1 /* 2 * Copyright (C) 2007-2012 Siemens AG 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 6 * as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11 * GNU General Public License for more details. 12 * 13 * Written by: 14 * Pavel Smolenskiy <pavel.smolenskiy@gmail.com> 15 * Maxim Gorbachyov <maxim.gorbachev@siemens.com> 16 * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> 17 * Alexander Smirnov <alex.bluesman.smirnov@gmail.com> 18 */ 19 20 #include <linux/kernel.h> 21 #include <linux/module.h> 22 #include <linux/netdevice.h> 23 #include <linux/crc-ccitt.h> 24 #include <asm/unaligned.h> 25 26 #include <net/mac802154.h> 27 #include <net/ieee802154_netdev.h> 28 #include <net/nl802154.h> 29 30 #include "ieee802154_i.h" 31 32 static int ieee802154_deliver_skb(struct sk_buff *skb) 33 { 34 skb->ip_summed = CHECKSUM_UNNECESSARY; 35 skb->protocol = htons(ETH_P_IEEE802154); 36 37 return netif_receive_skb(skb); 38 } 39 40 static int 41 ieee802154_subif_frame(struct ieee802154_sub_if_data *sdata, 42 struct sk_buff *skb, const struct ieee802154_hdr *hdr) 43 { 44 struct wpan_dev *wpan_dev = &sdata->wpan_dev; 45 __le16 span, sshort; 46 int rc; 47 48 pr_debug("getting packet via slave interface %s\n", sdata->dev->name); 49 50 spin_lock_bh(&sdata->mib_lock); 51 52 span = wpan_dev->pan_id; 53 sshort = wpan_dev->short_addr; 54 55 switch (mac_cb(skb)->dest.mode) { 56 case IEEE802154_ADDR_NONE: 57 if (mac_cb(skb)->dest.mode != IEEE802154_ADDR_NONE) 58 /* FIXME: check if we are PAN coordinator */ 59 skb->pkt_type = PACKET_OTHERHOST; 60 else 61 /* ACK comes with both addresses empty */ 62 skb->pkt_type = PACKET_HOST; 63 break; 64 case IEEE802154_ADDR_LONG: 65 if (mac_cb(skb)->dest.pan_id != span && 66 mac_cb(skb)->dest.pan_id != cpu_to_le16(IEEE802154_PANID_BROADCAST)) 67 skb->pkt_type = PACKET_OTHERHOST; 68 else if (mac_cb(skb)->dest.extended_addr == wpan_dev->extended_addr) 69 skb->pkt_type = PACKET_HOST; 70 else 71 skb->pkt_type = PACKET_OTHERHOST; 72 break; 73 case IEEE802154_ADDR_SHORT: 74 if (mac_cb(skb)->dest.pan_id != span && 75 mac_cb(skb)->dest.pan_id != cpu_to_le16(IEEE802154_PANID_BROADCAST)) 76 skb->pkt_type = PACKET_OTHERHOST; 77 else if (mac_cb(skb)->dest.short_addr == sshort) 78 skb->pkt_type = PACKET_HOST; 79 else if (mac_cb(skb)->dest.short_addr == 80 cpu_to_le16(IEEE802154_ADDR_BROADCAST)) 81 skb->pkt_type = PACKET_BROADCAST; 82 else 83 skb->pkt_type = PACKET_OTHERHOST; 84 break; 85 default: 86 spin_unlock_bh(&sdata->mib_lock); 87 pr_debug("invalid dest mode\n"); 88 goto fail; 89 } 90 91 spin_unlock_bh(&sdata->mib_lock); 92 93 skb->dev = sdata->dev; 94 95 rc = mac802154_llsec_decrypt(&sdata->sec, skb); 96 if (rc) { 97 pr_debug("decryption failed: %i\n", rc); 98 goto fail; 99 } 100 101 sdata->dev->stats.rx_packets++; 102 sdata->dev->stats.rx_bytes += skb->len; 103 104 switch (mac_cb(skb)->type) { 105 case IEEE802154_FC_TYPE_DATA: 106 return ieee802154_deliver_skb(skb); 107 default: 108 pr_warn("ieee802154: bad frame received (type = %d)\n", 109 mac_cb(skb)->type); 110 goto fail; 111 } 112 113 fail: 114 kfree_skb(skb); 115 return NET_RX_DROP; 116 } 117 118 static void 119 ieee802154_print_addr(const char *name, const struct ieee802154_addr *addr) 120 { 121 if (addr->mode == IEEE802154_ADDR_NONE) 122 pr_debug("%s not present\n", name); 123 124 pr_debug("%s PAN ID: %04x\n", name, le16_to_cpu(addr->pan_id)); 125 if (addr->mode == IEEE802154_ADDR_SHORT) { 126 pr_debug("%s is short: %04x\n", name, 127 le16_to_cpu(addr->short_addr)); 128 } else { 129 u64 hw = swab64((__force u64)addr->extended_addr); 130 131 pr_debug("%s is hardware: %8phC\n", name, &hw); 132 } 133 } 134 135 static int 136 ieee802154_parse_frame_start(struct sk_buff *skb, struct ieee802154_hdr *hdr) 137 { 138 int hlen; 139 struct ieee802154_mac_cb *cb = mac_cb_init(skb); 140 141 skb_reset_mac_header(skb); 142 143 hlen = ieee802154_hdr_pull(skb, hdr); 144 if (hlen < 0) 145 return -EINVAL; 146 147 