Add new tls-check util

1 files changed, 98 insertions, 0 deletions

diff --git a/.local/bin/tls-check b/.local/bin/tls-check
new file mode 100755
index 0000000..a38a8f1
--- /dev/null
+++ b/.local/bin/tls-check
@@ -0,0 +1,98 @@
+#!/bin/sh
+
+# This program is free software: you can redistribute it and/or modify it under
+# the terms of the GNU Affero General Public License as published by the Free
+# Software Foundation, either version 3 of the License, or (at your option) any
+# later version.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+# FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
+# details.
+
+readonly red=$(tput setaf 1)
+readonly green=$(tput setaf 2)
+readonly normal=$(tput sgr0)
+
+main()
+{
+	# Handle opts
+	while getopts ":hp:" opt
+	do
+		case "$opt" in
+			h) usage && exit 0 ;;
+			p) port=$OPTARG ;;
+			*)
+				printf "Invalid option passed: %s\n" "$OPTARG" >&2
+				;;
+		esac
+	done
+
+	shift $(( OPTIND - 1 ))
+
+	[ -z "$port" ] && port=443
+
+	# Show usage when no arguments are passed
+	if [ $# -lt 1 ]
+	then
+		usage && exit 0
+	fi
+
+	domain_length=0
+
+	# Calculate longest domain name
+	for domain in "$@"
+	do
+		if [ ${#domain} -gt $domain_length ]
+		then
+			domain_length=${#domain}
+		fi
+	done
+
+	# Print out TLS compatability matrix
+	for domain in "$@"
+	do
+		printf "%${domain_length}s:%d" "$domain" "$port"
+		printf "  %s${normal}" "$(openssl_tls_1_0 "$domain" && printf "%s" "${green}1.0" || printf "%s" "${red}1.0")"
+		printf "  %s${normal}" "$(openssl_tls_1_1 "$domain" && printf "%s" "${green}1.1" || printf "%s" "${red}1.1")"
+		printf "  %s${normal}" "$(openssl_tls_1_2 "$domain" && printf "%s" "${green}1.2" || printf "%s" "${red}1.2")"
+		printf "  %s${normal}" "$(openssl_tls_1_3 "$domain" && printf "%s" "${green}1.3" || printf "%s" "${red}1.3")"
+		printf "\n"
+	done
+}
+
+openssl_tls_1_0()
+{
+	printf "\n" | openssl s_client -tls1 -connect "$1:$port" > /dev/null 2>&1
+}
+
+openssl_tls_1_1()
+{
+	printf "\n" | openssl s_client -tls1_1 -connect "$1:$port" > /dev/null 2>&1
+}
+
+openssl_tls_1_2()
+{
+	printf "\n" | openssl s_client -tls1_2 -connect "$1:$port" > /dev/null 2>&1
+}
+
+openssl_tls_1_3()
+{
+	printf "\n" | openssl s_client -tls1_3 -connect "$1:$port" > /dev/null 2>&1
+}
+
+usage()
+{
+	cat <<EOF
+Usage:
+	${0##*/} -h
+
+Check a server for supported TLS versions.
+
+Options:
+	-h  Show this help text and exit.
+	-p  Set the port to test on. Defaults to 443.
+EOF
+}
+
+main "$@"