Commit | Line | Data |
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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
eadd99cc TH |
2 | /* |
3 | * security/tomoyo/audit.c | |
4 | * | |
0f2a55d5 | 5 | * Copyright (C) 2005-2011 NTT DATA CORPORATION |
eadd99cc TH |
6 | */ |
7 | ||
8 | #include "common.h" | |
9 | #include <linux/slab.h> | |
10 | ||
5b636857 TH |
11 | /** |
12 | * tomoyo_print_bprm - Print "struct linux_binprm" for auditing. | |
13 | * | |
14 | * @bprm: Pointer to "struct linux_binprm". | |
15 | * @dump: Pointer to "struct tomoyo_page_dump". | |
16 | * | |
17 | * Returns the contents of @bprm on success, NULL otherwise. | |
18 | * | |
19 | * This function uses kzalloc(), so caller must kfree() if this function | |
20 | * didn't return NULL. | |
21 | */ | |
22 | static char *tomoyo_print_bprm(struct linux_binprm *bprm, | |
23 | struct tomoyo_page_dump *dump) | |
24 | { | |
25 | static const int tomoyo_buffer_len = 4096 * 2; | |
26 | char *buffer = kzalloc(tomoyo_buffer_len, GFP_NOFS); | |
27 | char *cp; | |
28 | char *last_start; | |
29 | int len; | |
30 | unsigned long pos = bprm->p; | |
31 | int offset = pos % PAGE_SIZE; | |
32 | int argv_count = bprm->argc; | |
33 | int envp_count = bprm->envc; | |
34 | bool truncated = false; | |
cdcf6723 | 35 | |
5b636857 TH |
36 | if (!buffer) |
37 | return NULL; | |
38 | len = snprintf(buffer, tomoyo_buffer_len - 1, "argv[]={ "); | |
39 | cp = buffer + len; | |
40 | if (!argv_count) { | |
41 | memmove(cp, "} envp[]={ ", 11); | |
42 | cp += 11; | |
43 | } | |
44 | last_start = cp; | |
45 | while (argv_count || envp_count) { | |
46 | if (!tomoyo_dump_page(bprm, pos, dump)) | |
47 | goto out; | |
48 | pos += PAGE_SIZE - offset; | |
49 | /* Read. */ | |
50 | while (offset < PAGE_SIZE) { | |
51 | const char *kaddr = dump->data; | |
52 | const unsigned char c = kaddr[offset++]; | |
cdcf6723 | 53 | |
5b636857 TH |
54 | if (cp == last_start) |
55 | *cp++ = '"'; | |
56 | if (cp >= buffer + tomoyo_buffer_len - 32) { | |
57 | /* Reserve some room for "..." string. */ | |
58 | truncated = true; | |
59 | } else if (c == '\\') { | |
60 | *cp++ = '\\'; | |
61 | *cp++ = '\\'; | |
62 | } else if (c > ' ' && c < 127) { | |
63 | *cp++ = c; | |
64 | } else if (!c) { | |
65 | *cp++ = '"'; | |
66 | *cp++ = ' '; | |
67 | last_start = cp; | |
68 | } else { | |
69 | *cp++ = '\\'; | |
70 | *cp++ = (c >> 6) + '0'; | |
71 | *cp++ = ((c >> 3) & 7) + '0'; | |
72 | *cp++ = (c & 7) + '0'; | |
73 | } | |
74 | if (c) | |
75 | continue; | |
76 | if (argv_count) { | |
77 | if (--argv_count == 0) { | |
78 | if (truncated) { | |
79 | cp = last_start; | |
80 | memmove(cp, "... ", 4); | |
81 | cp += 4; | |
82 | } | |
83 | memmove(cp, "} envp[]={ ", 11); | |
84 | cp += 11; | |
85 | last_start = cp; | |
86 | truncated = false; | |
87 | } | |
88 | } else if (envp_count) { | |
89 | if (--envp_count == 0) { | |
90 | if (truncated) { | |
