oss-sec mailing list archives
Re: Re: Some fun with tcp_wrappers
From: wietse () porcupine org (Wietse Venema)
Date: Thu, 16 Apr 2009 07:59:20 -0400 (EDT)
Tomas Hoger:
The good_client (tcp_wrappers wrapping function in portmap / nfs-utils / ...) problem is rather interesting too, as it creates problems due to its attempt to avoid unneeded DNS lookups (workaround for hosts_ctl limitation?) and support host aliases (tcp_wrappers limitation).
See my previous email. Programs such as portmappers must not look
up hostname information, since that would result in an infinite
recursion when host lookups use SUNRPC services. To state the
obvious: the portmapper would directly or indirectly send SUNRPC
calls to itself, in order to locate the NIS server.
Before discussing changes to a program, it is a good investment of
time to find out how the program works, and why it works in the
specific way it works.
Wietse
Current thread:
- Some fun with tcp_wrappers Tomas Hoger (Apr 15)
- Re: Some fun with tcp_wrappers Wietse Venema (Apr 15)
- Re: Re: Some fun with tcp_wrappers Tomas Hoger (Apr 15)
- Re: Re: Some fun with tcp_wrappers Wietse Venema (Apr 15)
- Re: Re: Some fun with tcp_wrappers Tomas Hoger (Apr 15)
- Re: Re: Some fun with tcp_wrappers Wietse Venema (Apr 15)
- Re: Re: Some fun with tcp_wrappers Wietse Venema (Apr 15)
- Re: Re: Some fun with tcp_wrappers Steven M. Christey (Apr 15)
- Re: Re: Some fun with tcp_wrappers Tomas Hoger (Apr 16)
- Re: Re: Some fun with tcp_wrappers Wietse Venema (Apr 16)
- Re: Re: Some fun with tcp_wrappers Tomas Hoger (Apr 16)
- Re: Re: Some fun with tcp_wrappers Wietse Venema (Apr 16)
- Re: Re: Some fun with tcp_wrappers Steven M. Christey (Apr 24)
- Re: Re: Some fun with tcp_wrappers Tomas Hoger (Apr 28)
- Re: Re: Some fun with tcp_wrappers Tomas Hoger (Apr 15)
- Re: Some fun with tcp_wrappers Wietse Venema (Apr 15)
- Re: Re: Some fun with tcp_wrappers Tomas Hoger (Apr 16)
- Re: Re: Some fun with tcp_wrappers Wietse Venema (Apr 16)
