xref: /linux/net/sunrpc/svcauth_unix.c (revision 4413e16d9d21673bb5048a2e542f1aaa00015c2e)
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 <linux/slab.h>
14 #include <net/sock.h>
15 #include <net/ipv6.h>
16 #include <linux/kernel.h>
17 #include <linux/user_namespace.h>
18 #define RPCDBG_FACILITY	RPCDBG_AUTH
19 
20 #include <linux/sunrpc/clnt.h>
21 
22 #include "netns.h"
23 
24 /*
25  * AUTHUNIX and AUTHNULL credentials are both handled here.
26  * AUTHNULL is treated just like AUTHUNIX except that the uid/gid
27  * are always nobody (-2).  i.e. we do the same IP address checks for
28  * AUTHNULL as for AUTHUNIX, and that is done here.
29  */
30 
31 
32 struct unix_domain {
33 	struct auth_domain	h;
34 	/* other stuff later */
35 };
36 
37 extern struct auth_ops svcauth_null;
38 extern struct auth_ops svcauth_unix;
39 
40 static void svcauth_unix_domain_release(struct auth_domain *dom)
41 {
42 	struct unix_domain *ud = container_of(dom, struct unix_domain, h);
43 
44 	kfree(dom->name);
45 	kfree(ud);
46 }
47 
48 struct auth_domain *unix_domain_find(char *name)
49 {
50 	struct auth_domain *rv;
51 	struct unix_domain *new = NULL;
52 
53 	rv = auth_domain_lookup(name, NULL);
54 	while(1) {
55 		if (rv) {
56 			if (new && rv != &new->h)
57 				svcauth_unix_domain_release(&new->h);
58 
59 			if (rv->flavour != &svcauth_unix) {
60 				auth_domain_put(rv);
61 				return NULL;
62 			}
63 			return rv;
64 		}
65 
66 		new = kmalloc(sizeof(*new), GFP_KERNEL);
67 		if (new == NULL)
68 			return NULL;
69 		kref_init(&new->h.ref);
70 		new->h.name = kstrdup(name, GFP_KERNEL);
71 		if (new->h.name == NULL) {
72 			kfree(new);
73 			return NULL;
74 		}
75 		new->h.flavour = &svcauth_unix;
76 		rv = auth_domain_lookup(name, &new->h);
77 	}
78 }
79 EXPORT_SYMBOL_GPL(unix_domain_find);
80 
81 
82 /**************************************************
83  * cache for IP address to unix_domain
84  * as needed by AUTH_UNIX
85  */
86 #define	IP_HASHBITS	8
87 #define	IP_HASHMAX	(1<<IP_HASHBITS)
88 
89 struct ip_map {
90 	struct cache_head	h;
91 	char			m_class[8]; /* e.g. "nfsd" */
92 	struct in6_addr		m_addr;
93 	struct unix_domain	*m_client;
94 };
95 
96 static void ip_map_put(struct kref *kref)
97 {
98 	struct cache_head *item = container_of(kref, struct cache_head, ref);
99 	struct ip_map *im = container_of(item, struct ip_map,h);
100 
101 	if (test_bit(CACHE_VALID, &item->flags) &&
102 	    !test_bit(CACHE_NEGATIVE, &item->flags))
103 		auth_domain_put(&im->m_client->h);
104 	kfree(im);
105 }
106 
107 static inline int hash_ip6(const struct in6_addr *ip)
108 {
109 	return hash_32(ipv6_addr_hash(ip), IP_HASHBITS);
110 }
111 static int ip_map_match(struct cache_head *corig, struct cache_head *cnew)
112 {
113 	struct ip_map *orig = container_of(corig, struct ip_map, h);
114 	struct ip_map *new = container_of(cnew, struct ip_map, h);
115 	return strcmp(orig->m_class, new->m_class) == 0 &&
116 	       ipv6_addr_equal(&orig->m_addr, &new->m_addr);
117 }
118 static void ip_map_init(struct cache_head *cnew, struct cache_head *citem)
119 {
120 	struct ip_map *new = container_of(cnew, struct ip_map, h);
121 	struct ip_map *item = container_of(citem, struct ip_map, h);
122 
