2 * Copyright 2000, International Business Machines Corporation and others.
5 * This software has been released under the terms of the IBM Public
6 * License. For details, see the LICENSE file in the top-level source
7 * directory or online at http://www.openafs.org/dl/license10.html
17 * afs_get_pag_from_groups
18 * afs_get_groups_from_pag
22 #include <afsconfig.h>
23 #include "afs/param.h"
28 #include "afs/sysincludes.h" /* Standard vendor system headers */
29 #include "afsincludes.h" /* Afs-based standard headers */
30 #include "afs/afs_stats.h" /* statistics */
31 #include "afs/afs_cbqueue.h"
32 #include "afs/nfsclient.h"
33 #include "afs/afs_osidnlc.h"
36 /* Imported variables */
37 extern int afs_shuttingdown;
39 /* Exported variables */
41 #if defined(UKERNEL) && defined(AFS_WEB_ENHANCEMENTS)
42 afs_uint32 pagCounter = 1;
44 afs_uint32 pagCounter = 0;
45 #endif /* UKERNEL && AFS_WEB_ENHANCEMENTS */
47 #ifdef AFS_LINUX26_ONEGROUP_ENV
48 #define NUMPAGGROUPS 1
50 #define NUMPAGGROUPS 2
55 * Pags are implemented as follows: the set of groups whose long
56 * representation is '41XXXXXX' hex are used to represent the pags.
57 * Being a member of such a group means you are authenticated as pag
58 * XXXXXX (0x41 == 'A', for Andrew). You are never authenticated as
59 * multiple pags at once.
61 * The function afs_InitReq takes a credential field and formats the
62 * corresponding venus request structure. The uid field in the
63 * vrequest structure is set to the *pag* you are authenticated as, or
64 * the uid, if you aren't authenticated with a pag.
66 * The basic motivation behind pags is this: just because your unix
67 * uid is N doesn't mean that you should have the same privileges as
68 * anyone logged in on the machine as user N, since this would enable
69 * the superuser on the machine to sneak in and make use of anyone's
70 * authentication info, even that which is only accidentally left
71 * behind when someone leaves a public workstation.
73 * AFS doesn't use the unix uid for anything except
74 * a handle with which to find the actual authentication tokens
75 * anyway, so the pag is an alternative handle which is somewhat more
76 * secure (although of course not absolutely secure).
78 #if !defined(UKERNEL) || !defined(AFS_WEB_ENHANCEMENTS)
83 #ifdef AFS_LINUX20_ENV
84 /* Ensure unique PAG's (mod 200 days) when reloading the client. */
85 return (('A' << 24) + ((pag_epoch + pagCounter++) & 0xffffff));
86 #else /* AFS_LINUX20_ENV */
87 return (('A' << 24) + (pagCounter++ & 0xffffff));
88 #endif /* AFS_LINUX20_ENV */
95 #ifdef AFS_LINUX20_ENV
96 /* Ensure unique PAG's (mod 200 days) when reloading the client. */
97 return (('A' << 24) + ((pag_epoch + pagCounter) & 0xffffff));
99 return (('A' << 24) + (pagCounter & 0xffffff));
105 /* Web enhancement: we don't need to restrict pags to 41XXXXXX since
106 * we are not sharing the space with anyone. So we use the full 32 bits. */
112 #ifdef AFS_LINUX20_ENV
113 return (pag_epoch + pagCounter++);
115 return (pagCounter++);
116 #endif /* AFS_LINUX20_ENV */
123 #ifdef AFS_LINUX20_ENV
124 /* Ensure unique PAG's (mod 200 days) when reloading the client. */
125 return (pag_epoch + pagCounter);
130 #endif /* UKERNEL && AFS_WEB_ENHANCEMENTS */
132 /* used to require 10 seconds between each setpag to guarantee that
133 * PAGs never wrap - which would be a security hole. If we presume
134 * that in ordinary operation, the average rate of PAG allocation
135 * will not exceed one per second, the 24 bits provided will be
136 * sufficient for ~200 days. Unfortunately, if we merely assume that,
137 * there will be an opportunity for attack. So we must enforce it.
138 * If we need to increase the average rate of PAG allocation, we
139 * should increase the number of bits in a PAG, and/or reduce our
140 * window in which we guarantee that the PAG counter won't wrap.
141 * By permitting an average of one new PAG per second, new PAGs can
142 * be allocated VERY frequently over a short period relative to total uptime.
