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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
53#include <trace/events/rpcgss.h>
54
55#include "gss_rpc_upcall.h"
56
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 struct rcu_head rcu_head;
80};
81
82static struct rsi *rsi_update(struct cache_detail *cd, struct rsi *new, struct rsi *old);
83static struct rsi *rsi_lookup(struct cache_detail *cd, struct rsi *item);
84
85static void rsi_free(struct rsi *rsii)
86{
87 kfree(rsii->in_handle.data);
88 kfree(rsii->in_token.data);
89 kfree(rsii->out_handle.data);
90 kfree(rsii->out_token.data);
91}
92
93static void rsi_free_rcu(struct rcu_head *head)
94{
95 struct rsi *rsii = container_of(head, struct rsi, rcu_head);
96
97 rsi_free(rsii);
98 kfree(rsii);
99}
100
101static void rsi_put(struct kref *ref)
102{
103 struct rsi *rsii = container_of(ref, struct rsi, h.ref);
104
105 call_rcu(&rsii->rcu_head, rsi_free_rcu);
106}
107
108static inline int rsi_hash(struct rsi *item)
109{
110 return hash_mem(item->in_handle.data, item->in_handle.len, RSI_HASHBITS)
111 ^ hash_mem(item->in_token.data, item->in_token.len, RSI_HASHBITS);
112}
113
114static int rsi_match(struct cache_head *a, struct cache_head *b)
115{
116 struct rsi *item = container_of(a, struct rsi, h);
117 struct rsi *tmp = container_of(b, struct rsi, h);
118 return netobj_equal(&item->in_handle, &tmp->in_handle) &&
119 netobj_equal(&item->in_token, &tmp->in_token);
120}
121
122static int dup_to_netobj(struct xdr_netobj *dst, char *src, int len)
123{
124 dst->len = len;
125 dst->data = (len ? kmemdup(src, len, GFP_KERNEL) : NULL);
126 if (len && !dst->data)
127 return -ENOMEM;
128 return 0;
129}
130
131static inline int dup_netobj(struct xdr_netobj *dst, struct xdr_netobj *src)
132{
133 return dup_to_netobj(dst, src->data, src->len);
134}
135
136static void rsi_init(struct cache_head *cnew, struct cache_head *citem)
137{
138 struct rsi *new = container_of(cnew, struct rsi, h);
139 struct rsi *item = container_of(citem, struct rsi, h);
140
141 new->out_handle.data = NULL;
142 new->out_handle.len = 0;
143 new->out_token.data = NULL;
144 new->out_token.len = 0;
145 new->in_handle.len = item->in_handle.len;
146 item->in_handle.len = 0;
147 new->in_token.len = item->in_token.len;
148 item->in_token.len = 0;
149 new->in_handle.data = item->in_handle.data;
150 item->in_handle.data = NULL;
151 new->in_token.data = item->in_token.data;
152 item->in_token.data = NULL;
153}
154
155static void update_rsi(struct cache_head *cnew, struct cache_head *citem)
156{
157 struct rsi *new = container_of(cnew, struct rsi, h);
158 struct rsi *item = container_of(citem, struct rsi, h);
159
160 BUG_ON(new->out_handle.data || new->out_token.data);
161 new->out_handle.len = item->out_handle.len;
162 item->out_handle.len = 0;
163 new->out_token.len = item->out_token.len;
164 item->out_token.len = 0;
165 new->out_handle.data = item->out_handle.data;
166 item->out_handle.data = NULL;
167 new->out_token.data = item->out_token.data;
168 item->out_token.data = NULL;
169
170 new->major_status = item->major_status;
171 new->minor_status = item->minor_status;
172}
173
174static struct cache_head *rsi_alloc(void)
175{
176 struct rsi *rsii = kmalloc(sizeof(*rsii), GFP_KERNEL);
177 if (rsii)
178 return &rsii->h;
179 else
180 return NULL;
181}
182
183static int rsi_upcall(struct cache_detail *cd, struct cache_head *h)
184{
185 return sunrpc_cache_pipe_upcall_timeout(cd, h);
186}
187
188static void rsi_request(struct cache_detail *cd,
189 struct cache_head *h,
190 char **bpp, int *blen)
191{
192 struct rsi *rsii = container_of(h, struct rsi, h);
193
194 qword_addhex(bpp, blen, rsii->in_handle.data, rsii->in_handle.len);
195 qword_addhex(bpp, blen, rsii->in_token.data, rsii->in_token.len);
196 (*bpp)[-1] = '\n';
197}
198
199static int rsi_parse(struct cache_detail *cd,
200 char *mesg, int mlen)
201{
202 /* context token expiry major minor context token */
203 char *buf = mesg;
204 char *ep;
205 int len;
206 struct rsi rsii, *rsip = NULL;
207 time64_t expiry;
208 int status = -EINVAL;
209
210 memset(&rsii, 0, sizeof(rsii));
211 /* handle */
212 len = qword_get(&mesg, buf, mlen);
213 if (len < 0)
214 goto out;
215 status = -ENOMEM;
216 if (dup_to_netobj(&rsii.in_handle, buf, len))
217 goto out;
218
219 /* token */
220 len = qword_get(&mesg, buf, mlen);
221 status = -EINVAL;
222 if (len < 0)
223 goto out;
224 status = -ENOMEM;
225 if (dup_to_netobj(&rsii.in_token, buf, len))
226 goto out;
227
228 rsip = rsi_lookup(cd, &rsii);
229 if (!rsip)
230 goto out;
231
232 rsii.h.flags = 0;
233 /* expiry */
234 expiry = get_expiry(&mesg);
235 status = -EINVAL;
236 if (expiry == 0)
237 goto out;
238
239 /* major/minor */
240 len = qword_get(&mesg, buf, mlen);
241 if (len <= 0)
242 goto out;
243 rsii.major_status = simple_strtoul(buf, &ep, 10);
244 if (*ep)
245 goto out;
246 len = qword_get(&mesg, buf, mlen);
247 if (len <= 0)
248 goto out;
249 rsii.minor_status = simple_strtoul(buf, &ep, 10);
250 if (*ep)
251 goto out;
252
253 /* out_handle */
254 len = qword_get(&mesg, buf, mlen);
255 if (len < 0)
256 goto out;
257 status = -ENOMEM;
258 if (dup_to_netobj(&rsii.out_handle, buf, len))
259 goto out;
260
261 /* out_token */
262 len = qword_get(&mesg, buf, mlen);
263 status = -EINVAL;
264 if (len < 0)
265 goto out;
266 status = -ENOMEM;
267 if (dup_to_netobj(&rsii.out_token, buf, len))
268 goto out;
269 rsii.h.expiry_time = expiry;
270 rsip = rsi_update(cd, &rsii, rsip);
271 status = 0;
272out:
273 rsi_free(&rsii);
274 if (rsip)
275 cache_put(&rsip->h, cd);
276 else
277 status = -ENOMEM;
278 return status;
279}
280
281static const struct cache_detail rsi_cache_template = {
282 .owner = THIS_MODULE,
283 .hash_size = RSI_HASHMAX,
284 .name = "auth.rpcsec.init",
285 .cache_put = rsi_put,
286 .cache_upcall = rsi_upcall,
287 .cache_request = rsi_request,
288 .cache_parse = rsi_parse,
289 .match = rsi_match,
290 .init = rsi_init,
291 .update = update_rsi,
292 .alloc = rsi_alloc,
293};
294
295static struct rsi *rsi_lookup(struct cache_detail *cd, struct rsi *item)
296{
297 struct cache_head *ch;
298 int hash = rsi_hash(item);
299
300 ch = sunrpc_cache_lookup_rcu(cd, &item->h, hash);
301 if (ch)
302 return container_of(ch, struct rsi, h);
303 else
304 return NULL;
305}
306
307static struct rsi *rsi_update(struct cache_detail *cd, struct rsi *new, struct rsi *old)
308{
309 struct cache_head *ch;
310 int hash = rsi_hash(new);
311
312 ch = sunrpc_cache_update(cd, &new->h,
313 &old->h, hash);
314 if (ch)
315 return container_of(ch, struct rsi, h);
316 else
317 return NULL;
318}
319
320
321/*
322 * The rpcsec_context cache is used to store a context that is
323 * used in data exchange.
324 * The key is a context handle. The content is:
325 * uid, gidlist, mechanism, service-set, mech-specific-data
326 */
327
328#define RSC_HASHBITS 10
329#define RSC_HASHMAX (1<<RSC_HASHBITS)
330
331#define GSS_SEQ_WIN 128
332
333struct gss_svc_seq_data {
334 /* highest seq number seen so far: */
335 u32 sd_max;
336 /* for i such that sd_max-GSS_SEQ_WIN < i <= sd_max, the i-th bit of
337 * sd_win is nonzero iff sequence number i has been seen already: */
338 unsigned long sd_win[GSS_SEQ_WIN/BITS_PER_LONG];
339 spinlock_t sd_lock;
340};
341
342struct rsc {
343 struct cache_head h;
344 struct xdr_netobj handle;
345 struct svc_cred cred;
346 struct gss_svc_seq_data seqdata;
347 struct gss_ctx *mechctx;
348 struct rcu_head rcu_head;
349};
350
351static struct rsc *rsc_update(struct cache_detail *cd, struct rsc *new, struct rsc *old);
352static struct rsc *rsc_lookup(struct cache_detail *cd, struct rsc *item);
353
354static void rsc_free(struct rsc *rsci)
355{
356 kfree(rsci->handle.data);
357 if (rsci->mechctx)
358 gss_delete_sec_context(&rsci->mechctx);
359 free_svc_cred(&rsci->cred);
360}
361
362static void rsc_free_rcu(struct rcu_head *head)
363{
364 struct rsc *rsci = container_of(head, struct rsc, rcu_head);
365
366 kfree(rsci->handle.data);
367 kfree(rsci);
368}
369
370static void rsc_put(struct kref *ref)
371{
372 struct rsc *rsci = container_of(ref, struct rsc, h.ref);
373
374 if (rsci->mechctx)
375 gss_delete_sec_context(&rsci->mechctx);
376 free_svc_cred(&rsci->cred);
377 call_rcu(&rsci->rcu_head, rsc_free_rcu);
378}
379
380static inline int
381rsc_hash(struct rsc *rsci)
382{
383 return hash_mem(rsci->handle.data, rsci->handle.len, RSC_HASHBITS);
384}
385
386static int
387rsc_match(struct cache_head *a, struct cache_head *b)
388{
389 struct rsc *new = container_of(a, struct rsc, h);
390 struct rsc *tmp = container_of(b, struct rsc, h);
391
392 return netobj_equal(&new->handle, &tmp->handle);
393}
394
395static void
396rsc_init(struct cache_head *cnew, struct cache_head *ctmp)
397{
398 struct rsc *new = container_of(cnew, struct rsc, h);
399 struct rsc *tmp = container_of(ctmp, struct rsc, h);
400
401 new->handle.len = tmp->handle.len;
402 tmp->handle.len = 0;
403 new->handle.data = tmp->handle.data;
404 tmp->handle.data = NULL;
405 new->mechctx = NULL;
406 init_svc_cred(&new->cred);
407}
408
409static void
410update_rsc(struct cache_head *cnew, struct cache_head *ctmp)
411{
412 struct rsc *new = container_of(cnew, struct rsc, h);
413 struct rsc *tmp = container_of(ctmp, struct rsc, h);
414
415 new->mechctx = tmp->mechctx;
416 tmp->mechctx = NULL;
417 memset(&new->seqdata, 0, sizeof(new->seqdata));
418 spin_lock_init(&new->seqdata.sd_lock);
419 new->cred = tmp->cred;
420 init_svc_cred(&tmp->cred);
421}
422
423static struct cache_head *
424rsc_alloc(void)
425{
426 struct rsc *rsci = kmalloc(sizeof(*rsci), GFP_KERNEL);
427 if (rsci)
428 return &rsci->h;
429 else
430 return NULL;
431}
432
433static int rsc_upcall(struct cache_detail *cd, struct cache_head *h)
434{
435 return -EINVAL;
436}
437
438static int rsc_parse(struct cache_detail *cd,
439 char *mesg, int mlen)
440{
441 /* contexthandle expiry [ uid gid N <n gids> mechname ...mechdata... ] */
442 char *buf = mesg;
443 int id;
444 int len, rv;
445 struct rsc rsci, *rscp = NULL;
446 time64_t expiry;
447 int status = -EINVAL;
448 struct gss_api_mech *gm = NULL;
449
450 memset(&rsci, 0, sizeof(rsci));
451 /* context handle */
452 len = qword_get(&mesg, buf, mlen);
453 if (len < 0) goto out;
454 status = -ENOMEM;
455 if (dup_to_netobj(&rsci.handle, buf, len))
456 goto out;
457
458 rsci.h.flags = 0;
459 /* expiry */
460 expiry = get_expiry(&mesg);
461 status = -EINVAL;
462 if (expiry == 0)
463 goto out;
464
465 rscp = rsc_lookup(cd, &rsci);
466 if (!rscp)
467 goto out;
468
469 /* uid, or NEGATIVE */
470 rv = get_int(&mesg, &id);
471 if (rv == -EINVAL)
472 goto out;
473 if (rv == -ENOENT)
474 set_bit(CACHE_NEGATIVE, &rsci.h.flags);
475 else {
476 int N, i;
477
478 /*
479 * NOTE: we skip uid_valid()/gid_valid() checks here:
480 * instead, * -1 id's are later mapped to the
481 * (export-specific) anonymous id by nfsd_setuser.
482 *
483 * (But supplementary gid's get no such special
484 * treatment so are checked for validity here.)
485 */
486 /* uid */
487 rsci.cred.cr_uid = make_kuid(current_user_ns(), id);
488
489 /* gid */
490 if (get_int(&mesg, &id))
491 goto out;
492 rsci.cred.cr_gid = make_kgid(current_user_ns(), id);
493
494 /* number of additional gid's */
495 if (get_int(&mesg, &N))
496 goto out;
497 if (N < 0 || N > NGROUPS_MAX)
498 goto out;
499 status = -ENOMEM;
500 rsci.cred.cr_group_info = groups_alloc(N);
501 if (rsci.cred.cr_group_info == NULL)
502 goto out;
503
504 /* gid's */
505 status = -EINVAL;
506 for (i=0; i<N; i++) {
507 kgid_t kgid;
508 if (get_int(&mesg, &id))
509 goto out;
510 kgid = make_kgid(current_user_ns(), id);
511 if (!gid_valid(kgid))
512 goto out;
513 rsci.cred.cr_group_info->gid[i] = kgid;
514 }
515 groups_sort(rsci.cred.cr_group_info);
516
517 /* mech name */
518 len = qword_get(&mesg, buf, mlen);
519 if (len < 0)
520 goto out;
521 gm = rsci.cred.cr_gss_mech = gss_mech_get_by_name(buf);
522 status = -EOPNOTSUPP;
523 if (!gm)
524 goto out;
525
526 status = -EINVAL;
527 /* mech-specific data: */
528 len = qword_get(&mesg, buf, mlen);
529 if (len < 0)
530 goto out;
531 status = gss_import_sec_context(buf, len, gm, &rsci.mechctx,
532 NULL, GFP_KERNEL);
533 if (status)
534 goto out;
535
536 /* get client name */
537 len = qword_get(&mesg, buf, mlen);
538 if (len > 0) {
539 rsci.cred.cr_principal = kstrdup(buf, GFP_KERNEL);
540 if (!rsci.cred.cr_principal) {
541 status = -ENOMEM;
542 goto out;
543 }
544 }
545
546 }
547 rsci.h.expiry_time = expiry;
548 rscp = rsc_update(cd, &rsci, rscp);
549 status = 0;
550out:
551 rsc_free(&rsci);
552 if (rscp)
553 cache_put(&rscp->h, cd);
554 else
555 status = -ENOMEM;
556 return status;
557}
558
559static const struct cache_detail rsc_cache_template = {
560 .owner = THIS_MODULE,
561 .hash_size = RSC_HASHMAX,
562 .name = "auth.rpcsec.context",
563 .cache_put = rsc_put,
564 .cache_upcall = rsc_upcall,
565 .cache_parse = rsc_parse,
566 .match = rsc_match,
567 .init = rsc_init,
568 .update = update_rsc,
569 .alloc = rsc_alloc,
570};
571
572static struct rsc *rsc_lookup(struct cache_detail *cd, struct rsc *item)
573{
574 struct cache_head *ch;
575 int hash = rsc_hash(item);
576
577 ch = sunrpc_cache_lookup_rcu(cd, &item->h, hash);
578 if (ch)
579 return container_of(ch, struct rsc, h);
580 else
581 return NULL;
582}
583
584static struct rsc *rsc_update(struct cache_detail *cd, struct rsc *new, struct rsc *old)
585{
586 struct cache_head *ch;
587 int hash = rsc_hash(new);
588
589 ch = sunrpc_cache_update(cd, &new->h,
590 &old->h, hash);
591 if (ch)
592 return container_of(ch, struct rsc, h);
593 else
594 return NULL;
595}
596
597
598static struct rsc *
599gss_svc_searchbyctx(struct cache_detail *cd, struct xdr_netobj *handle)
600{
601 struct rsc rsci;
602 struct rsc *found;
603
604 memset(&rsci, 0, sizeof(rsci));
605 if (dup_to_netobj(&rsci.handle, handle->data, handle->len))
606 return NULL;
607 found = rsc_lookup(cd, &rsci);
608 rsc_free(&rsci);
609 if (!found)
610 return NULL;
611 if (cache_check(cd, &found->h, NULL))
612 return NULL;
613 return found;
614}
615
616/**
617 * gss_check_seq_num - GSS sequence number window check
618 * @rqstp: RPC Call to use when reporting errors
619 * @rsci: cached GSS context state (updated on return)
620 * @seq_num: sequence number to check
621 *
622 * Implements sequence number algorithm as specified in
623 * RFC 2203, Section 5.3.3.1. "Context Management".
