-Binding Reference
-=================
+# Binding Reference
-Structure for declaring binding
--------------------------------
+## Structure for declaring binding
-### struct afb_binding_v2
+### afb_binding_t
-The main structure, of type **afb_binding_v2**, for describing the binding
-must be exported under the name **afbBindingV2**.
+The main structure, of type **afb_binding_t**, for describing the binding
+must be exported under the name **afbBindingExport**.
This structure is defined as below.
```C
-/*
- * Description of the bindings of type version 2
+typedef struct afb_binding_v3 afb_binding_t;
+```
+
+Where:
+
+```C
+/**
+ * Description of the bindings of type version 3
*/
-struct afb_binding_v2
+struct afb_binding_v3
{
- const char *api; /* api name for the binding */
- const char *specification; /* textual openAPIv3 specification of the binding */
- const struct afb_verb_v2 *verbs; /* array of descriptions of verbs terminated by a NULL name */
- int (*preinit)(); /* callback at load of the binding */
- int (*init)(); /* callback for starting the service */
- void (*onevent)(const char *event, struct json_object *object); /* callback for handling events */
- unsigned noconcurrency: 1; /* avoids concurrent requests to verbs */
+ /** api name for the binding, can't be NULL */
+ const char *api;
+
+ /** textual specification of the binding, can be NULL */
+ const char *specification;
+
+ /** some info about the api, can be NULL */
+ const char *info;
+
+ /** array of descriptions of verbs terminated by a NULL name, can be NULL */
+ const struct afb_verb_v3 *verbs;
+
+ /** callback at load of the binding */
+ int (*preinit)(struct afb_api_x3 *api);
+
+ /** callback for starting the service */
+ int (*init)(struct afb_api_x3 *api);
+
+ /** callback for handling events */
+ void (*onevent)(struct afb_api_x3 *api, const char *event, struct json_object *object);
+
+ /** userdata for afb_api_x3 */
+ void *userdata;
+
+ /** space separated list of provided class(es) */
+ const char *provide_class;
+
+ /** space separated list of required class(es) */
+ const char *require_class;
+
+ /** space separated list of required API(es) */
+ const char *require_api;
+
+ /** avoids concurrent requests to verbs */
+ unsigned noconcurrency: 1;
};
```
-### struct afb_verb_v2
+### struct afb_verb_t
-Each verb is described with a structure of type **afb_verb_v2**
+Each verb is described with a structure of type **afb_verb_t**
defined below:
```C
-/*
- * Description of one verb of the API provided by the binding
- * This enumeration is valid for bindings of type version 2
+typedef struct afb_verb_v3 afb_verb_t;
+```
+
+```C
+/**
+ * Description of one verb as provided for binding API version 3
*/
-struct afb_verb_v2
+struct afb_verb_v3
{
- const char *verb; /* name of the verb */
- void (*callback)(struct afb_req req); /* callback function implementing the verb */
- const struct afb_auth *auth; /* required authorization */
- uint32_t session; /* authorization and session requirements of the verb */
+ /** name of the verb, NULL only at end of the array */
+ const char *verb;
+
+ /** callback function implementing the verb */
+ void (*callback)(afb_req_t_x2 *req);
+
+ /** required authorization, can be NULL */
+ const struct afb_auth *auth;
+
+ /** some info about the verb, can be NULL */
+ const char *info;
+
+ /**< data for the verb callback */
+ void *vcbdata;
+
+ /** authorization and session requirements of the verb */
+ uint16_t session;
+
+ /** is the verb glob name */
+ uint16_t glob: 1;
};
```
-The session flags is an or of the constant defined below:
+The **session** flags is one of the constant defined below:
- - AFB_SESSION_NONE : no flag, synonym to 0
- - AFB_SESSION_LOA_0 : Requires the LOA to be 0 or more, synonym to 0 or AFB_SESSION_NONE
- - AFB_SESSION_LOA_1 : Requires the LOA to be 1 or more
- - AFB_SESSION_LOA_2 : Requires the LOA to be 2 or more
- - AFB_SESSION_LOA_3 : Requires the LOA to be 3 or more
- - AFB_SESSION_CHECK : Requires the token to be set and valid
- - AFB_SESSION_REFRESH : Implies a token refresh
- - AFB_SESSION_CLOSE : Implies cloing the session
+- AFB_SESSION_NONE : no flag, synonym to 0
+- AFB_SESSION_LOA_0 : Requires the LOA to be 0 or more, synonym to 0 or AFB_SESSION_NONE
+- AFB_SESSION_LOA_1 : Requires the LOA to be 1 or more
+- AFB_SESSION_LOA_2 : Requires the LOA to be 2 or more
+- AFB_SESSION_LOA_3 : Requires the LOA to be 3 or more
+- AFB_SESSION_CHECK : Requires the token to be set and valid
+- AFB_SESSION_REFRESH : Implies a token refresh
+- AFB_SESSION_CLOSE : Implies closing the session after request processed
-The LOA is set binding by binding using the function **afb_req_session_set_LOA**.
