xref: /openbmc/linux/net/sunrpc/svcauth_unix.c (revision 4e174665)
1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/types.h>
3 #include <linux/sched.h>
4 #include <linux/module.h>
5 #include <linux/sunrpc/types.h>
6 #include <linux/sunrpc/xdr.h>
7 #include <linux/sunrpc/svcsock.h>
8 #include <linux/sunrpc/svcauth.h>
9 #include <linux/sunrpc/gss_api.h>
10 #include <linux/sunrpc/addr.h>
11 #include <linux/err.h>
12 #include <linux/seq_file.h>
13 #include <linux/hash.h>
14 #include <linux/string.h>
15 #include <linux/slab.h>
16 #include <net/sock.h>
17 #include <net/ipv6.h>
18 #include <linux/kernel.h>
19 #include <linux/user_namespace.h>
20 #define RPCDBG_FACILITY	RPCDBG_AUTH
21 
22 
23 #include "netns.h"
24 
25 /*
26  * AUTHUNIX and AUTHNULL credentials are both handled here.
27  * AUTHNULL is treated just like AUTHUNIX except that the uid/gid
28  * are always nobody (-2).  i.e. we do the same IP address checks for
29  * AUTHNULL as for AUTHUNIX, and that is done here.
30  */
31 
32 
33 struct unix_domain {
34 	struct auth_domain	h;
35 	/* other stuff later */
36 };
37 
38 extern struct auth_ops svcauth_null;
39 extern struct auth_ops svcauth_unix;
40 extern struct auth_ops svcauth_tls;
41 
42 static void svcauth_unix_domain_release_rcu(struct rcu_head *head)
43 {
44 	struct auth_domain *dom = container_of(head, struct auth_domain, rcu_head);
45 	struct unix_domain *ud = container_of(dom, struct unix_domain, h);
46 
47 	kfree(dom->name);
48 	kfree(ud);
49 }
50 
51 static void svcauth_unix_domain_release(struct auth_domain *dom)
52 {
53 	call_rcu(&dom->rcu_head, svcauth_unix_domain_release_rcu);
54 }
55 
56 struct auth_domain *unix_domain_find(char *name)
57 {
58 	struct auth_domain *rv;
59 	struct unix_domain *new = NULL;
60 
61 	rv = auth_domain_find(name);
62 	while(1) {
63 		if (rv) {
64 			if (new && rv != &new->h)
65 				svcauth_unix_domain_release(&new->h);
66 
67 			if (rv->flavour != &svcauth_unix) {
68 				auth_domain_put(rv);
69 				return NULL;
70 			}
71 			return rv;
72 		}
73 
74 		new = kmalloc(sizeof(*new), GFP_KERNEL);
75 		if (new == NULL)
76 			return NULL;
77 		kref_init(&new->h.ref);
78 		new->h.name = kstrdup(name, GFP_KERNEL);
79 		if (new->h.name == NULL) {
80 			kfree(new);
81 			return NULL;
82 		}
83 		new->h.flavour = &svcauth_unix;
84 		rv = auth_domain_lookup(name, &new->h);
85 	}
86 }
87 EXPORT_SYMBOL_GPL(unix_domain_find);
88 
89 
90 /**************************************************
91  * cache for IP address to unix_domain
92  * as needed by AUTH_UNIX
93  */
94 #define	IP_HASHBITS	8
95 #define	IP_HASHMAX	(1<<IP_HASHBITS)
96 
97 struct ip_map {
98 	struct cache_head	h;
99 	char			m_class[8]; /* e.g. "nfsd" */
100 	struct in6_addr		m_addr;
101 	struct unix_domain	*m_client;
102 	struct rcu_head		m_rcu;
103 };
104 
105 static void ip_map_put(struct kref *kref)
106 {
107 	struct cache_head *item = container_of(kref, struct cache_head, ref);
108 	struct ip_map *im = container_of(item, struct ip_map,h);
109 
110 	if (test_bit(CACHE_VALID, &item->flags) &&
111 	    !test_bit(CACHE_NEGATIVE, &item->flags))
112 		auth_domain_put(&im->m_client->h);
113 	kfree_rcu(im, m_rcu);
114 }
115 
116 static inline int hash_ip6(const struct in6_addr *ip)
117 {
118 	return hash_32(ipv6_addr_hash(ip), IP_HASHBITS);
119 }
120 static int ip_map_match(struct cache_head *corig, struct cache_head *cnew)
121 {
122 	struct ip_map *orig = container_of(corig, struct ip_map, h);
123 	struct ip_map *new = container_of(cnew, struct ip_map, h);
124 	return strcmp(orig->m_class, new->m_class) == 0 &&
125 	       ipv6_addr_equal(&orig->m_addr, &new->m_addr);
126 }
127 static void ip_map_init(struct cache_head *cnew, struct cache_head *citem)