91 | cp = last_start; | |
92 | memmove(cp, "... ", 4); | |
93 | cp += 4; | |
94 | } | |
95 | } | |
96 | } | |
97 | if (!argv_count && !envp_count) | |
98 | break; | |
99 | } | |
100 | offset = 0; | |
101 | } | |
102 | *cp++ = '}'; | |
103 | *cp = '\0'; | |
104 | return buffer; | |
105 | out: | |
106 | snprintf(buffer, tomoyo_buffer_len - 1, | |
107 | "argv[]={ ... } envp[]= { ... }"); | |
108 | return buffer; | |
109 | } | |
110 | ||
8761afd4 TH |
111 | /** |
112 | * tomoyo_filetype - Get string representation of file type. | |
113 | * | |
114 | * @mode: Mode value for stat(). | |
115 | * | |
116 | * Returns file type string. | |
117 | */ | |
d179333f | 118 | static inline const char *tomoyo_filetype(const umode_t mode) |
8761afd4 TH |
119 | { |
120 | switch (mode & S_IFMT) { | |
121 | case S_IFREG: | |
122 | case 0: | |
123 | return tomoyo_condition_keyword[TOMOYO_TYPE_IS_FILE]; | |
124 | case S_IFDIR: | |
125 | return tomoyo_condition_keyword[TOMOYO_TYPE_IS_DIRECTORY]; | |
126 | case S_IFLNK: | |
127 | return tomoyo_condition_keyword[TOMOYO_TYPE_IS_SYMLINK]; | |
128 | case S_IFIFO: | |
129 | return tomoyo_condition_keyword[TOMOYO_TYPE_IS_FIFO]; | |
130 | case S_IFSOCK: | |
131 | return tomoyo_condition_keyword[TOMOYO_TYPE_IS_SOCKET]; | |
132 | case S_IFBLK: | |
133 | return tomoyo_condition_keyword[TOMOYO_TYPE_IS_BLOCK_DEV]; | |
134 | case S_IFCHR: | |
135 | return tomoyo_condition_keyword[TOMOYO_TYPE_IS_CHAR_DEV]; | |
136 | } | |
137 | return "unknown"; /* This should not happen. */ | |
138 | } | |
139 | ||
eadd99cc TH |
140 | /** |
141 | * tomoyo_print_header - Get header line of audit log. | |
142 | * | |
143 | * @r: Pointer to "struct tomoyo_request_info". | |
144 | * | |
145 | * Returns string representation. | |
146 | * | |
147 | * This function uses kmalloc(), so caller must kfree() if this function | |
148 | * didn't return NULL. | |
149 | */ | |
150 | static char *tomoyo_print_header(struct tomoyo_request_info *r) | |
151 | { | |
152 | struct tomoyo_time stamp; | |
153 | const pid_t gpid = task_pid_nr(current); | |
8761afd4 | 154 | struct tomoyo_obj_info *obj = r->obj; |
eadd99cc TH |
155 | static const int tomoyo_buffer_len = 4096; |
156 | char *buffer = kmalloc(tomoyo_buffer_len, GFP_NOFS); | |
2066a361 | 157 | int pos; |
8761afd4 | 158 | u8 i; |
cdcf6723 | 159 | |
eadd99cc TH |
160 | if (!buffer) |
161 | return NULL; | |
77f4fa08 | 162 | |
92734092 | 163 | tomoyo_convert_time(ktime_get_real_seconds(), &stamp); |
77f4fa08 | 164 | |
2066a361 | 165 | pos = snprintf(buffer, tomoyo_buffer_len - 1, |
cdcf6723 TH |
166 | "#%04u/%02u/%02u %02u:%02u:%02u# profile=%u mode=%s granted=%s (global-pid=%u) task={ pid=%u ppid=%u uid=%u gid=%u euid=%u egid=%u suid=%u sgid=%u fsuid=%u fsgid=%u }", |
167 | stamp.year, stamp.month, stamp.day, stamp.hour, | |
168 | stamp.min, stamp.sec, r->profile, tomoyo_mode[r->mode], | |
169 | tomoyo_yesno(r->granted), gpid, tomoyo_sys_getpid(), | |
