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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Neil Brown <neilb@cse.unsw.edu.au>
4 * J. Bruce Fields <bfields@umich.edu>
5 * Andy Adamson <andros@umich.edu>
6 * Dug Song <dugsong@monkey.org>
7 *
8 * RPCSEC_GSS server authentication.
9 * This implements RPCSEC_GSS as defined in rfc2203 (rpcsec_gss) and rfc2078
10 * (gssapi)
11 *
12 * The RPCSEC_GSS involves three stages:
13 * 1/ context creation
14 * 2/ data exchange
15 * 3/ context destruction
16 *
17 * Context creation is handled largely by upcalls to user-space.
18 * In particular, GSS_Accept_sec_context is handled by an upcall
19 * Data exchange is handled entirely within the kernel
20 * In particular, GSS_GetMIC, GSS_VerifyMIC, GSS_Seal, GSS_Unseal are in-kernel.
21 * Context destruction is handled in-kernel
22 * GSS_Delete_sec_context is in-kernel
23 *
24 * Context creation is initiated by a RPCSEC_GSS_INIT request arriving.
25 * The context handle and gss_token are used as a key into the rpcsec_init cache.
26 * The content of this cache includes some of the outputs of GSS_Accept_sec_context,
27 * being major_status, minor_status, context_handle, reply_token.
28 * These are sent back to the client.
29 * Sequence window management is handled by the kernel. The window size if currently
30 * a compile time constant.
31 *
32 * When user-space is happy that a context is established, it places an entry
33 * in the rpcsec_context cache. The key for this cache is the context_handle.
34 * The content includes:
35 * uid/gidlist - for determining access rights
36 * mechanism type
37 * mechanism specific information, such as a key
38 *
39 */
40
41#include <linux/slab.h>
42#include <linux/types.h>
43#include <linux/module.h>
44#include <linux/pagemap.h>
45#include <linux/user_namespace.h>
46
47#include <linux/sunrpc/auth_gss.h>
48#include <linux/sunrpc/gss_err.h>
49#include <linux/sunrpc/svcauth.h>
50#include <linux/sunrpc/svcauth_gss.h>
51#include <linux/sunrpc/cache.h>
52#include "gss_rpc_upcall.h"
53
54
55#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
56# define RPCDBG_FACILITY RPCDBG_AUTH
57#endif
58
59/* The rpcsec_init cache is used for mapping RPCSEC_GSS_{,CONT_}INIT requests
60 * into replies.
61 *
62 * Key is context handle (\x if empty) and gss_token.
63 * Content is major_status minor_status (integers) context_handle, reply_token.
64 *
65 */
66
67static int netobj_equal(struct xdr_netobj *a, struct xdr_netobj *b)
68{
69 return a->len == b->len && 0 == memcmp(a->data, b->data, a->len);
70}
71
72#define RSI_HASHBITS 6
73#define RSI_HASHMAX (1<<RSI_HASHBITS)
74
75struct rsi {
76 struct cache_head h;
77 struct xdr_netobj in_handle, in_token;
78 struct xdr_netobj out_handle, out_token;
79 int major_status, minor_status;
80 struct rcu_head rcu_head;
81};
82
83static struct rsi *rsi_update(struct cache_detail *cd, struct rsi *new, struct rsi *old);
84static struct rsi *rsi_lookup(struct cache_detail *cd, struct rsi *item);
85
86static void rsi_free(struct rsi *rsii)
87{
88 kfree(rsii->in_handle.data);
89 kfree(rsii->in_token.data);
90 kfree(rsii->out_handle.data);
91 kfree(rsii->out_token.data);
92}
93
94static void rsi_free_rcu(struct rcu_head *head)
95{
96 struct rsi *rsii = container_of(head, struct rsi, rcu_head);
97
98 rsi_free(rsii);
99 kfree(rsii);
100}
101
102static void rsi_put(struct kref *ref)
103{
104 struct rsi *rsii = container_of(ref, struct rsi, h.ref);
105
106 call_rcu(&rsii->rcu_head, rsi_free_rcu);
107}
108
109static inline int rsi_hash(struct rsi *item)
110{
111 return hash_mem(item->in_handle.data, item->in_handle.len, RSI_HASHBITS)
112 ^ hash_mem(item->in_token.data, item->in_token.len, RSI_HASHBITS);
113}
114
115static int rsi_match(struct cache_head *a, struct cache_head *b)
116{
117 struct rsi *item = container_of(a, struct rsi, h);
118 struct rsi *tmp = container_of(b, struct rsi, h);
119 return netobj_equal(&item->in_handle, &tmp->in_handle) &&
120 netobj_equal(&item->in_token, &tmp->in_token);
121}
122
123static int dup_to_netobj(struct xdr_netobj *dst, char *src, int len)
124{
125 dst->len = len;
126 dst->data = (len ? kmemdup(src, len, GFP_KERNEL) : NULL);
127 if (len && !dst->data)
128 return -ENOMEM;
129 return 0;
130}
131
132static inline int dup_netobj(struct xdr_netobj *dst, struct xdr_netobj *src)
133{
134 return dup_to_netobj(dst, src->data, src->len);
135}
136
137static void rsi_init(struct cache_head *cnew, struct cache_head *citem)
138{
139 struct rsi *new = container_of(cnew, struct rsi, h);
140 struct rsi *item = container_of(citem, struct rsi, h);
141
142 new->out_handle.data = NULL;
143 new->out_handle.len = 0;
144 new->out_token.data = NULL;
145 new->out_token.len = 0;
146 new->in_handle.len = item->in_handle.len;
147 item->in_handle.len = 0;
148 new->in_token.len = item->in_token.len;
149 item->in_token.len = 0;
150 new->in_handle.data = item->in_handle.data;
151 item->in_handle.data = NULL;
152 new->in_token.data = item->in_token.data;
153 item->in_token.data = NULL;
154}
155
156static void update_rsi(struct cache_head *cnew, struct cache_head *citem)
157{
158 struct rsi *new = container_of(cnew, struct rsi, h);
159 struct rsi *item = container_of(citem, struct rsi, h);
160
161 BUG_ON(new->out_handle.data || new->out_token.data);
162 new->out_handle.len = item->out_handle.len;
163 item->out_handle.len = 0;
164 new->out_token.len = item->out_token.len;
165 item->out_token.len = 0;
166 new->out_handle.data = item->out_handle.data;
167 item->out_handle.data = NULL;
168 new->out_token.data = item->out_token.data;
169 item->out_token.data = NULL;
170
171 new->major_status = item->major_status;
172 new->minor_status = item->minor_status;
173}
174
175static struct cache_head *rsi_alloc(void)
176{
177 struct rsi *rsii = kmalloc(sizeof(*rsii), GFP_KERNEL);
178 if (rsii)
179 return &rsii->h;
180 else
181 return NULL;
182}
183
184static void rsi_request(struct cache_detail *cd,
185 struct cache_head *h,
186 char **bpp, int *blen)
187{
188 struct rsi *rsii = container_of(h, struct rsi, h);
189
190 qword_addhex(bpp, blen, rsii->in_handle.data, rsii->in_handle.len);
191 qword_addhex(bpp, blen, rsii->in_token.data, rsii->in_token.len);
192 (*bpp)[-1] = '\n';
193}
194
195static int rsi_parse(struct cache_detail *cd,
196 char *mesg, int mlen)
197{
198 /* context token expiry major minor context token */
199 char *buf = mesg;
200 char *ep;
201 int len;
202 struct rsi rsii, *rsip = NULL;
203 time_t expiry;
204 int status = -EINVAL;
205
206 memset(&rsii, 0, sizeof(rsii));
207 /* handle */
208 len = qword_get(&mesg, buf, mlen);
209 if (len < 0)
210 goto out;
211 status = -ENOMEM;
212 if (dup_to_netobj(&rsii.in_handle, buf, len))
213 goto out;
214
215 /* token */
216 len = qword_get(&mesg, buf, mlen);
217 status = -EINVAL;
218 if (len < 0)
219 goto out;
220 status = -ENOMEM;
221 if (dup_to_netobj(&rsii.in_token, buf, len))
222 goto out;
223
224 rsip = rsi_lookup(cd, &rsii);
225 if (!rsip)
226 goto out;
227
228 rsii.h.flags = 0;
229 /* expiry */
230 expiry = get_expiry(&mesg);
231 status = -EINVAL;
232 if (expiry == 0)
233 goto out;
234
235 /* major/minor */
236 len = qword_get(&mesg, buf, mlen);
237 if (len <= 0)
238 goto out;
239 rsii.major_status = simple_strtoul(buf, &ep, 10);
240 if (*ep)
241 goto out;
242 len = qword_get(&mesg, buf, mlen);
243 if (len <= 0)
244 goto out;
245 rsii.minor_status = simple_strtoul(buf, &ep, 10);
246 if (*ep)
247 goto out;
248
249 /* out_handle */
250 len = qword_get(&mesg, buf, mlen);
251 if (len < 0)
252 goto out;
253 status = -ENOMEM;
254 if (dup_to_netobj(&rsii.out_handle, buf, len))
255 goto out;
256
257 /* out_token */
258 len = qword_get(&mesg, buf, mlen);
259 status = -EINVAL;
260 if (len < 0)
261 goto out;
262 status = -ENOMEM;
263 if (dup_to_netobj(&rsii.out_token, buf, len))
264 goto out;
265 rsii.h.expiry_time = expiry;
266 rsip = rsi_update(cd, &rsii, rsip);
267 status = 0;
268out:
269 rsi_free(&rsii);
270 if (rsip)
271 cache_put(&rsip->h, cd);
272 else
273 status = -ENOMEM;
274 return status;
275}
276
277static const struct cache_detail rsi_cache_template = {
278 .owner = THIS_MODULE,
279 .hash_size = RSI_HASHMAX,
280 .name = "auth.rpcsec.init",
281 .cache_put = rsi_put,
282 .cache_request = rsi_request,
283 .cache_parse = rsi_parse,
284 .match = rsi_match,
285 .init = rsi_init,
286 .update = update_rsi,
287 .alloc = rsi_alloc,
288};
289
290static struct rsi *rsi_lookup(struct cache_detail *cd, struct rsi *item)
291{
292 struct cache_head *ch;
293 int hash = rsi_hash(item);
294
295 ch = sunrpc_cache_lookup_rcu(cd, &item->h, hash);
296 if (ch)
297 return container_of(ch, struct rsi, h);
298 else
299 return NULL;
300}
301
302static struct rsi *rsi_update(struct cache_detail *cd, struct rsi *new, struct rsi *old)
303{
304 struct cache_head *ch;
305 int hash = rsi_hash(new);
306
307 ch = sunrpc_cache_update(cd, &new->h,
308 &old->h, hash);
309 if (ch)
310 return container_of(ch, struct rsi, h);
311 else
312 return NULL;
313}
314
315
316/*
317 * The rpcsec_context cache is used to store a context that is
318 * used in data exchange.
319 * The key is a context handle. The content is:
320 * uid, gidlist, mechanism, service-set, mech-specific-data
321 */
322
323#define RSC_HASHBITS 10
324#define RSC_HASHMAX (1<<RSC_HASHBITS)
325
326#define GSS_SEQ_WIN 128
327
328struct gss_svc_seq_data {
329 /* highest seq number seen so far: */
330 int sd_max;
331 /* for i such that sd_max-GSS_SEQ_WIN < i <= sd_max, the i-th bit of
332 * sd_win is nonzero iff sequence number i has been seen already: */
333 unsigned long sd_win[GSS_SEQ_WIN/BITS_PER_LONG];
334 spinlock_t sd_lock;
335};
336
337struct rsc {
338 struct cache_head h;
339 struct xdr_netobj handle;
340 struct svc_cred cred;
341 struct gss_svc_seq_data seqdata;
342 struct gss_ctx *mechctx;
343 struct rcu_head rcu_head;
344};
345
346static struct rsc *rsc_update(struct cache_detail *cd, struct rsc *new, struct rsc *old);
347static struct rsc *rsc_lookup(struct cache_detail *cd, struct rsc *item);
348
349static void rsc_free(struct rsc *rsci)
350{
351 kfree(rsci->handle.data);
352 if (rsci->mechctx)
353 gss_delete_sec_context(&rsci->mechctx);
354 free_svc_cred(&rsci->cred);
355}
356
357static void rsc_free_rcu(struct rcu_head *head)
358{
359 struct rsc *rsci = container_of(head, struct rsc, rcu_head);
360
361 kfree(rsci->handle.data);
362 kfree(rsci);
363}
364
365static void rsc_put(struct kref *ref)
366{
367 struct rsc *rsci = container_of(ref, struct rsc, h.ref);
368
369 if (rsci->mechctx)
370 gss_delete_sec_context(&rsci->mechctx);
371 free_svc_cred(&rsci->cred);
372 call_rcu(&rsci->rcu_head, rsc_free_rcu);
373}
374
375static inline int
376rsc_hash(struct rsc *rsci)
377{
378 return hash_mem(rsci->handle.data, rsci->handle.len, RSC_HASHBITS);
379}
380
381static int
382rsc_match(struct cache_head *a, struct cache_head *b)
383{
384 struct rsc *new = container_of(a, struct rsc, h);
385 struct rsc *tmp = container_of(b, struct rsc, h);
386
387 return netobj_equal(&new->handle, &tmp->handle);
388}
389
390static void
391rsc_init(struct cache_head *cnew, struct cache_head *ctmp)
392{
393 struct rsc *new = container_of(cnew, struct rsc, h);
394 struct rsc *tmp = container_of(ctmp, struct rsc, h);
395
396 new->handle.len = tmp->handle.len;
397 tmp->handle.len = 0;
398 new->handle.data = tmp->handle.data;
399 tmp->handle.data = NULL;
400 new->mechctx = NULL;
401 init_svc_cred(&new->cred);
402}
403
404static void
405update_rsc(struct cache_head *cnew, struct cache_head *ctmp)
406{
407 struct rsc *new = container_of(cnew, struct rsc, h);
408 struct rsc *tmp = container_of(ctmp, struct rsc, h);
409
410 new->mechctx = tmp->mechctx;
411 tmp->mechctx = NULL;
412 memset(&new->seqdata, 0, sizeof(new->seqdata));
413 spin_lock_init(&new->seqdata.sd_lock);
414 new->cred = tmp->cred;
415 init_svc_cred(&tmp->cred);
416}
417
418static struct cache_head *
419rsc_alloc(void)
420{
421 struct rsc *rsci = kmalloc(sizeof(*rsci), GFP_KERNEL);
422 if (rsci)
423 return &rsci->h;
424 else
425 return NULL;
426}
427
428static int rsc_parse(struct cache_detail *cd,
429 char *mesg, int mlen)
430{
431 /* contexthandle expiry [ uid gid N <n gids> mechname ...mechdata... ] */
432 char *buf = mesg;
433 int id;
434 int len, rv;
435 struct rsc rsci, *rscp = NULL;
436 time_t expiry;
437 int status = -EINVAL;
438 struct gss_api_mech *gm = NULL;
439
440 memset(&rsci, 0, sizeof(rsci));
441 /* context handle */
442 len = qword_get(&mesg, buf, mlen);
443 if (len < 0) goto out;
444 status = -ENOMEM;
445 if (dup_to_netobj(&rsci.handle, buf, len))
446 goto out;
447
448 rsci.h.flags = 0;
449 /* expiry */
450 expiry = get_expiry(&mesg);
451 status = -EINVAL;
452 if (expiry == 0)
453 goto out;
454
455 rscp = rsc_lookup(cd, &rsci);
456 if (!rscp)
457 goto out;
458
459 /* uid, or NEGATIVE */
460 rv = get_int(&mesg, &id);
461 if (rv == -EINVAL)
462 goto out;
463 if (rv == -ENOENT)
464 set_bit(CACHE_NEGATIVE, &rsci.h.flags);
465 else {
466 int N, i;
467
468 /*
469 * NOTE: we skip uid_valid()/gid_valid() checks here:
470 * instead, * -1 id's are later mapped to the
471 * (export-specific) anonymous id by nfsd_setuser.
