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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#include "auth_gss_internal.h"
25
26#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
27# define RPCDBG_FACILITY RPCDBG_AUTH
28#endif
29
30static struct gss_api_mech gss_kerberos_mech; /* forward declaration */
31
32static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
33#ifndef CONFIG_SUNRPC_DISABLE_INSECURE_ENCTYPES
34 /*
35 * DES (All DES enctypes are mapped to the same gss functionality)
36 */
37 {
38 .etype = ENCTYPE_DES_CBC_RAW,
39 .ctype = CKSUMTYPE_RSA_MD5,
40 .name = "des-cbc-crc",
41 .encrypt_name = "cbc(des)",
42 .cksum_name = "md5",
43 .encrypt = krb5_encrypt,
44 .decrypt = krb5_decrypt,
45 .mk_key = NULL,
46 .signalg = SGN_ALG_DES_MAC_MD5,
47 .sealalg = SEAL_ALG_DES,
48 .keybytes = 7,
49 .keylength = 8,
50 .blocksize = 8,
51 .conflen = 8,
52 .cksumlength = 8,
53 .keyed_cksum = 0,
54 },
55#endif /* CONFIG_SUNRPC_DISABLE_INSECURE_ENCTYPES */
56 /*
57 * 3DES
58 */
59 {
60 .etype = ENCTYPE_DES3_CBC_RAW,
61 .ctype = CKSUMTYPE_HMAC_SHA1_DES3,
62 .name = "des3-hmac-sha1",
63 .encrypt_name = "cbc(des3_ede)",
64 .cksum_name = "hmac(sha1)",
65 .encrypt = krb5_encrypt,
66 .decrypt = krb5_decrypt,
67 .mk_key = gss_krb5_des3_make_key,
68 .signalg = SGN_ALG_HMAC_SHA1_DES3_KD,
69 .sealalg = SEAL_ALG_DES3KD,
70 .keybytes = 21,
71 .keylength = 24,
72 .blocksize = 8,
73 .conflen = 8,
74 .cksumlength = 20,
75 .keyed_cksum = 1,
76 },
77 /*
78 * AES128
79 */
80 {
81 .etype = ENCTYPE_AES128_CTS_HMAC_SHA1_96,
82 .ctype = CKSUMTYPE_HMAC_SHA1_96_AES128,
83 .name = "aes128-cts",
84 .encrypt_name = "cts(cbc(aes))",
85 .cksum_name = "hmac(sha1)",
86 .encrypt = krb5_encrypt,
87 .decrypt = krb5_decrypt,
88 .mk_key = gss_krb5_aes_make_key,
89 .encrypt_v2 = gss_krb5_aes_encrypt,
90 .decrypt_v2 = gss_krb5_aes_decrypt,
91 .signalg = -1,
92 .sealalg = -1,
93 .keybytes = 16,
94 .keylength = 16,
95 .blocksize = 16,
96 .conflen = 16,
97 .cksumlength = 12,
98 .keyed_cksum = 1,
99 },
100 /*
101 * AES256
102 */
103 {
104 .etype = ENCTYPE_AES256_CTS_HMAC_SHA1_96,
105 .ctype = CKSUMTYPE_HMAC_SHA1_96_AES256,
106 .name = "aes256-cts",
107 .encrypt_name = "cts(cbc(aes))",
108 .cksum_name = "hmac(sha1)",
109 .encrypt = krb5_encrypt,
110 .decrypt = krb5_decrypt,
111 .mk_key = gss_krb5_aes_make_key,
112 .encrypt_v2 = gss_krb5_aes_encrypt,
113 .decrypt_v2 = gss_krb5_aes_decrypt,
114 .signalg = -1,
115 .sealalg = -1,
116 .keybytes = 32,
117 .keylength = 32,
118 .blocksize = 16,
119 .conflen = 16,
120 .cksumlength = 12,
121 .keyed_cksum = 1,
122 },
123};
124
125static const int num_supported_enctypes =
126 ARRAY_SIZE(supported_gss_krb5_enctypes);
127
128static int
129supported_gss_krb5_enctype(int etype)
130{
131 int i;
132 for (i = 0; i < num_supported_enctypes; i++)
133 if (supported_gss_krb5_enctypes[i].etype == etype)
134 return 1;
135 return 0;
136}
137
138static const struct gss_krb5_enctype *
139get_gss_krb5_enctype(int etype)
140{
141 int i;
142 for (i = 0; i < num_supported_enctypes; i++)
143 if (supported_gss_krb5_enctypes[i].etype == etype)
144 return &supported_gss_krb5_enctypes[i];
145 return NULL;
146}
147
148static inline const void *
149get_key(const void *p, const void *end,
150 struct krb5_ctx *ctx, struct crypto_sync_skcipher **res)
151{
152 struct xdr_netobj key;
153 int alg;
154
155 p = simple_get_bytes(p, end, &alg, sizeof(alg));
156 if (IS_ERR(p))
157 goto out_err;
158
159 switch (alg) {
160 case ENCTYPE_DES_CBC_CRC:
161 case ENCTYPE_DES_CBC_MD4:
