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
28 static struct gss_api_mech gss_kerberos_mech; /* forward declaration */
29
30 static 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
144 static const int num_supported_enctypes =
145 ARRAY_SIZE(supported_gss_krb5_enctypes);
146
147 static int
supported_gss_krb5_enctype(int etype)148 supported_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
157 static const struct gss_krb5_enctype *
get_gss_krb5_enctype(int etype)158 get_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
167 static const void *
simple_get_bytes(const void * p,const void * end,void * res,int len)168 simple_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
177 static const void *
simple_get_netobj(const void * p,const void * end,struct xdr_netobj * res)178 simple_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
196 static inline const void *
get_key(const void * p,const void * end,struct krb5_ctx * ctx,struct crypto_sync_skcipher ** res)197 get_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
242 out_err_free_tfm:
243 crypto_free_sync_skcipher(*res);
244 out_err_free_key:
245 kfree(key.data);
246 p = ERR_PTR(-EINVAL);
247 out_err:
248 return p;
249 }
250
251 static int
gss_import_v1_context(const void * p,const void * end,struct krb5_ctx * ctx)252 gss_import_v1_context(const void *p, const void *end, struct krb5_ctx *ctx)
253 {
254 u32 seq_send;
255 int tmp;
256
257 p = simple_get_bytes(p, end, &ctx->initiate, sizeof(ctx->initiate));
258 if (IS_ERR(p))
259 goto out_err;
260
261 /* Old format supports only DES! Any other enctype uses new format */
262 ctx->enctype = ENCTYPE_DES_CBC_RAW;
263
264 ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
265 if (ctx->gk5e == NULL) {
266 p = ERR_PTR(-EINVAL);
267 goto out_err;
268 }
269
270 /* The downcall format was designed before we completely understood
271 * the uses of the context fields; so it includes some stuff we
272 * just give some minimal sanity-checking, and some we ignore
273 * completely (like the next twenty bytes): */
274 if (unlikely(p + 20 > end || p + 20 < p)) {
275 p = ERR_PTR(-EFAULT);
276 goto out_err;
277 }
278 p += 20;
279 p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
280 if (IS_ERR(p))
281 goto out_err;
282 if (tmp != SGN_ALG_DES_MAC_MD5) {
283 p = ERR_PTR(-ENOSYS);
284 goto out_err;
285 }
286 p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
287 if (IS_ERR(p))
288 goto out_err;
289 if (tmp != SEAL_ALG_DES) {
290 p = ERR_PTR(-ENOSYS);
291 goto out_err;
292 }
293 p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
294 if (IS_ERR(p))
295 goto out_err;
296 p = simple_get_bytes(p, end, &seq_send, sizeof(seq_send));
297 if (IS_ERR(p))
298 goto out_err;
299 atomic_set(&ctx->seq_send, seq_send);
300 p = simple_get_netobj(p, end, &ctx->mech_used);
301 if (IS_ERR(p))
302 goto out_err;
303 p = get_key(p, end, ctx, &ctx->enc);
304 if (IS_ERR(p))
305 goto out_err_free_mech;
306 p = get_key(p, end, ctx, &ctx->seq);
307 if (IS_ERR(p))
308 goto out_err_free_key1;
309 if (p != end) {
310 p = ERR_PTR(-EFAULT);
311 goto out_err_free_key2;
312 }
313
314 return 0;
315
316 out_err_free_key2:
317 crypto_free_sync_skcipher(ctx->seq);
318 out_err_free_key1:
319 crypto_free_sync_skcipher(ctx->enc);
320 out_err_free_mech:
321 kfree(ctx->mech_used.data);
322 out_err:
323 return PTR_ERR(p);
324 }
325