+The LOA (Level Of Assurance) is set, by binding api, using the function **afb_req_session_set_LOA**.
-### struct afb_auth and enum afb_auth_type
+The session can be closed, by binding api, using the function **afb_req_session_close**.
-The structure **afb_auth** is used within verb description to
-set security requirements. The interpretation of the structure
-depends on the value of the field **type**.
+### afb_auth_t and afb_auth_type_t
+
+The structure **afb_auth_t** is used within verb description to
+set security requirements.
+The interpretation of the structure depends on the value of the field **type**.
```C
+typedef struct afb_auth afb_auth_t;
+
+/**
+ * Definition of an authorization entry
+ */
struct afb_auth
{
- const enum afb_auth_type type;
- union {
- const char *text;
- const unsigned loa;
- const struct afb_auth *first;
- };
- const struct afb_auth *next;
+ /** type of entry @see afb_auth_type */
+ enum afb_auth_type type;
+
+ union {
+ /** text when @ref type == @ref afb_auth_Permission */
+ const char *text;
+
+ /** level of assurancy when @ref type == @ref afb_auth_LOA */
+ unsigned loa;
+
+ /** first child when @ref type in { @ref afb_auth_Or, @ref afb_auth_And, @ref afb_auth_Not } */
+ const struct afb_auth *first;
+ };
+
+ /** second child when @ref type in { @ref afb_auth_Or, @ref afb_auth_And } */
+ const struct afb_auth *next;
};
+
```
+
The possible values for **type** is defined here:
```C
-/*
- * Enum for Session/Token/Assurance middleware.
+typedef enum afb_auth_type afb_auth_type_t;
+
+/**
+ * Enumeration for authority (Session/Token/Assurance) definitions.
+ *
+ * @see afb_auth
*/
enum afb_auth_type
{
- afb_auth_No = 0, /** never authorized, no data */
- afb_auth_Token, /** authorized if token valid, no data */
- afb_auth_LOA, /** authorized if LOA greater than data 'loa' */
- afb_auth_Permission, /** authorized if permission 'text' is granted */
- afb_auth_Or, /** authorized if 'first' or 'next' is authorized */
- afb_auth_And, /** authorized if 'first' and 'next' are authorized */
- afb_auth_Not, /** authorized if 'first' is not authorized */
- afb_auth_Yes /** always authorized, no data */
+ /** never authorized, no data */
+ afb_auth_No = 0,
+
+ /** authorized if token valid, no data */
+ afb_auth_Token,
+
+ /** authorized if LOA greater than data 'loa' */
+ afb_auth_LOA,
+
+ /** authorized if permission 'text' is granted */
+ afb_auth_Permission,
+
+ /** authorized if 'first' or 'next' is authorized */
+ afb_auth_Or,
+
+ /** authorized if 'first' and 'next' are authorized */
+ afb_auth_And,
+
+ /** authorized if 'first' is not authorized */
+ afb_auth_Not,
+
+ /** always authorized, no data */
+ afb_auth_Yes
};
```
Example:
```C
-static const struct afb_auth _afb_auths_v2_monitor[] = {
- { .type = afb_auth_Permission, .text = "urn:AGL:permission:monitor:public:set" },
- { .type = afb_auth_Permission, .text = "urn:AGL:permission:monitor:public:get" },
- { .type = afb_auth_Or, .first = &_afb_auths_v2_monitor[1], .next = &_afb_auths_v2_monitor[0] }
+static const afb_auth_t myauth[] = {
+ { .type = afb_auth_Permission, .text = "urn:AGL:permission:me:public:set" },
+ { .type = afb_auth_Permission, .text = "urn:AGL:permission:me:public:get" },
+ { .type = afb_auth_Or, .first = &myauth[1], .next = &myauth[0] }
};
```
-Functions of class afb_daemon...
