ring-buffer: fix deadlock from reader_lock in read_start
[linux-2.6] / net / sunrpc / svcauth_unix.c
1 #include <linux/types.h>
2 #include <linux/sched.h>
3 #include <linux/module.h>
4 #include <linux/sunrpc/types.h>
5 #include <linux/sunrpc/xdr.h>
6 #include <linux/sunrpc/svcsock.h>
7 #include <linux/sunrpc/svcauth.h>
8 #include <linux/sunrpc/gss_api.h>
9 #include <linux/err.h>
10 #include <linux/seq_file.h>
11 #include <linux/hash.h>
12 #include <linux/string.h>
13 #include <net/sock.h>
14 #include <net/ipv6.h>
15 #include <linux/kernel.h>
16 #define RPCDBG_FACILITY RPCDBG_AUTH
17
18
19 /*
20  * AUTHUNIX and AUTHNULL credentials are both handled here.
21  * AUTHNULL is treated just like AUTHUNIX except that the uid/gid
22  * are always nobody (-2).  i.e. we do the same IP address checks for
23  * AUTHNULL as for AUTHUNIX, and that is done here.
24  */
25
26
27 struct unix_domain {
28         struct auth_domain      h;
29         int     addr_changes;
30         /* other stuff later */
31 };
32
33 extern struct auth_ops svcauth_unix;
34
35 struct auth_domain *unix_domain_find(char *name)
36 {
37         struct auth_domain *rv;
38         struct unix_domain *new = NULL;
39
40         rv = auth_domain_lookup(name, NULL);
41         while(1) {
42                 if (rv) {
43                         if (new && rv != &new->h)
44                                 auth_domain_put(&new->h);
45
46                         if (rv->flavour != &svcauth_unix) {
47                                 auth_domain_put(rv);
48                                 return NULL;
49                         }
50                         return rv;
51                 }
52
53                 new = kmalloc(sizeof(*new), GFP_KERNEL);
54                 if (new == NULL)
55                         return NULL;
56                 kref_init(&new->h.ref);
57                 new->h.name = kstrdup(name, GFP_KERNEL);
58                 if (new->h.name == NULL) {
59                         kfree(new);
60                         return NULL;
61                 }
62                 new->h.flavour = &svcauth_unix;
63                 new->addr_changes = 0;
64                 rv = auth_domain_lookup(name, &new->h);
65         }
66 }
67 EXPORT_SYMBOL(unix_domain_find);
68
69 static void svcauth_unix_domain_release(struct auth_domain *dom)
70 {
71         struct unix_domain *ud = container_of(dom, struct unix_domain, h);
72
73         kfree(dom->name);
74         kfree(ud);
75 }
76
77
78 /**************************************************
79  * cache for IP address to unix_domain
80  * as needed by AUTH_UNIX
81  */
82 #define IP_HASHBITS     8
83 #define IP_HASHMAX      (1<<IP_HASHBITS)
84 #define IP_HASHMASK     (IP_HASHMAX-1)
85
86 struct ip_map {
87         struct cache_head       h;
88         char                    m_class[8]; /* e.g. "nfsd" */
89         struct in6_addr         m_addr;
90         struct unix_domain      *m_client;
91         int                     m_add_change;
92 };
93 static struct cache_head        *ip_table[IP_HASHMAX];
94
95 static void ip_map_put(struct kref *kref)
96 {
97         struct cache_head *item = container_of(kref, struct cache_head, ref);
98         struct ip_map *im = container_of(item, struct ip_map,h);
99
100         if (test_bit(CACHE_VALID, &item->flags) &&
101             !test_bit(CACHE_NEGATIVE, &item->flags))
102                 auth_domain_put(&im->m_client->h);
103         kfree(im);
104 }
105
106 #if IP_HASHBITS == 8
107 /* hash_long on a 64 bit machine is currently REALLY BAD for
108  * IP addresses in reverse-endian (i.e. on a little-endian machine).
