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1// SPDX-License-Identifier: GPL-2.0-or-later
2/* RxRPC key management
3 *
4 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 *
7 * RxRPC keys should have a description of describing their purpose:
8 * "afs@example.com"
9 */
10
11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12
13#include <crypto/skcipher.h>
14#include <linux/module.h>
15#include <linux/net.h>
16#include <linux/skbuff.h>
17#include <linux/key-type.h>
18#include <linux/ctype.h>
19#include <linux/slab.h>
20#include <net/sock.h>
21#include <net/af_rxrpc.h>
22#include <keys/rxrpc-type.h>
23#include <keys/user-type.h>
24#include "ar-internal.h"
25
26static int rxrpc_preparse(struct key_preparsed_payload *);
27static void rxrpc_free_preparse(struct key_preparsed_payload *);
28static void rxrpc_destroy(struct key *);
29static void rxrpc_describe(const struct key *, struct seq_file *);
30static long rxrpc_read(const struct key *, char *, size_t);
31
32/*
33 * rxrpc defined keys take an arbitrary string as the description and an
34 * arbitrary blob of data as the payload
35 */
36struct key_type key_type_rxrpc = {
37 .name = "rxrpc",
38 .flags = KEY_TYPE_NET_DOMAIN,
39 .preparse = rxrpc_preparse,
40 .free_preparse = rxrpc_free_preparse,
41 .instantiate = generic_key_instantiate,
42 .destroy = rxrpc_destroy,
43 .describe = rxrpc_describe,
44 .read = rxrpc_read,
45};
46EXPORT_SYMBOL(key_type_rxrpc);
47
48/*
49 * parse an RxKAD type XDR format token
50 * - the caller guarantees we have at least 4 words
51 */
52static int rxrpc_preparse_xdr_rxkad(struct key_preparsed_payload *prep,
53 size_t datalen,
54 const __be32 *xdr, unsigned int toklen)
55{
56 struct rxrpc_key_token *token, **pptoken;
57 time64_t expiry;
58 size_t plen;
59 u32 tktlen;
60
61 _enter(",{%x,%x,%x,%x},%u",
62 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
63 toklen);
64
65 if (toklen <= 8 * 4)
66 return -EKEYREJECTED;
67 tktlen = ntohl(xdr[7]);
68 _debug("tktlen: %x", tktlen);
69 if (tktlen > AFSTOKEN_RK_TIX_MAX)
70 return -EKEYREJECTED;
71 if (toklen < 8 * 4 + tktlen)
72 return -EKEYREJECTED;
73
74 plen = sizeof(*token) + sizeof(*token->kad) + tktlen;
75 prep->quotalen = datalen + plen;
76
77 plen -= sizeof(*token);
78 token = kzalloc(sizeof(*token), GFP_KERNEL);
79 if (!token)
80 return -ENOMEM;
81
82 token->kad = kzalloc(plen, GFP_KERNEL);
83 if (!token->kad) {
84 kfree(token);
85 return -ENOMEM;
86 }
87
88 token->security_index = RXRPC_SECURITY_RXKAD;
89 token->kad->ticket_len = tktlen;
90 token->kad->vice_id = ntohl(xdr[0]);
91 token->kad->kvno = ntohl(xdr[1]);
92 token->kad->start = ntohl(xdr[4]);
93 token->kad->expiry = ntohl(xdr[5]);
94 token->kad->primary_flag = ntohl(xdr[6]);
95 memcpy(&token->kad->session_key, &xdr[2], 8);
96 memcpy(&token->kad->ticket, &xdr[8], tktlen);
97
98 _debug("SCIX: %u", token->security_index);
99 _debug("TLEN: %u", token->kad->ticket_len);
100 _debug("EXPY: %x", token->kad->expiry);
101 _debug("KVNO: %u", token->kad->kvno);
102 _debug("PRIM: %u", token->kad->primary_flag);
103 _debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
104 token->kad->session_key[0], token->kad->session_key[1],
105 token->kad->session_key[2], token->kad->session_key[3],
106 token->kad->session_key[4], token->kad->session_key[5],
107 token->kad->session_key[6], token->kad->session_key[7]);
108 if (token->kad->ticket_len >= 8)
109 _debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
110 token->kad->ticket[0], token->kad->ticket[1],
111 token->kad->ticket[2], token->kad->ticket[3],
112 token->kad->ticket[4], token->kad->ticket[5],
113 token->kad->ticket[6], token->kad->ticket[7]);
114
115 /* count the number of tokens attached */
116 prep->payload.data[1] = (void *)((unsigned long)prep->payload.data[1] + 1);
117
118 /* attach the data */
119 for (pptoken = (struct rxrpc_key_token **)&prep->payload.data[0];
120 *pptoken;
121 pptoken = &(*pptoken)->next)
122 continue;
123 *pptoken = token;
124 expiry = rxrpc_u32_to_time64(token->kad->expiry);
125 if (expiry < prep->expiry)
126 prep->expiry = expiry;
127
128 _leave(" = 0");
129 return 0;
130}
131
132/*
133 * attempt to parse the data as the XDR format
134 * - the caller guarantees we have more than 7 words
135 */
136static int rxrpc_preparse_xdr(struct key_preparsed_payload *prep)
137{
138 const __be32 *xdr = prep->data, *token, *p;
139 const char *cp;
140 unsigned int len, paddedlen, loop, ntoken, toklen, sec_ix;
141 size_t datalen = prep->datalen;
142 int ret, ret2;
143
144 _enter(",{%x,%x,%x,%x},%zu",
145 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
146 prep->datalen);
147
148 if (datalen > AFSTOKEN_LENGTH_MAX)
149 goto not_xdr;
150
151 /* XDR is an array of __be32's */
152 if (datalen & 3)
153 goto not_xdr;
154
155 /* the flags should be 0 (the setpag bit must be handled by
156 * userspace) */
157 if (ntohl(*xdr++) != 0)
158 goto not_xdr;
159 datalen -= 4;
160
161 /* check the cell name */
162 len = ntohl(*xdr++);
163 if (len < 1 || len > AFSTOKEN_CELL_MAX)
164 goto not_xdr;
165 datalen -= 4;
166 paddedlen = (len + 3) & ~3;
167 if (paddedlen > datalen)
168 goto not_xdr;
169
170 cp = (const char *) xdr;
171 for (loop = 0; loop < len; loop++)
172 if (!isprint(cp[loop]))
173 goto not_xdr;
174 for (; loop < paddedlen; loop++)
175 if (cp[loop])
176 goto not_xdr;
177 _debug("cellname: [%u/%u] '%*.*s'",
178 len, paddedlen, len, len, (const char *) xdr);
179 datalen -= paddedlen;
180 xdr += paddedlen >> 2;
181
182 /* get the token count */
183 if (datalen < 12)
184 goto not_xdr;
185 ntoken = ntohl(*xdr++);
186 datalen -= 4;
187 _debug("ntoken: %x", ntoken);
188 if (ntoken < 1 || ntoken > AFSTOKEN_MAX)
189 goto not_xdr;
190
191 /* check each token wrapper */
192 p = xdr;
193 loop = ntoken;
194 do {
195 if (datalen < 8)
196 goto not_xdr;
197 toklen = ntohl(*p++);
198 sec_ix = ntohl(*p);
199 datalen -= 4;
200 _debug("token: [%x/%zx] %x", toklen, datalen, sec_ix);
201 paddedlen = (toklen + 3) & ~3;
202 if (toklen < 20 || toklen > datalen || paddedlen > datalen)
203 goto not_xdr;
204 datalen -= paddedlen;
205 p += paddedlen >> 2;
206
207 } while (--loop > 0);
208
209 _debug("remainder: %zu", datalen);
210 if (datalen != 0)
211 goto not_xdr;
212
213 /* okay: we're going to assume it's valid XDR format
214 * - we ignore the cellname, relying on the key to be correctly named
215 */
216 ret = -EPROTONOSUPPORT;
217 do {
218 toklen = ntohl(*xdr++);
219 token = xdr;
220 xdr += (toklen + 3) / 4;
221
222 sec_ix = ntohl(*token++);
223 toklen -= 4;
224
225 _debug("TOKEN type=%x len=%x", sec_ix, toklen);
226
227 switch (sec_ix) {
228 case RXRPC_SECURITY_RXKAD:
229 ret2 = rxrpc_preparse_xdr_rxkad(prep, datalen, token, toklen);
230 break;
231 default:
232 ret2 = -EPROTONOSUPPORT;
233 break;
234 }
235
236 switch (ret2) {
237 case 0:
238 ret = 0;
239 break;
240 case -EPROTONOSUPPORT:
241 break;
242 case -ENOPKG:
243 if (ret != 0)
244 ret = -ENOPKG;
245 break;
246 default:
247 ret = ret2;
248 goto error;
249 }
250
251 } while (--ntoken > 0);
252
253error:
254 _leave(" = %d", ret);
255 return ret;
256
257not_xdr:
258 _leave(" = -EPROTO");
259 return -EPROTO;
260}
261
262/*
263 * Preparse an rxrpc defined key.
