Merge "init: Add option to listen on sockets before starting service." into tm-qpr-dev

7 files changed, 22 insertions, 12 deletions

diff --git a/init/README.md b/init/README.md
index 13c6ebdfa..aaafe7887 100644
--- a/init/README.md
+++ b/init/README.md
@@ -352,9 +352,10 @@ runs the service.
 
 `socket <name> <type> <perm> [ <user> [ <group> [ <seclabel> ] ] ]`
 > Create a UNIX domain socket named /dev/socket/_name_ and pass its fd to the
-  launched process.  _type_ must be "dgram", "stream" or "seqpacket".  _type_
-  may end with "+passcred" to enable SO_PASSCRED on the socket. User and
-  group default to 0.  'seclabel' is the SELinux security context for the
+  launched process.  The socket is created synchronously when the service starts.
+  _type_ must be "dgram", "stream" or "seqpacket".  _type_ may end with "+passcred"
+  to enable SO_PASSCRED on the socket or "+listen" to synchronously make it a listening socket.
+  User and group default to 0.  'seclabel' is the SELinux security context for the
   socket.  It defaults to the service security context, as specified by
   seclabel or computed based on the service executable file security context.
   For native executables see libcutils android\_get\_control\_socket().
diff --git a/init/property_service.cpp b/init/property_service.cpp
index 9f7c21543..26341b196 100644
--- a/init/property_service.cpp
+++ b/init/property_service.cpp
@@ -1379,7 +1379,8 @@ void StartPropertyService(int* epoll_socket) {
     StartSendingMessages();
 
     if (auto result = CreateSocket(PROP_SERVICE_NAME, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK,
-                                   false, 0666, 0, 0, {});
+                                   /*passcred=*/false, /*should_listen=*/false, 0666, /*uid=*/0,
+                                   /*gid=*/0, /*socketcon=*/{});
         result.ok()) {
         property_set_fd = *result;
     } else {
diff --git a/init/service_parser.cpp b/init/service_parser.cpp
index 9e914ee7c..1ee309d98 100644
--- a/init/service_parser.cpp
+++ b/init/service_parser.cpp
@@ -434,11 +434,14 @@ Result<void> ServiceParser::ParseSocket(std::vector<std::string>&& args) {
                        << "' instead.";
     }
 
-    if (types.size() > 1) {
-        if (types.size() == 2 && types[1] == "passcred") {
+    for (size_t i = 1; i < types.size(); i++) {
+        if (types[i] == "passcred") {
             socket.passcred = true;
+        } else if (types[i] == "listen") {
+            socket.listen = true;
         } else {
-            return Error() << "Only 'passcred' may be used to modify the socket type";
+            return Error() << "Unknown socket type decoration '" << types[i]
+                           << "'. Known values are ['passcred', 'listen']";
         }
     }
 
diff --git a/init/service_utils.cpp b/init/service_utils.cpp
index eed5c65db..d19f5eef5 100644
--- a/init/service_utils.cpp
+++ b/init/service_utils.cpp
@@ -168,7 +168,8 @@ void Descriptor::Publish() const {
 
 Result<Descriptor> SocketDescriptor::Create(const std::string& global_context) const {
     const auto& socket_context = context.empty() ? global_context : context;
-    auto result = CreateSocket(name, type | SOCK_CLOEXEC, passcred, perm, uid, gid, socket_context);
+    auto result = CreateSocket(name, type | SOCK_CLOEXEC, passcred, listen, perm, uid, gid,
+                               socket_context);
     if (!result.ok()) {
         return result.error();
     }
diff --git a/init/service_utils.h b/init/service_utils.h
index 9b65dca74..65a2012ff 100644
--- a/init/service_utils.h
+++ b/init/service_utils.h
@@ -54,6 +54,7 @@ struct SocketDescriptor {
     int perm = 0;
     std::string context;
     bool passcred = false;
+    bool listen = false;
     bool persist = false;
 
     // Create() creates the named unix domain socket in /dev/socket and returns a Descriptor object.
diff --git a/init/util.cpp b/init/util.cpp
index d1e518b57..5b3a73c0d 100644
--- a/init/util.cpp
+++ b/init/util.cpp
@@ -86,8 +86,8 @@ Result<uid_t> DecodeUid(const std::string& name) {
  * daemon. We communicate the file descriptor's value via the environment
  * variable ANDROID_SOCKET_ENV_PREFIX<name> ("ANDROID_SOCKET_foo").
  */
-Result<int> CreateSocket(const std::string& name, int type, bool passcred, mode_t perm, uid_t uid,
-                         gid_t gid, const std::string& socketcon) {
+Result<int> CreateSocket(const std::string& name, int type, bool passcred, bool should_listen,
+                         mode_t perm, uid_t uid, gid_t gid, const std::string& socketcon) {
     if (!socketcon.empty()) {
         if (setsockcreatecon(socketcon.c_str()) == -1) {
             return ErrnoError() << "setsockcreatecon(\"" << socketcon << "\") failed";
@@ -142,6 +142,9 @@ Result<int> CreateSocket(const std::string& name, int type, bool passcred, mode_
     if (fchmodat(AT_FDCWD, addr.sun_path, perm, AT_SYMLINK_NOFOLLOW)) {
         return ErrnoError() << "Failed to fchmodat socket '" << addr.sun_path << "'";
     }
+    if (should_listen && listen(fd, /* use OS maximum */ 1 << 30)) {
+        return ErrnoError() << "Failed to listen on socket '" << addr.sun_path << "'";
+    }
 
     LOG(INFO) << "Created socket '" << addr.sun_path << "'"
               << ", mode " << std::oct << perm << std::dec
diff --git a/init/util.h b/init/util.h
index bf5367531..1e2eef090 100644
--- a/init/util.h
+++ b/init/util.h
@@ -44,8 +44,8 @@ static const char kColdBootDoneProp[] = "ro.cold_boot_done";
 
 extern void (*trigger_shutdown)(const std::string& command);
 
-Result<int> CreateSocket(const std::string& name, int type, bool passcred, mode_t perm, uid_t uid,
-                         gid_t gid, const std::string& socketcon);
+Result<int> CreateSocket(const std::string& name, int type, bool passcred, bool should_listen,
+                         mode_t perm, uid_t uid, gid_t gid, const std::string& socketcon);
 
 Result<std::string> ReadFile(const std::string& path);
 Result<void> WriteFile(const std::string& path, const std::string& content);