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1/*
2 * linux/net/sunrpc/auth_gss/auth_gss.c
3 *
4 * RPCSEC_GSS client authentication.
5 *
6 * Copyright (c) 2000 The Regents of the University of Michigan.
7 * All rights reserved.
8 *
9 * Dug Song <dugsong@monkey.org>
10 * Andy Adamson <andros@umich.edu>
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 *
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. Neither the name of the University nor the names of its
22 * contributors may be used to endorse or promote products derived
23 * from this software without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
26 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
27 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
28 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
32 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
33 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
34 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
35 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 */
37
38
39#include <linux/module.h>
40#include <linux/init.h>
41#include <linux/types.h>
42#include <linux/slab.h>
43#include <linux/sched.h>
44#include <linux/pagemap.h>
45#include <linux/sunrpc/clnt.h>
46#include <linux/sunrpc/auth.h>
47#include <linux/sunrpc/auth_gss.h>
48#include <linux/sunrpc/svcauth_gss.h>
49#include <linux/sunrpc/gss_err.h>
50#include <linux/workqueue.h>
51#include <linux/sunrpc/rpc_pipe_fs.h>
52#include <linux/sunrpc/gss_api.h>
53#include <asm/uaccess.h>
54
55static const struct rpc_authops authgss_ops;
56
57static const struct rpc_credops gss_credops;
58static const struct rpc_credops gss_nullops;
59
60#define GSS_RETRY_EXPIRED 5
61static unsigned int gss_expired_cred_retry_delay = GSS_RETRY_EXPIRED;
62
63#ifdef RPC_DEBUG
64# define RPCDBG_FACILITY RPCDBG_AUTH
65#endif
66
67#define GSS_CRED_SLACK (RPC_MAX_AUTH_SIZE * 2)
68/* length of a krb5 verifier (48), plus data added before arguments when
69 * using integrity (two 4-byte integers): */
70#define GSS_VERF_SLACK 100
71
72struct gss_auth {
73 struct kref kref;
74 struct rpc_auth rpc_auth;
75 struct gss_api_mech *mech;
76 enum rpc_gss_svc service;
77 struct rpc_clnt *client;
78 /*
79 * There are two upcall pipes; dentry[1], named "gssd", is used
80 * for the new text-based upcall; dentry[0] is named after the
81 * mechanism (for example, "krb5") and exists for
82 * backwards-compatibility with older gssd's.
83 */
84 struct rpc_pipe *pipe[2];
85};
86
87/* pipe_version >= 0 if and only if someone has a pipe open. */
88static int pipe_version = -1;
89static atomic_t pipe_users = ATOMIC_INIT(0);
90static DEFINE_SPINLOCK(pipe_version_lock);
91static struct rpc_wait_queue pipe_version_rpc_waitqueue;
92static DECLARE_WAIT_QUEUE_HEAD(pipe_version_waitqueue);
93
94static void gss_free_ctx(struct gss_cl_ctx *);
95static const struct rpc_pipe_ops gss_upcall_ops_v0;
96static const struct rpc_pipe_ops gss_upcall_ops_v1;
97
98static inline struct gss_cl_ctx *
99gss_get_ctx(struct gss_cl_ctx *ctx)
100{
101 atomic_inc(&ctx->count);
102 return ctx;
103}
104
105static inline void
106gss_put_ctx(struct gss_cl_ctx *ctx)
107{
108 if (atomic_dec_and_test(&ctx->count))
109 gss_free_ctx(ctx);
110}
111
112/* gss_cred_set_ctx:
113 * called by gss_upcall_callback and gss_create_upcall in order
114 * to set the gss context. The actual exchange of an old context
115 * and a new one is protected by the pipe->lock.
116 */
117static void
118gss_cred_set_ctx(struct rpc_cred *cred, struct gss_cl_ctx *ctx)
119{
120 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
121
122 if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags))
123 return;
124 gss_get_ctx(ctx);
125 rcu_assign_pointer(gss_cred->gc_ctx, ctx);
126 set_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
127 smp_mb__before_clear_bit();
128 clear_bit(RPCAUTH_CRED_NEW, &cred->cr_flags);
129}
130
131static const void *
132simple_get_bytes(const void *p, const void *end, void *res, size_t len)
133{
134 const void *q = (const void *)((const char *)p + len);
135 if (unlikely(q > end || q < p))
136 return ERR_PTR(-EFAULT);
137 memcpy(res, p, len);
138 return q;
139}
140
141static inline const void *
142simple_get_netobj(const void *p, const void *end, struct xdr_netobj *dest)
143{
144 const void *q;
145 unsigned int len;
146
147 p = simple_get_bytes(p, end, &len, sizeof(len));
148 if (IS_ERR(p))
149 return p;
150 q = (const void *)((const char *)p + len);
151 if (unlikely(q > end || q < p))
152 return ERR_PTR(-EFAULT);
153 dest->data = kmemdup(p, len, GFP_NOFS);
154 if (unlikely(dest->data == NULL))
155 return ERR_PTR(-ENOMEM);
156 dest->len = len;
157 return q;
158}
159
160static struct gss_cl_ctx *
161gss_cred_get_ctx(struct rpc_cred *cred)
162{
163 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
164 struct gss_cl_ctx *ctx = NULL;
165
166 rcu_read_lock();
167 if (gss_cred->gc_ctx)
168 ctx = gss_get_ctx(gss_cred->gc_ctx);
169 rcu_read_unlock();
170 return ctx;
171}
172
173static struct gss_cl_ctx *
174gss_alloc_context(void)
175{
176 struct gss_cl_ctx *ctx;
177
178 ctx = kzalloc(sizeof(*ctx), GFP_NOFS);
179 if (ctx != NULL) {
180 ctx->gc_proc = RPC_GSS_PROC_DATA;
181 ctx->gc_seq = 1; /* NetApp 6.4R1 doesn't accept seq. no. 0 */
182 spin_lock_init(&ctx->gc_seq_lock);
183 atomic_set(&ctx->count,1);
184 }
185 return ctx;
186}
187
188#define GSSD_MIN_TIMEOUT (60 * 60)
189static const void *
190gss_fill_context(const void *p, const void *end, struct gss_cl_ctx *ctx, struct gss_api_mech *gm)
191{
192 const void *q;
193 unsigned int seclen;
194 unsigned int timeout;
195 u32 window_size;
196 int ret;
197
198 /* First unsigned int gives the lifetime (in seconds) of the cred */
199 p = simple_get_bytes(p, end, &timeout, sizeof(timeout));
200 if (IS_ERR(p))
201 goto err;
202 if (timeout == 0)
203 timeout = GSSD_MIN_TIMEOUT;
204 ctx->gc_expiry = jiffies + (unsigned long)timeout * HZ * 3 / 4;
205 /* Sequence number window. Determines the maximum number of simultaneous requests */
206 p = simple_get_bytes(p, end, &window_size, sizeof(window_size));
207 if (IS_ERR(p))
208 goto err;
209 ctx->gc_win = window_size;
210 /* gssd signals an error by passing ctx->gc_win = 0: */
211 if (ctx->gc_win == 0) {
212 /*
213 * in which case, p points to an error code. Anything other
214 * than -EKEYEXPIRED gets converted to -EACCES.
