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|
#include <winsock2.h>
#include<iostream>
using namespace std;
typedef struct iphdr {
unsigned char verlen; /* version du protocol IP + la longeur de l'en t?te */
unsigned char tos; /* type de service */
unsigned short tot_len; /* longueur totale du datagramme */
unsigned short id; /* identification */
unsigned short offset; /* décalage */
unsigned char ttl; /* dur?e de vie du paquet */
unsigned char protocol; /* protocole */
unsigned short checksum; /* somme de contr?le */
unsigned int saddr; /* adresse IP source */
unsigned int daddr; /* adresse IP destinataire */
} IP_HDR;
typedef struct tcphdr
{
unsigned short sport; /* port source */
unsigned short dport; /* port de destination */
unsigned int seqnum; /* num?ro de s?quence */
unsigned int acknum; /* accus? de r?ception */
unsigned char dataoffset; /* d?calage des donn?es (data offset) */
unsigned char flags; /* flags */
unsigned short windows; /* fen?tre */
unsigned short checksum; /* checksum */
unsigned short urgpointer; /* pointeur de donn?es urgentes */
} TCP_HDR;
struct pseudohdr
{
unsigned long saddr;
unsigned long daddr;
char useless;
unsigned char protocol;
unsigned short length;
struct tcphdr TCP;
};
USHORT cksum(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 & 0xffff);
cksum += (cksum >>16);
return (USHORT)(~cksum);
}
int main()
{
system("TITLE Forgeur de packet TCP");
WSADATA WSAData;
WSAStartup(MAKEWORD(2,0), &WSAData);
SOCKET socket;
socket = WSASocket(AF_INET, SOCK_RAW, IPPROTO_RAW, NULL, 0,0);
if (socket == INVALID_SOCKET)
{
fprintf(stderr, "erreur lors de la cr?ation du raw socket : %d\n", WSAGetLastError());
WSACleanup();
exit(-1);
}
int optval = 1;
if (setsockopt(socket, IPPROTO_IP, 2, (char *)&optval, sizeof(optval)) == SOCKET_ERROR)
{
fprintf(stderr, "erreur lors de l'appel ? setsockopt : %d\n", WSAGetLastError());
WSACleanup();
exit(-1);
}
//-----------------------------------remplissage en-tête de l'ip------------------------------------
unsigned short packet_size, ip_version, ip_len; /* taille de notre paquet, IP version, longueur */
struct iphdr *ip; /* notre structure IP */
/* taille de notre paquet */
packet_size = sizeof(struct iphdr) + sizeof(struct tcphdr);
/* on alloue un espace m?moire pour notre structure IP */
ip = (struct iphdr *)malloc(sizeof(struct iphdr));
/* On l'initialise ? 0 */
memset(ip, 0x0, sizeof(struct iphdr));
/* longueur de l'en t?te IP */
ip_len = sizeof(struct iphdr) / sizeof(unsigned long);
/* IP version */
ip_version = 4;
/* on remplie la structure IP */
ip->verlen = (ip_version << 4) | ip_len;
ip->tos = 0;
ip->tot_len = htons (sizeof (struct iphdr) + sizeof (struct tcphdr));
ip->id = 1;
ip->offset = 0;
ip->ttl = 255;
ip->protocol = IPPROTO_TCP;
ip->saddr = inet_addr("192.168.1.81"); /* adresse IP source */
ip->daddr = inet_addr("192.168.1.1"); /* adresse IP de destination */
ip->checksum = 0; /* on initialise le champ checksum de notre structure IP ? 0 avant l'appel de la fonction calculant le checksum */
ip->checksum = cksum((unsigned short *)ip, sizeof(struct iphdr));
//----------------------------------remplissage en-tête tcp-------------------------------------------
struct tcphdr *tcp; /* notre structure TCP */
/* maintenant passons ? la structure TCP */
/* on alloue de la m?moire pour celle ci */
tcp = (struct tcphdr *)malloc(sizeof(struct tcphdr));
memset(tcp, 0x0, sizeof(struct tcphdr));
/* on la remplie */
tcp->sport = htons(1500); /* port source */
tcp->dport = htons(80) ; /* port de destination */
tcp->seqnum = htonl(1337); /* num?ro de s?quence */
tcp->acknum = htonl(1337); /* ack number */
tcp->dataoffset = (5) << 4; /* d?calage */
tcp->flags = 0x02; /* 0x02 = flag syn */
tcp->windows = htons(1337); /* fen?tre */
tcp->checksum = 0; /* checksum */
tcp->urgpointer = 0; /* options */
//---------------------remplissage de la structure pseudo hdr pour calculer le checksum de notre packet tcp-----------------------
struct pseudohdr *psdheader; /* pseudo header */
/* allocation m?moire pour notre pseudo header */
psdheader = (struct pseudohdr *)malloc(sizeof(struct pseudohdr));
memset(psdheader, 0x0, sizeof(struct pseudohdr));
/* on remplie notre structure */
psdheader->saddr = inet_addr("192.168.1.81"); /* adresse source */
psdheader->daddr = inet_addr("192.168.1.1"); /* adresse de destination */
psdheader->useless = 0; /* null */
psdheader->protocol = IPPROTO_TCP; /* protocol */
psdheader->length = htons(sizeof(struct tcphdr)); /* longueur de notre structure TCP_HDR */
psdheader->TCP = *tcp; /* structure TCP_HDR */
/* Maintenant nous calculons le checksum pour notre paquet */
tcp->checksum =cksum((unsigned short *)psdheader, sizeof(struct pseudohdr));
char *ptr = NULL, packet[32]; /* notre paquet, 32 = sizeof(struct icmphdr) + sizeof(struct iphdr) */
ZeroMemory(packet, sizeof(packet));
ptr = packet;
memcpy(ptr, ip, sizeof(struct iphdr));
ptr += sizeof(struct iphdr);
memcpy(ptr, tcp, sizeof(struct tcphdr));
ptr += sizeof(struct tcphdr);
//-------------------------------------------------envoi du packet----------------------------------------
struct sockaddr_in sin; /* notre structure sockaddr_in qui contiendra l'adresse de destination */
/* on rempli notre structure sockaddr_in */
sin.sin_family = AF_INET;
sin.sin_addr.s_addr = inet_addr("192.168.1.1"); // Adresse de destination
/* hop, nous envoyons notre paquet ? destination */
if(sendto(socket, packet, sizeof(packet), 0x0, (struct sockaddr *)&sin, sizeof(struct sockaddr_in)) == SOCKET_ERROR)
{
fprintf(stderr, "Erreur lors de l'appel de la fonction sendto. Code erreur : %d\n", WSAGetLastError());
}
free(ip);
free(tcp);
WSACleanup();
system("pause");
return 0;} |
