/*
Authors:
Pavel Březina <pbrezina@redhat.com>
Copyright (C) 2016 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 <tevent.h>
#include <talloc.h>
#include "util/util.h"
#include "util/sss_ptr_hash.h"
#include "responder/nss/nss_private.h"
typedef errno_t (*nss_setent_set_timeout_fn)(struct tevent_context *ev,
struct nss_ctx *nss_ctx,
struct nss_enum_ctx *enum_ctx);
struct nss_setent_internal_state {
struct tevent_context *ev;
struct nss_ctx *nss_ctx;
struct nss_enum_ctx *enum_ctx;
nss_setent_set_timeout_fn timeout_handler;
enum cache_req_type type;
};
static void nss_setent_internal_done(struct tevent_req *subreq);
/* Cache request data is stealed on internal state. */
static struct tevent_req *
nss_setent_internal_send(TALLOC_CTX *mem_ctx,
struct tevent_context *ev,
struct cli_ctx *cli_ctx,
struct cache_req_data *data,
enum cache_req_type type,
struct nss_enum_ctx *enum_ctx,
nss_setent_set_timeout_fn timeout_handler)
{
struct nss_setent_internal_state *state;
struct tevent_req *subreq;
struct tevent_req *req;
errno_t ret;
req = tevent_req_create(mem_ctx, &state, struct nss_setent_internal_state);
if (req == NULL) {
DEBUG(SSSDBG_CRIT_FAILURE, "Unable to create tevent request!\n");
return NULL;
}
talloc_steal(state, data);
state->ev = ev;
state->nss_ctx = talloc_get_type(cli_ctx->rctx->pvt_ctx, struct nss_ctx);
state->enum_ctx = enum_ctx;
state->type = type;
state->timeout_handler = timeout_handler;
if (state->enum_ctx->is_ready) {
/* Object is already constructed, just return here. */
talloc_free(data);
ret = EOK;
goto done;
}
if (state->enum_ctx->ongoing != NULL) {
/* Object is being constructed. Register ourselves for
* notification when it is finished. */
ret = setent_add_ref(state, &state->enum_ctx->notify_list, req);
if (ret != EOK) {
DEBUG(SSSDBG_CRIT_FAILURE,
"Unable to register setent reference [%d]: %s!\n",
ret, sss_strerror(ret));
goto done;
}
ret = EAGAIN;
goto done;
}
/* Create new object. */
state->enum_ctx->is_ready = false;
subreq = cache_req_send(req, ev, cli_ctx->rctx, cli_ctx->rctx->ncache,
0, CACHE_REQ_POSIX_DOM, NULL, data);
if (subreq == NULL) {
DEBUG(SSSDBG_CRIT_FAILURE, "Unable to send cache request!\n");
ret = ENOMEM;
goto done;
}
tevent_req_set_callback(subreq, nss_setent_internal_done, req);
state->enum_ctx->ongoing = subreq;
ret = EAGAIN;
done:
if (ret == EOK) {
tevent_req_done(req);
tevent_req_post(req, ev);
} else if (ret != EAGAIN) {
tevent_req_error(req, ret);
tevent_req_post(req, ev);
}
return req;
}
static void nss_setent_internal_done(struct tevent_req *subreq)
{
struct cache_req_result **result;
struct nss_setent_internal_state *state;
struct setent_req_list **notify_list;
struct tevent_req *req;
errno_t ret;
errno_t tret;
req = tevent_req_callback_data(subreq, struct tevent_req);
state = tevent_req_data(req, struct nss_setent_internal_state);
/* This is the ongoing request and it is finished. Remove it. */
state->enum_ctx->ongoing = NULL;
ret = cache_req_recv(state, subreq, &result);
talloc_zfree(subreq);
switch (ret) {
case EOK:
talloc_zfree(state->enum_ctx->result);
state->enum_ctx->result = talloc_steal(state->nss_ctx, result);
if (state->type == CACHE_REQ_NETGROUP_BY_NAME) {
/* We need to expand the netgroup into triples and members. */
ret = sysdb_netgr_to_entries(state->enum_ctx,
result[0]->ldb_result,
&state->enum_ctx->netgroup,
&state->enum_ctx->netgroup_count);
if (ret != EOK) {
goto done;
}
}
break;
case ENOENT:
/* Reset the result but build it again next time setent is called. */
talloc_zfree(state->enum_ctx->result);
talloc_zfree(state->enum_ctx->netgroup);
goto done;
default:
/* In case of an error, we do not touch the enumeration context. */
goto done;
}
/* Expire the result object after its timeout is reached. */
tret = state->timeout_handler(state->ev, state->nss_ctx, state->enum_ctx);
if (tret != EOK) {
ret = ENOMEM;
goto done;
}
/* The object is ready now. */
state->enum_ctx->is_ready = true;
ret = EOK;
done:
/* We want to finish the requests in correct order, this was the
* first request, notify_list contain the subsequent request.
*
* Because callback invoked from tevent_req_done will free state,
* we must remember notify_list explicitly to avoid segfault.
