/* 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 flags,
int argc, const char **argv) {
int rc;
char *user;
_pam_get_user(pamh, &user);
task_id = session_taskid; /* task_id must match start */
rc = _pam_account(pamh, argc, argv, TAC_PLUS_ACCT_FLAG_STOP, NULL);
__update_loguid(user); /* now dead, cleanup mapping */
return rc;
} /* pam_sm_close_session */
/* 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;
int 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 (pam_tacplus v%u.%u.%u)"
, __FUNCTION__, PAM_TAC_VMAJ, PAM_TAC_VMIN, PAM_TAC_VPAT);
syslog(LOG_DEBUG, "%s(flags=%d, argc=%d)", __func__, flags, argc);
// read config file
_read_config(ctrl);
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) {
xfree(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 %d", __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 %d: %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 %d",
__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 = { .attr = NULL, .msg = NULL, status = 0, flags = 0 };
struct pam_message conv_msg = { .msg_style = 0, .msg = NULL };
struct pam_response *resp = NULL;
msg = tac_authen_read(tac_fd, &re);
if (NULL != re.msg) {
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 (NULL != conv_msg.msg) {
int retval = -1;
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;
if (active_server.addr != NULL)
{
xfree(active_server.addr);
}
active_server.addr = (struct addrinfo*)xcalloc(1, sizeof(struct addrinfo));
bcopy(tac_srv[srv_i].addr, active_server.addr, sizeof(struct addrinfo));
if (active_server.key != NULL)
{
xfree(active_server.key);
}
active_server.key = xstrdup(tac_srv[srv_i].key);
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: active srv %d", __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 (NULL != conv_msg.msg) {
int retval = -1;
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 (NULL != conv_msg.msg) {
int retval = -1;
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");
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: calling tac_cont_send", __FUNCTION__);
if (tac_cont_send(tac_fd, pass) < 0) {
_pam_log (LOG_ERR, "error sending continue req to TACACS+ server");
communicating = 0;
break;
}
/* 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");
/*
* not implemented
* WdJ: I *think* you can just do tac_authen_send(user, pass) again
* but I'm not sure
*/
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");
communicating = 0;
break;
default:
if (msg < 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", msg);
}
if (NULL != resp) {
xfree(resp->resp);
xfree(resp);
}
xfree(re.msg);
} /* end while(communicating) */
close(tac_fd);
if (status == PAM_SUCCESS || status == PAM_AUTHTOK_ERR)
break;
}
finish:
if (status != PAM_SUCCESS && status != PAM_AUTHTOK_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 (NULL != pass) {
bzero(pass, strlen(pass));
xfree(pass);
pass = NULL;
}
return status;
} /* pam_sm_chauthtok */
#endif
#ifdef PAM_STATIC
struct pam_module _pam_tacplus_modstruct {
"pam_tacplus",
pam_sm_authenticate,
pam_sm_setcred,
pam_sm_acct_mgmt,
pam_sm_open_session,
pam_sm_close_session,
#ifdef PAM_SM_PASSWORD
pam_sm_chauthtok
#else
NULL
#endif
};
/* 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;
int 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 (pam_tacplus v%u.%u.%u)",
__FUNCTION__, PAM_TAC_VMAJ, PAM_TAC_VMIN, PAM_TAC_VPAT);
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);
// read config file
_read_config(ctrl);
retval = tacacs_get_password (pamh, flags, ctrl, &pass);
if (retval != PAM_SUCCESS || pass == NULL || *pass == '\0') {
_pam_log(LOG_ERR, "unable to obtain password");
xfree(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");
xfree(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/", 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);
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 %d", __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 %d: %m", srv_i);
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");
continue;
}
communicating = 1;
while (communicating) {
struct areply re = { .attr = NULL, .msg = NULL, status = 0, flags = 0 };
struct pam_message conv_msg = { .msg_style = 0, .msg = NULL };
struct pam_response *resp = NULL;
msg = tac_authen_read(tac_fd, &re);
if (NULL != re.msg) {
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 (NULL != conv_msg.msg) {
int retval = -1;
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;
if (active_server.addr != NULL)
{
xfree(active_server.addr);
}
active_server.addr = (struct addrinfo*)xcalloc(1, sizeof(struct addrinfo));
bcopy(tac_srv[srv_i].addr, active_server.addr, sizeof(struct addrinfo));
if (active_server.key != NULL)
{
xfree(active_server.key);
}
active_server.key = xstrdup(tac_srv[srv_i].key);
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: active srv %d", __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 (NULL != conv_msg.msg) {
int retval = -1;
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_AUTH_ERR;
communicating = 0;
_pam_log(LOG_ERR, "auth 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 (NULL != conv_msg.msg) {
int retval = -1;
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");
status = PAM_AUTH_ERR;
communicating = 0;
}
}
else {
_pam_log(LOG_WARNING, "%s: error sending msg=\"%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");
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");
/*
* not implemented
* WdJ: I *think* you can just do tac_authen_send(user, pass) again
* but I'm not sure
*/
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");
communicating = 0;
break;
default:
if (msg < 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", msg);
}
if (NULL != resp)
{
if (resp->resp != NULL)
