diff options
| -rwxr-xr-x | crafted-pkt/retransmit-overlap.py | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/crafted-pkt/retransmit-overlap.py b/crafted-pkt/retransmit-overlap.py new file mode 100755 index 0000000..31fcfc5 --- /dev/null +++ b/crafted-pkt/retransmit-overlap.py @@ -0,0 +1,43 @@ +#!/usr/bin/env python +import argparse + +from scapy.all import * + +parser = argparse.ArgumentParser() +parser.add_argument("-w", dest="output_file", required=True, + help="Output pcap file") +args = parser.parse_args() + + +pkttime = 0 + + +def tcp(data=b'', datalen=0, seq=None, rexmit=False): + assert len(data) == datalen + global pkttime + relseq = seq + seq += 4096 + ip = IP(src='10.0.0.2', dst='10.0.0.1') + pkt = ip/TCP(flags='A', sport=32323, dport=25, ack=1024, seq=seq)/data + if rexmit: + pkttime += .1 + else: + pkttime += .01 + pkt.time = pkttime + return pkt + + +pkts = [ + tcp(seq=0, data=b'DATA\r\n', datalen=6), + tcp(seq=6, data=b'To: <root@example.com>\r\n\r\n', datalen=26), + tcp(seq=32, data=b'1:segment that is fully rexmit.\n', datalen=32), + tcp(seq=32, data=b'1:segment that is fully rexmit.\n'+b'2', datalen=33, rexmit=True), + tcp(seq=64, data=b'2:first char (2) part of rexmit\n', datalen=32, rexmit=True), + tcp(seq=96, data=b"3:line that isn't retransmitted\n", datalen=32), + tcp(seq=128, data=b"4:retransmission after this:XYZ\n", datalen=32), + tcp(seq=160-4, data=b"XYZ\n"+b"5:new part after retransmission\n", datalen=4+32, rexmit=True), + tcp(seq=192, data=b"6:FINAL LINE, NOT RETRANSMITTED\n", datalen=32), + tcp(seq=224, data=b'\r\n.\r\n', datalen=5), +] + +wrpcap(args.output_file, pkts) |