Commit Graph

465 Commits

Author SHA1 Message Date
Alejandro Colomar
170b76cdd1 Disable utmpx permanently
On Linux, utmpx and utmp are identical.  However, documentation (manual
pages) covers utmp, and just says about utmpx that it's identical to
utmp.  It seems that it's preferred to use utmp, at least by reading the
manual pages.

Moreover, we were defaulting to utmp (utmpx had to be explicitly enabled
at configuration time).  So, it seems safer to just make it permanent,
which should not affect default builds.

Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-22 10:31:43 +01:00
Alejandro Colomar
54847a76da Remove preprocessor conditionals that are always true
In a previous commit, we made USE_TERMIOS unconditionally defined.
Let's just remove it, and remove the condition everywhere.

Reported-by: Iker Pedrosa <ipedrosa@redhat.com>
Cc: Christian Göttsche <cgzones@googlemail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-15 16:22:05 -06:00
Alejandro Colomar
0e0c55aeca Assume F_* and SEEK_* macros are defined
They are required by POSIX.1-2001.

Link: <https://github.com/shadow-maint/shadow/pull/600>
Cc: Christian Göttsche <cgzones@googlemail.com>
Cc: Iker Pedrosa <ipedrosa@redhat.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-15 16:22:05 -06:00
Alejandro Colomar
9dfa71f71c Remove code conditional on S_SPLINT_S
I don't know for sure what that is, but it's redefining setlocale(3)
and LC_ALL, which is are defined by C99, so it's supect of being some
variety of an extinct dynosaur.  Maybe related to the Dodo.

Link: <https://github.com/shadow-maint/shadow/pull/600>
Cc: Christian Göttsche <cgzones@googlemail.com>
Cc: Iker Pedrosa <ipedrosa@redhat.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-15 16:22:05 -06:00
Alejandro Colomar
143e346dd5 Assume strdup(3) exists
It is required by POSIX.1-2001.

Link: <https://github.com/shadow-maint/shadow/pull/600>
Cc: Christian Göttsche <cgzones@googlemail.com>
Cc: Iker Pedrosa <ipedrosa@redhat.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-15 16:22:05 -06:00
Alejandro Colomar
a082a3975f Assume fsync(2) exists
It is required by POSIX.1-2001.

Cc: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-15 16:22:05 -06:00
Alejandro Colomar
e71c23586a Assume fchown(2) exists
It is required by POSIX.1-2001.

Cc: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-15 16:22:05 -06:00
Alejandro Colomar
9c86e07067 Assume fchmod(2) exists
It is required by POSIX.1-2001.

Cc: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-15 16:22:05 -06:00
Alejandro Colomar
5777e583cd Assume <termios.h> exists
It is required by POSIX.1-2001.

Cc: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-15 16:22:05 -06:00
Alejandro Colomar
b47aa1e9aa Assume <utmpx.h> exists
It is required by POSIX.1-2001.

Cc: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-15 16:22:05 -06:00
Alejandro Colomar
578f286215 Assume <unistd.h> exists
It is required by POSIX.1-2001.

Cc: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-15 16:22:05 -06:00
Alejandro Colomar
9d8c3df93c Assume NULL exists
ISO C99 requires NULL.

Link: <https://github.com/shadow-maint/shadow/pull/600>
Cc: Christian Göttsche <cgzones@googlemail.com>
Cc: Iker Pedrosa <ipedrosa@redhat.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-12 09:16:43 +01:00
Alejandro Colomar
3a32f5278d Assume strerror(3) exists
ISO C99 requires strerror(3).

Link: <https://github.com/shadow-maint/shadow/pull/600>
Cc: Christian Göttsche <cgzones@googlemail.com>
Cc: Iker Pedrosa <ipedrosa@redhat.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-12 09:16:43 +01:00
Alejandro Colomar
5e8df2b2b5 Assume fputs(3) exists
ISO C99 requires fputs(3).

Link: <https://github.com/shadow-maint/shadow/pull/600>
Cc: Christian Göttsche <cgzones@googlemail.com>
Cc: Iker Pedrosa <ipedrosa@redhat.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-12 09:16:43 +01:00
Alejandro Colomar
c26b682381 Assume <locale.h> exists
ISO C99 requires <locale.h>.

Other files in the project already include <locale.h> unconditionally,
so it's reasonable to assume that it is always available.

Link: <https://github.com/shadow-maint/shadow/pull/600>
Cc: Christian Göttsche <cgzones@googlemail.com>
Cc: Iker Pedrosa <ipedrosa@redhat.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-12 09:16:43 +01:00
Alejandro Colomar
1eaa30756e Assume <errno.h> exists
ISO C99 requires <errno.h>.

Many files in the project already include <errno.h> unconditionally,
so it's reasonable to assume that it is always available.