{
xfree(resp->resp);
}
xfree(resp);
}
if (re.msg != NULL)
{
xfree(re.msg);
}
} /* 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 (NULL != pass) {
bzero(pass, strlen (pass));
xfree(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 * pamh, int flags,
int argc, const char **argv) {
int ctrl = _pam_parse (argc, argv);
if (ctrl & PAM_TAC_DEBUG)
syslog (LOG_DEBUG, "%s: called (pam_tacplus v%u.%u.%u)"
, __FUNCTION__, PAM_TAC_VMAJ, PAM_TAC_VMIN, PAM_TAC_VPAT);
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 flags,
int argc, const char **argv) {
int retval, ctrl, status=PAM_AUTH_ERR;
char *user;
char *tty;
char *r_addr;
struct areply arep;
struct tac_attrib *attr = NULL;
int tac_fd;
user = tty = r_addr = NULL;
memset(&arep, 0, sizeof(arep));
/* 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 (pam_tacplus v%u.%u.%u)"
, __FUNCTION__, PAM_TAC_VMAJ, PAM_TAC_VMIN, PAM_TAC_VPAT);
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);
// read config file
_read_config(ctrl);
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");
if(arep.msg != NULL)
xfree (arep.msg);
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");
if(arep.msg != NULL)
xfree (arep.msg);
close(tac_fd);
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)
xfree (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;
attr = arep.attr;
while (attr != NULL) {
char attribute[attr->attr_len];
char value[attr->attr_len];
char *sep;
sep = index(attr->attr, '=');
if(sep == NULL)
sep = index(attr->attr, '*');
if(sep != NULL) {
bcopy(attr->attr, attribute, attr->attr_len-strlen(sep));
attribute[attr->attr_len-strlen(sep)] = '\0';
bcopy(sep, value, strlen(sep));
value[strlen(sep)] = '\0';
size_t i;
for (i = 0; attribute[i] != '\0'; i++) {
attribute[i] = toupper(attribute[i]);
if (attribute[i] == '-')
attribute[i] = '_';
}
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: returned attribute `%s%s' from server", __FUNCTION__, attribute, value);
/* make returned attributes available for other PAM modules via PAM environment */
if (pam_putenv(pamh, strncat(attribute, value, strlen(value))) != PAM_SUCCESS)
syslog(LOG_WARNING, "%s: unable to set PAM environment", __FUNCTION__);
} else {
syslog(LOG_WARNING, "%s: invalid attribute `%s', no separator", __FUNCTION__, attr->attr);
}
attr = attr->next;
}
/* free returned attributes */
if(arep.attr != NULL)
tac_free_attrib(&arep.attr);
if(arep.msg != NULL)
xfree (arep.msg);
close(tac_fd);
return status;
} /* pam_sm_acct_mgmt */
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 srv_i, tac_fd;
typemsg = tac_acct_flag2str(type);
ctrl = _pam_parse (argc, argv);
if (ctrl & PAM_TAC_DEBUG) {
syslog (LOG_DEBUG, "%s: [%s] called (pam_tacplus v%u.%u.%u)",
__FUNCTION__, typemsg, PAM_TAC_VMAJ, PAM_TAC_VMIN, PAM_TAC_VPAT);
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);
// read config file
_read_config(ctrl);
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 %d)", __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;
}
/* Tested for servers that require password change during challenge/response */
PAM_EXTERN
int pam_sm_chauthtok(pam_handle_t * pamh, int flags,
int argc, const char **argv) {
int ctrl;
char *user;
char *pass;
char *tty;
char *r_addr;
const void *pam_pass = NULL;
int srv_i;
int status;
user = pass = tty = r_addr = NULL;
ctrl = _pam_parse(argc, argv);
if (ctrl & PAM_TAC_DEBUG)
syslog (LOG_DEBUG, "%s: called (pam_tacplus v%u.%u.%u) (flags=%d, argc=%d)",
__func__, PAM_TAC_VMAJ, PAM_TAC_VMIN, PAM_TAC_VPAT, 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("");
}
_pam_get_user(pamh, &user);
if (user == NULL) {
if(pass) {
free(pass);
}
return PAM_USER_UNKNOWN;
}
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: user [%s] obtained", __func__, user);
_pam_get_terminal(pamh, &tty);
if (tty && !strncmp(tty, "/dev/", 5))
tty += 5;
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: tty [%s] obtained", __func__, tty?tty:"UNKNOWN");
_pam_get_rhost(pamh, &r_addr);
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: rhost [%s] obtained", __func__, r_addr?r_addr:"UNKNOWN");
if (PAM_SILENT != (flags & PAM_SILENT))
status = do_tac_connect(ctrl, NULL, user, pass, tty, r_addr, NULL, NULL, pamh);
else
status = PAM_AUTHTOK_ERR;
if (status != PAM_SUCCESS && status != PAM_AUTHTOK_ERR)
_pam_log(LOG_ERR, "no more servers to connect");
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: exit with pam status: %d", __func__, status);
if (NULL != pass) {
bzero(pass, strlen(pass));
free(pass);
pass = NULL;
}
return status;
} /* pam_sm_chauthtok */
/* 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 flags,
int argc, const char **argv) {
int ctrl, status=PAM_AUTH_ERR;
char *user;
char *tty;
char *r_addr;
struct areply arep;
struct tac_attrib *attr_s = NULL, *attr;
int tac_fd = -1;
user = tty = r_addr = NULL;
memset(&arep, 0, sizeof(arep));
/* 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 (pam_tacplus v%u.%u.%u)",
__func__, PAM_TAC_VMAJ, PAM_TAC_VMIN, PAM_TAC_VPAT);
_pam_get_user(pamh, &user);
if (user == NULL)
return PAM_USER_UNKNOWN;
_pam_get_terminal(pamh, &tty);
if(!strncmp(tty, "/dev/", 5))
tty += 5;
_pam_get_rhost(pamh, &r_addr);
/* checks for specific data required by TACACS+, which should
be supplied in pam module command line */
if(!*tac_service) {
_pam_log (LOG_ERR, "TACACS+ service type not configured");
return PAM_AUTH_ERR;
}
tac_add_attrib(&attr_s, "service", tac_service);
if(tac_protocol != NULL && tac_protocol[0] != '\0')
tac_add_attrib(&attr_s, "protocol", tac_protocol);
else
_pam_log (LOG_ERR, "TACACS+ protocol type not configured (IGNORED)");
tac_add_attrib(&attr_s, "cmd", "");
memset(&arep, 0, sizeof arep);
/*
* Check if user is authorized, independently of authentication.
