1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com>
4 *
5 * Authors:
6 * Casey Schaufler <casey@schaufler-ca.com>
7 * Ahmed S. Darwish <darwish.07@gmail.com>
8 *
9 * Special thanks to the authors of selinuxfs.
10 *
11 * Karl MacMillan <kmacmillan@tresys.com>
12 * James Morris <jmorris@redhat.com>
13 */
14
15 #include <linux/kernel.h>
16 #include <linux/vmalloc.h>
17 #include <linux/security.h>
18 #include <linux/mutex.h>
19 #include <linux/slab.h>
20 #include <net/net_namespace.h>
21 #include <net/cipso_ipv4.h>
22 #include <linux/seq_file.h>
23 #include <linux/ctype.h>
24 #include <linux/audit.h>
25 #include <linux/magic.h>
26 #include <linux/fs_context.h>
27 #include "smack.h"
28
29 #define BEBITS (sizeof(__be32) * 8)
30 /*
31 * smackfs pseudo filesystem.
32 */
33
34 enum smk_inos {
35 SMK_ROOT_INO = 2,
36 SMK_LOAD = 3, /* load policy */
37 SMK_CIPSO = 4, /* load label -> CIPSO mapping */
38 SMK_DOI = 5, /* CIPSO DOI */
39 SMK_DIRECT = 6, /* CIPSO level indicating direct label */
40 SMK_AMBIENT = 7, /* internet ambient label */
41 SMK_NET4ADDR = 8, /* single label hosts */
42 SMK_ONLYCAP = 9, /* the only "capable" label */
43 SMK_LOGGING = 10, /* logging */
44 SMK_LOAD_SELF = 11, /* task specific rules */
45 SMK_ACCESSES = 12, /* access policy */
46 SMK_MAPPED = 13, /* CIPSO level indicating mapped label */
47 SMK_LOAD2 = 14, /* load policy with long labels */
48 SMK_LOAD_SELF2 = 15, /* load task specific rules with long labels */
49 SMK_ACCESS2 = 16, /* make an access check with long labels */
50 SMK_CIPSO2 = 17, /* load long label -> CIPSO mapping */
51 SMK_REVOKE_SUBJ = 18, /* set rules with subject label to '-' */
52 SMK_CHANGE_RULE = 19, /* change or add rules (long labels) */
53 SMK_SYSLOG = 20, /* change syslog label) */
54 SMK_PTRACE = 21, /* set ptrace rule */
55 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
56 SMK_UNCONFINED = 22, /* define an unconfined label */
57 #endif
58 #if IS_ENABLED(CONFIG_IPV6)
59 SMK_NET6ADDR = 23, /* single label IPv6 hosts */
60 #endif /* CONFIG_IPV6 */
61 SMK_RELABEL_SELF = 24, /* relabel possible without CAP_MAC_ADMIN */
62 };
63
64 /*
65 * List locks
66 */
67 static DEFINE_MUTEX(smack_cipso_lock);
68 static DEFINE_MUTEX(smack_ambient_lock);
69 static DEFINE_MUTEX(smk_net4addr_lock);
70 #if IS_ENABLED(CONFIG_IPV6)
71 static DEFINE_MUTEX(smk_net6addr_lock);
72 #endif /* CONFIG_IPV6 */
73
74 /*
75 * This is the "ambient" label for network traffic.
76 * If it isn't somehow marked, use this.
77 * It can be reset via smackfs/ambient
78 */
79 struct smack_known *smack_net_ambient;
80
81 /*
82 * This is the level in a CIPSO header that indicates a
83 * smack label is contained directly in the category set.
84 * It can be reset via smackfs/direct
85 */
86 int smack_cipso_direct = SMACK_CIPSO_DIRECT_DEFAULT;
87
88 /*
89 * This is the level in a CIPSO header that indicates a
90 * secid is contained directly in the category set.
91 * It can be reset via smackfs/mapped
92 */
93 int smack_cipso_mapped = SMACK_CIPSO_MAPPED_DEFAULT;
94
95 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
96 /*
97 * Allow one label to be unconfined. This is for
98 * debugging and application bring-up purposes only.
99 * It is bad and wrong, but everyone seems to expect
100 * to have it.
101 */
102 struct smack_known *smack_unconfined;
103 #endif
104
105 /*
106 * If this value is set restrict syslog use to the label specified.
107 * It can be reset via smackfs/syslog
108 */
109 struct smack_known *smack_syslog_label;
110
111 /*
112 * Ptrace current rule
113 * SMACK_PTRACE_DEFAULT regular smack ptrace rules (/proc based)
114 * SMACK_PTRACE_EXACT labels must match, but can be overriden with
115 * CAP_SYS_PTRACE
116 * SMACK_PTRACE_DRACONIAN lables must match, CAP_SYS_PTRACE has no effect
117 */
118 int smack_ptrace_rule = SMACK_PTRACE_DEFAULT;
119
120 /*
121 * Certain IP addresses may be designated as single label hosts.
122 * Packets are sent there unlabeled, but only from tasks that
123 * can write to the specified label.
124 */
125
126 LIST_HEAD(smk_net4addr_list);
127 #if IS_ENABLED(CONFIG_IPV6)
128 LIST_HEAD(smk_net6addr_list);
129 #endif /* CONFIG_IPV6 */
130
131 /*
132 * Rule lists are maintained for each label.
133 */
134 struct smack_parsed_rule {
135 struct smack_known *smk_subject;
136 struct smack_known *smk_object;
137 int smk_access1;
138 int smk_access2;
139 };
140
141 static int smk_cipso_doi_value = SMACK_CIPSO_DOI_DEFAULT;
142
143 /*
144 * Values for parsing cipso rules
145 * SMK_DIGITLEN: Length of a digit field in a rule.
146 * SMK_CIPSOMIN: Minimum possible cipso rule length.
147 * SMK_CIPSOMAX: Maximum possible cipso rule length.
148 */
149 #define SMK_DIGITLEN 4
150 #define SMK_CIPSOMIN (SMK_LABELLEN + 2 * SMK_DIGITLEN)
151 #define SMK_CIPSOMAX (SMK_CIPSOMIN + SMACK_CIPSO_MAXCATNUM * SMK_DIGITLEN)
152
153 /*
154 * Values for parsing MAC rules
155 * SMK_ACCESS: Maximum possible combination of access permissions
156 * SMK_ACCESSLEN: Maximum length for a rule access field
157 * SMK_LOADLEN: Smack rule length
158 */
159 #define SMK_OACCESS "rwxa"
160 #define SMK_ACCESS "rwxatl"
161 #define SMK_OACCESSLEN (sizeof(SMK_OACCESS) - 1)
162 #define SMK_ACCESSLEN (sizeof(SMK_ACCESS) - 1)
163 #define SMK_OLOADLEN (SMK_LABELLEN + SMK_LABELLEN + SMK_OACCESSLEN)
164 #define SMK_LOADLEN (SMK_LABELLEN + SMK_LABELLEN + SMK_ACCESSLEN)
165
166 /*
167 * Stricly for CIPSO level manipulation.
168 * Set the category bit number in a smack label sized buffer.
169 */
smack_catset_bit(unsigned int cat,char * catsetp)170 static inline void smack_catset_bit(unsigned int cat, char *catsetp)
171 {
172 if (cat == 0 || cat > (SMK_CIPSOLEN * 8))
173 return;
174
175 catsetp[(cat - 1) / 8] |= 0x80 >> ((cat - 1) % 8);
176 }
177
178 /**
179 * smk_netlabel_audit_set - fill a netlbl_audit struct
180 * @nap: structure to fill
181 */
smk_netlabel_audit_set(struct netlbl_audit * nap)182 static void smk_netlabel_audit_set(struct netlbl_audit *nap)
183 {
184 struct smack_known *skp = smk_of_current();
185
186 nap->loginuid = audit_get_loginuid(current);
187 nap->sessionid = audit_get_sessionid(current);
188 nap->secid = skp->smk_secid;
189 }
190
191 /*
192 * Value for parsing single label host rules
193 * "1.2.3.4 X"
194 */
195 #define SMK_NETLBLADDRMIN 9
196
197 /**
198 * smk_set_access - add a rule to the rule list or replace an old rule
199 * @srp: the rule to add or replace
200 * @rule_list: the list of rules
201 * @rule_lock: the rule list lock
202 *
203 * Looks through the current subject/object/access list for
204 * the subject/object pair and replaces the access that was
205 * there. If the pair isn't found add it with the specified
206 * access.
207 *
208 * Returns 0 if nothing goes wrong or -ENOMEM if it fails
209 * during the allocation of the new pair to add.
210 */
smk_set_access(struct smack_parsed_rule * srp,struct list_head * rule_list,struct mutex * rule_lock)211 static int smk_set_access(struct smack_parsed_rule *srp,
212 struct list_head *rule_list,
213 struct mutex *rule_lock)
214 {
215 struct smack_rule *sp;
216 int found = 0;
217 int rc = 0;
218
219 mutex_lock(rule_lock);
220
221 /*
222 * Because the object label is less likely to match
223 * than the subject label check it first
224 */
225 list_for_each_entry_rcu(sp, rule_list, list) {
226 if (sp->smk_object == srp->smk_object &&
227 sp->smk_subject == srp->smk_subject) {
228 found = 1;
229 sp->smk_access |= srp->smk_access1;
230 sp->smk_access &= ~srp->smk_access2;
231 break;
232 }
233 }
234
235 if (found == 0) {
236 sp = kmem_cache_zalloc(smack_rule_cache, GFP_KERNEL);
237 if (sp == NULL) {
238 rc = -ENOMEM;
239 goto out;
240 }
241
242 sp->smk_subject = srp->smk_subject;
243 sp->smk_object = srp->smk_object;
244 sp->smk_access = srp->smk_access1 & ~srp->smk_access2;
245
246 list_add_rcu(&sp->list, rule_list);
247 }
248
249 out:
250 mutex_unlock(rule_lock);
251 return rc;
252 }
253
254 /**
255 * smk_perm_from_str - parse smack accesses from a text string
256 * @string: a text string that contains a Smack accesses code
257 *
258 * Returns an integer with respective bits set for specified accesses.
259 */
smk_perm_from_str(const char * string)260 static int smk_perm_from_str(const char *string)
261 {
262 int perm = 0;
263 const char *cp;
264
265 for (cp = string; ; cp++)
266 switch (*cp) {
267 case '-':
268 break;
269 case 'r':
270 case 'R':
271 perm |= MAY_READ;
272 break;
273 case 'w':
274 case 'W':
275 perm |= MAY_WRITE;
276 break;
277 case 'x':
278 case 'X':
279 perm |= MAY_EXEC;
280 break;
281 case 'a':
282 case 'A':
283 perm |= MAY_APPEND;
284 break;
285 case 't':
286 case 'T':
287 perm |= MAY_TRANSMUTE;
288 break;
289 case 'l':
290 case 'L':
291 perm |= MAY_LOCK;
292 break;
293 case 'b':
294 case 'B':
295 perm |= MAY_BRINGUP;
296 break;
297 default:
298 return perm;
299 }
300 }
301
302 /**
303 * smk_fill_rule - Fill Smack rule from strings
304 * @subject: subject label string
305 * @object: object label string
306 * @access1: access string
307 * @access2: string with permissions to be removed
308 * @rule: Smack rule
309 * @import: if non-zero, import labels
310 * @len: label length limit
311 *
312 * Returns 0 on success, appropriate error code on failure.
313 */
smk_fill_rule(const char * subject,const char * object,const char * access1,const char * access2,struct smack_parsed_rule * rule,int import,int len)314 static int smk_fill_rule(const char *subject, const char *object,
315 const char *access1, const char *access2,
316 struct smack_parsed_rule *rule, int import,
317 int len)
318 {
319 const char *cp;
320 struct smack_known *skp;
321
322 if (import) {
323 rule->smk_subject = smk_import_entry(subject, len);
324 if (IS_ERR(rule->smk_subject))
325 return PTR_ERR(rule->smk_subject);
326
327 rule->smk_object = smk_import_entry(object, len);
328 if (IS_ERR(rule->smk_object))
329 return PTR_ERR(rule->smk_object);
330 } else {
331 cp = smk_parse_smack(subject, len);
332 if (IS_ERR(cp))
333 return PTR_ERR(cp);
334 skp = smk_find_entry(cp);
335 kfree(cp);
336 if (skp == NULL)
337 return -ENOENT;
338 rule->smk_subject = skp;
339
340 cp = smk_parse_smack(object, len);
341 if (IS_ERR(cp))
342 return PTR_ERR(cp);
343 skp = smk_find_entry(cp);
344 kfree(cp);
345 if (skp == NULL)
346 return -ENOENT;
347 rule->smk_object = skp;
348 }
349
350 rule->smk_access1 = smk_perm_from_str(access1);
351 if (access2)
352 rule->smk_access2 = smk_perm_from_str(access2);
353 else
354 rule->smk_access2 = ~rule->smk_access1;
355
356 return 0;
357 }
358
359 /**
360 * smk_parse_rule - parse Smack rule from load string
361 * @data: string to be parsed whose size is SMK_LOADLEN
362 * @rule: Smack rule
363 * @import: if non-zero, import labels
364 *
365 * Returns 0 on success, -1 on errors.
