root/ext/standard/password.c

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DEFINITIONS

This source file includes following definitions.
  1. PHP_MINIT_FUNCTION
  2. php_password_get_algo_name
  3. php_password_determine_algo
  4. php_password_salt_is_alphabet
  5. php_password_salt_to64
  6. php_password_make_salt
  7. PHP_FUNCTION
  8. PHP_FUNCTION
  9. PHP_FUNCTION
  10. PHP_FUNCTION

/*
   +----------------------------------------------------------------------+
   | PHP Version 5                                                        |
   +----------------------------------------------------------------------+
   | Copyright (c) 1997-2013 The PHP Group                                |
   +----------------------------------------------------------------------+
   | This source file is subject to version 3.01 of the PHP license,      |
   | that is bundled with this package in the file LICENSE, and is        |
   | available through the world-wide-web at the following url:           |
   | http://www.php.net/license/3_01.txt                                  |
   | If you did not receive a copy of the PHP license and are unable to   |
   | obtain it through the world-wide-web, please send a note to          |
   | license@php.net so we can mail you a copy immediately.               |
   +----------------------------------------------------------------------+
   | Authors: Anthony Ferrara <ircmaxell@php.net>                         |
   +----------------------------------------------------------------------+
*/

/* $Id$ */

#include <stdlib.h>

#include "php.h"
#if HAVE_CRYPT

#include "fcntl.h"
#include "php_password.h"
#include "php_rand.h"
#include "php_crypt.h"
#include "base64.h"
#include "zend_interfaces.h"
#include "info.h"

#if PHP_WIN32
#include "win32/winutil.h"
#endif

PHP_MINIT_FUNCTION(password) /* {{{ */
{
        REGISTER_LONG_CONSTANT("PASSWORD_DEFAULT", PHP_PASSWORD_DEFAULT, CONST_CS | CONST_PERSISTENT);
        REGISTER_LONG_CONSTANT("PASSWORD_BCRYPT", PHP_PASSWORD_BCRYPT, CONST_CS | CONST_PERSISTENT);

        REGISTER_LONG_CONSTANT("PASSWORD_BCRYPT_DEFAULT_COST", PHP_PASSWORD_BCRYPT_COST, CONST_CS | CONST_PERSISTENT);

        return SUCCESS;
}
/* }}} */

static char* php_password_get_algo_name(const php_password_algo algo)
{
        switch (algo) {
                case PHP_PASSWORD_BCRYPT:
                        return "bcrypt";
                case PHP_PASSWORD_UNKNOWN:
                default:
                        return "unknown";
        }
}

static php_password_algo php_password_determine_algo(const char *hash, const size_t len) 
{
        if (len > 3 && hash[0] == '$' && hash[1] == '2' && hash[2] == 'y' && len == 60) {
                return PHP_PASSWORD_BCRYPT;
        }

        return PHP_PASSWORD_UNKNOWN;
}

static int php_password_salt_is_alphabet(const char *str, const size_t len) /* {{{ */
{
        size_t i = 0;

        for (i = 0; i < len; i++) {
                if (!((str[i] >= 'A' && str[i] <= 'Z') || (str[i] >= 'a' && str[i] <= 'z') || (str[i] >= '0' && str[i] <= '9') || str[i] == '.' || str[i] == '/')) {
                        return FAILURE;
                }
        }
        return SUCCESS;
}
/* }}} */

static int php_password_salt_to64(const char *str, const size_t str_len, const size_t out_len, char *ret) /* {{{ */
{
        size_t pos = 0;
        size_t ret_len = 0;
        unsigned char *buffer;
        if ((int) str_len < 0) {
                return FAILURE;
        }
        buffer = php_base64_encode((unsigned char*) str, (int) str_len, (int*) &ret_len);
        if (ret_len < out_len) {
                /* Too short of an encoded string generated */
                efree(buffer);
                return FAILURE;
        }
        for (pos = 0; pos < out_len; pos++) {
                if (buffer[pos] == '+') {
                        ret[pos] = '.';
                } else if (buffer[pos] == '=') {
                        efree(buffer);
                        return FAILURE;
                } else {
                        ret[pos] = buffer[pos];
                }
        }
        efree(buffer);
        return SUCCESS;
}
/* }}} */

