Support for ephemeral provisioning communication channels.

// FREEBIE

protobuf/OutgoingMessageSignal.proto

@@ -1,5 +1,5 @@
 /**
- * Copyright (C) 2013 Open WhisperSystems
+ * Copyright (C) 2013 - 2015 Open WhisperSystems
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as published by
@@ -37,3 +37,7 @@ message OutgoingMessageSignal {
   optional uint64 timestamp = 5;
   optional bytes message = 6;
 }
+
+message ProvisioningUuid {
+  optional string uuid = 1;
+}

src/main/java/org/whispersystems/textsecuregcm/WhisperServerService.java

@@ -47,7 +47,6 @@ import org.whispersystems.textsecuregcm.mappers.IOExceptionMapper;
 import org.whispersystems.textsecuregcm.mappers.RateLimitExceededExceptionMapper;
 import org.whispersystems.textsecuregcm.metrics.CpuUsageGauge;
 import org.whispersystems.textsecuregcm.metrics.FreeMemoryGauge;
-import org.whispersystems.textsecuregcm.metrics.JsonMetricsReporter;
 import org.whispersystems.textsecuregcm.metrics.NetworkReceivedGauge;
 import org.whispersystems.textsecuregcm.metrics.NetworkSentGauge;
 import org.whispersystems.textsecuregcm.providers.MemcacheHealthCheck;
@@ -75,7 +74,8 @@ import org.whispersystems.textsecuregcm.storage.PubSubManager;
 import org.whispersystems.textsecuregcm.storage.StoredMessages;
 import org.whispersystems.textsecuregcm.util.Constants;
 import org.whispersystems.textsecuregcm.util.UrlSigner;
-import org.whispersystems.textsecuregcm.websocket.ConnectListener;
+import org.whispersystems.textsecuregcm.websocket.AuthenticatedConnectListener;
+import org.whispersystems.textsecuregcm.websocket.ProvisioningConnectListener;
 import org.whispersystems.textsecuregcm.websocket.WebSocketAccountAuthenticator;
 import org.whispersystems.textsecuregcm.workers.DirectoryCommand;
 import org.whispersystems.textsecuregcm.workers.VacuumCommand;
@@ -190,15 +190,27 @@ public class WhisperServerService extends Application<WhisperServerConfiguration
     if (config.getWebsocketConfiguration().isEnabled()) {
       WebSocketEnvironment webSocketEnvironment = new WebSocketEnvironment(environment, config);
       webSocketEnvironment.setAuthenticator(new WebSocketAccountAuthenticator(deviceAuthenticator));
-      webSocketEnvironment.setConnectListener(new ConnectListener(accountsManager, pushSender, storedMessages, pubSubManager));
+      webSocketEnvironment.setConnectListener(new AuthenticatedConnectListener(accountsManager, pushSender, storedMessages, pubSubManager));
       webSocketEnvironment.jersey().register(new KeepAliveController());
 
-      WebSocketResourceProviderFactory servlet = new WebSocketResourceProviderFactory(webSocketEnvironment);
+      WebSocketEnvironment provisioningEnvironment = new WebSocketEnvironment(environment, config);
+      provisioningEnvironment.setConnectListener(new ProvisioningConnectListener(pubSubManager));
+      provisioningEnvironment.jersey().register(new KeepAliveController());
+      
+      WebSocketResourceProviderFactory webSocketServlet    = new WebSocketResourceProviderFactory(webSocketEnvironment   );
+      WebSocketResourceProviderFactory provisioningServlet = new WebSocketResourceProviderFactory(provisioningEnvironment);
+
+      ServletRegistration.Dynamic websocket    = environment.servlets().addServlet("WebSocket", webSocketServlet      );
+      ServletRegistration.Dynamic provisioning = environment.servlets().addServlet("Provisioning", provisioningServlet);
 
-      ServletRegistration.Dynamic websocket = environment.servlets().addServlet("WebSocket", servlet);
       websocket.addMapping("/v1/websocket/*");
       websocket.setAsyncSupported(true);
-      servlet.start();
+
+      provisioning.addMapping("/v1/provisioning/*");
+      provisioning.setAsyncSupported(true);
+
+      webSocketServlet.start();
+      provisioningServlet.start();
 
       FilterRegistration.Dynamic filter = environment.servlets().addFilter("CORS", CrossOriginFilter.class);
       filter.addMappingForUrlPatterns(EnumSet.allOf(DispatcherType.class), true, "/*");

src/main/java/org/whispersystems/textsecuregcm/controllers/MessageController.java

