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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 <linux/sunrpc/gss_krb5.h>
53
54#include <trace/events/rpcgss.h>
55
56#include "gss_rpc_upcall.h"
57
58/*
59 * Unfortunately there isn't a maximum checksum size exported via the
60 * GSS API. Manufacture one based on GSS mechanisms supported by this
61 * implementation.
62 */
63#define GSS_MAX_CKSUMSIZE (GSS_KRB5_TOK_HDR_LEN + GSS_KRB5_MAX_CKSUM_LEN)
64
65/*
66 * This value may be increased in the future to accommodate other
67 * usage of the scratch buffer.
68 */
69#define GSS_SCRATCH_SIZE GSS_MAX_CKSUMSIZE
70
71struct gss_svc_data {
72 /* decoded gss client cred: */
73 struct rpc_gss_wire_cred clcred;
74 u32 gsd_databody_offset;
75 struct rsc *rsci;
76
77 /* for temporary results */
78 __be32 gsd_seq_num;
79 u8 gsd_scratch[GSS_SCRATCH_SIZE];
80};
81
82/* The rpcsec_init cache is used for mapping RPCSEC_GSS_{,CONT_}INIT requests
83 * into replies.
84 *
85 * Key is context handle (\x if empty) and gss_token.
86 * Content is major_status minor_status (integers) context_handle, reply_token.
87 *
88 */
89
90static int netobj_equal(struct xdr_netobj *a, struct xdr_netobj *b)
91{
92 return a->len == b->len && 0 == memcmp(a->data, b->data, a->len);
93}
94
95#define RSI_HASHBITS 6
96#define RSI_HASHMAX (1<<RSI_HASHBITS)
97
98struct rsi {
99 struct cache_head h;
100 struct xdr_netobj in_handle, in_token;
101 struct xdr_netobj out_handle, out_token;
102 int major_status, minor_status;
103 struct rcu_head rcu_head;
104};
105
106static struct rsi *rsi_update(struct cache_detail *cd, struct rsi *new, struct rsi *old);
107static struct rsi *rsi_lookup(struct cache_detail *cd, struct rsi *item);
108
109static void rsi_free(struct rsi *rsii)
110{
111 kfree(rsii->in_handle.data);
112 kfree(rsii->in_token.data);
113 kfree(rsii->out_handle.data);
114 kfree(rsii->out_token.data);
115}
116
117static void rsi_free_rcu(struct rcu_head *head)
118{
119 struct rsi *rsii = container_of(head, struct rsi, rcu_head);
120
121 rsi_free(rsii);
122 kfree(rsii);
123}
124
125static void rsi_put(struct kref *ref)
126{
127 struct rsi *rsii = container_of(ref, struct rsi, h.ref);
128
129 call_rcu(&rsii->rcu_head, rsi_free_rcu);
130}
131
132static inline int rsi_hash(struct rsi *item)
133{
134 return hash_mem(item->in_handle.data, item->in_handle.len, RSI_HASHBITS)
135 ^ hash_mem(item->in_token.data, item->in_token.len, RSI_HASHBITS);
136}
137
138static int rsi_match(struct cache_head *a, struct cache_head *b)
139{
140 struct rsi *item = container_of(a, struct rsi, h);
141 struct rsi *tmp = container_of(b, struct rsi, h);
142 return netobj_equal(&item->in_handle, &tmp->in_handle) &&
143 netobj_equal(&item->in_token, &tmp->in_token);
144}
145
146static int dup_to_netobj(struct xdr_netobj *dst, char *src, int len)
147{
148 dst->len = len;
149 dst->data = (len ? kmemdup(src, len, GFP_KERNEL) : NULL);
150 if (len && !dst->data)
151 return -ENOMEM;
152 return 0;
153}
154
155static inline int dup_netobj(struct xdr_netobj *dst, struct xdr_netobj *src)
156{
157 return dup_to_netobj(dst, src->data, src->len);
158}
159
160static void rsi_init(struct cache_head *cnew, struct cache_head *citem)
161{
162 struct rsi *new = container_of(cnew, struct rsi, h);
163 struct rsi *item = container_of(citem, struct rsi, h);
164
165 new->out_handle.data = NULL;
166 new->out_handle.len = 0;
167 new->out_token.data = NULL;
168 new->out_token.len = 0;
169 new->in_handle.len = item->in_handle.len;
170 item->in_handle.len = 0;
171 new->in_token.len = item->in_token.len;
172 item->in_token.len = 0;
173 new->in_handle.data = item->in_handle.data;
174 item->in_handle.data = NULL;
175 new->in_token.data = item->in_token.data;
176 item->in_token.data = NULL;
177}
178
179static void update_rsi(struct cache_head *cnew, struct cache_head *citem)
180{
181 struct rsi *new = container_of(cnew, struct rsi, h);
182 struct rsi *item = container_of(citem, struct rsi, h);
183
184 BUG_ON(new->out_handle.data || new->out_token.data);
185 new->out_handle.len = item->out_handle.len;
186 item->out_handle.len = 0;
187 new->out_token.len = item->out_token.len;
188 item->out_token.len = 0;
189 new->out_handle.data = item->out_handle.data;
190 item->out_handle.data = NULL;
191 new->out_token.data = item->out_token.data;
192 item->out_token.data = NULL;
193
194 new->major_status = item->major_status;
195 new->minor_status = item->minor_status;
196}
197
198static struct cache_head *rsi_alloc(void)
199{
200 struct rsi *rsii = kmalloc(sizeof(*rsii), GFP_KERNEL);
201 if (rsii)
202 return &rsii->h;
203 else
204 return NULL;
205}
206
207static int rsi_upcall(struct cache_detail *cd, struct cache_head *h)
208{
209 return sunrpc_cache_pipe_upcall_timeout(cd, h);
210}
211
212static void rsi_request(struct cache_detail *cd,
213 struct cache_head *h,
214 char **bpp, int *blen)
215{
216 struct rsi *rsii = container_of(h, struct rsi, h);
217
218 qword_addhex(bpp, blen, rsii->in_handle.data, rsii->in_handle.len);
219 qword_addhex(bpp, blen, rsii->in_token.data, rsii->in_token.len);
220 (*bpp)[-1] = '\n';
221 WARN_ONCE(*blen < 0,
222 "RPCSEC/GSS credential too large - please use gssproxy\n");
223}
224
225static int rsi_parse(struct cache_detail *cd,
226 char *mesg, int mlen)
227{
228 /* context token expiry major minor context token */
229 char *buf = mesg;
230 char *ep;
231 int len;
232 struct rsi rsii, *rsip = NULL;
233 time64_t expiry;
234 int status = -EINVAL;
235
236 memset(&rsii, 0, sizeof(rsii));
237 /* handle */
238 len = qword_get(&mesg, buf, mlen);
239 if (len < 0)
240 goto out;
241 status = -ENOMEM;
242 if (dup_to_netobj(&rsii.in_handle, buf, len))
243 goto out;
244
245 /* token */
246 len = qword_get(&mesg, buf, mlen);
247 status = -EINVAL;
248 if (len < 0)
249 goto out;
250 status = -ENOMEM;
251 if (dup_to_netobj(&rsii.in_token, buf, len))
252 goto out;
253
254 rsip = rsi_lookup(cd, &rsii);
255 if (!rsip)
256 goto out;
257
258 rsii.h.flags = 0;
259 /* expiry */
260 status = get_expiry(&mesg, &expiry);
261 if (status)
262 goto out;
263
264 status = -EINVAL;
265 /* major/minor */
266 len = qword_get(&mesg, buf, mlen);
267 if (len <= 0)
268 goto out;
269 rsii.major_status = simple_strtoul(buf, &ep, 10);
270 if (*ep)
271 goto out;
272 len = qword_get(&mesg, buf, mlen);
273 if (len <= 0)
274 goto out;
275 rsii.minor_status = simple_strtoul(buf, &ep, 10);
276 if (*ep)
277 goto out;
278
279 /* out_handle */
280 len = qword_get(&mesg, buf, mlen);
281 if (len < 0)
282 goto out;
283 status = -ENOMEM;
284 if (dup_to_netobj(&rsii.out_handle, buf, len))
285 goto out;
286
287 /* out_token */
288 len = qword_get(&mesg, buf, mlen);
289 status = -EINVAL;
290 if (len < 0)
291 goto out;
292 status = -ENOMEM;
293 if (dup_to_netobj(&rsii.out_token, buf, len))
294 goto out;
295 rsii.h.expiry_time = expiry;
296 rsip = rsi_update(cd, &rsii, rsip);
297 status = 0;
298out:
299 rsi_free(&rsii);
300 if (rsip)
301 cache_put(&rsip->h, cd);
302 else
303 status = -ENOMEM;
304 return status;
305}
306
307static const struct cache_detail rsi_cache_template = {
308 .owner = THIS_MODULE,
309 .hash_size = RSI_HASHMAX,
310 .name = "auth.rpcsec.init",
311 .cache_put = rsi_put,
312 .cache_upcall = rsi_upcall,
313 .cache_request = rsi_request,
314 .cache_parse = rsi_parse,
315 .match = rsi_match,
316 .init = rsi_init,
317 .update = update_rsi,
318 .alloc = rsi_alloc,
319};
320
321static struct rsi *rsi_lookup(struct cache_detail *cd, struct rsi *item)
322{
323 struct cache_head *ch;
324 int hash = rsi_hash(item);
325
326 ch = sunrpc_cache_lookup_rcu(cd, &item->h, hash);
327 if (ch)
328 return container_of(ch, struct rsi, h);
329 else
330 return NULL;
331}
332
333static struct rsi *rsi_update(struct cache_detail *cd, struct rsi *new, struct rsi *old)
334{
335 struct cache_head *ch;
336 int hash = rsi_hash(new);
337
338 ch = sunrpc_cache_update(cd, &new->h,
339 &old->h, hash);
340 if (ch)
341 return container_of(ch, struct rsi, h);
342 else
343 return NULL;
344}
345
346
347/*
348 * The rpcsec_context cache is used to store a context that is
349 * used in data exchange.
350 * The key is a context handle. The content is:
351 * uid, gidlist, mechanism, service-set, mech-specific-data
352 */
353
354#define RSC_HASHBITS 10
355#define RSC_HASHMAX (1<<RSC_HASHBITS)
356
357#define GSS_SEQ_WIN 128
358
359struct gss_svc_seq_data {
360 /* highest seq number seen so far: */
361 u32 sd_max;
362 /* for i such that sd_max-GSS_SEQ_WIN < i <= sd_max, the i-th bit of
363 * sd_win is nonzero iff sequence number i has been seen already: */
364 unsigned long sd_win[GSS_SEQ_WIN/BITS_PER_LONG];
365 spinlock_t sd_lock;
366};
367
368struct rsc {
369 struct cache_head h;
370 struct xdr_netobj handle;
371 struct svc_cred cred;
372 struct gss_svc_seq_data seqdata;
373 struct gss_ctx *mechctx;
374 struct rcu_head rcu_head;
375};
376
377static struct rsc *rsc_update(struct cache_detail *cd, struct rsc *new, struct rsc *old);
378static struct rsc *rsc_lookup(struct cache_detail *cd, struct rsc *item);
379
380static void rsc_free(struct rsc *rsci)
381{
382 kfree(rsci->handle.data);
383 if (rsci->mechctx)
384 gss_delete_sec_context(&rsci->mechctx);
385 free_svc_cred(&rsci->cred);
386}
387
388static void rsc_free_rcu(struct rcu_head *head)
389{
390 struct rsc *rsci = container_of(head, struct rsc, rcu_head);
391
392 kfree(rsci->handle.data);
393 kfree(rsci);
394}
395
396static void rsc_put(struct kref *ref)
397{
398 struct rsc *rsci = container_of(ref, struct rsc, h.ref);
399
400 if (rsci->mechctx)
401 gss_delete_sec_context(&rsci->mechctx);
402 free_svc_cred(&rsci->cred);
403 call_rcu(&rsci->rcu_head, rsc_free_rcu);
404}
405
406static inline int
407rsc_hash(struct rsc *rsci)
408{
409 return hash_mem(rsci->handle.data, rsci->handle.len, RSC_HASHBITS);
410}
411
412static int
413rsc_match(struct cache_head *a, struct cache_head *b)
414{
415 struct rsc *new = container_of(a, struct rsc, h);
416 struct rsc *tmp = container_of(b, struct rsc, h);
417
418 return netobj_equal(&new->handle, &tmp->handle);
419}
420
421static void
422rsc_init(struct cache_head *cnew, struct cache_head *ctmp)
423{
424 struct rsc *new = container_of(cnew, struct rsc, h);
425 struct rsc *tmp = container_of(ctmp, struct rsc, h);
426
427 new->handle.len = tmp->handle.len;
428 tmp->handle.len = 0;
429 new->handle.data = tmp->handle.data;
430 tmp->handle.data = NULL;
431 new->mechctx = NULL;
432 init_svc_cred(&new->cred);
433}
434
435static void
436update_rsc(struct cache_head *cnew, struct cache_head *ctmp)
437{
438 struct rsc *new = container_of(cnew, struct rsc, h);
439 struct rsc *tmp = container_of(ctmp, struct rsc, h);
440
441 new->mechctx = tmp->mechctx;
442 tmp->mechctx = NULL;
443 memset(&new->seqdata, 0, sizeof(new->seqdata));
444 spin_lock_init(&new->seqdata.sd_lock);
445 new->cred = tmp->cred;
446 init_svc_cred(&tmp->cred);
447}
448
449static struct cache_head *
450rsc_alloc(void)
451{
452 struct rsc *rsci = kmalloc(sizeof(*rsci), GFP_KERNEL);
453 if (rsci)
454 return &rsci->h;
455 else
456 return NULL;
457}
458
459static int rsc_upcall(struct cache_detail *cd, struct cache_head *h)
460{
461 return -EINVAL;
462}
463
464static int rsc_parse(struct cache_detail *cd,
465 char *mesg, int mlen)
466{
467 /* contexthandle expiry [ uid gid N <n gids> mechname ...mechdata... ] */
468 char *buf = mesg;
469 int id;
470 int len, rv;
471 struct rsc rsci, *rscp = NULL;
472 time64_t expiry;
473 int status = -EINVAL;
474 struct gss_api_mech *gm = NULL;
475
476 memset(&rsci, 0, sizeof(rsci));
477 /* context handle */
478 len = qword_get(&mesg, buf, mlen);
479 if (len < 0) goto out;
480 status = -ENOMEM;
481 if (dup_to_netobj(&rsci.handle, buf, len))
482 goto out;
483
484 rsci.h.flags = 0;
485 /* expiry */
486 status = get_expiry(&mesg, &expiry);
487 if (status)
488 goto out;
489
490 status = -EINVAL;
491 rscp = rsc_lookup(cd, &rsci);
492 if (!rscp)
493 goto out;
494
495 /* uid, or NEGATIVE */
496 rv = get_int(&mesg, &id);
497 if (rv == -EINVAL)
498 goto out;
499 if (rv == -ENOENT)
500 set_bit(CACHE_NEGATIVE, &rsci.h.flags);
501 else {
502 int N, i;
503
504 /*
505 * NOTE: we skip uid_valid()/gid_valid() checks here:
506 * instead, * -1 id's are later mapped to the
507 * (export-specific) anonymous id by nfsd_setuser.
508 *
509 * (But supplementary gid's get no such special
510 * treatment so are checked for validity here.)
