_dentry, name, value,
+ size, flags);
+ mutex_unlock(&lower_dentry->d_inode->i_mutex);
+out:
+ return rc;
+}
+
+static ssize_t
+ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value,
+ size_t size)
+{
+ int rc = 0;
+ struct dentry *lower_dentry;
+
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ if (!lower_dentry->d_inode->i_op->getxattr) {
+ rc = -ENOSYS;
+ goto out;
+ }
+ mutex_lock(&lower_dentry->d_inode->i_mutex);
+ rc = lower_dentry->d_inode->i_op->getxattr(lower_dentry, name, value,
+ size);
+ mutex_unlock(&lower_dentry->d_inode->i_mutex);
+out:
+ return rc;
+}
+
+static ssize_t
+ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size)
+{
+ int rc = 0;
+ struct dentry *lower_dentry;
+
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ if (!lower_dentry->d_inode->i_op->listxattr) {
+ rc = -ENOSYS;
+ goto out;
+ }
+ mutex_lock(&lower_dentry->d_inode->i_mutex);
+ rc = lower_dentry->d_inode->i_op->listxattr(lower_dentry, list, size);
+ mutex_unlock(&lower_dentry->d_inode->i_mutex);
+out:
+ return rc;
+}
+
+static int ecryptfs_removexattr(struct dentry *dentry, const char *name)
+{
+ int rc = 0;
+ struct dentry *lower_dentry;
+
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ if (!lower_dentry->d_inode->i_op->removexattr) {
+ rc = -ENOSYS;
+ goto out;
+ }
+ mutex_lock(&lower_dentry->d_inode->i_mutex);
+ rc = lower_dentry->d_inode->i_op->removexattr(lower_dentry, name);
+ mutex_unlock(&lower_dentry->d_inode->i_mutex);
+out:
+ return rc;
+}
+
+int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode)
+{
+ if ((ecryptfs_inode_to_lower(inode)
+ == (struct inode *)candidate_lower_inode))
+ return 1;
+ else
+ return 0;
+}
+
+int ecryptfs_inode_set(struct inode *inode, void *lower_inode)
+{
+ ecryptfs_init_inode(inode, (struct inode *)lower_inode);
+ return 0;
+}
+
+struct inode_operations ecryptfs_symlink_iops = {
+ .readlink = ecryptfs_readlink,
+ .follow_link = ecryptfs_follow_link,
+ .put_link = ecryptfs_put_link,
+ .permission = ecryptfs_permission,
+ .setattr = ecryptfs_setattr,
+ .setxattr = ecryptfs_setxattr,
+ .getxattr = ecryptfs_getxattr,
+ .listxattr = ecryptfs_listxattr,
+ .removexattr = ecryptfs_removexattr
+};
+
+struct inode_operations ecryptfs_dir_iops = {
+ .create = ecryptfs_create,
+ .lookup = ecryptfs_lookup,
+ .link = ecryptfs_link,
+ .unlink = ecryptfs_unlink,
+ .symlink = ecryptfs_symlink,
+ .mkdir = ecryptfs_mkdir,
+ .rmdir = ecryptfs_rmdir,
+ .mknod = ecryptfs_mknod,
+ .rename = ecryptfs_rename,
+ .permission = ecryptfs_permission,
+ .setattr = ecryptfs_setattr,
+ .setxattr = ecryptfs_setxattr,
+ .getxattr = ecryptfs_getxattr,
+ .listxattr = ecryptfs_listxattr,
+ .removexattr = ecryptfs_removexattr
+};
+
+struct inode_operations ecryptfs_main_iops = {
+ .permission = ecryptfs_permission,
+ .setattr = ecryptfs_setattr,
+ .setxattr = ecryptfs_setxattr,
+ .getxattr = ecryptfs_getxattr,
+ .listxattr = ecryptfs_listxattr,
+ .removexattr = ecryptfs_removexattr
+};
--- /dev/null
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ * In-kernel key management code. Includes functions to parse and
+ * write authentication token-related packets with the underlying
+ * file.
+ *
+ * Copyright (C) 2004-2006 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mhalcrow@us.ibm.com>
+ * Michael C. Thompson <mcthomps@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <linux/string.h>
+#include <linux/sched.h>
+#include <linux/syscalls.h>
+#include <linux/pagemap.h>
+#include <linux/key.h>
+#include <linux/random.h>
+#include <linux/crypto.h>
+#include <linux/scatterlist.h>
+#include "ecryptfs_kernel.h"
+
+/**
+ * request_key returned an error instead of a valid key address;
+ * determine the type of error, make appropriate log entries, and
+ * return an error code.
+ */
+int process_request_key_err(long err_code)
+{
+ int rc = 0;
+
+ switch (err_code) {
+ case ENOKEY:
+ ecryptfs_printk(KERN_WARNING, "No key\n");
+ rc = -ENOENT;
+ break;
+ case EKEYEXPIRED:
+ ecryptfs_printk(KERN_WARNING, "Key expired\n");
+ rc = -ETIME;
+ break;
+ case EKEYREVOKED:
+ ecryptfs_printk(KERN_WARNING, "Key revoked\n");
+ rc = -EINVAL;
+ break;
+ default:
+ ecryptfs_printk(KERN_WARNING, "Unknown error code: "
+ "[0x%.16x]\n", err_code);
+ rc = -EINVAL;
+ }
+ return rc;
+}
+
+static void wipe_auth_tok_list(struct list_head *auth_tok_list_head)
+{
+ struct list_head *walker;
+ struct ecryptfs_auth_tok_list_item *auth_tok_list_item;
+
+ walker = auth_tok_list_head->next;
+ while (walker != auth_tok_list_head) {
+ auth_tok_list_item =
+ list_entry(walker, struct ecryptfs_auth_tok_list_item,
+ list);
+ walker = auth_tok_list_item->list.next;
+ memset(auth_tok_list_item, 0,
+ sizeof(struct ecryptfs_auth_tok_list_item));
+ kmem_cache_free(ecryptfs_auth_tok_list_item_cache,
+ auth_tok_list_item);
+ }
+}
+
+struct kmem_cache *ecryptfs_auth_tok_list_item_cache;
+
+/**
+ * parse_packet_length
+ * @data: Pointer to memory containing length at offset
+ * @size: This function writes the decoded size to this memory
+ * address; zero on error
+ * @length_size: The number of bytes occupied by the encoded length
+ *
+ * Returns Zero on success
+ */
+static int parse_packet_length(unsigned char *data, size_t *size,
+ size_t *length_size)
+{
+ int rc = 0;
+
+ (*length_size) = 0;
+ (*size) = 0;
+ if (data[0] < 192) {
+ /* One-byte length */
+ (*size) = data[0];
+ (*length_size) = 1;
+ } else if (data[0] < 224) {
+ /* Two-byte length */
+ (*size) = ((data[0] - 192) * 256);
+ (*size) += (data[1] + 192);
+ (*length_size) = 2;
+ } else if (data[0] == 255) {
+ /* Five-byte length; we're not supposed to see this */
+ ecryptfs_printk(KERN_ERR, "Five-byte packet length not "
+ "supported\n");
+ rc = -EINVAL;
+ goto out;
+ } else {
+ ecryptfs_printk(KERN_ERR, "Error parsing packet length\n");
+ rc = -EINVAL;
+ goto out;
+ }
+out:
+ return rc;
+}
+
+/**
+ * write_packet_length
+ * @dest: The byte array target into which to write the
+ * length. Must have at least 5 bytes allocated.
+ * @size: The length to write.
+ * @packet_size_length: The number of bytes used to encode the
+ * packet length is written to this address.
+ *
+ * Returns zero on success; non-zero on error.
+ */
+static int write_packet_length(char *dest, size_t size,
+ size_t *packet_size_length)
+{
+ int rc = 0;
+
+ if (size < 192) {
+ dest[0] = size;
+ (*packet_size_length) = 1;
+ } else if (size < 65536) {
+ dest[0] = (((size - 192) / 256) + 192);
+ dest[1] = ((size - 192) % 256);
+ (*packet_size_length) = 2;
+ } else {
+ rc = -EINVAL;
+ ecryptfs_printk(KERN_WARNING,
+ "Unsupported packet size: [%d]\n", size);
+ }
+ return rc;
+}
+
+/**
+ * parse_tag_3_packet
+ * @crypt_stat: The cryptographic context to modify based on packet
+ * contents.
+ * @data: The raw bytes of the packet.
+ * @auth_tok_list: eCryptfs parses packets into authentication tokens;
+ * a new authentication token will be placed at the end
+ * of this list for this packet.
+ * @new_auth_tok: Pointer to a pointer to memory that this function
+ * allocates; sets the memory address of the pointer to
+ * NULL on error. This object is added to the
+ * auth_tok_list.
+ * @packet_size: This function writes the size of the parsed packet
+ * into this memory location; zero on error.
+ * @max_packet_size: maximum number of bytes to parse
+ *
+ * Returns zero on success; non-zero on error.
+ */
+static int
+parse_tag_3_packet(struct ecryptfs_crypt_stat *crypt_stat,
+ unsigned char *data, struct list_head *auth_tok_list,
+ struct ecryptfs_auth_tok **new_auth_tok,
+ size_t *packet_size, size_t max_packet_size)
+{
+ int rc = 0;
+ size_t body_size;
+ struct ecryptfs_auth_tok_list_item *auth_tok_list_item;
+ size_t length_size;
+
+ (*packet_size) = 0;
+ (*new_auth_tok) = NULL;
+
+ /* we check that:
+ * one byte for the Tag 3 ID flag
+ * two bytes for the body size
+ * do not exceed the maximum_packet_size
+ */
+ if (unlikely((*packet_size) + 3 > max_packet_size)) {
+ ecryptfs_printk(KERN_ERR, "Packet size exceeds max\n");
+ rc = -EINVAL;
+ goto out;
+ }
+
+ /* check for Tag 3 identifyer - one byte */
+ if (data[(*packet_size)++] != ECRYPTFS_TAG_3_PACKET_TYPE) {
+ ecryptfs_printk(KERN_ERR, "Enter w/ first byte != 0x%.2x\n",
+ ECRYPTFS_TAG_3_PACKET_TYPE);
+ rc = -EINVAL;
+ goto out;
+ }
+ /* Released: wipe_auth_tok_list called in ecryptfs_parse_packet_set or
+ * at end of function upon failure */
+ auth_tok_list_item =
+ kmem_cache_alloc(ecryptfs_auth_tok_list_item_cache, SLAB_KERNEL);
+ if (!auth_tok_list_item) {
+ ecryptfs_printk(KERN_ERR, "Unable to allocate memory\n");
+ rc = -ENOMEM;
+ goto out;
+ }
+ memset(auth_tok_list_item, 0,
+ sizeof(struct ecryptfs_auth_tok_list_item));
+ (*new_auth_tok) = &auth_tok_list_item->auth_tok;
+
+ /* check for body size - one to two bytes */
+ rc = parse_packet_length(&data[(*packet_size)], &body_size,
+ &length_size);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error parsing packet length; "
+ "rc = [%d]\n", rc);
+ goto out_free;
+ }
+ if (unlikely(body_size < (0x05 + ECRYPTFS_SALT_SIZE))) {
+ ecryptfs_printk(KERN_WARNING, "Invalid body size ([%d])\n",
+ body_size);
+ rc = -EINVAL;
+ goto out_free;
+ }
+ (*packet_size) += length_size;
+
+ /* now we know the length of the remainting Tag 3 packet size:
+ * 5 fix bytes for: version string, cipher, S2K ID, hash algo,
+ * number of hash iterations
+ * ECRYPTFS_SALT_SIZE bytes for salt
+ * body_size bytes minus the stuff above is the encrypted key size
+ */
+ if (unlikely((*packet_size) + body_size > max_packet_size)) {
+ ecryptfs_printk(KERN_ERR, "Packet size exceeds max\n");
+ rc = -EINVAL;
+ goto out_free;
+ }
+
+ /* There are 5 characters of additional information in the
+ * packet */
+ (*new_auth_tok)->session_key.encrypted_key_size =
+ body_size - (0x05 + ECRYPTFS_SALT_SIZE);
+ ecryptfs_printk(KERN_DEBUG, "Encrypted key size = [%d]\n",
+ (*new_auth_tok)->session_key.encrypted_key_size);
+
+ /* Version 4 (from RFC2440) - one byte */
+ if (unlikely(data[(*packet_size)++] != 0x04)) {
+ ecryptfs_printk(KERN_DEBUG, "Unknown version number "
+ "[%d]\n", data[(*packet_size) - 1]);
+ rc = -EINVAL;
+ goto out_free;
+ }
+
+ /* cipher - one byte */
+ ecryptfs_cipher_code_to_string(crypt_stat->cipher,
+ (u16)data[(*packet_size)]);
+ /* A little extra work to differentiate among the AES key
+ * sizes; see RFC2440 */
+ switch(data[(*packet_size)++]) {
+ case RFC2440_CIPHER_AES_192:
+ crypt_stat->key_size = 24;
+ break;
+ default:
+ crypt_stat->key_size =
+ (*new_auth_tok)->session_key.encrypted_key_size;
+ }
+ ecryptfs_init_crypt_ctx(crypt_stat);
+ /* S2K identifier 3 (from RFC2440) */
+ if (unlikely(data[(*packet_size)++] != 0x03)) {
+ ecryptfs_printk(KERN_ERR, "Only S2K ID 3 is currently "
+ "supported\n");
+ rc = -ENOSYS;
+ goto out_free;
+ }
+
+ /* TODO: finish the hash mapping */
+ /* hash algorithm - one byte */
+ switch (data[(*packet_size)++]) {
+ case 0x01: /* See RFC2440 for these numbers and their mappings */
+ /* Choose MD5 */
+ /* salt - ECRYPTFS_SALT_SIZE bytes */
+ memcpy((*new_auth_tok)->token.password.salt,
+ &data[(*packet_size)], ECRYPTFS_SALT_SIZE);
+ (*packet_size) += ECRYPTFS_SALT_SIZE;
+
+ /* This conversion was taken straight from RFC2440 */
+ /* number of hash iterations - one byte */
+ (*new_auth_tok)->token.password.hash_iterations =
+ ((u32) 16 + (data[(*packet_size)] & 15))
+ << ((data[(*packet_size)] >> 4) + 6);
+ (*packet_size)++;
+
+ /* encrypted session key -
+ * (body_size-5-ECRYPTFS_SALT_SIZE) bytes */
+ memcpy((*new_auth_tok)->session_key.encrypted_key,
+ &data[(*packet_size)],
+ (*new_auth_tok)->session_key.encrypted_key_size);
+ (*packet_size) +=
+ (*new_auth_tok)->session_key.encrypted_key_size;
+ (*new_auth_tok)->session_key.flags &=
+ ~ECRYPTFS_CONTAINS_DECRYPTED_KEY;
+ (*new_auth_tok)->session_key.flags |=
+ ECRYPTFS_CONTAINS_ENCRYPTED_KEY;
+ (*new_auth_tok)->token.password.hash_algo = 0x01;
+ break;
+ default:
+ ecryptfs_printk(KERN_ERR, "Unsupported hash algorithm: "
+ "[%d]\n", data[(*packet_size) - 1]);
+ rc = -ENOSYS;
+ goto out_free;
+ }
+ (*new_auth_tok)->token_type = ECRYPTFS_PASSWORD;
+ /* TODO: Parametarize; we might actually want userspace to
+ * decrypt the session key. */
+ ECRYPTFS_CLEAR_FLAG((*new_auth_tok)->session_key.flags,
+ ECRYPTFS_USERSPACE_SHOULD_TRY_TO_DECRYPT);
+ ECRYPTFS_CLEAR_FLAG((*new_auth_tok)->session_key.flags,
+ ECRYPTFS_USERSPACE_SHOULD_TRY_TO_ENCRYPT);
+ list_add(&auth_tok_list_item->list, auth_tok_list);
+ goto out;
+out_free:
+ (*new_auth_tok) = NULL;
+ memset(auth_tok_list_item, 0,
+ sizeof(struct ecryptfs_auth_tok_list_item));
+ kmem_cache_free(ecryptfs_auth_tok_list_item_cache,
+ auth_tok_list_item);
+out:
+ if (rc)
+ (*packet_size) = 0;
+ return rc;
+}
+
+/**
+ * parse_tag_11_packet
+ * @data: The raw bytes of the packet
+ * @contents: This function writes the data contents of the literal
+ * packet into this memory location
+ * @max_contents_bytes: The maximum number of bytes that this function
+ * is allowed to write into contents
+ * @tag_11_contents_size: This function writes the size of the parsed
+ * contents into this memory location; zero on
+ * error
+ * @packet_size: This function writes the size of the parsed packet
+ * into this memory location; zero on error
+ * @max_packet_size: maximum number of bytes to parse
+ *
+ * Returns zero on success; non-zero on error.
