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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 u32 inlen;
1037 int i;
1038
1039 i = 0;
1040 inlen = in_token->page_len;
1041 while (inlen) {
1042 if (in_token->pages[i])
1043 put_page(in_token->pages[i]);
1044 inlen -= inlen > PAGE_SIZE ? PAGE_SIZE : inlen;
1045 }
1046
1047 kfree(in_token->pages);
1048 in_token->pages = NULL;
1049}
1050
1051static int gss_read_proxy_verf(struct svc_rqst *rqstp,
1052 struct rpc_gss_wire_cred *gc,
1053 struct xdr_netobj *in_handle,
1054 struct gssp_in_token *in_token)
1055{
1056 struct xdr_stream *xdr = &rqstp->rq_arg_stream;
1057 unsigned int length, pgto_offs, pgfrom_offs;
1058 int pages, i, pgto, pgfrom;
1059 size_t to_offs, from_offs;
1060 u32 inlen;
1061
1062 if (dup_netobj(in_handle, &gc->gc_ctx))
1063 return SVC_CLOSE;
1064
1065 /*
1066 * RFC 2203 Section 5.2.2
1067 *
1068 * struct rpc_gss_init_arg {
1069 * opaque gss_token<>;
1070 * };
1071 */
1072 if (xdr_stream_decode_u32(xdr, &inlen) < 0)
1073 goto out_denied_free;
1074 if (inlen > xdr_stream_remaining(xdr))
1075 goto out_denied_free;
1076
1077 pages = DIV_ROUND_UP(inlen, PAGE_SIZE);
1078 in_token->pages = kcalloc(pages, sizeof(struct page *), GFP_KERNEL);
1079 if (!in_token->pages)
1080 goto out_denied_free;
1081 in_token->page_base = 0;
1082 in_token->page_len = inlen;
1083 for (i = 0; i < pages; i++) {
1084 in_token->pages[i] = alloc_page(GFP_KERNEL);
1085 if (!in_token->pages[i]) {
1086 gss_free_in_token_pages(in_token);
1087 goto out_denied_free;
1088 }
1089 }
1090
1091 length = min_t(unsigned int, inlen, (char *)xdr->end - (char *)xdr->p);
1092 memcpy(page_address(in_token->pages[0]), xdr->p, length);
1093 inlen -= length;
1094
1095 to_offs = length;
1096 from_offs = rqstp->rq_arg.page_base;
1097 while (inlen) {
1098 pgto = to_offs >> PAGE_SHIFT;
1099 pgfrom = from_offs >> PAGE_SHIFT;
1100 pgto_offs = to_offs & ~PAGE_MASK;
1101 pgfrom_offs = from_offs & ~PAGE_MASK;
1102
1103 length = min_t(unsigned int, inlen,
1104 min_t(unsigned int, PAGE_SIZE - pgto_offs,
1105 PAGE_SIZE - pgfrom_offs));
1106 memcpy(page_address(in_token->pages[pgto]) + pgto_offs,
1107 page_address(rqstp->rq_arg.pages[pgfrom]) + pgfrom_offs,
1108 length);
1109
1110 to_offs += length;
1111 from_offs += length;
1112 inlen -= length;
1113 }
1114 return 0;
1115
1116out_denied_free:
1117 kfree(in_handle->data);
1118 return SVC_DENIED;
1119}
1120
1121/*
1122 * RFC 2203, Section 5.2.3.1.
1123 *
1124 * struct rpc_gss_init_res {
1125 * opaque handle<>;
1126 * unsigned int gss_major;
1127 * unsigned int gss_minor;
1128 * unsigned int seq_window;
1129 * opaque gss_token<>;
1130 * };
1131 */
1132static bool
1133svcxdr_encode_gss_init_res(struct xdr_stream *xdr,
1134 struct xdr_netobj *handle,
1135 struct xdr_netobj *gss_token,
1136 unsigned int major_status,
1137 unsigned int minor_status, u32 seq_num)
1138{
1139 if (xdr_stream_encode_opaque(xdr, handle->data, handle->len) < 0)
1140 return false;
1141 if (xdr_stream_encode_u32(xdr, major_status) < 0)
1142 return false;
1143 if (xdr_stream_encode_u32(xdr, minor_status) < 0)
1144 return false;
1145 if (xdr_stream_encode_u32(xdr, seq_num) < 0)
1146 return false;
1147 if (xdr_stream_encode_opaque(xdr, gss_token->data, gss_token->len) < 0)
1148 return false;
1149 return true;
1150}
1151
1152/*
1153 * Having read the cred already and found we're in the context
1154 * initiation case, read the verifier and initiate (or check the results
1155 * of) upcalls to userspace for help with context initiation. If
1156 * the upcall results are available, write the verifier and result.
1157 * Otherwise, drop the request pending an answer to the upcall.
1158 */
1159static int
1160svcauth_gss_legacy_init(struct svc_rqst *rqstp,
1161 struct rpc_gss_wire_cred *gc)
1162{
1163 struct xdr_stream *xdr = &rqstp->rq_arg_stream;
1164 struct rsi *rsip, rsikey;
1165 __be32 *p;
1166 u32 len;
1167 int ret;
1168 struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id);
1169
1170 memset(&rsikey, 0, sizeof(rsikey));
1171 if (dup_netobj(&rsikey.in_handle, &gc->gc_ctx))
1172 return SVC_CLOSE;
1173
1174 /*
1175 * RFC 2203 Section 5.2.2
1176 *
1177 * struct rpc_gss_init_arg {
1178 * opaque gss_token<>;
1179 * };
1180 */
1181 if (xdr_stream_decode_u32(xdr, &len) < 0) {
1182 kfree(rsikey.in_handle.data);
1183 return SVC_DENIED;
1184 }
1185 p = xdr_inline_decode(xdr, len);
1186 if (!p) {
1187 kfree(rsikey.in_handle.data);
1188 return SVC_DENIED;
1189 }
1190 rsikey.in_token.data = kmalloc(len, GFP_KERNEL);
1191 if (ZERO_OR_NULL_PTR(rsikey.in_token.data)) {
1192 kfree(rsikey.in_handle.data);
1193 return SVC_CLOSE;
1194 }
1195 memcpy(rsikey.in_token.data, p, len);
1196 rsikey.in_token.len = len;
1197
1198 /* Perform upcall, or find upcall result: */
1199 rsip = rsi_lookup(sn->rsi_cache, &rsikey);
1200 rsi_free(&rsikey);
1201 if (!rsip)
1202 return SVC_CLOSE;
1203 if (cache_check(sn->rsi_cache, &rsip->h, &rqstp->rq_chandle) < 0)
1204 /* No upcall result: */
1205 return SVC_CLOSE;
1206
1207 ret = SVC_CLOSE;
1208 if (!svcauth_gss_proc_init_verf(sn->rsc_cache, rqstp, &rsip->out_handle,
1209 &rsip->major_status, GSS_SEQ_WIN))
1210 goto out;
1211 if (!svcxdr_set_accept_stat(rqstp))
1212 goto out;
1213 if (!svcxdr_encode_gss_init_res(&rqstp->rq_res_stream, &rsip->out_handle,
1214 &rsip->out_token, rsip->major_status,
1215 rsip->minor_status, GSS_SEQ_WIN))
1216 goto out;
1217
1218 ret = SVC_COMPLETE;
1219out:
1220 cache_put(&rsip->h, sn->rsi_cache);
1221 return ret;
1222}
1223
1224static int gss_proxy_save_rsc(struct cache_detail *cd,
1225 struct gssp_upcall_data *ud,
1226 uint64_t *handle)
1227{
1228 struct rsc rsci, *rscp = NULL;
1229 static atomic64_t ctxhctr;
1230 long long ctxh;
1231 struct gss_api_mech *gm = NULL;
1232 time64_t expiry;
1233 int status;
1234
1235 memset(&rsci, 0, sizeof(rsci));
1236 /* context handle */
1237 status = -ENOMEM;
1238 /* the handle needs to be just a unique id,
1239 * use a static counter */
1240 ctxh = atomic64_inc_return(&ctxhctr);
1241
1242 /* make a copy for the caller */
1243 *handle = ctxh;
1244
1245 /* make a copy for the rsc cache */
1246 if (dup_to_netobj(&rsci.handle, (char *)handle, sizeof(uint64_t)))
1247 goto out;
1248 rscp = rsc_lookup(cd, &rsci);
1249 if (!rscp)
1250 goto out;
1251
1252 /* creds */
1253 if (!ud->found_creds) {
1254 /* userspace seem buggy, we should always get at least a
1255 * mapping to nobody */
1256 goto out;
1257 } else {
1258 struct timespec64 boot;
1259
1260 /* steal creds */
1261 rsci.cred = ud->creds;
1262 memset(&ud->creds, 0, sizeof(struct svc_cred));
1263
1264 status = -EOPNOTSUPP;
1265 /* get mech handle from OID */
1266 gm = gss_mech_get_by_OID(&ud->mech_oid);
1267 if (!gm)
1268 goto out;
1269 rsci.cred.cr_gss_mech = gm;
1270
1271 status = -EINVAL;
1272 /* mech-specific data: */
1273 status = gss_import_sec_context(ud->out_handle.data,
1274 ud->out_handle.len,
1275 gm, &rsci.mechctx,
1276 &expiry, GFP_KERNEL);
1277 if (status)
1278 goto out;
1279
1280 getboottime64(&boot);
1281 expiry -= boot.tv_sec;
1282 }
1283
1284 rsci.h.expiry_time = expiry;
1285 rscp = rsc_update(cd, &rsci, rscp);
1286 status = 0;
1287out:
1288 rsc_free(&rsci);
1289 if (rscp)
1290 cache_put(&rscp->h, cd);
1291 else
1292 status = -ENOMEM;
1293 return status;
1294}
1295
1296static int svcauth_gss_proxy_init(struct svc_rqst *rqstp,
1297 struct rpc_gss_wire_cred *gc)
1298{
1299 struct xdr_netobj cli_handle;
1300 struct gssp_upcall_data ud;
1301 uint64_t handle;
1302 int status;
1303 int ret;
1304 struct net *net = SVC_NET(rqstp);
1305 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1306
1307 memset(&ud, 0, sizeof(ud));
1308 ret = gss_read_proxy_verf(rqstp, gc, &ud.in_handle, &ud.in_token);
1309 if (ret)
1310 return ret;
1311
1312 ret = SVC_CLOSE;
1313
1314 /* Perform synchronous upcall to gss-proxy */
1315 status = gssp_accept_sec_context_upcall(net, &ud);
1316 if (status)
1317 goto out;
1318
1319 trace_rpcgss_svc_accept_upcall(rqstp, ud.major_status, ud.minor_status);
1320
1321 switch (ud.major_status) {
1322 case GSS_S_CONTINUE_NEEDED:
1323 cli_handle = ud.out_handle;
1324 break;
1325 case GSS_S_COMPLETE:
1326 status = gss_proxy_save_rsc(sn->rsc_cache, &ud, &handle);
1327 if (status)
1328 goto out;
1329 cli_handle.data = (u8 *)&handle;
1330 cli_handle.len = sizeof(handle);
1331 break;
1332 default:
1333 goto out;
1334 }
1335
1336 if (!svcauth_gss_proc_init_verf(sn->rsc_cache, rqstp, &cli_handle,
1337 &ud.major_status, GSS_SEQ_WIN))
1338 goto out;
1339 if (!svcxdr_set_accept_stat(rqstp))
1340 goto out;
1341 if (!svcxdr_encode_gss_init_res(&rqstp->rq_res_stream, &cli_handle,
1342 &ud.out_token, ud.major_status,
1343 ud.minor_status, GSS_SEQ_WIN))
1344 goto out;
1345
1346 ret = SVC_COMPLETE;
1347out:
1348 gss_free_in_token_pages(&ud.in_token);
1349 gssp_free_upcall_data(&ud);
1350 return ret;
1351}
1352
1353/*
1354 * Try to set the sn->use_gss_proxy variable to a new value. We only allow
1355 * it to be changed if it's currently undefined (-1). If it's any other value
1356 * then return -EBUSY unless the type wouldn't have changed anyway.
