/* demos/sign/sign.c *//* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) * All rights reserved. * * This package is an SSL implementation written * by Eric Young (eay@cryptsoft.com). * The implementation was written so as to conform with Netscapes SSL. *  * This library is free for commercial and non-commercial use as long as * the following conditions are aheared to.  The following conditions * apply to all code found in this distribution, be it the RC4, RSA, * lhash, DES, etc., code; not just the SSL code.  The SSL documentation * included with this distribution is covered by the same copyright terms * except that the holder is Tim Hudson (tjh@cryptsoft.com). *  * Copyright remains Eric Young's, and as such any Copyright notices in * the code are not to be removed. * If this package is used in a product, Eric Young should be given attribution * as the author of the parts of the library used. * This can be in the form of a textual message at program startup or * in documentation (online or textual) provided with the package. *  * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the copyright *    notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright *    notice, this list of conditions and the following disclaimer in the *    documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software *    must display the following acknowledgement: *    "This product includes cryptographic software written by *     Eric Young (eay@cryptsoft.com)" *    The word 'cryptographic' can be left out if the rouines from the library *    being used are not cryptographic related :-). * 4. If you include any Windows specific code (or a derivative thereof) from  *    the apps directory (application code) you must include an acknowledgement: *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" *  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. *  * The licence and distribution terms for any publically available version or * derivative of this code cannot be changed.  i.e. this code cannot simply be * copied and put under another distribution licence * [including the GNU Public Licence.] *//* sign-it.cpp  -  Simple test app using SSLeay envelopes to sign data   29.9.1996, Sampo Kellomaki <sampo@iki.fi> *//* converted to C - eay :-) *//* reformated a bit and converted to use the more common functions: this was * initially written at the dawn of time :-) - Steve. */#include <stdio.h>#include <openssl/rsa.h>#include <openssl/evp.h>#include <openssl/objects.h>#include <openssl/x509.h>#include <openssl/err.h>#include <openssl/pem.h>#include <openssl/ssl.h>int main (){  int err;  int sig_len;  unsigned char sig_buf [4096];  static char certfile[] = "cert.pem";  static char keyfile[]  = "key.pem";  static char data[]     = "I owe you...";  EVP_MD_CTX     md_ctx;  EVP_PKEY *      pkey;  FILE *          fp;  X509 *	x509;  /* Just load the crypto library error strings,   * SSL_load_error_strings() loads the crypto AND the SSL ones */  /* SSL_load_error_strings();*/  ERR_load_crypto_strings();    /* Read private key */    fp = fopen (keyfile, "r");  if (fp == NULL) exit (1);  pkey = PEM_read_PrivateKey(fp, NULL, NULL, NULL);  fclose (fp);  if (pkey == NULL) { 	ERR_print_errors_fp (stderr);	exit (1);  }    /* Do the signature */    EVP_SignInit   (&md_ctx, EVP_sha1());  EVP_SignUpdate (&md_ctx, data, strlen(data));  sig_len = sizeof(sig_buf);  err = EVP_SignFinal (&md_ctx, sig_buf, &sig_len, pkey);  if (err != 1) {	ERR_print_errors_fp(stderr);	exit (1);  }  EVP_PKEY_free (pkey);    /* Read public key */    fp = fopen (certfile, "r");  if (fp == NULL) exit (1);  x509 = PEM_read_X509(fp, NULL, NULL, NULL);  fclose (fp);  if (x509 == NULL) {	ERR_print_errors_fp (stderr);	exit (1);  }    /* Get public key - eay */  pkey=X509_get_pubkey(x509);  if (pkey == NULL) {	ERR_print_errors_fp (stderr);	exit (1);  }  /* Verify the signature */    EVP_VerifyInit   (&md_ctx, EVP_sha1());  EVP_VerifyUpdate (&md_ctx, data, strlen((char*)data));  err = EVP_VerifyFinal (&md_ctx, sig_buf, sig_len, pkey);  EVP_PKEY_free (pkey);  if (err != 1) {	ERR_print_errors_fp (stderr);	exit (1);  }  printf ("Signature Verified Ok.\n");  return(0);}