Closes#325
Add a new subid_init() function which can be used to specify the
stream on which error messages should be printed. (If you want to
get fancy you can redirect that to memory :) If subid_init() is
not called, use stderr. If NULL is passed, then /dev/null will
be used.
This patch also fixes up the 'Prog', which previously had to be
defined by any program linking against libsubid. Now, by default
in libsubid it will show (subid). Once subid_init() is called,
it will use the first variable passed to subid_init().
Signed-off-by: Serge Hallyn <serge@hallyn.com>
Some distributions, notably Fedora, have the following order of nsswitch
modules by default:
passwd: sss files
group: sss files
The advantage of serving local users through SSSD is that the nss_sss
module has a fast mmapped-cache that speeds up NSS lookups compared to
accessing the disk an opening the files on each NSS request.
Traditionally, this has been done with the help of nscd, but using nscd
in parallel with sssd is cumbersome, as both SSSD and nscd use their own
independent caching, so using nscd in setups where sssd is also serving
users from some remote domain (LDAP, AD, ...) can result in a bit of
unpredictability.
More details about why Fedora chose to use sss before files can be found
on e.g.:
https://fedoraproject.org//wiki/Changes/SSSDCacheForLocalUsers
or:
https://docs.pagure.org/SSSD.sssd/design_pages/files_provider.html
Now, even though sssd watches the passwd and group files with the help
of inotify, there can still be a small window where someone requests a
user or a group, finds that it doesn't exist, adds the entry and checks
again. Without some support in shadow-utils that would explicitly drop
the sssd caches, the inotify watch can fire a little late, so a
combination of commands like this:
getent passwd user || useradd user; getent passwd user
can result in the second getent passwd not finding the newly added user
as the racy behaviour might still return the cached negative hit from
the first getent passwd.
This patch more or less copies the already existing support that
shadow-utils had for dropping nscd caches, except using the "sss_cache"
tool that sssd ships.
Some of the supplied tools use functions which are not signal-safe.
Most of the times it's exit() vs. _exit().
In other times it's how the standard output or standard error is
handled. FILE-related functions shall be avoided, therefore I replaced
them with write().
Also there is no need to call closelog(). At worst, it allows to
trigger a deadlock by issuing different signal types at bad timings.
But as these fixes are about race conditions, expect bad timings in
general for these bugs to be triggered. :)
passwd, shadow, group, gshadow etc. can be managed via nss -
e.g. system default accounts can be specified using nss_altfiles,
rather than in /etc/. Thus despite having default accounts, these
files can be missing on disk and thus should be opened with O_CREATE
whenever they are attempted to be opened in O_RDWR modes.
* Changelog: Update documentation of 2013-07-28 mancha entry.
* lib/prototypes.h, lib/encrypt.c: Update splint marker,
pw_encrypt can return NULL.
* lib/encrypt.c: Fix outdated statement on GNU crypt.
* src/chgpasswd.c: Improve diagnostic to user when pw_encrypt
fails and use fail_exit() instead of exit().
* src/chpasswd.c: Likewise.
* src/newusers.c: Likewise.
* src/passwd.c: Likewise when new password is encrypted.
* src/newgrp.c: Improve diagnostic to user and syslog when
pw_encrypt fails. Do not apply 1s penalty as this is not an
invalid password issue.
* src/passwd.c: Likewise when password is checked.
a salt that violates specs. On Linux, crypt() also fails with
DES/MD5 salts in FIPS140 mode. Rather than exit() on NULL returns
we send them back to the caller for appropriate handling.
annotations.
* src/pwconv.c, src/pwunconv.c, src/grpconv.c, src/grpunconv.c:
Ignore return value of spw_rewind, pw_rewind, sgr_rewind, and
gr_rewind.
* lib/commonio.h: Both head and tail cannot be owned. Set tail as
dependent.
* src/expiry.c: Ignore return value of expire ().
* src/expiry.c: The catch_signals function does not use its sig
parameter.