static int php_password_make_salt(size_t length, char *ret TSRMLS_DC) /* {{{ */
{
        int buffer_valid = 0;
        size_t i, raw_length;
        char *buffer;
        char *result;

        if (length > (INT_MAX / 3)) {
                php_error_docref(NULL TSRMLS_CC, E_WARNING, "Length is too large to safely generate");
                return FAILURE;
        }

        raw_length = length * 3 / 4 + 1;

        buffer = (char *) safe_emalloc(raw_length, 1, 1);

#if PHP_WIN32
        {
                BYTE *iv_b = (BYTE *) buffer;
                if (php_win32_get_random_bytes(iv_b, raw_length) == SUCCESS) {
                        buffer_valid = 1;
                }
        }
#else
        {
                int fd, n;
                size_t read_bytes = 0;
                fd = open("/dev/urandom", O_RDONLY);
                if (fd >= 0) {
                        while (read_bytes < raw_length) {
                                n = read(fd, buffer + read_bytes, raw_length - read_bytes);
                                if (n < 0) {
                                        break;
                                }
                                read_bytes += (size_t) n;
                        }
                        close(fd);
                }
                if (read_bytes >= raw_length) {
                        buffer_valid = 1;
                }
        }
#endif
        if (!buffer_valid) {
                for (i = 0; i < raw_length; i++) {
                        buffer[i] ^= (char) (255.0 * php_rand(TSRMLS_C) / RAND_MAX);
                }
        }

        result = safe_emalloc(length, 1, 1); 
        if (php_password_salt_to64(buffer, raw_length, length, result) == FAILURE) {
                php_error_docref(NULL TSRMLS_CC, E_WARNING, "Generated salt too short");
                efree(buffer);
                efree(result);
                return FAILURE;
        }
        memcpy(ret, result, (int) length);
        efree(result);
        efree(buffer);
        ret[length] = 0;
        return SUCCESS;
}
/* }}} */

PHP_FUNCTION(password_get_info)
{
        php_password_algo algo;
        int hash_len;
        char *hash, *algo_name;
        zval *options;

        if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s", &hash, &hash_len) == FAILURE) {
                return;
        }

        if (hash_len < 0 || (size_t) hash_len < 0) {
                php_error_docref(NULL TSRMLS_CC, E_WARNING, "Supplied password hash too long to safely identify");
                RETURN_FALSE;
        }

        ALLOC_INIT_ZVAL(options);
        array_init(options);

        algo = php_password_determine_algo(hash, (size_t) hash_len);
        algo_name = php_password_get_algo_name(algo);
        
        switch (algo) {
                case PHP_PASSWORD_BCRYPT:
                        {
                                long cost = PHP_PASSWORD_BCRYPT_COST;
                                sscanf(hash, "$2y$%ld$", &cost);
                                add_assoc_long(options, "cost", cost);
                        }
                        break;
                case PHP_PASSWORD_UNKNOWN:
                default:
                        break;
        }

        array_init(return_value);
        
        add_assoc_long(return_value, "algo", algo);
        add_assoc_string(return_value, "algoName", algo_name, 1);
        add_assoc_zval(return_value, "options", options);       
}

PHP_FUNCTION(password_needs_rehash)
{
        long new_algo = 0;
        php_password_algo algo;
        int hash_len;
        char *hash;
        HashTable *options = 0;
        zval **option_buffer;
        
        if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "sl|H", &hash, &hash_len, &new_algo, &options) == FAILURE) {
                return;
        }

        if (hash_len < 0) {
                php_error_docref(NULL TSRMLS_CC, E_WARNING, "Supplied password hash too long to safely identify");
                RETURN_FALSE;
        }

        algo = php_password_determine_algo(hash, (size_t) hash_len);
        
        if (algo != new_algo) {
                RETURN_TRUE;
        }

        switch (algo) {
                case PHP_PASSWORD_BCRYPT:
                        {
                                long new_cost = PHP_PASSWORD_BCRYPT_COST, cost = 0;
                                