@@ -26,6 +26,7 @@ import org.whispersystems.textsecuregcm.entities.IncomingMessageList;
 import org.whispersystems.textsecuregcm.entities.MessageProtos.OutgoingMessageSignal;
 import org.whispersystems.textsecuregcm.entities.MessageResponse;
 import org.whispersystems.textsecuregcm.entities.MismatchedDevices;
+import org.whispersystems.textsecuregcm.entities.ProvisioningMessage;
 import org.whispersystems.textsecuregcm.entities.StaleDevices;
 import org.whispersystems.textsecuregcm.federation.FederatedClient;
 import org.whispersystems.textsecuregcm.federation.FederatedClientManager;
@@ -38,6 +39,8 @@ import org.whispersystems.textsecuregcm.storage.Account;
 import org.whispersystems.textsecuregcm.storage.AccountsManager;
 import org.whispersystems.textsecuregcm.storage.Device;
 import org.whispersystems.textsecuregcm.util.Base64;
+import org.whispersystems.textsecuregcm.websocket.InvalidWebsocketAddressException;
+import org.whispersystems.textsecuregcm.websocket.ProvisioningAddress;
 
 import javax.validation.Valid;
 import javax.ws.rs.Consumes;
@@ -128,6 +131,21 @@ public class MessageController {
     }
   }
 
+  @Timed
+  @PUT
+  @Path("/provisioning/{destination}")
+  @Consumes(MediaType.APPLICATION_JSON)
+  public void sendProvisioningMessage(@Auth                     Account source,
+                                      @PathParam("destination") String destinationName,
+                                      @Valid                    ProvisioningMessage message)
+      throws RateLimitExceededException, InvalidWebsocketAddressException
+  {
+    rateLimiters.getMessagesLimiter().validate(source.getNumber());
+
+    pushSender.getWebSocketSender().sendProvisioningMessage(new ProvisioningAddress(destinationName),
+                                                            message.getBody());
+  }
+
   private void sendLocalMessage(Account source,
                                 String destinationName,
                                 IncomingMessageList messages)

src/main/java/org/whispersystems/textsecuregcm/entities/MessageProtos.java

@@ -1112,11 +1112,487 @@ public final class MessageProtos {
     // @@protoc_insertion_point(class_scope:textsecure.OutgoingMessageSignal)
   }
 
