Loading...
1// SPDX-License-Identifier: BSD-3-Clause
2/*
3 * linux/net/sunrpc/gss_krb5_mech.c
4 *
5 * Copyright (c) 2001-2008 The Regents of the University of Michigan.
6 * All rights reserved.
7 *
8 * Andy Adamson <andros@umich.edu>
9 * J. Bruce Fields <bfields@umich.edu>
10 */
11
12#include <crypto/hash.h>
13#include <crypto/skcipher.h>
14#include <linux/err.h>
15#include <linux/module.h>
16#include <linux/init.h>
17#include <linux/types.h>
18#include <linux/slab.h>
19#include <linux/sunrpc/auth.h>
20#include <linux/sunrpc/gss_krb5.h>
21#include <linux/sunrpc/xdr.h>
22#include <linux/sunrpc/gss_krb5_enctypes.h>
23
24#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
25# define RPCDBG_FACILITY RPCDBG_AUTH
26#endif
27
28static struct gss_api_mech gss_kerberos_mech; /* forward declaration */
29
30static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
31#ifndef CONFIG_SUNRPC_DISABLE_INSECURE_ENCTYPES
32 /*
33 * DES (All DES enctypes are mapped to the same gss functionality)
34 */
35 {
36 .etype = ENCTYPE_DES_CBC_RAW,
37 .ctype = CKSUMTYPE_RSA_MD5,
38 .name = "des-cbc-crc",
39 .encrypt_name = "cbc(des)",
40 .cksum_name = "md5",
41 .encrypt = krb5_encrypt,
42 .decrypt = krb5_decrypt,
43 .mk_key = NULL,
44 .signalg = SGN_ALG_DES_MAC_MD5,
45 .sealalg = SEAL_ALG_DES,
46 .keybytes = 7,
47 .keylength = 8,
48 .blocksize = 8,
49 .conflen = 8,
50 .cksumlength = 8,
51 .keyed_cksum = 0,
52 },
53#endif /* CONFIG_SUNRPC_DISABLE_INSECURE_ENCTYPES */
54 /*
55 * RC4-HMAC
56 */
57 {
58 .etype = ENCTYPE_ARCFOUR_HMAC,
59 .ctype = CKSUMTYPE_HMAC_MD5_ARCFOUR,
60 .name = "rc4-hmac",
61 .encrypt_name = "ecb(arc4)",
62 .cksum_name = "hmac(md5)",
63 .encrypt = krb5_encrypt,
64 .decrypt = krb5_decrypt,
65 .mk_key = NULL,
66 .signalg = SGN_ALG_HMAC_MD5,
67 .sealalg = SEAL_ALG_MICROSOFT_RC4,
68 .keybytes = 16,
69 .keylength = 16,
70 .blocksize = 1,
71 .conflen = 8,
72 .cksumlength = 8,
73 .keyed_cksum = 1,
74 },
75 /*
76 * 3DES
77 */
78 {
79 .etype = ENCTYPE_DES3_CBC_RAW,
80 .ctype = CKSUMTYPE_HMAC_SHA1_DES3,
81 .name = "des3-hmac-sha1",
82 .encrypt_name = "cbc(des3_ede)",
83 .cksum_name = "hmac(sha1)",
84 .encrypt = krb5_encrypt,
85 .decrypt = krb5_decrypt,
86 .mk_key = gss_krb5_des3_make_key,
87 .signalg = SGN_ALG_HMAC_SHA1_DES3_KD,
88 .sealalg = SEAL_ALG_DES3KD,
89 .keybytes = 21,
90 .keylength = 24,
91 .blocksize = 8,
92 .conflen = 8,
93 .cksumlength = 20,
94 .keyed_cksum = 1,
95 },
96 /*
97 * AES128
98 */
99 {
100 .etype = ENCTYPE_AES128_CTS_HMAC_SHA1_96,
101 .ctype = CKSUMTYPE_HMAC_SHA1_96_AES128,
102 .name = "aes128-cts",
103 .encrypt_name = "cts(cbc(aes))",
104 .cksum_name = "hmac(sha1)",
105 .encrypt = krb5_encrypt,
106 .decrypt = krb5_decrypt,
107 .mk_key = gss_krb5_aes_make_key,
108 .encrypt_v2 = gss_krb5_aes_encrypt,
109 .decrypt_v2 = gss_krb5_aes_decrypt,
110 .signalg = -1,
111 .sealalg = -1,
112 .keybytes = 16,
113 .keylength = 16,
114 .blocksize = 16,
115 .conflen = 16,
116 .cksumlength = 12,
117 .keyed_cksum = 1,
118 },
119 /*
120 * AES256
121 */
122 {
123 .etype = ENCTYPE_AES256_CTS_HMAC_SHA1_96,
124 .ctype = CKSUMTYPE_HMAC_SHA1_96_AES256,
125 .name = "aes256-cts",
126 .encrypt_name = "cts(cbc(aes))",
127 .cksum_name = "hmac(sha1)",
128 .encrypt = krb5_encrypt,
129 .decrypt = krb5_decrypt,
130 .mk_key = gss_krb5_aes_make_key,
131 .encrypt_v2 = gss_krb5_aes_encrypt,
132 .decrypt_v2 = gss_krb5_aes_decrypt,
133 .signalg = -1,
134 .sealalg = -1,
135 .keybytes = 32,
136 .keylength = 32,
137 .blocksize = 16,
138 .conflen = 16,
139 .cksumlength = 12,
140 .keyed_cksum = 1,
141 },
142};
143
144static const int num_supported_enctypes =
145 ARRAY_SIZE(supported_gss_krb5_enctypes);
146
147static int
148supported_gss_krb5_enctype(int etype)
149{
150 int i;
151 for (i = 0; i < num_supported_enctypes; i++)
152 if (supported_gss_krb5_enctypes[i].etype == etype)
153 return 1;
154 return 0;
155}
156
157static const struct gss_krb5_enctype *
158get_gss_krb5_enctype(int etype)
159{
160 int i;
161 for (i = 0; i < num_supported_enctypes; i++)
162 if (supported_gss_krb5_enctypes[i].etype == etype)
163 return &supported_gss_krb5_enctypes[i];
164 return NULL;
165}
166
167static const void *
168simple_get_bytes(const void *p, const void *end, void *res, int len)
169{
170 const void *q = (const void *)((const char *)p + len);
171 if (unlikely(q > end || q < p))
172 return ERR_PTR(-EFAULT);
173 memcpy(res, p, len);
174 return q;
175}
176
177static const void *
178simple_get_netobj(const void *p, const void *end, struct xdr_netobj *res)
179{
180 const void *q;
181 unsigned int len;
182
183 p = simple_get_bytes(p, end, &len, sizeof(len));
184 if (IS_ERR(p))
185 return p;
186 q = (const void *)((const char *)p + len);
187 if (unlikely(q > end || q < p))
188 return ERR_PTR(-EFAULT);
189 res->data = kmemdup(p, len, GFP_NOFS);
190 if (unlikely(res->data == NULL))
191 return ERR_PTR(-ENOMEM);
192 res->len = len;
193 return q;
194}
195
196static inline const void *
197get_key(const void *p, const void *end,
198 struct krb5_ctx *ctx, struct crypto_sync_skcipher **res)
199{
200 struct xdr_netobj key;
201 int alg;
202
203 p = simple_get_bytes(p, end, &alg, sizeof(alg));
204 if (IS_ERR(p))
205 goto out_err;
206
207 switch (alg) {
208 case ENCTYPE_DES_CBC_CRC:
209 case ENCTYPE_DES_CBC_MD4:
210 case ENCTYPE_DES_CBC_MD5:
211 /* Map all these key types to ENCTYPE_DES_CBC_RAW */
212 alg = ENCTYPE_DES_CBC_RAW;
213 break;
214 }
215
216 if (!supported_gss_krb5_enctype(alg)) {
217 printk(KERN_WARNING "gss_kerberos_mech: unsupported "
218 "encryption key algorithm %d\n", alg);
219 p = ERR_PTR(-EINVAL);
220 goto out_err;
221 }
222 p = simple_get_netobj(p, end, &key);
223 if (IS_ERR(p))
224 goto out_err;
225
226 *res = crypto_alloc_sync_skcipher(ctx->gk5e->encrypt_name, 0, 0);
227 if (IS_ERR(*res)) {
228 printk(KERN_WARNING "gss_kerberos_mech: unable to initialize "
229 "crypto algorithm %s\n", ctx->gk5e->encrypt_name);
230 *res = NULL;
231 goto out_err_free_key;
232 }
233 if (crypto_sync_skcipher_setkey(*res, key.data, key.len)) {
234 printk(KERN_WARNING "gss_kerberos_mech: error setting key for "
235 "crypto algorithm %s\n", ctx->gk5e->encrypt_name);
236 goto out_err_free_tfm;
237 }
238
239 kfree(key.data);
240 return p;
241
242out_err_free_tfm:
243 crypto_free_sync_skcipher(*res);
244out_err_free_key:
245 kfree(key.data);
246 p = ERR_PTR(-EINVAL);
247out_err:
248 return p;
249}
250
251static int
252gss_import_v1_context(const void *p, const void *end, struct krb5_ctx *ctx)
253{
254 u32 seq_send;
255 int tmp;
256 u32 time32;
257
258 p = simple_get_bytes(p, end, &ctx->initiate, sizeof(ctx->initiate));
259 if (IS_ERR(p))
260 goto out_err;
261
262 /* Old format supports only DES! Any other enctype uses new format */
263 ctx->enctype = ENCTYPE_DES_CBC_RAW;
264
265 ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
266 if (ctx->gk5e == NULL) {
267 p = ERR_PTR(-EINVAL);
268 goto out_err;
269 }
270
271 /* The downcall format was designed before we completely understood
272 * the uses of the context fields; so it includes some stuff we
273 * just give some minimal sanity-checking, and some we ignore
274 * completely (like the next twenty bytes): */
275 if (unlikely(p + 20 > end || p + 20 < p)) {
276 p = ERR_PTR(-EFAULT);
277 goto out_err;
278 }
279 p += 20;
280 p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
281 if (IS_ERR(p))
282 goto out_err;
283 if (tmp != SGN_ALG_DES_MAC_MD5) {
284 p = ERR_PTR(-ENOSYS);
285 goto out_err;
286 }
287 p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
288 if (IS_ERR(p))
289 goto out_err;
290 if (tmp != SEAL_ALG_DES) {
291 p = ERR_PTR(-ENOSYS);
292 goto out_err;
293 }
294 p = simple_get_bytes(p, end, &time32, sizeof(time32));
295 if (IS_ERR(p))
296 goto out_err;
297 /* unsigned 32-bit time overflows in year 2106 */
298 ctx->endtime = (time64_t)time32;
299 p = simple_get_bytes(p, end, &seq_send, sizeof(seq_send));
300 if (IS_ERR(p))
301 goto out_err;
302 atomic_set(&ctx->seq_send, seq_send);
303 p = simple_get_netobj(p, end, &ctx->mech_used);
304 if (IS_ERR(p))
305 goto out_err;
306 p = get_key(p, end, ctx, &ctx->enc);
307 if (IS_ERR(p))
308 goto out_err_free_mech;
309 p = get_key(p, end, ctx, &ctx->seq);
310 if (IS_ERR(p))
311 goto out_err_free_key1;
312 if (p != end) {
313 p = ERR_PTR(-EFAULT);
314 goto out_err_free_key2;
315 }
316
317 return 0;
318
319out_err_free_key2:
320 crypto_free_sync_skcipher(ctx->seq);
321out_err_free_key1:
322 crypto_free_sync_skcipher(ctx->enc);
323out_err_free_mech:
324 kfree(ctx->mech_used.data);
325out_err:
326 return PTR_ERR(p);
327}
328
329static struct crypto_sync_skcipher *
330context_v2_alloc_cipher(struct krb5_ctx *ctx, const char *cname, u8 *key)
331{
332 struct crypto_sync_skcipher *cp;
333
334 cp = crypto_alloc_sync_skcipher(cname, 0, 0);
335 if (IS_ERR(cp)) {
336 dprintk("gss_kerberos_mech: unable to initialize "
337 "crypto algorithm %s\n", cname);
338 return NULL;
339 }
340 if (crypto_sync_skcipher_setkey(cp, key, ctx->gk5e->keylength)) {
341 dprintk("gss_kerberos_mech: error setting key for "
342 "crypto algorithm %s\n", cname);
343 crypto_free_sync_skcipher(cp);
344 return NULL;
345 }
346 return cp;
347}
348
349static inline void
350set_cdata(u8 cdata[GSS_KRB5_K5CLENGTH], u32 usage, u8 seed)
351{
352 cdata[0] = (usage>>24)&0xff;
353 cdata[1] = (usage>>16)&0xff;
354 cdata[2] = (usage>>8)&0xff;
355 cdata[3] = usage&0xff;
356 cdata[4] = seed;
357}
358
359static int
360context_derive_keys_des3(struct krb5_ctx *ctx, gfp_t gfp_mask)
361{
362 struct xdr_netobj c, keyin, keyout;
363 u8 cdata[GSS_KRB5_K5CLENGTH];
364 u32 err;
365
366 c.len = GSS_KRB5_K5CLENGTH;
367 c.data = cdata;
368
369 keyin.data = ctx->Ksess;
370 keyin.len = ctx->gk5e->keylength;
371 keyout.len = ctx->gk5e->keylength;
372
373 /* seq uses the raw key */
374 ctx->seq = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
375 ctx->Ksess);
376 if (ctx->seq == NULL)
377 goto out_err;
378
379 ctx->enc = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
380 ctx->Ksess);
381 if (ctx->enc == NULL)
382 goto out_free_seq;
383
384 /* derive cksum */
385 set_cdata(cdata, KG_USAGE_SIGN, KEY_USAGE_SEED_CHECKSUM);
386 keyout.data = ctx->cksum;
387 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
388 if (err) {
389 dprintk("%s: Error %d deriving cksum key\n",
390 __func__, err);
391 goto out_free_enc;
392 }
393
394 return 0;
395
396out_free_enc:
397 crypto_free_sync_skcipher(ctx->enc);
398out_free_seq:
399 crypto_free_sync_skcipher(ctx->seq);
400out_err:
401 return -EINVAL;
402}
403
404/*
405 * Note that RC4 depends on deriving keys using the sequence
406 * number or the checksum of a token. Therefore, the final keys
407 * cannot be calculated until the token is being constructed!
