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#if CONFIG_LAST_SYSTEM_ID < CONFIG_FIRST_SYSTEM_ID 13#error Bad LAST_SYSTEM_ID or FIRST_SYSTEM_ID in .config 14#endif 15 16/* #define OPT_HOME (1 << 0) */ /* unused */ 17/* #define OPT_GECOS (1 << 1) */ /* unused */ 18#define OPT_SHELL (1 << 2) 19#define OPT_GID (1 << 3) 20#define OPT_DONT_SET_PASS (1 << 4) 21#define OPT_SYSTEM_ACCOUNT (1 << 5) 22#define OPT_DONT_MAKE_HOME (1 << 6) 23#define OPT_UID (1 << 7) 24 25/* We assume UID_T_MAX == INT_MAX */ 26/* remix */ 27/* recoded such that the uid may be passed in *p */ 28static void passwd_study(struct passwd *p) 29{ 30 int max = UINT_MAX; 31 32 if (getpwnam(p->pw_name)) { 33 bb_error_msg_and_die("%s '%s' in use", "user", p->pw_name); 34 /* this format string is reused in adduser and addgroup */ 35 } 36 37 if (!(option_mask32 & OPT_UID)) { 38 if (option_mask32 & OPT_SYSTEM_ACCOUNT) { 39 p->pw_uid = CONFIG_FIRST_SYSTEM_ID; 40 max = CONFIG_LAST_SYSTEM_ID; 41 } else { 42 p->pw_uid = CONFIG_LAST_SYSTEM_ID + 1; 43 max = 64999; 44 } 45 } 46 /* check for a free uid (and maybe gid) */ 47 while (getpwuid(p->pw_uid) || (p->pw_gid == (gid_t)-1 && getgrgid(p->pw_uid))) { 48 if (option_mask32 & OPT_UID) { 49 /* -u N, cannot pick uid other than N: error */ 50 bb_error_msg_and_die("%s '%s' in use", "uid", itoa(p->pw_uid)); 51 /* this format string is reused in adduser and addgroup */ 52 } 53 if (p->pw_uid == max) { 54 bb_error_msg_and_die("no %cids left", 'u'); 55 } 56 p->pw_uid++; 57 } 58 59 if (p->pw_gid == (gid_t)-1) { 60 p->pw_gid = p->pw_uid; /* new gid = uid */ 61 if (getgrnam(p->pw_name)) { 62 bb_error_msg_and_die("%s '%s' in use", "group", p->pw_name); 63 /* this format string is reused in adduser and addgroup */ 64 } 65 } 66} 67 68static void addgroup_wrapper(struct passwd *p, const char *group_name) 69{ 70 char *cmd; 71 72 if (group_name) /* Add user to existing group */ 73 cmd = xasprintf("addgroup '%s' '%s'", p->pw_name, group_name); 74 else /* Add user to his own group with the first free gid found in passwd_study */ 75 cmd = xasprintf("addgroup -g %u '%s'", (unsigned)p->pw_gid, p->pw_name); 76 /* Warning: to be compatible with external addgroup programs we should use --gid instead */ 77 system(cmd); 78 free(cmd); 79} 80 81static void passwd_wrapper(const char *login) NORETURN; 82 83static void passwd_wrapper(const char *login) 84{ 85 BB_EXECLP("passwd", "passwd", login, NULL); 86 bb_error_msg_and_die("can't execute passwd, you must set password manually"); 87} 88 89#if ENABLE_FEATURE_ADDUSER_LONG_OPTIONS 90static const char adduser_longopts[] ALIGN1 = 91 "home\0" Required_argument "h" 92 "gecos\0" Required_argument "g" 93 "shell\0" Required_argument "s" 94 "ingroup\0" Required_argument "G" 95 "disabled-password\0" No_argument "D" 96 "empty-password\0" No_argument "D" 97 "system\0" No_argument "S" 98 "no-create-home\0" No_argument "H" 99 "uid\0" Required_argument "u" 100 ; 101#endif 102 103/* 104 * adduser will take a login_name as its first parameter. 105 * home, shell, gecos: 106 * can be customized via command-line parameters. 