Merge branch 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm
[sfrench/cifs-2.6.git] / scripts / extract-cert.c
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))
29 void format(void)
30 {
31         fprintf(stderr,
32                 "Usage: scripts/extract-cert <source> <dest>\n");
33         exit(2);
34 }
35
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
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
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
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 }