aboutsummaryrefslogtreecommitdiff
path: root/tools/cert_create/src/cert.c
blob: 8e8aee699c945d8854945b60a842c73af7213281 (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
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
/*
 * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <openssl/conf.h>
#include <openssl/err.h>
#include <openssl/opensslv.h>
#include <openssl/pem.h>
#include <openssl/sha.h>
#include <openssl/x509v3.h>

#if USE_TBBR_DEFS
#include <tbbr_oid.h>
#else
#include <platform_oid.h>
#endif

#include "cert.h"
#include "cmd_opt.h"
#include "debug.h"
#include "key.h"
#include "sha.h"

#define SERIAL_RAND_BITS	64
#define RSA_SALT_LEN		32

int rand_serial(BIGNUM *b, ASN1_INTEGER *ai)
{
	BIGNUM *btmp;
	int ret = 0;
	if (b)
		btmp = b;
	else
		btmp = BN_new();

	if (!btmp)
		return 0;

	if (!BN_pseudo_rand(btmp, SERIAL_RAND_BITS, 0, 0))
		goto error;
	if (ai && !BN_to_ASN1_INTEGER(btmp, ai))
		goto error;

	ret = 1;

error:

	if (!b)
		BN_free(btmp);

	return ret;
}
const EVP_MD *get_digest(int alg)
{
	switch (alg) {
	case HASH_ALG_SHA256:
		return EVP_sha256();
	case HASH_ALG_SHA384:
		return EVP_sha384();
	case HASH_ALG_SHA512:
		return EVP_sha512();
	default:
		return NULL;
	}
}

int cert_add_ext(X509 *issuer, X509 *subject, int nid, char *value)
{
	X509_EXTENSION *ex;
	X509V3_CTX ctx;

	/* No configuration database */
	X509V3_set_ctx_nodb(&ctx);

	/* Set issuer and subject certificates in the context */
	X509V3_set_ctx(&ctx, issuer, subject, NULL, NULL, 0);
	ex = X509V3_EXT_conf_nid(NULL, &ctx, nid, value);
	if (!ex) {
		ERR_print_errors_fp(stdout);
		return 0;
	}

	X509_add_ext(subject, ex, -1);
	X509_EXTENSION_free(ex);

	return 1;
}

int cert_new(
	int key_alg,
	int md_alg,
	cert_t *cert,
	int days,
	int ca,
	STACK_OF(X509_EXTENSION) * sk)
{
	EVP_PKEY *pkey = keys[cert->key].key;
	cert_t *issuer_cert = &certs[cert->issuer];
	EVP_PKEY *ikey = keys[issuer_cert->key].key;
	X509 *issuer = issuer_cert->x;
	X509 *x;
	X509_EXTENSION *ex;
	X509_NAME *name;
	ASN1_INTEGER *sno;
	int i, num, rc = 0;
	EVP_MD_CTX *mdCtx;
	EVP_PKEY_CTX *pKeyCtx = NULL;

	/* Create the certificate structure */
	x = X509_new();
	if (!x) {
		return 0;
	}

	/* If we do not have a key, use the issuer key (the certificate will
	 * become self signed). This happens in content certificates. */
	if (!pkey) {
		pkey = ikey;
	}

	/* If we do not have an issuer certificate, use our own (the certificate
	 * will become self signed) */
	if (!issuer) {
		issuer = x;
	}

	mdCtx = EVP_MD_CTX_create();
	if (mdCtx == NULL) {
		ERR_print_errors_fp(stdout);
		goto END;
	}

	/* Sign the certificate with the issuer key */
	if (!EVP_DigestSignInit(mdCtx, &pKeyCtx, get_digest(md_alg), NULL, ikey)) {
		ERR_print_errors_fp(stdout);
		goto END;
	}

	/*
	 * Set additional parameters if algorithm is RSA PSS. This is not
	 * required for RSA 1.5 or ECDSA.
	 */
	if (key_alg == KEY_ALG_RSA) {
		if (!EVP_PKEY_CTX_set_rsa_padding(pKeyCtx, RSA_PKCS1_PSS_PADDING)) {
			ERR_print_errors_fp(stdout);
			goto END;
		}

		if (!EVP_PKEY_CTX_set_rsa_pss_saltlen(pKeyCtx, RSA_SALT_LEN)) {
			ERR_print_errors_fp(stdout);
			goto END;
		}

		if (!EVP_PKEY_CTX_set_rsa_mgf1_md(pKeyCtx, get_digest(md_alg))) {
			ERR_print_errors_fp(stdout);
			goto END;
		}
	}

	/* x509.v3 */
	X509_set_version(x, 2);

	/* Random serial number */
	sno = ASN1_INTEGER_new();
	rand_serial(NULL, sno);
	X509_set_serialNumber(x, sno);
	ASN1_INTEGER_free(sno);

	X509_gmtime_adj(X509_get_notBefore(x), 0);
	X509_gmtime_adj(X509_get_notAfter(x), (long)60*60*24*days);
	X509_set_pubkey(x, pkey);

	/* Subject name */
	name = X509_get_subject_name(x);
	X509_NAME_add_entry_by_txt(name, "CN", MBSTRING_ASC,
			(const unsigned char *)cert->cn, -1, -1, 0);
	X509_set_subject_name(x, name);

	/* Issuer name */
	name = X509_get_issuer_name(x);
	X509_NAME_add_entry_by_txt(name, "CN", MBSTRING_ASC,
			(const unsigned char *)issuer_cert->cn, -1, -1, 0);
	X509_set_issuer_name(x, name);

	/* Add various extensions: standard extensions */
	cert_add_ext(issuer, x, NID_subject_key_identifier, "hash");
	cert_add_ext(issuer, x, NID_authority_key_identifier, "keyid:always");
	if (ca) {
		cert_add_ext(issuer, x, NID_basic_constraints, "CA:TRUE");
		cert_add_ext(issuer, x, NID_key_usage, "keyCertSign");
	} else {
		cert_add_ext(issuer, x, NID_basic_constraints, "CA:FALSE");
	}

	/* Add custom extensions */
	if (sk != NULL) {
		num = sk_X509_EXTENSION_num(sk);
		for (i = 0; i < num; i++) {
			ex = sk_X509_EXTENSION_value(sk, i);
			X509_add_ext(x, ex, -1);
		}
	}

	if (!X509_sign_ctx(x, mdCtx)) {
		ERR_print_errors_fp(stdout);
		goto END;
	}

	/* X509 certificate signed successfully */
	rc = 1;
	cert->x = x;

END:
	EVP_MD_CTX_destroy(mdCtx);
	return rc;
}

int cert_init(void)
{
	cmd_opt_t cmd_opt;
	cert_t *cert;
	unsigned int i;

	for (i = 0; i < num_certs; i++) {
		cert = &certs[i];
		cmd_opt.long_opt.name = cert->opt;
		cmd_opt.long_opt.has_arg = required_argument;
		cmd_opt.long_opt.flag = NULL;
		cmd_opt.long_opt.val = CMD_OPT_CERT;
		cmd_opt.help_msg = cert->help_msg;
		cmd_opt_add(&cmd_opt);
	}

	return 0;
}

cert_t *cert_get_by_opt(const char *opt)
{
	cert_t *cert;
	unsigned int i;

	for (i = 0; i < num_certs; i++) {
		cert = &certs[i];
		if (0 == strcmp(cert->opt, opt)) {
			return cert;
		}
	}

	return NULL;
}