antd-tunnel-plugin/tunnel.c

#define PLUGIN_IMPLEMENT 1
#include <stdlib.h>
#include <errno.h>
#include <unistd.h>
#include <stdio.h>
#include <termios.h>
#include <string.h>
#include <antd/plugin.h>
#include <semaphore.h>
#include <pthread.h>
#include <sys/socket.h>
#include <sys/un.h>

#include "bst.h"
#define MAX_CHANNEL_PATH            108
#define MAX_CHANNEL_NAME            64
#define HOT_LINE_SOCKET             "antd_hotline.sock"
#define SOCK_DIR_NAME               "channels"
#define MSG_MAGIC_BEGIN             0x414e5444 //ANTD
#define MSG_MAGIC_END               0x44544e41 //DTNA
#define SELECT_TIMEOUT              300 // ms

#define    CHANNEL_OK               (uint8_t)0x0
#define    CHANNEL_ERROR            (uint8_t)0x1
#define    CHANNEL_SUBSCRIBE        (uint8_t)0x2
#define    CHANNEL_UNSUBSCRIBE      (uint8_t)0x3
#define    CHANNEL_OPEN             (uint8_t)0x4
#define    CHANNEL_CLOSE            (uint8_t)0x5
#define    CHANNEL_DATA             (uint8_t)0x6
//#define    CHANNEL_LIST             (uint8_t)0x7
typedef struct {
    int sock;
    char sun_path[MAX_CHANNEL_PATH];
    char name[MAX_CHANNEL_NAME];
    bst_node_t* subscribers;
} antd_tunnel_channel_t;

typedef struct {
    uint8_t type;
    int channel_id;
    int client_id;
    int size;
} antd_tunnel_msg_h_t;

typedef struct{
    antd_tunnel_msg_h_t header;
    uint8_t data;
} antd_tunnel_msg_t;
/**
 * Message is sent in the following format
 * |BEGIN MAGIC(4)|MSG TYPE(1)| CHANNEL ID (4)| CLIENT ID (4)| data length (4)| data(m) | END MAGIC(4)|
 */

typedef struct {
    pthread_mutex_t lock;
    bst_node_t* channels;
    pthread_t tid;
    int hotline;
    uint32_t id_allocator;
} antd_tunnel_t;

static antd_tunnel_t g_tunnel;


static int mk_socket(const char* name, char* path)
{
    struct sockaddr_un address;
    address.sun_family = AF_UNIX;
    // create the socket
    (void)snprintf(path, MAX_CHANNEL_PATH,"%s/%s/",__plugin__.tmpdir, SOCK_DIR_NAME);

    if(!_exist(path))
    {
        LOG("Socket dir does not exist, create it: %s",path);
        if(mkdir(path, 0700) == -1)
        {
            ERROR("Unable to create socket dir: %s =", strerror(errno));
            return -1;
        }
    }
    
    // Append the name of the socket
    if(strlen(path) + strlen(name) > MAX_CHANNEL_PATH)
    {
        ERROR("Socket file path exceeds the maximal size of: %d", MAX_CHANNEL_PATH);
        return -1;
    }
    (void)strcat(path, HOT_LINE_SOCKET);


    (void) strncpy(address.sun_path, path, sizeof(address.sun_path));
    int fd = socket(AF_UNIX, SOCK_STREAM, 0);
    if(fd == -1)
    {
        ERROR("Unable to create Unix domain socket: %s", strerror(errno));
        return -1;
    }
    if(bind(fd, (struct sockaddr*)(&address), sizeof(address)) == -1)
    {
        ERROR("Unable to bind name: %s to a socket: %s", address.sun_path, strerror(errno));
        return -1;
    }
    // mark the socket as passive mode
    if(listen(fd , 100) == -1)
    {
        ERROR("Unable to listen to socket: %d (%s): %s",fd, path , strerror(errno));
        return -1;
    }
    LOG("Socket %s is created successfully", path);
    return fd;
}

