1 // SPDX-License-Identifier: BSD-3-Clause
3 * linux/net/sunrpc/gss_krb5_mech.c
5 * Copyright (c) 2001-2008 The Regents of the University of Michigan.
8 * Andy Adamson <andros@umich.edu>
9 * J. Bruce Fields <bfields@umich.edu>
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 <kunit/visibility.h>
24 #include "auth_gss_internal.h"
25 #include "gss_krb5_internal.h"
27 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
28 # define RPCDBG_FACILITY RPCDBG_AUTH
31 static struct gss_api_mech gss_kerberos_mech;
33 static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
34 #if defined(CONFIG_RPCSEC_GSS_KRB5_ENCTYPES_AES_SHA1)
36 * AES-128 with SHA-1 (RFC 3962)
39 .etype = ENCTYPE_AES128_CTS_HMAC_SHA1_96,
40 .ctype = CKSUMTYPE_HMAC_SHA1_96_AES128,
42 .encrypt_name = "cts(cbc(aes))",
43 .aux_cipher = "cbc(aes)",
44 .cksum_name = "hmac(sha1)",
45 .derive_key = krb5_derive_key_v2,
46 .encrypt = gss_krb5_aes_encrypt,
47 .decrypt = gss_krb5_aes_decrypt,
49 .get_mic = gss_krb5_get_mic_v2,
50 .verify_mic = gss_krb5_verify_mic_v2,
51 .wrap = gss_krb5_wrap_v2,
52 .unwrap = gss_krb5_unwrap_v2,
57 .keylength = BITS2OCTETS(128),
58 .Kc_length = BITS2OCTETS(128),
59 .Ke_length = BITS2OCTETS(128),
60 .Ki_length = BITS2OCTETS(128),
61 .cksumlength = BITS2OCTETS(96),
65 * AES-256 with SHA-1 (RFC 3962)
68 .etype = ENCTYPE_AES256_CTS_HMAC_SHA1_96,
69 .ctype = CKSUMTYPE_HMAC_SHA1_96_AES256,
71 .encrypt_name = "cts(cbc(aes))",
72 .aux_cipher = "cbc(aes)",
73 .cksum_name = "hmac(sha1)",
74 .derive_key = krb5_derive_key_v2,
75 .encrypt = gss_krb5_aes_encrypt,
76 .decrypt = gss_krb5_aes_decrypt,
78 .get_mic = gss_krb5_get_mic_v2,
79 .verify_mic = gss_krb5_verify_mic_v2,
80 .wrap = gss_krb5_wrap_v2,
81 .unwrap = gss_krb5_unwrap_v2,
86 .keylength = BITS2OCTETS(256),
87 .Kc_length = BITS2OCTETS(256),
88 .Ke_length = BITS2OCTETS(256),
89 .Ki_length = BITS2OCTETS(256),
90 .cksumlength = BITS2OCTETS(96),
95 #if defined(CONFIG_RPCSEC_GSS_KRB5_ENCTYPES_CAMELLIA)
97 * Camellia-128 with CMAC (RFC 6803)
100 .etype = ENCTYPE_CAMELLIA128_CTS_CMAC,
101 .ctype = CKSUMTYPE_CMAC_CAMELLIA128,
102 .name = "camellia128-cts-cmac",
103 .encrypt_name = "cts(cbc(camellia))",
104 .aux_cipher = "cbc(camellia)",
105 .cksum_name = "cmac(camellia)",
106 .cksumlength = BITS2OCTETS(128),
108 .keylength = BITS2OCTETS(128),
109 .Kc_length = BITS2OCTETS(128),
110 .Ke_length = BITS2OCTETS(128),
111 .Ki_length = BITS2OCTETS(128),
113 .derive_key = krb5_kdf_feedback_cmac,
