From e6c866b018ee90f694d72b181237b0038fc414ff Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Wiesner=20Andr=C3=A1s?= <wabe@mit.bme.hu>
Date: Thu, 8 Dec 2022 17:03:12 +0100
Subject: [PATCH] ARP basics added

---
 eth_interface.h                    |  1 +
 prefab/packet_parsers/arp_packet.c | 20 +++++++++++++++++
 prefab/packet_parsers/arp_packet.h | 36 ++++++++++++++++++++++++++++++
 3 files changed, 57 insertions(+)
 create mode 100644 prefab/packet_parsers/arp_packet.c
 create mode 100644 prefab/packet_parsers/arp_packet.h

diff --git a/eth_interface.h b/eth_interface.h
index a5f1f44..fcbe18f 100644
--- a/eth_interface.h
+++ b/eth_interface.h
@@ -11,6 +11,7 @@ typedef struct EthIODef_ {
     int (*llRxDone)(struct EthIODef_ * io, const RawPckt * rawPckt); ///< Receive done callback
     int (*llError)(struct EthIODef_ * io, int error); ///< Low-level error interrupt
     void * tag; ///< Some arbitrary tagging
+
 } EthIODef;
 
 typedef struct EthInterface_ {
diff --git a/prefab/packet_parsers/arp_packet.c b/prefab/packet_parsers/arp_packet.c
new file mode 100644
index 0000000..895a943
--- /dev/null
+++ b/prefab/packet_parsers/arp_packet.c
@@ -0,0 +1,20 @@
+//
+// Created by epagris on 2022.12.08..
+//
+
+#include "arp_packet.h"
+
+int parse_arp_packet(const uint8_t *hdr, uint32_t size, PcktProps * props) {
+    EthernetProps * frameProps = (EthernetProps *)props;
+    FETCH_ADVANCE(frameProps->destAddr, hdr, ETH_HW_ADDR_LEN); // copy destination address
+    FETCH_ADVANCE(frameProps->sourceAddr, hdr, ETH_HW_ADDR_LEN); // copy destination address
+    FETCH_WORD_H2N_ADVANCE(&frameProps->length_type, hdr); // copy length/type field
+
+    // fill-in packet property header fields
+    frameProps->validityOK = true;
+    frameProps->containedPacketClass =
+            frameProps->length_type <= ETH_ETHERTYPE_LENGTH_THRESHOLD ? 0 : frameProps->length_type;
+    frameProps->headerSize = ETH_ETHERNET_HEADER_SIZE;
+
+    return frameProps->containedPacketClass;
+}
\ No newline at end of file
diff --git a/prefab/packet_parsers/arp_packet.h b/prefab/packet_parsers/arp_packet.h
new file mode 100644
index 0000000..417dc55
--- /dev/null
+++ b/prefab/packet_parsers/arp_packet.h
@@ -0,0 +1,36 @@
+//
+// Created by epagris on 2022.12.08..
+//
+
+#ifndef ETHERLIB_TEST_ARP_PACKET_H
+#define ETHERLIB_TEST_ARP_PACKET_H
+
+#include <stdint.h>
+
+#define ETH_ARP_PACKET_CLASS (0x0806)
+
+/**
+ * Arp operations
+ */
+typedef enum {
+    ARPOP_REQ = 1, ///< ARP Request
+    ARPOP_REP = 2 ///< ARP Reply
+} ArpOp;
+
+typedef enum {
+    ARP_HWTYPE_ETHERNET = 1
+} ArpHwType;
+
+/**
+ * ARP properties.
+ */
+typedef struct {
+    uint16_t HTYPE; ///< Hardware type (Ethernet: 1)
+    uint16_t PTYPE; ///< Protocol type (IP: 0x0800)
+    uint8_t HLEN; ///< Hardware address length
+    uint8_t PLEN; ///< Protocol address length
+    uint16_t OPER; ///< Operation
+    uint16_t addr[]; ///< Array of addresses (SHA, SPA, THA, TPA)
+} ArpProps;
+
+#endif //ETHERLIB_TEST_ARP_PACKET_H