apps/verify.c - third_party/openssl - Git at Google

 /*
  * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
  *
  * Licensed under the Apache License 2.0 (the "License").  You may not use
  * this file except in compliance with the License.  You can obtain a copy
  * in the file LICENSE in the source distribution or at
  * https://www.openssl.org/source/license.html
  */

 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include "apps.h"
 #include "progs.h"
 #include <openssl/bio.h>
 #include <openssl/err.h>
 #include <openssl/x509.h>
 #include <openssl/x509v3.h>
 #include <openssl/pem.h>

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

 typedef enum OPTION_choice {
     OPT_COMMON,
     OPT_ENGINE, OPT_CAPATH, OPT_CAFILE, OPT_CASTORE,
     OPT_NOCAPATH, OPT_NOCAFILE, OPT_NOCASTORE,
     OPT_UNTRUSTED, OPT_TRUSTED, OPT_CRLFILE, OPT_CRL_DOWNLOAD, OPT_SHOW_CHAIN,
     OPT_V_ENUM, OPT_NAMEOPT, OPT_VFYOPT,
     OPT_VERBOSE,
     OPT_PROV_ENUM
 } OPTION_CHOICE;

 const OPTIONS verify_options[] = {
     {OPT_HELP_STR, 1, '-', "Usage: %s [options] [cert...]\n"},

     OPT_SECTION("General"),
     {"help", OPT_HELP, '-', "Display this summary"},
 #ifndef OPENSSL_NO_ENGINE
     {"engine", OPT_ENGINE, 's', "Use engine, possibly a hardware device"},
 #endif
     {"verbose", OPT_VERBOSE, '-',
         "Print extra information about the operations being performed."},
     {"nameopt", OPT_NAMEOPT, 's', "Certificate subject/issuer name printing options"},

     OPT_SECTION("Certificate chain"),
     {"trusted", OPT_TRUSTED, '<', "A file of trusted certificates"},
     {"CAfile", OPT_CAFILE, '<', "A file of trusted certificates"},
     {"CApath", OPT_CAPATH, '/', "A directory of files with trusted certificates"},
     {"CAstore", OPT_CASTORE, ':', "URI to a store of trusted certificates"},
     {"no-CAfile", OPT_NOCAFILE, '-',
      "Do not load the default trusted certificates file"},
     {"no-CApath", OPT_NOCAPATH, '-',
      "Do not load trusted certificates from the default directory"},
     {"no-CAstore", OPT_NOCASTORE, '-',
      "Do not load trusted certificates from the default certificates store"},
     {"untrusted", OPT_UNTRUSTED, '<', "A file of untrusted certificates"},
     {"CRLfile", OPT_CRLFILE, '<',
         "File containing one or more CRL's (in PEM format) to load"},
     {"crl_download", OPT_CRL_DOWNLOAD, '-',
         "Try downloading CRL information for certificates via their CDP entries"},
     {"show_chain", OPT_SHOW_CHAIN, '-',
         "Display information about the certificate chain"},

     OPT_V_OPTIONS,
     {"vfyopt", OPT_VFYOPT, 's', "Verification parameter in n:v form"},

     OPT_PROV_OPTIONS,

     OPT_PARAMETERS(),
     {"cert", 0, 0, "Certificate(s) to verify (optional; stdin used otherwise)"},
     {NULL}
 };

 int verify_main(int argc, char **argv)
 {
     ENGINE *e = NULL;
     STACK_OF(X509) *untrusted = NULL, *trusted = NULL;
     STACK_OF(X509_CRL) *crls = NULL;
     STACK_OF(OPENSSL_STRING) *vfyopts = NULL;
     X509_STORE *store = NULL;
     X509_VERIFY_PARAM *vpm = NULL;
     const char *prog, *CApath = NULL, *CAfile = NULL, *CAstore = NULL;
     int noCApath = 0, noCAfile = 0, noCAstore = 0;
     int vpmtouched = 0, crl_download = 0, show_chain = 0, i = 0, ret = 1;
     OPTION_CHOICE o;

