For block and stream ciphers, don't set the size of the key vectors

until we are actually setting a key. This avoids the problem of
prototype objects consuming not just memory but the precious few bytes
of mlock'able memory that we're given by Linux.

Use clear_mem instead of a loop in BigInt::mask_bits

If OS2ECP encounters an invalid format type, include what type it was
in the exception message.

1 files changed, 3 insertions, 4 deletions

diff --git a/src/block/rc5/rc5.h b/src/block/rc5/rc5.h
index bf059a996..2279260a3 100644
--- a/src/block/rc5/rc5.h
+++ b/src/block/rc5/rc5.h
@@ -21,9 +21,9 @@ class BOTAN_DLL RC5 : public Block_Cipher_Fixed_Params<8, 1, 32>
       void encrypt_n(const byte in[], byte out[], size_t blocks) const;
       void decrypt_n(const byte in[], byte out[], size_t blocks) const;
 
-      void clear() { zeroise(S); }
+      void clear() { S.clear(); }
       std::string name() const;
-      BlockCipher* clone() const { return new RC5(get_rounds()); }
+      BlockCipher* clone() const { return new RC5(rounds); }
 
       /**
       * @param rounds the number of RC5 rounds to run. Must be between
@@ -31,10 +31,9 @@ class BOTAN_DLL RC5 : public Block_Cipher_Fixed_Params<8, 1, 32>
       */
       RC5(size_t rounds);
    private:
-      size_t get_rounds() const { return (S.size() - 2) / 2; }
-
       void key_schedule(const byte[], size_t);
 
+      size_t rounds;
       secure_vector<u32bit> S;
    };