Commit | Line | Data |
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1da177e4 LT |
1 | /** |
2 | * BSD Secure Levels LSM | |
3 | * | |
4 | * Maintainers: | |
5 | * Michael A. Halcrow <mike@halcrow.us> | |
6 | * Serge Hallyn <hallyn@cs.wm.edu> | |
7 | * | |
8 | * Copyright (c) 2001 WireX Communications, Inc <chris@wirex.com> | |
9 | * Copyright (c) 2001 Greg Kroah-Hartman <greg@kroah.com> | |
10 | * Copyright (c) 2002 International Business Machines <robb@austin.ibm.com> | |
6bb08da4 | 11 | * Copyright (c) 2006 Davi E. M. Arnaut <davi.arnaut@gmail.com> |
1da177e4 LT |
12 | * |
13 | * This program is free software; you can redistribute it and/or modify | |
14 | * it under the terms of the GNU General Public License as published by | |
15 | * the Free Software Foundation; either version 2 of the License, or | |
16 | * (at your option) any later version. | |
17 | */ | |
18 | ||
1da177e4 LT |
19 | #include <linux/module.h> |
20 | #include <linux/moduleparam.h> | |
21 | #include <linux/kernel.h> | |
22 | #include <linux/init.h> | |
23 | #include <linux/security.h> | |
24 | #include <linux/netlink.h> | |
25 | #include <linux/fs.h> | |
26 | #include <linux/namei.h> | |
27 | #include <linux/mount.h> | |
28 | #include <linux/capability.h> | |
29 | #include <linux/time.h> | |
30 | #include <linux/proc_fs.h> | |
31 | #include <linux/kobject.h> | |
32 | #include <linux/crypto.h> | |
33 | #include <asm/scatterlist.h> | |
6bb08da4 | 34 | #include <linux/scatterlist.h> |
1da177e4 LT |
35 | #include <linux/gfp.h> |
36 | #include <linux/sysfs.h> | |
37 | ||
38 | #define SHA1_DIGEST_SIZE 20 | |
39 | ||
40 | /** | |
41 | * Module parameter that defines the initial secure level. | |
42 | * | |
43 | * When built as a module, it defaults to seclvl 1, which is the | |
44 | * behavior of BSD secure levels. Note that this default behavior | |
45 | * wrecks havoc on a machine when the seclvl module is compiled into | |
46 | * the kernel. In that case, we default to seclvl 0. | |
47 | */ | |
48 | #ifdef CONFIG_SECURITY_SECLVL_MODULE | |
49 | static int initlvl = 1; | |
50 | #else | |
51 | static int initlvl; | |
52 | #endif | |
53 | module_param(initlvl, int, 0); | |
54 | MODULE_PARM_DESC(initlvl, "Initial secure level (defaults to 1)"); | |
55 | ||
56 | /* Module parameter that defines the verbosity level */ | |
57 | static int verbosity; | |
58 | module_param(verbosity, int, 0); | |
59 | MODULE_PARM_DESC(verbosity, "Initial verbosity level (0 or 1; defaults to " | |
60 | "0, which is Quiet)"); | |
61 | ||
62 | /** | |
63 | * Optional password which can be passed in to bring seclvl to 0 | |
64 | * (i.e., for halt/reboot). Defaults to NULL (the passwd attribute | |
65 | * file will not be registered in sysfs). | |
66 | * | |
67 | * This gets converted to its SHA1 hash when stored. It's probably | |
68 | * not a good idea to use this parameter when loading seclvl from a | |
69 | * script; use sha1_passwd instead. | |
70 | */ | |
71 | ||
72 | #define MAX_PASSWD_SIZE 32 | |
73 | static char passwd[MAX_PASSWD_SIZE]; | |