264 *
265 * Data should be of the form:
266 * OFFSET LEN CONTENT
267 * 0 4 key interface version number
268 * 4 2 security index (type)
269 * 6 2 ticket length
270 * 8 4 key expiry time (time_t)
271 * 12 4 kvno
272 * 16 8 session key
273 * 24 [len] ticket
274 *
275 * if no data is provided, then a no-security key is made
276 */
277static int rxrpc_preparse(struct key_preparsed_payload *prep)
278{
279 const struct rxrpc_key_data_v1 *v1;
280 struct rxrpc_key_token *token, **pp;
281 time64_t expiry;
282 size_t plen;
283 u32 kver;
284 int ret;
285
286 _enter("%zu", prep->datalen);
287
288 /* handle a no-security key */
289 if (!prep->data && prep->datalen == 0)
290 return 0;
291
292 /* determine if the XDR payload format is being used */
293 if (prep->datalen > 7 * 4) {
294 ret = rxrpc_preparse_xdr(prep);
295 if (ret != -EPROTO)
296 return ret;
297 }
298
299 /* get the key interface version number */
300 ret = -EINVAL;
301 if (prep->datalen <= 4 || !prep->data)
302 goto error;
303 memcpy(&kver, prep->data, sizeof(kver));
304 prep->data += sizeof(kver);
305 prep->datalen -= sizeof(kver);
306
307 _debug("KEY I/F VERSION: %u", kver);
308
309 ret = -EKEYREJECTED;
310 if (kver != 1)
311 goto error;
312
313 /* deal with a version 1 key */
314 ret = -EINVAL;
315 if (prep->datalen < sizeof(*v1))
316 goto error;
317
318 v1 = prep->data;
319 if (prep->datalen != sizeof(*v1) + v1->ticket_length)
320 goto error;
321
322 _debug("SCIX: %u", v1->security_index);
323 _debug("TLEN: %u", v1->ticket_length);
324 _debug("EXPY: %x", v1->expiry);
325 _debug("KVNO: %u", v1->kvno);
326 _debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
327 v1->session_key[0], v1->session_key[1],
328 v1->session_key[2], v1->session_key[3],
329 v1->session_key[4], v1->session_key[5],
330 v1->session_key[6], v1->session_key[7]);
331 if (v1->ticket_length >= 8)
332 _debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
333 v1->ticket[0], v1->ticket[1],
334 v1->ticket[2], v1->ticket[3],
335 v1->ticket[4], v1->ticket[5],
336 v1->ticket[6], v1->ticket[7]);
337
338 ret = -EPROTONOSUPPORT;
339 if (v1->security_index != RXRPC_SECURITY_RXKAD)
340 goto error;
341
342 plen = sizeof(*token->kad) + v1->ticket_length;
343 prep->quotalen = plen + sizeof(*token);
344
345 ret = -ENOMEM;
346 token = kzalloc(sizeof(*token), GFP_KERNEL);
347 if (!token)
348 goto error;
349 token->kad = kzalloc(plen, GFP_KERNEL);
350 if (!token->kad)
351 goto error_free;
352
353 token->security_index = RXRPC_SECURITY_RXKAD;
354 token->kad->ticket_len = v1->ticket_length;
355 token->kad->expiry = v1->expiry;
356 token->kad->kvno = v1->kvno;
357 memcpy(&token->kad->session_key, &v1->session_key, 8);
358 memcpy(&token->kad->ticket, v1->ticket, v1->ticket_length);
359
360 /* count the number of tokens attached */
361 prep->payload.data[1] = (void *)((unsigned long)prep->payload.data[1] + 1);
362
363 /* attach the data */
364 pp = (struct rxrpc_key_token **)&prep->payload.data[0];
365 while (*pp)
366 pp = &(*pp)->next;
367 *pp = token;
368 expiry = rxrpc_u32_to_time64(token->kad->expiry);
369 if (expiry < prep->expiry)
370 prep->expiry = expiry;
371 token = NULL;
372 ret = 0;
373
374error_free:
375 kfree(token);
376error:
377 return ret;
378}
379
380/*
381 * Free token list.
382 */
383static void rxrpc_free_token_list(struct rxrpc_key_token *token)
384{
385 struct rxrpc_key_token *next;
386
387 for (; token; token = next) {
388 next = token->next;
389 switch (token->security_index) {
390 case RXRPC_SECURITY_RXKAD:
391 kfree(token->kad);
392 break;
393 default:
394 pr_err("Unknown token type %x on rxrpc key\n",
395 token->security_index);
396 BUG();
397 }
398
399 kfree(token);
400 }
401}
402
403/*
404 * Clean up preparse data.
405 */
406static void rxrpc_free_preparse(struct key_preparsed_payload *prep)
407{
408 rxrpc_free_token_list(prep->payload.data[0]);
409}
410
411/*
412 * dispose of the data dangling from the corpse of a rxrpc key
413 */
414static void rxrpc_destroy(struct key *key)
415{
416 rxrpc_free_token_list(key->payload.data[0]);
417}
418
419/*
420 * describe the rxrpc key
421 */
422static void rxrpc_describe(const struct key *key, struct seq_file *m)
423{
424 const struct rxrpc_key_token *token;
425 const char *sep = ": ";
426
427 seq_puts(m, key->description);
428
429 for (token = key->payload.data[0]; token; token = token->next) {
430 seq_puts(m, sep);
431
432 switch (token->security_index) {
433 case RXRPC_SECURITY_RXKAD:
434 seq_puts(m, "ka");
435 break;
436 default: /* we have a ticket we can't encode */
437 seq_printf(m, "%u", token->security_index);
438 break;
439 }
440
441 sep = " ";
442 }
443}
444
445/*
446 * grab the security key for a socket
447 */
448int rxrpc_request_key(struct rxrpc_sock *rx, sockptr_t optval, int optlen)
449{
450 struct key *key;
451 char *description;
452
453 _enter("");
454
455 if (optlen <= 0 || optlen > PAGE_SIZE - 1 || rx->securities)
456 return -EINVAL;
457
458 description = memdup_sockptr_nul(optval, optlen);
459 if (IS_ERR(description))
460 return PTR_ERR(description);
461
462 key = request_key_net(&key_type_rxrpc, description, sock_net(&rx->sk), NULL);
463 if (IS_ERR(key)) {
464 kfree(description);
465 _leave(" = %ld", PTR_ERR(key));
466 return PTR_ERR(key);
467 }
468
469 rx->key = key;
470 kfree(description);
471 _leave(" = 0 [key %x]", key->serial);
472 return 0;
473}
474
475/*
476 * generate a server data key
477 */
478int rxrpc_get_server_data_key(struct rxrpc_connection *conn,
479 const void *session_key,
480 time64_t expiry,
481 u32 kvno)
482{
483 const struct cred *cred = current_cred();
484 struct key *key;
485 int ret;
486
487 struct {
488 u32 kver;
489 struct rxrpc_key_data_v1 v1;
490 } data;
491
492 _enter("");
493
494 key = key_alloc(&key_type_rxrpc, "x",
495 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, 0,
496 KEY_ALLOC_NOT_IN_QUOTA, NULL);
497 if (IS_ERR(key)) {
498 _leave(" = -ENOMEM [alloc %ld]", PTR_ERR(key));
499 return -ENOMEM;
500 }
501
502 _debug("key %d", key_serial(key));
503
504 data.kver = 1;
505 data.v1.security_index = RXRPC_SECURITY_RXKAD;
506 data.v1.ticket_length = 0;
507 data.v1.expiry = rxrpc_time64_to_u32(expiry);
508 data.v1.kvno = 0;
509
510 memcpy(&data.v1.session_key, session_key, sizeof(data.v1.session_key));
511
512 ret = key_instantiate_and_link(key, &data, sizeof(data), NULL, NULL);
513 if (ret < 0)
514 goto error;
515
516 conn->key = key;
517 _leave(" = 0 [%d]", key_serial(key));
518 return 0;
519
520error:
521 key_revoke(key);
522 key_put(key);
523 _leave(" = -ENOMEM [ins %d]", ret);
524 return -ENOMEM;
525}
526EXPORT_SYMBOL(rxrpc_get_server_data_key);
527
528/**
529 * rxrpc_get_null_key - Generate a null RxRPC key
530 * @keyname: The name to give the key.