+ */
+static int
+parse_tag_11_packet(unsigned char *data, unsigned char *contents,
+ size_t max_contents_bytes, size_t *tag_11_contents_size,
+ size_t *packet_size, size_t max_packet_size)
+{
+ int rc = 0;
+ size_t body_size;
+ size_t length_size;
+
+ (*packet_size) = 0;
+ (*tag_11_contents_size) = 0;
+
+ /* check that:
+ * one byte for the Tag 11 ID flag
+ * two bytes for the Tag 11 length
+ * do not exceed the maximum_packet_size
+ */
+ if (unlikely((*packet_size) + 3 > max_packet_size)) {
+ ecryptfs_printk(KERN_ERR, "Packet size exceeds max\n");
+ rc = -EINVAL;
+ goto out;
+ }
+
+ /* check for Tag 11 identifyer - one byte */
+ if (data[(*packet_size)++] != ECRYPTFS_TAG_11_PACKET_TYPE) {
+ ecryptfs_printk(KERN_WARNING,
+ "Invalid tag 11 packet format\n");
+ rc = -EINVAL;
+ goto out;
+ }
+
+ /* get Tag 11 content length - one or two bytes */
+ rc = parse_packet_length(&data[(*packet_size)], &body_size,
+ &length_size);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING,
+ "Invalid tag 11 packet format\n");
+ goto out;
+ }
+ (*packet_size) += length_size;
+
+ if (body_size < 13) {
+ ecryptfs_printk(KERN_WARNING, "Invalid body size ([%d])\n",
+ body_size);
+ rc = -EINVAL;
+ goto out;
+ }
+ /* We have 13 bytes of surrounding packet values */
+ (*tag_11_contents_size) = (body_size - 13);
+
+ /* now we know the length of the remainting Tag 11 packet size:
+ * 14 fix bytes for: special flag one, special flag two,
+ * 12 skipped bytes
+ * body_size bytes minus the stuff above is the Tag 11 content
+ */
+ /* FIXME why is the body size one byte smaller than the actual
+ * size of the body?
+ * this seems to be an error here as well as in
+ * write_tag_11_packet() */
+ if (unlikely((*packet_size) + body_size + 1 > max_packet_size)) {
+ ecryptfs_printk(KERN_ERR, "Packet size exceeds max\n");
+ rc = -EINVAL;
+ goto out;
+ }
+
+ /* special flag one - one byte */
+ if (data[(*packet_size)++] != 0x62) {
+ ecryptfs_printk(KERN_WARNING, "Unrecognizable packet\n");
+ rc = -EINVAL;
+ goto out;
+ }
+
+ /* special flag two - one byte */
+ if (data[(*packet_size)++] != 0x08) {
+ ecryptfs_printk(KERN_WARNING, "Unrecognizable packet\n");
+ rc = -EINVAL;
+ goto out;
+ }
+
+ /* skip the next 12 bytes */
+ (*packet_size) += 12; /* We don't care about the filename or
+ * the timestamp */
+
+ /* get the Tag 11 contents - tag_11_contents_size bytes */
+ memcpy(contents, &data[(*packet_size)], (*tag_11_contents_size));
+ (*packet_size) += (*tag_11_contents_size);
+
+out:
+ if (rc) {
+ (*packet_size) = 0;
+ (*tag_11_contents_size) = 0;
+ }
+ return rc;
+}
+
+/**
+ * decrypt_session_key - Decrypt the session key with the given auth_tok.
+ *
+ * Returns Zero on success; non-zero error otherwise.
+ */
+static int decrypt_session_key(struct ecryptfs_auth_tok *auth_tok,
+ struct ecryptfs_crypt_stat *crypt_stat)
+{
+ int rc = 0;
+ struct ecryptfs_password *password_s_ptr;
+ struct crypto_tfm *tfm = NULL;
+ struct scatterlist src_sg[2], dst_sg[2];
+ struct mutex *tfm_mutex = NULL;
+ /* TODO: Use virt_to_scatterlist for these */
+ char *encrypted_session_key;
+ char *session_key;
+
+ password_s_ptr = &auth_tok->token.password;
+ if (ECRYPTFS_CHECK_FLAG(password_s_ptr->flags,
+ ECRYPTFS_SESSION_KEY_ENCRYPTION_KEY_SET))
+ ecryptfs_printk(KERN_DEBUG, "Session key encryption key "
+ "set; skipping key generation\n");
+ ecryptfs_printk(KERN_DEBUG, "Session key encryption key (size [%d])"
+ ":\n",
+ password_s_ptr->session_key_encryption_key_bytes);
+ if (ecryptfs_verbosity > 0)
+ ecryptfs_dump_hex(password_s_ptr->session_key_encryption_key,
+ password_s_ptr->
+ session_key_encryption_key_bytes);
+ if (!strcmp(crypt_stat->cipher,
+ crypt_stat->mount_crypt_stat->global_default_cipher_name)
+ && crypt_stat->mount_crypt_stat->global_key_tfm) {
+ tfm = crypt_stat->mount_crypt_stat->global_key_tfm;
+ tfm_mutex = &crypt_stat->mount_crypt_stat->global_key_tfm_mutex;
+ } else {
+ tfm = crypto_alloc_tfm(crypt_stat->cipher,
+ CRYPTO_TFM_REQ_WEAK_KEY);
+ if (!tfm) {
+ printk(KERN_ERR "Error allocating crypto context\n");
+ rc = -ENOMEM;
+ goto out;
+ }
+ }
+ if (password_s_ptr->session_key_encryption_key_bytes
+ < crypto_tfm_alg_min_keysize(tfm)) {
+ printk(KERN_WARNING "Session key encryption key is [%d] bytes; "
+ "minimum keysize for selected cipher is [%d] bytes.\n",
+ password_s_ptr->session_key_encryption_key_bytes,
+ crypto_tfm_alg_min_keysize(tfm));
+ rc = -EINVAL;
+ goto out;
+ }
+ if (tfm_mutex)
+ mutex_lock(tfm_mutex);
+ crypto_cipher_setkey(tfm, password_s_ptr->session_key_encryption_key,
+ crypt_stat->key_size);
+ /* TODO: virt_to_scatterlist */
+ encrypted_session_key = (char *)__get_free_page(GFP_KERNEL);
+ if (!encrypted_session_key) {
+ ecryptfs_printk(KERN_ERR, "Out of memory\n");
+ rc = -ENOMEM;
+ goto out_free_tfm;
+ }
+ session_key = (char *)__get_free_page(GFP_KERNEL);
+ if (!session_key) {
+ kfree(encrypted_session_key);
+ ecryptfs_printk(KERN_ERR, "Out of memory\n");
+ rc = -ENOMEM;
+ goto out_free_tfm;
+ }
+ memcpy(encrypted_session_key, auth_tok->session_key.encrypted_key,
+ auth_tok->session_key.encrypted_key_size);
+ src_sg[0].page = virt_to_page(encrypted_session_key);
+ src_sg[0].offset = 0;
+ BUG_ON(auth_tok->session_key.encrypted_key_size > PAGE_CACHE_SIZE);
+ src_sg[0].length = auth_tok->session_key.encrypted_key_size;
+ dst_sg[0].page = virt_to_page(session_key);
+ dst_sg[0].offset = 0;
+ auth_tok->session_key.decrypted_key_size =
+ auth_tok->session_key.encrypted_key_size;
+ dst_sg[0].length = auth_tok->session_key.encrypted_key_size;
+ /* TODO: Handle error condition */
+ crypto_cipher_decrypt(tfm, dst_sg, src_sg,
+ auth_tok->session_key.encrypted_key_size);
+ auth_tok->session_key.decrypted_key_size =
+ auth_tok->session_key.encrypted_key_size;
+ memcpy(auth_tok->session_key.decrypted_key, session_key,
+ auth_tok->session_key.decrypted_key_size);
+ auth_tok->session_key.flags |= ECRYPTFS_CONTAINS_DECRYPTED_KEY;
+ memcpy(crypt_stat->key, auth_tok->session_key.decrypted_key,
+ auth_tok->session_key.decrypted_key_size);
+ ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_KEY_VALID);
+ ecryptfs_printk(KERN_DEBUG, "Decrypted session key:\n");
+ if (ecryptfs_verbosity > 0)
+ ecryptfs_dump_hex(crypt_stat->key,
+ crypt_stat->key_size);
+ memset(encrypted_session_key, 0, PAGE_CACHE_SIZE);
+ free_page((unsigned long)encrypted_session_key);
+ memset(session_key, 0, PAGE_CACHE_SIZE);
+ free_page((unsigned long)session_key);
+out_free_tfm:
+ if (tfm_mutex)
+ mutex_unlock(tfm_mutex);
+ else
+ crypto_free_tfm(tfm);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_parse_packet_set
+ * @dest: The header page in memory
+ * @version: Version of file format, to guide parsing behavior
+ *
+ * Get crypt_stat to have the file's session key if the requisite key
+ * is available to decrypt the session key.
+ *
+ * Returns Zero if a valid authentication token was retrieved and
+ * processed; negative value for file not encrypted or for error
+ * conditions.
