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-rw-r--r--net/mac80211/util.c486
1 files changed, 486 insertions, 0 deletions
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
new file mode 100644
index 000000000000..5a0564e1dbd6
--- /dev/null
+++ b/net/mac80211/util.c
@@ -0,0 +1,486 @@
+/*
+ * Copyright 2002-2005, Instant802 Networks, Inc.
+ * Copyright 2005-2006, Devicescape Software, Inc.
+ * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
+ * Copyright 2007 Johannes Berg <johannes@sipsolutions.net>
+ *
+ * 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.
+ *
+ * utilities for mac80211
+ */
+
+#include <net/mac80211.h>
+#include <linux/netdevice.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/skbuff.h>
+#include <linux/etherdevice.h>
+#include <linux/if_arp.h>
+#include <linux/wireless.h>
+#include <linux/bitmap.h>
+#include <net/net_namespace.h>
+#include <net/cfg80211.h>
+
+#include "ieee80211_i.h"
+#include "ieee80211_rate.h"
+#include "wme.h"
+
+/* privid for wiphys to determine whether they belong to us or not */
+void *mac80211_wiphy_privid = &mac80211_wiphy_privid;
+
+/* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
+/* Ethernet-II snap header (RFC1042 for most EtherTypes) */
+const unsigned char rfc1042_header[] =
+ { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
+
+/* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
+const unsigned char bridge_tunnel_header[] =
+ { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
+
+/* No encapsulation header if EtherType < 0x600 (=length) */
+static const unsigned char eapol_header[] =
+ { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00, 0x88, 0x8e };
+
+
+static int rate_list_match(const int *rate_list, int rate)
+{
+ int i;
+
+ if (!rate_list)
+ return 0;
+
+ for (i = 0; rate_list[i] >= 0; i++)
+ if (rate_list[i] == rate)
+ return 1;
+
+ return 0;
+}
+
+void ieee80211_prepare_rates(struct ieee80211_local *local,
+ struct ieee80211_hw_mode *mode)
+{
+ int i;
+
+ for (i = 0; i < mode->num_rates; i++) {
+ struct ieee80211_rate *rate = &mode->rates[i];
+
+ rate->flags &= ~(IEEE80211_RATE_SUPPORTED |
+ IEEE80211_RATE_BASIC);
+
+ if (local->supp_rates[mode->mode]) {
+ if (!rate_list_match(local->supp_rates[mode->mode],
+ rate->rate))
+ continue;
+ }
+
+ rate->flags |= IEEE80211_RATE_SUPPORTED;
+
+ /* Use configured basic rate set if it is available. If not,
+ * use defaults that are sane for most cases. */
+ if (local->basic_rates[mode->mode]) {
+ if (rate_list_match(local->basic_rates[mode->mode],
+ rate->rate))
+ rate->flags |= IEEE80211_RATE_BASIC;
+ } else switch (mode->mode) {
+ case MODE_IEEE80211A:
+ if (rate->rate == 60 || rate->rate == 120 ||
+ rate->rate == 240)
+ rate->flags |= IEEE80211_RATE_BASIC;
+ break;
+ case MODE_IEEE80211B:
+ if (rate->rate == 10 || rate->rate == 20)
+ rate->flags |= IEEE80211_RATE_BASIC;
+ break;
+ case MODE_IEEE80211G:
+ if (rate->rate == 10 || rate->rate == 20 ||
+ rate->rate == 55 || rate->rate == 110)
+ rate->flags |= IEEE80211_RATE_BASIC;
+ break;
+ case NUM_IEEE80211_MODES:
+ /* not useful */
+ break;
+ }
+
+ /* Set ERP and MANDATORY flags based on phymode */
+ switch (mode->mode) {
+ case MODE_IEEE80211A:
+ if (rate->rate == 60 || rate->rate == 120 ||
+ rate->rate == 240)
+ rate->flags |= IEEE80211_RATE_MANDATORY;
+ break;
+ case MODE_IEEE80211B:
+ if (rate->rate == 10)
+ rate->flags |= IEEE80211_RATE_MANDATORY;
+ break;
+ case MODE_IEEE80211G:
+ if (rate->rate == 10 || rate->rate == 20 ||
+ rate->rate == 55 || rate->rate == 110 ||
+ rate->rate == 60 || rate->rate == 120 ||
+ rate->rate == 240)
+ rate->flags |= IEEE80211_RATE_MANDATORY;
+ break;
