Sorry, I should've given a little more information. 192.168.1.1 is a linksys
router. Here's the command and the output. I don't understand this traffic,
but what confuses me even more is that the router is sending packets with bad
checksums...
sanctus:~ adam$ sudo tcpdump -i en2 -e -n -vvv -xx not host 192.168.1.100
tcpdump: listening on en2, link-type EN10MB (Ethernet), capture size 96 bytes
09:17:05.367722 00:0f:66:a7:b8:4b > ff:ff:ff:ff:ff:ff, ethertype IPv4 (0x0800),
length 55: IP (tos 0x0, ttl 150, id 4711, offset 0, flags [none], length: 41)
192.168.1.1.5700 > 0.0.0.0.0: . [bad tcp cksum 61da (->89e6)!] 0:1(1) ack 0 win 0
0x0000: ffff ffff ffff 000f 66a7 b84b 0800 4500 ........f..K..E.
0x0010: 0029 1267 0000 9606 50bf c0a8 0101 0000 .).g....P.......
0x0020: 0000 1644 0000 0000 0000 0000 0000 5010 ...D..........P.
0x0030: 0000 61da 0000 4e ..a...N
09:17:05.368290 00:0f:66:a7:b8:4b > ff:ff:ff:ff:ff:ff, ethertype IPv4 (0x0800),
length 55: IP (tos 0x0, ttl 150, id 4712, offset 0, flags [none], length: 41)
192.168.1.1.1119 > 0.0.0.0.0: . [bad tcp cksum 61da (->9bcb)!] 0:1(1) ack 0 win 0
0x0000: ffff ffff ffff 000f 66a7 b84b 0800 4500 ........f..K..E.
0x0010: 0029 1268 0000 9606 50be c0a8 0101 0000 .).h....P.......
0x0020: 0000 045f 0000 0000 0000 0000 0000 5010 ..._..........P.
0x0030: 0000 61da 0000 4e ..a...N
09:17:05.368926 00:0f:66:a7:b8:4b > ff:ff:ff:ff:ff:ff, ethertype IPv4 (0x0800),
length 55: IP (tos 0x0, ttl 150, id 4714, offset 0, flags [none], length: 41)
192.168.1.1.1122 > 0.0.0.0.0: . [bad tcp cksum 61da (->9bc8)!] 0:1(1) ack 0 win 0
0x0000: ffff ffff ffff 000f 66a7 b84b 0800 4500 ........f..K..E.
0x0010: 0029 126a 0000 9606 50bc c0a8 0101 0000 .).j....P.......
0x0020: 0000 0462 0000 0000 0000 0000 0000 5010 ...b..........P.
0x0030: 0000 61da 0000 4e ..a...N
09:17:05.369587 00:0f:66:a7:b8:4b > ff:ff:ff:ff:ff:ff, ethertype IPv4 (0x0800),
length 55: IP (tos 0x0, ttl 150, id 4716, offset 0, flags [none], length: 41)
192.168.1.1.1126 > 0.0.0.0.0: . [bad tcp cksum 61da (->9bc4)!] 0:1(1) ack 0 win 0
0x0000: ffff ffff ffff 000f 66a7 b84b 0800 4500 ........f..K..E.
0x0010: 0029 126c 0000 9606 50ba c0a8 0101 0000 .).l....P.......
0x0020: 0000 0466 0000 0000 0000 0000 0000 5010 ...f..........P.
0x0030: 0000 61da 0000 4e ..a...N
09:17:05.370277 00:0f:66:a7:b8:4b > ff:ff:ff:ff:ff:ff, ethertype IPv4 (0x0800),
length 55: IP (tos 0x0, ttl 150, id 4718, offset 0, flags [none], length: 41)
192.168.1.1.1129 > 0.0.0.0.0: . [bad tcp cksum 61da (->9bc1)!] 0:1(1) ack 0 win 0
0x0000: ffff ffff ffff 000f 66a7 b84b 0800 4500 ........f..K..E.
0x0010: 0029 126e 0000 9606 50b8 c0a8 0101 0000 .).n....P.......
0x0020: 0000 0469 0000 0000 0000 0000 0000 5010 ...i..........P.
0x0030: 0000 61da 0000 4e ..a...N
09:17:05.371108 00:0f:66:a7:b8:4b > ff:ff:ff:ff:ff:ff, ethertype IPv4 (0x0800),
length 55: IP (tos 0x0, ttl 150, id 4720, offset 0, flags [none], length: 41)
192.168.1.1.1132 > 0.0.0.0.0: . [bad tcp cksum 61da (->9bbe)!] 0:1(1) ack 0 win 0
0x0000: ffff ffff ffff 000f 66a7 b84b 0800 4500 ........f..K..E.
0x0010: 0029 1270 0000 9606 50b6 c0a8 0101 0000 .).p....P.......
0x0020: 0000 046c 0000 0000 0000 0000 0000 5010 ...l..........P.
0x0030: 0000 61da 0000 4e ..a...N
09:17:05.371707 00:0f:66:a7:b8:4b > ff:ff:ff:ff:ff:ff, ethertype IPv4 (0x0800),
length 55: IP (tos 0x0, ttl 150, id 4723, offset 0, flags [none], length: 41)
192.168.1.1.1137 > 0.0.0.0.0: . [bad tcp cksum 61da (->9bb9)!] 0:1(1) ack 0 win 0
0x0000: ffff ffff ffff 000f 66a7 b84b 0800 4500 ........f..K..E.
0x0010: 0029 1273 0000 9606 50b3 c0a8 0101 0000 .).s....P.......
0x0020: 0000 0471 0000 0000 0000 0000 0000 5010 ...q..........P.
0x0030: 0000 61da 0000 4e ..a...N
09:17:06.413277 00:0f:66:a7:b8:4b > ff:ff:ff:ff:ff:ff, ethertype IPv4 (0x0800),
length 55: IP (tos 0x0, ttl 150, id 4724, offset 0, flags [none], length: 41)
192.168.1.1.5700 > 0.0.0.0.0: . [bad tcp cksum 61da (->89e6)!] 0:1(1) ack 1 win 0
0x0000: ffff ffff ffff 000f 66a7 b84b 0800 4500 ........f..K..E.
0x0010: 0029 1274 0000 9606 50b2 c0a8 0101 0000 .).t....P.......
0x0020: 0000 1644 0000 0000 0000 0000 0000 5010 ...D..........P.
0x0030: 0000 61da 0000 4e ..a...N
09:17:06.414029 00:0f:66:a7:b8:4b > ff:ff:ff:ff:ff:ff, ethertype IPv4 (0x0800),
length 55: IP (tos 0x0, ttl 150, id 4725, offset 0, flags [none], length: 41)
192.168.1.1.1119 > 0.0.0.0.0: . [bad tcp cksum 61da (->9bcb)!] 0:1(1) ack 1 win 0
0x0000: ffff ffff ffff 000f 66a7 b84b 0800 4500 ........f..K..E.
0x0010: 0029 1275 0000 9606 50b1 c0a8 0101 0000 .).u....P.......
0x0020: 0000 045f 0000 0000 0000 0000 0000 5010 ..._..........P.
0x0030: 0000 61da 0000 4e ..a...N