531 *
532 * Generate a null RxRPC key that can be used to indicate anonymous security is
533 * required for a particular domain.
534 */
535struct key *rxrpc_get_null_key(const char *keyname)
536{
537 const struct cred *cred = current_cred();
538 struct key *key;
539 int ret;
540
541 key = key_alloc(&key_type_rxrpc, keyname,
542 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
543 KEY_POS_SEARCH, KEY_ALLOC_NOT_IN_QUOTA, NULL);
544 if (IS_ERR(key))
545 return key;
546
547 ret = key_instantiate_and_link(key, NULL, 0, NULL, NULL);
548 if (ret < 0) {
549 key_revoke(key);
550 key_put(key);
551 return ERR_PTR(ret);
552 }
553
554 return key;
555}
556EXPORT_SYMBOL(rxrpc_get_null_key);
557
558/*
559 * read the contents of an rxrpc key
560 * - this returns the result in XDR form
561 */
562static long rxrpc_read(const struct key *key,
563 char *buffer, size_t buflen)
564{
565 const struct rxrpc_key_token *token;
566 size_t size;
567 __be32 *xdr, *oldxdr;
568 u32 cnlen, toksize, ntoks, tok, zero;
569 u16 toksizes[AFSTOKEN_MAX];
570
571 _enter("");
572
573 /* we don't know what form we should return non-AFS keys in */
574 if (memcmp(key->description, "afs@", 4) != 0)
575 return -EOPNOTSUPP;
576 cnlen = strlen(key->description + 4);
577
578#define RND(X) (((X) + 3) & ~3)
579
580 /* AFS keys we return in XDR form, so we need to work out the size of
581 * the XDR */
582 size = 2 * 4; /* flags, cellname len */
583 size += RND(cnlen); /* cellname */
584 size += 1 * 4; /* token count */
585
586 ntoks = 0;
587 for (token = key->payload.data[0]; token; token = token->next) {
588 toksize = 4; /* sec index */
589
590 switch (token->security_index) {
591 case RXRPC_SECURITY_RXKAD:
592 toksize += 8 * 4; /* viceid, kvno, key*2, begin,
593 * end, primary, tktlen */
594 if (!token->no_leak_key)
595 toksize += RND(token->kad->ticket_len);
596 break;
597
598 default: /* we have a ticket we can't encode */
599 pr_err("Unsupported key token type (%u)\n",
600 token->security_index);
601 return -ENOPKG;
602 }
603
604 _debug("token[%u]: toksize=%u", ntoks, toksize);
605 if (WARN_ON(toksize > AFSTOKEN_LENGTH_MAX))
606 return -EIO;
607
608 toksizes[ntoks++] = toksize;
609 size += toksize + 4; /* each token has a length word */
610 }
611
612#undef RND
613
614 if (!buffer || buflen < size)
615 return size;
616
617 xdr = (__be32 *)buffer;
618 zero = 0;
619#define ENCODE(x) \
620 do { \
621 *xdr++ = htonl(x); \
622 } while(0)
623#define ENCODE_DATA(l, s) \
624 do { \
625 u32 _l = (l); \
626 ENCODE(l); \
627 memcpy(xdr, (s), _l); \
628 if (_l & 3) \
629 memcpy((u8 *)xdr + _l, &zero, 4 - (_l & 3)); \
630 xdr += (_l + 3) >> 2; \
631 } while(0)
632#define ENCODE_BYTES(l, s) \
633 do { \
634 u32 _l = (l); \
635 memcpy(xdr, (s), _l); \
636 if (_l & 3) \
637 memcpy((u8 *)xdr + _l, &zero, 4 - (_l & 3)); \
638 xdr += (_l + 3) >> 2; \
639 } while(0)
640#define ENCODE64(x) \
641 do { \
642 __be64 y = cpu_to_be64(x); \
643 memcpy(xdr, &y, 8); \
644 xdr += 8 >> 2; \
645 } while(0)
646#define ENCODE_STR(s) \
647 do { \
648 const char *_s = (s); \
649 ENCODE_DATA(strlen(_s), _s); \
650 } while(0)
651
652 ENCODE(0); /* flags */
653 ENCODE_DATA(cnlen, key->description + 4); /* cellname */
654 ENCODE(ntoks);
655
656 tok = 0;
657 for (token = key->payload.data[0]; token; token = token->next) {
658 toksize = toksizes[tok++];
659 ENCODE(toksize);
660 oldxdr = xdr;
661 ENCODE(token->security_index);
662
663 switch (token->security_index) {
664 case RXRPC_SECURITY_RXKAD:
665 ENCODE(token->kad->vice_id);
666 ENCODE(token->kad->kvno);
667 ENCODE_BYTES(8, token->kad->session_key);
668 ENCODE(token->kad->start);
669 ENCODE(token->kad->expiry);
670 ENCODE(token->kad->primary_flag);
671 if (token->no_leak_key)
672 ENCODE(0);
673 else
674 ENCODE_DATA(token->kad->ticket_len, token->kad->ticket);
675 break;
676
677 default:
678 pr_err("Unsupported key token type (%u)\n",
679 token->security_index);
680 return -ENOPKG;
681 }
682
683 if (WARN_ON((unsigned long)xdr - (unsigned long)oldxdr ==
684 toksize))
685 return -EIO;
686 }
687
688#undef ENCODE_STR
689#undef ENCODE_DATA
690#undef ENCODE64
691#undef ENCODE
692
693 if (WARN_ON(tok != ntoks))
694 return -EIO;
695 if (WARN_ON((unsigned long)xdr - (unsigned long)buffer != size))
696 return -EIO;
697 _leave(" = %zu", size);
698 return size;
699}
1/* RxRPC key management
2 *
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 *
11 * RxRPC keys should have a description of describing their purpose:
12 * "afs@CAMBRIDGE.REDHAT.COM>
13 */
14
15#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16
17#include <crypto/skcipher.h>
18#include <linux/module.h>
19#include <linux/net.h>
20#include <linux/skbuff.h>
21#include <linux/key-type.h>
22#include <linux/ctype.h>
23#include <linux/slab.h>
24#include <net/sock.h>
25#include <net/af_rxrpc.h>
26#include <keys/rxrpc-type.h>
27#include <keys/user-type.h>
28#include "ar-internal.h"
29
30static int rxrpc_vet_description_s(const char *);
31static int rxrpc_preparse(struct key_preparsed_payload *);
32static int rxrpc_preparse_s(struct key_preparsed_payload *);
33static void rxrpc_free_preparse(struct key_preparsed_payload *);
34static void rxrpc_free_preparse_s(struct key_preparsed_payload *);
35static void rxrpc_destroy(struct key *);
36static void rxrpc_destroy_s(struct key *);
37static void rxrpc_describe(const struct key *, struct seq_file *);
38static long rxrpc_read(const struct key *, char __user *, size_t);
39
40/*
41 * rxrpc defined keys take an arbitrary string as the description and an
42 * arbitrary blob of data as the payload
43 */
44struct key_type key_type_rxrpc = {
45 .name = "rxrpc",
46 .preparse = rxrpc_preparse,
47 .free_preparse = rxrpc_free_preparse,
48 .instantiate = generic_key_instantiate,
49 .destroy = rxrpc_destroy,
50 .describe = rxrpc_describe,
51 .read = rxrpc_read,
52};
53EXPORT_SYMBOL(key_type_rxrpc);
54
55/*
56 * rxrpc server defined keys take "<serviceId>:<securityIndex>" as the
57 * description and an 8-byte decryption key as the payload
58 */
59struct key_type key_type_rxrpc_s = {
60 .name = "rxrpc_s",
61 .vet_description = rxrpc_vet_description_s,
62 .preparse = rxrpc_preparse_s,
63 .free_preparse = rxrpc_free_preparse_s,
64 .instantiate = generic_key_instantiate,
