/*
  *  Copyright (C) 2014 Cisco and/or its affiliates. All rights reserved.
  *
  *  Author: Shawn Webb
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License version 2 as
  *  published by the Free Software Foundation.
  *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU General Public License for more details.
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  *  MA 02110-1301, USA.
  */
 
 #if HAVE_CONFIG_H
 #include "clamav-config.h"
 #endif
 
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
 #include <time.h>
 
 #ifdef _WIN32
 #include <io.h>
 #endif
 
 #include <sys/types.h>
 #include <dirent.h>
 #include <sys/stat.h>
 #include <fcntl.h>
 
 #if !defined(_WIN32)
 #include <unistd.h>
 #endif
 
 #include <openssl/ssl.h>
 #include <openssl/err.h>
 #include "libclamav/crypto.h"
 
 #include "clamav.h"
 #include "default.h"
 #include "others.h"
 #include "libclamav/conv.h"
 #include "libclamav/str.h"
 
 #if defined(_WIN32)
 char * strptime(const char *buf, const char *fmt, struct tm *tm);
 #endif
 
 #if !defined(MIN)
     #define MIN(x,y) ((x)<(y)?(x):(y))
 #endif
 
 int cl_initialize_crypto(void)
 {
     SSL_load_error_strings();
     SSL_library_init();
     OpenSSL_add_all_digests();
     OpenSSL_add_all_algorithms();
     OpenSSL_add_all_ciphers();
     ERR_load_crypto_strings();
 
     return 0;
 }
 
 void cl_cleanup_crypto(void)
 {
     EVP_cleanup();
 }
 
 unsigned char *cl_hash_data(char *alg, const void *buf, size_t len, unsigned char *obuf, unsigned int *olen)
 {

     EVP_MD_CTX *ctx;

     unsigned char *ret;
     size_t mdsz;
     const EVP_MD *md;
     unsigned int i;
     size_t cur;
 
     md = EVP_get_digestbyname(alg);
     if (!(md))
         return NULL;
 
     mdsz = EVP_MD_size(md);
 
     ret = (obuf != NULL) ? obuf : (unsigned char *)malloc(mdsz);
     if (!(ret))
         return NULL;
 

     ctx = EVP_MD_CTX_create();
     if (!(ctx)) {
         if (!(obuf))
             free(ret);
 
         return NULL;
     }
 
     if (!EVP_DigestInit_ex(ctx, md, NULL)) {

         if (!(obuf))
             free(ret);
 
         if ((olen))
             *olen = 0;
 

         EVP_MD_CTX_destroy(ctx);

         return NULL;
     }
 
     cur=0;
     while (cur < len) {
         size_t todo = MIN(EVP_MD_block_size(md), len-cur);

         if (!EVP_DigestUpdate(ctx, (void *)(((unsigned char *)buf)+cur), todo)) {

             if (!(obuf))
                 free(ret);
 
             if ((olen))
                 *olen = 0;
 

             EVP_MD_CTX_destroy(ctx);

             return NULL;
         }
 
         cur += todo;
     }
 

     if (!EVP_DigestFinal_ex(ctx, ret, &i)) {

         if (!(obuf))
             free(ret);
 
         if ((olen))
             *olen = 0;
 

         EVP_MD_CTX_destroy(ctx);

         return NULL;
     }
 

     EVP_MD_CTX_destroy(ctx);

     if ((olen))
         *olen = i;
 
     return ret;
 }
 
 unsigned char *cl_hash_file_fd(int fd, char *alg, unsigned int *olen)
 {

     EVP_MD_CTX *ctx;

     const EVP_MD *md;
     unsigned char *res;
 
     md = EVP_get_digestbyname(alg);
     if (!(md))
         return NULL;
 

     ctx = EVP_MD_CTX_create();
     if (!(ctx))
         return NULL;
 
     if (!EVP_DigestInit_ex(ctx, md, NULL)) {
         EVP_MD_CTX_destroy(ctx);

         return NULL;
     }
 

     res = cl_hash_file_fd_ctx(ctx, fd, olen);
     EVP_MD_CTX_destroy(ctx);

 
     return res;
 }
 
 unsigned char *cl_hash_file_fd_ctx(EVP_MD_CTX *ctx, int fd, unsigned int *olen)
 {
     unsigned char *buf;
     unsigned char *hash;
     int mdsz;
     unsigned int hashlen;
     struct stat sb;
 
 	unsigned int blocksize;
 
