address: IPv4/IPv6 dual bind.

RAW_RELEASE_NOTES.md

@@ -14,3 +14,4 @@ final version.
 * Added support for dynamic response header values (`%CLIENT_IP%` and `%PROTOCOL%`).
 * Added native DogStatsD support. :ref:`DogStatsdSink <envoy_api_msg_DogStatsdSink>`
 * grpc-json: Added support inline descriptor in config.
+* Added support for listening for both IPv4 and IPv6 when binding to ::.

include/envoy/network/address.h

@@ -85,6 +85,11 @@ class Ip {
    * @return the version of IP address.
    */
   virtual IpVersion version() const PURE;
+
+  /**
+   * @return IPv4-IPv6 mapping disabled for IPv6 addresses?
+   */
+  virtual bool v6only() const PURE;
 };
 
 enum class Type { Ip, Pipe };

source/common/network/address_impl.cc

@@ -20,7 +20,8 @@ namespace Envoy {
 namespace Network {
 namespace Address {
 
-Address::InstanceConstSharedPtr addressFromSockAddr(const sockaddr_storage& ss, socklen_t ss_len) {
+Address::InstanceConstSharedPtr addressFromSockAddr(const sockaddr_storage& ss, socklen_t ss_len,
+                                                    bool v6only) {
   RELEASE_ASSERT(ss_len == 0 || ss_len >= sizeof(sa_family_t));
   switch (ss.ss_family) {
   case AF_INET: {
@@ -33,7 +34,7 @@ Address::InstanceConstSharedPtr addressFromSockAddr(const sockaddr_storage& ss,
     RELEASE_ASSERT(ss_len == 0 || ss_len == sizeof(sockaddr_in6));
     const struct sockaddr_in6* sin6 = reinterpret_cast<const struct sockaddr_in6*>(&ss);
     ASSERT(AF_INET6 == sin6->sin6_family);
-    return std::make_shared<Address::Ipv6Instance>(*sin6);
+    return std::make_shared<Address::Ipv6Instance>(*sin6, v6only);
   }
   case AF_UNIX: {
     const struct sockaddr_un* sun = reinterpret_cast<const struct sockaddr_un*>(&ss);
@@ -47,14 +48,14 @@ Address::InstanceConstSharedPtr addressFromSockAddr(const sockaddr_storage& ss,
   NOT_REACHED;
 }
 
-InstanceConstSharedPtr addressFromFd(int fd) {
+InstanceConstSharedPtr addressFromFd(int fd, bool v6only) {
   sockaddr_storage ss;
   socklen_t ss_len = sizeof ss;
   const int rc = ::getsockname(fd, reinterpret_cast<sockaddr*>(&ss), &ss_len);
   if (rc != 0) {
     throw EnvoyException(fmt::format("getsockname failed for '{}': {}", fd, strerror(errno)));
   }
-  return addressFromSockAddr(ss, ss_len);
+  return addressFromSockAddr(ss, ss_len, v6only);
 }
 
 InstanceConstSharedPtr peerAddressFromFd(int fd) {
@@ -179,9 +180,10 @@ std::string Ipv6Instance::Ipv6Helper::makeFriendlyAddress() const {
   return ptr;
 }
 
-Ipv6Instance::Ipv6Instance(const sockaddr_in6& address) : InstanceBase(Type::Ip) {
+Ipv6Instance::Ipv6Instance(const sockaddr_in6& address, bool v6only) : InstanceBase(Type::Ip) {
   ip_.ipv6_.address_ = address;
   ip_.friendly_address_ = ip_.ipv6_.makeFriendlyAddress();
+  ip_.v6only_ = v6only;
   friendly_name_ = fmt::format("[{}]:{}", ip_.friendly_address_, ip_.port());
 }
 
@@ -219,7 +221,7 @@ int Ipv6Instance::socket(SocketType type) const {
   const int fd = socketFromSocketType(type);
 
