From 81b57141d48c86ee8ba12fdce7cff2c12504b813 Mon Sep 17 00:00:00 2001
From: orignal <romakoshelkin@yandex.ru>
Date: Tue, 6 May 2014 13:26:28 -0400
Subject: [PATCH] encrypt/decrypt same buffer

---
 aes.cpp | 20 +++++++++++++++++++-
 aes.h   |  2 ++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/aes.cpp b/aes.cpp
index 5f791271..14a5b762 100644
--- a/aes.cpp
+++ b/aes.cpp
@@ -1,3 +1,4 @@
+#include <stdlib.h>
 #include "aes.h"
 
 namespace i2p
@@ -15,16 +16,33 @@ namespace crypto
 		}
 	}
 
+	bool CBCEncryption::Encrypt (const uint8_t * in, std::size_t len, uint8_t * out)
+	{
+		div_t d = div (len, 16);
+		if (d.rem) return false; // len is not multipple of 16
+		Encrypt (d.quot, (const ChipherBlock *)in, (ChipherBlock *)out); 
+		return true;
+	}
+
 	void CBCDecryption::Decrypt (int numBlocks, const ChipherBlock * in, ChipherBlock * out)
 	{
 		for (int i = 0; i < numBlocks; i++)
 		{
+			ChipherBlock tmp = in[i];
 			m_ECBDecryption.ProcessData (out[i].buf, in[i].buf, 16);
 			out[i].ll[0] ^= m_IV.ll[0];
 			out[i].ll[1] ^= m_IV.ll[1];
-			m_IV = in[i];
+			m_IV = tmp;
 		}
 	}
+
+	bool CBCDecryption::Decrypt (const uint8_t * in, std::size_t len, uint8_t * out)
+	{
+		div_t d = div (len, 16);
+		if (d.rem) return false; // len is not multipple of 16
+		Decrypt (d.quot, (const ChipherBlock *)in, (ChipherBlock *)out); 
+		return true;
+	}
 }
 }
 
diff --git a/aes.h b/aes.h
index 3d71ebed..763b22eb 100644
--- a/aes.h
+++ b/aes.h
@@ -25,6 +25,7 @@ namespace crypto
 			void SetIV (uint8_t * iv) { memcpy (m_LastBlock.buf, iv, 16); }; // 16 bytes
 
 			void Encrypt (int numBlocks, const ChipherBlock * in, ChipherBlock * out);
+			bool Encrypt (const uint8_t * in, std::size_t len, uint8_t * out);
 
 		private:
 
@@ -42,6 +43,7 @@ namespace crypto
 			void SetIV (uint8_t * iv) { memcpy (m_IV.buf, iv, 16); }; // 16 bytes
 
 			void Decrypt (int numBlocks, const ChipherBlock * in, ChipherBlock * out);
+			bool Decrypt (const uint8_t * in, std::size_t len, uint8_t * out);
 
 		private: