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/mount.h>
27 #include <linux/fs_context.h>
28 #include "smack.h"
29
30 #define BEBITS (sizeof(__be32) * 8)
31 /*
32 * smackfs pseudo filesystem.
33 */
34
35 enum smk_inos {
36 SMK_ROOT_INO = 2,
37 SMK_LOAD = 3, /* load policy */
38 SMK_CIPSO = 4, /* load label -> CIPSO mapping */
39 SMK_DOI = 5, /* CIPSO DOI */
40 SMK_DIRECT = 6, /* CIPSO level indicating direct label */
41 SMK_AMBIENT = 7, /* internet ambient label */
42 SMK_NET4ADDR = 8, /* single label hosts */
43 SMK_ONLYCAP = 9, /* the only "capable" label */
44 SMK_LOGGING = 10, /* logging */
45 SMK_LOAD_SELF = 11, /* task specific rules */
46 SMK_ACCESSES = 12, /* access policy */
47 SMK_MAPPED = 13, /* CIPSO level indicating mapped label */
48 SMK_LOAD2 = 14, /* load policy with long labels */
49 SMK_LOAD_SELF2 = 15, /* load task specific rules with long labels */
50 SMK_ACCESS2 = 16, /* make an access check with long labels */
51 SMK_CIPSO2 = 17, /* load long label -> CIPSO mapping */
52 SMK_REVOKE_SUBJ = 18, /* set rules with subject label to '-' */
53 SMK_CHANGE_RULE = 19, /* change or add rules (long labels) */
54 SMK_SYSLOG = 20, /* change syslog label) */
55 SMK_PTRACE = 21, /* set ptrace rule */
56 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
57 SMK_UNCONFINED = 22, /* define an unconfined label */
58 #endif
59 #if IS_ENABLED(CONFIG_IPV6)
60 SMK_NET6ADDR = 23, /* single label IPv6 hosts */
61 #endif /* CONFIG_IPV6 */
62 SMK_RELABEL_SELF = 24, /* relabel possible without CAP_MAC_ADMIN */
63 };
64
65 /*
66 * List locks
67 */
68 static DEFINE_MUTEX(smack_cipso_lock);
69 static DEFINE_MUTEX(smack_ambient_lock);
70 static DEFINE_MUTEX(smk_net4addr_lock);
71 #if IS_ENABLED(CONFIG_IPV6)
72 static DEFINE_MUTEX(smk_net6addr_lock);
73 #endif /* CONFIG_IPV6 */
74
75 /*
76 * This is the "ambient" label for network traffic.
77 * If it isn't somehow marked, use this.
78 * It can be reset via smackfs/ambient
79 */
80 struct smack_known *smack_net_ambient;
81
82 /*
83 * This is the level in a CIPSO header that indicates a
84 * smack label is contained directly in the category set.
85 * It can be reset via smackfs/direct
86 */
87 int smack_cipso_direct = SMACK_CIPSO_DIRECT_DEFAULT;
88
89 /*
90 * This is the level in a CIPSO header that indicates a
91 * secid is contained directly in the category set.
92 * It can be reset via smackfs/mapped
93 */
94 int smack_cipso_mapped = SMACK_CIPSO_MAPPED_DEFAULT;
95
96 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
97 /*
98 * Allow one label to be unconfined. This is for
99 * debugging and application bring-up purposes only.
100 * It is bad and wrong, but everyone seems to expect
101 * to have it.
102 */
103 struct smack_known *smack_unconfined;
104 #endif
105
106 /*
107 * If this value is set restrict syslog use to the label specified.
108 * It can be reset via smackfs/syslog
109 */
110 struct smack_known *smack_syslog_label;
111
112 /*
113 * Ptrace current rule
114 * SMACK_PTRACE_DEFAULT regular smack ptrace rules (/proc based)
115 * SMACK_PTRACE_EXACT labels must match, but can be overriden with
116 * CAP_SYS_PTRACE
117 * SMACK_PTRACE_DRACONIAN labels must match, CAP_SYS_PTRACE has no effect
118 */
119 int smack_ptrace_rule = SMACK_PTRACE_DEFAULT;
120
121 /*
122 * Certain IP addresses may be designated as single label hosts.
123 * Packets are sent there unlabeled, but only from tasks that
124 * can write to the specified label.
125 */
126
127 LIST_HEAD(smk_net4addr_list);
128 #if IS_ENABLED(CONFIG_IPV6)
129 LIST_HEAD(smk_net6addr_list);
130 #endif /* CONFIG_IPV6 */
131
132 /*
133 * Rule lists are maintained for each label.
134 */
135 struct smack_parsed_rule {
136 struct smack_known *smk_subject;
137 struct smack_known *smk_object;
138 int smk_access1;
139 int smk_access2;
140 };
141
142 static int smk_cipso_doi_value = SMACK_CIPSO_DOI_DEFAULT;
143
144 /*
145 * Values for parsing cipso rules
146 * SMK_DIGITLEN: Length of a digit field in a rule.
147 * SMK_CIPSOMIN: Minimum possible cipso rule length.
148 * SMK_CIPSOMAX: Maximum possible cipso rule length.
149 */
150 #define SMK_DIGITLEN 4
151 #define SMK_CIPSOMIN (SMK_LABELLEN + 2 * SMK_DIGITLEN)
152 #define SMK_CIPSOMAX (SMK_CIPSOMIN + SMACK_CIPSO_MAXCATNUM * SMK_DIGITLEN)
153
154 /*
155 * Values for parsing MAC rules
156 * SMK_ACCESS: Maximum possible combination of access permissions
157 * SMK_ACCESSLEN: Maximum length for a rule access field
158 * SMK_LOADLEN: Smack rule length
159 */
160 #define SMK_OACCESS "rwxa"
161 #define SMK_ACCESS "rwxatl"
162 #define SMK_OACCESSLEN (sizeof(SMK_OACCESS) - 1)
163 #define SMK_ACCESSLEN (sizeof(SMK_ACCESS) - 1)
164 #define SMK_OLOADLEN (SMK_LABELLEN + SMK_LABELLEN + SMK_OACCESSLEN)
165 #define SMK_LOADLEN (SMK_LABELLEN + SMK_LABELLEN + SMK_ACCESSLEN)
166
167 /*
168 * Stricly for CIPSO level manipulation.
169 * Set the category bit number in a smack label sized buffer.
170 */
smack_catset_bit(unsigned int cat,char * catsetp)171 static inline void smack_catset_bit(unsigned int cat, char *catsetp)
172 {
173 if (cat == 0 || cat > (SMK_CIPSOLEN * 8))
174 return;
175
176 catsetp[(cat - 1) / 8] |= 0x80 >> ((cat - 1) % 8);
177 }
178
179 /**
180 * smk_netlabel_audit_set - fill a netlbl_audit struct
181 * @nap: structure to fill
182 */
smk_netlabel_audit_set(struct netlbl_audit * nap)183 static void smk_netlabel_audit_set(struct netlbl_audit *nap)
184 {
185 nap->loginuid = audit_get_loginuid(current);
186 nap->sessionid = audit_get_sessionid(current);
187 nap->prop.smack.skp = smk_of_current();
188 }
189
190 /*
191 * Value for parsing single label host rules
192 * "1.2.3.4 X"
193 */
194 #define SMK_NETLBLADDRMIN 9
195
196 /**
197 * smk_set_access - add a rule to the rule list or replace an old rule
198 * @srp: the rule to add or replace
199 * @rule_list: the list of rules
200 * @rule_lock: the rule list lock
201 *
202 * Looks through the current subject/object/access list for
203 * the subject/object pair and replaces the access that was
204 * there. If the pair isn't found add it with the specified
205 * access.
206 *
207 * Returns 0 if nothing goes wrong or -ENOMEM if it fails
208 * during the allocation of the new pair to add.
209 */
smk_set_access(struct smack_parsed_rule * srp,struct list_head * rule_list,struct mutex * rule_lock)210 static int smk_set_access(struct smack_parsed_rule *srp,
211 struct list_head *rule_list,
212 struct mutex *rule_lock)
213 {
214 struct smack_rule *sp;
215 int found = 0;
216 int rc = 0;
217
218 mutex_lock(rule_lock);
219
220 /*
221 * Because the object label is less likely to match
222 * than the subject label check it first
223 */
224 list_for_each_entry_rcu(sp, rule_list, list) {
225 if (sp->smk_object == srp->smk_object &&
226 sp->smk_subject == srp->smk_subject) {
227 found = 1;
228 sp->smk_access |= srp->smk_access1;
229 sp->smk_access &= ~srp->smk_access2;
230 break;
231 }
232 }
233
234 if (found == 0) {
235 sp = kmem_cache_zalloc(smack_rule_cache, GFP_KERNEL);
236 if (sp == NULL) {
237 rc = -ENOMEM;
238 goto out;
239 }
240
241 sp->smk_subject = srp->smk_subject;
242 sp->smk_object = srp->smk_object;
243 sp->smk_access = srp->smk_access1 & ~srp->smk_access2;
244
245 list_add_rcu(&sp->list, rule_list);
246 }
247
248 out:
249 mutex_unlock(rule_lock);
250 return rc;
251 }
252
253 /**
254 * smk_perm_from_str - parse smack accesses from a text string
255 * @string: a text string that contains a Smack accesses code
256 *
257 * Returns an integer with respective bits set for specified accesses.
258 */
smk_perm_from_str(const char * string)259 static int smk_perm_from_str(const char *string)
260 {
261 int perm = 0;
262 const char *cp;
263
264 for (cp = string; ; cp++)
265 switch (*cp) {
266 case '-':
267 break;
268 case 'r':
269 case 'R':
270 perm |= MAY_READ;
271 break;
272 case 'w':
273 case 'W':
274 perm |= MAY_WRITE;
275 break;
276 case 'x':
277 case 'X':
278 perm |= MAY_EXEC;
279 break;
280 case 'a':
281 case 'A':
282 perm |= MAY_APPEND;
283 break;
284 case 't':
285 case 'T':
286 perm |= MAY_TRANSMUTE;
287 break;
288 case 'l':
289 case 'L':
290 perm |= MAY_LOCK;
291 break;
292 case 'b':
293 case 'B':
294 perm |= MAY_BRINGUP;
295 break;
296 default:
297 return perm;
298 }
299 }
300
301 /**
302 * smk_fill_rule - Fill Smack rule from strings
303 * @subject: subject label string
304 * @object: object label string
305 * @access1: access string
306 * @access2: string with permissions to be removed
307 * @rule: Smack rule
308 * @import: if non-zero, import labels
309 * @len: label length limit
310 *
311 * Returns 0 on success, appropriate error code on failure.
312 */
smk_fill_rule(const char * subject,const char * object,const char * access1,const char * access2,struct smack_parsed_rule * rule,int import,int len)313 static int smk_fill_rule(const char *subject, const char *object,
314 const char *access1, const char *access2,
315 struct smack_parsed_rule *rule, int import,
316 int len)
317 {
318 const char *cp;
319 struct smack_known *skp;
320
321 if (import) {
322 rule->smk_subject = smk_import_entry(subject, len);
323 if (IS_ERR(rule->smk_subject))
324 return PTR_ERR(rule->smk_subject);
325
326 rule->smk_object = smk_import_entry(object, len);
327 if (IS_ERR(rule->smk_object))
328 return PTR_ERR(rule->smk_object);
329 } else {
330 cp = smk_parse_smack(subject, len);
331 if (IS_ERR(cp))
332 return PTR_ERR(cp);
333 skp = smk_find_entry(cp);
334 kfree(cp);
335 if (skp == NULL)
336 return -ENOENT;
337 rule->smk_subject = skp;
338
339 cp = smk_parse_smack(object, len);
340 if (IS_ERR(cp))
341 return PTR_ERR(cp);
342 skp = smk_find_entry(cp);
343 kfree(cp);
344 if (skp == NULL)
345 return -ENOENT;
346 rule->smk_object = skp;
347 }
348
349 rule->smk_access1 = smk_perm_from_str(access1);
350 if (access2)
351 rule->smk_access2 = smk_perm_from_str(access2);
352 else
353 rule->smk_access2 = ~rule->smk_access1;
354
355 return 0;
356 }
357
358 /**
359 * smk_parse_rule - parse Smack rule from load string
360 * @data: string to be parsed whose size is SMK_LOADLEN
361 * @rule: Smack rule
362 * @import: if non-zero, import labels
363 *
364 * Returns 0 on success, -1 on errors.
365 */
smk_parse_rule(const char * data,struct smack_parsed_rule * rule,int import)366 static int smk_parse_rule(const char *data, struct smack_parsed_rule *rule,
367 int import)
368 {
369 int rc;
370
371 rc = smk_fill_rule(data, data + SMK_LABELLEN,
372 data + SMK_LABELLEN + SMK_LABELLEN, NULL, rule,
373 import, SMK_LABELLEN);
374 return rc;
375 }
376
377 /**
378 * smk_parse_long_rule - parse Smack rule from rule string
379 * @data: string to be parsed, null terminated
380 * @rule: Will be filled with Smack parsed rule
381 * @import: if non-zero, import labels
382 * @tokens: number of substrings expected in data
383 *
384 * Returns number of processed bytes on success, -ERRNO on failure.
