]> git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blob - net/rxrpc/key.c
projects / mirror_ubuntu-artful-kernel.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
KVM: SVM: Move spec control call after restore of GS
[mirror_ubuntu-artful-kernel.git] / net / rxrpc / key.c
1 /* RxRPC key management
2 *
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 *
11 * RxRPC keys should have a description of describing their purpose:
12 * "afs@CAMBRIDGE.REDHAT.COM>
13 */
14
15 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16
17 #include <crypto/skcipher.h>
18 #include <linux/module.h>
19 #include <linux/net.h>
20 #include <linux/skbuff.h>
21 #include <linux/key-type.h>
22 #include <linux/ctype.h>
23 #include <linux/slab.h>
24 #include <net/sock.h>
25 #include <net/af_rxrpc.h>
26 #include <keys/rxrpc-type.h>
27 #include <keys/user-type.h>
28 #include "ar-internal.h"
29
30 static int rxrpc_vet_description_s(const char *);
31 static int rxrpc_preparse(struct key_preparsed_payload *);
32 static int rxrpc_preparse_s(struct key_preparsed_payload *);
33 static void rxrpc_free_preparse(struct key_preparsed_payload *);
34 static void rxrpc_free_preparse_s(struct key_preparsed_payload *);
35 static void rxrpc_destroy(struct key *);
36 static void rxrpc_destroy_s(struct key *);
37 static void rxrpc_describe(const struct key *, struct seq_file *);
38 static long rxrpc_read(const struct key *, char __user *, size_t);
39
40 /*
41 * rxrpc defined keys take an arbitrary string as the description and an
42 * arbitrary blob of data as the payload
43 */
44 struct key_type key_type_rxrpc = {
45 .name = "rxrpc",
46 .preparse = rxrpc_preparse,
47 .free_preparse = rxrpc_free_preparse,
48 .instantiate = generic_key_instantiate,
49 .destroy = rxrpc_destroy,
50 .describe = rxrpc_describe,
51 .read = rxrpc_read,
52 };
53 EXPORT_SYMBOL(key_type_rxrpc);
54
55 /*
56 * rxrpc server defined keys take "<serviceId>:<securityIndex>" as the
57 * description and an 8-byte decryption key as the payload
58 */
59 struct key_type key_type_rxrpc_s = {
60 .name = "rxrpc_s",
61 .vet_description = rxrpc_vet_description_s,
62 .preparse = rxrpc_preparse_s,
63 .free_preparse = rxrpc_free_preparse_s,
64 .instantiate = generic_key_instantiate,
65 .destroy = rxrpc_destroy_s,
66 .describe = rxrpc_describe,
67 };
68
69 /*
70 * Vet the description for an RxRPC server key
71 */
72 static int rxrpc_vet_description_s(const char *desc)
73 {
74 unsigned long num;
75 char *p;
76
77 num = simple_strtoul(desc, &p, 10);
78 if (*p != ':' || num > 65535)
79 return -EINVAL;
80 num = simple_strtoul(p + 1, &p, 10);
81 if (*p || num < 1 || num > 255)
82 return -EINVAL;
83 return 0;
84 }
85
86 /*
87 * parse an RxKAD type XDR format token
88 * - the caller guarantees we have at least 4 words
89 */
90 static int rxrpc_preparse_xdr_rxkad(struct key_preparsed_payload *prep,
91 size_t datalen,
92 const __be32 *xdr, unsigned int toklen)
93 {
94 struct rxrpc_key_token *token, **pptoken;
95 size_t plen;
96 u32 tktlen;
97
98 _enter(",{%x,%x,%x,%x},%u",
99 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
100 toklen);
101
102 if (toklen <= 8 * 4)
103 return -EKEYREJECTED;
104 tktlen = ntohl(xdr[7]);
105 _debug("tktlen: %x", tktlen);
106 if (tktlen > AFSTOKEN_RK_TIX_MAX)
107 return -EKEYREJECTED;
108 if (toklen < 8 * 4 + tktlen)
