blob: 23632d84d8d7c105c2e61cf37a33e11c2e140fe5 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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/types.h>
41#include <linux/module.h>
42#include <linux/pagemap.h>
43
44#include <linux/sunrpc/auth_gss.h>
45#include <linux/sunrpc/svcauth.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#define RSI_HASHMASK (RSI_HASHMAX-1)
71
72struct rsi {
73 struct cache_head h;
74 struct xdr_netobj in_handle, in_token;
75 struct xdr_netobj out_handle, out_token;
76 int major_status, minor_status;
77};
78
79static struct cache_head *rsi_table[RSI_HASHMAX];
80static struct cache_detail rsi_cache;
81static struct rsi *rsi_lookup(struct rsi *item, int set);
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 cache_head *item, struct cache_detail *cd)
92{
93 struct rsi *rsii = container_of(item, struct rsi, h);
94 if (cache_put(item, cd)) {
95 rsi_free(rsii);
96 kfree(rsii);
97 }
98}
99
100static inline int rsi_hash(struct rsi *item)
101{
102 return hash_mem(item->in_handle.data, item->in_handle.len, RSI_HASHBITS)
103 ^ hash_mem(item->in_token.data, item->in_token.len, RSI_HASHBITS);
104}
105
106static inline int rsi_match(struct rsi *item, struct rsi *tmp)
107{
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 ? kmalloc(len, GFP_KERNEL) : NULL);
116 if (dst->data)
117 memcpy(dst->data, src, len);
118 if (len && !dst->data)
119 return -ENOMEM;
120 return 0;
121}
122
123static inline int dup_netobj(struct xdr_netobj *dst, struct xdr_netobj *src)
124{
125 return dup_to_netobj(dst, src->data, src->len);
126}
127
128static inline void rsi_init(struct rsi *new, struct rsi *item)
129{
130 new->out_handle.data = NULL;
131 new->out_handle.len = 0;
132 new->out_token.data = NULL;
133 new->out_token.len = 0;
134 new->in_handle.len = item->in_handle.len;
135 item->in_handle.len = 0;
136 new->in_token.len = item->in_token.len;
137 item->in_token.len = 0;
138 new->in_handle.data = item->in_handle.data;
139 item->in_handle.data = NULL;
140 new->in_token.data = item->in_token.data;
141 item->in_token.data = NULL;
142}
143
144static inline void rsi_update(struct rsi *new, struct rsi *item)
145{
146 BUG_ON(new->out_handle.data || new->out_token.data);
147 new->out_handle.len = item->out_handle.len;
148 item->out_handle.len = 0;
149 new->out_token.len = item->out_token.len;
150 item->out_token.len = 0;
151 new->out_handle.data = item->out_handle.data;
152 item->out_handle.data = NULL;
153 new->out_token.data = item->out_token.data;
154 item->out_token.data = NULL;
155
156 new->major_status = item->major_status;
157 new->minor_status = item->minor_status;
158}
159
160static void rsi_request(struct cache_detail *cd,
161 struct cache_head *h,
162 char **bpp, int *blen)
163{
164 struct rsi *rsii = container_of(h, struct rsi, h);
165
166 qword_addhex(bpp, blen, rsii->in_handle.data, rsii->in_handle.len);
167 qword_addhex(bpp, blen, rsii->in_token.data, rsii->in_token.len);
168 (*bpp)[-1] = '\n';
169}
170
171
172static int rsi_parse(struct cache_detail *cd,
173 char *mesg, int mlen)
174{
175 /* context token expiry major minor context token */
176 char *buf = mesg;
177 char *ep;
178 int len;
179 struct rsi rsii, *rsip = NULL;
180 time_t expiry;
181 int status = -EINVAL;
182
183 memset(&rsii, 0, sizeof(rsii));
184 /* handle */
185 len = qword_get(&mesg, buf, mlen);
186 if (len < 0)
187 goto out;
188 status = -ENOMEM;
189 if (dup_to_netobj(&rsii.in_handle, buf, len))
190 goto out;
191
192 /* token */
193 len = qword_get(&mesg, buf, mlen);
194 status = -EINVAL;
195 if (len < 0)
196 goto out;
197 status = -ENOMEM;
198 if (dup_to_netobj(&rsii.in_token, buf, len))
199 goto out;
200
201 rsii.h.flags = 0;
202 /* expiry */
203 expiry = get_expiry(&mesg);
204 status = -EINVAL;
205 if (expiry == 0)
206 goto out;
207
208 /* major/minor */
209 len = qword_get(&mesg, buf, mlen);
210 if (len < 0)
211 goto out;
212 if (len == 0) {
213 goto out;
214 } else {
215 rsii.major_status = simple_strtoul(buf, &ep, 10);
216 if (*ep)
217 goto out;
218 len = qword_get(&mesg, buf, mlen);
219 if (len <= 0)
220 goto out;