Link: <https://github.com/shadow-maint/shadow/pull/600>
Cc: Christian Göttsche <cgzones@googlemail.com>
Cc: Iker Pedrosa <ipedrosa@redhat.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-12 09:16:43 +01:00
Alejandro Colomar
c4d9dcacc9 Assume <stdbool.h> exists
ISO C99 requires <stdbool.h>.

Many files in the project already include <stdbool.h> unconditionally,
so it's reasonable to assume that it is always available.

Link: <https://github.com/shadow-maint/shadow/pull/600>
Cc: Christian Göttsche <cgzones@googlemail.com>
Cc: Iker Pedrosa <ipedrosa@redhat.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-12 09:16:43 +01:00
Alejandro Colomar
ab91ec10b4 Hide [[gnu::malloc(deallocator)]] in a macro
Clang doesn't implement this attribute and reports an error.  Work
around it by hiding it in a macro that will be empty in clang.

Reported-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-05 10:47:19 +01:00
Alex Colomar
155c9421b9 libmisc: agetpass(), erase_pass(): Add functions for getting passwords safely
There are several issues with getpass(3).

Many implementations of it share the same issues that the infamous
gets(3).  In glibc it's not so terrible, since it's a wrapper
around getline(3).  But it still has an important bug:

If the password is long enough, getline(3) will realloc(3) memory,
and prefixes of the password will be laying around in some
deallocated memory.

See the getpass(3) manual page for more details, and especially
the commit that marked it as deprecated, which links to a long
discussion in the linux-man@ mailing list.

So, readpassphrase(3bsd) is preferrable, which is provided by
libbsd on GNU systems.  However, using readpassphrase(3) directly
is a bit verbose, so we can write our own wrapper with a simpler
interface similar to that of getpass(3).

One of the benefits of writing our own interface around
readpassphrase(3) is that we can hide there any checks that should
be done always and which would be error-prone to repeat every
time.  For example, check that there was no truncation in the
password.

Also, use malloc(3) to get the buffer, instead of using a global
buffer.  We're not using a multithreaded program (and it wouldn't
make sense to do so), but it's nice to know that the visibility of
our passwords is as limited as possible.

erase_pass() is a clean-up function that handles all clean-up
correctly, including zeroing the entire buffer, and then
free(3)ing the memory.  By using [[gnu::malloc(erase_pass)]], we
make sure that we don't leak the buffers in any case, since the
compiler will be able to enforce clean up.

Link: <https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/commit?id=7ca189099d73bde954eed2d7fc21732bcc8ddc6b>
Reported-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-05 10:47:19 +01:00
Serge Hallyn
90424e7c20 Don't warn when failed to open /etc/nsswitch.conf
Maybe we should have a debug mode where it's still printed, but
we don't, so let's be quieter.

Closes #557
2022-11-08 10:18:17 -06:00
Iker Pedrosa
16afe18142 Raise limit for passwd and shadow entry length
Moreover, include checks to prevent writing entries longer than the
length limit.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1422497

Signed-off-by: Tomáš Mráz <tm@t8m.info>
Signed-off-by: Iker Pedrosa <ipedrosa@redhat.com>
2022-10-14 10:41:40 +02:00
Alejandro Colomar
3dc1754e50 Use libc MAX() and MIN()
glibc, musl, FreeBSD, and OpenBSD define the MAX() and MIN()
macros in <sys/param.h> with the same definition that we use.
Let's not redefine it here and use the system one, as it's
effectively the same as we define (modulo whitespace).

See:

shadow (previously):

alx@asus5775:~/src/shadow/shadow$ grepc -ktm MAX
./lib/defines.h:318:#define MAX(x,y) (((x) > (y)) ? (x) : (y))

glibc:

alx@asus5775:~/src/gnu/glibc$ grepc -ktm -x 'sys/param.h$' MAX
./misc/sys/param.h:103:#define MAX(a,b) (((a)>(b))?(a):(b))

musl:

alx@asus5775:~/src/musl/musl$ grepc -ktm -x 'sys/param.h$' MAX
./include/sys/param.h:19:#define MAX(a,b) (((a)>(b))?(a):(b))

OpenBSD:

alx@asus5775:~/src/bsd/openbsd/src$ grepc -ktm -x 'sys/param.h$' MAX
./sys/sys/param.h:193:#define	MAX(a,b) (((a)>(b))?(a):(b))

FreeBSD:

alx@asus5775:~/src/bsd/freebsd/freebsd-src$ grepc -ktm -x 'sys/param.h$' MAX
./sys/sys/param.h:333:#define	MAX(a,b) (((a)>(b))?(a):(b))

Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-09-30 16:13:36 -05:00
Alex Colomar
0d9799de04 Don't test for NULL before calling free(3)
free(3) accepts NULL, since the oldest ISO C.  I guess the
paranoid code was taking care of prehistoric implementations of
free(3).  I've never known of an implementation that doesn't
conform to this, so let's simplify this.