109 return -EKEYREJECTED;
110
111 plen = sizeof(*token) + sizeof(*token->kad) + tktlen;
112 prep->quotalen = datalen + plen;
113
114 plen -= sizeof(*token);
115 token = kzalloc(sizeof(*token), GFP_KERNEL);
116 if (!token)
117 return -ENOMEM;
118
119 token->kad = kzalloc(plen, GFP_KERNEL);
120 if (!token->kad) {
121 kfree(token);
122 return -ENOMEM;
123 }
124
125 token->security_index = RXRPC_SECURITY_RXKAD;
126 token->kad->ticket_len = tktlen;
127 token->kad->vice_id = ntohl(xdr[0]);
128 token->kad->kvno = ntohl(xdr[1]);
129 token->kad->start = ntohl(xdr[4]);
130 token->kad->expiry = ntohl(xdr[5]);
131 token->kad->primary_flag = ntohl(xdr[6]);
132 memcpy(&token->kad->session_key, &xdr[2], 8);
133 memcpy(&token->kad->ticket, &xdr[8], tktlen);
134
135 _debug("SCIX: %u", token->security_index);
136 _debug("TLEN: %u", token->kad->ticket_len);
137 _debug("EXPY: %x", token->kad->expiry);
138 _debug("KVNO: %u", token->kad->kvno);
139 _debug("PRIM: %u", token->kad->primary_flag);
140 _debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
141 token->kad->session_key[0], token->kad->session_key[1],
142 token->kad->session_key[2], token->kad->session_key[3],
143 token->kad->session_key[4], token->kad->session_key[5],
144 token->kad->session_key[6], token->kad->session_key[7]);
145 if (token->kad->ticket_len >= 8)
146 _debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
147 token->kad->ticket[0], token->kad->ticket[1],
148 token->kad->ticket[2], token->kad->ticket[3],
149 token->kad->ticket[4], token->kad->ticket[5],
150 token->kad->ticket[6], token->kad->ticket[7]);
151
152 /* count the number of tokens attached */
153 prep->payload.data[1] = (void *)((unsigned long)prep->payload.data[1] + 1);
154
155 /* attach the data */
156 for (pptoken = (struct rxrpc_key_token **)&prep->payload.data[0];
157 *pptoken;
158 pptoken = &(*pptoken)->next)
159 continue;
160 *pptoken = token;
161 if (token->kad->expiry < prep->expiry)
162 prep->expiry = token->kad->expiry;
163
164 _leave(" = 0");
165 return 0;
166 }
167
168 static 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
180 static 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 */
188 static 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 */
215 static 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 */
290 static 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 */
334 static 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 */
388 static 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 */
429 static 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 int ret;
437
438 _enter(",{%x,%x,%x,%x},%u",
439 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
440 toklen);
441
442 /* reserve some payload space for this subkey - the length of the token
443 * is a reasonable approximation */
444 prep->quotalen = datalen + toklen;
445
446 token = kzalloc(sizeof(*token), GFP_KERNEL);
447 if (!token)
448 return -ENOMEM;
449
450 rxk5 = kzalloc(sizeof(*rxk5), GFP_KERNEL);
451 if (!rxk5) {
452 kfree(token);
453 return -ENOMEM;
454 }
455
456 token->security_index = RXRPC_SECURITY_RXK5;
457 token->k5 = rxk5;
458
459 /* extract the principals */
460 ret = rxrpc_krb5_decode_principal(&rxk5->client, &xdr, &toklen);
461 if (ret < 0)
462 goto error;
463 ret = rxrpc_krb5_decode_principal(&rxk5->server, &xdr, &toklen);