     if ((vpm = X509_VERIFY_PARAM_new()) == NULL)
         goto end;

     prog = opt_init(argc, argv, verify_options);
     while ((o = opt_next()) != OPT_EOF) {
         switch (o) {
         case OPT_EOF:
         case OPT_ERR:
  opthelp:
             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
             goto end;
         case OPT_HELP:
             opt_help(verify_options);
             BIO_printf(bio_err, "\nRecognized certificate chain purposes:\n");
             for (i = 0; i < X509_PURPOSE_get_count(); i++) {
                 X509_PURPOSE *ptmp = X509_PURPOSE_get0(i);

                 BIO_printf(bio_err, "  %-15s  %s\n",
                         X509_PURPOSE_get0_sname(ptmp),
                         X509_PURPOSE_get0_name(ptmp));
             }

             BIO_printf(bio_err, "Recognized certificate policy names:\n");
             for (i = 0; i < X509_VERIFY_PARAM_get_count(); i++) {
                 const X509_VERIFY_PARAM *vptmp = X509_VERIFY_PARAM_get0(i);

                 BIO_printf(bio_err, "  %s\n",
                         X509_VERIFY_PARAM_get0_name(vptmp));
             }
             ret = 0;
             goto end;
         case OPT_V_CASES:
             if (!opt_verify(o, vpm))
                 goto end;
             vpmtouched++;
             break;
         case OPT_CAPATH:
             CApath = opt_arg();
             break;
         case OPT_CAFILE:
             CAfile = opt_arg();
             break;
         case OPT_CASTORE:
             CAstore = opt_arg();
             break;
         case OPT_NOCAPATH:
             noCApath = 1;
             break;
         case OPT_NOCAFILE:
             noCAfile = 1;
             break;
         case OPT_NOCASTORE:
             noCAstore = 1;
             break;
         case OPT_UNTRUSTED:
             /* Zero or more times */
             if (!load_certs(opt_arg(), 0, &untrusted, NULL,
                             "untrusted certificates"))
                 goto end;
             break;
         case OPT_TRUSTED:
             /* Zero or more times */
             noCAfile = 1;
             noCApath = 1;
             noCAstore = 1;
             if (!load_certs(opt_arg(), 0, &trusted, NULL, "trusted certificates"))
                 goto end;
             break;
         case OPT_CRLFILE:
             /* Zero or more times */
             if (!load_crls(opt_arg(), &crls, NULL, "other CRLs"))
                 goto end;
             break;
         case OPT_CRL_DOWNLOAD:
             crl_download = 1;
             break;
         case OPT_ENGINE:
             if ((e = setup_engine(opt_arg(), 0)) == NULL) {
                 /* Failure message already displayed */
                 goto end;
             }
             break;
         case OPT_SHOW_CHAIN:
             show_chain = 1;
             break;
         case OPT_NAMEOPT:
             if (!set_nameopt(opt_arg()))
                 goto end;
             break;
         case OPT_VFYOPT:
             if (!vfyopts)
                 vfyopts = sk_OPENSSL_STRING_new_null();
             if (!vfyopts || !sk_OPENSSL_STRING_push(vfyopts, opt_arg()))
                 goto opthelp;
             break;
         case OPT_VERBOSE:
             v_verbose = 1;
             break;
         case OPT_PROV_CASES:
             if (!opt_provider(o))
                 goto end;
             break;
         }
     }

     /* Extra arguments are certificates to verify. */
     argc = opt_num_rest();
     argv = opt_rest();

     if (trusted != NULL
         && (CAfile != NULL || CApath != NULL || CAstore != NULL)) {
         BIO_printf(bio_err,
                    "%s: Cannot use -trusted with -CAfile, -CApath or -CAstore\n",
                    prog);
         goto end;
     }

     if ((store = setup_verify(CAfile, noCAfile, CApath, noCApath,
                               CAstore, noCAstore)) == NULL)
         goto end;
     X509_STORE_set_verify_cb(store, cb);

     if (vpmtouched)
         X509_STORE_set1_param(store, vpm);

