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/rtnetlink.h> 29 #include <linux/nl802154.h> 30 31 #include "ieee802154_i.h" 32 33 static int ieee802154_deliver_skb(struct sk_buff *skb) 34 { 35 skb->ip_summed = CHECKSUM_UNNECESSARY; 36 skb->protocol = htons(ETH_P_IEEE802154); 37 38 return netif_receive_skb(skb); 39 } 40 41 static int 42 ieee802154_subif_frame(struct ieee802154_sub_if_data *sdata, 43 struct sk_buff *skb, const struct ieee802154_hdr *hdr) 44 { 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 = sdata->pan_id; 53 sshort = sdata->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 == sdata->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 kfree_skb(skb); 89 return NET_RX_DROP; 90 } 91 92 spin_unlock_bh(&sdata->mib_lock); 93 94 skb->dev = sdata->dev; 95 96 rc = mac802154_llsec_decrypt(&sdata->sec, skb); 97 if (rc) { 98 pr_debug("decryption failed: %i\n", rc); 99 goto fail; 100 } 101 102 sdata->dev->stats.rx_packets++; 103 sdata->dev->stats.rx_bytes += skb->len; 104 105 switch (mac_cb(skb)->type) { 106 case IEEE802154_FC_TYPE_DATA: 107 return ieee802154_deliver_skb(skb); 108 default: 109 pr_warn("ieee802154: bad frame received (type = %d)\n", 110 mac_cb(skb)->type); 111 goto fail; 112 } 113 114 fail: 115 kfree_skb(skb); 116 return NET_RX_DROP; 117 } 118 119 static void 120 ieee802154_print_addr(const char *name, const struct ieee802154_addr *addr) 121 { 122 if (addr->mode == IEEE802154_ADDR_NONE) 123 pr_debug("%s not present\n", name); 124 125 pr_debug("%s PAN ID: %04x\n", name, le16_to_cpu(addr->pan_id)); 126 if (addr->mode == IEEE802154_ADDR_SHORT) { 127 pr_debug("%s is short: %04x\n", name, 128 le16_to_cpu(addr->short_addr)); 129 } else { 130 u64 hw = swab64((__force u64)addr->extended_addr); 131 132 pr_debug("%s is hardware: %8phC\n", name, &hw); 133 } 134 } 135 136 static int 137 ieee802154_parse_frame_start(struct sk_buff *skb, struct ieee802154_hdr *hdr) 138 { 139 int hlen; 140 struct ieee802154_mac_cb *cb = mac_cb_init(skb); 141 142 skb_reset_mac_header(skb); 143 144 hlen = ieee802154_hdr_pull(skb, hdr); 145 if (hlen < 0) 146 return -EINVAL; 147 148 skb->mac_len = hlen; 149 150 pr_debug("fc: %04x dsn: %02x\n", le16_to_cpup((__le16 *)&hdr->fc), 151 hdr->seq); 152 153 cb->type = hdr->fc.type; 154 cb->ackreq = hdr->fc.ack_request; 155 cb->secen = hdr->fc.security_enabled; 156 157 ieee802154_print_addr("destination", &hdr->dest); 158 ieee802154_print_addr("source", &hdr->source); 159 160 cb->source = hdr->source; 161 cb->dest = hdr->dest; 162 163 if (hdr->fc.security_enabled) { 164 u64 key; 165 166 pr_debug("seclevel %i\n", hdr->sec.level); 167 168 switch (hdr->sec.key_id_mode) { 169 case IEEE802154_SCF_KEY_IMPLICIT: 170 pr_debug("implicit key\n"); 171 break; 172 173 case IEEE802154_SCF_KEY_INDEX: 174 pr_debug("key %02x\n", hdr->sec.key_id); 175 break; 176 177 case IEEE802154_SCF_KEY_SHORT_INDEX: 178 pr_debug("key %04x:%04x %02x\n", 179 le32_to_cpu(hdr->sec.short_src) >> 16, 