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 | __GFP_NOFAIL);
697 doip->map.std = NULL;
698 doip->doi = smk_cipso_doi_value;
699 doip->type = CIPSO_V4_MAP_PASS;
700 doip->tags[0] = CIPSO_V4_TAG_RBITMAP;
701 for (rc = 1; rc < CIPSO_V4_TAG_MAXCNT; rc++)
702 doip->tags[rc] = CIPSO_V4_TAG_INVALID;
703
704 rc = netlbl_cfg_cipsov4_add(doip, &nai);
705 if (rc != 0) {
706 printk(KERN_WARNING "%s:%d cipso add rc = %d\n",
707 __func__, __LINE__, rc);
708 kfree(doip);
709 return;
710 }
711 rc = netlbl_cfg_cipsov4_map_add(doip->doi, NULL, NULL, NULL, &nai);
712 if (rc != 0) {
713 printk(KERN_WARNING "%s:%d map add rc = %d\n",
714 __func__, __LINE__, rc);
715 netlbl_cfg_cipsov4_del(doip->doi, &nai);
716 return;
717 }
718 }
719
720 /**
721 * smk_unlbl_ambient - initialize the unlabeled domain
722 * @oldambient: previous domain string
723 */
smk_unlbl_ambient(char * oldambient)724 static void smk_unlbl_ambient(char *oldambient)
725 {
726 int rc;
727 struct netlbl_audit nai;
728
729 smk_netlabel_audit_set(&nai);
730
731 if (oldambient != NULL) {
732 rc = netlbl_cfg_map_del(oldambient, PF_INET, NULL, NULL, &nai);
733 if (rc != 0)
734 printk(KERN_WARNING "%s:%d remove rc = %d\n",
735 __func__, __LINE__, rc);
736 }
737 if (smack_net_ambient == NULL)
738 smack_net_ambient = &smack_known_floor;
739
740 rc = netlbl_cfg_unlbl_map_add(smack_net_ambient->smk_known, PF_INET,
741 NULL, NULL, &nai);
742 if (rc != 0)
743 printk(KERN_WARNING "%s:%d add rc = %d\n",
744 __func__, __LINE__, rc);
745 }
746
747 /*
748 * Seq_file read operations for /smack/cipso
749 */
750
cipso_seq_start(struct seq_file * s,loff_t * pos)751 static void *cipso_seq_start(struct seq_file *s, loff_t *pos)
752 {
753 return smk_seq_start(s, pos, &smack_known_list);
754 }
755
cipso_seq_next(struct seq_file * s,void * v,loff_t * pos)756 static void *cipso_seq_next(struct seq_file *s, void *v, loff_t *pos)
757 {
758 return smk_seq_next(s, v, pos, &smack_known_list);
759 }
760
761 /*
762 * Print cipso labels in format:
763 * label level[/cat[,cat]]
764 */
cipso_seq_show(struct seq_file * s,void * v)765 static int cipso_seq_show(struct seq_file *s, void *v)
766 {
767 struct list_head *list = v;
768 struct smack_known *skp =
769 list_entry_rcu(list, struct smack_known, list);
770 struct netlbl_lsm_catmap *cmp = skp->smk_netlabel.attr.mls.cat;
771 char sep = '/';
772 int i;
773
774 /*
775 * Don't show a label that could not have been set using
776 * /smack/cipso. This is in support of the notion that
777 * anything read from /smack/cipso ought to be writeable
778 * to /smack/cipso.
779 *
780 * /smack/cipso2 should be used instead.
781 */
782 if (strlen(skp->smk_known) >= SMK_LABELLEN)
783 return 0;
784
785 seq_printf(s, "%s %3d", skp->smk_known, skp->smk_netlabel.attr.mls.lvl);
786
787 for (i = netlbl_catmap_walk(cmp, 0); i >= 0;
788 i = netlbl_catmap_walk(cmp, i + 1)) {
789 seq_printf(s, "%c%d", sep, i);
790 sep = ',';
791 }
792
793 seq_putc(s, '\n');
794
795 return 0;
796 }
797
798 static const struct seq_operations cipso_seq_ops = {
799 .start = cipso_seq_start,
800 .next = cipso_seq_next,
801 .show = cipso_seq_show,
802 .stop = smk_seq_stop,
803 };
804
805 /**
806 * smk_open_cipso - open() for /smack/cipso
807 * @inode: inode structure representing file
808 * @file: "cipso" file pointer
809 *
810 * Connect our cipso_seq_* operations with /smack/cipso
811 * file_operations
812 */
smk_open_cipso(struct inode * inode,struct file * file)813 static int smk_open_cipso(struct inode *inode, struct file *file)
814 {
815 return seq_open(file, &cipso_seq_ops);
816 }
817
818 /**
819 * smk_set_cipso - do the work for write() for cipso and cipso2
820 * @file: file pointer, not actually used
821 * @buf: where to get the data from
822 * @count: bytes sent
823 * @ppos: where to start
824 * @format: /smack/cipso or /smack/cipso2
825 *
826 * Accepts only one cipso rule per write call.
827 * Returns number of bytes written or error code, as appropriate
828 */
smk_set_cipso(struct file * file,const char __user * buf,size_t count,loff_t * ppos,int format)829 static ssize_t smk_set_cipso(struct file *file, const char __user *buf,
830 size_t count, loff_t *ppos, int format)
831 {
832 struct netlbl_lsm_catmap *old_cat;
833 struct smack_known *skp;
834 struct netlbl_lsm_secattr ncats;
835 char mapcatset[SMK_CIPSOLEN];
836 int maplevel;
837 unsigned int cat;
838 int catlen;
839 ssize_t rc = -EINVAL;
840 char *data = NULL;
841 char *rule;
842 int ret;
843 int i;
844
845 /*
846 * Must have privilege.
847 * No partial writes.
848 * Enough data must be present.
849 */
850 if (!smack_privileged(CAP_MAC_ADMIN))
851 return -EPERM;
852 if (*ppos != 0)
853 return -EINVAL;
854 if (format == SMK_FIXED24_FMT &&
855 (count < SMK_CIPSOMIN || count > SMK_CIPSOMAX))
856 return -EINVAL;
857 if (count > PAGE_SIZE)
858 return -EINVAL;
859
860 data = memdup_user_nul(buf, count);
861 if (IS_ERR(data))
862 return PTR_ERR(data);
863
864 rule = data;
865 /*
866 * Only allow one writer at a time. Writes should be
867 * quite rare and small in any case.
868 */
869 mutex_lock(&smack_cipso_lock);
870
871 skp = smk_import_entry(rule, 0);
872 if (IS_ERR(skp)) {
873 rc = PTR_ERR(skp);
874 goto out;
875 }
876
877 if (format == SMK_FIXED24_FMT)
878 rule += SMK_LABELLEN;
879 else
880 rule += strlen(skp->smk_known) + 1;
881
882 if (rule > data + count) {
883 rc = -EOVERFLOW;
884 goto out;
885 }
886
887 ret = sscanf(rule, "%d", &maplevel);
888 if (ret != 1 || maplevel < 0 || maplevel > SMACK_CIPSO_MAXLEVEL)
889 goto out;
890
891 rule += SMK_DIGITLEN;
892 if (rule > data + count) {
893 rc = -EOVERFLOW;
894 goto out;
895 }
896
897 ret = sscanf(rule, "%d", &catlen);
898 if (ret != 1 || catlen > SMACK_CIPSO_MAXCATNUM)
899 goto out;
900
901 if (format == SMK_FIXED24_FMT &&
902 count != (SMK_CIPSOMIN + catlen * SMK_DIGITLEN))
903 goto out;
904
905 memset(mapcatset, 0, sizeof(mapcatset));
906
907 for (i = 0; i < catlen; i++) {
908 rule += SMK_DIGITLEN;
909 if (rule > data + count) {
910 rc = -EOVERFLOW;
911 goto out;
912 }
913 ret = sscanf(rule, "%u", &cat);
914 if (ret != 1 || cat > SMACK_CIPSO_MAXCATNUM)
915 goto out;
916
917 smack_catset_bit(cat, mapcatset);
918 }
919
920 rc = smk_netlbl_mls(maplevel, mapcatset, &ncats, SMK_CIPSOLEN);
921 if (rc >= 0) {
922 old_cat = skp->smk_netlabel.attr.mls.cat;
923 skp->smk_netlabel.attr.mls.cat = ncats.attr.mls.cat;
924 skp->smk_netlabel.attr.mls.lvl = ncats.attr.mls.lvl;
925 synchronize_rcu();
926 netlbl_catmap_free(old_cat);
927 rc = count;
928 /*
929 * This mapping may have been cached, so clear the cache.
930 */
931 netlbl_cache_invalidate();
932 }
933
934 out:
935 mutex_unlock(&smack_cipso_lock);
936 kfree(data);
937 return rc;
938 }
939
940 /**
941 * smk_write_cipso - write() for /smack/cipso
942 * @file: file pointer, not actually used
943 * @buf: where to get the data from
944 * @count: bytes sent
945 * @ppos: where to start
946 *
947 * Accepts only one cipso rule per write call.
