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 <linux/err.h>
38 #include <linux/module.h>
39 #include <linux/init.h>
40 #include <linux/types.h>
41 #include <linux/slab.h>
42 #include <linux/sunrpc/auth.h>
43 #include <linux/sunrpc/gss_krb5.h>
44 #include <linux/sunrpc/xdr.h>
45 #include <linux/crypto.h>
48 # define RPCDBG_FACILITY RPCDBG_AUTH
51 static struct gss_api_mech gss_kerberos_mech; /* forward declaration */
53 static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
55 * DES (All DES enctypes are mapped to the same gss functionality)
58 .etype = ENCTYPE_DES_CBC_RAW,
59 .ctype = CKSUMTYPE_RSA_MD5,
60 .name = "des-cbc-crc",
61 .encrypt_name = "cbc(des)",
63 .encrypt = krb5_encrypt,
64 .decrypt = krb5_decrypt,
66 .signalg = SGN_ALG_DES_MAC_MD5,
67 .sealalg = SEAL_ALG_DES,
78 .etype = ENCTYPE_DES3_CBC_RAW,
79 .ctype = CKSUMTYPE_HMAC_SHA1_DES3,
80 .name = "des3-hmac-sha1",
81 .encrypt_name = "cbc(des3_ede)",
82 .cksum_name = "hmac(sha1)",
83 .encrypt = krb5_encrypt,
84 .decrypt = krb5_decrypt,
85 .mk_key = gss_krb5_des3_make_key,
86 .signalg = SGN_ALG_HMAC_SHA1_DES3_KD,
87 .sealalg = SEAL_ALG_DES3KD,
98 .etype = ENCTYPE_AES128_CTS_HMAC_SHA1_96,
99 .ctype = CKSUMTYPE_HMAC_SHA1_96_AES128,
100 .name = "aes128-cts",
101 .encrypt_name = "cts(cbc(aes))",
102 .cksum_name = "hmac(sha1)",
103 .encrypt = krb5_encrypt,
104 .decrypt = krb5_decrypt,
105 .mk_key = gss_krb5_aes_make_key,
106 .encrypt_v2 = gss_krb5_aes_encrypt,
107 .decrypt_v2 = gss_krb5_aes_decrypt,
120 .etype = ENCTYPE_AES256_CTS_HMAC_SHA1_96,
121 .ctype = CKSUMTYPE_HMAC_SHA1_96_AES256,
122 .name = "aes256-cts",
123 .encrypt_name = "cts(cbc(aes))",
124 .cksum_name = "hmac(sha1)",
125 .encrypt = krb5_encrypt,
126 .decrypt = krb5_decrypt,
127 .mk_key = gss_krb5_aes_make_key,
128 .encrypt_v2 = gss_krb5_aes_encrypt,
129 .decrypt_v2 = gss_krb5_aes_decrypt,
140 static const int num_supported_enctypes =
141 ARRAY_SIZE(supported_gss_krb5_enctypes);
144 supported_gss_krb5_enctype(int etype)
147 for (i = 0; i < num_supported_enctypes; i++)
148 if (supported_gss_krb5_enctypes[i].etype == etype)
153 static const struct gss_krb5_enctype *
154 get_gss_krb5_enctype(int etype)
157 for (i = 0; i < num_supported_enctypes; i++)
158 if (supported_gss_krb5_enctypes[i].etype == etype)
159 return &supported_gss_krb5_enctypes[i];
164 simple_get_bytes(const void *p, const void *end, void *res, int len)
166 const void *q = (const void *)((const char *)p + len);
167 if (unlikely(q > end || q < p))
168 return ERR_PTR(-EFAULT);
174 simple_get_netobj(const void *p, const void *end, struct xdr_netobj *res)
179 p = simple_get_bytes(p, end, &len, sizeof(len));
182 q = (const void *)((const char *)p + len);
183 if (unlikely(q > end || q < p))
184 return ERR_PTR(-EFAULT);
185 res->data = kmemdup(p, len, GFP_NOFS);
186 if (unlikely(res->data == NULL))
187 return ERR_PTR(-ENOMEM);
192 static inline const void *
193 get_key(const void *p, const void *end,
194 struct krb5_ctx *ctx, struct crypto_blkcipher **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);
217 p = simple_get_netobj(p, end, &key);
221 *res = crypto_alloc_blkcipher(ctx->gk5e->encrypt_name, 0,
224 printk(KERN_WARNING "gss_kerberos_mech: unable to initialize "
