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