221 rsii.minor_status = simple_strtoul(buf, &ep, 10);
222 if (*ep)
223 goto out;
224
225 /* out_handle */
226 len = qword_get(&mesg, buf, mlen);
227 if (len < 0)
228 goto out;
229 status = -ENOMEM;
230 if (dup_to_netobj(&rsii.out_handle, buf, len))
231 goto out;
232
233 /* out_token */
234 len = qword_get(&mesg, buf, mlen);
235 status = -EINVAL;
236 if (len < 0)
237 goto out;
238 status = -ENOMEM;
239 if (dup_to_netobj(&rsii.out_token, buf, len))
240 goto out;
241 }
242 rsii.h.expiry_time = expiry;
243 rsip = rsi_lookup(&rsii, 1);
244 status = 0;
245out:
246 rsi_free(&rsii);
247 if (rsip)
248 rsi_put(&rsip->h, &rsi_cache);
249 return status;
250}
251
252static struct cache_detail rsi_cache = {
Bruce Allanf35279d2005-09-06 15:17:08 -0700253 .owner = THIS_MODULE,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254 .hash_size = RSI_HASHMAX,
255 .hash_table = rsi_table,
256 .name = "auth.rpcsec.init",
257 .cache_put = rsi_put,
258 .cache_request = rsi_request,
259 .cache_parse = rsi_parse,
260};
261
262static DefineSimpleCacheLookup(rsi, 0)
263
264/*
265 * The rpcsec_context cache is used to store a context that is
266 * used in data exchange.
267 * The key is a context handle. The content is:
268 * uid, gidlist, mechanism, service-set, mech-specific-data
269 */
270
271#define RSC_HASHBITS 10
272#define RSC_HASHMAX (1<<RSC_HASHBITS)
273#define RSC_HASHMASK (RSC_HASHMAX-1)
274
275#define GSS_SEQ_WIN 128
276
277struct gss_svc_seq_data {
278 /* highest seq number seen so far: */
279 int sd_max;
280 /* for i such that sd_max-GSS_SEQ_WIN < i <= sd_max, the i-th bit of
281 * sd_win is nonzero iff sequence number i has been seen already: */
282 unsigned long sd_win[GSS_SEQ_WIN/BITS_PER_LONG];
283 spinlock_t sd_lock;
284};
285
286struct rsc {
287 struct cache_head h;
288 struct xdr_netobj handle;
289 struct svc_cred cred;
290 struct gss_svc_seq_data seqdata;
291 struct gss_ctx *mechctx;
292};
293
294static struct cache_head *rsc_table[RSC_HASHMAX];
295static struct cache_detail rsc_cache;
296static struct rsc *rsc_lookup(struct rsc *item, int set);
297
298static void rsc_free(struct rsc *rsci)
299{
300 kfree(rsci->handle.data);
301 if (rsci->mechctx)
302 gss_delete_sec_context(&rsci->mechctx);
303 if (rsci->cred.cr_group_info)
304 put_group_info(rsci->cred.cr_group_info);
305}
306
307static void rsc_put(struct cache_head *item, struct cache_detail *cd)
308{
309 struct rsc *rsci = container_of(item, struct rsc, h);
310
311 if (cache_put(item, cd)) {
312 rsc_free(rsci);
313 kfree(rsci);
314 }
315}
316
317static inline int
318rsc_hash(struct rsc *rsci)
319{
320 return hash_mem(rsci->handle.data, rsci->handle.len, RSC_HASHBITS);
321}
322
323static inline int
324rsc_match(struct rsc *new, struct rsc *tmp)
325{
326 return netobj_equal(&new->handle, &tmp->handle);
327}
328
329static inline void
330rsc_init(struct rsc *new, struct rsc *tmp)
331{
332 new->handle.len = tmp->handle.len;
333 tmp->handle.len = 0;
334 new->handle.data = tmp->handle.data;
335 tmp->handle.data = NULL;
336 new->mechctx = NULL;
337 new->cred.cr_group_info = NULL;
338}
339
340static inline void
341rsc_update(struct rsc *new, struct rsc *tmp)
342{
343 new->mechctx = tmp->mechctx;
344 tmp->mechctx = NULL;
345 memset(&new->seqdata, 0, sizeof(new->seqdata));
346 spin_lock_init(&new->seqdata.sd_lock);
347 new->cred = tmp->cred;
348 tmp->cred.cr_group_info = NULL;
349}
350
351static int rsc_parse(struct cache_detail *cd,
352 char *mesg, int mlen)
353{
354 /* contexthandle expiry [ uid gid N <n gids> mechname ...mechdata... ] */
355 char *buf = mesg;
356 int len, rv;
357 struct rsc rsci, *rscp = NULL;
358 time_t expiry;
359 int status = -EINVAL;
360
361 memset(&rsci, 0, sizeof(rsci));
362 /* context handle */
363 len = qword_get(&mesg, buf, mlen);
364 if (len < 0) goto out;
365 status = -ENOMEM;
366 if (dup_to_netobj(&rsci.handle, buf, len))
367 goto out;
368
369 rsci.h.flags = 0;
370 /* expiry */
371 expiry = get_expiry(&mesg);
372 status = -EINVAL;
373 if (expiry == 0)
374 goto out;
375
376 /* uid, or NEGATIVE */
377 rv = get_int(&mesg, &rsci.cred.cr_uid);
