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/* This code is originated from pam_passthru plugin of 389-ds,
* thus its copyright statement is introduced below: */
/** BEGIN COPYRIGHT BLOCK
* 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; version 2 of the License.
*
* 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; if not, write to the Free Software Foundation, Inc., 59 Temple
* Place, Suite 330, Boston, MA 02111-1307 USA.
*
* In addition, as a special exception, Red Hat, Inc. gives You the additional
* right to link the code of this Program with code not covered under the GNU
* General Public License ("Non-GPL Code") and to distribute linked combinations
* including the two, subject to the limitations in this paragraph. Non-GPL Code
* permitted under this exception must only link to the code of this Program
* through those well defined interfaces identified in the file named EXCEPTION
* found in the source code files (the "Approved Interfaces"). The files of
* Non-GPL Code may instantiate templates or use macros or inline functions from
* the Approved Interfaces without causing the resulting work to be covered by
* the GNU General Public License. Only Red Hat, Inc. may make changes or
* additions to the list of Approved Interfaces. You must obey the GNU General
* Public License in all respects for all of the Program code and other code used
* in conjunction with the Program except the Non-GPL Code covered by this
* exception. If you modify this file, you may extend this exception to your
* version of the file, but you are not obligated to do so. If you do not wish to
* provide this exception without modification, you must delete this exception
* statement from your version and license this file solely under the GPL without
* exception.
*
*
* Copyright (C) 2005 Red Hat, Inc.
* All rights reserved.
* END COPYRIGHT BLOCK **/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <sys/types.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#ifdef HAVE_DIRSRV_SLAPI_PLUGIN_H
#include <nspr.h>
#include <nss.h>
#include <dirsrv/slapi-plugin.h>
#else
#include <slapi-plugin.h>
#endif
#include <security/pam_appl.h>
/* for third arg to pam_start */
struct my_pam_conv_str {
Slapi_PBlock *pb;
const char *pam_identity;
};
static void
free_pam_response(int nresp, struct pam_response *resp)
{
int ii;
for (ii = 0; ii < nresp; ++ii) {
if (resp[ii].resp) {
free(resp[ii].resp);
}
}
free(resp);
}
/*
* This is the conversation function passed into pam_start(). This is what sets the password
* that PAM uses to authenticate. This function is sort of stupid - it assumes all echo off
* or binary prompts are for the password, and other prompts are for the username. Time will
* tell if this is actually the case.
*/
static int
pam_conv_func(int num_msg, const struct pam_message **msg, struct pam_response **resp, void *mydata)
{
int ii;
struct berval *creds;
struct my_pam_conv_str *my_data = (struct my_pam_conv_str *)mydata;
struct pam_response *reply;
int ret = PAM_SUCCESS;
if (num_msg <= 0) {
return PAM_CONV_ERR;
}
/* empty reply structure. We have to use malloc/free due to the caller freeing the response */
reply = (struct pam_response *) calloc(num_msg, sizeof(struct pam_response));
slapi_pblock_get(my_data->pb, SLAPI_BIND_CREDENTIALS, &creds); /* the password */
for (ii = 0; ii < num_msg; ++ii) {
/* hard to tell what prompt is for . . . */
/* assume prompts for password are either BINARY or ECHO_OFF */
switch (msg[ii]->msg_style) {
case PAM_PROMPT_ECHO_OFF:
#ifdef LINUX
case PAM_BINARY_PROMPT:
#endif
reply[ii].resp = malloc(creds->bv_len + 1);
if (reply[ii].resp != NULL) {
memcpy(reply[ii].resp, creds->bv_val, creds->bv_len);
reply[ii].resp[creds->bv_len] = '\0';
} else {
ret = PAM_CONV_ERR;
}
break;
case PAM_PROMPT_ECHO_ON:
reply[ii].resp = strdup(my_data->pam_identity);
if (reply[ii].resp == NULL) {
ret = PAM_CONV_ERR;
}
break;
case PAM_ERROR_MSG:
case PAM_TEXT_INFO:
break;
default:
ret = PAM_CONV_ERR;
break;
}
}
if (ret == PAM_CONV_ERR) {
free_pam_response(num_msg, reply);
reply = NULL;
}
*resp = reply;
return ret;
}
/*
* Do the actual work of authenticating with PAM.
* Set up the structures that pam_start needs and call pam_start(). After
* that, call pam_authenticate and pam_acct_mgmt. Check the various return
* values from these functions and map them to their corresponding LDAP BIND
* return values. Return the appropriate LDAP error code.
* This function will also set the appropriate LDAP response controls in
* the given pblock.
