[linux.git] / net / 6lowpan / ndisc.c

/* 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.
 *
 * Authors:
 * (C) 2016 Pengutronix, Alexander Aring <[email protected]>
 */

#include <net/6lowpan.h>
#include <net/addrconf.h>
#include <net/ndisc.h>

#include "6lowpan_i.h"

static int lowpan_ndisc_is_useropt(u8 nd_opt_type)
{
	return nd_opt_type == ND_OPT_6CO;
}

#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
#define NDISC_802154_SHORT_ADDR_LENGTH	1
static int lowpan_ndisc_parse_802154_options(const struct net_device *dev,
					     struct nd_opt_hdr *nd_opt,
					     struct ndisc_options *ndopts)
{
	switch (nd_opt->nd_opt_len) {
	case NDISC_802154_SHORT_ADDR_LENGTH:
		if (ndopts->nd_802154_opt_array[nd_opt->nd_opt_type])
			ND_PRINTK(2, warn,
				  "%s: duplicated short addr ND6 option found: type=%d\n",
				  __func__, nd_opt->nd_opt_type);
		else
			ndopts->nd_802154_opt_array[nd_opt->nd_opt_type] = nd_opt;
		return 1;
	default:
		/* all others will be handled by ndisc IPv6 option parsing */
		return 0;
	}
}

static int lowpan_ndisc_parse_options(const struct net_device *dev,
				      struct nd_opt_hdr *nd_opt,
				      struct ndisc_options *ndopts)
{
	if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154))
		return 0;

	switch (nd_opt->nd_opt_type) {
	case ND_OPT_SOURCE_LL_ADDR:
	case ND_OPT_TARGET_LL_ADDR:
		return lowpan_ndisc_parse_802154_options(dev, nd_opt, ndopts);
	default:
		return 0;
	}
}

static void lowpan_ndisc_802154_update(struct neighbour *n, u32 flags,
				       u8 icmp6_type,
				       const struct ndisc_options *ndopts)
{
	struct lowpan_802154_neigh *neigh = lowpan_802154_neigh(neighbour_priv(n));
	u8 *lladdr_short = NULL;

	switch (icmp6_type) {
	case NDISC_ROUTER_SOLICITATION:
	case NDISC_ROUTER_ADVERTISEMENT:
	case NDISC_NEIGHBOUR_SOLICITATION:
		if (ndopts->nd_802154_opts_src_lladdr) {
			lladdr_short = __ndisc_opt_addr_data(ndopts->nd_802154_opts_src_lladdr,
							     IEEE802154_SHORT_ADDR_LEN, 0);
			if (!lladdr_short) {
				ND_PRINTK(2, warn,
					  "NA: invalid short link-layer address length\n");
				return;
			}
		}
		break;
	case NDISC_REDIRECT:
	case NDISC_NEIGHBOUR_ADVERTISEMENT:
		if (ndopts->nd_802154_opts_tgt_lladdr) {
			lladdr_short = __ndisc_opt_addr_data(ndopts->nd_802154_opts_tgt_lladdr,
							     IEEE802154_SHORT_ADDR_LEN, 0);
			if (!lladdr_short) {
				ND_PRINTK(2, warn,
					  "NA: invalid short link-layer address length\n");
				return;
			}
		}
		break;
	default:
		break;
	}

	write_lock_bh(&n->lock);
	if (lladdr_short) {
		ieee802154_be16_to_le16(&neigh->short_addr, lladdr_short);
		if (!lowpan_802154_is_valid_src_short_addr(neigh->short_addr))
			neigh->short_addr = cpu_to_le16(IEEE802154_ADDR_SHORT_UNSPEC);
	}
	write_unlock_bh(&n->lock);
}

static void lowpan_ndisc_update(const struct net_device *dev,
				struct neighbour *n, u32 flags, u8 icmp6_type,
				const struct ndisc_options *ndopts)
{
	if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154))
		return;

	/* react on overrides only. TODO check if this is really right. */
	if (flags & NEIGH_UPDATE_F_OVERRIDE)
		lowpan_ndisc_802154_update(n, flags, icmp6_type, ndopts);
}

static int lowpan_ndisc_opt_addr_space(const struct net_device *dev,
				       u8 icmp6_type, struct neighbour *neigh,
				       u8 *ha_buf, u8 **ha)
{
	struct lowpan_802154_neigh *n;
	struct wpan_dev *wpan_dev;
	int addr_space = 0;

	if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154))
		return 0;

	switch (icmp6_type) {
	case NDISC_REDIRECT:
		n = lowpan_802154_neigh(neighbour_priv(neigh));