+  public interface ProvisioningUuidOrBuilder
+      extends com.google.protobuf.MessageOrBuilder {
+
+    // optional string uuid = 1;
+    /**
+     * <code>optional string uuid = 1;</code>
+     */
+    boolean hasUuid();
+    /**
+     * <code>optional string uuid = 1;</code>
+     */
+    java.lang.String getUuid();
+    /**
+     * <code>optional string uuid = 1;</code>
+     */
+    com.google.protobuf.ByteString
+        getUuidBytes();
+  }
+  /**
+   * Protobuf type {@code textsecure.ProvisioningUuid}
+   */
+  public static final class ProvisioningUuid extends
+      com.google.protobuf.GeneratedMessage
+      implements ProvisioningUuidOrBuilder {
+    // Use ProvisioningUuid.newBuilder() to construct.
+    private ProvisioningUuid(com.google.protobuf.GeneratedMessage.Builder<?> builder) {
+      super(builder);
+      this.unknownFields = builder.getUnknownFields();
+    }
+    private ProvisioningUuid(boolean noInit) { this.unknownFields = com.google.protobuf.UnknownFieldSet.getDefaultInstance(); }
+
+    private static final ProvisioningUuid defaultInstance;
+    public static ProvisioningUuid getDefaultInstance() {
+      return defaultInstance;
+    }
+
+    public ProvisioningUuid getDefaultInstanceForType() {
+      return defaultInstance;
+    }
+
+    private final com.google.protobuf.UnknownFieldSet unknownFields;
+    @java.lang.Override
+    public final com.google.protobuf.UnknownFieldSet
+        getUnknownFields() {
+      return this.unknownFields;
+    }
+    private ProvisioningUuid(
+        com.google.protobuf.CodedInputStream input,
+        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
+        throws com.google.protobuf.InvalidProtocolBufferException {
+      initFields();
+      int mutable_bitField0_ = 0;
+      com.google.protobuf.UnknownFieldSet.Builder unknownFields =
+          com.google.protobuf.UnknownFieldSet.newBuilder();
+      try {
+        boolean done = false;
+        while (!done) {
+          int tag = input.readTag();
+          switch (tag) {
+            case 0:
+              done = true;
+              break;
+            default: {
+              if (!parseUnknownField(input, unknownFields,
+                                     extensionRegistry, tag)) {
+                done = true;
+              }
+              break;
+            }
+            case 10: {
+              bitField0_ |= 0x00000001;
+              uuid_ = input.readBytes();
+              break;
+            }
+          }
+        }
+      } catch (com.google.protobuf.InvalidProtocolBufferException e) {
+        throw e.setUnfinishedMessage(this);
+      } catch (java.io.IOException e) {
+        throw new com.google.protobuf.InvalidProtocolBufferException(
+            e.getMessage()).setUnfinishedMessage(this);
+      } finally {
+        this.unknownFields = unknownFields.build();
+        makeExtensionsImmutable();
+      }
+    }
+    public static final com.google.protobuf.Descriptors.Descriptor
+        getDescriptor() {
+      return org.whispersystems.textsecuregcm.entities.MessageProtos.internal_static_textsecure_ProvisioningUuid_descriptor;
+    }
+
+    protected com.google.protobuf.GeneratedMessage.FieldAccessorTable
+        internalGetFieldAccessorTable() {
+      return org.whispersystems.textsecuregcm.entities.MessageProtos.internal_static_textsecure_ProvisioningUuid_fieldAccessorTable
+          .ensureFieldAccessorsInitialized(
+              org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid.class, org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid.Builder.class);
+    }
+
+    public static com.google.protobuf.Parser<ProvisioningUuid> PARSER =
+        new com.google.protobuf.AbstractParser<ProvisioningUuid>() {
+      public ProvisioningUuid parsePartialFrom(
+          com.google.protobuf.CodedInputStream input,
+          com.google.protobuf.ExtensionRegistryLite extensionRegistry)
+          throws com.google.protobuf.InvalidProtocolBufferException {
+        return new ProvisioningUuid(input, extensionRegistry);
+      }
+    };
+
+    @java.lang.Override
+    public com.google.protobuf.Parser<ProvisioningUuid> getParserForType() {
+      return PARSER;
+    }
+
+    private int bitField0_;
+    // optional string uuid = 1;
+    public static final int UUID_FIELD_NUMBER = 1;
+    private java.lang.Object uuid_;
+    /**
+     * <code>optional string uuid = 1;</code>
+     */
+    public boolean hasUuid() {
+      return ((bitField0_ & 0x00000001) == 0x00000001);
+    }
+    /**
+     * <code>optional string uuid = 1;</code>
+     */
+    public java.lang.String getUuid() {
+      java.lang.Object ref = uuid_;
+      if (ref instanceof java.lang.String) {
+        return (java.lang.String) ref;
+      } else {
+        com.google.protobuf.ByteString bs = 
+            (com.google.protobuf.ByteString) ref;
+        java.lang.String s = bs.toStringUtf8();
+        if (bs.isValidUtf8()) {
+          uuid_ = s;
+        }
+        return s;
+      }
+    }
+    /**
+     * <code>optional string uuid = 1;</code>
+     */
+    public com.google.protobuf.ByteString
+        getUuidBytes() {
+      java.lang.Object ref = uuid_;
+      if (ref instanceof java.lang.String) {
+        com.google.protobuf.ByteString b = 
+            com.google.protobuf.ByteString.copyFromUtf8(
+                (java.lang.String) ref);
+        uuid_ = b;
+        return b;
+      } else {
+        return (com.google.protobuf.ByteString) ref;
+      }
+    }
+
+    private void initFields() {
+      uuid_ = "";
+    }
+    private byte memoizedIsInitialized = -1;
+    public final boolean isInitialized() {
+      byte isInitialized = memoizedIsInitialized;
+      if (isInitialized != -1) return isInitialized == 1;
+
+      memoizedIsInitialized = 1;
+      return true;
+    }
+
+    public void writeTo(com.google.protobuf.CodedOutputStream output)
+                        throws java.io.IOException {
+      getSerializedSize();
+      if (((bitField0_ & 0x00000001) == 0x00000001)) {
+        output.writeBytes(1, getUuidBytes());
+      }
+      getUnknownFields().writeTo(output);
+    }
+
+    private int memoizedSerializedSize = -1;
+    public int getSerializedSize() {
+      int size = memoizedSerializedSize;
+      if (size != -1) return size;
+
+      size = 0;
+      if (((bitField0_ & 0x00000001) == 0x00000001)) {
+        size += com.google.protobuf.CodedOutputStream
+          .computeBytesSize(1, getUuidBytes());
+      }
+      size += getUnknownFields().getSerializedSize();
+      memoizedSerializedSize = size;
+      return size;
+    }
+
+    private static final long serialVersionUID = 0L;
+    @java.lang.Override
+    protected java.lang.Object writeReplace()
+        throws java.io.ObjectStreamException {
+      return super.writeReplace();
+    }
+
+    public static org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid parseFrom(
+        com.google.protobuf.ByteString data)
+        throws com.google.protobuf.InvalidProtocolBufferException {
+      return PARSER.parseFrom(data);
+    }
+    public static org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid parseFrom(
+        com.google.protobuf.ByteString data,
+        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
+        throws com.google.protobuf.InvalidProtocolBufferException {
+      return PARSER.parseFrom(data, extensionRegistry);
+    }
+    public static org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid parseFrom(byte[] data)
+        throws com.google.protobuf.InvalidProtocolBufferException {
+      return PARSER.parseFrom(data);
+    }
+    public static org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid parseFrom(
+        byte[] data,
+        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
+        throws com.google.protobuf.InvalidProtocolBufferException {
+      return PARSER.parseFrom(data, extensionRegistry);
+    }
+    public static org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid parseFrom(java.io.InputStream input)
+        throws java.io.IOException {
+      return PARSER.parseFrom(input);
+    }
+    public static org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid parseFrom(
+        java.io.InputStream input,
+        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
+        throws java.io.IOException {
+      return PARSER.parseFrom(input, extensionRegistry);
+    }
+    public static org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid parseDelimitedFrom(java.io.InputStream input)
+        throws java.io.IOException {
+      return PARSER.parseDelimitedFrom(input);
+    }
+    public static org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid parseDelimitedFrom(
+        java.io.InputStream input,
+        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
+        throws java.io.IOException {