464 if (ret < 0)
465 goto error;
466
467 /* extract the session key and the encoding type (the tag field ->
468 * ENCTYPE_xxx) */
469 ret = rxrpc_krb5_decode_tagged_data(&rxk5->session, AFSTOKEN_DATA_MAX,
470 &xdr, &toklen);
471 if (ret < 0)
472 goto error;
473
474 if (toklen < 4 * 8 + 2 * 4)
475 goto inval;
476 rxk5->authtime = be64_to_cpup((const __be64 *) xdr);
477 xdr += 2;
478 rxk5->starttime = be64_to_cpup((const __be64 *) xdr);
479 xdr += 2;
480 rxk5->endtime = be64_to_cpup((const __be64 *) xdr);
481 xdr += 2;
482 rxk5->renew_till = be64_to_cpup((const __be64 *) xdr);
483 xdr += 2;
484 rxk5->is_skey = ntohl(*xdr++);
485 rxk5->flags = ntohl(*xdr++);
486 toklen -= 4 * 8 + 2 * 4;
487
488 _debug("times: a=%llx s=%llx e=%llx rt=%llx",
489 rxk5->authtime, rxk5->starttime, rxk5->endtime,
490 rxk5->renew_till);
491 _debug("is_skey=%x flags=%x", rxk5->is_skey, rxk5->flags);
492
493 /* extract the permitted client addresses */
494 ret = rxrpc_krb5_decode_tagged_array(&rxk5->addresses,
495 &rxk5->n_addresses,
496 AFSTOKEN_K5_ADDRESSES_MAX,
497 AFSTOKEN_DATA_MAX,
498 &xdr, &toklen);
499 if (ret < 0)
500 goto error;
501
502 ASSERTCMP((end_xdr - xdr) << 2, ==, toklen);
503
504 /* extract the tickets */
505 ret = rxrpc_krb5_decode_ticket(&rxk5->ticket, &rxk5->ticket_len,
506 &xdr, &toklen);
507 if (ret < 0)
508 goto error;
509 ret = rxrpc_krb5_decode_ticket(&rxk5->ticket2, &rxk5->ticket2_len,
510 &xdr, &toklen);
511 if (ret < 0)
512 goto error;
513
514 ASSERTCMP((end_xdr - xdr) << 2, ==, toklen);
515
516 /* extract the typed auth data */
517 ret = rxrpc_krb5_decode_tagged_array(&rxk5->authdata,
518 &rxk5->n_authdata,
519 AFSTOKEN_K5_AUTHDATA_MAX,
520 AFSTOKEN_BDATALN_MAX,
521 &xdr, &toklen);
522 if (ret < 0)
523 goto error;
524
525 ASSERTCMP((end_xdr - xdr) << 2, ==, toklen);
526
527 if (toklen != 0)
528 goto inval;
529
530 /* attach the payload */
531 for (pptoken = (struct rxrpc_key_token **)&prep->payload.data[0];
532 *pptoken;
533 pptoken = &(*pptoken)->next)
534 continue;
535 *pptoken = token;
536 if (token->kad->expiry < prep->expiry)
537 prep->expiry = token->kad->expiry;
538
539 _leave(" = 0");
540 return 0;
541
542 inval:
543 ret = -EINVAL;
544 error:
545 rxrpc_rxk5_free(rxk5);
546 kfree(token);
547 _leave(" = %d", ret);
548 return ret;
549 }
550
551 /*
552 * attempt to parse the data as the XDR format
553 * - the caller guarantees we have more than 7 words
554 */
555 static int rxrpc_preparse_xdr(struct key_preparsed_payload *prep)
556 {
557 const __be32 *xdr = prep->data, *token;
558 const char *cp;
559 unsigned int len, paddedlen, loop, ntoken, toklen, sec_ix;
560 size_t datalen = prep->datalen;
561 int ret;
562
563 _enter(",{%x,%x,%x,%x},%zu",
564 ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
565 prep->datalen);
566
567 if (datalen > AFSTOKEN_LENGTH_MAX)
568 goto not_xdr;
569
570 /* XDR is an array of __be32's */
571 if (datalen & 3)
572 goto not_xdr;
573
574 /* the flags should be 0 (the setpag bit must be handled by
575 * userspace) */
576 if (ntohl(*xdr++) != 0)
577 goto not_xdr;
578 datalen -= 4;
579
580 /* check the cell name */
581 len = ntohl(*xdr++);
582 if (len < 1 || len > AFSTOKEN_CELL_MAX)
583 goto not_xdr;
584 datalen -= 4;
585 paddedlen = (len + 3) & ~3;
586 if (paddedlen > datalen)
587 goto not_xdr;
588
