diff options
Diffstat (limited to 'gpxe/src/net/80211/net80211.c')
| -rw-r--r-- | gpxe/src/net/80211/net80211.c | 2829 |
1 files changed, 0 insertions, 2829 deletions
diff --git a/gpxe/src/net/80211/net80211.c b/gpxe/src/net/80211/net80211.c deleted file mode 100644 index 1c54597f..00000000 --- a/gpxe/src/net/80211/net80211.c +++ /dev/null @@ -1,2829 +0,0 @@ -/* - * The gPXE 802.11 MAC layer. - * - * Copyright (c) 2009 Joshua Oreman <oremanj@rwcr.net>. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License as - * published by the Free Software Foundation; either version 2 of the - * License, or any later version. - * - * 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. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - */ - -FILE_LICENCE ( GPL2_OR_LATER ); - -#include <string.h> -#include <byteswap.h> -#include <stdlib.h> -#include <gpxe/settings.h> -#include <gpxe/if_arp.h> -#include <gpxe/ethernet.h> -#include <gpxe/ieee80211.h> -#include <gpxe/netdevice.h> -#include <gpxe/net80211.h> -#include <gpxe/sec80211.h> -#include <gpxe/timer.h> -#include <gpxe/nap.h> -#include <unistd.h> -#include <errno.h> - -/** @file - * - * 802.11 device management - */ - -/* Disambiguate the EINVAL's a bit */ -#define EINVAL_PKT_TOO_SHORT ( EINVAL | EUNIQ_01 ) -#define EINVAL_PKT_VERSION ( EINVAL | EUNIQ_02 ) -#define EINVAL_PKT_NOT_DATA ( EINVAL | EUNIQ_03 ) -#define EINVAL_PKT_NOT_FROMDS ( EINVAL | EUNIQ_04 ) -#define EINVAL_PKT_LLC_HEADER ( EINVAL | EUNIQ_05 ) -#define EINVAL_CRYPTO_REQUEST ( EINVAL | EUNIQ_06 ) -#define EINVAL_ACTIVE_SCAN ( EINVAL | EUNIQ_07 ) - -/* - * 802.11 error codes: The AP can give us a status code explaining why - * authentication failed, or a reason code explaining why we were - * deauthenticated/disassociated. These codes range from 0-63 (the - * field is 16 bits wide, but only up to 45 or so are defined yet; we - * allow up to 63 for extensibility). This is encoded into an error - * code as such: - * - * status & 0x1f goes here --vv-- - * Status code 0-31: ECONNREFUSED | EUNIQ_(status & 0x1f) (0e1a6038) - * Status code 32-63: EHOSTUNREACH | EUNIQ_(status & 0x1f) (171a6011) - * Reason code 0-31: ECONNRESET | EUNIQ_(reason & 0x1f) (0f1a6039) - * Reason code 32-63: ENETRESET | EUNIQ_(reason & 0x1f) (271a6001) - * - * The POSIX error codes more or less convey the appropriate message - * (status codes occur when we can't associate at all, reason codes - * when we lose association unexpectedly) and let us extract the - * complete 802.11 error code from the rc value. - */ - -/** Make return status code from 802.11 status code */ -#define E80211_STATUS( stat ) ( ((stat & 0x20)? EHOSTUNREACH : ECONNREFUSED) \ - | ((stat & 0x1f) << 8) ) - -/** Make return status code from 802.11 reason code */ -#define E80211_REASON( reas ) ( ((reas & 0x20)? ENETRESET : ECONNRESET) \ - | ((reas & 0x1f) << 8) ) - - -/** List of 802.11 devices */ -static struct list_head net80211_devices = LIST_HEAD_INIT ( net80211_devices ); - -/** Set of device operations that does nothing */ -static struct net80211_device_operations net80211_null_ops; - -/** Information associated with a received management packet - * - * This is used to keep beacon signal strengths in a parallel queue to - * the beacons themselves. - */ -struct net80211_rx_info { - int signal; - struct list_head list; -}; - -/** Context for a probe operation */ -struct net80211_probe_ctx { - /** 802.11 device to probe on */ - struct net80211_device *dev; - - /** Value of keep_mgmt before probe was started */ - int old_keep_mgmt; - - /** If scanning actively, pointer to probe packet to send */ - struct io_buffer *probe; - - /** If non-"", the ESSID to limit ourselves to */ - const char *essid; - - /** Time probe was started */ - u32 ticks_start; - - /** Time last useful beacon was received */ - u32 ticks_beacon; - - /** Time channel was last changed */ - u32 ticks_channel; - - /** Time to stay on each channel */ - u32 hop_time; - - /** Channels to hop by when changing channel */ - int hop_step; - - /** List of best beacons for each network found so far */ - struct list_head *beacons; -}; - -/** Context for the association task */ -struct net80211_assoc_ctx { - /** Next authentication method to try using */ - int method; - - /** Time (in ticks) of the last sent association-related packet */ - int last_packet; - - /** Number of times we have tried sending it */ - int times_tried; -}; - -/** - * @defgroup net80211_netdev Network device interface functions - * @{ - */ -static int net80211_netdev_open ( struct net_device *netdev ); -static void net80211_netdev_close ( struct net_device *netdev ); -static int net80211_netdev_transmit ( struct net_device *netdev, - struct io_buffer *iobuf ); -static void net80211_netdev_poll ( struct net_device *netdev ); -static void net80211_netdev_irq ( struct net_device *netdev, int enable ); -/** @} */ - -/** - * @defgroup net80211_linklayer 802.11 link-layer protocol functions - * @{ - */ -static int net80211_ll_push ( struct net_device *netdev, - struct io_buffer *iobuf, const void *ll_dest, - const void *ll_source, uint16_t net_proto ); -static int net80211_ll_pull ( struct net_device *netdev, - struct io_buffer *iobuf, const void **ll_dest, - const void **ll_source, uint16_t * net_proto ); -/** @} */ - -/** - * @defgroup net80211_help 802.11 helper functions - * @{ - */ -static void net80211_add_channels ( struct net80211_device *dev, int start, - int len, int txpower ); -static void net80211_filter_hw_channels ( struct net80211_device *dev ); -static void net80211_set_rtscts_rate ( struct net80211_device *dev ); -static int net80211_process_capab ( struct net80211_device *dev, - u16 capab ); -static int net80211_process_ie ( struct net80211_device *dev, - union ieee80211_ie *ie, void *ie_end ); -static union ieee80211_ie * -net80211_marshal_request_info ( struct net80211_device *dev, - union ieee80211_ie *ie ); -/** @} */ - -/** - * @defgroup net80211_assoc_ll 802.11 association handling functions - * @{ - */ -static void net80211_step_associate ( struct process *proc ); -static void net80211_handle_auth ( struct net80211_device *dev, - struct io_buffer *iob ); -static void net80211_handle_assoc_reply ( struct net80211_device *dev, - struct io_buffer *iob ); -static int net80211_send_disassoc ( struct net80211_device *dev, int reason, - int deauth ); -static void net80211_handle_mgmt ( struct net80211_device *dev, - struct io_buffer *iob, int signal ); -/** @} */ - -/** - * @defgroup net80211_frag 802.11 fragment handling functions - * @{ - */ -static void net80211_free_frags ( struct net80211_device *dev, int fcid ); -static struct io_buffer *net80211_accum_frags ( struct net80211_device *dev, - int fcid, int nfrags, int size ); -static void net80211_rx_frag ( struct net80211_device *dev, - struct io_buffer *iob, int signal ); -/** @} */ - -/** - * @defgroup net80211_settings 802.11 settings handlers - * @{ - */ -static int net80211_check_settings_update ( void ); - -/** 802.11 settings applicator - * - * When the SSID is changed, this will cause any open devices to - * re-associate; when the encryption key is changed, we similarly - * update their state. - */ -struct settings_applicator net80211_applicator __settings_applicator = { - .apply = net80211_check_settings_update, -}; - -/** The network name to associate with - * - * If this is blank, we scan for all networks and use the one with the - * greatest signal strength. - */ -struct setting net80211_ssid_setting __setting = { - .name = "ssid", - .description = "802.11 SSID (network name)", - .type = &setting_type_string, -}; - -/** Whether to use active scanning - * - * In order to associate with a hidden SSID, it's necessary to use an - * active scan (send probe packets). If this setting is nonzero, an - * active scan on the 2.4GHz band will be used to associate. - */ -struct setting net80211_active_setting __setting = { - .name = "active-scan", - .description = "Use an active scan during 802.11 association", - .type = &setting_type_int8, -}; - -/** The cryptographic key to use - * - * For hex WEP keys, as is common, this must be entered using the - * normal gPXE method for entering hex settings; an ASCII string of - * hex characters will not behave as expected. - */ -struct setting net80211_key_setting __setting = { - .name = "key", - .description = "Encryption key for protected 802.11 networks", - .type = &setting_type_string, -}; - -/** @} */ - - -/* ---------- net_device wrapper ---------- */ - -/** - * Open 802.11 device and start association - * - * @v netdev Wrapping network device - * @ret rc Return status code - * - * This sets