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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// 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@CAMBRIDGE.REDHAT.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_vet_description_s(const char *);
27static int rxrpc_preparse(struct key_preparsed_payload *);
28static int rxrpc_preparse_s(struct key_preparsed_payload *);
29static void rxrpc_free_preparse(struct key_preparsed_payload *);
30static void rxrpc_free_preparse_s(struct key_preparsed_payload *);
31static void rxrpc_destroy(struct key *);
32static void rxrpc_destroy_s(struct key *);
33static void rxrpc_describe(const struct key *, struct seq_file *);
34static long rxrpc_read(const struct key *, char __user *, size_t);
35
36/*
37 * rxrpc defined keys take an arbitrary string as the description and an
38 * arbitrary blob of data as the payload
39 */
40struct key_type key_type_rxrpc = {
41 .name = "rxrpc",
42 .flags = KEY_TYPE_NET_DOMAIN,
43 .preparse = rxrpc_preparse,
44 .free_preparse = rxrpc_free_preparse,
45 .instantiate = generic_key_instantiate,
46 .destroy = rxrpc_destroy,
47 .describe = rxrpc_describe,
48 .read = rxrpc_read,
49};
50EXPORT_SYMBOL(key_type_rxrpc);
51
52/*
53 * rxrpc server defined keys take "<serviceId>:<securityIndex>" as the
54 * description and an 8-byte decryption key as the payload
55 */
56struct key_type key_type_rxrpc_s = {
57 .name = "rxrpc_s",
58 .flags = KEY_TYPE_NET_DOMAIN,
59 .vet_description = rxrpc_vet_description_s,
60 .preparse = rxrpc_preparse_s,
61 .free_preparse = rxrpc_free_preparse_s,
62 .instantiate = generic_key_instantiate,
63 .destroy = rxrpc_destroy_s,
64 .describe = rxrpc_describe,
65};
66
67/*
68 * Vet the description for an RxRPC server key
69 */
70static int rxrpc_vet_description_s(const char *desc)
71{
72 unsigned long num;
73 char *p;
74
75 num = simple_strtoul(desc, &p, 10);
76 if (*p != ':' || num > 65535)
77 return -EINVAL;
78 num = simple_strtoul(p + 1, &p, 10);
79 if (*p || num < 1 || num > 255)
80 return -EINVAL;
81 return 0;
82}
83
84/*
85 * parse an RxKAD type XDR format token
86 * - the caller guarantees we have at least 4 words
87 */
88static int rxrpc_preparse_xdr_rxkad(struct key_preparsed_payload *prep,
89 size_t datalen,
90 const __be32 *xdr, unsigned int toklen)
91{
92 struct rxrpc_key_token *token, **pptoken;
93 time64_t expiry;
94 size_t plen;
95 u32 tktlen;
96
97 _enter(",{%x,%x,%x,%x},%u",
98 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
99 toklen);
100
101 if (toklen <= 8 * 4)
102 return -EKEYREJECTED;
103 tktlen = ntohl(xdr[7]);
104 _debug("tktlen: %x", tktlen);
105 if (tktlen > AFSTOKEN_RK_TIX_MAX)
106 return -EKEYREJECTED;
107 if (toklen < 8 * 4 + tktlen)
108 return -EKEYREJECTED;
109
110 plen = sizeof(*token) + sizeof(*token->kad) + tktlen;
111 prep->quotalen = datalen + plen;
112
113 plen -= sizeof(*token);
114 token = kzalloc(sizeof(*token), GFP_KERNEL);
115 if (!token)
116 return -ENOMEM;
117
118 token->kad = kzalloc(plen, GFP_KERNEL);
119 if (!token->kad) {
120 kfree(token);
121 return -ENOMEM;
122 }
123
124 token->security_index = RXRPC_SECURITY_RXKAD;
125 token->kad->ticket_len = tktlen;
126 token->kad->vice_id = ntohl(xdr[0]);
127 token->kad->kvno = ntohl(xdr[1]);
128 token->kad->start = ntohl(xdr[4]);
129 token->kad->expiry = ntohl(xdr[5]);
130 token->kad->primary_flag = ntohl(xdr[6]);
131 memcpy(&token->kad->session_key, &xdr[2], 8);
132 memcpy(&token->kad->ticket, &xdr[8], tktlen);
133
134 _debug("SCIX: %u", token->security_index);
135 _debug("TLEN: %u", token->kad->ticket_len);
136 _debug("EXPY: %x", token->kad->expiry);
137 _debug("KVNO: %u", token->kad->kvno);
