diff options
Diffstat (limited to 'adduser.c')
| -rw-r--r-- | adduser.c | 366 |
1 files changed, 366 insertions, 0 deletions
diff --git a/adduser.c b/adduser.c new file mode 100644 index 0000000..6bd2c25 --- /dev/null +++ b/adduser.c @@ -0,0 +1,366 @@ +/* vi: set sw=4 ts=4: */ +/* + * adduser - add users to /etc/passwd and /etc/shadow + * + * + * Copyright (C) 1999 by Lineo, inc. + * Written by John Beppu <beppu@lineo.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 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 + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +#include <errno.h> +#include <fcntl.h> +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <shadow.h> +#include <time.h> +#include <unistd.h> +#include <sys/param.h> +#include <sys/stat.h> +#include <sys/types.h> +#include "busybox.h" +#include "pwd_grp/pwd.h" +#include "pwd_grp/grp.h" + +#define PASSWD_FILE "/etc/passwd" +#define SHADOW_FILE "/etc/gshadow" + +#if 0 +# define PASSWD_FILE "passwd" +# define SHADOW_FILE "shadow" +#endif + +/* structs __________________________ */ + +typedef struct { + uid_t u; + gid_t g; +} Id; + +/* data _____________________________ */ + +/* defaults : should this be in an external file? */ +static char *default_passwd = "x"; +static char *default_gecos = "Embedix User,,,"; +static char *default_home_prefix = "/home"; +static char *default_shell = "/bin/sh"; + +/* shadow in use? */ +static int shadow_enabled = 0; + +/* I was doing this all over the place */ +static FILE *fopen_wrapper(const char *filename, const char *mode) +{ + FILE *f; + + f = fopen(filename, mode); + if (f == NULL) { + fprintf(stderr, "adduser: %s: %s\n", filename, strerror(errno)); + } + return f; +} + +/* remix */ +/* EDR recoded such that the uid may be passed in *p */ +static int passwd_study(const char *filename, struct passwd *p) +{ + struct passwd *pw; + FILE *passwd; + + const int min = 500; + const int max = 65000; + + passwd = fopen_wrapper(filename, "r"); + if (!passwd) + return 4; + + /* EDR if uid is out of bounds, set to min */ + if ((p->pw_uid > max) || (p->pw_uid < min)) + p->pw_uid = min; + + /* stuff to do: + * make sure login isn't taken; + * find free uid and gid; + */ + while ((pw = fgetpwent(passwd))) { + if (strcmp(pw->pw_name, p->pw_name) == 0) { + /* return 0; */ + return 1; + } + if ((pw->pw_uid >= p->pw_uid) && (pw->pw_uid < max) + && (pw->pw_uid >= min)) { + p->pw_uid = pw->pw_uid + 1; + } + } + + /* EDR check for an already existing gid */ + while (getgrgid(p->pw_uid) != NULL) + p->pw_uid++; + + /* EDR also check for an existing group definition */ + if (getgrnam(p->pw_name) != NULL) + return 3; + + /* EDR bounds check */ + if ((p->pw_uid > max) || (p->pw_uid < min)) + return 2; + + /* EDR create new gid always = uid */ + p->pw_gid = p->pw_uid; + + /* return 1; */ + return 0; +} + +static void addgroup_wrapper(const char *login, gid_t gid) +{ + int argc = 4; + char *argv[] = { "addgroup", "-g", NULL, NULL }; + char group_id[8]; + char group_name[32]; + + strncpy(group_name, login, 32); + argv[3] = group_name; + sprintf(group_id, "%d", gid); + argv[2] = group_id; + addgroup_main(argc, argv); +} + +static void passwd_wrapper(const char *login) +{ + char *prog = "passwd"; + execlp(prog, prog, login, NULL); + error_msg_and_die("Failed to execute 'passwd', you must set the password for '%s' manually\n", login); +} + +/* + * pwd_to_spwd - create entries for new spwd structure + * + * pwd_to_spwd() creates a new (struct spwd) containing the + * information in the pointed-to (struct passwd). + */ +#define DAY (24L*3600L) +#define WEEK (7*DAY) +#define SCALE DAY +static struct spwd *pwd_to_spwd(const struct passwd *pw) +{ + static struct spwd sp; + + /* + * Nice, easy parts first. The name and passwd map directly + * from the old password structure to the new one. + */ + sp.sp_namp = pw->pw_name; + sp.sp_pwdp = pw->pw_passwd; + + /* + * Defaults used if there is no