Custom IP Header

# Include # define source_port 7234 # define max_receivebyte 255 typedef struct ip_hdr // define the IP header {unsigned char h_verlen; // four-bit header length, 4-bit IP version unsigned char TOS; // 8-bit service type TOS unsigned short total_len; // 16-bit total length (bytes) unsigned short ident; // 16-bit ID unsigned
Short frag_and_flags; // three-bit unsigned char TTL; // eight-bit TTL: unsigned char proto; // the eight-bit protocol (TCP, UDP, or others) unsigned short checksum; // 16-bit IP header checksum and unsigned int sourceip; // 32-bit source IP address unsigned int destip; // 32-bit destination IP address} ipheader; typedef struct tsd_hdr // define TCP pseudo header {
Unsigned long saddr; // source address unsigned long daddr; // Destination Address char mbz; char ptcl; // protocol type unsigned short tcpl; // TCP length} psdheader; typedef struct tcp_hdr // define TCP Header {ushort th_sport; // 16-bit source port ushort th_dport; // 16-bit destination port unsigned int th_seq; // 32-bit serial number unsigned int th_ack;
// 32-bit validation No. unsigned char th_lenres; // 4-bit header length/6-bit reserved characters unsigned char th_flag; // 6-Bit Flag ushort th_win; // 16-bit window size ushort th_sum; // 16-bit checksum and ushort th_urp; // 16-bit emergency data offset} tcpheader; // checksum: calculate the checksum subfunction ushort checksum (ushort * buffer, int size) {unsigned long cksum = 0;
While (size> 1) {cksum + = * buffer ++; size-= sizeof (ushort);} If (size) {cksum + = * (uchar *) buffer ;} cksum = (cksum> 16) + (cksum & 0 xFFFF); cksum + = (cksum> 16); Return (ushort )(~ Cksum);} void useage () {printf ("************************************ * ***** \ n ");
Printf ("tcpping \ n"); printf ("\ t written by refdom \ n"); printf ("\ t Email: refdom@263.net \ n"); printf ("useage: tcpping.exe target_ip target_port \ n "); printf ("************************************* * ***** \ n ");} int main (INT argc, char * argv []) {wsadata;
Socket sock; sockaddr_in addr_in; ipheader; tcpheader; psdheader; char szsendbuf [60] = {0}; bool flag; int rect, ntimeover; useage (); if (argc! = 3) {return false;} If (wsastartup (makeword (2, 2), & wsadata )! = 0) {printf ("wsastartup
Error! \ N "); Return false;} If (sock = wsasocket (af_inet, sock_raw, ipproto_raw, null, 0, wsa_flag_overlapped) = invalid_socket) {printf ("socket setup error! \ N "); Return false;} flag = true; If (setsockopt (sock, ipproto_ip, ip_hdrincl, (char *) & flag, sizeof (FLAG) = socket_error)
{Printf ("setsockopt ip_hdrincl error! \ N "); Return false;} ntimeover = 1000; If (setsockopt (sock, sol_socket, so_sndtimeo, (char *) & ntimeover, sizeof (ntimeover) = socket_error) {printf ("setsockopt so_sndtimeo error! \ N "); Return false;} addr_in.sin_family = af_inet;
Addr_in.sin_port = htons (atoi (argv [2]); addr_in.sin_addr.s_un.s_addr = inet_addr (argv [1]); // fill in the IP header ipheader. h_verlen = (4 <4 | sizeof (ipheader)/sizeof (unsigned long); // ipheader. toS = 0; ipheader. total_len = htons (sizeof (ipheader) + sizeof (tcpheader); ipheader. ident = 1;
Ipheader. frag_and_flags = 0; ipheader. TTL = 128; ipheader. PROTO = ipproto_tcp; ipheader. checksum = 0; ipheader. sourceip = inet_addr ("local address"); ipheader. destip = inet_addr (argv [1]); // fill in the TCP Header tcpheader. th_dport = htons (atoi (argv [2]); tcpheader. th_sport = htons (source_port );
// Source port number tcpheader. th_seq = htonl (0x12345678); tcpheader. th_ack = 0; tcpheader. th_lenres = (sizeof (tcpheader)/4 <4 | 0); tcpheader. th_flag = 2; // modify here to implement different flag detection, 2 is SYN, 1 is Fin, 16 is ack detection, and so on tcpheader. th_win= htons (512); tcpheader. th_urp = 0; tcpheader. th_sum = 0; psdheader. saddr = ipheader. sourceip;
Psdheader. daddr = ipheader. destip; psdheader. mbz = 0; psdheader. ptcl = ipproto_tcp; psdheader. tcpl = htons (sizeof (tcpheader); // calculate the checksum (szsendbuf, & psdheader, sizeof (psdheader); memcpy (szsendbuf + sizeof (psdheader), & tcpheader, sizeof (tcpheader); tcpheader. th_sum = checksum (ushort
*) Szsendbuf, sizeof (psdheader) + sizeof (tcpheader); memcpy (signature, & ipheader, sizeof (ipheader); memcpy (szsendbuf + sizeof (ipheader), & tcpheader, sizeof (tcpheader); memset (szsendbuf + sizeof (ipheader) + sizeof (tcpheader), 0, 4); ipheader. checksum = checksum (ushort
*) Szsendbuf, sizeof (ipheader) + sizeof (tcpheader); memcpy (szsendbuf, & ipheader, sizeof (ipheader); rect = sendto (sock, szsendbuf, sizeof (ipheader) + sizeof (tcpheader), 0, (struct sockaddr *) & addr_in, sizeof (addr_in); If (rect = socket_error) {printf ("send error! : % D \ n ", wsagetlasterror ());
Return false;} else printf ("Send OK! \ N "); closesocket (sock); wsacleanup (); Return