385 */
smk_parse_long_rule(char * data,struct smack_parsed_rule * rule,int import,int tokens)386 static ssize_t smk_parse_long_rule(char *data, struct smack_parsed_rule *rule,
387 int import, int tokens)
388 {
389 ssize_t cnt = 0;
390 char *tok[4];
391 int rc;
392 int i;
393
394 /*
395 * Parsing the rule in-place, filling all white-spaces with '\0'
396 */
397 for (i = 0; i < tokens; ++i) {
398 while (isspace(data[cnt]))
399 data[cnt++] = '\0';
400
401 if (data[cnt] == '\0')
402 /* Unexpected end of data */
403 return -EINVAL;
404
405 tok[i] = data + cnt;
406
407 while (data[cnt] && !isspace(data[cnt]))
408 ++cnt;
409 }
410 while (isspace(data[cnt]))
411 data[cnt++] = '\0';
412
413 while (i < 4)
414 tok[i++] = NULL;
415
416 rc = smk_fill_rule(tok[0], tok[1], tok[2], tok[3], rule, import, 0);
417 return rc == 0 ? cnt : rc;
418 }
419
420 #define SMK_FIXED24_FMT 0 /* Fixed 24byte label format */
421 #define SMK_LONG_FMT 1 /* Variable long label format */
422 #define SMK_CHANGE_FMT 2 /* Rule modification format */
423 /**
424 * smk_write_rules_list - write() for any /smack rule file
425 * @file: file pointer, not actually used
426 * @buf: where to get the data from
427 * @count: bytes sent
428 * @ppos: where to start - must be 0
429 * @rule_list: the list of rules to write to
430 * @rule_lock: lock for the rule list
431 * @format: /smack/load or /smack/load2 or /smack/change-rule format.
432 *
433 * Get one smack access rule from above.
434 * The format for SMK_LONG_FMT is:
435 * "subject<whitespace>object<whitespace>access[<whitespace>...]"
436 * The format for SMK_FIXED24_FMT is exactly:
437 * "subject object rwxat"
438 * The format for SMK_CHANGE_FMT is:
439 * "subject<whitespace>object<whitespace>
440 * acc_enable<whitespace>acc_disable[<whitespace>...]"
441 */
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)442 static ssize_t smk_write_rules_list(struct file *file, const char __user *buf,
443 size_t count, loff_t *ppos,
444 struct list_head *rule_list,
445 struct mutex *rule_lock, int format)
446 {
447 struct smack_parsed_rule rule;
448 char *data;
449 int rc;
450 int trunc = 0;
451 int tokens;
452 ssize_t cnt = 0;
453
454 /*
455 * No partial writes.
456 * Enough data must be present.
457 */
458 if (*ppos != 0)
459 return -EINVAL;
460
461 if (format == SMK_FIXED24_FMT) {
462 /*
463 * Minor hack for backward compatibility
464 */
465 if (count < SMK_OLOADLEN || count > SMK_LOADLEN)
466 return -EINVAL;
467 } else {
468 if (count >= PAGE_SIZE) {
469 count = PAGE_SIZE - 1;
470 trunc = 1;
471 }
472 }
473
474 data = memdup_user_nul(buf, count);
475 if (IS_ERR(data))
476 return PTR_ERR(data);
477
478 /*
479 * In case of parsing only part of user buf,
480 * avoid having partial rule at the data buffer
481 */
482 if (trunc) {
483 while (count > 0 && (data[count - 1] != '\n'))
484 --count;
485 if (count == 0) {
486 rc = -EINVAL;
487 goto out;
488 }
489 }
490
491 data[count] = '\0';
492 tokens = (format == SMK_CHANGE_FMT ? 4 : 3);
493 while (cnt < count) {
494 if (format == SMK_FIXED24_FMT) {
495 rc = smk_parse_rule(data, &rule, 1);
496 if (rc < 0)
497 goto out;
498 cnt = count;
499 } else {
500 rc = smk_parse_long_rule(data + cnt, &rule, 1, tokens);
501 if (rc < 0)
502 goto out;
503 if (rc == 0) {
504 rc = -EINVAL;
505 goto out;
506 }
507 cnt += rc;
508 }
509
510 if (rule_list == NULL)
511 rc = smk_set_access(&rule, &rule.smk_subject->smk_rules,
512 &rule.smk_subject->smk_rules_lock);
513 else
514 rc = smk_set_access(&rule, rule_list, rule_lock);
515
516 if (rc)
517 goto out;
518 }
519
520 rc = cnt;
521 out:
522 kfree(data);
523 return rc;
524 }
525
526 /*
527 * Core logic for smackfs seq list operations.
528 */
529
smk_seq_start(struct seq_file * s,loff_t * pos,struct list_head * head)530 static void *smk_seq_start(struct seq_file *s, loff_t *pos,
531 struct list_head *head)
532 {
533 struct list_head *list;
534 int i = *pos;
535
536 rcu_read_lock();
537 for (list = rcu_dereference(list_next_rcu(head));
538 list != head;
539 list = rcu_dereference(list_next_rcu(list))) {
540 if (i-- == 0)
541 return list;
542 }
543
544 return NULL;
545 }
546
smk_seq_next(struct seq_file * s,void * v,loff_t * pos,struct list_head * head)547 static void *smk_seq_next(struct seq_file *s, void *v, loff_t *pos,
548 struct list_head *head)
549 {
550 struct list_head *list = v;
551
552 ++*pos;
553 list = rcu_dereference(list_next_rcu(list));
554
555 return (list == head) ? NULL : list;
556 }
557
smk_seq_stop(struct seq_file * s,void * v)558 static void smk_seq_stop(struct seq_file *s, void *v)
559 {
560 rcu_read_unlock();
561 }
562
smk_rule_show(struct seq_file * s,struct smack_rule * srp,int max)563 static void smk_rule_show(struct seq_file *s, struct smack_rule *srp, int max)
564 {
565 /*
566 * Don't show any rules with label names too long for
567 * interface file (/smack/load or /smack/load2)
568 * because you should expect to be able to write
569 * anything you read back.
570 */
571 if (strlen(srp->smk_subject->smk_known) >= max ||
572 strlen(srp->smk_object->smk_known) >= max)
573 return;
574
575 if (srp->smk_access == 0)
576 return;
577
578 seq_printf(s, "%s %s",
579 srp->smk_subject->smk_known,
580 srp->smk_object->smk_known);
581
582 seq_putc(s, ' ');
583
584 if (srp->smk_access & MAY_READ)
585 seq_putc(s, 'r');
586 if (srp->smk_access & MAY_WRITE)
587 seq_putc(s, 'w');
588 if (srp->smk_access & MAY_EXEC)
589 seq_putc(s, 'x');
590 if (srp->smk_access & MAY_APPEND)
591 seq_putc(s, 'a');
592 if (srp->smk_access & MAY_TRANSMUTE)
593 seq_putc(s, 't');
594 if (srp->smk_access & MAY_LOCK)
595 seq_putc(s, 'l');
596 if (srp->smk_access & MAY_BRINGUP)
597 seq_putc(s, 'b');
598
599 seq_putc(s, '\n');
600 }
601
602 /*
603 * Seq_file read operations for /smack/load
604 */
605
load2_seq_start(struct seq_file * s,loff_t * pos)606 static void *load2_seq_start(struct seq_file *s, loff_t *pos)
607 {
608 return smk_seq_start(s, pos, &smack_known_list);
609 }
610
load2_seq_next(struct seq_file * s,void * v,loff_t * pos)611 static void *load2_seq_next(struct seq_file *s, void *v, loff_t *pos)
612 {
613 return smk_seq_next(s, v, pos, &smack_known_list);
614 }
615
load_seq_show(struct seq_file * s,void * v)616 static int load_seq_show(struct seq_file *s, void *v)
617 {
618 struct list_head *list = v;
619 struct smack_rule *srp;
620 struct smack_known *skp =
621 list_entry_rcu(list, struct smack_known, list);
622
623 list_for_each_entry_rcu(srp, &skp->smk_rules, list)
624 smk_rule_show(s, srp, SMK_LABELLEN);
625
626 return 0;
627 }
628
629 static const struct seq_operations load_seq_ops = {
630 .start = load2_seq_start,
631 .next = load2_seq_next,
632 .show = load_seq_show,
633 .stop = smk_seq_stop,
634 };
635
636 /**
637 * smk_open_load - open() for /smack/load
638 * @inode: inode structure representing file
639 * @file: "load" file pointer
640 *
641 * For reading, use load_seq_* seq_file reading operations.
642 */
smk_open_load(struct inode * inode,struct file * file)643 static int smk_open_load(struct inode *inode, struct file *file)
644 {
645 return seq_open(file, &load_seq_ops);
646 }
647
648 /**
649 * smk_write_load - write() for /smack/load
650 * @file: file pointer, not actually used
651 * @buf: where to get the data from
652 * @count: bytes sent
653 * @ppos: where to start - must be 0
654 *
655 */
smk_write_load(struct file * file,const char __user * buf,size_t count,loff_t * ppos)656 static ssize_t smk_write_load(struct file *file, const char __user *buf,
657 size_t count, loff_t *ppos)
658 {
659 /*
660 * Must have privilege.
661 * No partial writes.
662 * Enough data must be present.
663 */
664 if (!smack_privileged(CAP_MAC_ADMIN))
665 return -EPERM;
666
667 return smk_write_rules_list(file, buf, count, ppos, NULL, NULL,
668 SMK_FIXED24_FMT);
669 }
670
671 static const struct file_operations smk_load_ops = {
672 .open = smk_open_load,
673 .read = seq_read,
674 .llseek = seq_lseek,
675 .write = smk_write_load,
676 .release = seq_release,
677 };
678
679 /**
680 * smk_cipso_doi - initialize the CIPSO domain
681 */
smk_cipso_doi(void)682 static void smk_cipso_doi(void)
683 {
684 int rc;
685 struct cipso_v4_doi *doip;
686 struct netlbl_audit nai;
687
688 smk_netlabel_audit_set(&nai);
689
690 rc = netlbl_cfg_map_del(NULL, PF_INET, NULL, NULL, &nai);
691 if (rc != 0)
692 printk(KERN_WARNING "%s:%d remove rc = %d\n",
693 __func__, __LINE__, rc);
694
695 doip = kmalloc(sizeof(struct cipso_v4_doi), GFP_KERNEL | __GFP_NOFAIL);
696 doip->map.std = NULL;
697 doip->doi = smk_cipso_doi_value;
698 doip->type = CIPSO_V4_MAP_PASS;
699 doip->tags[0] = CIPSO_V4_TAG_RBITMAP;
700 for (rc = 1; rc < CIPSO_V4_TAG_MAXCNT; rc++)
701 doip->tags[rc] = CIPSO_V4_TAG_INVALID;
702
703 rc = netlbl_cfg_cipsov4_add(doip, &nai);
704 if (rc != 0) {
705 printk(KERN_WARNING "%s:%d cipso add rc = %d\n",
706 __func__, __LINE__, rc);
707 kfree(doip);
708 return;
709 }
710 rc = netlbl_cfg_cipsov4_map_add(doip->doi, NULL, NULL, NULL, &nai);
711 if (rc != 0) {
712 printk(KERN_WARNING "%s:%d map add rc = %d\n",
713 __func__, __LINE__, rc);
714 netlbl_cfg_cipsov4_del(doip->doi, &nai);
715 return;
716 }
717 }
718
719 /**
720 * smk_unlbl_ambient - initialize the unlabeled domain
721 * @oldambient: previous domain string
722 */
smk_unlbl_ambient(char * oldambient)723 static void smk_unlbl_ambient(char *oldambient)
724 {
725 int rc;
726 struct netlbl_audit nai;
727
728 smk_netlabel_audit_set(&nai);
729
730 if (oldambient != NULL) {
731 rc = netlbl_cfg_map_del(oldambient, PF_INET, NULL, NULL, &nai);
732 if (rc != 0)
733 printk(KERN_WARNING "%s:%d remove rc = %d\n",
734 __func__, __LINE__, rc);
735 }
736 if (smack_net_ambient == NULL)
737 smack_net_ambient = &smack_known_floor;
738
739 rc = netlbl_cfg_unlbl_map_add(smack_net_ambient->smk_known, PF_INET,
740 NULL, NULL, &nai);
741 if (rc != 0)
742 printk(KERN_WARNING "%s:%d add rc = %d\n",
743 __func__, __LINE__, rc);
744 }
745
746 /*
747 * Seq_file read operations for /smack/cipso
748 */
749
cipso_seq_start(struct seq_file * s,loff_t * pos)750 static void *cipso_seq_start(struct seq_file *s, loff_t *pos)
751 {
752 return smk_seq_start(s, pos, &smack_known_list);
753 }
754
cipso_seq_next(struct seq_file * s,void * v,loff_t * pos)755 static void *cipso_seq_next(struct seq_file *s, void *v, loff_t *pos)
756 {
757 return smk_seq_next(s, v, pos, &smack_known_list);
758 }
759
760 /*
761 * Print cipso labels in format:
762 * label level[/cat[,cat]]
763 */
cipso_seq_show(struct seq_file * s,void * v)764 static int cipso_seq_show(struct seq_file *s, void *v)
765 {
766 struct list_head *list = v;
767 struct smack_known *skp =
768 list_entry_rcu(list, struct smack_known, list);
769 struct netlbl_lsm_catmap *cmp = skp->smk_netlabel.attr.mls.cat;
770 char sep = '/';
771 int i;
772
773 /*
774 * Don't show a label that could not have been set using
775 * /smack/cipso. This is in support of the notion that
776 * anything read from /smack/cipso ought to be writeable
777 * to /smack/cipso.