215 */
216 p = simple_get_bytes(p, end, &ret, sizeof(ret));
217 if (!IS_ERR(p))
218 p = (ret == -EKEYEXPIRED) ? ERR_PTR(-EKEYEXPIRED) :
219 ERR_PTR(-EACCES);
220 goto err;
221 }
222 /* copy the opaque wire context */
223 p = simple_get_netobj(p, end, &ctx->gc_wire_ctx);
224 if (IS_ERR(p))
225 goto err;
226 /* import the opaque security context */
227 p = simple_get_bytes(p, end, &seclen, sizeof(seclen));
228 if (IS_ERR(p))
229 goto err;
230 q = (const void *)((const char *)p + seclen);
231 if (unlikely(q > end || q < p)) {
232 p = ERR_PTR(-EFAULT);
233 goto err;
234 }
235 ret = gss_import_sec_context(p, seclen, gm, &ctx->gc_gss_ctx, GFP_NOFS);
236 if (ret < 0) {
237 p = ERR_PTR(ret);
238 goto err;
239 }
240 return q;
241err:
242 dprintk("RPC: gss_fill_context returning %ld\n", -PTR_ERR(p));
243 return p;
244}
245
246#define UPCALL_BUF_LEN 128
247
248struct gss_upcall_msg {
249 atomic_t count;
250 uid_t uid;
251 struct rpc_pipe_msg msg;
252 struct list_head list;
253 struct gss_auth *auth;
254 struct rpc_pipe *pipe;
255 struct rpc_wait_queue rpc_waitqueue;
256 wait_queue_head_t waitqueue;
257 struct gss_cl_ctx *ctx;
258 char databuf[UPCALL_BUF_LEN];
259};
260
261static int get_pipe_version(void)
262{
263 int ret;
264
265 spin_lock(&pipe_version_lock);
266 if (pipe_version >= 0) {
267 atomic_inc(&pipe_users);
268 ret = pipe_version;
269 } else
270 ret = -EAGAIN;
271 spin_unlock(&pipe_version_lock);
272 return ret;
273}
274
275static void put_pipe_version(void)
276{
277 if (atomic_dec_and_lock(&pipe_users, &pipe_version_lock)) {
278 pipe_version = -1;
279 spin_unlock(&pipe_version_lock);
280 }
281}
282
283static void
284gss_release_msg(struct gss_upcall_msg *gss_msg)
285{
286 if (!atomic_dec_and_test(&gss_msg->count))
287 return;
288 put_pipe_version();
289 BUG_ON(!list_empty(&gss_msg->list));
290 if (gss_msg->ctx != NULL)
291 gss_put_ctx(gss_msg->ctx);
292 rpc_destroy_wait_queue(&gss_msg->rpc_waitqueue);
293 kfree(gss_msg);
294}
295
296static struct gss_upcall_msg *
297__gss_find_upcall(struct rpc_pipe *pipe, uid_t uid)
298{
299 struct gss_upcall_msg *pos;
300 list_for_each_entry(pos, &pipe->in_downcall, list) {
301 if (pos->uid != uid)
302 continue;
303 atomic_inc(&pos->count);
304 dprintk("RPC: gss_find_upcall found msg %p\n", pos);
305 return pos;
306 }
307 dprintk("RPC: gss_find_upcall found nothing\n");
308 return NULL;
309}
310
311/* Try to add an upcall to the pipefs queue.
312 * If an upcall owned by our uid already exists, then we return a reference
313 * to that upcall instead of adding the new upcall.
314 */
315static inline struct gss_upcall_msg *
316gss_add_msg(struct gss_upcall_msg *gss_msg)
317{
318 struct rpc_pipe *pipe = gss_msg->pipe;
319 struct gss_upcall_msg *old;
320
321 spin_lock(&pipe->lock);
322 old = __gss_find_upcall(pipe, gss_msg->uid);
323 if (old == NULL) {
324 atomic_inc(&gss_msg->count);
325 list_add(&gss_msg->list, &pipe->in_downcall);
326 } else
327 gss_msg = old;
328 spin_unlock(&pipe->lock);
329 return gss_msg;
330}
331
332static void
333__gss_unhash_msg(struct gss_upcall_msg *gss_msg)
334{
335 list_del_init(&gss_msg->list);
336 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno);
337 wake_up_all(&gss_msg->waitqueue);
338 atomic_dec(&gss_msg->count);
339}
340
341static void
342gss_unhash_msg(struct gss_upcall_msg *gss_msg)
343{
344 struct rpc_pipe *pipe = gss_msg->pipe;
345
346 if (list_empty(&gss_msg->list))
347 return;
348 spin_lock(&pipe->lock);
349 if (!list_empty(&gss_msg->list))
350 __gss_unhash_msg(gss_msg);
351 spin_unlock(&pipe->lock);
352}
353
354static void
355gss_handle_downcall_result(struct gss_cred *gss_cred, struct gss_upcall_msg *gss_msg)
356{
357 switch (gss_msg->msg.errno) {
358 case 0:
359 if (gss_msg->ctx == NULL)
360 break;
361 clear_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags);
362 gss_cred_set_ctx(&gss_cred->gc_base, gss_msg->ctx);
363 break;
364 case -EKEYEXPIRED:
365 set_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags);
366 }
367 gss_cred->gc_upcall_timestamp = jiffies;
368 gss_cred->gc_upcall = NULL;
369 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno);
370}
371
372static void
373gss_upcall_callback(struct rpc_task *task)
374{
375 struct gss_cred *gss_cred = container_of(task->tk_rqstp->rq_cred,
376 struct gss_cred, gc_base);
377 struct gss_upcall_msg *gss_msg = gss_cred->gc_upcall;
378 struct rpc_pipe *pipe = gss_msg->pipe;
379
380 spin_lock(&pipe->lock);
381 gss_handle_downcall_result(gss_cred, gss_msg);
382 spin_unlock(&pipe->lock);
383 task->tk_status = gss_msg->msg.errno;
384 gss_release_msg(gss_msg);
385}
386
387static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg)
388{
389 gss_msg->msg.data = &gss_msg->uid;
390 gss_msg->msg.len = sizeof(gss_msg->uid);
391}
392
393static void gss_encode_v1_msg(struct gss_upcall_msg *gss_msg,
394 struct rpc_clnt *clnt,
395 const char *service_name)
396{
397 struct gss_api_mech *mech = gss_msg->auth->mech;
398 char *p = gss_msg->databuf;
399 int len = 0;
400
401 gss_msg->msg.len = sprintf(gss_msg->databuf, "mech=%s uid=%d ",
402 mech->gm_name,
403 gss_msg->uid);
404 p += gss_msg->msg.len;
405 if (clnt->cl_principal) {
406 len = sprintf(p, "target=%s ", clnt->cl_principal);
407 p += len;
408 gss_msg->msg.len += len;
409 }
410 if (service_name != NULL) {
411 len = sprintf(p, "service=%s ", service_name);
412 p += len;
413 gss_msg->msg.len += len;
414 }
415 if (mech->gm_upcall_enctypes) {
416 len = sprintf(p, "enctypes=%s ", mech->gm_upcall_enctypes);
417 p += len;
418 gss_msg->msg.len += len;
419 }
420 len = sprintf(p, "\n");
421 gss_msg->msg.len += len;
422
423 gss_msg->msg.data = gss_msg->databuf;
424 BUG_ON(gss_msg->msg.len > UPCALL_BUF_LEN);
425}
426
427static void gss_encode_msg(struct gss_upcall_msg *gss_msg,
428 struct rpc_clnt *clnt,
429 const char *service_name)
430{
431 if (pipe_version == 0)
432 gss_encode_v0_msg(gss_msg);