123 	strcpy(new->m_class, item->m_class);
124 	new->m_addr = item->m_addr;
125 }
126 static void update(struct cache_head *cnew, struct cache_head *citem)
127 {
128 	struct ip_map *new = container_of(cnew, struct ip_map, h);
129 	struct ip_map *item = container_of(citem, struct ip_map, h);
130 
131 	kref_get(&item->m_client->h.ref);
132 	new->m_client = item->m_client;
133 }
134 static struct cache_head *ip_map_alloc(void)
135 {
136 	struct ip_map *i = kmalloc(sizeof(*i), GFP_KERNEL);
137 	if (i)
138 		return &i->h;
139 	else
140 		return NULL;
141 }
142 
143 static void ip_map_request(struct cache_detail *cd,
144 				  struct cache_head *h,
145 				  char **bpp, int *blen)
146 {
147 	char text_addr[40];
148 	struct ip_map *im = container_of(h, struct ip_map, h);
149 
150 	if (ipv6_addr_v4mapped(&(im->m_addr))) {
151 		snprintf(text_addr, 20, "%pI4", &im->m_addr.s6_addr32[3]);
152 	} else {
153 		snprintf(text_addr, 40, "%pI6", &im->m_addr);
154 	}
155 	qword_add(bpp, blen, im->m_class);
156 	qword_add(bpp, blen, text_addr);
157 	(*bpp)[-1] = '\n';
158 }
159 
160 static int ip_map_upcall(struct cache_detail *cd, struct cache_head *h)
161 {
162 	return sunrpc_cache_pipe_upcall(cd, h, ip_map_request);
163 }
164 
165 static struct ip_map *__ip_map_lookup(struct cache_detail *cd, char *class, struct in6_addr *addr);
166 static int __ip_map_update(struct cache_detail *cd, struct ip_map *ipm, struct unix_domain *udom, time_t expiry);
167 
168 static int ip_map_parse(struct cache_detail *cd,
169 			  char *mesg, int mlen)
170 {
171 	/* class ipaddress [domainname] */
172 	/* should be safe just to use the start of the input buffer
173 	 * for scratch: */
174 	char *buf = mesg;
175 	int len;
176 	char class[8];
177 	union {
178 		struct sockaddr		sa;
179 		struct sockaddr_in	s4;
180 		struct sockaddr_in6	s6;
181 	} address;
182 	struct sockaddr_in6 sin6;
183 	int err;
184 
185 	struct ip_map *ipmp;
186 	struct auth_domain *dom;
187 	time_t expiry;
188 
189 	if (mesg[mlen-1] != '\n')
190 		return -EINVAL;
191 	mesg[mlen-1] = 0;
192 
193 	/* class */
194 	len = qword_get(&mesg, class, sizeof(class));
195 	if (len <= 0) return -EINVAL;
196 
197 	/* ip address */
198 	len = qword_get(&mesg, buf, mlen);
199 	if (len <= 0) return -EINVAL;
200 
201 	if (rpc_pton(cd->net, buf, len, &address.sa, sizeof(address)) == 0)
202 		return -EINVAL;
203 	switch (address.sa.sa_family) {
204 	case AF_INET:
205 		/* Form a mapped IPv4 address in sin6 */
206 		sin6.sin6_family = AF_INET6;
207 		ipv6_addr_set_v4mapped(address.s4.sin_addr.s_addr,
208 				&sin6.sin6_addr);
209 		break;
210 #if IS_ENABLED(CONFIG_IPV6)
211 	case AF_INET6:
212 		memcpy(&sin6, &address.s6, sizeof(sin6));
213 		break;
214 #endif
215 	default:
216 		return -EINVAL;
217 	}
218 
219 	expiry = get_expiry(&mesg);
220 	if (expiry ==0)
221 		return -EINVAL;
222 
223 	/* domainname, or empty for NEGATIVE */
224 	len = qword_get(&mesg, buf, mlen);
225 	if (len < 0) return -EINVAL;
226 
227 	if (len) {
228 		dom = unix_domain_find(buf);
229 		if (dom == NULL)
230 			return -ENOENT;
231 	} else
232 		dom = NULL;
233 
234 	/* IPv6 scope IDs are ignored for now */
235 	ipmp = __ip_map_lookup(cd, class, &sin6.sin6_addr);
236 	if (ipmp) {
