CVE-2016-4993

@@ -155,6 +155,13 @@ public State encode(HeaderMap headers, ByteBuffer target) {
                     int required = 11 + headerName.length(); //we use 11 to make sure we have enough room for the variable length itegers
 
                     String val = values.get(i);
+                    for(int v = 0; v < val.length(); ++v) {
+                        char c = val.charAt(v);
+                        if(c == '\r' || c == '\n') {
+                            val = val.replace('\r', ' ').replace('\n', ' ');
+                            break;
+                        }
+                    }
                     TableEntry tableEntry = findInTable(headerName, val);
 
                     required += (1 + val.length());

@@ -151,7 +151,12 @@ private static void putString(final ByteBuffer buf, String value) {
         final int length = value.length();
         putInt(buf, length);
         for (int i = 0; i < length; ++i) {
-            buf.put((byte) value.charAt(i));
+            char c = value.charAt(i);
+            if(c != '\r' && c != '\n'){
+                buf.put((byte) c);
+            } else {
+                buf.put((byte)' ');
+            }
         }
         buf.put((byte) 0);
     }

@@ -289,7 +289,12 @@ private void bufferDone() {
     private static void writeString(ByteBuffer buffer, String string) {
         int length = string.length();
         for (int charIndex = 0; charIndex < length; charIndex++) {
-            buffer.put((byte) string.charAt(charIndex));
+            char c = string.charAt(charIndex);
+            if(c != '\r' && c != '\n') {
+                buffer.put((byte) c);
+            } else {
+                buffer.put((byte) ' ');
+            }
         }
     }
 

@@ -476,6 +476,10 @@ public interface UndertowMessages {
     @Message(id = 148, value = "Invalid HPack encoding. First byte: %s")
     HpackException invalidHpackEncoding(byte b);
 
-    @Message(id = 149, value = "Pseudo header %s received after receiving normal headers. Pseudo headers must be the first headers in a HTTP/2 header block.")
+    @Message(id = 149, value = "HttpString is not allowed to contain newlines. value: %s")
+    IllegalArgumentException newlineNotSupportedInHttpString(String value);
+
+    @Message(id = 150, value = "Pseudo header %s received after receiving normal headers. Pseudo headers must be the first headers in a HTTP/2 header block.")
     IllegalArgumentException pseudoHeaderInWrongOrder(HttpString header);
+
 }

@@ -30,6 +30,8 @@
 import static java.lang.System.arraycopy;
 import static java.util.Arrays.copyOfRange;
 
+import io.undertow.UndertowMessages;
+
 /**
  * An HTTP case-insensitive Latin-1 string.
  *
@@ -116,13 +118,23 @@ public HttpString(final String string) {
         this.bytes = bytes;
         this.hashCode = calcHashCode(bytes);
         this.string = string;
+        checkForNewlines();
+    }
+
+    private void checkForNewlines() {
+        for(byte b : bytes) {
+            if(b == '\r' || b == '\n') {
+                throw UndertowMessages.MESSAGES.newlineNotSupportedInHttpString(string);
+            }
+        }
     }
 
     private HttpString(final byte[] bytes, final String string) {
         this.bytes = bytes;
         this.hashCode = calcHashCode(bytes);
         this.string = string;
         this.orderInt = 0;
+        checkForNewlines();
     }
 
     /**

@@ -0,0 +1,78 @@
+/*
+ * JBoss, Home of Professional Open Source.
+ * Copyright 2014 Red Hat, Inc., and individual contributors
+ * as indicated by the @author tags.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package io.undertow.server;
+
+import java.io.IOException;
+
+import org.apache.http.HttpResponse;
+import org.apache.http.client.methods.HttpPost;
+import org.apache.http.entity.StringEntity;
+import org.junit.Assert;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import io.undertow.io.Receiver;
+import io.undertow.testutils.DefaultServer;
+import io.undertow.testutils.HttpClientUtils;
+import io.undertow.testutils.TestHttpClient;
+import io.undertow.util.HttpString;
+import io.undertow.util.StatusCodes;
+
+/**
+ * @author Stuart Douglas
+ */
+@RunWith(DefaultServer.class)
+public class NewlineInHeadersTestCase {
+
+    private static final String RESPONSE = "response";
+    private static final String ECHO = "echo";
+
+    @Test
+    public void testNewlineInHeaders() throws IOException {
+        DefaultServer.setRootHandler(new HttpHandler() {
+            @Override
+            public void handleRequest(HttpServerExchange exchange) throws Exception {
+                exchange.getRequestReceiver().receiveFullString(new Receiver.FullStringCallback() {
+                    @Override
+                    public void handle(HttpServerExchange exchange, String message) {
+                        exchange.getResponseHeaders().put(HttpString.tryFromString(ECHO), message);
+                        exchange.getResponseSender().send(RESPONSE);
+                    }
+                });
+            }
+        });
+        final TestHttpClient client = new TestHttpClient();
+        try {
+            HttpPost post = new HttpPost(DefaultServer.getDefaultServerURL());
+            post.setEntity(new StringEntity("test"));
+            HttpResponse result = client.execute(post);
+            Assert.assertEquals(StatusCodes.OK, result.getStatusLine().getStatusCode());
+            Assert.assertEquals("test", result.getFirstHeader(ECHO).getValue());
+            Assert.assertEquals(RESPONSE, HttpClientUtils.readResponse(result));
+
+            post = new HttpPost(DefaultServer.getDefaultServerURL());
+            post.setEntity(new StringEntity("test\nnewline"));
+            result = client.execute(post);
+            Assert.assertEquals(StatusCodes.OK, result.getStatusLine().getStatusCode());
+            Assert.assertEquals("test newline", result.getFirstHeader(ECHO).getValue());
+            Assert.assertEquals(RESPONSE, HttpClientUtils.readResponse(result));
+        } finally {
+            client.getConnectionManager().shutdown();
+        }
+    }
+}