1 files changed, 41 insertions, 0 deletions
diff --git a/botan/src/kdf/kdf2/kdf2.cpp b/botan/src/kdf/kdf2/kdf2.cpp
new file mode 100644
index 0000000..167f644
--- /dev/null
+++ b/botan/src/kdf/kdf2/kdf2.cpp
@@ -0,0 +1,41 @@
+/*
+* KDF2
+* (C) 1999-2007 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#include <botan/kdf2.h>
+#include <botan/loadstor.h>
+
+namespace Botan {
+
+/*
+* KDF2 Key Derivation Mechanism
+*/
+SecureVector<byte> KDF2::derive(u32bit out_len,
+                                const byte secret[], u32bit secret_len,
+                                const byte P[], u32bit P_len) const
+   {
+   SecureVector<byte> output;
+   u32bit counter = 1;
+
+   while(out_len && counter)
+      {
+      hash->update(secret, secret_len);
+      for(u32bit j = 0; j != 4; ++j)
+         hash->update(get_byte(j, counter));
+      hash->update(P, P_len);
+      SecureVector<byte> hash_result = hash->final();
+
+      u32bit added = std::min(hash_result.size(), out_len);
+      output.append(hash_result, added);
+      out_len -= added;
+
+      ++counter;
+      }
+
+   return output;
+   }
+
+}