     ERR_clear_error();

     if (crl_download)
         store_setup_crl_download(store);

     ret = 0;
     if (argc < 1) {
         if (check(store, NULL, untrusted, trusted, crls, show_chain,
                   vfyopts) != 1)
             ret = -1;
     } else {
         for (i = 0; i < argc; i++)
             if (check(store, argv[i], untrusted, trusted, crls, show_chain,
                       vfyopts) != 1)
                 ret = -1;
     }

  end:
     X509_VERIFY_PARAM_free(vpm);
     X509_STORE_free(store);
     sk_X509_pop_free(untrusted, X509_free);
     sk_X509_pop_free(trusted, X509_free);
     sk_X509_CRL_pop_free(crls, X509_CRL_free);
     sk_OPENSSL_STRING_free(vfyopts);
     release_engine(e);
     return (ret < 0 ? 2 : ret);
 }

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

     x = load_cert(file, FORMAT_UNDEF, "certificate file");
     if (x == NULL)
         goto end;

     if (opts != NULL) {
         for (i = 0; i < sk_OPENSSL_STRING_num(opts); i++) {
             char *opt = sk_OPENSSL_STRING_value(opts, i);
             if (x509_ctrl_string(x, opt) <= 0) {
                 BIO_printf(bio_err, "parameter error \"%s\"\n", opt);
                 ERR_print_errors(bio_err);
                 return 0;
             }
         }
     }

     csc = X509_STORE_CTX_new();
     if (csc == NULL) {
         BIO_printf(bio_err, "error %s: X.509 store context allocation failed\n",
                    (file == NULL) ? "stdin" : file);
         goto end;
     }

     X509_STORE_set_flags(ctx, vflags);
     if (!X509_STORE_CTX_init(csc, ctx, x, uchain)) {
         X509_STORE_CTX_free(csc);
         BIO_printf(bio_err,
                    "error %s: X.509 store context initialization failed\n",
                    (file == NULL) ? "stdin" : file);
         goto end;
     }
     if (tchain != NULL)
         X509_STORE_CTX_set0_trusted_stack(csc, tchain);
     if (crls != NULL)
         X509_STORE_CTX_set0_crls(csc, crls);
     i = X509_verify_cert(csc);
     if (i > 0 && X509_STORE_CTX_get_error(csc) == X509_V_OK) {
         BIO_printf(bio_out, "%s: OK\n", (file == NULL) ? "stdin" : file);
         ret = 1;
         if (show_chain) {
             int j;

             chain = X509_STORE_CTX_get1_chain(csc);
             num_untrusted = X509_STORE_CTX_get_num_untrusted(csc);
             BIO_printf(bio_out, "Chain:\n");
             for (j = 0; j < sk_X509_num(chain); j++) {
                 X509 *cert = sk_X509_value(chain, j);
                 BIO_printf(bio_out, "depth=%d: ", j);
                 X509_NAME_print_ex_fp(stdout,
                                       X509_get_subject_name(cert),
                                       0, get_nameopt());
                 if (j < num_untrusted)
                     BIO_printf(bio_out, " (untrusted)");
                 BIO_printf(bio_out, "\n");
             }
             sk_X509_pop_free(chain, X509_free);
         }
     } else {
         BIO_printf(bio_err,
                    "error %s: verification failed\n",
                    (file == NULL) ? "stdin" : file);
     }
     X509_STORE_CTX_free(csc);

  end:
     if (i <= 0)
         ERR_print_errors(bio_err);
     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 != NULL) {
             X509_NAME_print_ex(bio_err,
                             X509_get_subject_name(current_cert),
                             0, get_nameopt());
             BIO_printf(bio_err, "\n");
         }
         BIO_printf(bio_err, "%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));