778 *
779 * /smack/cipso2 should be used instead.
780 */
781 if (strlen(skp->smk_known) >= SMK_LABELLEN)
782 return 0;
783
784 seq_printf(s, "%s %3d", skp->smk_known, skp->smk_netlabel.attr.mls.lvl);
785
786 for (i = netlbl_catmap_walk(cmp, 0); i >= 0;
787 i = netlbl_catmap_walk(cmp, i + 1)) {
788 seq_printf(s, "%c%d", sep, i);
789 sep = ',';
790 }
791
792 seq_putc(s, '\n');
793
794 return 0;
795 }
796
797 static const struct seq_operations cipso_seq_ops = {
798 .start = cipso_seq_start,
799 .next = cipso_seq_next,
800 .show = cipso_seq_show,
801 .stop = smk_seq_stop,
802 };
803
804 /**
805 * smk_open_cipso - open() for /smack/cipso
806 * @inode: inode structure representing file
807 * @file: "cipso" file pointer
808 *
809 * Connect our cipso_seq_* operations with /smack/cipso
810 * file_operations
811 */
smk_open_cipso(struct inode * inode,struct file * file)812 static int smk_open_cipso(struct inode *inode, struct file *file)
813 {
814 return seq_open(file, &cipso_seq_ops);
815 }
816
817 /**
818 * smk_set_cipso - do the work for write() for cipso and cipso2
819 * @file: file pointer, not actually used
820 * @buf: where to get the data from
821 * @count: bytes sent
822 * @ppos: where to start
823 * @format: /smack/cipso or /smack/cipso2
824 *
825 * Accepts only one cipso rule per write call.
826 * Returns number of bytes written or error code, as appropriate
827 */
smk_set_cipso(struct file * file,const char __user * buf,size_t count,loff_t * ppos,int format)828 static ssize_t smk_set_cipso(struct file *file, const char __user *buf,
829 size_t count, loff_t *ppos, int format)
830 {
831 struct netlbl_lsm_catmap *old_cat, *new_cat = NULL;
832 struct smack_known *skp;
833 struct netlbl_lsm_secattr ncats;
834 char mapcatset[SMK_CIPSOLEN];
835 int maplevel;
836 unsigned int cat;
837 int catlen;
838 ssize_t rc = -EINVAL;
839 char *data = NULL;
840 char *rule;
841 int ret;
842 int i;
843
844 /*
845 * Must have privilege.
846 * No partial writes.
847 * Enough data must be present.
848 */
849 if (!smack_privileged(CAP_MAC_ADMIN))
850 return -EPERM;
851 if (*ppos != 0)
852 return -EINVAL;
853 if (format == SMK_FIXED24_FMT &&
854 (count < SMK_CIPSOMIN || count > SMK_CIPSOMAX))
855 return -EINVAL;
856 if (count > PAGE_SIZE)
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 < 0 || 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 ncats.flags = 0;
919 if (catlen == 0) {
920 ncats.attr.mls.cat = NULL;
921 ncats.attr.mls.lvl = maplevel;
922 new_cat = netlbl_catmap_alloc(GFP_ATOMIC);
923 if (new_cat)
924 new_cat->next = ncats.attr.mls.cat;
925 ncats.attr.mls.cat = new_cat;
926 skp->smk_netlabel.flags &= ~(1U << 3);
927 rc = 0;
928 } else {
929 rc = smk_netlbl_mls(maplevel, mapcatset, &ncats, SMK_CIPSOLEN);
930 }
931 if (rc >= 0) {
932 old_cat = skp->smk_netlabel.attr.mls.cat;
933 rcu_assign_pointer(skp->smk_netlabel.attr.mls.cat, ncats.attr.mls.cat);
934 skp->smk_netlabel.attr.mls.lvl = ncats.attr.mls.lvl;
935 synchronize_rcu();
936 netlbl_catmap_free(old_cat);
937 rc = count;
938 /*
939 * This mapping may have been cached, so clear the cache.
940 */
941 netlbl_cache_invalidate();
942 }
943
944 out:
945 mutex_unlock(&smack_cipso_lock);
946 kfree(data);
947 return rc;
948 }
949
950 /**
951 * smk_write_cipso - write() for /smack/cipso
952 * @file: file pointer, not actually used
953 * @buf: where to get the data from
954 * @count: bytes sent
955 * @ppos: where to start
956 *
957 * Accepts only one cipso rule per write call.
958 * Returns number of bytes written or error code, as appropriate
959 */
smk_write_cipso(struct file * file,const char __user * buf,size_t count,loff_t * ppos)960 static ssize_t smk_write_cipso(struct file *file, const char __user *buf,
961 size_t count, loff_t *ppos)
962 {
963 return smk_set_cipso(file, buf, count, ppos, SMK_FIXED24_FMT);
964 }
965
966 static const struct file_operations smk_cipso_ops = {
967 .open = smk_open_cipso,
968 .read = seq_read,
969 .llseek = seq_lseek,
970 .write = smk_write_cipso,
971 .release = seq_release,
972 };
973
974 /*
975 * Seq_file read operations for /smack/cipso2
976 */
977
978 /*
979 * Print cipso labels in format:
980 * label level[/cat[,cat]]
981 */
cipso2_seq_show(struct seq_file * s,void * v)982 static int cipso2_seq_show(struct seq_file *s, void *v)
983 {
984 struct list_head *list = v;
985 struct smack_known *skp =
986 list_entry_rcu(list, struct smack_known, list);
987 struct netlbl_lsm_catmap *cmp = skp->smk_netlabel.attr.mls.cat;
988 char sep = '/';
989 int i;
990
991 seq_printf(s, "%s %3d", skp->smk_known, skp->smk_netlabel.attr.mls.lvl);
992
993 for (i = netlbl_catmap_walk(cmp, 0); i >= 0;
994 i = netlbl_catmap_walk(cmp, i + 1)) {
995 seq_printf(s, "%c%d", sep, i);
996 sep = ',';
997 }
998
999 seq_putc(s, '\n');
1000
1001 return 0;
1002 }
1003
1004 static const struct seq_operations cipso2_seq_ops = {
1005 .start = cipso_seq_start,
1006 .next = cipso_seq_next,
1007 .show = cipso2_seq_show,
1008 .stop = smk_seq_stop,
1009 };
1010
1011 /**
1012 * smk_open_cipso2 - open() for /smack/cipso2
1013 * @inode: inode structure representing file
1014 * @file: "cipso2" file pointer
1015 *
1016 * Connect our cipso_seq_* operations with /smack/cipso2
1017 * file_operations
1018 */
smk_open_cipso2(struct inode * inode,struct file * file)1019 static int smk_open_cipso2(struct inode *inode, struct file *file)
1020 {
1021 return seq_open(file, &cipso2_seq_ops);
1022 }
1023
1024 /**
1025 * smk_write_cipso2 - write() for /smack/cipso2
1026 * @file: file pointer, not actually used
1027 * @buf: where to get the data from
1028 * @count: bytes sent
1029 * @ppos: where to start
1030 *
1031 * Accepts only one cipso rule per write call.
1032 * Returns number of bytes written or error code, as appropriate
1033 */
smk_write_cipso2(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1034 static ssize_t smk_write_cipso2(struct file *file, const char __user *buf,
1035 size_t count, loff_t *ppos)
1036 {
1037 return smk_set_cipso(file, buf, count, ppos, SMK_LONG_FMT);
1038 }
1039
1040 static const struct file_operations smk_cipso2_ops = {
1041 .open = smk_open_cipso2,
1042 .read = seq_read,
1043 .llseek = seq_lseek,
1044 .write = smk_write_cipso2,
1045 .release = seq_release,
1046 };
1047
1048 /*
1049 * Seq_file read operations for /smack/netlabel
1050 */
1051
net4addr_seq_start(struct seq_file * s,loff_t * pos)1052 static void *net4addr_seq_start(struct seq_file *s, loff_t *pos)
1053 {
1054 return smk_seq_start(s, pos, &smk_net4addr_list);
1055 }
1056
net4addr_seq_next(struct seq_file * s,void * v,loff_t * pos)1057 static void *net4addr_seq_next(struct seq_file *s, void *v, loff_t *pos)
1058 {
1059 return smk_seq_next(s, v, pos, &smk_net4addr_list);
1060 }
1061
1062 /*
1063 * Print host/label pairs
1064 */
net4addr_seq_show(struct seq_file * s,void * v)1065 static int net4addr_seq_show(struct seq_file *s, void *v)
1066 {
1067 struct list_head *list = v;
1068 struct smk_net4addr *skp =
1069 list_entry_rcu(list, struct smk_net4addr, list);
1070 char *kp = SMACK_CIPSO_OPTION;
1071
1072 if (skp->smk_label != NULL)
1073 kp = skp->smk_label->smk_known;
1074 seq_printf(s, "%pI4/%d %s\n", &skp->smk_host.s_addr,
1075 skp->smk_masks, kp);
1076
1077 return 0;
1078 }
1079
1080 static const struct seq_operations net4addr_seq_ops = {
1081 .start = net4addr_seq_start,
1082 .next = net4addr_seq_next,
1083 .show = net4addr_seq_show,
1084 .stop = smk_seq_stop,
1085 };
1086
1087 /**
1088 * smk_open_net4addr - open() for /smack/netlabel
1089 * @inode: inode structure representing file
1090 * @file: "netlabel" file pointer
1091 *
1092 * Connect our net4addr_seq_* operations with /smack/netlabel
1093 * file_operations
1094 */
smk_open_net4addr(struct inode * inode,struct file * file)1095 static int smk_open_net4addr(struct inode *inode, struct file *file)
1096 {
1097 return seq_open(file, &net4addr_seq_ops);
1098 }
1099
1100 /**
1101 * smk_net4addr_insert
1102 * @new : netlabel to insert
1103 *
1104 * This helper insert netlabel in the smack_net4addrs list
1105 * sorted by netmask length (longest to smallest)
1106 * locked by &smk_net4addr_lock in smk_write_net4addr
1107 *
1108 */
smk_net4addr_insert(struct smk_net4addr * new)1109 static void smk_net4addr_insert(struct smk_net4addr *new)
1110 {
1111 struct smk_net4addr *m;
1112 struct smk_net4addr *m_next;
1113
1114 if (list_empty(&smk_net4addr_list)) {
1115 list_add_rcu(&new->list, &smk_net4addr_list);
1116 return;
1117 }
1118
1119 m = list_entry_rcu(smk_net4addr_list.next,
1120 struct smk_net4addr, list);
1121
1122 /* the comparison '>' is a bit hacky, but works */
1123 if (new->smk_masks > m->smk_masks) {
1124 list_add_rcu(&new->list, &smk_net4addr_list);
1125 return;
1126 }
1127
1128 list_for_each_entry_rcu(m, &smk_net4addr_list, list) {
1129 if (list_is_last(&m->list, &smk_net4addr_list)) {
1130 list_add_rcu(&new->list, &m->list);
1131 return;
1132 }
1133 m_next = list_entry_rcu(m->list.next,
1134 struct smk_net4addr, list);
1135 if (new->smk_masks > m_next->smk_masks) {
1136 list_add_rcu(&new->list, &m->list);
1137 return;
1138 }
1139 }
1140 }
1141
1142
1143 /**
1144 * smk_write_net4addr - write() for /smack/netlabel
1145 * @file: file pointer, not actually used
1146 * @buf: where to get the data from
1147 * @count: bytes sent
1148 * @ppos: where to start
1149 *
1150 * Accepts only one net4addr per write call.
1151 * Returns number of bytes written or error code, as appropriate
1152 */
smk_write_net4addr(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1153 static ssize_t smk_write_net4addr(struct file *file, const char __user *buf,
1154 size_t count, loff_t *ppos)
1155 {
1156 struct smk_net4addr *snp;
1157 struct sockaddr_in newname;
1158 char *smack;
1159 struct smack_known *skp = NULL;
1160 char *data;
1161 char *host = (char *)&newname.sin_addr.s_addr;
1162 int rc;
1163 struct netlbl_audit audit_info;
1164 struct in_addr mask;
1165 unsigned int m;
1166 unsigned int masks;
1167 int found;
1168 u32 mask_bits = (1<<31);
1169 __be32 nsa;
1170 u32 temp_mask;
1171
1172 /*
1173 * Must have privilege.
