espressif/esp_wifi_remote

readme

# esp_wifi_remote

[![Component Registry](https://components.espressif.com/components/espressif/esp_wifi_remote/badge.svg)](https://components.espressif.com/components/espressif/esp_wifi_remote)

The `esp_wifi_remote` component is designed to extend WiFi functionality to ESP chipsets that lack native WiFi support. By simply adding a dependency to this component from your project, you gain access to WiFi capabilities via the WiFi-remote menuconfig and standard `esp_wifi` interface.

Moreover, `esp_wifi_remote` can be utilized on ESP chipsets that do support native WiFi, providing an additional WiFi interface through the `esp_wifi_remote` API.

To employ this component, a slave device -- capable of WiFi connectivity -- must be connected to your target device in a specified manner, as defined by the transport layer of [`esp_hosted`](https://github.com/espressif/esp-hosted).

Functionally, `esp_wifi_remote` wraps the public API of `esp_wifi`, offering a set of function call namespaces prefixed with esp_wifi_remote. These calls are translated into Remote Procedure Calls (RPC) to another target device (referred to as the "slave" device), which then executes the appropriate `esp_wifi` APIs.

Notably, `esp_wifi_remote` heavily relies on a specific version of the `esp_wifi` component. Consequently, the majority of its headers, sources, and configuration files are pre-generated based on the actual version of `esp_wifi`.

It's important to highlight that `esp_wifi_remote` does not directly implement the RPC calls; rather, it relies on dependencies for this functionality. Presently, only esp_hosted is supported to provide the RPC functionality required by esp_wifi_remote.


## Dependencies on `esp_wifi`

Public API needs to correspond exactly to the `esp_wifi` API. Some of the internal types depend on the actual wifi target, as well as some default configuration values. Therefore it's easier to maintain consistency between this component and the exact version of `esp_wifi` automatically in CI:

* We extract function prototypes from `esp_wifi.h` and use them to generate `esp_wifi_remote` function declarations.
* We process the local `esp_wifi_types_native.h` and replace `CONFIG_IDF_TARGET` to `CONFIG_SLAVE_IDF_TARGET` and `CONFIG_SOC_WIFI_...` to `CONFIG_SLAVE_....`
* Similarly we process `esp_wifi`'s Kconfig, so the dependencies are on the slave target and slave SOC capabilities.

Please check the [README.md](./scripts/README.md) for more details on the generation step and testing consistency.

changelog

# Changelog

## [0.2.0](https://github.com/espressif/esp-protocols/commits/wifi_remote-v0.2.0)

### Features

- Add support for simple eppp based RPC ([fd168d8](https://github.com/espressif/esp-protocols/commit/fd168d8))

### Bug Fixes

- Make services restartable, code cleanup ([6c82ce2](https://github.com/espressif/esp-protocols/commit/6c82ce2))
- Add examples to CI ([d2b7c55](https://github.com/espressif/esp-protocols/commit/d2b7c55))

## [0.1.12](https://github.com/espressif/esp-protocols/commits/wifi_remote-v0.1.12)

### Features

- Added generation step for wifi_remote based on IDF ([dfb00358](https://github.com/espressif/esp-protocols/commit/dfb00358))
- Move to esp-protocols ([edc3c2d](https://github.com/espressif/esp-protocols/commit/edc3c2d))

                                        
                                        # MQTT application running on WiFi station

This is a simple mqtt demo, that connects to WiFi AP first. This application has a dependency to `esp_wifi_remote`, so that if it's build and executed on a chipset without WiFI capabilities it redirects all wifi calls the remote target.

## Overview

When running this example on a target that doesn't natively support WiFi, please make sure that the remote target (slave application) is connected to your chipset via the configured transport interface.

Connection to the slave device also depends on RPC library used. It is recommended to use [`esp_hosted`](https://github.com/espressif/esp-hosted). Alternatively you can use [`eppp_link`](https://components.espressif.com/components/espressif/eppp_link).

Please note, that `esp_hosted` as a component is currently WIP, so the `wifi_remote` defaults to `eppp`, for now.

## HW connection

We currently support only `UART` transport, so the connection is very simple. You only need to connect Rx, Tx and GND with the remote target.
You need to configure these fields according to your connection:
* CONFIG_ESP_WIFI_REMOTE_EPPP_UART_TX_PIN
* CONFIG_ESP_WIFI_REMOTE_EPPP_UART_RX_PIN

## SW configuration

The RPC mechanism between the host and the slave micro uses TLS with mutual authentication, so you would have to configure certificates and keys for both parties. This application -- host target -- is considered RPC client, so it needs client's certificate and key, as well as the CA certificate to validate the server (slave application).
If self-signed certificates are acceptable, you can use [generate_test_certs](../test_certs/generate_test_certs.sh) script to generate both the CA and the keys itself and convert them to the PEM format that's accepted by the EPPP RPC engine.
You will have to configure these options:
* CONFIG_ESP_WIFI_REMOTE_EPPP_SERVER_CA
* CONFIG_ESP_WIFI_REMOTE_EPPP_CLIENT_CRT
* CONFIG_ESP_WIFI_REMOTE_EPPP_CLIENT_KEY

## Setting up slave device

You need to set up the connection and configuration in a similar way on the slave part (connection pins + certificates and keys). Please refer to the [slave_application](../server/README.md) README for more information.

                                    

                                        
                                        # WiFi remote EPPP RPC server

This is a standalone application serving as the slave device for `esp_wifi_remote` users (with `eppp` RPC).

## Overview

You need to configure and connect a slave device to the `esp_wifi_remote` host and run this application. Please fallow carefully these guidelines on HW connection and configuration of the slave device, based on the host device.

## HW connection

We currently support only `UART` transport you just need to connect Rx, Tx and GND and configure these fields accordingly:
* CONFIG_ESP_WIFI_REMOTE_EPPP_UART_TX_PIN
* CONFIG_ESP_WIFI_REMOTE_EPPP_UART_RX_PIN

## SW configuration

You will have to install server side certificates and keys, as well as the CA which should verify the client side.
Please configure these options:
* CONFIG_ESP_WIFI_REMOTE_EPPP_CLIENT_CA
* CONFIG_ESP_WIFI_REMOTE_EPPP_SERVER_CRT
* CONFIG_ESP_WIFI_REMOTE_EPPP_SERVER_KEY