PHP sha1() function

Example

Compute the SHA-1 hash of the string "Hello":

<?php$str = "Hello";echo sha1($str);?>

Definition and usage

The sha1() function calculates the SHA-1 hash of a string.

The sha1() function uses the American Secure Hash algorithm1.

Explanation from RFC 3174 - US Secure Hash Algorithm 1: SHA-1 produces a 160-bit output called the message digest. The message digest can be fed into a signature algorithm that generates or verifies the message signature. Signing the message digest instead of the message can improve process efficiency because the size of the message digest is usually much smaller than the message. The verifier of a digital signature must use the same hashing algorithm as the creator of the digital signature.

Tip: To calculate the SHA-1 hash of a file, use the sha1_file() function.

grammar

 sha1( string,raw )

parameter	describe
string	Required. Specifies the string to be calculated.
raw	Optional. Specify hexadecimal or binary output format: TRUE - raw 20-character binary format FALSE - Default. 40 character hexadecimal number

technical details

Return value:	Returns the computed SHA-1 hash on success, or FALSE on failure.
PHP version:	4.3.0+
Update log:	In PHP 5.0, the raw parameter becomes optional.

More examples

Example 1

Output the result of sha1():

<?php $str = "Hello"; echo "The string: ".$str."<br>"; echo "TRUE - Raw 20 character binary format: ".sha1($str, TRUE)."<br> "; echo "FALSE - 40 character hex number: ".sha1($str)."<br>"; ?>

Example 2

Print the result of sha1() and test it:

<?php$str = "Hello";echo sha1($str);if (sha1($str) == "f7ff9e8b7bb2e09b70935a5d785e0cc5d9d0abf0") { echo "<br>Hello world!"; exit; }?>