		read_lock_bh(&neigh->lock);
		if (lowpan_802154_is_valid_src_short_addr(n->short_addr)) {
			memcpy(ha_buf, &n->short_addr,
			       IEEE802154_SHORT_ADDR_LEN);
			read_unlock_bh(&neigh->lock);
			addr_space += __ndisc_opt_addr_space(IEEE802154_SHORT_ADDR_LEN, 0);
			*ha = ha_buf;
		} else {
			read_unlock_bh(&neigh->lock);
		}
		break;
	case NDISC_NEIGHBOUR_ADVERTISEMENT:
	case NDISC_NEIGHBOUR_SOLICITATION:
	case NDISC_ROUTER_SOLICITATION:
		wpan_dev = lowpan_802154_dev(dev)->wdev->ieee802154_ptr;

		if (lowpan_802154_is_valid_src_short_addr(wpan_dev->short_addr))
			addr_space = __ndisc_opt_addr_space(IEEE802154_SHORT_ADDR_LEN, 0);
		break;
	default:
		break;
	}

	return addr_space;
}

static void lowpan_ndisc_fill_addr_option(const struct net_device *dev,
					  struct sk_buff *skb, u8 icmp6_type,
					  const u8 *ha)
{
	struct wpan_dev *wpan_dev;
	__be16 short_addr;
	u8 opt_type;

	if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154))
		return;

	switch (icmp6_type) {
	case NDISC_REDIRECT:
		if (ha) {
			ieee802154_le16_to_be16(&short_addr, ha);
			__ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR,
						 &short_addr,
						 IEEE802154_SHORT_ADDR_LEN, 0);
		}
		return;
	case NDISC_NEIGHBOUR_ADVERTISEMENT:
		opt_type = ND_OPT_TARGET_LL_ADDR;
		break;
	case NDISC_ROUTER_SOLICITATION:
	case NDISC_NEIGHBOUR_SOLICITATION:
		opt_type = ND_OPT_SOURCE_LL_ADDR;
		break;
	default:
		return;
	}

	wpan_dev = lowpan_802154_dev(dev)->wdev->ieee802154_ptr;

	if (lowpan_802154_is_valid_src_short_addr(wpan_dev->short_addr)) {
		ieee802154_le16_to_be16(&short_addr,
					&wpan_dev->short_addr);
		__ndisc_fill_addr_option(skb, opt_type, &short_addr,
					 IEEE802154_SHORT_ADDR_LEN, 0);
	}
}

static void lowpan_ndisc_prefix_rcv_add_addr(struct net *net,
					     struct net_device *dev,
					     const struct prefix_info *pinfo,
					     struct inet6_dev *in6_dev,
					     struct in6_addr *addr,
					     int addr_type, u32 addr_flags,
					     bool sllao, bool tokenized,
					     __u32 valid_lft,
					     u32 prefered_lft,
					     bool dev_addr_generated)
{
	int err;

	/* generates short based address for RA PIO's */
	if (lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154) && dev_addr_generated &&
	    !addrconf_ifid_802154_6lowpan(addr->s6_addr + 8, dev)) {
		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
						   addr, addr_type, addr_flags,
						   sllao, tokenized, valid_lft,
						   prefered_lft);
		if (err)
			ND_PRINTK(2, warn,
				  "RA: could not add a short address based address for prefix: %pI6c\n",
				  &pinfo->prefix);
	}
}
#endif

