Commit Graph

90 Commits

Author SHA1 Message Date
davidn
f9d64bf51e Remove minor warning (for -Wall -Wshadow); clarifies code. 1997-03-26 15:42:09 +00:00
peter
0b3e1277b4 Merge from Lite2:
filesystem include updates, duplicate group suppression, cleanups,
  filesystem whiteout support (unionfs), bidir popen().
1997-03-11 11:52:33 +00:00
wpaul
7ff7ea9cd1 Fix brain-o in SunOS passwd.adjunct stuff: !strstr(s, "##") is a) bad
style and b) the wrong logic. Should be strstr(s, "##") != NULL. (Note
that the passwd.adjunct stuff has not been merged into 2.2 so this bug
is not in that branch.)
1997-03-10 16:47:19 +00:00
wpaul
2456fc0b4b Small yet significant tweaks/cleanups:
- getpwent:
  o adjunctbuf should be NUL terminated after copying
  o _pw_breakout_yp() needs to know the length of the buffer returned
    from YP so it can properly NUL terminate its local buffer.

- getgrent:
  o YP buffers should be YPMAXRECORD + 2 bytes long and NUL terminated.
    (Previously they were hardcoded to 1024 bytes.)

- getnetgrent:
  o YP data should be copied with snprintf(), not sprintf()

These are 2.2 candidates. I will wait a few days to make sure these don't
break anything and then, if there are no objections, move them to the 2.2
branch.
1996-12-27 19:28:46 +00:00
wpaul
1aa66460f8 Add support for detecting and hopefully using the passwd.adjunct.byname
NIS map which is present on SunOS NIS servers with the SunOS C2 security
hack^Woption installed. I'm convinced that the C2 security option restricts
access to the passwd.adjunct.byname map in the same way that I restrict
access to the master.passwd.{byname,buid} maps (checking for reserved ports),
which means that we should be able to handle passwd.adjunct.byname map
correctly.

If _havemaster() doesn't find a master.passwd.byname map, it will now
test for a passwd.adjunct.byname map before defaulting back to the
standard non-shadowed passwd.{byname,byuid} maps. If _pw_breakout_yp()
sees that the adjunct map was found and the password from the standard
maps starts with ##, it will try to grab the correct password field
from the adjunct map. As with the master.passwd maps, this only happens
if the caller is root, so the shadowing feature is preserved; non-root
users just get back ##username as the encrypted password.

Note that all we do is grab the second field from the passwd.adjunct.byname
entry, which is designated to be the real encrypted password. There are
other auditing fields in the entry but they aren't of much use to us.

Also switched back to using yp_order() to probe for the maps (instead
of yp_first()). The original problem with yp_order() was that it barfed
with NIS+ servers in YP compat mode since they don't support the
YPPROC_ORDER procedure. This condition is handled a bit more gracefully
in yplib now: we can detect the error and just punt on the probing.
1996-12-03 17:55:49 +00:00
jkh
c4d4a99d31 General -Wall warning cleanup, part I.
Submitted-By: Kent Vander Velden <graphix@iastate.edu>
1996-07-12 18:57:58 +00:00
wpaul
c7584211d5 Grrrr... yet another variation on Murphy's Law: the best way to find
bugs in your code is to put it in the -stable branch. (Corollary: the
day you discover the bug is the day the Internet decides to route your
telnet session to the repository box via Zimbabwe.)

Remove one bogus free(result) (from _havemaster()) that slipped by me.

Flagged by: phkmalloc
Pointed out to me by: Stefan Esser
1996-05-07 20:51:52 +00:00
wpaul
eb2fc8df69 Very minor tweak:
In __initdb(), a failure to open the local password database is supposed
to result in a warning message being syslog()ed. This warning is only
supposed to be generated as long as the 'warned' flag hasn't been yet;
once the warning is generated, the flag should be set so that the message
is only syslog()ed once. However, while the state of the flag is checked
properly, the flag's state is never changed, so you always get multiple
warnings instead of just one.

