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Tetsuo Handaeadd99c2011-06-26 23:18:58 +09001/*
2 * security/tomoyo/audit.c
3 *
Tetsuo Handa0f2a55d2011-07-14 14:46:51 +09004 * Copyright (C) 2005-2011 NTT DATA CORPORATION
Tetsuo Handaeadd99c2011-06-26 23:18:58 +09005 */
6
7#include "common.h"
8#include <linux/slab.h>
9
10/**
Tetsuo Handa5b636852011-07-08 13:24:54 +090011 * 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 */
21static 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;
102out:
103 snprintf(buffer, tomoyo_buffer_len - 1,
104 "argv[]={ ... } envp[]= { ... }");
105 return buffer;
106}
107
108/**
Tetsuo Handa8761afd2011-07-08 13:22:41 +0900109 * tomoyo_filetype - Get string representation of file type.
110 *
111 * @mode: Mode value for stat().
112 *
113 * Returns file type string.
114 */
Al Virod179333f2011-08-26 23:03:17 -0400115static inline const char *tomoyo_filetype(const umode_t mode)
Tetsuo Handa8761afd2011-07-08 13:22:41 +0900116{
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
137/**
Tetsuo Handaeadd99c2011-06-26 23:18:58 +0900138 * 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 */
147static char *tomoyo_print_header(struct tomoyo_request_info *r)
148{
149 struct tomoyo_time stamp;
150 const pid_t gpid = task_pid_nr(current);
Tetsuo Handa8761afd2011-07-08 13:22:41 +0900151 struct tomoyo_obj_info *obj = r->obj;
Tetsuo Handaeadd99c2011-06-26 23:18:58 +0900152 static const int tomoyo_buffer_len = 4096;
153 char *buffer = kmalloc(tomoyo_buffer_len, GFP_NOFS);
Tetsuo Handa2066a362011-07-08 13:21:37 +0900154 int pos;
Tetsuo Handa8761afd2011-07-08 13:22:41 +0900155 u8 i;
Tetsuo Handaeadd99c2011-06-26 23:18:58 +0900156 if (!buffer)
157 return NULL;
Thomas Gleixner77f4fa02014-06-11 23:59:19 +0000158
159 tomoyo_convert_time(get_seconds(), &stamp);
160
Tetsuo Handa2066a362011-07-08 13:21:37 +0900161 pos = snprintf(buffer, tomoyo_buffer_len - 1,
162 "#%04u/%02u/%02u %02u:%02u:%02u# profile=%u mode=%s "
163 "granted=%s (global-pid=%u) task={ pid=%u ppid=%u "
164 "uid=%u gid=%u euid=%u egid=%u suid=%u sgid=%u "
165 "fsuid=%u fsgid=%u }", stamp.year, stamp.month,
166 stamp.day, stamp.hour, stamp.min, stamp.sec, r->profile,
167 tomoyo_mode[r->mode], tomoyo_yesno(r->granted), gpid,
168 tomoyo_sys_getpid(), tomoyo_sys_getppid(),
Eric W. Biederman609fcd12012-02-07 16:34:10 -0800169 from_kuid(&init_user_ns, current_uid()),
170 from_kgid(&init_user_ns, current_gid()),
171 from_kuid(&init_user_ns, current_euid()),
172 from_kgid(&init_user_ns, current_egid()),
173 from_kuid(&init_user_ns, current_suid()),
174 from_kgid(&init_user_ns, current_sgid()),
175 from_kuid(&init_user_ns, current_fsuid()),
176 from_kgid(&init_user_ns, current_fsgid()));
Tetsuo Handa8761afd2011-07-08 13:22:41 +0900177 if (!obj)
178 goto no_obj_info;
179 if (!obj->validate_done) {
180 tomoyo_get_attributes(obj);
181 obj->validate_done = true;
182 }
183 for (i = 0; i < TOMOYO_MAX_PATH_STAT; i++) {
184 struct tomoyo_mini_stat *stat;
185 unsigned int dev;
Al Virod179333f2011-08-26 23:03:17 -0400186 umode_t mode;
Tetsuo Handa8761afd2011-07-08 13:22:41 +0900187 if (!obj->stat_valid[i])
188 continue;
189 stat = &obj->stat[i];
190 dev = stat->dev;
191 mode = stat->mode;
192 if (i & 1) {
193 pos += snprintf(buffer + pos,
194 tomoyo_buffer_len - 1 - pos,
195 " path%u.parent={ uid=%u gid=%u "