366 */
smk_parse_rule(const char * data,struct smack_parsed_rule * rule,int import)367 static int smk_parse_rule(const char *data, struct smack_parsed_rule *rule,
368 int import)
369 {
370 int rc;
371
372 rc = smk_fill_rule(data, data + SMK_LABELLEN,
373 data + SMK_LABELLEN + SMK_LABELLEN, NULL, rule,
374 import, SMK_LABELLEN);
375 return rc;
376 }
377
378 /**
379 * smk_parse_long_rule - parse Smack rule from rule string
380 * @data: string to be parsed, null terminated
381 * @rule: Will be filled with Smack parsed rule
382 * @import: if non-zero, import labels
383 * @tokens: numer of substrings expected in data
384 *
385 * Returns number of processed bytes on success, -ERRNO on failure.
386 */
smk_parse_long_rule(char * data,struct smack_parsed_rule * rule,int import,int tokens)387 static ssize_t smk_parse_long_rule(char *data, struct smack_parsed_rule *rule,
388 int import, int tokens)
389 {
390 ssize_t cnt = 0;
391 char *tok[4];
392 int rc;
393 int i;
394
395 /*
396 * Parsing the rule in-place, filling all white-spaces with '\0'
397 */
398 for (i = 0; i < tokens; ++i) {
399 while (isspace(data[cnt]))
400 data[cnt++] = '\0';
401
402 if (data[cnt] == '\0')
403 /* Unexpected end of data */
404 return -EINVAL;
405
406 tok[i] = data + cnt;
407
408 while (data[cnt] && !isspace(data[cnt]))
409 ++cnt;
410 }
411 while (isspace(data[cnt]))
412 data[cnt++] = '\0';
413
414 while (i < 4)
415 tok[i++] = NULL;
416
417 rc = smk_fill_rule(tok[0], tok[1], tok[2], tok[3], rule, import, 0);
418 return rc == 0 ? cnt : rc;
419 }
420
421 #define SMK_FIXED24_FMT 0 /* Fixed 24byte label format */
422 #define SMK_LONG_FMT 1 /* Variable long label format */
423 #define SMK_CHANGE_FMT 2 /* Rule modification format */
424 /**
425 * smk_write_rules_list - write() for any /smack rule file
426 * @file: file pointer, not actually used
427 * @buf: where to get the data from
428 * @count: bytes sent
429 * @ppos: where to start - must be 0
430 * @rule_list: the list of rules to write to
431 * @rule_lock: lock for the rule list
432 * @format: /smack/load or /smack/load2 or /smack/change-rule format.
433 *
434 * Get one smack access rule from above.
435 * The format for SMK_LONG_FMT is:
436 * "subject<whitespace>object<whitespace>access[<whitespace>...]"
437 * The format for SMK_FIXED24_FMT is exactly:
438 * "subject object rwxat"
439 * The format for SMK_CHANGE_FMT is:
440 * "subject<whitespace>object<whitespace>
441 * acc_enable<whitespace>acc_disable[<whitespace>...]"
442 */
smk_write_rules_list(struct file * file,const char __user * buf,size_t count,loff_t * ppos,struct list_head * rule_list,struct mutex * rule_lock,int format)443 static ssize_t smk_write_rules_list(struct file *file, const char __user *buf,
444 size_t count, loff_t *ppos,
445 struct list_head *rule_list,
446 struct mutex *rule_lock, int format)
447 {
448 struct smack_parsed_rule rule;
449 char *data;
450 int rc;
451 int trunc = 0;
452 int tokens;
453 ssize_t cnt = 0;
454
455 /*
456 * No partial writes.
457 * Enough data must be present.
458 */
459 if (*ppos != 0)
460 return -EINVAL;
461
462 if (format == SMK_FIXED24_FMT) {
463 /*
464 * Minor hack for backward compatibility
465 */
466 if (count < SMK_OLOADLEN || count > SMK_LOADLEN)
467 return -EINVAL;
468 } else {
469 if (count >= PAGE_SIZE) {
470 count = PAGE_SIZE - 1;
471 trunc = 1;
472 }
473 }
474
475 data = memdup_user_nul(buf, count);
476 if (IS_ERR(data))
477 return PTR_ERR(data);
478
479 /*
480 * In case of parsing only part of user buf,
481 * avoid having partial rule at the data buffer
482 */
483 if (trunc) {
484 while (count > 0 && (data[count - 1] != '\n'))
485 --count;
486 if (count == 0) {
487 rc = -EINVAL;
488 goto out;
489 }
490 }
491
492 data[count] = '\0';
493 tokens = (format == SMK_CHANGE_FMT ? 4 : 3);
494 while (cnt < count) {
495 if (format == SMK_FIXED24_FMT) {
496 rc = smk_parse_rule(data, &rule, 1);
497 if (rc < 0)
498 goto out;
499 cnt = count;
500 } else {
501 rc = smk_parse_long_rule(data + cnt, &rule, 1, tokens);
502 if (rc < 0)
503 goto out;
504 if (rc == 0) {
505 rc = -EINVAL;
506 goto out;
507 }
508 cnt += rc;
509 }
510
511 if (rule_list == NULL)
512 rc = smk_set_access(&rule, &rule.smk_subject->smk_rules,
513 &rule.smk_subject->smk_rules_lock);
514 else
515 rc = smk_set_access(&rule, rule_list, rule_lock);
516
517 if (rc)
518 goto out;
519 }
520
521 rc = cnt;
522 out:
523 kfree(data);
524 return rc;
525 }
526
527 /*
528 * Core logic for smackfs seq list operations.
529 */
530
smk_seq_start(struct seq_file * s,loff_t * pos,struct list_head * head)531 static void *smk_seq_start(struct seq_file *s, loff_t *pos,
532 struct list_head *head)
533 {
534 struct list_head *list;
535 int i = *pos;
536
537 rcu_read_lock();
538 for (list = rcu_dereference(list_next_rcu(head));
539 list != head;
540 list = rcu_dereference(list_next_rcu(list))) {
541 if (i-- == 0)
542 return list;
543 }
544
545 return NULL;
546 }
547
smk_seq_next(struct seq_file * s,void * v,loff_t * pos,struct list_head * head)548 static void *smk_seq_next(struct seq_file *s, void *v, loff_t *pos,
549 struct list_head *head)
550 {
551 struct list_head *list = v;
552
553 ++*pos;
554 list = rcu_dereference(list_next_rcu(list));
555
556 return (list == head) ? NULL : list;
557 }
558
smk_seq_stop(struct seq_file * s,void * v)559 static void smk_seq_stop(struct seq_file *s, void *v)
560 {
561 rcu_read_unlock();
562 }
563
smk_rule_show(struct seq_file * s,struct smack_rule * srp,int max)564 static void smk_rule_show(struct seq_file *s, struct smack_rule *srp, int max)
565 {
566 /*
567 * Don't show any rules with label names too long for
568 * interface file (/smack/load or /smack/load2)
569 * because you should expect to be able to write
570 * anything you read back.
571 */
572 if (strlen(srp->smk_subject->smk_known) >= max ||
573 strlen(srp->smk_object->smk_known) >= max)
574 return;
575
576 if (srp->smk_access == 0)
577 return;
578
579 seq_printf(s, "%s %s",
580 srp->smk_subject->smk_known,
581 srp->smk_object->smk_known);
582
583 seq_putc(s, ' ');
584
585 if (srp->smk_access & MAY_READ)
586 seq_putc(s, 'r');
587 if (srp->smk_access & MAY_WRITE)
588 seq_putc(s, 'w');
589 if (srp->smk_access & MAY_EXEC)
590 seq_putc(s, 'x');
591 if (srp->smk_access & MAY_APPEND)
592 seq_putc(s, 'a');
593 if (srp->smk_access & MAY_TRANSMUTE)
594 seq_putc(s, 't');
595 if (srp->smk_access & MAY_LOCK)
596 seq_putc(s, 'l');
597 if (srp->smk_access & MAY_BRINGUP)
598 seq_putc(s, 'b');
599
600 seq_putc(s, '\n');
601 }
602
603 /*
604 * Seq_file read operations for /smack/load
605 */
606
load2_seq_start(struct seq_file * s,loff_t * pos)607 static void *load2_seq_start(struct seq_file *s, loff_t *pos)
608 {
609 return smk_seq_start(s, pos, &smack_known_list);
610 }
611
load2_seq_next(struct seq_file * s,void * v,loff_t * pos)612 static void *load2_seq_next(struct seq_file *s, void *v, loff_t *pos)
613 {
614 return smk_seq_next(s, v, pos, &smack_known_list);
615 }
616
load_seq_show(struct seq_file * s,void * v)617 static int load_seq_show(struct seq_file *s, void *v)
618 {
619 struct list_head *list = v;
620 struct smack_rule *srp;
621 struct smack_known *skp =
622 list_entry_rcu(list, struct smack_known, list);
623
624 list_for_each_entry_rcu(srp, &skp->smk_rules, list)
625 smk_rule_show(s, srp, SMK_LABELLEN);
626
627 return 0;
628 }
629
630 static const struct seq_operations load_seq_ops = {
631 .start = load2_seq_start,
632 .next = load2_seq_next,
633 .show = load_seq_show,
634 .stop = smk_seq_stop,
635 };
636
637 /**
638 * smk_open_load - open() for /smack/load
639 * @inode: inode structure representing file
640 * @file: "load" file pointer
641 *
642 * For reading, use load_seq_* seq_file reading operations.
643 */
smk_open_load(struct inode * inode,struct file * file)644 static int smk_open_load(struct inode *inode, struct file *file)
645 {
646 return seq_open(file, &load_seq_ops);
647 }
648
649 /**
650 * smk_write_load - write() for /smack/load
651 * @file: file pointer, not actually used
652 * @buf: where to get the data from
653 * @count: bytes sent
654 * @ppos: where to start - must be 0
655 *
656 */
smk_write_load(struct file * file,const char __user * buf,size_t count,loff_t * ppos)657 static ssize_t smk_write_load(struct file *file, const char __user *buf,
658 size_t count, loff_t *ppos)
659 {
660 /*
661 * Must have privilege.
662 * No partial writes.
663 * Enough data must be present.
664 */
665 if (!smack_privileged(CAP_MAC_ADMIN))
666 return -EPERM;
667
668 return smk_write_rules_list(file, buf, count, ppos, NULL, NULL,
669 SMK_FIXED24_FMT);
670 }
671
672 static const struct file_operations smk_load_ops = {
673 .open = smk_open_load,
674 .read = seq_read,
675 .llseek = seq_lseek,
676 .write = smk_write_load,
677 .release = seq_release,
678 };
679
680 /**
681 * smk_cipso_doi - initialize the CIPSO domain
682 */
smk_cipso_doi(void)683 static void smk_cipso_doi(void)
684 {
685 int rc;
686 struct cipso_v4_doi *doip;
687 struct netlbl_audit nai;
688
689 smk_netlabel_audit_set(&nai);
690
691 rc = netlbl_cfg_map_del(NULL, PF_INET, NULL, NULL, &nai);
692 if (rc != 0)
693 printk(KERN_WARNING "%s:%d remove rc = %d\n",
694 __func__, __LINE__, rc);
695
696 doip = kmalloc(sizeof(struct cipso_v4_doi), GFP_KERNEL);
697 if (doip == NULL)
698 panic("smack: Failed to initialize cipso DOI.\n");
699 doip->map.std = NULL;
700 doip->doi = smk_cipso_doi_value;
701 doip->type = CIPSO_V4_MAP_PASS;
702 doip->tags[0] = CIPSO_V4_TAG_RBITMAP;
703 for (rc = 1; rc < CIPSO_V4_TAG_MAXCNT; rc++)
704 doip->tags[rc] = CIPSO_V4_TAG_INVALID;
705
706 rc = netlbl_cfg_cipsov4_add(doip, &nai);
707 if (rc != 0) {
708 printk(KERN_WARNING "%s:%d cipso add rc = %d\n",
709 __func__, __LINE__, rc);
710 kfree(doip);
711 return;
712 }
713 rc = netlbl_cfg_cipsov4_map_add(doip->doi, NULL, NULL, NULL, &nai);
714 if (rc != 0) {
715 printk(KERN_WARNING "%s:%d map add rc = %d\n",
716 __func__, __LINE__, rc);
717 kfree(doip);
718 return;
719 }
720 }
721
722 /**
723 * smk_unlbl_ambient - initialize the unlabeled domain
724 * @oldambient: previous domain string
725 */
smk_unlbl_ambient(char * oldambient)726 static void smk_unlbl_ambient(char *oldambient)
727 {
728 int rc;
729 struct netlbl_audit nai;
730
731 smk_netlabel_audit_set(&nai);
732
733 if (oldambient != NULL) {
734 rc = netlbl_cfg_map_del(oldambient, PF_INET, NULL, NULL, &nai);
735 if (rc != 0)
736 printk(KERN_WARNING "%s:%d remove rc = %d\n",
737 __func__, __LINE__, rc);
738 }
739 if (smack_net_ambient == NULL)
740 smack_net_ambient = &smack_known_floor;
741
742 rc = netlbl_cfg_unlbl_map_add(smack_net_ambient->smk_known, PF_INET,
743 NULL, NULL, &nai);
744 if (rc != 0)
745 printk(KERN_WARNING "%s:%d add rc = %d\n",
746 __func__, __LINE__, rc);
747 }
748
749 /*
750 * Seq_file read operations for /smack/cipso
751 */
752
cipso_seq_start(struct seq_file * s,loff_t * pos)753 static void *cipso_seq_start(struct seq_file *s, loff_t *pos)
754 {
755 return smk_seq_start(s, pos, &smack_known_list);
756 }
757
cipso_seq_next(struct seq_file * s,void * v,loff_t * pos)758 static void *cipso_seq_next(struct seq_file *s, void *v, loff_t *pos)
759 {
760 return smk_seq_next(s, v, pos, &smack_known_list);
761 }
762
763 /*
764 * Print cipso labels in format:
765 * label level[/cat[,cat]]
766 */
cipso_seq_show(struct seq_file * s,void * v)767 static int cipso_seq_show(struct seq_file *s, void *v)
768 {
769 struct list_head *list = v;
770 struct smack_known *skp =
771 list_entry_rcu(list, struct smack_known, list);
772 struct netlbl_lsm_catmap *cmp = skp->smk_netlabel.attr.mls.cat;
773 char sep = '/';
774 int i;
775
776 /*
777 * Don't show a label that could not have been set using
778 * /smack/cipso. This is in support of the notion that
779 * anything read from /smack/cipso ought to be writeable
780 * to /smack/cipso.