   // Setting IPV6_V6ONLY resticts the IPv6 socket to IPv6 connections only.
-  const int v6only = 1;
+  const int v6only = ip_.v6only_;
   RELEASE_ASSERT(::setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &v6only, sizeof(v6only)) != -1);
   return fd;
 }

source/common/network/address_impl.h

@@ -21,16 +21,19 @@ namespace Address {
  * @param ss a valid address with family AF_INET, AF_INET6 or AF_UNIX.
  * @param len length of the address (e.g. from accept, getsockname or getpeername). If len > 0,
  *        it is used to validate the structure contents; else if len == 0, it is ignored.
+ * @param v6only disable IPv4-IPv6 mapping for IPv6 addresses?
  * @return InstanceConstSharedPtr the address.
  */
-Address::InstanceConstSharedPtr addressFromSockAddr(const sockaddr_storage& ss, socklen_t len);
+Address::InstanceConstSharedPtr addressFromSockAddr(const sockaddr_storage& ss, socklen_t len,
+                                                    bool v6only = true);
 
 /**
  * Obtain an address from a bound file descriptor. Raises an EnvoyException on failure.
  * @param fd file descriptor.
+ * @param v6only disable IPv4-IPv6 mapping for IPv6 addresses?
  * @return InstanceConstSharedPtr for bound address.
  */
-InstanceConstSharedPtr addressFromFd(int fd);
+InstanceConstSharedPtr addressFromFd(int fd, bool v6only = true);
 
 /**
  * Obtain the address of the peer of the socket with the specified file descriptor.
@@ -113,6 +116,7 @@ class Ipv4Instance : public InstanceBase {
     const Ipv6* ipv6() const override { return nullptr; }
     uint32_t port() const override { return ntohs(ipv4_.address_.sin_port); }
     IpVersion version() const override { return IpVersion::v4; }
+    bool v6only() const override { return false; }
 
     Ipv4Helper ipv4_;
     std::string friendly_address_;
@@ -129,7 +133,7 @@ class Ipv6Instance : public InstanceBase {
   /**
    * Construct from an existing unix IPv6 socket address (IP v6 address and port).
    */
-  explicit Ipv6Instance(const sockaddr_in6& address);
+  Ipv6Instance(const sockaddr_in6& address, bool v6only = true);
 
   /**
    * Construct from a string IPv6 address such as "12:34::5". Port will be unset/0.
@@ -175,9 +179,14 @@ class Ipv6Instance : public InstanceBase {
     const Ipv6* ipv6() const override { return &ipv6_; }
     uint32_t port() const override { return ipv6_.port(); }
     IpVersion version() const override { return IpVersion::v6; }
+    bool v6only() const override { return v6only_; }
 
     Ipv6Helper ipv6_;
     std::string friendly_address_;
+    // Is IPv4 compatibility (https://tools.ietf.org/html/rfc3493#page-11) disabled?
+    // Default initialized to true to preserve extant Envoy behavior where we don't explicitly set
+    // this in the constructor.
+    bool v6only_{true};
   };
 
   IpHelper ip_;

source/common/network/resolver_impl.cc

@@ -26,8 +26,8 @@ class IpResolver : public Resolver {
     case envoy::api::v2::SocketAddress::kPortValue:
     // Default to port 0 if no port value is specified.
     case envoy::api::v2::SocketAddress::PORT_SPECIFIER_NOT_SET:
-      return Network::Utility::parseInternetAddress(socket_address.address(),
-                                                    socket_address.port_value());
+      return Network::Utility::parseInternetAddress(
+          socket_address.address(), socket_address.port_value(), !socket_address.ipv4_compat());
 
     default:
       throw EnvoyException(fmt::format("IP resolver can't handle port specifier type {}",