196 "ino=%lu perm=0%o }", (i >> 1) + 1,
Eric W. Biederman609fcd12012-02-07 16:34:10 -0800197 from_kuid(&init_user_ns, stat->uid),
198 from_kgid(&init_user_ns, stat->gid),
199 (unsigned long)stat->ino,
200 stat->mode & S_IALLUGO);
Tetsuo Handa8761afd2011-07-08 13:22:41 +0900201 continue;
202 }
203 pos += snprintf(buffer + pos, tomoyo_buffer_len - 1 - pos,
204 " path%u={ uid=%u gid=%u ino=%lu major=%u"
205 " minor=%u perm=0%o type=%s", (i >> 1) + 1,
Eric W. Biederman609fcd12012-02-07 16:34:10 -0800206 from_kuid(&init_user_ns, stat->uid),
207 from_kgid(&init_user_ns, stat->gid),
208 (unsigned long)stat->ino,
209 MAJOR(dev), MINOR(dev),
Tetsuo Handa8761afd2011-07-08 13:22:41 +0900210 mode & S_IALLUGO, tomoyo_filetype(mode));
211 if (S_ISCHR(mode) || S_ISBLK(mode)) {
212 dev = stat->rdev;
213 pos += snprintf(buffer + pos,
214 tomoyo_buffer_len - 1 - pos,
215 " dev_major=%u dev_minor=%u",
216 MAJOR(dev), MINOR(dev));
217 }
218 pos += snprintf(buffer + pos, tomoyo_buffer_len - 1 - pos,
219 " }");
220 }
221no_obj_info:
Tetsuo Handa2066a362011-07-08 13:21:37 +0900222 if (pos < tomoyo_buffer_len - 1)
223 return buffer;
224 kfree(buffer);
225 return NULL;
Tetsuo Handaeadd99c2011-06-26 23:18:58 +0900226}
227
228/**
229 * tomoyo_init_log - Allocate buffer for audit logs.
230 *
231 * @r: Pointer to "struct tomoyo_request_info".
232 * @len: Buffer size needed for @fmt and @args.
233 * @fmt: The printf()'s format string.
234 * @args: va_list structure for @fmt.
235 *
236 * Returns pointer to allocated memory.
237 *
238 * This function uses kzalloc(), so caller must kfree() if this function
239 * didn't return NULL.
240 */
241char *tomoyo_init_log(struct tomoyo_request_info *r, int len, const char *fmt,
242 va_list args)
243{
244 char *buf = NULL;
Tetsuo Handa5b636852011-07-08 13:24:54 +0900245 char *bprm_info = NULL;
Tetsuo Handaeadd99c2011-06-26 23:18:58 +0900246 const char *header = NULL;
Tetsuo Handa2ca9bf42011-07-08 13:23:44 +0900247 char *realpath = NULL;
248 const char *symlink = NULL;
Tetsuo Handaeadd99c2011-06-26 23:18:58 +0900249 int pos;
Tetsuo Handaea504812011-06-30 17:32:30 +0900250 const char *domainname = r->domain->domainname->name;
Tetsuo Handaeadd99c2011-06-26 23:18:58 +0900251 header = tomoyo_print_header(r);
252 if (!header)
253 return NULL;
254 /* +10 is for '\n' etc. and '\0'. */
255 len += strlen(domainname) + strlen(header) + 10;
Tetsuo Handa2ca9bf42011-07-08 13:23:44 +0900256 if (r->ee) {
257 struct file *file = r->ee->bprm->file;
258 realpath = tomoyo_realpath_from_path(&file->f_path);
Tetsuo Handa5b636852011-07-08 13:24:54 +0900259 bprm_info = tomoyo_print_bprm(r->ee->bprm, &r->ee->dump);
260 if (!realpath || !bprm_info)
Tetsuo Handa2ca9bf42011-07-08 13:23:44 +0900261 goto out;
Tetsuo Handa5b636852011-07-08 13:24:54 +0900262 /* +80 is for " exec={ realpath=\"%s\" argc=%d envc=%d %s }" */
263 len += strlen(realpath) + 80 + strlen(bprm_info);
Tetsuo Handa2ca9bf42011-07-08 13:23:44 +0900264 } else if (r->obj && r->obj->symlink_target) {
265 symlink = r->obj->symlink_target->name;
266 /* +18 is for " symlink.target=\"%s\"" */
267 len += 18 + strlen(symlink);
268 }
Tetsuo Handaeadd99c2011-06-26 23:18:58 +0900269 len = tomoyo_round2(len);
270 buf = kzalloc(len, GFP_NOFS);
271 if (!buf)
272 goto out;
273 len--;
274 pos = snprintf(buf, len, "%s", header);