109  * So use a trivial but reliable hash instead
110  */
111 static inline int hash_ip(__be32 ip)
112 {
113         int hash = (__force u32)ip ^ ((__force u32)ip>>16);
114         return (hash ^ (hash>>8)) & 0xff;
115 }
116 #endif
117 static inline int hash_ip6(struct in6_addr ip)
118 {
119         return (hash_ip(ip.s6_addr32[0]) ^
120                 hash_ip(ip.s6_addr32[1]) ^
121                 hash_ip(ip.s6_addr32[2]) ^
122                 hash_ip(ip.s6_addr32[3]));
123 }
124 static int ip_map_match(struct cache_head *corig, struct cache_head *cnew)
125 {
126         struct ip_map *orig = container_of(corig, struct ip_map, h);
127         struct ip_map *new = container_of(cnew, struct ip_map, h);
128         return strcmp(orig->m_class, new->m_class) == 0
129                 && ipv6_addr_equal(&orig->m_addr, &new->m_addr);
130 }
131 static void ip_map_init(struct cache_head *cnew, struct cache_head *citem)
132 {
133         struct ip_map *new = container_of(cnew, struct ip_map, h);
134         struct ip_map *item = container_of(citem, struct ip_map, h);
135
136         strcpy(new->m_class, item->m_class);
137         ipv6_addr_copy(&new->m_addr, &item->m_addr);
138 }
139 static void update(struct cache_head *cnew, struct cache_head *citem)
140 {
141         struct ip_map *new = container_of(cnew, struct ip_map, h);
142         struct ip_map *item = container_of(citem, struct ip_map, h);
143
144         kref_get(&item->m_client->h.ref);
145         new->m_client = item->m_client;
146         new->m_add_change = item->m_add_change;
147 }
148 static struct cache_head *ip_map_alloc(void)
149 {
150         struct ip_map *i = kmalloc(sizeof(*i), GFP_KERNEL);
151         if (i)
152                 return &i->h;
153         else
154                 return NULL;
155 }
156
157 static void ip_map_request(struct cache_detail *cd,
158                                   struct cache_head *h,
159                                   char **bpp, int *blen)
160 {
161         char text_addr[40];
162         struct ip_map *im = container_of(h, struct ip_map, h);
163
164         if (ipv6_addr_v4mapped(&(im->m_addr))) {
165                 snprintf(text_addr, 20, NIPQUAD_FMT,
166                                 ntohl(im->m_addr.s6_addr32[3]) >> 24 & 0xff,
167                                 ntohl(im->m_addr.s6_addr32[3]) >> 16 & 0xff,
168                                 ntohl(im->m_addr.s6_addr32[3]) >>  8 & 0xff,
169                                 ntohl(im->m_addr.s6_addr32[3]) >>  0 & 0xff);
170         } else {
171                 snprintf(text_addr, 40, NIP6_FMT, NIP6(im->m_addr));
172         }
173         qword_add(bpp, blen, im->m_class);
174         qword_add(bpp, blen, text_addr);
175         (*bpp)[-1] = '\n';
176 }
177
178 static struct ip_map *ip_map_lookup(char *class, struct in6_addr *addr);
179 static int ip_map_update(struct ip_map *ipm, struct unix_domain *udom, time_t expiry);
180
181 static int ip_map_parse(struct cache_detail *cd,
182                           char *mesg, int mlen)
183 {
184         /* class ipaddress [domainname] */
185         /* should be safe just to use the start of the input buffer
186          * for scratch: */
187         char *buf = mesg;
188         int len;
189         int b1, b2, b3, b4, b5, b6, b7, b8;
190         char c;
191         char class[8];
192         struct in6_addr addr;
193         int err;
194
195         struct ip_map *ipmp;
196         struct auth_domain *dom;
197         time_t expiry;
198
199         if (mesg[mlen-1] != '\n')
200                 return -EINVAL;
201         mesg[mlen-1] = 0;
202
203         /* class */
204         len = qword_get(&mesg, class, sizeof(class));
205         if (len <= 0) return -EINVAL;
206
207         /* ip address */
208         len = qword_get(&mesg, buf, mlen);
209         if (len <= 0) return -EINVAL;
210
211         if (sscanf(buf, NIPQUAD_FMT "%c", &b1, &b2, &b3, &b4, &c) == 4) {
