Merge pull request #330 from shadowsocks/unix-socket

Pass the file descriptor through unix domain socket

build.sh

@@ -8,7 +8,7 @@ try pushd src/main
 
 # Build
 try $ANDROID_NDK_HOME/ndk-build clean
-try $ANDROID_NDK_HOME/ndk-build
+try $ANDROID_NDK_HOME/ndk-build -j8
 
 # copy executables
 rm -rf assets/armeabi-v7a

project/plugins.sbt

@@ -1,6 +1,6 @@
 resolvers += Resolver.url("scalasbt releases", new URL("http://scalasbt.artifactoryonline.com/scalasbt/sbt-plugin-snapshots"))(Resolver.ivyStylePatterns)
 
-addSbtPlugin("com.hanhuy.sbt" % "android-sdk-plugin" % "1.4.0")
+addSbtPlugin("com.hanhuy.sbt" % "android-sdk-plugin" % "1.4.6")
 
 resolvers += Resolver.sbtPluginRepo("snapshots")
 

src/main/java/com/github/shadowsocks/System.java

@@ -45,4 +45,5 @@ public class System {
 
   public static native void exec(String cmd);
   public static native String getABI();
+  public static native int sendfd(int fd);
 }

src/main/jni/Android.mk

@@ -110,6 +110,21 @@ LOCAL_CFLAGS := -O2 -I$(LOCAL_PATH)/libevent \
 
 include $(BUILD_STATIC_LIBRARY)
 
+########################################################
+## libancillary
+########################################################
+
+include $(CLEAR_VARS)
+
+ANCILLARY_SOURCE := fd_recv.c fd_send.c
+
+LOCAL_MODULE := libancillary
+LOCAL_CFLAGS += -O2 -I$(LOCAL_PATH)/libancillary
+
+LOCAL_SRC_FILES := $(addprefix libancillary/, $(ANCILLARY_SOURCE))
+
+include $(BUILD_STATIC_LIBRARY)
+
 ########################################################
 ## libipset
 ########################################################
@@ -287,12 +302,13 @@ include $(CLEAR_VARS)
 
 LOCAL_MODULE:= system
 
-LOCAL_SRC_FILES:= \
-	   system.cpp
+LOCAL_C_INCLUDES:= $(LOCAL_PATH)/libancillary
+
+LOCAL_SRC_FILES:= system.cpp
 
 LOCAL_LDLIBS := -ldl -llog
 
-LOCAL_STATIC_LIBRARIES := cpufeatures
+LOCAL_STATIC_LIBRARIES := cpufeatures libancillary
 
 include $(BUILD_SHARED_LIBRARY)
 
@@ -309,7 +325,10 @@ LOCAL_CFLAGS += -DBADVPN_LITTLE_ENDIAN -DBADVPN_THREAD_SAFE
 LOCAL_CFLAGS += -DNDEBUG -DANDROID
 # LOCAL_CFLAGS += -DTUN2SOCKS_JNI
 
+LOCAL_STATIC_LIBRARIES := libancillary
+
 LOCAL_C_INCLUDES:= \
+		$(LOCAL_PATH)/libancillary \
         $(LOCAL_PATH)/badvpn/lwip/src/include/ipv4 \
         $(LOCAL_PATH)/badvpn/lwip/src/include/ipv6 \
         $(LOCAL_PATH)/badvpn/lwip/src/include \

src/main/jni/badvpn/tun2socks/tun2socks.c

@@ -71,9 +71,13 @@
 #include <generated/blog_channel_tun2socks.h>
 
 #ifdef ANDROID
+
+#include <ancillary.h>
+
 #include <sys/prctl.h>
 #include <sys/un.h>
 #include <structure/BAVL.h>
+
 BAVL connections_tree;
 typedef struct {
     BAddr local_addr;
@@ -408,7 +412,6 @@ int main (int argc, char **argv)
         prctl(PR_SET_NAME, "com.github.shadowsocks");
     }
 
-
     // handle --help and --version
     if (options.help) {
         print_version();
@@ -490,11 +493,56 @@ int main (int argc, char **argv)
 
