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pam_tacplus.c
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pam_tacplus.c
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/* pam_tacplus.c - PAM interface for TACACS+ protocol.
*
* Copyright (C) 2010, Pawel Krawczyk <pawel.krawczyk@hush.com> and
* Jeroen Nijhof <jeroen@jeroennijhof.nl>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program - see the file COPYING.
*
* See `CHANGES' file for revision history.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdlib.h> /* malloc */
#include <stdio.h>
#include <syslog.h>
#include <netdb.h> /* gethostbyname */
#include <sys/socket.h> /* in_addr */
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdarg.h> /* va_ */
#include <signal.h>
#include <string.h> /* strdup */
#include <ctype.h>
#include <time.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include "libtac.h"
#include "pam_tacplus.h"
#include "support.h"
/* address of server discovered by pam_sm_authenticate */
static tacplus_server_t active_server;
struct addrinfo active_addrinfo;
struct sockaddr active_sockaddr;
struct sockaddr_in6 active_sockaddr6;
char active_key[TAC_SECRET_MAX_LEN + 1];
/* copy a server's information into active_server */
static void set_active_server(const tacplus_server_t *tac_svr)
{
active_addrinfo.ai_addr = &active_sockaddr;
memset(&active_server, 0, sizeof(tacplus_server_t));
memset(&active_addrinfo, 0, sizeof(struct addrinfo));
memset(&active_sockaddr, 0, sizeof(struct sockaddr));
memset(&active_sockaddr6, 0, sizeof(struct sockaddr_in6));
if (tac_svr->addr == NULL)
{
_pam_log(LOG_ERR, "internal error: null values passed to set_active_server()");
return;
}
if (tac_svr->addr->ai_family == AF_INET6)
{
active_addrinfo.ai_addr = (struct sockaddr *)&active_sockaddr6;
}
else
{
active_addrinfo.ai_addr = &active_sockaddr;
}
tac_copy_addr_info(&active_addrinfo, tac_svr->addr);
strncpy(active_key, tac_svr->key ? tac_svr->key : "", TAC_SECRET_MAX_LEN - 1);
active_server.addr = &active_addrinfo;
syslog(LOG_DEBUG, "%s: active server set as [%s]", __FUNCTION__,
tac_ntop(active_server.addr->ai_addr));
active_server.key = active_key;
}
/* Helper functions */
int _pam_send_account(int tac_fd, int type, const char *user, char *tty,
char *r_addr, char *cmd) {
char buf[64];
int retval;
time_t t;
struct tm tm;
gl_list_t send_attr;
send_attr = gl_list_create_empty(GL_ARRAY_LIST, NULL, NULL, NULL, false);
t = time(NULL);
gmtime_r(&t, &tm);
strftime(buf, sizeof(buf), "%s", &tm);
if (type == TAC_PLUS_ACCT_FLAG_START) {
tac_add_attrib(send_attr, "start_time", buf);
} else if (type == TAC_PLUS_ACCT_FLAG_STOP)
{
tac_add_attrib(send_attr, "stop_time", buf);
}
snprintf(buf, sizeof(buf), "%d", getpid());
tac_add_attrib(send_attr, "task_id", buf);
tac_add_attrib(send_attr, "service", tac_service);
if (tac_protocol[0] != '\0')
tac_add_attrib(send_attr, "protocol", tac_protocol);
if (cmd != NULL)
{
tac_add_attrib(send_attr, "cmd", cmd);
}
retval = tac_acct_send(tac_fd, type, user, tty, r_addr, send_attr);
/* this is no longer needed */
tac_free_attrib(send_attr);
if (retval < 0) {
_pam_log(LOG_WARNING, "%s: send %s accounting failed (task %d)",
__FUNCTION__, tac_acct_flag2str(type), getpid());
close(tac_fd);
return -1;
}
struct areply re;
memset(&re, 0, sizeof(re));
re.attr = gl_list_create_empty(GL_ARRAY_LIST, NULL, NULL, NULL, false);
retval = tac_acct_read(tac_fd, &re);
close(tac_fd);
if (retval != TAC_PLUS_ACCT_STATUS_SUCCESS) {
_pam_log(LOG_WARNING, "%s: accounting %s failed (task %d)",
