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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#include <linux/module.h>
16#include <linux/net.h>
17#include <linux/skbuff.h>
18#include <linux/key-type.h>
19#include <linux/crypto.h>
20#include <linux/ctype.h>
21#include <linux/slab.h>
22#include <net/sock.h>
23#include <net/af_rxrpc.h>
24#include <keys/rxrpc-type.h>
25#include <keys/user-type.h>
26#include "ar-internal.h"
27
28static int rxrpc_vet_description_s(const char *);
29static int rxrpc_instantiate(struct key *, struct key_preparsed_payload *);
30static int rxrpc_instantiate_s(struct key *, 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 .instantiate = rxrpc_instantiate,
43 .match = user_match,
44 .destroy = rxrpc_destroy,
45 .describe = rxrpc_describe,
46 .read = rxrpc_read,
47};
48EXPORT_SYMBOL(key_type_rxrpc);
49
50/*
51 * rxrpc server defined keys take "<serviceId>:<securityIndex>" as the
52 * description and an 8-byte decryption key as the payload
53 */
54struct key_type key_type_rxrpc_s = {
55 .name = "rxrpc_s",
56 .vet_description = rxrpc_vet_description_s,
57 .instantiate = rxrpc_instantiate_s,
58 .match = user_match,
59 .destroy = rxrpc_destroy_s,
60 .describe = rxrpc_describe,
61};
62
63/*
64 * Vet the description for an RxRPC server key
65 */
66static int rxrpc_vet_description_s(const char *desc)
67{
68 unsigned long num;
69 char *p;
70
71 num = simple_strtoul(desc, &p, 10);
72 if (*p != ':' || num > 65535)
73 return -EINVAL;
74 num = simple_strtoul(p + 1, &p, 10);
75 if (*p || num < 1 || num > 255)
76 return -EINVAL;
77 return 0;
78}
79
80/*
81 * parse an RxKAD type XDR format token
82 * - the caller guarantees we have at least 4 words
83 */
84static int rxrpc_instantiate_xdr_rxkad(struct key *key, const __be32 *xdr,
85 unsigned int toklen)
86{
87 struct rxrpc_key_token *token, **pptoken;
88 size_t plen;
89 u32 tktlen;
90 int ret;
91
92 _enter(",{%x,%x,%x,%x},%u",
93 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
94 toklen);
95
96 if (toklen <= 8 * 4)
97 return -EKEYREJECTED;
98 tktlen = ntohl(xdr[7]);
99 _debug("tktlen: %x", tktlen);
100 if (tktlen > AFSTOKEN_RK_TIX_MAX)
101 return -EKEYREJECTED;
102 if (toklen < 8 * 4 + tktlen)
103 return -EKEYREJECTED;
104
105 plen = sizeof(*token) + sizeof(*token->kad) + tktlen;
106 ret = key_payload_reserve(key, key->datalen + plen);
107 if (ret < 0)
108 return ret;
109
110 plen -= sizeof(*token);
111 token = kzalloc(sizeof(*token), GFP_KERNEL);
112 if (!token)
113 return -ENOMEM;
114
115 token->kad = kzalloc(plen, GFP_KERNEL);
116 if (!token->kad) {
117 kfree(token);
118 return -ENOMEM;
119 }
120
121 token->security_index = RXRPC_SECURITY_RXKAD;
122 token->kad->ticket_len = tktlen;
123 token->kad->vice_id = ntohl(xdr[0]);
124 token->kad->kvno = ntohl(xdr[1]);
125 token->kad->start = ntohl(xdr[4]);
126 token->kad->expiry = ntohl(xdr[5]);
127 token->kad->primary_flag = ntohl(xdr[6]);
128 memcpy(&token->kad->session_key, &xdr[2], 8);
129 memcpy(&token->kad->ticket, &xdr[8], tktlen);
130
131 _debug("SCIX: %u", token->security_index);
132 _debug("TLEN: %u", token->kad->ticket_len);
133 _debug("EXPY: %x", token->kad->expiry);
134 _debug("KVNO: %u", token->kad->kvno);
135 _debug("PRIM: %u", token->kad->primary_flag);
136 _debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
137 token->kad->session_key[0], token->kad->session_key[1],
138 token->kad->session_key[2], token->kad->session_key[3],
139 token->kad->session_key[4], token->kad->session_key[5],
140 token->kad->session_key[6], token->kad->session_key[7]);
141 if (token->kad->ticket_len >= 8)
142 _debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
143 token->kad->ticket[0], token->kad->ticket[1],
144 token->kad->ticket[2], token->kad->ticket[3],
145 token->kad->ticket[4], token->kad->ticket[5],
146 token->kad->ticket[6], token->kad->ticket[7]);
147
148 /* count the number of tokens attached */
149 key->type_data.x[0]++;
150
151 /* attach the data */
152 for (pptoken = (struct rxrpc_key_token **)&key->payload.data;
153 *pptoken;
154 pptoken = &(*pptoken)->next)
155 continue;
156 *pptoken = token;
157 if (token->kad->expiry < key->expiry)
158 key->expiry = token->kad->expiry;
159
160 _leave(" = 0");
161 return 0;
162}
163
164static void rxrpc_free_krb5_principal(struct krb5_principal *princ)
165{
166 int loop;
167
168 if (princ->name_parts) {
169 for (loop = princ->n_name_parts - 1; loop >= 0; loop--)
170 kfree(princ->name_parts[loop]);
171 kfree(princ->name_parts);
172 }
173 kfree(princ->realm);
174}
175
176static void rxrpc_free_krb5_tagged(struct krb5_tagged_data *td)
177{
178 kfree(td->data);
179}
180
181/*
182 * free up an RxK5 token
183 */
184static void rxrpc_rxk5_free(struct rxk5_key *rxk5)
185{
186 int loop;
187
188 rxrpc_free_krb5_principal(&rxk5->client);
189 rxrpc_free_krb5_principal(&rxk5->server);
190 rxrpc_free_krb5_tagged(&rxk5->session);
191
192 if (rxk5->addresses) {
193 for (loop = rxk5->n_addresses - 1; loop >= 0; loop--)
194 rxrpc_free_krb5_tagged(&rxk5->addresses[loop]);
195 kfree(rxk5->addresses);
196 }
197 if (rxk5->authdata) {
198 for (loop = rxk5->n_authdata - 1; loop >= 0; loop--)
199 rxrpc_free_krb5_tagged(&rxk5->authdata[loop]);
200 kfree(rxk5->authdata);
201 }
202
203 kfree(rxk5->ticket);
204 kfree(rxk5->ticket2);
205 kfree(rxk5);
206}
207
208/*
209 * extract a krb5 principal
210 */
211static int rxrpc_krb5_decode_principal(struct krb5_principal *princ,
212 const __be32 **_xdr,
213 unsigned int *_toklen)
214{
215 const __be32 *xdr = *_xdr;
216 unsigned int toklen = *_toklen, n_parts, loop, tmp;
217
218 /* there must be at least one name, and at least #names+1 length
219 * words */
220 if (toklen <= 12)
221 return -EINVAL;
222
223 _enter(",{%x,%x,%x},%u",
224 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), toklen);
225
226 n_parts = ntohl(*xdr++);
227 toklen -= 4;
228 if (n_parts <= 0 || n_parts > AFSTOKEN_K5_COMPONENTS_MAX)
229 return -EINVAL;
230 princ->n_name_parts = n_parts;
231
232 if (toklen <= (n_parts + 1) * 4)
233 return -EINVAL;
234
235 princ->name_parts = kcalloc(n_parts, sizeof(char *), GFP_KERNEL);
236 if (!princ->name_parts)
237 return -ENOMEM;
238
239 for (loop = 0; loop < n_parts; loop++) {
240 if (toklen < 4)
241 return -EINVAL;
242 tmp = ntohl(*xdr++);
243 toklen -= 4;
244 if (tmp <= 0 || tmp > AFSTOKEN_STRING_MAX)
245 return -EINVAL;
246 if (tmp > toklen)
247 return -EINVAL;
248 princ->name_parts[loop] = kmalloc(tmp + 1, GFP_KERNEL);
249 if (!princ->name_parts[loop])
250 return -ENOMEM;
251 memcpy(princ->name_parts[loop], xdr, tmp);
252 princ->name_parts[loop][tmp] = 0;
253 tmp = (tmp + 3) & ~3;
254 toklen -= tmp;
255 xdr += tmp >> 2;
256 }
257
258 if (toklen < 4)
259 return -EINVAL;
260 tmp = ntohl(*xdr++);
261 toklen -= 4;
262 if (tmp <= 0 || tmp > AFSTOKEN_K5_REALM_MAX)
263 return -EINVAL;
264 if (tmp > toklen)
265 return -EINVAL;
266 princ->realm = kmalloc(tmp + 1, GFP_KERNEL);
267 if (!princ->realm)
268 return -ENOMEM;
269 memcpy(princ->realm, xdr, tmp);
270 princ->realm[tmp] = 0;
271 tmp = (tmp + 3) & ~3;
272 toklen -= tmp;
273 xdr += tmp >> 2;
274
275 _debug("%s/...@%s", princ->name_parts[0], princ->realm);
276
277 *_xdr = xdr;
278 *_toklen = toklen;
279 _leave(" = 0 [toklen=%u]", toklen);
280 return 0;
281}
282
283/*
284 * extract a piece of krb5 tagged data
285 */
286static int rxrpc_krb5_decode_tagged_data(struct krb5_tagged_data *td,
287 size_t max_data_size,
288 const __be32 **_xdr,
289 unsigned int *_toklen)
290{
291 const __be32 *xdr = *_xdr;
292 unsigned int toklen = *_toklen, len;
293
294 /* there must be at least one tag and one length word */
295 if (toklen <= 8)
296 return -EINVAL;
297
298 _enter(",%zu,{%x,%x},%u",
299 max_data_size, ntohl(xdr[0]), ntohl(xdr[1]), toklen);
300
301 td->tag = ntohl(*xdr++);
302 len = ntohl(*xdr++);
303 toklen -= 8;
304 if (len > max_data_size)
305 return -EINVAL;
306 td->data_len = len;
307
308 if (len > 0) {
309 td->data = kmemdup(xdr, len, GFP_KERNEL);
310 if (!td->data)
311 return -ENOMEM;
312 len = (len + 3) & ~3;
313 toklen -= len;
314 xdr += len >> 2;
315 }
316
317 _debug("tag %x len %x", td->tag, td->data_len);
318
