Populates a pi-hole group with adlists from firebog

firebog.sh

#!/bin/bash

# This idempotent script populates a pi-hole group with adlists
# from firebog (https://v.firebog.net/hosts/lists.php)
#
# By default, 'nocross' is used, unless specified otherwise by the
# first argument (tick, nocross, all).
# The group is created and enabled automatically and each script
# invocation will update this group.

set -ou pipefail

MYTMP=$(mktemp -qd)
LIST=${MYTMP}/firebog.list

(( $# < 1 )) && set -- 'nocross'

log () {
	printf '%s\n' "$*" >&2
}

error() {
	log "$*"
	exit 1
}

cleanup() {
	# avoid rm -rf
	rm -f "${LIST}"
	rmdir --ignore-fail-on-non-empty "${MYTMP}"
}

validate() {
	zero_len() { printf '%u' 0; }

	# try http if https fails
	local header url
	url=$1

	if ! header=$(curl --silent --fail --head -- "${url}"); then
		log "!!URL IS INVALID!!: ${url}"
		zero_len
		return
	fi

	# connected but no valid header, shouldn't happen
	if [[ -z $header ]]; then
		log "!!NO VALID HEADER!!: ${url}"
	 	zero_len
		return
	fi

	# get the actual body size (http1.1/TE=chunked and http2 compatible)
	local len
	if ! len=$(curl --silent --fail --write-out '%{size_download}' -o /dev/null -- "${url}"); then
		# this should never happen
		log "!!NO VALID BODY!!: ${url}"
	 	zero_len
		return		
	fi

	# extract content-length, lines are \r\n terminated
	#local len=$(printf '%s' "${header}" | awk 'BEGIN {RS="\r\n";FS=": ";IGNORECASE=1};/^Content-Length/{print $2}')

	# no valid content-length
	if [[ -z $len || ! $len =~ ^[0-9]+$ ]]; then
		log "!!NO VALID CONTENT-LENGTH!!: ${1}"
		zero_len
		return
	fi

	# print content-length
	printf '%u' "${len}"
}

trap 'cleanup' EXIT

if ! curl --silent --fail --output "$LIST" -- "https://v.firebog.net/hosts/lists.php?type=${1}"; then
	error "Error downloading list."
fi

if [[ -s $LIST ]]; then
	# determine and wipe firebog group, firebog-{list}
	group_id=$(sqlite3 /etc/pihole/gravity.db "SELECT id FROM 'group' WHERE name LIKE 'firebog-${1}';")
	if [[ -z $group_id ]]; then
		error "Firebog group not found. Nothing changed."
	fi
	sudo sqlite3 /etc/pihole/gravity.db "DELETE FROM adlist WHERE id in ( SELECT adlist_id FROM adlist_by_group WHERE group_id = \"$group_id\" );"

	# create new default group entries
	while read -r url
	do
		len=$(validate "${url}")
		if (( len <= 0 )); then
			# try http fallback
			url=$(printf '%s' "${url}" | sed 's/^https/http/')
			log "!!HTTP FALLBACK!!: ${url}"
			len=$(validate "${url}")
			if (( len <= 0 )); then
				# still no luck, skip
				log "!!FALLBACK FAILED!!: skipping"
				continue
			fi
		fi
		printf "%s: (%u)\n" "${url}" "${len}"
		sudo sqlite3 /etc/pihole/gravity.db "INSERT OR IGNORE INTO adlist (address, comment, enabled) VALUES (\"${url}\", 'firebog-${1} (' || datetime('now','localtime') || ')', 1); UPDATE adlist_by_group SET group_id = \"$group_id\" WHERE adlist_id = last_insert_rowid();"
		unset entry
	done < "$LIST"
else
	error "List is empty."
fi

pihole restartdns reload-lists
#EOF