511 */
512 /* uid */
513 rsci.cred.cr_uid = make_kuid(current_user_ns(), id);
514
515 /* gid */
516 if (get_int(&mesg, &id))
517 goto out;
518 rsci.cred.cr_gid = make_kgid(current_user_ns(), id);
519
520 /* number of additional gid's */
521 if (get_int(&mesg, &N))
522 goto out;
523 if (N < 0 || N > NGROUPS_MAX)
524 goto out;
525 status = -ENOMEM;
526 rsci.cred.cr_group_info = groups_alloc(N);
527 if (rsci.cred.cr_group_info == NULL)
528 goto out;
529
530 /* gid's */
531 status = -EINVAL;
532 for (i=0; i<N; i++) {
533 kgid_t kgid;
534 if (get_int(&mesg, &id))
535 goto out;
536 kgid = make_kgid(current_user_ns(), id);
537 if (!gid_valid(kgid))
538 goto out;
539 rsci.cred.cr_group_info->gid[i] = kgid;
540 }
541 groups_sort(rsci.cred.cr_group_info);
542
543 /* mech name */
544 len = qword_get(&mesg, buf, mlen);
545 if (len < 0)
546 goto out;
547 gm = rsci.cred.cr_gss_mech = gss_mech_get_by_name(buf);
548 status = -EOPNOTSUPP;
549 if (!gm)
550 goto out;
551
552 status = -EINVAL;
553 /* mech-specific data: */
554 len = qword_get(&mesg, buf, mlen);
555 if (len < 0)
556 goto out;
557 status = gss_import_sec_context(buf, len, gm, &rsci.mechctx,
558 NULL, GFP_KERNEL);
559 if (status)
560 goto out;
561
562 /* get client name */
563 len = qword_get(&mesg, buf, mlen);
564 if (len > 0) {
565 rsci.cred.cr_principal = kstrdup(buf, GFP_KERNEL);
566 if (!rsci.cred.cr_principal) {
567 status = -ENOMEM;
568 goto out;
569 }
570 }
571
572 }
573 rsci.h.expiry_time = expiry;
574 rscp = rsc_update(cd, &rsci, rscp);
575 status = 0;
576out:
577 rsc_free(&rsci);
578 if (rscp)
579 cache_put(&rscp->h, cd);
580 else
581 status = -ENOMEM;
582 return status;
583}
584
585static const struct cache_detail rsc_cache_template = {
586 .owner = THIS_MODULE,
587 .hash_size = RSC_HASHMAX,
588 .name = "auth.rpcsec.context",
589 .cache_put = rsc_put,
590 .cache_upcall = rsc_upcall,
591 .cache_parse = rsc_parse,
592 .match = rsc_match,
593 .init = rsc_init,
594 .update = update_rsc,
595 .alloc = rsc_alloc,
596};
597
598static struct rsc *rsc_lookup(struct cache_detail *cd, struct rsc *item)
599{
600 struct cache_head *ch;
601 int hash = rsc_hash(item);
602
603 ch = sunrpc_cache_lookup_rcu(cd, &item->h, hash);
604 if (ch)
605 return container_of(ch, struct rsc, h);
606 else
607 return NULL;
608}
609
610static struct rsc *rsc_update(struct cache_detail *cd, struct rsc *new, struct rsc *old)
611{
612 struct cache_head *ch;
613 int hash = rsc_hash(new);
614
615 ch = sunrpc_cache_update(cd, &new->h,
616 &old->h, hash);
617 if (ch)
618 return container_of(ch, struct rsc, h);
619 else
620 return NULL;
621}
622
623
624static struct rsc *
625gss_svc_searchbyctx(struct cache_detail *cd, struct xdr_netobj *handle)
626{
627 struct rsc rsci;
628 struct rsc *found;
629
630 memset(&rsci, 0, sizeof(rsci));
631 if (dup_to_netobj(&rsci.handle, handle->data, handle->len))
632 return NULL;
633 found = rsc_lookup(cd, &rsci);
634 rsc_free(&rsci);
635 if (!found)
636 return NULL;
637 if (cache_check(cd, &found->h, NULL))
638 return NULL;
639 return found;
640}
641
642/**
643 * gss_check_seq_num - GSS sequence number window check
644 * @rqstp: RPC Call to use when reporting errors
645 * @rsci: cached GSS context state (updated on return)
646 * @seq_num: sequence number to check
647 *
648 * Implements sequence number algorithm as specified in
649 * RFC 2203, Section 5.3.3.1. "Context Management".
650 *
651 * Return values:
652 * %true: @rqstp's GSS sequence number is inside the window
653 * %false: @rqstp's GSS sequence number is outside the window
654 */
655static bool gss_check_seq_num(const struct svc_rqst *rqstp, struct rsc *rsci,
656 u32 seq_num)
657{
658 struct gss_svc_seq_data *sd = &rsci->seqdata;
659 bool result = false;
660
661 spin_lock(&sd->sd_lock);
662 if (seq_num > sd->sd_max) {
663 if (seq_num >= sd->sd_max + GSS_SEQ_WIN) {
664 memset(sd->sd_win, 0, sizeof(sd->sd_win));
665 sd->sd_max = seq_num;
666 } else while (sd->sd_max < seq_num) {
667 sd->sd_max++;
668 __clear_bit(sd->sd_max % GSS_SEQ_WIN, sd->sd_win);
669 }
670 __set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win);
671 goto ok;
672 } else if (seq_num + GSS_SEQ_WIN <= sd->sd_max) {
673 goto toolow;
674 }
675 if (__test_and_set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win))
676 goto alreadyseen;
677
678ok:
679 result = true;
680out:
681 spin_unlock(&sd->sd_lock);
682 return result;
683
684toolow:
685 trace_rpcgss_svc_seqno_low(rqstp, seq_num,
686 sd->sd_max - GSS_SEQ_WIN,
687 sd->sd_max);
688 goto out;
689alreadyseen:
690 trace_rpcgss_svc_seqno_seen(rqstp, seq_num);
691 goto out;
692}
693
694/*
695 * Decode and verify a Call's verifier field. For RPC_AUTH_GSS Calls,
696 * the body of this field contains a variable length checksum.
697 *
698 * GSS-specific auth_stat values are mandated by RFC 2203 Section
699 * 5.3.3.3.
700 */
701static int
702svcauth_gss_verify_header(struct svc_rqst *rqstp, struct rsc *rsci,
703 __be32 *rpcstart, struct rpc_gss_wire_cred *gc)
704{
705 struct xdr_stream *xdr = &rqstp->rq_arg_stream;
706 struct gss_ctx *ctx_id = rsci->mechctx;
707 u32 flavor, maj_stat;
708 struct xdr_buf rpchdr;
709 struct xdr_netobj checksum;
710 struct kvec iov;
711
712 /*
713 * Compute the checksum of the incoming Call from the
714 * XID field to credential field:
715 */
716 iov.iov_base = rpcstart;
717 iov.iov_len = (u8 *)xdr->p - (u8 *)rpcstart;
718 xdr_buf_from_iov(&iov, &rpchdr);
719
720 /* Call's verf field: */
721 if (xdr_stream_decode_opaque_auth(xdr, &flavor,
722 (void **)&checksum.data,
723 &checksum.len) < 0) {
724 rqstp->rq_auth_stat = rpc_autherr_badverf;
725 return SVC_DENIED;
726 }
727 if (flavor != RPC_AUTH_GSS) {
728 rqstp->rq_auth_stat = rpc_autherr_badverf;
729 return SVC_DENIED;
730 }
731
732 if (rqstp->rq_deferred)
733 return SVC_OK;
734 maj_stat = gss_verify_mic(ctx_id, &rpchdr, &checksum);
735 if (maj_stat != GSS_S_COMPLETE) {
736 trace_rpcgss_svc_mic(rqstp, maj_stat);
737 rqstp->rq_auth_stat = rpcsec_gsserr_credproblem;
738 return SVC_DENIED;
739 }
740
741 if (gc->gc_seq > MAXSEQ) {
742 trace_rpcgss_svc_seqno_large(rqstp, gc->gc_seq);
743 rqstp->rq_auth_stat = rpcsec_gsserr_ctxproblem;
744 return SVC_DENIED;
745 }
746 if (!gss_check_seq_num(rqstp, rsci, gc->gc_seq))
747 return SVC_DROP;
748 return SVC_OK;
749}
750
751/*
752 * Construct and encode a Reply's verifier field. The verifier's body
753 * field contains a variable-length checksum of the GSS sequence
754 * number.
755 */
756static bool
757svcauth_gss_encode_verf(struct svc_rqst *rqstp, struct gss_ctx *ctx_id, u32 seq)
758{
759 struct gss_svc_data *gsd = rqstp->rq_auth_data;
760 u32 maj_stat;
761 struct xdr_buf verf_data;
762 struct xdr_netobj checksum;
763 struct kvec iov;
764
765 gsd->gsd_seq_num = cpu_to_be32(seq);
766 iov.iov_base = &gsd->gsd_seq_num;
767 iov.iov_len = XDR_UNIT;
768 xdr_buf_from_iov(&iov, &verf_data);
769
770 checksum.data = gsd->gsd_scratch;
771 maj_stat = gss_get_mic(ctx_id, &verf_data, &checksum);
772 if (maj_stat != GSS_S_COMPLETE)
773 goto bad_mic;
774
775 return xdr_stream_encode_opaque_auth(&rqstp->rq_res_stream, RPC_AUTH_GSS,
776 checksum.data, checksum.len) > 0;
777
778bad_mic:
779 trace_rpcgss_svc_get_mic(rqstp, maj_stat);
780 return false;
781}
782
783struct gss_domain {
784 struct auth_domain h;
785 u32 pseudoflavor;
786};
787
788static struct auth_domain *
789find_gss_auth_domain(struct gss_ctx *ctx, u32 svc)
790{
791 char *name;
792
793 name = gss_service_to_auth_domain_name(ctx->mech_type, svc);
794 if (!name)
795 return NULL;
796 return auth_domain_find(name);
797}
798
799static struct auth_ops svcauthops_gss;
800
801u32 svcauth_gss_flavor(struct auth_domain *dom)
802{
803 struct gss_domain *gd = container_of(dom, struct gss_domain, h);
804
805 return gd->pseudoflavor;
806}
807
808EXPORT_SYMBOL_GPL(svcauth_gss_flavor);
809
810struct auth_domain *
811svcauth_gss_register_pseudoflavor(u32 pseudoflavor, char * name)
812{
813 struct gss_domain *new;
814 struct auth_domain *test;
815 int stat = -ENOMEM;
816
817 new = kmalloc(sizeof(*new), GFP_KERNEL);
818 if (!new)
819 goto out;
820 kref_init(&new->h.ref);
821 new->h.name = kstrdup(name, GFP_KERNEL);
822 if (!new->h.name)
823 goto out_free_dom;
824 new->h.flavour = &svcauthops_gss;
825 new->pseudoflavor = pseudoflavor;
826
827 test = auth_domain_lookup(name, &new->h);
828 if (test != &new->h) {
829 pr_warn("svc: duplicate registration of gss pseudo flavour %s.\n",
830 name);
831 stat = -EADDRINUSE;
832 auth_domain_put(test);
833 goto out_free_name;
834 }
835 return test;
836
837out_free_name:
838 kfree(new->h.name);
839out_free_dom:
840 kfree(new);
841out:
842 return ERR_PTR(stat);
843}
844EXPORT_SYMBOL_GPL(svcauth_gss_register_pseudoflavor);
845
846/*
847 * RFC 2203, Section 5.3.2.2
848 *
849 * struct rpc_gss_integ_data {
850 * opaque databody_integ<>;
851 * opaque checksum<>;
852 * };
853 *
854 * struct rpc_gss_data_t {
855 * unsigned int seq_num;
856 * proc_req_arg_t arg;
857 * };
858 */
859static noinline_for_stack int
860svcauth_gss_unwrap_integ(struct svc_rqst *rqstp, u32 seq, struct gss_ctx *ctx)
861{
862 struct gss_svc_data *gsd = rqstp->rq_auth_data;
863 struct xdr_stream *xdr = &rqstp->rq_arg_stream;
864 u32 len, offset, seq_num, maj_stat;
865 struct xdr_buf *buf = xdr->buf;
866 struct xdr_buf databody_integ;
867 struct xdr_netobj checksum;
868
869 /* Did we already verify the signature on the original pass through? */
870 if (rqstp->rq_deferred)
871 return 0;
872
873 if (xdr_stream_decode_u32(xdr, &len) < 0)
874 goto unwrap_failed;
875 if (len & 3)
876 goto unwrap_failed;
877 offset = xdr_stream_pos(xdr);
878 if (xdr_buf_subsegment(buf, &databody_integ, offset, len))
879 goto unwrap_failed;
880
881 /*
882 * The xdr_stream now points to the @seq_num field. The next
883 * XDR data item is the @arg field, which contains the clear
884 * text RPC program payload. The checksum, which follows the
885 * @arg field, is located and decoded without updating the
886 * xdr_stream.
887 */
888
889 offset += len;
890 if (xdr_decode_word(buf, offset, &checksum.len))
891 goto unwrap_failed;
892 if (checksum.len > sizeof(gsd->gsd_scratch))
893 goto unwrap_failed;
894 checksum.data = gsd->gsd_scratch;
895 if (read_bytes_from_xdr_buf(buf, offset + XDR_UNIT, checksum.data,
896 checksum.len))
897 goto unwrap_failed;
898
899 maj_stat = gss_verify_mic(ctx, &databody_integ, &checksum);
900 if (maj_stat != GSS_S_COMPLETE)
901 goto bad_mic;
902
903 /* The received seqno is protected by the checksum. */
904 if (xdr_stream_decode_u32(xdr, &seq_num) < 0)
905 goto unwrap_failed;
906 if (seq_num != seq)
907 goto bad_seqno;
908
909 xdr_truncate_decode(xdr, XDR_UNIT + checksum.len);
910 return 0;
911
912unwrap_failed:
913 trace_rpcgss_svc_unwrap_failed(rqstp);
914 return -EINVAL;
915bad_seqno:
916 trace_rpcgss_svc_seqno_bad(rqstp, seq, seq_num);
917 return -EINVAL;
918bad_mic:
919 trace_rpcgss_svc_mic(rqstp, maj_stat);
920 return -EINVAL;
921}
922
923/*
924 * RFC 2203, Section 5.3.2.3
925 *
926 * struct rpc_gss_priv_data {
927 * opaque databody_priv<>
928 * };
929 *
930 * struct rpc_gss_data_t {
931 * unsigned int seq_num;
932 * proc_req_arg_t arg;
933 * };
934 */
935static noinline_for_stack int
936svcauth_gss_unwrap_priv(struct svc_rqst *rqstp, u32 seq, struct gss_ctx *ctx)
937{
938 struct xdr_stream *xdr = &rqstp->rq_arg_stream;
939 u32 len, maj_stat, seq_num, offset;
940 struct xdr_buf *buf = xdr->buf;
941 unsigned int saved_len;
942
943 if (xdr_stream_decode_u32(xdr, &len) < 0)
944 goto unwrap_failed;
945 if (rqstp->rq_deferred) {
946 /* Already decrypted last time through! The sequence number
947 * check at out_seq is unnecessary but harmless: */
948 goto out_seq;
949 }
950 if (len > xdr_stream_remaining(xdr))
951 goto unwrap_failed;
952 offset = xdr_stream_pos(xdr);
953
954 saved_len = buf->len;
955 maj_stat = gss_unwrap(ctx, offset, offset + len, buf);
956 if (maj_stat != GSS_S_COMPLETE)
957 goto bad_unwrap;
958 xdr->nwords -= XDR_QUADLEN(saved_len - buf->len);
959
960out_seq:
961 /* gss_unwrap() decrypted the sequence number. */
962 if (xdr_stream_decode_u32(xdr, &seq_num) < 0)
963 goto unwrap_failed;
964 if (seq_num != seq)
965 goto bad_seqno;
966 return 0;
967
968unwrap_failed:
969 trace_rpcgss_svc_unwrap_failed(rqstp);
970 return -EINVAL;
971bad_seqno:
972 trace_rpcgss_svc_seqno_bad(rqstp, seq, seq_num);
973 return -EINVAL;
974bad_unwrap:
975 trace_rpcgss_svc_unwrap(rqstp, maj_stat);
976 return -EINVAL;
977}
978
979static enum svc_auth_status
980svcauth_gss_set_client(struct svc_rqst *rqstp)
981{
982 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
983 struct rsc *rsci = svcdata->rsci;
984 struct rpc_gss_wire_cred *gc = &svcdata->clcred;
985 int stat;
986
987 rqstp->rq_auth_stat = rpc_autherr_badcred;
988
989 /*
990 * A gss export can be specified either by:
991 * export *(sec=krb5,rw)
992 * or by
993 * export gss/krb5(rw)
994 * The latter is deprecated; but for backwards compatibility reasons
995 * the nfsd code will still fall back on trying it if the former
996 * doesn't work; so we try to make both available to nfsd, below.
