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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Neil Brown <neilb@cse.unsw.edu.au>
4 * J. Bruce Fields <bfields@umich.edu>
5 * Andy Adamson <andros@umich.edu>
6 * Dug Song <dugsong@monkey.org>
7 *
8 * RPCSEC_GSS server authentication.
9 * This implements RPCSEC_GSS as defined in rfc2203 (rpcsec_gss) and rfc2078
10 * (gssapi)
11 *
12 * The RPCSEC_GSS involves three stages:
13 * 1/ context creation
14 * 2/ data exchange
15 * 3/ context destruction
16 *
17 * Context creation is handled largely by upcalls to user-space.
18 * In particular, GSS_Accept_sec_context is handled by an upcall
19 * Data exchange is handled entirely within the kernel
20 * In particular, GSS_GetMIC, GSS_VerifyMIC, GSS_Seal, GSS_Unseal are in-kernel.
21 * Context destruction is handled in-kernel
22 * GSS_Delete_sec_context is in-kernel
23 *
24 * Context creation is initiated by a RPCSEC_GSS_INIT request arriving.
25 * The context handle and gss_token are used as a key into the rpcsec_init cache.
26 * The content of this cache includes some of the outputs of GSS_Accept_sec_context,
27 * being major_status, minor_status, context_handle, reply_token.
28 * These are sent back to the client.
29 * Sequence window management is handled by the kernel. The window size if currently
30 * a compile time constant.
31 *
32 * When user-space is happy that a context is established, it places an entry
33 * in the rpcsec_context cache. The key for this cache is the context_handle.
34 * The content includes:
35 * uid/gidlist - for determining access rights
36 * mechanism type
37 * mechanism specific information, such as a key
38 *
39 */
40
41#include <linux/slab.h>
42#include <linux/types.h>
43#include <linux/module.h>
44#include <linux/pagemap.h>
45#include <linux/user_namespace.h>
46
47#include <linux/sunrpc/auth_gss.h>
48#include <linux/sunrpc/gss_err.h>
49#include <linux/sunrpc/svcauth.h>
50#include <linux/sunrpc/svcauth_gss.h>
51#include <linux/sunrpc/cache.h>
52#include <linux/sunrpc/gss_krb5.h>
53
54#include <trace/events/rpcgss.h>
55
56#include "gss_rpc_upcall.h"
57
58/*
59 * Unfortunately there isn't a maximum checksum size exported via the
60 * GSS API. Manufacture one based on GSS mechanisms supported by this
61 * implementation.
62 */
63#define GSS_MAX_CKSUMSIZE (GSS_KRB5_TOK_HDR_LEN + GSS_KRB5_MAX_CKSUM_LEN)
64
65/*
66 * This value may be increased in the future to accommodate other
67 * usage of the scratch buffer.
68 */
69#define GSS_SCRATCH_SIZE GSS_MAX_CKSUMSIZE
70
71struct gss_svc_data {
72 /* decoded gss client cred: */
73 struct rpc_gss_wire_cred clcred;
74 /* save a pointer to the beginning of the encoded verifier,
75 * for use in encryption/checksumming in svcauth_gss_release: */
76 __be32 *verf_start;
77 struct rsc *rsci;
78
79 /* for temporary results */
80 u8 gsd_scratch[GSS_SCRATCH_SIZE];
81};
82
83/* The rpcsec_init cache is used for mapping RPCSEC_GSS_{,CONT_}INIT requests
84 * into replies.
85 *
86 * Key is context handle (\x if empty) and gss_token.
87 * Content is major_status minor_status (integers) context_handle, reply_token.
88 *
89 */
90
91static int netobj_equal(struct xdr_netobj *a, struct xdr_netobj *b)
92{
93 return a->len == b->len && 0 == memcmp(a->data, b->data, a->len);
94}
95
96#define RSI_HASHBITS 6
97#define RSI_HASHMAX (1<<RSI_HASHBITS)
98
99struct rsi {
100 struct cache_head h;
101 struct xdr_netobj in_handle, in_token;
102 struct xdr_netobj out_handle, out_token;
103 int major_status, minor_status;
104 struct rcu_head rcu_head;
105};
106
107static struct rsi *rsi_update(struct cache_detail *cd, struct rsi *new, struct rsi *old);
108static struct rsi *rsi_lookup(struct cache_detail *cd, struct rsi *item);
109
110static void rsi_free(struct rsi *rsii)
111{
112 kfree(rsii->in_handle.data);
113 kfree(rsii->in_token.data);
114 kfree(rsii->out_handle.data);
115 kfree(rsii->out_token.data);
116}
117
118static void rsi_free_rcu(struct rcu_head *head)
119{
120 struct rsi *rsii = container_of(head, struct rsi, rcu_head);
121
122 rsi_free(rsii);
123 kfree(rsii);
124}
125
126static void rsi_put(struct kref *ref)
127{
128 struct rsi *rsii = container_of(ref, struct rsi, h.ref);
129
130 call_rcu(&rsii->rcu_head, rsi_free_rcu);
131}
132
133static inline int rsi_hash(struct rsi *item)
134{
135 return hash_mem(item->in_handle.data, item->in_handle.len, RSI_HASHBITS)
136 ^ hash_mem(item->in_token.data, item->in_token.len, RSI_HASHBITS);
137}
138
139static int rsi_match(struct cache_head *a, struct cache_head *b)
140{
141 struct rsi *item = container_of(a, struct rsi, h);
142 struct rsi *tmp = container_of(b, struct rsi, h);
143 return netobj_equal(&item->in_handle, &tmp->in_handle) &&
144 netobj_equal(&item->in_token, &tmp->in_token);
145}
146
147static int dup_to_netobj(struct xdr_netobj *dst, char *src, int len)
148{
149 dst->len = len;
150 dst->data = (len ? kmemdup(src, len, GFP_KERNEL) : NULL);
151 if (len && !dst->data)
152 return -ENOMEM;
153 return 0;
154}
155
156static inline int dup_netobj(struct xdr_netobj *dst, struct xdr_netobj *src)
157{
158 return dup_to_netobj(dst, src->data, src->len);
159}
160
161static void rsi_init(struct cache_head *cnew, struct cache_head *citem)
162{
163 struct rsi *new = container_of(cnew, struct rsi, h);
164 struct rsi *item = container_of(citem, struct rsi, h);
165
166 new->out_handle.data = NULL;
167 new->out_handle.len = 0;
168 new->out_token.data = NULL;
169 new->out_token.len = 0;
170 new->in_handle.len = item->in_handle.len;
171 item->in_handle.len = 0;
172 new->in_token.len = item->in_token.len;
173 item->in_token.len = 0;
174 new->in_handle.data = item->in_handle.data;
175 item->in_handle.data = NULL;
176 new->in_token.data = item->in_token.data;
177 item->in_token.data = NULL;
178}
179
180static void update_rsi(struct cache_head *cnew, struct cache_head *citem)
181{
182 struct rsi *new = container_of(cnew, struct rsi, h);
183 struct rsi *item = container_of(citem, struct rsi, h);
184
185 BUG_ON(new->out_handle.data || new->out_token.data);
186 new->out_handle.len = item->out_handle.len;
187 item->out_handle.len = 0;
188 new->out_token.len = item->out_token.len;
189 item->out_token.len = 0;
190 new->out_handle.data = item->out_handle.data;
191 item->out_handle.data = NULL;
192 new->out_token.data = item->out_token.data;
193 item->out_token.data = NULL;
194
195 new->major_status = item->major_status;
196 new->minor_status = item->minor_status;
197}
198
199static struct cache_head *rsi_alloc(void)
200{
201 struct rsi *rsii = kmalloc(sizeof(*rsii), GFP_KERNEL);
202 if (rsii)
203 return &rsii->h;
204 else
205 return NULL;
206}
207
208static int rsi_upcall(struct cache_detail *cd, struct cache_head *h)
209{
210 return sunrpc_cache_pipe_upcall_timeout(cd, h);
211}
212
213static void rsi_request(struct cache_detail *cd,
214 struct cache_head *h,
215 char **bpp, int *blen)
216{
217 struct rsi *rsii = container_of(h, struct rsi, h);
218
219 qword_addhex(bpp, blen, rsii->in_handle.data, rsii->in_handle.len);
220 qword_addhex(bpp, blen, rsii->in_token.data, rsii->in_token.len);
221 (*bpp)[-1] = '\n';
222 WARN_ONCE(*blen < 0,
223 "RPCSEC/GSS credential too large - please use gssproxy\n");
