From 3f0534134dc30c878b2e15279d2bc1d52bbfda18 Mon Sep 17 00:00:00 2001
From: orignal <i2porignal@yandex.ru>
Date: Thu, 4 Jul 2019 13:05:39 -0400
Subject: [PATCH] check for malformed b33

---
 libi2pd/Blinding.cpp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/libi2pd/Blinding.cpp b/libi2pd/Blinding.cpp
index 14852340..e51c0fcc 100644
--- a/libi2pd/Blinding.cpp
+++ b/libi2pd/Blinding.cpp
@@ -139,6 +139,11 @@ namespace data
 	{
 		uint8_t addr[40]; // TODO: define length from b33
 		size_t l = i2p::data::Base32ToByteStream (b33.c_str (), b33.length (), addr, 40);
+		if (l < 32)
+		{
+			LogPrint (eLogError, "Blinding: malformed b33 ", b33);
+			return;
+		}	
 		uint32_t checksum = crc32 (0, addr + 3, l - 3); 
 		// checksum is Little Endian
 		addr[0] ^= checksum; addr[1] ^= (checksum >> 8); addr[2] ^= (checksum >> 16);