Added script to show certificate info (openssl is required).

bin/executable_show-cert.sh

@@ -0,0 +1,45 @@
+#!/bin/bash
+#
+# Show SSL Certificate info with openssl.
+# Inspired by https://cheat.sh/openssl
+#
+
+function show-cert() {
+    local host=$1
+    local port=${2:-443}
+    local type=${3:short}
+
+    echo "Certificate info for $host:$port"
+    echo
+    if [ "$type" == "pem" ]; then
+        echo | openssl s_client -connect "$host:$port" 2> /dev/null | \
+            awk '/-----BEGIN/,/END CERTIFICATE-----/'
+    else
+        echo | openssl s_client -connect "$host:$port" 2> /dev/null | \
+            awk '/-----BEGIN/,/END CERTIFICATE-----/' | \
+            openssl x509 -noout -subject -dates
+    fi
+}
+
+if [ $# -lt 1 ]; then
+    echo "Usage: $0 <option> host <port>"
+    echo
+    echo "    host:     hostname to get Certificate"
+    echo "    port:     optional port (default is 443)"
+    echo "    options:  "
+    echo "          -v  verbose, print certificate (PEM format)"
+    exit 42
+fi
+
+while getopts "v" opt; do
+    case $opt in
+        v)
+            shift
+            type=pem
+            ;;
+        *)
+            ;;
+    esac
+done
+
+show-cert "$1" "$2" "$type"