114 .encrypt = gss_krb5_aes_encrypt,
115 .decrypt = gss_krb5_aes_decrypt,
117 .get_mic = gss_krb5_get_mic_v2,
118 .verify_mic = gss_krb5_verify_mic_v2,
119 .wrap = gss_krb5_wrap_v2,
120 .unwrap = gss_krb5_unwrap_v2,
123 * Camellia-256 with CMAC (RFC 6803)
126 .etype = ENCTYPE_CAMELLIA256_CTS_CMAC,
127 .ctype = CKSUMTYPE_CMAC_CAMELLIA256,
128 .name = "camellia256-cts-cmac",
129 .encrypt_name = "cts(cbc(camellia))",
130 .aux_cipher = "cbc(camellia)",
131 .cksum_name = "cmac(camellia)",
132 .cksumlength = BITS2OCTETS(128),
134 .keylength = BITS2OCTETS(256),
135 .Kc_length = BITS2OCTETS(256),
136 .Ke_length = BITS2OCTETS(256),
137 .Ki_length = BITS2OCTETS(256),
139 .derive_key = krb5_kdf_feedback_cmac,
140 .encrypt = gss_krb5_aes_encrypt,
141 .decrypt = gss_krb5_aes_decrypt,
143 .get_mic = gss_krb5_get_mic_v2,
144 .verify_mic = gss_krb5_verify_mic_v2,
145 .wrap = gss_krb5_wrap_v2,
146 .unwrap = gss_krb5_unwrap_v2,
150 #if defined(CONFIG_RPCSEC_GSS_KRB5_ENCTYPES_AES_SHA2)
152 * AES-128 with SHA-256 (RFC 8009)
155 .etype = ENCTYPE_AES128_CTS_HMAC_SHA256_128,
156 .ctype = CKSUMTYPE_HMAC_SHA256_128_AES128,
157 .name = "aes128-cts-hmac-sha256-128",
158 .encrypt_name = "cts(cbc(aes))",
159 .aux_cipher = "cbc(aes)",
160 .cksum_name = "hmac(sha256)",
161 .cksumlength = BITS2OCTETS(128),
163 .keylength = BITS2OCTETS(128),
164 .Kc_length = BITS2OCTETS(128),
165 .Ke_length = BITS2OCTETS(128),
166 .Ki_length = BITS2OCTETS(128),
168 .derive_key = krb5_kdf_hmac_sha2,
169 .encrypt = krb5_etm_encrypt,
170 .decrypt = krb5_etm_decrypt,
172 .get_mic = gss_krb5_get_mic_v2,
173 .verify_mic = gss_krb5_verify_mic_v2,
174 .wrap = gss_krb5_wrap_v2,
175 .unwrap = gss_krb5_unwrap_v2,
178 * AES-256 with SHA-384 (RFC 8009)
181 .etype = ENCTYPE_AES256_CTS_HMAC_SHA384_192,
182 .ctype = CKSUMTYPE_HMAC_SHA384_192_AES256,
183 .name = "aes256-cts-hmac-sha384-192",
184 .encrypt_name = "cts(cbc(aes))",
185 .aux_cipher = "cbc(aes)",
186 .cksum_name = "hmac(sha384)",
187 .cksumlength = BITS2OCTETS(192),
189 .keylength = BITS2OCTETS(256),
190 .Kc_length = BITS2OCTETS(192),
191 .Ke_length = BITS2OCTETS(256),
192 .Ki_length = BITS2OCTETS(192),
194 .derive_key = krb5_kdf_hmac_sha2,
195 .encrypt = krb5_etm_encrypt,
196 .decrypt = krb5_etm_decrypt,
198 .get_mic = gss_krb5_get_mic_v2,
199 .verify_mic = gss_krb5_verify_mic_v2,
200 .wrap = gss_krb5_wrap_v2,
201 .unwrap = gss_krb5_unwrap_v2,
207 * The list of advertised enctypes is specified in order of most
208 * preferred to least.
