functions are implimented as wrappers around getservent(), which means it's
up to getservent() to do all the work. The NIS support in getservent()
only allows it to scan through the services.byname map one entry at a
time until it finds the requested service name/port. This can be painfully
slow due to the overhead involved (lots and lots of successive RPCs).
To fix this, we allow getservbyname() and getservbyport() to signal
getservent() that if NIS is turned on (there's a '+' in /etc/services),
the usual yp_first()/yp_next() linear search should be abandoned and
yp_match() used instead. This causes getservent() to immediately
locate the requested entry instead of wasting time groping through the
whole map.
The downside is that this trick is accomplished by exporting a couple of
pointers from getservent.c which getservbyname.c and getservbyport.c can
preset in order to tell getservent() what to do. If all three functions
were in the same source module, then the extra cruft could be delcared
static to avoid poluting the global symbol space. Maybe they should be
combined anyway. For now I've settled on prepending lots of underscores.
privileged port within a single bind(), rather than looping through
attempts to bind over and over again over progressively lower ports.
This should speed up rlogin/rsh etc, and will probably cure some of the
strange rlogin hangs that have been reported in the past where rresvport()
managed to bind() to a port address that it shouldn't have.
man pages up to mdoc guidelines and fix some minor formatting glitches.
Also fixed a number of man pages to not abuse the .Xr macro to
display functions and path names and a lot of other junk.
broken. The translation from network number to ASCII string was not
working correctly (you would sometimes get things like 0.244.0.0 instead
of 244.0.0).
Also copied results of yp_match() to a static buffer for consistency
with gethostbynis.c.
Note: _getnetbynisaddr() chops off trailing .0's, i.e. 244.0.0 is
truncated to 244. By contrast, getnetbyht.c code (for local /etc/networks
lookups) leaves the traling .0's in place. This means that the NIS
and local file lookups will match different things when looking up the
same network number. I'm not sure which is the correct behavior. (I
think the DNS lookup code tries all combinations -- should the NIS
and local host lookup routines do that too?)
- Fix problem described in PR #1079: _gethostbynisaddr() doesn't
work. Make it accept the same arguments as all the other
gethostby*addr() functions and properly convert the supplied IP
address into a text string so that yp_match() can find it in the
hosts.byaddr map.
- Also fix potential memory leak: copy the results of yp_match() to
a static buffer and free the result (yp_match() returns dynamically
allocated memory).
ether_addr.c:
- Since I was in the neighborhood, fix ether_ntohost() and
ether_hostton() so that they don't bogusly for a free(result)
when yp_match() fails.
in the main text of various man pages.
Thanks to Warner Losh for adding an option to manck to allow
it to scan the entire man page looking for bogus xrefs, instead
of just checking the SEE ALSO section.
Also corrected a few minor formatting errors, file location and cross
references in some of the section 3 man pages.
This shuts up a lot of the output from "manck" for section 3.
both call getservent() to do most of the work, so we only need to modify
this file to take care of everybody).
Note that there is only one NIS services map (services.byname) even
though there are getservbyname() and getservbyport() library functions.
Since Bruce changed the #include <res_config.h> to #include "res_config.h"
this is no longer needed, and only makes the 'make' more verbose for
no real reason.
Note that this was done by selective patching from diffs, to not conflict
with the 4.4bsd base code.. This was *not* a trivial task.. I have been
testing this code (apart from cosmetic changes) in my libc for a while now.
Obtained from: Paul Vixie <paul@vix.com>
Fix for PR #510. The original problem was that __ivaliduser() was
failing to grant access to a machine listed in a +@netgroup specified
in /etc/hosts.equiv, even though the host being checked was most
certainly in the +@netgroup.
The /etc/hosts.equiv file in question looked like this:
localhost
+@netgroup
The reason for the failure was had to do with gethostbyaddr(). Inside
the __ivaliduser() routine, we need to do a gethostbyaddr() in order
to get back the actual name of the host we're trying to validate since
we're only passed its IP address. The hostname returned by gethostbyaddr()
is later passed as an argument to innetgr(). The problem is that
__icheckhost() later does a gethostbyname() of its own, which clobbers
the buffer returned by gethostbyaddr().
The fix is just to copy the hostname into a private buffer and use
_that_ as the 'host' argument that gets passed to innetgr().