589 cp = (const char *) xdr;
590 for (loop = 0; loop < len; loop++)
591 if (!isprint(cp[loop]))
592 goto not_xdr;
593 for (; loop < paddedlen; loop++)
594 if (cp[loop])
595 goto not_xdr;
596 _debug("cellname: [%u/%u] '%*.*s'",
597 len, paddedlen, len, len, (const char *) xdr);
598 datalen -= paddedlen;
599 xdr += paddedlen >> 2;
600
601 /* get the token count */
602 if (datalen < 12)
603 goto not_xdr;
604 ntoken = ntohl(*xdr++);
605 datalen -= 4;
606 _debug("ntoken: %x", ntoken);
607 if (ntoken < 1 || ntoken > AFSTOKEN_MAX)
608 goto not_xdr;
609
610 /* check each token wrapper */
611 token = xdr;
612 loop = ntoken;
613 do {
614 if (datalen < 8)
615 goto not_xdr;
616 toklen = ntohl(*xdr++);
617 sec_ix = ntohl(*xdr);
618 datalen -= 4;
619 _debug("token: [%x/%zx] %x", toklen, datalen, sec_ix);
620 paddedlen = (toklen + 3) & ~3;
621 if (toklen < 20 || toklen > datalen || paddedlen > datalen)
622 goto not_xdr;
623 datalen -= paddedlen;
624 xdr += paddedlen >> 2;
625
626 } while (--loop > 0);
627
628 _debug("remainder: %zu", datalen);
629 if (datalen != 0)
630 goto not_xdr;
631
632 /* okay: we're going to assume it's valid XDR format
633 * - we ignore the cellname, relying on the key to be correctly named
634 */
635 do {
636 xdr = token;
637 toklen = ntohl(*xdr++);
638 token = xdr + ((toklen + 3) >> 2);
639 sec_ix = ntohl(*xdr++);
640 toklen -= 4;
641
642 _debug("TOKEN type=%u [%p-%p]", sec_ix, xdr, token);
643
644 switch (sec_ix) {
645 case RXRPC_SECURITY_RXKAD:
646 ret = rxrpc_preparse_xdr_rxkad(prep, datalen, xdr, toklen);
647 if (ret != 0)
648 goto error;
649 break;
650
651 case RXRPC_SECURITY_RXK5:
652 ret = rxrpc_preparse_xdr_rxk5(prep, datalen, xdr, toklen);
653 if (ret != 0)
654 goto error;
655 break;
656
657 default:
658 ret = -EPROTONOSUPPORT;
659 goto error;
660 }
661
662 } while (--ntoken > 0);
663
664 _leave(" = 0");
665 return 0;
666
667 not_xdr:
668 _leave(" = -EPROTO");
669 return -EPROTO;
670 error:
671 _leave(" = %d", ret);
672 return ret;
673 }
674
675 /*
676 * Preparse an rxrpc defined key.
677 *
678 * Data should be of the form:
679 * OFFSET LEN CONTENT
680 * 0 4 key interface version number
681 * 4 2 security index (type)
682 * 6 2 ticket length
683 * 8 4 key expiry time (time_t)
684 * 12 4 kvno
685 * 16 8 session key
686 * 24 [len] ticket
687 *
688 * if no data is provided, then a no-security key is made
689 */
690 static int rxrpc_preparse(struct key_preparsed_payload *prep)
691 {
692 const struct rxrpc_key_data_v1 *v1;
693 struct rxrpc_key_token *token, **pp;
694 size_t plen;
695 u32 kver;
696 int ret;
697
698 _enter("%zu", prep->datalen);
699
700 /* handle a no-security key */
701 if (!prep->data && prep->datalen == 0)
702 return 0;
703
704 /* determine if the XDR payload format is being used */
705 if (prep->datalen > 7 * 4) {
706 ret = rxrpc_preparse_xdr(prep);
707 if (ret != -EPROTO)
708 return ret;
709 }
710
711 /* get the key interface version number */
712 ret = -EINVAL;
713 if (prep->datalen <= 4 || !prep->data)
714 goto error;
715 memcpy(&kver, prep->data, sizeof(kver));
716 prep->data += sizeof(kver);
717 prep->datalen -= sizeof(kver);
718
719 _debug("KEY I/F VERSION: %u", kver);
720
721 ret = -EKEYREJECTED;
722 if (kver != 1)
723 goto error;
724
725 /* deal with a version 1 key */
726 ret = -EINVAL;
727 if (prep->datalen < sizeof(*v1))