+ */
+int ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat,
+ unsigned char *src,
+ struct dentry *ecryptfs_dentry)
+{
+ size_t i = 0;
+ int rc = 0;
+ size_t found_auth_tok = 0;
+ size_t next_packet_is_auth_tok_packet;
+ char sig[ECRYPTFS_SIG_SIZE_HEX];
+ struct list_head auth_tok_list;
+ struct list_head *walker;
+ struct ecryptfs_auth_tok *chosen_auth_tok = NULL;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
+ &ecryptfs_superblock_to_private(
+ ecryptfs_dentry->d_sb)->mount_crypt_stat;
+ struct ecryptfs_auth_tok *candidate_auth_tok = NULL;
+ size_t packet_size;
+ struct ecryptfs_auth_tok *new_auth_tok;
+ unsigned char sig_tmp_space[ECRYPTFS_SIG_SIZE];
+ size_t tag_11_contents_size;
+ size_t tag_11_packet_size;
+
+ INIT_LIST_HEAD(&auth_tok_list);
+ /* Parse the header to find as many packets as we can, these will be
+ * added the our &auth_tok_list */
+ next_packet_is_auth_tok_packet = 1;
+ while (next_packet_is_auth_tok_packet) {
+ size_t max_packet_size = ((PAGE_CACHE_SIZE - 8) - i);
+
+ switch (src[i]) {
+ case ECRYPTFS_TAG_3_PACKET_TYPE:
+ rc = parse_tag_3_packet(crypt_stat,
+ (unsigned char *)&src[i],
+ &auth_tok_list, &new_auth_tok,
+ &packet_size, max_packet_size);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error parsing "
+ "tag 3 packet\n");
+ rc = -EIO;
+ goto out_wipe_list;
+ }
+ i += packet_size;
+ rc = parse_tag_11_packet((unsigned char *)&src[i],
+ sig_tmp_space,
+ ECRYPTFS_SIG_SIZE,
+ &tag_11_contents_size,
+ &tag_11_packet_size,
+ max_packet_size);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "No valid "
+ "(ecryptfs-specific) literal "
+ "packet containing "
+ "authentication token "
+ "signature found after "
+ "tag 3 packet\n");
+ rc = -EIO;
+ goto out_wipe_list;
+ }
+ i += tag_11_packet_size;
+ if (ECRYPTFS_SIG_SIZE != tag_11_contents_size) {
+ ecryptfs_printk(KERN_ERR, "Expected "
+ "signature of size [%d]; "
+ "read size [%d]\n",
+ ECRYPTFS_SIG_SIZE,
+ tag_11_contents_size);
+ rc = -EIO;
+ goto out_wipe_list;
+ }
+ ecryptfs_to_hex(new_auth_tok->token.password.signature,
+ sig_tmp_space, tag_11_contents_size);
+ new_auth_tok->token.password.signature[
+ ECRYPTFS_PASSWORD_SIG_SIZE] = '\0';
+ ECRYPTFS_SET_FLAG(crypt_stat->flags,
+ ECRYPTFS_ENCRYPTED);
+ break;
+ case ECRYPTFS_TAG_11_PACKET_TYPE:
+ ecryptfs_printk(KERN_WARNING, "Invalid packet set "
+ "(Tag 11 not allowed by itself)\n");
+ rc = -EIO;
+ goto out_wipe_list;
+ break;
+ default:
+ ecryptfs_printk(KERN_DEBUG, "No packet at offset "
+ "[%d] of the file header; hex value of "
+ "character is [0x%.2x]\n", i, src[i]);
+ next_packet_is_auth_tok_packet = 0;
+ }
+ }
+ if (list_empty(&auth_tok_list)) {
+ rc = -EINVAL; /* Do not support non-encrypted files in
+ * the 0.1 release */
+ goto out;
+ }
+ /* If we have a global auth tok, then we should try to use
+ * it */
+ if (mount_crypt_stat->global_auth_tok) {
+ memcpy(sig, mount_crypt_stat->global_auth_tok_sig,
+ ECRYPTFS_SIG_SIZE_HEX);
+ chosen_auth_tok = mount_crypt_stat->global_auth_tok;
+ } else
+ BUG(); /* We should always have a global auth tok in
+ * the 0.1 release */
+ /* Scan list to see if our chosen_auth_tok works */
+ list_for_each(walker, &auth_tok_list) {
+ struct ecryptfs_auth_tok_list_item *auth_tok_list_item;
+ auth_tok_list_item =
+ list_entry(walker, struct ecryptfs_auth_tok_list_item,
+ list);
+ candidate_auth_tok = &auth_tok_list_item->auth_tok;
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG,
+ "Considering cadidate auth tok:\n");
+ ecryptfs_dump_auth_tok(candidate_auth_tok);
+ }
+ /* TODO: Replace ECRYPTFS_SIG_SIZE_HEX w/ dynamic value */
+ if (candidate_auth_tok->token_type == ECRYPTFS_PASSWORD
+ && !strncmp(candidate_auth_tok->token.password.signature,
+ sig, ECRYPTFS_SIG_SIZE_HEX)) {
+ found_auth_tok = 1;
+ goto leave_list;
+ /* TODO: Transfer the common salt into the
+ * crypt_stat salt */
+ }
+ }
+leave_list:
+ if (!found_auth_tok) {
+ ecryptfs_printk(KERN_ERR, "Could not find authentication "
+ "token on temporary list for sig [%.*s]\n",
+ ECRYPTFS_SIG_SIZE_HEX, sig);
+ rc = -EIO;
+ goto out_wipe_list;
+ } else {
+ memcpy(&(candidate_auth_tok->token.password),
+ &(chosen_auth_tok->token.password),
+ sizeof(struct ecryptfs_password));
+ rc = decrypt_session_key(candidate_auth_tok, crypt_stat);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error decrypting the "
+ "session key\n");
+ goto out_wipe_list;
+ }
+ rc = ecryptfs_compute_root_iv(crypt_stat);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error computing "
+ "the root IV\n");
+ goto out_wipe_list;
+ }
+ }
+ rc = ecryptfs_init_crypt_ctx(crypt_stat);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error initializing crypto "
+ "context for cipher [%s]; rc = [%d]\n",
+ crypt_stat->cipher, rc);
+ }
+out_wipe_list:
+ wipe_auth_tok_list(&auth_tok_list);
+out:
+ return rc;
+}
+
+/**
+ * write_tag_11_packet
+ * @dest: Target into which Tag 11 packet is to be written
+ * @max: Maximum packet length
+ * @contents: Byte array of contents to copy in
+ * @contents_length: Number of bytes in contents
+ * @packet_length: Length of the Tag 11 packet written; zero on error
+ *
+ * Returns zero on success; non-zero on error.
+ */
+static int
+write_tag_11_packet(char *dest, int max, char *contents, size_t contents_length,
+ size_t *packet_length)
+{
+ int rc = 0;
+ size_t packet_size_length;
+
+ (*packet_length) = 0;
+ if ((13 + contents_length) > max) {
+ rc = -EINVAL;
+ ecryptfs_printk(KERN_ERR, "Packet length larger than "
+ "maximum allowable\n");
+ goto out;
+ }
+ /* General packet header */
+ /* Packet tag */
+ dest[(*packet_length)++] = ECRYPTFS_TAG_11_PACKET_TYPE;
+ /* Packet length */
+ rc = write_packet_length(&dest[(*packet_length)],
+ (13 + contents_length), &packet_size_length);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error generating tag 11 packet "
+ "header; cannot generate packet length\n");
+ goto out;
+ }
+ (*packet_length) += packet_size_length;
+ /* Tag 11 specific */
+ /* One-octet field that describes how the data is formatted */
+ dest[(*packet_length)++] = 0x62; /* binary data */
+ /* One-octet filename length followed by filename */
+ dest[(*packet_length)++] = 8;
+ memcpy(&dest[(*packet_length)], "_CONSOLE", 8);
+ (*packet_length) += 8;
+ /* Four-octet number indicating modification date */
+ memset(&dest[(*packet_length)], 0x00, 4);
+ (*packet_length) += 4;
+ /* Remainder is literal data */
+ memcpy(&dest[(*packet_length)], contents, contents_length);
+ (*packet_length) += contents_length;
+ out:
+ if (rc)
+ (*packet_length) = 0;
+ return rc;
+}
+
+/**
+ * write_tag_3_packet
+ * @dest: Buffer into which to write the packet
+ * @max: Maximum number of bytes that can be written
+ * @auth_tok: Authentication token
+ * @crypt_stat: The cryptographic context
+ * @key_rec: encrypted key
+ * @packet_size: This function will write the number of bytes that end
+ * up constituting the packet; set to zero on error
+ *
+ * Returns zero on success; non-zero on error.
+ */
+static int
+write_tag_3_packet(char *dest, size_t max, struct ecryptfs_auth_tok *auth_tok,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct ecryptfs_key_record *key_rec, size_t *packet_size)
+{
+ int rc = 0;
+
+ size_t i;
+ size_t signature_is_valid = 0;
+ size_t encrypted_session_key_valid = 0;
+ char session_key_encryption_key[ECRYPTFS_MAX_KEY_BYTES];
+ struct scatterlist dest_sg[2];
+ struct scatterlist src_sg[2];
+ struct crypto_tfm *tfm = NULL;
+ struct mutex *tfm_mutex = NULL;
+ size_t key_rec_size;
+ size_t packet_size_length;
+ size_t cipher_code;
+
+ (*packet_size) = 0;
+ /* Check for a valid signature on the auth_tok */
+ for (i = 0; i < ECRYPTFS_SIG_SIZE_HEX; i++)
+ signature_is_valid |= auth_tok->token.password.signature[i];
+ if (!signature_is_valid)
+ BUG();
+ ecryptfs_from_hex((*key_rec).sig, auth_tok->token.password.signature,
+ ECRYPTFS_SIG_SIZE);
+ encrypted_session_key_valid = 0;
+ for (i = 0; i < crypt_stat->key_size; i++)
+ encrypted_session_key_valid |=
+ auth_tok->session_key.encrypted_key[i];
+ if (encrypted_session_key_valid) {
+ memcpy((*key_rec).enc_key,
+ auth_tok->session_key.encrypted_key,
+ auth_tok->session_key.encrypted_key_size);
+ goto encrypted_session_key_set;
+ }
+ if (auth_tok->session_key.encrypted_key_size == 0)
+ auth_tok->session_key.encrypted_key_size =
+ crypt_stat->key_size;
+ if (crypt_stat->key_size == 24
+ && strcmp("aes", crypt_stat->cipher) == 0) {
+ memset((crypt_stat->key + 24), 0, 8);
+ auth_tok->session_key.encrypted_key_size = 32;
+ }
+ (*key_rec).enc_key_size =
+ auth_tok->session_key.encrypted_key_size;
+ if (ECRYPTFS_CHECK_FLAG(auth_tok->token.password.flags,
+ ECRYPTFS_SESSION_KEY_ENCRYPTION_KEY_SET)) {
+ ecryptfs_printk(KERN_DEBUG, "Using previously generated "
+ "session key encryption key of size [%d]\n",
+ auth_tok->token.password.
+ session_key_encryption_key_bytes);
+ memcpy(session_key_encryption_key,
+ auth_tok->token.password.session_key_encryption_key,
+ crypt_stat->key_size);
+ ecryptfs_printk(KERN_DEBUG,
+ "Cached session key " "encryption key: \n");
+ if (ecryptfs_verbosity > 0)
+ ecryptfs_dump_hex(session_key_encryption_key, 16);
+ }
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "Session key encryption key:\n");
+ ecryptfs_dump_hex(session_key_encryption_key, 16);
+ }
+ rc = virt_to_scatterlist(crypt_stat->key,
+ (*key_rec).enc_key_size, src_sg, 2);
+ if (!rc) {
+ ecryptfs_printk(KERN_ERR, "Error generating scatterlist "
+ "for crypt_stat session key\n");
+ rc = -ENOMEM;
+ goto out;
+ }
+ rc = virt_to_scatterlist((*key_rec).enc_key,
+ (*key_rec).enc_key_size, dest_sg, 2);
+ if (!rc) {
+ ecryptfs_printk(KERN_ERR, "Error generating scatterlist "
+ "for crypt_stat encrypted session key\n");
+ rc = -ENOMEM;
+ goto out;
+ }
+ if (!strcmp(crypt_stat->cipher,
+ crypt_stat->mount_crypt_stat->global_default_cipher_name)
+ && crypt_stat->mount_crypt_stat->global_key_tfm) {
+ tfm = crypt_stat->mount_crypt_stat->global_key_tfm;
+ tfm_mutex = &crypt_stat->mount_crypt_stat->global_key_tfm_mutex;
+ } else
+ tfm = crypto_alloc_tfm(crypt_stat->cipher, 0);
+ if (!tfm) {
+ ecryptfs_printk(KERN_ERR, "Could not initialize crypto "
+ "context for cipher [%s]\n",
+ crypt_stat->cipher);
+ rc = -EINVAL;
+ goto out;
+ }
+ if (tfm_mutex)
+ mutex_lock(tfm_mutex);
+ rc = crypto_cipher_setkey(tfm, session_key_encryption_key,
+ crypt_stat->key_size);
+ if (rc < 0) {
+ if (tfm_mutex)
+ mutex_unlock(tfm_mutex);
+ ecryptfs_printk(KERN_ERR, "Error setting key for crypto "
+ "context\n");
+ goto out;
+ }
+ rc = 0;
+ ecryptfs_printk(KERN_DEBUG, "Encrypting [%d] bytes of the key\n",
+ crypt_stat->key_size);
+ crypto_cipher_encrypt(tfm, dest_sg, src_sg,
+ (*key_rec).enc_key_size);
+ if (tfm_mutex)
+ mutex_unlock(tfm_mutex);
+ ecryptfs_printk(KERN_DEBUG, "This should be the encrypted key:\n");
+ if (ecryptfs_verbosity > 0)
+ ecryptfs_dump_hex((*key_rec).enc_key,
+ (*key_rec).enc_key_size);
+encrypted_session_key_set:
+ /* Now we have a valid key_rec. Append it to the
+ * key_rec set. */
+ key_rec_size = (sizeof(struct ecryptfs_key_record)
+ - ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES
+ + ((*key_rec).enc_key_size));
+ /* TODO: Include a packet size limit as a parameter to this
+ * function once we have multi-packet headers (for versions
+ * later than 0.1 */
+ if (key_rec_size >= ECRYPTFS_MAX_KEYSET_SIZE) {
+ ecryptfs_printk(KERN_ERR, "Keyset too large\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ /* TODO: Packet size limit */
+ /* We have 5 bytes of surrounding packet data */
+ if ((0x05 + ECRYPTFS_SALT_SIZE
+ + (*key_rec).enc_key_size) >= max) {
+ ecryptfs_printk(KERN_ERR, "Authentication token is too "
+ "large\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ /* This format is inspired by OpenPGP; see RFC 2440
+ * packet tag 3 */
+ dest[(*packet_size)++] = ECRYPTFS_TAG_3_PACKET_TYPE;
+ /* ver+cipher+s2k+hash+salt+iter+enc_key */
+ rc = write_packet_length(&dest[(*packet_size)],
+ (0x05 + ECRYPTFS_SALT_SIZE
+ + (*key_rec).enc_key_size),
+ &packet_size_length);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error generating tag 3 packet "
+ "header; cannot generate packet length\n");
+ goto out;
+ }
+ (*packet_size) += packet_size_length;
+ dest[(*packet_size)++] = 0x04; /* version 4 */
+ cipher_code = ecryptfs_code_for_cipher_string(crypt_stat);
+ if (cipher_code == 0) {
+ ecryptfs_printk(KERN_WARNING, "Unable to generate code for "
+ "cipher [%s]\n", crypt_stat->cipher);
+ rc = -EINVAL;
+ goto out;
+ }
+ dest[(*packet_size)++] = cipher_code;
+ dest[(*packet_size)++] = 0x03; /* S2K */
+ dest[(*packet_size)++] = 0x01; /* MD5 (TODO: parameterize) */
+ memcpy(&dest[(*packet_size)], auth_tok->token.password.salt,
+ ECRYPTFS_SALT_SIZE);
+ (*packet_size) += ECRYPTFS_SALT_SIZE; /* salt */
+ dest[(*packet_size)++] = 0x60; /* hash iterations (65536) */
+ memcpy(&dest[(*packet_size)], (*key_rec).enc_key,
+ (*key_rec).enc_key_size);
+ (*packet_size) += (*key_rec).enc_key_size;
+out:
+ if (tfm && !tfm_mutex)
+ crypto_free_tfm(tfm);
+ if (rc)
+ (*packet_size) = 0;
+ return rc;
+}
+
+/**
+ * ecryptfs_generate_key_packet_set
+ * @dest: Virtual address from which to write the key record set
+ * @crypt_stat: The cryptographic context from which the
+ * authentication tokens will be retrieved
+ * @ecryptfs_dentry: The dentry, used to retrieve the mount crypt stat
+ * for the global parameters
+ * @len: The amount written
+ * @max: The maximum amount of data allowed to be written
+ *
+ * Generates a key packet set and writes it to the virtual address
+ * passed in.