378 if (rv == -EINVAL)
379 goto out;
380 if (rv == -ENOENT)
381 set_bit(CACHE_NEGATIVE, &rsci.h.flags);
382 else {
383 int N, i;
384 struct gss_api_mech *gm;
385
386 /* gid */
387 if (get_int(&mesg, &rsci.cred.cr_gid))
388 goto out;
389
390 /* number of additional gid's */
391 if (get_int(&mesg, &N))
392 goto out;
393 status = -ENOMEM;
394 rsci.cred.cr_group_info = groups_alloc(N);
395 if (rsci.cred.cr_group_info == NULL)
396 goto out;
397
398 /* gid's */
399 status = -EINVAL;
400 for (i=0; i<N; i++) {
401 gid_t gid;
402 if (get_int(&mesg, &gid))
403 goto out;
404 GROUP_AT(rsci.cred.cr_group_info, i) = gid;
405 }
406
407 /* mech name */
408 len = qword_get(&mesg, buf, mlen);
409 if (len < 0)
410 goto out;
411 gm = gss_mech_get_by_name(buf);
412 status = -EOPNOTSUPP;
413 if (!gm)
414 goto out;
415
416 status = -EINVAL;
417 /* mech-specific data: */
418 len = qword_get(&mesg, buf, mlen);
419 if (len < 0) {
420 gss_mech_put(gm);
421 goto out;
422 }
J. Bruce Fields5fb8b492006-01-18 17:43:26 -0800423 status = gss_import_sec_context(buf, len, gm, &rsci.mechctx);
424 if (status) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700425 gss_mech_put(gm);
426 goto out;
427 }
428 gss_mech_put(gm);
429 }
430 rsci.h.expiry_time = expiry;
431 rscp = rsc_lookup(&rsci, 1);
432 status = 0;
433out:
434 rsc_free(&rsci);
435 if (rscp)
436 rsc_put(&rscp->h, &rsc_cache);
437 return status;
438}
439
440static struct cache_detail rsc_cache = {
Bruce Allanf35279d2005-09-06 15:17:08 -0700441 .owner = THIS_MODULE,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442 .hash_size = RSC_HASHMAX,
443 .hash_table = rsc_table,
444 .name = "auth.rpcsec.context",
445 .cache_put = rsc_put,
446 .cache_parse = rsc_parse,
447};
448
449static DefineSimpleCacheLookup(rsc, 0);
450
451static struct rsc *
452gss_svc_searchbyctx(struct xdr_netobj *handle)
453{
454 struct rsc rsci;
455 struct rsc *found;
456
457 memset(&rsci, 0, sizeof(rsci));
458 if (dup_to_netobj(&rsci.handle, handle->data, handle->len))
459 return NULL;
460 found = rsc_lookup(&rsci, 0);
461 rsc_free(&rsci);
462 if (!found)
463 return NULL;
464 if (cache_check(&rsc_cache, &found->h, NULL))
465 return NULL;
466 return found;
467}
468
469/* Implements sequence number algorithm as specified in RFC 2203. */
470static int
471gss_check_seq_num(struct rsc *rsci, int seq_num)
472{
473 struct gss_svc_seq_data *sd = &rsci->seqdata;
474
475 spin_lock(&sd->sd_lock);
476 if (seq_num > sd->sd_max) {
477 if (seq_num >= sd->sd_max + GSS_SEQ_WIN) {
478 memset(sd->sd_win,0,sizeof(sd->sd_win));
479 sd->sd_max = seq_num;
480 } else while (sd->sd_max < seq_num) {
481 sd->sd_max++;
482 __clear_bit(sd->sd_max % GSS_SEQ_WIN, sd->sd_win);
483 }
484 __set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win);
485 goto ok;
486 } else if (seq_num <= sd->sd_max - GSS_SEQ_WIN) {
487 goto drop;
488 }
489 /* sd_max - GSS_SEQ_WIN < seq_num <= sd_max */
490 if (__test_and_set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win))
491 goto drop;
492ok:
493 spin_unlock(&sd->sd_lock);
494 return 1;
495drop:
496 spin_unlock(&sd->sd_lock);
497 return 0;
498}
499
500static inline u32 round_up_to_quad(u32 i)
501{
502 return (i + 3 ) & ~3;
503}
504
505static inline int
506svc_safe_getnetobj(struct kvec *argv, struct xdr_netobj *o)
507{
508 int l;
509
510 if (argv->iov_len < 4)
511 return -1;
512 o->len = ntohl(svc_getu32(argv));
513 l = round_up_to_quad(o->len);
514 if (argv->iov_len < l)
515 return -1;
516 o->data = argv->iov_base;
517 argv->iov_base += l;
518 argv->iov_len -= l;
519 return 0;
520}
521
522static inline int
523svc_safe_putnetobj(struct kvec *resv, struct xdr_netobj *o)
524{
525 u32 *p;
526
527 if (resv->iov_len + 4 > PAGE_SIZE)
528 return -1;
529 svc_putu32(resv, htonl(o->len));
530 p = resv->iov_base + resv->iov_len;
531 resv->iov_len += round_up_to_quad(o->len);
532 if (resv->iov_len > PAGE_SIZE)
533 return -1;
534 memcpy(p, o->data, o->len);
535 memset((u8 *)p + o->len, 0, round_up_to_quad(o->len) - o->len);
536 return 0;
537}
538
539/* Verify the checksum on the header and return SVC_OK on success.
