| /* vi: set sw=4 ts=4: */ |
| /* |
| * Licensed under GPLv2 or later, see file LICENSE in this source tree. |
| */ |
| |
| //usage:#define passwd_trivial_usage |
| //usage: "[OPTIONS] [USER]" |
| //usage:#define passwd_full_usage "\n\n" |
| //usage: "Change USER's password (default: current user)" |
| //usage: "\n" |
| //usage: "\n -a ALG Encryption method" |
| //usage: "\n -d Set password to ''" |
| //usage: "\n -l Lock (disable) account" |
| //usage: "\n -u Unlock (enable) account" |
| |
| #include "libbb.h" |
| #include <syslog.h> |
| |
| static void nuke_str(char *str) |
| { |
| if (str) memset(str, 0, strlen(str)); |
| } |
| |
| static char* new_password(const struct passwd *pw, uid_t myuid, const char *algo) |
| { |
| char salt[MAX_PW_SALT_LEN]; |
| char *orig = (char*)""; |
| char *newp = NULL; |
| char *cp = NULL; |
| char *ret = NULL; /* failure so far */ |
| |
| if (myuid != 0 && pw->pw_passwd[0]) { |
| char *encrypted; |
| |
| orig = bb_ask_stdin("Old password: "); /* returns ptr to static */ |
| if (!orig) |
| goto err_ret; |
| encrypted = pw_encrypt(orig, pw->pw_passwd, 1); /* returns malloced str */ |
| if (strcmp(encrypted, pw->pw_passwd) != 0) { |
| syslog(LOG_WARNING, "incorrect password for %s", pw->pw_name); |
| bb_do_delay(LOGIN_FAIL_DELAY); |
| puts("Incorrect password"); |
| goto err_ret; |
| } |
| if (ENABLE_FEATURE_CLEAN_UP) |
| free(encrypted); |
| } |
| orig = xstrdup(orig); /* or else bb_ask_stdin() will destroy it */ |
| newp = bb_ask_stdin("New password: "); /* returns ptr to static */ |
| if (!newp) |
| goto err_ret; |
| newp = xstrdup(newp); /* we are going to bb_ask_stdin() again, so save it */ |
| if (ENABLE_FEATURE_PASSWD_WEAK_CHECK |
| && obscure(orig, newp, pw) |
| && myuid != 0 |
| ) { |
| goto err_ret; /* non-root is not allowed to have weak passwd */ |
| } |
| |
| cp = bb_ask_stdin("Retype password: "); |
| if (!cp) |
| goto err_ret; |
| if (strcmp(cp, newp) != 0) { |
| puts("Passwords don't match"); |
| goto err_ret; |
| } |
| |
| crypt_make_pw_salt(salt, algo); |
| |
| /* pw_encrypt returns malloced str */ |
| ret = pw_encrypt(newp, salt, 1); |
| /* whee, success! */ |
| |
| err_ret: |
| nuke_str(orig); |
| if (ENABLE_FEATURE_CLEAN_UP) free(orig); |
| |
| nuke_str(newp); |
| if (ENABLE_FEATURE_CLEAN_UP) free(newp); |
| |
| nuke_str(cp); |
| return ret; |
| } |
| |
| int passwd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
| int passwd_main(int argc UNUSED_PARAM, char **argv) |
| { |
| enum { |
| OPT_algo = (1 << 0), /* -a - password algorithm */ |
| OPT_lock = (1 << 1), /* -l - lock account */ |
| OPT_unlock = (1 << 2), /* -u - unlock account */ |
| OPT_delete = (1 << 3), /* -d - delete password */ |
| OPT_lud = OPT_lock | OPT_unlock | OPT_delete, |
| }; |
| unsigned opt; |
| int rc; |
| const char *opt_a = CONFIG_FEATURE_DEFAULT_PASSWD_ALGO; |
| const char *filename; |
| char *myname; |
| char *name; |
| char *newp; |
| struct passwd *pw; |
| uid_t myuid; |
| struct rlimit rlimit_fsize; |
| char c; |
| #if ENABLE_FEATURE_SHADOWPASSWDS |
| /* Using _r function to avoid pulling in static buffers */ |
| struct spwd spw; |
| char buffer[256]; |
| #endif |
| |
| logmode = LOGMODE_BOTH; |
| openlog(applet_name, 0, LOG_AUTH); |
| opt = getopt32(argv, "a:lud", &opt_a); |
| //argc -= optind; |
| argv += optind; |
