Datenpakete in C++

ERit

ERit

0
hej
wollte euch fragen ob jemand schnell mal den source eines progis posten kann das ein selbst erstelltes datenpaket verschickt. wichtig wäre mir dass dieses in cpp geschrieben wurde. in perl oder python ist mir dass bekannt, aber irgendwie nicht so recht in cpp.
thx

edit: also inklusive header und checksumme usw.
 
packetgen.c
Code: 
#include "packetgen.h"

ushort checksum (unsigned short *addr, int len)
{
	unsigned short *w = addr;
	int i = len;
	int sum = 0;
	while (i > 1)
	{
		sum += *w++;
		i-=2;
	}
	if (i == 1) sum += *(u_char *)w;
	sum = (sum >> 16) + (sum & 0xffff);
	sum = sum + (sum >> 16);
	return (~sum);
}


int send_tcp(pcap_t *raw, unsigned char smac[ETH_ALEN], unsigned char dmac[ETH_ALEN], in_addr_t sip, in_addr_t dip,
							    unsigned long seq, unsigned long ack, unsigned short win, unsigned char flags,
							    unsigned short sport, unsigned short dport,
							    unsigned char* data, unsigned short datalen)
{
	char buffer[sizeof(struct ether_header) + sizeof(struct iphdr) + sizeof(struct tcphdr) + datalen];
	char pseudo[sizeof(struct pseudoheader) + sizeof(struct tcphdr) + datalen];
	struct ether_header *eth;
	struct iphdr *iph;
	struct tcphdr *tcph;
	struct pseudoheader *psh;
	
	eth  = (struct ether_header*)buffer;
	iph  = (struct iphdr*)(buffer+sizeof(struct ether_header));
	tcph = (struct tcphdr*)(buffer+sizeof(struct ether_header)+sizeof(struct iphdr));
	psh =  (struct pseudoheader*)pseudo;

	memcpy(buffer+sizeof(struct ether_header)+sizeof(struct iphdr)+sizeof(struct tcphdr), data, datalen);
	
	//ETHERNET HEADER
	eth->ether_type = htons(ETH_P_IP);
	memcpy(eth->ether_shost, smac, ETH_ALEN);
	memcpy(eth->ether_dhost, dmac, ETH_ALEN);

	//IP HEADER
	iph->ihl = 5;
	iph->version = 4;
	iph->tos = 0;
	iph->tot_len = htons(sizeof(struct iphdr)+sizeof(struct tcphdr)+datalen);
	iph->id = htons(1);
	iph->frag_off = htons(0);
	iph->ttl = 66;
		iph->protocol = IPPROTO_TCP;
		iph->check = htons(0);
		iph->saddr = sip;
		iph->daddr = dip;
	iph->check = checksum((unsigned short*)iph, sizeof(struct iphdr));

	//TCP HEADER
	tcph->th_sport = htons(sport);
	tcph->th_dport = htons(dport);
	tcph->th_seq = htonl(seq);
	tcph->th_ack = htonl(ack);
	tcph->th_x2 = 0;
	tcph->th_off = 5;
	tcph->th_flags = flags;
	tcph->th_win = htons(win);
	tcph->th_sum = 0;
	tcph->th_urp = htons(0);
	
	//PSEUDOHEADER
	psh->saddr = iph->saddr;
	psh->daddr = iph->daddr;
	psh->zero  = 0;
	psh->proto = IPPROTO_TCP;
	psh->len   = htons(sizeof(struct tcphdr)+datalen);
	memcpy(pseudo+sizeof(struct pseudoheader), tcph, sizeof(struct tcphdr));
	memcpy(pseudo+sizeof(struct pseudoheader)+sizeof(struct tcphdr), data, datalen);
	tcph->th_sum = checksum((unsigned short*)pseudo, sizeof(struct pseudoheader) + sizeof(struct tcphdr) + datalen);

	return(pcap_inject(raw, buffer, sizeof(struct ether_header)+sizeof(struct iphdr)+sizeof(struct tcphdr)+datalen)==-1);
}


//To reset a TCP-Packet, we send a RST/ACK packet with SEQ=ACK and ACK=SEQ+1 and WIN=0
void tcp_reset_packet(pcap_t * raw, struct ether_header* eth, struct iphdr* ip, struct tcphdr* tcp)
{
	send_tcp(raw, eth->ether_dhost, eth->ether_shost, ip->daddr, ip->saddr,
			htonl(tcp->th_ack), htonl(tcp->th_seq)+1, 0,
			TH_RST | TH_ACK, htons(tcp->th_dport), htons(tcp->th_sport), 0, 0);
}

packetgen.h
Code: 
#include <net/ethernet.h>
#include <netinet/ip.h>
#define __FAVOR_BSD
#include <netinet/tcp.h>
#include <stdio.h>
#define HAVE_REMOTE
#include <pcap.h>

struct pseudoheader
{
        in_addr_t	saddr;
        in_addr_t	daddr;
        unsigned char	zero;
        unsigned char	proto;
        unsigned short	len;
};


ushort checksum (unsigned short *addr, int len);

int send_tcp(pcap_t *raw, unsigned char smac[ETH_ALEN], unsigned char dmac[ETH_ALEN], in_addr_t sip, in_addr_t dip,
							    unsigned long seq, unsigned long ack, unsigned short win, unsigned char flags,
							    unsigned short sport, unsigned short dport,
							    unsigned char* data, unsigned short datalen);

void tcp_reset_packet(pcap_t * raw, struct ether_header* eth, struct iphdr* ip, struct tcphdr* tcp);

hab ich selber geschrieben deswegen keine garantie auf nix ^^

ps:
guck mal auf chaostal.org nach dem raw-socket tutorial ... 1a
 
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