948 * Returns number of bytes written or error code, as appropriate
949 */
smk_write_cipso(struct file * file,const char __user * buf,size_t count,loff_t * ppos)950 static ssize_t smk_write_cipso(struct file *file, const char __user *buf,
951 size_t count, loff_t *ppos)
952 {
953 return smk_set_cipso(file, buf, count, ppos, SMK_FIXED24_FMT);
954 }
955
956 static const struct file_operations smk_cipso_ops = {
957 .open = smk_open_cipso,
958 .read = seq_read,
959 .llseek = seq_lseek,
960 .write = smk_write_cipso,
961 .release = seq_release,
962 };
963
964 /*
965 * Seq_file read operations for /smack/cipso2
966 */
967
968 /*
969 * Print cipso labels in format:
970 * label level[/cat[,cat]]
971 */
cipso2_seq_show(struct seq_file * s,void * v)972 static int cipso2_seq_show(struct seq_file *s, void *v)
973 {
974 struct list_head *list = v;
975 struct smack_known *skp =
976 list_entry_rcu(list, struct smack_known, list);
977 struct netlbl_lsm_catmap *cmp = skp->smk_netlabel.attr.mls.cat;
978 char sep = '/';
979 int i;
980
981 seq_printf(s, "%s %3d", skp->smk_known, skp->smk_netlabel.attr.mls.lvl);
982
983 for (i = netlbl_catmap_walk(cmp, 0); i >= 0;
984 i = netlbl_catmap_walk(cmp, i + 1)) {
985 seq_printf(s, "%c%d", sep, i);
986 sep = ',';
987 }
988
989 seq_putc(s, '\n');
990
991 return 0;
992 }
993
994 static const struct seq_operations cipso2_seq_ops = {
995 .start = cipso_seq_start,
996 .next = cipso_seq_next,
997 .show = cipso2_seq_show,
998 .stop = smk_seq_stop,
999 };
1000
1001 /**
1002 * smk_open_cipso2 - open() for /smack/cipso2
1003 * @inode: inode structure representing file
1004 * @file: "cipso2" file pointer
1005 *
1006 * Connect our cipso_seq_* operations with /smack/cipso2
1007 * file_operations
1008 */
smk_open_cipso2(struct inode * inode,struct file * file)1009 static int smk_open_cipso2(struct inode *inode, struct file *file)
1010 {
1011 return seq_open(file, &cipso2_seq_ops);
1012 }
1013
1014 /**
1015 * smk_write_cipso2 - write() for /smack/cipso2
1016 * @file: file pointer, not actually used
1017 * @buf: where to get the data from
1018 * @count: bytes sent
1019 * @ppos: where to start
1020 *
1021 * Accepts only one cipso rule per write call.
1022 * Returns number of bytes written or error code, as appropriate
1023 */
smk_write_cipso2(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1024 static ssize_t smk_write_cipso2(struct file *file, const char __user *buf,
1025 size_t count, loff_t *ppos)
1026 {
1027 return smk_set_cipso(file, buf, count, ppos, SMK_LONG_FMT);
1028 }
1029
1030 static const struct file_operations smk_cipso2_ops = {
1031 .open = smk_open_cipso2,
1032 .read = seq_read,
1033 .llseek = seq_lseek,
1034 .write = smk_write_cipso2,
1035 .release = seq_release,
1036 };
1037
1038 /*
1039 * Seq_file read operations for /smack/netlabel
1040 */
1041
net4addr_seq_start(struct seq_file * s,loff_t * pos)1042 static void *net4addr_seq_start(struct seq_file *s, loff_t *pos)
1043 {
1044 return smk_seq_start(s, pos, &smk_net4addr_list);
1045 }
1046
net4addr_seq_next(struct seq_file * s,void * v,loff_t * pos)1047 static void *net4addr_seq_next(struct seq_file *s, void *v, loff_t *pos)
1048 {
1049 return smk_seq_next(s, v, pos, &smk_net4addr_list);
1050 }
1051
1052 /*
1053 * Print host/label pairs
1054 */
net4addr_seq_show(struct seq_file * s,void * v)1055 static int net4addr_seq_show(struct seq_file *s, void *v)
1056 {
1057 struct list_head *list = v;
1058 struct smk_net4addr *skp =
1059 list_entry_rcu(list, struct smk_net4addr, list);
1060 char *kp = SMACK_CIPSO_OPTION;
1061
1062 if (skp->smk_label != NULL)
1063 kp = skp->smk_label->smk_known;
1064 seq_printf(s, "%pI4/%d %s\n", &skp->smk_host.s_addr,
1065 skp->smk_masks, kp);
1066
1067 return 0;
1068 }
1069
1070 static const struct seq_operations net4addr_seq_ops = {
1071 .start = net4addr_seq_start,
1072 .next = net4addr_seq_next,
1073 .show = net4addr_seq_show,
1074 .stop = smk_seq_stop,
1075 };
1076
1077 /**
1078 * smk_open_net4addr - open() for /smack/netlabel
1079 * @inode: inode structure representing file
1080 * @file: "netlabel" file pointer
1081 *
1082 * Connect our net4addr_seq_* operations with /smack/netlabel
1083 * file_operations
1084 */
smk_open_net4addr(struct inode * inode,struct file * file)1085 static int smk_open_net4addr(struct inode *inode, struct file *file)
1086 {
1087 return seq_open(file, &net4addr_seq_ops);
1088 }
1089
1090 /**
1091 * smk_net4addr_insert
1092 * @new : netlabel to insert
1093 *
1094 * This helper insert netlabel in the smack_net4addrs list
1095 * sorted by netmask length (longest to smallest)
1096 * locked by &smk_net4addr_lock in smk_write_net4addr
1097 *
1098 */
smk_net4addr_insert(struct smk_net4addr * new)1099 static void smk_net4addr_insert(struct smk_net4addr *new)
1100 {
1101 struct smk_net4addr *m;
1102 struct smk_net4addr *m_next;
1103
1104 if (list_empty(&smk_net4addr_list)) {
1105 list_add_rcu(&new->list, &smk_net4addr_list);
1106 return;
1107 }
1108
1109 m = list_entry_rcu(smk_net4addr_list.next,
1110 struct smk_net4addr, list);
1111
1112 /* the comparison '>' is a bit hacky, but works */
1113 if (new->smk_masks > m->smk_masks) {
1114 list_add_rcu(&new->list, &smk_net4addr_list);
1115 return;
1116 }
1117
1118 list_for_each_entry_rcu(m, &smk_net4addr_list, list) {
1119 if (list_is_last(&m->list, &smk_net4addr_list)) {
1120 list_add_rcu(&new->list, &m->list);
1121 return;
1122 }
1123 m_next = list_entry_rcu(m->list.next,
1124 struct smk_net4addr, list);
1125 if (new->smk_masks > m_next->smk_masks) {
1126 list_add_rcu(&new->list, &m->list);
1127 return;
1128 }
1129 }
1130 }
1131
1132
1133 /**
1134 * smk_write_net4addr - write() for /smack/netlabel
1135 * @file: file pointer, not actually used
1136 * @buf: where to get the data from
1137 * @count: bytes sent
1138 * @ppos: where to start
1139 *
1140 * Accepts only one net4addr per write call.
1141 * Returns number of bytes written or error code, as appropriate
1142 */
smk_write_net4addr(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1143 static ssize_t smk_write_net4addr(struct file *file, const char __user *buf,
1144 size_t count, loff_t *ppos)
1145 {
1146 struct smk_net4addr *snp;
1147 struct sockaddr_in newname;
1148 char *smack;
1149 struct smack_known *skp = NULL;
1150 char *data;
1151 char *host = (char *)&newname.sin_addr.s_addr;
1152 int rc;
1153 struct netlbl_audit audit_info;
1154 struct in_addr mask;
1155 unsigned int m;
1156 unsigned int masks;
1157 int found;
1158 u32 mask_bits = (1<<31);
1159 __be32 nsa;
1160 u32 temp_mask;
1161
1162 /*
1163 * Must have privilege.
1164 * No partial writes.
1165 * Enough data must be present.
1166 * "<addr/mask, as a.b.c.d/e><space><label>"
1167 * "<addr, as a.b.c.d><space><label>"
1168 */
1169 if (!smack_privileged(CAP_MAC_ADMIN))
1170 return -EPERM;
1171 if (*ppos != 0)
1172 return -EINVAL;
1173 if (count < SMK_NETLBLADDRMIN || count > PAGE_SIZE - 1)
1174 return -EINVAL;
1175
1176 data = memdup_user_nul(buf, count);
1177 if (IS_ERR(data))
1178 return PTR_ERR(data);
1179
1180 smack = kzalloc(count + 1, GFP_KERNEL);
1181 if (smack == NULL) {
1182 rc = -ENOMEM;
1183 goto free_data_out;
1184 }
1185
1186 rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd/%u %s",
1187 &host[0], &host[1], &host[2], &host[3], &masks, smack);
1188 if (rc != 6) {
1189 rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd %s",
1190 &host[0], &host[1], &host[2], &host[3], smack);
1191 if (rc != 5) {
1192 rc = -EINVAL;
1193 goto free_out;
1194 }
1195 m = BEBITS;
1196 masks = 32;
1197 }
1198 if (masks > BEBITS) {
1199 rc = -EINVAL;
1200 goto free_out;
1201 }
1202
1203 /*
1204 * If smack begins with '-', it is an option, don't import it
1205 */
1206 if (smack[0] != '-') {
1207 skp = smk_import_entry(smack, 0);
1208 if (IS_ERR(skp)) {
1209 rc = PTR_ERR(skp);
1210 goto free_out;
1211 }
1212 } else {
1213 /*
1214 * Only the -CIPSO option is supported for IPv4
1215 */
1216 if (strcmp(smack, SMACK_CIPSO_OPTION) != 0) {
1217 rc = -EINVAL;
1218 goto free_out;
1219 }
1220 }
1221
1222 for (m = masks, temp_mask = 0; m > 0; m--) {
1223 temp_mask |= mask_bits;
1224 mask_bits >>= 1;
1225 }
1226 mask.s_addr = cpu_to_be32(temp_mask);
1227
1228 newname.sin_addr.s_addr &= mask.s_addr;
1229 /*
1230 * Only allow one writer at a time. Writes should be
1231 * quite rare and small in any case.
1232 */
1233 mutex_lock(&smk_net4addr_lock);
1234
1235 nsa = newname.sin_addr.s_addr;
1236 /* try to find if the prefix is already in the list */
1237 found = 0;
1238 list_for_each_entry_rcu(snp, &smk_net4addr_list, list) {
1239 if (snp->smk_host.s_addr == nsa && snp->smk_masks == masks) {
1240 found = 1;
1241 break;
1242 }
1243 }
1244 smk_netlabel_audit_set(&audit_info);
1245
1246 if (found == 0) {
1247 snp = kzalloc(sizeof(*snp), GFP_KERNEL);
1248 if (snp == NULL)
1249 rc = -ENOMEM;
1250 else {
1251 rc = 0;
1252 snp->smk_host.s_addr = newname.sin_addr.s_addr;
1253 snp->smk_mask.s_addr = mask.s_addr;
1254 snp->smk_label = skp;
1255 snp->smk_masks = masks;
1256 smk_net4addr_insert(snp);
1257 }
1258 } else {
1259 /*
1260 * Delete the unlabeled entry, only if the previous label
1261 * wasn't the special CIPSO option
1262 */
1263 if (snp->smk_label != NULL)
1264 rc = netlbl_cfg_unlbl_static_del(&init_net, NULL,
1265 &snp->smk_host, &snp->smk_mask,
1266 PF_INET, &audit_info);
1267 else
1268 rc = 0;
1269 snp->smk_label = skp;
1270 }
1271
1272 /*
1273 * Now tell netlabel about the single label nature of
1274 * this host so that incoming packets get labeled.