* Authentication may have happened via ssh public key, rather than
* via TACACS+. PAM should not normally get to this entry point if
* user is not yet authenticated.
* We only write the mapping entry (if needed) when authorization
* is succesful.
* attr is not used here, but having a non-NULL value is how
* talk_tac_server() distinguishes that it is an acct call, vs auth
* TODO: use a different mechanism
*/
status = do_tac_connect(ctrl, &tac_fd, user, NULL, tty, r_addr, &attr_s,
&arep, pamh);
tac_free_attrib(&attr_s);
if(active_server.addr == NULL || tac_fd < 0) {
/* we need to return PAM_AUTHINFO_UNAVAIL here, rather than
* PAM_AUTH_ERR, or we can't use "ignore" in the pam configuration
*/
status = PAM_AUTHINFO_UNAVAIL;
goto cleanup;
}
if(status) {
if (ctrl & PAM_TAC_DEBUG)
_pam_log(LOG_NOTICE, "No TACACS mapping for %s after auth failure",
user);
goto cleanup;
}
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: user [%s] successfully authorized", __func__,
user);
attr = arep.attr;
while (attr != NULL) {
char attribute[attr->attr_len];
char value[attr->attr_len];
char attrenv[attr->attr_len];
char *sep;
sep = index(attr->attr, '=');
if(sep == NULL)
sep = index(attr->attr, '*');
if(sep != NULL) {
bcopy(attr->attr, attribute, attr->attr_len-strlen(sep));
attribute[attr->attr_len-strlen(sep)] = '\0';
bcopy(sep, value, strlen(sep));
value[strlen(sep)] = '\0';
size_t i;
for (i = 0; attribute[i] != '\0'; i++) {
attribute[i] = toupper(attribute[i]);
if (attribute[i] == '-')
attribute[i] = '_';
}
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: returned attribute `%s(%s)' from server",
__func__, attribute, value);
if(strncmp(attribute, "PRIV", 4) == 0) {
char *ok;
/* because of the separation above, value will start with
* the separator, which we don't want. */
priv_level = (unsigned)strtoul(value+1, &ok, 0);
/* if this fails, we leave priv_level at 0, which is
* least privileged, so that's OK, but at least report it
*/
if (ok == value)
_pam_log (LOG_WARNING,
"%s: non-numeric privilege for %s, got (%s)",
__func__, attribute, value+1);
}
/*
* make returned attributes available for other PAM modules via PAM
* environment. Since separator can be = or *, ensure it's = for
* the env.
*/
snprintf(attrenv, sizeof attribute, "%s=%s", attribute, value+1);
if (pam_putenv(pamh, attrenv) != PAM_SUCCESS)
_pam_log(LOG_WARNING, "%s: unable to set PAM environment (%s)",
__func__, attribute);
} else {
syslog(LOG_WARNING, "%s: invalid attribute `%s', no separator",
__func__, attr->attr);
}
attr = attr->next;
}
update_mapped(pamh, user, priv_level, r_addr);
cleanup:
/* free returned attributes */
if(arep.attr != NULL)
tac_free_attrib(&arep.attr);
if(arep.msg != NULL)
free (arep.msg);
if(tac_fd >= 0) {
active_server.addr = NULL;
close(tac_fd);
tac_fd = -1;
}
return status;
} /* pam_sm_acct_mgmt */
/*
* Send an accounting record to the TACACS+ server.
* We send the start/stop accounting records even if the user is not known
* to the TACACS+ server. This seems non-intuitive, but it's the way
* this code is written to work.