433 else /* pipe_version == 1 */
434 gss_encode_v1_msg(gss_msg, clnt, service_name);
435}
436
437static struct gss_upcall_msg *
438gss_alloc_msg(struct gss_auth *gss_auth, struct rpc_clnt *clnt,
439 uid_t uid, const char *service_name)
440{
441 struct gss_upcall_msg *gss_msg;
442 int vers;
443
444 gss_msg = kzalloc(sizeof(*gss_msg), GFP_NOFS);
445 if (gss_msg == NULL)
446 return ERR_PTR(-ENOMEM);
447 vers = get_pipe_version();
448 if (vers < 0) {
449 kfree(gss_msg);
450 return ERR_PTR(vers);
451 }
452 gss_msg->pipe = gss_auth->pipe[vers];
453 INIT_LIST_HEAD(&gss_msg->list);
454 rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq");
455 init_waitqueue_head(&gss_msg->waitqueue);
456 atomic_set(&gss_msg->count, 1);
457 gss_msg->uid = uid;
458 gss_msg->auth = gss_auth;
459 gss_encode_msg(gss_msg, clnt, service_name);
460 return gss_msg;
461}
462
463static struct gss_upcall_msg *
464gss_setup_upcall(struct rpc_clnt *clnt, struct gss_auth *gss_auth, struct rpc_cred *cred)
465{
466 struct gss_cred *gss_cred = container_of(cred,
467 struct gss_cred, gc_base);
468 struct gss_upcall_msg *gss_new, *gss_msg;
469 uid_t uid = cred->cr_uid;
470
471 gss_new = gss_alloc_msg(gss_auth, clnt, uid, gss_cred->gc_principal);
472 if (IS_ERR(gss_new))
473 return gss_new;
474 gss_msg = gss_add_msg(gss_new);
475 if (gss_msg == gss_new) {
476 int res = rpc_queue_upcall(gss_new->pipe, &gss_new->msg);
477 if (res) {
478 gss_unhash_msg(gss_new);
479 gss_msg = ERR_PTR(res);
480 }
481 } else
482 gss_release_msg(gss_new);
483 return gss_msg;
484}
485
486static void warn_gssd(void)
487{
488 static unsigned long ratelimit;
489 unsigned long now = jiffies;
490
491 if (time_after(now, ratelimit)) {
492 printk(KERN_WARNING "RPC: AUTH_GSS upcall timed out.\n"
493 "Please check user daemon is running.\n");
494 ratelimit = now + 15*HZ;
495 }
496}
497
498static inline int
499gss_refresh_upcall(struct rpc_task *task)
500{
501 struct rpc_cred *cred = task->tk_rqstp->rq_cred;
502 struct gss_auth *gss_auth = container_of(cred->cr_auth,
503 struct gss_auth, rpc_auth);
504 struct gss_cred *gss_cred = container_of(cred,
505 struct gss_cred, gc_base);
506 struct gss_upcall_msg *gss_msg;
507 struct rpc_pipe *pipe;
508 int err = 0;
509
510 dprintk("RPC: %5u gss_refresh_upcall for uid %u\n", task->tk_pid,
511 cred->cr_uid);
512 gss_msg = gss_setup_upcall(task->tk_client, gss_auth, cred);
513 if (PTR_ERR(gss_msg) == -EAGAIN) {
514 /* XXX: warning on the first, under the assumption we
515 * shouldn't normally hit this case on a refresh. */
516 warn_gssd();
517 task->tk_timeout = 15*HZ;
518 rpc_sleep_on(&pipe_version_rpc_waitqueue, task, NULL);
519 return -EAGAIN;
520 }
521 if (IS_ERR(gss_msg)) {
522 err = PTR_ERR(gss_msg);
523 goto out;
524 }
525 pipe = gss_msg->pipe;
526 spin_lock(&pipe->lock);
527 if (gss_cred->gc_upcall != NULL)
528 rpc_sleep_on(&gss_cred->gc_upcall->rpc_waitqueue, task, NULL);
529 else if (gss_msg->ctx == NULL && gss_msg->msg.errno >= 0) {
530 task->tk_timeout = 0;
531 gss_cred->gc_upcall = gss_msg;
532 /* gss_upcall_callback will release the reference to gss_upcall_msg */
533 atomic_inc(&gss_msg->count);
534 rpc_sleep_on(&gss_msg->rpc_waitqueue, task, gss_upcall_callback);
535 } else {
536 gss_handle_downcall_result(gss_cred, gss_msg);
537 err = gss_msg->msg.errno;
538 }
539 spin_unlock(&pipe->lock);
540 gss_release_msg(gss_msg);
541out:
542 dprintk("RPC: %5u gss_refresh_upcall for uid %u result %d\n",
543 task->tk_pid, cred->cr_uid, err);
544 return err;
545}
546
547static inline int
548gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred)
549{
550 struct rpc_pipe *pipe;
551 struct rpc_cred *cred = &gss_cred->gc_base;
552 struct gss_upcall_msg *gss_msg;
553 DEFINE_WAIT(wait);
554 int err = 0;
555
556 dprintk("RPC: gss_upcall for uid %u\n", cred->cr_uid);
557retry:
558 gss_msg = gss_setup_upcall(gss_auth->client, gss_auth, cred);
559 if (PTR_ERR(gss_msg) == -EAGAIN) {
560 err = wait_event_interruptible_timeout(pipe_version_waitqueue,
561 pipe_version >= 0, 15*HZ);
562 if (pipe_version < 0) {
563 warn_gssd();
564 err = -EACCES;
565 }
566 if (err)
567 goto out;
568 goto retry;
569 }
570 if (IS_ERR(gss_msg)) {
571 err = PTR_ERR(gss_msg);
572 goto out;
573 }
574 pipe = gss_msg->pipe;
575 for (;;) {
576 prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_KILLABLE);
577 spin_lock(&pipe->lock);
578 if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) {
579 break;
580 }
581 spin_unlock(&pipe->lock);
582 if (fatal_signal_pending(current)) {
583 err = -ERESTARTSYS;
584 goto out_intr;
585 }
586 schedule();
587 }
588 if (gss_msg->ctx)
589 gss_cred_set_ctx(cred, gss_msg->ctx);
590 else
591 err = gss_msg->msg.errno;
592 spin_unlock(&pipe->lock);
593out_intr:
594 finish_wait(&gss_msg->waitqueue, &wait);
595 gss_release_msg(gss_msg);
596out:
597 dprintk("RPC: gss_create_upcall for uid %u result %d\n",
598 cred->cr_uid, err);
599 return err;
600}
601
602#define MSG_BUF_MAXSIZE 1024
603
604static ssize_t
605gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
606{
607 const void *p, *end;
608 void *buf;
609 struct gss_upcall_msg *gss_msg;
610 struct rpc_pipe *pipe = RPC_I(filp->f_dentry->d_inode)->pipe;
611 struct gss_cl_ctx *ctx;
612 uid_t uid;
613 ssize_t err = -EFBIG;
614
615 if (mlen > MSG_BUF_MAXSIZE)
616 goto out;
617 err = -ENOMEM;
618 buf = kmalloc(mlen, GFP_NOFS);
619 if (!buf)
620 goto out;
621
622 err = -EFAULT;
623 if (copy_from_user(buf, src, mlen))
624 goto err;
625
626 end = (const void *)((char *)buf + mlen);
627 p = simple_get_bytes(buf, end, &uid, sizeof(uid));
628 if (IS_ERR(p)) {
629 err = PTR_ERR(p);
630 goto err;
631 }
632
633 err = -ENOMEM;
634 ctx = gss_alloc_context();
635 if (ctx == NULL)
636 goto err;
637
638 err = -ENOENT;
639 /* Find a matching upcall */
640 spin_lock(&pipe->lock);
641 gss_msg = __gss_find_upcall(pipe, uid);
642 if (gss_msg == NULL) {
643 spin_unlock(&pipe->lock);