* src/userdel.c: Last audit_logger parameter is a
shadow_audit_result, use SHADOW_AUDIT_FAILURE instead of 0.
src/chpasswd.c, src/groupmems.c, src/usermod.c, src/chgpasswd.c,
src/vipw.c, src/su.c, src/useradd.c, src/groupmod.c, src/passwd.c,
src/groupadd.c, src/chage.c, src/faillog.c, src/chsh.c: Use
booleans for tests.
* src/userdel.c, src/gpasswd.c, src/groupmems.c, src/usermod.c,
src/groupmod.c, src/passwd.c: Use a break even after usage().
src/newusers.c, src/chpasswd.c, src/groupmems.c, src/usermod.c,
src/chgpasswd.c, src/vipw.c, src/su.c, src/useradd.c,
src/groupmod.c, src/passwd.c, src/groupadd.c, src/chage.c,
src/faillog.c, src/chsh.c: If someone uses the -h/--help options,
the usage should not go to stderr nor should the utility exit with
non-zero status. All of the shadow utils do just this
unfortunately, so convert them over to sanity.
* man/groupmems.8.xml, man/gpasswd.1.xml: Added option -h/--help.
when the changes are committed to the system. Do not log failure
for on-memory changes to audit or syslog. Make sure failures and
inconsistencies will be reported in case of unexpected failures
(e.g. malloc failures). Only specify an audit message if it is not
implicitly implied by the type argument. Removed fail_exit
(replaced by atexit(do_cleanups)). Log failures in case of
permission denied.
src/newusers.c, src/pwconv.c, src/chpasswd.c, src/logoutd.c,
src/chfn.c, src/groupmems.c, src/usermod.c, src/pwunconv.c,
src/expiry.c, src/groupdel.c, src/chgpasswd.c, src/useradd.c,
src/su.c, src/groupmod.c, src/passwd.c, src/pwck.c,
src/groupadd.c, src/chage.c, src/login.c, src/grpconv.c,
src/groups.c, src/grpunconv.c, src/chsh.c: Prog is now global (not
static to the file) so that it can be used by the helper functions
of libmisc.
* lib/prototypes.h: Added extern char *Prog.
* libmisc/find_new_gid.c, libmisc/find_new_uid.c: Indicate the
program name with the warning.
* src/chage.c, src/chfn.c, src/chgpasswd.c, src/chpasswd.c,
src/chsh.c, src/gpasswd.c, src/groupadd.c, src/groupmems.c,
src/groupmod.c, src/grpck.c, src/grpconv.c, src/grpunconv.c,
src/passwd.c, src/pwck.c, src/pwconv.c, src/pwunconv.c,
src/useradd.c, src/userdel.c, src/usermod.c: Harmonize the error
message sent to stderr in case of *_update () failure.
* src/chage.c, src/chsh.c, src/groupadd.c, src/passwd.c: Do not
log to syslog when pw_update() or spw_update() fail.
* src/newusers.c: Do not log specific error message to stderr when
sgr_update() fails.
* src/pwconv.c: Remove duplicated definition of Prog.
src/newgrp.c, src/passwd.c, src/su.c: Use the same stderr and
syslog warnings when the username cannot be determined.
* src/newgrp.c: Reuse the same stderr message for groups which do
not exist in the system.
* src/grpconv.c, src/grpunconv.c, src/pwconv.c, src/pwunconv.c,
src/vipw.c: Open syslog with the right identification name.
* src/vipw.c: Log unlock errors to syslog.
* src/vipw.c: Log edits to syslog.
* src/chage.c, src/chfn.c, src/chsh.c, src/gpasswd.c,
src/groupadd.c, src/groupdel.c, src/groupmod.c, src/grpconv.c,
src/grpunconv.c, src/passwd.c, src/pwck.c, src/pwunconv.c,
src/useradd.c, src/usermod.c: Harmonize the syslog levels. Failure
to close or unlock are errors. Failure to open files are warnings.
support for long options --add (-a), --delete (-d),
--remove-password (-r), --restrict (-R), --administrators (-A),
and --members (-M)
* man/gpasswd.1.xml: Document the new long options.