138 _debug("PRIM: %u", token->kad->primary_flag);
139 _debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
140 token->kad->session_key[0], token->kad->session_key[1],
141 token->kad->session_key[2], token->kad->session_key[3],
142 token->kad->session_key[4], token->kad->session_key[5],
143 token->kad->session_key[6], token->kad->session_key[7]);
144 if (token->kad->ticket_len >= 8)
145 _debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
146 token->kad->ticket[0], token->kad->ticket[1],
147 token->kad->ticket[2], token->kad->ticket[3],
148 token->kad->ticket[4], token->kad->ticket[5],
149 token->kad->ticket[6], token->kad->ticket[7]);
150
151 /* count the number of tokens attached */
152 prep->payload.data[1] = (void *)((unsigned long)prep->payload.data[1] + 1);
153
154 /* attach the data */
155 for (pptoken = (struct rxrpc_key_token **)&prep->payload.data[0];
156 *pptoken;
157 pptoken = &(*pptoken)->next)
158 continue;
159 *pptoken = token;
160 expiry = rxrpc_u32_to_time64(token->kad->expiry);
161 if (expiry < prep->expiry)
162 prep->expiry = 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, paddedlen;
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 paddedlen = (tmp + 3) & ~3;
251 if (paddedlen > toklen)
252 return -EINVAL;
253 princ->name_parts[loop] = kmalloc(tmp + 1, GFP_KERNEL);
254 if (!princ->name_parts[loop])
255 return -ENOMEM;
256 memcpy(princ->name_parts[loop], xdr, tmp);
257 princ->name_parts[loop][tmp] = 0;
258 toklen -= paddedlen;
259 xdr += paddedlen >> 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 paddedlen = (tmp + 3) & ~3;
269 if (paddedlen > toklen)
270 return -EINVAL;
271 princ->realm = kmalloc(tmp + 1, GFP_KERNEL);
272 if (!princ->realm)
273 return -ENOMEM;
274 memcpy(princ->realm, xdr, tmp);
275 princ->realm[tmp] = 0;
276 toklen -= paddedlen;
277 xdr += paddedlen >> 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, paddedlen;
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 paddedlen = (len + 3) & ~3;
311 if (paddedlen > toklen)
312 return -EINVAL;
313 td->data_len = len;
314
315 if (len > 0) {
316 td->data = kmemdup(xdr, len, GFP_KERNEL);
317 if (!td->data)
318 return -ENOMEM;
319 toklen -= paddedlen;
320 xdr += paddedlen >> 2;
321 }
322
323 _debug("tag %x len %x", td->tag, td->data_len);
324
325 *_xdr = xdr;
326 *_toklen = toklen;
327 _leave(" = 0 [toklen=%u]", toklen);
328 return 0;
329}
330
331/*
332 * extract an array of tagged data
333 */
334static int rxrpc_krb5_decode_tagged_array(struct krb5_tagged_data **_td,
335 u8 *_n_elem,
336 u8 max_n_elem,
337 size_t max_elem_size,
338 const __be32 **_xdr,
339 unsigned int *_toklen)
340{
341 struct krb5_tagged_data *td;
342 const __be32 *xdr = *_xdr;
343 unsigned int toklen = *_toklen, n_elem, loop;
344 int ret;
345
346 /* there must be at least one count */
347 if (toklen < 4)
348 return -EINVAL;
349
350 _enter(",,%u,%zu,{%x},%u",
351 max_n_elem, max_elem_size, ntohl(xdr[0]), toklen);
352
353 n_elem = ntohl(*xdr++);
354 toklen -= 4;
355 if (n_elem > max_n_elem)
356 return -EINVAL;
357 *_n_elem = n_elem;
358 if (n_elem > 0) {
359 if (toklen <= (n_elem + 1) * 4)
360 return -EINVAL;
361
362 _debug("n_elem %d", n_elem);
363
364 td = kcalloc(n_elem, sizeof(struct krb5_tagged_data),
365 GFP_KERNEL);
366 if (!td)
367 return -ENOMEM;
368 *_td = td;
369
370 for (loop = 0; loop < n_elem; loop++) {
371 ret = rxrpc_krb5_decode_tagged_data(&td[loop],
372 max_elem_size,
373 &xdr, &toklen);
374 if (ret < 0)
375 return ret;
376 }
377 }
378
379 *_xdr = xdr;
380 *_toklen = toklen;
381 _leave(" = 0 [toklen=%u]", toklen);
382 return 0;
383}
384
385/*
386 * extract a krb5 ticket
387 */
388static int rxrpc_krb5_decode_ticket(u8 **_ticket, u16 *_tktlen,
