Linux Audio

Check our new training course

Loading...
v6.2
  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 <linux/sunrpc/gss_krb5_enctypes.h>
 23
 24#include "auth_gss_internal.h"
 25
 26#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 27# define RPCDBG_FACILITY	RPCDBG_AUTH
 28#endif
 29
 30static struct gss_api_mech gss_kerberos_mech;	/* forward declaration */
 31
 32static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
 33#ifndef CONFIG_SUNRPC_DISABLE_INSECURE_ENCTYPES
 34	/*
 35	 * DES (All DES enctypes are mapped to the same gss functionality)
 36	 */
 37	{
 38	  .etype = ENCTYPE_DES_CBC_RAW,
 39	  .ctype = CKSUMTYPE_RSA_MD5,
 40	  .name = "des-cbc-crc",
 41	  .encrypt_name = "cbc(des)",
 42	  .cksum_name = "md5",
 43	  .encrypt = krb5_encrypt,
 44	  .decrypt = krb5_decrypt,
 45	  .mk_key = NULL,
 46	  .signalg = SGN_ALG_DES_MAC_MD5,
 47	  .sealalg = SEAL_ALG_DES,
 48	  .keybytes = 7,
 49	  .keylength = 8,
 50	  .blocksize = 8,
 51	  .conflen = 8,
 52	  .cksumlength = 8,
 53	  .keyed_cksum = 0,
 54	},
 55#endif	/* CONFIG_SUNRPC_DISABLE_INSECURE_ENCTYPES */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 56	/*
 57	 * 3DES
 58	 */
 59	{
 60	  .etype = ENCTYPE_DES3_CBC_RAW,
 61	  .ctype = CKSUMTYPE_HMAC_SHA1_DES3,
 62	  .name = "des3-hmac-sha1",
 63	  .encrypt_name = "cbc(des3_ede)",
 64	  .cksum_name = "hmac(sha1)",
 65	  .encrypt = krb5_encrypt,
 66	  .decrypt = krb5_decrypt,
 67	  .mk_key = gss_krb5_des3_make_key,
 68	  .signalg = SGN_ALG_HMAC_SHA1_DES3_KD,
 69	  .sealalg = SEAL_ALG_DES3KD,
 70	  .keybytes = 21,
 71	  .keylength = 24,
 72	  .blocksize = 8,
 73	  .conflen = 8,
 74	  .cksumlength = 20,
 75	  .keyed_cksum = 1,
 76	},
 77	/*
 78	 * AES128
 79	 */
 80	{
 81	  .etype = ENCTYPE_AES128_CTS_HMAC_SHA1_96,
 82	  .ctype = CKSUMTYPE_HMAC_SHA1_96_AES128,
 83	  .name = "aes128-cts",
 84	  .encrypt_name = "cts(cbc(aes))",
 85	  .cksum_name = "hmac(sha1)",
 86	  .encrypt = krb5_encrypt,
 87	  .decrypt = krb5_decrypt,
 88	  .mk_key = gss_krb5_aes_make_key,
 89	  .encrypt_v2 = gss_krb5_aes_encrypt,
 90	  .decrypt_v2 = gss_krb5_aes_decrypt,
 91	  .signalg = -1,
 92	  .sealalg = -1,
 93	  .keybytes = 16,
 94	  .keylength = 16,
 95	  .blocksize = 16,
 96	  .conflen = 16,
 97	  .cksumlength = 12,
 98	  .keyed_cksum = 1,
 99	},
100	/*
101	 * AES256
102	 */
103	{
104	  .etype = ENCTYPE_AES256_CTS_HMAC_SHA1_96,
105	  .ctype = CKSUMTYPE_HMAC_SHA1_96_AES256,
106	  .name = "aes256-cts",
107	  .encrypt_name = "cts(cbc(aes))",
108	  .cksum_name = "hmac(sha1)",
109	  .encrypt = krb5_encrypt,
110	  .decrypt = krb5_decrypt,
111	  .mk_key = gss_krb5_aes_make_key,
112	  .encrypt_v2 = gss_krb5_aes_encrypt,
113	  .decrypt_v2 = gss_krb5_aes_decrypt,
114	  .signalg = -1,
115	  .sealalg = -1,
116	  .keybytes = 32,
117	  .keylength = 32,
118	  .blocksize = 16,
119	  .conflen = 16,
120	  .cksumlength = 12,
121	  .keyed_cksum = 1,
122	},
123};
124
125static const int num_supported_enctypes =
126	ARRAY_SIZE(supported_gss_krb5_enctypes);
127
128static int
129supported_gss_krb5_enctype(int etype)
130{
131	int i;
132	for (i = 0; i < num_supported_enctypes; i++)
133		if (supported_gss_krb5_enctypes[i].etype == etype)
134			return 1;
135	return 0;
136}
137
138static const struct gss_krb5_enctype *
139get_gss_krb5_enctype(int etype)
140{
141	int i;
142	for (i = 0; i < num_supported_enctypes; i++)
143		if (supported_gss_krb5_enctypes[i].etype == etype)
144			return &supported_gss_krb5_enctypes[i];
145	return NULL;
146}
147
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
148static inline const void *
149get_key(const void *p, const void *end,
150	struct krb5_ctx *ctx, struct crypto_sync_skcipher **res)
151{
152	struct xdr_netobj	key;
153	int			alg;
154
155	p = simple_get_bytes(p, end, &alg, sizeof(alg));
156	if (IS_ERR(p))
157		goto out_err;
158
159	switch (alg) {
160	case ENCTYPE_DES_CBC_CRC:
161	case ENCTYPE_DES_CBC_MD4:
162	case ENCTYPE_DES_CBC_MD5:
163		/* Map all these key types to ENCTYPE_DES_CBC_RAW */
164		alg = ENCTYPE_DES_CBC_RAW;
165		break;
166	}
167
168	if (!supported_gss_krb5_enctype(alg)) {
169		printk(KERN_WARNING "gss_kerberos_mech: unsupported "
170			"encryption key algorithm %d\n", alg);
171		p = ERR_PTR(-EINVAL);
172		goto out_err;
173	}
174	p = simple_get_netobj(p, end, &key);
175	if (IS_ERR(p))
176		goto out_err;
177
178	*res = crypto_alloc_sync_skcipher(ctx->gk5e->encrypt_name, 0, 0);
 