225 "crypto algorithm %s\n", ctx->gk5e->encrypt_name);
227 goto out_err_free_key;
229 if (crypto_blkcipher_setkey(*res, key.data, key.len)) {
230 printk(KERN_WARNING "gss_kerberos_mech: error setting key for "
231 "crypto algorithm %s\n", ctx->gk5e->encrypt_name);
232 goto out_err_free_tfm;
239 crypto_free_blkcipher(*res);
242 p = ERR_PTR(-EINVAL);
248 gss_import_v1_context(const void *p, const void *end, struct krb5_ctx *ctx)
252 p = simple_get_bytes(p, end, &ctx->initiate, sizeof(ctx->initiate));
256 /* Old format supports only DES! Any other enctype uses new format */
257 ctx->enctype = ENCTYPE_DES_CBC_RAW;
259 ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
260 if (ctx->gk5e == NULL)
263 /* The downcall format was designed before we completely understood
264 * the uses of the context fields; so it includes some stuff we
265 * just give some minimal sanity-checking, and some we ignore
266 * completely (like the next twenty bytes): */
267 if (unlikely(p + 20 > end || p + 20 < p))
270 p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
273 if (tmp != SGN_ALG_DES_MAC_MD5) {
274 p = ERR_PTR(-ENOSYS);
277 p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
280 if (tmp != SEAL_ALG_DES) {
281 p = ERR_PTR(-ENOSYS);
284 p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
287 p = simple_get_bytes(p, end, &ctx->seq_send, sizeof(ctx->seq_send));
290 p = simple_get_netobj(p, end, &ctx->mech_used);
293 p = get_key(p, end, ctx, &ctx->enc);
295 goto out_err_free_mech;
296 p = get_key(p, end, ctx, &ctx->seq);
298 goto out_err_free_key1;
300 p = ERR_PTR(-EFAULT);
301 goto out_err_free_key2;
307 crypto_free_blkcipher(ctx->seq);
309 crypto_free_blkcipher(ctx->enc);
311 kfree(ctx->mech_used.data);
316 struct crypto_blkcipher *
317 context_v2_alloc_cipher(struct krb5_ctx *ctx, const char *cname, u8 *key)
319 struct crypto_blkcipher *cp;
321 cp = crypto_alloc_blkcipher(cname, 0, CRYPTO_ALG_ASYNC);
323 dprintk("gss_kerberos_mech: unable to initialize "
324 "crypto algorithm %s\n", cname);
327 if (crypto_blkcipher_setkey(cp, key, ctx->gk5e->keylength)) {
328 dprintk("gss_kerberos_mech: error setting key for "
329 "crypto algorithm %s\n", cname);
330 crypto_free_blkcipher(cp);
337 set_cdata(u8 cdata[GSS_KRB5_K5CLENGTH], u32 usage, u8 seed)
339 cdata[0] = (usage>>24)&0xff;
340 cdata[1] = (usage>>16)&0xff;
341 cdata[2] = (usage>>8)&0xff;
342 cdata[3] = usage&0xff;
347 context_derive_keys_des3(struct krb5_ctx *ctx, u8 *rawkey, u32 keylen)
349 struct xdr_netobj c, keyin, keyout;
350 u8 cdata[GSS_KRB5_K5CLENGTH];
353 c.len = GSS_KRB5_K5CLENGTH;
360 /* seq uses the raw key */
361 ctx->seq = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
363 if (ctx->seq == NULL)
366 ctx->enc = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
368 if (ctx->enc == NULL)
372 set_cdata(cdata, KG_USAGE_SIGN, KEY_USAGE_SEED_CHECKSUM);
373 keyout.data = ctx->cksum;
374 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
376 dprintk("%s: Error %d deriving cksum key\n",
384 crypto_free_blkcipher(ctx->enc);
386 crypto_free_blkcipher(ctx->seq);
392 context_derive_keys_new(struct krb5_ctx *ctx, u8 *rawkey, u32 keylen)
394 struct xdr_netobj c, keyin, keyout;
395 u8 cdata[GSS_KRB5_K5CLENGTH];
398 c.len = GSS_KRB5_K5CLENGTH;
