hush/loginutils/adduser.c
Denys Vlasenko 95dee81a46 loginutils/*: convert to new-style "one file" applets
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2015-10-19 01:20:36 +02:00

329 lines
10 KiB
C

/* vi: set sw=4 ts=4: */
/*
* adduser - add users to /etc/passwd and /etc/shadow
*
* Copyright (C) 1999 by Lineo, inc. and John Beppu
* Copyright (C) 1999,2000,2001 by John Beppu <beppu@codepoet.org>
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
//config:config ADDUSER
//config: bool "adduser"
//config: default y
//config: help
//config: Utility for creating a new user account.
//config:
//config:config FEATURE_ADDUSER_LONG_OPTIONS
//config: bool "Enable long options"
//config: default y
//config: depends on ADDUSER && LONG_OPTS
//config: help
//config: Support long options for the adduser applet.
//config:
//config:config FEATURE_CHECK_NAMES
//config: bool "Enable sanity check on user/group names in adduser and addgroup"
//config: default n
//config: depends on ADDUSER || ADDGROUP
//config: help
//config: Enable sanity check on user and group names in adduser and addgroup.
//config: To avoid problems, the user or group name should consist only of
//config: letters, digits, underscores, periods, at signs and dashes,
//config: and not start with a dash (as defined by IEEE Std 1003.1-2001).
//config: For compatibility with Samba machine accounts "$" is also supported
//config: at the end of the user or group name.
//config:
//config:config LAST_ID
//config: int "Last valid uid or gid for adduser and addgroup"
//config: depends on ADDUSER || ADDGROUP
//config: default 60000
//config: help
//config: Last valid uid or gid for adduser and addgroup
//config:
//config:config FIRST_SYSTEM_ID
//config: int "First valid system uid or gid for adduser and addgroup"
//config: depends on ADDUSER || ADDGROUP
//config: range 0 LAST_ID
//config: default 100
//config: help
//config: First valid system uid or gid for adduser and addgroup
//config:
//config:config LAST_SYSTEM_ID
//config: int "Last valid system uid or gid for adduser and addgroup"
//config: depends on ADDUSER || ADDGROUP
//config: range FIRST_SYSTEM_ID LAST_ID
//config: default 999
//config: help
//config: Last valid system uid or gid for adduser and addgroup
//applet:IF_ADDUSER(APPLET(adduser, BB_DIR_USR_SBIN, BB_SUID_DROP))
//kbuild:lib-$(CONFIG_ADDUSER) += adduser.o
//usage:#define adduser_trivial_usage
//usage: "[OPTIONS] USER [GROUP]"
//usage:#define adduser_full_usage "\n\n"
//usage: "Create new user, or add USER to GROUP\n"
//usage: "\n -h DIR Home directory"
//usage: "\n -g GECOS GECOS field"
//usage: "\n -s SHELL Login shell"
//usage: "\n -G GRP Add user to existing group"
//usage: "\n -S Create a system user"
//usage: "\n -D Don't assign a password"
//usage: "\n -H Don't create home directory"
//usage: "\n -u UID User id"
//usage: "\n -k SKEL Skeleton directory (/etc/skel)"
#include "libbb.h"
#if CONFIG_LAST_SYSTEM_ID < CONFIG_FIRST_SYSTEM_ID
#error Bad LAST_SYSTEM_ID or FIRST_SYSTEM_ID in .config
#endif
#if CONFIG_LAST_ID < CONFIG_LAST_SYSTEM_ID
#error Bad LAST_ID or LAST_SYSTEM_ID in .config
#endif
/* #define OPT_HOME (1 << 0) */ /* unused */
/* #define OPT_GECOS (1 << 1) */ /* unused */
#define OPT_SHELL (1 << 2)
#define OPT_GID (1 << 3)
#define OPT_DONT_SET_PASS (1 << 4)
#define OPT_SYSTEM_ACCOUNT (1 << 5)
#define OPT_DONT_MAKE_HOME (1 << 6)
#define OPT_UID (1 << 7)
#define OPT_SKEL (1 << 8)
/* remix */
/* recoded such that the uid may be passed in *p */
static void passwd_study(struct passwd *p)
{
int max = CONFIG_LAST_ID;
if (getpwnam(p->pw_name)) {