1275 * but only if we didn't get the special CIPSO option
1276 */
1277 if (rc == 0 && skp != NULL)
1278 rc = netlbl_cfg_unlbl_static_add(&init_net, NULL,
1279 &snp->smk_host, &snp->smk_mask, PF_INET,
1280 snp->smk_label->smk_secid, &audit_info);
1281
1282 if (rc == 0)
1283 rc = count;
1284
1285 mutex_unlock(&smk_net4addr_lock);
1286
1287 free_out:
1288 kfree(smack);
1289 free_data_out:
1290 kfree(data);
1291
1292 return rc;
1293 }
1294
1295 static const struct file_operations smk_net4addr_ops = {
1296 .open = smk_open_net4addr,
1297 .read = seq_read,
1298 .llseek = seq_lseek,
1299 .write = smk_write_net4addr,
1300 .release = seq_release,
1301 };
1302
1303 #if IS_ENABLED(CONFIG_IPV6)
1304 /*
1305 * Seq_file read operations for /smack/netlabel6
1306 */
1307
net6addr_seq_start(struct seq_file * s,loff_t * pos)1308 static void *net6addr_seq_start(struct seq_file *s, loff_t *pos)
1309 {
1310 return smk_seq_start(s, pos, &smk_net6addr_list);
1311 }
1312
net6addr_seq_next(struct seq_file * s,void * v,loff_t * pos)1313 static void *net6addr_seq_next(struct seq_file *s, void *v, loff_t *pos)
1314 {
1315 return smk_seq_next(s, v, pos, &smk_net6addr_list);
1316 }
1317
1318 /*
1319 * Print host/label pairs
1320 */
net6addr_seq_show(struct seq_file * s,void * v)1321 static int net6addr_seq_show(struct seq_file *s, void *v)
1322 {
1323 struct list_head *list = v;
1324 struct smk_net6addr *skp =
1325 list_entry(list, struct smk_net6addr, list);
1326
1327 if (skp->smk_label != NULL)
1328 seq_printf(s, "%pI6/%d %s\n", &skp->smk_host, skp->smk_masks,
1329 skp->smk_label->smk_known);
1330
1331 return 0;
1332 }
1333
1334 static const struct seq_operations net6addr_seq_ops = {
1335 .start = net6addr_seq_start,
1336 .next = net6addr_seq_next,
1337 .show = net6addr_seq_show,
1338 .stop = smk_seq_stop,
1339 };
1340
1341 /**
1342 * smk_open_net6addr - open() for /smack/netlabel
1343 * @inode: inode structure representing file
1344 * @file: "netlabel" file pointer
1345 *
1346 * Connect our net6addr_seq_* operations with /smack/netlabel
1347 * file_operations
1348 */
smk_open_net6addr(struct inode * inode,struct file * file)1349 static int smk_open_net6addr(struct inode *inode, struct file *file)
1350 {
1351 return seq_open(file, &net6addr_seq_ops);
1352 }
1353
1354 /**
1355 * smk_net6addr_insert
1356 * @new : entry to insert
1357 *
1358 * This inserts an entry in the smack_net6addrs list
1359 * sorted by netmask length (longest to smallest)
1360 * locked by &smk_net6addr_lock in smk_write_net6addr
1361 *
1362 */
smk_net6addr_insert(struct smk_net6addr * new)1363 static void smk_net6addr_insert(struct smk_net6addr *new)
1364 {
1365 struct smk_net6addr *m_next;
1366 struct smk_net6addr *m;
1367
1368 if (list_empty(&smk_net6addr_list)) {
1369 list_add_rcu(&new->list, &smk_net6addr_list);
1370 return;
1371 }
1372
1373 m = list_entry_rcu(smk_net6addr_list.next,
1374 struct smk_net6addr, list);
1375
1376 if (new->smk_masks > m->smk_masks) {
1377 list_add_rcu(&new->list, &smk_net6addr_list);
1378 return;
1379 }
1380
1381 list_for_each_entry_rcu(m, &smk_net6addr_list, list) {
1382 if (list_is_last(&m->list, &smk_net6addr_list)) {
1383 list_add_rcu(&new->list, &m->list);
1384 return;
1385 }
1386 m_next = list_entry_rcu(m->list.next,
1387 struct smk_net6addr, list);
1388 if (new->smk_masks > m_next->smk_masks) {
1389 list_add_rcu(&new->list, &m->list);
1390 return;
1391 }
1392 }
1393 }
1394
1395
1396 /**
1397 * smk_write_net6addr - write() for /smack/netlabel
1398 * @file: file pointer, not actually used
1399 * @buf: where to get the data from
1400 * @count: bytes sent
1401 * @ppos: where to start
1402 *
1403 * Accepts only one net6addr per write call.
1404 * Returns number of bytes written or error code, as appropriate
1405 */
smk_write_net6addr(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1406 static ssize_t smk_write_net6addr(struct file *file, const char __user *buf,
1407 size_t count, loff_t *ppos)
1408 {
1409 struct smk_net6addr *snp;
1410 struct in6_addr newname;
1411 struct in6_addr fullmask;
1412 struct smack_known *skp = NULL;
1413 char *smack;
1414 char *data;
1415 int rc = 0;
1416 int found = 0;
1417 int i;
1418 unsigned int scanned[8];
1419 unsigned int m;
1420 unsigned int mask = 128;
1421
1422 /*
1423 * Must have privilege.
1424 * No partial writes.
1425 * Enough data must be present.
1426 * "<addr/mask, as a:b:c:d:e:f:g:h/e><space><label>"
1427 * "<addr, as a:b:c:d:e:f:g:h><space><label>"
1428 */
1429 if (!smack_privileged(CAP_MAC_ADMIN))
1430 return -EPERM;
1431 if (*ppos != 0)
1432 return -EINVAL;
1433 if (count < SMK_NETLBLADDRMIN || count > PAGE_SIZE - 1)
1434 return -EINVAL;
1435
1436 data = memdup_user_nul(buf, count);
1437 if (IS_ERR(data))
1438 return PTR_ERR(data);
1439
1440 smack = kzalloc(count + 1, GFP_KERNEL);
1441 if (smack == NULL) {
1442 rc = -ENOMEM;
1443 goto free_data_out;
1444 }
1445
1446 i = sscanf(data, "%x:%x:%x:%x:%x:%x:%x:%x/%u %s",
1447 &scanned[0], &scanned[1], &scanned[2], &scanned[3],
1448 &scanned[4], &scanned[5], &scanned[6], &scanned[7],
1449 &mask, smack);
1450 if (i != 10) {
1451 i = sscanf(data, "%x:%x:%x:%x:%x:%x:%x:%x %s",
1452 &scanned[0], &scanned[1], &scanned[2],
1453 &scanned[3], &scanned[4], &scanned[5],
1454 &scanned[6], &scanned[7], smack);
1455 if (i != 9) {
1456 rc = -EINVAL;
1457 goto free_out;
1458 }
1459 }
1460 if (mask > 128) {
1461 rc = -EINVAL;
1462 goto free_out;
1463 }
1464 for (i = 0; i < 8; i++) {
1465 if (scanned[i] > 0xffff) {
1466 rc = -EINVAL;
1467 goto free_out;
1468 }
1469 newname.s6_addr16[i] = htons(scanned[i]);
1470 }
1471
1472 /*
1473 * If smack begins with '-', it is an option, don't import it
1474 */
1475 if (smack[0] != '-') {
1476 skp = smk_import_entry(smack, 0);
1477 if (IS_ERR(skp)) {
1478 rc = PTR_ERR(skp);
1479 goto free_out;
1480 }
1481 } else {
1482 /*
1483 * Only -DELETE is supported for IPv6
1484 */
1485 if (strcmp(smack, SMACK_DELETE_OPTION) != 0) {
1486 rc = -EINVAL;
1487 goto free_out;
1488 }
1489 }
1490
1491 for (i = 0, m = mask; i < 8; i++) {
1492 if (m >= 16) {
1493 fullmask.s6_addr16[i] = 0xffff;
1494 m -= 16;
1495 } else if (m > 0) {
1496 fullmask.s6_addr16[i] = (1 << m) - 1;
1497 m = 0;
1498 } else
1499 fullmask.s6_addr16[i] = 0;
1500 newname.s6_addr16[i] &= fullmask.s6_addr16[i];
1501 }
1502
1503 /*
1504 * Only allow one writer at a time. Writes should be
1505 * quite rare and small in any case.
