freebsd-dev/lib/libpam/modules/pam_tacplus/pam_tacplus.c
John Polstra 9a10bb17e1 Build structure for contribified Linux-PAM, plus some home-grown
modules for FreeBSD's standard authentication methods.  Although
the Linux-PAM modules are present in the contrib tree, we don't
use any of them.

The main library "libpam" is composed of sources taken from three
places.  First are the standard Linux-PAM libpam sources from the
contrib tree.  Second are the Linux-PAM "libpam_misc" sources, also
from the contrib tree.  In Linux these form a separate library.
But as Mike Smith pointed out to me, that seems pointless, so I
have combined them into the libpam library.  Third are some additional
sources from the "src/lib/libpam" tree with some common functions
that make it easier to write modules.  Those I wrote myself.

This work has been donated to FreeBSD by Juniper Networks, Inc.
1998-11-18 01:44:37 +00:00

257 lines
7.0 KiB
C

/*-
* Copyright 1998 Juniper Networks, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <pwd.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <taclib.h>
#include <unistd.h>
#define PAM_SM_AUTH
#include <security/pam_modules.h>
#include "pam_mod_misc.h"
/* Option names, including the "=" sign. */
#define OPT_CONF "conf="
#define OPT_TMPL "template_user="
typedef int (*set_func)(struct tac_handle *, const char *);
static int do_item(pam_handle_t *, struct tac_handle *, int,
set_func, const char *);
static char *get_msg(struct tac_handle *);
static int set_msg(struct tac_handle *, const char *);
static int
do_item(pam_handle_t *pamh, struct tac_handle *tach, int item,
set_func func, const char *funcname)
{
int retval;
const void *value;
if ((retval = pam_get_item(pamh, item, &value)) != PAM_SUCCESS)
return retval;
if (value != NULL && (*func)(tach, (const char *)value) == -1) {
syslog(LOG_CRIT, "%s: %s", funcname, tac_strerror(tach));
tac_close(tach);
return PAM_SERVICE_ERR;
}
return PAM_SUCCESS;
}
static char *
get_msg(struct tac_handle *tach)
{
char *msg;
if ((msg = tac_get_msg(tach)) == NULL) {
syslog(LOG_CRIT, "tac_get_msg: %s", tac_strerror(tach));
tac_close(tach);
return NULL;
}
return msg;
}
static int
set_msg(struct tac_handle *tach, const char *msg)
{
if (tac_set_msg(tach, msg) == -1) {
syslog(LOG_CRIT, "tac_set_msg: %s", tac_strerror(tach));
tac_close(tach);
return -1;
}
return 0;
}
PAM_EXTERN int
pam_sm_authenticate(pam_handle_t *pamh, int flags, int argc,
const char **argv)
{
int retval;
struct tac_handle *tach;
const char *conf_file = NULL;
const char *template_user = NULL;
int options = 0;
int i;
for (i = 0; i < argc; i++) {
size_t len;
pam_std_option(&options, argv[i]);
if (strncmp(argv[i], OPT_CONF, (len = strlen(OPT_CONF))) == 0)
conf_file = argv[i] + len;
else if (strncmp(argv[i], OPT_TMPL,
(len = strlen(OPT_TMPL))) == 0)
template_user = argv[i] + len;
}
if ((tach = tac_open()) == NULL) {
syslog(LOG_CRIT, "tac_open failed");
return PAM_SERVICE_ERR;
}
if (tac_config(tach, conf_file) == -1) {
syslog(LOG_ALERT, "tac_config: %s", tac_strerror(tach));
tac_close(tach);
return PAM_SERVICE_ERR;
}
if (tac_create_authen(tach, TAC_AUTHEN_LOGIN, TAC_AUTHEN_TYPE_ASCII,