170 | tomoyo_sys_getppid(), | |
609fcd1b EB |
171 | from_kuid(&init_user_ns, current_uid()), |
172 | from_kgid(&init_user_ns, current_gid()), | |
173 | from_kuid(&init_user_ns, current_euid()), | |
174 | from_kgid(&init_user_ns, current_egid()), | |
175 | from_kuid(&init_user_ns, current_suid()), | |
176 | from_kgid(&init_user_ns, current_sgid()), | |
177 | from_kuid(&init_user_ns, current_fsuid()), | |
178 | from_kgid(&init_user_ns, current_fsgid())); | |
8761afd4 TH |
179 | if (!obj) |
180 | goto no_obj_info; | |
181 | if (!obj->validate_done) { | |
182 | tomoyo_get_attributes(obj); | |
183 | obj->validate_done = true; | |
184 | } | |
185 | for (i = 0; i < TOMOYO_MAX_PATH_STAT; i++) { | |
186 | struct tomoyo_mini_stat *stat; | |
187 | unsigned int dev; | |
d179333f | 188 | umode_t mode; |
cdcf6723 | 189 | |
8761afd4 TH |
190 | if (!obj->stat_valid[i]) |
191 | continue; | |
192 | stat = &obj->stat[i]; | |
193 | dev = stat->dev; | |
194 | mode = stat->mode; | |
195 | if (i & 1) { | |
196 | pos += snprintf(buffer + pos, | |
197 | tomoyo_buffer_len - 1 - pos, | |
cdcf6723 TH |
198 | " path%u.parent={ uid=%u gid=%u ino=%lu perm=0%o }", |
199 | (i >> 1) + 1, | |
609fcd1b EB |
200 | from_kuid(&init_user_ns, stat->uid), |
201 | from_kgid(&init_user_ns, stat->gid), | |
202 | (unsigned long)stat->ino, | |
203 | stat->mode & S_IALLUGO); | |
8761afd4 TH |
204 | continue; |
205 | } | |
206 | pos += snprintf(buffer + pos, tomoyo_buffer_len - 1 - pos, | |
cdcf6723 TH |
207 | " path%u={ uid=%u gid=%u ino=%lu major=%u minor=%u perm=0%o type=%s", |
208 | (i >> 1) + 1, | |
609fcd1b EB |
209 | from_kuid(&init_user_ns, stat->uid), |
210 | from_kgid(&init_user_ns, stat->gid), | |
211 | (unsigned long)stat->ino, | |
212 | MAJOR(dev), MINOR(dev), | |
8761afd4 TH |
213 | mode & S_IALLUGO, tomoyo_filetype(mode)); |
214 | if (S_ISCHR(mode) || S_ISBLK(mode)) { | |
215 | dev = stat->rdev; | |
216 | pos += snprintf(buffer + pos, | |
217 | tomoyo_buffer_len - 1 - pos, | |
218 | " dev_major=%u dev_minor=%u", | |
219 | MAJOR(dev), MINOR(dev)); | |
220 | } | |
221 | pos += snprintf(buffer + pos, tomoyo_buffer_len - 1 - pos, | |
222 | " }"); | |
223 | } | |
224 | no_obj_info: | |
2066a361 TH |
225 | if (pos < tomoyo_buffer_len - 1) |
226 | return buffer; | |
227 | kfree(buffer); | |
228 | return NULL; | |
eadd99cc TH |
229 | } |
230 | ||
231 | /** | |
232 | * tomoyo_init_log - Allocate buffer for audit logs. | |
233 | * | |
234 | * @r: Pointer to "struct tomoyo_request_info". | |
235 | * @len: Buffer size needed for @fmt and @args. | |
236 | * @fmt: The printf()'s format string. | |
237 | * @args: va_list structure for @fmt. | |
238 | * | |
239 | * Returns pointer to allocated memory. | |
240 | * | |
241 | * This function uses kzalloc(), so caller must kfree() if this function | |
242 | * didn't return NULL. | |
243 | */ | |
244 | char *tomoyo_init_log(struct tomoyo_request_info *r, int len, const char *fmt, | |