1174 * No partial writes.
1175 * Enough data must be present.
1176 * "<addr/mask, as a.b.c.d/e><space><label>"
1177 * "<addr, as a.b.c.d><space><label>"
1178 */
1179 if (!smack_privileged(CAP_MAC_ADMIN))
1180 return -EPERM;
1181 if (*ppos != 0)
1182 return -EINVAL;
1183 if (count < SMK_NETLBLADDRMIN || count > PAGE_SIZE - 1)
1184 return -EINVAL;
1185
1186 data = memdup_user_nul(buf, count);
1187 if (IS_ERR(data))
1188 return PTR_ERR(data);
1189
1190 smack = kzalloc(count + 1, GFP_KERNEL);
1191 if (smack == NULL) {
1192 rc = -ENOMEM;
1193 goto free_data_out;
1194 }
1195
1196 rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd/%u %s",
1197 &host[0], &host[1], &host[2], &host[3], &masks, smack);
1198 if (rc != 6) {
1199 rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd %s",
1200 &host[0], &host[1], &host[2], &host[3], smack);
1201 if (rc != 5) {
1202 rc = -EINVAL;
1203 goto free_out;
1204 }
1205 masks = 32;
1206 }
1207 if (masks > BEBITS) {
1208 rc = -EINVAL;
1209 goto free_out;
1210 }
1211
1212 /*
1213 * If smack begins with '-', it is an option, don't import it
1214 */
1215 if (smack[0] != '-') {
1216 skp = smk_import_entry(smack, 0);
1217 if (IS_ERR(skp)) {
1218 rc = PTR_ERR(skp);
1219 goto free_out;
1220 }
1221 } else {
1222 /*
1223 * Only the -CIPSO option is supported for IPv4
1224 */
1225 if (strcmp(smack, SMACK_CIPSO_OPTION) != 0) {
1226 rc = -EINVAL;
1227 goto free_out;
1228 }
1229 }
1230
1231 for (m = masks, temp_mask = 0; m > 0; m--) {
1232 temp_mask |= mask_bits;
1233 mask_bits >>= 1;
1234 }
1235 mask.s_addr = cpu_to_be32(temp_mask);
1236
1237 newname.sin_addr.s_addr &= mask.s_addr;
1238 /*
1239 * Only allow one writer at a time. Writes should be
1240 * quite rare and small in any case.
1241 */
1242 mutex_lock(&smk_net4addr_lock);
1243
1244 nsa = newname.sin_addr.s_addr;
1245 /* try to find if the prefix is already in the list */
1246 found = 0;
1247 list_for_each_entry_rcu(snp, &smk_net4addr_list, list) {
1248 if (snp->smk_host.s_addr == nsa && snp->smk_masks == masks) {
1249 found = 1;
1250 break;
1251 }
1252 }
1253 smk_netlabel_audit_set(&audit_info);
1254
1255 if (found == 0) {
1256 snp = kzalloc(sizeof(*snp), GFP_KERNEL);
1257 if (snp == NULL)
1258 rc = -ENOMEM;
1259 else {
1260 rc = 0;
1261 snp->smk_host.s_addr = newname.sin_addr.s_addr;
1262 snp->smk_mask.s_addr = mask.s_addr;
1263 snp->smk_label = skp;
1264 snp->smk_masks = masks;
1265 smk_net4addr_insert(snp);
1266 }
1267 } else {
1268 /*
1269 * Delete the unlabeled entry, only if the previous label
1270 * wasn't the special CIPSO option
1271 */
1272 if (snp->smk_label != NULL)
1273 rc = netlbl_cfg_unlbl_static_del(&init_net, NULL,
1274 &snp->smk_host, &snp->smk_mask,
1275 PF_INET, &audit_info);
1276 else
1277 rc = 0;
1278 snp->smk_label = skp;
1279 }
1280
1281 /*
1282 * Now tell netlabel about the single label nature of
1283 * this host so that incoming packets get labeled.
1284 * but only if we didn't get the special CIPSO option
1285 */
1286 if (rc == 0 && skp != NULL)
1287 rc = netlbl_cfg_unlbl_static_add(&init_net, NULL,
1288 &snp->smk_host, &snp->smk_mask, PF_INET,
1289 snp->smk_label->smk_secid, &audit_info);
1290
1291 if (rc == 0)
1292 rc = count;
1293
1294 mutex_unlock(&smk_net4addr_lock);
1295
1296 free_out:
1297 kfree(smack);
1298 free_data_out:
1299 kfree(data);
1300
1301 return rc;
1302 }
1303
1304 static const struct file_operations smk_net4addr_ops = {
1305 .open = smk_open_net4addr,
1306 .read = seq_read,
1307 .llseek = seq_lseek,
1308 .write = smk_write_net4addr,
1309 .release = seq_release,
1310 };
1311
1312 #if IS_ENABLED(CONFIG_IPV6)
1313 /*
1314 * Seq_file read operations for /smack/netlabel6
1315 */
1316
net6addr_seq_start(struct seq_file * s,loff_t * pos)1317 static void *net6addr_seq_start(struct seq_file *s, loff_t *pos)
1318 {
1319 return smk_seq_start(s, pos, &smk_net6addr_list);
1320 }
1321
net6addr_seq_next(struct seq_file * s,void * v,loff_t * pos)1322 static void *net6addr_seq_next(struct seq_file *s, void *v, loff_t *pos)
1323 {
1324 return smk_seq_next(s, v, pos, &smk_net6addr_list);
1325 }
1326
1327 /*
1328 * Print host/label pairs
1329 */
net6addr_seq_show(struct seq_file * s,void * v)1330 static int net6addr_seq_show(struct seq_file *s, void *v)
1331 {
1332 struct list_head *list = v;
1333 struct smk_net6addr *skp =
1334 list_entry(list, struct smk_net6addr, list);
1335
1336 if (skp->smk_label != NULL)
1337 seq_printf(s, "%pI6/%d %s\n", &skp->smk_host, skp->smk_masks,
1338 skp->smk_label->smk_known);
1339
1340 return 0;
1341 }
1342
1343 static const struct seq_operations net6addr_seq_ops = {
1344 .start = net6addr_seq_start,
1345 .next = net6addr_seq_next,
1346 .show = net6addr_seq_show,
1347 .stop = smk_seq_stop,
1348 };
1349
1350 /**
1351 * smk_open_net6addr - open() for /smack/netlabel
1352 * @inode: inode structure representing file
1353 * @file: "netlabel" file pointer
1354 *
1355 * Connect our net6addr_seq_* operations with /smack/netlabel
1356 * file_operations
1357 */
smk_open_net6addr(struct inode * inode,struct file * file)1358 static int smk_open_net6addr(struct inode *inode, struct file *file)
1359 {
1360 return seq_open(file, &net6addr_seq_ops);
1361 }
1362
1363 /**
1364 * smk_net6addr_insert
1365 * @new : entry to insert
1366 *
1367 * This inserts an entry in the smack_net6addrs list
1368 * sorted by netmask length (longest to smallest)
1369 * locked by &smk_net6addr_lock in smk_write_net6addr
1370 *
1371 */
smk_net6addr_insert(struct smk_net6addr * new)1372 static void smk_net6addr_insert(struct smk_net6addr *new)
1373 {
1374 struct smk_net6addr *m_next;
1375 struct smk_net6addr *m;
1376
1377 if (list_empty(&smk_net6addr_list)) {
1378 list_add_rcu(&new->list, &smk_net6addr_list);
1379 return;
1380 }
1381
1382 m = list_entry_rcu(smk_net6addr_list.next,
1383 struct smk_net6addr, list);
1384
1385 if (new->smk_masks > m->smk_masks) {
1386 list_add_rcu(&new->list, &smk_net6addr_list);
1387 return;
1388 }
1389
1390 list_for_each_entry_rcu(m, &smk_net6addr_list, list) {
1391 if (list_is_last(&m->list, &smk_net6addr_list)) {
1392 list_add_rcu(&new->list, &m->list);
1393 return;
1394 }
1395 m_next = list_entry_rcu(m->list.next,
1396 struct smk_net6addr, list);
1397 if (new->smk_masks > m_next->smk_masks) {
1398 list_add_rcu(&new->list, &m->list);
1399 return;
1400 }
1401 }
1402 }
1403
1404
1405 /**
1406 * smk_write_net6addr - write() for /smack/netlabel
1407 * @file: file pointer, not actually used
1408 * @buf: where to get the data from
1409 * @count: bytes sent
1410 * @ppos: where to start
1411 *
1412 * Accepts only one net6addr per write call.
1413 * Returns number of bytes written or error code, as appropriate
1414 */
smk_write_net6addr(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1415 static ssize_t smk_write_net6addr(struct file *file, const char __user *buf,
1416 size_t count, loff_t *ppos)
1417 {
1418 struct smk_net6addr *snp;
1419 struct in6_addr newname;
1420 struct in6_addr fullmask;
1421 struct smack_known *skp = NULL;
1422 char *smack;
1423 char *data;
1424 int rc = 0;
1425 int found = 0;
1426 int i;
1427 unsigned int scanned[8];
1428 unsigned int m;
1429 unsigned int mask = 128;
1430
1431 /*
1432 * Must have privilege.
1433 * No partial writes.
1434 * Enough data must be present.
1435 * "<addr/mask, as a:b:c:d:e:f:g:h/e><space><label>"
1436 * "<addr, as a:b:c:d:e:f:g:h><space><label>"
1437 */
1438 if (!smack_privileged(CAP_MAC_ADMIN))
1439 return -EPERM;
1440 if (*ppos != 0)
1441 return -EINVAL;
1442 if (count < SMK_NETLBLADDRMIN || count > PAGE_SIZE - 1)
1443 return -EINVAL;
1444
1445 data = memdup_user_nul(buf, count);
1446 if (IS_ERR(data))
1447 return PTR_ERR(data);
1448
1449 smack = kzalloc(count + 1, GFP_KERNEL);
1450 if (smack == NULL) {
1451 rc = -ENOMEM;
1452 goto free_data_out;
1453 }
1454
1455 i = sscanf(data, "%x:%x:%x:%x:%x:%x:%x:%x/%u %s",
1456 &scanned[0], &scanned[1], &scanned[2], &scanned[3],
1457 &scanned[4], &scanned[5], &scanned[6], &scanned[7],
1458 &mask, smack);
1459 if (i != 10) {
1460 i = sscanf(data, "%x:%x:%x:%x:%x:%x:%x:%x %s",
1461 &scanned[0], &scanned[1], &scanned[2],
1462 &scanned[3], &scanned[4], &scanned[5],
1463 &scanned[6], &scanned[7], smack);
1464 if (i != 9) {
1465 rc = -EINVAL;
1466 goto free_out;
1467 }
1468 }
1469 if (mask > 128) {
1470 rc = -EINVAL;
1471 goto free_out;
1472 }
1473 for (i = 0; i < 8; i++) {
1474 if (scanned[i] > 0xffff) {
1475 rc = -EINVAL;
1476 goto free_out;
1477 }
1478 newname.s6_addr16[i] = htons(scanned[i]);
1479 }
1480
1481 /*
1482 * If smack begins with '-', it is an option, don't import it
1483 */
1484 if (smack[0] != '-') {
1485 skp = smk_import_entry(smack, 0);
1486 if (IS_ERR(skp)) {
1487 rc = PTR_ERR(skp);
1488 goto free_out;
1489 }
1490 } else {
1491 /*
1492 * Only -DELETE is supported for IPv6
1493 */
1494 if (strcmp(smack, SMACK_DELETE_OPTION) != 0) {
1495 rc = -EINVAL;
1496 goto free_out;
1497 }
1498 }
1499
1500 for (i = 0, m = mask; i < 8; i++) {
1501 if (m >= 16) {
1502 fullmask.s6_addr16[i] = 0xffff;
1503 m -= 16;
1504 } else if (m > 0) {
1505 fullmask.s6_addr16[i] = (1 << m) - 1;
1506 m = 0;
1507 } else
1508 fullmask.s6_addr16[i] = 0;
1509 newname.s6_addr16[i] &= fullmask.s6_addr16[i];
1510 }
1511
1512 /*
1513 * Only allow one writer at a time. Writes should be
1514 * quite rare and small in any case.