+ case NUM_IEEE80211_MODES:
+ /* not useful */
+ break;
+ }
+ if (ieee80211_is_erp_rate(mode->mode, rate->rate))
+ rate->flags |= IEEE80211_RATE_ERP;
+ }
+}
+
+u8 *ieee80211_get_bssid(struct ieee80211_hdr *hdr, size_t len)
+{
+ u16 fc;
+
+ if (len < 24)
+ return NULL;
+
+ fc = le16_to_cpu(hdr->frame_control);
+
+ switch (fc & IEEE80211_FCTL_FTYPE) {
+ case IEEE80211_FTYPE_DATA:
+ switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
+ case IEEE80211_FCTL_TODS:
+ return hdr->addr1;
+ case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
+ return NULL;
+ case IEEE80211_FCTL_FROMDS:
+ return hdr->addr2;
+ case 0:
+ return hdr->addr3;
+ }
+ break;
+ case IEEE80211_FTYPE_MGMT:
+ return hdr->addr3;
+ case IEEE80211_FTYPE_CTL:
+ if ((fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL)
+ return hdr->addr1;
+ else
+ return NULL;
+ }
+
+ return NULL;
+}
+
+int ieee80211_get_hdrlen(u16 fc)
+{
+ int hdrlen = 24;
+
+ switch (fc & IEEE80211_FCTL_FTYPE) {
+ case IEEE80211_FTYPE_DATA:
+ if ((fc & IEEE80211_FCTL_FROMDS) && (fc & IEEE80211_FCTL_TODS))
+ hdrlen = 30; /* Addr4 */
+ /*
+ * The QoS Control field is two bytes and its presence is
+ * indicated by the IEEE80211_STYPE_QOS_DATA bit. Add 2 to
+ * hdrlen if that bit is set.
+ * This works by masking out the bit and shifting it to
+ * bit position 1 so the result has the value 0 or 2.
+ */
+ hdrlen += (fc & IEEE80211_STYPE_QOS_DATA)
+ >> (ilog2(IEEE80211_STYPE_QOS_DATA)-1);
+ break;
+ case IEEE80211_FTYPE_CTL:
+ /*
+ * ACK and CTS are 10 bytes, all others 16. To see how
+ * to get this condition consider
+ * subtype mask: 0b0000000011110000 (0x00F0)
+ * ACK subtype: 0b0000000011010000 (0x00D0)
+ * CTS subtype: 0b0000000011000000 (0x00C0)
+ * bits that matter: ^^^ (0x00E0)
+ * value of those: 0b0000000011000000 (0x00C0)
+ */
+ if ((fc & 0xE0) == 0xC0)
+ hdrlen = 10;
+ else
+ hdrlen = 16;
+ break;
+ }
+
+ return hdrlen;
+}
+EXPORT_SYMBOL(ieee80211_get_hdrlen);
+
+int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
+{
+ const struct ieee80211_hdr *hdr = (const struct ieee80211_hdr *) skb->data;
+ int hdrlen;
+
+ if (unlikely(skb->len < 10))
+ return 0;
+ hdrlen = ieee80211_get_hdrlen(le16_to_cpu(hdr->frame_control));
+ if (unlikely(hdrlen > skb->len))
+ return 0;
+ return hdrlen;
+}
+EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);
+
+int ieee80211_is_eapol(const struct sk_buff *skb)
+{
+ const struct ieee80211_hdr *hdr;
+ u16 fc;
+ int hdrlen;
+
+ if (unlikely(skb->len < 10))
+ return 0;
+
+ hdr = (const struct ieee80211_hdr *) skb->data;
+ fc = le16_to_cpu(hdr->frame_control);
+
+ if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
+ return 0;
+
+ hdrlen = ieee80211_get_hdrlen(fc);
+
+ if (unlikely(skb->len >= hdrlen + sizeof(eapol_header) &&
+ memcmp(skb->data + hdrlen, eapol_header,
+ sizeof(eapol_header)) == 0))
+ return 1;
+
+ return 0;
+}
+
+void ieee80211_tx_set_iswep(struct ieee80211_txrx_data *tx)
+{
+ struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
+
+ hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
+ if (tx->u.tx.extra_frag) {
+ struct ieee80211_hdr *fhdr;
+ int i;
+ for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
+ fhdr = (struct ieee80211_hdr *)
+ tx->u.tx.extra_frag[i]->data;
+ fhdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
+ }
+ }
+}
+
+int ieee80211_frame_duration(struct ieee80211_local *local, size_t len,
+ int rate, int erp, int short_preamble)
+{
+ int dur;
+
+ /* calculate duration (in microseconds, rounded up to next higher
+ * integer if it includes a fractional microsecond) to send frame of
+ * len bytes (does not include FCS) at the given rate. Duration will
+ * also include SIFS.