 #ifdef _WIN32
     int nread;
 #else
     ssize_t nread;
 #endif
 
     mdsz = EVP_MD_CTX_size(ctx);
 
     if (fstat(fd, &sb) < 0) {
         return NULL;
     }
 
 #ifdef _WIN32
 	blocksize = 8192;
 #else
 	blocksize = sb.st_blksize;
 #endif
 
     buf = (unsigned char *)malloc(blocksize);
     if (!(buf)) {
         return NULL;
     }
 
     hash = (unsigned char *)malloc(mdsz);
     if (!(hash)) {
         free(buf);
         return NULL;
     }
 
 #ifdef _WIN32
     while ((nread = _read(fd, buf, blocksize)) > 0) {
 #else
     while ((nread = read(fd, buf, blocksize)) > 0) {
 #endif
         if (!EVP_DigestUpdate(ctx, buf, nread)) {
             free(buf);
             free(hash);
 
             return NULL;
         }
     }
 

     if (!EVP_DigestFinal_ex(ctx, hash, &hashlen)) {

         free(hash);
         free(buf);
 
         return NULL;
     }
 
     if ((olen))
         *olen = hashlen;
 
     free(buf);
 
     return hash;
 }
 
 unsigned char *cl_hash_file_fp(FILE *fp, char *alg, unsigned int *olen)
 {
     return cl_hash_file_fd(fileno(fp), alg, olen);
 }
 
 unsigned char *cl_sha256(const void *buf, size_t len, unsigned char *obuf, unsigned int *olen)
 {
     return cl_hash_data("sha256", buf, len, obuf, olen);
 }
 
 unsigned char *cl_sha1(const void *buf, size_t len, unsigned char *obuf, unsigned int *olen)
 {
     return cl_hash_data("sha1", buf, len, obuf, olen);
 }
 
 int cl_verify_signature_hash(EVP_PKEY *pkey, char *alg, unsigned char *sig, unsigned int siglen, unsigned char *digest)
 {

     EVP_MD_CTX *ctx;

     const EVP_MD *md;
     size_t mdsz;
 
     md = EVP_get_digestbyname(alg);
     if (!(md))
         return -1;
 

     ctx = EVP_MD_CTX_create();
     if (!(ctx))
         return -1;
 

     mdsz = EVP_MD_size(md);
 

     if (!EVP_VerifyInit_ex(ctx, md, NULL)) {
         EVP_MD_CTX_destroy(ctx);

         return -1;
     }
 

     if (!EVP_VerifyUpdate(ctx, digest, mdsz)) {
         EVP_MD_CTX_destroy(ctx);

         return -1;
     }
 

     if (EVP_VerifyFinal(ctx, sig, siglen, pkey) != 0) {
         EVP_MD_CTX_destroy(ctx);

         return -1;
     }
 

     EVP_MD_CTX_destroy(ctx);

     return 0;
 }
 
 int cl_verify_signature_fd(EVP_PKEY *pkey, char *alg, unsigned char *sig, unsigned int siglen, int fd)
 {

     EVP_MD_CTX *ctx;

     const EVP_MD *md;
     size_t mdsz;
     unsigned char *digest;
 
     digest = cl_hash_file_fd(fd, alg, NULL);
     if (!(digest))
         return -1;
 
     md = EVP_get_digestbyname(alg);

     if (!(md)) {
         free(digest);

         return -1;

     }

 
     mdsz = EVP_MD_size(md);
 

     ctx = EVP_MD_CTX_create();
     if (!(ctx)) {

         free(digest);
         return -1;
     }
 

     if (!EVP_VerifyInit_ex(ctx, md, NULL)) {

         free(digest);

         EVP_MD_CTX_destroy(ctx);

         return -1;
     }
 

     if (!EVP_VerifyUpdate(ctx, digest, mdsz)) {

         free(digest);

         EVP_MD_CTX_destroy(ctx);
         return -1;
     }
 
     if (EVP_VerifyFinal(ctx, sig, siglen, pkey) != 0) {
         free(digest);
         EVP_MD_CTX_destroy(ctx);

         return -1;
     }
 
     free(digest);

     EVP_MD_CTX_destroy(ctx);

     return 0;
 }
 
 int cl_verify_signature(EVP_PKEY *pkey, char *alg, unsigned char *sig, unsigned int siglen, unsigned char *data, size_t datalen, int decode)
 {