*/
int _pam_account(pam_handle_t *pamh, int argc, const char **argv,
int type, char *cmd) {
int retval;
int ctrl;
char *user = NULL;
char *tty = NULL;
char *r_addr = NULL;
char *typemsg;
int status = PAM_SESSION_ERR;
int srv_i, tac_fd;
typemsg = tac_acct_flag2str(type);
ctrl = _pam_parse (argc, argv);
if (ctrl & PAM_TAC_DEBUG)
syslog (LOG_DEBUG, "%s: [%s] called (pam_tacplus v%u.%u.%u)",
__func__, typemsg, PAM_TAC_VMAJ, PAM_TAC_VMIN, PAM_TAC_VPAT);
_pam_get_user(pamh, &user);
if (user == NULL)
return PAM_USER_UNKNOWN;
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: username [%s] obtained", __func__, user);
if (!task_id)
#if defined(HAVE_OPENSSL_RAND_H) && defined(HAVE_LIBCRYPTO)
RAND_pseudo_bytes((unsigned char *) &task_id, sizeof(task_id));
#else
task_id = (short unsigned int) tac_magic();
#endif
_pam_get_terminal(pamh, &tty);
if(!strncmp(tty, "/dev/", 5))
tty += 5;
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: tty [%s] obtained", __func__, tty);
_pam_get_rhost(pamh, &r_addr);
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: rhost [%s] obtained", __func__, r_addr);
/* checks for specific data required by TACACS+, which should
be supplied in command line */
if(tac_protocol[0] == '\0') {
_pam_log (LOG_ERR, "ACC: TACACS+ protocol type not configured");
return PAM_AUTH_ERR;
}
/* 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);
}
/*
* If PAM_SESSION_ERR is used, then the pam config can't
* ignore server failures, so use PAM_AUTHINFO_UNAVAIL.
*
* We have to make a new connection each time, because libtac is single
* threaded (doesn't support multiple connects at the same time due to
* use of globals)), and doesn't have support for persistent connections.
* That's fixable, but not worth the effort at this point.
*
* TODO: this should be converted to use do_tac_connect eventually.
*/
status = PAM_AUTHINFO_UNAVAIL;
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, __vrfname);
if (tac_fd < 0) {
_pam_log(LOG_WARNING, "%s: error sending %s (fd)", __func__,
typemsg);
continue;
}
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: connected with fd=%d to srv[%d] %s", __func__,
tac_fd, srv_i, tac_srv[srv_i].addr ?
tac_ntop(tac_srv[srv_i].addr->ai_addr) : "not set");
retval = _pam_send_account(tac_fd, type, user, tty, r_addr, cmd);
if (retval < 0) {
_pam_log(LOG_WARNING, "%s: error sending %s (acct)",
__func__, typemsg);
} else {
status = PAM_SUCCESS;
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: [%s] for [%s] sent", __func__, typemsg, user);
}
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;
}
/* 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, *puser;
char *pass;
char *tty;
char *r_addr;
int status;
priv_level = 0;
user = pass = tty = r_addr = NULL;
ctrl = _pam_parse(argc, argv);
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: called (pam_tacplus v%u.%u.%u)",
__func__, PAM_TAC_VMAJ, PAM_TAC_VMIN, PAM_TAC_VPAT);
/* reset static state in case we are re-entered */
_reset_saved_user(ctrl & PAM_TAC_DEBUG);
/*
* If a mapped user entry already exists, we are probably being
* used for su or sudo, so we need to get the original user password,
* rather than the mapped user.
* Decided based on auid != uid and then do the lookup, similar to
* find_pw_user() in nss_tacplusc
*/
_pam_get_user(pamh, &puser);
user = get_user_to_auth(puser);
if (user == NULL)
return PAM_USER_UNKNOWN;
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: user [%s] obtained", __func__, 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");
status = PAM_CRED_INSUFFICIENT;
goto err;
}
retval = pam_set_item (pamh, PAM_AUTHTOK, pass);
if (retval != PAM_SUCCESS) {
_pam_log(LOG_ERR, "unable to set password");
status = PAM_CRED_INSUFFICIENT;
goto err;
}
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: password obtained", __func__);
_pam_get_terminal(pamh, &tty);
if (!strncmp(tty, "/dev/", 5))
tty += 5;
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: tty [%s] obtained", __func__, tty);
_pam_get_rhost(pamh, &r_addr);
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: rhost [%s] obtained", __func__, r_addr);
status = do_tac_connect(ctrl, NULL, user, pass, tty, r_addr, NULL, NULL, pamh);
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: exit with pam status: %d", __func__, status);
err:
if (user && user != puser)
free(user); /* it was stdrup'ed */
if (NULL != pass) {
bzero(pass, strlen (pass));
free(pass);
}
return status;
} /* pam_sm_authenticate */
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;
int srv_i;
int tac_fd;
