[deliverable/linux.git] / fs / cifs / smb2transport.c

/*
 *   fs/cifs/smb2transport.c
 *
 *   Copyright (C) International Business Machines  Corp., 2002, 2011
 *                 Etersoft, 2012
 *   Author(s): Steve French (sfrench@us.ibm.com)
 *              Jeremy Allison (jra@samba.org) 2006
 *              Pavel Shilovsky (pshilovsky@samba.org) 2012
 *
 *   This library is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU Lesser General Public License as published
 *   by the Free Software Foundation; either version 2.1 of the License, or
 *   (at your option) any later version.
 *
 *   This library 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 Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public License
 *   along with this library; 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/list.h>
#include <linux/wait.h>
#include <linux/net.h>
#include <linux/delay.h>
#include <linux/uaccess.h>
#include <asm/processor.h>
#include <linux/mempool.h>
#include <linux/highmem.h>
#include "smb2pdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "smb2proto.h"
#include "cifs_debug.h"
#include "smb2status.h"
#include "smb2glob.h"

static int
smb2_crypto_shash_allocate(struct TCP_Server_Info *server)
{
	int rc;
	unsigned int size;

	if (server->secmech.sdeschmacsha256 != NULL)
		return 0; /* already allocated */

	server->secmech.hmacsha256 = crypto_alloc_shash("hmac(sha256)", 0, 0);
	if (IS_ERR(server->secmech.hmacsha256)) {
		cifs_dbg(VFS, "could not allocate crypto hmacsha256\n");
		rc = PTR_ERR(server->secmech.hmacsha256);
		server->secmech.hmacsha256 = NULL;
		return rc;
	}

	size = sizeof(struct shash_desc) +
			crypto_shash_descsize(server->secmech.hmacsha256);
	server->secmech.sdeschmacsha256 = kmalloc(size, GFP_KERNEL);
	if (!server->secmech.sdeschmacsha256) {
		crypto_free_shash(server->secmech.hmacsha256);
		server->secmech.hmacsha256 = NULL;
		return -ENOMEM;
	}
	server->secmech.sdeschmacsha256->shash.tfm = server->secmech.hmacsha256;
	server->secmech.sdeschmacsha256->shash.flags = 0x0;

	return 0;
}

static int
smb3_crypto_shash_allocate(struct TCP_Server_Info *server)
{
	unsigned int size;
	int rc;

	if (server->secmech.sdesccmacaes != NULL)
		return 0;  /* already allocated */

	rc = smb2_crypto_shash_allocate(server);
	if (rc)
		return rc;

	server->secmech.cmacaes = crypto_alloc_shash("cmac(aes)", 0, 0);
	if (IS_ERR(server->secmech.cmacaes)) {
		cifs_dbg(VFS, "could not allocate crypto cmac-aes");
		kfree(server->secmech.sdeschmacsha256);
		server->secmech.sdeschmacsha256 = NULL;
		crypto_free_shash(server->secmech.hmacsha256);
		server->secmech.hmacsha256 = NULL;
		rc = PTR_ERR(server->secmech.cmacaes);
		server->secmech.cmacaes = NULL;
		return rc;
	}

	size = sizeof(struct shash_desc) +
			crypto_shash_descsize(server->secmech.cmacaes);
	server->secmech.sdesccmacaes = kmalloc(size, GFP_KERNEL);
	if (!server->secmech.sdesccmacaes) {
		cifs_dbg(VFS, "%s: Can't alloc cmacaes\n", __func__);
		kfree(server->secmech.sdeschmacsha256);
		server->secmech.sdeschmacsha256 = NULL;
		crypto_free_shash(server->secmech.hmacsha256);
		crypto_free_shash(server->secmech.cmacaes);
		server->secmech.hmacsha256 = NULL;
		server->secmech.cmacaes = NULL;
		return -ENOMEM;
	}
	server->secmech.sdesccmacaes->shash.tfm = server->secmech.cmacaes;
	server->secmech.sdesccmacaes->shash.flags = 0x0;

	return 0;
}

static struct cifs_ses *
smb2_find_smb_ses(struct smb2_hdr *smb2hdr, struct TCP_Server_Info *server)
{
	struct cifs_ses *ses;

	spin_lock(&cifs_tcp_ses_lock);
	list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
		if (ses->Suid != smb2hdr->SessionId)
			continue;
		spin_unlock(&cifs_tcp_ses_lock);
		return ses;
	}
	spin_unlock(&cifs_tcp_ses_lock);

	return NULL;
}


int
smb2_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
{
	int i, rc;
	unsigned char smb2_signature[SMB2_HMACSHA256_SIZE];
	unsigned char *sigptr = smb2_signature;
	struct kvec *iov = rqst->rq_iov;
	int n_vec = rqst->rq_nvec;
	struct smb2_hdr *smb2_pdu = (struct smb2_hdr *)iov[0].iov_base;
	struct cifs_ses *ses;

	ses = smb2_find_smb_ses(smb2_pdu, server);
	if (!ses) {
		cifs_dbg(VFS, "%s: Could not find session\n", __func__);
		return 0;
	}

	memset(smb2_signature, 0x0, SMB2_HMACSHA256_SIZE);
	memset(smb2_pdu->Signature, 0x0, SMB2_SIGNATURE_SIZE);

	rc = smb2_crypto_shash_allocate(server);
	if (rc) {
		cifs_dbg(VFS, "%s: shah256 alloc failed\n", __func__);
		return rc;
	}

	rc = crypto_shash_setkey(server->secmech.hmacsha256,
		ses->auth_key.response, SMB2_NTLMV2_SESSKEY_SIZE);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
		return rc;
	}

	rc = crypto_shash_init(&server->secmech.sdeschmacsha256->shash);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not init sha256", __func__);
		return rc;
	}

