Hacking_and_Penetration_Testing_with_Low_Power_Devices

Adding tools the easy way
67
echo -n "Is the a Debian package or Source archive? [D]/S> "
read resp
if [ $resp ¼¼ 's' ] jj [ $resp ¼¼ 'S' ] ; then
echo "${pkg} ${url}" >> source-to-download.txt
else
echo "${pkg} ${url}" >> packages-to-download.txt
fi
fi
fi
}
# interate over the todo list
# read whole file into an array
declare -i count¼0
while read pkg
do
pkg_list[${count}]¼${pkg}
count+¼1
done < "todo-packages.txt"
# now call find_dpkg for each package
# note that we have to do this instead of the more straightforward
# method of reading in the values and calling find_dpkg directly
# because that would conflict with read statements in find_dpkg
for pkg in ${pkg_list[@]}
do
find_dpkg
done
The preceding script will create a file called packages-to-download.txt. Each line
in this file contains a package name, followed by a URL to download the required
Debian package file. The following script will iterate over this file and ask the user to
verify the URL before downloading. Once a file has been successfully downloaded,
it is sanity-checked to see if it is a .deb file. If it is not, the user is warned and given an
opportunity to enter an uncompress or rename command. Finally, the package is
installed using the command sudo dpkg -i /tmp/.
If you have been following along, there are only two new techniques used in this
script. The first is the use of the tr (translate) command. This is used twice in the
script: first to strip the filename from the end of the URL and then to strip the file
extension from the end of the filename.
Let us break down the first line where tr is used: fname¼$(echo $url j tr "/" "\n"
jtail-1). Recall that enclosing a command in $() causes the results of the command to
be assigned to a variable, fname in this case. The first command echo $url prints out
the URL and pipes it to the tr command. The command tr “/” “\n” causes every slash
to be replaced with a newline character. This effectively breaks each part of the URL
out onto a separate line. These lines are then piped to the tail-1 command that returns
only the last line, which is everything after the last /. Note that you need a direct