472 *
473 * (But supplementary gid's get no such special
474 * treatment so are checked for validity here.)
475 */
476 /* uid */
477 rsci.cred.cr_uid = make_kuid(current_user_ns(), id);
478
479 /* gid */
480 if (get_int(&mesg, &id))
481 goto out;
482 rsci.cred.cr_gid = make_kgid(current_user_ns(), id);
483
484 /* number of additional gid's */
485 if (get_int(&mesg, &N))
486 goto out;
487 if (N < 0 || N > NGROUPS_MAX)
488 goto out;
489 status = -ENOMEM;
490 rsci.cred.cr_group_info = groups_alloc(N);
491 if (rsci.cred.cr_group_info == NULL)
492 goto out;
493
494 /* gid's */
495 status = -EINVAL;
496 for (i=0; i<N; i++) {
497 kgid_t kgid;
498 if (get_int(&mesg, &id))
499 goto out;
500 kgid = make_kgid(current_user_ns(), id);
501 if (!gid_valid(kgid))
502 goto out;
503 rsci.cred.cr_group_info->gid[i] = kgid;
504 }
505 groups_sort(rsci.cred.cr_group_info);
506
507 /* mech name */
508 len = qword_get(&mesg, buf, mlen);
509 if (len < 0)
510 goto out;
511 gm = rsci.cred.cr_gss_mech = gss_mech_get_by_name(buf);
512 status = -EOPNOTSUPP;
513 if (!gm)
514 goto out;
515
516 status = -EINVAL;
517 /* mech-specific data: */
518 len = qword_get(&mesg, buf, mlen);
519 if (len < 0)
520 goto out;
521 status = gss_import_sec_context(buf, len, gm, &rsci.mechctx,
522 NULL, GFP_KERNEL);
523 if (status)
524 goto out;
525
526 /* get client name */
527 len = qword_get(&mesg, buf, mlen);
528 if (len > 0) {
529 rsci.cred.cr_principal = kstrdup(buf, GFP_KERNEL);
530 if (!rsci.cred.cr_principal) {
531 status = -ENOMEM;
532 goto out;
533 }
534 }
535
536 }
537 rsci.h.expiry_time = expiry;
538 rscp = rsc_update(cd, &rsci, rscp);
539 status = 0;
540out:
541 rsc_free(&rsci);
542 if (rscp)
543 cache_put(&rscp->h, cd);
544 else
545 status = -ENOMEM;
546 return status;
547}
548
549static const struct cache_detail rsc_cache_template = {
550 .owner = THIS_MODULE,
551 .hash_size = RSC_HASHMAX,
552 .name = "auth.rpcsec.context",
553 .cache_put = rsc_put,
554 .cache_parse = rsc_parse,
555 .match = rsc_match,
556 .init = rsc_init,
557 .update = update_rsc,
558 .alloc = rsc_alloc,
559};
560
561static struct rsc *rsc_lookup(struct cache_detail *cd, struct rsc *item)
562{
563 struct cache_head *ch;
564 int hash = rsc_hash(item);
565
566 ch = sunrpc_cache_lookup_rcu(cd, &item->h, hash);
567 if (ch)
568 return container_of(ch, struct rsc, h);
569 else
570 return NULL;
571}
572
573static struct rsc *rsc_update(struct cache_detail *cd, struct rsc *new, struct rsc *old)
574{
575 struct cache_head *ch;
576 int hash = rsc_hash(new);
577
578 ch = sunrpc_cache_update(cd, &new->h,
579 &old->h, hash);
580 if (ch)
581 return container_of(ch, struct rsc, h);
582 else
583 return NULL;
584}
585
586
587static struct rsc *
588gss_svc_searchbyctx(struct cache_detail *cd, struct xdr_netobj *handle)
589{
590 struct rsc rsci;
591 struct rsc *found;
592
593 memset(&rsci, 0, sizeof(rsci));
594 if (dup_to_netobj(&rsci.handle, handle->data, handle->len))
595 return NULL;
596 found = rsc_lookup(cd, &rsci);
597 rsc_free(&rsci);
598 if (!found)
599 return NULL;
600 if (cache_check(cd, &found->h, NULL))
601 return NULL;
602 return found;
603}
604
605/* Implements sequence number algorithm as specified in RFC 2203. */
606static int
607gss_check_seq_num(struct rsc *rsci, int seq_num)
608{
609 struct gss_svc_seq_data *sd = &rsci->seqdata;
610
611 spin_lock(&sd->sd_lock);
612 if (seq_num > sd->sd_max) {
613 if (seq_num >= sd->sd_max + GSS_SEQ_WIN) {
614 memset(sd->sd_win,0,sizeof(sd->sd_win));
615 sd->sd_max = seq_num;
616 } else while (sd->sd_max < seq_num) {
617 sd->sd_max++;
618 __clear_bit(sd->sd_max % GSS_SEQ_WIN, sd->sd_win);
619 }
620 __set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win);
621 goto ok;
622 } else if (seq_num <= sd->sd_max - GSS_SEQ_WIN) {
623 goto drop;
624 }
625 /* sd_max - GSS_SEQ_WIN < seq_num <= sd_max */
626 if (__test_and_set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win))
627 goto drop;
628ok:
629 spin_unlock(&sd->sd_lock);
630 return 1;
631drop:
632 spin_unlock(&sd->sd_lock);
633 return 0;
634}
635
636static inline u32 round_up_to_quad(u32 i)
637{
638 return (i + 3 ) & ~3;
639}
640
641static inline int
642svc_safe_getnetobj(struct kvec *argv, struct xdr_netobj *o)
643{
644 int l;
645
646 if (argv->iov_len < 4)
647 return -1;
648 o->len = svc_getnl(argv);
649 l = round_up_to_quad(o->len);
650 if (argv->iov_len < l)
651 return -1;
652 o->data = argv->iov_base;
653 argv->iov_base += l;
654 argv->iov_len -= l;
655 return 0;
656}
657
658static inline int
659svc_safe_putnetobj(struct kvec *resv, struct xdr_netobj *o)
660{
661 u8 *p;
662
663 if (resv->iov_len + 4 > PAGE_SIZE)
664 return -1;
665 svc_putnl(resv, o->len);
666 p = resv->iov_base + resv->iov_len;
667 resv->iov_len += round_up_to_quad(o->len);
668 if (resv->iov_len > PAGE_SIZE)
669 return -1;
670 memcpy(p, o->data, o->len);
671 memset(p + o->len, 0, round_up_to_quad(o->len) - o->len);
672 return 0;
673}
674
675/*
676 * Verify the checksum on the header and return SVC_OK on success.
677 * Otherwise, return SVC_DROP (in the case of a bad sequence number)
678 * or return SVC_DENIED and indicate error in authp.
679 */
680static int
681gss_verify_header(struct svc_rqst *rqstp, struct rsc *rsci,
682 __be32 *rpcstart, struct rpc_gss_wire_cred *gc, __be32 *authp)
683{
684 struct gss_ctx *ctx_id = rsci->mechctx;
685 struct xdr_buf rpchdr;
686 struct xdr_netobj checksum;
687 u32 flavor = 0;
688 struct kvec *argv = &rqstp->rq_arg.head[0];
689 struct kvec iov;
690
691 /* data to compute the checksum over: */
692 iov.iov_base = rpcstart;
693 iov.iov_len = (u8 *)argv->iov_base - (u8 *)rpcstart;
694 xdr_buf_from_iov(&iov, &rpchdr);
695
696 *authp = rpc_autherr_badverf;
697 if (argv->iov_len < 4)
698 return SVC_DENIED;
699 flavor = svc_getnl(argv);
700 if (flavor != RPC_AUTH_GSS)
701 return SVC_DENIED;
702 if (svc_safe_getnetobj(argv, &checksum))
703 return SVC_DENIED;
704
705 if (rqstp->rq_deferred) /* skip verification of revisited request */
706 return SVC_OK;
707 if (gss_verify_mic(ctx_id, &rpchdr, &checksum) != GSS_S_COMPLETE) {
708 *authp = rpcsec_gsserr_credproblem;
709 return SVC_DENIED;
710 }
711
712 if (gc->gc_seq > MAXSEQ) {
713 dprintk("RPC: svcauth_gss: discarding request with "
714 "large sequence number %d\n", gc->gc_seq);
715 *authp = rpcsec_gsserr_ctxproblem;
716 return SVC_DENIED;
717 }
718 if (!gss_check_seq_num(rsci, gc->gc_seq)) {
719 dprintk("RPC: svcauth_gss: discarding request with "
720 "old sequence number %d\n", gc->gc_seq);
721 return SVC_DROP;
722 }
723 return SVC_OK;
724}
725
726static int
727gss_write_null_verf(struct svc_rqst *rqstp)
728{
729 __be32 *p;
730
731 svc_putnl(rqstp->rq_res.head, RPC_AUTH_NULL);
732 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len;
733 /* don't really need to check if head->iov_len > PAGE_SIZE ... */
734 *p++ = 0;
735 if (!xdr_ressize_check(rqstp, p))
736 return -1;
737 return 0;
738}
739
740static int
741gss_write_verf(struct svc_rqst *rqstp, struct gss_ctx *ctx_id, u32 seq)
742{
743 __be32 *xdr_seq;
744 u32 maj_stat;
745 struct xdr_buf verf_data;
746 struct xdr_netobj mic;
747 __be32 *p;
748 struct kvec iov;
749 int err = -1;
750
751 svc_putnl(rqstp->rq_res.head, RPC_AUTH_GSS);
752 xdr_seq = kmalloc(4, GFP_KERNEL);
753 if (!xdr_seq)
754 return -1;
755 *xdr_seq = htonl(seq);
756
757 iov.iov_base = xdr_seq;
758 iov.iov_len = 4;
759 xdr_buf_from_iov(&iov, &verf_data);
760 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len;
761 mic.data = (u8 *)(p + 1);
762 maj_stat = gss_get_mic(ctx_id, &verf_data, &mic);
763 if (maj_stat != GSS_S_COMPLETE)
764 goto out;
765 *p++ = htonl(mic.len);
766 memset((u8 *)p + mic.len, 0, round_up_to_quad(mic.len) - mic.len);
767 p += XDR_QUADLEN(mic.len);
768 if (!xdr_ressize_check(rqstp, p))
769 goto out;
770 err = 0;
771out:
772 kfree(xdr_seq);
773 return err;
774}
775
776struct gss_domain {
777 struct auth_domain h;
778 u32 pseudoflavor;
779};
780
781static struct auth_domain *
782find_gss_auth_domain(struct gss_ctx *ctx, u32 svc)
783{
784 char *name;
785
786 name = gss_service_to_auth_domain_name(ctx->mech_type, svc);
787 if (!name)
788 return NULL;
789 return auth_domain_find(name);
790}
791
792static struct auth_ops svcauthops_gss;
793
794u32 svcauth_gss_flavor(struct auth_domain *dom)
795{
796 struct gss_domain *gd = container_of(dom, struct gss_domain, h);
797
798 return gd->pseudoflavor;
799}
800
801EXPORT_SYMBOL_GPL(svcauth_gss_flavor);
802
803int
804svcauth_gss_register_pseudoflavor(u32 pseudoflavor, char * name)
805{
806 struct gss_domain *new;
807 struct auth_domain *test;
808 int stat = -ENOMEM;
809
810 new = kmalloc(sizeof(*new), GFP_KERNEL);
811 if (!new)
812 goto out;
813 kref_init(&new->h.ref);
814 new->h.name = kstrdup(name, GFP_KERNEL);
815 if (!new->h.name)
816 goto out_free_dom;
817 new->h.flavour = &svcauthops_gss;
818 new->pseudoflavor = pseudoflavor;
819
820 stat = 0;
821 test = auth_domain_lookup(name, &new->h);
822 if (test != &new->h) { /* Duplicate registration */
823 auth_domain_put(test);
824 kfree(new->h.name);
825 goto out_free_dom;
826 }
827 return 0;
828
829out_free_dom:
830 kfree(new);
831out:
832 return stat;
833}
834
835EXPORT_SYMBOL_GPL(svcauth_gss_register_pseudoflavor);
836
837static inline int
838read_u32_from_xdr_buf(struct xdr_buf *buf, int base, u32 *obj)
839{
840 __be32 raw;
841 int status;
842
843 status = read_bytes_from_xdr_buf(buf, base, &raw, sizeof(*obj));
844 if (status)
845 return status;
846 *obj = ntohl(raw);
847 return 0;
848}
849
850/* It would be nice if this bit of code could be shared with the client.
851 * Obstacles:
852 * The client shouldn't malloc(), would have to pass in own memory.
853 * The server uses base of head iovec as read pointer, while the
854 * client uses separate pointer. */
855static int
856unwrap_integ_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx)
857{
858 int stat = -EINVAL;
859 u32 integ_len, maj_stat;
860 struct xdr_netobj mic;
861 struct xdr_buf integ_buf;
862
863 /* NFS READ normally uses splice to send data in-place. However
864 * the data in cache can change after the reply's MIC is computed
865 * but before the RPC reply is sent. To prevent the client from
866 * rejecting the server-computed MIC in this somewhat rare case,
867 * do not use splice with the GSS integrity service.