     EVP_MD_CTX *ctx;

     const EVP_MD *md;
     size_t mdsz;
     unsigned char *digest;
 
     if (decode) {
         unsigned char *newsig;
         size_t newsiglen;
 
         newsig = (unsigned char *)cl_base64_decode((char *)sig, siglen, NULL, &newsiglen);
         if (!(newsig))
             return -1;
 
         sig = newsig;
         siglen = newsiglen;
     }
 
     digest = cl_hash_data(alg, data, datalen, NULL, NULL);
     if (!(digest)) {
         if (decode)
             free(sig);
 
         return -1;
     }
 
     md = EVP_get_digestbyname(alg);
     if (!(md)) {
         free(digest);
         if (decode)
             free(sig);
 
         return -1;
     }
 
     mdsz = EVP_MD_size(md);
 

     ctx = EVP_MD_CTX_create();
     if (!(ctx)) {
         free(digest);
         if (decode)
             free(sig);
 
         return -1;
     }
 
     if (!EVP_VerifyInit_ex(ctx, md, NULL)) {

         free(digest);
         if (decode)
             free(sig);
 

         EVP_MD_CTX_destroy(ctx);

         return -1;
     }
 

     if (!EVP_VerifyUpdate(ctx, digest, mdsz)) {

         free(digest);
         if (decode)
             free(sig);
 

         EVP_MD_CTX_destroy(ctx);

         return -1;
     }
 

     if (EVP_VerifyFinal(ctx, sig, siglen, pkey) != 0) {

         free(digest);
         if (decode)
             free(sig);
 

         EVP_MD_CTX_destroy(ctx);

         return -1;
     }
 
     if (decode)
         free(sig);
 
     free(digest);

     EVP_MD_CTX_destroy(ctx);

     return 0;
 }
 
 int cl_verify_signature_hash_x509_keyfile(char *x509path, char *alg, unsigned char *sig, unsigned int siglen, unsigned char *digest)
 {
     X509 *x509;
     FILE *fp;
     int res;
 
     fp = fopen(x509path, "r");
     if (!(fp)) {
         return -1;
     }
 
     x509 = PEM_read_X509(fp, NULL, NULL, NULL);
     if (!(x509)) {
         fclose(fp);
         return -1;
     }
 
     fclose(fp);
 
     res = cl_verify_signature_hash_x509(x509, alg, sig, siglen, digest);
 
     X509_free(x509);
 
     return res;
 }
 
 int cl_verify_signature_fd_x509_keyfile(char *x509path, char *alg, unsigned char *sig, unsigned int siglen, int fd)
 {
     X509 *x509;
     FILE *fp;
     int res;
 
     fp = fopen(x509path, "r");
     if (!(fp)) {
         return -1;
     }
 
     x509 = PEM_read_X509(fp, NULL, NULL, NULL);
     if (!(x509)) {
         fclose(fp);
         return -1;
     }
 
     fclose(fp);
 
     res = cl_verify_signature_fd_x509(x509, alg, sig, siglen, fd);
 
     X509_free(x509);
 
     return res;
 }
 
 int cl_verify_signature_x509_keyfile(char *x509path, char *alg, unsigned char *sig, unsigned int siglen, unsigned char *data, size_t datalen, int decode)
 {
     X509 *x509;
     FILE *fp;
     int res;
 
     fp = fopen(x509path, "r");
     if (!(fp)) {
         return -1;
     }
 
     x509 = PEM_read_X509(fp, NULL, NULL, NULL);
     if (!(x509)) {
         fclose(fp);
         return -1;
     }
 
     fclose(fp);
 
     res = cl_verify_signature_x509(x509, alg, sig, siglen, data, datalen, decode);
 
     X509_free(x509);
 
     return res;
 }
 
 int cl_verify_signature_hash_x509(X509 *x509, char *alg, unsigned char *sig, unsigned int siglen, unsigned char *digest)
 {
     EVP_PKEY *pkey;
     int res;
 
     pkey = X509_get_pubkey(x509);
     if (!(pkey))
         return -1;
 
     res = cl_verify_signature_hash(pkey, alg, sig, siglen, digest);
 
     EVP_PKEY_free(pkey);
 
     return res;
 }
 
 int cl_verify_signature_fd_x509(X509 *x509, char *alg, unsigned char *sig, unsigned int siglen, int fd)
 {
     EVP_PKEY *pkey;
     int res;
 
     pkey = X509_get_pubkey(x509);
     if (!(pkey))
         return -1;
 
     res = cl_verify_signature_fd(pkey, alg, sig, siglen, fd);
 