997 */
998 rqstp->rq_gssclient = find_gss_auth_domain(rsci->mechctx, gc->gc_svc);
999 if (rqstp->rq_gssclient == NULL)
1000 return SVC_DENIED;
1001 stat = svcauth_unix_set_client(rqstp);
1002 if (stat == SVC_DROP || stat == SVC_CLOSE)
1003 return stat;
1004
1005 rqstp->rq_auth_stat = rpc_auth_ok;
1006 return SVC_OK;
1007}
1008
1009static bool
1010svcauth_gss_proc_init_verf(struct cache_detail *cd, struct svc_rqst *rqstp,
1011 struct xdr_netobj *out_handle, int *major_status,
1012 u32 seq_num)
1013{
1014 struct xdr_stream *xdr = &rqstp->rq_res_stream;
1015 struct rsc *rsci;
1016 bool rc;
1017
1018 if (*major_status != GSS_S_COMPLETE)
1019 goto null_verifier;
1020 rsci = gss_svc_searchbyctx(cd, out_handle);
1021 if (rsci == NULL) {
1022 *major_status = GSS_S_NO_CONTEXT;
1023 goto null_verifier;
1024 }
1025
1026 rc = svcauth_gss_encode_verf(rqstp, rsci->mechctx, seq_num);
1027 cache_put(&rsci->h, cd);
1028 return rc;
1029
1030null_verifier:
1031 return xdr_stream_encode_opaque_auth(xdr, RPC_AUTH_NULL, NULL, 0) > 0;
1032}
1033
1034static void gss_free_in_token_pages(struct gssp_in_token *in_token)
1035{
1036 int i;
1037
1038 i = 0;
1039 while (in_token->pages[i])
1040 put_page(in_token->pages[i++]);
1041 kfree(in_token->pages);
1042 in_token->pages = NULL;
1043}
1044
1045static int gss_read_proxy_verf(struct svc_rqst *rqstp,
1046 struct rpc_gss_wire_cred *gc,
1047 struct xdr_netobj *in_handle,
1048 struct gssp_in_token *in_token)
1049{
1050 struct xdr_stream *xdr = &rqstp->rq_arg_stream;
1051 unsigned int length, pgto_offs, pgfrom_offs;
1052 int pages, i, pgto, pgfrom;
1053 size_t to_offs, from_offs;
1054 u32 inlen;
1055
1056 if (dup_netobj(in_handle, &gc->gc_ctx))
1057 return SVC_CLOSE;
1058
1059 /*
1060 * RFC 2203 Section 5.2.2
1061 *
1062 * struct rpc_gss_init_arg {
1063 * opaque gss_token<>;
1064 * };
1065 */
1066 if (xdr_stream_decode_u32(xdr, &inlen) < 0)
1067 goto out_denied_free;
1068 if (inlen > xdr_stream_remaining(xdr))
1069 goto out_denied_free;
1070
1071 pages = DIV_ROUND_UP(inlen, PAGE_SIZE);
1072 in_token->pages = kcalloc(pages + 1, sizeof(struct page *), GFP_KERNEL);
1073 if (!in_token->pages)
1074 goto out_denied_free;
1075 in_token->page_base = 0;
1076 in_token->page_len = inlen;
1077 for (i = 0; i < pages; i++) {
1078 in_token->pages[i] = alloc_page(GFP_KERNEL);
1079 if (!in_token->pages[i]) {
1080 gss_free_in_token_pages(in_token);
1081 goto out_denied_free;
1082 }
1083 }
1084
1085 length = min_t(unsigned int, inlen, (char *)xdr->end - (char *)xdr->p);
1086 memcpy(page_address(in_token->pages[0]), xdr->p, length);
1087 inlen -= length;
1088
1089 to_offs = length;
1090 from_offs = rqstp->rq_arg.page_base;
1091 while (inlen) {
1092 pgto = to_offs >> PAGE_SHIFT;
1093 pgfrom = from_offs >> PAGE_SHIFT;
1094 pgto_offs = to_offs & ~PAGE_MASK;
1095 pgfrom_offs = from_offs & ~PAGE_MASK;
1096
1097 length = min_t(unsigned int, inlen,
1098 min_t(unsigned int, PAGE_SIZE - pgto_offs,
1099 PAGE_SIZE - pgfrom_offs));
1100 memcpy(page_address(in_token->pages[pgto]) + pgto_offs,
1101 page_address(rqstp->rq_arg.pages[pgfrom]) + pgfrom_offs,
1102 length);
1103
1104 to_offs += length;
1105 from_offs += length;
1106 inlen -= length;
1107 }
1108 return 0;
1109
1110out_denied_free:
1111 kfree(in_handle->data);
1112 return SVC_DENIED;
1113}
1114
1115/*
1116 * RFC 2203, Section 5.2.3.1.
1117 *
1118 * struct rpc_gss_init_res {
1119 * opaque handle<>;
1120 * unsigned int gss_major;
1121 * unsigned int gss_minor;
1122 * unsigned int seq_window;
1123 * opaque gss_token<>;
1124 * };
1125 */
1126static bool
1127svcxdr_encode_gss_init_res(struct xdr_stream *xdr,
1128 struct xdr_netobj *handle,
1129 struct xdr_netobj *gss_token,
1130 unsigned int major_status,
1131 unsigned int minor_status, u32 seq_num)
1132{
1133 if (xdr_stream_encode_opaque(xdr, handle->data, handle->len) < 0)
1134 return false;
1135 if (xdr_stream_encode_u32(xdr, major_status) < 0)
1136 return false;
1137 if (xdr_stream_encode_u32(xdr, minor_status) < 0)
1138 return false;
1139 if (xdr_stream_encode_u32(xdr, seq_num) < 0)
1140 return false;
1141 if (xdr_stream_encode_opaque(xdr, gss_token->data, gss_token->len) < 0)
1142 return false;
1143 return true;
1144}
1145
1146/*
1147 * Having read the cred already and found we're in the context
1148 * initiation case, read the verifier and initiate (or check the results
1149 * of) upcalls to userspace for help with context initiation. If
1150 * the upcall results are available, write the verifier and result.
1151 * Otherwise, drop the request pending an answer to the upcall.
1152 */
1153static int
1154svcauth_gss_legacy_init(struct svc_rqst *rqstp,
1155 struct rpc_gss_wire_cred *gc)
1156{
1157 struct xdr_stream *xdr = &rqstp->rq_arg_stream;
1158 struct rsi *rsip, rsikey;
1159 __be32 *p;
1160 u32 len;
1161 int ret;
1162 struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id);
1163
1164 memset(&rsikey, 0, sizeof(rsikey));
1165 if (dup_netobj(&rsikey.in_handle, &gc->gc_ctx))
1166 return SVC_CLOSE;
1167
1168 /*
1169 * RFC 2203 Section 5.2.2
1170 *
1171 * struct rpc_gss_init_arg {
1172 * opaque gss_token<>;
1173 * };
1174 */
1175 if (xdr_stream_decode_u32(xdr, &len) < 0) {
1176 kfree(rsikey.in_handle.data);
1177 return SVC_DENIED;
1178 }
1179 p = xdr_inline_decode(xdr, len);
1180 if (!p) {
1181 kfree(rsikey.in_handle.data);
1182 return SVC_DENIED;
1183 }
1184 rsikey.in_token.data = kmalloc(len, GFP_KERNEL);
1185 if (ZERO_OR_NULL_PTR(rsikey.in_token.data)) {
1186 kfree(rsikey.in_handle.data);
1187 return SVC_CLOSE;
1188 }
1189 memcpy(rsikey.in_token.data, p, len);
1190 rsikey.in_token.len = len;
1191
1192 /* Perform upcall, or find upcall result: */
1193 rsip = rsi_lookup(sn->rsi_cache, &rsikey);
1194 rsi_free(&rsikey);
1195 if (!rsip)
1196 return SVC_CLOSE;
1197 if (cache_check(sn->rsi_cache, &rsip->h, &rqstp->rq_chandle) < 0)
1198 /* No upcall result: */
1199 return SVC_CLOSE;
1200
1201 ret = SVC_CLOSE;
1202 if (!svcauth_gss_proc_init_verf(sn->rsc_cache, rqstp, &rsip->out_handle,
1203 &rsip->major_status, GSS_SEQ_WIN))
1204 goto out;
1205 if (!svcxdr_set_accept_stat(rqstp))
1206 goto out;
1207 if (!svcxdr_encode_gss_init_res(&rqstp->rq_res_stream, &rsip->out_handle,
1208 &rsip->out_token, rsip->major_status,
1209 rsip->minor_status, GSS_SEQ_WIN))
1210 goto out;
1211
1212 ret = SVC_COMPLETE;
1213out:
1214 cache_put(&rsip->h, sn->rsi_cache);
1215 return ret;
1216}
1217
1218static int gss_proxy_save_rsc(struct cache_detail *cd,
1219 struct gssp_upcall_data *ud,
1220 uint64_t *handle)
1221{
1222 struct rsc rsci, *rscp = NULL;
1223 static atomic64_t ctxhctr;
1224 long long ctxh;
1225 struct gss_api_mech *gm = NULL;
1226 time64_t expiry;
1227 int status;
1228
1229 memset(&rsci, 0, sizeof(rsci));
1230 /* context handle */
1231 status = -ENOMEM;
1232 /* the handle needs to be just a unique id,
1233 * use a static counter */
1234 ctxh = atomic64_inc_return(&ctxhctr);
1235
1236 /* make a copy for the caller */
1237 *handle = ctxh;
1238
1239 /* make a copy for the rsc cache */
1240 if (dup_to_netobj(&rsci.handle, (char *)handle, sizeof(uint64_t)))
1241 goto out;
1242 rscp = rsc_lookup(cd, &rsci);
1243 if (!rscp)
1244 goto out;
1245
1246 /* creds */
1247 if (!ud->found_creds) {
1248 /* userspace seem buggy, we should always get at least a
1249 * mapping to nobody */
1250 goto out;
1251 } else {
1252 struct timespec64 boot;
1253
1254 /* steal creds */
1255 rsci.cred = ud->creds;
1256 memset(&ud->creds, 0, sizeof(struct svc_cred));
1257
1258 status = -EOPNOTSUPP;
1259 /* get mech handle from OID */
1260 gm = gss_mech_get_by_OID(&ud->mech_oid);
1261 if (!gm)
1262 goto out;
1263 rsci.cred.cr_gss_mech = gm;
1264
1265 status = -EINVAL;
1266 /* mech-specific data: */
1267 status = gss_import_sec_context(ud->out_handle.data,
1268 ud->out_handle.len,
1269 gm, &rsci.mechctx,
1270 &expiry, GFP_KERNEL);
1271 if (status)
1272 goto out;
1273
1274 getboottime64(&boot);
1275 expiry -= boot.tv_sec;
1276 }
1277
1278 rsci.h.expiry_time = expiry;
1279 rscp = rsc_update(cd, &rsci, rscp);
1280 status = 0;
1281out:
1282 rsc_free(&rsci);
1283 if (rscp)
1284 cache_put(&rscp->h, cd);
1285 else
1286 status = -ENOMEM;
1287 return status;
1288}
1289
1290static int svcauth_gss_proxy_init(struct svc_rqst *rqstp,
1291 struct rpc_gss_wire_cred *gc)
1292{
1293 struct xdr_netobj cli_handle;
1294 struct gssp_upcall_data ud;
1295 uint64_t handle;
1296 int status;
1297 int ret;
1298 struct net *net = SVC_NET(rqstp);
1299 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1300
1301 memset(&ud, 0, sizeof(ud));
1302 ret = gss_read_proxy_verf(rqstp, gc, &ud.in_handle, &ud.in_token);
1303 if (ret)
1304 return ret;
1305
1306 ret = SVC_CLOSE;
1307
1308 /* Perform synchronous upcall to gss-proxy */
1309 status = gssp_accept_sec_context_upcall(net, &ud);
1310 if (status)
1311 goto out;
1312
1313 trace_rpcgss_svc_accept_upcall(rqstp, ud.major_status, ud.minor_status);
1314
1315 switch (ud.major_status) {
1316 case GSS_S_CONTINUE_NEEDED:
1317 cli_handle = ud.out_handle;
1318 break;
1319 case GSS_S_COMPLETE:
1320 status = gss_proxy_save_rsc(sn->rsc_cache, &ud, &handle);
1321 if (status)
1322 goto out;
1323 cli_handle.data = (u8 *)&handle;
1324 cli_handle.len = sizeof(handle);
1325 break;
1326 default:
1327 goto out;
1328 }
1329
1330 if (!svcauth_gss_proc_init_verf(sn->rsc_cache, rqstp, &cli_handle,
1331 &ud.major_status, GSS_SEQ_WIN))
1332 goto out;
1333 if (!svcxdr_set_accept_stat(rqstp))
1334 goto out;
1335 if (!svcxdr_encode_gss_init_res(&rqstp->rq_res_stream, &cli_handle,
1336 &ud.out_token, ud.major_status,
1337 ud.minor_status, GSS_SEQ_WIN))
1338 goto out;
1339
1340 ret = SVC_COMPLETE;
1341out:
1342 gss_free_in_token_pages(&ud.in_token);
1343 gssp_free_upcall_data(&ud);
1344 return ret;
1345}
1346
1347/*
1348 * Try to set the sn->use_gss_proxy variable to a new value. We only allow
1349 * it to be changed if it's currently undefined (-1). If it's any other value
1350 * then return -EBUSY unless the type wouldn't have changed anyway.
1351 */
1352static int set_gss_proxy(struct net *net, int type)
1353{
1354 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1355 int ret;
1356
1357 WARN_ON_ONCE(type != 0 && type != 1);
1358 ret = cmpxchg(&sn->use_gss_proxy, -1, type);
1359 if (ret != -1 && ret != type)
1360 return -EBUSY;
1361 return 0;
1362}
1363
1364static bool use_gss_proxy(struct net *net)
1365{
1366 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1367
1368 /* If use_gss_proxy is still undefined, then try to disable it */
1369 if (sn->use_gss_proxy == -1)
1370 set_gss_proxy(net, 0);
1371 return sn->use_gss_proxy;
1372}
1373
1374static noinline_for_stack int
1375svcauth_gss_proc_init(struct svc_rqst *rqstp, struct rpc_gss_wire_cred *gc)
1376{
1377 struct xdr_stream *xdr = &rqstp->rq_arg_stream;
1378 u32 flavor, len;
1379 void *body;
1380
1381 /* Call's verf field: */
1382 if (xdr_stream_decode_opaque_auth(xdr, &flavor, &body, &len) < 0)
1383 return SVC_GARBAGE;
1384 if (flavor != RPC_AUTH_NULL || len != 0) {
1385 rqstp->rq_auth_stat = rpc_autherr_badverf;
1386 return SVC_DENIED;
1387 }
1388
1389 if (gc->gc_proc == RPC_GSS_PROC_INIT && gc->gc_ctx.len != 0) {
1390 rqstp->rq_auth_stat = rpc_autherr_badcred;
1391 return SVC_DENIED;
1392 }
1393
1394 if (!use_gss_proxy(SVC_NET(rqstp)))
1395 return svcauth_gss_legacy_init(rqstp, gc);
1396 return svcauth_gss_proxy_init(rqstp, gc);
1397}
1398
1399#ifdef CONFIG_PROC_FS
1400
1401static ssize_t write_gssp(struct file *file, const char __user *buf,
1402 size_t count, loff_t *ppos)
1403{
1404 struct net *net = pde_data(file_inode(file));
1405 char tbuf[20];
1406 unsigned long i;
1407 int res;
1408
1409 if (*ppos || count > sizeof(tbuf)-1)
1410 return -EINVAL;
1411 if (copy_from_user(tbuf, buf, count))
1412 return -EFAULT;
1413
1414 tbuf[count] = 0;
1415 res = kstrtoul(tbuf, 0, &i);
1416 if (res)
1417 return res;
1418 if (i != 1)
1419 return -EINVAL;
1420 res = set_gssp_clnt(net);
1421 if (res)
1422 return res;
1423 res = set_gss_proxy(net, 1);
1424 if (res)
1425 return res;
1426 return count;
1427}
1428
1429static ssize_t read_gssp(struct file *file, char __user *buf,
1430 size_t count, loff_t *ppos)
1431{
1432 struct net *net = pde_data(file_inode(file));
1433 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1434 unsigned long p = *ppos;
1435 char tbuf[10];
1436 size_t len;
1437
1438 snprintf(tbuf, sizeof(tbuf), "%d\n", sn->use_gss_proxy);
1439 len = strlen(tbuf);
1440 if (p >= len)
1441 return 0;
1442 len -= p;
1443 if (len > count)
1444 len = count;
1445 if (copy_to_user(buf, (void *)(tbuf+p), len))
1446 return -EFAULT;
1447 *ppos += len;
1448 return len;
1449}
1450
1451static const struct proc_ops use_gss_proxy_proc_ops = {
1452 .proc_open = nonseekable_open,
1453 .proc_write = write_gssp,
1454 .proc_read = read_gssp,
1455};
1456
1457static int create_use_gss_proxy_proc_entry(struct net *net)
1458{
1459 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1460 struct proc_dir_entry **p = &sn->use_gssp_proc;
1461
1462 sn->use_gss_proxy = -1;
1463 *p = proc_create_data("use-gss-proxy", S_IFREG | 0600,
1464 sn->proc_net_rpc,
1465 &use_gss_proxy_proc_ops, net);
1466 if (!*p)
1467 return -ENOMEM;
1468 init_gssp_clnt(sn);
1469 return 0;
1470}
1471
1472static void destroy_use_gss_proxy_proc_entry(struct net *net)
1473{
1474 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1475
1476 if (sn->use_gssp_proc) {
1477 remove_proc_entry("use-gss-proxy", sn->proc_net_rpc);
1478 clear_gssp_clnt(sn);
1479 }
1480}
1481
1482static ssize_t read_gss_krb5_enctypes(struct file *file, char __user *buf,
1483 size_t count, loff_t *ppos)
1484{
1485 struct rpcsec_gss_oid oid = {
1486 .len = 9,
1487 .data = "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02",
1488 };
1489 struct gss_api_mech *mech;
1490 ssize_t ret;
1491
1492 mech = gss_mech_get_by_OID(&oid);
1493 if (!mech)
1494 return 0;
1495 if (!mech->gm_upcall_enctypes) {
1496 gss_mech_put(mech);
1497 return 0;
1498 }
1499
1500 ret = simple_read_from_buffer(buf, count, ppos,
1501 mech->gm_upcall_enctypes,
1502 strlen(mech->gm_upcall_enctypes));
1503 gss_mech_put(mech);
1504 return ret;
1505}
1506
1507static const struct proc_ops gss_krb5_enctypes_proc_ops = {
1508 .proc_open = nonseekable_open,
1509 .proc_read = read_gss_krb5_enctypes,
1510};
1511
1512static int create_krb5_enctypes_proc_entry(struct net *net)
1513{
1514 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1515
1516 sn->gss_krb5_enctypes =
1517 proc_create_data("gss_krb5_enctypes", S_IFREG | 0444,
1518 sn->proc_net_rpc, &gss_krb5_enctypes_proc_ops,
1519 net);
1520 return sn->gss_krb5_enctypes ? 0 : -ENOMEM;
1521}
1522
1523static void destroy_krb5_enctypes_proc_entry(struct net *net)
1524{
1525 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1526
1527 if (sn->gss_krb5_enctypes)
1528 remove_proc_entry("gss_krb5_enctypes", sn->proc_net_rpc);
1529}
1530
1531#else /* CONFIG_PROC_FS */
1532
1533static int create_use_gss_proxy_proc_entry(struct net *net)
1534{
1535 return 0;
1536}
1537
1538static void destroy_use_gss_proxy_proc_entry(struct net *net) {}
1539
1540static int create_krb5_enctypes_proc_entry(struct net *net)
1541{
1542 return 0;
1543}
1544
1545static void destroy_krb5_enctypes_proc_entry(struct net *net) {}
1546
1547#endif /* CONFIG_PROC_FS */
1548
1549/*
1550 * The Call's credential body should contain a struct rpc_gss_cred_t.
