Study network coding

Ethernet II header is 14 bytes long:

• 6 bytes for the destination MAC address
• 6 bytes for the source MAC address
• 2 bytes for the type field

type	flag
IPv4	0x0800
IPv6	0x86DD
ARP	0x0806
RARP	0x8035
MPLS	0x8847(unicast) 0x8848(multicast)
PPPoE Discovery Stage	0x8863
PPPoE Session Stage	0x8864
IEEE 802.1Q VLAN tagging	0x8100
IEEE 802.1X	0x888E

ARP protocol

IP protocol

ICMP protocol

Reference: https://en.wikipedia.org/wiki/Internet_Control_Message_Protocol

Build Ping: Echo Request, Echo Reply

HTTP/HTTPS Proxy with the hyper library

Note

Because HTTPS is encrypted, we can only see the CONNECT method with HTTPS connections in HTTP proxies, and we cannot see the real request. And the server cannot use HTTPS, it is generally HTTPS will be upgraded to the CONNECT method, and then use the HTTP protocol to communicate.

Using HTTPS server requires special client support, generally IOS and other devices do not support it.

MIMT -> Go Proxy, but it is still TCP connecting with the client, and server message is like this: TCP -> HTTP -> TLS (Proxy Request). Only maybe attacker can see the real request for MIMT.

HTTPS

Warning

If you use 0.0.0.0 as server address, and localhost has port conflict with it, then it will not report the error that the port have already been used (no error at all).

openssl req -x509 -newkey rsa:4096 -nodes -sha256 -subj /CN=localhost -keyout ssl/private.pem -out ssl/cert.pem 

smart_chat

Got inspired by this project

What is TCP packet fragmentation?

Please see the this document