1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2007-2012 Siemens AG 4 * 5 * Written by: 6 * Pavel Smolenskiy <pavel.smolenskiy@gmail.com> 7 * Maxim Gorbachyov <maxim.gorbachev@siemens.com> 8 * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> 9 * Alexander Smirnov <alex.bluesman.smirnov@gmail.com> 10 */ 11 12 #include <linux/kernel.h> 13 #include <linux/module.h> 14 #include <linux/netdevice.h> 15 #include <linux/crc-ccitt.h> 16 #include <asm/unaligned.h> 17 18 #include <net/mac802154.h> 19 #include <net/ieee802154_netdev.h> 20 #include <net/nl802154.h> 21 22 #include "ieee802154_i.h" 23 24 static int ieee802154_deliver_skb(struct sk_buff *skb) 25 { 26 skb->ip_summed = CHECKSUM_UNNECESSARY; 27 skb->protocol = htons(ETH_P_IEEE802154); 28 29 return netif_receive_skb(skb); 30 } 31 32 static int 33 ieee802154_subif_frame(struct ieee802154_sub_if_data *sdata, 34 struct sk_buff *skb, const struct ieee802154_hdr *hdr) 35 { 36 struct wpan_dev *wpan_dev = &sdata->wpan_dev; 37 __le16 span, sshort; 38 int rc; 39 40 pr_debug("getting packet via slave interface %s\n", sdata->dev->name); 41 42 span = wpan_dev->pan_id; 43 sshort = wpan_dev->short_addr; 44 45 switch (mac_cb(skb)->dest.mode) { 46 case IEEE802154_ADDR_NONE: 47 if (mac_cb(skb)->dest.mode != IEEE802154_ADDR_NONE) 48 /* FIXME: check if we are PAN coordinator */ 49 skb->pkt_type = PACKET_OTHERHOST; 50 else 51 /* ACK comes with both addresses empty */ 52 skb->pkt_type = PACKET_HOST; 53 break; 54 case IEEE802154_ADDR_LONG: 55 if (mac_cb(skb)->dest.pan_id != span && 56 mac_cb(skb)->dest.pan_id != cpu_to_le16(IEEE802154_PANID_BROADCAST)) 57 skb->pkt_type = PACKET_OTHERHOST; 58 else if (mac_cb(skb)->dest.extended_addr == wpan_dev->extended_addr) 59 skb->pkt_type = PACKET_HOST; 60 else 61 skb->pkt_type = PACKET_OTHERHOST; 62 break; 63 case IEEE802154_ADDR_SHORT: 64 if (mac_cb(skb)->dest.pan_id != span && 65 mac_cb(skb)->dest.pan_id != cpu_to_le16(IEEE802154_PANID_BROADCAST)) 66 skb->pkt_type = PACKET_OTHERHOST; 67 else if (mac_cb(skb)->dest.short_addr == sshort) 68 skb->pkt_type = PACKET_HOST; 69 else if (mac_cb(skb)->dest.short_addr == 70 cpu_to_le16(IEEE802154_ADDR_BROADCAST)) 71 skb->pkt_type = PACKET_BROADCAST; 72 else 73 skb->pkt_type = PACKET_OTHERHOST; 74 break; 75 default: 76 pr_debug("invalid dest mode\n"); 77 goto fail; 78 } 79 80 skb->dev = sdata->dev; 81 82 /* TODO this should be moved after netif_receive_skb call, otherwise 83 * wireshark will show a mac header with security fields and the 84 * payload is already decrypted. 85 */ 86 rc = mac802154_llsec_decrypt(&sdata->sec, skb); 87 if (rc) { 88 pr_debug("decryption failed: %i\n", rc); 89 goto fail; 90 } 91 92 sdata->dev->stats.rx_packets++; 93 sdata->dev->stats.rx_bytes += skb->len; 94 95 switch (mac_cb(skb)->type) { 96 case IEEE802154_FC_TYPE_BEACON: 97 case IEEE802154_FC_TYPE_ACK: 98 case IEEE802154_FC_TYPE_MAC_CMD: 99 goto fail; 100 101 case IEEE802154_FC_TYPE_DATA: 102 return ieee802154_deliver_skb(skb); 103 default: 104 pr_warn_ratelimited("ieee802154: bad frame received " 105 "(type = %d)\n", mac_cb(skb)->type); 106 goto fail; 107 } 108 109 fail: 110 kfree_skb(skb); 111 return NET_RX_DROP; 112 } 113 114 static void 115 ieee802154_print_addr(const char *name, const struct ieee802154_addr *addr) 116 { 117 if (addr->mode == IEEE802154_ADDR_NONE) 118 pr_debug("%s not present\n", name); 119 120 pr_debug("%s PAN ID: %04x\n", name, le16_to_cpu(addr->pan_id)); 121 if (addr->mode == IEEE802154_ADDR_SHORT) { 122 pr_debug("%s is short: %04x\n", name, 123 le16_to_cpu(addr->short_addr)); 124 } else { 125 u64 hw = swab64((__force u64)addr->extended_addr); 126 127 pr_debug("%s is hardware: %8phC\n", name, &hw); 128 } 129 } 130 131 static int 132 ieee802154_parse_frame_start(struct sk_buff *skb, struct ieee802154_hdr *hdr) 133 { 134 int hlen; 135 struct ieee802154_mac_cb *cb = mac_cb_init(skb); 136 137 skb_reset_mac_header(skb); 138 139 hlen = ieee802154_hdr_pull(skb, hdr); 140 if (hlen < 0) 141 