	for (i = 0; i < n_vec; i++) {
		if (iov[i].iov_len == 0)
			continue;
		if (iov[i].iov_base == NULL) {
			cifs_dbg(VFS, "null iovec entry\n");
			return -EIO;
		}
		/*
		 * The first entry includes a length field (which does not get
		 * signed that occupies the first 4 bytes before the header).
		 */
		if (i == 0) {
			if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
				break; /* nothing to sign or corrupt header */
			rc =
			crypto_shash_update(
				&server->secmech.sdeschmacsha256->shash,
				iov[i].iov_base + 4, iov[i].iov_len - 4);
		} else {
			rc =
			crypto_shash_update(
				&server->secmech.sdeschmacsha256->shash,
				iov[i].iov_base, iov[i].iov_len);
		}
		if (rc) {
			cifs_dbg(VFS, "%s: Could not update with payload\n",
				 __func__);
			return rc;
		}
	}

	/* now hash over the rq_pages array */
	for (i = 0; i < rqst->rq_npages; i++) {
		struct kvec p_iov;

		cifs_rqst_page_to_kvec(rqst, i, &p_iov);
		crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
					p_iov.iov_base, p_iov.iov_len);
		kunmap(rqst->rq_pages[i]);
	}

	rc = crypto_shash_final(&server->secmech.sdeschmacsha256->shash,
				sigptr);
	if (rc)
		cifs_dbg(VFS, "%s: Could not generate sha256 hash\n", __func__);

	memcpy(smb2_pdu->Signature, sigptr, SMB2_SIGNATURE_SIZE);

	return rc;
}

int
generate_smb3signingkey(struct cifs_ses *ses)
{
	unsigned char zero = 0x0;
	__u8 i[4] = {0, 0, 0, 1};
	__u8 L[4] = {0, 0, 0, 128};
	int rc = 0;
	unsigned char prfhash[SMB2_HMACSHA256_SIZE];
	unsigned char *hashptr = prfhash;

	memset(prfhash, 0x0, SMB2_HMACSHA256_SIZE);
	memset(ses->smb3signingkey, 0x0, SMB3_SIGNKEY_SIZE);

	rc = smb3_crypto_shash_allocate(ses->server);
	if (rc) {
		cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__);
		goto smb3signkey_ret;
	}

	rc = crypto_shash_setkey(ses->server->secmech.hmacsha256,
		ses->auth_key.response, SMB2_NTLMV2_SESSKEY_SIZE);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not set with session key\n", __func__);
		goto smb3signkey_ret;
	}

	rc = crypto_shash_init(&ses->server->secmech.sdeschmacsha256->shash);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not init sign hmac\n", __func__);
		goto smb3signkey_ret;
	}

	rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
				i, 4);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not update with n\n", __func__);
		goto smb3signkey_ret;
	}

	rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
				"SMB2AESCMAC", 12);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not update with label\n", __func__);
		goto smb3signkey_ret;
	}

	rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
				&zero, 1);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not update with zero\n", __func__);
		goto smb3signkey_ret;
	}

	rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
				"SmbSign", 8);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not update with context\n", __func__);
		goto smb3signkey_ret;
	}

	rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
				L, 4);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not update with L\n", __func__);
		goto smb3signkey_ret;
	}

	rc = crypto_shash_final(&ses->server->secmech.sdeschmacsha256->shash,
				hashptr);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not generate sha256 hash\n", __func__);
		goto smb3signkey_ret;
	}

	memcpy(ses->smb3signingkey, hashptr, SMB3_SIGNKEY_SIZE);

smb3signkey_ret:
	return rc;
}

int
smb3_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
{
	int i;
	int rc = 0;
	unsigned char smb3_signature[SMB2_CMACAES_SIZE];
	unsigned char *sigptr = smb3_signature;
	struct kvec *iov = rqst->rq_iov;
	int n_vec = rqst->rq_nvec;
	struct smb2_hdr *smb2_pdu = (struct smb2_hdr *)iov[0].iov_base;
	struct cifs_ses *ses;

	ses = smb2_find_smb_ses(smb2_pdu, server);
	if (!ses) {
		cifs_dbg(VFS, "%s: Could not find session\n", __func__);
		return 0;
	}

	memset(smb3_signature, 0x0, SMB2_CMACAES_SIZE);
	memset(smb2_pdu->Signature, 0x0, SMB2_SIGNATURE_SIZE);

	rc = crypto_shash_setkey(server->secmech.cmacaes,
		ses->smb3signingkey, SMB2_CMACAES_SIZE);

	if (rc) {
		cifs_dbg(VFS, "%s: Could not set key for cmac aes\n", __func__);
		return rc;
	}

	/*
	 * we already allocate sdesccmacaes when we init smb3 signing key,
	 * so unlike smb2 case we do not have to check here if secmech are
	 * initialized
	 */
	rc = crypto_shash_init(&server->secmech.sdesccmacaes->shash);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not init cmac aes\n", __func__);
		return rc;
	}

	for (i = 0; i < n_vec; i++) {
		if (iov[i].iov_len == 0)
			continue;
		if (iov[i].iov_base == NULL) {
			cifs_dbg(VFS, "null iovec entry");
			return -EIO;
		}
		/*
		 * The first entry includes a length field (which does not get
		 * signed that occupies the first 4 bytes before the header).
		 */
		if (i == 0) {
			if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
				break; /* nothing to sign or corrupt header */
			rc =
			crypto_shash_update(
				&server->secmech.sdesccmacaes->shash,
				iov[i].iov_base + 4, iov[i].iov_len - 4);
		} else {
			rc =
			crypto_shash_update(
				&server->secmech.sdesccmacaes->shash,
				iov[i].iov_base, iov[i].iov_len);
		}
		if (rc) {
			cifs_dbg(VFS, "%s: Couldn't update cmac aes with payload\n",
							__func__);
			return rc;
		}
	}

