2 * linux/net/sunrpc/gss_krb5_mech.c
4 * Copyright (c) 2001-2008 The Regents of the University of Michigan.
7 * Andy Adamson <andros@umich.edu>
8 * J. Bruce Fields <bfields@umich.edu>
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
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.
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.
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>
49 #include "auth_gss_internal.h"
51 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
52 # define RPCDBG_FACILITY RPCDBG_AUTH
55 static struct gss_api_mech gss_kerberos_mech; /* forward declaration */
57 static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
59 * DES (All DES enctypes are mapped to the same gss functionality)
62 .etype = ENCTYPE_DES_CBC_RAW,
63 .ctype = CKSUMTYPE_RSA_MD5,
64 .name = "des-cbc-crc",
65 .encrypt_name = "cbc(des)",
67 .encrypt = krb5_encrypt,
68 .decrypt = krb5_decrypt,
70 .signalg = SGN_ALG_DES_MAC_MD5,
71 .sealalg = SEAL_ALG_DES,
83 .etype = ENCTYPE_ARCFOUR_HMAC,
84 .ctype = CKSUMTYPE_HMAC_MD5_ARCFOUR,
86 .encrypt_name = "ecb(arc4)",
87 .cksum_name = "hmac(md5)",
88 .encrypt = krb5_encrypt,
89 .decrypt = krb5_decrypt,
91 .signalg = SGN_ALG_HMAC_MD5,
92 .sealalg = SEAL_ALG_MICROSOFT_RC4,
104 .etype = ENCTYPE_DES3_CBC_RAW,
105 .ctype = CKSUMTYPE_HMAC_SHA1_DES3,
106 .name = "des3-hmac-sha1",
107 .encrypt_name = "cbc(des3_ede)",
108 .cksum_name = "hmac(sha1)",
109 .encrypt = krb5_encrypt,
110 .decrypt = krb5_decrypt,
111 .mk_key = gss_krb5_des3_make_key,
112 .signalg = SGN_ALG_HMAC_SHA1_DES3_KD,
113 .sealalg = SEAL_ALG_DES3KD,
125 .etype = ENCTYPE_AES128_CTS_HMAC_SHA1_96,
126 .ctype = CKSUMTYPE_HMAC_SHA1_96_AES128,
127 .name = "aes128-cts",
128 .encrypt_name = "cts(cbc(aes))",
129 .cksum_name = "hmac(sha1)",
130 .encrypt = krb5_encrypt,
131 .decrypt = krb5_decrypt,
132 .mk_key = gss_krb5_aes_make_key,
133 .encrypt_v2 = gss_krb5_aes_encrypt,
134 .decrypt_v2 = gss_krb5_aes_decrypt,
148 .etype = ENCTYPE_AES256_CTS_HMAC_SHA1_96,
149 .ctype = CKSUMTYPE_HMAC_SHA1_96_AES256,
150 .name = "aes256-cts",
151 .encrypt_name = "cts(cbc(aes))",
152 .cksum_name = "hmac(sha1)",
153 .encrypt = krb5_encrypt,
154 .decrypt = krb5_decrypt,
155 .mk_key = gss_krb5_aes_make_key,
156 .encrypt_v2 = gss_krb5_aes_encrypt,
157 .decrypt_v2 = gss_krb5_aes_decrypt,
169 static const int num_supported_enctypes =
170 ARRAY_SIZE(supported_gss_krb5_enctypes);
173 supported_gss_krb5_enctype(int etype)
176 for (i = 0; i < num_supported_enctypes; i++)
177 if (supported_gss_krb5_enctypes[i].etype == etype)
182 static const struct gss_krb5_enctype *
183 get_gss_krb5_enctype(int etype)
186 for (i = 0; i < num_supported_enctypes; i++)
187 if (supported_gss_krb5_enctypes[i].etype == etype)
188 return &supported_gss_krb5_enctypes[i];
192 static inline const void *
193 get_key(const void *p, const void *end,
194 struct krb5_ctx *ctx, struct crypto_skcipher **res)
196 struct xdr_netobj key;
199 p = simple_get_bytes(p, end, &alg, sizeof(alg));
204 case ENCTYPE_DES_CBC_CRC:
205 case ENCTYPE_DES_CBC_MD4:
206 case ENCTYPE_DES_CBC_MD5:
207 /* Map all these key types to ENCTYPE_DES_CBC_RAW */
208 alg = ENCTYPE_DES_CBC_RAW;
212 if (!supported_gss_krb5_enctype(alg)) {
213 printk(KERN_WARNING "gss_kerberos_mech: unsupported "
214 "encryption key algorithm %d\n", alg);
215 p = ERR_PTR(-EINVAL);
218 p = simple_get_netobj(p, end, &key);
222 *res = crypto_alloc_skcipher(ctx->gk5e->encrypt_name, 0,