540 * Otherwise, return SVC_DROP (in the case of a bad sequence number)
541 * or return SVC_DENIED and indicate error in authp.
542 */
543static int
544gss_verify_header(struct svc_rqst *rqstp, struct rsc *rsci,
545 u32 *rpcstart, struct rpc_gss_wire_cred *gc, u32 *authp)
546{
547 struct gss_ctx *ctx_id = rsci->mechctx;
548 struct xdr_buf rpchdr;
549 struct xdr_netobj checksum;
550 u32 flavor = 0;
551 struct kvec *argv = &rqstp->rq_arg.head[0];
552 struct kvec iov;
553
554 /* data to compute the checksum over: */
555 iov.iov_base = rpcstart;
556 iov.iov_len = (u8 *)argv->iov_base - (u8 *)rpcstart;
557 xdr_buf_from_iov(&iov, &rpchdr);
558
559 *authp = rpc_autherr_badverf;
560 if (argv->iov_len < 4)
561 return SVC_DENIED;
562 flavor = ntohl(svc_getu32(argv));
563 if (flavor != RPC_AUTH_GSS)
564 return SVC_DENIED;
565 if (svc_safe_getnetobj(argv, &checksum))
566 return SVC_DENIED;
567
568 if (rqstp->rq_deferred) /* skip verification of revisited request */
569 return SVC_OK;
J. Bruce Fields00fd6e12005-10-13 16:55:18 -0400570 if (gss_verify_mic(ctx_id, &rpchdr, &checksum) != GSS_S_COMPLETE) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700571 *authp = rpcsec_gsserr_credproblem;
572 return SVC_DENIED;
573 }
574
575 if (gc->gc_seq > MAXSEQ) {
576 dprintk("RPC: svcauth_gss: discarding request with large sequence number %d\n",
577 gc->gc_seq);
578 *authp = rpcsec_gsserr_ctxproblem;
579 return SVC_DENIED;
580 }
581 if (!gss_check_seq_num(rsci, gc->gc_seq)) {
582 dprintk("RPC: svcauth_gss: discarding request with old sequence number %d\n",
583 gc->gc_seq);
584 return SVC_DROP;
585 }
586 return SVC_OK;
587}
588
589static int
Andy Adamson822f1002006-01-18 17:43:24 -0800590gss_write_null_verf(struct svc_rqst *rqstp)
591{
592 u32 *p;
593
594 svc_putu32(rqstp->rq_res.head, htonl(RPC_AUTH_NULL));
595 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len;
596 /* don't really need to check if head->iov_len > PAGE_SIZE ... */
597 *p++ = 0;
598 if (!xdr_ressize_check(rqstp, p))
599 return -1;
600 return 0;
601}
602
603static int
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604gss_write_verf(struct svc_rqst *rqstp, struct gss_ctx *ctx_id, u32 seq)
605{
606 u32 xdr_seq;
607 u32 maj_stat;
608 struct xdr_buf verf_data;
609 struct xdr_netobj mic;
610 u32 *p;
611 struct kvec iov;
612
613 svc_putu32(rqstp->rq_res.head, htonl(RPC_AUTH_GSS));
614 xdr_seq = htonl(seq);
615
616 iov.iov_base = &xdr_seq;
617 iov.iov_len = sizeof(xdr_seq);
618 xdr_buf_from_iov(&iov, &verf_data);
619 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len;
620 mic.data = (u8 *)(p + 1);
J. Bruce Fields00fd6e12005-10-13 16:55:18 -0400621 maj_stat = gss_get_mic(ctx_id, &verf_data, &mic);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700622 if (maj_stat != GSS_S_COMPLETE)
623 return -1;
624 *p++ = htonl(mic.len);
625 memset((u8 *)p + mic.len, 0, round_up_to_quad(mic.len) - mic.len);
626 p += XDR_QUADLEN(mic.len);
627 if (!xdr_ressize_check(rqstp, p))
628 return -1;
629 return 0;
630}
631
632struct gss_domain {
633 struct auth_domain h;
634 u32 pseudoflavor;
635};
636
637static struct auth_domain *
638find_gss_auth_domain(struct gss_ctx *ctx, u32 svc)
639{
640 char *name;
641
642 name = gss_service_to_auth_domain_name(ctx->mech_type, svc);
643 if (!name)
644 return NULL;
645 return auth_domain_find(name);
646}
647
648int
649svcauth_gss_register_pseudoflavor(u32 pseudoflavor, char * name)
650{
651 struct gss_domain *new;
652 struct auth_domain *test;
653 int stat = -ENOMEM;
654