408 */
409static int
410context_derive_keys_rc4(struct krb5_ctx *ctx)
411{
412 struct crypto_shash *hmac;
413 char sigkeyconstant[] = "signaturekey";
414 int slen = strlen(sigkeyconstant) + 1; /* include null terminator */
415 struct shash_desc *desc;
416 int err;
417
418 dprintk("RPC: %s: entered\n", __func__);
419 /*
420 * derive cksum (aka Ksign) key
421 */
422 hmac = crypto_alloc_shash(ctx->gk5e->cksum_name, 0, 0);
423 if (IS_ERR(hmac)) {
424 dprintk("%s: error %ld allocating hash '%s'\n",
425 __func__, PTR_ERR(hmac), ctx->gk5e->cksum_name);
426 err = PTR_ERR(hmac);
427 goto out_err;
428 }
429
430 err = crypto_shash_setkey(hmac, ctx->Ksess, ctx->gk5e->keylength);
431 if (err)
432 goto out_err_free_hmac;
433
434
435 desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(hmac), GFP_NOFS);
436 if (!desc) {
437 dprintk("%s: failed to allocate hash descriptor for '%s'\n",
438 __func__, ctx->gk5e->cksum_name);
439 err = -ENOMEM;
440 goto out_err_free_hmac;
441 }
442
443 desc->tfm = hmac;
444
445 err = crypto_shash_digest(desc, sigkeyconstant, slen, ctx->cksum);
446 kfree_sensitive(desc);
447 if (err)
448 goto out_err_free_hmac;
449 /*
450 * allocate hash, and skciphers for data and seqnum encryption
451 */
452 ctx->enc = crypto_alloc_sync_skcipher(ctx->gk5e->encrypt_name, 0, 0);
453 if (IS_ERR(ctx->enc)) {
454 err = PTR_ERR(ctx->enc);
455 goto out_err_free_hmac;
456 }
457
458 ctx->seq = crypto_alloc_sync_skcipher(ctx->gk5e->encrypt_name, 0, 0);
459 if (IS_ERR(ctx->seq)) {
460 crypto_free_sync_skcipher(ctx->enc);
461 err = PTR_ERR(ctx->seq);
462 goto out_err_free_hmac;
463 }
464
465 dprintk("RPC: %s: returning success\n", __func__);
466
467 err = 0;
468
469out_err_free_hmac:
470 crypto_free_shash(hmac);
471out_err:
472 dprintk("RPC: %s: returning %d\n", __func__, err);
473 return err;
474}
475
476static int
477context_derive_keys_new(struct krb5_ctx *ctx, gfp_t gfp_mask)
478{
479 struct xdr_netobj c, keyin, keyout;
480 u8 cdata[GSS_KRB5_K5CLENGTH];
481 u32 err;
482
483 c.len = GSS_KRB5_K5CLENGTH;
484 c.data = cdata;
485
486 keyin.data = ctx->Ksess;
487 keyin.len = ctx->gk5e->keylength;
488 keyout.len = ctx->gk5e->keylength;
489
490 /* initiator seal encryption */
491 set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
492 keyout.data = ctx->initiator_seal;
493 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
494 if (err) {
495 dprintk("%s: Error %d deriving initiator_seal key\n",
496 __func__, err);
497 goto out_err;
498 }
499 ctx->initiator_enc = context_v2_alloc_cipher(ctx,
500 ctx->gk5e->encrypt_name,
501 ctx->initiator_seal);
502 if (ctx->initiator_enc == NULL)
503 goto out_err;
504
505 /* acceptor seal encryption */
506 set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
507 keyout.data = ctx->acceptor_seal;
508 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
509 if (err) {
510 dprintk("%s: Error %d deriving acceptor_seal key\n",
511 __func__, err);
512 goto out_free_initiator_enc;
513 }
514 ctx->acceptor_enc = context_v2_alloc_cipher(ctx,
515 ctx->gk5e->encrypt_name,
516 ctx->acceptor_seal);
517 if (ctx->acceptor_enc == NULL)
518 goto out_free_initiator_enc;
519
520 /* initiator sign checksum */
521 set_cdata(cdata, KG_USAGE_INITIATOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
522 keyout.data = ctx->initiator_sign;
523 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
524 if (err) {
525 dprintk("%s: Error %d deriving initiator_sign key\n",
526 __func__, err);
527 goto out_free_acceptor_enc;
528 }
529
530 /* acceptor sign checksum */
531 set_cdata(cdata, KG_USAGE_ACCEPTOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
532 keyout.data = ctx->acceptor_sign;
533 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
534 if (err) {
535 dprintk("%s: Error %d deriving acceptor_sign key\n",
536 __func__, err);
537 goto out_free_acceptor_enc;
538 }
539
540 /* initiator seal integrity */
541 set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
542 keyout.data = ctx->initiator_integ;
543 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
544 if (err) {
545 dprintk("%s: Error %d deriving initiator_integ key\n",
546 __func__, err);
547 goto out_free_acceptor_enc;
548 }
549
550 /* acceptor seal integrity */
551 set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
552 keyout.data = ctx->acceptor_integ;
553 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
554 if (err) {
555 dprintk("%s: Error %d deriving acceptor_integ key\n",
556 __func__, err);
557 goto out_free_acceptor_enc;
558 }
559
560 switch (ctx->enctype) {
561 case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
562 case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
563 ctx->initiator_enc_aux =
564 context_v2_alloc_cipher(ctx, "cbc(aes)",
565 ctx->initiator_seal);
566 if (ctx->initiator_enc_aux == NULL)
567 goto out_free_acceptor_enc;
568 ctx->acceptor_enc_aux =
569 context_v2_alloc_cipher(ctx, "cbc(aes)",
570 ctx->acceptor_seal);
571 if (ctx->acceptor_enc_aux == NULL) {
572 crypto_free_sync_skcipher(ctx->initiator_enc_aux);
573 goto out_free_acceptor_enc;
574 }
575 }
576
577 return 0;
578
579out_free_acceptor_enc:
580 crypto_free_sync_skcipher(ctx->acceptor_enc);
581out_free_initiator_enc:
582 crypto_free_sync_skcipher(ctx->initiator_enc);
583out_err:
584 return -EINVAL;
585}
586
587static int
588gss_import_v2_context(const void *p, const void *end, struct krb5_ctx *ctx,
589 gfp_t gfp_mask)
590{
591 u64 seq_send64;
592 int keylen;
593 u32 time32;
594