245 | va_list args) | |
246 | { | |
247 | char *buf = NULL; | |
5b636857 | 248 | char *bprm_info = NULL; |
eadd99cc | 249 | const char *header = NULL; |
2ca9bf45 TH |
250 | char *realpath = NULL; |
251 | const char *symlink = NULL; | |
eadd99cc | 252 | int pos; |
ea504819 | 253 | const char *domainname = r->domain->domainname->name; |
cdcf6723 | 254 | |
eadd99cc TH |
255 | header = tomoyo_print_header(r); |
256 | if (!header) | |
257 | return NULL; | |
258 | /* +10 is for '\n' etc. and '\0'. */ | |
259 | len += strlen(domainname) + strlen(header) + 10; | |
2ca9bf45 TH |
260 | if (r->ee) { |
261 | struct file *file = r->ee->bprm->file; | |
cdcf6723 | 262 | |
2ca9bf45 | 263 | realpath = tomoyo_realpath_from_path(&file->f_path); |
5b636857 TH |
264 | bprm_info = tomoyo_print_bprm(r->ee->bprm, &r->ee->dump); |
265 | if (!realpath || !bprm_info) | |
2ca9bf45 | 266 | goto out; |
5b636857 TH |
267 | /* +80 is for " exec={ realpath=\"%s\" argc=%d envc=%d %s }" */ |
268 | len += strlen(realpath) + 80 + strlen(bprm_info); | |
2ca9bf45 TH |
269 | } else if (r->obj && r->obj->symlink_target) { |
270 | symlink = r->obj->symlink_target->name; | |
271 | /* +18 is for " symlink.target=\"%s\"" */ | |
272 | len += 18 + strlen(symlink); | |
273 | } | |
eadd99cc TH |
274 | len = tomoyo_round2(len); |
275 | buf = kzalloc(len, GFP_NOFS); | |
276 | if (!buf) | |
277 | goto out; | |
278 | len--; | |
279 | pos = snprintf(buf, len, "%s", header); | |
2ca9bf45 | 280 | if (realpath) { |
5b636857 | 281 | struct linux_binprm *bprm = r->ee->bprm; |
cdcf6723 | 282 | |
2ca9bf45 | 283 | pos += snprintf(buf + pos, len - pos, |
5b636857 TH |
284 | " exec={ realpath=\"%s\" argc=%d envc=%d %s }", |
285 | realpath, bprm->argc, bprm->envc, bprm_info); | |
2ca9bf45 TH |
286 | } else if (symlink) |
287 | pos += snprintf(buf + pos, len - pos, " symlink.target=\"%s\"", | |
288 | symlink); | |
eadd99cc TH |
289 | pos += snprintf(buf + pos, len - pos, "\n%s\n", domainname); |
290 | vsnprintf(buf + pos, len - pos, fmt, args); | |
291 | out: | |
2ca9bf45 | 292 | kfree(realpath); |
5b636857 | 293 | kfree(bprm_info); |
eadd99cc TH |
294 | kfree(header); |
295 | return buf; | |
296 | } | |
297 | ||
298 | /* Wait queue for /sys/kernel/security/tomoyo/audit. */ | |
299 | static DECLARE_WAIT_QUEUE_HEAD(tomoyo_log_wait); | |
300 | ||
301 | /* Structure for audit log. */ | |
302 | struct tomoyo_log { | |
303 | struct list_head list; | |
304 | char *log; | |
305 | int size; | |
306 | }; | |
307 | ||
308 | /* The list for "struct tomoyo_log". */ | |
309 | static LIST_HEAD(tomoyo_log); | |
310 | ||
311 | /* Lock for "struct list_head tomoyo_log". */ | |
312 | static DEFINE_SPINLOCK(tomoyo_log_lock); | |
313 | ||
15269fb1 | 314 | /* Length of "struct list_head tomoyo_log". */ |
eadd99cc TH |
315 | static unsigned int tomoyo_log_count; |
316 | ||
317 | /** | |
318 | * tomoyo_get_audit - Get audit mode. | |
