65c2617140
- Use an allocation of 65536 uids and gids to allow for POSIX-compliant user owned namespaces. - Don't allocate a uid/gid map to system users. Unfortunately checking for --system isn't quite enough as some distribution wrappers always call useradd without --system and take care of choosing a uid and gid themselves, so also check whether the requested uid/gid is in the user range. This is taken from a patch I wrote for Ubuntu a couple years ago and which somehow didn't make it upstream. Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
87 lines
3.0 KiB
C
87 lines
3.0 KiB
C
/*
|
|
* Copyright (c) 2012 Eric Biederman
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. The name of the copyright holders or contributors may not be used to
|
|
* endorse or promote products derived from this software without
|
|
* specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
|
|
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
|
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
|
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <config.h>
|
|
|
|
#ifdef ENABLE_SUBIDS
|
|
|
|
#include <assert.h>
|
|
#include <stdio.h>
|
|
#include <errno.h>
|
|
|
|
#include "prototypes.h"
|
|
#include "subordinateio.h"
|
|
#include "getdef.h"
|
|
|
|
/*
|
|
* find_new_sub_gids - Find a new unused range of GIDs.
|
|
*
|
|
* If successful, find_new_sub_gids provides a range of unused
|
|
* user IDs in the [SUB_GID_MIN:SUB_GID_MAX] range.
|
|
*
|
|
* Return 0 on success, -1 if no unused GIDs are available.
|
|
*/
|
|
int find_new_sub_gids (const char *owner,
|
|
gid_t *range_start, unsigned long *range_count)
|
|
{
|
|
unsigned long min, max;
|
|
unsigned long count;
|
|
gid_t start;
|
|
|
|
assert (range_start != NULL);
|
|
assert (range_count != NULL);
|
|
|
|
min = getdef_ulong ("SUB_GID_MIN", 100000UL);
|
|
max = getdef_ulong ("SUB_GID_MAX", 600100000UL);
|
|
count = getdef_ulong ("SUB_GID_COUNT", 65536);
|
|
|
|
if (min > max || count >= max || (min + count - 1) > max) {
|
|
(void) fprintf (stderr,
|
|
_("%s: Invalid configuration: SUB_GID_MIN (%lu),"
|
|
" SUB_GID_MAX (%lu), SUB_GID_COUNT (%lu)\n"),
|
|
Prog, min, max, count);
|
|
return -1;
|
|
}
|
|
|
|
start = sub_gid_find_free_range(min, max, count);
|
|
if (start == (gid_t)-1) {
|
|
fprintf (stderr,
|
|
_("%s: Can't get unique subordinate GID range\n"),
|
|
Prog);
|
|
SYSLOG ((LOG_WARN, "no more available subordinate GIDs on the system"));
|
|
return -1;
|
|
}
|
|
*range_start = start;
|
|
*range_count = count;
|
|
return 0;
|
|
}
|
|
#else /* !ENABLE_SUBIDS */
|
|
extern int errno; /* warning: ANSI C forbids an empty source file */
|
|
#endif /* !ENABLE_SUBIDS */
|
|
|