1551 *
1552 * RFC 2203 Section 5
1553 *
1554 * struct rpc_gss_cred_t {
1555 * union switch (unsigned int version) {
1556 * case RPCSEC_GSS_VERS_1:
1557 * struct {
1558 * rpc_gss_proc_t gss_proc;
1559 * unsigned int seq_num;
1560 * rpc_gss_service_t service;
1561 * opaque handle<>;
1562 * } rpc_gss_cred_vers_1_t;
1563 * }
1564 * };
1565 */
1566static bool
1567svcauth_gss_decode_credbody(struct xdr_stream *xdr,
1568 struct rpc_gss_wire_cred *gc,
1569 __be32 **rpcstart)
1570{
1571 ssize_t handle_len;
1572 u32 body_len;
1573 __be32 *p;
1574
1575 p = xdr_inline_decode(xdr, XDR_UNIT);
1576 if (!p)
1577 return false;
1578 /*
1579 * start of rpc packet is 7 u32's back from here:
1580 * xid direction rpcversion prog vers proc flavour
1581 */
1582 *rpcstart = p - 7;
1583 body_len = be32_to_cpup(p);
1584 if (body_len > RPC_MAX_AUTH_SIZE)
1585 return false;
1586
1587 /* struct rpc_gss_cred_t */
1588 if (xdr_stream_decode_u32(xdr, &gc->gc_v) < 0)
1589 return false;
1590 if (xdr_stream_decode_u32(xdr, &gc->gc_proc) < 0)
1591 return false;
1592 if (xdr_stream_decode_u32(xdr, &gc->gc_seq) < 0)
1593 return false;
1594 if (xdr_stream_decode_u32(xdr, &gc->gc_svc) < 0)
1595 return false;
1596 handle_len = xdr_stream_decode_opaque_inline(xdr,
1597 (void **)&gc->gc_ctx.data,
1598 body_len);
1599 if (handle_len < 0)
1600 return false;
1601 if (body_len != XDR_UNIT * 5 + xdr_align_size(handle_len))
1602 return false;
1603
1604 gc->gc_ctx.len = handle_len;
1605 return true;
1606}
1607
1608/**
1609 * svcauth_gss_accept - Decode and validate incoming RPC_AUTH_GSS credential
1610 * @rqstp: RPC transaction
1611 *
1612 * Return values:
1613 * %SVC_OK: Success
1614 * %SVC_COMPLETE: GSS context lifetime event
1615 * %SVC_DENIED: Credential or verifier is not valid
1616 * %SVC_GARBAGE: Failed to decode credential or verifier
1617 * %SVC_CLOSE: Temporary failure
1618 *
1619 * The rqstp->rq_auth_stat field is also set (see RFCs 2203 and 5531).
1620 */
1621static enum svc_auth_status
1622svcauth_gss_accept(struct svc_rqst *rqstp)
1623{
1624 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
1625 __be32 *rpcstart;
1626 struct rpc_gss_wire_cred *gc;
1627 struct rsc *rsci = NULL;
1628 int ret;
1629 struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id);
1630
1631 rqstp->rq_auth_stat = rpc_autherr_badcred;
1632 if (!svcdata)
1633 svcdata = kmalloc(sizeof(*svcdata), GFP_KERNEL);
1634 if (!svcdata)
1635 goto auth_err;
1636 rqstp->rq_auth_data = svcdata;
1637 svcdata->gsd_databody_offset = 0;
1638 svcdata->rsci = NULL;
1639 gc = &svcdata->clcred;
1640
1641 if (!svcauth_gss_decode_credbody(&rqstp->rq_arg_stream, gc, &rpcstart))
1642 goto auth_err;
1643 if (gc->gc_v != RPC_GSS_VERSION)
1644 goto auth_err;
1645
1646 switch (gc->gc_proc) {
1647 case RPC_GSS_PROC_INIT:
1648 case RPC_GSS_PROC_CONTINUE_INIT:
1649 if (rqstp->rq_proc != 0)
1650 goto auth_err;
1651 return svcauth_gss_proc_init(rqstp, gc);
1652 case RPC_GSS_PROC_DESTROY:
1653 if (rqstp->rq_proc != 0)
1654 goto auth_err;
1655 fallthrough;
1656 case RPC_GSS_PROC_DATA:
1657 rqstp->rq_auth_stat = rpcsec_gsserr_credproblem;
1658 rsci = gss_svc_searchbyctx(sn->rsc_cache, &gc->gc_ctx);
1659 if (!rsci)
1660 goto auth_err;
1661 switch (svcauth_gss_verify_header(rqstp, rsci, rpcstart, gc)) {
1662 case SVC_OK:
1663 break;
1664 case SVC_DENIED:
1665 goto auth_err;
1666 case SVC_DROP:
1667 goto drop;
1668 }
1669 break;
1670 default:
1671 if (rqstp->rq_proc != 0)
1672 goto auth_err;
1673 rqstp->rq_auth_stat = rpc_autherr_rejectedcred;
1674 goto auth_err;
1675 }
1676
1677 /* now act upon the command: */
1678 switch (gc->gc_proc) {
1679 case RPC_GSS_PROC_DESTROY:
1680 if (!svcauth_gss_encode_verf(rqstp, rsci->mechctx, gc->gc_seq))
1681 goto auth_err;
1682 if (!svcxdr_set_accept_stat(rqstp))
1683 goto auth_err;
1684 /* Delete the entry from the cache_list and call cache_put */
1685 sunrpc_cache_unhash(sn->rsc_cache, &rsci->h);
1686 goto complete;
1687 case RPC_GSS_PROC_DATA:
1688 rqstp->rq_auth_stat = rpcsec_gsserr_ctxproblem;
1689 if (!svcauth_gss_encode_verf(rqstp, rsci->mechctx, gc->gc_seq))
1690 goto auth_err;
1691 if (!svcxdr_set_accept_stat(rqstp))
1692 goto auth_err;
1693 svcdata->gsd_databody_offset = xdr_stream_pos(&rqstp->rq_res_stream);
1694 rqstp->rq_cred = rsci->cred;
1695 get_group_info(rsci->cred.cr_group_info);
1696 rqstp->rq_auth_stat = rpc_autherr_badcred;
1697 switch (gc->gc_svc) {
1698 case RPC_GSS_SVC_NONE:
1699 break;
1700 case RPC_GSS_SVC_INTEGRITY:
1701 /* placeholders for body length and seq. number: */
1702 xdr_reserve_space(&rqstp->rq_res_stream, XDR_UNIT * 2);
1703 if (svcauth_gss_unwrap_integ(rqstp, gc->gc_seq,
1704 rsci->mechctx))
1705 goto garbage_args;
1706 svcxdr_set_auth_slack(rqstp, RPC_MAX_AUTH_SIZE);
1707 break;
1708 case RPC_GSS_SVC_PRIVACY:
1709 /* placeholders for body length and seq. number: */
1710 xdr_reserve_space(&rqstp->rq_res_stream, XDR_UNIT * 2);
1711 if (svcauth_gss_unwrap_priv(rqstp, gc->gc_seq,
1712 rsci->mechctx))
1713 goto garbage_args;
1714 svcxdr_set_auth_slack(rqstp, RPC_MAX_AUTH_SIZE * 2);
1715 break;
1716 default:
1717 goto auth_err;
1718 }
1719 svcdata->rsci = rsci;
1720 cache_get(&rsci->h);
1721 rqstp->rq_cred.cr_flavor = gss_svc_to_pseudoflavor(
1722 rsci->mechctx->mech_type,
1723 GSS_C_QOP_DEFAULT,
1724 gc->gc_svc);
1725 ret = SVC_OK;
1726 trace_rpcgss_svc_authenticate(rqstp, gc);
1727 goto out;
1728 }
1729garbage_args:
1730 ret = SVC_GARBAGE;
1731 goto out;
1732auth_err:
1733 xdr_truncate_encode(&rqstp->rq_res_stream, XDR_UNIT * 2);
1734 ret = SVC_DENIED;
1735 goto out;
1736complete:
1737 ret = SVC_COMPLETE;
1738 goto out;
1739drop:
1740 ret = SVC_CLOSE;
1741out:
1742 if (rsci)
1743 cache_put(&rsci->h, sn->rsc_cache);
1744 return ret;
1745}
1746
1747static u32
1748svcauth_gss_prepare_to_wrap(struct svc_rqst *rqstp, struct gss_svc_data *gsd)
1749{
1750 u32 offset;
1751
1752 /* Release can be called twice, but we only wrap once. */
1753 offset = gsd->gsd_databody_offset;
1754 gsd->gsd_databody_offset = 0;
1755
1756 /* AUTH_ERROR replies are not wrapped. */
1757 if (rqstp->rq_auth_stat != rpc_auth_ok)
1758 return 0;
1759
1760 /* Also don't wrap if the accept_stat is nonzero: */
1761 if (*rqstp->rq_accept_statp != rpc_success)
1762 return 0;
1763
1764 return offset;
1765}
1766
1767/*
1768 * RFC 2203, Section 5.3.2.2
1769 *
1770 * struct rpc_gss_integ_data {
1771 * opaque databody_integ<>;
1772 * opaque checksum<>;
1773 * };
1774 *
1775 * struct rpc_gss_data_t {
1776 * unsigned int seq_num;
1777 * proc_req_arg_t arg;
1778 * };
1779 *
1780 * The RPC Reply message has already been XDR-encoded. rq_res_stream
1781 * is now positioned so that the checksum can be written just past
1782 * the RPC Reply message.
1783 */
1784static int svcauth_gss_wrap_integ(struct svc_rqst *rqstp)
1785{
1786 struct gss_svc_data *gsd = rqstp->rq_auth_data;
1787 struct xdr_stream *xdr = &rqstp->rq_res_stream;
1788 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1789 struct xdr_buf *buf = xdr->buf;
1790 struct xdr_buf databody_integ;
1791 struct xdr_netobj checksum;
1792 u32 offset, maj_stat;
1793
1794 offset = svcauth_gss_prepare_to_wrap(rqstp, gsd);
1795 if (!offset)
1796 goto out;
1797
1798 if (xdr_buf_subsegment(buf, &databody_integ, offset + XDR_UNIT,
1799 buf->len - offset - XDR_UNIT))
1800 goto wrap_failed;
1801 /* Buffer space for these has already been reserved in
1802 * svcauth_gss_accept(). */
1803 if (xdr_encode_word(buf, offset, databody_integ.len))
1804 goto wrap_failed;
1805 if (xdr_encode_word(buf, offset + XDR_UNIT, gc->gc_seq))
1806 goto wrap_failed;
1807
1808 checksum.data = gsd->gsd_scratch;
1809 maj_stat = gss_get_mic(gsd->rsci->mechctx, &databody_integ, &checksum);
1810 if (maj_stat != GSS_S_COMPLETE)
1811 goto bad_mic;
1812
1813 if (xdr_stream_encode_opaque(xdr, checksum.data, checksum.len) < 0)
1814 goto wrap_failed;
1815 xdr_commit_encode(xdr);
1816
1817out:
1818 return 0;
1819
1820bad_mic:
1821 trace_rpcgss_svc_get_mic(rqstp, maj_stat);
1822 return -EINVAL;
1823wrap_failed:
1824 trace_rpcgss_svc_wrap_failed(rqstp);
1825 return -EINVAL;
1826}
1827
1828/*
1829 * RFC 2203, Section 5.3.2.3
1830 *
1831 * struct rpc_gss_priv_data {
1832 * opaque databody_priv<>
1833 * };
1834 *
1835 * struct rpc_gss_data_t {
1836 * unsigned int seq_num;
1837 * proc_req_arg_t arg;
1838 * };
1839 *
1840 * gss_wrap() expands the size of the RPC message payload in the
1841 * response buffer. The main purpose of svcauth_gss_wrap_priv()
1842 * is to ensure there is adequate space in the response buffer to
1843 * avoid overflow during the wrap.
1844 */
1845static int svcauth_gss_wrap_priv(struct svc_rqst *rqstp)
1846{
1847 struct gss_svc_data *gsd = rqstp->rq_auth_data;
1848 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1849 struct xdr_buf *buf = &rqstp->rq_res;
1850 struct kvec *head = buf->head;
1851 struct kvec *tail = buf->tail;
1852 u32 offset, pad, maj_stat;
1853 __be32 *p;
1854
1855 offset = svcauth_gss_prepare_to_wrap(rqstp, gsd);
1856 if (!offset)
1857 return 0;
1858
1859 /*
1860 * Buffer space for this field has already been reserved
1861 * in svcauth_gss_accept(). Note that the GSS sequence
1862 * number is encrypted along with the RPC reply payload.
1863 */
1864 if (xdr_encode_word(buf, offset + XDR_UNIT, gc->gc_seq))
1865 goto wrap_failed;
1866
1867 /*
1868 * If there is currently tail data, make sure there is
1869 * room for the head, tail, and 2 * RPC_MAX_AUTH_SIZE in
1870 * the page, and move the current tail data such that
1871 * there is RPC_MAX_AUTH_SIZE slack space available in
1872 * both the head and tail.
1873 */
1874 if (tail->iov_base) {
1875 if (tail->iov_base >= head->iov_base + PAGE_SIZE)
1876 goto wrap_failed;
1877 if (tail->iov_base < head->iov_base)
1878 goto wrap_failed;
1879 if (tail->iov_len + head->iov_len
1880 + 2 * RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1881 goto wrap_failed;
1882 memmove(tail->iov_base + RPC_MAX_AUTH_SIZE, tail->iov_base,
1883 tail->iov_len);
1884 tail->iov_base += RPC_MAX_AUTH_SIZE;
1885 }
1886 /*
1887 * If there is no current tail data, make sure there is
1888 * room for the head data, and 2 * RPC_MAX_AUTH_SIZE in the
1889 * allotted page, and set up tail information such that there
1890 * is RPC_MAX_AUTH_SIZE slack space available in both the
1891 * head and tail.
