/* 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 <aar@pengutronix.de>
*/
#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
};
