CRED: Constify the kernel_cap_t arguments to the capset LSM hooks
[linux-2.6-block.git] / security / commoncap.c
CommitLineData
e338d263 1/* Common capabilities, needed by capability.o and root_plug.o
1da177e4
LT
2 *
3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License as published by
5 * the Free Software Foundation; either version 2 of the License, or
6 * (at your option) any later version.
7 *
8 */
9
c59ede7b 10#include <linux/capability.h>
3fc689e9 11#include <linux/audit.h>
1da177e4
LT
12#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/kernel.h>
15#include <linux/security.h>
16#include <linux/file.h>
17#include <linux/mm.h>
18#include <linux/mman.h>
19#include <linux/pagemap.h>
20#include <linux/swap.h>
1da177e4
LT
21#include <linux/skbuff.h>
22#include <linux/netlink.h>
23#include <linux/ptrace.h>
24#include <linux/xattr.h>
25#include <linux/hugetlb.h>
b5376771 26#include <linux/mount.h>
b460cbc5 27#include <linux/sched.h>
3898b1b4
AM
28#include <linux/prctl.h>
29#include <linux/securebits.h>
72c2d582 30
1da177e4
LT
31int cap_netlink_send(struct sock *sk, struct sk_buff *skb)
32{
33 NETLINK_CB(skb).eff_cap = current->cap_effective;
34 return 0;
35}
36
c7bdb545 37int cap_netlink_recv(struct sk_buff *skb, int cap)
1da177e4 38{
c7bdb545 39 if (!cap_raised(NETLINK_CB(skb).eff_cap, cap))
1da177e4
LT
40 return -EPERM;
41 return 0;
42}
43
44EXPORT_SYMBOL(cap_netlink_recv);
45
a6dbb1ef
AM
46/*
47 * NOTE WELL: cap_capable() cannot be used like the kernel's capable()
48 * function. That is, it has the reverse semantics: cap_capable()
49 * returns 0 when a task has a capability, but the kernel's capable()
50 * returns 1 for this case.
51 */
06112163 52int cap_capable(struct task_struct *tsk, int cap, int audit)
1da177e4
LT
53{
54 /* Derived from include/linux/sched.h:capable. */
55 if (cap_raised(tsk->cap_effective, cap))
56 return 0;
57 return -EPERM;
58}
59
60int cap_settime(struct timespec *ts, struct timezone *tz)
61{
62 if (!capable(CAP_SYS_TIME))
63 return -EPERM;
64 return 0;
65}
66
5cd9c58f 67int cap_ptrace_may_access(struct task_struct *child, unsigned int mode)
1da177e4
LT
68{
69 /* Derived from arch/i386/kernel/ptrace.c:sys_ptrace. */
5cd9c58f
DH
70 if (cap_issubset(child->cap_permitted, current->cap_permitted))
71 return 0;
72 if (capable(CAP_SYS_PTRACE))
73 return 0;
74 return -EPERM;
75}
76
77int cap_ptrace_traceme(struct task_struct *parent)
78{
79 /* Derived from arch/i386/kernel/ptrace.c:sys_ptrace. */
80 if (cap_issubset(current->cap_permitted, parent->cap_permitted))
81 return 0;
82 if (has_capability(parent, CAP_SYS_PTRACE))
83 return 0;
84 return -EPERM;
1da177e4
LT
85}
86
87int cap_capget (struct task_struct *target, kernel_cap_t *effective,
88 kernel_cap_t *inheritable, kernel_cap_t *permitted)
89{
90 /* Derived from kernel/capability.c:sys_capget. */
e338d263
AM
91 *effective = target->cap_effective;
92 *inheritable = target->cap_inheritable;
93 *permitted = target->cap_permitted;
1da177e4
LT
94 return 0;
95}
96
72c2d582
AM
97#ifdef CONFIG_SECURITY_FILE_CAPABILITIES
98
72c2d582
AM
99static inline int cap_inh_is_capped(void)
100{
101 /*
a6dbb1ef
AM
102 * Return 1 if changes to the inheritable set are limited
103 * to the old permitted set. That is, if the current task
104 * does *not* possess the CAP_SETPCAP capability.
72c2d582 105 */
06112163 106 return (cap_capable(current, CAP_SETPCAP, SECURITY_CAP_AUDIT) != 0);
72c2d582
AM
107}
108
1209726c
AM
109static inline int cap_limit_ptraced_target(void) { return 1; }
110
72c2d582
AM
111#else /* ie., ndef CONFIG_SECURITY_FILE_CAPABILITIES */
112
72c2d582 113static inline int cap_inh_is_capped(void) { return 1; }
1209726c
AM
114static inline int cap_limit_ptraced_target(void)
115{
116 return !capable(CAP_SETPCAP);
117}
72c2d582
AM
118
119#endif /* def CONFIG_SECURITY_FILE_CAPABILITIES */
120
15a2460e
DH
121int cap_capset_check(const kernel_cap_t *effective,
122 const kernel_cap_t *inheritable,
123 const kernel_cap_t *permitted)
1da177e4 124{
72c2d582
AM
125 if (cap_inh_is_capped()
126 && !cap_issubset(*inheritable,
1cdcbec1 127 cap_combine(current->cap_inheritable,
72c2d582
AM
128 current->cap_permitted))) {
129 /* incapable of using this inheritable set */
1da177e4
LT
130 return -EPERM;
131 }
3b7391de 132 if (!cap_issubset(*inheritable,
1cdcbec1 133 cap_combine(current->cap_inheritable,
3b7391de
SH
134 current->cap_bset))) {
135 /* no new pI capabilities outside bounding set */
136 return -EPERM;
137 }
1da177e4
LT
138
139 /* verify restrictions on target's new Permitted set */
140 if (!cap_issubset (*permitted,
1cdcbec1 141 cap_combine (current->cap_permitted,
1da177e4
LT
142 current->cap_permitted))) {
143 return -EPERM;
144 }
145
146 /* verify the _new_Effective_ is a subset of the _new_Permitted_ */
147 if (!cap_issubset (*effective, *permitted)) {
148 return -EPERM;
149 }
150
151 return 0;
152}
153
15a2460e
DH
154void cap_capset_set(const kernel_cap_t *effective,
155 const kernel_cap_t *inheritable,
156 const kernel_cap_t *permitted)
1da177e4 157{
1cdcbec1
DH
158 current->cap_effective = *effective;
159 current->cap_inheritable = *inheritable;
160 current->cap_permitted = *permitted;
1da177e4
LT
161}
162
b5376771
SH
163static inline void bprm_clear_caps(struct linux_binprm *bprm)
164{
5459c164 165 cap_clear(bprm->cap_post_exec_permitted);
b5376771
SH
166 bprm->cap_effective = false;
167}
168
169#ifdef CONFIG_SECURITY_FILE_CAPABILITIES
170
171int cap_inode_need_killpriv(struct dentry *dentry)
172{
173 struct inode *inode = dentry->d_inode;
174 int error;
175
176 if (!inode->i_op || !inode->i_op->getxattr)
177 return 0;
178
179 error = inode->i_op->getxattr(dentry, XATTR_NAME_CAPS, NULL, 0);
180 if (error <= 0)
181 return 0;
182 return 1;
183}
184
185int cap_inode_killpriv(struct dentry *dentry)
186{
187 struct inode *inode = dentry->d_inode;
188
189 if (!inode->i_op || !inode->i_op->removexattr)
190 return 0;
191
192 return inode->i_op->removexattr(dentry, XATTR_NAME_CAPS);
193}
194
c0b00441
EP
195static inline int bprm_caps_from_vfs_caps(struct cpu_vfs_cap_data *caps,
196 struct linux_binprm *bprm)
b5376771 197{
c0b00441
EP
198 unsigned i;
199 int ret = 0;
200
201 if (caps->magic_etc & VFS_CAP_FLAGS_EFFECTIVE)
202 bprm->cap_effective = true;
203 else
204 bprm->cap_effective = false;
205
206 CAP_FOR_EACH_U32(i) {
207 __u32 permitted = caps->permitted.cap[i];
208 __u32 inheritable = caps->inheritable.cap[i];
209
210 /*
211 * pP' = (X & fP) | (pI & fI)
212 */
213 bprm->cap_post_exec_permitted.cap[i] =
214 (current->cap_bset.cap[i] & permitted) |
215 (current->cap_inheritable.cap[i] & inheritable);
216
217 if (permitted & ~bprm->cap_post_exec_permitted.cap[i]) {
218 /*
219 * insufficient to execute correctly
220 */
221 ret = -EPERM;
222 }
223 }
224
225 /*
226 * For legacy apps, with no internal support for recognizing they
227 * do not have enough capabilities, we return an error if they are
228 * missing some "forced" (aka file-permitted) capabilities.
229 */
230 return bprm->cap_effective ? ret : 0;
231}
232
233int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps)
234{
235 struct inode *inode = dentry->d_inode;
b5376771 236 __u32 magic_etc;
e338d263 237 unsigned tocopy, i;
c0b00441
EP
238 int size;
239 struct vfs_cap_data caps;
240
241 memset(cpu_caps, 0, sizeof(struct cpu_vfs_cap_data));
242
243 if (!inode || !inode->i_op || !inode->i_op->getxattr)
244 return -ENODATA;
245
246 size = inode->i_op->getxattr((struct dentry *)dentry, XATTR_NAME_CAPS, &caps,
247 XATTR_CAPS_SZ);
248 if (size == -ENODATA || size == -EOPNOTSUPP) {
249 /* no data, that's ok */
250 return -ENODATA;
251 }
252 if (size < 0)
253 return size;
b5376771 254
e338d263 255 if (size < sizeof(magic_etc))
b5376771
SH
256 return -EINVAL;
257
c0b00441 258 cpu_caps->magic_etc = magic_etc = le32_to_cpu(caps.magic_etc);
b5376771
SH
259
260 switch ((magic_etc & VFS_CAP_REVISION_MASK)) {
e338d263
AM
261 case VFS_CAP_REVISION_1:
262 if (size != XATTR_CAPS_SZ_1)
263 return -EINVAL;
264 tocopy = VFS_CAP_U32_1;
265 break;
266 case VFS_CAP_REVISION_2:
267 if (size != XATTR_CAPS_SZ_2)
268 return -EINVAL;
269 tocopy = VFS_CAP_U32_2;
270 break;
b5376771
SH
271 default:
272 return -EINVAL;
273 }
e338d263 274
5459c164 275 CAP_FOR_EACH_U32(i) {
c0b00441
EP
276 if (i >= tocopy)
277 break;
278 cpu_caps->permitted.cap[i] = le32_to_cpu(caps.data[i].permitted);
279 cpu_caps->inheritable.cap[i] = le32_to_cpu(caps.data[i].inheritable);
e338d263 280 }
c0b00441 281 return 0;
b5376771
SH
282}
283
284/* Locate any VFS capabilities: */
285static int get_file_caps(struct linux_binprm *bprm)
286{
287 struct dentry *dentry;
288 int rc = 0;
c0b00441 289 struct cpu_vfs_cap_data vcaps;
b5376771 290
3318a386
SH
291 bprm_clear_caps(bprm);
292
1f29fae2
SH
293 if (!file_caps_enabled)
294 return 0;
295
3318a386 296 if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID)
b5376771 297 return 0;
b5376771
SH
298
299 dentry = dget(bprm->file->f_dentry);
b5376771 300
c0b00441
EP
301 rc = get_vfs_caps_from_disk(dentry, &vcaps);
302 if (rc < 0) {
303 if (rc == -EINVAL)
304 printk(KERN_NOTICE "%s: get_vfs_caps_from_disk returned %d for %s\n",
305 __func__, rc, bprm->filename);
306 else if (rc == -ENODATA)
307 rc = 0;
b5376771
SH
308 goto out;
309 }
b5376771 310
c0b00441 311 rc = bprm_caps_from_vfs_caps(&vcaps, bprm);
b5376771
SH
312
313out:
314 dput(dentry);
315 if (rc)
316 bprm_clear_caps(bprm);
317
318 return rc;
319}
320
321#else
322int cap_inode_need_killpriv(struct dentry *dentry)
323{
324 return 0;
325}
326
327int cap_inode_killpriv(struct dentry *dentry)
328{
329 return 0;
330}
331
332static inline int get_file_caps(struct linux_binprm *bprm)
333{
334 bprm_clear_caps(bprm);
335 return 0;
336}
337#endif
338
1da177e4
LT
339int cap_bprm_set_security (struct linux_binprm *bprm)
340{
b5376771 341 int ret;
1da177e4 342
b5376771 343 ret = get_file_caps(bprm);
1da177e4 344
5459c164
AM
345 if (!issecure(SECURE_NOROOT)) {
346 /*
347 * To support inheritance of root-permissions and suid-root
348 * executables under compatibility mode, we override the
349 * capability sets for the file.