1892 */
1893 if (!tail->iov_base) {
1894 if (head->iov_len + 2 * RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1895 goto wrap_failed;
1896 tail->iov_base = head->iov_base
1897 + head->iov_len + RPC_MAX_AUTH_SIZE;
1898 tail->iov_len = 0;
1899 }
1900
1901 maj_stat = gss_wrap(gsd->rsci->mechctx, offset + XDR_UNIT, buf,
1902 buf->pages);
1903 if (maj_stat != GSS_S_COMPLETE)
1904 goto bad_wrap;
1905
1906 /* Wrapping can change the size of databody_priv. */
1907 if (xdr_encode_word(buf, offset, buf->len - offset - XDR_UNIT))
1908 goto wrap_failed;
1909 pad = xdr_pad_size(buf->len - offset - XDR_UNIT);
1910 p = (__be32 *)(tail->iov_base + tail->iov_len);
1911 memset(p, 0, pad);
1912 tail->iov_len += pad;
1913 buf->len += pad;
1914
1915 return 0;
1916wrap_failed:
1917 trace_rpcgss_svc_wrap_failed(rqstp);
1918 return -EINVAL;
1919bad_wrap:
1920 trace_rpcgss_svc_wrap(rqstp, maj_stat);
1921 return -ENOMEM;
1922}
1923
1924/**
1925 * svcauth_gss_release - Wrap payload and release resources
1926 * @rqstp: RPC transaction context
1927 *
1928 * Return values:
1929 * %0: the Reply is ready to be sent
1930 * %-ENOMEM: failed to allocate memory
1931 * %-EINVAL: encoding error
1932 */
1933static int
1934svcauth_gss_release(struct svc_rqst *rqstp)
1935{
1936 struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id);
1937 struct gss_svc_data *gsd = rqstp->rq_auth_data;
1938 struct rpc_gss_wire_cred *gc;
1939 int stat;
1940
1941 if (!gsd)
1942 goto out;
1943 gc = &gsd->clcred;
1944 if (gc->gc_proc != RPC_GSS_PROC_DATA)
1945 goto out;
1946
1947 switch (gc->gc_svc) {
1948 case RPC_GSS_SVC_NONE:
1949 break;
1950 case RPC_GSS_SVC_INTEGRITY:
1951 stat = svcauth_gss_wrap_integ(rqstp);
1952 if (stat)
1953 goto out_err;
1954 break;
1955 case RPC_GSS_SVC_PRIVACY:
1956 stat = svcauth_gss_wrap_priv(rqstp);
1957 if (stat)
1958 goto out_err;
1959 break;
1960 /*
1961 * For any other gc_svc value, svcauth_gss_accept() already set
1962 * the auth_error appropriately; just fall through:
1963 */
1964 }
1965
1966out:
1967 stat = 0;
1968out_err:
1969 if (rqstp->rq_client)
1970 auth_domain_put(rqstp->rq_client);
1971 rqstp->rq_client = NULL;
1972 if (rqstp->rq_gssclient)
1973 auth_domain_put(rqstp->rq_gssclient);
1974 rqstp->rq_gssclient = NULL;
1975 if (rqstp->rq_cred.cr_group_info)
1976 put_group_info(rqstp->rq_cred.cr_group_info);
1977 rqstp->rq_cred.cr_group_info = NULL;
1978 if (gsd && gsd->rsci) {
1979 cache_put(&gsd->rsci->h, sn->rsc_cache);
1980 gsd->rsci = NULL;
1981 }
1982 return stat;
1983}
1984
1985static void
1986svcauth_gss_domain_release_rcu(struct rcu_head *head)
1987{
1988 struct auth_domain *dom = container_of(head, struct auth_domain, rcu_head);
1989 struct gss_domain *gd = container_of(dom, struct gss_domain, h);
1990
1991 kfree(dom->name);
1992 kfree(gd);
1993}
1994
1995static void
1996svcauth_gss_domain_release(struct auth_domain *dom)
1997{
1998 call_rcu(&dom->rcu_head, svcauth_gss_domain_release_rcu);
1999}
2000
2001static rpc_authflavor_t svcauth_gss_pseudoflavor(struct svc_rqst *rqstp)
2002{
2003 return svcauth_gss_flavor(rqstp->rq_gssclient);
2004}
2005
2006static struct auth_ops svcauthops_gss = {
2007 .name = "rpcsec_gss",
2008 .owner = THIS_MODULE,
2009 .flavour = RPC_AUTH_GSS,
2010 .accept = svcauth_gss_accept,
2011 .release = svcauth_gss_release,
2012 .domain_release = svcauth_gss_domain_release,
2013 .set_client = svcauth_gss_set_client,
2014 .pseudoflavor = svcauth_gss_pseudoflavor,
2015};
2016
2017static int rsi_cache_create_net(struct net *net)
2018{
2019 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
2020 struct cache_detail *cd;
2021 int err;
2022
2023 cd = cache_create_net(&rsi_cache_template, net);
2024 if (IS_ERR(cd))
2025 return PTR_ERR(cd);
2026 err = cache_register_net(cd, net);
2027 if (err) {
2028 cache_destroy_net(cd, net);
2029 return err;
2030 }
2031 sn->rsi_cache = cd;
2032 return 0;
2033}
2034
2035static void rsi_cache_destroy_net(struct net *net)
2036{
2037 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
2038 struct cache_detail *cd = sn->rsi_cache;
2039
2040 sn->rsi_cache = NULL;
2041 cache_purge(cd);
2042 cache_unregister_net(cd, net);
2043 cache_destroy_net(cd, net);
2044}
2045
2046static int rsc_cache_create_net(struct net *net)
2047{
2048 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
2049 struct cache_detail *cd;
2050 int err;
2051
2052 cd = cache_create_net(&rsc_cache_template, net);
2053 if (IS_ERR(cd))
2054 return PTR_ERR(cd);
2055 err = cache_register_net(cd, net);
2056 if (err) {
2057 cache_destroy_net(cd, net);
2058 return err;
2059 }
2060 sn->rsc_cache = cd;
2061 return 0;
2062}
2063
2064static void rsc_cache_destroy_net(struct net *net)
2065{
2066 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
2067 struct cache_detail *cd = sn->rsc_cache;
2068
2069 sn->rsc_cache = NULL;
2070 cache_purge(cd);
2071 cache_unregister_net(cd, net);
2072 cache_destroy_net(cd, net);
2073}
2074
2075int
2076gss_svc_init_net(struct net *net)
2077{
2078 int rv;
2079
2080 rv = rsc_cache_create_net(net);
2081 if (rv)
2082 return rv;
2083 rv = rsi_cache_create_net(net);
2084 if (rv)
2085 goto out1;
2086 rv = create_use_gss_proxy_proc_entry(net);
2087 if (rv)
2088 goto out2;
2089
2090 rv = create_krb5_enctypes_proc_entry(net);
2091 if (rv)
2092 goto out3;
2093
2094 return 0;
2095
2096out3:
2097 destroy_use_gss_proxy_proc_entry(net);
2098out2:
2099 rsi_cache_destroy_net(net);
2100out1:
2101 rsc_cache_destroy_net(net);
2102 return rv;
2103}
2104
2105void
2106gss_svc_shutdown_net(struct net *net)
2107{
2108 destroy_krb5_enctypes_proc_entry(net);
2109 destroy_use_gss_proxy_proc_entry(net);
2110 rsi_cache_destroy_net(net);
2111 rsc_cache_destroy_net(net);
2112}
2113
2114int
2115gss_svc_init(void)
2116{
2117 return svc_auth_register(RPC_AUTH_GSS, &svcauthops_gss);
2118}
2119
2120void
2121gss_svc_shutdown(void)
2122{
2123 svc_auth_unregister(RPC_AUTH_GSS);
2124}
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#include <linux/user_namespace.h>
45
46#include <linux/sunrpc/auth_gss.h>
47#include <linux/sunrpc/gss_err.h>
48#include <linux/sunrpc/svcauth.h>
49#include <linux/sunrpc/svcauth_gss.h>
50#include <linux/sunrpc/cache.h>
51#include "gss_rpc_upcall.h"
52
53
54#ifdef RPC_DEBUG
55# define RPCDBG_FACILITY RPCDBG_AUTH
56#endif
57
58/* The rpcsec_init cache is used for mapping RPCSEC_GSS_{,CONT_}INIT requests
59 * into replies.
60 *
61 * Key is context handle (\x if empty) and gss_token.
62 * Content is major_status minor_status (integers) context_handle, reply_token.
63 *
64 */
65
66static int netobj_equal(struct xdr_netobj *a, struct xdr_netobj *b)
67{
68 return a->len == b->len && 0 == memcmp(a->data, b->data, a->len);
69}
70
71#define RSI_HASHBITS 6
72#define RSI_HASHMAX (1<<RSI_HASHBITS)
73
74struct rsi {
75 struct cache_head h;
76 struct xdr_netobj in_handle, in_token;
77 struct xdr_netobj out_handle, out_token;
78 int major_status, minor_status;
79};
80
81static struct rsi *rsi_update(struct cache_detail *cd, struct rsi *new, struct rsi *old);
82static struct rsi *rsi_lookup(struct cache_detail *cd, struct rsi *item);
83
84static void rsi_free(struct rsi *rsii)
85{
86 kfree(rsii->in_handle.data);
87 kfree(rsii->in_token.data);
88 kfree(rsii->out_handle.data);
89 kfree(rsii->out_token.data);
90}
91
92static void rsi_put(struct kref *ref)
93{
94 struct rsi *rsii = container_of(ref, struct rsi, h.ref);
95 rsi_free(rsii);
96 kfree(rsii);
97}
98
99static inline int rsi_hash(struct rsi *item)
100{
101 return hash_mem(item->in_handle.data, item->in_handle.len, RSI_HASHBITS)
102 ^ hash_mem(item->in_token.data, item->in_token.len, RSI_HASHBITS);
103}
104
105static int rsi_match(struct cache_head *a, struct cache_head *b)
106{
107 struct rsi *item = container_of(a, struct rsi, h);
108 struct rsi *tmp = container_of(b, struct rsi, h);
109 return netobj_equal(&item->in_handle, &tmp->in_handle) &&
110 netobj_equal(&item->in_token, &tmp->in_token);
111}
112
113static int dup_to_netobj(struct xdr_netobj *dst, char *src, int len)
114{
115 dst->len = len;
116 dst->data = (len ? kmemdup(src, len, GFP_KERNEL) : NULL);
117 if (len && !dst->data)
118 return -ENOMEM;
119 return 0;
120}
121
122static inline int dup_netobj(struct xdr_netobj *dst, struct xdr_netobj *src)
123{
124 return dup_to_netobj(dst, src->data, src->len);
125}
126
127static void rsi_init(struct cache_head *cnew, struct cache_head *citem)
128{
129 struct rsi *new = container_of(cnew, struct rsi, h);
130 struct rsi *item = container_of(citem, struct rsi, h);
131
132 new->out_handle.data = NULL;
133 new->out_handle.len = 0;
134 new->out_token.data = NULL;
135 new->out_token.len = 0;
136 new->in_handle.len = item->in_handle.len;
137 item->in_handle.len = 0;
138 new->in_token.len = item->in_token.len;
139 item->in_token.len = 0;
140 new->in_handle.data = item->in_handle.data;
141 item->in_handle.data = NULL;
142 new->in_token.data = item->in_token.data;
143 item->in_token.data = NULL;
144}
145
146static void update_rsi(struct cache_head *cnew, struct cache_head *citem)
147{
148 struct rsi *new = container_of(cnew, struct rsi, h);
149 struct rsi *item = container_of(citem, struct rsi, h);
150
151 BUG_ON(new->out_handle.data || new->out_token.data);
152 new->out_handle.len = item->out_handle.len;
153 item->out_handle.len = 0;
154 new->out_token.len = item->out_token.len;
155 item->out_token.len = 0;
156 new->out_handle.data = item->out_handle.data;
157 item->out_handle.data = NULL;
158 new->out_token.data = item->out_token.data;
159 item->out_token.data = NULL;
160
161 new->major_status = item->major_status;
162 new->minor_status = item->minor_status;
163}
164
165static struct cache_head *rsi_alloc(void)
166{
167 struct rsi *rsii = kmalloc(sizeof(*rsii), GFP_KERNEL);
168 if (rsii)
169 return &rsii->h;
170 else
171 return NULL;
172}
173
174static void rsi_request(struct cache_detail *cd,
175 struct cache_head *h,
176 char **bpp, int *blen)
177{
178 struct rsi *rsii = container_of(h, struct rsi, h);
179
180 qword_addhex(bpp, blen, rsii->in_handle.data, rsii->in_handle.len);
181 qword_addhex(bpp, blen, rsii->in_token.data, rsii->in_token.len);
182 (*bpp)[-1] = '\n';
183}
184
185static int rsi_parse(struct cache_detail *cd,
186 char *mesg, int mlen)
187{
188 /* context token expiry major minor context token */
189 char *buf = mesg;
190 char *ep;
191 int len;
192 struct rsi rsii, *rsip = NULL;
193 time_t expiry;
194 int status = -EINVAL;
195
196 memset(&rsii, 0, sizeof(rsii));
197 /* handle */
198 len = qword_get(&mesg, buf, mlen);
199 if (len < 0)
200 goto out;
201 status = -ENOMEM;
202 if (dup_to_netobj(&rsii.in_handle, buf, len))
203 goto out;
204
205 /* token */
206 len = qword_get(&mesg, buf, mlen);
207 status = -EINVAL;
208 if (len < 0)
209 goto out;
210 status = -ENOMEM;
211 if (dup_to_netobj(&rsii.in_token, buf, len))
212 goto out;
213
214 rsip = rsi_lookup(cd, &rsii);
215 if (!rsip)
216 goto out;
217
218 rsii.h.flags = 0;
219 /* expiry */
220 expiry = get_expiry(&mesg);
221 status = -EINVAL;
222 if (expiry == 0)
223 goto out;
224
225 /* major/minor */
226 len = qword_get(&mesg, buf, mlen);
227 if (len <= 0)
228 goto out;
229 rsii.major_status = simple_strtoul(buf, &ep, 10);
230 if (*ep)
231 goto out;
232 len = qword_get(&mesg, buf, mlen);
233 if (len <= 0)
234 goto out;
235 rsii.minor_status = simple_strtoul(buf, &ep, 10);
236 if (*ep)
237 goto out;
238
239 /* out_handle */
240 len = qword_get(&mesg, buf, mlen);
241 if (len < 0)
242 goto out;
243 status = -ENOMEM;
244 if (dup_to_netobj(&rsii.out_handle, buf, len))
245 goto out;
246
247 /* out_token */
248 len = qword_get(&mesg, buf, mlen);
249 status = -EINVAL;
250 if (len < 0)
251 goto out;
252 status = -ENOMEM;
253 if (dup_to_netobj(&rsii.out_token, buf, len))
254 goto out;
255 rsii.h.expiry_time = expiry;
256 rsip = rsi_update(cd, &rsii, rsip);
257 status = 0;
258out:
259 rsi_free(&rsii);
260 if (rsip)
261 cache_put(&rsip->h, cd);
262 else
263 status = -ENOMEM;
264 return status;
265}
266
267static struct cache_detail rsi_cache_template = {
268 .owner = THIS_MODULE,
269 .hash_size = RSI_HASHMAX,
270 .name = "auth.rpcsec.init",
271 .cache_put = rsi_put,
272 .cache_request = rsi_request,
273 .cache_parse = rsi_parse,
274 .match = rsi_match,
275 .init = rsi_init,
276 .update = update_rsi,
277 .alloc = rsi_alloc,
278};
279
280static struct rsi *rsi_lookup(struct cache_detail *cd, struct rsi *item)
281{
282 struct cache_head *ch;
283 int hash = rsi_hash(item);
284
285 ch = sunrpc_cache_lookup(cd, &item->h, hash);
286 if (ch)
287 return container_of(ch, struct rsi, h);
288 else
289 return NULL;
290}
291
292static struct rsi *rsi_update(struct cache_detail *cd, struct rsi *new, struct rsi *old)
293{
294 struct cache_head *ch;
295 int hash = rsi_hash(new);
296
297 ch = sunrpc_cache_update(cd, &new->h,
298 &old->h, hash);
299 if (ch)
300 return container_of(ch, struct rsi, h);
301 else
302 return NULL;
303}
304
305
306/*
307 * The rpcsec_context cache is used to store a context that is
308 * used in data exchange.
309 * The key is a context handle. The content is:
310 * uid, gidlist, mechanism, service-set, mech-specific-data
311 */
312
313#define RSC_HASHBITS 10
314#define RSC_HASHMAX (1<<RSC_HASHBITS)
315
316#define GSS_SEQ_WIN 128
317
318struct gss_svc_seq_data {
319 /* highest seq number seen so far: */
320 int sd_max;
321 /* for i such that sd_max-GSS_SEQ_WIN < i <= sd_max, the i-th bit of
322 * sd_win is nonzero iff sequence number i has been seen already: */
323 unsigned long sd_win[GSS_SEQ_WIN/BITS_PER_LONG];
324 spinlock_t sd_lock;
325};
326
327struct rsc {
328 struct cache_head h;
329 struct xdr_netobj handle;
330 struct svc_cred cred;
331 struct gss_svc_seq_data seqdata;
332 struct gss_ctx *mechctx;
333};
334
335static struct rsc *rsc_update(struct cache_detail *cd, struct rsc *new, struct rsc *old);
336static struct rsc *rsc_lookup(struct cache_detail *cd, struct rsc *item);
337
338static void rsc_free(struct rsc *rsci)
339{
340 kfree(rsci->handle.data);
341 if (rsci->mechctx)
342 gss_delete_sec_context(&rsci->mechctx);
343 free_svc_cred(&rsci->cred);
344}
345
346static void rsc_put(struct kref *ref)
347{
348 struct rsc *rsci = container_of(ref, struct rsc, h.ref);
349
350 rsc_free(rsci);
351 kfree(rsci);
352}
353
354static inline int
355rsc_hash(struct rsc *rsci)
356{
357 return hash_mem(rsci->handle.data, rsci->handle.len, RSC_HASHBITS);
358}
359
360static int
361rsc_match(struct cache_head *a, struct cache_head *b)
362{
363 struct rsc *new = container_of(a, struct rsc, h);
364 struct rsc *tmp = container_of(b, struct rsc, h);
365
366 return netobj_equal(&new->handle, &tmp->handle);
367}
368
369static void
370rsc_init(struct cache_head *cnew, struct cache_head *ctmp)
371{
372 struct rsc *new = container_of(cnew, struct rsc, h);
373 struct rsc *tmp = container_of(ctmp, struct rsc, h);
374
375 new->handle.len = tmp->handle.len;
376 tmp->handle.len = 0;
377 new->handle.data = tmp->handle.data;
378 tmp->handle.data = NULL;
379 new->mechctx = NULL;
380 init_svc_cred(&new->cred);
381}
382
383static void
384update_rsc(struct cache_head *cnew, struct cache_head *ctmp)
385{
386 struct rsc *new = container_of(cnew, struct rsc, h);
387 struct rsc *tmp = container_of(ctmp, struct rsc, h);
388
389 new->mechctx = tmp->mechctx;
390 tmp->mechctx = NULL;
391 memset(&new->seqdata, 0, sizeof(new->seqdata));
392 spin_lock_init(&new->seqdata.sd_lock);
393 new->cred = tmp->cred;
394 init_svc_cred(&tmp->cred);
395}
396
397static struct cache_head *
398rsc_alloc(void)
399{
400 struct rsc *rsci = kmalloc(sizeof(*rsci), GFP_KERNEL);
401 if (rsci)
402 return &rsci->h;
403 else
404 return NULL;
405}
406
407static int rsc_parse(struct cache_detail *cd,
408 char *mesg, int mlen)
409{
410 /* contexthandle expiry [ uid gid N <n gids> mechname ...mechdata... ] */
411 char *buf = mesg;
412 int id;
413 int len, rv;
414 struct rsc rsci, *rscp = NULL;
415 time_t expiry;
416 int status = -EINVAL;
417 struct gss_api_mech *gm = NULL;
418
419 memset(&rsci, 0, sizeof(rsci));
420 /* context handle */
421 len = qword_get(&mesg, buf, mlen);
422 if (len < 0) goto out;
423 status = -ENOMEM;
424 if (dup_to_netobj(&rsci.handle, buf, len))
425 goto out;
426
427 rsci.h.flags = 0;
428 /* expiry */
429 expiry = get_expiry(&mesg);
430 status = -EINVAL;
431 if (expiry == 0)
432 goto out;
433
434 rscp = rsc_lookup(cd, &rsci);
435 if (!rscp)
436 goto out;
437
438 /* uid, or NEGATIVE */
439 rv = get_int(&mesg, &id);
440 if (rv == -EINVAL)
441 goto out;
442 if (rv == -ENOENT)
443 set_bit(CACHE_NEGATIVE, &rsci.h.flags);
444 else {
445 int N, i;
446
447 /*
448 * NOTE: we skip uid_valid()/gid_valid() checks here:
449 * instead, * -1 id's are later mapped to the
450 * (export-specific) anonymous id by nfsd_setuser.