static int msg_check_number(int fd, int number)
{
    int value;
    if(read(fd,&value,sizeof(value)) == -1)
    {
        ERROR("Unable to read integer value: %s", strerror(errno));
        return -1;
    }
    if(number != value)
    {
        ERROR("Value mismatches: %0x%04X, expected %0x%04X", value, number);
        return -1;
    }
    return 0;
}
static int msg_read_string(int fd, char* buffer, uint8_t max_length)
{
    uint8_t size;
    if(read(fd,&size,sizeof(size)) == -1)
    {
        ERROR("Unable to read string size: %s", strerror(errno));
        return -1;
    }
    if(size > max_length)
    {
        ERROR("String length exceeds the maximal value of ", max_length);
        return -1;
    }
    if(read(fd,buffer,size) == -1)
    {
        ERROR("Unable to read string to buffer: %s", strerror(errno));
        return -1;
    }
    return 0;
}

static char* msg_read_payload(int fd, int* size)
{
    char* data;
    if(read(fd,size,sizeof(*size)) == -1)
    {
        ERROR("Unable to read payload data size: %s", strerror(errno));
        return NULL;
    }
    if(size <= 0)
    {
        return NULL;
    }

    data = (char*) malloc(*size);
    if(data == NULL)
    {
        ERROR("Unable to allocate memory for payload data: %s", strerror(errno));
        return NULL;
    }
    if(read(fd,data,*size) == -1)
    {
        ERROR("Unable to read payload data to buffer: %s", strerror(errno));
        free(data);
        return NULL;
    }
    return data;
}

static int msg_read(int fd, antd_tunnel_msg_t* msg)
{
    if(msg_check_number(fd, MSG_MAGIC_BEGIN) == -1)
    {
        ERROR("Unable to check begin magic number");
        return -1;
    }
    if(read(fd,&msg->header.type,sizeof(msg->header.type)) == -1)
    {
        ERROR("Unable to read msg type: %s", strerror(errno));
        return -1;
    }
    if(msg->header.type > 0x6)
    {
        ERROR("Unknown msg type: %d", msg->header.type);
        return -1;
    }
    if(read(fd, &msg->header.channel_id, sizeof(msg->header.channel_id)) == -1)
    {
        ERROR("Unable to read msg channel id");
        return -1;
    }
    if(read(fd, &msg->header.client_id, sizeof(msg->header.client_id)) == -1)
    {
        ERROR("Unable to read msg client id");
        return -1;
    }
    if((msg->data = msg_read_payload(fd, &msg->header.size)) == NULL)
    {
        ERROR("Unable to read msg payload data");
        return -1;
    }
    if(msg_check_number(fd, MSG_MAGIC_END) == -1)
    {
        if(msg->data)
        {
            free(msg->data);
        }
        ERROR("Unable to check end magic number");
        return -1;
    }
    return 0;
}