1506 */
1507 mutex_lock(&smk_net6addr_lock);
1508 /*
1509 * Try to find the prefix in the list
1510 */
1511 list_for_each_entry_rcu(snp, &smk_net6addr_list, list) {
1512 if (mask != snp->smk_masks)
1513 continue;
1514 for (found = 1, i = 0; i < 8; i++) {
1515 if (newname.s6_addr16[i] !=
1516 snp->smk_host.s6_addr16[i]) {
1517 found = 0;
1518 break;
1519 }
1520 }
1521 if (found == 1)
1522 break;
1523 }
1524 if (found == 0) {
1525 snp = kzalloc(sizeof(*snp), GFP_KERNEL);
1526 if (snp == NULL)
1527 rc = -ENOMEM;
1528 else {
1529 snp->smk_host = newname;
1530 snp->smk_mask = fullmask;
1531 snp->smk_masks = mask;
1532 snp->smk_label = skp;
1533 smk_net6addr_insert(snp);
1534 }
1535 } else {
1536 snp->smk_label = skp;
1537 }
1538
1539 if (rc == 0)
1540 rc = count;
1541
1542 mutex_unlock(&smk_net6addr_lock);
1543
1544 free_out:
1545 kfree(smack);
1546 free_data_out:
1547 kfree(data);
1548
1549 return rc;
1550 }
1551
1552 static const struct file_operations smk_net6addr_ops = {
1553 .open = smk_open_net6addr,
1554 .read = seq_read,
1555 .llseek = seq_lseek,
1556 .write = smk_write_net6addr,
1557 .release = seq_release,
1558 };
1559 #endif /* CONFIG_IPV6 */
1560
1561 /**
1562 * smk_read_doi - read() for /smack/doi
1563 * @filp: file pointer, not actually used
1564 * @buf: where to put the result
1565 * @count: maximum to send along
1566 * @ppos: where to start
1567 *
1568 * Returns number of bytes read or error code, as appropriate
1569 */
smk_read_doi(struct file * filp,char __user * buf,size_t count,loff_t * ppos)1570 static ssize_t smk_read_doi(struct file *filp, char __user *buf,
1571 size_t count, loff_t *ppos)
1572 {
1573 char temp[80];
1574 ssize_t rc;
1575
1576 if (*ppos != 0)
1577 return 0;
1578
1579 sprintf(temp, "%d", smk_cipso_doi_value);
1580 rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
1581
1582 return rc;
1583 }
1584
1585 /**
1586 * smk_write_doi - write() for /smack/doi
1587 * @file: file pointer, not actually used
1588 * @buf: where to get the data from
1589 * @count: bytes sent
1590 * @ppos: where to start
1591 *
1592 * Returns number of bytes written or error code, as appropriate
1593 */
smk_write_doi(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1594 static ssize_t smk_write_doi(struct file *file, const char __user *buf,
1595 size_t count, loff_t *ppos)
1596 {
1597 char temp[80];
1598 int i;
1599
1600 if (!smack_privileged(CAP_MAC_ADMIN))
1601 return -EPERM;
1602
1603 if (count >= sizeof(temp) || count == 0)
1604 return -EINVAL;
1605
1606 if (copy_from_user(temp, buf, count) != 0)
1607 return -EFAULT;
1608
1609 temp[count] = '\0';
1610
1611 if (sscanf(temp, "%d", &i) != 1)
1612 return -EINVAL;
1613
1614 smk_cipso_doi_value = i;
1615
1616 smk_cipso_doi();
1617
1618 return count;
1619 }
1620
1621 static const struct file_operations smk_doi_ops = {
1622 .read = smk_read_doi,
1623 .write = smk_write_doi,
1624 .llseek = default_llseek,
1625 };
1626
1627 /**
1628 * smk_read_direct - read() for /smack/direct
1629 * @filp: file pointer, not actually used
1630 * @buf: where to put the result
1631 * @count: maximum to send along
1632 * @ppos: where to start
1633 *
1634 * Returns number of bytes read or error code, as appropriate
1635 */
smk_read_direct(struct file * filp,char __user * buf,size_t count,loff_t * ppos)1636 static ssize_t smk_read_direct(struct file *filp, char __user *buf,
1637 size_t count, loff_t *ppos)
1638 {
1639 char temp[80];
1640 ssize_t rc;
1641
1642 if (*ppos != 0)
1643 return 0;
1644
1645 sprintf(temp, "%d", smack_cipso_direct);
1646 rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
1647
1648 return rc;
1649 }
1650
1651 /**
1652 * smk_write_direct - write() for /smack/direct
1653 * @file: file pointer, not actually used
1654 * @buf: where to get the data from
1655 * @count: bytes sent
1656 * @ppos: where to start
1657 *
1658 * Returns number of bytes written or error code, as appropriate
1659 */
smk_write_direct(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1660 static ssize_t smk_write_direct(struct file *file, const char __user *buf,
1661 size_t count, loff_t *ppos)
1662 {
1663 struct smack_known *skp;
1664 char temp[80];
1665 int i;
1666
1667 if (!smack_privileged(CAP_MAC_ADMIN))
1668 return -EPERM;
1669
1670 if (count >= sizeof(temp) || count == 0)
1671 return -EINVAL;
1672
1673 if (copy_from_user(temp, buf, count) != 0)
1674 return -EFAULT;
1675
1676 temp[count] = '\0';
1677
1678 if (sscanf(temp, "%d", &i) != 1)
1679 return -EINVAL;
1680
1681 /*
1682 * Don't do anything if the value hasn't actually changed.
1683 * If it is changing reset the level on entries that were
1684 * set up to be direct when they were created.
1685 */
1686 if (smack_cipso_direct != i) {
1687 mutex_lock(&smack_known_lock);
1688 list_for_each_entry_rcu(skp, &smack_known_list, list)
1689 if (skp->smk_netlabel.attr.mls.lvl ==
1690 smack_cipso_direct)
1691 skp->smk_netlabel.attr.mls.lvl = i;
1692 smack_cipso_direct = i;
1693 mutex_unlock(&smack_known_lock);
1694 }
1695
1696 return count;
1697 }
1698
1699 static const struct file_operations smk_direct_ops = {
1700 .read = smk_read_direct,
1701 .write = smk_write_direct,
1702 .llseek = default_llseek,
1703 };
1704
1705 /**
1706 * smk_read_mapped - read() for /smack/mapped
1707 * @filp: file pointer, not actually used
1708 * @buf: where to put the result
1709 * @count: maximum to send along
1710 * @ppos: where to start
1711 *
1712 * Returns number of bytes read or error code, as appropriate
1713 */
smk_read_mapped(struct file * filp,char __user * buf,size_t count,loff_t * ppos)1714 static ssize_t smk_read_mapped(struct file *filp, char __user *buf,
1715 size_t count, loff_t *ppos)
1716 {
1717 char temp[80];
1718 ssize_t rc;
1719
1720 if (*ppos != 0)
1721 return 0;
1722
1723 sprintf(temp, "%d", smack_cipso_mapped);
1724 rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
1725
1726 return rc;
1727 }
1728
1729 /**
1730 * smk_write_mapped - write() for /smack/mapped
1731 * @file: file pointer, not actually used
1732 * @buf: where to get the data from
1733 * @count: bytes sent
1734 * @ppos: where to start
1735 *
1736 * Returns number of bytes written or error code, as appropriate
1737 */
smk_write_mapped(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1738 static ssize_t smk_write_mapped(struct file *file, const char __user *buf,
1739 size_t count, loff_t *ppos)
1740 {
1741 struct smack_known *skp;
1742 char temp[80];
1743 int i;
1744
1745 if (!smack_privileged(CAP_MAC_ADMIN))
1746 return -EPERM;
1747
1748 if (count >= sizeof(temp) || count == 0)
1749 return -EINVAL;
1750
1751 if (copy_from_user(temp, buf, count) != 0)
1752 return -EFAULT;
1753
1754 temp[count] = '\0';
1755
1756 if (sscanf(temp, "%d", &i) != 1)
1757 return -EINVAL;
1758
1759 /*
1760 * Don't do anything if the value hasn't actually changed.
1761 * If it is changing reset the level on entries that were
1762 * set up to be mapped when they were created.
1763 */
1764 if (smack_cipso_mapped != i) {
1765 mutex_lock(&smack_known_lock);
1766 list_for_each_entry_rcu(skp, &smack_known_list, list)
1767 if (skp->smk_netlabel.attr.mls.lvl ==
1768 smack_cipso_mapped)
1769 skp->smk_netlabel.attr.mls.lvl = i;
1770 smack_cipso_mapped = i;
1771 mutex_unlock(&smack_known_lock);
1772 }
1773
1774 return count;
1775 }
1776
1777 static const struct file_operations smk_mapped_ops = {
1778 .read = smk_read_mapped,
1779 .write = smk_write_mapped,
1780 .llseek = default_llseek,
1781 };
1782
1783 /**
1784 * smk_read_ambient - read() for /smack/ambient
1785 * @filp: file pointer, not actually used
1786 * @buf: where to put the result
1787 * @cn: maximum to send along
1788 * @ppos: where to start
1789 *
1790 * Returns number of bytes read or error code, as appropriate
1791 */
smk_read_ambient(struct file * filp,char __user * buf,size_t cn,loff_t * ppos)1792 static ssize_t smk_read_ambient(struct file *filp, char __user *buf,
1793 size_t cn, loff_t *ppos)
1794 {
1795 ssize_t rc;
1796 int asize;
1797
1798 if (*ppos != 0)
1799 return 0;
1800 /*
1801 * Being careful to avoid a problem in the case where
1802 * smack_net_ambient gets changed in midstream.
1803 */
1804 mutex_lock(&smack_ambient_lock);
1805
1806 asize = strlen(smack_net_ambient->smk_known) + 1;
1807
1808 if (cn >= asize)
1809 rc = simple_read_from_buffer(buf, cn, ppos,
1810 smack_net_ambient->smk_known,
1811 asize);
1812 else
1813 rc = -EINVAL;
1814
1815 mutex_unlock(&smack_ambient_lock);
1816
1817 return rc;
1818 }
1819
1820 /**
1821 * smk_write_ambient - write() for /smack/ambient
1822 * @file: file pointer, not actually used
1823 * @buf: where to get the data from
1824 * @count: bytes sent
1825 * @ppos: where to start
1826 *
1827 * Returns number of bytes written or error code, as appropriate
1828 */
smk_write_ambient(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1829 static ssize_t smk_write_ambient(struct file *file, const char __user *buf,
1830 size_t count, loff_t *ppos)
1831 {
1832 struct smack_known *skp;
1833 char *oldambient;
1834 char *data;
1835 int rc = count;
1836
1837 if (!smack_privileged(CAP_MAC_ADMIN))
1838 return -EPERM;
1839
1840 /* Enough data must be present */
1841 if (count == 0 || count > PAGE_SIZE)
1842 return -EINVAL;
1843
1844 data = memdup_user_nul(buf, count);
1845 if (IS_ERR(data))
1846 return PTR_ERR(data);
1847
1848 skp = smk_import_entry(data, count);
1849 if (IS_ERR(skp)) {
1850 rc = PTR_ERR(skp);
1851 goto out;
1852 }
1853
1854 mutex_lock(&smack_ambient_lock);
1855
1856 oldambient = smack_net_ambient->smk_known;
1857 smack_net_ambient = skp;
1858 smk_unlbl_ambient(oldambient);
1859
1860 mutex_unlock(&smack_ambient_lock);
1861
1862 out:
1863 kfree(data);
1864 return rc;
1865 }
1866
1867 static const struct file_operations smk_ambient_ops = {
1868 .read = smk_read_ambient,
1869 .write = smk_write_ambient,
1870 .llseek = default_llseek,
1871 };
1872
1873 /*
1874 * Seq_file operations for /smack/onlycap
1875 */
onlycap_seq_start(struct seq_file * s,loff_t * pos)1876 static void *onlycap_seq_start(struct seq_file *s, loff_t *pos)
1877 {
1878 return smk_seq_start(s, pos, &smack_onlycap_list);
1879 }
1880
onlycap_seq_next(struct seq_file * s,void * v,loff_t * pos)1881 static void *onlycap_seq_next(struct seq_file *s, void *v, loff_t *pos)
1882 {
1883 return smk_seq_next(s, v, pos, &smack_onlycap_list);
1884 }
1885
onlycap_seq_show(struct seq_file * s,void * v)1886 static int onlycap_seq_show(struct seq_file *s, void *v)
1887 {
1888 struct list_head *list = v;
1889 struct smack_known_list_elem *sklep =
1890 list_entry_rcu(list, struct smack_known_list_elem, list);
1891
1892 seq_puts(s, sklep->smk_label->smk_known);
1893 seq_putc(s, ' ');
1894
1895 return 0;
1896 }
1897
1898 static const struct seq_operations onlycap_seq_ops = {
1899 .start = onlycap_seq_start,
1900 .next = onlycap_seq_next,
1901 .show = onlycap_seq_show,
1902 .stop = smk_seq_stop,
1903 };
1904
smk_open_onlycap(struct inode * inode,struct file * file)1905 static int smk_open_onlycap(struct inode *inode, struct file *file)
1906 {
1907 return seq_open(file, &onlycap_seq_ops);
1908 }
1909
1910 /**
1911 * smk_list_swap_rcu - swap public list with a private one in RCU-safe way
1912 * The caller must hold appropriate mutex to prevent concurrent modifications
1913 * to the public list.
