/* * Copyright (C) 2007-2012 Siemens AG * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 * as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * Written by: * Pavel Smolenskiy <pavel.smolenskiy@gmail.com> * Maxim Gorbachyov <maxim.gorbachev@siemens.com> * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> * Alexander Smirnov <alex.bluesman.smirnov@gmail.com> */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/netdevice.h> #include <linux/crc-ccitt.h> #include <asm/unaligned.h> #include <net/mac802154.h> #include <net/ieee802154_netdev.h> #include <net/nl802154.h> #include "ieee802154_i.h" static int ieee802154_deliver_skb(struct sk_buff *skb) { skb->ip_summed = CHECKSUM_UNNECESSARY; skb->protocol = htons(ETH_P_IEEE802154); return netif_receive_skb(skb); } static int ieee802154_subif_frame(struct ieee802154_sub_if_data *sdata, struct sk_buff *skb, const struct ieee802154_hdr *hdr) { struct wpan_dev *wpan_dev = &sdata->wpan_dev; __le16 span, sshort; int rc; pr_debug("getting packet via slave interface %s\n", sdata->dev->name); span = wpan_dev->pan_id; sshort = wpan_dev->short_addr; switch (mac_cb(skb)->dest.mode) { case IEEE802154_ADDR_NONE: if (mac_cb(skb)->dest.mode != IEEE802154_ADDR_NONE) /* FIXME: check if we are PAN coordinator */ skb->pkt_type = PACKET_OTHERHOST; else /* ACK comes with both addresses empty */ skb->pkt_type = PACKET_HOST; break; case IEEE802154_ADDR_LONG: if (mac_cb(skb)->dest.pan_id != span && mac_cb(skb)->dest.pan_id != cpu_to_le16(IEEE802154_PANID_BROADCAST)) skb->pkt_type = PACKET_OTHERHOST; else if (mac_cb(skb)->dest.extended_addr == wpan_dev->extended_addr) skb->pkt_type = PACKET_HOST; else skb->pkt_type = PACKET_OTHERHOST; break; case IEEE802154_ADDR_SHORT: if (mac_cb(skb)->dest.pan_id != span && mac_cb(skb)->dest.pan_id != cpu_to_le16(IEEE802154_PANID_BROADCAST)) skb->pkt_type = PACKET_OTHERHOST; else if (mac_cb(skb)->dest.short_addr == sshort) skb->pkt_type = PACKET_HOST; else if (mac_cb(skb)->dest.short_addr == cpu_to_le16(IEEE802154_ADDR_BROADCAST)) skb->pkt_type = PACKET_BROADCAST; else skb->pkt_type = PACKET_OTHERHOST; break; default: pr_debug("invalid dest mode\n"); goto fail; } skb->dev = sdata->dev; /* TODO this should be moved after netif_receive_skb call, otherwise * wireshark will show a mac header with security fields and the * payload is already decrypted. */ rc = mac802154_llsec_decrypt(&sdata->sec, skb); if (rc) { pr_debug("decryption failed: %i\n", rc); goto fail; } sdata->dev->stats.rx_packets++; sdata->dev->stats.rx_bytes += skb->len; switch (mac_cb(skb)->type) { case IEEE802154_FC_TYPE_BEACON: case IEEE802154_FC_TYPE_ACK: case IEEE802154_FC_TYPE_MAC_CMD: goto fail; case IEEE802154_FC_TYPE_DATA: return ieee802154_deliver_skb(skb); default: pr_warn_ratelimited("ieee802154: bad frame received " "(type = %d)\n", mac_cb(skb)->type); goto fail; } fail: kfree_skb(skb); return NET_RX_DROP; } static void ieee802154_print_addr(const char *name, const struct ieee802154_addr *addr) { if (addr->mode == IEEE802154_ADDR_NONE) pr_debug("%s not present\n", name); pr_debug("%s PAN ID: %04x\n", name, le16_to_cpu(addr->pan_id)); if (addr->mode == IEEE802154_ADDR_SHORT) { pr_debug("%s is short: %04x\n", name, le16_to_cpu(addr->short_addr)); } else { u64 hw = swab64((__force u64)addr->extended_addr); pr_debug("%s is hardware: %8phC\n", name, &hw); } } static int ieee802154_parse_frame_start(struct sk_buff *skb, struct ieee802154_hdr *hdr) { int hlen; struct