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--- dsniff-2.4.orig/tcpkill.c 2001-03-17 09:10:43.000000000 +0100
+++ dsniff-2.4/tcpkill.c 2009-12-11 12:59:42.000000000 +0100
@@ -39,17 +39,18 @@ usage(void)
static void
tcp_kill_cb(u_char *user, const struct pcap_pkthdr *pcap, const u_char *pkt)
{
- struct libnet_ip_hdr *ip;
+ struct libnet_ipv4_hdr *ip;
struct libnet_tcp_hdr *tcp;
- u_char ctext[64], buf[IP_H + TCP_H];
+ u_char ctext[64];
u_int32_t seq, win;
- int i, *sock, len;
+ int i, len;
+ libnet_t *l;
- sock = (int *)user;
+ l = (libnet_t *)user;
pkt += pcap_off;
len = pcap->caplen - pcap_off;
- ip = (struct libnet_ip_hdr *)pkt;
+ ip = (struct libnet_ipv4_hdr *)pkt;
if (ip->ip_p != IPPROTO_TCP)
return;
@@ -57,34 +58,31 @@ tcp_kill_cb(u_char *user, const struct p
if (tcp->th_flags & (TH_SYN|TH_FIN|TH_RST))
return;
- libnet_build_ip(TCP_H, 0, 0, 0, 64, IPPROTO_TCP,
- ip->ip_dst.s_addr, ip->ip_src.s_addr,
- NULL, 0, buf);
-
- libnet_build_tcp(ntohs(tcp->th_dport), ntohs(tcp->th_sport),
- 0, 0, TH_RST, 0, 0, NULL, 0, buf + IP_H);
-
seq = ntohl(tcp->th_ack);
win = ntohs(tcp->th_win);
snprintf(ctext, sizeof(ctext), "%s:%d > %s:%d:",
- libnet_host_lookup(ip->ip_src.s_addr, 0),
+ libnet_addr2name4(ip->ip_src.s_addr, LIBNET_DONT_RESOLVE),
ntohs(tcp->th_sport),
- libnet_host_lookup(ip->ip_dst.s_addr, 0),
+ libnet_addr2name4(ip->ip_dst.s_addr, LIBNET_DONT_RESOLVE),
ntohs(tcp->th_dport));
- ip = (struct libnet_ip_hdr *)buf;
- tcp = (struct libnet_tcp_hdr *)(ip + 1);
-
for (i = 0; i < Opt_severity; i++) {
- ip->ip_id = libnet_get_prand(PRu16);
seq += (i * win);
- tcp->th_seq = htonl(seq);
- libnet_do_checksum(buf, IPPROTO_TCP, TCP_H);
+ libnet_clear_packet(l);
- if (libnet_write_ip(*sock, buf, sizeof(buf)) < 0)
- warn("write_ip");
+ libnet_build_tcp(ntohs(tcp->th_dport), ntohs(tcp->th_sport),
+ seq, 0, TH_RST, 0, 0, 0, LIBNET_TCP_H,
+ NULL, 0, l, 0);
+
+ libnet_build_ipv4(LIBNET_IPV4_H + LIBNET_TCP_H, 0,
+ libnet_get_prand(LIBNET_PRu16), 0, 64,
+ IPPROTO_TCP, 0, ip->ip_dst.s_addr,
+ ip->ip_src.s_addr, NULL, 0, l, 0);
+
+ if (libnet_write(l) < 0)
+ warn("write");
fprintf(stderr, "%s R %lu:%lu(0) win 0\n", ctext, seq, seq);
}
@@ -95,8 +93,10 @@ main(int argc, char *argv[])
{
extern char *optarg;
extern int optind;
- int c, sock;
+ int c;
char *p, *intf, *filter, ebuf[PCAP_ERRBUF_SIZE];
+ char libnet_ebuf[LIBNET_ERRBUF_SIZE];
+ libnet_t *l;
pcap_t *pd;
intf = NULL;
@@ -136,14 +136,14 @@ main(int argc, char *argv[])
if ((pcap_off = pcap_dloff(pd)) < 0)
errx(1, "couldn't determine link layer offset");
- if ((sock = libnet_open_raw_sock(IPPROTO_RAW)) == -1)
+ if ((l = libnet_init(LIBNET_RAW4, intf, libnet_ebuf)) == NULL)
errx(1, "couldn't initialize sending");
- libnet_seed_prand();
+ libnet_seed_prand(l);
warnx("listening on %s [%s]", intf, filter);
- pcap_loop(pd, -1, tcp_kill_cb, (u_char *)&sock);
+ pcap_loop(pd, -1, tcp_kill_cb, (u_char *)l);
/* NOTREACHED */
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