IC_src/mtk/framework/lynq-ndis-uevent/src/main.cpp

/*@file lynq-ndis-uevent.c 
* @brief adb default port is closed, The uevent event of NDIS is reported to switch port.
* @author dongyu
* @date 2022-10-14
* @version V1.0
* @copyright MobileTek
*/

#include <stdio.h>
#include <string.h>
#include <sys/socket.h>
#include <linux/netlink.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include <include/lynq_uci.h>

#define _GNU_SOURCE
#define UEVENT_MSG_LEN 1024

#define LOG_UCI_FILE "lynq_uci"
#define LOG_UCI_MODULE "lynq_rndis"

int rndis_initiate_mode = 0;

struct uevent{
    const char *action;
    const char *path;
    const char *subsystem;
    const char *firmware;
    const char *calluser;
    int major;
    int minor;
};

static int lynq_open_uevent_socket(void)
{
    struct sockaddr_nl addr;
    int sz = 64*1024;
    int on = 1;
    int socketfd;

    memset(&addr, 0, sizeof(addr));
    addr.nl_family = AF_NETLINK;
    addr.nl_pid = getpid();
    addr.nl_groups = 0xffffffff;

    socketfd = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);
    if(socketfd < 0){
        return -1;
    }

    setsockopt(socketfd, SOL_SOCKET, SO_RCVBUFFORCE, &sz, sizeof(sz));
    setsockopt(socketfd, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on));

    if(bind(socketfd, (struct sockaddr *) &addr, sizeof(addr)) < 0){
        close(socketfd);
        return -1;
    }

    return socketfd;
}

static void lynq_parse_event(const char *msg, struct uevent *uevent)
{
    uevent->action = "";
    uevent->path = "";
    uevent->subsystem = "";
    uevent->firmware = "";
    uevent->calluser = "";
    uevent->major = -1;
    uevent->minor = -1;

    /* currently ignoring SEQNUM */
    while(*msg){
        printf("%s\n", msg);
        if(!strncmp(msg, "ACTION=", 7)){
            msg += 7;
            uevent->action = msg;
        } else if(!strncmp(msg, "DEVPATH=", 8)){
            msg += 8;
            uevent->path = msg;
        } else if(!strncmp(msg, "SUBSYSTEM=", 10)){
            msg += 10;
            uevent->subsystem = msg;
        } else if(!strncmp(msg, "FIRMWARE=", 9)){
            msg += 9;
            uevent->firmware = msg;
        } else if(!strncmp(msg, "MAJOR=", 6)){
            msg += 6;
            uevent->major = atoi(msg);
        } else if(!strncmp(msg, "MINOR=", 6)){
            msg += 6;
            uevent->minor = atoi(msg);
        } else if(!strncmp(msg, "CALL_USER=", 10)){
            msg += 10;
            uevent->calluser = msg;
        }

        /* advance to after the next \0 */
        while(*msg++);
    }

    printf("event { '%s', '%s', '%s', '%s', %d, %d }\n",
        uevent->action, uevent->path, uevent->subsystem,
        uevent->firmware, uevent->major, uevent->minor);
}

void lynq_handle_device_fd(int fd)
{
    printf("enter %s\n", __func__);
    for(;;) {
        char msg[UEVENT_MSG_LEN+2];
        char cred_msg[CMSG_SPACE(sizeof(struct ucred))];
        struct iovec iov = {msg, sizeof(msg)};
        struct sockaddr_nl snl;
        struct msghdr hdr = {&snl, sizeof(snl), &iov, 1, cred_msg, sizeof(cred_msg), 0};

        ssize_t n = recvmsg(fd, &hdr, 0);
        if (n <= 0){
            break;
        }

        if ((snl.nl_groups != 1) || (snl.nl_pid != 0)){
            /* ignoring non-kernel netlink multicast message */
            continue;
        }

        struct cmsghdr * cmsg = CMSG_FIRSTHDR(&hdr);
        if (cmsg == NULL || cmsg->cmsg_type != SCM_CREDENTIALS){
            /* no sender credentials received, ignore message */
            continue;
        }

        struct ucred * cred = (struct ucred *)CMSG_DATA(cmsg);
        if (cred->uid != 0){
            /* message from non-root user, ignore */
            continue;
        }

        if(n >= UEVENT_MSG_LEN){
            /* overflow -- discard */
            continue;
        }

        msg[n] = '\0';
        msg[n+1] = '\0';
 
        printf("2022 ::: msg =  %s\n", msg);
        struct uevent uevent;
        lynq_parse_event(msg, &uevent);

        if(strcmp(uevent.path,"/devices/virtual/android_usb/android0") == 0
            && strcmp(uevent.calluser, "/usr/bin/usb uevent reporting") == 0){
            system("/usr/bin/usb_switch ets");
            printf("USB login port switch successfully!\n");
            while(1){
                sleep(1);
            }
        }
    }
}

int main(void)
{
    int fd = 0;
    char tmp[20];

    fd = lynq_open_uevent_socket();
    if (fd < 0){
        printf("error!\n");
        return -1;
    }

    lynq_get_value(LOG_UCI_FILE, LOG_UCI_MODULE, "initiate", tmp);
    rndis_initiate_mode=atoi(tmp);
    if(rndis_initiate_mode == 1){
        lynq_handle_device_fd(fd);
        while(1){
            sleep(1);
        }
    }
    else{
        while(1){
            sleep(1);
        }
    }
    return 0;
}