179	if (IS_ERR(*res)) {
180		printk(KERN_WARNING "gss_kerberos_mech: unable to initialize "
181			"crypto algorithm %s\n", ctx->gk5e->encrypt_name);
182		*res = NULL;
183		goto out_err_free_key;
184	}
185	if (crypto_sync_skcipher_setkey(*res, key.data, key.len)) {
186		printk(KERN_WARNING "gss_kerberos_mech: error setting key for "
187			"crypto algorithm %s\n", ctx->gk5e->encrypt_name);
188		goto out_err_free_tfm;
189	}
190
191	kfree(key.data);
192	return p;
193
194out_err_free_tfm:
195	crypto_free_sync_skcipher(*res);
196out_err_free_key:
197	kfree(key.data);
198	p = ERR_PTR(-EINVAL);
199out_err:
200	return p;
201}
202
203static int
204gss_import_v1_context(const void *p, const void *end, struct krb5_ctx *ctx)
205{
206	u32 seq_send;
207	int tmp;
208	u32 time32;
209
210	p = simple_get_bytes(p, end, &ctx->initiate, sizeof(ctx->initiate));
211	if (IS_ERR(p))
212		goto out_err;
213
214	/* Old format supports only DES!  Any other enctype uses new format */
215	ctx->enctype = ENCTYPE_DES_CBC_RAW;
216
217	ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
218	if (ctx->gk5e == NULL) {
219		p = ERR_PTR(-EINVAL);
220		goto out_err;
221	}
222
223	/* The downcall format was designed before we completely understood
224	 * the uses of the context fields; so it includes some stuff we
225	 * just give some minimal sanity-checking, and some we ignore
226	 * completely (like the next twenty bytes): */
227	if (unlikely(p + 20 > end || p + 20 < p)) {
228		p = ERR_PTR(-EFAULT);
229		goto out_err;
230	}
231	p += 20;
232	p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
233	if (IS_ERR(p))
234		goto out_err;
235	if (tmp != SGN_ALG_DES_MAC_MD5) {
236		p = ERR_PTR(-ENOSYS);
237		goto out_err;
238	}
239	p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
240	if (IS_ERR(p))
241		goto out_err;
242	if (tmp != SEAL_ALG_DES) {
243		p = ERR_PTR(-ENOSYS);
244		goto out_err;
245	}
246	p = simple_get_bytes(p, end, &time32, sizeof(time32));
247	if (IS_ERR(p))
248		goto out_err;
249	/* unsigned 32-bit time overflows in year 2106 */
250	ctx->endtime = (time64_t)time32;
251	p = simple_get_bytes(p, end, &seq_send, sizeof(seq_send));
252	if (IS_ERR(p))
253		goto out_err;
254	atomic_set(&ctx->seq_send, seq_send);
255	p = simple_get_netobj(p, end, &ctx->mech_used);
256	if (IS_ERR(p))
257		goto out_err;
258	p = get_key(p, end, ctx, &ctx->enc);
259	if (IS_ERR(p))
260		goto out_err_free_mech;
261	p = get_key(p, end, ctx, &ctx->seq);
262	if (IS_ERR(p))
263		goto out_err_free_key1;
264	if (p != end) {
265		p = ERR_PTR(-EFAULT);
266		goto out_err_free_key2;
267	}
268
269	return 0;
270
271out_err_free_key2:
272	crypto_free_sync_skcipher(ctx->seq);
273out_err_free_key1:
274	crypto_free_sync_skcipher(ctx->enc);
275out_err_free_mech:
276	kfree(ctx->mech_used.data);
277out_err:
278	return PTR_ERR(p);
279}
280
281static struct crypto_sync_skcipher *
282context_v2_alloc_cipher(struct krb5_ctx *ctx, const char *cname, u8 *key)
283{
284	struct crypto_sync_skcipher *cp;
285
286	cp = crypto_alloc_sync_skcipher(cname, 0, 0);
287	if (IS_ERR(cp)) {
288		dprintk("gss_kerberos_mech: unable to initialize "
289			"crypto algorithm %s\n", cname);
290		return NULL;
291	}
292	if (crypto_sync_skcipher_setkey(cp, key, ctx->gk5e->keylength)) {
293		dprintk("gss_kerberos_mech: error setting key for "
294			"crypto algorithm %s\n", cname);
295		crypto_free_sync_skcipher(cp);
296		return NULL;
297	}
298	return cp;
299}
300
301static inline void
302set_cdata(u8 cdata[GSS_KRB5_K5CLENGTH], u32 usage, u8 seed)
303{
304	cdata[0] = (usage>>24)&0xff;
305	cdata[1] = (usage>>16)&0xff;
306	cdata[2] = (usage>>8)&0xff;
307	cdata[3] = usage&0xff;
308	cdata[4] = seed;
309}
310
311static int
312context_derive_keys_des3(struct krb5_ctx *ctx, gfp_t gfp_mask)
313{
314	struct xdr_netobj c, keyin, keyout;
315	u8 cdata[GSS_KRB5_K5CLENGTH];
316	u32 err;
317
318	c.len = GSS_KRB5_K5CLENGTH;
319	c.data = cdata;
320
321	keyin.data = ctx->Ksess;
322	keyin.len = ctx->gk5e->keylength;
323	keyout.len = ctx->gk5e->keylength;
324
325	/* seq uses the raw key */
326	ctx->seq = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
327					   ctx->Ksess);
328	if (ctx->seq == NULL)
329		goto out_err;
330
331	ctx->enc = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
332					   ctx->Ksess);
333	if (ctx->enc == NULL)
334		goto out_free_seq;
335
336	/* derive cksum */
337	set_cdata(cdata, KG_USAGE_SIGN, KEY_USAGE_SEED_CHECKSUM);
338	keyout.data = ctx->cksum;
339	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
340	if (err) {
341		dprintk("%s: Error %d deriving cksum key\n",
342			__func__, err);
343		goto out_free_enc;
344	}
345
346	return 0;
347
348out_free_enc:
349	crypto_free_sync_skcipher(ctx->enc);
350out_free_seq:
351	crypto_free_sync_skcipher(ctx->seq);
352out_err:
353	return -EINVAL;
354}
355
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
356static int
357context_derive_keys_new(struct krb5_ctx *ctx, gfp_t gfp_mask)
358{
359	struct xdr_netobj c, keyin, keyout;
360	u8 cdata[GSS_KRB5_K5CLENGTH];
361	u32 err;
362
363	c.len = GSS_KRB5_K5CLENGTH;
364	c.data = cdata;
365
366	keyin.data = ctx->Ksess;
367	keyin.len = ctx->gk5e->keylength;
368	keyout.len = ctx->gk5e->keylength;
369
370	/* initiator seal encryption */