	/* now hash over the rq_pages array */
	for (i = 0; i < rqst->rq_npages; i++) {
		struct kvec p_iov;

		cifs_rqst_page_to_kvec(rqst, i, &p_iov);
		crypto_shash_update(&server->secmech.sdesccmacaes->shash,
					p_iov.iov_base, p_iov.iov_len);
		kunmap(rqst->rq_pages[i]);
	}

	rc = crypto_shash_final(&server->secmech.sdesccmacaes->shash,
						sigptr);
	if (rc)
		cifs_dbg(VFS, "%s: Could not generate cmac aes\n", __func__);

	memcpy(smb2_pdu->Signature, sigptr, SMB2_SIGNATURE_SIZE);

	return rc;
}

/* must be called with server->srv_mutex held */
static int
smb2_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server)
{
	int rc = 0;
	struct smb2_hdr *smb2_pdu = rqst->rq_iov[0].iov_base;

	if (!(smb2_pdu->Flags & SMB2_FLAGS_SIGNED) ||
	    server->tcpStatus == CifsNeedNegotiate)
		return rc;

	if (!server->session_estab) {
		strncpy(smb2_pdu->Signature, "BSRSPYL", 8);
		return rc;
	}

	rc = server->ops->calc_signature(rqst, server);

	return rc;
}

int
smb2_verify_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
{
	unsigned int rc;
	char server_response_sig[16];
	struct smb2_hdr *smb2_pdu = (struct smb2_hdr *)rqst->rq_iov[0].iov_base;

	if ((smb2_pdu->Command == SMB2_NEGOTIATE) ||
	    (smb2_pdu->Command == SMB2_SESSION_SETUP) ||
	    (smb2_pdu->Command == SMB2_OPLOCK_BREAK) ||
	    (!server->session_estab))
		return 0;

	/*
	 * BB what if signatures are supposed to be on for session but
	 * server does not send one? BB
	 */

	/* Do not need to verify session setups with signature "BSRSPYL " */
	if (memcmp(smb2_pdu->Signature, "BSRSPYL ", 8) == 0)
		cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
			 smb2_pdu->Command);

	/*
	 * Save off the origiginal signature so we can modify the smb and check
	 * our calculated signature against what the server sent.
	 */
	memcpy(server_response_sig, smb2_pdu->Signature, SMB2_SIGNATURE_SIZE);

	memset(smb2_pdu->Signature, 0, SMB2_SIGNATURE_SIZE);

	mutex_lock(&server->srv_mutex);
	rc = server->ops->calc_signature(rqst, server);
	mutex_unlock(&server->srv_mutex);

	if (rc)
		return rc;

	if (memcmp(server_response_sig, smb2_pdu->Signature,
		   SMB2_SIGNATURE_SIZE))
		return -EACCES;
	else
		return 0;
}

/*
 * Set message id for the request. Should be called after wait_for_free_request
 * and when srv_mutex is held.
 */
static inline void
smb2_seq_num_into_buf(struct TCP_Server_Info *server, struct smb2_hdr *hdr)
{
	unsigned int i, num = le16_to_cpu(hdr->CreditCharge);

	hdr->MessageId = get_next_mid64(server);
	/* skip message numbers according to CreditCharge field */
	for (i = 1; i < num; i++)
		get_next_mid(server);
}

static struct mid_q_entry *
smb2_mid_entry_alloc(const struct smb2_hdr *smb_buffer,
		     struct TCP_Server_Info *server)
{
	struct mid_q_entry *temp;

	if (server == NULL) {
		cifs_dbg(VFS, "Null TCP session in smb2_mid_entry_alloc\n");
		return NULL;
	}

	temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
	if (temp == NULL)
		return temp;
	else {
		memset(temp, 0, sizeof(struct mid_q_entry));
		temp->mid = smb_buffer->MessageId;	/* always LE */
		temp->pid = current->pid;
		temp->command = smb_buffer->Command;	/* Always LE */
		temp->when_alloc = jiffies;
		temp->server = server;

		/*
		 * The default is for the mid to be synchronous, so the
		 * default callback just wakes up the current task.
		 */
		temp->callback = cifs_wake_up_task;
		temp->callback_data = current;
	}

	atomic_inc(&midCount);
	temp->mid_state = MID_REQUEST_ALLOCATED;
	return temp;
}

static int
smb2_get_mid_entry(struct cifs_ses *ses, struct smb2_hdr *buf,
		   struct mid_q_entry **mid)
{
	if (ses->server->tcpStatus == CifsExiting)
		return -ENOENT;

	if (ses->server->tcpStatus == CifsNeedReconnect) {
		cifs_dbg(FYI, "tcp session dead - return to caller to retry\n");
		return -EAGAIN;
	}

	if (ses->status == CifsNew) {
		if ((buf->Command != SMB2_SESSION_SETUP) &&
		    (buf->Command != SMB2_NEGOTIATE))
			return -EAGAIN;
		/* else ok - we are setting up session */
	}

	if (ses->status == CifsExiting) {
		if (buf->Command != SMB2_LOGOFF)
			return -EAGAIN;
		/* else ok - we are shutting down the session */
	}