1914 * Private list is assumed to be not accessible to other threads yet.
1915 *
1916 * @public: public list
1917 * @private: private list
1918 */
smk_list_swap_rcu(struct list_head * public,struct list_head * private)1919 static void smk_list_swap_rcu(struct list_head *public,
1920 struct list_head *private)
1921 {
1922 struct list_head *first, *last;
1923
1924 if (list_empty(public)) {
1925 list_splice_init_rcu(private, public, synchronize_rcu);
1926 } else {
1927 /* Remember public list before replacing it */
1928 first = public->next;
1929 last = public->prev;
1930
1931 /* Publish private list in place of public in RCU-safe way */
1932 private->prev->next = public;
1933 private->next->prev = public;
1934 rcu_assign_pointer(public->next, private->next);
1935 public->prev = private->prev;
1936
1937 synchronize_rcu();
1938
1939 /* When all readers are done with the old public list,
1940 * attach it in place of private */
1941 private->next = first;
1942 private->prev = last;
1943 first->prev = private;
1944 last->next = private;
1945 }
1946 }
1947
1948 /**
1949 * smk_parse_label_list - parse list of Smack labels, separated by spaces
1950 *
1951 * @data: the string to parse
1952 * @private: destination list
1953 *
1954 * Returns zero on success or error code, as appropriate
1955 */
smk_parse_label_list(char * data,struct list_head * list)1956 static int smk_parse_label_list(char *data, struct list_head *list)
1957 {
1958 char *tok;
1959 struct smack_known *skp;
1960 struct smack_known_list_elem *sklep;
1961
1962 while ((tok = strsep(&data, " ")) != NULL) {
1963 if (!*tok)
1964 continue;
1965
1966 skp = smk_import_entry(tok, 0);
1967 if (IS_ERR(skp))
1968 return PTR_ERR(skp);
1969
1970 sklep = kzalloc(sizeof(*sklep), GFP_KERNEL);
1971 if (sklep == NULL)
1972 return -ENOMEM;
1973
1974 sklep->smk_label = skp;
1975 list_add(&sklep->list, list);
1976 }
1977
1978 return 0;
1979 }
1980
1981 /**
1982 * smk_destroy_label_list - destroy a list of smack_known_list_elem
1983 * @head: header pointer of the list to destroy
1984 */
smk_destroy_label_list(struct list_head * list)1985 void smk_destroy_label_list(struct list_head *list)
1986 {
1987 struct smack_known_list_elem *sklep;
1988 struct smack_known_list_elem *sklep2;
1989
1990 list_for_each_entry_safe(sklep, sklep2, list, list)
1991 kfree(sklep);
1992
1993 INIT_LIST_HEAD(list);
1994 }
1995
1996 /**
1997 * smk_write_onlycap - write() for smackfs/onlycap
1998 * @file: file pointer, not actually used
1999 * @buf: where to get the data from
2000 * @count: bytes sent
2001 * @ppos: where to start
2002 *
2003 * Returns number of bytes written or error code, as appropriate
2004 */
smk_write_onlycap(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2005 static ssize_t smk_write_onlycap(struct file *file, const char __user *buf,
2006 size_t count, loff_t *ppos)
2007 {
2008 char *data;
2009 LIST_HEAD(list_tmp);
2010 int rc;
2011
2012 if (!smack_privileged(CAP_MAC_ADMIN))
2013 return -EPERM;
2014
2015 if (count > PAGE_SIZE)
2016 return -EINVAL;
2017
2018 data = memdup_user_nul(buf, count);
2019 if (IS_ERR(data))
2020 return PTR_ERR(data);
2021
2022 rc = smk_parse_label_list(data, &list_tmp);
2023 kfree(data);
2024
2025 /*
2026 * Clear the smack_onlycap on invalid label errors. This means
2027 * that we can pass a null string to unset the onlycap value.
2028 *
2029 * Importing will also reject a label beginning with '-',
2030 * so "-usecapabilities" will also work.
2031 *
2032 * But do so only on invalid label, not on system errors.
2033 * The invalid label must be first to count as clearing attempt.
2034 */
2035 if (!rc || (rc == -EINVAL && list_empty(&list_tmp))) {
2036 mutex_lock(&smack_onlycap_lock);
2037 smk_list_swap_rcu(&smack_onlycap_list, &list_tmp);
2038 mutex_unlock(&smack_onlycap_lock);
2039 rc = count;
2040 }
2041
2042 smk_destroy_label_list(&list_tmp);
2043
2044 return rc;
2045 }
2046
2047 static const struct file_operations smk_onlycap_ops = {
2048 .open = smk_open_onlycap,
2049 .read = seq_read,
2050 .write = smk_write_onlycap,
2051 .llseek = seq_lseek,
2052 .release = seq_release,
2053 };
2054
2055 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
2056 /**
2057 * smk_read_unconfined - read() for smackfs/unconfined
2058 * @filp: file pointer, not actually used
2059 * @buf: where to put the result
2060 * @cn: maximum to send along
2061 * @ppos: where to start
2062 *
2063 * Returns number of bytes read or error code, as appropriate
2064 */
smk_read_unconfined(struct file * filp,char __user * buf,size_t cn,loff_t * ppos)2065 static ssize_t smk_read_unconfined(struct file *filp, char __user *buf,
2066 size_t cn, loff_t *ppos)
2067 {
2068 char *smack = "";
2069 ssize_t rc = -EINVAL;
2070 int asize;
2071
2072 if (*ppos != 0)
2073 return 0;
2074
2075 if (smack_unconfined != NULL)
2076 smack = smack_unconfined->smk_known;
2077
2078 asize = strlen(smack) + 1;
2079
2080 if (cn >= asize)
2081 rc = simple_read_from_buffer(buf, cn, ppos, smack, asize);
2082
2083 return rc;
2084 }
2085
2086 /**
2087 * smk_write_unconfined - write() for smackfs/unconfined
2088 * @file: file pointer, not actually used
2089 * @buf: where to get the data from
2090 * @count: bytes sent
2091 * @ppos: where to start
2092 *
2093 * Returns number of bytes written or error code, as appropriate
2094 */
smk_write_unconfined(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2095 static ssize_t smk_write_unconfined(struct file *file, const char __user *buf,
2096 size_t count, loff_t *ppos)
2097 {
2098 char *data;
2099 struct smack_known *skp;
2100 int rc = count;
2101
2102 if (!smack_privileged(CAP_MAC_ADMIN))
2103 return -EPERM;
2104
2105 if (count > PAGE_SIZE)
2106 return -EINVAL;
2107
2108 data = memdup_user_nul(buf, count);
2109 if (IS_ERR(data))
2110 return PTR_ERR(data);
2111
2112 /*
2113 * Clear the smack_unconfined on invalid label errors. This means
2114 * that we can pass a null string to unset the unconfined value.
2115 *
2116 * Importing will also reject a label beginning with '-',
2117 * so "-confine" will also work.
2118 *
2119 * But do so only on invalid label, not on system errors.