451 *
452 * (But supplementary gid's get no such special
453 * treatment so are checked for validity here.)
454 */
455 /* uid */
456 rsci.cred.cr_uid = make_kuid(&init_user_ns, id);
457
458 /* gid */
459 if (get_int(&mesg, &id))
460 goto out;
461 rsci.cred.cr_gid = make_kgid(&init_user_ns, id);
462
463 /* number of additional gid's */
464 if (get_int(&mesg, &N))
465 goto out;
466 status = -ENOMEM;
467 rsci.cred.cr_group_info = groups_alloc(N);
468 if (rsci.cred.cr_group_info == NULL)
469 goto out;
470
471 /* gid's */
472 status = -EINVAL;
473 for (i=0; i<N; i++) {
474 kgid_t kgid;
475 if (get_int(&mesg, &id))
476 goto out;
477 kgid = make_kgid(&init_user_ns, id);
478 if (!gid_valid(kgid))
479 goto out;
480 GROUP_AT(rsci.cred.cr_group_info, i) = kgid;
481 }
482
483 /* mech name */
484 len = qword_get(&mesg, buf, mlen);
485 if (len < 0)
486 goto out;
487 gm = rsci.cred.cr_gss_mech = gss_mech_get_by_name(buf);
488 status = -EOPNOTSUPP;
489 if (!gm)
490 goto out;
491
492 status = -EINVAL;
493 /* mech-specific data: */
494 len = qword_get(&mesg, buf, mlen);
495 if (len < 0)
496 goto out;
497 status = gss_import_sec_context(buf, len, gm, &rsci.mechctx,
498 NULL, GFP_KERNEL);
499 if (status)
500 goto out;
501
502 /* get client name */
503 len = qword_get(&mesg, buf, mlen);
504 if (len > 0) {
505 rsci.cred.cr_principal = kstrdup(buf, GFP_KERNEL);
506 if (!rsci.cred.cr_principal) {
507 status = -ENOMEM;
508 goto out;
509 }
510 }
511
512 }
513 rsci.h.expiry_time = expiry;
514 rscp = rsc_update(cd, &rsci, rscp);
515 status = 0;
516out:
517 rsc_free(&rsci);
518 if (rscp)
519 cache_put(&rscp->h, cd);
520 else
521 status = -ENOMEM;
522 return status;
523}
524
525static struct cache_detail rsc_cache_template = {
526 .owner = THIS_MODULE,
527 .hash_size = RSC_HASHMAX,
528 .name = "auth.rpcsec.context",
529 .cache_put = rsc_put,
530 .cache_parse = rsc_parse,
531 .match = rsc_match,
532 .init = rsc_init,
533 .update = update_rsc,
534 .alloc = rsc_alloc,
535};
536
537static struct rsc *rsc_lookup(struct cache_detail *cd, struct rsc *item)
538{
539 struct cache_head *ch;
540 int hash = rsc_hash(item);
541
542 ch = sunrpc_cache_lookup(cd, &item->h, hash);
543 if (ch)
544 return container_of(ch, struct rsc, h);
545 else
546 return NULL;
547}
548
549static struct rsc *rsc_update(struct cache_detail *cd, struct rsc *new, struct rsc *old)
550{
551 struct cache_head *ch;
552 int hash = rsc_hash(new);
553
554 ch = sunrpc_cache_update(cd, &new->h,
555 &old->h, hash);
556 if (ch)
557 return container_of(ch, struct rsc, h);
558 else
559 return NULL;
560}
561
562
563static struct rsc *
564gss_svc_searchbyctx(struct cache_detail *cd, struct xdr_netobj *handle)
565{
566 struct rsc rsci;
567 struct rsc *found;
568
569 memset(&rsci, 0, sizeof(rsci));
570 if (dup_to_netobj(&rsci.handle, handle->data, handle->len))
571 return NULL;
572 found = rsc_lookup(cd, &rsci);
573 rsc_free(&rsci);
574 if (!found)
575 return NULL;
576 if (cache_check(cd, &found->h, NULL))
577 return NULL;
578 return found;
579}
580
581/* Implements sequence number algorithm as specified in RFC 2203. */
582static int
583gss_check_seq_num(struct rsc *rsci, int seq_num)
584{
585 struct gss_svc_seq_data *sd = &rsci->seqdata;
586
587 spin_lock(&sd->sd_lock);
588 if (seq_num > sd->sd_max) {
589 if (seq_num >= sd->sd_max + GSS_SEQ_WIN) {
590 memset(sd->sd_win,0,sizeof(sd->sd_win));
591 sd->sd_max = seq_num;
592 } else while (sd->sd_max < seq_num) {
593 sd->sd_max++;
594 __clear_bit(sd->sd_max % GSS_SEQ_WIN, sd->sd_win);
595 }
596 __set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win);
597 goto ok;
598 } else if (seq_num <= sd->sd_max - GSS_SEQ_WIN) {
599 goto drop;
600 }
601 /* sd_max - GSS_SEQ_WIN < seq_num <= sd_max */
602 if (__test_and_set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win))
603 goto drop;
604ok:
605 spin_unlock(&sd->sd_lock);
606 return 1;
607drop:
608 spin_unlock(&sd->sd_lock);
609 return 0;
610}
611
612static inline u32 round_up_to_quad(u32 i)
613{
614 return (i + 3 ) & ~3;
615}
616
617static inline int
618svc_safe_getnetobj(struct kvec *argv, struct xdr_netobj *o)
619{
620 int l;
621
622 if (argv->iov_len < 4)
623 return -1;
624 o->len = svc_getnl(argv);
625 l = round_up_to_quad(o->len);
626 if (argv->iov_len < l)
627 return -1;
628 o->data = argv->iov_base;
629 argv->iov_base += l;
630 argv->iov_len -= l;
631 return 0;
632}
633
634static inline int
635svc_safe_putnetobj(struct kvec *resv, struct xdr_netobj *o)
636{
637 u8 *p;
638
639 if (resv->iov_len + 4 > PAGE_SIZE)
640 return -1;
641 svc_putnl(resv, o->len);
642 p = resv->iov_base + resv->iov_len;
643 resv->iov_len += round_up_to_quad(o->len);
644 if (resv->iov_len > PAGE_SIZE)
645 return -1;
646 memcpy(p, o->data, o->len);
647 memset(p + o->len, 0, round_up_to_quad(o->len) - o->len);
648 return 0;
649}
650
651/*
652 * Verify the checksum on the header and return SVC_OK on success.
653 * Otherwise, return SVC_DROP (in the case of a bad sequence number)
654 * or return SVC_DENIED and indicate error in authp.
655 */
656static int
657gss_verify_header(struct svc_rqst *rqstp, struct rsc *rsci,
658 __be32 *rpcstart, struct rpc_gss_wire_cred *gc, __be32 *authp)
659{
660 struct gss_ctx *ctx_id = rsci->mechctx;
661 struct xdr_buf rpchdr;
662 struct xdr_netobj checksum;
663 u32 flavor = 0;
664 struct kvec *argv = &rqstp->rq_arg.head[0];
665 struct kvec iov;
666
667 /* data to compute the checksum over: */
668 iov.iov_base = rpcstart;
669 iov.iov_len = (u8 *)argv->iov_base - (u8 *)rpcstart;
670 xdr_buf_from_iov(&iov, &rpchdr);
671
672 *authp = rpc_autherr_badverf;
673 if (argv->iov_len < 4)
674 return SVC_DENIED;
675 flavor = svc_getnl(argv);
676 if (flavor != RPC_AUTH_GSS)
677 return SVC_DENIED;
678 if (svc_safe_getnetobj(argv, &checksum))
679 return SVC_DENIED;
680
681 if (rqstp->rq_deferred) /* skip verification of revisited request */
682 return SVC_OK;
683 if (gss_verify_mic(ctx_id, &rpchdr, &checksum) != GSS_S_COMPLETE) {
684 *authp = rpcsec_gsserr_credproblem;
685 return SVC_DENIED;
686 }
687
688 if (gc->gc_seq > MAXSEQ) {
689 dprintk("RPC: svcauth_gss: discarding request with "
690 "large sequence number %d\n", gc->gc_seq);
691 *authp = rpcsec_gsserr_ctxproblem;
692 return SVC_DENIED;
693 }
694 if (!gss_check_seq_num(rsci, gc->gc_seq)) {
695 dprintk("RPC: svcauth_gss: discarding request with "
696 "old sequence number %d\n", gc->gc_seq);
697 return SVC_DROP;
698 }
699 return SVC_OK;
700}
701
702static int
703gss_write_null_verf(struct svc_rqst *rqstp)
704{
705 __be32 *p;
706
707 svc_putnl(rqstp->rq_res.head, RPC_AUTH_NULL);
708 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len;
709 /* don't really need to check if head->iov_len > PAGE_SIZE ... */
710 *p++ = 0;
711 if (!xdr_ressize_check(rqstp, p))
712 return -1;
713 return 0;
714}
715
716static int
717gss_write_verf(struct svc_rqst *rqstp, struct gss_ctx *ctx_id, u32 seq)
718{
719 __be32 xdr_seq;
720 u32 maj_stat;
721 struct xdr_buf verf_data;
722 struct xdr_netobj mic;
723 __be32 *p;
724 struct kvec iov;
725
726 svc_putnl(rqstp->rq_res.head, RPC_AUTH_GSS);
727 xdr_seq = htonl(seq);
728
729 iov.iov_base = &xdr_seq;
730 iov.iov_len = sizeof(xdr_seq);
731 xdr_buf_from_iov(&iov, &verf_data);
732 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len;
733 mic.data = (u8 *)(p + 1);
734 maj_stat = gss_get_mic(ctx_id, &verf_data, &mic);
735 if (maj_stat != GSS_S_COMPLETE)
736 return -1;
737 *p++ = htonl(mic.len);
738 memset((u8 *)p + mic.len, 0, round_up_to_quad(mic.len) - mic.len);
739 p += XDR_QUADLEN(mic.len);
740 if (!xdr_ressize_check(rqstp, p))
741 return -1;
742 return 0;
743}
744
745struct gss_domain {
746 struct auth_domain h;
747 u32 pseudoflavor;
748};
749
750static struct auth_domain *
751find_gss_auth_domain(struct gss_ctx *ctx, u32 svc)
752{
753 char *name;
754
755 name = gss_service_to_auth_domain_name(ctx->mech_type, svc);
756 if (!name)
757 return NULL;
758 return auth_domain_find(name);
759}
760
761static struct auth_ops svcauthops_gss;
762
763u32 svcauth_gss_flavor(struct auth_domain *dom)
764{
765 struct gss_domain *gd = container_of(dom, struct gss_domain, h);
766
767 return gd->pseudoflavor;
768}
769
770EXPORT_SYMBOL_GPL(svcauth_gss_flavor);
771
772int
773svcauth_gss_register_pseudoflavor(u32 pseudoflavor, char * name)
774{
775 struct gss_domain *new;
776 struct auth_domain *test;
777 int stat = -ENOMEM;
778
779 new = kmalloc(sizeof(*new), GFP_KERNEL);
780 if (!new)
781 goto out;
782 kref_init(&new->h.ref);
783 new->h.name = kstrdup(name, GFP_KERNEL);
784 if (!new->h.name)
785 goto out_free_dom;
786 new->h.flavour = &svcauthops_gss;
787 new->pseudoflavor = pseudoflavor;
788
789 stat = 0;
790 test = auth_domain_lookup(name, &new->h);
791 if (test != &new->h) { /* Duplicate registration */
792 auth_domain_put(test);
793 kfree(new->h.name);
794 goto out_free_dom;
795 }
796 return 0;
797
798out_free_dom:
799 kfree(new);
800out:
801 return stat;
802}
803
804EXPORT_SYMBOL_GPL(svcauth_gss_register_pseudoflavor);
805
806static inline int
807read_u32_from_xdr_buf(struct xdr_buf *buf, int base, u32 *obj)
808{
809 __be32 raw;
810 int status;
811
812 status = read_bytes_from_xdr_buf(buf, base, &raw, sizeof(*obj));
813 if (status)
814 return status;
815 *obj = ntohl(raw);
816 return 0;
817}
818
819/* It would be nice if this bit of code could be shared with the client.
820 * Obstacles:
821 * The client shouldn't malloc(), would have to pass in own memory.
822 * The server uses base of head iovec as read pointer, while the
823 * client uses separate pointer. */
824static int
825unwrap_integ_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx)
826{
827 int stat = -EINVAL;
828 u32 integ_len, maj_stat;
829 struct xdr_netobj mic;
830 struct xdr_buf integ_buf;
831
832 /* Did we already verify the signature on the original pass through? */
833 if (rqstp->rq_deferred)
834 return 0;
835
836 integ_len = svc_getnl(&buf->head[0]);
837 if (integ_len & 3)
838 return stat;
839 if (integ_len > buf->len)
840 return stat;
841 if (xdr_buf_subsegment(buf, &integ_buf, 0, integ_len))
842 BUG();
843 /* copy out mic... */
844 if (read_u32_from_xdr_buf(buf, integ_len, &mic.len))
845 BUG();
846 if (mic.len > RPC_MAX_AUTH_SIZE)
847 return stat;
848 mic.data = kmalloc(mic.len, GFP_KERNEL);
849 if (!mic.data)
850 return stat;
851 if (read_bytes_from_xdr_buf(buf, integ_len + 4, mic.data, mic.len))
852 goto out;
853 maj_stat = gss_verify_mic(ctx, &integ_buf, &mic);
854 if (maj_stat != GSS_S_COMPLETE)
855 goto out;
856 if (svc_getnl(&buf->head[0]) != seq)
857 goto out;
858 /* trim off the mic at the end before returning */
859 xdr_buf_trim(buf, mic.len + 4);
860 stat = 0;
861out:
862 kfree(mic.data);
863 return stat;
864}
865
866static inline int
867total_buf_len(struct xdr_buf *buf)
868{
869 return buf->head[0].iov_len + buf->page_len + buf->tail[0].iov_len;
870}
871
872static void
873fix_priv_head(struct xdr_buf *buf, int pad)
874{
875 if (buf->page_len == 0) {
876 /* We need to adjust head and buf->len in tandem in this
877 * case to make svc_defer() work--it finds the original
878 * buffer start using buf->len - buf->head[0].iov_len. */
879 buf->head[0].iov_len -= pad;
880 }
881}
882
883static int
884unwrap_priv_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx)
885{
886 u32 priv_len, maj_stat;
887 int pad, saved_len, remaining_len, offset;
888
889 rqstp->rq_splice_ok = 0;
890
891 priv_len = svc_getnl(&buf->head[0]);
892 if (rqstp->rq_deferred) {
893 /* Already decrypted last time through! The sequence number
894 * check at out_seq is unnecessary but harmless: */
895 goto out_seq;
896 }
897 /* buf->len is the number of bytes from the original start of the
898 * request to the end, where head[0].iov_len is just the bytes
899 * not yet read from the head, so these two values are different: */
900 remaining_len = total_buf_len(buf);
901 if (priv_len > remaining_len)
902 return -EINVAL;
903 pad = remaining_len - priv_len;
904 buf->len -= pad;
905 fix_priv_head(buf, pad);
906
907 /* Maybe it would be better to give gss_unwrap a length parameter: */
908 saved_len = buf->len;
909 buf->len = priv_len;
910 maj_stat = gss_unwrap(ctx, 0, buf);
911 pad = priv_len - buf->len;
912 buf->len = saved_len;
913 buf->len -= pad;
914 /* The upper layers assume the buffer is aligned on 4-byte boundaries.
