Return-Path: From: Szymon Janc To: Luiz Augusto von Dentz Cc: Marcel Holtmann , "linux-bluetooth@vger.kernel.org development" Subject: Re: [RFC 1/4] android: Add sample init.bluetooth.rc file Date: Fri, 17 Jan 2014 10:02:46 +0100 Message-ID: <2868864.nZFW2hpf5e@uw000953> In-Reply-To: References: <1389713283-13038-1-git-send-email-szymon.janc@tieto.com> <2728377.B2HgAZfSS5@uw000953> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" List-ID: Hi Luiz, On Friday 17 of January 2014 10:56:36 Luiz Augusto von Dentz wrote: > Hi Szymon, > > On Fri, Jan 17, 2014 at 10:34 AM, Szymon Janc wrote: > > Hi Marcel, > > > > On Tuesday 14 of January 2014 13:20:32 Marcel Holtmann wrote: > >> Hi Szymon, > >> > >> > This file is intended to be included from device init.rc. > >> > --- > >> > android/Android.mk | 16 +++++++++++++++- > >> > android/Makefile.am | 1 + > >> > android/init.bluetooth.rc | 27 +++++++++++++++++++++++++++ > >> > 3 files changed, 43 insertions(+), 1 deletion(-) > >> > create mode 100644 android/init.bluetooth.rc > >> > > >> > diff --git a/android/Android.mk b/android/Android.mk > >> > index ae52ab4..f13e703 100644 > >> > --- a/android/Android.mk > >> > +++ b/android/Android.mk > >> > @@ -109,7 +109,7 @@ LOCAL_MODULE := bluetooth.default > >> > LOCAL_MODULE_PATH := $(TARGET_OUT_SHARED_LIBRARIES)/hw > >> > LOCAL_MODULE_TAGS := optional > >> > LOCAL_MODULE_CLASS := SHARED_LIBRARIES > >> > -LOCAL_REQUIRED_MODULES := bluetoothd bluetoothd-snoop > >> > +LOCAL_REQUIRED_MODULES := bluetoothd bluetoothd-snoop init.bluetooth.rc > >> > > >> > include $(BUILD_SHARED_LIBRARY) > >> > > >> > @@ -263,3 +263,17 @@ LOCAL_MODULE_TAGS := optional > >> > LOCAL_MODULE := bluetoothd-snoop > >> > > >> > include $(BUILD_EXECUTABLE) > >> > + > >> > +# > >> > +# init.bleutooth.rc > >> > +# > >> > + > >> > +include $(CLEAR_VARS) > >> > + > >> > +LOCAL_MODULE := init.bluetooth.rc > >> > +LOCAL_MODULE_CLASS := ETC > >> > +LOCAL_SRC_FILES := $(LOCAL_MODULE) > >> > +LOCAL_MODULE_TAGS := optional > >> > +LOCAL_MODULE_PATH := $(TARGET_ROOT_OUT) > >> > + > >> > +include $(BUILD_PREBUILT) > >> > diff --git a/android/Makefile.am b/android/Makefile.am > >> > index 7806f79..b205019 100644 > >> > --- a/android/Makefile.am > >> > +++ b/android/Makefile.am > >> > @@ -134,6 +134,7 @@ android_audio_a2dp_default_la_LDFLAGS = $(AM_LDFLAGS) -module -avoid-version \ > >> > endif > >> > > >> > EXTRA_DIST += android/Android.mk android/hal-ipc-api.txt android/README \ > >> > + android/init.bluetooth.rc \ > >> > android/pics-gap.txt android/pics-hid.txt \ > >> > android/pics-pan.txt android/pics-did.txt \ > >> > android/pics-opp.txt android/pics-pbap.txt \ > >> > diff --git a/android/init.bluetooth.rc b/android/init.bluetooth.rc > >> > new file mode 100644 > >> > index 0000000..e2be9e8 > >> > --- /dev/null > >> > +++ b/android/init.bluetooth.rc > >> > @@ -0,0 +1,27 @@ > >> > +chown bluetooth bluetooth /data/misc/bluetooth > >> > + > >> > +chown bluetooth bluetooth /dev/uhid > >> > + > >> > +on property:bluetooth.start=bluetoothd > >> > + start bluetoothd > >> > + > >> > +on property:bluetooth.stop=bluetoothd > >> > + stop bluetoothd > >> > + > >> > +on property:bluetooth.start=bluetoothd-snoop > >> > + start bluetoothd-snoop > >> > + > >> > +on property:bluetooth.stop=bluetoothd-snoop > >> > + stop bluetoothd-snoop > >> > >> I think this is actually racy. The ctl.start and ctl.stop sound like they have special handling inside Android init. If you accidentally set bluetooth.start , then bad things happen. > > > > on property:foo=bar is also triggered if foo is already set to bar so I don't > > see what could happen wrong here. > > > >> > >> So I would propose doing bluetooth.daemon=on/off and bluetooth.snoop=on/off > >> > >> We just have to make sure that when bluetoothd or bluetoothd-snoop die unexpectedly that these properties get set back to off. > > > > I'm not sure if we are able to set properties back to proper state if service > > exited in such case (that would trigger loop in init). > > > > My idea was to use bluetooth.start/stop to start/stop (actually stop is needed > > only for bluetoothd-snoop service) service by bluetooth user (sort of "sudo" > > wrapper) but don't care about values in those props and if one want to use > > props to track service lifetime then just use init.svc.bluetoothd{-snoop} > > property. > > > >> > >> > + > >> > +service bluetoothd /system/bin/logwrapper /system/bin/bluetoothd > >> > + class main > >> > + group bluetooth net_admin > >> > + disabled > >> > + oneshot > >> > + > >> > +service bluetoothd-snoop /system/bin/bluetoothd-snoop > >> > + class main > >> > + group bluetooth net_admin > >> > + disabled > >> > + oneshot > >> > >> Does net_admin include CAP_NET_RAW actually or are we using some sort of patched module for this? > > > > I'm not sure, this was probably just copied from <4.2 android. Since we > > start as root and drop caps I think this can be removed. > > Iirc CAP_NET_RAW is not required by mgmt nor any other part of > bluetoothd for Android make use of raw sockets so it was dropped at > some point. As per comment in main.c we need this for bnep ioctl. -- Best regards, Szymon Janc