237 		err = __ip_map_update(cd, ipmp,
238 			     container_of(dom, struct unix_domain, h),
239 			     expiry);
240 	} else
241 		err = -ENOMEM;
242 
243 	if (dom)
244 		auth_domain_put(dom);
245 
246 	cache_flush();
247 	return err;
248 }
249 
250 static int ip_map_show(struct seq_file *m,
251 		       struct cache_detail *cd,
252 		       struct cache_head *h)
253 {
254 	struct ip_map *im;
255 	struct in6_addr addr;
256 	char *dom = "-no-domain-";
257 
258 	if (h == NULL) {
259 		seq_puts(m, "#class IP domain\n");
260 		return 0;
261 	}
262 	im = container_of(h, struct ip_map, h);
263 	/* class addr domain */
264 	addr = im->m_addr;
265 
266 	if (test_bit(CACHE_VALID, &h->flags) &&
267 	    !test_bit(CACHE_NEGATIVE, &h->flags))
268 		dom = im->m_client->h.name;
269 
270 	if (ipv6_addr_v4mapped(&addr)) {
271 		seq_printf(m, "%s %pI4 %s\n",
272 			im->m_class, &addr.s6_addr32[3], dom);
273 	} else {
274 		seq_printf(m, "%s %pI6 %s\n", im->m_class, &addr, dom);
275 	}
276 	return 0;
277 }
278 
279 
280 static struct ip_map *__ip_map_lookup(struct cache_detail *cd, char *class,
281 		struct in6_addr *addr)
282 {
283 	struct ip_map ip;
284 	struct cache_head *ch;
285 
286 	strcpy(ip.m_class, class);
287 	ip.m_addr = *addr;
288 	ch = sunrpc_cache_lookup(cd, &ip.h,
289 				 hash_str(class, IP_HASHBITS) ^
290 				 hash_ip6(addr));
291 
292 	if (ch)
293 		return container_of(ch, struct ip_map, h);
294 	else
295 		return NULL;
296 }
297 
298 static inline struct ip_map *ip_map_lookup(struct net *net, char *class,
299 		struct in6_addr *addr)
300 {
301 	struct sunrpc_net *sn;
302 
303 	sn = net_generic(net, sunrpc_net_id);
304 	return __ip_map_lookup(sn->ip_map_cache, class, addr);
305 }
306 
307 static int __ip_map_update(struct cache_detail *cd, struct ip_map *ipm,
308 		struct unix_domain *udom, time_t expiry)
309 {
310 	struct ip_map ip;
311 	struct cache_head *ch;
312 
313 	ip.m_client = udom;
314 	ip.h.flags = 0;
315 	if (!udom)
316 		set_bit(CACHE_NEGATIVE, &ip.h.flags);
317 	ip.h.expiry_time = expiry;
318 	ch = sunrpc_cache_update(cd, &ip.h, &ipm->h,
319 				 hash_str(ipm->m_class, IP_HASHBITS) ^
320 				 hash_ip6(&ipm->m_addr));
321 	if (!ch)
322 		return -ENOMEM;
323 	cache_put(ch, cd);
324 	return 0;
325 }
326 
327 static inline int ip_map_update(struct net *net, struct ip_map *ipm,
328 		struct unix_domain *udom, time_t expiry)
329 {
330 	struct sunrpc_net *sn;
331 
332 	sn = net_generic(net, sunrpc_net_id);
333 	return __ip_map_update(sn->ip_map_cache, ipm, udom, expiry);
334 }
335 
336 void svcauth_unix_purge(struct net *net)
337 {
338 	struct sunrpc_net *sn;
339 
340 	sn = net_generic(net, sunrpc_net_id);
341 	cache_purge(sn->ip_map_cache);
342 }
343 EXPORT_SYMBOL_GPL(svcauth_unix_purge);
344 
345 static inline struct ip_map *
346 ip_map_cached_get(struct svc_xprt *xprt)
347 {
348 	struct ip_map *ipm = NULL;
349 	struct sunrpc_net *sn;
350 
351 	if (test_bit(XPT_CACHE_AUTH, &xprt->xpt_flags)) {
352 		spin_lock(&xprt->xpt_lock);
353 		ipm = xprt->xpt_auth_cache;
354 		if (ipm != NULL) {
355 			if (!cache_valid(&ipm->h)) {
356 				/*
357 				 * The entry has been invalidated since it was
358 				 * remembered, e.g. by a second mount from the
359 				 * same IP address.