180 le32_to_cpu(hdr->sec.short_src) & 0xffff, 181 hdr->sec.key_id); 182 break; 183 184 case IEEE802154_SCF_KEY_HW_INDEX: 185 key = swab64((__force u64)hdr->sec.extended_src); 186 pr_debug("key source %8phC %02x\n", &key, 187 hdr->sec.key_id); 188 break; 189 } 190 } 191 192 return 0; 193 } 194 195 static void 196 __ieee802154_rx_handle_packet(struct ieee802154_local *local, 197 struct sk_buff *skb) 198 { 199 int ret; 200 struct ieee802154_sub_if_data *sdata; 201 struct ieee802154_hdr hdr; 202 203 ret = ieee802154_parse_frame_start(skb, &hdr); 204 if (ret) { 205 pr_debug("got invalid frame\n"); 206 kfree_skb(skb); 207 return; 208 } 209 210 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 211 if (sdata->type != IEEE802154_DEV_WPAN || 212 !netif_running(sdata->dev)) 213 continue; 214 215 ieee802154_subif_frame(sdata, skb, &hdr); 216 skb = NULL; 217 break; 218 } 219 220 if (skb) 221 kfree_skb(skb); 222 } 223 224 static void 225 ieee802154_monitors_rx(struct ieee802154_local *local, struct sk_buff *skb) 226 { 227 struct sk_buff *skb2; 228 struct ieee802154_sub_if_data *sdata; 229 230 skb_reset_mac_header(skb); 231 skb->ip_summed = CHECKSUM_UNNECESSARY; 232 skb->pkt_type = PACKET_OTHERHOST; 233 skb->protocol = htons(ETH_P_IEEE802154); 234 235 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 236 if (sdata->type != IEEE802154_DEV_MONITOR || 237 !netif_running(sdata->dev)) 238 continue; 239 240 skb2 = skb_clone(skb, GFP_ATOMIC); 241 skb2->dev = sdata->dev; 242 243 ieee802154_deliver_skb(skb2); 244 } 245 } 246 247 void ieee802154_rx(struct ieee802154_hw *hw, struct sk_buff *skb) 248 { 249 struct ieee802154_local *local = hw_to_local(hw); 250 u16 crc; 251 252 WARN_ON_ONCE(softirq_count() == 0); 253 254 /* TODO: When a transceiver omits the checksum here, we 255 * add an own calculated one. This is currently an ugly 256 * solution because the monitor needs a crc here. 257 */ 258 if (local->hw.flags & IEEE802154_HW_RX_OMIT_CKSUM) { 259 crc = crc_ccitt(0, skb->data, skb->len); 260 put_unaligned_le16(crc, skb_put(skb, 2)); 261 } 262 263 rcu_read_lock(); 264 265 ieee802154_monitors_rx(local, skb); 266 267 /* Check if transceiver doesn't validate the checksum. 268 * If not we validate the checksum here. 269 */ 270 if (local->hw.flags & IEEE802154_HW_RX_DROP_BAD_CKSUM) { 271 crc = crc_ccitt(0, skb->data, skb->len); 272 if (crc) { 273 rcu_read_unlock(); 274 kfree_skb(skb); 275 return; 276 } 277 } 278 /* remove crc */ 279 skb_trim(skb, skb->len - 2); 280 281 __ieee802154_rx_handle_packet(local, skb); 282 283 rcu_read_unlock(); 284 } 285 EXPORT_SYMBOL(ieee802154_rx); 286 287 void 288 ieee802154_rx_irqsafe(struct ieee802154_hw *hw, struct sk_buff *skb, u8 lqi) 289 { 290 struct ieee802154_local *local = hw_to_local(hw); 291 292 mac_cb(skb)->lqi = lqi; 293 skb->pkt_type = IEEE802154_RX_MSG; 294 skb_queue_tail(&local->skb_queue, skb); 295 tasklet_schedule(&local->tasklet); 296 } 297 EXPORT_SYMBOL(ieee802154_rx_irqsafe); 298