csd-wrapper.sh

#!/bin/bash
# Cisco Anyconnect CSD wrapper for OpenConnect
#
# [05 May 2015] Written by Nikolay Panin <nick_panin@mail.ru>:
#   - source: https://gist.github.com/l0ki000/56845c00fd2a0e76d688
# [27 Oct 2017] Updated by Daniel Lenski <dlenski@gmail.com>:
#   - use -url argument
#   - kill cstub after timeout
#   - fix small typos:
# [31 May 2018] Updated by Daniel Lenski <dlenski@gmail.com>:
#   - use curl with --pinnedpubkey to rely on sha256 hash of peer cert passed by openconnect

TIMEOUT=30
URL="https://${CSD_HOSTNAME}/CACHE"
HOSTSCAN_DIR="$HOME/.cisco/hostscan"
LIB_DIR="$HOSTSCAN_DIR/lib"
BIN_DIR="$HOSTSCAN_DIR/bin"
PINNEDPUBKEY=${CSD_SHA256:+"--pinnedpubkey sha256//$CSD_SHA256"}

BINS=("cscan" "cstub" "cnotify")

# parsing command line
shift

URL=
TICKET=
STUB=
GROUP=
CERTHASH=
LANGSELEN=

while [ "$1" ]; do
    if [ "$1" == "-ticket" ];   then shift; TICKET=$1; fi
    if [ "$1" == "-stub" ];     then shift; STUB=$1; fi
    if [ "$1" == "-group" ];    then shift; GROUP=$1; fi
    if [ "$1" == "-certhash" ]; then shift; CERTHASH=$1; fi
    if [ "$1" == "-url" ];      then shift; URL=$(echo $1|tr -d '"'); fi # strip quotes
    if [ "$1" == "-langselen" ];then shift; LANGSELEN=$1; fi
    shift
done

ARCH=$(uname -m)

if [[ "$ARCH" == "x86_64" ]]
then
    ARCH="linux_x64"
else
    ARCH="linux_i386"
fi

# creating dirs
for dir in $HOSTSCAN_DIR $LIB_DIR $BIN_DIR ; do
    if [[ ! -f $dir ]]
    then
        mkdir -p $dir
    fi
done

# getting manifest, and checking binaries
curl $PINNEDPUBKEY "${URL}/sdesktop/hostscan/$ARCH/manifest" -o "$HOSTSCAN_DIR/manifest"

# generating md5.sum with full paths from manifest
export HOSTSCAN_DIR=$HOSTSCAN_DIR
cat $HOSTSCAN_DIR/manifest | sed -r 's/\(|\)//g' | awk '{ cmd = "find $HOSTSCAN_DIR -iname " $2; while (cmd | getline line) { print $4, line; } }' > $HOSTSCAN_DIR/md5.sum

# check number of files either
MD5_LINES=`wc --lines $HOSTSCAN_DIR/md5.sum | awk '{ print $1; }'`
MANIFEST_LINES=`wc --lines $HOSTSCAN_DIR/manifest | awk '{ print $1; }'`
echo "Got $MANIFEST_LINES files in manifest, locally found $MD5_LINES"

# check md5
md5sum -c $HOSTSCAN_DIR/md5.sum
if [[ "$?" -ne "0" || "$MD5_LINES" -ne "$MANIFEST_LINES" ]]
then
    echo "Corrupted files, or whatever wrong with md5 sums, or missing some file"
    # just download every file mentioned in manifest (not ideal, but hopefully should be enough)
    FILES=( $(cat $HOSTSCAN_DIR/manifest | sed -r 's/\(|\)//g' | awk '{ print $2; }') )
    WORK_DIR=`pwd`
    TMP_DIR=`mktemp -d` && cd $TMP_DIR
    for i in ${FILES[@]} ; do
        FILE="$(basename "$i")"

        echo "Downloading: $FILE to $TMP_DIR"
        curl $PINNEDPUBKEY "${URL}/sdesktop/hostscan/$ARCH/$FILE" -o $FILE

        # some files are in gz (don't understand logic here)
        if [[ ! -f $FILE || ! -s $FILE ]]
        then
            # remove 0 size files
            if [[ ! -s $FILE ]]; then
                rm $FILE
            fi

            echo "Failure on $FILE, trying gz"
            FILE_GZ=$FILE.gz
            curl $PINNEDPUBKEY "${URL}/sdesktop/hostscan/$ARCH/$FILE_GZ" -O $FILE_GZ
            gunzip --verbose --decompress $FILE_GZ
        fi

        # don't know why, but my version of hostscan requires tables to be stored in libs
        echo $FILE | grep --extended-regexp --quiet --invert-match ".so|tables.dat"
        IS_LIB=$?
        if [[ "$IS_LIB" -eq "1" ]]
        then
            cp --verbose $FILE $LIB_DIR
        else
            cp --verbose $FILE $BIN_DIR
        fi

    done

    for i in ${BINS[@]} ; do
        echo "Setting excecution bit on: $BIN_DIR/$i"
        chmod u+x $BIN_DIR/$i
    done

    cd $WORK_DIR
    rm -rf $TMP_DIR

fi

# cstub doesn't care about logging options, sic!
#ARGS="-log debug -ticket $TICKET -stub $STUB -group $GROUP -host "$URL" -certhash $CERTHASH"
ARGS="-log error -ticket $TICKET -stub $STUB -group $GROUP -host \"$URL\" -certhash $CERTHASH"

echo "Launching: $BIN_DIR/cstub $ARGS"
$BIN_DIR/cstub $ARGS & CSTUB_PID=$!

sleep $TIMEOUT
if kill -0 $CSTUB_PID 2> /dev/null; then
    echo "Killing cstub process after $TIMEOUT seconds"
    kill $CSTUB_PID 2> /dev/null || kill -9 $CSTUB_PID 2> /dev/null
fi