static int msg_write(int fd, antd_tunnel_msg_t* msg)
{
    // write begin magic number
    int number = MSG_MAGIC_BEGIN;
    if(write(fd,&number, sizeof(number)) == -1)
    {
        ERROR("Unable to write begin magic number: %s", strerror(errno));
        return -1;
    }
    // write type
    if(write(fd,&msg->header.type, sizeof(msg->header.type)) == -1)
    {
        ERROR("Unable to write msg type: %s", strerror(errno));
        return -1;
    }
    // write channel id
    if(write(fd,&msg->header.channel_id, sizeof(msg->header.channel_id)) == -1)
    {
        ERROR("Unable to write msg channel id: %s", strerror(errno));
        return -1;
    }
    //write client id
    if(write(fd,&msg->header.client_id, sizeof(msg->header.client_id)) == -1)
    {
        ERROR("Unable to write msg client id: %s", strerror(errno));
        return -1;
    }
    // write payload len
    if(write(fd,&msg->header.size, sizeof(msg->header.size)) == -1)
    {
        ERROR("Unable to write msg payload length: %s", strerror(errno));
        return -1;
    }
    // write payload data
    if(msg->header.size > 0)
    {
        if(write(fd,msg->data, msg->header.size) == -1)
        {
            ERROR("Unable to write msg payload: %s", strerror(errno));
            return -1;
        }
    }
    number = MSG_MAGIC_END;
    if(write(fd,&number, sizeof(number)) == -1)
    {
        ERROR("Unable to write end magic number: %s", strerror(errno));
        return -1;
    }
    return 0;
}
static void destroy_channel(antd_tunnel_channel_t* channel)
{
    if(channel->sock != -1)
    {
        (void) close(channel->sock);
        (void)unlink(channel->sun_path);
    }
    /** TODO: send message to all subcribers before close*/
    bst_free(channel->subscribers);
}
static void channel_open(int fd, const char* name)
{
    char buffer[BUFFLEN];
    antd_tunnel_channel_t* channel = NULL;
    bst_node_t* node;
    int hash_val = simple_hash(name);
    antd_tunnel_msg_t msg;
    msg.data = buffer;
    msg.header.channel_id = 0;
    msg.header.client_id = 0;
    // look if the channel is already opened
    if(g_tunnel.channels != NULL)
    {
        pthread_mutex_lock(&g_tunnel.lock);
        node = bst_find(g_tunnel.channels, hash_val);
        pthread_mutex_unlock(&g_tunnel.lock);
        if(node != NULL)
        {
            snprintf(buffer, BUFFLEN, "Cannot open new channel: channel %s exists", name);
            LOG("%s", buffer);
            msg.header.type = CHANNEL_ERROR;
            msg.header.size = strlen(buffer);
            if(msg_write(fd, &msg) == -1)
            {
                ERROR("Unable to write message to hotline");
            }
            return;
        }
    }
    // create new channel
    channel = (antd_tunnel_channel_t*)malloc(sizeof(antd_tunnel_channel_t));
    if(channel == NULL)
    {
        snprintf(buffer, BUFFLEN, "Unable to allocate new memory for new channel");
        LOG("%s", buffer);
        msg.header.type = CHANNEL_ERROR;
        msg.header.size = strlen(buffer);
        if(msg_write(fd, &msg) == -1)
        {
            ERROR("Unable to write message to hotline");
        }
        return;
    }
    // create socket file
    (void)strncpy(channel->name, name, MAX_CHANNEL_NAME);
    channel->sock = mk_socket(name, channel->sun_path);
    if(channel->sock == -1)
    {
        snprintf(buffer, BUFFLEN, "Unable to create socket");
        msg.header.type = CHANNEL_ERROR;
        msg.header.size = strlen(buffer);
        free(channel);
        if(msg_write(fd, &msg) == -1)
        {
            ERROR("Unable to write message to hotline");
        }
        return;
    }
    // response with ok message
    msg.header.type = CHANNEL_OK;
    msg.header.channel_id = hash_val;
    msg.header.size = strlen(channel->sun_path);
    msg.data = channel->sun_path;
    if(msg_write(fd, &msg) == -1)
    {
        destroy_channel(channel);
        ERROR("Unable to write message to hotline");
    }
    // channel created
    pthread_mutex_lock(&g_tunnel.lock);
    g_tunnel.channels = bst_insert(g_tunnel.channels, hash_val, (void*) channel);
    pthread_mutex_unlock(&g_tunnel.lock);
}

static void channel_close(int fd, const char* name)
{
    char buffer[BUFFLEN];
    antd_tunnel_msg_t msg;
    bst_node_t* node;
    int hash_val = simple_hash(name);