319 *_xdr = xdr;
320 *_toklen = toklen;
321 _leave(" = 0 [toklen=%u]", toklen);
322 return 0;
323}
324
325/*
326 * extract an array of tagged data
327 */
328static int rxrpc_krb5_decode_tagged_array(struct krb5_tagged_data **_td,
329 u8 *_n_elem,
330 u8 max_n_elem,
331 size_t max_elem_size,
332 const __be32 **_xdr,
333 unsigned int *_toklen)
334{
335 struct krb5_tagged_data *td;
336 const __be32 *xdr = *_xdr;
337 unsigned int toklen = *_toklen, n_elem, loop;
338 int ret;
339
340 /* there must be at least one count */
341 if (toklen < 4)
342 return -EINVAL;
343
344 _enter(",,%u,%zu,{%x},%u",
345 max_n_elem, max_elem_size, ntohl(xdr[0]), toklen);
346
347 n_elem = ntohl(*xdr++);
348 toklen -= 4;
349 if (n_elem < 0 || n_elem > max_n_elem)
350 return -EINVAL;
351 *_n_elem = n_elem;
352 if (n_elem > 0) {
353 if (toklen <= (n_elem + 1) * 4)
354 return -EINVAL;
355
356 _debug("n_elem %d", n_elem);
357
358 td = kcalloc(n_elem, sizeof(struct krb5_tagged_data),
359 GFP_KERNEL);
360 if (!td)
361 return -ENOMEM;
362 *_td = td;
363
364 for (loop = 0; loop < n_elem; loop++) {
365 ret = rxrpc_krb5_decode_tagged_data(&td[loop],
366 max_elem_size,
367 &xdr, &toklen);
368 if (ret < 0)
369 return ret;
370 }
371 }
372
373 *_xdr = xdr;
374 *_toklen = toklen;
375 _leave(" = 0 [toklen=%u]", toklen);
376 return 0;
377}
378
379/*
380 * extract a krb5 ticket
381 */
382static int rxrpc_krb5_decode_ticket(u8 **_ticket, u16 *_tktlen,
383 const __be32 **_xdr, unsigned int *_toklen)
384{
385 const __be32 *xdr = *_xdr;
386 unsigned int toklen = *_toklen, len;
387
388 /* there must be at least one length word */
389 if (toklen <= 4)
390 return -EINVAL;
391
392 _enter(",{%x},%u", ntohl(xdr[0]), toklen);
393
394 len = ntohl(*xdr++);
395 toklen -= 4;
396 if (len > AFSTOKEN_K5_TIX_MAX)
397 return -EINVAL;
398 *_tktlen = len;
399
400 _debug("ticket len %u", len);
401
402 if (len > 0) {
403 *_ticket = kmemdup(xdr, len, GFP_KERNEL);
404 if (!*_ticket)
405 return -ENOMEM;
406 len = (len + 3) & ~3;
407 toklen -= len;
408 xdr += len >> 2;
409 }
410
411 *_xdr = xdr;
412 *_toklen = toklen;
413 _leave(" = 0 [toklen=%u]", toklen);
414 return 0;
415}
416
417/*
418 * parse an RxK5 type XDR format token
419 * - the caller guarantees we have at least 4 words
420 */
421static int rxrpc_instantiate_xdr_rxk5(struct key *key, const __be32 *xdr,
422 unsigned int toklen)
423{
424 struct rxrpc_key_token *token, **pptoken;
425 struct rxk5_key *rxk5;
426 const __be32 *end_xdr = xdr + (toklen >> 2);
427 int ret;
428
429 _enter(",{%x,%x,%x,%x},%u",
430 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
431 toklen);
432
433 /* reserve some payload space for this subkey - the length of the token
434 * is a reasonable approximation */
435 ret = key_payload_reserve(key, key->datalen + toklen);
436 if (ret < 0)
437 return ret;
438
439 token = kzalloc(sizeof(*token), GFP_KERNEL);
440 if (!token)
441 return -ENOMEM;
442
443 rxk5 = kzalloc(sizeof(*rxk5), GFP_KERNEL);
444 if (!rxk5) {
445 kfree(token);
446 return -ENOMEM;
447 }
448
449 token->security_index = RXRPC_SECURITY_RXK5;
450 token->k5 = rxk5;
451
452 /* extract the principals */
453 ret = rxrpc_krb5_decode_principal(&rxk5->client, &xdr, &toklen);
454 if (ret < 0)
455 goto error;
456 ret = rxrpc_krb5_decode_principal(&rxk5->server, &xdr, &toklen);
457 if (ret < 0)
458 goto error;
459
460 /* extract the session key and the encoding type (the tag field ->
461 * ENCTYPE_xxx) */
462 ret = rxrpc_krb5_decode_tagged_data(&rxk5->session, AFSTOKEN_DATA_MAX,
463 &xdr, &toklen);
464 if (ret < 0)
465 goto error;
466
467 if (toklen < 4 * 8 + 2 * 4)
468 goto inval;
469 rxk5->authtime = be64_to_cpup((const __be64 *) xdr);
470 xdr += 2;
471 rxk5->starttime = be64_to_cpup((const __be64 *) xdr);
472 xdr += 2;
473 rxk5->endtime = be64_to_cpup((const __be64 *) xdr);
474 xdr += 2;
475 rxk5->renew_till = be64_to_cpup((const __be64 *) xdr);
476 xdr += 2;
477 rxk5->is_skey = ntohl(*xdr++);
478 rxk5->flags = ntohl(*xdr++);
479 toklen -= 4 * 8 + 2 * 4;
480
481 _debug("times: a=%llx s=%llx e=%llx rt=%llx",
482 rxk5->authtime, rxk5->starttime, rxk5->endtime,
483 rxk5->renew_till);
484 _debug("is_skey=%x flags=%x", rxk5->is_skey, rxk5->flags);
485
486 /* extract the permitted client addresses */
487 ret = rxrpc_krb5_decode_tagged_array(&rxk5->addresses,
488 &rxk5->n_addresses,
489 AFSTOKEN_K5_ADDRESSES_MAX,
490 AFSTOKEN_DATA_MAX,
491 &xdr, &toklen);
492 if (ret < 0)
493 goto error;
494
495 ASSERTCMP((end_xdr - xdr) << 2, ==, toklen);
496
497 /* extract the tickets */
498 ret = rxrpc_krb5_decode_ticket(&rxk5->ticket, &rxk5->ticket_len,
499 &xdr, &toklen);
500 if (ret < 0)
501 goto error;
502 ret = rxrpc_krb5_decode_ticket(&rxk5->ticket2, &rxk5->ticket2_len,
503 &xdr, &toklen);
504 if (ret < 0)
505 goto error;
506
507 ASSERTCMP((end_xdr - xdr) << 2, ==, toklen);
508
509 /* extract the typed auth data */
510 ret = rxrpc_krb5_decode_tagged_array(&rxk5->authdata,
511 &rxk5->n_authdata,
512 AFSTOKEN_K5_AUTHDATA_MAX,
513 AFSTOKEN_BDATALN_MAX,
514 &xdr, &toklen);
515 if (ret < 0)
516 goto error;
517
518 ASSERTCMP((end_xdr - xdr) << 2, ==, toklen);
519
520 if (toklen != 0)
521 goto inval;
522
523 /* attach the payload to the key */
524 for (pptoken = (struct rxrpc_key_token **)&key->payload.data;
525 *pptoken;
526 pptoken = &(*pptoken)->next)
527 continue;
528 *pptoken = token;
529 if (token->kad->expiry < key->expiry)
530 key->expiry = token->kad->expiry;
531
532 _leave(" = 0");
533 return 0;
534
535inval:
536 ret = -EINVAL;
537error:
538 rxrpc_rxk5_free(rxk5);
539 kfree(token);
540 _leave(" = %d", ret);
541 return ret;
542}
543
544/*
545 * attempt to parse the data as the XDR format
546 * - the caller guarantees we have more than 7 words
547 */
548static int rxrpc_instantiate_xdr(struct key *key, const void *data, size_t datalen)
549{
550 const __be32 *xdr = data, *token;
551 const char *cp;
552 unsigned int len, tmp, loop, ntoken, toklen, sec_ix;
553 int ret;
554
555 _enter(",{%x,%x,%x,%x},%zu",
556 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
557 datalen);
558
559 if (datalen > AFSTOKEN_LENGTH_MAX)
560 goto not_xdr;
561
562 /* XDR is an array of __be32's */
563 if (datalen & 3)
564 goto not_xdr;
565
566 /* the flags should be 0 (the setpag bit must be handled by
567 * userspace) */
568 if (ntohl(*xdr++) != 0)
569 goto not_xdr;
570 datalen -= 4;
571
572 /* check the cell name */
573 len = ntohl(*xdr++);
574 if (len < 1 || len > AFSTOKEN_CELL_MAX)
575 goto not_xdr;
576 datalen -= 4;
577 tmp = (len + 3) & ~3;
578 if (tmp > datalen)
579 goto not_xdr;
580
581 cp = (const char *) xdr;
582 for (loop = 0; loop < len; loop++)
583 if (!isprint(cp[loop]))
584 goto not_xdr;
585 if (len < tmp)
586 for (; loop < tmp; loop++)
587 if (cp[loop])
588 goto not_xdr;
589 _debug("cellname: [%u/%u] '%*.*s'",
590 len, tmp, len, len, (const char *) xdr);
591 datalen -= tmp;
592 xdr += tmp >> 2;
593
594 /* get the token count */
595 if (datalen < 12)
596 goto not_xdr;
597 ntoken = ntohl(*xdr++);
598 datalen -= 4;
599 _debug("ntoken: %x", ntoken);
600 if (ntoken < 1 || ntoken > AFSTOKEN_MAX)
601 goto not_xdr;
602
603 /* check each token wrapper */
604 token = xdr;
605 loop = ntoken;
606 do {
607 if (datalen < 8)
608 goto not_xdr;
609 toklen = ntohl(*xdr++);
610 sec_ix = ntohl(*xdr);
611 datalen -= 4;
612 _debug("token: [%x/%zx] %x", toklen, datalen, sec_ix);
613 if (toklen < 20 || toklen > datalen)
614 goto not_xdr;
615 datalen -= (toklen + 3) & ~3;
616 xdr += (toklen + 3) >> 2;
617
618 } while (--loop > 0);
619
620 _debug("remainder: %zu", datalen);
621 if (datalen != 0)
622 goto not_xdr;
623
624 /* okay: we're going to assume it's valid XDR format
625 * - we ignore the cellname, relying on the key to be correctly named
626 */
627 do {
628 xdr = token;
629 toklen = ntohl(*xdr++);
630 token = xdr + ((toklen + 3) >> 2);
631 sec_ix = ntohl(*xdr++);
632 toklen -= 4;
633
634 _debug("TOKEN type=%u [%p-%p]", sec_ix, xdr, token);
635
636 switch (sec_ix) {
637 case RXRPC_SECURITY_RXKAD:
638 ret = rxrpc_instantiate_xdr_rxkad(key, xdr, toklen);
639 if (ret != 0)
640 goto error;
641 break;
642
643 case RXRPC_SECURITY_RXK5:
644 ret = rxrpc_instantiate_xdr_rxk5(key, xdr, toklen);
645 if (ret != 0)
646 goto error;
647 break;
648
649 default:
650 ret = -EPROTONOSUPPORT;
651 goto error;
652 }
653
654 } while (--ntoken > 0);
655
656 _leave(" = 0");
657 return 0;
658
659not_xdr:
660 _leave(" = -EPROTO");
661 return -EPROTO;
662error:
663 _leave(" = %d", ret);
664 return ret;
665}
666
667/*
668 * instantiate an rxrpc defined key
669 * data should be of the form:
670 * OFFSET LEN CONTENT
671 * 0 4 key interface version number
672 * 4 2 security index (type)
673 * 6 2 ticket length
674 * 8 4 key expiry time (time_t)
675 * 12 4 kvno
676 * 16 8 session key
677 * 24 [len] ticket
678 *
679 * if no data is provided, then a no-security key is made
680 */
681static int rxrpc_instantiate(struct key *key, struct key_preparsed_payload *prep)
682{
683 const struct rxrpc_key_data_v1 *v1;
684 struct rxrpc_key_token *token, **pp;
685 size_t plen;
686 u32 kver;
687 int ret;
688
689 _enter("{%x},,%zu", key_serial(key), prep->datalen);
690
691 /* handle a no-security key */
692 if (!prep->data && prep->datalen == 0)
693 return 0;
694
695 /* determine if the XDR payload format is being used */
696 if (prep->datalen > 7 * 4) {
697 ret = rxrpc_instantiate_xdr(key, prep->data, prep->datalen);
698 if (ret != -EPROTO)
699 return ret;
700 }
701
702 /* get the key interface version number */
703 ret = -EINVAL;
704 if (prep->datalen <= 4 || !prep->data)
705 goto error;
706 memcpy(&kver, prep->data, sizeof(kver));
707 prep->data += sizeof(kver);
708 prep->datalen -= sizeof(kver);
709
710 _debug("KEY I/F VERSION: %u", kver);
711
712 ret = -EKEYREJECTED;
713 if (kver != 1)
714 goto error;
715
716 /* deal with a version 1 key */
717 ret = -EINVAL;
718 if (prep->datalen < sizeof(*v1))
719 goto error;
720
721 v1 = prep->data;
722 if (prep->datalen != sizeof(*v1) + v1->ticket_length)
723 goto error;
724
725 _debug("SCIX: %u", v1->security_index);
726 _debug("TLEN: %u", v1->ticket_length);
727 _debug("EXPY: %x", v1->expiry);
728 _debug("KVNO: %u", v1->kvno);
729 _debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
730 v1->session_key[0], v1->session_key[1],
731 v1->session_key[2], v1->session_key[3],
732 v1->session_key[4], v1->session_key[5],
733 v1->session_key[6], v1->session_key[7]);
734 if (v1->ticket_length >= 8)
735 _debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
736 v1->ticket[0], v1->ticket[1],
737 v1->ticket[2], v1->ticket[3],
738 v1->ticket[4], v1->ticket[5],
739 v1->ticket[6], v1->ticket[7]);
740
741 ret = -EPROTONOSUPPORT;
742 if (v1->security_index != RXRPC_SECURITY_RXKAD)
743 goto error;
744
745 plen = sizeof(*token->kad) + v1->ticket_length;
746 ret = key_payload_reserve(key, plen + sizeof(*token));
747 if (ret < 0)
748 goto error;
749
750 ret = -ENOMEM;
751 token = kzalloc(sizeof(*token), GFP_KERNEL);
752 if (!token)
753 goto error;
754 token->kad = kzalloc(plen, GFP_KERNEL);
755 if (!token->kad)
756 goto error_free;
757
758 token->security_index = RXRPC_SECURITY_RXKAD;
759 token->kad->ticket_len = v1->ticket_length;
760 token->kad->expiry = v1->expiry;
761 token->kad->kvno = v1->kvno;
762 memcpy(&token->kad->session_key, &v1->session_key, 8);
763 memcpy(&token->kad->ticket, v1->ticket, v1->ticket_length);
764
765 /* attach the data */
766 key->type_data.x[0]++;
767
768 pp = (struct rxrpc_key_token **)&key->payload.data;
769 while (*pp)
770 pp = &(*pp)->next;
771 *pp = token;
772 if (token->kad->expiry < key->expiry)
773 key->expiry = token->kad->expiry;
774 token = NULL;
775 ret = 0;
776
777error_free:
778 kfree(token);
779error:
780 return ret;
781}
782
783/*
784 * instantiate a server secret key
785 * data should be a pointer to the 8-byte secret key
786 */
787static int rxrpc_instantiate_s(struct key *key,
788 struct key_preparsed_payload *prep)
789{
790 struct crypto_blkcipher *ci;
791
792 _enter("{%x},,%zu", key_serial(key), prep->datalen);
793
794 if (prep->datalen != 8)
795 return -EINVAL;
796
797 memcpy(&key->type_data, prep->data, 8);
798
799 ci = crypto_alloc_blkcipher("pcbc(des)", 0, CRYPTO_ALG_ASYNC);
800 if (IS_ERR(ci)) {
801 _leave(" = %ld", PTR_ERR(ci));
802 return PTR_ERR(ci);
803 }
804
805 if (crypto_blkcipher_setkey(ci, prep->data, 8) < 0)
806 BUG();
807
808 key->payload.data = ci;
809 _leave(" = 0");
810 return 0;
811}
812
813/*
814 * dispose of the data dangling from the corpse of a rxrpc key
815 */
816static void rxrpc_destroy(struct key *key)
817{
818 struct rxrpc_key_token *token;
819
820 while ((token = key->payload.data)) {
821 key->payload.data = token->next;
822 switch (token->security_index) {
823 case RXRPC_SECURITY_RXKAD:
824 kfree(token->kad);
825 break;
826 case RXRPC_SECURITY_RXK5:
827 if (token->k5)
828 rxrpc_rxk5_free(token->k5);
829 break;
830 default:
831 printk(KERN_ERR "Unknown token type %x on rxrpc key\n",
832 token->security_index);
833 BUG();
834 }
835
836 kfree(token);
837 }
838}
839
840/*
841 * dispose of the data dangling from the corpse of a rxrpc key
842 */
843static void rxrpc_destroy_s(struct key *key)
844{
845 if (key->payload.data) {
846 crypto_free_blkcipher(key->payload.data);
847 key->payload.data = NULL;
848 }
849}
850
851/*
852 * describe the rxrpc key
853 */
854static void rxrpc_describe(const struct key *key, struct seq_file *m)
855{
856 seq_puts(m, key->description);
857}
858
859/*
860 * grab the security key for a socket
861 */
862int rxrpc_request_key(struct rxrpc_sock *rx, char __user *optval, int optlen)
863{
864 struct key *key;
865 char *description;
866
867 _enter("");
868
869 if (optlen <= 0 || optlen > PAGE_SIZE - 1)
870 return -EINVAL;
871
872 description = kmalloc(optlen + 1, GFP_KERNEL);
873 if (!description)
874 return -ENOMEM;
875
876 if (copy_from_user(description, optval, optlen)) {
877 kfree(description);
878 return -EFAULT;
879 }
880 description[optlen] = 0;
881
882 key = request_key(&key_type_rxrpc, description, NULL);
883 if (IS_ERR(key)) {
884 kfree(description);
885 _leave(" = %ld", PTR_ERR(key));
886 return PTR_ERR(key);
887 }
888
889 rx->key = key;
890 kfree(description);
891 _leave(" = 0 [key %x]", key->serial);
892 return 0;
893}
894
895/*
896 * grab the security keyring for a server socket
897 */
898int rxrpc_server_keyring(struct rxrpc_sock *rx, char __user *optval,
899 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 = kmalloc(optlen + 1, GFP_KERNEL);
910 if (!description)
911 return -ENOMEM;
912
913 if (copy_from_user(description, optval, optlen)) {
914 kfree(description);
915 return -EFAULT;
916 }
917 description[optlen] = 0;
918
919 key = request_key(&key_type_keyring, description, NULL);
920 if (IS_ERR(key)) {
921 kfree(description);
922 _leave(" = %ld", PTR_ERR(key));
923 return PTR_ERR(key);
924 }
925
926 rx->securities = key;
927 kfree(description);
928 _leave(" = 0 [key %x]", key->serial);
929 return 0;
930}
931
932/*
933 * generate a server data key
934 */
935int rxrpc_get_server_data_key(struct rxrpc_connection *conn,
936 const void *session_key,
937 time_t expiry,
938 u32 kvno)
939{
940 const struct cred *cred = current_cred();
941 struct key *key;
942 int ret;
943
944 struct {
945 u32 kver;
946 struct rxrpc_key_data_v1 v1;
947 } data;
948
949 _enter("");
950
951 key = key_alloc(&key_type_rxrpc, "x",
952 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, 0,
953 KEY_ALLOC_NOT_IN_QUOTA);
954 if (IS_ERR(key)) {
955 _leave(" = -ENOMEM [alloc %ld]", PTR_ERR(key));
956 return -ENOMEM;
957 }
958
959 _debug("key %d", key_serial(key));
960
961 data.kver = 1;
962 data.v1.security_index = RXRPC_SECURITY_RXKAD;
963 data.v1.ticket_length = 0;
964 data.v1.expiry = expiry;
965 data.v1.kvno = 0;
966
967 memcpy(&data.v1.session_key, session_key, sizeof(data.v1.session_key));
968
969 ret = key_instantiate_and_link(key, &data, sizeof(data), NULL, NULL);
970 if (ret < 0)
971 goto error;
972
973 conn->key = key;
974 _leave(" = 0 [%d]", key_serial(key));
975 return 0;
976
977error:
978 key_revoke(key);
979 key_put(key);
980 _leave(" = -ENOMEM [ins %d]", ret);
981 return -ENOMEM;
982}
983EXPORT_SYMBOL(rxrpc_get_server_data_key);
984
985/**
986 * rxrpc_get_null_key - Generate a null RxRPC key
987 * @keyname: The name to give the key.
988 *
989 * Generate a null RxRPC key that can be used to indicate anonymous security is
990 * required for a particular domain.
991 */
992struct key *rxrpc_get_null_key(const char *keyname)
993{
994 const struct cred *cred = current_cred();
995 struct key *key;
996 int ret;
997
998 key = key_alloc(&key_type_rxrpc, keyname,
999 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
1000 KEY_POS_SEARCH, KEY_ALLOC_NOT_IN_QUOTA);
1001 if (IS_ERR(key))
1002 return key;
1003
1004 ret = key_instantiate_and_link(key, NULL, 0, NULL, NULL);
1005 if (ret < 0) {
1006 key_revoke(key);
1007 key_put(key);
1008 return ERR_PTR(ret);
1009 }
1010
1011 return key;
1012}
1013EXPORT_SYMBOL(rxrpc_get_null_key);
1014
1015/*
1016 * read the contents of an rxrpc key
1017 * - this returns the result in XDR form
1018 */
1019static long rxrpc_read(const struct key *key,
1020 char __user *buffer, size_t buflen)
1021{
1022 const struct rxrpc_key_token *token;
1023 const struct krb5_principal *princ;
1024 size_t size;
1025 __be32 __user *xdr, *oldxdr;
1026 u32 cnlen, toksize, ntoks, tok, zero;
1027 u16 toksizes[AFSTOKEN_MAX];
1028 int loop;
1029
1030 _enter("");
1031
1032 /* we don't know what form we should return non-AFS keys in */
1033 if (memcmp(key->description, "afs@", 4) != 0)
1034 return -EOPNOTSUPP;
1035 cnlen = strlen(key->description + 4);
1036
1037#define RND(X) (((X) + 3) & ~3)
1038
1039 /* AFS keys we return in XDR form, so we need to work out the size of
1040 * the XDR */
1041 size = 2 * 4; /* flags, cellname len */
1042 size += RND(cnlen); /* cellname */
1043 size += 1 * 4; /* token count */
1044
1045 ntoks = 0;
1046 for (token = key->payload.data; token; token = token->next) {
1047 toksize = 4; /* sec index */
1048
1049 switch (token->security_index) {
1050 case RXRPC_SECURITY_RXKAD:
1051 toksize += 8 * 4; /* viceid, kvno, key*2, begin,
1052 * end, primary, tktlen */
1053 toksize += RND(token->kad->ticket_len);
1054 break;
1055
1056 case RXRPC_SECURITY_RXK5:
1057 princ = &token->k5->client;
1058 toksize += 4 + princ->n_name_parts * 4;
1059 for (loop = 0; loop < princ->n_name_parts; loop++)
1060 toksize += RND(strlen(princ->name_parts[loop]));
1061 toksize += 4 + RND(strlen(princ->realm));
1062
1063 princ = &token->k5->server;
1064 toksize += 4 + princ->n_name_parts * 4;
1065 for (loop = 0; loop < princ->n_name_parts; loop++)
1066 toksize += RND(strlen(princ->name_parts[loop]));
1067 toksize += 4 + RND(strlen(princ->realm));
1068
1069 toksize += 8 + RND(token->k5->session.data_len);
1070
1071 toksize += 4 * 8 + 2 * 4;
1072
1073 toksize += 4 + token->k5->n_addresses * 8;
1074 for (loop = 0; loop < token->k5->n_addresses; loop++)
1075 toksize += RND(token->k5->addresses[loop].data_len);
1076
1077 toksize += 4 + RND(token->k5->ticket_len);
1078 toksize += 4 + RND(token->k5->ticket2_len);
1079
1080 toksize += 4 + token->k5->n_authdata * 8;
1081 for (loop = 0; loop < token->k5->n_authdata; loop++)
1082 toksize += RND(token->k5->authdata[loop].data_len);
1083 break;
1084
1085 default: /* we have a ticket we can't encode */
1086 BUG();
1087 continue;
1088 }
1089
1090 _debug("token[%u]: toksize=%u", ntoks, toksize);
1091 ASSERTCMP(toksize, <=, AFSTOKEN_LENGTH_MAX);
1092
1093 toksizes[ntoks++] = toksize;
1094 size += toksize + 4; /* each token has a length word */
1095 }
1096
1097#undef RND
1098
1099 if (!buffer || buflen < size)
1100 return size;
1101
1102 xdr = (__be32 __user *) buffer;
1103 zero = 0;
1104#define ENCODE(x) \
1105 do { \
1106 __be32 y = htonl(x); \
1107 if (put_user(y, xdr++) < 0) \
1108 goto fault; \
1109 } while(0)
1110#define ENCODE_DATA(l, s) \
1111 do { \
1112 u32 _l = (l); \
1113 ENCODE(l); \
1114 if (copy_to_user(xdr, (s), _l) != 0) \
1115 goto fault; \
1116 if (_l & 3 && \
1117 copy_to_user((u8 *)xdr + _l, &zero, 4 - (_l & 3)) != 0) \
1118 goto fault; \
1119 xdr += (_l + 3) >> 2; \
1120 } while(0)
1121#define ENCODE64(x) \
1122 do { \
1123 __be64 y = cpu_to_be64(x); \
1124 if (copy_to_user(xdr, &y, 8) != 0) \
1125 goto fault; \
1126 xdr += 8 >> 2; \
1127 } while(0)
1128#define ENCODE_STR(s) \
1129 do { \
1130 const char *_s = (s); \
1131 ENCODE_DATA(strlen(_s), _s); \
1132 } while(0)
1133
1134 ENCODE(0); /* flags */
1135 ENCODE_DATA(cnlen, key->description + 4); /* cellname */
1136 ENCODE(ntoks);
1137
1138 tok = 0;
1139 for (token = key->payload.data; token; token = token->next) {
1140 toksize = toksizes[tok++];
1141 ENCODE(toksize);
1142 oldxdr = xdr;
1143 ENCODE(token->security_index);
1144
1145 switch (token->security_index) {
1146 case RXRPC_SECURITY_RXKAD:
1147 ENCODE(token->kad->vice_id);
1148 ENCODE(token->kad->kvno);
1149 ENCODE_DATA(8, token->kad->session_key);
1150 ENCODE(token->kad->start);
1151 ENCODE(token->kad->expiry);
1152 ENCODE(token->kad->primary_flag);
1153 ENCODE_DATA(token->kad->ticket_len, token->kad->ticket);
1154 break;
1155
1156 case RXRPC_SECURITY_RXK5:
1157 princ = &token->k5->client;
1158 ENCODE(princ->n_name_parts);
1159 for (loop = 0; loop < princ->n_name_parts; loop++)
1160 ENCODE_STR(princ->name_parts[loop]);
1161 ENCODE_STR(princ->realm);
1162
1163 princ = &token->k5->server;
1164 ENCODE(princ->n_name_parts);
1165 for (loop = 0; loop < princ->n_name_parts; loop++)
1166 ENCODE_STR(princ->name_parts[loop]);
1167 ENCODE_STR(princ->realm);
1168
1169 ENCODE(token->k5->session.tag);
1170 ENCODE_DATA(token->k5->session.data_len,
1171 token->k5->session.data);
1172
1173 ENCODE64(token->k5->authtime);
1174 ENCODE64(token->k5->starttime);
1175 ENCODE64(token->k5->endtime);
1176 ENCODE64(token->k5->renew_till);
1177 ENCODE(token->k5->is_skey);
1178 ENCODE(token->k5->flags);
1179
1180 ENCODE(token->k5->n_addresses);
1181 for (loop = 0; loop < token->k5->n_addresses; loop++) {
1182 ENCODE(token->k5->addresses[loop].tag);
1183 ENCODE_DATA(token->k5->addresses[loop].data_len,
1184 token->k5->addresses[loop].data);
1185 }
1186
1187 ENCODE_DATA(token->k5->ticket_len, token->k5->ticket);
1188 ENCODE_DATA(token->k5->ticket2_len, token->k5->ticket2);
1189
1190 ENCODE(token->k5->n_authdata);
1191 for (loop = 0; loop < token->k5->n_authdata; loop++) {
1192 ENCODE(token->k5->authdata[loop].tag);
1193 ENCODE_DATA(token->k5->authdata[loop].data_len,
1194 token->k5->authdata[loop].data);
1195 }
1196 break;
1197
1198 default:
1199 BUG();
1200 break;
1201 }
1202
1203 ASSERTCMP((unsigned long)xdr - (unsigned long)oldxdr, ==,
1204 toksize);
1205 }
1206
1207#undef ENCODE_STR
1208#undef ENCODE_DATA
1209#undef ENCODE64
1210#undef ENCODE
1211
1212 ASSERTCMP(tok, ==, ntoks);
1213 ASSERTCMP((char __user *) xdr - buffer, ==, size);
1214 _leave(" = %zu", size);
1215 return size;
1216
1217fault:
1218 _leave(" = -EFAULT");
1219 return -EFAULT;
1220}
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#include <crypto/skcipher.h>
16#include <linux/module.h>
17#include <linux/net.h>
18#include <linux/skbuff.h>
19#include <linux/key-type.h>
20#include <linux/ctype.h>
21#include <linux/slab.h>
22#include <net/sock.h>
23#include <net/af_rxrpc.h>
24#include <keys/rxrpc-type.h>
25#include <keys/user-type.h>
26#include "ar-internal.h"
27
28static int rxrpc_vet_description_s(const char *);
29static int rxrpc_preparse(struct key_preparsed_payload *);
30static int rxrpc_preparse_s(struct key_preparsed_payload *);
31static void rxrpc_free_preparse(struct key_preparsed_payload *);
32static void rxrpc_free_preparse_s(struct key_preparsed_payload *);
33static void rxrpc_destroy(struct key *);
34static void rxrpc_destroy_s(struct key *);
35static void rxrpc_describe(const struct key *, struct seq_file *);
36static long rxrpc_read(const struct key *, char __user *, size_t);
37
38/*
39 * rxrpc defined keys take an arbitrary string as the description and an
