Add RandomNumberGenerator::accepts_input

1 files changed, 29 insertions, 12 deletions

diff --git a/src/lib/rng/rng.cpp b/src/lib/rng/rng.cpp
index 2cf3b7b81..2947ac629 100644
--- a/src/lib/rng/rng.cpp
+++ b/src/lib/rng/rng.cpp
@@ -17,15 +17,22 @@ namespace Botan {
 
 void RandomNumberGenerator::randomize_with_ts_input(uint8_t output[], size_t output_len)
    {
-   /*
-   Form additional input which is provided to the PRNG implementation
-   to paramaterize the KDF output.
-   */
-   uint8_t additional_input[16] = { 0 };
-   store_le(OS::get_system_timestamp_ns(), additional_input);
-   store_le(OS::get_high_resolution_clock(), additional_input + 8);
+   if(this->accepts_input())
+      {
+      /*
+      Form additional input which is provided to the PRNG implementation
+      to paramaterize the KDF output.
+      */
+      uint8_t additional_input[16] = { 0 };
+      store_le(OS::get_system_timestamp_ns(), additional_input);
+      store_le(OS::get_high_resolution_clock(), additional_input + 8);
 
-   randomize_with_input(output, output_len, additional_input, sizeof(additional_input));
+      this->randomize_with_input(output, output_len, additional_input, sizeof(additional_input));
+      }
+   else
+      {
+      this->randomize(output, output_len);
+      }
    }
 
 void RandomNumberGenerator::randomize_with_input(uint8_t output[], size_t output_len,
@@ -39,14 +46,24 @@ size_t RandomNumberGenerator::reseed(Entropy_Sources& srcs,
                                      size_t poll_bits,
                                      std::chrono::milliseconds poll_timeout)
    {
-   return srcs.poll(*this, poll_bits, poll_timeout);
+   if(this->accepts_input())
+      {
+      return srcs.poll(*this, poll_bits, poll_timeout);
+      }
+   else
+      {
+      return 0;
+      }
    }
 
 void RandomNumberGenerator::reseed_from_rng(RandomNumberGenerator& rng, size_t poll_bits)
    {
-   secure_vector<uint8_t> buf(poll_bits / 8);
-   rng.randomize(buf.data(), buf.size());
-   this->add_entropy(buf.data(), buf.size());
+   if(this->accepts_input())
+      {
+      secure_vector<uint8_t> buf(poll_bits / 8);
+      rng.randomize(buf.data(), buf.size());
+      this->add_entropy(buf.data(), buf.size());
+      }
    }
 
 RandomNumberGenerator* RandomNumberGenerator::make_rng()