    msg.data = buffer;
    msg.header.channel_id = 0;
    msg.header.client_id = 0;
    // look for the channel
    if(g_tunnel.channels != NULL)
    {
        pthread_mutex_lock(&g_tunnel.lock);
        node = bst_find(g_tunnel.channels, hash_val);
        if(node)
        {
            destroy_channel((antd_tunnel_channel_t*)node->data);
        }
        msg.header.channel_id = node->key;
        g_tunnel.channels = bst_delete(g_tunnel.channels, node->key);
        pthread_mutex_unlock(&g_tunnel.lock);
    }
    msg.header.type = CHANNEL_OK;
    msg.header.size = 0;
    if(msg_write(g_tunnel.hotline, &msg) == -1)
    {
        ERROR("Unable to write message to hotline");
    }
}
static void monitor_hotline(int fd)
{
    char buff[MAX_CHANNEL_NAME+1];
    antd_tunnel_msg_t msg;
    if(msg_read(fd, &msg) == -1)
    {
        ERROR("Unable to read message from hotline");
        return;
    }
    switch (msg.header.type)
    {
    case CHANNEL_OPEN:
    case CHANNEL_CLOSE:
        // get channel name
        if(msg.header.size > MAX_CHANNEL_NAME)
        {
            if(msg.data)
                free(msg.data);
            msg.header.type = CHANNEL_ERROR;
            (void) snprintf(buff, MAX_CHANNEL_NAME, "Channel name exceeds %d bytes", MAX_CHANNEL_NAME);
            LOG("%s", buff);
            msg.header.size = strlen(buff);
            msg.data = buff;
            if(msg_write(fd, &msg) == -1)
            {
                ERROR("Unable to write error to hotline");
            }
        }
        else
        {
            (void)memcpy(buff, msg.data, msg.header.size);
            buff[msg.header.size] = '\0';
            if(msg.header.type == CHANNEL_OPEN)
            {
                channel_open(fd, buff);
            }
            else
            {
                channel_close(fd, buff);
            }
        }
        break;

    default:
        msg.header.type = CHANNEL_ERROR;
        (void) snprintf(buff, MAX_CHANNEL_NAME, "Unsupported msg type %d in hotline", (int)msg.header.type);
        msg.header.size = strlen(buff);
        msg.data = buff;
        LOG("%s", buff);
        if(msg_write(fd, &msg) == -1)
        {
            ERROR("Unable to write error to hotline");
        }
        break;
    }
}
static void write_msg_to_client(antd_tunnel_msg_t* msg, antd_client_t* client)
{
    uint8_t* buffer;
    int long_value = 0;
    int offset = 0;
    long_value = msg->header.size +
            sizeof((int)MSG_MAGIC_BEGIN) +
            sizeof(msg->header.type) +
            sizeof(msg->header.channel_id) +
            sizeof(msg->header.client_id) +
            sizeof(msg->header.size) +
            msg->header.size +
            sizeof((int)MSG_MAGIC_END);
    buffer = (uint8_t*) malloc(long_value);
    if(buffer == NULL)
    {
        ERROR("unable to allocate memory for write");
        return;
    }
    // magic
    long_value = (int) MSG_MAGIC_BEGIN;
    (void)memcpy(buffer,&long_value,sizeof(long_value));
    offset += sizeof(long_value);
    
    // type
    (void)memcpy(buffer+offset,&msg->header.type,sizeof(msg->header.type));
    offset += sizeof(msg->header.type);

    // channel id
    (void)memcpy(buffer+offset,&msg->header.channel_id,sizeof(msg->header.channel_id));
    offset += sizeof(msg->header.channel_id);

    // client id
    (void)memcpy(buffer+offset,&msg->header.client_id,sizeof(msg->header.client_id));
    offset += sizeof(msg->header.client_id);

    // payload length
    (void)memcpy(buffer+offset,&msg->header.size,sizeof(msg->header.size));
    offset += sizeof(msg->header.size);

    // payload
    (void)memcpy(buffer+offset,&msg->data,sizeof(msg->header.size));
    offset += msg->header.size;

    // magic end
    long_value = (int) MSG_MAGIC_END;
    (void)memcpy(buffer,&long_value,sizeof(long_value));
    offset += sizeof(long_value);

    // write it to the websocket
    ws_b(client,buffer, offset);

    free(buffer);

