sneha3821/rdk-wifi-hal

Purpose and Build Surface

rdk-wifi-hal is a native C/C++ Wi-Fi Hardware Abstraction Layer implementing Wi-Fi control state machines and packet processing, including EasyConnect/DPP and Passpoint/ANQP. Autotools is the primary build integration, rooted at configure.ac, Makefile.am, and src/Makefile.am.

HAL Core and Public/Private Boundary

The central HAL implementation exposes RDK-oriented Wi-Fi operations while maintaining internal state and framework contracts. src/wifi_hal.c is the core implementation; src/wifi_hal_rdk.h and src/wifi_hal_rdk_framework.h define HAL/framework-facing interfaces; src/wifi_hal_priv.h holds internal shared definitions. Platform code is expected to supply hardware-specific behavior beneath this layer.

Platform Adaptation Layer

Per-target platform implementations isolate chipset, OS, and driver differences from the common HAL. Representative targets are platform/broadcom/platform.c, platform/intel/platform.c, and platform/qualcomm/platform_xer5.c; other targets include Banana Pi, Raspberry Pi, an emulator, and XLE. Banana Pi additionally carries OpenWrt kernel patches under platform/banana-pi/kernel-patches_6.6/openwrt/, indicating a kernel/driver dependency for some wireless features.

Linux Wi-Fi Driver and Event Integration

The common HAL communicates with Linux wireless infrastructure through nl80211 and processes asynchronous driver events. src/wifi_hal_nl80211.c handles nl80211 interaction, src/wifi_hal_nl80211_events.c maps received events into HAL behavior, and src/wifi_hal_nl80211_utils.c supplies shared protocol/driver utilities. This is the principal boundary to kernel Wi-Fi drivers and netlink.

Access-Point and Management-Frame Processing

Hostapd integration and management/data receive paths process 802.11 traffic and route it into feature-specific logic. src/wifi_hal_hostapd.c bridges AP daemon behavior, src/wifi_hal_mgmt_rx.c handles management-frame reception, and src/wifi_hal_data_rx.c handles data frames. src/ieee80211.h provides IEEE 802.11 protocol definitions used across these paths.

Wi-Fi Feature State Machines

Specialized modules implement higher-level Wi-Fi protocols on top of received frames, hostapd, and driver state. DPP/EasyConnect is implemented by src/wifi_hal_dpp.c with a separately buildable feature component in feature_dpp/dpp.c. Passpoint-related ANQP processing is in src/wifi_hal_anqp.c; WNM/RRM functionality is in src/wifi_hal_wnm_rrm.c. These modules form protocol-specific control and packet-processing stages rather than platform implementations.

IPC Server Boundary

A HAL IPC server exposes Wi-Fi HAL operations to external local consumers, separating request handling from direct hardware access. hal_ipc/server/server_hal_ipc.c implements server orchestration, hal_ipc/server/hal_ipc_processors.c dispatches/processes requests, and hal_ipc/server/hal_ipc_wifi_wrappers.c adapts IPC operations to Wi-Fi HAL calls. Control flow is client request → IPC processor/wrapper → common HAL → platform/driver layer.

Shared Data and Cryptography

Collection utilities support common in-memory data organization in src/collection.c and util/collection.c. TLV encoding/decoding is centralized in src/wifi_tlv.c, likely supporting protocol or IPC payloads. util_crypto/aes_siv.c provides AES-SIV cryptography, a dependency relevant to secure Wi-Fi protocol processing such as DPP.