74 | module_param_string(passwd, passwd, sizeof(passwd), 0); | |
75 | MODULE_PARM_DESC(passwd, | |
76 | "Plaintext of password that sets seclvl=0 when written to " | |
77 | "(sysfs mount point)/seclvl/passwd\n"); | |
78 | ||
79 | /** | |
80 | * SHA1 hashed version of the optional password which can be passed in | |
81 | * to bring seclvl to 0 (i.e., for halt/reboot). Must be in | |
82 | * hexadecimal format (40 characters). Defaults to NULL (the passwd | |
83 | * attribute file will not be registered in sysfs). | |
84 | * | |
85 | * Use the sha1sum utility to generate the SHA1 hash of a password: | |
86 | * | |
87 | * echo -n "secret" | sha1sum | |
88 | */ | |
89 | #define MAX_SHA1_PASSWD 41 | |
90 | static char sha1_passwd[MAX_SHA1_PASSWD]; | |
91 | module_param_string(sha1_passwd, sha1_passwd, sizeof(sha1_passwd), 0); | |
92 | MODULE_PARM_DESC(sha1_passwd, | |
93 | "SHA1 hash (40 hexadecimal characters) of password that " | |
94 | "sets seclvl=0 when plaintext password is written to " | |
95 | "(sysfs mount point)/seclvl/passwd\n"); | |
96 | ||
97 | static int hideHash = 1; | |
98 | module_param(hideHash, int, 0); | |
99 | MODULE_PARM_DESC(hideHash, "When set to 0, reading seclvl/passwd from sysfs " | |
100 | "will return the SHA1-hashed value of the password that " | |
101 | "lowers the secure level to 0.\n"); | |
102 | ||
103 | #define MY_NAME "seclvl" | |
104 | ||
105 | /** | |
106 | * This time-limits log writes to one per second. | |
107 | */ | |
108 | #define seclvl_printk(verb, type, fmt, arg...) \ | |
109 | do { \ | |
110 | if (verbosity >= verb) { \ | |
111 | static unsigned long _prior; \ | |
112 | unsigned long _now = jiffies; \ | |
113 | if ((_now - _prior) > HZ) { \ | |
114 | printk(type "%s: %s: " fmt, \ | |
115 | MY_NAME, __FUNCTION__ , \ | |
116 | ## arg); \ | |
117 | _prior = _now; \ | |
118 | } \ | |
119 | } \ | |
120 | } while (0) | |
121 | ||
1da177e4 LT |
122 | /** |
123 | * The actual security level. Ranges between -1 and 2 inclusive. | |
124 | */ | |
125 | static int seclvl; | |
126 | ||
127 | /** | |
128 | * flag to keep track of how we were registered | |
129 | */ | |
130 | static int secondary; | |
131 | ||
132 | /** | |
133 | * Verifies that the requested secure level is valid, given the current | |
134 | * secure level. | |
135 | */ | |
136 | static int seclvl_sanity(int reqlvl) | |
137 | { | |
138 | if ((reqlvl < -1) || (reqlvl > 2)) { | |
139 | seclvl_printk(1, KERN_WARNING, "Attempt to set seclvl out of " | |
140 | "range: [%d]\n", reqlvl); | |
141 | return -EINVAL; | |
142 | } | |
143 | if ((seclvl == 0) && (reqlvl == -1)) | |
144 | return 0; | |
145 | if (reqlvl < seclvl) { | |
146 | seclvl_printk(1, KERN_WARNING, "Attempt to lower seclvl to " | |
147 | "[%d]\n", reqlvl); | |
148 | return -EPERM; | |
149 | } | |
150 | return 0; | |
151 | } | |
152 | ||
1da177e4 LT |
153 | /** |
154 | * security level advancement rules: | |
155 | * Valid levels are -1 through 2, inclusive. | |
156 | * From -1, stuck. [ in case compiled into kernel ] | |
