From 58fef849d62b0381f1434aa5e1750ff590a0930a Mon Sep 17 00:00:00 2001
From: Phillip Kruger <phillip.kruger@gmail.com>
Date: Mon, 19 Aug 2024 19:07:32 +1000
Subject: [PATCH] DevUI: Allow regex for defined allowed hosts

Signed-off-by: Phillip Kruger <phillip.kruger@gmail.com>
---
 .../quarkus/devui/deployment/DevUIConfig.java |  1 +
 .../devui/runtime/LocalHostOnlyFilter.java    | 42 ++++++++++++++++++-
 2 files changed, 42 insertions(+), 1 deletion(-)

diff --git a/extensions/vertx-http/deployment/src/main/java/io/quarkus/devui/deployment/DevUIConfig.java b/extensions/vertx-http/deployment/src/main/java/io/quarkus/devui/deployment/DevUIConfig.java
index e5a2c5ab3acc3..c1dbfd9fc50b5 100644
--- a/extensions/vertx-http/deployment/src/main/java/io/quarkus/devui/deployment/DevUIConfig.java
+++ b/extensions/vertx-http/deployment/src/main/java/io/quarkus/devui/deployment/DevUIConfig.java
@@ -26,6 +26,7 @@ public class DevUIConfig {
      * More hosts allowed for Dev UI
      *
      * Comma separated list of valid URLs, e.g.: www.quarkus.io, myhost.com
+     * (This can also be a regex)
      * By default localhost and 127.0.0.1 will always be allowed
      */
     @ConfigItem
diff --git a/extensions/vertx-http/runtime/src/main/java/io/quarkus/devui/runtime/LocalHostOnlyFilter.java b/extensions/vertx-http/runtime/src/main/java/io/quarkus/devui/runtime/LocalHostOnlyFilter.java
index b5d0c9d50903b..a34c70222f271 100644
--- a/extensions/vertx-http/runtime/src/main/java/io/quarkus/devui/runtime/LocalHostOnlyFilter.java
+++ b/extensions/vertx-http/runtime/src/main/java/io/quarkus/devui/runtime/LocalHostOnlyFilter.java
@@ -4,7 +4,11 @@
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.net.URL;
+import java.util.ArrayList;
 import java.util.List;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+import java.util.regex.PatternSyntaxException;
 
 import org.jboss.logging.Logger;
 
@@ -19,9 +23,11 @@ public class LocalHostOnlyFilter implements Handler<RoutingContext> {
     private static final String LOCAL_HOST_IP = "127.0.0.1";
 
     private final List<String> hosts;
+    private final List<Pattern> hostsPatterns;
 
     public LocalHostOnlyFilter(List<String> hosts) {
         this.hosts = hosts;
+        this.hostsPatterns = detectPatterns();
     }
 
     @Override
@@ -45,11 +51,45 @@ private boolean hostIsValid(RoutingContext event) {
 
             if (host.equals(LOCAL_HOST) || host.equals(LOCAL_HOST_IP)) {
                 return true;
+            } else if (this.hosts != null && this.hosts.contains(host)) {
+                return true;
+            } else if (this.hostsPatterns != null && !this.hostsPatterns.isEmpty()) {
+                // Regex
+                for (Pattern pat : this.hostsPatterns) {
+                    Matcher matcher = pat.matcher(host);
+                    if (matcher.matches()) {
+                        return true;
+                    }
+                }
             }
-            return this.hosts != null && this.hosts.contains(host);
+            return false;
         } catch (MalformedURLException | URISyntaxException e) {
             LOG.error("Error while checking if Dev UI is localhost", e);
         }
         return false;
     }
+
+    private List<Pattern> detectPatterns() {
+        if (this.hosts != null && !this.hosts.isEmpty()) {
+            List<Pattern> pat = new ArrayList<>();
+            for (String h : this.hosts) {
+                Pattern p = toPattern(h);
+                if (p != null) {
+                    pat.add(p);
+                }
+            }
+            if (!pat.isEmpty()) {
+                return pat;
+            }
+        }
+        return null;
+    }
+
+    private Pattern toPattern(String regex) {
+        try {
+            return Pattern.compile(regex);
+        } catch (PatternSyntaxException e) {
+            return null;
+        }
+    }
 }