}
static void handle_channel(bst_node_t* node, void** args, int argc)
{
    antd_tunnel_msg_t msg;
    (void) argc;
    fd_set* fd_in = (fd_set*) args[0];
    antd_tunnel_channel_t* channel = (antd_tunnel_channel_t*) node->data;
    bst_node_t * client;
    antd_client_t* rq;
    if(channel->sock != -1 && FD_ISSET(channel->sock, fd_in))
    {
        // handle msg read
        if(msg_read(channel->sock, &msg) == -1)
        {
            ERROR("Unable to read message from hotline");
            return;
        }
        switch (msg.header.type)
        {
            case CHANNEL_OK:
            case CHANNEL_ERROR:
            case CHANNEL_DATA:
                // forward message to the correct client in the channel
                client = bst_find(channel->subscribers, msg.header.client_id);
                if(client != NULL)
                {
                    rq = (antd_client_t*) client->data;
                    if(rq != NULL)
                    {
                        write_msg_to_client(&msg, rq);
                    }  
                }
                else
                {
                    ERROR("Unable to find client %d to write on channel %s", msg.header.client_id, channel->name);
                }
                break;
            default:
                LOG("Message type %d is not supported in client-application communication", msg.header.type);
                break;
        }
    }
}
static void set_sock_fd(bst_node_t* node, void** args, int argc)
{
    (void) argc;
    fd_set* fd_in = (fd_set*) args[0];
    int* max_fd = args[1];
    antd_tunnel_channel_t* channel = (antd_tunnel_channel_t*) node->data;
    if(channel->sock != -1)
    {
        FD_SET(channel->sock, fd_in);
        if(*max_fd < channel->sock)
        {
            *max_fd = channel->sock;
        }
    }
}
static void multiplex(antd_tunnel_t* tunnel_p)
{
    int max_fdm, status;
	fd_set fd_in;
    int status = 0;
    struct timeval timeout;
    int rc;
    size_t i = 0;
    chain_t it;
    antd_tunnel_channel_t* channel;
    void *args[2];
    while(status == 0)
    {
        timeout.tv_sec = 0;
	    timeout.tv_usec = SELECT_TIMEOUT;
        FD_ZERO(&fd_in);
        FD_SET(tunnel_p->hotline, &fd_in);
        max_fdm = tunnel_p->hotline;
        pthread_mutex_lock(&tunnel_p->lock);
        args[0] = (void*) &fd_in;
        args[1] = (void*) &max_fdm;
        bst_for_each(tunnel_p->channels, set_sock_fd, args, 2);
        pthread_mutex_unlock(&tunnel_p->lock);
        rc = select(max_fdm + 1, &fd_in, NULL, NULL, &timeout);
        switch (rc)
	    {
            case -1:
                LOG("Error %d on select()\n", errno);
                status = 1;
                break;
            case 0:
                // time out
                // sleep here
                break;
            // we have data
            default:
                if(FD_ISSET(tunnel_p->hotline, &fd_in))
                {
                    monitor_hotline(tunnel_p->hotline);
                }
                pthread_mutex_lock(&tunnel_p->lock);
                args[0] = (void*) &fd_in;
                bst_for_each(tunnel_p->channels, handle_channel,args, 1);
                pthread_mutex_unlock(&tunnel_p->lock);
        }
    }
}

void init()
{
    char path[MAX_CHANNEL_PATH];
    // initialise the lock
    (void) pthread_mutex_init(&g_tunnel.lock,NULL);
    // initialise the channel
    g_tunnel.hotline = -1;
    g_tunnel.channels = NULL;
    g_tunnel.id_allocator = 0;

    if((g_tunnel.hotline = mk_socket(HOT_LINE_SOCKET, path) == -1))
    {
        ERROR("Unable to create hotline socket");
        destroy();
        return;
    }

    // create the thread
    if (pthread_create(&g_tunnel.tid, NULL,(void *(*)(void *))multiplex, (void*)&g_tunnel) != 0)
    {
        ERROR("pthread_create: cannot create tunnel multiplex thread: %s\n", strerror(errno));
        destroy();
    }
}

static void free_subscribers(bst_node_t* node, void** args, int argc)
{
    (void) argc;
    (void) args;
    antd_tunnel_channel_t* channel = (antd_tunnel_channel_t*) node->data;
    destroy_channel(channel);
}
void destroy()
{
    char path[BUFFLEN];
    pthread_mutex_lock(&g_tunnel.lock);
    if(g_tunnel.tid != -1)
        pthread_join(g_tunnel.tid, NULL);
    