371	set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
372	keyout.data = ctx->initiator_seal;
373	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
374	if (err) {
375		dprintk("%s: Error %d deriving initiator_seal key\n",
376			__func__, err);
377		goto out_err;
378	}
379	ctx->initiator_enc = context_v2_alloc_cipher(ctx,
380						     ctx->gk5e->encrypt_name,
381						     ctx->initiator_seal);
382	if (ctx->initiator_enc == NULL)
383		goto out_err;
384
385	/* acceptor seal encryption */
386	set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
387	keyout.data = ctx->acceptor_seal;
388	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
389	if (err) {
390		dprintk("%s: Error %d deriving acceptor_seal key\n",
391			__func__, err);
392		goto out_free_initiator_enc;
393	}
394	ctx->acceptor_enc = context_v2_alloc_cipher(ctx,
395						    ctx->gk5e->encrypt_name,
396						    ctx->acceptor_seal);
397	if (ctx->acceptor_enc == NULL)
398		goto out_free_initiator_enc;
399
400	/* initiator sign checksum */
401	set_cdata(cdata, KG_USAGE_INITIATOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
402	keyout.data = ctx->initiator_sign;
403	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
404	if (err) {
405		dprintk("%s: Error %d deriving initiator_sign key\n",
406			__func__, err);
407		goto out_free_acceptor_enc;
408	}
409
410	/* acceptor sign checksum */
411	set_cdata(cdata, KG_USAGE_ACCEPTOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
412	keyout.data = ctx->acceptor_sign;
413	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
414	if (err) {
415		dprintk("%s: Error %d deriving acceptor_sign key\n",
416			__func__, err);
417		goto out_free_acceptor_enc;
418	}
419
420	/* initiator seal integrity */
421	set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
422	keyout.data = ctx->initiator_integ;
423	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
424	if (err) {
425		dprintk("%s: Error %d deriving initiator_integ key\n",
426			__func__, err);
427		goto out_free_acceptor_enc;
428	}
429
430	/* acceptor seal integrity */
431	set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
432	keyout.data = ctx->acceptor_integ;
433	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
434	if (err) {
435		dprintk("%s: Error %d deriving acceptor_integ key\n",
436			__func__, err);
437		goto out_free_acceptor_enc;
438	}
439
440	switch (ctx->enctype) {
441	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
442	case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
443		ctx->initiator_enc_aux =
444			context_v2_alloc_cipher(ctx, "cbc(aes)",
445						ctx->initiator_seal);
446		if (ctx->initiator_enc_aux == NULL)
447			goto out_free_acceptor_enc;
448		ctx->acceptor_enc_aux =
449			context_v2_alloc_cipher(ctx, "cbc(aes)",
450						ctx->acceptor_seal);
451		if (ctx->acceptor_enc_aux == NULL) {
452			crypto_free_sync_skcipher(ctx->initiator_enc_aux);
453			goto out_free_acceptor_enc;
454		}
455	}
456
457	return 0;
458
459out_free_acceptor_enc:
460	crypto_free_sync_skcipher(ctx->acceptor_enc);
461out_free_initiator_enc:
462	crypto_free_sync_skcipher(ctx->initiator_enc);
463out_err:
464	return -EINVAL;
465}
466
467static int
468gss_import_v2_context(const void *p, const void *end, struct krb5_ctx *ctx,
469		gfp_t gfp_mask)
470{
471	u64 seq_send64;
472	int keylen;
473	u32 time32;
474
475	p = simple_get_bytes(p, end, &ctx->flags, sizeof(ctx->flags));
476	if (IS_ERR(p))
477		goto out_err;
478	ctx->initiate = ctx->flags & KRB5_CTX_FLAG_INITIATOR;
479
480	p = simple_get_bytes(p, end, &time32, sizeof(time32));
481	if (IS_ERR(p))
482		goto out_err;
483	/* unsigned 32-bit time overflows in year 2106 */
484	ctx->endtime = (time64_t)time32;
485	p = simple_get_bytes(p, end, &seq_send64, sizeof(seq_send64));
486	if (IS_ERR(p))
487		goto out_err;
488	atomic64_set(&ctx->seq_send64, seq_send64);
489	/* set seq_send for use by "older" enctypes */
490	atomic_set(&ctx->seq_send, seq_send64);
491	if (seq_send64 != atomic_read(&ctx->seq_send)) {
492		dprintk("%s: seq_send64 %llx, seq_send %x overflow?\n", __func__,
493			seq_send64, atomic_read(&ctx->seq_send));
494		p = ERR_PTR(-EINVAL);
495		goto out_err;
496	}
497	p = simple_get_bytes(p, end, &ctx->enctype, sizeof(ctx->enctype));
498	if (IS_ERR(p))
499		goto out_err;
500	/* Map ENCTYPE_DES3_CBC_SHA1 to ENCTYPE_DES3_CBC_RAW */
501	if (ctx->enctype == ENCTYPE_DES3_CBC_SHA1)
502		ctx->enctype = ENCTYPE_DES3_CBC_RAW;
503	ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
504	if (ctx->gk5e == NULL) {
505		dprintk("gss_kerberos_mech: unsupported krb5 enctype %u\n",
506			ctx->enctype);
507		p = ERR_PTR(-EINVAL);
508		goto out_err;
509	}
510	keylen = ctx->gk5e->keylength;
511
512	p = simple_get_bytes(p, end, ctx->Ksess, keylen);
513	if (IS_ERR(p))
514		goto out_err;
515
516	if (p != end) {
517		p = ERR_PTR(-EINVAL);
518		goto out_err;
519	}
520
521	ctx->mech_used.data = kmemdup(gss_kerberos_mech.gm_oid.data,
522				      gss_kerberos_mech.gm_oid.len, gfp_mask);
523	if (unlikely(ctx->mech_used.data == NULL)) {
524		p = ERR_PTR(-ENOMEM);
525		goto out_err;
526	}
527	ctx->mech_used.len = gss_kerberos_mech.gm_oid.len;
528
529	switch (ctx->enctype) {
530	case ENCTYPE_DES3_CBC_RAW:
531		return context_derive_keys_des3(ctx, gfp_mask);
 