655 new = kmalloc(sizeof(*new), GFP_KERNEL);
656 if (!new)
657 goto out;
658 cache_init(&new->h.h);
659 new->h.name = kmalloc(strlen(name) + 1, GFP_KERNEL);
660 if (!new->h.name)
661 goto out_free_dom;
662 strcpy(new->h.name, name);
663 new->h.flavour = RPC_AUTH_GSS;
664 new->pseudoflavor = pseudoflavor;
665 new->h.h.expiry_time = NEVER;
666
667 test = auth_domain_lookup(&new->h, 1);
668 if (test == &new->h) {
669 BUG_ON(atomic_dec_and_test(&new->h.h.refcnt));
670 } else { /* XXX Duplicate registration? */
671 auth_domain_put(&new->h);
672 goto out;
673 }
674 return 0;
675
676out_free_dom:
677 kfree(new);
678out:
679 return stat;
680}
681
682EXPORT_SYMBOL(svcauth_gss_register_pseudoflavor);
683
684static inline int
685read_u32_from_xdr_buf(struct xdr_buf *buf, int base, u32 *obj)
686{
687 u32 raw;
688 int status;
689
690 status = read_bytes_from_xdr_buf(buf, base, &raw, sizeof(*obj));
691 if (status)
692 return status;
693 *obj = ntohl(raw);
694 return 0;
695}
696
697/* It would be nice if this bit of code could be shared with the client.
698 * Obstacles:
699 * The client shouldn't malloc(), would have to pass in own memory.
700 * The server uses base of head iovec as read pointer, while the
701 * client uses separate pointer. */
702static int
703unwrap_integ_data(struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx)
704{
705 int stat = -EINVAL;
706 u32 integ_len, maj_stat;
707 struct xdr_netobj mic;
708 struct xdr_buf integ_buf;
709
710 integ_len = ntohl(svc_getu32(&buf->head[0]));
711 if (integ_len & 3)
712 goto out;
713 if (integ_len > buf->len)
714 goto out;
715 if (xdr_buf_subsegment(buf, &integ_buf, 0, integ_len))
716 BUG();
717 /* copy out mic... */
718 if (read_u32_from_xdr_buf(buf, integ_len, &mic.len))
719 BUG();
720 if (mic.len > RPC_MAX_AUTH_SIZE)
721 goto out;
722 mic.data = kmalloc(mic.len, GFP_KERNEL);
723 if (!mic.data)
724 goto out;
725 if (read_bytes_from_xdr_buf(buf, integ_len + 4, mic.data, mic.len))
726 goto out;
J. Bruce Fields00fd6e12005-10-13 16:55:18 -0400727 maj_stat = gss_verify_mic(ctx, &integ_buf, &mic);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700728 if (maj_stat != GSS_S_COMPLETE)
729 goto out;
730 if (ntohl(svc_getu32(&buf->head[0])) != seq)
731 goto out;
732 stat = 0;
733out:
734 return stat;
735}
736
737struct gss_svc_data {
738 /* decoded gss client cred: */
739 struct rpc_gss_wire_cred clcred;
740 /* pointer to the beginning of the procedure-specific results,
741 * which may be encrypted/checksummed in svcauth_gss_release: */
742 u32 *body_start;
743 struct rsc *rsci;
744};
745
746static int
747svcauth_gss_set_client(struct svc_rqst *rqstp)
748{
749 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
750 struct rsc *rsci = svcdata->rsci;
751 struct rpc_gss_wire_cred *gc = &svcdata->clcred;
752
753 rqstp->rq_client = find_gss_auth_domain(rsci->mechctx, gc->gc_svc);
754 if (rqstp->rq_client == NULL)
755 return SVC_DENIED;
756 return SVC_OK;
757}
758
Kevin Coffman91a47622006-01-18 17:43:25 -0800759static inline int
760gss_write_init_verf(struct svc_rqst *rqstp, struct rsi *rsip)
761{
762 struct rsc *rsci;
763
764 if (rsip->major_status != GSS_S_COMPLETE)
765 return gss_write_null_verf(rqstp);
766 rsci = gss_svc_searchbyctx(&rsip->out_handle);
767 if (rsci == NULL) {
768 rsip->major_status = GSS_S_NO_CONTEXT;
769 return gss_write_null_verf(rqstp);
770 }
771 return gss_write_verf(rqstp, rsci->mechctx, GSS_SEQ_WIN);
772}
773
Linus Torvalds1da177e2005-04-16 15:20:36 -0700774/*
775 * Accept an rpcsec packet.
