/*

Copyright (c) 2012-2021 Roger Light <roger@atchoo.org>

All rights reserved. This program and the accompanying materials

are made available under the terms of the Eclipse Public License 2.0

and Eclipse Distribution License v1.0 which accompany this distribution.

The Eclipse Public License is available at

   https://www.eclipse.org/legal/epl-2.0/

and the Eclipse Distribution License is available at

  http://www.eclipse.org/org/documents/edl-v10.php.

SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause

Contributors:

   Roger Light - initial implementation and documentation.

*/

#include "config.h"

#include <errno.h>

#ifdef WITH_TLS

#  include <openssl/opensslv.h>

#  include <openssl/evp.h>

#  include <openssl/rand.h>

#  include <openssl/buffer.h>

#endif

#include <signal.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include "mosquitto.h"

#include "mosquitto_broker.h"

#include "password_mosq.h"

#ifdef WIN32

#  include <windows.h>

#  include <process.h>

# ifndef __cplusplus

#   if defined(_MSC_VER) && _MSC_VER < 1900

#     define bool char

#     define true 1

#     define false 0

#   else

#     include <stdbool.h>

#   endif

# endif

#   define snprintf sprintf_s

# include <io.h>

# include <windows.h>

#else

#  include <stdbool.h>

#  include <unistd.h>

#  include <termios.h>

#  include <sys/stat.h>

#endif

#ifdef WITH_TLS

int pw__hash(const char *password, struct mosquitto_pw *pw, bool new_password, int new_iterations)

{

  int rc;

  unsigned int hash_len;

  const EVP_MD *digest;

  int iterations;

#if OPENSSL_VERSION_NUMBER < 0x10100000L

  EVP_MD_CTX context;

#else

  EVP_MD_CTX *context;

#endif

  if(new_password){

    pw->salt_len = HASH_LEN;

    rc = RAND_bytes(pw->salt, (int)pw->salt_len);

    if(!rc){

      return MOSQ_ERR_UNKNOWN;

    }

    iterations = new_iterations;

  }else{

    iterations = pw->iterations;

  }

  if(iterations < 1){

    return MOSQ_ERR_INVAL;

  }

  digest = EVP_get_digestbyname("sha512");

  if(!digest){

    return MOSQ_ERR_UNKNOWN;

  }

  if(pw->hashtype == pw_sha512){

#if OPENSSL_VERSION_NUMBER < 0x10100000L

    EVP_MD_CTX_init(&context);

    EVP_DigestInit_ex(&context, digest, NULL);

    EVP_DigestUpdate(&context, password, strlen(password));

    EVP_DigestUpdate(&context, pw->salt, pw->salt_len);

    EVP_DigestFinal_ex(&context, pw->password_hash, &hash_len);

    EVP_MD_CTX_cleanup(&context);

#else

    context = EVP_MD_CTX_new();

    EVP_DigestInit_ex(context, digest, NULL);

    EVP_DigestUpdate(context, password, strlen(password));

    EVP_DigestUpdate(context, pw->salt, pw->salt_len);

    EVP_DigestFinal_ex(context, pw->password_hash, &hash_len);

    EVP_MD_CTX_free(context);

#endif

  }else{

    pw->iterations = iterations;

    hash_len = sizeof(pw->password_hash);

    PKCS5_PBKDF2_HMAC(password, (int)strlen(password),

      pw->salt, (int)pw->salt_len, iterations,

      digest, (int)hash_len, pw->password_hash);

  }

  return MOSQ_ERR_SUCCESS;

}

#endif

int pw__memcmp_const(const void *a, const void *b, size_t len)

{

  size_t i;

  int rc = 0;

  if(!a || !b) return 1;

  for(i=0; i<len; i++){

    if( ((char *)a)[i] != ((char *)b)[i] ){

      rc = 1;

    }

  }

  return rc;

}