128 {
129 	struct ip_map *new = container_of(cnew, struct ip_map, h);
130 	struct ip_map *item = container_of(citem, struct ip_map, h);
131 
132 	strcpy(new->m_class, item->m_class);
133 	new->m_addr = item->m_addr;
134 }
135 static void update(struct cache_head *cnew, struct cache_head *citem)
136 {
137 	struct ip_map *new = container_of(cnew, struct ip_map, h);
138 	struct ip_map *item = container_of(citem, struct ip_map, h);
139 
140 	kref_get(&item->m_client->h.ref);
141 	new->m_client = item->m_client;
142 }
143 static struct cache_head *ip_map_alloc(void)
144 {
145 	struct ip_map *i = kmalloc(sizeof(*i), GFP_KERNEL);
146 	if (i)
147 		return &i->h;
148 	else
149 		return NULL;
150 }
151 
152 static int ip_map_upcall(struct cache_detail *cd, struct cache_head *h)
153 {
154 	return sunrpc_cache_pipe_upcall(cd, h);
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, "%pI4", &im->m_addr.s6_addr32[3]);
166 	} else {
167 		snprintf(text_addr, 40, "%pI6", &im->m_addr);
168 	}
169 	qword_add(bpp, blen, im->m_class);
170 	qword_add(bpp, blen, text_addr);
171 	(*bpp)[-1] = '\n';
172 }
173 
174 static struct ip_map *__ip_map_lookup(struct cache_detail *cd, char *class, struct in6_addr *addr);
175 static int __ip_map_update(struct cache_detail *cd, struct ip_map *ipm, struct unix_domain *udom, time64_t expiry);
176 
177 static int ip_map_parse(struct cache_detail *cd,
178 			  char *mesg, int mlen)
179 {
180 	/* class ipaddress [domainname] */
181 	/* should be safe just to use the start of the input buffer
182 	 * for scratch: */
183 	char *buf = mesg;
184 	int len;
185 	char class[8];
186 	union {
187 		struct sockaddr		sa;
188 		struct sockaddr_in	s4;
189 		struct sockaddr_in6	s6;
190 	} address;
191 	struct sockaddr_in6 sin6;
192 	int err;
193 
194 	struct ip_map *ipmp;
195 	struct auth_domain *dom;
196 	time64_t expiry;
197 
198 	if (mesg[mlen-1] != '\n')
199 		return -EINVAL;
200 	mesg[mlen-1] = 0;
201 
202 	/* class */
203 	len = qword_get(&mesg, class, sizeof(class));
204 	if (len <= 0) return -EINVAL;
205 
206 	/* ip address */
207 	len = qword_get(&mesg, buf, mlen);
208 	if (len <= 0) return -EINVAL;
209 
210 	if (rpc_pton(cd->net, buf, len, &address.sa, sizeof(address)) == 0)
211 		return -EINVAL;
212 	switch (address.sa.sa_family) {
213 	case AF_INET:
214 		/* Form a mapped IPv4 address in sin6 */
215 		sin6.sin6_family = AF_INET6;
216 		ipv6_addr_set_v4mapped(address.s4.sin_addr.s_addr,
217 				&sin6.sin6_addr);
218 		break;
219 #if IS_ENABLED(CONFIG_IPV6)
220 	case AF_INET6:
221 		memcpy(&sin6, &address.s6, sizeof(sin6));
222 		break;
223 #endif
224 	default:
225 		return -EINVAL;
226 	}
227 
228 	expiry = get_expiry(&mesg);
229 	if (expiry ==0)
230 		return -EINVAL;
231 
232 	/* domainname, or empty for NEGATIVE */
233 	len = qword_get(&mesg, buf, mlen);
234 	if (len < 0) return -EINVAL;
235 
236 	if (len) {
237 		dom = unix_domain_find(buf);
238 		if (dom == NULL)
239 			return -ENOENT;
240 	} else
241 		dom = NULL;
242 
243 	/* IPv6 scope IDs are ignored for now */
244 	ipmp = __ip_map_lookup(cd, class, &sin6.sin6_addr);
245 	if (ipmp) {
246 		err = __ip_map_update(cd, ipmp,
247 			     container_of(dom, struct unix_domain, h),
248 			     expiry);
249 	} else
250 		err = -ENOMEM;
251 
252 	if (dom)
253 		auth_domain_put(dom);
254 
255 	cache_flush();
256 	return err;
257 }
258 
259 static int ip_map_show(struct seq_file *m,
260 		       struct cache_detail *cd,
261 		       struct cache_head *h)
262 {
263 	struct ip_map *im;
264 	struct in6_addr addr;
265 	char *dom = "-no-domain-";
266 
267 	if (h == NULL) {
268 		seq_puts(m, "#class IP domain\n");
269 		return 0;
270 	}