Remove xfree(3), which was effectively an equivalent of free(3).

Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-09-29 16:03:53 +02:00
Christian Göttsche
e74bfe2c75 lib: use strzero where applicable
Replace `memzero (s, strlen(s))` with just the internal wrapper
`strzero (s)` where the underlying allocated size is not known.
2022-09-27 16:52:06 +02:00
Luca BRUNO
14e7caf6b2 lib/commonio: make lock failures more detailed
This tweaks the database locking logic so that failures in the
link-checking paths are more detailed.
The rationale for this is that I've experienced a non-deterministic
bug which seems to be coming from this logic, and I'd like to get
more details about the actual failing condition.
2022-09-15 10:31:13 -05:00
genBTC
23634d8de7 useradd: check MLS enablement before setting serange Resolves: https://github.com/shadow-maint/shadow/issues/552 2022-09-02 20:29:34 -05:00
Christian Göttsche
dab764d019 Require symlink support
Require lstat(2), lchown(2), S_IFLNK and S_ISLNK from POSIX.1-2001.

Already unconditionally used in lib/tcbfuncs.c and lib/run_part.c.
2022-08-17 12:34:01 -05:00
Christian Göttsche
c6c8130db4 Use function format attribute where applicable
Allow the compiler to verify the format string against the supplied
arguments.

    chage.c:239:51: warning: format not a string literal, format string not checked [-Wformat-nonliteral]
      239 |                 (void) strftime (buf, sizeof buf, format, tp);
          |                                                   ^~~~~~
2022-08-06 11:27:56 -05:00
Christian Göttsche
ce185b2b48 Drop obsolete prototype for log_dolog()
log_dolog() is neither implemented nor used.
2022-08-06 11:27:56 -05:00
Christian Göttsche
87d5a54ba0 Drop superfluous const from return type
salt.c:102:22: warning: type qualifiers ignored on function return type [-Wignored-qualifiers]
      102 | static /*@observer@*/const unsigned long SHA_get_salt_rounds (/*@null@*/int *prefered_rounds);
          |                      ^~~~~
    salt.c:110:22: warning: type qualifiers ignored on function return type [-Wignored-qualifiers]
      110 | static /*@observer@*/const unsigned long YESCRYPT_get_salt_cost (/*@null@*/int *prefered_cost);
          |                      ^~~~~

    subordinateio.c:160:8: warning: type qualifiers ignored on function return type [-Wignored-qualifiers]
      160 | static const bool range_exists(struct commonio_db *db, const char *owner)
          |        ^~~~~
2022-08-06 11:27:56 -05:00
Christian Göttsche
44917600b6 Drop register keyword
Compilers are free to ignore the indented hint and modern optimizations
should create good code by themself.

(As such it is for example deprecated in C++17.)
2022-08-06 11:27:56 -05:00
Christian Göttsche
c5090d91a1 Return void pointer from xmalloc
xmalloc is a wrapper around malloc(3), which bails out on OOM failures.
As such it returns raw memory and is used to allocated all kind of
types.
2022-08-06 11:27:56 -05:00
Christian Göttsche
e32b4a9a81 Declare read-only parameters const
Signal callers arguments are not going to be modified and allow passing
const pointers.
2022-08-06 11:27:56 -05:00
Iker Pedrosa
3ec32f9975 subordinateio: also compare the owner ID
IDs already populate /etc/subuid and /etc/subgid files so it's necessary
not only to check for the owner name but also for the owner ID of a
given range.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2093311

Signed-off-by: Iker Pedrosa <ipedrosa@redhat.com>
2022-07-20 09:29:31 -05:00
Iker Pedrosa
3b89b71680 Initialize local variables
CWE-457 by CodeQL.

Signed-off-by: Iker Pedrosa <ipedrosa@redhat.com>
2022-05-24 07:49:11 -05:00
Iker Pedrosa
0c7ded471f Add header guards
Signed-off-by: Iker Pedrosa <ipedrosa@redhat.com>
2022-05-24 07:49:11 -05:00
Iker Pedrosa
0b51cde162 Remove commented out code and FIXMEs
In order to remove some of the FIXMEs it was necessary to change the
code and call getulong() instead of getlong().

Signed-off-by: Iker Pedrosa <ipedrosa@redhat.com>
2022-05-24 07:49:11 -05:00
Iker Pedrosa
e101219ad7 nss: get shadow_logfd with log_get_logfd()
If /etc/nsswitch.conf doesn't exist podman crashes because shadow_logfd
is NULL. In order to avoid that load the log file descriptor with the
log_get_logfd() helper function.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2038811

Signed-off-by: Iker Pedrosa <ipedrosa@redhat.com>
2022-01-15 08:47:50 -06:00
Alejandro Colomar
1b96f6a9b3 Remove AC_HEADER_TIME and TIME_WITH_SYS_TIME checks
Systems on which <sys/time.h> conflicted with <time.h> are obsolete.