776 * If context establishment, punt to user space
777 * If data exchange, verify/decrypt
778 * If context destruction, handle here
779 * In the context establishment and destruction case we encode
780 * response here and return SVC_COMPLETE.
781 */
782static int
783svcauth_gss_accept(struct svc_rqst *rqstp, u32 *authp)
784{
785 struct kvec *argv = &rqstp->rq_arg.head[0];
786 struct kvec *resv = &rqstp->rq_res.head[0];
787 u32 crlen;
788 struct xdr_netobj tmpobj;
789 struct gss_svc_data *svcdata = rqstp->rq_auth_data;
790 struct rpc_gss_wire_cred *gc;
791 struct rsc *rsci = NULL;
792 struct rsi *rsip, rsikey;
793 u32 *rpcstart;
794 u32 *reject_stat = resv->iov_base + resv->iov_len;
795 int ret;
796
797 dprintk("RPC: svcauth_gss: argv->iov_len = %zd\n",argv->iov_len);
798
799 *authp = rpc_autherr_badcred;
800 if (!svcdata)
801 svcdata = kmalloc(sizeof(*svcdata), GFP_KERNEL);
802 if (!svcdata)
803 goto auth_err;
804 rqstp->rq_auth_data = svcdata;
805 svcdata->body_start = NULL;
806 svcdata->rsci = NULL;
807 gc = &svcdata->clcred;
808
809 /* start of rpc packet is 7 u32's back from here:
810 * xid direction rpcversion prog vers proc flavour
811 */
812 rpcstart = argv->iov_base;
813 rpcstart -= 7;
814
815 /* credential is:
816 * version(==1), proc(0,1,2,3), seq, service (1,2,3), handle
817 * at least 5 u32s, and is preceeded by length, so that makes 6.
818 */
819
820 if (argv->iov_len < 5 * 4)
821 goto auth_err;
822 crlen = ntohl(svc_getu32(argv));
823 if (ntohl(svc_getu32(argv)) != RPC_GSS_VERSION)
824 goto auth_err;
825 gc->gc_proc = ntohl(svc_getu32(argv));
826 gc->gc_seq = ntohl(svc_getu32(argv));
827 gc->gc_svc = ntohl(svc_getu32(argv));
828 if (svc_safe_getnetobj(argv, &gc->gc_ctx))
829 goto auth_err;
830 if (crlen != round_up_to_quad(gc->gc_ctx.len) + 5 * 4)
831 goto auth_err;
832
833 if ((gc->gc_proc != RPC_GSS_PROC_DATA) && (rqstp->rq_proc != 0))
834 goto auth_err;
835
836 /*
837 * We've successfully parsed the credential. Let's check out the
838 * verifier. An AUTH_NULL verifier is allowed (and required) for
839 * INIT and CONTINUE_INIT requests. AUTH_RPCSEC_GSS is required for
840 * PROC_DATA and PROC_DESTROY.
841 *
842 * AUTH_NULL verifier is 0 (AUTH_NULL), 0 (length).
843 * AUTH_RPCSEC_GSS verifier is:
844 * 6 (AUTH_RPCSEC_GSS), length, checksum.
845 * checksum is calculated over rpcheader from xid up to here.