skb->mac_len = hlen; 148 149 pr_debug("fc: %04x dsn: %02x\n", le16_to_cpup((__le16 *)&hdr->fc), 150 hdr->seq); 151 152 cb->type = hdr->fc.type; 153 cb->ackreq = hdr->fc.ack_request; 154 cb->secen = hdr->fc.security_enabled; 155 156 ieee802154_print_addr("destination", &hdr->dest); 157 ieee802154_print_addr("source", &hdr->source); 158 159 cb->source = hdr->source; 160 cb->dest = hdr->dest; 161 162 if (hdr->fc.security_enabled) { 163 u64 key; 164 165 pr_debug("seclevel %i\n", hdr->sec.level); 166 167 switch (hdr->sec.key_id_mode) { 168 case IEEE802154_SCF_KEY_IMPLICIT: 169 pr_debug("implicit key\n"); 170 break; 171 172 case IEEE802154_SCF_KEY_INDEX: 173 pr_debug("key %02x\n", hdr->sec.key_id); 174 break; 175 176 case IEEE802154_SCF_KEY_SHORT_INDEX: 177 pr_debug("key %04x:%04x %02x\n", 178 le32_to_cpu(hdr->sec.short_src) >> 16, 179 le32_to_cpu(hdr->sec.short_src) & 0xffff, 180 hdr->sec.key_id); 181 break; 182 183 case IEEE802154_SCF_KEY_HW_INDEX: 184 key = swab64((__force u64)hdr->sec.extended_src); 185 pr_debug("key source %8phC %02x\n", &key, 186 hdr->sec.key_id); 187 break; 188 } 189 } 190 191 return 0; 192 } 193 194 static void 195 __ieee802154_rx_handle_packet(struct ieee802154_local *local, 196 struct sk_buff *skb) 197 { 198 int ret; 199 struct ieee802154_sub_if_data *sdata; 200 struct ieee802154_hdr hdr; 201 202 ret = ieee802154_parse_frame_start(skb, &hdr); 203 if (ret) { 204 pr_debug("got invalid frame\n"); 205 kfree_skb(skb); 206 return; 207 } 208 209 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 210 if (sdata->vif.type != NL802154_IFTYPE_NODE || 211 !netif_running(sdata->dev)) 212 continue; 213 214 ieee802154_subif_frame(sdata, skb, &hdr); 215 skb = NULL; 216 break; 217 } 218 219 if (skb) 220 kfree_skb(skb); 221 } 222 223 static void 224 ieee802154_monitors_rx(struct ieee802154_local *local, struct sk_buff *skb) 225 { 226 struct sk_buff *skb2; 227 struct ieee802154_sub_if_data *sdata; 228 229 skb_reset_mac_header(skb); 230 skb->ip_summed = CHECKSUM_UNNECESSARY; 231 skb->pkt_type = PACKET_OTHERHOST; 232 skb->protocol = htons(ETH_P_IEEE802154); 233 234 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 235 if (sdata->vif.type != NL802154_IFTYPE_MONITOR) 236 continue; 237 238 if (!ieee802154_sdata_running(sdata)) 239 continue; 240 241 skb2 = skb_clone(skb, GFP_ATOMIC); 242 if (skb2) { 243 skb2->dev = sdata->dev; 244 ieee802154_deliver_skb(skb2); 245 246 sdata->dev->stats.rx_packets++; 247 sdata->dev->stats.rx_bytes += skb->len; 248 } 249 } 250 } 251 252 void ieee802154_rx(struct ieee802154_hw *hw, struct sk_buff *skb) 253 { 254 struct ieee802154_local *local = hw_to_local(hw); 255 u16 crc; 256 257 WARN_ON_ONCE(softirq_count() == 0); 258 259 /* TODO: When a transceiver omits the checksum here, we 260 * add an own calculated one. This is currently an ugly 261 * solution because the monitor needs a crc here. 262 */ 263 if (local->hw.flags & IEEE802154_HW_RX_OMIT_CKSUM) { 264 crc = crc_ccitt(0, skb->data, skb->len); 265 put_unaligned_le16(crc, skb_put(skb, 2)); 266 } 267 268 rcu_read_lock(); 269 270 ieee802154_monitors_rx(local, skb); 271 272 /* Check if transceiver doesn't validate the checksum. 273 * If not we validate the checksum here. 274 */ 275 if (local->hw.flags & IEEE802154_HW_RX_DROP_BAD_CKSUM) { 276 crc = crc_ccitt(0, skb->data, skb->len); 277 if (crc) { 278 rcu_read_unlock(); 279 kfree_skb(skb); 280 return; 281 } 282 } 283 /* remove crc */ 284 skb_trim(skb, skb->len - 2); 285 286 __ieee802154_rx_handle_packet(local, skb); 287 288 rcu_read_unlock(); 289 } 290 EXPORT_SYMBOL(ieee802154_rx); 291 292 void 293 ieee802154_rx_irqsafe(struct ieee802154_hw *hw, struct sk_buff *skb, u8 lqi) 294 { 295 struct ieee802154_local *local = hw_to_local(hw); 296 297 mac_cb(skb)->lqi = lqi; 298 skb->pkt_type = IEEE802154_RX_MSG; 299 skb_queue_tail(&local->skb_queue, skb); 300 tasklet_schedule(&local->tasklet); 301 } 302 EXPORT_SYMBOL(ieee802154_rx_irqsafe); 303