up a default conservative set of channels for probing, - * and starts the auto-association task unless the @c - * NET80211_NO_ASSOC flag is set in the wrapped 802.11 device's @c - * state field. - */ -static int net80211_netdev_open ( struct net_device *netdev ) -{ - struct net80211_device *dev = netdev->priv; - int rc = 0; - - if ( dev->op == &net80211_null_ops ) - return -EFAULT; - - if ( dev->op->open ) - rc = dev->op->open ( dev ); - - if ( rc < 0 ) - return rc; - - if ( ! ( dev->state & NET80211_NO_ASSOC ) ) - net80211_autoassociate ( dev ); - - return 0; -} - -/** - * Close 802.11 device - * - * @v netdev Wrapping network device. - * - * If the association task is running, this will stop it. - */ -static void net80211_netdev_close ( struct net_device *netdev ) -{ - struct net80211_device *dev = netdev->priv; - - if ( dev->state & NET80211_WORKING ) - process_del ( &dev->proc_assoc ); - - /* Send disassociation frame to AP, to be polite */ - if ( dev->state & NET80211_ASSOCIATED ) - net80211_send_disassoc ( dev, IEEE80211_REASON_LEAVING, 0 ); - - if ( dev->handshaker && dev->handshaker->stop && - dev->handshaker->started ) - dev->handshaker->stop ( dev ); - - free ( dev->crypto ); - free ( dev->handshaker ); - dev->crypto = NULL; - dev->handshaker = NULL; - - netdev_link_down ( netdev ); - dev->state = 0; - - if ( dev->op->close ) - dev->op->close ( dev ); -} - -/** - * Transmit packet on 802.11 device - * - * @v netdev Wrapping network device - * @v iobuf I/O buffer - * @ret rc Return status code - * - * If encryption is enabled for the currently associated network, the - * packet will be encrypted prior to transmission. - */ -static int net80211_netdev_transmit ( struct net_device *netdev, - struct io_buffer *iobuf ) -{ - struct net80211_device *dev = netdev->priv; - struct ieee80211_frame *hdr = iobuf->data; - int rc = -ENOSYS; - - if ( dev->crypto && ! ( hdr->fc & IEEE80211_FC_PROTECTED ) && - ( ( hdr->fc & IEEE80211_FC_TYPE ) == IEEE80211_TYPE_DATA ) ) { - struct io_buffer *niob = dev->crypto->encrypt ( dev->crypto, - iobuf ); - if ( ! niob ) - return -ENOMEM; /* only reason encryption could fail */ - - /* Free the non-encrypted iob */ - netdev_tx_complete ( netdev, iobuf ); - - /* Transmit the encrypted iob; the Protected flag is - set, so we won't recurse into here again */ - netdev_tx ( netdev, niob ); - - /* Don't transmit the freed packet */ - return 0; - } - - if ( dev->op->transmit ) - rc = dev->op->transmit ( dev, iobuf ); - - return rc; -} - -/** - * Poll 802.11 device for received packets and completed transmissions - * - * @v netdev Wrapping network device - */ -static void net80211_netdev_poll ( struct net_device *netdev ) -{ - struct net80211_device *dev = netdev->priv; - - if ( dev->op->poll ) - dev->op->poll ( dev ); -} - -/** - * Enable or disable interrupts for 802.11 device - * - * @v netdev Wrapping network device - * @v enable Whether to enable interrupts - */ -static void net80211_netdev_irq ( struct net_device *netdev, int enable ) -{ - struct net80211_device *dev = netdev->priv; - - if ( dev->op->irq ) - dev->op->irq ( dev, enable ); -} - -/** Network device operations for a wrapped 802.11 device */ -static struct net_device_operations net80211_netdev_ops = { - .open = net80211_netdev_open, - .close = net80211_netdev_close, - .transmit = net80211_netdev_transmit, - .poll = net80211_netdev_poll, - .irq = net80211_netdev_irq, -}; - - -/* ---------- 802.11 link-layer protocol ---------- */ - -/** 802.11 broadcast MAC address */ -static u8 net80211_ll_broadcast[] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; - -/** - * Determine whether a transmission rate uses ERP/OFDM - * - * @v rate Rate in 100 kbps units - * @ret is_erp TRUE if the rate is an ERP/OFDM rate - * - * 802.11b supports rates of 1.0, 2.0, 5.5, and 11.0 Mbps; any other - * rate than these on the 2.4GHz spectrum is an ERP (802.11g) rate. - */ -static inline int net80211_rate_is_erp ( u16 rate ) -{ - if ( rate == 10 || rate == 20 || rate == 55 || rate == 110 ) - return 0; - return 1; -} - - -/** - * Calculate one frame's contribution to 802.11 duration field - * - * @v dev 802.11 device - * @v bytes Amount of data to calculate duration for - * @ret dur Duration field in microseconds - * - * To avoid multiple stations attempting to transmit at