350 *
351 * If only the real uid is 0, we do not set the effective
352 * bit.
353 */
b103c598 354 if (bprm->e_uid == 0 || current_uid() == 0) {
5459c164
AM
355 /* pP' = (cap_bset & ~0) | (pI & ~0) */
356 bprm->cap_post_exec_permitted = cap_combine(
357 current->cap_bset, current->cap_inheritable
358 );
359 bprm->cap_effective = (bprm->e_uid == 0);
360 ret = 0;
1da177e4 361 }
1da177e4 362 }
b5376771
SH
363
364 return ret;
1da177e4
LT
365}
366
367void cap_bprm_apply_creds (struct linux_binprm *bprm, int unsafe)
368{
3fc689e9
EP
369 kernel_cap_t pP = current->cap_permitted;
370 kernel_cap_t pE = current->cap_effective;
b103c598
DH
371 uid_t uid;
372 gid_t gid;
3fc689e9 373
b103c598
DH
374 current_uid_gid(&uid, &gid);
375
376 if (bprm->e_uid != uid || bprm->e_gid != gid ||
5459c164
AM
377 !cap_issubset(bprm->cap_post_exec_permitted,
378 current->cap_permitted)) {
6c5d5238 379 set_dumpable(current->mm, suid_dumpable);
b5376771 380 current->pdeath_signal = 0;
1da177e4
LT
381
382 if (unsafe & ~LSM_UNSAFE_PTRACE_CAP) {
383 if (!capable(CAP_SETUID)) {
b103c598
DH
384 bprm->e_uid = uid;
385 bprm->e_gid = gid;
1da177e4 386 }
1209726c 387 if (cap_limit_ptraced_target()) {
5459c164
AM
388 bprm->cap_post_exec_permitted = cap_intersect(
389 bprm->cap_post_exec_permitted,
390 current->cap_permitted);
1da177e4
LT
391 }
392 }
393 }
394
395 current->suid = current->euid = current->fsuid = bprm->e_uid;
396 current->sgid = current->egid = current->fsgid = bprm->e_gid;
397
398 /* For init, we want to retain the capabilities set
399 * in the init_task struct. Thus we skip the usual
400 * capability rules */
b460cbc5 401 if (!is_global_init(current)) {
5459c164 402 current->cap_permitted = bprm->cap_post_exec_permitted;
e338d263 403 if (bprm->cap_effective)
5459c164 404 current->cap_effective = bprm->cap_post_exec_permitted;
e338d263
AM
405 else
406 cap_clear(current->cap_effective);
1da177e4
LT
407 }
408
3fc689e9
EP
409 /*
410 * Audit candidate if current->cap_effective is set
411 *
412 * We do not bother to audit if 3 things are true:
413 * 1) cap_effective has all caps
414 * 2) we are root
415 * 3) root is supposed to have all caps (SECURE_NOROOT)
416 * Since this is just a normal root execing a process.
417 *
418 * Number 1 above might fail if you don't have a full bset, but I think
419 * that is interesting information to audit.
