1/* Extract X.509 certificate in DER form from PKCS#11 or PEM.
2 *
3 * Copyright © 2014-2015 Red Hat, Inc. All Rights Reserved.
4 * Copyright © 2015 Intel Corporation.
5 *
6 * Authors: David Howells <dhowells@redhat.com>
7 * David Woodhouse <dwmw2@infradead.org>
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public License
11 * as published by the Free Software Foundation; either version 2.1
12 * of the licence, or (at your option) any later version.
13 */
14#define _GNU_SOURCE
15#include <stdio.h>
16#include <stdlib.h>
17#include <stdint.h>
18#include <stdbool.h>
19#include <string.h>
20#include <err.h>
21#include <openssl/bio.h>
22#include <openssl/pem.h>
23#include <openssl/err.h>
24#if OPENSSL_VERSION_MAJOR >= 3
25# define USE_PKCS11_PROVIDER
26# include <openssl/provider.h>
27# include <openssl/store.h>
28#else
29# if !defined(OPENSSL_NO_ENGINE) && !defined(OPENSSL_NO_DEPRECATED_3_0)
30# define USE_PKCS11_ENGINE
31# include <openssl/engine.h>
32# endif
33#endif
34#include "ssl-common.h"
35
36#define PKEY_ID_PKCS7 2
37
38static __attribute__((noreturn))
39void format(void)
40{
41 fprintf(stderr,
42 "Usage: extract-cert <source> <dest>\n");
43 exit(2);
44}
45
46static const char *key_pass;
47static BIO *wb;
48static char *cert_dst;
49static bool verbose;
50
51static void write_cert(X509 *x509)
52{
53 char buf[200];
54
55 if (!wb) {
56 wb = BIO_new_file(cert_dst, "wb");
57 ERR(!wb, "%s", cert_dst);
58 }
59 X509_NAME_oneline(X509_get_subject_name(x509), buf, sizeof(buf));
60 ERR(!i2d_X509_bio(wb, x509), "%s", cert_dst);
61 if (verbose)
62 fprintf(stderr, "Extracted cert: %s\n", buf);
63}
64
65static X509 *load_cert_pkcs11(const char *cert_src)
66{
67 X509 *cert = NULL;
68#ifdef USE_PKCS11_PROVIDER
69 OSSL_STORE_CTX *store;
70
71 if (!OSSL_PROVIDER_try_load(NULL, "pkcs11", true))
72 ERR(1, "OSSL_PROVIDER_try_load(pkcs11)");
73 if (!OSSL_PROVIDER_try_load(NULL, "default", true))
74 ERR(1, "OSSL_PROVIDER_try_load(default)");
75
76 store = OSSL_STORE_open(cert_src, NULL, NULL, NULL, NULL);
77 ERR(!store, "OSSL_STORE_open");
78
79 while (!OSSL_STORE_eof(store)) {
80 OSSL_STORE_INFO *info = OSSL_STORE_load(store);
81
82 if (!info) {
83 drain_openssl_errors(__LINE__, 0);
84 continue;
85 }
86 if (OSSL_STORE_INFO_get_type(info) == OSSL_STORE_INFO_CERT) {
87 cert = OSSL_STORE_INFO_get1_CERT(info);
88 ERR(!cert, "OSSL_STORE_INFO_get1_CERT");
89 }
90 OSSL_STORE_INFO_free(info);
91 if (cert)
92 break;
93 }
94 OSSL_STORE_close(store);
95#elif defined(USE_PKCS11_ENGINE)
96 ENGINE *e;
97 struct {
98 const char *cert_id;
99 X509 *cert;
100 } parms;
101
102 parms.cert_id = cert_src;
103 parms.cert = NULL;
104
105 ENGINE_load_builtin_engines();
106 drain_openssl_errors(__LINE__, 1);
107 e = ENGINE_by_id("pkcs11");
108 ERR(!e, "Load PKCS#11 ENGINE");
109 if (ENGINE_init(e))
110 drain_openssl_errors(__LINE__, 1);
111 else
112 ERR(1, "ENGINE_init");
113 if (key_pass)
114 ERR(!ENGINE_ctrl_cmd_string(e, "PIN", key_pass, 0), "Set PKCS#11 PIN");
115 ENGINE_ctrl_cmd(e, "LOAD_CERT_CTRL", 0, &parms, NULL, 1);
116 ERR(!parms.cert, "Get X.509 from PKCS#11");
117 cert = parms.cert;
118#else
119 fprintf(stderr, "no pkcs11 engine/provider available\n");
120 exit(1);
121#endif
122 return cert;
123}
124
125int main(int argc, char **argv)
126{
127 char *cert_src;
128 char *verbose_env;
129
130 OpenSSL_add_all_algorithms();
131 ERR_load_crypto_strings();
132 ERR_clear_error();
133
134 verbose_env = getenv("KBUILD_VERBOSE");
135 if (verbose_env && strchr(verbose_env, '1'))
136 verbose = true;
137
138 key_pass = getenv("KBUILD_SIGN_PIN");
139
140 if (argc != 3)
141 format();
142
143 cert_src = argv[1];
144 cert_dst = argv[2];
145
146 if (!cert_src[0]) {
147 /* Invoked with no input; create empty file */
148 FILE *f = fopen(cert_dst, "wb");
149 ERR(!f, "%s", cert_dst);
150 fclose(f);
151 exit(0);
152 } else if (!strncmp(cert_src, "pkcs11:", 7)) {
153 X509 *cert = load_cert_pkcs11(cert_src);
154
155 ERR(!cert, "load_cert_pkcs11 failed");
156 write_cert(cert);
157 } else {
158 BIO *b;
159 X509 *x509;
160
161 b = BIO_new_file(cert_src, "rb");
162 ERR(!b, "%s", cert_src);
163
164 while (1) {
165 x509 = PEM_read_bio_X509(b, NULL, NULL, NULL);
166 if (wb && !x509) {
167 unsigned long err = ERR_peek_last_error();
168 if (ERR_GET_LIB(err) == ERR_LIB_PEM &&
169 ERR_GET_REASON(err) == PEM_R_NO_START_LINE) {
170 ERR_clear_error();
171 break;
172 }
173 }
174 ERR(!x509, "%s", cert_src);
175 write_cert(x509);
176 }
177 }
178
179 BIO_free(wb);
180
181 return 0;
182}
183

source code of linux/certs/extract-cert.c