224}
225
226static int rsi_parse(struct cache_detail *cd,
227 char *mesg, int mlen)
228{
229 /* context token expiry major minor context token */
230 char *buf = mesg;
231 char *ep;
232 int len;
233 struct rsi rsii, *rsip = NULL;
234 time64_t expiry;
235 int status = -EINVAL;
236
237 memset(&rsii, 0, sizeof(rsii));
238 /* handle */
239 len = qword_get(&mesg, buf, mlen);
240 if (len < 0)
241 goto out;
242 status = -ENOMEM;
243 if (dup_to_netobj(&rsii.in_handle, buf, len))
244 goto out;
245
246 /* token */
247 len = qword_get(&mesg, buf, mlen);
248 status = -EINVAL;
249 if (len < 0)
250 goto out;
251 status = -ENOMEM;
252 if (dup_to_netobj(&rsii.in_token, buf, len))
253 goto out;
254
255 rsip = rsi_lookup(cd, &rsii);
256 if (!rsip)
257 goto out;
258
259 rsii.h.flags = 0;
260 /* expiry */
261 expiry = get_expiry(&mesg);
262 status = -EINVAL;
263 if (expiry == 0)
264 goto out;
265
266 /* major/minor */
267 len = qword_get(&mesg, buf, mlen);
268 if (len <= 0)
269 goto out;
270 rsii.major_status = simple_strtoul(buf, &ep, 10);
271 if (*ep)
272 goto out;
273 len = qword_get(&mesg, buf, mlen);
274 if (len <= 0)
275 goto out;
276 rsii.minor_status = simple_strtoul(buf, &ep, 10);
277 if (*ep)
278 goto out;
279
280 /* out_handle */
281 len = qword_get(&mesg, buf, mlen);
282 if (len < 0)
283 goto out;
284 status = -ENOMEM;
285 if (dup_to_netobj(&rsii.out_handle, buf, len))
286 goto out;
287
288 /* out_token */
289 len = qword_get(&mesg, buf, mlen);
290 status = -EINVAL;
291 if (len < 0)
292 goto out;
293 status = -ENOMEM;
294 if (dup_to_netobj(&rsii.out_token, buf, len))
295 goto out;
296 rsii.h.expiry_time = expiry;
297 rsip = rsi_update(cd, &rsii, rsip);
298 status = 0;
299out:
300 rsi_free(&rsii);
301 if (rsip)
302 cache_put(&rsip->h, cd);
303 else
304 status = -ENOMEM;
305 return status;
306}
307
308static const struct cache_detail rsi_cache_template = {
309 .owner = THIS_MODULE,
310 .hash_size = RSI_HASHMAX,
311 .name = "auth.rpcsec.init",
312 .cache_put = rsi_put,
313 .cache_upcall = rsi_upcall,
314 .cache_request = rsi_request,
315 .cache_parse = rsi_parse,
316 .match = rsi_match,
317 .init = rsi_init,
318 .update = update_rsi,
319 .alloc = rsi_alloc,
320};
321
322static struct rsi *rsi_lookup(struct cache_detail *cd, struct rsi *item)
323{
324 struct cache_head *ch;
325 int hash = rsi_hash(item);
326
327 ch = sunrpc_cache_lookup_rcu(cd, &item->h, hash);
328 if (ch)
329 return container_of(ch, struct rsi, h);
330 else
331 return NULL;
332}
333
334static struct rsi *rsi_update(struct cache_detail *cd, struct rsi *new, struct rsi *old)
335{
336 struct cache_head *ch;
337 int hash = rsi_hash(new);
338
339 ch = sunrpc_cache_update(cd, &new->h,
340 &old->h, hash);
341 if (ch)
342 return container_of(ch, struct rsi, h);
343 else
344 return NULL;
345}
346
347
348/*
349 * The rpcsec_context cache is used to store a context that is
350 * used in data exchange.
351 * The key is a context handle. The content is:
352 * uid, gidlist, mechanism, service-set, mech-specific-data
353 */
354
355#define RSC_HASHBITS 10
356#define RSC_HASHMAX (1<<RSC_HASHBITS)
357
358#define GSS_SEQ_WIN 128
359
360struct gss_svc_seq_data {
361 /* highest seq number seen so far: */
362 u32 sd_max;
363 /* for i such that sd_max-GSS_SEQ_WIN < i <= sd_max, the i-th bit of
364 * sd_win is nonzero iff sequence number i has been seen already: */
365 unsigned long sd_win[GSS_SEQ_WIN/BITS_PER_LONG];
366 spinlock_t sd_lock;
367};
368
369struct rsc {
370 struct cache_head h;
371 struct xdr_netobj handle;
372 struct svc_cred cred;
373 struct gss_svc_seq_data seqdata;
374 struct gss_ctx *mechctx;
375 struct rcu_head rcu_head;
376};
377
378static struct rsc *rsc_update(struct cache_detail *cd, struct rsc *new, struct rsc *old);
379static struct rsc *rsc_lookup(struct cache_detail *cd, struct rsc *item);
380
381static void rsc_free(struct rsc *rsci)
382{
383 kfree(rsci->handle.data);
384 if (rsci->mechctx)
385 gss_delete_sec_context(&rsci->mechctx);
386 free_svc_cred(&rsci->cred);
387}
388
389static void rsc_free_rcu(struct rcu_head *head)
390{
391 struct rsc *rsci = container_of(head, struct rsc, rcu_head);
392
393 kfree(rsci->handle.data);
394 kfree(rsci);
395}
396
397static void rsc_put(struct kref *ref)
398{
399 struct rsc *rsci = container_of(ref, struct rsc, h.ref);
400
401 if (rsci->mechctx)
402 gss_delete_sec_context(&rsci->mechctx);
403 free_svc_cred(&rsci->cred);
404 call_rcu(&rsci->rcu_head, rsc_free_rcu);
405}
406
407static inline int
408rsc_hash(struct rsc *rsci)
409{
410 return hash_mem(rsci->handle.data, rsci->handle.len, RSC_HASHBITS);
411}
412
413static int
414rsc_match(struct cache_head *a, struct cache_head *b)
415{
416 struct rsc *new = container_of(a, struct rsc, h);
417 struct rsc *tmp = container_of(b, struct rsc, h);
418
419 return netobj_equal(&new->handle, &tmp->handle);
420}
421
422static void
423rsc_init(struct cache_head *cnew, struct cache_head *ctmp)
424{
425 struct rsc *new = container_of(cnew, struct rsc, h);
426 struct rsc *tmp = container_of(ctmp, struct rsc, h);
427
428 new->handle.len = tmp->handle.len;
429 tmp->handle.len = 0;
430 new->handle.data = tmp->handle.data;
431 tmp->handle.data = NULL;
432 new->mechctx = NULL;
433 init_svc_cred(&new->cred);
434}
435
436static void
437update_rsc(struct cache_head *cnew, struct cache_head *ctmp)
438{
439 struct rsc *new = container_of(cnew, struct rsc, h);
440 struct rsc *tmp = container_of(ctmp, struct rsc, h);
441
442 new->mechctx = tmp->mechctx;
443 tmp->mechctx = NULL;
444 memset(&new->seqdata, 0, sizeof(new->seqdata));
445 spin_lock_init(&new->seqdata.sd_lock);
446 new->cred = tmp->cred;
447 init_svc_cred(&tmp->cred);
448}
449
450static struct cache_head *
451rsc_alloc(void)
452{
453 struct rsc *rsci = kmalloc(sizeof(*rsci), GFP_KERNEL);
454 if (rsci)
455 return &rsci->h;
456 else
457 return NULL;
458}
459
460static int rsc_upcall(struct cache_detail *cd, struct cache_head *h)
461{
462 return -EINVAL;
463}
464
465static int rsc_parse(struct cache_detail *cd,
466 char *mesg, int mlen)
467{
468 /* contexthandle expiry [ uid gid N <n gids> mechname ...mechdata... ] */
469 char *buf = mesg;
470 int id;
471 int len, rv;
472 struct rsc rsci, *rscp = NULL;
473 time64_t expiry;
474 int status = -EINVAL;
475 struct gss_api_mech *gm = NULL;
476
477 memset(&rsci, 0, sizeof(rsci));
478 /* context handle */
479 len = qword_get(&mesg, buf, mlen);
480 if (len < 0) goto out;
481 status = -ENOMEM;
482 if (dup_to_netobj(&rsci.handle, buf, len))
483 goto out;
484
485 rsci.h.flags = 0;
486 /* expiry */
487 expiry = get_expiry(&mesg);
488 status = -EINVAL;
489 if (expiry == 0)
490 goto out;
491
492 rscp = rsc_lookup(cd, &rsci);
493 if (!rscp)
494 goto out;
495
496 /* uid, or NEGATIVE */
497 rv = get_int(&mesg, &id);
498 if (rv == -EINVAL)
499 goto out;
500 if (rv == -ENOENT)
501 set_bit(CACHE_NEGATIVE, &rsci.h.flags);
502 else {
503 int N, i;
504
505 /*
506 * NOTE: we skip uid_valid()/gid_valid() checks here:
507 * instead, * -1 id's are later mapped to the
508 * (export-specific) anonymous id by nfsd_setuser.
509 *
510 * (But supplementary gid's get no such special
511 * treatment so are checked for validity here.)