728 goto error;
729
730 v1 = prep->data;
731 if (prep->datalen != sizeof(*v1) + v1->ticket_length)
732 goto error;
733
734 _debug("SCIX: %u", v1->security_index);
735 _debug("TLEN: %u", v1->ticket_length);
736 _debug("EXPY: %x", v1->expiry);
737 _debug("KVNO: %u", v1->kvno);
738 _debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
739 v1->session_key[0], v1->session_key[1],
740 v1->session_key[2], v1->session_key[3],
741 v1->session_key[4], v1->session_key[5],
742 v1->session_key[6], v1->session_key[7]);
743 if (v1->ticket_length >= 8)
744 _debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
745 v1->ticket[0], v1->ticket[1],
746 v1->ticket[2], v1->ticket[3],
747 v1->ticket[4], v1->ticket[5],
748 v1->ticket[6], v1->ticket[7]);
749
750 ret = -EPROTONOSUPPORT;
751 if (v1->security_index != RXRPC_SECURITY_RXKAD)
752 goto error;
753
754 plen = sizeof(*token->kad) + v1->ticket_length;
755 prep->quotalen = plen + sizeof(*token);
756
757 ret = -ENOMEM;
758 token = kzalloc(sizeof(*token), GFP_KERNEL);
759 if (!token)
760 goto error;
761 token->kad = kzalloc(plen, GFP_KERNEL);
762 if (!token->kad)
763 goto error_free;
764
765 token->security_index = RXRPC_SECURITY_RXKAD;
766 token->kad->ticket_len = v1->ticket_length;
767 token->kad->expiry = v1->expiry;
768 token->kad->kvno = v1->kvno;
769 memcpy(&token->kad->session_key, &v1->session_key, 8);
770 memcpy(&token->kad->ticket, v1->ticket, v1->ticket_length);
771
772 /* count the number of tokens attached */
773 prep->payload.data[1] = (void *)((unsigned long)prep->payload.data[1] + 1);
774
775 /* attach the data */
776 pp = (struct rxrpc_key_token **)&prep->payload.data[0];
777 while (*pp)
778 pp = &(*pp)->next;
779 *pp = token;
780 if (token->kad->expiry < prep->expiry)
781 prep->expiry = token->kad->expiry;
782 token = NULL;
783 ret = 0;
784
785 error_free:
786 kfree(token);
787 error:
788 return ret;
789 }
790
791 /*
792 * Free token list.
793 */
794 static void rxrpc_free_token_list(struct rxrpc_key_token *token)
795 {
796 struct rxrpc_key_token *next;
797
798 for (; token; token = next) {
799 next = token->next;
800 switch (token->security_index) {
801 case RXRPC_SECURITY_RXKAD:
802 kfree(token->kad);
803 break;
804 case RXRPC_SECURITY_RXK5:
805 if (token->k5)
806 rxrpc_rxk5_free(token->k5);
807 break;
808 default:
809 pr_err("Unknown token type %x on rxrpc key\n",
810 token->security_index);
811 BUG();
812 }
813
814 kfree(token);
815 }
816 }
817
818 /*
819 * Clean up preparse data.
820 */
821 static void rxrpc_free_preparse(struct key_preparsed_payload *prep)
822 {
823 rxrpc_free_token_list(prep->payload.data[0]);
824 }
825
826 /*
827 * Preparse a server secret key.
828 *
829 * The data should be the 8-byte secret key.
830 */
831 static int rxrpc_preparse_s(struct key_preparsed_payload *prep)
832 {
833 struct crypto_skcipher *ci;
834
835 _enter("%zu", prep->datalen);
836
837 if (prep->datalen != 8)
838 return -EINVAL;
839
840 memcpy(&prep->payload.data[2], prep->data, 8);
841
842 ci = crypto_alloc_skcipher("pcbc(des)", 0, CRYPTO_ALG_ASYNC);
843 if (IS_ERR(ci)) {
844 _leave(" = %ld", PTR_ERR(ci));
845 return PTR_ERR(ci);
846 }
847
848 if (crypto_skcipher_setkey(ci, prep->data, 8) < 0)
849 BUG();
850
851 prep->payload.data[0] = ci;
852 _leave(" = 0");
853 return 0;
854 }
855
856 /*
857 * Clean up preparse data.