781 *
782 * /smack/cipso2 should be used instead.
783 */
784 if (strlen(skp->smk_known) >= SMK_LABELLEN)
785 return 0;
786
787 seq_printf(s, "%s %3d", skp->smk_known, skp->smk_netlabel.attr.mls.lvl);
788
789 for (i = netlbl_catmap_walk(cmp, 0); i >= 0;
790 i = netlbl_catmap_walk(cmp, i + 1)) {
791 seq_printf(s, "%c%d", sep, i);
792 sep = ',';
793 }
794
795 seq_putc(s, '\n');
796
797 return 0;
798 }
799
800 static const struct seq_operations cipso_seq_ops = {
801 .start = cipso_seq_start,
802 .next = cipso_seq_next,
803 .show = cipso_seq_show,
804 .stop = smk_seq_stop,
805 };
806
807 /**
808 * smk_open_cipso - open() for /smack/cipso
809 * @inode: inode structure representing file
810 * @file: "cipso" file pointer
811 *
812 * Connect our cipso_seq_* operations with /smack/cipso
813 * file_operations
814 */
smk_open_cipso(struct inode * inode,struct file * file)815 static int smk_open_cipso(struct inode *inode, struct file *file)
816 {
817 return seq_open(file, &cipso_seq_ops);
818 }
819
820 /**
821 * smk_set_cipso - do the work for write() for cipso and cipso2
822 * @file: file pointer, not actually used
823 * @buf: where to get the data from
824 * @count: bytes sent
825 * @ppos: where to start
826 * @format: /smack/cipso or /smack/cipso2
827 *
828 * Accepts only one cipso rule per write call.
829 * Returns number of bytes written or error code, as appropriate
830 */
smk_set_cipso(struct file * file,const char __user * buf,size_t count,loff_t * ppos,int format)831 static ssize_t smk_set_cipso(struct file *file, const char __user *buf,
832 size_t count, loff_t *ppos, int format)
833 {
834 struct smack_known *skp;
835 struct netlbl_lsm_secattr ncats;
836 char mapcatset[SMK_CIPSOLEN];
837 int maplevel;
838 unsigned int cat;
839 int catlen;
840 ssize_t rc = -EINVAL;
841 char *data = NULL;
842 char *rule;
843 int ret;
844 int i;
845
846 /*
847 * Must have privilege.
848 * No partial writes.
849 * Enough data must be present.
850 */
851 if (!smack_privileged(CAP_MAC_ADMIN))
852 return -EPERM;
853 if (*ppos != 0)
854 return -EINVAL;
855 if (format == SMK_FIXED24_FMT &&
856 (count < SMK_CIPSOMIN || count > SMK_CIPSOMAX))
857 return -EINVAL;
858
859 data = memdup_user_nul(buf, count);
860 if (IS_ERR(data))
861 return PTR_ERR(data);
862
863 rule = data;
864 /*
865 * Only allow one writer at a time. Writes should be
866 * quite rare and small in any case.
867 */
868 mutex_lock(&smack_cipso_lock);
869
870 skp = smk_import_entry(rule, 0);
871 if (IS_ERR(skp)) {
872 rc = PTR_ERR(skp);
873 goto out;
874 }
875
876 if (format == SMK_FIXED24_FMT)
877 rule += SMK_LABELLEN;
878 else
879 rule += strlen(skp->smk_known) + 1;
880
881 if (rule > data + count) {
882 rc = -EOVERFLOW;
883 goto out;
884 }
885
886 ret = sscanf(rule, "%d", &maplevel);
887 if (ret != 1 || maplevel < 0 || maplevel > SMACK_CIPSO_MAXLEVEL)
888 goto out;
889
890 rule += SMK_DIGITLEN;
891 if (rule > data + count) {
892 rc = -EOVERFLOW;
893 goto out;
894 }
895
896 ret = sscanf(rule, "%d", &catlen);
897 if (ret != 1 || catlen > SMACK_CIPSO_MAXCATNUM)
898 goto out;
899
900 if (format == SMK_FIXED24_FMT &&
901 count != (SMK_CIPSOMIN + catlen * SMK_DIGITLEN))
902 goto out;
903
904 memset(mapcatset, 0, sizeof(mapcatset));
905
906 for (i = 0; i < catlen; i++) {
907 rule += SMK_DIGITLEN;
908 if (rule > data + count) {
909 rc = -EOVERFLOW;
910 goto out;
911 }
912 ret = sscanf(rule, "%u", &cat);
913 if (ret != 1 || cat > SMACK_CIPSO_MAXCATNUM)
914 goto out;
915
916 smack_catset_bit(cat, mapcatset);
917 }
918
919 rc = smk_netlbl_mls(maplevel, mapcatset, &ncats, SMK_CIPSOLEN);
920 if (rc >= 0) {
921 netlbl_catmap_free(skp->smk_netlabel.attr.mls.cat);
922 skp->smk_netlabel.attr.mls.cat = ncats.attr.mls.cat;
923 skp->smk_netlabel.attr.mls.lvl = ncats.attr.mls.lvl;
924 rc = count;
925 /*
926 * This mapping may have been cached, so clear the cache.
927 */
928 netlbl_cache_invalidate();
929 }
930
931 out:
932 mutex_unlock(&smack_cipso_lock);
933 kfree(data);
934 return rc;
935 }
936
937 /**
938 * smk_write_cipso - write() for /smack/cipso
939 * @file: file pointer, not actually used
940 * @buf: where to get the data from
941 * @count: bytes sent
942 * @ppos: where to start
943 *
944 * Accepts only one cipso rule per write call.
945 * Returns number of bytes written or error code, as appropriate
946 */
smk_write_cipso(struct file * file,const char __user * buf,size_t count,loff_t * ppos)947 static ssize_t smk_write_cipso(struct file *file, const char __user *buf,
948 size_t count, loff_t *ppos)
949 {
950 return smk_set_cipso(file, buf, count, ppos, SMK_FIXED24_FMT);
951 }
952
953 static const struct file_operations smk_cipso_ops = {
954 .open = smk_open_cipso,
955 .read = seq_read,
956 .llseek = seq_lseek,
957 .write = smk_write_cipso,
958 .release = seq_release,
959 };
960
961 /*
962 * Seq_file read operations for /smack/cipso2
963 */
964
965 /*
966 * Print cipso labels in format:
967 * label level[/cat[,cat]]
968 */
cipso2_seq_show(struct seq_file * s,void * v)969 static int cipso2_seq_show(struct seq_file *s, void *v)
970 {
971 struct list_head *list = v;
972 struct smack_known *skp =
973 list_entry_rcu(list, struct smack_known, list);
974 struct netlbl_lsm_catmap *cmp = skp->smk_netlabel.attr.mls.cat;
975 char sep = '/';
976 int i;
977
978 seq_printf(s, "%s %3d", skp->smk_known, skp->smk_netlabel.attr.mls.lvl);
979
980 for (i = netlbl_catmap_walk(cmp, 0); i >= 0;
981 i = netlbl_catmap_walk(cmp, i + 1)) {
982 seq_printf(s, "%c%d", sep, i);
983 sep = ',';
984 }
985
986 seq_putc(s, '\n');
987
988 return 0;
989 }
990
991 static const struct seq_operations cipso2_seq_ops = {
992 .start = cipso_seq_start,
993 .next = cipso_seq_next,
994 .show = cipso2_seq_show,
995 .stop = smk_seq_stop,
996 };
997
998 /**
999 * smk_open_cipso2 - open() for /smack/cipso2
1000 * @inode: inode structure representing file
1001 * @file: "cipso2" file pointer
1002 *
1003 * Connect our cipso_seq_* operations with /smack/cipso2
1004 * file_operations
1005 */
smk_open_cipso2(struct inode * inode,struct file * file)1006 static int smk_open_cipso2(struct inode *inode, struct file *file)
1007 {
1008 return seq_open(file, &cipso2_seq_ops);
1009 }
1010
1011 /**
1012 * smk_write_cipso2 - write() for /smack/cipso2
1013 * @file: file pointer, not actually used
1014 * @buf: where to get the data from
1015 * @count: bytes sent
1016 * @ppos: where to start
1017 *
1018 * Accepts only one cipso rule per write call.
1019 * Returns number of bytes written or error code, as appropriate
1020 */
smk_write_cipso2(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1021 static ssize_t smk_write_cipso2(struct file *file, const char __user *buf,
1022 size_t count, loff_t *ppos)
1023 {
1024 return smk_set_cipso(file, buf, count, ppos, SMK_LONG_FMT);
1025 }
1026
1027 static const struct file_operations smk_cipso2_ops = {
1028 .open = smk_open_cipso2,
1029 .read = seq_read,
1030 .llseek = seq_lseek,
1031 .write = smk_write_cipso2,
1032 .release = seq_release,
1033 };
1034
1035 /*
1036 * Seq_file read operations for /smack/netlabel
1037 */
1038
net4addr_seq_start(struct seq_file * s,loff_t * pos)1039 static void *net4addr_seq_start(struct seq_file *s, loff_t *pos)
1040 {
1041 return smk_seq_start(s, pos, &smk_net4addr_list);
1042 }
1043
net4addr_seq_next(struct seq_file * s,void * v,loff_t * pos)1044 static void *net4addr_seq_next(struct seq_file *s, void *v, loff_t *pos)
1045 {
1046 return smk_seq_next(s, v, pos, &smk_net4addr_list);
1047 }
1048
1049 /*
1050 * Print host/label pairs
1051 */
net4addr_seq_show(struct seq_file * s,void * v)1052 static int net4addr_seq_show(struct seq_file *s, void *v)
1053 {
1054 struct list_head *list = v;
1055 struct smk_net4addr *skp =
1056 list_entry_rcu(list, struct smk_net4addr, list);
1057 char *kp = SMACK_CIPSO_OPTION;
1058
1059 if (skp->smk_label != NULL)
1060 kp = skp->smk_label->smk_known;
1061 seq_printf(s, "%pI4/%d %s\n", &skp->smk_host.s_addr,
1062 skp->smk_masks, kp);
1063
1064 return 0;
1065 }
1066
1067 static const struct seq_operations net4addr_seq_ops = {
1068 .start = net4addr_seq_start,
1069 .next = net4addr_seq_next,
1070 .show = net4addr_seq_show,
1071 .stop = smk_seq_stop,
1072 };
1073
1074 /**
1075 * smk_open_net4addr - open() for /smack/netlabel
1076 * @inode: inode structure representing file
1077 * @file: "netlabel" file pointer
1078 *
1079 * Connect our net4addr_seq_* operations with /smack/netlabel
1080 * file_operations
1081 */
smk_open_net4addr(struct inode * inode,struct file * file)1082 static int smk_open_net4addr(struct inode *inode, struct file *file)
1083 {
1084 return seq_open(file, &net4addr_seq_ops);
1085 }
1086
1087 /**
1088 * smk_net4addr_insert
1089 * @new : netlabel to insert
1090 *
1091 * This helper insert netlabel in the smack_net4addrs list
1092 * sorted by netmask length (longest to smallest)
1093 * locked by &smk_net4addr_lock in smk_write_net4addr
1094 *
1095 */
smk_net4addr_insert(struct smk_net4addr * new)1096 static void smk_net4addr_insert(struct smk_net4addr *new)
1097 {
1098 struct smk_net4addr *m;
1099 struct smk_net4addr *m_next;
1100
1101 if (list_empty(&smk_net4addr_list)) {
1102 list_add_rcu(&new->list, &smk_net4addr_list);
1103 return;
1104 }
1105
1106 m = list_entry_rcu(smk_net4addr_list.next,
1107 struct smk_net4addr, list);
1108
1109 /* the comparison '>' is a bit hacky, but works */
1110 if (new->smk_masks > m->smk_masks) {
1111 list_add_rcu(&new->list, &smk_net4addr_list);
1112 return;
1113 }
1114
1115 list_for_each_entry_rcu(m, &smk_net4addr_list, list) {
1116 if (list_is_last(&m->list, &smk_net4addr_list)) {
1117 list_add_rcu(&new->list, &m->list);
1118 return;
1119 }
1120 m_next = list_entry_rcu(m->list.next,
1121 struct smk_net4addr, list);
1122 if (new->smk_masks > m_next->smk_masks) {
1123 list_add_rcu(&new->list, &m->list);
1124 return;
1125 }
1126 }
1127 }
1128
1129
1130 /**
1131 * smk_write_net4addr - write() for /smack/netlabel
1132 * @file: file pointer, not actually used
1133 * @buf: where to get the data from
1134 * @count: bytes sent
1135 * @ppos: where to start
1136 *
1137 * Accepts only one net4addr per write call.
