169 lines
4.5 KiB
C
169 lines
4.5 KiB
C
/*-
|
|
* SPDX-License-Identifier: BSD-2-Clause
|
|
*
|
|
* Copyright (C) 1996
|
|
* David L. Nugent. All rights reserved.
|
|
*
|
|
* 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.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY DAVID L. NUGENT 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 DAVID L. NUGENT 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 <sys/param.h>
|
|
#include <sys/mount.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/wait.h>
|
|
|
|
#include <dirent.h>
|
|
#include <err.h>
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <libgen.h>
|
|
#include <libutil.h>
|
|
#include <spawn.h>
|
|
#include <stdbool.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
|
|
#include "pwupd.h"
|
|
|
|
static bool try_dataset_remove(const char *home);
|
|
extern char **environ;
|
|
|
|
/*
|
|
* "rm -r" a directory tree. If the top-level directory cannot be removed
|
|
* due to EBUSY, indicating that it is a ZFS dataset, and we have emptied
|
|
* it, destroy the dataset. Return true if any files or directories
|
|
* remain.
|
|
*/
|
|
bool
|
|
rm_r(int rootfd, const char *path, uid_t uid)
|
|
{
|
|
int dirfd;
|
|
DIR *d;
|
|
struct dirent *e;
|
|
struct stat st;
|
|
const char *fullpath;
|
|
bool skipped = false;
|
|
|
|
fullpath = path;
|
|
if (*path == '/')
|
|
path++;
|
|
|
|
dirfd = openat(rootfd, path, O_DIRECTORY);
|
|
if (dirfd == -1) {
|
|
return (true);
|
|
}
|
|
|
|
d = fdopendir(dirfd);
|
|
if (d == NULL) {
|
|
(void)close(dirfd);
|
|
return (true);
|
|
}
|
|
while ((e = readdir(d)) != NULL) {
|
|
if (strcmp(e->d_name, ".") == 0 || strcmp(e->d_name, "..") == 0)
|
|
continue;
|
|
|
|
if (fstatat(dirfd, e->d_name, &st, AT_SYMLINK_NOFOLLOW) != 0)
|
|
continue;
|
|
if (S_ISDIR(st.st_mode)) {
|
|
if (rm_r(dirfd, e->d_name, uid) == true)
|
|
skipped = true;
|
|
} else if (S_ISLNK(st.st_mode) || st.st_uid == uid)
|
|
unlinkat(dirfd, e->d_name, 0);
|
|
else
|
|
skipped = true;
|
|
}
|
|
closedir(d);
|
|
if (fstatat(rootfd, path, &st, AT_SYMLINK_NOFOLLOW) != 0)
|
|
return (skipped);
|
|
if (S_ISLNK(st.st_mode)) {
|
|
if (unlinkat(rootfd, path, 0) == -1)
|
|
skipped = true;
|
|
} else if (st.st_uid == uid) {
|
|
if (unlinkat(rootfd, path, AT_REMOVEDIR) == -1) {
|
|
if (errno == EBUSY && skipped == false)
|
|
skipped = try_dataset_remove(fullpath);
|
|
else
|
|
skipped = true;
|
|
}
|
|
} else
|
|
skipped = true;
|
|
|
|
return (skipped);
|
|
}
|
|
|
|
/*
|
|
* If the home directory is a ZFS dataset, attempt to destroy it.
|
|
* Return true if the dataset is not destroyed.
|
|
* This would be more straightforward as a shell script.
|
|
*/
|
|
static bool
|
|
try_dataset_remove(const char *path)
|
|
{
|
|
bool skipped = true;
|
|
struct statfs stat;
|
|
const char *argv[] = {
|
|
"/sbin/zfs",
|
|
"destroy",
|
|
NULL,
|
|
NULL
|
|
};
|
|
int status;
|
|
pid_t pid;
|
|
|
|
/* see if this is an absolute path (top-level directory) */
|
|
if (*path != '/')
|
|
return (skipped);
|
|
/* see if ZFS is loaded */
|
|
if (kld_isloaded("zfs") == 0)
|
|
return (skipped);
|
|
/* This won't work if root dir is not / (-R option) */
|
|
if (strcmp(conf.rootdir, "/") != 0) {
|
|
warnx("cannot destroy home dataset when -R was used");
|
|
return (skipped);
|
|
}
|
|
/* if so, find dataset name */
|
|
if (statfs(path, &stat) != 0) {
|
|
warn("statfs %s", path);
|
|
return (skipped);
|
|
}
|
|
/*
|
|
* Check that the path refers to the dataset itself,
|
|
* not a subdirectory.
|
|
*/
|
|
if (strcmp(stat.f_mntonname, path) != 0)
|
|
return (skipped);
|
|
argv[2] = stat.f_mntfromname;
|
|
if ((skipped = posix_spawn(&pid, argv[0], NULL, NULL,
|
|
(char *const *) argv, environ)) != 0) {
|
|
warn("Failed to execute '%s %s %s'",
|
|
argv[0], argv[1], argv[2]);
|
|
} else {
|
|
if (waitpid(pid, &status, 0) != -1 && status != 0) {
|
|
warnx("'%s %s %s' exit status %d\n",
|
|
argv[0], argv[1], argv[2], status);
|
|
}
|
|
}
|
|
return (skipped);
|
|
}
|