858 */
859 static void rxrpc_free_preparse_s(struct key_preparsed_payload *prep)
860 {
861 if (prep->payload.data[0])
862 crypto_free_skcipher(prep->payload.data[0]);
863 }
864
865 /*
866 * dispose of the data dangling from the corpse of a rxrpc key
867 */
868 static void rxrpc_destroy(struct key *key)
869 {
870 rxrpc_free_token_list(key->payload.data[0]);
871 }
872
873 /*
874 * dispose of the data dangling from the corpse of a rxrpc key
875 */
876 static void rxrpc_destroy_s(struct key *key)
877 {
878 if (key->payload.data[0]) {
879 crypto_free_skcipher(key->payload.data[0]);
880 key->payload.data[0] = NULL;
881 }
882 }
883
884 /*
885 * describe the rxrpc key
886 */
887 static void rxrpc_describe(const struct key *key, struct seq_file *m)
888 {
889 seq_puts(m, key->description);
890 }
891
892 /*
893 * grab the security key for a socket
894 */
895 int rxrpc_request_key(struct rxrpc_sock *rx, char __user *optval, int optlen)
896 {
897 struct key *key;
898 char *description;
899
900 _enter("");
901
902 if (optlen <= 0 || optlen > PAGE_SIZE - 1)
903 return -EINVAL;
904
905 description = memdup_user_nul(optval, optlen);
906 if (IS_ERR(description))
907 return PTR_ERR(description);
908
909 key = request_key(&key_type_rxrpc, description, NULL);
910 if (IS_ERR(key)) {
911 kfree(description);
912 _leave(" = %ld", PTR_ERR(key));
913 return PTR_ERR(key);
914 }
915
916 rx->key = key;
917 kfree(description);
918 _leave(" = 0 [key %x]", key->serial);
919 return 0;
920 }
921
922 /*
923 * grab the security keyring for a server socket
924 */
925 int rxrpc_server_keyring(struct rxrpc_sock *rx, char __user *optval,
926 int optlen)
927 {
928 struct key *key;
929 char *description;
930
931 _enter("");
932
933 if (optlen <= 0 || optlen > PAGE_SIZE - 1)
934 return -EINVAL;
935
936 description = memdup_user_nul(optval, optlen);
937 if (IS_ERR(description))
938 return PTR_ERR(description);
939
940 key = request_key(&key_type_keyring, description, NULL);
941 if (IS_ERR(key)) {
942 kfree(description);
943 _leave(" = %ld", PTR_ERR(key));
944 return PTR_ERR(key);
945 }
946
947 rx->securities = key;
948 kfree(description);
949 _leave(" = 0 [key %x]", key->serial);
950 return 0;
951 }
952
953 /*
954 * generate a server data key
955 */
956 int rxrpc_get_server_data_key(struct rxrpc_connection *conn,
957 const void *session_key,
958 time_t expiry,
959 u32 kvno)
960 {
961 const struct cred *cred = current_cred();
962 struct key *key;
963 int ret;
964
965 struct {
966 u32 kver;
967 struct rxrpc_key_data_v1 v1;
968 } data;
969
970 _enter("");
971
972 key = key_alloc(&key_type_rxrpc, "x",
973 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, 0,
974 KEY_ALLOC_NOT_IN_QUOTA, NULL);
975 if (IS_ERR(key)) {
976 _leave(" = -ENOMEM [alloc %ld]", PTR_ERR(key));
977 return -ENOMEM;
978 }
979
980 _debug("key %d", key_serial(key));
981
982 data.kver = 1;
983 data.v1.security_index = RXRPC_SECURITY_RXKAD;
984 data.v1.ticket_length = 0;
985 data.v1.expiry = expiry;
986 data.v1.kvno = 0;
987
988 memcpy(&data.v1.session_key, session_key, sizeof(data.v1.session_key));
989
990 ret = key_instantiate_and_link(key, &data, sizeof(data), NULL, NULL);
991 if (ret < 0)
992 goto error;
993
994 conn->params.key = key;
995 _leave(" = 0 [%d]", key_serial(key));
996 return 0;
997
998 error:
999 key_revoke(key);
1000 key_put(key);
1001 _leave(" = -ENOMEM [ins %d]", ret);
1002 return -ENOMEM;
1003 }
1004 EXPORT_SYMBOL(rxrpc_get_server_data_key);
1005
1006 /**
1007 * rxrpc_get_null_key - Generate a null RxRPC key
1008 * @keyname: The name to give the key.
1009 *
1010 * Generate a null RxRPC key that can be used to indicate anonymous security is
1011 * required for a particular domain.