1515 */
1516 mutex_lock(&smk_net6addr_lock);
1517 /*
1518 * Try to find the prefix in the list
1519 */
1520 list_for_each_entry_rcu(snp, &smk_net6addr_list, list) {
1521 if (mask != snp->smk_masks)
1522 continue;
1523 for (found = 1, i = 0; i < 8; i++) {
1524 if (newname.s6_addr16[i] !=
1525 snp->smk_host.s6_addr16[i]) {
1526 found = 0;
1527 break;
1528 }
1529 }
1530 if (found == 1)
1531 break;
1532 }
1533 if (found == 0) {
1534 snp = kzalloc(sizeof(*snp), GFP_KERNEL);
1535 if (snp == NULL)
1536 rc = -ENOMEM;
1537 else {
1538 snp->smk_host = newname;
1539 snp->smk_mask = fullmask;
1540 snp->smk_masks = mask;
1541 snp->smk_label = skp;
1542 smk_net6addr_insert(snp);
1543 }
1544 } else {
1545 snp->smk_label = skp;
1546 }
1547
1548 if (rc == 0)
1549 rc = count;
1550
1551 mutex_unlock(&smk_net6addr_lock);
1552
1553 free_out:
1554 kfree(smack);
1555 free_data_out:
1556 kfree(data);
1557
1558 return rc;
1559 }
1560
1561 static const struct file_operations smk_net6addr_ops = {
1562 .open = smk_open_net6addr,
1563 .read = seq_read,
1564 .llseek = seq_lseek,
1565 .write = smk_write_net6addr,
1566 .release = seq_release,
1567 };
1568 #endif /* CONFIG_IPV6 */
1569
1570 /**
1571 * smk_read_doi - read() for /smack/doi
1572 * @filp: file pointer, not actually used
1573 * @buf: where to put the result
1574 * @count: maximum to send along
1575 * @ppos: where to start
1576 *
1577 * Returns number of bytes read or error code, as appropriate
1578 */
smk_read_doi(struct file * filp,char __user * buf,size_t count,loff_t * ppos)1579 static ssize_t smk_read_doi(struct file *filp, char __user *buf,
1580 size_t count, loff_t *ppos)
1581 {
1582 char temp[80];
1583 ssize_t rc;
1584
1585 if (*ppos != 0)
1586 return 0;
1587
1588 sprintf(temp, "%d", smk_cipso_doi_value);
1589 rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
1590
1591 return rc;
1592 }
1593
1594 /**
1595 * smk_write_doi - write() for /smack/doi
1596 * @file: file pointer, not actually used
1597 * @buf: where to get the data from
1598 * @count: bytes sent
1599 * @ppos: where to start
1600 *
1601 * Returns number of bytes written or error code, as appropriate
1602 */
smk_write_doi(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1603 static ssize_t smk_write_doi(struct file *file, const char __user *buf,
1604 size_t count, loff_t *ppos)
1605 {
1606 char temp[80];
1607 int i;
1608
1609 if (!smack_privileged(CAP_MAC_ADMIN))
1610 return -EPERM;
1611
1612 if (count >= sizeof(temp) || count == 0)
1613 return -EINVAL;
1614
1615 if (copy_from_user(temp, buf, count) != 0)
1616 return -EFAULT;
1617
1618 temp[count] = '\0';
1619
1620 if (sscanf(temp, "%d", &i) != 1)
1621 return -EINVAL;
1622
1623 smk_cipso_doi_value = i;
1624
1625 smk_cipso_doi();
1626
1627 return count;
1628 }
1629
1630 static const struct file_operations smk_doi_ops = {
1631 .read = smk_read_doi,
1632 .write = smk_write_doi,
1633 .llseek = default_llseek,
1634 };
1635
1636 /**
1637 * smk_read_direct - read() for /smack/direct
1638 * @filp: file pointer, not actually used
1639 * @buf: where to put the result
1640 * @count: maximum to send along
1641 * @ppos: where to start
1642 *
1643 * Returns number of bytes read or error code, as appropriate
1644 */
smk_read_direct(struct file * filp,char __user * buf,size_t count,loff_t * ppos)1645 static ssize_t smk_read_direct(struct file *filp, char __user *buf,
1646 size_t count, loff_t *ppos)
1647 {
1648 char temp[80];
1649 ssize_t rc;
1650
1651 if (*ppos != 0)
1652 return 0;
1653
1654 sprintf(temp, "%d", smack_cipso_direct);
1655 rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
1656
1657 return rc;
1658 }
1659
1660 /**
1661 * smk_write_direct - write() for /smack/direct
1662 * @file: file pointer, not actually used
1663 * @buf: where to get the data from
1664 * @count: bytes sent
1665 * @ppos: where to start
1666 *
1667 * Returns number of bytes written or error code, as appropriate
1668 */
smk_write_direct(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1669 static ssize_t smk_write_direct(struct file *file, const char __user *buf,
1670 size_t count, loff_t *ppos)
1671 {
1672 struct smack_known *skp;
1673 char temp[80];
1674 int i;
1675
1676 if (!smack_privileged(CAP_MAC_ADMIN))
1677 return -EPERM;
1678
1679 if (count >= sizeof(temp) || count == 0)
1680 return -EINVAL;
1681
1682 if (copy_from_user(temp, buf, count) != 0)
1683 return -EFAULT;
1684
1685 temp[count] = '\0';
1686
1687 if (sscanf(temp, "%d", &i) != 1)
1688 return -EINVAL;
1689
1690 /*
1691 * Don't do anything if the value hasn't actually changed.
1692 * If it is changing reset the level on entries that were
1693 * set up to be direct when they were created.
1694 */
1695 if (smack_cipso_direct != i) {
1696 mutex_lock(&smack_known_lock);
1697 list_for_each_entry_rcu(skp, &smack_known_list, list)
1698 if (skp->smk_netlabel.attr.mls.lvl ==
1699 smack_cipso_direct)
1700 skp->smk_netlabel.attr.mls.lvl = i;
1701 smack_cipso_direct = i;
1702 mutex_unlock(&smack_known_lock);
1703 }
1704
1705 return count;
1706 }
1707
1708 static const struct file_operations smk_direct_ops = {
1709 .read = smk_read_direct,
1710 .write = smk_write_direct,
1711 .llseek = default_llseek,
1712 };
1713
1714 /**
1715 * smk_read_mapped - read() for /smack/mapped
1716 * @filp: file pointer, not actually used
1717 * @buf: where to put the result
1718 * @count: maximum to send along
1719 * @ppos: where to start
1720 *
1721 * Returns number of bytes read or error code, as appropriate
1722 */
smk_read_mapped(struct file * filp,char __user * buf,size_t count,loff_t * ppos)1723 static ssize_t smk_read_mapped(struct file *filp, char __user *buf,
1724 size_t count, loff_t *ppos)
1725 {
1726 char temp[80];
1727 ssize_t rc;
1728
1729 if (*ppos != 0)
1730 return 0;
1731
1732 sprintf(temp, "%d", smack_cipso_mapped);
1733 rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
1734
1735 return rc;
1736 }
1737
1738 /**
1739 * smk_write_mapped - write() for /smack/mapped
1740 * @file: file pointer, not actually used
1741 * @buf: where to get the data from
1742 * @count: bytes sent
1743 * @ppos: where to start
1744 *
1745 * Returns number of bytes written or error code, as appropriate
1746 */
smk_write_mapped(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1747 static ssize_t smk_write_mapped(struct file *file, const char __user *buf,
1748 size_t count, loff_t *ppos)
1749 {
1750 struct smack_known *skp;
1751 char temp[80];
1752 int i;
1753
1754 if (!smack_privileged(CAP_MAC_ADMIN))
1755 return -EPERM;
1756
1757 if (count >= sizeof(temp) || count == 0)
1758 return -EINVAL;
1759
1760 if (copy_from_user(temp, buf, count) != 0)
1761 return -EFAULT;
1762
1763 temp[count] = '\0';
1764
1765 if (sscanf(temp, "%d", &i) != 1)
1766 return -EINVAL;
1767
1768 /*
1769 * Don't do anything if the value hasn't actually changed.
1770 * If it is changing reset the level on entries that were
1771 * set up to be mapped when they were created.
1772 */
1773 if (smack_cipso_mapped != i) {
1774 mutex_lock(&smack_known_lock);
1775 list_for_each_entry_rcu(skp, &smack_known_list, list)
1776 if (skp->smk_netlabel.attr.mls.lvl ==
1777 smack_cipso_mapped)
1778 skp->smk_netlabel.attr.mls.lvl = i;
1779 smack_cipso_mapped = i;
1780 mutex_unlock(&smack_known_lock);
1781 }
1782
1783 return count;
1784 }
1785
1786 static const struct file_operations smk_mapped_ops = {
1787 .read = smk_read_mapped,
1788 .write = smk_write_mapped,
1789 .llseek = default_llseek,
1790 };
1791
1792 /**
1793 * smk_read_ambient - read() for /smack/ambient
1794 * @filp: file pointer, not actually used
1795 * @buf: where to put the result
1796 * @cn: maximum to send along
1797 * @ppos: where to start
1798 *
1799 * Returns number of bytes read or error code, as appropriate
1800 */
smk_read_ambient(struct file * filp,char __user * buf,size_t cn,loff_t * ppos)1801 static ssize_t smk_read_ambient(struct file *filp, char __user *buf,
1802 size_t cn, loff_t *ppos)
1803 {
1804 ssize_t rc;
1805 int asize;
1806
1807 if (*ppos != 0)
1808 return 0;
1809 /*
1810 * Being careful to avoid a problem in the case where
1811 * smack_net_ambient gets changed in midstream.
1812 */
1813 mutex_lock(&smack_ambient_lock);
1814
1815 asize = strlen(smack_net_ambient->smk_known) + 1;
1816
1817 if (cn >= asize)
1818 rc = simple_read_from_buffer(buf, cn, ppos,
1819 smack_net_ambient->smk_known,
1820 asize);
1821 else
1822 rc = -EINVAL;
1823
1824 mutex_unlock(&smack_ambient_lock);
1825
1826 return rc;
1827 }
1828
1829 /**
1830 * smk_write_ambient - write() for /smack/ambient
1831 * @file: file pointer, not actually used
1832 * @buf: where to get the data from
1833 * @count: bytes sent
1834 * @ppos: where to start
1835 *
1836 * Returns number of bytes written or error code, as appropriate
1837 */
smk_write_ambient(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1838 static ssize_t smk_write_ambient(struct file *file, const char __user *buf,
1839 size_t count, loff_t *ppos)
1840 {
1841 struct smack_known *skp;
1842 char *oldambient;
1843 char *data;
1844 int rc = count;
1845
1846 if (!smack_privileged(CAP_MAC_ADMIN))
1847 return -EPERM;
1848
1849 /* Enough data must be present */
1850 if (count == 0 || count > PAGE_SIZE)
1851 return -EINVAL;
1852
1853 data = memdup_user_nul(buf, count);
1854 if (IS_ERR(data))
1855 return PTR_ERR(data);
1856
1857 skp = smk_import_entry(data, count);
1858 if (IS_ERR(skp)) {
1859 rc = PTR_ERR(skp);
1860 goto out;
1861 }
1862
1863 mutex_lock(&smack_ambient_lock);
1864
1865 oldambient = smack_net_ambient->smk_known;
1866 smack_net_ambient = skp;
1867 smk_unlbl_ambient(oldambient);
1868
1869 mutex_unlock(&smack_ambient_lock);
1870
1871 out:
1872 kfree(data);
1873 return rc;
1874 }
1875
1876 static const struct file_operations smk_ambient_ops = {
1877 .read = smk_read_ambient,
1878 .write = smk_write_ambient,
1879 .llseek = default_llseek,
1880 };
1881
1882 /*
1883 * Seq_file operations for /smack/onlycap
1884 */
onlycap_seq_start(struct seq_file * s,loff_t * pos)1885 static void *onlycap_seq_start(struct seq_file *s, loff_t *pos)
1886 {
1887 return smk_seq_start(s, pos, &smack_onlycap_list);
1888 }
1889
onlycap_seq_next(struct seq_file * s,void * v,loff_t * pos)1890 static void *onlycap_seq_next(struct seq_file *s, void *v, loff_t *pos)
1891 {
1892 return smk_seq_next(s, v, pos, &smack_onlycap_list);
1893 }
1894
onlycap_seq_show(struct seq_file * s,void * v)1895 static int onlycap_seq_show(struct seq_file *s, void *v)
1896 {
1897 struct list_head *list = v;
1898 struct smack_known_list_elem *sklep =
1899 list_entry_rcu(list, struct smack_known_list_elem, list);
1900
1901 seq_puts(s, sklep->smk_label->smk_known);
1902 seq_putc(s, ' ');
1903
1904 return 0;
1905 }
1906
1907 static const struct seq_operations onlycap_seq_ops = {
1908 .start = onlycap_seq_start,
1909 .next = onlycap_seq_next,
1910 .show = onlycap_seq_show,
1911 .stop = smk_seq_stop,
1912 };
1913
smk_open_onlycap(struct inode * inode,struct file * file)1914 static int smk_open_onlycap(struct inode *inode, struct file *file)
1915 {
1916 return seq_open(file, &onlycap_seq_ops);
1917 }
1918
1919 /**
1920 * smk_list_swap_rcu - swap public list with a private one in RCU-safe way
1921 * The caller must hold appropriate mutex to prevent concurrent modifications
1922 * to the public list.
1923 * Private list is assumed to be not accessible to other threads yet.