360 				 */
361 				sn = net_generic(xprt->xpt_net, sunrpc_net_id);
362 				xprt->xpt_auth_cache = NULL;
363 				spin_unlock(&xprt->xpt_lock);
364 				cache_put(&ipm->h, sn->ip_map_cache);
365 				return NULL;
366 			}
367 			cache_get(&ipm->h);
368 		}
369 		spin_unlock(&xprt->xpt_lock);
370 	}
371 	return ipm;
372 }
373 
374 static inline void
375 ip_map_cached_put(struct svc_xprt *xprt, struct ip_map *ipm)
376 {
377 	if (test_bit(XPT_CACHE_AUTH, &xprt->xpt_flags)) {
378 		spin_lock(&xprt->xpt_lock);
379 		if (xprt->xpt_auth_cache == NULL) {
380 			/* newly cached, keep the reference */
381 			xprt->xpt_auth_cache = ipm;
382 			ipm = NULL;
383 		}
384 		spin_unlock(&xprt->xpt_lock);
385 	}
386 	if (ipm) {
387 		struct sunrpc_net *sn;
388 
389 		sn = net_generic(xprt->xpt_net, sunrpc_net_id);
390 		cache_put(&ipm->h, sn->ip_map_cache);
391 	}
392 }
393 
394 void
395 svcauth_unix_info_release(struct svc_xprt *xpt)
396 {
397 	struct ip_map *ipm;
398 
399 	ipm = xpt->xpt_auth_cache;
400 	if (ipm != NULL) {
401 		struct sunrpc_net *sn;
402 
403 		sn = net_generic(xpt->xpt_net, sunrpc_net_id);
404 		cache_put(&ipm->h, sn->ip_map_cache);
405 	}
406 }
407 
408 /****************************************************************************
409  * auth.unix.gid cache
410  * simple cache to map a UID to a list of GIDs
411  * because AUTH_UNIX aka AUTH_SYS has a max of 16
412  */
413 #define	GID_HASHBITS	8
414 #define	GID_HASHMAX	(1<<GID_HASHBITS)
415 
416 struct unix_gid {
417 	struct cache_head	h;
418 	uid_t			uid;
419 	struct group_info	*gi;
420 };
421 
422 static void unix_gid_put(struct kref *kref)
423 {
424 	struct cache_head *item = container_of(kref, struct cache_head, ref);
425 	struct unix_gid *ug = container_of(item, struct unix_gid, h);
426 	if (test_bit(CACHE_VALID, &item->flags) &&
427 	    !test_bit(CACHE_NEGATIVE, &item->flags))
428 		put_group_info(ug->gi);
429 	kfree(ug);
430 }
431 
432 static int unix_gid_match(struct cache_head *corig, struct cache_head *cnew)
433 {
434 	struct unix_gid *orig = container_of(corig, struct unix_gid, h);
435 	struct unix_gid *new = container_of(cnew, struct unix_gid, h);
436 	return orig->uid == new->uid;
437 }
438 static void unix_gid_init(struct cache_head *cnew, struct cache_head *citem)
439 {
440 	struct unix_gid *new = container_of(cnew, struct unix_gid, h);
441 	struct unix_gid *item = container_of(citem, struct unix_gid, h);
442 	new->uid = item->uid;
443 }
444 static void unix_gid_update(struct cache_head *cnew, struct cache_head *citem)
445 {
446 	struct unix_gid *new = container_of(cnew, struct unix_gid, h);
447 	struct unix_gid *item = container_of(citem, struct unix_gid, h);
448 
449 	get_group_info(item->gi);
450 	new->gi = item->gi;
451 }
452 static struct cache_head *unix_gid_alloc(void)
453 {
454 	struct unix_gid *g = kmalloc(sizeof(*g), GFP_KERNEL);
455 	if (g)
456 		return &g->h;