1012 */
1013 struct key *rxrpc_get_null_key(const char *keyname)
1014 {
1015 const struct cred *cred = current_cred();
1016 struct key *key;
1017 int ret;
1018
1019 key = key_alloc(&key_type_rxrpc, keyname,
1020 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
1021 KEY_POS_SEARCH, KEY_ALLOC_NOT_IN_QUOTA, NULL);
1022 if (IS_ERR(key))
1023 return key;
1024
1025 ret = key_instantiate_and_link(key, NULL, 0, NULL, NULL);
1026 if (ret < 0) {
1027 key_revoke(key);
1028 key_put(key);
1029 return ERR_PTR(ret);
1030 }
1031
1032 return key;
1033 }
1034 EXPORT_SYMBOL(rxrpc_get_null_key);
1035
1036 /*
1037 * read the contents of an rxrpc key
1038 * - this returns the result in XDR form
1039 */
1040 static long rxrpc_read(const struct key *key,
1041 char __user *buffer, size_t buflen)
1042 {
1043 const struct rxrpc_key_token *token;
1044 const struct krb5_principal *princ;
1045 size_t size;
1046 __be32 __user *xdr, *oldxdr;
1047 u32 cnlen, toksize, ntoks, tok, zero;
1048 u16 toksizes[AFSTOKEN_MAX];
1049 int loop;
1050
1051 _enter("");
1052
1053 /* we don't know what form we should return non-AFS keys in */
1054 if (memcmp(key->description, "afs@", 4) != 0)
1055 return -EOPNOTSUPP;
1056 cnlen = strlen(key->description + 4);
1057
1058 #define RND(X) (((X) + 3) & ~3)
1059
1060 /* AFS keys we return in XDR form, so we need to work out the size of
1061 * the XDR */
1062 size = 2 * 4; /* flags, cellname len */
1063 size += RND(cnlen); /* cellname */
1064 size += 1 * 4; /* token count */
1065
1066 ntoks = 0;
1067 for (token = key->payload.data[0]; token; token = token->next) {
1068 toksize = 4; /* sec index */
1069
1070 switch (token->security_index) {
1071 case RXRPC_SECURITY_RXKAD:
1072 toksize += 9 * 4; /* viceid, kvno, key*2 + len, begin,
1073 * end, primary, tktlen */
1074 toksize += RND(token->kad->ticket_len);
1075 break;
1076
1077 case RXRPC_SECURITY_RXK5:
1078 princ = &token->k5->client;
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 princ = &token->k5->server;
1085 toksize += 4 + princ->n_name_parts * 4;
1086 for (loop = 0; loop < princ->n_name_parts; loop++)
1087 toksize += RND(strlen(princ->name_parts[loop]));
1088 toksize += 4 + RND(strlen(princ->realm));
1089
1090 toksize += 8 + RND(token->k5->session.data_len);
1091
1092 toksize += 4 * 8 + 2 * 4;
1093
1094 toksize += 4 + token->k5->n_addresses * 8;
1095 for (loop = 0; loop < token->k5->n_addresses; loop++)
1096 toksize += RND(token->k5->addresses[loop].data_len);
1097
1098 toksize += 4 + RND(token->k5->ticket_len);
1099 toksize += 4 + RND(token->k5->ticket2_len);
1100
1101 toksize += 4 + token->k5->n_authdata * 8;
1102 for (loop = 0; loop < token->k5->n_authdata; loop++)
1103 toksize += RND(token->k5->authdata[loop].data_len);
1104 break;
1105
1106 default: /* we have a ticket we can't encode */
1107 BUG();
1108 continue;
1109 }
1110
1111 _debug("token[%u]: toksize=%u", ntoks, toksize);
1112 ASSERTCMP(toksize, <=, AFSTOKEN_LENGTH_MAX);
1113
1114 toksizes[ntoks++] = toksize;
1115 size += toksize + 4; /* each token has a length word */
1116 }
1117
1118 #undef RND
1119
1120 if (!buffer || buflen < size)
1121 return size;
1122
1123 xdr = (__be32 __user *) buffer;