__FUNCTION__, tac_acct_flag2str(type), getpid());
if (re.msg != NULL)
free(re.msg);
tac_free_attrib(re.attr);
return -1;
}
if (re.msg != NULL)
free(re.msg);
tac_free_attrib(re.attr);
return 0;
}
int _pam_account(pam_handle_t *pamh, int argc, const char **argv, int type,
char *cmd)
{
int retval;
static int ctrl;
char *user = NULL;
char *tty = NULL;
char *r_addr = NULL;
char *typemsg;
int status = PAM_SESSION_ERR;
int tac_fd;
unsigned long srv_i;
typemsg = tac_acct_flag2str(type);
ctrl = _pam_parse(argc, argv);
if (ctrl & PAM_TAC_DEBUG) {
syslog(LOG_DEBUG, "%s: [%s] called (%s)",
__FUNCTION__, typemsg, PACKAGE_STRING);
syslog(LOG_DEBUG, "%s: tac_srv_no=%d", __FUNCTION__, tac_srv_no);
}
if ((user = _pam_get_user(pamh)) == NULL)
return PAM_USER_UNKNOWN;
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: username [%s] obtained", __FUNCTION__, user);
tty = _pam_get_terminal(pamh);
if (!strncmp(tty, "/dev/", 5))
tty += 5;
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: tty [%s] obtained", __FUNCTION__, tty);
r_addr = _pam_get_rhost(pamh);
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: rhost [%s] obtained", __FUNCTION__, r_addr);
/* checks for specific data required by TACACS+, which should
be supplied in command line */
if (*tac_service == '\0')
{
_pam_log(LOG_ERR, "ACC: TACACS+ service type not configured");
return PAM_AUTH_ERR;
}
if (*tac_protocol == '\0')
{
_pam_log(LOG_ERR,
"ACC: TACACS+ protocol type not configured (IGNORED)");
}
/* when this module is called from within pppd or other
application dealing with serial lines, it is likely
that we will get hit with signal caused by modem hangup;
this is important only for STOP packets, it's relatively
rare that modem hangs up on accounting start */
if (type == TAC_PLUS_ACCT_FLAG_STOP)
{
signal(SIGALRM, SIG_IGN);
signal(SIGCHLD, SIG_IGN);
signal(SIGHUP, SIG_IGN);
}
status = PAM_SESSION_ERR;
for (srv_i = 0; srv_i < tac_srv_no; srv_i++)
{
tac_fd = tac_connect_single(tac_srv[srv_i].addr, tac_srv[srv_i].key,
NULL, tac_timeout);
if (tac_fd < 0)
{
_pam_log(LOG_WARNING, "%s: error sending %s (fd)", __FUNCTION__,
typemsg);
continue;
}
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: connected with fd=%d (srv %lu)", __FUNCTION__,
tac_fd, srv_i);
retval = _pam_send_account(tac_fd, type, user, tty, r_addr, cmd);
if (retval < 0)
{
_pam_log(LOG_WARNING, "%s: error sending %s (acct)", __FUNCTION__,
typemsg);
}
else
{
status = PAM_SUCCESS;
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: [%s] for [%s] sent", __FUNCTION__,
typemsg, user);
}
close(tac_fd);
if ((status == PAM_SUCCESS) && !(ctrl & PAM_TAC_ACCT))
{
/* do not send acct start/stop packets to _all_ servers */
break;
}
}
if (type == TAC_PLUS_ACCT_FLAG_STOP)
{
signal(SIGALRM, SIG_DFL);
signal(SIGCHLD, SIG_DFL);
signal(SIGHUP, SIG_DFL);
}
return status;
}
/* Main PAM functions */
/* authenticates user on remote TACACS+ server
* returns PAM_SUCCESS if the supplied username and password
* pair is valid
*/
PAM_EXTERN
int pam_sm_authenticate(pam_handle_t *pamh, int flags, int argc,
const char **argv)
{
int ctrl, retval;
char *user;
char *pass;
char *tty;
char *r_addr;
unsigned long srv_i;
int tac_fd, status, tac_status, communicating;
user = pass = tty = r_addr = NULL;
ctrl = _pam_parse(argc, argv);
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: called (%s)", __FUNCTION__, PACKAGE_STRING);
if ((user = _pam_get_user(pamh)) == NULL)
return PAM_USER_UNKNOWN;