326 static struct crypto_sync_skcipher *
context_v2_alloc_cipher(struct krb5_ctx * ctx,const char * cname,u8 * key)327 context_v2_alloc_cipher(struct krb5_ctx *ctx, const char *cname, u8 *key)
328 {
329 struct crypto_sync_skcipher *cp;
330
331 cp = crypto_alloc_sync_skcipher(cname, 0, 0);
332 if (IS_ERR(cp)) {
333 dprintk("gss_kerberos_mech: unable to initialize "
334 "crypto algorithm %s\n", cname);
335 return NULL;
336 }
337 if (crypto_sync_skcipher_setkey(cp, key, ctx->gk5e->keylength)) {
338 dprintk("gss_kerberos_mech: error setting key for "
339 "crypto algorithm %s\n", cname);
340 crypto_free_sync_skcipher(cp);
341 return NULL;
342 }
343 return cp;
344 }
345
346 static inline void
set_cdata(u8 cdata[GSS_KRB5_K5CLENGTH],u32 usage,u8 seed)347 set_cdata(u8 cdata[GSS_KRB5_K5CLENGTH], u32 usage, u8 seed)
348 {
349 cdata[0] = (usage>>24)&0xff;
350 cdata[1] = (usage>>16)&0xff;
351 cdata[2] = (usage>>8)&0xff;
352 cdata[3] = usage&0xff;
353 cdata[4] = seed;
354 }
355
356 static int
context_derive_keys_des3(struct krb5_ctx * ctx,gfp_t gfp_mask)357 context_derive_keys_des3(struct krb5_ctx *ctx, gfp_t gfp_mask)
358 {
359 struct xdr_netobj c, keyin, keyout;
360 u8 cdata[GSS_KRB5_K5CLENGTH];
361 u32 err;
362
363 c.len = GSS_KRB5_K5CLENGTH;
364 c.data = cdata;
365
366 keyin.data = ctx->Ksess;
367 keyin.len = ctx->gk5e->keylength;
368 keyout.len = ctx->gk5e->keylength;
369
370 /* seq uses the raw key */
371 ctx->seq = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
372 ctx->Ksess);
373 if (ctx->seq == NULL)
374 goto out_err;
375
376 ctx->enc = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
377 ctx->Ksess);
378 if (ctx->enc == NULL)
379 goto out_free_seq;
380
381 /* derive cksum */
382 set_cdata(cdata, KG_USAGE_SIGN, KEY_USAGE_SEED_CHECKSUM);
383 keyout.data = ctx->cksum;
384 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
385 if (err) {
386 dprintk("%s: Error %d deriving cksum key\n",
387 __func__, err);
388 goto out_free_enc;
389 }
390
391 return 0;
392
393 out_free_enc:
394 crypto_free_sync_skcipher(ctx->enc);
395 out_free_seq:
396 crypto_free_sync_skcipher(ctx->seq);
397 out_err:
398 return -EINVAL;
399 }
400
401 /*
402 * Note that RC4 depends on deriving keys using the sequence
403 * number or the checksum of a token. Therefore, the final keys
404 * cannot be calculated until the token is being constructed!
405 */
406 static int
context_derive_keys_rc4(struct krb5_ctx * ctx)407 context_derive_keys_rc4(struct krb5_ctx *ctx)
408 {
409 struct crypto_shash *hmac;
410 char sigkeyconstant[] = "signaturekey";
411 int slen = strlen(sigkeyconstant) + 1; /* include null terminator */
412 struct shash_desc *desc;
413 int err;
414
415 dprintk("RPC: %s: entered\n", __func__);
416 /*
417 * derive cksum (aka Ksign) key
418 */
419 hmac = crypto_alloc_shash(ctx->gk5e->cksum_name, 0, 0);
420 if (IS_ERR(hmac)) {
421 dprintk("%s: error %ld allocating hash '%s'\n",
422 __func__, PTR_ERR(hmac), ctx->gk5e->cksum_name);
423 err = PTR_ERR(hmac);
424 goto out_err;
425 }
426
427 err = crypto_shash_setkey(hmac, ctx->Ksess, ctx->gk5e->keylength);
428 if (err)
429 goto out_err_free_hmac;
430
431
432 desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(hmac), GFP_NOFS);
433 if (!desc) {
434 dprintk("%s: failed to allocate hash descriptor for '%s'\n",
435 __func__, ctx->gk5e->cksum_name);
436 err = -ENOMEM;
437 goto out_err_free_hmac;
438 }
439