212                 addr.s6_addr32[0] = 0;
213                 addr.s6_addr32[1] = 0;
214                 addr.s6_addr32[2] = htonl(0xffff);
215                 addr.s6_addr32[3] =
216                         htonl((((((b1<<8)|b2)<<8)|b3)<<8)|b4);
217        } else if (sscanf(buf, NIP6_FMT "%c",
218                         &b1, &b2, &b3, &b4, &b5, &b6, &b7, &b8, &c) == 8) {
219                 addr.s6_addr16[0] = htons(b1);
220                 addr.s6_addr16[1] = htons(b2);
221                 addr.s6_addr16[2] = htons(b3);
222                 addr.s6_addr16[3] = htons(b4);
223                 addr.s6_addr16[4] = htons(b5);
224                 addr.s6_addr16[5] = htons(b6);
225                 addr.s6_addr16[6] = htons(b7);
226                 addr.s6_addr16[7] = htons(b8);
227        } else
228                 return -EINVAL;
229
230         expiry = get_expiry(&mesg);
231         if (expiry ==0)
232                 return -EINVAL;
233
234         /* domainname, or empty for NEGATIVE */
235         len = qword_get(&mesg, buf, mlen);
236         if (len < 0) return -EINVAL;
237
238         if (len) {
239                 dom = unix_domain_find(buf);
240                 if (dom == NULL)
241                         return -ENOENT;
242         } else
243                 dom = NULL;
244
245         ipmp = ip_map_lookup(class, &addr);
246         if (ipmp) {
247                 err = ip_map_update(ipmp,
248                              container_of(dom, struct unix_domain, h),
249                              expiry);
250         } else
251                 err = -ENOMEM;
252
253         if (dom)
254                 auth_domain_put(dom);
255
256         cache_flush();
257         return err;
258 }
259
260 static int ip_map_show(struct seq_file *m,
261                        struct cache_detail *cd,
262                        struct cache_head *h)
263 {
264         struct ip_map *im;
265         struct in6_addr addr;
266         char *dom = "-no-domain-";
267
268         if (h == NULL) {
269                 seq_puts(m, "#class IP domain\n");
270                 return 0;
271         }
272         im = container_of(h, struct ip_map, h);
273         /* class addr domain */
274         ipv6_addr_copy(&addr, &im->m_addr);
275
276         if (test_bit(CACHE_VALID, &h->flags) &&
277             !test_bit(CACHE_NEGATIVE, &h->flags))
278                 dom = im->m_client->h.name;
279
280         if (ipv6_addr_v4mapped(&addr)) {
281                 seq_printf(m, "%s " NIPQUAD_FMT " %s\n",
282                         im->m_class,
283                         ntohl(addr.s6_addr32[3]) >> 24 & 0xff,
284                         ntohl(addr.s6_addr32[3]) >> 16 & 0xff,
285                         ntohl(addr.s6_addr32[3]) >>  8 & 0xff,
286                         ntohl(addr.s6_addr32[3]) >>  0 & 0xff,
287                         dom);
288         } else {
289                 seq_printf(m, "%s " NIP6_FMT " %s\n",
290                         im->m_class, NIP6(addr), dom);
291         }
292         return 0;
293 }
294
295
296 struct cache_detail ip_map_cache = {
297         .owner          = THIS_MODULE,
298         .hash_size      = IP_HASHMAX,
299         .hash_table     = ip_table,
300         .name           = "auth.unix.ip",
301         .cache_put      = ip_map_put,
302         .cache_request  = ip_map_request,
303         .cache_parse    = ip_map_parse,
304         .cache_show     = ip_map_show,
305         .match          = ip_map_match,
306         .init           = ip_map_init,
307         .update         = update,
308         .alloc          = ip_map_alloc,
309 };
310
311 static struct ip_map *ip_map_lookup(char *class, struct in6_addr *addr)
312 {
313         struct ip_map ip;
314         struct cache_head *ch;
315
316         strcpy(ip.m_class, class);
317         ipv6_addr_copy(&ip.m_addr, addr);