405 /* initiator seal encryption */
406 set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
407 keyout.data = ctx->initiator_seal;
408 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
410 dprintk("%s: Error %d deriving initiator_seal key\n",
414 ctx->initiator_enc = context_v2_alloc_cipher(ctx,
415 ctx->gk5e->encrypt_name,
416 ctx->initiator_seal);
417 if (ctx->initiator_enc == NULL)
420 /* acceptor seal encryption */
421 set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
422 keyout.data = ctx->acceptor_seal;
423 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
425 dprintk("%s: Error %d deriving acceptor_seal key\n",
427 goto out_free_initiator_enc;
429 ctx->acceptor_enc = context_v2_alloc_cipher(ctx,
430 ctx->gk5e->encrypt_name,
432 if (ctx->acceptor_enc == NULL)
433 goto out_free_initiator_enc;
435 /* initiator sign checksum */
436 set_cdata(cdata, KG_USAGE_INITIATOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
437 keyout.data = ctx->initiator_sign;
438 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
440 dprintk("%s: Error %d deriving initiator_sign key\n",
442 goto out_free_acceptor_enc;
445 /* acceptor sign checksum */
446 set_cdata(cdata, KG_USAGE_ACCEPTOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
447 keyout.data = ctx->acceptor_sign;
448 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
450 dprintk("%s: Error %d deriving acceptor_sign key\n",
452 goto out_free_acceptor_enc;
455 /* initiator seal integrity */
456 set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
457 keyout.data = ctx->initiator_integ;
458 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
460 dprintk("%s: Error %d deriving initiator_integ key\n",
462 goto out_free_acceptor_enc;
465 /* acceptor seal integrity */
466 set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
467 keyout.data = ctx->acceptor_integ;
468 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
470 dprintk("%s: Error %d deriving acceptor_integ key\n",
472 goto out_free_acceptor_enc;
475 switch (ctx->enctype) {
476 case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
477 case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
478 ctx->initiator_enc_aux =
479 context_v2_alloc_cipher(ctx, "cbc(aes)",
480 ctx->initiator_seal);
481 if (ctx->initiator_enc_aux == NULL)
482 goto out_free_acceptor_enc;
483 ctx->acceptor_enc_aux =
484 context_v2_alloc_cipher(ctx, "cbc(aes)",
486 if (ctx->acceptor_enc_aux == NULL) {
487 crypto_free_blkcipher(ctx->initiator_enc_aux);
488 goto out_free_acceptor_enc;
494 out_free_acceptor_enc:
495 crypto_free_blkcipher(ctx->acceptor_enc);
496 out_free_initiator_enc:
497 crypto_free_blkcipher(ctx->initiator_enc);
503 gss_import_v2_context(const void *p, const void *end, struct krb5_ctx *ctx)
505 u8 rawkey[GSS_KRB5_MAX_KEYLEN];
508 p = simple_get_bytes(p, end, &ctx->flags, sizeof(ctx->flags));
511 ctx->initiate = ctx->flags & KRB5_CTX_FLAG_INITIATOR;
513 p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
516 p = simple_get_bytes(p, end, &ctx->seq_send64, sizeof(ctx->seq_send64));
519 /* set seq_send for use by "older" enctypes */
520 ctx->seq_send = ctx->seq_send64;
521 if (ctx->seq_send64 != ctx->seq_send) {
522 dprintk("%s: seq_send64 %lx, seq_send %x overflow?\n", __func__,