915 * In the krb5p case, at least, the data ends up offset, so we need to
916 * move it around. */
917 /* XXX: This is very inefficient. It would be better to either do
918 * this while we encrypt, or maybe in the receive code, if we can peak
919 * ahead and work out the service and mechanism there. */
920 offset = buf->head[0].iov_len % 4;
921 if (offset) {
922 buf->buflen = RPCSVC_MAXPAYLOAD;
923 xdr_shift_buf(buf, offset);
924 fix_priv_head(buf, pad);
925 }
926 if (maj_stat != GSS_S_COMPLETE)
927 return -EINVAL;
928out_seq:
929 if (svc_getnl(&buf->head[0]) != seq)
930 return -EINVAL;
931 return 0;
932}
933
934struct gss_svc_data {
935 /* decoded gss client cred: */
936 struct rpc_gss_wire_cred clcred;
937 /* save a pointer to the beginning of the encoded verifier,
938 * for use in encryption/checksumming in svcauth_gss_release: */
939 __be32 *verf_start;
940 struct rsc *rsci;
941};
942
943static int
944svcauth_gss_set_client(struct svc_rqst *rqstp)
945{
946 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
947 struct rsc *rsci = svcdata->rsci;
948 struct rpc_gss_wire_cred *gc = &svcdata->clcred;
949 int stat;
950
951 /*
952 * A gss export can be specified either by:
953 * export *(sec=krb5,rw)
954 * or by
955 * export gss/krb5(rw)
956 * The latter is deprecated; but for backwards compatibility reasons
957 * the nfsd code will still fall back on trying it if the former
958 * doesn't work; so we try to make both available to nfsd, below.
959 */
960 rqstp->rq_gssclient = find_gss_auth_domain(rsci->mechctx, gc->gc_svc);
961 if (rqstp->rq_gssclient == NULL)
962 return SVC_DENIED;
963 stat = svcauth_unix_set_client(rqstp);
964 if (stat == SVC_DROP || stat == SVC_CLOSE)
965 return stat;
966 return SVC_OK;
967}
968
969static inline int
970gss_write_init_verf(struct cache_detail *cd, struct svc_rqst *rqstp,
971 struct xdr_netobj *out_handle, int *major_status)
972{
973 struct rsc *rsci;
974 int rc;
975
976 if (*major_status != GSS_S_COMPLETE)
977 return gss_write_null_verf(rqstp);
978 rsci = gss_svc_searchbyctx(cd, out_handle);
979 if (rsci == NULL) {
980 *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, cd);
985 return rc;
986}
987
988static inline int
989gss_read_common_verf(struct rpc_gss_wire_cred *gc,
990 struct kvec *argv, __be32 *authp,
991 struct xdr_netobj *in_handle)
992{
993 /* Read the verifier; should be NULL: */
994 *authp = rpc_autherr_badverf;
995 if (argv->iov_len < 2 * 4)
996 return SVC_DENIED;
997 if (svc_getnl(argv) != RPC_AUTH_NULL)
998 return SVC_DENIED;
999 if (svc_getnl(argv) != 0)
1000 return SVC_DENIED;
1001 /* Martial context handle and token for upcall: */
1002 *authp = rpc_autherr_badcred;
1003 if (gc->gc_proc == RPC_GSS_PROC_INIT && gc->gc_ctx.len != 0)
1004 return SVC_DENIED;
1005 if (dup_netobj(in_handle, &gc->gc_ctx))
1006 return SVC_CLOSE;
1007 *authp = rpc_autherr_badverf;
1008
1009 return 0;
1010}
1011
1012static inline int
1013gss_read_verf(struct rpc_gss_wire_cred *gc,
1014 struct kvec *argv, __be32 *authp,
1015 struct xdr_netobj *in_handle,
1016 struct xdr_netobj *in_token)
1017{
1018 struct xdr_netobj tmpobj;
1019 int res;
1020
1021 res = gss_read_common_verf(gc, argv, authp, in_handle);
1022 if (res)
1023 return res;
1024
1025 if (svc_safe_getnetobj(argv, &tmpobj)) {
1026 kfree(in_handle->data);
1027 return SVC_DENIED;
1028 }
1029 if (dup_netobj(in_token, &tmpobj)) {
1030 kfree(in_handle->data);
1031 return SVC_CLOSE;
1032 }
1033
1034 return 0;
1035}
1036
1037/* Ok this is really heavily depending on a set of semantics in
1038 * how rqstp is set up by svc_recv and pages laid down by the
1039 * server when reading a request. We are basically guaranteed that
1040 * the token lays all down linearly across a set of pages, starting
1041 * at iov_base in rq_arg.head[0] which happens to be the first of a
1042 * set of pages stored in rq_pages[].
1043 * rq_arg.head[0].iov_base will provide us the page_base to pass
1044 * to the upcall.
1045 */
1046static inline int
1047gss_read_proxy_verf(struct svc_rqst *rqstp,
1048 struct rpc_gss_wire_cred *gc, __be32 *authp,
1049 struct xdr_netobj *in_handle,
1050 struct gssp_in_token *in_token)
1051{
1052 struct kvec *argv = &rqstp->rq_arg.head[0];
1053 u32 inlen;
1054 int res;
1055
1056 res = gss_read_common_verf(gc, argv, authp, in_handle);
1057 if (res)
1058 return res;
1059
1060 inlen = svc_getnl(argv);
1061 if (inlen > (argv->iov_len + rqstp->rq_arg.page_len))
1062 return SVC_DENIED;
1063
1064 in_token->pages = rqstp->rq_pages;
1065 in_token->page_base = (ulong)argv->iov_base & ~PAGE_MASK;
1066 in_token->page_len = inlen;
1067
1068 return 0;
1069}
1070
1071static inline int
1072gss_write_resv(struct kvec *resv, size_t size_limit,
1073 struct xdr_netobj *out_handle, struct xdr_netobj *out_token,
1074 int major_status, int minor_status)
1075{
1076 if (resv->iov_len + 4 > size_limit)
1077 return -1;
1078 svc_putnl(resv, RPC_SUCCESS);
1079 if (svc_safe_putnetobj(resv, out_handle))
1080 return -1;
1081 if (resv->iov_len + 3 * 4 > size_limit)
1082 return -1;
1083 svc_putnl(resv, major_status);
1084 svc_putnl(resv, minor_status);
1085 svc_putnl(resv, GSS_SEQ_WIN);
1086 if (svc_safe_putnetobj(resv, out_token))
1087 return -1;
1088 return 0;
1089}
1090
1091/*
1092 * Having read the cred already and found we're in the context
1093 * initiation case, read the verifier and initiate (or check the results
1094 * of) upcalls to userspace for help with context initiation. If
1095 * the upcall results are available, write the verifier and result.
1096 * Otherwise, drop the request pending an answer to the upcall.
1097 */
1098static int svcauth_gss_legacy_init(struct svc_rqst *rqstp,
1099 struct rpc_gss_wire_cred *gc, __be32 *authp)
1100{
1101 struct kvec *argv = &rqstp->rq_arg.head[0];
1102 struct kvec *resv = &rqstp->rq_res.head[0];
1103 struct rsi *rsip, rsikey;
1104 int ret;
1105 struct sunrpc_net *sn = net_generic(rqstp->rq_xprt->xpt_net, sunrpc_net_id);
1106
1107 memset(&rsikey, 0, sizeof(rsikey));
1108 ret = gss_read_verf(gc, argv, authp,
1109 &rsikey.in_handle, &rsikey.in_token);
1110 if (ret)
1111 return ret;
1112
1113 /* Perform upcall, or find upcall result: */
1114 rsip = rsi_lookup(sn->rsi_cache, &rsikey);
1115 rsi_free(&rsikey);
1116 if (!rsip)
1117 return SVC_CLOSE;
1118 if (cache_check(sn->rsi_cache, &rsip->h, &rqstp->rq_chandle) < 0)
1119 /* No upcall result: */
1120 return SVC_CLOSE;
1121
1122 ret = SVC_CLOSE;
1123 /* Got an answer to the upcall; use it: */
1124 if (gss_write_init_verf(sn->rsc_cache, rqstp,
1125 &rsip->out_handle, &rsip->major_status))
1126 goto out;
1127 if (gss_write_resv(resv, PAGE_SIZE,
1128 &rsip->out_handle, &rsip->out_token,
1129 rsip->major_status, rsip->minor_status))
1130 goto out;
1131
1132 ret = SVC_COMPLETE;
1133out:
1134 cache_put(&rsip->h, sn->rsi_cache);
1135 return ret;
1136}
1137
1138static int gss_proxy_save_rsc(struct cache_detail *cd,
1139 struct gssp_upcall_data *ud,
1140 uint64_t *handle)
1141{
1142 struct rsc rsci, *rscp = NULL;
1143 static atomic64_t ctxhctr;
1144 long long ctxh;
1145 struct gss_api_mech *gm = NULL;
1146 time_t expiry;
1147 int status = -EINVAL;
1148
1149 memset(&rsci, 0, sizeof(rsci));
1150 /* context handle */
1151 status = -ENOMEM;
1152 /* the handle needs to be just a unique id,
1153 * use a static counter */
1154 ctxh = atomic64_inc_return(&ctxhctr);
1155
1156 /* make a copy for the caller */
1157 *handle = ctxh;
1158
1159 /* make a copy for the rsc cache */
1160 if (dup_to_netobj(&rsci.handle, (char *)handle, sizeof(uint64_t)))
1161 goto out;
1162 rscp = rsc_lookup(cd, &rsci);
1163 if (!rscp)
1164 goto out;
1165
1166 /* creds */
1167 if (!ud->found_creds) {
1168 /* userspace seem buggy, we should always get at least a
1169 * mapping to nobody */
1170 dprintk("RPC: No creds found!\n");
1171 goto out;
1172 } else {
1173
1174 /* steal creds */
1175 rsci.cred = ud->creds;
1176 memset(&ud->creds, 0, sizeof(struct svc_cred));
1177
1178 status = -EOPNOTSUPP;
1179 /* get mech handle from OID */
1180 gm = gss_mech_get_by_OID(&ud->mech_oid);
1181 if (!gm)
1182 goto out;
1183 rsci.cred.cr_gss_mech = gm;
1184
1185 status = -EINVAL;
1186 /* mech-specific data: */
1187 status = gss_import_sec_context(ud->out_handle.data,
1188 ud->out_handle.len,
1189 gm, &rsci.mechctx,
1190 &expiry, GFP_KERNEL);
1191 if (status)
1192 goto out;
1193 }
1194
1195 rsci.h.expiry_time = expiry;
1196 rscp = rsc_update(cd, &rsci, rscp);
1197 status = 0;
1198out:
1199 rsc_free(&rsci);
1200 if (rscp)
1201 cache_put(&rscp->h, cd);
1202 else
1203 status = -ENOMEM;
1204 return status;
1205}
1206
1207static int svcauth_gss_proxy_init(struct svc_rqst *rqstp,
1208 struct rpc_gss_wire_cred *gc, __be32 *authp)
1209{
1210 struct kvec *resv = &rqstp->rq_res.head[0];
1211 struct xdr_netobj cli_handle;
1212 struct gssp_upcall_data ud;
1213 uint64_t handle;
1214 int status;
1215 int ret;
1216 struct net *net = rqstp->rq_xprt->xpt_net;
1217 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1218
1219 memset(&ud, 0, sizeof(ud));
1220 ret = gss_read_proxy_verf(rqstp, gc, authp,
1221 &ud.in_handle, &ud.in_token);
1222 if (ret)
1223 return ret;
1224
1225 ret = SVC_CLOSE;
1226
1227 /* Perform synchronous upcall to gss-proxy */
1228 status = gssp_accept_sec_context_upcall(net, &ud);
1229 if (status)
1230 goto out;
1231
1232 dprintk("RPC: svcauth_gss: gss major status = %d\n",
1233 ud.major_status);
1234
1235 switch (ud.major_status) {
1236 case GSS_S_CONTINUE_NEEDED:
1237 cli_handle = ud.out_handle;
1238 break;
1239 case GSS_S_COMPLETE:
1240 status = gss_proxy_save_rsc(sn->rsc_cache, &ud, &handle);
1241 if (status)
1242 goto out;
1243 cli_handle.data = (u8 *)&handle;
1244 cli_handle.len = sizeof(handle);
1245 break;
1246 default:
1247 ret = SVC_CLOSE;
1248 goto out;
1249 }
1250
1251 /* Got an answer to the upcall; use it: */
1252 if (gss_write_init_verf(sn->rsc_cache, rqstp,
1253 &cli_handle, &ud.major_status))
1254 goto out;
1255 if (gss_write_resv(resv, PAGE_SIZE,
1256 &cli_handle, &ud.out_token,
1257 ud.major_status, ud.minor_status))
1258 goto out;
1259
1260 ret = SVC_COMPLETE;
1261out:
1262 gssp_free_upcall_data(&ud);
1263 return ret;
1264}
1265
1266/*
1267 * Try to set the sn->use_gss_proxy variable to a new value. We only allow
1268 * it to be changed if it's currently undefined (-1). If it's any other value
1269 * then return -EBUSY unless the type wouldn't have changed anyway.
1270 */
1271static int set_gss_proxy(struct net *net, int type)
1272{
1273 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1274 int ret;
1275
1276 WARN_ON_ONCE(type != 0 && type != 1);
1277 ret = cmpxchg(&sn->use_gss_proxy, -1, type);
1278 if (ret != -1 && ret != type)
1279 return -EBUSY;
1280 return 0;
1281}
1282
1283static bool use_gss_proxy(struct net *net)
1284{
1285 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1286
1287 /* If use_gss_proxy is still undefined, then try to disable it */
1288 if (sn->use_gss_proxy == -1)
1289 set_gss_proxy(net, 0);
1290 return sn->use_gss_proxy;
1291}
1292
1293#ifdef CONFIG_PROC_FS
1294
1295static ssize_t write_gssp(struct file *file, const char __user *buf,
1296 size_t count, loff_t *ppos)
1297{
1298 struct net *net = PDE_DATA(file_inode(file));
1299 char tbuf[20];
1300 unsigned long i;
1301 int res;
1302
1303 if (*ppos || count > sizeof(tbuf)-1)
1304 return -EINVAL;
1305 if (copy_from_user(tbuf, buf, count))
1306 return -EFAULT;
1307
1308 tbuf[count] = 0;
1309 res = kstrtoul(tbuf, 0, &i);
1310 if (res)
1311 return res;
1312 if (i != 1)
1313 return -EINVAL;
1314 res = set_gssp_clnt(net);
1315 if (res)
1316 return res;
1317 res = set_gss_proxy(net, 1);
1318 if (res)
1319 return res;
1320 return count;
1321}
1322
1323static ssize_t read_gssp(struct file *file, char __user *buf,
1324 size_t count, loff_t *ppos)
1325{
1326 struct net *net = PDE_DATA(file_inode(file));
1327 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1328 unsigned long p = *ppos;
1329 char tbuf[10];
1330 size_t len;
1331
1332 snprintf(tbuf, sizeof(tbuf), "%d\n", sn->use_gss_proxy);
1333 len = strlen(tbuf);
1334 if (p >= len)
1335 return 0;
1336 len -= p;
1337 if (len > count)
1338 len = count;
1339 if (copy_to_user(buf, (void *)(tbuf+p), len))
1340 return -EFAULT;
1341 *ppos += len;
1342 return len;
1343}
1344
1345static const struct file_operations use_gss_proxy_ops = {
1346 .open = nonseekable_open,
1347 .write = write_gssp,
1348 .read = read_gssp,
1349};
1350
1351static int create_use_gss_proxy_proc_entry(struct net *net)
1352{
1353 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1354 struct proc_dir_entry **p = &sn->use_gssp_proc;
1355
1356 sn->use_gss_proxy = -1;
1357 *p = proc_create_data("use-gss-proxy", S_IFREG|S_IRUSR|S_IWUSR,
1358 sn->proc_net_rpc,
1359 &use_gss_proxy_ops, net);
1360 if (!*p)
1361 return -ENOMEM;
1362 init_gssp_clnt(sn);
1363 return 0;
1364}
1365
1366static void destroy_use_gss_proxy_proc_entry(struct net *net)
1367{
1368 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1369
1370 if (sn->use_gssp_proc) {
1371 remove_proc_entry("use-gss-proxy", sn->proc_net_rpc);
1372 clear_gssp_clnt(sn);
1373 }
1374}
1375#else /* CONFIG_PROC_FS */
1376
1377static int create_use_gss_proxy_proc_entry(struct net *net)
1378{
1379 return 0;
1380}
1381
1382static void destroy_use_gss_proxy_proc_entry(struct net *net) {}
1383
1384#endif /* CONFIG_PROC_FS */
1385
1386/*
1387 * Accept an rpcsec packet.
1388 * If context establishment, punt to user space
1389 * If data exchange, verify/decrypt
1390 * If context destruction, handle here
1391 * In the context establishment and destruction case we encode
1392 * response here and return SVC_COMPLETE.