271 	im = container_of(h, struct ip_map, h);
272 	/* class addr domain */
273 	addr = im->m_addr;
274 
275 	if (test_bit(CACHE_VALID, &h->flags) &&
276 	    !test_bit(CACHE_NEGATIVE, &h->flags))
277 		dom = im->m_client->h.name;
278 
279 	if (ipv6_addr_v4mapped(&addr)) {
280 		seq_printf(m, "%s %pI4 %s\n",
281 			im->m_class, &addr.s6_addr32[3], dom);
282 	} else {
283 		seq_printf(m, "%s %pI6 %s\n", im->m_class, &addr, dom);
284 	}
285 	return 0;
286 }
287 
288 
289 static struct ip_map *__ip_map_lookup(struct cache_detail *cd, char *class,
290 		struct in6_addr *addr)
291 {
292 	struct ip_map ip;
293 	struct cache_head *ch;
294 
295 	strcpy(ip.m_class, class);
296 	ip.m_addr = *addr;
297 	ch = sunrpc_cache_lookup_rcu(cd, &ip.h,
298 				     hash_str(class, IP_HASHBITS) ^
299 				     hash_ip6(addr));
300 
301 	if (ch)
302 		return container_of(ch, struct ip_map, h);
303 	else
304 		return NULL;
305 }
306 
307 static int __ip_map_update(struct cache_detail *cd, struct ip_map *ipm,
308 		struct unix_domain *udom, time64_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 void svcauth_unix_purge(struct net *net)
328 {
329 	struct sunrpc_net *sn;
330 
331 	sn = net_generic(net, sunrpc_net_id);
332 	cache_purge(sn->ip_map_cache);
333 }
334 EXPORT_SYMBOL_GPL(svcauth_unix_purge);
335 
336 static inline struct ip_map *
337 ip_map_cached_get(struct svc_xprt *xprt)
338 {
339 	struct ip_map *ipm = NULL;
340 	struct sunrpc_net *sn;
341 
342 	if (test_bit(XPT_CACHE_AUTH, &xprt->xpt_flags)) {
343 		spin_lock(&xprt->xpt_lock);
344 		ipm = xprt->xpt_auth_cache;
345 		if (ipm != NULL) {
346 			sn = net_generic(xprt->xpt_net, sunrpc_net_id);
347 			if (cache_is_expired(sn->ip_map_cache, &ipm->h)) {
348 				/*
349 				 * The entry has been invalidated since it was
350 				 * remembered, e.g. by a second mount from the
351 				 * same IP address.
352 				 */
353 				xprt->xpt_auth_cache = NULL;
354 				spin_unlock(&xprt->xpt_lock);
355 				cache_put(&ipm->h, sn->ip_map_cache);
356 				return NULL;
357 			}
358 			cache_get(&ipm->h);
359 		}
360 		spin_unlock(&xprt->xpt_lock);
361 	}
362 	return ipm;
363 }
364 
365 static inline void
366 ip_map_cached_put(struct svc_xprt *xprt, struct ip_map *ipm)
367 {
368 	if (test_bit(XPT_CACHE_AUTH, &xprt->xpt_flags)) {
369 		spin_lock(&xprt->xpt_lock);
370 		if (xprt->xpt_auth_cache == NULL) {
371 			/* newly cached, keep the reference */
372 			xprt->xpt_auth_cache = ipm;
373 			ipm = NULL;
374 		}
375 		spin_unlock(&xprt->xpt_lock);
376 	}
377 	if (ipm) {
378 		struct sunrpc_net *sn;
379 
380 		sn = net_generic(xprt->xpt_net, sunrpc_net_id);
381 		cache_put(&ipm->h, sn->ip_map_cache);
382 	}
383 }
384 
385 void
386 svcauth_unix_info_release(struct svc_xprt *xpt)
387 {
388 	struct ip_map *ipm;
389 
390 	ipm = xpt->xpt_auth_cache;
391 	if (ipm != NULL) {
392 		struct sunrpc_net *sn;
393 
394 		sn = net_generic(xpt->xpt_net, sunrpc_net_id);
395 		cache_put(&ipm->h, sn->ip_map_cache);
396 	}
397 }
398 
399 /****************************************************************************
400  * auth.unix.gid cache
401  * simple cache to map a UID to a list of GIDs
402  * because AUTH_UNIX aka AUTH_SYS has a max of UNX_NGROUPS
403  */
404 #define	GID_HASHBITS	8
405 #define	GID_HASHMAX	(1<<GID_HASHBITS)
406 
407 struct unix_gid {
408 	struct cache_head	h;
409 	kuid_t			uid;
410 	struct group_info	*gi;
411 	struct rcu_head		rcu;
412 };
413 
414 static int unix_gid_hash(kuid_t uid)
415 {
416 	return hash_long(from_kuid(&init_user_ns, uid), GID_HASHBITS);
417 }
418 
419 static void unix_gid_free(struct rcu_head *rcu)
420 {
421 	struct unix_gid *ug = container_of(rcu, struct unix_gid, rcu);
422 	struct cache_head *item = &ug->h;