389 const __be32 **_xdr, unsigned int *_toklen)
390{
391 const __be32 *xdr = *_xdr;
392 unsigned int toklen = *_toklen, len, paddedlen;
393
394 /* there must be at least one length word */
395 if (toklen <= 4)
396 return -EINVAL;
397
398 _enter(",{%x},%u", ntohl(xdr[0]), toklen);
399
400 len = ntohl(*xdr++);
401 toklen -= 4;
402 if (len > AFSTOKEN_K5_TIX_MAX)
403 return -EINVAL;
404 paddedlen = (len + 3) & ~3;
405 if (paddedlen > toklen)
406 return -EINVAL;
407 *_tktlen = len;
408
409 _debug("ticket len %u", len);
410
411 if (len > 0) {
412 *_ticket = kmemdup(xdr, len, GFP_KERNEL);
413 if (!*_ticket)
414 return -ENOMEM;
415 toklen -= paddedlen;
416 xdr += paddedlen >> 2;
417 }
418
419 *_xdr = xdr;
420 *_toklen = toklen;
421 _leave(" = 0 [toklen=%u]", toklen);
422 return 0;
423}
424
425/*
426 * parse an RxK5 type XDR format token
427 * - the caller guarantees we have at least 4 words
428 */
429static int rxrpc_preparse_xdr_rxk5(struct key_preparsed_payload *prep,
430 size_t datalen,
431 const __be32 *xdr, unsigned int toklen)
432{
433 struct rxrpc_key_token *token, **pptoken;
434 struct rxk5_key *rxk5;
435 const __be32 *end_xdr = xdr + (toklen >> 2);
436 time64_t expiry;
437 int ret;
438
439 _enter(",{%x,%x,%x,%x},%u",
440 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
441 toklen);
442
443 /* reserve some payload space for this subkey - the length of the token
444 * is a reasonable approximation */
445 prep->quotalen = datalen + toklen;
446
447 token = kzalloc(sizeof(*token), GFP_KERNEL);
448 if (!token)
449 return -ENOMEM;
450
451 rxk5 = kzalloc(sizeof(*rxk5), GFP_KERNEL);
452 if (!rxk5) {
453 kfree(token);
454 return -ENOMEM;
455 }
456
457 token->security_index = RXRPC_SECURITY_RXK5;
458 token->k5 = rxk5;
459
460 /* extract the principals */
461 ret = rxrpc_krb5_decode_principal(&rxk5->client, &xdr, &toklen);
462 if (ret < 0)
463 goto error;
464 ret = rxrpc_krb5_decode_principal(&rxk5->server, &xdr, &toklen);
465 if (ret < 0)
466 goto error;
467
468 /* extract the session key and the encoding type (the tag field ->
469 * ENCTYPE_xxx) */
470 ret = rxrpc_krb5_decode_tagged_data(&rxk5->session, AFSTOKEN_DATA_MAX,
471 &xdr, &toklen);
472 if (ret < 0)
473 goto error;
474
475 if (toklen < 4 * 8 + 2 * 4)
476 goto inval;
477 rxk5->authtime = be64_to_cpup((const __be64 *) xdr);
478 xdr += 2;
479 rxk5->starttime = be64_to_cpup((const __be64 *) xdr);
480 xdr += 2;
481 rxk5->endtime = be64_to_cpup((const __be64 *) xdr);
482 xdr += 2;
483 rxk5->renew_till = be64_to_cpup((const __be64 *) xdr);
484 xdr += 2;
485 rxk5->is_skey = ntohl(*xdr++);
486 rxk5->flags = ntohl(*xdr++);
487 toklen -= 4 * 8 + 2 * 4;
488
489 _debug("times: a=%llx s=%llx e=%llx rt=%llx",
490 rxk5->authtime, rxk5->starttime, rxk5->endtime,
491 rxk5->renew_till);
492 _debug("is_skey=%x flags=%x", rxk5->is_skey, rxk5->flags);
493
494 /* extract the permitted client addresses */
495 ret = rxrpc_krb5_decode_tagged_array(&rxk5->addresses,
496 &rxk5->n_addresses,
497 AFSTOKEN_K5_ADDRESSES_MAX,
498 AFSTOKEN_DATA_MAX,
499 &xdr, &toklen);
500 if (ret < 0)
501 goto error;
502
503 ASSERTCMP((end_xdr - xdr) << 2, ==, toklen);
504
505 /* extract the tickets */
506 ret = rxrpc_krb5_decode_ticket(&rxk5->ticket, &rxk5->ticket_len,
507 &xdr, &toklen);
508 if (ret < 0)
509 goto error;
510 ret = rxrpc_krb5_decode_ticket(&rxk5->ticket2, &rxk5->ticket2_len,
511 &xdr, &toklen);
512 if (ret < 0)
513 goto error;
514
515 ASSERTCMP((end_xdr - xdr) << 2, ==, toklen);
516
517 /* extract the typed auth data */
518 ret = rxrpc_krb5_decode_tagged_array(&rxk5->authdata,
519 &rxk5->n_authdata,
520 AFSTOKEN_K5_AUTHDATA_MAX,
521 AFSTOKEN_BDATALN_MAX,
