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v6.8
  1// SPDX-License-Identifier: BSD-3-Clause
  2/*
  3 *  linux/net/sunrpc/gss_krb5_mech.c
  4 *
  5 *  Copyright (c) 2001-2008 The Regents of the University of Michigan.
  6 *  All rights reserved.
  7 *
  8 *  Andy Adamson <andros@umich.edu>
  9 *  J. Bruce Fields <bfields@umich.edu>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 10 */
 11
 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>
 
 23
 24#include "auth_gss_internal.h"
 25#include "gss_krb5_internal.h"
 26
 27#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 28# define RPCDBG_FACILITY	RPCDBG_AUTH
 29#endif
 30
 31static struct gss_api_mech gss_kerberos_mech;
 32
 33static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
 34#if defined(CONFIG_RPCSEC_GSS_KRB5_ENCTYPES_AES_SHA1)
 35	/*
 36	 * AES-128 with SHA-1 (RFC 3962)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 37	 */
 38	{
 39	  .etype = ENCTYPE_AES128_CTS_HMAC_SHA1_96,
 40	  .ctype = CKSUMTYPE_HMAC_SHA1_96_AES128,
 41	  .name = "aes128-cts",
 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,
 48
 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,
 53
 54	  .signalg = -1,
 55	  .sealalg = -1,
 56	  .keybytes = 16,
 57	  .keylength = BITS2OCTETS(128),
 58	  .Kc_length = BITS2OCTETS(128),
 59	  .Ke_length = BITS2OCTETS(128),
 60	  .Ki_length = BITS2OCTETS(128),
 61	  .cksumlength = BITS2OCTETS(96),
 62	  .keyed_cksum = 1,
 63	},
 64	/*
 65	 * AES-256 with SHA-1 (RFC 3962)
 66	 */
 67	{
 68	  .etype = ENCTYPE_AES256_CTS_HMAC_SHA1_96,
 69	  .ctype = CKSUMTYPE_HMAC_SHA1_96_AES256,
 70	  .name = "aes256-cts",
 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,
 77
 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,
 82
 83	  .signalg = -1,
 84	  .sealalg = -1,
 85	  .keybytes = 32,
 86	  .keylength = BITS2OCTETS(256),
 87	  .Kc_length = BITS2OCTETS(256),
 88	  .Ke_length = BITS2OCTETS(256),
 89	  .Ki_length = BITS2OCTETS(256),
 90	  .cksumlength = BITS2OCTETS(96),
 91	  .keyed_cksum = 1,
 92	},
 93#endif
 94
 95#if defined(CONFIG_RPCSEC_GSS_KRB5_ENCTYPES_CAMELLIA)
 96	/*
 97	 * Camellia-128 with CMAC (RFC 6803)
 98	 */
 99	{
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),
107		.keyed_cksum	= 1,
108		.keylength	= BITS2OCTETS(128),
109		.Kc_length	= BITS2OCTETS(128),
110		.Ke_length	= BITS2OCTETS(128),
111		.Ki_length	= BITS2OCTETS(128),
112
113		.derive_key	= krb5_kdf_feedback_cmac,
114		.encrypt	= gss_krb5_aes_encrypt,
115		.decrypt	= gss_krb5_aes_decrypt,
116
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,
121	},
122	/*
123	 * Camellia-256 with CMAC (RFC 6803)
124	 */
125	{
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),
133		.keyed_cksum	= 1,
134		.keylength	= BITS2OCTETS(256),
135		.Kc_length	= BITS2OCTETS(256),
136		.Ke_length	= BITS2OCTETS(256),
137		.Ki_length	= BITS2OCTETS(256),
138
139		.derive_key	= krb5_kdf_feedback_cmac,
140		.encrypt	= gss_krb5_aes_encrypt,
141		.decrypt	= gss_krb5_aes_decrypt,
142
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,
147	},
148#endif
149
150#if defined(CONFIG_RPCSEC_GSS_KRB5_ENCTYPES_AES_SHA2)
151	/*
152	 * AES-128 with SHA-256 (RFC 8009)
153	 */
154	{
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),
162		.keyed_cksum	= 1,
163		.keylength	= BITS2OCTETS(128),
164		.Kc_length	= BITS2OCTETS(128),
165		.Ke_length	= BITS2OCTETS(128),
166		.Ki_length	= BITS2OCTETS(128),
167
168		.derive_key	= krb5_kdf_hmac_sha2,
169		.encrypt	= krb5_etm_encrypt,
170		.decrypt	= krb5_etm_decrypt,
171
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,
176	},
177	/*
178	 * AES-256 with SHA-384 (RFC 8009)
179	 */
180	{
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),
188		.keyed_cksum	= 1,
189		.keylength	= BITS2OCTETS(256),
190		.Kc_length	= BITS2OCTETS(192),
191		.Ke_length	= BITS2OCTETS(256),
192		.Ki_length	= BITS2OCTETS(192),
193
194		.derive_key	= krb5_kdf_hmac_sha2,
195		.encrypt	= krb5_etm_encrypt,
196		.decrypt	= krb5_etm_decrypt,
197
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,
202	},
203#endif
204};
205
206/*
207 * The list of advertised enctypes is specified in order of most
208 * preferred to least.
209 */
210static char gss_krb5_enctype_priority_list[64];
211
212static void gss_krb5_prepare_enctype_priority_list(void)
 