512 */
513 /* uid */
514 rsci.cred.cr_uid = make_kuid(current_user_ns(), id);
515
516 /* gid */
517 if (get_int(&mesg, &id))
518 goto out;
519 rsci.cred.cr_gid = make_kgid(current_user_ns(), id);
520
521 /* number of additional gid's */
522 if (get_int(&mesg, &N))
523 goto out;
524 if (N < 0 || N > NGROUPS_MAX)
525 goto out;
526 status = -ENOMEM;
527 rsci.cred.cr_group_info = groups_alloc(N);
528 if (rsci.cred.cr_group_info == NULL)
529 goto out;
530
531 /* gid's */
532 status = -EINVAL;
533 for (i=0; i<N; i++) {
534 kgid_t kgid;
535 if (get_int(&mesg, &id))
536 goto out;
537 kgid = make_kgid(current_user_ns(), id);
538 if (!gid_valid(kgid))
539 goto out;
540 rsci.cred.cr_group_info->gid[i] = kgid;
541 }
542 groups_sort(rsci.cred.cr_group_info);
543
544 /* mech name */
545 len = qword_get(&mesg, buf, mlen);
546 if (len < 0)
547 goto out;
548 gm = rsci.cred.cr_gss_mech = gss_mech_get_by_name(buf);
549 status = -EOPNOTSUPP;
550 if (!gm)
551 goto out;
552
553 status = -EINVAL;
554 /* mech-specific data: */
555 len = qword_get(&mesg, buf, mlen);
556 if (len < 0)
557 goto out;
558 status = gss_import_sec_context(buf, len, gm, &rsci.mechctx,
559 NULL, GFP_KERNEL);
560 if (status)
561 goto out;
562
563 /* get client name */
564 len = qword_get(&mesg, buf, mlen);
565 if (len > 0) {
566 rsci.cred.cr_principal = kstrdup(buf, GFP_KERNEL);
567 if (!rsci.cred.cr_principal) {
568 status = -ENOMEM;
569 goto out;
570 }
571 }
572
573 }
574 rsci.h.expiry_time = expiry;
575 rscp = rsc_update(cd, &rsci, rscp);
576 status = 0;
577out:
578 rsc_free(&rsci);
579 if (rscp)
580 cache_put(&rscp->h, cd);
581 else
582 status = -ENOMEM;
583 return status;
584}
585
586static const struct cache_detail rsc_cache_template = {
587 .owner = THIS_MODULE,
588 .hash_size = RSC_HASHMAX,
589 .name = "auth.rpcsec.context",
590 .cache_put = rsc_put,
591 .cache_upcall = rsc_upcall,
592 .cache_parse = rsc_parse,
593 .match = rsc_match,
594 .init = rsc_init,
595 .update = update_rsc,
596 .alloc = rsc_alloc,
597};
598
599static struct rsc *rsc_lookup(struct cache_detail *cd, struct rsc *item)
600{
601 struct cache_head *ch;
602 int hash = rsc_hash(item);
603
604 ch = sunrpc_cache_lookup_rcu(cd, &item->h, hash);
605 if (ch)
606 return container_of(ch, struct rsc, h);
607 else
608 return NULL;
609}
610
611static struct rsc *rsc_update(struct cache_detail *cd, struct rsc *new, struct rsc *old)
612{
613 struct cache_head *ch;
614 int hash = rsc_hash(new);
615
616 ch = sunrpc_cache_update(cd, &new->h,
617 &old->h, hash);
618 if (ch)
619 return container_of(ch, struct rsc, h);
620 else
621 return NULL;
622}
623
624
625static struct rsc *
626gss_svc_searchbyctx(struct cache_detail *cd, struct xdr_netobj *handle)
627{
628 struct rsc rsci;
629 struct rsc *found;
630
631 memset(&rsci, 0, sizeof(rsci));
632 if (dup_to_netobj(&rsci.handle, handle->data, handle->len))
633 return NULL;
634 found = rsc_lookup(cd, &rsci);
635 rsc_free(&rsci);
636 if (!found)
637 return NULL;
638 if (cache_check(cd, &found->h, NULL))
639 return NULL;
640 return found;
641}
642
643/**
644 * gss_check_seq_num - GSS sequence number window check
645 * @rqstp: RPC Call to use when reporting errors
646 * @rsci: cached GSS context state (updated on return)
647 * @seq_num: sequence number to check
648 *
649 * Implements sequence number algorithm as specified in
650 * RFC 2203, Section 5.3.3.1. "Context Management".
651 *
652 * Return values:
653 * %true: @rqstp's GSS sequence number is inside the window
654 * %false: @rqstp's GSS sequence number is outside the window
655 */
656static bool gss_check_seq_num(const struct svc_rqst *rqstp, struct rsc *rsci,
657 u32 seq_num)
658{
659 struct gss_svc_seq_data *sd = &rsci->seqdata;
660 bool result = false;
661
662 spin_lock(&sd->sd_lock);
663 if (seq_num > sd->sd_max) {
664 if (seq_num >= sd->sd_max + GSS_SEQ_WIN) {
665 memset(sd->sd_win, 0, sizeof(sd->sd_win));
666 sd->sd_max = seq_num;
667 } else while (sd->sd_max < seq_num) {
668 sd->sd_max++;
669 __clear_bit(sd->sd_max % GSS_SEQ_WIN, sd->sd_win);
670 }
671 __set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win);
672 goto ok;
673 } else if (seq_num + GSS_SEQ_WIN <= sd->sd_max) {
674 goto toolow;
675 }
676 if (__test_and_set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win))
677 goto alreadyseen;
678
679ok:
680 result = true;
681out:
682 spin_unlock(&sd->sd_lock);
683 return result;
684
685toolow:
686 trace_rpcgss_svc_seqno_low(rqstp, seq_num,
687 sd->sd_max - GSS_SEQ_WIN,
688 sd->sd_max);
689 goto out;
690alreadyseen:
691 trace_rpcgss_svc_seqno_seen(rqstp, seq_num);
692 goto out;
693}
694
695static inline u32 round_up_to_quad(u32 i)
696{
697 return (i + 3 ) & ~3;
698}
699
700static inline int
701svc_safe_getnetobj(struct kvec *argv, struct xdr_netobj *o)
702{
703 int l;
704
705 if (argv->iov_len < 4)
706 return -1;
707 o->len = svc_getnl(argv);
708 l = round_up_to_quad(o->len);
709 if (argv->iov_len < l)
710 return -1;
711 o->data = argv->iov_base;
712 argv->iov_base += l;
713 argv->iov_len -= l;
714 return 0;
715}
716
717static inline int
718svc_safe_putnetobj(struct kvec *resv, struct xdr_netobj *o)
719{
720 u8 *p;
721
722 if (resv->iov_len + 4 > PAGE_SIZE)
723 return -1;
724 svc_putnl(resv, o->len);
725 p = resv->iov_base + resv->iov_len;
726 resv->iov_len += round_up_to_quad(o->len);
727 if (resv->iov_len > PAGE_SIZE)
728 return -1;
729 memcpy(p, o->data, o->len);
730 memset(p + o->len, 0, round_up_to_quad(o->len) - o->len);
731 return 0;
732}
733
734/*
735 * Verify the checksum on the header and return SVC_OK on success.
736 * Otherwise, return SVC_DROP (in the case of a bad sequence number)
737 * or return SVC_DENIED and indicate error in rqstp->rq_auth_stat.