40 * arbitrary blob of data as the payload
41 */
42struct key_type key_type_rxrpc = {
43 .name = "rxrpc",
44 .preparse = rxrpc_preparse,
45 .free_preparse = rxrpc_free_preparse,
46 .instantiate = generic_key_instantiate,
47 .destroy = rxrpc_destroy,
48 .describe = rxrpc_describe,
49 .read = rxrpc_read,
50};
51EXPORT_SYMBOL(key_type_rxrpc);
52
53/*
54 * rxrpc server defined keys take "<serviceId>:<securityIndex>" as the
55 * description and an 8-byte decryption key as the payload
56 */
57struct key_type key_type_rxrpc_s = {
58 .name = "rxrpc_s",
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 size_t plen;
94 u32 tktlen;
95
96 _enter(",{%x,%x,%x,%x},%u",
97 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
98 toklen);
99
100 if (toklen <= 8 * 4)
101 return -EKEYREJECTED;
102 tktlen = ntohl(xdr[7]);
103 _debug("tktlen: %x", tktlen);
104 if (tktlen > AFSTOKEN_RK_TIX_MAX)
105 return -EKEYREJECTED;
106 if (toklen < 8 * 4 + tktlen)
107 return -EKEYREJECTED;
108
109 plen = sizeof(*token) + sizeof(*token->kad) + tktlen;
110 prep->quotalen = datalen + plen;
111
112 plen -= sizeof(*token);
113 token = kzalloc(sizeof(*token), GFP_KERNEL);
114 if (!token)
115 return -ENOMEM;
116
117 token->kad = kzalloc(plen, GFP_KERNEL);
118 if (!token->kad) {
119 kfree(token);
120 return -ENOMEM;
121 }
122
123 token->security_index = RXRPC_SECURITY_RXKAD;
124 token->kad->ticket_len = tktlen;
125 token->kad->vice_id = ntohl(xdr[0]);
126 token->kad->kvno = ntohl(xdr[1]);
127 token->kad->start = ntohl(xdr[4]);
128 token->kad->expiry = ntohl(xdr[5]);
129 token->kad->primary_flag = ntohl(xdr[6]);
130 memcpy(&token->kad->session_key, &xdr[2], 8);
131 memcpy(&token->kad->ticket, &xdr[8], tktlen);
132
133 _debug("SCIX: %u", token->security_index);
134 _debug("TLEN: %u", token->kad->ticket_len);
135 _debug("EXPY: %x", token->kad->expiry);
136 _debug("KVNO: %u", token->kad->kvno);
137 _debug("PRIM: %u", token->kad->primary_flag);
138 _debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
139 token->kad->session_key[0], token->kad->session_key[1],
140 token->kad->session_key[2], token->kad->session_key[3],
141 token->kad->session_key[4], token->kad->session_key[5],
142 token->kad->session_key[6], token->kad->session_key[7]);
143 if (token->kad->ticket_len >= 8)
144 _debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
145 token->kad->ticket[0], token->kad->ticket[1],
146 token->kad->ticket[2], token->kad->ticket[3],
147 token->kad->ticket[4], token->kad->ticket[5],
148 token->kad->ticket[6], token->kad->ticket[7]);
149
150 /* count the number of tokens attached */
151 prep->payload.data[1] = (void *)((unsigned long)prep->payload.data[1] + 1);
152
153 /* attach the data */
154 for (pptoken = (struct rxrpc_key_token **)&prep->payload.data[0];
155 *pptoken;
156 pptoken = &(*pptoken)->next)
157 continue;
158 *pptoken = token;
159 if (token->kad->expiry < prep->expiry)
160 prep->expiry = token->kad->expiry;
161
162 _leave(" = 0");
163 return 0;
164}
165
166static void rxrpc_free_krb5_principal(struct krb5_principal *princ)
167{
168 int loop;
169
170 if (princ->name_parts) {
171 for (loop = princ->n_name_parts - 1; loop >= 0; loop--)
172 kfree(princ->name_parts[loop]);
173 kfree(princ->name_parts);
174 }
175 kfree(princ->realm);
176}
177
178static void rxrpc_free_krb5_tagged(struct krb5_tagged_data *td)
179{
180 kfree(td->data);
181}
182
183/*
184 * free up an RxK5 token
185 */
186static void rxrpc_rxk5_free(struct rxk5_key *rxk5)
187{
188 int loop;
189
190 rxrpc_free_krb5_principal(&rxk5->client);
191 rxrpc_free_krb5_principal(&rxk5->server);
192 rxrpc_free_krb5_tagged(&rxk5->session);
193
194 if (rxk5->addresses) {
195 for (loop = rxk5->n_addresses - 1; loop >= 0; loop--)
196 rxrpc_free_krb5_tagged(&rxk5->addresses[loop]);
197 kfree(rxk5->addresses);
198 }
199 if (rxk5->authdata) {
200 for (loop = rxk5->n_authdata - 1; loop >= 0; loop--)
201 rxrpc_free_krb5_tagged(&rxk5->authdata[loop]);
202 kfree(rxk5->authdata);
203 }
204
205 kfree(rxk5->ticket);
206 kfree(rxk5->ticket2);
207 kfree(rxk5);
208}
209
210/*
211 * extract a krb5 principal
212 */
213static int rxrpc_krb5_decode_principal(struct krb5_principal *princ,
214 const __be32 **_xdr,
215 unsigned int *_toklen)
216{
217 const __be32 *xdr = *_xdr;
218 unsigned int toklen = *_toklen, n_parts, loop, tmp;
219
220 /* there must be at least one name, and at least #names+1 length
221 * words */
222 if (toklen <= 12)
223 return -EINVAL;
224
225 _enter(",{%x,%x,%x},%u",
226 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), toklen);
227
228 n_parts = ntohl(*xdr++);
229 toklen -= 4;
230 if (n_parts <= 0 || n_parts > AFSTOKEN_K5_COMPONENTS_MAX)
231 return -EINVAL;
232 princ->n_name_parts = n_parts;
233
234 if (toklen <= (n_parts + 1) * 4)
235 return -EINVAL;
236
237 princ->name_parts = kcalloc(n_parts, sizeof(char *), GFP_KERNEL);
238 if (!princ->name_parts)
239 return -ENOMEM;
240
241 for (loop = 0; loop < n_parts; loop++) {
242 if (toklen < 4)
243 return -EINVAL;
244 tmp = ntohl(*xdr++);
245 toklen -= 4;
246 if (tmp <= 0 || tmp > AFSTOKEN_STRING_MAX)
247 return -EINVAL;
248 if (tmp > toklen)
249 return -EINVAL;
250 princ->name_parts[loop] = kmalloc(tmp + 1, GFP_KERNEL);
251 if (!princ->name_parts[loop])
252 return -ENOMEM;
253 memcpy(princ->name_parts[loop], xdr, tmp);
254 princ->name_parts[loop][tmp] = 0;
255 tmp = (tmp + 3) & ~3;
256 toklen -= tmp;
257 xdr += tmp >> 2;
258 }
259
260 if (toklen < 4)
261 return -EINVAL;
262 tmp = ntohl(*xdr++);
263 toklen -= 4;
264 if (tmp <= 0 || tmp > AFSTOKEN_K5_REALM_MAX)
265 return -EINVAL;
266 if (tmp > toklen)
267 return -EINVAL;
268 princ->realm = kmalloc(tmp + 1, GFP_KERNEL);
269 if (!princ->realm)
270 return -ENOMEM;
271 memcpy(princ->realm, xdr, tmp);
272 princ->realm[tmp] = 0;
273 tmp = (tmp + 3) & ~3;
274 toklen -= tmp;
275 xdr += tmp >> 2;
276
277 _debug("%s/...@%s", princ->name_parts[0], princ->realm);
278
279 *_xdr = xdr;
280 *_toklen = toklen;
281 _leave(" = 0 [toklen=%u]", toklen);
282 return 0;
283}
284
285/*
286 * extract a piece of krb5 tagged data
287 */
288static int rxrpc_krb5_decode_tagged_data(struct krb5_tagged_data *td,
289 size_t max_data_size,
290 const __be32 **_xdr,
291 unsigned int *_toklen)
292{
293 const __be32 *xdr = *_xdr;
294 unsigned int toklen = *_toklen, len;
295
296 /* there must be at least one tag and one length word */
297 if (toklen <= 8)
298 return -EINVAL;
299
300 _enter(",%zu,{%x,%x},%u",
301 max_data_size, ntohl(xdr[0]), ntohl(xdr[1]), toklen);
302
303 td->tag = ntohl(*xdr++);
304 len = ntohl(*xdr++);
305 toklen -= 8;
306 if (len > max_data_size)
307 return -EINVAL;
308 td->data_len = len;
309
310 if (len > 0) {
311 td->data = kmemdup(xdr, len, GFP_KERNEL);
312 if (!td->data)
313 return -ENOMEM;
314 len = (len + 3) & ~3;
315 toklen -= len;
316 xdr += len >> 2;
317 }
318
319 _debug("tag %x len %x", td->tag, td->data_len);
320
321 *_xdr = xdr;
322 *_toklen = toklen;
323 _leave(" = 0 [toklen=%u]", toklen);
324 return 0;
325}
326
327/*
328 * extract an array of tagged data
329 */
330static int rxrpc_krb5_decode_tagged_array(struct krb5_tagged_data **_td,
331 u8 *_n_elem,
332 u8 max_n_elem,
333 size_t max_elem_size,
334 const __be32 **_xdr,
335 unsigned int *_toklen)
336{
337 struct krb5_tagged_data *td;
338 const __be32 *xdr = *_xdr;
339 unsigned int toklen = *_toklen, n_elem, loop;
340 int ret;
341
342 /* there must be at least one count */
343 if (toklen < 4)
344 return -EINVAL;
345
346 _enter(",,%u,%zu,{%x},%u",
347 max_n_elem, max_elem_size, ntohl(xdr[0]), toklen);
348
349 n_elem = ntohl(*xdr++);
350 toklen -= 4;
351 if (n_elem > max_n_elem)
352 return -EINVAL;
353 *_n_elem = n_elem;
354 if (n_elem > 0) {
355 if (toklen <= (n_elem + 1) * 4)