1124 zero = 0;
1125 #define ENCODE(x) \
1126 do { \
1127 __be32 y = htonl(x); \
1128 if (put_user(y, xdr++) < 0) \
1129 goto fault; \
1130 } while(0)
1131 #define ENCODE_DATA(l, s) \
1132 do { \
1133 u32 _l = (l); \
1134 ENCODE(l); \
1135 if (copy_to_user(xdr, (s), _l) != 0) \
1136 goto fault; \
1137 if (_l & 3 && \
1138 copy_to_user((u8 __user *)xdr + _l, &zero, 4 - (_l & 3)) != 0) \
1139 goto fault; \
1140 xdr += (_l + 3) >> 2; \
1141 } while(0)
1142 #define ENCODE64(x) \
1143 do { \
1144 __be64 y = cpu_to_be64(x); \
1145 if (copy_to_user(xdr, &y, 8) != 0) \
1146 goto fault; \
1147 xdr += 8 >> 2; \
1148 } while(0)
1149 #define ENCODE_STR(s) \
1150 do { \
1151 const char *_s = (s); \
1152 ENCODE_DATA(strlen(_s), _s); \
1153 } while(0)
1154
1155 ENCODE(0); /* flags */
1156 ENCODE_DATA(cnlen, key->description + 4); /* cellname */
1157 ENCODE(ntoks);
1158
1159 tok = 0;
1160 for (token = key->payload.data[0]; token; token = token->next) {
1161 toksize = toksizes[tok++];
1162 ENCODE(toksize);
1163 oldxdr = xdr;
1164 ENCODE(token->security_index);
1165
1166 switch (token->security_index) {
1167 case RXRPC_SECURITY_RXKAD:
1168 ENCODE(token->kad->vice_id);
1169 ENCODE(token->kad->kvno);
1170 ENCODE_DATA(8, token->kad->session_key);
1171 ENCODE(token->kad->start);
1172 ENCODE(token->kad->expiry);
1173 ENCODE(token->kad->primary_flag);
1174 ENCODE_DATA(token->kad->ticket_len, token->kad->ticket);
1175 break;
1176
1177 case RXRPC_SECURITY_RXK5:
1178 princ = &token->k5->client;
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 princ = &token->k5->server;
1185 ENCODE(princ->n_name_parts);
1186 for (loop = 0; loop < princ->n_name_parts; loop++)
1187 ENCODE_STR(princ->name_parts[loop]);
1188 ENCODE_STR(princ->realm);
1189
1190 ENCODE(token->k5->session.tag);
1191 ENCODE_DATA(token->k5->session.data_len,
1192 token->k5->session.data);
1193
1194 ENCODE64(token->k5->authtime);
1195 ENCODE64(token->k5->starttime);
1196 ENCODE64(token->k5->endtime);
1197 ENCODE64(token->k5->renew_till);
1198 ENCODE(token->k5->is_skey);
1199 ENCODE(token->k5->flags);
1200
1201 ENCODE(token->k5->n_addresses);
1202 for (loop = 0; loop < token->k5->n_addresses; loop++) {
1203 ENCODE(token->k5->addresses[loop].tag);
1204 ENCODE_DATA(token->k5->addresses[loop].data_len,
1205 token->k5->addresses[loop].data);
1206 }
1207
1208 ENCODE_DATA(token->k5->ticket_len, token->k5->ticket);
1209 ENCODE_DATA(token->k5->ticket2_len, token->k5->ticket2);
1210
1211 ENCODE(token->k5->n_authdata);
1212 for (loop = 0; loop < token->k5->n_authdata; loop++) {
1213 ENCODE(token->k5->authdata[loop].tag);
1214 ENCODE_DATA(token->k5->authdata[loop].data_len,
1215 token->k5->authdata[loop].data);
1216 }
1217 break;
1218
1219 default:
1220 BUG();
1221 break;
1222 }
1223
1224 ASSERTCMP((unsigned long)xdr - (unsigned long)oldxdr, ==,
1225 toksize);
1226 }
1227
1228 #undef ENCODE_STR
1229 #undef ENCODE_DATA
1230 #undef ENCODE64
1231 #undef ENCODE
1232
1233 ASSERTCMP(tok, ==, ntoks);
1234 ASSERTCMP((char __user *) xdr - buffer, ==, size);
1235 _leave(" = %zu", size);
1236 return size;
1237
1238 fault:
1239 _leave(" = -EFAULT");
1240 return -EFAULT;
1241 }
Ubuntu Artful kernel mirror