157 | * From 0 or above, can only increment. | |
158 | */ | |
5a73c308 | 159 | static void do_seclvl_advance(void *data, u64 val) |
1da177e4 | 160 | { |
5a73c308 | 161 | int ret; |
162 | int newlvl = (int)val; | |
163 | ||
164 | ret = seclvl_sanity(newlvl); | |
165 | if (ret) | |
166 | return; | |
167 | ||
1da177e4 LT |
168 | if (newlvl > 2) { |
169 | seclvl_printk(1, KERN_WARNING, "Cannot advance to seclvl " | |
170 | "[%d]\n", newlvl); | |
5a73c308 | 171 | return; |
1da177e4 LT |
172 | } |
173 | if (seclvl == -1) { | |
174 | seclvl_printk(1, KERN_WARNING, "Not allowed to advance to " | |
175 | "seclvl [%d]\n", seclvl); | |
5a73c308 | 176 | return; |
1da177e4 | 177 | } |
5a73c308 | 178 | seclvl = newlvl; /* would it be more "correct" to set *data? */ |
179 | return; | |
1da177e4 LT |
180 | } |
181 | ||
5a73c308 | 182 | static u64 seclvl_int_get(void *data) |
1da177e4 | 183 | { |
5a73c308 | 184 | return *(int *)data; |
1da177e4 LT |
185 | } |
186 | ||
5a73c308 | 187 | DEFINE_SIMPLE_ATTRIBUTE(seclvl_file_ops, seclvl_int_get, do_seclvl_advance, "%lld\n"); |
1da177e4 LT |
188 | |
189 | static unsigned char hashedPassword[SHA1_DIGEST_SIZE]; | |
190 | ||
1da177e4 LT |
191 | /** |
192 | * Converts a block of plaintext of into its SHA1 hashed value. | |
193 | * | |
194 | * It would be nice if crypto had a wrapper to do this for us linear | |
195 | * people... | |
196 | */ | |
197 | static int | |
6bb08da4 | 198 | plaintext_to_sha1(unsigned char *hash, const char *plaintext, unsigned int len) |
1da177e4 | 199 | { |
1da177e4 | 200 | struct crypto_tfm *tfm; |
6bb08da4 | 201 | struct scatterlist sg; |
1da177e4 LT |
202 | if (len > PAGE_SIZE) { |
203 | seclvl_printk(0, KERN_ERR, "Plaintext password too large (%d " | |
204 | "characters). Largest possible is %lu " | |
205 | "bytes.\n", len, PAGE_SIZE); | |
6bb08da4 | 206 | return -EINVAL; |
1da177e4 | 207 | } |
eb6f1160 | 208 | tfm = crypto_alloc_tfm("sha1", CRYPTO_TFM_REQ_MAY_SLEEP); |
1da177e4 LT |
209 | if (tfm == NULL) { |
210 | seclvl_printk(0, KERN_ERR, | |
211 | "Failed to load transform for SHA1\n"); | |
6bb08da4 | 212 | return -EINVAL; |
1da177e4 | 213 | } |
6bb08da4 | 214 | sg_init_one(&sg, (u8 *)plaintext, len); |
1da177e4 | 215 | crypto_digest_init(tfm); |
6bb08da4 | 216 | crypto_digest_update(tfm, &sg, 1); |
1da177e4 LT |
217 | crypto_digest_final(tfm, hash); |
218 | crypto_free_tfm(tfm); | |
1da177e4 LT |
219 | return 0; |
220 | } | |
221 | ||
222 | /** | |
223 | * Called whenever the user writes to the sysfs passwd handle to this kernel | |
224 | * object. It hashes the password and compares the hashed results. | |
225 | */ | |
226 | static ssize_t | |
5a73c308 | 227 | passwd_write_file(struct file * file, const char __user * buf, |
228 | size_t count, loff_t *ppos) | |
1da177e4 | 229 | { |
6bb08da4 | 230 | char *p; |
1da177e4 | 231 | int len; |
6bb08da4 | 232 | unsigned char tmp[SHA1_DIGEST_SIZE]; |
5a73c308 | 233 | |
1da177e4 LT |
234 | if (!*passwd && !*sha1_passwd) { |
235 | seclvl_printk(0, KERN_ERR, "Attempt to password-unlock the " | |