624 *
625 * Return values:
626 * %true: @rqstp's GSS sequence number is inside the window
627 * %false: @rqstp's GSS sequence number is outside the window
628 */
629static bool gss_check_seq_num(const struct svc_rqst *rqstp, struct rsc *rsci,
630 u32 seq_num)
631{
632 struct gss_svc_seq_data *sd = &rsci->seqdata;
633 bool result = false;
634
635 spin_lock(&sd->sd_lock);
636 if (seq_num > sd->sd_max) {
637 if (seq_num >= sd->sd_max + GSS_SEQ_WIN) {
638 memset(sd->sd_win, 0, sizeof(sd->sd_win));
639 sd->sd_max = seq_num;
640 } else while (sd->sd_max < seq_num) {
641 sd->sd_max++;
642 __clear_bit(sd->sd_max % GSS_SEQ_WIN, sd->sd_win);
643 }
644 __set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win);
645 goto ok;
646 } else if (seq_num <= sd->sd_max - GSS_SEQ_WIN) {
647 goto toolow;
648 }
649 if (__test_and_set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win))
650 goto alreadyseen;
651
652ok:
653 result = true;
654out:
655 spin_unlock(&sd->sd_lock);
656 return result;
657
658toolow:
659 trace_rpcgss_svc_seqno_low(rqstp, seq_num,
660 sd->sd_max - GSS_SEQ_WIN,
661 sd->sd_max);
662 goto out;
663alreadyseen:
664 trace_rpcgss_svc_seqno_seen(rqstp, seq_num);
665 goto out;
666}
667
668static inline u32 round_up_to_quad(u32 i)
669{
670 return (i + 3 ) & ~3;
671}
672
673static inline int
674svc_safe_getnetobj(struct kvec *argv, struct xdr_netobj *o)
675{
676 int l;
677
678 if (argv->iov_len < 4)
679 return -1;
680 o->len = svc_getnl(argv);
681 l = round_up_to_quad(o->len);
682 if (argv->iov_len < l)
683 return -1;
684 o->data = argv->iov_base;
685 argv->iov_base += l;
686 argv->iov_len -= l;
687 return 0;
688}
689
690static inline int
691svc_safe_putnetobj(struct kvec *resv, struct xdr_netobj *o)
692{
693 u8 *p;
694
695 if (resv->iov_len + 4 > PAGE_SIZE)
696 return -1;
697 svc_putnl(resv, o->len);
698 p = resv->iov_base + resv->iov_len;
699 resv->iov_len += round_up_to_quad(o->len);
700 if (resv->iov_len > PAGE_SIZE)
701 return -1;
702 memcpy(p, o->data, o->len);
703 memset(p + o->len, 0, round_up_to_quad(o->len) - o->len);
704 return 0;
705}
706
707/*
708 * Verify the checksum on the header and return SVC_OK on success.
709 * Otherwise, return SVC_DROP (in the case of a bad sequence number)
710 * or return SVC_DENIED and indicate error in authp.
711 */
712static int
713gss_verify_header(struct svc_rqst *rqstp, struct rsc *rsci,
714 __be32 *rpcstart, struct rpc_gss_wire_cred *gc, __be32 *authp)
715{
716 struct gss_ctx *ctx_id = rsci->mechctx;
717 struct xdr_buf rpchdr;
718 struct xdr_netobj checksum;
719 u32 flavor = 0;
720 struct kvec *argv = &rqstp->rq_arg.head[0];
721 struct kvec iov;
722
723 /* data to compute the checksum over: */
724 iov.iov_base = rpcstart;
725 iov.iov_len = (u8 *)argv->iov_base - (u8 *)rpcstart;
726 xdr_buf_from_iov(&iov, &rpchdr);
727
728 *authp = rpc_autherr_badverf;
729 if (argv->iov_len < 4)
730 return SVC_DENIED;
731 flavor = svc_getnl(argv);
732 if (flavor != RPC_AUTH_GSS)
733 return SVC_DENIED;
734 if (svc_safe_getnetobj(argv, &checksum))
735 return SVC_DENIED;
736
737 if (rqstp->rq_deferred) /* skip verification of revisited request */
738 return SVC_OK;
739 if (gss_verify_mic(ctx_id, &rpchdr, &checksum) != GSS_S_COMPLETE) {
740 *authp = rpcsec_gsserr_credproblem;
741 return SVC_DENIED;
742 }
743
744 if (gc->gc_seq > MAXSEQ) {
745 trace_rpcgss_svc_seqno_large(rqstp, gc->gc_seq);
746 *authp = rpcsec_gsserr_ctxproblem;
747 return SVC_DENIED;
748 }
749 if (!gss_check_seq_num(rqstp, rsci, gc->gc_seq))
750 return SVC_DROP;
751 return SVC_OK;
752}
753
754static int
755gss_write_null_verf(struct svc_rqst *rqstp)
756{
757 __be32 *p;
758
759 svc_putnl(rqstp->rq_res.head, RPC_AUTH_NULL);
760 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len;
761 /* don't really need to check if head->iov_len > PAGE_SIZE ... */
762 *p++ = 0;
763 if (!xdr_ressize_check(rqstp, p))
764 return -1;
765 return 0;
766}
767
768static int
769gss_write_verf(struct svc_rqst *rqstp, struct gss_ctx *ctx_id, u32 seq)
770{
771 __be32 *xdr_seq;
772 u32 maj_stat;
773 struct xdr_buf verf_data;
774 struct xdr_netobj mic;
775 __be32 *p;
776 struct kvec iov;
777 int err = -1;
778
779 svc_putnl(rqstp->rq_res.head, RPC_AUTH_GSS);
780 xdr_seq = kmalloc(4, GFP_KERNEL);
781 if (!xdr_seq)
782 return -1;
783 *xdr_seq = htonl(seq);
784
785 iov.iov_base = xdr_seq;
786 iov.iov_len = 4;
787 xdr_buf_from_iov(&iov, &verf_data);
788 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len;
789 mic.data = (u8 *)(p + 1);
790 maj_stat = gss_get_mic(ctx_id, &verf_data, &mic);
791 if (maj_stat != GSS_S_COMPLETE)
792 goto out;
793 *p++ = htonl(mic.len);
794 memset((u8 *)p + mic.len, 0, round_up_to_quad(mic.len) - mic.len);
795 p += XDR_QUADLEN(mic.len);
796 if (!xdr_ressize_check(rqstp, p))
797 goto out;
798 err = 0;
799out:
800 kfree(xdr_seq);
801 return err;
802}
803
804struct gss_domain {
805 struct auth_domain h;
806 u32 pseudoflavor;
807};
808
809static struct auth_domain *
810find_gss_auth_domain(struct gss_ctx *ctx, u32 svc)
811{
812 char *name;
813
814 name = gss_service_to_auth_domain_name(ctx->mech_type, svc);
815 if (!name)
816 return NULL;
817 return auth_domain_find(name);
818}
819
820static struct auth_ops svcauthops_gss;
821
822u32 svcauth_gss_flavor(struct auth_domain *dom)
823{
824 struct gss_domain *gd = container_of(dom, struct gss_domain, h);
825
826 return gd->pseudoflavor;
827}
828
829EXPORT_SYMBOL_GPL(svcauth_gss_flavor);
830
831struct auth_domain *
832svcauth_gss_register_pseudoflavor(u32 pseudoflavor, char * name)
833{
834 struct gss_domain *new;
835 struct auth_domain *test;
836 int stat = -ENOMEM;
837
838 new = kmalloc(sizeof(*new), GFP_KERNEL);
839 if (!new)
840 goto out;
841 kref_init(&new->h.ref);
842 new->h.name = kstrdup(name, GFP_KERNEL);
843 if (!new->h.name)
844 goto out_free_dom;
845 new->h.flavour = &svcauthops_gss;
846 new->pseudoflavor = pseudoflavor;
847
848 test = auth_domain_lookup(name, &new->h);
849 if (test != &new->h) {
850 pr_warn("svc: duplicate registration of gss pseudo flavour %s.\n",
851 name);
852 stat = -EADDRINUSE;
853 auth_domain_put(test);
854 goto out_free_name;
855 }
856 return test;
857
858out_free_name:
859 kfree(new->h.name);
860out_free_dom:
861 kfree(new);
862out:
863 return ERR_PTR(stat);
864}
865EXPORT_SYMBOL_GPL(svcauth_gss_register_pseudoflavor);
866
867static inline int
868read_u32_from_xdr_buf(struct xdr_buf *buf, int base, u32 *obj)
869{
870 __be32 raw;
871 int status;
872
873 status = read_bytes_from_xdr_buf(buf, base, &raw, sizeof(*obj));
874 if (status)
875 return status;
876 *obj = ntohl(raw);
877 return 0;
878}
879
880/* It would be nice if this bit of code could be shared with the client.
881 * Obstacles:
882 * The client shouldn't malloc(), would have to pass in own memory.
883 * The server uses base of head iovec as read pointer, while the
884 * client uses separate pointer. */
885static int
886unwrap_integ_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx)
887{
888 u32 integ_len, rseqno, maj_stat;
889 int stat = -EINVAL;
890 struct xdr_netobj mic;
891 struct xdr_buf integ_buf;
892
893 mic.data = NULL;
894
895 /* NFS READ normally uses splice to send data in-place. However
896 * the data in cache can change after the reply's MIC is computed
897 * but before the RPC reply is sent. To prevent the client from
898 * rejecting the server-computed MIC in this somewhat rare case,
899 * do not use splice with the GSS integrity service.
900 */
901 clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
902
903 /* Did we already verify the signature on the original pass through? */
904 if (rqstp->rq_deferred)
905 return 0;
906
907 integ_len = svc_getnl(&buf->head[0]);
908 if (integ_len & 3)
909 goto unwrap_failed;
910 if (integ_len > buf->len)
911 goto unwrap_failed;
912 if (xdr_buf_subsegment(buf, &integ_buf, 0, integ_len))
913 goto unwrap_failed;
914
915 /* copy out mic... */
916 if (read_u32_from_xdr_buf(buf, integ_len, &mic.len))
917 goto unwrap_failed;
918 if (mic.len > RPC_MAX_AUTH_SIZE)
919 goto unwrap_failed;
920 mic.data = kmalloc(mic.len, GFP_KERNEL);
921 if (!mic.data)
922 goto unwrap_failed;
923 if (read_bytes_from_xdr_buf(buf, integ_len + 4, mic.data, mic.len))
924 goto unwrap_failed;
925 maj_stat = gss_verify_mic(ctx, &integ_buf, &mic);
926 if (maj_stat != GSS_S_COMPLETE)
927 goto bad_mic;
928 rseqno = svc_getnl(&buf->head[0]);
929 if (rseqno != seq)
930 goto bad_seqno;
931 /* trim off the mic and padding at the end before returning */
932 xdr_buf_trim(buf, round_up_to_quad(mic.len) + 4);
933 stat = 0;
934out:
935 kfree(mic.data);
936 return stat;
937
938unwrap_failed:
939 trace_rpcgss_svc_unwrap_failed(rqstp);
940 goto out;
941bad_seqno:
942 trace_rpcgss_svc_seqno_bad(rqstp, seq, rseqno);
943 goto out;
944bad_mic:
945 trace_rpcgss_svc_mic(rqstp, maj_stat);
946 goto out;
947}
948
949static inline int
950total_buf_len(struct xdr_buf *buf)
951{
952 return buf->head[0].iov_len + buf->page_len + buf->tail[0].iov_len;
953}
954
955static void
956fix_priv_head(struct xdr_buf *buf, int pad)
957{
958 if (buf->page_len == 0) {
959 /* We need to adjust head and buf->len in tandem in this
960 * case to make svc_defer() work--it finds the original
961 * buffer start using buf->len - buf->head[0].iov_len. */
962 buf->head[0].iov_len -= pad;
963 }
964}
965
966static int
967unwrap_priv_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx)
968{
969 u32 priv_len, maj_stat;
970 int pad, remaining_len, offset;
971 u32 rseqno;
972
973 clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
974
975 priv_len = svc_getnl(&buf->head[0]);
976 if (rqstp->rq_deferred) {
977 /* Already decrypted last time through! The sequence number
978 * check at out_seq is unnecessary but harmless: */
979 goto out_seq;
980 }
981 /* buf->len is the number of bytes from the original start of the
982 * request to the end, where head[0].iov_len is just the bytes
983 * not yet read from the head, so these two values are different: */
984 remaining_len = total_buf_len(buf);
985 if (priv_len > remaining_len)
986 goto unwrap_failed;
987 pad = remaining_len - priv_len;
988 buf->len -= pad;
989 fix_priv_head(buf, pad);
990
991 maj_stat = gss_unwrap(ctx, 0, priv_len, buf);
992 pad = priv_len - buf->len;
993 /* The upper layers assume the buffer is aligned on 4-byte boundaries.
994 * In the krb5p case, at least, the data ends up offset, so we need to
995 * move it around. */
996 /* XXX: This is very inefficient. It would be better to either do
997 * this while we encrypt, or maybe in the receive code, if we can peak
998 * ahead and work out the service and mechanism there. */
999 offset = xdr_pad_size(buf->head[0].iov_len);
1000 if (offset) {
1001 buf->buflen = RPCSVC_MAXPAYLOAD;
1002 xdr_shift_buf(buf, offset);
1003 fix_priv_head(buf, pad);
1004 }
1005 if (maj_stat != GSS_S_COMPLETE)
1006 goto bad_unwrap;
1007out_seq:
1008 rseqno = svc_getnl(&buf->head[0]);
1009 if (rseqno != seq)
1010 goto bad_seqno;
1011 return 0;
1012
1013unwrap_failed:
1014 trace_rpcgss_svc_unwrap_failed(rqstp);
1015 return -EINVAL;
1016bad_seqno:
1017 trace_rpcgss_svc_seqno_bad(rqstp, seq, rseqno);
1018 return -EINVAL;
1019bad_unwrap:
1020 trace_rpcgss_svc_unwrap(rqstp, maj_stat);
1021 return -EINVAL;
1022}
1023
1024struct gss_svc_data {
1025 /* decoded gss client cred: */
1026 struct rpc_gss_wire_cred clcred;
1027 /* save a pointer to the beginning of the encoded verifier,
1028 * for use in encryption/checksumming in svcauth_gss_release: */
1029 __be32 *verf_start;
1030 struct rsc *rsci;
1031};
1032
1033static int
1034svcauth_gss_set_client(struct svc_rqst *rqstp)
1035{
1036 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
1037 struct rsc *rsci = svcdata->rsci;
1038 struct rpc_gss_wire_cred *gc = &svcdata->clcred;
1039 int stat;
1040
1041 /*
1042 * A gss export can be specified either by:
1043 * export *(sec=krb5,rw)
1044 * or by
1045 * export gss/krb5(rw)
1046 * The latter is deprecated; but for backwards compatibility reasons
1047 * the nfsd code will still fall back on trying it if the former
1048 * doesn't work; so we try to make both available to nfsd, below.
