Build updates

git-svn-id: https://mumble.svn.sourceforge.net/svnroot/mumble/trunk@685 05730e5d-ab1b-0410-a4ac-84af385074fa

1 files changed, 107 insertions, 0 deletions

diff --git a/src/CryptState.cpp b/src/CryptState.cpp
new file mode 100644
index 000000000..465826901
--- /dev/null
+++ b/src/CryptState.cpp
@@ -0,0 +1,107 @@
+/* Copyright (C) 2005-2007, Thorvald Natvig <thorvald@natvig.com>
+
+   All rights reserved.
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions
+   are met:
+
+   - Redistributions of source code must retain the above copyright notice,
+     this list of conditions and the following disclaimer.
+   - Redistributions in binary form must reproduce the above copyright notice,
+     this list of conditions and the following disclaimer in the documentation
+     and/or other materials provided with the distribution.
+   - Neither the name of the Mumble Developers nor the names of its
+     contributors may be used to endorse or promote products derived from this
+     software without specific prior written permission.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+   A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
+   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#include "CryptState.h"
+
+CryptState::CryptState() {
+	bInit = false;
+}
+
+bool CryptState::isValid() const {
+	return bInit;
+}
+
+void CryptState::genKey() {
+	RAND_bytes(raw_key, AES_BLOCK_SIZE);
+	RAND_bytes(encrypt_iv, AES_BLOCK_SIZE);
+	RAND_bytes(decrypt_iv, AES_BLOCK_SIZE);
+	AES_set_encrypt_key(raw_key, 128, &crypt_key);
+	bInit = true;
+}
+
+void CryptState::setKey(const unsigned char *rkey, const unsigned char *eiv, const unsigned char *div) {
+	memcpy(raw_key, rkey, AES_BLOCK_SIZE);
+	memcpy(encrypt_iv, eiv, AES_BLOCK_SIZE);
+	memcpy(decrypt_iv, div, AES_BLOCK_SIZE);
+	AES_set_encrypt_key(raw_key, 128, &crypt_key);
+	bInit = true;
+}
+
+void CryptState::setDecryptIV(const unsigned char *iv) {
+	memcpy(decrypt_iv, iv, AES_BLOCK_SIZE);
+}
+
+void CryptState::encrypt(const unsigned char *source, unsigned char *dst, unsigned int plain_length) {
+	unsigned int crypted_length = plain_length + 4;
+	
+	// First, increase our IV.
+	for(int i=0;i<AES_BLOCK_SIZE;i++)
+		if (++encrypt_iv[i])
+			break;
+	
+	dst[0] = encrypt_iv[0];
+	
+	// Checksum (cheeze it)
+	dst[1] = encrypt_iv[1];
+	dst[2] = encrypt_iv[2];
+	dst[3] = encrypt_iv[3];
+	memcpy(dst + 4, source, plain_length);
+}
+
+bool CryptState::decrypt(const unsigned char *source, unsigned char *dst, unsigned int crypted_length) {
+	if (crypted_length < 4)
+		return false;
+
+	unsigned int plain_length = crypted_length - 4;
+	
+	unsigned char saveiv[AES_BLOCK_SIZE];
+	unsigned char ivbyte = source[0];
+
+	memcpy(saveiv, decrypt_iv, AES_BLOCK_SIZE);
+
+	if (ivbyte > decrypt_iv[0]) {
+		decrypt_iv[0] = ivbyte;
+	} else if (ivbyte < decrypt_iv[0]) {
+		for(int i=1;i<AES_BLOCK_SIZE;i++)
+			if (++decrypt_iv[i])
+				break;
+		decrypt_iv[0] = ivbyte;
+	} else {
+		return false;
+	}
+	if (memcmp(source+1, & decrypt_iv[1], 3) != 0) {
+		memcpy(decrypt_iv, saveiv, AES_BLOCK_SIZE);
+		return false;
+	}
+	memcpy(dst, source + 4, plain_length);
+	tLastGood.restart();
+	return true;
+}
+