	*mid = smb2_mid_entry_alloc(buf, ses->server);
	if (*mid == NULL)
		return -ENOMEM;
	spin_lock(&GlobalMid_Lock);
	list_add_tail(&(*mid)->qhead, &ses->server->pending_mid_q);
	spin_unlock(&GlobalMid_Lock);
	return 0;
}

int
smb2_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
		   bool log_error)
{
	unsigned int len = get_rfc1002_length(mid->resp_buf);
	struct kvec iov;
	struct smb_rqst rqst = { .rq_iov = &iov,
				 .rq_nvec = 1 };

	iov.iov_base = (char *)mid->resp_buf;
	iov.iov_len = get_rfc1002_length(mid->resp_buf) + 4;

	dump_smb(mid->resp_buf, min_t(u32, 80, len));
	/* convert the length into a more usable form */
	if (len > 24 && server->sign) {
		int rc;

		rc = smb2_verify_signature(&rqst, server);
		if (rc)
			cifs_dbg(VFS, "SMB signature verification returned error = %d\n",
				 rc);
	}

	return map_smb2_to_linux_error(mid->resp_buf, log_error);
}

struct mid_q_entry *
smb2_setup_request(struct cifs_ses *ses, struct smb_rqst *rqst)
{
	int rc;
	struct smb2_hdr *hdr = (struct smb2_hdr *)rqst->rq_iov[0].iov_base;
	struct mid_q_entry *mid;

	smb2_seq_num_into_buf(ses->server, hdr);

	rc = smb2_get_mid_entry(ses, hdr, &mid);
	if (rc)
		return ERR_PTR(rc);
	rc = smb2_sign_rqst(rqst, ses->server);
	if (rc) {
		cifs_delete_mid(mid);
		return ERR_PTR(rc);
	}
	return mid;
}

struct mid_q_entry *
smb2_setup_async_request(struct TCP_Server_Info *server, struct smb_rqst *rqst)
{
	int rc;
	struct smb2_hdr *hdr = (struct smb2_hdr *)rqst->rq_iov[0].iov_base;
	struct mid_q_entry *mid;

	smb2_seq_num_into_buf(server, hdr);

	mid = smb2_mid_entry_alloc(hdr, server);
	if (mid == NULL)
		return ERR_PTR(-ENOMEM);

	rc = smb2_sign_rqst(rqst, server);
	if (rc) {
		DeleteMidQEntry(mid);
		return ERR_PTR(rc);
	}