522 &xdr, &toklen);
523 if (ret < 0)
524 goto error;
525
526 ASSERTCMP((end_xdr - xdr) << 2, ==, toklen);
527
528 if (toklen != 0)
529 goto inval;
530
531 /* attach the payload */
532 for (pptoken = (struct rxrpc_key_token **)&prep->payload.data[0];
533 *pptoken;
534 pptoken = &(*pptoken)->next)
535 continue;
536 *pptoken = token;
537 expiry = rxrpc_u32_to_time64(token->k5->endtime);
538 if (expiry < prep->expiry)
539 prep->expiry = expiry;
540
541 _leave(" = 0");
542 return 0;
543
544inval:
545 ret = -EINVAL;
546error:
547 rxrpc_rxk5_free(rxk5);
548 kfree(token);
549 _leave(" = %d", ret);
550 return ret;
551}
552
553/*
554 * attempt to parse the data as the XDR format
555 * - the caller guarantees we have more than 7 words
556 */
557static int rxrpc_preparse_xdr(struct key_preparsed_payload *prep)
558{
559 const __be32 *xdr = prep->data, *token;
560 const char *cp;
561 unsigned int len, paddedlen, loop, ntoken, toklen, sec_ix;
562 size_t datalen = prep->datalen;
563 int ret;
564
565 _enter(",{%x,%x,%x,%x},%zu",
566 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
567 prep->datalen);
568
569 if (datalen > AFSTOKEN_LENGTH_MAX)
570 goto not_xdr;
571
572 /* XDR is an array of __be32's */
573 if (datalen & 3)
574 goto not_xdr;
575
576 /* the flags should be 0 (the setpag bit must be handled by
577 * userspace) */
578 if (ntohl(*xdr++) != 0)
579 goto not_xdr;
580 datalen -= 4;
581
582 /* check the cell name */
583 len = ntohl(*xdr++);
584 if (len < 1 || len > AFSTOKEN_CELL_MAX)
585 goto not_xdr;
586 datalen -= 4;
587 paddedlen = (len + 3) & ~3;
588 if (paddedlen > datalen)
589 goto not_xdr;
590
591 cp = (const char *) xdr;
592 for (loop = 0; loop < len; loop++)
593 if (!isprint(cp[loop]))
594 goto not_xdr;
595 for (; loop < paddedlen; loop++)
596 if (cp[loop])
597 goto not_xdr;
598 _debug("cellname: [%u/%u] '%*.*s'",
599 len, paddedlen, len, len, (const char *) xdr);
600 datalen -= paddedlen;
601 xdr += paddedlen >> 2;
602
603 /* get the token count */
604 if (datalen < 12)
605 goto not_xdr;
606 ntoken = ntohl(*xdr++);
607 datalen -= 4;
608 _debug("ntoken: %x", ntoken);
609 if (ntoken < 1 || ntoken > AFSTOKEN_MAX)
610 goto not_xdr;
611
612 /* check each token wrapper */
613 token = xdr;
614 loop = ntoken;
615 do {
616 if (datalen < 8)
617 goto not_xdr;
618 toklen = ntohl(*xdr++);
619 sec_ix = ntohl(*xdr);
620 datalen -= 4;
621 _debug("token: [%x/%zx] %x", toklen, datalen, sec_ix);
622 paddedlen = (toklen + 3) & ~3;
623 if (toklen < 20 || toklen > datalen || paddedlen > datalen)
624 goto not_xdr;
625 datalen -= paddedlen;
626 xdr += paddedlen >> 2;
627
628 } while (--loop > 0);
629
630 _debug("remainder: %zu", datalen);
631 if (datalen != 0)
632 goto not_xdr;
633
634 /* okay: we're going to assume it's valid XDR format
635 * - we ignore the cellname, relying on the key to be correctly named
636 */
637 do {
638 xdr = token;
639 toklen = ntohl(*xdr++);
640 token = xdr + ((toklen + 3) >> 2);
641 sec_ix = ntohl(*xdr++);
642 toklen -= 4;
643
644 _debug("TOKEN type=%u [%p-%p]", sec_ix, xdr, token);
645
646 switch (sec_ix) {
647 case RXRPC_SECURITY_RXKAD:
648 ret = rxrpc_preparse_xdr_rxkad(prep, datalen, xdr, toklen);
649 if (ret != 0)
650 goto error;
651 break;
652
653 case RXRPC_SECURITY_RXK5:
654 ret = rxrpc_preparse_xdr_rxk5(prep, datalen, xdr, toklen);
655 if (ret != 0)
656 goto error;
657 break;
658
659 default:
660 ret = -EPROTONOSUPPORT;
661 goto error;
662 }
663
664 } while (--ntoken > 0);
665
666 _leave(" = 0");
667 return 0;
668
669not_xdr:
670 _leave(" = -EPROTO");
671 return -EPROTO;
672error:
673 _leave(" = %d", ret);
674 return ret;
675}
676
677/*
678 * Preparse an rxrpc defined key.