143 * Of course, there's only an issue here if one user stays logged (and re-
144 * activates tokens repeatedly) for that entire period.
147 static int afs_pag_sleepcnt = 0;
150 afs_pag_sleep(struct AFS_UCRED **acred)
154 if (!afs_suser(acred)) {
155 if(osi_Time() - pag_epoch < pagCounter) {
164 afs_pag_wait(struct AFS_UCRED **acred)
166 if (afs_pag_sleep(acred)) {
167 if (!afs_pag_sleepcnt) {
168 printf("%s() PAG throttling triggered, pid %d... sleeping. sleepcnt %d\n",
169 "afs_pag_wait", osi_getpid(), afs_pag_sleepcnt);
175 /* XXX spins on EINTR */
176 afs_osi_Wait(1000, (struct afs_osi_WaitHandle *)0, 0);
177 } while (afs_pag_sleep(acred));
186 #if defined(AFS_SUN5_ENV)
187 afs_setpag(struct AFS_UCRED **credpp)
188 #elif defined(AFS_OSF_ENV) || defined(AFS_DARWIN_ENV) || defined(AFS_XBSD_ENV)
189 afs_setpag(struct proc *p, void *args, int *retval)
195 #if defined(AFS_SUN5_ENV)
196 struct AFS_UCRED **acred = *credpp;
197 #elif defined(AFS_OBSD_ENV)
198 struct AFS_UCRED **acred = &p->p_ucred;
200 struct AFS_UCRED **acred = NULL;
205 #if defined(AFS_SGI53_ENV) && defined(MP)
206 /* This is our first chance to get the global lock. */
208 #endif /* defined(AFS_SGI53_ENV) && defined(MP) */
210 AFS_STATCNT(afs_setpag);
215 #if defined(AFS_SUN5_ENV)
216 code = AddPag(genpag(), credpp);
217 #elif defined(AFS_OSF_ENV) || defined(AFS_XBSD_ENV)
218 code = AddPag(p, genpag(), &p->p_rcred);
219 #elif defined(AFS_AIX41_ENV)
222 struct ucred *credp0;
226 code = AddPag(genpag(), &credp);
227 /* If AddPag() didn't make a new cred, then free our cred ref */
228 if (credp == credp0) {
232 #elif defined(AFS_HPUX110_ENV)
234 struct ucred *credp = p_cred(u.u_procp);
235 code = AddPag(genpag(), &credp);
237 #elif defined(AFS_SGI_ENV)
240 credp = OSI_GET_CURRENT_CRED();
241 code = AddPag(genpag(), &credp);
243 #elif defined(AFS_LINUX20_ENV)
245 struct AFS_UCRED *credp = crref();
246 code = AddPag(genpag(), &credp);
249 #elif defined(AFS_DARWIN80_ENV)
251 struct ucred *credp = kauth_cred_proc_ref(p);
252 code = AddPag(p, genpag(), &credp);
253 kauth_cred_rele(credp);
255 #elif defined(AFS_DARWIN_ENV)
257 struct ucred *credp = crdup(p->p_cred->pc_ucred);
258 code = AddPag(p, genpag(), &credp);
262 code = AddPag(genpag(), &u.u_cred);
265 afs_Trace1(afs_iclSetp, CM_TRACE_SETPAG, ICL_TYPE_INT32, code);
267 #if defined(KERNEL_HAVE_UERROR)
272 #if defined(AFS_SGI53_ENV) && defined(MP)
274 #endif /* defined(AFS_SGI53_ENV) && defined(MP) */
279 #if defined(UKERNEL) && defined(AFS_WEB_ENHANCEMENTS)
282 * This function is like setpag but sets the current thread's pag id to a
283 * caller-provided value instead of calling genpag(). This implements a
284 * form of token caching since the caller can recall a particular pag value
285 * for the thread to restore tokens, rather than reauthenticating.