738 */
739static int
740gss_verify_header(struct svc_rqst *rqstp, struct rsc *rsci,
741 __be32 *rpcstart, struct rpc_gss_wire_cred *gc)
742{
743 struct gss_ctx *ctx_id = rsci->mechctx;
744 struct xdr_buf rpchdr;
745 struct xdr_netobj checksum;
746 u32 flavor = 0;
747 struct kvec *argv = &rqstp->rq_arg.head[0];
748 struct kvec iov;
749
750 /* data to compute the checksum over: */
751 iov.iov_base = rpcstart;
752 iov.iov_len = (u8 *)argv->iov_base - (u8 *)rpcstart;
753 xdr_buf_from_iov(&iov, &rpchdr);
754
755 rqstp->rq_auth_stat = rpc_autherr_badverf;
756 if (argv->iov_len < 4)
757 return SVC_DENIED;
758 flavor = svc_getnl(argv);
759 if (flavor != RPC_AUTH_GSS)
760 return SVC_DENIED;
761 if (svc_safe_getnetobj(argv, &checksum))
762 return SVC_DENIED;
763
764 if (rqstp->rq_deferred) /* skip verification of revisited request */
765 return SVC_OK;
766 if (gss_verify_mic(ctx_id, &rpchdr, &checksum) != GSS_S_COMPLETE) {
767 rqstp->rq_auth_stat = rpcsec_gsserr_credproblem;
768 return SVC_DENIED;
769 }
770
771 if (gc->gc_seq > MAXSEQ) {
772 trace_rpcgss_svc_seqno_large(rqstp, gc->gc_seq);
773 rqstp->rq_auth_stat = rpcsec_gsserr_ctxproblem;
774 return SVC_DENIED;
775 }
776 if (!gss_check_seq_num(rqstp, rsci, gc->gc_seq))
777 return SVC_DROP;
778 return SVC_OK;
779}
780
781static int
782gss_write_null_verf(struct svc_rqst *rqstp)
783{
784 __be32 *p;
785
786 svc_putnl(rqstp->rq_res.head, RPC_AUTH_NULL);
787 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len;
788 /* don't really need to check if head->iov_len > PAGE_SIZE ... */
789 *p++ = 0;
790 if (!xdr_ressize_check(rqstp, p))
791 return -1;
792 return 0;
793}
794
795static int
796gss_write_verf(struct svc_rqst *rqstp, struct gss_ctx *ctx_id, u32 seq)
797{
798 __be32 *xdr_seq;
799 u32 maj_stat;
800 struct xdr_buf verf_data;
801 struct xdr_netobj mic;
802 __be32 *p;
803 struct kvec iov;
804 int err = -1;
805
806 svc_putnl(rqstp->rq_res.head, RPC_AUTH_GSS);
807 xdr_seq = kmalloc(4, GFP_KERNEL);
808 if (!xdr_seq)
809 return -ENOMEM;
810 *xdr_seq = htonl(seq);
811
812 iov.iov_base = xdr_seq;
813 iov.iov_len = 4;
814 xdr_buf_from_iov(&iov, &verf_data);
815 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len;
816 mic.data = (u8 *)(p + 1);
817 maj_stat = gss_get_mic(ctx_id, &verf_data, &mic);
818 if (maj_stat != GSS_S_COMPLETE)
819 goto out;
820 *p++ = htonl(mic.len);
821 memset((u8 *)p + mic.len, 0, round_up_to_quad(mic.len) - mic.len);
822 p += XDR_QUADLEN(mic.len);
823 if (!xdr_ressize_check(rqstp, p))
824 goto out;
825 err = 0;
826out:
827 kfree(xdr_seq);
828 return err;
829}
830
831struct gss_domain {
832 struct auth_domain h;
833 u32 pseudoflavor;
834};
835
836static struct auth_domain *
837find_gss_auth_domain(struct gss_ctx *ctx, u32 svc)
838{
839 char *name;
840
841 name = gss_service_to_auth_domain_name(ctx->mech_type, svc);
842 if (!name)
843 return NULL;
844 return auth_domain_find(name);
845}
846
847static struct auth_ops svcauthops_gss;
848
849u32 svcauth_gss_flavor(struct auth_domain *dom)
850{
851 struct gss_domain *gd = container_of(dom, struct gss_domain, h);
852
853 return gd->pseudoflavor;
854}
855
856EXPORT_SYMBOL_GPL(svcauth_gss_flavor);
857
858struct auth_domain *
859svcauth_gss_register_pseudoflavor(u32 pseudoflavor, char * name)
860{
861 struct gss_domain *new;
862 struct auth_domain *test;
863 int stat = -ENOMEM;
864
865 new = kmalloc(sizeof(*new), GFP_KERNEL);
866 if (!new)
867 goto out;
868 kref_init(&new->h.ref);
869 new->h.name = kstrdup(name, GFP_KERNEL);
870 if (!new->h.name)
871 goto out_free_dom;
872 new->h.flavour = &svcauthops_gss;
873 new->pseudoflavor = pseudoflavor;
874
875 test = auth_domain_lookup(name, &new->h);
876 if (test != &new->h) {
877 pr_warn("svc: duplicate registration of gss pseudo flavour %s.\n",
878 name);
879 stat = -EADDRINUSE;
880 auth_domain_put(test);
881 goto out_free_name;
882 }
883 return test;
884
885out_free_name:
886 kfree(new->h.name);
887out_free_dom:
888 kfree(new);
889out:
890 return ERR_PTR(stat);
891}
892EXPORT_SYMBOL_GPL(svcauth_gss_register_pseudoflavor);
893
894static inline int
895read_u32_from_xdr_buf(struct xdr_buf *buf, int base, u32 *obj)
896{
897 __be32 raw;
898 int status;
899
900 status = read_bytes_from_xdr_buf(buf, base, &raw, sizeof(*obj));
901 if (status)
902 return status;
903 *obj = ntohl(raw);
904 return 0;
905}
906
907/* It would be nice if this bit of code could be shared with the client.
908 * Obstacles:
909 * The client shouldn't malloc(), would have to pass in own memory.
910 * The server uses base of head iovec as read pointer, while the
911 * client uses separate pointer. */
912static int
913unwrap_integ_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx)
914{
915 struct gss_svc_data *gsd = rqstp->rq_auth_data;
916 u32 integ_len, rseqno, maj_stat;
917 struct xdr_netobj mic;
918 struct xdr_buf integ_buf;
919
920 /* NFS READ normally uses splice to send data in-place. However
921 * the data in cache can change after the reply's MIC is computed
922 * but before the RPC reply is sent. To prevent the client from
923 * rejecting the server-computed MIC in this somewhat rare case,
924 * do not use splice with the GSS integrity service.
925 */
926 clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
927
928 /* Did we already verify the signature on the original pass through? */
929 if (rqstp->rq_deferred)
930 return 0;
931
932 integ_len = svc_getnl(&buf->head[0]);
933 if (integ_len & 3)
934 goto unwrap_failed;
935 if (integ_len > buf->len)
936 goto unwrap_failed;
937 if (xdr_buf_subsegment(buf, &integ_buf, 0, integ_len))
938 goto unwrap_failed;
939
940 /* copy out mic... */
941 if (read_u32_from_xdr_buf(buf, integ_len, &mic.len))
942 goto unwrap_failed;
943 if (mic.len > sizeof(gsd->gsd_scratch))
944 goto unwrap_failed;
945 mic.data = gsd->gsd_scratch;
946 if (read_bytes_from_xdr_buf(buf, integ_len + 4, mic.data, mic.len))
947 goto unwrap_failed;
948 maj_stat = gss_verify_mic(ctx, &integ_buf, &mic);
949 if (maj_stat != GSS_S_COMPLETE)
950 goto bad_mic;
951 rseqno = svc_getnl(&buf->head[0]);
952 if (rseqno != seq)
953 goto bad_seqno;
954 /* trim off the mic and padding at the end before returning */
955 xdr_buf_trim(buf, round_up_to_quad(mic.len) + 4);
956 return 0;
957
958unwrap_failed:
959 trace_rpcgss_svc_unwrap_failed(rqstp);
960 return -EINVAL;
961bad_seqno:
962 trace_rpcgss_svc_seqno_bad(rqstp, seq, rseqno);
963 return -EINVAL;
964bad_mic:
965 trace_rpcgss_svc_mic(rqstp, maj_stat);
966 return -EINVAL;
967}
968
969static inline int
970total_buf_len(struct xdr_buf *buf)
971{
972 return buf->head[0].iov_len + buf->page_len + buf->tail[0].iov_len;
973}
974
975static void
976fix_priv_head(struct xdr_buf *buf, int pad)
977{
978 if (buf->page_len == 0) {
979 /* We need to adjust head and buf->len in tandem in this
980 * case to make svc_defer() work--it finds the original
981 * buffer start using buf->len - buf->head[0].iov_len. */
982 buf->head[0].iov_len -= pad;
983 }
984}
985
986static int
987unwrap_priv_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx)
988{
989 u32 priv_len, maj_stat;
990 int pad, remaining_len, offset;
991 u32 rseqno;
992
993 clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
994
995 priv_len = svc_getnl(&buf->head[0]);
996 if (rqstp->rq_deferred) {
997 /* Already decrypted last time through! The sequence number
998 * check at out_seq is unnecessary but harmless: */
999 goto out_seq;
1000 }
1001 /* buf->len is the number of bytes from the original start of the
1002 * request to the end, where head[0].iov_len is just the bytes
1003 * not yet read from the head, so these two values are different: */
1004 remaining_len = total_buf_len(buf);
1005 if (priv_len > remaining_len)
1006 goto unwrap_failed;
1007 pad = remaining_len - priv_len;
1008 buf->len -= pad;
1009 fix_priv_head(buf, pad);
1010
1011 maj_stat = gss_unwrap(ctx, 0, priv_len, buf);
1012 pad = priv_len - buf->len;
1013 /* The upper layers assume the buffer is aligned on 4-byte boundaries.
1014 * In the krb5p case, at least, the data ends up offset, so we need to
1015 * move it around. */
1016 /* XXX: This is very inefficient. It would be better to either do
1017 * this while we encrypt, or maybe in the receive code, if we can peak
1018 * ahead and work out the service and mechanism there. */
1019 offset = xdr_pad_size(buf->head[0].iov_len);
1020 if (offset) {
1021 buf->buflen = RPCSVC_MAXPAYLOAD;
1022 xdr_shift_buf(buf, offset);
1023 fix_priv_head(buf, pad);
1024 }
1025 if (maj_stat != GSS_S_COMPLETE)
1026 goto bad_unwrap;
1027out_seq:
1028 rseqno = svc_getnl(&buf->head[0]);
1029 if (rseqno != seq)
1030 goto bad_seqno;
1031 return 0;
1032
1033unwrap_failed:
1034 trace_rpcgss_svc_unwrap_failed(rqstp);
1035 return -EINVAL;
1036bad_seqno:
1037 trace_rpcgss_svc_seqno_bad(rqstp, seq, rseqno);
1038 return -EINVAL;
1039bad_unwrap:
1040 trace_rpcgss_svc_unwrap(rqstp, maj_stat);
1041 return -EINVAL;
1042}
1043
1044static int
1045svcauth_gss_set_client(struct svc_rqst *rqstp)
1046{
1047 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
1048 struct rsc *rsci = svcdata->rsci;
1049 struct rpc_gss_wire_cred *gc = &svcdata->clcred;
1050 int stat;
1051
1052 rqstp->rq_auth_stat = rpc_autherr_badcred;
1053
1054 /*
1055 * A gss export can be specified either by:
1056 * export *(sec=krb5,rw)
1057 * or by
1058 * export gss/krb5(rw)
1059 * The latter is deprecated; but for backwards compatibility reasons
1060 * the nfsd code will still fall back on trying it if the former
1061 * doesn't work; so we try to make both available to nfsd, below.