213{
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,
218#endif
219#if defined(CONFIG_RPCSEC_GSS_KRB5_ENCTYPES_CAMELLIA)
220		ENCTYPE_CAMELLIA256_CTS_CMAC,
221		ENCTYPE_CAMELLIA128_CTS_CMAC,
222#endif
223#if defined(CONFIG_RPCSEC_GSS_KRB5_ENCTYPES_AES_SHA1)
224		ENCTYPE_AES256_CTS_HMAC_SHA1_96,
225		ENCTYPE_AES128_CTS_HMAC_SHA1_96,
226#endif
227	};
228	size_t total, i;
229	char buf[16];
230	char *sep;
231	int n;
232
233	sep = "";
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]);
237		if (n < 0)
238			break;
239		if (total + n >= sizeof(gss_krb5_enctype_priority_list))
240			break;
241		strcat(gss_krb5_enctype_priority_list, buf);
242		sep = ",";
243		total += n;
244	}
245}
246
247/**
248 * gss_krb5_lookup_enctype - Retrieve profile information for a given enctype
249 * @etype: ENCTYPE value
250 *
251 * Returns a pointer to a gss_krb5_enctype structure, or NULL if no
252 * matching etype is found.
253 */
254VISIBLE_IF_KUNIT
255const struct gss_krb5_enctype *gss_krb5_lookup_enctype(u32 etype)
256{
257	size_t i;
258
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];
262	return NULL;
263}
264EXPORT_SYMBOL_IF_KUNIT(gss_krb5_lookup_enctype);
265
266static struct crypto_sync_skcipher *
267gss_krb5_alloc_cipher_v2(const char *cname, const struct xdr_netobj *key)
268{
269	struct crypto_sync_skcipher *tfm;
 
 
 
 
 
270
271	tfm = crypto_alloc_sync_skcipher(cname, 0, 0);
272	if (IS_ERR(tfm))
273		return NULL;
274	if (crypto_sync_skcipher_setkey(tfm, key->data, key->len)) {
275		crypto_free_sync_skcipher(tfm);
276		return NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
277	}
278	return tfm;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
279}
280
281static struct crypto_ahash *
282gss_krb5_alloc_hash_v2(struct krb5_ctx *kctx, const struct xdr_netobj *key)
283{
284	struct crypto_ahash *tfm;
285
286	tfm = crypto_alloc_ahash(kctx->gk5e->cksum_name, 0, CRYPTO_ALG_ASYNC);
287	if (IS_ERR(tfm))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
288		return NULL;
289	if (crypto_ahash_setkey(tfm, key->data, key->len)) {
290		crypto_free_ahash(tfm);
 
 
 
291		return NULL;
292	}
293	return tfm;
 
 
 
 
 
 
 
 
 
 
294}
295
296static int
297gss_krb5_import_ctx_v2(struct krb5_ctx *ctx, gfp_t gfp_mask)
298{
299	struct xdr_netobj keyin = {
300		.len	= ctx->gk5e->keylength,
301		.data	= ctx->Ksess,
302	};
303	struct xdr_netobj keyout;
304	int ret = -EINVAL;
 
 
 
 
 
 
 
 
 
 
305
306	keyout.data = kmalloc(GSS_KRB5_MAX_KEYLEN, gfp_mask);
307	if (!keyout.data)
308		return -ENOMEM;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
309
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))
314		goto out;
315	ctx->initiator_enc = gss_krb5_alloc_cipher_v2(ctx->gk5e->encrypt_name,
316						      &keyout);
317	if (ctx->initiator_enc == NULL)
318		goto out;
319	if (ctx->gk5e->aux_cipher) {
320		ctx->initiator_enc_aux =
321			gss_krb5_alloc_cipher_v2(ctx->gk5e->aux_cipher,
322						 &keyout);
323		if (ctx->initiator_enc_aux == NULL)
324			goto out_free;
325	}
 
 
 
 
 
326
327	/* acceptor seal encryption */
328	if (krb5_derive_key(ctx, &keyin, &keyout, KG_USAGE_ACCEPTOR_SEAL,
329			    KEY_USAGE_SEED_ENCRYPTION, gfp_mask))
330		goto out_free;
331	ctx->acceptor_enc = gss_krb5_alloc_cipher_v2(ctx->gk5e->encrypt_name,
332						     &keyout);
333	if (ctx->acceptor_enc == NULL)
334		goto out_free;
335	if (ctx->gk5e->aux_cipher) {
336		ctx->acceptor_enc_aux =
337			gss_krb5_alloc_cipher_v2(ctx->gk5e->aux_cipher,
338						 &keyout);
339		if (ctx->acceptor_enc_aux == NULL)
340			goto out_free;
341	}
 
 
 
 
 
342
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))
347		goto out_free;
348	ctx->initiator_sign = gss_krb5_alloc_hash_v2(ctx, &keyout);
349	if (ctx->initiator_sign == NULL)
350		goto out_free;
 
351
352	/* acceptor sign checksum */
353	if (krb5_derive_key(ctx, &keyin, &keyout, KG_USAGE_ACCEPTOR_SIGN,
354			    KEY_USAGE_SEED_CHECKSUM, gfp_mask))
355		goto out_free;
356	ctx->acceptor_sign = gss_krb5_alloc_hash_v2(ctx, &keyout);
357	if (ctx->acceptor_sign == NULL)
358		goto out_free;
 
 
359
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))
364		goto out_free;
365	ctx->initiator_integ = gss_krb5_alloc_hash_v2(ctx, &keyout);
366	if (ctx->initiator_integ == NULL)
367		goto out_free;
 