644 goto err_put_ctx;
645 }
646 list_del_init(&gss_msg->list);
647 spin_unlock(&pipe->lock);
648
649 p = gss_fill_context(p, end, ctx, gss_msg->auth->mech);
650 if (IS_ERR(p)) {
651 err = PTR_ERR(p);
652 switch (err) {
653 case -EACCES:
654 case -EKEYEXPIRED:
655 gss_msg->msg.errno = err;
656 err = mlen;
657 break;
658 case -EFAULT:
659 case -ENOMEM:
660 case -EINVAL:
661 case -ENOSYS:
662 gss_msg->msg.errno = -EAGAIN;
663 break;
664 default:
665 printk(KERN_CRIT "%s: bad return from "
666 "gss_fill_context: %zd\n", __func__, err);
667 BUG();
668 }
669 goto err_release_msg;
670 }
671 gss_msg->ctx = gss_get_ctx(ctx);
672 err = mlen;
673
674err_release_msg:
675 spin_lock(&pipe->lock);
676 __gss_unhash_msg(gss_msg);
677 spin_unlock(&pipe->lock);
678 gss_release_msg(gss_msg);
679err_put_ctx:
680 gss_put_ctx(ctx);
681err:
682 kfree(buf);
683out:
684 dprintk("RPC: gss_pipe_downcall returning %Zd\n", err);
685 return err;
686}
687
688static int gss_pipe_open(struct inode *inode, int new_version)
689{
690 int ret = 0;
691
692 spin_lock(&pipe_version_lock);
693 if (pipe_version < 0) {
694 /* First open of any gss pipe determines the version: */
695 pipe_version = new_version;
696 rpc_wake_up(&pipe_version_rpc_waitqueue);
697 wake_up(&pipe_version_waitqueue);
698 } else if (pipe_version != new_version) {
699 /* Trying to open a pipe of a different version */
700 ret = -EBUSY;
701 goto out;
702 }
703 atomic_inc(&pipe_users);
704out:
705 spin_unlock(&pipe_version_lock);
706 return ret;
707
708}
709
710static int gss_pipe_open_v0(struct inode *inode)
711{
712 return gss_pipe_open(inode, 0);
713}
714
715static int gss_pipe_open_v1(struct inode *inode)
716{
717 return gss_pipe_open(inode, 1);
718}
719
720static void
721gss_pipe_release(struct inode *inode)
722{
723 struct rpc_pipe *pipe = RPC_I(inode)->pipe;
724 struct gss_upcall_msg *gss_msg;
725
726restart:
727 spin_lock(&pipe->lock);
728 list_for_each_entry(gss_msg, &pipe->in_downcall, list) {
729
730 if (!list_empty(&gss_msg->msg.list))
731 continue;
732 gss_msg->msg.errno = -EPIPE;
733 atomic_inc(&gss_msg->count);
734 __gss_unhash_msg(gss_msg);
735 spin_unlock(&pipe->lock);
736 gss_release_msg(gss_msg);
737 goto restart;
738 }
739 spin_unlock(&pipe->lock);
740
741 put_pipe_version();
742}
743
744static void
745gss_pipe_destroy_msg(struct rpc_pipe_msg *msg)
746{
747 struct gss_upcall_msg *gss_msg = container_of(msg, struct gss_upcall_msg, msg);
748
749 if (msg->errno < 0) {
750 dprintk("RPC: gss_pipe_destroy_msg releasing msg %p\n",
751 gss_msg);
752 atomic_inc(&gss_msg->count);
753 gss_unhash_msg(gss_msg);
754 if (msg->errno == -ETIMEDOUT)
755 warn_gssd();
756 gss_release_msg(gss_msg);
757 }
758}
759
760static void gss_pipes_dentries_destroy(struct rpc_auth *auth)
761{
762 struct gss_auth *gss_auth;
763
764 gss_auth = container_of(auth, struct gss_auth, rpc_auth);
765 if (gss_auth->pipe[0]->dentry)
766 rpc_unlink(gss_auth->pipe[0]->dentry);
767 if (gss_auth->pipe[1]->dentry)
768 rpc_unlink(gss_auth->pipe[1]->dentry);
769}
770
771static int gss_pipes_dentries_create(struct rpc_auth *auth)
772{
773 int err;
774 struct gss_auth *gss_auth;
775 struct rpc_clnt *clnt;
776
777 gss_auth = container_of(auth, struct gss_auth, rpc_auth);
778 clnt = gss_auth->client;
779
780 gss_auth->pipe[1]->dentry = rpc_mkpipe_dentry(clnt->cl_dentry,
781 "gssd",
782 clnt, gss_auth->pipe[1]);
783 if (IS_ERR(gss_auth->pipe[1]->dentry))
784 return PTR_ERR(gss_auth->pipe[1]->dentry);
785 gss_auth->pipe[0]->dentry = rpc_mkpipe_dentry(clnt->cl_dentry,
786 gss_auth->mech->gm_name,
787 clnt, gss_auth->pipe[0]);
788 if (IS_ERR(gss_auth->pipe[0]->dentry)) {
789 err = PTR_ERR(gss_auth->pipe[0]->dentry);
790 goto err_unlink_pipe_1;
791 }
792 return 0;
793
794err_unlink_pipe_1:
795 rpc_unlink(gss_auth->pipe[1]->dentry);
796 return err;
797}
798
799static void gss_pipes_dentries_destroy_net(struct rpc_clnt *clnt,
800 struct rpc_auth *auth)
801{
802 struct net *net = rpc_net_ns(clnt);
803 struct super_block *sb;
804
805 sb = rpc_get_sb_net(net);
806 if (sb) {
807 if (clnt->cl_dentry)
808 gss_pipes_dentries_destroy(auth);
809 rpc_put_sb_net(net);
810 }
811}
812
813static int gss_pipes_dentries_create_net(struct rpc_clnt *clnt,
814 struct rpc_auth *auth)
815{
816 struct net *net = rpc_net_ns(clnt);
817 struct super_block *sb;
818 int err = 0;
819
820 sb = rpc_get_sb_net(net);
821 if (sb) {
822 if (clnt->cl_dentry)
823 err = gss_pipes_dentries_create(auth);
824 rpc_put_sb_net(net);
825 }
826 return err;
827}
828
829/*
830 * NOTE: we have the opportunity to use different
831 * parameters based on the input flavor (which must be a pseudoflavor)
832 */
833static struct rpc_auth *
834gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
835{
836 struct gss_auth *gss_auth;
837 struct rpc_auth * auth;
838 int err = -ENOMEM; /* XXX? */
839
840 dprintk("RPC: creating GSS authenticator for client %p\n", clnt);
841
842 if (!try_module_get(THIS_MODULE))
843 return ERR_PTR(err);
844 if (!(gss_auth = kmalloc(sizeof(*gss_auth), GFP_KERNEL)))
845 goto out_dec;
846 gss_auth->client = clnt;
847 err = -EINVAL;
848 gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor);
849 if (!gss_auth->mech) {
850 printk(KERN_WARNING "%s: Pseudoflavor %d not found!\n",
851 __func__, flavor);
852 goto err_free;
853 }
854 gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor);
855 if (gss_auth->service == 0)
856 goto err_put_mech;
857 auth = &gss_auth->rpc_auth;
858 auth->au_cslack = GSS_CRED_SLACK >> 2;
859 auth->au_rslack = GSS_VERF_SLACK >> 2;
860 auth->au_ops = &authgss_ops;
861 auth->au_flavor = flavor;
862 atomic_set(&auth->au_count, 1);
863 kref_init(&gss_auth->kref);
864
865 /*
866 * Note: if we created the old pipe first, then someone who
867 * examined the directory at the right moment might conclude
868 * that we supported only the old pipe. So we instead create
869 * the new pipe first.