+ *
+ * rate is in 100 kbps, so divident is multiplied by 10 in the
+ * DIV_ROUND_UP() operations.
+ */
+
+ if (local->hw.conf.phymode == MODE_IEEE80211A || erp) {
+ /*
+ * OFDM:
+ *
+ * N_DBPS = DATARATE x 4
+ * N_SYM = Ceiling((16+8xLENGTH+6) / N_DBPS)
+ * (16 = SIGNAL time, 6 = tail bits)
+ * TXTIME = T_PREAMBLE + T_SIGNAL + T_SYM x N_SYM + Signal Ext
+ *
+ * T_SYM = 4 usec
+ * 802.11a - 17.5.2: aSIFSTime = 16 usec
+ * 802.11g - 19.8.4: aSIFSTime = 10 usec +
+ * signal ext = 6 usec
+ */
+ dur = 16; /* SIFS + signal ext */
+ dur += 16; /* 17.3.2.3: T_PREAMBLE = 16 usec */
+ dur += 4; /* 17.3.2.3: T_SIGNAL = 4 usec */
+ dur += 4 * DIV_ROUND_UP((16 + 8 * (len + 4) + 6) * 10,
+ 4 * rate); /* T_SYM x N_SYM */
+ } else {
+ /*
+ * 802.11b or 802.11g with 802.11b compatibility:
+ * 18.3.4: TXTIME = PreambleLength + PLCPHeaderTime +
+ * Ceiling(((LENGTH+PBCC)x8)/DATARATE). PBCC=0.
+ *
+ * 802.11 (DS): 15.3.3, 802.11b: 18.3.4
+ * aSIFSTime = 10 usec
+ * aPreambleLength = 144 usec or 72 usec with short preamble
+ * aPLCPHeaderLength = 48 usec or 24 usec with short preamble
+ */
+ dur = 10; /* aSIFSTime = 10 usec */
+ dur += short_preamble ? (72 + 24) : (144 + 48);
+
+ dur += DIV_ROUND_UP(8 * (len + 4) * 10, rate);
+ }
+
+ return dur;
+}
+
+/* Exported duration function for driver use */
+__le16 ieee80211_generic_frame_duration(struct ieee80211_hw *hw, int if_id,
+ size_t frame_len, int rate)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+ struct net_device *bdev = dev_get_by_index(&init_net, if_id);
+ struct ieee80211_sub_if_data *sdata;
+ u16 dur;
+ int erp;
+
+ if (unlikely(!bdev))
+ return 0;
+
+ sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
+ erp = ieee80211_is_erp_rate(hw->conf.phymode, rate);
+ dur = ieee80211_frame_duration(local, frame_len, rate,
+ erp, sdata->flags & IEEE80211_SDATA_SHORT_PREAMBLE);
+
+ dev_put(bdev);
+ return cpu_to_le16(dur);
+}
+EXPORT_SYMBOL(ieee80211_generic_frame_duration);
+
+__le16 ieee80211_rts_duration(struct ieee80211_hw *hw, int if_id,
+ size_t frame_len,
+ const struct ieee80211_tx_control *frame_txctl)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+ struct ieee80211_rate *rate;
+ struct net_device *bdev = dev_get_by_index(&init_net, if_id);
+ struct ieee80211_sub_if_data *sdata;
+ int short_preamble;
+ int erp;
+ u16 dur;
+
+ if (unlikely(!bdev))
+ return 0;
+
+ sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
+ short_preamble = sdata->flags & IEEE80211_SDATA_SHORT_PREAMBLE;
+
+ rate = frame_txctl->rts_rate;
+ erp = !!(rate->flags & IEEE80211_RATE_ERP);
+
+ /* CTS duration */
+ dur = ieee80211_frame_duration(local, 10, rate->rate,
+ erp, short_preamble);
+ /* Data frame duration */
+ dur += ieee80211_frame_duration(local, frame_len, rate->rate,
+ erp, short_preamble);
+ /* ACK duration */
+ dur += ieee80211_frame_duration(local, 10, rate->rate,
+ erp, short_preamble);
+
+ dev_put(bdev);
+ return cpu_to_le16(dur);
+}
+EXPORT_SYMBOL(ieee80211_rts_duration);
+
+__le16 ieee80211_ctstoself_duration(struct ieee80211_hw *hw, int if_id,