368
369	/* acceptor seal integrity */
370	if (krb5_derive_key(ctx, &keyin, &keyout, KG_USAGE_ACCEPTOR_SEAL,
371			    KEY_USAGE_SEED_INTEGRITY, gfp_mask))
372		goto out_free;
373	ctx->acceptor_integ = gss_krb5_alloc_hash_v2(ctx, &keyout);
374	if (ctx->acceptor_integ == NULL)
375		goto out_free;
376
377	ret = 0;
378out:
379	kfree_sensitive(keyout.data);
380	return ret;
381
382out_free:
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);
391	goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
392}
393
394static int
395gss_import_v2_context(const void *p, const void *end, struct krb5_ctx *ctx,
396		gfp_t gfp_mask)
397{
398	u64 seq_send64;
399	int keylen;
400	u32 time32;
401
402	p = simple_get_bytes(p, end, &ctx->flags, sizeof(ctx->flags));
403	if (IS_ERR(p))
404		goto out_err;
405	ctx->initiate = ctx->flags & KRB5_CTX_FLAG_INITIATOR;
406
407	p = simple_get_bytes(p, end, &time32, sizeof(time32));
408	if (IS_ERR(p))
409		goto out_err;
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));
413	if (IS_ERR(p))
414		goto out_err;
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);
422		goto out_err;
423	}
424	p = simple_get_bytes(p, end, &ctx->enctype, sizeof(ctx->enctype));
425	if (IS_ERR(p))
426		goto out_err;
427	ctx->gk5e = gss_krb5_lookup_enctype(ctx->enctype);
 
 
 
428	if (ctx->gk5e == NULL) {
429		dprintk("gss_kerberos_mech: unsupported krb5 enctype %u\n",
430			ctx->enctype);
431		p = ERR_PTR(-EINVAL);
432		goto out_err;
433	}
434	keylen = ctx->gk5e->keylength;
435
436	p = simple_get_bytes(p, end, ctx->Ksess, keylen);
437	if (IS_ERR(p))
438		goto out_err;
439
440	if (p != end) {
441		p = ERR_PTR(-EINVAL);
442		goto out_err;
443	}
444
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);
449		goto out_err;
450	}
451	ctx->mech_used.len = gss_kerberos_mech.gm_oid.len;
452
453	return gss_krb5_import_ctx_v2(ctx, gfp_mask);
 
 
 
 
 
 
 
 
 
 
454
455out_err:
456	return PTR_ERR(p);
457}
458
459static int
460gss_krb5_import_sec_context(const void *p, size_t len, struct gss_ctx *ctx_id,
461			    time64_t *endtime, gfp_t gfp_mask)
 
462{
463	const void *end = (const void *)((const char *)p + len);
464	struct  krb5_ctx *ctx;
465	int ret;
466
467	ctx = kzalloc(sizeof(*ctx), gfp_mask);
468	if (ctx == NULL)
469		return -ENOMEM;
470
471	ret = gss_import_v2_context(p, end, ctx, gfp_mask);
472	memzero_explicit(&ctx->Ksess, sizeof(ctx->Ksess));
473	if (ret) {
 
 
 
 
 
474		kfree(ctx);
475		return ret;
476	}
477
478	ctx_id->internal_ctx_id = ctx;
479	if (endtime)
480		*endtime = ctx->endtime;
481	return 0;
482}
483
484static void
485gss_krb5_delete_sec_context(void *internal_ctx)
486{
487	struct krb5_ctx *kctx = internal_ctx;
488
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);
500	kfree(kctx);
501}
502
503/**
504 * gss_krb5_get_mic - get_mic for the Kerberos GSS mechanism
505 * @gctx: GSS context
506 * @text: plaintext to checksum
507 * @token: buffer into which to write the computed checksum
508 *
509 * Return values:
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
513 */
514static u32 gss_krb5_get_mic(struct gss_ctx *gctx, struct xdr_buf *text,
515			    struct xdr_netobj *token)
516{
517	struct krb5_ctx *kctx = gctx->internal_ctx_id;
518
519	return kctx->gk5e->get_mic(kctx, text, token);
520}
521
522/**
523 * gss_krb5_verify_mic - verify_mic for the Kerberos GSS mechanism
524 * @gctx: GSS context
525 * @message_buffer: plaintext to check
526 * @read_token: received checksum to check
527 *
528 * Return values:
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
534 */
535static u32 gss_krb5_verify_mic(struct gss_ctx *gctx,
536			       struct xdr_buf *message_buffer,
537			       struct xdr_netobj *read_token)
538{
539	struct krb5_ctx *kctx = gctx->internal_ctx_id;
540
541	return kctx->gk5e->verify_mic(kctx, message_buffer, read_token);
542}
543
544/**
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
550 *
551 * Return values:
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
555 */
556static u32 gss_krb5_wrap(struct gss_ctx *gctx, int offset,
557			 struct xdr_buf *buf, struct page **pages)
558{
559	struct krb5_ctx	*kctx = gctx->internal_ctx_id;
560
561	return kctx->gk5e->wrap(kctx, offset, buf, pages);
562}
563
564/**
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
570 *
571 * Return values:
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
577 */
578static u32 gss_krb5_unwrap(struct gss_ctx *gctx, int offset,
579			   int len, struct xdr_buf *buf)
580{
581	struct krb5_ctx	*kctx = gctx->internal_ctx_id;
582
583	return kctx->gk5e->unwrap(kctx, offset, len, buf,
584				  &gctx->slack, &gctx->align);
585}
586
587static 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,
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 = gss_krb5_enctype_priority_list,
635};
636
637static int __init init_kerberos_module(void)
638{
639	int status;
640
641	gss_krb5_prepare_enctype_priority_list();
642	status = gss_mech_register(&gss_kerberos_mech);
643	if (status)
644		printk("Failed to register kerberos gss mechanism!\n");
645	return status;
646}
647
648static void __exit cleanup_kerberos_module(void)
649{
650	gss_mech_unregister(&gss_kerberos_mech);
651}
652
653MODULE_DESCRIPTION("Sun RPC Kerberos 5 module");
654MODULE_LICENSE("GPL");
655module_init(init_kerberos_module);
656module_exit(cleanup_kerberos_module);
v3.1
 