846 */
847 *authp = rpc_autherr_badverf;
848 switch (gc->gc_proc) {
849 case RPC_GSS_PROC_INIT:
850 case RPC_GSS_PROC_CONTINUE_INIT:
851 if (argv->iov_len < 2 * 4)
852 goto auth_err;
853 if (ntohl(svc_getu32(argv)) != RPC_AUTH_NULL)
854 goto auth_err;
855 if (ntohl(svc_getu32(argv)) != 0)
856 goto auth_err;
857 break;
858 case RPC_GSS_PROC_DATA:
859 case RPC_GSS_PROC_DESTROY:
860 *authp = rpcsec_gsserr_credproblem;
861 rsci = gss_svc_searchbyctx(&gc->gc_ctx);
862 if (!rsci)
863 goto auth_err;
864 switch (gss_verify_header(rqstp, rsci, rpcstart, gc, authp)) {
865 case SVC_OK:
866 break;
867 case SVC_DENIED:
868 goto auth_err;
869 case SVC_DROP:
870 goto drop;
871 }
872 break;
873 default:
874 *authp = rpc_autherr_rejectedcred;
875 goto auth_err;
876 }
877
878 /* now act upon the command: */
879 switch (gc->gc_proc) {
880 case RPC_GSS_PROC_INIT:
881 case RPC_GSS_PROC_CONTINUE_INIT:
882 *authp = rpc_autherr_badcred;
883 if (gc->gc_proc == RPC_GSS_PROC_INIT && gc->gc_ctx.len != 0)
884 goto auth_err;
885 memset(&rsikey, 0, sizeof(rsikey));
886 if (dup_netobj(&rsikey.in_handle, &gc->gc_ctx))
887 goto drop;
888 *authp = rpc_autherr_badverf;
889 if (svc_safe_getnetobj(argv, &tmpobj)) {
890 kfree(rsikey.in_handle.data);
891 goto auth_err;
892 }
893 if (dup_netobj(&rsikey.in_token, &tmpobj)) {
894 kfree(rsikey.in_handle.data);
895 goto drop;
896 }
897
898 rsip = rsi_lookup(&rsikey, 0);
899 rsi_free(&rsikey);
900 if (!rsip) {
901 goto drop;
902 }
903 switch(cache_check(&rsi_cache, &rsip->h, &rqstp->rq_chandle)) {
904 case -EAGAIN:
905 goto drop;
906 case -ENOENT:
907 goto drop;
908 case 0:
Kevin Coffman91a47622006-01-18 17:43:25 -0800909 if (gss_write_init_verf(rqstp, rsip))
910 goto drop;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700911 if (resv->iov_len + 4 > PAGE_SIZE)
912 goto drop;
913 svc_putu32(resv, rpc_success);
914 if (svc_safe_putnetobj(resv, &rsip->out_handle))
915 goto drop;
916 if (resv->iov_len + 3 * 4 > PAGE_SIZE)
917 goto drop;
918 svc_putu32(resv, htonl(rsip->major_status));
919 svc_putu32(resv, htonl(rsip->minor_status));
920 svc_putu32(resv, htonl(GSS_SEQ_WIN));
921 if (svc_safe_putnetobj(resv, &rsip->out_token))
922 goto drop;
923 rqstp->rq_client = NULL;
924 }
925 goto complete;
926 case RPC_GSS_PROC_DESTROY:
927 set_bit(CACHE_NEGATIVE, &rsci->h.flags);
928 if (resv->iov_len + 4 > PAGE_SIZE)
929 goto drop;
930 svc_putu32(resv, rpc_success);
931 goto complete;
932 case RPC_GSS_PROC_DATA:
933 *authp = rpcsec_gsserr_ctxproblem;
934 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
935 goto auth_err;
936 rqstp->rq_cred = rsci->cred;
937 get_group_info(rsci->cred.cr_group_info);
938 *authp = rpc_autherr_badcred;
939 switch (gc->gc_svc) {
940 case RPC_GSS_SVC_NONE:
941 break;
942 case RPC_GSS_SVC_INTEGRITY:
943 if (unwrap_integ_data(&rqstp->rq_arg,
944 gc->gc_seq, rsci->mechctx))
945 goto auth_err;
946 /* placeholders for length and seq. number: */
947 svcdata->body_start = resv->iov_base + resv->iov_len;
948 svc_putu32(resv, 0);
949 svc_putu32(resv, 0);
950 break;
951 case RPC_GSS_SVC_PRIVACY:
952 /* currently unsupported */
953 default:
954 goto auth_err;
955 }
956 svcdata->rsci = rsci;
957 cache_get(&rsci->h);
958 ret = SVC_OK;
959 goto out;
960 }
961auth_err:
962 /* Restore write pointer to original value: */
963 xdr_ressize_check(rqstp, reject_stat);
964 ret = SVC_DENIED;
965 goto out;
966complete:
967 ret = SVC_COMPLETE;
968 goto out;
969drop:
970 ret = SVC_DROP;
971out:
972 if (rsci)
973 rsc_put(&rsci->h, &rsc_cache);
974 return ret;
975}
976
977static int
978svcauth_gss_release(struct svc_rqst *rqstp)
979{
980 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
981 struct rpc_gss_wire_cred *gc = &gsd->clcred;
982 struct xdr_buf *resbuf = &rqstp->rq_res;
983 struct xdr_buf integ_buf;
984 struct xdr_netobj mic;
985 struct kvec *resv;
986 u32 *p;
