ftp.sh

   1 #! /bin/sh
   2 # source: ftp.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 # example how to write a shell script that communicates with stdio on the front
   7 # end and with a socat address on the back end
   8
   9 # usage:
  10 # ftp.sh [opts] server directory/       # show directory contents on stdout
  11 # ftp.sh [opts] server file             # print file contents to stdout
  12 # opts:
  13 #       -socks socksserver      # use given socks server, port 1080
  14 #       -proxy proxyserver      # use given proxy server, port 8080
  15 #                               # must be http proxy that accepts CONNECT
  16 #                               # method to ports 21 and >=1024
  17 #       -user username          # default: "ftp"
  18 #       -passwd password        # default: "anonymous@domain.org"
  19 #       -t      # shell script trace+debug
  20 #       -d      # debug on control connection (use up to 4 times)
  21 #       -D      # debug on data connection (use up to 4 times)
  22 #       -b      # block size for data connection
  23 #       -v      # verbose
  24 #       -l*     # socat logging options
  25 # example:
  26 # ftp.sh -v -d -d -D -D -D -b 65536 -proxy proxy ftp.ftp.org /README >README
  27
  28 user="ftp"
  29 passwd="anonymous@domain.org"
  30 #method="socks4:socks"  # socks4 is address spec, socks is socks server name
  31 method=tcp
  32 addropts=
  33
  34 # socat options
  35 SO1=
  36 SO2=
  37
  38 while :; do
  39     case "$1" in
  40     -socks|-socks4) shift;
  41         case "$1" in
  42         *:*) method="socks4:${1%%:*}"; addropts="socksport=${1#*:}" ;;
  43         *) method="socks4:$1" ;;
  44         esac ;;
  45     -socks4a) shift;
  46         case "$1" in
  47         *:*) method="socks4a:${1%%:*}"; addropts="socksport=${1#*:}" ;;
  48         *) method="socks4a:$1" ;;
  49         esac ;;
  50     -proxy) shift;
  51         case "$1" in
  52         *:*) method="proxy:${1%%:*}"; addropts="proxyport=${1#*:}" ;;
  53         *) method="proxy:$1" ;;
  54         esac ;;
  55     -user) shift; user="$1" ;;
  56     -passwd) shift; passwd="$1" ;;
  57     -t) set -vx ;;
  58     -d) SO1="$SO1 -d" ;;
  59     -D) SO2="$SO2 -d" ;;
  60     -b) SO2="$SO2 -b $2"; shift ;;
  61     -v) SO1="$SO1 -v" ;;
  62     -l*) SO1="$SO1 $1"; SO2="$SO2 $1" ;;
  63     -*) echo "unknown option \"$1\"" >&2; exit 1;;
  64     *) break ;;
  65     esac
  66     shift
  67 done
  68 export SO2
  69
  70 server="$1"
  71 dir="$2"
  72
  73 echo "addr=$method:$server:21,$addropts"; exit
  74
  75 ### this is the central part to establish communication with socat ###
  76 ### copy these lines to make new communication shell scripts
  77 TMPDIR=$(if [ -x /bin/mktemp ]; then
  78             /bin/mktemp -d /tmp/$USER/FTPSH.XXXXXX
  79          else
  80             (umask 077; d=/tmp/$USER/FTPSH.$$; mkdir $d; echo $d)
  81          fi)
  82 TO="$TMPDIR/to"; FROM="$TMPDIR/from"
  83 socat $SO1 fifo:$TO,nonblock,ignoreeof!!fifo:$FROM $method:$server:21,$addropts &
  84 S1=$!
  85 while ! [ -p "$TO" -a -p "$FROM" ]; do sleep 1; done
  86 exec 4>$TMPDIR/to 3<$TMPDIR/from
  87 trap "S1=" 17
  88 #trap "echo cleaning up...>&2; rm -r $TMPDIR; [ -n "$S1" ] && kill $S1" 0 3
  89 trap "rm -r $TMPDIR" 0 3
  90 ### here the central part ends
  91
  92
  93 # this function waits for a complete server message, checks if its status
  94 # is in the permitted range (terminates session if not), and returns.
  95 ftp_chat () {
  96     local cmd="$1"
  97     local errlevel="$2";  [ -z "$errlevel" ] && errlevel=300
  98     if [ -n "$cmd" ]; then echo "$cmd" >&4; fi
  99     while read status message <&3;
 100        ( case "$status" in [0-9][0-9][0-9]-*) exit 0;; [0-9][0-9][0-9]*) exit 1;; *) exit 1;; esac )
 101     do :; done
 102     #echo "got \"$status $message\"" >&2
 103     if [ -z "$status" ]; then  echo ftp data connection failed >&2; exit;  fi
 104     if [ "$status" -ge "$errlevel" ]; then
 105         echo $message >&2
 106         echo "QUIT" >&4; exit 1
 107     fi
 108 set +vx
 109 }
 110
 111
 112 # wait for server greeting
 113 ftp_chat
 114
 115 ftp_chat "USER $user" 400
 116
 117 ftp_chat "PASS $passwd"
 118
 119 #ftp_chat "CWD $dir"
 120
 121 case "$dir" in
 122 */) ftp_chat "TYPE A" ;;
 123 *) ftp_chat "TYPE I" ;;
 124 esac
 125
 126 echo "PASV" >&4; read status message <&3
 127 info=$(expr "$message" : '.*[^0-9]\([0-9]*,[0-9]*,[0-9]*,[0-9]*,[0-9]*,[0-9]*\).*')
 128 echo $info |tr ',' ' ' |(read i1 i2 i3 i4 p1 p2
 129
 130     addr=$i1.$i2.$i3.$i4
 131     port=$(echo "256*$p1+$p2" |bc)
 132     #echo $addr:$port
 133
 134     trap : 20
 135     # open data connection and transfer data
 136     socat -u $SO2 $method:$server:$port,$addropts -
 137 ) &
 138 S2=$!
 139
 140 case "$dir" in
 141 */) ftp_chat "NLST $dir" ;;
 142 #*/) ftp_chat "LIST $dir" ;;
 143 *) ftp_chat "RETR $dir" ;;
 144 esac
 145 case "$status" in
 146     [45]*) kill $S2;;
 147 esac
 148
 149 #echo "waiting for process $S2 to terminate" >&2
 150 wait $S2
 151
 152 ftp_chat
 153
 154 ftp_chat "QUIT"
 155
 156 #echo "waiting for process $S1 to terminate" >&2
 157 wait $S1
 158 exit