Cipher_Mode API improvements

The Cipher_Mode::update API is more general than needed to just
support ciphers (this is due to it previously being an API of
Transform which before 8b85b780515 was Cipher_Mode's base class)

Define a less general interface `process` which either processes the
blocks in-place, producing exactly as much output as there was input,
or (SIV/CCM case) saves the entire message for processing in `finish`.
These two uses cover all current or anticipated cipher modes.

Leaves `update` for compatability with existing callers; all that is
needed is an inline function forwarding to `process`.

Removes the return type from `start` - in all cipher implementations,
this always returned an empty vector.

Adds BOTAN_ARG_CHECK macro; right now BOTAN_ASSERT is being used
for argument checking in some places, which is not right at all.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/lib/filters/cipher_filter.cpp b/src/lib/filters/cipher_filter.cpp
index f91cf3aa2..ed82880aa 100644
--- a/src/lib/filters/cipher_filter.cpp
+++ b/src/lib/filters/cipher_filter.cpp
@@ -85,7 +85,7 @@ void Cipher_Mode_Filter::end_msg()
 
 void Cipher_Mode_Filter::start_msg()
    {
-   send(m_mode->start(m_nonce.get()));
+   m_mode->start(m_nonce.get());
    }
 
 void Cipher_Mode_Filter::buffered_block(const byte input[], size_t input_length)