Eliminate the constant size_t values in SymmetricAlgorithm that give

the parameters of the key length. Instead define a new function which
returns a simple object which contains this information.

This definitely breaks backwards compatability, though only with code
that directly manipulates low level objects like BlockCipher*s
directly, which is probably relatively rare.

Also remove some deprecated accessor functions from lookup.h. It turns
out block_size_of and output_size_of are being used in the TLS code; I
need to remove them from there before I can delete these entirely.
Really that didn't make much sense, because they assumed all
implementations of a particular algorithm will have the same
specifications, which is definitely not necessarily true, especially
WRT key length. It is much safer (and probably simpler) to first
retrieve an instance of the actual object you are going to use and
then ask it directly.

1 files changed, 5 insertions, 0 deletions

diff --git a/src/mac/hmac/hmac.h b/src/mac/hmac/hmac.h
index 33af62f6a..505d0dd6b 100644
--- a/src/mac/hmac/hmac.h
+++ b/src/mac/hmac/hmac.h
@@ -23,6 +23,11 @@ class BOTAN_DLL HMAC : public MessageAuthenticationCode
       std::string name() const;
       MessageAuthenticationCode* clone() const;
 
+      Key_Length_Specification key_spec() const
+         {
+         return Key_Length_Specification(0, 2*hash->hash_block_size());
+         }
+
       /**
       * @param hash the hash to use for HMACing
       */