Support seeking in Salsa20

Add a test that StreamCipher::seek throws if not keyed.

1 files changed, 1 insertions, 4 deletions

diff --git a/src/lib/stream/chacha/chacha.cpp b/src/lib/stream/chacha/chacha.cpp
index 52e5eaaf4..0f1e082cf 100644
--- a/src/lib/stream/chacha/chacha.cpp
+++ b/src/lib/stream/chacha/chacha.cpp
@@ -222,10 +222,7 @@ std::string ChaCha::name() const
 
 void ChaCha::seek(uint64_t offset)
    {
-   if (m_state.size() == 0 && m_buffer.size() == 0)
-      {
-      throw Invalid_State("You have to setup the stream cipher (key and iv)");
-      }
+   verify_key_set(m_state.empty() == false);
 
    // Find the block offset
    uint64_t counter = offset / 64;