+ *
+ * Returns zero on success; non-zero on error.
+ */
+int
+ecryptfs_generate_key_packet_set(char *dest_base,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct dentry *ecryptfs_dentry, size_t *len,
+ size_t max)
+{
+ int rc = 0;
+ struct ecryptfs_auth_tok *auth_tok;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
+ &ecryptfs_superblock_to_private(
+ ecryptfs_dentry->d_sb)->mount_crypt_stat;
+ size_t written;
+ struct ecryptfs_key_record key_rec;
+
+ (*len) = 0;
+ if (mount_crypt_stat->global_auth_tok) {
+ auth_tok = mount_crypt_stat->global_auth_tok;
+ if (auth_tok->token_type == ECRYPTFS_PASSWORD) {
+ rc = write_tag_3_packet((dest_base + (*len)),
+ max, auth_tok,
+ crypt_stat, &key_rec,
+ &written);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error "
+ "writing tag 3 packet\n");
+ goto out;
+ }
+ (*len) += written;
+ /* Write auth tok signature packet */
+ rc = write_tag_11_packet(
+ (dest_base + (*len)),
+ (max - (*len)),
+ key_rec.sig, ECRYPTFS_SIG_SIZE, &written);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error writing "
+ "auth tok signature packet\n");
+ goto out;
+ }
+ (*len) += written;
+ } else {
+ ecryptfs_printk(KERN_WARNING, "Unsupported "
+ "authentication token type\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error writing "
+ "authentication token packet with sig "
+ "= [%s]\n",
+ mount_crypt_stat->global_auth_tok_sig);
+ rc = -EIO;
+ goto out;
+ }
+ } else
+ BUG();
+ if (likely((max - (*len)) > 0)) {
+ dest_base[(*len)] = 0x00;
+ } else {
+ ecryptfs_printk(KERN_ERR, "Error writing boundary byte\n");
+ rc = -EIO;
+ }
+out:
+ if (rc)
+ (*len) = 0;
+ return rc;
+}
--- /dev/null
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 1997-2003 Erez Zadok
+ * Copyright (C) 2001-2003 Stony Brook University
+ * Copyright (C) 2004-2006 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ * Michael C. Thompson <mcthomps@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <linux/dcache.h>
+#include <linux/file.h>
+#include <linux/module.h>
+#include <linux/namei.h>
+#include <linux/skbuff.h>
+#include <linux/crypto.h>
+#include <linux/netlink.h>
+#include <linux/mount.h>
+#include <linux/dcache.h>
+#include <linux/pagemap.h>
+#include <linux/key.h>
+#include <linux/parser.h>
+#include "ecryptfs_kernel.h"
+
+/**
+ * Module parameter that defines the ecryptfs_verbosity level.
+ */
+int ecryptfs_verbosity = 0;
+
+module_param(ecryptfs_verbosity, int, 0);
+MODULE_PARM_DESC(ecryptfs_verbosity,
+ "Initial verbosity level (0 or 1; defaults to "
+ "0, which is Quiet)");
+
+void __ecryptfs_printk(const char *fmt, ...)
+{
+ va_list args;
+ va_start(args, fmt);
+ if (fmt[1] == '7') { /* KERN_DEBUG */
+ if (ecryptfs_verbosity >= 1)
+ vprintk(fmt, args);
+ } else
+ vprintk(fmt, args);
+ va_end(args);
+}
+
+/**
+ * ecryptfs_interpose
+ * @lower_dentry: Existing dentry in the lower filesystem
+ * @dentry: ecryptfs' dentry
+ * @sb: ecryptfs's super_block
+ * @flag: If set to true, then d_add is called, else d_instantiate is called
+ *
+ * Interposes upper and lower dentries.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+int ecryptfs_interpose(struct dentry *lower_dentry, struct dentry *dentry,
+ struct super_block *sb, int flag)
+{
+ struct inode *lower_inode;
+ struct inode *inode;
+ int rc = 0;
+
+ lower_inode = lower_dentry->d_inode;
+ if (lower_inode->i_sb != ecryptfs_superblock_to_lower(sb)) {
+ rc = -EXDEV;
+ goto out;
+ }
+ if (!igrab(lower_inode)) {
+ rc = -ESTALE;
+ goto out;
+ }
+ inode = iget5_locked(sb, (unsigned long)lower_inode,
+ ecryptfs_inode_test, ecryptfs_inode_set,
+ lower_inode);
+ if (!inode) {
+ rc = -EACCES;
+ iput(lower_inode);
+ goto out;
+ }
+ if (inode->i_state & I_NEW)
+ unlock_new_inode(inode);
+ else
+ iput(lower_inode);
+ if (S_ISLNK(lower_inode->i_mode))
+ inode->i_op = &ecryptfs_symlink_iops;
+ else if (S_ISDIR(lower_inode->i_mode))
+ inode->i_op = &ecryptfs_dir_iops;
+ if (S_ISDIR(lower_inode->i_mode))
+ inode->i_fop = &ecryptfs_dir_fops;
+ /* TODO: Is there a better way to identify if the inode is
+ * special? */
+ if (S_ISBLK(lower_inode->i_mode) || S_ISCHR(lower_inode->i_mode) ||
+ S_ISFIFO(lower_inode->i_mode) || S_ISSOCK(lower_inode->i_mode))
+ init_special_inode(inode, lower_inode->i_mode,
+ lower_inode->i_rdev);
+ dentry->d_op = &ecryptfs_dops;
+ if (flag)
+ d_add(dentry, inode);
+ else
+ d_instantiate(dentry, inode);
+ ecryptfs_copy_attr_all(inode, lower_inode);
+ /* This size will be overwritten for real files w/ headers and
+ * other metadata */
+ ecryptfs_copy_inode_size(inode, lower_inode);
+out:
+ return rc;
+}
+
+enum { ecryptfs_opt_sig, ecryptfs_opt_ecryptfs_sig, ecryptfs_opt_debug,
+ ecryptfs_opt_ecryptfs_debug, ecryptfs_opt_cipher,
+ ecryptfs_opt_ecryptfs_cipher, ecryptfs_opt_ecryptfs_key_bytes,
+ ecryptfs_opt_passthrough, ecryptfs_opt_err };
+
+static match_table_t tokens = {
+ {ecryptfs_opt_sig, "sig=%s"},
+ {ecryptfs_opt_ecryptfs_sig, "ecryptfs_sig=%s"},
+ {ecryptfs_opt_debug, "debug=%u"},
+ {ecryptfs_opt_ecryptfs_debug, "ecryptfs_debug=%u"},
+ {ecryptfs_opt_cipher, "cipher=%s"},
+ {ecryptfs_opt_ecryptfs_cipher, "ecryptfs_cipher=%s"},
+ {ecryptfs_opt_ecryptfs_key_bytes, "ecryptfs_key_bytes=%u"},
+ {ecryptfs_opt_passthrough, "ecryptfs_passthrough"},
+ {ecryptfs_opt_err, NULL}
+};
+
+/**
+ * ecryptfs_verify_version
+ * @version: The version number to confirm
+ *
+ * Returns zero on good version; non-zero otherwise
+ */
+static int ecryptfs_verify_version(u16 version)
+{
+ int rc = 0;
+ unsigned char major;
+ unsigned char minor;
+
+ major = ((version >> 8) & 0xFF);
+ minor = (version & 0xFF);
+ if (major != ECRYPTFS_VERSION_MAJOR) {
+ ecryptfs_printk(KERN_ERR, "Major version number mismatch. "
+ "Expected [%d]; got [%d]\n",
+ ECRYPTFS_VERSION_MAJOR, major);
+ rc = -EINVAL;
+ goto out;
+ }
+ if (minor != ECRYPTFS_VERSION_MINOR) {
+ ecryptfs_printk(KERN_ERR, "Minor version number mismatch. "
+ "Expected [%d]; got [%d]\n",
+ ECRYPTFS_VERSION_MINOR, minor);
+ rc = -EINVAL;
+ goto out;
+ }
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_parse_options
+ * @sb: The ecryptfs super block
+ * @options: The options pased to the kernel
+ *
+ * Parse mount options:
+ * debug=N - ecryptfs_verbosity level for debug output
+ * sig=XXX - description(signature) of the key to use
+ *
+ * Returns the dentry object of the lower-level (lower/interposed)
+ * directory; We want to mount our stackable file system on top of
+ * that lower directory.
+ *
+ * The signature of the key to use must be the description of a key
+ * already in the keyring. Mounting will fail if the key can not be
+ * found.
