Split net stack into eth/arp/ipv4/icmp, deferred handler responses, ping tests

firmware/include/arp.h

@@ -0,0 +1,28 @@
+#pragma once
+#include <functional>
+#include <span>
+#include "eth.h"
+#include "ipv4.h"
+#include "span_writer.h"
+
+namespace arp {
+
+struct __attribute__((packed)) packet {
+    eth::header eth;
+    uint16_t htype;
+    uint16_t ptype;
+    uint8_t hlen;
+    uint8_t plen;
+    uint16_t oper;
+    eth::mac_addr sha;
+    ipv4::ip4_addr spa;
+    eth::mac_addr tha;
+    ipv4::ip4_addr tpa;
+};
+static_assert(sizeof(packet) == 42);
+
+void handle(std::span<const uint8_t> frame, span_writer& tx,
+            eth::mac_addr our_mac, ipv4::ip4_addr our_ip,
+            std::function<void(std::span<const uint8_t>)> send_raw);
+
+} // namespace arp