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 <aar@pengutronix.de> 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 { 50 if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154)) 51 return 0; 52 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); 100 if (lladdr_short) { 101 ieee802154_be16_to_le16(&neigh->short_addr, lladdr_short); 102 if (!lowpan_802154_is_valid_src_short_addr(neigh->short_addr)) 103 neigh->short_addr = cpu_to_le16(IEEE802154_ADDR_SHORT_UNSPEC); 104 } else { 105 neigh->short_addr = cpu_to_le16(IEEE802154_ADDR_SHORT_UNSPEC); 106 } 107 write_unlock_bh(&n->lock); 108 } 109 110 static void lowpan_ndisc_update(const struct net_device *dev, 111 struct neighbour *n, u32 flags, u8 icmp6_type, 112 const struct ndisc_options *ndopts) 113 { 114 if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154)) 115 return; 116 117 /* react on overrides only. TODO check if this is really right. */ 118 if (flags & NEIGH_UPDATE_F_OVERRIDE) 119 lowpan_ndisc_802154_update(n, flags, icmp6_type, ndopts); 120 } 121 122 static int lowpan_ndisc_opt_addr_space(const struct net_device *dev, 123 u8 icmp6_type, struct neighbour *neigh, 124 u8 *ha_buf, u8 **ha) 125 { 126 struct lowpan_802154_neigh *n; 127 struct wpan_dev *wpan_dev; 128 int addr_space = 0; 129 130 if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154)) 131 return 0; 132 133 switch (icmp6_type) { 134 case NDISC_REDIRECT: 135 n = lowpan_802154_neigh(neighbour_priv(neigh)); 136 137 read_lock_bh(&neigh->lock); 138 if (lowpan_802154_is_valid_src_short_addr(n->short_addr)) { 139 memcpy(ha_buf, &n->short_addr, 140 IEEE802154_SHORT_ADDR_LEN); 141 read_unlock_bh(&neigh->lock); 142 addr_space += __ndisc_opt_addr_space(IEEE802154_SHORT_ADDR_LEN, 0); 143 *ha = ha_buf; 144 } else { 145 read_unlock_bh(&neigh->lock); 146 } 147 break; 148 case NDISC_NEIGHBOUR_ADVERTISEMENT: 149 case NDISC_NEIGHBOUR_SOLICITATION: 150 case NDISC_ROUTER_SOLICITATION: 151 wpan_dev = lowpan_802154_dev(dev)->wdev->ieee802154_ptr; 152 153 if (lowpan_802154_is_valid_src_short_addr(wpan_dev->short_addr)) 154 addr_space = __ndisc_opt_addr_space(IEEE802154_SHORT_ADDR_LEN, 0); 155 break; 156 default: 157 break; 158 } 159 160 return addr_space; 161 } 162 163 static void lowpan_ndisc_fill_addr_option(const struct net_device *dev, 164 struct sk_buff *skb, u8 icmp6_type, 165 const u8 *ha) 166 { 167 struct wpan_dev *wpan_dev; 168 __be16 short_addr; 169 u8 opt_type; 170 171 if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154)) 172 return; 173 174 switch (icmp6_type) { 175 case NDISC_REDIRECT: 176 if (ha) { 177 ieee802154_le16_to_be16(&short_addr, ha); 178 __ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR, 179 &short_addr, 180 IEEE802154_SHORT_ADDR_LEN, 0); 181 } 182 return; 183 case NDISC_NEIGHBOUR_ADVERTISEMENT: 184 opt_type = ND_OPT_TARGET_LL_ADDR; 185 break; 186 case NDISC_ROUTER_SOLICITATION: 187 case NDISC_NEIGHBOUR_SOLICITATION: 188 opt_type = ND_OPT_SOURCE_LL_ADDR; 189 break; 190 default: 191 return; 192 } 193 194 wpan_dev = lowpan_802154_dev(dev)->wdev->ieee802154_ptr; 195 196 if (lowpan_802154_is_valid_src_short_addr(wpan_dev->short_addr)) { 197 ieee802154_le16_to_be16(&short_addr, 198 &wpan_dev->short_addr); 199 __ndisc_fill_addr_option(skb, opt_type, &short_addr, 200 IEEE802154_SHORT_ADDR_LEN, 0); 201 } 202 } 203 204 static void lowpan_ndisc_prefix_rcv_add_addr(struct net *net, 205 struct net_device *dev, 206 const struct prefix_info *pinfo, 207 struct inet6_dev *in6_dev, 208 struct in6_addr *addr, 209 int addr_type, u32 addr_flags, 210 bool sllao, bool tokenized, 211 __u32 valid_lft, 212 u32 prefered_lft, 213 bool dev_addr_generated) 214 { 215 int err; 216 217 /* generates short based address for RA PIO's */ 218 if (lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154) && dev_addr_generated && 219 !addrconf_ifid_802154_6lowpan(addr->s6_addr + 8, dev)) { 220 err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, 221 addr, addr_type, addr_flags, 222 sllao, tokenized, valid_lft, 223 prefered_lft); 224 if (err) 225 ND_PRINTK(2, warn, 226 "RA: could not add a short address based address for prefix: %pI6c\n", 227 &pinfo->prefix); 228 } 229 } 230 #endif 231 232 const struct ndisc_ops lowpan_ndisc_ops = { 233 .is_useropt = lowpan_ndisc_is_useropt, 234 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN) 235 .parse_options = lowpan_ndisc_parse_options, 236 .update = lowpan_ndisc_update, 237 .opt_addr_space = lowpan_ndisc_opt_addr_space, 238 .fill_addr_option = lowpan_ndisc_fill_addr_option, 239 .prefix_rcv_add_addr = lowpan_ndisc_prefix_rcv_add_addr, 240 #endif 241 }; 242