868 */
869 clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
870
871 /* Did we already verify the signature on the original pass through? */
872 if (rqstp->rq_deferred)
873 return 0;
874
875 integ_len = svc_getnl(&buf->head[0]);
876 if (integ_len & 3)
877 return stat;
878 if (integ_len > buf->len)
879 return stat;
880 if (xdr_buf_subsegment(buf, &integ_buf, 0, integ_len)) {
881 WARN_ON_ONCE(1);
882 return stat;
883 }
884 /* copy out mic... */
885 if (read_u32_from_xdr_buf(buf, integ_len, &mic.len))
886 return stat;
887 if (mic.len > RPC_MAX_AUTH_SIZE)
888 return stat;
889 mic.data = kmalloc(mic.len, GFP_KERNEL);
890 if (!mic.data)
891 return stat;
892 if (read_bytes_from_xdr_buf(buf, integ_len + 4, mic.data, mic.len))
893 goto out;
894 maj_stat = gss_verify_mic(ctx, &integ_buf, &mic);
895 if (maj_stat != GSS_S_COMPLETE)
896 goto out;
897 if (svc_getnl(&buf->head[0]) != seq)
898 goto out;
899 /* trim off the mic and padding at the end before returning */
900 buf->len -= 4 + round_up_to_quad(mic.len);
901 stat = 0;
902out:
903 kfree(mic.data);
904 return stat;
905}
906
907static inline int
908total_buf_len(struct xdr_buf *buf)
909{
910 return buf->head[0].iov_len + buf->page_len + buf->tail[0].iov_len;
911}
912
913static void
914fix_priv_head(struct xdr_buf *buf, int pad)
915{
916 if (buf->page_len == 0) {
917 /* We need to adjust head and buf->len in tandem in this
918 * case to make svc_defer() work--it finds the original
919 * buffer start using buf->len - buf->head[0].iov_len. */
920 buf->head[0].iov_len -= pad;
921 }
922}
923
924static int
925unwrap_priv_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx)
926{
927 u32 priv_len, maj_stat;
928 int pad, saved_len, remaining_len, offset;
929
930 clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
931
932 priv_len = svc_getnl(&buf->head[0]);
933 if (rqstp->rq_deferred) {
934 /* Already decrypted last time through! The sequence number
935 * check at out_seq is unnecessary but harmless: */
936 goto out_seq;
937 }
938 /* buf->len is the number of bytes from the original start of the
939 * request to the end, where head[0].iov_len is just the bytes
940 * not yet read from the head, so these two values are different: */
941 remaining_len = total_buf_len(buf);
942 if (priv_len > remaining_len)
943 return -EINVAL;
944 pad = remaining_len - priv_len;
945 buf->len -= pad;
946 fix_priv_head(buf, pad);
947
948 /* Maybe it would be better to give gss_unwrap a length parameter: */
949 saved_len = buf->len;
950 buf->len = priv_len;
951 maj_stat = gss_unwrap(ctx, 0, buf);
952 pad = priv_len - buf->len;
953 buf->len = saved_len;
954 buf->len -= pad;
955 /* The upper layers assume the buffer is aligned on 4-byte boundaries.
956 * In the krb5p case, at least, the data ends up offset, so we need to
957 * move it around. */
958 /* XXX: This is very inefficient. It would be better to either do
959 * this while we encrypt, or maybe in the receive code, if we can peak
960 * ahead and work out the service and mechanism there. */
961 offset = buf->head[0].iov_len % 4;
962 if (offset) {
963 buf->buflen = RPCSVC_MAXPAYLOAD;
964 xdr_shift_buf(buf, offset);
965 fix_priv_head(buf, pad);
966 }
967 if (maj_stat != GSS_S_COMPLETE)
968 return -EINVAL;
969out_seq:
970 if (svc_getnl(&buf->head[0]) != seq)
971 return -EINVAL;
972 return 0;
973}
974
975struct gss_svc_data {
976 /* decoded gss client cred: */
977 struct rpc_gss_wire_cred clcred;
978 /* save a pointer to the beginning of the encoded verifier,
979 * for use in encryption/checksumming in svcauth_gss_release: */
980 __be32 *verf_start;
981 struct rsc *rsci;
982};
983
984static int
985svcauth_gss_set_client(struct svc_rqst *rqstp)
986{
987 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
988 struct rsc *rsci = svcdata->rsci;
989 struct rpc_gss_wire_cred *gc = &svcdata->clcred;
990 int stat;
991
992 /*
993 * A gss export can be specified either by:
994 * export *(sec=krb5,rw)
995 * or by
996 * export gss/krb5(rw)
997 * The latter is deprecated; but for backwards compatibility reasons
998 * the nfsd code will still fall back on trying it if the former
999 * doesn't work; so we try to make both available to nfsd, below.
1000 */
1001 rqstp->rq_gssclient = find_gss_auth_domain(rsci->mechctx, gc->gc_svc);
1002 if (rqstp->rq_gssclient == NULL)
1003 return SVC_DENIED;
1004 stat = svcauth_unix_set_client(rqstp);
1005 if (stat == SVC_DROP || stat == SVC_CLOSE)
1006 return stat;
1007 return SVC_OK;
1008}
1009
1010static inline int
1011gss_write_init_verf(struct cache_detail *cd, struct svc_rqst *rqstp,
1012 struct xdr_netobj *out_handle, int *major_status)
1013{
1014 struct rsc *rsci;
1015 int rc;
1016
1017 if (*major_status != GSS_S_COMPLETE)
1018 return gss_write_null_verf(rqstp);
1019 rsci = gss_svc_searchbyctx(cd, out_handle);
1020 if (rsci == NULL) {
1021 *major_status = GSS_S_NO_CONTEXT;
1022 return gss_write_null_verf(rqstp);
1023 }
1024 rc = gss_write_verf(rqstp, rsci->mechctx, GSS_SEQ_WIN);
1025 cache_put(&rsci->h, cd);
1026 return rc;
1027}
1028
1029static inline int
1030gss_read_common_verf(struct rpc_gss_wire_cred *gc,
1031 struct kvec *argv, __be32 *authp,
1032 struct xdr_netobj *in_handle)
1033{
1034 /* Read the verifier; should be NULL: */
1035 *authp = rpc_autherr_badverf;
1036 if (argv->iov_len < 2 * 4)
1037 return SVC_DENIED;
1038 if (svc_getnl(argv) != RPC_AUTH_NULL)
1039 return SVC_DENIED;
1040 if (svc_getnl(argv) != 0)
1041 return SVC_DENIED;
1042 /* Martial context handle and token for upcall: */
1043 *authp = rpc_autherr_badcred;
1044 if (gc->gc_proc == RPC_GSS_PROC_INIT && gc->gc_ctx.len != 0)
1045 return SVC_DENIED;
1046 if (dup_netobj(in_handle, &gc->gc_ctx))
1047 return SVC_CLOSE;
1048 *authp = rpc_autherr_badverf;
1049
1050 return 0;
1051}
1052
1053static inline int
1054gss_read_verf(struct rpc_gss_wire_cred *gc,
1055 struct kvec *argv, __be32 *authp,
1056 struct xdr_netobj *in_handle,
1057 struct xdr_netobj *in_token)
1058{
1059 struct xdr_netobj tmpobj;
1060 int res;
1061
1062 res = gss_read_common_verf(gc, argv, authp, in_handle);
1063 if (res)
1064 return res;
1065
1066 if (svc_safe_getnetobj(argv, &tmpobj)) {
1067 kfree(in_handle->data);
1068 return SVC_DENIED;
1069 }
1070 if (dup_netobj(in_token, &tmpobj)) {
1071 kfree(in_handle->data);
1072 return SVC_CLOSE;
1073 }
1074
1075 return 0;
1076}
1077
1078/* Ok this is really heavily depending on a set of semantics in
1079 * how rqstp is set up by svc_recv and pages laid down by the
1080 * server when reading a request. We are basically guaranteed that
1081 * the token lays all down linearly across a set of pages, starting
1082 * at iov_base in rq_arg.head[0] which happens to be the first of a
1083 * set of pages stored in rq_pages[].
1084 * rq_arg.head[0].iov_base will provide us the page_base to pass
1085 * to the upcall.
1086 */
1087static inline int
1088gss_read_proxy_verf(struct svc_rqst *rqstp,
1089 struct rpc_gss_wire_cred *gc, __be32 *authp,
1090 struct xdr_netobj *in_handle,
1091 struct gssp_in_token *in_token)
1092{
1093 struct kvec *argv = &rqstp->rq_arg.head[0];
1094 u32 inlen;
1095 int res;
1096
1097 res = gss_read_common_verf(gc, argv, authp, in_handle);
1098 if (res)
1099 return res;
1100
1101 inlen = svc_getnl(argv);
1102 if (inlen > (argv->iov_len + rqstp->rq_arg.page_len))
1103 return SVC_DENIED;
1104
1105 in_token->pages = rqstp->rq_pages;
1106 in_token->page_base = (ulong)argv->iov_base & ~PAGE_MASK;
1107 in_token->page_len = inlen;
1108
1109 return 0;
1110}
1111
1112static inline int
1113gss_write_resv(struct kvec *resv, size_t size_limit,
1114 struct xdr_netobj *out_handle, struct xdr_netobj *out_token,
1115 int major_status, int minor_status)
1116{
1117 if (resv->iov_len + 4 > size_limit)
1118 return -1;
1119 svc_putnl(resv, RPC_SUCCESS);
1120 if (svc_safe_putnetobj(resv, out_handle))
1121 return -1;
1122 if (resv->iov_len + 3 * 4 > size_limit)
1123 return -1;
1124 svc_putnl(resv, major_status);
1125 svc_putnl(resv, minor_status);
1126 svc_putnl(resv, GSS_SEQ_WIN);
1127 if (svc_safe_putnetobj(resv, out_token))
1128 return -1;
1129 return 0;
1130}
1131
1132/*
1133 * Having read the cred already and found we're in the context
1134 * initiation case, read the verifier and initiate (or check the results
1135 * of) upcalls to userspace for help with context initiation. If
1136 * the upcall results are available, write the verifier and result.
1137 * Otherwise, drop the request pending an answer to the upcall.
1138 */
1139static int svcauth_gss_legacy_init(struct svc_rqst *rqstp,
1140 struct rpc_gss_wire_cred *gc, __be32 *authp)
1141{
1142 struct kvec *argv = &rqstp->rq_arg.head[0];
1143 struct kvec *resv = &rqstp->rq_res.head[0];
1144 struct rsi *rsip, rsikey;
1145 int ret;
1146 struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id);
1147
1148 memset(&rsikey, 0, sizeof(rsikey));
1149 ret = gss_read_verf(gc, argv, authp,
1150 &rsikey.in_handle, &rsikey.in_token);
1151 if (ret)
1152 return ret;
1153
1154 /* Perform upcall, or find upcall result: */
1155 rsip = rsi_lookup(sn->rsi_cache, &rsikey);
1156 rsi_free(&rsikey);
1157 if (!rsip)
1158 return SVC_CLOSE;
1159 if (cache_check(sn->rsi_cache, &rsip->h, &rqstp->rq_chandle) < 0)
1160 /* No upcall result: */
1161 return SVC_CLOSE;
1162
1163 ret = SVC_CLOSE;
1164 /* Got an answer to the upcall; use it: */
1165 if (gss_write_init_verf(sn->rsc_cache, rqstp,
1166 &rsip->out_handle, &rsip->major_status))
1167 goto out;
1168 if (gss_write_resv(resv, PAGE_SIZE,
1169 &rsip->out_handle, &rsip->out_token,
1170 rsip->major_status, rsip->minor_status))
1171 goto out;
1172
1173 ret = SVC_COMPLETE;
1174out:
1175 cache_put(&rsip->h, sn->rsi_cache);
1176 return ret;
1177}
1178
1179static int gss_proxy_save_rsc(struct cache_detail *cd,
1180 struct gssp_upcall_data *ud,
1181 uint64_t *handle)
1182{
1183 struct rsc rsci, *rscp = NULL;
1184 static atomic64_t ctxhctr;
1185 long long ctxh;
1186 struct gss_api_mech *gm = NULL;
1187 time_t expiry;
1188 int status = -EINVAL;
1189
1190 memset(&rsci, 0, sizeof(rsci));
1191 /* context handle */
1192 status = -ENOMEM;
1193 /* the handle needs to be just a unique id,
1194 * use a static counter */
1195 ctxh = atomic64_inc_return(&ctxhctr);
1196
1197 /* make a copy for the caller */
1198 *handle = ctxh;
1199
1200 /* make a copy for the rsc cache */
1201 if (dup_to_netobj(&rsci.handle, (char *)handle, sizeof(uint64_t)))
1202 goto out;
1203 rscp = rsc_lookup(cd, &rsci);
1204 if (!rscp)
1205 goto out;
1206
1207 /* creds */
1208 if (!ud->found_creds) {
1209 /* userspace seem buggy, we should always get at least a
1210 * mapping to nobody */
1211 dprintk("RPC: No creds found!\n");
1212 goto out;
1213 } else {
1214
1215 /* steal creds */
1216 rsci.cred = ud->creds;
1217 memset(&ud->creds, 0, sizeof(struct svc_cred));
1218
1219 status = -EOPNOTSUPP;
1220 /* get mech handle from OID */
1221 gm = gss_mech_get_by_OID(&ud->mech_oid);
1222 if (!gm)
1223 goto out;
1224 rsci.cred.cr_gss_mech = gm;
1225
1226 status = -EINVAL;
1227 /* mech-specific data: */
1228 status = gss_import_sec_context(ud->out_handle.data,
1229 ud->out_handle.len,
1230 gm, &rsci.mechctx,
1231 &expiry, GFP_KERNEL);
1232 if (status)
1233 goto out;
1234 }
1235
1236 rsci.h.expiry_time = expiry;
1237 rscp = rsc_update(cd, &rsci, rscp);
1238 status = 0;
1239out:
1240 rsc_free(&rsci);
1241 if (rscp)
1242 cache_put(&rscp->h, cd);
1243 else
1244 status = -ENOMEM;
1245 return status;
1246}
1247
1248static int svcauth_gss_proxy_init(struct svc_rqst *rqstp,
1249 struct rpc_gss_wire_cred *gc, __be32 *authp)
1250{
1251 struct kvec *resv = &rqstp->rq_res.head[0];
1252 struct xdr_netobj cli_handle;
1253 struct gssp_upcall_data ud;
1254 uint64_t handle;
1255 int status;
1256 int ret;
1257 struct net *net = SVC_NET(rqstp);
1258 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1259
1260 memset(&ud, 0, sizeof(ud));
1261 ret = gss_read_proxy_verf(rqstp, gc, authp,
1262 &ud.in_handle, &ud.in_token);
1263 if (ret)
1264 return ret;
1265
1266 ret = SVC_CLOSE;
1267
1268 /* Perform synchronous upcall to gss-proxy */
1269 status = gssp_accept_sec_context_upcall(net, &ud);
1270 if (status)
1271 goto out;
1272
1273 dprintk("RPC: svcauth_gss: gss major status = %d "
1274 "minor status = %d\n",
1275 ud.major_status, ud.minor_status);
1276
1277 switch (ud.major_status) {
1278 case GSS_S_CONTINUE_NEEDED:
1279 cli_handle = ud.out_handle;
1280 break;
1281 case GSS_S_COMPLETE:
1282 status = gss_proxy_save_rsc(sn->rsc_cache, &ud, &handle);
1283 if (status)
1284 goto out;
1285 cli_handle.data = (u8 *)&handle;
1286 cli_handle.len = sizeof(handle);
1287 break;
1288 default:
1289 ret = SVC_CLOSE;
1290 goto out;
1291 }
1292
1293 /* Got an answer to the upcall; use it: */
1294 if (gss_write_init_verf(sn->rsc_cache, rqstp,
1295 &cli_handle, &ud.major_status))
1296 goto out;
1297 if (gss_write_resv(resv, PAGE_SIZE,
1298 &cli_handle, &ud.out_token,
1299 ud.major_status, ud.minor_status))
1300 goto out;
1301
1302 ret = SVC_COMPLETE;
1303out:
1304 gssp_free_upcall_data(&ud);
1305 return ret;
1306}
1307
1308/*
1309 * Try to set the sn->use_gss_proxy variable to a new value. We only allow
1310 * it to be changed if it's currently undefined (-1). If it's any other value
1311 * then return -EBUSY unless the type wouldn't have changed anyway.