595 p = simple_get_bytes(p, end, &ctx->flags, sizeof(ctx->flags));
596 if (IS_ERR(p))
597 goto out_err;
598 ctx->initiate = ctx->flags & KRB5_CTX_FLAG_INITIATOR;
599
600 p = simple_get_bytes(p, end, &time32, sizeof(time32));
601 if (IS_ERR(p))
602 goto out_err;
603 /* unsigned 32-bit time overflows in year 2106 */
604 ctx->endtime = (time64_t)time32;
605 p = simple_get_bytes(p, end, &seq_send64, sizeof(seq_send64));
606 if (IS_ERR(p))
607 goto out_err;
608 atomic64_set(&ctx->seq_send64, seq_send64);
609 /* set seq_send for use by "older" enctypes */
610 atomic_set(&ctx->seq_send, seq_send64);
611 if (seq_send64 != atomic_read(&ctx->seq_send)) {
612 dprintk("%s: seq_send64 %llx, seq_send %x overflow?\n", __func__,
613 seq_send64, atomic_read(&ctx->seq_send));
614 p = ERR_PTR(-EINVAL);
615 goto out_err;
616 }
617 p = simple_get_bytes(p, end, &ctx->enctype, sizeof(ctx->enctype));
618 if (IS_ERR(p))
619 goto out_err;
620 /* Map ENCTYPE_DES3_CBC_SHA1 to ENCTYPE_DES3_CBC_RAW */
621 if (ctx->enctype == ENCTYPE_DES3_CBC_SHA1)
622 ctx->enctype = ENCTYPE_DES3_CBC_RAW;
623 ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
624 if (ctx->gk5e == NULL) {
625 dprintk("gss_kerberos_mech: unsupported krb5 enctype %u\n",
626 ctx->enctype);
627 p = ERR_PTR(-EINVAL);
628 goto out_err;
629 }
630 keylen = ctx->gk5e->keylength;
631
632 p = simple_get_bytes(p, end, ctx->Ksess, keylen);
633 if (IS_ERR(p))
634 goto out_err;
635
636 if (p != end) {
637 p = ERR_PTR(-EINVAL);
638 goto out_err;
639 }
640
641 ctx->mech_used.data = kmemdup(gss_kerberos_mech.gm_oid.data,
642 gss_kerberos_mech.gm_oid.len, gfp_mask);
643 if (unlikely(ctx->mech_used.data == NULL)) {
644 p = ERR_PTR(-ENOMEM);
645 goto out_err;
646 }
647 ctx->mech_used.len = gss_kerberos_mech.gm_oid.len;
648
649 switch (ctx->enctype) {
650 case ENCTYPE_DES3_CBC_RAW:
651 return context_derive_keys_des3(ctx, gfp_mask);
652 case ENCTYPE_ARCFOUR_HMAC:
653 return context_derive_keys_rc4(ctx);
654 case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
655 case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
656 return context_derive_keys_new(ctx, gfp_mask);
657 default:
658 return -EINVAL;
659 }
660
661out_err:
662 return PTR_ERR(p);
663}
664
665static int
666gss_import_sec_context_kerberos(const void *p, size_t len,
667 struct gss_ctx *ctx_id,
668 time64_t *endtime,
669 gfp_t gfp_mask)
670{
671 const void *end = (const void *)((const char *)p + len);
672 struct krb5_ctx *ctx;
673 int ret;
674
675 ctx = kzalloc(sizeof(*ctx), gfp_mask);
676 if (ctx == NULL)
677 return -ENOMEM;
678
679 if (len == 85)
680 ret = gss_import_v1_context(p, end, ctx);
681 else
682 ret = gss_import_v2_context(p, end, ctx, gfp_mask);
683
684 if (ret == 0) {
685 ctx_id->internal_ctx_id = ctx;
686 if (endtime)
687 *endtime = ctx->endtime;
688 } else
689 kfree(ctx);
690
691 dprintk("RPC: %s: returning %d\n", __func__, ret);
692 return ret;
693}
694
695static void
696gss_delete_sec_context_kerberos(void *internal_ctx) {
697 struct krb5_ctx *kctx = internal_ctx;
698
699 crypto_free_sync_skcipher(kctx->seq);
700 crypto_free_sync_skcipher(kctx->enc);
701 crypto_free_sync_skcipher(kctx->acceptor_enc);
702 crypto_free_sync_skcipher(kctx->initiator_enc);
703 crypto_free_sync_skcipher(kctx->acceptor_enc_aux);
704 crypto_free_sync_skcipher(kctx->initiator_enc_aux);
705 kfree(kctx->mech_used.data);
706 kfree(kctx);
707}
708
709static const struct gss_api_ops gss_kerberos_ops = {
710 .gss_import_sec_context = gss_import_sec_context_kerberos,
711 .gss_get_mic = gss_get_mic_kerberos,
712 .gss_verify_mic = gss_verify_mic_kerberos,
713 .gss_wrap = gss_wrap_kerberos,
714 .gss_unwrap = gss_unwrap_kerberos,
715 .gss_delete_sec_context = gss_delete_sec_context_kerberos,
716};
717
718static struct pf_desc gss_kerberos_pfs[] = {
719 [0] = {
720 .pseudoflavor = RPC_AUTH_GSS_KRB5,
721 .qop = GSS_C_QOP_DEFAULT,
722 .service = RPC_GSS_SVC_NONE,
723 .name = "krb5",
724 },
725 [1] = {
726 .pseudoflavor = RPC_AUTH_GSS_KRB5I,
727 .qop = GSS_C_QOP_DEFAULT,
728 .service = RPC_GSS_SVC_INTEGRITY,
729 .name = "krb5i",
730 .datatouch = true,
731 },
732 [2] = {
733 .pseudoflavor = RPC_AUTH_GSS_KRB5P,
734 .qop = GSS_C_QOP_DEFAULT,
735 .service = RPC_GSS_SVC_PRIVACY,
736 .name = "krb5p",
737 .datatouch = true,
738 },
739};
740
741MODULE_ALIAS("rpc-auth-gss-krb5");
742MODULE_ALIAS("rpc-auth-gss-krb5i");
743MODULE_ALIAS("rpc-auth-gss-krb5p");
744MODULE_ALIAS("rpc-auth-gss-390003");
745MODULE_ALIAS("rpc-auth-gss-390004");
746MODULE_ALIAS("rpc-auth-gss-390005");
747MODULE_ALIAS("rpc-auth-gss-1.2.840.113554.1.2.2");
748
749static struct gss_api_mech gss_kerberos_mech = {
750 .gm_name = "krb5",
751 .gm_owner = THIS_MODULE,
752 .gm_oid = { 9, "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02" },
753 .gm_ops = &gss_kerberos_ops,
754 .gm_pf_num = ARRAY_SIZE(gss_kerberos_pfs),
755 .gm_pfs = gss_kerberos_pfs,
756 .gm_upcall_enctypes = KRB5_SUPPORTED_ENCTYPES,
757};
758
759static int __init init_kerberos_module(void)
760{
761 int status;
762
763 status = gss_mech_register(&gss_kerberos_mech);
764 if (status)
765 printk("Failed to register kerberos gss mechanism!\n");
766 return status;
767}
768
769static void __exit cleanup_kerberos_module(void)
770{
771 gss_mech_unregister(&gss_kerberos_mech);
772}
773
774MODULE_LICENSE("GPL");
775module_init(init_kerberos_module);
776module_exit(cleanup_kerberos_module);
1/*
2 * linux/net/sunrpc/gss_krb5_mech.c
3 *
4 * Copyright (c) 2001-2008 The Regents of the University of Michigan.