+      return PARSER.parseDelimitedFrom(input, extensionRegistry);
+    }
+    public static org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid parseFrom(
+        com.google.protobuf.CodedInputStream input)
+        throws java.io.IOException {
+      return PARSER.parseFrom(input);
+    }
+    public static org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid parseFrom(
+        com.google.protobuf.CodedInputStream input,
+        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
+        throws java.io.IOException {
+      return PARSER.parseFrom(input, extensionRegistry);
+    }
+
+    public static Builder newBuilder() { return Builder.create(); }
+    public Builder newBuilderForType() { return newBuilder(); }
+    public static Builder newBuilder(org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid prototype) {
+      return newBuilder().mergeFrom(prototype);
+    }
+    public Builder toBuilder() { return newBuilder(this); }
+
+    @java.lang.Override
+    protected Builder newBuilderForType(
+        com.google.protobuf.GeneratedMessage.BuilderParent parent) {
+      Builder builder = new Builder(parent);
+      return builder;
+    }
+    /**
+     * Protobuf type {@code textsecure.ProvisioningUuid}
+     */
+    public static final class Builder extends
+        com.google.protobuf.GeneratedMessage.Builder<Builder>
+       implements org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuidOrBuilder {
+      public static final com.google.protobuf.Descriptors.Descriptor
+          getDescriptor() {
+        return org.whispersystems.textsecuregcm.entities.MessageProtos.internal_static_textsecure_ProvisioningUuid_descriptor;
+      }
+
+      protected com.google.protobuf.GeneratedMessage.FieldAccessorTable
+          internalGetFieldAccessorTable() {
+        return org.whispersystems.textsecuregcm.entities.MessageProtos.internal_static_textsecure_ProvisioningUuid_fieldAccessorTable
+            .ensureFieldAccessorsInitialized(
+                org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid.class, org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid.Builder.class);
+      }
+
+      // Construct using org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid.newBuilder()
+      private Builder() {
+        maybeForceBuilderInitialization();
+      }
+
+      private Builder(
+          com.google.protobuf.GeneratedMessage.BuilderParent parent) {
+        super(parent);
+        maybeForceBuilderInitialization();
+      }
+      private void maybeForceBuilderInitialization() {
+        if (com.google.protobuf.GeneratedMessage.alwaysUseFieldBuilders) {
+        }
+      }
+      private static Builder create() {
+        return new Builder();
+      }
+
+      public Builder clear() {
+        super.clear();
+        uuid_ = "";
+        bitField0_ = (bitField0_ & ~0x00000001);
+        return this;
+      }
+
+      public Builder clone() {
+        return create().mergeFrom(buildPartial());
+      }
+
+      public com.google.protobuf.Descriptors.Descriptor
+          getDescriptorForType() {
+        return org.whispersystems.textsecuregcm.entities.MessageProtos.internal_static_textsecure_ProvisioningUuid_descriptor;
+      }
+
+      public org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid getDefaultInstanceForType() {
+        return org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid.getDefaultInstance();
+      }
+
+      public org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid build() {
+        org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid result = buildPartial();
+        if (!result.isInitialized()) {
+          throw newUninitializedMessageException(result);
+        }
+        return result;
+      }
+
+      public org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid buildPartial() {
+        org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid result = new org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid(this);
+        int from_bitField0_ = bitField0_;
+        int to_bitField0_ = 0;
+        if (((from_bitField0_ & 0x00000001) == 0x00000001)) {
+          to_bitField0_ |= 0x00000001;
+        }
+        result.uuid_ = uuid_;
+        result.bitField0_ = to_bitField0_;
+        onBuilt();
+        return result;
+      }
+
+      public Builder mergeFrom(com.google.protobuf.Message other) {
+        if (other instanceof org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid) {
+          return mergeFrom((org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid)other);
+        } else {
+          super.mergeFrom(other);
+          return this;
+        }
+      }
+
+      public Builder mergeFrom(org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid other) {
+        if (other == org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid.getDefaultInstance()) return this;
+        if (other.hasUuid()) {
+          bitField0_ |= 0x00000001;
+          uuid_ = other.uuid_;
+          onChanged();
+        }
+        this.mergeUnknownFields(other.getUnknownFields());
+        return this;
+      }
+
+      public final boolean isInitialized() {
+        return true;
+      }
+
+      public Builder mergeFrom(
+          com.google.protobuf.CodedInputStream input,
+          com.google.protobuf.ExtensionRegistryLite extensionRegistry)
+          throws java.io.IOException {
+        org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid parsedMessage = null;
+        try {
+          parsedMessage = PARSER.parsePartialFrom(input, extensionRegistry);
+        } catch (com.google.protobuf.InvalidProtocolBufferException e) {
+          parsedMessage = (org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid) e.getUnfinishedMessage();
+          throw e;
+        } finally {
+          if (parsedMessage != null) {
+            mergeFrom(parsedMessage);
+          }
+        }
+        return this;
+      }
+      private int bitField0_;
+
+      // optional string uuid = 1;
+      private java.lang.Object uuid_ = "";
+      /**
+       * <code>optional string uuid = 1;</code>
+       */
+      public boolean hasUuid() {
+        return ((bitField0_ & 0x00000001) == 0x00000001);
+      }
+      /**
+       * <code>optional string uuid = 1;</code>
+       */
+      public java.lang.String getUuid() {
+        java.lang.Object ref = uuid_;
+        if (!(ref instanceof java.lang.String)) {
+          java.lang.String s = ((com.google.protobuf.ByteString) ref)
+              .toStringUtf8();
+          uuid_ = s;
+          return s;
+        } else {
+          return (java.lang.String) ref;
+        }
+      }
+      /**
+       * <code>optional string uuid = 1;</code>
+       */
+      public com.google.protobuf.ByteString
+          getUuidBytes() {
+        java.lang.Object ref = uuid_;
+        if (ref instanceof String) {
+          com.google.protobuf.ByteString b = 
+              com.google.protobuf.ByteString.copyFromUtf8(
+                  (java.lang.String) ref);
+          uuid_ = b;
+          return b;
+        } else {
+          return (com.google.protobuf.ByteString) ref;
+        }
+      }
+      /**
+       * <code>optional string uuid = 1;</code>
+       */
+      public Builder setUuid(
+          java.lang.String value) {
+        if (value == null) {
+    throw new NullPointerException();
+  }
+  bitField0_ |= 0x00000001;
+        uuid_ = value;
+        onChanged();
+        return this;
+      }
+      /**
+       * <code>optional string uuid = 1;</code>
+       */
+      public Builder clearUuid() {
+        bitField0_ = (bitField0_ & ~0x00000001);
+        uuid_ = getDefaultInstance().getUuid();
+        onChanged();
+        return this;
+      }
+      /**
+       * <code>optional string uuid = 1;</code>
+       */
+      public Builder setUuidBytes(
+          com.google.protobuf.ByteString value) {
+        if (value == null) {
+    throw new NullPointerException();
+  }
+  bitField0_ |= 0x00000001;
+        uuid_ = value;
+        onChanged();
+        return this;
+      }
+
+      // @@protoc_insertion_point(builder_scope:textsecure.ProvisioningUuid)
+    }
+
+    static {
+      defaultInstance = new ProvisioningUuid(true);
+      defaultInstance.initFields();
+    }
+
+    // @@protoc_insertion_point(class_scope:textsecure.ProvisioningUuid)
+  }
+
   private static com.google.protobuf.Descriptors.Descriptor
     internal_static_textsecure_OutgoingMessageSignal_descriptor;
   private static
     com.google.protobuf.GeneratedMessage.FieldAccessorTable
       internal_static_textsecure_OutgoingMessageSignal_fieldAccessorTable;
+  private static com.google.protobuf.Descriptors.Descriptor
+    internal_static_textsecure_ProvisioningUuid_descriptor;
+  private static
+    com.google.protobuf.GeneratedMessage.FieldAccessorTable
+      internal_static_textsecure_ProvisioningUuid_fieldAccessorTable;
 