 
532	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
533	case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
534		return context_derive_keys_new(ctx, gfp_mask);
535	default:
536		return -EINVAL;
537	}
538
539out_err:
540	return PTR_ERR(p);
541}
542
543static int
544gss_import_sec_context_kerberos(const void *p, size_t len,
545				struct gss_ctx *ctx_id,
546				time64_t *endtime,
547				gfp_t gfp_mask)
548{
549	const void *end = (const void *)((const char *)p + len);
550	struct  krb5_ctx *ctx;
551	int ret;
552
553	ctx = kzalloc(sizeof(*ctx), gfp_mask);
554	if (ctx == NULL)
555		return -ENOMEM;
556
557	if (len == 85)
558		ret = gss_import_v1_context(p, end, ctx);
559	else
560		ret = gss_import_v2_context(p, end, ctx, gfp_mask);
561
562	if (ret == 0) {
563		ctx_id->internal_ctx_id = ctx;
564		if (endtime)
565			*endtime = ctx->endtime;
566	} else
567		kfree(ctx);
568
569	dprintk("RPC:       %s: returning %d\n", __func__, ret);
570	return ret;
571}
572
573static void
574gss_delete_sec_context_kerberos(void *internal_ctx) {
575	struct krb5_ctx *kctx = internal_ctx;
576
577	crypto_free_sync_skcipher(kctx->seq);
578	crypto_free_sync_skcipher(kctx->enc);
579	crypto_free_sync_skcipher(kctx->acceptor_enc);
580	crypto_free_sync_skcipher(kctx->initiator_enc);
581	crypto_free_sync_skcipher(kctx->acceptor_enc_aux);
582	crypto_free_sync_skcipher(kctx->initiator_enc_aux);
583	kfree(kctx->mech_used.data);
584	kfree(kctx);
585}
586
587static const struct gss_api_ops gss_kerberos_ops = {
588	.gss_import_sec_context	= gss_import_sec_context_kerberos,
589	.gss_get_mic		= gss_get_mic_kerberos,
590	.gss_verify_mic		= gss_verify_mic_kerberos,
591	.gss_wrap		= gss_wrap_kerberos,
592	.gss_unwrap		= gss_unwrap_kerberos,
593	.gss_delete_sec_context	= gss_delete_sec_context_kerberos,
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 = KRB5_SUPPORTED_ENCTYPES,
635};
636
637static int __init init_kerberos_module(void)
638{
639	int status;
640
641	status = gss_mech_register(&gss_kerberos_mech);
642	if (status)
643		printk("Failed to register kerberos gss mechanism!\n");
644	return status;
645}
646
647static void __exit cleanup_kerberos_module(void)
648{
649	gss_mech_unregister(&gss_kerberos_mech);
650}
651
652MODULE_LICENSE("GPL");
653module_init(init_kerberos_module);
654module_exit(cleanup_kerberos_module);
v4.17
 