    bst_for_each(g_tunnel.channels, free_subscribers, NULL, 0);
    if(g_tunnel.hotline != -1)
    {
        (void) close(g_tunnel.hotline);
        (void) snprintf(path, BUFFLEN, "%s/%s/%s", __plugin__.tmpdir, SOCK_DIR_NAME, HOT_LINE_SOCKET);
        (void) unlink(path);
    }
    bst_free(g_tunnel.channels);
    pthread_mutex_unlock(&g_tunnel.lock);
    pthread_mutex_destroy(&g_tunnel.lock);
}
static void process_client_message(antd_tunnel_msg_t* msg, antd_client_t* client)
{
    char buff[BUFFLEN+1];
    bst_node_t* node;
    antd_tunnel_channel_t* channel;
    int hash_val;
    // let send it to the correct channel
    switch (msg->header.type)
    {
    case CHANNEL_OK:
    case CHANNEL_ERROR:
    case CHANNEL_DATA:
        node = bst_find(g_tunnel.channels, msg->header.channel_id);
        if(node)
        {
            channel = (antd_tunnel_channel_t*)node->data;
            if(channel)
            {
                if(msg_write(channel->sock, &msg) == -1)
                {
                    ERROR("Unable to write data to channel [%s] from client %d", channel->name, msg->header.client_id);
                }
            }
        }
        break;
    
    case CHANNEL_SUBSCRIBE:
    case CHANNEL_UNSUBSCRIBE:
        if(msg->header.size > MAX_CHANNEL_NAME)
        {
            msg->header.type = CHANNEL_ERROR;
            (void) snprintf(buff, BUFFLEN, "Channel name is too long. Max length is %d", MAX_CHANNEL_NAME);
            msg->header.size = strlen(buff);
            msg->data = buff;
            ERROR("%s", buff);
            write_msg_to_client(msg, client);
            return;
        }
        (void)memcpy(buff, msg->data, msg->header.size);
        buff[msg->header.size] = '\0';
        hash_val = simple_hash(buff);
        node = bst_find(g_tunnel.channels, hash_val);
        if(node)
        {
            channel = (antd_tunnel_channel_t*)node->data;
            if(channel)
            {
                if(msg->header.type == CHANNEL_SUBSCRIBE)
                {
                    g_tunnel.id_allocator++;
                    channel->subscribers = bst_insert(channel->subscribers, g_tunnel.id_allocator, client);
                    // sent ok to client
                    msg->header.type = CHANNEL_OK;
                    msg->header.channel_id = hash_val;
                    msg->header.size = sizeof(g_tunnel.id_allocator);
                    (void)memcpy(buff, &g_tunnel.id_allocator, sizeof(g_tunnel.id_allocator));
                    write_msg_to_client(msg, client);
                }
                else
                {
                    channel->subscribers = bst_delete(channel->subscribers, msg->header.client_id);
                    msg->header.type = CHANNEL_OK;
                    msg->header.channel_id = hash_val;
                    msg->header.size = 0;
                    write_msg_to_client(msg, client);
                }
            }
        }
        else
        {
            msg->header.type = CHANNEL_ERROR;
            (void) snprintf(buff, BUFFLEN, "Channel not found");
            msg->header.size = strlen(buff);
            msg->data = buff;
            ERROR("%s", buff);
            write_msg_to_client(msg, client);
        }
        break;