210 static char gss_krb5_enctype_priority_list[64];
212 static void gss_krb5_prepare_enctype_priority_list(void)
214 static const u32 gss_krb5_enctypes[] = {
215 #if defined(CONFIG_RPCSEC_GSS_KRB5_ENCTYPES_AES_SHA2)
216 ENCTYPE_AES256_CTS_HMAC_SHA384_192,
217 ENCTYPE_AES128_CTS_HMAC_SHA256_128,
219 #if defined(CONFIG_RPCSEC_GSS_KRB5_ENCTYPES_CAMELLIA)
220 ENCTYPE_CAMELLIA256_CTS_CMAC,
221 ENCTYPE_CAMELLIA128_CTS_CMAC,
223 #if defined(CONFIG_RPCSEC_GSS_KRB5_ENCTYPES_AES_SHA1)
224 ENCTYPE_AES256_CTS_HMAC_SHA1_96,
225 ENCTYPE_AES128_CTS_HMAC_SHA1_96,
234 gss_krb5_enctype_priority_list[0] = '\0';
235 for (total = 0, i = 0; i < ARRAY_SIZE(gss_krb5_enctypes); i++) {
236 n = sprintf(buf, "%s%u", sep, gss_krb5_enctypes[i]);
239 if (total + n >= sizeof(gss_krb5_enctype_priority_list))
241 strcat(gss_krb5_enctype_priority_list, buf);
248 * gss_krb5_lookup_enctype - Retrieve profile information for a given enctype
249 * @etype: ENCTYPE value
251 * Returns a pointer to a gss_krb5_enctype structure, or NULL if no
252 * matching etype is found.
255 const struct gss_krb5_enctype *gss_krb5_lookup_enctype(u32 etype)
259 for (i = 0; i < ARRAY_SIZE(supported_gss_krb5_enctypes); i++)
260 if (supported_gss_krb5_enctypes[i].etype == etype)
261 return &supported_gss_krb5_enctypes[i];
264 EXPORT_SYMBOL_IF_KUNIT(gss_krb5_lookup_enctype);
266 static struct crypto_sync_skcipher *
267 gss_krb5_alloc_cipher_v2(const char *cname, const struct xdr_netobj *key)
269 struct crypto_sync_skcipher *tfm;
271 tfm = crypto_alloc_sync_skcipher(cname, 0, 0);
274 if (crypto_sync_skcipher_setkey(tfm, key->data, key->len)) {
275 crypto_free_sync_skcipher(tfm);
281 static struct crypto_ahash *
282 gss_krb5_alloc_hash_v2(struct krb5_ctx *kctx, const struct xdr_netobj *key)
284 struct crypto_ahash *tfm;
286 tfm = crypto_alloc_ahash(kctx->gk5e->cksum_name, 0, CRYPTO_ALG_ASYNC);
289 if (crypto_ahash_setkey(tfm, key->data, key->len)) {
290 crypto_free_ahash(tfm);
297 gss_krb5_import_ctx_v2(struct krb5_ctx *ctx, gfp_t gfp_mask)
299 struct xdr_netobj keyin = {
300 .len = ctx->gk5e->keylength,
303 struct xdr_netobj keyout;
306 keyout.data = kmalloc(GSS_KRB5_MAX_KEYLEN, gfp_mask);
310 /* initiator seal encryption */
311 keyout.len = ctx->gk5e->Ke_length;
312 if (krb5_derive_key(ctx, &keyin, &keyout, KG_USAGE_INITIATOR_SEAL,
313 KEY_USAGE_SEED_ENCRYPTION, gfp_mask))
315 ctx->initiator_enc = gss_krb5_alloc_cipher_v2(ctx->gk5e->encrypt_name,
317 if (ctx->initiator_enc == NULL)
319 if (ctx->gk5e->aux_cipher) {
320 ctx->initiator_enc_aux =
321 gss_krb5_alloc_cipher_v2(ctx->gk5e->aux_cipher,
323 if (ctx->initiator_enc_aux == NULL)
327 /* acceptor seal encryption */
328 if (krb5_derive_key(ctx, &keyin, &keyout, KG_USAGE_ACCEPTOR_SEAL,
329 KEY_USAGE_SEED_ENCRYPTION, gfp_mask))