1357 */
1358static int set_gss_proxy(struct net *net, int type)
1359{
1360 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1361 int ret;
1362
1363 WARN_ON_ONCE(type != 0 && type != 1);
1364 ret = cmpxchg(&sn->use_gss_proxy, -1, type);
1365 if (ret != -1 && ret != type)
1366 return -EBUSY;
1367 return 0;
1368}
1369
1370static bool use_gss_proxy(struct net *net)
1371{
1372 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1373
1374 /* If use_gss_proxy is still undefined, then try to disable it */
1375 if (sn->use_gss_proxy == -1)
1376 set_gss_proxy(net, 0);
1377 return sn->use_gss_proxy;
1378}
1379
1380static noinline_for_stack int
1381svcauth_gss_proc_init(struct svc_rqst *rqstp, struct rpc_gss_wire_cred *gc)
1382{
1383 struct xdr_stream *xdr = &rqstp->rq_arg_stream;
1384 u32 flavor, len;
1385 void *body;
1386
1387 /* Call's verf field: */
1388 if (xdr_stream_decode_opaque_auth(xdr, &flavor, &body, &len) < 0)
1389 return SVC_GARBAGE;
1390 if (flavor != RPC_AUTH_NULL || len != 0) {
1391 rqstp->rq_auth_stat = rpc_autherr_badverf;
1392 return SVC_DENIED;
1393 }
1394
1395 if (gc->gc_proc == RPC_GSS_PROC_INIT && gc->gc_ctx.len != 0) {
1396 rqstp->rq_auth_stat = rpc_autherr_badcred;
1397 return SVC_DENIED;
1398 }
1399
1400 if (!use_gss_proxy(SVC_NET(rqstp)))
1401 return svcauth_gss_legacy_init(rqstp, gc);
1402 return svcauth_gss_proxy_init(rqstp, gc);
1403}
1404
1405#ifdef CONFIG_PROC_FS
1406
1407static ssize_t write_gssp(struct file *file, const char __user *buf,
1408 size_t count, loff_t *ppos)
1409{
1410 struct net *net = pde_data(file_inode(file));
1411 char tbuf[20];
1412 unsigned long i;
1413 int res;
1414
1415 if (*ppos || count > sizeof(tbuf)-1)
1416 return -EINVAL;
1417 if (copy_from_user(tbuf, buf, count))
1418 return -EFAULT;
1419
1420 tbuf[count] = 0;
1421 res = kstrtoul(tbuf, 0, &i);
1422 if (res)
1423 return res;
1424 if (i != 1)
1425 return -EINVAL;
1426 res = set_gssp_clnt(net);
1427 if (res)
1428 return res;
1429 res = set_gss_proxy(net, 1);
1430 if (res)
1431 return res;
1432 return count;
1433}
1434
1435static ssize_t read_gssp(struct file *file, char __user *buf,
1436 size_t count, loff_t *ppos)
1437{
1438 struct net *net = pde_data(file_inode(file));
1439 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1440 unsigned long p = *ppos;
1441 char tbuf[10];
1442 size_t len;
1443
1444 snprintf(tbuf, sizeof(tbuf), "%d\n", sn->use_gss_proxy);
1445 len = strlen(tbuf);
1446 if (p >= len)
1447 return 0;
1448 len -= p;
1449 if (len > count)
1450 len = count;
1451 if (copy_to_user(buf, (void *)(tbuf+p), len))
1452 return -EFAULT;
1453 *ppos += len;
1454 return len;
1455}
1456
1457static const struct proc_ops use_gss_proxy_proc_ops = {
1458 .proc_open = nonseekable_open,
1459 .proc_write = write_gssp,
1460 .proc_read = read_gssp,
1461};
1462
1463static int create_use_gss_proxy_proc_entry(struct net *net)
1464{
1465 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1466 struct proc_dir_entry **p = &sn->use_gssp_proc;
1467
1468 sn->use_gss_proxy = -1;
1469 *p = proc_create_data("use-gss-proxy", S_IFREG | 0600,
1470 sn->proc_net_rpc,
1471 &use_gss_proxy_proc_ops, net);
1472 if (!*p)
1473 return -ENOMEM;
1474 init_gssp_clnt(sn);
1475 return 0;
1476}
1477
1478static void destroy_use_gss_proxy_proc_entry(struct net *net)
1479{
1480 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1481
1482 if (sn->use_gssp_proc) {
1483 remove_proc_entry("use-gss-proxy", sn->proc_net_rpc);
1484 clear_gssp_clnt(sn);
1485 }
1486}
1487
1488static ssize_t read_gss_krb5_enctypes(struct file *file, char __user *buf,
1489 size_t count, loff_t *ppos)
1490{
1491 struct rpcsec_gss_oid oid = {
1492 .len = 9,
1493 .data = "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02",
1494 };
1495 struct gss_api_mech *mech;
1496 ssize_t ret;
1497
1498 mech = gss_mech_get_by_OID(&oid);
1499 if (!mech)
1500 return 0;
1501 if (!mech->gm_upcall_enctypes) {
1502 gss_mech_put(mech);
1503 return 0;
1504 }
1505
1506 ret = simple_read_from_buffer(buf, count, ppos,
1507 mech->gm_upcall_enctypes,
1508 strlen(mech->gm_upcall_enctypes));
1509 gss_mech_put(mech);
1510 return ret;
1511}
1512
1513static const struct proc_ops gss_krb5_enctypes_proc_ops = {
1514 .proc_open = nonseekable_open,
1515 .proc_read = read_gss_krb5_enctypes,
1516};
1517
1518static int create_krb5_enctypes_proc_entry(struct net *net)
1519{
1520 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1521
1522 sn->gss_krb5_enctypes =
1523 proc_create_data("gss_krb5_enctypes", S_IFREG | 0444,
1524 sn->proc_net_rpc, &gss_krb5_enctypes_proc_ops,
1525 net);
1526 return sn->gss_krb5_enctypes ? 0 : -ENOMEM;
1527}
1528
1529static void destroy_krb5_enctypes_proc_entry(struct net *net)
1530{
1531 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1532
1533 if (sn->gss_krb5_enctypes)
1534 remove_proc_entry("gss_krb5_enctypes", sn->proc_net_rpc);
1535}
1536
1537#else /* CONFIG_PROC_FS */
1538
1539static int create_use_gss_proxy_proc_entry(struct net *net)
1540{
1541 return 0;
1542}
1543
1544static void destroy_use_gss_proxy_proc_entry(struct net *net) {}
1545
1546static int create_krb5_enctypes_proc_entry(struct net *net)
1547{
1548 return 0;
1549}
1550
1551static void destroy_krb5_enctypes_proc_entry(struct net *net) {}
1552
1553#endif /* CONFIG_PROC_FS */
1554
1555/*
1556 * The Call's credential body should contain a struct rpc_gss_cred_t.
1557 *
1558 * RFC 2203 Section 5
1559 *
1560 * struct rpc_gss_cred_t {
1561 * union switch (unsigned int version) {
1562 * case RPCSEC_GSS_VERS_1:
1563 * struct {
1564 * rpc_gss_proc_t gss_proc;
1565 * unsigned int seq_num;
1566 * rpc_gss_service_t service;
1567 * opaque handle<>;
1568 * } rpc_gss_cred_vers_1_t;
1569 * }
1570 * };
1571 */
1572static bool
1573svcauth_gss_decode_credbody(struct xdr_stream *xdr,
1574 struct rpc_gss_wire_cred *gc,
1575 __be32 **rpcstart)
1576{
1577 ssize_t handle_len;
1578 u32 body_len;
1579 __be32 *p;
1580
1581 p = xdr_inline_decode(xdr, XDR_UNIT);
1582 if (!p)
1583 return false;
1584 /*
1585 * start of rpc packet is 7 u32's back from here:
1586 * xid direction rpcversion prog vers proc flavour
1587 */
1588 *rpcstart = p - 7;
1589 body_len = be32_to_cpup(p);
1590 if (body_len > RPC_MAX_AUTH_SIZE)
1591 return false;
1592
1593 /* struct rpc_gss_cred_t */
1594 if (xdr_stream_decode_u32(xdr, &gc->gc_v) < 0)
1595 return false;
1596 if (xdr_stream_decode_u32(xdr, &gc->gc_proc) < 0)
1597 return false;
1598 if (xdr_stream_decode_u32(xdr, &gc->gc_seq) < 0)
1599 return false;
1600 if (xdr_stream_decode_u32(xdr, &gc->gc_svc) < 0)
1601 return false;
1602 handle_len = xdr_stream_decode_opaque_inline(xdr,
1603 (void **)&gc->gc_ctx.data,
1604 body_len);
1605 if (handle_len < 0)
1606 return false;
1607 if (body_len != XDR_UNIT * 5 + xdr_align_size(handle_len))
1608 return false;
1609
1610 gc->gc_ctx.len = handle_len;
1611 return true;
1612}
1613
1614/**
1615 * svcauth_gss_accept - Decode and validate incoming RPC_AUTH_GSS credential
1616 * @rqstp: RPC transaction
1617 *
1618 * Return values:
1619 * %SVC_OK: Success
1620 * %SVC_COMPLETE: GSS context lifetime event
1621 * %SVC_DENIED: Credential or verifier is not valid
1622 * %SVC_GARBAGE: Failed to decode credential or verifier
1623 * %SVC_CLOSE: Temporary failure
1624 *
1625 * The rqstp->rq_auth_stat field is also set (see RFCs 2203 and 5531).
