Commit Graph

6 Commits

Author SHA1 Message Date
Skyler Ferrante
e6c2e43937 Hardcoding Prog to known value
See #959. We now set Prog (program name) based on hardcoded value instead
of argv[0]. This is to help prevent escape sequence injection.
2024-03-07 22:23:04 +01:00
Alejandro Colomar
f14670ee1a lib/, src/: Replace strtou[l]l(3) by strtou[l]l_noneg()
strtou[l]l(3) silently converts negative numbers into positive.  This
behavior is wrong: a negative value should be parsed as a negative
value, which would underflow unsigned (long) long, and so would return
the smallest possible value, 0, and set errno to ERANGE to report an
error.

Reviewed-by: Iker Pedrosa <ipedrosa@redhat.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2024-01-22 17:17:15 -06:00
Alejandro Colomar
1c464d9a2d lib/, src/: Fix error handling after strto[u]l[l](3)
-  Set errno = 0 before the call.  Otherwise, it may contain anything.
-  ERANGE is not the only possible errno value of these functions.  They
   can also set it to EINVAL.
-  Any errno value after these calls is bad; just compare against 0.
-  Don't check for the return value; just errno.  This function is
   guaranteed to not modify errno on success (POSIX).
-  Check endptr == str, which may or may not set EINVAL.

Suggested-by: Iker Pedrosa <ipedrosa@redhat.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2023-12-04 12:21:55 +01:00
Serge Hallyn
79157cbad8 Make shadow_logfd and Prog not extern
Closes #444
Closes #465

Signed-off-by: Serge Hallyn <serge@hallyn.com>
2021-12-23 15:18:07 -06:00
Serge Hallyn
2b22a6909d libsubid: don't print error messages on stderr by default
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>
2021-05-15 12:38:55 -05:00
Serge Hallyn
8492dee663 subids: support nsswitch
Closes #154

When starting any operation to do with subuid delegation, check
nsswitch for a module to use.  If none is specified, then use
the traditional /etc/subuid and /etc/subgid files.

Currently only one module is supported, and there is no fallback
to the files on errors.  Several possibilities could be considered:

1. in case of connection error, fall back to files
2. in case of unknown user, also fall back to files

etc...

When non-files nss module is used, functions to edit the range
are not supported.  It may make sense to support it, but it also
may make sense to require another tool to be used.

libsubordinateio also uses the nss_ helpers.  This is how for instance
lxc could easily be converted to supporting nsswitch.

Add a set of test cases, including a dummy libsubid_zzz module.  This
hardcodes values such that:

'ubuntu' gets 200000 - 300000
'user1' gets 100000 - 165536
'error' emulates an nss module error
'unknown' emulates a user unknown to the nss module
'conn' emulates a connection error ot the nss module

Changes to libsubid:

Change the list_owner_ranges api: return a count instead of making the array
null terminated.

This is a breaking change, so bump the libsubid abi major number.

Rename free_subuid_range and free_subgid_range to ungrant_subuid_range,
because otherwise it's confusing with free_subid_ranges which frees
    memory.

Run libsubid tests in jenkins

Switch argument order in find_subid_owners

Move the db locking into subordinateio.c

Signed-off-by: Serge Hallyn <serge@hallyn.com>
2021-04-16 21:02:37 -05:00