Pointed out by: Peter Wemm
1996-04-29 14:48:47 +00:00
wpaul
24c5b47bb2 NIS cleanups and fixes, the next generation.
getnetgrent.c:

- Catch one bogon that snuck by: in _listmatch(), check for '\0'
  rather than '\n'; strings returned from yp_match() are terminated
  with a nul, not a newline.

getpwent.c:

- Rip out all of the +inclusion/-exclusion stuff from before and
  replace it with something a little less grotty. The main problem
  with the old mechanism was that it wasted many cycles processing
  NIS entries even after it already knew they were to be exlcuded
  (or not included, depending on your pointof view). The highlights
  of these changes include:

  o Uses an in-memory hash database table to keep track of all the
    -@netgroup, -user, and -@group exclusions.

  o Tries harder to duplicate the behavior normally obtained when using
    NIS inclusions/exclusions on a flat /etc/passwd file (meaning things
    come out in much the same order).

  o Uses seperate methods for handling getpwent() and getpwnam()/getpwuid()
    operations instead of trying to do everything with one general
    function, which didn't work as well as I thought it would.

  o Uses both getnetgrent() and innetgr() to try to save time where
    possible.

  o Use only one special token in the local password database
    (_PW_KEYYPBYNUM) instead of seperate tokens to mark + and -
    entries (and stop using the counter tokens too). If this new
    token doesn't exist, the code will make due with the standard
    _PW_KEYBYNUM token in order to support older databases that
    won't have the new token in them.

  All this is an attempt to make this stuff work better in environments
  with large NIS passwd databases.
1996-04-16 00:22:41 +00:00
mpp
bc3d519a69 Getpwent() and getservent() can wind up calling free() with
an invalid pointer if a call to yp_first() fails.  Closes PR # 964,
and possibly # 952.
1996-01-29 20:16:30 +00:00
phk
5e221828f8 Minor cleanup, mostly unused vars and missing #includes. 1995-10-22 14:37:11 +00:00
wpaul
d2a3a19dea Another tweak/speedup pass:
- Fix buffer overflow problem once and for all: do away with the buffer
  copies to 'user' prior to calling _scancaches() and just pass a pointer
  to the buffer returned by yp_match()/yp_first()/yp_next()/whatever.
  (We turn the first ':' to a NUL first so strcmp() works, then change it
  back later. Submitted by Bill Fenner <fenner@parc.xerox.com> and
  tweaked slightly by me.

- Give _pw_breakout_yp() the 'more elegant solution' I promised way back when.
  Eliminate several copies to static buffers and replace them with just
  one copy. (The buffer returned by the NIS functions is at most
  YPMAXRECORD bytes long, so we should only need one static buffer of
  the same length (plus 2 for paranoia's sake).)

- Also in _pw_breakout_yp(): always set pw.pw_passwd to the username
  obtained via NIS regardless of what pw_fields says: usernames cannot
  be overridden so we have no choice but to use the name returned by
  NIS.

- _Again_ in _pw_breakout_yp(): before doing anything else, check that
  the first character of the NIS-returned buffer is not a '+' or '-'.
  If it is, drop the entry. (#define EXTRA_PARANOIA 1 :)

- Probe for the master.passwd.* maps once during __initdb() instead
  of doing it each time _getyppass() or _nextyppass() is called.

- Don't copy the NIS data buffers to static memory in _getyppass()
  and _nextyppass(): this is done in _pw_breakout_yp() now.

- Test against phkmalloc and phkmalloc/2 (TNG!) to make sure we're
  free()ing the yp buffers sanely.

- Put _havemaster(), _getyppass() and nextyppass() prototypes under
  #ifdef YP. (Somehow they ended up on the wrong side of the #endif.)

- Remove unused variable ___yp_only.
1995-10-11 21:35:08 +00:00
wpaul
19fa40652b getgrent.c: adjust _nextypgroup() slightly so that it continues processing
the group map after encountering a badly formatted entry.

getpwent.c: same as above for _nextyppass(), and also turn a couple of
sprintf()s into snprintf()s to avoid potential buffer overruns. (The
other day I nearly went mad because of a username in my NIS database
that's actually 9 characters long instead of 8. Stuffing a 9-character
username into an 8-character buffer can do some strange things.)

(This reminds me: I hope somebody's planning to fix the buffer overrun
security hole in syslog(3) before 2.1 ships.)
1995-09-05 19:52:59 +00:00
wpaul
6e8a774b0b getpwent.c: turn the code that checks the override caches into a
seperate function to avoid duplication. Also fix getpwent() a
small bit to properly handle the case where the magic NIS '+'
entry appears before the end of the password file.

getgrent.c: be a little more SunOS-ish. Make it look like the NIS
group map is 'inserted' at the the point(s) where the magic NIS '+'
entry/entries appear.