  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 <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>
 48
 
 
 49#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 50# define RPCDBG_FACILITY	RPCDBG_AUTH
 51#endif
 52
 53static struct gss_api_mech gss_kerberos_mech;	/* forward declaration */
 54
 55static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
 
 56	/*
 57	 * DES (All DES enctypes are mapped to the same gss functionality)
 58	 */
 59	{
 60	  .etype = ENCTYPE_DES_CBC_RAW,
 61	  .ctype = CKSUMTYPE_RSA_MD5,
 62	  .name = "des-cbc-crc",
 63	  .encrypt_name = "cbc(des)",
 64	  .cksum_name = "md5",
 65	  .encrypt = krb5_encrypt,
 66	  .decrypt = krb5_decrypt,
 67	  .mk_key = NULL,
 68	  .signalg = SGN_ALG_DES_MAC_MD5,
 69	  .sealalg = SEAL_ALG_DES,
 70	  .keybytes = 7,
 71	  .keylength = 8,
 72	  .blocksize = 8,
 73	  .conflen = 8,
 74	  .cksumlength = 8,
 75	  .keyed_cksum = 0,
 76	},
 77	/*
 78	 * RC4-HMAC
 79	 */
 80	{
 81	  .etype = ENCTYPE_ARCFOUR_HMAC,
 82	  .ctype = CKSUMTYPE_HMAC_MD5_ARCFOUR,
 83	  .name = "rc4-hmac",
 84	  .encrypt_name = "ecb(arc4)",
 85	  .cksum_name = "hmac(md5)",
 86	  .encrypt = krb5_encrypt,
 87	  .decrypt = krb5_decrypt,
 88	  .mk_key = NULL,
 89	  .signalg = SGN_ALG_HMAC_MD5,
 90	  .sealalg = SEAL_ALG_MICROSOFT_RC4,
 91	  .keybytes = 16,
 92	  .keylength = 16,
 93	  .blocksize = 1,
 94	  .conflen = 8,
 95	  .cksumlength = 8,
 96	  .keyed_cksum = 1,
 97	},
 98	/*
 99	 * 3DES
100	 */
101	{
102	  .etype = ENCTYPE_DES3_CBC_RAW,
103	  .ctype = CKSUMTYPE_HMAC_SHA1_DES3,
104	  .name = "des3-hmac-sha1",
105	  .encrypt_name = "cbc(des3_ede)",
106	  .cksum_name = "hmac(sha1)",
107	  .encrypt = krb5_encrypt,
108	  .decrypt = krb5_decrypt,
109	  .mk_key = gss_krb5_des3_make_key,
110	  .signalg = SGN_ALG_HMAC_SHA1_DES3_KD,
111	  .sealalg = SEAL_ALG_DES3KD,
112	  .keybytes = 21,
113	  .keylength = 24,
114	  .blocksize = 8,
115	  .conflen = 8,
116	  .cksumlength = 20,
117	  .keyed_cksum = 1,
118	},
119	/*
120	 * AES128
121	 */
122	{
123	  .etype = ENCTYPE_AES128_CTS_HMAC_SHA1_96,
124	  .ctype = CKSUMTYPE_HMAC_SHA1_96_AES128,
125	  .name = "aes128-cts",
126	  .encrypt_name = "cts(cbc(aes))",
127	  .cksum_name = "hmac(sha1)",
128	  .encrypt = krb5_encrypt,
129	  .decrypt = krb5_decrypt,
130	  .mk_key = gss_krb5_aes_make_key,
131	  .encrypt_v2 = gss_krb5_aes_encrypt,
132	  .decrypt_v2 = gss_krb5_aes_decrypt,
133	  .signalg = -1,
134	  .sealalg = -1,
135	  .keybytes = 16,
136	  .keylength = 16,
137	  .blocksize = 16,
138	  .conflen = 16,
139	  .cksumlength = 12,
140	  .keyed_cksum = 1,
141	},
142	/*
143	 * AES256
144	 */
145	{
146	  .etype = ENCTYPE_AES256_CTS_HMAC_SHA1_96,
147	  .ctype = CKSUMTYPE_HMAC_SHA1_96_AES256,
148	  .name = "aes256-cts",
149	  .encrypt_name = "cts(cbc(aes))",
150	  .cksum_name = "hmac(sha1)",
151	  .encrypt = krb5_encrypt,
152	  .decrypt = krb5_decrypt,
153	  .mk_key = gss_krb5_aes_make_key,
154	  .encrypt_v2 = gss_krb5_aes_encrypt,
155	  .decrypt_v2 = gss_krb5_aes_decrypt,
156	  .signalg = -1,
157	  .sealalg = -1,
158	  .keybytes = 32,
159	  .keylength = 32,
160	  .blocksize = 16,
161	  .conflen = 16,
162	  .cksumlength = 12,
163	  .keyed_cksum = 1,
164	},
165};
166
167static const int num_supported_enctypes =
168	ARRAY_SIZE(supported_gss_krb5_enctypes);
169
170static int
171supported_gss_krb5_enctype(int etype)
172{
173	int i;
174	for (i = 0; i < num_supported_enctypes; i++)
175		if (supported_gss_krb5_enctypes[i].etype == etype)
176			return 1;
177	return 0;
178}
179
180static const struct gss_krb5_enctype *
181get_gss_krb5_enctype(int etype)
182{
183	int i;
184	for (i = 0; i < num_supported_enctypes; i++)
185		if (supported_gss_krb5_enctypes[i].etype == etype)
186			return &supported_gss_krb5_enctypes[i];
187	return NULL;
188}
189
190static const void *
191simple_get_bytes(const void *p, const void *end, void *res, int len)
192{
193	const void *q = (const void *)((const char *)p + len);
194	if (unlikely(q > end || q < p))
195		return ERR_PTR(-EFAULT);
196	memcpy(res, p, len);
197	return q;
198}
199
200static const void *
201simple_get_netobj(const void *p, const void *end, struct xdr_netobj *res)
202{
203	const void *q;
204	unsigned int len;
205
206	p = simple_get_bytes(p, end, &len, sizeof(len));
207	if (IS_ERR(p))
208		return p;
209	q = (const void *)((const char *)p + len);
210	if (unlikely(q > end || q < p))
211		return ERR_PTR(-EFAULT);
212	res->data = kmemdup(p, len, GFP_NOFS);
213	if (unlikely(res->data == NULL))
214		return ERR_PTR(-ENOMEM);
215	res->len = len;
216	return q;
217}
218
219static inline const void *
220get_key(const void *p, const void *end,
221	struct krb5_ctx *ctx, struct crypto_skcipher **res)
222{
223	struct xdr_netobj	key;
224	int			alg;
225
226	p = simple_get_bytes(p, end, &alg, sizeof(alg));
227	if (IS_ERR(p))
228		goto out_err;
229
230	switch (alg) {
231	case ENCTYPE_DES_CBC_CRC:
232	case ENCTYPE_DES_CBC_MD4:
233	case ENCTYPE_DES_CBC_MD5:
234		/* Map all these key types to ENCTYPE_DES_CBC_RAW */
235		alg = ENCTYPE_DES_CBC_RAW;
236		break;
237	}
238
239	if (!supported_gss_krb5_enctype(alg)) {
240		printk(KERN_WARNING "gss_kerberos_mech: unsupported "
241			"encryption key algorithm %d\n", alg);
242		p = ERR_PTR(-EINVAL);
243		goto out_err;
244	}
245	p = simple_get_netobj(p, end, &key);
246	if (IS_ERR(p))
247		goto out_err;
248
249	*res = crypto_alloc_skcipher(ctx->gk5e->encrypt_name, 0,
250							CRYPTO_ALG_ASYNC);
251	if (IS_ERR(*res)) {
252		printk(KERN_WARNING "gss_kerberos_mech: unable to initialize "
253			"crypto algorithm %s\n", ctx->gk5e->encrypt_name);
254		*res = NULL;
255		goto out_err_free_key;
256	}
257	if (crypto_skcipher_setkey(*res, key.data, key.len)) {
258		printk(KERN_WARNING "gss_kerberos_mech: error setting key for "
259			"crypto algorithm %s\n", ctx->gk5e->encrypt_name);
260		goto out_err_free_tfm;
261	}
262
263	kfree(key.data);
264	return p;
265
266out_err_free_tfm:
267	crypto_free_skcipher(*res);
268out_err_free_key:
269	kfree(key.data);
270	p = ERR_PTR(-EINVAL);
271out_err:
272	return p;
273}
274
275static int
276gss_import_v1_context(const void *p, const void *end, struct krb5_ctx *ctx)
277{
 
278	int tmp;
 