1626 */
1627static enum svc_auth_status
1628svcauth_gss_accept(struct svc_rqst *rqstp)
1629{
1630 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
1631 __be32 *rpcstart;
1632 struct rpc_gss_wire_cred *gc;
1633 struct rsc *rsci = NULL;
1634 int ret;
1635 struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id);
1636
1637 rqstp->rq_auth_stat = rpc_autherr_badcred;
1638 if (!svcdata)
1639 svcdata = kmalloc(sizeof(*svcdata), GFP_KERNEL);
1640 if (!svcdata)
1641 goto auth_err;
1642 rqstp->rq_auth_data = svcdata;
1643 svcdata->gsd_databody_offset = 0;
1644 svcdata->rsci = NULL;
1645 gc = &svcdata->clcred;
1646
1647 if (!svcauth_gss_decode_credbody(&rqstp->rq_arg_stream, gc, &rpcstart))
1648 goto auth_err;
1649 if (gc->gc_v != RPC_GSS_VERSION)
1650 goto auth_err;
1651
1652 switch (gc->gc_proc) {
1653 case RPC_GSS_PROC_INIT:
1654 case RPC_GSS_PROC_CONTINUE_INIT:
1655 if (rqstp->rq_proc != 0)
1656 goto auth_err;
1657 return svcauth_gss_proc_init(rqstp, gc);
1658 case RPC_GSS_PROC_DESTROY:
1659 if (rqstp->rq_proc != 0)
1660 goto auth_err;
1661 fallthrough;
1662 case RPC_GSS_PROC_DATA:
1663 rqstp->rq_auth_stat = rpcsec_gsserr_credproblem;
1664 rsci = gss_svc_searchbyctx(sn->rsc_cache, &gc->gc_ctx);
1665 if (!rsci)
1666 goto auth_err;
1667 switch (svcauth_gss_verify_header(rqstp, rsci, rpcstart, gc)) {
1668 case SVC_OK:
1669 break;
1670 case SVC_DENIED:
1671 goto auth_err;
1672 case SVC_DROP:
1673 goto drop;
1674 }
1675 break;
1676 default:
1677 if (rqstp->rq_proc != 0)
1678 goto auth_err;
1679 rqstp->rq_auth_stat = rpc_autherr_rejectedcred;
1680 goto auth_err;
1681 }
1682
1683 /* now act upon the command: */
1684 switch (gc->gc_proc) {
1685 case RPC_GSS_PROC_DESTROY:
1686 if (!svcauth_gss_encode_verf(rqstp, rsci->mechctx, gc->gc_seq))
1687 goto auth_err;
1688 if (!svcxdr_set_accept_stat(rqstp))
1689 goto auth_err;
1690 /* Delete the entry from the cache_list and call cache_put */
1691 sunrpc_cache_unhash(sn->rsc_cache, &rsci->h);
1692 goto complete;
1693 case RPC_GSS_PROC_DATA:
1694 rqstp->rq_auth_stat = rpcsec_gsserr_ctxproblem;
1695 if (!svcauth_gss_encode_verf(rqstp, rsci->mechctx, gc->gc_seq))
1696 goto auth_err;
1697 if (!svcxdr_set_accept_stat(rqstp))
1698 goto auth_err;
1699 svcdata->gsd_databody_offset = xdr_stream_pos(&rqstp->rq_res_stream);
1700 rqstp->rq_cred = rsci->cred;
1701 get_group_info(rsci->cred.cr_group_info);
1702 rqstp->rq_auth_stat = rpc_autherr_badcred;
1703 switch (gc->gc_svc) {
1704 case RPC_GSS_SVC_NONE:
1705 break;
1706 case RPC_GSS_SVC_INTEGRITY:
1707 /* placeholders for body length and seq. number: */
1708 xdr_reserve_space(&rqstp->rq_res_stream, XDR_UNIT * 2);
1709 if (svcauth_gss_unwrap_integ(rqstp, gc->gc_seq,
1710 rsci->mechctx))
1711 goto garbage_args;
1712 svcxdr_set_auth_slack(rqstp, RPC_MAX_AUTH_SIZE);
1713 break;
1714 case RPC_GSS_SVC_PRIVACY:
1715 /* placeholders for body length and seq. number: */
1716 xdr_reserve_space(&rqstp->rq_res_stream, XDR_UNIT * 2);
1717 if (svcauth_gss_unwrap_priv(rqstp, gc->gc_seq,
1718 rsci->mechctx))
1719 goto garbage_args;
1720 svcxdr_set_auth_slack(rqstp, RPC_MAX_AUTH_SIZE * 2);
1721 break;
1722 default:
1723 goto auth_err;
1724 }
1725 svcdata->rsci = rsci;
1726 cache_get(&rsci->h);
1727 rqstp->rq_cred.cr_flavor = gss_svc_to_pseudoflavor(
1728 rsci->mechctx->mech_type,
1729 GSS_C_QOP_DEFAULT,
1730 gc->gc_svc);
1731 ret = SVC_OK;
1732 trace_rpcgss_svc_authenticate(rqstp, gc);
1733 goto out;
1734 }
1735garbage_args:
1736 ret = SVC_GARBAGE;
1737 goto out;
1738auth_err:
1739 xdr_truncate_encode(&rqstp->rq_res_stream, XDR_UNIT * 2);
1740 ret = SVC_DENIED;
1741 goto out;
1742complete:
1743 ret = SVC_COMPLETE;
1744 goto out;
1745drop:
1746 ret = SVC_CLOSE;
1747out:
1748 if (rsci)
1749 cache_put(&rsci->h, sn->rsc_cache);
1750 return ret;
1751}
1752
1753static u32
1754svcauth_gss_prepare_to_wrap(struct svc_rqst *rqstp, struct gss_svc_data *gsd)
1755{
1756 u32 offset;
1757
1758 /* Release can be called twice, but we only wrap once. */
1759 offset = gsd->gsd_databody_offset;
1760 gsd->gsd_databody_offset = 0;
1761
1762 /* AUTH_ERROR replies are not wrapped. */
1763 if (rqstp->rq_auth_stat != rpc_auth_ok)
1764 return 0;
1765
1766 /* Also don't wrap if the accept_stat is nonzero: */
1767 if (*rqstp->rq_accept_statp != rpc_success)
1768 return 0;
1769
1770 return offset;
1771}
1772
1773/*
1774 * RFC 2203, Section 5.3.2.2
1775 *
1776 * struct rpc_gss_integ_data {
1777 * opaque databody_integ<>;
1778 * opaque checksum<>;
1779 * };
1780 *
1781 * struct rpc_gss_data_t {
1782 * unsigned int seq_num;
1783 * proc_req_arg_t arg;
1784 * };
1785 *
1786 * The RPC Reply message has already been XDR-encoded. rq_res_stream
1787 * is now positioned so that the checksum can be written just past
1788 * the RPC Reply message.
1789 */
1790static int svcauth_gss_wrap_integ(struct svc_rqst *rqstp)
1791{
1792 struct gss_svc_data *gsd = rqstp->rq_auth_data;
1793 struct xdr_stream *xdr = &rqstp->rq_res_stream;
1794 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1795 struct xdr_buf *buf = xdr->buf;
1796 struct xdr_buf databody_integ;
1797 struct xdr_netobj checksum;
1798 u32 offset, maj_stat;
1799
1800 offset = svcauth_gss_prepare_to_wrap(rqstp, gsd);
1801 if (!offset)
1802 goto out;
1803
1804 if (xdr_buf_subsegment(buf, &databody_integ, offset + XDR_UNIT,
1805 buf->len - offset - XDR_UNIT))
1806 goto wrap_failed;
1807 /* Buffer space for these has already been reserved in
1808 * svcauth_gss_accept(). */
1809 if (xdr_encode_word(buf, offset, databody_integ.len))
1810 goto wrap_failed;
1811 if (xdr_encode_word(buf, offset + XDR_UNIT, gc->gc_seq))
1812 goto wrap_failed;
1813
1814 checksum.data = gsd->gsd_scratch;
1815 maj_stat = gss_get_mic(gsd->rsci->mechctx, &databody_integ, &checksum);
1816 if (maj_stat != GSS_S_COMPLETE)
1817 goto bad_mic;
1818
1819 if (xdr_stream_encode_opaque(xdr, checksum.data, checksum.len) < 0)
1820 goto wrap_failed;
1821 xdr_commit_encode(xdr);
1822
1823out:
1824 return 0;
1825
1826bad_mic:
1827 trace_rpcgss_svc_get_mic(rqstp, maj_stat);
1828 return -EINVAL;
1829wrap_failed:
1830 trace_rpcgss_svc_wrap_failed(rqstp);
1831 return -EINVAL;
1832}
1833
1834/*
1835 * RFC 2203, Section 5.3.2.3
1836 *
1837 * struct rpc_gss_priv_data {
1838 * opaque databody_priv<>
1839 * };
1840 *
1841 * struct rpc_gss_data_t {
1842 * unsigned int seq_num;
1843 * proc_req_arg_t arg;
1844 * };
1845 *
1846 * gss_wrap() expands the size of the RPC message payload in the
1847 * response buffer. The main purpose of svcauth_gss_wrap_priv()
1848 * is to ensure there is adequate space in the response buffer to
1849 * avoid overflow during the wrap.
1850 */
1851static int svcauth_gss_wrap_priv(struct svc_rqst *rqstp)
1852{
1853 struct gss_svc_data *gsd = rqstp->rq_auth_data;
1854 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1855 struct xdr_buf *buf = &rqstp->rq_res;
1856 struct kvec *head = buf->head;
1857 struct kvec *tail = buf->tail;
1858 u32 offset, pad, maj_stat;
1859 __be32 *p;
1860
1861 offset = svcauth_gss_prepare_to_wrap(rqstp, gsd);
1862 if (!offset)
1863 return 0;
1864
1865 /*
1866 * Buffer space for this field has already been reserved
1867 * in svcauth_gss_accept(). Note that the GSS sequence
1868 * number is encrypted along with the RPC reply payload.
1869 */
1870 if (xdr_encode_word(buf, offset + XDR_UNIT, gc->gc_seq))
1871 goto wrap_failed;
1872
1873 /*
1874 * If there is currently tail data, make sure there is
1875 * room for the head, tail, and 2 * RPC_MAX_AUTH_SIZE in
1876 * the page, and move the current tail data such that
1877 * there is RPC_MAX_AUTH_SIZE slack space available in
1878 * both the head and tail.
1879 */
1880 if (tail->iov_base) {
1881 if (tail->iov_base >= head->iov_base + PAGE_SIZE)
1882 goto wrap_failed;
1883 if (tail->iov_base < head->iov_base)
1884 goto wrap_failed;
1885 if (tail->iov_len + head->iov_len
1886 + 2 * RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1887 goto wrap_failed;
1888 memmove(tail->iov_base + RPC_MAX_AUTH_SIZE, tail->iov_base,
1889 tail->iov_len);
1890 tail->iov_base += RPC_MAX_AUTH_SIZE;
1891 }
1892 /*
1893 * If there is no current tail data, make sure there is
1894 * room for the head data, and 2 * RPC_MAX_AUTH_SIZE in the
1895 * allotted page, and set up tail information such that there
1896 * is RPC_MAX_AUTH_SIZE slack space available in both the
1897 * head and tail.