5 * All rights reserved.
6 *
7 * Andy Adamson <andros@umich.edu>
8 * J. Bruce Fields <bfields@umich.edu>
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 *
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its
20 * contributors may be used to endorse or promote products derived
21 * from this software without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
24 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
25 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
26 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
30 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 *
35 */
36
37#include <crypto/hash.h>
38#include <crypto/skcipher.h>
39#include <linux/err.h>
40#include <linux/module.h>
41#include <linux/init.h>
42#include <linux/types.h>
43#include <linux/slab.h>
44#include <linux/sunrpc/auth.h>
45#include <linux/sunrpc/gss_krb5.h>
46#include <linux/sunrpc/xdr.h>
47#include <linux/sunrpc/gss_krb5_enctypes.h>
48
49#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
50# define RPCDBG_FACILITY RPCDBG_AUTH
51#endif
52
53static struct gss_api_mech gss_kerberos_mech; /* forward declaration */
54
55static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
56 /*
57 * DES (All DES enctypes are mapped to the same gss functionality)
58 */
59 {
60 .etype = ENCTYPE_DES_CBC_RAW,
61 .ctype = CKSUMTYPE_RSA_MD5,
62 .name = "des-cbc-crc",
63 .encrypt_name = "cbc(des)",
64 .cksum_name = "md5",
65 .encrypt = krb5_encrypt,
66 .decrypt = krb5_decrypt,
67 .mk_key = NULL,
68 .signalg = SGN_ALG_DES_MAC_MD5,
69 .sealalg = SEAL_ALG_DES,
70 .keybytes = 7,
71 .keylength = 8,
72 .blocksize = 8,
73 .conflen = 8,
74 .cksumlength = 8,
75 .keyed_cksum = 0,
76 },
77 /*
78 * RC4-HMAC
79 */
80 {
81 .etype = ENCTYPE_ARCFOUR_HMAC,
82 .ctype = CKSUMTYPE_HMAC_MD5_ARCFOUR,
83 .name = "rc4-hmac",
84 .encrypt_name = "ecb(arc4)",
85 .cksum_name = "hmac(md5)",
86 .encrypt = krb5_encrypt,
87 .decrypt = krb5_decrypt,
88 .mk_key = NULL,
89 .signalg = SGN_ALG_HMAC_MD5,
90 .sealalg = SEAL_ALG_MICROSOFT_RC4,
91 .keybytes = 16,
92 .keylength = 16,
93 .blocksize = 1,
94 .conflen = 8,
95 .cksumlength = 8,
96 .keyed_cksum = 1,
97 },
98 /*
99 * 3DES
100 */
101 {
102 .etype = ENCTYPE_DES3_CBC_RAW,
103 .ctype = CKSUMTYPE_HMAC_SHA1_DES3,
104 .name = "des3-hmac-sha1",
105 .encrypt_name = "cbc(des3_ede)",
106 .cksum_name = "hmac(sha1)",
107 .encrypt = krb5_encrypt,
108 .decrypt = krb5_decrypt,
109 .mk_key = gss_krb5_des3_make_key,
110 .signalg = SGN_ALG_HMAC_SHA1_DES3_KD,
111 .sealalg = SEAL_ALG_DES3KD,
112 .keybytes = 21,
113 .keylength = 24,
114 .blocksize = 8,
115 .conflen = 8,
116 .cksumlength = 20,
117 .keyed_cksum = 1,
118 },
119 /*
120 * AES128
121 */
122 {
123 .etype = ENCTYPE_AES128_CTS_HMAC_SHA1_96,
124 .ctype = CKSUMTYPE_HMAC_SHA1_96_AES128,
125 .name = "aes128-cts",
126 .encrypt_name = "cts(cbc(aes))",
127 .cksum_name = "hmac(sha1)",
128 .encrypt = krb5_encrypt,
129 .decrypt = krb5_decrypt,
130 .mk_key = gss_krb5_aes_make_key,
131 .encrypt_v2 = gss_krb5_aes_encrypt,
132 .decrypt_v2 = gss_krb5_aes_decrypt,
133 .signalg = -1,
134 .sealalg = -1,
135 .keybytes = 16,
136 .keylength = 16,
137 .blocksize = 16,
138 .conflen = 16,
139 .cksumlength = 12,
140 .keyed_cksum = 1,
141 },
142 /*
143 * AES256
144 */
145 {
146 .etype = ENCTYPE_AES256_CTS_HMAC_SHA1_96,
147 .ctype = CKSUMTYPE_HMAC_SHA1_96_AES256,
148 .name = "aes256-cts",
149 .encrypt_name = "cts(cbc(aes))",
150 .cksum_name = "hmac(sha1)",
151 .encrypt = krb5_encrypt,
152 .decrypt = krb5_decrypt,
153 .mk_key = gss_krb5_aes_make_key,
154 .encrypt_v2 = gss_krb5_aes_encrypt,
155 .decrypt_v2 = gss_krb5_aes_decrypt,
156 .signalg = -1,
157 .sealalg = -1,
158 .keybytes = 32,
159 .keylength = 32,
160 .blocksize = 16,
161 .conflen = 16,
162 .cksumlength = 12,
163 .keyed_cksum = 1,
164 },
165};
166
167static const int num_supported_enctypes =
168 ARRAY_SIZE(supported_gss_krb5_enctypes);
169
170static int
171supported_gss_krb5_enctype(int etype)
172{
173 int i;
174 for (i = 0; i < num_supported_enctypes; i++)
175 if (supported_gss_krb5_enctypes[i].etype == etype)
176 return 1;
177 return 0;
178}
179
180static const struct gss_krb5_enctype *
181get_gss_krb5_enctype(int etype)
182{
183 int i;
184 for (i = 0; i < num_supported_enctypes; i++)
185 if (supported_gss_krb5_enctypes[i].etype == etype)
186 return &supported_gss_krb5_enctypes[i];
187 return NULL;
188}
189
190static const void *
191simple_get_bytes(const void *p, const void *end, void *res, int len)
192{
193 const void *q = (const void *)((const char *)p + len);
194 if (unlikely(q > end || q < p))
195 return ERR_PTR(-EFAULT);
196 memcpy(res, p, len);
197 return q;
198}
199
200static const void *
201simple_get_netobj(const void *p, const void *end, struct xdr_netobj *res)
202{
203 const void *q;
204 unsigned int len;
205
206 p = simple_get_bytes(p, end, &len, sizeof(len));
207 if (IS_ERR(p))
208 return p;
209 q = (const void *)((const char *)p + len);
210 if (unlikely(q > end || q < p))
211 return ERR_PTR(-EFAULT);
212 res->data = kmemdup(p, len, GFP_NOFS);
213 if (unlikely(res->data == NULL))
214 return ERR_PTR(-ENOMEM);
215 res->len = len;
216 return q;
217}
218
219static inline const void *
220get_key(const void *p, const void *end,
221 struct krb5_ctx *ctx, struct crypto_skcipher **res)
222{
223 struct xdr_netobj key;
224 int alg;
225
226 p = simple_get_bytes(p, end, &alg, sizeof(alg));