236 | "seclvl module, but neither a plain text " | |
237 | "password nor a SHA1 hashed password was " | |
238 | "passed in as a module parameter! This is a " | |
239 | "bug, since it should not be possible to be in " | |
240 | "this part of the module; please tell a " | |
241 | "maintainer about this event.\n"); | |
242 | return -EINVAL; | |
243 | } | |
5a73c308 | 244 | |
6bb08da4 | 245 | if (count >= PAGE_SIZE) |
9afa57b0 | 246 | return -EINVAL; |
d15c5749 | 247 | if (*ppos != 0) |
5a73c308 | 248 | return -EINVAL; |
6bb08da4 DA |
249 | p = kmalloc(count, GFP_KERNEL); |
250 | if (!p) | |
5a73c308 | 251 | return -ENOMEM; |
252 | len = -EFAULT; | |
6bb08da4 | 253 | if (copy_from_user(p, buf, count)) |
5a73c308 | 254 | goto out; |
255 | ||
6bb08da4 | 256 | len = count; |
1da177e4 | 257 | /* ``echo "secret" > seclvl/passwd'' includes a newline */ |
6bb08da4 | 258 | if (p[len - 1] == '\n') |
1da177e4 | 259 | len--; |
1da177e4 | 260 | /* Hash the password, then compare the hashed values */ |
6bb08da4 | 261 | if ((len = plaintext_to_sha1(tmp, p, len))) { |
1da177e4 | 262 | seclvl_printk(0, KERN_ERR, "Error hashing password: rc = " |
6bb08da4 DA |
263 | "[%d]\n", len); |
264 | goto out; | |
1da177e4 | 265 | } |
6bb08da4 DA |
266 | |
267 | len = -EPERM; | |
268 | if (memcmp(hashedPassword, tmp, SHA1_DIGEST_SIZE)) | |
269 | goto out; | |
270 | ||
1da177e4 LT |
271 | seclvl_printk(0, KERN_INFO, |
272 | "Password accepted; seclvl reduced to 0.\n"); | |
273 | seclvl = 0; | |
5a73c308 | 274 | len = count; |
275 | ||
276 | out: | |
6bb08da4 | 277 | kfree (p); |
5a73c308 | 278 | return len; |
1da177e4 LT |
279 | } |
280 | ||
5a73c308 | 281 | static struct file_operations passwd_file_ops = { |
282 | .write = passwd_write_file, | |
283 | }; | |
1da177e4 LT |
284 | |
285 | /** | |
286 | * Explicitely disallow ptrace'ing the init process. | |
287 | */ | |
288 | static int seclvl_ptrace(struct task_struct *parent, struct task_struct *child) | |
289 | { | |
6bb08da4 DA |
290 | if (seclvl >= 0 && child->pid == 1) { |
291 | seclvl_printk(1, KERN_WARNING, "Attempt to ptrace " | |
292 | "the init process dissallowed in " | |
293 | "secure level %d\n", seclvl); | |
294 | return -EPERM; | |
1da177e4 LT |
295 | } |
296 | return 0; | |
297 | } | |
298 | ||
299 | /** | |
300 | * Capability checks for seclvl. The majority of the policy | |
301 | * enforcement for seclvl takes place here. | |
302 | */ | |
303 | static int seclvl_capable(struct task_struct *tsk, int cap) | |
304 | { | |
6bb08da4 DA |
305 | int rc = 0; |
306 | ||
1da177e4 LT |
307 | /* init can do anything it wants */ |
308 | if (tsk->pid == 1) | |
309 | return 0; | |
310 | ||
6bb08da4 DA |
311 | if (seclvl > 0) { |
312 | rc = -EPERM; | |
313 | ||
314 | if (cap == CAP_LINUX_IMMUTABLE) | |
1da177e4 LT |
315 | seclvl_printk(1, KERN_WARNING, "Attempt to modify " |
316 | "the IMMUTABLE and/or APPEND extended " | |
317 | "attribute on a file with the IMMUTABLE " | |
318 | "and/or APPEND extended attribute set " | |
319 | "denied in seclvl [%d]\n", seclvl); | |