const struct ndisc_ops lowpan_ndisc_ops = {
	.is_useropt		= lowpan_ndisc_is_useropt,
#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
	.parse_options		= lowpan_ndisc_parse_options,
	.update			= lowpan_ndisc_update,
	.opt_addr_space		= lowpan_ndisc_opt_addr_space,
	.fill_addr_option	= lowpan_ndisc_fill_addr_option,
	.prefix_rcv_add_addr	= lowpan_ndisc_prefix_rcv_add_addr,
#endif
};
Commit	Line	Data
bbe5f5ce AA	1	/* This program is free software; you can redistribute it and/or modify
	2	* it under the terms of the GNU General Public License version 2
	3	* as published by the Free Software Foundation.
	4	*
	5	* This program is distributed in the hope that it will be useful,
	6	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	7	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	8	* GNU General Public License for more details.
	9	*
	10	* Authors:
	11	* (C) 2016 Pengutronix, Alexander Aring <[email protected]>
	12	*/
	13
	14	#include <net/6lowpan.h>
	15	#include <net/addrconf.h>
	16	#include <net/ndisc.h>
	17
	18	#include "6lowpan_i.h"
	19
	20	static int lowpan_ndisc_is_useropt(u8 nd_opt_type)
	21	{
	22	return nd_opt_type == ND_OPT_6CO;
	23	}
	24
	25	#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
	26	#define NDISC_802154_SHORT_ADDR_LENGTH 1
	27	static int lowpan_ndisc_parse_802154_options(const struct net_device *dev,
	28	struct nd_opt_hdr *nd_opt,
	29	struct ndisc_options *ndopts)
	30	{
	31	switch (nd_opt->nd_opt_len) {
	32	case NDISC_802154_SHORT_ADDR_LENGTH:
	33	if (ndopts->nd_802154_opt_array[nd_opt->nd_opt_type])
	34	ND_PRINTK(2, warn,
	35	"%s: duplicated short addr ND6 option found: type=%d\n",
	36	__func__, nd_opt->nd_opt_type);
	37	else
	38	ndopts->nd_802154_opt_array[nd_opt->nd_opt_type] = nd_opt;
	39	return 1;
	40	default:
	41	/* all others will be handled by ndisc IPv6 option parsing */
	42	return 0;
	43	}
	44	}
	45
	46	static int lowpan_ndisc_parse_options(const struct net_device *dev,
	47	struct nd_opt_hdr *nd_opt,
	48	struct ndisc_options *ndopts)
	49	{
966be9e7 AA	50	if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154))
	51	return 0;
	52
bbe5f5ce AA	53	switch (nd_opt->nd_opt_type) {
	54	case ND_OPT_SOURCE_LL_ADDR:
	55	case ND_OPT_TARGET_LL_ADDR:
	56	return lowpan_ndisc_parse_802154_options(dev, nd_opt, ndopts);
	57	default:
	58	return 0;
	59	}
	60	}
	61
	62	static void lowpan_ndisc_802154_update(struct neighbour *n, u32 flags,
	63	u8 icmp6_type,
	64	const struct ndisc_options *ndopts)
	65	{
	66	struct lowpan_802154_neigh *neigh = lowpan_802154_neigh(neighbour_priv(n));
	67	u8 *lladdr_short = NULL;
	68
	69	switch (icmp6_type) {
	70	case NDISC_ROUTER_SOLICITATION:
	71	case NDISC_ROUTER_ADVERTISEMENT:
	72	case NDISC_NEIGHBOUR_SOLICITATION:
	73	if (ndopts->nd_802154_opts_src_lladdr) {
	74	lladdr_short = __ndisc_opt_addr_data(ndopts->nd_802154_opts_src_lladdr,
	75	IEEE802154_SHORT_ADDR_LEN, 0);
	76	if (!lladdr_short) {
	77	ND_PRINTK(2, warn,
	78	"NA: invalid short link-layer address length\n");
	79	return;
	80	}
	81	}
	82	break;
	83	case NDISC_REDIRECT:
	84	case NDISC_NEIGHBOUR_ADVERTISEMENT:
	85	if (ndopts->nd_802154_opts_tgt_lladdr) {
	86	lladdr_short = __ndisc_opt_addr_data(ndopts->nd_802154_opts_tgt_lladdr,
	87	IEEE802154_SHORT_ADDR_LEN, 0);
	88	if (!lladdr_short) {
	89	ND_PRINTK(2, warn,
	90	"NA: invalid short link-layer address length\n");
	91	return;
	92	}
	93	}
	94	break;
	95	default:
	96	break;
	97	}
	98
	99	write_lock_bh(&n->lock);
9e262f50	100	if (lladdr_short) {
bbe5f5ce	101	ieee802154_be16_to_le16(&neigh->short_addr, lladdr_short);
9e262f50 AA	102	if (!lowpan_802154_is_valid_src_short_addr(neigh->short_addr))
9e262f50 AA	103	neigh->short_addr = cpu_to_le16(IEEE802154_ADDR_SHORT_UNSPEC);
9e262f50	104	}
bbe5f5ce AA	105	write_unlock_bh(&n->lock);
	106	}
	107
	108	static void lowpan_ndisc_update(const struct net_device *dev,
	109	struct neighbour *n, u32 flags, u8 icmp6_type,
	110	const struct ndisc_options *ndopts)
	111	{