1898 */
1899 if (!tail->iov_base) {
1900 if (head->iov_len + 2 * RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1901 goto wrap_failed;
1902 tail->iov_base = head->iov_base
1903 + head->iov_len + RPC_MAX_AUTH_SIZE;
1904 tail->iov_len = 0;
1905 }
1906
1907 maj_stat = gss_wrap(gsd->rsci->mechctx, offset + XDR_UNIT, buf,
1908 buf->pages);
1909 if (maj_stat != GSS_S_COMPLETE)
1910 goto bad_wrap;
1911
1912 /* Wrapping can change the size of databody_priv. */
1913 if (xdr_encode_word(buf, offset, buf->len - offset - XDR_UNIT))
1914 goto wrap_failed;
1915 pad = xdr_pad_size(buf->len - offset - XDR_UNIT);
1916 p = (__be32 *)(tail->iov_base + tail->iov_len);
1917 memset(p, 0, pad);
1918 tail->iov_len += pad;
1919 buf->len += pad;
1920
1921 return 0;
1922wrap_failed:
1923 trace_rpcgss_svc_wrap_failed(rqstp);
1924 return -EINVAL;
1925bad_wrap:
1926 trace_rpcgss_svc_wrap(rqstp, maj_stat);
1927 return -ENOMEM;
1928}
1929
1930/**
1931 * svcauth_gss_release - Wrap payload and release resources
1932 * @rqstp: RPC transaction context
1933 *
1934 * Return values:
1935 * %0: the Reply is ready to be sent
1936 * %-ENOMEM: failed to allocate memory
1937 * %-EINVAL: encoding error
1938 */
1939static int
1940svcauth_gss_release(struct svc_rqst *rqstp)
1941{
1942 struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id);
1943 struct gss_svc_data *gsd = rqstp->rq_auth_data;
1944 struct rpc_gss_wire_cred *gc;
1945 int stat;
1946
1947 if (!gsd)
1948 goto out;
1949 gc = &gsd->clcred;
1950 if (gc->gc_proc != RPC_GSS_PROC_DATA)
1951 goto out;
1952
1953 switch (gc->gc_svc) {
1954 case RPC_GSS_SVC_NONE:
1955 break;
1956 case RPC_GSS_SVC_INTEGRITY:
1957 stat = svcauth_gss_wrap_integ(rqstp);
1958 if (stat)
1959 goto out_err;
1960 break;
1961 case RPC_GSS_SVC_PRIVACY:
1962 stat = svcauth_gss_wrap_priv(rqstp);
1963 if (stat)
1964 goto out_err;
1965 break;
1966 /*
1967 * For any other gc_svc value, svcauth_gss_accept() already set
1968 * the auth_error appropriately; just fall through:
1969 */
1970 }
1971
1972out:
1973 stat = 0;
1974out_err:
1975 if (rqstp->rq_client)
1976 auth_domain_put(rqstp->rq_client);
1977 rqstp->rq_client = NULL;
1978 if (rqstp->rq_gssclient)
1979 auth_domain_put(rqstp->rq_gssclient);
1980 rqstp->rq_gssclient = NULL;
1981 if (rqstp->rq_cred.cr_group_info)
1982 put_group_info(rqstp->rq_cred.cr_group_info);
1983 rqstp->rq_cred.cr_group_info = NULL;
1984 if (gsd && gsd->rsci) {
1985 cache_put(&gsd->rsci->h, sn->rsc_cache);
1986 gsd->rsci = NULL;
1987 }
1988 return stat;
1989}
1990
1991static void
1992svcauth_gss_domain_release_rcu(struct rcu_head *head)
1993{
1994 struct auth_domain *dom = container_of(head, struct auth_domain, rcu_head);
1995 struct gss_domain *gd = container_of(dom, struct gss_domain, h);
1996
1997 kfree(dom->name);
1998 kfree(gd);
1999}
2000
2001static void
2002svcauth_gss_domain_release(struct auth_domain *dom)
2003{
2004 call_rcu(&dom->rcu_head, svcauth_gss_domain_release_rcu);
2005}
2006
2007static rpc_authflavor_t svcauth_gss_pseudoflavor(struct svc_rqst *rqstp)
2008{
2009 return svcauth_gss_flavor(rqstp->rq_gssclient);
2010}
2011
2012static struct auth_ops svcauthops_gss = {
2013 .name = "rpcsec_gss",
2014 .owner = THIS_MODULE,
2015 .flavour = RPC_AUTH_GSS,
2016 .accept = svcauth_gss_accept,
2017 .release = svcauth_gss_release,
2018 .domain_release = svcauth_gss_domain_release,
2019 .set_client = svcauth_gss_set_client,
2020 .pseudoflavor = svcauth_gss_pseudoflavor,
2021};
2022
2023static int rsi_cache_create_net(struct net *net)
2024{
2025 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
2026 struct cache_detail *cd;
2027 int err;
2028
2029 cd = cache_create_net(&rsi_cache_template, net);
2030 if (IS_ERR(cd))
2031 return PTR_ERR(cd);
2032 err = cache_register_net(cd, net);
2033 if (err) {
2034 cache_destroy_net(cd, net);
2035 return err;
2036 }
2037 sn->rsi_cache = cd;
2038 return 0;
2039}
2040
2041static void rsi_cache_destroy_net(struct net *net)
2042{
2043 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
2044 struct cache_detail *cd = sn->rsi_cache;
2045
2046 sn->rsi_cache = NULL;
2047 cache_purge(cd);
2048 cache_unregister_net(cd, net);
2049 cache_destroy_net(cd, net);
2050}
2051
2052static int rsc_cache_create_net(struct net *net)
2053{
2054 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
2055 struct cache_detail *cd;
2056 int err;
2057
2058 cd = cache_create_net(&rsc_cache_template, net);
2059 if (IS_ERR(cd))
2060 return PTR_ERR(cd);
2061 err = cache_register_net(cd, net);
2062 if (err) {
2063 cache_destroy_net(cd, net);
2064 return err;
2065 }
2066 sn->rsc_cache = cd;
2067 return 0;
2068}
2069
2070static void rsc_cache_destroy_net(struct net *net)
2071{
2072 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
2073 struct cache_detail *cd = sn->rsc_cache;
2074
2075 sn->rsc_cache = NULL;
2076 cache_purge(cd);
2077 cache_unregister_net(cd, net);
2078 cache_destroy_net(cd, net);
2079}
2080
2081int
2082gss_svc_init_net(struct net *net)
2083{
2084 int rv;
2085
2086 rv = rsc_cache_create_net(net);
2087 if (rv)
2088 return rv;
2089 rv = rsi_cache_create_net(net);
2090 if (rv)
2091 goto out1;
2092 rv = create_use_gss_proxy_proc_entry(net);
2093 if (rv)
2094 goto out2;
2095
2096 rv = create_krb5_enctypes_proc_entry(net);
2097 if (rv)
2098 goto out3;
2099
2100 return 0;
2101
2102out3:
2103 destroy_use_gss_proxy_proc_entry(net);
2104out2:
2105 rsi_cache_destroy_net(net);
2106out1:
2107 rsc_cache_destroy_net(net);
2108 return rv;
2109}
2110
2111void
2112gss_svc_shutdown_net(struct net *net)
2113{
2114 destroy_krb5_enctypes_proc_entry(net);
2115 destroy_use_gss_proxy_proc_entry(net);
2116 rsi_cache_destroy_net(net);
2117 rsc_cache_destroy_net(net);
2118}
2119
2120int
2121gss_svc_init(void)
2122{
2123 return svc_auth_register(RPC_AUTH_GSS, &svcauthops_gss);
2124}
2125
2126void
2127gss_svc_shutdown(void)
2128{
2129 svc_auth_unregister(RPC_AUTH_GSS);
2130}
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#if IS_ENABLED(CONFIG_SUNRPC_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 const 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 if (N < 0 || N > NGROUPS_MAX)
467 goto out;
468 status = -ENOMEM;
469 rsci.cred.cr_group_info = groups_alloc(N);
470 if (rsci.cred.cr_group_info == NULL)
471 goto out;
472
473 /* gid's */
474 status = -EINVAL;
475 for (i=0; i<N; i++) {
476 kgid_t kgid;
477 if (get_int(&mesg, &id))
478 goto out;
479 kgid = make_kgid(&init_user_ns, id);
480 if (!gid_valid(kgid))
481 goto out;
482 rsci.cred.cr_group_info->gid[i] = kgid;
483 }
484 groups_sort(rsci.cred.cr_group_info);
485
486 /* mech name */
487 len = qword_get(&mesg, buf, mlen);
488 if (len < 0)
489 goto out;
490 gm = rsci.cred.cr_gss_mech = gss_mech_get_by_name(buf);
491 status = -EOPNOTSUPP;
492 if (!gm)
493 goto out;
494
495 status = -EINVAL;
496 /* mech-specific data: */
497 len = qword_get(&mesg, buf, mlen);
498 if (len < 0)
499 goto out;
500 status = gss_import_sec_context(buf, len, gm, &rsci.mechctx,
501 NULL, GFP_KERNEL);
502 if (status)
503 goto out;
504
505 /* get client name */
506 len = qword_get(&mesg, buf, mlen);
507 if (len > 0) {
508 rsci.cred.cr_principal = kstrdup(buf, GFP_KERNEL);
509 if (!rsci.cred.cr_principal) {
510 status = -ENOMEM;
511 goto out;
512 }
513 }
514
515 }
516 rsci.h.expiry_time = expiry;
517 rscp = rsc_update(cd, &rsci, rscp);
518 status = 0;
519out:
520 rsc_free(&rsci);
521 if (rscp)
522 cache_put(&rscp->h, cd);
523 else
524 status = -ENOMEM;
525 return status;
526}
527
528static const struct cache_detail rsc_cache_template = {
529 .owner = THIS_MODULE,
530 .hash_size = RSC_HASHMAX,
531 .name = "auth.rpcsec.context",
532 .cache_put = rsc_put,
533 .cache_parse = rsc_parse,
534 .match = rsc_match,
535 .init = rsc_init,
536 .update = update_rsc,
537 .alloc = rsc_alloc,
538};
539
540static struct rsc *rsc_lookup(struct cache_detail *cd, struct rsc *item)
541{
542 struct cache_head *ch;
543 int hash = rsc_hash(item);
544
545 ch = sunrpc_cache_lookup(cd, &item->h, hash);
546 if (ch)
547 return container_of(ch, struct rsc, h);
548 else
549 return NULL;
550}
551
552static struct rsc *rsc_update(struct cache_detail *cd, struct rsc *new, struct rsc *old)
553{
554 struct cache_head *ch;
555 int hash = rsc_hash(new);
556
557 ch = sunrpc_cache_update(cd, &new->h,
558 &old->h, hash);
559 if (ch)
560 return container_of(ch, struct rsc, h);
561 else
562 return NULL;
563}
564
565
566static struct rsc *
567gss_svc_searchbyctx(struct cache_detail *cd, struct xdr_netobj *handle)
568{
569 struct rsc rsci;
570 struct rsc *found;
571
572 memset(&rsci, 0, sizeof(rsci));
573 if (dup_to_netobj(&rsci.handle, handle->data, handle->len))
574 return NULL;
575 found = rsc_lookup(cd, &rsci);
576 rsc_free(&rsci);
577 if (!found)
578 return NULL;
579 if (cache_check(cd, &found->h, NULL))
580 return NULL;
581 return found;
582}
583
584/* Implements sequence number algorithm as specified in RFC 2203. */
585static int
586gss_check_seq_num(struct rsc *rsci, int seq_num)
587{
588 struct gss_svc_seq_data *sd = &rsci->seqdata;
589
590 spin_lock(&sd->sd_lock);
591 if (seq_num > sd->sd_max) {
592 if (seq_num >= sd->sd_max + GSS_SEQ_WIN) {
593 memset(sd->sd_win,0,sizeof(sd->sd_win));
594 sd->sd_max = seq_num;
595 } else while (sd->sd_max < seq_num) {
596 sd->sd_max++;
597 __clear_bit(sd->sd_max % GSS_SEQ_WIN, sd->sd_win);
598 }
599 __set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win);
600 goto ok;
601 } else if (seq_num <= sd->sd_max - GSS_SEQ_WIN) {
602 goto drop;
603 }
604 /* sd_max - GSS_SEQ_WIN < seq_num <= sd_max */
605 if (__test_and_set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win))
606 goto drop;
607ok:
608 spin_unlock(&sd->sd_lock);
609 return 1;
610drop:
611 spin_unlock(&sd->sd_lock);
612 return 0;
613}
614
615static inline u32 round_up_to_quad(u32 i)
616{
617 return (i + 3 ) & ~3;
618}
619
620static inline int
621svc_safe_getnetobj(struct kvec *argv, struct xdr_netobj *o)
622{
623 int l;
624
625 if (argv->iov_len < 4)
626 return -1;
627 o->len = svc_getnl(argv);
628 l = round_up_to_quad(o->len);
629 if (argv->iov_len < l)
630 return -1;
631 o->data = argv->iov_base;
632 argv->iov_base += l;
633 argv->iov_len -= l;
634 return 0;
635}
636
637static inline int
638svc_safe_putnetobj(struct kvec *resv, struct xdr_netobj *o)
639{
640 u8 *p;
641
642 if (resv->iov_len + 4 > PAGE_SIZE)
643 return -1;
644 svc_putnl(resv, o->len);
645 p = resv->iov_base + resv->iov_len;
646 resv->iov_len += round_up_to_quad(o->len);
647 if (resv->iov_len > PAGE_SIZE)
648 return -1;
649 memcpy(p, o->data, o->len);
650 memset(p + o->len, 0, round_up_to_quad(o->len) - o->len);
651 return 0;
652}
653
654/*
655 * Verify the checksum on the header and return SVC_OK on success.