1312 */
1313static int set_gss_proxy(struct net *net, int type)
1314{
1315 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1316 int ret;
1317
1318 WARN_ON_ONCE(type != 0 && type != 1);
1319 ret = cmpxchg(&sn->use_gss_proxy, -1, type);
1320 if (ret != -1 && ret != type)
1321 return -EBUSY;
1322 return 0;
1323}
1324
1325static bool use_gss_proxy(struct net *net)
1326{
1327 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1328
1329 /* If use_gss_proxy is still undefined, then try to disable it */
1330 if (sn->use_gss_proxy == -1)
1331 set_gss_proxy(net, 0);
1332 return sn->use_gss_proxy;
1333}
1334
1335#ifdef CONFIG_PROC_FS
1336
1337static ssize_t write_gssp(struct file *file, const char __user *buf,
1338 size_t count, loff_t *ppos)
1339{
1340 struct net *net = PDE_DATA(file_inode(file));
1341 char tbuf[20];
1342 unsigned long i;
1343 int res;
1344
1345 if (*ppos || count > sizeof(tbuf)-1)
1346 return -EINVAL;
1347 if (copy_from_user(tbuf, buf, count))
1348 return -EFAULT;
1349
1350 tbuf[count] = 0;
1351 res = kstrtoul(tbuf, 0, &i);
1352 if (res)
1353 return res;
1354 if (i != 1)
1355 return -EINVAL;
1356 res = set_gssp_clnt(net);
1357 if (res)
1358 return res;
1359 res = set_gss_proxy(net, 1);
1360 if (res)
1361 return res;
1362 return count;
1363}
1364
1365static ssize_t read_gssp(struct file *file, char __user *buf,
1366 size_t count, loff_t *ppos)
1367{
1368 struct net *net = PDE_DATA(file_inode(file));
1369 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1370 unsigned long p = *ppos;
1371 char tbuf[10];
1372 size_t len;
1373
1374 snprintf(tbuf, sizeof(tbuf), "%d\n", sn->use_gss_proxy);
1375 len = strlen(tbuf);
1376 if (p >= len)
1377 return 0;
1378 len -= p;
1379 if (len > count)
1380 len = count;
1381 if (copy_to_user(buf, (void *)(tbuf+p), len))
1382 return -EFAULT;
1383 *ppos += len;
1384 return len;
1385}
1386
1387static const struct file_operations use_gss_proxy_ops = {
1388 .open = nonseekable_open,
1389 .write = write_gssp,
1390 .read = read_gssp,
1391};
1392
1393static int create_use_gss_proxy_proc_entry(struct net *net)
1394{
1395 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1396 struct proc_dir_entry **p = &sn->use_gssp_proc;
1397
1398 sn->use_gss_proxy = -1;
1399 *p = proc_create_data("use-gss-proxy", S_IFREG | 0600,
1400 sn->proc_net_rpc,
1401 &use_gss_proxy_ops, net);
1402 if (!*p)
1403 return -ENOMEM;
1404 init_gssp_clnt(sn);
1405 return 0;
1406}
1407
1408static void destroy_use_gss_proxy_proc_entry(struct net *net)
1409{
1410 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1411
1412 if (sn->use_gssp_proc) {
1413 remove_proc_entry("use-gss-proxy", sn->proc_net_rpc);
1414 clear_gssp_clnt(sn);
1415 }
1416}
1417#else /* CONFIG_PROC_FS */
1418
1419static int create_use_gss_proxy_proc_entry(struct net *net)
1420{
1421 return 0;
1422}
1423
1424static void destroy_use_gss_proxy_proc_entry(struct net *net) {}
1425
1426#endif /* CONFIG_PROC_FS */
1427
1428/*
1429 * Accept an rpcsec packet.
1430 * If context establishment, punt to user space
1431 * If data exchange, verify/decrypt
1432 * If context destruction, handle here
1433 * In the context establishment and destruction case we encode
1434 * response here and return SVC_COMPLETE.
1435 */
1436static int
1437svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
1438{
1439 struct kvec *argv = &rqstp->rq_arg.head[0];
1440 struct kvec *resv = &rqstp->rq_res.head[0];
1441 u32 crlen;
1442 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
1443 struct rpc_gss_wire_cred *gc;
1444 struct rsc *rsci = NULL;
1445 __be32 *rpcstart;
1446 __be32 *reject_stat = resv->iov_base + resv->iov_len;
1447 int ret;
1448 struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id);
1449
1450 dprintk("RPC: svcauth_gss: argv->iov_len = %zd\n",
1451 argv->iov_len);
1452
1453 *authp = rpc_autherr_badcred;
1454 if (!svcdata)
1455 svcdata = kmalloc(sizeof(*svcdata), GFP_KERNEL);
1456 if (!svcdata)
1457 goto auth_err;
1458 rqstp->rq_auth_data = svcdata;
1459 svcdata->verf_start = NULL;
1460 svcdata->rsci = NULL;
1461 gc = &svcdata->clcred;
1462
1463 /* start of rpc packet is 7 u32's back from here:
1464 * xid direction rpcversion prog vers proc flavour
1465 */
1466 rpcstart = argv->iov_base;
1467 rpcstart -= 7;
1468
1469 /* credential is:
1470 * version(==1), proc(0,1,2,3), seq, service (1,2,3), handle
1471 * at least 5 u32s, and is preceded by length, so that makes 6.
1472 */
1473
1474 if (argv->iov_len < 5 * 4)
1475 goto auth_err;
1476 crlen = svc_getnl(argv);
1477 if (svc_getnl(argv) != RPC_GSS_VERSION)
1478 goto auth_err;
1479 gc->gc_proc = svc_getnl(argv);
1480 gc->gc_seq = svc_getnl(argv);
1481 gc->gc_svc = svc_getnl(argv);
1482 if (svc_safe_getnetobj(argv, &gc->gc_ctx))
1483 goto auth_err;
1484 if (crlen != round_up_to_quad(gc->gc_ctx.len) + 5 * 4)
1485 goto auth_err;
1486
1487 if ((gc->gc_proc != RPC_GSS_PROC_DATA) && (rqstp->rq_proc != 0))
1488 goto auth_err;
1489
1490 *authp = rpc_autherr_badverf;
1491 switch (gc->gc_proc) {
1492 case RPC_GSS_PROC_INIT:
1493 case RPC_GSS_PROC_CONTINUE_INIT:
1494 if (use_gss_proxy(SVC_NET(rqstp)))
1495 return svcauth_gss_proxy_init(rqstp, gc, authp);
1496 else
1497 return svcauth_gss_legacy_init(rqstp, gc, authp);
1498 case RPC_GSS_PROC_DATA:
1499 case RPC_GSS_PROC_DESTROY:
1500 /* Look up the context, and check the verifier: */
1501 *authp = rpcsec_gsserr_credproblem;
1502 rsci = gss_svc_searchbyctx(sn->rsc_cache, &gc->gc_ctx);
1503 if (!rsci)
1504 goto auth_err;
1505 switch (gss_verify_header(rqstp, rsci, rpcstart, gc, authp)) {
1506 case SVC_OK:
1507 break;
1508 case SVC_DENIED:
1509 goto auth_err;
1510 case SVC_DROP:
1511 goto drop;
1512 }
1513 break;
1514 default:
1515 *authp = rpc_autherr_rejectedcred;
1516 goto auth_err;
1517 }
1518
1519 /* now act upon the command: */
1520 switch (gc->gc_proc) {
1521 case RPC_GSS_PROC_DESTROY:
1522 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
1523 goto auth_err;
1524 /* Delete the entry from the cache_list and call cache_put */
1525 sunrpc_cache_unhash(sn->rsc_cache, &rsci->h);
1526 if (resv->iov_len + 4 > PAGE_SIZE)
1527 goto drop;
1528 svc_putnl(resv, RPC_SUCCESS);
1529 goto complete;
1530 case RPC_GSS_PROC_DATA:
1531 *authp = rpcsec_gsserr_ctxproblem;
1532 svcdata->verf_start = resv->iov_base + resv->iov_len;
1533 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
1534 goto auth_err;
1535 rqstp->rq_cred = rsci->cred;
1536 get_group_info(rsci->cred.cr_group_info);
1537 *authp = rpc_autherr_badcred;
1538 switch (gc->gc_svc) {
1539 case RPC_GSS_SVC_NONE:
1540 break;
1541 case RPC_GSS_SVC_INTEGRITY:
1542 /* placeholders for length and seq. number: */
1543 svc_putnl(resv, 0);
1544 svc_putnl(resv, 0);
1545 if (unwrap_integ_data(rqstp, &rqstp->rq_arg,
1546 gc->gc_seq, rsci->mechctx))
1547 goto garbage_args;
1548 rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE;
1549 break;
1550 case RPC_GSS_SVC_PRIVACY:
1551 /* placeholders for length and seq. number: */
1552 svc_putnl(resv, 0);
1553 svc_putnl(resv, 0);
1554 if (unwrap_priv_data(rqstp, &rqstp->rq_arg,
1555 gc->gc_seq, rsci->mechctx))
1556 goto garbage_args;
1557 rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE * 2;
1558 break;
1559 default:
1560 goto auth_err;
1561 }
1562 svcdata->rsci = rsci;
1563 cache_get(&rsci->h);
1564 rqstp->rq_cred.cr_flavor = gss_svc_to_pseudoflavor(
1565 rsci->mechctx->mech_type,
1566 GSS_C_QOP_DEFAULT,
1567 gc->gc_svc);
1568 ret = SVC_OK;
1569 goto out;
1570 }
1571garbage_args:
1572 ret = SVC_GARBAGE;
1573 goto out;
1574auth_err:
1575 /* Restore write pointer to its original value: */
1576 xdr_ressize_check(rqstp, reject_stat);
1577 ret = SVC_DENIED;
1578 goto out;
1579complete:
1580 ret = SVC_COMPLETE;
1581 goto out;
1582drop:
1583 ret = SVC_CLOSE;
1584out:
1585 if (rsci)
1586 cache_put(&rsci->h, sn->rsc_cache);
1587 return ret;
1588}
1589
1590static __be32 *
1591svcauth_gss_prepare_to_wrap(struct xdr_buf *resbuf, struct gss_svc_data *gsd)
1592{
1593 __be32 *p;
1594 u32 verf_len;
1595
1596 p = gsd->verf_start;
1597 gsd->verf_start = NULL;
1598
1599 /* If the reply stat is nonzero, don't wrap: */
1600 if (*(p-1) != rpc_success)
1601 return NULL;
1602 /* Skip the verifier: */
1603 p += 1;
1604 verf_len = ntohl(*p++);
1605 p += XDR_QUADLEN(verf_len);
1606 /* move accept_stat to right place: */
1607 memcpy(p, p + 2, 4);
1608 /* Also don't wrap if the accept stat is nonzero: */
1609 if (*p != rpc_success) {
1610 resbuf->head[0].iov_len -= 2 * 4;
1611 return NULL;
1612 }
1613 p++;
1614 return p;
1615}
1616
1617static inline int
1618svcauth_gss_wrap_resp_integ(struct svc_rqst *rqstp)
1619{
1620 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1621 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1622 struct xdr_buf *resbuf = &rqstp->rq_res;
1623 struct xdr_buf integ_buf;
1624 struct xdr_netobj mic;
1625 struct kvec *resv;
1626 __be32 *p;
1627 int integ_offset, integ_len;
1628 int stat = -EINVAL;
1629
1630 p = svcauth_gss_prepare_to_wrap(resbuf, gsd);
1631 if (p == NULL)
1632 goto out;
1633 integ_offset = (u8 *)(p + 1) - (u8 *)resbuf->head[0].iov_base;
1634 integ_len = resbuf->len - integ_offset;
1635 BUG_ON(integ_len % 4);
1636 *p++ = htonl(integ_len);
1637 *p++ = htonl(gc->gc_seq);
1638 if (xdr_buf_subsegment(resbuf, &integ_buf, integ_offset, integ_len)) {
1639 WARN_ON_ONCE(1);
1640 goto out_err;
1641 }
1642 if (resbuf->tail[0].iov_base == NULL) {
1643 if (resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1644 goto out_err;
1645 resbuf->tail[0].iov_base = resbuf->head[0].iov_base
1646 + resbuf->head[0].iov_len;
1647 resbuf->tail[0].iov_len = 0;
1648 }
1649 resv = &resbuf->tail[0];
1650 mic.data = (u8 *)resv->iov_base + resv->iov_len + 4;
1651 if (gss_get_mic(gsd->rsci->mechctx, &integ_buf, &mic))
1652 goto out_err;
1653 svc_putnl(resv, mic.len);
1654 memset(mic.data + mic.len, 0,
1655 round_up_to_quad(mic.len) - mic.len);
1656 resv->iov_len += XDR_QUADLEN(mic.len) << 2;
1657 /* not strictly required: */
1658 resbuf->len += XDR_QUADLEN(mic.len) << 2;
1659 BUG_ON(resv->iov_len > PAGE_SIZE);
1660out:
1661 stat = 0;
1662out_err:
1663 return stat;
1664}
1665
1666static inline int
1667svcauth_gss_wrap_resp_priv(struct svc_rqst *rqstp)
1668{
1669 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1670 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1671 struct xdr_buf *resbuf = &rqstp->rq_res;
1672 struct page **inpages = NULL;
1673 __be32 *p, *len;
1674 int offset;
1675 int pad;
1676
1677 p = svcauth_gss_prepare_to_wrap(resbuf, gsd);
1678 if (p == NULL)
1679 return 0;
1680 len = p++;
1681 offset = (u8 *)p - (u8 *)resbuf->head[0].iov_base;
1682 *p++ = htonl(gc->gc_seq);
1683 inpages = resbuf->pages;
1684 /* XXX: Would be better to write some xdr helper functions for
1685 * nfs{2,3,4}xdr.c that place the data right, instead of copying: */
1686
1687 /*
1688 * If there is currently tail data, make sure there is
1689 * room for the head, tail, and 2 * RPC_MAX_AUTH_SIZE in
1690 * the page, and move the current tail data such that
1691 * there is RPC_MAX_AUTH_SIZE slack space available in
1692 * both the head and tail.
