diff options
Diffstat (limited to 'net/mac802154/rx.c')
-rw-r--r-- | net/mac802154/rx.c | 422 |
1 files changed, 422 insertions, 0 deletions
diff --git a/net/mac802154/rx.c b/net/mac802154/rx.c new file mode 100644 index 0000000000..e2434b4fe5 --- /dev/null +++ b/net/mac802154/rx.c @@ -0,0 +1,422 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2007-2012 Siemens AG + * + * 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); +} + +void mac802154_rx_beacon_worker(struct work_struct *work) +{ + struct ieee802154_local *local = + container_of(work, struct ieee802154_local, rx_beacon_work); + struct cfg802154_mac_pkt *mac_pkt; + + mac_pkt = list_first_entry_or_null(&local->rx_beacon_list, + struct cfg802154_mac_pkt, node); + if (!mac_pkt) + return; + + mac802154_process_beacon(local, mac_pkt->skb, mac_pkt->page, mac_pkt->channel); + + list_del(&mac_pkt->node); + kfree_skb(mac_pkt->skb); + kfree(mac_pkt); +} + +static bool mac802154_should_answer_beacon_req(struct ieee802154_local *local) +{ + struct cfg802154_beacon_request *beacon_req; + unsigned int interval; + + rcu_read_lock(); + beacon_req = rcu_dereference(local->beacon_req); + if (!beacon_req) { + rcu_read_unlock(); + return false; + } + + interval = beacon_req->interval; + rcu_read_unlock(); + + if (!mac802154_is_beaconing(local)) + return false; + + return interval == IEEE802154_ACTIVE_SCAN_DURATION; +} + +void mac802154_rx_mac_cmd_worker(struct work_struct *work) +{ + struct ieee802154_local *local = + container_of(work, struct ieee802154_local, rx_mac_cmd_work); + struct cfg802154_mac_pkt *mac_pkt; + u8 mac_cmd; + int rc; + + mac_pkt = list_first_entry_or_null(&local->rx_mac_cmd_list, + struct cfg802154_mac_pkt, node); + if (!mac_pkt) + return; + + rc = ieee802154_get_mac_cmd(mac_pkt->skb, &mac_cmd); + if (rc) + goto out; + + switch (mac_cmd) { + case IEEE802154_CMD_BEACON_REQ: + dev_dbg(&mac_pkt->sdata->dev->dev, "processing BEACON REQ\n"); + if (!mac802154_should_answer_beacon_req(local)) + break; + + queue_delayed_work(local->mac_wq, &local->beacon_work, 0); + break; + default: + break; + } + +out: + list_del(&mac_pkt->node); + kfree_skb(mac_pkt->skb); + kfree(mac_pkt); +} + +static int +ieee802154_subif_frame(struct ieee802154_sub_if_data *sdata, + struct sk_buff *skb, const struct ieee802154_hdr *hdr) +{ + struct wpan_phy *wpan_phy = sdata->local->hw.phy; + struct wpan_dev *wpan_dev = &sdata->wpan_dev; + struct cfg802154_mac_pkt *mac_pkt; + __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; + + /* Level 3 filtering: Only beacons are accepted during scans */ + if (sdata->required_filtering == IEEE802154_FILTERING_3_SCAN && + sdata->required_filtering > wpan_phy->filtering) { + if (mac_cb(skb)->type != IEEE802154_FC_TYPE_BEACON) { + dev_dbg(&sdata->dev->dev, + "drop non-beacon frame (0x%x) during scan\n", + mac_cb(skb)->type); + goto fail; + } + } + + switch (mac_cb(skb)->dest.mode) { + case IEEE802154_ADDR_NONE: + if (hdr->source.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: + dev_dbg(&sdata->dev->dev, "BEACON received\n"); + if (!mac802154_is_scanning(sdata->local)) + goto fail; + + mac_pkt = kzalloc(sizeof(*mac_pkt), GFP_ATOMIC); + if (!mac_pkt) + goto fail; + + mac_pkt->skb = skb_get(skb); + mac_pkt->sdata = sdata; + mac_pkt->page = sdata->local->scan_page; + mac_pkt->channel = sdata->local->scan_channel; + list_add_tail(&mac_pkt->node, &sdata->local->rx_beacon_list); + queue_work(sdata->local->mac_wq, &sdata->local->rx_beacon_work); + return NET_RX_SUCCESS; + + case IEEE802154_FC_TYPE_MAC_CMD: + dev_dbg(&sdata->dev->dev, "MAC COMMAND received\n"); + mac_pkt = kzalloc(sizeof(*mac_pkt), GFP_ATOMIC); + if (!mac_pkt) + goto fail; + + mac_pkt->skb = skb_get(skb); + mac_pkt->sdata = sdata; + list_add_tail(&mac_pkt->node, &sdata->local->rx_mac_cmd_list); + queue_work(sdata->local->mac_wq, &sdata->local->rx_mac_cmd_work); + return NET_RX_SUCCESS; + + case IEEE802154_FC_TYPE_ACK: + 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); + return; + } + + 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(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; + struct sk_buff *skb2; + + ret = ieee802154_parse_frame_start(skb, &hdr); + if (ret) { + pr_debug("got invalid frame\n"); + return; + } + + list_for_each_entry_rcu(sdata, &local->interfaces, list) { + if (sdata->wpan_dev.iftype == NL802154_IFTYPE_MONITOR) + continue; + + if (!ieee802154_sdata_running(sdata)) + continue; + + /* Do not deliver packets received on interfaces expecting + * AACK=1 if the address filters where disabled. + */ + if (local->hw.phy->filtering < IEEE802154_FILTERING_4_FRAME_FIELDS && + sdata->required_filtering == IEEE802154_FILTERING_4_FRAME_FIELDS) + continue; + + skb2 = skb_clone(skb, GFP_ATOMIC); + if (skb2) { + skb2->dev = sdata->dev; + ieee802154_subif_frame(sdata, skb2, &hdr); + } + } +} + +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 free_skb; + + /* 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); + + /* Level 1 filtering: Check the FCS by software when relevant */ + if (local->hw.phy->filtering == IEEE802154_FILTERING_NONE) { + crc = crc_ccitt(0, skb->data, skb->len); + if (crc) + goto drop; + } + /* remove crc */ + skb_trim(skb, skb->len - 2); + + __ieee802154_rx_handle_packet(local, skb); + +drop: + rcu_read_unlock(); +free_skb: + 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); + struct ieee802154_mac_cb *cb = mac_cb_init(skb); + + cb->lqi = lqi; + skb->pkt_type = IEEE802154_RX_MSG; + skb_queue_tail(&local->skb_queue, skb); + tasklet_schedule(&local->tasklet); +} +EXPORT_SYMBOL(ieee802154_rx_irqsafe); |