    default:
        LOG("Unsupported message type for client msg %d", msg->header.type);
        break;
    }
}
void *handle(void *rqdata)
{
    antd_request_t *rq = (antd_request_t *)rqdata;
    antd_task_t *task = antd_create_task(NULL, (void *)rq, NULL, time(NULL));
    ws_msg_header_t *h = NULL;
    antd_tunnel_msg_t msg;
    struct timeval timeout;
    uint8_t* buffer;
    fd_set fd_in;
    int rc, long_value, offset;
    task->priority++;
    int cl_fd = ((antd_client_t *)rq->client)->sock;
    if(g_tunnel.tid == -1)
    {
        ERROR("The tunnel plugin is not initialised correctly");
        return task;
    }
    if (ws_enable(rq->request))
    {
        timeout.tv_sec = 0;
        timeout.tv_usec = 500;
        FD_ZERO(&fd_in);
        FD_SET(cl_fd, &fd_in);
        rc = select(cl_fd + 1, &fd_in, NULL, NULL, &timeout);
        switch (rc)
        {
        case -1:
            LOG("Error on select(): %s\n", strerror(errno));
            ws_close(rq->client, 1011);
            /** TODO: remove all subscriber of this ws connection */
            return task;
        case 0:
            // time out
            break;
        // we have data
        default:
            pthread_mutex_lock(&g_tunnel.lock);
            h = ws_read_header(rq->client);
            pthread_mutex_unlock(&g_tunnel.lock);
            if (h)
            {
                if (h->mask == 0)
                {
                    LOG("Data is not mask");
                    // kill the child process
                    free(h);
                    pthread_mutex_lock(&g_tunnel.lock);
                    ws_close(rq->client, 1011);
                    pthread_mutex_unlock(&g_tunnel.lock);
                    /** TODO: remove all subscriber of this ws connection */
                    return task;
                }
                if (h->opcode == WS_CLOSE)
                {
                    LOG("Websocket: connection closed");
                    pthread_mutex_lock(&g_tunnel.lock);
                    ws_close(rq->client, 1011);
                    pthread_mutex_unlock(&g_tunnel.lock);
                    free(h);
                    /** TODO: remove all subscriber of this ws connection */
                    return task;
                }
                if (h->opcode == WS_BIN)
                {
                    // we have data, now read the message,
                    // the message must be in bin
                    buffer = (uint8_t*) malloc(h->plen + 1);
                    if(buffer)
                    {
                        pthread_mutex_lock(&g_tunnel.lock);
                        rc = ws_read_data(rq->client,h, h->plen, buffer);
                        pthread_mutex_unlock(&g_tunnel.lock);
                        if(h->plen == 0)
                        {
                            offset = 0;
                            // verify begin magic
                            (void)memcpy(&long_value, buffer,sizeof(long_value));
                            offset += sizeof(long_value);
                            if(long_value != MSG_MAGIC_BEGIN)
                            {
                                ERROR("Invalid begin magic number: %d, expected %d", long_value, MSG_MAGIC_BEGIN);
                                free(buffer);
                                goto reschedule_task;
                            }
                            // msgtype
                            (void) memcpy(&msg.header.type, buffer + offset, sizeof(msg.header.type));
                            offset += sizeof(msg.header.type);

                            // channel id
                            (void) memcpy(&msg.header.channel_id, buffer + offset, sizeof(msg.header.channel_id));
                            offset += sizeof(msg.header.channel_id);

                            // client id
                            (void) memcpy(&msg.header.client_id, buffer + offset, sizeof(msg.header.client_id));
                            offset += sizeof(msg.header.client_id);

                            // data size
                            (void) memcpy(&msg.header.size, buffer + offset, sizeof(msg.header.size));
                            offset += sizeof(msg.header.size);

                            // data
                            msg.data = buffer + offset;
                            offset += msg.header.size;

                            // verify end magic
                            (void)memcpy(&long_value, buffer + offset ,sizeof(long_value));
                            offset += sizeof(long_value);
                            if(long_value != MSG_MAGIC_END)
                            {
                                ERROR("Invalid end magic number: %d, expected %d", long_value, MSG_MAGIC_END);
                                free(buffer);
                                goto reschedule_task;
                            }

                            // now we have the message
                            pthread_mutex_lock(&g_tunnel.lock);
                            process_client_message(&msg, rq->client);
                            pthread_mutex_unlock(&g_tunnel.lock);
                        }
                        free(buffer);
                    }
                }
                free(h);
            }
    }
reschedule_task:
    task->handle = handle;
    task->type = HEAVY;
    task->access_time = time(NULL);
    return task;
}