1693 */
1694 if (resbuf->tail[0].iov_base) {
1695 BUG_ON(resbuf->tail[0].iov_base >= resbuf->head[0].iov_base
1696 + PAGE_SIZE);
1697 BUG_ON(resbuf->tail[0].iov_base < resbuf->head[0].iov_base);
1698 if (resbuf->tail[0].iov_len + resbuf->head[0].iov_len
1699 + 2 * RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1700 return -ENOMEM;
1701 memmove(resbuf->tail[0].iov_base + RPC_MAX_AUTH_SIZE,
1702 resbuf->tail[0].iov_base,
1703 resbuf->tail[0].iov_len);
1704 resbuf->tail[0].iov_base += RPC_MAX_AUTH_SIZE;
1705 }
1706 /*
1707 * If there is no current tail data, make sure there is
1708 * room for the head data, and 2 * RPC_MAX_AUTH_SIZE in the
1709 * allotted page, and set up tail information such that there
1710 * is RPC_MAX_AUTH_SIZE slack space available in both the
1711 * head and tail.
1712 */
1713 if (resbuf->tail[0].iov_base == NULL) {
1714 if (resbuf->head[0].iov_len + 2*RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1715 return -ENOMEM;
1716 resbuf->tail[0].iov_base = resbuf->head[0].iov_base
1717 + resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE;
1718 resbuf->tail[0].iov_len = 0;
1719 }
1720 if (gss_wrap(gsd->rsci->mechctx, offset, resbuf, inpages))
1721 return -ENOMEM;
1722 *len = htonl(resbuf->len - offset);
1723 pad = 3 - ((resbuf->len - offset - 1)&3);
1724 p = (__be32 *)(resbuf->tail[0].iov_base + resbuf->tail[0].iov_len);
1725 memset(p, 0, pad);
1726 resbuf->tail[0].iov_len += pad;
1727 resbuf->len += pad;
1728 return 0;
1729}
1730
1731static int
1732svcauth_gss_release(struct svc_rqst *rqstp)
1733{
1734 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1735 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1736 struct xdr_buf *resbuf = &rqstp->rq_res;
1737 int stat = -EINVAL;
1738 struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id);
1739
1740 if (gc->gc_proc != RPC_GSS_PROC_DATA)
1741 goto out;
1742 /* Release can be called twice, but we only wrap once. */
1743 if (gsd->verf_start == NULL)
1744 goto out;
1745 /* normally not set till svc_send, but we need it here: */
1746 /* XXX: what for? Do we mess it up the moment we call svc_putu32
1747 * or whatever? */
1748 resbuf->len = total_buf_len(resbuf);
1749 switch (gc->gc_svc) {
1750 case RPC_GSS_SVC_NONE:
1751 break;
1752 case RPC_GSS_SVC_INTEGRITY:
1753 stat = svcauth_gss_wrap_resp_integ(rqstp);
1754 if (stat)
1755 goto out_err;
1756 break;
1757 case RPC_GSS_SVC_PRIVACY:
1758 stat = svcauth_gss_wrap_resp_priv(rqstp);
1759 if (stat)
1760 goto out_err;
1761 break;
1762 /*
1763 * For any other gc_svc value, svcauth_gss_accept() already set
1764 * the auth_error appropriately; just fall through:
1765 */
1766 }
1767
1768out:
1769 stat = 0;
1770out_err:
1771 if (rqstp->rq_client)
1772 auth_domain_put(rqstp->rq_client);
1773 rqstp->rq_client = NULL;
1774 if (rqstp->rq_gssclient)
1775 auth_domain_put(rqstp->rq_gssclient);
1776 rqstp->rq_gssclient = NULL;
1777 if (rqstp->rq_cred.cr_group_info)
1778 put_group_info(rqstp->rq_cred.cr_group_info);
1779 rqstp->rq_cred.cr_group_info = NULL;
1780 if (gsd->rsci)
1781 cache_put(&gsd->rsci->h, sn->rsc_cache);
1782 gsd->rsci = NULL;
1783
1784 return stat;
1785}
1786
1787static void
1788svcauth_gss_domain_release_rcu(struct rcu_head *head)
1789{
1790 struct auth_domain *dom = container_of(head, struct auth_domain, rcu_head);
1791 struct gss_domain *gd = container_of(dom, struct gss_domain, h);
1792
1793 kfree(dom->name);
1794 kfree(gd);
1795}
1796
1797static void
1798svcauth_gss_domain_release(struct auth_domain *dom)
1799{
1800 call_rcu(&dom->rcu_head, svcauth_gss_domain_release_rcu);
1801}
1802
1803static struct auth_ops svcauthops_gss = {
1804 .name = "rpcsec_gss",
1805 .owner = THIS_MODULE,
1806 .flavour = RPC_AUTH_GSS,
1807 .accept = svcauth_gss_accept,
1808 .release = svcauth_gss_release,
1809 .domain_release = svcauth_gss_domain_release,
1810 .set_client = svcauth_gss_set_client,
1811};
1812
1813static int rsi_cache_create_net(struct net *net)
1814{
1815 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1816 struct cache_detail *cd;
1817 int err;
1818
1819 cd = cache_create_net(&rsi_cache_template, net);
1820 if (IS_ERR(cd))
1821 return PTR_ERR(cd);
1822 err = cache_register_net(cd, net);
1823 if (err) {
1824 cache_destroy_net(cd, net);
1825 return err;
1826 }
1827 sn->rsi_cache = cd;
1828 return 0;
1829}
1830
1831static void rsi_cache_destroy_net(struct net *net)
1832{
1833 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1834 struct cache_detail *cd = sn->rsi_cache;
1835
1836 sn->rsi_cache = NULL;
1837 cache_purge(cd);
1838 cache_unregister_net(cd, net);
1839 cache_destroy_net(cd, net);
1840}
1841
1842static int rsc_cache_create_net(struct net *net)
1843{
1844 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1845 struct cache_detail *cd;
1846 int err;
1847
1848 cd = cache_create_net(&rsc_cache_template, net);
1849 if (IS_ERR(cd))
1850 return PTR_ERR(cd);
1851 err = cache_register_net(cd, net);
1852 if (err) {
1853 cache_destroy_net(cd, net);
1854 return err;
1855 }
1856 sn->rsc_cache = cd;
1857 return 0;
1858}
1859
1860static void rsc_cache_destroy_net(struct net *net)
1861{
1862 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1863 struct cache_detail *cd = sn->rsc_cache;
1864
1865 sn->rsc_cache = NULL;
1866 cache_purge(cd);
1867 cache_unregister_net(cd, net);
1868 cache_destroy_net(cd, net);
1869}
1870
1871int
1872gss_svc_init_net(struct net *net)
1873{
1874 int rv;
1875
1876 rv = rsc_cache_create_net(net);
1877 if (rv)
1878 return rv;
1879 rv = rsi_cache_create_net(net);
1880 if (rv)
1881 goto out1;
1882 rv = create_use_gss_proxy_proc_entry(net);
1883 if (rv)
1884 goto out2;
1885 return 0;
1886out2:
1887 destroy_use_gss_proxy_proc_entry(net);
1888out1:
1889 rsc_cache_destroy_net(net);
1890 return rv;
1891}
1892
1893void
1894gss_svc_shutdown_net(struct net *net)
1895{
1896 destroy_use_gss_proxy_proc_entry(net);
1897 rsi_cache_destroy_net(net);
1898 rsc_cache_destroy_net(net);
1899}
1900
1901int
1902gss_svc_init(void)
1903{
1904 return svc_auth_register(RPC_AUTH_GSS, &svcauthops_gss);
1905}
1906
1907void
1908gss_svc_shutdown(void)
1909{
1910 svc_auth_unregister(RPC_AUTH_GSS);
1911}
1/*
2 * Neil Brown <neilb@cse.unsw.edu.au>
3 * J. Bruce Fields <bfields@umich.edu>
4 * Andy Adamson <andros@umich.edu>
5 * Dug Song <dugsong@monkey.org>
6 *
7 * RPCSEC_GSS server authentication.
8 * This implements RPCSEC_GSS as defined in rfc2203 (rpcsec_gss) and rfc2078
9 * (gssapi)
10 *
11 * The RPCSEC_GSS involves three stages:
12 * 1/ context creation
13 * 2/ data exchange
14 * 3/ context destruction
15 *
16 * Context creation is handled largely by upcalls to user-space.
17 * In particular, GSS_Accept_sec_context is handled by an upcall
18 * Data exchange is handled entirely within the kernel
19 * In particular, GSS_GetMIC, GSS_VerifyMIC, GSS_Seal, GSS_Unseal are in-kernel.
20 * Context destruction is handled in-kernel
21 * GSS_Delete_sec_context is in-kernel
22 *
23 * Context creation is initiated by a RPCSEC_GSS_INIT request arriving.
24 * The context handle and gss_token are used as a key into the rpcsec_init cache.
25 * The content of this cache includes some of the outputs of GSS_Accept_sec_context,
26 * being major_status, minor_status, context_handle, reply_token.
27 * These are sent back to the client.
28 * Sequence window management is handled by the kernel. The window size if currently
29 * a compile time constant.
30 *
31 * When user-space is happy that a context is established, it places an entry
32 * in the rpcsec_context cache. The key for this cache is the context_handle.
33 * The content includes:
34 * uid/gidlist - for determining access rights
35 * mechanism type
36 * mechanism specific information, such as a key
37 *
38 */
39
40#include <linux/slab.h>
41#include <linux/types.h>
42#include <linux/module.h>
43#include <linux/pagemap.h>
44
45#include <linux/sunrpc/auth_gss.h>
46#include <linux/sunrpc/gss_err.h>
47#include <linux/sunrpc/svcauth.h>
48#include <linux/sunrpc/svcauth_gss.h>
49#include <linux/sunrpc/cache.h>
50
51#ifdef RPC_DEBUG
52# define RPCDBG_FACILITY RPCDBG_AUTH
53#endif
54
55/* The rpcsec_init cache is used for mapping RPCSEC_GSS_{,CONT_}INIT requests
56 * into replies.
57 *
58 * Key is context handle (\x if empty) and gss_token.
59 * Content is major_status minor_status (integers) context_handle, reply_token.
60 *
61 */
62
63static int netobj_equal(struct xdr_netobj *a, struct xdr_netobj *b)
64{
65 return a->len == b->len && 0 == memcmp(a->data, b->data, a->len);
66}
67
68#define RSI_HASHBITS 6
69#define RSI_HASHMAX (1<<RSI_HASHBITS)
70
71struct rsi {
72 struct cache_head h;
73 struct xdr_netobj in_handle, in_token;
74 struct xdr_netobj out_handle, out_token;
75 int major_status, minor_status;
76};
77
78static struct cache_head *rsi_table[RSI_HASHMAX];
79static struct cache_detail rsi_cache;
80static struct rsi *rsi_update(struct rsi *new, struct rsi *old);
81static struct rsi *rsi_lookup(struct rsi *item);
82
83static void rsi_free(struct rsi *rsii)
84{
85 kfree(rsii->in_handle.data);
86 kfree(rsii->in_token.data);
87 kfree(rsii->out_handle.data);
88 kfree(rsii->out_token.data);
89}
90
91static void rsi_put(struct kref *ref)
92{
93 struct rsi *rsii = container_of(ref, struct rsi, h.ref);
94 rsi_free(rsii);
95 kfree(rsii);
96}
97
98static inline int rsi_hash(struct rsi *item)
99{
100 return hash_mem(item->in_handle.data, item->in_handle.len, RSI_HASHBITS)
101 ^ hash_mem(item->in_token.data, item->in_token.len, RSI_HASHBITS);
102}
103
104static int rsi_match(struct cache_head *a, struct cache_head *b)
105{
106 struct rsi *item = container_of(a, struct rsi, h);
107 struct rsi *tmp = container_of(b, struct rsi, h);
108 return netobj_equal(&item->in_handle, &tmp->in_handle) &&
109 netobj_equal(&item->in_token, &tmp->in_token);
110}
111
112static int dup_to_netobj(struct xdr_netobj *dst, char *src, int len)
113{
114 dst->len = len;
115 dst->data = (len ? kmemdup(src, len, GFP_KERNEL) : NULL);
116 if (len && !dst->data)
117 return -ENOMEM;
118 return 0;
119}
120
121static inline int dup_netobj(struct xdr_netobj *dst, struct xdr_netobj *src)
122{
123 return dup_to_netobj(dst, src->data, src->len);
124}
125
126static void rsi_init(struct cache_head *cnew, struct cache_head *citem)
127{
128 struct rsi *new = container_of(cnew, struct rsi, h);
129 struct rsi *item = container_of(citem, struct rsi, h);
130
131 new->out_handle.data = NULL;
132 new->out_handle.len = 0;
133 new->out_token.data = NULL;
134 new->out_token.len = 0;
135 new->in_handle.len = item->in_handle.len;
136 item->in_handle.len = 0;
137 new->in_token.len = item->in_token.len;
138 item->in_token.len = 0;
139 new->in_handle.data = item->in_handle.data;
140 item->in_handle.data = NULL;
141 new->in_token.data = item->in_token.data;
142 item->in_token.data = NULL;
143}
144
145static void update_rsi(struct cache_head *cnew, struct cache_head *citem)
146{
147 struct rsi *new = container_of(cnew, struct rsi, h);
148 struct rsi *item = container_of(citem, struct rsi, h);
149
150 BUG_ON(new->out_handle.data || new->out_token.data);
151 new->out_handle.len = item->out_handle.len;
152 item->out_handle.len = 0;
153 new->out_token.len = item->out_token.len;
154 item->out_token.len = 0;
155 new->out_handle.data = item->out_handle.data;
156 item->out_handle.data = NULL;
157 new->out_token.data = item->out_token.data;
158 item->out_token.data = NULL;
159
160 new->major_status = item->major_status;
161 new->minor_status = item->minor_status;
162}
163
164static struct cache_head *rsi_alloc(void)
165{
166 struct rsi *rsii = kmalloc(sizeof(*rsii), GFP_KERNEL);
167 if (rsii)
168 return &rsii->h;
169 else
170 return NULL;
171}
172
173static void rsi_request(struct cache_detail *cd,
174 struct cache_head *h,
175 char **bpp, int *blen)
176{
177 struct rsi *rsii = container_of(h, struct rsi, h);
178
179 qword_addhex(bpp, blen, rsii->in_handle.data, rsii->in_handle.len);
180 qword_addhex(bpp, blen, rsii->in_token.data, rsii->in_token.len);
181 (*bpp)[-1] = '\n';
182}
183
184static int rsi_upcall(struct cache_detail *cd, struct cache_head *h)
185{
186 return sunrpc_cache_pipe_upcall(cd, h, rsi_request);
187}
188
189
190static int rsi_parse(struct cache_detail *cd,
191 char *mesg, int mlen)
192{
193 /* context token expiry major minor context token */
194 char *buf = mesg;
195 char *ep;
196 int len;
197 struct rsi rsii, *rsip = NULL;
198 time_t expiry;
199 int status = -EINVAL;
200
201 memset(&rsii, 0, sizeof(rsii));
202 /* handle */
203 len = qword_get(&mesg, buf, mlen);
204 if (len < 0)
205 goto out;
206 status = -ENOMEM;
207 if (dup_to_netobj(&rsii.in_handle, buf, len))
208 goto out;
209
210 /* token */
211 len = qword_get(&mesg, buf, mlen);
212 status = -EINVAL;
213 if (len < 0)
214 goto out;
215 status = -ENOMEM;
216 if (dup_to_netobj(&rsii.in_token, buf, len))
217 goto out;
218
219 rsip = rsi_lookup(&rsii);
220 if (!rsip)
221 goto out;
222
223 rsii.h.flags = 0;
224 /* expiry */
225 expiry = get_expiry(&mesg);
226 status = -EINVAL;
227 if (expiry == 0)
228 goto out;
229
230 /* major/minor */
231 len = qword_get(&mesg, buf, mlen);
232 if (len <= 0)
233 goto out;
234 rsii.major_status = simple_strtoul(buf, &ep, 10);
235 if (*ep)
236 goto out;
237 len = qword_get(&mesg, buf, mlen);
238 if (len <= 0)
239 goto out;
240 rsii.minor_status = simple_strtoul(buf, &ep, 10);
241 if (*ep)
242 goto out;
243
244 /* out_handle */
245 len = qword_get(&mesg, buf, mlen);
246 if (len < 0)
247 goto out;
248 status = -ENOMEM;
249 if (dup_to_netobj(&rsii.out_handle, buf, len))
250 goto out;
251
252 /* out_token */
253 len = qword_get(&mesg, buf, mlen);
254 status = -EINVAL;
255 if (len < 0)
256 goto out;
257 status = -ENOMEM;
258 if (dup_to_netobj(&rsii.out_token, buf, len))
259 goto out;
260 rsii.h.expiry_time = expiry;
261 rsip = rsi_update(&rsii, rsip);
262 status = 0;
263out:
264 rsi_free(&rsii);
265 if (rsip)
266 cache_put(&rsip->h, &rsi_cache);
267 else
268 status = -ENOMEM;
269 return status;
270}
271
272static struct cache_detail rsi_cache = {
273 .owner = THIS_MODULE,
274 .hash_size = RSI_HASHMAX,
275 .hash_table = rsi_table,
276 .name = "auth.rpcsec.init",
277 .cache_put = rsi_put,
278 .cache_upcall = rsi_upcall,
279 .cache_parse = rsi_parse,
280 .match = rsi_match,
281 .init = rsi_init,
282 .update = update_rsi,
283 .alloc = rsi_alloc,
284};
285
286static struct rsi *rsi_lookup(struct rsi *item)
287{
288 struct cache_head *ch;
289 int hash = rsi_hash(item);
290
291 ch = sunrpc_cache_lookup(&rsi_cache, &item->h, hash);
292 if (ch)
293 return container_of(ch, struct rsi, h);
294 else
295 return NULL;
296}
297
298static struct rsi *rsi_update(struct rsi *new, struct rsi *old)
299{
300 struct cache_head *ch;
301 int hash = rsi_hash(new);
302
303 ch = sunrpc_cache_update(&rsi_cache, &new->h,
304 &old->h, hash);
305 if (ch)
306 return container_of(ch, struct rsi, h);
307 else
308 return NULL;
309}
310
311
312/*
313 * The rpcsec_context cache is used to store a context that is
314 * used in data exchange.
