allow matching parts of hosts

pom.xml

@@ -31,6 +31,12 @@
 			<artifactId>slf4j-simple</artifactId>
 			<version>${slf4j-version}</version>
 		</dependency>
+		<dependency>
+			<groupId>org.junit.jupiter</groupId>
+			<artifactId>junit-jupiter-api</artifactId>
+			<version>5.10.2</version>
+			<scope>test</scope>
+		</dependency>
 	</dependencies>
 	<build>
 		<plugins>
@@ -42,6 +48,11 @@
 					<release>21</release>
 				</configuration>
 			</plugin>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-surefire-plugin</artifactId>
+				<version>3.2.2</version>
+			</plugin>
 			<plugin>
 				<groupId>org.apache.maven.plugins</groupId>
 				<artifactId>maven-assembly-plugin</artifactId>

src/main/java/io/github/danthe1st/httpsintercept/control/HostMatcher.java

@@ -0,0 +1,68 @@
+package io.github.danthe1st.httpsintercept.control;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+public class HostMatcher {
+	private Set<String> exactHosts = new HashSet<>();
+	private Set<String> hostParts = new HashSet<>();
+
+	public static HostMatcher load(Path config) throws IOException {
+		if(!Files.exists(config)){
+			Files.createFile(config);
+			return load(Collections.emptyList());
+		}
+		List<String> hostDeclarations = Files.readAllLines(config);
+		return load(hostDeclarations);
+	}
+
+	static HostMatcher load(List<String> hostDeclarations) {
+		Set<String> exactHosts = new HashSet<>();
+		Set<String> hostParts = new HashSet<>();
+		for(String ignored : hostDeclarations){
+			if(ignored.startsWith("*.")){
+				hostParts.add(ignored.substring(2));
+			}else{
+				exactHosts.add(ignored);
+			}
+		}
+		return new HostMatcher(exactHosts, hostParts);
+	}
+
+	HostMatcher(Set<String> exactHosts, Set<String> hostParts) {
+		this.exactHosts = Set.copyOf(exactHosts);
+		this.hostParts = Set.copyOf(hostParts);
+	}
+
+	public boolean matches(String hostname) {
+		return exactHosts.contains(hostname) || doesMatchPart(hostname);
+	}
+
+	private boolean doesMatchPart(String hostname) {
+		if(hostParts.isEmpty()){
+			return false;
+		}
+
+		int index = 0;
+		while((index = hostname.indexOf('.', index) + 1) != 0 && index < hostname.length()){
+			if(hostParts.contains(hostname.substring(index))){
+				return true;
+			}
+		}
+
+		return false;
+	}
+
+	Set<String> getExactHosts() {
+		return Collections.unmodifiableSet(exactHosts);
+	}
+
+	Set<String> getHostParts() {
+		return Collections.unmodifiableSet(hostParts);
+	}
+}

src/main/java/io/github/danthe1st/httpsintercept/handler/sni/CustomSniHandler.java

@@ -10,6 +10,7 @@
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
+import io.github.danthe1st.httpsintercept.control.HostMatcher;
 import io.github.danthe1st.httpsintercept.handler.raw.RawForwardIncomingRequestHandler;
 import io.netty.bootstrap.Bootstrap;
 import io.netty.channel.ChannelHandler;
@@ -27,13 +28,13 @@ public class CustomSniHandler extends SniHandler {
 
 	private final Bootstrap clientBootstrapTemplate;
 
-	private final Set<String> ignoredHosts;
+	private final HostMatcher ignoredHosts;
 
 	public CustomSniHandler(Mapping<? super String, ? extends SslContext> mapping, Bootstrap clientBootstrapTemplate) throws IOException {
 		super(mapping);
 		this.clientBootstrapTemplate = clientBootstrapTemplate;
 
-		ignoredHosts = loadIgnoredHosts();
+		ignoredHosts = HostMatcher.load(Path.of("ignoredHosts.txt"));
 	}
 
 	private static Set<String> loadIgnoredHosts() throws IOException {
@@ -50,8 +51,8 @@ private static Set<String> loadIgnoredHosts() throws IOException {
 	@Override
 	protected void replaceHandler(ChannelHandlerContext channelHandlerContext, String hostname, SslContext sslContext) throws Exception {
 		ChannelPipeline pipeline = channelHandlerContext.pipeline();
-		if(ignoredHosts.contains(hostname)){
-			LOG.debug("skipping hostname {}", hostname);
+		if(ignoredHosts.matches(hostname)){
+			LOG.info("skipping hostname {}", hostname);
 
 			boolean foundThis = false;
 

src/test/java/io/github/danthe1st/httpsintercept/control/HostMatcherTests.java

@@ -0,0 +1,59 @@
+package io.github.danthe1st.httpsintercept.control;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.util.Collections;
+import java.util.List;
+import java.util.Set;
+
+import org.junit.jupiter.api.Test;
+
+class HostMatcherTests {
+	@Test
+	void testExactMatch() {
+		HostMatcher matcher = new HostMatcher(Set.of("example.com"), Collections.emptySet());
+		assertTrue(matcher.matches("example.com"));
+		assertFalse(matcher.matches("github.com"));
+	}
+
+	@Test
+	void testPartMatch() {
+		HostMatcher matcher = new HostMatcher(Collections.emptySet(), Set.of("example.com"));
+		assertTrue(matcher.matches("host.example.com"));
+		assertTrue(matcher.matches(".example.com"));
+		assertFalse(matcher.matches("host.github.com"));
+		assertFalse(matcher.matches("example.com"));
+		assertFalse(matcher.matches("example.com."));
+		assertFalse(matcher.matches(""));
+		assertFalse(matcher.matches("."));
+	}
+
+	@Test
+	void testLoadExact() {
+		HostMatcher hostMatcher = HostMatcher.load(List.of("example.com"));
+		assertEquals(Set.of("example.com"), hostMatcher.getExactHosts());
+		assertEquals(Collections.emptySet(), hostMatcher.getHostParts());
+	}
+
+	@Test
+	void testLoadParts() {
+		HostMatcher hostMatcher = HostMatcher.load(List.of("*.example.com"));
+		assertEquals(Collections.emptySet(), hostMatcher.getExactHosts());
+		assertEquals(Set.of("example.com"), hostMatcher.getHostParts());
+
+		assertTrue(hostMatcher.matches("host.example.com"));
+	}
+
+	@Test
+	void testLoadEmptyPart() {
+		HostMatcher hostMatcher = HostMatcher.load(List.of("*."));
+		assertEquals(Collections.emptySet(), hostMatcher.getExactHosts());
+		assertEquals(Set.of(""), hostMatcher.getHostParts());
+
+		assertFalse(hostMatcher.matches("something"));
+		assertFalse(hostMatcher.matches("example.com"));
+	}
+
+}