                                if (options && zend_symtable_find(options, "cost", sizeof("cost"), (void **) &option_buffer) == SUCCESS) {
                                        if (Z_TYPE_PP(option_buffer) != IS_LONG) {
                                                zval cast_option_buffer;
                                                MAKE_COPY_ZVAL(option_buffer, &cast_option_buffer);
                                                convert_to_long(&cast_option_buffer);
                                                new_cost = Z_LVAL(cast_option_buffer);
                                                zval_dtor(&cast_option_buffer);
                                        } else {
                                                new_cost = Z_LVAL_PP(option_buffer);
                                        }
                                }

                                sscanf(hash, "$2y$%ld$", &cost);
                                if (cost != new_cost) {
                                        RETURN_TRUE;
                                }
                        }
                        break;
                case PHP_PASSWORD_UNKNOWN:
                default:
                        break;
        }
        RETURN_FALSE;
}

/* {{{ proto boolean password_make_salt(string password, string hash)
Verify a hash created using crypt() or password_hash() */
PHP_FUNCTION(password_verify)
{
        int status = 0, i;
        int password_len, hash_len;
        char *ret, *password, *hash;
        
        if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "ss", &password, &password_len, &hash, &hash_len) == FAILURE) {
                RETURN_FALSE;
        }
        if (php_crypt(password, password_len, hash, hash_len, &ret) == FAILURE) {
                RETURN_FALSE;
        }

        if (strlen(ret) != hash_len || hash_len < 13) {
                efree(ret);
                RETURN_FALSE;
        }
        
        /* We're using this method instead of == in order to provide
         * resistence towards timing attacks. This is a constant time
         * equality check that will always check every byte of both
         * values. */
        for (i = 0; i < hash_len; i++) {
                status |= (ret[i] ^ hash[i]);
        }

        efree(ret);

        RETURN_BOOL(status == 0);
        
}
/* }}} */

/* {{{ proto string password_hash(string password, int algo, array options = array())
Hash a password */
PHP_FUNCTION(password_hash)
{
        char *hash_format, *hash, *salt, *password, *result;
        long algo = 0;
        int password_len = 0, hash_len;
        size_t salt_len = 0, required_salt_len = 0, hash_format_len;
        HashTable *options = 0;
        zval **option_buffer;

        if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "sl|H", &password, &password_len, &algo, &options) == FAILURE) {
                return;
        }

        switch (algo) {
                case PHP_PASSWORD_BCRYPT:
                {
                        long cost = PHP_PASSWORD_BCRYPT_COST;
        
                        if (options && zend_symtable_find(options, "cost", 5, (void **) &option_buffer) == SUCCESS) {
                                if (Z_TYPE_PP(option_buffer) != IS_LONG) {
                                        zval cast_option_buffer;
                                        MAKE_COPY_ZVAL(option_buffer, &cast_option_buffer);
                                        convert_to_long(&cast_option_buffer);
                                        cost = Z_LVAL(cast_option_buffer);
                                        zval_dtor(&cast_option_buffer);
                                } else {
                                        cost = Z_LVAL_PP(option_buffer);
                                }
                        }
        
                        if (cost < 4 || cost > 31) {
                                php_error_docref(NULL TSRMLS_CC, E_WARNING, "Invalid bcrypt cost parameter specified: %ld", cost);
                                RETURN_NULL();
                        }
                        
