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-rw-r--r--old/botan/src/modes/cbc/cbc.cpp158
1 files changed, 158 insertions, 0 deletions
diff --git a/old/botan/src/modes/cbc/cbc.cpp b/old/botan/src/modes/cbc/cbc.cpp
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index 0000000..f26d4d6
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+++ b/old/botan/src/modes/cbc/cbc.cpp
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+/*
+* CBC Mode
+* (C) 1999-2007 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#include <botan/cbc.h>
+#include <botan/xor_buf.h>
+#include <algorithm>
+
+namespace Botan {
+
+/*
+* CBC Encryption Constructor
+*/
+CBC_Encryption::CBC_Encryption(BlockCipher* ciph,
+ BlockCipherModePaddingMethod* pad) :
+ BlockCipherMode(ciph, "CBC", ciph->BLOCK_SIZE),
+ padder(pad)
+ {
+ if(!padder->valid_blocksize(BLOCK_SIZE))
+ throw Invalid_Block_Size(name(), padder->name());
+ }
+
+/*
+* CBC Encryption Constructor
+*/
+CBC_Encryption::CBC_Encryption(BlockCipher* ciph,
+ BlockCipherModePaddingMethod* pad,
+ const SymmetricKey& key,
+ const InitializationVector& iv) :
+ BlockCipherMode(ciph, "CBC", ciph->BLOCK_SIZE),
+ padder(pad)
+ {
+ if(!padder->valid_blocksize(BLOCK_SIZE))
+ throw Invalid_Block_Size(name(), padder->name());
+ set_key(key);
+ set_iv(iv);
+ }
+
+/*
+* Encrypt in CBC mode
+*/
+void CBC_Encryption::write(const byte input[], u32bit length)
+ {
+ while(length)
+ {
+ u32bit xored = std::min(BLOCK_SIZE - position, length);
+ xor_buf(state + position, input, xored);
+ input += xored;
+ length -= xored;
+ position += xored;
+ if(position == BLOCK_SIZE)
+ {
+ cipher->encrypt(state);
+ send(state, BLOCK_SIZE);
+ position = 0;
+ }
+ }
+ }
+
+/*
+* Finish encrypting in CBC mode
+*/
+void CBC_Encryption::end_msg()
+ {
+ SecureVector<byte> padding(BLOCK_SIZE);
+ padder->pad(padding, padding.size(), position);
+ write(padding, padder->pad_bytes(BLOCK_SIZE, position));
+ if(position != 0)
+ throw Exception(name() + ": Did not pad to full blocksize");
+ }
+
+/*
+* Return a CBC mode name
+*/
+std::string CBC_Encryption::name() const
+ {
+ return (cipher->name() + "/" + mode_name + "/" + padder->name());
+ }
+
+/*
+* CBC Decryption Constructor
+*/
+CBC_Decryption::CBC_Decryption(BlockCipher* ciph,
+ BlockCipherModePaddingMethod* pad) :
+ BlockCipherMode(ciph, "CBC", ciph->BLOCK_SIZE),
+ padder(pad)
+ {
+ if(!padder->valid_blocksize(BLOCK_SIZE))
+ throw Invalid_Block_Size(name(), padder->name());
+ temp.create(BLOCK_SIZE);
+ }
+
+/*
+* CBC Decryption Constructor
+*/
+CBC_Decryption::CBC_Decryption(BlockCipher* ciph,
+ BlockCipherModePaddingMethod* pad,
+ const SymmetricKey& key,
+ const InitializationVector& iv) :
+ BlockCipherMode(ciph, "CBC", ciph->BLOCK_SIZE),
+ padder(pad)
+ {
+ if(!padder->valid_blocksize(BLOCK_SIZE))
+ throw Invalid_Block_Size(name(), padder->name());
+ temp.create(BLOCK_SIZE);
+ set_key(key);
+ set_iv(iv);
+ }
+
+/*
+* Decrypt in CBC mode
+*/
+void CBC_Decryption::write(const byte input[], u32bit length)
+ {
+ while(length)
+ {
+ if(position == BLOCK_SIZE)
+ {
+ cipher->decrypt(buffer, temp);
+ xor_buf(temp, state, BLOCK_SIZE);
+ send(temp, BLOCK_SIZE);
+ state = buffer;
+ position = 0;
+ }
+ u32bit added = std::min(BLOCK_SIZE - position, length);
+ buffer.copy(position, input, added);
+ input += added;
+ length -= added;
+ position += added;
+ }
+ }
+
+/*
+* Finish decrypting in CBC mode
+*/
+void CBC_Decryption::end_msg()
+ {
+ if(position != BLOCK_SIZE)
+ throw Decoding_Error(name());
+ cipher->decrypt(buffer, temp);
+ xor_buf(temp, state, BLOCK_SIZE);
+ send(temp, padder->unpad(temp, BLOCK_SIZE));
+ state = buffer;
+ position = 0;
+ }
+
+/*
+* Return a CBC mode name
+*/
+std::string CBC_Decryption::name() const
+ {
+ return (cipher->name() + "/" + mode_name + "/" + padder->name());
+ }
+
+}