679 *
680 * Data should be of the form:
681 * OFFSET LEN CONTENT
682 * 0 4 key interface version number
683 * 4 2 security index (type)
684 * 6 2 ticket length
685 * 8 4 key expiry time (time_t)
686 * 12 4 kvno
687 * 16 8 session key
688 * 24 [len] ticket
689 *
690 * if no data is provided, then a no-security key is made
691 */
692static int rxrpc_preparse(struct key_preparsed_payload *prep)
693{
694 const struct rxrpc_key_data_v1 *v1;
695 struct rxrpc_key_token *token, **pp;
696 time64_t expiry;
697 size_t plen;
698 u32 kver;
699 int ret;
700
701 _enter("%zu", prep->datalen);
702
703 /* handle a no-security key */
704 if (!prep->data && prep->datalen == 0)
705 return 0;
706
707 /* determine if the XDR payload format is being used */
708 if (prep->datalen > 7 * 4) {
709 ret = rxrpc_preparse_xdr(prep);
710 if (ret != -EPROTO)
711 return ret;
712 }
713
714 /* get the key interface version number */
715 ret = -EINVAL;
716 if (prep->datalen <= 4 || !prep->data)
717 goto error;
718 memcpy(&kver, prep->data, sizeof(kver));
719 prep->data += sizeof(kver);
720 prep->datalen -= sizeof(kver);
721
722 _debug("KEY I/F VERSION: %u", kver);
723
724 ret = -EKEYREJECTED;
725 if (kver != 1)
726 goto error;
727
728 /* deal with a version 1 key */
729 ret = -EINVAL;
730 if (prep->datalen < sizeof(*v1))
731 goto error;
732
733 v1 = prep->data;
734 if (prep->datalen != sizeof(*v1) + v1->ticket_length)
735 goto error;
736
737 _debug("SCIX: %u", v1->security_index);
738 _debug("TLEN: %u", v1->ticket_length);
739 _debug("EXPY: %x", v1->expiry);
740 _debug("KVNO: %u", v1->kvno);
741 _debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
742 v1->session_key[0], v1->session_key[1],
743 v1->session_key[2], v1->session_key[3],
744 v1->session_key[4], v1->session_key[5],
745 v1->session_key[6], v1->session_key[7]);
746 if (v1->ticket_length >= 8)
747 _debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
748 v1->ticket[0], v1->ticket[1],
749 v1->ticket[2], v1->ticket[3],
750 v1->ticket[4], v1->ticket[5],
751 v1->ticket[6], v1->ticket[7]);
752
753 ret = -EPROTONOSUPPORT;
754 if (v1->security_index != RXRPC_SECURITY_RXKAD)
755 goto error;
756
757 plen = sizeof(*token->kad) + v1->ticket_length;
758 prep->quotalen = plen + sizeof(*token);
759
760 ret = -ENOMEM;
761 token = kzalloc(sizeof(*token), GFP_KERNEL);
762 if (!token)
763 goto error;
764 token->kad = kzalloc(plen, GFP_KERNEL);
765 if (!token->kad)
766 goto error_free;
767
768 token->security_index = RXRPC_SECURITY_RXKAD;
769 token->kad->ticket_len = v1->ticket_length;
770 token->kad->expiry = v1->expiry;
771 token->kad->kvno = v1->kvno;
772 memcpy(&token->kad->session_key, &v1->session_key, 8);
773 memcpy(&token->kad->ticket, v1->ticket, v1->ticket_length);
774
775 /* count the number of tokens attached */
776 prep->payload.data[1] = (void *)((unsigned long)prep->payload.data[1] + 1);
777
778 /* attach the data */
779 pp = (struct rxrpc_key_token **)&prep->payload.data[0];
780 while (*pp)
781 pp = &(*pp)->next;
782 *pp = token;
783 expiry = rxrpc_u32_to_time64(token->kad->expiry);
784 if (expiry < prep->expiry)
785 prep->expiry = expiry;
786 token = NULL;
787 ret = 0;
788
789error_free:
790 kfree(token);
791error:
792 return ret;
793}
794
795/*
796 * Free token list.
797 */
798static void rxrpc_free_token_list(struct rxrpc_key_token *token)
799{
800 struct rxrpc_key_token *next;
801
802 for (; token; token = next) {
803 next = token->next;
804 switch (token->security_index) {
805 case RXRPC_SECURITY_RXKAD:
806 kfree(token->kad);
807 break;
808 case RXRPC_SECURITY_RXK5:
809 if (token->k5)
810 rxrpc_rxk5_free(token->k5);
811 break;
812 default:
813 pr_err("Unknown token type %x on rxrpc key\n",
814 token->security_index);
815 BUG();
816 }
817
818 kfree(token);
819 }
820}
821
822/*
823 * Clean up preparse data.
824 */
825static void rxrpc_free_preparse(struct key_preparsed_payload *prep)
826{
827 rxrpc_free_token_list(prep->payload.data[0]);
828}
829
830/*
831 * Preparse a server secret key.