 #ifdef ANDROID
     // use supplied file descriptor
+
+    int sock, fd;
+    struct sockaddr_un addr;
+
+    if ((sock = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) {
+        BLog(BLOG_ERROR, "socket() failed: %s (socket sock = %d)\n", strerror(errno), sock);
+        goto fail2;
+    }
+
+    char *path = "/data/data/com.github.shadowsocks/sock_path";
+    unlink(path);
+    memset(&addr, 0, sizeof(addr));
+    addr.sun_family = AF_UNIX;
+    strncpy(addr.sun_path, path, sizeof(addr.sun_path)-1);
+
+    if (bind(sock, (struct sockaddr*)&addr, sizeof(addr)) == -1) {
+        BLog(BLOG_ERROR, "bind() failed: %s (sock = %d)\n", strerror(errno), sock);
+        close(sock);
+        goto fail2;
+    }
+
+    if (listen(sock, 5) == -1) {
+        BLog(BLOG_ERROR, "listen() failed: %s (sock = %d)\n", strerror(errno), sock);
+        close(sock);
+        goto fail2;
+    }
+
+    for (;;) {
+        int sock2;
+        struct sockaddr_un remote;
+        int t = sizeof(remote);
+        if ((sock2 = accept(sock, (struct sockaddr *)&remote, &t)) == -1) { 
+            BLog(BLOG_ERROR, "accept() failed: %s (sock = %d)\n", strerror(errno), sock);
+            continue;
+        }
+        if (ancil_recv_fd(sock2, &fd)) {
+            BLog(BLOG_ERROR, "ancil_recv_fd: %s (sock = %d)\n", strerror(errno), sock2);
+            close(sock2);
+        } else {
+            close(sock2);
+            BLog(BLOG_INFO, "received fd = %d", fd);
+            break;
+        }
+    }
+    close(sock);
 
     struct BTap_init_data init_data;
     init_data.dev_type = BTAP_DEV_TUN;
     init_data.init_type = BTAP_INIT_FD;
-    init_data.init.fd.fd = options.tun_fd;
+    init_data.init.fd.fd = fd;
     init_data.init.fd.mtu = options.tun_mtu;
 
     if (!BTap_Init2(&device, &ss, init_data, device_error_handler, NULL)) {

src/main/jni/libancillary/API

@@ -0,0 +1,139 @@
+  This library provide an easy interface to the black magic that can be done
+  on Unix domain sockets, like passing file descriptors from one process to
+  another.
+
+  Programs that uses this library should include the ancillary.h header file.
+  Nothing else is required.
+
+  All functions of this library require the following header:
+
+	#include <ancillary.h>
+
+  At this time, the only ancillary data defined by the Single Unix
+  Specification (v3) is file descriptors.
+
+Passing file descriptors
+
+	int ancil_send_fd(socket, file_descriptor)
+	  int socket: the Unix socket
+	  int file_descriptor: the file descriptor
+	  Return value: 0 for success, -1 for failure.
+
+  Sends one file descriptor on a socket.
+  In case of failure, errno is set; the possible values are the ones of the
+  sendmsg(2) system call.
+
+
+	int ancil_recv_fd(socket, file_descriptor)
+	  int socket: the Unix socket
+	  int *file_descriptor: pointer to the returned file descriptor
+	  Return value: 0 for success, -1 for failure
+
+  Receives one file descriptor from a socket.
+  In case of success, the file descriptor is stored in the integer pointed
+  to by file_descriptor.
+  In case of failure, errno is set; the possible values are the ones of the
+  recvmsg(2) system call.
+  The behavior is undefined if the recv_fd does not match a send_fd* on the
+  other side.
+
+
+	int ancil_send_fds(socket, file_descriptors, num_file_descriptors)
+	  int socket: the Unix socket
+	  const int *file_descriptors: array of file descriptors
+	  unsigned num_file_descriptors: number of file descriptors
+	  Return value: 0 for success, -1 for failure
+
+  Sends several file descriptors on a socket.
+  In case of failure, errno is set; the possible values are the ones of the
+  sendmsg(2) system call.
+  The maximum number of file descriptors that can be sent using this
+  function is ANCIL_MAX_N_FDS; the behavior is undefined in case of
+  overflow, probably a stack corruption.
+
+
+	int ancil_recv_fds(socket, file_descriptors, num_file_descriptors)
+	  int socket: the Unix socket
+	  int *file_descriptors: return array of file descriptors
+	  unsigned num_file_descriptors: number of file descriptors
+	  Return value: number of received fd for success, -1 for failure
+
+  Receives several file descriptors from a socket, no more than
+  num_file_descriptors.
+  In case of success, the received file descriptors are stored in the array
+  pointed to by file_descriptors.
+  In case of failure, errno is set; the possible values are the ones of the
+  recvmsg(2) system call.
+  The maximum number of file descriptors that can be received using this
+  function is ANCIL_MAX_N_FDS; the behavior is undefined in case of
+  overflow, probably a stack corruption.
+  The behavior is undefined if the recv_fds does not match a send_fd* on
+  the other side, or if the number of received file descriptors is more than
+  num_file_descriptors.
+
+
+	int ancil_send_fds_with_buffer(socket, fds, num, buffer)
+	  int socket: the Unix socket
+	  const int *fds: array of file descriptors
+	  unsigned num: number of file descriptors
+	  void *buffer: buffer to hold the system data structures
+	  Return value: 0 for success, -1 for failure
+
+  Sends several file descriptors on a socket.
+  In case of failure, errno is set; the possible values are the ones of the
+  sendmsg(2) system call.
+  The buffer argument must point to a memory area large enough to hold the
+  system data structures, see ANCIL_FD_BUFFER.
+
+
+	int ancil_send_fds_with_buffer(socket, fds, num, buffer)
+	  int socket: the Unix socket
+	  int *fds: return array of file descriptors
+	  unsigned num: number of file descriptors
+	  void *buffer: buffer to hold the system data structures
+	  Return value: number of received fd for success, -1 for failure
+
+  Receives several file descriptors from a socket, no more than
+  num_file_descriptors.
+  In case of success, the received file descriptors are stored in the array
+  pointed to by file_descriptors.
+  In case of failure, errno is set; the possible values are the ones of the
+  recvmsg(2) system call.
+  The behavior is undefined if the recv_fds does not match a send_fd* on
+  the other side, or if the number of received file descriptors is more than
+  num_file_descriptors.
+  The buffer argument must point to a memory area large enough to hold the
+  system data structures, see ANCIL_FD_BUFFER.
+
+
+	ANCIL_MAX_N_FDS
+
+  Maximum number of file descriptors that can be sent with the sent_fds and
+  recv_fds functions. If you have to send more at once, use the
+  *_with_buffer versions. The value is enough to send "quite a few" file
+  descriptors.
+
+
+	ANCIL_FD_BUFFER(n)
+	  int n: number of file descriptors
+
+  Expands to a structure data type large enough to hold the system data
+  structures for n file descriptors. So the address of a variable declared
+  of type ANCIL_FD_BUFFER(n) is suitable as the buffer argument for
+  *_with_buffer on n file descriptors.
+  To use this macro, you need <sys/types.h> and <sys/socket.h>. Bevare: with
+  Solaris, the _XPG4_2 macro must be defined before sys/socket is included.
+
+
+Tuning the compilation
+
+  This library is designed to be included in projects, not installed in
+  /usr/lib. If your project does not use some of the functions, the
+  TUNE_OPTS variable in the Makefile allows not to build them. It is a list
+  of proprocessor options:
+
+  -DNDEBUG: turn assertions off (see assert(3))
+  -DSPARE_SEND_FDS: do not build ancil_send_fds
+  -DSPARE_SEND_FD:  do not build ancil_send_fd
+  -DSPARE_RECV_FDS: do not build ancil_recv_fds
+  -DSPARE_RECV_FD:  do not build ancil_recv_fd