1049 */
1050 rqstp->rq_gssclient = find_gss_auth_domain(rsci->mechctx, gc->gc_svc);
1051 if (rqstp->rq_gssclient == NULL)
1052 return SVC_DENIED;
1053 stat = svcauth_unix_set_client(rqstp);
1054 if (stat == SVC_DROP || stat == SVC_CLOSE)
1055 return stat;
1056 return SVC_OK;
1057}
1058
1059static inline int
1060gss_write_init_verf(struct cache_detail *cd, struct svc_rqst *rqstp,
1061 struct xdr_netobj *out_handle, int *major_status)
1062{
1063 struct rsc *rsci;
1064 int rc;
1065
1066 if (*major_status != GSS_S_COMPLETE)
1067 return gss_write_null_verf(rqstp);
1068 rsci = gss_svc_searchbyctx(cd, out_handle);
1069 if (rsci == NULL) {
1070 *major_status = GSS_S_NO_CONTEXT;
1071 return gss_write_null_verf(rqstp);
1072 }
1073 rc = gss_write_verf(rqstp, rsci->mechctx, GSS_SEQ_WIN);
1074 cache_put(&rsci->h, cd);
1075 return rc;
1076}
1077
1078static inline int
1079gss_read_common_verf(struct rpc_gss_wire_cred *gc,
1080 struct kvec *argv, __be32 *authp,
1081 struct xdr_netobj *in_handle)
1082{
1083 /* Read the verifier; should be NULL: */
1084 *authp = rpc_autherr_badverf;
1085 if (argv->iov_len < 2 * 4)
1086 return SVC_DENIED;
1087 if (svc_getnl(argv) != RPC_AUTH_NULL)
1088 return SVC_DENIED;
1089 if (svc_getnl(argv) != 0)
1090 return SVC_DENIED;
1091 /* Martial context handle and token for upcall: */
1092 *authp = rpc_autherr_badcred;
1093 if (gc->gc_proc == RPC_GSS_PROC_INIT && gc->gc_ctx.len != 0)
1094 return SVC_DENIED;
1095 if (dup_netobj(in_handle, &gc->gc_ctx))
1096 return SVC_CLOSE;
1097 *authp = rpc_autherr_badverf;
1098
1099 return 0;
1100}
1101
1102static inline int
1103gss_read_verf(struct rpc_gss_wire_cred *gc,
1104 struct kvec *argv, __be32 *authp,
1105 struct xdr_netobj *in_handle,
1106 struct xdr_netobj *in_token)
1107{
1108 struct xdr_netobj tmpobj;
1109 int res;
1110
1111 res = gss_read_common_verf(gc, argv, authp, in_handle);
1112 if (res)
1113 return res;
1114
1115 if (svc_safe_getnetobj(argv, &tmpobj)) {
1116 kfree(in_handle->data);
1117 return SVC_DENIED;
1118 }
1119 if (dup_netobj(in_token, &tmpobj)) {
1120 kfree(in_handle->data);
1121 return SVC_CLOSE;
1122 }
1123
1124 return 0;
1125}
1126
1127static void gss_free_in_token_pages(struct gssp_in_token *in_token)
1128{
1129 u32 inlen;
1130 int i;
1131
1132 i = 0;
1133 inlen = in_token->page_len;
1134 while (inlen) {
1135 if (in_token->pages[i])
1136 put_page(in_token->pages[i]);
1137 inlen -= inlen > PAGE_SIZE ? PAGE_SIZE : inlen;
1138 }
1139
1140 kfree(in_token->pages);
1141 in_token->pages = NULL;
1142}
1143
1144static int gss_read_proxy_verf(struct svc_rqst *rqstp,
1145 struct rpc_gss_wire_cred *gc, __be32 *authp,
1146 struct xdr_netobj *in_handle,
1147 struct gssp_in_token *in_token)
1148{
1149 struct kvec *argv = &rqstp->rq_arg.head[0];
1150 unsigned int page_base, length;
1151 int pages, i, res;
1152 size_t inlen;
1153
1154 res = gss_read_common_verf(gc, argv, authp, in_handle);
1155 if (res)
1156 return res;
1157
1158 inlen = svc_getnl(argv);
1159 if (inlen > (argv->iov_len + rqstp->rq_arg.page_len))
1160 return SVC_DENIED;
1161
1162 pages = DIV_ROUND_UP(inlen, PAGE_SIZE);
1163 in_token->pages = kcalloc(pages, sizeof(struct page *), GFP_KERNEL);
1164 if (!in_token->pages)
1165 return SVC_DENIED;
1166 in_token->page_base = 0;
1167 in_token->page_len = inlen;
1168 for (i = 0; i < pages; i++) {
1169 in_token->pages[i] = alloc_page(GFP_KERNEL);
1170 if (!in_token->pages[i]) {
1171 gss_free_in_token_pages(in_token);
1172 return SVC_DENIED;
1173 }
1174 }
1175
1176 length = min_t(unsigned int, inlen, argv->iov_len);
1177 memcpy(page_address(in_token->pages[0]), argv->iov_base, length);
1178 inlen -= length;
1179
1180 i = 1;
1181 page_base = rqstp->rq_arg.page_base;
1182 while (inlen) {
1183 length = min_t(unsigned int, inlen, PAGE_SIZE);
1184 memcpy(page_address(in_token->pages[i]),
1185 page_address(rqstp->rq_arg.pages[i]) + page_base,
1186 length);
1187
1188 inlen -= length;
1189 page_base = 0;
1190 i++;
1191 }
1192 return 0;
1193}
1194
1195static inline int
1196gss_write_resv(struct kvec *resv, size_t size_limit,
1197 struct xdr_netobj *out_handle, struct xdr_netobj *out_token,
1198 int major_status, int minor_status)
1199{
1200 if (resv->iov_len + 4 > size_limit)
1201 return -1;
1202 svc_putnl(resv, RPC_SUCCESS);
1203 if (svc_safe_putnetobj(resv, out_handle))
1204 return -1;
1205 if (resv->iov_len + 3 * 4 > size_limit)
1206 return -1;
1207 svc_putnl(resv, major_status);
1208 svc_putnl(resv, minor_status);
1209 svc_putnl(resv, GSS_SEQ_WIN);
1210 if (svc_safe_putnetobj(resv, out_token))
1211 return -1;
1212 return 0;
1213}
1214
1215/*
1216 * Having read the cred already and found we're in the context
1217 * initiation case, read the verifier and initiate (or check the results
1218 * of) upcalls to userspace for help with context initiation. If
1219 * the upcall results are available, write the verifier and result.
1220 * Otherwise, drop the request pending an answer to the upcall.
1221 */
1222static int svcauth_gss_legacy_init(struct svc_rqst *rqstp,
1223 struct rpc_gss_wire_cred *gc, __be32 *authp)
1224{
1225 struct kvec *argv = &rqstp->rq_arg.head[0];
1226 struct kvec *resv = &rqstp->rq_res.head[0];
1227 struct rsi *rsip, rsikey;
1228 int ret;
1229 struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id);
1230
1231 memset(&rsikey, 0, sizeof(rsikey));
1232 ret = gss_read_verf(gc, argv, authp,
1233 &rsikey.in_handle, &rsikey.in_token);
1234 if (ret)
1235 return ret;
1236
1237 /* Perform upcall, or find upcall result: */
1238 rsip = rsi_lookup(sn->rsi_cache, &rsikey);
1239 rsi_free(&rsikey);
1240 if (!rsip)
1241 return SVC_CLOSE;
1242 if (cache_check(sn->rsi_cache, &rsip->h, &rqstp->rq_chandle) < 0)
1243 /* No upcall result: */
1244 return SVC_CLOSE;
1245
1246 ret = SVC_CLOSE;
1247 /* Got an answer to the upcall; use it: */
1248 if (gss_write_init_verf(sn->rsc_cache, rqstp,
1249 &rsip->out_handle, &rsip->major_status))
1250 goto out;
1251 if (gss_write_resv(resv, PAGE_SIZE,
1252 &rsip->out_handle, &rsip->out_token,
1253 rsip->major_status, rsip->minor_status))
1254 goto out;
1255
1256 ret = SVC_COMPLETE;
1257out:
1258 cache_put(&rsip->h, sn->rsi_cache);
1259 return ret;
1260}
1261
1262static int gss_proxy_save_rsc(struct cache_detail *cd,
1263 struct gssp_upcall_data *ud,
1264 uint64_t *handle)
1265{
1266 struct rsc rsci, *rscp = NULL;
1267 static atomic64_t ctxhctr;
1268 long long ctxh;
1269 struct gss_api_mech *gm = NULL;
1270 time64_t expiry;
1271 int status = -EINVAL;
1272
1273 memset(&rsci, 0, sizeof(rsci));
1274 /* context handle */
1275 status = -ENOMEM;
1276 /* the handle needs to be just a unique id,
1277 * use a static counter */
1278 ctxh = atomic64_inc_return(&ctxhctr);
1279
1280 /* make a copy for the caller */
1281 *handle = ctxh;
1282
1283 /* make a copy for the rsc cache */
1284 if (dup_to_netobj(&rsci.handle, (char *)handle, sizeof(uint64_t)))
1285 goto out;
1286 rscp = rsc_lookup(cd, &rsci);
1287 if (!rscp)
1288 goto out;
1289
1290 /* creds */
1291 if (!ud->found_creds) {
1292 /* userspace seem buggy, we should always get at least a
1293 * mapping to nobody */
1294 goto out;
1295 } else {
1296 struct timespec64 boot;
1297
1298 /* steal creds */
1299 rsci.cred = ud->creds;
1300 memset(&ud->creds, 0, sizeof(struct svc_cred));
1301
1302 status = -EOPNOTSUPP;
1303 /* get mech handle from OID */
1304 gm = gss_mech_get_by_OID(&ud->mech_oid);
1305 if (!gm)
1306 goto out;
1307 rsci.cred.cr_gss_mech = gm;
1308
1309 status = -EINVAL;
1310 /* mech-specific data: */
1311 status = gss_import_sec_context(ud->out_handle.data,
1312 ud->out_handle.len,
1313 gm, &rsci.mechctx,
1314 &expiry, GFP_KERNEL);
1315 if (status)
1316 goto out;
1317
1318 getboottime64(&boot);
1319 expiry -= boot.tv_sec;
1320 }
1321
1322 rsci.h.expiry_time = expiry;
1323 rscp = rsc_update(cd, &rsci, rscp);
1324 status = 0;
1325out:
1326 rsc_free(&rsci);
1327 if (rscp)
1328 cache_put(&rscp->h, cd);
1329 else
1330 status = -ENOMEM;
1331 return status;
1332}
1333
1334static int svcauth_gss_proxy_init(struct svc_rqst *rqstp,
1335 struct rpc_gss_wire_cred *gc, __be32 *authp)
1336{
1337 struct kvec *resv = &rqstp->rq_res.head[0];
1338 struct xdr_netobj cli_handle;
1339 struct gssp_upcall_data ud;
1340 uint64_t handle;
1341 int status;
1342 int ret;
1343 struct net *net = SVC_NET(rqstp);
1344 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1345
1346 memset(&ud, 0, sizeof(ud));
1347 ret = gss_read_proxy_verf(rqstp, gc, authp,
1348 &ud.in_handle, &ud.in_token);
1349 if (ret)
1350 return ret;
1351
1352 ret = SVC_CLOSE;
1353
1354 /* Perform synchronous upcall to gss-proxy */
1355 status = gssp_accept_sec_context_upcall(net, &ud);
1356 if (status)
1357 goto out;
1358
1359 trace_rpcgss_svc_accept_upcall(rqstp, ud.major_status, ud.minor_status);
1360
1361 switch (ud.major_status) {
1362 case GSS_S_CONTINUE_NEEDED:
1363 cli_handle = ud.out_handle;
1364 break;
1365 case GSS_S_COMPLETE:
1366 status = gss_proxy_save_rsc(sn->rsc_cache, &ud, &handle);
1367 if (status)
1368 goto out;
1369 cli_handle.data = (u8 *)&handle;
1370 cli_handle.len = sizeof(handle);
1371 break;
1372 default:
1373 goto out;
1374 }
1375
1376 /* Got an answer to the upcall; use it: */
1377 if (gss_write_init_verf(sn->rsc_cache, rqstp,
1378 &cli_handle, &ud.major_status))
1379 goto out;
1380 if (gss_write_resv(resv, PAGE_SIZE,
1381 &cli_handle, &ud.out_token,
1382 ud.major_status, ud.minor_status))
1383 goto out;
1384
1385 ret = SVC_COMPLETE;
1386out:
1387 gss_free_in_token_pages(&ud.in_token);
1388 gssp_free_upcall_data(&ud);
1389 return ret;
1390}
1391
1392/*
1393 * Try to set the sn->use_gss_proxy variable to a new value. We only allow
1394 * it to be changed if it's currently undefined (-1). If it's any other value
1395 * then return -EBUSY unless the type wouldn't have changed anyway.
1396 */
1397static int set_gss_proxy(struct net *net, int type)
1398{
1399 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1400 int ret;
1401
1402 WARN_ON_ONCE(type != 0 && type != 1);
1403 ret = cmpxchg(&sn->use_gss_proxy, -1, type);
1404 if (ret != -1 && ret != type)
1405 return -EBUSY;
1406 return 0;
1407}
1408
1409static bool use_gss_proxy(struct net *net)
1410{
1411 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1412
1413 /* If use_gss_proxy is still undefined, then try to disable it */
1414 if (sn->use_gss_proxy == -1)
1415 set_gss_proxy(net, 0);
1416 return sn->use_gss_proxy;
1417}
1418
1419#ifdef CONFIG_PROC_FS
1420
1421static ssize_t write_gssp(struct file *file, const char __user *buf,
1422 size_t count, loff_t *ppos)
1423{
1424 struct net *net = PDE_DATA(file_inode(file));
1425 char tbuf[20];
1426 unsigned long i;
1427 int res;
1428
1429 if (*ppos || count > sizeof(tbuf)-1)
1430 return -EINVAL;
1431 if (copy_from_user(tbuf, buf, count))
1432 return -EFAULT;
1433
1434 tbuf[count] = 0;
1435 res = kstrtoul(tbuf, 0, &i);
1436 if (res)
1437 return res;
1438 if (i != 1)
1439 return -EINVAL;
1440 res = set_gssp_clnt(net);
1441 if (res)
1442 return res;
1443 res = set_gss_proxy(net, 1);
1444 if (res)
1445 return res;
1446 return count;
1447}
1448
1449static ssize_t read_gssp(struct file *file, char __user *buf,
1450 size_t count, loff_t *ppos)
1451{
1452 struct net *net = PDE_DATA(file_inode(file));
1453 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1454 unsigned long p = *ppos;
1455 char tbuf[10];
1456 size_t len;
1457
1458 snprintf(tbuf, sizeof(tbuf), "%d\n", sn->use_gss_proxy);
1459 len = strlen(tbuf);
1460 if (p >= len)
1461 return 0;
1462 len -= p;
1463 if (len > count)
1464 len = count;
1465 if (copy_to_user(buf, (void *)(tbuf+p), len))
1466 return -EFAULT;
1467 *ppos += len;
1468 return len;
1469}
1470
1471static const struct proc_ops use_gss_proxy_proc_ops = {
1472 .proc_open = nonseekable_open,
1473 .proc_write = write_gssp,
1474 .proc_read = read_gssp,
1475};
1476
1477static int create_use_gss_proxy_proc_entry(struct net *net)
1478{
1479 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1480 struct proc_dir_entry **p = &sn->use_gssp_proc;
1481
1482 sn->use_gss_proxy = -1;
1483 *p = proc_create_data("use-gss-proxy", S_IFREG | 0600,
1484 sn->proc_net_rpc,
1485 &use_gss_proxy_proc_ops, net);
1486 if (!*p)
1487 return -ENOMEM;
1488 init_gssp_clnt(sn);
1489 return 0;
1490}
1491
1492static void destroy_use_gss_proxy_proc_entry(struct net *net)
1493{
1494 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1495
1496 if (sn->use_gssp_proc) {
1497 remove_proc_entry("use-gss-proxy", sn->proc_net_rpc);
1498 clear_gssp_clnt(sn);
1499 }
1500}
1501#else /* CONFIG_PROC_FS */
1502
1503static int create_use_gss_proxy_proc_entry(struct net *net)
1504{
1505 return 0;
1506}
1507
1508static void destroy_use_gss_proxy_proc_entry(struct net *net) {}
1509
1510#endif /* CONFIG_PROC_FS */
1511
1512/*
1513 * Accept an rpcsec packet.
1514 * If context establishment, punt to user space
1515 * If data exchange, verify/decrypt
1516 * If context destruction, handle here
1517 * In the context establishment and destruction case we encode
1518 * response here and return SVC_COMPLETE.
1519 */
1520static int
1521svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
1522{
1523 struct kvec *argv = &rqstp->rq_arg.head[0];
1524 struct kvec *resv = &rqstp->rq_res.head[0];
1525 u32 crlen;
1526 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
1527 struct rpc_gss_wire_cred *gc;
1528 struct rsc *rsci = NULL;
1529 __be32 *rpcstart;
1530 __be32 *reject_stat = resv->iov_base + resv->iov_len;
1531 int ret;
1532 struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id);
1533
1534 *authp = rpc_autherr_badcred;
1535 if (!svcdata)
1536 svcdata = kmalloc(sizeof(*svcdata), GFP_KERNEL);
1537 if (!svcdata)
1538 goto auth_err;
1539 rqstp->rq_auth_data = svcdata;
1540 svcdata->verf_start = NULL;
1541 svcdata->rsci = NULL;
1542 gc = &svcdata->clcred;
1543
1544 /* start of rpc packet is 7 u32's back from here:
1545 * xid direction rpcversion prog vers proc flavour
1546 */
1547 rpcstart = argv->iov_base;
1548 rpcstart -= 7;
1549
1550 /* credential is:
1551 * version(==1), proc(0,1,2,3), seq, service (1,2,3), handle
1552 * at least 5 u32s, and is preceded by length, so that makes 6.