bb_error_msg_and_die("%s '%s' in use", "user", p->pw_name);
/* this format string is reused in adduser and addgroup */
}
if (!(option_mask32 & OPT_UID)) {
if (option_mask32 & OPT_SYSTEM_ACCOUNT) {
p->pw_uid = CONFIG_FIRST_SYSTEM_ID;
max = CONFIG_LAST_SYSTEM_ID;
} else {
p->pw_uid = CONFIG_LAST_SYSTEM_ID + 1;
}
}
/* check for a free uid (and maybe gid) */
while (getpwuid(p->pw_uid) || (p->pw_gid == (gid_t)-1 && getgrgid(p->pw_uid))) {
if (option_mask32 & OPT_UID) {
/* -u N, cannot pick uid other than N: error */
bb_error_msg_and_die("%s '%s' in use", "uid", itoa(p->pw_uid));
/* this format string is reused in adduser and addgroup */
}
if (p->pw_uid == max) {
bb_error_msg_and_die("no %cids left", 'u');
/* this format string is reused in adduser and addgroup */
}
p->pw_uid++;
}
if (p->pw_gid == (gid_t)-1) {
p->pw_gid = p->pw_uid; /* new gid = uid */
if (getgrnam(p->pw_name)) {
bb_error_msg_and_die("%s '%s' in use", "group", p->pw_name);
/* this format string is reused in adduser and addgroup */
}
}
}
static int addgroup_wrapper(struct passwd *p, const char *group_name)
{
char *argv[6];
argv[0] = (char*)"addgroup";
if (group_name) {
/* Add user to existing group */
argv[1] = (char*)"--";
argv[2] = p->pw_name;
argv[3] = (char*)group_name;
argv[4] = NULL;
} else {
/* Add user to his own group with the first free gid
* found in passwd_study.
*/
#if ENABLE_FEATURE_ADDGROUP_LONG_OPTIONS || !ENABLE_ADDGROUP
/* We try to use --gid, not -g, because "standard" addgroup
* has no short option -g, it has only long --gid.
*/
argv[1] = (char*)"--gid";
#else
/* Breaks if system in fact does NOT use busybox addgroup */
argv[1] = (char*)"-g";
#endif
argv[2] = utoa(p->pw_gid);
argv[3] = (char*)"--";
argv[4] = p->pw_name;
argv[5] = NULL;
}
return spawn_and_wait(argv);
}
static void passwd_wrapper(const char *login_name) NORETURN;
static void passwd_wrapper(const char *login_name)
{
BB_EXECLP("passwd", "passwd", "--", login_name, NULL);
bb_error_msg_and_die("can't execute passwd, you must set password manually");
}
#if ENABLE_FEATURE_ADDUSER_LONG_OPTIONS
static const char adduser_longopts[] ALIGN1 =
"home\0" Required_argument "h"
"gecos\0" Required_argument "g"
"shell\0" Required_argument "s"
"ingroup\0" Required_argument "G"
"disabled-password\0" No_argument "D"
"empty-password\0" No_argument "D"
"system\0" No_argument "S"
"no-create-home\0" No_argument "H"
"uid\0" Required_argument "u"
"skel\0" Required_argument "k"
;
#endif
/*
* adduser will take a login_name as its first parameter.
* home, shell, gecos:
* can be customized via command-line parameters.
*/
int adduser_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int adduser_main(int argc UNUSED_PARAM, char **argv)
{
struct passwd pw;
const char *usegroup = NULL;
char *p;
unsigned opts;
char *uid;
const char *skel = "/etc/skel";
#if ENABLE_FEATURE_ADDUSER_LONG_OPTIONS
applet_long_options = adduser_longopts;
#endif
/* got root? */
if (geteuid()) {
bb_error_msg_and_die(bb_msg_perm_denied_are_you_root);
}
pw.pw_gecos = (char *)"Linux User,,,";
/* We assume that newly created users "inherit" root's shell setting */
pw.pw_shell = (char *)get_shell_name();
pw.pw_dir = NULL;
/* at least one and at most two non-option args */
/* disable interactive passwd for system accounts */
opt_complementary = "-1:?2:SD";
opts = getopt32(argv, "h:g:s:G:DSHu:k:", &pw.pw_dir, &pw.pw_gecos, &pw.pw_shell, &usegroup, &uid, &skel);
if (opts & OPT_UID)
pw.pw_uid = xatou_range(uid, 0, CONFIG_LAST_ID);
argv += optind;
pw.pw_name = argv[0];
if (!opts && argv[1]) {
/* if called with two non-option arguments, adduser
* will add an existing user to an existing group.
