From 4e0ed09d71023ce823ce3f66800a6aa68e3527ea Mon Sep 17 00:00:00 2001
From: Paul Hollinsky <phollinsky@intrepidcs.com>
Date: Mon, 6 May 2019 13:48:42 -0400
Subject: [PATCH] POSIX PCAP: Platform agnostic MAC address discovery

---
 include/icsneo/platform/posix/darwin/macaddr.h | 11 +++++++++++
 include/icsneo/platform/posix/linux/macaddr.h  | 11 +++++++++++
 include/icsneo/platform/posix/macaddr.h        | 10 ++++++++++
 platform/posix/pcap.cpp                        |  7 +++----
 4 files changed, 35 insertions(+), 4 deletions(-)
 create mode 100644 include/icsneo/platform/posix/darwin/macaddr.h
 create mode 100644 include/icsneo/platform/posix/linux/macaddr.h
 create mode 100644 include/icsneo/platform/posix/macaddr.h

diff --git a/include/icsneo/platform/posix/darwin/macaddr.h b/include/icsneo/platform/posix/darwin/macaddr.h
new file mode 100644
index 0000000..8e988a1
--- /dev/null
+++ b/include/icsneo/platform/posix/darwin/macaddr.h
@@ -0,0 +1,11 @@
+#ifndef __MACADDR_DARWIN_H_
+#define __MACADDR_DARWIN_H_
+
+#include <net/if_dl.h>
+
+#define ICSNEO_AF_MACADDR (AF_LINK)
+
+// Points towards the first byte of the MAC address, given a sockaddr*
+#define PLATFORM_MAC_FROM_SOCKADDR(SADDR) (((struct sockaddr_dl*)SADDR)->sdl_data + ((struct sockaddr_dl*)SADDR)->sdl_nlen)
+
+#endif
\ No newline at end of file
diff --git a/include/icsneo/platform/posix/linux/macaddr.h b/include/icsneo/platform/posix/linux/macaddr.h
new file mode 100644
index 0000000..3af0c7c
--- /dev/null
+++ b/include/icsneo/platform/posix/linux/macaddr.h
@@ -0,0 +1,11 @@
+#ifndef __MACADDR_LINUX_H_
+#define __MACADDR_LINUX_H_
+
+#include <netpacket/packet.h>
+
+#define ICSNEO_AF_MACADDR (AF_PACKET)
+
+// Points towards the first byte of the MAC address, given a sockaddr*
+#define PLATFORM_MAC_FROM_SOCKADDR(SADDR) (((struct sockaddr_ll*)SADDR)->sll_addr)
+
+#endif
\ No newline at end of file
diff --git a/include/icsneo/platform/posix/macaddr.h b/include/icsneo/platform/posix/macaddr.h
new file mode 100644
index 0000000..74b1e2f
--- /dev/null
+++ b/include/icsneo/platform/posix/macaddr.h
@@ -0,0 +1,10 @@
+#ifndef __MACADDR_POSIX_H_
+#define __MACADDR_POSIX_H_
+
+#ifdef __APPLE__
+#include "icsneo/platform/posix/darwin/macaddr.h"
+#else
+#include "icsneo/platform/posix/linux/macaddr.h"
+#endif
+
+#endif
\ No newline at end of file
diff --git a/platform/posix/pcap.cpp b/platform/posix/pcap.cpp
index 22589d3..5933161 100644
--- a/platform/posix/pcap.cpp
+++ b/platform/posix/pcap.cpp
@@ -2,13 +2,13 @@
 #include "icsneo/communication/network.h"
 #include "icsneo/communication/communication.h"
 #include "icsneo/communication/packetizer.h"
+#include "icsneo/platform/posix/macaddr.h"
 #include <codecvt>
 #include <chrono>
 #include <iostream>
 #include <cstring>
 #include <sys/types.h>
 #include <sys/socket.h>
-#include <netpacket/packet.h>
 
 using namespace icsneo;
 
@@ -52,9 +52,8 @@ std::vector<PCAP::PCAPFoundDevice> PCAP::FindAll() {
 		pcap_addr* currentAddress = dev->addresses;
 		bool hasAddress = false;
 		while(!hasAddress && currentAddress != nullptr) {
-			if(currentAddress->addr && currentAddress->addr->sa_family == AF_PACKET) {
-				struct sockaddr_ll* s = (struct sockaddr_ll*)currentAddress->addr;
-				memcpy(netif.macAddress, s->sll_addr, sizeof(netif.macAddress));
+			if(currentAddress->addr && currentAddress->addr->sa_family == ICSNEO_AF_MACADDR) {
+				memcpy(netif.macAddress, PLATFORM_MAC_FROM_SOCKADDR(currentAddress->addr), sizeof(netif.macAddress));
 				hasAddress = true;
 				break;
 			}