1553 */
1554
1555 if (argv->iov_len < 5 * 4)
1556 goto auth_err;
1557 crlen = svc_getnl(argv);
1558 if (svc_getnl(argv) != RPC_GSS_VERSION)
1559 goto auth_err;
1560 gc->gc_proc = svc_getnl(argv);
1561 gc->gc_seq = svc_getnl(argv);
1562 gc->gc_svc = svc_getnl(argv);
1563 if (svc_safe_getnetobj(argv, &gc->gc_ctx))
1564 goto auth_err;
1565 if (crlen != round_up_to_quad(gc->gc_ctx.len) + 5 * 4)
1566 goto auth_err;
1567
1568 if ((gc->gc_proc != RPC_GSS_PROC_DATA) && (rqstp->rq_proc != 0))
1569 goto auth_err;
1570
1571 *authp = rpc_autherr_badverf;
1572 switch (gc->gc_proc) {
1573 case RPC_GSS_PROC_INIT:
1574 case RPC_GSS_PROC_CONTINUE_INIT:
1575 if (use_gss_proxy(SVC_NET(rqstp)))
1576 return svcauth_gss_proxy_init(rqstp, gc, authp);
1577 else
1578 return svcauth_gss_legacy_init(rqstp, gc, authp);
1579 case RPC_GSS_PROC_DATA:
1580 case RPC_GSS_PROC_DESTROY:
1581 /* Look up the context, and check the verifier: */
1582 *authp = rpcsec_gsserr_credproblem;
1583 rsci = gss_svc_searchbyctx(sn->rsc_cache, &gc->gc_ctx);
1584 if (!rsci)
1585 goto auth_err;
1586 switch (gss_verify_header(rqstp, rsci, rpcstart, gc, authp)) {
1587 case SVC_OK:
1588 break;
1589 case SVC_DENIED:
1590 goto auth_err;
1591 case SVC_DROP:
1592 goto drop;
1593 }
1594 break;
1595 default:
1596 *authp = rpc_autherr_rejectedcred;
1597 goto auth_err;
1598 }
1599
1600 /* now act upon the command: */
1601 switch (gc->gc_proc) {
1602 case RPC_GSS_PROC_DESTROY:
1603 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
1604 goto auth_err;
1605 /* Delete the entry from the cache_list and call cache_put */
1606 sunrpc_cache_unhash(sn->rsc_cache, &rsci->h);
1607 if (resv->iov_len + 4 > PAGE_SIZE)
1608 goto drop;
1609 svc_putnl(resv, RPC_SUCCESS);
1610 goto complete;
1611 case RPC_GSS_PROC_DATA:
1612 *authp = rpcsec_gsserr_ctxproblem;
1613 svcdata->verf_start = resv->iov_base + resv->iov_len;
1614 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
1615 goto auth_err;
1616 rqstp->rq_cred = rsci->cred;
1617 get_group_info(rsci->cred.cr_group_info);
1618 *authp = rpc_autherr_badcred;
1619 switch (gc->gc_svc) {
1620 case RPC_GSS_SVC_NONE:
1621 break;
1622 case RPC_GSS_SVC_INTEGRITY:
1623 /* placeholders for length and seq. number: */
1624 svc_putnl(resv, 0);
1625 svc_putnl(resv, 0);
1626 if (unwrap_integ_data(rqstp, &rqstp->rq_arg,
1627 gc->gc_seq, rsci->mechctx))
1628 goto garbage_args;
1629 rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE;
1630 break;
1631 case RPC_GSS_SVC_PRIVACY:
1632 /* placeholders for length and seq. number: */
1633 svc_putnl(resv, 0);
1634 svc_putnl(resv, 0);
1635 if (unwrap_priv_data(rqstp, &rqstp->rq_arg,
1636 gc->gc_seq, rsci->mechctx))
1637 goto garbage_args;
1638 rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE * 2;
1639 break;
1640 default:
1641 goto auth_err;
1642 }
1643 svcdata->rsci = rsci;
1644 cache_get(&rsci->h);
1645 rqstp->rq_cred.cr_flavor = gss_svc_to_pseudoflavor(
1646 rsci->mechctx->mech_type,
1647 GSS_C_QOP_DEFAULT,
1648 gc->gc_svc);
1649 ret = SVC_OK;
1650 trace_rpcgss_svc_authenticate(rqstp, gc);
1651 goto out;
1652 }
1653garbage_args:
1654 ret = SVC_GARBAGE;
1655 goto out;
1656auth_err:
1657 /* Restore write pointer to its original value: */
1658 xdr_ressize_check(rqstp, reject_stat);
1659 ret = SVC_DENIED;
1660 goto out;
1661complete:
1662 ret = SVC_COMPLETE;
1663 goto out;
1664drop:
1665 ret = SVC_CLOSE;
1666out:
1667 if (rsci)
1668 cache_put(&rsci->h, sn->rsc_cache);
1669 return ret;
1670}
1671
1672static __be32 *
1673svcauth_gss_prepare_to_wrap(struct xdr_buf *resbuf, struct gss_svc_data *gsd)
1674{
1675 __be32 *p;
1676 u32 verf_len;
1677
1678 p = gsd->verf_start;
1679 gsd->verf_start = NULL;
1680
1681 /* If the reply stat is nonzero, don't wrap: */
1682 if (*(p-1) != rpc_success)
1683 return NULL;
1684 /* Skip the verifier: */
1685 p += 1;
1686 verf_len = ntohl(*p++);
1687 p += XDR_QUADLEN(verf_len);
1688 /* move accept_stat to right place: */
1689 memcpy(p, p + 2, 4);
1690 /* Also don't wrap if the accept stat is nonzero: */
1691 if (*p != rpc_success) {
1692 resbuf->head[0].iov_len -= 2 * 4;
1693 return NULL;
1694 }
1695 p++;
1696 return p;
1697}
1698
1699static inline int
1700svcauth_gss_wrap_resp_integ(struct svc_rqst *rqstp)
1701{
1702 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1703 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1704 struct xdr_buf *resbuf = &rqstp->rq_res;
1705 struct xdr_buf integ_buf;
1706 struct xdr_netobj mic;
1707 struct kvec *resv;
1708 __be32 *p;
1709 int integ_offset, integ_len;
1710 int stat = -EINVAL;
1711
1712 p = svcauth_gss_prepare_to_wrap(resbuf, gsd);
1713 if (p == NULL)
1714 goto out;
1715 integ_offset = (u8 *)(p + 1) - (u8 *)resbuf->head[0].iov_base;
1716 integ_len = resbuf->len - integ_offset;
1717 if (integ_len & 3)
1718 goto out;
1719 *p++ = htonl(integ_len);
1720 *p++ = htonl(gc->gc_seq);
1721 if (xdr_buf_subsegment(resbuf, &integ_buf, integ_offset, integ_len)) {
1722 WARN_ON_ONCE(1);
1723 goto out_err;
1724 }
1725 if (resbuf->tail[0].iov_base == NULL) {
1726 if (resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1727 goto out_err;
1728 resbuf->tail[0].iov_base = resbuf->head[0].iov_base
1729 + resbuf->head[0].iov_len;
1730 resbuf->tail[0].iov_len = 0;
1731 }
1732 resv = &resbuf->tail[0];
1733 mic.data = (u8 *)resv->iov_base + resv->iov_len + 4;
1734 if (gss_get_mic(gsd->rsci->mechctx, &integ_buf, &mic))
1735 goto out_err;
1736 svc_putnl(resv, mic.len);
1737 memset(mic.data + mic.len, 0,
1738 round_up_to_quad(mic.len) - mic.len);
1739 resv->iov_len += XDR_QUADLEN(mic.len) << 2;
1740 /* not strictly required: */
1741 resbuf->len += XDR_QUADLEN(mic.len) << 2;
1742 if (resv->iov_len > PAGE_SIZE)
1743 goto out_err;
1744out:
1745 stat = 0;
1746out_err:
1747 return stat;
1748}
1749
1750static inline int
1751svcauth_gss_wrap_resp_priv(struct svc_rqst *rqstp)
1752{
1753 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1754 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1755 struct xdr_buf *resbuf = &rqstp->rq_res;
1756 struct page **inpages = NULL;
1757 __be32 *p, *len;
1758 int offset;
1759 int pad;
1760
1761 p = svcauth_gss_prepare_to_wrap(resbuf, gsd);
1762 if (p == NULL)
1763 return 0;
1764 len = p++;
1765 offset = (u8 *)p - (u8 *)resbuf->head[0].iov_base;
1766 *p++ = htonl(gc->gc_seq);
1767 inpages = resbuf->pages;
1768 /* XXX: Would be better to write some xdr helper functions for
1769 * nfs{2,3,4}xdr.c that place the data right, instead of copying: */
1770
1771 /*
1772 * If there is currently tail data, make sure there is
1773 * room for the head, tail, and 2 * RPC_MAX_AUTH_SIZE in
1774 * the page, and move the current tail data such that
1775 * there is RPC_MAX_AUTH_SIZE slack space available in
1776 * both the head and tail.
1777 */
1778 if (resbuf->tail[0].iov_base) {
1779 if (resbuf->tail[0].iov_base >=
1780 resbuf->head[0].iov_base + PAGE_SIZE)
1781 return -EINVAL;
1782 if (resbuf->tail[0].iov_base < resbuf->head[0].iov_base)
1783 return -EINVAL;
1784 if (resbuf->tail[0].iov_len + resbuf->head[0].iov_len
1785 + 2 * RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1786 return -ENOMEM;
1787 memmove(resbuf->tail[0].iov_base + RPC_MAX_AUTH_SIZE,
1788 resbuf->tail[0].iov_base,
1789 resbuf->tail[0].iov_len);
1790 resbuf->tail[0].iov_base += RPC_MAX_AUTH_SIZE;
1791 }
1792 /*
1793 * If there is no current tail data, make sure there is
1794 * room for the head data, and 2 * RPC_MAX_AUTH_SIZE in the
1795 * allotted page, and set up tail information such that there
1796 * is RPC_MAX_AUTH_SIZE slack space available in both the
1797 * head and tail.
1798 */
1799 if (resbuf->tail[0].iov_base == NULL) {
1800 if (resbuf->head[0].iov_len + 2*RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1801 return -ENOMEM;
1802 resbuf->tail[0].iov_base = resbuf->head[0].iov_base
1803 + resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE;
1804 resbuf->tail[0].iov_len = 0;
1805 }
1806 if (gss_wrap(gsd->rsci->mechctx, offset, resbuf, inpages))
1807 return -ENOMEM;
1808 *len = htonl(resbuf->len - offset);
1809 pad = 3 - ((resbuf->len - offset - 1)&3);
1810 p = (__be32 *)(resbuf->tail[0].iov_base + resbuf->tail[0].iov_len);
1811 memset(p, 0, pad);
1812 resbuf->tail[0].iov_len += pad;
1813 resbuf->len += pad;
1814 return 0;
1815}
1816
1817static int
1818svcauth_gss_release(struct svc_rqst *rqstp)
1819{
1820 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1821 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1822 struct xdr_buf *resbuf = &rqstp->rq_res;
1823 int stat = -EINVAL;
1824 struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id);
1825
1826 if (gc->gc_proc != RPC_GSS_PROC_DATA)
1827 goto out;
1828 /* Release can be called twice, but we only wrap once. */
1829 if (gsd->verf_start == NULL)
1830 goto out;
1831 /* normally not set till svc_send, but we need it here: */
1832 /* XXX: what for? Do we mess it up the moment we call svc_putu32
1833 * or whatever? */
1834 resbuf->len = total_buf_len(resbuf);
1835 switch (gc->gc_svc) {
1836 case RPC_GSS_SVC_NONE:
1837 break;
1838 case RPC_GSS_SVC_INTEGRITY:
1839 stat = svcauth_gss_wrap_resp_integ(rqstp);
1840 if (stat)
1841 goto out_err;
1842 break;
1843 case RPC_GSS_SVC_PRIVACY:
1844 stat = svcauth_gss_wrap_resp_priv(rqstp);
1845 if (stat)
1846 goto out_err;
1847 break;
1848 /*
1849 * For any other gc_svc value, svcauth_gss_accept() already set
1850 * the auth_error appropriately; just fall through:
1851 */
1852 }
1853
1854out:
1855 stat = 0;
1856out_err:
1857 if (rqstp->rq_client)
1858 auth_domain_put(rqstp->rq_client);
1859 rqstp->rq_client = NULL;
1860 if (rqstp->rq_gssclient)
1861 auth_domain_put(rqstp->rq_gssclient);
1862 rqstp->rq_gssclient = NULL;
1863 if (rqstp->rq_cred.cr_group_info)
1864 put_group_info(rqstp->rq_cred.cr_group_info);
1865 rqstp->rq_cred.cr_group_info = NULL;
1866 if (gsd->rsci)
1867 cache_put(&gsd->rsci->h, sn->rsc_cache);
1868 gsd->rsci = NULL;
1869
1870 return stat;
1871}
1872
1873static void
1874svcauth_gss_domain_release_rcu(struct rcu_head *head)
1875{
1876 struct auth_domain *dom = container_of(head, struct auth_domain, rcu_head);
1877 struct gss_domain *gd = container_of(dom, struct gss_domain, h);
1878
1879 kfree(dom->name);
1880 kfree(gd);
1881}
1882
1883static void
1884svcauth_gss_domain_release(struct auth_domain *dom)
1885{
1886 call_rcu(&dom->rcu_head, svcauth_gss_domain_release_rcu);
1887}
1888
1889static struct auth_ops svcauthops_gss = {
1890 .name = "rpcsec_gss",
1891 .owner = THIS_MODULE,
1892 .flavour = RPC_AUTH_GSS,
1893 .accept = svcauth_gss_accept,
1894 .release = svcauth_gss_release,
1895 .domain_release = svcauth_gss_domain_release,
1896 .set_client = svcauth_gss_set_client,
1897};
1898
1899static int rsi_cache_create_net(struct net *net)
1900{
1901 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1902 struct cache_detail *cd;
1903 int err;
1904
1905 cd = cache_create_net(&rsi_cache_template, net);
1906 if (IS_ERR(cd))
1907 return PTR_ERR(cd);
1908 err = cache_register_net(cd, net);
1909 if (err) {
1910 cache_destroy_net(cd, net);
1911 return err;
1912 }
1913 sn->rsi_cache = cd;
1914 return 0;
1915}
1916
1917static void rsi_cache_destroy_net(struct net *net)
1918{
1919 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1920 struct cache_detail *cd = sn->rsi_cache;
1921
1922 sn->rsi_cache = NULL;
1923 cache_purge(cd);
1924 cache_unregister_net(cd, net);
1925 cache_destroy_net(cd, net);
1926}
1927
1928static int rsc_cache_create_net(struct net *net)
1929{
1930 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1931 struct cache_detail *cd;
1932 int err;
1933
1934 cd = cache_create_net(&rsc_cache_template, net);
1935 if (IS_ERR(cd))
1936 return PTR_ERR(cd);
1937 err = cache_register_net(cd, net);
1938 if (err) {
1939 cache_destroy_net(cd, net);
1940 return err;
1941 }
1942 sn->rsc_cache = cd;
1943 return 0;
1944}
1945
1946static void rsc_cache_destroy_net(struct net *net)
1947{
1948 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1949 struct cache_detail *cd = sn->rsc_cache;
1950
1951 sn->rsc_cache = NULL;
1952 cache_purge(cd);
1953 cache_unregister_net(cd, net);
1954 cache_destroy_net(cd, net);
1955}
1956
1957int
1958gss_svc_init_net(struct net *net)
1959{
1960 int rv;
1961
1962 rv = rsc_cache_create_net(net);
1963 if (rv)
1964 return rv;
1965 rv = rsi_cache_create_net(net);
1966 if (rv)
1967 goto out1;
1968 rv = create_use_gss_proxy_proc_entry(net);
1969 if (rv)
1970 goto out2;
1971 return 0;
1972out2:
1973 destroy_use_gss_proxy_proc_entry(net);
1974out1:
1975 rsc_cache_destroy_net(net);
1976 return rv;
1977}
1978
1979void
1980gss_svc_shutdown_net(struct net *net)
1981{
1982 destroy_use_gss_proxy_proc_entry(net);
1983 rsi_cache_destroy_net(net);
1984 rsc_cache_destroy_net(net);
1985}
1986
1987int
1988gss_svc_init(void)
1989{
1990 return svc_auth_register(RPC_AUTH_GSS, &svcauthops_gss);
1991}
1992
1993void
1994gss_svc_shutdown(void)
1995{
1996 svc_auth_unregister(RPC_AUTH_GSS);
1997}
1/*
2 * Neil Brown <neilb@cse.unsw.edu.au>
3 * J. Bruce Fields <bfields@umich.edu>
4 * Andy Adamson <andros@umich.edu>
5 * Dug Song <dugsong@monkey.org>
6 *
7 * RPCSEC_GSS server authentication.
