demos/sign/sign.c

   1 /* demos/sign/sign.c */
   2 /* Copyright (C) 1995-1997 Eric Young (eay@cryptsoft.com)
   3  * All rights reserved.
   4  *
   5  * This package is an SSL implementation written
   6  * by Eric Young (eay@cryptsoft.com).
   7  * The implementation was written so as to conform with Netscapes SSL.
   8  *
   9  * This library is free for commercial and non-commercial use as long as
  10  * the following conditions are aheared to.  The following conditions
  11  * apply to all code found in this distribution, be it the RC4, RSA,
  12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  13  * included with this distribution is covered by the same copyright terms
  14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  15  *
  16  * Copyright remains Eric Young's, and as such any Copyright notices in
  17  * the code are not to be removed.
  18  * If this package is used in a product, Eric Young should be given attribution
  19  * as the author of the parts of the library used.
  20  * This can be in the form of a textual message at program startup or
  21  * in documentation (online or textual) provided with the package.
  22  *
  23  * Redistribution and use in source and binary forms, with or without
  24  * modification, are permitted provided that the following conditions
  25  * are met:
  26  * 1. Redistributions of source code must retain the copyright
  27  *    notice, this list of conditions and the following disclaimer.
  28  * 2. Redistributions in binary form must reproduce the above copyright
  29  *    notice, this list of conditions and the following disclaimer in the
  30  *    documentation and/or other materials provided with the distribution.
  31  * 3. All advertising materials mentioning features or use of this software
  32  *    must display the following acknowledgement:
  33  *    "This product includes cryptographic software written by
  34  *     Eric Young (eay@cryptsoft.com)"
  35  *    The word 'cryptographic' can be left out if the rouines from the library
  36  *    being used are not cryptographic related :-).
  37  * 4. If you include any Windows specific code (or a derivative thereof) from
  38  *    the apps directory (application code) you must include an acknowledgement:
  39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  40  *
  41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  51  * SUCH DAMAGE.
  52  *
  53  * The licence and distribution terms for any publically available version or
  54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
  55  * copied and put under another distribution licence
  56  * [including the GNU Public Licence.]
  57  */
  58
  59 /* sign-it.cpp  -  Simple test app using SSLeay envelopes to sign data
  60    29.9.1996, Sampo Kellomaki <sampo@iki.fi> */
  61
  62 /* converted to C - eay :-) */
  63
  64 #include <stdio.h>
  65 #include "rsa.h"
  66 #include "evp.h"
  67 #include "objects.h"
  68 #include "x509.h"
  69 #include "err.h"
  70 #include "pem.h"
  71 #include "ssl.h"
  72
  73 void main ()
  74 {
  75   int err;
  76   int sig_len;
  77   unsigned char sig_buf [4096];
  78   static char certfile[] = "cert.pem";
  79   static char keyfile[]  = "key.pem";
  80   static char data[]     = "I owe you...";
  81   EVP_MD_CTX     md_ctx;
  82   EVP_PKEY *      pkey;
  83   FILE *          fp;
  84   X509 *        x509;
  85
  86   /* Just load the crypto library error strings,
  87    * SSL_load_error_strings() loads the crypto AND the SSL ones */
  88   /* SSL_load_error_strings();*/
  89   ERR_load_crypto_strings();
  90
  91   /* Read private key */
  92
  93   fp = fopen (keyfile, "r");   if (fp == NULL) exit (1);
  94   pkey = (EVP_PKEY*)PEM_ASN1_read ((char *(*)())d2i_PrivateKey,
  95                                    PEM_STRING_EVP_PKEY,
  96                                    fp,
  97                                    NULL, NULL);
  98   if (pkey == NULL) {  ERR_print_errors_fp (stderr);    exit (1);  }
  99   fclose (fp);
 100
 101   /* Do the signature */
 102
 103   EVP_SignInit   (&md_ctx, EVP_md5());
 104   EVP_SignUpdate (&md_ctx, data, strlen(data));
 105   sig_len = sizeof(sig_buf);
 106   err = EVP_SignFinal (&md_ctx,
 107                        sig_buf,
 108                        &sig_len,
 109                        pkey);
 110   if (err != 1) {  ERR_print_errors_fp (stderr);    exit (1);  }
 111   EVP_PKEY_free (pkey);
 112
 113   /* Read public key */
 114
 115   fp = fopen (certfile, "r");   if (fp == NULL) exit (1);
 116   x509 = (X509 *)PEM_ASN1_read ((char *(*)())d2i_X509,
 117                                    PEM_STRING_X509,
 118                                    fp, NULL, NULL);
 119   if (x509 == NULL) {  ERR_print_errors_fp (stderr);    exit (1);  }
 120   fclose (fp);
 121
 122   /* Get public key - eay */
 123   pkey=X509_extract_key(x509);
 124   if (pkey == NULL) {  ERR_print_errors_fp (stderr);    exit (1);  }
 125
 126   /* Verify the signature */
 127
 128   EVP_VerifyInit   (&md_ctx, EVP_md5());
 129   EVP_VerifyUpdate (&md_ctx, data, strlen((char*)data));
 130   err = EVP_VerifyFinal (&md_ctx,
 131                          sig_buf,
 132                          sig_len,
 133                          pkey);
 134   if (err != 1) {  ERR_print_errors_fp (stderr);    exit (1);  }
 135   EVP_PKEY_free (pkey);
 136   printf ("Signature Verified Ok.\n");
 137 }