1393 */
1394static int
1395svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
1396{
1397 struct kvec *argv = &rqstp->rq_arg.head[0];
1398 struct kvec *resv = &rqstp->rq_res.head[0];
1399 u32 crlen;
1400 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
1401 struct rpc_gss_wire_cred *gc;
1402 struct rsc *rsci = NULL;
1403 __be32 *rpcstart;
1404 __be32 *reject_stat = resv->iov_base + resv->iov_len;
1405 int ret;
1406 struct sunrpc_net *sn = net_generic(rqstp->rq_xprt->xpt_net, sunrpc_net_id);
1407
1408 dprintk("RPC: svcauth_gss: argv->iov_len = %zd\n",
1409 argv->iov_len);
1410
1411 *authp = rpc_autherr_badcred;
1412 if (!svcdata)
1413 svcdata = kmalloc(sizeof(*svcdata), GFP_KERNEL);
1414 if (!svcdata)
1415 goto auth_err;
1416 rqstp->rq_auth_data = svcdata;
1417 svcdata->verf_start = NULL;
1418 svcdata->rsci = NULL;
1419 gc = &svcdata->clcred;
1420
1421 /* start of rpc packet is 7 u32's back from here:
1422 * xid direction rpcversion prog vers proc flavour
1423 */
1424 rpcstart = argv->iov_base;
1425 rpcstart -= 7;
1426
1427 /* credential is:
1428 * version(==1), proc(0,1,2,3), seq, service (1,2,3), handle
1429 * at least 5 u32s, and is preceded by length, so that makes 6.
1430 */
1431
1432 if (argv->iov_len < 5 * 4)
1433 goto auth_err;
1434 crlen = svc_getnl(argv);
1435 if (svc_getnl(argv) != RPC_GSS_VERSION)
1436 goto auth_err;
1437 gc->gc_proc = svc_getnl(argv);
1438 gc->gc_seq = svc_getnl(argv);
1439 gc->gc_svc = svc_getnl(argv);
1440 if (svc_safe_getnetobj(argv, &gc->gc_ctx))
1441 goto auth_err;
1442 if (crlen != round_up_to_quad(gc->gc_ctx.len) + 5 * 4)
1443 goto auth_err;
1444
1445 if ((gc->gc_proc != RPC_GSS_PROC_DATA) && (rqstp->rq_proc != 0))
1446 goto auth_err;
1447
1448 *authp = rpc_autherr_badverf;
1449 switch (gc->gc_proc) {
1450 case RPC_GSS_PROC_INIT:
1451 case RPC_GSS_PROC_CONTINUE_INIT:
1452 if (use_gss_proxy(SVC_NET(rqstp)))
1453 return svcauth_gss_proxy_init(rqstp, gc, authp);
1454 else
1455 return svcauth_gss_legacy_init(rqstp, gc, authp);
1456 case RPC_GSS_PROC_DATA:
1457 case RPC_GSS_PROC_DESTROY:
1458 /* Look up the context, and check the verifier: */
1459 *authp = rpcsec_gsserr_credproblem;
1460 rsci = gss_svc_searchbyctx(sn->rsc_cache, &gc->gc_ctx);
1461 if (!rsci)
1462 goto auth_err;
1463 switch (gss_verify_header(rqstp, rsci, rpcstart, gc, authp)) {
1464 case SVC_OK:
1465 break;
1466 case SVC_DENIED:
1467 goto auth_err;
1468 case SVC_DROP:
1469 goto drop;
1470 }
1471 break;
1472 default:
1473 *authp = rpc_autherr_rejectedcred;
1474 goto auth_err;
1475 }
1476
1477 /* now act upon the command: */
1478 switch (gc->gc_proc) {
1479 case RPC_GSS_PROC_DESTROY:
1480 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
1481 goto auth_err;
1482 rsci->h.expiry_time = get_seconds();
1483 set_bit(CACHE_NEGATIVE, &rsci->h.flags);
1484 if (resv->iov_len + 4 > PAGE_SIZE)
1485 goto drop;
1486 svc_putnl(resv, RPC_SUCCESS);
1487 goto complete;
1488 case RPC_GSS_PROC_DATA:
1489 *authp = rpcsec_gsserr_ctxproblem;
1490 svcdata->verf_start = resv->iov_base + resv->iov_len;
1491 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
1492 goto auth_err;
1493 rqstp->rq_cred = rsci->cred;
1494 get_group_info(rsci->cred.cr_group_info);
1495 *authp = rpc_autherr_badcred;
1496 switch (gc->gc_svc) {
1497 case RPC_GSS_SVC_NONE:
1498 break;
1499 case RPC_GSS_SVC_INTEGRITY:
1500 /* placeholders for length and seq. number: */
1501 svc_putnl(resv, 0);
1502 svc_putnl(resv, 0);
1503 if (unwrap_integ_data(rqstp, &rqstp->rq_arg,
1504 gc->gc_seq, rsci->mechctx))
1505 goto garbage_args;
1506 break;
1507 case RPC_GSS_SVC_PRIVACY:
1508 /* placeholders for length and seq. number: */
1509 svc_putnl(resv, 0);
1510 svc_putnl(resv, 0);
1511 if (unwrap_priv_data(rqstp, &rqstp->rq_arg,
1512 gc->gc_seq, rsci->mechctx))
1513 goto garbage_args;
1514 break;
1515 default:
1516 goto auth_err;
1517 }
1518 svcdata->rsci = rsci;
1519 cache_get(&rsci->h);
1520 rqstp->rq_cred.cr_flavor = gss_svc_to_pseudoflavor(
1521 rsci->mechctx->mech_type,
1522 GSS_C_QOP_DEFAULT,
1523 gc->gc_svc);
1524 ret = SVC_OK;
1525 goto out;
1526 }
1527garbage_args:
1528 ret = SVC_GARBAGE;
1529 goto out;
1530auth_err:
1531 /* Restore write pointer to its original value: */
1532 xdr_ressize_check(rqstp, reject_stat);
1533 ret = SVC_DENIED;
1534 goto out;
1535complete:
1536 ret = SVC_COMPLETE;
1537 goto out;
1538drop:
1539 ret = SVC_DROP;
1540out:
1541 if (rsci)
1542 cache_put(&rsci->h, sn->rsc_cache);
1543 return ret;
1544}
1545
1546static __be32 *
1547svcauth_gss_prepare_to_wrap(struct xdr_buf *resbuf, struct gss_svc_data *gsd)
1548{
1549 __be32 *p;
1550 u32 verf_len;
1551
1552 p = gsd->verf_start;
1553 gsd->verf_start = NULL;
1554
1555 /* If the reply stat is nonzero, don't wrap: */
1556 if (*(p-1) != rpc_success)
1557 return NULL;
1558 /* Skip the verifier: */
1559 p += 1;
1560 verf_len = ntohl(*p++);
1561 p += XDR_QUADLEN(verf_len);
1562 /* move accept_stat to right place: */
1563 memcpy(p, p + 2, 4);
1564 /* Also don't wrap if the accept stat is nonzero: */
1565 if (*p != rpc_success) {
1566 resbuf->head[0].iov_len -= 2 * 4;
1567 return NULL;
1568 }
1569 p++;
1570 return p;
1571}
1572
1573static inline int
1574svcauth_gss_wrap_resp_integ(struct svc_rqst *rqstp)
1575{
1576 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1577 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1578 struct xdr_buf *resbuf = &rqstp->rq_res;
1579 struct xdr_buf integ_buf;
1580 struct xdr_netobj mic;
1581 struct kvec *resv;
1582 __be32 *p;
1583 int integ_offset, integ_len;
1584 int stat = -EINVAL;
1585
1586 p = svcauth_gss_prepare_to_wrap(resbuf, gsd);
1587 if (p == NULL)
1588 goto out;
1589 integ_offset = (u8 *)(p + 1) - (u8 *)resbuf->head[0].iov_base;
1590 integ_len = resbuf->len - integ_offset;
1591 BUG_ON(integ_len % 4);
1592 *p++ = htonl(integ_len);
1593 *p++ = htonl(gc->gc_seq);
1594 if (xdr_buf_subsegment(resbuf, &integ_buf, integ_offset, integ_len))
1595 BUG();
1596 if (resbuf->tail[0].iov_base == NULL) {
1597 if (resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1598 goto out_err;
1599 resbuf->tail[0].iov_base = resbuf->head[0].iov_base
1600 + resbuf->head[0].iov_len;
1601 resbuf->tail[0].iov_len = 0;
1602 }
1603 resv = &resbuf->tail[0];
1604 mic.data = (u8 *)resv->iov_base + resv->iov_len + 4;
1605 if (gss_get_mic(gsd->rsci->mechctx, &integ_buf, &mic))
1606 goto out_err;
1607 svc_putnl(resv, mic.len);
1608 memset(mic.data + mic.len, 0,
1609 round_up_to_quad(mic.len) - mic.len);
1610 resv->iov_len += XDR_QUADLEN(mic.len) << 2;
1611 /* not strictly required: */
1612 resbuf->len += XDR_QUADLEN(mic.len) << 2;
1613 BUG_ON(resv->iov_len > PAGE_SIZE);
1614out:
1615 stat = 0;
1616out_err:
1617 return stat;
1618}
1619
1620static inline int
1621svcauth_gss_wrap_resp_priv(struct svc_rqst *rqstp)
1622{
1623 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1624 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1625 struct xdr_buf *resbuf = &rqstp->rq_res;
1626 struct page **inpages = NULL;
1627 __be32 *p, *len;
1628 int offset;
1629 int pad;
1630
1631 p = svcauth_gss_prepare_to_wrap(resbuf, gsd);
1632 if (p == NULL)
1633 return 0;
1634 len = p++;
1635 offset = (u8 *)p - (u8 *)resbuf->head[0].iov_base;
1636 *p++ = htonl(gc->gc_seq);
1637 inpages = resbuf->pages;
1638 /* XXX: Would be better to write some xdr helper functions for
1639 * nfs{2,3,4}xdr.c that place the data right, instead of copying: */
1640
1641 /*
1642 * If there is currently tail data, make sure there is
1643 * room for the head, tail, and 2 * RPC_MAX_AUTH_SIZE in
1644 * the page, and move the current tail data such that
1645 * there is RPC_MAX_AUTH_SIZE slack space available in
1646 * both the head and tail.
1647 */
1648 if (resbuf->tail[0].iov_base) {
1649 BUG_ON(resbuf->tail[0].iov_base >= resbuf->head[0].iov_base
1650 + PAGE_SIZE);
1651 BUG_ON(resbuf->tail[0].iov_base < resbuf->head[0].iov_base);
1652 if (resbuf->tail[0].iov_len + resbuf->head[0].iov_len
1653 + 2 * RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1654 return -ENOMEM;
1655 memmove(resbuf->tail[0].iov_base + RPC_MAX_AUTH_SIZE,
1656 resbuf->tail[0].iov_base,
1657 resbuf->tail[0].iov_len);
1658 resbuf->tail[0].iov_base += RPC_MAX_AUTH_SIZE;
1659 }
1660 /*
1661 * If there is no current tail data, make sure there is
1662 * room for the head data, and 2 * RPC_MAX_AUTH_SIZE in the
1663 * allotted page, and set up tail information such that there
1664 * is RPC_MAX_AUTH_SIZE slack space available in both the
1665 * head and tail.
1666 */
1667 if (resbuf->tail[0].iov_base == NULL) {
1668 if (resbuf->head[0].iov_len + 2*RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1669 return -ENOMEM;
1670 resbuf->tail[0].iov_base = resbuf->head[0].iov_base
1671 + resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE;
1672 resbuf->tail[0].iov_len = 0;
1673 }
1674 if (gss_wrap(gsd->rsci->mechctx, offset, resbuf, inpages))
1675 return -ENOMEM;
1676 *len = htonl(resbuf->len - offset);
1677 pad = 3 - ((resbuf->len - offset - 1)&3);
1678 p = (__be32 *)(resbuf->tail[0].iov_base + resbuf->tail[0].iov_len);
1679 memset(p, 0, pad);
1680 resbuf->tail[0].iov_len += pad;
1681 resbuf->len += pad;
1682 return 0;
1683}
1684
1685static int
1686svcauth_gss_release(struct svc_rqst *rqstp)
1687{
1688 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1689 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1690 struct xdr_buf *resbuf = &rqstp->rq_res;
1691 int stat = -EINVAL;
1692 struct sunrpc_net *sn = net_generic(rqstp->rq_xprt->xpt_net, sunrpc_net_id);
1693
1694 if (gc->gc_proc != RPC_GSS_PROC_DATA)
1695 goto out;
1696 /* Release can be called twice, but we only wrap once. */
1697 if (gsd->verf_start == NULL)
1698 goto out;
1699 /* normally not set till svc_send, but we need it here: */
1700 /* XXX: what for? Do we mess it up the moment we call svc_putu32
1701 * or whatever? */
1702 resbuf->len = total_buf_len(resbuf);
1703 switch (gc->gc_svc) {
1704 case RPC_GSS_SVC_NONE:
1705 break;
1706 case RPC_GSS_SVC_INTEGRITY:
1707 stat = svcauth_gss_wrap_resp_integ(rqstp);
1708 if (stat)
1709 goto out_err;
1710 break;
1711 case RPC_GSS_SVC_PRIVACY:
1712 stat = svcauth_gss_wrap_resp_priv(rqstp);
1713 if (stat)
1714 goto out_err;
1715 break;
1716 /*
1717 * For any other gc_svc value, svcauth_gss_accept() already set
1718 * the auth_error appropriately; just fall through:
1719 */
1720 }
1721
1722out:
1723 stat = 0;
1724out_err:
1725 if (rqstp->rq_client)
1726 auth_domain_put(rqstp->rq_client);
1727 rqstp->rq_client = NULL;
1728 if (rqstp->rq_gssclient)
1729 auth_domain_put(rqstp->rq_gssclient);
1730 rqstp->rq_gssclient = NULL;
1731 if (rqstp->rq_cred.cr_group_info)
1732 put_group_info(rqstp->rq_cred.cr_group_info);
1733 rqstp->rq_cred.cr_group_info = NULL;
1734 if (gsd->rsci)
1735 cache_put(&gsd->rsci->h, sn->rsc_cache);
1736 gsd->rsci = NULL;
1737
1738 return stat;
1739}
1740
1741static void
1742svcauth_gss_domain_release(struct auth_domain *dom)
1743{
1744 struct gss_domain *gd = container_of(dom, struct gss_domain, h);
1745
1746 kfree(dom->name);
1747 kfree(gd);
1748}
1749
1750static struct auth_ops svcauthops_gss = {
1751 .name = "rpcsec_gss",
1752 .owner = THIS_MODULE,
1753 .flavour = RPC_AUTH_GSS,
1754 .accept = svcauth_gss_accept,
1755 .release = svcauth_gss_release,
1756 .domain_release = svcauth_gss_domain_release,
1757 .set_client = svcauth_gss_set_client,
1758};
1759
1760static int rsi_cache_create_net(struct net *net)
1761{
1762 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1763 struct cache_detail *cd;
1764 int err;
1765
1766 cd = cache_create_net(&rsi_cache_template, net);
1767 if (IS_ERR(cd))
1768 return PTR_ERR(cd);
1769 err = cache_register_net(cd, net);
1770 if (err) {
1771 cache_destroy_net(cd, net);
1772 return err;
1773 }
1774 sn->rsi_cache = cd;
1775 return 0;
1776}
1777
1778static void rsi_cache_destroy_net(struct net *net)
1779{
1780 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1781 struct cache_detail *cd = sn->rsi_cache;
1782
1783 sn->rsi_cache = NULL;
1784 cache_purge(cd);
1785 cache_unregister_net(cd, net);
1786 cache_destroy_net(cd, net);
1787}
1788
1789static int rsc_cache_create_net(struct net *net)
1790{
1791 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1792 struct cache_detail *cd;
1793 int err;
1794
1795 cd = cache_create_net(&rsc_cache_template, net);
1796 if (IS_ERR(cd))
1797 return PTR_ERR(cd);
1798 err = cache_register_net(cd, net);
1799 if (err) {
1800 cache_destroy_net(cd, net);
1801 return err;
1802 }
1803 sn->rsc_cache = cd;
1804 return 0;
1805}
1806
1807static void rsc_cache_destroy_net(struct net *net)
1808{
1809 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1810 struct cache_detail *cd = sn->rsc_cache;
1811
1812 sn->rsc_cache = NULL;
1813 cache_purge(cd);
1814 cache_unregister_net(cd, net);
1815 cache_destroy_net(cd, net);
1816}
1817
1818int
1819gss_svc_init_net(struct net *net)
1820{
1821 int rv;
1822
1823 rv = rsc_cache_create_net(net);
1824 if (rv)
1825 return rv;
1826 rv = rsi_cache_create_net(net);
1827 if (rv)
1828 goto out1;
1829 rv = create_use_gss_proxy_proc_entry(net);
1830 if (rv)
1831 goto out2;
1832 return 0;
1833out2:
1834 destroy_use_gss_proxy_proc_entry(net);
1835out1:
1836 rsc_cache_destroy_net(net);
1837 return rv;
1838}
1839
1840void
1841gss_svc_shutdown_net(struct net *net)
1842{
1843 destroy_use_gss_proxy_proc_entry(net);
1844 rsi_cache_destroy_net(net);
1845 rsc_cache_destroy_net(net);
1846}
1847
1848int
1849gss_svc_init(void)
1850{
1851 return svc_auth_register(RPC_AUTH_GSS, &svcauthops_gss);
1852}
1853
1854void
1855gss_svc_shutdown(void)
1856{
1857 svc_auth_unregister(RPC_AUTH_GSS);
1858}