279
280	p = simple_get_bytes(p, end, &ctx->initiate, sizeof(ctx->initiate));
281	if (IS_ERR(p))
282		goto out_err;
283
284	/* Old format supports only DES!  Any other enctype uses new format */
285	ctx->enctype = ENCTYPE_DES_CBC_RAW;
286
287	ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
288	if (ctx->gk5e == NULL) {
289		p = ERR_PTR(-EINVAL);
290		goto out_err;
291	}
292
293	/* The downcall format was designed before we completely understood
294	 * the uses of the context fields; so it includes some stuff we
295	 * just give some minimal sanity-checking, and some we ignore
296	 * completely (like the next twenty bytes): */
297	if (unlikely(p + 20 > end || p + 20 < p)) {
298		p = ERR_PTR(-EFAULT);
299		goto out_err;
300	}
301	p += 20;
302	p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
303	if (IS_ERR(p))
304		goto out_err;
305	if (tmp != SGN_ALG_DES_MAC_MD5) {
306		p = ERR_PTR(-ENOSYS);
307		goto out_err;
308	}
309	p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
310	if (IS_ERR(p))
311		goto out_err;
312	if (tmp != SEAL_ALG_DES) {
313		p = ERR_PTR(-ENOSYS);
314		goto out_err;
315	}
316	p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
317	if (IS_ERR(p))
318		goto out_err;
319	p = simple_get_bytes(p, end, &ctx->seq_send, sizeof(ctx->seq_send));
 
 
320	if (IS_ERR(p))
321		goto out_err;
 
