Refactor unix domain socket.

net/socket/unix_domain_server_socket_posix.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "net/socket/unix_domain_server_socket_posix.h"
+
+#include <errno.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <unistd.h>
+
+#include "base/logging.h"
+#include "net/base/net_errors.h"
+#include "net/socket/socket_libevent.h"
+#include "net/socket/unix_domain_client_socket_posix.h"
+
+namespace net {
+
+UnixDomainServerSocket::UnixDomainServerSocket(
+    const AuthCallback& auth_callback,
+    bool use_abstract_namespace)
+    : auth_callback_(auth_callback),
+      use_abstract_namespace_(use_abstract_namespace) {

[mmenke, 2014/07/10 19:07:28]

Maybe add DCHECK(!auth_callback_.is_null())?

[byungchul, 2014/07/11 02:56:33]

Done.

+}
+
+UnixDomainServerSocket::~UnixDomainServerSocket() {
+}
+
+// static
+bool UnixDomainServerSocket::GetPeerIds(SocketDescriptor socket,
+                                        uid_t* user_id,
+                                        gid_t* group_id) {
+#if defined(OS_LINUX) || defined(OS_ANDROID)
+  struct ucred user_cred;
+  socklen_t len = sizeof(user_cred);
+  if (getsockopt(socket, SOL_SOCKET, SO_PEERCRED, &user_cred, &len) < 0)
+    return false;
+  *user_id = user_cred.uid;
+  *group_id = user_cred.gid;
+#else
+  if (getpeereid(socket, user_id, group_id) < 0)
+    return false;
+#endif
+  return true;

[mmenke, 2014/07/10 19:07:28]

optional:  May be a little cleaner to keep the paths separate:

  return true;
#else
  return getpeereid(socket, user_id, group_id) >= 0;
#endif

[byungchul, 2014/07/11 02:56:33]

Done.

+}
+
+int UnixDomainServerSocket::Listen(const IPEndPoint& address, int backlog) {
+  NOTIMPLEMENTED();
+  return ERR_NOT_IMPLEMENTED;
+}
+
+int UnixDomainServerSocket::ListenWithAddressAndPort(
+    const std::string& unix_domain_path,
+    int port_unused,
+    int backlog) {
+  DCHECK(!listen_socket_);
+
+  SockaddrStorage address;
+  if (!UnixDomainClientSocket::FillAddress(unix_domain_path,
+                                           use_abstract_namespace_,
+                                           &address)) {
+    return ERR_ADDRESS_INVALID;
+  }
+
+  listen_socket_.reset(new SocketLibevent);
+  int rv = listen_socket_->Open(AF_UNIX);

[mmenke, 2014/07/10 19:07:28]

Maybe DCHECK_NE(ERR_IO_PENDING, rv);?

[byungchul, 2014/07/11 02:56:33]

Done.

+  if (rv != OK)
+    return rv;
+
+  rv = listen_socket_->Bind(address);
+  if (rv != OK) {
+    PLOG(ERROR)
+        << "Could not bind unix domain socket to " << unix_domain_path
+        << (use_abstract_namespace_ ? " (with abstract namespace)" : "");
+    return rv;
+  }
+
+  return listen_socket_->Listen(backlog);
+}
+
+int UnixDomainServerSocket::GetLocalAddress(IPEndPoint* address) const {
+  NOTIMPLEMENTED();
+  return ERR_NOT_IMPLEMENTED;
+}
+
+int UnixDomainServerSocket::Accept(scoped_ptr<StreamSocket>* socket,
+                                   const CompletionCallback& callback) {
+  DCHECK(socket);
+  DCHECK(!callback.is_null());
+  DCHECK(listen_socket_);
+  DCHECK(!accept_socket_);
+
+  while (true) {
+    int rv = listen_socket_->Accept(
+        &accept_socket_,
+        base::Bind(&UnixDomainServerSocket::AcceptCompleted,
+                   base::Unretained(this), socket, callback));
+    if (rv != OK)
+      return rv;
+    if (AuthenticateAndGetStreamSocket(socket))
+      return OK;
+  }
+}
+
+void UnixDomainServerSocket::AcceptCompleted(scoped_ptr<StreamSocket>* socket,
+                                             const CompletionCallback& callback,
+                                             int rv) {
+  if (rv != OK) {
+    callback.Run(rv);
+    return;
+  }
+
+  if (AuthenticateAndGetStreamSocket(socket)) {
+    callback.Run(OK);
+    return;
+  }

[mmenke, 2014/07/10 19:07:28]

Hrm...Don't see a clean way to avoid duplicating this code (The OK check and
subsequent call to AuthenticateAndGetStreamSocket).  Don't suppose you have any
ideas.

[byungchul, 2014/07/11 02:56:33]

Well, if rv != OK goes into AuthenticateAndGetStreamSocket() and returns true,
we can do that technically, but afraid it is less readable.

+
+  // Accepts another socket because authentication error should be transparent
+  // to the caller.
+  rv = Accept(socket, callback);
+  if (rv != ERR_IO_PENDING)
+    callback.Run(rv);
+}
+
+bool UnixDomainServerSocket::AuthenticateAndGetStreamSocket(
+    scoped_ptr<StreamSocket>* socket) {
+  DCHECK(accept_socket_);
+
+  uid_t user_id;
+  gid_t group_id;
+  if (!GetPeerIds(accept_socket_->socket_fd(), &user_id, &group_id) ||
+      !auth_callback_.Run(user_id, group_id)) {
+    accept_socket_.reset();
+    return false;
+  }
+
+  socket->reset(new UnixDomainClientSocket(accept_socket_.Pass()));
+  return true;
+}
+
+}  // namespace net