--------------------------
+## Functions of class afb_daemon
-The 3 following functions are linked to libsystemd.
+The 3 following functions are linked to libsystemd.
They allow use of **sd_event** features and access
to **sd_bus** features.
```C
/*
- * Retrieves the common systemd's event loop of AFB
+ * Retrieves the common systemd's event loop of AFB
+ *
*/
struct sd_event *afb_daemon_get_event_loop();
/*
- * Retrieves the common systemd's user/session d-bus of AFB
+ * Retrieves the common systemd's user/session d-bus of AFB if active
*/
struct sd_bus *afb_daemon_get_user_bus();
/*
- * Retrieves the common systemd's system d-bus of AFB
+ * Retrieves the common systemd's system d-bus of AFB if active or NULL
*/
struct sd_bus *afb_daemon_get_system_bus();
```
-The 2 following functions are linked to event management.
+The 2 following functions are linked to event management.
Broadcasting an event send it to any possible listener.
```C
* Thus, in the case where 'object' should remain available after
* the function returns, the function 'json_object_get' shall be used.
*
+ * Calling this function is only forbidden during preinit.
+ *
* Returns the count of clients that received the event.
*/
int afb_daemon_broadcast_event(const char *name, struct json_object *object);
/*
* Creates an event of 'name' and returns it.
*
+ * Calling this function is only forbidden during preinit.
+ *
* See afb_event_is_valid to check if there is an error.
*/
-struct afb_event afb_daemon_make_event(const char *name);
+afb_event_t afb_daemon_make_event(const char *name);
```
The following function is used by logging macros and should normally
-not be used. Instead, you should use the macros
-**AFB\_ERROR**, **AFB\_WARNING**, **AFB\_NOTICE**,
-**AFB\_INFO**, **AFB\_DEBUG**
+not be used.
+Instead, you should use the macros:
+
+- **AFB\_ERROR**
+- **AFB\_WARNING**
+- **AFB\_NOTICE**
+- **AFB\_INFO**
+- **AFB\_DEBUG**
```C
/*
/*
* Tells that it requires the API of "name" to exist
* and if 'initialized' is not null to be initialized.
+ * Calling this function is only allowed within init.
* Returns 0 in case of success or -1 in case of error.
*/
int afb_daemon_require_api(const char *name, int initialized)
```
-Functions of class afb_service...
--------------------------
+This function allows to give a different name to the binding.
+It can be called during pre-init.
+
+```C
+/*
+ * Set the name of the API to 'name'.
+ * Calling this function is only allowed within preinit.
+ * Returns 0 in case of success or -1 in case of error.
+ */
+int afb_daemon_rename_api(const char *name);
+```
+
+## Functions of class afb_service
The following functions allow services to call verbs of other
bindings for themselves.
* @see also 'afb_req_subcall'
*/
void afb_service_call(
- const char *api,
- const char *verb,
- struct json_object *args,
- void (*callback)(void*closure, int status, struct json_object *result),
- void *callback_closure);
+ const char *api,
+ const char *verb,
+ struct json_object *args,
+ void (*callback)(void*closure, int status, struct json_object *result),
+ void *callback_closure);
/**
* Calls the 'verb' of the 'api' with the arguments 'args' and 'verb' in the name of the binding.
* @see also 'afb_req_subcall'
*/
int afb_service_call_sync(
- const char *api,
- const char *verb,
- struct json_object *args,
- struct json_object **result);
+ const char *api,
+ const char *verb,
+ struct json_object *args,
+ struct json_object **result);
```
-Functions of class afb_event...
--------------------------
+## Functions of class afb_event
-This function checks whether the event is valid. It must be used
-when creating events.
+This function checks whether the event is valid.
+It must be used when creating events.
```C
/*
*
* Returns 0 if not valid or 1 if valid.