440 desc->tfm = hmac;
441
442 err = crypto_shash_digest(desc, sigkeyconstant, slen, ctx->cksum);
443 kzfree(desc);
444 if (err)
445 goto out_err_free_hmac;
446 /*
447 * allocate hash, and skciphers for data and seqnum encryption
448 */
449 ctx->enc = crypto_alloc_sync_skcipher(ctx->gk5e->encrypt_name, 0, 0);
450 if (IS_ERR(ctx->enc)) {
451 err = PTR_ERR(ctx->enc);
452 goto out_err_free_hmac;
453 }
454
455 ctx->seq = crypto_alloc_sync_skcipher(ctx->gk5e->encrypt_name, 0, 0);
456 if (IS_ERR(ctx->seq)) {
457 crypto_free_sync_skcipher(ctx->enc);
458 err = PTR_ERR(ctx->seq);
459 goto out_err_free_hmac;
460 }
461
462 dprintk("RPC: %s: returning success\n", __func__);
463
464 err = 0;
465
466 out_err_free_hmac:
467 crypto_free_shash(hmac);
468 out_err:
469 dprintk("RPC: %s: returning %d\n", __func__, err);
470 return err;
471 }
472
473 static int
context_derive_keys_new(struct krb5_ctx * ctx,gfp_t gfp_mask)474 context_derive_keys_new(struct krb5_ctx *ctx, gfp_t gfp_mask)
475 {
476 struct xdr_netobj c, keyin, keyout;
477 u8 cdata[GSS_KRB5_K5CLENGTH];
478 u32 err;
479
480 c.len = GSS_KRB5_K5CLENGTH;
481 c.data = cdata;
482
483 keyin.data = ctx->Ksess;
484 keyin.len = ctx->gk5e->keylength;
485 keyout.len = ctx->gk5e->keylength;
486
487 /* initiator seal encryption */
488 set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
489 keyout.data = ctx->initiator_seal;
490 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
491 if (err) {
492 dprintk("%s: Error %d deriving initiator_seal key\n",
493 __func__, err);
494 goto out_err;
495 }
496 ctx->initiator_enc = context_v2_alloc_cipher(ctx,
497 ctx->gk5e->encrypt_name,
498 ctx->initiator_seal);
499 if (ctx->initiator_enc == NULL)
500 goto out_err;
501
502 /* acceptor seal encryption */
503 set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
504 keyout.data = ctx->acceptor_seal;
505 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
506 if (err) {
507 dprintk("%s: Error %d deriving acceptor_seal key\n",
508 __func__, err);
509 goto out_free_initiator_enc;
510 }
511 ctx->acceptor_enc = context_v2_alloc_cipher(ctx,
512 ctx->gk5e->encrypt_name,
513 ctx->acceptor_seal);
514 if (ctx->acceptor_enc == NULL)
515 goto out_free_initiator_enc;
516
517 /* initiator sign checksum */
518 set_cdata(cdata, KG_USAGE_INITIATOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
519 keyout.data = ctx->initiator_sign;
520 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
521 if (err) {
522 dprintk("%s: Error %d deriving initiator_sign key\n",
523 __func__, err);
524 goto out_free_acceptor_enc;
525 }
526
527 /* acceptor sign checksum */
528 set_cdata(cdata, KG_USAGE_ACCEPTOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
529 keyout.data = ctx->acceptor_sign;
530 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
531 if (err) {
532 dprintk("%s: Error %d deriving acceptor_sign key\n",
533 __func__, err);
534 goto out_free_acceptor_enc;
535 }
536
537 /* initiator seal integrity */
538 set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
539 keyout.data = ctx->initiator_integ;
540 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
541 if (err) {
542 dprintk("%s: Error %d deriving initiator_integ key\n",
543 __func__, err);
544 goto out_free_acceptor_enc;
545 }
546
547 /* acceptor seal integrity */
548 set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
549 keyout.data = ctx->acceptor_integ;