225 printk(KERN_WARNING "gss_kerberos_mech: unable to initialize "
226 "crypto algorithm %s\n", ctx->gk5e->encrypt_name);
228 goto out_err_free_key;
230 if (crypto_skcipher_setkey(*res, key.data, key.len)) {
231 printk(KERN_WARNING "gss_kerberos_mech: error setting key for "
232 "crypto algorithm %s\n", ctx->gk5e->encrypt_name);
233 goto out_err_free_tfm;
240 crypto_free_skcipher(*res);
243 p = ERR_PTR(-EINVAL);
249 gss_import_v1_context(const void *p, const void *end, struct krb5_ctx *ctx)
253 p = simple_get_bytes(p, end, &ctx->initiate, sizeof(ctx->initiate));
257 /* Old format supports only DES! Any other enctype uses new format */
258 ctx->enctype = ENCTYPE_DES_CBC_RAW;
260 ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
261 if (ctx->gk5e == NULL) {
262 p = ERR_PTR(-EINVAL);
266 /* The downcall format was designed before we completely understood
267 * the uses of the context fields; so it includes some stuff we
268 * just give some minimal sanity-checking, and some we ignore
269 * completely (like the next twenty bytes): */
270 if (unlikely(p + 20 > end || p + 20 < p)) {
271 p = ERR_PTR(-EFAULT);
275 p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
278 if (tmp != SGN_ALG_DES_MAC_MD5) {
279 p = ERR_PTR(-ENOSYS);
282 p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
285 if (tmp != SEAL_ALG_DES) {
286 p = ERR_PTR(-ENOSYS);
289 p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
292 p = simple_get_bytes(p, end, &ctx->seq_send, sizeof(ctx->seq_send));
295 p = simple_get_netobj(p, end, &ctx->mech_used);
298 p = get_key(p, end, ctx, &ctx->enc);
300 goto out_err_free_mech;
301 p = get_key(p, end, ctx, &ctx->seq);
303 goto out_err_free_key1;
305 p = ERR_PTR(-EFAULT);
306 goto out_err_free_key2;
312 crypto_free_skcipher(ctx->seq);
314 crypto_free_skcipher(ctx->enc);
316 kfree(ctx->mech_used.data);
321 static struct crypto_skcipher *
322 context_v2_alloc_cipher(struct krb5_ctx *ctx, const char *cname, u8 *key)
324 struct crypto_skcipher *cp;
326 cp = crypto_alloc_skcipher(cname, 0, CRYPTO_ALG_ASYNC);
328 dprintk("gss_kerberos_mech: unable to initialize "
329 "crypto algorithm %s\n", cname);
332 if (crypto_skcipher_setkey(cp, key, ctx->gk5e->keylength)) {
333 dprintk("gss_kerberos_mech: error setting key for "
334 "crypto algorithm %s\n", cname);
335 crypto_free_skcipher(cp);
342 set_cdata(u8 cdata[GSS_KRB5_K5CLENGTH], u32 usage, u8 seed)
344 cdata[0] = (usage>>24)&0xff;
345 cdata[1] = (usage>>16)&0xff;
346 cdata[2] = (usage>>8)&0xff;
347 cdata[3] = usage&0xff;
352 context_derive_keys_des3(struct krb5_ctx *ctx, gfp_t gfp_mask)
354 struct xdr_netobj c, keyin, keyout;
355 u8 cdata[GSS_KRB5_K5CLENGTH];
358 c.len = GSS_KRB5_K5CLENGTH;
361 keyin.data = ctx->Ksess;
362 keyin.len = ctx->gk5e->keylength;
363 keyout.len = ctx->gk5e->keylength;
365 /* seq uses the raw key */
366 ctx->seq = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
368 if (ctx->seq == NULL)
371 ctx->enc = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
373 if (ctx->enc == NULL)
377 set_cdata(cdata, KG_USAGE_SIGN, KEY_USAGE_SEED_CHECKSUM);
378 keyout.data = ctx->cksum;
379 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
381 dprintk("%s: Error %d deriving cksum key\n",
389 crypto_free_skcipher(ctx->enc);
391 crypto_free_skcipher(ctx->seq);
397 * Note that RC4 depends on deriving keys using the sequence
398 * number or the checksum of a token. Therefore, the final keys
399 * cannot be calculated until the token is being constructed!
