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