aboutsummaryrefslogtreecommitdiffstats
path: root/src/modes/cbc
diff options
context:
space:
mode:
Diffstat (limited to 'src/modes/cbc')
-rw-r--r--src/modes/cbc/cbc.cpp157
-rw-r--r--src/modes/cbc/cbc.h49
-rw-r--r--src/modes/cbc/modinfo.txt10
3 files changed, 216 insertions, 0 deletions
diff --git a/src/modes/cbc/cbc.cpp b/src/modes/cbc/cbc.cpp
new file mode 100644
index 000000000..9ad598bed
--- /dev/null
+++ b/src/modes/cbc/cbc.cpp
@@ -0,0 +1,157 @@
+/*************************************************
+* CBC Mode Source File *
+* (C) 1999-2007 Jack Lloyd *
+*************************************************/
+
+#include <botan/cbc.h>
+#include <botan/lookup.h>
+#include <botan/xor_buf.h>
+#include <algorithm>
+
+namespace Botan {
+
+/*************************************************
+* CBC Encryption Constructor *
+*************************************************/
+CBC_Encryption::CBC_Encryption(const std::string& cipher_name,
+ const std::string& padding_name) :
+ BlockCipherMode(cipher_name, "CBC", block_size_of(cipher_name)),
+ padder(get_bc_pad(padding_name))
+ {
+ if(!padder->valid_blocksize(BLOCK_SIZE))
+ throw Invalid_Block_Size(name(), padder->name());
+ }
+
+/*************************************************
+* CBC Encryption Constructor *
+*************************************************/
+CBC_Encryption::CBC_Encryption(const std::string& cipher_name,
+ const std::string& padding_name,
+ const SymmetricKey& key,
+ const InitializationVector& iv) :
+ BlockCipherMode(cipher_name, "CBC", block_size_of(cipher_name)),
+ padder(get_bc_pad(padding_name))
+ {
+ 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(const std::string& cipher_name,
+ const std::string& padding_name) :
+ BlockCipherMode(cipher_name, "CBC", block_size_of(cipher_name)),
+ padder(get_bc_pad(padding_name))
+ {
+ if(!padder->valid_blocksize(BLOCK_SIZE))
+ throw Invalid_Block_Size(name(), padder->name());
+ temp.create(BLOCK_SIZE);
+ }
+
+/*************************************************
+* CBC Decryption Constructor *
+*************************************************/
+CBC_Decryption::CBC_Decryption(const std::string& cipher_name,
+ const std::string& padding_name,
+ const SymmetricKey& key,
+ const InitializationVector& iv) :
+ BlockCipherMode(cipher_name, "CBC", block_size_of(cipher_name)),
+ padder(get_bc_pad(padding_name))
+ {
+ 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());
+ }
+
+}
diff --git a/src/modes/cbc/cbc.h b/src/modes/cbc/cbc.h
new file mode 100644
index 000000000..a0a30f90f
--- /dev/null
+++ b/src/modes/cbc/cbc.h
@@ -0,0 +1,49 @@
+/*************************************************
+* CBC Mode Header File *
+* (C) 1999-2007 Jack Lloyd *
+*************************************************/
+
+#ifndef BOTAN_CBC_H__
+#define BOTAN_CBC_H__
+
+#include <botan/modebase.h>
+#include <botan/mode_pad.h>
+
+namespace Botan {
+
+/*************************************************
+* CBC Encryption *
+*************************************************/
+class BOTAN_DLL CBC_Encryption : public BlockCipherMode
+ {
+ public:
+ CBC_Encryption(const std::string&, const std::string&);
+ CBC_Encryption(const std::string&, const std::string&,
+ const SymmetricKey&, const InitializationVector&);
+ private:
+ std::string name() const;
+ void write(const byte[], u32bit);
+ void end_msg();
+ const BlockCipherModePaddingMethod* padder;
+ };
+
+/*************************************************
+* CBC Decryption *
+*************************************************/
+class BOTAN_DLL CBC_Decryption : public BlockCipherMode
+ {
+ public:
+ CBC_Decryption(const std::string&, const std::string&);
+ CBC_Decryption(const std::string&, const std::string&,
+ const SymmetricKey&, const InitializationVector&);
+ private:
+ std::string name() const;
+ void write(const byte[], u32bit);
+ void end_msg();
+ const BlockCipherModePaddingMethod* padder;
+ SecureVector<byte> temp;
+ };
+
+}
+
+#endif
diff --git a/src/modes/cbc/modinfo.txt b/src/modes/cbc/modinfo.txt
new file mode 100644
index 000000000..4ebc7730a
--- /dev/null
+++ b/src/modes/cbc/modinfo.txt
@@ -0,0 +1,10 @@
+realname "CBC block cipher mode"
+
+define CBC
+
+load_on auto
+
+<add>
+cbc.cpp
+cbc.h
+</add>
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-27 05:46:43 +0000