*/
-int afb_event_is_valid(struct afb_event event);
+int afb_event_is_valid(afb_event_t event);
```
The two following functions are used to broadcast or push
*
* Returns the count of clients that received the event.
*/
-int afb_event_broadcast(struct afb_event event, struct json_object *object);
+int afb_event_broadcast(afb_event_t event, struct json_object *object);
/*
* Pushes the 'event' with the data 'object' to its observers.
*
* Returns the count of clients that received the event.
*/
-int afb_event_push(struct afb_event event, struct json_object *object);
+int afb_event_push(afb_event_t event, struct json_object *object);
```
-The following function destiys the event.
+The following function remove one reference to the event.
```C
/*
- * Drops the data associated to the 'event'
+ * Decrease the reference count of the event.
* After calling this function, the event
* MUST NOT BE USED ANYMORE.
*/
-void afb_event_drop(struct afb_event event);
+void afb_event_unref(afb_event_t event);
+```
+
+The following function add one reference to the event.
+
+```C
+/*
+ * Decrease the reference count of the event.
+ * After calling this function, the event
+ * MUST NOT BE USED ANYMORE.
+ */
+void afb_event_unref(afb_event_t event);
```
This function allows to retrieve the exact name of the event.
/*
* Gets the name associated to the 'event'.
*/
-const char *afb_event_name(struct afb_event event);
+const char *afb_event_name(afb_event_t event);
```
-Functions of class afb_req...
--------------------------
+## Functions of class afb_req
This function checks the validity of the **req**.
*
* Returns 0 if not valid or 1 if valid.
*/
-int afb_req_is_valid(struct afb_req req);
+int afb_req_is_valid(afb_req_t req);
```
The following functions retrieves parameters of the request.
* an HTTP POST of Content-Type "application/json". In that case, the
* argument of name "" receives the value of the body of the HTTP request.
*/
-struct afb_arg afb_req_get(struct afb_req req, const char *name);
+afb_arg_t afb_req_get(afb_req_t req, const char *name);
/*
* Gets from the request 'req' the string value of the argument of 'name'.
*
* Shortcut for: afb_req_get(req, name).value
*/
-const char *afb_req_value(struct afb_req req, const char *name);
+const char *afb_req_value(afb_req_t req, const char *name);
/*
* Gets from the request 'req' the path for file attached to the argument of 'name'.
*
* Shortcut for: afb_req_get(req, name).path
*/
-const char *afb_req_path(struct afb_req req, const char *name);
+const char *afb_req_path(afb_req_t req, const char *name);
/*
* Gets from the request 'req' the json object hashing the arguments.
* The returned object must not be released using 'json_object_put'.
*/
-struct json_object *afb_req_json(struct afb_req req);
+struct json_object *afb_req_json(afb_req_t req);
```
The following functions emit the reply to the request.
* Thus, in the case where 'obj' should remain available after
* the function returns, the function 'json_object_get' shall be used.
*/
-void afb_req_success(struct afb_req req, struct json_object *obj, const char *info);
+void afb_req_success(afb_req_t req, struct json_object *obj, const char *info);
/*
* Same as 'afb_req_success' but the 'info' is a formatting
* Thus, in the case where 'obj' should remain available after
* the function returns, the function 'json_object_get' shall be used.
*/
-void afb_req_success_f(struct afb_req req, struct json_object *obj, const char *info, ...);
+void afb_req_success_f(afb_req_t req, struct json_object *obj, const char *info, ...);
/*
* Same as 'afb_req_success_f' but the arguments to the format 'info'
* Thus, in the case where 'obj' should remain available after
* the function returns, the function 'json_object_get' shall be used.
*/
-void afb_req_success_v(struct afb_req req, struct json_object *obj, const char *info, va_list args);
+void afb_req_success_v(afb_req_t req, struct json_object *obj, const char *info, va_list args);
/*
* Sends a reply of kind failure to the request 'req'.
* The status of the reply is set to 'status' and an
- * informationnal comment 'info' (can also be NULL) can be added.
+ * informational comment 'info' (can also be NULL) can be added.
*
* Note that calling afb_req_fail("success", info) is equivalent
* to call afb_req_success(NULL, info). Thus even if possible it
* is strongly recommended to NEVER use "success" for status.