832 *
833 * The data should be the 8-byte secret key.
834 */
835static int rxrpc_preparse_s(struct key_preparsed_payload *prep)
836{
837 struct crypto_skcipher *ci;
838
839 _enter("%zu", prep->datalen);
840
841 if (prep->datalen != 8)
842 return -EINVAL;
843
844 memcpy(&prep->payload.data[2], prep->data, 8);
845
846 ci = crypto_alloc_skcipher("pcbc(des)", 0, CRYPTO_ALG_ASYNC);
847 if (IS_ERR(ci)) {
848 _leave(" = %ld", PTR_ERR(ci));
849 return PTR_ERR(ci);
850 }
851
852 if (crypto_skcipher_setkey(ci, prep->data, 8) < 0)
853 BUG();
854
855 prep->payload.data[0] = ci;
856 _leave(" = 0");
857 return 0;
858}
859
860/*
861 * Clean up preparse data.
862 */
863static void rxrpc_free_preparse_s(struct key_preparsed_payload *prep)
864{
865 if (prep->payload.data[0])
866 crypto_free_skcipher(prep->payload.data[0]);
867}
868
869/*
870 * dispose of the data dangling from the corpse of a rxrpc key
871 */
872static void rxrpc_destroy(struct key *key)
873{
874 rxrpc_free_token_list(key->payload.data[0]);
875}
876
877/*
878 * dispose of the data dangling from the corpse of a rxrpc key
879 */
880static void rxrpc_destroy_s(struct key *key)
881{
882 if (key->payload.data[0]) {
883 crypto_free_skcipher(key->payload.data[0]);
884 key->payload.data[0] = NULL;
885 }
886}
887
888/*
889 * describe the rxrpc key
890 */
891static void rxrpc_describe(const struct key *key, struct seq_file *m)
892{
893 seq_puts(m, key->description);
894}
895
896/*
897 * grab the security key for a socket
898 */
899int rxrpc_request_key(struct rxrpc_sock *rx, char __user *optval, int optlen)
900{
901 struct key *key;
902 char *description;
903
904 _enter("");
905
906 if (optlen <= 0 || optlen > PAGE_SIZE - 1)
907 return -EINVAL;
908
909 description = memdup_user_nul(optval, optlen);
910 if (IS_ERR(description))
911 return PTR_ERR(description);
912
913 key = request_key_net(&key_type_rxrpc, description, sock_net(&rx->sk), NULL);
914 if (IS_ERR(key)) {
915 kfree(description);
916 _leave(" = %ld", PTR_ERR(key));
917 return PTR_ERR(key);
918 }
919
920 rx->key = key;
921 kfree(description);
922 _leave(" = 0 [key %x]", key->serial);
923 return 0;
924}
925
926/*
927 * grab the security keyring for a server socket
928 */
929int rxrpc_server_keyring(struct rxrpc_sock *rx, char __user *optval,
930 int optlen)
931{
932 struct key *key;
933 char *description;
934
935 _enter("");
936
937 if (optlen <= 0 || optlen > PAGE_SIZE - 1)
938 return -EINVAL;
939
940 description = memdup_user_nul(optval, optlen);
941 if (IS_ERR(description))
942 return PTR_ERR(description);
943
944 key = request_key_net(&key_type_keyring, description, sock_net(&rx->sk), NULL);
945 if (IS_ERR(key)) {
946 kfree(description);
947 _leave(" = %ld", PTR_ERR(key));
948 return PTR_ERR(key);
949 }
950
951 rx->securities = key;
952 kfree(description);
953 _leave(" = 0 [key %x]", key->serial);
954 return 0;
955}
956
957/*
958 * generate a server data key
959 */
960int rxrpc_get_server_data_key(struct rxrpc_connection *conn,
961 const void *session_key,
962 time64_t expiry,
963 u32 kvno)
964{
965 const struct cred *cred = current_cred();
966 struct key *key;
967 int ret;
968
969 struct {
970 u32 kver;
971 struct rxrpc_key_data_v1 v1;
972 } data;
973
974 _enter("");
975
976 key = key_alloc(&key_type_rxrpc, "x",
977 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, 0,
978 KEY_ALLOC_NOT_IN_QUOTA, NULL);
979 if (IS_ERR(key)) {
980 _leave(" = -ENOMEM [alloc %ld]", PTR_ERR(key));
981 return -ENOMEM;
982 }
983
984 _debug("key %d", key_serial(key));
985
986 data.kver = 1;
987 data.v1.security_index = RXRPC_SECURITY_RXKAD;
988 data.v1.ticket_length = 0;
989 data.v1.expiry = rxrpc_time64_to_u32(expiry);
990 data.v1.kvno = 0;
991
992 memcpy(&data.v1.session_key, session_key, sizeof(data.v1.session_key));
993
994 ret = key_instantiate_and_link(key, &data, sizeof(data), NULL, NULL);
995 if (ret < 0)
996 goto error;
997
998 conn->params.key = key;
999 _leave(" = 0 [%d]", key_serial(key));
1000 return 0;
1001
1002error:
1003 key_revoke(key);
1004 key_put(key);
1005 _leave(" = -ENOMEM [ins %d]", ret);
1006 return -ENOMEM;
1007}
1008EXPORT_SYMBOL(rxrpc_get_server_data_key);
1009
1010/**
1011 * rxrpc_get_null_key - Generate a null RxRPC key
1012 * @keyname: The name to give the key.