318         ch = sunrpc_cache_lookup(&ip_map_cache, &ip.h,
319                                  hash_str(class, IP_HASHBITS) ^
320                                  hash_ip6(*addr));
321
322         if (ch)
323                 return container_of(ch, struct ip_map, h);
324         else
325                 return NULL;
326 }
327
328 static int ip_map_update(struct ip_map *ipm, struct unix_domain *udom, time_t expiry)
329 {
330         struct ip_map ip;
331         struct cache_head *ch;
332
333         ip.m_client = udom;
334         ip.h.flags = 0;
335         if (!udom)
336                 set_bit(CACHE_NEGATIVE, &ip.h.flags);
337         else {
338                 ip.m_add_change = udom->addr_changes;
339                 /* if this is from the legacy set_client system call,
340                  * we need m_add_change to be one higher
341                  */
342                 if (expiry == NEVER)
343                         ip.m_add_change++;
344         }
345         ip.h.expiry_time = expiry;
346         ch = sunrpc_cache_update(&ip_map_cache,
347                                  &ip.h, &ipm->h,
348                                  hash_str(ipm->m_class, IP_HASHBITS) ^
349                                  hash_ip6(ipm->m_addr));
350         if (!ch)
351                 return -ENOMEM;
352         cache_put(ch, &ip_map_cache);
353         return 0;
354 }
355
356 int auth_unix_add_addr(struct in6_addr *addr, struct auth_domain *dom)
357 {
358         struct unix_domain *udom;
359         struct ip_map *ipmp;
360
361         if (dom->flavour != &svcauth_unix)
362                 return -EINVAL;
363         udom = container_of(dom, struct unix_domain, h);
364         ipmp = ip_map_lookup("nfsd", addr);
365
366         if (ipmp)
367                 return ip_map_update(ipmp, udom, NEVER);
368         else
369                 return -ENOMEM;
370 }
371 EXPORT_SYMBOL(auth_unix_add_addr);
372
373 int auth_unix_forget_old(struct auth_domain *dom)
374 {
375         struct unix_domain *udom;
376
377         if (dom->flavour != &svcauth_unix)
378                 return -EINVAL;
379         udom = container_of(dom, struct unix_domain, h);
380         udom->addr_changes++;
381         return 0;
382 }
383 EXPORT_SYMBOL(auth_unix_forget_old);
384
385 struct auth_domain *auth_unix_lookup(struct in6_addr *addr)
386 {
387         struct ip_map *ipm;
388         struct auth_domain *rv;
389
390         ipm = ip_map_lookup("nfsd", addr);
391
392         if (!ipm)
393                 return NULL;
394         if (cache_check(&ip_map_cache, &ipm->h, NULL))
395                 return NULL;
396
397         if ((ipm->m_client->addr_changes - ipm->m_add_change) >0) {
398                 if (test_and_set_bit(CACHE_NEGATIVE, &ipm->h.flags) == 0)
399                         auth_domain_put(&ipm->m_client->h);
400                 rv = NULL;
401         } else {
402                 rv = &ipm->m_client->h;
403                 kref_get(&rv->ref);
404         }
405         cache_put(&ipm->h, &ip_map_cache);
406         return rv;
407 }
408 EXPORT_SYMBOL(auth_unix_lookup);
409
410 void svcauth_unix_purge(void)
411 {
412         cache_purge(&ip_map_cache);
413 }
414 EXPORT_SYMBOL(svcauth_unix_purge);
415
416 static inline struct ip_map *
417 ip_map_cached_get(struct svc_rqst *rqstp)
418 {
419         struct ip_map *ipm = NULL;
420         struct svc_xprt *xprt = rqstp->rq_xprt;
421
422         if (test_bit(XPT_CACHE_AUTH, &xprt->xpt_flags)) {
423                 spin_lock(&xprt->xpt_lock);
424                 ipm = xprt->xpt_auth_cache;
425                 if (ipm != NULL) {
426                         if (!cache_valid(&ipm->h)) {
427                                 /*
428                                  * The entry has been invalidated since it was
429                                  * remembered, e.g. by a second mount from the
430                                  * same IP address.
