# connect to host or ip on port through the SOCKS4(a) proxy. authenticate with username (default empty)
# returns a socket that can be used to send and receive traffic from the remote host
proc socks4connect {proxy_host proxy_port host port {username {}}} {
set connect_request \x04\x01
append connect_request [binary format S $port]
if {[regexp {[0-9]+.[0-9]+.[0-9]+.[0-9]+} $host]} {
set use_host false
append connect_request [binary format c4 [split $host .]]
} else {
# ip address 0.0.0.x is always invalid and signals that a hostname is specified
set use_host true
append connect_request [binary format c4 [split 0.0.0.1 .]]
}
append connect_request $username
append connect_request \x00
if {$use_host} {
append connect_request $host
append connect_request \x00
}
set s [socket $proxy_host $proxy_port]
fconfigure $s -translation binary -buffering none
puts -nonewline $s $connect_request
set response [read $s 8]
if {[string index $response 1] ne "\x5a"} {
error "connection request rejected by proxy"
} else {
return $s
}
}
set s [socks4connect phost pport ip/host port]
# s can now be used as a normal socketA simple SOCKS 5 client library for Tcl can be found at http://github.com/dongola7/socks5
.Category Networking