8 * This implements RPCSEC_GSS as defined in rfc2203 (rpcsec_gss) and rfc2078
9 * (gssapi)
10 *
11 * The RPCSEC_GSS involves three stages:
12 * 1/ context creation
13 * 2/ data exchange
14 * 3/ context destruction
15 *
16 * Context creation is handled largely by upcalls to user-space.
17 * In particular, GSS_Accept_sec_context is handled by an upcall
18 * Data exchange is handled entirely within the kernel
19 * In particular, GSS_GetMIC, GSS_VerifyMIC, GSS_Seal, GSS_Unseal are in-kernel.
20 * Context destruction is handled in-kernel
21 * GSS_Delete_sec_context is in-kernel
22 *
23 * Context creation is initiated by a RPCSEC_GSS_INIT request arriving.
24 * The context handle and gss_token are used as a key into the rpcsec_init cache.
25 * The content of this cache includes some of the outputs of GSS_Accept_sec_context,
26 * being major_status, minor_status, context_handle, reply_token.
27 * These are sent back to the client.
28 * Sequence window management is handled by the kernel. The window size if currently
29 * a compile time constant.
30 *
31 * When user-space is happy that a context is established, it places an entry
32 * in the rpcsec_context cache. The key for this cache is the context_handle.
33 * The content includes:
34 * uid/gidlist - for determining access rights
35 * mechanism type
36 * mechanism specific information, such as a key
37 *
38 */
39
40#include <linux/slab.h>
41#include <linux/types.h>
42#include <linux/module.h>
43#include <linux/pagemap.h>
44#include <linux/user_namespace.h>
45
46#include <linux/sunrpc/auth_gss.h>
47#include <linux/sunrpc/gss_err.h>
48#include <linux/sunrpc/svcauth.h>
49#include <linux/sunrpc/svcauth_gss.h>
50#include <linux/sunrpc/cache.h>
51#include "gss_rpc_upcall.h"
52
53
54#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
55# define RPCDBG_FACILITY RPCDBG_AUTH
56#endif
57
58/* The rpcsec_init cache is used for mapping RPCSEC_GSS_{,CONT_}INIT requests
59 * into replies.
60 *
61 * Key is context handle (\x if empty) and gss_token.
62 * Content is major_status minor_status (integers) context_handle, reply_token.
63 *
64 */
65
66static int netobj_equal(struct xdr_netobj *a, struct xdr_netobj *b)
67{
68 return a->len == b->len && 0 == memcmp(a->data, b->data, a->len);
69}
70
71#define RSI_HASHBITS 6
72#define RSI_HASHMAX (1<<RSI_HASHBITS)
73
74struct rsi {
75 struct cache_head h;
76 struct xdr_netobj in_handle, in_token;
77 struct xdr_netobj out_handle, out_token;
78 int major_status, minor_status;
79};
80
81static struct rsi *rsi_update(struct cache_detail *cd, struct rsi *new, struct rsi *old);
82static struct rsi *rsi_lookup(struct cache_detail *cd, struct rsi *item);
83
84static void rsi_free(struct rsi *rsii)
85{
86 kfree(rsii->in_handle.data);
87 kfree(rsii->in_token.data);
88 kfree(rsii->out_handle.data);
89 kfree(rsii->out_token.data);
90}
91
92static void rsi_put(struct kref *ref)
93{
94 struct rsi *rsii = container_of(ref, struct rsi, h.ref);
95 rsi_free(rsii);
96 kfree(rsii);
97}
98
99static inline int rsi_hash(struct rsi *item)
100{
101 return hash_mem(item->in_handle.data, item->in_handle.len, RSI_HASHBITS)
102 ^ hash_mem(item->in_token.data, item->in_token.len, RSI_HASHBITS);
103}
104
105static int rsi_match(struct cache_head *a, struct cache_head *b)
106{
107 struct rsi *item = container_of(a, struct rsi, h);
108 struct rsi *tmp = container_of(b, struct rsi, h);
109 return netobj_equal(&item->in_handle, &tmp->in_handle) &&
110 netobj_equal(&item->in_token, &tmp->in_token);
111}
112
113static int dup_to_netobj(struct xdr_netobj *dst, char *src, int len)
114{
115 dst->len = len;
116 dst->data = (len ? kmemdup(src, len, GFP_KERNEL) : NULL);
117 if (len && !dst->data)
118 return -ENOMEM;
119 return 0;
120}
121
122static inline int dup_netobj(struct xdr_netobj *dst, struct xdr_netobj *src)
123{
124 return dup_to_netobj(dst, src->data, src->len);
125}
126
127static void rsi_init(struct cache_head *cnew, struct cache_head *citem)
128{
129 struct rsi *new = container_of(cnew, struct rsi, h);
130 struct rsi *item = container_of(citem, struct rsi, h);
131
132 new->out_handle.data = NULL;
133 new->out_handle.len = 0;
134 new->out_token.data = NULL;
135 new->out_token.len = 0;
136 new->in_handle.len = item->in_handle.len;
137 item->in_handle.len = 0;
138 new->in_token.len = item->in_token.len;
139 item->in_token.len = 0;
140 new->in_handle.data = item->in_handle.data;
141 item->in_handle.data = NULL;
142 new->in_token.data = item->in_token.data;
143 item->in_token.data = NULL;
144}
145
146static void update_rsi(struct cache_head *cnew, struct cache_head *citem)
147{
148 struct rsi *new = container_of(cnew, struct rsi, h);
149 struct rsi *item = container_of(citem, struct rsi, h);
150
151 BUG_ON(new->out_handle.data || new->out_token.data);
152 new->out_handle.len = item->out_handle.len;
153 item->out_handle.len = 0;
154 new->out_token.len = item->out_token.len;
155 item->out_token.len = 0;
156 new->out_handle.data = item->out_handle.data;
157 item->out_handle.data = NULL;
158 new->out_token.data = item->out_token.data;
159 item->out_token.data = NULL;
160
161 new->major_status = item->major_status;
162 new->minor_status = item->minor_status;
163}
164
165static struct cache_head *rsi_alloc(void)
166{
167 struct rsi *rsii = kmalloc(sizeof(*rsii), GFP_KERNEL);
168 if (rsii)
169 return &rsii->h;
170 else
171 return NULL;
172}
173
174static void rsi_request(struct cache_detail *cd,
175 struct cache_head *h,
176 char **bpp, int *blen)
177{
178 struct rsi *rsii = container_of(h, struct rsi, h);
179
180 qword_addhex(bpp, blen, rsii->in_handle.data, rsii->in_handle.len);
181 qword_addhex(bpp, blen, rsii->in_token.data, rsii->in_token.len);
182 (*bpp)[-1] = '\n';
183}
184
185static int rsi_parse(struct cache_detail *cd,
186 char *mesg, int mlen)
187{
188 /* context token expiry major minor context token */
189 char *buf = mesg;
190 char *ep;
191 int len;
192 struct rsi rsii, *rsip = NULL;
193 time_t expiry;
194 int status = -EINVAL;
195
196 memset(&rsii, 0, sizeof(rsii));
197 /* handle */
198 len = qword_get(&mesg, buf, mlen);
199 if (len < 0)
200 goto out;
201 status = -ENOMEM;
202 if (dup_to_netobj(&rsii.in_handle, buf, len))
203 goto out;
204
205 /* token */
206 len = qword_get(&mesg, buf, mlen);
207 status = -EINVAL;
208 if (len < 0)
209 goto out;
210 status = -ENOMEM;
211 if (dup_to_netobj(&rsii.in_token, buf, len))
212 goto out;
213
214 rsip = rsi_lookup(cd, &rsii);
215 if (!rsip)
216 goto out;
217
218 rsii.h.flags = 0;
219 /* expiry */
220 expiry = get_expiry(&mesg);
221 status = -EINVAL;
222 if (expiry == 0)
223 goto out;
224
225 /* major/minor */
226 len = qword_get(&mesg, buf, mlen);
227 if (len <= 0)
228 goto out;
229 rsii.major_status = simple_strtoul(buf, &ep, 10);
230 if (*ep)
231 goto out;
232 len = qword_get(&mesg, buf, mlen);
233 if (len <= 0)
234 goto out;
235 rsii.minor_status = simple_strtoul(buf, &ep, 10);
236 if (*ep)
237 goto out;
238
239 /* out_handle */
240 len = qword_get(&mesg, buf, mlen);
241 if (len < 0)
242 goto out;
243 status = -ENOMEM;
244 if (dup_to_netobj(&rsii.out_handle, buf, len))
245 goto out;
246
247 /* out_token */
248 len = qword_get(&mesg, buf, mlen);
249 status = -EINVAL;
250 if (len < 0)
251 goto out;
252 status = -ENOMEM;
253 if (dup_to_netobj(&rsii.out_token, buf, len))
254 goto out;
255 rsii.h.expiry_time = expiry;
256 rsip = rsi_update(cd, &rsii, rsip);
257 status = 0;
258out:
259 rsi_free(&rsii);
260 if (rsip)
261 cache_put(&rsip->h, cd);
262 else
263 status = -ENOMEM;
264 return status;
265}
266
267static const struct cache_detail rsi_cache_template = {
268 .owner = THIS_MODULE,
269 .hash_size = RSI_HASHMAX,
270 .name = "auth.rpcsec.init",
271 .cache_put = rsi_put,
272 .cache_request = rsi_request,
273 .cache_parse = rsi_parse,
274 .match = rsi_match,
275 .init = rsi_init,
276 .update = update_rsi,
277 .alloc = rsi_alloc,
278};
279
280static struct rsi *rsi_lookup(struct cache_detail *cd, struct rsi *item)
281{
282 struct cache_head *ch;
283 int hash = rsi_hash(item);
284
285 ch = sunrpc_cache_lookup(cd, &item->h, hash);
286 if (ch)
287 return container_of(ch, struct rsi, h);
288 else
289 return NULL;
290}
291
292static struct rsi *rsi_update(struct cache_detail *cd, struct rsi *new, struct rsi *old)
293{
294 struct cache_head *ch;
295 int hash = rsi_hash(new);
296
297 ch = sunrpc_cache_update(cd, &new->h,
298 &old->h, hash);
299 if (ch)
300 return container_of(ch, struct rsi, h);
301 else
302 return NULL;
303}
304
305
306/*
307 * The rpcsec_context cache is used to store a context that is
308 * used in data exchange.
309 * The key is a context handle. The content is:
310 * uid, gidlist, mechanism, service-set, mech-specific-data
311 */
312
313#define RSC_HASHBITS 10
314#define RSC_HASHMAX (1<<RSC_HASHBITS)
315
316#define GSS_SEQ_WIN 128
317
318struct gss_svc_seq_data {
319 /* highest seq number seen so far: */
320 int sd_max;
321 /* for i such that sd_max-GSS_SEQ_WIN < i <= sd_max, the i-th bit of
322 * sd_win is nonzero iff sequence number i has been seen already: */
323 unsigned long sd_win[GSS_SEQ_WIN/BITS_PER_LONG];
324 spinlock_t sd_lock;
325};
326
327struct rsc {
328 struct cache_head h;
329 struct xdr_netobj handle;
330 struct svc_cred cred;
331 struct gss_svc_seq_data seqdata;
332 struct gss_ctx *mechctx;
333};
334
335static struct rsc *rsc_update(struct cache_detail *cd, struct rsc *new, struct rsc *old);
336static struct rsc *rsc_lookup(struct cache_detail *cd, struct rsc *item);
337
338static void rsc_free(struct rsc *rsci)
339{
340 kfree(rsci->handle.data);
341 if (rsci->mechctx)
342 gss_delete_sec_context(&rsci->mechctx);
343 free_svc_cred(&rsci->cred);
344}
345
346static void rsc_put(struct kref *ref)
347{
348 struct rsc *rsci = container_of(ref, struct rsc, h.ref);
349
350 rsc_free(rsci);
351 kfree(rsci);
352}
353
354static inline int
355rsc_hash(struct rsc *rsci)
356{
357 return hash_mem(rsci->handle.data, rsci->handle.len, RSC_HASHBITS);
358}
359
360static int
361rsc_match(struct cache_head *a, struct cache_head *b)
362{
363 struct rsc *new = container_of(a, struct rsc, h);
364 struct rsc *tmp = container_of(b, struct rsc, h);
365
366 return netobj_equal(&new->handle, &tmp->handle);
367}
368
369static void
370rsc_init(struct cache_head *cnew, struct cache_head *ctmp)
371{
372 struct rsc *new = container_of(cnew, struct rsc, h);
373 struct rsc *tmp = container_of(ctmp, struct rsc, h);
374
375 new->handle.len = tmp->handle.len;
376 tmp->handle.len = 0;
377 new->handle.data = tmp->handle.data;
378 tmp->handle.data = NULL;
379 new->mechctx = NULL;
380 init_svc_cred(&new->cred);
381}
382
383static void
384update_rsc(struct cache_head *cnew, struct cache_head *ctmp)
385{
386 struct rsc *new = container_of(cnew, struct rsc, h);
387 struct rsc *tmp = container_of(ctmp, struct rsc, h);
388
389 new->mechctx = tmp->mechctx;
390 tmp->mechctx = NULL;
391 memset(&new->seqdata, 0, sizeof(new->seqdata));
392 spin_lock_init(&new->seqdata.sd_lock);
393 new->cred = tmp->cred;
394 init_svc_cred(&tmp->cred);
395}
396
397static struct cache_head *
398rsc_alloc(void)
399{
400 struct rsc *rsci = kmalloc(sizeof(*rsci), GFP_KERNEL);
401 if (rsci)
402 return &rsci->h;
403 else
404 return NULL;
405}
406
407static int rsc_parse(struct cache_detail *cd,
408 char *mesg, int mlen)
409{
410 /* contexthandle expiry [ uid gid N <n gids> mechname ...mechdata... ] */
411 char *buf = mesg;
412 int id;
413 int len, rv;
414 struct rsc rsci, *rscp = NULL;
415 time_t expiry;
416 int status = -EINVAL;
417 struct gss_api_mech *gm = NULL;
418
419 memset(&rsci, 0, sizeof(rsci));
420 /* context handle */
421 len = qword_get(&mesg, buf, mlen);
422 if (len < 0) goto out;
423 status = -ENOMEM;
424 if (dup_to_netobj(&rsci.handle, buf, len))
425 goto out;
426
427 rsci.h.flags = 0;
428 /* expiry */
429 expiry = get_expiry(&mesg);
430 status = -EINVAL;
431 if (expiry == 0)
432 goto out;
433
434 rscp = rsc_lookup(cd, &rsci);
435 if (!rscp)
436 goto out;
437
438 /* uid, or NEGATIVE */
439 rv = get_int(&mesg, &id);
440 if (rv == -EINVAL)
441 goto out;
442 if (rv == -ENOENT)
443 set_bit(CACHE_NEGATIVE, &rsci.h.flags);
444 else {
445 int N, i;
446
447 /*
448 * NOTE: we skip uid_valid()/gid_valid() checks here:
449 * instead, * -1 id's are later mapped to the
450 * (export-specific) anonymous id by nfsd_setuser.
451 *
452 * (But supplementary gid's get no such special
453 * treatment so are checked for validity here.)
