Cisco Anyconnect cscan compatibility for Arch Linux

rpm

#!/usr/bin/env bash
if [ "${1}" == "-q" ] && [[ ${2} == --qf* ]]; then
    arch="$(uname -m)"
    ver="$(pacman -Q ${@: -1} | awk '{print $2}')"
    if [ ! -z "${ver}" ]; then
        echo "{\"name\":\"${@: -1}\",\"version\":\"${ver}\",\"arch\":\"${arch}\"}"
    else
        echo "package ${@: -1} is not installed"
    fi
elif [ "${1}" == "-ql" ]; then
    pacman -Ql "${@: -1}" | awk '{print $2}'
else
    exit 1
fi

Horribly grubby (but working) script for Arch to get Cisco Anyconnect's hostscan to work properly on arch.

This script should be made executable and added to somewhere on the system PATH (not your local user!). I've stuck it in my home directory, and symlinked it to /bin/rpm.

cscan will call rpm -q --qf=\{"name":"%{NAME}","version":"%{VERSION}","arch":"%{ARCH}"\}, clamav and this will translate that into a valid json object for it to then parse:

❯ rpm -q --qf=\{"name":"%{NAME}","version":"%{VERSION}","arch":"%{ARCH}"\}, clamav
{"name":"clamav","version":"0.102.3-1","arch":"x86_64"}

Obviously this highlights the issue of trusting what some arbitrary command running on an uncontrolled system returns, as the calls to pacman could easily be replaced by just echoing out versions that cscan wants to see. But this at least attempts to be trustworthy.

Finally, some software uses grubby OS checking mechanisms and makes mandatory calls to rpm. I've tried to make this as non-affecting as possible, but the if on line 2 could be updated to be more specific so it only responds to the queries that cscan makes. I've seen this cause problems with, for example, dkms, however I have already handled this case.