315 * The key is a context handle. The content is:
316 * uid, gidlist, mechanism, service-set, mech-specific-data
317 */
318
319#define RSC_HASHBITS 10
320#define RSC_HASHMAX (1<<RSC_HASHBITS)
321
322#define GSS_SEQ_WIN 128
323
324struct gss_svc_seq_data {
325 /* highest seq number seen so far: */
326 int sd_max;
327 /* for i such that sd_max-GSS_SEQ_WIN < i <= sd_max, the i-th bit of
328 * sd_win is nonzero iff sequence number i has been seen already: */
329 unsigned long sd_win[GSS_SEQ_WIN/BITS_PER_LONG];
330 spinlock_t sd_lock;
331};
332
333struct rsc {
334 struct cache_head h;
335 struct xdr_netobj handle;
336 struct svc_cred cred;
337 struct gss_svc_seq_data seqdata;
338 struct gss_ctx *mechctx;
339 char *client_name;
340};
341
342static struct cache_head *rsc_table[RSC_HASHMAX];
343static struct cache_detail rsc_cache;
344static struct rsc *rsc_update(struct rsc *new, struct rsc *old);
345static struct rsc *rsc_lookup(struct rsc *item);
346
347static void rsc_free(struct rsc *rsci)
348{
349 kfree(rsci->handle.data);
350 if (rsci->mechctx)
351 gss_delete_sec_context(&rsci->mechctx);
352 if (rsci->cred.cr_group_info)
353 put_group_info(rsci->cred.cr_group_info);
354 kfree(rsci->client_name);
355}
356
357static void rsc_put(struct kref *ref)
358{
359 struct rsc *rsci = container_of(ref, struct rsc, h.ref);
360
361 rsc_free(rsci);
362 kfree(rsci);
363}
364
365static inline int
366rsc_hash(struct rsc *rsci)
367{
368 return hash_mem(rsci->handle.data, rsci->handle.len, RSC_HASHBITS);
369}
370
371static int
372rsc_match(struct cache_head *a, struct cache_head *b)
373{
374 struct rsc *new = container_of(a, struct rsc, h);
375 struct rsc *tmp = container_of(b, struct rsc, h);
376
377 return netobj_equal(&new->handle, &tmp->handle);
378}
379
380static void
381rsc_init(struct cache_head *cnew, struct cache_head *ctmp)
382{
383 struct rsc *new = container_of(cnew, struct rsc, h);
384 struct rsc *tmp = container_of(ctmp, struct rsc, h);
385
386 new->handle.len = tmp->handle.len;
387 tmp->handle.len = 0;
388 new->handle.data = tmp->handle.data;
389 tmp->handle.data = NULL;
390 new->mechctx = NULL;
391 new->cred.cr_group_info = NULL;
392 new->client_name = NULL;
393}
394
395static void
396update_rsc(struct cache_head *cnew, struct cache_head *ctmp)
397{
398 struct rsc *new = container_of(cnew, struct rsc, h);
399 struct rsc *tmp = container_of(ctmp, struct rsc, h);
400
401 new->mechctx = tmp->mechctx;
402 tmp->mechctx = NULL;
403 memset(&new->seqdata, 0, sizeof(new->seqdata));
404 spin_lock_init(&new->seqdata.sd_lock);
405 new->cred = tmp->cred;
406 tmp->cred.cr_group_info = NULL;
407 new->client_name = tmp->client_name;
408 tmp->client_name = NULL;
409}
410
411static struct cache_head *
412rsc_alloc(void)
413{
414 struct rsc *rsci = kmalloc(sizeof(*rsci), GFP_KERNEL);
415 if (rsci)
416 return &rsci->h;
417 else
418 return NULL;
419}
420
421static int rsc_parse(struct cache_detail *cd,
422 char *mesg, int mlen)
423{
424 /* contexthandle expiry [ uid gid N <n gids> mechname ...mechdata... ] */
425 char *buf = mesg;
426 int len, rv;
427 struct rsc rsci, *rscp = NULL;
428 time_t expiry;
429 int status = -EINVAL;
430 struct gss_api_mech *gm = NULL;
431
432 memset(&rsci, 0, sizeof(rsci));
433 /* context handle */
434 len = qword_get(&mesg, buf, mlen);
435 if (len < 0) goto out;
436 status = -ENOMEM;
437 if (dup_to_netobj(&rsci.handle, buf, len))
438 goto out;
439
440 rsci.h.flags = 0;
441 /* expiry */
442 expiry = get_expiry(&mesg);
443 status = -EINVAL;
444 if (expiry == 0)
445 goto out;
446
447 rscp = rsc_lookup(&rsci);
448 if (!rscp)
449 goto out;
450
451 /* uid, or NEGATIVE */
452 rv = get_int(&mesg, &rsci.cred.cr_uid);
453 if (rv == -EINVAL)
454 goto out;
455 if (rv == -ENOENT)
456 set_bit(CACHE_NEGATIVE, &rsci.h.flags);
457 else {
458 int N, i;
459
460 /* gid */
461 if (get_int(&mesg, &rsci.cred.cr_gid))
462 goto out;
463
464 /* number of additional gid's */
465 if (get_int(&mesg, &N))
466 goto out;
467 status = -ENOMEM;
468 rsci.cred.cr_group_info = groups_alloc(N);
469 if (rsci.cred.cr_group_info == NULL)
470 goto out;
471
472 /* gid's */
473 status = -EINVAL;
474 for (i=0; i<N; i++) {
475 gid_t gid;
476 if (get_int(&mesg, &gid))
477 goto out;
478 GROUP_AT(rsci.cred.cr_group_info, i) = gid;
479 }
480
481 /* mech name */
482 len = qword_get(&mesg, buf, mlen);
483 if (len < 0)
484 goto out;
485 gm = gss_mech_get_by_name(buf);
486 status = -EOPNOTSUPP;
487 if (!gm)
488 goto out;
489
490 status = -EINVAL;
491 /* mech-specific data: */
492 len = qword_get(&mesg, buf, mlen);
493 if (len < 0)
494 goto out;
495 status = gss_import_sec_context(buf, len, gm, &rsci.mechctx, GFP_KERNEL);
496 if (status)
497 goto out;
498
499 /* get client name */
500 len = qword_get(&mesg, buf, mlen);
501 if (len > 0) {
502 rsci.client_name = kstrdup(buf, GFP_KERNEL);
503 if (!rsci.client_name)
504 goto out;
505 }
506
507 }
508 rsci.h.expiry_time = expiry;
509 rscp = rsc_update(&rsci, rscp);
510 status = 0;
511out:
512 gss_mech_put(gm);
513 rsc_free(&rsci);
514 if (rscp)
515 cache_put(&rscp->h, &rsc_cache);
516 else
517 status = -ENOMEM;
518 return status;
519}
520
521static struct cache_detail rsc_cache = {
522 .owner = THIS_MODULE,
523 .hash_size = RSC_HASHMAX,
524 .hash_table = rsc_table,
525 .name = "auth.rpcsec.context",
526 .cache_put = rsc_put,
527 .cache_parse = rsc_parse,
528 .match = rsc_match,
529 .init = rsc_init,
530 .update = update_rsc,
531 .alloc = rsc_alloc,
532};
533
534static struct rsc *rsc_lookup(struct rsc *item)
535{
536 struct cache_head *ch;
537 int hash = rsc_hash(item);
538
539 ch = sunrpc_cache_lookup(&rsc_cache, &item->h, hash);
540 if (ch)
541 return container_of(ch, struct rsc, h);
542 else
543 return NULL;
544}
545
546static struct rsc *rsc_update(struct rsc *new, struct rsc *old)
547{
548 struct cache_head *ch;
549 int hash = rsc_hash(new);
550
551 ch = sunrpc_cache_update(&rsc_cache, &new->h,
552 &old->h, hash);
553 if (ch)
554 return container_of(ch, struct rsc, h);
555 else
556 return NULL;
557}
558
559
560static struct rsc *
561gss_svc_searchbyctx(struct xdr_netobj *handle)
562{
563 struct rsc rsci;
564 struct rsc *found;
565
566 memset(&rsci, 0, sizeof(rsci));
567 if (dup_to_netobj(&rsci.handle, handle->data, handle->len))
568 return NULL;
569 found = rsc_lookup(&rsci);
570 rsc_free(&rsci);
571 if (!found)
572 return NULL;
573 if (cache_check(&rsc_cache, &found->h, NULL))
574 return NULL;
575 return found;
576}
577
578/* Implements sequence number algorithm as specified in RFC 2203. */
579static int
580gss_check_seq_num(struct rsc *rsci, int seq_num)
581{
582 struct gss_svc_seq_data *sd = &rsci->seqdata;
583
584 spin_lock(&sd->sd_lock);
585 if (seq_num > sd->sd_max) {
586 if (seq_num >= sd->sd_max + GSS_SEQ_WIN) {
587 memset(sd->sd_win,0,sizeof(sd->sd_win));
588 sd->sd_max = seq_num;
589 } else while (sd->sd_max < seq_num) {
590 sd->sd_max++;
591 __clear_bit(sd->sd_max % GSS_SEQ_WIN, sd->sd_win);
592 }
593 __set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win);
594 goto ok;
595 } else if (seq_num <= sd->sd_max - GSS_SEQ_WIN) {
596 goto drop;
597 }
598 /* sd_max - GSS_SEQ_WIN < seq_num <= sd_max */
599 if (__test_and_set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win))
600 goto drop;
601ok:
602 spin_unlock(&sd->sd_lock);
603 return 1;
604drop:
605 spin_unlock(&sd->sd_lock);
606 return 0;
607}
608
609static inline u32 round_up_to_quad(u32 i)
610{
611 return (i + 3 ) & ~3;
612}
613
614static inline int
615svc_safe_getnetobj(struct kvec *argv, struct xdr_netobj *o)
616{
617 int l;
618
619 if (argv->iov_len < 4)
620 return -1;
621 o->len = svc_getnl(argv);
622 l = round_up_to_quad(o->len);
623 if (argv->iov_len < l)
624 return -1;
625 o->data = argv->iov_base;
626 argv->iov_base += l;
627 argv->iov_len -= l;
628 return 0;
629}
630
631static inline int
632svc_safe_putnetobj(struct kvec *resv, struct xdr_netobj *o)
633{
634 u8 *p;
635
636 if (resv->iov_len + 4 > PAGE_SIZE)
637 return -1;
638 svc_putnl(resv, o->len);
639 p = resv->iov_base + resv->iov_len;
640 resv->iov_len += round_up_to_quad(o->len);
641 if (resv->iov_len > PAGE_SIZE)
642 return -1;
643 memcpy(p, o->data, o->len);
644 memset(p + o->len, 0, round_up_to_quad(o->len) - o->len);
645 return 0;
646}
647
648/*
649 * Verify the checksum on the header and return SVC_OK on success.
650 * Otherwise, return SVC_DROP (in the case of a bad sequence number)
651 * or return SVC_DENIED and indicate error in authp.
