Move link-layer header assembly/decoding to seperate files.

1 files changed, 90 insertions, 0 deletions

diff --git a/common/ethernet.c b/common/ethernet.c
new file mode 100644
index 00000000..cfb73150
--- /dev/null
+++ b/common/ethernet.c
@@ -0,0 +1,90 @@
+/* packet.c
+
+   Packet assembly code, originally contributed by Archie Cobbs. */
+
+/*
+ * Copyright (c) 1996-1999 Internet Software Consortium.
+ * Use is subject to license terms which appear in the file named
+ * ISC-LICENSE that should have accompanied this file when you
+ * received it.   If a file named ISC-LICENSE did not accompany this
+ * file, or you are not sure the one you have is correct, you may
+ * obtain an applicable copy of the license at:
+ *
+ *             http://www.isc.org/isc-license-1.0.html. 
+ *
+ * This file is part of the ISC DHCP distribution.   The documentation
+ * associated with this file is listed in the file DOCUMENTATION,
+ * included in the top-level directory of this release.
+ *
+ * Support and other services are available for ISC products - see
+ * http://www.isc.org for more information.
+ */
+
+#ifndef lint
+static char copyright[] =
+"$Id: ethernet.c,v 1.1 1999/05/27 17:34:54 mellon Exp $ Copyright (c) 1996 The Internet Software Consortium.  All rights reserved.\n";
+#endif /* not lint */
+
+#include "dhcpd.h"
+
+#if defined (PACKET_ASSEMBLY) || defined (PACKET_DECODING)
+#include "includes/netinet/if_ether.h"
+#endif /* PACKET_ASSEMBLY || PACKET_DECODING */
+
+#if defined (PACKET_ASSEMBLY)
+/* Assemble an hardware header... */
+/* XXX currently only supports ethernet; doesn't check for other types. */
+
+void assemble_ethernet_header (interface, buf, bufix, to)
+	struct interface_info *interface;
+	unsigned char *buf;
+	int *bufix;
+	struct hardware *to;
+{
+	struct ether_header eh;
+
+	if (to && to -> hlen == 6) /* XXX */
+		memcpy (eh.ether_dhost, to -> haddr, sizeof eh.ether_dhost);
+	else
+		memset (eh.ether_dhost, 0xff, sizeof (eh.ether_dhost));
+	if (interface -> hw_address.hlen == sizeof (eh.ether_shost))
+		memcpy (eh.ether_shost, interface -> hw_address.haddr,
+			sizeof (eh.ether_shost));
+	else
+		memset (eh.ether_shost, 0x00, sizeof (eh.ether_shost));
+
+#ifdef BROKEN_FREEBSD_BPF /* Fixed in FreeBSD 2.2 */
+	eh.ether_type = ETHERTYPE_IP;
+#else
+	eh.ether_type = htons (ETHERTYPE_IP);
+#endif
+
+	memcpy (&buf [*bufix], &eh, sizeof eh);
+	*bufix += sizeof eh;
+}
+#endif /* PACKET_ASSEMBLY */
+
+#ifdef PACKET_DECODING
+/* Decode a hardware header... */
+
+ssize_t decode_ethernet_header (interface, buf, bufix, from)
+     struct interface_info *interface;
+     unsigned char *buf;
+     int bufix;
+     struct hardware *from;
+{
+  struct ether_header eh;
+
+  memcpy (&eh, buf + bufix, sizeof eh);
+
+#ifdef USERLAND_FILTER
+  if (ntohs (eh.ether_type) != ETHERTYPE_IP)
+	  return -1;
+#endif
+  memcpy (from -> haddr, eh.ether_shost, sizeof (eh.ether_shost));
+  from -> htype = ARPHRD_ETHER;
+  from -> hlen = sizeof eh.ether_shost;
+
+  return sizeof eh;
+}
+#endif /* PACKET_DECODING */