/* $OpenBSD: verify.c,v 1.6 2015/10/17 15:00:11 doug Exp $ */
/* 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 "apps.h"

#include <openssl/bio.h>
#include <openssl/err.h>
#include <openssl/pem.h>
#include <openssl/x509.h>
#include <openssl/x509v3.h>

static int cb(int ok, X509_STORE_CTX * ctx);
static int check(X509_STORE * ctx, char *file, STACK_OF(X509) * uchain,
    STACK_OF(X509) * tchain, STACK_OF(X509_CRL) * crls);
static int v_verbose = 0, vflags = 0;

int
verify_main(int argc, char **argv)
{
	int i, ret = 1, badarg = 0;
	char *CApath = NULL, *CAfile = NULL;
	char *untfile = NULL, *trustfile = NULL, *crlfile = NULL;
	STACK_OF(X509) * untrusted = NULL, *trusted = NULL;
	STACK_OF(X509_CRL) * crls = NULL;
	X509_STORE *cert_ctx = NULL;
	X509_LOOKUP *lookup = NULL;
	X509_VERIFY_PARAM *vpm = NULL;

	if (single_execution) {
		if (pledge("stdio rpath", NULL) == -1) {
			perror("pledge");
			exit(1);
		}
	}

	cert_ctx = X509_STORE_new();
	if (cert_ctx == NULL)
		goto end;
	X509_STORE_set_verify_cb(cert_ctx, cb);

	argc--;
	argv++;
	for (;;) {
		if (argc >= 1) {
			if (strcmp(*argv, "-CApath") == 0) {
				if (argc-- < 1)
					goto end;
				CApath = *(++argv);
			} else if (strcmp(*argv, "-CAfile") == 0) {
				if (argc-- < 1)
					goto end;
				CAfile = *(++argv);
			} else if (args_verify(&argv, &argc, &badarg, bio_err,
			    &vpm)) {
				if (badarg)
					goto end;
				continue;
			} else if (strcmp(*argv, "-untrusted") == 0) {
				if (argc-- < 1)
					goto end;
				untfile = *(++argv);
			} else if (strcmp(*argv, "-trusted") == 0) {
				if (argc-- < 1)
					goto end;
				trustfile = *(++argv);
			} else if (strcmp(*argv, "-CRLfile") == 0) {
				if (argc-- < 1)
					goto end;
				crlfile = *(++argv);
			}
			else if (strcmp(*argv, "-help") == 0)
				goto end;
			else if (strcmp(*argv, "-verbose") == 0)
				v_verbose = 1;
			else if (argv[0][0] == '-')
				goto end;
			else
				break;
			argc--;
			argv++;
		} else
			break;
	}

	if (vpm)
		X509_STORE_set1_param(cert_ctx, vpm);

	lookup = X509_STORE_add_lookup(cert_ctx, X509_LOOKUP_file());
	if (lookup == NULL)
		abort();
	if (CAfile) {
		i = X509_LOOKUP_load_file(lookup, CAfile, X509_FILETYPE_PEM);
		if (!i) {
			BIO_printf(bio_err, "Error loading file %s\n", CAfile);
			ERR_print_errors(bio_err);
			goto end;
		}
	} else
		X509_LOOKUP_load_file(lookup, NULL, X509_FILETYPE_DEFAULT);

	lookup = X509_STORE_add_lookup(cert_ctx, X509_LOOKUP_hash_dir());
	if (lookup == NULL)
		abort();
	if (CApath) {
		i = X509_LOOKUP_add_dir(lookup, CApath, X509_FILETYPE_PEM);
		if (!i) {
			BIO_printf(bio_err, "Error loading directory %s\n", CApath);
			ERR_print_errors(bio_err);
			goto end;
		}
	} else
		X509_LOOKUP_add_dir(lookup, NULL, X509_FILETYPE_DEFAULT);

	ERR_clear_error();

	if (untfile) {
		untrusted = load_certs(bio_err, untfile, FORMAT_PEM,
		    NULL, "untrusted certificates");
		if (!untrusted)
			goto end;
	}
	if (trustfile) {
		trusted = load_certs(bio_err, trustfile, FORMAT_PEM,
		    NULL, "trusted certificates");
		if (!trusted)
			goto end;
	}
	if (crlfile) {
		crls = load_crls(bio_err, crlfile, FORMAT_PEM,
		    NULL, "other CRLs");
		if (!crls)
			goto end;
	}
	ret = 0;
	if (argc < 1) {
		if (1 != check(cert_ctx, NULL, untrusted, trusted, crls))
			ret = -1;
	} else {
		for (i = 0; i < argc; i++)
			if (1 != check(cert_ctx, argv[i], untrusted, trusted,
			    crls))
				ret = -1;
	}

end:
	if (ret == 1) {
		BIO_printf(bio_err, "usage: verify [-verbose] [-CApath path] [-CAfile file] [-purpose purpose] [-crl_check]");
		BIO_printf(bio_err, " [-attime timestamp]");
		BIO_printf(bio_err, " cert1 cert2 ...\n");