source/common/network/utility.cc

@@ -81,7 +81,7 @@ uint32_t Utility::portFromTcpUrl(const std::string& url) {
 }
 
 Address::InstanceConstSharedPtr Utility::parseInternetAddress(const std::string& ip_address,
-                                                              uint16_t port) {
+                                                              uint16_t port, bool v6only) {
   sockaddr_in sa4;
   if (inet_pton(AF_INET, ip_address.c_str(), &sa4.sin_addr) == 1) {
     sa4.sin_family = AF_INET;
@@ -92,14 +92,14 @@ Address::InstanceConstSharedPtr Utility::parseInternetAddress(const std::string&
   if (inet_pton(AF_INET6, ip_address.c_str(), &sa6.sin6_addr) == 1) {
     sa6.sin6_family = AF_INET6;
     sa6.sin6_port = htons(port);
-    return std::make_shared<Address::Ipv6Instance>(sa6);
+    return std::make_shared<Address::Ipv6Instance>(sa6, v6only);
   }
   throwWithMalformedIp(ip_address);
   NOT_REACHED;
 }
 
-Address::InstanceConstSharedPtr
-Utility::parseInternetAddressAndPort(const std::string& ip_address) {
+Address::InstanceConstSharedPtr Utility::parseInternetAddressAndPort(const std::string& ip_address,
+                                                                     bool v6only) {
   if (ip_address.empty()) {
     throwWithMalformedIp(ip_address);
   }
@@ -121,7 +121,7 @@ Utility::parseInternetAddressAndPort(const std::string& ip_address) {
     }
     sa6.sin6_family = AF_INET6;
     sa6.sin6_port = htons(port64);
-    return std::make_shared<Address::Ipv6Instance>(sa6);
+    return std::make_shared<Address::Ipv6Instance>(sa6, v6only);
   }
   // Treat it as an IPv4 address followed by a port.
   auto pos = ip_address.rfind(":");

source/common/network/utility.h

@@ -76,10 +76,11 @@ class Utility {
    * not include a port number. Throws EnvoyException if unable to parse the address.
    * @param ip_address string to be parsed as an internet address.
    * @param port optional port to include in Instance created from ip_address, 0 by default.
+   * @param v6only disable IPv4-IPv6 mapping for IPv6 addresses?
    * @return pointer to the Instance, or nullptr if unable to parse the address.
    */
-  static Address::InstanceConstSharedPtr parseInternetAddress(const std::string& ip_address,
-                                                              uint16_t port = 0);
+  static Address::InstanceConstSharedPtr
+  parseInternetAddress(const std::string& ip_address, uint16_t port = 0, bool v6only = true);
 
   /**
    * Parse an internet host address (IPv4 or IPv6) AND port, and create an Instance from it. Throws
@@ -95,9 +96,11 @@ class Utility {
    * @param ip_addr string to be parsed as an internet address and port. Examples:
    *        - "1.2.3.4:80"
    *        - "[1234:5678::9]:443"
+   * @param v6only disable IPv4-IPv6 mapping for IPv6 addresses?
    * @return pointer to the Instance.
    */
-  static Address::InstanceConstSharedPtr parseInternetAddressAndPort(const std::string& ip_address);
+  static Address::InstanceConstSharedPtr parseInternetAddressAndPort(const std::string& ip_address,
+                                                                     bool v6only = true);
 
   /**
    * Get the local address of the first interface address that is of type

source/server/listener_manager_impl.cc

@@ -76,7 +76,8 @@ ListenerImpl::ListenerImpl(const envoy::api::v2::Listener& config, ListenerManag
       // TODO(htuch): Validate not pipe when doing v2.
       address_(
           Network::Utility::parseInternetAddress(config.address().socket_address().address(),
-                                                 config.address().socket_address().port_value())),
+                                                 config.address().socket_address().port_value(),
+                                                 !config.address().socket_address().ipv4_compat())),
       global_scope_(parent_.server_.stats().createScope("")),
       listener_scope_(
           parent_.server_.stats().createScope(fmt::format("listener.{}.", address_->asString()))),

test/common/network/address_impl_test.cc

@@ -38,9 +38,11 @@ void makeFdBlocking(int fd) {
   ASSERT_EQ(::fcntl(fd, F_SETFL, flags & (~O_NONBLOCK)), 0);
 }
 