356 return -EINVAL;
357
358 _debug("n_elem %d", n_elem);
359
360 td = kcalloc(n_elem, sizeof(struct krb5_tagged_data),
361 GFP_KERNEL);
362 if (!td)
363 return -ENOMEM;
364 *_td = td;
365
366 for (loop = 0; loop < n_elem; loop++) {
367 ret = rxrpc_krb5_decode_tagged_data(&td[loop],
368 max_elem_size,
369 &xdr, &toklen);
370 if (ret < 0)
371 return ret;
372 }
373 }
374
375 *_xdr = xdr;
376 *_toklen = toklen;
377 _leave(" = 0 [toklen=%u]", toklen);
378 return 0;
379}
380
381/*
382 * extract a krb5 ticket
383 */
384static int rxrpc_krb5_decode_ticket(u8 **_ticket, u16 *_tktlen,
385 const __be32 **_xdr, unsigned int *_toklen)
386{
387 const __be32 *xdr = *_xdr;
388 unsigned int toklen = *_toklen, len;
389
390 /* there must be at least one length word */
391 if (toklen <= 4)
392 return -EINVAL;
393
394 _enter(",{%x},%u", ntohl(xdr[0]), toklen);
395
396 len = ntohl(*xdr++);
397 toklen -= 4;
398 if (len > AFSTOKEN_K5_TIX_MAX)
399 return -EINVAL;
400 *_tktlen = len;
401
402 _debug("ticket len %u", len);
403
404 if (len > 0) {
405 *_ticket = kmemdup(xdr, len, GFP_KERNEL);
406 if (!*_ticket)
407 return -ENOMEM;
408 len = (len + 3) & ~3;
409 toklen -= len;
410 xdr += len >> 2;
411 }
412
413 *_xdr = xdr;
414 *_toklen = toklen;
415 _leave(" = 0 [toklen=%u]", toklen);
416 return 0;
417}
418
419/*
420 * parse an RxK5 type XDR format token
421 * - the caller guarantees we have at least 4 words
422 */
423static int rxrpc_preparse_xdr_rxk5(struct key_preparsed_payload *prep,
424 size_t datalen,
425 const __be32 *xdr, unsigned int toklen)
426{
427 struct rxrpc_key_token *token, **pptoken;
428 struct rxk5_key *rxk5;
429 const __be32 *end_xdr = xdr + (toklen >> 2);
430 int ret;
431
432 _enter(",{%x,%x,%x,%x},%u",
433 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
434 toklen);
435
436 /* reserve some payload space for this subkey - the length of the token
437 * is a reasonable approximation */
438 prep->quotalen = datalen + toklen;
439
440 token = kzalloc(sizeof(*token), GFP_KERNEL);
441 if (!token)
442 return -ENOMEM;
443
444 rxk5 = kzalloc(sizeof(*rxk5), GFP_KERNEL);
445 if (!rxk5) {
446 kfree(token);
447 return -ENOMEM;
448 }
449
450 token->security_index = RXRPC_SECURITY_RXK5;
451 token->k5 = rxk5;
452
453 /* extract the principals */
454 ret = rxrpc_krb5_decode_principal(&rxk5->client, &xdr, &toklen);
455 if (ret < 0)
456 goto error;
457 ret = rxrpc_krb5_decode_principal(&rxk5->server, &xdr, &toklen);
458 if (ret < 0)
459 goto error;
460
461 /* extract the session key and the encoding type (the tag field ->
462 * ENCTYPE_xxx) */
463 ret = rxrpc_krb5_decode_tagged_data(&rxk5->session, AFSTOKEN_DATA_MAX,
464 &xdr, &toklen);
465 if (ret < 0)
466 goto error;
467
468 if (toklen < 4 * 8 + 2 * 4)
469 goto inval;
470 rxk5->authtime = be64_to_cpup((const __be64 *) xdr);
471 xdr += 2;
472 rxk5->starttime = be64_to_cpup((const __be64 *) xdr);
473 xdr += 2;
474 rxk5->endtime = be64_to_cpup((const __be64 *) xdr);
475 xdr += 2;
476 rxk5->renew_till = be64_to_cpup((const __be64 *) xdr);
477 xdr += 2;
478 rxk5->is_skey = ntohl(*xdr++);
479 rxk5->flags = ntohl(*xdr++);
480 toklen -= 4 * 8 + 2 * 4;
481
482 _debug("times: a=%llx s=%llx e=%llx rt=%llx",
483 rxk5->authtime, rxk5->starttime, rxk5->endtime,
484 rxk5->renew_till);
485 _debug("is_skey=%x flags=%x", rxk5->is_skey, rxk5->flags);
486
487 /* extract the permitted client addresses */
488 ret = rxrpc_krb5_decode_tagged_array(&rxk5->addresses,
489 &rxk5->n_addresses,
490 AFSTOKEN_K5_ADDRESSES_MAX,
491 AFSTOKEN_DATA_MAX,
492 &xdr, &toklen);
493 if (ret < 0)
494 goto error;
495
496 ASSERTCMP((end_xdr - xdr) << 2, ==, toklen);
497
498 /* extract the tickets */
499 ret = rxrpc_krb5_decode_ticket(&rxk5->ticket, &rxk5->ticket_len,
500 &xdr, &toklen);
501 if (ret < 0)
502 goto error;
503 ret = rxrpc_krb5_decode_ticket(&rxk5->ticket2, &rxk5->ticket2_len,
504 &xdr, &toklen);
505 if (ret < 0)
506 goto error;
507
508 ASSERTCMP((end_xdr - xdr) << 2, ==, toklen);
509
510 /* extract the typed auth data */
511 ret = rxrpc_krb5_decode_tagged_array(&rxk5->authdata,
512 &rxk5->n_authdata,
513 AFSTOKEN_K5_AUTHDATA_MAX,
514 AFSTOKEN_BDATALN_MAX,
515 &xdr, &toklen);
516 if (ret < 0)
517 goto error;
518
519 ASSERTCMP((end_xdr - xdr) << 2, ==, toklen);
520
521 if (toklen != 0)
522 goto inval;
523
524 /* attach the payload */
525 for (pptoken = (struct rxrpc_key_token **)&prep->payload.data[0];
526 *pptoken;
527 pptoken = &(*pptoken)->next)
528 continue;
529 *pptoken = token;
530 if (token->kad->expiry < prep->expiry)
531 prep->expiry = token->kad->expiry;
532
533 _leave(" = 0");
534 return 0;
535
536inval:
537 ret = -EINVAL;
538error:
539 rxrpc_rxk5_free(rxk5);
540 kfree(token);
541 _leave(" = %d", ret);
542 return ret;
543}
544
545/*
546 * attempt to parse the data as the XDR format
547 * - the caller guarantees we have more than 7 words
548 */
549static int rxrpc_preparse_xdr(struct key_preparsed_payload *prep)
550{
551 const __be32 *xdr = prep->data, *token;
552 const char *cp;
553 unsigned int len, tmp, loop, ntoken, toklen, sec_ix;
554 size_t datalen = prep->datalen;
555 int ret;
556
557 _enter(",{%x,%x,%x,%x},%zu",
558 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
559 prep->datalen);
560
561 if (datalen > AFSTOKEN_LENGTH_MAX)
562 goto not_xdr;
563
564 /* XDR is an array of __be32's */
565 if (datalen & 3)
566 goto not_xdr;
567
568 /* the flags should be 0 (the setpag bit must be handled by
569 * userspace) */
570 if (ntohl(*xdr++) != 0)
571 goto not_xdr;
572 datalen -= 4;
573
574 /* check the cell name */
575 len = ntohl(*xdr++);
576 if (len < 1 || len > AFSTOKEN_CELL_MAX)
577 goto not_xdr;
578 datalen -= 4;
579 tmp = (len + 3) & ~3;
580 if (tmp > datalen)
581 goto not_xdr;
582
583 cp = (const char *) xdr;
584 for (loop = 0; loop < len; loop++)
585 if (!isprint(cp[loop]))
586 goto not_xdr;
587 if (len < tmp)
588 for (; loop < tmp; loop++)
589 if (cp[loop])
590 goto not_xdr;
591 _debug("cellname: [%u/%u] '%*.*s'",
592 len, tmp, len, len, (const char *) xdr);
593 datalen -= tmp;
594 xdr += tmp >> 2;
595
596 /* get the token count */
597 if (datalen < 12)
598 goto not_xdr;
599 ntoken = ntohl(*xdr++);
600 datalen -= 4;
601 _debug("ntoken: %x", ntoken);
602 if (ntoken < 1 || ntoken > AFSTOKEN_MAX)
603 goto not_xdr;
604
605 /* check each token wrapper */
606 token = xdr;
607 loop = ntoken;
608 do {
609 if (datalen < 8)
610 goto not_xdr;
611 toklen = ntohl(*xdr++);
612 sec_ix = ntohl(*xdr);
613 datalen -= 4;
614 _debug("token: [%x/%zx] %x", toklen, datalen, sec_ix);
615 if (toklen < 20 || toklen > datalen)
616 goto not_xdr;
617 datalen -= (toklen + 3) & ~3;
618 xdr += (toklen + 3) >> 2;
619
620 } while (--loop > 0);
621
622 _debug("remainder: %zu", datalen);
623 if (datalen != 0)
624 goto not_xdr;
625
626 /* okay: we're going to assume it's valid XDR format
627 * - we ignore the cellname, relying on the key to be correctly named
628 */
629 do {
630 xdr = token;
631 toklen = ntohl(*xdr++);
632 token = xdr + ((toklen + 3) >> 2);
633 sec_ix = ntohl(*xdr++);
634 toklen -= 4;
635
636 _debug("TOKEN type=%u [%p-%p]", sec_ix, xdr, token);
637
638 switch (sec_ix) {
639 case RXRPC_SECURITY_RXKAD:
640 ret = rxrpc_preparse_xdr_rxkad(prep, datalen, xdr, toklen);
641 if (ret != 0)
642 goto error;
643 break;
644
645 case RXRPC_SECURITY_RXK5:
646 ret = rxrpc_preparse_xdr_rxk5(prep, datalen, xdr, toklen);
647 if (ret != 0)
648 goto error;
649 break;
650
651 default:
652 ret = -EPROTONOSUPPORT;
653 goto error;
654 }
655
656 } while (--ntoken > 0);
657
658 _leave(" = 0");
659 return 0;
660
661not_xdr:
662 _leave(" = -EPROTO");
663 return -EPROTO;
664error:
665 _leave(" = %d", ret);
666 return ret;
667}
668
669/*
670 * Preparse an rxrpc defined key.