     EVP_PKEY_free(pkey);
 
     return res;
 }
 
 int cl_verify_signature_x509(X509 *x509, char *alg, unsigned char *sig, unsigned int siglen, unsigned char *data, size_t datalen, int decode)
 {
     EVP_PKEY *pkey;
     int res;
 
     pkey = X509_get_pubkey(x509);
     if (!(pkey))
         return -1;
 
     res = cl_verify_signature(pkey, alg, sig, siglen, data, datalen, decode);
 
     EVP_PKEY_free(pkey);
 
     return res;
 }
 
 unsigned char *cl_sign_data_keyfile(char *keypath, char *alg, unsigned char *hash, unsigned int *olen, int encode)
 {
     FILE *fp;
     EVP_PKEY *pkey;
     unsigned char *res;
 
     fp = fopen(keypath, "r");
     if (!(fp)) {
         return NULL;
     }
 
     pkey = PEM_read_PrivateKey(fp, NULL, NULL, NULL);
     if (!(pkey)) {
         fclose(fp);
         return NULL;
     }
 
     fclose(fp);
 
     res = cl_sign_data(pkey, alg, hash, olen, encode);
 
     EVP_PKEY_free(pkey);
 
     return res;
 }
 
 unsigned char *cl_sign_data(EVP_PKEY *pkey, char *alg, unsigned char *hash, unsigned int *olen, int encode)
 {

     EVP_MD_CTX *ctx;

     const EVP_MD *md;
     unsigned int siglen;
     unsigned char *sig;
 
     md = EVP_get_digestbyname(alg);
     if (!(md))
         return NULL;
 

     ctx = EVP_MD_CTX_create();
     if (!(ctx))
         return NULL;
 

     sig = (unsigned char *)calloc(1, EVP_PKEY_size(pkey));
     if (!(sig)) {
         free(hash);

         EVP_MD_CTX_destroy(ctx);

         return NULL;
     }
 

     if (!EVP_SignInit_ex(ctx, md, NULL)) {

         free(sig);
         free(hash);

         EVP_MD_CTX_destroy(ctx);

         return NULL;
     }
 

     if (!EVP_SignUpdate(ctx, hash, EVP_MD_size(md))) {

         free(sig);
         free(hash);

         EVP_MD_CTX_destroy(ctx);

         return NULL;
     }
 

     if (!EVP_SignFinal(ctx, sig, &siglen, pkey)) {

         free(sig);
         free(hash);

         EVP_MD_CTX_destroy(ctx);

         return NULL;
     }
 
     if (encode) {
         unsigned char *newsig = (unsigned char *)cl_base64_encode(sig, siglen);
         if (!(newsig)) {
             free(sig);
             free(hash);

             EVP_MD_CTX_destroy(ctx);

             return NULL;
         }
 
         free(sig);
         sig = newsig;
         siglen = (unsigned int)strlen((const char *)newsig);
     }
 
     free(hash);
 
     *olen = siglen;

     EVP_MD_CTX_destroy(ctx);

     return sig;
 }
 
 unsigned char *cl_sign_file_fd(int fd, EVP_PKEY *pkey, char *alg, unsigned int *olen, int encode)
 {
     unsigned char *hash, *res;
     unsigned int hashlen;
 
     hash = cl_hash_file_fd(fd, alg, &hashlen);
     if (!(hash)) {
         return NULL;
     }
 
     res = cl_sign_data(pkey, alg, hash, olen, encode);
 
     free(hash);
     return res;
 }
 
 unsigned char *cl_sign_file_fp(FILE *fp, EVP_PKEY *pkey, char *alg, unsigned int *olen, int encode)
 {
     return cl_sign_file_fd(fileno(fp), pkey, alg, olen, encode);
 }
 