         /*
          * Pretend that some errors are ok, so they don't stop further
          * processing of the certificate chain.  Setting ok = 1 does this.
          * After X509_verify_cert() is done, we verify that there were
          * no actual errors, even if the returned value was positive.
          */
         switch (cert_error) {
         case X509_V_ERR_NO_EXPLICIT_POLICY:
             policies_print(ctx);
             /* fall thru */
         case X509_V_ERR_CERT_HAS_EXPIRED:
             /* Continue even if the leaf is a self-signed cert */
         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_CRL_HAS_EXPIRED:
         case X509_V_ERR_CRL_NOT_YET_VALID:
         case X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION:
             /* errors due to strict conformance checking (-x509_strict) */
         case X509_V_ERR_INVALID_PURPOSE:
         case X509_V_ERR_PATHLEN_INVALID_FOR_NON_CA:
         case X509_V_ERR_PATHLEN_WITHOUT_KU_KEY_CERT_SIGN:
         case X509_V_ERR_CA_BCONS_NOT_CRITICAL:
         case X509_V_ERR_CA_CERT_MISSING_KEY_USAGE:
         case X509_V_ERR_KU_KEY_CERT_SIGN_INVALID_FOR_NON_CA:
         case X509_V_ERR_ISSUER_NAME_EMPTY:
         case X509_V_ERR_SUBJECT_NAME_EMPTY:
         case X509_V_ERR_EMPTY_SUBJECT_SAN_NOT_CRITICAL:
         case X509_V_ERR_EMPTY_SUBJECT_ALT_NAME:
         case X509_V_ERR_SIGNATURE_ALGORITHM_INCONSISTENCY:
         case X509_V_ERR_AUTHORITY_KEY_IDENTIFIER_CRITICAL:
         case X509_V_ERR_SUBJECT_KEY_IDENTIFIER_CRITICAL:
         case X509_V_ERR_MISSING_AUTHORITY_KEY_IDENTIFIER:
         case X509_V_ERR_MISSING_SUBJECT_KEY_IDENTIFIER:
         case X509_V_ERR_EXTENSIONS_REQUIRE_VERSION_3:
             ok = 1;
         }
         return ok;

     }
     if (cert_error == X509_V_OK && ok == 2)
         policies_print(ctx);
     if (!v_verbose)
         ERR_clear_error();
     return ok;
 }
	/*
	* Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
	*
	* Licensed under the Apache License 2.0 (the "License"). You may not use
	* this file except in compliance with the License. You can obtain a copy
	* in the file LICENSE in the source distribution or at
	* https://www.openssl.org/source/license.html
	*/

	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include "apps.h"
	#include "progs.h"
	#include <openssl/bio.h>
	#include <openssl/err.h>
	#include <openssl/x509.h>
	#include <openssl/x509v3.h>
	#include <openssl/pem.h>

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

	typedef enum OPTION_choice {
	OPT_COMMON,
	OPT_ENGINE, OPT_CAPATH, OPT_CAFILE, OPT_CASTORE,
	OPT_NOCAPATH, OPT_NOCAFILE, OPT_NOCASTORE,
	OPT_UNTRUSTED, OPT_TRUSTED, OPT_CRLFILE, OPT_CRL_DOWNLOAD, OPT_SHOW_CHAIN,
	OPT_V_ENUM, OPT_NAMEOPT, OPT_VFYOPT,
	OPT_VERBOSE,
	OPT_PROV_ENUM
	} OPTION_CHOICE;

	const OPTIONS verify_options[] = {
	{OPT_HELP_STR, 1, '-', "Usage: %s [options] [cert...]\n"},

	OPT_SECTION("General"),
	{"help", OPT_HELP, '-', "Display this summary"},
	#ifndef OPENSSL_NO_ENGINE
	{"engine", OPT_ENGINE, 's', "Use engine, possibly a hardware device"},
	#endif
	{"verbose", OPT_VERBOSE, '-',
	"Print extra information about the operations being performed."},
	{"nameopt", OPT_NAMEOPT, 's', "Certificate subject/issuer name printing options"},

	OPT_SECTION("Certificate chain"),
	{"trusted", OPT_TRUSTED, '<', "A file of trusted certificates"},
	{"CAfile", OPT_CAFILE, '<', "A file of trusted certificates"},
	{"CApath", OPT_CAPATH, '/', "A directory of files with trusted certificates"},
	{"CAstore", OPT_CASTORE, ':', "URI to a store of trusted certificates"},
	{"no-CAfile", OPT_NOCAFILE, '-',
	"Do not load the default trusted certificates file"},
	{"no-CApath", OPT_NOCAPATH, '-',
	"Do not load trusted certificates from the default directory"},
	{"no-CAstore", OPT_NOCASTORE, '-',
	"Do not load trusted certificates from the default certificates store"},
	{"untrusted", OPT_UNTRUSTED, '<', "A file of untrusted certificates"},
	{"CRLfile", OPT_CRLFILE, '<',
	"File containing one or more CRL's (in PEM format) to load"},
	{"crl_download", OPT_CRL_DOWNLOAD, '-',
	"Try downloading CRL information for certificates via their CDP entries"},
	{"show_chain", OPT_SHOW_CHAIN, '-',
	"Display information about the certificate chain"},

	OPT_V_OPTIONS,
	{"vfyopt", OPT_VFYOPT, 's', "Verification parameter in n:v form"},

	OPT_PROV_OPTIONS,

	OPT_PARAMETERS(),
	{"cert", 0, 0, "Certificate(s) to verify (optional; stdin used otherwise)"},
	{NULL}
	};

	int verify_main(int argc, char **argv)
	{
	ENGINE *e = NULL;
	STACK_OF(X509) untrusted = NULL, trusted = NULL;
	STACK_OF(X509_CRL) *crls = NULL;
	STACK_OF(OPENSSL_STRING) *vfyopts = NULL;
	X509_STORE *store = NULL;
	X509_VERIFY_PARAM *vpm = NULL;
	const char prog, CApath = NULL, CAfile = NULL, CAstore = NULL;
	int noCApath = 0, noCAfile = 0, noCAstore = 0;
	int vpmtouched = 0, crl_download = 0, show_chain = 0, i = 0, ret = 1;
	OPTION_CHOICE o;

	if ((vpm = X509_VERIFY_PARAM_new()) == NULL)
	goto end;

	prog = opt_init(argc, argv, verify_options);
	while ((o = opt_next()) != OPT_EOF) {
	switch (o) {
	case OPT_EOF:
	case OPT_ERR:
	opthelp:
	BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
	goto end;
	case OPT_HELP:
	opt_help(verify_options);
	BIO_printf(bio_err, "\nRecognized certificate chain purposes:\n");
	for (i = 0; i < X509_PURPOSE_get_count(); i++) {
	X509_PURPOSE *ptmp = X509_PURPOSE_get0(i);

	BIO_printf(bio_err, " %-15s %s\n",
	X509_PURPOSE_get0_sname(ptmp),
	X509_PURPOSE_get0_name(ptmp));
	}

	BIO_printf(bio_err, "Recognized certificate policy names:\n");
	for (i = 0; i < X509_VERIFY_PARAM_get_count(); i++) {
	const X509_VERIFY_PARAM *vptmp = X509_VERIFY_PARAM_get0(i);

