Started new random number generator integration.

Signed-off-by: Stefan Westerfeld <stefan@space.twc.de>

src/Makefile.am

 bin_PROGRAMS = audiowmark
 
-COMMON_SRC = utils.hh utils.cc convcode.hh convcode.cc
+COMMON_SRC = utils.hh utils.cc convcode.hh convcode.cc random.hh random.cc
 
 audiowmark_SOURCES = audiowmark.cc wavdata.cc wavdata.hh fft.cc fft.hh $(COMMON_SRC)
-audiowmark_LDFLAGS = $(SNDFILE_LIBS) $(FFTW_LIBS)
+audiowmark_LDFLAGS = $(SNDFILE_LIBS) $(FFTW_LIBS) $(LIBGCRYPT_LIBS)
 
 noinst_PROGRAMS = testconvcode testrandom
 
 testconvcode_SOURCES = testconvcode.cc $(COMMON_SRC)
+testconvcode_LDFLAGS = $(LIBGCRYPT_LIBS)
 
-testrandom_SOURCES = testrandom.cc
+testrandom_SOURCES = testrandom.cc $(COMMON_SRC)
 testrandom_LDFLAGS = $(LIBGCRYPT_LIBS)

src/audiowmark.cc

@@ -8,6 +8,7 @@
 #include "wavdata.hh"
 #include "utils.hh"
 #include "convcode.hh"
+#include "random.hh"
 
 #include <assert.h>
 
@@ -241,23 +242,12 @@ get_frame (const WavData& wav_data, int f, int ch)
   return result;
 }
 
-std::mt19937_64
-init_rng (uint64_t seed)
-{
-  const uint64_t  prime = 3126986573;
-
-  std::mt19937_64 rng;
-  rng.seed (seed + prime * Params::seed);
-
-  return rng;
-}
-
 void
 get_up_down (int f, vector<int>& up, vector<int>& down)
 {
   vector<int> used (Params::frame_size / 2);
 
-  std::mt19937_64 rng = init_rng (f); // use per frame random seed, may want to have cryptographically secure algorithm
+  Random rng (f, Random::Stream::up_down); // use per frame random seed
 
   auto choose_bands = [&used, &rng] (vector<int>& bands) {
     while (bands.size() < Params::bands_per_frame)
@@ -275,9 +265,9 @@ get_up_down (int f, vector<int>& up, vector<int>& down)
 }
 
 template<class T> void
-gen_shuffle (vector<T>& result, int seed)
+gen_shuffle (vector<T>& result, int seed, Random::Stream stream)
 {
-  std::mt19937_64 rng = init_rng (seed); // should use cryptographically secure generator, properly seeded
+  Random rng (seed, stream);
 
   // Fisher–Yates shuffle
   for (size_t i = 0; i < result.size() - 1; i++)
@@ -295,7 +285,7 @@ randomize_bit_order (const vector<T>& bit_vec, bool encode)
   for (size_t i = 0; i < bit_vec.size(); i++)
     order.push_back (i);
 
-  gen_shuffle (order, /* seed */ 0);
+  gen_shuffle (order, /* seed */ 0, Random::Stream::bit_order);
 
   vector<T> out_bits (bit_vec.size());
   for (size_t i = 0; i < bit_vec.size(); i++)
@@ -330,7 +320,7 @@ gen_mix_entries (int block)
       for (size_t i = 0; i < up.size(); i++)
         mix_entries.push_back ({ f, up[i], down[i] });
     }
-  gen_shuffle (mix_entries, /* seed */ block);
+  gen_shuffle (mix_entries, /* seed */ block, Random::Stream::mix);
   return mix_entries;
 }
 

src/random.cc

+#include "random.hh"
+
+Random::Random (uint64_t seed, Stream stream)
+{
+  std::vector<unsigned char> ctr = get_start_counter (seed, stream);
+#if 0
+  printf ("CTR: ");
+  for (auto ch : ctr)
+    printf ("%02x ", ch);
+  printf ("\n");
+#endif
+
+  gcry_error_t gcry_ret = gcry_cipher_open (&aes_ctr_cipher, GCRY_CIPHER, GCRY_CIPHER_MODE_CTR, 0);
+  die_on_error ("gcry_cipher_open", gcry_ret);
+
+  gcry_ret = gcry_cipher_setkey (aes_ctr_cipher, &aes_key[0], aes_key.size());
+  die_on_error ("gcry_cipher_setkey", gcry_ret);
+
+  gcry_ret = gcry_cipher_setctr (aes_ctr_cipher, &ctr[0], ctr.size());
+  die_on_error ("gcry_cipher_setctr", gcry_ret);
+}
+
+Random::~Random()
+{
+  gcry_cipher_close (aes_ctr_cipher);
+}
+
+std::vector<unsigned char>
+Random::get_start_counter (uint64_t seed, Stream stream)
+{
+  gcry_error_t     gcry_ret;
+  gcry_cipher_hd_t cipher_hd;
+
+  gcry_ret = gcry_cipher_open (&cipher_hd, GCRY_CIPHER, GCRY_CIPHER_MODE_ECB, 0);
+  die_on_error ("gcry_cipher_open", gcry_ret);
+
+  gcry_ret = gcry_cipher_setkey (cipher_hd, &aes_key[0], aes_key.size());
+  die_on_error ("gcry_cipher_setkey", gcry_ret);
+
+  std::vector<unsigned char> cipher_text (16);
+  std::vector<unsigned char> plain_text (16);
+
+  /* this has to be endian independent: use big endian order */
+  plain_text[0] = seed >> 56;
+  plain_text[1] = seed >> 48;
+  plain_text[2] = seed >> 40;
+  plain_text[3] = seed >> 32;
+  plain_text[4] = seed >> 24;
+  plain_text[5] = seed >> 16;
+  plain_text[6] = seed >> 8;
+  plain_text[7] = seed;
+
+  plain_text[8] = uint8_t (stream);
+
+#if 0
+  printf ("[[ ");
+  for (auto ch : plain_text)
+    printf ("%02x ", ch);
+  printf (" ]]\n");
+#endif
+
+  gcry_ret = gcry_cipher_encrypt (cipher_hd, &cipher_text[0], cipher_text.size(),
+                                             &plain_text[0],  plain_text.size());
+  die_on_error ("gcry_cipher_encrypt", gcry_ret);
+
+  gcry_cipher_close (cipher_hd);
+
+#if 0
+  printf ("[[ ");
+  for (auto ch : cipher_text)
+    printf ("%02x ", ch);
+  printf (" ]]\n");
+#endif
+
+  return cipher_text;
+}
+
+uint64_t
+Random::operator()()
+{
+  const size_t block_size = 8;
+  unsigned char zeros[block_size] = { 0, };
+  unsigned char cipher_text[block_size];
+
+  gcry_error_t gcry_ret = gcry_cipher_encrypt (aes_ctr_cipher, cipher_text, block_size, zeros, block_size);
+  die_on_error ("gcry_cipher_encrypt", gcry_ret);
+
+#if 0
+  printf ("[[ ");
+  for (auto ch : cipher_text)
+    printf ("%02x ", ch);
+  printf (" ]]\n");
+#endif
+  /* this has to be endian independent: use big endian order */
+  uint64_t result = (uint64_t (cipher_text[0]) << 56)
+                  + (uint64_t (cipher_text[1]) << 48)
+                  + (uint64_t (cipher_text[2]) << 40)
+                  + (uint64_t (cipher_text[3]) << 32)
+                  + (uint64_t (cipher_text[4]) << 24)
+                  + (uint64_t (cipher_text[5]) << 16)
+                  + (uint64_t (cipher_text[6]) << 8)
+                  + cipher_text[7];
+  return result;
+}

src/random.hh

+#ifndef AUDIOWMARK_RANDOM_HH
+#define AUDIOWMARK_RANDOM_HH
+
+#include <gcrypt.h>
+#include <stdint.h>
+
+#include <vector>
+
+class Random
+{
+public:
+  enum class Stream {
+    up_down = 1,
+    mix = 2,
+    bit_order = 3
+  };
+private:
+  std::vector<unsigned char> aes_key = std::vector<unsigned char> (16);
+  gcry_cipher_hd_t           aes_ctr_cipher;
+
+  static constexpr auto      GCRY_CIPHER = GCRY_CIPHER_AES128;
+
+  void
+  die_on_error (const char *func, gcry_error_t error)
+  {
+    if (error)
+      {
+        fprintf (stderr, "%s failed: %s/%s\n", func, gcry_strsource (error), gcry_strerror (error));
+
+        exit (1); /* can't recover here */
+      }
+  }
+  std::vector<unsigned char> get_start_counter (uint64_t seed, Stream stream);
+public:
+  Random (uint64_t seed, Stream stream);
+  ~Random();
+  uint64_t operator()();
+};
+
+#endif /* AUDIOWMARK_RANDOM_HH */

src/testrandom.cc

 #include "utils.hh"
+#include "random.hh"
 
 #include <sys/time.h>
-#include <gcrypt.h>
 
 using std::vector;
 using std::string;
@@ -15,121 +15,6 @@ gettime()
   return tv.tv_sec + tv.tv_usec / 1000000.0;
 }
 