   public static com.google.protobuf.Descriptors.FileDescriptor
       getDescriptor() {
@@ -1132,9 +1608,10 @@ public final class MessageProtos {
       "\r\n\005relay\030\003 \001(\t\022\021\n\ttimestamp\030\005 \001(\004\022\017\n\007mes" +
       "sage\030\006 \001(\014\"d\n\004Type\022\013\n\007UNKNOWN\020\000\022\016\n\nCIPHE" +
       "RTEXT\020\001\022\020\n\014KEY_EXCHANGE\020\002\022\021\n\rPREKEY_BUND" +
-      "LE\020\003\022\r\n\tPLAINTEXT\020\004\022\013\n\007RECEIPT\020\005B:\n)org." +
+      "LE\020\003\022\r\n\tPLAINTEXT\020\004\022\013\n\007RECEIPT\020\005\" \n\020Prov" +
-      "whispersystems.textsecuregcm.entitiesB\rM" +
+      "isioningUuid\022\014\n\004uuid\030\001 \001(\tB:\n)org.whispe" +
-      "essageProtos"
+      "rsystems.textsecuregcm.entitiesB\rMessage" +
+      "Protos"
     };
     com.google.protobuf.Descriptors.FileDescriptor.InternalDescriptorAssigner assigner =
       new com.google.protobuf.Descriptors.FileDescriptor.InternalDescriptorAssigner() {
@@ -1147,6 +1624,12 @@ public final class MessageProtos {
             com.google.protobuf.GeneratedMessage.FieldAccessorTable(
               internal_static_textsecure_OutgoingMessageSignal_descriptor,
               new java.lang.String[] { "Type", "Source", "SourceDevice", "Relay", "Timestamp", "Message", });
+          internal_static_textsecure_ProvisioningUuid_descriptor =
+            getDescriptor().getMessageTypes().get(1);
+          internal_static_textsecure_ProvisioningUuid_fieldAccessorTable = new
+            com.google.protobuf.GeneratedMessage.FieldAccessorTable(
+              internal_static_textsecure_ProvisioningUuid_descriptor,
+              new java.lang.String[] { "Uuid", });
           return null;
         }
       };

