Re: [9fans] standalone authserver on CF card

[erik quanstrom <quanstro@coraid.com>]

this really helps us.  i know that steve has a list of bad
ftp users to reject out-of-hand, but this exponential backoff
keeps the bad guys from bothering our auth server enough to
notice.  we still get quite a few connections, though

- erik


/n/sources/plan9//sys/src/cmd/ip/ftpd.c:519,524 - ftpd.c:519,528
  int
  usercmd(char *name)
  {
+ 	static int usercmds = 1000;
+
+ 	if(usercmds <<= 1 > 2000)
+ 		sleep(usercmds);
  	logit("user %s %s", name, nci->rsys);
  	if(loggedin)
  		return reply("530 Already logged in as %s", user);
/n/sources/plan9//sys/src/cmd/ip/ftpd.c:537,542 - ftpd.c:541,548
  		strcpy(user, "none");
  	else if(anon_everybody)
  		strcpy(user,"none");
+ 	if(strcmp(user, "Administrator") == 0)
+ 		return reply("530 no way jose");
  	if(strcmp(user, "*none") == 0){
  		if(!anon_ok)
  			return reply("530 Not logged in: anonymous disallowed");
/n/sources/plan9//sys/src/cmd/ip/ftpd.c:593,600 - ftpd.c:599,606
  		ch->nresp = strlen(response);
  		ai = auth_response(ch);
  		if(ai == nil) {
- 			static long delay = 100;
-
+ 			static long delay = 1000;
+ hoser:
  			sleep(delay);		/* deter password-guessers */
  			if (delay < 60*1000)
  				delay *= 2;
/n/sources/plan9//sys/src/cmd/ip/ftpd.c:601,607 - ftpd.c:607,613
  			return reply("530 Not logged in: %r");
  		}
  		if(auth_chuid(ai, nil) < 0)
- 			return reply("530 Not logged in: %r");
+ 			goto hoser;
  		auth_freechal(ch);
  		ch = nil;