afb-auth: export method to check a single permission
[src/app-framework-binder.git] / src / afb-auth.c
1 /*
2  * Copyright (C) 2016, 2017 "IoT.bzh"
3  * Author "Fulup Ar Foll"
4  * Author José Bollo <jose.bollo@iot.bzh>
5  *
6  * Licensed under the Apache License, Version 2.0 (the "License");
7  * you may not use this file except in compliance with the License.
8  * You may obtain a copy of the License at
9  *
10  *   http://www.apache.org/licenses/LICENSE-2.0
11  *
12  * Unless required by applicable law or agreed to in writing, software
13  * distributed under the License is distributed on an "AS IS" BASIS,
14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15  * See the License for the specific language governing permissions and
16  * limitations under the License.
17  */
18
19 #define _GNU_SOURCE
20 #define AFB_BINDING_PRAGMA_NO_VERBOSE_MACRO
21
22 #include <stdlib.h>
23
24 #include <afb/afb-auth.h>
25
26 #include "afb-auth.h"
27 #include "afb-context.h"
28 #include "afb-xreq.h"
29 #include "afb-cred.h"
30 #include "verbose.h"
31
32 int afb_auth_check(struct afb_xreq *xreq, const struct afb_auth *auth)
33 {
34         switch (auth->type) {
35         default:
36         case afb_auth_No:
37                 return 0;
38
39         case afb_auth_Token:
40                 return afb_context_check(&xreq->context);
41
42         case afb_auth_LOA:
43                 return afb_context_check_loa(&xreq->context, auth->loa);
44
45         case afb_auth_Permission:
46                 if (xreq->cred && auth->text)
47                         return afb_auth_check_permission(xreq, auth->text);
48                 /* TODO: handle case of self permission */
49                 return 1;
50
51         case afb_auth_Or:
52                 return afb_auth_check(xreq, auth->first) || afb_auth_check(xreq, auth->next);
53
54         case afb_auth_And:
55                 return afb_auth_check(xreq, auth->first) && afb_auth_check(xreq, auth->next);
56
57         case afb_auth_Not:
58                 return !afb_auth_check(xreq, auth->first);
59
60         case afb_auth_Yes:
61                 return 1;
62         }
63 }
64
65 /*********************************************************************************/
66 #ifdef BACKEND_PERMISSION_IS_CYNARA
67
68 #include <pthread.h>
69 #include <cynara-client.h>
70
71 static cynara *handle;
72 static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
73
74 int afb_auth_check_permission(struct afb_xreq *xreq, const char *permission)
75 {
76         int rc;
77
78         /* cynara isn't reentrant */
79         pthread_mutex_lock(&mutex);
80
81         /* lazy initialisation */
82         if (!handle) {
83                 rc = cynara_initialize(&handle, NULL);
84                 if (rc != CYNARA_API_SUCCESS) {
85                         handle = NULL;
86                         ERROR("cynara initialisation failed with code %d", rc);
87                         return 0;
88                 }
89         }
90
91         /* query cynara permission */
92         rc = cynara_check(handle, xreq->cred->label, afb_context_uuid(&xreq->context), xreq->cred->user, permission);
93
94         pthread_mutex_unlock(&mutex);
95         return rc == CYNARA_API_ACCESS_ALLOWED;
96 }
97
98 /*********************************************************************************/
99 #else
100 int afb_auth_check_permission(struct afb_xreq *xreq, const char *permission)
101 {
102         WARNING("Granting permission %s by default of backend", permission);
103         return 1;
104 }
105 #endif
106