corkscrew

Excepts from man corkscrew:

CORKSCREW(1)

NAME
corkscrew - Tunnel TCP connections through HTTP proxies

SYNOPSIS
corkscrew proxy proxyport targethost targetport [ authfile ]

DESCRIPTION
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corkscrew is a simple tool to tunnel TCP connections through an HTTP proxy supporting the CONNECT method. It reads stdin and writes to stdout during the connection, just like netcat. It can be used for instance to connect to an SSH server running on a remote 443 port through a strict HTTPS proxy.
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COMMON USAGE
The common usage of corkscrew is to put the following line in your ssh_config:

ProxyCommand corkscrew proxy proxyport %h %p

This will let your ssh connection go through the proxy with the help of corkscrew.