/* crypto/pkcs7/verify.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.]

 */

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <openssl/bio.h>

#include <openssl/x509.h>

#include <openssl/pem.h>

#include <openssl/err.h>

#include <openssl/asn1.h>

int verify_callback(int ok, X509_STORE_CTX *ctx);

BIO *bio_err=NULL;

int main(argc,argv)

int argc;

char *argv[];

	{

	char *keyfile=NULL;

	BIO *in;

	EVP_PKEY *pkey;

	X509 *x509;

	PKCS7 *p7;

	PKCS7_SIGNER_INFO *si;

	X509_STORE_CTX cert_ctx;

	X509_STORE *cert_store=NULL;

	BIO *data,*detached=NULL,*p7bio=NULL;

	char buf[1024*4];

	unsigned char *pp;

	int i,printit=0;

	STACK_OF(PKCS7_SIGNER_INFO) *sk;

	OpenSSL_add_all_algorithms();

	bio_err=BIO_new_fp(stderr,BIO_NOCLOSE);

	data=BIO_new(BIO_s_file());

	pp=NULL;

	while (argc > 1)

		{

		argc--;

		argv++;

		if (strcmp(argv[0],"-p") == 0)

			{

			printit=1;

			}

		else if ((strcmp(argv[0],"-k") == 0) && (argc >= 2)) {

			keyfile = argv[1];

			argc-=1;

			argv+=1;

		} else if ((strcmp(argv[0],"-d") == 0) && (argc >= 2))

			{

			detached=BIO_new(BIO_s_file());

			if (!BIO_read_filename(detached,argv[1]))

				goto err;

			argc-=1;

			argv+=1;

			}

		else break;

		}

	 if (!BIO_read_filename(data,argv[0])) goto err; 

	if(!keyfile) {

		fprintf(stderr, "No private key file specified\n");

		goto err;

	}

        if ((in=BIO_new_file(keyfile,"r")) == NULL) goto err;

        if ((x509=PEM_read_bio_X509(in,NULL,NULL,NULL)) == NULL) goto err;

        BIO_reset(in);

        if ((pkey=PEM_read_bio_PrivateKey(in,NULL,NULL,NULL)) == NULL)

		goto err;

        BIO_free(in);

	if (pp == NULL)

		BIO_set_fp(data,stdin,BIO_NOCLOSE);

	/* Load the PKCS7 object from a file */

	if ((p7=PEM_read_bio_PKCS7(data,NULL,NULL,NULL)) == NULL) goto err;

	/* This stuff is being setup for certificate verification.

	 * When using SSL, it could be replaced with a 

	 * cert_stre=SSL_CTX_get_cert_store(ssl_ctx); */

	cert_store=X509_STORE_new();

	X509_STORE_set_default_paths(cert_store);

	X509_STORE_load_locations(cert_store,NULL,"../../certs");

	X509_STORE_set_verify_cb_func(cert_store,verify_callback);

	ERR_clear_error();

	/* We need to process the data */

	/* We cannot support detached encryption */

	p7bio=PKCS7_dataDecode(p7,pkey,detached,x509);

	if (p7bio == NULL)

		{

		printf("problems decoding\n");

		goto err;

		}

	/* We now have to 'read' from p7bio to calculate digests etc. */

	for (;;)

		{

		i=BIO_read(p7bio,buf,sizeof(buf));

		/* print it? */

		if (i <= 0) break;

		fwrite(buf,1, i, stdout);

		}

	/* We can now verify signatures */

	sk=PKCS7_get_signer_info(p7);

	if (sk == NULL)

		{

		fprintf(stderr, "there are no signatures on this data\n");

		}

	else

		{

		/* Ok, first we need to, for each subject entry,

		 * see if we can verify */

		ERR_clear_error();

		for (i=0; i<sk_PKCS7_SIGNER_INFO_num(sk); i++)

			{

			si=sk_PKCS7_SIGNER_INFO_value(sk,i);

			i=PKCS7_dataVerify(cert_store,&cert_ctx,p7bio,p7,si);

			if (i <= 0)

				goto err;

			else

				fprintf(stderr,"Signature verified\n");

			}

		}

	X509_STORE_free(cert_store);

	exit(0);

err:

	ERR_load_crypto_strings();

	ERR_print_errors_fp(stderr);

	exit(1);

	}

/* should be X509 * but we can just have them as char *. */

int verify_callback(int ok, X509_STORE_CTX *ctx)

	{

	char buf[256];

	X509 *err_cert;

	int err,depth;

	err_cert=X509_STORE_CTX_get_current_cert(ctx);

	err=	X509_STORE_CTX_get_error(ctx);

	depth=	X509_STORE_CTX_get_error_depth(ctx);

	X509_NAME_oneline(X509_get_subject_name(err_cert),buf,256);

	BIO_printf(bio_err,"depth=%d %s\n",depth,buf);

	if (!ok)

		{

		BIO_printf(bio_err,"verify error:num=%d:%s\n",err,

			X509_verify_cert_error_string(err));

		if (depth < 6)

			{

			ok=1;

			X509_STORE_CTX_set_error(ctx,X509_V_OK);

			}

		else

			{

			ok=0;

			X509_STORE_CTX_set_error(ctx,X509_V_ERR_CERT_CHAIN_TOO_LONG);

			}

		}

	switch (ctx->error)

		{

	case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT:

		X509_NAME_oneline(X509_get_issuer_name(ctx->current_cert),buf,256);

		BIO_printf(bio_err,"issuer= %s\n",buf);

		break;

	case X509_V_ERR_CERT_NOT_YET_VALID:

	case X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD:

		BIO_printf(bio_err,"notBefore=");

		ASN1_UTCTIME_print(bio_err,X509_get_notBefore(ctx->current_cert));

		BIO_printf(bio_err,"\n");

		break;

	case X509_V_ERR_CERT_HAS_EXPIRED:

	case X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD:

		BIO_printf(bio_err,"notAfter=");

		ASN1_UTCTIME_print(bio_err,X509_get_notAfter(ctx->current_cert));

		BIO_printf(bio_err,"\n");

		break;

		}

	BIO_printf(bio_err,"verify return:%d\n",ok);

	return(ok);

	}