-static constexpr auto GCRY_CIPHER = GCRY_CIPHER_AES128;
-
-class Random
-{
-  vector<unsigned char> aes_key = vector<unsigned char> (16);
-  gcry_cipher_hd_t      aes_ctr_cipher;
-
-  void
-  die_on_error (const char *func, gcry_error_t error)
-  {
-    if (error)
-      {
-        fprintf (stderr, "%s failed: %s/%s\n", func, gcry_strsource (error), gcry_strerror (error));
-
-        exit (1); /* can't recover here */
-      }
-  }
-public:
-  enum class Stream {
-    up_down = 1,
-    mix = 2,
-    bit_order = 3
-  };
-  Random (uint64_t seed, Stream stream)
-  {
-    vector<unsigned char> ctr = get_start_counter (seed, stream);
-    printf ("CTR: ");
-    for (auto ch : ctr)
-      printf ("%02x ", ch);
-    printf ("\n");
-
-    gcry_error_t gcry_ret = gcry_cipher_open (&aes_ctr_cipher, GCRY_CIPHER, GCRY_CIPHER_MODE_CTR, 0);
-    die_on_error ("gcry_cipher_open", gcry_ret);
-
-    gcry_ret = gcry_cipher_setkey (aes_ctr_cipher, &aes_key[0], aes_key.size());
-    die_on_error ("gcry_cipher_setkey", gcry_ret);
-
-    gcry_ret = gcry_cipher_setctr (aes_ctr_cipher, &ctr[0], ctr.size());
-    die_on_error ("gcry_cipher_setctr", gcry_ret);
-  }
-  ~Random()
-  {
-    gcry_cipher_close (aes_ctr_cipher);
-  }
-  vector<unsigned char>
-  get_start_counter (uint64_t seed, Stream stream)
-  {
-    gcry_error_t     gcry_ret;
-    gcry_cipher_hd_t cipher_hd;
-
-    gcry_ret = gcry_cipher_open (&cipher_hd, GCRY_CIPHER, GCRY_CIPHER_MODE_ECB, 0);
-    die_on_error ("gcry_cipher_open", gcry_ret);
-
-    gcry_ret = gcry_cipher_setkey (cipher_hd, &aes_key[0], aes_key.size());
-    die_on_error ("gcry_cipher_setkey", gcry_ret);
-
-    vector<unsigned char> cipher_text (16);
-    vector<unsigned char> plain_text (16);
-
-    /* this has to be endian independent: use big endian order */
-    plain_text[0] = seed >> 56;
-    plain_text[1] = seed >> 48;
-    plain_text[2] = seed >> 40;
-    plain_text[3] = seed >> 32;
-    plain_text[4] = seed >> 24;
-    plain_text[5] = seed >> 16;
-    plain_text[6] = seed >> 8;
-    plain_text[7] = seed;
-
-    plain_text[8] = uint8_t (stream);
-
-    printf ("[[ ");
-    for (auto ch : plain_text)
-      printf ("%02x ", ch);
-    printf (" ]]\n");
-
-    gcry_ret = gcry_cipher_encrypt (cipher_hd, &cipher_text[0], cipher_text.size(),
-                                               &plain_text[0],  plain_text.size());
-    die_on_error ("gcry_cipher_encrypt", gcry_ret);
-
-    gcry_cipher_close (cipher_hd);
-
-    printf ("[[ ");
-    for (auto ch : cipher_text)
-      printf ("%02x ", ch);
-    printf (" ]]\n");
-
-    return cipher_text;
-  }
-  uint64_t operator()()
-  {
-    const size_t block_size = 8;
-    unsigned char zeros[block_size] = { 0, };
-    unsigned char cipher_text[block_size];
-
-    gcry_error_t gcry_ret = gcry_cipher_encrypt (aes_ctr_cipher, cipher_text, block_size, zeros, block_size);
-    die_on_error ("gcry_cipher_encrypt", gcry_ret);
-
-    printf ("[[ ");
-    for (auto ch : cipher_text)
-      printf ("%02x ", ch);
-    printf (" ]]\n");
-    /* this has to be endian independent: use big endian order */
-    uint64_t result = (uint64_t (cipher_text[0]) << 56)
-                    + (uint64_t (cipher_text[1]) << 48)
-                    + (uint64_t (cipher_text[2]) << 40)
-                    + (uint64_t (cipher_text[3]) << 32)
-                    + (uint64_t (cipher_text[4]) << 24)
-                    + (uint64_t (cipher_text[5]) << 16)
-                    + (uint64_t (cipher_text[6]) << 8)
-                    + cipher_text[7];
-    return result;
-  }
-};
-
 int
 main (int argc, char **argv)
 {