*/
-void afb_req_fail(struct afb_req req, const char *status, const char *info);
+void afb_req_fail(afb_req_t req, const char *status, const char *info);
/*
* Same as 'afb_req_fail' but the 'info' is a formatting
* string followed by arguments.
*/
-void afb_req_fail_f(struct afb_req req, const char *status, const char *info, ...);
+void afb_req_fail_f(afb_req_t req, const char *status, const char *info, ...);
/*
* Same as 'afb_req_fail_f' but the arguments to the format 'info'
* are given as a variable argument list instance.
*/
-void afb_req_fail_v(struct afb_req req, const char *status, const char *info, va_list args);
+void afb_req_fail_v(afb_req_t req, const char *status, const char *info, va_list args);
```
The following functions handle the session data.
* Gets the pointer stored by the binding for the session of 'req'.
* When the binding has not yet recorded a pointer, NULL is returned.
*/
-void *afb_req_context_get(struct afb_req req);
+void *afb_req_context_get(afb_req_t req);
/*
* Stores for the binding the pointer 'context' to the session of 'req'.
* The function 'free_context' will be called when the session is closed
* or if binding stores an other pointer.
*/
-void afb_req_context_set(struct afb_req req, void *context, void (*free_context)(void*));
+void afb_req_context_set(afb_req_t req, void *context, void (*free_context)(void*));
/*
* Gets the pointer stored by the binding for the session of 'req'.
* the function 'create_context' and stores it with the freeing function
* 'free_context'.
*/
-void *afb_req_context(struct afb_req req, void *(*create_context)(), void (*free_context)(void*));
+void *afb_req_context(afb_req_t req, void *(*create_context)(), void (*free_context)(void*));
/*
* Frees the pointer stored by the binding for the session of 'req'
*
* Shortcut for: afb_req_context_set(req, NULL, NULL)
*/
-void afb_req_context_clear(struct afb_req req);
+void afb_req_context_clear(afb_req_t req);
/*
* Closes the session associated with 'req'
* and delete all associated contexts.
*/
-void afb_req_session_close(struct afb_req req);
+void afb_req_session_close(afb_req_t req);
/*
* Sets the level of assurance of the session of 'req'
* security policies.
* Returns 1 on success or 0 if failed.
*/
-int afb_req_session_set_LOA(struct afb_req req, unsigned level);
+int afb_req_session_set_LOA(afb_req_t req, unsigned level);
```
-
The 4 following functions must be used for asynchronous handling requests.
```C
* This function MUST be called by asynchronous implementations
* of verbs if no reply was sent before returning.
*/
-void afb_req_addref(struct afb_req req);
+void afb_req_addref(afb_req_t req);
/*
* Substracts one to the count of references of 'req'.
* This function MUST be called by asynchronous implementations
* of verbs after sending the asynchronous reply.
*/
-void afb_req_unref(struct afb_req req);
+void afb_req_unref(afb_req_t req);
/*
* Stores 'req' on heap for asynchronous use.
* The count of reference to 'req' is incremented on success
* (see afb_req_addref).
*/
-struct afb_stored_req *afb_req_store(struct afb_req req);
+struct afb_stored_req *afb_req_store(afb_req_t req);
/*
* Retrieves the afb_req stored at 'sreq'.
* function 'afb_req_unref' should be called on the result
* after that the asynchronous reply if sent.
*/
-struct afb_req afb_req_unstore(struct afb_stored_req *sreq);
+afb_req_t afb_req_unstore(struct afb_stored_req *sreq);
```
The two following functions are used to associate client with events
* to the 'event'.
* Returns 0 in case of successful subscription or -1 in case of error.
*/
-int afb_req_subscribe(struct afb_req req, struct afb_event event);
+int afb_req_subscribe(afb_req_t req, afb_event_t event);
/*
* Revokes the subscription established to the 'event' for the client
* link identified by 'req'.
* Returns 0 in case of successful subscription or -1 in case of error.
*/
-int afb_req_unsubscribe(struct afb_req req, struct afb_event event);
+int afb_req_unsubscribe(afb_req_t req, afb_event_t event);
```
The following functions must be used to make request in the name of the
* For convenience, the function calls 'json_object_put' for 'args'.