550 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
551 if (err) {
552 dprintk("%s: Error %d deriving acceptor_integ key\n",
553 __func__, err);
554 goto out_free_acceptor_enc;
555 }
556
557 switch (ctx->enctype) {
558 case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
559 case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
560 ctx->initiator_enc_aux =
561 context_v2_alloc_cipher(ctx, "cbc(aes)",
562 ctx->initiator_seal);
563 if (ctx->initiator_enc_aux == NULL)
564 goto out_free_acceptor_enc;
565 ctx->acceptor_enc_aux =
566 context_v2_alloc_cipher(ctx, "cbc(aes)",
567 ctx->acceptor_seal);
568 if (ctx->acceptor_enc_aux == NULL) {
569 crypto_free_sync_skcipher(ctx->initiator_enc_aux);
570 goto out_free_acceptor_enc;
571 }
572 }
573
574 return 0;
575
576 out_free_acceptor_enc:
577 crypto_free_sync_skcipher(ctx->acceptor_enc);
578 out_free_initiator_enc:
579 crypto_free_sync_skcipher(ctx->initiator_enc);
580 out_err:
581 return -EINVAL;
582 }
583
584 static int
gss_import_v2_context(const void * p,const void * end,struct krb5_ctx * ctx,gfp_t gfp_mask)585 gss_import_v2_context(const void *p, const void *end, struct krb5_ctx *ctx,
586 gfp_t gfp_mask)
587 {
588 u64 seq_send64;
589 int keylen;
590
591 p = simple_get_bytes(p, end, &ctx->flags, sizeof(ctx->flags));
592 if (IS_ERR(p))
593 goto out_err;
594 ctx->initiate = ctx->flags & KRB5_CTX_FLAG_INITIATOR;
595
596 p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
597 if (IS_ERR(p))
598 goto out_err;
599 p = simple_get_bytes(p, end, &seq_send64, sizeof(seq_send64));
600 if (IS_ERR(p))
601 goto out_err;
602 atomic64_set(&ctx->seq_send64, seq_send64);
603 /* set seq_send for use by "older" enctypes */
604 atomic_set(&ctx->seq_send, seq_send64);
605 if (seq_send64 != atomic_read(&ctx->seq_send)) {
606 dprintk("%s: seq_send64 %llx, seq_send %x overflow?\n", __func__,
607 seq_send64, atomic_read(&ctx->seq_send));
608 p = ERR_PTR(-EINVAL);
609 goto out_err;
610 }
611 p = simple_get_bytes(p, end, &ctx->enctype, sizeof(ctx->enctype));
612 if (IS_ERR(p))
613 goto out_err;
614 /* Map ENCTYPE_DES3_CBC_SHA1 to ENCTYPE_DES3_CBC_RAW */
615 if (ctx->enctype == ENCTYPE_DES3_CBC_SHA1)
616 ctx->enctype = ENCTYPE_DES3_CBC_RAW;
617 ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
618 if (ctx->gk5e == NULL) {
619 dprintk("gss_kerberos_mech: unsupported krb5 enctype %u\n",
620 ctx->enctype);
621 p = ERR_PTR(-EINVAL);
622 goto out_err;
623 }
624 keylen = ctx->gk5e->keylength;
625
626 p = simple_get_bytes(p, end, ctx->Ksess, keylen);
627 if (IS_ERR(p))
628 goto out_err;
629
630 if (p != end) {
631 p = ERR_PTR(-EINVAL);
632 goto out_err;
633 }
634
635 ctx->mech_used.data = kmemdup(gss_kerberos_mech.gm_oid.data,
636 gss_kerberos_mech.gm_oid.len, gfp_mask);
637 if (unlikely(ctx->mech_used.data == NULL)) {
638 p = ERR_PTR(-ENOMEM);
639 goto out_err;
640 }
641 ctx->mech_used.len = gss_kerberos_mech.gm_oid.len;
642
643 switch (ctx->enctype) {
644 case ENCTYPE_DES3_CBC_RAW:
645 return context_derive_keys_des3(ctx, gfp_mask);
646 case ENCTYPE_ARCFOUR_HMAC:
647 return context_derive_keys_rc4(ctx);
648 case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
649 case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
650 return context_derive_keys_new(ctx, gfp_mask);
651 default:
652 return -EINVAL;
653 }
654
655 out_err:
656 return PTR_ERR(p);
657 }
658
659 static int
