1 files changed, 57 insertions, 0 deletions
diff --git a/comm/third_party/botan/src/lib/pubkey/mce/code_based_util.h b/comm/third_party/botan/src/lib/pubkey/mce/code_based_util.h
new file mode 100644
index 0000000000..5b0a9195a0
--- /dev/null
+++ b/comm/third_party/botan/src/lib/pubkey/mce/code_based_util.h
@@ -0,0 +1,57 @@
+/*
+ * (C) Copyright Projet SECRET, INRIA, Rocquencourt
+ * (C) Bhaskar Biswas and  Nicolas Sendrier
+ *
+ * (C) 2014 cryptosource GmbH
+ * (C) 2014 Falko Strenzke fstrenzke@cryptosource.de
+ *
+ * Botan is released under the Simplified BSD License (see license.txt)
+ *
+ */
+
+#ifndef BOTAN_CODE_BASED_UTIL_H_
+#define BOTAN_CODE_BASED_UTIL_H_
+
+#include <botan/gf2m_small_m.h>
+
+namespace Botan {
+
+/**
+* Expand an input to a bit mask depending on it being being zero or non-zero
+* @param tst the input
+* @return the mask 0xFFFF if tst is non-zero and 0 otherwise
+*/
+template<typename T>
+uint16_t expand_mask_16bit(T tst)
+   {
+   const uint16_t result = (tst != 0);
+   return ~(result - 1);
+   }
+
+inline gf2m gray_to_lex(gf2m gray)
+   {
+   gf2m result = gray ^ (gray >> 8);
+   result ^= (result >> 4);
+   result ^= (result >> 2);
+   result ^= (result >> 1);
+   return result;
+   }
+
+inline gf2m lex_to_gray(gf2m lex)
+   {
+   return (lex >> 1) ^ lex;
+   }
+
+inline size_t bit_size_to_byte_size(size_t bit_size)
+   {
+   return (bit_size - 1) / 8 + 1;
+   }
+
+inline size_t bit_size_to_32bit_size(size_t bit_size)
+   {
+   return (bit_size - 1) / 32 + 1;
+   }
+
+}
+
+#endif