6bb08da4 | 320 | else if (cap == CAP_SYS_RAWIO) |
1da177e4 LT |
321 | seclvl_printk(1, KERN_WARNING, "Attempt to perform " |
322 | "raw I/O while in secure level [%d] " | |
323 | "denied\n", seclvl); | |
6bb08da4 | 324 | else if (cap == CAP_NET_ADMIN) |
1da177e4 LT |
325 | seclvl_printk(1, KERN_WARNING, "Attempt to perform " |
326 | "network administrative task while " | |
327 | "in secure level [%d] denied\n", seclvl); | |
6bb08da4 | 328 | else if (cap == CAP_SETUID) |
1da177e4 LT |
329 | seclvl_printk(1, KERN_WARNING, "Attempt to setuid " |
330 | "while in secure level [%d] denied\n", | |
331 | seclvl); | |
6bb08da4 | 332 | else if (cap == CAP_SETGID) |
1da177e4 LT |
333 | seclvl_printk(1, KERN_WARNING, "Attempt to setgid " |
334 | "while in secure level [%d] denied\n", | |
335 | seclvl); | |
6bb08da4 | 336 | else if (cap == CAP_SYS_MODULE) |
1da177e4 LT |
337 | seclvl_printk(1, KERN_WARNING, "Attempt to perform " |
338 | "a module operation while in secure " | |
339 | "level [%d] denied\n", seclvl); | |
6bb08da4 DA |
340 | else |
341 | rc = 0; | |
1da177e4 | 342 | } |
6bb08da4 DA |
343 | |
344 | if (!rc) { | |
345 | if (!(cap_is_fs_cap(cap) ? tsk->fsuid == 0 : tsk->euid == 0)) | |
346 | rc = -EPERM; | |
347 | } | |
348 | ||
349 | if (rc) | |
350 | seclvl_printk(1, KERN_WARNING, "Capability denied\n"); | |
351 | ||
352 | return rc; | |
1da177e4 LT |
353 | } |
354 | ||
355 | /** | |
356 | * Disallow reversing the clock in seclvl > 1 | |
357 | */ | |
358 | static int seclvl_settime(struct timespec *tv, struct timezone *tz) | |
359 | { | |
951069e3 LT |
360 | if (tv && seclvl > 1) { |
361 | struct timespec now; | |
1da177e4 LT |
362 | now = current_kernel_time(); |
363 | if (tv->tv_sec < now.tv_sec || | |
364 | (tv->tv_sec == now.tv_sec && tv->tv_nsec < now.tv_nsec)) { | |
365 | seclvl_printk(1, KERN_WARNING, "Attempt to decrement " | |
366 | "time in secure level %d denied: " | |
367 | "current->pid = [%d], " | |
368 | "current->group_leader->pid = [%d]\n", | |
369 | seclvl, current->pid, | |
370 | current->group_leader->pid); | |
371 | return -EPERM; | |
372 | } /* if attempt to decrement time */ | |
373 | } /* if seclvl > 1 */ | |
374 | return 0; | |
375 | } | |
376 | ||
377 | /* claim the blockdev to exclude mounters, release on file close */ | |
378 | static int seclvl_bd_claim(struct inode *inode) | |
379 | { | |
380 | int holder; | |
381 | struct block_device *bdev = NULL; | |
382 | dev_t dev = inode->i_rdev; | |
383 | bdev = open_by_devnum(dev, FMODE_WRITE); | |
384 | if (bdev) { | |
385 | if (bd_claim(bdev, &holder)) { | |
386 | blkdev_put(bdev); | |
387 | return -EPERM; | |
388 | } | |
389 | /* claimed, mark it to release on close */ | |
390 | inode->i_security = current; | |
391 | } | |
392 | return 0; | |
393 | } | |
394 | ||
395 | /* release the blockdev if you claimed it */ | |
396 | static void seclvl_bd_release(struct inode *inode) | |
397 | { | |
398 | if (inode && S_ISBLK(inode->i_mode) && inode->i_security == current) { | |
399 | struct block_device *bdev = inode->i_bdev; | |