331 ctx->acceptor_enc = gss_krb5_alloc_cipher_v2(ctx->gk5e->encrypt_name,
333 if (ctx->acceptor_enc == NULL)
335 if (ctx->gk5e->aux_cipher) {
336 ctx->acceptor_enc_aux =
337 gss_krb5_alloc_cipher_v2(ctx->gk5e->aux_cipher,
339 if (ctx->acceptor_enc_aux == NULL)
343 /* initiator sign checksum */
344 keyout.len = ctx->gk5e->Kc_length;
345 if (krb5_derive_key(ctx, &keyin, &keyout, KG_USAGE_INITIATOR_SIGN,
346 KEY_USAGE_SEED_CHECKSUM, gfp_mask))
348 ctx->initiator_sign = gss_krb5_alloc_hash_v2(ctx, &keyout);
349 if (ctx->initiator_sign == NULL)
352 /* acceptor sign checksum */
353 if (krb5_derive_key(ctx, &keyin, &keyout, KG_USAGE_ACCEPTOR_SIGN,
354 KEY_USAGE_SEED_CHECKSUM, gfp_mask))
356 ctx->acceptor_sign = gss_krb5_alloc_hash_v2(ctx, &keyout);
357 if (ctx->acceptor_sign == NULL)
360 /* initiator seal integrity */
361 keyout.len = ctx->gk5e->Ki_length;
362 if (krb5_derive_key(ctx, &keyin, &keyout, KG_USAGE_INITIATOR_SEAL,
363 KEY_USAGE_SEED_INTEGRITY, gfp_mask))
365 ctx->initiator_integ = gss_krb5_alloc_hash_v2(ctx, &keyout);
366 if (ctx->initiator_integ == NULL)
369 /* acceptor seal integrity */
370 if (krb5_derive_key(ctx, &keyin, &keyout, KG_USAGE_ACCEPTOR_SEAL,
371 KEY_USAGE_SEED_INTEGRITY, gfp_mask))
373 ctx->acceptor_integ = gss_krb5_alloc_hash_v2(ctx, &keyout);
374 if (ctx->acceptor_integ == NULL)
379 kfree_sensitive(keyout.data);
383 crypto_free_ahash(ctx->acceptor_integ);
384 crypto_free_ahash(ctx->initiator_integ);
385 crypto_free_ahash(ctx->acceptor_sign);
386 crypto_free_ahash(ctx->initiator_sign);
387 crypto_free_sync_skcipher(ctx->acceptor_enc_aux);
388 crypto_free_sync_skcipher(ctx->acceptor_enc);
389 crypto_free_sync_skcipher(ctx->initiator_enc_aux);
390 crypto_free_sync_skcipher(ctx->initiator_enc);
395 gss_import_v2_context(const void *p, const void *end, struct krb5_ctx *ctx,
402 p = simple_get_bytes(p, end, &ctx->flags, sizeof(ctx->flags));
405 ctx->initiate = ctx->flags & KRB5_CTX_FLAG_INITIATOR;
407 p = simple_get_bytes(p, end, &time32, sizeof(time32));
410 /* unsigned 32-bit time overflows in year 2106 */
411 ctx->endtime = (time64_t)time32;
412 p = simple_get_bytes(p, end, &seq_send64, sizeof(seq_send64));
415 atomic64_set(&ctx->seq_send64, seq_send64);
416 /* set seq_send for use by "older" enctypes */
417 atomic_set(&ctx->seq_send, seq_send64);
418 if (seq_send64 != atomic_read(&ctx->seq_send)) {
419 dprintk("%s: seq_send64 %llx, seq_send %x overflow?\n", __func__,
420 seq_send64, atomic_read(&ctx->seq_send));
421 p = ERR_PTR(-EINVAL);
424 p = simple_get_bytes(p, end, &ctx->enctype, sizeof(ctx->enctype));
427 ctx->gk5e = gss_krb5_lookup_enctype(ctx->enctype);
428 if (ctx->gk5e == NULL) {
429 dprintk("gss_kerberos_mech: unsupported krb5 enctype %u\n",
431 p = ERR_PTR(-EINVAL);
434 keylen = ctx->gk5e->keylength;