 EVP_PKEY *cl_get_pkey_file(char *keypath)
 {
     EVP_PKEY *pkey;
     FILE *fp;
 
     fp = fopen(keypath, "r");
     if (!(fp))
         return NULL;
 
     if (!(pkey = PEM_read_PrivateKey(fp, NULL, NULL, NULL))) {
         fclose(fp);
         return NULL;
     }
 
     fclose(fp);
 
     return pkey;
 }
 
 X509 *cl_get_x509_from_mem(void *data, unsigned int len)
 {
     X509 *cert;
     BIO *cbio;
 
     cbio = BIO_new_mem_buf(data, len);
     if (!(cbio))
         return NULL;
 
     cert = PEM_read_bio_X509(cbio, NULL, 0, NULL);
     BIO_free(cbio);
 
     return cert;
 }
 
 int cl_validate_certificate_chain_ts_dir(char *tsdir, char *certpath)
 {
     char **authorities=NULL, **t, *fullpath;
     size_t nauths = 0;
     int res;
     DIR *dp;
     struct dirent *dirent;
 #if defined(HAVE_READDIR_R_3) || defined(HAVE_READDIR_R_2)
     union {
         struct dirent d;
         char b[offsetof(struct dirent, d_name) + NAME_MAX + 1];
     } result;
 #endif
 
     dp = opendir(tsdir);
     if (!(dp))
         return CL_EOPEN;
 
 #if defined(HAVE_READDIR_R_3)
     while (!readdir_r(dp, &result.d, &dirent) && dirent) {
 #elif defined(HAVE_READDIR_R_2)
     while ((dirent = (struct dirent *)readdir_r(dp, &result.d))) {
 #else
     while ((dirent = readdir(dp))) {
 #endif
         if (dirent->d_name[0] == '.')
             continue;
 
         if (!cli_strbcasestr(dirent->d_name, ".crt"))
             continue;
 
         t = (char **)realloc(authorities, sizeof(char **) * (nauths + 1));
         if (!(t)) {
             if (nauths) {
                 while (nauths > 0)
                     free(authorities[--nauths]);
                 free(authorities);
                 return -1;
             }
         }
 
         authorities = t;
         authorities[nauths] = (char *)malloc(strlen(tsdir) + strlen(dirent->d_name) + 2);
         if (!authorities[nauths]) {
             if (nauths) {
                 while (nauths > 0)
                     free(authorities[nauths--]);
                 free(authorities[0]);
                 free(authorities);
                 return -1;
             }
         }
 
         sprintf(authorities[nauths], "%s"PATHSEP"%s", tsdir, dirent->d_name);
         nauths++;
     }
 
     t = (char **)realloc(authorities, sizeof(char **) * (nauths + 1));
     if (!(t)) {
         if (nauths) {
             while (nauths > 0)
                 free(authorities[--nauths]);
             free(authorities);
             return -1;
         }
     }
 
     authorities = t;
     authorities[nauths] = NULL;
 
     closedir(dp);
 
     res = cl_validate_certificate_chain(authorities, NULL, certpath);
 
     while (nauths > 0)
         free(authorities[--nauths]);
     
     free(authorities);
 
     return res;
 }
 
 int cl_validate_certificate_chain(char **authorities, char *crlpath, char *certpath)
 {
     X509_STORE *store=NULL;
     X509_STORE_CTX *store_ctx;
     X509_LOOKUP *lookup=NULL;
     X509_CRL *crl=NULL;
     X509_VERIFY_PARAM *param=NULL;
     X509 *cert;
     unsigned long i;
     int res;
 
     store = X509_STORE_new();
     if (!(store)) {
         return -1;
     }
     X509_STORE_set_flags(store, 0);
 
     lookup = X509_STORE_add_lookup(store, X509_LOOKUP_file());
     if (!(lookup)) {
         X509_STORE_free(store);
         return -1;
     }
 
     if ((crlpath)) {
 
         crl = cl_load_crl(crlpath);
         if (!(crl)) {
             X509_STORE_free(store);
             return -1;
         }
 
         X509_STORE_add_crl(store, crl);
         param = X509_VERIFY_PARAM_new();
         if ((param)) {
             X509_VERIFY_PARAM_set_flags(param, X509_V_FLAG_CRL_CHECK);
             X509_STORE_set1_param(store, param);
         } else {
             X509_STORE_free(store);
             X509_CRL_free(crl);
             return -1;
         }
     }
 
     /* Support multi-tiered setups */
     for (i=0; authorities[i]; i++) {
         if (!X509_LOOKUP_load_file(lookup, authorities[i], X509_FILETYPE_PEM)) {
             X509_STORE_free(store);
             if ((crl))
                 X509_CRL_free(crl);
             if ((param))
                 X509_VERIFY_PARAM_free(param);
             return -1;
         }
     }
 
     lookup = X509_STORE_add_lookup(store, X509_LOOKUP_hash_dir());
     if (!(lookup)) {
         X509_STORE_free(store);
         if ((crl))
             X509_CRL_free(crl);
         if ((param))
             X509_VERIFY_PARAM_free(param);
         return -1;
     }
 
     X509_LOOKUP_add_dir(lookup, NULL, X509_FILETYPE_DEFAULT);
 
     store_ctx = X509_STORE_CTX_new();
     if (!(store_ctx)) {
         X509_STORE_free(store);
         if ((crl))
             X509_CRL_free(crl);
         if ((param))
             X509_VERIFY_PARAM_free(param);
         return -1;
     }
 
     cert = cl_load_cert(certpath);
     if (!(cert)) {
         X509_STORE_CTX_free(store_ctx);
         X509_STORE_free(store);
         if ((crl))
             X509_CRL_free(crl);
         if ((param))
             X509_VERIFY_PARAM_free(param);
 
         return -1;
     }
 
     if (!X509_STORE_CTX_init(store_ctx, store, cert, NULL)) {
         X509_STORE_CTX_free(store_ctx);
         X509_STORE_free(store);
         if ((crl))
             X509_CRL_free(crl);
         if ((param))
             X509_VERIFY_PARAM_free(param);
 
         X509_free(cert);
 
         return -1;
     }
 
     res = X509_verify_cert(store_ctx);
 
     X509_STORE_CTX_free(store_ctx);
     if ((crl))
         X509_CRL_free(crl);
 
     if ((param))
         X509_VERIFY_PARAM_free(param);
 
     X509_STORE_free(store);
 
     X509_free(cert);
 
     return (res > 0);
 }
 
 X509 *cl_load_cert(const char *certpath)
 {
     X509 *cert;
     BIO *bio;
 
     bio = BIO_new(BIO_s_file());
     if (!(bio))
         return NULL;
 
     if (BIO_read_filename(bio, certpath) != 1) {
         BIO_free(bio);
         return NULL;
     }
 
     cert = PEM_read_bio_X509_AUX(bio, NULL, NULL, NULL);
 
     BIO_free(bio);
 
     return cert;
 }
 
 struct tm *cl_ASN1_GetTimeT(ASN1_TIME *timeobj)
 {
     struct tm *t;
     char* str;
     size_t i = 0;
     const char *fmt;
     time_t localt;
 #ifdef _WIN32
     struct tm localtm, *ltm;
 #else
     struct tm localtm;
 #endif
 
     if (!(timeobj) || !(timeobj->data))
         return NULL;
 
     str = (char *)(timeobj->data);
     if (strlen(str) < 12)
         return NULL;
 
     t = (struct tm *)calloc(1, sizeof(struct tm));
     if (!(t))
         return NULL;
 
     if (timeobj->type == V_ASN1_UTCTIME) {
         /* two digit year */
         fmt = "%y%m%d%H%M%S";
         if (str[3] == '0') {
             str[2] = '0';
             str[3] = '9';
         } else {
             str[3]--;
         }
     }
     else if (timeobj->type == V_ASN1_GENERALIZEDTIME) {
         /* four digit year */
         fmt = "%Y%m%d%H%M%S";
         if (str[5] == '0') {
             str[4] = '0';
             str[5] = '9';
         } else {
             str[5]--;
         }
     }
 
     if (!strptime(str, fmt, t)) {
         free(t);
         return NULL;
     }
 
     /* Convert to local time */
     localt = time(NULL);
 #ifdef _WIN32
     ltm = localtime(&localt);
     memcpy((void *)(&localtm), (void *)ltm, sizeof(struct tm));
 #else
     localtime_r(&localt, &localtm);
 #endif
     t->tm_isdst = localtm.tm_isdst;
     return t;
 }
 
 X509_CRL *cl_load_crl(const char *file)
 {
     X509_CRL *x=NULL;
     FILE *fp;
     struct tm *tm;
     time_t crltime;
 
     if (!(file))
         return NULL;
 
     fp = fopen(file, "r");
     if (!(fp))
         return NULL;
 
     x = PEM_read_X509_CRL(fp, NULL, NULL, NULL);
 
     fclose(fp);
 
     if ((x)) {
         tm = cl_ASN1_GetTimeT(x->crl->nextUpdate);
         if (!(tm)) {
             X509_CRL_free(x);
             return NULL;
         }
 
 #if !defined(_WIN32)
         if (timegm(tm) < time(NULL)) {
             X509_CRL_free(x);
             free(tm);
             return NULL;
         }
 #endif
 
         free(tm);
     }
 
     return x;
 }