* Thus, in the case where 'args' should remain available after
* the function returns, the function 'json_object_get' shall be used.
+ *
+ * See also:
+ * - 'afb_req_subcall_req' that is convenient to keep request alive automatically.
+ * - 'afb_req_subcall_sync' the synchronous version
*/
void afb_req_subcall(
- struct afb_req req,
+ afb_req_t req,
const char *api,
const char *verb,
struct json_object *args,
void (*callback)(void *closure, int status, struct json_object *result),
void *closure);
+/*
+ * Makes a call to the method of name 'api' / 'verb' with the object 'args'.
+ * This call is made in the context of the request 'req'.
+ * On completion, the function 'callback' is invoked with the
+ * original request 'req', the 'closure' given at call and two
+ * other parameters: 'iserror' and 'result'.
+ * 'status' is 0 on success or negative when on an error reply.
+ * 'result' is the json object of the reply, you must not call json_object_put
+ * on the result.
+ *
+ * For convenience, the function calls 'json_object_put' for 'args'.
+ * Thus, in the case where 'args' should remain available after
+ * the function returns, the function 'json_object_get' shall be used.
+ *
+ * See also:
+ * - 'afb_req_subcall' that doesn't keep request alive automatically.
+ * - 'afb_req_subcall_sync' the synchronous version
+ */
+static inline void afb_req_subcall_req(afb_req_t req, const char *api, const char *verb, struct json_object *args, void (*callback)(void *closure, int iserror, struct json_object *result, afb_req_t req), void *closure)
+{
+ req.itf->subcall_req(req.closure, api, verb, args, callback, closure);
+}
+
/*
* Makes a call to the method of name 'api' / 'verb' with the object 'args'.
* This call is made in the context of the request 'req'.
* For convenience, the function calls 'json_object_put' for 'args'.
* Thus, in the case where 'args' should remain available after
* the function returns, the function 'json_object_get' shall be used.
+ *
+ * See also:
+ * - 'afb_req_subcall_req' that is convenient to keep request alive automatically.
+ * - 'afb_req_subcall' that doesn't keep request alive automatically.
*/
int afb_req_subcall_sync(
- struct afb_req req,
+ afb_req_t req,
const char *api,
const char *verb,
struct json_object *args,
```
The following function is used by logging macros and should normally
-not be used. Instead, you should use the macros
-**AFB_REQ_ERROR**, **AFB_REQ_WARNING**, **AFB_REQ_NOTICE**,
-**AFB_REQ_INFO**, **AFB_REQ_DEBUG**
+not be used.
+Instead, you should use the macros:
+
+- **AFB_REQ_ERROR**
+- **AFB_REQ_WARNING**
+- **AFB_REQ_NOTICE**
+- **AFB_REQ_INFO**
+- **AFB_REQ_DEBUG**
```C
/*
* INFO 6 Informational
* DEBUG 7 Debug-level messages
*/
-void afb_req_verbose(struct afb_req req, int level, const char *file, int line, const char * func, const char *fmt, ...);
+void afb_req_verbose(afb_req_t req, int level, const char *file, int line, const char * func, const char *fmt, ...);
+```
+
+The functions below allow a binding involved in the platform security
+to explicitely check a permission of a client or to get the calling
+application identity.
+
+```C
+/*
+ * Check whether the 'permission' is granted or not to the client
+ * identified by 'req'.
+ *
+ * Returns 1 if the permission is granted or 0 otherwise.
+ */
+int afb_req_has_permission(afb_req_t req, const char *permission);
+
+/*
+ * Get the application identifier of the client application for the
+ * request 'req'.
+ *
+ * Returns the application identifier or NULL when the application
+ * can not be identified.
+ *
+ * The returned value if not NULL must be freed by the caller
+ */
+char *afb_req_get_application_id(afb_req_t req);
+
+/*
+ * Get the user identifier (UID) of the client application for the
+ * request 'req'.
+ *
+ * Returns -1 when the application can not be identified.
+ */
+int afb_req_get_uid(afb_req_t req);
```
-Logging macros
---------------
+## Logging macros
The following macros must be used for logging:
Code Review / src / app-framework-binder.git / blobdiff