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Sending packets in a queue using NFQUEUE?

I use libnetfilter_queueand iptableswith the goal of NFQUEUEstoring incoming packets in three different queues using --queue-num x.

I successfully create three queues with functions libnetfilter_queue, bind them, listen to them and read from them as follows:

/* given 'h' as a handler of one of my three queues */
fd = nfq_fd(h);
while ((rv = recv(fd, buf, sizeof(buf), 0)) && rv >= 0) {
    nfq_handle_packet(h, buf, rv);
}

The callback function initiated with the help nfq_handle_packethas a command nfq_set_verdict(qh, id, NF_ACCEPT, 0, NULL);where it sends the packet as soon as it is processed. The problem is that I do not want every packet to be sent immediately, since I need to store them in a user structure (see below).

So, I came across a potential solution: I can name the NF_DROPverdict instead NF_ACCEPTfor every packet that I want to queue (so that it will not be sent immediately), save it in my custom structure, and then (sooner or later) re-enter it according to my need.

It sounds great, but the situation is this: I don’t know how to reinsert my queue packages from my pleasure for my user space application. Is it correct to use nfq_set_verdictagain at the same point in my code, but with NF_ACCEPTverdict? Or should I open a socket (possibly raw)?

This is my custom structure.

struct List {
    int queue;
    int pktsize;
    unsigned char *buffer;
    struct nfq_q_handle *qh;
    struct nfqnl_msg_packet_hdr *hdr;
    struct List *next;
};

representing a package caught with the rule above.

These are my lines where to store packages.

struct List *List0 = NULL;  // low priority
struct List *List1 = NULL;  // medium priority
struct List *List2 = NULL;  // high priority

I have one Ubuntu 14.04 3.13.0-57-generic.

Any suggestions would be appreciated.

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