+ *
+ * Returns zero on success; non-zero on error
+ */
+static int ecryptfs_parse_options(struct super_block *sb, char *options)
+{
+ char *p;
+ int rc = 0;
+ int sig_set = 0;
+ int cipher_name_set = 0;
+ int cipher_key_bytes;
+ int cipher_key_bytes_set = 0;
+ struct key *auth_tok_key = NULL;
+ struct ecryptfs_auth_tok *auth_tok = NULL;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
+ &ecryptfs_superblock_to_private(sb)->mount_crypt_stat;
+ substring_t args[MAX_OPT_ARGS];
+ int token;
+ char *sig_src;
+ char *sig_dst;
+ char *debug_src;
+ char *cipher_name_dst;
+ char *cipher_name_src;
+ char *cipher_key_bytes_src;
+ struct crypto_tfm *tmp_tfm;
+ int cipher_name_len;
+
+ if (!options) {
+ rc = -EINVAL;
+ goto out;
+ }
+ while ((p = strsep(&options, ",")) != NULL) {
+ if (!*p)
+ continue;
+ token = match_token(p, tokens, args);
+ switch (token) {
+ case ecryptfs_opt_sig:
+ case ecryptfs_opt_ecryptfs_sig:
+ sig_src = args[0].from;
+ sig_dst =
+ mount_crypt_stat->global_auth_tok_sig;
+ memcpy(sig_dst, sig_src, ECRYPTFS_SIG_SIZE_HEX);
+ sig_dst[ECRYPTFS_SIG_SIZE_HEX] = '\0';
+ ecryptfs_printk(KERN_DEBUG,
+ "The mount_crypt_stat "
+ "global_auth_tok_sig set to: "
+ "[%s]\n", sig_dst);
+ sig_set = 1;
+ break;
+ case ecryptfs_opt_debug:
+ case ecryptfs_opt_ecryptfs_debug:
+ debug_src = args[0].from;
+ ecryptfs_verbosity =
+ (int)simple_strtol(debug_src, &debug_src,
+ 0);
+ ecryptfs_printk(KERN_DEBUG,
+ "Verbosity set to [%d]" "\n",
+ ecryptfs_verbosity);
+ break;
+ case ecryptfs_opt_cipher:
+ case ecryptfs_opt_ecryptfs_cipher:
+ cipher_name_src = args[0].from;
+ cipher_name_dst =
+ mount_crypt_stat->
+ global_default_cipher_name;
+ strncpy(cipher_name_dst, cipher_name_src,
+ ECRYPTFS_MAX_CIPHER_NAME_SIZE);
+ ecryptfs_printk(KERN_DEBUG,
+ "The mount_crypt_stat "
+ "global_default_cipher_name set to: "
+ "[%s]\n", cipher_name_dst);
+ cipher_name_set = 1;
+ break;
+ case ecryptfs_opt_ecryptfs_key_bytes:
+ cipher_key_bytes_src = args[0].from;
+ cipher_key_bytes =
+ (int)simple_strtol(cipher_key_bytes_src,
+ &cipher_key_bytes_src, 0);
+ mount_crypt_stat->global_default_cipher_key_size =
+ cipher_key_bytes;
+ ecryptfs_printk(KERN_DEBUG,
+ "The mount_crypt_stat "
+ "global_default_cipher_key_size "
+ "set to: [%d]\n", mount_crypt_stat->
+ global_default_cipher_key_size);
+ cipher_key_bytes_set = 1;
+ break;
+ case ecryptfs_opt_passthrough:
+ mount_crypt_stat->flags |=
+ ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED;
+ break;
+ case ecryptfs_opt_err:
+ default:
+ ecryptfs_printk(KERN_WARNING,
+ "eCryptfs: unrecognized option '%s'\n",
+ p);
+ }
+ }
+ /* Do not support lack of mount-wide signature in 0.1
+ * release */
+ if (!sig_set) {
+ rc = -EINVAL;
+ ecryptfs_printk(KERN_ERR, "You must supply a valid "
+ "passphrase auth tok signature as a mount "
+ "parameter; see the eCryptfs README\n");
+ goto out;
+ }
+ if (!cipher_name_set) {
+ cipher_name_len = strlen(ECRYPTFS_DEFAULT_CIPHER);
+ if (unlikely(cipher_name_len
+ >= ECRYPTFS_MAX_CIPHER_NAME_SIZE)) {
+ rc = -EINVAL;
+ BUG();
+ goto out;
+ }
+ memcpy(mount_crypt_stat->global_default_cipher_name,
+ ECRYPTFS_DEFAULT_CIPHER, cipher_name_len);
+ mount_crypt_stat->global_default_cipher_name[cipher_name_len]
+ = '\0';
+ }
+ if (!cipher_key_bytes_set) {
+ mount_crypt_stat->global_default_cipher_key_size =
+ ECRYPTFS_DEFAULT_KEY_BYTES;
+ ecryptfs_printk(KERN_DEBUG, "Cipher key size was not "
+ "specified. Defaulting to [%d]\n",
+ mount_crypt_stat->
+ global_default_cipher_key_size);
+ }
+ rc = ecryptfs_process_cipher(
+ &tmp_tfm,
+ &mount_crypt_stat->global_key_tfm,
+ mount_crypt_stat->global_default_cipher_name,
+ mount_crypt_stat->global_default_cipher_key_size);
+ if (tmp_tfm)
+ crypto_free_tfm(tmp_tfm);
+ if (rc) {
+ printk(KERN_ERR "Error attempting to initialize cipher [%s] "
+ "with key size [%Zd] bytes; rc = [%d]\n",
+ mount_crypt_stat->global_default_cipher_name,
+ mount_crypt_stat->global_default_cipher_key_size, rc);
+ rc = -EINVAL;
+ goto out;
+ }
+ mutex_init(&mount_crypt_stat->global_key_tfm_mutex);
+ ecryptfs_printk(KERN_DEBUG, "Requesting the key with description: "
+ "[%s]\n", mount_crypt_stat->global_auth_tok_sig);
+ /* The reference to this key is held until umount is done The
+ * call to key_put is done in ecryptfs_put_super() */
+ auth_tok_key = request_key(&key_type_user,
+ mount_crypt_stat->global_auth_tok_sig,
+ NULL);
+ if (!auth_tok_key || IS_ERR(auth_tok_key)) {
+ ecryptfs_printk(KERN_ERR, "Could not find key with "
+ "description: [%s]\n",
+ mount_crypt_stat->global_auth_tok_sig);
+ process_request_key_err(PTR_ERR(auth_tok_key));
+ rc = -EINVAL;
+ goto out;
+ }
+ auth_tok = ecryptfs_get_key_payload_data(auth_tok_key);
+ if (ecryptfs_verify_version(auth_tok->version)) {
+ ecryptfs_printk(KERN_ERR, "Data structure version mismatch. "
+ "Userspace tools must match eCryptfs kernel "
+ "module with major version [%d] and minor "
+ "version [%d]\n", ECRYPTFS_VERSION_MAJOR,
+ ECRYPTFS_VERSION_MINOR);
+ rc = -EINVAL;
+ goto out;
+ }
+ if (auth_tok->token_type != ECRYPTFS_PASSWORD) {
+ ecryptfs_printk(KERN_ERR, "Invalid auth_tok structure "
+ "returned from key\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ mount_crypt_stat->global_auth_tok_key = auth_tok_key;
+ mount_crypt_stat->global_auth_tok = auth_tok;
+out:
+ return rc;
+}
+
+struct kmem_cache *ecryptfs_sb_info_cache;
+
+/**
+ * ecryptfs_fill_super
+ * @sb: The ecryptfs super block
+ * @raw_data: The options passed to mount
+ * @silent: Not used but required by function prototype
+ *
+ * Sets up what we can of the sb, rest is done in ecryptfs_read_super
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int
+ecryptfs_fill_super(struct super_block *sb, void *raw_data, int silent)
+{
+ int rc = 0;
+
+ /* Released in ecryptfs_put_super() */
+ ecryptfs_set_superblock_private(sb,
+ kmem_cache_alloc(ecryptfs_sb_info_cache,
+ SLAB_KERNEL));
+ if (!ecryptfs_superblock_to_private(sb)) {
+ ecryptfs_printk(KERN_WARNING, "Out of memory\n");
+ rc = -ENOMEM;
+ goto out;
+ }
+ memset(ecryptfs_superblock_to_private(sb), 0,
+ sizeof(struct ecryptfs_sb_info));
+ sb->s_op = &ecryptfs_sops;
+ /* Released through deactivate_super(sb) from get_sb_nodev */
+ sb->s_root = d_alloc(NULL, &(const struct qstr) {
+ .hash = 0,.name = "/",.len = 1});
+ if (!sb->s_root) {
+ ecryptfs_printk(KERN_ERR, "d_alloc failed\n");
+ rc = -ENOMEM;
+ goto out;
+ }
+ sb->s_root->d_op = &ecryptfs_dops;
+ sb->s_root->d_sb = sb;
+ sb->s_root->d_parent = sb->s_root;
+ /* Released in d_release when dput(sb->s_root) is called */
+ /* through deactivate_super(sb) from get_sb_nodev() */
+ ecryptfs_set_dentry_private(sb->s_root,
+ kmem_cache_alloc(ecryptfs_dentry_info_cache,
+ SLAB_KERNEL));
+ if (!ecryptfs_dentry_to_private(sb->s_root)) {
+ ecryptfs_printk(KERN_ERR,
+ "dentry_info_cache alloc failed\n");
+ rc = -ENOMEM;
+ goto out;
+ }
+ memset(ecryptfs_dentry_to_private(sb->s_root), 0,
+ sizeof(struct ecryptfs_dentry_info));
+ rc = 0;
+out:
+ /* Should be able to rely on deactivate_super called from
+ * get_sb_nodev */
+ return rc;
+}
+
+/**
+ * ecryptfs_read_super
+ * @sb: The ecryptfs super block
+ * @dev_name: The path to mount over
+ *
+ * Read the super block of the lower filesystem, and use
+ * ecryptfs_interpose to create our initial inode and super block
+ * struct.
+ */
+static int ecryptfs_read_super(struct super_block *sb, const char *dev_name)
+{
+ int rc;
+ struct nameidata nd;
+ struct dentry *lower_root;
+ struct vfsmount *lower_mnt;
+
+ memset(&nd, 0, sizeof(struct nameidata));
+ rc = path_lookup(dev_name, LOOKUP_FOLLOW, &nd);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "path_lookup() failed\n");
+ goto out_free;
+ }
+ lower_root = nd.dentry;
+ if (!lower_root->d_inode) {
+ ecryptfs_printk(KERN_WARNING,
+ "No directory to interpose on\n");
+ rc = -ENOENT;
+ goto out_free;
+ }
+ lower_mnt = nd.mnt;
+ ecryptfs_set_superblock_lower(sb, lower_root->d_sb);
+ sb->s_maxbytes = lower_root->d_sb->s_maxbytes;
+ ecryptfs_set_dentry_lower(sb->s_root, lower_root);
+ ecryptfs_set_dentry_lower_mnt(sb->s_root, lower_mnt);
+ if ((rc = ecryptfs_interpose(lower_root, sb->s_root, sb, 0)))
+ goto out_free;
+ rc = 0;
+ goto out;
+out_free:
+ path_release(&nd);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_get_sb
+ * @fs_type
+ * @flags
+ * @dev_name: The path to mount over
+ * @raw_data: The options passed into the kernel
+ *
+ * The whole ecryptfs_get_sb process is broken into 4 functions:
+ * ecryptfs_parse_options(): handle options passed to ecryptfs, if any
+ * ecryptfs_fill_super(): used by get_sb_nodev, fills out the super_block
+ * with as much information as it can before needing
+ * the lower filesystem.
+ * ecryptfs_read_super(): this accesses the lower filesystem and uses
+ * ecryptfs_interpolate to perform most of the linking
+ * ecryptfs_interpolate(): links the lower filesystem into ecryptfs
+ */
+static int ecryptfs_get_sb(struct file_system_type *fs_type, int flags,
+ const char *dev_name, void *raw_data,
+ struct vfsmount *mnt)
+{
+ int rc;
+ struct super_block *sb;
+
+ rc = get_sb_nodev(fs_type, flags, raw_data, ecryptfs_fill_super, mnt);
+ if (rc < 0) {
+ printk(KERN_ERR "Getting sb failed; rc = [%d]\n", rc);
+ goto out;
+ }
+ sb = mnt->mnt_sb;
+ rc = ecryptfs_parse_options(sb, raw_data);
+ if (rc) {
+ printk(KERN_ERR "Error parsing options; rc = [%d]\n", rc);
+ goto out_abort;
+ }
+ rc = ecryptfs_read_super(sb, dev_name);
+ if (rc) {
+ printk(KERN_ERR "Reading sb failed; rc = [%d]\n", rc);
+ goto out_abort;
+ }
+ goto out;
+out_abort:
+ dput(sb->s_root);
+ up_write(&sb->s_umount);
+ deactivate_super(sb);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_kill_block_super
+ * @sb: The ecryptfs super block
+ *
+ * Used to bring the superblock down and free the private data.
