Protocol Communication (protocomm) component manages secure sessions and provides framework for multiple transports. The application can also use protocomm layer directly to have application specific extensions for the provisioning (or non-provisioning) use cases.
Following features are available for provisioning :
* Proof-of-possession (support with protocomm_security1 only)
Protocomm internally uses protobuf (protocol buffers) for secure session establishment. Though users can implement their own security (even without using protobuf). One can even use protocomm without any security layer.
Protocomm provides framework for various transports - WiFi (SoftAP+HTTPD), BLE, console - in which case the handler invocation is automatically taken care of on the device side (see Transport Examples below for code snippets).
Note that the client still needs to establish session (only for protocomm_security1) by performing the two way handshake. See :doc:`provisioning` for more details about the secure handshake logic.
Transport Example (SoftAP + HTTP) with Security 1
-------------------------------------------------
For complete example see :example:`provisioning/softap_prov`
..highlight:: c
::
/* Endpoint handler to be registered with protocomm.
* This simply echoes back the received data. */
esp_err_t echo_req_handler (uint32_t session_id,
const uint8_t *inbuf, ssize_t inlen,
uint8_t **outbuf, ssize_t *outlen,
void *priv_data)
{
/* Session ID may be used for persistence */
printf("Session ID : %d", session_id);
/* Echo back the received data */
*outlen = inlen; /* Output data length updated */
*outbuf = malloc(inlen); /* This will be deallocated outside */
memcpy(*outbuf, inbuf, inlen);
/* Private data that was passed at the time of endpoint creation */
uint32_t *priv = (uint32_t *) priv_data;
if (priv) {
printf("Private data : %d", *priv);
}
return ESP_OK;
}
/* Example function for launching a protocomm instance over HTTP */