656 * Otherwise, return SVC_DROP (in the case of a bad sequence number)
657 * or return SVC_DENIED and indicate error in authp.
658 */
659static int
660gss_verify_header(struct svc_rqst *rqstp, struct rsc *rsci,
661 __be32 *rpcstart, struct rpc_gss_wire_cred *gc, __be32 *authp)
662{
663 struct gss_ctx *ctx_id = rsci->mechctx;
664 struct xdr_buf rpchdr;
665 struct xdr_netobj checksum;
666 u32 flavor = 0;
667 struct kvec *argv = &rqstp->rq_arg.head[0];
668 struct kvec iov;
669
670 /* data to compute the checksum over: */
671 iov.iov_base = rpcstart;
672 iov.iov_len = (u8 *)argv->iov_base - (u8 *)rpcstart;
673 xdr_buf_from_iov(&iov, &rpchdr);
674
675 *authp = rpc_autherr_badverf;
676 if (argv->iov_len < 4)
677 return SVC_DENIED;
678 flavor = svc_getnl(argv);
679 if (flavor != RPC_AUTH_GSS)
680 return SVC_DENIED;
681 if (svc_safe_getnetobj(argv, &checksum))
682 return SVC_DENIED;
683
684 if (rqstp->rq_deferred) /* skip verification of revisited request */
685 return SVC_OK;
686 if (gss_verify_mic(ctx_id, &rpchdr, &checksum) != GSS_S_COMPLETE) {
687 *authp = rpcsec_gsserr_credproblem;
688 return SVC_DENIED;
689 }
690
691 if (gc->gc_seq > MAXSEQ) {
692 dprintk("RPC: svcauth_gss: discarding request with "
693 "large sequence number %d\n", gc->gc_seq);
694 *authp = rpcsec_gsserr_ctxproblem;
695 return SVC_DENIED;
696 }
697 if (!gss_check_seq_num(rsci, gc->gc_seq)) {
698 dprintk("RPC: svcauth_gss: discarding request with "
699 "old sequence number %d\n", gc->gc_seq);
700 return SVC_DROP;
701 }
702 return SVC_OK;
703}
704
705static int
706gss_write_null_verf(struct svc_rqst *rqstp)
707{
708 __be32 *p;
709
710 svc_putnl(rqstp->rq_res.head, RPC_AUTH_NULL);
711 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len;
712 /* don't really need to check if head->iov_len > PAGE_SIZE ... */
713 *p++ = 0;
714 if (!xdr_ressize_check(rqstp, p))
715 return -1;
716 return 0;
717}
718
719static int
720gss_write_verf(struct svc_rqst *rqstp, struct gss_ctx *ctx_id, u32 seq)
721{
722 __be32 *xdr_seq;
723 u32 maj_stat;
724 struct xdr_buf verf_data;
725 struct xdr_netobj mic;
726 __be32 *p;
727 struct kvec iov;
728 int err = -1;
729
730 svc_putnl(rqstp->rq_res.head, RPC_AUTH_GSS);
731 xdr_seq = kmalloc(4, GFP_KERNEL);
732 if (!xdr_seq)
733 return -1;
734 *xdr_seq = htonl(seq);
735
736 iov.iov_base = xdr_seq;
737 iov.iov_len = 4;
738 xdr_buf_from_iov(&iov, &verf_data);
739 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len;
740 mic.data = (u8 *)(p + 1);
741 maj_stat = gss_get_mic(ctx_id, &verf_data, &mic);
742 if (maj_stat != GSS_S_COMPLETE)
743 goto out;
744 *p++ = htonl(mic.len);
745 memset((u8 *)p + mic.len, 0, round_up_to_quad(mic.len) - mic.len);
746 p += XDR_QUADLEN(mic.len);
747 if (!xdr_ressize_check(rqstp, p))
748 goto out;
749 err = 0;
750out:
751 kfree(xdr_seq);
752 return err;
753}
754
755struct gss_domain {
756 struct auth_domain h;
757 u32 pseudoflavor;
758};
759
760static struct auth_domain *
761find_gss_auth_domain(struct gss_ctx *ctx, u32 svc)
762{
763 char *name;
764
765 name = gss_service_to_auth_domain_name(ctx->mech_type, svc);
766 if (!name)
767 return NULL;
768 return auth_domain_find(name);
769}
770
771static struct auth_ops svcauthops_gss;
772
773u32 svcauth_gss_flavor(struct auth_domain *dom)
774{
775 struct gss_domain *gd = container_of(dom, struct gss_domain, h);
776
777 return gd->pseudoflavor;
778}
779
780EXPORT_SYMBOL_GPL(svcauth_gss_flavor);
781
782int
783svcauth_gss_register_pseudoflavor(u32 pseudoflavor, char * name)
784{
785 struct gss_domain *new;
786 struct auth_domain *test;
787 int stat = -ENOMEM;
788
789 new = kmalloc(sizeof(*new), GFP_KERNEL);
790 if (!new)
791 goto out;
792 kref_init(&new->h.ref);
793 new->h.name = kstrdup(name, GFP_KERNEL);
794 if (!new->h.name)
795 goto out_free_dom;
796 new->h.flavour = &svcauthops_gss;
797 new->pseudoflavor = pseudoflavor;
798
799 stat = 0;
800 test = auth_domain_lookup(name, &new->h);
801 if (test != &new->h) { /* Duplicate registration */
802 auth_domain_put(test);
803 kfree(new->h.name);
804 goto out_free_dom;
805 }
806 return 0;
807
808out_free_dom:
809 kfree(new);
810out:
811 return stat;
812}
813
814EXPORT_SYMBOL_GPL(svcauth_gss_register_pseudoflavor);
815
816static inline int
817read_u32_from_xdr_buf(struct xdr_buf *buf, int base, u32 *obj)
818{
819 __be32 raw;
820 int status;
821
822 status = read_bytes_from_xdr_buf(buf, base, &raw, sizeof(*obj));
823 if (status)
824 return status;
825 *obj = ntohl(raw);
826 return 0;
827}
828
829/* It would be nice if this bit of code could be shared with the client.
830 * Obstacles:
831 * The client shouldn't malloc(), would have to pass in own memory.
832 * The server uses base of head iovec as read pointer, while the
833 * client uses separate pointer. */
834static int
835unwrap_integ_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx)
836{
837 int stat = -EINVAL;
838 u32 integ_len, maj_stat;
839 struct xdr_netobj mic;
840 struct xdr_buf integ_buf;
841
842 /* NFS READ normally uses splice to send data in-place. However
843 * the data in cache can change after the reply's MIC is computed
844 * but before the RPC reply is sent. To prevent the client from
845 * rejecting the server-computed MIC in this somewhat rare case,
846 * do not use splice with the GSS integrity service.
847 */
848 clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
849
850 /* Did we already verify the signature on the original pass through? */
851 if (rqstp->rq_deferred)
852 return 0;
853
854 integ_len = svc_getnl(&buf->head[0]);
855 if (integ_len & 3)
856 return stat;
857 if (integ_len > buf->len)
858 return stat;
859 if (xdr_buf_subsegment(buf, &integ_buf, 0, integ_len)) {
860 WARN_ON_ONCE(1);
861 return stat;
862 }
863 /* copy out mic... */
864 if (read_u32_from_xdr_buf(buf, integ_len, &mic.len))
865 return stat;
866 if (mic.len > RPC_MAX_AUTH_SIZE)
867 return stat;
868 mic.data = kmalloc(mic.len, GFP_KERNEL);
869 if (!mic.data)
870 return stat;
871 if (read_bytes_from_xdr_buf(buf, integ_len + 4, mic.data, mic.len))
872 goto out;
873 maj_stat = gss_verify_mic(ctx, &integ_buf, &mic);
874 if (maj_stat != GSS_S_COMPLETE)
875 goto out;
876 if (svc_getnl(&buf->head[0]) != seq)
877 goto out;
878 /* trim off the mic and padding at the end before returning */
879 xdr_buf_trim(buf, round_up_to_quad(mic.len) + 4);
880 stat = 0;
881out:
882 kfree(mic.data);
883 return stat;
884}
885
886static inline int
887total_buf_len(struct xdr_buf *buf)
888{
889 return buf->head[0].iov_len + buf->page_len + buf->tail[0].iov_len;
890}
891
892static void
893fix_priv_head(struct xdr_buf *buf, int pad)
894{
895 if (buf->page_len == 0) {
896 /* We need to adjust head and buf->len in tandem in this
897 * case to make svc_defer() work--it finds the original
898 * buffer start using buf->len - buf->head[0].iov_len. */
899 buf->head[0].iov_len -= pad;
900 }
901}
902
903static int
904unwrap_priv_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx)
905{
906 u32 priv_len, maj_stat;
907 int pad, saved_len, remaining_len, offset;
908
909 clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
910
911 priv_len = svc_getnl(&buf->head[0]);
912 if (rqstp->rq_deferred) {
913 /* Already decrypted last time through! The sequence number
914 * check at out_seq is unnecessary but harmless: */
915 goto out_seq;
916 }
917 /* buf->len is the number of bytes from the original start of the
918 * request to the end, where head[0].iov_len is just the bytes
919 * not yet read from the head, so these two values are different: */
920 remaining_len = total_buf_len(buf);
921 if (priv_len > remaining_len)
922 return -EINVAL;
923 pad = remaining_len - priv_len;
924 buf->len -= pad;
925 fix_priv_head(buf, pad);
926
927 /* Maybe it would be better to give gss_unwrap a length parameter: */
928 saved_len = buf->len;
929 buf->len = priv_len;
930 maj_stat = gss_unwrap(ctx, 0, buf);
931 pad = priv_len - buf->len;
932 buf->len = saved_len;
933 buf->len -= pad;
934 /* The upper layers assume the buffer is aligned on 4-byte boundaries.
935 * In the krb5p case, at least, the data ends up offset, so we need to
936 * move it around. */
937 /* XXX: This is very inefficient. It would be better to either do
938 * this while we encrypt, or maybe in the receive code, if we can peak
939 * ahead and work out the service and mechanism there. */
940 offset = buf->head[0].iov_len % 4;
941 if (offset) {
942 buf->buflen = RPCSVC_MAXPAYLOAD;
943 xdr_shift_buf(buf, offset);
944 fix_priv_head(buf, pad);
945 }
946 if (maj_stat != GSS_S_COMPLETE)
947 return -EINVAL;
948out_seq:
949 if (svc_getnl(&buf->head[0]) != seq)
950 return -EINVAL;
951 return 0;
952}
953
954struct gss_svc_data {
955 /* decoded gss client cred: */
956 struct rpc_gss_wire_cred clcred;
957 /* save a pointer to the beginning of the encoded verifier,
958 * for use in encryption/checksumming in svcauth_gss_release: */
959 __be32 *verf_start;
960 struct rsc *rsci;
961};
962
963static int
964svcauth_gss_set_client(struct svc_rqst *rqstp)
965{
966 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
967 struct rsc *rsci = svcdata->rsci;
968 struct rpc_gss_wire_cred *gc = &svcdata->clcred;
969 int stat;
970
971 /*
972 * A gss export can be specified either by:
973 * export *(sec=krb5,rw)
974 * or by
975 * export gss/krb5(rw)
976 * The latter is deprecated; but for backwards compatibility reasons
977 * the nfsd code will still fall back on trying it if the former
978 * doesn't work; so we try to make both available to nfsd, below.
