Add T::provider() to allow user to inquire about implementation used

For block ciphers, stream ciphers, hashes, MACs, and cipher modes.
Cipher_Mode already had it, with a slightly different usage.

2 files changed, 13 insertions, 0 deletions

diff --git a/src/lib/block/threefish/threefish.cpp b/src/lib/block/threefish/threefish.cpp
index 33b3e25c8..4ba834c94 100644
--- a/src/lib/block/threefish/threefish.cpp
+++ b/src/lib/block/threefish/threefish.cpp
@@ -98,6 +98,18 @@ void Threefish_512::skein_feedfwd(const secure_vector<u64bit>& M,
             m_K[4] ^ m_K[5] ^ m_K[6] ^ m_K[7] ^ 0x1BD11BDAA9FC1A22;
    }
 
+const char* Threefish_512::provider() const
+   {
+#if defined(BOTAN_HAS_THREEFISH_512_AVX2)
+   if(CPUID::has_avx2())
+      {
+      return "avx2";
+      }
+#endif
+
+   return "base";
+   }
+
 void Threefish_512::encrypt_n(const byte in[], byte out[], size_t blocks) const
    {
    BOTAN_ASSERT(m_K.size() == 9, "Key was set");
diff --git a/src/lib/block/threefish/threefish.h b/src/lib/block/threefish/threefish.h
index 270e71354..230c742f3 100644
--- a/src/lib/block/threefish/threefish.h
+++ b/src/lib/block/threefish/threefish.h
@@ -24,6 +24,7 @@ class BOTAN_DLL Threefish_512 final : public Block_Cipher_Fixed_Params<64, 64>
       void set_tweak(const byte tweak[], size_t len);
 
       void clear() override;
+      const char* provider() const override;
       std::string name() const override { return "Threefish-512"; }
       BlockCipher* clone() const override { return new Threefish_512; }
    protected: