#! /usr/bin/env bash # source: proxy.sh # Copyright Gerhard Rieger and contributors (see file CHANGES) # Published under the GNU General Public License V.2, see file COPYING # perform primitive simulation of a proxy server. # accepts and answers correct HTTP CONNECT requests on stdio, and tries to # establish the connection to the given server. # it is required for socats test.sh # for TCP, use this script as: # socat tcp-l:8080,reuseaddr,fork exec:"proxy.sh",nofork # 20130622 GR allow hostnames, not only IP addresses if [ -z "$SOCAT" ]; then if type socat >/dev/null 2>&1; then SOCAT=socat else SOCAT="./socat" fi fi if [ $(echo "x\c") = "x" ]; then E="" elif [ $(echo -e "x\c") = "x" ]; then E="-e" else echo "cannot suppress trailing newline on echo" >&2 exit 1 fi ECHO="echo $E" CR=$($ECHO "\r") #echo "CR=$($ECHO "$CR\c" |od -c)" >&2 case `uname` in HP-UX|OSF1) # their cats are too stupid to work with unix domain sockets CAT="$SOCAT -u stdin stdout" ;; *) CAT=cat ;; esac SPACES=" " while [ -n "$1" ]; do case "$1" in -w) n="$2"; while [ "$n" -gt 0 ]; do SPACES="$SPACES "; n=$((n-1)); done shift ;; #-s) STAT="$2"; shift ;; esac shift done badrequest () { $ECHO "HTTP/1.0${SPACES}500 Bad Request$CR" $ECHO "$CR" } # read and parse HTTP request read m a h #echo "\"$m\" \"$a\" \"$h\"" >&2 if [ "$m" != 'CONNECT' ]; then badrequest; exit 1 fi if [[ "$a" == [0-9]+\.[0-9]+\.[0-9]+\.[0-9]+:[0-9]+ ]]; then : go on below elif [[ "$a" == [0-9a-zA-Z-.][0-9a-zA-Z-.]*:[0-9][0-9]* ]]; then : go on below else badrequest; exit 1 fi if [[ "$h" == HTTP/1.[01][[:space:]]* ]]; then : go on below else badrequest; exit 1 fi # read more headers until empty line while [ "$l" != "$CR" ]; do read l done # send status $ECHO "HTTP/1.0${SPACES}200 OK$CR" # send empty line $ECHO "$CR" # perform proxy (relay) function $SOCAT $SOCAT_OPTS - tcp:$a || { $ECHO "HTTP/1.0${SPACES}500 Failed to connect to $a$CR" $ECHO $CR }