420 */
421 if (!cap_isclear(current->cap_effective)) {
422 if (!cap_issubset(CAP_FULL_SET, current->cap_effective) ||
423 (bprm->e_uid != 0) || (current->uid != 0) ||
424 issecure(SECURE_NOROOT))
425 audit_log_bprm_fcaps(bprm, &pP, &pE);
426 }
1da177e4 427
3898b1b4 428 current->securebits &= ~issecure_mask(SECURE_KEEP_CAPS);
1da177e4
LT
429}
430
431int cap_bprm_secureexec (struct linux_binprm *bprm)
432{
b103c598 433 if (current_uid() != 0) {
b5376771
SH
434 if (bprm->cap_effective)
435 return 1;
5459c164 436 if (!cap_isclear(bprm->cap_post_exec_permitted))
b5376771
SH
437 return 1;
438 }
439
b103c598
DH
440 return (current_euid() != current_uid() ||
441 current_egid() != current_gid());
1da177e4
LT
442}
443
8f0cfa52
DH
444int cap_inode_setxattr(struct dentry *dentry, const char *name,
445 const void *value, size_t size, int flags)
1da177e4 446{
b5376771
SH
447 if (!strcmp(name, XATTR_NAME_CAPS)) {
448 if (!capable(CAP_SETFCAP))
449 return -EPERM;
450 return 0;
451 } else if (!strncmp(name, XATTR_SECURITY_PREFIX,
1da177e4
LT
452 sizeof(XATTR_SECURITY_PREFIX) - 1) &&
453 !capable(CAP_SYS_ADMIN))
454 return -EPERM;
455 return 0;
456}
457
8f0cfa52 458int cap_inode_removexattr(struct dentry *dentry, const char *name)
1da177e4 459{
b5376771
SH
460 if (!strcmp(name, XATTR_NAME_CAPS)) {
461 if (!capable(CAP_SETFCAP))
462 return -EPERM;
463 return 0;
464 } else if (!strncmp(name, XATTR_SECURITY_PREFIX,
1da177e4
LT
465 sizeof(XATTR_SECURITY_PREFIX) - 1) &&
466 !capable(CAP_SYS_ADMIN))
467 return -EPERM;
468 return 0;
469}
470
471/* moved from kernel/sys.c. */
472/*
473 * cap_emulate_setxuid() fixes the effective / permitted capabilities of
474 * a process after a call to setuid, setreuid, or setresuid.
475 *
476 * 1) When set*uiding _from_ one of {r,e,s}uid == 0 _to_ all of
477 * {r,e,s}uid != 0, the permitted and effective capabilities are
478 * cleared.
479 *
480 * 2) When set*uiding _from_ euid == 0 _to_ euid != 0, the effective
481 * capabilities of the process are cleared.
482 *
483 * 3) When set*uiding _from_ euid != 0 _to_ euid == 0, the effective
484 * capabilities are set to the permitted capabilities.
485 *
486 * fsuid is handled elsewhere. fsuid == 0 and {r,e,s}uid!= 0 should
487 * never happen.
488 *
489 * -astor
490 *
491 * cevans - New behaviour, Oct '99
492 * A process may, via prctl(), elect to keep its capabilities when it
493 * calls setuid() and switches away from uid==0. Both permitted and
494 * effective sets will be retained.
495 * Without this change, it was impossible for a daemon to drop only some
496 * of its privilege. The call to setuid(!=0) would drop all privileges!
497 * Keeping uid 0 is not an option because uid 0 owns too many vital
498 * files..
499 * Thanks to Olaf Kirch and Peter Benie for spotting this.
500 */
501static inline void cap_emulate_setxuid (int old_ruid, int old_euid,
502 int old_suid)
503{
b103c598
DH
504 uid_t euid = current_euid();
505
1da177e4 506 if ((old_ruid == 0 || old_euid == 0 || old_suid == 0) &&
b103c598 507 (current_uid() != 0 && euid != 0 && current_suid() != 0) &&
3898b1b4 508 !issecure(SECURE_KEEP_CAPS)) {
1da177e4
LT
509 cap_clear (current->cap_permitted);
510 cap_clear (current->cap_effective);
511 }
b103c598 512 if (old_euid == 0 && euid != 0) {
1da177e4
LT
513 cap_clear (current->cap_effective);
514 }
b103c598 515 if (old_euid != 0 && euid == 0) {
1da177e4
LT
516 current->cap_effective = current->cap_permitted;
517 }
518}
519
520int cap_task_post_setuid (uid_t old_ruid, uid_t old_euid, uid_t old_suid,
521 int flags)
522{
523 switch (flags) {
524 case LSM_SETID_RE:
525 case LSM_SETID_ID:
526 case LSM_SETID_RES:
527 /* Copied from kernel/sys.c:setreuid/setuid/setresuid. */
528 if (!issecure (SECURE_NO_SETUID_FIXUP)) {
529 cap_emulate_setxuid (old_ruid, old_euid, old_suid);
530 }
531 break;
532 case LSM_SETID_FS:
533 {
534 uid_t old_fsuid = old_ruid;
535
536 /* Copied from kernel/sys.c:setfsuid. */
537
538 /*
539 * FIXME - is fsuser used for all CAP_FS_MASK capabilities?