979 */
980 rqstp->rq_gssclient = find_gss_auth_domain(rsci->mechctx, gc->gc_svc);
981 if (rqstp->rq_gssclient == NULL)
982 return SVC_DENIED;
983 stat = svcauth_unix_set_client(rqstp);
984 if (stat == SVC_DROP || stat == SVC_CLOSE)
985 return stat;
986 return SVC_OK;
987}
988
989static inline int
990gss_write_init_verf(struct cache_detail *cd, struct svc_rqst *rqstp,
991 struct xdr_netobj *out_handle, int *major_status)
992{
993 struct rsc *rsci;
994 int rc;
995
996 if (*major_status != GSS_S_COMPLETE)
997 return gss_write_null_verf(rqstp);
998 rsci = gss_svc_searchbyctx(cd, out_handle);
999 if (rsci == NULL) {
1000 *major_status = GSS_S_NO_CONTEXT;
1001 return gss_write_null_verf(rqstp);
1002 }
1003 rc = gss_write_verf(rqstp, rsci->mechctx, GSS_SEQ_WIN);
1004 cache_put(&rsci->h, cd);
1005 return rc;
1006}
1007
1008static inline int
1009gss_read_common_verf(struct rpc_gss_wire_cred *gc,
1010 struct kvec *argv, __be32 *authp,
1011 struct xdr_netobj *in_handle)
1012{
1013 /* Read the verifier; should be NULL: */
1014 *authp = rpc_autherr_badverf;
1015 if (argv->iov_len < 2 * 4)
1016 return SVC_DENIED;
1017 if (svc_getnl(argv) != RPC_AUTH_NULL)
1018 return SVC_DENIED;
1019 if (svc_getnl(argv) != 0)
1020 return SVC_DENIED;
1021 /* Martial context handle and token for upcall: */
1022 *authp = rpc_autherr_badcred;
1023 if (gc->gc_proc == RPC_GSS_PROC_INIT && gc->gc_ctx.len != 0)
1024 return SVC_DENIED;
1025 if (dup_netobj(in_handle, &gc->gc_ctx))
1026 return SVC_CLOSE;
1027 *authp = rpc_autherr_badverf;
1028
1029 return 0;
1030}
1031
1032static inline int
1033gss_read_verf(struct rpc_gss_wire_cred *gc,
1034 struct kvec *argv, __be32 *authp,
1035 struct xdr_netobj *in_handle,
1036 struct xdr_netobj *in_token)
1037{
1038 struct xdr_netobj tmpobj;
1039 int res;
1040
1041 res = gss_read_common_verf(gc, argv, authp, in_handle);
1042 if (res)
1043 return res;
1044
1045 if (svc_safe_getnetobj(argv, &tmpobj)) {
1046 kfree(in_handle->data);
1047 return SVC_DENIED;
1048 }
1049 if (dup_netobj(in_token, &tmpobj)) {
1050 kfree(in_handle->data);
1051 return SVC_CLOSE;
1052 }
1053
1054 return 0;
1055}
1056
1057/* Ok this is really heavily depending on a set of semantics in
1058 * how rqstp is set up by svc_recv and pages laid down by the
1059 * server when reading a request. We are basically guaranteed that
1060 * the token lays all down linearly across a set of pages, starting
1061 * at iov_base in rq_arg.head[0] which happens to be the first of a
1062 * set of pages stored in rq_pages[].
1063 * rq_arg.head[0].iov_base will provide us the page_base to pass
1064 * to the upcall.
1065 */
1066static inline int
1067gss_read_proxy_verf(struct svc_rqst *rqstp,
1068 struct rpc_gss_wire_cred *gc, __be32 *authp,
1069 struct xdr_netobj *in_handle,
1070 struct gssp_in_token *in_token)
1071{
1072 struct kvec *argv = &rqstp->rq_arg.head[0];
1073 u32 inlen;
1074 int res;
1075
1076 res = gss_read_common_verf(gc, argv, authp, in_handle);
1077 if (res)
1078 return res;
1079
1080 inlen = svc_getnl(argv);
1081 if (inlen > (argv->iov_len + rqstp->rq_arg.page_len))
1082 return SVC_DENIED;
1083
1084 in_token->pages = rqstp->rq_pages;
1085 in_token->page_base = (ulong)argv->iov_base & ~PAGE_MASK;
1086 in_token->page_len = inlen;
1087
1088 return 0;
1089}
1090
1091static inline int
1092gss_write_resv(struct kvec *resv, size_t size_limit,
1093 struct xdr_netobj *out_handle, struct xdr_netobj *out_token,
1094 int major_status, int minor_status)
1095{
1096 if (resv->iov_len + 4 > size_limit)
1097 return -1;
1098 svc_putnl(resv, RPC_SUCCESS);
1099 if (svc_safe_putnetobj(resv, out_handle))
1100 return -1;
1101 if (resv->iov_len + 3 * 4 > size_limit)
1102 return -1;
1103 svc_putnl(resv, major_status);
1104 svc_putnl(resv, minor_status);
1105 svc_putnl(resv, GSS_SEQ_WIN);
1106 if (svc_safe_putnetobj(resv, out_token))
1107 return -1;
1108 return 0;
1109}
1110
1111/*
1112 * Having read the cred already and found we're in the context
1113 * initiation case, read the verifier and initiate (or check the results
1114 * of) upcalls to userspace for help with context initiation. If
1115 * the upcall results are available, write the verifier and result.
1116 * Otherwise, drop the request pending an answer to the upcall.
1117 */
1118static int svcauth_gss_legacy_init(struct svc_rqst *rqstp,
1119 struct rpc_gss_wire_cred *gc, __be32 *authp)
1120{
1121 struct kvec *argv = &rqstp->rq_arg.head[0];
1122 struct kvec *resv = &rqstp->rq_res.head[0];
1123 struct rsi *rsip, rsikey;
1124 int ret;
1125 struct sunrpc_net *sn = net_generic(rqstp->rq_xprt->xpt_net, sunrpc_net_id);
1126
1127 memset(&rsikey, 0, sizeof(rsikey));
1128 ret = gss_read_verf(gc, argv, authp,
1129 &rsikey.in_handle, &rsikey.in_token);
1130 if (ret)
1131 return ret;
1132
1133 /* Perform upcall, or find upcall result: */
1134 rsip = rsi_lookup(sn->rsi_cache, &rsikey);
1135 rsi_free(&rsikey);
1136 if (!rsip)
1137 return SVC_CLOSE;
1138 if (cache_check(sn->rsi_cache, &rsip->h, &rqstp->rq_chandle) < 0)
1139 /* No upcall result: */
1140 return SVC_CLOSE;
1141
1142 ret = SVC_CLOSE;
1143 /* Got an answer to the upcall; use it: */
1144 if (gss_write_init_verf(sn->rsc_cache, rqstp,
1145 &rsip->out_handle, &rsip->major_status))
1146 goto out;
1147 if (gss_write_resv(resv, PAGE_SIZE,
1148 &rsip->out_handle, &rsip->out_token,
1149 rsip->major_status, rsip->minor_status))
1150 goto out;
1151
1152 ret = SVC_COMPLETE;
1153out:
1154 cache_put(&rsip->h, sn->rsi_cache);
1155 return ret;
1156}
1157
1158static int gss_proxy_save_rsc(struct cache_detail *cd,
1159 struct gssp_upcall_data *ud,
1160 uint64_t *handle)
1161{
1162 struct rsc rsci, *rscp = NULL;
1163 static atomic64_t ctxhctr;
1164 long long ctxh;
1165 struct gss_api_mech *gm = NULL;
1166 time_t expiry;
1167 int status = -EINVAL;
1168
1169 memset(&rsci, 0, sizeof(rsci));
1170 /* context handle */
1171 status = -ENOMEM;
1172 /* the handle needs to be just a unique id,
1173 * use a static counter */
1174 ctxh = atomic64_inc_return(&ctxhctr);
1175
1176 /* make a copy for the caller */
1177 *handle = ctxh;
1178
1179 /* make a copy for the rsc cache */
1180 if (dup_to_netobj(&rsci.handle, (char *)handle, sizeof(uint64_t)))
1181 goto out;
1182 rscp = rsc_lookup(cd, &rsci);
1183 if (!rscp)
1184 goto out;
1185
1186 /* creds */
1187 if (!ud->found_creds) {
1188 /* userspace seem buggy, we should always get at least a
1189 * mapping to nobody */
1190 dprintk("RPC: No creds found!\n");
1191 goto out;
1192 } else {
1193
1194 /* steal creds */
1195 rsci.cred = ud->creds;
1196 memset(&ud->creds, 0, sizeof(struct svc_cred));
1197
1198 status = -EOPNOTSUPP;
1199 /* get mech handle from OID */
1200 gm = gss_mech_get_by_OID(&ud->mech_oid);
1201 if (!gm)
1202 goto out;
1203 rsci.cred.cr_gss_mech = gm;
1204
1205 status = -EINVAL;
1206 /* mech-specific data: */
1207 status = gss_import_sec_context(ud->out_handle.data,
1208 ud->out_handle.len,
1209 gm, &rsci.mechctx,
1210 &expiry, GFP_KERNEL);
1211 if (status)
1212 goto out;
1213 }
1214
1215 rsci.h.expiry_time = expiry;
1216 rscp = rsc_update(cd, &rsci, rscp);
1217 status = 0;
1218out:
1219 rsc_free(&rsci);
1220 if (rscp)
1221 cache_put(&rscp->h, cd);
1222 else
1223 status = -ENOMEM;
1224 return status;
1225}
1226
1227static int svcauth_gss_proxy_init(struct svc_rqst *rqstp,
1228 struct rpc_gss_wire_cred *gc, __be32 *authp)
1229{
1230 struct kvec *resv = &rqstp->rq_res.head[0];
1231 struct xdr_netobj cli_handle;
1232 struct gssp_upcall_data ud;
1233 uint64_t handle;
1234 int status;
1235 int ret;
1236 struct net *net = rqstp->rq_xprt->xpt_net;
1237 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1238
1239 memset(&ud, 0, sizeof(ud));
1240 ret = gss_read_proxy_verf(rqstp, gc, authp,
1241 &ud.in_handle, &ud.in_token);
1242 if (ret)
1243 return ret;
1244
1245 ret = SVC_CLOSE;
1246
1247 /* Perform synchronous upcall to gss-proxy */
1248 status = gssp_accept_sec_context_upcall(net, &ud);
1249 if (status)
1250 goto out;
1251
1252 dprintk("RPC: svcauth_gss: gss major status = %d "
1253 "minor status = %d\n",
1254 ud.major_status, ud.minor_status);
1255
1256 switch (ud.major_status) {
1257 case GSS_S_CONTINUE_NEEDED:
1258 cli_handle = ud.out_handle;
1259 break;
1260 case GSS_S_COMPLETE:
1261 status = gss_proxy_save_rsc(sn->rsc_cache, &ud, &handle);
1262 if (status)
1263 goto out;
1264 cli_handle.data = (u8 *)&handle;
1265 cli_handle.len = sizeof(handle);
1266 break;
1267 default:
1268 ret = SVC_CLOSE;
1269 goto out;
1270 }
1271
1272 /* Got an answer to the upcall; use it: */
1273 if (gss_write_init_verf(sn->rsc_cache, rqstp,
1274 &cli_handle, &ud.major_status))
1275 goto out;
1276 if (gss_write_resv(resv, PAGE_SIZE,
1277 &cli_handle, &ud.out_token,
1278 ud.major_status, ud.minor_status))
1279 goto out;
1280
1281 ret = SVC_COMPLETE;
1282out:
1283 gssp_free_upcall_data(&ud);
1284 return ret;
1285}
1286
1287/*
1288 * Try to set the sn->use_gss_proxy variable to a new value. We only allow
1289 * it to be changed if it's currently undefined (-1). If it's any other value
1290 * then return -EBUSY unless the type wouldn't have changed anyway.