*/
return addgroup_wrapper(&pw, argv[1]);
}
/* fill in the passwd struct */
die_if_bad_username(pw.pw_name);
if (!pw.pw_dir) {
/* create string for $HOME if not specified already */
pw.pw_dir = xasprintf("/home/%s", argv[0]);
}
pw.pw_passwd = (char *)"x";
if (opts & OPT_SYSTEM_ACCOUNT) {
if (!usegroup) {
usegroup = "nogroup";
}
if (!(opts & OPT_SHELL)) {
pw.pw_shell = (char *) "/bin/false";
}
}
pw.pw_gid = usegroup ? xgroup2gid(usegroup) : -1; /* exits on failure */
/* make sure everything is kosher and setup uid && maybe gid */
passwd_study(&pw);
p = xasprintf("x:%u:%u:%s:%s:%s",
(unsigned) pw.pw_uid, (unsigned) pw.pw_gid,
pw.pw_gecos, pw.pw_dir, pw.pw_shell);
if (update_passwd(bb_path_passwd_file, pw.pw_name, p, NULL) < 0) {
return EXIT_FAILURE;
}
if (ENABLE_FEATURE_CLEAN_UP)
free(p);
#if ENABLE_FEATURE_SHADOWPASSWDS
/* /etc/shadow fields:
* 1. username
* 2. encrypted password
* 3. last password change (unix date (unix time/24*60*60))
* 4. minimum days required between password changes
* 5. maximum days password is valid
* 6. days before password is to expire that user is warned
* 7. days after password expires that account is disabled
* 8. unix date when login expires (i.e. when it may no longer be used)
*/
/* fields: 2 3 4 5 6 78 */
p = xasprintf("!:%u:0:99999:7:::", (unsigned)(time(NULL)) / (24*60*60));
/* ignore errors: if file is missing we suppose admin doesn't want it */
update_passwd(bb_path_shadow_file, pw.pw_name, p, NULL);
if (ENABLE_FEATURE_CLEAN_UP)
free(p);
#endif
/* add to group */
addgroup_wrapper(&pw, usegroup);
/* clear the umask for this process so it doesn't
* screw up the permissions on the mkdir and chown. */
umask(0);
if (!(opts & OPT_DONT_MAKE_HOME)) {
/* set the owner and group so it is owned by the new user,
* then fix up the permissions to 2755. Can't do it before
* since chown will clear the setgid bit */
int mkdir_err = mkdir(pw.pw_dir, 0755);
if (mkdir_err == 0) {
/* New home. Copy /etc/skel to it */
const char *args[] = {
"chown",
"-R",
xasprintf("%u:%u", (int)pw.pw_uid, (int)pw.pw_gid),
pw.pw_dir,
NULL
};
/* Be silent on any errors (like: no /etc/skel) */
if (!(opts & OPT_SKEL))
logmode = LOGMODE_NONE;
copy_file(skel, pw.pw_dir, FILEUTILS_RECUR);
logmode = LOGMODE_STDIO;
chown_main(4, (char**)args);
}
if ((mkdir_err != 0 && errno != EEXIST)
|| chown(pw.pw_dir, pw.pw_uid, pw.pw_gid) != 0
|| chmod(pw.pw_dir, 02755) != 0 /* set setgid bit on homedir */
) {
bb_simple_perror_msg(pw.pw_dir);
}
}
if (!(opts & OPT_DONT_SET_PASS)) {
/* interactively set passwd */
passwd_wrapper(pw.pw_name);
}
return EXIT_SUCCESS;
}