-void testSocketBindAndConnect(const std::string& addr_port_str) {
-  auto addr_port = Network::Utility::parseInternetAddressAndPort(addr_port_str);
+void testSocketBindAndConnect(Network::Address::IpVersion ip_version, bool v6only) {
+  auto addr_port = Network::Utility::parseInternetAddressAndPort(
+      fmt::format("{}:0", Network::Test::getAnyAddressUrlString(ip_version)), v6only);
   ASSERT_NE(addr_port, nullptr);
+
   if (addr_port->ip()->port() == 0) {
     addr_port = Network::Test::findOrCheckFreePort(addr_port, SocketType::Stream);
   }
@@ -54,36 +56,50 @@ void testSocketBindAndConnect(const std::string& addr_port_str) {
 
   // Check that IPv6 sockets accept IPv6 connections only.
   if (addr_port->ip()->version() == IpVersion::v6) {
-    int v6only = 0;
-    socklen_t size_int = sizeof(v6only);
-    ASSERT_GE(::getsockopt(listen_fd, IPPROTO_IPV6, IPV6_V6ONLY, &v6only, &size_int), 0);
-    EXPECT_EQ(v6only, 1);
+    int socket_v6only = 0;
+    socklen_t size_int = sizeof(socket_v6only);
+    ASSERT_GE(::getsockopt(listen_fd, IPPROTO_IPV6, IPV6_V6ONLY, &socket_v6only, &size_int), 0);
+    EXPECT_EQ(v6only, socket_v6only);
+    EXPECT_EQ(v6only, addr_port->ip()->v6only());
   }
 
   // Bind the socket to the desired address and port.
-  int rc = addr_port->bind(listen_fd);
-  int err = errno;
+  const int rc = addr_port->bind(listen_fd);
+  const int err = errno;
   ASSERT_EQ(rc, 0) << addr_port->asString() << "\nerror: " << strerror(err) << "\nerrno: " << err;
 
   // Do a bare listen syscall. Not bothering to accept connections as that would
   // require another thread.
-  ASSERT_EQ(::listen(listen_fd, 1), 0);
-
-  // Create a client socket and connect to the server.
-  const int client_fd = addr_port->socket(SocketType::Stream);
-  ASSERT_GE(client_fd, 0) << addr_port->asString();
-  ScopedFdCloser closer2(client_fd);
-
-  // Instance::socket creates a non-blocking socket, which that extends all the way to the
-  // operation of ::connect(), so connect returns with errno==EWOULDBLOCK before the tcp
-  // handshake can complete. For testing convenience, re-enable blocking on the socket
-  // so that connect will wait for the handshake to complete.
-  makeFdBlocking(client_fd);
-
-  // Connect to the server.
-  rc = addr_port->connect(client_fd);
-  err = errno;
-  ASSERT_EQ(rc, 0) << addr_port->asString() << "\nerror: " << strerror(err) << "\nerrno: " << err;
+  ASSERT_EQ(::listen(listen_fd, 128), 0);
+
+  auto client_connect = [](Address::InstanceConstSharedPtr addr_port) {
+    // Create a client socket and connect to the server.
+    const int client_fd = addr_port->socket(SocketType::Stream);
+    ASSERT_GE(client_fd, 0) << addr_port->asString();
+    ScopedFdCloser closer2(client_fd);
+
+    // Instance::socket creates a non-blocking socket, which that extends all the way to the
+    // operation of ::connect(), so connect returns with errno==EWOULDBLOCK before the tcp
+    // handshake can complete. For testing convenience, re-enable blocking on the socket
+    // so that connect will wait for the handshake to complete.
+    makeFdBlocking(client_fd);
+
+    // Connect to the server.
+    const int rc = addr_port->connect(client_fd);
+    const int err = errno;
+    ASSERT_EQ(rc, 0) << addr_port->asString() << "\nerror: " << strerror(err) << "\nerrno: " << err;
+  };
+
+  client_connect(addr_port);
+
+  if (!v6only) {
+    ASSERT_EQ(IpVersion::v6, addr_port->ip()->version());
+    auto v4_addr_port = Network::Utility::parseInternetAddress(
+        Network::Test::getLoopbackAddressUrlString(Network::Address::IpVersion::v4),
+        addr_port->ip()->port(), true);
+    ASSERT_NE(v4_addr_port, nullptr);
+    client_connect(v4_addr_port);
+  }
 }
 } // namespace
 