400 | if (bdev) { | |
401 | bd_release(bdev); | |
402 | blkdev_put(bdev); | |
403 | inode->i_security = NULL; | |
404 | } | |
405 | } | |
406 | } | |
407 | ||
408 | /** | |
409 | * Security for writes to block devices is regulated by this seclvl | |
410 | * function. Deny all writes to block devices in seclvl 2. In | |
411 | * seclvl 1, we only deny writes to *mounted* block devices. | |
412 | */ | |
413 | static int | |
414 | seclvl_inode_permission(struct inode *inode, int mask, struct nameidata *nd) | |
415 | { | |
416 | if (current->pid != 1 && S_ISBLK(inode->i_mode) && (mask & MAY_WRITE)) { | |
417 | switch (seclvl) { | |
418 | case 2: | |
419 | seclvl_printk(1, KERN_WARNING, "Write to block device " | |
420 | "denied in secure level [%d]\n", seclvl); | |
421 | return -EPERM; | |
422 | case 1: | |
423 | if (seclvl_bd_claim(inode)) { | |
424 | seclvl_printk(1, KERN_WARNING, | |
425 | "Write to mounted block device " | |
426 | "denied in secure level [%d]\n", | |
427 | seclvl); | |
428 | return -EPERM; | |
429 | } | |
430 | } | |
431 | } | |
432 | return 0; | |
433 | } | |
434 | ||
435 | /** | |
436 | * The SUID and SGID bits cannot be set in seclvl >= 1 | |
437 | */ | |
438 | static int seclvl_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
439 | { | |
440 | if (seclvl > 0) { | |
441 | if (iattr->ia_valid & ATTR_MODE) | |
442 | if (iattr->ia_mode & S_ISUID || | |
443 | iattr->ia_mode & S_ISGID) { | |
444 | seclvl_printk(1, KERN_WARNING, "Attempt to " | |
445 | "modify SUID or SGID bit " | |
446 | "denied in seclvl [%d]\n", | |
447 | seclvl); | |
448 | return -EPERM; | |
449 | } | |
450 | } | |
451 | return 0; | |
452 | } | |
453 | ||
454 | /* release busied block devices */ | |
455 | static void seclvl_file_free_security(struct file *filp) | |
456 | { | |
457 | struct dentry *dentry = filp->f_dentry; | |
1da177e4 | 458 | |
6bb08da4 DA |
459 | if (dentry) |
460 | seclvl_bd_release(dentry->d_inode); | |
1da177e4 LT |
461 | } |
462 | ||
463 | /** | |
464 | * Cannot unmount in secure level 2 | |
465 | */ | |
466 | static int seclvl_umount(struct vfsmount *mnt, int flags) | |
467 | { | |
6bb08da4 | 468 | if (current->pid != 1 && seclvl == 2) { |
1da177e4 LT |
469 | seclvl_printk(1, KERN_WARNING, "Attempt to unmount in secure " |
470 | "level %d\n", seclvl); | |
471 | return -EPERM; | |
472 | } | |
473 | return 0; | |
474 | } | |
475 | ||
476 | static struct security_operations seclvl_ops = { | |
477 | .ptrace = seclvl_ptrace, | |
478 | .capable = seclvl_capable, | |
479 | .inode_permission = seclvl_inode_permission, | |
480 | .inode_setattr = seclvl_inode_setattr, | |
481 | .file_free_security = seclvl_file_free_security, | |
482 | .settime = seclvl_settime, | |
483 | .sb_umount = seclvl_umount, | |
484 | }; | |
485 | ||
486 | /** | |
487 | * Process the password-related module parameters | |
488 | */ | |
489 | static int processPassword(void) | |
490 | { | |
491 | int rc = 0; | |
1da177e4 | 492 | if (*passwd) { |
6bb08da4 DA |
493 | char *p; |
494 | ||
1da177e4 LT |
