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,
76 static const int num_supported_enctypes =
77 ARRAY_SIZE(supported_gss_krb5_enctypes);
80 supported_gss_krb5_enctype(int etype)
83 for (i = 0; i < num_supported_enctypes; i++)
84 if (supported_gss_krb5_enctypes[i].etype == etype)
89 static const struct gss_krb5_enctype *
90 get_gss_krb5_enctype(int etype)
93 for (i = 0; i < num_supported_enctypes; i++)
94 if (supported_gss_krb5_enctypes[i].etype == etype)
95 return &supported_gss_krb5_enctypes[i];
100 simple_get_bytes(const void *p, const void *end, void *res, int len)
102 const void *q = (const void *)((const char *)p + len);
103 if (unlikely(q > end || q < p))
104 return ERR_PTR(-EFAULT);
110 simple_get_netobj(const void *p, const void *end, struct xdr_netobj *res)
115 p = simple_get_bytes(p, end, &len, sizeof(len));
118 q = (const void *)((const char *)p + len);
119 if (unlikely(q > end || q < p))
120 return ERR_PTR(-EFAULT);
121 res->data = kmemdup(p, len, GFP_NOFS);
122 if (unlikely(res->data == NULL))
123 return ERR_PTR(-ENOMEM);
128 static inline const void *
129 get_key(const void *p, const void *end,
130 struct krb5_ctx *ctx, struct crypto_blkcipher **res)
132 struct xdr_netobj key;
135 p = simple_get_bytes(p, end, &alg, sizeof(alg));
140 case ENCTYPE_DES_CBC_CRC:
141 case ENCTYPE_DES_CBC_MD4:
142 case ENCTYPE_DES_CBC_MD5:
143 /* Map all these key types to ENCTYPE_DES_CBC_RAW */
144 alg = ENCTYPE_DES_CBC_RAW;
148 if (!supported_gss_krb5_enctype(alg)) {
149 printk(KERN_WARNING "gss_kerberos_mech: unsupported "
150 "encryption key algorithm %d\n", alg);
153 p = simple_get_netobj(p, end, &key);
157 *res = crypto_alloc_blkcipher(ctx->gk5e->encrypt_name, 0,
160 printk(KERN_WARNING "gss_kerberos_mech: unable to initialize "
161 "crypto algorithm %s\n", ctx->gk5e->encrypt_name);
163 goto out_err_free_key;
165 if (crypto_blkcipher_setkey(*res, key.data, key.len)) {
166 printk(KERN_WARNING "gss_kerberos_mech: error setting key for "
167 "crypto algorithm %s\n", ctx->gk5e->encrypt_name);
168 goto out_err_free_tfm;
175 crypto_free_blkcipher(*res);
178 p = ERR_PTR(-EINVAL);
184 gss_import_v1_context(const void *p, const void *end, struct krb5_ctx *ctx)
188 p = simple_get_bytes(p, end, &ctx->initiate, sizeof(ctx->initiate));
192 /* Old format supports only DES! Any other enctype uses new format */
193 ctx->enctype = ENCTYPE_DES_CBC_RAW;
195 ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
196 if (ctx->gk5e == NULL)
199 /* The downcall format was designed before we completely understood
200 * the uses of the context fields; so it includes some stuff we
201 * just give some minimal sanity-checking, and some we ignore
202 * completely (like the next twenty bytes): */
203 if (unlikely(p + 20 > end || p + 20 < p))
206 p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
209 if (tmp != SGN_ALG_DES_MAC_MD5) {
210 p = ERR_PTR(-ENOSYS);
213 p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
216 if (tmp != SEAL_ALG_DES) {
217 p = ERR_PTR(-ENOSYS);
220 p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
223 p = simple_get_bytes(p, end, &ctx->seq_send, sizeof(ctx->seq_send));
226 p = simple_get_netobj(p, end, &ctx->mech_used);
229 p = get_key(p, end, ctx, &ctx->enc);
231 goto out_err_free_mech;
232 p = get_key(p, end, ctx, &ctx->seq);
234 goto out_err_free_key1;
236 p = ERR_PTR(-EFAULT);
237 goto out_err_free_key2;
243 crypto_free_blkcipher(ctx->seq);
245 crypto_free_blkcipher(ctx->enc);
247 kfree(ctx->mech_used.data);
252 struct crypto_blkcipher *
253 context_v2_alloc_cipher(struct krb5_ctx *ctx, u8 *key)