987 int integ_offset, integ_len;
988 int stat = -EINVAL;
989
990 if (gc->gc_proc != RPC_GSS_PROC_DATA)
991 goto out;
992 /* Release can be called twice, but we only wrap once. */
993 if (gsd->body_start == NULL)
994 goto out;
995 /* normally not set till svc_send, but we need it here: */
996 resbuf->len = resbuf->head[0].iov_len
997 + resbuf->page_len + resbuf->tail[0].iov_len;
998 switch (gc->gc_svc) {
999 case RPC_GSS_SVC_NONE:
1000 break;
1001 case RPC_GSS_SVC_INTEGRITY:
1002 p = gsd->body_start;
1003 gsd->body_start = NULL;
1004 /* move accept_stat to right place: */
1005 memcpy(p, p + 2, 4);
1006 /* don't wrap in failure case: */
1007 /* Note: counting on not getting here if call was not even
1008 * accepted! */
1009 if (*p != rpc_success) {
1010 resbuf->head[0].iov_len -= 2 * 4;
1011 goto out;
1012 }
1013 p++;
1014 integ_offset = (u8 *)(p + 1) - (u8 *)resbuf->head[0].iov_base;
1015 integ_len = resbuf->len - integ_offset;
1016 BUG_ON(integ_len % 4);
1017 *p++ = htonl(integ_len);
1018 *p++ = htonl(gc->gc_seq);
1019 if (xdr_buf_subsegment(resbuf, &integ_buf, integ_offset,
1020 integ_len))
1021 BUG();
1022 if (resbuf->page_len == 0
1023 && resbuf->tail[0].iov_len + RPC_MAX_AUTH_SIZE
1024 < PAGE_SIZE) {
1025 BUG_ON(resbuf->tail[0].iov_len);
1026 /* Use head for everything */
1027 resv = &resbuf->head[0];
1028 } else if (resbuf->tail[0].iov_base == NULL) {
1029 /* copied from nfsd4_encode_read */
1030 svc_take_page(rqstp);
1031 resbuf->tail[0].iov_base = page_address(rqstp
1032 ->rq_respages[rqstp->rq_resused-1]);
1033 rqstp->rq_restailpage = rqstp->rq_resused-1;
1034 resbuf->tail[0].iov_len = 0;
1035 resv = &resbuf->tail[0];
1036 } else {
1037 resv = &resbuf->tail[0];
1038 }
1039 mic.data = (u8 *)resv->iov_base + resv->iov_len + 4;
J. Bruce Fields00fd6e12005-10-13 16:55:18 -04001040 if (gss_get_mic(gsd->rsci->mechctx, &integ_buf, &mic))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001041 goto out_err;
1042 svc_putu32(resv, htonl(mic.len));
1043 memset(mic.data + mic.len, 0,
1044 round_up_to_quad(mic.len) - mic.len);
1045 resv->iov_len += XDR_QUADLEN(mic.len) << 2;
1046 /* not strictly required: */
1047 resbuf->len += XDR_QUADLEN(mic.len) << 2;
1048 BUG_ON(resv->iov_len > PAGE_SIZE);
1049 break;
1050 case RPC_GSS_SVC_PRIVACY:
1051 default:
1052 goto out_err;
1053 }
1054
1055out:
1056 stat = 0;
1057out_err:
1058 if (rqstp->rq_client)
1059 auth_domain_put(rqstp->rq_client);
1060 rqstp->rq_client = NULL;
1061 if (rqstp->rq_cred.cr_group_info)
1062 put_group_info(rqstp->rq_cred.cr_group_info);
1063 rqstp->rq_cred.cr_group_info = NULL;
1064 if (gsd->rsci)
1065 rsc_put(&gsd->rsci->h, &rsc_cache);
1066 gsd->rsci = NULL;
1067
1068 return stat;
1069}
1070
1071static void
1072svcauth_gss_domain_release(struct auth_domain *dom)
1073{
1074 struct gss_domain *gd = container_of(dom, struct gss_domain, h);
1075
1076 kfree(dom->name);
1077 kfree(gd);
1078}
1079
1080static struct auth_ops svcauthops_gss = {
1081 .name = "rpcsec_gss",
1082 .owner = THIS_MODULE,
1083 .flavour = RPC_AUTH_GSS,
1084 .accept = svcauth_gss_accept,
1085 .release = svcauth_gss_release,
1086 .domain_release = svcauth_gss_domain_release,
1087 .set_client = svcauth_gss_set_client,
1088};
1089
1090int
1091gss_svc_init(void)
1092{
1093 int rv = svc_auth_register(RPC_AUTH_GSS, &svcauthops_gss);
1094 if (rv == 0) {
1095 cache_register(&rsc_cache);
1096 cache_register(&rsi_cache);
1097 }
1098 return rv;
1099}
1100
1101void
1102gss_svc_shutdown(void)
1103{
Bruce Allanf35279d2005-09-06 15:17:08 -07001104 if (cache_unregister(&rsc_cache))
1105 printk(KERN_ERR "auth_rpcgss: failed to unregister rsc cache\n");
1106 if (cache_unregister(&rsi_cache))
1107 printk(KERN_ERR "auth_rpcgss: failed to unregister rsi cache\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001108 svc_auth_unregister(RPC_AUTH_GSS);
1109}