	BIO_printf(bio_err, " %s\n",
	X509_VERIFY_PARAM_get0_name(vptmp));
	}
	ret = 0;
	goto end;
	case OPT_V_CASES:
	if (!opt_verify(o, vpm))
	goto end;
	vpmtouched++;
	break;
	case OPT_CAPATH:
	CApath = opt_arg();
	break;
	case OPT_CAFILE:
	CAfile = opt_arg();
	break;
	case OPT_CASTORE:
	CAstore = opt_arg();
	break;
	case OPT_NOCAPATH:
	noCApath = 1;
	break;
	case OPT_NOCAFILE:
	noCAfile = 1;
	break;
	case OPT_NOCASTORE:
	noCAstore = 1;
	break;
	case OPT_UNTRUSTED:
	/* Zero or more times */
	if (!load_certs(opt_arg(), 0, &untrusted, NULL,
	"untrusted certificates"))
	goto end;
	break;
	case OPT_TRUSTED:
	/* Zero or more times */
	noCAfile = 1;
	noCApath = 1;
	noCAstore = 1;
	if (!load_certs(opt_arg(), 0, &trusted, NULL, "trusted certificates"))
	goto end;
	break;
	case OPT_CRLFILE:
	/* Zero or more times */
	if (!load_crls(opt_arg(), &crls, NULL, "other CRLs"))
	goto end;
	break;
	case OPT_CRL_DOWNLOAD:
	crl_download = 1;
	break;
	case OPT_ENGINE:
	if ((e = setup_engine(opt_arg(), 0)) == NULL) {
	/* Failure message already displayed */
	goto end;
	}
	break;
	case OPT_SHOW_CHAIN:
	show_chain = 1;
	break;
	case OPT_NAMEOPT:
	if (!set_nameopt(opt_arg()))
	goto end;
	break;
	case OPT_VFYOPT:
	if (!vfyopts)
	vfyopts = sk_OPENSSL_STRING_new_null();
	if (!vfyopts \|\| !sk_OPENSSL_STRING_push(vfyopts, opt_arg()))
	goto opthelp;
	break;
	case OPT_VERBOSE:
	v_verbose = 1;
	break;
	case OPT_PROV_CASES:
	if (!opt_provider(o))
	goto end;
	break;
	}
	}

	/* Extra arguments are certificates to verify. */
	argc = opt_num_rest();
	argv = opt_rest();

	if (trusted != NULL
	&& (CAfile != NULL \|\| CApath != NULL \|\| CAstore != NULL)) {
	BIO_printf(bio_err,
	"%s: Cannot use -trusted with -CAfile, -CApath or -CAstore\n",
	prog);
	goto end;
	}

	if ((store = setup_verify(CAfile, noCAfile, CApath, noCApath,
	CAstore, noCAstore)) == NULL)
	goto end;
	X509_STORE_set_verify_cb(store, cb);

	if (vpmtouched)
	X509_STORE_set1_param(store, vpm);

	ERR_clear_error();

	if (crl_download)
	store_setup_crl_download(store);

	ret = 0;
	if (argc < 1) {
	if (check(store, NULL, untrusted, trusted, crls, show_chain,
	vfyopts) != 1)
	ret = -1;
	} else {
	for (i = 0; i < argc; i++)
	if (check(store, argv[i], untrusted, trusted, crls, show_chain,
	vfyopts) != 1)
	ret = -1;
	}

	end:
	X509_VERIFY_PARAM_free(vpm);
	X509_STORE_free(store);
	sk_X509_pop_free(untrusted, X509_free);
	sk_X509_pop_free(trusted, X509_free);
	sk_X509_CRL_pop_free(crls, X509_CRL_free);
	sk_OPENSSL_STRING_free(vfyopts);
	release_engine(e);
	return (ret < 0 ? 2 : ret);
	}

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

	x = load_cert(file, FORMAT_UNDEF, "certificate file");
	if (x == NULL)
	goto end;

	if (opts != NULL) {
	for (i = 0; i < sk_OPENSSL_STRING_num(opts); i++) {
	char *opt = sk_OPENSSL_STRING_value(opts, i);
	if (x509_ctrl_string(x, opt) <= 0) {
	BIO_printf(bio_err, "parameter error \"%s\"\n", opt);
	ERR_print_errors(bio_err);
	return 0;
	}
	}
	}

	csc = X509_STORE_CTX_new();
	if (csc == NULL) {
	BIO_printf(bio_err, "error %s: X.509 store context allocation failed\n",
	(file == NULL) ? "stdin" : file);
	goto end;
	}