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: user [%s] obtained", __FUNCTION__, user);
retval = tacacs_get_password(pamh, flags, ctrl, &pass);
if (retval != PAM_SUCCESS || pass == NULL || *pass == '\0')
{
_pam_log(LOG_ERR, "unable to obtain password");
free(pass);
return PAM_CRED_INSUFFICIENT;
}
retval = pam_set_item(pamh, PAM_AUTHTOK, pass);
if (retval != PAM_SUCCESS) {
_pam_log(LOG_ERR, "unable to set password");
free(pass);
return PAM_CRED_INSUFFICIENT;
}
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: password obtained", __FUNCTION__);
tty = _pam_get_terminal(pamh);
if (!strncmp(tty, "/dev/", strlen("/dev/")))
tty += strlen("/dev/");
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: tty [%s] obtained", __FUNCTION__, tty);
r_addr = _pam_get_rhost(pamh);
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: rhost [%s] obtained", __FUNCTION__, r_addr);
status = PAM_AUTHINFO_UNAVAIL;
for (srv_i = 0; srv_i < tac_srv_no; srv_i++) {
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: trying srv %lu", __FUNCTION__, srv_i);
tac_fd = tac_connect_single(tac_srv[srv_i].addr, tac_srv[srv_i].key,
NULL, tac_timeout);
if (tac_fd < 0) {
_pam_log(LOG_ERR, "connection failed srv %lu: %m", srv_i);
active_server.addr = NULL;
continue;
}
if (tac_authen_send(tac_fd, user, pass, tty, r_addr, TAC_PLUS_AUTHEN_LOGIN) < 0) {
close(tac_fd);
_pam_log(LOG_ERR, "error sending auth req to TACACS+ server");
active_server.addr = NULL;
continue;
}
communicating = 1;
while (communicating) {
struct pam_message conv_msg;
struct pam_response *resp = NULL;
memset(&conv_msg, 0, sizeof(conv_msg));
struct areply arep;
memset(&arep, 0, sizeof(arep));
arep.attr = gl_list_create_empty(GL_ARRAY_LIST, NULL, NULL, NULL, false);
tac_status = tac_authen_read(tac_fd, &arep);
if (arep.msg != NULL) {
conv_msg.msg = arep.msg;
}
/* talk the protocol */
switch (tac_status) {
case TAC_PLUS_AUTHEN_STATUS_PASS:
/* success */
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG,
"tacacs status: TAC_PLUS_AUTHEN_STATUS_PASS");
if (conv_msg.msg != NULL) {
conv_msg.msg_style = PAM_TEXT_INFO;
retval = converse(pamh, 1, &conv_msg, &resp);
if (PAM_SUCCESS == retval) {
if (PAM_TAC_DEBUG == (ctrl & PAM_TAC_DEBUG))
syslog(LOG_DEBUG, "send tac_status=\"%s\"", conv_msg.msg);
} else {
_pam_log(LOG_WARNING,
"%s: error sending tac_status=\"%s\", retval=%d",
__FUNCTION__, conv_msg.msg, retval);
}
}
status = PAM_SUCCESS;
communicating = 0;
set_active_server(&tac_srv[srv_i]);
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: active srv %lu", __FUNCTION__, srv_i);
break;
case TAC_PLUS_AUTHEN_STATUS_FAIL:
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG,
"tacacs status: TAC_PLUS_AUTHEN_STATUS_FAIL");
if (conv_msg.msg != NULL) {
conv_msg.msg_style = PAM_ERROR_MSG;
retval = converse(pamh, 1, &conv_msg, &resp);
if (PAM_SUCCESS == retval) {
if (PAM_TAC_DEBUG == (ctrl & PAM_TAC_DEBUG))
syslog(LOG_DEBUG, "send tac_status=\"%s\"", conv_msg.msg);
} else {
_pam_log(LOG_WARNING,
"%s: error sending tac_status=\"%s\", retval=%d",
__FUNCTION__, conv_msg.msg, retval);
}
}
status = PAM_AUTH_ERR;
communicating = 0;
_pam_log(LOG_ERR, "auth failed: %d", tac_status);
break;
case TAC_PLUS_AUTHEN_STATUS_GETDATA:
if (PAM_TAC_DEBUG == (ctrl & PAM_TAC_DEBUG))
syslog(LOG_DEBUG,
"tacacs status: TAC_PLUS_AUTHEN_STATUS_GETDATA");
if (conv_msg.msg != NULL) {
int echo_off = (0x1 == (arep.flags & 0x1));
conv_msg.msg_style =
echo_off ? PAM_PROMPT_ECHO_OFF : PAM_PROMPT_ECHO_ON;
retval = converse(pamh, 1, &conv_msg, &resp);
