1/*
2 * Copyright (C) 2004-2007, 2010  Internet Systems Consortium, Inc. ("ISC")
3 * Copyright (C) 2002, 2003  Internet Software Consortium.
4 *
5 * Permission to use, copy, modify, and/or distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
10 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15 * PERFORMANCE OF THIS SOFTWARE.
16 */
17
18/* $Id: ds.c,v 1.13 2010/12/23 23:47:08 tbox Exp $ */
19
20/*! \file */
21
22#include <config.h>
23
24#include <string.h>
25
26#include <isc/buffer.h>
27#include <isc/region.h>
28#include <isc/sha1.h>
29#include <isc/sha2.h>
30#include <isc/util.h>
31
32#include <dns/ds.h>
33#include <dns/fixedname.h>
34#include <dns/name.h>
35#include <dns/rdata.h>
36#include <dns/rdatastruct.h>
37#include <dns/result.h>
38
39#include <dst/dst.h>
40
41#ifdef HAVE_OPENSSL_GOST
42#include <dst/result.h>
43#include <openssl/evp.h>
44
45extern const EVP_MD * EVP_gost(void);
46#endif
47
48isc_result_t
49dns_ds_buildrdata(dns_name_t *owner, dns_rdata_t *key,
50		  unsigned int digest_type, unsigned char *buffer,
51		  dns_rdata_t *rdata)
52{
53	dns_fixedname_t fname;
54	dns_name_t *name;
55	unsigned char digest[ISC_SHA256_DIGESTLENGTH];
56	isc_region_t r;
57	isc_buffer_t b;
58	dns_rdata_ds_t ds;
59	isc_sha1_t sha1;
60	isc_sha256_t sha256;
61#ifdef HAVE_OPENSSL_GOST
62	EVP_MD_CTX ctx;
63	const EVP_MD *md;
64#endif
65
66	REQUIRE(key != NULL);
67	REQUIRE(key->type == dns_rdatatype_dnskey);
68
69	if (!dns_ds_digest_supported(digest_type))
70		return (ISC_R_NOTIMPLEMENTED);
71
72	dns_fixedname_init(&fname);
73	name = dns_fixedname_name(&fname);
74	(void)dns_name_downcase(owner, name, NULL);
75
76	memset(buffer, 0, DNS_DS_BUFFERSIZE);
77	isc_buffer_init(&b, buffer, DNS_DS_BUFFERSIZE);
78
79	switch (digest_type) {
80	case DNS_DSDIGEST_SHA1:
81		isc_sha1_init(&sha1);
82		dns_name_toregion(name, &r);
83		isc_sha1_update(&sha1, r.base, r.length);
84		dns_rdata_toregion(key, &r);
85		INSIST(r.length >= 4);
86		isc_sha1_update(&sha1, r.base, r.length);
87		isc_sha1_final(&sha1, digest);
88		break;
89#ifdef HAVE_OPENSSL_GOST
90#define CHECK(x)					\
91	if ((x) != 1) {					\
92		EVP_MD_CTX_cleanup(&ctx);		\
93		return (DST_R_OPENSSLFAILURE);		\
94	}
95
96	case DNS_DSDIGEST_GOST:
97		md = EVP_gost();
98		if (md == NULL)
99			return (DST_R_OPENSSLFAILURE);
100		EVP_MD_CTX_init(&ctx);
101		CHECK(EVP_DigestInit(&ctx, md));
102		dns_name_toregion(name, &r);
103		CHECK(EVP_DigestUpdate(&ctx,
104				       (const void *) r.base,
105				       (size_t) r.length));
106		dns_rdata_toregion(key, &r);
107		INSIST(r.length >= 4);
108		CHECK(EVP_DigestUpdate(&ctx,
109				       (const void *) r.base,
110				       (size_t) r.length));
111		CHECK(EVP_DigestFinal(&ctx, digest, NULL));
112		break;
113#endif
114	default:
115		isc_sha256_init(&sha256);
116		dns_name_toregion(name, &r);
117		isc_sha256_update(&sha256, r.base, r.length);
118		dns_rdata_toregion(key, &r);
119		INSIST(r.length >= 4);
120		isc_sha256_update(&sha256, r.base, r.length);
121		isc_sha256_final(digest, &sha256);
122		break;
123	}
124
125	ds.mctx = NULL;
126	ds.common.rdclass = key->rdclass;
127	ds.common.rdtype = dns_rdatatype_ds;
128	ds.algorithm = r.base[3];
129	ds.key_tag = dst_region_computeid(&r, ds.algorithm);
130	ds.digest_type = digest_type;
131	switch (digest_type) {
132	case DNS_DSDIGEST_SHA1:
133		ds.length = ISC_SHA1_DIGESTLENGTH;
134		break;
135#ifdef HAVE_OPENSSL_GOST
136	case DNS_DSDIGEST_GOST:
137		ds.length = ISC_GOST_DIGESTLENGTH;
138		break;
139#endif
140	default:
141		ds.length = ISC_SHA256_DIGESTLENGTH;
142		break;
143	}
144	ds.digest = digest;
145
146	return (dns_rdata_fromstruct(rdata, key->rdclass, dns_rdatatype_ds,
147				     &ds, &b));
148}
149
150isc_boolean_t
151dns_ds_digest_supported(unsigned int digest_type) {
152#ifdef HAVE_OPENSSL_GOST
153	return  (ISC_TF(digest_type == DNS_DSDIGEST_SHA1 ||
154			digest_type == DNS_DSDIGEST_SHA256 ||
155			digest_type == DNS_DSDIGEST_GOST));
156#else
157	return  (ISC_TF(digest_type == DNS_DSDIGEST_SHA1 ||
158			digest_type == DNS_DSDIGEST_SHA256));
159#endif
160}
161