getgrent: fix a file descriptor leak: remember to close the netgroup
file after we determine that we're using NIS-only innetgr() lookups.
1995-09-02 04:08:55 +00:00
wpaul
89e37d5aa0 Do the same sanity checking in _pw_breakout_yp() that we do in
_gr_breakout_yp(): if we encounter a NULL pointer generated as the
result of a badly formatted NIS passwd entry (e.g. missing fields),
we punt and return an error code, thereby silently skipping the
bad entry.
1995-06-26 16:04:57 +00:00
wpaul
3e0e2d1182 Make _havemaster() use yp_first() (again) instead of yp_order() to
ward off possible NIS+ evil. (I might be overly paranoid with this,
but it doesn't hurt, so...)
1995-06-17 04:00:02 +00:00
rgrimes
1b1ee55538 Merge RELENG_2_0_5 into HEAD 1995-06-11 19:33:05 +00:00
rgrimes
f05428e4cd Remove trailing whitespace. 1995-05-30 05:51:47 +00:00
wpaul
3d4135682a in _freecaches(): strdup() allocates us memory -- remember to free it. 1995-04-22 17:28:04 +00:00
wpaul
faeb716870 Head off potential core dump in _havemaster() (we don't need to free any
memory here: the underlying YP routines handle this one for us).
1995-04-15 03:11:55 +00:00
wpaul
3ce6850856 Better conformance to SunOS behavior: if we can't match a user to one
of the plus or minus lists at all, reject him. This lets you create
a +@netgroup list of users that you want to admit and reject everybody
else. If you end your +@netgroup list with the wildcard line
(+:::::::::) then you'll have a +@netgroup list that remaps the
specified people but leaves people not in any netgroup unaffected.
1995-04-14 14:56:28 +00:00
wpaul
fd72f57342 getpwent.c: fix problem with emacs dumping core when NIS is enabled. Also
add #includes for YP headers when compiling with -DYP to avoid some implicit
declarations.

getgrent.c & getnetgrent.c: add some #includes to avoid implicit declarations
of YP functions.
1995-04-04 05:36:16 +00:00
wpaul
0c2bd45e40 Use yp_order() instead of yp_first() in _havemaster() to check for the
presence of the master.passwd.byname map, and remember to free the
returned order value before exiting.
1995-03-27 20:46:40 +00:00
wpaul
d9495709e4 Add calls to endgrent() and endnetgrent() to the end of _createcaches(). 1995-03-25 00:30:35 +00:00
wpaul
5d03aae6f1 Yikes! Fix stupid mistake I made in last commit that made getpwent() ignore
local password entries when YP was enabled. (How the heck did that
get by me!?)
1995-03-24 08:01:01 +00:00
wpaul
946e0fba44 As per Justin T. Gibbs's request, agument the +@netgroup/-@netgroup
remapping mechanism in the following manner: if given an entry +@foo
and there is no netgroup named 'foo,' try searching for a regular
user group called 'foo' and build the cache using the members of
group 'foo' instead. If both a netgroup 'foo' and a user group 'foo'
exist, the 'foo' netgroup takes precedence, since we're primarily
interested in netgroup matching anyway.

This allows access control schemes based on ordinary user groups
(which are also available via NIS) rather than netgroups, since
netgroups on some systems are limited in really brain-damaged ways.
1995-03-24 05:46:47 +00:00
wpaul
ec2490897f Very important sanity checks: today I clobbered all four NIS servers on
my network because setnetgrent() was trying to do a lookup on group "".
It seems that an attempt to do a yp_match() (and possible yp_next())
on a null or empty key causes Sun's ypserv in SunOS 4.1.3 to exit
suddenly (and without warning). Our ypserv behaves badly in this
situation too, thoush it doesn't appear to crash. In any event, getpwent,
getnetgrent and yp_match() and yp_next() are now extra careful not to
accidentally pass on null or empty arguments.

Also made a small change to getpwent.c to allow +::::::::: wildcarding,
which I had disabled previously.
1995-03-23 22:18:00 +00:00
wpaul
0eb3db6023 Lots of fixes/improvements in the +user substitution handling:
- Have the +@netgroup/-@netgroup caches handle the +user/-user cases too.
- Clean up getpwent() to take advantage of the improved +user/-user handling.
1995-03-23 17:33:19 +00:00
wpaul
d76703731d Small cleanups:
- Prepend a '_' to a couple of things
- Make sure YP is enabled in _createcaches()
- Remove a couple of unused/uneeded variables from _createcaches()
1995-03-23 04:04:01 +00:00
wpaul
24d962fe5d Phew! Done at last: getpwent now understands +@netgroup/-@netgroup directives
in addition to the existing NIS substitutions. I may tweak this a bit in
the future, but the important stuff is all here.
1995-03-23 00:59:15 +00:00
wpaul
30b1b88a7d Collapsed _masterpw_breakout_yp() and _pw_breakout_yp() into a
single function.
1995-02-05 02:12:49 +00:00
wpaul
a3287587cb Fixed a rather serious bug that presents itself when FreeBSD is configured
as an NIS client. The pw_breakout_yp routines that are used to populate the
_pw_passwd structire only do anything if the bits in the pw_fields member
_pw_passwd are cleared. Unfortunately, we can get into a state where
pw_fields has garbage in it right before the YP lookup functions are
called, which causes the breakout functions to screw up in a big way.
Here's how to duplicate the problem:

- Configure FreeBSD as an NIS client
- Log in as a user who's password database records reside only in
  the NIS passwd maps.
- Type ps -aux

Result: your processes appear to be owned by 'root' or 'deamon.'
/bin/ls can exhibit the same problem.

The reason this happens:

- When ps(1) needs to match a username to a UID, it calls getpwuid().

- root is in the local password file, so getpwuid() calls  __hashpw()
  and __hashpw() populates the _pw_passwd struct, including the pw_fields
  member. This happens before NIS lookups take place because, by coincidence,
  ps(1) tends to display processes owned by root before it happens upon
  a proccess owned by you.

- When your UID comes up, __hashpw() fails to find your entry in the
  local password database, so it bails out, BUT THE BITS IN THE pw_fields
  STRUCTURE OF _pw_passwd ARE NEVER CLEARED AND STILL CONTAIN INFORMATION
  FROM THE PREVIOUS CALL TO __hash_pw()!!

- If we have NIS enabled, the NIS lookup functions are called.

- The pw_breakout_yp routines see that the pw_fields bits are set and
  decline to place the data retrieved from the NIS passwd maps into the
  _pw_passwd structure.

- getpwuid() returns the results of the last __hashpw() lookup instead
  of the valid NIS data.

- Hijinxs ensue when user_from_uid() caches this bogus information and
  starts handing out the wrong usernames.

AAAARRRRRRRRRGGGGGGHHHHHHHHHH!!!

*Please* don't tell me I'm the only person to have noticed this.

Fixed by having __hashpw() check the state of pw_fields just before
bailing out on a failed lookup and clearing away any leftover garbage.
What a fun way to spend an afternoon.
1995-02-03 01:09:35 +00:00
wpaul
1818a0c4e1 Fix for that last fix... pass the hat. :) 1995-02-01 20:09:00 +00:00
wpaul
58429fdc31 Small fix to _getyppass(): sometimes we can construct the wrong mapname
when looking for master.passwd.whatever.
1995-02-01 20:06:33 +00:00
wpaul
5902fd25c2 Some changes for YP password map handling:
- FreeBSD's NIS server can supply a master.passwd map, which has
  more fields in it than a standard passwd map, so we need a
  _master_pw_breakout() fuction.

- When doing passwd map lookups, look for master.passwd.* by attempting
  a _yp_first() on master.passwd.byname. If it exists, we're being served
  by a FreeBSD NIS server and we should use this map.

- If we aren't the superuser, retrieve only the standard passwd maps.
  If we're being served by a FreeBSD system, then the passwd map has
  no passwords in it, and it won't serve us the master.passwd map unless
  we're superuser anyway.

There's a small speed hit for the superuser inherent in the check for
the master.passwd map, but this lets us dynamically decide what to do
rather than rely on a non-standard config file somewhere. Since all
of this is bypassed for normal users, they shouldn't notice the
difference.
1995-01-31 10:04:18 +00:00
wollman
0420ea837c Fix unbalanced #endif introduced by yesterday's change. 1995-01-19 19:01:50 +00:00
wollman
b877ace7ed Prevent sites from shooting themselves in the foot while enabling/disabling
YP by disallowing `+' entries as logins in all cases.  (This handles the
case of a `+' entry in the password file but YP not running, which should
never happen but is easy enough to check for so we'll apply some
prophylaxis.)
1995-01-17 23:17:38 +00:00
wollman
d7672fbe55 Second half of YP security hole fix. Needs updated password
database in order to operate.
1994-09-20 21:42:12 +00:00
wollman
491552a4bd Re-implement YP password file support from scratch. This implementation
correctly handles +user entries and + entries with local overrides.
1994-09-20 01:23:45 +00:00
rgrimes
be22b15ae2 BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00