431                                  */
432                                 xprt->xpt_auth_cache = NULL;
433                                 spin_unlock(&xprt->xpt_lock);
434                                 cache_put(&ipm->h, &ip_map_cache);
435                                 return NULL;
436                         }
437                         cache_get(&ipm->h);
438                 }
439                 spin_unlock(&xprt->xpt_lock);
440         }
441         return ipm;
442 }
443
444 static inline void
445 ip_map_cached_put(struct svc_rqst *rqstp, struct ip_map *ipm)
446 {
447         struct svc_xprt *xprt = rqstp->rq_xprt;
448
449         if (test_bit(XPT_CACHE_AUTH, &xprt->xpt_flags)) {
450                 spin_lock(&xprt->xpt_lock);
451                 if (xprt->xpt_auth_cache == NULL) {
452                         /* newly cached, keep the reference */
453                         xprt->xpt_auth_cache = ipm;
454                         ipm = NULL;
455                 }
456                 spin_unlock(&xprt->xpt_lock);
457         }
458         if (ipm)
459                 cache_put(&ipm->h, &ip_map_cache);
460 }
461
462 void
463 svcauth_unix_info_release(void *info)
464 {
465         struct ip_map *ipm = info;
466         cache_put(&ipm->h, &ip_map_cache);
467 }
468
469 /****************************************************************************
470  * auth.unix.gid cache
471  * simple cache to map a UID to a list of GIDs
472  * because AUTH_UNIX aka AUTH_SYS has a max of 16
473  */
474 #define GID_HASHBITS    8
475 #define GID_HASHMAX     (1<<GID_HASHBITS)
476 #define GID_HASHMASK    (GID_HASHMAX - 1)
477
478 struct unix_gid {
479         struct cache_head       h;
480         uid_t                   uid;
481         struct group_info       *gi;
482 };
483 static struct cache_head        *gid_table[GID_HASHMAX];
484
485 static void unix_gid_put(struct kref *kref)
486 {
487         struct cache_head *item = container_of(kref, struct cache_head, ref);
488         struct unix_gid *ug = container_of(item, struct unix_gid, h);
489         if (test_bit(CACHE_VALID, &item->flags) &&
490             !test_bit(CACHE_NEGATIVE, &item->flags))
491                 put_group_info(ug->gi);
492         kfree(ug);
493 }
494
495 static int unix_gid_match(struct cache_head *corig, struct cache_head *cnew)
496 {
497         struct unix_gid *orig = container_of(corig, struct unix_gid, h);
498         struct unix_gid *new = container_of(cnew, struct unix_gid, h);
499         return orig->uid == new->uid;
500 }
501 static void unix_gid_init(struct cache_head *cnew, struct cache_head *citem)
502 {
503         struct unix_gid *new = container_of(cnew, struct unix_gid, h);
504         struct unix_gid *item = container_of(citem, struct unix_gid, h);
505         new->uid = item->uid;
506 }
507 static void unix_gid_update(struct cache_head *cnew, struct cache_head *citem)
508 {
509         struct unix_gid *new = container_of(cnew, struct unix_gid, h);
510         struct unix_gid *item = container_of(citem, struct unix_gid, h);
511
512         get_group_info(item->gi);
513         new->gi = item->gi;
514 }
515 static struct cache_head *unix_gid_alloc(void)
516 {
517         struct unix_gid *g = kmalloc(sizeof(*g), GFP_KERNEL);
518         if (g)
519                 return &g->h;
520         else
521                 return NULL;
522 }
523
524 static void unix_gid_request(struct cache_detail *cd,
525                              struct cache_head *h,
526                              char **bpp, int *blen)
527 {
528         char tuid[20];
529         struct unix_gid *ug = container_of(h, struct unix_gid, h);
530
531         snprintf(tuid, 20, "%u", ug->uid);
532         qword_add(bpp, blen, tuid);
533         (*bpp)[-1] = '\n';
534 }
535
536 static struct unix_gid *unix_gid_lookup(uid_t uid);
