OVMS3-idf/components/protocomm/include/common/protocomm.h
Amey Inamdar d0c777b2e1 Protocomm : Added component core for protocol communication
* This manages secure sessions and provides framework for multiple transports.
* The application can use protocomm layer directly to have application specific extensions for provisioning (or non-provisioning) use cases.
* Following features are available for provisioning :

  * Security - Security0 (no security), Security1 (curve25519 key exchange + AES-CTR encryption)
  * Proof-of-possession support for Security1

* Protocomm requires specific protocol buffer modules for compilation which can be generated from the `.proto` files in the `proto` directory using make.

Co-Authored-By: Amey Inamdar <amey@espressif.com>
Co-Authored-By: Anurag Kar <anurag.kar@espressif.com>
2018-10-02 19:07:28 +05:30

226 lines
8.8 KiB
C

// Copyright 2018 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#pragma once
#include <protocomm_security.h>
#include <esp_err.h>
/**
* @brief Function prototype for protocomm endpoint handler
*/
typedef esp_err_t (*protocomm_req_handler_t)(
uint32_t session_id, /*!< Session ID for identifying protocomm client */
const uint8_t *inbuf, /*!< Pointer to user provided input data buffer */
ssize_t inlen, /*!< Length o the input buffer */
uint8_t **outbuf, /*!< Pointer to output buffer allocated by handler */
ssize_t *outlen, /*!< Length of the allocated output buffer */
void *priv_data /*!< Private data passed to the handler (NULL if not used) */
);
/**
* @brief This structure corresponds to a unique instance of protocomm
* returned when the API `protocomm_new()` is called. The remaining
* Protocomm APIs require this object as the first parameter.
*
* @note Structure of the protocomm object is kept private
*/
typedef struct protocomm protocomm_t;
/**
* @brief Create a new protocomm instance
*
* This API will return a new dynamically allocated protocomm instance
* with all elements of the protocomm_t structure initialised to NULL.
*
* @return
* - protocomm_t* : On success
* - NULL : No memory for allocating new instance
*/
protocomm_t *protocomm_new();
/**
* @brief Delete a protocomm instance
*
* This API will deallocate a protocomm instance that was created
* using `protocomm_new()`.
*
* @param[in] pc Pointer to the protocomm instance to be deleted
*/
void protocomm_delete(protocomm_t *pc);
/**
* @brief Add endpoint request handler for a protocomm instance
*
* This API will bind an endpoint handler function to the specified
* endpoint name, along with any private data that needs to be pass to
* the handler at the time of call.
*
* @note
* - An endpoint must be bound to a valid protocomm instance,
* created using `protocomm_new()`.
* - This function internally calls the registered `add_endpoint()`
* function which is a member of the protocomm_t instance structure.
*
* @param[in] pc Pointer to the protocomm instance
* @param[in] ep_name Endpoint identifier(name) string
* @param[in] h Endpoint handler function
* @param[in] priv_data Pointer to private data to be passed as a
* parameter to the handler function on call.
* Pass NULL if not needed.
*
* @return
* - ESP_OK : Added new endpoint succesfully
* - ESP_FAIL : Error adding endpoint / Endpoint with this name already exists
* - ESP_ERR_NO_MEM : Error allocating endpoint resource
* - ESP_ERR_INVALID_ARG : Null instance/name/handler arguments
*/
esp_err_t protocomm_add_endpoint(protocomm_t *pc, const char *ep_name,
protocomm_req_handler_t h, void *priv_data);
/**
* @brief Remove endpoint request handler for a protocomm instance
*
* This API will remove a registered endpoint handler identified by
* an endpoint name.
*
* @note
* - This function internally calls the registered `remove_endpoint()`
* function which is a member of the protocomm_t instance structure.
*
* @param[in] pc Pointer to the protocomm instance
* @param[in] ep_name Endpoint identifier(name) string
*
* @return
* - ESP_OK : Added new endpoint succesfully
* - ESP_ERR_NOT_FOUND : Endpoint with specified name doesn't exist
* - ESP_ERR_INVALID_ARG : Null instance/name arguments
*/
esp_err_t protocomm_remove_endpoint(protocomm_t *pc, const char *ep_name);
/**
* @brief Calls the registered handler of an endpoint session
* for processing incoming data and giving the output
