haraka-env-var-config.patch

diff --git a/configfile.js b/configfile.js
index 59d2ad0..2c1ca8f 100644
--- a/configfile.js
+++ b/configfile.js
@@ -91,6 +91,31 @@ function getStubLogger () {
     }
 }
 
+function env_var_replace(value) {
+    if (typeof value !== 'string') {
+        return value;
+    }
+	// replace $NAME with environment variable NAME (or $$ with $)
+	return value.replace(/(\$\$)|\$(\w+)|\$\{([^}]+)\}/g, (match, p1, p2, p3) => {
+        var default_value = '';
+        if (p3) {
+            // support default values in the form ${NAME:-default}
+            const is_assignment = /:=/.test(p3);
+            const name_default = p3.split(/:[-=]/);
+            if (name_default.length === 2) {
+                p3 = name_default[0];
+                default_value = name_default[1];
+                if (is_assignment && p3 && !process.env[p3]) {
+                    process.env[p3] = default_value;
+                }
+            }
+        }
+        var replacement = p1 ? '$' : (process.env[p2 || p3 || ''] || default_value);
+        return replacement;
+    });
+}
+cfreader.env_var_replace = env_var_replace;
+
 cfreader.on_watch_event = function (name, type, options, cb) {
     return function (fse, filename) {
         if (cfreader._sedation_timers[name]) {
@@ -504,6 +529,7 @@ cfreader.load_ini_config = function (name, options) {
             pre = '';
             match = regex.param.exec(line);
             if (match) {
+                match[2] = env_var_replace(match[2]);
                 is_array_match = regex.is_array.exec(match[1]);
                 if (is_array_match){
                     setter = function (key, value) {
@@ -562,7 +588,7 @@ cfreader.load_flat_config = function (name, type) {
             if (type === 'data') {
                 while (data.length > 0) {
                     var match = data.match(/^([^\r\n]*)\r?\n?/);
-                    result.push(match[1]);
+                    result.push(env_var_replace(match[1]));
                     data = data.slice(match[0].length);
                 }
                 return result;
@@ -579,7 +605,7 @@ cfreader.load_flat_config = function (name, type) {
                 }
                 line_data = regex.line.exec(line);
                 if (line_data) {
-                    result.push(line_data[1].trim());
+                    result.push(env_var_replace(line_data[1].trim()));
                 }
             });
         }
diff --git a/plugins/tls.js b/plugins/tls.js
index 752c478..c2600f3 100644
--- a/plugins/tls.js
+++ b/plugins/tls.js
@@ -3,6 +3,7 @@
 // see 'haraka -h tls' for help
 
 var tls_socket = require('./tls_socket');
+var { env_var_replace } = require('../configfile');
 
 // exported so tests can override config dir
 exports.net_utils = require('haraka-net-utils');
@@ -67,14 +68,14 @@ exports.load_tls_ini = function () {
     for (let i = 0; i < config_options.length; i++) {
         let opt = config_options[i];
         if (plugin.cfg.main[opt] === undefined) continue;
-        plugin.tls_opts[opt] = plugin.cfg.main[opt];
+        plugin.tls_opts[opt] = env_var_replace(plugin.cfg.main[opt]);
     }
 
     if (plugin.cfg.inbound) {
         for (let i = 0; i < config_options.length; i++) {
             let opt = config_options[i];
             if (plugin.cfg.inbound[opt] === undefined) continue;
-            plugin.tls_opts[opt] = plugin.cfg.inbound[opt];
+            plugin.tls_opts[opt] = env_var_replace(plugin.cfg.inbound[opt]);
         }
     }
 }