319 | * | |
bd03a3e4 | 320 | * @ns: Pointer to "struct tomoyo_policy_namespace". |
eadd99cc TH |
321 | * @profile: Profile number. |
322 | * @index: Index number of functionality. | |
323 | * @is_granted: True if granted log, false otherwise. | |
324 | * | |
325 | * Returns true if this request should be audited, false otherwise. | |
326 | */ | |
bd03a3e4 TH |
327 | static bool tomoyo_get_audit(const struct tomoyo_policy_namespace *ns, |
328 | const u8 profile, const u8 index, | |
1f067a68 | 329 | const struct tomoyo_acl_info *matched_acl, |
eadd99cc TH |
330 | const bool is_granted) |
331 | { | |
332 | u8 mode; | |
2c47ab93 TH |
333 | const u8 category = tomoyo_index2category[index] + |
334 | TOMOYO_MAX_MAC_INDEX; | |
eadd99cc | 335 | struct tomoyo_profile *p; |
cdcf6723 | 336 | |
eadd99cc TH |
337 | if (!tomoyo_policy_loaded) |
338 | return false; | |
bd03a3e4 | 339 | p = tomoyo_profile(ns, profile); |
eadd99cc TH |
340 | if (tomoyo_log_count >= p->pref[TOMOYO_PREF_MAX_AUDIT_LOG]) |
341 | return false; | |
1f067a68 TH |
342 | if (is_granted && matched_acl && matched_acl->cond && |
343 | matched_acl->cond->grant_log != TOMOYO_GRANTLOG_AUTO) | |
344 | return matched_acl->cond->grant_log == TOMOYO_GRANTLOG_YES; | |
eadd99cc TH |
345 | mode = p->config[index]; |
346 | if (mode == TOMOYO_CONFIG_USE_DEFAULT) | |
347 | mode = p->config[category]; | |
348 | if (mode == TOMOYO_CONFIG_USE_DEFAULT) | |
349 | mode = p->default_config; | |
350 | if (is_granted) | |
351 | return mode & TOMOYO_CONFIG_WANT_GRANT_LOG; | |
352 | return mode & TOMOYO_CONFIG_WANT_REJECT_LOG; | |
353 | } | |
354 | ||
355 | /** | |
356 | * tomoyo_write_log2 - Write an audit log. | |
357 | * | |
358 | * @r: Pointer to "struct tomoyo_request_info". | |
359 | * @len: Buffer size needed for @fmt and @args. | |
360 | * @fmt: The printf()'s format string. | |
361 | * @args: va_list structure for @fmt. | |
362 | * | |
363 | * Returns nothing. | |
364 | */ | |
365 | void tomoyo_write_log2(struct tomoyo_request_info *r, int len, const char *fmt, | |
366 | va_list args) | |
367 | { | |
368 | char *buf; | |
369 | struct tomoyo_log *entry; | |
370 | bool quota_exceeded = false; | |
cdcf6723 | 371 | |
1f067a68 TH |
372 | if (!tomoyo_get_audit(r->domain->ns, r->profile, r->type, |
373 | r->matched_acl, r->granted)) | |
eadd99cc TH |
374 | goto out; |
375 | buf = tomoyo_init_log(r, len, fmt, args); | |
376 | if (!buf) | |
377 | goto out; | |
378 | entry = kzalloc(sizeof(*entry), GFP_NOFS); | |
379 | if (!entry) { | |
380 | kfree(buf); | |
381 | goto out; | |
382 | } | |
383 | entry->log = buf; | |
384 | len = tomoyo_round2(strlen(buf) + 1); | |
385 | /* | |
386 | * The entry->size is used for memory quota checks. | |
387 | * Don't go beyond strlen(entry->log). | |
388 | */ | |
389 | entry->size = len + tomoyo_round2(sizeof(*entry)); | |
390 | spin_lock(&tomoyo_log_lock); | |