227 if (IS_ERR(p))
228 goto out_err;
229
230 switch (alg) {
231 case ENCTYPE_DES_CBC_CRC:
232 case ENCTYPE_DES_CBC_MD4:
233 case ENCTYPE_DES_CBC_MD5:
234 /* Map all these key types to ENCTYPE_DES_CBC_RAW */
235 alg = ENCTYPE_DES_CBC_RAW;
236 break;
237 }
238
239 if (!supported_gss_krb5_enctype(alg)) {
240 printk(KERN_WARNING "gss_kerberos_mech: unsupported "
241 "encryption key algorithm %d\n", alg);
242 p = ERR_PTR(-EINVAL);
243 goto out_err;
244 }
245 p = simple_get_netobj(p, end, &key);
246 if (IS_ERR(p))
247 goto out_err;
248
249 *res = crypto_alloc_skcipher(ctx->gk5e->encrypt_name, 0,
250 CRYPTO_ALG_ASYNC);
251 if (IS_ERR(*res)) {
252 printk(KERN_WARNING "gss_kerberos_mech: unable to initialize "
253 "crypto algorithm %s\n", ctx->gk5e->encrypt_name);
254 *res = NULL;
255 goto out_err_free_key;
256 }
257 if (crypto_skcipher_setkey(*res, key.data, key.len)) {
258 printk(KERN_WARNING "gss_kerberos_mech: error setting key for "
259 "crypto algorithm %s\n", ctx->gk5e->encrypt_name);
260 goto out_err_free_tfm;
261 }
262
263 kfree(key.data);
264 return p;
265
266out_err_free_tfm:
267 crypto_free_skcipher(*res);
268out_err_free_key:
269 kfree(key.data);
270 p = ERR_PTR(-EINVAL);
271out_err:
272 return p;
273}
274
275static int
276gss_import_v1_context(const void *p, const void *end, struct krb5_ctx *ctx)
277{
278 int tmp;
279
280 p = simple_get_bytes(p, end, &ctx->initiate, sizeof(ctx->initiate));
281 if (IS_ERR(p))
282 goto out_err;
283
284 /* Old format supports only DES! Any other enctype uses new format */
285 ctx->enctype = ENCTYPE_DES_CBC_RAW;
286
287 ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
288 if (ctx->gk5e == NULL) {
289 p = ERR_PTR(-EINVAL);
290 goto out_err;
291 }
292
293 /* The downcall format was designed before we completely understood
294 * the uses of the context fields; so it includes some stuff we
295 * just give some minimal sanity-checking, and some we ignore
296 * completely (like the next twenty bytes): */
297 if (unlikely(p + 20 > end || p + 20 < p)) {
298 p = ERR_PTR(-EFAULT);
299 goto out_err;
300 }
301 p += 20;
302 p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
303 if (IS_ERR(p))
304 goto out_err;
305 if (tmp != SGN_ALG_DES_MAC_MD5) {
306 p = ERR_PTR(-ENOSYS);
307 goto out_err;
308 }
309 p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
310 if (IS_ERR(p))
311 goto out_err;
312 if (tmp != SEAL_ALG_DES) {
313 p = ERR_PTR(-ENOSYS);
314 goto out_err;
315 }
316 p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
317 if (IS_ERR(p))
318 goto out_err;
319 p = simple_get_bytes(p, end, &ctx->seq_send, sizeof(ctx->seq_send));
320 if (IS_ERR(p))
321 goto out_err;
322 p = simple_get_netobj(p, end, &ctx->mech_used);
323 if (IS_ERR(p))
324 goto out_err;
325 p = get_key(p, end, ctx, &ctx->enc);
326 if (IS_ERR(p))
327 goto out_err_free_mech;
328 p = get_key(p, end, ctx, &ctx->seq);
329 if (IS_ERR(p))
330 goto out_err_free_key1;
331 if (p != end) {
332 p = ERR_PTR(-EFAULT);
333 goto out_err_free_key2;
334 }
335
336 return 0;
337
338out_err_free_key2:
339 crypto_free_skcipher(ctx->seq);
340out_err_free_key1:
341 crypto_free_skcipher(ctx->enc);
342out_err_free_mech:
343 kfree(ctx->mech_used.data);
344out_err:
345 return PTR_ERR(p);
346}
347
348static struct crypto_skcipher *
349context_v2_alloc_cipher(struct krb5_ctx *ctx, const char *cname, u8 *key)
350{
351 struct crypto_skcipher *cp;
352
353 cp = crypto_alloc_skcipher(cname, 0, CRYPTO_ALG_ASYNC);
354 if (IS_ERR(cp)) {
355 dprintk("gss_kerberos_mech: unable to initialize "
356 "crypto algorithm %s\n", cname);
357 return NULL;
358 }
359 if (crypto_skcipher_setkey(cp, key, ctx->gk5e->keylength)) {
360 dprintk("gss_kerberos_mech: error setting key for "
361 "crypto algorithm %s\n", cname);
362 crypto_free_skcipher(cp);
363 return NULL;
364 }
365 return cp;
366}
367
368static inline void
369set_cdata(u8 cdata[GSS_KRB5_K5CLENGTH], u32 usage, u8 seed)
370{
371 cdata[0] = (usage>>24)&0xff;
372 cdata[1] = (usage>>16)&0xff;
373 cdata[2] = (usage>>8)&0xff;
374 cdata[3] = usage&0xff;
375 cdata[4] = seed;
376}
377
378static int
379context_derive_keys_des3(struct krb5_ctx *ctx, gfp_t gfp_mask)
380{
381 struct xdr_netobj c, keyin, keyout;
382 u8 cdata[GSS_KRB5_K5CLENGTH];
383 u32 err;
384
385 c.len = GSS_KRB5_K5CLENGTH;
386 c.data = cdata;
387
388 keyin.data = ctx->Ksess;
389 keyin.len = ctx->gk5e->keylength;
390 keyout.len = ctx->gk5e->keylength;
391
392 /* seq uses the raw key */
393 ctx->seq = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
394 ctx->Ksess);
395 if (ctx->seq == NULL)
396 goto out_err;
397
398 ctx->enc = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
399 ctx->Ksess);
400 if (ctx->enc == NULL)
401 goto out_free_seq;
402
403 /* derive cksum */
404 set_cdata(cdata, KG_USAGE_SIGN, KEY_USAGE_SEED_CHECKSUM);
405 keyout.data = ctx->cksum;
406 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
407 if (err) {
408 dprintk("%s: Error %d deriving cksum key\n",
409 __func__, err);
410 goto out_free_enc;
411 }
412
413 return 0;
414
415out_free_enc:
416 crypto_free_skcipher(ctx->enc);
417out_free_seq:
418 crypto_free_skcipher(ctx->seq);
419out_err:
420 return -EINVAL;
421}
422
423/*
424 * Note that RC4 depends on deriving keys using the sequence
425 * number or the checksum of a token. Therefore, the final keys
426 * cannot be calculated until the token is being constructed!