1062 */
1063 rqstp->rq_gssclient = find_gss_auth_domain(rsci->mechctx, gc->gc_svc);
1064 if (rqstp->rq_gssclient == NULL)
1065 return SVC_DENIED;
1066 stat = svcauth_unix_set_client(rqstp);
1067 if (stat == SVC_DROP || stat == SVC_CLOSE)
1068 return stat;
1069
1070 rqstp->rq_auth_stat = rpc_auth_ok;
1071 return SVC_OK;
1072}
1073
1074static inline int
1075gss_write_init_verf(struct cache_detail *cd, struct svc_rqst *rqstp,
1076 struct xdr_netobj *out_handle, int *major_status)
1077{
1078 struct rsc *rsci;
1079 int rc;
1080
1081 if (*major_status != GSS_S_COMPLETE)
1082 return gss_write_null_verf(rqstp);
1083 rsci = gss_svc_searchbyctx(cd, out_handle);
1084 if (rsci == NULL) {
1085 *major_status = GSS_S_NO_CONTEXT;
1086 return gss_write_null_verf(rqstp);
1087 }
1088 rc = gss_write_verf(rqstp, rsci->mechctx, GSS_SEQ_WIN);
1089 cache_put(&rsci->h, cd);
1090 return rc;
1091}
1092
1093static inline int
1094gss_read_common_verf(struct rpc_gss_wire_cred *gc,
1095 struct kvec *argv, __be32 *authp,
1096 struct xdr_netobj *in_handle)
1097{
1098 /* Read the verifier; should be NULL: */
1099 *authp = rpc_autherr_badverf;
1100 if (argv->iov_len < 2 * 4)
1101 return SVC_DENIED;
1102 if (svc_getnl(argv) != RPC_AUTH_NULL)
1103 return SVC_DENIED;
1104 if (svc_getnl(argv) != 0)
1105 return SVC_DENIED;
1106 /* Martial context handle and token for upcall: */
1107 *authp = rpc_autherr_badcred;
1108 if (gc->gc_proc == RPC_GSS_PROC_INIT && gc->gc_ctx.len != 0)
1109 return SVC_DENIED;
1110 if (dup_netobj(in_handle, &gc->gc_ctx))
1111 return SVC_CLOSE;
1112 *authp = rpc_autherr_badverf;
1113
1114 return 0;
1115}
1116
1117static inline int
1118gss_read_verf(struct rpc_gss_wire_cred *gc,
1119 struct kvec *argv, __be32 *authp,
1120 struct xdr_netobj *in_handle,
1121 struct xdr_netobj *in_token)
1122{
1123 struct xdr_netobj tmpobj;
1124 int res;
1125
1126 res = gss_read_common_verf(gc, argv, authp, in_handle);
1127 if (res)
1128 return res;
1129
1130 if (svc_safe_getnetobj(argv, &tmpobj)) {
1131 kfree(in_handle->data);
1132 return SVC_DENIED;
1133 }
1134 if (dup_netobj(in_token, &tmpobj)) {
1135 kfree(in_handle->data);
1136 return SVC_CLOSE;
1137 }
1138
1139 return 0;
1140}
1141
1142static void gss_free_in_token_pages(struct gssp_in_token *in_token)
1143{
1144 u32 inlen;
1145 int i;
1146
1147 i = 0;
1148 inlen = in_token->page_len;
1149 while (inlen) {
1150 if (in_token->pages[i])
1151 put_page(in_token->pages[i]);
1152 inlen -= inlen > PAGE_SIZE ? PAGE_SIZE : inlen;
1153 }
1154
1155 kfree(in_token->pages);
1156 in_token->pages = NULL;
1157}
1158
1159static int gss_read_proxy_verf(struct svc_rqst *rqstp,
1160 struct rpc_gss_wire_cred *gc,
1161 struct xdr_netobj *in_handle,
1162 struct gssp_in_token *in_token)
1163{
1164 struct kvec *argv = &rqstp->rq_arg.head[0];
1165 unsigned int length, pgto_offs, pgfrom_offs;
1166 int pages, i, res, pgto, pgfrom;
1167 size_t inlen, to_offs, from_offs;
1168
1169 res = gss_read_common_verf(gc, argv, &rqstp->rq_auth_stat, in_handle);
1170 if (res)
1171 return res;
1172
1173 inlen = svc_getnl(argv);
1174 if (inlen > (argv->iov_len + rqstp->rq_arg.page_len)) {
1175 kfree(in_handle->data);
1176 return SVC_DENIED;
1177 }
1178
1179 pages = DIV_ROUND_UP(inlen, PAGE_SIZE);
1180 in_token->pages = kcalloc(pages, sizeof(struct page *), GFP_KERNEL);
1181 if (!in_token->pages) {
1182 kfree(in_handle->data);
1183 return SVC_DENIED;
1184 }
1185 in_token->page_base = 0;
1186 in_token->page_len = inlen;
1187 for (i = 0; i < pages; i++) {
1188 in_token->pages[i] = alloc_page(GFP_KERNEL);
1189 if (!in_token->pages[i]) {
1190 kfree(in_handle->data);
1191 gss_free_in_token_pages(in_token);
1192 return SVC_DENIED;
1193 }
1194 }
1195
1196 length = min_t(unsigned int, inlen, argv->iov_len);
1197 memcpy(page_address(in_token->pages[0]), argv->iov_base, length);
1198 inlen -= length;
1199
1200 to_offs = length;
1201 from_offs = rqstp->rq_arg.page_base;
1202 while (inlen) {
1203 pgto = to_offs >> PAGE_SHIFT;
1204 pgfrom = from_offs >> PAGE_SHIFT;
1205 pgto_offs = to_offs & ~PAGE_MASK;
1206 pgfrom_offs = from_offs & ~PAGE_MASK;
1207
1208 length = min_t(unsigned int, inlen,
1209 min_t(unsigned int, PAGE_SIZE - pgto_offs,
1210 PAGE_SIZE - pgfrom_offs));
1211 memcpy(page_address(in_token->pages[pgto]) + pgto_offs,
1212 page_address(rqstp->rq_arg.pages[pgfrom]) + pgfrom_offs,
1213 length);
1214
1215 to_offs += length;
1216 from_offs += length;
1217 inlen -= length;
1218 }
1219 return 0;
1220}
1221
1222static inline int
1223gss_write_resv(struct kvec *resv, size_t size_limit,
1224 struct xdr_netobj *out_handle, struct xdr_netobj *out_token,
1225 int major_status, int minor_status)
1226{
1227 if (resv->iov_len + 4 > size_limit)
1228 return -1;
1229 svc_putnl(resv, RPC_SUCCESS);
1230 if (svc_safe_putnetobj(resv, out_handle))
1231 return -1;
1232 if (resv->iov_len + 3 * 4 > size_limit)
1233 return -1;
1234 svc_putnl(resv, major_status);
1235 svc_putnl(resv, minor_status);
1236 svc_putnl(resv, GSS_SEQ_WIN);
1237 if (svc_safe_putnetobj(resv, out_token))
1238 return -1;
1239 return 0;
1240}
1241
1242/*
1243 * Having read the cred already and found we're in the context
1244 * initiation case, read the verifier and initiate (or check the results
1245 * of) upcalls to userspace for help with context initiation. If
1246 * the upcall results are available, write the verifier and result.
1247 * Otherwise, drop the request pending an answer to the upcall.
