/*
SSSD
Kerberos 5 Backend Module - access control
Authors:
Sumit Bose <sbose@redhat.com>
Copyright (C) 2010 Red Hat
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 3 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. If not, see <http://www.gnu.org/licenses/>.
*/
#include "util/util.h"
#include "providers/krb5/krb5_auth.h"
#include "providers/krb5/krb5_common.h"
#include "providers/krb5/krb5_utils.h"
struct krb5_access_state {
struct tevent_context *ev;
struct be_ctx *be_ctx;
struct pam_data *pd;
struct krb5_ctx *krb5_ctx;
struct krb5child_req *kr;
bool access_allowed;
};
static void krb5_access_done(struct tevent_req *subreq);
struct tevent_req *krb5_access_send(TALLOC_CTX *mem_ctx,
struct tevent_context *ev,
struct be_ctx *be_ctx,
struct pam_data *pd,
struct krb5_ctx *krb5_ctx)
{
struct krb5_access_state *state;
struct tevent_req *req;
struct tevent_req *subreq;
int ret;
const char **attrs;
struct ldb_result *res;
struct sss_domain_info *dom;
req = tevent_req_create(mem_ctx, &state, struct krb5_access_state);
if (req == NULL) {
DEBUG(SSSDBG_CRIT_FAILURE, "tevent_req_create failed.\n");
return NULL;
}
state->ev = ev;
state->be_ctx = be_ctx;
state->pd = pd;
state->krb5_ctx = krb5_ctx;
state->access_allowed = false;
ret = get_domain_or_subdomain(be_ctx, pd->domain, &dom);
if (ret != EOK) {
DEBUG(SSSDBG_OP_FAILURE, "get_domain_or_subdomain failed.\n");
goto done;
}
ret = krb5_setup(state, pd, dom, krb5_ctx, &state->kr);
if (ret != EOK) {
DEBUG(SSSDBG_CRIT_FAILURE, "krb5_setup failed.\n");
goto done;
}
if (pd->cmd != SSS_PAM_ACCT_MGMT) {
DEBUG(SSSDBG_CRIT_FAILURE, "Unexpected pam task.\n");
ret = EINVAL;
goto done;
}
attrs = talloc_array(state, const char *, 5);
if (attrs == NULL) {
DEBUG(SSSDBG_CRIT_FAILURE, "talloc_array failed.\n");
ret = ENOMEM;
goto done;
}
attrs[0] = SYSDB_UPN;
attrs[1] = SYSDB_UIDNUM;
attrs[2] = SYSDB_GIDNUM;
attrs[3] = SYSDB_CANONICAL_UPN;
attrs[4] = NULL;
ret = sysdb_get_user_attr(state, be_ctx->domain, state->pd->user, attrs,
&res);
if (ret) {
DEBUG(SSSDBG_FUNC_DATA,
"sysdb search for upn of user [%s] failed.\n", pd->user);
goto done;
}
switch (res->count) {
case 0:
DEBUG(SSSDBG_FUNC_DATA,
"No attributes for user [%s] found.\n", pd->user);
ret = ENOENT;
goto done;
break;
case 1:
ret = find_or_guess_upn(state, res->msgs[0], krb5_ctx, be_ctx->domain,
state->kr->user, pd->domain, &state->kr->upn);
if (ret != EOK) {
DEBUG(SSSDBG_OP_FAILURE, "find_or_guess_upn failed.\n");
goto done;
}
state->kr->uid = ldb_msg_find_attr_as_uint64(res->msgs[0], SYSDB_UIDNUM,
0);
if (state->kr->uid == 0) {
DEBUG(SSSDBG_CONF_SETTINGS,
"UID for user [%s] not known.\n", pd->user);
ret = ENOENT;
goto done;
}
state->kr->gid = ldb_msg_find_attr_as_uint64(res->msgs[0], SYSDB_GIDNUM,
0);
if (state->kr->gid == 0) {
DEBUG(SSSDBG_CONF_SETTINGS,
"GID for user [%s] not known.\n", pd->user);
ret = ENOENT;
goto done;
}
break;
default:
DEBUG(SSSDBG_CRIT_FAILURE,
"User search for [%s] returned > 1 results!\n", pd->user);
ret = EINVAL;
goto done;
break;
}
subreq = handle_child_send(state, state->ev, state->kr);
if (subreq == NULL) {
DEBUG(SSSDBG_CRIT_FAILURE, "handle_child_send failed.\n");
ret = ENOMEM;
goto done;
}
tevent_req_set_callback(subreq, krb5_access_done, req);
return req;
done:
if (ret == EOK) {
tevent_req_done(req);
} else {
tevent_req_error(req, ret);
}
tevent_req_post(req, state->ev);
return req;
}
static void krb5_access_done(struct tevent_req *subreq)
{
struct tevent_req *req = tevent_req_callback_data(subreq, struct tevent_req);
struct krb5_access_state *state = tevent_req_data(req,
struct krb5_access_state);
int ret;
uint8_t *buf = NULL;
ssize_t len = -1;
int32_t msg_status;
ret = handle_child_recv(subreq, state, &buf, &len);
talloc_free(subreq);
if (ret != EOK) {
DEBUG(SSSDBG_CRIT_FAILURE,
"child failed [%d][%s].\n", ret, strerror(ret));
goto fail;
}
if ((size_t) len != sizeof(int32_t)) {
DEBUG(SSSDBG_CRIT_FAILURE, "message has the wrong size.\n");
ret = EINVAL;
goto fail;
}
SAFEALIGN_COPY_INT32(&msg_status, buf, NULL);
if (msg_status == EOK) {
state->access_allowed = true;
} else {
state->access_allowed = false;
}
tevent_req_done(req);
return;
fail:
tevent_req_error(req, ret);
return;
}
int krb5_access_recv(struct tevent_req *req, bool *access_allowed)
{
struct krb5_access_state *state = tevent_req_data(req,
struct krb5_access_state);
TEVENT_REQ_RETURN_ON_ERROR(req);
*access_allowed = state->access_allowed;
return EOK;
}