436 p = simple_get_bytes(p, end, ctx->Ksess, keylen);
441 p = ERR_PTR(-EINVAL);
445 ctx->mech_used.data = kmemdup(gss_kerberos_mech.gm_oid.data,
446 gss_kerberos_mech.gm_oid.len, gfp_mask);
447 if (unlikely(ctx->mech_used.data == NULL)) {
448 p = ERR_PTR(-ENOMEM);
451 ctx->mech_used.len = gss_kerberos_mech.gm_oid.len;
453 return gss_krb5_import_ctx_v2(ctx, gfp_mask);
460 gss_krb5_import_sec_context(const void *p, size_t len, struct gss_ctx *ctx_id,
461 time64_t *endtime, gfp_t gfp_mask)
463 const void *end = (const void *)((const char *)p + len);
464 struct krb5_ctx *ctx;
467 ctx = kzalloc(sizeof(*ctx), gfp_mask);
471 ret = gss_import_v2_context(p, end, ctx, gfp_mask);
472 memzero_explicit(&ctx->Ksess, sizeof(ctx->Ksess));
478 ctx_id->internal_ctx_id = ctx;
480 *endtime = ctx->endtime;
485 gss_krb5_delete_sec_context(void *internal_ctx)
487 struct krb5_ctx *kctx = internal_ctx;
489 crypto_free_sync_skcipher(kctx->seq);
490 crypto_free_sync_skcipher(kctx->enc);
491 crypto_free_sync_skcipher(kctx->acceptor_enc);
492 crypto_free_sync_skcipher(kctx->initiator_enc);
493 crypto_free_sync_skcipher(kctx->acceptor_enc_aux);
494 crypto_free_sync_skcipher(kctx->initiator_enc_aux);
495 crypto_free_ahash(kctx->acceptor_sign);
496 crypto_free_ahash(kctx->initiator_sign);
497 crypto_free_ahash(kctx->acceptor_integ);
498 crypto_free_ahash(kctx->initiator_integ);
499 kfree(kctx->mech_used.data);
504 * gss_krb5_get_mic - get_mic for the Kerberos GSS mechanism
506 * @text: plaintext to checksum
507 * @token: buffer into which to write the computed checksum
510 * %GSS_S_COMPLETE - success, and @token is filled in
511 * %GSS_S_FAILURE - checksum could not be generated
512 * %GSS_S_CONTEXT_EXPIRED - Kerberos context is no longer valid
514 static u32 gss_krb5_get_mic(struct gss_ctx *gctx, struct xdr_buf *text,
515 struct xdr_netobj *token)
517 struct krb5_ctx *kctx = gctx->internal_ctx_id;
519 return kctx->gk5e->get_mic(kctx, text, token);
523 * gss_krb5_verify_mic - verify_mic for the Kerberos GSS mechanism
525 * @message_buffer: plaintext to check
526 * @read_token: received checksum to check
529 * %GSS_S_COMPLETE - computed and received checksums match
530 * %GSS_S_DEFECTIVE_TOKEN - received checksum is not valid
531 * %GSS_S_BAD_SIG - computed and received checksums do not match
532 * %GSS_S_FAILURE - received checksum could not be checked
533 * %GSS_S_CONTEXT_EXPIRED - Kerberos context is no longer valid
535 static u32 gss_krb5_verify_mic(struct gss_ctx *gctx,
536 struct xdr_buf *message_buffer,
537 struct xdr_netobj *read_token)
539 struct krb5_ctx *kctx = gctx->internal_ctx_id;
541 return kctx->gk5e->verify_mic(kctx, message_buffer, read_token);
545 * gss_krb5_wrap - gss_wrap for the Kerberos GSS mechanism
546 * @gctx: initialized GSS context
