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-rw-r--r--src/modes/cbc/cbc.cpp299
1 files changed, 0 insertions, 299 deletions
diff --git a/src/modes/cbc/cbc.cpp b/src/modes/cbc/cbc.cpp
deleted file mode 100644
index 31834bade..000000000
--- a/src/modes/cbc/cbc.cpp
+++ /dev/null
@@ -1,299 +0,0 @@
-/*
-* CBC Mode
-* (C) 1999-2007,2013 Jack Lloyd
-*
-* Distributed under the terms of the Botan license
-*/
-
-#include <botan/cbc.h>
-#include <botan/loadstor.h>
-#include <botan/internal/xor_buf.h>
-#include <botan/internal/rounding.h>
-
-namespace Botan {
-
-CBC_Mode::CBC_Mode(BlockCipher* cipher, BlockCipherModePaddingMethod* padding) :
- m_cipher(cipher),
- m_padding(padding),
- m_state(m_cipher->block_size())
- {
- if(m_padding && !m_padding->valid_blocksize(cipher->block_size()))
- throw std::invalid_argument("Padding " + m_padding->name() +
- " cannot be used with " +
- cipher->name() + "/CBC");
- }
-
-void CBC_Mode::clear()
- {
- m_cipher->clear();
- m_state.clear();
- }
-
-std::string CBC_Mode::name() const
- {
- if(m_padding)
- return cipher().name() + "/CBC/" + padding().name();
- else
- return cipher().name() + "/CBC/CTS";
- }
-
-size_t CBC_Mode::update_granularity() const
- {
- return cipher().parallel_bytes();
- }
-
-Key_Length_Specification CBC_Mode::key_spec() const
- {
- return cipher().key_spec();
- }
-
-size_t CBC_Mode::default_nonce_length() const
- {
- return cipher().block_size();
- }
-
-bool CBC_Mode::valid_nonce_length(size_t n) const
- {
- return (n == 0 || n == cipher().block_size());
- }
-
-void CBC_Mode::key_schedule(const byte key[], size_t length)
- {
- m_cipher->set_key(key, length);
- }
-
-secure_vector<byte> CBC_Mode::start(const byte nonce[], size_t nonce_len)
- {
- if(!valid_nonce_length(nonce_len))
- throw Invalid_IV_Length(name(), nonce_len);
-
- /*
- * A nonce of zero length means carry the last ciphertext value over
- * as the new IV, as unfortunately some protocols require this. If
- * this is the first message then we use an IV of all zeros.
- */
- if(nonce_len)
- m_state.assign(nonce, nonce + nonce_len);
-
- return secure_vector<byte>();
- }
-
-size_t CBC_Encryption::minimum_final_size() const
- {
- return 0;
- }
-
-size_t CBC_Encryption::output_length(size_t input_length) const
- {
- return round_up(input_length, cipher().block_size());
- }
-
-void CBC_Encryption::update(secure_vector<byte>& buffer, size_t offset)
- {
- BOTAN_ASSERT(buffer.size() >= offset, "Offset is sane");
- const size_t sz = buffer.size() - offset;
- byte* buf = &buffer[offset];
-
- const size_t BS = cipher().block_size();
-
- BOTAN_ASSERT(sz % BS == 0, "CBC input is full blocks");
- const size_t blocks = sz / BS;
-
- if(blocks)
- {
- xor_buf(&buf[0], state_ptr(), BS);
- cipher().encrypt(&buf[0]);
-
- for(size_t i = 1; i != blocks; ++i)
- {
- xor_buf(&buf[BS*i], &buf[BS*(i-1)], BS);
- cipher().encrypt(&buf[BS*i]);
- }
-
- state().assign(&buf[BS*(blocks-1)], &buf[BS*blocks]);
- }
- }
-
-void CBC_Encryption::finish(secure_vector<byte>& buffer, size_t offset)
- {
- BOTAN_ASSERT(buffer.size() >= offset, "Offset is sane");
-
- const size_t BS = cipher().block_size();
-
- const size_t bytes_in_final_block = (buffer.size()-offset) % BS;
-
- padding().add_padding(buffer, bytes_in_final_block, BS);
-
- if((buffer.size()-offset) % BS)
- throw std::runtime_error("Did not pad to full block size in " + name());
-
- update(buffer, offset);
- }
-
-bool CTS_Encryption::valid_nonce_length(size_t n) const
- {
- return (n == cipher().block_size());
- }
-
-size_t CTS_Encryption::minimum_final_size() const
- {
- return cipher().block_size() + 1;
- }
-
-size_t CTS_Encryption::output_length(size_t input_length) const
- {
- return input_length; // no ciphertext expansion in CTS
- }
-
-void CTS_Encryption::finish(secure_vector<byte>& buffer, size_t offset)
- {
- BOTAN_ASSERT(buffer.size() >= offset, "Offset is sane");