671 *
672 * Data should be of the form:
673 * OFFSET LEN CONTENT
674 * 0 4 key interface version number
675 * 4 2 security index (type)
676 * 6 2 ticket length
677 * 8 4 key expiry time (time_t)
678 * 12 4 kvno
679 * 16 8 session key
680 * 24 [len] ticket
681 *
682 * if no data is provided, then a no-security key is made
683 */
684static int rxrpc_preparse(struct key_preparsed_payload *prep)
685{
686 const struct rxrpc_key_data_v1 *v1;
687 struct rxrpc_key_token *token, **pp;
688 size_t plen;
689 u32 kver;
690 int ret;
691
692 _enter("%zu", prep->datalen);
693
694 /* handle a no-security key */
695 if (!prep->data && prep->datalen == 0)
696 return 0;
697
698 /* determine if the XDR payload format is being used */
699 if (prep->datalen > 7 * 4) {
700 ret = rxrpc_preparse_xdr(prep);
701 if (ret != -EPROTO)
702 return ret;
703 }
704
705 /* get the key interface version number */
706 ret = -EINVAL;
707 if (prep->datalen <= 4 || !prep->data)
708 goto error;
709 memcpy(&kver, prep->data, sizeof(kver));
710 prep->data += sizeof(kver);
711 prep->datalen -= sizeof(kver);
712
713 _debug("KEY I/F VERSION: %u", kver);
714
715 ret = -EKEYREJECTED;
716 if (kver != 1)
717 goto error;
718
719 /* deal with a version 1 key */
720 ret = -EINVAL;
721 if (prep->datalen < sizeof(*v1))
722 goto error;
723
724 v1 = prep->data;
725 if (prep->datalen != sizeof(*v1) + v1->ticket_length)
726 goto error;
727
728 _debug("SCIX: %u", v1->security_index);
729 _debug("TLEN: %u", v1->ticket_length);
730 _debug("EXPY: %x", v1->expiry);
731 _debug("KVNO: %u", v1->kvno);
732 _debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
733 v1->session_key[0], v1->session_key[1],
734 v1->session_key[2], v1->session_key[3],
735 v1->session_key[4], v1->session_key[5],
736 v1->session_key[6], v1->session_key[7]);
737 if (v1->ticket_length >= 8)
738 _debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
739 v1->ticket[0], v1->ticket[1],
740 v1->ticket[2], v1->ticket[3],
741 v1->ticket[4], v1->ticket[5],
742 v1->ticket[6], v1->ticket[7]);
743
744 ret = -EPROTONOSUPPORT;
745 if (v1->security_index != RXRPC_SECURITY_RXKAD)
746 goto error;
747
748 plen = sizeof(*token->kad) + v1->ticket_length;
749 prep->quotalen = plen + sizeof(*token);
750
751 ret = -ENOMEM;
752 token = kzalloc(sizeof(*token), GFP_KERNEL);
753 if (!token)
754 goto error;
755 token->kad = kzalloc(plen, GFP_KERNEL);
756 if (!token->kad)
757 goto error_free;
758
759 token->security_index = RXRPC_SECURITY_RXKAD;
760 token->kad->ticket_len = v1->ticket_length;
761 token->kad->expiry = v1->expiry;
762 token->kad->kvno = v1->kvno;
763 memcpy(&token->kad->session_key, &v1->session_key, 8);
764 memcpy(&token->kad->ticket, v1->ticket, v1->ticket_length);
765
766 /* count the number of tokens attached */
767 prep->payload.data[1] = (void *)((unsigned long)prep->payload.data[1] + 1);
768
769 /* attach the data */
770 pp = (struct rxrpc_key_token **)&prep->payload.data[0];
771 while (*pp)
772 pp = &(*pp)->next;
773 *pp = token;
774 if (token->kad->expiry < prep->expiry)
775 prep->expiry = token->kad->expiry;
776 token = NULL;
777 ret = 0;
778
779error_free:
780 kfree(token);
781error:
782 return ret;
783}
784
785/*
786 * Free token list.
787 */
788static void rxrpc_free_token_list(struct rxrpc_key_token *token)
789{
790 struct rxrpc_key_token *next;
791
792 for (; token; token = next) {
793 next = token->next;
794 switch (token->security_index) {
795 case RXRPC_SECURITY_RXKAD:
796 kfree(token->kad);
797 break;
798 case RXRPC_SECURITY_RXK5:
799 if (token->k5)
800 rxrpc_rxk5_free(token->k5);
801 break;
802 default:
803 printk(KERN_ERR "Unknown token type %x on rxrpc key\n",
804 token->security_index);
805 BUG();
806 }
807
808 kfree(token);
809 }
810}
811
812/*
813 * Clean up preparse data.
814 */
815static void rxrpc_free_preparse(struct key_preparsed_payload *prep)
816{
817 rxrpc_free_token_list(prep->payload.data[0]);
818}
819
820/*
821 * Preparse a server secret key.
822 *
823 * The data should be the 8-byte secret key.
824 */
825static int rxrpc_preparse_s(struct key_preparsed_payload *prep)
826{
827 struct crypto_skcipher *ci;
828
829 _enter("%zu", prep->datalen);
830
831 if (prep->datalen != 8)
832 return -EINVAL;
833
834 memcpy(&prep->payload.data[2], prep->data, 8);
835
836 ci = crypto_alloc_skcipher("pcbc(des)", 0, CRYPTO_ALG_ASYNC);
837 if (IS_ERR(ci)) {
838 _leave(" = %ld", PTR_ERR(ci));
839 return PTR_ERR(ci);
840 }
841
842 if (crypto_skcipher_setkey(ci, prep->data, 8) < 0)
843 BUG();
844
845 prep->payload.data[0] = ci;
846 _leave(" = 0");
847 return 0;
848}
849
850/*
851 * Clean up preparse data.
852 */
853static void rxrpc_free_preparse_s(struct key_preparsed_payload *prep)
854{
855 if (prep->payload.data[0])
856 crypto_free_skcipher(prep->payload.data[0]);
857}
858
859/*
860 * dispose of the data dangling from the corpse of a rxrpc key
861 */
862static void rxrpc_destroy(struct key *key)
863{
864 rxrpc_free_token_list(key->payload.data[0]);
865}
866
867/*
868 * dispose of the data dangling from the corpse of a rxrpc key
869 */
870static void rxrpc_destroy_s(struct key *key)
871{
872 if (key->payload.data[0]) {
873 crypto_free_skcipher(key->payload.data[0]);
874 key->payload.data[0] = NULL;
875 }
876}
877
878/*
879 * describe the rxrpc key
880 */
881static void rxrpc_describe(const struct key *key, struct seq_file *m)
882{
883 seq_puts(m, key->description);
884}
885
886/*
887 * grab the security key for a socket
888 */
889int rxrpc_request_key(struct rxrpc_sock *rx, char __user *optval, int optlen)
890{
891 struct key *key;
892 char *description;
893
894 _enter("");
895
896 if (optlen <= 0 || optlen > PAGE_SIZE - 1)
897 return -EINVAL;
898
899 description = memdup_user_nul(optval, optlen);
900 if (IS_ERR(description))
901 return PTR_ERR(description);
902
903 key = request_key(&key_type_rxrpc, description, NULL);
904 if (IS_ERR(key)) {
905 kfree(description);
906 _leave(" = %ld", PTR_ERR(key));
907 return PTR_ERR(key);
908 }
909
910 rx->key = key;
911 kfree(description);
912 _leave(" = 0 [key %x]", key->serial);
913 return 0;
914}
915
916/*
917 * grab the security keyring for a server socket
918 */
919int rxrpc_server_keyring(struct rxrpc_sock *rx, char __user *optval,
920 int optlen)
921{
922 struct key *key;
923 char *description;
924
925 _enter("");
926
927 if (optlen <= 0 || optlen > PAGE_SIZE - 1)
928 return -EINVAL;
929
930 description = memdup_user_nul(optval, optlen);
931 if (IS_ERR(description))
932 return PTR_ERR(description);
933
934 key = request_key(&key_type_keyring, description, NULL);
935 if (IS_ERR(key)) {
936 kfree(description);
937 _leave(" = %ld", PTR_ERR(key));
938 return PTR_ERR(key);
939 }
940
941 rx->securities = key;
942 kfree(description);
943 _leave(" = 0 [key %x]", key->serial);
944 return 0;
945}
946
947/*
948 * generate a server data key
949 */
950int rxrpc_get_server_data_key(struct rxrpc_connection *conn,
951 const void *session_key,
952 time_t expiry,
953 u32 kvno)
954{
955 const struct cred *cred = current_cred();
956 struct key *key;
957 int ret;
958
959 struct {
960 u32 kver;
961 struct rxrpc_key_data_v1 v1;
962 } data;
963
964 _enter("");
965
966 key = key_alloc(&key_type_rxrpc, "x",
967 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, 0,
968 KEY_ALLOC_NOT_IN_QUOTA);
969 if (IS_ERR(key)) {
970 _leave(" = -ENOMEM [alloc %ld]", PTR_ERR(key));
971 return -ENOMEM;
972 }
973
974 _debug("key %d", key_serial(key));
975
976 data.kver = 1;
977 data.v1.security_index = RXRPC_SECURITY_RXKAD;
978 data.v1.ticket_length = 0;
979 data.v1.expiry = expiry;
980 data.v1.kvno = 0;
981
982 memcpy(&data.v1.session_key, session_key, sizeof(data.v1.session_key));
983
984 ret = key_instantiate_and_link(key, &data, sizeof(data), NULL, NULL);
985 if (ret < 0)
986 goto error;
987
988 conn->key = key;
989 _leave(" = 0 [%d]", key_serial(key));
990 return 0;
991
992error:
993 key_revoke(key);
994 key_put(key);
995 _leave(" = -ENOMEM [ins %d]", ret);
996 return -ENOMEM;
997}
998EXPORT_SYMBOL(rxrpc_get_server_data_key);
999
1000/**
1001 * rxrpc_get_null_key - Generate a null RxRPC key
1002 * @keyname: The name to give the key.