	return mid;
}
Commit	Line	Data
2dc7e1c0 PS	1	/*
	2	* fs/cifs/smb2transport.c
	3	*
	4	* Copyright (C) International Business Machines Corp., 2002, 2011
	5	* Etersoft, 2012
	6	* Author(s): Steve French (sfrench@us.ibm.com)
	7	* Jeremy Allison (jra@samba.org) 2006
	8	* Pavel Shilovsky (pshilovsky@samba.org) 2012
	9	*
	10	* This library is free software; you can redistribute it and/or modify
	11	* it under the terms of the GNU Lesser General Public License as published
	12	* by the Free Software Foundation; either version 2.1 of the License, or
	13	* (at your option) any later version.
	14	*
	15	* This library is distributed in the hope that it will be useful,
	16	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
	18	* the GNU Lesser General Public License for more details.
	19	*
	20	* You should have received a copy of the GNU Lesser General Public License
	21	* along with this library; if not, write to the Free Software
	22	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	23	*/
	24
	25	#include <linux/fs.h>
	26	#include <linux/list.h>
	27	#include <linux/wait.h>
	28	#include <linux/net.h>
	29	#include <linux/delay.h>
	30	#include <linux/uaccess.h>
	31	#include <asm/processor.h>
	32	#include <linux/mempool.h>
fb308a6f	33	#include <linux/highmem.h>
2dc7e1c0 PS	34	#include "smb2pdu.h"
	35	#include "cifsglob.h"
	36	#include "cifsproto.h"
	37	#include "smb2proto.h"
	38	#include "cifs_debug.h"
	39	#include "smb2status.h"
3c1bf7e4 PS	40	#include "smb2glob.h"
3c1bf7e4 PS	41
95dc8dd1 SF	42	static int
	43	smb2_crypto_shash_allocate(struct TCP_Server_Info *server)
	44	{
ba482029	45	int rc;
95dc8dd1 SF	46	unsigned int size;
	47
	48	if (server->secmech.sdeschmacsha256 != NULL)
	49	return 0; /* already allocated */
	50
	51	server->secmech.hmacsha256 = crypto_alloc_shash("hmac(sha256)", 0, 0);
	52	if (IS_ERR(server->secmech.hmacsha256)) {
	53	cifs_dbg(VFS, "could not allocate crypto hmacsha256\n");
ba482029 JL	54	rc = PTR_ERR(server->secmech.hmacsha256);
	55	server->secmech.hmacsha256 = NULL;
	56	return rc;
95dc8dd1 SF	57	}
	58
	59	size = sizeof(struct shash_desc) +
	60	crypto_shash_descsize(server->secmech.hmacsha256);
	61	server->secmech.sdeschmacsha256 = kmalloc(size, GFP_KERNEL);
	62	if (!server->secmech.sdeschmacsha256) {
	63	crypto_free_shash(server->secmech.hmacsha256);
	64	server->secmech.hmacsha256 = NULL;
	65	return -ENOMEM;
	66	}
	67	server->secmech.sdeschmacsha256->shash.tfm = server->secmech.hmacsha256;
	68	server->secmech.sdeschmacsha256->shash.flags = 0x0;
	69
	70	return 0;
	71	}
	72
	73	static int
	74	smb3_crypto_shash_allocate(struct TCP_Server_Info *server)
	75	{
	76	unsigned int size;
	77	int rc;
	78
	79	if (server->secmech.sdesccmacaes != NULL)
	80	return 0; /* already allocated */
	81
	82	rc = smb2_crypto_shash_allocate(server);
	83	if (rc)
	84	return rc;
	85
	86	server->secmech.cmacaes = crypto_alloc_shash("cmac(aes)", 0, 0);
	87	if (IS_ERR(server->secmech.cmacaes)) {
	88	cifs_dbg(VFS, "could not allocate crypto cmac-aes");
	89	kfree(server->secmech.sdeschmacsha256);
	90	server->secmech.sdeschmacsha256 = NULL;
	91	crypto_free_shash(server->secmech.hmacsha256);
	92	server->secmech.hmacsha256 = NULL;
ba482029 JL	93	rc = PTR_ERR(server->secmech.cmacaes);
	94	server->secmech.cmacaes = NULL;
	95	return rc;
95dc8dd1 SF	96	}
	97
	98	size = sizeof(struct shash_desc) +
	99	crypto_shash_descsize(server->secmech.cmacaes);
	100	server->secmech.sdesccmacaes = kmalloc(size, GFP_KERNEL);
	101	if (!server->secmech.sdesccmacaes) {
	102	cifs_dbg(VFS, "%s: Can't alloc cmacaes\n", __func__);
	103	kfree(server->secmech.sdeschmacsha256);
	104	server->secmech.sdeschmacsha256 = NULL;
	105	crypto_free_shash(server->secmech.hmacsha256);
	106	crypto_free_shash(server->secmech.cmacaes);
	107	server->secmech.hmacsha256 = NULL;
	108	server->secmech.cmacaes = NULL;
	109	return -ENOMEM;
	110	}
	111	server->secmech.sdesccmacaes->shash.tfm = server->secmech.cmacaes;
	112	server->secmech.sdesccmacaes->shash.flags = 0x0;
	113
	114	return 0;
	115	}
	116
32811d24 SP	117	static struct cifs_ses *
	118	smb2_find_smb_ses(struct smb2_hdr smb2hdr, struct TCP_Server_Info server)
	119	{
	120	struct cifs_ses *ses;
	121
	122	spin_lock(&cifs_tcp_ses_lock);
	123	list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
	124	if (ses->Suid != smb2hdr->SessionId)
	125	continue;
	126	spin_unlock(&cifs_tcp_ses_lock);
	127	return ses;
	128	}
	129	spin_unlock(&cifs_tcp_ses_lock);
	130
	131	return NULL;
	132	}
	133
95dc8dd1	134
38107d45	135	int
0b688cfc	136	smb2_calc_signature(struct smb_rqst rqst, struct TCP_Server_Info server)
3c1bf7e4 PS	137	{
	138	int i, rc;
	139	unsigned char smb2_signature[SMB2_HMACSHA256_SIZE];
	140	unsigned char *sigptr = smb2_signature;
0b688cfc JL	141	struct kvec *iov = rqst->rq_iov;
0b688cfc JL	142	int n_vec = rqst->rq_nvec;
3c1bf7e4	143	struct smb2_hdr smb2_pdu = (struct smb2_hdr )iov[0].iov_base;
32811d24 SP	144	struct cifs_ses *ses;
	145
