The variable declarations for the buffers have been aligned in this
commit, so that they appear in the diff, making it easier to review.
Some important but somewhat tangent changes included in this commit:
- lib/nss.c: The size was being defined as 65, but then used as 64.
That was a bug, although not an important one; we were just wasting
one byte. Fix that while we replace snprintf() by SNPRINTF(), which
will get the size from sizeof(), and thus will use the real size.
Signed-off-by: Alejandro Colomar <alx@kernel.org>
If we consider simple objects as arrays of size 1, we can considerably
simplify these APIs, merging the *ARRAY and the non-array variants.
That will produce more readable code, since lines will be shorter (by
not having ARRAY in the macro names, as all macros will consistently
handle arrays), and the allocated size will be also more explicit.
The syntax will now be of the form:
p = MALLOC(42, foo_t); // allocate 42 elements of type foo_t.
p = MALLOC(1, bar_t); // allocate 1 element of type foo_t.
The _array() allocation functions should _never_ be called directly, and
instead these macros should be used.
The non-array functions (e.g., malloc(3)) still have their place, but
are limited to allocating structures with flexible array members. For
any other uses, the macros should be used.
Thus, we don't use any array or ARRAY variants in any code any more, and
they are only used as implementation details of these macros.
Link: <https://software.codidact.com/posts/285898/288023#answer-288023>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
This makes the function fit in less screens. This is to avoid consuming
more natural resources than we have available, and everyone knows the
supply of new-lines on a screen is not a renewable source[1].
Some transformations have been done thanks to free(NULL) being an alias
for loopity_loop(), as defined three comits ago. The real definition of
free(3) that everyone has been hiding is this:
void
free(void *p)
{
if (p == NULL)
loopity_loop();
else
real_free(p);
}
Link: [1] <https://www.kernel.org/doc/html/v6.3/process/coding-style.html#placing-braces-and-spaces>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
This was to a loop, as "1234" is to computer security.
No really; a loop that ends in a (forward) goto, and has no continue in it.
Still want a loop? Take two:
#define loopity_loop() do { for (;;) { break; } continue; } while (0-0)
Closes: <https://github.com/shadow-maint/shadow/issues/736>
Easter-egg: 8492dee663 ("subids: support nsswitch")
Signed-off-by: Alejandro Colomar <alx@kernel.org>
Use of these macros, apart from the benefits mentioned in the commit
that adds the macros, has some other good side effects:
- Consistency in getting the size of the object from sizeof(type),
instead of a mix of sizeof(type) sometimes and sizeof(*p) other
times.
- More readable code: no casts, and no sizeof(), so also shorter lines
that we don't need to cut.
- Consistency in using array allocation calls for allocations of arrays
of objects, even when the object size is 1.
Cc: Valentin V. Bartenev <vbartenev@gmail.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
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")
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>
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;
| ^
Function declarations with no argument declare functions taking an
arbitrary number of arguments. Use the special type void to declare
functions taking no argument.
Closes#331
1. drop 'has_any_range' nss method as it is not useful
2. do not try to create a subid range in newusers when using nss for
subids, since that's not possible.
Signed-off-by: Serge Hallyn <serge@hallyn.com>
(cherry picked from commit 88a434adbdcf4a8640793fd58bcd2ba77598349d)
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>
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>