402 context_derive_keys_rc4(struct krb5_ctx *ctx)
404 struct crypto_shash *hmac;
405 char sigkeyconstant[] = "signaturekey";
406 int slen = strlen(sigkeyconstant) + 1; /* include null terminator */
407 struct shash_desc *desc;
410 dprintk("RPC: %s: entered\n", __func__);
412 * derive cksum (aka Ksign) key
414 hmac = crypto_alloc_shash(ctx->gk5e->cksum_name, 0, 0);
416 dprintk("%s: error %ld allocating hash '%s'\n",
417 __func__, PTR_ERR(hmac), ctx->gk5e->cksum_name);
422 err = crypto_shash_setkey(hmac, ctx->Ksess, ctx->gk5e->keylength);
424 goto out_err_free_hmac;
427 desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(hmac), GFP_NOFS);
429 dprintk("%s: failed to allocate hash descriptor for '%s'\n",
430 __func__, ctx->gk5e->cksum_name);
432 goto out_err_free_hmac;
438 err = crypto_shash_digest(desc, sigkeyconstant, slen, ctx->cksum);
441 goto out_err_free_hmac;
443 * allocate hash, and skciphers for data and seqnum encryption
445 ctx->enc = crypto_alloc_skcipher(ctx->gk5e->encrypt_name, 0,
447 if (IS_ERR(ctx->enc)) {
448 err = PTR_ERR(ctx->enc);
449 goto out_err_free_hmac;
452 ctx->seq = crypto_alloc_skcipher(ctx->gk5e->encrypt_name, 0,
454 if (IS_ERR(ctx->seq)) {
455 crypto_free_skcipher(ctx->enc);
456 err = PTR_ERR(ctx->seq);
457 goto out_err_free_hmac;
460 dprintk("RPC: %s: returning success\n", __func__);
465 crypto_free_shash(hmac);
467 dprintk("RPC: %s: returning %d\n", __func__, err);
472 context_derive_keys_new(struct krb5_ctx *ctx, gfp_t gfp_mask)
474 struct xdr_netobj c, keyin, keyout;
475 u8 cdata[GSS_KRB5_K5CLENGTH];
478 c.len = GSS_KRB5_K5CLENGTH;
481 keyin.data = ctx->Ksess;
482 keyin.len = ctx->gk5e->keylength;
483 keyout.len = ctx->gk5e->keylength;
485 /* initiator seal encryption */
486 set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
487 keyout.data = ctx->initiator_seal;
488 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
490 dprintk("%s: Error %d deriving initiator_seal key\n",
494 ctx->initiator_enc = context_v2_alloc_cipher(ctx,
495 ctx->gk5e->encrypt_name,
496 ctx->initiator_seal);
497 if (ctx->initiator_enc == NULL)
500 /* acceptor seal encryption */
501 set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
502 keyout.data = ctx->acceptor_seal;
503 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
505 dprintk("%s: Error %d deriving acceptor_seal key\n",
507 goto out_free_initiator_enc;
509 ctx->acceptor_enc = context_v2_alloc_cipher(ctx,
510 ctx->gk5e->encrypt_name,
512 if (ctx->acceptor_enc == NULL)
513 goto out_free_initiator_enc;
515 /* initiator sign checksum */
516 set_cdata(cdata, KG_USAGE_INITIATOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
517 keyout.data = ctx->initiator_sign;
518 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
520 dprintk("%s: Error %d deriving initiator_sign key\n",
522 goto out_free_acceptor_enc;
525 /* acceptor sign checksum */