457 	else
458 		return NULL;
459 }
460 
461 static void unix_gid_request(struct cache_detail *cd,
462 			     struct cache_head *h,
463 			     char **bpp, int *blen)
464 {
465 	char tuid[20];
466 	struct unix_gid *ug = container_of(h, struct unix_gid, h);
467 
468 	snprintf(tuid, 20, "%u", ug->uid);
469 	qword_add(bpp, blen, tuid);
470 	(*bpp)[-1] = '\n';
471 }
472 
473 static int unix_gid_upcall(struct cache_detail *cd, struct cache_head *h)
474 {
475 	return sunrpc_cache_pipe_upcall(cd, h, unix_gid_request);
476 }
477 
478 static struct unix_gid *unix_gid_lookup(struct cache_detail *cd, uid_t uid);
479 
480 static int unix_gid_parse(struct cache_detail *cd,
481 			char *mesg, int mlen)
482 {
483 	/* uid expiry Ngid gid0 gid1 ... gidN-1 */
484 	int uid;
485 	int gids;
486 	int rv;
487 	int i;
488 	int err;
489 	time_t expiry;
490 	struct unix_gid ug, *ugp;
491 
492 	if (mesg[mlen - 1] != '\n')
493 		return -EINVAL;
494 	mesg[mlen-1] = 0;
495 
496 	rv = get_int(&mesg, &uid);
497 	if (rv)
498 		return -EINVAL;
499 	ug.uid = uid;
500 
501 	expiry = get_expiry(&mesg);
502 	if (expiry == 0)
503 		return -EINVAL;
504 
505 	rv = get_int(&mesg, &gids);
506 	if (rv || gids < 0 || gids > 8192)
507 		return -EINVAL;
508 
509 	ug.gi = groups_alloc(gids);
510 	if (!ug.gi)
511 		return -ENOMEM;
512 
513 	for (i = 0 ; i < gids ; i++) {
514 		int gid;
515 		kgid_t kgid;
516 		rv = get_int(&mesg, &gid);
517 		err = -EINVAL;
518 		if (rv)
519 			goto out;
520 		kgid = make_kgid(&init_user_ns, gid);
521 		if (!gid_valid(kgid))
522 			goto out;
523 		GROUP_AT(ug.gi, i) = kgid;
524 	}
525 
526 	ugp = unix_gid_lookup(cd, uid);
527 	if (ugp) {
528 		struct cache_head *ch;
529 		ug.h.flags = 0;
530 		ug.h.expiry_time = expiry;
531 		ch = sunrpc_cache_update(cd,
532 					 &ug.h, &ugp->h,
533 					 hash_long(uid, GID_HASHBITS));
534 		if (!ch)
535 			err = -ENOMEM;
536 		else {
537 			err = 0;
538 			cache_put(ch, cd);
539 		}
540 	} else
541 		err = -ENOMEM;
542  out:
543 	if (ug.gi)
544 		put_group_info(ug.gi);
545 	return err;
546 }
547 
548 static int unix_gid_show(struct seq_file *m,
549 			 struct cache_detail *cd,
550 			 struct cache_head *h)
551 {
552 	struct user_namespace *user_ns = current_user_ns();
553 	struct unix_gid *ug;
554 	int i;
555 	int glen;
556 
557 	if (h == NULL) {
558 		seq_puts(m, "#uid cnt: gids...\n");
559 		return 0;
560 	}
561 	ug = container_of(h, struct unix_gid, h);
562 	if (test_bit(CACHE_VALID, &h->flags) &&
563 	    !test_bit(CACHE_NEGATIVE, &h->flags))
564 		glen = ug->gi->ngroups;
565 	else
566 		glen = 0;
567 
568 	seq_printf(m, "%u %d:", ug->uid, glen);
569 	for (i = 0; i < glen; i++)
570 		seq_printf(m, " %d", from_kgid_munged(user_ns, GROUP_AT(ug->gi, i)));
571 	seq_printf(m, "\n");
572 	return 0;
573 }
574 
575 static struct cache_detail unix_gid_cache_template = {
576 	.owner		= THIS_MODULE,