	146	ses = smb2_find_smb_ses(smb2_pdu, server);
	147	if (!ses) {
	148	cifs_dbg(VFS, "%s: Could not find session\n", __func__);
	149	return 0;
	150	}
3c1bf7e4 PS	151
	152	memset(smb2_signature, 0x0, SMB2_HMACSHA256_SIZE);
	153	memset(smb2_pdu->Signature, 0x0, SMB2_SIGNATURE_SIZE);
	154
95dc8dd1 SF	155	rc = smb2_crypto_shash_allocate(server);
	156	if (rc) {
	157	cifs_dbg(VFS, "%s: shah256 alloc failed\n", __func__);
	158	return rc;
	159	}
	160
3c1bf7e4	161	rc = crypto_shash_setkey(server->secmech.hmacsha256,
32811d24	162	ses->auth_key.response, SMB2_NTLMV2_SESSKEY_SIZE);
3c1bf7e4	163	if (rc) {
f96637be	164	cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
3c1bf7e4 PS	165	return rc;
	166	}
	167
	168	rc = crypto_shash_init(&server->secmech.sdeschmacsha256->shash);
	169	if (rc) {
95dc8dd1	170	cifs_dbg(VFS, "%s: Could not init sha256", __func__);
3c1bf7e4 PS	171	return rc;
	172	}
	173
	174	for (i = 0; i < n_vec; i++) {
	175	if (iov[i].iov_len == 0)
	176	continue;
	177	if (iov[i].iov_base == NULL) {
f96637be	178	cifs_dbg(VFS, "null iovec entry\n");
3c1bf7e4 PS	179	return -EIO;
	180	}
	181	/*
	182	* The first entry includes a length field (which does not get
	183	* signed that occupies the first 4 bytes before the header).
	184	*/
	185	if (i == 0) {
	186	if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
	187	break; /* nothing to sign or corrupt header */
	188	rc =
	189	crypto_shash_update(
	190	&server->secmech.sdeschmacsha256->shash,
	191	iov[i].iov_base + 4, iov[i].iov_len - 4);
	192	} else {
	193	rc =
	194	crypto_shash_update(
	195	&server->secmech.sdeschmacsha256->shash,
	196	iov[i].iov_base, iov[i].iov_len);
	197	}
	198	if (rc) {
f96637be JP	199	cifs_dbg(VFS, "%s: Could not update with payload\n",
f96637be JP	200	__func__);
3c1bf7e4 PS	201	return rc;
	202	}
	203	}
	204
fb308a6f JL	205	/* now hash over the rq_pages array */
	206	for (i = 0; i < rqst->rq_npages; i++) {
	207	struct kvec p_iov;
	208
	209	cifs_rqst_page_to_kvec(rqst, i, &p_iov);
	210	crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
	211	p_iov.iov_base, p_iov.iov_len);
	212	kunmap(rqst->rq_pages[i]);
	213	}
	214
3c1bf7e4 PS	215	rc = crypto_shash_final(&server->secmech.sdeschmacsha256->shash,
	216	sigptr);
	217	if (rc)
f96637be	218	cifs_dbg(VFS, "%s: Could not generate sha256 hash\n", __func__);
3c1bf7e4 PS	219
	220	memcpy(smb2_pdu->Signature, sigptr, SMB2_SIGNATURE_SIZE);
	221
	222	return rc;
	223	}
	224
32811d24 SP	225	int
32811d24 SP	226	generate_smb3signingkey(struct cifs_ses *ses)
429b46f4 SF	227	{
	228	unsigned char zero = 0x0;
	229	__u8 i[4] = {0, 0, 0, 1};
	230	__u8 L[4] = {0, 0, 0, 128};
	231	int rc = 0;
	232	unsigned char prfhash[SMB2_HMACSHA256_SIZE];
	233	unsigned char *hashptr = prfhash;
	234
	235	memset(prfhash, 0x0, SMB2_HMACSHA256_SIZE);
32811d24	236	memset(ses->smb3signingkey, 0x0, SMB3_SIGNKEY_SIZE);
429b46f4	237
32811d24	238	rc = smb3_crypto_shash_allocate(ses->server);
95dc8dd1 SF	239	if (rc) {
	240	cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__);
	241	goto smb3signkey_ret;
	242	}
	243
32811d24 SP	244	rc = crypto_shash_setkey(ses->server->secmech.hmacsha256,
32811d24 SP	245	ses->auth_key.response, SMB2_NTLMV2_SESSKEY_SIZE);
429b46f4 SF	246	if (rc) {
	247	cifs_dbg(VFS, "%s: Could not set with session key\n", __func__);
	248	goto smb3signkey_ret;
	249	}
	250
32811d24	251	rc = crypto_shash_init(&ses->server->secmech.sdeschmacsha256->shash);
429b46f4 SF	252	if (rc) {
	253	cifs_dbg(VFS, "%s: Could not init sign hmac\n", __func__);
	254	goto smb3signkey_ret;
	255	}
	256
32811d24	257	rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
429b46f4 SF	258	i, 4);
	259	if (rc) {
	260	cifs_dbg(VFS, "%s: Could not update with n\n", __func__);
	261	goto smb3signkey_ret;
	262	}
	263
32811d24	264	rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
429b46f4 SF	265	"SMB2AESCMAC", 12);
	266	if (rc) {
	267	cifs_dbg(VFS, "%s: Could not update with label\n", __func__);
	268	goto smb3signkey_ret;
	269	}
	270
32811d24	271	rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
429b46f4 SF	272	&zero, 1);
	273	if (rc) {
	274	cifs_dbg(VFS, "%s: Could not update with zero\n", __func__);
	275	goto smb3signkey_ret;
	276	}
	277
32811d24	278	rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
429b46f4 SF	279	"SmbSign", 8);
	280	if (rc) {
	281	cifs_dbg(VFS, "%s: Could not update with context\n", __func__);
	282	goto smb3signkey_ret;
	283	}
	284
32811d24	285	rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
429b46f4 SF	286	L, 4);
	287	if (rc) {
	288	cifs_dbg(VFS, "%s: Could not update with L\n", __func__);
	289	goto smb3signkey_ret;
	290	}
	291
32811d24	292	rc = crypto_shash_final(&ses->server->secmech.sdeschmacsha256->shash,
429b46f4 SF	293	hashptr);
	294	if (rc) {
	295	cifs_dbg(VFS, "%s: Could not generate sha256 hash\n", __func__);
	296	goto smb3signkey_ret;
	297	}
	298
32811d24	299	memcpy(ses->smb3signingkey, hashptr, SMB3_SIGNKEY_SIZE);