537 extern struct cache_detail unix_gid_cache;
538
539 static int unix_gid_parse(struct cache_detail *cd,
540                         char *mesg, int mlen)
541 {
542         /* uid expiry Ngid gid0 gid1 ... gidN-1 */
543         int uid;
544         int gids;
545         int rv;
546         int i;
547         int err;
548         time_t expiry;
549         struct unix_gid ug, *ugp;
550
551         if (mlen <= 0 || mesg[mlen-1] != '\n')
552                 return -EINVAL;
553         mesg[mlen-1] = 0;
554
555         rv = get_int(&mesg, &uid);
556         if (rv)
557                 return -EINVAL;
558         ug.uid = uid;
559
560         expiry = get_expiry(&mesg);
561         if (expiry == 0)
562                 return -EINVAL;
563
564         rv = get_int(&mesg, &gids);
565         if (rv || gids < 0 || gids > 8192)
566                 return -EINVAL;
567
568         ug.gi = groups_alloc(gids);
569         if (!ug.gi)
570                 return -ENOMEM;
571
572         for (i = 0 ; i < gids ; i++) {
573                 int gid;
574                 rv = get_int(&mesg, &gid);
575                 err = -EINVAL;
576                 if (rv)
577                         goto out;
578                 GROUP_AT(ug.gi, i) = gid;
579         }
580
581         ugp = unix_gid_lookup(uid);
582         if (ugp) {
583                 struct cache_head *ch;
584                 ug.h.flags = 0;
585                 ug.h.expiry_time = expiry;
586                 ch = sunrpc_cache_update(&unix_gid_cache,
587                                          &ug.h, &ugp->h,
588                                          hash_long(uid, GID_HASHBITS));
589                 if (!ch)
590                         err = -ENOMEM;
591                 else {
592                         err = 0;
593                         cache_put(ch, &unix_gid_cache);
594                 }
595         } else
596                 err = -ENOMEM;
597  out:
598         if (ug.gi)
599                 put_group_info(ug.gi);
600         return err;
601 }
602
603 static int unix_gid_show(struct seq_file *m,
604                          struct cache_detail *cd,
605                          struct cache_head *h)
606 {
607         struct unix_gid *ug;
608         int i;
609         int glen;
610
611         if (h == NULL) {
612                 seq_puts(m, "#uid cnt: gids...\n");
613                 return 0;
614         }
615         ug = container_of(h, struct unix_gid, h);
616         if (test_bit(CACHE_VALID, &h->flags) &&
617             !test_bit(CACHE_NEGATIVE, &h->flags))
618                 glen = ug->gi->ngroups;
619         else
620                 glen = 0;
621
622         seq_printf(m, "%d %d:", ug->uid, glen);
623         for (i = 0; i < glen; i++)
624                 seq_printf(m, " %d", GROUP_AT(ug->gi, i));
625         seq_printf(m, "\n");
626         return 0;
627 }
628
629 struct cache_detail unix_gid_cache = {
630         .owner          = THIS_MODULE,
631         .hash_size      = GID_HASHMAX,
632         .hash_table     = gid_table,
633         .name           = "auth.unix.gid",
634         .cache_put      = unix_gid_put,
635         .cache_request  = unix_gid_request,
636         .cache_parse    = unix_gid_parse,
637         .cache_show     = unix_gid_show,
638         .match          = unix_gid_match,
639         .init           = unix_gid_init,
640         .update         = unix_gid_update,
641         .alloc          = unix_gid_alloc,
642 };
643
644 static struct unix_gid *unix_gid_lookup(uid_t uid)
645 {
646         struct unix_gid ug;
647         struct cache_head *ch;
648
649         ug.uid = uid;
650         ch = sunrpc_cache_lookup(&unix_gid_cache, &ug.h,
651                                  hash_long(uid, GID_HASHBITS));
652         if (ch)
653                 return container_of(ch, struct unix_gid, h);
654         else
655                 return NULL;
