release/src/router/busybox/loginutils/adduser.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * adduser - add users to /etc/passwd and /etc/shadow
   4  *
   5  * Copyright (C) 1999 by Lineo, inc. and John Beppu
   6  * Copyright (C) 1999,2000,2001 by John Beppu <beppu@codepoet.org>
   7  *
   8  * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
   9  */
  10 #include "libbb.h"
  11
  12 #define OPT_DONT_SET_PASS  (1 << 4)
  13 #define OPT_SYSTEM_ACCOUNT (1 << 5)
  14 #define OPT_DONT_MAKE_HOME (1 << 6)
  15
  16 /* remix */
  17 /* recoded such that the uid may be passed in *p */
  18 static void passwd_study(struct passwd *p)
  19 {
  20         int max;
  21
  22         if (getpwnam(p->pw_name))
  23                 bb_error_msg_and_die("login '%s' is in use", p->pw_name);
  24
  25         if (option_mask32 & OPT_SYSTEM_ACCOUNT) {
  26                 p->pw_uid = 0;
  27                 max = 999;
  28         } else {
  29                 p->pw_uid = 1000;
  30                 max = 64999;
  31         }
  32
  33         /* check for a free uid (and maybe gid) */
  34         while (getpwuid(p->pw_uid) || (p->pw_gid == (gid_t)-1 && getgrgid(p->pw_uid))) {
  35                 p->pw_uid++;
  36                 if (p->pw_uid > max)
  37                         bb_error_msg_and_die("no free uids left");
  38         }
  39
  40         if (p->pw_gid == (gid_t)-1) {
  41                 p->pw_gid = p->pw_uid; /* new gid = uid */
  42                 if (getgrnam(p->pw_name))
  43                         bb_error_msg_and_die("group name '%s' is in use", p->pw_name);
  44         }
  45 }
  46
  47 static void addgroup_wrapper(struct passwd *p)
  48 {
  49         char *cmd;
  50
  51         cmd = xasprintf("addgroup -g %u '%s'", (unsigned)p->pw_gid, p->pw_name);
  52         system(cmd);
  53         free(cmd);
  54 }
  55
  56 static void passwd_wrapper(const char *login) NORETURN;
  57
  58 static void passwd_wrapper(const char *login)
  59 {
  60         static const char prog[] ALIGN1 = "passwd";
  61
  62         BB_EXECLP(prog, prog, login, NULL);
  63         bb_error_msg_and_die("cannot execute %s, you must set password manually", prog);
  64 }
  65
  66 #if ENABLE_FEATURE_ADDUSER_LONG_OPTIONS
  67 static const char adduser_longopts[] ALIGN1 =
  68                 "home\0"                Required_argument "h"
  69                 "gecos\0"               Required_argument "g"
  70                 "shell\0"               Required_argument "s"
  71                 "ingroup\0"             Required_argument "G"
  72                 "disabled-password\0"   No_argument       "D"
  73                 "empty-password\0"      No_argument       "D"
  74                 "system\0"              No_argument       "S"
  75                 "no-create-home\0"      No_argument       "H"
  76                 ;
  77 #endif
  78
  79 /*
  80  * adduser will take a login_name as its first parameter.
  81  * home, shell, gecos:
  82  * can be customized via command-line parameters.
  83  */
  84 int adduser_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  85 int adduser_main(int argc UNUSED_PARAM, char **argv)
  86 {
  87         struct passwd pw;
  88         const char *usegroup = NULL;
  89         char *p;
  90
  91 #if ENABLE_FEATURE_ADDUSER_LONG_OPTIONS
  92         applet_long_options = adduser_longopts;
  93 #endif
  94
  95         /* got root? */
  96         if (geteuid()) {
  97                 bb_error_msg_and_die(bb_msg_perm_denied_are_you_root);
  98         }
  99
 100         pw.pw_gecos = (char *)"Linux User,,,";
 101         pw.pw_shell = (char *)DEFAULT_SHELL;
 102         pw.pw_dir = NULL;
 103
 104         /* exactly one non-option arg */
 105         opt_complementary = "=1";
 106         getopt32(argv, "h:g:s:G:DSH", &pw.pw_dir, &pw.pw_gecos, &pw.pw_shell, &usegroup);
 107         argv += optind;
 108
 109         /* fill in the passwd struct */
 110         pw.pw_name = argv[0];
 111         die_if_bad_username(pw.pw_name);
 112         if (!pw.pw_dir) {
 113                 /* create string for $HOME if not specified already */
 114                 pw.pw_dir = xasprintf("/home/%s", argv[0]);
 115         }
 116         pw.pw_passwd = (char *)"x";
 117         pw.pw_gid = usegroup ? xgroup2gid(usegroup) : -1; /* exits on failure */
 118
 119         /* make sure everything is kosher and setup uid && maybe gid */
 120         passwd_study(&pw);
 121
 122         p = xasprintf("x:%u:%u:%s:%s:%s", pw.pw_uid, pw.pw_gid, pw.pw_gecos, pw.pw_dir, pw.pw_shell);
 123         if (update_passwd(bb_path_passwd_file, pw.pw_name, p, NULL) < 0) {
 124                 return EXIT_FAILURE;
 125         }
 126         if (ENABLE_FEATURE_CLEAN_UP)
 127                 free(p);
 128
 129 #if ENABLE_FEATURE_SHADOWPASSWDS
 130         p = xasprintf("!:%u:0:99999:7:::", (unsigned)(time(NULL) / 86400)); /* sp->sp_lstchg */
 131         /* ignore errors: if file is missing we suppose admin doesn't want it */
 132         update_passwd(bb_path_shadow_file, pw.pw_name, p, NULL);
 133         if (ENABLE_FEATURE_CLEAN_UP)
 134                 free(p);
 135 #endif
 136
 137         /* add to group */
 138         /* addgroup should be responsible for dealing w/ gshadow */
 139         /* if using a pre-existing group, don't create one */
 140         if (!usegroup)
 141                 addgroup_wrapper(&pw);
 142
 143         /* clear the umask for this process so it doesn't
 144          * screw up the permissions on the mkdir and chown. */
 145         umask(0);
 146         if (!(option_mask32 & OPT_DONT_MAKE_HOME)) {
 147                 /* Set the owner and group so it is owned by the new user,
 148                    then fix up the permissions to 2755. Can't do it before
 149                    since chown will clear the setgid bit */
 150                 if (mkdir(pw.pw_dir, 0755)
 151                  || chown(pw.pw_dir, pw.pw_uid, pw.pw_gid)
 152                  || chmod(pw.pw_dir, 02755) /* set setgid bit on homedir */
 153                 ) {
 154                         bb_simple_perror_msg(pw.pw_dir);
 155                 }
 156         }
 157
 158         if (!(option_mask32 & OPT_DONT_SET_PASS)) {
 159                 /* interactively set passwd */
 160                 passwd_wrapper(pw.pw_name);
 161         }
 162
 163         return 0;
 164 }