1248 */
1249static int svcauth_gss_legacy_init(struct svc_rqst *rqstp,
1250 struct rpc_gss_wire_cred *gc)
1251{
1252 struct kvec *argv = &rqstp->rq_arg.head[0];
1253 struct kvec *resv = &rqstp->rq_res.head[0];
1254 struct rsi *rsip, rsikey;
1255 int ret;
1256 struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id);
1257
1258 memset(&rsikey, 0, sizeof(rsikey));
1259 ret = gss_read_verf(gc, argv, &rqstp->rq_auth_stat,
1260 &rsikey.in_handle, &rsikey.in_token);
1261 if (ret)
1262 return ret;
1263
1264 /* Perform upcall, or find upcall result: */
1265 rsip = rsi_lookup(sn->rsi_cache, &rsikey);
1266 rsi_free(&rsikey);
1267 if (!rsip)
1268 return SVC_CLOSE;
1269 if (cache_check(sn->rsi_cache, &rsip->h, &rqstp->rq_chandle) < 0)
1270 /* No upcall result: */
1271 return SVC_CLOSE;
1272
1273 ret = SVC_CLOSE;
1274 /* Got an answer to the upcall; use it: */
1275 if (gss_write_init_verf(sn->rsc_cache, rqstp,
1276 &rsip->out_handle, &rsip->major_status))
1277 goto out;
1278 if (gss_write_resv(resv, PAGE_SIZE,
1279 &rsip->out_handle, &rsip->out_token,
1280 rsip->major_status, rsip->minor_status))
1281 goto out;
1282
1283 ret = SVC_COMPLETE;
1284out:
1285 cache_put(&rsip->h, sn->rsi_cache);
1286 return ret;
1287}
1288
1289static int gss_proxy_save_rsc(struct cache_detail *cd,
1290 struct gssp_upcall_data *ud,
1291 uint64_t *handle)
1292{
1293 struct rsc rsci, *rscp = NULL;
1294 static atomic64_t ctxhctr;
1295 long long ctxh;
1296 struct gss_api_mech *gm = NULL;
1297 time64_t expiry;
1298 int status;
1299
1300 memset(&rsci, 0, sizeof(rsci));
1301 /* context handle */
1302 status = -ENOMEM;
1303 /* the handle needs to be just a unique id,
1304 * use a static counter */
1305 ctxh = atomic64_inc_return(&ctxhctr);
1306
1307 /* make a copy for the caller */
1308 *handle = ctxh;
1309
1310 /* make a copy for the rsc cache */
1311 if (dup_to_netobj(&rsci.handle, (char *)handle, sizeof(uint64_t)))
1312 goto out;
1313 rscp = rsc_lookup(cd, &rsci);
1314 if (!rscp)
1315 goto out;
1316
1317 /* creds */
1318 if (!ud->found_creds) {
1319 /* userspace seem buggy, we should always get at least a
1320 * mapping to nobody */
1321 goto out;
1322 } else {
1323 struct timespec64 boot;
1324
1325 /* steal creds */
1326 rsci.cred = ud->creds;
1327 memset(&ud->creds, 0, sizeof(struct svc_cred));
1328
1329 status = -EOPNOTSUPP;
1330 /* get mech handle from OID */
1331 gm = gss_mech_get_by_OID(&ud->mech_oid);
1332 if (!gm)
1333 goto out;
1334 rsci.cred.cr_gss_mech = gm;
1335
1336 status = -EINVAL;
1337 /* mech-specific data: */
1338 status = gss_import_sec_context(ud->out_handle.data,
1339 ud->out_handle.len,
1340 gm, &rsci.mechctx,
1341 &expiry, GFP_KERNEL);
1342 if (status)
1343 goto out;
1344
1345 getboottime64(&boot);
1346 expiry -= boot.tv_sec;
1347 }
1348
1349 rsci.h.expiry_time = expiry;
1350 rscp = rsc_update(cd, &rsci, rscp);
1351 status = 0;
1352out:
1353 rsc_free(&rsci);
1354 if (rscp)
1355 cache_put(&rscp->h, cd);
1356 else
1357 status = -ENOMEM;
1358 return status;
1359}
1360
1361static int svcauth_gss_proxy_init(struct svc_rqst *rqstp,
1362 struct rpc_gss_wire_cred *gc)
1363{
1364 struct kvec *resv = &rqstp->rq_res.head[0];
1365 struct xdr_netobj cli_handle;
1366 struct gssp_upcall_data ud;
1367 uint64_t handle;
1368 int status;
1369 int ret;
1370 struct net *net = SVC_NET(rqstp);
1371 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1372
1373 memset(&ud, 0, sizeof(ud));
1374 ret = gss_read_proxy_verf(rqstp, gc, &ud.in_handle, &ud.in_token);
1375 if (ret)
1376 return ret;
1377
1378 ret = SVC_CLOSE;
1379
1380 /* Perform synchronous upcall to gss-proxy */
1381 status = gssp_accept_sec_context_upcall(net, &ud);
1382 if (status)
1383 goto out;
1384
1385 trace_rpcgss_svc_accept_upcall(rqstp, ud.major_status, ud.minor_status);
1386
1387 switch (ud.major_status) {
1388 case GSS_S_CONTINUE_NEEDED:
1389 cli_handle = ud.out_handle;
1390 break;
1391 case GSS_S_COMPLETE:
1392 status = gss_proxy_save_rsc(sn->rsc_cache, &ud, &handle);
1393 if (status)
1394 goto out;
1395 cli_handle.data = (u8 *)&handle;
1396 cli_handle.len = sizeof(handle);
1397 break;
1398 default:
1399 goto out;
1400 }
1401
1402 /* Got an answer to the upcall; use it: */
1403 if (gss_write_init_verf(sn->rsc_cache, rqstp,
1404 &cli_handle, &ud.major_status))
1405 goto out;
1406 if (gss_write_resv(resv, PAGE_SIZE,
1407 &cli_handle, &ud.out_token,
1408 ud.major_status, ud.minor_status))
1409 goto out;
1410
1411 ret = SVC_COMPLETE;
1412out:
1413 gss_free_in_token_pages(&ud.in_token);
1414 gssp_free_upcall_data(&ud);
1415 return ret;
1416}
1417
1418/*
1419 * Try to set the sn->use_gss_proxy variable to a new value. We only allow
1420 * it to be changed if it's currently undefined (-1). If it's any other value
1421 * then return -EBUSY unless the type wouldn't have changed anyway.
1422 */
1423static int set_gss_proxy(struct net *net, int type)
1424{
1425 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1426 int ret;
1427
1428 WARN_ON_ONCE(type != 0 && type != 1);
1429 ret = cmpxchg(&sn->use_gss_proxy, -1, type);
1430 if (ret != -1 && ret != type)
1431 return -EBUSY;
1432 return 0;
1433}
1434
1435static bool use_gss_proxy(struct net *net)
1436{
1437 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1438
1439 /* If use_gss_proxy is still undefined, then try to disable it */
1440 if (sn->use_gss_proxy == -1)
1441 set_gss_proxy(net, 0);
1442 return sn->use_gss_proxy;
1443}
1444
1445#ifdef CONFIG_PROC_FS
1446
1447static ssize_t write_gssp(struct file *file, const char __user *buf,
1448 size_t count, loff_t *ppos)
1449{
1450 struct net *net = pde_data(file_inode(file));
1451 char tbuf[20];
1452 unsigned long i;
1453 int res;
1454
1455 if (*ppos || count > sizeof(tbuf)-1)
1456 return -EINVAL;
1457 if (copy_from_user(tbuf, buf, count))
1458 return -EFAULT;
1459
1460 tbuf[count] = 0;
1461 res = kstrtoul(tbuf, 0, &i);
1462 if (res)
1463 return res;
1464 if (i != 1)
1465 return -EINVAL;
1466 res = set_gssp_clnt(net);
1467 if (res)
1468 return res;
1469 res = set_gss_proxy(net, 1);
1470 if (res)
1471 return res;
1472 return count;
1473}
1474
1475static ssize_t read_gssp(struct file *file, char __user *buf,
1476 size_t count, loff_t *ppos)
1477{
1478 struct net *net = pde_data(file_inode(file));
1479 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1480 unsigned long p = *ppos;
1481 char tbuf[10];
1482 size_t len;
1483
1484 snprintf(tbuf, sizeof(tbuf), "%d\n", sn->use_gss_proxy);
1485 len = strlen(tbuf);
1486 if (p >= len)
1487 return 0;
1488 len -= p;
1489 if (len > count)
1490 len = count;
1491 if (copy_to_user(buf, (void *)(tbuf+p), len))
1492 return -EFAULT;
1493 *ppos += len;
1494 return len;
1495}
1496
1497static const struct proc_ops use_gss_proxy_proc_ops = {
1498 .proc_open = nonseekable_open,
1499 .proc_write = write_gssp,
1500 .proc_read = read_gssp,
1501};
1502
1503static int create_use_gss_proxy_proc_entry(struct net *net)
1504{
1505 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1506 struct proc_dir_entry **p = &sn->use_gssp_proc;
1507
1508 sn->use_gss_proxy = -1;
1509 *p = proc_create_data("use-gss-proxy", S_IFREG | 0600,
1510 sn->proc_net_rpc,
1511 &use_gss_proxy_proc_ops, net);
1512 if (!*p)
1513 return -ENOMEM;
1514 init_gssp_clnt(sn);
1515 return 0;
1516}
1517
1518static void destroy_use_gss_proxy_proc_entry(struct net *net)
1519{
1520 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1521
1522 if (sn->use_gssp_proc) {
1523 remove_proc_entry("use-gss-proxy", sn->proc_net_rpc);
1524 clear_gssp_clnt(sn);
1525 }
1526}
1527#else /* CONFIG_PROC_FS */
1528
1529static int create_use_gss_proxy_proc_entry(struct net *net)
1530{
1531 return 0;
1532}
1533
1534static void destroy_use_gss_proxy_proc_entry(struct net *net) {}
1535
1536#endif /* CONFIG_PROC_FS */
1537
1538/*
1539 * Accept an rpcsec packet.
1540 * If context establishment, punt to user space
1541 * If data exchange, verify/decrypt
1542 * If context destruction, handle here
1543 * In the context establishment and destruction case we encode
1544 * response here and return SVC_COMPLETE.