  1/*
  2 *  linux/net/sunrpc/gss_krb5_mech.c
  3 *
  4 *  Copyright (c) 2001-2008 The Regents of the University of Michigan.
  5 *  All rights reserved.
  6 *
  7 *  Andy Adamson <andros@umich.edu>
  8 *  J. Bruce Fields <bfields@umich.edu>
  9 *
 10 *  Redistribution and use in source and binary forms, with or without
 11 *  modification, are permitted provided that the following conditions
 12 *  are met:
 13 *
 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.
 22 *
 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.
 34 *
 35 */
 36
 
 
 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>
 46#include <linux/sunrpc/gss_krb5_enctypes.h>
 47
 48#ifdef RPC_DEBUG
 
 
 
 49# define RPCDBG_FACILITY	RPCDBG_AUTH
 50#endif
 51
 52static struct gss_api_mech gss_kerberos_mech;	/* forward declaration */
 53
 54static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
 
 55	/*
 56	 * DES (All DES enctypes are mapped to the same gss functionality)
 57	 */
 58	{
 59	  .etype = ENCTYPE_DES_CBC_RAW,
 60	  .ctype = CKSUMTYPE_RSA_MD5,
 61	  .name = "des-cbc-crc",
 62	  .encrypt_name = "cbc(des)",
 63	  .cksum_name = "md5",
 64	  .encrypt = krb5_encrypt,
 65	  .decrypt = krb5_decrypt,
 66	  .mk_key = NULL,
 67	  .signalg = SGN_ALG_DES_MAC_MD5,
 68	  .sealalg = SEAL_ALG_DES,
 69	  .keybytes = 7,
 70	  .keylength = 8,
 71	  .blocksize = 8,
 72	  .conflen = 8,
 73	  .cksumlength = 8,
 74	  .keyed_cksum = 0,
 75	},
 76	/*
 77	 * RC4-HMAC
 78	 */
 79	{
 80	  .etype = ENCTYPE_ARCFOUR_HMAC,
 81	  .ctype = CKSUMTYPE_HMAC_MD5_ARCFOUR,
 82	  .name = "rc4-hmac",
 83	  .encrypt_name = "ecb(arc4)",
 84	  .cksum_name = "hmac(md5)",
 85	  .encrypt = krb5_encrypt,
 86	  .decrypt = krb5_decrypt,
 87	  .mk_key = NULL,
 88	  .signalg = SGN_ALG_HMAC_MD5,
 89	  .sealalg = SEAL_ALG_MICROSOFT_RC4,
 90	  .keybytes = 16,
 91	  .keylength = 16,
 92	  .blocksize = 1,
 93	  .conflen = 8,
 94	  .cksumlength = 8,
 95	  .keyed_cksum = 1,
 96	},
 97	/*
 98	 * 3DES
 99	 */
100	{
101	  .etype = ENCTYPE_DES3_CBC_RAW,
102	  .ctype = CKSUMTYPE_HMAC_SHA1_DES3,
103	  .name = "des3-hmac-sha1",
104	  .encrypt_name = "cbc(des3_ede)",
105	  .cksum_name = "hmac(sha1)",
106	  .encrypt = krb5_encrypt,
107	  .decrypt = krb5_decrypt,
108	  .mk_key = gss_krb5_des3_make_key,
109	  .signalg = SGN_ALG_HMAC_SHA1_DES3_KD,
110	  .sealalg = SEAL_ALG_DES3KD,
111	  .keybytes = 21,
112	  .keylength = 24,
113	  .blocksize = 8,
114	  .conflen = 8,
115	  .cksumlength = 20,
116	  .keyed_cksum = 1,
117	},
118	/*
119	 * AES128
120	 */
121	{
122	  .etype = ENCTYPE_AES128_CTS_HMAC_SHA1_96,
123	  .ctype = CKSUMTYPE_HMAC_SHA1_96_AES128,
124	  .name = "aes128-cts",
125	  .encrypt_name = "cts(cbc(aes))",
 
126	  .cksum_name = "hmac(sha1)",
127	  .encrypt = krb5_encrypt,
128	  .decrypt = krb5_decrypt,
129	  .mk_key = gss_krb5_aes_make_key,
130	  .encrypt_v2 = gss_krb5_aes_encrypt,
131	  .decrypt_v2 = gss_krb5_aes_decrypt,
 
 
 
 
132	  .signalg = -1,
133	  .sealalg = -1,
134	  .keybytes = 16,
135	  .keylength = 16,
136	  .blocksize = 16,
137	  .conflen = 16,
138	  .cksumlength = 12,
 
139	  .keyed_cksum = 1,
140	},
141	/*
142	 * AES256
143	 */
144	{
145	  .etype = ENCTYPE_AES256_CTS_HMAC_SHA1_96,
146	  .ctype = CKSUMTYPE_HMAC_SHA1_96_AES256,
147	  .name = "aes256-cts",
148	  .encrypt_name = "cts(cbc(aes))",
 
149	  .cksum_name = "hmac(sha1)",
150	  .encrypt = krb5_encrypt,
151	  .decrypt = krb5_decrypt,
152	  .mk_key = gss_krb5_aes_make_key,
153	  .encrypt_v2 = gss_krb5_aes_encrypt,
154	  .decrypt_v2 = gss_krb5_aes_decrypt,
 
 
 
 
155	  .signalg = -1,
156	  .sealalg = -1,
157	  .keybytes = 32,
158	  .keylength = 32,
159	  .blocksize = 16,
160	  .conflen = 16,
161	  .cksumlength = 12,
 