int status = PAM_TRY_AGAIN;
int seq = 0;
user = pass = tty = r_addr = NULL;
ctrl = _pam_parse (argc, argv);
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: called (pam_tacplus v%u.%u.%u)"
, __FUNCTION__, PAM_TAC_VMAJ, PAM_TAC_VMIN, PAM_TAC_VPAT);
/* Preliminary call to check readiness of our module */
if (flags & PAM_PRELIM_CHECK) {
/* Can we connect to TACACS? */
for (srv_i = 0; srv_i < tac_srv_no; srv_i++) {
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: trying srv %d", __FUNCTION__, srv_i );
tac_fd = tac_connect_single(tac_srv[srv_i], tac_srv_key[srv_i]);
if (tac_fd < 0) {
_pam_log (LOG_ERR, "connection failed srv %d: %m", srv_i);
if (srv_i == tac_srv_no-1) {
_pam_log (LOG_ERR, "no more servers to connect");
return PAM_TRY_AGAIN;
}
continue;
}
}
close(tac_fd);
return PAM_SUCCESS;
}
if ((user = _pam_get_user(pamh)) == NULL)
return PAM_USER_UNKNOWN;
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: user [%s] obtained", __FUNCTION__, user);
/* CHPASS does not send a password in data field,
* user is prompted by a GETDATA reply packet
*/
pass = malloc(5);
strcpy(pass,"null");
tty = _pam_get_terminal(pamh);
if (!strncmp (tty, "/dev/", 5))
tty += 5;
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: tty [%s] obtained", __FUNCTION__, tty);
r_addr = _pam_get_rhost(pamh);
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: rhost [%s] obtained", __FUNCTION__, r_addr);
/* Attempt server connect */
for (srv_i = 0; srv_i < tac_srv_no; srv_i++) {
status = TAC_PLUS_AUTHEN_STATUS_FAIL;
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: trying srv %d", __FUNCTION__, srv_i );
tac_fd = tac_connect_single(tac_srv[srv_i], tac_srv_key[srv_i]);
if (tac_fd < 0) {
_pam_log (LOG_ERR, "connection failed srv %d: %m", srv_i);
if (srv_i == tac_srv_no-1) {
_pam_log (LOG_ERR, "no more servers to connect");
return PAM_AUTHINFO_UNAVAIL;
}
continue;
}
/* Send AUTHEN/START */
if (tac_authen_send(tac_fd, user, pass, tty, r_addr, TAC_PLUS_AUTHEN_CHPASS, ctrl) < 0) {
_pam_log (LOG_ERR, "error sending auth req to TACACS+ server");
status = PAM_AUTHINFO_UNAVAIL;
} else {
/* Read AUTHEN/REPLY and act on status */
struct msg_status *msgstatus = malloc(sizeof(msg_status));
do
{
tac_authen_read(msgstatus, tac_fd, ctrl, &seq);
status = msgstatus->status;
switch (status) {
case TAC_PLUS_AUTHEN_STATUS_GETPASS:
/* AUTHEN/CONT with password */
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: tac_cont_send called", __FUNCTION__);
if (tac_cont_send(tac_fd, pass, ctrl, seq+1) < 0) {
_pam_log (LOG_ERR, "error sending continue req to TACACS+ server");
status = PAM_AUTHINFO_UNAVAIL;
}
break;
case TAC_PLUS_AUTHEN_STATUS_GETDATA: {
/* Get data from user with pam conversation */
struct pam_message msg;
struct pam_response *resp = NULL;
int retval;
char *user_data = NULL;
/* set up conversation call */
msg.msg_style = PAM_PROMPT_ECHO_OFF;
msg.msg = malloc(100);
strcpy((char *)msg.msg,msgstatus->server_msg);
if ((retval = converse (pamh, 1, &msg, &resp)) != PAM_SUCCESS) {
status = PAM_AUTHINFO_UNAVAIL;
} else {
if (resp != NULL) {
if (resp->resp == NULL && (ctrl & PAM_TAC_DEBUG))
_pam_log (LOG_DEBUG, "pam_sm_authenticate: NULL given by user for GETDATA request");
user_data = resp->resp;
resp->resp = NULL;
} else {
if (ctrl & PAM_TAC_DEBUG) {
_pam_log (LOG_DEBUG, "pam_sm_authenticate: no error reported");
_pam_log (LOG_DEBUG, "getting data from user - NULL returned!?");
}
return PAM_CONV_ERR;
}
/* AUTHEN/CONT with data */
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: tac_cont_send called", __FUNCTION__);
if (tac_cont_send(tac_fd, user_data, ctrl, seq+1) < 0) {
_pam_log (LOG_ERR, "error sending continue req to TACACS+ server");
status = PAM_AUTHINFO_UNAVAIL;
}
}
free(msg.msg);
}
break;
case TAC_PLUS_AUTHEN_STATUS_GETUSER:
/* AUTHEN/CONT with username */
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: tac_cont_send called", __FUNCTION__);
if (tac_cont_send(tac_fd, user, ctrl, seq+1) < 0) {
_pam_log (LOG_ERR, "error sending continue req to TACACS+ server");
status = PAM_AUTHINFO_UNAVAIL;
}
break;
}
} while ( (status == TAC_PLUS_AUTHEN_STATUS_GETDATA) ||
(status == TAC_PLUS_AUTHEN_STATUS_GETPASS) ||
(status == TAC_PLUS_AUTHEN_STATUS_GETUSER) );
if (status != TAC_PLUS_AUTHEN_STATUS_PASS) {
_pam_log (LOG_ERR, "auth failed: %d", status);
status = PAM_AUTHTOK_ERR;
} else {
/* OK, we got authenticated; save the server that
accepted us for pam_sm_acct_mgmt and exit the loop */
status = PAM_SUCCESS;
active_server = tac_srv[srv_i];
active_key = tac_srv_key[srv_i];
close(tac_fd);
break;
}
}