1545 */
1546static int
1547svcauth_gss_accept(struct svc_rqst *rqstp)
1548{
1549 struct kvec *argv = &rqstp->rq_arg.head[0];
1550 struct kvec *resv = &rqstp->rq_res.head[0];
1551 u32 crlen;
1552 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
1553 struct rpc_gss_wire_cred *gc;
1554 struct rsc *rsci = NULL;
1555 __be32 *rpcstart;
1556 __be32 *reject_stat = resv->iov_base + resv->iov_len;
1557 int ret;
1558 struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id);
1559
1560 rqstp->rq_auth_stat = rpc_autherr_badcred;
1561 if (!svcdata)
1562 svcdata = kmalloc(sizeof(*svcdata), GFP_KERNEL);
1563 if (!svcdata)
1564 goto auth_err;
1565 rqstp->rq_auth_data = svcdata;
1566 svcdata->verf_start = NULL;
1567 svcdata->rsci = NULL;
1568 gc = &svcdata->clcred;
1569
1570 /* start of rpc packet is 7 u32's back from here:
1571 * xid direction rpcversion prog vers proc flavour
1572 */
1573 rpcstart = argv->iov_base;
1574 rpcstart -= 7;
1575
1576 /* credential is:
1577 * version(==1), proc(0,1,2,3), seq, service (1,2,3), handle
1578 * at least 5 u32s, and is preceded by length, so that makes 6.
1579 */
1580
1581 if (argv->iov_len < 5 * 4)
1582 goto auth_err;
1583 crlen = svc_getnl(argv);
1584 if (svc_getnl(argv) != RPC_GSS_VERSION)
1585 goto auth_err;
1586 gc->gc_proc = svc_getnl(argv);
1587 gc->gc_seq = svc_getnl(argv);
1588 gc->gc_svc = svc_getnl(argv);
1589 if (svc_safe_getnetobj(argv, &gc->gc_ctx))
1590 goto auth_err;
1591 if (crlen != round_up_to_quad(gc->gc_ctx.len) + 5 * 4)
1592 goto auth_err;
1593
1594 if ((gc->gc_proc != RPC_GSS_PROC_DATA) && (rqstp->rq_proc != 0))
1595 goto auth_err;
1596
1597 rqstp->rq_auth_stat = rpc_autherr_badverf;
1598 switch (gc->gc_proc) {
1599 case RPC_GSS_PROC_INIT:
1600 case RPC_GSS_PROC_CONTINUE_INIT:
1601 if (use_gss_proxy(SVC_NET(rqstp)))
1602 return svcauth_gss_proxy_init(rqstp, gc);
1603 else
1604 return svcauth_gss_legacy_init(rqstp, gc);
1605 case RPC_GSS_PROC_DATA:
1606 case RPC_GSS_PROC_DESTROY:
1607 /* Look up the context, and check the verifier: */
1608 rqstp->rq_auth_stat = rpcsec_gsserr_credproblem;
1609 rsci = gss_svc_searchbyctx(sn->rsc_cache, &gc->gc_ctx);
1610 if (!rsci)
1611 goto auth_err;
1612 switch (gss_verify_header(rqstp, rsci, rpcstart, gc)) {
1613 case SVC_OK:
1614 break;
1615 case SVC_DENIED:
1616 goto auth_err;
1617 case SVC_DROP:
1618 goto drop;
1619 }
1620 break;
1621 default:
1622 rqstp->rq_auth_stat = rpc_autherr_rejectedcred;
1623 goto auth_err;
1624 }
1625
1626 /* now act upon the command: */
1627 switch (gc->gc_proc) {
1628 case RPC_GSS_PROC_DESTROY:
1629 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
1630 goto auth_err;
1631 /* Delete the entry from the cache_list and call cache_put */
1632 sunrpc_cache_unhash(sn->rsc_cache, &rsci->h);
1633 if (resv->iov_len + 4 > PAGE_SIZE)
1634 goto drop;
1635 svc_putnl(resv, RPC_SUCCESS);
1636 goto complete;
1637 case RPC_GSS_PROC_DATA:
1638 rqstp->rq_auth_stat = rpcsec_gsserr_ctxproblem;
1639 svcdata->verf_start = resv->iov_base + resv->iov_len;
1640 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
1641 goto auth_err;
1642 rqstp->rq_cred = rsci->cred;
1643 get_group_info(rsci->cred.cr_group_info);
1644 rqstp->rq_auth_stat = rpc_autherr_badcred;
1645 switch (gc->gc_svc) {
1646 case RPC_GSS_SVC_NONE:
1647 break;
1648 case RPC_GSS_SVC_INTEGRITY:
1649 /* placeholders for length and seq. number: */
1650 svc_putnl(resv, 0);
1651 svc_putnl(resv, 0);
1652 if (unwrap_integ_data(rqstp, &rqstp->rq_arg,
1653 gc->gc_seq, rsci->mechctx))
1654 goto garbage_args;
1655 rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE;
1656 break;
1657 case RPC_GSS_SVC_PRIVACY:
1658 /* placeholders for length and seq. number: */
1659 svc_putnl(resv, 0);
1660 svc_putnl(resv, 0);
1661 if (unwrap_priv_data(rqstp, &rqstp->rq_arg,
1662 gc->gc_seq, rsci->mechctx))
1663 goto garbage_args;
1664 rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE * 2;
1665 break;
1666 default:
1667 goto auth_err;
1668 }
1669 svcdata->rsci = rsci;
1670 cache_get(&rsci->h);
1671 rqstp->rq_cred.cr_flavor = gss_svc_to_pseudoflavor(
1672 rsci->mechctx->mech_type,
1673 GSS_C_QOP_DEFAULT,
1674 gc->gc_svc);
1675 ret = SVC_OK;
1676 trace_rpcgss_svc_authenticate(rqstp, gc);
1677 goto out;
1678 }
1679garbage_args:
1680 ret = SVC_GARBAGE;
1681 goto out;
1682auth_err:
1683 /* Restore write pointer to its original value: */
1684 xdr_ressize_check(rqstp, reject_stat);
1685 ret = SVC_DENIED;
1686 goto out;
1687complete:
1688 ret = SVC_COMPLETE;
1689 goto out;
1690drop:
1691 ret = SVC_CLOSE;
1692out:
1693 if (rsci)
1694 cache_put(&rsci->h, sn->rsc_cache);
1695 return ret;
1696}
1697
1698static __be32 *
1699svcauth_gss_prepare_to_wrap(struct xdr_buf *resbuf, struct gss_svc_data *gsd)
1700{
1701 __be32 *p;
1702 u32 verf_len;
1703
1704 p = gsd->verf_start;
1705 gsd->verf_start = NULL;
1706
1707 /* If the reply stat is nonzero, don't wrap: */
1708 if (*(p-1) != rpc_success)
1709 return NULL;
1710 /* Skip the verifier: */
1711 p += 1;
1712 verf_len = ntohl(*p++);
1713 p += XDR_QUADLEN(verf_len);
1714 /* move accept_stat to right place: */
1715 memcpy(p, p + 2, 4);
1716 /* Also don't wrap if the accept stat is nonzero: */
1717 if (*p != rpc_success) {
1718 resbuf->head[0].iov_len -= 2 * 4;
1719 return NULL;
1720 }
1721 p++;
1722 return p;
1723}
1724
1725static inline int
1726svcauth_gss_wrap_resp_integ(struct svc_rqst *rqstp)
1727{
1728 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1729 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1730 struct xdr_buf *resbuf = &rqstp->rq_res;
1731 struct xdr_buf integ_buf;
1732 struct xdr_netobj mic;
1733 struct kvec *resv;
1734 __be32 *p;
1735 int integ_offset, integ_len;
1736 int stat = -EINVAL;
1737
1738 p = svcauth_gss_prepare_to_wrap(resbuf, gsd);
1739 if (p == NULL)
1740 goto out;
1741 integ_offset = (u8 *)(p + 1) - (u8 *)resbuf->head[0].iov_base;
1742 integ_len = resbuf->len - integ_offset;
1743 if (integ_len & 3)
1744 goto out;
1745 *p++ = htonl(integ_len);
1746 *p++ = htonl(gc->gc_seq);
1747 if (xdr_buf_subsegment(resbuf, &integ_buf, integ_offset, integ_len)) {
1748 WARN_ON_ONCE(1);
1749 goto out_err;
1750 }
1751 if (resbuf->tail[0].iov_base == NULL) {
1752 if (resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1753 goto out_err;
1754 resbuf->tail[0].iov_base = resbuf->head[0].iov_base
1755 + resbuf->head[0].iov_len;
1756 resbuf->tail[0].iov_len = 0;
1757 }
1758 resv = &resbuf->tail[0];
1759 mic.data = (u8 *)resv->iov_base + resv->iov_len + 4;
1760 if (gss_get_mic(gsd->rsci->mechctx, &integ_buf, &mic))
1761 goto out_err;
1762 svc_putnl(resv, mic.len);
1763 memset(mic.data + mic.len, 0,
1764 round_up_to_quad(mic.len) - mic.len);
1765 resv->iov_len += XDR_QUADLEN(mic.len) << 2;
1766 /* not strictly required: */
1767 resbuf->len += XDR_QUADLEN(mic.len) << 2;
1768 if (resv->iov_len > PAGE_SIZE)
1769 goto out_err;
1770out:
1771 stat = 0;
1772out_err:
1773 return stat;
1774}
1775
1776static inline int
1777svcauth_gss_wrap_resp_priv(struct svc_rqst *rqstp)
1778{
1779 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1780 struct rpc_gss_wire_cred *gc = &gsd->clcred;
1781 struct xdr_buf *resbuf = &rqstp->rq_res;
1782 struct page **inpages = NULL;
1783 __be32 *p, *len;
1784 int offset;
1785 int pad;
1786
1787 p = svcauth_gss_prepare_to_wrap(resbuf, gsd);
1788 if (p == NULL)
1789 return 0;
1790 len = p++;
1791 offset = (u8 *)p - (u8 *)resbuf->head[0].iov_base;
1792 *p++ = htonl(gc->gc_seq);
1793 inpages = resbuf->pages;
1794 /* XXX: Would be better to write some xdr helper functions for
1795 * nfs{2,3,4}xdr.c that place the data right, instead of copying: */
1796
1797 /*
1798 * If there is currently tail data, make sure there is
1799 * room for the head, tail, and 2 * RPC_MAX_AUTH_SIZE in
1800 * the page, and move the current tail data such that
1801 * there is RPC_MAX_AUTH_SIZE slack space available in
1802 * both the head and tail.
