Tap driver basically builds in VS2012... fork of tap-windows from OpenVPN (compatible license).

vsprojects/TapDriver/dhcp.h

@@ -0,0 +1,164 @@
+/*
+ *  TAP-Windows -- A kernel driver to provide virtual tap
+ *                 device functionality on Windows.
+ *
+ *  This code was inspired by the CIPE-Win32 driver by Damion K. Wilson.
+ *
+ *  This source code is Copyright (C) 2002-2010 OpenVPN Technologies, Inc.,
+ *  and is released under the GPL version 2 (see below).
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program (see the file COPYING included with this
+ *  distribution); if not, write to the Free Software Foundation, Inc.,
+ *  59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#pragma pack(1)
+
+//===================================================
+// How many bad DHCPREQUESTs do we receive before we
+// return a NAK?
+//
+// A bad DHCPREQUEST is defined to be one where the
+// requestor doesn't know its IP address.
+//===================================================
+
+#define BAD_DHCPREQUEST_NAK_THRESHOLD 3
+
+//==============================================
+// Maximum number of DHCP options bytes supplied
+//==============================================
+
+#define DHCP_USER_SUPPLIED_OPTIONS_BUFFER_SIZE 256
+#define DHCP_OPTIONS_BUFFER_SIZE               256
+
+//===================================
+// UDP port numbers of DHCP messages.
+//===================================
+
+#define BOOTPS_PORT 67
+#define BOOTPC_PORT 68
+
+//===========================
+// The DHCP message structure
+//===========================
+
+typedef struct {
+# define BOOTREQUEST 1
+# define BOOTREPLY   2
+  UCHAR op;          /* message op */
+
+  UCHAR  htype;      /* hardware address type (e.g. '1' = 10Mb Ethernet) */
+  UCHAR  hlen;       /* hardware address length (e.g. '6' for 10Mb Ethernet) */
+  UCHAR  hops;       /* client sets to 0, may be used by relay agents */
+  ULONG  xid;        /* transaction ID, chosen by client */
+  USHORT secs;       /* seconds since request process began, set by client */
+  USHORT flags;
+  ULONG  ciaddr;     /* client IP address, client sets if known */
+  ULONG  yiaddr;     /* 'your' IP address -- server's response to client */
+  ULONG  siaddr;     /* server IP address */
+  ULONG  giaddr;     /* relay agent IP address */
+  UCHAR  chaddr[16]; /* client hardware address */
+  UCHAR  sname[64];  /* optional server host name */
+  UCHAR  file[128];  /* boot file name */
+  ULONG  magic;      /* must be 0x63825363 (network order) */
+} DHCP;
+
+typedef struct {
+  ETH_HEADER eth;
+  IPHDR ip;
+  UDPHDR udp;
+  DHCP dhcp;
+} DHCPPre;
+
+typedef struct {
+  DHCPPre pre;
+  UCHAR options[DHCP_OPTIONS_BUFFER_SIZE];
+} DHCPFull;
+
+typedef struct {
+  unsigned int optlen;
+  BOOLEAN overflow;
+  DHCPFull msg;
+} DHCPMsg;
+
+//===================
+// Macros for DHCPMSG
+//===================
+
+#define DHCPMSG_LEN_BASE(p) (sizeof (DHCPPre))
+#define DHCPMSG_LEN_OPT(p)  ((p)->optlen)
+#define DHCPMSG_LEN_FULL(p) (DHCPMSG_LEN_BASE(p) + DHCPMSG_LEN_OPT(p))
+#define DHCPMSG_BUF(p)      ((UCHAR*) &(p)->msg)
+#define DHCPMSG_OVERFLOW(p) ((p)->overflow)
+
+//========================================
+// structs to hold individual DHCP options
+//========================================
+
+typedef struct {
+  UCHAR type;
+} DHCPOPT0;
+
+typedef struct {
+  UCHAR type;
+  UCHAR len;
+  UCHAR data;
+} DHCPOPT8;
+
+typedef struct {
+  UCHAR type;
+  UCHAR len;
+  ULONG data;
+} DHCPOPT32;
+
+#pragma pack()
+
+//==================
+// DHCP Option types
+//==================
+
+#define DHCP_MSG_TYPE    53  /* message type (u8) */
+#define DHCP_PARM_REQ    55  /* parameter request list: c1 (u8), ... */
+#define DHCP_CLIENT_ID   61  /* client ID: type (u8), i1 (u8), ... */
+#define DHCP_IP          50  /* requested IP addr (u32) */
+#define DHCP_NETMASK      1  /* subnet mask (u32) */
+#define DHCP_LEASE_TIME  51  /* lease time sec (u32) */
+#define DHCP_RENEW_TIME  58  /* renewal time sec (u32) */
+#define DHCP_REBIND_TIME 59  /* rebind time sec (u32) */
+#define DHCP_SERVER_ID   54  /* server ID: IP addr (u32) */
+#define DHCP_PAD          0
+#define DHCP_END        255
+
+//====================
+// DHCP Messages types
+//====================
+
+#define DHCPDISCOVER 1
+#define DHCPOFFER    2
+#define DHCPREQUEST  3
+#define DHCPDECLINE  4
+#define DHCPACK      5
+#define DHCPNAK      6
+#define DHCPRELEASE  7
+#define DHCPINFORM   8
+
+#if DBG
+
+VOID
+DumpDHCP (const ETH_HEADER *eth,
+	  const IPHDR *ip,
+	  const UDPHDR *udp,
+	  const DHCP *dhcp,
+	  const int optlen);
+
+#endif