ieee802154_mac_cb *cb = mac_cb_init(skb); skb_reset_mac_header(skb); hlen = ieee802154_hdr_pull(skb, hdr); if (hlen < 0) return -EINVAL; skb->mac_len = hlen; pr_debug("fc: %04x dsn: %02x\n", le16_to_cpup((__le16 *)&hdr->fc), hdr->seq); cb->type = hdr->fc.type; cb->ackreq = hdr->fc.ack_request; cb->secen = hdr->fc.security_enabled; ieee802154_print_addr("destination", &hdr->dest); ieee802154_print_addr("source", &hdr->source); cb->source = hdr->source; cb->dest = hdr->dest; if (hdr->fc.security_enabled) { u64 key; pr_debug("seclevel %i\n", hdr->sec.level); switch (hdr->sec.key_id_mode) { case IEEE802154_SCF_KEY_IMPLICIT: pr_debug("implicit key\n"); break; case IEEE802154_SCF_KEY_INDEX: pr_debug("key %02x\n", hdr->sec.key_id); break; case IEEE802154_SCF_KEY_SHORT_INDEX: pr_debug("key %04x:%04x %02x\n", le32_to_cpu(hdr->sec.short_src) >> 16, le32_to_cpu(hdr->sec.short_src) & 0xffff, hdr->sec.key_id); break; case IEEE802154_SCF_KEY_HW_INDEX: key = swab64((__force u64)hdr->sec.extended_src); pr_debug("key source %8phC %02x\n", &key, hdr->sec.key_id); break; } } return 0; } static void __ieee802154_rx_handle_packet(struct ieee802154_local *local, struct sk_buff *skb) { int ret; struct ieee802154_sub_if_data *sdata; struct ieee802154_hdr hdr; ret = ieee802154_parse_frame_start(skb, &hdr); if (ret) { pr_debug("got invalid frame\n"); kfree_skb(skb); return; } list_for_each_entry_rcu(sdata, &local->interfaces, list) { if (sdata->wpan_dev.iftype != NL802154_IFTYPE_NODE) continue; if (!ieee802154_sdata_running(sdata)) continue; ieee802154_subif_frame(sdata, skb, &hdr); skb = NULL; break; } kfree_skb(skb); } static void ieee802154_monitors_rx(struct ieee802154_local *local, struct sk_buff *skb) { struct sk_buff *skb2; struct ieee802154_sub_if_data *sdata; skb_reset_mac_header(skb); skb->ip_summed = CHECKSUM_UNNECESSARY; skb->pkt_type = PACKET_OTHERHOST; skb->protocol = htons(ETH_P_IEEE802154); list_for_each_entry_rcu(sdata, &local->interfaces, list) { if (sdata->wpan_dev.iftype != NL802154_IFTYPE_MONITOR) continue; if (!ieee802154_sdata_running(sdata)) continue; skb2 = skb_clone(skb, GFP_ATOMIC); if (skb2) { skb2->dev = sdata->dev; ieee802154_deliver_skb(skb2); sdata->dev->stats.rx_packets++; sdata->dev->stats.rx_bytes += skb->len; } } } void ieee802154_rx(struct ieee802154_local *local, struct sk_buff *skb) { u16 crc; WARN_ON_ONCE(softirq_count() == 0); if (local->suspended) goto drop; /* TODO: When a transceiver omits the checksum here, we * add an own calculated one. This is currently an ugly * solution because the monitor needs a crc here. */ if (local->hw.flags & IEEE802154_HW_RX_OMIT_CKSUM) { crc = crc_ccitt(0, skb->data, skb->len); put_unaligned_le16(crc, skb_put(skb, 2)); } rcu_read_lock(); ieee802154_monitors_rx(local, skb); /* Check if transceiver doesn't validate the checksum. * If not we validate the checksum here. */ if (local->hw.flags & IEEE802154_HW_RX_DROP_BAD_CKSUM) { crc = crc_ccitt(0, skb->data, skb->len); if (crc) { rcu_read_unlock(); goto drop; } } /* remove crc */ skb_trim(skb, skb->len - 2); __ieee802154_rx_handle_packet(local, skb); rcu_read_unlock(); return; drop: kfree_skb(skb); } void ieee802154_rx_irqsafe(struct ieee802154_hw *hw, struct sk_buff *skb, u8 lqi) { struct ieee802154_local *local = hw_to_local(hw); mac_cb(skb)->lqi = lqi; skb->pkt_type = IEEE802154_RX_MSG; skb_queue_tail(&local->skb_queue, skb); tasklet_schedule(&local->tasklet); } EXPORT_SYMBOL(ieee802154_rx_irqsafe);