* src/gpasswd.c: The sgrp structure is only used if SHADOWGRP is
defined.
src/groupadd.c, src/groupdel.c, src/groupmems.c, src/groupmod.c,
src/grpconv.c, src/grpunconv.c, src/newusers.c, src/pwconv.c,
src/pwunconv.c, src/useradd.c, src/userdel.c: Harmonize the name
of the variables keeping the lock status, to match the shadow
library prefixes.
src/gpasswd.c, src/groupadd.c, src/groupdel.c, src/groupmems.c,
src/groupmod.c, src/grpck.c, src/grpconv.c, src/grpunconv.c,
src/newusers.c, src/passwd.c, src/pwck.c, src/pwconv.c,
src/pwunconv.c, src/useradd.c, src/userdel.c, src/usermod.c: In
case of a lock failure, indicate to the user that she can try
again later. Do not log to syslog.
lib/sgroupio.c, lib/sgroupio.h, lib/shadowio.c, lib/shadowio.h:
Added *_dbname() functions to retrieve the name of the databases.
* lib/groupio.c, lib/groupio.h, lib/pwio.c, lib/pwio.h,
lib/sgroupio.c, lib/sgroupio.h, lib/shadowio.c, lib/shadowio.h:
*_name() functions renamed *setname().
* src/grpck.c, src/pwck.c: Likewise.
* lib/groupio.h, lib/pwio.h, lib/sgroupio.h, lib/shadowio.h: Added
the name of the arguments to the prototypes.
* src/chage, src/chfn.c, src/chgpasswd.c, src/chpasswd.c,
src/chsh.c, src/gpasswd.c, src/groupadd.c, src/groupdel.c,
src/groupmod.c, src/grpck.c, src/grpconv.c, src/grpunconv.c,
src/newusers.c, src/passwd.c, src/pwck.c, src/pwconv.c,
src/pwunconv.c, src/useradd.c, src/userdel.c, src/usermod.c:
Harmonize the erro & syslog messages in case of failure of the
*_lock(), *_open(), *_close(), *_unlock(), *_remove() functions.
* src/chgpasswd.c, src/chpasswd.c, src/usermod.c: Avoid
capitalized messages.
* src/chpasswd.c, src/useradd.c, src/usermod.c: Harmonize messages
in case of inexistent entries.
* src/usermod.c: Harmonize messages in case of already existing
entries.
* src/newusers.c, src/useradd.c: Simplify PAM error handling.
* src/useradd.c: Report failures to unlock files (stderr, syslog,
and audit). But do not fail (continue).
* src/useradd.c (open_files): Do not report to syslog & audit
failures to lock or open the databases. This might be harmless,
and the logs were not already informed that a change was
requested.
* src/usermod.c: It's not the account which is unlocked, but its
password.
int.
* src/gpasswd.c: Ignore the return value of signal(). The signal
handlers are only changed for the last steps of gpasswd, and there
is no need to restore them.
* src/gpasswd.c: Avoid implicit conversion of pointers / integers
/ chars to booleans.
* src/gpasswd.c: Ignore the return value of putchar() and fflush()
before exiting.
* src/gpasswd.c: check_list() renamed is_valid_user_list(), and
return a bool.
* src/gpasswd.c: Ignore return value of setlocale(),
bindtextdomain(), and textdomain().
Files with no license use the default 3-clauses BSD license. The copyright
were mostly not recorded; they were updated according to the Changelog.
"Julianne Frances Haugh and contributors" changed to "copyright holders
and contributors".
to Christian Henz (http://bugs.debian.org/467488)
* src/gpasswd.c (get_group): Do not fail if gshadow is not present. Just use
the group file and set the grent structure
* src/gpasswd.c (check_perms): The permissions should be checked
using both the gshadow and group file. Add a <struct group *>
parameter, and check if the gshadow file exists (is_shadowgrp).
* src/gpasswd.c (main): Do not use sgent.sg_mem or sgent.sg_adm if
the gshadow file is not present (sgent is not initialized in that
case). The fields of sgent can be set, but not used.