	112	if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154))
	113	return;
	114
	115	/* react on overrides only. TODO check if this is really right. */
	116	if (flags & NEIGH_UPDATE_F_OVERRIDE)
	117	lowpan_ndisc_802154_update(n, flags, icmp6_type, ndopts);
	118	}
	119
	120	static int lowpan_ndisc_opt_addr_space(const struct net_device *dev,
	121	u8 icmp6_type, struct neighbour *neigh,
	122	u8 ha_buf, u8 *ha)
	123	{
	124	struct lowpan_802154_neigh *n;
	125	struct wpan_dev *wpan_dev;
	126	int addr_space = 0;
	127
	128	if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154))
	129	return 0;
	130
	131	switch (icmp6_type) {
	132	case NDISC_REDIRECT:
	133	n = lowpan_802154_neigh(neighbour_priv(neigh));
	134
	135	read_lock_bh(&neigh->lock);
	136	if (lowpan_802154_is_valid_src_short_addr(n->short_addr)) {
	137	memcpy(ha_buf, &n->short_addr,
	138	IEEE802154_SHORT_ADDR_LEN);
	139	read_unlock_bh(&neigh->lock);
	140	addr_space += __ndisc_opt_addr_space(IEEE802154_SHORT_ADDR_LEN, 0);
	141	*ha = ha_buf;
929946a4 AA	142	} else {
929946a4 AA	143	read_unlock_bh(&neigh->lock);
bbe5f5ce	144	}
bbe5f5ce AA	145	break;
	146	case NDISC_NEIGHBOUR_ADVERTISEMENT:
	147	case NDISC_NEIGHBOUR_SOLICITATION:
	148	case NDISC_ROUTER_SOLICITATION:
	149	wpan_dev = lowpan_802154_dev(dev)->wdev->ieee802154_ptr;
	150
	151	if (lowpan_802154_is_valid_src_short_addr(wpan_dev->short_addr))
	152	addr_space = __ndisc_opt_addr_space(IEEE802154_SHORT_ADDR_LEN, 0);
	153	break;
	154	default:
	155	break;
	156	}
	157
	158	return addr_space;
	159	}
	160
	161	static void lowpan_ndisc_fill_addr_option(const struct net_device *dev,
	162	struct sk_buff *skb, u8 icmp6_type,
	163	const u8 *ha)
	164	{
	165	struct wpan_dev *wpan_dev;
	166	__be16 short_addr;
	167	u8 opt_type;
	168
	169	if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154))
	170	return;
	171
	172	switch (icmp6_type) {
	173	case NDISC_REDIRECT:
	174	if (ha) {
	175	ieee802154_le16_to_be16(&short_addr, ha);
	176	__ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR,
	177	&short_addr,
	178	IEEE802154_SHORT_ADDR_LEN, 0);
	179	}
	180	return;
	181	case NDISC_NEIGHBOUR_ADVERTISEMENT:
	182	opt_type = ND_OPT_TARGET_LL_ADDR;
	183	break;
	184	case NDISC_ROUTER_SOLICITATION:
	185	case NDISC_NEIGHBOUR_SOLICITATION:
	186	opt_type = ND_OPT_SOURCE_LL_ADDR;
	187	break;
	188	default:
	189	return;
	190	}
	191
	192	wpan_dev = lowpan_802154_dev(dev)->wdev->ieee802154_ptr;
	193
	194	if (lowpan_802154_is_valid_src_short_addr(wpan_dev->short_addr)) {
	195	ieee802154_le16_to_be16(&short_addr,
	196	&wpan_dev->short_addr);
	197	__ndisc_fill_addr_option(skb, opt_type, &short_addr,
	198	IEEE802154_SHORT_ADDR_LEN, 0);
	199	}
	200	}
	201
	202	static void lowpan_ndisc_prefix_rcv_add_addr(struct net *net,
	203	struct net_device *dev,
	204	const struct prefix_info *pinfo,
	205	struct inet6_dev *in6_dev,
	206	struct in6_addr *addr,
	207	int addr_type, u32 addr_flags,
	208	bool sllao, bool tokenized,
209	__u32 valid_lft,
210	u32 prefered_lft,
211	bool dev_addr_generated)
212	{
213	int err;
214
215	/* generates short based address for RA PIO's */
216	if (lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154) && dev_addr_generated &&
217	!addrconf_ifid_802154_6lowpan(addr->s6_addr + 8, dev)) {
218	err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
219	addr, addr_type, addr_flags,
220	sllao, tokenized, valid_lft,
221	prefered_lft);
222	if (err)
223	ND_PRINTK(2, warn,
224	"RA: could not add a short address based address for prefix: %pI6c\n",
225	&pinfo->prefix);
226	}
227	}
228	#endif
229
230	const struct ndisc_ops lowpan_ndisc_ops = {
231	.is_useropt = lowpan_ndisc_is_useropt,
232	#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
233	.parse_options = lowpan_ndisc_parse_options,
234	.update = lowpan_ndisc_update,
235	.opt_addr_space = lowpan_ndisc_opt_addr_space,
236	.fill_addr_option = lowpan_ndisc_fill_addr_option,
237	.prefix_rcv_add_addr = lowpan_ndisc_prefix_rcv_add_addr,
238	#endif
239	};