423 
424 	if (test_bit(CACHE_VALID, &item->flags) &&
425 	    !test_bit(CACHE_NEGATIVE, &item->flags))
426 		put_group_info(ug->gi);
427 	kfree(ug);
428 }
429 
430 static void unix_gid_put(struct kref *kref)
431 {
432 	struct cache_head *item = container_of(kref, struct cache_head, ref);
433 	struct unix_gid *ug = container_of(item, struct unix_gid, h);
434 
435 	call_rcu(&ug->rcu, unix_gid_free);
436 }
437 
438 static int unix_gid_match(struct cache_head *corig, struct cache_head *cnew)
439 {
440 	struct unix_gid *orig = container_of(corig, struct unix_gid, h);
441 	struct unix_gid *new = container_of(cnew, struct unix_gid, h);
442 	return uid_eq(orig->uid, new->uid);
443 }
444 static void unix_gid_init(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 	new->uid = item->uid;
449 }
450 static void unix_gid_update(struct cache_head *cnew, struct cache_head *citem)
451 {
452 	struct unix_gid *new = container_of(cnew, struct unix_gid, h);
453 	struct unix_gid *item = container_of(citem, struct unix_gid, h);
454 
455 	get_group_info(item->gi);
456 	new->gi = item->gi;
457 }
458 static struct cache_head *unix_gid_alloc(void)
459 {
460 	struct unix_gid *g = kmalloc(sizeof(*g), GFP_KERNEL);
461 	if (g)
462 		return &g->h;
463 	else
464 		return NULL;
465 }
466 
467 static int unix_gid_upcall(struct cache_detail *cd, struct cache_head *h)
468 {
469 	return sunrpc_cache_pipe_upcall_timeout(cd, h);
470 }
471 
472 static void unix_gid_request(struct cache_detail *cd,
473 			     struct cache_head *h,
474 			     char **bpp, int *blen)
475 {
476 	char tuid[20];
477 	struct unix_gid *ug = container_of(h, struct unix_gid, h);
478 
479 	snprintf(tuid, 20, "%u", from_kuid(&init_user_ns, ug->uid));
480 	qword_add(bpp, blen, tuid);
481 	(*bpp)[-1] = '\n';
482 }
483 
484 static struct unix_gid *unix_gid_lookup(struct cache_detail *cd, kuid_t uid);
485 
486 static int unix_gid_parse(struct cache_detail *cd,
487 			char *mesg, int mlen)
488 {
489 	/* uid expiry Ngid gid0 gid1 ... gidN-1 */
490 	int id;
491 	kuid_t uid;
492 	int gids;
493 	int rv;
494 	int i;
495 	int err;
496 	time64_t expiry;
497 	struct unix_gid ug, *ugp;
498 
499 	if (mesg[mlen - 1] != '\n')
500 		return -EINVAL;
501 	mesg[mlen-1] = 0;
502 
503 	rv = get_int(&mesg, &id);
504 	if (rv)
505 		return -EINVAL;
506 	uid = make_kuid(current_user_ns(), id);
507 	ug.uid = uid;
508 
509 	expiry = get_expiry(&mesg);
510 	if (expiry == 0)
511 		return -EINVAL;
512 
513 	rv = get_int(&mesg, &gids);
514 	if (rv || gids < 0 || gids > 8192)
515 		return -EINVAL;
516 
517 	ug.gi = groups_alloc(gids);
518 	if (!ug.gi)
519 		return -ENOMEM;
520 
521 	for (i = 0 ; i < gids ; i++) {
522 		int gid;
523 		kgid_t kgid;
524 		rv = get_int(&mesg, &gid);
525 		err = -EINVAL;
526 		if (rv)
527 			goto out;
528 		kgid = make_kgid(current_user_ns(), gid);
529 		if (!gid_valid(kgid))
530 			goto out;
531 		ug.gi->gid[i] = kgid;
532 	}
533 
534 	groups_sort(ug.gi);
535 	ugp = unix_gid_lookup(cd, uid);
536 	if (ugp) {
537 		struct cache_head *ch;
538 		ug.h.flags = 0;
539 		ug.h.expiry_time = expiry;
540 		ch = sunrpc_cache_update(cd,
541 					 &ug.h, &ugp->h,
542 					 unix_gid_hash(uid));
543 		if (!ch)
544 			err = -ENOMEM;
545 		else {
546 			err = 0;
547 			cache_put(ch, cd);
548 		}
549 	} else
550 		err = -ENOMEM;
551  out:
552 	if (ug.gi)
553 		put_group_info(ug.gi);
554 	return err;
555 }
556 
557 static int unix_gid_show(struct seq_file *m,
558 			 struct cache_detail *cd,
559 			 struct cache_head *h)
560 {
561 	struct user_namespace *user_ns = m->file->f_cred->user_ns;
562 	struct unix_gid *ug;
563 	int i;
564 	int glen;
565 
566 	if (h == NULL) {
567 		seq_puts(m, "#uid cnt: gids...\n");