2120 */
2121 skp = smk_import_entry(data, count);
2122 if (PTR_ERR(skp) == -EINVAL)
2123 skp = NULL;
2124 else if (IS_ERR(skp)) {
2125 rc = PTR_ERR(skp);
2126 goto freeout;
2127 }
2128
2129 smack_unconfined = skp;
2130
2131 freeout:
2132 kfree(data);
2133 return rc;
2134 }
2135
2136 static const struct file_operations smk_unconfined_ops = {
2137 .read = smk_read_unconfined,
2138 .write = smk_write_unconfined,
2139 .llseek = default_llseek,
2140 };
2141 #endif /* CONFIG_SECURITY_SMACK_BRINGUP */
2142
2143 /**
2144 * smk_read_logging - read() for /smack/logging
2145 * @filp: file pointer, not actually used
2146 * @buf: where to put the result
2147 * @cn: maximum to send along
2148 * @ppos: where to start
2149 *
2150 * Returns number of bytes read or error code, as appropriate
2151 */
smk_read_logging(struct file * filp,char __user * buf,size_t count,loff_t * ppos)2152 static ssize_t smk_read_logging(struct file *filp, char __user *buf,
2153 size_t count, loff_t *ppos)
2154 {
2155 char temp[32];
2156 ssize_t rc;
2157
2158 if (*ppos != 0)
2159 return 0;
2160
2161 sprintf(temp, "%d\n", log_policy);
2162 rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
2163 return rc;
2164 }
2165
2166 /**
2167 * smk_write_logging - write() for /smack/logging
2168 * @file: file pointer, not actually used
2169 * @buf: where to get the data from
2170 * @count: bytes sent
2171 * @ppos: where to start
2172 *
2173 * Returns number of bytes written or error code, as appropriate
2174 */
smk_write_logging(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2175 static ssize_t smk_write_logging(struct file *file, const char __user *buf,
2176 size_t count, loff_t *ppos)
2177 {
2178 char temp[32];
2179 int i;
2180
2181 if (!smack_privileged(CAP_MAC_ADMIN))
2182 return -EPERM;
2183
2184 if (count >= sizeof(temp) || count == 0)
2185 return -EINVAL;
2186
2187 if (copy_from_user(temp, buf, count) != 0)
2188 return -EFAULT;
2189
2190 temp[count] = '\0';
2191
2192 if (sscanf(temp, "%d", &i) != 1)
2193 return -EINVAL;
2194 if (i < 0 || i > 3)
2195 return -EINVAL;
2196 log_policy = i;
2197 return count;
2198 }
2199
2200
2201
2202 static const struct file_operations smk_logging_ops = {
2203 .read = smk_read_logging,
2204 .write = smk_write_logging,
2205 .llseek = default_llseek,
2206 };
2207
2208 /*
2209 * Seq_file read operations for /smack/load-self
2210 */
2211
load_self_seq_start(struct seq_file * s,loff_t * pos)2212 static void *load_self_seq_start(struct seq_file *s, loff_t *pos)
2213 {
2214 struct task_smack *tsp = smack_cred(current_cred());
2215
2216 return smk_seq_start(s, pos, &tsp->smk_rules);
2217 }
2218
load_self_seq_next(struct seq_file * s,void * v,loff_t * pos)2219 static void *load_self_seq_next(struct seq_file *s, void *v, loff_t *pos)
2220 {
2221 struct task_smack *tsp = smack_cred(current_cred());
2222
2223 return smk_seq_next(s, v, pos, &tsp->smk_rules);
2224 }
2225
load_self_seq_show(struct seq_file * s,void * v)2226 static int load_self_seq_show(struct seq_file *s, void *v)
2227 {
2228 struct list_head *list = v;
2229 struct smack_rule *srp =
2230 list_entry_rcu(list, struct smack_rule, list);
2231
2232 smk_rule_show(s, srp, SMK_LABELLEN);
2233
2234 return 0;
2235 }
2236
2237 static const struct seq_operations load_self_seq_ops = {
2238 .start = load_self_seq_start,
2239 .next = load_self_seq_next,
2240 .show = load_self_seq_show,
2241 .stop = smk_seq_stop,
2242 };
2243
2244
2245 /**
2246 * smk_open_load_self - open() for /smack/load-self2
2247 * @inode: inode structure representing file
2248 * @file: "load" file pointer
2249 *
2250 * For reading, use load_seq_* seq_file reading operations.
2251 */
smk_open_load_self(struct inode * inode,struct file * file)2252 static int smk_open_load_self(struct inode *inode, struct file *file)
2253 {
2254 return seq_open(file, &load_self_seq_ops);
2255 }
2256
2257 /**
2258 * smk_write_load_self - write() for /smack/load-self
2259 * @file: file pointer, not actually used
2260 * @buf: where to get the data from
2261 * @count: bytes sent
2262 * @ppos: where to start - must be 0
2263 *
2264 */
smk_write_load_self(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2265 static ssize_t smk_write_load_self(struct file *file, const char __user *buf,
2266 size_t count, loff_t *ppos)
2267 {
2268 struct task_smack *tsp = smack_cred(current_cred());
2269
2270 return smk_write_rules_list(file, buf, count, ppos, &tsp->smk_rules,
2271 &tsp->smk_rules_lock, SMK_FIXED24_FMT);
2272 }
2273
2274 static const struct file_operations smk_load_self_ops = {
2275 .open = smk_open_load_self,
2276 .read = seq_read,
2277 .llseek = seq_lseek,
2278 .write = smk_write_load_self,
2279 .release = seq_release,
2280 };
2281
2282 /**
2283 * smk_user_access - handle access check transaction
2284 * @file: file pointer
2285 * @buf: data from user space
2286 * @count: bytes sent
2287 * @ppos: where to start - must be 0
2288 */
smk_user_access(struct file * file,const char __user * buf,size_t count,loff_t * ppos,int format)2289 static ssize_t smk_user_access(struct file *file, const char __user *buf,
2290 size_t count, loff_t *ppos, int format)
2291 {
2292 struct smack_parsed_rule rule;
2293 char *data;
2294 int res;
2295
2296 data = simple_transaction_get(file, buf, count);
2297 if (IS_ERR(data))
2298 return PTR_ERR(data);
2299
2300 if (format == SMK_FIXED24_FMT) {
2301 if (count < SMK_LOADLEN)
2302 return -EINVAL;
2303 res = smk_parse_rule(data, &rule, 0);
2304 } else {
2305 /*
2306 * simple_transaction_get() returns null-terminated data
2307 */
2308 res = smk_parse_long_rule(data, &rule, 0, 3);
2309 }
2310
2311 if (res >= 0)
2312 res = smk_access(rule.smk_subject, rule.smk_object,
2313 rule.smk_access1, NULL);
2314 else if (res != -ENOENT)
2315 return res;
2316
2317 /*
2318 * smk_access() can return a value > 0 in the "bringup" case.
2319 */
2320 data[0] = res >= 0 ? '1' : '0';
2321 data[1] = '\0';
2322
2323 simple_transaction_set(file, 2);
2324
2325 if (format == SMK_FIXED24_FMT)
2326 return SMK_LOADLEN;
2327 return count;
2328 }
2329
2330 /**
2331 * smk_write_access - handle access check transaction
2332 * @file: file pointer
2333 * @buf: data from user space
2334 * @count: bytes sent
2335 * @ppos: where to start - must be 0
2336 */
smk_write_access(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2337 static ssize_t smk_write_access(struct file *file, const char __user *buf,
2338 size_t count, loff_t *ppos)
2339 {
2340 return smk_user_access(file, buf, count, ppos, SMK_FIXED24_FMT);
2341 }
2342
2343 static const struct file_operations smk_access_ops = {
2344 .write = smk_write_access,
2345 .read = simple_transaction_read,
2346 .release = simple_transaction_release,
2347 .llseek = generic_file_llseek,
2348 };
2349
2350
2351 /*
2352 * Seq_file read operations for /smack/load2
2353 */
2354
load2_seq_show(struct seq_file * s,void * v)2355 static int load2_seq_show(struct seq_file *s, void *v)
2356 {
2357 struct list_head *list = v;
2358 struct smack_rule *srp;
2359 struct smack_known *skp =
2360 list_entry_rcu(list, struct smack_known, list);
2361
2362 list_for_each_entry_rcu(srp, &skp->smk_rules, list)
2363 smk_rule_show(s, srp, SMK_LONGLABEL);
2364
2365 return 0;
2366 }
2367
2368 static const struct seq_operations load2_seq_ops = {
2369 .start = load2_seq_start,
2370 .next = load2_seq_next,
2371 .show = load2_seq_show,
2372 .stop = smk_seq_stop,
2373 };
2374
2375 /**
2376 * smk_open_load2 - open() for /smack/load2
2377 * @inode: inode structure representing file
2378 * @file: "load2" file pointer
2379 *
2380 * For reading, use load2_seq_* seq_file reading operations.
2381 */
smk_open_load2(struct inode * inode,struct file * file)2382 static int smk_open_load2(struct inode *inode, struct file *file)
2383 {
2384 return seq_open(file, &load2_seq_ops);
2385 }
2386
2387 /**
2388 * smk_write_load2 - write() for /smack/load2
2389 * @file: file pointer, not actually used
2390 * @buf: where to get the data from
2391 * @count: bytes sent
2392 * @ppos: where to start - must be 0
2393 *
2394 */
smk_write_load2(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2395 static ssize_t smk_write_load2(struct file *file, const char __user *buf,
2396 size_t count, loff_t *ppos)
2397 {
2398 /*
2399 * Must have privilege.
2400 */
2401 if (!smack_privileged(CAP_MAC_ADMIN))
2402 return -EPERM;
2403
2404 return smk_write_rules_list(file, buf, count, ppos, NULL, NULL,
2405 SMK_LONG_FMT);
2406 }
2407
2408 static const struct file_operations smk_load2_ops = {
2409 .open = smk_open_load2,
2410 .read = seq_read,
2411 .llseek = seq_lseek,
2412 .write = smk_write_load2,
2413 .release = seq_release,
2414 };
2415
2416 /*
2417 * Seq_file read operations for /smack/load-self2
2418 */
2419
load_self2_seq_start(struct seq_file * s,loff_t * pos)2420 static void *load_self2_seq_start(struct seq_file *s, loff_t *pos)
2421 {
2422 struct task_smack *tsp = smack_cred(current_cred());
2423
2424 return smk_seq_start(s, pos, &tsp->smk_rules);
2425 }
2426
load_self2_seq_next(struct seq_file * s,void * v,loff_t * pos)2427 static void *load_self2_seq_next(struct seq_file *s, void *v, loff_t *pos)
2428 {
2429 struct task_smack *tsp = smack_cred(current_cred());
2430
2431 return smk_seq_next(s, v, pos, &tsp->smk_rules);
2432 }
2433
load_self2_seq_show(struct seq_file * s,void * v)2434 static int load_self2_seq_show(struct seq_file *s, void *v)
2435 {
2436 struct list_head *list = v;
2437 struct smack_rule *srp =
2438 list_entry_rcu(list, struct smack_rule, list);
2439
2440 smk_rule_show(s, srp, SMK_LONGLABEL);
2441
2442 return 0;
2443 }
2444
2445 static const struct seq_operations load_self2_seq_ops = {
2446 .start = load_self2_seq_start,
2447 .next = load_self2_seq_next,
2448 .show = load_self2_seq_show,
2449 .stop = smk_seq_stop,
2450 };
2451
2452 /**
2453 * smk_open_load_self2 - open() for /smack/load-self2
2454 * @inode: inode structure representing file
2455 * @file: "load" file pointer
2456 *
2457 * For reading, use load_seq_* seq_file reading operations.
