1 files changed, 31 insertions, 0 deletions
diff --git a/comm/third_party/botan/src/fuzzer/redc_p256.cpp b/comm/third_party/botan/src/fuzzer/redc_p256.cpp
new file mode 100644
index 0000000000..4c3809f089
--- /dev/null
+++ b/comm/third_party/botan/src/fuzzer/redc_p256.cpp
@@ -0,0 +1,31 @@
+/*
+* (C) 2015,2016 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include "fuzzers.h"
+#include <botan/reducer.h>
+#include <botan/curve_nistp.h>
+
+void fuzz(const uint8_t in[], size_t len)
+   {
+   if(len > 2*256/8)
+      return;
+
+   static const Botan::BigInt& prime = Botan::prime_p256();
+   static const Botan::BigInt prime_2 = prime * prime;
+   static Botan::Modular_Reducer prime_redc(prime);
+
+   Botan::BigInt input = Botan::BigInt::decode(in, len);
+
+   if(input < prime_2)
+      {
+      const Botan::BigInt ref = prime_redc.reduce(input);
+
+      Botan::secure_vector<Botan::word> ws;
+      Botan::redc_p256(input, ws);
+
+      FUZZER_ASSERT_EQUAL(ref, input);
+      }
+   }