162 case ENCTYPE_DES_CBC_MD5:
163 /* Map all these key types to ENCTYPE_DES_CBC_RAW */
164 alg = ENCTYPE_DES_CBC_RAW;
165 break;
166 }
167
168 if (!supported_gss_krb5_enctype(alg)) {
169 printk(KERN_WARNING "gss_kerberos_mech: unsupported "
170 "encryption key algorithm %d\n", alg);
171 p = ERR_PTR(-EINVAL);
172 goto out_err;
173 }
174 p = simple_get_netobj(p, end, &key);
175 if (IS_ERR(p))
176 goto out_err;
177
178 *res = crypto_alloc_sync_skcipher(ctx->gk5e->encrypt_name, 0, 0);
179 if (IS_ERR(*res)) {
180 printk(KERN_WARNING "gss_kerberos_mech: unable to initialize "
181 "crypto algorithm %s\n", ctx->gk5e->encrypt_name);
182 *res = NULL;
183 goto out_err_free_key;
184 }
185 if (crypto_sync_skcipher_setkey(*res, key.data, key.len)) {
186 printk(KERN_WARNING "gss_kerberos_mech: error setting key for "
187 "crypto algorithm %s\n", ctx->gk5e->encrypt_name);
188 goto out_err_free_tfm;
189 }
190
191 kfree(key.data);
192 return p;
193
194out_err_free_tfm:
195 crypto_free_sync_skcipher(*res);
196out_err_free_key:
197 kfree(key.data);
198 p = ERR_PTR(-EINVAL);
199out_err:
200 return p;
201}
202
203static int
204gss_import_v1_context(const void *p, const void *end, struct krb5_ctx *ctx)
205{
206 u32 seq_send;
207 int tmp;
208 u32 time32;
209
210 p = simple_get_bytes(p, end, &ctx->initiate, sizeof(ctx->initiate));
211 if (IS_ERR(p))
212 goto out_err;
213
214 /* Old format supports only DES! Any other enctype uses new format */
215 ctx->enctype = ENCTYPE_DES_CBC_RAW;
216
217 ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
218 if (ctx->gk5e == NULL) {
219 p = ERR_PTR(-EINVAL);
220 goto out_err;
221 }
222
223 /* The downcall format was designed before we completely understood
224 * the uses of the context fields; so it includes some stuff we
225 * just give some minimal sanity-checking, and some we ignore
226 * completely (like the next twenty bytes): */
227 if (unlikely(p + 20 > end || p + 20 < p)) {
228 p = ERR_PTR(-EFAULT);
229 goto out_err;
230 }
231 p += 20;
232 p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
233 if (IS_ERR(p))
234 goto out_err;
235 if (tmp != SGN_ALG_DES_MAC_MD5) {
236 p = ERR_PTR(-ENOSYS);
237 goto out_err;
238 }
239 p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
240 if (IS_ERR(p))
241 goto out_err;
242 if (tmp != SEAL_ALG_DES) {
243 p = ERR_PTR(-ENOSYS);
244 goto out_err;
245 }
246 p = simple_get_bytes(p, end, &time32, sizeof(time32));
247 if (IS_ERR(p))
248 goto out_err;
249 /* unsigned 32-bit time overflows in year 2106 */
250 ctx->endtime = (time64_t)time32;
251 p = simple_get_bytes(p, end, &seq_send, sizeof(seq_send));
252 if (IS_ERR(p))
253 goto out_err;
254 atomic_set(&ctx->seq_send, seq_send);
255 p = simple_get_netobj(p, end, &ctx->mech_used);
256 if (IS_ERR(p))
257 goto out_err;
258 p = get_key(p, end, ctx, &ctx->enc);
259 if (IS_ERR(p))
260 goto out_err_free_mech;
261 p = get_key(p, end, ctx, &ctx->seq);
262 if (IS_ERR(p))
263 goto out_err_free_key1;
264 if (p != end) {
265 p = ERR_PTR(-EFAULT);
266 goto out_err_free_key2;
267 }
268
269 return 0;
270
271out_err_free_key2:
272 crypto_free_sync_skcipher(ctx->seq);
273out_err_free_key1:
274 crypto_free_sync_skcipher(ctx->enc);
275out_err_free_mech:
276 kfree(ctx->mech_used.data);
277out_err:
278 return PTR_ERR(p);
279}
280
281static struct crypto_sync_skcipher *
282context_v2_alloc_cipher(struct krb5_ctx *ctx, const char *cname, u8 *key)
283{
284 struct crypto_sync_skcipher *cp;
285
286 cp = crypto_alloc_sync_skcipher(cname, 0, 0);