870 */
871 gss_auth->pipe[1] = rpc_mkpipe_data(&gss_upcall_ops_v1,
872 RPC_PIPE_WAIT_FOR_OPEN);
873 if (IS_ERR(gss_auth->pipe[1])) {
874 err = PTR_ERR(gss_auth->pipe[1]);
875 goto err_put_mech;
876 }
877
878 gss_auth->pipe[0] = rpc_mkpipe_data(&gss_upcall_ops_v0,
879 RPC_PIPE_WAIT_FOR_OPEN);
880 if (IS_ERR(gss_auth->pipe[0])) {
881 err = PTR_ERR(gss_auth->pipe[0]);
882 goto err_destroy_pipe_1;
883 }
884 err = gss_pipes_dentries_create_net(clnt, auth);
885 if (err)
886 goto err_destroy_pipe_0;
887 err = rpcauth_init_credcache(auth);
888 if (err)
889 goto err_unlink_pipes;
890
891 return auth;
892err_unlink_pipes:
893 gss_pipes_dentries_destroy_net(clnt, auth);
894err_destroy_pipe_0:
895 rpc_destroy_pipe_data(gss_auth->pipe[0]);
896err_destroy_pipe_1:
897 rpc_destroy_pipe_data(gss_auth->pipe[1]);
898err_put_mech:
899 gss_mech_put(gss_auth->mech);
900err_free:
901 kfree(gss_auth);
902out_dec:
903 module_put(THIS_MODULE);
904 return ERR_PTR(err);
905}
906
907static void
908gss_free(struct gss_auth *gss_auth)
909{
910 gss_pipes_dentries_destroy_net(gss_auth->client, &gss_auth->rpc_auth);
911 rpc_destroy_pipe_data(gss_auth->pipe[0]);
912 rpc_destroy_pipe_data(gss_auth->pipe[1]);
913 gss_mech_put(gss_auth->mech);
914
915 kfree(gss_auth);
916 module_put(THIS_MODULE);
917}
918
919static void
920gss_free_callback(struct kref *kref)
921{
922 struct gss_auth *gss_auth = container_of(kref, struct gss_auth, kref);
923
924 gss_free(gss_auth);
925}
926
927static void
928gss_destroy(struct rpc_auth *auth)
929{
930 struct gss_auth *gss_auth;
931
932 dprintk("RPC: destroying GSS authenticator %p flavor %d\n",
933 auth, auth->au_flavor);
934
935 rpcauth_destroy_credcache(auth);
936
937 gss_auth = container_of(auth, struct gss_auth, rpc_auth);
938 kref_put(&gss_auth->kref, gss_free_callback);
939}
940
941/*
942 * gss_destroying_context will cause the RPCSEC_GSS to send a NULL RPC call
943 * to the server with the GSS control procedure field set to
944 * RPC_GSS_PROC_DESTROY. This should normally cause the server to release
945 * all RPCSEC_GSS state associated with that context.
946 */
947static int
948gss_destroying_context(struct rpc_cred *cred)
949{
950 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
951 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth);
952 struct rpc_task *task;
953
954 if (gss_cred->gc_ctx == NULL ||
955 test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0)
956 return 0;
957
958 gss_cred->gc_ctx->gc_proc = RPC_GSS_PROC_DESTROY;
959 cred->cr_ops = &gss_nullops;
960
961 /* Take a reference to ensure the cred will be destroyed either
962 * by the RPC call or by the put_rpccred() below */
963 get_rpccred(cred);
964
965 task = rpc_call_null(gss_auth->client, cred, RPC_TASK_ASYNC|RPC_TASK_SOFT);
966 if (!IS_ERR(task))
967 rpc_put_task(task);
968
969 put_rpccred(cred);
970 return 1;
971}
972
973/* gss_destroy_cred (and gss_free_ctx) are used to clean up after failure
974 * to create a new cred or context, so they check that things have been
975 * allocated before freeing them. */
976static void
977gss_do_free_ctx(struct gss_cl_ctx *ctx)
978{
979 dprintk("RPC: gss_free_ctx\n");
980
981 gss_delete_sec_context(&ctx->gc_gss_ctx);
982 kfree(ctx->gc_wire_ctx.data);
983 kfree(ctx);
984}
985
986static void
987gss_free_ctx_callback(struct rcu_head *head)
988{
989 struct gss_cl_ctx *ctx = container_of(head, struct gss_cl_ctx, gc_rcu);
990 gss_do_free_ctx(ctx);
991}
992
993static void
994gss_free_ctx(struct gss_cl_ctx *ctx)
995{
996 call_rcu(&ctx->gc_rcu, gss_free_ctx_callback);
997}
998
999static void
1000gss_free_cred(struct gss_cred *gss_cred)
1001{
1002 dprintk("RPC: gss_free_cred %p\n", gss_cred);
1003 kfree(gss_cred);
1004}
1005
1006static void
1007gss_free_cred_callback(struct rcu_head *head)
1008{
1009 struct gss_cred *gss_cred = container_of(head, struct gss_cred, gc_base.cr_rcu);
1010 gss_free_cred(gss_cred);
1011}
1012
1013static void
1014gss_destroy_nullcred(struct rpc_cred *cred)
1015{
1016 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
1017 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth);
1018 struct gss_cl_ctx *ctx = gss_cred->gc_ctx;
1019
1020 RCU_INIT_POINTER(gss_cred->gc_ctx, NULL);
1021 call_rcu(&cred->cr_rcu, gss_free_cred_callback);
1022 if (ctx)
1023 gss_put_ctx(ctx);
1024 kref_put(&gss_auth->kref, gss_free_callback);
1025}
1026
1027static void
1028gss_destroy_cred(struct rpc_cred *cred)
1029{
1030
1031 if (gss_destroying_context(cred))
1032 return;
1033 gss_destroy_nullcred(cred);
1034}
1035
1036/*
1037 * Lookup RPCSEC_GSS cred for the current process
1038 */
1039static struct rpc_cred *
1040gss_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
1041{
1042 return rpcauth_lookup_credcache(auth, acred, flags);
1043}
1044
1045static struct rpc_cred *
1046gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
1047{
1048 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth);
1049 struct gss_cred *cred = NULL;
1050 int err = -ENOMEM;
1051
1052 dprintk("RPC: gss_create_cred for uid %d, flavor %d\n",
1053 acred->uid, auth->au_flavor);
1054
1055 if (!(cred = kzalloc(sizeof(*cred), GFP_NOFS)))
1056 goto out_err;
1057
1058 rpcauth_init_cred(&cred->gc_base, acred, auth, &gss_credops);
1059 /*
1060 * Note: in order to force a call to call_refresh(), we deliberately
1061 * fail to flag the credential as RPCAUTH_CRED_UPTODATE.
1062 */
1063 cred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_NEW;
1064 cred->gc_service = gss_auth->service;
1065 cred->gc_principal = NULL;
1066 if (acred->machine_cred)
1067 cred->gc_principal = acred->principal;
1068 kref_get(&gss_auth->kref);
1069 return &cred->gc_base;
1070
1071out_err:
1072 dprintk("RPC: gss_create_cred failed with error %d\n", err);
1073 return ERR_PTR(err);
1074}
1075
1076static int
1077gss_cred_init(struct rpc_auth *auth, struct rpc_cred *cred)
1078{
1079 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth);
1080 struct gss_cred *gss_cred = container_of(cred,struct gss_cred, gc_base);
1081 int err;
1082
1083 do {
1084 err = gss_create_upcall(gss_auth, gss_cred);
1085 } while (err == -EAGAIN);
1086 return err;
1087}
1088
1089static int
1090gss_match(struct auth_cred *acred, struct rpc_cred *rc, int flags)
1091{
1092 struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base);
1093
1094 if (test_bit(RPCAUTH_CRED_NEW, &rc->cr_flags))
1095 goto out;
1096 /* Don't match with creds that have expired. */
1097 if (time_after(jiffies, gss_cred->gc_ctx->gc_expiry))
1098 return 0;
1099 if (!test_bit(RPCAUTH_CRED_UPTODATE, &rc->cr_flags))
1100 return 0;
1101out:
1102 if (acred->principal != NULL) {
1103 if (gss_cred->gc_principal == NULL)
1104 return 0;
1105 return strcmp(acred->principal, gss_cred->gc_principal) == 0;
1106 }
1107 if (gss_cred->gc_principal != NULL)
1108 return 0;
1109 return rc->cr_uid == acred->uid;
1110}
1111
1112/*
1113* Marshal credentials.
1114* Maybe we should keep a cached credential for performance reasons.