if (PAM_SUCCESS == retval) {
if (PAM_TAC_DEBUG == (ctrl & PAM_TAC_DEBUG))
syslog(LOG_DEBUG, "sent tac_status=\"%s\", resp=\"%s\"",
conv_msg.msg, resp->resp);
if (PAM_TAC_DEBUG == (ctrl & PAM_TAC_DEBUG))
syslog(LOG_DEBUG, "%s: calling tac_cont_send",
__FUNCTION__);
if (0 > tac_cont_send_seq(tac_fd, resp->resp,
arep.seq_no + 1)) {
_pam_log(LOG_ERR,
"error sending continue req to TACACS+ server");
status = PAM_AUTH_ERR;
communicating = 0;
}
}
else
{
_pam_log(LOG_WARNING,
"%s: error sending tac_status=\"%s\", retval=%d (%s)",
__FUNCTION__, conv_msg.msg, retval,
pam_strerror(pamh, retval));
status = PAM_AUTH_ERR;
communicating = 0;
}
}
else
{
syslog(LOG_ERR,
"GETDATA response with no message, returning PAM_AUTH_ERR");
status = PAM_AUTH_ERR;
communicating = 0;
}
break;
case TAC_PLUS_AUTHEN_STATUS_GETUSER:
/* not implemented */
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG,
"tacacs status: TAC_PLUS_AUTHEN_STATUS_GETUSER");
syslog(LOG_ERR, "%s: TAC_PLUS_AUTHEN_STATUS_GETUSER not implemented", __FUNCTION__);
abort();
communicating = 0;
break;
case TAC_PLUS_AUTHEN_STATUS_GETPASS:
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG,
"tacacs status: TAC_PLUS_AUTHEN_STATUS_GETPASS");
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: tac_cont_send called", __FUNCTION__);
if (tac_cont_send(tac_fd, pass) < 0)
{
_pam_log(LOG_ERR,
"error sending continue req to TACACS+ server");
communicating = 0;
}
/* continue the while loop; go read tac response */
break;
case TAC_PLUS_AUTHEN_STATUS_RESTART:
/* try it again */
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG,
"tacacs status: TAC_PLUS_AUTHEN_STATUS_RESTART");
syslog(LOG_ERR, "%s: TAC_PLUS_AUTHEN_STATUS_RESTART not implemented", __FUNCTION__);
abort();
communicating = 0;
break;
case TAC_PLUS_AUTHEN_STATUS_ERROR:
/* server has problems */
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG,
"tacacs status: TAC_PLUS_AUTHEN_STATUS_ERROR");
communicating = 0;
break;
case TAC_PLUS_AUTHEN_STATUS_FOLLOW:
/* server tells to try a different server address */
/* not implemented */
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG,
"tacacs status: TAC_PLUS_AUTHEN_STATUS_FOLLOW");
syslog(LOG_ERR, "%s: TAC_PLUS_AUTHEN_STATUS_FOLLOW not implemented", __FUNCTION__);
abort();
communicating = 0;
break;
default:
if (tac_status < 0) {
/* connection error */
communicating = 0;
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG,
"error communicating with tacacs server");
break;
}
/* unknown response code */
communicating = 0;
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "tacacs status: unknown response 0x%02x", tac_status);
syslog(LOG_ERR, "%s: unknown response 0x%02x", __FUNCTION__, tac_status);
abort();
}
if (resp != NULL) {
free(resp->resp);
free(resp);
}
if (arep.msg != NULL)
free(arep.msg);
tac_free_attrib(arep.attr);
} /* end while(communicating) */
close(tac_fd);
if (status == PAM_SUCCESS || status == PAM_AUTH_ERR)
break;
}
if (status != PAM_SUCCESS && status != PAM_AUTH_ERR)
_pam_log(LOG_ERR, "no more servers to connect");
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: exit with pam status: %d", __FUNCTION__, status);
if (pass != NULL)
{
// sanitize password from memory
explicit_bzero(pass, strlen(pass));
free(pass);
pass = NULL;
}
return status;
} /* pam_sm_authenticate */
/* no-op function to satisfy PAM authentication module */
PAM_EXTERN
int pam_sm_setcred(pam_handle_t *UNUSED(pamh), int UNUSED(flags), int argc, const char **argv)
{
int ctrl = _pam_parse(argc, argv);