287 if (IS_ERR(cp)) {
288 dprintk("gss_kerberos_mech: unable to initialize "
289 "crypto algorithm %s\n", cname);
290 return NULL;
291 }
292 if (crypto_sync_skcipher_setkey(cp, key, ctx->gk5e->keylength)) {
293 dprintk("gss_kerberos_mech: error setting key for "
294 "crypto algorithm %s\n", cname);
295 crypto_free_sync_skcipher(cp);
296 return NULL;
297 }
298 return cp;
299}
300
301static inline void
302set_cdata(u8 cdata[GSS_KRB5_K5CLENGTH], u32 usage, u8 seed)
303{
304 cdata[0] = (usage>>24)&0xff;
305 cdata[1] = (usage>>16)&0xff;
306 cdata[2] = (usage>>8)&0xff;
307 cdata[3] = usage&0xff;
308 cdata[4] = seed;
309}
310
311static int
312context_derive_keys_des3(struct krb5_ctx *ctx, gfp_t gfp_mask)
313{
314 struct xdr_netobj c, keyin, keyout;
315 u8 cdata[GSS_KRB5_K5CLENGTH];
316 u32 err;
317
318 c.len = GSS_KRB5_K5CLENGTH;
319 c.data = cdata;
320
321 keyin.data = ctx->Ksess;
322 keyin.len = ctx->gk5e->keylength;
323 keyout.len = ctx->gk5e->keylength;
324
325 /* seq uses the raw key */
326 ctx->seq = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
327 ctx->Ksess);
328 if (ctx->seq == NULL)
329 goto out_err;
330
331 ctx->enc = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
332 ctx->Ksess);
333 if (ctx->enc == NULL)
334 goto out_free_seq;
335
336 /* derive cksum */
337 set_cdata(cdata, KG_USAGE_SIGN, KEY_USAGE_SEED_CHECKSUM);
338 keyout.data = ctx->cksum;
339 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
340 if (err) {
341 dprintk("%s: Error %d deriving cksum key\n",
342 __func__, err);
343 goto out_free_enc;
344 }
345
346 return 0;
347
348out_free_enc:
349 crypto_free_sync_skcipher(ctx->enc);
350out_free_seq:
351 crypto_free_sync_skcipher(ctx->seq);
352out_err:
353 return -EINVAL;
354}
355
356static int
357context_derive_keys_new(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 /* initiator seal encryption */
371 set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
372 keyout.data = ctx->initiator_seal;
373 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
374 if (err) {
375 dprintk("%s: Error %d deriving initiator_seal key\n",
376 __func__, err);
377 goto out_err;
378 }
379 ctx->initiator_enc = context_v2_alloc_cipher(ctx,
380 ctx->gk5e->encrypt_name,
381 ctx->initiator_seal);
382 if (ctx->initiator_enc == NULL)
383 goto out_err;
384
385 /* acceptor seal encryption */
386 set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
387 keyout.data = ctx->acceptor_seal;
388 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
389 if (err) {
390 dprintk("%s: Error %d deriving acceptor_seal key\n",
391 __func__, err);
392 goto out_free_initiator_enc;
393 }
394 ctx->acceptor_enc = context_v2_alloc_cipher(ctx,
395 ctx->gk5e->encrypt_name,
396 ctx->acceptor_seal);
397 if (ctx->acceptor_enc == NULL)
398 goto out_free_initiator_enc;
399
400 /* initiator sign checksum */
401 set_cdata(cdata, KG_USAGE_INITIATOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
402 keyout.data = ctx->initiator_sign;
403 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
404 if (err) {
405 dprintk("%s: Error %d deriving initiator_sign key\n",
406 __func__, err);
407 goto out_free_acceptor_enc;
408 }
409
410 /* acceptor sign checksum */
411 set_cdata(cdata, KG_USAGE_ACCEPTOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
412 keyout.data = ctx->acceptor_sign;
413 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
414 if (err) {
415 dprintk("%s: Error %d deriving acceptor_sign key\n",
416 __func__, err);
