arc: Move platform2/arc/network/ to platform2/patchpanel
Next step in the arc-networkd -> patchpanel rename, this patch moves the
location of the code.
BUG=b:151879931
TEST=units,flashed image to atlas
TEST=tasts arc.PlayStore, crostini.LaunchTerminal.download
Change-Id: I1b5cf8d670e1631d46f6449b725395157bf88dde
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform2/+/2115863
Tested-by: Garrick Evans <garrick@chromium.org>
Commit-Queue: Garrick Evans <garrick@chromium.org>
Reviewed-by: Hidehiko Abe <hidehiko@chromium.org>
Reviewed-by: Eric Caruso <ejcaruso@chromium.org>
Reviewed-by: Chirantan Ekbote <chirantan@chromium.org>
Reviewed-by: Hugo Benichi <hugobenichi@google.com>
diff --git a/patchpanel/multicast_forwarder.h b/patchpanel/multicast_forwarder.h
new file mode 100644
index 0000000..961cfbf
--- /dev/null
+++ b/patchpanel/multicast_forwarder.h
@@ -0,0 +1,118 @@
+// Copyright 2016 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef PATCHPANEL_MULTICAST_FORWARDER_H_
+#define PATCHPANEL_MULTICAST_FORWARDER_H_
+
+#include <netinet/ip.h>
+#include <sys/socket.h>
+
+#include <map>
+#include <memory>
+#include <set>
+#include <string>
+#include <utility>
+
+#include <base/files/file_descriptor_watcher_posix.h>
+#include <base/files/scoped_file.h>
+#include <base/macros.h>
+
+#include "patchpanel/net_util.h"
+
+namespace patchpanel {
+
+constexpr uint32_t kMdnsMcastAddress = Ipv4Addr(224, 0, 0, 251);
+constexpr char kMdnsMcastAddress6[] = "ff02::fb";
+constexpr uint16_t kMdnsPort = 5353;
+constexpr uint32_t kSsdpMcastAddress = Ipv4Addr(239, 255, 255, 250);
+constexpr char kSsdpMcastAddress6[] = "ff02::c";
+constexpr uint16_t kSsdpPort = 1900;
+
+// Listens on a well-known port and forwards multicast messages between
+// network interfaces. Handles mDNS, legacy mDNS, and SSDP messages.
+// MulticastForwarder forwards multicast between 1 physical interface and
+// many guest interfaces.
+class MulticastForwarder {
+ public:
+ MulticastForwarder(const std::string& lan_ifname,
+ uint32_t mcast_addr,
+ const std::string& mcast_addr6,
+ uint16_t port);
+ virtual ~MulticastForwarder() = default;
+
+ // Start forwarding multicast packets between the guest's interface
+ // |int_ifname| and the external LAN interface |lan_ifname|. This
+ // only forwards traffic on multicast address |mcast_addr_| or
+ // |mcast_addr6_| and UDP port |port|.
+ bool AddGuest(const std::string& int_ifname);
+
+ // Stop forwarding multicast packets between |int_ifname| and
+ // |lan_ifname_|.
+ void RemoveGuest(const std::string& int_ifname);
+
+ // Rewrite mDNS A records pointing to |guest_ip| so that they point to
+ // the IPv4 |lan_ip| assigned to physical interface instead, so that Android
+ // can advertise services to devices on the LAN. This modifies |data|, an
+ // incoming packet that is |len| long.
+ static void TranslateMdnsIp(const struct in_addr& lan_ip,
+ const struct in_addr& guest_ip,
+ char* data,
+ ssize_t len);
+
+ protected:
+ // Socket is used to keep track of an fd and its watcher.
+ struct Socket {
+ Socket(base::ScopedFD fd,
+ sa_family_t sa_family,
+ const base::Callback<void(int, sa_family_t)>& callback);
+ base::ScopedFD fd;
+ std::unique_ptr<base::FileDescriptorWatcher::Controller> watcher;
+ };
+
+ // Bind will create a multicast socket and return its fd.
+ base::ScopedFD Bind(sa_family_t sa_family, const std::string& ifname);
+
+ // SendTo sends |data| using a socket bound to |src_port| and |lan_ifname_|.
+ // If |src_port| is equal to |port_|, we will use |lan_socket_|. Otherwise,
+ // create a temporary socket.
+ bool SendTo(uint16_t src_port,
+ const void* data,
+ ssize_t len,
+ const struct sockaddr* dst,
+ socklen_t dst_len);
+
+ // SendToGuests will forward packet to all Chrome OS guests' (ARC++,
+ // Crostini, etc) internal fd using |port|.
+ // However, if ignore_fd is not 0, it will skip guest with fd = ignore_fd.
+ bool SendToGuests(const void* data,
+ ssize_t len,
+ const struct sockaddr* dst,
+ socklen_t dst_len,
+ int ignore_fd = -1);
+
+ std::string lan_ifname_;
+ unsigned int port_;
+
+ struct in_addr mcast_addr_;
+ struct in6_addr mcast_addr6_;
+
+ std::map<sa_family_t, std::unique_ptr<Socket>> lan_socket_;
+
+ // Mapping from internal interface name to internal sockets.
+ std::map<std::pair<sa_family_t, std::string>, std::unique_ptr<Socket>>
+ int_sockets_;
+
+ // A set of internal file descriptors (guest facing sockets) to its guest
+ // IP address.
+ std::set<std::pair<sa_family_t, int>> int_fds_;
+
+ private:
+ void OnFileCanReadWithoutBlocking(int fd, sa_family_t sa_family);
+
+ DISALLOW_COPY_AND_ASSIGN(MulticastForwarder);
+};
+
+} // namespace patchpanel
+
+#endif // PATCHPANEL_MULTICAST_FORWARDER_H_