| |
| myuid = getuid(); |
| /* -l, -u, -d require root priv and username argument */ |
| if ((opt & OPT_lud) && (myuid != 0 || !argv[0])) |
| bb_show_usage(); |
| |
| /* Will complain and die if username not found */ |
| myname = xstrdup(xuid2uname(myuid)); |
| name = argv[0] ? argv[0] : myname; |
| |
| pw = xgetpwnam(name); |
| if (myuid != 0 && pw->pw_uid != myuid) { |
| /* LOGMODE_BOTH */ |
| bb_error_msg_and_die("%s can't change password for %s", myname, name); |
| } |
| |
| #if ENABLE_FEATURE_SHADOWPASSWDS |
| { |
| /* getspnam_r may return 0 yet set result to NULL. |
| * At least glibc 2.4 does this. Be extra paranoid here. */ |
| struct spwd *result = NULL; |
| errno = 0; |
| if (getspnam_r(pw->pw_name, &spw, buffer, sizeof(buffer), &result) != 0 |
| || !result /* no error, but no record found either */ |
| || strcmp(result->sp_namp, pw->pw_name) != 0 /* paranoia */ |
| ) { |
| if (errno != ENOENT) { |
| /* LOGMODE_BOTH */ |
| bb_perror_msg("no record of %s in %s, using %s", |
| name, bb_path_shadow_file, |
| bb_path_passwd_file); |
| } |
| /* else: /etc/shadow does not exist, |
| * apparently we are on a shadow-less system, |
| * no surprise there */ |
| } else { |
| pw->pw_passwd = result->sp_pwdp; |
| } |
| } |
| #endif |
| |
| /* Decide what the new password will be */ |
| newp = NULL; |
| c = pw->pw_passwd[0] - '!'; |
| if (!(opt & OPT_lud)) { |
| if (myuid != 0 && !c) { /* passwd starts with '!' */ |
| /* LOGMODE_BOTH */ |
| bb_error_msg_and_die("can't change " |
| "locked password for %s", name); |
| } |
| printf("Changing password for %s\n", name); |
| newp = new_password(pw, myuid, opt_a); |
| if (!newp) { |
| logmode = LOGMODE_STDIO; |
| bb_error_msg_and_die("password for %s is unchanged", name); |
| } |
| } else if (opt & OPT_lock) { |
| if (!c) |
| goto skip; /* passwd starts with '!' */ |
| newp = xasprintf("!%s", pw->pw_passwd); |
| } else if (opt & OPT_unlock) { |
| if (c) |
| goto skip; /* not '!' */ |
| /* pw->pw_passwd points to static storage, |
| * strdup'ing to avoid nasty surprizes */ |
| newp = xstrdup(&pw->pw_passwd[1]); |
| } else if (opt & OPT_delete) { |
| newp = (char*)""; |
| } |
| |
| rlimit_fsize.rlim_cur = rlimit_fsize.rlim_max = 512L * 30000; |
| setrlimit(RLIMIT_FSIZE, &rlimit_fsize); |
| bb_signals(0 |
| + (1 << SIGHUP) |
| + (1 << SIGINT) |
| + (1 << SIGQUIT) |
| , SIG_IGN); |
| umask(077); |
| xsetuid(0); |
| |
| #if ENABLE_FEATURE_SHADOWPASSWDS |
| filename = bb_path_shadow_file; |
| rc = update_passwd(bb_path_shadow_file, name, newp, NULL); |
| if (rc > 0) |
| /* password in /etc/shadow was updated */ |
| newp = (char*) "x"; |
| if (rc >= 0) |
| /* 0 = /etc/shadow missing (not an error), >0 = passwd changed in /etc/shadow */ |
| #endif |
| { |
| filename = bb_path_passwd_file; |
| rc = update_passwd(bb_path_passwd_file, name, newp, NULL); |
| } |
| /* LOGMODE_BOTH */ |
| if (rc < 0) |
| bb_error_msg_and_die("can't update password file %s", filename); |
| bb_info_msg("Password for %s changed by %s", name, myname); |
| |
| /*if (ENABLE_FEATURE_CLEAN_UP) free(newp); - can't, it may be non-malloced */ |
| skip: |
| if (!newp) { |
| bb_error_msg_and_die("password for %s is already %slocked", |
| name, (opt & OPT_unlock) ? "un" : ""); |
| } |
| |
| if (ENABLE_FEATURE_CLEAN_UP) |
| free(myname); |
| return 0; |
| } |