454 */
455 /* uid */
456 rsci.cred.cr_uid = make_kuid(&init_user_ns, id);
457
458 /* gid */
459 if (get_int(&mesg, &id))
460 goto out;
461 rsci.cred.cr_gid = make_kgid(&init_user_ns, id);
462
463 /* number of additional gid's */
464 if (get_int(&mesg, &N))
465 goto out;
466 if (N < 0 || N > NGROUPS_MAX)
467 goto out;
468 status = -ENOMEM;
469 rsci.cred.cr_group_info = groups_alloc(N);
470 if (rsci.cred.cr_group_info == NULL)
471 goto out;
472
473 /* gid's */
474 status = -EINVAL;
475 for (i=0; i<N; i++) {
476 kgid_t kgid;
477 if (get_int(&mesg, &id))
478 goto out;
479 kgid = make_kgid(&init_user_ns, id);
480 if (!gid_valid(kgid))
481 goto out;
482 rsci.cred.cr_group_info->gid[i] = kgid;
483 }
484 groups_sort(rsci.cred.cr_group_info);
485
486 /* mech name */
487 len = qword_get(&mesg, buf, mlen);
488 if (len < 0)
489 goto out;
490 gm = rsci.cred.cr_gss_mech = gss_mech_get_by_name(buf);
491 status = -EOPNOTSUPP;
492 if (!gm)
493 goto out;
494
495 status = -EINVAL;
496 /* mech-specific data: */
497 len = qword_get(&mesg, buf, mlen);
498 if (len < 0)
499 goto out;
500 status = gss_import_sec_context(buf, len, gm, &rsci.mechctx,
501 NULL, GFP_KERNEL);
502 if (status)
503 goto out;
504
505 /* get client name */
506 len = qword_get(&mesg, buf, mlen);
507 if (len > 0) {
508 rsci.cred.cr_principal = kstrdup(buf, GFP_KERNEL);
509 if (!rsci.cred.cr_principal) {
510 status = -ENOMEM;
511 goto out;
512 }
513 }
514
515 }
516 rsci.h.expiry_time = expiry;
517 rscp = rsc_update(cd, &rsci, rscp);
518 status = 0;
519out:
520 rsc_free(&rsci);
521 if (rscp)
522 cache_put(&rscp->h, cd);
523 else
524 status = -ENOMEM;
525 return status;
526}
527
528static const struct cache_detail rsc_cache_template = {
529 .owner = THIS_MODULE,
530 .hash_size = RSC_HASHMAX,
531 .name = "auth.rpcsec.context",
532 .cache_put = rsc_put,
533 .cache_parse = rsc_parse,
534 .match = rsc_match,
535 .init = rsc_init,
536 .update = update_rsc,
537 .alloc = rsc_alloc,
538};
539
540static struct rsc *rsc_lookup(struct cache_detail *cd, struct rsc *item)
541{
542 struct cache_head *ch;
543 int hash = rsc_hash(item);
544
545 ch = sunrpc_cache_lookup(cd, &item->h, hash);
546 if (ch)
547 return container_of(ch, struct rsc, h);
548 else
549 return NULL;
550}
551
552static struct rsc *rsc_update(struct cache_detail *cd, struct rsc *new, struct rsc *old)
553{
554 struct cache_head *ch;
555 int hash = rsc_hash(new);
556
557 ch = sunrpc_cache_update(cd, &new->h,
558 &old->h, hash);
559 if (ch)
560 return container_of(ch, struct rsc, h);
561 else
562 return NULL;
563}
564
565
566static struct rsc *
567gss_svc_searchbyctx(struct cache_detail *cd, struct xdr_netobj *handle)
568{
569 struct rsc rsci;
570 struct rsc *found;
571
572 memset(&rsci, 0, sizeof(rsci));
573 if (dup_to_netobj(&rsci.handle, handle->data, handle->len))
574 return NULL;
575 found = rsc_lookup(cd, &rsci);
576 rsc_free(&rsci);
577 if (!found)
578 return NULL;
579 if (cache_check(cd, &found->h, NULL))
580 return NULL;
581 return found;
582}
583
584/* Implements sequence number algorithm as specified in RFC 2203. */
585static int
586gss_check_seq_num(struct rsc *rsci, int seq_num)
587{
588 struct gss_svc_seq_data *sd = &rsci->seqdata;
589
590 spin_lock(&sd->sd_lock);
591 if (seq_num > sd->sd_max) {
592 if (seq_num >= sd->sd_max + GSS_SEQ_WIN) {
593 memset(sd->sd_win,0,sizeof(sd->sd_win));
594 sd->sd_max = seq_num;
595 } else while (sd->sd_max < seq_num) {
596 sd->sd_max++;
597 __clear_bit(sd->sd_max % GSS_SEQ_WIN, sd->sd_win);
598 }
599 __set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win);
600 goto ok;
601 } else if (seq_num <= sd->sd_max - GSS_SEQ_WIN) {
602 goto drop;
603 }
604 /* sd_max - GSS_SEQ_WIN < seq_num <= sd_max */
605 if (__test_and_set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win))
606 goto drop;
607ok:
608 spin_unlock(&sd->sd_lock);
609 return 1;
610drop:
611 spin_unlock(&sd->sd_lock);
612 return 0;
613}
614
615static inline u32 round_up_to_quad(u32 i)
616{
617 return (i + 3 ) & ~3;
618}
619
620static inline int
621svc_safe_getnetobj(struct kvec *argv, struct xdr_netobj *o)
622{
623 int l;
624
625 if (argv->iov_len < 4)
626 return -1;
627 o->len = svc_getnl(argv);
628 l = round_up_to_quad(o->len);
629 if (argv->iov_len < l)
630 return -1;
631 o->data = argv->iov_base;
632 argv->iov_base += l;
633 argv->iov_len -= l;
634 return 0;
635}
636
637static inline int
638svc_safe_putnetobj(struct kvec *resv, struct xdr_netobj *o)
639{
640 u8 *p;
641
642 if (resv->iov_len + 4 > PAGE_SIZE)
643 return -1;
644 svc_putnl(resv, o->len);
645 p = resv->iov_base + resv->iov_len;
646 resv->iov_len += round_up_to_quad(o->len);
647 if (resv->iov_len > PAGE_SIZE)
648 return -1;
649 memcpy(p, o->data, o->len);
650 memset(p + o->len, 0, round_up_to_quad(o->len) - o->len);
651 return 0;
652}
653
654/*
655 * Verify the checksum on the header and return SVC_OK on success.
656 * Otherwise, return SVC_DROP (in the case of a bad sequence number)
657 * or return SVC_DENIED and indicate error in authp.
658 */
659static int
660gss_verify_header(struct svc_rqst *rqstp, struct rsc *rsci,
661 __be32 *rpcstart, struct rpc_gss_wire_cred *gc, __be32 *authp)
662{
663 struct gss_ctx *ctx_id = rsci->mechctx;
664 struct xdr_buf rpchdr;
665 struct xdr_netobj checksum;
666 u32 flavor = 0;
667 struct kvec *argv = &rqstp->rq_arg.head[0];
668 struct kvec iov;
669
670 /* data to compute the checksum over: */
671 iov.iov_base = rpcstart;
672 iov.iov_len = (u8 *)argv->iov_base - (u8 *)rpcstart;
673 xdr_buf_from_iov(&iov, &rpchdr);
674
675 *authp = rpc_autherr_badverf;
676 if (argv->iov_len < 4)
677 return SVC_DENIED;
678 flavor = svc_getnl(argv);
679 if (flavor != RPC_AUTH_GSS)
680 return SVC_DENIED;
681 if (svc_safe_getnetobj(argv, &checksum))
682 return SVC_DENIED;
683
684 if (rqstp->rq_deferred) /* skip verification of revisited request */
685 return SVC_OK;
686 if (gss_verify_mic(ctx_id, &rpchdr, &checksum) != GSS_S_COMPLETE) {
687 *authp = rpcsec_gsserr_credproblem;
688 return SVC_DENIED;
689 }
690
691 if (gc->gc_seq > MAXSEQ) {
692 dprintk("RPC: svcauth_gss: discarding request with "
693 "large sequence number %d\n", gc->gc_seq);
694 *authp = rpcsec_gsserr_ctxproblem;
695 return SVC_DENIED;
696 }
697 if (!gss_check_seq_num(rsci, gc->gc_seq)) {
698 dprintk("RPC: svcauth_gss: discarding request with "
699 "old sequence number %d\n", gc->gc_seq);
700 return SVC_DROP;
701 }
702 return SVC_OK;
703}
704
705static int
706gss_write_null_verf(struct svc_rqst *rqstp)
707{
708 __be32 *p;
709
710 svc_putnl(rqstp->rq_res.head, RPC_AUTH_NULL);
711 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len;
712 /* don't really need to check if head->iov_len > PAGE_SIZE ... */
713 *p++ = 0;
714 if (!xdr_ressize_check(rqstp, p))
715 return -1;
716 return 0;
717}
718
719static int
720gss_write_verf(struct svc_rqst *rqstp, struct gss_ctx *ctx_id, u32 seq)
721{
722 __be32 *xdr_seq;
723 u32 maj_stat;
724 struct xdr_buf verf_data;
725 struct xdr_netobj mic;
726 __be32 *p;
727 struct kvec iov;
728 int err = -1;
729
730 svc_putnl(rqstp->rq_res.head, RPC_AUTH_GSS);
731 xdr_seq = kmalloc(4, GFP_KERNEL);
732 if (!xdr_seq)
733 return -1;
734 *xdr_seq = htonl(seq);
735
736 iov.iov_base = xdr_seq;
737 iov.iov_len = 4;
738 xdr_buf_from_iov(&iov, &verf_data);
739 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len;
740 mic.data = (u8 *)(p + 1);
741 maj_stat = gss_get_mic(ctx_id, &verf_data, &mic);
742 if (maj_stat != GSS_S_COMPLETE)
743 goto out;
744 *p++ = htonl(mic.len);
745 memset((u8 *)p + mic.len, 0, round_up_to_quad(mic.len) - mic.len);
746 p += XDR_QUADLEN(mic.len);
747 if (!xdr_ressize_check(rqstp, p))
748 goto out;
749 err = 0;
750out:
751 kfree(xdr_seq);
752 return err;
753}
754
755struct gss_domain {
756 struct auth_domain h;
757 u32 pseudoflavor;
758};
759
760static struct auth_domain *
761find_gss_auth_domain(struct gss_ctx *ctx, u32 svc)
762{
763 char *name;
764
765 name = gss_service_to_auth_domain_name(ctx->mech_type, svc);
766 if (!name)
767 return NULL;
768 return auth_domain_find(name);
769}
770
771static struct auth_ops svcauthops_gss;
772
773u32 svcauth_gss_flavor(struct auth_domain *dom)
774{
775 struct gss_domain *gd = container_of(dom, struct gss_domain, h);
776
777 return gd->pseudoflavor;
778}
779
780EXPORT_SYMBOL_GPL(svcauth_gss_flavor);
781
782int
783svcauth_gss_register_pseudoflavor(u32 pseudoflavor, char * name)
784{
785 struct gss_domain *new;
786 struct auth_domain *test;
787 int stat = -ENOMEM;
788
789 new = kmalloc(sizeof(*new), GFP_KERNEL);
790 if (!new)
791 goto out;
792 kref_init(&new->h.ref);
793 new->h.name = kstrdup(name, GFP_KERNEL);
794 if (!new->h.name)
795 goto out_free_dom;
796 new->h.flavour = &svcauthops_gss;
797 new->pseudoflavor = pseudoflavor;
798
799 stat = 0;
800 test = auth_domain_lookup(name, &new->h);
801 if (test != &new->h) { /* Duplicate registration */
802 auth_domain_put(test);
803 kfree(new->h.name);
804 goto out_free_dom;
805 }
806 return 0;
807
808out_free_dom:
809 kfree(new);
810out:
811 return stat;
812}
813
814EXPORT_SYMBOL_GPL(svcauth_gss_register_pseudoflavor);
815
816static inline int
817read_u32_from_xdr_buf(struct xdr_buf *buf, int base, u32 *obj)
818{
819 __be32 raw;
820 int status;
821
822 status = read_bytes_from_xdr_buf(buf, base, &raw, sizeof(*obj));
823 if (status)
824 return status;
825 *obj = ntohl(raw);
826 return 0;
827}
828
829/* It would be nice if this bit of code could be shared with the client.
830 * Obstacles:
831 * The client shouldn't malloc(), would have to pass in own memory.
832 * The server uses base of head iovec as read pointer, while the
833 * client uses separate pointer. */
834static int
835unwrap_integ_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx)
836{
837 int stat = -EINVAL;
838 u32 integ_len, maj_stat;
839 struct xdr_netobj mic;
840 struct xdr_buf integ_buf;
841
842 /* NFS READ normally uses splice to send data in-place. However
843 * the data in cache can change after the reply's MIC is computed
844 * but before the RPC reply is sent. To prevent the client from
845 * rejecting the server-computed MIC in this somewhat rare case,
846 * do not use splice with the GSS integrity service.
847 */
848 clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
849
850 /* Did we already verify the signature on the original pass through? */
851 if (rqstp->rq_deferred)
852 return 0;
853
854 integ_len = svc_getnl(&buf->head[0]);
855 if (integ_len & 3)
856 return stat;
857 if (integ_len > buf->len)
858 return stat;
859 if (xdr_buf_subsegment(buf, &integ_buf, 0, integ_len)) {
860 WARN_ON_ONCE(1);
861 return stat;
862 }
863 /* copy out mic... */
864 if (read_u32_from_xdr_buf(buf, integ_len, &mic.len))
865 return stat;
866 if (mic.len > RPC_MAX_AUTH_SIZE)
867 return stat;
868 mic.data = kmalloc(mic.len, GFP_KERNEL);
869 if (!mic.data)
870 return stat;
871 if (read_bytes_from_xdr_buf(buf, integ_len + 4, mic.data, mic.len))
872 goto out;
873 maj_stat = gss_verify_mic(ctx, &integ_buf, &mic);
874 if (maj_stat != GSS_S_COMPLETE)
875 goto out;
876 if (svc_getnl(&buf->head[0]) != seq)
877 goto out;
878 /* trim off the mic and padding at the end before returning */
879 xdr_buf_trim(buf, round_up_to_quad(mic.len) + 4);
880 stat = 0;
881out:
882 kfree(mic.data);
883 return stat;
884}
885
886static inline int
887total_buf_len(struct xdr_buf *buf)
888{
889 return buf->head[0].iov_len + buf->page_len + buf->tail[0].iov_len;
890}
891
892static void
893fix_priv_head(struct xdr_buf *buf, int pad)
894{
895 if (buf->page_len == 0) {
896 /* We need to adjust head and buf->len in tandem in this
897 * case to make svc_defer() work--it finds the original
898 * buffer start using buf->len - buf->head[0].iov_len. */
899 buf->head[0].iov_len -= pad;
900 }
901}
902
903static int
904unwrap_priv_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx)
905{
906 u32 priv_len, maj_stat;
907 int pad, saved_len, remaining_len, offset;
908
909 clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
910
911 priv_len = svc_getnl(&buf->head[0]);
912 if (rqstp->rq_deferred) {
913 /* Already decrypted last time through! The sequence number
914 * check at out_seq is unnecessary but harmless: */
915 goto out_seq;
916 }
917 /* buf->len is the number of bytes from the original start of the
918 * request to the end, where head[0].iov_len is just the bytes
919 * not yet read from the head, so these two values are different: */
920 remaining_len = total_buf_len(buf);
921 if (priv_len > remaining_len)
922 return -EINVAL;
923 pad = remaining_len - priv_len;
924 buf->len -= pad;
925 fix_priv_head(buf, pad);
926
927 /* Maybe it would be better to give gss_unwrap a length parameter: */
928 saved_len = buf->len;
929 buf->len = priv_len;
930 maj_stat = gss_unwrap(ctx, 0, buf);
931 pad = priv_len - buf->len;
932 buf->len = saved_len;
933 buf->len -= pad;
934 /* The upper layers assume the buffer is aligned on 4-byte boundaries.
935 * In the krb5p case, at least, the data ends up offset, so we need to
936 * move it around. */
937 /* XXX: This is very inefficient. It would be better to either do
938 * this while we encrypt, or maybe in the receive code, if we can peak
939 * ahead and work out the service and mechanism there. */
940 offset = buf->head[0].iov_len % 4;
941 if (offset) {
942 buf->buflen = RPCSVC_MAXPAYLOAD;
943 xdr_shift_buf(buf, offset);
944 fix_priv_head(buf, pad);
945 }
946 if (maj_stat != GSS_S_COMPLETE)
947 return -EINVAL;
948out_seq:
949 if (svc_getnl(&buf->head[0]) != seq)
950 return -EINVAL;
951 return 0;
952}
953
954struct gss_svc_data {
955 /* decoded gss client cred: */
956 struct rpc_gss_wire_cred clcred;
957 /* save a pointer to the beginning of the encoded verifier,
958 * for use in encryption/checksumming in svcauth_gss_release: */
959 __be32 *verf_start;
960 struct rsc *rsci;
961};
962
963static int
964svcauth_gss_set_client(struct svc_rqst *rqstp)
965{
966 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
967 struct rsc *rsci = svcdata->rsci;
968 struct rpc_gss_wire_cred *gc = &svcdata->clcred;
969 int stat;
970
971 /*
972 * A gss export can be specified either by:
973 * export *(sec=krb5,rw)
974 * or by
975 * export gss/krb5(rw)
976 * The latter is deprecated; but for backwards compatibility reasons
977 * the nfsd code will still fall back on trying it if the former
978 * doesn't work; so we try to make both available to nfsd, below.
