#! /bin/sh # source: ftp.sh # Copyright Gerhard Rieger and contributors (see file CHANGES) # Published under the GNU General Public License V.2, see file COPYING # example how to write a shell script that communicates with stdio on the front # end and with a socat address on the back end # usage: # ftp.sh [opts] server directory/ # show directory contents on stdout # ftp.sh [opts] server file # print file contents to stdout # opts: # -socks socksserver # use given socks server, port 1080 # -proxy proxyserver # use given proxy server, port 8080 # # must be http proxy that accepts CONNECT # # method to ports 21 and >=1024 # -user username # default: "ftp" # -passwd password # default: "anonymous@domain.org" # -t # shell script trace+debug # -d # debug on control connection (use up to 4 times) # -D # debug on data connection (use up to 4 times) # -b # block size for data connection # -v # verbose # -l* # socat logging options # example: # ftp.sh -v -d -d -D -D -D -b 65536 -proxy proxy ftp.ftp.org /README >README user="ftp" passwd="anonymous@domain.org" #method="socks4:socks" # socks4 is address spec, socks is socks server name method=tcp addropts= # socat options SO1= SO2= while :; do case "$1" in -socks|-socks4) shift; case "$1" in *:*) method="socks4:${1%%:*}"; addropts="socksport=${1#*:}" ;; *) method="socks4:$1" ;; esac ;; -socks4a) shift; case "$1" in *:*) method="socks4a:${1%%:*}"; addropts="socksport=${1#*:}" ;; *) method="socks4a:$1" ;; esac ;; -proxy) shift; case "$1" in *:*) method="proxy:${1%%:*}"; addropts="proxyport=${1#*:}" ;; *) method="proxy:$1" ;; esac ;; -user) shift; user="$1" ;; -passwd) shift; passwd="$1" ;; -t) set -vx ;; -d) SO1="$SO1 -d" ;; -D) SO2="$SO2 -d" ;; -b) SO2="$SO2 -b $2"; shift ;; -v) SO1="$SO1 -v" ;; -l*) SO1="$SO1 $1"; SO2="$SO2 $1" ;; -*) echo "unknown option \"$1\"" >&2; exit 1;; *) break ;; esac shift done export SO2 server="$1" dir="$2" echo "addr=$method:$server:21,$addropts"; exit ### this is the central part to establish communication with socat ### ### copy these lines to make new communication shell scripts TMPDIR=$(if [ -x /bin/mktemp ]; then /bin/mktemp -d /tmp/$USER/FTPSH.XXXXXX else (umask 077; d=/tmp/$USER/FTPSH.$$; mkdir $d; echo $d) fi) TO="$TMPDIR/to"; FROM="$TMPDIR/from" socat $SO1 fifo:$TO,nonblock,ignoreeof!!fifo:$FROM $method:$server:21,$addropts & S1=$! while ! [ -p "$TO" -a -p "$FROM" ]; do sleep 1; done exec 4>$TMPDIR/to 3<$TMPDIR/from trap "S1=" 17 #trap "echo cleaning up...>&2; rm -r $TMPDIR; [ -n "$S1" ] && kill $S1" 0 3 trap "rm -r $TMPDIR" 0 3 ### here the central part ends # this function waits for a complete server message, checks if its status # is in the permitted range (terminates session if not), and returns. ftp_chat () { local cmd="$1" local errlevel="$2"; [ -z "$errlevel" ] && errlevel=300 if [ -n "$cmd" ]; then echo "$cmd" >&4; fi while read status message <&3; ( case "$status" in [0-9][0-9][0-9]-*) exit 0;; [0-9][0-9][0-9]*) exit 1;; *) exit 1;; esac ) do :; done #echo "got \"$status $message\"" >&2 if [ -z "$status" ]; then echo ftp data connection failed >&2; exit; fi if [ "$status" -ge "$errlevel" ]; then echo $message >&2 echo "QUIT" >&4; exit 1 fi set +vx } # wait for server greeting ftp_chat ftp_chat "USER $user" 400 ftp_chat "PASS $passwd" #ftp_chat "CWD $dir" case "$dir" in */) ftp_chat "TYPE A" ;; *) ftp_chat "TYPE I" ;; esac echo "PASV" >&4; read status message <&3 info=$(expr "$message" : '.*[^0-9]\([0-9]*,[0-9]*,[0-9]*,[0-9]*,[0-9]*,[0-9]*\).*') echo $info |tr ',' ' ' |(read i1 i2 i3 i4 p1 p2 addr=$i1.$i2.$i3.$i4 port=$(echo "256*$p1+$p2" |bc) #echo $addr:$port trap : 20 # open data connection and transfer data socat -u $SO2 $method:$server:$port,$addropts - ) & S2=$! case "$dir" in */) ftp_chat "NLST $dir" ;; #*/) ftp_chat "LIST $dir" ;; *) ftp_chat "RETR $dir" ;; esac case "$status" in [45]*) kill $S2;; esac #echo "waiting for process $S2 to terminate" >&2 wait $S2 ftp_chat ftp_chat "QUIT" #echo "waiting for process $S1 to terminate" >&2 wait $S1 exit