391 | if (tomoyo_memory_quota[TOMOYO_MEMORY_AUDIT] && | |
392 | tomoyo_memory_used[TOMOYO_MEMORY_AUDIT] + entry->size >= | |
393 | tomoyo_memory_quota[TOMOYO_MEMORY_AUDIT]) { | |
394 | quota_exceeded = true; | |
395 | } else { | |
396 | tomoyo_memory_used[TOMOYO_MEMORY_AUDIT] += entry->size; | |
397 | list_add_tail(&entry->list, &tomoyo_log); | |
398 | tomoyo_log_count++; | |
399 | } | |
400 | spin_unlock(&tomoyo_log_lock); | |
401 | if (quota_exceeded) { | |
402 | kfree(buf); | |
403 | kfree(entry); | |
404 | goto out; | |
405 | } | |
406 | wake_up(&tomoyo_log_wait); | |
407 | out: | |
408 | return; | |
409 | } | |
410 | ||
411 | /** | |
412 | * tomoyo_write_log - Write an audit log. | |
413 | * | |
414 | * @r: Pointer to "struct tomoyo_request_info". | |
415 | * @fmt: The printf()'s format string, followed by parameters. | |
416 | * | |
417 | * Returns nothing. | |
418 | */ | |
419 | void tomoyo_write_log(struct tomoyo_request_info *r, const char *fmt, ...) | |
420 | { | |
421 | va_list args; | |
422 | int len; | |
cdcf6723 | 423 | |
eadd99cc TH |
424 | va_start(args, fmt); |
425 | len = vsnprintf((char *) &len, 1, fmt, args) + 1; | |
426 | va_end(args); | |
427 | va_start(args, fmt); | |
428 | tomoyo_write_log2(r, len, fmt, args); | |
429 | va_end(args); | |
430 | } | |
431 | ||
432 | /** | |
433 | * tomoyo_read_log - Read an audit log. | |
434 | * | |
435 | * @head: Pointer to "struct tomoyo_io_buffer". | |
436 | * | |
437 | * Returns nothing. | |
438 | */ | |
439 | void tomoyo_read_log(struct tomoyo_io_buffer *head) | |
440 | { | |
441 | struct tomoyo_log *ptr = NULL; | |
cdcf6723 | 442 | |
eadd99cc TH |
443 | if (head->r.w_pos) |
444 | return; | |
445 | kfree(head->read_buf); | |
446 | head->read_buf = NULL; | |
447 | spin_lock(&tomoyo_log_lock); | |
448 | if (!list_empty(&tomoyo_log)) { | |
449 | ptr = list_entry(tomoyo_log.next, typeof(*ptr), list); | |
450 | list_del(&ptr->list); | |
451 | tomoyo_log_count--; | |
452 | tomoyo_memory_used[TOMOYO_MEMORY_AUDIT] -= ptr->size; | |
453 | } | |
454 | spin_unlock(&tomoyo_log_lock); | |
455 | if (ptr) { | |
456 | head->read_buf = ptr->log; | |
457 | head->r.w[head->r.w_pos++] = head->read_buf; | |
458 | kfree(ptr); | |
459 | } | |
460 | } | |
461 | ||
462 | /** | |
463 | * tomoyo_poll_log - Wait for an audit log. | |
464 | * | |
465 | * @file: Pointer to "struct file". | |
6041e834 | 466 | * @wait: Pointer to "poll_table". Maybe NULL. |
eadd99cc | 467 | * |
a9a08845 | 468 | * Returns EPOLLIN | EPOLLRDNORM when ready to read an audit log. |
eadd99cc | 469 | */ |
c0d4be28 | 470 | __poll_t tomoyo_poll_log(struct file *file, poll_table *wait) |
eadd99cc TH |
471 | { |
472 | if (tomoyo_log_count) | |
a9a08845 | 473 | return EPOLLIN | EPOLLRDNORM; |
eadd99cc TH |
474 | poll_wait(file, &tomoyo_log_wait, wait); |
475 | if (tomoyo_log_count) | |
a9a08845 | 476 | return EPOLLIN | EPOLLRDNORM; |
eadd99cc TH |
477 | return 0; |
478 | } |