Add hacks for predictable random number and timestamp generation.

4 files changed, 46 insertions, 2 deletions

diff --git a/src/KM_prng.cpp b/src/KM_prng.cpp
index f9ec0c0..872bc48 100755
--- a/src/KM_prng.cpp
+++ b/src/KM_prng.cpp
@@ -36,6 +36,7 @@ THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <KM_mutex.h>
 #include <string.h>
 #include <assert.h>
+#include <boost/random.hpp>
 
 #ifdef HAVE_OPENSSL
 # define ENABLE_FIPS_186
@@ -69,8 +70,11 @@ namespace{
       AES_ctx   m_Context;
       byte_t    m_ctr_buf[RNG_BLOCK_SIZE];
       Mutex     m_Lock;
+      boost::random::mt19937 _test_rng;
+      boost::random::uniform_int_distribution<> _test_dist;
 
       h__RNG()
+	: _test_dist(0, 255)
       {
         memset(m_ctr_buf, 0, RNG_BLOCK_SIZE);
         byte_t rng_key[RNG_KEY_SIZE];
@@ -102,6 +106,7 @@ namespace{
         } // end AutoMutex context
 
         set_key(rng_key);
+	reset();
       }
         
       //
@@ -145,7 +150,19 @@ namespace{
         AES_encrypt(&m_Context, tmp);
         memcpy(buf + gen_count, tmp, len - gen_count);
           }
+
+	if (dcpomatic_test)
+	  {
+	    for (unsigned int i = 0; i < len; ++i)
+	      buf[i] = _test_dist(_test_rng);
+	  }
       }
+
+      void reset()
+        {
+	  _test_rng.seed(1);
+	  _test_dist.reset();
+	}
     };
 }
 
@@ -201,6 +218,12 @@ Kumu::FortunaRNG::FillRandom(Kumu::ByteString& Buffer)
 }
 
 
+void
+Kumu::FortunaRNG::Reset()
+{
+  s_RNG->reset();
+}
+
 //------------------------------------------------------------------------------------------
 
 #ifdef ENABLE_FIPS_186
diff --git a/src/KM_prng.h b/src/KM_prng.h
index 172af2b..f4497ed 100755
--- a/src/KM_prng.h
+++ b/src/KM_prng.h
@@ -45,6 +45,7 @@ namespace Kumu
       ~FortunaRNG();
       const byte_t* FillRandom(byte_t* buf, ui32_t len);
       const byte_t* FillRandom(ByteString&);
+      void Reset();
     };
 
 
diff --git a/src/KM_util.cpp b/src/KM_util.cpp
index 4c59c78..804abcb 100755
--- a/src/KM_util.cpp
+++ b/src/KM_util.cpp
@@ -40,6 +40,8 @@ THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <map>
 #include <string>
 
+bool Kumu::dcpomatic_test = false;
+
 const char*
 Kumu::Version()
 {
@@ -593,6 +595,13 @@ Kumu::GenRandomValue(UUID& ID)
   ID.Set(tmp_buf);
 }
 
+void
+Kumu::ResetTestRNG()
+{
+  FortunaRNG RNG;
+  RNG.Reset();
+}
+
 //
 void
 Kumu::GenRandomUUID(byte_t* buf)
@@ -749,7 +758,14 @@ Kumu::write_BER(byte_t* buf, ui64_t val, ui32_t ber_len)
 
 //
 Kumu::Timestamp::Timestamp() : m_TZOffsetMinutes(0) {
-  m_Timestamp.now();
+  if (dcpomatic_test)
+    {
+      m_Timestamp.x = 42;
+    }
+  else
+    {
+      m_Timestamp.now();
+    }
 }
 
 Kumu::Timestamp::Timestamp(const Timestamp& rhs) {
diff --git a/src/KM_util.h b/src/KM_util.h
index 9dcf846..a6b2de7 100755
--- a/src/KM_util.h
+++ b/src/KM_util.h
@@ -40,6 +40,8 @@ THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 namespace Kumu
 {
+  extern bool dcpomatic_test;
+
   // The version number declaration and explanation are in ../configure.ac
   const char* Version();
 
@@ -421,7 +423,9 @@ namespace Kumu
   
   void GenRandomUUID(byte_t* buf); // buf must be UUID_Length or longer
   void GenRandomValue(UUID&);
-  
+
+  void ResetTestRNG();
+
   typedef ArchivableList<UUID> UUIDList;
 
   // a self-wiping key container