close(tac_fd);
}
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: exit with pam status: %i", __FUNCTION__, status);
bzero (pass, strlen (pass));
free(pass);
pass = NULL;
return status;
} /* pam_sm_chauthtok */
/* 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 flags,
int argc, const char **argv) {
int retval, ctrl, status=PAM_AUTH_ERR;
char *user;
char *tty;
char *r_addr;
struct areply arep;
struct tac_attrib *attr = NULL;
int tac_fd;
user = tty = r_addr = NULL;
/* 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)
_pam_log (LOG_DEBUG, "%s: called (pam_tacplus v%u.%u.%u)"
, __FUNCTION__, PAM_TAC_VMAJ, PAM_TAC_VMIN, PAM_TAC_VPAT);
if ((user = _pam_get_user(pamh)) == NULL)
return PAM_USER_UNKNOWN;
if (ctrl & PAM_TAC_DEBUG)
_pam_log(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)
_pam_log(LOG_DEBUG, "%s: tty obtained [%s]", __FUNCTION__, tty);
r_addr = _pam_get_rhost(pamh);
if (ctrl & PAM_TAC_DEBUG)
_pam_log(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) {
_pam_log (LOG_ERR, "user not authenticated by TACACS+");
return PAM_AUTH_ERR;
}
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: active server is [%s]", __FUNCTION__,
tac_ntop(active_server->ai_addr, active_server->ai_addrlen));
/* checks for specific data required by TACACS+, which should
be supplied in command line */
if(tac_service == NULL || *tac_service == '\0') {
_pam_log (LOG_ERR, "TACACS+ service type not configured");
return PAM_AUTH_ERR;
}
if(tac_protocol == NULL || *tac_protocol == '\0') {
_pam_log (LOG_ERR, "TACACS+ protocol type not configured");
return PAM_AUTH_ERR;
}
tac_add_attrib(&attr, "service", tac_service);
tac_add_attrib(&attr, "protocol", tac_protocol);
tac_fd = tac_connect_single(active_server, active_key);
if(tac_fd < 0) {
_pam_log (LOG_ERR, "TACACS+ server unavailable");
if(arep.msg != NULL) free (arep.msg);
close(tac_fd);
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");
if(arep.msg != NULL) free (arep.msg);
close(tac_fd);
return PAM_AUTH_ERR;
}
if (ctrl & PAM_TAC_DEBUG)
_pam_log(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)
_pam_log(LOG_DEBUG, "%s: user [%s] successfully authorized", __FUNCTION__, user);
status = PAM_SUCCESS;
attr = arep.attr;
while (attr != NULL) {
char attribute[attr->attr_len];
char value[attr->attr_len];
char *sep;
sep = index(attr->attr, '=');
if(sep == NULL)
sep = index(attr->attr, '*');
if(sep != NULL) {
bcopy(attr->attr, attribute, attr->attr_len-strlen(sep));
attribute[attr->attr_len-strlen(sep)] = '\0';
bcopy(sep, value, strlen(sep));
value[strlen(sep)] = '\0';
size_t i;
for (i = 0; attribute[i] != '\0'; i++) {
attribute[i] = toupper(attribute[i]);
if (attribute[i] == '-')
attribute[i] = '_';
}
if (ctrl & PAM_TAC_DEBUG)
_pam_log(LOG_DEBUG, "%s: returned attribute `%s%s' from server", __FUNCTION__, attribute, value);
/* make returned attributes available for other PAM modules via PAM environment */
if (pam_putenv(pamh, strncat(attribute, value, strlen(value))) != PAM_SUCCESS)
_pam_log(LOG_WARNING, "%s: unable to set PAM environment", __FUNCTION__);
} else {
_pam_log(LOG_WARNING, "%s: invalid attribute `%s', no separator", __FUNCTION__, attr->attr);
}
attr = attr->next;
}
/* free returned attributes */
if(arep.attr != NULL) tac_free_attrib(&arep.attr);
if(arep.msg != NULL) free (arep.msg);
close(tac_fd);
return status;
} /* pam_sm_acct_mgmt */
/* 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;
int srv_i;
int tac_fd;
int status = PAM_AUTH_ERR;
int seq = 0;
user = pass = tty = r_addr = NULL;
ctrl = _pam_parse (argc, argv);
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: called (pam_tacplus v%u.%u.%u)"
, __FUNCTION__, PAM_TAC_VMAJ, PAM_TAC_VMIN, PAM_TAC_VPAT);
if ((user = _pam_get_user(pamh)) == NULL)
return PAM_USER_UNKNOWN;
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: user [%s] obtained", __FUNCTION__, user);
/* uwzgledniac PAM_DISALLOW_NULL_AUTHTOK */
retval = tacacs_get_password (pamh, flags, ctrl, &pass);
if (retval != PAM_SUCCESS || pass == NULL || *pass == '\0') {
_pam_log (LOG_ERR, "unable to obtain password");
return PAM_CRED_INSUFFICIENT;
}
retval = pam_set_item (pamh, PAM_AUTHTOK, pass);
if (retval != PAM_SUCCESS) {
_pam_log (LOG_ERR, "unable to set password");
return PAM_CRED_INSUFFICIENT;
}
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: password obtained", __FUNCTION__);
tty = _pam_get_terminal(pamh);
if (!strncmp (tty, "/dev/", 5))
tty += 5;
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: tty [%s] obtained", __FUNCTION__, tty);
r_addr = _pam_get_rhost(pamh);