1291 */
1292static int set_gss_proxy(struct net *net, int type)
1293{
1294 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1295 int ret;
1296
1297 WARN_ON_ONCE(type != 0 && type != 1);
1298 ret = cmpxchg(&sn->use_gss_proxy, -1, type);
1299 if (ret != -1 && ret != type)
1300 return -EBUSY;
1301 return 0;
1302}
1303
1304static bool use_gss_proxy(struct net *net)
1305{
1306 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1307
1308 /* If use_gss_proxy is still undefined, then try to disable it */
1309 if (sn->use_gss_proxy == -1)
1310 set_gss_proxy(net, 0);
1311 return sn->use_gss_proxy;
1312}
1313
1314#ifdef CONFIG_PROC_FS
1315
1316static ssize_t write_gssp(struct file *file, const char __user *buf,
1317 size_t count, loff_t *ppos)
1318{
1319 struct net *net = PDE_DATA(file_inode(file));
1320 char tbuf[20];
1321 unsigned long i;
1322 int res;
1323
1324 if (*ppos || count > sizeof(tbuf)-1)
1325 return -EINVAL;
1326 if (copy_from_user(tbuf, buf, count))
1327 return -EFAULT;
1328
1329 tbuf[count] = 0;
1330 res = kstrtoul(tbuf, 0, &i);
1331 if (res)
1332 return res;
1333 if (i != 1)
1334 return -EINVAL;
1335 res = set_gssp_clnt(net);
1336 if (res)
1337 return res;
1338 res = set_gss_proxy(net, 1);
1339 if (res)
1340 return res;
1341 return count;
1342}
1343
1344static ssize_t read_gssp(struct file *file, char __user *buf,
1345 size_t count, loff_t *ppos)
1346{
1347 struct net *net = PDE_DATA(file_inode(file));
1348 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1349 unsigned long p = *ppos;
1350 char tbuf[10];
1351 size_t len;
1352
1353 snprintf(tbuf, sizeof(tbuf), "%d\n", sn->use_gss_proxy);
1354 len = strlen(tbuf);
1355 if (p >= len)
1356 return 0;
1357 len -= p;
1358 if (len > count)
1359 len = count;
1360 if (copy_to_user(buf, (void *)(tbuf+p), len))
1361 return -EFAULT;
1362 *ppos += len;
1363 return len;
1364}
1365
1366static const struct file_operations use_gss_proxy_ops = {
1367 .open = nonseekable_open,
1368 .write = write_gssp,
1369 .read = read_gssp,
1370};
1371
1372static int create_use_gss_proxy_proc_entry(struct net *net)
1373{
1374 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1375 struct proc_dir_entry **p = &sn->use_gssp_proc;
1376
1377 sn->use_gss_proxy = -1;
1378 *p = proc_create_data("use-gss-proxy", S_IFREG | 0600,
1379 sn->proc_net_rpc,
1380 &use_gss_proxy_ops, net);
1381 if (!*p)
1382 return -ENOMEM;
1383 init_gssp_clnt(sn);
1384 return 0;
1385}
1386
1387static void destroy_use_gss_proxy_proc_entry(struct net *net)
1388{
1389 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1390
1391 if (sn->use_gssp_proc) {
1392 remove_proc_entry("use-gss-proxy", sn->proc_net_rpc);
1393 clear_gssp_clnt(sn);
1394 }
1395}
1396#else /* CONFIG_PROC_FS */
1397
1398static int create_use_gss_proxy_proc_entry(struct net *net)
1399{
1400 return 0;
1401}
1402
1403static void destroy_use_gss_proxy_proc_entry(struct net *net) {}
1404
1405#endif /* CONFIG_PROC_FS */
1406
1407/*
1408 * Accept an rpcsec packet.
1409 * If context establishment, punt to user space
1410 * If data exchange, verify/decrypt
1411 * If context destruction, handle here
1412 * In the context establishment and destruction case we encode
1413 * response here and return SVC_COMPLETE.
1414 */
1415static int
1416svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
1417{
1418 struct kvec *argv = &rqstp->rq_arg.head[0];
1419 struct kvec *resv = &rqstp->rq_res.head[0];
1420 u32 crlen;
1421 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
1422 struct rpc_gss_wire_cred *gc;
1423 struct rsc *rsci = NULL;
1424 __be32 *rpcstart;
1425 __be32 *reject_stat = resv->iov_base + resv->iov_len;
1426 int ret;
1427 struct sunrpc_net *sn = net_generic(rqstp->rq_xprt->xpt_net, sunrpc_net_id);
1428
1429 dprintk("RPC: svcauth_gss: argv->iov_len = %zd\n",
1430 argv->iov_len);
1431
1432 *authp = rpc_autherr_badcred;
1433 if (!svcdata)
1434 svcdata = kmalloc(sizeof(*svcdata), GFP_KERNEL);
1435 if (!svcdata)
1436 goto auth_err;
1437 rqstp->rq_auth_data = svcdata;
1438 svcdata->verf_start = NULL;
1439 svcdata->rsci = NULL;
1440 gc = &svcdata->clcred;
1441
1442 /* start of rpc packet is 7 u32's back from here:
1443 * xid direction rpcversion prog vers proc flavour
1444 */
1445 rpcstart = argv->iov_base;
1446 rpcstart -= 7;
1447
1448 /* credential is:
1449 * version(==1), proc(0,1,2,3), seq, service (1,2,3), handle
1450 * at least 5 u32s, and is preceded by length, so that makes 6.
1451 */
1452
1453 if (argv->iov_len < 5 * 4)
1454 goto auth_err;
1455 crlen = svc_getnl(argv);
1456 if (svc_getnl(argv) != RPC_GSS_VERSION)
1457 goto auth_err;
1458 gc->gc_proc = svc_getnl(argv);
1459 gc->gc_seq = svc_getnl(argv);
1460 gc->gc_svc = svc_getnl(argv);
1461 if (svc_safe_getnetobj(argv, &gc->gc_ctx))
1462 goto auth_err;
1463 if (crlen != round_up_to_quad(gc->gc_ctx.len) + 5 * 4)
1464 goto auth_err;
1465
1466 if ((gc->gc_proc != RPC_GSS_PROC_DATA) && (rqstp->rq_proc != 0))
1467 goto auth_err;
1468
1469 *authp = rpc_autherr_badverf;
1470 switch (gc->gc_proc) {
1471 case RPC_GSS_PROC_INIT:
1472 case RPC_GSS_PROC_CONTINUE_INIT:
1473 if (use_gss_proxy(SVC_NET(rqstp)))
1474 return svcauth_gss_proxy_init(rqstp, gc, authp);
1475 else
1476 return svcauth_gss_legacy_init(rqstp, gc, authp);
1477 case RPC_GSS_PROC_DATA:
1478 case RPC_GSS_PROC_DESTROY:
1479 /* Look up the context, and check the verifier: */
1480 *authp = rpcsec_gsserr_credproblem;
1481 rsci = gss_svc_searchbyctx(sn->rsc_cache, &gc->gc_ctx);
1482 if (!rsci)
1483 goto auth_err;
1484 switch (gss_verify_header(rqstp, rsci, rpcstart, gc, authp)) {
1485 case SVC_OK:
1486 break;
1487 case SVC_DENIED:
1488 goto auth_err;
1489 case SVC_DROP:
1490 goto drop;
1491 }
1492 break;
1493 default:
1494 *authp = rpc_autherr_rejectedcred;
1495 goto auth_err;
1496 }
1497
1498 /* now act upon the command: */
1499 switch (gc->gc_proc) {
1500 case RPC_GSS_PROC_DESTROY:
1501 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
1502 goto auth_err;
1503 /* Delete the entry from the cache_list and call cache_put */
1504 sunrpc_cache_unhash(sn->rsc_cache, &rsci->h);
1505 if (resv->iov_len + 4 > PAGE_SIZE)
1506 goto drop;
1507 svc_putnl(resv, RPC_SUCCESS);
1508 goto complete;
1509 case RPC_GSS_PROC_DATA:
1510 *authp = rpcsec_gsserr_ctxproblem;
1511 svcdata->verf_start = resv->iov_base + resv->iov_len;
1512 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
1513 goto auth_err;
1514 rqstp->rq_cred = rsci->cred;
1515 get_group_info(rsci->cred.cr_group_info);
1516 *authp = rpc_autherr_badcred;
1517 switch (gc->gc_svc) {
1518 case RPC_GSS_SVC_NONE:
1519 break;
1520 case RPC_GSS_SVC_INTEGRITY:
1521 /* placeholders for length and seq. number: */
1522 svc_putnl(resv, 0);
1523 svc_putnl(resv, 0);
1524 if (unwrap_integ_data(rqstp, &rqstp->rq_arg,
1525 gc->gc_seq, rsci->mechctx))
1526 goto garbage_args;
1527 rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE;
1528 break;
1529 case RPC_GSS_SVC_PRIVACY:
1530 /* placeholders for length and seq. number: */
1531 svc_putnl(resv, 0);
1532 svc_putnl(resv, 0);
1533 if (unwrap_priv_data(rqstp, &rqstp->rq_arg,
1534 gc->gc_seq, rsci->mechctx))
1535 goto garbage_args;
1536 rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE * 2;
1537 break;
1538 default:
1539 goto auth_err;
1540 }
1541 svcdata->rsci = rsci;
1542 cache_get(&rsci->h);
1543 rqstp->rq_cred.cr_flavor = gss_svc_to_pseudoflavor(
1544 rsci->mechctx->mech_type,
1545 GSS_C_QOP_DEFAULT,
1546 gc->gc_svc);
1547 ret = SVC_OK;
1548 goto out;
1549 }
1550garbage_args:
1551 ret = SVC_GARBAGE;
1552 goto out;
1553auth_err:
1554 /* Restore write pointer to its original value: */
1555 xdr_ressize_check(rqstp, reject_stat);
1556 ret = SVC_DENIED;
1557 goto out;
1558complete:
1559 ret = SVC_COMPLETE;
1560 goto out;
1561drop:
1562 ret = SVC_CLOSE;
1563out:
1564 if (rsci)
1565 cache_put(&rsci->h, sn->rsc_cache);
1566 return ret;
1567}
1568
1569static __be32 *
1570svcauth_gss_prepare_to_wrap(struct xdr_buf *resbuf, struct gss_svc_data *gsd)
1571{
1572 __be32 *p;
1573 u32 verf_len;
1574
1575 p = gsd->verf_start;
1576 gsd->verf_start = NULL;
1577
1578 /* If the reply stat is nonzero, don't wrap: */
1579 if (*(p-1) != rpc_success)
1580 return NULL;
1581 /* Skip the verifier: */
1582 p += 1;
1583 verf_len = ntohl(*p++);
1584 p += XDR_QUADLEN(verf_len);
1585 /* move accept_stat to right place: */
1586 memcpy(p, p + 2, 4);
1587 /* Also don't wrap if the accept stat is nonzero: */
1588 if (*p != rpc_success) {
1589 resbuf->head[0].iov_len -= 2 * 4;
1590 return NULL;
1591 }
1592 p++;
1593 return p;