577 	.hash_size	= GID_HASHMAX,
578 	.name		= "auth.unix.gid",
579 	.cache_put	= unix_gid_put,
580 	.cache_upcall	= unix_gid_upcall,
581 	.cache_parse	= unix_gid_parse,
582 	.cache_show	= unix_gid_show,
583 	.match		= unix_gid_match,
584 	.init		= unix_gid_init,
585 	.update		= unix_gid_update,
586 	.alloc		= unix_gid_alloc,
587 };
588 
589 int unix_gid_cache_create(struct net *net)
590 {
591 	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
592 	struct cache_detail *cd;
593 	int err;
594 
595 	cd = cache_create_net(&unix_gid_cache_template, net);
596 	if (IS_ERR(cd))
597 		return PTR_ERR(cd);
598 	err = cache_register_net(cd, net);
599 	if (err) {
600 		cache_destroy_net(cd, net);
601 		return err;
602 	}
603 	sn->unix_gid_cache = cd;
604 	return 0;
605 }
606 
607 void unix_gid_cache_destroy(struct net *net)
608 {
609 	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
610 	struct cache_detail *cd = sn->unix_gid_cache;
611 
612 	sn->unix_gid_cache = NULL;
613 	cache_purge(cd);
614 	cache_unregister_net(cd, net);
615 	cache_destroy_net(cd, net);
616 }
617 
618 static struct unix_gid *unix_gid_lookup(struct cache_detail *cd, uid_t uid)
619 {
620 	struct unix_gid ug;
621 	struct cache_head *ch;
622 
623 	ug.uid = uid;
624 	ch = sunrpc_cache_lookup(cd, &ug.h, hash_long(uid, GID_HASHBITS));
625 	if (ch)
626 		return container_of(ch, struct unix_gid, h);
627 	else
628 		return NULL;
629 }
630 
631 static struct group_info *unix_gid_find(uid_t uid, struct svc_rqst *rqstp)
632 {
633 	struct unix_gid *ug;
634 	struct group_info *gi;
635 	int ret;
636 	struct sunrpc_net *sn = net_generic(rqstp->rq_xprt->xpt_net,
637 					    sunrpc_net_id);
638 
639 	ug = unix_gid_lookup(sn->unix_gid_cache, uid);
640 	if (!ug)
641 		return ERR_PTR(-EAGAIN);
642 	ret = cache_check(sn->unix_gid_cache, &ug->h, &rqstp->rq_chandle);
643 	switch (ret) {
644 	case -ENOENT:
645 		return ERR_PTR(-ENOENT);
646 	case -ETIMEDOUT:
647 		return ERR_PTR(-ESHUTDOWN);
648 	case 0:
649 		gi = get_group_info(ug->gi);
650 		cache_put(&ug->h, sn->unix_gid_cache);
651 		return gi;
652 	default:
653 		return ERR_PTR(-EAGAIN);
654 	}
655 }
656 
657 int
658 svcauth_unix_set_client(struct svc_rqst *rqstp)
659 {
660 	struct sockaddr_in *sin;
661 	struct sockaddr_in6 *sin6, sin6_storage;
662 	struct ip_map *ipm;
663 	struct group_info *gi;
664 	struct svc_cred *cred = &rqstp->rq_cred;
665 	struct svc_xprt *xprt = rqstp->rq_xprt;
666 	struct net *net = xprt->xpt_net;
667 	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
668 
669 	switch (rqstp->rq_addr.ss_family) {
670 	case AF_INET:
671 		sin = svc_addr_in(rqstp);
672 		sin6 = &sin6_storage;
673 		ipv6_addr_set_v4mapped(sin->sin_addr.s_addr, &sin6->sin6_addr);
674 		break;
675 	case AF_INET6:
676 		sin6 = svc_addr_in6(rqstp);
677 		break;
678 	default:
679 		BUG();
680 	}
681 
682 	rqstp->rq_client = NULL;
683 	if (rqstp->rq_proc == 0)
