password_get_info

(PHP 5 >= 5.5.0, PHP 7)

password_get_info — 返回指定哈希（hash）的相关信息

说明

array password_get_info ( string $hash )

如果传入的哈希（hash）是由 password_hash() 支持的算法生成的， 这个函数就会返回关于此哈希的信息数组。

参数

hash

一个由 password_hash() 创建的散列值。

返回值

返回三个元素的关联数组：

User Contributed Notes

cbungholio at gmail dot com 31-Jul-2017 10:23
If you're curious to use this method to determine if there is someway to evaluate if a given string is NOT a password_hash() value...

<?php

// Our password.. the kind of thing and idiot would have on his luggage:
$password_plaintext = "12345";

// Hash it up, fuzzball!
$password_hash = password_hash( $password_plaintext, PASSWORD_DEFAULT, [ 'cost' => 11 ] );

// What do we get?
print_r( password_get_info( $password_hash ) );

/* returns:
Array (
    [algo] => 1
    [algoName] => bcrypt  // Your server's default.
    [options] => Array ( [cost] => 11 )
)
*/

// What about if it's un-hashed?...
print_r( password_get_info( $password_plaintext ) );

/* returns:
Array (
    [algo] => 0
    [algoName] => unknown
    [options] => Array ( )
)
*/
?>

... Looks like it's up to each of us to personally decide if it's safe to compare against the final returned array.
lincoln dot du dot j at gmail dot com 16-Jul-2017 04:59
<?php

$a= password_hash("rasmuslerdorf", PASSWORD_DEFAULT);

var_dump(password_get_info($a));
//change every refresh
var_dump($a);

?>

//Output like

array(3) {
  ["algo"]=>
  int(1)
  ["algoName"]=>
  string(6) "bcrypt"
  ["options"]=>
  array(1) {
    ["cost"]=>
    int(10)
  }
}
string(60) "$2y$10$wKEZs6W//QDoOeTKSCXx7.Y9Q7duFEtJpFFuJn1G5GhyWTTit/tL2"
hej at gustav dot tv 03-Apr-2014 08:14
<?php
var_dump(password_get_info($hash));
// Example
array(3) {
  ["algo"]=>
  int(1)
  ["algoName"]=>
  string(6) "bcrypt"
  ["options"]=>
  array(1) {
    ["cost"]=>
    int(10)
  }
}

?>