Question

我有commad-line工具，它发送广播和等待结果。

服务器代码（省略错误处理）：

    int makeAddr(const char* name, struct sockaddr_un* pAddr, socklen_t* pSockLen)
    {
        int nameLen = strlen(name);
        pAddr->sun_path[0] = '\0';
        strcpy(pAddr->sun_path+1, name);
        pAddr->sun_family = AF_LOCAL;
        *pSockLen = 1 + nameLen + offsetof(struct sockaddr_un, sun_path);
        return 0;
    }

    int main(int argc, char* argv[])
    {
        //...

        // Create socket in abstract namespace
        struct sockaddr_un sockAddr = {0};
        socklen_t sockLen;
        makeAddr("SOCKET_NAME", &sockAddr, &sockLen);

        int serverFd = socket(AF_LOCAL, SOCK_STREAM, PF_UNIX));

        bind(serverFd, (const struct sockaddr*) &sockAddr, sockLen);

        listen(serverFd, 5);

        //set socket non-blocking
        int flags = fcntl(serverFd, F_GETFL, 0);
        fcntl(serverFd, F_SETFL, flags | O_NONBLOCK);

        pollfd pollFd = {0};
        pollFd.fd = serverFd;
        pollFd.events = POLLIN | POLLRDHUP;

        // Send brodcast 
        system("am broadcast ...");

        for(;;)
        {
            // Wait result 
            int pollResult = poll(&pollFd, 1, timeout);
        // Process result

Java客户端代码：

public class CommandReceiver extends BroadcastReceiver{

    @Override
    public void onReceive(Context context, Intent intent) {

            LocalSocket socket = new LocalSocket();
            LocalSocketAddress address = new LocalSocketAddress("SOCKET_NAME", LocalSocketAddress.Namespace.ABSTRACT);
            socket.connect(address);

            // Do something and send result asynchronously

这一切都适用于Android之前的5.1。

在android 5.1上，connect（）抛出异常：

java.io.IOException：Permission denied

在android.net.LocalSocketImpl.connectLocal（原生方法）

在android.net.LocalSocketImpl.connect（LocalSocketImpl.java:290）

在android.net.LocalSocket.connect（LocalSocket.java:130）

在日志中有错误：

07-27 09：56：08.179：W：type = 1400 audit（0.0：3675）：avc：拒绝{connectto} for path = 00636F6D2E6B6173706572736B792E6B617368656C6C2E534F434B45542D36313838363731373231343337393833373637 scontext = u：r：untrusted_app：s0 tcontext = u：r：shell ：s0 tclass = unix_stream_socket permissive = 0

我发现了相对的android修复： https://android.googlesource.com/device/moto/shamu/+/b2db40f

那么，自从Android 5.1以后它将不再起作用了？我能做些什么（可能以某种方式设置权限）？或者是否有另一种机制从本机命令行工具发送数据并等待结果？

Answer 1

使用管道代替套接字： O_RDWR on named pipes with poll()

在java进程中创建管道：

        mkfifo(cpath, 0);
        chmod(cpath, S_IRWXU|S_IROTH|S_IRGRP);

在本机进程中打开管道：

int serverFd = open(PIPE_NAME, O_RDONLY | O_NONBLOCK);
pollfd pollFd = {0};
pollFd.fd = serverFd.get();
pollFd.events = POLLIN | POLLRDHUP;

// send command
....

for(;;)
{
    int pollResult = poll(&pollFd, 1, timeout);

无法连接到Android 5.1上的本机本地套接字

1 个答案: