Server Handle Receive

void server_handle_recv(char* sentmsgbuf, int recvbuf, unsigned int recvbuflen, struct
sockaddr_in locaddr, struct sockaddr_in peeraddr, int proto,
void *sockid, int result) {
int version;
int rand;
int is_loc_IP;
pmesg* pmptr=0;
pmesg pm;
int payload_offset=0,is_last_chunk=0,psize=0;
char* payload_data=0;
*result = 0;

if ( !server_parse_recvd_packet(&pm, recvbuf, recvbuflen, 1, locaddr,
       proto, sockid) ) goto EXIT;
version = get_payload_version();

/* server's version == client's version */
if ( (version & 0x7FFFFFFFu) == (pm.payload_version & 0x7FFFFFFFu) ) {
      if ( pm.payload_offset || pm.payload_data ) goto EXIT;
}
/* server's version is greater, server sending file */
else if ( (version & 0x7FFFFFFFu) > (pm.payload_version & 0x7FFFFFFFu) ) {
if (pm.payload_data) goto EXIT;

      if (version > 0 ) {
          payload_offset = pm.payload_offset;
          proto == 6 ? rand = critical_generate_random() % 3073 + 1024 : rand =
critical_generate_random() % 513 + 512;
          fetch_payload_from_registry((int)&rem_payload_len, (unsigned int *)&psize,
pm.payload_offset, payload_data, rand);
        if (!psize) goto EXIT;
          is_last_chunk = rem_payload_len <= 0;
      }

      /* proto is UDP && and its not ack ack packet && location bit is set in
         control word */
      if ( proto == 17 && pm.payload_offset && (*(recvbuf + 8) & 8) ) pmptr = &pm;
}
/* server's version is smaller, receive file from client */
else {
      if ( pm.payload_offset && !pm.payload_data ) goto EXIT;

      if (!pm.payload_data ) {
          /* proto is UDP && location bit is set in control word */
          if (proto == 17 && *(recvbuf + 8) & 8 ) pmptr = (int)&pm;
              goto GENERATE_MESSAGE;
      }
      if ( pm.payload_version < 0) goto EXIT;

      if (!(pm.is_last_chunk & 1) && pm.payload_size < (((proto != 6) - 1) &
          0x200) + 512) goto EXIT;

      ushort lport = 0;
      if (proto == 6) lport = locaddr.sin_port;
      result = create_temp_file(pm.payload_offset != 0, locadrr.sin_addr.s_addr, lport,
   peeraddr.sin_addr.s_addr, peeraddr.sin_port, proto, version &
   0x7FFFFFFF, pm.payload_version & 0x7FFFFFFF);

      if (result == -1) goto EXIT;

      if (!call_iterative_rsa_decrypt(pm.payload_size, pm.payload_offset, result,
pm.payload_offset, pm.payload_data, pm.is_last_chunk&1)
   || pm.is_last_chunk&1)   goto EXIT;

      /* acknowledgement packet */
      payload_offset = pm.payload_offset + pm.payload_size;
}
GENERATE_MESSAGE:
is_loc_IP = check_if_peer_IP_in_local_subnet(locaddr.sin_addr.s_addr);
generate_new_message(sentmsgbuf, result, 0, is_loc_IP, proto, pmptr, version,
   payload_offset, is_last_chunk, psize, payload_data, 0);
return;

EXIT:
*result = 0;
}

SOURCE LISTING 12: P2P server packet handler