Add HashFunction::copy_state

See GH #1037

2 files changed, 7 insertions, 0 deletions

diff --git a/src/lib/hash/blake2/blake2b.cpp b/src/lib/hash/blake2/blake2b.cpp
index b478af106..85171b16b 100644
--- a/src/lib/hash/blake2/blake2b.cpp
+++ b/src/lib/hash/blake2/blake2b.cpp
@@ -208,6 +208,11 @@ HashFunction* Blake2b::clone() const
    return new Blake2b(m_output_bits);
    }
 
+std::unique_ptr<HashFunction> Blake2b::copy_state() const
+   {
+   return std::unique_ptr<HashFunction>(new Blake2b(*this));
+   }
+
 void Blake2b::clear()
    {
    zeroise(m_H);
diff --git a/src/lib/hash/blake2/blake2b.h b/src/lib/hash/blake2/blake2b.h
index 473352174..c7ceac01e 100644
--- a/src/lib/hash/blake2/blake2b.h
+++ b/src/lib/hash/blake2/blake2b.h
@@ -38,6 +38,8 @@ class BOTAN_DLL Blake2b final : public HashFunction
       std::string name() const override;
       void clear() override;
 
+      std::unique_ptr<HashFunction> copy_state() const override;
+
    private:
       void add_data(const uint8_t input[], size_t length) override;
       void final_result(uint8_t out[]) override;