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 switch (nd_opt->nd_opt_type) { 51 case ND_OPT_SOURCE_LL_ADDR: 52 case ND_OPT_TARGET_LL_ADDR: 53 return lowpan_ndisc_parse_802154_options(dev, nd_opt, ndopts); 54 default: 55 return 0; 56 } 57 } 58 59 static void lowpan_ndisc_802154_update(struct neighbour *n, u32 flags, 60 u8 icmp6_type, 61 const struct ndisc_options *ndopts) 62 { 63 struct lowpan_802154_neigh *neigh = lowpan_802154_neigh(neighbour_priv(n)); 64 u8 *lladdr_short = NULL; 65 66 switch (icmp6_type) { 67 case NDISC_ROUTER_SOLICITATION: 68 case NDISC_ROUTER_ADVERTISEMENT: 69 case NDISC_NEIGHBOUR_SOLICITATION: 70 if (ndopts->nd_802154_opts_src_lladdr) { 71 lladdr_short = __ndisc_opt_addr_data(ndopts->nd_802154_opts_src_lladdr, 72 IEEE802154_SHORT_ADDR_LEN, 0); 73 if (!lladdr_short) { 74 ND_PRINTK(2, warn, 75 "NA: invalid short link-layer address length\n"); 76 return; 77 } 78 } 79 break; 80 case NDISC_REDIRECT: 81 case NDISC_NEIGHBOUR_ADVERTISEMENT: 82 if (ndopts->nd_802154_opts_tgt_lladdr) { 83 lladdr_short = __ndisc_opt_addr_data(ndopts->nd_802154_opts_tgt_lladdr, 84 IEEE802154_SHORT_ADDR_LEN, 0); 85 if (!lladdr_short) { 86 ND_PRINTK(2, warn, 87 "NA: invalid short link-layer address length\n"); 88 return; 89 } 90 } 91 break; 92 default: 93 break; 94 } 95 96 write_lock_bh(&n->lock); 97 if (lladdr_short) 98 ieee802154_be16_to_le16(&neigh->short_addr, lladdr_short); 99 else 100 neigh->short_addr = cpu_to_le16(IEEE802154_ADDR_SHORT_UNSPEC); 101 write_unlock_bh(&n->lock); 102 } 103 104 static void lowpan_ndisc_update(const struct net_device *dev, 105 struct neighbour *n, u32 flags, u8 icmp6_type, 106 const struct ndisc_options *ndopts) 107 { 108 if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154)) 109 return; 110 111 /* react on overrides only. TODO check if this is really right. */ 112 if (flags & NEIGH_UPDATE_F_OVERRIDE) 113 lowpan_ndisc_802154_update(n, flags, icmp6_type, ndopts); 114 } 115 116 static int lowpan_ndisc_opt_addr_space(const struct net_device *dev, 117 u8 icmp6_type, struct neighbour *neigh, 118 u8 *ha_buf, u8 **ha) 119 { 120 struct lowpan_802154_neigh *n; 121 struct wpan_dev *wpan_dev; 122 int addr_space = 0; 123 124 if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154)) 125 return 0; 126 127 switch (icmp6_type) { 128 case NDISC_REDIRECT: 129 n = lowpan_802154_neigh(neighbour_priv(neigh)); 130 131 read_lock_bh(&neigh->lock); 132 if (lowpan_802154_is_valid_src_short_addr(n->short_addr)) { 133 memcpy(ha_buf, &n->short_addr, 134 IEEE802154_SHORT_ADDR_LEN); 135 read_unlock_bh(&neigh->lock); 136 addr_space += __ndisc_opt_addr_space(IEEE802154_SHORT_ADDR_LEN, 0); 137 *ha = ha_buf; 138 } 139 read_unlock_bh(&neigh->lock); 140 break; 141 case NDISC_NEIGHBOUR_ADVERTISEMENT: 142 case NDISC_NEIGHBOUR_SOLICITATION: 143 case NDISC_ROUTER_SOLICITATION: 144 wpan_dev = lowpan_802154_dev(dev)->wdev->ieee802154_ptr; 145 146 if (lowpan_802154_is_valid_src_short_addr(wpan_dev->short_addr)) 147 addr_space = __ndisc_opt_addr_space(IEEE802154_SHORT_ADDR_LEN, 0); 148 break; 149 default: 150 break; 151 } 152 153 return addr_space; 154 } 155 156 static void lowpan_ndisc_fill_addr_option(const struct net_device *dev, 157 struct sk_buff *skb, u8 icmp6_type, 158 const u8 *ha) 159 { 160 struct wpan_dev *wpan_dev; 161 __be16 short_addr; 162 u8 opt_type; 163 164 if (!lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154)) 165 return; 166 167 switch (icmp6_type) { 168 case NDISC_REDIRECT: 169 if (ha) { 170 ieee802154_le16_to_be16(&short_addr, ha); 171 __ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR, 172 &short_addr, 173 IEEE802154_SHORT_ADDR_LEN, 0); 174 } 175 return; 176 case NDISC_NEIGHBOUR_ADVERTISEMENT: 177 opt_type = ND_OPT_TARGET_LL_ADDR; 178 break; 179 case NDISC_ROUTER_SOLICITATION: 180 case NDISC_NEIGHBOUR_SOLICITATION: 181 opt_type = ND_OPT_SOURCE_LL_ADDR; 182 break; 183 default: 184 return; 185 } 186 187 wpan_dev = lowpan_802154_dev(dev)->wdev->ieee802154_ptr; 188 189 if (lowpan_802154_is_valid_src_short_addr(wpan_dev->short_addr)) { 190 ieee802154_le16_to_be16(&short_addr, 191 &wpan_dev->short_addr); 192 __ndisc_fill_addr_option(skb, opt_type, &short_addr, 193 IEEE802154_SHORT_ADDR_LEN, 0); 194 } 195 } 196 197 static void lowpan_ndisc_prefix_rcv_add_addr(struct net *net, 198 struct net_device *dev, 199 const struct prefix_info *pinfo, 200 struct inet6_dev *in6_dev, 201 struct in6_addr *addr, 202 int addr_type, u32 addr_flags, 203 bool sllao, bool tokenized, 204 __u32 valid_lft, 205 u32 prefered_lft, 206 bool dev_addr_generated) 207 { 208 int err; 209 210 /* generates short based address for RA PIO's */ 211 if (lowpan_is_ll(dev, LOWPAN_LLTYPE_IEEE802154) && dev_addr_generated && 212 !addrconf_ifid_802154_6lowpan(addr->s6_addr + 8, dev)) { 213 err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, 214 addr, addr_type, addr_flags, 215 sllao, tokenized, valid_lft, 216 prefered_lft); 217 if (err) 218 ND_PRINTK(2, warn, 219 "RA: could not add a short address based address for prefix: %pI6c\n", 220 &pinfo->prefix); 221 } 222 } 223 #endif 224 225 const struct ndisc_ops lowpan_ndisc_ops = { 226 .is_useropt = lowpan_ndisc_is_useropt, 227 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN) 228 .parse_options = lowpan_ndisc_parse_options, 229 .update = lowpan_ndisc_update, 230 .opt_addr_space = lowpan_ndisc_opt_addr_space, 231 .fill_addr_option = lowpan_ndisc_fill_addr_option, 232 .prefix_rcv_add_addr = lowpan_ndisc_prefix_rcv_add_addr, 233 #endif 234 }; 235