src/main/java/org/whispersystems/textsecuregcm/entities/ProvisioningMessage.java

@@ -0,0 +1,19 @@
+package org.whispersystems.textsecuregcm.entities;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+public class ProvisioningMessage {
+
+  @JsonProperty
+  private String body;
+
+  public ProvisioningMessage() {}
+
+  public ProvisioningMessage(String body) {
+    this.body = body;
+  }
+
+  public String getBody() {
+    return body;
+  }
+}

src/main/java/org/whispersystems/textsecuregcm/mappers/InvalidWebsocketAddressExceptionMapper.java

@@ -0,0 +1,15 @@
+package org.whispersystems.textsecuregcm.mappers;
+
+import org.whispersystems.textsecuregcm.websocket.InvalidWebsocketAddressException;
+
+import javax.ws.rs.core.Response;
+import javax.ws.rs.ext.ExceptionMapper;
+import javax.ws.rs.ext.Provider;
+
+@Provider
+public class InvalidWebsocketAddressExceptionMapper implements ExceptionMapper<InvalidWebsocketAddressException> {
+  @Override
+  public Response toResponse(InvalidWebsocketAddressException exception) {
+    return Response.status(Response.Status.BAD_REQUEST).build();
+  }
+}

src/main/java/org/whispersystems/textsecuregcm/push/PushSender.java

@@ -50,6 +50,10 @@ public class PushSender {
     else                                  throw new NotPushRegisteredException("No delivery possible!");
   }
 
+  public WebsocketSender getWebSocketSender() {
+    return webSocketSender;
+  }
+
   private void sendGcmMessage(Account account, Device device, OutgoingMessageSignal message)
       throws TransientPushFailureException, NotPushRegisteredException
   {

src/main/java/org/whispersystems/textsecuregcm/push/WebsocketSender.java

@@ -19,6 +19,7 @@ package org.whispersystems.textsecuregcm.push;
 import com.codahale.metrics.Meter;
 import com.codahale.metrics.MetricRegistry;
 import com.codahale.metrics.SharedMetricRegistries;
+import com.google.protobuf.ByteString;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.whispersystems.textsecuregcm.storage.Account;
@@ -26,8 +27,11 @@ import org.whispersystems.textsecuregcm.storage.Device;
 import org.whispersystems.textsecuregcm.storage.PubSubManager;
 import org.whispersystems.textsecuregcm.storage.StoredMessages;
 import org.whispersystems.textsecuregcm.util.Constants;
+import org.whispersystems.textsecuregcm.websocket.ProvisioningAddress;
 import org.whispersystems.textsecuregcm.websocket.WebsocketAddress;
 