return -EINVAL; 142 143 skb->mac_len = hlen; 144 145 pr_debug("fc: %04x dsn: %02x\n", le16_to_cpup((__le16 *)&hdr->fc), 146 hdr->seq); 147 148 cb->type = hdr->fc.type; 149 cb->ackreq = hdr->fc.ack_request; 150 cb->secen = hdr->fc.security_enabled; 151 152 ieee802154_print_addr("destination", &hdr->dest); 153 ieee802154_print_addr("source", &hdr->source); 154 155 cb->source = hdr->source; 156 cb->dest = hdr->dest; 157 158 if (hdr->fc.security_enabled) { 159 u64 key; 160 161 pr_debug("seclevel %i\n", hdr->sec.level); 162 163 switch (hdr->sec.key_id_mode) { 164 case IEEE802154_SCF_KEY_IMPLICIT: 165 pr_debug("implicit key\n"); 166 break; 167 168 case IEEE802154_SCF_KEY_INDEX: 169 pr_debug("key %02x\n", hdr->sec.key_id); 170 break; 171 172 case IEEE802154_SCF_KEY_SHORT_INDEX: 173 pr_debug("key %04x:%04x %02x\n", 174 le32_to_cpu(hdr->sec.short_src) >> 16, 175 le32_to_cpu(hdr->sec.short_src) & 0xffff, 176 hdr->sec.key_id); 177 break; 178 179 case IEEE802154_SCF_KEY_HW_INDEX: 180 key = swab64((__force u64)hdr->sec.extended_src); 181 pr_debug("key source %8phC %02x\n", &key, 182 hdr->sec.key_id); 183 break; 184 } 185 } 186 187 return 0; 188 } 189 190 static void 191 __ieee802154_rx_handle_packet(struct ieee802154_local *local, 192 struct sk_buff *skb) 193 { 194 int ret; 195 struct ieee802154_sub_if_data *sdata; 196 struct ieee802154_hdr hdr; 197 198 ret = ieee802154_parse_frame_start(skb, &hdr); 199 if (ret) { 200 pr_debug("got invalid frame\n"); 201 kfree_skb(skb); 202 return; 203 } 204 205 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 206 if (sdata->wpan_dev.iftype != NL802154_IFTYPE_NODE) 207 continue; 208 209 if (!ieee802154_sdata_running(sdata)) 210 continue; 211 212 ieee802154_subif_frame(sdata, skb, &hdr); 213 skb = NULL; 214 break; 215 } 216 217 kfree_skb(skb); 218 } 219 220 static void 221 ieee802154_monitors_rx(struct ieee802154_local *local, struct sk_buff *skb) 222 { 223 struct sk_buff *skb2; 224 struct ieee802154_sub_if_data *sdata; 225 226 skb_reset_mac_header(skb); 227 skb->ip_summed = CHECKSUM_UNNECESSARY; 228 skb->pkt_type = PACKET_OTHERHOST; 229 skb->protocol = htons(ETH_P_IEEE802154); 230 231 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 232 if (sdata->wpan_dev.iftype != NL802154_IFTYPE_MONITOR) 233 continue; 234 235 if (!ieee802154_sdata_running(sdata)) 236 continue; 237 238 skb2 = skb_clone(skb, GFP_ATOMIC); 239 if (skb2) { 240 skb2->dev = sdata->dev; 241 ieee802154_deliver_skb(skb2); 242 243 sdata->dev->stats.rx_packets++; 244 sdata->dev->stats.rx_bytes += skb->len; 245 } 246 } 247 } 248 249 void ieee802154_rx(struct ieee802154_local *local, struct sk_buff *skb) 250 { 251 u16 crc; 252 253 WARN_ON_ONCE(softirq_count() == 0); 254 255 if (local->suspended) 256 goto drop; 257 258 /* TODO: When a transceiver omits the checksum here, we 259 * add an own calculated one. This is currently an ugly 260 * solution because the monitor needs a crc here. 261 */ 262 if (local->hw.flags & IEEE802154_HW_RX_OMIT_CKSUM) { 263 crc = crc_ccitt(0, skb->data, skb->len); 264 put_unaligned_le16(crc, skb_put(skb, 2)); 265 } 266 267 rcu_read_lock(); 268 269 ieee802154_monitors_rx(local, skb); 270 271 /* Check if transceiver doesn't validate the checksum. 272 * If not we validate the checksum here. 273 */ 274 if (local->hw.flags & IEEE802154_HW_RX_DROP_BAD_CKSUM) { 275 crc = crc_ccitt(0, skb->data, skb->len); 276 if (crc) { 277 rcu_read_unlock(); 278 goto drop; 279 } 280 } 281 /* remove crc */ 282 skb_trim(skb, skb->len - 2); 283 284 __ieee802154_rx_handle_packet(local, skb); 285 286 rcu_read_unlock(); 287 288 return; 289 drop: 290 kfree_skb(skb); 291 } 292 293 void 294 ieee802154_rx_irqsafe(struct ieee802154_hw *hw, struct sk_buff *skb, u8 lqi) 295 { 296 struct ieee802154_local *local = hw_to_local(hw); 297 298 mac_cb(skb)->lqi = lqi; 299 skb->pkt_type = IEEE802154_RX_MSG; 300 skb_queue_tail(&local->skb_queue, skb); 301 tasklet_schedule(&local->tasklet); 302 } 303 EXPORT_SYMBOL(ieee802154_rx_irqsafe); 304