1003 *
1004 * Generate a null RxRPC key that can be used to indicate anonymous security is
1005 * required for a particular domain.
1006 */
1007struct key *rxrpc_get_null_key(const char *keyname)
1008{
1009 const struct cred *cred = current_cred();
1010 struct key *key;
1011 int ret;
1012
1013 key = key_alloc(&key_type_rxrpc, keyname,
1014 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
1015 KEY_POS_SEARCH, KEY_ALLOC_NOT_IN_QUOTA);
1016 if (IS_ERR(key))
1017 return key;
1018
1019 ret = key_instantiate_and_link(key, NULL, 0, NULL, NULL);
1020 if (ret < 0) {
1021 key_revoke(key);
1022 key_put(key);
1023 return ERR_PTR(ret);
1024 }
1025
1026 return key;
1027}
1028EXPORT_SYMBOL(rxrpc_get_null_key);
1029
1030/*
1031 * read the contents of an rxrpc key
1032 * - this returns the result in XDR form
1033 */
1034static long rxrpc_read(const struct key *key,
1035 char __user *buffer, size_t buflen)
1036{
1037 const struct rxrpc_key_token *token;
1038 const struct krb5_principal *princ;
1039 size_t size;
1040 __be32 __user *xdr, *oldxdr;
1041 u32 cnlen, toksize, ntoks, tok, zero;
1042 u16 toksizes[AFSTOKEN_MAX];
1043 int loop;
1044
1045 _enter("");
1046
1047 /* we don't know what form we should return non-AFS keys in */
1048 if (memcmp(key->description, "afs@", 4) != 0)
1049 return -EOPNOTSUPP;
1050 cnlen = strlen(key->description + 4);
1051
1052#define RND(X) (((X) + 3) & ~3)
1053
1054 /* AFS keys we return in XDR form, so we need to work out the size of
1055 * the XDR */
1056 size = 2 * 4; /* flags, cellname len */
1057 size += RND(cnlen); /* cellname */
1058 size += 1 * 4; /* token count */
1059
1060 ntoks = 0;
1061 for (token = key->payload.data[0]; token; token = token->next) {
1062 toksize = 4; /* sec index */
1063
1064 switch (token->security_index) {
1065 case RXRPC_SECURITY_RXKAD:
1066 toksize += 8 * 4; /* viceid, kvno, key*2, begin,
1067 * end, primary, tktlen */
1068 toksize += RND(token->kad->ticket_len);
1069 break;
1070
1071 case RXRPC_SECURITY_RXK5:
1072 princ = &token->k5->client;
1073 toksize += 4 + princ->n_name_parts * 4;
1074 for (loop = 0; loop < princ->n_name_parts; loop++)
1075 toksize += RND(strlen(princ->name_parts[loop]));
1076 toksize += 4 + RND(strlen(princ->realm));
1077
1078 princ = &token->k5->server;
1079 toksize += 4 + princ->n_name_parts * 4;
1080 for (loop = 0; loop < princ->n_name_parts; loop++)
1081 toksize += RND(strlen(princ->name_parts[loop]));
1082 toksize += 4 + RND(strlen(princ->realm));
1083
1084 toksize += 8 + RND(token->k5->session.data_len);
1085
1086 toksize += 4 * 8 + 2 * 4;
1087
1088 toksize += 4 + token->k5->n_addresses * 8;
1089 for (loop = 0; loop < token->k5->n_addresses; loop++)
1090 toksize += RND(token->k5->addresses[loop].data_len);
1091
1092 toksize += 4 + RND(token->k5->ticket_len);
1093 toksize += 4 + RND(token->k5->ticket2_len);
1094
1095 toksize += 4 + token->k5->n_authdata * 8;
1096 for (loop = 0; loop < token->k5->n_authdata; loop++)
1097 toksize += RND(token->k5->authdata[loop].data_len);
1098 break;
1099
1100 default: /* we have a ticket we can't encode */
1101 BUG();
1102 continue;
1103 }
1104
1105 _debug("token[%u]: toksize=%u", ntoks, toksize);
1106 ASSERTCMP(toksize, <=, AFSTOKEN_LENGTH_MAX);
1107
1108 toksizes[ntoks++] = toksize;
1109 size += toksize + 4; /* each token has a length word */
1110 }
1111
1112#undef RND
1113
1114 if (!buffer || buflen < size)
1115 return size;
1116
1117 xdr = (__be32 __user *) buffer;
1118 zero = 0;
1119#define ENCODE(x) \
1120 do { \
1121 __be32 y = htonl(x); \
1122 if (put_user(y, xdr++) < 0) \
1123 goto fault; \
1124 } while(0)
1125#define ENCODE_DATA(l, s) \
1126 do { \
1127 u32 _l = (l); \
1128 ENCODE(l); \
1129 if (copy_to_user(xdr, (s), _l) != 0) \
1130 goto fault; \
1131 if (_l & 3 && \
1132 copy_to_user((u8 __user *)xdr + _l, &zero, 4 - (_l & 3)) != 0) \
1133 goto fault; \
1134 xdr += (_l + 3) >> 2; \
1135 } while(0)
1136#define ENCODE64(x) \
1137 do { \
1138 __be64 y = cpu_to_be64(x); \
1139 if (copy_to_user(xdr, &y, 8) != 0) \
1140 goto fault; \
1141 xdr += 8 >> 2; \
1142 } while(0)
1143#define ENCODE_STR(s) \
1144 do { \
1145 const char *_s = (s); \
1146 ENCODE_DATA(strlen(_s), _s); \
1147 } while(0)
1148
1149 ENCODE(0); /* flags */
1150 ENCODE_DATA(cnlen, key->description + 4); /* cellname */
1151 ENCODE(ntoks);
1152
1153 tok = 0;
1154 for (token = key->payload.data[0]; token; token = token->next) {
1155 toksize = toksizes[tok++];
1156 ENCODE(toksize);
1157 oldxdr = xdr;
1158 ENCODE(token->security_index);
1159
1160 switch (token->security_index) {
1161 case RXRPC_SECURITY_RXKAD:
1162 ENCODE(token->kad->vice_id);
1163 ENCODE(token->kad->kvno);
1164 ENCODE_DATA(8, token->kad->session_key);
1165 ENCODE(token->kad->start);
1166 ENCODE(token->kad->expiry);
1167 ENCODE(token->kad->primary_flag);
1168 ENCODE_DATA(token->kad->ticket_len, token->kad->ticket);
1169 break;
1170
1171 case RXRPC_SECURITY_RXK5:
1172 princ = &token->k5->client;
1173 ENCODE(princ->n_name_parts);
1174 for (loop = 0; loop < princ->n_name_parts; loop++)
1175 ENCODE_STR(princ->name_parts[loop]);
1176 ENCODE_STR(princ->realm);
1177
1178 princ = &token->k5->server;
1179 ENCODE(princ->n_name_parts);
1180 for (loop = 0; loop < princ->n_name_parts; loop++)
1181 ENCODE_STR(princ->name_parts[loop]);
1182 ENCODE_STR(princ->realm);
1183
1184 ENCODE(token->k5->session.tag);
1185 ENCODE_DATA(token->k5->session.data_len,
1186 token->k5->session.data);
1187
1188 ENCODE64(token->k5->authtime);
1189 ENCODE64(token->k5->starttime);
1190 ENCODE64(token->k5->endtime);
1191 ENCODE64(token->k5->renew_till);
1192 ENCODE(token->k5->is_skey);
1193 ENCODE(token->k5->flags);
1194
1195 ENCODE(token->k5->n_addresses);
1196 for (loop = 0; loop < token->k5->n_addresses; loop++) {
1197 ENCODE(token->k5->addresses[loop].tag);
1198 ENCODE_DATA(token->k5->addresses[loop].data_len,
1199 token->k5->addresses[loop].data);
1200 }
1201
1202 ENCODE_DATA(token->k5->ticket_len, token->k5->ticket);
1203 ENCODE_DATA(token->k5->ticket2_len, token->k5->ticket2);
1204
1205 ENCODE(token->k5->n_authdata);
1206 for (loop = 0; loop < token->k5->n_authdata; loop++) {
1207 ENCODE(token->k5->authdata[loop].tag);
1208 ENCODE_DATA(token->k5->authdata[loop].data_len,
1209 token->k5->authdata[loop].data);
1210 }
1211 break;
1212
1213 default:
1214 BUG();
1215 break;
1216 }
1217
1218 ASSERTCMP((unsigned long)xdr - (unsigned long)oldxdr, ==,
1219 toksize);
1220 }
1221
1222#undef ENCODE_STR
1223#undef ENCODE_DATA
1224#undef ENCODE64
1225#undef ENCODE
1226
1227 ASSERTCMP(tok, ==, ntoks);
1228 ASSERTCMP((char __user *) xdr - buffer, ==, size);
1229 _leave(" = %zu", size);
1230 return size;
1231
1232fault:
1233 _leave(" = -EFAULT");
1234 return -EFAULT;
1235}