*
* @note
* - An endpoint must be bound to a valid protocomm instance,
* created using `protocomm_new()`.
* - Resulting output buffer must be deallocated by the user.
*
* @param[in] pc Pointer to the protocomm instance
* @param[in] ep_name Endpoint identifier(name) string
* @param[in] session_id Unique ID for a communication session
* @param[in] inbuf Input buffer contains input request data which is to be
* processed by the registered handler
* @param[in] inlen Length of the input buffer
* @param[out] outbuf Pointer to internally allocated output buffer,
* where the resulting response data output from
* the registered handler is to be stored
* @param[out] outlen Buffer length of the allocated output buffer
*
* @return
* - ESP_OK : Request handled succesfully
* - ESP_FAIL : Internal error in execution of registered handler
* - ESP_ERR_NO_MEM : Error allocating internal resource
* - ESP_ERR_NOT_FOUND : Endpoint with specified name doesn't exist
* - ESP_ERR_INVALID_ARG : Null instance/name arguments
*/
esp_err_t protocomm_req_handle(protocomm_t *pc, const char *ep_name, uint32_t session_id,
const uint8_t *inbuf, ssize_t inlen,
uint8_t **outbuf, ssize_t *outlen);
/**
* @brief Add endpoint security for a protocomm instance
*
* This API will bind a security session establisher to the specified
* endpoint name, along with any proof of possession that may be required
* for authenticating a session client.
*
* @note
* - An endpoint must be bound to a valid protocomm instance,
* created using `protocomm_new()`.
* - The choice of security can be any `protocomm_security_t` instance.
* Choices `protocomm_security0` and `protocomm_security1` are readily available.
*
* @param[in] pc Pointer to the protocomm instance
* @param[in] ep_name Endpoint identifier(name) string
* @param[in] sec Pointer to endpoint security instance
* @param[in] pop Pointer to proof of possession for authenticating a client
*
* @return
* - ESP_OK : Added new security endpoint succesfully
* - ESP_FAIL : Error adding endpoint / Endpoint with this name already exists
* - ESP_ERR_INVALID_STATE : Security endpoint already set
* - ESP_ERR_NO_MEM : Error allocating endpoint resource
* - ESP_ERR_INVALID_ARG : Null instance/name/handler arguments
*/
esp_err_t protocomm_set_security(protocomm_t *pc, const char *ep_name,
const protocomm_security_t *sec,
const protocomm_security_pop_t *pop);
/**
* @brief Remove endpoint security for a protocomm instance
*
* This API will remove a registered security endpoint identified by
* an endpoint name.
*
* @param[in] pc Pointer to the protocomm instance
* @param[in] ep_name Endpoint identifier(name) string
*
* @return
* - ESP_OK : Added new endpoint succesfully
* - ESP_ERR_NOT_FOUND : Endpoint with specified name doesn't exist
* - ESP_ERR_INVALID_ARG : Null instance/name arguments
*/
esp_err_t protocomm_unset_security(protocomm_t *pc, const char *ep_name);
/**
* @brief Set endpoint for version verification
*
* This API can be used for setting an application specific protocol
* version which can be verfied by clients through the endpoint.
*
* @note
* - An endpoint must be bound to a valid protocomm instance,
* created using `protocomm_new()`.
* @param[in] pc Pointer to the protocomm instance
* @param[in] ep_name Endpoint identifier(name) string
* @param[in] version Version identifier(name) string
*
* @return
* - ESP_OK : Added new security endpoint succesfully
* - ESP_FAIL : Error adding endpoint / Endpoint with this name already exists
* - ESP_ERR_INVALID_STATE : Version endpoint already set
* - ESP_ERR_NO_MEM : Error allocating endpoint resource
* - ESP_ERR_INVALID_ARG : Null instance/name/handler arguments
*/
esp_err_t protocomm_set_version(protocomm_t *pc, const char *ep_name,
const char *version);
/**
* @brief Remove version verification endpoint from a protocomm instance
*
* This API will remove a registered version endpoint identified by
* an endpoint name.
*
* @param[in] pc Pointer to the protocomm instance
* @param[in] ep_name Endpoint identifier(name) string
*
* @return
* - ESP_OK : Added new endpoint succesfully
* - ESP_ERR_NOT_FOUND : Endpoint with specified name doesn't exist
* - ESP_ERR_INVALID_ARG : Null instance/name arguments
*/
esp_err_t protocomm_unset_version(protocomm_t *pc, const char *ep_name);