65 .destroy = rxrpc_destroy_s,
66 .describe = rxrpc_describe,
67};
68
69/*
70 * Vet the description for an RxRPC server key
71 */
72static int rxrpc_vet_description_s(const char *desc)
73{
74 unsigned long num;
75 char *p;
76
77 num = simple_strtoul(desc, &p, 10);
78 if (*p != ':' || num > 65535)
79 return -EINVAL;
80 num = simple_strtoul(p + 1, &p, 10);
81 if (*p || num < 1 || num > 255)
82 return -EINVAL;
83 return 0;
84}
85
86/*
87 * parse an RxKAD type XDR format token
88 * - the caller guarantees we have at least 4 words
89 */
90static int rxrpc_preparse_xdr_rxkad(struct key_preparsed_payload *prep,
91 size_t datalen,
92 const __be32 *xdr, unsigned int toklen)
93{
94 struct rxrpc_key_token *token, **pptoken;
95 size_t plen;
96 u32 tktlen;
97
98 _enter(",{%x,%x,%x,%x},%u",
99 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
100 toklen);
101
102 if (toklen <= 8 * 4)
103 return -EKEYREJECTED;
104 tktlen = ntohl(xdr[7]);
105 _debug("tktlen: %x", tktlen);
106 if (tktlen > AFSTOKEN_RK_TIX_MAX)
107 return -EKEYREJECTED;
108 if (toklen < 8 * 4 + tktlen)
109 return -EKEYREJECTED;
110
111 plen = sizeof(*token) + sizeof(*token->kad) + tktlen;
112 prep->quotalen = datalen + plen;
113
114 plen -= sizeof(*token);
115 token = kzalloc(sizeof(*token), GFP_KERNEL);
116 if (!token)
117 return -ENOMEM;
118
119 token->kad = kzalloc(plen, GFP_KERNEL);
120 if (!token->kad) {
121 kfree(token);
122 return -ENOMEM;
123 }
124
125 token->security_index = RXRPC_SECURITY_RXKAD;
126 token->kad->ticket_len = tktlen;
127 token->kad->vice_id = ntohl(xdr[0]);
128 token->kad->kvno = ntohl(xdr[1]);
129 token->kad->start = ntohl(xdr[4]);
130 token->kad->expiry = ntohl(xdr[5]);
131 token->kad->primary_flag = ntohl(xdr[6]);
132 memcpy(&token->kad->session_key, &xdr[2], 8);
133 memcpy(&token->kad->ticket, &xdr[8], tktlen);
134
135 _debug("SCIX: %u", token->security_index);
136 _debug("TLEN: %u", token->kad->ticket_len);
137 _debug("EXPY: %x", token->kad->expiry);
138 _debug("KVNO: %u", token->kad->kvno);
139 _debug("PRIM: %u", token->kad->primary_flag);
140 _debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
141 token->kad->session_key[0], token->kad->session_key[1],
142 token->kad->session_key[2], token->kad->session_key[3],
143 token->kad->session_key[4], token->kad->session_key[5],
144 token->kad->session_key[6], token->kad->session_key[7]);
145 if (token->kad->ticket_len >= 8)
146 _debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
147 token->kad->ticket[0], token->kad->ticket[1],
148 token->kad->ticket[2], token->kad->ticket[3],
149 token->kad->ticket[4], token->kad->ticket[5],
150 token->kad->ticket[6], token->kad->ticket[7]);
151
152 /* count the number of tokens attached */
153 prep->payload.data[1] = (void *)((unsigned long)prep->payload.data[1] + 1);
154
155 /* attach the data */
156 for (pptoken = (struct rxrpc_key_token **)&prep->payload.data[0];
157 *pptoken;
158 pptoken = &(*pptoken)->next)
159 continue;
160 *pptoken = token;
161 if (token->kad->expiry < prep->expiry)
162 prep->expiry = token->kad->expiry;
163
164 _leave(" = 0");
165 return 0;
166}
167
168static void rxrpc_free_krb5_principal(struct krb5_principal *princ)
169{
170 int loop;
171
172 if (princ->name_parts) {
173 for (loop = princ->n_name_parts - 1; loop >= 0; loop--)
174 kfree(princ->name_parts[loop]);
175 kfree(princ->name_parts);
176 }
177 kfree(princ->realm);
178}
179
180static void rxrpc_free_krb5_tagged(struct krb5_tagged_data *td)
181{
182 kfree(td->data);
183}
184
185/*
186 * free up an RxK5 token
187 */
188static void rxrpc_rxk5_free(struct rxk5_key *rxk5)
189{
190 int loop;
191
192 rxrpc_free_krb5_principal(&rxk5->client);
193 rxrpc_free_krb5_principal(&rxk5->server);
194 rxrpc_free_krb5_tagged(&rxk5->session);
195
196 if (rxk5->addresses) {
197 for (loop = rxk5->n_addresses - 1; loop >= 0; loop--)
198 rxrpc_free_krb5_tagged(&rxk5->addresses[loop]);
199 kfree(rxk5->addresses);
200 }
201 if (rxk5->authdata) {
202 for (loop = rxk5->n_authdata - 1; loop >= 0; loop--)
203 rxrpc_free_krb5_tagged(&rxk5->authdata[loop]);
204 kfree(rxk5->authdata);
205 }
206
207 kfree(rxk5->ticket);
208 kfree(rxk5->ticket2);
209 kfree(rxk5);
210}
211
212/*
213 * extract a krb5 principal
214 */
215static int rxrpc_krb5_decode_principal(struct krb5_principal *princ,
216 const __be32 **_xdr,
217 unsigned int *_toklen)
218{
219 const __be32 *xdr = *_xdr;
220 unsigned int toklen = *_toklen, n_parts, loop, tmp;
221
222 /* there must be at least one name, and at least #names+1 length
223 * words */
224 if (toklen <= 12)
225 return -EINVAL;
226
227 _enter(",{%x,%x,%x},%u",
228 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), toklen);
229
230 n_parts = ntohl(*xdr++);
231 toklen -= 4;
232 if (n_parts <= 0 || n_parts > AFSTOKEN_K5_COMPONENTS_MAX)
233 return -EINVAL;
234 princ->n_name_parts = n_parts;
235
236 if (toklen <= (n_parts + 1) * 4)
237 return -EINVAL;
238
239 princ->name_parts = kcalloc(n_parts, sizeof(char *), GFP_KERNEL);
240 if (!princ->name_parts)
241 return -ENOMEM;
242
243 for (loop = 0; loop < n_parts; loop++) {
244 if (toklen < 4)
245 return -EINVAL;
246 tmp = ntohl(*xdr++);
247 toklen -= 4;
248 if (tmp <= 0 || tmp > AFSTOKEN_STRING_MAX)
249 return -EINVAL;
250 if (tmp > toklen)
251 return -EINVAL;
252 princ->name_parts[loop] = kmalloc(tmp + 1, GFP_KERNEL);
253 if (!princ->name_parts[loop])
254 return -ENOMEM;
255 memcpy(princ->name_parts[loop], xdr, tmp);
256 princ->name_parts[loop][tmp] = 0;
257 tmp = (tmp + 3) & ~3;
258 toklen -= tmp;
259 xdr += tmp >> 2;
260 }
261
262 if (toklen < 4)
263 return -EINVAL;
264 tmp = ntohl(*xdr++);
265 toklen -= 4;
266 if (tmp <= 0 || tmp > AFSTOKEN_K5_REALM_MAX)
267 return -EINVAL;
268 if (tmp > toklen)
269 return -EINVAL;
270 princ->realm = kmalloc(tmp + 1, GFP_KERNEL);
271 if (!princ->realm)
272 return -ENOMEM;
273 memcpy(princ->realm, xdr, tmp);
274 princ->realm[tmp] = 0;
275 tmp = (tmp + 3) & ~3;
276 toklen -= tmp;
277 xdr += tmp >> 2;
278
279 _debug("%s/...@%s", princ->name_parts[0], princ->realm);
280
281 *_xdr = xdr;
282 *_toklen = toklen;
283 _leave(" = 0 [toklen=%u]", toklen);
284 return 0;
285}
286
287/*
288 * extract a piece of krb5 tagged data
289 */
290static int rxrpc_krb5_decode_tagged_data(struct krb5_tagged_data *td,
