IEEE802.15.4: 6LoWPAN basic support

This patch provides base support for transmission of IPv6 packets as
well as the formation of IPv6 link-local addresses and statelessly
autoconfigured addresses on top of IEEE 802.15.4 networks.

For more information please look at the RFC4944 "Compression Format
for IPv6 Datagrams in Low Power and Losst Networks (6LoWPAN).
Signed-off-by: Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ieee802154/6lowpan.h

+/*
+ * Copyright 2011, Siemens AG
+ * written by Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
+ */
+
+/*
+ * Based on patches from Jon Smirl <jonsmirl@gmail.com>
+ * Copyright (c) 2011 Jon Smirl <jonsmirl@gmail.com>
+ *
+ * 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; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+/* Jon's code is based on 6lowpan implementation for Contiki which is:
+ * Copyright (c) 2008, Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the Institute nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef __6LOWPAN_H__
+#define __6LOWPAN_H__
+
+/* need to know address length to manipulate with it */
+#define IEEE802154_ALEN		8
+
+#define UIP_802154_SHORTADDR_LEN	2  /* compressed ipv6 address length */
+#define UIP_IPH_LEN			40 /* ipv6 fixed header size */
+#define UIP_PROTO_UDP			17 /* ipv6 next header value for UDP */
+#define UIP_FRAGH_LEN			8  /* ipv6 fragment header size */
+
+/*
+ * ipv6 address based on mac
+ * second bit-flip (Universe/Local) is done according RFC2464
+ */
+#define is_addr_mac_addr_based(a, m) \
+	((((a)->s6_addr[8])  == (((m)[0]) ^ 0x02)) &&	\
+	 (((a)->s6_addr[9])  == (m)[1]) &&		\
+	 (((a)->s6_addr[10]) == (m)[2]) &&		\
+	 (((a)->s6_addr[11]) == (m)[3]) &&		\
+	 (((a)->s6_addr[12]) == (m)[4]) &&		\
+	 (((a)->s6_addr[13]) == (m)[5]) &&		\
+	 (((a)->s6_addr[14]) == (m)[6]) &&		\
+	 (((a)->s6_addr[15]) == (m)[7]))
+
+/* ipv6 address is unspecified */
+#define is_addr_unspecified(a)		\
+	((((a)->s6_addr32[0]) == 0) &&	\
+	 (((a)->s6_addr32[1]) == 0) &&	\
+	 (((a)->s6_addr32[2]) == 0) &&	\
+	 (((a)->s6_addr32[3]) == 0))
+
+/* compare ipv6 addresses prefixes */
+#define ipaddr_prefixcmp(addr1, addr2, length) \
+	(memcmp(addr1, addr2, length >> 3) == 0)
+
+/* local link, i.e. FE80::/10 */
+#define is_addr_link_local(a) (((a)->s6_addr16[0]) == 0x80FE)
+
+/*
+ * check whether we can compress the IID to 16 bits,
+ * it's possible for unicast adresses with first 49 bits are zero only.
+ */
+#define lowpan_is_iid_16_bit_compressable(a)	\
+	((((a)->s6_addr16[4]) == 0) &&		\
+	 (((a)->s6_addr16[5]) == 0) &&		\
+	 (((a)->s6_addr16[6]) == 0) &&		\
+	 ((((a)->s6_addr[14]) & 0x80) == 0))
+
+/* multicast address */
+#define is_addr_mcast(a) (((a)->s6_addr[0]) == 0xFF)
+
+/* check whether the 112-bit gid of the multicast address is mappable to: */
+
+/* 9 bits, for FF02::1 (all nodes) and FF02::2 (all routers) addresses only. */
+#define lowpan_is_mcast_addr_compressable(a)	\
+	((((a)->s6_addr16[1]) == 0) &&		\
+	 (((a)->s6_addr16[2]) == 0) &&		\
+	 (((a)->s6_addr16[3]) == 0) &&		\
+	 (((a)->s6_addr16[4]) == 0) &&		\
+	 (((a)->s6_addr16[5]) == 0) &&		\
+	 (((a)->s6_addr16[6]) == 0) &&		\
+	 (((a)->s6_addr[14])  == 0) &&		\
+	 ((((a)->s6_addr[15]) == 1) || (((a)->s6_addr[15]) == 2)))
+
+/* 48 bits, FFXX::00XX:XXXX:XXXX */
+#define lowpan_is_mcast_addr_compressable48(a)	\
+	((((a)->s6_addr16[1]) == 0) &&		\
+	 (((a)->s6_addr16[2]) == 0) &&		\