@@ -93,8 +109,13 @@ INSTANTIATE_TEST_CASE_P(IpVersions, AddressImplSocketTest,
 
 TEST_P(AddressImplSocketTest, SocketBindAndConnect) {
   // Test listening on and connecting to an unused port with an IP loopback address.
-  testSocketBindAndConnect(
-      fmt::format("{}:0", Network::Test::getLoopbackAddressUrlString(GetParam())));
+  testSocketBindAndConnect(GetParam(), true);
+}
+
+TEST(Ipv4CompatAddressImplSocktTest, SocketBindAndConnect) {
+  if (TestEnvironment::shouldRunTestForIpVersion(Network::Address::IpVersion::v6)) {
+    testSocketBindAndConnect(Network::Address::IpVersion::v6, false);
+  }
 }
 
 TEST(Ipv4InstanceTest, SocketAddress) {

test/common/network/resolver_impl_test.cc

@@ -51,15 +51,36 @@ TEST(ResolverTest, FromProtoAddress) {
   EXPECT_EQ("1.2.3.4:5", resolveProtoAddress(ipv4_address)->asString());
 
   envoy::api::v2::Address ipv6_address;
-  ipv4_address.mutable_socket_address()->set_address("1::1");
-  ipv4_address.mutable_socket_address()->set_port_value(2);
-  EXPECT_EQ("[1::1]:2", resolveProtoAddress(ipv4_address)->asString());
+  ipv6_address.mutable_socket_address()->set_address("1::1");
+  ipv6_address.mutable_socket_address()->set_port_value(2);
+  EXPECT_EQ("[1::1]:2", resolveProtoAddress(ipv6_address)->asString());
 
   envoy::api::v2::Address pipe_address;
   pipe_address.mutable_pipe()->set_path("/foo/bar");
   EXPECT_EQ("/foo/bar", resolveProtoAddress(pipe_address)->asString());
 }
 
+// Validate correct handling of ipv4_compat field.
+TEST(ResolverTest, FromProtoAddressV4Compat) {
+  {
+    envoy::api::v2::Address ipv6_address;
+    ipv6_address.mutable_socket_address()->set_address("1::1");
+    ipv6_address.mutable_socket_address()->set_port_value(2);
+    auto resolved_addr = resolveProtoAddress(ipv6_address);
+    EXPECT_EQ("[1::1]:2", resolved_addr->asString());
+    EXPECT_TRUE(resolved_addr->ip()->v6only());
+  }
+  {
+    envoy::api::v2::Address ipv6_address;
+    ipv6_address.mutable_socket_address()->set_address("1::1");
+    ipv6_address.mutable_socket_address()->set_port_value(2);
+    ipv6_address.mutable_socket_address()->set_ipv4_compat(true);
+    auto resolved_addr = resolveProtoAddress(ipv6_address);
+    EXPECT_EQ("[1::1]:2", resolved_addr->asString());
+    EXPECT_FALSE(resolved_addr->ip()->v6only());
+  }
+}
+
 class TestResolver : public Resolver {
 public:
   InstanceConstSharedPtr resolve(const envoy::api::v2::SocketAddress& socket_address) override {

test/test_common/network_utility.cc

@@ -65,7 +65,7 @@ Address::InstanceConstSharedPtr findOrCheckFreePort(Address::InstanceConstShared
   // If the port we bind is zero, then the OS will pick a free port for us (assuming there are
   // any), and we need to find out the port number that the OS picked so we can return it.
   if (addr_port->ip()->port() == 0) {
-    return Address::addressFromFd(fd);
+    return Address::addressFromFd(fd, addr_port->ip()->v6only());
   }
   return addr_port;
 }