Commit Graph
48 Commits
Author SHA1 Message Date
Christian Göttsche c99d8d0a08 Avoid comparisons of different signs
Comparisons if different signedness can result in unexpected results.
Add casts to ensure operants are of the same type.

    gettime.c: In function 'gettime':
    gettime.c:58:26: warning: comparison of integer expressions of different signedness: 'long long unsigned int' and 'time_t' {aka 'long int'} [-Wsign-compare]
       58 |         } else if (epoch > fallback) {
          |                          ^

Cast to time_t, since epoch is less than ULONG_MAX at this point.

    idmapping.c: In function 'write_mapping':
    idmapping.c:202:48: warning: comparison of integer expressions of different signedness: 'int' and 'long unsigned int' [-Wsign-compare]
      202 |                 if ((written <= 0) || (written >= (bufsize - (pos - buf)))) {
          |                                                ^~

    newgidmap.c: In function ‘main’:
    newgidmap.c:178:40: warning: comparison of integer expressions of different signedness: ‘int’ and ‘long unsigned int’ [-Wsign-compare]
      178 |         if ((written <= 0) || (written >= sizeof(proc_dir_name))) {
          |                                        ^~
    newuidmap.c: In function ‘main’:
    newuidmap.c:107:40: warning: comparison of integer expressions of different signedness: ‘int’ and ‘long unsigned int’ [-Wsign-compare]
      107 |         if ((written <= 0) || (written >= sizeof(proc_dir_name))) {
          |                                        ^~
2023-01-25 12:31:17 +01:00
Christian Göttsche 43508ac476 Drop redundant declaration
environ is exported in <unistd.h>.

    env.c:29:15: warning: redundant redeclaration of 'environ' [-Wredundant-decls]
       29 | extern char **environ;
          |               ^~~~~~~
    login.c:92:15: warning: redundant redeclaration of ‘environ’ [-Wredundant-decls]
       92 | extern char **environ;
          |               ^~~~~~~
    sulogin.c:40:15: warning: redundant redeclaration of ‘environ’ [-Wredundant-decls]
       40 | extern char **environ;
          |               ^~~~~~~
    newgrp.c:32:15: warning: redundant redeclaration of ‘environ’ [-Wredundant-decls]
       32 | extern char **environ;
          |               ^~~~~~~
2023-01-25 12:31:17 +01:00
Christian Göttsche 46d3058341 copydir: fix impl usage
copydir.c: In function 'copy_dir':
    copydir.c:517:32: warning: passing argument 1 of 'copy_tree' from incompatible pointer type [-Wincompatible-pointer-types]
      517 |             return (copy_tree (src, dst, false, reset_selinux,
          |                                ^~~
          |                                |
          |                                const struct path_info *
    In file included from copydir.c:20:
    ../lib/prototypes.h:108:35: note: expected 'const char *' but argument is of type 'const struct path_info *'
      108 | extern int copy_tree (const char *src_root, const char *dst_root,
          |                       ~~~~~~~~~~~~^~~~~~~~
    copydir.c:517:37: warning: passing argument 2 of 'copy_tree' from incompatible pointer type [-Wincompatible-pointer-types]
      517 |             return (copy_tree (src, dst, false, reset_selinux,
          |                                     ^~~
          |                                     |
          |                                     const struct path_info *
    ../lib/prototypes.h:108:57: note: expected 'const char *' but argument is of type 'const struct path_info *'
      108 | extern int copy_tree (const char *src_root, const char *dst_root,
          |                                             ~~~~~~~~~~~~^~~~~~~~

Fixes: 74c17c71 ("Add support for skeleton files from /usr/etc/skel")
2023-01-25 12:31:17 +01:00
Christian Göttsche e0d79ee032 Modernize manual memzero implementation
Instead of using volatile pointers to prevent the compiler from
optimizing the call away, use a memory barrier.
This requires support for embedded assembly, which should be fine after
the recent requirement bumps.
2023-01-25 11:07:25 +01:00
Christian Göttsche 90ead3cfb8 Replace flawed memset_s usage
memset_s() has a different signature than memset(3) or explicit_bzero(),
thus the current code would not compile.  Also memset_s()
implementations are quite rare.
Use the C23 standardized version memset_explicit(3).

Fixes: 7a799ebb ("Ensure memory cleaning")
2023-01-25 11:07:25 +01:00
Christian Göttsche 1d936c968a Warn if failed to read existing /etc/nsswitch.conf
Commit 90424e7c ("Don't warn when failed to open /etc/nsswitch.conf")
removed the logging for failing to read /etc/nsswitch.conf to reduce the
noise in the case the file does not exists (e.g. musl based systems).