And here I was crawling all over the innetgr() code thinking the
problem was there. *sigh*
- getnetgrent.c: address some NIS compatibility problems. We really need
to use the netgroup.byuser and netgroup.byhost maps to speed up innetgr()
when using NIS. Also, change the NIS interaction in the following way:
If /etc/netgroup does not exist or is empty (or contains only the
NIS '+' token), we now use NIS exclusively. This lets us use the
'reverse netgroup' maps and is more or less the behavior of other
platforms.
If /etc/netgroup exists and contains local netgroup data (but no '+').
we use only lthe local stuff and ignore NIS.
If /etc/netgroup exists and contains both local data and the '+',
we use the local data nd the netgroup map as a single combined
database (which, unfortunately, can be slow when the netgroup
database is large). This is what we have been doing up until now.
Head off a potential NULL pointer dereference in the old innetgr()
matching code.
Also fix the way the NIS netgroup map is incorporated into things:
adding the '+' is supposed to make it seem as though the netgroup
database is 'inserted' wherever the '+' is placed. We didn't quite
do it that way before.
(The NetBSD people apparently use a real, honest-to-gosh, netgroup.db
database that works just like the password database. This is
actually a neat idea since netgroups is the sort of thing that
can really benefit from having multi-key search capability,
particularly since reverse lookups require more than a trivial
amount of processing. Should we do something like this too?)
- netgroup.5: document all this stuff.
- rcmd.c: some sleuthing with some test programs linked with my own
version of innetgr() has revealed that SunOS always passes the NIS
domain name to innetgr() in the 'domain' argument. We might as well
do the same (if YP is defined).
- ether_addr.c: also fix the NIS interaction so that placing the
'+' token in the /etc/ethers file makes it seem like the NIS
ethers data is 'inserted' at that point. (Chances are nobody will
notice the effect of this change, which is just te way I like it. :)
the comment before checking for long lines, so there was a possibility
that the wrap-around might be used as an exploitable hostname.
Reviewed by:
Submitted by:
Obtained from:
Change strtok() to strsep(), cause memory corruption for all
programs which use strtok() too in the same time.
Fix potential NULL reference, depends of /etc/hosts.conf format
Fix the bug when service name fetched always from beginning of the line,
not from parsed token.
programs which use strtok() too in the same time.
Fix potential NULL reference, depends of /etc/hosts.conf format
Fix the bug when service name fetched always from beginning of the line,
not from parsed token.
that everyone else does: you can now use +host/-host, +user,-user and
+@netgroup/-@netgroup in /etc/hosts.equiv, /.rhosts, /etc/hosts.lpd and
~/.rhosts. Previously, __ivaliduser would only do host/user matches,
which was lame. This affects all the r-commands, lpd, and any other
program/service that uses ruserok().
An example of the usefullness of this feature would be a hosts.equiv
file that looks like this:
+@equiv-hosts
Since the netgroup database can now be accessed via NIS, this lets you
set up client machines once and then never have to worry about them
again: all hosts.equiv changes can now be done through NIS. Once I
finish with getpwent.c, we'll be able to do similar wacky things
with login authentication too. (Our password field substitution
will finally be on par with everyone else's, and I'll finally be
able to fully integrate my FreeBSD machine into my network without
having to worry about the grad students sneaking into it when I'm
not looking. :)
Danger Will Robinson! I tested this thing every which way I could, but
Murphy's Law applies! If anybody spots a potential security problem with
the way my matching algorithm works, tell me immediately! I don't want
crackers snickering and calling me names behind my back. :)
incredibly obnoxious, but also makes inverse mappings work when the local
resolver is in a cache-only configuration. (Maybe this is actually
a bug in BIND?)
While trying to figure out why rlogind wasn't working right for root,
I noticed that man wouldn't come back with a man page for iruserok, but
it would for ruserok. Checking the lib/net directory's Makefile.inc
file shows that the link to the rcmd man page just isn't getting
created.
>How-To-Repeat:
Do a 'man iruserok' and notihing will come back, where a 'man ruserok'
will.
Submitted by: Brian Moore <ziff@houdini.eecs.umich.edu>
Obtained from: NetBSD-bugs mailing list
getnet* configuration. (It's highly unlikely that you'd want to do
something different, and network lookups aren't common enough to justify
their own configuration file.)