547 * @offset: byte offset in @buf to start writing the cipher text
548 * @buf: OUT: send buffer
549 * @pages: plaintext to wrap
552 * %GSS_S_COMPLETE - success, @buf has been updated
553 * %GSS_S_FAILURE - @buf could not be wrapped
554 * %GSS_S_CONTEXT_EXPIRED - Kerberos context is no longer valid
556 static u32 gss_krb5_wrap(struct gss_ctx *gctx, int offset,
557 struct xdr_buf *buf, struct page **pages)
559 struct krb5_ctx *kctx = gctx->internal_ctx_id;
561 return kctx->gk5e->wrap(kctx, offset, buf, pages);
565 * gss_krb5_unwrap - gss_unwrap for the Kerberos GSS mechanism
566 * @gctx: initialized GSS context
567 * @offset: starting byte offset into @buf
568 * @len: size of ciphertext to unwrap
569 * @buf: ciphertext to unwrap
572 * %GSS_S_COMPLETE - success, @buf has been updated
573 * %GSS_S_DEFECTIVE_TOKEN - received blob is not valid
574 * %GSS_S_BAD_SIG - computed and received checksums do not match
575 * %GSS_S_FAILURE - @buf could not be unwrapped
576 * %GSS_S_CONTEXT_EXPIRED - Kerberos context is no longer valid
578 static u32 gss_krb5_unwrap(struct gss_ctx *gctx, int offset,
579 int len, struct xdr_buf *buf)
581 struct krb5_ctx *kctx = gctx->internal_ctx_id;
583 return kctx->gk5e->unwrap(kctx, offset, len, buf,
584 &gctx->slack, &gctx->align);
587 static const struct gss_api_ops gss_kerberos_ops = {
588 .gss_import_sec_context = gss_krb5_import_sec_context,
589 .gss_get_mic = gss_krb5_get_mic,
590 .gss_verify_mic = gss_krb5_verify_mic,
591 .gss_wrap = gss_krb5_wrap,
592 .gss_unwrap = gss_krb5_unwrap,
593 .gss_delete_sec_context = gss_krb5_delete_sec_context,
596 static struct pf_desc gss_kerberos_pfs[] = {
598 .pseudoflavor = RPC_AUTH_GSS_KRB5,
599 .qop = GSS_C_QOP_DEFAULT,
600 .service = RPC_GSS_SVC_NONE,
604 .pseudoflavor = RPC_AUTH_GSS_KRB5I,
605 .qop = GSS_C_QOP_DEFAULT,
606 .service = RPC_GSS_SVC_INTEGRITY,
611 .pseudoflavor = RPC_AUTH_GSS_KRB5P,
612 .qop = GSS_C_QOP_DEFAULT,
613 .service = RPC_GSS_SVC_PRIVACY,
619 MODULE_ALIAS("rpc-auth-gss-krb5");
620 MODULE_ALIAS("rpc-auth-gss-krb5i");
621 MODULE_ALIAS("rpc-auth-gss-krb5p");
622 MODULE_ALIAS("rpc-auth-gss-390003");
623 MODULE_ALIAS("rpc-auth-gss-390004");
624 MODULE_ALIAS("rpc-auth-gss-390005");
625 MODULE_ALIAS("rpc-auth-gss-1.2.840.113554.1.2.2");
627 static struct gss_api_mech gss_kerberos_mech = {
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 = gss_krb5_enctype_priority_list,
637 static int __init init_kerberos_module(void)
641 gss_krb5_prepare_enctype_priority_list();
642 status = gss_mech_register(&gss_kerberos_mech);
644 printk("Failed to register kerberos gss mechanism!\n");
648 static void __exit cleanup_kerberos_module(void)
650 gss_mech_unregister(&gss_kerberos_mech);
653 MODULE_LICENSE("GPL");
654 module_init(init_kerberos_module);
655 module_exit(cleanup_kerberos_module);