summaryrefslogtreecommitdiffstats
path: root/bin/confgen/keygen.c
blob: 73f976c639627580c870f7bcdba1b9dc4c518b9b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
/*
 * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
 *
 * SPDX-License-Identifier: MPL-2.0
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, you can obtain one at https://mozilla.org/MPL/2.0/.
 *
 * See the COPYRIGHT file distributed with this work for additional
 * information regarding copyright ownership.
 */

/*! \file */

#include "keygen.h"
#include <stdarg.h>
#include <stdlib.h>

#include <isc/base64.h>
#include <isc/buffer.h>
#include <isc/file.h>
#include <isc/mem.h>
#include <isc/print.h>
#include <isc/result.h>
#include <isc/string.h>

#include <pk11/site.h>

#include <dns/keyvalues.h>
#include <dns/name.h>

#include <dst/dst.h>

#include <confgen/os.h>

#include "util.h"

/*%
 * Convert algorithm type to string.
 */
const char *
alg_totext(dns_secalg_t alg) {
	switch (alg) {
	case DST_ALG_HMACMD5:
		return ("hmac-md5");
	case DST_ALG_HMACSHA1:
		return ("hmac-sha1");
	case DST_ALG_HMACSHA224:
		return ("hmac-sha224");
	case DST_ALG_HMACSHA256:
		return ("hmac-sha256");
	case DST_ALG_HMACSHA384:
		return ("hmac-sha384");
	case DST_ALG_HMACSHA512:
		return ("hmac-sha512");
	default:
		return ("(unknown)");
	}
}

/*%
 * Convert string to algorithm type.
 */
dns_secalg_t
alg_fromtext(const char *name) {
	const char *p = name;
	if (strncasecmp(p, "hmac-", 5) == 0) {
		p = &name[5];
	}

	if (strcasecmp(p, "md5") == 0) {
		return (DST_ALG_HMACMD5);
	}
	if (strcasecmp(p, "sha1") == 0) {
		return (DST_ALG_HMACSHA1);
	}
	if (strcasecmp(p, "sha224") == 0) {
		return (DST_ALG_HMACSHA224);
	}
	if (strcasecmp(p, "sha256") == 0) {
		return (DST_ALG_HMACSHA256);
	}
	if (strcasecmp(p, "sha384") == 0) {
		return (DST_ALG_HMACSHA384);
	}
	if (strcasecmp(p, "sha512") == 0) {
		return (DST_ALG_HMACSHA512);
	}
	return (DST_ALG_UNKNOWN);
}

/*%
 * Return default keysize for a given algorithm type.
 */
int
alg_bits(dns_secalg_t alg) {
	switch (alg) {
	case DST_ALG_HMACMD5:
		return (128);
	case DST_ALG_HMACSHA1:
		return (160);
	case DST_ALG_HMACSHA224:
		return (224);
	case DST_ALG_HMACSHA256:
		return (256);
	case DST_ALG_HMACSHA384:
		return (384);
	case DST_ALG_HMACSHA512:
		return (512);
	default:
		return (0);
	}
}

/*%
 * Generate a key of size 'keysize' and place it in 'key_txtbuffer'
 */
void
generate_key(isc_mem_t *mctx, dns_secalg_t alg, int keysize,
	     isc_buffer_t *key_txtbuffer) {
	isc_result_t result = ISC_R_SUCCESS;
	isc_buffer_t key_rawbuffer;
	isc_region_t key_rawregion;
	char key_rawsecret[64];
	dst_key_t *key = NULL;

	switch (alg) {
	case DST_ALG_HMACMD5:
	case DST_ALG_HMACSHA1:
	case DST_ALG_HMACSHA224:
	case DST_ALG_HMACSHA256:
		if (keysize < 1 || keysize > 512) {
			fatal("keysize %d out of range (must be 1-512)\n",
			      keysize);
		}
		break;
	case DST_ALG_HMACSHA384:
	case DST_ALG_HMACSHA512:
		if (keysize < 1 || keysize > 1024) {
			fatal("keysize %d out of range (must be 1-1024)\n",
			      keysize);
		}
		break;
	default:
		fatal("unsupported algorithm %d\n", alg);
	}

	DO("initialize dst library", dst_lib_init(mctx, NULL));

	DO("generate key",
	   dst_key_generate(dns_rootname, alg, keysize, 0, 0, DNS_KEYPROTO_ANY,
			    dns_rdataclass_in, mctx, &key, NULL));

	isc_buffer_init(&key_rawbuffer, &key_rawsecret, sizeof(key_rawsecret));

	DO("dump key to buffer", dst_key_tobuffer(key, &key_rawbuffer));

	isc_buffer_usedregion(&key_rawbuffer, &key_rawregion);

	DO("bsse64 encode secret",
	   isc_base64_totext(&key_rawregion, -1, "", key_txtbuffer));

	if (key != NULL) {
		dst_key_free(&key);
	}

	dst_lib_destroy();
}

/*%
 * Write a key file to 'keyfile'.  If 'user' is non-NULL,
 * make that user the owner of the file.  The key will have
 * the name 'keyname' and the secret in the buffer 'secret'.
 */
void
write_key_file(const char *keyfile, const char *user, const char *keyname,
	       isc_buffer_t *secret, dns_secalg_t alg) {
	isc_result_t result;
	const char *algname = alg_totext(alg);
	FILE *fd = NULL;

	DO("create keyfile", isc_file_safecreate(keyfile, &fd));

	if (user != NULL) {
		if (set_user(fd, user) == -1) {
			fatal("unable to set file owner\n");
		}
	}

	fprintf(fd,
		"key \"%s\" {\n\talgorithm %s;\n"
		"\tsecret \"%.*s\";\n};\n",
		keyname, algname, (int)isc_buffer_usedlength(secret),
		(char *)isc_buffer_base(secret));
	fflush(fd);
	if (ferror(fd)) {
		fatal("write to %s failed\n", keyfile);
	}
	if (fclose(fd)) {
		fatal("fclose(%s) failed\n", keyfile);
	}
	fprintf(stderr, "wrote key file \"%s\"\n", keyfile);
}