1803 */
1804 if (resbuf->tail[0].iov_base) {
1805 if (resbuf->tail[0].iov_base >=
1806 resbuf->head[0].iov_base + PAGE_SIZE)
1807 return -EINVAL;
1808 if (resbuf->tail[0].iov_base < resbuf->head[0].iov_base)
1809 return -EINVAL;
1810 if (resbuf->tail[0].iov_len + resbuf->head[0].iov_len
1811 + 2 * RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1812 return -ENOMEM;
1813 memmove(resbuf->tail[0].iov_base + RPC_MAX_AUTH_SIZE,
1814 resbuf->tail[0].iov_base,
1815 resbuf->tail[0].iov_len);
1816 resbuf->tail[0].iov_base += RPC_MAX_AUTH_SIZE;
1817 }
1818 /*
1819 * If there is no current tail data, make sure there is
1820 * room for the head data, and 2 * RPC_MAX_AUTH_SIZE in the
1821 * allotted page, and set up tail information such that there
1822 * is RPC_MAX_AUTH_SIZE slack space available in both the
1823 * head and tail.
1824 */
1825 if (resbuf->tail[0].iov_base == NULL) {
1826 if (resbuf->head[0].iov_len + 2*RPC_MAX_AUTH_SIZE > PAGE_SIZE)
1827 return -ENOMEM;
1828 resbuf->tail[0].iov_base = resbuf->head[0].iov_base
1829 + resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE;
1830 resbuf->tail[0].iov_len = 0;
1831 }
1832 if (gss_wrap(gsd->rsci->mechctx, offset, resbuf, inpages))
1833 return -ENOMEM;
1834 *len = htonl(resbuf->len - offset);
1835 pad = 3 - ((resbuf->len - offset - 1)&3);
1836 p = (__be32 *)(resbuf->tail[0].iov_base + resbuf->tail[0].iov_len);
1837 memset(p, 0, pad);
1838 resbuf->tail[0].iov_len += pad;
1839 resbuf->len += pad;
1840 return 0;
1841}
1842
1843static int
1844svcauth_gss_release(struct svc_rqst *rqstp)
1845{
1846 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
1847 struct rpc_gss_wire_cred *gc;
1848 struct xdr_buf *resbuf = &rqstp->rq_res;
1849 int stat = -EINVAL;
1850 struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id);
1851
1852 if (!gsd)
1853 goto out;
1854 gc = &gsd->clcred;
1855 if (gc->gc_proc != RPC_GSS_PROC_DATA)
1856 goto out;
1857 /* Release can be called twice, but we only wrap once. */
1858 if (gsd->verf_start == NULL)
1859 goto out;
1860 /* normally not set till svc_send, but we need it here: */
1861 /* XXX: what for? Do we mess it up the moment we call svc_putu32
1862 * or whatever? */
1863 resbuf->len = total_buf_len(resbuf);
1864 switch (gc->gc_svc) {
1865 case RPC_GSS_SVC_NONE:
1866 break;
1867 case RPC_GSS_SVC_INTEGRITY:
1868 stat = svcauth_gss_wrap_resp_integ(rqstp);
1869 if (stat)
1870 goto out_err;
1871 break;
1872 case RPC_GSS_SVC_PRIVACY:
1873 stat = svcauth_gss_wrap_resp_priv(rqstp);
1874 if (stat)
1875 goto out_err;
1876 break;
1877 /*
1878 * For any other gc_svc value, svcauth_gss_accept() already set
1879 * the auth_error appropriately; just fall through:
1880 */
1881 }
1882
1883out:
1884 stat = 0;
1885out_err:
1886 if (rqstp->rq_client)
1887 auth_domain_put(rqstp->rq_client);
1888 rqstp->rq_client = NULL;
1889 if (rqstp->rq_gssclient)
1890 auth_domain_put(rqstp->rq_gssclient);
1891 rqstp->rq_gssclient = NULL;
1892 if (rqstp->rq_cred.cr_group_info)
1893 put_group_info(rqstp->rq_cred.cr_group_info);
1894 rqstp->rq_cred.cr_group_info = NULL;
1895 if (gsd && gsd->rsci) {
1896 cache_put(&gsd->rsci->h, sn->rsc_cache);
1897 gsd->rsci = NULL;
1898 }
1899 return stat;
1900}
1901
1902static void
1903svcauth_gss_domain_release_rcu(struct rcu_head *head)
1904{
1905 struct auth_domain *dom = container_of(head, struct auth_domain, rcu_head);
1906 struct gss_domain *gd = container_of(dom, struct gss_domain, h);
1907
1908 kfree(dom->name);
1909 kfree(gd);
1910}
1911
1912static void
1913svcauth_gss_domain_release(struct auth_domain *dom)
1914{
1915 call_rcu(&dom->rcu_head, svcauth_gss_domain_release_rcu);
1916}
1917
1918static struct auth_ops svcauthops_gss = {
1919 .name = "rpcsec_gss",
1920 .owner = THIS_MODULE,
1921 .flavour = RPC_AUTH_GSS,
1922 .accept = svcauth_gss_accept,
1923 .release = svcauth_gss_release,
1924 .domain_release = svcauth_gss_domain_release,
1925 .set_client = svcauth_gss_set_client,
1926};
1927
1928static int rsi_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(&rsi_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->rsi_cache = cd;
1943 return 0;
1944}
1945
1946static void rsi_cache_destroy_net(struct net *net)
1947{
1948 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1949 struct cache_detail *cd = sn->rsi_cache;
1950
1951 sn->rsi_cache = NULL;
1952 cache_purge(cd);
1953 cache_unregister_net(cd, net);
1954 cache_destroy_net(cd, net);
1955}
1956
1957static int rsc_cache_create_net(struct net *net)
1958{
1959 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1960 struct cache_detail *cd;
1961 int err;
1962
1963 cd = cache_create_net(&rsc_cache_template, net);
1964 if (IS_ERR(cd))
1965 return PTR_ERR(cd);
1966 err = cache_register_net(cd, net);
1967 if (err) {
1968 cache_destroy_net(cd, net);
1969 return err;
1970 }
1971 sn->rsc_cache = cd;
1972 return 0;
1973}
1974
1975static void rsc_cache_destroy_net(struct net *net)
1976{
1977 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1978 struct cache_detail *cd = sn->rsc_cache;
1979
1980 sn->rsc_cache = NULL;
1981 cache_purge(cd);
1982 cache_unregister_net(cd, net);
1983 cache_destroy_net(cd, net);
1984}
1985
1986int
1987gss_svc_init_net(struct net *net)
1988{
1989 int rv;
1990
1991 rv = rsc_cache_create_net(net);
1992 if (rv)
1993 return rv;
1994 rv = rsi_cache_create_net(net);
1995 if (rv)
1996 goto out1;
1997 rv = create_use_gss_proxy_proc_entry(net);
1998 if (rv)
1999 goto out2;
2000 return 0;
2001out2:
2002 rsi_cache_destroy_net(net);
2003out1:
2004 rsc_cache_destroy_net(net);
2005 return rv;
2006}
2007
2008void
2009gss_svc_shutdown_net(struct net *net)
2010{
2011 destroy_use_gss_proxy_proc_entry(net);
2012 rsi_cache_destroy_net(net);
2013 rsc_cache_destroy_net(net);
2014}
2015
2016int
2017gss_svc_init(void)
2018{
2019 return svc_auth_register(RPC_AUTH_GSS, &svcauthops_gss);
2020}
2021
2022void
2023gss_svc_shutdown(void)
2024{
2025 svc_auth_unregister(RPC_AUTH_GSS);
2026}
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}