DMR: Auctus / GoComm Encryption Support w/ Forced Application; #346

Use -, Secure04 to use this mode;

examples/cygwin_bat/complete_usage_options.txt

@@ -1,4 +1,4 @@
-Build Version: AW 2026-30-g43d63b2 
+Build Version: AW 2026-36-g5e5c3c4 
 MBElib Version: 1.3.4
 CODEC2 Support Enabled
 
@@ -175,6 +175,9 @@ Advanced Decoder options:
                  
   -A <hex>      Manually Enter and Enforce Anytone 16-bit BP Key Value (DMR) (Hex Value) 
                  
+  -, <string>   Manually Enter and Enforce Auctus A6 (GoComm) 8 Char Key Value (DMR) (String Value) 
+                 -,  Secure04
+                 
   -S <str>      Manually Enter and Enforce Generic Static Keystream -> Length and BYTE PACKED / ALIGNED String for AMBE (up to 882 bits)
                   For Example, enter 16-bit Keystream 0909 as:
                     -S 16:0909

include/dsd.h

@@ -1648,6 +1648,7 @@ void anytone_bp_keystream_creation(dsd_state * state, char * input);
 void baofeng_ap_pc5_keystream_creation(dsd_state *state, char *input);
 void csi72_ambe2_codeword_keystream(dsd_state * state, char ambe_fr[4][24]);
 void straight_mod_xor_keystream_creation(dsd_state * state, char * input);
+void auctus_keystream_creation(dsd_state * state, char * input);
 
 //Kirisun
 uint32_t kirisun_lfsr(unsigned long long int mi);

src/crypt-rc4.c

@@ -143,4 +143,105 @@ void hytera_enhanced_rc4_setup(dsd_opts * opts, dsd_state * state, unsigned long
   //end line break
   // fprintf (stderr, "\n");
 
-}
+}
+
+void rc_poor_keystream_output(uint8_t * key, uint8_t * ks_bytes)
+{
+  int16_t i, j, x, count;
+  uint8_t t, b;
+
+  //init Sbox
+  uint8_t S[255];
+  for(i = 0; i < 255; i++)
+    S[i] = i;
+
+  //Key Scheduling
+  j = 0;
+  for(i = 0; i < 255; i++)
+  {
+    j = (j + S[i] + key[i % 8]) % 255;
+    t = S[i];
+    S[i] = S[j];
+    S[j] = t;
+  }
+
+  //KS Byte collection
+  i = j = x = 0;
+  for(count = 0; count < 6; count++)
+  {
+    i = (i + 1) % 255;
+    j = (j + S[i]) % 255;
+    t = S[i];
+    S[i] = S[j];
+    S[j] = t;
+    b = (S[i] + S[j]) % 255;
+    ks_bytes[x++] = b;
+  }
+
+}
+
+void auctus_keystream_creation(dsd_state * state, char * input)
+{
+
+  uint8_t key[8];
+  memset (key, 0, sizeof(key));
+
+  uint16_t len = strlen((const char*)input);
+
+  //sanity check on provided char len
+  if (len > 8)
+    len = 8;
+
+  //load chars as uint8_t into key array
+  for (int i = 0; i < len; i++)
+    key[i] = (uint8_t)input[i];
+
+  //debug
+  fprintf (stderr, "Key String: %s; LEN: %d; HEX: ", input, len);
+  for (int i = 0; i < len; i++)
+    fprintf (stderr, "%02X", key[i]);
+  fprintf (stderr, "\n");
+
+  uint8_t ks_bytes[6];
+  memset (ks_bytes, 0, sizeof(ks_bytes));
+
+  rc_poor_keystream_output(key, ks_bytes);
+
+  uint8_t ks_bits[48];
+  memset(ks_bits, 0, sizeof(ks_bits));
+  unpack_byte_array_into_bit_array(ks_bytes, ks_bits, 6);
+
+  //Reorder the bits of the keystream to compensate
+  //for 16-bit words with reversed bit storage
+  for (uint16_t j = 0; j < 3; j++)
+  {
+    uint16_t k = ((j+1)*16) - 1;
+    uint16_t x = j*16;
+    for (uint16_t i = 0; i < 16; i++)
+    {
+      state->static_ks_bits[0][x] = ks_bits[k];
+      state->static_ks_bits[1][x] = ks_bits[k];
+
+      //debug
+      // fprintf (stderr, " K: %02d; ", k);
+      
+      //debug
+      // fprintf (stderr, " X: %02d; ", x);
+
+      k--;
+      x++;
+    }
+  }
+
+  fprintf (stderr,"Auctus Keystream: ");
+  for (uint16_t i = 0; i < 6; i++)
+    fprintf (stderr, "%02X", ks_bytes[i]);
+  fprintf (stderr," - Word Bit Reverse: ");
+  for (uint16_t i = 0; i < 6; i++)
+    fprintf (stderr, "%02X", convert_bits_into_output(state->static_ks_bits[0]+(i*8), 8));
+  fprintf (stderr, " with Forced Application \n");
+
+  state->straight_ks = 1;
+  state->straight_mod = 49;
+
+}

src/dsd_main.c

@@ -1571,6 +1571,9 @@
    printf ("                 \n");
    printf ("  -A <hex>      Manually Enter and Enforce Anytone 16-bit BP Key Value (DMR) (Hex Value) \n");
    printf ("                 \n");
+   printf ("  -, <string>   Manually Enter and Enforce Auctus A6 (GoComm) 8 Char Key Value (DMR) (String Value) \n");
+   printf ("                 -,  Secure04\n");
+   printf ("                 \n");
    printf ("  -S <str>      Manually Enter and Enforce Generic Static Keystream -> Length and BYTE PACKED / ALIGNED String for AMBE (up to 882 bits)\n");
    printf ("                  For Example, enter 16-bit Keystream 0909 as:\n");
    printf ("                    -S 16:0909\n");
@@ -1898,7 +1901,7 @@
  
    exitflag = 0;
  
-   while ((c = getopt (argc, argv, "~yhaepPqs:t:v:z:i:o:d:c:g:n:w:B:C:R:f:m:u:x:A:S:G:D:L:V:U:YK:b:H:X:M:NQ:WrlZTF@:!:01:2:345:6:^:7:8_:9:Ek:I:J:O+:j:")) != -1)
+   while ((c = getopt (argc, argv, "~yhaepPqs:t:v:z:i:o:d:c:g:n:w:B:C:R:f:m:u:x:A:S:G:D:L:V:U:YK:b:H:X:M:NQ:WrlZTF@:!:01:2:345:6:^:7:8_:9:Ek:I:J:O+:j:,:")) != -1)
      {
  
        switch (c)
@@ -2017,6 +2020,11 @@
            baofeng_ap_pc5_keystream_creation(&state, optarg);
            break;
 
+         //Auctus (GoComm) Keystream Creation
+         case ',':
+           auctus_keystream_creation(&state, optarg);
+           break;
+
          //Straight KS Generation
          case 'S':
            straight_mod_xor_keystream_creation(&state, optarg);