- byte* buf = &buffer[offset];
- const size_t sz = buffer.size() - offset;
-
- const size_t BS = cipher().block_size();
-
- if(sz < BS + 1)
- throw Encoding_Error(name() + ": insufficient data to encrypt");
-
- if(sz % BS == 0)
- {
- update(buffer, offset);
-
- // swap last two blocks
- for(size_t i = 0; i != BS; ++i)
- std::swap(buffer[buffer.size()-BS+i], buffer[buffer.size()-2*BS+i]);
- }
- else
- {
- const size_t full_blocks = ((sz / BS) - 1) * BS;
- const size_t final_bytes = sz - full_blocks;
- BOTAN_ASSERT(final_bytes > BS && final_bytes < 2*BS, "Left over size in expected range");
-
- secure_vector<byte> last(buf + full_blocks, buf + full_blocks + final_bytes);
- buffer.resize(full_blocks + offset);
- update(buffer, offset);
-
- xor_buf(&last[0], state_ptr(), BS);
- cipher().encrypt(&last[0]);
-
- for(size_t i = 0; i != final_bytes - BS; ++i)
- {
- std::swap(last[i], last[i + BS]);
- last[i] ^= last[i + BS];
- }
-
- cipher().encrypt(&last[0]);
-
- buffer += last;
- }
- }
-
-size_t CBC_Decryption::output_length(size_t input_length) const
- {
- return input_length; // precise for CTS, worst case otherwise
- }
-
-size_t CBC_Decryption::minimum_final_size() const
- {
- return cipher().block_size();
- }
-
-void CBC_Decryption::update(secure_vector<byte>& buffer, size_t offset)
- {
- BOTAN_ASSERT(buffer.size() >= offset, "Offset is sane");
- const size_t sz = buffer.size() - offset;
- byte* buf = &buffer[offset];
-
- const size_t BS = cipher().block_size();
-
- BOTAN_ASSERT(sz % BS == 0, "Input is full blocks");
- size_t blocks = sz / BS;
-
- while(blocks)
- {
- const size_t to_proc = std::min(BS * blocks, m_tempbuf.size());
-
- cipher().decrypt_n(buf, &m_tempbuf[0], to_proc / BS);
-
- xor_buf(&m_tempbuf[0], state_ptr(), BS);
- xor_buf(&m_tempbuf[BS], buf, to_proc - BS);
- copy_mem(state_ptr(), buf + (to_proc - BS), BS);
-
- copy_mem(buf, &m_tempbuf[0], to_proc);
-
- buf += to_proc;
- blocks -= to_proc / BS;
- }
- }
-
-void CBC_Decryption::finish(secure_vector<byte>& buffer, size_t offset)
- {
- BOTAN_ASSERT(buffer.size() >= offset, "Offset is sane");
- const size_t sz = buffer.size() - offset;
-
- const size_t BS = cipher().block_size();
-
- if(sz == 0 || sz % BS)
- throw Decoding_Error(name() + ": Ciphertext not a multiple of block size");
-
- update(buffer, offset);
-
- const size_t pad_bytes = BS - padding().unpad(&buffer[buffer.size()-BS], BS);
- buffer.resize(buffer.size() - pad_bytes); // remove padding
- }
-
-bool CTS_Decryption::valid_nonce_length(size_t n) const
- {
- return (n == cipher().block_size());
- }
-
-size_t CTS_Decryption::minimum_final_size() const
- {
- return cipher().block_size() + 1;
- }
-
-void CTS_Decryption::finish(secure_vector<byte>& buffer, size_t offset)
- {
- BOTAN_ASSERT(buffer.size() >= offset, "Offset is sane");
- const size_t sz = buffer.size() - offset;
- byte* buf = &buffer[offset];
-
- const size_t BS = cipher().block_size();
-
- if(sz < BS + 1)
- throw Encoding_Error(name() + ": insufficient data to decrypt");
-
- if(sz % BS == 0)
- {
- // swap last two blocks
- for(size_t i = 0; i != BS; ++i)
- std::swap(buffer[buffer.size()-BS+i], buffer[buffer.size()-2*BS+i]);
-
- update(buffer, offset);
- }
- else
- {
- const size_t full_blocks = ((sz / BS) - 1) * BS;
- const size_t final_bytes = sz - full_blocks;
- BOTAN_ASSERT(final_bytes > BS && final_bytes < 2*BS, "Left over size in expected range");
-
- secure_vector<byte> last(buf + full_blocks, buf + full_blocks + final_bytes);
- buffer.resize(full_blocks + offset);
- update(buffer, offset);
-
- cipher().decrypt(&last[0]);
- xor_buf(&last[0], &last[BS], final_bytes - BS);
-
- for(size_t i = 0; i != final_bytes - BS; ++i)
- std::swap(last[i], last[i + BS]);
-
- cipher().decrypt(&last[0]);
- xor_buf(&last[0], state_ptr(), BS);
-
- buffer += last;
- }
-
- }
-
-}
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