"Cherry-pick" (manually) some of the refactoring.

This commit is contained in:
Manuel Friedli 2020-08-03 13:32:32 +02:00
parent c5dc76f8eb
commit e46a378460

View file

@ -72,46 +72,40 @@ reset="\033[0m"
trap 'sudo -k; popd >/dev/null; rm -r ${tmpdir}' EXIT
function check_installed() {
local command="$1"
local package="$2"
which "${command}" 2>/dev/null >&2
local result=$?
local command="$1"
local package="$2"
which "${command}" 2>/dev/null >&2
local result=$?
if [[ "${result}" -ne 0 ]] ; then
echo -e "${red}Command ${bold}${command}${reset}${red} not found.${reset} Please install package ${blue}${package}${reset}."
exit 1
fi
if [[ "${result}" -ne 0 ]] ; then
echo -e "${red}Command ${bold}${command}${reset}${red} not found.${reset} Please install package ${blue}${package}${reset}."
exit 1
fi
}
# Create a temp directory, chdir into it and create the (initially empty)
# banlist file.
tmpdir=$(mktemp -d)
# Suppress output of dir stack.
pushd "${tmpdir}" > /dev/null
touch "${banlist}"
function print_help() {
cat <<ENDOFHELP
Usage: $(basename $0) [OPTION...]
-a, --auto[=LIMIT] Enable the autopilot for automatically banning chinese IP
addresses (whois output must contain "source: APNIC" and
"country: CN").
When LIMIT is given, only auto-ban IP addresses with at
least LIMIT current connections.
When LIMIT is omitted, assume LIMIT=1.
-a, --auto[=LIMIT] Enable the autopilot for automatically banning IP
addresses of the desired country (see also -c option).
When LIMIT is given, only auto-ban IP addresses with at
least LIMIT current connections.
When LIMIT is omitted, assume LIMIT=1.
-j, --jail=JAIL Specify the JAIL to use for banning the IP addresses. If
not set, uses 'apache-auth'.
-c, --country=COUNTRY The country-code to block; defaults to 'CN' (China).
-n, --netmask=SIZE SIZE defines the subnet size in bytes to be analyzed.
Valid values are:
- 1 or 8 for class A networks (X.0.0.0/8)
- 2 or 16 for class B networks (X.X.0.0/16)
- 3 or 24 for class C networks (X.X.X.0/24)
- 4 or 32 for class D networks (X.X.X.X/32)
-j, --jail=JAIL Specify the JAIL to use for banning the IP addresses.
Defaults to 'apache-auth'.
-h, --help Show this help message
-n, --netmask=SIZE SIZE defines the subnet size in bytes to be analyzed.
Valid values are:
- 1 or 8 for class A networks (X.0.0.0/8)
- 2 or 16 for class B networks (X.X.0.0/16)
- 3 or 24 for class C networks (X.X.X.0/24)
- 4 or 32 for class D networks (X.X.X.X/32)
-h, --help Show this help message
Mandatory or optional arguments to long options are also mandatory or optional
for any corresponding short options.
@ -129,8 +123,28 @@ function exec_as_root() {
fi
}
function filter() {
# list of current connections
file="$1"
# subnet extension, e.g. ".0.0/16"
ext="$2"
rm -f "${filtered}"
# Reject already banned addresses
while read -r -u3 address ; do
if [[ "${banned}" != *"${address}${ext}"* ]] ; then
echo "Considering ${address}."
echo "${address}" >> "${filtered}"
else
echo "IGNORING ${address}, already banned."
fi
done 3< "${file}"
mv "${filtered}" "${file}"
}
function parse_command_line_args() {
TEMP=$(getopt -o 'a::,j:,n:,h' -l 'auto::,jail:,netmask:,help' -- "$@")
TEMP=$(getopt -o 'a::,c:,j:,n:,h' -l 'auto::,country:,jail:,netmask:,help' -- "$@")
if [ $? -ne 0 ] ; then
echo 'Error parsing command line options. Terminating. Invoke with --help for help.' >&2
@ -157,6 +171,10 @@ function parse_command_line_args() {
esac
shift
;;
'-c'|'--country')
bancountry="$2"
shift
;;
'-j'|'--jail')
jail="$2"