+ * Private data is free'd in ecryptfs_put_super()
+ */
+static void ecryptfs_kill_block_super(struct super_block *sb)
+{
+ generic_shutdown_super(sb);
+}
+
+static struct file_system_type ecryptfs_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "ecryptfs",
+ .get_sb = ecryptfs_get_sb,
+ .kill_sb = ecryptfs_kill_block_super,
+ .fs_flags = 0
+};
+
+/**
+ * inode_info_init_once
+ *
+ * Initializes the ecryptfs_inode_info_cache when it is created
+ */
+static void
+inode_info_init_once(void *vptr, struct kmem_cache *cachep, unsigned long flags)
+{
+ struct ecryptfs_inode_info *ei = (struct ecryptfs_inode_info *)vptr;
+
+ if ((flags & (SLAB_CTOR_VERIFY | SLAB_CTOR_CONSTRUCTOR)) ==
+ SLAB_CTOR_CONSTRUCTOR)
+ inode_init_once(&ei->vfs_inode);
+}
+
+static struct ecryptfs_cache_info {
+ kmem_cache_t **cache;
+ const char *name;
+ size_t size;
+ void (*ctor)(void*, struct kmem_cache *, unsigned long);
+} ecryptfs_cache_infos[] = {
+ {
+ .cache = &ecryptfs_auth_tok_list_item_cache,
+ .name = "ecryptfs_auth_tok_list_item",
+ .size = sizeof(struct ecryptfs_auth_tok_list_item),
+ },
+ {
+ .cache = &ecryptfs_file_info_cache,
+ .name = "ecryptfs_file_cache",
+ .size = sizeof(struct ecryptfs_file_info),
+ },
+ {
+ .cache = &ecryptfs_dentry_info_cache,
+ .name = "ecryptfs_dentry_info_cache",
+ .size = sizeof(struct ecryptfs_dentry_info),
+ },
+ {
+ .cache = &ecryptfs_inode_info_cache,
+ .name = "ecryptfs_inode_cache",
+ .size = sizeof(struct ecryptfs_inode_info),
+ .ctor = inode_info_init_once,
+ },
+ {
+ .cache = &ecryptfs_sb_info_cache,
+ .name = "ecryptfs_sb_cache",
+ .size = sizeof(struct ecryptfs_sb_info),
+ },
+ {
+ .cache = &ecryptfs_header_cache_0,
+ .name = "ecryptfs_headers_0",
+ .size = PAGE_CACHE_SIZE,
+ },
+ {
+ .cache = &ecryptfs_header_cache_1,
+ .name = "ecryptfs_headers_1",
+ .size = PAGE_CACHE_SIZE,
+ },
+ {
+ .cache = &ecryptfs_header_cache_2,
+ .name = "ecryptfs_headers_2",
+ .size = PAGE_CACHE_SIZE,
+ },
+ {
+ .cache = &ecryptfs_lower_page_cache,
+ .name = "ecryptfs_lower_page_cache",
+ .size = PAGE_CACHE_SIZE,
+ },
+};
+
+static void ecryptfs_free_kmem_caches(void)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(ecryptfs_cache_infos); i++) {
+ struct ecryptfs_cache_info *info;
+
+ info = &ecryptfs_cache_infos[i];
+ if (*(info->cache))
+ kmem_cache_destroy(*(info->cache));
+ }
+}
+
+/**
+ * ecryptfs_init_kmem_caches
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int ecryptfs_init_kmem_caches(void)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(ecryptfs_cache_infos); i++) {
+ struct ecryptfs_cache_info *info;
+
+ info = &ecryptfs_cache_infos[i];
+ *(info->cache) = kmem_cache_create(info->name, info->size,
+ 0, SLAB_HWCACHE_ALIGN, info->ctor, NULL);
+ if (!*(info->cache)) {
+ ecryptfs_free_kmem_caches();
+ ecryptfs_printk(KERN_WARNING, "%s: "
+ "kmem_cache_create failed\n",
+ info->name);
+ return -ENOMEM;
+ }
+ }
+ return 0;
+}
+
+struct ecryptfs_obj {
+ char *name;
+ struct list_head slot_list;
+ struct kobject kobj;
+};
+
+struct ecryptfs_attribute {
+ struct attribute attr;
+ ssize_t(*show) (struct ecryptfs_obj *, char *);
+ ssize_t(*store) (struct ecryptfs_obj *, const char *, size_t);
+};
+
+static ssize_t
+ecryptfs_attr_store(struct kobject *kobj,
+ struct attribute *attr, const char *buf, size_t len)
+{
+ struct ecryptfs_obj *obj = container_of(kobj, struct ecryptfs_obj,
+ kobj);
+ struct ecryptfs_attribute *attribute =
+ container_of(attr, struct ecryptfs_attribute, attr);
+
+ return (attribute->store ? attribute->store(obj, buf, len) : 0);
+}
+
+static ssize_t
+ecryptfs_attr_show(struct kobject *kobj, struct attribute *attr, char *buf)
+{
+ struct ecryptfs_obj *obj = container_of(kobj, struct ecryptfs_obj,
+ kobj);
+ struct ecryptfs_attribute *attribute =
+ container_of(attr, struct ecryptfs_attribute, attr);
+
+ return (attribute->show ? attribute->show(obj, buf) : 0);
+}
+
+static struct sysfs_ops ecryptfs_sysfs_ops = {
+ .show = ecryptfs_attr_show,
+ .store = ecryptfs_attr_store
+};
+
+static struct kobj_type ecryptfs_ktype = {
+ .sysfs_ops = &ecryptfs_sysfs_ops
+};
+
+static decl_subsys(ecryptfs, &ecryptfs_ktype, NULL);
+
+static ssize_t version_show(struct ecryptfs_obj *obj, char *buff)
+{
+ return snprintf(buff, PAGE_SIZE, "%d\n", ECRYPTFS_VERSIONING_MASK);
+}
+
+static struct ecryptfs_attribute sysfs_attr_version = __ATTR_RO(version);
+
+struct ecryptfs_version_str_map_elem {
+ u32 flag;
+ char *str;
+} ecryptfs_version_str_map[] = {
+ {ECRYPTFS_VERSIONING_PASSPHRASE, "passphrase"},
+ {ECRYPTFS_VERSIONING_PUBKEY, "pubkey"},
+ {ECRYPTFS_VERSIONING_PLAINTEXT_PASSTHROUGH, "plaintext passthrough"},
+ {ECRYPTFS_VERSIONING_POLICY, "policy"}
+};
+
+static ssize_t version_str_show(struct ecryptfs_obj *obj, char *buff)
+{
+ int i;
+ int remaining = PAGE_SIZE;
+ int total_written = 0;
+
+ buff[0] = '\0';
+ for (i = 0; i < ARRAY_SIZE(ecryptfs_version_str_map); i++) {
+ int entry_size;
+
+ if (!(ECRYPTFS_VERSIONING_MASK
+ & ecryptfs_version_str_map[i].flag))
+ continue;
+ entry_size = strlen(ecryptfs_version_str_map[i].str);
+ if ((entry_size + 2) > remaining)
+ goto out;
+ memcpy(buff, ecryptfs_version_str_map[i].str, entry_size);
+ buff[entry_size++] = '\n';
+ buff[entry_size] = '\0';
+ buff += entry_size;
+ total_written += entry_size;
+ remaining -= entry_size;
+ }
+out:
+ return total_written;
+}
+
+static struct ecryptfs_attribute sysfs_attr_version_str = __ATTR_RO(version_str);
+
+static int do_sysfs_registration(void)
+{
+ int rc;
+
+ if ((rc = subsystem_register(&ecryptfs_subsys))) {
+ printk(KERN_ERR
+ "Unable to register ecryptfs sysfs subsystem\n");
+ goto out;
+ }
+ rc = sysfs_create_file(&ecryptfs_subsys.kset.kobj,
+ &sysfs_attr_version.attr);
+ if (rc) {
+ printk(KERN_ERR
+ "Unable to create ecryptfs version attribute\n");
+ subsystem_unregister(&ecryptfs_subsys);
+ goto out;
+ }
+ rc = sysfs_create_file(&ecryptfs_subsys.kset.kobj,
+ &sysfs_attr_version_str.attr);
+ if (rc) {
+ printk(KERN_ERR
+ "Unable to create ecryptfs version_str attribute\n");
+ sysfs_remove_file(&ecryptfs_subsys.kset.kobj,
+ &sysfs_attr_version.attr);
+ subsystem_unregister(&ecryptfs_subsys);
+ goto out;
+ }
+out:
+ return rc;
+}
+
+static int __init ecryptfs_init(void)
+{
+ int rc;
+
+ if (ECRYPTFS_DEFAULT_EXTENT_SIZE > PAGE_CACHE_SIZE) {
+ rc = -EINVAL;
+ ecryptfs_printk(KERN_ERR, "The eCryptfs extent size is "
+ "larger than the host's page size, and so "
+ "eCryptfs cannot run on this system. The "
+ "default eCryptfs extent size is [%d] bytes; "
+ "the page size is [%d] bytes.\n",
+ ECRYPTFS_DEFAULT_EXTENT_SIZE, PAGE_CACHE_SIZE);
+ goto out;
+ }
+ rc = ecryptfs_init_kmem_caches();
+ if (rc) {
+ printk(KERN_ERR
+ "Failed to allocate one or more kmem_cache objects\n");
+ goto out;
+ }
+ rc = register_filesystem(&ecryptfs_fs_type);
+ if (rc) {
+ printk(KERN_ERR "Failed to register filesystem\n");
+ ecryptfs_free_kmem_caches();
+ goto out;
+ }
+ kset_set_kset_s(&ecryptfs_subsys, fs_subsys);
+ sysfs_attr_version.attr.owner = THIS_MODULE;
+ sysfs_attr_version_str.attr.owner = THIS_MODULE;
+ rc = do_sysfs_registration();
+ if (rc) {
+ printk(KERN_ERR "sysfs registration failed\n");
+ unregister_filesystem(&ecryptfs_fs_type);
+ ecryptfs_free_kmem_caches();
+ goto out;
+ }
+out:
+ return rc;
+}
+
+static void __exit ecryptfs_exit(void)
+{
+ sysfs_remove_file(&ecryptfs_subsys.kset.kobj,
+ &sysfs_attr_version.attr);
+ sysfs_remove_file(&ecryptfs_subsys.kset.kobj,
+ &sysfs_attr_version_str.attr);
+ subsystem_unregister(&ecryptfs_subsys);
+ unregister_filesystem(&ecryptfs_fs_type);
+ ecryptfs_free_kmem_caches();
+}
+
+MODULE_AUTHOR("Michael A. Halcrow <mhalcrow@us.ibm.com>");
+MODULE_DESCRIPTION("eCryptfs");
+
+MODULE_LICENSE("GPL");
+
+module_init(ecryptfs_init)
+module_exit(ecryptfs_exit)
--- /dev/null
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ * This is where eCryptfs coordinates the symmetric encryption and
+ * decryption of the file data as it passes between the lower
+ * encrypted file and the upper decrypted file.
+ *
+ * Copyright (C) 1997-2003 Erez Zadok
+ * Copyright (C) 2001-2003 Stony Brook University
+ * Copyright (C) 2004-2006 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <linux/pagemap.h>
+#include <linux/writeback.h>
+#include <linux/page-flags.h>
+#include <linux/mount.h>
+#include <linux/file.h>
+#include <linux/crypto.h>
+#include <linux/scatterlist.h>
+#include "ecryptfs_kernel.h"
+
+struct kmem_cache *ecryptfs_lower_page_cache;
+
+/**
+ * ecryptfs_get1page
+ *
+ * Get one page from cache or lower f/s, return error otherwise.
+ *
+ * Returns unlocked and up-to-date page (if ok), with increased
+ * refcnt.
+ */
+static struct page *ecryptfs_get1page(struct file *file, int index)
+{
+ struct page *page;
+ struct dentry *dentry;
+ struct inode *inode;
+ struct address_space *mapping;
+
+ dentry = file->f_dentry;
+ inode = dentry->d_inode;
+ mapping = inode->i_mapping;
+ page = read_cache_page(mapping, index,
+ (filler_t *)mapping->a_ops->readpage,
+ (void *)file);
+ if (IS_ERR(page))
+ goto out;
+ wait_on_page_locked(page);
+out:
+ return page;
+}
+
+static
+int write_zeros(struct file *file, pgoff_t index, int start, int num_zeros);
+
+/**
+ * ecryptfs_fill_zeros
+ * @file: The ecryptfs file
+ * @new_length: The new length of the data in the underlying file;
+ * everything between the prior end of the file and the
+ * new end of the file will be filled with zero's.
+ * new_length must be greater than current length
+ *
+ * Function for handling lseek-ing past the end of the file.
+ *
+ * This function does not support shrinking, only growing a file.
+ *
+ * Returns zero on success; non-zero otherwise.
+ */
+int ecryptfs_fill_zeros(struct file *file, loff_t new_length)
+{
+ int rc = 0;
+ struct dentry *dentry = file->f_dentry;
+ struct inode *inode = dentry->d_inode;
+ pgoff_t old_end_page_index = 0;
+ pgoff_t index = old_end_page_index;
+ int old_end_pos_in_page = -1;
+ pgoff_t new_end_page_index;
+ int new_end_pos_in_page;
+ loff_t cur_length = i_size_read(inode);
+
+ if (cur_length != 0) {
+ index = old_end_page_index =
+ ((cur_length - 1) >> PAGE_CACHE_SHIFT);
+ old_end_pos_in_page = ((cur_length - 1) & ~PAGE_CACHE_MASK);
+ }
+ new_end_page_index = ((new_length - 1) >> PAGE_CACHE_SHIFT);
+ new_end_pos_in_page = ((new_length - 1) & ~PAGE_CACHE_MASK);
+ ecryptfs_printk(KERN_DEBUG, "old_end_page_index = [0x%.16x]; "
+ "old_end_pos_in_page = [%d]; "
+ "new_end_page_index = [0x%.16x]; "
+ "new_end_pos_in_page = [%d]\n",
+ old_end_page_index, old_end_pos_in_page,
+ new_end_page_index, new_end_pos_in_page);
+ if (old_end_page_index == new_end_page_index) {
+ /* Start and end are in the same page; we just need to
+ * set a portion of the existing page to zero's */
+ rc = write_zeros(file, index, (old_end_pos_in_page + 1),
+ (new_end_pos_in_page - old_end_pos_in_page));
+ if (rc)
+ ecryptfs_printk(KERN_ERR, "write_zeros(file=[%p], "
+ "index=[0x%.16x], "
+ "old_end_pos_in_page=[d], "
+ "(PAGE_CACHE_SIZE - new_end_pos_in_page"
+ "=[%d]"
+ ")=[d]) returned [%d]\n", file, index,
+ old_end_pos_in_page,
+ new_end_pos_in_page,
+ (PAGE_CACHE_SIZE - new_end_pos_in_page),
+ rc);
+ goto out;
+ }
+ /* Fill the remainder of the previous last page with zeros */
+ rc = write_zeros(file, index, (old_end_pos_in_page + 1),
+ ((PAGE_CACHE_SIZE - 1) - old_end_pos_in_page));
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "write_zeros(file=[%p], "
+ "index=[0x%.16x], old_end_pos_in_page=[d], "
+ "(PAGE_CACHE_SIZE - old_end_pos_in_page)=[d]) "
+ "returned [%d]\n", file, index,
+ old_end_pos_in_page,
+ (PAGE_CACHE_SIZE - old_end_pos_in_page), rc);
+ goto out;
+ }
+ index++;
+ while (index < new_end_page_index) {
+ /* Fill all intermediate pages with zeros */
+ rc = write_zeros(file, index, 0, PAGE_CACHE_SIZE);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "write_zeros(file=[%p], "
+ "index=[0x%.16x], "
+ "old_end_pos_in_page=[d], "
+ "(PAGE_CACHE_SIZE - new_end_pos_in_page"
+ "=[%d]"
+ ")=[d]) returned [%d]\n", file, index,
+ old_end_pos_in_page,
+ new_end_pos_in_page,
+ (PAGE_CACHE_SIZE - new_end_pos_in_page),
+ rc);
+ goto out;
+ }
+ index++;
+ }
+ /* Fill the portion at the beginning of the last new page with
+ * zero's */
+ rc = write_zeros(file, index, 0, (new_end_pos_in_page + 1));
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "write_zeros(file="
+ "[%p], index=[0x%.16x], 0, "
+ "new_end_pos_in_page=[%d]"
+ "returned [%d]\n", file, index,
+ new_end_pos_in_page, rc);
+ goto out;
+ }
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_writepage
+ * @page: Page that is locked before this call is made
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int ecryptfs_writepage(struct page *page, struct writeback_control *wbc)
+{
+ struct ecryptfs_page_crypt_context ctx;
+ int rc;
+
+ ctx.page = page;
+ ctx.mode = ECRYPTFS_WRITEPAGE_MODE;
+ ctx.param.wbc = wbc;
+ rc = ecryptfs_encrypt_page(&ctx);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error encrypting "
+ "page (upper index [0x%.16x])\n", page->index);
+ ClearPageUptodate(page);
+ goto out;
+ }
+ SetPageUptodate(page);
+ unlock_page(page);
+out:
+ return rc;
+}
+
+/**
+ * Reads the data from the lower file file at index lower_page_index
+ * and copies that data into page.