2458 */
smk_open_load_self2(struct inode * inode,struct file * file)2459 static int smk_open_load_self2(struct inode *inode, struct file *file)
2460 {
2461 return seq_open(file, &load_self2_seq_ops);
2462 }
2463
2464 /**
2465 * smk_write_load_self2 - write() for /smack/load-self2
2466 * @file: file pointer, not actually used
2467 * @buf: where to get the data from
2468 * @count: bytes sent
2469 * @ppos: where to start - must be 0
2470 *
2471 */
smk_write_load_self2(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2472 static ssize_t smk_write_load_self2(struct file *file, const char __user *buf,
2473 size_t count, loff_t *ppos)
2474 {
2475 struct task_smack *tsp = smack_cred(current_cred());
2476
2477 return smk_write_rules_list(file, buf, count, ppos, &tsp->smk_rules,
2478 &tsp->smk_rules_lock, SMK_LONG_FMT);
2479 }
2480
2481 static const struct file_operations smk_load_self2_ops = {
2482 .open = smk_open_load_self2,
2483 .read = seq_read,
2484 .llseek = seq_lseek,
2485 .write = smk_write_load_self2,
2486 .release = seq_release,
2487 };
2488
2489 /**
2490 * smk_write_access2 - handle access check transaction
2491 * @file: file pointer
2492 * @buf: data from user space
2493 * @count: bytes sent
2494 * @ppos: where to start - must be 0
2495 */
smk_write_access2(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2496 static ssize_t smk_write_access2(struct file *file, const char __user *buf,
2497 size_t count, loff_t *ppos)
2498 {
2499 return smk_user_access(file, buf, count, ppos, SMK_LONG_FMT);
2500 }
2501
2502 static const struct file_operations smk_access2_ops = {
2503 .write = smk_write_access2,
2504 .read = simple_transaction_read,
2505 .release = simple_transaction_release,
2506 .llseek = generic_file_llseek,
2507 };
2508
2509 /**
2510 * smk_write_revoke_subj - write() for /smack/revoke-subject
2511 * @file: file pointer
2512 * @buf: data from user space
2513 * @count: bytes sent
2514 * @ppos: where to start - must be 0
2515 */
smk_write_revoke_subj(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2516 static ssize_t smk_write_revoke_subj(struct file *file, const char __user *buf,
2517 size_t count, loff_t *ppos)
2518 {
2519 char *data;
2520 const char *cp;
2521 struct smack_known *skp;
2522 struct smack_rule *sp;
2523 struct list_head *rule_list;
2524 struct mutex *rule_lock;
2525 int rc = count;
2526
2527 if (*ppos != 0)
2528 return -EINVAL;
2529
2530 if (!smack_privileged(CAP_MAC_ADMIN))
2531 return -EPERM;
2532
2533 if (count == 0 || count > SMK_LONGLABEL)
2534 return -EINVAL;
2535
2536 data = memdup_user(buf, count);
2537 if (IS_ERR(data))
2538 return PTR_ERR(data);
2539
2540 cp = smk_parse_smack(data, count);
2541 if (IS_ERR(cp)) {
2542 rc = PTR_ERR(cp);
2543 goto out_data;
2544 }
2545
2546 skp = smk_find_entry(cp);
2547 if (skp == NULL)
2548 goto out_cp;
2549
2550 rule_list = &skp->smk_rules;
2551 rule_lock = &skp->smk_rules_lock;
2552
2553 mutex_lock(rule_lock);
2554
2555 list_for_each_entry_rcu(sp, rule_list, list)
2556 sp->smk_access = 0;
2557
2558 mutex_unlock(rule_lock);
2559
2560 out_cp:
2561 kfree(cp);
2562 out_data:
2563 kfree(data);
2564
2565 return rc;
2566 }
2567
2568 static const struct file_operations smk_revoke_subj_ops = {
2569 .write = smk_write_revoke_subj,
2570 .read = simple_transaction_read,
2571 .release = simple_transaction_release,
2572 .llseek = generic_file_llseek,
2573 };
2574
2575 /**
2576 * smk_init_sysfs - initialize /sys/fs/smackfs
2577 *
2578 */
smk_init_sysfs(void)2579 static int smk_init_sysfs(void)
2580 {
2581 return sysfs_create_mount_point(fs_kobj, "smackfs");
2582 }
2583
2584 /**
2585 * smk_write_change_rule - write() for /smack/change-rule
2586 * @file: file pointer
2587 * @buf: data from user space
2588 * @count: bytes sent
2589 * @ppos: where to start - must be 0
2590 */
smk_write_change_rule(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2591 static ssize_t smk_write_change_rule(struct file *file, const char __user *buf,
2592 size_t count, loff_t *ppos)
2593 {
2594 /*
2595 * Must have privilege.
2596 */
2597 if (!smack_privileged(CAP_MAC_ADMIN))
2598 return -EPERM;
2599
2600 return smk_write_rules_list(file, buf, count, ppos, NULL, NULL,
2601 SMK_CHANGE_FMT);
2602 }
2603
2604 static const struct file_operations smk_change_rule_ops = {
2605 .write = smk_write_change_rule,
2606 .read = simple_transaction_read,
2607 .release = simple_transaction_release,
2608 .llseek = generic_file_llseek,
2609 };
2610
2611 /**
2612 * smk_read_syslog - read() for smackfs/syslog
2613 * @filp: file pointer, not actually used
2614 * @buf: where to put the result
2615 * @cn: maximum to send along
2616 * @ppos: where to start
2617 *
2618 * Returns number of bytes read or error code, as appropriate
2619 */
smk_read_syslog(struct file * filp,char __user * buf,size_t cn,loff_t * ppos)2620 static ssize_t smk_read_syslog(struct file *filp, char __user *buf,
2621 size_t cn, loff_t *ppos)
2622 {
2623 struct smack_known *skp;
2624 ssize_t rc = -EINVAL;
2625 int asize;
2626
2627 if (*ppos != 0)
2628 return 0;
2629
2630 if (smack_syslog_label == NULL)
2631 skp = &smack_known_star;
2632 else
2633 skp = smack_syslog_label;
2634
2635 asize = strlen(skp->smk_known) + 1;
2636
2637 if (cn >= asize)
2638 rc = simple_read_from_buffer(buf, cn, ppos, skp->smk_known,
2639 asize);
2640
2641 return rc;
2642 }
2643
2644 /**
2645 * smk_write_syslog - write() for smackfs/syslog
2646 * @file: file pointer, not actually used
2647 * @buf: where to get the data from
2648 * @count: bytes sent
2649 * @ppos: where to start
2650 *
2651 * Returns number of bytes written or error code, as appropriate
2652 */
smk_write_syslog(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2653 static ssize_t smk_write_syslog(struct file *file, const char __user *buf,
2654 size_t count, loff_t *ppos)
2655 {
2656 char *data;
2657 struct smack_known *skp;
2658 int rc = count;
2659
2660 if (!smack_privileged(CAP_MAC_ADMIN))
2661 return -EPERM;
2662
2663 /* Enough data must be present */
2664 if (count == 0 || count > PAGE_SIZE)
2665 return -EINVAL;
2666
2667 data = memdup_user_nul(buf, count);
2668 if (IS_ERR(data))
2669 return PTR_ERR(data);
2670
2671 skp = smk_import_entry(data, count);
2672 if (IS_ERR(skp))
2673 rc = PTR_ERR(skp);
2674 else
2675 smack_syslog_label = skp;
2676
2677 kfree(data);
2678 return rc;
2679 }
2680
2681 static const struct file_operations smk_syslog_ops = {
2682 .read = smk_read_syslog,
2683 .write = smk_write_syslog,
2684 .llseek = default_llseek,
2685 };
2686
2687 /*
2688 * Seq_file read operations for /smack/relabel-self
2689 */
2690
relabel_self_seq_start(struct seq_file * s,loff_t * pos)2691 static void *relabel_self_seq_start(struct seq_file *s, loff_t *pos)
2692 {
2693 struct task_smack *tsp = smack_cred(current_cred());
2694
2695 return smk_seq_start(s, pos, &tsp->smk_relabel);
2696 }
2697
relabel_self_seq_next(struct seq_file * s,void * v,loff_t * pos)2698 static void *relabel_self_seq_next(struct seq_file *s, void *v, loff_t *pos)
2699 {
2700 struct task_smack *tsp = smack_cred(current_cred());
2701
2702 return smk_seq_next(s, v, pos, &tsp->smk_relabel);
2703 }
2704
relabel_self_seq_show(struct seq_file * s,void * v)2705 static int relabel_self_seq_show(struct seq_file *s, void *v)
2706 {
2707 struct list_head *list = v;
2708 struct smack_known_list_elem *sklep =
2709 list_entry(list, struct smack_known_list_elem, list);
2710
2711 seq_puts(s, sklep->smk_label->smk_known);
2712 seq_putc(s, ' ');
2713
2714 return 0;
2715 }
2716
2717 static const struct seq_operations relabel_self_seq_ops = {
2718 .start = relabel_self_seq_start,
2719 .next = relabel_self_seq_next,
2720 .show = relabel_self_seq_show,
2721 .stop = smk_seq_stop,
2722 };
2723
2724 /**
2725 * smk_open_relabel_self - open() for /smack/relabel-self
2726 * @inode: inode structure representing file
2727 * @file: "relabel-self" file pointer
2728 *
2729 * Connect our relabel_self_seq_* operations with /smack/relabel-self
2730 * file_operations
2731 */
smk_open_relabel_self(struct inode * inode,struct file * file)2732 static int smk_open_relabel_self(struct inode *inode, struct file *file)
2733 {
2734 return seq_open(file, &relabel_self_seq_ops);
2735 }
2736
2737 /**
2738 * smk_write_relabel_self - write() for /smack/relabel-self
2739 * @file: file pointer, not actually used
2740 * @buf: where to get the data from
2741 * @count: bytes sent
2742 * @ppos: where to start - must be 0
2743 *
2744 */
smk_write_relabel_self(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2745 static ssize_t smk_write_relabel_self(struct file *file, const char __user *buf,
2746 size_t count, loff_t *ppos)
2747 {
2748 char *data;
2749 int rc;
2750 LIST_HEAD(list_tmp);
2751
2752 /*
2753 * Must have privilege.
2754 */
2755 if (!smack_privileged(CAP_MAC_ADMIN))
2756 return -EPERM;
2757
2758 /*
2759 * No partial write.
2760 * Enough data must be present.