+	 (((a)->s6_addr16[3]) == 0) &&		\
+	 (((a)->s6_addr16[4]) == 0) &&		\
+	 (((a)->s6_addr[10]) == 0))
+
+/* 32 bits, FFXX::00XX:XXXX */
+#define lowpan_is_mcast_addr_compressable32(a)	\
+	((((a)->s6_addr16[1]) == 0) &&		\
+	 (((a)->s6_addr16[2]) == 0) &&		\
+	 (((a)->s6_addr16[3]) == 0) &&		\
+	 (((a)->s6_addr16[4]) == 0) &&		\
+	 (((a)->s6_addr16[5]) == 0) &&		\
+	 (((a)->s6_addr[12]) == 0))
+
+/* 8 bits, FF02::00XX */
+#define lowpan_is_mcast_addr_compressable8(a)	\
+	((((a)->s6_addr[1])  == 2) &&		\
+	 (((a)->s6_addr16[1]) == 0) &&		\
+	 (((a)->s6_addr16[2]) == 0) &&		\
+	 (((a)->s6_addr16[3]) == 0) &&		\
+	 (((a)->s6_addr16[4]) == 0) &&		\
+	 (((a)->s6_addr16[5]) == 0) &&		\
+	 (((a)->s6_addr16[6]) == 0) &&		\
+	 (((a)->s6_addr[14]) == 0))
+
+#define lowpan_is_addr_broadcast(a)	\
+	((((a)[0]) == 0xFF) &&	\
+	 (((a)[1]) == 0xFF) &&	\
+	 (((a)[2]) == 0xFF) &&	\
+	 (((a)[3]) == 0xFF) &&	\
+	 (((a)[4]) == 0xFF) &&	\
+	 (((a)[5]) == 0xFF) &&	\
+	 (((a)[6]) == 0xFF) &&	\
+	 (((a)[7]) == 0xFF))
+
+#define LOWPAN_DISPATCH_IPV6	0x41 /* 01000001 = 65 */
+#define LOWPAN_DISPATCH_HC1	0x42 /* 01000010 = 66 */
+#define LOWPAN_DISPATCH_IPHC	0x60 /* 011xxxxx = ... */
+#define LOWPAN_DISPATCH_FRAG1	0xc0 /* 11000xxx */
+#define LOWPAN_DISPATCH_FRAGN	0xe0 /* 11100xxx */
+
+/*
+ * Values of fields within the IPHC encoding first byte
+ * (C stands for compressed and I for inline)
+ */
+#define LOWPAN_IPHC_TF		0x18
+
+#define LOWPAN_IPHC_FL_C	0x10
+#define LOWPAN_IPHC_TC_C	0x08
+#define LOWPAN_IPHC_NH_C	0x04
+#define LOWPAN_IPHC_TTL_1	0x01
+#define LOWPAN_IPHC_TTL_64	0x02
+#define LOWPAN_IPHC_TTL_255	0x03
+#define LOWPAN_IPHC_TTL_I	0x00
+
+
+/* Values of fields within the IPHC encoding second byte */
+#define LOWPAN_IPHC_CID		0x80
+
+#define LOWPAN_IPHC_SAC		0x40
+#define LOWPAN_IPHC_SAM_00	0x00
+#define LOWPAN_IPHC_SAM_01	0x10
+#define LOWPAN_IPHC_SAM_10	0x20
+#define LOWPAN_IPHC_SAM		0x30
+
+#define LOWPAN_IPHC_SAM_BIT	4
+
+#define LOWPAN_IPHC_M		0x08
+#define LOWPAN_IPHC_DAC		0x04
+#define LOWPAN_IPHC_DAM_00	0x00
+#define LOWPAN_IPHC_DAM_01	0x01
+#define LOWPAN_IPHC_DAM_10	0x02
+#define LOWPAN_IPHC_DAM_11	0x03
+
+#define LOWPAN_IPHC_DAM_BIT	0
+/*
+ * LOWPAN_UDP encoding (works together with IPHC)
+ */
+#define LOWPAN_NHC_UDP_MASK		0xF8
+#define LOWPAN_NHC_UDP_ID		0xF0
+#define LOWPAN_NHC_UDP_CHECKSUMC	0x04
+#define LOWPAN_NHC_UDP_CHECKSUMI	0x00
+
+/* values for port compression, _with checksum_ ie bit 5 set to 0 */
+#define LOWPAN_NHC_UDP_CS_P_00	0xF0 /* all inline */
+#define LOWPAN_NHC_UDP_CS_P_01	0xF1 /* source 16bit inline,
+					dest = 0xF0 + 8 bit inline */
+#define LOWPAN_NHC_UDP_CS_P_10	0xF2 /* source = 0xF0 + 8bit inline,
+					dest = 16 bit inline */
+#define LOWPAN_NHC_UDP_CS_P_11	0xF3 /* source & dest = 0xF0B + 4bit inline */
+
+#endif /* __6LOWPAN_H__ */

net/ieee802154/Kconfig

@@ -10,3 +10,9 @@ config IEEE802154
 
 	  Say Y here to compile LR-WPAN support into the kernel or say M to
 	  compile it as modules.
+
+config IEEE802154_6LOWPAN
+	tristate "6lowpan support over IEEE 802.15.4"
+	depends on IEEE802154 && IPV6
+	---help---
+	IPv6 compression over IEEE 802.15.4.

net/ieee802154/Makefile

 obj-$(CONFIG_IEEE802154) += ieee802154.o af_802154.o
+obj-$(CONFIG_IEEE802154_6LOWPAN) += 6lowpan.o
+
 ieee802154-y := netlink.o nl-mac.o nl-phy.o nl_policy.o wpan-class.o
 af_802154-y := af_ieee802154.o raw.o dgram.o