684 		return SVC_OK;
685 
686 	ipm = ip_map_cached_get(xprt);
687 	if (ipm == NULL)
688 		ipm = __ip_map_lookup(sn->ip_map_cache, rqstp->rq_server->sv_program->pg_class,
689 				    &sin6->sin6_addr);
690 
691 	if (ipm == NULL)
692 		return SVC_DENIED;
693 
694 	switch (cache_check(sn->ip_map_cache, &ipm->h, &rqstp->rq_chandle)) {
695 		default:
696 			BUG();
697 		case -ETIMEDOUT:
698 			return SVC_CLOSE;
699 		case -EAGAIN:
700 			return SVC_DROP;
701 		case -ENOENT:
702 			return SVC_DENIED;
703 		case 0:
704 			rqstp->rq_client = &ipm->m_client->h;
705 			kref_get(&rqstp->rq_client->ref);
706 			ip_map_cached_put(xprt, ipm);
707 			break;
708 	}
709 
710 	gi = unix_gid_find(cred->cr_uid, rqstp);
711 	switch (PTR_ERR(gi)) {
712 	case -EAGAIN:
713 		return SVC_DROP;
714 	case -ESHUTDOWN:
715 		return SVC_CLOSE;
716 	case -ENOENT:
717 		break;
718 	default:
719 		put_group_info(cred->cr_group_info);
720 		cred->cr_group_info = gi;
721 	}
722 	return SVC_OK;
723 }
724 
725 EXPORT_SYMBOL_GPL(svcauth_unix_set_client);
726 
727 static int
728 svcauth_null_accept(struct svc_rqst *rqstp, __be32 *authp)
729 {
730 	struct kvec	*argv = &rqstp->rq_arg.head[0];
731 	struct kvec	*resv = &rqstp->rq_res.head[0];
732 	struct svc_cred	*cred = &rqstp->rq_cred;
733 
734 	cred->cr_group_info = NULL;
735 	cred->cr_principal = NULL;
736 	rqstp->rq_client = NULL;
737 
738 	if (argv->iov_len < 3*4)
739 		return SVC_GARBAGE;
740 
741 	if (svc_getu32(argv) != 0) {
742 		dprintk("svc: bad null cred\n");
743 		*authp = rpc_autherr_badcred;
744 		return SVC_DENIED;
745 	}
746 	if (svc_getu32(argv) != htonl(RPC_AUTH_NULL) || svc_getu32(argv) != 0) {
747 		dprintk("svc: bad null verf\n");
748 		*authp = rpc_autherr_badverf;
749 		return SVC_DENIED;
750 	}
751 
752 	/* Signal that mapping to nobody uid/gid is required */
753 	cred->cr_uid = (uid_t) -1;
754 	cred->cr_gid = (gid_t) -1;
755 	cred->cr_group_info = groups_alloc(0);
756 	if (cred->cr_group_info == NULL)
757 		return SVC_CLOSE; /* kmalloc failure - client must retry */
758 
759 	/* Put NULL verifier */
760 	svc_putnl(resv, RPC_AUTH_NULL);
761 	svc_putnl(resv, 0);
762 
763 	rqstp->rq_cred.cr_flavor = RPC_AUTH_NULL;
764 	return SVC_OK;
765 }
766 
767 static int
768 svcauth_null_release(struct svc_rqst *rqstp)
769 {
770 	if (rqstp->rq_client)
771 		auth_domain_put(rqstp->rq_client);
772 	rqstp->rq_client = NULL;
773 	if (rqstp->rq_cred.cr_group_info)
774 		put_group_info(rqstp->rq_cred.cr_group_info);
775 	rqstp->rq_cred.cr_group_info = NULL;
776 
777 	return 0; /* don't drop */
778 }
779 
780 
781 struct auth_ops svcauth_null = {
782 	.name		= "null",
783 	.owner		= THIS_MODULE,
784 	.flavour	= RPC_AUTH_NULL,
785 	.accept 	= svcauth_null_accept,
786 	.release	= svcauth_null_release,
787 	.set_client	= svcauth_unix_set_client,
788 };
789 
790 
791 static int
792 svcauth_unix_accept(struct svc_rqst *rqstp, __be32 *authp)