417 goto out_free_acceptor_enc;
418 }
419
420 /* initiator seal integrity */
421 set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
422 keyout.data = ctx->initiator_integ;
423 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
424 if (err) {
425 dprintk("%s: Error %d deriving initiator_integ key\n",
426 __func__, err);
427 goto out_free_acceptor_enc;
428 }
429
430 /* acceptor seal integrity */
431 set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
432 keyout.data = ctx->acceptor_integ;
433 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
434 if (err) {
435 dprintk("%s: Error %d deriving acceptor_integ key\n",
436 __func__, err);
437 goto out_free_acceptor_enc;
438 }
439
440 switch (ctx->enctype) {
441 case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
442 case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
443 ctx->initiator_enc_aux =
444 context_v2_alloc_cipher(ctx, "cbc(aes)",
445 ctx->initiator_seal);
446 if (ctx->initiator_enc_aux == NULL)
447 goto out_free_acceptor_enc;
448 ctx->acceptor_enc_aux =
449 context_v2_alloc_cipher(ctx, "cbc(aes)",
450 ctx->acceptor_seal);
451 if (ctx->acceptor_enc_aux == NULL) {
452 crypto_free_sync_skcipher(ctx->initiator_enc_aux);
453 goto out_free_acceptor_enc;
454 }
455 }
456
457 return 0;
458
459out_free_acceptor_enc:
460 crypto_free_sync_skcipher(ctx->acceptor_enc);
461out_free_initiator_enc:
462 crypto_free_sync_skcipher(ctx->initiator_enc);
463out_err:
464 return -EINVAL;
465}
466
467static int
468gss_import_v2_context(const void *p, const void *end, struct krb5_ctx *ctx,
469 gfp_t gfp_mask)
470{
471 u64 seq_send64;
472 int keylen;
473 u32 time32;
474
475 p = simple_get_bytes(p, end, &ctx->flags, sizeof(ctx->flags));
476 if (IS_ERR(p))
477 goto out_err;
478 ctx->initiate = ctx->flags & KRB5_CTX_FLAG_INITIATOR;
479
480 p = simple_get_bytes(p, end, &time32, sizeof(time32));
481 if (IS_ERR(p))
482 goto out_err;
483 /* unsigned 32-bit time overflows in year 2106 */
484 ctx->endtime = (time64_t)time32;
485 p = simple_get_bytes(p, end, &seq_send64, sizeof(seq_send64));
486 if (IS_ERR(p))
487 goto out_err;
488 atomic64_set(&ctx->seq_send64, seq_send64);
489 /* set seq_send for use by "older" enctypes */
490 atomic_set(&ctx->seq_send, seq_send64);
491 if (seq_send64 != atomic_read(&ctx->seq_send)) {
492 dprintk("%s: seq_send64 %llx, seq_send %x overflow?\n", __func__,
493 seq_send64, atomic_read(&ctx->seq_send));
494 p = ERR_PTR(-EINVAL);
495 goto out_err;
496 }
497 p = simple_get_bytes(p, end, &ctx->enctype, sizeof(ctx->enctype));
498 if (IS_ERR(p))
499 goto out_err;
500 /* Map ENCTYPE_DES3_CBC_SHA1 to ENCTYPE_DES3_CBC_RAW */
501 if (ctx->enctype == ENCTYPE_DES3_CBC_SHA1)
502 ctx->enctype = ENCTYPE_DES3_CBC_RAW;
503 ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
504 if (ctx->gk5e == NULL) {
505 dprintk("gss_kerberos_mech: unsupported krb5 enctype %u\n",
506 ctx->enctype);
507 p = ERR_PTR(-EINVAL);
508 goto out_err;
509 }
510 keylen = ctx->gk5e->keylength;
511
512 p = simple_get_bytes(p, end, ctx->Ksess, keylen);
513 if (IS_ERR(p))
514 goto out_err;
515
516 if (p != end) {
517 p = ERR_PTR(-EINVAL);
518 goto out_err;
519 }
520
521 ctx->mech_used.data = kmemdup(gss_kerberos_mech.gm_oid.data,
522 gss_kerberos_mech.gm_oid.len, gfp_mask);
523 if (unlikely(ctx->mech_used.data == NULL)) {
524 p = ERR_PTR(-ENOMEM);
525 goto out_err;
526 }
527 ctx->mech_used.len = gss_kerberos_mech.gm_oid.len;
528
529 switch (ctx->enctype) {
530 case ENCTYPE_DES3_CBC_RAW:
531 return context_derive_keys_des3(ctx, gfp_mask);