427 */
428static int
429context_derive_keys_rc4(struct krb5_ctx *ctx)
430{
431 struct crypto_shash *hmac;
432 char sigkeyconstant[] = "signaturekey";
433 int slen = strlen(sigkeyconstant) + 1; /* include null terminator */
434 struct shash_desc *desc;
435 int err;
436
437 dprintk("RPC: %s: entered\n", __func__);
438 /*
439 * derive cksum (aka Ksign) key
440 */
441 hmac = crypto_alloc_shash(ctx->gk5e->cksum_name, 0, 0);
442 if (IS_ERR(hmac)) {
443 dprintk("%s: error %ld allocating hash '%s'\n",
444 __func__, PTR_ERR(hmac), ctx->gk5e->cksum_name);
445 err = PTR_ERR(hmac);
446 goto out_err;
447 }
448
449 err = crypto_shash_setkey(hmac, ctx->Ksess, ctx->gk5e->keylength);
450 if (err)
451 goto out_err_free_hmac;
452
453
454 desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(hmac),
455 GFP_KERNEL);
456 if (!desc) {
457 dprintk("%s: failed to allocate hash descriptor for '%s'\n",
458 __func__, ctx->gk5e->cksum_name);
459 err = -ENOMEM;
460 goto out_err_free_hmac;
461 }
462
463 desc->tfm = hmac;
464 desc->flags = 0;
465
466 err = crypto_shash_digest(desc, sigkeyconstant, slen, ctx->cksum);
467 kzfree(desc);
468 if (err)
469 goto out_err_free_hmac;
470 /*
471 * allocate hash, and skciphers for data and seqnum encryption
472 */
473 ctx->enc = crypto_alloc_skcipher(ctx->gk5e->encrypt_name, 0,
474 CRYPTO_ALG_ASYNC);
475 if (IS_ERR(ctx->enc)) {
476 err = PTR_ERR(ctx->enc);
477 goto out_err_free_hmac;
478 }
479
480 ctx->seq = crypto_alloc_skcipher(ctx->gk5e->encrypt_name, 0,
481 CRYPTO_ALG_ASYNC);
482 if (IS_ERR(ctx->seq)) {
483 crypto_free_skcipher(ctx->enc);
484 err = PTR_ERR(ctx->seq);
485 goto out_err_free_hmac;
486 }
487
488 dprintk("RPC: %s: returning success\n", __func__);
489
490 err = 0;
491
492out_err_free_hmac:
493 crypto_free_shash(hmac);
494out_err:
495 dprintk("RPC: %s: returning %d\n", __func__, err);
496 return err;
497}
498
499static int
500context_derive_keys_new(struct krb5_ctx *ctx, gfp_t gfp_mask)
501{
502 struct xdr_netobj c, keyin, keyout;
503 u8 cdata[GSS_KRB5_K5CLENGTH];
504 u32 err;
505
506 c.len = GSS_KRB5_K5CLENGTH;
507 c.data = cdata;
508
509 keyin.data = ctx->Ksess;
510 keyin.len = ctx->gk5e->keylength;
511 keyout.len = ctx->gk5e->keylength;
512
513 /* initiator seal encryption */
514 set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
515 keyout.data = ctx->initiator_seal;
516 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
517 if (err) {
518 dprintk("%s: Error %d deriving initiator_seal key\n",
519 __func__, err);
520 goto out_err;
521 }
522 ctx->initiator_enc = context_v2_alloc_cipher(ctx,
523 ctx->gk5e->encrypt_name,
524 ctx->initiator_seal);
525 if (ctx->initiator_enc == NULL)
526 goto out_err;
527
528 /* acceptor seal encryption */
529 set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
530 keyout.data = ctx->acceptor_seal;
531 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
532 if (err) {
533 dprintk("%s: Error %d deriving acceptor_seal key\n",
534 __func__, err);
535 goto out_free_initiator_enc;
536 }
537 ctx->acceptor_enc = context_v2_alloc_cipher(ctx,
538 ctx->gk5e->encrypt_name,
539 ctx->acceptor_seal);
540 if (ctx->acceptor_enc == NULL)
541 goto out_free_initiator_enc;
542
543 /* initiator sign checksum */
544 set_cdata(cdata, KG_USAGE_INITIATOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
545 keyout.data = ctx->initiator_sign;
546 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
547 if (err) {
548 dprintk("%s: Error %d deriving initiator_sign key\n",
549 __func__, err);
550 goto out_free_acceptor_enc;
551 }
552
553 /* acceptor sign checksum */
554 set_cdata(cdata, KG_USAGE_ACCEPTOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
555 keyout.data = ctx->acceptor_sign;
556 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
557 if (err) {
558 dprintk("%s: Error %d deriving acceptor_sign key\n",
559 __func__, err);
560 goto out_free_acceptor_enc;
561 }
562
563 /* initiator seal integrity */
564 set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
565 keyout.data = ctx->initiator_integ;
566 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
567 if (err) {
568 dprintk("%s: Error %d deriving initiator_integ key\n",
569 __func__, err);
570 goto out_free_acceptor_enc;
571 }
572
573 /* acceptor seal integrity */
574 set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
575 keyout.data = ctx->acceptor_integ;
576 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
577 if (err) {
578 dprintk("%s: Error %d deriving acceptor_integ key\n",
579 __func__, err);
580 goto out_free_acceptor_enc;
581 }
582
583 switch (ctx->enctype) {
584 case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
585 case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
586 ctx->initiator_enc_aux =
587 context_v2_alloc_cipher(ctx, "cbc(aes)",
588 ctx->initiator_seal);
589 if (ctx->initiator_enc_aux == NULL)
590 goto out_free_acceptor_enc;
591 ctx->acceptor_enc_aux =
592 context_v2_alloc_cipher(ctx, "cbc(aes)",
593 ctx->acceptor_seal);
594 if (ctx->acceptor_enc_aux == NULL) {
595 crypto_free_skcipher(ctx->initiator_enc_aux);
596 goto out_free_acceptor_enc;
597 }
598 }
599
600 return 0;
601
602out_free_acceptor_enc:
603 crypto_free_skcipher(ctx->acceptor_enc);
604out_free_initiator_enc:
605 crypto_free_skcipher(ctx->initiator_enc);
606out_err:
607 return -EINVAL;