2761 */
2762 if (*ppos != 0)
2763 return -EINVAL;
2764 if (count == 0 || count > PAGE_SIZE)
2765 return -EINVAL;
2766
2767 data = memdup_user_nul(buf, count);
2768 if (IS_ERR(data))
2769 return PTR_ERR(data);
2770
2771 rc = smk_parse_label_list(data, &list_tmp);
2772 kfree(data);
2773
2774 if (!rc || (rc == -EINVAL && list_empty(&list_tmp))) {
2775 struct cred *new;
2776 struct task_smack *tsp;
2777
2778 new = prepare_creds();
2779 if (!new) {
2780 rc = -ENOMEM;
2781 goto out;
2782 }
2783 tsp = smack_cred(new);
2784 smk_destroy_label_list(&tsp->smk_relabel);
2785 list_splice(&list_tmp, &tsp->smk_relabel);
2786 commit_creds(new);
2787 return count;
2788 }
2789 out:
2790 smk_destroy_label_list(&list_tmp);
2791 return rc;
2792 }
2793
2794 static const struct file_operations smk_relabel_self_ops = {
2795 .open = smk_open_relabel_self,
2796 .read = seq_read,
2797 .llseek = seq_lseek,
2798 .write = smk_write_relabel_self,
2799 .release = seq_release,
2800 };
2801
2802 /**
2803 * smk_read_ptrace - read() for /smack/ptrace
2804 * @filp: file pointer, not actually used
2805 * @buf: where to put the result
2806 * @count: maximum to send along
2807 * @ppos: where to start
2808 *
2809 * Returns number of bytes read or error code, as appropriate
2810 */
smk_read_ptrace(struct file * filp,char __user * buf,size_t count,loff_t * ppos)2811 static ssize_t smk_read_ptrace(struct file *filp, char __user *buf,
2812 size_t count, loff_t *ppos)
2813 {
2814 char temp[32];
2815 ssize_t rc;
2816
2817 if (*ppos != 0)
2818 return 0;
2819
2820 sprintf(temp, "%d\n", smack_ptrace_rule);
2821 rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
2822 return rc;
2823 }
2824
2825 /**
2826 * smk_write_ptrace - write() for /smack/ptrace
2827 * @file: file pointer
2828 * @buf: data from user space
2829 * @count: bytes sent
2830 * @ppos: where to start - must be 0
2831 */
smk_write_ptrace(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2832 static ssize_t smk_write_ptrace(struct file *file, const char __user *buf,
2833 size_t count, loff_t *ppos)
2834 {
2835 char temp[32];
2836 int i;
2837
2838 if (!smack_privileged(CAP_MAC_ADMIN))
2839 return -EPERM;
2840
2841 if (*ppos != 0 || count >= sizeof(temp) || count == 0)
2842 return -EINVAL;
2843
2844 if (copy_from_user(temp, buf, count) != 0)
2845 return -EFAULT;
2846
2847 temp[count] = '\0';
2848
2849 if (sscanf(temp, "%d", &i) != 1)
2850 return -EINVAL;
2851 if (i < SMACK_PTRACE_DEFAULT || i > SMACK_PTRACE_MAX)
2852 return -EINVAL;
2853 smack_ptrace_rule = i;
2854
2855 return count;
2856 }
2857
2858 static const struct file_operations smk_ptrace_ops = {
2859 .write = smk_write_ptrace,
2860 .read = smk_read_ptrace,
2861 .llseek = default_llseek,
2862 };
2863
2864 /**
2865 * smk_fill_super - fill the smackfs superblock
2866 * @sb: the empty superblock
2867 * @fc: unused
2868 *
2869 * Fill in the well known entries for the smack filesystem
2870 *
2871 * Returns 0 on success, an error code on failure
2872 */
smk_fill_super(struct super_block * sb,struct fs_context * fc)2873 static int smk_fill_super(struct super_block *sb, struct fs_context *fc)
2874 {
2875 int rc;
2876
2877 static const struct tree_descr smack_files[] = {
2878 [SMK_LOAD] = {
2879 "load", &smk_load_ops, S_IRUGO|S_IWUSR},
2880 [SMK_CIPSO] = {
2881 "cipso", &smk_cipso_ops, S_IRUGO|S_IWUSR},
2882 [SMK_DOI] = {
2883 "doi", &smk_doi_ops, S_IRUGO|S_IWUSR},
2884 [SMK_DIRECT] = {
2885 "direct", &smk_direct_ops, S_IRUGO|S_IWUSR},
2886 [SMK_AMBIENT] = {
2887 "ambient", &smk_ambient_ops, S_IRUGO|S_IWUSR},
2888 [SMK_NET4ADDR] = {
2889 "netlabel", &smk_net4addr_ops, S_IRUGO|S_IWUSR},
2890 [SMK_ONLYCAP] = {
2891 "onlycap", &smk_onlycap_ops, S_IRUGO|S_IWUSR},
2892 [SMK_LOGGING] = {
2893 "logging", &smk_logging_ops, S_IRUGO|S_IWUSR},
2894 [SMK_LOAD_SELF] = {
2895 "load-self", &smk_load_self_ops, S_IRUGO|S_IWUGO},
2896 [SMK_ACCESSES] = {
2897 "access", &smk_access_ops, S_IRUGO|S_IWUGO},
2898 [SMK_MAPPED] = {
2899 "mapped", &smk_mapped_ops, S_IRUGO|S_IWUSR},
2900 [SMK_LOAD2] = {
2901 "load2", &smk_load2_ops, S_IRUGO|S_IWUSR},
2902 [SMK_LOAD_SELF2] = {
2903 "load-self2", &smk_load_self2_ops, S_IRUGO|S_IWUGO},
2904 [SMK_ACCESS2] = {
2905 "access2", &smk_access2_ops, S_IRUGO|S_IWUGO},
2906 [SMK_CIPSO2] = {
2907 "cipso2", &smk_cipso2_ops, S_IRUGO|S_IWUSR},
2908 [SMK_REVOKE_SUBJ] = {
2909 "revoke-subject", &smk_revoke_subj_ops,
2910 S_IRUGO|S_IWUSR},
2911 [SMK_CHANGE_RULE] = {
2912 "change-rule", &smk_change_rule_ops, S_IRUGO|S_IWUSR},
2913 [SMK_SYSLOG] = {
2914 "syslog", &smk_syslog_ops, S_IRUGO|S_IWUSR},
2915 [SMK_PTRACE] = {
2916 "ptrace", &smk_ptrace_ops, S_IRUGO|S_IWUSR},
2917 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
2918 [SMK_UNCONFINED] = {
2919 "unconfined", &smk_unconfined_ops, S_IRUGO|S_IWUSR},
2920 #endif
2921 #if IS_ENABLED(CONFIG_IPV6)
2922 [SMK_NET6ADDR] = {
2923 "ipv6host", &smk_net6addr_ops, S_IRUGO|S_IWUSR},
2924 #endif /* CONFIG_IPV6 */
2925 [SMK_RELABEL_SELF] = {
2926 "relabel-self", &smk_relabel_self_ops,
2927 S_IRUGO|S_IWUGO},
2928 /* last one */
2929 {""}
2930 };
2931
2932 rc = simple_fill_super(sb, SMACK_MAGIC, smack_files);
2933 if (rc != 0) {
2934 printk(KERN_ERR "%s failed %d while creating inodes\n",
2935 __func__, rc);
2936 return rc;
2937 }
2938
2939 return 0;
2940 }
2941
2942 /**
2943 * smk_get_tree - get the smackfs superblock
2944 * @fc: The mount context, including any options
2945 *
2946 * Just passes everything along.
2947 *
2948 * Returns what the lower level code does.
2949 */
smk_get_tree(struct fs_context * fc)2950 static int smk_get_tree(struct fs_context *fc)
2951 {
2952 return get_tree_single(fc, smk_fill_super);
2953 }
2954
2955 static const struct fs_context_operations smk_context_ops = {
2956 .get_tree = smk_get_tree,
2957 };
2958
2959 /**
2960 * smk_init_fs_context - Initialise a filesystem context for smackfs
2961 * @fc: The blank mount context
2962 */
smk_init_fs_context(struct fs_context * fc)2963 static int smk_init_fs_context(struct fs_context *fc)
2964 {
2965 fc->ops = &smk_context_ops;
2966 return 0;
2967 }
2968
2969 static struct file_system_type smk_fs_type = {
2970 .name = "smackfs",
2971 .init_fs_context = smk_init_fs_context,
2972 .kill_sb = kill_litter_super,
2973 };
2974
2975 static struct vfsmount *smackfs_mount;
2976
2977 /**
2978 * init_smk_fs - get the smackfs superblock
2979 *
2980 * register the smackfs
2981 *
2982 * Do not register smackfs if Smack wasn't enabled
2983 * on boot. We can not put this method normally under the
2984 * smack_init() code path since the security subsystem get
2985 * initialized before the vfs caches.
2986 *
2987 * Returns true if we were not chosen on boot or if
2988 * we were chosen and filesystem registration succeeded.
2989 */
init_smk_fs(void)2990 static int __init init_smk_fs(void)
2991 {
2992 int err;
2993 int rc;
2994
2995 if (smack_enabled == 0)
2996 return 0;
2997
2998 err = smk_init_sysfs();
2999 if (err)
3000 printk(KERN_ERR "smackfs: sysfs mountpoint problem.\n");
3001
3002 err = register_filesystem(&smk_fs_type);
3003 if (!err) {
3004 smackfs_mount = kern_mount(&smk_fs_type);
3005 if (IS_ERR(smackfs_mount)) {
3006 printk(KERN_ERR "smackfs: could not mount!\n");
3007 err = PTR_ERR(smackfs_mount);
3008 smackfs_mount = NULL;
3009 }
3010 }
3011
3012 smk_cipso_doi();
3013 smk_unlbl_ambient(NULL);
3014
3015 rc = smack_populate_secattr(&smack_known_floor);
3016 if (err == 0 && rc < 0)
3017 err = rc;
3018 rc = smack_populate_secattr(&smack_known_hat);
3019 if (err == 0 && rc < 0)
3020 err = rc;
3021 rc = smack_populate_secattr(&smack_known_huh);
3022 if (err == 0 && rc < 0)
3023 err = rc;
3024 rc = smack_populate_secattr(&smack_known_star);
3025 if (err == 0 && rc < 0)
3026 err = rc;
3027 rc = smack_populate_secattr(&smack_known_web);
3028 if (err == 0 && rc < 0)
3029 err = rc;
3030
3031 return err;
3032 }
3033
3034 __initcall(init_smk_fs);
3035