291 size_t max_data_size,
292 const __be32 **_xdr,
293 unsigned int *_toklen)
294{
295 const __be32 *xdr = *_xdr;
296 unsigned int toklen = *_toklen, len;
297
298 /* there must be at least one tag and one length word */
299 if (toklen <= 8)
300 return -EINVAL;
301
302 _enter(",%zu,{%x,%x},%u",
303 max_data_size, ntohl(xdr[0]), ntohl(xdr[1]), toklen);
304
305 td->tag = ntohl(*xdr++);
306 len = ntohl(*xdr++);
307 toklen -= 8;
308 if (len > max_data_size)
309 return -EINVAL;
310 td->data_len = len;
311
312 if (len > 0) {
313 td->data = kmemdup(xdr, len, GFP_KERNEL);
314 if (!td->data)
315 return -ENOMEM;
316 len = (len + 3) & ~3;
317 toklen -= len;
318 xdr += len >> 2;
319 }
320
321 _debug("tag %x len %x", td->tag, td->data_len);
322
323 *_xdr = xdr;
324 *_toklen = toklen;
325 _leave(" = 0 [toklen=%u]", toklen);
326 return 0;
327}
328
329/*
330 * extract an array of tagged data
331 */
332static int rxrpc_krb5_decode_tagged_array(struct krb5_tagged_data **_td,
333 u8 *_n_elem,
334 u8 max_n_elem,
335 size_t max_elem_size,
336 const __be32 **_xdr,
337 unsigned int *_toklen)
338{
339 struct krb5_tagged_data *td;
340 const __be32 *xdr = *_xdr;
341 unsigned int toklen = *_toklen, n_elem, loop;
342 int ret;
343
344 /* there must be at least one count */
345 if (toklen < 4)
346 return -EINVAL;
347
348 _enter(",,%u,%zu,{%x},%u",
349 max_n_elem, max_elem_size, ntohl(xdr[0]), toklen);
350
351 n_elem = ntohl(*xdr++);
352 toklen -= 4;
353 if (n_elem > max_n_elem)
354 return -EINVAL;
355 *_n_elem = n_elem;
356 if (n_elem > 0) {
357 if (toklen <= (n_elem + 1) * 4)
358 return -EINVAL;
359
360 _debug("n_elem %d", n_elem);
361
362 td = kcalloc(n_elem, sizeof(struct krb5_tagged_data),
363 GFP_KERNEL);
364 if (!td)
365 return -ENOMEM;
366 *_td = td;
367
368 for (loop = 0; loop < n_elem; loop++) {
369 ret = rxrpc_krb5_decode_tagged_data(&td[loop],
370 max_elem_size,
371 &xdr, &toklen);
372 if (ret < 0)
373 return ret;
374 }
375 }
376
377 *_xdr = xdr;
378 *_toklen = toklen;
379 _leave(" = 0 [toklen=%u]", toklen);
380 return 0;
381}
382
383/*
384 * extract a krb5 ticket
385 */
386static int rxrpc_krb5_decode_ticket(u8 **_ticket, u16 *_tktlen,
387 const __be32 **_xdr, unsigned int *_toklen)
388{
389 const __be32 *xdr = *_xdr;
390 unsigned int toklen = *_toklen, len;
391
392 /* there must be at least one length word */
393 if (toklen <= 4)
394 return -EINVAL;
395
396 _enter(",{%x},%u", ntohl(xdr[0]), toklen);
397
398 len = ntohl(*xdr++);
399 toklen -= 4;
400 if (len > AFSTOKEN_K5_TIX_MAX)
401 return -EINVAL;
402 *_tktlen = len;
403
404 _debug("ticket len %u", len);
405
406 if (len > 0) {
407 *_ticket = kmemdup(xdr, len, GFP_KERNEL);
408 if (!*_ticket)
409 return -ENOMEM;
410 len = (len + 3) & ~3;
411 toklen -= len;
412 xdr += len >> 2;
413 }
414
415 *_xdr = xdr;
416 *_toklen = toklen;
417 _leave(" = 0 [toklen=%u]", toklen);
418 return 0;
419}
420
421/*
422 * parse an RxK5 type XDR format token
423 * - the caller guarantees we have at least 4 words
424 */
425static int rxrpc_preparse_xdr_rxk5(struct key_preparsed_payload *prep,
426 size_t datalen,
427 const __be32 *xdr, unsigned int toklen)
428{
429 struct rxrpc_key_token *token, **pptoken;
430 struct rxk5_key *rxk5;
431 const __be32 *end_xdr = xdr + (toklen >> 2);
432 int ret;
433
434 _enter(",{%x,%x,%x,%x},%u",
435 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
436 toklen);
437
438 /* reserve some payload space for this subkey - the length of the token
439 * is a reasonable approximation */
440 prep->quotalen = datalen + toklen;
441
442 token = kzalloc(sizeof(*token), GFP_KERNEL);
443 if (!token)
444 return -ENOMEM;
445
446 rxk5 = kzalloc(sizeof(*rxk5), GFP_KERNEL);
447 if (!rxk5) {
448 kfree(token);
449 return -ENOMEM;
450 }
451
452 token->security_index = RXRPC_SECURITY_RXK5;
453 token->k5 = rxk5;
454
455 /* extract the principals */
456 ret = rxrpc_krb5_decode_principal(&rxk5->client, &xdr, &toklen);
457 if (ret < 0)
458 goto error;
459 ret = rxrpc_krb5_decode_principal(&rxk5->server, &xdr, &toklen);
460 if (ret < 0)
461 goto error;
462
463 /* extract the session key and the encoding type (the tag field ->
464 * ENCTYPE_xxx) */
465 ret = rxrpc_krb5_decode_tagged_data(&rxk5->session, AFSTOKEN_DATA_MAX,
466 &xdr, &toklen);
467 if (ret < 0)
468 goto error;
469
470 if (toklen < 4 * 8 + 2 * 4)
471 goto inval;
472 rxk5->authtime = be64_to_cpup((const __be64 *) xdr);
473 xdr += 2;
474 rxk5->starttime = be64_to_cpup((const __be64 *) xdr);
475 xdr += 2;
476 rxk5->endtime = be64_to_cpup((const __be64 *) xdr);
477 xdr += 2;
478 rxk5->renew_till = be64_to_cpup((const __be64 *) xdr);
479 xdr += 2;
480 rxk5->is_skey = ntohl(*xdr++);
481 rxk5->flags = ntohl(*xdr++);
482 toklen -= 4 * 8 + 2 * 4;
483
484 _debug("times: a=%llx s=%llx e=%llx rt=%llx",
485 rxk5->authtime, rxk5->starttime, rxk5->endtime,
486 rxk5->renew_till);
487 _debug("is_skey=%x flags=%x", rxk5->is_skey, rxk5->flags);
488
489 /* extract the permitted client addresses */
490 ret = rxrpc_krb5_decode_tagged_array(&rxk5->addresses,
491 &rxk5->n_addresses,
492 AFSTOKEN_K5_ADDRESSES_MAX,
493 AFSTOKEN_DATA_MAX,
494 &xdr, &toklen);
495 if (ret < 0)
496 goto error;
497
498 ASSERTCMP((end_xdr - xdr) << 2, ==, toklen);
499
500 /* extract the tickets */
501 ret = rxrpc_krb5_decode_ticket(&rxk5->ticket, &rxk5->ticket_len,
502 &xdr, &toklen);
503 if (ret < 0)
504 goto error;
505 ret = rxrpc_krb5_decode_ticket(&rxk5->ticket2, &rxk5->ticket2_len,
506 &xdr, &toklen);
507 if (ret < 0)
508 goto error;
509
510 ASSERTCMP((end_xdr - xdr) << 2, ==, toklen);
511
512 /* extract the typed auth data */
513 ret = rxrpc_krb5_decode_tagged_array(&rxk5->authdata,
514 &rxk5->n_authdata,
515 AFSTOKEN_K5_AUTHDATA_MAX,
516 AFSTOKEN_BDATALN_MAX,
517 &xdr, &toklen);
518 if (ret < 0)
519 goto error;
520
521 ASSERTCMP((end_xdr - xdr) << 2, ==, toklen);
522
523 if (toklen != 0)
524 goto inval;
525
526 /* attach the payload */
527 for (pptoken = (struct rxrpc_key_token **)&prep->payload.data[0];
528 *pptoken;
529 pptoken = &(*pptoken)->next)
530 continue;
531 *pptoken = token;
532 if (token->kad->expiry < prep->expiry)
533 prep->expiry = token->kad->expiry;
534
535 _leave(" = 0");
536 return 0;
537
538inval:
539 ret = -EINVAL;
540error:
541 rxrpc_rxk5_free(rxk5);