1138 * Returns number of bytes written or error code, as appropriate
1139 */
smk_write_net4addr(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1140 static ssize_t smk_write_net4addr(struct file *file, const char __user *buf,
1141 size_t count, loff_t *ppos)
1142 {
1143 struct smk_net4addr *snp;
1144 struct sockaddr_in newname;
1145 char *smack;
1146 struct smack_known *skp = NULL;
1147 char *data;
1148 char *host = (char *)&newname.sin_addr.s_addr;
1149 int rc;
1150 struct netlbl_audit audit_info;
1151 struct in_addr mask;
1152 unsigned int m;
1153 unsigned int masks;
1154 int found;
1155 u32 mask_bits = (1<<31);
1156 __be32 nsa;
1157 u32 temp_mask;
1158
1159 /*
1160 * Must have privilege.
1161 * No partial writes.
1162 * Enough data must be present.
1163 * "<addr/mask, as a.b.c.d/e><space><label>"
1164 * "<addr, as a.b.c.d><space><label>"
1165 */
1166 if (!smack_privileged(CAP_MAC_ADMIN))
1167 return -EPERM;
1168 if (*ppos != 0)
1169 return -EINVAL;
1170 if (count < SMK_NETLBLADDRMIN || count > PAGE_SIZE - 1)
1171 return -EINVAL;
1172
1173 data = memdup_user_nul(buf, count);
1174 if (IS_ERR(data))
1175 return PTR_ERR(data);
1176
1177 smack = kzalloc(count + 1, GFP_KERNEL);
1178 if (smack == NULL) {
1179 rc = -ENOMEM;
1180 goto free_data_out;
1181 }
1182
1183 rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd/%u %s",
1184 &host[0], &host[1], &host[2], &host[3], &masks, smack);
1185 if (rc != 6) {
1186 rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd %s",
1187 &host[0], &host[1], &host[2], &host[3], smack);
1188 if (rc != 5) {
1189 rc = -EINVAL;
1190 goto free_out;
1191 }
1192 m = BEBITS;
1193 masks = 32;
1194 }
1195 if (masks > BEBITS) {
1196 rc = -EINVAL;
1197 goto free_out;
1198 }
1199
1200 /*
1201 * If smack begins with '-', it is an option, don't import it
1202 */
1203 if (smack[0] != '-') {
1204 skp = smk_import_entry(smack, 0);
1205 if (IS_ERR(skp)) {
1206 rc = PTR_ERR(skp);
1207 goto free_out;
1208 }
1209 } else {
1210 /*
1211 * Only the -CIPSO option is supported for IPv4
1212 */
1213 if (strcmp(smack, SMACK_CIPSO_OPTION) != 0) {
1214 rc = -EINVAL;
1215 goto free_out;
1216 }
1217 }
1218
1219 for (m = masks, temp_mask = 0; m > 0; m--) {
1220 temp_mask |= mask_bits;
1221 mask_bits >>= 1;
1222 }
1223 mask.s_addr = cpu_to_be32(temp_mask);
1224
1225 newname.sin_addr.s_addr &= mask.s_addr;
1226 /*
1227 * Only allow one writer at a time. Writes should be
1228 * quite rare and small in any case.
1229 */
1230 mutex_lock(&smk_net4addr_lock);
1231
1232 nsa = newname.sin_addr.s_addr;
1233 /* try to find if the prefix is already in the list */
1234 found = 0;
1235 list_for_each_entry_rcu(snp, &smk_net4addr_list, list) {
1236 if (snp->smk_host.s_addr == nsa && snp->smk_masks == masks) {
1237 found = 1;
1238 break;
1239 }
1240 }
1241 smk_netlabel_audit_set(&audit_info);
1242
1243 if (found == 0) {
1244 snp = kzalloc(sizeof(*snp), GFP_KERNEL);
1245 if (snp == NULL)
1246 rc = -ENOMEM;
1247 else {
1248 rc = 0;
1249 snp->smk_host.s_addr = newname.sin_addr.s_addr;
1250 snp->smk_mask.s_addr = mask.s_addr;
1251 snp->smk_label = skp;
1252 snp->smk_masks = masks;
1253 smk_net4addr_insert(snp);
1254 }
1255 } else {
1256 /*
1257 * Delete the unlabeled entry, only if the previous label
1258 * wasn't the special CIPSO option
1259 */
1260 if (snp->smk_label != NULL)
1261 rc = netlbl_cfg_unlbl_static_del(&init_net, NULL,
1262 &snp->smk_host, &snp->smk_mask,
1263 PF_INET, &audit_info);
1264 else
1265 rc = 0;
1266 snp->smk_label = skp;
1267 }
1268
1269 /*
1270 * Now tell netlabel about the single label nature of
1271 * this host so that incoming packets get labeled.
1272 * but only if we didn't get the special CIPSO option
1273 */
1274 if (rc == 0 && skp != NULL)
1275 rc = netlbl_cfg_unlbl_static_add(&init_net, NULL,
1276 &snp->smk_host, &snp->smk_mask, PF_INET,
1277 snp->smk_label->smk_secid, &audit_info);
1278
1279 if (rc == 0)
1280 rc = count;
1281
1282 mutex_unlock(&smk_net4addr_lock);
1283
1284 free_out:
1285 kfree(smack);
1286 free_data_out:
1287 kfree(data);
1288
1289 return rc;
1290 }
1291
1292 static const struct file_operations smk_net4addr_ops = {
1293 .open = smk_open_net4addr,
1294 .read = seq_read,
1295 .llseek = seq_lseek,
1296 .write = smk_write_net4addr,
1297 .release = seq_release,
1298 };
1299
1300 #if IS_ENABLED(CONFIG_IPV6)
1301 /*
1302 * Seq_file read operations for /smack/netlabel6
1303 */
1304
net6addr_seq_start(struct seq_file * s,loff_t * pos)1305 static void *net6addr_seq_start(struct seq_file *s, loff_t *pos)
1306 {
1307 return smk_seq_start(s, pos, &smk_net6addr_list);
1308 }
1309
net6addr_seq_next(struct seq_file * s,void * v,loff_t * pos)1310 static void *net6addr_seq_next(struct seq_file *s, void *v, loff_t *pos)
1311 {
1312 return smk_seq_next(s, v, pos, &smk_net6addr_list);
1313 }
1314
1315 /*
1316 * Print host/label pairs
1317 */
net6addr_seq_show(struct seq_file * s,void * v)1318 static int net6addr_seq_show(struct seq_file *s, void *v)
1319 {
1320 struct list_head *list = v;
1321 struct smk_net6addr *skp =
1322 list_entry(list, struct smk_net6addr, list);
1323
1324 if (skp->smk_label != NULL)
1325 seq_printf(s, "%pI6/%d %s\n", &skp->smk_host, skp->smk_masks,
1326 skp->smk_label->smk_known);
1327
1328 return 0;
1329 }
1330
1331 static const struct seq_operations net6addr_seq_ops = {
1332 .start = net6addr_seq_start,
1333 .next = net6addr_seq_next,
1334 .show = net6addr_seq_show,
1335 .stop = smk_seq_stop,
1336 };
1337
1338 /**
1339 * smk_open_net6addr - open() for /smack/netlabel
1340 * @inode: inode structure representing file
1341 * @file: "netlabel" file pointer
1342 *
1343 * Connect our net6addr_seq_* operations with /smack/netlabel
1344 * file_operations
1345 */
smk_open_net6addr(struct inode * inode,struct file * file)1346 static int smk_open_net6addr(struct inode *inode, struct file *file)
1347 {
1348 return seq_open(file, &net6addr_seq_ops);
1349 }
1350
1351 /**
1352 * smk_net6addr_insert
1353 * @new : entry to insert
1354 *
1355 * This inserts an entry in the smack_net6addrs list
1356 * sorted by netmask length (longest to smallest)
1357 * locked by &smk_net6addr_lock in smk_write_net6addr
1358 *
1359 */
smk_net6addr_insert(struct smk_net6addr * new)1360 static void smk_net6addr_insert(struct smk_net6addr *new)
1361 {
1362 struct smk_net6addr *m_next;
1363 struct smk_net6addr *m;
1364
1365 if (list_empty(&smk_net6addr_list)) {
1366 list_add_rcu(&new->list, &smk_net6addr_list);
1367 return;
1368 }
1369
1370 m = list_entry_rcu(smk_net6addr_list.next,
1371 struct smk_net6addr, list);
1372
1373 if (new->smk_masks > m->smk_masks) {
1374 list_add_rcu(&new->list, &smk_net6addr_list);
1375 return;
1376 }
1377
1378 list_for_each_entry_rcu(m, &smk_net6addr_list, list) {
1379 if (list_is_last(&m->list, &smk_net6addr_list)) {
1380 list_add_rcu(&new->list, &m->list);
1381 return;
1382 }
1383 m_next = list_entry_rcu(m->list.next,
1384 struct smk_net6addr, list);
1385 if (new->smk_masks > m_next->smk_masks) {
1386 list_add_rcu(&new->list, &m->list);
1387 return;
1388 }
1389 }
1390 }
1391
1392
1393 /**
1394 * smk_write_net6addr - write() for /smack/netlabel
1395 * @file: file pointer, not actually used
1396 * @buf: where to get the data from
1397 * @count: bytes sent
1398 * @ppos: where to start
1399 *
1400 * Accepts only one net6addr per write call.
1401 * Returns number of bytes written or error code, as appropriate
1402 */
smk_write_net6addr(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1403 static ssize_t smk_write_net6addr(struct file *file, const char __user *buf,
1404 size_t count, loff_t *ppos)
1405 {
1406 struct smk_net6addr *snp;
1407 struct in6_addr newname;
1408 struct in6_addr fullmask;
1409 struct smack_known *skp = NULL;
1410 char *smack;
1411 char *data;
1412 int rc = 0;
1413 int found = 0;
1414 int i;
1415 unsigned int scanned[8];
1416 unsigned int m;
1417 unsigned int mask = 128;
1418
1419 /*
1420 * Must have privilege.
1421 * No partial writes.
1422 * Enough data must be present.
1423 * "<addr/mask, as a:b:c:d:e:f:g:h/e><space><label>"
1424 * "<addr, as a:b:c:d:e:f:g:h><space><label>"
1425 */
1426 if (!smack_privileged(CAP_MAC_ADMIN))
1427 return -EPERM;
1428 if (*ppos != 0)
1429 return -EINVAL;
1430 if (count < SMK_NETLBLADDRMIN || count > PAGE_SIZE - 1)
1431 return -EINVAL;
1432
1433 data = memdup_user_nul(buf, count);
1434 if (IS_ERR(data))
1435 return PTR_ERR(data);
1436
1437 smack = kzalloc(count + 1, GFP_KERNEL);
1438 if (smack == NULL) {
1439 rc = -ENOMEM;
1440 goto free_data_out;
1441 }
1442
1443 i = sscanf(data, "%x:%x:%x:%x:%x:%x:%x:%x/%u %s",
1444 &scanned[0], &scanned[1], &scanned[2], &scanned[3],
1445 &scanned[4], &scanned[5], &scanned[6], &scanned[7],
1446 &mask, smack);
1447 if (i != 10) {
1448 i = sscanf(data, "%x:%x:%x:%x:%x:%x:%x:%x %s",
1449 &scanned[0], &scanned[1], &scanned[2],
1450 &scanned[3], &scanned[4], &scanned[5],
1451 &scanned[6], &scanned[7], smack);
1452 if (i != 9) {
1453 rc = -EINVAL;
1454 goto free_out;
1455 }
1456 }
1457 if (mask > 128) {
1458 rc = -EINVAL;
1459 goto free_out;
1460 }
1461 for (i = 0; i < 8; i++) {
1462 if (scanned[i] > 0xffff) {
1463 rc = -EINVAL;
1464 goto free_out;
1465 }
1466 newname.s6_addr16[i] = htons(scanned[i]);
1467 }
1468
1469 /*
1470 * If smack begins with '-', it is an option, don't import it
1471 */
1472 if (smack[0] != '-') {
1473 skp = smk_import_entry(smack, 0);
1474 if (IS_ERR(skp)) {
1475 rc = PTR_ERR(skp);
1476 goto free_out;
1477 }
1478 } else {
1479 /*
1480 * Only -DELETE is supported for IPv6
1481 */
1482 if (strcmp(smack, SMACK_DELETE_OPTION) != 0) {
1483 rc = -EINVAL;
1484 goto free_out;
1485 }
1486 }
1487
1488 for (i = 0, m = mask; i < 8; i++) {
1489 if (m >= 16) {
1490 fullmask.s6_addr16[i] = 0xffff;
1491 m -= 16;
1492 } else if (m > 0) {
1493 fullmask.s6_addr16[i] = (1 << m) - 1;
1494 m = 0;
1495 } else
1496 fullmask.s6_addr16[i] = 0;
1497 newname.s6_addr16[i] &= fullmask.s6_addr16[i];
1498 }
1499
1500 /*
1501 * Only allow one writer at a time. Writes should be
1502 * quite rare and small in any case.
