I want to modify icmp.unused value in scapy. But no matter what value I set for it, the value of icmp.unused is still 0. I know which byte in my packet is responsible for its value. So I want to modify the byte directly. hexstr and hexdump don't work. The end of the packet is messed up. How to do this?
hex_packet = scapy.hexstr(packet)
print(type(hex_packet))
list_packet = list(hex_packet)
list_packet[38] = '\x05'
list_packet[39] = '\x14'
hex_packet = ''.join(list_packet)
packet_hex = scapy.Ether(scapy.import_hexcap())
08 00 27 78 FE 4B 52 54 00 12 35 00 080 45 00 00 38 00 01 00 00 40 01 31 6D C0 A8 64 01 C0 A8 64 05 03 04 41 5E 00 00 05 14 45 00 00 1C 00 01 00 00 40 11 31 74 C0 A8 64 05 C0 A8 64 06 FC F1 00 35 00 08 B9 5A ..'x.KRT..5...E..8....@.1m..d...d...A^....E.......@.1t..d...d....5...Z