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: rhost [%s] obtained", __FUNCTION__, r_addr);
/* Attempt server connect */
for (srv_i = 0; srv_i < tac_srv_no; srv_i++) {
status = TAC_PLUS_AUTHEN_STATUS_FAIL;
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: trying srv %d", __FUNCTION__, srv_i );
tac_fd = tac_connect_single(tac_srv[srv_i], tac_srv_key[srv_i]);
if (tac_fd < 0) {
_pam_log (LOG_ERR, "connection failed srv %d: %m", srv_i);
if (srv_i == tac_srv_no-1) {
_pam_log (LOG_ERR, "no more servers to connect");
return PAM_AUTHINFO_UNAVAIL;
}
continue;
}
/* Send AUTHEN/START */
if (tac_authen_send(tac_fd, user, pass, tty, r_addr, TAC_PLUS_AUTHEN_LOGIN, ctrl) < 0) {
_pam_log (LOG_ERR, "error sending auth req to TACACS+ server");
status = PAM_AUTHINFO_UNAVAIL;
} else {
/* Read AUTHEN/REPLY and act on status */
struct msg_status *msgstatus = malloc(sizeof(msg_status));
do
{
tac_authen_read(msgstatus, tac_fd, ctrl, &seq);
status = msgstatus->status;
switch (status) {
case TAC_PLUS_AUTHEN_STATUS_GETPASS:
/* AUTHEN/CONT with password */
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: tac_cont_send called", __FUNCTION__);
if (tac_cont_send(tac_fd, pass, ctrl, seq+1) < 0) {
_pam_log (LOG_ERR, "error sending continue req to TACACS+ server");
status = PAM_MAXTRIES;
}
break;
case TAC_PLUS_AUTHEN_STATUS_GETDATA: {
/* The only GETDATA request should be if the user's password
* has expired and ACS is requesting a new password
*
* Check if a conversation function has been set and either
* return a PAM_AUTHTOK_EXPIRED or start a conversation
* with the user for to change the password
*/
if (!strcmp(tty,"http")) {
status = PAM_NEW_AUTHTOK_REQD;
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: expired", __FUNCTION__);
} else {
/* Get data from user with pam conversation */
struct pam_message msg;
struct pam_response *resp = NULL;
int retval;
char *user_data = NULL;
/* set up conversation call */
msg.msg_style = PAM_PROMPT_ECHO_OFF;
msg.msg = malloc(100);
strcpy((char *)msg.msg,msgstatus->server_msg);
if ((retval = converse (pamh, 1, &msg, &resp)) != PAM_SUCCESS) {
status = PAM_AUTHINFO_UNAVAIL;
} else {
if (resp != NULL) {
if (resp->resp == NULL && (ctrl & PAM_TAC_DEBUG))
_pam_log (LOG_DEBUG, "pam_sm_authenticate: NULL given by user for GETDATA request");
user_data = resp->resp;
resp->resp = NULL;
} else {
if (ctrl & PAM_TAC_DEBUG) {
_pam_log (LOG_DEBUG, "pam_sm_authenticate: no error reported");
_pam_log (LOG_DEBUG, "getting data from user - NULL returned!?");
}
return PAM_CONV_ERR;
}
/* AUTHEN/CONT with data */
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: tac_cont_send called", __FUNCTION__);
if (tac_cont_send(tac_fd, user_data, ctrl, seq+1) < 0) {
_pam_log (LOG_ERR, "error sending continue req to TACACS+ server");
status = PAM_AUTHINFO_UNAVAIL;
}
}
free(msg.msg);
}
}
break;
case TAC_PLUS_AUTHEN_STATUS_GETUSER:
/* AUTHEN/CONT with username */
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: tac_cont_send called", __FUNCTION__);
if (tac_cont_send(tac_fd, user, ctrl, seq+1) < 0) {
_pam_log (LOG_ERR, "error sending continue req to TACACS+ server");
status = PAM_AUTHINFO_UNAVAIL;
}
break;
}
} while ( (status == TAC_PLUS_AUTHEN_STATUS_GETDATA) ||
(status == TAC_PLUS_AUTHEN_STATUS_GETPASS) ||
(status == TAC_PLUS_AUTHEN_STATUS_GETUSER) );
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: out of while loop status=%d", __FUNCTION__,status);
if (status == TAC_PLUS_AUTHEN_STATUS_PASS) {
/* OK, we got authenticated; save the server that
accepted us for pam_sm_acct_mgmt and exit the loop */
status = PAM_SUCCESS;
active_server = tac_srv[srv_i];
active_key = tac_srv_key[srv_i];
} else if (status != PAM_NEW_AUTHTOK_REQD) {
_pam_log (LOG_ERR, "auth failed: %d", status);
status = PAM_AUTH_ERR;
}
}
close(tac_fd);
/* TODO: Allow time for tac server to reply
* TODO: Check if reply received before connecting to next server
*/
}
if (ctrl & PAM_TAC_DEBUG)
_pam_log (LOG_DEBUG, "%s: exit with pam status: %i", __FUNCTION__, status);
bzero (pass, strlen (pass));
free(pass);
pass = NULL;
return status;
} /* pam_sm_authenticate */
/* 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;
int 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 (pam_tacplus v%u.%u.%u)",
__FUNCTION__, PAM_TAC_VMAJ, PAM_TAC_VMIN, PAM_TAC_VPAT);
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);
/* uwzgledniac PAM_DISALLOW_NULL_AUTHTOK */
retval = tacacs_get_password (pamh, flags, ctrl, &pass);
if (retval != PAM_SUCCESS || pass == NULL || *pass == '\0') {
_pam_log(LOG_ERR, "unable to obtain password");
