xref: /netbsd/external/mpl/bind/dist/bin/named/tsigconf.c (revision 9742fdb4)
1 /*	$NetBSD: tsigconf.c,v 1.4 2020/05/24 19:46:12 christos Exp $	*/
2 
3 /*
4  * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
5  *
6  * This Source Code Form is subject to the terms of the Mozilla Public
7  * License, v. 2.0. If a copy of the MPL was not distributed with this
8  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
9  *
10  * See the COPYRIGHT file distributed with this work for additional
11  * information regarding copyright ownership.
12  */
13 
14 /*! \file */
15 
16 #include <inttypes.h>
17 
18 #include <isc/base64.h>
19 #include <isc/buffer.h>
20 #include <isc/mem.h>
21 #include <isc/string.h>
22 #include <isc/util.h>
23 
24 #include <dns/result.h>
25 #include <dns/tsig.h>
26 
27 #include <isccfg/cfg.h>
28 
29 #include <named/config.h>
30 #include <named/log.h>
31 #include <named/tsigconf.h>
32 
33 static isc_result_t
34 add_initial_keys(const cfg_obj_t *list, dns_tsig_keyring_t *ring,
35 		 isc_mem_t *mctx) {
36 	dns_tsigkey_t *tsigkey = NULL;
37 	const cfg_listelt_t *element;
38 	const cfg_obj_t *key = NULL;
39 	const char *keyid = NULL;
40 	unsigned char *secret = NULL;
41 	int secretalloc = 0;
42 	int secretlen = 0;
43 	isc_result_t ret;
44 	isc_stdtime_t now;
45 	uint16_t bits;
46 
47 	for (element = cfg_list_first(list); element != NULL;
48 	     element = cfg_list_next(element))
49 	{
50 		const cfg_obj_t *algobj = NULL;
51 		const cfg_obj_t *secretobj = NULL;
52 		dns_name_t keyname;
53 		const dns_name_t *alg;
54 		const char *algstr;
55 		char keynamedata[1024];
56 		isc_buffer_t keynamesrc, keynamebuf;
57 		const char *secretstr;
58 		isc_buffer_t secretbuf;
59 
60 		key = cfg_listelt_value(element);
61 		keyid = cfg_obj_asstring(cfg_map_getname(key));
62 
63 		algobj = NULL;
64 		secretobj = NULL;
65 		(void)cfg_map_get(key, "algorithm", &algobj);
66 		(void)cfg_map_get(key, "secret", &secretobj);
67 		INSIST(algobj != NULL && secretobj != NULL);
68 
69 		/*
70 		 * Create the key name.
71 		 */
72 		dns_name_init(&keyname, NULL);
73 		isc_buffer_constinit(&keynamesrc, keyid, strlen(keyid));
74 		isc_buffer_add(&keynamesrc, strlen(keyid));
75 		isc_buffer_init(&keynamebuf, keynamedata, sizeof(keynamedata));
76 		ret = dns_name_fromtext(&keyname, &keynamesrc, dns_rootname,
77 					DNS_NAME_DOWNCASE, &keynamebuf);
78 		if (ret != ISC_R_SUCCESS) {
79 			goto failure;
80 		}
81 
82 		/*
83 		 * Create the algorithm.
84 		 */
85 		algstr = cfg_obj_asstring(algobj);
86 		if (named_config_getkeyalgorithm(algstr, &alg, &bits) !=
87 		    ISC_R_SUCCESS) {
88 			cfg_obj_log(algobj, named_g_lctx, ISC_LOG_ERROR,
89 				    "key '%s': has a "
90 				    "unsupported algorithm '%s'",
91 				    keyid, algstr);
92 			ret = DNS_R_BADALG;
93 			goto failure;
94 		}
95 
96 		secretstr = cfg_obj_asstring(secretobj);
97 		secretalloc = secretlen = strlen(secretstr) * 3 / 4;
98 		secret = isc_mem_get(mctx, secretlen);
99 		isc_buffer_init(&secretbuf, secret, secretlen);
100 		ret = isc_base64_decodestring(secretstr, &secretbuf);
101 		if (ret != ISC_R_SUCCESS) {
102 			goto failure;
103 		}
104 		secretlen = isc_buffer_usedlength(&secretbuf);
105 
106 		isc_stdtime_get(&now);
107 		ret = dns_tsigkey_create(&keyname, alg, secret, secretlen,
108 					 false, NULL, now, now, mctx, ring,
109 					 &tsigkey);
110 		isc_mem_put(mctx, secret, secretalloc);
111 		secret = NULL;
112 		if (ret != ISC_R_SUCCESS) {
113 			goto failure;
114 		}
115 		/*
116 		 * Set digest bits.
117 		 */
118 		dst_key_setbits(tsigkey->key, bits);
119 		dns_tsigkey_detach(&tsigkey);
120 	}
121 
122 	return (ISC_R_SUCCESS);
123 
124 failure:
125 	cfg_obj_log(key, named_g_lctx, ISC_LOG_ERROR,
126 		    "configuring key '%s': %s", keyid, isc_result_totext(ret));
127 
128 	if (secret != NULL) {
129 		isc_mem_put(mctx, secret, secretalloc);
130 	}
131 	return (ret);
132 }
133 
134 isc_result_t
135 named_tsigkeyring_fromconfig(const cfg_obj_t *config, const cfg_obj_t *vconfig,
136 			     isc_mem_t *mctx, dns_tsig_keyring_t **ringp) {
137 	const cfg_obj_t *maps[3];
138 	const cfg_obj_t *keylist;
139 	dns_tsig_keyring_t *ring = NULL;
140 	isc_result_t result;
141 	int i;
142 
143 	REQUIRE(ringp != NULL && *ringp == NULL);
144 
145 	i = 0;
146 	if (config != NULL) {
147 		maps[i++] = config;
148 	}
149 	if (vconfig != NULL) {
150 		maps[i++] = cfg_tuple_get(vconfig, "options");
151 	}
152 	maps[i] = NULL;
153 
154 	result = dns_tsigkeyring_create(mctx, &ring);
155 	if (result != ISC_R_SUCCESS) {
156 		return (result);
157 	}
158 
159 	for (i = 0;; i++) {
160 		if (maps[i] == NULL) {
161 			break;
162 		}
163 		keylist = NULL;
164 		result = cfg_map_get(maps[i], "key", &keylist);
165 		if (result != ISC_R_SUCCESS) {
166 			continue;
167 		}
168 		result = add_initial_keys(keylist, ring, mctx);
169 		if (result != ISC_R_SUCCESS) {
170 			goto failure;
171 		}
172 	}
173 
174 	*ringp = ring;
175 	return (ISC_R_SUCCESS);
176 
177 failure:
178 	dns_tsigkeyring_detach(&ring);
179 	return (result);
180 }
181