1 files changed, 58 insertions, 0 deletions
diff --git a/botan/src/kdf/mgf1/mgf1.cpp b/botan/src/kdf/mgf1/mgf1.cpp
new file mode 100644
index 0000000..a26e33a
--- /dev/null
+++ b/botan/src/kdf/mgf1/mgf1.cpp
@@ -0,0 +1,58 @@
+/*
+* MGF1
+* (C) 1999-2007 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#include <botan/mgf1.h>
+#include <botan/loadstor.h>
+#include <botan/exceptn.h>
+#include <botan/xor_buf.h>
+#include <algorithm>
+#include <memory>
+
+namespace Botan {
+
+/*
+* MGF1 Mask Generation Function
+*/
+void MGF1::mask(const byte in[], u32bit in_len, byte out[],
+                u32bit out_len) const
+   {
+   u32bit counter = 0;
+
+   while(out_len)
+      {
+      hash->update(in, in_len);
+      for(u32bit j = 0; j != 4; ++j)
+         hash->update(get_byte(j, counter));
+      SecureVector<byte> buffer = hash->final();
+
+      u32bit xored = std::min(buffer.size(), out_len);
+      xor_buf(out, buffer.begin(), xored);
+      out += xored;
+      out_len -= xored;
+
+      ++counter;
+      }
+   }
+
+/*
+* MGF1 Constructor
+*/
+MGF1::MGF1(HashFunction* h) : hash(h)
+   {
+   if(!hash)
+      throw Invalid_Argument("MGF1 given null hash object");
+   }
+
+/*
+* MGF1 Destructor
+*/
+MGF1::~MGF1()
+   {
+   delete hash;
+   }
+
+}