Pcap 
Pcap contains libpcap bindings for Julia as well as logic to parse and extract useful data from packet captures
Example
function display_eth_hdr(ethhdr::EthHdr)
println("Ethernet Header")
println(" |- Src Mac : $(ethhdr.src_mac)")
println(" |- Dest Mac : $(ethhdr.dest_mac)")
println(" |- Type : $(ethhdr.ptype)")
end # function display_ip_hdr
function display_ip_hdr(iphdr::IpHdr)
println("IP Header")
println(" |- Version : $(iphdr.version)")
println(" |- Length : $(iphdr.length)")
println(" |- Type of Service : $(iphdr.services)")
println(" |- Total Length : $(iphdr.totlen)")
println(" |- ID : $(iphdr.id)")
println(" |- TTL : $(iphdr.ttl)")
println(" |- Protocol : $(iphdr.protocol)")
println(" |- Src Ip : $(iphdr.src_ip)")
println(" |- Dest Ip : $(iphdr.dest_ip)")
println(" |- Checksum : 0x$(hex(iphdr.checksum,4))")
end # function display_ip_hdr
function display_udp_hdr(udphdr::UdpHdr)
println("UDP Header")
println(" |- Src Port : $(udphdr.src_port)")
println(" |- Dest Port : $(udphdr.dest_port)")
println(" |- Length : $(udphdr.length)")
println(" |- Checksum : 0x$(hex(udphdr.checksum, 4))")
print(" |- Data : ")
n = 0
for byte = udphdr.data
if n % 16 == 0 && n != 0
print("\n ")
end
print("$(hex(byte, 2)) ")
n = n + 1
end
end # function display_udp_hdr
cap = PcapOffline("data/dns-query-response.pcap")
rec = pcap_get_record(cap)
layers = decode_pkt(rec.payload)
println("---------- UDP Packet ----------\n")
display_eth_hdr(layers.datalink)
display_ip_hdr(layers.network)
if (layers.network.protocol == 17)
display_udp_hdr(layers.protocol)
end
println("\n\n--------------------------------\n")Output
---------- UDP Packet ----------
Ethernet Header
|- Src Mac : 74:de:2b:08:78:09
|- Dest Mac : 00:24:fe:b1:8f:dc
|- Type : 2048
IP Header
|- Version : 4
|- Length : 20
|- Type of Service : 0
|- Total Length : 63
|- ID : 20831
|- TTL : 64
|- Protocol : 17
|- Src Ip : 192.168.0.51
|- Dest Ip : 192.168.0.1
|- Checksum : 0x67ca
UDP Header
|- Src Port : 34904
|- Dest Port : 53
|- Length : 43
|- Checksum : 0xa24a
|- Data : 56 6d 01 00 00 01 00 00 00 00 00 00 0d 66 65 64
6f 72 61 70 72 6f 6a 65 63 74 03 6f 72 67 00 00
01 00 01
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