Tetsuo Handa2ca9bf42011-07-08 13:23:44 +0900275 if (realpath) {
Tetsuo Handa5b636852011-07-08 13:24:54 +0900276 struct linux_binprm *bprm = r->ee->bprm;
Tetsuo Handa2ca9bf42011-07-08 13:23:44 +0900277 pos += snprintf(buf + pos, len - pos,
Tetsuo Handa5b636852011-07-08 13:24:54 +0900278 " exec={ realpath=\"%s\" argc=%d envc=%d %s }",
279 realpath, bprm->argc, bprm->envc, bprm_info);
Tetsuo Handa2ca9bf42011-07-08 13:23:44 +0900280 } else if (symlink)
281 pos += snprintf(buf + pos, len - pos, " symlink.target=\"%s\"",
282 symlink);
Tetsuo Handaeadd99c2011-06-26 23:18:58 +0900283 pos += snprintf(buf + pos, len - pos, "\n%s\n", domainname);
284 vsnprintf(buf + pos, len - pos, fmt, args);
285out:
Tetsuo Handa2ca9bf42011-07-08 13:23:44 +0900286 kfree(realpath);
Tetsuo Handa5b636852011-07-08 13:24:54 +0900287 kfree(bprm_info);
Tetsuo Handaeadd99c2011-06-26 23:18:58 +0900288 kfree(header);
289 return buf;
290}
291
292/* Wait queue for /sys/kernel/security/tomoyo/audit. */
293static DECLARE_WAIT_QUEUE_HEAD(tomoyo_log_wait);
294
295/* Structure for audit log. */
296struct tomoyo_log {
297 struct list_head list;
298 char *log;
299 int size;
300};
301
302/* The list for "struct tomoyo_log". */
303static LIST_HEAD(tomoyo_log);
304
305/* Lock for "struct list_head tomoyo_log". */
306static DEFINE_SPINLOCK(tomoyo_log_lock);
307
308/* Length of "stuct list_head tomoyo_log". */
309static unsigned int tomoyo_log_count;
310
311/**
312 * tomoyo_get_audit - Get audit mode.
313 *
Tetsuo Handabd03a3e2011-06-26 23:19:52 +0900314 * @ns: Pointer to "struct tomoyo_policy_namespace".
Tetsuo Handaeadd99c2011-06-26 23:18:58 +0900315 * @profile: Profile number.
316 * @index: Index number of functionality.
317 * @is_granted: True if granted log, false otherwise.
318 *
319 * Returns true if this request should be audited, false otherwise.
320 */
Tetsuo Handabd03a3e2011-06-26 23:19:52 +0900321static bool tomoyo_get_audit(const struct tomoyo_policy_namespace *ns,
322 const u8 profile, const u8 index,
Tetsuo Handa1f067a62011-09-10 15:24:56 +0900323 const struct tomoyo_acl_info *matched_acl,
Tetsuo Handaeadd99c2011-06-26 23:18:58 +0900324 const bool is_granted)
325{
326 u8 mode;
Tetsuo Handa2c47ab92011-06-26 23:21:19 +0900327 const u8 category = tomoyo_index2category[index] +
328 TOMOYO_MAX_MAC_INDEX;
Tetsuo Handaeadd99c2011-06-26 23:18:58 +0900329 struct tomoyo_profile *p;
330 if (!tomoyo_policy_loaded)
331 return false;
Tetsuo Handabd03a3e2011-06-26 23:19:52 +0900332 p = tomoyo_profile(ns, profile);
Tetsuo Handaeadd99c2011-06-26 23:18:58 +0900333 if (tomoyo_log_count >= p->pref[TOMOYO_PREF_MAX_AUDIT_LOG])
334 return false;
Tetsuo Handa1f067a62011-09-10 15:24:56 +0900335 if (is_granted && matched_acl && matched_acl->cond &&
336 matched_acl->cond->grant_log != TOMOYO_GRANTLOG_AUTO)
337 return matched_acl->cond->grant_log == TOMOYO_GRANTLOG_YES;
Tetsuo Handaeadd99c2011-06-26 23:18:58 +0900338 mode = p->config[index];
339 if (mode == TOMOYO_CONFIG_USE_DEFAULT)
340 mode = p->config[category];
341 if (mode == TOMOYO_CONFIG_USE_DEFAULT)
342 mode = p->default_config;
343 if (is_granted)
344 return mode & TOMOYO_CONFIG_WANT_GRANT_LOG;
345 return mode & TOMOYO_CONFIG_WANT_REJECT_LOG;
346}
347
348/**
349 * tomoyo_write_log2 - Write an audit log.
350 *
351 * @r: Pointer to "struct tomoyo_request_info".
352 * @len: Buffer size needed for @fmt and @args.