1013 *
1014 * Generate a null RxRPC key that can be used to indicate anonymous security is
1015 * required for a particular domain.
1016 */
1017struct key *rxrpc_get_null_key(const char *keyname)
1018{
1019 const struct cred *cred = current_cred();
1020 struct key *key;
1021 int ret;
1022
1023 key = key_alloc(&key_type_rxrpc, keyname,
1024 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
1025 KEY_POS_SEARCH, KEY_ALLOC_NOT_IN_QUOTA, NULL);
1026 if (IS_ERR(key))
1027 return key;
1028
1029 ret = key_instantiate_and_link(key, NULL, 0, NULL, NULL);
1030 if (ret < 0) {
1031 key_revoke(key);
1032 key_put(key);
1033 return ERR_PTR(ret);
1034 }
1035
1036 return key;
1037}
1038EXPORT_SYMBOL(rxrpc_get_null_key);
1039
1040/*
1041 * read the contents of an rxrpc key
1042 * - this returns the result in XDR form
1043 */
1044static long rxrpc_read(const struct key *key,
1045 char __user *buffer, size_t buflen)
1046{
1047 const struct rxrpc_key_token *token;
1048 const struct krb5_principal *princ;
1049 size_t size;
1050 __be32 __user *xdr, *oldxdr;
1051 u32 cnlen, toksize, ntoks, tok, zero;
1052 u16 toksizes[AFSTOKEN_MAX];
1053 int loop;
1054
1055 _enter("");
1056
1057 /* we don't know what form we should return non-AFS keys in */
1058 if (memcmp(key->description, "afs@", 4) != 0)
1059 return -EOPNOTSUPP;
1060 cnlen = strlen(key->description + 4);
1061
1062#define RND(X) (((X) + 3) & ~3)
1063
1064 /* AFS keys we return in XDR form, so we need to work out the size of
1065 * the XDR */
1066 size = 2 * 4; /* flags, cellname len */
1067 size += RND(cnlen); /* cellname */
1068 size += 1 * 4; /* token count */
1069
1070 ntoks = 0;
1071 for (token = key->payload.data[0]; token; token = token->next) {
1072 toksize = 4; /* sec index */
1073
1074 switch (token->security_index) {
1075 case RXRPC_SECURITY_RXKAD:
1076 toksize += 9 * 4; /* viceid, kvno, key*2 + len, begin,
1077 * end, primary, tktlen */
1078 toksize += RND(token->kad->ticket_len);
1079 break;
1080
1081 case RXRPC_SECURITY_RXK5:
1082 princ = &token->k5->client;
1083 toksize += 4 + princ->n_name_parts * 4;
1084 for (loop = 0; loop < princ->n_name_parts; loop++)
1085 toksize += RND(strlen(princ->name_parts[loop]));
1086 toksize += 4 + RND(strlen(princ->realm));
1087
1088 princ = &token->k5->server;
1089 toksize += 4 + princ->n_name_parts * 4;
1090 for (loop = 0; loop < princ->n_name_parts; loop++)
1091 toksize += RND(strlen(princ->name_parts[loop]));
1092 toksize += 4 + RND(strlen(princ->realm));
1093
1094 toksize += 8 + RND(token->k5->session.data_len);
1095
1096 toksize += 4 * 8 + 2 * 4;
1097
1098 toksize += 4 + token->k5->n_addresses * 8;
1099 for (loop = 0; loop < token->k5->n_addresses; loop++)
1100 toksize += RND(token->k5->addresses[loop].data_len);
1101
1102 toksize += 4 + RND(token->k5->ticket_len);
1103 toksize += 4 + RND(token->k5->ticket2_len);
1104
1105 toksize += 4 + token->k5->n_authdata * 8;
1106 for (loop = 0; loop < token->k5->n_authdata; loop++)
1107 toksize += RND(token->k5->authdata[loop].data_len);
1108 break;
1109
1110 default: /* we have a ticket we can't encode */
1111 BUG();
1112 continue;
1113 }
1114
1115 _debug("token[%u]: toksize=%u", ntoks, toksize);
1116 ASSERTCMP(toksize, <=, AFSTOKEN_LENGTH_MAX);
1117
1118 toksizes[ntoks++] = toksize;
1119 size += toksize + 4; /* each token has a length word */
1120 }
1121
1122#undef RND