542 kfree(token);
543 _leave(" = %d", ret);
544 return ret;
545}
546
547/*
548 * attempt to parse the data as the XDR format
549 * - the caller guarantees we have more than 7 words
550 */
551static int rxrpc_preparse_xdr(struct key_preparsed_payload *prep)
552{
553 const __be32 *xdr = prep->data, *token;
554 const char *cp;
555 unsigned int len, tmp, loop, ntoken, toklen, sec_ix;
556 size_t datalen = prep->datalen;
557 int ret;
558
559 _enter(",{%x,%x,%x,%x},%zu",
560 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
561 prep->datalen);
562
563 if (datalen > AFSTOKEN_LENGTH_MAX)
564 goto not_xdr;
565
566 /* XDR is an array of __be32's */
567 if (datalen & 3)
568 goto not_xdr;
569
570 /* the flags should be 0 (the setpag bit must be handled by
571 * userspace) */
572 if (ntohl(*xdr++) != 0)
573 goto not_xdr;
574 datalen -= 4;
575
576 /* check the cell name */
577 len = ntohl(*xdr++);
578 if (len < 1 || len > AFSTOKEN_CELL_MAX)
579 goto not_xdr;
580 datalen -= 4;
581 tmp = (len + 3) & ~3;
582 if (tmp > datalen)
583 goto not_xdr;
584
585 cp = (const char *) xdr;
586 for (loop = 0; loop < len; loop++)
587 if (!isprint(cp[loop]))
588 goto not_xdr;
589 if (len < tmp)
590 for (; loop < tmp; loop++)
591 if (cp[loop])
592 goto not_xdr;
593 _debug("cellname: [%u/%u] '%*.*s'",
594 len, tmp, len, len, (const char *) xdr);
595 datalen -= tmp;
596 xdr += tmp >> 2;
597
598 /* get the token count */
599 if (datalen < 12)
600 goto not_xdr;
601 ntoken = ntohl(*xdr++);
602 datalen -= 4;
603 _debug("ntoken: %x", ntoken);
604 if (ntoken < 1 || ntoken > AFSTOKEN_MAX)
605 goto not_xdr;
606
607 /* check each token wrapper */
608 token = xdr;
609 loop = ntoken;
610 do {
611 if (datalen < 8)
612 goto not_xdr;
613 toklen = ntohl(*xdr++);
614 sec_ix = ntohl(*xdr);
615 datalen -= 4;
616 _debug("token: [%x/%zx] %x", toklen, datalen, sec_ix);
617 if (toklen < 20 || toklen > datalen)
618 goto not_xdr;
619 datalen -= (toklen + 3) & ~3;
620 xdr += (toklen + 3) >> 2;
621
622 } while (--loop > 0);
623
624 _debug("remainder: %zu", datalen);
625 if (datalen != 0)
626 goto not_xdr;
627
628 /* okay: we're going to assume it's valid XDR format
629 * - we ignore the cellname, relying on the key to be correctly named
630 */
631 do {
632 xdr = token;
633 toklen = ntohl(*xdr++);
634 token = xdr + ((toklen + 3) >> 2);
635 sec_ix = ntohl(*xdr++);
636 toklen -= 4;
637
638 _debug("TOKEN type=%u [%p-%p]", sec_ix, xdr, token);
639
640 switch (sec_ix) {
641 case RXRPC_SECURITY_RXKAD:
642 ret = rxrpc_preparse_xdr_rxkad(prep, datalen, xdr, toklen);
643 if (ret != 0)
644 goto error;
645 break;
646
647 case RXRPC_SECURITY_RXK5:
648 ret = rxrpc_preparse_xdr_rxk5(prep, datalen, xdr, toklen);
649 if (ret != 0)
650 goto error;
651 break;
652
653 default:
654 ret = -EPROTONOSUPPORT;
655 goto error;
656 }
657
658 } while (--ntoken > 0);
659
660 _leave(" = 0");
661 return 0;
662
663not_xdr:
664 _leave(" = -EPROTO");
665 return -EPROTO;
666error:
667 _leave(" = %d", ret);
668 return ret;
669}
670
671/*
672 * Preparse an rxrpc defined key.
673 *
674 * Data should be of the form:
675 * OFFSET LEN CONTENT
676 * 0 4 key interface version number
677 * 4 2 security index (type)
678 * 6 2 ticket length
679 * 8 4 key expiry time (time_t)
680 * 12 4 kvno
681 * 16 8 session key
682 * 24 [len] ticket
683 *
684 * if no data is provided, then a no-security key is made
685 */
686static int rxrpc_preparse(struct key_preparsed_payload *prep)
687{
688 const struct rxrpc_key_data_v1 *v1;
689 struct rxrpc_key_token *token, **pp;
690 size_t plen;
691 u32 kver;
692 int ret;
693
694 _enter("%zu", prep->datalen);
695
696 /* handle a no-security key */
697 if (!prep->data && prep->datalen == 0)
698 return 0;
699
700 /* determine if the XDR payload format is being used */
701 if (prep->datalen > 7 * 4) {
702 ret = rxrpc_preparse_xdr(prep);
703 if (ret != -EPROTO)
704 return ret;
705 }
706
707 /* get the key interface version number */
708 ret = -EINVAL;
709 if (prep->datalen <= 4 || !prep->data)
710 goto error;
711 memcpy(&kver, prep->data, sizeof(kver));
712 prep->data += sizeof(kver);
713 prep->datalen -= sizeof(kver);
714
715 _debug("KEY I/F VERSION: %u", kver);
716
717 ret = -EKEYREJECTED;
718 if (kver != 1)
719 goto error;
720
721 /* deal with a version 1 key */
722 ret = -EINVAL;
723 if (prep->datalen < sizeof(*v1))
724 goto error;
725
726 v1 = prep->data;
727 if (prep->datalen != sizeof(*v1) + v1->ticket_length)
728 goto error;
729
730 _debug("SCIX: %u", v1->security_index);
731 _debug("TLEN: %u", v1->ticket_length);
732 _debug("EXPY: %x", v1->expiry);
733 _debug("KVNO: %u", v1->kvno);
734 _debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
735 v1->session_key[0], v1->session_key[1],
736 v1->session_key[2], v1->session_key[3],
737 v1->session_key[4], v1->session_key[5],
738 v1->session_key[6], v1->session_key[7]);
739 if (v1->ticket_length >= 8)
740 _debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
741 v1->ticket[0], v1->ticket[1],
742 v1->ticket[2], v1->ticket[3],
743 v1->ticket[4], v1->ticket[5],
744 v1->ticket[6], v1->ticket[7]);
745
746 ret = -EPROTONOSUPPORT;
747 if (v1->security_index != RXRPC_SECURITY_RXKAD)
748 goto error;
749
750 plen = sizeof(*token->kad) + v1->ticket_length;
751 prep->quotalen = plen + sizeof(*token);
752
753 ret = -ENOMEM;
754 token = kzalloc(sizeof(*token), GFP_KERNEL);
755 if (!token)
756 goto error;
757 token->kad = kzalloc(plen, GFP_KERNEL);
758 if (!token->kad)
759 goto error_free;
760
761 token->security_index = RXRPC_SECURITY_RXKAD;
762 token->kad->ticket_len = v1->ticket_length;
763 token->kad->expiry = v1->expiry;
764 token->kad->kvno = v1->kvno;
765 memcpy(&token->kad->session_key, &v1->session_key, 8);
766 memcpy(&token->kad->ticket, v1->ticket, v1->ticket_length);
767
768 /* count the number of tokens attached */
769 prep->payload.data[1] = (void *)((unsigned long)prep->payload.data[1] + 1);
770
771 /* attach the data */
772 pp = (struct rxrpc_key_token **)&prep->payload.data[0];
773 while (*pp)
774 pp = &(*pp)->next;
775 *pp = token;
776 if (token->kad->expiry < prep->expiry)
777 prep->expiry = token->kad->expiry;
778 token = NULL;
779 ret = 0;
780
781error_free:
782 kfree(token);
783error:
784 return ret;
785}
786
787/*
788 * Free token list.
