//      First/Last step packet decrypt/encrypt
//////
void __fastcall Decrypt( BYTE * Buffer )
{
   int i;
   WORD Seed = ((PAPI_PACKET)Buffer)->CryptSeed;

   if (!((PAPI_PACKET)Buffer)->CryptVer)
       return;

   for( i = 0xFE; i > 0xBD; i-- )
   {
       Seed -= *(WORD*)(Buffer + i) ^ i;
       Seed = (Seed << 0x0F) | (Seed >> 0x01);
       *(WORD*)(Buffer + i) += Seed;
   }

   for( i = 0xB8; i >= 0; i-- )
   {
       Seed += *(WORD*)(Buffer + i) ^ i;
       Seed = (Seed << 0x0F) | (Seed >> 0x01);
       *(WORD*)(Buffer + i) -= Seed;
   }

   ((PAPI_PACKET)Buffer)->CryptSeed = Seed;
}

//////////////////////////////////
void __fastcall Encrypt( BYTE * Buffer )
{
   int i;
   WORD Seed = ((PAPI_PACKET)Buffer)->CryptSeed;

   if (!((PAPI_PACKET)Buffer)->CryptVer)
       return;

   for( i = 0; i < 0xB9; i++ )
   {
       *(WORD*)(Buffer + i) += Seed;
       Seed = (Seed >> 0x0F) | (Seed << 0x01);
       Seed -= *(WORD*)(Buffer + i) ^ i;
   }

   for( i = 0xBE; i < 0xFF; i++ )
   {
       *(WORD*)(Buffer + i) -= Seed;
       Seed = (Seed >> 0x0F) | (Seed << 0x01);
       Seed += *(WORD*)(Buffer + i) ^ i;
   }

   ((PAPI_PACKET)Buffer)->CryptSeed = Seed;
}

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