1594}
1595
1596static inline int
1597svcauth_gss_wrap_resp_integ(struct svc_rqst *rqstp)
1598{
1599 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1600 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1601 struct xdr_buf *resbuf = &rqstp->rq_res;
1602 struct xdr_buf integ_buf;
1603 struct xdr_netobj mic;
1604 struct kvec *resv;
1605 __be32 *p;
1606 int integ_offset, integ_len;
1607 int stat = -EINVAL;
1608
1609 p = svcauth_gss_prepare_to_wrap(resbuf, gsd);
1610 if (p == NULL)
1611 goto out;
1612 integ_offset = (u8 *)(p + 1) - (u8 *)resbuf->head[0].iov_base;
1613 integ_len = resbuf->len - integ_offset;
1614 BUG_ON(integ_len % 4);
1615 *p++ = htonl(integ_len);
1616 *p++ = htonl(gc->gc_seq);
1617 if (xdr_buf_subsegment(resbuf, &integ_buf, integ_offset, integ_len)) {
1618 WARN_ON_ONCE(1);
1619 goto out_err;
1620 }
1621 if (resbuf->tail[0].iov_base == NULL) {
1622 if (resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1623 goto out_err;
1624 resbuf->tail[0].iov_base = resbuf->head[0].iov_base
1625 + resbuf->head[0].iov_len;
1626 resbuf->tail[0].iov_len = 0;
1627 }
1628 resv = &resbuf->tail[0];
1629 mic.data = (u8 *)resv->iov_base + resv->iov_len + 4;
1630 if (gss_get_mic(gsd->rsci->mechctx, &integ_buf, &mic))
1631 goto out_err;
1632 svc_putnl(resv, mic.len);
1633 memset(mic.data + mic.len, 0,
1634 round_up_to_quad(mic.len) - mic.len);
1635 resv->iov_len += XDR_QUADLEN(mic.len) << 2;
1636 /* not strictly required: */
1637 resbuf->len += XDR_QUADLEN(mic.len) << 2;
1638 BUG_ON(resv->iov_len > PAGE_SIZE);
1639out:
1640 stat = 0;
1641out_err:
1642 return stat;
1643}
1644
1645static inline int
1646svcauth_gss_wrap_resp_priv(struct svc_rqst *rqstp)
1647{
1648 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1649 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1650 struct xdr_buf *resbuf = &rqstp->rq_res;
1651 struct page **inpages = NULL;
1652 __be32 *p, *len;
1653 int offset;
1654 int pad;
1655
1656 p = svcauth_gss_prepare_to_wrap(resbuf, gsd);
1657 if (p == NULL)
1658 return 0;
1659 len = p++;
1660 offset = (u8 *)p - (u8 *)resbuf->head[0].iov_base;
1661 *p++ = htonl(gc->gc_seq);
1662 inpages = resbuf->pages;
1663 /* XXX: Would be better to write some xdr helper functions for
1664 * nfs{2,3,4}xdr.c that place the data right, instead of copying: */
1665
1666 /*
1667 * If there is currently tail data, make sure there is
1668 * room for the head, tail, and 2 * RPC_MAX_AUTH_SIZE in
1669 * the page, and move the current tail data such that
1670 * there is RPC_MAX_AUTH_SIZE slack space available in
1671 * both the head and tail.
1672 */
1673 if (resbuf->tail[0].iov_base) {
1674 BUG_ON(resbuf->tail[0].iov_base >= resbuf->head[0].iov_base
1675 + PAGE_SIZE);
1676 BUG_ON(resbuf->tail[0].iov_base < resbuf->head[0].iov_base);
1677 if (resbuf->tail[0].iov_len + resbuf->head[0].iov_len
1678 + 2 * RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1679 return -ENOMEM;
1680 memmove(resbuf->tail[0].iov_base + RPC_MAX_AUTH_SIZE,
1681 resbuf->tail[0].iov_base,
1682 resbuf->tail[0].iov_len);
1683 resbuf->tail[0].iov_base += RPC_MAX_AUTH_SIZE;
1684 }
1685 /*
1686 * If there is no current tail data, make sure there is
1687 * room for the head data, and 2 * RPC_MAX_AUTH_SIZE in the
1688 * allotted page, and set up tail information such that there
1689 * is RPC_MAX_AUTH_SIZE slack space available in both the
1690 * head and tail.
1691 */
1692 if (resbuf->tail[0].iov_base == NULL) {
1693 if (resbuf->head[0].iov_len + 2*RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1694 return -ENOMEM;
1695 resbuf->tail[0].iov_base = resbuf->head[0].iov_base
1696 + resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE;
1697 resbuf->tail[0].iov_len = 0;
1698 }
1699 if (gss_wrap(gsd->rsci->mechctx, offset, resbuf, inpages))
1700 return -ENOMEM;
1701 *len = htonl(resbuf->len - offset);
1702 pad = 3 - ((resbuf->len - offset - 1)&3);
1703 p = (__be32 *)(resbuf->tail[0].iov_base + resbuf->tail[0].iov_len);
1704 memset(p, 0, pad);
1705 resbuf->tail[0].iov_len += pad;
1706 resbuf->len += pad;
1707 return 0;
1708}
1709
1710static int
1711svcauth_gss_release(struct svc_rqst *rqstp)
1712{
1713 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1714 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1715 struct xdr_buf *resbuf = &rqstp->rq_res;
1716 int stat = -EINVAL;
1717 struct sunrpc_net *sn = net_generic(rqstp->rq_xprt->xpt_net, sunrpc_net_id);
1718
1719 if (gc->gc_proc != RPC_GSS_PROC_DATA)
1720 goto out;
1721 /* Release can be called twice, but we only wrap once. */
1722 if (gsd->verf_start == NULL)
1723 goto out;
1724 /* normally not set till svc_send, but we need it here: */
1725 /* XXX: what for? Do we mess it up the moment we call svc_putu32
1726 * or whatever? */
1727 resbuf->len = total_buf_len(resbuf);
1728 switch (gc->gc_svc) {
1729 case RPC_GSS_SVC_NONE:
1730 break;
1731 case RPC_GSS_SVC_INTEGRITY:
1732 stat = svcauth_gss_wrap_resp_integ(rqstp);
1733 if (stat)
1734 goto out_err;
1735 break;
1736 case RPC_GSS_SVC_PRIVACY:
1737 stat = svcauth_gss_wrap_resp_priv(rqstp);
1738 if (stat)
1739 goto out_err;
1740 break;
1741 /*
1742 * For any other gc_svc value, svcauth_gss_accept() already set
1743 * the auth_error appropriately; just fall through:
1744 */
1745 }
1746
1747out:
1748 stat = 0;
1749out_err:
1750 if (rqstp->rq_client)
1751 auth_domain_put(rqstp->rq_client);
1752 rqstp->rq_client = NULL;
1753 if (rqstp->rq_gssclient)
1754 auth_domain_put(rqstp->rq_gssclient);
1755 rqstp->rq_gssclient = NULL;
1756 if (rqstp->rq_cred.cr_group_info)
1757 put_group_info(rqstp->rq_cred.cr_group_info);
1758 rqstp->rq_cred.cr_group_info = NULL;
1759 if (gsd->rsci)
1760 cache_put(&gsd->rsci->h, sn->rsc_cache);
1761 gsd->rsci = NULL;
1762
1763 return stat;
1764}
1765
1766static void
1767svcauth_gss_domain_release(struct auth_domain *dom)
1768{
1769 struct gss_domain *gd = container_of(dom, struct gss_domain, h);
1770
1771 kfree(dom->name);
1772 kfree(gd);
1773}
1774
1775static struct auth_ops svcauthops_gss = {
1776 .name = "rpcsec_gss",
1777 .owner = THIS_MODULE,
1778 .flavour = RPC_AUTH_GSS,
1779 .accept = svcauth_gss_accept,
1780 .release = svcauth_gss_release,
1781 .domain_release = svcauth_gss_domain_release,
1782 .set_client = svcauth_gss_set_client,
1783};
1784
1785static int rsi_cache_create_net(struct net *net)
1786{
1787 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1788 struct cache_detail *cd;
1789 int err;
1790
1791 cd = cache_create_net(&rsi_cache_template, net);
1792 if (IS_ERR(cd))
1793 return PTR_ERR(cd);
1794 err = cache_register_net(cd, net);
1795 if (err) {
1796 cache_destroy_net(cd, net);
1797 return err;
1798 }
1799 sn->rsi_cache = cd;
1800 return 0;
1801}
1802
1803static void rsi_cache_destroy_net(struct net *net)
1804{
1805 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1806 struct cache_detail *cd = sn->rsi_cache;
1807
1808 sn->rsi_cache = NULL;
1809 cache_purge(cd);
1810 cache_unregister_net(cd, net);
1811 cache_destroy_net(cd, net);
1812}
1813
1814static int rsc_cache_create_net(struct net *net)
1815{
1816 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1817 struct cache_detail *cd;
1818 int err;
1819
1820 cd = cache_create_net(&rsc_cache_template, net);
1821 if (IS_ERR(cd))
1822 return PTR_ERR(cd);
1823 err = cache_register_net(cd, net);
1824 if (err) {
1825 cache_destroy_net(cd, net);
1826 return err;
1827 }
1828 sn->rsc_cache = cd;
1829 return 0;
1830}
1831
1832static void rsc_cache_destroy_net(struct net *net)
1833{
1834 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1835 struct cache_detail *cd = sn->rsc_cache;
1836
1837 sn->rsc_cache = NULL;
1838 cache_purge(cd);
1839 cache_unregister_net(cd, net);
1840 cache_destroy_net(cd, net);
1841}
1842
1843int
1844gss_svc_init_net(struct net *net)
1845{
1846 int rv;
1847
1848 rv = rsc_cache_create_net(net);
1849 if (rv)
1850 return rv;
1851 rv = rsi_cache_create_net(net);
1852 if (rv)
1853 goto out1;
1854 rv = create_use_gss_proxy_proc_entry(net);
1855 if (rv)
1856 goto out2;
1857 return 0;
1858out2:
1859 destroy_use_gss_proxy_proc_entry(net);
1860out1:
1861 rsc_cache_destroy_net(net);
1862 return rv;
1863}
1864
1865void
1866gss_svc_shutdown_net(struct net *net)
1867{
1868 destroy_use_gss_proxy_proc_entry(net);
1869 rsi_cache_destroy_net(net);
1870 rsc_cache_destroy_net(net);
1871}
1872
1873int
1874gss_svc_init(void)
1875{
1876 return svc_auth_register(RPC_AUTH_GSS, &svcauthops_gss);
1877}
1878
1879void
1880gss_svc_shutdown(void)
1881{
1882 svc_auth_unregister(RPC_AUTH_GSS);
1883}