pw_age information. + */ + sp.sp_min = 0; + sp.sp_max = (10000L * DAY) / SCALE; + sp.sp_lstchg = time((time_t *) 0) / SCALE; + + /* + * These fields have no corresponding information in the password + * file. They are set to uninitialized values. + */ + sp.sp_warn = -1; + sp.sp_expire = -1; + sp.sp_inact = -1; + sp.sp_flag = -1; + + return &sp; +} + +/* putpwent(3) remix */ +static int adduser(const char *filename, struct passwd *p) +{ + FILE *passwd; + int r; + FILE *shadow; + struct spwd *sp; + + /* make sure everything is kosher and setup uid && gid */ + passwd = fopen_wrapper(filename, "a"); + if (passwd == NULL) { + /* return -1; */ + return 1; + } + fseek(passwd, 0, SEEK_END); + + /* if (passwd_study(filename, p) == 0) { */ + r = passwd_study(filename, p); + if (r) { + if (r == 1) + error_msg("%s: login already in use\n", p->pw_name); + else if (r == 2) + error_msg("illegal uid or no uids left\n"); + else if (r == 3) + error_msg("group name %s already in use\n", p->pw_name); + else + error_msg("generic error.\n"); + /* return -1; */ + return 1; + } + + /* add to passwd */ + if (putpwent(p, passwd) == -1) { + /* return -1; */ + return 1; + } + fclose(passwd); + + /* add to shadow if necessary */ + if (shadow_enabled) { + shadow = fopen_wrapper(SHADOW_FILE, "a"); + if (shadow == NULL) { + /* return -1; */ + return 1; + } + fseek(shadow, 0, SEEK_END); + sp = pwd_to_spwd(p); + sp->sp_max = 99999; /* debianish */ + sp->sp_warn = 7; + fprintf(shadow, "%s:!:%ld:%ld:%ld:%ld:::\n", + sp->sp_namp, sp->sp_lstchg, sp->sp_min, sp->sp_max, + sp->sp_warn); + fclose(shadow); + } + + /* add to group */ + /* addgroup should be responsible for dealing w/ gshadow */ + addgroup_wrapper(p->pw_name, p->pw_gid); + + /* Clear the umask for this process so it doesn't + * * screw up the permissions on the mkdir and chown. */ + umask(0); + + /* mkdir */ + if (mkdir(p->pw_dir, 0755)) { + perror_msg("%s", p->pw_dir); + } + /* Set the owner and group so it is owned by the new user. */ + if (chown(p->pw_dir, p->pw_uid, p->pw_gid)) { + perror_msg("%s", p->pw_dir); + } + /* Now fix up the permissions to 2755. Can't do it before now + * since chown will clear the setgid bit */ + if (chmod(p->pw_dir, 02755)) { + perror_msg("%s", p->pw_dir); + } + /* interactively set passwd */ + passwd_wrapper(p->pw_name); + + return 0; +} + + +/* return current uid (root is always uid == 0, right?) */ +static uid_t i_am_not_root() +{ + return geteuid(); +} + +/* + * 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) +{ + int i; + char opt; + char *login; + char *gecos; + char *home = NULL; + char *shell; + char path[MAXPATHLEN]; + + struct passwd pw; + + /* init */ + if (argc < 2) { + show_usage(); + } + gecos = default_gecos; + shell = default_shell; + + /* get args */ + for (i = 1; i < argc; i++) { + if (argv[i][0] == '-') { + opt = argv[i][1]; + switch (opt) { + case 'h': + home = argv[++i]; + break; + case 'g': + gecos = argv[++i]; + break; + case 's': + shell = argv[++i]; + break; + default: + error_msg("invalid option -- %c\n", opt); + break; + } + } else { + break; + } + } + + /* got root? */ + if (i_am_not_root()) { + error_msg_and_die( "Only root may add a user or group to the system.\n"); + } + + /* get login */ + if (i >= argc) { + error_msg_and_die( "adduser: no user specified\n"); + } + login = argv[i]; + + /* create string for $HOME if not specified already */ + if (!home) { + snprintf(path, MAXPATHLEN, "%s/%s", default_home_prefix, login); + path[MAXPATHLEN - 1] = 0; + home = path; + } + /* is /etc/shadow in use? */ + shadow_enabled = (0 == access(SHADOW_FILE, F_OK)); + + /* create a passwd struct */ + pw.pw_name = login; + pw.pw_passwd = default_passwd; + pw.pw_uid = 0; + pw.pw_gid = 0; + pw.pw_gecos = gecos; + pw.pw_dir = home; + pw.pw_shell = shell; + + /* grand finale */ + i = adduser(PASSWD_FILE, &pw); + + return (i); +} + +/* $Id: adduser.c,v 1.1 2001/08/21 16:18:59 andersen Exp $ */ |