Allow setting AES key for test purposes using --test-key.

Old style --seed is no longer supported; replaced it with --test-key in
test scripts.
Signed-off-by: Stefan Westerfeld <stefan@space.twc.de>

src/audiowmark.cc

@@ -31,7 +31,7 @@ namespace Params
   static bool mix              = true;
   static bool hard             = false; // hard decode bits? (soft decoding is better)
   static int block_size        = 32;    // block size for mix step (non-linear bit storage)
-  static unsigned int seed     = 0;
+  static int have_key          = 0;
   static size_t payload_size   = 128;  // number of payload bits for the watermark
 }
 
@@ -158,9 +158,10 @@ parse_options (int   *argc_p,
 	{
           Params::hard = true;
 	}
-      else if (check_arg (argc, argv, &i, "--seed", &opt_arg))
+      else if (check_arg (argc, argv, &i, "--test-key", &opt_arg))
 	{
-          Params::seed = atoi (opt_arg);
+          Params::have_key++;
+          Random::set_global_test_key (atoi (opt_arg));
 	}
     }
 
@@ -888,6 +889,11 @@ main (int argc, char **argv)
 {
   parse_options (&argc, &argv);
 
+  if (Params::have_key > 1)
+    {
+      fprintf (stderr, "audiowmark: watermark key can at most be set once (--key / --test-key option)\n");
+      return 1;
+    }
   string op = (argc >= 2) ? argv[1] : "";
 
   if (op == "add" && argc == 5)

src/ber-test.sh

@@ -44,7 +44,7 @@ do
       PATTERN=4e1243bd22c66e76c2ba9eddc1f91394
     fi
 
-    audiowmark add "$i" ${AWM_FILE}.wav $PATTERN $AWM_PARAMS --seed $SEED >/dev/null
+    audiowmark add "$i" ${AWM_FILE}.wav $PATTERN $AWM_PARAMS --test-key $SEED >/dev/null
     if [ "x$TRANSFORM" == "xmp3" ]; then
       if [ "x$2" == "x" ]; then
         echo "need mp3 bitrate" >&2
@@ -93,9 +93,9 @@ do
       exit 1
     fi
     # blind decoding
-    audiowmark cmp ${AWM_FILE}.wav $PATTERN $AWM_PARAMS --seed $SEED
+    audiowmark cmp ${AWM_FILE}.wav $PATTERN $AWM_PARAMS --test-key $SEED
     # decoding with original
-    # audiowmark cmp-delta "$i" t.wav $PATTERN $AWM_PARAMS --seed $SEED
+    # audiowmark cmp-delta "$i" t.wav $PATTERN $AWM_PARAMS --test-key $SEED
   done
 done | grep bit_error_rate | {
   if [ "x$AWM_REPORT" == "xber" ]; then

src/random.cc

 #include "random.hh"
 
+static std::vector<unsigned char> aes_key (16);
+static constexpr auto             GCRY_CIPHER = GCRY_CIPHER_AES128;
+
+static void
+uint64_to_buffer (uint64_t       u,
+                  unsigned char *buffer)
+{
+  /* this has to be endian independent: use big endian order */
+  buffer[0] = u >> 56;
+  buffer[1] = u >> 48;
+  buffer[2] = u >> 40;
+  buffer[3] = u >> 32;
+  buffer[4] = u >> 24;
+  buffer[5] = u >> 16;
+  buffer[6] = u >> 8;
+  buffer[7] = u;
+}
+
+static uint64_t
+uint64_from_buffer (unsigned char *buffer)
+{
+  /* this has to be endian independent: use big endian order */
+  return (uint64_t (buffer[0]) << 56)
+       + (uint64_t (buffer[1]) << 48)
+       + (uint64_t (buffer[2]) << 40)
+       + (uint64_t (buffer[3]) << 32)
+       + (uint64_t (buffer[4]) << 24)
+       + (uint64_t (buffer[5]) << 16)
+       + (uint64_t (buffer[6]) << 8)
+       + buffer[7];
+}
+
 Random::Random (uint64_t seed, Stream stream)
 {
   std::vector<unsigned char> ctr = get_start_counter (seed, stream);
@@ -40,15 +72,7 @@ Random::get_start_counter (uint64_t seed, Stream stream)
   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;
+  uint64_to_buffer (seed, &plain_text[0]);
 
   plain_text[8] = uint8_t (stream);
 
@@ -91,14 +115,11 @@ Random::operator()()
     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;
+  return uint64_from_buffer (&cipher_text[0]);
+}
+
+void
+Random::set_global_test_key (uint64_t key)
+{
+  uint64_to_buffer (key, &aes_key[0]);
 }

src/random.hh

@@ -15,11 +15,8 @@ public:
     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)
   {
@@ -35,6 +32,8 @@ public:
   Random (uint64_t seed, Stream stream);
   ~Random();
   uint64_t operator()();
+
+  static void set_global_test_key (uint64_t seed);
 };
 
 #endif /* AUDIOWMARK_RANDOM_HH */

src/testrandom.cc

@@ -24,4 +24,16 @@ main (int argc, char **argv)
       uint64_t x = rng();
       printf ("%016lx\n", x);
     }
+
+  uint64_t s = 0;
+  double t_start = gettime();
+  size_t runs = 1000000;
+  for (size_t i = 0; i < runs; i++)
+    {
+      s += rng();
+    }
+  double t_end = gettime();
+  printf ("s=%016lx\n\n", s);
+
+  printf ("%f Mvalues/sec\n", runs / (t_end - t_start) / 1000000);
 }