+ *
+ * @param page Page to fill
+ * @param lower_page_index Index of the page in the lower file to get
+ */
+int ecryptfs_do_readpage(struct file *file, struct page *page,
+ pgoff_t lower_page_index)
+{
+ int rc;
+ struct dentry *dentry;
+ struct file *lower_file;
+ struct dentry *lower_dentry;
+ struct inode *inode;
+ struct inode *lower_inode;
+ char *page_data;
+ struct page *lower_page = NULL;
+ char *lower_page_data;
+ const struct address_space_operations *lower_a_ops;
+
+ dentry = file->f_dentry;
+ lower_file = ecryptfs_file_to_lower(file);
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ inode = dentry->d_inode;
+ lower_inode = ecryptfs_inode_to_lower(inode);
+ lower_a_ops = lower_inode->i_mapping->a_ops;
+ lower_page = read_cache_page(lower_inode->i_mapping, lower_page_index,
+ (filler_t *)lower_a_ops->readpage,
+ (void *)lower_file);
+ if (IS_ERR(lower_page)) {
+ rc = PTR_ERR(lower_page);
+ lower_page = NULL;
+ ecryptfs_printk(KERN_ERR, "Error reading from page cache\n");
+ goto out;
+ }
+ wait_on_page_locked(lower_page);
+ page_data = (char *)kmap(page);
+ if (!page_data) {
+ rc = -ENOMEM;
+ ecryptfs_printk(KERN_ERR, "Error mapping page\n");
+ goto out;
+ }
+ lower_page_data = (char *)kmap(lower_page);
+ if (!lower_page_data) {
+ rc = -ENOMEM;
+ ecryptfs_printk(KERN_ERR, "Error mapping page\n");
+ kunmap(page);
+ goto out;
+ }
+ memcpy(page_data, lower_page_data, PAGE_CACHE_SIZE);
+ kunmap(lower_page);
+ kunmap(page);
+ rc = 0;
+out:
+ if (likely(lower_page))
+ page_cache_release(lower_page);
+ if (rc == 0)
+ SetPageUptodate(page);
+ else
+ ClearPageUptodate(page);
+ return rc;
+}
+
+/**
+ * ecryptfs_readpage
+ * @file: This is an ecryptfs file
+ * @page: ecryptfs associated page to stick the read data into
+ *
+ * Read in a page, decrypting if necessary.
+ *
+ * Returns zero on success; non-zero on error.
+ */
+static int ecryptfs_readpage(struct file *file, struct page *page)
+{
+ int rc = 0;
+ struct ecryptfs_crypt_stat *crypt_stat;
+
+ BUG_ON(!(file && file->f_dentry && file->f_dentry->d_inode));
+ crypt_stat =
+ &ecryptfs_inode_to_private(file->f_dentry->d_inode)->crypt_stat;
+ if (!crypt_stat
+ || !ECRYPTFS_CHECK_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED)
+ || ECRYPTFS_CHECK_FLAG(crypt_stat->flags, ECRYPTFS_NEW_FILE)) {
+ ecryptfs_printk(KERN_DEBUG,
+ "Passing through unencrypted page\n");
+ rc = ecryptfs_do_readpage(file, page, page->index);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error reading page; rc = "
+ "[%d]\n", rc);
+ goto out;
+ }
+ } else {
+ rc = ecryptfs_decrypt_page(file, page);
+ if (rc) {
+
+ ecryptfs_printk(KERN_ERR, "Error decrypting page; "
+ "rc = [%d]\n", rc);
+ goto out;
+ }
+ }
+ SetPageUptodate(page);
+out:
+ if (rc)
+ ClearPageUptodate(page);
+ ecryptfs_printk(KERN_DEBUG, "Unlocking page with index = [0x%.16x]\n",
+ page->index);
+ unlock_page(page);
+ return rc;
+}
+
+static int fill_zeros_to_end_of_page(struct page *page, unsigned int to)
+{
+ struct inode *inode = page->mapping->host;
+ int end_byte_in_page;
+ int rc = 0;
+ char *page_virt;
+
+ if ((i_size_read(inode) / PAGE_CACHE_SIZE) == page->index) {
+ end_byte_in_page = i_size_read(inode) % PAGE_CACHE_SIZE;
+ if (to > end_byte_in_page)
+ end_byte_in_page = to;
+ page_virt = kmap(page);
+ if (!page_virt) {
+ rc = -ENOMEM;
+ ecryptfs_printk(KERN_WARNING,
+ "Could not map page\n");
+ goto out;
+ }
+ memset((page_virt + end_byte_in_page), 0,
+ (PAGE_CACHE_SIZE - end_byte_in_page));
+ kunmap(page);
+ }
+out:
+ return rc;
+}
+
+static int ecryptfs_prepare_write(struct file *file, struct page *page,
+ unsigned from, unsigned to)
+{
+ int rc = 0;
+
+ kmap(page);
+ if (from == 0 && to == PAGE_CACHE_SIZE)
+ goto out; /* If we are writing a full page, it will be
+ up to date. */
+ if (!PageUptodate(page))
+ rc = ecryptfs_do_readpage(file, page, page->index);
+out:
+ return rc;
+}
+
+int ecryptfs_grab_and_map_lower_page(struct page **lower_page,
+ char **lower_virt,
+ struct inode *lower_inode,
+ unsigned long lower_page_index)
+{
+ int rc = 0;
+
+ (*lower_page) = grab_cache_page(lower_inode->i_mapping,
+ lower_page_index);
+ if (!(*lower_page)) {
+ ecryptfs_printk(KERN_ERR, "grab_cache_page for "
+ "lower_page_index = [0x%.16x] failed\n",
+ lower_page_index);
+ rc = -EINVAL;
+ goto out;
+ }
+ if (lower_virt)
+ (*lower_virt) = kmap((*lower_page));
+ else
+ kmap((*lower_page));
+out:
+ return rc;
+}
+
+int ecryptfs_writepage_and_release_lower_page(struct page *lower_page,
+ struct inode *lower_inode,
+ struct writeback_control *wbc)
+{
+ int rc = 0;
+
+ rc = lower_inode->i_mapping->a_ops->writepage(lower_page, wbc);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error calling lower writepage(); "
+ "rc = [%d]\n", rc);
+ goto out;
+ }
+ lower_inode->i_mtime = lower_inode->i_ctime = CURRENT_TIME;
+ page_cache_release(lower_page);
+out:
+ return rc;
+}
+
+static void ecryptfs_unmap_and_release_lower_page(struct page *lower_page)
+{
+ kunmap(lower_page);
+ ecryptfs_printk(KERN_DEBUG, "Unlocking lower page with index = "
+ "[0x%.16x]\n", lower_page->index);
+ unlock_page(lower_page);
+ page_cache_release(lower_page);
+}
+
+/**
+ * ecryptfs_write_inode_size_to_header
+ *
+ * Writes the lower file size to the first 8 bytes of the header.
+ *
+ * Returns zero on success; non-zero on error.
+ */
+int
+ecryptfs_write_inode_size_to_header(struct file *lower_file,
+ struct inode *lower_inode,
+ struct inode *inode)
+{
+ int rc = 0;
+ struct page *header_page;
+ char *header_virt;
+ const struct address_space_operations *lower_a_ops;
+ u64 file_size;
+
+ rc = ecryptfs_grab_and_map_lower_page(&header_page, &header_virt,
+ lower_inode, 0);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "grab_cache_page for header page "
+ "failed\n");
+ goto out;
+ }
+ lower_a_ops = lower_inode->i_mapping->a_ops;
+ rc = lower_a_ops->prepare_write(lower_file, header_page, 0, 8);
+ file_size = (u64)i_size_read(inode);
+ ecryptfs_printk(KERN_DEBUG, "Writing size: [0x%.16x]\n", file_size);
+ file_size = cpu_to_be64(file_size);
+ memcpy(header_virt, &file_size, sizeof(u64));
+ rc = lower_a_ops->commit_write(lower_file, header_page, 0, 8);
+ if (rc < 0)
+ ecryptfs_printk(KERN_ERR, "Error commiting header page "
+ "write\n");
+ ecryptfs_unmap_and_release_lower_page(header_page);
+ lower_inode->i_mtime = lower_inode->i_ctime = CURRENT_TIME;
+ mark_inode_dirty_sync(inode);
+out:
+ return rc;
+}
+
+int ecryptfs_get_lower_page(struct page **lower_page, struct inode *lower_inode,
+ struct file *lower_file,
+ unsigned long lower_page_index, int byte_offset,
+ int region_bytes)
+{
+ int rc = 0;
+
+ rc = ecryptfs_grab_and_map_lower_page(lower_page, NULL, lower_inode,
+ lower_page_index);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error attempting to grab and map "
+ "lower page with index [0x%.16x]\n",
+ lower_page_index);
+ goto out;
+ }
+ rc = lower_inode->i_mapping->a_ops->prepare_write(lower_file,
+ (*lower_page),
+ byte_offset,
+ region_bytes);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "prepare_write for "
+ "lower_page_index = [0x%.16x] failed; rc = "
+ "[%d]\n", lower_page_index, rc);
+ }
+out:
+ if (rc && (*lower_page)) {
+ ecryptfs_unmap_and_release_lower_page(*lower_page);
+ (*lower_page) = NULL;
+ }
+ return rc;
+}
+
+/**
+ * ecryptfs_commit_lower_page
+ *
+ * Returns zero on success; non-zero on error
+ */
+int
+ecryptfs_commit_lower_page(struct page *lower_page, struct inode *lower_inode,
+ struct file *lower_file, int byte_offset,
+ int region_size)
+{
+ int rc = 0;
+
+ rc = lower_inode->i_mapping->a_ops->commit_write(
+ lower_file, lower_page, byte_offset, region_size);
+ if (rc < 0) {
+ ecryptfs_printk(KERN_ERR,
+ "Error committing write; rc = [%d]\n", rc);
+ } else
+ rc = 0;
+ ecryptfs_unmap_and_release_lower_page(lower_page);
+ return rc;
+}
+
+/**
+ * ecryptfs_copy_page_to_lower
+ *
+ * Used for plaintext pass-through; no page index interpolation
+ * required.
+ */
+int ecryptfs_copy_page_to_lower(struct page *page, struct inode *lower_inode,
+ struct file *lower_file)
+{
+ int rc = 0;
+ struct page *lower_page;
+
+ rc = ecryptfs_get_lower_page(&lower_page, lower_inode, lower_file,
+ page->index, 0, PAGE_CACHE_SIZE);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error attempting to get page "
+ "at index [0x%.16x]\n", page->index);
+ goto out;
+ }
+ /* TODO: aops */
+ memcpy((char *)page_address(lower_page), page_address(page),
+ PAGE_CACHE_SIZE);
+ rc = ecryptfs_commit_lower_page(lower_page, lower_inode, lower_file,
+ 0, PAGE_CACHE_SIZE);
+ if (rc)
+ ecryptfs_printk(KERN_ERR, "Error attempting to commit page "
+ "at index [0x%.16x]\n", page->index);
+out:
+ return rc;
+}
+
+static int
+process_new_file(struct ecryptfs_crypt_stat *crypt_stat,
+ struct file *file, struct inode *inode)
+{
+ struct page *header_page;
+ const struct address_space_operations *lower_a_ops;
+ struct inode *lower_inode;
+ struct file *lower_file;
+ char *header_virt;
+ int rc = 0;
+ int current_header_page = 0;
+ int header_pages;
+ int more_header_data_to_be_written = 1;
+
+ lower_inode = ecryptfs_inode_to_lower(inode);
+ lower_file = ecryptfs_file_to_lower(file);
+ lower_a_ops = lower_inode->i_mapping->a_ops;
+ header_pages = ((crypt_stat->header_extent_size
+ * crypt_stat->num_header_extents_at_front)
+ / PAGE_CACHE_SIZE);
+ BUG_ON(header_pages < 1);
+ while (current_header_page < header_pages) {
+ rc = ecryptfs_grab_and_map_lower_page(&header_page,
+ &header_virt,
+ lower_inode,
+ current_header_page);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "grab_cache_page for "
+ "header page [%d] failed; rc = [%d]\n",
+ current_header_page, rc);
+ goto out;
+ }
+ rc = lower_a_ops->prepare_write(lower_file, header_page, 0,
+ PAGE_CACHE_SIZE);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error preparing to write "
+ "header page out; rc = [%d]\n", rc);
+ goto out;
+ }
+ memset(header_virt, 0, PAGE_CACHE_SIZE);
+ if (more_header_data_to_be_written) {
+ rc = ecryptfs_write_headers_virt(header_virt,
+ crypt_stat,
+ file->f_dentry);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error "
+ "generating header; rc = "
+ "[%d]\n", rc);
+ rc = -EIO;
+ memset(header_virt, 0, PAGE_CACHE_SIZE);
+ ecryptfs_unmap_and_release_lower_page(
+ header_page);
+ goto out;
+ }
+ if (current_header_page == 0)
+ memset(header_virt, 0, 8);
+ more_header_data_to_be_written = 0;
+ }
+ rc = lower_a_ops->commit_write(lower_file, header_page, 0,
+ PAGE_CACHE_SIZE);
+ ecryptfs_unmap_and_release_lower_page(header_page);
+ if (rc < 0) {
+ ecryptfs_printk(KERN_ERR,
+ "Error commiting header page write; "
+ "rc = [%d]\n", rc);
+ break;
+ }
+ current_header_page++;
+ }
+ if (rc >= 0) {
+ rc = 0;
+ ecryptfs_printk(KERN_DEBUG, "lower_inode->i_blocks = "
+ "[0x%.16x]\n", lower_inode->i_blocks);
+ i_size_write(inode, 0);
+ lower_inode->i_mtime = lower_inode->i_ctime = CURRENT_TIME;
+ mark_inode_dirty_sync(inode);
+ }
+ ecryptfs_printk(KERN_DEBUG, "Clearing ECRYPTFS_NEW_FILE flag in "
+ "crypt_stat at memory location [%p]\n", crypt_stat);
+ ECRYPTFS_CLEAR_FLAG(crypt_stat->flags, ECRYPTFS_NEW_FILE);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_commit_write
+ * @file: The eCryptfs file object
+ * @page: The eCryptfs page
+ * @from: Ignored (we rotate the page IV on each write)
+ * @to: Ignored
+ *
+ * This is where we encrypt the data and pass the encrypted data to
+ * the lower filesystem. In OpenPGP-compatible mode, we operate on
+ * entire underlying packets.