568 		return 0;
569 	}
570 	ug = container_of(h, struct unix_gid, h);
571 	if (test_bit(CACHE_VALID, &h->flags) &&
572 	    !test_bit(CACHE_NEGATIVE, &h->flags))
573 		glen = ug->gi->ngroups;
574 	else
575 		glen = 0;
576 
577 	seq_printf(m, "%u %d:", from_kuid_munged(user_ns, ug->uid), glen);
578 	for (i = 0; i < glen; i++)
579 		seq_printf(m, " %d", from_kgid_munged(user_ns, ug->gi->gid[i]));
580 	seq_printf(m, "\n");
581 	return 0;
582 }
583 
584 static const struct cache_detail unix_gid_cache_template = {
585 	.owner		= THIS_MODULE,
586 	.hash_size	= GID_HASHMAX,
587 	.name		= "auth.unix.gid",
588 	.cache_put	= unix_gid_put,
589 	.cache_upcall	= unix_gid_upcall,
590 	.cache_request	= unix_gid_request,
591 	.cache_parse	= unix_gid_parse,
592 	.cache_show	= unix_gid_show,
593 	.match		= unix_gid_match,
594 	.init		= unix_gid_init,
595 	.update		= unix_gid_update,
596 	.alloc		= unix_gid_alloc,
597 };
598 
599 int unix_gid_cache_create(struct net *net)
600 {
601 	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
602 	struct cache_detail *cd;
603 	int err;
604 
605 	cd = cache_create_net(&unix_gid_cache_template, net);
606 	if (IS_ERR(cd))
607 		return PTR_ERR(cd);
608 	err = cache_register_net(cd, net);
609 	if (err) {
610 		cache_destroy_net(cd, net);
611 		return err;
612 	}
613 	sn->unix_gid_cache = cd;
614 	return 0;
615 }
616 
617 void unix_gid_cache_destroy(struct net *net)
618 {
619 	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
620 	struct cache_detail *cd = sn->unix_gid_cache;
621 
622 	sn->unix_gid_cache = NULL;
623 	cache_purge(cd);
624 	cache_unregister_net(cd, net);
625 	cache_destroy_net(cd, net);
626 }
627 
628 static struct unix_gid *unix_gid_lookup(struct cache_detail *cd, kuid_t uid)
629 {
630 	struct unix_gid ug;
631 	struct cache_head *ch;
632 
633 	ug.uid = uid;
634 	ch = sunrpc_cache_lookup_rcu(cd, &ug.h, unix_gid_hash(uid));
635 	if (ch)
636 		return container_of(ch, struct unix_gid, h);
637 	else
638 		return NULL;
639 }
640 
641 static struct group_info *unix_gid_find(kuid_t uid, struct svc_rqst *rqstp)
642 {
643 	struct unix_gid *ug;
644 	struct group_info *gi;
645 	int ret;
646 	struct sunrpc_net *sn = net_generic(rqstp->rq_xprt->xpt_net,
647 					    sunrpc_net_id);
648 
649 	ug = unix_gid_lookup(sn->unix_gid_cache, uid);
650 	if (!ug)
651 		return ERR_PTR(-EAGAIN);
652 	ret = cache_check(sn->unix_gid_cache, &ug->h, &rqstp->rq_chandle);
653 	switch (ret) {
654 	case -ENOENT:
655 		return ERR_PTR(-ENOENT);
656 	case -ETIMEDOUT:
657 		return ERR_PTR(-ESHUTDOWN);
658 	case 0:
659 		gi = get_group_info(ug->gi);
660 		cache_put(&ug->h, sn->unix_gid_cache);
661 		return gi;
662 	default:
663 		return ERR_PTR(-EAGAIN);
664 	}
665 }
666 
667 int
668 svcauth_unix_set_client(struct svc_rqst *rqstp)
669 {
670 	struct sockaddr_in *sin;
671 	struct sockaddr_in6 *sin6, sin6_storage;
672 	struct ip_map *ipm;
673 	struct group_info *gi;
674 	struct svc_cred *cred = &rqstp->rq_cred;
675 	struct svc_xprt *xprt = rqstp->rq_xprt;
676 	struct net *net = xprt->xpt_net;
677 	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
678 
679 	switch (rqstp->rq_addr.ss_family) {
680 	case AF_INET:
681 		sin = svc_addr_in(rqstp);
682 		sin6 = &sin6_storage;
683 		ipv6_addr_set_v4mapped(sin->sin_addr.s_addr, &sin6->sin6_addr);
684 		break;
685 	case AF_INET6:
686 		sin6 = svc_addr_in6(rqstp);
687 		break;
688 	default:
689 		BUG();
690 	}
691 
692 	rqstp->rq_client = NULL;
693 	if (rqstp->rq_proc == 0)
694 		goto out;
695 
696 	rqstp->rq_auth_stat = rpc_autherr_badcred;
697 	ipm = ip_map_cached_get(xprt);
698 	if (ipm == NULL)
699 		ipm = __ip_map_lookup(sn->ip_map_cache, rqstp->rq_server->sv_program->pg_class,
