Make raw User-Agent strings available to gRPC services

service/src/main/java/org/whispersystems/textsecuregcm/grpc/RequestAttributesInterceptor.java

@@ -59,6 +59,15 @@ public class RequestAttributesInterceptor implements ServerInterceptor {
         }
       }
 
+      {
+        final Optional<String> maybeRawUserAgent =
+            grpcClientConnectionManager.getRawUserAgent(localAddress);
+
+        if (maybeRawUserAgent.isPresent()) {
+          context = context.withValue(RequestAttributesUtil.RAW_USER_AGENT_CONTEXT_KEY, maybeRawUserAgent.get());
+        }
+      }
+
       {
         final Optional<UserAgent> maybeUserAgent = grpcClientConnectionManager.getUserAgent(localAddress);
 

service/src/main/java/org/whispersystems/textsecuregcm/grpc/RequestAttributesUtil.java

@@ -13,7 +13,8 @@ public class RequestAttributesUtil {
 
   static final Context.Key<List<Locale.LanguageRange>> ACCEPT_LANGUAGE_CONTEXT_KEY = Context.key("accept-language");
   static final Context.Key<InetAddress> REMOTE_ADDRESS_CONTEXT_KEY = Context.key("remote-address");
-  static final Context.Key<UserAgent> USER_AGENT_CONTEXT_KEY = Context.key("user-agent");
+  static final Context.Key<String> RAW_USER_AGENT_CONTEXT_KEY = Context.key("unparsed-user-agent");
+  static final Context.Key<UserAgent> USER_AGENT_CONTEXT_KEY = Context.key("parsed-user-agent");
 
   private static final List<Locale> AVAILABLE_LOCALES = Arrays.asList(Locale.getAvailableLocales());
 
@@ -51,9 +52,18 @@ public class RequestAttributesUtil {
   /**
    * Returns the parsed user-agent of the remote client in the current gRPC request context.
    *
-   * @return the parsed user-agent of the remote client; may be null if unparseable or not specified
+   * @return the parsed user-agent of the remote client; may be empty if unparseable or not specified
    */
   public static Optional<UserAgent> getUserAgent() {
     return Optional.ofNullable(USER_AGENT_CONTEXT_KEY.get());
   }
+
+  /**
+   * Returns the unparsed user-agent of the remote client in the current gRPC request context.
+   *
+   * @return the unparsed user-agent of the remote client; may be empty if not specified
+   */
+  public static Optional<String> getRawUserAgent() {
+    return Optional.ofNullable(RAW_USER_AGENT_CONTEXT_KEY.get());
+  }
 }

service/src/main/java/org/whispersystems/textsecuregcm/grpc/net/GrpcClientConnectionManager.java

@@ -106,7 +106,21 @@ public class GrpcClientConnectionManager implements DisconnectionRequestListener
   }
 
   /**
-   * Returns the parsed user agent provided by the client the opened the connection associated with the given local
+   * Returns the unparsed user agent provided by the client that opened the connection associated with the given local
+   * address. This method may return an empty value if no active local connection is associated with the given local
+   * address.
+   *
+   * @param localAddress the local address for which to find a User-Agent string
+   *
+   * @return the user agent string associated with the given local address
+   */
+  public Optional<String> getRawUserAgent(final LocalAddress localAddress) {
+    return Optional.ofNullable(remoteChannelsByLocalAddress.get(localAddress))
+        .map(remoteChannel -> remoteChannel.attr(RAW_USER_AGENT_ATTRIBUTE_KEY).get());
+  }
+
+  /**
+   * Returns the parsed user agent provided by the client that opened the connection associated with the given local
    * address. This method may return an empty value if no active local connection is associated with the given local
    * address or if the client's user-agent string was not recognized.
    *

service/src/test/java/org/whispersystems/textsecuregcm/grpc/RequestAttributesServiceImpl.java

@@ -33,6 +33,8 @@ public class RequestAttributesServiceImpl extends RequestAttributesGrpc.RequestA
             .setAdditionalSpecifiers(userAgent.getAdditionalSpecifiers().orElse(""))
         .build()));
 
+    RequestAttributesUtil.getRawUserAgent().ifPresent(responseBuilder::setRawUserAgent);
+
     responseObserver.onNext(responseBuilder.build());
     responseObserver.onCompleted();
   }

service/src/test/java/org/whispersystems/textsecuregcm/grpc/RequestAttributesUtilTest.java

@@ -152,6 +152,21 @@ class RequestAttributesUtilTest {
     assertEquals("Linux", response.getUserAgent().getAdditionalSpecifiers());
   }
 
+  @Test
+  void getRawUserAgent() {
+    when(grpcClientConnectionManager.getRawUserAgent(any()))
+        .thenReturn(Optional.empty());
+
+    assertTrue(getRequestAttributes().getRawUserAgent().isBlank());
+
+    final String userAgentString = "Signal-Desktop/1.2.3 Linux";
+
+    when(grpcClientConnectionManager.getRawUserAgent(any()))
+        .thenReturn(Optional.of(userAgentString));
+
+    assertEquals(userAgentString, getRequestAttributes().getRawUserAgent());
+  }
+
   private GetRequestAttributesResponse getRequestAttributes() {
     return RequestAttributesGrpc.newBlockingStub(managedChannel)
         .getRequestAttributes(GetRequestAttributesRequest.newBuilder().build());

service/src/test/proto/request_attributes_service.proto

@@ -23,7 +23,8 @@ message GetRequestAttributesResponse {
   repeated string acceptable_languages = 1;
   repeated string available_accepted_locales = 2;
   string remote_address = 3;
-  UserAgent user_agent = 4;
+  string raw_user_agent = 4;
+  UserAgent user_agent = 5;
 }
 
 message UserAgent {