1503 */
1504 mutex_lock(&smk_net6addr_lock);
1505 /*
1506 * Try to find the prefix in the list
1507 */
1508 list_for_each_entry_rcu(snp, &smk_net6addr_list, list) {
1509 if (mask != snp->smk_masks)
1510 continue;
1511 for (found = 1, i = 0; i < 8; i++) {
1512 if (newname.s6_addr16[i] !=
1513 snp->smk_host.s6_addr16[i]) {
1514 found = 0;
1515 break;
1516 }
1517 }
1518 if (found == 1)
1519 break;
1520 }
1521 if (found == 0) {
1522 snp = kzalloc(sizeof(*snp), GFP_KERNEL);
1523 if (snp == NULL)
1524 rc = -ENOMEM;
1525 else {
1526 snp->smk_host = newname;
1527 snp->smk_mask = fullmask;
1528 snp->smk_masks = mask;
1529 snp->smk_label = skp;
1530 smk_net6addr_insert(snp);
1531 }
1532 } else {
1533 snp->smk_label = skp;
1534 }
1535
1536 if (rc == 0)
1537 rc = count;
1538
1539 mutex_unlock(&smk_net6addr_lock);
1540
1541 free_out:
1542 kfree(smack);
1543 free_data_out:
1544 kfree(data);
1545
1546 return rc;
1547 }
1548
1549 static const struct file_operations smk_net6addr_ops = {
1550 .open = smk_open_net6addr,
1551 .read = seq_read,
1552 .llseek = seq_lseek,
1553 .write = smk_write_net6addr,
1554 .release = seq_release,
1555 };
1556 #endif /* CONFIG_IPV6 */
1557
1558 /**
1559 * smk_read_doi - read() for /smack/doi
1560 * @filp: file pointer, not actually used
1561 * @buf: where to put the result
1562 * @count: maximum to send along
1563 * @ppos: where to start
1564 *
1565 * Returns number of bytes read or error code, as appropriate
1566 */
smk_read_doi(struct file * filp,char __user * buf,size_t count,loff_t * ppos)1567 static ssize_t smk_read_doi(struct file *filp, char __user *buf,
1568 size_t count, loff_t *ppos)
1569 {
1570 char temp[80];
1571 ssize_t rc;
1572
1573 if (*ppos != 0)
1574 return 0;
1575
1576 sprintf(temp, "%d", smk_cipso_doi_value);
1577 rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
1578
1579 return rc;
1580 }
1581
1582 /**
1583 * smk_write_doi - write() for /smack/doi
1584 * @file: file pointer, not actually used
1585 * @buf: where to get the data from
1586 * @count: bytes sent
1587 * @ppos: where to start
1588 *
1589 * Returns number of bytes written or error code, as appropriate
1590 */
smk_write_doi(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1591 static ssize_t smk_write_doi(struct file *file, const char __user *buf,
1592 size_t count, loff_t *ppos)
1593 {
1594 char temp[80];
1595 int i;
1596
1597 if (!smack_privileged(CAP_MAC_ADMIN))
1598 return -EPERM;
1599
1600 if (count >= sizeof(temp) || count == 0)
1601 return -EINVAL;
1602
1603 if (copy_from_user(temp, buf, count) != 0)
1604 return -EFAULT;
1605
1606 temp[count] = '\0';
1607
1608 if (sscanf(temp, "%d", &i) != 1)
1609 return -EINVAL;
1610
1611 smk_cipso_doi_value = i;
1612
1613 smk_cipso_doi();
1614
1615 return count;
1616 }
1617
1618 static const struct file_operations smk_doi_ops = {
1619 .read = smk_read_doi,
1620 .write = smk_write_doi,
1621 .llseek = default_llseek,
1622 };
1623
1624 /**
1625 * smk_read_direct - read() for /smack/direct
1626 * @filp: file pointer, not actually used
1627 * @buf: where to put the result
1628 * @count: maximum to send along
1629 * @ppos: where to start
1630 *
1631 * Returns number of bytes read or error code, as appropriate
1632 */
smk_read_direct(struct file * filp,char __user * buf,size_t count,loff_t * ppos)1633 static ssize_t smk_read_direct(struct file *filp, char __user *buf,
1634 size_t count, loff_t *ppos)
1635 {
1636 char temp[80];
1637 ssize_t rc;
1638
1639 if (*ppos != 0)
1640 return 0;
1641
1642 sprintf(temp, "%d", smack_cipso_direct);
1643 rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
1644
1645 return rc;
1646 }
1647
1648 /**
1649 * smk_write_direct - write() for /smack/direct
1650 * @file: file pointer, not actually used
1651 * @buf: where to get the data from
1652 * @count: bytes sent
1653 * @ppos: where to start
1654 *
1655 * Returns number of bytes written or error code, as appropriate
1656 */
smk_write_direct(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1657 static ssize_t smk_write_direct(struct file *file, const char __user *buf,
1658 size_t count, loff_t *ppos)
1659 {
1660 struct smack_known *skp;
1661 char temp[80];
1662 int i;
1663
1664 if (!smack_privileged(CAP_MAC_ADMIN))
1665 return -EPERM;
1666
1667 if (count >= sizeof(temp) || count == 0)
1668 return -EINVAL;
1669
1670 if (copy_from_user(temp, buf, count) != 0)
1671 return -EFAULT;
1672
1673 temp[count] = '\0';
1674
1675 if (sscanf(temp, "%d", &i) != 1)
1676 return -EINVAL;
1677
1678 /*
1679 * Don't do anything if the value hasn't actually changed.
1680 * If it is changing reset the level on entries that were
1681 * set up to be direct when they were created.
1682 */
1683 if (smack_cipso_direct != i) {
1684 mutex_lock(&smack_known_lock);
1685 list_for_each_entry_rcu(skp, &smack_known_list, list)
1686 if (skp->smk_netlabel.attr.mls.lvl ==
1687 smack_cipso_direct)
1688 skp->smk_netlabel.attr.mls.lvl = i;
1689 smack_cipso_direct = i;
1690 mutex_unlock(&smack_known_lock);
1691 }
1692
1693 return count;
1694 }
1695
1696 static const struct file_operations smk_direct_ops = {
1697 .read = smk_read_direct,
1698 .write = smk_write_direct,
1699 .llseek = default_llseek,
1700 };
1701
1702 /**
1703 * smk_read_mapped - read() for /smack/mapped
1704 * @filp: file pointer, not actually used
1705 * @buf: where to put the result
1706 * @count: maximum to send along
1707 * @ppos: where to start
1708 *
1709 * Returns number of bytes read or error code, as appropriate
1710 */
smk_read_mapped(struct file * filp,char __user * buf,size_t count,loff_t * ppos)1711 static ssize_t smk_read_mapped(struct file *filp, char __user *buf,
1712 size_t count, loff_t *ppos)
1713 {
1714 char temp[80];
1715 ssize_t rc;
1716
1717 if (*ppos != 0)
1718 return 0;
1719
1720 sprintf(temp, "%d", smack_cipso_mapped);
1721 rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
1722
1723 return rc;
1724 }
1725
1726 /**
1727 * smk_write_mapped - write() for /smack/mapped
1728 * @file: file pointer, not actually used
1729 * @buf: where to get the data from
1730 * @count: bytes sent
1731 * @ppos: where to start
1732 *
1733 * Returns number of bytes written or error code, as appropriate
1734 */
smk_write_mapped(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1735 static ssize_t smk_write_mapped(struct file *file, const char __user *buf,
1736 size_t count, loff_t *ppos)
1737 {
1738 struct smack_known *skp;
1739 char temp[80];
1740 int i;
1741
1742 if (!smack_privileged(CAP_MAC_ADMIN))
1743 return -EPERM;
1744
1745 if (count >= sizeof(temp) || count == 0)
1746 return -EINVAL;
1747
1748 if (copy_from_user(temp, buf, count) != 0)
1749 return -EFAULT;
1750
1751 temp[count] = '\0';
1752
1753 if (sscanf(temp, "%d", &i) != 1)
1754 return -EINVAL;
1755
1756 /*
1757 * Don't do anything if the value hasn't actually changed.
1758 * If it is changing reset the level on entries that were
1759 * set up to be mapped when they were created.
1760 */
1761 if (smack_cipso_mapped != i) {
1762 mutex_lock(&smack_known_lock);
1763 list_for_each_entry_rcu(skp, &smack_known_list, list)
1764 if (skp->smk_netlabel.attr.mls.lvl ==
1765 smack_cipso_mapped)
1766 skp->smk_netlabel.attr.mls.lvl = i;
1767 smack_cipso_mapped = i;
1768 mutex_unlock(&smack_known_lock);
1769 }
1770
1771 return count;
1772 }
1773
1774 static const struct file_operations smk_mapped_ops = {
1775 .read = smk_read_mapped,
1776 .write = smk_write_mapped,
1777 .llseek = default_llseek,
1778 };
1779
1780 /**
1781 * smk_read_ambient - read() for /smack/ambient
1782 * @filp: file pointer, not actually used
1783 * @buf: where to put the result
1784 * @cn: maximum to send along
1785 * @ppos: where to start
1786 *
1787 * Returns number of bytes read or error code, as appropriate
1788 */
smk_read_ambient(struct file * filp,char __user * buf,size_t cn,loff_t * ppos)1789 static ssize_t smk_read_ambient(struct file *filp, char __user *buf,
1790 size_t cn, loff_t *ppos)
1791 {
1792 ssize_t rc;
1793 int asize;
1794
1795 if (*ppos != 0)
1796 return 0;
1797 /*
1798 * Being careful to avoid a problem in the case where
1799 * smack_net_ambient gets changed in midstream.
1800 */
1801 mutex_lock(&smack_ambient_lock);
1802
1803 asize = strlen(smack_net_ambient->smk_known) + 1;
1804
1805 if (cn >= asize)
1806 rc = simple_read_from_buffer(buf, cn, ppos,
1807 smack_net_ambient->smk_known,
1808 asize);
1809 else
1810 rc = -EINVAL;
1811
1812 mutex_unlock(&smack_ambient_lock);
1813
1814 return rc;
1815 }
1816
1817 /**
1818 * smk_write_ambient - write() for /smack/ambient
1819 * @file: file pointer, not actually used
1820 * @buf: where to get the data from
1821 * @count: bytes sent
1822 * @ppos: where to start
1823 *
1824 * Returns number of bytes written or error code, as appropriate
1825 */
smk_write_ambient(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1826 static ssize_t smk_write_ambient(struct file *file, const char __user *buf,
1827 size_t count, loff_t *ppos)
1828 {
1829 struct smack_known *skp;
1830 char *oldambient;
1831 char *data;
1832 int rc = count;
1833
1834 if (!smack_privileged(CAP_MAC_ADMIN))
1835 return -EPERM;
1836
1837 /* Enough data must be present */
1838 if (count == 0 || count > PAGE_SIZE)
1839 return -EINVAL;
1840
1841 data = memdup_user_nul(buf, count);
1842 if (IS_ERR(data))
1843 return PTR_ERR(data);
1844
1845 skp = smk_import_entry(data, count);
1846 if (IS_ERR(skp)) {
1847 rc = PTR_ERR(skp);
1848 goto out;
1849 }
1850
1851 mutex_lock(&smack_ambient_lock);
1852
1853 oldambient = smack_net_ambient->smk_known;
1854 smack_net_ambient = skp;
1855 smk_unlbl_ambient(oldambient);
1856
1857 mutex_unlock(&smack_ambient_lock);
1858
1859 out:
1860 kfree(data);
1861 return rc;
1862 }
1863
1864 static const struct file_operations smk_ambient_ops = {
1865 .read = smk_read_ambient,
1866 .write = smk_write_ambient,
1867 .llseek = default_llseek,
1868 };
1869
1870 /*
1871 * Seq_file operations for /smack/onlycap
1872 */
onlycap_seq_start(struct seq_file * s,loff_t * pos)1873 static void *onlycap_seq_start(struct seq_file *s, loff_t *pos)
1874 {
1875 return smk_seq_start(s, pos, &smack_onlycap_list);
1876 }
1877
onlycap_seq_next(struct seq_file * s,void * v,loff_t * pos)1878 static void *onlycap_seq_next(struct seq_file *s, void *v, loff_t *pos)
1879 {
1880 return smk_seq_next(s, v, pos, &smack_onlycap_list);
1881 }
1882
onlycap_seq_show(struct seq_file * s,void * v)1883 static int onlycap_seq_show(struct seq_file *s, void *v)
1884 {
1885 struct list_head *list = v;
1886 struct smack_known_list_elem *sklep =
1887 list_entry_rcu(list, struct smack_known_list_elem, list);
1888
1889 seq_puts(s, sklep->smk_label->smk_known);
1890 seq_putc(s, ' ');
1891
1892 return 0;
1893 }
1894
1895 static const struct seq_operations onlycap_seq_ops = {
1896 .start = onlycap_seq_start,
1897 .next = onlycap_seq_next,
1898 .show = onlycap_seq_show,
1899 .stop = smk_seq_stop,
1900 };
1901
smk_open_onlycap(struct inode * inode,struct file * file)1902 static int smk_open_onlycap(struct inode *inode, struct file *file)
1903 {
1904 return seq_open(file, &onlycap_seq_ops);
1905 }
1906
1907 /**
1908 * smk_list_swap_rcu - swap public list with a private one in RCU-safe way
1909 * The caller must hold appropriate mutex to prevent concurrent modifications
1910 * to the public list.
