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