700 				    &sin6->sin6_addr);
701 
702 	if (ipm == NULL)
703 		return SVC_DENIED;
704 
705 	switch (cache_check(sn->ip_map_cache, &ipm->h, &rqstp->rq_chandle)) {
706 		default:
707 			BUG();
708 		case -ETIMEDOUT:
709 			return SVC_CLOSE;
710 		case -EAGAIN:
711 			return SVC_DROP;
712 		case -ENOENT:
713 			return SVC_DENIED;
714 		case 0:
715 			rqstp->rq_client = &ipm->m_client->h;
716 			kref_get(&rqstp->rq_client->ref);
717 			ip_map_cached_put(xprt, ipm);
718 			break;
719 	}
720 
721 	gi = unix_gid_find(cred->cr_uid, rqstp);
722 	switch (PTR_ERR(gi)) {
723 	case -EAGAIN:
724 		return SVC_DROP;
725 	case -ESHUTDOWN:
726 		return SVC_CLOSE;
727 	case -ENOENT:
728 		break;
729 	default:
730 		put_group_info(cred->cr_group_info);
731 		cred->cr_group_info = gi;
732 	}
733 
734 out:
735 	rqstp->rq_auth_stat = rpc_auth_ok;
736 	return SVC_OK;
737 }
738 
739 EXPORT_SYMBOL_GPL(svcauth_unix_set_client);
740 
741 /**
742  * svcauth_null_accept - Decode and validate incoming RPC_AUTH_NULL credential
743  * @rqstp: RPC transaction
744  *
745  * Return values:
746  *   %SVC_OK: Both credential and verifier are valid
747  *   %SVC_DENIED: Credential or verifier is not valid
748  *   %SVC_GARBAGE: Failed to decode credential or verifier
749  *   %SVC_CLOSE: Temporary failure
750  *
751  * rqstp->rq_auth_stat is set as mandated by RFC 5531.
752  */
753 static int
754 svcauth_null_accept(struct svc_rqst *rqstp)
755 {
756 	struct xdr_stream *xdr = &rqstp->rq_arg_stream;
757 	struct svc_cred	*cred = &rqstp->rq_cred;
758 	u32 flavor, len;
759 	void *body;
760 
761 	/* Length of Call's credential body field: */
762 	if (xdr_stream_decode_u32(xdr, &len) < 0)
763 		return SVC_GARBAGE;
764 	if (len != 0) {
765 		rqstp->rq_auth_stat = rpc_autherr_badcred;
766 		return SVC_DENIED;
767 	}
768 
769 	/* Call's verf field: */
770 	if (xdr_stream_decode_opaque_auth(xdr, &flavor, &body, &len) < 0)
771 		return SVC_GARBAGE;
772 	if (flavor != RPC_AUTH_NULL || len != 0) {
773 		rqstp->rq_auth_stat = rpc_autherr_badverf;
774 		return SVC_DENIED;
775 	}
776 
777 	/* Signal that mapping to nobody uid/gid is required */
778 	cred->cr_uid = INVALID_UID;
779 	cred->cr_gid = INVALID_GID;
780 	cred->cr_group_info = groups_alloc(0);
781 	if (cred->cr_group_info == NULL)
782 		return SVC_CLOSE; /* kmalloc failure - client must retry */
783 
784 	if (xdr_stream_encode_opaque_auth(&rqstp->rq_res_stream,
785 					  RPC_AUTH_NULL, NULL, 0) < 0)
786 		return SVC_CLOSE;
787 	if (!svcxdr_set_accept_stat(rqstp))
788 		return SVC_CLOSE;
789 
790 	rqstp->rq_cred.cr_flavor = RPC_AUTH_NULL;
791 	return SVC_OK;
792 }
793 
794 static int
795 svcauth_null_release(struct svc_rqst *rqstp)
796 {
797 	if (rqstp->rq_client)
798 		auth_domain_put(rqstp->rq_client);
799 	rqstp->rq_client = NULL;
800 	if (rqstp->rq_cred.cr_group_info)
801 		put_group_info(rqstp->rq_cred.cr_group_info);
802 	rqstp->rq_cred.cr_group_info = NULL;
803 
804 	return 0; /* don't drop */
805 }
806 
807 
808 struct auth_ops svcauth_null = {
809 	.name		= "null",
810 	.owner		= THIS_MODULE,
811 	.flavour	= RPC_AUTH_NULL,
812 	.accept		= svcauth_null_accept,
813 	.release	= svcauth_null_release,
814 	.set_client	= svcauth_unix_set_client,
815 };
816 
817 
818 /**
819  * svcauth_tls_accept - Decode and validate incoming RPC_AUTH_TLS credential
820  * @rqstp: RPC transaction
821  *
822  * Return values:
823  *   %SVC_OK: Both credential and verifier are valid
824  *   %SVC_DENIED: Credential or verifier is not valid
825  *   %SVC_GARBAGE: Failed to decode credential or verifier
826  *   %SVC_CLOSE: Temporary failure
827  *
828  * rqstp->rq_auth_stat is set as mandated by RFC 5531.