		BIO_printf(bio_err, "recognized usages:\n");
		for (i = 0; i < X509_PURPOSE_get_count(); i++) {
			X509_PURPOSE *ptmp;
			ptmp = X509_PURPOSE_get0(i);
			BIO_printf(bio_err, "\t%-10s\t%s\n",
			    X509_PURPOSE_get0_sname(ptmp),
			    X509_PURPOSE_get0_name(ptmp));
		}
	}
	if (vpm)
		X509_VERIFY_PARAM_free(vpm);
	if (cert_ctx != NULL)
		X509_STORE_free(cert_ctx);
	sk_X509_pop_free(untrusted, X509_free);
	sk_X509_pop_free(trusted, X509_free);
	sk_X509_CRL_pop_free(crls, X509_CRL_free);

	return (ret < 0 ? 2 : ret);
}

static int
check(X509_STORE * ctx, char *file, STACK_OF(X509) * uchain,
    STACK_OF(X509) * tchain, STACK_OF(X509_CRL) * crls)
{
	X509 *x = NULL;
	int i = 0, ret = 0;
	X509_STORE_CTX *csc;

	x = load_cert(bio_err, file, FORMAT_PEM, NULL, "certificate file");
	if (x == NULL)
		goto end;
	fprintf(stdout, "%s: ", (file == NULL) ? "stdin" : file);

	csc = X509_STORE_CTX_new();
	if (csc == NULL) {
		ERR_print_errors(bio_err);
		goto end;
	}
	X509_STORE_set_flags(ctx, vflags);
	if (!X509_STORE_CTX_init(csc, ctx, x, uchain)) {
		ERR_print_errors(bio_err);
		goto end;
	}
	if (tchain)
		X509_STORE_CTX_trusted_stack(csc, tchain);
	if (crls)
		X509_STORE_CTX_set0_crls(csc, crls);
	i = X509_verify_cert(csc);
	X509_STORE_CTX_free(csc);

	ret = 0;

end:
	if (i > 0) {
		fprintf(stdout, "OK\n");
		ret = 1;
	} else
		ERR_print_errors(bio_err);
	if (x != NULL)
		X509_free(x);

	return (ret);
}

static int
cb(int ok, X509_STORE_CTX * ctx)
{
	int cert_error = X509_STORE_CTX_get_error(ctx);
	X509 *current_cert = X509_STORE_CTX_get_current_cert(ctx);

	if (!ok) {
		if (current_cert) {
			X509_NAME_print_ex_fp(stdout,
			    X509_get_subject_name(current_cert),
			    0, XN_FLAG_ONELINE);
			printf("\n");
		}
		printf("%serror %d at %d depth lookup:%s\n",
		    X509_STORE_CTX_get0_parent_ctx(ctx) ? "[CRL path]" : "",
		    cert_error,
		    X509_STORE_CTX_get_error_depth(ctx),
		    X509_verify_cert_error_string(cert_error));
		switch (cert_error) {
		case X509_V_ERR_NO_EXPLICIT_POLICY:
			policies_print(NULL, ctx);
		case X509_V_ERR_CERT_HAS_EXPIRED:

			/*
			 * since we are just checking the certificates, it is
			 * ok if they are self signed. But we should still
			 * warn the user.
			 */

		case X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT:
			/* Continue after extension errors too */
		case X509_V_ERR_INVALID_CA:
		case X509_V_ERR_INVALID_NON_CA:
		case X509_V_ERR_PATH_LENGTH_EXCEEDED:
		case X509_V_ERR_INVALID_PURPOSE:
		case X509_V_ERR_CRL_HAS_EXPIRED:
		case X509_V_ERR_CRL_NOT_YET_VALID:
		case X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION:
			ok = 1;

		}

		return ok;

	}
	if (cert_error == X509_V_OK && ok == 2)
		policies_print(NULL, ctx);
	if (!v_verbose)
		ERR_clear_error();
	return (ok);
}