107 */ 108int adduser_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; 109int adduser_main(int argc UNUSED_PARAM, char **argv) 110{ 111 struct passwd pw; 112 const char *usegroup = NULL; 113 char *p; 114 unsigned opts; 115 116#if ENABLE_FEATURE_ADDUSER_LONG_OPTIONS 117 applet_long_options = adduser_longopts; 118#endif 119 120 /* got root? */ 121 if (geteuid()) { 122 bb_error_msg_and_die(bb_msg_perm_denied_are_you_root); 123 } 124 125 pw.pw_gecos = (char *)"Linux User,,,"; 126 pw.pw_shell = (char *)DEFAULT_SHELL; 127 pw.pw_dir = NULL; 128 129 /* exactly one non-option arg */ 130 /* disable interactive passwd for system accounts */ 131 opt_complementary = "=1:SD:u+"; 132 if (sizeof(pw.pw_uid) == sizeof(int)) { 133 opts = getopt32(argv, "h:g:s:G:DSHu:", &pw.pw_dir, &pw.pw_gecos, &pw.pw_shell, &usegroup, &pw.pw_uid); 134 } else { 135 unsigned uid; 136 opts = getopt32(argv, "h:g:s:G:DSHu:", &pw.pw_dir, &pw.pw_gecos, &pw.pw_shell, &usegroup, &uid); 137 if (opts & OPT_UID) { 138 pw.pw_uid = uid; 139 } 140 } 141 argv += optind; 142 143 /* fill in the passwd struct */ 144 pw.pw_name = argv[0]; 145 die_if_bad_username(pw.pw_name); 146 if (!pw.pw_dir) { 147 /* create string for $HOME if not specified already */ 148 pw.pw_dir = xasprintf("/home/%s", argv[0]); 149 } 150 pw.pw_passwd = (char *)"x"; 151 if (opts & OPT_SYSTEM_ACCOUNT) { 152 if (!usegroup) { 153 usegroup = "nogroup"; 154 } 155 if (!(opts & OPT_SHELL)) { 156 pw.pw_shell = (char *) "/bin/false"; 157 } 158 } 159 pw.pw_gid = usegroup ? xgroup2gid(usegroup) : -1; /* exits on failure */ 160 161 /* make sure everything is kosher and setup uid && maybe gid */ 162 passwd_study(&pw); 163 164 p = xasprintf("x:%u:%u:%s:%s:%s", 165 (unsigned) pw.pw_uid, (unsigned) pw.pw_gid, 166 pw.pw_gecos, pw.pw_dir, pw.pw_shell); 167 if (update_passwd(bb_path_passwd_file, pw.pw_name, p, NULL) < 0) { 168 return EXIT_FAILURE; 169 } 170 if (ENABLE_FEATURE_CLEAN_UP) 171 free(p); 172 173#if ENABLE_FEATURE_SHADOWPASSWDS 174 /* /etc/shadow fields: 175 * 1. username 176 * 2. encrypted password 177 * 3. last password change (unix date (unix time/24*60*60)) 178 * 4. minimum days required between password changes 179 * 5. maximum days password is valid 180 * 6. days before password is to expire that user is warned 181 * 7. days after password expires that account is disabled 182 * 8. unix date when login expires (i.e. when it may no longer be used) 183 */ 184 /* fields: 2 3 4 5 6 78 */ 185 p = xasprintf("!:%u:0:99999:7:::", (unsigned)(time(NULL)) / (24*60*60)); 186 /* ignore errors: if file is missing we suppose admin doesn't want it */ 187 update_passwd(bb_path_shadow_file, pw.pw_name, p, NULL); 188 if (ENABLE_FEATURE_CLEAN_UP) 189 free(p); 190#endif 191 192 /* add to group */ 193 addgroup_wrapper(&pw, usegroup); 194 195 /* clear the umask for this process so it doesn't 196 * screw up the permissions on the mkdir and chown. */ 197 umask(0); 198 if (!(opts & OPT_DONT_MAKE_HOME)) { 199 /* set the owner and group so it is owned by the new user, 200 * then fix up the permissions to 2755. Can't do it before 201 * since chown will clear the setgid bit */ 202 int mkdir_err = mkdir(pw.pw_dir, 0755); 203 if (mkdir_err == 0) { 204 /* New home. Copy /etc/skel to it */ 205 const char *args[] = { 206 "chown", "-R", 207 xasprintf("%u:%u", (int)pw.pw_uid, (int)pw.pw_gid), 208 pw.pw_dir, NULL 209 }; 210 /* Be silent on any errors (like: no /etc/skel) */ 211 logmode = LOGMODE_NONE; 212 copy_file("/etc/skel", pw.pw_dir, FILEUTILS_RECUR); 213 logmode = LOGMODE_STDIO; 214 chown_main(4, (char**)args); 215 } 216 if ((mkdir_err != 0 && errno != EEXIST) 217 || chown(pw.pw_dir, pw.pw_uid, pw.pw_gid) != 0 218 || chmod(pw.pw_dir, 02755) != 0 /* set setgid bit on homedir */ 219 ) { 220 bb_simple_perror_msg(pw.pw_dir); 221 } 222 } 223 224 if (!(opts & OPT_DONT_SET_PASS)) { 225 /* interactively set passwd */ 226 passwd_wrapper(pw.pw_name); 227 } 228 229 return EXIT_SUCCESS; 230} 231