/*
File: do_set.c
(Linux Access Control List Management)
Copyright (C) 1999, 2000
Andreas Gruenbacher, <a.gruenbacher@bestbits.at>
This program 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.
This program 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 this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include "config.h"
#include <stdio.h>
#include <errno.h>
#include <sys/acl.h>
#include <acl/libacl.h>
#include <stdlib.h>
#include <string.h>
#include <getopt.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <dirent.h>
#include <ftw.h>
#include "misc.h"
#include "sequence.h"
#include "do_set.h"
#include "parse.h"
#include "walk_tree.h"
extern const char *progname;
extern int opt_recalculate;
extern int opt_test;
extern int print_options;
acl_entry_t
find_entry(
acl_t acl,
acl_tag_t type,
id_t id)
{
acl_entry_t ent;
acl_tag_t e_type;
id_t *e_id_p;
if (acl_get_entry(acl, ACL_FIRST_ENTRY, &ent) != 1)
return NULL;
for(;;) {
acl_get_tag_type(ent, &e_type);
if (type == e_type) {
if (id != ACL_UNDEFINED_ID) {
e_id_p = acl_get_qualifier(ent);
if (e_id_p == NULL)
return NULL;
if (*e_id_p == id) {
acl_free(e_id_p);
return ent;
}
acl_free(e_id_p);
} else {
return ent;
}
}
if (acl_get_entry(acl, ACL_NEXT_ENTRY, &ent) != 1)
return NULL;
}
}
int
has_execute_perms(
acl_t acl)
{
acl_entry_t ent;
if (acl_get_entry(acl, ACL_FIRST_ENTRY, &ent) != 1)
return 0;
for(;;) {
acl_permset_t permset;
acl_get_permset(ent, &permset);
if (acl_get_perm(permset, ACL_EXECUTE) != 0)
return 1;
if (acl_get_entry(acl, ACL_NEXT_ENTRY, &ent) != 1)
return 0;
}
}
int
clone_entry(
acl_t from_acl,
acl_tag_t from_type,
acl_t *to_acl,
acl_tag_t to_type)
{
acl_entry_t from_entry, to_entry;
from_entry = find_entry(from_acl, from_type, ACL_UNDEFINED_ID);
if (from_entry) {
if (acl_create_entry(to_acl, &to_entry) != 0)
return -1;
acl_copy_entry(to_entry, from_entry);
acl_set_tag_type(to_entry, to_type);
return 0;
} else {
return 1;
}
}
void
print_test(
FILE *file,
const char *path_p,
const struct stat *st,
const acl_t acl,
const acl_t default_acl)
{
char *acl_text, *default_acl_text;
acl_text = acl_to_any_text(acl, NULL, ',', TEXT_ABBREVIATE);
default_acl_text =
acl_to_any_text(default_acl, "d:", ',', TEXT_ABBREVIATE);
fprintf(file, "%s: %s,%s\n", path_p,
acl_text ? acl_text : "*",
default_acl_text ? default_acl_text : "*");
acl_free(acl_text);
acl_free(default_acl_text);
}
static void
set_perm(
acl_entry_t ent,
mode_t perm)
{
acl_permset_t set;
acl_get_permset(ent, &set);
if (perm & CMD_PERM_READ)
acl_add_perm(set, ACL_READ);
else
acl_delete_perm(set, ACL_READ);
if (perm & CMD_PERM_WRITE)
acl_add_perm(set, ACL_WRITE);
else
acl_delete_perm(set, ACL_WRITE);
if (perm & CMD_PERM_EXECUTE)
acl_add_perm(set, ACL_EXECUTE);
else
acl_delete_perm(set, ACL_EXECUTE);
}
static int
retrieve_acl(
const char *path_p,
acl_type_t type,
const struct stat *st,
acl_t *old_acl,
acl_t *acl)
{
if (*acl)
return 0;
*acl = NULL;
if (type == ACL_TYPE_ACCESS || S_ISDIR(st->st_mode)) {
*old_acl = acl_get_file(path_p, type);
if (*old_acl == NULL && (errno == ENOSYS || errno == ENOTSUP)) {
if (type == ACL_TYPE_DEFAULT)
*old_acl = acl_init(0);
else
*old_acl = acl_from_mode(st->st_mode);
}
} else
*old_acl = acl_init(0);
if (*old_acl == NULL)
return -1;
*acl = acl_dup(*old_acl);
if (*acl == NULL)
return -1;
return 0;
}
static int
remove_extended_entries(
acl_t acl)
{
acl_entry_t ent, group_obj;
acl_permset_t mask_permset, group_obj_permset;
acl_tag_t tag;
int error;
/*
* Removing the ACL_MASK entry from the ACL results in
* increased permissions for the owning group if the
* ACL_GROUP_OBJ entry contains permissions not contained
* in the ACL_MASK entry. We remove these permissions from
* the ACL_GROUP_OBJ entry to avoid that.
*
* After removing the ACL, the file owner and the owning group
* therefore have the same permissions as before.