793 {
794 	struct kvec	*argv = &rqstp->rq_arg.head[0];
795 	struct kvec	*resv = &rqstp->rq_res.head[0];
796 	struct svc_cred	*cred = &rqstp->rq_cred;
797 	u32		slen, i;
798 	int		len   = argv->iov_len;
799 
800 	cred->cr_group_info = NULL;
801 	cred->cr_principal = 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 	cred->cr_group_info = groups_alloc(slen);
821 	if (cred->cr_group_info == NULL)
822 		return SVC_CLOSE;
823 	for (i = 0; i < slen; i++) {
824 		kgid_t kgid = make_kgid(&init_user_ns, svc_getnl(argv));
825 		if (!gid_valid(kgid))
826 			goto badcred;
827 		GROUP_AT(cred->cr_group_info, i) = kgid;
828 	}
829 	if (svc_getu32(argv) != htonl(RPC_AUTH_NULL) || svc_getu32(argv) != 0) {
830 		*authp = rpc_autherr_badverf;
831 		return SVC_DENIED;
832 	}
833 
834 	/* Put NULL verifier */
835 	svc_putnl(resv, RPC_AUTH_NULL);
836 	svc_putnl(resv, 0);
837 
838 	rqstp->rq_cred.cr_flavor = RPC_AUTH_UNIX;
839 	return SVC_OK;
840 
841 badcred:
842 	*authp = rpc_autherr_badcred;
843 	return SVC_DENIED;
844 }
845 
846 static int
847 svcauth_unix_release(struct svc_rqst *rqstp)
848 {
849 	/* Verifier (such as it is) is already in place.
850 	 */
851 	if (rqstp->rq_client)
852 		auth_domain_put(rqstp->rq_client);
853 	rqstp->rq_client = NULL;
854 	if (rqstp->rq_cred.cr_group_info)
855 		put_group_info(rqstp->rq_cred.cr_group_info);
856 	rqstp->rq_cred.cr_group_info = NULL;
857 
858 	return 0;
859 }
860 
861 
862 struct auth_ops svcauth_unix = {
863 	.name		= "unix",
864 	.owner		= THIS_MODULE,
865 	.flavour	= RPC_AUTH_UNIX,
866 	.accept 	= svcauth_unix_accept,
867 	.release	= svcauth_unix_release,
868 	.domain_release	= svcauth_unix_domain_release,
869 	.set_client	= svcauth_unix_set_client,
870 };
871 
872 static struct cache_detail ip_map_cache_template = {
873 	.owner		= THIS_MODULE,
874 	.hash_size	= IP_HASHMAX,
875 	.name		= "auth.unix.ip",
876 	.cache_put	= ip_map_put,
877 	.cache_upcall	= ip_map_upcall,
878 	.cache_parse	= ip_map_parse,
879 	.cache_show	= ip_map_show,
880 	.match		= ip_map_match,
881 	.init		= ip_map_init,
882 	.update		= update,
883 	.alloc		= ip_map_alloc,
884 };
885 
886 int ip_map_cache_create(struct net *net)
887 {
888 	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
889 	struct cache_detail *cd;
890 	int err;
891 
892 	cd = cache_create_net(&ip_map_cache_template, net);
893 	if (IS_ERR(cd))
894 		return PTR_ERR(cd);
895 	err = cache_register_net(cd, net);
896 	if (err) {
897 		cache_destroy_net(cd, net);
898 		return err;
899 	}
900 	sn->ip_map_cache = cd;
901 	return 0;
902 }
903 
904 void ip_map_cache_destroy(struct net *net)
905 {
906 	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
907 	struct cache_detail *cd = sn->ip_map_cache;
908 
909 	sn->ip_map_cache = NULL;
910 	cache_purge(cd);
911 	cache_unregister_net(cd, net);
912 	cache_destroy_net(cd, net);
913 }
914