acl-util.c revision 50d9e46dbb8400d4570781728c63b151d9ca982b
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2011,2013 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <assert.h>
#include <errno.h>
#include <stdbool.h>
#include "acl-util.h"
#include "util.h"
#include "strv.h"
int acl_find_uid(acl_t acl, uid_t uid, acl_entry_t *entry) {
acl_entry_t i;
int found;
assert(acl);
assert(entry);
for (found = acl_get_entry(acl, ACL_FIRST_ENTRY, &i);
found > 0;
found = acl_get_entry(acl, ACL_NEXT_ENTRY, &i)) {
acl_tag_t tag;
uid_t *u;
bool b;
if (acl_get_tag_type(i, &tag) < 0)
return -errno;
if (tag != ACL_USER)
continue;
u = acl_get_qualifier(i);
if (!u)
return -errno;
b = *u == uid;
acl_free(u);
if (b) {
*entry = i;
return 1;
}
}
if (found < 0)
return -errno;
return 0;
}
int calc_acl_mask_if_needed(acl_t *acl_p) {
acl_entry_t i;
int found;
assert(acl_p);
for (found = acl_get_entry(*acl_p, ACL_FIRST_ENTRY, &i);
found > 0;
found = acl_get_entry(*acl_p, ACL_NEXT_ENTRY, &i)) {
acl_tag_t tag;
if (acl_get_tag_type(i, &tag) < 0)
return -errno;
if (tag == ACL_MASK)
return 0;
}
if (found < 0)
return -errno;
if (acl_calc_mask(acl_p) < 0)
return -errno;
return 0;
}
int search_acl_groups(char*** dst, const char* path, bool* belong) {
acl_t acl;
assert(path);
assert(belong);
acl = acl_get_file(path, ACL_TYPE_DEFAULT);
if (acl) {
acl_entry_t entry;
int r;
r = acl_get_entry(acl, ACL_FIRST_ENTRY, &entry);
while (r > 0) {
acl_tag_t tag;
gid_t *gid;
char *name;
r = acl_get_tag_type(entry, &tag);
if (r < 0)
break;
if (tag != ACL_GROUP)
goto next;
gid = acl_get_qualifier(entry);
if (!gid)
break;
if (in_gid(*gid) > 0) {
*belong = true;
break;
}
name = gid_to_name(*gid);
if (!name) {
acl_free(acl);
return log_oom();
}
r = strv_consume(dst, name);
if (r < 0) {
acl_free(acl);
return log_oom();
}
next:
r = acl_get_entry(acl, ACL_NEXT_ENTRY, &entry);
}
acl_free(acl);
}
return 0;
}
int parse_acl(char *text, acl_t *acl_access, acl_t *acl_default, bool want_mask) {
_cleanup_free_ char **a = NULL, **d = NULL; /* strings are not be freed */
_cleanup_strv_free_ char **split;
char **entry;
int r = -EINVAL;
_cleanup_(acl_freep) acl_t a_acl = NULL, d_acl = NULL;
split = strv_split(text, ",");
if (!split)
return log_oom();
STRV_FOREACH(entry, split) {
char *p;
p = startswith(*entry, "default:");
if (!p)
p = startswith(*entry, "d:");
if (p)
r = strv_push(&d, p);
else
r = strv_push(&a, *entry);
}
if (r < 0)
return r;
if (!strv_isempty(a)) {
_cleanup_free_ char *join;
join = strv_join(a, ",");
if (!join)
return -ENOMEM;
a_acl = acl_from_text(join);
if (!a_acl)
return -EINVAL;
if (want_mask) {
r = calc_acl_mask_if_needed(&a_acl);
if (r < 0)
return r;
}
}
if (!strv_isempty(d)) {
_cleanup_free_ char *join;
join = strv_join(d, ",");
if (!join)
return -ENOMEM;
d_acl = acl_from_text(join);
if (!d_acl)
return -EINVAL;
if (want_mask) {
r = calc_acl_mask_if_needed(&d_acl);
if (r < 0)
return r;
}
}
*acl_access = a_acl;
*acl_default = d_acl;
a_acl = d_acl = NULL;
return 0;
}
int acls_for_file(const char *path, acl_type_t type, acl_t new, acl_t *acl) {
_cleanup_(acl_freep) acl_t old;
acl_entry_t i;
int found, r;
old = acl_get_file(path, type);
if (!old)
return -errno;
for (found = acl_get_entry(new, ACL_FIRST_ENTRY, &i);
found > 0;
found = acl_get_entry(new, ACL_NEXT_ENTRY, &i)) {
acl_entry_t j;
if (acl_create_entry(&old, &j) < 0)
return -errno;
if (acl_copy_entry(j, i) < 0)
return -errno;
}
r = calc_acl_mask_if_needed(&old);
if (r < 0)
return r;
*acl = old;
old = NULL;
return 0;
}