Reintroduce a warning if /etc/nsswitch.conf exists but we failed to read
it (e.g. permission denied).

Improves: 90424e7c ("Don't warn when failed to open /etc/nsswitch.conf")
2023-01-04 14:21:43 -06:00
Christian Göttsche 8e53db927a lib: use memzero where applicable
Use memzero when operating in a buffer of known size to clear all bytes
and avoid leaking the size of the stored data.
2022-09-27 16:52:06 +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
Christian Göttsche faeab50e71 Avoid races in copy_tree()
Use *at() functions to pin the directory operating in to avoid being
redirected by unprivileged users replacing parts of paths by symlinks to
privileged files.

Introduce a path_info struct with the full path and dirfd and name
information for *at() functions, since the full path is needed for link
resolution, SELinux label lookup and ACL attributes.
2022-08-17 12:34:01 -05:00
Christian Göttsche 6cbec2d0aa Address minor compiler warnings
copydir.c:666:44: warning: unsigned conversion from 'int' to '__mode_t' {aka 'unsigned int'} changes value from '-4096' to '4294963200' [-Wsign-conversion]
      666 |         if (   (mknod (dst, statp->st_mode & ~07777, statp->st_rdev) != 0)
          |                                            ^

    copydir.c:116:1: warning: missing initializer for field 'quote' of 'struct error_context' [-Wmissing-field-initializers]
      116 | };
          | ^
    In file included from copydir.c:27:
    /usr/include/attr/error_context.h:30:23: note: 'quote' declared here
       30 |         const char *(*quote) (struct error_context *, const char *);
          |                       ^~~~~
2022-08-17 12:34:01 -05:00
Christian Göttsche f606314f0c More robust file content copy in copy_tree()
Bail out on read(2) failure, continue on EINTR, support short writes and
increase chunk size.
2022-08-17 12:34:01 -05:00
Christian Göttsche 1d281273b1 Fail if regular file pre-exists in copy_tree()
Similar to the default behavior of mkdir(2), symlink(2), link(2) and
mknod(2).
2022-08-17 12:34:01 -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 f6f8bcd2a5 Avoid races in remove_tree()
Use *at() functions to pin the directory operating in to avoid being
redirected by unprivileged users replacing parts of paths by symlinks to
privileged files.
2022-08-17 12:34:01 -05:00
Christian Göttsche e9ae247cb1 Avoid races in chown_tree()
Use *at() functions to pin the directory operating in to avoid being
redirected by unprivileged users replacing parts of paths by symlinks to
privileged files.
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 477c8e6f42 Drop unused function subid_init() 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 8f093ea93a Add include for uid_t
Allow IDEs to parse the header file on its own.
2022-08-06 11:27:56 -05:00
Christian Göttsche 4c641c1f2a Drop unnecessary prototype
The function is defined directly after.
2022-08-06 11:27:56 -05:00
Christian Göttsche ae38d3a87f Declare read-only data const 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
Christian Göttsche 0fe4128ee6 po: update translations
Add language identifiers and fix line break.
2022-08-06 11:27:56 -05:00
Christian Göttsche af76c25f77 configure.ac: bump gettext version
Version 1.19.1 was released in June 2014.