shift
@ -199,10 +217,164 @@ function parse_command_line_args() {
done
}
################################################################################
# Set the highlighting color for the address count. The color goes from green
# (low count) over yellow (intermediate count) to red (high count). Depending
# on the size of the subnet (/8, /16, /24 or /32), the transitions from one
# color to the next happen at different values.
################################################################################
function set_highlight_color() {
local count=$1
case "${choice}" in
"1" )
# /32: 0 <= green < 3 <= yellow < 5 <= red
if [ $count -ge 5 ] ; then
hilite="${red}"
elif [ $count -ge 3 ] ; then
hilite="${yellow}"
else
hilite="${green}"
fi
;;
"2" )
# /24: 0 <= green < 7 <= yellow < 13 <= red
if [ $count -ge 13 ] ; then
hilite="${red}"
elif [ $count -ge 7 ] ; then
hilite="${yellow}"
else
hilite="${green}"
fi
;;
"3" )
# /16: 0 <= green < 13 <= yellow < 25 <= red
if [ $count -ge 25 ] ; then
hilite="${red}"
elif [ $count -ge 13 ] ; then
hilite="${yellow}"
else
hilite="${green}"
fi
;;
"4" )
# /8: 0 <= green < 21 <= yellow < 49 <= red
if [ $count -ge 49 ] ; then
hilite="${red}"
elif [ $count -ge 21 ] ; then
hilite="${yellow}"
else
hilite="${green}"
fi
;;
* )
# ???: We should never get here. As a fall-back, just use no
# highlighting.
hilite=""
;;
esac
}
################################################################################
# Process the file denoted by $1. For each line in the file, the count and the
# address are displayed and a whois request is made. The user can then choose to
# ban or ignore the address. Addresses chosen to be banned are appended to the
# $banlist.
################################################################################
function process_file () {
local file="${1}"
local line=''
local count=0
local addr=''
local banaction=''
local nline=1
local country_cn=1
# Read the contents from filedescriptor 3 (important: Don's use the
# standard filedescriptor because we need to handle user input from
# within the loop).
while IFS= read -r -u3 line ; do
line="$(echo "${line}" | tr -s '[:blank:]')"
count="$(echo "${line}" | cut -d' ' -f2)"
addr="$(echo "${line}" | cut -d' ' -f3-)${ext}"
set_highlight_color "${count}"
if [[ autopilot -eq 0 ]] ; then
whois "${addr}" | tee "${whoisoutput}"
else
whois "${addr}" > "${whoisoutput}"
fi
grep -iq "^country: *${bancountry}$" "${whoisoutput}"
country_cn=$?
echo -en "Address ${bold}$((nline++)) of ${nlines}${reset}: \
Found '${blue}${addr}${reset}' ${hilite}${count}${reset} times."
if [[ ${autopilot} -eq 0 ]] ; then
echo -en "Ban [y/N/s=No, and skip remaining]? "
read banaction
else
if [[ ${country_cn} -eq 0 ]] ; then
if [[ $count -ge $autopilot ]] ; then
echo -en "\n${red}Autopilot active. ${reset}"
banaction=y
else
echo -e "\n${yellow}Autopilot active. Ignoring remaining addresses due to limit of ${autopilot}.${reset}"
return
fi
else
if [[ $count -ge $autopilot ]] ; then
echo -en "\n${green}Autopilot active. ${reset}"
banaction=n
else
echo -e "\n${green}Autopilot active.${reset} ${yellow}Ignoring remaining addresses due to limit of ${autopilot}.${reset}"
return
fi
fi
fi
case "${banaction}" in
"s" | "S" )
echo -e "Not banning '${blue}${addr}${reset}', \
skipping remaining addresses."
return
;;
"y" | "Y" )
echo -e "Adding '${blue}${addr}${reset}' to \
banlist."
echo "${addr}" >> "${banlist}"
;;
"n" | "N" | * )
echo -e "Not banning '${blue}${addr}${reset}'."
;;
esac
# Here goes: Pipe the file contents via filedescriptor 3.
done 3< "${file}"
echo "Processed all entries in ${file}."
}
# Create a temp directory, chdir into it and create the (initially empty)
# banlist file.
tmpdir=$(mktemp -d)
# Suppress output of dir stack.
pushd "${tmpdir}" > /dev/null
touch "${banlist}"
check_installed "sudo" "app-admin/sudo"
check_installed "fail2ban-client" "net-analyzer/fail2ban"
check_installed "whois" "net-misc/whois"
check_installed "cut" "sys-apps/coreutils"
check_installed "id" "sys-apps/coreutils"
check_installed "sort" "sys-apps/coreutils"
check_installed "touch" "sys-apps/coreutils"
check_installed "tr" "sys-apps/coreutils"
check_installed "uniq" "sys-apps/coreutils"
check_installed "grep" "sys-apps/grep"
check_installed "sponge" "sys-apps/moreutils"
check_installed "netstat" "sys-apps/net_tools"
check_installed "getopt" "sys-apps/util-linux"
# Parse the command line options
autopilot=0
netmask=0
jail="apache-auth"
bancountry="CN"
parse_command_line_args "$@"
@ -220,26 +392,6 @@ cut -d. -f1-3 "${fileraw}" | sort > "${file24}"
cut -d. -f1-2 "${fileraw}" | sort > "${file16}"
cut -d. -f1 "${fileraw}" | sort > "${file8}"
function filter() {
# list of current connections
file="$1"
# subnet extension, e.g. ".0.0/16"
ext="$2"
rm -f "${filtered}"
# Reject already banned addresses
while read -r -u3 address ; do
if [[ "${banned}" != *"${address}${ext}"* ]] ; then
echo "Considering ${address}."
echo "${address}" >> "${filtered}"
else
echo "IGNORING ${address}, already banned."
fi
done 3< "${file}"
mv "${filtered}" "${file}"
}
# Filter already banned addresses
filter "${file32}" "${ext32}"
filter "${file24}" "${ext24}"
@ -305,143 +457,8 @@ unset TEMP
echo "Processing ${file}."