1123
1124 if (!buffer || buflen < size)
1125 return size;
1126
1127 xdr = (__be32 __user *) buffer;
1128 zero = 0;
1129#define ENCODE(x) \
1130 do { \
1131 __be32 y = htonl(x); \
1132 if (put_user(y, xdr++) < 0) \
1133 goto fault; \
1134 } while(0)
1135#define ENCODE_DATA(l, s) \
1136 do { \
1137 u32 _l = (l); \
1138 ENCODE(l); \
1139 if (copy_to_user(xdr, (s), _l) != 0) \
1140 goto fault; \
1141 if (_l & 3 && \
1142 copy_to_user((u8 __user *)xdr + _l, &zero, 4 - (_l & 3)) != 0) \
1143 goto fault; \
1144 xdr += (_l + 3) >> 2; \
1145 } while(0)
1146#define ENCODE64(x) \
1147 do { \
1148 __be64 y = cpu_to_be64(x); \
1149 if (copy_to_user(xdr, &y, 8) != 0) \
1150 goto fault; \
1151 xdr += 8 >> 2; \
1152 } while(0)
1153#define ENCODE_STR(s) \
1154 do { \
1155 const char *_s = (s); \
1156 ENCODE_DATA(strlen(_s), _s); \
1157 } while(0)
1158
1159 ENCODE(0); /* flags */
1160 ENCODE_DATA(cnlen, key->description + 4); /* cellname */
1161 ENCODE(ntoks);
1162
1163 tok = 0;
1164 for (token = key->payload.data[0]; token; token = token->next) {
1165 toksize = toksizes[tok++];
1166 ENCODE(toksize);
1167 oldxdr = xdr;
1168 ENCODE(token->security_index);
1169
1170 switch (token->security_index) {
1171 case RXRPC_SECURITY_RXKAD:
1172 ENCODE(token->kad->vice_id);
1173 ENCODE(token->kad->kvno);
1174 ENCODE_DATA(8, token->kad->session_key);
1175 ENCODE(token->kad->start);
1176 ENCODE(token->kad->expiry);
1177 ENCODE(token->kad->primary_flag);
1178 ENCODE_DATA(token->kad->ticket_len, token->kad->ticket);
1179 break;
1180
1181 case RXRPC_SECURITY_RXK5:
1182 princ = &token->k5->client;
1183 ENCODE(princ->n_name_parts);
1184 for (loop = 0; loop < princ->n_name_parts; loop++)
1185 ENCODE_STR(princ->name_parts[loop]);
1186 ENCODE_STR(princ->realm);
1187
1188 princ = &token->k5->server;
1189 ENCODE(princ->n_name_parts);
1190 for (loop = 0; loop < princ->n_name_parts; loop++)
1191 ENCODE_STR(princ->name_parts[loop]);
1192 ENCODE_STR(princ->realm);
1193
1194 ENCODE(token->k5->session.tag);
1195 ENCODE_DATA(token->k5->session.data_len,
1196 token->k5->session.data);
1197
1198 ENCODE64(token->k5->authtime);
1199 ENCODE64(token->k5->starttime);
1200 ENCODE64(token->k5->endtime);
1201 ENCODE64(token->k5->renew_till);
1202 ENCODE(token->k5->is_skey);
1203 ENCODE(token->k5->flags);
1204
1205 ENCODE(token->k5->n_addresses);
1206 for (loop = 0; loop < token->k5->n_addresses; loop++) {
1207 ENCODE(token->k5->addresses[loop].tag);
1208 ENCODE_DATA(token->k5->addresses[loop].data_len,
1209 token->k5->addresses[loop].data);
1210 }
1211
1212 ENCODE_DATA(token->k5->ticket_len, token->k5->ticket);
1213 ENCODE_DATA(token->k5->ticket2_len, token->k5->ticket2);
1214
1215 ENCODE(token->k5->n_authdata);
1216 for (loop = 0; loop < token->k5->n_authdata; loop++) {
1217 ENCODE(token->k5->authdata[loop].tag);
1218 ENCODE_DATA(token->k5->authdata[loop].data_len,
1219 token->k5->authdata[loop].data);
1220 }
1221 break;
1222
1223 default:
1224 BUG();
1225 break;
1226 }
1227
1228 ASSERTCMP((unsigned long)xdr - (unsigned long)oldxdr, ==,
1229 toksize);
1230 }
1231
1232#undef ENCODE_STR
1233#undef ENCODE_DATA
1234#undef ENCODE64
1235#undef ENCODE
1236
1237 ASSERTCMP(tok, ==, ntoks);
1238 ASSERTCMP((char __user *) xdr - buffer, ==, size);
1239 _leave(" = %zu", size);
1240 return size;
1241
1242fault:
1243 _leave(" = -EFAULT");
1244 return -EFAULT;
1245}