1115*/
1116static __be32 *
1117gss_marshal(struct rpc_task *task, __be32 *p)
1118{
1119 struct rpc_rqst *req = task->tk_rqstp;
1120 struct rpc_cred *cred = req->rq_cred;
1121 struct gss_cred *gss_cred = container_of(cred, struct gss_cred,
1122 gc_base);
1123 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred);
1124 __be32 *cred_len;
1125 u32 maj_stat = 0;
1126 struct xdr_netobj mic;
1127 struct kvec iov;
1128 struct xdr_buf verf_buf;
1129
1130 dprintk("RPC: %5u gss_marshal\n", task->tk_pid);
1131
1132 *p++ = htonl(RPC_AUTH_GSS);
1133 cred_len = p++;
1134
1135 spin_lock(&ctx->gc_seq_lock);
1136 req->rq_seqno = ctx->gc_seq++;
1137 spin_unlock(&ctx->gc_seq_lock);
1138
1139 *p++ = htonl((u32) RPC_GSS_VERSION);
1140 *p++ = htonl((u32) ctx->gc_proc);
1141 *p++ = htonl((u32) req->rq_seqno);
1142 *p++ = htonl((u32) gss_cred->gc_service);
1143 p = xdr_encode_netobj(p, &ctx->gc_wire_ctx);
1144 *cred_len = htonl((p - (cred_len + 1)) << 2);
1145
1146 /* We compute the checksum for the verifier over the xdr-encoded bytes
1147 * starting with the xid and ending at the end of the credential: */
1148 iov.iov_base = xprt_skip_transport_header(task->tk_xprt,
1149 req->rq_snd_buf.head[0].iov_base);
1150 iov.iov_len = (u8 *)p - (u8 *)iov.iov_base;
1151 xdr_buf_from_iov(&iov, &verf_buf);
1152
1153 /* set verifier flavor*/
1154 *p++ = htonl(RPC_AUTH_GSS);
1155
1156 mic.data = (u8 *)(p + 1);
1157 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &verf_buf, &mic);
1158 if (maj_stat == GSS_S_CONTEXT_EXPIRED) {
1159 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
1160 } else if (maj_stat != 0) {
1161 printk("gss_marshal: gss_get_mic FAILED (%d)\n", maj_stat);
1162 goto out_put_ctx;
1163 }
1164 p = xdr_encode_opaque(p, NULL, mic.len);
1165 gss_put_ctx(ctx);
1166 return p;
1167out_put_ctx:
1168 gss_put_ctx(ctx);
1169 return NULL;
1170}
1171
1172static int gss_renew_cred(struct rpc_task *task)
1173{
1174 struct rpc_cred *oldcred = task->tk_rqstp->rq_cred;
1175 struct gss_cred *gss_cred = container_of(oldcred,
1176 struct gss_cred,
1177 gc_base);
1178 struct rpc_auth *auth = oldcred->cr_auth;
1179 struct auth_cred acred = {
1180 .uid = oldcred->cr_uid,
1181 .principal = gss_cred->gc_principal,
1182 .machine_cred = (gss_cred->gc_principal != NULL ? 1 : 0),
1183 };
1184 struct rpc_cred *new;
1185
1186 new = gss_lookup_cred(auth, &acred, RPCAUTH_LOOKUP_NEW);
1187 if (IS_ERR(new))
1188 return PTR_ERR(new);
1189 task->tk_rqstp->rq_cred = new;
1190 put_rpccred(oldcred);
1191 return 0;
1192}
1193
1194static int gss_cred_is_negative_entry(struct rpc_cred *cred)
1195{
1196 if (test_bit(RPCAUTH_CRED_NEGATIVE, &cred->cr_flags)) {
1197 unsigned long now = jiffies;
1198 unsigned long begin, expire;
1199 struct gss_cred *gss_cred;
1200
1201 gss_cred = container_of(cred, struct gss_cred, gc_base);
1202 begin = gss_cred->gc_upcall_timestamp;
1203 expire = begin + gss_expired_cred_retry_delay * HZ;
1204
1205 if (time_in_range_open(now, begin, expire))
1206 return 1;
1207 }
1208 return 0;
1209}
1210
1211/*
1212* Refresh credentials. XXX - finish
1213*/
1214static int
1215gss_refresh(struct rpc_task *task)
1216{
1217 struct rpc_cred *cred = task->tk_rqstp->rq_cred;
1218 int ret = 0;
1219
1220 if (gss_cred_is_negative_entry(cred))
1221 return -EKEYEXPIRED;
1222
1223 if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) &&
1224 !test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags)) {
1225 ret = gss_renew_cred(task);
1226 if (ret < 0)
1227 goto out;
1228 cred = task->tk_rqstp->rq_cred;
1229 }
1230
1231 if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags))
1232 ret = gss_refresh_upcall(task);
1233out:
1234 return ret;
1235}
1236
1237/* Dummy refresh routine: used only when destroying the context */
1238static int
1239gss_refresh_null(struct rpc_task *task)
1240{
1241 return -EACCES;
1242}
1243
1244static __be32 *
1245gss_validate(struct rpc_task *task, __be32 *p)
1246{
1247 struct rpc_cred *cred = task->tk_rqstp->rq_cred;
1248 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred);
1249 __be32 seq;
1250 struct kvec iov;
1251 struct xdr_buf verf_buf;
1252 struct xdr_netobj mic;
1253 u32 flav,len;
1254 u32 maj_stat;
1255
1256 dprintk("RPC: %5u gss_validate\n", task->tk_pid);
1257
1258 flav = ntohl(*p++);
1259 if ((len = ntohl(*p++)) > RPC_MAX_AUTH_SIZE)
1260 goto out_bad;
1261 if (flav != RPC_AUTH_GSS)
1262 goto out_bad;
1263 seq = htonl(task->tk_rqstp->rq_seqno);
1264 iov.iov_base = &seq;
1265 iov.iov_len = sizeof(seq);
1266 xdr_buf_from_iov(&iov, &verf_buf);
1267 mic.data = (u8 *)p;
1268 mic.len = len;
1269
1270 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic);
1271 if (maj_stat == GSS_S_CONTEXT_EXPIRED)
1272 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
1273 if (maj_stat) {
1274 dprintk("RPC: %5u gss_validate: gss_verify_mic returned "
1275 "error 0x%08x\n", task->tk_pid, maj_stat);
1276 goto out_bad;
1277 }
1278 /* We leave it to unwrap to calculate au_rslack. For now we just
1279 * calculate the length of the verifier: */
1280 cred->cr_auth->au_verfsize = XDR_QUADLEN(len) + 2;
1281 gss_put_ctx(ctx);
1282 dprintk("RPC: %5u gss_validate: gss_verify_mic succeeded.\n",
1283 task->tk_pid);
1284 return p + XDR_QUADLEN(len);
1285out_bad:
1286 gss_put_ctx(ctx);
1287 dprintk("RPC: %5u gss_validate failed.\n", task->tk_pid);
1288 return NULL;
1289}
1290
1291static void gss_wrap_req_encode(kxdreproc_t encode, struct rpc_rqst *rqstp,
1292 __be32 *p, void *obj)
1293{
1294 struct xdr_stream xdr;
1295
1296 xdr_init_encode(&xdr, &rqstp->rq_snd_buf, p);