429b46f4 SF	300
429b46f4 SF	301	smb3signkey_ret:
32811d24	302	return rc;
429b46f4 SF	303	}
429b46f4 SF	304
38107d45 SF	305	int
	306	smb3_calc_signature(struct smb_rqst rqst, struct TCP_Server_Info server)
	307	{
32811d24 SP	308	int i;
32811d24 SP	309	int rc = 0;
429b46f4 SF	310	unsigned char smb3_signature[SMB2_CMACAES_SIZE];
	311	unsigned char *sigptr = smb3_signature;
	312	struct kvec *iov = rqst->rq_iov;
	313	int n_vec = rqst->rq_nvec;
	314	struct smb2_hdr smb2_pdu = (struct smb2_hdr )iov[0].iov_base;
32811d24 SP	315	struct cifs_ses *ses;
	316
	317	ses = smb2_find_smb_ses(smb2_pdu, server);
	318	if (!ses) {
	319	cifs_dbg(VFS, "%s: Could not find session\n", __func__);
	320	return 0;
	321	}
429b46f4 SF	322
	323	memset(smb3_signature, 0x0, SMB2_CMACAES_SIZE);
	324	memset(smb2_pdu->Signature, 0x0, SMB2_SIGNATURE_SIZE);
	325
	326	rc = crypto_shash_setkey(server->secmech.cmacaes,
32811d24 SP	327	ses->smb3signingkey, SMB2_CMACAES_SIZE);
32811d24 SP	328
429b46f4 SF	329	if (rc) {
	330	cifs_dbg(VFS, "%s: Could not set key for cmac aes\n", __func__);
	331	return rc;
	332	}
	333
95dc8dd1 SF	334	/*
	335	* we already allocate sdesccmacaes when we init smb3 signing key,
	336	* so unlike smb2 case we do not have to check here if secmech are
	337	* initialized
	338	*/
429b46f4 SF	339	rc = crypto_shash_init(&server->secmech.sdesccmacaes->shash);
	340	if (rc) {
	341	cifs_dbg(VFS, "%s: Could not init cmac aes\n", __func__);
	342	return rc;
	343	}
	344
	345	for (i = 0; i < n_vec; i++) {
	346	if (iov[i].iov_len == 0)
	347	continue;
	348	if (iov[i].iov_base == NULL) {
	349	cifs_dbg(VFS, "null iovec entry");
	350	return -EIO;
	351	}
	352	/*
	353	* The first entry includes a length field (which does not get
	354	* signed that occupies the first 4 bytes before the header).
	355	*/
	356	if (i == 0) {
	357	if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
	358	break; /* nothing to sign or corrupt header */
	359	rc =
	360	crypto_shash_update(
	361	&server->secmech.sdesccmacaes->shash,
	362	iov[i].iov_base + 4, iov[i].iov_len - 4);
	363	} else {
	364	rc =
	365	crypto_shash_update(
	366	&server->secmech.sdesccmacaes->shash,
	367	iov[i].iov_base, iov[i].iov_len);
	368	}
	369	if (rc) {
	370	cifs_dbg(VFS, "%s: Couldn't update cmac aes with payload\n",
	371	__func__);
	372	return rc;
	373	}
	374	}
	375
	376	/* now hash over the rq_pages array */
	377	for (i = 0; i < rqst->rq_npages; i++) {
	378	struct kvec p_iov;
	379
	380	cifs_rqst_page_to_kvec(rqst, i, &p_iov);
	381	crypto_shash_update(&server->secmech.sdesccmacaes->shash,
	382	p_iov.iov_base, p_iov.iov_len);
	383	kunmap(rqst->rq_pages[i]);
	384	}
	385
	386	rc = crypto_shash_final(&server->secmech.sdesccmacaes->shash,
	387	sigptr);
	388	if (rc)
	389	cifs_dbg(VFS, "%s: Could not generate cmac aes\n", __func__);
	390
	391	memcpy(smb2_pdu->Signature, sigptr, SMB2_SIGNATURE_SIZE);
	392
	393	return rc;
38107d45 SF	394	}
38107d45 SF	395
3c1bf7e4 PS	396	/* must be called with server->srv_mutex held */
3c1bf7e4 PS	397	static int
0b688cfc	398	smb2_sign_rqst(struct smb_rqst rqst, struct TCP_Server_Info server)
3c1bf7e4 PS	399	{
3c1bf7e4 PS	400	int rc = 0;
0b688cfc	401	struct smb2_hdr *smb2_pdu = rqst->rq_iov[0].iov_base;
3c1bf7e4 PS	402
	403	if (!(smb2_pdu->Flags & SMB2_FLAGS_SIGNED) \|\|
	404	server->tcpStatus == CifsNeedNegotiate)
	405	return rc;
	406
	407	if (!server->session_estab) {
	408	strncpy(smb2_pdu->Signature, "BSRSPYL", 8);
	409	return rc;
	410	}
	411
38107d45	412	rc = server->ops->calc_signature(rqst, server);
3c1bf7e4 PS	413
	414	return rc;
	415	}
	416
	417	int
0b688cfc	418	smb2_verify_signature(struct smb_rqst rqst, struct TCP_Server_Info server)
3c1bf7e4 PS	419	{
	420	unsigned int rc;
	421	char server_response_sig[16];
0b688cfc	422	struct smb2_hdr smb2_pdu = (struct smb2_hdr )rqst->rq_iov[0].iov_base;
3c1bf7e4 PS	423
3c1bf7e4 PS	424	if ((smb2_pdu->Command == SMB2_NEGOTIATE) \|\|
32811d24	425	(smb2_pdu->Command == SMB2_SESSION_SETUP) \|\|
3c1bf7e4 PS	426	(smb2_pdu->Command == SMB2_OPLOCK_BREAK) \|\|
	427	(!server->session_estab))
	428	return 0;
	429
	430	/*
	431	* BB what if signatures are supposed to be on for session but
	432	* server does not send one? BB
	433	*/
	434
	435	/* Do not need to verify session setups with signature "BSRSPYL " */
	436	if (memcmp(smb2_pdu->Signature, "BSRSPYL ", 8) == 0)
f96637be JP	437	cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
f96637be JP	438	smb2_pdu->Command);
3c1bf7e4 PS	439
	440	/*
	441	* Save off the origiginal signature so we can modify the smb and check
	442	* our calculated signature against what the server sent.
	443	*/
	444	memcpy(server_response_sig, smb2_pdu->Signature, SMB2_SIGNATURE_SIZE);
	445
	446	memset(smb2_pdu->Signature, 0, SMB2_SIGNATURE_SIZE);
	447
	448	mutex_lock(&server->srv_mutex);
38107d45	449	rc = server->ops->calc_signature(rqst, server);
3c1bf7e4 PS	450	mutex_unlock(&server->srv_mutex);
	451
	452	if (rc)
	453	return rc;
	454
