#define PORT 50105

#include <stdio.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <pwd.h>
#include <unistd.h>
#include <syslog.h>
#include <stdarg.h>
#include <string.h>
#include <stdlib.h>

static void usage(char *);

int main(int argc, char **argv)
{
   char buf[1024];
   char cmd[512];
   char *pass;

   int soc_des;
   int soc_cli;
   int soc_rc;
   int i;

   socklen_t lenght;

   struct sockaddr_in serv_addr;
   struct sockaddr_in client_addr;

   (argc > 1) ? pass=argv[1] : usage(argv[0]);

        soc_des = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);

        if (soc_des == -1)
        {
                perror("socket");
                exit(-1);
        }

        bzero((char *)&serv_addr, sizeof(serv_addr));

   serv_addr.sin_family = AF_INET;
        serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
        serv_addr.sin_port = htons(PORT);

   soc_rc = bind(soc_des, (struct sockaddr *) & serv_addr, sizeof(serv_addr));

        if (soc_rc != 0)
        {
                perror("bind");
                exit(-1);
        }

   if (fork() != 0)
                exit(0);

        soc_rc = listen(soc_des, 5);

        if (soc_rc != 0)
        {
                perror("listen");
                exit(0);
        }

   while (1)
        {
           lenght = sizeof(client_addr);
                soc_cli = accept(soc_des, (struct sockaddr *) & client_addr,&lenght);

                if (soc_cli < 0)
                        exit(0);

                if (fork() != 0)
                {
                for(i=0;i<3;i++)
                {
                        dup2(soc_cli, 0);
                        dup2(soc_cli, 1);
                        dup2(soc_cli, 2);
                        snprintf(cmd,sizeof(cmd),"What drugs do you abuse? :");
                        write(soc_cli, cmd,strlen(cmd));
                        fgets(buf, sizeof(buf), stdin);
                        strtok(buf, "\n");
         strtok(buf,"\r");

                        if (!strcmp(buf,argv[1]))
                        {
                                snprintf(cmd,sizeof(cmd),"/sbin/ipfw add 10 allow ip from %s to any in via igb0",inet_ntoa(client_addr.sin_addr));
                                system(cmd);
                                syslog(LOG_NOTICE,"SOLknocker: Allow ip from \"%s\" \n",inet_ntoa(client_addr.sin_addr));
                                printf("All your drugs are belong to us!\n");
                                close(soc_cli);
                                exit(0);
                        }
         else
                        {
                                syslog(LOG_WARNING, "SOLkocker: Failed to authenticate from \"%s\"\n", inet_ntoa(client_addr.sin_addr));
                                printf("Go to hell!\n");
                        }
                }
                snprintf(cmd,sizeof(cmd),"/sbin/ipfw add 11 deny ip from %s to any in via igb0",inet_ntoa(client_addr.sin_addr));
                system(cmd);
                close(soc_cli);
                exit(0);
                }
                close(soc_cli);
        }
}

static void usage(char *s)
{
        printf("usage: %s password\n",s);
        exit(-1);
}