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: called (%s)", __FUNCTION__, PACKAGE_STRING);
return PAM_SUCCESS;
} /* pam_sm_setcred */
/* authorizes user on remote TACACS+ server, i.e. checks
* his permission to access requested service
* returns PAM_SUCCESS if the service is allowed
*/
PAM_EXTERN
int pam_sm_acct_mgmt(pam_handle_t *pamh, int UNUSED(flags), int argc,
const char **argv) {
int retval, ctrl, status = PAM_AUTH_ERR;
char *user = NULL;
char *tty = NULL;
char *r_addr = NULL;
struct areply arep;
int tac_fd;
gl_list_t attr;
attr = gl_list_create_empty(GL_ARRAY_LIST, NULL, NULL, NULL, false);
memset(&arep, 0, sizeof(arep));
arep.attr = gl_list_create_empty(GL_ARRAY_LIST, NULL, NULL, NULL, false);
/* this also obtains service name for authorization
this should be normally performed by pam_get_item(PAM_SERVICE)
but since PAM service names are incompatible TACACS+
we have to pass it via command line argument until a better
solution is found ;) */
ctrl = _pam_parse(argc, argv);
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: called (%s)", __FUNCTION__, PACKAGE_STRING);
if ((user = _pam_get_user(pamh)) == NULL)
return PAM_USER_UNKNOWN;
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: username obtained [%s]", __FUNCTION__, user);
tty = _pam_get_terminal(pamh);
if (!strncmp(tty, "/dev/", 5))
tty += 5;
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: tty obtained [%s]", __FUNCTION__, tty);
r_addr = _pam_get_rhost(pamh);
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: rhost obtained [%s]", __FUNCTION__, r_addr);
/* checks if user has been successfully authenticated
by TACACS+; we cannot solely authorize user if it hasn't
been authenticated or has been authenticated by method other
than TACACS+ */
if (active_server.addr == NULL)
{
_pam_log(LOG_ERR, "user not authenticated by TACACS+");
return PAM_AUTH_ERR;
}
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: active server is [%s]", __FUNCTION__,
tac_ntop(active_server.addr->ai_addr));
/* checks for specific data required by TACACS+, which should
be supplied in command line */
if (!*tac_service)
{
_pam_log(LOG_ERR, "SM: TACACS+ service type not configured");
return PAM_AUTH_ERR;
}
if (!*tac_protocol)
{
_pam_log(LOG_ERR, "SM: TACACS+ protocol type not configured (IGNORED)");
}
tac_add_attrib(attr, "service", tac_service);
if (tac_protocol[0] != '\0')
tac_add_attrib(attr, "protocol", tac_protocol);
tac_fd = tac_connect_single(active_server.addr, active_server.key, NULL,
tac_timeout);
if (tac_fd < 0)
{
_pam_log(LOG_ERR, "TACACS+ server unavailable");
tac_free_attrib(attr);
return PAM_AUTH_ERR;
}
retval = tac_author_send(tac_fd, user, tty, r_addr, attr);
tac_free_attrib(attr);
if (retval < 0)
{
_pam_log(LOG_ERR, "error getting authorization");
close(tac_fd);
active_server.addr = NULL;
return PAM_AUTH_ERR;
}
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: sent authorization request", __FUNCTION__);
tac_author_read(tac_fd, &arep);
if (arep.status != AUTHOR_STATUS_PASS_ADD && arep.status != AUTHOR_STATUS_PASS_REPL)
{
_pam_log(LOG_ERR, "TACACS+ authorisation failed for [%s]", user);
if (arep.msg != NULL)
free(arep.msg);
close(tac_fd);
return PAM_PERM_DENIED;
}
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: user [%s] successfully authorized", __FUNCTION__,
user);
status = PAM_SUCCESS;
const void *element;
gl_list_iterator_t attributes_iterator = gl_list_iterator(arep.attr);
while (gl_list_iterator_next(&attributes_iterator, &element, NULL)) {
