diff options
Diffstat (limited to 'usr.sbin/pw/rm_r.c')
| -rw-r--r-- | usr.sbin/pw/rm_r.c | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/usr.sbin/pw/rm_r.c b/usr.sbin/pw/rm_r.c new file mode 100644 index 000000000000..f25da8ce6ad3 --- /dev/null +++ b/usr.sbin/pw/rm_r.c @@ -0,0 +1,168 @@ +/*- + * 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); +} |