656 }
657
658 static int unix_gid_find(uid_t uid, struct group_info **gip,
659                          struct svc_rqst *rqstp)
660 {
661         struct unix_gid *ug = unix_gid_lookup(uid);
662         if (!ug)
663                 return -EAGAIN;
664         switch (cache_check(&unix_gid_cache, &ug->h, &rqstp->rq_chandle)) {
665         case -ENOENT:
666                 *gip = NULL;
667                 return 0;
668         case 0:
669                 *gip = ug->gi;
670                 get_group_info(*gip);
671                 return 0;
672         default:
673                 return -EAGAIN;
674         }
675 }
676
677 int
678 svcauth_unix_set_client(struct svc_rqst *rqstp)
679 {
680         struct sockaddr_in *sin;
681         struct sockaddr_in6 *sin6, sin6_storage;
682         struct ip_map *ipm;
683
684         switch (rqstp->rq_addr.ss_family) {
685         case AF_INET:
686                 sin = svc_addr_in(rqstp);
687                 sin6 = &sin6_storage;
688                 ipv6_addr_set(&sin6->sin6_addr, 0, 0,
689                                 htonl(0x0000FFFF), sin->sin_addr.s_addr);
690                 break;
691         case AF_INET6:
692                 sin6 = svc_addr_in6(rqstp);
693                 break;
694         default:
695                 BUG();
696         }
697
698         rqstp->rq_client = NULL;
699         if (rqstp->rq_proc == 0)
700                 return SVC_OK;
701
702         ipm = ip_map_cached_get(rqstp);
703         if (ipm == NULL)
704                 ipm = ip_map_lookup(rqstp->rq_server->sv_program->pg_class,
705                                     &sin6->sin6_addr);
706
707         if (ipm == NULL)
708                 return SVC_DENIED;
709
710         switch (cache_check(&ip_map_cache, &ipm->h, &rqstp->rq_chandle)) {
711                 default:
712                         BUG();
713                 case -EAGAIN:
714                 case -ETIMEDOUT:
715                         return SVC_DROP;
716                 case -ENOENT:
717                         return SVC_DENIED;
718                 case 0:
719                         rqstp->rq_client = &ipm->m_client->h;
720                         kref_get(&rqstp->rq_client->ref);
721                         ip_map_cached_put(rqstp, ipm);
722                         break;
723         }
724         return SVC_OK;
725 }
726
727 EXPORT_SYMBOL(svcauth_unix_set_client);
728
729 static int
730 svcauth_null_accept(struct svc_rqst *rqstp, __be32 *authp)
731 {
732         struct kvec     *argv = &rqstp->rq_arg.head[0];
733         struct kvec     *resv = &rqstp->rq_res.head[0];
734         struct svc_cred *cred = &rqstp->rq_cred;
735
736         cred->cr_group_info = NULL;
737         rqstp->rq_client = NULL;
738
739         if (argv->iov_len < 3*4)
740                 return SVC_GARBAGE;
741
742         if (svc_getu32(argv) != 0) {
743                 dprintk("svc: bad null cred\n");
744                 *authp = rpc_autherr_badcred;
745                 return SVC_DENIED;
746         }
747         if (svc_getu32(argv) != htonl(RPC_AUTH_NULL) || svc_getu32(argv) != 0) {
748                 dprintk("svc: bad null verf\n");
749                 *authp = rpc_autherr_badverf;
750                 return SVC_DENIED;
751         }
752
753         /* Signal that mapping to nobody uid/gid is required */
754         cred->cr_uid = (uid_t) -1;
755         cred->cr_gid = (gid_t) -1;
756         cred->cr_group_info = groups_alloc(0);
757         if (cred->cr_group_info == NULL)
758                 return SVC_DROP; /* kmalloc failure - client must retry */
759
760         /* Put NULL verifier */
761         svc_putnl(resv, RPC_AUTH_NULL);
762         svc_putnl(resv, 0);
763
764         rqstp->rq_flavor = RPC_AUTH_NULL;
765         return SVC_OK;
766 }
767
768 static int
769 svcauth_null_release(struct svc_rqst *rqstp)