288 #if defined(AFS_SUN5_ENV)
289 afs_setpag_val(struct AFS_UCRED **credpp, int pagval)
290 #elif defined(AFS_OSF_ENV) || defined(AFS_DARWIN_ENV) || defined(AFS_XBSD_ENV)
291 afs_setpag_val(struct proc *p, void *args, int *retval, int pagval)
293 afs_setpag_val(int pagval)
297 #if defined(AFS_SUN5_ENV)
298 struct AFS_UCRED **acred = *credp;
299 #elif defined(AFS_OBSD_ENV)
300 struct AFS_UCRED **acred = &p->p_ucred;
302 struct AFS_UCRED **acred = NULL;
307 #if defined(AFS_SGI53_ENV) && defined(MP)
308 /* This is our first chance to get the global lock. */
310 #endif /* defined(AFS_SGI53_ENV) && defined(MP) */
312 AFS_STATCNT(afs_setpag);
316 #if defined(AFS_SUN5_ENV)
317 code = AddPag(pagval, credpp);
318 #elif defined(AFS_OSF_ENV) || defined(AFS_XBSD_ENV)
319 code = AddPag(p, pagval, &p->p_rcred);
320 #elif defined(AFS_AIX41_ENV)
323 struct ucred *credp0;
327 code = AddPag(pagval, &credp);
328 /* If AddPag() didn't make a new cred, then free our cred ref */
329 if (credp == credp0) {
333 #elif defined(AFS_HPUX110_ENV)
335 struct ucred *credp = p_cred(u.u_procp);
336 code = AddPag(pagval, &credp);
338 #elif defined(AFS_SGI_ENV)
341 credp = OSI_GET_CURRENT_CRED();
342 code = AddPag(pagval, &credp);
344 #elif defined(AFS_LINUX20_ENV)
346 struct AFS_UCRED *credp = crref();
347 code = AddPag(pagval, &credp);
350 #elif defined(AFS_DARWIN_ENV)
352 struct ucred *credp = crdup(p->p_cred->pc_ucred);
353 code = AddPag(p, pagval, &credp);
357 code = AddPag(pagval, &u.u_cred);
360 afs_Trace1(afs_iclSetp, CM_TRACE_SETPAG, ICL_TYPE_INT32, code);
361 #if defined(KERNEL_HAVE_UERROR)
365 #if defined(AFS_SGI53_ENV) && defined(MP)
367 #endif /* defined(AFS_SGI53_ENV) && defined(MP) */
371 #ifndef AFS_LINUX26_ONEGROUP_ENV
376 struct AFS_UCRED *credp = u.u_cred;
377 gid_t gidset0, gidset1;
378 #ifdef AFS_SUN510_ENV
381 gids = crgetgroups(*credp);
385 gidset0 = credp->cr_groups[0];
386 gidset1 = credp->cr_groups[1];
388 pagvalue = afs_get_pag_from_groups(gidset0, gidset1);
392 #endif /* UKERNEL && AFS_WEB_ENHANCEMENTS */
395 /* Note - needs to be available on AIX, others can be static - rework this */
396 #if defined(AFS_OSF_ENV) || defined(AFS_DARWIN_ENV) || defined(AFS_XBSD_ENV)
398 AddPag(struct proc *p, afs_int32 aval, struct AFS_UCRED **credpp)
401 AddPag(afs_int32 aval, struct AFS_UCRED **credpp)
404 afs_int32 newpag, code;
407 #if defined(AFS_OSF_ENV) || defined(AFS_DARWIN_ENV) || defined(AFS_XBSD_ENV)
408 if ((code = setpag(p, credpp, aval, &newpag, 0)))
410 if ((code = setpag(credpp, aval, &newpag, 0)))
412 #if defined(KERNEL_HAVE_UERROR)
413 return (setuerror(code), code);
422 afs_InitReq(register struct vrequest *av, struct AFS_UCRED *acred)
426 AFS_STATCNT(afs_InitReq);
427 memset(av, 0, sizeof(*av));
428 if (afs_shuttingdown)
431 #ifdef AFS_LINUX26_ENV
432 #if !defined(AFS_NONFSTRANS)
433 if (osi_linux_nfs_initreq(av, acred, &code))
438 av->uid = PagInCred(acred);
439 if (av->uid == NOPAG) {
440 /* Afs doesn't use the unix uid for anuthing except a handle
441 * with which to find the actual authentication tokens so I
442 * think it's ok to use the real uid to make setuid
443 * programs (without setpag) to work properly.