1297 encode(rqstp, &xdr, obj);
1298}
1299
1300static inline int
1301gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
1302 kxdreproc_t encode, struct rpc_rqst *rqstp,
1303 __be32 *p, void *obj)
1304{
1305 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf;
1306 struct xdr_buf integ_buf;
1307 __be32 *integ_len = NULL;
1308 struct xdr_netobj mic;
1309 u32 offset;
1310 __be32 *q;
1311 struct kvec *iov;
1312 u32 maj_stat = 0;
1313 int status = -EIO;
1314
1315 integ_len = p++;
1316 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base;
1317 *p++ = htonl(rqstp->rq_seqno);
1318
1319 gss_wrap_req_encode(encode, rqstp, p, obj);
1320
1321 if (xdr_buf_subsegment(snd_buf, &integ_buf,
1322 offset, snd_buf->len - offset))
1323 return status;
1324 *integ_len = htonl(integ_buf.len);
1325
1326 /* guess whether we're in the head or the tail: */
1327 if (snd_buf->page_len || snd_buf->tail[0].iov_len)
1328 iov = snd_buf->tail;
1329 else
1330 iov = snd_buf->head;
1331 p = iov->iov_base + iov->iov_len;
1332 mic.data = (u8 *)(p + 1);
1333
1334 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &integ_buf, &mic);
1335 status = -EIO; /* XXX? */
1336 if (maj_stat == GSS_S_CONTEXT_EXPIRED)
1337 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
1338 else if (maj_stat)
1339 return status;
1340 q = xdr_encode_opaque(p, NULL, mic.len);
1341
1342 offset = (u8 *)q - (u8 *)p;
1343 iov->iov_len += offset;
1344 snd_buf->len += offset;
1345 return 0;
1346}
1347
1348static void
1349priv_release_snd_buf(struct rpc_rqst *rqstp)
1350{
1351 int i;
1352
1353 for (i=0; i < rqstp->rq_enc_pages_num; i++)
1354 __free_page(rqstp->rq_enc_pages[i]);
1355 kfree(rqstp->rq_enc_pages);
1356}
1357
1358static int
1359alloc_enc_pages(struct rpc_rqst *rqstp)
1360{
1361 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf;
1362 int first, last, i;
1363
1364 if (snd_buf->page_len == 0) {
1365 rqstp->rq_enc_pages_num = 0;
1366 return 0;
1367 }
1368
1369 first = snd_buf->page_base >> PAGE_CACHE_SHIFT;
1370 last = (snd_buf->page_base + snd_buf->page_len - 1) >> PAGE_CACHE_SHIFT;
1371 rqstp->rq_enc_pages_num = last - first + 1 + 1;
1372 rqstp->rq_enc_pages
1373 = kmalloc(rqstp->rq_enc_pages_num * sizeof(struct page *),
1374 GFP_NOFS);
1375 if (!rqstp->rq_enc_pages)
1376 goto out;
1377 for (i=0; i < rqstp->rq_enc_pages_num; i++) {
1378 rqstp->rq_enc_pages[i] = alloc_page(GFP_NOFS);
1379 if (rqstp->rq_enc_pages[i] == NULL)
1380 goto out_free;
1381 }
1382 rqstp->rq_release_snd_buf = priv_release_snd_buf;
1383 return 0;
1384out_free:
1385 rqstp->rq_enc_pages_num = i;
1386 priv_release_snd_buf(rqstp);
1387out:
1388 return -EAGAIN;
1389}
1390
1391static inline int
1392gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
1393 kxdreproc_t encode, struct rpc_rqst *rqstp,
1394 __be32 *p, void *obj)
1395{
1396 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf;
1397 u32 offset;
1398 u32 maj_stat;
1399 int status;
1400 __be32 *opaque_len;
1401 struct page **inpages;
1402 int first;
1403 int pad;
1404 struct kvec *iov;
1405 char *tmp;
1406
1407 opaque_len = p++;
1408 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base;
1409 *p++ = htonl(rqstp->rq_seqno);
1410
1411 gss_wrap_req_encode(encode, rqstp, p, obj);
1412
1413 status = alloc_enc_pages(rqstp);
1414 if (status)
1415 return status;
1416 first = snd_buf->page_base >> PAGE_CACHE_SHIFT;
1417 inpages = snd_buf->pages + first;
1418 snd_buf->pages = rqstp->rq_enc_pages;
1419 snd_buf->page_base -= first << PAGE_CACHE_SHIFT;
1420 /*
1421 * Give the tail its own page, in case we need extra space in the
1422 * head when wrapping:
1423 *
1424 * call_allocate() allocates twice the slack space required
1425 * by the authentication flavor to rq_callsize.
1426 * For GSS, slack is GSS_CRED_SLACK.
1427 */
1428 if (snd_buf->page_len || snd_buf->tail[0].iov_len) {
1429 tmp = page_address(rqstp->rq_enc_pages[rqstp->rq_enc_pages_num - 1]);
1430 memcpy(tmp, snd_buf->tail[0].iov_base, snd_buf->tail[0].iov_len);
1431 snd_buf->tail[0].iov_base = tmp;
1432 }
1433 maj_stat = gss_wrap(ctx->gc_gss_ctx, offset, snd_buf, inpages);
1434 /* slack space should prevent this ever happening: */
1435 BUG_ON(snd_buf->len > snd_buf->buflen);
1436 status = -EIO;
1437 /* We're assuming that when GSS_S_CONTEXT_EXPIRED, the encryption was
1438 * done anyway, so it's safe to put the request on the wire: */
1439 if (maj_stat == GSS_S_CONTEXT_EXPIRED)
1440 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
1441 else if (maj_stat)
1442 return status;
1443
1444 *opaque_len = htonl(snd_buf->len - offset);
1445 /* guess whether we're in the head or the tail: */
1446 if (snd_buf->page_len || snd_buf->tail[0].iov_len)
1447 iov = snd_buf->tail;
1448 else
1449 iov = snd_buf->head;
1450 p = iov->iov_base + iov->iov_len;
1451 pad = 3 - ((snd_buf->len - offset - 1) & 3);
1452 memset(p, 0, pad);
1453 iov->iov_len += pad;
1454 snd_buf->len += pad;
1455
1456 return 0;
1457}
1458
1459static int
1460gss_wrap_req(struct rpc_task *task,
1461 kxdreproc_t encode, void *rqstp, __be32 *p, void *obj)
1462{
1463 struct rpc_cred *cred = task->tk_rqstp->rq_cred;
1464 struct gss_cred *gss_cred = container_of(cred, struct gss_cred,
1465 gc_base);
1466 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred);
1467 int status = -EIO;
1468
1469 dprintk("RPC: %5u gss_wrap_req\n", task->tk_pid);
1470 if (ctx->gc_proc != RPC_GSS_PROC_DATA) {
1471 /* The spec seems a little ambiguous here, but I think that not
1472 * wrapping context destruction requests makes the most sense.