162	  .keyed_cksum = 1,
163	},
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
164};
165
166static const int num_supported_enctypes =
167	ARRAY_SIZE(supported_gss_krb5_enctypes);
 
 
 
168
169static int
170supported_gss_krb5_enctype(int etype)
171{
172	int i;
173	for (i = 0; i < num_supported_enctypes; i++)
174		if (supported_gss_krb5_enctypes[i].etype == etype)
175			return 1;
176	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
177}
178
179static const struct gss_krb5_enctype *
180get_gss_krb5_enctype(int etype)
 
 
 
 
 
 
 
181{
182	int i;
183	for (i = 0; i < num_supported_enctypes; i++)
 
184		if (supported_gss_krb5_enctypes[i].etype == etype)
185			return &supported_gss_krb5_enctypes[i];
186	return NULL;
187}
 
188
189static const void *
190simple_get_bytes(const void *p, const void *end, void *res, int len)
191{
192	const void *q = (const void *)((const char *)p + len);
193	if (unlikely(q > end || q < p))
194		return ERR_PTR(-EFAULT);
195	memcpy(res, p, len);
196	return q;
197}
198
199static const void *
200simple_get_netobj(const void *p, const void *end, struct xdr_netobj *res)
201{
202	const void *q;
203	unsigned int len;
204
205	p = simple_get_bytes(p, end, &len, sizeof(len));
206	if (IS_ERR(p))
207		return p;
208	q = (const void *)((const char *)p + len);
209	if (unlikely(q > end || q < p))
210		return ERR_PTR(-EFAULT);
211	res->data = kmemdup(p, len, GFP_NOFS);
212	if (unlikely(res->data == NULL))
213		return ERR_PTR(-ENOMEM);
214	res->len = len;
215	return q;
216}
217
218static inline const void *
219get_key(const void *p, const void *end,
220	struct krb5_ctx *ctx, struct crypto_blkcipher **res)
221{
222	struct xdr_netobj	key;
223	int			alg;
224
225	p = simple_get_bytes(p, end, &alg, sizeof(alg));
226	if (IS_ERR(p))
227		goto out_err;
228
229	switch (alg) {
230	case ENCTYPE_DES_CBC_CRC:
231	case ENCTYPE_DES_CBC_MD4:
232	case ENCTYPE_DES_CBC_MD5:
233		/* Map all these key types to ENCTYPE_DES_CBC_RAW */
234		alg = ENCTYPE_DES_CBC_RAW;
235		break;
236	}
237
238	if (!supported_gss_krb5_enctype(alg)) {
239		printk(KERN_WARNING "gss_kerberos_mech: unsupported "
240			"encryption key algorithm %d\n", alg);
241		p = ERR_PTR(-EINVAL);
242		goto out_err;
243	}
244	p = simple_get_netobj(p, end, &key);
245	if (IS_ERR(p))
246		goto out_err;
247
248	*res = crypto_alloc_blkcipher(ctx->gk5e->encrypt_name, 0,
249							CRYPTO_ALG_ASYNC);
250	if (IS_ERR(*res)) {
251		printk(KERN_WARNING "gss_kerberos_mech: unable to initialize "
252			"crypto algorithm %s\n", ctx->gk5e->encrypt_name);
253		*res = NULL;
254		goto out_err_free_key;
255	}
256	if (crypto_blkcipher_setkey(*res, key.data, key.len)) {
257		printk(KERN_WARNING "gss_kerberos_mech: error setting key for "
258			"crypto algorithm %s\n", ctx->gk5e->encrypt_name);
259		goto out_err_free_tfm;
260	}
261
262	kfree(key.data);
263	return p;
264
265out_err_free_tfm:
266	crypto_free_blkcipher(*res);
267out_err_free_key:
268	kfree(key.data);
269	p = ERR_PTR(-EINVAL);
270out_err:
271	return p;
272}
273
274static int
275gss_import_v1_context(const void *p, const void *end, struct krb5_ctx *ctx)
276{
277	int tmp;
278
279	p = simple_get_bytes(p, end, &ctx->initiate, sizeof(ctx->initiate));
280	if (IS_ERR(p))
281		goto out_err;
282
283	/* Old format supports only DES!  Any other enctype uses new format */
284	ctx->enctype = ENCTYPE_DES_CBC_RAW;
285
286	ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
287	if (ctx->gk5e == NULL) {
288		p = ERR_PTR(-EINVAL);
289		goto out_err;
290	}
291
292	/* The downcall format was designed before we completely understood
293	 * the uses of the context fields; so it includes some stuff we
294	 * just give some minimal sanity-checking, and some we ignore
295	 * completely (like the next twenty bytes): */
296	if (unlikely(p + 20 > end || p + 20 < p)) {
297		p = ERR_PTR(-EFAULT);
298		goto out_err;
299	}
300	p += 20;
301	p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
302	if (IS_ERR(p))
303		goto out_err;
304	if (tmp != SGN_ALG_DES_MAC_MD5) {
305		p = ERR_PTR(-ENOSYS);
306		goto out_err;
307	}
308	p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
309	if (IS_ERR(p))
310		goto out_err;
311	if (tmp != SEAL_ALG_DES) {
312		p = ERR_PTR(-ENOSYS);
313		goto out_err;
314	}
315	p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
316	if (IS_ERR(p))
317		goto out_err;
318	p = simple_get_bytes(p, end, &ctx->seq_send, sizeof(ctx->seq_send));
319	if (IS_ERR(p))
320		goto out_err;
321	p = simple_get_netobj(p, end, &ctx->mech_used);
322	if (IS_ERR(p))
323		goto out_err;
324	p = get_key(p, end, ctx, &ctx->enc);
325	if (IS_ERR(p))
326		goto out_err_free_mech;
327	p = get_key(p, end, ctx, &ctx->seq);
328	if (IS_ERR(p))
329		goto out_err_free_key1;
330	if (p != end) {
331		p = ERR_PTR(-EFAULT);
332		goto out_err_free_key2;
333	}
334
335	return 0;
336
