1 /* vi: set sw=4 ts=4: */
3 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
6 //usage:#define passwd_trivial_usage
7 //usage: "[OPTIONS] [USER]"
8 //usage:#define passwd_full_usage "\n\n"
9 //usage: "Change USER's password (default: current user)"
11 //usage: "\n -a ALG Encryption method"
12 //usage: "\n -d Set password to ''"
13 //usage: "\n -l Lock (disable) account"
14 //usage: "\n -u Unlock (enable) account"
18 #include <sys/resource.h> /* setrlimit */
20 static char* new_password(const struct passwd *pw, uid_t myuid, const char *algo)
22 char salt[MAX_PW_SALT_LEN];
23 char *orig = (char*)"";
26 char *ret = NULL; /* failure so far */
28 if (myuid != 0 && pw->pw_passwd[0]) {
31 orig = bb_ask_stdin("Old password: "); /* returns ptr to static */
34 encrypted = pw_encrypt(orig, pw->pw_passwd, 1); /* returns malloced str */
35 if (strcmp(encrypted, pw->pw_passwd) != 0) {
36 syslog(LOG_WARNING, "incorrect password for %s", pw->pw_name);
37 bb_do_delay(LOGIN_FAIL_DELAY);
38 puts("Incorrect password");
41 if (ENABLE_FEATURE_CLEAN_UP)
44 orig = xstrdup(orig); /* or else bb_ask_stdin() will destroy it */
45 newp = bb_ask_stdin("New password: "); /* returns ptr to static */
48 newp = xstrdup(newp); /* we are going to bb_ask_stdin() again, so save it */
49 if (ENABLE_FEATURE_PASSWD_WEAK_CHECK
50 && obscure(orig, newp, pw)
53 goto err_ret; /* non-root is not allowed to have weak passwd */
56 cp = bb_ask_stdin("Retype password: ");
59 if (strcmp(cp, newp) != 0) {
60 puts("Passwords don't match");
64 crypt_make_pw_salt(salt, algo);
66 /* pw_encrypt returns malloced str */
67 ret = pw_encrypt(newp, salt, 1);
72 if (ENABLE_FEATURE_CLEAN_UP) free(orig);
75 if (ENABLE_FEATURE_CLEAN_UP) free(newp);
81 int passwd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
82 int passwd_main(int argc UNUSED_PARAM, char **argv)
85 OPT_algo = (1 << 0), /* -a - password algorithm */
86 OPT_lock = (1 << 1), /* -l - lock account */
87 OPT_unlock = (1 << 2), /* -u - unlock account */
88 OPT_delete = (1 << 3), /* -d - delete password */
89 OPT_lud = OPT_lock | OPT_unlock | OPT_delete,
93 const char *opt_a = CONFIG_FEATURE_DEFAULT_PASSWD_ALGO;
100 struct rlimit rlimit_fsize;
102 #if ENABLE_FEATURE_SHADOWPASSWDS
103 /* Using _r function to avoid pulling in static buffers */
108 logmode = LOGMODE_BOTH;
109 openlog(applet_name, 0, LOG_AUTH);
110 opt = getopt32(argv, "a:lud", &opt_a);
115 /* -l, -u, -d require root priv and username argument */
116 if ((opt & OPT_lud) && (myuid != 0 || !argv[0]))
119 /* Will complain and die if username not found */
120 myname = xstrdup(xuid2uname(myuid));
121 name = argv[0] ? argv[0] : myname;
123 pw = xgetpwnam(name);
124 if (myuid != 0 && pw->pw_uid != myuid) {
126 bb_error_msg_and_die("%s can't change password for %s", myname, name);
129 #if ENABLE_FEATURE_SHADOWPASSWDS
131 /* getspnam_r may return 0 yet set result to NULL.
132 * At least glibc 2.4 does this. Be extra paranoid here. */
133 struct spwd *result = NULL;
135 if (getspnam_r(pw->pw_name, &spw, buffer, sizeof(buffer), &result) != 0
136 || !result /* no error, but no record found either */
137 || strcmp(result->sp_namp, pw->pw_name) != 0 /* paranoia */
139 if (errno != ENOENT) {
141 bb_perror_msg("no record of %s in %s, using %s",
142 name, bb_path_shadow_file,
143 bb_path_passwd_file);
145 /* else: /etc/shadow does not exist,
146 * apparently we are on a shadow-less system,
147 * no surprise there */
149 pw->pw_passwd = result->sp_pwdp;
154 /* Decide what the new password will be */
156 c = pw->pw_passwd[0] - '!';
157 if (!(opt & OPT_lud)) {
158 if (myuid != 0 && !c) { /* passwd starts with '!' */
160 bb_error_msg_and_die("can't change "
161 "locked password for %s", name);
163 printf("Changing password for %s\n", name);
164 newp = new_password(pw, myuid, opt_a);
166 logmode = LOGMODE_STDIO;
167 bb_error_msg_and_die("password for %s is unchanged", name);
169 } else if (opt & OPT_lock) {
171 goto skip; /* passwd starts with '!' */
172 newp = xasprintf("!%s", pw->pw_passwd);
173 } else if (opt & OPT_unlock) {
175 goto skip; /* not '!' */
176 /* pw->pw_passwd points to static storage,
177 * strdup'ing to avoid nasty surprizes */
178 newp = xstrdup(&pw->pw_passwd[1]);
179 } else if (opt & OPT_delete) {
183 rlimit_fsize.rlim_cur = rlimit_fsize.rlim_max = 512L * 30000;
184 setrlimit(RLIMIT_FSIZE, &rlimit_fsize);
193 #if ENABLE_FEATURE_SHADOWPASSWDS
194 filename = bb_path_shadow_file;
195 rc = update_passwd(bb_path_shadow_file, name, newp, NULL);
197 /* password in /etc/shadow was updated */
200 /* 0 = /etc/shadow missing (not an error), >0 = passwd changed in /etc/shadow */
203 filename = bb_path_passwd_file;
204 rc = update_passwd(bb_path_passwd_file, name, newp, NULL);
208 bb_error_msg_and_die("can't update password file %s", filename);
209 bb_info_msg("Password for %s changed by %s", name, myname);
211 /*if (ENABLE_FEATURE_CLEAN_UP) free(newp); - can't, it may be non-malloced */
214 bb_error_msg_and_die("password for %s is already %slocked",
215 name, (opt & OPT_unlock) ? "un" : "");
218 if (ENABLE_FEATURE_CLEAN_UP)