495 | if (*sha1_passwd) { |
496 | seclvl_printk(0, KERN_ERR, "Error: Both " | |
497 | "passwd and sha1_passwd " | |
498 | "were set, but they are mutually " | |
499 | "exclusive.\n"); | |
500 | return -EINVAL; | |
501 | } | |
6bb08da4 DA |
502 | |
503 | p = kstrdup(passwd, GFP_KERNEL); | |
504 | if (p == NULL) | |
505 | return -ENOMEM; | |
506 | ||
507 | if ((rc = plaintext_to_sha1(hashedPassword, p, strlen(p)))) | |
1da177e4 LT |
508 | seclvl_printk(0, KERN_ERR, "Error: SHA1 support not " |
509 | "in kernel\n"); | |
6bb08da4 DA |
510 | |
511 | kfree (p); | |
1da177e4 LT |
512 | /* All static data goes to the BSS, which zero's the |
513 | * plaintext password out for us. */ | |
514 | } else if (*sha1_passwd) { // Base 16 | |
515 | int i; | |
516 | i = strlen(sha1_passwd); | |
517 | if (i != (SHA1_DIGEST_SIZE * 2)) { | |
518 | seclvl_printk(0, KERN_ERR, "Received [%d] bytes; " | |
519 | "expected [%d] for the hexadecimal " | |
520 | "representation of the SHA1 hash of " | |
521 | "the password.\n", | |
522 | i, (SHA1_DIGEST_SIZE * 2)); | |
523 | return -EINVAL; | |
524 | } | |
525 | while ((i -= 2) + 2) { | |
526 | unsigned char tmp; | |
527 | tmp = sha1_passwd[i + 2]; | |
528 | sha1_passwd[i + 2] = '\0'; | |
529 | hashedPassword[i / 2] = (unsigned char) | |
530 | simple_strtol(&sha1_passwd[i], NULL, 16); | |
531 | sha1_passwd[i + 2] = tmp; | |
532 | } | |
533 | } | |
6bb08da4 | 534 | return rc; |
1da177e4 LT |
535 | } |
536 | ||
537 | /** | |
5a73c308 | 538 | * securityfs registrations |
1da177e4 | 539 | */ |
5a73c308 | 540 | struct dentry *dir_ino, *seclvl_ino, *passwd_ino; |
541 | ||
542 | static int seclvlfs_register(void) | |
1da177e4 | 543 | { |
6bb08da4 DA |
544 | int rc = 0; |
545 | ||
5a73c308 | 546 | dir_ino = securityfs_create_dir("seclvl", NULL); |
6bb08da4 DA |
547 | |
548 | if (IS_ERR(dir_ino)) | |
549 | return PTR_ERR(dir_ino); | |
5a73c308 | 550 | |
551 | seclvl_ino = securityfs_create_file("seclvl", S_IRUGO | S_IWUSR, | |
552 | dir_ino, &seclvl, &seclvl_file_ops); | |
6bb08da4 DA |
553 | if (IS_ERR(seclvl_ino)) { |
554 | rc = PTR_ERR(seclvl_ino); | |
5a73c308 | 555 | goto out_deldir; |
6bb08da4 | 556 | } |
1da177e4 | 557 | if (*passwd || *sha1_passwd) { |
5a73c308 | 558 | passwd_ino = securityfs_create_file("passwd", S_IRUGO | S_IWUSR, |
559 | dir_ino, NULL, &passwd_file_ops); | |
6bb08da4 DA |
560 | if (IS_ERR(passwd_ino)) { |
561 | rc = PTR_ERR(passwd_ino); | |
5a73c308 | 562 | goto out_delf; |
6bb08da4 | 563 | } |
1da177e4 | 564 | } |
6bb08da4 DA |
565 | return rc; |
566 | ||
567 | out_delf: | |
568 | securityfs_remove(seclvl_ino); | |
5a73c308 | 569 | |
570 | out_deldir: | |
571 | securityfs_remove(dir_ino); | |
6bb08da4 DA |
572 | |
573 | return rc; | |
574 | } | |
575 | ||
576 | static void seclvlfs_unregister(void) | |
577 | { | |
5a73c308 | 578 | securityfs_remove(seclvl_ino); |
579 | ||
6bb08da4 DA |
580 | if (*passwd || *sha1_passwd) |
581 | securityfs_remove(passwd_ino); | |
582 | ||
583 | securityfs_remove(dir_ino); | |
1da177e4 LT |
584 | } |
585 | ||