                        required_salt_len = 22;
                        hash_format = emalloc(8);
                        sprintf(hash_format, "$2y$%02ld$", cost);
                        hash_format_len = 7;
                }
                break;
                case PHP_PASSWORD_UNKNOWN:
                default:
                        php_error_docref(NULL TSRMLS_CC, E_WARNING, "Unknown password hashing algorithm: %ld", algo);
                        RETURN_NULL();
        }

        if (options && zend_symtable_find(options, "salt", 5, (void**) &option_buffer) == SUCCESS) {
                char *buffer;
                int buffer_len_int = 0;
                size_t buffer_len;
                switch (Z_TYPE_PP(option_buffer)) {
                        case IS_STRING:
                                buffer = estrndup(Z_STRVAL_PP(option_buffer), Z_STRLEN_PP(option_buffer));
                                buffer_len_int = Z_STRLEN_PP(option_buffer);
                                break;
                        case IS_LONG:
                        case IS_DOUBLE:
                        case IS_OBJECT: {
                                zval cast_option_buffer;
                                MAKE_COPY_ZVAL(option_buffer, &cast_option_buffer);
                                convert_to_string(&cast_option_buffer);
                                if (Z_TYPE(cast_option_buffer) == IS_STRING) {
                                        buffer = estrndup(Z_STRVAL(cast_option_buffer), Z_STRLEN(cast_option_buffer));
                                        buffer_len_int = Z_STRLEN(cast_option_buffer);
                                        zval_dtor(&cast_option_buffer);
                                        break;
                                }
                                zval_dtor(&cast_option_buffer);
                        }
                        case IS_BOOL:
                        case IS_NULL:
                        case IS_RESOURCE:
                        case IS_ARRAY:
                        default:
                                efree(hash_format);
                                php_error_docref(NULL TSRMLS_CC, E_WARNING, "Non-string salt parameter supplied");
                                RETURN_NULL();
                }
                if (buffer_len_int < 0) {
                        efree(hash_format);
                        efree(buffer);
                        php_error_docref(NULL TSRMLS_CC, E_WARNING, "Supplied salt is too long");
                }
                buffer_len = (size_t) buffer_len_int;
                if (buffer_len < required_salt_len) {
                        efree(hash_format);
                        efree(buffer);
                        php_error_docref(NULL TSRMLS_CC, E_WARNING, "Provided salt is too short: %lu expecting %lu", (unsigned long) buffer_len, (unsigned long) required_salt_len);
                        RETURN_NULL();
                } else if (php_password_salt_is_alphabet(buffer, buffer_len) == FAILURE) {
                        salt = safe_emalloc(required_salt_len, 1, 1);
                        if (php_password_salt_to64(buffer, buffer_len, required_salt_len, salt) == FAILURE) {
                                efree(hash_format);
                                efree(buffer);
                                efree(salt);
                                php_error_docref(NULL TSRMLS_CC, E_WARNING, "Provided salt is too short: %lu", (unsigned long) buffer_len);
                                RETURN_NULL();
                        }
                        salt_len = required_salt_len;
                } else {
                        salt = safe_emalloc(required_salt_len, 1, 1);
                        memcpy(salt, buffer, (int) required_salt_len);
                        salt_len = required_salt_len;
                }
                efree(buffer);
        } else {
                salt = safe_emalloc(required_salt_len, 1, 1);
                if (php_password_make_salt(required_salt_len, salt TSRMLS_CC) == FAILURE) {
                        efree(hash_format);
                        efree(salt);
                        RETURN_FALSE;
                }
                salt_len = required_salt_len;
        }
        
        salt[salt_len] = 0;

        hash = safe_emalloc(salt_len + hash_format_len, 1, 1);
        sprintf(hash, "%s%s", hash_format, salt);
        hash[hash_format_len + salt_len] = 0;

        efree(hash_format);
        efree(salt);

        /* This cast is safe, since both values are defined here in code and cannot overflow */
        hash_len = (int) (hash_format_len + salt_len);

        if (php_crypt(password, password_len, hash, hash_len, &result) == FAILURE) {
                efree(hash);
                RETURN_FALSE;
        }

        efree(hash);

        if (strlen(result) < 13) {
                efree(result);
                RETURN_FALSE;
        }

        RETURN_STRING(result, 0);
}
/* }}} */

#endif /* HAVE_CRYPT */
/*
 * Local variables:
 * tab-width: 4
 * c-basic-offset: 4
 * End:
 * vim600: sw=4 ts=4 fdm=marker
 * vim<600: sw=4 ts=4
 */

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