337out_err_free_key2:
338	crypto_free_blkcipher(ctx->seq);
339out_err_free_key1:
340	crypto_free_blkcipher(ctx->enc);
341out_err_free_mech:
342	kfree(ctx->mech_used.data);
343out_err:
344	return PTR_ERR(p);
345}
346
347struct crypto_blkcipher *
348context_v2_alloc_cipher(struct krb5_ctx *ctx, const char *cname, u8 *key)
349{
350	struct crypto_blkcipher *cp;
351
352	cp = crypto_alloc_blkcipher(cname, 0, CRYPTO_ALG_ASYNC);
353	if (IS_ERR(cp)) {
354		dprintk("gss_kerberos_mech: unable to initialize "
355			"crypto algorithm %s\n", cname);
356		return NULL;
357	}
358	if (crypto_blkcipher_setkey(cp, key, ctx->gk5e->keylength)) {
359		dprintk("gss_kerberos_mech: error setting key for "
360			"crypto algorithm %s\n", cname);
361		crypto_free_blkcipher(cp);
362		return NULL;
363	}
364	return cp;
365}
366
367static inline void
368set_cdata(u8 cdata[GSS_KRB5_K5CLENGTH], u32 usage, u8 seed)
369{
370	cdata[0] = (usage>>24)&0xff;
371	cdata[1] = (usage>>16)&0xff;
372	cdata[2] = (usage>>8)&0xff;
373	cdata[3] = usage&0xff;
374	cdata[4] = seed;
375}
376
377static int
378context_derive_keys_des3(struct krb5_ctx *ctx, gfp_t gfp_mask)
379{
380	struct xdr_netobj c, keyin, keyout;
381	u8 cdata[GSS_KRB5_K5CLENGTH];
382	u32 err;
383
384	c.len = GSS_KRB5_K5CLENGTH;
385	c.data = cdata;
386
387	keyin.data = ctx->Ksess;
388	keyin.len = ctx->gk5e->keylength;
389	keyout.len = ctx->gk5e->keylength;
390
391	/* seq uses the raw key */
392	ctx->seq = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
393					   ctx->Ksess);
394	if (ctx->seq == NULL)
395		goto out_err;
396
397	ctx->enc = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
398					   ctx->Ksess);
399	if (ctx->enc == NULL)
400		goto out_free_seq;
401
402	/* derive cksum */
403	set_cdata(cdata, KG_USAGE_SIGN, KEY_USAGE_SEED_CHECKSUM);
404	keyout.data = ctx->cksum;
405	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
406	if (err) {
407		dprintk("%s: Error %d deriving cksum key\n",
408			__func__, err);
409		goto out_free_enc;
410	}
411
412	return 0;
413
414out_free_enc:
415	crypto_free_blkcipher(ctx->enc);
416out_free_seq:
417	crypto_free_blkcipher(ctx->seq);
418out_err:
419	return -EINVAL;
420}
421
422/*
423 * Note that RC4 depends on deriving keys using the sequence
424 * number or the checksum of a token.  Therefore, the final keys
425 * cannot be calculated until the token is being constructed!
426 */
427static int
428context_derive_keys_rc4(struct krb5_ctx *ctx)
429{
430	struct crypto_hash *hmac;
431	char sigkeyconstant[] = "signaturekey";
432	int slen = strlen(sigkeyconstant) + 1;	/* include null terminator */
433	struct hash_desc desc;
434	struct scatterlist sg[1];
435	int err;
436
437	dprintk("RPC:       %s: entered\n", __func__);
438	/*
439	 * derive cksum (aka Ksign) key
440	 */
441	hmac = crypto_alloc_hash(ctx->gk5e->cksum_name, 0, CRYPTO_ALG_ASYNC);
442	if (IS_ERR(hmac)) {
443		dprintk("%s: error %ld allocating hash '%s'\n",
444			__func__, PTR_ERR(hmac), ctx->gk5e->cksum_name);
445		err = PTR_ERR(hmac);
446		goto out_err;
447	}
448
449	err = crypto_hash_setkey(hmac, ctx->Ksess, ctx->gk5e->keylength);
450	if (err)
451		goto out_err_free_hmac;
452
453	sg_init_table(sg, 1);
454	sg_set_buf(sg, sigkeyconstant, slen);
455
456	desc.tfm = hmac;
457	desc.flags = 0;
458
459	err = crypto_hash_init(&desc);
460	if (err)
461		goto out_err_free_hmac;
462
463	err = crypto_hash_digest(&desc, sg, slen, ctx->cksum);
464	if (err)
465		goto out_err_free_hmac;
466	/*
467	 * allocate hash, and blkciphers for data and seqnum encryption
468	 */
469	ctx->enc = crypto_alloc_blkcipher(ctx->gk5e->encrypt_name, 0,
470					  CRYPTO_ALG_ASYNC);
471	if (IS_ERR(ctx->enc)) {
472		err = PTR_ERR(ctx->enc);
473		goto out_err_free_hmac;
474	}
475
476	ctx->seq = crypto_alloc_blkcipher(ctx->gk5e->encrypt_name, 0,
477					  CRYPTO_ALG_ASYNC);
478	if (IS_ERR(ctx->seq)) {
479		crypto_free_blkcipher(ctx->enc);
480		err = PTR_ERR(ctx->seq);
481		goto out_err_free_hmac;
482	}
483
484	dprintk("RPC:       %s: returning success\n", __func__);
485
486	err = 0;
487
488out_err_free_hmac:
489	crypto_free_hash(hmac);
490out_err:
491	dprintk("RPC:       %s: returning %d\n", __func__, err);
492	return err;
493}
494
495static int
496context_derive_keys_new(struct krb5_ctx *ctx, gfp_t gfp_mask)
497{
498	struct xdr_netobj c, keyin, keyout;
499	u8 cdata[GSS_KRB5_K5CLENGTH];
500	u32 err;
501
502	c.len = GSS_KRB5_K5CLENGTH;
503	c.data = cdata;
504
505	keyin.data = ctx->Ksess;
506	keyin.len = ctx->gk5e->keylength;
507	keyout.len = ctx->gk5e->keylength;
508
509	/* initiator seal encryption */
510	set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
511	keyout.data = ctx->initiator_seal;
512	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
513	if (err) {
514		dprintk("%s: Error %d deriving initiator_seal key\n",
515			__func__, err);
516		goto out_err;
 