src/main/jni/libancillary/COPYING

@@ -0,0 +1,21 @@
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+ 1. Redistributions of source code must retain the above copyright notice,
+    this list of conditions and the following disclaimer.
+ 2. Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in the
+    documentation and/or other materials provided with the distribution.
+ 3. The name of the author may not be used to endorse or promote products
+    derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
+EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

src/main/jni/libancillary/Makefile

@@ -0,0 +1,73 @@
+###########################################################################
+# libancillary - black magic on Unix domain sockets
+# (C) Nicolas George
+# Makefile - guess what
+###########################################################################
+
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# 
+#  1. Redistributions of source code must retain the above copyright notice,
+#     this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. The name of the author may not be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+# WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+# MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
+# EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+# OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+# WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+# OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+# ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+CC=gcc
+CFLAGS=-Wall -g -O2
+LDFLAGS=
+LIBS=
+AR=ar
+RANLIB=ranlib
+RM=rm
+CP=cp
+MKDIR=mkdir
+TAR=tar
+GZIP=gzip -9
+
+NAME=libancillary
+DISTRIBUTION=API COPYING Makefile ancillary.h fd_send.c fd_recv.c test.c
+VERSION=0.9.1
+
+OBJECTS=fd_send.o fd_recv.o
+
+TUNE_OPTS=-DNDEBUG
+#TUNE_OPTS=-DNDEBUG \
+	-DSPARE_SEND_FDS -DSPARE_SEND_FD -DSPARE_RECV_FDS -DSPARE_RECV_FD
+
+.c.o:
+	$(CC) -c $(CFLAGS) $(TUNE_OPTS) $<
+
+all: libancillary.a
+
+libancillary.a: $(OBJECTS)
+	$(AR) cr $@ $(OBJECTS)
+	$(RANLIB) $@
+
+fd_send.o: ancillary.h
+fd_recv.o: ancillary.h
+
+test: test.c libancillary.a
+	$(CC) -o $@ $(CFLAGS) $(LDFLAGS) -L. test.c -lancillary $(LIBS)
+
+clean:
+	-$(RM) -f *.o *.a test 
+
+dist:
+	$(MKDIR) $(NAME)-$(VERSION)
+	$(CP) $(DISTRIBUTION) $(NAME)-$(VERSION)
+	$(TAR) -cf - $(NAME)-$(VERSION) | $(GZIP) > $(NAME)-$(VERSION).tar.gz
+	$(RM) -rf $(NAME)-$(VERSION)