322	p = simple_get_netobj(p, end, &ctx->mech_used);
323	if (IS_ERR(p))
324		goto out_err;
325	p = get_key(p, end, ctx, &ctx->enc);
326	if (IS_ERR(p))
327		goto out_err_free_mech;
328	p = get_key(p, end, ctx, &ctx->seq);
329	if (IS_ERR(p))
330		goto out_err_free_key1;
331	if (p != end) {
332		p = ERR_PTR(-EFAULT);
333		goto out_err_free_key2;
334	}
335
336	return 0;
337
338out_err_free_key2:
339	crypto_free_skcipher(ctx->seq);
340out_err_free_key1:
341	crypto_free_skcipher(ctx->enc);
342out_err_free_mech:
343	kfree(ctx->mech_used.data);
344out_err:
345	return PTR_ERR(p);
346}
347
348static struct crypto_skcipher *
349context_v2_alloc_cipher(struct krb5_ctx *ctx, const char *cname, u8 *key)
350{
351	struct crypto_skcipher *cp;
352
353	cp = crypto_alloc_skcipher(cname, 0, CRYPTO_ALG_ASYNC);
354	if (IS_ERR(cp)) {
355		dprintk("gss_kerberos_mech: unable to initialize "
356			"crypto algorithm %s\n", cname);
357		return NULL;
358	}
359	if (crypto_skcipher_setkey(cp, key, ctx->gk5e->keylength)) {
360		dprintk("gss_kerberos_mech: error setting key for "
361			"crypto algorithm %s\n", cname);
362		crypto_free_skcipher(cp);
363		return NULL;
364	}
365	return cp;
366}
367
368static inline void
369set_cdata(u8 cdata[GSS_KRB5_K5CLENGTH], u32 usage, u8 seed)
370{
371	cdata[0] = (usage>>24)&0xff;
372	cdata[1] = (usage>>16)&0xff;
373	cdata[2] = (usage>>8)&0xff;
374	cdata[3] = usage&0xff;
375	cdata[4] = seed;
376}
377
378static int
379context_derive_keys_des3(struct krb5_ctx *ctx, gfp_t gfp_mask)
380{
381	struct xdr_netobj c, keyin, keyout;
382	u8 cdata[GSS_KRB5_K5CLENGTH];
383	u32 err;
384
385	c.len = GSS_KRB5_K5CLENGTH;
386	c.data = cdata;
387
388	keyin.data = ctx->Ksess;
389	keyin.len = ctx->gk5e->keylength;
390	keyout.len = ctx->gk5e->keylength;
391
392	/* seq uses the raw key */
393	ctx->seq = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
394					   ctx->Ksess);
395	if (ctx->seq == NULL)
396		goto out_err;
397
398	ctx->enc = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
399					   ctx->Ksess);
400	if (ctx->enc == NULL)
401		goto out_free_seq;
402
403	/* derive cksum */
404	set_cdata(cdata, KG_USAGE_SIGN, KEY_USAGE_SEED_CHECKSUM);
405	keyout.data = ctx->cksum;
406	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
407	if (err) {
408		dprintk("%s: Error %d deriving cksum key\n",
409			__func__, err);
410		goto out_free_enc;
411	}
412
413	return 0;
414
415out_free_enc:
416	crypto_free_skcipher(ctx->enc);
417out_free_seq:
418	crypto_free_skcipher(ctx->seq);
419out_err:
420	return -EINVAL;
421}
422
423/*
424 * Note that RC4 depends on deriving keys using the sequence
425 * number or the checksum of a token.  Therefore, the final keys
426 * cannot be calculated until the token is being constructed!
427 */
428static int
429context_derive_keys_rc4(struct krb5_ctx *ctx)
430{
431	struct crypto_shash *hmac;
432	char sigkeyconstant[] = "signaturekey";
433	int slen = strlen(sigkeyconstant) + 1;	/* include null terminator */
434	struct shash_desc *desc;
435	int err;
436
437	dprintk("RPC:       %s: entered\n", __func__);
438	/*
439	 * derive cksum (aka Ksign) key
440	 */
441	hmac = crypto_alloc_shash(ctx->gk5e->cksum_name, 0, 0);
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_shash_setkey(hmac, ctx->Ksess, ctx->gk5e->keylength);
450	if (err)
451		goto out_err_free_hmac;
452
453
454	desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(hmac), GFP_NOFS);
455	if (!desc) {
456		dprintk("%s: failed to allocate hash descriptor for '%s'\n",
457			__func__, ctx->gk5e->cksum_name);
458		err = -ENOMEM;
459		goto out_err_free_hmac;
460	}
461
462	desc->tfm = hmac;
463	desc->flags = 0;
464
465	err = crypto_shash_digest(desc, sigkeyconstant, slen, ctx->cksum);
466	kzfree(desc);
467	if (err)
468		goto out_err_free_hmac;
469	/*
470	 * allocate hash, and skciphers for data and seqnum encryption
471	 */
472	ctx->enc = crypto_alloc_skcipher(ctx->gk5e->encrypt_name, 0,
473					 CRYPTO_ALG_ASYNC);
474	if (IS_ERR(ctx->enc)) {
475		err = PTR_ERR(ctx->enc);
476		goto out_err_free_hmac;
477	}
478
479	ctx->seq = crypto_alloc_skcipher(ctx->gk5e->encrypt_name, 0,
480					 CRYPTO_ALG_ASYNC);
481	if (IS_ERR(ctx->seq)) {
482		crypto_free_skcipher(ctx->enc);
483		err = PTR_ERR(ctx->seq);
484		goto out_err_free_hmac;
485	}
486
487	dprintk("RPC:       %s: returning success\n", __func__);
488
489	err = 0;
490
491out_err_free_hmac:
492	crypto_free_shash(hmac);
493out_err:
494	dprintk("RPC:       %s: returning %d\n", __func__, err);
495	return err;
496}
497
498static int
499context_derive_keys_new(struct krb5_ctx *ctx, gfp_t gfp_mask)
500{
501	struct xdr_netobj c, keyin, keyout;
502	u8 cdata[GSS_KRB5_K5CLENGTH];
503	u32 err;
504
505	c.len = GSS_KRB5_K5CLENGTH;
506	c.data = cdata;
507
508	keyin.data = ctx->Ksess;
509	keyin.len = ctx->gk5e->keylength;
510	keyout.len = ctx->gk5e->keylength;
511
512	/* initiator seal encryption */
513	set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
514	keyout.data = ctx->initiator_seal;
515	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
516	if (err) {
517		dprintk("%s: Error %d deriving initiator_seal key\n",
518			__func__, err);
519		goto out_err;
520	}
521	ctx->initiator_enc = context_v2_alloc_cipher(ctx,
522						     ctx->gk5e->encrypt_name,
523						     ctx->initiator_seal);
524	if (ctx->initiator_enc == NULL)
525		goto out_err;
526
527	/* acceptor seal encryption */
528	set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
529	keyout.data = ctx->acceptor_seal;
530	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
531	if (err) {
532		dprintk("%s: Error %d deriving acceptor_seal key\n",
533			__func__, err);
534		goto out_free_initiator_enc;
535	}
536	ctx->acceptor_enc = context_v2_alloc_cipher(ctx,
537						    ctx->gk5e->encrypt_name,
538						    ctx->acceptor_seal);
539	if (ctx->acceptor_enc == NULL)
540		goto out_free_initiator_enc;
541
542	/* initiator sign checksum */
543	set_cdata(cdata, KG_USAGE_INITIATOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
544	keyout.data = ctx->initiator_sign;
545	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
546	if (err) {
547		dprintk("%s: Error %d deriving initiator_sign key\n",
548			__func__, err);
549		goto out_free_acceptor_enc;
550	}
551
552	/* acceptor sign checksum */
553	set_cdata(cdata, KG_USAGE_ACCEPTOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
554	keyout.data = ctx->acceptor_sign;
555	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
556	if (err) {
557		dprintk("%s: Error %d deriving acceptor_sign key\n",
558			__func__, err);
559		goto out_free_acceptor_enc;
560	}
561
562	/* initiator seal integrity */
563	set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
564	keyout.data = ctx->initiator_integ;
565	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
566	if (err) {
567		dprintk("%s: Error %d deriving initiator_integ key\n",
568			__func__, err);
569		goto out_free_acceptor_enc;
570	}
571
572	/* acceptor seal integrity */
573	set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
574	keyout.data = ctx->acceptor_integ;
575	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
576	if (err) {
577		dprintk("%s: Error %d deriving acceptor_integ key\n",
578			__func__, err);
579		goto out_free_acceptor_enc;
580	}
581
582	switch (ctx->enctype) {
583	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
584	case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
585		ctx->initiator_enc_aux =
586			context_v2_alloc_cipher(ctx, "cbc(aes)",
587						ctx->initiator_seal);
588		if (ctx->initiator_enc_aux == NULL)
589			goto out_free_acceptor_enc;
590		ctx->acceptor_enc_aux =
591			context_v2_alloc_cipher(ctx, "cbc(aes)",
592						ctx->acceptor_seal);
593		if (ctx->acceptor_enc_aux == NULL) {
594			crypto_free_skcipher(ctx->initiator_enc_aux);
595			goto out_free_acceptor_enc;
596		}
597	}
598
599	return 0;
600
601out_free_acceptor_enc:
602	crypto_free_skcipher(ctx->acceptor_enc);
603out_free_initiator_enc:
604	crypto_free_skcipher(ctx->initiator_enc);
605out_err:
606	return -EINVAL;
607}
608
609static int
610gss_import_v2_context(const void *p, const void *end, struct krb5_ctx *ctx,
611		gfp_t gfp_mask)
612{
 
613	int keylen;
 
614
615	p = simple_get_bytes(p, end, &ctx->flags, sizeof(ctx->flags));
616	if (IS_ERR(p))
617		goto out_err;
618	ctx->initiate = ctx->flags & KRB5_CTX_FLAG_INITIATOR;
619
620	p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
621	if (IS_ERR(p))
622		goto out_err;
623	p = simple_get_bytes(p, end, &ctx->seq_send64, sizeof(ctx->seq_send64));
 
 
624	if (IS_ERR(p))
625		goto out_err;
 