789 */
790static void rxrpc_free_token_list(struct rxrpc_key_token *token)
791{
792 struct rxrpc_key_token *next;
793
794 for (; token; token = next) {
795 next = token->next;
796 switch (token->security_index) {
797 case RXRPC_SECURITY_RXKAD:
798 kfree(token->kad);
799 break;
800 case RXRPC_SECURITY_RXK5:
801 if (token->k5)
802 rxrpc_rxk5_free(token->k5);
803 break;
804 default:
805 pr_err("Unknown token type %x on rxrpc key\n",
806 token->security_index);
807 BUG();
808 }
809
810 kfree(token);
811 }
812}
813
814/*
815 * Clean up preparse data.
816 */
817static void rxrpc_free_preparse(struct key_preparsed_payload *prep)
818{
819 rxrpc_free_token_list(prep->payload.data[0]);
820}
821
822/*
823 * Preparse a server secret key.
824 *
825 * The data should be the 8-byte secret key.
826 */
827static int rxrpc_preparse_s(struct key_preparsed_payload *prep)
828{
829 struct crypto_skcipher *ci;
830
831 _enter("%zu", prep->datalen);
832
833 if (prep->datalen != 8)
834 return -EINVAL;
835
836 memcpy(&prep->payload.data[2], prep->data, 8);
837
838 ci = crypto_alloc_skcipher("pcbc(des)", 0, CRYPTO_ALG_ASYNC);
839 if (IS_ERR(ci)) {
840 _leave(" = %ld", PTR_ERR(ci));
841 return PTR_ERR(ci);
842 }
843
844 if (crypto_skcipher_setkey(ci, prep->data, 8) < 0)
845 BUG();
846
847 prep->payload.data[0] = ci;
848 _leave(" = 0");
849 return 0;
850}
851
852/*
853 * Clean up preparse data.
854 */
855static void rxrpc_free_preparse_s(struct key_preparsed_payload *prep)
856{
857 if (prep->payload.data[0])
858 crypto_free_skcipher(prep->payload.data[0]);
859}
860
861/*
862 * dispose of the data dangling from the corpse of a rxrpc key
863 */
864static void rxrpc_destroy(struct key *key)
865{
866 rxrpc_free_token_list(key->payload.data[0]);
867}
868
869/*
870 * dispose of the data dangling from the corpse of a rxrpc key
871 */
872static void rxrpc_destroy_s(struct key *key)
873{
874 if (key->payload.data[0]) {
875 crypto_free_skcipher(key->payload.data[0]);
876 key->payload.data[0] = NULL;
877 }
878}
879
880/*
881 * describe the rxrpc key
882 */
883static void rxrpc_describe(const struct key *key, struct seq_file *m)
884{
885 seq_puts(m, key->description);
886}
887
888/*
889 * grab the security key for a socket
890 */
891int rxrpc_request_key(struct rxrpc_sock *rx, char __user *optval, int optlen)
892{
893 struct key *key;
894 char *description;
895
896 _enter("");
897
898 if (optlen <= 0 || optlen > PAGE_SIZE - 1)
899 return -EINVAL;
900
901 description = memdup_user_nul(optval, optlen);
902 if (IS_ERR(description))
903 return PTR_ERR(description);
904
905 key = request_key(&key_type_rxrpc, description, NULL);
906 if (IS_ERR(key)) {
907 kfree(description);
908 _leave(" = %ld", PTR_ERR(key));
909 return PTR_ERR(key);
910 }
911
912 rx->key = key;
913 kfree(description);
914 _leave(" = 0 [key %x]", key->serial);
915 return 0;
916}
917
918/*
919 * grab the security keyring for a server socket
920 */
921int rxrpc_server_keyring(struct rxrpc_sock *rx, char __user *optval,
922 int optlen)
923{
924 struct key *key;
925 char *description;
926
927 _enter("");
928
929 if (optlen <= 0 || optlen > PAGE_SIZE - 1)
930 return -EINVAL;
931
932 description = memdup_user_nul(optval, optlen);
933 if (IS_ERR(description))
934 return PTR_ERR(description);
935
936 key = request_key(&key_type_keyring, description, NULL);
937 if (IS_ERR(key)) {
938 kfree(description);
939 _leave(" = %ld", PTR_ERR(key));
940 return PTR_ERR(key);
941 }
942
943 rx->securities = key;
944 kfree(description);
945 _leave(" = 0 [key %x]", key->serial);
946 return 0;
947}
948
949/*
950 * generate a server data key
951 */
952int rxrpc_get_server_data_key(struct rxrpc_connection *conn,
953 const void *session_key,
954 time_t expiry,
955 u32 kvno)
956{
957 const struct cred *cred = current_cred();
958 struct key *key;
959 int ret;
960
961 struct {
962 u32 kver;
963 struct rxrpc_key_data_v1 v1;
964 } data;
965
966 _enter("");
967
968 key = key_alloc(&key_type_rxrpc, "x",
969 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, 0,
970 KEY_ALLOC_NOT_IN_QUOTA, NULL);
971 if (IS_ERR(key)) {
972 _leave(" = -ENOMEM [alloc %ld]", PTR_ERR(key));
973 return -ENOMEM;
974 }
975
976 _debug("key %d", key_serial(key));
977
978 data.kver = 1;
979 data.v1.security_index = RXRPC_SECURITY_RXKAD;
980 data.v1.ticket_length = 0;
981 data.v1.expiry = expiry;
982 data.v1.kvno = 0;
983
984 memcpy(&data.v1.session_key, session_key, sizeof(data.v1.session_key));
985
986 ret = key_instantiate_and_link(key, &data, sizeof(data), NULL, NULL);
987 if (ret < 0)
988 goto error;
989
990 conn->params.key = key;
991 _leave(" = 0 [%d]", key_serial(key));
992 return 0;
993
994error:
995 key_revoke(key);
996 key_put(key);
997 _leave(" = -ENOMEM [ins %d]", ret);
998 return -ENOMEM;
999}
1000EXPORT_SYMBOL(rxrpc_get_server_data_key);
1001
1002/**
1003 * rxrpc_get_null_key - Generate a null RxRPC key
1004 * @keyname: The name to give the key.
1005 *
1006 * Generate a null RxRPC key that can be used to indicate anonymous security is
1007 * required for a particular domain.
