can be used for RSA encryption/decryption!
(PHP 4 >= 4.0.4, PHP 5, PHP 7, PHP 8)
gmp_powm — Raise number into power with modulo
Calculate (num raised into power
exponent) modulo modulus.
numThe base number.
A GMP object, an int,
or a string that can be interpreted as a number following the same logic
as if the string was used in gmp_init() with automatic
base detection (i.e. when base is equal to 0).
exponent
The positive power to raise the num.
A GMP object, an int,
or a string that can be interpreted as a number following the same logic
as if the string was used in gmp_init() with automatic
base detection (i.e. when base is equal to 0).
modulusThe modulo.
A GMP object, an int,
or a string that can be interpreted as a number following the same logic
as if the string was used in gmp_init() with automatic
base detection (i.e. when base is equal to 0).
The new (raised) number, as a GMP number.
Throws a ValueError if exponent is negative.
Throws a DivisionByZeroError if modulus
is 0.
Prior to PHP 8.0.0, an E_WARNING was raised instead.
Example #1 gmp_powm() example
<?php
$pow1 = gmp_powm("2", "31", "2147483649");
echo gmp_strval($pow1) . "\n";
?>The above example will output:
2147483648