 
 
 
 
 
 
517	}
518	ctx->initiator_enc = context_v2_alloc_cipher(ctx,
519						     ctx->gk5e->encrypt_name,
520						     ctx->initiator_seal);
521	if (ctx->initiator_enc == NULL)
522		goto out_err;
523
524	/* acceptor seal encryption */
525	set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
526	keyout.data = ctx->acceptor_seal;
527	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
528	if (err) {
529		dprintk("%s: Error %d deriving acceptor_seal key\n",
530			__func__, err);
531		goto out_free_initiator_enc;
 
 
 
 
 
 
532	}
533	ctx->acceptor_enc = context_v2_alloc_cipher(ctx,
534						    ctx->gk5e->encrypt_name,
535						    ctx->acceptor_seal);
536	if (ctx->acceptor_enc == NULL)
537		goto out_free_initiator_enc;
538
539	/* initiator sign checksum */
540	set_cdata(cdata, KG_USAGE_INITIATOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
541	keyout.data = ctx->initiator_sign;
542	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
543	if (err) {
544		dprintk("%s: Error %d deriving initiator_sign key\n",
545			__func__, err);
546		goto out_free_acceptor_enc;
547	}
548
549	/* acceptor sign checksum */
550	set_cdata(cdata, KG_USAGE_ACCEPTOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
551	keyout.data = ctx->acceptor_sign;
552	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
553	if (err) {
554		dprintk("%s: Error %d deriving acceptor_sign key\n",
555			__func__, err);
556		goto out_free_acceptor_enc;
557	}
558
559	/* initiator seal integrity */
560	set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
561	keyout.data = ctx->initiator_integ;
562	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
563	if (err) {
564		dprintk("%s: Error %d deriving initiator_integ key\n",
565			__func__, err);
566		goto out_free_acceptor_enc;
567	}
568
569	/* acceptor seal integrity */
570	set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
571	keyout.data = ctx->acceptor_integ;
572	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
573	if (err) {
574		dprintk("%s: Error %d deriving acceptor_integ key\n",
575			__func__, err);
576		goto out_free_acceptor_enc;
577	}
 
 
 
578
579	switch (ctx->enctype) {
580	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
581	case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
582		ctx->initiator_enc_aux =
583			context_v2_alloc_cipher(ctx, "cbc(aes)",
584						ctx->initiator_seal);
585		if (ctx->initiator_enc_aux == NULL)
586			goto out_free_acceptor_enc;
587		ctx->acceptor_enc_aux =
588			context_v2_alloc_cipher(ctx, "cbc(aes)",
589						ctx->acceptor_seal);
590		if (ctx->acceptor_enc_aux == NULL) {
591			crypto_free_blkcipher(ctx->initiator_enc_aux);
592			goto out_free_acceptor_enc;
593		}
594	}
595
596	return 0;
597
598out_free_acceptor_enc:
599	crypto_free_blkcipher(ctx->acceptor_enc);
600out_free_initiator_enc:
601	crypto_free_blkcipher(ctx->initiator_enc);
602out_err:
603	return -EINVAL;
604}
605
606static int
607gss_import_v2_context(const void *p, const void *end, struct krb5_ctx *ctx,
608		gfp_t gfp_mask)
609{
 
610	int keylen;
 
611
612	p = simple_get_bytes(p, end, &ctx->flags, sizeof(ctx->flags));
613	if (IS_ERR(p))
614		goto out_err;
615	ctx->initiate = ctx->flags & KRB5_CTX_FLAG_INITIATOR;
616
617	p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
618	if (IS_ERR(p))
619		goto out_err;
620	p = simple_get_bytes(p, end, &ctx->seq_send64, sizeof(ctx->seq_send64));
 
 
621	if (IS_ERR(p))
622		goto out_err;
 