1924 *
1925 * @public: public list
1926 * @private: private list
1927 */
smk_list_swap_rcu(struct list_head * public,struct list_head * private)1928 static void smk_list_swap_rcu(struct list_head *public,
1929 struct list_head *private)
1930 {
1931 struct list_head *first, *last;
1932
1933 if (list_empty(public)) {
1934 list_splice_init_rcu(private, public, synchronize_rcu);
1935 } else {
1936 /* Remember public list before replacing it */
1937 first = public->next;
1938 last = public->prev;
1939
1940 /* Publish private list in place of public in RCU-safe way */
1941 private->prev->next = public;
1942 private->next->prev = public;
1943 rcu_assign_pointer(public->next, private->next);
1944 public->prev = private->prev;
1945
1946 synchronize_rcu();
1947
1948 /* When all readers are done with the old public list,
1949 * attach it in place of private */
1950 private->next = first;
1951 private->prev = last;
1952 first->prev = private;
1953 last->next = private;
1954 }
1955 }
1956
1957 /**
1958 * smk_parse_label_list - parse list of Smack labels, separated by spaces
1959 *
1960 * @data: the string to parse
1961 * @list: destination list
1962 *
1963 * Returns zero on success or error code, as appropriate
1964 */
smk_parse_label_list(char * data,struct list_head * list)1965 static int smk_parse_label_list(char *data, struct list_head *list)
1966 {
1967 char *tok;
1968 struct smack_known *skp;
1969 struct smack_known_list_elem *sklep;
1970
1971 while ((tok = strsep(&data, " ")) != NULL) {
1972 if (!*tok)
1973 continue;
1974
1975 skp = smk_import_entry(tok, 0);
1976 if (IS_ERR(skp))
1977 return PTR_ERR(skp);
1978
1979 sklep = kzalloc(sizeof(*sklep), GFP_KERNEL);
1980 if (sklep == NULL)
1981 return -ENOMEM;
1982
1983 sklep->smk_label = skp;
1984 list_add(&sklep->list, list);
1985 }
1986
1987 return 0;
1988 }
1989
1990 /**
1991 * smk_destroy_label_list - destroy a list of smack_known_list_elem
1992 * @list: header pointer of the list to destroy
1993 */
smk_destroy_label_list(struct list_head * list)1994 void smk_destroy_label_list(struct list_head *list)
1995 {
1996 struct smack_known_list_elem *sklep;
1997 struct smack_known_list_elem *sklep2;
1998
1999 list_for_each_entry_safe(sklep, sklep2, list, list)
2000 kfree(sklep);
2001
2002 INIT_LIST_HEAD(list);
2003 }
2004
2005 /**
2006 * smk_write_onlycap - write() for smackfs/onlycap
2007 * @file: file pointer, not actually used
2008 * @buf: where to get the data from
2009 * @count: bytes sent
2010 * @ppos: where to start
2011 *
2012 * Returns number of bytes written or error code, as appropriate
2013 */
smk_write_onlycap(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2014 static ssize_t smk_write_onlycap(struct file *file, const char __user *buf,
2015 size_t count, loff_t *ppos)
2016 {
2017 char *data;
2018 LIST_HEAD(list_tmp);
2019 int rc;
2020
2021 if (!smack_privileged(CAP_MAC_ADMIN))
2022 return -EPERM;
2023
2024 if (count > PAGE_SIZE)
2025 return -EINVAL;
2026
2027 data = memdup_user_nul(buf, count);
2028 if (IS_ERR(data))
2029 return PTR_ERR(data);
2030
2031 rc = smk_parse_label_list(data, &list_tmp);
2032 kfree(data);
2033
2034 /*
2035 * Clear the smack_onlycap on invalid label errors. This means
2036 * that we can pass a null string to unset the onlycap value.
2037 *
2038 * Importing will also reject a label beginning with '-',
2039 * so "-usecapabilities" will also work.
2040 *
2041 * But do so only on invalid label, not on system errors.
2042 * The invalid label must be first to count as clearing attempt.
2043 */
2044 if (!rc || (rc == -EINVAL && list_empty(&list_tmp))) {
2045 mutex_lock(&smack_onlycap_lock);
2046 smk_list_swap_rcu(&smack_onlycap_list, &list_tmp);
2047 mutex_unlock(&smack_onlycap_lock);
2048 rc = count;
2049 }
2050
2051 smk_destroy_label_list(&list_tmp);
2052
2053 return rc;
2054 }
2055
2056 static const struct file_operations smk_onlycap_ops = {
2057 .open = smk_open_onlycap,
2058 .read = seq_read,
2059 .write = smk_write_onlycap,
2060 .llseek = seq_lseek,
2061 .release = seq_release,
2062 };
2063
2064 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
2065 /**
2066 * smk_read_unconfined - read() for smackfs/unconfined
2067 * @filp: file pointer, not actually used
2068 * @buf: where to put the result
2069 * @cn: maximum to send along
2070 * @ppos: where to start
2071 *
2072 * Returns number of bytes read or error code, as appropriate
2073 */
smk_read_unconfined(struct file * filp,char __user * buf,size_t cn,loff_t * ppos)2074 static ssize_t smk_read_unconfined(struct file *filp, char __user *buf,
2075 size_t cn, loff_t *ppos)
2076 {
2077 char *smack = "";
2078 ssize_t rc = -EINVAL;
2079 int asize;
2080
2081 if (*ppos != 0)
2082 return 0;
2083
2084 if (smack_unconfined != NULL)
2085 smack = smack_unconfined->smk_known;
2086
2087 asize = strlen(smack) + 1;
2088
2089 if (cn >= asize)
2090 rc = simple_read_from_buffer(buf, cn, ppos, smack, asize);
2091
2092 return rc;
2093 }
2094
2095 /**
2096 * smk_write_unconfined - write() for smackfs/unconfined
2097 * @file: file pointer, not actually used
2098 * @buf: where to get the data from
2099 * @count: bytes sent
2100 * @ppos: where to start
2101 *
2102 * Returns number of bytes written or error code, as appropriate
2103 */
smk_write_unconfined(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2104 static ssize_t smk_write_unconfined(struct file *file, const char __user *buf,
2105 size_t count, loff_t *ppos)
2106 {
2107 char *data;
2108 struct smack_known *skp;
2109 int rc = count;
2110
2111 if (!smack_privileged(CAP_MAC_ADMIN))
2112 return -EPERM;
2113
2114 if (count > PAGE_SIZE)
2115 return -EINVAL;
2116
2117 data = memdup_user_nul(buf, count);
2118 if (IS_ERR(data))
2119 return PTR_ERR(data);
2120
2121 /*
2122 * Clear the smack_unconfined on invalid label errors. This means
2123 * that we can pass a null string to unset the unconfined value.
2124 *
2125 * Importing will also reject a label beginning with '-',
2126 * so "-confine" will also work.
2127 *
2128 * But do so only on invalid label, not on system errors.
2129 */
2130 skp = smk_import_entry(data, count);
2131 if (PTR_ERR(skp) == -EINVAL)
2132 skp = NULL;
2133 else if (IS_ERR(skp)) {
2134 rc = PTR_ERR(skp);
2135 goto freeout;
2136 }
2137
2138 smack_unconfined = skp;
2139
2140 freeout:
2141 kfree(data);
2142 return rc;
2143 }
2144
2145 static const struct file_operations smk_unconfined_ops = {
2146 .read = smk_read_unconfined,
2147 .write = smk_write_unconfined,
2148 .llseek = default_llseek,
2149 };
2150 #endif /* CONFIG_SECURITY_SMACK_BRINGUP */
2151
2152 /**
2153 * smk_read_logging - read() for /smack/logging
2154 * @filp: file pointer, not actually used
2155 * @buf: where to put the result
2156 * @count: maximum to send along
2157 * @ppos: where to start
2158 *
2159 * Returns number of bytes read or error code, as appropriate
2160 */
smk_read_logging(struct file * filp,char __user * buf,size_t count,loff_t * ppos)2161 static ssize_t smk_read_logging(struct file *filp, char __user *buf,
2162 size_t count, loff_t *ppos)
2163 {
2164 char temp[32];
2165 ssize_t rc;
2166
2167 if (*ppos != 0)
2168 return 0;
2169
2170 sprintf(temp, "%d\n", log_policy);
2171 rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
2172 return rc;
2173 }
2174
2175 /**
2176 * smk_write_logging - write() for /smack/logging
2177 * @file: file pointer, not actually used
2178 * @buf: where to get the data from
2179 * @count: bytes sent
2180 * @ppos: where to start
2181 *
2182 * Returns number of bytes written or error code, as appropriate
2183 */
smk_write_logging(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2184 static ssize_t smk_write_logging(struct file *file, const char __user *buf,
2185 size_t count, loff_t *ppos)
2186 {
2187 char temp[32];
2188 int i;
2189
2190 if (!smack_privileged(CAP_MAC_ADMIN))
2191 return -EPERM;
2192
2193 if (count >= sizeof(temp) || count == 0)
2194 return -EINVAL;
2195
2196 if (copy_from_user(temp, buf, count) != 0)
2197 return -EFAULT;
2198
2199 temp[count] = '\0';
2200
2201 if (sscanf(temp, "%d", &i) != 1)
2202 return -EINVAL;
2203 if (i < 0 || i > 3)
2204 return -EINVAL;
2205 log_policy = i;
2206 return count;
2207 }
2208
2209
2210
2211 static const struct file_operations smk_logging_ops = {
2212 .read = smk_read_logging,
2213 .write = smk_write_logging,
2214 .llseek = default_llseek,
2215 };
2216
2217 /*
2218 * Seq_file read operations for /smack/load-self
2219 */
2220
load_self_seq_start(struct seq_file * s,loff_t * pos)2221 static void *load_self_seq_start(struct seq_file *s, loff_t *pos)
2222 {
2223 struct task_smack *tsp = smack_cred(current_cred());
2224
2225 return smk_seq_start(s, pos, &tsp->smk_rules);
2226 }
2227
load_self_seq_next(struct seq_file * s,void * v,loff_t * pos)2228 static void *load_self_seq_next(struct seq_file *s, void *v, loff_t *pos)
2229 {
2230 struct task_smack *tsp = smack_cred(current_cred());
2231
2232 return smk_seq_next(s, v, pos, &tsp->smk_rules);
2233 }
2234
load_self_seq_show(struct seq_file * s,void * v)2235 static int load_self_seq_show(struct seq_file *s, void *v)
2236 {
2237 struct list_head *list = v;
2238 struct smack_rule *srp =
2239 list_entry_rcu(list, struct smack_rule, list);
2240
2241 smk_rule_show(s, srp, SMK_LABELLEN);
2242
2243 return 0;
2244 }
2245
2246 static const struct seq_operations load_self_seq_ops = {
2247 .start = load_self_seq_start,
2248 .next = load_self_seq_next,
2249 .show = load_self_seq_show,
2250 .stop = smk_seq_stop,
2251 };
2252
2253
2254 /**
2255 * smk_open_load_self - open() for /smack/load-self2
2256 * @inode: inode structure representing file
2257 * @file: "load" file pointer
2258 *
2259 * For reading, use load_seq_* seq_file reading operations.
2260 */
smk_open_load_self(struct inode * inode,struct file * file)2261 static int smk_open_load_self(struct inode *inode, struct file *file)
2262 {
2263 return seq_open(file, &load_self_seq_ops);
2264 }
2265
2266 /**
2267 * smk_write_load_self - write() for /smack/load-self
2268 * @file: file pointer, not actually used
2269 * @buf: where to get the data from
2270 * @count: bytes sent
2271 * @ppos: where to start - must be 0
2272 *
2273 */
smk_write_load_self(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2274 static ssize_t smk_write_load_self(struct file *file, const char __user *buf,
2275 size_t count, loff_t *ppos)
2276 {
2277 struct task_smack *tsp = smack_cred(current_cred());
2278
2279 return smk_write_rules_list(file, buf, count, ppos, &tsp->smk_rules,
2280 &tsp->smk_rules_lock, SMK_FIXED24_FMT);
2281 }
2282
2283 static const struct file_operations smk_load_self_ops = {
2284 .open = smk_open_load_self,
2285 .read = seq_read,
2286 .llseek = seq_lseek,
2287 .write = smk_write_load_self,
2288 .release = seq_release,
2289 };
2290
2291 /**
2292 * smk_user_access - handle access check transaction
2293 * @file: file pointer
2294 * @buf: data from user space
2295 * @count: bytes sent
2296 * @ppos: where to start - must be 0
2297 * @format: /smack/load or /smack/load2 or /smack/change-rule format.
2298 */
smk_user_access(struct file * file,const char __user * buf,size_t count,loff_t * ppos,int format)2299 static ssize_t smk_user_access(struct file *file, const char __user *buf,
2300 size_t count, loff_t *ppos, int format)
2301 {
2302 struct smack_parsed_rule rule;
2303 char *data;
2304 int res;
2305
2306 data = simple_transaction_get(file, buf, count);
2307 if (IS_ERR(data))
2308 return PTR_ERR(data);
2309
2310 if (format == SMK_FIXED24_FMT) {
2311 if (count < SMK_LOADLEN)
2312 return -EINVAL;
2313 res = smk_parse_rule(data, &rule, 0);
2314 } else {
2315 /*
2316 * simple_transaction_get() returns null-terminated data
2317 */
2318 res = smk_parse_long_rule(data, &rule, 0, 3);
2319 }
2320
2321 if (res >= 0)
2322 res = smk_access(rule.smk_subject, rule.smk_object,
2323 rule.smk_access1, NULL);
2324 else if (res != -ENOENT)
2325 return res;
2326
2327 /*
2328 * smk_access() can return a value > 0 in the "bringup" case.
