proxyecho.sh

   1 #! /usr/bin/env bash
   2 # source: proxyecho.sh
   3 # Copyright Gerhard Rieger and contributors (see file CHANGES)
   4 # Published under the GNU General Public License V.2, see file COPYING
   5
   6 # perform primitive simulation of a proxy server with echo function via stdio.
   7 # accepts and answers correct HTTP CONNECT requests, but then just echoes data.
   8 # it is required for test.sh
   9 # for TCP, use this script as:
  10 # socat TCP-L:8080,reuseaddr,crlf SYSTEM:"proxyecho.sh"
  11
  12 # 20230423  GR Added option -V to require particular HTTP version
  13
  14 if type socat >/dev/null 2>&1; then
  15     SOCAT=socat
  16 else
  17     SOCAT=./socat
  18 fi
  19
  20 case `uname` in
  21 HP-UX|OSF1)
  22     CAT="$SOCAT -u stdin stdout"
  23     ;;
  24 *)
  25     CAT=cat
  26     ;;
  27 esac
  28
  29 SPACES=" " REQVER=1.0
  30 while [ -n "$1" ]; do
  31     case "$1" in
  32     -w) n="$2"; while [ "$n" -gt 0 ]; do SPACES="$SPACES "; n=$((n-1)); done
  33         shift ;;
  34     -V) shift; REQVER="$1" ;;
  35     #-s) STAT="$2"; shift ;;
  36     esac
  37     shift
  38 done
  39
  40 # read and parse HTTP request
  41 read l
  42 if ! echo "$l" |egrep '^CONNECT +[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+:[0-9]+ +HTTP/[1-3].[0-9]$' >/dev/null
  43 then
  44     echo "HTTP/1.0${SPACES}500 Bad Request"
  45     echo
  46     exit
  47 fi
  48 if ! echo "$l" |egrep '^CONNECT +[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+:[0-9]+ +HTTP/'"$REQVER"'$' >/dev/null
  49 then
  50     echo "HTTP/1.0${SPACES}426 Upgrade Required"
  51     echo
  52     exit
  53 fi
  54
  55 # read more headers until empty line
  56 while [ -n "$l" ]; do
  57     read l
  58 done
  59
  60 # send status
  61 echo "HTTP/$REQVER${SPACES}200 OK"
  62 # send empty line
  63 echo
  64
  65 # perform echo function
  66 exec $CAT