1008 */
1009struct key *rxrpc_get_null_key(const char *keyname)
1010{
1011 const struct cred *cred = current_cred();
1012 struct key *key;
1013 int ret;
1014
1015 key = key_alloc(&key_type_rxrpc, keyname,
1016 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
1017 KEY_POS_SEARCH, KEY_ALLOC_NOT_IN_QUOTA, NULL);
1018 if (IS_ERR(key))
1019 return key;
1020
1021 ret = key_instantiate_and_link(key, NULL, 0, NULL, NULL);
1022 if (ret < 0) {
1023 key_revoke(key);
1024 key_put(key);
1025 return ERR_PTR(ret);
1026 }
1027
1028 return key;
1029}
1030EXPORT_SYMBOL(rxrpc_get_null_key);
1031
1032/*
1033 * read the contents of an rxrpc key
1034 * - this returns the result in XDR form
1035 */
1036static long rxrpc_read(const struct key *key,
1037 char __user *buffer, size_t buflen)
1038{
1039 const struct rxrpc_key_token *token;
1040 const struct krb5_principal *princ;
1041 size_t size;
1042 __be32 __user *xdr, *oldxdr;
1043 u32 cnlen, toksize, ntoks, tok, zero;
1044 u16 toksizes[AFSTOKEN_MAX];
1045 int loop;
1046
1047 _enter("");
1048
1049 /* we don't know what form we should return non-AFS keys in */
1050 if (memcmp(key->description, "afs@", 4) != 0)
1051 return -EOPNOTSUPP;
1052 cnlen = strlen(key->description + 4);
1053
1054#define RND(X) (((X) + 3) & ~3)
1055
1056 /* AFS keys we return in XDR form, so we need to work out the size of
1057 * the XDR */
1058 size = 2 * 4; /* flags, cellname len */
1059 size += RND(cnlen); /* cellname */
1060 size += 1 * 4; /* token count */
1061
1062 ntoks = 0;
1063 for (token = key->payload.data[0]; token; token = token->next) {
1064 toksize = 4; /* sec index */
1065
1066 switch (token->security_index) {
1067 case RXRPC_SECURITY_RXKAD:
1068 toksize += 8 * 4; /* viceid, kvno, key*2, begin,
1069 * end, primary, tktlen */
1070 toksize += RND(token->kad->ticket_len);
1071 break;
1072
1073 case RXRPC_SECURITY_RXK5:
1074 princ = &token->k5->client;
1075 toksize += 4 + princ->n_name_parts * 4;
1076 for (loop = 0; loop < princ->n_name_parts; loop++)
1077 toksize += RND(strlen(princ->name_parts[loop]));
1078 toksize += 4 + RND(strlen(princ->realm));
1079
1080 princ = &token->k5->server;
1081 toksize += 4 + princ->n_name_parts * 4;
1082 for (loop = 0; loop < princ->n_name_parts; loop++)
1083 toksize += RND(strlen(princ->name_parts[loop]));
1084 toksize += 4 + RND(strlen(princ->realm));
1085
1086 toksize += 8 + RND(token->k5->session.data_len);
1087
1088 toksize += 4 * 8 + 2 * 4;
1089
1090 toksize += 4 + token->k5->n_addresses * 8;
1091 for (loop = 0; loop < token->k5->n_addresses; loop++)
1092 toksize += RND(token->k5->addresses[loop].data_len);
1093
1094 toksize += 4 + RND(token->k5->ticket_len);
1095 toksize += 4 + RND(token->k5->ticket2_len);
1096
1097 toksize += 4 + token->k5->n_authdata * 8;
1098 for (loop = 0; loop < token->k5->n_authdata; loop++)
1099 toksize += RND(token->k5->authdata[loop].data_len);
1100 break;
1101
1102 default: /* we have a ticket we can't encode */
1103 BUG();
1104 continue;
1105 }
1106
1107 _debug("token[%u]: toksize=%u", ntoks, toksize);
1108 ASSERTCMP(toksize, <=, AFSTOKEN_LENGTH_MAX);
1109
1110 toksizes[ntoks++] = toksize;
1111 size += toksize + 4; /* each token has a length word */
1112 }
1113
1114#undef RND
1115
1116 if (!buffer || buflen < size)
1117 return size;
1118
1119 xdr = (__be32 __user *) buffer;
1120 zero = 0;
1121#define ENCODE(x) \
1122 do { \
1123 __be32 y = htonl(x); \
1124 if (put_user(y, xdr++) < 0) \
1125 goto fault; \
1126 } while(0)
1127#define ENCODE_DATA(l, s) \
1128 do { \
1129 u32 _l = (l); \
1130 ENCODE(l); \
1131 if (copy_to_user(xdr, (s), _l) != 0) \
1132 goto fault; \
1133 if (_l & 3 && \
1134 copy_to_user((u8 __user *)xdr + _l, &zero, 4 - (_l & 3)) != 0) \
1135 goto fault; \
1136 xdr += (_l + 3) >> 2; \
1137 } while(0)
1138#define ENCODE64(x) \
1139 do { \
1140 __be64 y = cpu_to_be64(x); \
1141 if (copy_to_user(xdr, &y, 8) != 0) \
1142 goto fault; \
1143 xdr += 8 >> 2; \
1144 } while(0)
1145#define ENCODE_STR(s) \
1146 do { \
1147 const char *_s = (s); \
1148 ENCODE_DATA(strlen(_s), _s); \
1149 } while(0)
1150
1151 ENCODE(0); /* flags */
1152 ENCODE_DATA(cnlen, key->description + 4); /* cellname */
1153 ENCODE(ntoks);
1154
1155 tok = 0;
1156 for (token = key->payload.data[0]; token; token = token->next) {
1157 toksize = toksizes[tok++];
1158 ENCODE(toksize);
1159 oldxdr = xdr;
1160 ENCODE(token->security_index);
1161
1162 switch (token->security_index) {
1163 case RXRPC_SECURITY_RXKAD:
1164 ENCODE(token->kad->vice_id);
1165 ENCODE(token->kad->kvno);
1166 ENCODE_DATA(8, token->kad->session_key);
1167 ENCODE(token->kad->start);
1168 ENCODE(token->kad->expiry);
1169 ENCODE(token->kad->primary_flag);
1170 ENCODE_DATA(token->kad->ticket_len, token->kad->ticket);
1171 break;
1172
1173 case RXRPC_SECURITY_RXK5:
1174 princ = &token->k5->client;
1175 ENCODE(princ->n_name_parts);
1176 for (loop = 0; loop < princ->n_name_parts; loop++)
1177 ENCODE_STR(princ->name_parts[loop]);
1178 ENCODE_STR(princ->realm);
1179
1180 princ = &token->k5->server;
1181 ENCODE(princ->n_name_parts);
1182 for (loop = 0; loop < princ->n_name_parts; loop++)
1183 ENCODE_STR(princ->name_parts[loop]);
1184 ENCODE_STR(princ->realm);
1185
1186 ENCODE(token->k5->session.tag);
1187 ENCODE_DATA(token->k5->session.data_len,
1188 token->k5->session.data);
1189
1190 ENCODE64(token->k5->authtime);
1191 ENCODE64(token->k5->starttime);
1192 ENCODE64(token->k5->endtime);
1193 ENCODE64(token->k5->renew_till);
1194 ENCODE(token->k5->is_skey);
1195 ENCODE(token->k5->flags);
1196
1197 ENCODE(token->k5->n_addresses);
1198 for (loop = 0; loop < token->k5->n_addresses; loop++) {
1199 ENCODE(token->k5->addresses[loop].tag);
1200 ENCODE_DATA(token->k5->addresses[loop].data_len,
1201 token->k5->addresses[loop].data);
1202 }
1203
1204 ENCODE_DATA(token->k5->ticket_len, token->k5->ticket);
1205 ENCODE_DATA(token->k5->ticket2_len, token->k5->ticket2);
1206
1207 ENCODE(token->k5->n_authdata);
1208 for (loop = 0; loop < token->k5->n_authdata; loop++) {
1209 ENCODE(token->k5->authdata[loop].tag);
1210 ENCODE_DATA(token->k5->authdata[loop].data_len,
1211 token->k5->authdata[loop].data);
1212 }
1213 break;
1214
1215 default:
1216 BUG();
1217 break;
1218 }
1219
1220 ASSERTCMP((unsigned long)xdr - (unsigned long)oldxdr, ==,
1221 toksize);
1222 }
1223
1224#undef ENCODE_STR
1225#undef ENCODE_DATA
1226#undef ENCODE64
1227#undef ENCODE
1228
1229 ASSERTCMP(tok, ==, ntoks);
1230 ASSERTCMP((char __user *) xdr - buffer, ==, size);
1231 _leave(" = %zu", size);
1232 return size;
1233
1234fault:
1235 _leave(" = -EFAULT");
1236 return -EFAULT;
1237}