445 #if defined(AFS_DARWIN_ENV) || defined(AFS_XBSD_ENV)
447 av->uid = -2; /* XXX nobody... ? */
449 av->uid = acred->cr_uid; /* bsd creds don't have ruid */
450 #elif defined(AFS_SUN510_ENV)
451 av->uid = crgetruid(acred);
453 av->uid = acred->cr_ruid; /* default when no pag is set */
461 #ifdef AFS_LINUX26_ONEGROUP_ENV
463 afs_get_pag_from_groups(struct group_info *group_info)
468 AFS_STATCNT(afs_get_pag_from_groups);
469 for (i = 0; (i < group_info->ngroups &&
470 (g0 = GROUP_AT(group_info, i)) != (gid_t) NOGROUP); i++) {
471 if (((g0 >> 24) & 0xff) == 'A')
478 afs_get_pag_from_groups(gid_t g0a, gid_t g1a)
482 afs_uint32 h, l, ret;
484 AFS_STATCNT(afs_get_pag_from_groups);
488 if (g0 < 0xc000 && g1 < 0xc000) {
489 l = ((g0 & 0x3fff) << 14) | (g1 & 0x3fff);
491 h = (g1 >> 14) + h + h + h;
492 ret = ((h << 28) | l);
493 #if defined(UKERNEL) && defined(AFS_WEB_ENHANCEMENTS)
496 /* Additional testing */
497 if (((ret >> 24) & 0xff) == 'A')
499 #endif /* UKERNEL && AFS_WEB_ENHANCEMENTS */
506 afs_get_groups_from_pag(afs_uint32 pag, gid_t * g0p, gid_t * g1p)
508 unsigned short g0, g1;
511 AFS_STATCNT(afs_get_groups_from_pag);
512 #ifdef AFS_LINUX26_ONEGROUP_ENV
516 #if !defined(UKERNEL) || !defined(AFS_WEB_ENHANCEMENTS)
518 #endif /* UKERNEL && AFS_WEB_ENHANCEMENTS */
519 g0 = 0x3fff & (pag >> 14);
521 g0 |= ((pag >> 28) / 3) << 14;
522 g1 |= ((pag >> 28) % 3) << 14;
530 PagInCred(const struct AFS_UCRED *cred)
534 #if defined(AFS_SUN510_ENV)
539 AFS_STATCNT(PagInCred);
540 if (cred == NULL || cred == afs_osi_credp) {
543 #if defined(AFS_SUN510_ENV)
544 gids = crgetgroups(cred);
545 ngroups = crgetngroups(cred);
547 #if defined(AFS_DARWIN_ENV) || defined(AFS_XBSD_ENV)
548 if (cred == NOCRED || cred == FSCRED) {
551 if (cred->cr_ngroups < 3)
553 /* gid is stored in cr_groups[0] */
554 g0 = cred->cr_groups[1];
555 g1 = cred->cr_groups[2];
557 #if defined(AFS_AIX51_ENV)
558 if (kcred_getpag(cred, PAG_AFS, &pag) < 0 || pag == 0)
561 #elif defined(AFS_AIX_ENV)
562 if (cred->cr_ngrps < 2) {
565 #elif defined(AFS_LINUX26_ENV)
566 if (cred->cr_group_info->ngroups < NUMPAGGROUPS) {
570 #elif defined(AFS_SGI_ENV) || defined(AFS_SUN5_ENV) || defined(AFS_DUX40_ENV) || defined(AFS_LINUX20_ENV) || defined(AFS_XBSD_ENV)
571 #if defined(AFS_SUN510_ENV)
574 if (cred->cr_ngroups < 2) {
580 #if defined(AFS_AIX51_ENV)
581 g0 = cred->cr_groupset.gs_union.un_groups[0];
582 g1 = cred->cr_groupset.gs_union.un_groups[1];
583 #elif defined(AFS_LINUX26_ONEGROUP_ENV)
584 #elif defined(AFS_LINUX26_ENV)
585 g0 = GROUP_AT(cred->cr_group_info, 0);
586 g1 = GROUP_AT(cred->cr_group_info, 1);
587 #elif defined(AFS_SUN510_ENV)
591 g0 = cred->cr_groups[0];
592 g1 = cred->cr_groups[1];
595 #if defined(AFS_LINUX26_ONEGROUP_ENV)
596 pag = (afs_int32) afs_get_pag_from_groups(cred->cr_group_info);
598 pag = (afs_int32) afs_get_pag_from_groups(g0, g1);
601 #if defined(AFS_LINUX26_ENV) && defined(LINUX_KEYRING_SUPPORT)
604 afs_uint32 upag, newpag;
606 key = request_key(&key_type_afs_pag, "_pag", NULL);
608 if (key_validate(key) == 0 && key->uid == 0) { /* also verify in the session keyring? */
609 upag = (afs_uint32) key->payload.value;
610 if (((upag >> 24) & 0xff) == 'A') {
611 __setpag(&cred, upag, &newpag, 0);
612 pag = (afs_int32) upag;