255 struct crypto_blkcipher *cp;
257 cp = crypto_alloc_blkcipher(ctx->gk5e->encrypt_name,
258 0, CRYPTO_ALG_ASYNC);
260 dprintk("gss_kerberos_mech: unable to initialize "
261 "crypto algorithm %s\n", ctx->gk5e->encrypt_name);
264 if (crypto_blkcipher_setkey(cp, key, ctx->gk5e->keylength)) {
265 dprintk("gss_kerberos_mech: error setting key for "
266 "crypto algorithm %s\n", ctx->gk5e->encrypt_name);
267 crypto_free_blkcipher(cp);
274 set_cdata(u8 cdata[GSS_KRB5_K5CLENGTH], u32 usage, u8 seed)
276 cdata[0] = (usage>>24)&0xff;
277 cdata[1] = (usage>>16)&0xff;
278 cdata[2] = (usage>>8)&0xff;
279 cdata[3] = usage&0xff;
284 context_derive_keys_des3(struct krb5_ctx *ctx, u8 *rawkey, u32 keylen)
286 struct xdr_netobj c, keyin, keyout;
287 u8 cdata[GSS_KRB5_K5CLENGTH];
290 c.len = GSS_KRB5_K5CLENGTH;
297 /* seq uses the raw key */
298 ctx->seq = context_v2_alloc_cipher(ctx, rawkey);
299 if (ctx->seq == NULL)
302 ctx->enc = context_v2_alloc_cipher(ctx, rawkey);
303 if (ctx->enc == NULL)
307 set_cdata(cdata, KG_USAGE_SIGN, KEY_USAGE_SEED_CHECKSUM);
308 keyout.data = ctx->cksum;
309 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
311 dprintk("%s: Error %d deriving cksum key\n",
319 crypto_free_blkcipher(ctx->enc);
321 crypto_free_blkcipher(ctx->seq);
327 context_derive_keys_new(struct krb5_ctx *ctx, u8 *rawkey, u32 keylen)
329 struct xdr_netobj c, keyin, keyout;
330 u8 cdata[GSS_KRB5_K5CLENGTH];
333 c.len = GSS_KRB5_K5CLENGTH;
340 /* initiator seal encryption */
341 set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
342 keyout.data = ctx->initiator_seal;
343 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
345 dprintk("%s: Error %d deriving initiator_seal key\n",
349 ctx->initiator_enc = context_v2_alloc_cipher(ctx, ctx->initiator_seal);
350 if (ctx->initiator_enc == NULL)
353 /* acceptor seal encryption */
354 set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
355 keyout.data = ctx->acceptor_seal;
356 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
358 dprintk("%s: Error %d deriving acceptor_seal key\n",
360 goto out_free_initiator_enc;
362 ctx->acceptor_enc = context_v2_alloc_cipher(ctx, ctx->acceptor_seal);
363 if (ctx->acceptor_enc == NULL)
364 goto out_free_initiator_enc;
366 /* initiator sign checksum */
367 set_cdata(cdata, KG_USAGE_INITIATOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
368 keyout.data = ctx->initiator_sign;
369 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
371 dprintk("%s: Error %d deriving initiator_sign key\n",
373 goto out_free_acceptor_enc;
376 /* acceptor sign checksum */
377 set_cdata(cdata, KG_USAGE_ACCEPTOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
378 keyout.data = ctx->acceptor_sign;
379 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
381 dprintk("%s: Error %d deriving acceptor_sign key\n",
383 goto out_free_acceptor_enc;
386 /* initiator seal integrity */
387 set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
388 keyout.data = ctx->initiator_integ;
389 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
391 dprintk("%s: Error %d deriving initiator_integ key\n",
393 goto out_free_acceptor_enc;
396 /* acceptor seal integrity */
397 set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
398 keyout.data = ctx->acceptor_integ;
399 err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
401 dprintk("%s: Error %d deriving acceptor_integ key\n",
403 goto out_free_acceptor_enc;
408 out_free_acceptor_enc:
409 crypto_free_blkcipher(ctx->acceptor_enc);
410 out_free_initiator_enc:
411 crypto_free_blkcipher(ctx->initiator_enc);
417 gss_import_v2_context(const void *p, const void *end, struct krb5_ctx *ctx)
419 u8 rawkey[GSS_KRB5_MAX_KEYLEN];
422 p = simple_get_bytes(p, end, &ctx->flags, sizeof(ctx->flags));
425 ctx->initiate = ctx->flags & KRB5_CTX_FLAG_INITIATOR;
427 p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
430 p = simple_get_bytes(p, end, &ctx->seq_send64, sizeof(ctx->seq_send64));
433 /* set seq_send for use by "older" enctypes */
434 ctx->seq_send = ctx->seq_send64;
435 if (ctx->seq_send64 != ctx->seq_send) {
436 dprintk("%s: seq_send64 %lx, seq_send %x overflow?\n", __func__,
437 (long unsigned)ctx->seq_send64, ctx->seq_send);
440 p = simple_get_bytes(p, end, &ctx->enctype, sizeof(ctx->enctype));
443 ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
444 if (ctx->gk5e == NULL) {
445 dprintk("gss_kerberos_mech: unsupported krb5 enctype %u\n",
447 p = ERR_PTR(-EINVAL);
450 keylen = ctx->gk5e->keylength;
452 p = simple_get_bytes(p, end, rawkey, keylen);
457 p = ERR_PTR(-EINVAL);
461 ctx->mech_used.data = kmemdup(gss_kerberos_mech.gm_oid.data,
462 gss_kerberos_mech.gm_oid.len, GFP_KERNEL);
463 if (unlikely(ctx->mech_used.data == NULL)) {
464 p = ERR_PTR(-ENOMEM);
467 ctx->mech_used.len = gss_kerberos_mech.gm_oid.len;
469 switch (ctx->enctype) {
470 case ENCTYPE_DES3_CBC_RAW:
471 return context_derive_keys_des3(ctx, rawkey, keylen);
472 case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
473 case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
474 return context_derive_keys_new(ctx, rawkey, keylen);
484 gss_import_sec_context_kerberos(const void *p, size_t len,
485 struct gss_ctx *ctx_id)
487 const void *end = (const void *)((const char *)p + len);
488 struct krb5_ctx *ctx;
491 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
496 ret = gss_import_v1_context(p, end, ctx);
498 ret = gss_import_v2_context(p, end, ctx);
501 ctx_id->internal_ctx_id = ctx;
505 dprintk("RPC: %s: returning %d\n", __func__, ret);
510 gss_delete_sec_context_kerberos(void *internal_ctx) {
511 struct krb5_ctx *kctx = internal_ctx;
513 crypto_free_blkcipher(kctx->seq);
514 crypto_free_blkcipher(kctx->enc);
515 crypto_free_blkcipher(kctx->acceptor_enc);
516 crypto_free_blkcipher(kctx->initiator_enc);
517 kfree(kctx->mech_used.data);
521 static const struct gss_api_ops gss_kerberos_ops = {
522 .gss_import_sec_context = gss_import_sec_context_kerberos,
523 .gss_get_mic = gss_get_mic_kerberos,
524 .gss_verify_mic = gss_verify_mic_kerberos,
525 .gss_wrap = gss_wrap_kerberos,
526 .gss_unwrap = gss_unwrap_kerberos,
527 .gss_delete_sec_context = gss_delete_sec_context_kerberos,
530 static struct pf_desc gss_kerberos_pfs[] = {
532 .pseudoflavor = RPC_AUTH_GSS_KRB5,
533 .service = RPC_GSS_SVC_NONE,
537 .pseudoflavor = RPC_AUTH_GSS_KRB5I,
538 .service = RPC_GSS_SVC_INTEGRITY,
542 .pseudoflavor = RPC_AUTH_GSS_KRB5P,
543 .service = RPC_GSS_SVC_PRIVACY,
548 static struct gss_api_mech gss_kerberos_mech = {
550 .gm_owner = THIS_MODULE,
551 .gm_oid = {9, (void *)"\x2a\x86\x48\x86\xf7\x12\x01\x02\x02"},
552 .gm_ops = &gss_kerberos_ops,
553 .gm_pf_num = ARRAY_SIZE(gss_kerberos_pfs),
554 .gm_pfs = gss_kerberos_pfs,
557 static int __init init_kerberos_module(void)
561 status = gss_mech_register(&gss_kerberos_mech);
563 printk("Failed to register kerberos gss mechanism!\n");
567 static void __exit cleanup_kerberos_module(void)
569 gss_mech_unregister(&gss_kerberos_mech);
572 MODULE_LICENSE("GPL");
573 module_init(init_kerberos_module);
574 module_exit(cleanup_kerberos_module);