979 */
980 rqstp->rq_gssclient = find_gss_auth_domain(rsci->mechctx, gc->gc_svc);
981 if (rqstp->rq_gssclient == NULL)
982 return SVC_DENIED;
983 stat = svcauth_unix_set_client(rqstp);
984 if (stat == SVC_DROP || stat == SVC_CLOSE)
985 return stat;
986 return SVC_OK;
987}
988
989static inline int
990gss_write_init_verf(struct cache_detail *cd, struct svc_rqst *rqstp,
991 struct xdr_netobj *out_handle, int *major_status)
992{
993 struct rsc *rsci;
994 int rc;
995
996 if (*major_status != GSS_S_COMPLETE)
997 return gss_write_null_verf(rqstp);
998 rsci = gss_svc_searchbyctx(cd, out_handle);
999 if (rsci == NULL) {
1000 *major_status = GSS_S_NO_CONTEXT;
1001 return gss_write_null_verf(rqstp);
1002 }
1003 rc = gss_write_verf(rqstp, rsci->mechctx, GSS_SEQ_WIN);
1004 cache_put(&rsci->h, cd);
1005 return rc;
1006}
1007
1008static inline int
1009gss_read_common_verf(struct rpc_gss_wire_cred *gc,
1010 struct kvec *argv, __be32 *authp,
1011 struct xdr_netobj *in_handle)
1012{
1013 /* Read the verifier; should be NULL: */
1014 *authp = rpc_autherr_badverf;
1015 if (argv->iov_len < 2 * 4)
1016 return SVC_DENIED;
1017 if (svc_getnl(argv) != RPC_AUTH_NULL)
1018 return SVC_DENIED;
1019 if (svc_getnl(argv) != 0)
1020 return SVC_DENIED;
1021 /* Martial context handle and token for upcall: */
1022 *authp = rpc_autherr_badcred;
1023 if (gc->gc_proc == RPC_GSS_PROC_INIT && gc->gc_ctx.len != 0)
1024 return SVC_DENIED;
1025 if (dup_netobj(in_handle, &gc->gc_ctx))
1026 return SVC_CLOSE;
1027 *authp = rpc_autherr_badverf;
1028
1029 return 0;
1030}
1031
1032static inline int
1033gss_read_verf(struct rpc_gss_wire_cred *gc,
1034 struct kvec *argv, __be32 *authp,
1035 struct xdr_netobj *in_handle,
1036 struct xdr_netobj *in_token)
1037{
1038 struct xdr_netobj tmpobj;
1039 int res;
1040
1041 res = gss_read_common_verf(gc, argv, authp, in_handle);
1042 if (res)
1043 return res;
1044
1045 if (svc_safe_getnetobj(argv, &tmpobj)) {
1046 kfree(in_handle->data);
1047 return SVC_DENIED;
1048 }
1049 if (dup_netobj(in_token, &tmpobj)) {
1050 kfree(in_handle->data);
1051 return SVC_CLOSE;
1052 }
1053
1054 return 0;
1055}
1056
1057/* Ok this is really heavily depending on a set of semantics in
1058 * how rqstp is set up by svc_recv and pages laid down by the
1059 * server when reading a request. We are basically guaranteed that
1060 * the token lays all down linearly across a set of pages, starting
1061 * at iov_base in rq_arg.head[0] which happens to be the first of a
1062 * set of pages stored in rq_pages[].
1063 * rq_arg.head[0].iov_base will provide us the page_base to pass
1064 * to the upcall.
1065 */
1066static inline int
1067gss_read_proxy_verf(struct svc_rqst *rqstp,
1068 struct rpc_gss_wire_cred *gc, __be32 *authp,
1069 struct xdr_netobj *in_handle,
1070 struct gssp_in_token *in_token)
1071{
1072 struct kvec *argv = &rqstp->rq_arg.head[0];
1073 u32 inlen;
1074 int res;
1075
1076 res = gss_read_common_verf(gc, argv, authp, in_handle);
1077 if (res)
1078 return res;
1079
1080 inlen = svc_getnl(argv);
1081 if (inlen > (argv->iov_len + rqstp->rq_arg.page_len))
1082 return SVC_DENIED;
1083
1084 in_token->pages = rqstp->rq_pages;
1085 in_token->page_base = (ulong)argv->iov_base & ~PAGE_MASK;
1086 in_token->page_len = inlen;
1087
1088 return 0;
1089}
1090
1091static inline int
1092gss_write_resv(struct kvec *resv, size_t size_limit,
1093 struct xdr_netobj *out_handle, struct xdr_netobj *out_token,
1094 int major_status, int minor_status)
1095{
1096 if (resv->iov_len + 4 > size_limit)
1097 return -1;
1098 svc_putnl(resv, RPC_SUCCESS);
1099 if (svc_safe_putnetobj(resv, out_handle))
1100 return -1;
1101 if (resv->iov_len + 3 * 4 > size_limit)
1102 return -1;
1103 svc_putnl(resv, major_status);
1104 svc_putnl(resv, minor_status);
1105 svc_putnl(resv, GSS_SEQ_WIN);
1106 if (svc_safe_putnetobj(resv, out_token))
1107 return -1;
1108 return 0;
1109}
1110
1111/*
1112 * Having read the cred already and found we're in the context
1113 * initiation case, read the verifier and initiate (or check the results
1114 * of) upcalls to userspace for help with context initiation. If
1115 * the upcall results are available, write the verifier and result.
1116 * Otherwise, drop the request pending an answer to the upcall.
1117 */
1118static int svcauth_gss_legacy_init(struct svc_rqst *rqstp,
1119 struct rpc_gss_wire_cred *gc, __be32 *authp)
1120{
1121 struct kvec *argv = &rqstp->rq_arg.head[0];
1122 struct kvec *resv = &rqstp->rq_res.head[0];
1123 struct rsi *rsip, rsikey;
1124 int ret;
1125 struct sunrpc_net *sn = net_generic(rqstp->rq_xprt->xpt_net, sunrpc_net_id);
1126
1127 memset(&rsikey, 0, sizeof(rsikey));
1128 ret = gss_read_verf(gc, argv, authp,
1129 &rsikey.in_handle, &rsikey.in_token);
1130 if (ret)
1131 return ret;
1132
1133 /* Perform upcall, or find upcall result: */
1134 rsip = rsi_lookup(sn->rsi_cache, &rsikey);
1135 rsi_free(&rsikey);
1136 if (!rsip)
1137 return SVC_CLOSE;
1138 if (cache_check(sn->rsi_cache, &rsip->h, &rqstp->rq_chandle) < 0)
1139 /* No upcall result: */
1140 return SVC_CLOSE;
1141
1142 ret = SVC_CLOSE;
1143 /* Got an answer to the upcall; use it: */
1144 if (gss_write_init_verf(sn->rsc_cache, rqstp,
1145 &rsip->out_handle, &rsip->major_status))
1146 goto out;
1147 if (gss_write_resv(resv, PAGE_SIZE,
1148 &rsip->out_handle, &rsip->out_token,
1149 rsip->major_status, rsip->minor_status))
1150 goto out;
1151
1152 ret = SVC_COMPLETE;
1153out:
1154 cache_put(&rsip->h, sn->rsi_cache);
1155 return ret;
1156}
1157
1158static int gss_proxy_save_rsc(struct cache_detail *cd,
1159 struct gssp_upcall_data *ud,
1160 uint64_t *handle)
1161{
1162 struct rsc rsci, *rscp = NULL;
1163 static atomic64_t ctxhctr;
1164 long long ctxh;
1165 struct gss_api_mech *gm = NULL;
1166 time_t expiry;
1167 int status = -EINVAL;
1168
1169 memset(&rsci, 0, sizeof(rsci));
1170 /* context handle */
1171 status = -ENOMEM;
1172 /* the handle needs to be just a unique id,
1173 * use a static counter */
1174 ctxh = atomic64_inc_return(&ctxhctr);
1175
1176 /* make a copy for the caller */
1177 *handle = ctxh;
1178
1179 /* make a copy for the rsc cache */
1180 if (dup_to_netobj(&rsci.handle, (char *)handle, sizeof(uint64_t)))
1181 goto out;
1182 rscp = rsc_lookup(cd, &rsci);
1183 if (!rscp)
1184 goto out;
1185
1186 /* creds */
1187 if (!ud->found_creds) {
1188 /* userspace seem buggy, we should always get at least a
1189 * mapping to nobody */
1190 dprintk("RPC: No creds found!\n");
1191 goto out;
1192 } else {
1193
1194 /* steal creds */
1195 rsci.cred = ud->creds;
1196 memset(&ud->creds, 0, sizeof(struct svc_cred));
1197
1198 status = -EOPNOTSUPP;
1199 /* get mech handle from OID */
1200 gm = gss_mech_get_by_OID(&ud->mech_oid);
1201 if (!gm)
1202 goto out;
1203 rsci.cred.cr_gss_mech = gm;
1204
1205 status = -EINVAL;
1206 /* mech-specific data: */
1207 status = gss_import_sec_context(ud->out_handle.data,
1208 ud->out_handle.len,
1209 gm, &rsci.mechctx,
1210 &expiry, GFP_KERNEL);
1211 if (status)
1212 goto out;
1213 }
1214
1215 rsci.h.expiry_time = expiry;
1216 rscp = rsc_update(cd, &rsci, rscp);
1217 status = 0;
1218out:
1219 rsc_free(&rsci);
1220 if (rscp)
1221 cache_put(&rscp->h, cd);
1222 else
1223 status = -ENOMEM;
1224 return status;
1225}
1226
1227static int svcauth_gss_proxy_init(struct svc_rqst *rqstp,
1228 struct rpc_gss_wire_cred *gc, __be32 *authp)
1229{
1230 struct kvec *resv = &rqstp->rq_res.head[0];
1231 struct xdr_netobj cli_handle;
1232 struct gssp_upcall_data ud;
1233 uint64_t handle;
1234 int status;
1235 int ret;
1236 struct net *net = rqstp->rq_xprt->xpt_net;
1237 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1238
1239 memset(&ud, 0, sizeof(ud));
1240 ret = gss_read_proxy_verf(rqstp, gc, authp,
1241 &ud.in_handle, &ud.in_token);
1242 if (ret)
1243 return ret;
1244
1245 ret = SVC_CLOSE;
1246
1247 /* Perform synchronous upcall to gss-proxy */
1248 status = gssp_accept_sec_context_upcall(net, &ud);
1249 if (status)
1250 goto out;
1251
1252 dprintk("RPC: svcauth_gss: gss major status = %d "
1253 "minor status = %d\n",
1254 ud.major_status, ud.minor_status);
1255
1256 switch (ud.major_status) {
1257 case GSS_S_CONTINUE_NEEDED:
1258 cli_handle = ud.out_handle;
1259 break;
1260 case GSS_S_COMPLETE:
1261 status = gss_proxy_save_rsc(sn->rsc_cache, &ud, &handle);
1262 if (status)
1263 goto out;
1264 cli_handle.data = (u8 *)&handle;
1265 cli_handle.len = sizeof(handle);
1266 break;
1267 default:
1268 ret = SVC_CLOSE;
1269 goto out;
1270 }
1271
1272 /* Got an answer to the upcall; use it: */
1273 if (gss_write_init_verf(sn->rsc_cache, rqstp,
1274 &cli_handle, &ud.major_status))
1275 goto out;
1276 if (gss_write_resv(resv, PAGE_SIZE,
1277 &cli_handle, &ud.out_token,
1278 ud.major_status, ud.minor_status))
1279 goto out;
1280
1281 ret = SVC_COMPLETE;
1282out:
1283 gssp_free_upcall_data(&ud);
1284 return ret;
1285}
1286
1287/*
1288 * Try to set the sn->use_gss_proxy variable to a new value. We only allow
1289 * it to be changed if it's currently undefined (-1). If it's any other value
1290 * then return -EBUSY unless the type wouldn't have changed anyway.
1291 */
1292static int set_gss_proxy(struct net *net, int type)
1293{
1294 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1295 int ret;
1296
1297 WARN_ON_ONCE(type != 0 && type != 1);
1298 ret = cmpxchg(&sn->use_gss_proxy, -1, type);
1299 if (ret != -1 && ret != type)
1300 return -EBUSY;
1301 return 0;
1302}
1303
1304static bool use_gss_proxy(struct net *net)
1305{
1306 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1307
1308 /* If use_gss_proxy is still undefined, then try to disable it */
1309 if (sn->use_gss_proxy == -1)
1310 set_gss_proxy(net, 0);
1311 return sn->use_gss_proxy;
1312}
1313
1314#ifdef CONFIG_PROC_FS
1315
1316static ssize_t write_gssp(struct file *file, const char __user *buf,
1317 size_t count, loff_t *ppos)
1318{
1319 struct net *net = PDE_DATA(file_inode(file));
1320 char tbuf[20];
1321 unsigned long i;
1322 int res;
1323
1324 if (*ppos || count > sizeof(tbuf)-1)
1325 return -EINVAL;
1326 if (copy_from_user(tbuf, buf, count))
1327 return -EFAULT;
1328
1329 tbuf[count] = 0;
1330 res = kstrtoul(tbuf, 0, &i);
1331 if (res)
1332 return res;
1333 if (i != 1)
1334 return -EINVAL;
1335 res = set_gssp_clnt(net);
1336 if (res)
1337 return res;
1338 res = set_gss_proxy(net, 1);
1339 if (res)
1340 return res;
1341 return count;
1342}
1343
1344static ssize_t read_gssp(struct file *file, char __user *buf,
1345 size_t count, loff_t *ppos)
1346{
1347 struct net *net = PDE_DATA(file_inode(file));
1348 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1349 unsigned long p = *ppos;
1350 char tbuf[10];
1351 size_t len;
1352
1353 snprintf(tbuf, sizeof(tbuf), "%d\n", sn->use_gss_proxy);
1354 len = strlen(tbuf);
1355 if (p >= len)
1356 return 0;
1357 len -= p;
1358 if (len > count)
1359 len = count;
1360 if (copy_to_user(buf, (void *)(tbuf+p), len))
1361 return -EFAULT;
1362 *ppos += len;
1363 return len;
1364}
1365
1366static const struct file_operations use_gss_proxy_ops = {
1367 .open = nonseekable_open,
1368 .write = write_gssp,
1369 .read = read_gssp,
1370};
1371
1372static int create_use_gss_proxy_proc_entry(struct net *net)
1373{
1374 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1375 struct proc_dir_entry **p = &sn->use_gssp_proc;
1376
1377 sn->use_gss_proxy = -1;
1378 *p = proc_create_data("use-gss-proxy", S_IFREG | 0600,
1379 sn->proc_net_rpc,
1380 &use_gss_proxy_ops, net);
1381 if (!*p)
1382 return -ENOMEM;
1383 init_gssp_clnt(sn);
1384 return 0;
1385}
1386
1387static void destroy_use_gss_proxy_proc_entry(struct net *net)
1388{
1389 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1390
1391 if (sn->use_gssp_proc) {
1392 remove_proc_entry("use-gss-proxy", sn->proc_net_rpc);
1393 clear_gssp_clnt(sn);
1394 }
1395}
1396#else /* CONFIG_PROC_FS */
1397
1398static int create_use_gss_proxy_proc_entry(struct net *net)
1399{
1400 return 0;
1401}
1402
1403static void destroy_use_gss_proxy_proc_entry(struct net *net) {}
1404
1405#endif /* CONFIG_PROC_FS */
1406
1407/*
1408 * Accept an rpcsec packet.
1409 * If context establishment, punt to user space
1410 * If data exchange, verify/decrypt
1411 * If context destruction, handle here
1412 * In the context establishment and destruction case we encode
1413 * response here and return SVC_COMPLETE.
1414 */
1415static int
1416svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
1417{
1418 struct kvec *argv = &rqstp->rq_arg.head[0];
1419 struct kvec *resv = &rqstp->rq_res.head[0];
1420 u32 crlen;
1421 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
1422 struct rpc_gss_wire_cred *gc;
1423 struct rsc *rsci = NULL;
1424 __be32 *rpcstart;
1425 __be32 *reject_stat = resv->iov_base + resv->iov_len;
1426 int ret;
1427 struct sunrpc_net *sn = net_generic(rqstp->rq_xprt->xpt_net, sunrpc_net_id);
1428
1429 dprintk("RPC: svcauth_gss: argv->iov_len = %zd\n",
1430 argv->iov_len);
1431
1432 *authp = rpc_autherr_badcred;
1433 if (!svcdata)
1434 svcdata = kmalloc(sizeof(*svcdata), GFP_KERNEL);
1435 if (!svcdata)
1436 goto auth_err;
1437 rqstp->rq_auth_data = svcdata;
1438 svcdata->verf_start = NULL;
1439 svcdata->rsci = NULL;
1440 gc = &svcdata->clcred;
1441
1442 /* start of rpc packet is 7 u32's back from here:
1443 * xid direction rpcversion prog vers proc flavour
1444 */
1445 rpcstart = argv->iov_base;
1446 rpcstart -= 7;
1447
1448 /* credential is:
1449 * version(==1), proc(0,1,2,3), seq, service (1,2,3), handle
1450 * at least 5 u32s, and is preceded by length, so that makes 6.
