From b6d0e37432a88dfd54b6779945ba379531a6eaf4 Mon Sep 17 00:00:00 2001
From: terrafrost <terrafrost@php.net>
Date: Sun, 10 Sep 2017 14:56:57 -0500
Subject: [PATCH] BigInteger: use gmp_import / gmp_export when available

---
 phpseclib/Math/BigInteger.php | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/phpseclib/Math/BigInteger.php b/phpseclib/Math/BigInteger.php
index 192ce82f..54bff85c 100644
--- a/phpseclib/Math/BigInteger.php
+++ b/phpseclib/Math/BigInteger.php
@@ -360,8 +360,12 @@ class Math_BigInteger
             case 256:
                 switch (MATH_BIGINTEGER_MODE) {
                     case MATH_BIGINTEGER_MODE_GMP:
-                        $sign = $this->is_negative ? '-' : '';
-                        $this->value = gmp_init($sign . '0x' . bin2hex($x));
+                        $this->value = function_exists('gmp_import') ?
+                            gmp_import($x) :
+                            gmp_init('0x' . bin2hex($x));
+                        if ($this->is_negative) {
+                            $this->value = gmp_neg($this->value);
+                        }
                         break;
                     case MATH_BIGINTEGER_MODE_BCMATH:
                         // round $len to the nearest 4 (thanks, DavidMJ!)
@@ -563,9 +567,13 @@ class Math_BigInteger
                     return $this->precision > 0 ? str_repeat(chr(0), ($this->precision + 1) >> 3) : '';
                 }
 
-                $temp = gmp_strval(gmp_abs($this->value), 16);
-                $temp = (strlen($temp) & 1) ? '0' . $temp : $temp;
-                $temp = pack('H*', $temp);
+                if (function_exists('gmp_export')) {
+                    $temp = gmp_export($this->value);
+                } else {
+                    $temp = gmp_strval(gmp_abs($this->value), 16);
+                    $temp = (strlen($temp) & 1) ? '0' . $temp : $temp;
+                    $temp = pack('H*', $temp);
+                }
 
                 return $this->precision > 0 ?
                     substr(str_pad($temp, $this->precision >> 3, chr(0), STR_PAD_LEFT), -($this->precision >> 3)) :