TAC_AUTHEN_SVC_LOGIN) == -1) {
syslog(LOG_CRIT, "tac_create_authen: %s", tac_strerror(tach));
tac_close(tach);
return PAM_SERVICE_ERR;
}
if ((retval = do_item(pamh, tach, PAM_USER,
tac_set_user, "tac_set_user")) != PAM_SUCCESS)
return retval;
if ((retval = do_item(pamh, tach, PAM_TTY,
tac_set_port, "tac_set_port")) != PAM_SUCCESS)
return retval;
if ((retval = do_item(pamh, tach, PAM_RHOST,
tac_set_rem_addr, "tac_set_rem_addr")) != PAM_SUCCESS)
return retval;
for ( ; ; ) {
char *srvr_msg;
size_t msg_len;
const char *user_msg;
char *data_msg;
int sflags;
int status;
int echo;
if ((sflags = tac_send_authen(tach)) == -1) {
syslog(LOG_CRIT, "tac_send_authen: %s",
tac_strerror(tach));
tac_close(tach);
return PAM_AUTHINFO_UNAVAIL;
}
status = TAC_AUTHEN_STATUS(sflags);
echo = TAC_AUTHEN_NOECHO(sflags) ? 0 : PAM_OPT_ECHO_PASS;
switch (status) {
case TAC_AUTHEN_STATUS_PASS:
tac_close(tach);
if (template_user != NULL) {
const void *item;
const char *user;
/*
* If the given user name doesn't exist in
* the local password database, change it
* to the value given in the "template_user"
* option.
*/
retval = pam_get_item(pamh, PAM_USER, &item);
if (retval != PAM_SUCCESS)
return retval;
user = (const char *)item;
if (getpwnam(user) == NULL)
pam_set_item(pamh, PAM_USER,
template_user);
}
return PAM_SUCCESS;
case TAC_AUTHEN_STATUS_FAIL:
tac_close(tach);
return PAM_AUTH_ERR;
case TAC_AUTHEN_STATUS_GETUSER:
case TAC_AUTHEN_STATUS_GETPASS:
if ((srvr_msg = get_msg(tach)) == NULL)
return PAM_SERVICE_ERR;
if (status == TAC_AUTHEN_STATUS_GETUSER)
retval = pam_get_user(pamh, &user_msg,
srvr_msg[0] != '\0' ? srvr_msg : NULL);
else if (status == TAC_AUTHEN_STATUS_GETPASS)
retval = pam_get_pass(pamh, &user_msg,
srvr_msg[0] != '\0' ? srvr_msg :
"Password:", options | echo);
free(srvr_msg);
if (retval != PAM_SUCCESS) {
/* XXX - send a TACACS+ abort packet */
tac_close(tach);
return retval;
}
if (set_msg(tach, user_msg) == -1)
return PAM_SERVICE_ERR;
break;
case TAC_AUTHEN_STATUS_GETDATA:
if ((srvr_msg = get_msg(tach)) == NULL)
return PAM_SERVICE_ERR;
retval = pam_prompt(pamh,
(options|echo) & PAM_OPT_ECHO_PASS ?
PAM_PROMPT_ECHO_ON : PAM_PROMPT_ECHO_OFF,
srvr_msg[0] != '\0' ? srvr_msg : "Data:",
&data_msg);
free(srvr_msg);
if (retval != PAM_SUCCESS) {
/* XXX - send a TACACS+ abort packet */
tac_close(tach);
return retval;
}
retval = set_msg(tach, data_msg);
memset(data_msg, 0, strlen(data_msg));
free(data_msg);
if (retval == -1)
return PAM_SERVICE_ERR;
break;
case TAC_AUTHEN_STATUS_ERROR:
srvr_msg = (char *)tac_get_data(tach, &msg_len);
if (srvr_msg != NULL && msg_len != 0) {
syslog(LOG_CRIT, "tac_send_authen:"
" server detected error: %s", srvr_msg);
free(srvr_msg);
} else
syslog(LOG_CRIT,
"tac_send_authen: server detected error");
tac_close(tach);
return PAM_AUTHINFO_UNAVAIL;
break;
case TAC_AUTHEN_STATUS_RESTART:
case TAC_AUTHEN_STATUS_FOLLOW:
default:
syslog(LOG_CRIT,
"tac_send_authen: unexpected status %#x", status);
tac_close(tach);
return PAM_AUTHINFO_UNAVAIL;
}
}
}
PAM_EXTERN int
pam_sm_setcred(pam_handle_t *pamh, int flags, int argc, const char **argv)
{
return PAM_SUCCESS;
}