1451 */
1452
1453 if (argv->iov_len < 5 * 4)
1454 goto auth_err;
1455 crlen = svc_getnl(argv);
1456 if (svc_getnl(argv) != RPC_GSS_VERSION)
1457 goto auth_err;
1458 gc->gc_proc = svc_getnl(argv);
1459 gc->gc_seq = svc_getnl(argv);
1460 gc->gc_svc = svc_getnl(argv);
1461 if (svc_safe_getnetobj(argv, &gc->gc_ctx))
1462 goto auth_err;
1463 if (crlen != round_up_to_quad(gc->gc_ctx.len) + 5 * 4)
1464 goto auth_err;
1465
1466 if ((gc->gc_proc != RPC_GSS_PROC_DATA) && (rqstp->rq_proc != 0))
1467 goto auth_err;
1468
1469 *authp = rpc_autherr_badverf;
1470 switch (gc->gc_proc) {
1471 case RPC_GSS_PROC_INIT:
1472 case RPC_GSS_PROC_CONTINUE_INIT:
1473 if (use_gss_proxy(SVC_NET(rqstp)))
1474 return svcauth_gss_proxy_init(rqstp, gc, authp);
1475 else
1476 return svcauth_gss_legacy_init(rqstp, gc, authp);
1477 case RPC_GSS_PROC_DATA:
1478 case RPC_GSS_PROC_DESTROY:
1479 /* Look up the context, and check the verifier: */
1480 *authp = rpcsec_gsserr_credproblem;
1481 rsci = gss_svc_searchbyctx(sn->rsc_cache, &gc->gc_ctx);
1482 if (!rsci)
1483 goto auth_err;
1484 switch (gss_verify_header(rqstp, rsci, rpcstart, gc, authp)) {
1485 case SVC_OK:
1486 break;
1487 case SVC_DENIED:
1488 goto auth_err;
1489 case SVC_DROP:
1490 goto drop;
1491 }
1492 break;
1493 default:
1494 *authp = rpc_autherr_rejectedcred;
1495 goto auth_err;
1496 }
1497
1498 /* now act upon the command: */
1499 switch (gc->gc_proc) {
1500 case RPC_GSS_PROC_DESTROY:
1501 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
1502 goto auth_err;
1503 /* Delete the entry from the cache_list and call cache_put */
1504 sunrpc_cache_unhash(sn->rsc_cache, &rsci->h);
1505 if (resv->iov_len + 4 > PAGE_SIZE)
1506 goto drop;
1507 svc_putnl(resv, RPC_SUCCESS);
1508 goto complete;
1509 case RPC_GSS_PROC_DATA:
1510 *authp = rpcsec_gsserr_ctxproblem;
1511 svcdata->verf_start = resv->iov_base + resv->iov_len;
1512 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
1513 goto auth_err;
1514 rqstp->rq_cred = rsci->cred;
1515 get_group_info(rsci->cred.cr_group_info);
1516 *authp = rpc_autherr_badcred;
1517 switch (gc->gc_svc) {
1518 case RPC_GSS_SVC_NONE:
1519 break;
1520 case RPC_GSS_SVC_INTEGRITY:
1521 /* placeholders for length and seq. number: */
1522 svc_putnl(resv, 0);
1523 svc_putnl(resv, 0);
1524 if (unwrap_integ_data(rqstp, &rqstp->rq_arg,
1525 gc->gc_seq, rsci->mechctx))
1526 goto garbage_args;
1527 rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE;
1528 break;
1529 case RPC_GSS_SVC_PRIVACY:
1530 /* placeholders for length and seq. number: */
1531 svc_putnl(resv, 0);
1532 svc_putnl(resv, 0);
1533 if (unwrap_priv_data(rqstp, &rqstp->rq_arg,
1534 gc->gc_seq, rsci->mechctx))
1535 goto garbage_args;
1536 rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE * 2;
1537 break;
1538 default:
1539 goto auth_err;
1540 }
1541 svcdata->rsci = rsci;
1542 cache_get(&rsci->h);
1543 rqstp->rq_cred.cr_flavor = gss_svc_to_pseudoflavor(
1544 rsci->mechctx->mech_type,
1545 GSS_C_QOP_DEFAULT,
1546 gc->gc_svc);
1547 ret = SVC_OK;
1548 goto out;
1549 }
1550garbage_args:
1551 ret = SVC_GARBAGE;
1552 goto out;
1553auth_err:
1554 /* Restore write pointer to its original value: */
1555 xdr_ressize_check(rqstp, reject_stat);
1556 ret = SVC_DENIED;
1557 goto out;
1558complete:
1559 ret = SVC_COMPLETE;
1560 goto out;
1561drop:
1562 ret = SVC_CLOSE;
1563out:
1564 if (rsci)
1565 cache_put(&rsci->h, sn->rsc_cache);
1566 return ret;
1567}
1568
1569static __be32 *
1570svcauth_gss_prepare_to_wrap(struct xdr_buf *resbuf, struct gss_svc_data *gsd)
1571{
1572 __be32 *p;
1573 u32 verf_len;
1574
1575 p = gsd->verf_start;
1576 gsd->verf_start = NULL;
1577
1578 /* If the reply stat is nonzero, don't wrap: */
1579 if (*(p-1) != rpc_success)
1580 return NULL;
1581 /* Skip the verifier: */
1582 p += 1;
1583 verf_len = ntohl(*p++);
1584 p += XDR_QUADLEN(verf_len);
1585 /* move accept_stat to right place: */
1586 memcpy(p, p + 2, 4);
1587 /* Also don't wrap if the accept stat is nonzero: */
1588 if (*p != rpc_success) {
1589 resbuf->head[0].iov_len -= 2 * 4;
1590 return NULL;
1591 }
1592 p++;
1593 return p;
1594}
1595
1596static inline int
1597svcauth_gss_wrap_resp_integ(struct svc_rqst *rqstp)
1598{
1599 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1600 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1601 struct xdr_buf *resbuf = &rqstp->rq_res;
1602 struct xdr_buf integ_buf;
1603 struct xdr_netobj mic;
1604 struct kvec *resv;
1605 __be32 *p;
1606 int integ_offset, integ_len;
1607 int stat = -EINVAL;
1608
1609 p = svcauth_gss_prepare_to_wrap(resbuf, gsd);
1610 if (p == NULL)
1611 goto out;
1612 integ_offset = (u8 *)(p + 1) - (u8 *)resbuf->head[0].iov_base;
1613 integ_len = resbuf->len - integ_offset;
1614 BUG_ON(integ_len % 4);
1615 *p++ = htonl(integ_len);
1616 *p++ = htonl(gc->gc_seq);
1617 if (xdr_buf_subsegment(resbuf, &integ_buf, integ_offset, integ_len)) {
1618 WARN_ON_ONCE(1);
1619 goto out_err;
1620 }
1621 if (resbuf->tail[0].iov_base == NULL) {
1622 if (resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1623 goto out_err;
1624 resbuf->tail[0].iov_base = resbuf->head[0].iov_base
1625 + resbuf->head[0].iov_len;
1626 resbuf->tail[0].iov_len = 0;
1627 }
1628 resv = &resbuf->tail[0];
1629 mic.data = (u8 *)resv->iov_base + resv->iov_len + 4;
1630 if (gss_get_mic(gsd->rsci->mechctx, &integ_buf, &mic))
1631 goto out_err;
1632 svc_putnl(resv, mic.len);
1633 memset(mic.data + mic.len, 0,
1634 round_up_to_quad(mic.len) - mic.len);
1635 resv->iov_len += XDR_QUADLEN(mic.len) << 2;
1636 /* not strictly required: */
1637 resbuf->len += XDR_QUADLEN(mic.len) << 2;
1638 BUG_ON(resv->iov_len > PAGE_SIZE);
1639out:
1640 stat = 0;
1641out_err:
1642 return stat;
1643}
1644
1645static inline int
1646svcauth_gss_wrap_resp_priv(struct svc_rqst *rqstp)
1647{
1648 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1649 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1650 struct xdr_buf *resbuf = &rqstp->rq_res;
1651 struct page **inpages = NULL;
1652 __be32 *p, *len;
1653 int offset;
1654 int pad;
1655
1656 p = svcauth_gss_prepare_to_wrap(resbuf, gsd);
1657 if (p == NULL)
1658 return 0;
1659 len = p++;
1660 offset = (u8 *)p - (u8 *)resbuf->head[0].iov_base;
1661 *p++ = htonl(gc->gc_seq);
1662 inpages = resbuf->pages;
1663 /* XXX: Would be better to write some xdr helper functions for
1664 * nfs{2,3,4}xdr.c that place the data right, instead of copying: */
1665
1666 /*
1667 * If there is currently tail data, make sure there is
1668 * room for the head, tail, and 2 * RPC_MAX_AUTH_SIZE in
1669 * the page, and move the current tail data such that
1670 * there is RPC_MAX_AUTH_SIZE slack space available in
1671 * both the head and tail.
1672 */
1673 if (resbuf->tail[0].iov_base) {
1674 BUG_ON(resbuf->tail[0].iov_base >= resbuf->head[0].iov_base
1675 + PAGE_SIZE);
1676 BUG_ON(resbuf->tail[0].iov_base < resbuf->head[0].iov_base);
1677 if (resbuf->tail[0].iov_len + resbuf->head[0].iov_len
1678 + 2 * RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1679 return -ENOMEM;
1680 memmove(resbuf->tail[0].iov_base + RPC_MAX_AUTH_SIZE,
1681 resbuf->tail[0].iov_base,
1682 resbuf->tail[0].iov_len);
1683 resbuf->tail[0].iov_base += RPC_MAX_AUTH_SIZE;
1684 }
1685 /*
1686 * If there is no current tail data, make sure there is
1687 * room for the head data, and 2 * RPC_MAX_AUTH_SIZE in the
1688 * allotted page, and set up tail information such that there
1689 * is RPC_MAX_AUTH_SIZE slack space available in both the
1690 * head and tail.
1691 */
1692 if (resbuf->tail[0].iov_base == NULL) {
1693 if (resbuf->head[0].iov_len + 2*RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1694 return -ENOMEM;
1695 resbuf->tail[0].iov_base = resbuf->head[0].iov_base
1696 + resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE;
1697 resbuf->tail[0].iov_len = 0;
1698 }
1699 if (gss_wrap(gsd->rsci->mechctx, offset, resbuf, inpages))
1700 return -ENOMEM;
1701 *len = htonl(resbuf->len - offset);
1702 pad = 3 - ((resbuf->len - offset - 1)&3);
1703 p = (__be32 *)(resbuf->tail[0].iov_base + resbuf->tail[0].iov_len);
1704 memset(p, 0, pad);
1705 resbuf->tail[0].iov_len += pad;
1706 resbuf->len += pad;
1707 return 0;
1708}
1709
1710static int
1711svcauth_gss_release(struct svc_rqst *rqstp)
1712{
1713 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1714 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1715 struct xdr_buf *resbuf = &rqstp->rq_res;
1716 int stat = -EINVAL;
1717 struct sunrpc_net *sn = net_generic(rqstp->rq_xprt->xpt_net, sunrpc_net_id);
1718
1719 if (gc->gc_proc != RPC_GSS_PROC_DATA)
1720 goto out;
1721 /* Release can be called twice, but we only wrap once. */
1722 if (gsd->verf_start == NULL)
1723 goto out;
1724 /* normally not set till svc_send, but we need it here: */
1725 /* XXX: what for? Do we mess it up the moment we call svc_putu32
1726 * or whatever? */
1727 resbuf->len = total_buf_len(resbuf);
1728 switch (gc->gc_svc) {
1729 case RPC_GSS_SVC_NONE:
1730 break;
1731 case RPC_GSS_SVC_INTEGRITY:
1732 stat = svcauth_gss_wrap_resp_integ(rqstp);
1733 if (stat)
1734 goto out_err;
1735 break;
1736 case RPC_GSS_SVC_PRIVACY:
1737 stat = svcauth_gss_wrap_resp_priv(rqstp);
1738 if (stat)
1739 goto out_err;
1740 break;
1741 /*
1742 * For any other gc_svc value, svcauth_gss_accept() already set
1743 * the auth_error appropriately; just fall through:
1744 */
1745 }
1746
1747out:
1748 stat = 0;
1749out_err:
1750 if (rqstp->rq_client)
1751 auth_domain_put(rqstp->rq_client);
1752 rqstp->rq_client = NULL;
1753 if (rqstp->rq_gssclient)
1754 auth_domain_put(rqstp->rq_gssclient);
1755 rqstp->rq_gssclient = NULL;
1756 if (rqstp->rq_cred.cr_group_info)
1757 put_group_info(rqstp->rq_cred.cr_group_info);
1758 rqstp->rq_cred.cr_group_info = NULL;
1759 if (gsd->rsci)
1760 cache_put(&gsd->rsci->h, sn->rsc_cache);
1761 gsd->rsci = NULL;
1762
1763 return stat;
1764}
1765
1766static void
1767svcauth_gss_domain_release(struct auth_domain *dom)
1768{
1769 struct gss_domain *gd = container_of(dom, struct gss_domain, h);
1770
1771 kfree(dom->name);
1772 kfree(gd);
1773}
1774
1775static struct auth_ops svcauthops_gss = {
1776 .name = "rpcsec_gss",
1777 .owner = THIS_MODULE,
1778 .flavour = RPC_AUTH_GSS,
1779 .accept = svcauth_gss_accept,
1780 .release = svcauth_gss_release,
1781 .domain_release = svcauth_gss_domain_release,
1782 .set_client = svcauth_gss_set_client,
1783};
1784
1785static int rsi_cache_create_net(struct net *net)
1786{
1787 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1788 struct cache_detail *cd;
1789 int err;
1790
1791 cd = cache_create_net(&rsi_cache_template, net);
1792 if (IS_ERR(cd))
1793 return PTR_ERR(cd);
1794 err = cache_register_net(cd, net);
1795 if (err) {
1796 cache_destroy_net(cd, net);
1797 return err;
1798 }
1799 sn->rsi_cache = cd;
1800 return 0;
1801}
1802
1803static void rsi_cache_destroy_net(struct net *net)
1804{
1805 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1806 struct cache_detail *cd = sn->rsi_cache;
1807
1808 sn->rsi_cache = NULL;
1809 cache_purge(cd);
1810 cache_unregister_net(cd, net);
1811 cache_destroy_net(cd, net);
1812}
1813
1814static int rsc_cache_create_net(struct net *net)
1815{
1816 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1817 struct cache_detail *cd;
1818 int err;
1819
1820 cd = cache_create_net(&rsc_cache_template, net);
1821 if (IS_ERR(cd))
1822 return PTR_ERR(cd);
1823 err = cache_register_net(cd, net);
1824 if (err) {
1825 cache_destroy_net(cd, net);
1826 return err;
1827 }
1828 sn->rsc_cache = cd;
1829 return 0;
1830}
1831
1832static void rsc_cache_destroy_net(struct net *net)
1833{
1834 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1835 struct cache_detail *cd = sn->rsc_cache;
1836
1837 sn->rsc_cache = NULL;
1838 cache_purge(cd);
1839 cache_unregister_net(cd, net);
1840 cache_destroy_net(cd, net);
1841}
1842
1843int
1844gss_svc_init_net(struct net *net)
1845{
1846 int rv;
1847
1848 rv = rsc_cache_create_net(net);
1849 if (rv)
1850 return rv;
1851 rv = rsi_cache_create_net(net);
1852 if (rv)
1853 goto out1;
1854 rv = create_use_gss_proxy_proc_entry(net);
1855 if (rv)
1856 goto out2;
1857 return 0;
1858out2:
1859 destroy_use_gss_proxy_proc_entry(net);
1860out1:
1861 rsc_cache_destroy_net(net);
1862 return rv;
1863}
1864
1865void
1866gss_svc_shutdown_net(struct net *net)
1867{
1868 destroy_use_gss_proxy_proc_entry(net);
1869 rsi_cache_destroy_net(net);
1870 rsc_cache_destroy_net(net);
1871}
1872
1873int
1874gss_svc_init(void)
1875{
1876 return svc_auth_register(RPC_AUTH_GSS, &svcauthops_gss);
1877}
1878
1879void
1880gss_svc_shutdown(void)
1881{
1882 svc_auth_unregister(RPC_AUTH_GSS);
1883}