size_t attribute_len = strlen((const char *) element);
size_t attribute_name_len = strcspn((const char *) element, "=*");
if (attribute_name_len < attribute_len) {
char avpair[attribute_len + 1];
xstrncpy(avpair, element, sizeof(avpair)); /* Also copy terminating NUL */
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: returned attribute `%s' from server",
__FUNCTION__, avpair);
avpair[attribute_name_len] = '='; // replace '*' by '='
size_t i;
for (i = 0; i < attribute_name_len; i++) {
avpair[i] = toupper((unsigned char) avpair[i]);
if (avpair[i] == '-')
avpair[i] = '_';
}
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: setting PAM environment `%s'",
__FUNCTION__, avpair);
/* make returned attributes available for other PAM modules via PAM environment */
if (pam_putenv(pamh, avpair) != PAM_SUCCESS)
syslog(LOG_WARNING, "%s: unable to set PAM environment",
__FUNCTION__);
} else {
syslog(LOG_WARNING, "%s: invalid attribute `%s', no separator",
__FUNCTION__, (const char *) element);
}
}
/* free returned attributes */
gl_list_iterator_free(&attributes_iterator);
tac_free_attrib(arep.attr);
if (arep.msg != NULL)
free(arep.msg);
close(tac_fd);
return status;
} /* pam_sm_acct_mgmt */
/* sends START accounting request to the remote TACACS+ server
* returns PAM error only if the request was refused or there
* were problems connection to the server
*/
/* accounting packets may be directed to any TACACS+ server,
* independent from those used for authentication and authorization;
* it may be also directed to all specified servers
*/
PAM_EXTERN
int pam_sm_open_session(pam_handle_t *pamh, int UNUSED(flags), int argc,
const char **argv)
{
return _pam_account(pamh, argc, argv, TAC_PLUS_ACCT_FLAG_START, NULL);
} /* pam_sm_open_session */
/* sends STOP accounting request to the remote TACACS+ server
* returns PAM error only if the request was refused or there
* were problems connection to the server
*/
PAM_EXTERN
int pam_sm_close_session(pam_handle_t *pamh, int UNUSED(flags), int argc, const char **argv)
{
return _pam_account(pamh, argc, argv, TAC_PLUS_ACCT_FLAG_STOP, NULL);
} /* pam_sm_close_session */
#ifdef PAM_SM_PASSWORD
/* no-op function for future use */
PAM_EXTERN
int pam_sm_chauthtok(pam_handle_t *pamh, int flags, int argc,
const char **argv)
{
int ctrl, retval;
char *user;
char *pass;
char *tty;
char *r_addr;
const void *pam_pass = NULL;
unsigned long srv_i;
int tac_fd, status, msg, communicating;
user = pass = tty = r_addr = NULL;
ctrl = _pam_parse(argc, argv);
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: called (%s)", __FUNCTION__, PACKAGE_STRING);
syslog(LOG_DEBUG, "%s(flags=%d, argc=%d)", __func__, flags, argc);
if ((pam_get_item(pamh, PAM_OLDAUTHTOK, &pam_pass) == PAM_SUCCESS) && (pam_pass != NULL))
{
if ((pass = strdup(pam_pass)) == NULL)
return PAM_BUF_ERR;
}
else
{
pass = strdup("");
}
if ((user = _pam_get_user(pamh)) == NULL)
{
if (pass)
{
free(pass);
}
return PAM_USER_UNKNOWN;
}
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: user [%s] obtained", __FUNCTION__, user);
tty = _pam_get_terminal(pamh);
if (!strncmp(tty, "/dev/", 5))
tty += 5;
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: tty [%s] obtained", __FUNCTION__, tty);
r_addr = _pam_get_rhost(pamh);
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: rhost [%s] obtained", __FUNCTION__, r_addr);
if (PAM_SILENT == (flags & PAM_SILENT))
{
status = PAM_AUTHTOK_ERR;
goto finish;
}
status = PAM_TRY_AGAIN;
for (srv_i = 0; srv_i < tac_srv_no; srv_i++)
{
