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| -rw-r--r-- | Base/usr/share/man/man8/userdel.md | 43 | ||||
| -rw-r--r-- | Userland/userdel.cpp | 151 |
2 files changed, 194 insertions, 0 deletions
diff --git a/Base/usr/share/man/man8/userdel.md b/Base/usr/share/man/man8/userdel.md new file mode 100644 index 0000000000..745474ff86 --- /dev/null +++ b/Base/usr/share/man/man8/userdel.md @@ -0,0 +1,43 @@ +## Name + +userdel - delete a user account + +## Synopsis + +```**sh +# userdel [-r] <login> +``` + +## Description + +This program deletes a user account in the system. + +This program must be run as root. + +## Options + +* `-r`, `--remove`: Remove the home directory for this user if the directory exists. + +## Exit Values + +* 0 - Success +* 1 - Couldn't update the password file +* 6 - Specified user doesn't exist +* 12 - Couldn't remove home directory + +## Files + +* `/etc/passwd` - user information (such as UID and GID) in this file is deleted. +* `/home/` - user home directroy is deleted if the `-r` flag is specified. + +## Examples + +```sh +# userdel alice +# userdel -r alice +# userdel --remove alice +``` + +## See Also + +* [`useradd`(8)](useradd.md) diff --git a/Userland/userdel.cpp b/Userland/userdel.cpp new file mode 100644 index 0000000000..40d55c42fe --- /dev/null +++ b/Userland/userdel.cpp @@ -0,0 +1,151 @@ +/* + * Copyright (c) 2019-2020, Fei Wu <f.eiwu@yahoo.com> + * 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 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 HOLDER 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 <AK/String.h> +#include <AK/StringBuilder.h> +#include <LibCore/ArgsParser.h> +#include <ctype.h> +#include <dirent.h> +#include <errno.h> +#include <pwd.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/stat.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <unistd.h> + +int main(int argc, char** argv) +{ + const char* username = nullptr; + bool remove_home = false; + + Core::ArgsParser args_parser; + args_parser.add_option(remove_home, "Remove home directory", "remove", 'r'); + args_parser.add_positional_argument(username, "Login user identity (username)", "login"); + args_parser.parse(argc, argv); + + char temp_filename[] = "/etc/passwd.XXXXXX"; + auto fd = mkstemp(temp_filename); + if (fd == -1) { + perror("failed to create temporary file"); + return 1; + } + + FILE* temp_file = fdopen(fd, "w"); + if (!temp_file) { + perror("fdopen"); + if (unlink(temp_filename) < 0) { + perror("unlink"); + } + + return 1; + } + + bool user_exists = false; + String home_directory; + + int rc = 0; + setpwent(); + for (auto* pw = getpwent(); pw; pw = getpwent()) { + if (strcmp(pw->pw_name, username)) { + if (putpwent(pw, temp_file) != 0) { + perror("failed to put an entry in the temporary passwd file"); + rc = 1; + break; + } + } else { + user_exists = true; + if (remove_home) + home_directory = pw->pw_dir; + } + } + endpwent(); + + if (fclose(temp_file)) { + perror("fclose"); + if (!rc) + rc = 1; + } + + if (rc == 0 && !user_exists) { + fprintf(stderr, "specified user doesn't exist\n"); + rc = 6; + } + + if (rc == 0 && chmod(temp_filename, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH)) { + perror("chmod"); + rc = 1; + } + + if (rc == 0 && rename(temp_filename, "/etc/passwd") < 0) { + perror("failed to rename the temporary passwd file"); + rc = 1; + } + + if (rc) { + if (unlink(temp_filename) < 0) { + perror("unlink"); + } + return rc; + } + + if (remove_home) { + if (home_directory == "/") { + fprintf(stderr, "home directory is /, not deleted!\n"); + return 12; + } + + if (access(home_directory.characters(), F_OK) != -1) { + auto child = fork(); + + if (child < 0) { + perror("fork"); + return 12; + } + + if (!child) { + int rc = execl("/bin/rm", "rm", "-r", home_directory.characters(), nullptr); + ASSERT(rc < 0); + perror("execl"); + exit(127); + } + + int wstatus; + if (waitpid(child, &wstatus, 0) < 0) { + perror("waitpid"); + return 12; + } + if (WEXITSTATUS(wstatus)) { + fprintf(stderr, "failed to remove the home directory\n"); + return 12; + } + } + } + + return 0; +} |