    configure.ac:697: warning: AM_PROG_MKDIR_P: this macro is deprecated, and will soon be removed.
    configure.ac:697: You should use the Autoconf-provided 'AC_PROG_MKDIR_P' macro instead,
    configure.ac:697: and use '$(MKDIR_P)' instead of '$(mkdir_p)'in your Makefile.am files.
    ./lib/autoconf/general.m4:2434: AC_DIAGNOSE is expanded from...
    aclocal.m4:780: AM_PROG_MKDIR_P is expanded from...
    m4/po.m4:23: AM_PO_SUBDIRS is expanded from...
    m4/gettext.m4:57: AM_GNU_GETTEXT is expanded from...
    configure.ac:697: the top level
    configure.ac:697: warning: The macro `AC_TRY_LINK' is obsolete.
    configure.ac:697: You should run autoupdate.
    ./lib/autoconf/general.m4:2920: AC_TRY_LINK is expanded from...
    lib/m4sugar/m4sh.m4:692: _AS_IF_ELSE is expanded from...
    lib/m4sugar/m4sh.m4:699: AS_IF is expanded from...
    ./lib/autoconf/general.m4:2249: AC_CACHE_VAL is expanded from...
    ./lib/autoconf/general.m4:2270: AC_CACHE_CHECK is expanded from...
    m4/gettext.m4:365: gt_INTL_MACOSX is expanded from...
    m4/gettext.m4:57: AM_GNU_GETTEXT is expanded from...
    configure.ac:697: the top level
    configure.ac:697: warning: The macro `AC_TRY_LINK' is obsolete.
    configure.ac:697: You should run autoupdate.
    ./lib/autoconf/general.m4:2920: AC_TRY_LINK is expanded from...
    lib/m4sugar/m4sh.m4:692: _AS_IF_ELSE is expanded from...
    lib/m4sugar/m4sh.m4:699: AS_IF is expanded from...
    ./lib/autoconf/general.m4:2249: AC_CACHE_VAL is expanded from...
    ./lib/autoconf/general.m4:2270: AC_CACHE_CHECK is expanded from...
    m4/gettext.m4:57: AM_GNU_GETTEXT is expanded from...
    configure.ac:697: the top level
    configure.ac:697: warning: The macro `AC_TRY_LINK' is obsolete.
    configure.ac:697: You should run autoupdate.
    ./lib/autoconf/general.m4:2920: AC_TRY_LINK is expanded from...
    lib/m4sugar/m4sh.m4:692: _AS_IF_ELSE is expanded from...
    lib/m4sugar/m4sh.m4:699: AS_IF is expanded from...
    ./lib/autoconf/general.m4:2249: AC_CACHE_VAL is expanded from...
    ./lib/autoconf/general.m4:2270: AC_CACHE_CHECK is expanded from...
    m4/iconv.m4:20: AM_ICONV_LINK is expanded from...
    m4/gettext.m4:57: AM_GNU_GETTEXT is expanded from...
    configure.ac:697: the top level
2022-08-06 11:27:56 -05:00
Christian Göttsche caad9b987c configure.ac: replace deprecated aliases
See https://www.gnu.org/software/libtool/manual/html_node/LT_005fINIT.html

    configure.ac:25: warning: The macro `AM_ENABLE_STATIC' is obsolete.
    configure.ac:25: You should run autoupdate.
    m4/ltoptions.m4:259: AM_ENABLE_STATIC is expanded from...
    configure.ac:25: the top level
    configure.ac:26: warning: The macro `AM_ENABLE_SHARED' is obsolete.
    configure.ac:26: You should run autoupdate.
    m4/ltoptions.m4:205: AM_ENABLE_SHARED is expanded from...
    configure.ac:26: the top level
2022-08-06 11:27:56 -05:00
Christian Göttsche 48ceff86de configure: replace obsolete autoconf macros
Replace
 AC_HELP_STRING by AS_HELP_STRING,
 AC_GNU_SOURCE by AC_USE_SYSTEM_EXTENSIONS,
 AC_TRY_COMPILE by AC_COMPILE_IFELSE and
 AM_PROG_LIBTOOL by LT_INIT.

See https://www.gnu.org/software/autoconf/manual/autoconf-2.69/html_node/Obsolete-Macros.html
2022-05-10 09:55:18 +02:00
Christian Göttsche 58b6e97a9e passwd: erase password copy on all error branches 2022-04-30 13:19:14 -05:00
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 debea9b761 Avoid unused variable warnings when building with PAM
newusers.c:467:15: warning: unused variable ‘cp’ [-Wunused-variable]
  467 |         char *cp;
      |               ^~

newusers.c:611:13: warning: unused variable ‘bad_s’ [-Wunused-variable]
  611 |         int bad_s;
      |             ^~~~~
2022-01-03 15:09:17 +01:00
Christian Göttsche 7909308285 Declare read-only lookup pointers const
pwck.c:587:31: warning: cast discards ‘const’ qualifier from pointer target type [-Wcast-qual]
  587 |                         spw = (struct spwd *) spw_locate (pwd->pw_name);
      |                               ^

grpck.c:599:31: warning: cast discards ‘const’ qualifier from pointer target type [-Wcast-qual]
  599 |                         sgr = (struct sgrp *) sgr_locate (grp->gr_name);
      |                               ^

grpck.c:761:23: warning: cast discards ‘const’ qualifier from pointer target type [-Wcast-qual]
  761 |                 grp = (struct group *) gr_locate (sgr->sg_name);
      |                       ^
2022-01-03 15:09:17 +01:00
Christian Göttsche a74114fe34 Declare variable for string literal const
newgidmap.c:87:16: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
   87 |         policy = "deny\n";
      |                ^
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 946eb84182 Do not drop const qualifier for Basename
The private Basename() implementation does not modify its argument, so
a cast to a non-const char pointer is not necessary.