353 * @fmt: The printf()'s format string.
354 * @args: va_list structure for @fmt.
355 *
356 * Returns nothing.
357 */
358void tomoyo_write_log2(struct tomoyo_request_info *r, int len, const char *fmt,
359 va_list args)
360{
361 char *buf;
362 struct tomoyo_log *entry;
363 bool quota_exceeded = false;
Tetsuo Handa1f067a62011-09-10 15:24:56 +0900364 if (!tomoyo_get_audit(r->domain->ns, r->profile, r->type,
365 r->matched_acl, r->granted))
Tetsuo Handaeadd99c2011-06-26 23:18:58 +0900366 goto out;
367 buf = tomoyo_init_log(r, len, fmt, args);
368 if (!buf)
369 goto out;
370 entry = kzalloc(sizeof(*entry), GFP_NOFS);
371 if (!entry) {
372 kfree(buf);
373 goto out;
374 }
375 entry->log = buf;
376 len = tomoyo_round2(strlen(buf) + 1);
377 /*
378 * The entry->size is used for memory quota checks.
379 * Don't go beyond strlen(entry->log).
380 */
381 entry->size = len + tomoyo_round2(sizeof(*entry));
382 spin_lock(&tomoyo_log_lock);
383 if (tomoyo_memory_quota[TOMOYO_MEMORY_AUDIT] &&
384 tomoyo_memory_used[TOMOYO_MEMORY_AUDIT] + entry->size >=
385 tomoyo_memory_quota[TOMOYO_MEMORY_AUDIT]) {
386 quota_exceeded = true;
387 } else {
388 tomoyo_memory_used[TOMOYO_MEMORY_AUDIT] += entry->size;
389 list_add_tail(&entry->list, &tomoyo_log);
390 tomoyo_log_count++;
391 }
392 spin_unlock(&tomoyo_log_lock);
393 if (quota_exceeded) {
394 kfree(buf);
395 kfree(entry);
396 goto out;
397 }
398 wake_up(&tomoyo_log_wait);
399out:
400 return;
401}
402
403/**
404 * tomoyo_write_log - Write an audit log.
405 *
406 * @r: Pointer to "struct tomoyo_request_info".
407 * @fmt: The printf()'s format string, followed by parameters.
408 *
409 * Returns nothing.
410 */
411void tomoyo_write_log(struct tomoyo_request_info *r, const char *fmt, ...)
412{
413 va_list args;
414 int len;
415 va_start(args, fmt);
416 len = vsnprintf((char *) &len, 1, fmt, args) + 1;
417 va_end(args);
418 va_start(args, fmt);
419 tomoyo_write_log2(r, len, fmt, args);
420 va_end(args);
421}
422
423/**
424 * tomoyo_read_log - Read an audit log.
425 *
426 * @head: Pointer to "struct tomoyo_io_buffer".
427 *
428 * Returns nothing.
429 */
430void tomoyo_read_log(struct tomoyo_io_buffer *head)
431{
432 struct tomoyo_log *ptr = NULL;
433 if (head->r.w_pos)
434 return;
435 kfree(head->read_buf);
436 head->read_buf = NULL;
437 spin_lock(&tomoyo_log_lock);
438 if (!list_empty(&tomoyo_log)) {
439 ptr = list_entry(tomoyo_log.next, typeof(*ptr), list);
440 list_del(&ptr->list);
441 tomoyo_log_count--;
442 tomoyo_memory_used[TOMOYO_MEMORY_AUDIT] -= ptr->size;
443 }
444 spin_unlock(&tomoyo_log_lock);
445 if (ptr) {
446 head->read_buf = ptr->log;
447 head->r.w[head->r.w_pos++] = head->read_buf;
448 kfree(ptr);
449 }
450}
451
452/**
453 * tomoyo_poll_log - Wait for an audit log.
454 *
455 * @file: Pointer to "struct file".
Tetsuo Handa6041e832012-03-14 18:27:49 +0900456 * @wait: Pointer to "poll_table". Maybe NULL.
Tetsuo Handaeadd99c2011-06-26 23:18:58 +0900457 *
458 * Returns POLLIN | POLLRDNORM when ready to read an audit log.
459 */
Tetsuo Handa6041e832012-03-14 18:27:49 +0900460unsigned int tomoyo_poll_log(struct file *file, poll_table *wait)
Tetsuo Handaeadd99c2011-06-26 23:18:58 +0900461{
462 if (tomoyo_log_count)
463 return POLLIN | POLLRDNORM;
464 poll_wait(file, &tomoyo_log_wait, wait);
465 if (tomoyo_log_count)
466 return POLLIN | POLLRDNORM;
467 return 0;
468}