*/
ent = find_entry(acl, ACL_MASK, ACL_UNDEFINED_ID);
group_obj = find_entry(acl, ACL_GROUP_OBJ, ACL_UNDEFINED_ID);
if (ent && group_obj) {
if (!acl_get_permset(ent, &mask_permset) &&
!acl_get_permset(group_obj, &group_obj_permset)) {
if (!acl_get_perm(mask_permset, ACL_READ))
acl_delete_perm(group_obj_permset, ACL_READ);
if (!acl_get_perm(mask_permset, ACL_WRITE))
acl_delete_perm(group_obj_permset, ACL_WRITE);
if (!acl_get_perm(mask_permset, ACL_EXECUTE))
acl_delete_perm(group_obj_permset, ACL_EXECUTE);
}
}
error = acl_get_entry(acl, ACL_FIRST_ENTRY, &ent);
while (error == 1) {
acl_get_tag_type(ent, &tag);
switch(tag) {
case ACL_USER:
case ACL_GROUP:
case ACL_MASK:
acl_delete_entry(acl, ent);
break;
default:
break;
}
error = acl_get_entry(acl, ACL_NEXT_ENTRY, &ent);
}
if (error < 0)
return -1;
return 0;
}
#define RETRIEVE_ACL(type) do { \
error = retrieve_acl(path_p, type, st, old_xacl, xacl); \
if (error) \
goto fail; \
} while(0)
int
do_set(
const char *path_p,
const struct stat *st,
int walk_flags,
void *arg)
{
struct do_set_args *args = arg;
acl_t old_acl = NULL, old_default_acl = NULL;
acl_t acl = NULL, default_acl = NULL;
acl_t *xacl, *old_xacl;
acl_entry_t ent;
cmd_t cmd;
int which_entry;
int errors = 0, error;
char *acl_text;
int acl_modified = 0, default_acl_modified = 0;
int acl_mask_provided = 0, default_acl_mask_provided = 0;
if (walk_flags & WALK_TREE_FAILED) {
fprintf(stderr, "%s: %s: %s\n", progname, path_p, strerror(errno));
return 1;
}
/*
* Symlinks can never have ACLs, so when doing a physical walk, we
* skip symlinks altogether, and when doing a half-logical walk, we
* skip all non-toplevel symlinks.
*/
if ((walk_flags & WALK_TREE_SYMLINK) &&
((walk_flags & WALK_TREE_PHYSICAL) ||
!(walk_flags & (WALK_TREE_TOPLEVEL | WALK_TREE_LOGICAL))))
return 0;
/* Execute the commands in seq (read ACLs on demand) */
error = seq_get_cmd(args->seq, SEQ_FIRST_CMD, &cmd);
if (error == 0)
return 0;
while (error == 1) {
mode_t perm = cmd->c_perm;
if (cmd->c_type == ACL_TYPE_ACCESS) {
xacl = &acl;
old_xacl = &old_acl;
acl_modified = 1;
if (cmd->c_tag == ACL_MASK)
acl_mask_provided = 1;
} else {
xacl = &default_acl;
old_xacl = &old_default_acl;
default_acl_modified = 1;
if (cmd->c_tag == ACL_MASK)
default_acl_mask_provided = 1;
}
RETRIEVE_ACL(cmd->c_type);
/* Check for `X', and replace with `x' as appropriate. */
if (perm & CMD_PERM_COND_EXECUTE) {
perm &= ~CMD_PERM_COND_EXECUTE;
if (S_ISDIR(st->st_mode) || has_execute_perms(*xacl))
perm |= CMD_PERM_EXECUTE;
}
switch(cmd->c_cmd) {
case CMD_ENTRY_REPLACE:
ent = find_entry(*xacl, cmd->c_tag, cmd->c_id);
if (!ent) {
if (acl_create_entry(xacl, &ent) != 0)
goto fail;
acl_set_tag_type(ent, cmd->c_tag);
if (cmd->c_id != ACL_UNDEFINED_ID)
acl_set_qualifier(ent,
&cmd->c_id);
}
set_perm(ent, perm);
break;
case CMD_REMOVE_ENTRY:
ent = find_entry(*xacl, cmd->c_tag, cmd->c_id);
if (ent)
acl_delete_entry(*xacl, ent);
else
/* ignore */;
break;
case CMD_REMOVE_EXTENDED_ACL:
remove_extended_entries(acl);
break;
case CMD_REMOVE_ACL:
acl_free(*xacl);
*xacl = acl_init(5);
if (!*xacl)
goto fail;
break;
default:
errno = EINVAL;
goto fail;
}
error = seq_get_cmd(args->seq, SEQ_NEXT_CMD, &cmd);
}
if (error < 0)
goto fail;
/* Try to fill in missing entries */
if (default_acl && acl_entries(default_acl) != 0) {
xacl = &acl;
old_xacl = &old_acl;
if (!find_entry(default_acl, ACL_USER_OBJ, ACL_UNDEFINED_ID)) {
if (!acl)
RETRIEVE_ACL(ACL_TYPE_ACCESS);