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: trying srv %lu", __FUNCTION__, srv_i);
tac_fd = tac_connect_single(tac_srv[srv_i].addr, tac_srv[srv_i].key,
NULL, tac_timeout);
if (tac_fd < 0)
{
_pam_log(LOG_ERR, "connection failed srv %lu: %m", srv_i);
continue;
}
if (PAM_PRELIM_CHECK == (flags & PAM_PRELIM_CHECK))
{
if (PAM_TAC_DEBUG == (ctrl & PAM_TAC_DEBUG))
syslog(LOG_DEBUG, "%s: finishing PAM_PRELIM_CHECK with srv %lu",
__FUNCTION__, srv_i);
close(tac_fd);
status = PAM_SUCCESS;
goto finish;
}
if (tac_authen_send(tac_fd, user, "", tty, r_addr,
TAC_PLUS_AUTHEN_CHPASS) < 0)
{
close(tac_fd);
_pam_log(LOG_ERR, "error sending auth req to TACACS+ server");
continue;
}
communicating = 1;
while (communicating) {
struct areply re;
struct pam_message conv_msg;
struct pam_response *resp = NULL;
memset(&conv_msg, 0, sizeof(conv_msg));
memset(&re, 0, sizeof(re));
re.attr = gl_list_create_empty(GL_ARRAY_LIST, NULL, NULL, NULL, false);
msg = tac_authen_read(tac_fd, &re);
if (re.msg != NULL) {
conv_msg.msg = re.msg;
}
/* talk the protocol */
switch (msg)
{
case TAC_PLUS_AUTHEN_STATUS_PASS:
/* success */
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG,
"tacacs status: TAC_PLUS_AUTHEN_STATUS_PASS");
if (conv_msg.msg != NULL) {
conv_msg.msg_style = PAM_TEXT_INFO;
retval = converse(pamh, 1, &conv_msg, &resp);
if (PAM_SUCCESS == retval) {
if (PAM_TAC_DEBUG == (ctrl & PAM_TAC_DEBUG))
syslog(LOG_DEBUG, "send msg=\"%s\"", conv_msg.msg);
} else {
_pam_log(LOG_WARNING,
"%s: error sending msg=\"%s\", retval=%d",
__FUNCTION__, conv_msg.msg, retval);
}
}
status = PAM_SUCCESS;
communicating = 0;
set_active_server(&tac_srv[srv_i]);
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: active srv %lu", __FUNCTION__, srv_i);
break;
case TAC_PLUS_AUTHEN_STATUS_FAIL:
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG,
"tacacs status: TAC_PLUS_AUTHEN_STATUS_FAIL");
if (conv_msg.msg != NULL) {
conv_msg.msg_style = PAM_ERROR_MSG;
retval = converse(pamh, 1, &conv_msg, &resp);
if (PAM_SUCCESS == retval) {
if (PAM_TAC_DEBUG == (ctrl & PAM_TAC_DEBUG))
syslog(LOG_DEBUG, "send msg=\"%s\"", conv_msg.msg);
} else {
_pam_log(LOG_WARNING,
"%s: error sending msg=\"%s\", retval=%d",
__FUNCTION__, conv_msg.msg, retval);
}
}
status = PAM_AUTHTOK_ERR;
communicating = 0;
_pam_log(LOG_ERR, "chauthtok failed: %d", msg);
break;
case TAC_PLUS_AUTHEN_STATUS_GETDATA:
if (PAM_TAC_DEBUG == (ctrl & PAM_TAC_DEBUG))
syslog(LOG_DEBUG,
"tacacs status: TAC_PLUS_AUTHEN_STATUS_GETDATA");
if (conv_msg.msg != NULL) {
int echo_off = (0x1 == (re.flags & 0x1));
conv_msg.msg_style =
echo_off ? PAM_PROMPT_ECHO_OFF : PAM_PROMPT_ECHO_ON;
retval = converse(pamh, 1, &conv_msg, &resp);
if (PAM_SUCCESS == retval) {
if (PAM_TAC_DEBUG == (ctrl & PAM_TAC_DEBUG))
syslog(LOG_DEBUG, "sent msg=\"%s\", resp=\"%s\"",
conv_msg.msg, resp->resp);
if (PAM_TAC_DEBUG == (ctrl & PAM_TAC_DEBUG))
syslog(LOG_DEBUG, "%s: calling tac_cont_send",
__FUNCTION__);
if (0 > tac_cont_send_seq(tac_fd, resp->resp,
re.seq_no + 1))
{
_pam_log(LOG_ERR,
"error sending continue req to TACACS+ server");
communicating = 0;
}
}
else
{
_pam_log(LOG_WARNING,
"%s: error sending msg=\"%s\", retval=%d",
__FUNCTION__, conv_msg.msg, retval);
communicating = 0;
}
}
else
{
syslog(LOG_ERR,
"GETDATA response with no message, returning PAM_TRY_AGAIN");
communicating = 0;
}
break;
case TAC_PLUS_AUTHEN_STATUS_GETUSER:
/* not implemented */
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG,
"tacacs status: TAC_PLUS_AUTHEN_STATUS_GETUSER");