+ */
+static int ecryptfs_commit_write(struct file *file, struct page *page,
+ unsigned from, unsigned to)
+{
+ struct ecryptfs_page_crypt_context ctx;
+ loff_t pos;
+ struct inode *inode;
+ struct inode *lower_inode;
+ struct file *lower_file;
+ struct ecryptfs_crypt_stat *crypt_stat;
+ int rc;
+
+ inode = page->mapping->host;
+ lower_inode = ecryptfs_inode_to_lower(inode);
+ lower_file = ecryptfs_file_to_lower(file);
+ mutex_lock(&lower_inode->i_mutex);
+ crypt_stat =
+ &ecryptfs_inode_to_private(file->f_dentry->d_inode)->crypt_stat;
+ if (ECRYPTFS_CHECK_FLAG(crypt_stat->flags, ECRYPTFS_NEW_FILE)) {
+ ecryptfs_printk(KERN_DEBUG, "ECRYPTFS_NEW_FILE flag set in "
+ "crypt_stat at memory location [%p]\n", crypt_stat);
+ rc = process_new_file(crypt_stat, file, inode);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error processing new "
+ "file; rc = [%d]\n", rc);
+ goto out;
+ }
+ } else
+ ecryptfs_printk(KERN_DEBUG, "Not a new file\n");
+ ecryptfs_printk(KERN_DEBUG, "Calling fill_zeros_to_end_of_page"
+ "(page w/ index = [0x%.16x], to = [%d])\n", page->index,
+ to);
+ rc = fill_zeros_to_end_of_page(page, to);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error attempting to fill "
+ "zeros in page with index = [0x%.16x]\n",
+ page->index);
+ goto out;
+ }
+ ctx.page = page;
+ ctx.mode = ECRYPTFS_PREPARE_COMMIT_MODE;
+ ctx.param.lower_file = lower_file;
+ rc = ecryptfs_encrypt_page(&ctx);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error encrypting page (upper "
+ "index [0x%.16x])\n", page->index);
+ goto out;
+ }
+ rc = 0;
+ inode->i_blocks = lower_inode->i_blocks;
+ pos = (page->index << PAGE_CACHE_SHIFT) + to;
+ if (pos > i_size_read(inode)) {
+ i_size_write(inode, pos);
+ ecryptfs_printk(KERN_DEBUG, "Expanded file size to "
+ "[0x%.16x]\n", i_size_read(inode));
+ }
+ ecryptfs_write_inode_size_to_header(lower_file, lower_inode, inode);
+ lower_inode->i_mtime = lower_inode->i_ctime = CURRENT_TIME;
+ mark_inode_dirty_sync(inode);
+out:
+ kunmap(page); /* mapped in prior call (prepare_write) */
+ if (rc < 0)
+ ClearPageUptodate(page);
+ else
+ SetPageUptodate(page);
+ mutex_unlock(&lower_inode->i_mutex);
+ return rc;
+}
+
+/**
+ * write_zeros
+ * @file: The ecryptfs file
+ * @index: The index in which we are writing
+ * @start: The position after the last block of data
+ * @num_zeros: The number of zeros to write
+ *
+ * Write a specified number of zero's to a page.
+ *
+ * (start + num_zeros) must be less than or equal to PAGE_CACHE_SIZE
+ */
+static
+int write_zeros(struct file *file, pgoff_t index, int start, int num_zeros)
+{
+ int rc = 0;
+ struct page *tmp_page;
+
+ tmp_page = ecryptfs_get1page(file, index);
+ if (IS_ERR(tmp_page)) {
+ ecryptfs_printk(KERN_ERR, "Error getting page at index "
+ "[0x%.16x]\n", index);
+ rc = PTR_ERR(tmp_page);
+ goto out;
+ }
+ kmap(tmp_page);
+ rc = ecryptfs_prepare_write(file, tmp_page, start, start + num_zeros);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error preparing to write zero's "
+ "to remainder of page at index [0x%.16x]\n",
+ index);
+ kunmap(tmp_page);
+ page_cache_release(tmp_page);
+ goto out;
+ }
+ memset(((char *)page_address(tmp_page) + start), 0, num_zeros);
+ rc = ecryptfs_commit_write(file, tmp_page, start, start + num_zeros);
+ if (rc < 0) {
+ ecryptfs_printk(KERN_ERR, "Error attempting to write zero's "
+ "to remainder of page at index [0x%.16x]\n",
+ index);
+ kunmap(tmp_page);
+ page_cache_release(tmp_page);
+ goto out;
+ }
+ rc = 0;
+ kunmap(tmp_page);
+ page_cache_release(tmp_page);
+out:
+ return rc;
+}
+
+static sector_t ecryptfs_bmap(struct address_space *mapping, sector_t block)
+{
+ int rc = 0;
+ struct inode *inode;
+ struct inode *lower_inode;
+
+ inode = (struct inode *)mapping->host;
+ lower_inode = ecryptfs_inode_to_lower(inode);
+ if (lower_inode->i_mapping->a_ops->bmap)
+ rc = lower_inode->i_mapping->a_ops->bmap(lower_inode->i_mapping,
+ block);
+ return rc;
+}
+
+static void ecryptfs_sync_page(struct page *page)
+{
+ struct inode *inode;
+ struct inode *lower_inode;
+ struct page *lower_page;
+
+ inode = page->mapping->host;
+ lower_inode = ecryptfs_inode_to_lower(inode);
+ /* NOTE: Recently swapped with grab_cache_page(), since
+ * sync_page() just makes sure that pending I/O gets done. */
+ lower_page = find_lock_page(lower_inode->i_mapping, page->index);
+ if (!lower_page) {
+ ecryptfs_printk(KERN_DEBUG, "find_lock_page failed\n");
+ return;
+ }
+ lower_page->mapping->a_ops->sync_page(lower_page);
+ ecryptfs_printk(KERN_DEBUG, "Unlocking page with index = [0x%.16x]\n",
+ lower_page->index);
+ unlock_page(lower_page);
+ page_cache_release(lower_page);
+}
+
+struct address_space_operations ecryptfs_aops = {
+ .writepage = ecryptfs_writepage,
+ .readpage = ecryptfs_readpage,
+ .prepare_write = ecryptfs_prepare_write,
+ .commit_write = ecryptfs_commit_write,
+ .bmap = ecryptfs_bmap,
+ .sync_page = ecryptfs_sync_page,
+};
--- /dev/null
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 1997-2003 Erez Zadok
+ * Copyright (C) 2001-2003 Stony Brook University
+ * Copyright (C) 2004-2006 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ * Michael C. Thompson <mcthomps@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/key.h>
+#include <linux/seq_file.h>
+#include <linux/crypto.h>
+#include "ecryptfs_kernel.h"
+
+struct kmem_cache *ecryptfs_inode_info_cache;
+
+/**
+ * ecryptfs_alloc_inode - allocate an ecryptfs inode
+ * @sb: Pointer to the ecryptfs super block
+ *
+ * Called to bring an inode into existence.
+ *
+ * Only handle allocation, setting up structures should be done in
+ * ecryptfs_read_inode. This is because the kernel, between now and
+ * then, will 0 out the private data pointer.
+ *
+ * Returns a pointer to a newly allocated inode, NULL otherwise
+ */
+static struct inode *ecryptfs_alloc_inode(struct super_block *sb)
+{
+ struct ecryptfs_inode_info *ecryptfs_inode;
+ struct inode *inode = NULL;
+
+ ecryptfs_inode = kmem_cache_alloc(ecryptfs_inode_info_cache,
+ SLAB_KERNEL);
+ if (unlikely(!ecryptfs_inode))
+ goto out;
+ ecryptfs_init_crypt_stat(&ecryptfs_inode->crypt_stat);
+ inode = &ecryptfs_inode->vfs_inode;
+out:
+ return inode;
+}
+
+/**
+ * ecryptfs_destroy_inode
+ * @inode: The ecryptfs inode
+ *
+ * This is used during the final destruction of the inode.
+ * All allocation of memory related to the inode, including allocated
+ * memory in the crypt_stat struct, will be released here.
+ * There should be no chance that this deallocation will be missed.
+ */
+static void ecryptfs_destroy_inode(struct inode *inode)
+{
+ struct ecryptfs_inode_info *inode_info;
+
+ inode_info = ecryptfs_inode_to_private(inode);
+ ecryptfs_destruct_crypt_stat(&inode_info->crypt_stat);
+ kmem_cache_free(ecryptfs_inode_info_cache, inode_info);
+}
+
+/**
+ * ecryptfs_init_inode
+ * @inode: The ecryptfs inode
+ *
+ * Set up the ecryptfs inode.
+ */
+void ecryptfs_init_inode(struct inode *inode, struct inode *lower_inode)
+{
+ ecryptfs_set_inode_lower(inode, lower_inode);
+ inode->i_ino = lower_inode->i_ino;
+ inode->i_version++;
+ inode->i_op = &ecryptfs_main_iops;
+ inode->i_fop = &ecryptfs_main_fops;
+ inode->i_mapping->a_ops = &ecryptfs_aops;
+}
+
+/**
+ * ecryptfs_put_super
+ * @sb: Pointer to the ecryptfs super block
+ *
+ * Final actions when unmounting a file system.
+ * This will handle deallocation and release of our private data.
+ */
+static void ecryptfs_put_super(struct super_block *sb)
+{
+ struct ecryptfs_sb_info *sb_info = ecryptfs_superblock_to_private(sb);
+
+ ecryptfs_destruct_mount_crypt_stat(&sb_info->mount_crypt_stat);
+ kmem_cache_free(ecryptfs_sb_info_cache, sb_info);
+ ecryptfs_set_superblock_private(sb, NULL);
+}
+
+/**
+ * ecryptfs_statfs
+ * @sb: The ecryptfs super block
+ * @buf: The struct kstatfs to fill in with stats
+ *
+ * Get the filesystem statistics. Currently, we let this pass right through
+ * to the lower filesystem and take no action ourselves.
+ */
+static int ecryptfs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+ return vfs_statfs(ecryptfs_dentry_to_lower(dentry), buf);
+}
+
+/**
+ * ecryptfs_clear_inode
+ * @inode - The ecryptfs inode
+ *
+ * Called by iput() when the inode reference count reached zero
+ * and the inode is not hashed anywhere. Used to clear anything
+ * that needs to be, before the inode is completely destroyed and put
+ * on the inode free list. We use this to drop out reference to the
+ * lower inode.
+ */
+static void ecryptfs_clear_inode(struct inode *inode)
+{
+ iput(ecryptfs_inode_to_lower(inode));
+}
+
+/**
+ * ecryptfs_umount_begin
+ *
+ * Called in do_umount().
+ */
+static void ecryptfs_umount_begin(struct vfsmount *vfsmnt, int flags)
+{
+ struct vfsmount *lower_mnt =
+ ecryptfs_dentry_to_lower_mnt(vfsmnt->mnt_sb->s_root);
+ struct super_block *lower_sb;
+
+ mntput(lower_mnt);
+ lower_sb = lower_mnt->mnt_sb;
+ if (lower_sb->s_op->umount_begin)
+ lower_sb->s_op->umount_begin(lower_mnt, flags);
+}
+
+/**
+ * ecryptfs_show_options
+ *
+ * Prints the directory we are currently mounted over.
+ * Returns zero on success; non-zero otherwise
+ */
+static int ecryptfs_show_options(struct seq_file *m, struct vfsmount *mnt)
+{
+ struct super_block *sb = mnt->mnt_sb;
+ struct dentry *lower_root_dentry = ecryptfs_dentry_to_lower(sb->s_root);
+ struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(sb->s_root);
+ char *tmp_page;
+ char *path;
+ int rc = 0;
+
+ tmp_page = (char *)__get_free_page(GFP_KERNEL);
+ if (!tmp_page) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ path = d_path(lower_root_dentry, lower_mnt, tmp_page, PAGE_SIZE);
+ if (IS_ERR(path)) {
+ rc = PTR_ERR(path);
+ goto out;
+ }
+ seq_printf(m, ",dir=%s", path);
+ free_page((unsigned long)tmp_page);
+out:
+ return rc;
+}
+
+struct super_operations ecryptfs_sops = {
+ .alloc_inode = ecryptfs_alloc_inode,
+ .destroy_inode = ecryptfs_destroy_inode,
+ .drop_inode = generic_delete_inode,
+ .put_super = ecryptfs_put_super,
+ .statfs = ecryptfs_statfs,
+ .remount_fs = NULL,
+ .clear_inode = ecryptfs_clear_inode,
+ .umount_begin = ecryptfs_umount_begin,
+ .show_options = ecryptfs_show_options
+};
projects / deliverable / linux.git / commitdiff