gss_import_sec_context_kerberos(const void * p,size_t len,struct gss_ctx * ctx_id,time_t * endtime,gfp_t gfp_mask)660 gss_import_sec_context_kerberos(const void *p, size_t len,
661 struct gss_ctx *ctx_id,
662 time_t *endtime,
663 gfp_t gfp_mask)
664 {
665 const void *end = (const void *)((const char *)p + len);
666 struct krb5_ctx *ctx;
667 int ret;
668
669 ctx = kzalloc(sizeof(*ctx), gfp_mask);
670 if (ctx == NULL)
671 return -ENOMEM;
672
673 if (len == 85)
674 ret = gss_import_v1_context(p, end, ctx);
675 else
676 ret = gss_import_v2_context(p, end, ctx, gfp_mask);
677
678 if (ret == 0) {
679 ctx_id->internal_ctx_id = ctx;
680 if (endtime)
681 *endtime = ctx->endtime;
682 } else
683 kfree(ctx);
684
685 dprintk("RPC: %s: returning %d\n", __func__, ret);
686 return ret;
687 }
688
689 static void
gss_delete_sec_context_kerberos(void * internal_ctx)690 gss_delete_sec_context_kerberos(void *internal_ctx) {
691 struct krb5_ctx *kctx = internal_ctx;
692
693 crypto_free_sync_skcipher(kctx->seq);
694 crypto_free_sync_skcipher(kctx->enc);
695 crypto_free_sync_skcipher(kctx->acceptor_enc);
696 crypto_free_sync_skcipher(kctx->initiator_enc);
697 crypto_free_sync_skcipher(kctx->acceptor_enc_aux);
698 crypto_free_sync_skcipher(kctx->initiator_enc_aux);
699 kfree(kctx->mech_used.data);
700 kfree(kctx);
701 }
702
703 static const struct gss_api_ops gss_kerberos_ops = {
704 .gss_import_sec_context = gss_import_sec_context_kerberos,
705 .gss_get_mic = gss_get_mic_kerberos,
706 .gss_verify_mic = gss_verify_mic_kerberos,
707 .gss_wrap = gss_wrap_kerberos,
708 .gss_unwrap = gss_unwrap_kerberos,
709 .gss_delete_sec_context = gss_delete_sec_context_kerberos,
710 };
711
712 static struct pf_desc gss_kerberos_pfs[] = {
713 [0] = {
714 .pseudoflavor = RPC_AUTH_GSS_KRB5,
715 .qop = GSS_C_QOP_DEFAULT,
716 .service = RPC_GSS_SVC_NONE,
717 .name = "krb5",
718 },
719 [1] = {
720 .pseudoflavor = RPC_AUTH_GSS_KRB5I,
721 .qop = GSS_C_QOP_DEFAULT,
722 .service = RPC_GSS_SVC_INTEGRITY,
723 .name = "krb5i",
724 .datatouch = true,
725 },
726 [2] = {
727 .pseudoflavor = RPC_AUTH_GSS_KRB5P,
728 .qop = GSS_C_QOP_DEFAULT,
729 .service = RPC_GSS_SVC_PRIVACY,
730 .name = "krb5p",
731 .datatouch = true,
732 },
733 };
734
735 MODULE_ALIAS("rpc-auth-gss-krb5");
736 MODULE_ALIAS("rpc-auth-gss-krb5i");
737 MODULE_ALIAS("rpc-auth-gss-krb5p");
738 MODULE_ALIAS("rpc-auth-gss-390003");
739 MODULE_ALIAS("rpc-auth-gss-390004");
740 MODULE_ALIAS("rpc-auth-gss-390005");
741 MODULE_ALIAS("rpc-auth-gss-1.2.840.113554.1.2.2");
742
743 static struct gss_api_mech gss_kerberos_mech = {
744 .gm_name = "krb5",
745 .gm_owner = THIS_MODULE,
746 .gm_oid = { 9, "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02" },
747 .gm_ops = &gss_kerberos_ops,
748 .gm_pf_num = ARRAY_SIZE(gss_kerberos_pfs),
749 .gm_pfs = gss_kerberos_pfs,
750 .gm_upcall_enctypes = KRB5_SUPPORTED_ENCTYPES,
751 };
752
init_kerberos_module(void)753 static int __init init_kerberos_module(void)
754 {
755 int status;
756
757 status = gss_mech_register(&gss_kerberos_mech);
758 if (status)
759 printk("Failed to register kerberos gss mechanism!\n");
760 return status;
761 }
762
cleanup_kerberos_module(void)763 static void __exit cleanup_kerberos_module(void)
764 {
765 gss_mech_unregister(&gss_kerberos_mech);
766 }
767
768 MODULE_LICENSE("GPL");
769 module_init(init_kerberos_module);
770 module_exit(cleanup_kerberos_module);
771