586 | /** | |
587 | * Initialize the seclvl module. | |
588 | */ | |
589 | static int __init seclvl_init(void) | |
590 | { | |
591 | int rc = 0; | |
6bb08da4 DA |
592 | static char once; |
593 | ||
1da177e4 LT |
594 | if (verbosity < 0 || verbosity > 1) { |
595 | printk(KERN_ERR "Error: bad verbosity [%d]; only 0 or 1 " | |
596 | "are valid values\n", verbosity); | |
597 | rc = -EINVAL; | |
598 | goto exit; | |
599 | } | |
1da177e4 LT |
600 | if (initlvl < -1 || initlvl > 2) { |
601 | seclvl_printk(0, KERN_ERR, "Error: bad initial securelevel " | |
602 | "[%d].\n", initlvl); | |
603 | rc = -EINVAL; | |
604 | goto exit; | |
605 | } | |
606 | seclvl = initlvl; | |
607 | if ((rc = processPassword())) { | |
608 | seclvl_printk(0, KERN_ERR, "Error processing the password " | |
609 | "module parameter(s): rc = [%d]\n", rc); | |
610 | goto exit; | |
611 | } | |
6bb08da4 DA |
612 | |
613 | if ((rc = seclvlfs_register())) { | |
614 | seclvl_printk(0, KERN_ERR, "Error registering with sysfs\n"); | |
615 | goto exit; | |
616 | } | |
1da177e4 LT |
617 | /* register ourselves with the security framework */ |
618 | if (register_security(&seclvl_ops)) { | |
619 | seclvl_printk(0, KERN_ERR, | |
620 | "seclvl: Failure registering with the " | |
621 | "kernel.\n"); | |
622 | /* try registering with primary module */ | |
623 | rc = mod_reg_security(MY_NAME, &seclvl_ops); | |
624 | if (rc) { | |
625 | seclvl_printk(0, KERN_ERR, "seclvl: Failure " | |
626 | "registering with primary security " | |
627 | "module.\n"); | |
6bb08da4 | 628 | seclvlfs_unregister(); |
1da177e4 LT |
629 | goto exit; |
630 | } /* if primary module registered */ | |
631 | secondary = 1; | |
632 | } /* if we registered ourselves with the security framework */ | |
6bb08da4 | 633 | |
1da177e4 | 634 | seclvl_printk(0, KERN_INFO, "seclvl: Successfully initialized.\n"); |
6bb08da4 DA |
635 | |
636 | if (once) { | |
637 | once = 1; | |
638 | seclvl_printk(0, KERN_INFO, "seclvl is going away. It has been " | |
639 | "buggy for ages. Also, be warned that " | |
640 | "Securelevels are useless."); | |
641 | } | |
1da177e4 | 642 | exit: |
6bb08da4 | 643 | if (rc) |
1da177e4 LT |
644 | printk(KERN_ERR "seclvl: Error during initialization: rc = " |
645 | "[%d]\n", rc); | |
1da177e4 LT |
646 | return rc; |
647 | } | |
648 | ||
649 | /** | |
650 | * Remove the seclvl module. | |
651 | */ | |
652 | static void __exit seclvl_exit(void) | |
653 | { | |
6bb08da4 DA |
654 | seclvlfs_unregister(); |
655 | ||
656 | if (secondary) | |
1da177e4 | 657 | mod_unreg_security(MY_NAME, &seclvl_ops); |
6bb08da4 | 658 | else if (unregister_security(&seclvl_ops)) |
1da177e4 LT |
659 | seclvl_printk(0, KERN_INFO, |
660 | "seclvl: Failure unregistering with the " | |
661 | "kernel\n"); | |
1da177e4 LT |
662 | } |
663 | ||
664 | module_init(seclvl_init); | |
665 | module_exit(seclvl_exit); | |
666 | ||
667 | MODULE_AUTHOR("Michael A. Halcrow <mike@halcrow.us>"); | |
668 | MODULE_DESCRIPTION("LSM implementation of the BSD Secure Levels"); | |
669 | MODULE_LICENSE("GPL"); |