This macro has been marked as obsolete by autoconf documentation.

Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
2022-01-15 08:25:53 -06:00
Alejandro Colomar
5538ecd7cc Remove AC_HEADER_STAT and STAT_MACROS_BROKEN
As autoconf documentation says, this macro is obsolescent, as no
current systems have the bug in S_ISDIR, S_ISREG, etc..
The affected systems were Tektronix UTekV, Amdahl UTS, and
Motorola System V/88.

Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
2022-01-15 08:25:53 -06:00
Alejandro Colomar
9e788adf56 Remove AC_HEADER_SYS_WAIT
GNU autoconf documentation marks this macro as obsolescent, as
current systems are compatible with POSIX.

Simplify code to unconditionally include <sys/wait.h>, and don't
redefine WIFEXITSTATUS() and WIFEXITED(), since they are mandated
by POSIX.

Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
2022-01-15 08:25:53 -06:00
Alejandro Colomar
5450f9a904 Remove old compatibility DIRECT macro.
Use struct dirent directly.  See parent commit.

Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
2022-01-15 08:25:53 -06:00
Alejandro Colomar
79e28694ef Remove AC_HEADER_DIRENT
POSIX.1-2001 defines 'struct dirent' in <dirent.h>.  It replaces
the old 'struct direct' found in BSDs.  All of the systems that I
checked (including FreeBSD, NetBSD, and OpenBSD), now provide
<dirent.h> with 'struct dirent', as mandated by POSIX.

Since autoconf first checks <dirent.h> and only if it's missing it
checks other header files, it's clear that it will always find
<dirent.h>, so let's simplify.

GNU autoconf documentation declares this macro as obsolescent, and
acknowledges that all current systems with directory libraries
have <dirent.h>:
<https://www.gnu.org/software/autoconf/manual/autoconf-2.70/html_node/Particular-Headers.html>

Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
2022-01-15 08:25:53 -06:00
Serge Hallyn
39eea79d8d
Merge pull request #487 from cgzones/misc_warnings
Resolve several compiler warnings
2022-01-03 09:45:12 -06:00
Serge Hallyn
98f943f2a5
Merge pull request #481 from alejandro-colomar/STDC_HEADERS
Assume C89 is available
2022-01-03 09:37:06 -06:00
Christian Göttsche
7a799ebb2c Ensure memory cleaning
Compilers are allowed to and do optimize memset(3) calls away for
pointers not accessed in the future. Since the memzero wrappers purpose
is exactly to unconditionally override memory (e.g. for stored
passwords) do not implement via regular memset(3), but via either
memset_s(3), explicit_bzero(3) or a hand written implementation using
volatile pointers.

See https://wiki.sei.cmu.edu/confluence/display/c/MSC06-C.+Beware+of+compiler+optimizations
2022-01-03 15:09:39 +01:00
Christian Göttsche
b2bc1f6927 Do not return garbage in run_parts
If scandir(3) returns 0, the uninitialized value of execute_result will
be returned.
2022-01-03 15:09:17 +01:00
Christian Göttsche
a8166a86ed Declare read-only arguments of run_part(s) const
run_part() and run_parts() do not modify their directory, name and
action arguments.
Also include the header in the implementation to provide the prototypes.

useradd.c:2495:59: warning: cast discards ‘const’ qualifier from pointer target type [-Wcast-qual]
 2495 |         if (run_parts ("/etc/shadow-maint/useradd-pre.d", (char*)user_name,
      |                                                           ^
useradd.c:2495:24: warning: passing argument 1 of ‘run_parts’ discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
 2495 |         if (run_parts ("/etc/shadow-maint/useradd-pre.d", (char*)user_name,
      |                        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from useradd.c:45:
../lib/run_part.h:2:22: note: expected ‘char *’ but argument is of type ‘const char *’
    2 | int run_parts (char *directory, char *name, char *action);
      |                ~~~~~~^~~~~~~~~
useradd.c:2496:25: warning: passing argument 3 of ‘run_parts’ discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
 2496 |                         "useradd")) {
      |                         ^~~~~~~~~
2022-01-03 15:09:17 +01:00
Christian Göttsche
119cee142e Declare argument of nss_init const
nss_init() does not modify its path argument, thus declare it const.
Also drop superfluous prototype.

nss.c:54:31: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
   54 |                 nsswitch_path = NSSWITCH;
      |                               ^
2022-01-03 15:09:17 +01:00
Christian Göttsche
45bba0e190 Use strict prototypes
Function declarations with no argument declare functions taking an
arbitrary number of arguments. Use the special type void to declare
functions taking no argument.
2022-01-03 15:09:17 +01:00