DP: Introduce new interface for backend

Terminology:
* Backend: Implemenation of domain
* Data Provider: interface between backend and responders
* Module: ldap/ipa/ad/... dlopened library that implements dp interface
* Target: id/autofs/sudo/... functionality of module

Benefits over current code:
* data provider is a black box completely separated from backend
* method handlers are just simple tevent requests on backend side
* no need of spy on be_client
* simplified and error proof adding of new responders
* simplified adding of new methods
* reply to D-Bus message is completely handled by DP code
* each target can have several methods defined
* properties can be added on objects
* each method can have output parameters
* modules now support constructor
* improved debugging
* clear memory hierarchy
* ability to chain requests
* type safe private data

Reviewed-by: Sumit Bose <sbose@redhat.com>
Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>
Reviewed-by: Lukáš Slebodník <lslebodn@redhat.com>

1 files changed, 118 insertions, 0 deletions

diff --git a/src/providers/data_provider/dp_builtin.c b/src/providers/data_provider/dp_builtin.c
new file mode 100644
index 000000000..01d7f6deb
--- /dev/null
+++ b/src/providers/data_provider/dp_builtin.c
@@ -0,0 +1,118 @@
+/*
+    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 <security/pam_modules.h>
+#include <talloc.h>
+#include "config.h"
+#include "providers/data_provider/dp.h"
+#include "providers/backend.h"
+#include "util/util.h"
+
+struct dp_access_permit_handler_state {
+    struct pam_data *pd;
+};
+
+struct tevent_req *
+dp_access_permit_handler_send(TALLOC_CTX *mem_ctx,
+                              void *data,
+                              struct pam_data *pd,
+                              struct dp_req_params *params)
+{
+    struct dp_access_permit_handler_state *state;
+    struct tevent_req *req;
+
+    req = tevent_req_create(mem_ctx, &state,
+                            struct dp_access_permit_handler_state);
+    if (req == NULL) {
+        DEBUG(SSSDBG_CRIT_FAILURE, "tevent_req_create() failed\n");
+        return NULL;
+    }
+
+    state->pd = pd;
+    DEBUG(SSSDBG_TRACE_ALL, "Access permit, returning PAM_SUCCESS.\n");
+    state->pd->pam_status = PAM_SUCCESS;
+
+    tevent_req_done(req);
+    tevent_req_post(req, params->ev);
+
+    return req;
+}
+
+errno_t
+dp_access_permit_handler_recv(TALLOC_CTX *mem_ctx,
+                              struct tevent_req *req,
+                              struct pam_data **_data)
+{
+    struct dp_access_permit_handler_state *state = NULL;
+
+    state = tevent_req_data(req, struct dp_access_permit_handler_state);
+
+    TEVENT_REQ_RETURN_ON_ERROR(req);
+
+    *_data = talloc_steal(mem_ctx, state->pd);
+
+    return EOK;
+}
+
+struct dp_access_deny_handler_state {
+    struct pam_data *pd;
+};
+
+struct tevent_req *
+dp_access_deny_handler_send(TALLOC_CTX *mem_ctx,
+                            void *data,
+                            struct pam_data *pd,
+                            struct dp_req_params *params)
+{
+    struct dp_access_deny_handler_state *state;
+    struct tevent_req *req;
+
+    req = tevent_req_create(mem_ctx, &state,
+                            struct dp_access_deny_handler_state);
+    if (req == NULL) {
+        DEBUG(SSSDBG_CRIT_FAILURE, "tevent_req_create() failed\n");
+        return NULL;
+    }
+
+    state->pd = pd;
+    DEBUG(SSSDBG_TRACE_ALL, "Access deny, returning PAM_PERM_DENIED.\n");
+    state->pd->pam_status = PAM_PERM_DENIED;
+
+    tevent_req_done(req);
+    tevent_req_post(req, params->ev);
+
+    return req;
+}
+
+errno_t
+dp_access_deny_handler_recv(TALLOC_CTX *mem_ctx,
+                            struct tevent_req *req,
+                            struct pam_data **_data)
+{
+    struct dp_access_deny_handler_state *state = NULL;
+
+    state = tevent_req_data(req, struct dp_access_deny_handler_state);
+
+    TEVENT_REQ_RETURN_ON_ERROR(req);
+
+    *_data = talloc_steal(mem_ctx, state->pd);
+
+    return EOK;
+}