+ size_t frame_len,
+ const struct ieee80211_tx_control *frame_txctl)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+ struct ieee80211_rate *rate;
+ struct net_device *bdev = dev_get_by_index(&init_net, if_id);
+ struct ieee80211_sub_if_data *sdata;
+ int short_preamble;
+ int erp;
+ u16 dur;
+
+ if (unlikely(!bdev))
+ return 0;
+
+ sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
+ short_preamble = sdata->flags & IEEE80211_SDATA_SHORT_PREAMBLE;
+
+ rate = frame_txctl->rts_rate;
+ erp = !!(rate->flags & IEEE80211_RATE_ERP);
+
+ /* Data frame duration */
+ dur = ieee80211_frame_duration(local, frame_len, rate->rate,
+ erp, short_preamble);
+ if (!(frame_txctl->flags & IEEE80211_TXCTL_NO_ACK)) {
+ /* ACK duration */
+ dur += ieee80211_frame_duration(local, 10, rate->rate,
+ erp, short_preamble);
+ }
+
+ dev_put(bdev);
+ return cpu_to_le16(dur);
+}
+EXPORT_SYMBOL(ieee80211_ctstoself_duration);
+
+struct ieee80211_rate *
+ieee80211_get_rate(struct ieee80211_local *local, int phymode, int hw_rate)
+{
+ struct ieee80211_hw_mode *mode;
+ int r;
+
+ list_for_each_entry(mode, &local->modes_list, list) {
+ if (mode->mode != phymode)
+ continue;
+ for (r = 0; r < mode->num_rates; r++) {
+ struct ieee80211_rate *rate = &mode->rates[r];
+ if (rate->val == hw_rate ||
+ (rate->flags & IEEE80211_RATE_PREAMBLE2 &&
+ rate->val2 == hw_rate))
+ return rate;
+ }
+ }
+
+ return NULL;
+}
+
+void ieee80211_wake_queue(struct ieee80211_hw *hw, int queue)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+
+ if (test_and_clear_bit(IEEE80211_LINK_STATE_XOFF,
+ &local->state[queue])) {
+ if (test_bit(IEEE80211_LINK_STATE_PENDING,
+ &local->state[queue]))
+ tasklet_schedule(&local->tx_pending_tasklet);
+ else
+ if (!ieee80211_qdisc_installed(local->mdev)) {
+ if (queue == 0)
+ netif_wake_queue(local->mdev);
+ } else
+ __netif_schedule(local->mdev);
+ }
+}
+EXPORT_SYMBOL(ieee80211_wake_queue);
+
+void ieee80211_stop_queue(struct ieee80211_hw *hw, int queue)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+
+ if (!ieee80211_qdisc_installed(local->mdev) && queue == 0)
+ netif_stop_queue(local->mdev);
+ set_bit(IEEE80211_LINK_STATE_XOFF, &local->state[queue]);
+}
+EXPORT_SYMBOL(ieee80211_stop_queue);
+
+void ieee80211_start_queues(struct ieee80211_hw *hw)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+ int i;
+
+ for (i = 0; i < local->hw.queues; i++)
+ clear_bit(IEEE80211_LINK_STATE_XOFF, &local->state[i]);
+ if (!ieee80211_qdisc_installed(local->mdev))
+ netif_start_queue(local->mdev);
+}
+EXPORT_SYMBOL(ieee80211_start_queues);
+
+void ieee80211_stop_queues(struct ieee80211_hw *hw)
+{
+ int i;
+
+ for (i = 0; i < hw->queues; i++)
+ ieee80211_stop_queue(hw, i);
+}
+EXPORT_SYMBOL(ieee80211_stop_queues);
+
+void ieee80211_wake_queues(struct ieee80211_hw *hw)
+{
+ int i;
+
+ for (i = 0; i < hw->queues; i++)
+ ieee80211_wake_queue(hw, i);
+}
+EXPORT_SYMBOL(ieee80211_wake_queues);
generated by cgit v1.2.3 (git 2.0.4) at 2024-11-05 15:17:57 +0000