make sure kdf labels are always used

1 files changed, 2 insertions, 1 deletions

diff --git a/src/lib/kdf/kdf2/kdf2.cpp b/src/lib/kdf/kdf2/kdf2.cpp
index 32bf678f7..760ebfc83 100644
--- a/src/lib/kdf/kdf2/kdf2.cpp
+++ b/src/lib/kdf/kdf2/kdf2.cpp
@@ -12,7 +12,7 @@ namespace Botan {
 size_t KDF2::kdf(byte key[], size_t key_len,
                  const byte secret[], size_t secret_len,
                  const byte salt[], size_t salt_len,
-                 const byte[], size_t) const
+                 const byte label[], size_t label_len) const
    {
    u32bit counter = 1;
    secure_vector<byte> h;
@@ -22,6 +22,7 @@ size_t KDF2::kdf(byte key[], size_t key_len,
       {
       m_hash->update(secret, secret_len);
       m_hash->update_be(counter++);
+      m_hash->update(label, label_len);
       m_hash->update(salt, salt_len);
       m_hash->final(h);