certs/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 #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
  38 static __attribute__((noreturn))
  39 void format(void)
  40 {
  41         fprintf(stderr,
  42                 "Usage: extract-cert <source> <dest>\n");
  43         exit(2);
  44 }
  45
  46 static const char *key_pass;
  47 static BIO *wb;
  48 static char *cert_dst;
  49 static bool verbose;
  50
  51 static 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
  65 static 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
 125 int 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 }