2329 */
2330 data[0] = res >= 0 ? '1' : '0';
2331 data[1] = '\0';
2332
2333 simple_transaction_set(file, 2);
2334
2335 if (format == SMK_FIXED24_FMT)
2336 return SMK_LOADLEN;
2337 return count;
2338 }
2339
2340 /**
2341 * smk_write_access - handle access check transaction
2342 * @file: file pointer
2343 * @buf: data from user space
2344 * @count: bytes sent
2345 * @ppos: where to start - must be 0
2346 */
smk_write_access(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2347 static ssize_t smk_write_access(struct file *file, const char __user *buf,
2348 size_t count, loff_t *ppos)
2349 {
2350 return smk_user_access(file, buf, count, ppos, SMK_FIXED24_FMT);
2351 }
2352
2353 static const struct file_operations smk_access_ops = {
2354 .write = smk_write_access,
2355 .read = simple_transaction_read,
2356 .release = simple_transaction_release,
2357 .llseek = generic_file_llseek,
2358 };
2359
2360
2361 /*
2362 * Seq_file read operations for /smack/load2
2363 */
2364
load2_seq_show(struct seq_file * s,void * v)2365 static int load2_seq_show(struct seq_file *s, void *v)
2366 {
2367 struct list_head *list = v;
2368 struct smack_rule *srp;
2369 struct smack_known *skp =
2370 list_entry_rcu(list, struct smack_known, list);
2371
2372 list_for_each_entry_rcu(srp, &skp->smk_rules, list)
2373 smk_rule_show(s, srp, SMK_LONGLABEL);
2374
2375 return 0;
2376 }
2377
2378 static const struct seq_operations load2_seq_ops = {
2379 .start = load2_seq_start,
2380 .next = load2_seq_next,
2381 .show = load2_seq_show,
2382 .stop = smk_seq_stop,
2383 };
2384
2385 /**
2386 * smk_open_load2 - open() for /smack/load2
2387 * @inode: inode structure representing file
2388 * @file: "load2" file pointer
2389 *
2390 * For reading, use load2_seq_* seq_file reading operations.
2391 */
smk_open_load2(struct inode * inode,struct file * file)2392 static int smk_open_load2(struct inode *inode, struct file *file)
2393 {
2394 return seq_open(file, &load2_seq_ops);
2395 }
2396
2397 /**
2398 * smk_write_load2 - write() for /smack/load2
2399 * @file: file pointer, not actually used
2400 * @buf: where to get the data from
2401 * @count: bytes sent
2402 * @ppos: where to start - must be 0
2403 *
2404 */
smk_write_load2(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2405 static ssize_t smk_write_load2(struct file *file, const char __user *buf,
2406 size_t count, loff_t *ppos)
2407 {
2408 /*
2409 * Must have privilege.
2410 */
2411 if (!smack_privileged(CAP_MAC_ADMIN))
2412 return -EPERM;
2413
2414 return smk_write_rules_list(file, buf, count, ppos, NULL, NULL,
2415 SMK_LONG_FMT);
2416 }
2417
2418 static const struct file_operations smk_load2_ops = {
2419 .open = smk_open_load2,
2420 .read = seq_read,
2421 .llseek = seq_lseek,
2422 .write = smk_write_load2,
2423 .release = seq_release,
2424 };
2425
2426 /*
2427 * Seq_file read operations for /smack/load-self2
2428 */
2429
load_self2_seq_start(struct seq_file * s,loff_t * pos)2430 static void *load_self2_seq_start(struct seq_file *s, loff_t *pos)
2431 {
2432 struct task_smack *tsp = smack_cred(current_cred());
2433
2434 return smk_seq_start(s, pos, &tsp->smk_rules);
2435 }
2436
load_self2_seq_next(struct seq_file * s,void * v,loff_t * pos)2437 static void *load_self2_seq_next(struct seq_file *s, void *v, loff_t *pos)
2438 {
2439 struct task_smack *tsp = smack_cred(current_cred());
2440
2441 return smk_seq_next(s, v, pos, &tsp->smk_rules);
2442 }
2443
load_self2_seq_show(struct seq_file * s,void * v)2444 static int load_self2_seq_show(struct seq_file *s, void *v)
2445 {
2446 struct list_head *list = v;
2447 struct smack_rule *srp =
2448 list_entry_rcu(list, struct smack_rule, list);
2449
2450 smk_rule_show(s, srp, SMK_LONGLABEL);
2451
2452 return 0;
2453 }
2454
2455 static const struct seq_operations load_self2_seq_ops = {
2456 .start = load_self2_seq_start,
2457 .next = load_self2_seq_next,
2458 .show = load_self2_seq_show,
2459 .stop = smk_seq_stop,
2460 };
2461
2462 /**
2463 * smk_open_load_self2 - open() for /smack/load-self2
2464 * @inode: inode structure representing file
2465 * @file: "load" file pointer
2466 *
2467 * For reading, use load_seq_* seq_file reading operations.
2468 */
smk_open_load_self2(struct inode * inode,struct file * file)2469 static int smk_open_load_self2(struct inode *inode, struct file *file)
2470 {
2471 return seq_open(file, &load_self2_seq_ops);
2472 }
2473
2474 /**
2475 * smk_write_load_self2 - write() for /smack/load-self2
2476 * @file: file pointer, not actually used
2477 * @buf: where to get the data from
2478 * @count: bytes sent
2479 * @ppos: where to start - must be 0
2480 *
2481 */
smk_write_load_self2(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2482 static ssize_t smk_write_load_self2(struct file *file, const char __user *buf,
2483 size_t count, loff_t *ppos)
2484 {
2485 struct task_smack *tsp = smack_cred(current_cred());
2486
2487 return smk_write_rules_list(file, buf, count, ppos, &tsp->smk_rules,
2488 &tsp->smk_rules_lock, SMK_LONG_FMT);
2489 }
2490
2491 static const struct file_operations smk_load_self2_ops = {
2492 .open = smk_open_load_self2,
2493 .read = seq_read,
2494 .llseek = seq_lseek,
2495 .write = smk_write_load_self2,
2496 .release = seq_release,
2497 };
2498
2499 /**
2500 * smk_write_access2 - handle access check transaction
2501 * @file: file pointer
2502 * @buf: data from user space
2503 * @count: bytes sent
2504 * @ppos: where to start - must be 0
2505 */
smk_write_access2(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2506 static ssize_t smk_write_access2(struct file *file, const char __user *buf,
2507 size_t count, loff_t *ppos)
2508 {
2509 return smk_user_access(file, buf, count, ppos, SMK_LONG_FMT);
2510 }
2511
2512 static const struct file_operations smk_access2_ops = {
2513 .write = smk_write_access2,
2514 .read = simple_transaction_read,
2515 .release = simple_transaction_release,
2516 .llseek = generic_file_llseek,
2517 };
2518
2519 /**
2520 * smk_write_revoke_subj - write() for /smack/revoke-subject
2521 * @file: file pointer
2522 * @buf: data from user space
2523 * @count: bytes sent
2524 * @ppos: where to start - must be 0
2525 */
smk_write_revoke_subj(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2526 static ssize_t smk_write_revoke_subj(struct file *file, const char __user *buf,
2527 size_t count, loff_t *ppos)
2528 {
2529 char *data;
2530 const char *cp;
2531 struct smack_known *skp;
2532 struct smack_rule *sp;
2533 struct list_head *rule_list;
2534 struct mutex *rule_lock;
2535 int rc = count;
2536
2537 if (*ppos != 0)
2538 return -EINVAL;
2539
2540 if (!smack_privileged(CAP_MAC_ADMIN))
2541 return -EPERM;
2542
2543 if (count == 0 || count > SMK_LONGLABEL)
2544 return -EINVAL;
2545
2546 data = memdup_user(buf, count);
2547 if (IS_ERR(data))
2548 return PTR_ERR(data);
2549
2550 cp = smk_parse_smack(data, count);
2551 if (IS_ERR(cp)) {
2552 rc = PTR_ERR(cp);
2553 goto out_data;
2554 }
2555
2556 skp = smk_find_entry(cp);
2557 if (skp == NULL)
2558 goto out_cp;
2559
2560 rule_list = &skp->smk_rules;
2561 rule_lock = &skp->smk_rules_lock;
2562
2563 mutex_lock(rule_lock);
2564
2565 list_for_each_entry_rcu(sp, rule_list, list)
2566 sp->smk_access = 0;
2567
2568 mutex_unlock(rule_lock);
2569
2570 out_cp:
2571 kfree(cp);
2572 out_data:
2573 kfree(data);
2574
2575 return rc;
2576 }
2577
2578 static const struct file_operations smk_revoke_subj_ops = {
2579 .write = smk_write_revoke_subj,
2580 .read = simple_transaction_read,
2581 .release = simple_transaction_release,
2582 .llseek = generic_file_llseek,
2583 };
2584
2585 /**
2586 * smk_init_sysfs - initialize /sys/fs/smackfs
2587 *
2588 */
smk_init_sysfs(void)2589 static int smk_init_sysfs(void)
2590 {
2591 return sysfs_create_mount_point(fs_kobj, "smackfs");
2592 }
2593
2594 /**
2595 * smk_write_change_rule - write() for /smack/change-rule
2596 * @file: file pointer
2597 * @buf: data from user space
2598 * @count: bytes sent
2599 * @ppos: where to start - must be 0
2600 */
smk_write_change_rule(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2601 static ssize_t smk_write_change_rule(struct file *file, const char __user *buf,
2602 size_t count, loff_t *ppos)
2603 {
2604 /*
2605 * Must have privilege.
2606 */
2607 if (!smack_privileged(CAP_MAC_ADMIN))
2608 return -EPERM;
2609
2610 return smk_write_rules_list(file, buf, count, ppos, NULL, NULL,
2611 SMK_CHANGE_FMT);
2612 }
2613
2614 static const struct file_operations smk_change_rule_ops = {
2615 .write = smk_write_change_rule,
2616 .read = simple_transaction_read,
2617 .release = simple_transaction_release,
2618 .llseek = generic_file_llseek,
2619 };
2620
2621 /**
2622 * smk_read_syslog - read() for smackfs/syslog
2623 * @filp: file pointer, not actually used
2624 * @buf: where to put the result
2625 * @cn: maximum to send along
2626 * @ppos: where to start
2627 *
2628 * Returns number of bytes read or error code, as appropriate
2629 */
smk_read_syslog(struct file * filp,char __user * buf,size_t cn,loff_t * ppos)2630 static ssize_t smk_read_syslog(struct file *filp, char __user *buf,
2631 size_t cn, loff_t *ppos)
2632 {
2633 struct smack_known *skp;
2634 ssize_t rc = -EINVAL;
2635 int asize;
2636
2637 if (*ppos != 0)
2638 return 0;
2639
2640 if (smack_syslog_label == NULL)
2641 skp = &smack_known_star;
2642 else
2643 skp = smack_syslog_label;
2644
2645 asize = strlen(skp->smk_known) + 1;
2646
2647 if (cn >= asize)
2648 rc = simple_read_from_buffer(buf, cn, ppos, skp->smk_known,
2649 asize);
2650
2651 return rc;
2652 }
2653
2654 /**
2655 * smk_write_syslog - write() for smackfs/syslog
2656 * @file: file pointer, not actually used
2657 * @buf: where to get the data from
2658 * @count: bytes sent
2659 * @ppos: where to start
2660 *
2661 * Returns number of bytes written or error code, as appropriate
2662 */
smk_write_syslog(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2663 static ssize_t smk_write_syslog(struct file *file, const char __user *buf,
2664 size_t count, loff_t *ppos)
2665 {
2666 char *data;
2667 struct smack_known *skp;
2668 int rc = count;
2669
2670 if (!smack_privileged(CAP_MAC_ADMIN))
2671 return -EPERM;
2672
2673 /* Enough data must be present */
2674 if (count == 0 || count > PAGE_SIZE)
2675 return -EINVAL;
2676
2677 data = memdup_user_nul(buf, count);
2678 if (IS_ERR(data))
2679 return PTR_ERR(data);
2680
2681 skp = smk_import_entry(data, count);
2682 if (IS_ERR(skp))
2683 rc = PTR_ERR(skp);
2684 else
2685 smack_syslog_label = skp;
2686
2687 kfree(data);
2688 return rc;
2689 }
2690
2691 static const struct file_operations smk_syslog_ops = {
2692 .read = smk_read_syslog,
2693 .write = smk_write_syslog,
2694 .llseek = default_llseek,
2695 };
2696
2697 /*
2698 * Seq_file read operations for /smack/relabel-self
2699 */
2700
relabel_self_seq_start(struct seq_file * s,loff_t * pos)2701 static void *relabel_self_seq_start(struct seq_file *s, loff_t *pos)
2702 {
2703 struct task_smack *tsp = smack_cred(current_cred());
2704
2705 return smk_seq_start(s, pos, &tsp->smk_relabel);
2706 }
2707
relabel_self_seq_next(struct seq_file * s,void * v,loff_t * pos)2708 static void *relabel_self_seq_next(struct seq_file *s, void *v, loff_t *pos)
2709 {
2710 struct task_smack *tsp = smack_cred(current_cred());
2711
2712 return smk_seq_next(s, v, pos, &tsp->smk_relabel);
2713 }
2714
relabel_self_seq_show(struct seq_file * s,void * v)2715 static int relabel_self_seq_show(struct seq_file *s, void *v)
2716 {
2717 struct list_head *list = v;
2718 struct smack_known_list_elem *sklep =
2719 list_entry(list, struct smack_known_list_elem, list);
2720
2721 seq_puts(s, sklep->smk_label->smk_known);
2722 seq_putc(s, ' ');
2723
2724 return 0;
2725 }
2726
2727 static const struct seq_operations relabel_self_seq_ops = {
2728 .start = relabel_self_seq_start,
2729 .next = relabel_self_seq_next,
2730 .show = relabel_self_seq_show,
2731 .stop = smk_seq_stop,
2732 };
2733
2734 /**
2735 * smk_open_relabel_self - open() for /smack/relabel-self
2736 * @inode: inode structure representing file
2737 * @file: "relabel-self" file pointer
2738 *
2739 * Connect our relabel_self_seq_* operations with /smack/relabel-self
2740 * file_operations
2741 */
smk_open_relabel_self(struct inode * inode,struct file * file)2742 static int smk_open_relabel_self(struct inode *inode, struct file *file)
2743 {
2744 return seq_open(file, &relabel_self_seq_ops);
2745 }
2746
2747 /**
2748 * smk_write_relabel_self - write() for /smack/relabel-self
2749 * @file: file pointer, not actually used
2750 * @buf: where to get the data from
2751 * @count: bytes sent
2752 * @ppos: where to start - must be 0
2753 *
2754 */
smk_write_relabel_self(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2755 static ssize_t smk_write_relabel_self(struct file *file, const char __user *buf,
2756 size_t count, loff_t *ppos)
2757 {
2758 char *data;
2759 int rc;
2760 LIST_HEAD(list_tmp);
2761
2762 /*
2763 * Must have privilege.
