1 files changed, 52 insertions, 0 deletions
diff --git a/comm/third_party/botan/src/lib/rng/processor_rng/processor_rng.h b/comm/third_party/botan/src/lib/rng/processor_rng/processor_rng.h
new file mode 100644
index 0000000000..5900e386e0
--- /dev/null
+++ b/comm/third_party/botan/src/lib/rng/processor_rng/processor_rng.h
@@ -0,0 +1,52 @@
+/*
+* (C) 2016,2019,2020 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#ifndef BOTAN_RNG_PROCESSOR_RNG_H_
+#define BOTAN_RNG_PROCESSOR_RNG_H_
+
+#include <botan/rng.h>
+
+namespace Botan {
+
+/**
+* Directly invokes a CPU specific instruction to generate random numbers.
+* On x86, the RDRAND instruction is used.
+* on POWER, the DARN instruction is used.
+*/
+class BOTAN_PUBLIC_API(2,15) Processor_RNG final : public Hardware_RNG
+   {
+   public:
+      /**
+      * Constructor will throw if CPU does not have RDRAND bit set
+      */
+      Processor_RNG();
+
+      /**
+      * Return true if RNG instruction is available on the current processor
+      */
+      static bool available();
+
+      bool accepts_input() const override { return false; }
+      bool is_seeded() const override { return true; }
+
+      void randomize(uint8_t out[], size_t out_len) override;
+
+      /*
+      * No way to provide entropy to RDRAND generator, so add_entropy is ignored
+      */
+      void add_entropy(const uint8_t[], size_t) override;
+
+      /*
+      * No way to reseed processor provided generator, so reseed is ignored
+      */
+      size_t reseed(Entropy_Sources&, size_t, std::chrono::milliseconds) override;
+
+      std::string name() const override;
+   };
+
+}
+
+#endif