PHP 7 - CSPRNG

In PHP 7, following two new functions are introduced to generate cryptographically secure integers and strings in a cross platform way.

random_bytes() − Generates cryptographically secure pseudo-random bytes.

random_int() − Generates cryptographically secure pseudo-random integers.

random_bytes()

random_bytes() generates an arbitrary-length string of cryptographic random bytes that are suitable for cryptographic use, such as when generating salts, keys or initiapzation vectors.

Syntax

string random_bytes ( int $length )

Parameters

length − The length of the random string that should be returned in bytes.

Return Values

Returns a string containing the requested number of cryptographically secure random bytes.

Errors/Exceptions

If an appropriate source of randomness cannot be found, an Exception will be thrown.

If invapd parameters are given, a TypeError will be thrown.

If an invapd length of bytes is given, an Error will be thrown.

Example

<?php
   $bytes = random_bytes(5);
   print(bin2hex($bytes));
?>

54cc305593

int random_int ( int $min , int $max )

<?php
   print(random_int(100, 999));
   print("");
   print(random_int(-1000, 0));
?>

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