################################################################################
# Set the highlighting color for the address count. The color goes from green
# (low count) over yellow (intermediate count) to red (high count). Depending
# on the size of the subnet (/8, /16, /24 or /32), the transitions from one
# color to the next happen at different values.
################################################################################
function setHilite() {
local count=$1
case "${choice}" in
"1" )
# /32: 0 <= green < 3 <= yellow < 5 <= red
if [ $count -ge 5 ] ; then
hilite="${red}"
elif [ $count -ge 3 ] ; then
hilite="${yellow}"
else
hilite="${green}"
fi
;;
"2" )
# /24: 0 <= green < 7 <= yellow < 13 <= red
if [ $count -ge 13 ] ; then
hilite="${red}"
elif [ $count -ge 7 ] ; then
hilite="${yellow}"
else
hilite="${green}"
fi
;;
"3" )
# /16: 0 <= green < 13 <= yellow < 25 <= red
if [ $count -ge 25 ] ; then
hilite="${red}"
elif [ $count -ge 13 ] ; then
hilite="${yellow}"
else
hilite="${green}"
fi
;;
"4" )
# /8: 0 <= green < 21 <= yellow < 49 <= red
if [ $count -ge 49 ] ; then
hilite="${red}"
elif [ $count -ge 21 ] ; then
hilite="${yellow}"
else
hilite="${green}"
fi
;;
* )
# ???: We should never get here. As a fall-back, just use no
# highlighting.
hilite=""
;;
esac
}
################################################################################
# Process the file denoted by $1. For each line in the file, the count and the
# address are displayed and a whois request is made. The user can then choose to
# ban or ignore the address. Addresses chosen to be banned are appended to the
# $banlist.
################################################################################
function processFile () {
local file="${1}"
local line=''
local count=0
local addr=''
local banaction=''
local nline=1
local country_cn=1
local source_apnic=1
# Read the contents from filedescriptor 3 (important: Don's use the
# standard filedescriptor because we need to handle user input from
# within the loop).
while IFS= read -r -u3 line ; do
line="$(echo "${line}" | tr -s '[:blank:]')"
count="$(echo "${line}" | cut -d' ' -f2)"
addr="$(echo "${line}" | cut -d' ' -f3-)${ext}"
setHilite "${count}"
if [[ autopilot -eq 0 ]] ; then
whois "${addr}" | tee "${whoisoutput}"
else
whois "${addr}" > "${whoisoutput}"
fi
grep -iq "^country: *cn$" "${whoisoutput}"
country_cn=$?
grep -iq "^source: *apnic$" "${whoisoutput}"
source_apnic=$?
echo -en "Address ${bold}$((nline++)) of ${nlines}${reset}: \
Found '${blue}${addr}${reset}' ${hilite}${count}${reset} times."
if [[ ${autopilot} -eq 0 ]] ; then
echo -en "Ban [y/N/s=No, and skip remaining]? "
read banaction
else
if [[ ${country_cn} -eq 0 && ${source_apnic} -eq 0 ]] ; then
if [[ $count -ge $autopilot ]] ; then
echo -en "\n${red}Autopilot active. ${reset}"
banaction=y
else
echo -e "\n${yellow}Autopilot active. Ignoring remaining addresses due to limit of ${autopilot}.${reset}"
return
fi
else
if [[ $count -ge $autopilot ]] ; then
echo -en "\n${green}Autopilot active. ${reset}"
banaction=n
else
echo -e "\n${green}Autopilot active.${reset} ${yellow}Ignoring remaining addresses due to limit of ${autopilot}.${reset}"
return
fi
fi
fi
case "${banaction}" in
"s" | "S" )
echo -e "Not banning '${blue}${addr}${reset}', \
skipping remaining addresses."
return
;;
"y" | "Y" )
echo -e "Adding '${blue}${addr}${reset}' to \
banlist."
echo "${addr}" >> "${banlist}"
;;
"n" | "N" | * )
echo -e "Not banning '${blue}${addr}${reset}'."
;;
esac
# Here goes: Pipe the file contents via filedescriptor 3.
done 3< "${file}"
echo "Processed all entries in ${file}."
}
# Invoke the processing function on the chosen file.
processFile "${file}"
process_file "${file}"
echo "These are the addresses to be banned:"
cat "${banlist}"