1911 * Private list is assumed to be not accessible to other threads yet.
1912 *
1913 * @public: public list
1914 * @private: private list
1915 */
smk_list_swap_rcu(struct list_head * public,struct list_head * private)1916 static void smk_list_swap_rcu(struct list_head *public,
1917 struct list_head *private)
1918 {
1919 struct list_head *first, *last;
1920
1921 if (list_empty(public)) {
1922 list_splice_init_rcu(private, public, synchronize_rcu);
1923 } else {
1924 /* Remember public list before replacing it */
1925 first = public->next;
1926 last = public->prev;
1927
1928 /* Publish private list in place of public in RCU-safe way */
1929 private->prev->next = public;
1930 private->next->prev = public;
1931 rcu_assign_pointer(public->next, private->next);
1932 public->prev = private->prev;
1933
1934 synchronize_rcu();
1935
1936 /* When all readers are done with the old public list,
1937 * attach it in place of private */
1938 private->next = first;
1939 private->prev = last;
1940 first->prev = private;
1941 last->next = private;
1942 }
1943 }
1944
1945 /**
1946 * smk_parse_label_list - parse list of Smack labels, separated by spaces
1947 *
1948 * @data: the string to parse
1949 * @list: destination list
1950 *
1951 * Returns zero on success or error code, as appropriate
1952 */
smk_parse_label_list(char * data,struct list_head * list)1953 static int smk_parse_label_list(char *data, struct list_head *list)
1954 {
1955 char *tok;
1956 struct smack_known *skp;
1957 struct smack_known_list_elem *sklep;
1958
1959 while ((tok = strsep(&data, " ")) != NULL) {
1960 if (!*tok)
1961 continue;
1962
1963 skp = smk_import_entry(tok, 0);
1964 if (IS_ERR(skp))
1965 return PTR_ERR(skp);
1966
1967 sklep = kzalloc(sizeof(*sklep), GFP_KERNEL);
1968 if (sklep == NULL)
1969 return -ENOMEM;
1970
1971 sklep->smk_label = skp;
1972 list_add(&sklep->list, list);
1973 }
1974
1975 return 0;
1976 }
1977
1978 /**
1979 * smk_destroy_label_list - destroy a list of smack_known_list_elem
1980 * @list: header pointer of the list to destroy
1981 */
smk_destroy_label_list(struct list_head * list)1982 void smk_destroy_label_list(struct list_head *list)
1983 {
1984 struct smack_known_list_elem *sklep;
1985 struct smack_known_list_elem *sklep2;
1986
1987 list_for_each_entry_safe(sklep, sklep2, list, list)
1988 kfree(sklep);
1989
1990 INIT_LIST_HEAD(list);
1991 }
1992
1993 /**
1994 * smk_write_onlycap - write() for smackfs/onlycap
1995 * @file: file pointer, not actually used
1996 * @buf: where to get the data from
1997 * @count: bytes sent
1998 * @ppos: where to start
1999 *
2000 * Returns number of bytes written or error code, as appropriate
2001 */
smk_write_onlycap(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2002 static ssize_t smk_write_onlycap(struct file *file, const char __user *buf,
2003 size_t count, loff_t *ppos)
2004 {
2005 char *data;
2006 LIST_HEAD(list_tmp);
2007 int rc;
2008
2009 if (!smack_privileged(CAP_MAC_ADMIN))
2010 return -EPERM;
2011
2012 if (count > PAGE_SIZE)
2013 return -EINVAL;
2014
2015 data = memdup_user_nul(buf, count);
2016 if (IS_ERR(data))
2017 return PTR_ERR(data);
2018
2019 rc = smk_parse_label_list(data, &list_tmp);
2020 kfree(data);
2021
2022 /*
2023 * Clear the smack_onlycap on invalid label errors. This means
2024 * that we can pass a null string to unset the onlycap value.
2025 *
2026 * Importing will also reject a label beginning with '-',
2027 * so "-usecapabilities" will also work.
2028 *
2029 * But do so only on invalid label, not on system errors.
2030 * The invalid label must be first to count as clearing attempt.
2031 */
2032 if (!rc || (rc == -EINVAL && list_empty(&list_tmp))) {
2033 mutex_lock(&smack_onlycap_lock);
2034 smk_list_swap_rcu(&smack_onlycap_list, &list_tmp);
2035 mutex_unlock(&smack_onlycap_lock);
2036 rc = count;
2037 }
2038
2039 smk_destroy_label_list(&list_tmp);
2040
2041 return rc;
2042 }
2043
2044 static const struct file_operations smk_onlycap_ops = {
2045 .open = smk_open_onlycap,
2046 .read = seq_read,
2047 .write = smk_write_onlycap,
2048 .llseek = seq_lseek,
2049 .release = seq_release,
2050 };
2051
2052 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
2053 /**
2054 * smk_read_unconfined - read() for smackfs/unconfined
2055 * @filp: file pointer, not actually used
2056 * @buf: where to put the result
2057 * @cn: maximum to send along
2058 * @ppos: where to start
2059 *
2060 * Returns number of bytes read or error code, as appropriate
2061 */
smk_read_unconfined(struct file * filp,char __user * buf,size_t cn,loff_t * ppos)2062 static ssize_t smk_read_unconfined(struct file *filp, char __user *buf,
2063 size_t cn, loff_t *ppos)
2064 {
2065 char *smack = "";
2066 ssize_t rc = -EINVAL;
2067 int asize;
2068
2069 if (*ppos != 0)
2070 return 0;
2071
2072 if (smack_unconfined != NULL)
2073 smack = smack_unconfined->smk_known;
2074
2075 asize = strlen(smack) + 1;
2076
2077 if (cn >= asize)
2078 rc = simple_read_from_buffer(buf, cn, ppos, smack, asize);
2079
2080 return rc;
2081 }
2082
2083 /**
2084 * smk_write_unconfined - write() for smackfs/unconfined
2085 * @file: file pointer, not actually used
2086 * @buf: where to get the data from
2087 * @count: bytes sent
2088 * @ppos: where to start
2089 *
2090 * Returns number of bytes written or error code, as appropriate
2091 */
smk_write_unconfined(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2092 static ssize_t smk_write_unconfined(struct file *file, const char __user *buf,
2093 size_t count, loff_t *ppos)
2094 {
2095 char *data;
2096 struct smack_known *skp;
2097 int rc = count;
2098
2099 if (!smack_privileged(CAP_MAC_ADMIN))
2100 return -EPERM;
2101
2102 if (count > PAGE_SIZE)
2103 return -EINVAL;
2104
2105 data = memdup_user_nul(buf, count);
2106 if (IS_ERR(data))
2107 return PTR_ERR(data);
2108
2109 /*
2110 * Clear the smack_unconfined on invalid label errors. This means
2111 * that we can pass a null string to unset the unconfined value.
2112 *
2113 * Importing will also reject a label beginning with '-',
2114 * so "-confine" will also work.
2115 *
2116 * But do so only on invalid label, not on system errors.
2117 */
2118 skp = smk_import_entry(data, count);
2119 if (PTR_ERR(skp) == -EINVAL)
2120 skp = NULL;
2121 else if (IS_ERR(skp)) {
2122 rc = PTR_ERR(skp);
2123 goto freeout;
2124 }
2125
2126 smack_unconfined = skp;
2127
2128 freeout:
2129 kfree(data);
2130 return rc;
2131 }
2132
2133 static const struct file_operations smk_unconfined_ops = {
2134 .read = smk_read_unconfined,
2135 .write = smk_write_unconfined,
2136 .llseek = default_llseek,
2137 };
2138 #endif /* CONFIG_SECURITY_SMACK_BRINGUP */
2139
2140 /**
2141 * smk_read_logging - read() for /smack/logging
2142 * @filp: file pointer, not actually used
2143 * @buf: where to put the result
2144 * @count: maximum to send along
2145 * @ppos: where to start
2146 *
2147 * Returns number of bytes read or error code, as appropriate
2148 */
smk_read_logging(struct file * filp,char __user * buf,size_t count,loff_t * ppos)2149 static ssize_t smk_read_logging(struct file *filp, char __user *buf,
2150 size_t count, loff_t *ppos)
2151 {
2152 char temp[32];
2153 ssize_t rc;
2154
2155 if (*ppos != 0)
2156 return 0;
2157
2158 sprintf(temp, "%d\n", log_policy);
2159 rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
2160 return rc;
2161 }
2162
2163 /**
2164 * smk_write_logging - write() for /smack/logging
2165 * @file: file pointer, not actually used
2166 * @buf: where to get the data from
2167 * @count: bytes sent
2168 * @ppos: where to start
2169 *
2170 * Returns number of bytes written or error code, as appropriate
2171 */
smk_write_logging(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2172 static ssize_t smk_write_logging(struct file *file, const char __user *buf,
2173 size_t count, loff_t *ppos)
2174 {
2175 char temp[32];
2176 int i;
2177
2178 if (!smack_privileged(CAP_MAC_ADMIN))
2179 return -EPERM;
2180
2181 if (count >= sizeof(temp) || count == 0)
2182 return -EINVAL;
2183
2184 if (copy_from_user(temp, buf, count) != 0)
2185 return -EFAULT;
2186
2187 temp[count] = '\0';
2188
2189 if (sscanf(temp, "%d", &i) != 1)
2190 return -EINVAL;
2191 if (i < 0 || i > 3)
2192 return -EINVAL;
2193 log_policy = i;
2194 return count;
2195 }
2196
2197
2198
2199 static const struct file_operations smk_logging_ops = {
2200 .read = smk_read_logging,
2201 .write = smk_write_logging,
2202 .llseek = default_llseek,
2203 };
2204
2205 /*
2206 * Seq_file read operations for /smack/load-self
2207 */
2208
load_self_seq_start(struct seq_file * s,loff_t * pos)2209 static void *load_self_seq_start(struct seq_file *s, loff_t *pos)
2210 {
2211 struct task_smack *tsp = smack_cred(current_cred());
2212
2213 return smk_seq_start(s, pos, &tsp->smk_rules);
2214 }
2215
load_self_seq_next(struct seq_file * s,void * v,loff_t * pos)2216 static void *load_self_seq_next(struct seq_file *s, void *v, loff_t *pos)
2217 {
2218 struct task_smack *tsp = smack_cred(current_cred());
2219
2220 return smk_seq_next(s, v, pos, &tsp->smk_rules);
2221 }
2222
load_self_seq_show(struct seq_file * s,void * v)2223 static int load_self_seq_show(struct seq_file *s, void *v)
2224 {
2225 struct list_head *list = v;
2226 struct smack_rule *srp =
2227 list_entry_rcu(list, struct smack_rule, list);
2228
2229 smk_rule_show(s, srp, SMK_LABELLEN);
2230
2231 return 0;
2232 }
2233
2234 static const struct seq_operations load_self_seq_ops = {
2235 .start = load_self_seq_start,
2236 .next = load_self_seq_next,
2237 .show = load_self_seq_show,
2238 .stop = smk_seq_stop,
2239 };
2240
2241
2242 /**
2243 * smk_open_load_self - open() for /smack/load-self2
2244 * @inode: inode structure representing file
2245 * @file: "load" file pointer
2246 *
2247 * For reading, use load_seq_* seq_file reading operations.
2248 */
smk_open_load_self(struct inode * inode,struct file * file)2249 static int smk_open_load_self(struct inode *inode, struct file *file)
2250 {
2251 return seq_open(file, &load_self_seq_ops);
2252 }
2253
2254 /**
2255 * smk_write_load_self - write() for /smack/load-self
2256 * @file: file pointer, not actually used
2257 * @buf: where to get the data from
2258 * @count: bytes sent
2259 * @ppos: where to start - must be 0
2260 *
2261 */
smk_write_load_self(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2262 static ssize_t smk_write_load_self(struct file *file, const char __user *buf,
2263 size_t count, loff_t *ppos)
2264 {
2265 struct task_smack *tsp = smack_cred(current_cred());
2266
2267 return smk_write_rules_list(file, buf, count, ppos, &tsp->smk_rules,
2268 &tsp->smk_rules_lock, SMK_FIXED24_FMT);
2269 }
2270
2271 static const struct file_operations smk_load_self_ops = {
2272 .open = smk_open_load_self,
2273 .read = seq_read,
2274 .llseek = seq_lseek,
2275 .write = smk_write_load_self,
2276 .release = seq_release,
2277 };
2278
2279 /**
2280 * smk_user_access - handle access check transaction
2281 * @file: file pointer
2282 * @buf: data from user space
2283 * @count: bytes sent
2284 * @ppos: where to start - must be 0
2285 * @format: /smack/load or /smack/load2 or /smack/change-rule format.
