Refactor option parsing in cli and test code

Allows cleaning up header includes, also somewhat smaller binaries.

1 files changed, 89 insertions, 0 deletions

diff --git a/src/cli/cli_rng.cpp b/src/cli/cli_rng.cpp
new file mode 100644
index 000000000..1e3ecb141
--- /dev/null
+++ b/src/cli/cli_rng.cpp
@@ -0,0 +1,89 @@
+/*
+* (C) 2015,2017 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include "cli.h"
+#include <botan/rng.h>
+#include <botan/entropy_src.h>
+#include <botan/cpuid.h>
+#include <botan/hex.h>
+
+#if defined(BOTAN_HAS_AUTO_SEEDING_RNG)
+   #include <botan/auto_rng.h>
+#endif
+
+#if defined(BOTAN_HAS_SYSTEM_RNG)
+   #include <botan/system_rng.h>
+#endif
+
+#if defined(BOTAN_HAS_RDRAND_RNG)
+   #include <botan/rdrand_rng.h>
+#endif
+
+#if defined(BOTAN_HAS_HMAC_DRBG)
+   #include <botan/hmac_drbg.h>
+#endif
+
+namespace Botan_CLI {
+
+std::unique_ptr<Botan::RandomNumberGenerator>
+cli_make_rng(const std::string& rng_type, const std::string& hex_drbg_seed)
+   {
+#if defined(BOTAN_HAS_SYSTEM_RNG)
+   if(rng_type == "system" || rng_type.empty())
+      {
+      return std::unique_ptr<Botan::RandomNumberGenerator>(new Botan::System_RNG);
+      }
+#endif
+
+#if defined(BOTAN_HAS_RDRAND_RNG)
+   if(rng_type == "rdrand")
+      {
+      if(Botan::CPUID::has_rdrand())
+         return std::unique_ptr<Botan::RandomNumberGenerator>(new Botan::RDRAND_RNG);
+      else
+         throw CLI_Error("RDRAND instruction not supported on this processor");
+      }
+#endif
+
+   const std::vector<uint8_t> drbg_seed = Botan::hex_decode(hex_drbg_seed);
+
+#if defined(BOTAN_HAS_AUTO_SEEDING_RNG)
+   if(rng_type == "auto" || rng_type == "entropy" || rng_type.empty())
+      {
+      std::unique_ptr<Botan::RandomNumberGenerator> rng;
+
+      if(rng_type == "entropy")
+         rng.reset(new Botan::AutoSeeded_RNG(Botan::Entropy_Sources::global_sources()));
+      else
+         rng.reset(new Botan::AutoSeeded_RNG);
+
+      if(drbg_seed.size() > 0)
+         rng->add_entropy(drbg_seed.data(), drbg_seed.size());
+      return rng;
+      }
+#endif
+
+#if defined(BOTAN_HAS_HMAC_DRBG) && defined(BOTAN_AUTO_RNG_HMAC)
+   if(rng_type == "drbg")
+      {
+      std::unique_ptr<Botan::MessageAuthenticationCode> mac =
+         Botan::MessageAuthenticationCode::create(BOTAN_AUTO_RNG_HMAC);
+      std::unique_ptr<Botan::Stateful_RNG> rng(new Botan::HMAC_DRBG(std::move(mac)));
+      rng->add_entropy(drbg_seed.data(), drbg_seed.size());
+
+      if(rng->is_seeded() == false)
+         throw CLI_Error("For " + rng->name() + " a seed of at least " +
+                         std::to_string(rng->security_level()/8) +
+                         " bytes must be provided");
+
+      return std::unique_ptr<Botan::RandomNumberGenerator>(rng.release());
+      }
+#endif
+
+   throw CLI_Error_Unsupported("RNG", rng_type);
+   }
+
+}