From 011f6ad2001f2bded2c41ec4b3771bdc7ba0ebe5 Mon Sep 17 00:00:00 2001
From: terrafrost <terrafrost@php.net>
Date: Tue, 3 Apr 2018 20:23:47 -0500
Subject: [PATCH] BigInteger/PHP: make sure that zero is represented uniformly

---
 phpseclib/Math/BigInteger/Engines/PHP.php | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/phpseclib/Math/BigInteger/Engines/PHP.php b/phpseclib/Math/BigInteger/Engines/PHP.php
index 1ec77e24..697fa94c 100644
--- a/phpseclib/Math/BigInteger/Engines/PHP.php
+++ b/phpseclib/Math/BigInteger/Engines/PHP.php
@@ -108,6 +108,10 @@ abstract class PHP extends Engine
                 while (strlen($x)) {
                     $this->value[] = self::bytes2int(self::base256_rshift($x, static::BASE));
                 }
+
+                if ($this->value == [0]) {
+                    $this->value = [];
+                }
                 break;
             case 16:
                 $x = (strlen($this->value) & 1) ? '0' . $this->value : $this->value;