2286 */
smk_user_access(struct file * file,const char __user * buf,size_t count,loff_t * ppos,int format)2287 static ssize_t smk_user_access(struct file *file, const char __user *buf,
2288 size_t count, loff_t *ppos, int format)
2289 {
2290 struct smack_parsed_rule rule;
2291 char *data;
2292 int res;
2293
2294 data = simple_transaction_get(file, buf, count);
2295 if (IS_ERR(data))
2296 return PTR_ERR(data);
2297
2298 if (format == SMK_FIXED24_FMT) {
2299 if (count < SMK_LOADLEN)
2300 return -EINVAL;
2301 res = smk_parse_rule(data, &rule, 0);
2302 } else {
2303 /*
2304 * simple_transaction_get() returns null-terminated data
2305 */
2306 res = smk_parse_long_rule(data, &rule, 0, 3);
2307 }
2308
2309 if (res >= 0)
2310 res = smk_access(rule.smk_subject, rule.smk_object,
2311 rule.smk_access1, NULL);
2312 else if (res != -ENOENT)
2313 return res;
2314
2315 /*
2316 * smk_access() can return a value > 0 in the "bringup" case.
2317 */
2318 data[0] = res >= 0 ? '1' : '0';
2319 data[1] = '\0';
2320
2321 simple_transaction_set(file, 2);
2322
2323 if (format == SMK_FIXED24_FMT)
2324 return SMK_LOADLEN;
2325 return count;
2326 }
2327
2328 /**
2329 * smk_write_access - handle access check transaction
2330 * @file: file pointer
2331 * @buf: data from user space
2332 * @count: bytes sent
2333 * @ppos: where to start - must be 0
2334 */
smk_write_access(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2335 static ssize_t smk_write_access(struct file *file, const char __user *buf,
2336 size_t count, loff_t *ppos)
2337 {
2338 return smk_user_access(file, buf, count, ppos, SMK_FIXED24_FMT);
2339 }
2340
2341 static const struct file_operations smk_access_ops = {
2342 .write = smk_write_access,
2343 .read = simple_transaction_read,
2344 .release = simple_transaction_release,
2345 .llseek = generic_file_llseek,
2346 };
2347
2348
2349 /*
2350 * Seq_file read operations for /smack/load2
2351 */
2352
load2_seq_show(struct seq_file * s,void * v)2353 static int load2_seq_show(struct seq_file *s, void *v)
2354 {
2355 struct list_head *list = v;
2356 struct smack_rule *srp;
2357 struct smack_known *skp =
2358 list_entry_rcu(list, struct smack_known, list);
2359
2360 list_for_each_entry_rcu(srp, &skp->smk_rules, list)
2361 smk_rule_show(s, srp, SMK_LONGLABEL);
2362
2363 return 0;
2364 }
2365
2366 static const struct seq_operations load2_seq_ops = {
2367 .start = load2_seq_start,
2368 .next = load2_seq_next,
2369 .show = load2_seq_show,
2370 .stop = smk_seq_stop,
2371 };
2372
2373 /**
2374 * smk_open_load2 - open() for /smack/load2
2375 * @inode: inode structure representing file
2376 * @file: "load2" file pointer
2377 *
2378 * For reading, use load2_seq_* seq_file reading operations.
2379 */
smk_open_load2(struct inode * inode,struct file * file)2380 static int smk_open_load2(struct inode *inode, struct file *file)
2381 {
2382 return seq_open(file, &load2_seq_ops);
2383 }
2384
2385 /**
2386 * smk_write_load2 - write() for /smack/load2
2387 * @file: file pointer, not actually used
2388 * @buf: where to get the data from
2389 * @count: bytes sent
2390 * @ppos: where to start - must be 0
2391 *
2392 */
smk_write_load2(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2393 static ssize_t smk_write_load2(struct file *file, const char __user *buf,
2394 size_t count, loff_t *ppos)
2395 {
2396 /*
2397 * Must have privilege.
2398 */
2399 if (!smack_privileged(CAP_MAC_ADMIN))
2400 return -EPERM;
2401
2402 return smk_write_rules_list(file, buf, count, ppos, NULL, NULL,
2403 SMK_LONG_FMT);
2404 }
2405
2406 static const struct file_operations smk_load2_ops = {
2407 .open = smk_open_load2,
2408 .read = seq_read,
2409 .llseek = seq_lseek,
2410 .write = smk_write_load2,
2411 .release = seq_release,
2412 };
2413
2414 /*
2415 * Seq_file read operations for /smack/load-self2
2416 */
2417
load_self2_seq_start(struct seq_file * s,loff_t * pos)2418 static void *load_self2_seq_start(struct seq_file *s, loff_t *pos)
2419 {
2420 struct task_smack *tsp = smack_cred(current_cred());
2421
2422 return smk_seq_start(s, pos, &tsp->smk_rules);
2423 }
2424
load_self2_seq_next(struct seq_file * s,void * v,loff_t * pos)2425 static void *load_self2_seq_next(struct seq_file *s, void *v, loff_t *pos)
2426 {
2427 struct task_smack *tsp = smack_cred(current_cred());
2428
2429 return smk_seq_next(s, v, pos, &tsp->smk_rules);
2430 }
2431
load_self2_seq_show(struct seq_file * s,void * v)2432 static int load_self2_seq_show(struct seq_file *s, void *v)
2433 {
2434 struct list_head *list = v;
2435 struct smack_rule *srp =
2436 list_entry_rcu(list, struct smack_rule, list);
2437
2438 smk_rule_show(s, srp, SMK_LONGLABEL);
2439
2440 return 0;
2441 }
2442
2443 static const struct seq_operations load_self2_seq_ops = {
2444 .start = load_self2_seq_start,
2445 .next = load_self2_seq_next,
2446 .show = load_self2_seq_show,
2447 .stop = smk_seq_stop,
2448 };
2449
2450 /**
2451 * smk_open_load_self2 - open() for /smack/load-self2
2452 * @inode: inode structure representing file
2453 * @file: "load" file pointer
2454 *
2455 * For reading, use load_seq_* seq_file reading operations.
2456 */
smk_open_load_self2(struct inode * inode,struct file * file)2457 static int smk_open_load_self2(struct inode *inode, struct file *file)
2458 {
2459 return seq_open(file, &load_self2_seq_ops);
2460 }
2461
2462 /**
2463 * smk_write_load_self2 - write() for /smack/load-self2
2464 * @file: file pointer, not actually used
2465 * @buf: where to get the data from
2466 * @count: bytes sent
2467 * @ppos: where to start - must be 0
2468 *
2469 */
smk_write_load_self2(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2470 static ssize_t smk_write_load_self2(struct file *file, const char __user *buf,
2471 size_t count, loff_t *ppos)
2472 {
2473 struct task_smack *tsp = smack_cred(current_cred());
2474
2475 return smk_write_rules_list(file, buf, count, ppos, &tsp->smk_rules,
2476 &tsp->smk_rules_lock, SMK_LONG_FMT);
2477 }
2478
2479 static const struct file_operations smk_load_self2_ops = {
2480 .open = smk_open_load_self2,
2481 .read = seq_read,
2482 .llseek = seq_lseek,
2483 .write = smk_write_load_self2,
2484 .release = seq_release,
2485 };
2486
2487 /**
2488 * smk_write_access2 - handle access check transaction
2489 * @file: file pointer
2490 * @buf: data from user space
2491 * @count: bytes sent
2492 * @ppos: where to start - must be 0
2493 */
smk_write_access2(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2494 static ssize_t smk_write_access2(struct file *file, const char __user *buf,
2495 size_t count, loff_t *ppos)
2496 {
2497 return smk_user_access(file, buf, count, ppos, SMK_LONG_FMT);
2498 }
2499
2500 static const struct file_operations smk_access2_ops = {
2501 .write = smk_write_access2,
2502 .read = simple_transaction_read,
2503 .release = simple_transaction_release,
2504 .llseek = generic_file_llseek,
2505 };
2506
2507 /**
2508 * smk_write_revoke_subj - write() for /smack/revoke-subject
2509 * @file: file pointer
2510 * @buf: data from user space
2511 * @count: bytes sent
2512 * @ppos: where to start - must be 0
2513 */
smk_write_revoke_subj(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2514 static ssize_t smk_write_revoke_subj(struct file *file, const char __user *buf,
2515 size_t count, loff_t *ppos)
2516 {
2517 char *data;
2518 const char *cp;
2519 struct smack_known *skp;
2520 struct smack_rule *sp;
2521 struct list_head *rule_list;
2522 struct mutex *rule_lock;
2523 int rc = count;
2524
2525 if (*ppos != 0)
2526 return -EINVAL;
2527
2528 if (!smack_privileged(CAP_MAC_ADMIN))
2529 return -EPERM;
2530
2531 if (count == 0 || count > SMK_LONGLABEL)
2532 return -EINVAL;
2533
2534 data = memdup_user(buf, count);
2535 if (IS_ERR(data))
2536 return PTR_ERR(data);
2537
2538 cp = smk_parse_smack(data, count);
2539 if (IS_ERR(cp)) {
2540 rc = PTR_ERR(cp);
2541 goto out_data;
2542 }
2543
2544 skp = smk_find_entry(cp);
2545 if (skp == NULL)
2546 goto out_cp;
2547
2548 rule_list = &skp->smk_rules;
2549 rule_lock = &skp->smk_rules_lock;
2550
2551 mutex_lock(rule_lock);
2552
2553 list_for_each_entry_rcu(sp, rule_list, list)
2554 sp->smk_access = 0;
2555
2556 mutex_unlock(rule_lock);
2557
2558 out_cp:
2559 kfree(cp);
2560 out_data:
2561 kfree(data);
2562
2563 return rc;
2564 }
2565
2566 static const struct file_operations smk_revoke_subj_ops = {
2567 .write = smk_write_revoke_subj,
2568 .read = simple_transaction_read,
2569 .release = simple_transaction_release,
2570 .llseek = generic_file_llseek,
2571 };
2572
2573 /**
2574 * smk_init_sysfs - initialize /sys/fs/smackfs
2575 *
2576 */
smk_init_sysfs(void)2577 static int smk_init_sysfs(void)
2578 {
2579 return sysfs_create_mount_point(fs_kobj, "smackfs");
2580 }
2581
2582 /**
2583 * smk_write_change_rule - write() for /smack/change-rule
2584 * @file: file pointer
2585 * @buf: data from user space
2586 * @count: bytes sent
2587 * @ppos: where to start - must be 0
2588 */
smk_write_change_rule(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2589 static ssize_t smk_write_change_rule(struct file *file, const char __user *buf,
2590 size_t count, loff_t *ppos)
2591 {
2592 /*
2593 * Must have privilege.
2594 */
2595 if (!smack_privileged(CAP_MAC_ADMIN))
2596 return -EPERM;
2597
2598 return smk_write_rules_list(file, buf, count, ppos, NULL, NULL,
2599 SMK_CHANGE_FMT);
2600 }
2601
2602 static const struct file_operations smk_change_rule_ops = {
2603 .write = smk_write_change_rule,
2604 .read = simple_transaction_read,
2605 .release = simple_transaction_release,
2606 .llseek = generic_file_llseek,
2607 };
2608
2609 /**
2610 * smk_read_syslog - read() for smackfs/syslog
2611 * @filp: file pointer, not actually used
2612 * @buf: where to put the result
2613 * @cn: maximum to send along
2614 * @ppos: where to start
2615 *
2616 * Returns number of bytes read or error code, as appropriate
2617 */
smk_read_syslog(struct file * filp,char __user * buf,size_t cn,loff_t * ppos)2618 static ssize_t smk_read_syslog(struct file *filp, char __user *buf,
2619 size_t cn, loff_t *ppos)
2620 {
2621 struct smack_known *skp;
2622 ssize_t rc = -EINVAL;
2623 int asize;
2624
2625 if (*ppos != 0)
2626 return 0;
2627
2628 if (smack_syslog_label == NULL)
2629 skp = &smack_known_star;
2630 else
2631 skp = smack_syslog_label;
2632
2633 asize = strlen(skp->smk_known) + 1;
2634
2635 if (cn >= asize)
2636 rc = simple_read_from_buffer(buf, cn, ppos, skp->smk_known,
2637 asize);
2638
2639 return rc;
2640 }
2641
2642 /**
2643 * smk_write_syslog - write() for smackfs/syslog
2644 * @file: file pointer, not actually used
2645 * @buf: where to get the data from
2646 * @count: bytes sent
2647 * @ppos: where to start
2648 *
2649 * Returns number of bytes written or error code, as appropriate
2650 */
smk_write_syslog(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2651 static ssize_t smk_write_syslog(struct file *file, const char __user *buf,
2652 size_t count, loff_t *ppos)
2653 {
2654 char *data;
2655 struct smack_known *skp;
2656 int rc = count;
2657
2658 if (!smack_privileged(CAP_MAC_ADMIN))
2659 return -EPERM;
2660
2661 /* Enough data must be present */
2662 if (count == 0 || count > PAGE_SIZE)
2663 return -EINVAL;
2664
2665 data = memdup_user_nul(buf, count);
2666 if (IS_ERR(data))
2667 return PTR_ERR(data);
2668
2669 skp = smk_import_entry(data, count);
2670 if (IS_ERR(skp))
2671 rc = PTR_ERR(skp);
2672 else
2673 smack_syslog_label = skp;
2674
2675 kfree(data);
2676 return rc;
2677 }
2678
2679 static const struct file_operations smk_syslog_ops = {
2680 .read = smk_read_syslog,
2681 .write = smk_write_syslog,
2682 .llseek = default_llseek,
2683 };
2684
2685 /*
2686 * Seq_file read operations for /smack/relabel-self
2687 */
2688
relabel_self_seq_start(struct seq_file * s,loff_t * pos)2689 static void *relabel_self_seq_start(struct seq_file *s, loff_t *pos)
2690 {
2691 struct task_smack *tsp = smack_cred(current_cred());
2692
2693 return smk_seq_start(s, pos, &tsp->smk_relabel);
2694 }
2695
relabel_self_seq_next(struct seq_file * s,void * v,loff_t * pos)2696 static void *relabel_self_seq_next(struct seq_file *s, void *v, loff_t *pos)
2697 {
2698 struct task_smack *tsp = smack_cred(current_cred());
2699
2700 return smk_seq_next(s, v, pos, &tsp->smk_relabel);
2701 }
2702
relabel_self_seq_show(struct seq_file * s,void * v)2703 static int relabel_self_seq_show(struct seq_file *s, void *v)
2704 {
2705 struct list_head *list = v;
2706 struct smack_known_list_elem *sklep =
2707 list_entry(list, struct smack_known_list_elem, list);
2708
2709 seq_puts(s, sklep->smk_label->smk_known);
2710 seq_putc(s, ' ');
2711
2712 return 0;
2713 }
2714
2715 static const struct seq_operations relabel_self_seq_ops = {
2716 .start = relabel_self_seq_start,
2717 .next = relabel_self_seq_next,
2718 .show = relabel_self_seq_show,
2719 .stop = smk_seq_stop,
2720 };
2721
2722 /**
2723 * smk_open_relabel_self - open() for /smack/relabel-self
2724 * @inode: inode structure representing file
2725 * @file: "relabel-self" file pointer
2726 *
2727 * Connect our relabel_self_seq_* operations with /smack/relabel-self
2728 * file_operations
2729 */
smk_open_relabel_self(struct inode * inode,struct file * file)2730 static int smk_open_relabel_self(struct inode *inode, struct file *file)
2731 {
2732 return seq_open(file, &relabel_self_seq_ops);
2733 }
2734
2735 /**
2736 * smk_write_relabel_self - write() for /smack/relabel-self
2737 * @file: file pointer, not actually used
2738 * @buf: where to get the data from
2739 * @count: bytes sent
2740 * @ppos: where to start - must be 0
2741 *
2742 */
smk_write_relabel_self(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2743 static ssize_t smk_write_relabel_self(struct file *file, const char __user *buf,
2744 size_t count, loff_t *ppos)
2745 {
2746 char *data;
2747 int rc;
2748 LIST_HEAD(list_tmp);
2749
2750 /*
2751 * Must have privilege.