652 */
653static int
654gss_verify_header(struct svc_rqst *rqstp, struct rsc *rsci,
655 __be32 *rpcstart, struct rpc_gss_wire_cred *gc, __be32 *authp)
656{
657 struct gss_ctx *ctx_id = rsci->mechctx;
658 struct xdr_buf rpchdr;
659 struct xdr_netobj checksum;
660 u32 flavor = 0;
661 struct kvec *argv = &rqstp->rq_arg.head[0];
662 struct kvec iov;
663
664 /* data to compute the checksum over: */
665 iov.iov_base = rpcstart;
666 iov.iov_len = (u8 *)argv->iov_base - (u8 *)rpcstart;
667 xdr_buf_from_iov(&iov, &rpchdr);
668
669 *authp = rpc_autherr_badverf;
670 if (argv->iov_len < 4)
671 return SVC_DENIED;
672 flavor = svc_getnl(argv);
673 if (flavor != RPC_AUTH_GSS)
674 return SVC_DENIED;
675 if (svc_safe_getnetobj(argv, &checksum))
676 return SVC_DENIED;
677
678 if (rqstp->rq_deferred) /* skip verification of revisited request */
679 return SVC_OK;
680 if (gss_verify_mic(ctx_id, &rpchdr, &checksum) != GSS_S_COMPLETE) {
681 *authp = rpcsec_gsserr_credproblem;
682 return SVC_DENIED;
683 }
684
685 if (gc->gc_seq > MAXSEQ) {
686 dprintk("RPC: svcauth_gss: discarding request with "
687 "large sequence number %d\n", gc->gc_seq);
688 *authp = rpcsec_gsserr_ctxproblem;
689 return SVC_DENIED;
690 }
691 if (!gss_check_seq_num(rsci, gc->gc_seq)) {
692 dprintk("RPC: svcauth_gss: discarding request with "
693 "old sequence number %d\n", gc->gc_seq);
694 return SVC_DROP;
695 }
696 return SVC_OK;
697}
698
699static int
700gss_write_null_verf(struct svc_rqst *rqstp)
701{
702 __be32 *p;
703
704 svc_putnl(rqstp->rq_res.head, RPC_AUTH_NULL);
705 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len;
706 /* don't really need to check if head->iov_len > PAGE_SIZE ... */
707 *p++ = 0;
708 if (!xdr_ressize_check(rqstp, p))
709 return -1;
710 return 0;
711}
712
713static int
714gss_write_verf(struct svc_rqst *rqstp, struct gss_ctx *ctx_id, u32 seq)
715{
716 __be32 xdr_seq;
717 u32 maj_stat;
718 struct xdr_buf verf_data;
719 struct xdr_netobj mic;
720 __be32 *p;
721 struct kvec iov;
722
723 svc_putnl(rqstp->rq_res.head, RPC_AUTH_GSS);
724 xdr_seq = htonl(seq);
725
726 iov.iov_base = &xdr_seq;
727 iov.iov_len = sizeof(xdr_seq);
728 xdr_buf_from_iov(&iov, &verf_data);
729 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len;
730 mic.data = (u8 *)(p + 1);
731 maj_stat = gss_get_mic(ctx_id, &verf_data, &mic);
732 if (maj_stat != GSS_S_COMPLETE)
733 return -1;
734 *p++ = htonl(mic.len);
735 memset((u8 *)p + mic.len, 0, round_up_to_quad(mic.len) - mic.len);
736 p += XDR_QUADLEN(mic.len);
737 if (!xdr_ressize_check(rqstp, p))
738 return -1;
739 return 0;
740}
741
742struct gss_domain {
743 struct auth_domain h;
744 u32 pseudoflavor;
745};
746
747static struct auth_domain *
748find_gss_auth_domain(struct gss_ctx *ctx, u32 svc)
749{
750 char *name;
751
752 name = gss_service_to_auth_domain_name(ctx->mech_type, svc);
753 if (!name)
754 return NULL;
755 return auth_domain_find(name);
756}
757
758static struct auth_ops svcauthops_gss;
759
760u32 svcauth_gss_flavor(struct auth_domain *dom)
761{
762 struct gss_domain *gd = container_of(dom, struct gss_domain, h);
763
764 return gd->pseudoflavor;
765}
766
767EXPORT_SYMBOL_GPL(svcauth_gss_flavor);
768
769int
770svcauth_gss_register_pseudoflavor(u32 pseudoflavor, char * name)
771{
772 struct gss_domain *new;
773 struct auth_domain *test;
774 int stat = -ENOMEM;
775
776 new = kmalloc(sizeof(*new), GFP_KERNEL);
777 if (!new)
778 goto out;
779 kref_init(&new->h.ref);
780 new->h.name = kstrdup(name, GFP_KERNEL);
781 if (!new->h.name)
782 goto out_free_dom;
783 new->h.flavour = &svcauthops_gss;
784 new->pseudoflavor = pseudoflavor;
785
786 stat = 0;
787 test = auth_domain_lookup(name, &new->h);
788 if (test != &new->h) { /* Duplicate registration */
789 auth_domain_put(test);
790 kfree(new->h.name);
791 goto out_free_dom;
792 }
793 return 0;
794
795out_free_dom:
796 kfree(new);
797out:
798 return stat;
799}
800
801EXPORT_SYMBOL_GPL(svcauth_gss_register_pseudoflavor);
802
803static inline int
804read_u32_from_xdr_buf(struct xdr_buf *buf, int base, u32 *obj)
805{
806 __be32 raw;
807 int status;
808
809 status = read_bytes_from_xdr_buf(buf, base, &raw, sizeof(*obj));
810 if (status)
811 return status;
812 *obj = ntohl(raw);
813 return 0;
814}
815
816/* It would be nice if this bit of code could be shared with the client.
817 * Obstacles:
818 * The client shouldn't malloc(), would have to pass in own memory.
819 * The server uses base of head iovec as read pointer, while the
820 * client uses separate pointer. */
821static int
822unwrap_integ_data(struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx)
823{
824 int stat = -EINVAL;
825 u32 integ_len, maj_stat;
826 struct xdr_netobj mic;
827 struct xdr_buf integ_buf;
828
829 integ_len = svc_getnl(&buf->head[0]);
830 if (integ_len & 3)
831 return stat;
832 if (integ_len > buf->len)
833 return stat;
834 if (xdr_buf_subsegment(buf, &integ_buf, 0, integ_len))
835 BUG();
836 /* copy out mic... */
837 if (read_u32_from_xdr_buf(buf, integ_len, &mic.len))
838 BUG();
839 if (mic.len > RPC_MAX_AUTH_SIZE)
840 return stat;
841 mic.data = kmalloc(mic.len, GFP_KERNEL);
842 if (!mic.data)
843 return stat;
844 if (read_bytes_from_xdr_buf(buf, integ_len + 4, mic.data, mic.len))
845 goto out;
846 maj_stat = gss_verify_mic(ctx, &integ_buf, &mic);
847 if (maj_stat != GSS_S_COMPLETE)
848 goto out;
849 if (svc_getnl(&buf->head[0]) != seq)
850 goto out;
851 stat = 0;
852out:
853 kfree(mic.data);
854 return stat;
855}
856
857static inline int
858total_buf_len(struct xdr_buf *buf)
859{
860 return buf->head[0].iov_len + buf->page_len + buf->tail[0].iov_len;
861}
862
863static void
864fix_priv_head(struct xdr_buf *buf, int pad)
865{
866 if (buf->page_len == 0) {
867 /* We need to adjust head and buf->len in tandem in this
868 * case to make svc_defer() work--it finds the original
869 * buffer start using buf->len - buf->head[0].iov_len. */
870 buf->head[0].iov_len -= pad;
871 }
872}
873
874static int
875unwrap_priv_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx)
876{
877 u32 priv_len, maj_stat;
878 int pad, saved_len, remaining_len, offset;
879
880 rqstp->rq_splice_ok = 0;
881
882 priv_len = svc_getnl(&buf->head[0]);
883 if (rqstp->rq_deferred) {
884 /* Already decrypted last time through! The sequence number
885 * check at out_seq is unnecessary but harmless: */
886 goto out_seq;
887 }
888 /* buf->len is the number of bytes from the original start of the
889 * request to the end, where head[0].iov_len is just the bytes
890 * not yet read from the head, so these two values are different: */
891 remaining_len = total_buf_len(buf);
892 if (priv_len > remaining_len)
893 return -EINVAL;
894 pad = remaining_len - priv_len;
895 buf->len -= pad;
896 fix_priv_head(buf, pad);
897
898 /* Maybe it would be better to give gss_unwrap a length parameter: */
899 saved_len = buf->len;
900 buf->len = priv_len;
901 maj_stat = gss_unwrap(ctx, 0, buf);
902 pad = priv_len - buf->len;
903 buf->len = saved_len;
904 buf->len -= pad;
905 /* The upper layers assume the buffer is aligned on 4-byte boundaries.
906 * In the krb5p case, at least, the data ends up offset, so we need to
907 * move it around. */
908 /* XXX: This is very inefficient. It would be better to either do
909 * this while we encrypt, or maybe in the receive code, if we can peak
910 * ahead and work out the service and mechanism there. */
911 offset = buf->head[0].iov_len % 4;
912 if (offset) {
913 buf->buflen = RPCSVC_MAXPAYLOAD;
914 xdr_shift_buf(buf, offset);
915 fix_priv_head(buf, pad);
916 }
917 if (maj_stat != GSS_S_COMPLETE)
918 return -EINVAL;
919out_seq:
920 if (svc_getnl(&buf->head[0]) != seq)
921 return -EINVAL;
922 return 0;
923}
924
925struct gss_svc_data {
926 /* decoded gss client cred: */
927 struct rpc_gss_wire_cred clcred;
928 /* save a pointer to the beginning of the encoded verifier,
929 * for use in encryption/checksumming in svcauth_gss_release: */
930 __be32 *verf_start;
931 struct rsc *rsci;
932};
933
934char *svc_gss_principal(struct svc_rqst *rqstp)
935{
936 struct gss_svc_data *gd = (struct gss_svc_data *)rqstp->rq_auth_data;
937
938 if (gd && gd->rsci)
939 return gd->rsci->client_name;
940 return NULL;
941}
942EXPORT_SYMBOL_GPL(svc_gss_principal);
943
944static int
945svcauth_gss_set_client(struct svc_rqst *rqstp)
946{
947 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
948 struct rsc *rsci = svcdata->rsci;
949 struct rpc_gss_wire_cred *gc = &svcdata->clcred;
950 int stat;
951
952 /*
953 * A gss export can be specified either by:
954 * export *(sec=krb5,rw)
955 * or by
956 * export gss/krb5(rw)
957 * The latter is deprecated; but for backwards compatibility reasons
958 * the nfsd code will still fall back on trying it if the former
959 * doesn't work; so we try to make both available to nfsd, below.
960 */
961 rqstp->rq_gssclient = find_gss_auth_domain(rsci->mechctx, gc->gc_svc);
962 if (rqstp->rq_gssclient == NULL)
963 return SVC_DENIED;
964 stat = svcauth_unix_set_client(rqstp);
965 if (stat == SVC_DROP || stat == SVC_CLOSE)
966 return stat;
967 return SVC_OK;
968}
969
970static inline int
971gss_write_init_verf(struct svc_rqst *rqstp, struct rsi *rsip)
972{
973 struct rsc *rsci;
974 int rc;
975
976 if (rsip->major_status != GSS_S_COMPLETE)
977 return gss_write_null_verf(rqstp);
978 rsci = gss_svc_searchbyctx(&rsip->out_handle);
979 if (rsci == NULL) {
980 rsip->major_status = GSS_S_NO_CONTEXT;
981 return gss_write_null_verf(rqstp);
982 }
983 rc = gss_write_verf(rqstp, rsci->mechctx, GSS_SEQ_WIN);
984 cache_put(&rsci->h, &rsc_cache);
985 return rc;
986}
987
988/*
989 * Having read the cred already and found we're in the context
990 * initiation case, read the verifier and initiate (or check the results
991 * of) upcalls to userspace for help with context initiation. If
992 * the upcall results are available, write the verifier and result.
993 * Otherwise, drop the request pending an answer to the upcall.
994 */
995static int svcauth_gss_handle_init(struct svc_rqst *rqstp,
996 struct rpc_gss_wire_cred *gc, __be32 *authp)
997{
998 struct kvec *argv = &rqstp->rq_arg.head[0];
999 struct kvec *resv = &rqstp->rq_res.head[0];
1000 struct xdr_netobj tmpobj;
1001 struct rsi *rsip, rsikey;
1002 int ret;
1003
1004 /* Read the verifier; should be NULL: */
1005 *authp = rpc_autherr_badverf;
1006 if (argv->iov_len < 2 * 4)
1007 return SVC_DENIED;
1008 if (svc_getnl(argv) != RPC_AUTH_NULL)
1009 return SVC_DENIED;
1010 if (svc_getnl(argv) != 0)
1011 return SVC_DENIED;
1012
1013 /* Martial context handle and token for upcall: */
1014 *authp = rpc_autherr_badcred;
1015 if (gc->gc_proc == RPC_GSS_PROC_INIT && gc->gc_ctx.len != 0)
1016 return SVC_DENIED;
1017 memset(&rsikey, 0, sizeof(rsikey));
1018 if (dup_netobj(&rsikey.in_handle, &gc->gc_ctx))
1019 return SVC_CLOSE;
1020 *authp = rpc_autherr_badverf;
1021 if (svc_safe_getnetobj(argv, &tmpobj)) {
1022 kfree(rsikey.in_handle.data);
1023 return SVC_DENIED;
1024 }
1025 if (dup_netobj(&rsikey.in_token, &tmpobj)) {
1026 kfree(rsikey.in_handle.data);
1027 return SVC_CLOSE;
1028 }
1029
1030 /* Perform upcall, or find upcall result: */
1031 rsip = rsi_lookup(&rsikey);
1032 rsi_free(&rsikey);
1033 if (!rsip)
1034 return SVC_CLOSE;
1035 if (cache_check(&rsi_cache, &rsip->h, &rqstp->rq_chandle) < 0)
1036 /* No upcall result: */
1037 return SVC_CLOSE;
1038
1039 ret = SVC_CLOSE;
1040 /* Got an answer to the upcall; use it: */
1041 if (gss_write_init_verf(rqstp, rsip))
1042 goto out;
1043 if (resv->iov_len + 4 > PAGE_SIZE)
1044 goto out;
1045 svc_putnl(resv, RPC_SUCCESS);
1046 if (svc_safe_putnetobj(resv, &rsip->out_handle))
1047 goto out;
1048 if (resv->iov_len + 3 * 4 > PAGE_SIZE)
1049 goto out;
1050 svc_putnl(resv, rsip->major_status);
1051 svc_putnl(resv, rsip->minor_status);
1052 svc_putnl(resv, GSS_SEQ_WIN);
1053 if (svc_safe_putnetobj(resv, &rsip->out_token))
1054 goto out;
1055
1056 ret = SVC_COMPLETE;
1057out:
1058 cache_put(&rsip->h, &rsi_cache);
1059 return ret;
1060}
1061
1062/*
1063 * Accept an rpcsec packet.
1064 * If context establishment, punt to user space
1065 * If data exchange, verify/decrypt
1066 * If context destruction, handle here
1067 * In the context establishment and destruction case we encode
1068 * response here and return SVC_COMPLETE.