540 * if not, we might be a bit too harsh here.
541 */
542
543 if (!issecure (SECURE_NO_SETUID_FIXUP)) {
b103c598 544 if (old_fsuid == 0 && current_fsuid() != 0) {
e338d263
AM
545 current->cap_effective =
546 cap_drop_fs_set(
547 current->cap_effective);
1da177e4 548 }
b103c598 549 if (old_fsuid != 0 && current_fsuid() == 0) {
e338d263
AM
550 current->cap_effective =
551 cap_raise_fs_set(
552 current->cap_effective,
553 current->cap_permitted);
1da177e4
LT
554 }
555 }
556 break;
557 }
558 default:
559 return -EINVAL;
560 }
561
562 return 0;
563}
564
b5376771
SH
565#ifdef CONFIG_SECURITY_FILE_CAPABILITIES
566/*
567 * Rationale: code calling task_setscheduler, task_setioprio, and
568 * task_setnice, assumes that
569 * . if capable(cap_sys_nice), then those actions should be allowed
570 * . if not capable(cap_sys_nice), but acting on your own processes,
571 * then those actions should be allowed
572 * This is insufficient now since you can call code without suid, but
573 * yet with increased caps.
574 * So we check for increased caps on the target process.
575 */
de45e806 576static int cap_safe_nice(struct task_struct *p)
b5376771
SH
577{
578 if (!cap_issubset(p->cap_permitted, current->cap_permitted) &&
5cd9c58f 579 !capable(CAP_SYS_NICE))
b5376771
SH
580 return -EPERM;
581 return 0;
582}
583
584int cap_task_setscheduler (struct task_struct *p, int policy,
585 struct sched_param *lp)
586{
587 return cap_safe_nice(p);
588}
589
590int cap_task_setioprio (struct task_struct *p, int ioprio)
591{
592 return cap_safe_nice(p);
593}
594
595int cap_task_setnice (struct task_struct *p, int nice)
596{
597 return cap_safe_nice(p);
598}
599
3b7391de
SH
600/*
601 * called from kernel/sys.c for prctl(PR_CABSET_DROP)
602 * done without task_capability_lock() because it introduces
603 * no new races - i.e. only another task doing capget() on
604 * this task could get inconsistent info. There can be no
605 * racing writer bc a task can only change its own caps.
606 */
3898b1b4 607static long cap_prctl_drop(unsigned long cap)
3b7391de
SH
608{
609 if (!capable(CAP_SETPCAP))
610 return -EPERM;
611 if (!cap_valid(cap))
612 return -EINVAL;
613 cap_lower(current->cap_bset, cap);
614 return 0;
615}
3898b1b4 616
b5376771
SH
617#else
618int cap_task_setscheduler (struct task_struct *p, int policy,
619 struct sched_param *lp)
620{
621 return 0;
622}
623int cap_task_setioprio (struct task_struct *p, int ioprio)
624{
625 return 0;
626}
627int cap_task_setnice (struct task_struct *p, int nice)
628{
629 return 0;
630}
b5376771
SH
631#endif
632
3898b1b4
AM
633int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3,
634 unsigned long arg4, unsigned long arg5, long *rc_p)
635{
636 long error = 0;
637
638 switch (option) {
639 case PR_CAPBSET_READ:
640 if (!cap_valid(arg2))
641 error = -EINVAL;
642 else
643 error = !!cap_raised(current->cap_bset, arg2);
644 break;
645#ifdef CONFIG_SECURITY_FILE_CAPABILITIES
646 case PR_CAPBSET_DROP:
647 error = cap_prctl_drop(arg2);
648 break;
649
650 /*
651 * The next four prctl's remain to assist with transitioning a
652 * system from legacy UID=0 based privilege (when filesystem
653 * capabilities are not in use) to a system using filesystem
654 * capabilities only - as the POSIX.1e draft intended.