829  */
830 static int
831 svcauth_tls_accept(struct svc_rqst *rqstp)
832 {
833 	struct xdr_stream *xdr = &rqstp->rq_arg_stream;
834 	struct svc_cred	*cred = &rqstp->rq_cred;
835 	u32 flavor, len;
836 	void *body;
837 	__be32 *p;
838 
839 	/* Length of Call's credential body field: */
840 	if (xdr_stream_decode_u32(xdr, &len) < 0)
841 		return SVC_GARBAGE;
842 	if (len != 0) {
843 		rqstp->rq_auth_stat = rpc_autherr_badcred;
844 		return SVC_DENIED;
845 	}
846 
847 	/* Call's verf field: */
848 	if (xdr_stream_decode_opaque_auth(xdr, &flavor, &body, &len) < 0)
849 		return SVC_GARBAGE;
850 	if (flavor != RPC_AUTH_NULL || len != 0) {
851 		rqstp->rq_auth_stat = rpc_autherr_badverf;
852 		return SVC_DENIED;
853 	}
854 
855 	/* AUTH_TLS is not valid on non-NULL procedures */
856 	if (rqstp->rq_proc != 0) {
857 		rqstp->rq_auth_stat = rpc_autherr_badcred;
858 		return SVC_DENIED;
859 	}
860 
861 	/* Signal that mapping to nobody uid/gid is required */
862 	cred->cr_uid = INVALID_UID;
863 	cred->cr_gid = INVALID_GID;
864 	cred->cr_group_info = groups_alloc(0);
865 	if (cred->cr_group_info == NULL)
866 		return SVC_CLOSE;
867 
868 	if (rqstp->rq_xprt->xpt_ops->xpo_start_tls) {
869 		p = xdr_reserve_space(&rqstp->rq_res_stream, XDR_UNIT * 2 + 8);
870 		if (!p)
871 			return SVC_CLOSE;
872 		*p++ = rpc_auth_null;
873 		*p++ = cpu_to_be32(8);
874 		memcpy(p, "STARTTLS", 8);
875 	} else {
876 		if (xdr_stream_encode_opaque_auth(&rqstp->rq_res_stream,
877 						  RPC_AUTH_NULL, NULL, 0) < 0)
878 			return SVC_CLOSE;
879 	}
880 	if (!svcxdr_set_accept_stat(rqstp))
881 		return SVC_CLOSE;
882 
883 	rqstp->rq_cred.cr_flavor = RPC_AUTH_TLS;
884 	return SVC_OK;
885 }
886 
887 struct auth_ops svcauth_tls = {
888 	.name		= "tls",
889 	.owner		= THIS_MODULE,
890 	.flavour	= RPC_AUTH_TLS,
891 	.accept		= svcauth_tls_accept,
892 	.release	= svcauth_null_release,
893 	.set_client	= svcauth_unix_set_client,
894 };
895 
896 
897 /**
898  * svcauth_unix_accept - Decode and validate incoming RPC_AUTH_SYS credential
899  * @rqstp: RPC transaction
900  *
901  * Return values:
902  *   %SVC_OK: Both credential and verifier are valid
903  *   %SVC_DENIED: Credential or verifier is not valid
904  *   %SVC_GARBAGE: Failed to decode credential or verifier
905  *   %SVC_CLOSE: Temporary failure
906  *
907  * rqstp->rq_auth_stat is set as mandated by RFC 5531.
908  */
909 static int
910 svcauth_unix_accept(struct svc_rqst *rqstp)
911 {
912 	struct xdr_stream *xdr = &rqstp->rq_arg_stream;
913 	struct svc_cred	*cred = &rqstp->rq_cred;
914 	struct user_namespace *userns;
915 	u32 flavor, len, i;
916 	void *body;
917 	__be32 *p;
918 
919 	/*
920 	 * This implementation ignores the length of the Call's
921 	 * credential body field and the timestamp and machinename
922 	 * fields.
923 	 */
924 	p = xdr_inline_decode(xdr, XDR_UNIT * 3);
925 	if (!p)
926 		return SVC_GARBAGE;
927 	len = be32_to_cpup(p + 2);
928 	if (len > RPC_MAX_MACHINENAME)
929 		return SVC_GARBAGE;
930 	if (!xdr_inline_decode(xdr, len))
931 		return SVC_GARBAGE;
932 
933 	/*
934 	 * Note: we skip uid_valid()/gid_valid() checks here for
935 	 * backwards compatibility with clients that use -1 id's.
936 	 * Instead, -1 uid or gid is later mapped to the
937 	 * (export-specific) anonymous id by nfsd_setuser.