	455	if (memcmp(server_response_sig, smb2_pdu->Signature,
	456	SMB2_SIGNATURE_SIZE))
	457	return -EACCES;
	458	else
	459	return 0;
	460	}
	461
2dc7e1c0 PS	462	/*
	463	* Set message id for the request. Should be called after wait_for_free_request
	464	* and when srv_mutex is held.
	465	*/
	466	static inline void
	467	smb2_seq_num_into_buf(struct TCP_Server_Info server, struct smb2_hdr hdr)
	468	{
cb7e9eab PS	469	unsigned int i, num = le16_to_cpu(hdr->CreditCharge);
cb7e9eab PS	470
3d378d3f	471	hdr->MessageId = get_next_mid64(server);
cb7e9eab PS	472	/* skip message numbers according to CreditCharge field */
	473	for (i = 1; i < num; i++)
	474	get_next_mid(server);
2dc7e1c0 PS	475	}
	476
	477	static struct mid_q_entry *
	478	smb2_mid_entry_alloc(const struct smb2_hdr *smb_buffer,
	479	struct TCP_Server_Info *server)
	480	{
	481	struct mid_q_entry *temp;
	482
	483	if (server == NULL) {
f96637be	484	cifs_dbg(VFS, "Null TCP session in smb2_mid_entry_alloc\n");
2dc7e1c0 PS	485	return NULL;
	486	}
	487
	488	temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
	489	if (temp == NULL)
	490	return temp;
	491	else {
	492	memset(temp, 0, sizeof(struct mid_q_entry));
	493	temp->mid = smb_buffer->MessageId; /* always LE */
	494	temp->pid = current->pid;
	495	temp->command = smb_buffer->Command; /* Always LE */
	496	temp->when_alloc = jiffies;
	497	temp->server = server;
	498
	499	/*
	500	* The default is for the mid to be synchronous, so the
	501	* default callback just wakes up the current task.
	502	*/
	503	temp->callback = cifs_wake_up_task;
	504	temp->callback_data = current;
	505	}
	506
	507	atomic_inc(&midCount);
	508	temp->mid_state = MID_REQUEST_ALLOCATED;
	509	return temp;
	510	}
	511
	512	static int
	513	smb2_get_mid_entry(struct cifs_ses ses, struct smb2_hdr buf,
	514	struct mid_q_entry **mid)
	515	{
	516	if (ses->server->tcpStatus == CifsExiting)
	517	return -ENOENT;
	518
	519	if (ses->server->tcpStatus == CifsNeedReconnect) {
f96637be	520	cifs_dbg(FYI, "tcp session dead - return to caller to retry\n");
2dc7e1c0 PS	521	return -EAGAIN;
	522	}
	523
7f48558e	524	if (ses->status == CifsNew) {
2dc7e1c0 PS	525	if ((buf->Command != SMB2_SESSION_SETUP) &&
	526	(buf->Command != SMB2_NEGOTIATE))
	527	return -EAGAIN;
	528	/* else ok - we are setting up session */
	529	}
7f48558e SP	530
	531	if (ses->status == CifsExiting) {
	532	if (buf->Command != SMB2_LOGOFF)
	533	return -EAGAIN;
	534	/* else ok - we are shutting down the session */
	535	}
	536
2dc7e1c0 PS	537	*mid = smb2_mid_entry_alloc(buf, ses->server);
	538	if (*mid == NULL)
	539	return -ENOMEM;
	540	spin_lock(&GlobalMid_Lock);
	541	list_add_tail(&(*mid)->qhead, &ses->server->pending_mid_q);
	542	spin_unlock(&GlobalMid_Lock);
	543	return 0;
	544	}
	545
	546	int
	547	smb2_check_receive(struct mid_q_entry mid, struct TCP_Server_Info server,
	548	bool log_error)
	549	{
	550	unsigned int len = get_rfc1002_length(mid->resp_buf);
0b688cfc JL	551	struct kvec iov;
	552	struct smb_rqst rqst = { .rq_iov = &iov,
	553	.rq_nvec = 1 };
	554
	555	iov.iov_base = (char *)mid->resp_buf;
	556	iov.iov_len = get_rfc1002_length(mid->resp_buf) + 4;
2dc7e1c0 PS	557
	558	dump_smb(mid->resp_buf, min_t(u32, 80, len));
	559	/* convert the length into a more usable form */
38d77c50	560	if (len > 24 && server->sign) {
3c1bf7e4 PS	561	int rc;
3c1bf7e4 PS	562
0b688cfc	563	rc = smb2_verify_signature(&rqst, server);
3c1bf7e4	564	if (rc)
f96637be JP	565	cifs_dbg(VFS, "SMB signature verification returned error = %d\n",
f96637be JP	566	rc);
3c1bf7e4	567	}
2dc7e1c0 PS	568
	569	return map_smb2_to_linux_error(mid->resp_buf, log_error);
	570	}
	571
fec344e3 JL	572	struct mid_q_entry *
fec344e3 JL	573	smb2_setup_request(struct cifs_ses ses, struct smb_rqst rqst)
2dc7e1c0 PS	574	{
2dc7e1c0 PS	575	int rc;
fec344e3	576	struct smb2_hdr hdr = (struct smb2_hdr )rqst->rq_iov[0].iov_base;
2dc7e1c0 PS	577	struct mid_q_entry *mid;
	578
	579	smb2_seq_num_into_buf(ses->server, hdr);
	580
	581	rc = smb2_get_mid_entry(ses, hdr, &mid);
	582	if (rc)
fec344e3 JL	583	return ERR_PTR(rc);
	584	rc = smb2_sign_rqst(rqst, ses->server);
	585	if (rc) {
3c1bf7e4	586	cifs_delete_mid(mid);
fec344e3 JL	587	return ERR_PTR(rc);
	588	}
	589	return mid;
2dc7e1c0 PS	590	}
2dc7e1c0 PS	591
fec344e3 JL	592	struct mid_q_entry *
fec344e3 JL	593	smb2_setup_async_request(struct TCP_Server_Info server, struct smb_rqst rqst)
c95b8eed	594	{
fec344e3 JL	595	int rc;
fec344e3 JL	596	struct smb2_hdr hdr = (struct smb2_hdr )rqst->rq_iov[0].iov_base;
c95b8eed PS	597	struct mid_q_entry *mid;
	598
	599	smb2_seq_num_into_buf(server, hdr);
	600
	601	mid = smb2_mid_entry_alloc(hdr, server);
	602	if (mid == NULL)
fec344e3	603	return ERR_PTR(-ENOMEM);
c95b8eed	604
fec344e3	605	rc = smb2_sign_rqst(rqst, server);
c95b8eed PS	606	if (rc) {
c95b8eed PS	607	DeleteMidQEntry(mid);
fec344e3	608	return ERR_PTR(rc);
3c1bf7e4 PS	609	}
3c1bf7e4 PS	610
fec344e3	611	return mid;
c95b8eed	612	}