1473 */
1474 gss_wrap_req_encode(encode, rqstp, p, obj);
1475 status = 0;
1476 goto out;
1477 }
1478 switch (gss_cred->gc_service) {
1479 case RPC_GSS_SVC_NONE:
1480 gss_wrap_req_encode(encode, rqstp, p, obj);
1481 status = 0;
1482 break;
1483 case RPC_GSS_SVC_INTEGRITY:
1484 status = gss_wrap_req_integ(cred, ctx, encode, rqstp, p, obj);
1485 break;
1486 case RPC_GSS_SVC_PRIVACY:
1487 status = gss_wrap_req_priv(cred, ctx, encode, rqstp, p, obj);
1488 break;
1489 }
1490out:
1491 gss_put_ctx(ctx);
1492 dprintk("RPC: %5u gss_wrap_req returning %d\n", task->tk_pid, status);
1493 return status;
1494}
1495
1496static inline int
1497gss_unwrap_resp_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
1498 struct rpc_rqst *rqstp, __be32 **p)
1499{
1500 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf;
1501 struct xdr_buf integ_buf;
1502 struct xdr_netobj mic;
1503 u32 data_offset, mic_offset;
1504 u32 integ_len;
1505 u32 maj_stat;
1506 int status = -EIO;
1507
1508 integ_len = ntohl(*(*p)++);
1509 if (integ_len & 3)
1510 return status;
1511 data_offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base;
1512 mic_offset = integ_len + data_offset;
1513 if (mic_offset > rcv_buf->len)
1514 return status;
1515 if (ntohl(*(*p)++) != rqstp->rq_seqno)
1516 return status;
1517
1518 if (xdr_buf_subsegment(rcv_buf, &integ_buf, data_offset,
1519 mic_offset - data_offset))
1520 return status;
1521
1522 if (xdr_buf_read_netobj(rcv_buf, &mic, mic_offset))
1523 return status;
1524
1525 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &integ_buf, &mic);
1526 if (maj_stat == GSS_S_CONTEXT_EXPIRED)
1527 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
1528 if (maj_stat != GSS_S_COMPLETE)
1529 return status;
1530 return 0;
1531}
1532
1533static inline int
1534gss_unwrap_resp_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
1535 struct rpc_rqst *rqstp, __be32 **p)
1536{
1537 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf;
1538 u32 offset;
1539 u32 opaque_len;
1540 u32 maj_stat;
1541 int status = -EIO;
1542
1543 opaque_len = ntohl(*(*p)++);
1544 offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base;
1545 if (offset + opaque_len > rcv_buf->len)
1546 return status;
1547 /* remove padding: */
1548 rcv_buf->len = offset + opaque_len;
1549
1550 maj_stat = gss_unwrap(ctx->gc_gss_ctx, offset, rcv_buf);
1551 if (maj_stat == GSS_S_CONTEXT_EXPIRED)
1552 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
1553 if (maj_stat != GSS_S_COMPLETE)
1554 return status;
1555 if (ntohl(*(*p)++) != rqstp->rq_seqno)
1556 return status;
1557
1558 return 0;
1559}
1560
1561static int
1562gss_unwrap_req_decode(kxdrdproc_t decode, struct rpc_rqst *rqstp,
1563 __be32 *p, void *obj)
1564{
1565 struct xdr_stream xdr;
1566
1567 xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
1568 return decode(rqstp, &xdr, obj);
1569}
1570
1571static int
1572gss_unwrap_resp(struct rpc_task *task,
1573 kxdrdproc_t decode, void *rqstp, __be32 *p, void *obj)
1574{
1575 struct rpc_cred *cred = task->tk_rqstp->rq_cred;
1576 struct gss_cred *gss_cred = container_of(cred, struct gss_cred,
1577 gc_base);
1578 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred);
1579 __be32 *savedp = p;
1580 struct kvec *head = ((struct rpc_rqst *)rqstp)->rq_rcv_buf.head;
1581 int savedlen = head->iov_len;
1582 int status = -EIO;
1583
1584 if (ctx->gc_proc != RPC_GSS_PROC_DATA)
1585 goto out_decode;
1586 switch (gss_cred->gc_service) {
1587 case RPC_GSS_SVC_NONE:
1588 break;
1589 case RPC_GSS_SVC_INTEGRITY:
1590 status = gss_unwrap_resp_integ(cred, ctx, rqstp, &p);
1591 if (status)
1592 goto out;
1593 break;
1594 case RPC_GSS_SVC_PRIVACY:
1595 status = gss_unwrap_resp_priv(cred, ctx, rqstp, &p);
1596 if (status)
1597 goto out;
1598 break;
1599 }
1600 /* take into account extra slack for integrity and privacy cases: */
1601 cred->cr_auth->au_rslack = cred->cr_auth->au_verfsize + (p - savedp)
1602 + (savedlen - head->iov_len);
1603out_decode:
1604 status = gss_unwrap_req_decode(decode, rqstp, p, obj);
1605out:
1606 gss_put_ctx(ctx);
1607 dprintk("RPC: %5u gss_unwrap_resp returning %d\n", task->tk_pid,
1608 status);
1609 return status;
1610}
1611
1612static const struct rpc_authops authgss_ops = {
1613 .owner = THIS_MODULE,
1614 .au_flavor = RPC_AUTH_GSS,
1615 .au_name = "RPCSEC_GSS",
1616 .create = gss_create,
1617 .destroy = gss_destroy,
1618 .lookup_cred = gss_lookup_cred,
1619 .crcreate = gss_create_cred,
1620 .pipes_create = gss_pipes_dentries_create,
1621 .pipes_destroy = gss_pipes_dentries_destroy,
1622};
1623
1624static const struct rpc_credops gss_credops = {
1625 .cr_name = "AUTH_GSS",
1626 .crdestroy = gss_destroy_cred,
1627 .cr_init = gss_cred_init,
1628 .crbind = rpcauth_generic_bind_cred,
1629 .crmatch = gss_match,
1630 .crmarshal = gss_marshal,
1631 .crrefresh = gss_refresh,
1632 .crvalidate = gss_validate,
1633 .crwrap_req = gss_wrap_req,
1634 .crunwrap_resp = gss_unwrap_resp,
1635};
1636
1637static const struct rpc_credops gss_nullops = {
1638 .cr_name = "AUTH_GSS",
1639 .crdestroy = gss_destroy_nullcred,
1640 .crbind = rpcauth_generic_bind_cred,
1641 .crmatch = gss_match,
1642 .crmarshal = gss_marshal,
1643 .crrefresh = gss_refresh_null,
1644 .crvalidate = gss_validate,
1645 .crwrap_req = gss_wrap_req,
1646 .crunwrap_resp = gss_unwrap_resp,
1647};
1648
1649static const struct rpc_pipe_ops gss_upcall_ops_v0 = {
1650 .upcall = rpc_pipe_generic_upcall,
1651 .downcall = gss_pipe_downcall,
1652 .destroy_msg = gss_pipe_destroy_msg,
1653 .open_pipe = gss_pipe_open_v0,
1654 .release_pipe = gss_pipe_release,
1655};
1656
1657static const struct rpc_pipe_ops gss_upcall_ops_v1 = {
1658 .upcall = rpc_pipe_generic_upcall,
1659 .downcall = gss_pipe_downcall,
1660 .destroy_msg = gss_pipe_destroy_msg,
1661 .open_pipe = gss_pipe_open_v1,
1662 .release_pipe = gss_pipe_release,
1663};
1664
1665static __net_init int rpcsec_gss_init_net(struct net *net)
1666{
1667 return gss_svc_init_net(net);
1668}
1669
1670static __net_exit void rpcsec_gss_exit_net(struct net *net)
1671{
1672 gss_svc_shutdown_net(net);
1673}
1674
1675static struct pernet_operations rpcsec_gss_net_ops = {
1676 .init = rpcsec_gss_init_net,
1677 .exit = rpcsec_gss_exit_net,
1678};
1679
1680/*
1681 * Initialize RPCSEC_GSS module
1682 */
1683static int __init init_rpcsec_gss(void)
1684{
1685 int err = 0;
1686
1687 err = rpcauth_register(&authgss_ops);
1688 if (err)
1689 goto out;
1690 err = gss_svc_init();
1691 if (err)
1692 goto out_unregister;
1693 err = register_pernet_subsys(&rpcsec_gss_net_ops);
1694 if (err)
1695 goto out_svc_exit;
1696 rpc_init_wait_queue(&pipe_version_rpc_waitqueue, "gss pipe version");
1697 return 0;
1698out_svc_exit:
1699 gss_svc_shutdown();
1700out_unregister:
1701 rpcauth_unregister(&authgss_ops);
1702out:
1703 return err;
1704}
1705
1706static void __exit exit_rpcsec_gss(void)
1707{
1708 unregister_pernet_subsys(&rpcsec_gss_net_ops);
1709 gss_svc_shutdown();
1710 rpcauth_unregister(&authgss_ops);
1711 rcu_barrier(); /* Wait for completion of call_rcu()'s */
1712}
1713
1714MODULE_LICENSE("GPL");
1715module_param_named(expired_cred_retry_delay,
1716 gss_expired_cred_retry_delay,
1717 uint, 0644);
1718MODULE_PARM_DESC(expired_cred_retry_delay, "Timeout (in seconds) until "
1719 "the RPC engine retries an expired credential");
1720
1721module_init(init_rpcsec_gss)
1722module_exit(exit_rpcsec_gss)