2752 */
2753 if (!smack_privileged(CAP_MAC_ADMIN))
2754 return -EPERM;
2755
2756 /*
2757 * No partial write.
2758 * Enough data must be present.
2759 */
2760 if (*ppos != 0)
2761 return -EINVAL;
2762 if (count == 0 || count > PAGE_SIZE)
2763 return -EINVAL;
2764
2765 data = memdup_user_nul(buf, count);
2766 if (IS_ERR(data))
2767 return PTR_ERR(data);
2768
2769 rc = smk_parse_label_list(data, &list_tmp);
2770 kfree(data);
2771
2772 if (!rc || (rc == -EINVAL && list_empty(&list_tmp))) {
2773 struct cred *new;
2774 struct task_smack *tsp;
2775
2776 new = prepare_creds();
2777 if (!new) {
2778 rc = -ENOMEM;
2779 goto out;
2780 }
2781 tsp = smack_cred(new);
2782 smk_destroy_label_list(&tsp->smk_relabel);
2783 list_splice(&list_tmp, &tsp->smk_relabel);
2784 commit_creds(new);
2785 return count;
2786 }
2787 out:
2788 smk_destroy_label_list(&list_tmp);
2789 return rc;
2790 }
2791
2792 static const struct file_operations smk_relabel_self_ops = {
2793 .open = smk_open_relabel_self,
2794 .read = seq_read,
2795 .llseek = seq_lseek,
2796 .write = smk_write_relabel_self,
2797 .release = seq_release,
2798 };
2799
2800 /**
2801 * smk_read_ptrace - read() for /smack/ptrace
2802 * @filp: file pointer, not actually used
2803 * @buf: where to put the result
2804 * @count: maximum to send along
2805 * @ppos: where to start
2806 *
2807 * Returns number of bytes read or error code, as appropriate
2808 */
smk_read_ptrace(struct file * filp,char __user * buf,size_t count,loff_t * ppos)2809 static ssize_t smk_read_ptrace(struct file *filp, char __user *buf,
2810 size_t count, loff_t *ppos)
2811 {
2812 char temp[32];
2813 ssize_t rc;
2814
2815 if (*ppos != 0)
2816 return 0;
2817
2818 sprintf(temp, "%d\n", smack_ptrace_rule);
2819 rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
2820 return rc;
2821 }
2822
2823 /**
2824 * smk_write_ptrace - write() for /smack/ptrace
2825 * @file: file pointer
2826 * @buf: data from user space
2827 * @count: bytes sent
2828 * @ppos: where to start - must be 0
2829 */
smk_write_ptrace(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2830 static ssize_t smk_write_ptrace(struct file *file, const char __user *buf,
2831 size_t count, loff_t *ppos)
2832 {
2833 char temp[32];
2834 int i;
2835
2836 if (!smack_privileged(CAP_MAC_ADMIN))
2837 return -EPERM;
2838
2839 if (*ppos != 0 || count >= sizeof(temp) || count == 0)
2840 return -EINVAL;
2841
2842 if (copy_from_user(temp, buf, count) != 0)
2843 return -EFAULT;
2844
2845 temp[count] = '\0';
2846
2847 if (sscanf(temp, "%d", &i) != 1)
2848 return -EINVAL;
2849 if (i < SMACK_PTRACE_DEFAULT || i > SMACK_PTRACE_MAX)
2850 return -EINVAL;
2851 smack_ptrace_rule = i;
2852
2853 return count;
2854 }
2855
2856 static const struct file_operations smk_ptrace_ops = {
2857 .write = smk_write_ptrace,
2858 .read = smk_read_ptrace,
2859 .llseek = default_llseek,
2860 };
2861
2862 /**
2863 * smk_fill_super - fill the smackfs superblock
2864 * @sb: the empty superblock
2865 * @fc: unused
2866 *
2867 * Fill in the well known entries for the smack filesystem
2868 *
2869 * Returns 0 on success, an error code on failure
2870 */
smk_fill_super(struct super_block * sb,struct fs_context * fc)2871 static int smk_fill_super(struct super_block *sb, struct fs_context *fc)
2872 {
2873 int rc;
2874
2875 static const struct tree_descr smack_files[] = {
2876 [SMK_LOAD] = {
2877 "load", &smk_load_ops, S_IRUGO|S_IWUSR},
2878 [SMK_CIPSO] = {
2879 "cipso", &smk_cipso_ops, S_IRUGO|S_IWUSR},
2880 [SMK_DOI] = {
2881 "doi", &smk_doi_ops, S_IRUGO|S_IWUSR},
2882 [SMK_DIRECT] = {
2883 "direct", &smk_direct_ops, S_IRUGO|S_IWUSR},
2884 [SMK_AMBIENT] = {
2885 "ambient", &smk_ambient_ops, S_IRUGO|S_IWUSR},
2886 [SMK_NET4ADDR] = {
2887 "netlabel", &smk_net4addr_ops, S_IRUGO|S_IWUSR},
2888 [SMK_ONLYCAP] = {
2889 "onlycap", &smk_onlycap_ops, S_IRUGO|S_IWUSR},
2890 [SMK_LOGGING] = {
2891 "logging", &smk_logging_ops, S_IRUGO|S_IWUSR},
2892 [SMK_LOAD_SELF] = {
2893 "load-self", &smk_load_self_ops, S_IRUGO|S_IWUGO},
2894 [SMK_ACCESSES] = {
2895 "access", &smk_access_ops, S_IRUGO|S_IWUGO},
2896 [SMK_MAPPED] = {
2897 "mapped", &smk_mapped_ops, S_IRUGO|S_IWUSR},
2898 [SMK_LOAD2] = {
2899 "load2", &smk_load2_ops, S_IRUGO|S_IWUSR},
2900 [SMK_LOAD_SELF2] = {
2901 "load-self2", &smk_load_self2_ops, S_IRUGO|S_IWUGO},
2902 [SMK_ACCESS2] = {
2903 "access2", &smk_access2_ops, S_IRUGO|S_IWUGO},
2904 [SMK_CIPSO2] = {
2905 "cipso2", &smk_cipso2_ops, S_IRUGO|S_IWUSR},
2906 [SMK_REVOKE_SUBJ] = {
2907 "revoke-subject", &smk_revoke_subj_ops,
2908 S_IRUGO|S_IWUSR},
2909 [SMK_CHANGE_RULE] = {
2910 "change-rule", &smk_change_rule_ops, S_IRUGO|S_IWUSR},
2911 [SMK_SYSLOG] = {
2912 "syslog", &smk_syslog_ops, S_IRUGO|S_IWUSR},
2913 [SMK_PTRACE] = {
2914 "ptrace", &smk_ptrace_ops, S_IRUGO|S_IWUSR},
2915 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
2916 [SMK_UNCONFINED] = {
2917 "unconfined", &smk_unconfined_ops, S_IRUGO|S_IWUSR},
2918 #endif
2919 #if IS_ENABLED(CONFIG_IPV6)
2920 [SMK_NET6ADDR] = {
2921 "ipv6host", &smk_net6addr_ops, S_IRUGO|S_IWUSR},
2922 #endif /* CONFIG_IPV6 */
2923 [SMK_RELABEL_SELF] = {
2924 "relabel-self", &smk_relabel_self_ops,
2925 S_IRUGO|S_IWUGO},
2926 /* last one */
2927 {""}
2928 };
2929
2930 rc = simple_fill_super(sb, SMACK_MAGIC, smack_files);
2931 if (rc != 0) {
2932 printk(KERN_ERR "%s failed %d while creating inodes\n",
2933 __func__, rc);
2934 return rc;
2935 }
2936
2937 return 0;
2938 }
2939
2940 /**
2941 * smk_get_tree - get the smackfs superblock
2942 * @fc: The mount context, including any options
2943 *
2944 * Just passes everything along.
2945 *
2946 * Returns what the lower level code does.
2947 */
smk_get_tree(struct fs_context * fc)2948 static int smk_get_tree(struct fs_context *fc)
2949 {
2950 return get_tree_single(fc, smk_fill_super);
2951 }
2952
2953 static const struct fs_context_operations smk_context_ops = {
2954 .get_tree = smk_get_tree,
2955 };
2956
2957 /**
2958 * smk_init_fs_context - Initialise a filesystem context for smackfs
2959 * @fc: The blank mount context
2960 */
smk_init_fs_context(struct fs_context * fc)2961 static int smk_init_fs_context(struct fs_context *fc)
2962 {
2963 fc->ops = &smk_context_ops;
2964 return 0;
2965 }
2966
2967 static struct file_system_type smk_fs_type = {
2968 .name = "smackfs",
2969 .init_fs_context = smk_init_fs_context,
2970 .kill_sb = kill_litter_super,
2971 };
2972
2973 static struct vfsmount *smackfs_mount;
2974
2975 /**
2976 * init_smk_fs - get the smackfs superblock
2977 *
2978 * register the smackfs
2979 *
2980 * Do not register smackfs if Smack wasn't enabled
2981 * on boot. We can not put this method normally under the
2982 * smack_init() code path since the security subsystem get
2983 * initialized before the vfs caches.
2984 *
2985 * Returns true if we were not chosen on boot or if
2986 * we were chosen and filesystem registration succeeded.
2987 */
init_smk_fs(void)2988 static int __init init_smk_fs(void)
2989 {
2990 int err;
2991 int rc;
2992
2993 if (smack_enabled == 0)
2994 return 0;
2995
2996 err = smk_init_sysfs();
2997 if (err)
2998 printk(KERN_ERR "smackfs: sysfs mountpoint problem.\n");
2999
3000 err = register_filesystem(&smk_fs_type);
3001 if (!err) {
3002 smackfs_mount = kern_mount(&smk_fs_type);
3003 if (IS_ERR(smackfs_mount)) {
3004 printk(KERN_ERR "smackfs: could not mount!\n");
3005 err = PTR_ERR(smackfs_mount);
3006 smackfs_mount = NULL;
3007 }
3008 }
3009
3010 smk_cipso_doi();
3011 smk_unlbl_ambient(NULL);
3012
3013 rc = smack_populate_secattr(&smack_known_floor);
3014 if (err == 0 && rc < 0)
3015 err = rc;
3016 rc = smack_populate_secattr(&smack_known_hat);
3017 if (err == 0 && rc < 0)
3018 err = rc;
3019 rc = smack_populate_secattr(&smack_known_huh);
3020 if (err == 0 && rc < 0)
3021 err = rc;
3022 rc = smack_populate_secattr(&smack_known_star);
3023 if (err == 0 && rc < 0)
3024 err = rc;
3025 rc = smack_populate_secattr(&smack_known_web);
3026 if (err == 0 && rc < 0)
3027 err = rc;
3028
3029 return err;
3030 }
3031
3032 __initcall(init_smk_fs);
3033