static void
authenticate (const struct passwd* pw) {
const struct passwd* lpw = NULL;
const char* cp, *srvname = NULL;
int retval;
switch (su_mode) {
case SU_MODE:
srvname = simulate_login ? PAM_SRVNAME_SU_L : PAM_SRVNAME_SU;
break;
case RUNUSER_MODE:
srvname = simulate_login ? PAM_SRVNAME_RUNUSER_L : PAM_SRVNAME_RUNUSER;
break;
default:
abort();
break;
}
retval = pam_start (srvname, pw->pw_name, &conv, &pamh);
if (is_pam_failure(retval)) {
goto done;
}
if (isatty (0) && (cp = ttyname (0)) != NULL) {
const char* tty;
if (strncmp (cp, "/dev/", 5) == 0) {
tty = cp + 5;
} else {
tty = cp;
}
retval = pam_set_item (pamh, PAM_TTY, tty);
if (is_pam_failure(retval)) {
goto done;
}
}
lpw = current_getpwuid ();
if (lpw && lpw->pw_name) {
retval = pam_set_item (pamh, PAM_RUSER, (const void*) lpw->pw_name);
if (is_pam_failure(retval)) {
goto done;
}
}
if (su_mode == RUNUSER_MODE) {
/*
* This is the only difference between runuser(1) and su(1). The command
* runuser(1) does not required authentication, because user is root.
*/
if (restricted) {
errx(EXIT_FAILURE, _("may not be used by non-root users"));
}
return;
}
retval = pam_authenticate (pamh, 0);
if (is_pam_failure(retval)) {
goto done;
}
retval = pam_acct_mgmt (pamh, 0);
if (retval == PAM_NEW_AUTHTOK_REQD) {
/* Password has expired. Offer option to change it. */
retval = pam_chauthtok (pamh, PAM_CHANGE_EXPIRED_AUTHTOK);
}
done:
log_syslog(pw, !is_pam_failure(retval));
if (is_pam_failure(retval)) {
const char* msg;
log_btmp(pw);
msg = pam_strerror(pamh, retval);
pam_end(pamh, retval);
sleep (getlogindefs_num ("FAIL_DELAY", 1));
errx (EXIT_FAILURE, "%s", msg ? msg : _("incorrect password"));
}
}
static void loginpam_auth(struct login_context *cxt)
{
int rc, show_unknown;
unsigned int retries, failcount = 0;
const char *hostname = cxt->hostname ? cxt->hostname :
cxt->tty_name ? cxt->tty_name : "<unknown>";
pam_handle_t *pamh = cxt->pamh;
/* if we didn't get a user on the command line, set it to NULL */
loginpam_get_username(pamh, &cxt->username);
show_unknown = getlogindefs_bool("LOG_UNKFAIL_ENAB", 0);
retries = getlogindefs_num("LOGIN_RETRIES", LOGIN_MAX_TRIES);
/*
* There may be better ways to deal with some of these conditions, but
* at least this way I don't think we'll be giving away information...
*
* Perhaps someday we can trust that all PAM modules will pay attention
* to failure count and get rid of LOGIN_MAX_TRIES?
*/
rc = pam_authenticate(pamh, 0);
while ((++failcount < retries) &&
((rc == PAM_AUTH_ERR) ||
(rc == PAM_USER_UNKNOWN) ||
(rc == PAM_CRED_INSUFFICIENT) ||
(rc == PAM_AUTHINFO_UNAVAIL))) {
if (rc == PAM_USER_UNKNOWN && !show_unknown)
/*
* Logging unknown usernames may be a security issue if
* a user enters her password instead of her login name.
*/
cxt->username = NULL;
else
loginpam_get_username(pamh, &cxt->username);
syslog(LOG_NOTICE,
_("FAILED LOGIN %u FROM %s FOR %s, %s"),
failcount, hostname,
cxt->username ? cxt->username : "******",
pam_strerror(pamh, rc));
log_btmp(cxt);
log_audit(cxt, 0);
fprintf(stderr, _("Login incorrect\n\n"));
pam_set_item(pamh, PAM_USER, NULL);
rc = pam_authenticate(pamh, 0);
}
if (is_pam_failure(rc)) {
if (rc == PAM_USER_UNKNOWN && !show_unknown)
cxt->username = NULL;
else
loginpam_get_username(pamh, &cxt->username);
if (rc == PAM_MAXTRIES)
syslog(LOG_NOTICE,
_("TOO MANY LOGIN TRIES (%u) FROM %s FOR %s, %s"),
failcount, hostname,
cxt->username ? cxt->username : "******",
pam_strerror(pamh, rc));
else
syslog(LOG_NOTICE,
_("FAILED LOGIN SESSION FROM %s FOR %s, %s"),
hostname,
cxt->username ? cxt->username : "******",
pam_strerror(pamh, rc));
log_btmp(cxt);
log_audit(cxt, 0);
fprintf(stderr, _("\nLogin incorrect\n"));
pam_end(pamh, rc);
sleepexit(EXIT_SUCCESS);
}
}