2764 */
2765 if (!smack_privileged(CAP_MAC_ADMIN))
2766 return -EPERM;
2767
2768 /*
2769 * No partial write.
2770 * Enough data must be present.
2771 */
2772 if (*ppos != 0)
2773 return -EINVAL;
2774 if (count == 0 || count > PAGE_SIZE)
2775 return -EINVAL;
2776
2777 data = memdup_user_nul(buf, count);
2778 if (IS_ERR(data))
2779 return PTR_ERR(data);
2780
2781 rc = smk_parse_label_list(data, &list_tmp);
2782 kfree(data);
2783
2784 if (!rc || (rc == -EINVAL && list_empty(&list_tmp))) {
2785 struct cred *new;
2786 struct task_smack *tsp;
2787
2788 new = prepare_creds();
2789 if (!new) {
2790 rc = -ENOMEM;
2791 goto out;
2792 }
2793 tsp = smack_cred(new);
2794 smk_destroy_label_list(&tsp->smk_relabel);
2795 list_splice(&list_tmp, &tsp->smk_relabel);
2796 commit_creds(new);
2797 return count;
2798 }
2799 out:
2800 smk_destroy_label_list(&list_tmp);
2801 return rc;
2802 }
2803
2804 static const struct file_operations smk_relabel_self_ops = {
2805 .open = smk_open_relabel_self,
2806 .read = seq_read,
2807 .llseek = seq_lseek,
2808 .write = smk_write_relabel_self,
2809 .release = seq_release,
2810 };
2811
2812 /**
2813 * smk_read_ptrace - read() for /smack/ptrace
2814 * @filp: file pointer, not actually used
2815 * @buf: where to put the result
2816 * @count: maximum to send along
2817 * @ppos: where to start
2818 *
2819 * Returns number of bytes read or error code, as appropriate
2820 */
smk_read_ptrace(struct file * filp,char __user * buf,size_t count,loff_t * ppos)2821 static ssize_t smk_read_ptrace(struct file *filp, char __user *buf,
2822 size_t count, loff_t *ppos)
2823 {
2824 char temp[32];
2825 ssize_t rc;
2826
2827 if (*ppos != 0)
2828 return 0;
2829
2830 sprintf(temp, "%d\n", smack_ptrace_rule);
2831 rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
2832 return rc;
2833 }
2834
2835 /**
2836 * smk_write_ptrace - write() for /smack/ptrace
2837 * @file: file pointer
2838 * @buf: data from user space
2839 * @count: bytes sent
2840 * @ppos: where to start - must be 0
2841 */
smk_write_ptrace(struct file * file,const char __user * buf,size_t count,loff_t * ppos)2842 static ssize_t smk_write_ptrace(struct file *file, const char __user *buf,
2843 size_t count, loff_t *ppos)
2844 {
2845 char temp[32];
2846 int i;
2847
2848 if (!smack_privileged(CAP_MAC_ADMIN))
2849 return -EPERM;
2850
2851 if (*ppos != 0 || count >= sizeof(temp) || count == 0)
2852 return -EINVAL;
2853
2854 if (copy_from_user(temp, buf, count) != 0)
2855 return -EFAULT;
2856
2857 temp[count] = '\0';
2858
2859 if (sscanf(temp, "%d", &i) != 1)
2860 return -EINVAL;
2861 if (i < SMACK_PTRACE_DEFAULT || i > SMACK_PTRACE_MAX)
2862 return -EINVAL;
2863 smack_ptrace_rule = i;
2864
2865 return count;
2866 }
2867
2868 static const struct file_operations smk_ptrace_ops = {
2869 .write = smk_write_ptrace,
2870 .read = smk_read_ptrace,
2871 .llseek = default_llseek,
2872 };
2873
2874 /**
2875 * smk_fill_super - fill the smackfs superblock
2876 * @sb: the empty superblock
2877 * @fc: unused
2878 *
2879 * Fill in the well known entries for the smack filesystem
2880 *
2881 * Returns 0 on success, an error code on failure
2882 */
smk_fill_super(struct super_block * sb,struct fs_context * fc)2883 static int smk_fill_super(struct super_block *sb, struct fs_context *fc)
2884 {
2885 int rc;
2886
2887 static const struct tree_descr smack_files[] = {
2888 [SMK_LOAD] = {
2889 "load", &smk_load_ops, S_IRUGO|S_IWUSR},
2890 [SMK_CIPSO] = {
2891 "cipso", &smk_cipso_ops, S_IRUGO|S_IWUSR},
2892 [SMK_DOI] = {
2893 "doi", &smk_doi_ops, S_IRUGO|S_IWUSR},
2894 [SMK_DIRECT] = {
2895 "direct", &smk_direct_ops, S_IRUGO|S_IWUSR},
2896 [SMK_AMBIENT] = {
2897 "ambient", &smk_ambient_ops, S_IRUGO|S_IWUSR},
2898 [SMK_NET4ADDR] = {
2899 "netlabel", &smk_net4addr_ops, S_IRUGO|S_IWUSR},
2900 [SMK_ONLYCAP] = {
2901 "onlycap", &smk_onlycap_ops, S_IRUGO|S_IWUSR},
2902 [SMK_LOGGING] = {
2903 "logging", &smk_logging_ops, S_IRUGO|S_IWUSR},
2904 [SMK_LOAD_SELF] = {
2905 "load-self", &smk_load_self_ops, S_IRUGO|S_IWUGO},
2906 [SMK_ACCESSES] = {
2907 "access", &smk_access_ops, S_IRUGO|S_IWUGO},
2908 [SMK_MAPPED] = {
2909 "mapped", &smk_mapped_ops, S_IRUGO|S_IWUSR},
2910 [SMK_LOAD2] = {
2911 "load2", &smk_load2_ops, S_IRUGO|S_IWUSR},
2912 [SMK_LOAD_SELF2] = {
2913 "load-self2", &smk_load_self2_ops, S_IRUGO|S_IWUGO},
2914 [SMK_ACCESS2] = {
2915 "access2", &smk_access2_ops, S_IRUGO|S_IWUGO},
2916 [SMK_CIPSO2] = {
2917 "cipso2", &smk_cipso2_ops, S_IRUGO|S_IWUSR},
2918 [SMK_REVOKE_SUBJ] = {
2919 "revoke-subject", &smk_revoke_subj_ops,
2920 S_IRUGO|S_IWUSR},
2921 [SMK_CHANGE_RULE] = {
2922 "change-rule", &smk_change_rule_ops, S_IRUGO|S_IWUSR},
2923 [SMK_SYSLOG] = {
2924 "syslog", &smk_syslog_ops, S_IRUGO|S_IWUSR},
2925 [SMK_PTRACE] = {
2926 "ptrace", &smk_ptrace_ops, S_IRUGO|S_IWUSR},
2927 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
2928 [SMK_UNCONFINED] = {
2929 "unconfined", &smk_unconfined_ops, S_IRUGO|S_IWUSR},
2930 #endif
2931 #if IS_ENABLED(CONFIG_IPV6)
2932 [SMK_NET6ADDR] = {
2933 "ipv6host", &smk_net6addr_ops, S_IRUGO|S_IWUSR},
2934 #endif /* CONFIG_IPV6 */
2935 [SMK_RELABEL_SELF] = {
2936 "relabel-self", &smk_relabel_self_ops,
2937 S_IRUGO|S_IWUGO},
2938 /* last one */
2939 {""}
2940 };
2941
2942 rc = simple_fill_super(sb, SMACK_MAGIC, smack_files);
2943 if (rc != 0) {
2944 printk(KERN_ERR "%s failed %d while creating inodes\n",
2945 __func__, rc);
2946 return rc;
2947 }
2948
2949 return 0;
2950 }
2951
2952 /**
2953 * smk_get_tree - get the smackfs superblock
2954 * @fc: The mount context, including any options
2955 *
2956 * Just passes everything along.
2957 *
2958 * Returns what the lower level code does.
2959 */
smk_get_tree(struct fs_context * fc)2960 static int smk_get_tree(struct fs_context *fc)
2961 {
2962 return get_tree_single(fc, smk_fill_super);
2963 }
2964
2965 static const struct fs_context_operations smk_context_ops = {
2966 .get_tree = smk_get_tree,
2967 };
2968
2969 /**
2970 * smk_init_fs_context - Initialise a filesystem context for smackfs
2971 * @fc: The blank mount context
2972 */
smk_init_fs_context(struct fs_context * fc)2973 static int smk_init_fs_context(struct fs_context *fc)
2974 {
2975 fc->ops = &smk_context_ops;
2976 return 0;
2977 }
2978
2979 static struct file_system_type smk_fs_type = {
2980 .name = "smackfs",
2981 .init_fs_context = smk_init_fs_context,
2982 .kill_sb = kill_litter_super,
2983 };
2984
2985 static struct vfsmount *smackfs_mount;
2986
2987 /**
2988 * init_smk_fs - get the smackfs superblock
2989 *
2990 * register the smackfs
2991 *
2992 * Do not register smackfs if Smack wasn't enabled
2993 * on boot. We can not put this method normally under the
2994 * smack_init() code path since the security subsystem get
2995 * initialized before the vfs caches.
2996 *
2997 * Returns true if we were not chosen on boot or if
2998 * we were chosen and filesystem registration succeeded.
2999 */
init_smk_fs(void)3000 static int __init init_smk_fs(void)
3001 {
3002 int err;
3003 int rc;
3004
3005 if (smack_enabled == 0)
3006 return 0;
3007
3008 err = smk_init_sysfs();
3009 if (err)
3010 printk(KERN_ERR "smackfs: sysfs mountpoint problem.\n");
3011
3012 err = register_filesystem(&smk_fs_type);
3013 if (!err) {
3014 smackfs_mount = kern_mount(&smk_fs_type);
3015 if (IS_ERR(smackfs_mount)) {
3016 printk(KERN_ERR "smackfs: could not mount!\n");
3017 err = PTR_ERR(smackfs_mount);
3018 smackfs_mount = NULL;
3019 }
3020 }
3021
3022 smk_cipso_doi();
3023 smk_unlbl_ambient(NULL);
3024
3025 rc = smack_populate_secattr(&smack_known_floor);
3026 if (err == 0 && rc < 0)
3027 err = rc;
3028 rc = smack_populate_secattr(&smack_known_hat);
3029 if (err == 0 && rc < 0)
3030 err = rc;
3031 rc = smack_populate_secattr(&smack_known_huh);
3032 if (err == 0 && rc < 0)
3033 err = rc;
3034 rc = smack_populate_secattr(&smack_known_star);
3035 if (err == 0 && rc < 0)
3036 err = rc;
3037 rc = smack_populate_secattr(&smack_known_web);
3038 if (err == 0 && rc < 0)
3039 err = rc;
3040
3041 return err;
3042 }
3043
3044 __initcall(init_smk_fs);
3045