	X509_STORE_set_flags(ctx, vflags);
	if (!X509_STORE_CTX_init(csc, ctx, x, uchain)) {
	X509_STORE_CTX_free(csc);
	BIO_printf(bio_err,
	"error %s: X.509 store context initialization failed\n",
	(file == NULL) ? "stdin" : file);
	goto end;
	}
	if (tchain != NULL)
	X509_STORE_CTX_set0_trusted_stack(csc, tchain);
	if (crls != NULL)
	X509_STORE_CTX_set0_crls(csc, crls);
	i = X509_verify_cert(csc);
	if (i > 0 && X509_STORE_CTX_get_error(csc) == X509_V_OK) {
	BIO_printf(bio_out, "%s: OK\n", (file == NULL) ? "stdin" : file);
	ret = 1;
	if (show_chain) {
	int j;

	chain = X509_STORE_CTX_get1_chain(csc);
	num_untrusted = X509_STORE_CTX_get_num_untrusted(csc);
	BIO_printf(bio_out, "Chain:\n");
	for (j = 0; j < sk_X509_num(chain); j++) {
	X509 *cert = sk_X509_value(chain, j);
	BIO_printf(bio_out, "depth=%d: ", j);
	X509_NAME_print_ex_fp(stdout,
	X509_get_subject_name(cert),
	0, get_nameopt());
	if (j < num_untrusted)
	BIO_printf(bio_out, " (untrusted)");
	BIO_printf(bio_out, "\n");
	}
	sk_X509_pop_free(chain, X509_free);
	}
	} else {
	BIO_printf(bio_err,
	"error %s: verification failed\n",
	(file == NULL) ? "stdin" : file);
	}
	X509_STORE_CTX_free(csc);

	end:
	if (i <= 0)
	ERR_print_errors(bio_err);
	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 != NULL) {
	X509_NAME_print_ex(bio_err,
	X509_get_subject_name(current_cert),
	0, get_nameopt());
	BIO_printf(bio_err, "\n");
	}
	BIO_printf(bio_err, "%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));

	/*
	* Pretend that some errors are ok, so they don't stop further
	* processing of the certificate chain. Setting ok = 1 does this.
	* After X509_verify_cert() is done, we verify that there were
	* no actual errors, even if the returned value was positive.
	*/
	switch (cert_error) {
	case X509_V_ERR_NO_EXPLICIT_POLICY:
	policies_print(ctx);
	/* fall thru */
	case X509_V_ERR_CERT_HAS_EXPIRED:
	/* Continue even if the leaf is a self-signed cert */
	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_CRL_HAS_EXPIRED:
	case X509_V_ERR_CRL_NOT_YET_VALID:
	case X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION:
	/* errors due to strict conformance checking (-x509_strict) */
	case X509_V_ERR_INVALID_PURPOSE:
	case X509_V_ERR_PATHLEN_INVALID_FOR_NON_CA:
	case X509_V_ERR_PATHLEN_WITHOUT_KU_KEY_CERT_SIGN:
	case X509_V_ERR_CA_BCONS_NOT_CRITICAL:
	case X509_V_ERR_CA_CERT_MISSING_KEY_USAGE:
	case X509_V_ERR_KU_KEY_CERT_SIGN_INVALID_FOR_NON_CA:
	case X509_V_ERR_ISSUER_NAME_EMPTY:
	case X509_V_ERR_SUBJECT_NAME_EMPTY:
	case X509_V_ERR_EMPTY_SUBJECT_SAN_NOT_CRITICAL:
	case X509_V_ERR_EMPTY_SUBJECT_ALT_NAME:
	case X509_V_ERR_SIGNATURE_ALGORITHM_INCONSISTENCY:
	case X509_V_ERR_AUTHORITY_KEY_IDENTIFIER_CRITICAL:
	case X509_V_ERR_SUBJECT_KEY_IDENTIFIER_CRITICAL:
	case X509_V_ERR_MISSING_AUTHORITY_KEY_IDENTIFIER:
	case X509_V_ERR_MISSING_SUBJECT_KEY_IDENTIFIER:
	case X509_V_ERR_EXTENSIONS_REQUIRE_VERSION_3:
	ok = 1;
	}
	return ok;

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