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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;
31
32static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
33#ifndef CONFIG_SUNRPC_DISABLE_INSECURE_ENCTYPES
34
35
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
56
57
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
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
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
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
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
224
225
226
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
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
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
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
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
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
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
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
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
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
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
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
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);
655