clone_entry(acl, ACL_USER_OBJ,
&default_acl, ACL_USER_OBJ);
}
if (!find_entry(default_acl, ACL_GROUP_OBJ, ACL_UNDEFINED_ID)) {
if (!acl)
RETRIEVE_ACL(ACL_TYPE_ACCESS);
clone_entry(acl, ACL_GROUP_OBJ,
&default_acl, ACL_GROUP_OBJ);
}
if (!find_entry(default_acl, ACL_OTHER, ACL_UNDEFINED_ID)) {
if (!acl)
RETRIEVE_ACL(ACL_TYPE_ACCESS);
clone_entry(acl, ACL_OTHER,
&default_acl, ACL_OTHER);
}
}
/* update mask entries and check if ACLs are valid */
if (acl && acl_modified) {
if (acl_equiv_mode(acl, NULL) != 0) {
if (!acl_mask_provided &&
!find_entry(acl, ACL_MASK, ACL_UNDEFINED_ID))
clone_entry(acl, ACL_GROUP_OBJ,
&acl, ACL_MASK);
if (opt_recalculate != -1 &&
(!acl_mask_provided || opt_recalculate == 1))
acl_calc_mask(&acl);
}
error = acl_check(acl, &which_entry);
if (error < 0)
goto fail;
if (error > 0) {
acl_text = acl_to_any_text(acl, NULL, ',', 0);
fprintf(stderr, _("%s: %s: Malformed access ACL "
"`%s': %s at entry %d\n"), progname, path_p,
acl_text, acl_error(error), which_entry+1);
acl_free(acl_text);
errors++;
goto cleanup;
}
}
if (default_acl && acl_entries(default_acl) != 0 &&
default_acl_modified) {
if (acl_equiv_mode(default_acl, NULL) != 0) {
if (!default_acl_mask_provided &&
!find_entry(default_acl,ACL_MASK,ACL_UNDEFINED_ID))
clone_entry(default_acl, ACL_GROUP_OBJ,
&default_acl, ACL_MASK);
if (opt_recalculate != -1 &&
(!default_acl_mask_provided ||
opt_recalculate == 1))
acl_calc_mask(&default_acl);
}
error = acl_check(default_acl, &which_entry);
if (error < 0)
goto fail;
if (error > 0) {
acl_text = acl_to_any_text(default_acl, NULL, ',', 0);
fprintf(stderr, _("%s: %s: Malformed default ACL "
"`%s': %s at entry %d\n"),
progname, path_p, acl_text,
acl_error(error), which_entry+1);
acl_free(acl_text);
errors++;
goto cleanup;
}
}
/* Only directores can have default ACLs */
if (default_acl && !S_ISDIR(st->st_mode) && (walk_flags & WALK_TREE_RECURSIVE)) {
/* In recursive mode, ignore default ACLs for files */
acl_free(default_acl);
default_acl = NULL;
}
/* check which ACLs have changed */
if (acl && old_acl && acl_cmp(old_acl, acl) == 0) {
acl_free(acl);
acl = NULL;
}
if ((default_acl && old_default_acl &&
acl_cmp(old_default_acl, default_acl) == 0)) {
acl_free(default_acl);
default_acl = NULL;
}
/* update the file system */
if (opt_test) {
print_test(stdout, path_p, st,
acl, default_acl);
goto cleanup;
}
if (acl) {
int equiv_mode;
mode_t mode = 0;
equiv_mode = acl_equiv_mode(acl, &mode);
if (acl_set_file(path_p, ACL_TYPE_ACCESS, acl) != 0) {
if (errno == ENOSYS || errno == ENOTSUP) {
if (equiv_mode != 0)
goto fail;
else {
struct stat st;
if (stat(path_p, &st) != 0)
goto fail;
mode |= st.st_mode & 07000;
if (chmod(path_p, mode) != 0)
goto fail;
}
} else
goto fail;
}
args->mode = mode;
}
if (default_acl) {
if (S_ISDIR(st->st_mode)) {
if (acl_entries(default_acl) == 0) {
if (acl_delete_def_file(path_p) != 0 &&
errno != ENOSYS && errno != ENOTSUP)
goto fail;
} else {
if (acl_set_file(path_p, ACL_TYPE_DEFAULT,
default_acl) != 0)
goto fail;
}
} else {
if (acl_entries(default_acl) != 0) {
fprintf(stderr, _("%s: %s: Only directories "
"can have default ACLs\n"),
progname, path_p);
errors++;
goto cleanup;
}
}
}
error = 0;
cleanup:
if (acl)
acl_free(acl);
if (old_acl)
acl_free(old_acl);
if (default_acl)
acl_free(default_acl);
if (old_default_acl)
acl_free(old_default_acl);
return errors;
fail:
fprintf(stderr, "%s: %s: %s\n", progname, path_p, strerror(errno));
errors++;
goto cleanup;
}