608}
609
610static int
611gss_import_v2_context(const void *p, const void *end, struct krb5_ctx *ctx,
612 gfp_t gfp_mask)
613{
614 int keylen;
615
616 p = simple_get_bytes(p, end, &ctx->flags, sizeof(ctx->flags));
617 if (IS_ERR(p))
618 goto out_err;
619 ctx->initiate = ctx->flags & KRB5_CTX_FLAG_INITIATOR;
620
621 p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
622 if (IS_ERR(p))
623 goto out_err;
624 p = simple_get_bytes(p, end, &ctx->seq_send64, sizeof(ctx->seq_send64));
625 if (IS_ERR(p))
626 goto out_err;
627 /* set seq_send for use by "older" enctypes */
628 ctx->seq_send = ctx->seq_send64;
629 if (ctx->seq_send64 != ctx->seq_send) {
630 dprintk("%s: seq_send64 %lx, seq_send %x overflow?\n", __func__,
631 (unsigned long)ctx->seq_send64, ctx->seq_send);
632 p = ERR_PTR(-EINVAL);
633 goto out_err;
634 }
635 p = simple_get_bytes(p, end, &ctx->enctype, sizeof(ctx->enctype));
636 if (IS_ERR(p))
637 goto out_err;
638 /* Map ENCTYPE_DES3_CBC_SHA1 to ENCTYPE_DES3_CBC_RAW */
639 if (ctx->enctype == ENCTYPE_DES3_CBC_SHA1)
640 ctx->enctype = ENCTYPE_DES3_CBC_RAW;
641 ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
642 if (ctx->gk5e == NULL) {
643 dprintk("gss_kerberos_mech: unsupported krb5 enctype %u\n",
644 ctx->enctype);
645 p = ERR_PTR(-EINVAL);
646 goto out_err;
647 }
648 keylen = ctx->gk5e->keylength;
649
650 p = simple_get_bytes(p, end, ctx->Ksess, keylen);
651 if (IS_ERR(p))
652 goto out_err;
653
654 if (p != end) {
655 p = ERR_PTR(-EINVAL);
656 goto out_err;
657 }
658
659 ctx->mech_used.data = kmemdup(gss_kerberos_mech.gm_oid.data,
660 gss_kerberos_mech.gm_oid.len, gfp_mask);
661 if (unlikely(ctx->mech_used.data == NULL)) {
662 p = ERR_PTR(-ENOMEM);
663 goto out_err;
664 }
665 ctx->mech_used.len = gss_kerberos_mech.gm_oid.len;
666
667 switch (ctx->enctype) {
668 case ENCTYPE_DES3_CBC_RAW:
669 return context_derive_keys_des3(ctx, gfp_mask);
670 case ENCTYPE_ARCFOUR_HMAC:
671 return context_derive_keys_rc4(ctx);
672 case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
673 case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
674 return context_derive_keys_new(ctx, gfp_mask);
675 default:
676 return -EINVAL;
677 }
678
679out_err:
680 return PTR_ERR(p);
681}
682
683static int
684gss_import_sec_context_kerberos(const void *p, size_t len,
685 struct gss_ctx *ctx_id,
686 time_t *endtime,
687 gfp_t gfp_mask)
688{
689 const void *end = (const void *)((const char *)p + len);
690 struct krb5_ctx *ctx;
691 int ret;
692
693 ctx = kzalloc(sizeof(*ctx), gfp_mask);
694 if (ctx == NULL)
695 return -ENOMEM;
696
697 if (len == 85)
698 ret = gss_import_v1_context(p, end, ctx);
699 else
700 ret = gss_import_v2_context(p, end, ctx, gfp_mask);
701
702 if (ret == 0) {
703 ctx_id->internal_ctx_id = ctx;
704 if (endtime)
705 *endtime = ctx->endtime;
706 } else
707 kfree(ctx);
708
709 dprintk("RPC: %s: returning %d\n", __func__, ret);
710 return ret;
711}
712
713static void
714gss_delete_sec_context_kerberos(void *internal_ctx) {
715 struct krb5_ctx *kctx = internal_ctx;
716
717 crypto_free_skcipher(kctx->seq);
718 crypto_free_skcipher(kctx->enc);
719 crypto_free_skcipher(kctx->acceptor_enc);
720 crypto_free_skcipher(kctx->initiator_enc);
721 crypto_free_skcipher(kctx->acceptor_enc_aux);
722 crypto_free_skcipher(kctx->initiator_enc_aux);
723 kfree(kctx->mech_used.data);
724 kfree(kctx);
725}
726
727static const struct gss_api_ops gss_kerberos_ops = {
728 .gss_import_sec_context = gss_import_sec_context_kerberos,
729 .gss_get_mic = gss_get_mic_kerberos,
730 .gss_verify_mic = gss_verify_mic_kerberos,
731 .gss_wrap = gss_wrap_kerberos,
732 .gss_unwrap = gss_unwrap_kerberos,
733 .gss_delete_sec_context = gss_delete_sec_context_kerberos,
734};
735
736static struct pf_desc gss_kerberos_pfs[] = {
737 [0] = {
738 .pseudoflavor = RPC_AUTH_GSS_KRB5,
739 .qop = GSS_C_QOP_DEFAULT,
740 .service = RPC_GSS_SVC_NONE,
741 .name = "krb5",
742 },
743 [1] = {
744 .pseudoflavor = RPC_AUTH_GSS_KRB5I,
745 .qop = GSS_C_QOP_DEFAULT,
746 .service = RPC_GSS_SVC_INTEGRITY,
747 .name = "krb5i",
748 },
749 [2] = {
750 .pseudoflavor = RPC_AUTH_GSS_KRB5P,
751 .qop = GSS_C_QOP_DEFAULT,
752 .service = RPC_GSS_SVC_PRIVACY,
753 .name = "krb5p",
754 },
755};
756
757MODULE_ALIAS("rpc-auth-gss-krb5");
758MODULE_ALIAS("rpc-auth-gss-krb5i");
759MODULE_ALIAS("rpc-auth-gss-krb5p");
760MODULE_ALIAS("rpc-auth-gss-390003");
761MODULE_ALIAS("rpc-auth-gss-390004");
762MODULE_ALIAS("rpc-auth-gss-390005");
763MODULE_ALIAS("rpc-auth-gss-1.2.840.113554.1.2.2");
764
765static struct gss_api_mech gss_kerberos_mech = {
766 .gm_name = "krb5",
767 .gm_owner = THIS_MODULE,
768 .gm_oid = { 9, "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02" },
769 .gm_ops = &gss_kerberos_ops,
770 .gm_pf_num = ARRAY_SIZE(gss_kerberos_pfs),
771 .gm_pfs = gss_kerberos_pfs,
772 .gm_upcall_enctypes = KRB5_SUPPORTED_ENCTYPES,
773};
774
775static int __init init_kerberos_module(void)
776{
777 int status;
778
779 status = gss_mech_register(&gss_kerberos_mech);
780 if (status)
781 printk("Failed to register kerberos gss mechanism!\n");
782 return status;
783}
784
785static void __exit cleanup_kerberos_module(void)
786{
787 gss_mech_unregister(&gss_kerberos_mech);
788}
789
790MODULE_LICENSE("GPL");
791module_init(init_kerberos_module);
792module_exit(cleanup_kerberos_module);