*/
notify_list = &state->enum_ctx->notify_list;
if (ret == EOK) {
tevent_req_done(req);
setent_notify_done(notify_list);
} else {
tevent_req_error(req, ret);
setent_notify(notify_list, ret);
}
}
static errno_t
nss_setent_internal_recv(struct tevent_req *req)
{
TEVENT_REQ_RETURN_ON_ERROR(req);
return EOK;
}
static void
nss_setent_timeout(struct tevent_context *ev,
struct tevent_timer *te,
struct timeval current_time,
void *pvt)
{
struct nss_enum_ctx *enum_ctx = pvt;
DEBUG(SSSDBG_TRACE_FUNC, "Enumeration result object has expired.\n");
/* Reset enumeration context. */
talloc_zfree(enum_ctx->result);
enum_ctx->is_ready = false;
}
static errno_t
nss_setent_set_timeout(struct tevent_context *ev,
struct nss_ctx *nss_ctx,
struct nss_enum_ctx *enum_ctx)
{
struct tevent_timer *te;
struct timeval tv;
tv = tevent_timeval_current_ofs(nss_ctx->enum_cache_timeout, 0);
te = tevent_add_timer(ev, nss_ctx, tv, nss_setent_timeout, enum_ctx);
if (te == NULL) {
DEBUG(SSSDBG_CRIT_FAILURE,
"Could not set up life timer for enumeration object.\n");
return ENOMEM;
}
return EOK;
}
struct tevent_req *
nss_setent_send(TALLOC_CTX *mem_ctx,
struct tevent_context *ev,
struct cli_ctx *cli_ctx,
enum cache_req_type type,
struct nss_enum_ctx *enum_ctx)
{
struct cache_req_data *data;
data = cache_req_data_enum(mem_ctx, type);
if (data == NULL) {
DEBUG(SSSDBG_CRIT_FAILURE, "Unable to set cache request data!\n");
return NULL;
}
return nss_setent_internal_send(mem_ctx, ev, cli_ctx, data, type, enum_ctx,
nss_setent_set_timeout);
}
errno_t nss_setent_recv(struct tevent_req *req)
{
return nss_setent_internal_recv(req);
}
static void
nss_setnetgrent_timeout(struct tevent_context *ev,
struct tevent_timer *te,
struct timeval current_time,
void *pvt)
{
struct nss_enum_ctx *enum_ctx;
DEBUG(SSSDBG_TRACE_FUNC, "Enumeration result object has expired.\n");
/* Free enumeration context. This will also remove it from the table. */
enum_ctx = talloc_get_type(pvt, struct nss_enum_ctx);
talloc_free(enum_ctx);
}
static errno_t
nss_setnetgrent_set_timeout(struct tevent_context *ev,
struct nss_ctx *nss_ctx,
struct nss_enum_ctx *enum_ctx)
{
struct tevent_timer *te;
struct timeval tv;
uint32_t timeout;
if (nss_ctx->cache_refresh_percent) {
timeout = enum_ctx->result[0]->domain->netgroup_timeout *
(nss_ctx->cache_refresh_percent / 100.0);
} else {
timeout = enum_ctx->result[0]->domain->netgroup_timeout;
}
/* In order to not trash the cache between setnetgrent()/getnetgrent()
* calls with too low timeout values, we only allow 10 seconds as
* the minimal timeout
*/
if (timeout < 10) timeout = 10;
tv = tevent_timeval_current_ofs(timeout, 0);
te = tevent_add_timer(ev, enum_ctx, tv, nss_setnetgrent_timeout, enum_ctx);
if (te == NULL) {
DEBUG(SSSDBG_CRIT_FAILURE,
"Could not set up life timer for enumeration object.\n");
return ENOMEM;
}
return EOK;
}
static struct nss_enum_ctx *
nss_setnetgrent_set_enum_ctx(hash_table_t *table,
const char *netgroup)
{
struct nss_enum_ctx *enum_ctx;
errno_t ret;
enum_ctx = sss_ptr_hash_lookup(table, netgroup, struct nss_enum_ctx);
if (enum_ctx != NULL) {
return enum_ctx;
}
enum_ctx = talloc_zero(table, struct nss_enum_ctx);
if (enum_ctx == NULL) {
return NULL;
}
ret = sss_ptr_hash_add(table, netgroup, enum_ctx, struct nss_enum_ctx);
if (ret != EOK) {
DEBUG(SSSDBG_CRIT_FAILURE,
"Unable to add enumeration context into table [%d]: %s\n",
ret, sss_strerror(ret));
talloc_free(enum_ctx);
return NULL;
}
return enum_ctx;
}
struct tevent_req *
nss_setnetgrent_send(TALLOC_CTX *mem_ctx,
struct tevent_context *ev,
struct cli_ctx *cli_ctx,
enum cache_req_type type,
hash_table_t *table,
const char *netgroup)
{
struct nss_enum_ctx *enum_ctx;
struct cache_req_data *data;
enum_ctx = nss_setnetgrent_set_enum_ctx(table, netgroup);
if (enum_ctx == NULL) {
return NULL;
}
data = cache_req_data_name(mem_ctx, type, netgroup);
if (data == NULL) {
return NULL;
}
return nss_setent_internal_send(mem_ctx, ev, cli_ctx, data, type, enum_ctx,
nss_setnetgrent_set_timeout);
}
errno_t nss_setnetgrent_recv(struct tevent_req *req)
{
return nss_setent_internal_recv(req);
}