*/
static int
do_pam_auth(Slapi_PBlock *pb, const char *pam_service, /* name of service for pam_start() */
int pw_response_requested, /* do we need to send pwd policy resp control */
const char *username)
{
const char *binddn = NULL;
Slapi_DN *bindsdn = NULL;
int rc = PAM_SUCCESS;
int retcode = LDAP_SUCCESS;
pam_handle_t *pam_handle;
struct my_pam_conv_str my_data;
struct pam_conv my_pam_conv = {pam_conv_func, NULL};
char *errmsg = NULL; /* free with PR_smprintf_free */
slapi_pblock_get(pb, SLAPI_BIND_TARGET_SDN, &bindsdn);
if (NULL == bindsdn) {
errmsg = PR_smprintf("Null bind dn");
retcode = LDAP_OPERATIONS_ERROR;
goto done; /* skip the pam stuff */
}
binddn = slapi_sdn_get_dn(bindsdn);
/* do the pam stuff */
my_data.pb = pb;
my_data.pam_identity = username;
my_pam_conv.appdata_ptr = &my_data;
rc = pam_start(pam_service, username, &my_pam_conv, &pam_handle);
if (rc == PAM_SUCCESS) {
/* use PAM_SILENT - there is no user interaction at this point */
rc = pam_authenticate(pam_handle, 0);
/* check different types of errors here */
switch (rc) {
case PAM_USER_UNKNOWN:
errmsg = PR_smprintf("User id [%s] for bind DN [%s] does not exist in PAM",
username, binddn);
retcode = LDAP_NO_SUCH_OBJECT; /* user unknown */
break;
case PAM_AUTH_ERR:
errmsg = PR_smprintf("Invalid PAM password for user id [%s], bind DN [%s]",
username, binddn);
retcode = LDAP_INVALID_CREDENTIALS; /* invalid creds */
break;
case PAM_MAXTRIES:
errmsg = PR_smprintf("Authentication retry limit exceeded in PAM for "
"user id [%s], bind DN [%s]", username, binddn);
if (pw_response_requested) {
slapi_pwpolicy_make_response_control(pb, -1, -1, LDAP_PWPOLICY_ACCTLOCKED);
}
retcode = LDAP_CONSTRAINT_VIOLATION; /* max retries */
break;
case PAM_SUCCESS:
break;
default:
errmsg = PR_smprintf("Unknown PAM error [%s] for user id [%s], bind DN [%s]",
pam_strerror(pam_handle, rc), username, binddn);
retcode = LDAP_OPERATIONS_ERROR; /* pam config or network problem */
break;
}
}
/* if user authenticated successfully, see if there is anything we need
to report back w.r.t. password or account lockout */
if (rc == PAM_SUCCESS) {
rc = pam_acct_mgmt(pam_handle, 0);
/* check different types of errors here */
switch (rc) {
case PAM_USER_UNKNOWN:
errmsg = PR_smprintf("User id [%s] for bind DN [%s] does not exist in PAM",
username, binddn);
retcode = LDAP_NO_SUCH_OBJECT; /* user unknown */
break;
case PAM_AUTH_ERR:
errmsg = PR_smprintf("Invalid PAM password for user id [%s], bind DN [%s]",
username, binddn);
retcode = LDAP_INVALID_CREDENTIALS; /* invalid creds */
break;
case PAM_PERM_DENIED:
errmsg = PR_smprintf("Access denied for PAM user id [%s], bind DN [%s]"
" - see administrator", username, binddn);
if (pw_response_requested) {
slapi_pwpolicy_make_response_control(pb, -1, -1, LDAP_PWPOLICY_ACCTLOCKED);
}
retcode = LDAP_UNWILLING_TO_PERFORM;
break;
case PAM_ACCT_EXPIRED:
case PAM_NEW_AUTHTOK_REQD:
errmsg = PR_smprintf("Expired PAM password for user id [%s], bind DN [%s]: "
"reset required", username, binddn);
slapi_add_pwd_control(pb, LDAP_CONTROL_PWEXPIRED, 0);
if (pw_response_requested) {
slapi_pwpolicy_make_response_control(pb, -1, -1, LDAP_PWPOLICY_PWDEXPIRED);
}
retcode = LDAP_INVALID_CREDENTIALS;
break;
case PAM_SUCCESS:
break;
default:
errmsg = PR_smprintf("Unknown PAM error [%s] for user id [%s], bind DN [%s]",
pam_strerror(pam_handle, rc), username, binddn);
retcode = LDAP_OPERATIONS_ERROR; /* unknown */
break;
}
}
rc = pam_end(pam_handle, rc);
done:
if ((retcode == LDAP_SUCCESS) && (rc != PAM_SUCCESS)) {
errmsg = PR_smprintf("Unknown PAM error [%d] for user id [%s], bind DN [%s]",
rc, username, binddn);
retcode = LDAP_OPERATIONS_ERROR;
}
if (retcode != LDAP_SUCCESS) {
slapi_send_ldap_result(pb, retcode, NULL, errmsg, 0, NULL);
}
if (errmsg) {
PR_smprintf_free(errmsg);
}
return retcode;
}
int
backend_sch_do_pam_auth(Slapi_PBlock *pb, const char *username)
{
int rc = LDAP_SUCCESS;
int pw_response_requested;
LDAPControl **reqctrls = NULL;
slapi_pblock_get (pb, SLAPI_REQCONTROLS, &reqctrls);
slapi_pblock_get (pb, SLAPI_PWPOLICY, &pw_response_requested);
rc = do_pam_auth(pb, "system-auth", pw_response_requested, username);
return rc;
}
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