+import java.io.UnsupportedEncodingException;
+
 import static com.codahale.metrics.MetricRegistry.name;
 import static org.whispersystems.textsecuregcm.entities.MessageProtos.OutgoingMessageSignal;
 import static org.whispersystems.textsecuregcm.storage.PubSubProtos.PubSubMessage;
@@ -44,6 +48,9 @@ public class WebsocketSender {
   private final Meter apnOnlineMeter        = metricRegistry.meter(name(getClass(), "apn_online" ));
   private final Meter apnOfflineMeter       = metricRegistry.meter(name(getClass(), "apn_offline"));
 
+  private final Meter provisioningOnlineMeter  = metricRegistry.meter(name(getClass(), "provisioning_online" ));
+  private final Meter provisioningOfflineMeter = metricRegistry.meter(name(getClass(), "provisioning_offline"));
+
   private final StoredMessages storedMessages;
   private final PubSubManager  pubSubManager;
 
@@ -76,4 +83,23 @@ public class WebsocketSender {
       return false;
     }
   }
+
+  public boolean sendProvisioningMessage(ProvisioningAddress address, String body) {
+    try {
+      PubSubMessage    pubSubMessage = PubSubMessage.newBuilder()
+                                                    .setType(PubSubMessage.Type.DELIVER)
+                                                    .setContent(ByteString.copyFrom(body, "UTF-8"))
+                                                    .build();
+
+      if (pubSubManager.publish(address, pubSubMessage)) {
+        provisioningOnlineMeter.mark();
+        return true;
+      } else {
+        provisioningOfflineMeter.mark();
+        return false;
+      }
+    } catch (UnsupportedEncodingException e) {
+      throw new AssertionError(e);
+    }
+  }
 }

src/main/java/org/whispersystems/textsecuregcm/websocket/AuthenticatedConnectListener.java

@@ -12,7 +12,7 @@ import org.whispersystems.textsecuregcm.storage.StoredMessages;
 import org.whispersystems.websocket.session.WebSocketSessionContext;
 import org.whispersystems.websocket.setup.WebSocketConnectListener;
 
-public class ConnectListener implements WebSocketConnectListener {
+public class AuthenticatedConnectListener implements WebSocketConnectListener {
 
   private static final Logger logger = LoggerFactory.getLogger(WebSocketConnection.class);
 
@@ -21,7 +21,7 @@ public class ConnectListener implements WebSocketConnectListener {
   private final StoredMessages  storedMessages;
   private final PubSubManager   pubSubManager;
 
-  public ConnectListener(AccountsManager accountsManager, PushSender pushSender,
+  public AuthenticatedConnectListener(AccountsManager accountsManager, PushSender pushSender,
                                       StoredMessages storedMessages, PubSubManager pubSubManager)
   {
     this.accountsManager = accountsManager;

src/main/java/org/whispersystems/textsecuregcm/websocket/ProvisioningAddress.java

@@ -0,0 +1,38 @@
+package org.whispersystems.textsecuregcm.websocket;
+
+import org.whispersystems.textsecuregcm.util.Base64;
+
+import java.security.NoSuchAlgorithmException;
+import java.security.SecureRandom;
+
+public class ProvisioningAddress extends WebsocketAddress {
+
+  private static final String PREFIX = ">>ephemeral-";
+
+  private final String address;
+
+  public ProvisioningAddress(String address) throws InvalidWebsocketAddressException {
+    super(address, 0);
+    this.address = address;
+
+    if (address == null || !address.startsWith(PREFIX)) {
+      throw new InvalidWebsocketAddressException(address);
+    }
+  }
+
+  public String getAddress() {
+    return address;
+  }
+
+  public static ProvisioningAddress generate() {
+    try {
+      byte[] random = new byte[16];
+      SecureRandom.getInstance("SHA1PRNG").nextBytes(random);
+
+      return new ProvisioningAddress(PREFIX + Base64.encodeBytesWithoutPadding(random)
+                                                    .replace('+', '-').replace('/', '_'));
+    } catch (NoSuchAlgorithmException | InvalidWebsocketAddressException e) {
+      throw new AssertionError(e);
+    }
+  }
+}

src/main/java/org/whispersystems/textsecuregcm/websocket/ProvisioningConnectListener.java

@@ -0,0 +1,27 @@
+package org.whispersystems.textsecuregcm.websocket;
+
+import org.whispersystems.textsecuregcm.storage.PubSubManager;
+import org.whispersystems.websocket.session.WebSocketSessionContext;
+import org.whispersystems.websocket.setup.WebSocketConnectListener;
+
+public class ProvisioningConnectListener implements WebSocketConnectListener {
+
+  private final PubSubManager pubSubManager;
+
+  public ProvisioningConnectListener(PubSubManager pubSubManager) {
+    this.pubSubManager = pubSubManager;
+  }
+
+  @Override
+  public void onWebSocketConnect(WebSocketSessionContext context) {
+    final ProvisioningConnection connection = new ProvisioningConnection(pubSubManager, context.getClient());
+    connection.onConnected();
+
+    context.addListener(new WebSocketSessionContext.WebSocketEventListener() {
+      @Override
+      public void onWebSocketClose(WebSocketSessionContext context, int statusCode, String reason) {
+        connection.onConnectionLost();
+      }
+    });
+  }
+}

src/main/java/org/whispersystems/textsecuregcm/websocket/ProvisioningConnection.java