1069 */
1070static int
1071svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
1072{
1073 struct kvec *argv = &rqstp->rq_arg.head[0];
1074 struct kvec *resv = &rqstp->rq_res.head[0];
1075 u32 crlen;
1076 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
1077 struct rpc_gss_wire_cred *gc;
1078 struct rsc *rsci = NULL;
1079 __be32 *rpcstart;
1080 __be32 *reject_stat = resv->iov_base + resv->iov_len;
1081 int ret;
1082
1083 dprintk("RPC: svcauth_gss: argv->iov_len = %zd\n",
1084 argv->iov_len);
1085
1086 *authp = rpc_autherr_badcred;
1087 if (!svcdata)
1088 svcdata = kmalloc(sizeof(*svcdata), GFP_KERNEL);
1089 if (!svcdata)
1090 goto auth_err;
1091 rqstp->rq_auth_data = svcdata;
1092 svcdata->verf_start = NULL;
1093 svcdata->rsci = NULL;
1094 gc = &svcdata->clcred;
1095
1096 /* start of rpc packet is 7 u32's back from here:
1097 * xid direction rpcversion prog vers proc flavour
1098 */
1099 rpcstart = argv->iov_base;
1100 rpcstart -= 7;
1101
1102 /* credential is:
1103 * version(==1), proc(0,1,2,3), seq, service (1,2,3), handle
1104 * at least 5 u32s, and is preceded by length, so that makes 6.
1105 */
1106
1107 if (argv->iov_len < 5 * 4)
1108 goto auth_err;
1109 crlen = svc_getnl(argv);
1110 if (svc_getnl(argv) != RPC_GSS_VERSION)
1111 goto auth_err;
1112 gc->gc_proc = svc_getnl(argv);
1113 gc->gc_seq = svc_getnl(argv);
1114 gc->gc_svc = svc_getnl(argv);
1115 if (svc_safe_getnetobj(argv, &gc->gc_ctx))
1116 goto auth_err;
1117 if (crlen != round_up_to_quad(gc->gc_ctx.len) + 5 * 4)
1118 goto auth_err;
1119
1120 if ((gc->gc_proc != RPC_GSS_PROC_DATA) && (rqstp->rq_proc != 0))
1121 goto auth_err;
1122
1123 *authp = rpc_autherr_badverf;
1124 switch (gc->gc_proc) {
1125 case RPC_GSS_PROC_INIT:
1126 case RPC_GSS_PROC_CONTINUE_INIT:
1127 return svcauth_gss_handle_init(rqstp, gc, authp);
1128 case RPC_GSS_PROC_DATA:
1129 case RPC_GSS_PROC_DESTROY:
1130 /* Look up the context, and check the verifier: */
1131 *authp = rpcsec_gsserr_credproblem;
1132 rsci = gss_svc_searchbyctx(&gc->gc_ctx);
1133 if (!rsci)
1134 goto auth_err;
1135 switch (gss_verify_header(rqstp, rsci, rpcstart, gc, authp)) {
1136 case SVC_OK:
1137 break;
1138 case SVC_DENIED:
1139 goto auth_err;
1140 case SVC_DROP:
1141 goto drop;
1142 }
1143 break;
1144 default:
1145 *authp = rpc_autherr_rejectedcred;
1146 goto auth_err;
1147 }
1148
1149 /* now act upon the command: */
1150 switch (gc->gc_proc) {
1151 case RPC_GSS_PROC_DESTROY:
1152 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
1153 goto auth_err;
1154 rsci->h.expiry_time = get_seconds();
1155 set_bit(CACHE_NEGATIVE, &rsci->h.flags);
1156 if (resv->iov_len + 4 > PAGE_SIZE)
1157 goto drop;
1158 svc_putnl(resv, RPC_SUCCESS);
1159 goto complete;
1160 case RPC_GSS_PROC_DATA:
1161 *authp = rpcsec_gsserr_ctxproblem;
1162 svcdata->verf_start = resv->iov_base + resv->iov_len;
1163 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
1164 goto auth_err;
1165 rqstp->rq_cred = rsci->cred;
1166 get_group_info(rsci->cred.cr_group_info);
1167 *authp = rpc_autherr_badcred;
1168 switch (gc->gc_svc) {
1169 case RPC_GSS_SVC_NONE:
1170 break;
1171 case RPC_GSS_SVC_INTEGRITY:
1172 /* placeholders for length and seq. number: */
1173 svc_putnl(resv, 0);
1174 svc_putnl(resv, 0);
1175 if (unwrap_integ_data(&rqstp->rq_arg,
1176 gc->gc_seq, rsci->mechctx))
1177 goto garbage_args;
1178 break;
1179 case RPC_GSS_SVC_PRIVACY:
1180 /* placeholders for length and seq. number: */
1181 svc_putnl(resv, 0);
1182 svc_putnl(resv, 0);
1183 if (unwrap_priv_data(rqstp, &rqstp->rq_arg,
1184 gc->gc_seq, rsci->mechctx))
1185 goto garbage_args;
1186 break;
1187 default:
1188 goto auth_err;
1189 }
1190 svcdata->rsci = rsci;
1191 cache_get(&rsci->h);
1192 rqstp->rq_flavor = gss_svc_to_pseudoflavor(
1193 rsci->mechctx->mech_type, gc->gc_svc);
1194 ret = SVC_OK;
1195 goto out;
1196 }
1197garbage_args:
1198 ret = SVC_GARBAGE;
1199 goto out;
1200auth_err:
1201 /* Restore write pointer to its original value: */
1202 xdr_ressize_check(rqstp, reject_stat);
1203 ret = SVC_DENIED;
1204 goto out;
1205complete:
1206 ret = SVC_COMPLETE;
1207 goto out;
1208drop:
1209 ret = SVC_DROP;
1210out:
1211 if (rsci)
1212 cache_put(&rsci->h, &rsc_cache);
1213 return ret;
1214}
1215
1216static __be32 *
1217svcauth_gss_prepare_to_wrap(struct xdr_buf *resbuf, struct gss_svc_data *gsd)
1218{
1219 __be32 *p;
1220 u32 verf_len;
1221
1222 p = gsd->verf_start;
1223 gsd->verf_start = NULL;
1224
1225 /* If the reply stat is nonzero, don't wrap: */
1226 if (*(p-1) != rpc_success)
1227 return NULL;
1228 /* Skip the verifier: */
1229 p += 1;
1230 verf_len = ntohl(*p++);
1231 p += XDR_QUADLEN(verf_len);
1232 /* move accept_stat to right place: */
1233 memcpy(p, p + 2, 4);
1234 /* Also don't wrap if the accept stat is nonzero: */
1235 if (*p != rpc_success) {
1236 resbuf->head[0].iov_len -= 2 * 4;
1237 return NULL;
1238 }
1239 p++;
1240 return p;
1241}
1242
1243static inline int
1244svcauth_gss_wrap_resp_integ(struct svc_rqst *rqstp)
1245{
1246 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1247 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1248 struct xdr_buf *resbuf = &rqstp->rq_res;
1249 struct xdr_buf integ_buf;
1250 struct xdr_netobj mic;
1251 struct kvec *resv;
1252 __be32 *p;
1253 int integ_offset, integ_len;
1254 int stat = -EINVAL;
1255
1256 p = svcauth_gss_prepare_to_wrap(resbuf, gsd);
1257 if (p == NULL)
1258 goto out;
1259 integ_offset = (u8 *)(p + 1) - (u8 *)resbuf->head[0].iov_base;
1260 integ_len = resbuf->len - integ_offset;
1261 BUG_ON(integ_len % 4);
1262 *p++ = htonl(integ_len);
1263 *p++ = htonl(gc->gc_seq);
1264 if (xdr_buf_subsegment(resbuf, &integ_buf, integ_offset,
1265 integ_len))
1266 BUG();
1267 if (resbuf->tail[0].iov_base == NULL) {
1268 if (resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1269 goto out_err;
1270 resbuf->tail[0].iov_base = resbuf->head[0].iov_base
1271 + resbuf->head[0].iov_len;
1272 resbuf->tail[0].iov_len = 0;
1273 resv = &resbuf->tail[0];
1274 } else {
1275 resv = &resbuf->tail[0];
1276 }
1277 mic.data = (u8 *)resv->iov_base + resv->iov_len + 4;
1278 if (gss_get_mic(gsd->rsci->mechctx, &integ_buf, &mic))
1279 goto out_err;
1280 svc_putnl(resv, mic.len);
1281 memset(mic.data + mic.len, 0,
1282 round_up_to_quad(mic.len) - mic.len);
1283 resv->iov_len += XDR_QUADLEN(mic.len) << 2;
1284 /* not strictly required: */
1285 resbuf->len += XDR_QUADLEN(mic.len) << 2;
1286 BUG_ON(resv->iov_len > PAGE_SIZE);
1287out:
1288 stat = 0;
1289out_err:
1290 return stat;
1291}
1292
1293static inline int
1294svcauth_gss_wrap_resp_priv(struct svc_rqst *rqstp)
1295{
1296 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1297 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1298 struct xdr_buf *resbuf = &rqstp->rq_res;
1299 struct page **inpages = NULL;
1300 __be32 *p, *len;
1301 int offset;
1302 int pad;
1303
1304 p = svcauth_gss_prepare_to_wrap(resbuf, gsd);
1305 if (p == NULL)
1306 return 0;
1307 len = p++;
1308 offset = (u8 *)p - (u8 *)resbuf->head[0].iov_base;
1309 *p++ = htonl(gc->gc_seq);
1310 inpages = resbuf->pages;
1311 /* XXX: Would be better to write some xdr helper functions for
1312 * nfs{2,3,4}xdr.c that place the data right, instead of copying: */
1313
1314 /*
1315 * If there is currently tail data, make sure there is
1316 * room for the head, tail, and 2 * RPC_MAX_AUTH_SIZE in
1317 * the page, and move the current tail data such that
1318 * there is RPC_MAX_AUTH_SIZE slack space available in
1319 * both the head and tail.
1320 */
1321 if (resbuf->tail[0].iov_base) {
1322 BUG_ON(resbuf->tail[0].iov_base >= resbuf->head[0].iov_base
1323 + PAGE_SIZE);
1324 BUG_ON(resbuf->tail[0].iov_base < resbuf->head[0].iov_base);
1325 if (resbuf->tail[0].iov_len + resbuf->head[0].iov_len
1326 + 2 * RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1327 return -ENOMEM;
1328 memmove(resbuf->tail[0].iov_base + RPC_MAX_AUTH_SIZE,
1329 resbuf->tail[0].iov_base,
1330 resbuf->tail[0].iov_len);
1331 resbuf->tail[0].iov_base += RPC_MAX_AUTH_SIZE;
1332 }
1333 /*
1334 * If there is no current tail data, make sure there is
1335 * room for the head data, and 2 * RPC_MAX_AUTH_SIZE in the
1336 * allotted page, and set up tail information such that there
1337 * is RPC_MAX_AUTH_SIZE slack space available in both the
1338 * head and tail.
1339 */
1340 if (resbuf->tail[0].iov_base == NULL) {
1341 if (resbuf->head[0].iov_len + 2*RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1342 return -ENOMEM;
1343 resbuf->tail[0].iov_base = resbuf->head[0].iov_base
1344 + resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE;
1345 resbuf->tail[0].iov_len = 0;
1346 }
1347 if (gss_wrap(gsd->rsci->mechctx, offset, resbuf, inpages))
1348 return -ENOMEM;
1349 *len = htonl(resbuf->len - offset);
1350 pad = 3 - ((resbuf->len - offset - 1)&3);
1351 p = (__be32 *)(resbuf->tail[0].iov_base + resbuf->tail[0].iov_len);
1352 memset(p, 0, pad);
1353 resbuf->tail[0].iov_len += pad;
1354 resbuf->len += pad;
1355 return 0;
1356}
1357
1358static int
1359svcauth_gss_release(struct svc_rqst *rqstp)
1360{
1361 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1362 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1363 struct xdr_buf *resbuf = &rqstp->rq_res;
1364 int stat = -EINVAL;
1365
1366 if (gc->gc_proc != RPC_GSS_PROC_DATA)
1367 goto out;
1368 /* Release can be called twice, but we only wrap once. */
1369 if (gsd->verf_start == NULL)
1370 goto out;
1371 /* normally not set till svc_send, but we need it here: */
1372 /* XXX: what for? Do we mess it up the moment we call svc_putu32
1373 * or whatever? */
1374 resbuf->len = total_buf_len(resbuf);
1375 switch (gc->gc_svc) {
1376 case RPC_GSS_SVC_NONE:
1377 break;
1378 case RPC_GSS_SVC_INTEGRITY:
1379 stat = svcauth_gss_wrap_resp_integ(rqstp);
1380 if (stat)
1381 goto out_err;
1382 break;
1383 case RPC_GSS_SVC_PRIVACY:
1384 stat = svcauth_gss_wrap_resp_priv(rqstp);
1385 if (stat)
1386 goto out_err;
1387 break;
1388 /*
1389 * For any other gc_svc value, svcauth_gss_accept() already set
1390 * the auth_error appropriately; just fall through:
1391 */
1392 }
1393
1394out:
1395 stat = 0;
1396out_err:
1397 if (rqstp->rq_client)
1398 auth_domain_put(rqstp->rq_client);
1399 rqstp->rq_client = NULL;
1400 if (rqstp->rq_gssclient)
1401 auth_domain_put(rqstp->rq_gssclient);
1402 rqstp->rq_gssclient = NULL;
1403 if (rqstp->rq_cred.cr_group_info)
1404 put_group_info(rqstp->rq_cred.cr_group_info);
1405 rqstp->rq_cred.cr_group_info = NULL;
1406 if (gsd->rsci)
1407 cache_put(&gsd->rsci->h, &rsc_cache);
1408 gsd->rsci = NULL;
1409
1410 return stat;
1411}
1412
1413static void
1414svcauth_gss_domain_release(struct auth_domain *dom)
1415{
1416 struct gss_domain *gd = container_of(dom, struct gss_domain, h);
1417
1418 kfree(dom->name);
1419 kfree(gd);
1420}
1421
1422static struct auth_ops svcauthops_gss = {
1423 .name = "rpcsec_gss",
1424 .owner = THIS_MODULE,
1425 .flavour = RPC_AUTH_GSS,
1426 .accept = svcauth_gss_accept,
1427 .release = svcauth_gss_release,
1428 .domain_release = svcauth_gss_domain_release,
1429 .set_client = svcauth_gss_set_client,
1430};
1431
1432int
1433gss_svc_init(void)
1434{
1435 int rv = svc_auth_register(RPC_AUTH_GSS, &svcauthops_gss);
1436 if (rv)
1437 return rv;
1438 rv = cache_register(&rsc_cache);
1439 if (rv)
1440 goto out1;
1441 rv = cache_register(&rsi_cache);
1442 if (rv)
1443 goto out2;
1444 return 0;
1445out2:
1446 cache_unregister(&rsc_cache);
1447out1:
1448 svc_auth_unregister(RPC_AUTH_GSS);
1449 return rv;
1450}
1451
1452void
1453gss_svc_shutdown(void)
1454{
1455 cache_unregister(&rsc_cache);
1456 cache_unregister(&rsi_cache);
1457 svc_auth_unregister(RPC_AUTH_GSS);
1458}