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 #include <openssl/engine.h>
25
26 #define PKEY_ID_PKCS7 2
27
28 static __attribute__((noreturn))
format(void)29 void format(void)
30 {
31 fprintf(stderr,
32 "Usage: scripts/extract-cert <source> <dest>\n");
33 exit(2);
34 }
35
display_openssl_errors(int l)36 static void display_openssl_errors(int l)
37 {
38 const char *file;
39 char buf[120];
40 int e, line;
41
42 if (ERR_peek_error() == 0)
43 return;
44 fprintf(stderr, "At main.c:%d:\n", l);
45
46 while ((e = ERR_get_error_line(&file, &line))) {
47 ERR_error_string(e, buf);
48 fprintf(stderr, "- SSL %s: %s:%d\n", buf, file, line);
49 }
50 }
51
drain_openssl_errors(void)52 static void drain_openssl_errors(void)
53 {
54 const char *file;
55 int line;
56
57 if (ERR_peek_error() == 0)
58 return;
59 while (ERR_get_error_line(&file, &line)) {}
60 }
61
62 #define ERR(cond, fmt, ...) \
63 do { \
64 bool __cond = (cond); \
65 display_openssl_errors(__LINE__); \
66 if (__cond) { \
67 err(1, fmt, ## __VA_ARGS__); \
68 } \
69 } while(0)
70
71 static const char *key_pass;
72 static BIO *wb;
73 static char *cert_dst;
74 int kbuild_verbose;
75
write_cert(X509 * x509)76 static void write_cert(X509 *x509)
77 {
78 char buf[200];
79
80 if (!wb) {
81 wb = BIO_new_file(cert_dst, "wb");
82 ERR(!wb, "%s", cert_dst);
83 }
84 X509_NAME_oneline(X509_get_subject_name(x509), buf, sizeof(buf));
85 ERR(!i2d_X509_bio(wb, x509), "%s", cert_dst);
86 if (kbuild_verbose)
87 fprintf(stderr, "Extracted cert: %s\n", buf);
88 }
89
main(int argc,char ** argv)90 int main(int argc, char **argv)
91 {
92 char *cert_src;
93
94 OpenSSL_add_all_algorithms();
95 ERR_load_crypto_strings();
96 ERR_clear_error();
97
98 kbuild_verbose = atoi(getenv("KBUILD_VERBOSE")?:"0");
99
100 key_pass = getenv("KBUILD_SIGN_PIN");
101
102 if (argc != 3)
103 format();
104
105 cert_src = argv[1];
106 cert_dst = argv[2];
107
108 if (!cert_src[0]) {
109 /* Invoked with no input; create empty file */
110 FILE *f = fopen(cert_dst, "wb");
111 ERR(!f, "%s", cert_dst);
112 fclose(f);
113 exit(0);
114 } else if (!strncmp(cert_src, "pkcs11:", 7)) {
115 ENGINE *e;
116 struct {
117 const char *cert_id;
118 X509 *cert;
119 } parms;
120
121 parms.cert_id = cert_src;
122 parms.cert = NULL;
123
124 ENGINE_load_builtin_engines();
125 drain_openssl_errors();
126 e = ENGINE_by_id("pkcs11");
127 ERR(!e, "Load PKCS#11 ENGINE");
128 if (ENGINE_init(e))
129 drain_openssl_errors();
130 else
131 ERR(1, "ENGINE_init");
132 if (key_pass)
133 ERR(!ENGINE_ctrl_cmd_string(e, "PIN", key_pass, 0), "Set PKCS#11 PIN");
134 ENGINE_ctrl_cmd(e, "LOAD_CERT_CTRL", 0, &parms, NULL, 1);
135 ERR(!parms.cert, "Get X.509 from PKCS#11");
136 write_cert(parms.cert);
137 } else {
138 BIO *b;
139 X509 *x509;
140
141 b = BIO_new_file(cert_src, "rb");
142 ERR(!b, "%s", cert_src);
143
144 while (1) {
145 x509 = PEM_read_bio_X509(b, NULL, NULL, NULL);
146 if (wb && !x509) {
147 unsigned long err = ERR_peek_last_error();
148 if (ERR_GET_LIB(err) == ERR_LIB_PEM &&
149 ERR_GET_REASON(err) == PEM_R_NO_START_LINE) {
150 ERR_clear_error();
151 break;
152 }
153 }
154 ERR(!x509, "%s", cert_src);
155 write_cert(x509);
156 }
157 }
158
159 BIO_free(wb);
160
161 return 0;
162 }
163