770 {
771         if (rqstp->rq_client)
772                 auth_domain_put(rqstp->rq_client);
773         rqstp->rq_client = NULL;
774         if (rqstp->rq_cred.cr_group_info)
775                 put_group_info(rqstp->rq_cred.cr_group_info);
776         rqstp->rq_cred.cr_group_info = NULL;
777
778         return 0; /* don't drop */
779 }
780
781
782 struct auth_ops svcauth_null = {
783         .name           = "null",
784         .owner          = THIS_MODULE,
785         .flavour        = RPC_AUTH_NULL,
786         .accept         = svcauth_null_accept,
787         .release        = svcauth_null_release,
788         .set_client     = svcauth_unix_set_client,
789 };
790
791
792 static int
793 svcauth_unix_accept(struct svc_rqst *rqstp, __be32 *authp)
794 {
795         struct kvec     *argv = &rqstp->rq_arg.head[0];
796         struct kvec     *resv = &rqstp->rq_res.head[0];
797         struct svc_cred *cred = &rqstp->rq_cred;
798         u32             slen, i;
799         int             len   = argv->iov_len;
800
801         cred->cr_group_info = NULL;
802         rqstp->rq_client = NULL;
803
804         if ((len -= 3*4) < 0)
805                 return SVC_GARBAGE;
806
807         svc_getu32(argv);                       /* length */
808         svc_getu32(argv);                       /* time stamp */
809         slen = XDR_QUADLEN(svc_getnl(argv));    /* machname length */
810         if (slen > 64 || (len -= (slen + 3)*4) < 0)
811                 goto badcred;
812         argv->iov_base = (void*)((__be32*)argv->iov_base + slen);       /* skip machname */
813         argv->iov_len -= slen*4;
814
815         cred->cr_uid = svc_getnl(argv);         /* uid */
816         cred->cr_gid = svc_getnl(argv);         /* gid */
817         slen = svc_getnl(argv);                 /* gids length */
818         if (slen > 16 || (len -= (slen + 2)*4) < 0)
819                 goto badcred;
820         if (unix_gid_find(cred->cr_uid, &cred->cr_group_info, rqstp)
821             == -EAGAIN)
822                 return SVC_DROP;
823         if (cred->cr_group_info == NULL) {
824                 cred->cr_group_info = groups_alloc(slen);
825                 if (cred->cr_group_info == NULL)
826                         return SVC_DROP;
827                 for (i = 0; i < slen; i++)
828                         GROUP_AT(cred->cr_group_info, i) = svc_getnl(argv);
829         } else {
830                 for (i = 0; i < slen ; i++)
831                         svc_getnl(argv);
832         }
833         if (svc_getu32(argv) != htonl(RPC_AUTH_NULL) || svc_getu32(argv) != 0) {
834                 *authp = rpc_autherr_badverf;
835                 return SVC_DENIED;
836         }
837
838         /* Put NULL verifier */
839         svc_putnl(resv, RPC_AUTH_NULL);
840         svc_putnl(resv, 0);
841
842         rqstp->rq_flavor = RPC_AUTH_UNIX;
843         return SVC_OK;
844
845 badcred:
846         *authp = rpc_autherr_badcred;
847         return SVC_DENIED;
848 }
849
850 static int
851 svcauth_unix_release(struct svc_rqst *rqstp)
852 {
853         /* Verifier (such as it is) is already in place.
854          */
855         if (rqstp->rq_client)
856                 auth_domain_put(rqstp->rq_client);
857         rqstp->rq_client = NULL;
858         if (rqstp->rq_cred.cr_group_info)
859                 put_group_info(rqstp->rq_cred.cr_group_info);
860         rqstp->rq_cred.cr_group_info = NULL;
861
862         return 0;
863 }
864
865
866 struct auth_ops svcauth_unix = {
867         .name           = "unix",
868         .owner          = THIS_MODULE,
869         .flavour        = RPC_AUTH_UNIX,
870         .accept         = svcauth_unix_accept,
871         .release        = svcauth_unix_release,
872         .domain_release = svcauth_unix_domain_release,
873         .set_client     = svcauth_unix_set_client,
874 };
875