return PAM_CRED_INSUFFICIENT;
}
retval = pam_set_item (pamh, PAM_AUTHTOK, pass);
if (retval != PAM_SUCCESS) {
_pam_log(LOG_ERR, "unable to set password");
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/", 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);
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 %d", __FUNCTION__, srv_i );
tac_fd = tac_connect_single(tac_srv[srv_i].addr, tac_srv[srv_i].key);
if (tac_fd < 0) {
_pam_log(LOG_ERR, "connection failed srv %d: %m", srv_i);
continue;
}
if (tac_authen_send(tac_fd, user, pass, tty, r_addr) < 0) {
close(tac_fd);
_pam_log(LOG_ERR, "error sending auth req to TACACS+ server");
continue;
}
communicating = 1;
while (communicating) {
msg = tac_authen_read(tac_fd);
/* 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");
status = PAM_SUCCESS;
communicating = 0;
active_server.addr = tac_srv[srv_i].addr;
active_server.key = tac_srv[srv_i].key;
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "%s: active srv %d", __FUNCTION__, srv_i);
break;
case TAC_PLUS_AUTHEN_STATUS_FAIL:
/* forget it */
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "tacacs status: TAC_PLUS_AUTHEN_STATUS_FAIL");
status = PAM_AUTH_ERR;
communicating = 0;
_pam_log(LOG_ERR, "auth failed: %d", msg);
break;
case TAC_PLUS_AUTHEN_STATUS_GETDATA:
/* not implemented */
if (ctrl & PAM_TAC_DEBUG)
syslog(LOG_DEBUG, "tacacs status: TAC_PLUS_AUTHEN_STATUS_GETDATA");
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");
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;
break;
}
/* 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");
/*
* not implemented
* WdJ: I *think* you can just do tac_authen_send(user, pass) again
* but I'm not sure
*/
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");
communicating = 0;
break;
default:
if (msg < 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", msg);
}
} /* 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);
bzero(pass, strlen (pass));
free(pass);
pass = NULL;
return status;
} /* pam_sm_authenticate */
/* 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;
int srv_i;
int tac_fd;
int status = PAM_AUTH_ERR;
user = pass = tty = r_addr = NULL;
ctrl = _pam_parse (argc, argv);
if (ctrl & PAM_TAC_DEBUG)
syslog (LOG_DEBUG, "%s: called (pam_tacplus v%u.%u.%u)"
, __FUNCTION__, PAM_TAC_VMAJ, PAM_TAC_VMIN, PAM_TAC_VPAT);
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);
/* uwzgledniac PAM_DISALLOW_NULL_AUTHTOK */
retval = tacacs_get_password (pamh, flags, ctrl, &pass);
if (retval != PAM_SUCCESS || pass == NULL || *pass == '\0') {
_pam_log (LOG_ERR, "unable to obtain password");
return PAM_CRED_INSUFFICIENT;
}
retval = pam_set_item (pamh, PAM_AUTHTOK, pass);
if (retval != PAM_SUCCESS) {
_pam_log (LOG_ERR, "unable to set password");
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/", 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);
for (srv_i = 0; srv_i < tac_srv_no; srv_i++) {
int msg = TAC_PLUS_AUTHEN_STATUS_FAIL;
if (ctrl & PAM_TAC_DEBUG)
syslog (LOG_DEBUG, "%s: trying srv %d", __FUNCTION__, srv_i );
tac_fd = tac_connect_single(tac_srv[srv_i], tac_srv_key[srv_i]);
if (tac_fd < 0) {
_pam_log (LOG_ERR, "connection failed srv %d: %m", srv_i);
if (srv_i == tac_srv_no-1) {
_pam_log (LOG_ERR, "no more servers to connect");
return PAM_AUTHINFO_UNAVAIL;
}
continue;
}
if (tac_authen_send(tac_fd, user, pass, tty, r_addr) < 0) {
_pam_log (LOG_ERR, "error sending auth req to TACACS+ server");
status = PAM_AUTHINFO_UNAVAIL;
} else {
msg = tac_authen_read(tac_fd);
if (msg == 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");
status = PAM_AUTHINFO_UNAVAIL;
} else {
msg = tac_authen_read(tac_fd);
if (msg != TAC_PLUS_AUTHEN_STATUS_PASS) {
_pam_log (LOG_ERR, "auth failed: %d", msg);
status = PAM_AUTH_ERR;
} else {
/* OK, we got authenticated; save the server that
accepted us for pam_sm_acct_mgmt and exit the loop */
status = PAM_SUCCESS;
active_server = tac_srv[srv_i];
active_key = tac_srv_key[srv_i];
close(tac_fd);
break;
}
}
} else if (msg != TAC_PLUS_AUTHEN_STATUS_PASS) {
_pam_log (LOG_ERR, "auth failed: %d", msg);
status = PAM_AUTH_ERR;
} else {
/* OK, we got authenticated; save the server that
accepted us for pam_sm_acct_mgmt and exit the loop */
status = PAM_SUCCESS;
active_server = tac_srv[srv_i];
active_key = tac_srv_key[srv_i];
close(tac_fd);
break;
}
}
close(tac_fd);
}
if (ctrl & PAM_TAC_DEBUG)
syslog (LOG_DEBUG, "%s: exit with pam status: %i", __FUNCTION__, status);
bzero (pass, strlen (pass));
free(pass);
pass = NULL;
return status;
} /* pam_sm_authenticate */