526 set_cdata(cdata, KG_USAGE_ACCEPTOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
527 keyout.data = ctx->acceptor_sign;
528 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
530 dprintk("%s: Error %d deriving acceptor_sign key\n",
532 goto out_free_acceptor_enc;
535 /* initiator seal integrity */
536 set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
537 keyout.data = ctx->initiator_integ;
538 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
540 dprintk("%s: Error %d deriving initiator_integ key\n",
542 goto out_free_acceptor_enc;
545 /* acceptor seal integrity */
546 set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
547 keyout.data = ctx->acceptor_integ;
548 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
550 dprintk("%s: Error %d deriving acceptor_integ key\n",
552 goto out_free_acceptor_enc;
555 switch (ctx->enctype) {
556 case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
557 case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
558 ctx->initiator_enc_aux =
559 context_v2_alloc_cipher(ctx, "cbc(aes)",
560 ctx->initiator_seal);
561 if (ctx->initiator_enc_aux == NULL)
562 goto out_free_acceptor_enc;
563 ctx->acceptor_enc_aux =
564 context_v2_alloc_cipher(ctx, "cbc(aes)",
566 if (ctx->acceptor_enc_aux == NULL) {
567 crypto_free_skcipher(ctx->initiator_enc_aux);
568 goto out_free_acceptor_enc;
574 out_free_acceptor_enc:
575 crypto_free_skcipher(ctx->acceptor_enc);
576 out_free_initiator_enc:
577 crypto_free_skcipher(ctx->initiator_enc);
583 gss_import_v2_context(const void *p, const void *end, struct krb5_ctx *ctx,
588 p = simple_get_bytes(p, end, &ctx->flags, sizeof(ctx->flags));
591 ctx->initiate = ctx->flags & KRB5_CTX_FLAG_INITIATOR;
593 p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
596 p = simple_get_bytes(p, end, &ctx->seq_send64, sizeof(ctx->seq_send64));
599 /* set seq_send for use by "older" enctypes */
600 ctx->seq_send = ctx->seq_send64;
601 if (ctx->seq_send64 != ctx->seq_send) {
602 dprintk("%s: seq_send64 %lx, seq_send %x overflow?\n", __func__,
603 (unsigned long)ctx->seq_send64, ctx->seq_send);
604 p = ERR_PTR(-EINVAL);
607 p = simple_get_bytes(p, end, &ctx->enctype, sizeof(ctx->enctype));
610 /* Map ENCTYPE_DES3_CBC_SHA1 to ENCTYPE_DES3_CBC_RAW */
611 if (ctx->enctype == ENCTYPE_DES3_CBC_SHA1)
612 ctx->enctype = ENCTYPE_DES3_CBC_RAW;
613 ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
614 if (ctx->gk5e == NULL) {
615 dprintk("gss_kerberos_mech: unsupported krb5 enctype %u\n",
617 p = ERR_PTR(-EINVAL);
620 keylen = ctx->gk5e->keylength;
622 p = simple_get_bytes(p, end, ctx->Ksess, keylen);
627 p = ERR_PTR(-EINVAL);
631 ctx->mech_used.data = kmemdup(gss_kerberos_mech.gm_oid.data,
632 gss_kerberos_mech.gm_oid.len, gfp_mask);
633 if (unlikely(ctx->mech_used.data == NULL)) {
634 p = ERR_PTR(-ENOMEM);
637 ctx->mech_used.len = gss_kerberos_mech.gm_oid.len;
639 switch (ctx->enctype) {