623	/* set seq_send for use by "older" enctypes */
624	ctx->seq_send = ctx->seq_send64;
625	if (ctx->seq_send64 != ctx->seq_send) {
626		dprintk("%s: seq_send64 %lx, seq_send %x overflow?\n", __func__,
627			(long unsigned)ctx->seq_send64, ctx->seq_send);
628		p = ERR_PTR(-EINVAL);
629		goto out_err;
630	}
631	p = simple_get_bytes(p, end, &ctx->enctype, sizeof(ctx->enctype));
632	if (IS_ERR(p))
633		goto out_err;
634	/* Map ENCTYPE_DES3_CBC_SHA1 to ENCTYPE_DES3_CBC_RAW */
635	if (ctx->enctype == ENCTYPE_DES3_CBC_SHA1)
636		ctx->enctype = ENCTYPE_DES3_CBC_RAW;
637	ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
638	if (ctx->gk5e == NULL) {
639		dprintk("gss_kerberos_mech: unsupported krb5 enctype %u\n",
640			ctx->enctype);
641		p = ERR_PTR(-EINVAL);
642		goto out_err;
643	}
644	keylen = ctx->gk5e->keylength;
645
646	p = simple_get_bytes(p, end, ctx->Ksess, keylen);
647	if (IS_ERR(p))
648		goto out_err;
649
650	if (p != end) {
651		p = ERR_PTR(-EINVAL);
652		goto out_err;
653	}
654
655	ctx->mech_used.data = kmemdup(gss_kerberos_mech.gm_oid.data,
656				      gss_kerberos_mech.gm_oid.len, gfp_mask);
657	if (unlikely(ctx->mech_used.data == NULL)) {
658		p = ERR_PTR(-ENOMEM);
659		goto out_err;
660	}
661	ctx->mech_used.len = gss_kerberos_mech.gm_oid.len;
662
663	switch (ctx->enctype) {
664	case ENCTYPE_DES3_CBC_RAW:
665		return context_derive_keys_des3(ctx, gfp_mask);
666	case ENCTYPE_ARCFOUR_HMAC:
667		return context_derive_keys_rc4(ctx);
668	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
669	case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
670		return context_derive_keys_new(ctx, gfp_mask);
671	default:
672		return -EINVAL;
673	}
674
675out_err:
676	return PTR_ERR(p);
677}
678
679static int
680gss_import_sec_context_kerberos(const void *p, size_t len,
681				struct gss_ctx *ctx_id,
682				gfp_t gfp_mask)
683{
684	const void *end = (const void *)((const char *)p + len);
685	struct  krb5_ctx *ctx;
686	int ret;
687
688	ctx = kzalloc(sizeof(*ctx), gfp_mask);
689	if (ctx == NULL)
690		return -ENOMEM;
691
692	if (len == 85)
693		ret = gss_import_v1_context(p, end, ctx);
694	else
695		ret = gss_import_v2_context(p, end, ctx, gfp_mask);
696
697	if (ret == 0)
698		ctx_id->internal_ctx_id = ctx;
699	else
700		kfree(ctx);
 
 
701
702	dprintk("RPC:       %s: returning %d\n", __func__, ret);
703	return ret;
 
 
704}
705
706static void
707gss_delete_sec_context_kerberos(void *internal_ctx) {
 
708	struct krb5_ctx *kctx = internal_ctx;
709
710	crypto_free_blkcipher(kctx->seq);
711	crypto_free_blkcipher(kctx->enc);
712	crypto_free_blkcipher(kctx->acceptor_enc);
713	crypto_free_blkcipher(kctx->initiator_enc);
714	crypto_free_blkcipher(kctx->acceptor_enc_aux);
715	crypto_free_blkcipher(kctx->initiator_enc_aux);
 
 
 
 
716	kfree(kctx->mech_used.data);
717	kfree(kctx);
718}
719
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
720static const struct gss_api_ops gss_kerberos_ops = {
721	.gss_import_sec_context	= gss_import_sec_context_kerberos,
722	.gss_get_mic		= gss_get_mic_kerberos,
723	.gss_verify_mic		= gss_verify_mic_kerberos,
724	.gss_wrap		= gss_wrap_kerberos,
725	.gss_unwrap		= gss_unwrap_kerberos,
726	.gss_delete_sec_context	= gss_delete_sec_context_kerberos,
727};
728
729static struct pf_desc gss_kerberos_pfs[] = {
730	[0] = {
731		.pseudoflavor = RPC_AUTH_GSS_KRB5,
 
732		.service = RPC_GSS_SVC_NONE,
733		.name = "krb5",
734	},
735	[1] = {
736		.pseudoflavor = RPC_AUTH_GSS_KRB5I,
 
737		.service = RPC_GSS_SVC_INTEGRITY,
738		.name = "krb5i",
 
739	},
740	[2] = {
741		.pseudoflavor = RPC_AUTH_GSS_KRB5P,
 
742		.service = RPC_GSS_SVC_PRIVACY,
743		.name = "krb5p",
 
744	},
745};
746
747MODULE_ALIAS("rpc-auth-gss-krb5");
748MODULE_ALIAS("rpc-auth-gss-krb5i");
749MODULE_ALIAS("rpc-auth-gss-krb5p");
750MODULE_ALIAS("rpc-auth-gss-390003");
751MODULE_ALIAS("rpc-auth-gss-390004");
752MODULE_ALIAS("rpc-auth-gss-390005");
 
753
754static struct gss_api_mech gss_kerberos_mech = {
755	.gm_name	= "krb5",
756	.gm_owner	= THIS_MODULE,
757	.gm_oid		= {9, (void *)"\x2a\x86\x48\x86\xf7\x12\x01\x02\x02"},
758	.gm_ops		= &gss_kerberos_ops,
759	.gm_pf_num	= ARRAY_SIZE(gss_kerberos_pfs),
760	.gm_pfs		= gss_kerberos_pfs,
761	.gm_upcall_enctypes = KRB5_SUPPORTED_ENCTYPES,
762};
763
764static int __init init_kerberos_module(void)
765{
766	int status;
767
 
768	status = gss_mech_register(&gss_kerberos_mech);
769	if (status)
770		printk("Failed to register kerberos gss mechanism!\n");
771	return status;
772}
773
774static void __exit cleanup_kerberos_module(void)
775{
776	gss_mech_unregister(&gss_kerberos_mech);
777}
778
 
779MODULE_LICENSE("GPL");
780module_init(init_kerberos_module);
781module_exit(cleanup_kerberos_module);