@@ -0,0 +1,61 @@
+package org.whispersystems.textsecuregcm.websocket;
+
+import com.google.common.base.Optional;
+import com.google.common.util.concurrent.FutureCallback;
+import com.google.common.util.concurrent.Futures;
+import com.google.common.util.concurrent.ListenableFuture;
+import org.whispersystems.textsecuregcm.entities.MessageProtos.ProvisioningUuid;
+import org.whispersystems.textsecuregcm.storage.PubSubListener;
+import org.whispersystems.textsecuregcm.storage.PubSubManager;
+import org.whispersystems.textsecuregcm.storage.PubSubProtos.PubSubMessage;
+import org.whispersystems.websocket.WebSocketClient;
+import org.whispersystems.websocket.messages.WebSocketResponseMessage;
+
+public class ProvisioningConnection implements PubSubListener {
+
+  private final PubSubManager       pubSubManager;
+  private final ProvisioningAddress provisioningAddress;
+  private final WebSocketClient     client;
+
+  public ProvisioningConnection(PubSubManager pubSubManager, WebSocketClient client) {
+    this.pubSubManager       = pubSubManager;
+    this.client              = client;
+    this.provisioningAddress = ProvisioningAddress.generate();
+  }
+
+  @Override
+  public void onPubSubMessage(PubSubMessage outgoingMessage) {
+    if (outgoingMessage.getType() == PubSubMessage.Type.DELIVER) {
+      Optional<byte[]> body = Optional.of(outgoingMessage.getContent().toByteArray());
+
+      ListenableFuture<WebSocketResponseMessage> response = client.sendRequest("PUT", "/v1/message", body);
+
+      Futures.addCallback(response, new FutureCallback<WebSocketResponseMessage>() {
+        @Override
+        public void onSuccess(WebSocketResponseMessage webSocketResponseMessage) {
+          pubSubManager.unsubscribe(provisioningAddress, ProvisioningConnection.this);
+          client.close(1001, "All you get.");
+        }
+
+        @Override
+        public void onFailure(Throwable throwable) {
+          pubSubManager.unsubscribe(provisioningAddress, ProvisioningConnection.this);
+          client.close(1001, "That's all!");
+        }
+      });
+    }
+  }
+
+  public void onConnected() {
+    this.pubSubManager.subscribe(provisioningAddress, this);
+    this.client.sendRequest("PUT", "/v1/address", Optional.of(ProvisioningUuid.newBuilder()
+                                                                              .setUuid(provisioningAddress.getAddress())
+                                                                              .build()
+                                                                              .toByteArray()));
+  }
+
+  public void onConnectionLost() {
+    this.pubSubManager.unsubscribe(provisioningAddress, this);
+    this.client.close(1001, "Done");
+  }
+}

src/test/java/org/whispersystems/textsecuregcm/tests/websocket/WebSocketConnectionTest.java

@@ -15,7 +15,7 @@ import org.whispersystems.textsecuregcm.storage.Device;
 import org.whispersystems.textsecuregcm.storage.PubSubManager;
 import org.whispersystems.textsecuregcm.storage.StoredMessages;
 import org.whispersystems.textsecuregcm.util.Base64;
-import org.whispersystems.textsecuregcm.websocket.ConnectListener;
+import org.whispersystems.textsecuregcm.websocket.AuthenticatedConnectListener;
 import org.whispersystems.textsecuregcm.websocket.WebSocketAccountAuthenticator;
 import org.whispersystems.textsecuregcm.websocket.WebSocketConnection;
 import org.whispersystems.textsecuregcm.websocket.WebsocketAddress;
@@ -58,7 +58,7 @@ public class WebSocketConnectionTest {
   public void testCredentials() throws Exception {
     StoredMessages                storedMessages         = mock(StoredMessages.class);
     WebSocketAccountAuthenticator webSocketAuthenticator = new WebSocketAccountAuthenticator(accountAuthenticator);
-    ConnectListener               connectListener        = new ConnectListener(accountsManager, pushSender, storedMessages, pubSubManager);
+    AuthenticatedConnectListener connectListener        = new AuthenticatedConnectListener(accountsManager, pushSender, storedMessages, pubSubManager);
     WebSocketSessionContext       sessionContext         = mock(WebSocketSessionContext.class);
 
     when(accountAuthenticator.authenticate(eq(new BasicCredentials(VALID_USER, VALID_PASSWORD))))