640 case ENCTYPE_DES3_CBC_RAW:
641 return context_derive_keys_des3(ctx, gfp_mask);
642 case ENCTYPE_ARCFOUR_HMAC:
643 return context_derive_keys_rc4(ctx);
644 case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
645 case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
646 return context_derive_keys_new(ctx, gfp_mask);
656 gss_import_sec_context_kerberos(const void *p, size_t len,
657 struct gss_ctx *ctx_id,
661 const void *end = (const void *)((const char *)p + len);
662 struct krb5_ctx *ctx;
665 ctx = kzalloc(sizeof(*ctx), gfp_mask);
670 ret = gss_import_v1_context(p, end, ctx);
672 ret = gss_import_v2_context(p, end, ctx, gfp_mask);
675 ctx_id->internal_ctx_id = ctx;
677 *endtime = ctx->endtime;
681 dprintk("RPC: %s: returning %d\n", __func__, ret);
686 gss_delete_sec_context_kerberos(void *internal_ctx) {
687 struct krb5_ctx *kctx = internal_ctx;
689 crypto_free_skcipher(kctx->seq);
690 crypto_free_skcipher(kctx->enc);
691 crypto_free_skcipher(kctx->acceptor_enc);
692 crypto_free_skcipher(kctx->initiator_enc);
693 crypto_free_skcipher(kctx->acceptor_enc_aux);
694 crypto_free_skcipher(kctx->initiator_enc_aux);
695 kfree(kctx->mech_used.data);
699 static const struct gss_api_ops gss_kerberos_ops = {
700 .gss_import_sec_context = gss_import_sec_context_kerberos,
701 .gss_get_mic = gss_get_mic_kerberos,
702 .gss_verify_mic = gss_verify_mic_kerberos,
703 .gss_wrap = gss_wrap_kerberos,
704 .gss_unwrap = gss_unwrap_kerberos,
705 .gss_delete_sec_context = gss_delete_sec_context_kerberos,
708 static struct pf_desc gss_kerberos_pfs[] = {
710 .pseudoflavor = RPC_AUTH_GSS_KRB5,
711 .qop = GSS_C_QOP_DEFAULT,
712 .service = RPC_GSS_SVC_NONE,
716 .pseudoflavor = RPC_AUTH_GSS_KRB5I,
717 .qop = GSS_C_QOP_DEFAULT,
718 .service = RPC_GSS_SVC_INTEGRITY,
723 .pseudoflavor = RPC_AUTH_GSS_KRB5P,
724 .qop = GSS_C_QOP_DEFAULT,
725 .service = RPC_GSS_SVC_PRIVACY,
731 MODULE_ALIAS("rpc-auth-gss-krb5");
732 MODULE_ALIAS("rpc-auth-gss-krb5i");
733 MODULE_ALIAS("rpc-auth-gss-krb5p");
734 MODULE_ALIAS("rpc-auth-gss-390003");
735 MODULE_ALIAS("rpc-auth-gss-390004");
736 MODULE_ALIAS("rpc-auth-gss-390005");
737 MODULE_ALIAS("rpc-auth-gss-1.2.840.113554.1.2.2");
739 static struct gss_api_mech gss_kerberos_mech = {
741 .gm_owner = THIS_MODULE,
742 .gm_oid = { 9, "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02" },
743 .gm_ops = &gss_kerberos_ops,
744 .gm_pf_num = ARRAY_SIZE(gss_kerberos_pfs),
745 .gm_pfs = gss_kerberos_pfs,
746 .gm_upcall_enctypes = KRB5_SUPPORTED_ENCTYPES,
749 static int __init init_kerberos_module(void)
753 status = gss_mech_register(&gss_kerberos_mech);
755 printk("Failed to register kerberos gss mechanism!\n");
759 static void __exit cleanup_kerberos_module(void)
761 gss_mech_unregister(&gss_kerberos_mech);
764 MODULE_LICENSE("GPL");
765 module_init(init_kerberos_module);
766 module_exit(cleanup_kerberos_module);