532 case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
533 case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
534 return context_derive_keys_new(ctx, gfp_mask);
535 default:
536 return -EINVAL;
537 }
538
539out_err:
540 return PTR_ERR(p);
541}
542
543static int
544gss_import_sec_context_kerberos(const void *p, size_t len,
545 struct gss_ctx *ctx_id,
546 time64_t *endtime,
547 gfp_t gfp_mask)
548{
549 const void *end = (const void *)((const char *)p + len);
550 struct krb5_ctx *ctx;
551 int ret;
552
553 ctx = kzalloc(sizeof(*ctx), gfp_mask);
554 if (ctx == NULL)
555 return -ENOMEM;
556
557 if (len == 85)
558 ret = gss_import_v1_context(p, end, ctx);
559 else
560 ret = gss_import_v2_context(p, end, ctx, gfp_mask);
561
562 if (ret == 0) {
563 ctx_id->internal_ctx_id = ctx;
564 if (endtime)
565 *endtime = ctx->endtime;
566 } else
567 kfree(ctx);
568
569 dprintk("RPC: %s: returning %d\n", __func__, ret);
570 return ret;
571}
572
573static void
574gss_delete_sec_context_kerberos(void *internal_ctx) {
575 struct krb5_ctx *kctx = internal_ctx;
576
577 crypto_free_sync_skcipher(kctx->seq);
578 crypto_free_sync_skcipher(kctx->enc);
579 crypto_free_sync_skcipher(kctx->acceptor_enc);
580 crypto_free_sync_skcipher(kctx->initiator_enc);
581 crypto_free_sync_skcipher(kctx->acceptor_enc_aux);
582 crypto_free_sync_skcipher(kctx->initiator_enc_aux);
583 kfree(kctx->mech_used.data);
584 kfree(kctx);
585}
586
587static const struct gss_api_ops gss_kerberos_ops = {
588 .gss_import_sec_context = gss_import_sec_context_kerberos,
589 .gss_get_mic = gss_get_mic_kerberos,
590 .gss_verify_mic = gss_verify_mic_kerberos,
591 .gss_wrap = gss_wrap_kerberos,
592 .gss_unwrap = gss_unwrap_kerberos,
593 .gss_delete_sec_context = gss_delete_sec_context_kerberos,
594};
595
596static struct pf_desc gss_kerberos_pfs[] = {
597 [0] = {
598 .pseudoflavor = RPC_AUTH_GSS_KRB5,
599 .qop = GSS_C_QOP_DEFAULT,
600 .service = RPC_GSS_SVC_NONE,
601 .name = "krb5",
602 },
603 [1] = {
604 .pseudoflavor = RPC_AUTH_GSS_KRB5I,
605 .qop = GSS_C_QOP_DEFAULT,
606 .service = RPC_GSS_SVC_INTEGRITY,
607 .name = "krb5i",
608 .datatouch = true,
609 },
610 [2] = {
611 .pseudoflavor = RPC_AUTH_GSS_KRB5P,
612 .qop = GSS_C_QOP_DEFAULT,
613 .service = RPC_GSS_SVC_PRIVACY,
614 .name = "krb5p",
615 .datatouch = true,
616 },
617};
618
619MODULE_ALIAS("rpc-auth-gss-krb5");
620MODULE_ALIAS("rpc-auth-gss-krb5i");
621MODULE_ALIAS("rpc-auth-gss-krb5p");
622MODULE_ALIAS("rpc-auth-gss-390003");
623MODULE_ALIAS("rpc-auth-gss-390004");
624MODULE_ALIAS("rpc-auth-gss-390005");
625MODULE_ALIAS("rpc-auth-gss-1.2.840.113554.1.2.2");
626
627static struct gss_api_mech gss_kerberos_mech = {
628 .gm_name = "krb5",
629 .gm_owner = THIS_MODULE,
630 .gm_oid = { 9, "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02" },
631 .gm_ops = &gss_kerberos_ops,
632 .gm_pf_num = ARRAY_SIZE(gss_kerberos_pfs),
633 .gm_pfs = gss_kerberos_pfs,
634 .gm_upcall_enctypes = KRB5_SUPPORTED_ENCTYPES,
635};
636
637static int __init init_kerberos_module(void)
638{
639 int status;
640
641 status = gss_mech_register(&gss_kerberos_mech);
642 if (status)
643 printk("Failed to register kerberos gss mechanism!\n");
644 return status;
645}
646
647static void __exit cleanup_kerberos_module(void)
648{
649 gss_mech_unregister(&gss_kerberos_mech);
650}
651
652MODULE_LICENSE("GPL");
653module_init(init_kerberos_module);
654module_exit(cleanup_kerberos_module);
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);