newgrp.c:790:39: warning: cast discards ‘const’ qualifier from pointer target type [-Wcast-qual]
  790 |         progbase = (char *) Basename ((char *) prog);
      |                                       ^
newgrp.c:790:20: warning: cast discards ‘const’ qualifier from pointer target type [-Wcast-qual]
  790 |         progbase = (char *) Basename ((char *) prog);
      |                    ^

shell.c:48:70: warning: cast discards ‘const’ qualifier from pointer target type [-Wcast-qual]
   48 |                 (void) snprintf (arg0, sizeof arg0, "-%s", Basename ((char *) file));
      |                                                                      ^
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
Christian Göttsche f84b8530c5 Declare file local functions static 2022-01-03 15:09:17 +01:00
Christian Göttsche dfe95bd08b selinux: only open selabel database once
Once opened, keep the selabel database open for further lookups.
Register an exit handler to close the database.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Acked-by: James Carter <jwcart2@gmail.com>
2021-05-06 16:58:10 +02:00
Christian Göttsche eb1d2de0e9 set_selinux_file_context(): prepare context for actual file type
Search the SELinux selabel database for the file type to be created.
Not specifying the file mode can cause an incorrect file context to be
returned.

Also prepare contexts in commonio_close() for the generic database
filename, not with the backup suffix appended, to ensure the desired
file context after the final rename.

Closes: #322

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Acked-by: James Carter <jwcart2@gmail.com>
2021-05-06 16:58:10 +02:00
Christian Göttsche 5f7649fb37 selinux.c: use modern selabel interface instead of deprecated matchpathcon
matchpathcon(3) is deprecated in favor of selabel_lookup(3).

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Acked-by: James Carter <jwcart2@gmail.com>
2021-05-06 16:58:10 +02:00
Christian Göttsche e367d111e5 selinux.c:reset_selinux_file_context(): do not fail in permissive mode
Return 0 on setfscreatecon(3) failure, like set_selinux_file_context().

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Acked-by: James Carter <jwcart2@gmail.com>
2021-05-06 16:58:10 +02:00
Christian Göttsche 95fd179683 selinux.c: do not use deprecated typedef and skip context translation
These retrieved contexts are just passed to libselinux functions and not
printed or otherwise made available to the outside, so a context
translation to human readable MCS/MLS labels is not needed.
(see man:setrans.conf(5))

The typedef security_context_t is deprecated, see
https://github.com/SELinuxProject/selinux/commit/9eb9c9327563014ad6a807814e7975424642d5b9

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Acked-by: James Carter <jwcart2@gmail.com>
2021-05-06 16:58:10 +02:00
Christian Göttsche c0aa8a876e vipw[selinux]: do not use deprecated typedef and skip context translation
This retrieved context is just passed to libselinux functions and not
printed or otherwise made available to the outside, so a context
translation to human readable MCS/MLS labels is not needed.
(see man:setrans.conf(5))

The typedef security_context_t is deprecated, see
https://github.com/SELinuxProject/selinux/commit/9eb9c9327563014ad6a807814e7975424642d5b9

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Acked-by: James Carter <jwcart2@gmail.com>
2021-05-06 16:58:10 +02:00
Christian Göttsche 6e4b2fe25d struct commonio_db[selinux]: do not use deprecated type security_context_t
The typedef security_context_t is deprecated, see
https://github.com/SELinuxProject/selinux/commit/9eb9c9327563014ad6a807814e7975424642d5b9

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Acked-by: James Carter <jwcart2@gmail.com>
2021-05-06 16:58:10 +02:00
Christian Göttsche cbd2472b7c migrate to new SELinux api
Using hard-coded access vector ids is deprecated and can lead to issues with custom SELinux policies.
Switch to `selinux_check_access()`.

Also use the libselinux log callback and log if available to audit.
This makes it easier for users to catch SELinux denials.

Drop legacy shortcut logic for passwd, which avoided a SELinux check if uid 0 changes a password of a user which username equals the current SELinux user identifier.
Nowadays usernames rarely match SELinux user identifiers and the benefit of skipping a SELinux check is negligible.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
2019-10-22 14:56:31 +02:00