Alexander Aring wrote:
> This patch introduce different 6lowpan handling for receive and transmit
> NS/NA messages for the ipv6 neighbour discovery. The first use-case is
> for supporting 802.15.4 short addresses inside the option fields and
> handling for RFC6775 6CO option field as userspace option.
>
> Cc: David S. Miller <da...@davemloft.net>
> Cc: Alexey Kuznetsov <kuz...@ms2.inr.ac.ru>
> Cc: James Morris <jmor...@namei.org>
> Cc: Hideaki YOSHIFUJI <yoshf...@linux-ipv6.org>
> Cc: Patrick McHardy <ka...@trash.net>
> Reviewed-by: Stefan Schmidt <ste...@osg.samsung.com>
> Signed-off-by: Alexander Aring <a...@pengutronix.de>
Acked-by: YOSHIFUJI Hideaki <yoshf...@linux-ipv6.org>
> ---
> include/net/ndisc.h | 18 ++--
> net/6lowpan/6lowpan_i.h | 4 +
> net/6lowpan/Makefile | 2 +-
> net/6lowpan/core.c | 4 +-
> net/6lowpan/ndisc.c | 234
> ++++++++++++++++++++++++++++++++++++++++++++++++
> 5 files changed, 254 insertions(+), 8 deletions(-)
> create mode 100644 net/6lowpan/ndisc.c
>
> diff --git a/include/net/ndisc.h b/include/net/ndisc.h
> index 3f0f41d..be1fe228 100644
> --- a/include/net/ndisc.h
> +++ b/include/net/ndisc.h
> @@ -35,6 +35,7 @@ enum {
> ND_OPT_ROUTE_INFO = 24, /* RFC4191 */
> ND_OPT_RDNSS = 25, /* RFC5006 */
> ND_OPT_DNSSL = 31, /* RFC6106 */
> + ND_OPT_6CO = 34, /* RFC6775 */
> __ND_OPT_MAX
> };
>
> @@ -109,14 +110,19 @@ struct ndisc_options {
> #endif
> struct nd_opt_hdr *nd_useropts;
> struct nd_opt_hdr *nd_useropts_end;
> +#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
> + struct nd_opt_hdr *nd_802154_opt_array[ND_OPT_TARGET_LL_ADDR + 1];
> +#endif
> };
>
> -#define nd_opts_src_lladdr nd_opt_array[ND_OPT_SOURCE_LL_ADDR]
> -#define nd_opts_tgt_lladdr nd_opt_array[ND_OPT_TARGET_LL_ADDR]
> -#define nd_opts_pi nd_opt_array[ND_OPT_PREFIX_INFO]
> -#define nd_opts_pi_end nd_opt_array[__ND_OPT_PREFIX_INFO_END]
> -#define nd_opts_rh nd_opt_array[ND_OPT_REDIRECT_HDR]
> -#define nd_opts_mtu nd_opt_array[ND_OPT_MTU]
> +#define nd_opts_src_lladdr nd_opt_array[ND_OPT_SOURCE_LL_ADDR]
> +#define nd_opts_tgt_lladdr nd_opt_array[ND_OPT_TARGET_LL_ADDR]
> +#define nd_opts_pi nd_opt_array[ND_OPT_PREFIX_INFO]
> +#define nd_opts_pi_end
> nd_opt_array[__ND_OPT_PREFIX_INFO_END]
> +#define nd_opts_rh nd_opt_array[ND_OPT_REDIRECT_HDR]
> +#define nd_opts_mtu nd_opt_array[ND_OPT_MTU]
> +#define nd_802154_opts_src_lladdr
> nd_802154_opt_array[ND_OPT_SOURCE_LL_ADDR]
> +#define nd_802154_opts_tgt_lladdr
> nd_802154_opt_array[ND_OPT_TARGET_LL_ADDR]
>
> #define NDISC_OPT_SPACE(len) (((len)+2+7)&~7)
>
> diff --git a/net/6lowpan/6lowpan_i.h b/net/6lowpan/6lowpan_i.h
> index 97ecc27..a67caee 100644
> --- a/net/6lowpan/6lowpan_i.h
> +++ b/net/6lowpan/6lowpan_i.h
> @@ -12,6 +12,10 @@ static inline bool lowpan_is_ll(const struct net_device
> *dev,
> return lowpan_dev(dev)->lltype == lltype;
> }
>
> +extern const struct ndisc_ops lowpan_ndisc_ops;
> +
> +int addrconf_ifid_802154_6lowpan(u8 *eui, struct net_device *dev);
> +
> #ifdef CONFIG_6LOWPAN_DEBUGFS
> int lowpan_dev_debugfs_init(struct net_device *dev);
> void lowpan_dev_debugfs_exit(struct net_device *dev);
> diff --git a/net/6lowpan/Makefile b/net/6lowpan/Makefile
> index e44f3bf..12d131a 100644
> --- a/net/6lowpan/Makefile
> +++ b/net/6lowpan/Makefile
> @@ -1,6 +1,6 @@
> obj-$(CONFIG_6LOWPAN) += 6lowpan.o
>
> -6lowpan-y := core.o iphc.o nhc.o
> +6lowpan-y := core.o iphc.o nhc.o ndisc.o
> 6lowpan-$(CONFIG_6LOWPAN_DEBUGFS) += debugfs.o
>
> #rfc6282 nhcs
> diff --git a/net/6lowpan/core.c b/net/6lowpan/core.c
> index 1c7a42b..5945f7e 100644
> --- a/net/6lowpan/core.c
> +++ b/net/6lowpan/core.c
> @@ -34,6 +34,8 @@ int lowpan_register_netdevice(struct net_device *dev,
> for (i = 0; i < LOWPAN_IPHC_CTX_TABLE_SIZE; i++)
> lowpan_dev(dev)->ctx.table[i].id = i;
>
> + dev->ndisc_ops = &lowpan_ndisc_ops;
> +
> ret = register_netdevice(dev);
> if (ret < 0)
> return ret;
> @@ -73,7 +75,7 @@ void lowpan_unregister_netdev(struct net_device *dev)
> }
> EXPORT_SYMBOL(lowpan_unregister_netdev);
>
> -static int addrconf_ifid_802154_6lowpan(u8 *eui, struct net_device *dev)
> +int addrconf_ifid_802154_6lowpan(u8 *eui, struct net_device *dev)
> {
> struct wpan_dev *wpan_dev =
> lowpan_802154_dev(dev)->wdev->ieee802154_ptr;
>
> diff --git a/net/6lowpan/ndisc.c b/net/6lowpan/ndisc.c
> new file mode 100644
> index 0000000..ae1d419
> --- /dev/null
> +++ b/net/6lowpan/ndisc.c
> @@ -0,0 +1,234 @@
> +/* 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 <a...@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)
> +{
> + 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);
> + else
> + 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;
> + }
> + 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
> +};
>
--
Hideaki Yoshifuji <hideaki.yoshif...@miraclelinux.com>
Technical Division, MIRACLE LINUX CORPORATION