523 (long unsigned)ctx->seq_send64, ctx->seq_send);
526 p = simple_get_bytes(p, end, &ctx->enctype, sizeof(ctx->enctype));
529 /* Map ENCTYPE_DES3_CBC_SHA1 to ENCTYPE_DES3_CBC_RAW */
530 if (ctx->enctype == ENCTYPE_DES3_CBC_SHA1)
531 ctx->enctype = ENCTYPE_DES3_CBC_RAW;
532 ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
533 if (ctx->gk5e == NULL) {
534 dprintk("gss_kerberos_mech: unsupported krb5 enctype %u\n",
536 p = ERR_PTR(-EINVAL);
539 keylen = ctx->gk5e->keylength;
541 p = simple_get_bytes(p, end, rawkey, keylen);
546 p = ERR_PTR(-EINVAL);
550 ctx->mech_used.data = kmemdup(gss_kerberos_mech.gm_oid.data,
551 gss_kerberos_mech.gm_oid.len, GFP_KERNEL);
552 if (unlikely(ctx->mech_used.data == NULL)) {
553 p = ERR_PTR(-ENOMEM);
556 ctx->mech_used.len = gss_kerberos_mech.gm_oid.len;
558 switch (ctx->enctype) {
559 case ENCTYPE_DES3_CBC_RAW:
560 return context_derive_keys_des3(ctx, rawkey, keylen);
561 case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
562 case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
563 return context_derive_keys_new(ctx, rawkey, keylen);
573 gss_import_sec_context_kerberos(const void *p, size_t len,
574 struct gss_ctx *ctx_id)
576 const void *end = (const void *)((const char *)p + len);
577 struct krb5_ctx *ctx;
580 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
585 ret = gss_import_v1_context(p, end, ctx);
587 ret = gss_import_v2_context(p, end, ctx);
590 ctx_id->internal_ctx_id = ctx;
594 dprintk("RPC: %s: returning %d\n", __func__, ret);
599 gss_delete_sec_context_kerberos(void *internal_ctx) {
600 struct krb5_ctx *kctx = internal_ctx;
602 crypto_free_blkcipher(kctx->seq);
603 crypto_free_blkcipher(kctx->enc);
604 crypto_free_blkcipher(kctx->acceptor_enc);
605 crypto_free_blkcipher(kctx->initiator_enc);
606 crypto_free_blkcipher(kctx->acceptor_enc_aux);
607 crypto_free_blkcipher(kctx->initiator_enc_aux);
608 kfree(kctx->mech_used.data);
612 static const struct gss_api_ops gss_kerberos_ops = {
613 .gss_import_sec_context = gss_import_sec_context_kerberos,
614 .gss_get_mic = gss_get_mic_kerberos,
615 .gss_verify_mic = gss_verify_mic_kerberos,
616 .gss_wrap = gss_wrap_kerberos,
617 .gss_unwrap = gss_unwrap_kerberos,
618 .gss_delete_sec_context = gss_delete_sec_context_kerberos,
621 static struct pf_desc gss_kerberos_pfs[] = {
623 .pseudoflavor = RPC_AUTH_GSS_KRB5,
624 .service = RPC_GSS_SVC_NONE,
628 .pseudoflavor = RPC_AUTH_GSS_KRB5I,
629 .service = RPC_GSS_SVC_INTEGRITY,
633 .pseudoflavor = RPC_AUTH_GSS_KRB5P,
634 .service = RPC_GSS_SVC_PRIVACY,
639 static struct gss_api_mech gss_kerberos_mech = {
641 .gm_owner = THIS_MODULE,
642 .gm_oid = {9, (void *)"\x2a\x86\x48\x86\xf7\x12\x01\x02\x02"},
643 .gm_ops = &gss_kerberos_ops,
644 .gm_pf_num = ARRAY_SIZE(gss_kerberos_pfs),
645 .gm_pfs = gss_kerberos_pfs,
646 .gm_upcall_enctypes = "enctypes=16,3,1,2 ",
649 static int __init init_kerberos_module(void)
653 status = gss_mech_register(&gss_kerberos_mech);
655 printk("Failed to register kerberos gss mechanism!\n");
659 static void __exit cleanup_kerberos_module(void)
661 gss_mech_unregister(&gss_kerberos_mech);
664 MODULE_LICENSE("GPL");
665 module_init(init_kerberos_module);
666 module_exit(cleanup_kerberos_module);