655 *
656 * Note:
657 *
658 * PR_SET_SECUREBITS =
659 * issecure_mask(SECURE_KEEP_CAPS_LOCKED)
660 * | issecure_mask(SECURE_NOROOT)
661 * | issecure_mask(SECURE_NOROOT_LOCKED)
662 * | issecure_mask(SECURE_NO_SETUID_FIXUP)
663 * | issecure_mask(SECURE_NO_SETUID_FIXUP_LOCKED)
664 *
665 * will ensure that the current process and all of its
666 * children will be locked into a pure
667 * capability-based-privilege environment.
668 */
669 case PR_SET_SECUREBITS:
670 if ((((current->securebits & SECURE_ALL_LOCKS) >> 1)
671 & (current->securebits ^ arg2)) /*[1]*/
672 || ((current->securebits & SECURE_ALL_LOCKS
673 & ~arg2)) /*[2]*/
674 || (arg2 & ~(SECURE_ALL_LOCKS | SECURE_ALL_BITS)) /*[3]*/
06112163 675 || (cap_capable(current, CAP_SETPCAP, SECURITY_CAP_AUDIT) != 0)) { /*[4]*/
3898b1b4
AM
676 /*
677 * [1] no changing of bits that are locked
678 * [2] no unlocking of locks
679 * [3] no setting of unsupported bits
680 * [4] doing anything requires privilege (go read about
681 * the "sendmail capabilities bug")
682 */
683 error = -EPERM; /* cannot change a locked bit */
684 } else {
685 current->securebits = arg2;
686 }
687 break;
688 case PR_GET_SECUREBITS:
689 error = current->securebits;
690 break;
691
692#endif /* def CONFIG_SECURITY_FILE_CAPABILITIES */
693
694 case PR_GET_KEEPCAPS:
695 if (issecure(SECURE_KEEP_CAPS))
696 error = 1;
697 break;
698 case PR_SET_KEEPCAPS:
699 if (arg2 > 1) /* Note, we rely on arg2 being unsigned here */
700 error = -EINVAL;
701 else if (issecure(SECURE_KEEP_CAPS_LOCKED))
702 error = -EPERM;
703 else if (arg2)
704 current->securebits |= issecure_mask(SECURE_KEEP_CAPS);
705 else
706 current->securebits &=
707 ~issecure_mask(SECURE_KEEP_CAPS);
708 break;
709
710 default:
711 /* No functionality available - continue with default */
712 return 0;
713 }
714
715 /* Functionality provided */
716 *rc_p = error;
717 return 1;
718}
719
1da177e4
LT
720void cap_task_reparent_to_init (struct task_struct *p)
721{
e338d263
AM
722 cap_set_init_eff(p->cap_effective);
723 cap_clear(p->cap_inheritable);
724 cap_set_full(p->cap_permitted);
3898b1b4 725 p->securebits = SECUREBITS_DEFAULT;
1da177e4
LT
726 return;
727}
728
729int cap_syslog (int type)
730{
731 if ((type != 3 && type != 10) && !capable(CAP_SYS_ADMIN))
732 return -EPERM;
733 return 0;
734}
735
34b4e4aa 736int cap_vm_enough_memory(struct mm_struct *mm, long pages)
1da177e4
LT
737{
738 int cap_sys_admin = 0;
739
06112163 740 if (cap_capable(current, CAP_SYS_ADMIN, SECURITY_CAP_NOAUDIT) == 0)
1da177e4 741 cap_sys_admin = 1;
34b4e4aa 742 return __vm_enough_memory(mm, pages, cap_sys_admin);
1da177e4
LT
743}
744