938 	 * Supplementary gid's will be left alone.
939 	 */
940 	userns = (rqstp->rq_xprt && rqstp->rq_xprt->xpt_cred) ?
941 		rqstp->rq_xprt->xpt_cred->user_ns : &init_user_ns;
942 	if (xdr_stream_decode_u32(xdr, &i) < 0)
943 		return SVC_GARBAGE;
944 	cred->cr_uid = make_kuid(userns, i);
945 	if (xdr_stream_decode_u32(xdr, &i) < 0)
946 		return SVC_GARBAGE;
947 	cred->cr_gid = make_kgid(userns, i);
948 
949 	if (xdr_stream_decode_u32(xdr, &len) < 0)
950 		return SVC_GARBAGE;
951 	if (len > UNX_NGROUPS)
952 		goto badcred;
953 	p = xdr_inline_decode(xdr, XDR_UNIT * len);
954 	if (!p)
955 		return SVC_GARBAGE;
956 	cred->cr_group_info = groups_alloc(len);
957 	if (cred->cr_group_info == NULL)
958 		return SVC_CLOSE;
959 	for (i = 0; i < len; i++) {
960 		kgid_t kgid = make_kgid(userns, be32_to_cpup(p++));
961 		cred->cr_group_info->gid[i] = kgid;
962 	}
963 	groups_sort(cred->cr_group_info);
964 
965 	/* Call's verf field: */
966 	if (xdr_stream_decode_opaque_auth(xdr, &flavor, &body, &len) < 0)
967 		return SVC_GARBAGE;
968 	if (flavor != RPC_AUTH_NULL || len != 0) {
969 		rqstp->rq_auth_stat = rpc_autherr_badverf;
970 		return SVC_DENIED;
971 	}
972 
973 	if (xdr_stream_encode_opaque_auth(&rqstp->rq_res_stream,
974 					  RPC_AUTH_NULL, NULL, 0) < 0)
975 		return SVC_CLOSE;
976 	if (!svcxdr_set_accept_stat(rqstp))
977 		return SVC_CLOSE;
978 
979 	rqstp->rq_cred.cr_flavor = RPC_AUTH_UNIX;
980 	return SVC_OK;
981 
982 badcred:
983 	rqstp->rq_auth_stat = rpc_autherr_badcred;
984 	return SVC_DENIED;
985 }
986 
987 static int
988 svcauth_unix_release(struct svc_rqst *rqstp)
989 {
990 	/* Verifier (such as it is) is already in place.
991 	 */
992 	if (rqstp->rq_client)
993 		auth_domain_put(rqstp->rq_client);
994 	rqstp->rq_client = NULL;
995 	if (rqstp->rq_cred.cr_group_info)
996 		put_group_info(rqstp->rq_cred.cr_group_info);
997 	rqstp->rq_cred.cr_group_info = NULL;
998 
999 	return 0;
1000 }
1001 
1002 
1003 struct auth_ops svcauth_unix = {
1004 	.name		= "unix",
1005 	.owner		= THIS_MODULE,
1006 	.flavour	= RPC_AUTH_UNIX,
1007 	.accept		= svcauth_unix_accept,
1008 	.release	= svcauth_unix_release,
1009 	.domain_release	= svcauth_unix_domain_release,
1010 	.set_client	= svcauth_unix_set_client,
1011 };
1012 
1013 static const struct cache_detail ip_map_cache_template = {
1014 	.owner		= THIS_MODULE,
1015 	.hash_size	= IP_HASHMAX,
1016 	.name		= "auth.unix.ip",
1017 	.cache_put	= ip_map_put,
1018 	.cache_upcall	= ip_map_upcall,
1019 	.cache_request	= ip_map_request,
1020 	.cache_parse	= ip_map_parse,
1021 	.cache_show	= ip_map_show,
1022 	.match		= ip_map_match,
1023 	.init		= ip_map_init,
1024 	.update		= update,
1025 	.alloc		= ip_map_alloc,
1026 };
1027 
1028 int ip_map_cache_create(struct net *net)
1029 {
1030 	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1031 	struct cache_detail *cd;
1032 	int err;
1033 
1034 	cd = cache_create_net(&ip_map_cache_template, net);
1035 	if (IS_ERR(cd))
1036 		return PTR_ERR(cd);
1037 	err = cache_register_net(cd, net);
1038 	if (err) {
1039 		cache_destroy_net(cd, net);
1040 		return err;
1041 	}
1042 	sn->ip_map_cache = cd;
1043 	return 0;
1044 }
1045 
1046 void ip_map_cache_destroy(struct net *net)
1047 {
1048 	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1049 	struct cache_detail *cd = sn->ip_map_cache;
1050 
1051 	sn->ip_map_cache = NULL;
1052 	cache_purge(cd);
1053 	cache_unregister_net(cd, net);
1054 	cache_destroy_net(cd, net);
1055 }
1056