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authorlloyd <[email protected]>2008-09-28 19:29:24 +0000
committerlloyd <[email protected]>2008-09-28 19:29:24 +0000
commit9bcfe627321ddc81691b835dffaa6324ac4684a4 (patch)
treefe5e8ae9813b853549558b59833022e87e83981b /src/modes/cts/cts.cpp
parent9822a701516396b7de4e41339faecd48ff8dc8ff (diff)
Move all modules into src/ directory
Diffstat (limited to 'src/modes/cts/cts.cpp')
-rw-r--r--src/modes/cts/cts.cpp175
1 files changed, 175 insertions, 0 deletions
diff --git a/src/modes/cts/cts.cpp b/src/modes/cts/cts.cpp
new file mode 100644
index 000000000..8af775713
--- /dev/null
+++ b/src/modes/cts/cts.cpp
@@ -0,0 +1,175 @@
+/*************************************************
+* CTS Mode Source File *
+* (C) 1999-2007 Jack Lloyd *
+*************************************************/
+
+#include <botan/cts.h>
+#include <botan/lookup.h>
+#include <botan/xor_buf.h>
+#include <algorithm>
+
+namespace Botan {
+
+/*************************************************
+* CTS Encryption Constructor *
+*************************************************/
+CTS_Encryption::CTS_Encryption(const std::string& cipher_name) :
+ BlockCipherMode(cipher_name, "CTS", block_size_of(cipher_name), 0, 2)
+ {
+ }
+
+/*************************************************
+* CTS Encryption Constructor *
+*************************************************/
+CTS_Encryption::CTS_Encryption(const std::string& cipher_name,
+ const SymmetricKey& key,
+ const InitializationVector& iv) :
+ BlockCipherMode(cipher_name, "CTS", block_size_of(cipher_name), 0, 2)
+ {
+ set_key(key);
+ set_iv(iv);
+ }
+
+/*************************************************
+* Encrypt a block *
+*************************************************/
+void CTS_Encryption::encrypt(const byte block[])
+ {
+ xor_buf(state, block, BLOCK_SIZE);
+ cipher->encrypt(state);
+ send(state, BLOCK_SIZE);
+ }
+
+/*************************************************
+* Encrypt in CTS mode *
+*************************************************/
+void CTS_Encryption::write(const byte input[], u32bit length)
+ {
+ u32bit copied = std::min(BUFFER_SIZE - position, length);
+ buffer.copy(position, input, copied);
+ length -= copied;
+ input += copied;
+ position += copied;
+
+ if(length == 0) return;
+
+ encrypt(buffer);
+ if(length > BLOCK_SIZE)
+ {
+ encrypt(buffer + BLOCK_SIZE);
+ while(length > 2*BLOCK_SIZE)
+ {
+ encrypt(input);
+ length -= BLOCK_SIZE;
+ input += BLOCK_SIZE;
+ }
+ position = 0;
+ }
+ else
+ {
+ copy_mem(buffer.begin(), buffer + BLOCK_SIZE, BLOCK_SIZE);
+ position = BLOCK_SIZE;
+ }
+ buffer.copy(position, input, length);
+ position += length;
+ }
+
+/*************************************************
+* Finish encrypting in CTS mode *
+*************************************************/
+void CTS_Encryption::end_msg()
+ {
+ if(position < BLOCK_SIZE + 1)
+ throw Exception("CTS_Encryption: insufficient data to encrypt");
+ xor_buf(state, buffer, BLOCK_SIZE);
+ cipher->encrypt(state);
+ SecureVector<byte> cn = state;
+ clear_mem(buffer + position, BUFFER_SIZE - position);
+ encrypt(buffer + BLOCK_SIZE);
+ send(cn, position - BLOCK_SIZE);
+ }
+
+/*************************************************
+* CTS Decryption Constructor *
+*************************************************/
+CTS_Decryption::CTS_Decryption(const std::string& cipher_name) :
+ BlockCipherMode(cipher_name, "CTS", block_size_of(cipher_name), 0, 2)
+ {
+ temp.create(BLOCK_SIZE);
+ }
+
+/*************************************************
+* CTS Decryption Constructor *
+*************************************************/
+CTS_Decryption::CTS_Decryption(const std::string& cipher_name,
+ const SymmetricKey& key,
+ const InitializationVector& iv) :
+ BlockCipherMode(cipher_name, "CTS", block_size_of(cipher_name), 0, 2)
+ {
+ temp.create(BLOCK_SIZE);
+ set_key(key);
+ set_iv(iv);
+ }
+
+/*************************************************
+* Decrypt a block *
+*************************************************/
+void CTS_Decryption::decrypt(const byte block[])
+ {
+ cipher->decrypt(block, temp);
+ xor_buf(temp, state, BLOCK_SIZE);
+ send(temp, BLOCK_SIZE);
+ state.copy(block, BLOCK_SIZE);
+ }
+
+/*************************************************
+* Decrypt in CTS mode *
+*************************************************/
+void CTS_Decryption::write(const byte input[], u32bit length)
+ {
+ u32bit copied = std::min(BUFFER_SIZE - position, length);
+ buffer.copy(position, input, copied);
+ length -= copied;
+ input += copied;
+ position += copied;
+
+ if(length == 0) return;
+
+ decrypt(buffer);
+ if(length > BLOCK_SIZE)
+ {
+ decrypt(buffer + BLOCK_SIZE);
+ while(length > 2*BLOCK_SIZE)
+ {
+ decrypt(input);
+ length -= BLOCK_SIZE;
+ input += BLOCK_SIZE;
+ }
+ position = 0;
+ }
+ else
+ {
+ copy_mem(buffer.begin(), buffer + BLOCK_SIZE, BLOCK_SIZE);
+ position = BLOCK_SIZE;
+ }
+ buffer.copy(position, input, length);
+ position += length;
+ }
+
+/*************************************************
+* Finish decrypting in CTS mode *
+*************************************************/
+void CTS_Decryption::end_msg()
+ {
+ cipher->decrypt(buffer, temp);
+ xor_buf(temp, buffer + BLOCK_SIZE, position - BLOCK_SIZE);
+ SecureVector<byte> xn = temp;
+ copy_mem(buffer + position, xn + (position - BLOCK_SIZE),
+ BUFFER_SIZE - position);
+ cipher->decrypt(buffer + BLOCK_SIZE, temp);
+ xor_buf(temp, state, BLOCK_SIZE);
+ send(temp, BLOCK_SIZE);
+ send(xn, position - BLOCK_SIZE);
+ }
+
+}