626	/* set seq_send for use by "older" enctypes */
627	ctx->seq_send = ctx->seq_send64;
628	if (ctx->seq_send64 != ctx->seq_send) {
629		dprintk("%s: seq_send64 %lx, seq_send %x overflow?\n", __func__,
630			(unsigned long)ctx->seq_send64, ctx->seq_send);
631		p = ERR_PTR(-EINVAL);
632		goto out_err;
633	}
634	p = simple_get_bytes(p, end, &ctx->enctype, sizeof(ctx->enctype));
635	if (IS_ERR(p))
636		goto out_err;
637	/* Map ENCTYPE_DES3_CBC_SHA1 to ENCTYPE_DES3_CBC_RAW */
638	if (ctx->enctype == ENCTYPE_DES3_CBC_SHA1)
639		ctx->enctype = ENCTYPE_DES3_CBC_RAW;
640	ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
641	if (ctx->gk5e == NULL) {
642		dprintk("gss_kerberos_mech: unsupported krb5 enctype %u\n",
643			ctx->enctype);
644		p = ERR_PTR(-EINVAL);
645		goto out_err;
646	}
647	keylen = ctx->gk5e->keylength;
648
649	p = simple_get_bytes(p, end, ctx->Ksess, keylen);
650	if (IS_ERR(p))
651		goto out_err;
652
653	if (p != end) {
654		p = ERR_PTR(-EINVAL);
655		goto out_err;
656	}
657
658	ctx->mech_used.data = kmemdup(gss_kerberos_mech.gm_oid.data,
659				      gss_kerberos_mech.gm_oid.len, gfp_mask);
660	if (unlikely(ctx->mech_used.data == NULL)) {
661		p = ERR_PTR(-ENOMEM);
662		goto out_err;
663	}
664	ctx->mech_used.len = gss_kerberos_mech.gm_oid.len;
665
666	switch (ctx->enctype) {
667	case ENCTYPE_DES3_CBC_RAW:
668		return context_derive_keys_des3(ctx, gfp_mask);
669	case ENCTYPE_ARCFOUR_HMAC:
670		return context_derive_keys_rc4(ctx);
671	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
672	case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
673		return context_derive_keys_new(ctx, gfp_mask);
674	default:
675		return -EINVAL;
676	}
677
678out_err:
679	return PTR_ERR(p);
680}
681
682static int
683gss_import_sec_context_kerberos(const void *p, size_t len,
684				struct gss_ctx *ctx_id,
685				time_t *endtime,
686				gfp_t gfp_mask)
687{
688	const void *end = (const void *)((const char *)p + len);
689	struct  krb5_ctx *ctx;
690	int ret;
691
692	ctx = kzalloc(sizeof(*ctx), gfp_mask);
693	if (ctx == NULL)
694		return -ENOMEM;
695
696	if (len == 85)
697		ret = gss_import_v1_context(p, end, ctx);
698	else
699		ret = gss_import_v2_context(p, end, ctx, gfp_mask);
700
701	if (ret == 0) {
702		ctx_id->internal_ctx_id = ctx;
703		if (endtime)
704			*endtime = ctx->endtime;
705	} else
706		kfree(ctx);
707
708	dprintk("RPC:       %s: returning %d\n", __func__, ret);
709	return ret;
710}
711
712static void
713gss_delete_sec_context_kerberos(void *internal_ctx) {
714	struct krb5_ctx *kctx = internal_ctx;
715
716	crypto_free_skcipher(kctx->seq);
717	crypto_free_skcipher(kctx->enc);
718	crypto_free_skcipher(kctx->acceptor_enc);
719	crypto_free_skcipher(kctx->initiator_enc);
720	crypto_free_skcipher(kctx->acceptor_enc_aux);
721	crypto_free_skcipher(kctx->initiator_enc_aux);
722	kfree(kctx->mech_used.data);
723	kfree(kctx);
724}
725
726static const struct gss_api_ops gss_kerberos_ops = {
727	.gss_import_sec_context	= gss_import_sec_context_kerberos,
728	.gss_get_mic		= gss_get_mic_kerberos,
729	.gss_verify_mic		= gss_verify_mic_kerberos,
730	.gss_wrap		= gss_wrap_kerberos,
731	.gss_unwrap		= gss_unwrap_kerberos,
732	.gss_delete_sec_context	= gss_delete_sec_context_kerberos,
733};
734
735static struct pf_desc gss_kerberos_pfs[] = {
736	[0] = {
737		.pseudoflavor = RPC_AUTH_GSS_KRB5,
738		.qop = GSS_C_QOP_DEFAULT,
739		.service = RPC_GSS_SVC_NONE,
740		.name = "krb5",
741	},
742	[1] = {
743		.pseudoflavor = RPC_AUTH_GSS_KRB5I,
744		.qop = GSS_C_QOP_DEFAULT,
745		.service = RPC_GSS_SVC_INTEGRITY,
746		.name = "krb5i",
747		.datatouch = true,
748	},
749	[2] = {
750		.pseudoflavor = RPC_AUTH_GSS_KRB5P,
751		.qop = GSS_C_QOP_DEFAULT,
752		.service = RPC_GSS_SVC_PRIVACY,
753		.name = "krb5p",
754		.datatouch = true,
755	},
756};
757
758MODULE_ALIAS("rpc-auth-gss-krb5");
759MODULE_ALIAS("rpc-auth-gss-krb5i");
760MODULE_ALIAS("rpc-auth-gss-krb5p");
761MODULE_ALIAS("rpc-auth-gss-390003");
762MODULE_ALIAS("rpc-auth-gss-390004");
763MODULE_ALIAS("rpc-auth-gss-390005");
764MODULE_ALIAS("rpc-auth-gss-1.2.840.113554.1.2.2");
765
766static struct gss_api_mech gss_kerberos_mech = {
767	.gm_name	= "krb5",
768	.gm_owner	= THIS_MODULE,
769	.gm_oid		= { 9, "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02" },
770	.gm_ops		= &gss_kerberos_ops,
771	.gm_pf_num	= ARRAY_SIZE(gss_kerberos_pfs),
772	.gm_pfs		= gss_kerberos_pfs,
773	.gm_upcall_enctypes = KRB5_SUPPORTED_ENCTYPES,
774};
775
776static int __init init_kerberos_module(void)
777{
778	int status;
779
780	status = gss_mech_register(&gss_kerberos_mech);
781	if (status)
782		printk("Failed to register kerberos gss mechanism!\n");
783	return status;
784}
785
786static void __exit cleanup_kerberos_module(void)
787{
788	gss_mech_unregister(&gss_kerberos_mech);
789}
790
791MODULE_LICENSE("GPL");
792module_init(init_kerberos_module);
793module_exit(cleanup_kerberos_module);