easy_shell_proxy

easy_shell_proxy.sh

#
# Functions used to change or display the proxy state
#

# usually it's all the same host, but you could add more host vars if needed
_PROXY_HOST="proxy.company.com"
_HPROXY_PORT="8080"
_HSPROXY_PORT="8080"
_SPROXY_PORT="1080" # this is usually different than http/s
# comma separated (no spaces) list of hosts/ip ranges(cidr) to not proxy
_PROXY_EXCEPTIONS="localhost,127.0.0.0/8,10.0.0.0/8,192.168.0.0/16"

# if an investigate function isn't already defined, define one
# allows you to easily debug variables as varname:varvalue or similar
if ! type -t investigate &> /dev/null; then
  investigate() {
    # if $3 isn't given, don't prefix output with anything
    local output_prefix='' # could be something like [*]
    if [ -n "$3" ]; then output_prefix="$3";fi
  
    # if $2 isn't given, default separator to something
    local output_sep=": " # could be ", " ": " etc
    if [ -n "$2" ]; then output_sep="$2";fi
  
    # if $1 is given, then good, if not, well jeez, don't do anything
    local var2investigate=''
    if [ -n "$1" ]; then
      var2investigate="$1"
      echo -n "${output_prefix}${var2investigate}${output_sep}"
      v='echo -n $'
      v="${v}$(echo -n $var2investigate)"
      eval $v
      echo
    fi
  }

  # might as well make this function available for the shell user
  export -f investigate
fi

# we don't use "HTTP_PROXY" or "http_proxy" to avoid interfering w/any env vars

# most http proxies can be constructed thusly ;)
_HTTP_PROXY=http://${_PROXY_HOST}:${_HPROXY_PORT}
# some https proxies use http://, some use https://, change as needed
# some https proxies use a different port than the http one, change as needed
_HTTPS_PROXY=http://${_PROXY_HOST}:${_HSPROXY_PORT}

_SOCKS_PROXY=socks://${_PROXY_HOST}:${_SPROXY_PORT}

# define the functions to be used in the shell
proxyon() {
  # if first arg is -s then don't mess w/socks stuff
  local no_socks=$1
  
  export http_proxy=$_HTTP_PROXY
  export https_proxy=$_HTTPS_PROXY
  [ -z "$no_socks" ] && export socks_proxy=$_SOCKS_PROXY
  export no_proxy=$_PROXY_EXCEPTIONS
}
proxyoff() {
  # if first arg is -s then don't mess w/socks stuff
  local no_socks=$1
  
  unset http_proxy
  unset https_proxy
  [ -z "$no_socks" ] && unset socks_proxy
  unset no_proxy
}

# Display the state of the proxy variables
proxystate() {
  # if first arg is -s then don't show state of socks proxy
  local no_socks=$1
  
  local HTTP="off"
  local HTTPS="off"
  local SOCKS="off"
  local EXCEPTS="none"
  export | grep -q http_proxy && HTTP=$http_proxy
  export | grep -q https_proxy && HTTPS=$https_proxy
  export | grep -q socks_proxy && SOCKS=$socks_proxy
  export | grep -q no_proxy && EXCEPTS=$no_proxy 
  # Show the current state of proxy variables
  vars2show="HTTP HTTPS EXCEPTS"
  [ -z "$no_socks" ] && vars2show="$vars2show SOCKS"
  for proto in $vars2show; do investigate $proto;done
}
export -f proxystate

# as soon as this file is sourced, turn the proxy on
proxyon

updated w/no_proxy settings & simplified some checks

I didn't add the 172 net cuz people who use that are evil and/or masochistic ;)