once, 802.11 - * provides that every packet shall include a duration field - * specifying a length of time for which the wireless medium will be - * reserved after it is transmitted. The duration is measured in - * microseconds and is calculated with respect to the current - * physical-layer parameters of the 802.11 device. - * - * For an unfragmented data or management frame, or the last fragment - * of a fragmented frame, the duration captures only the 10 data bytes - * of one ACK; call once with bytes = 10. - * - * For a fragment of a data or management rame that will be followed - * by more fragments, the duration captures an ACK, the following - * fragment, and its ACK; add the results of three calls, two with - * bytes = 10 and one with bytes set to the next fragment's size. - * - * For an RTS control frame, the duration captures the responding CTS, - * the frame being sent, and its ACK; add the results of three calls, - * two with bytes = 10 and one with bytes set to the next frame's size - * (assuming unfragmented). - * - * For a CTS-to-self control frame, the duration captures the frame - * being protected and its ACK; add the results of two calls, one with - * bytes = 10 and one with bytes set to the next frame's size. - * - * No other frame types are currently supported by gPXE. - */ -u16 net80211_duration ( struct net80211_device *dev, int bytes, u16 rate ) -{ - struct net80211_channel *chan = &dev->channels[dev->channel]; - u32 kbps = rate * 100; - - if ( chan->band == NET80211_BAND_5GHZ || net80211_rate_is_erp ( rate ) ) { - /* OFDM encoding (802.11a/g) */ - int bits_per_symbol = ( kbps * 4 ) / 1000; /* 4us/symbol */ - int bits = 22 + ( bytes << 3 ); /* 22-bit PLCP */ - int symbols = ( bits + bits_per_symbol - 1 ) / bits_per_symbol; - - return 16 + 20 + ( symbols * 4 ); /* 16us SIFS, 20us preamble */ - } else { - /* CCK encoding (802.11b) */ - int phy_time = 144 + 48; /* preamble + PLCP */ - int bits = bytes << 3; - int data_time = ( bits * 1000 + kbps - 1 ) / kbps; - - if ( dev->phy_flags & NET80211_PHY_USE_SHORT_PREAMBLE ) - phy_time >>= 1; - - return 10 + phy_time + data_time; /* 10us SIFS */ - } -} - -/** - * Add 802.11 link-layer header - * - * @v netdev Wrapping network device - * @v iobuf I/O buffer - * @v ll_dest Link-layer destination address - * @v ll_source Link-layer source address - * @v net_proto Network-layer protocol, in network byte order - * @ret rc Return status code - * - * This adds both the 802.11 frame header and the 802.2 LLC/SNAP - * header used on data packets. - * - * We also check here for state of the link that would make it invalid - * to send a data packet; every data packet must pass through here, - * and no non-data packet (e.g. management frame) should. - */ -static int net80211_ll_push ( struct net_device *netdev, - struct io_buffer *iobuf, const void *ll_dest, - const void *ll_source, uint16_t net_proto ) -{ - struct net80211_device *dev = netdev->priv; - struct ieee80211_frame *hdr = iob_push ( iobuf, - IEEE80211_LLC_HEADER_LEN + - IEEE80211_TYP_FRAME_HEADER_LEN ); - struct ieee80211_llc_snap_header *lhdr = - ( void * ) hdr + IEEE80211_TYP_FRAME_HEADER_LEN; - - /* We can't send data packets if we're not associated. */ - if ( ! ( dev->state & NET80211_ASSOCIATED ) ) { - if ( dev->assoc_rc ) - return dev->assoc_rc; - return -ENETUNREACH; - } - - hdr->fc = IEEE80211_THIS_VERSION | IEEE80211_TYPE_DATA | - IEEE80211_STYPE_DATA | IEEE80211_FC_TODS; - - /* We don't send fragmented frames, so duration is the time - for an SIFS + 10-byte ACK. */ - hdr->duration = net80211_duration ( dev, 10, dev->rates[dev->rate] ); - - memcpy ( hdr->addr1, dev->bssid, ETH_ALEN ); - memcpy ( hdr->addr2, ll_source, ETH_ALEN ); - memcpy ( hdr->addr3, ll_dest, ETH_ALEN ); - - hdr->seq = IEEE80211_MAKESEQ ( ++dev->last_tx_seqnr, 0 ); - - lhdr->dsap = IEEE80211_LLC_DSAP; - lhdr->ssap = IEEE80211_LLC_SSAP; - lhdr->ctrl = IEEE80211_LLC_CTRL; - memset ( lhdr->oui, 0x00, 3 ); - lhdr->ethertype = net_proto; - - return 0; -} - -/** - * Remove 802.11 link-layer header - * - * @v netdev Wrapping network device - * @v iobuf I/O buffer - * @ret ll_dest Link-layer destination address - * @ret ll_source Link-layer source - * @ret net_proto Network-layer protocol, in network byte order - * @ret rc Return status code - * - * This expects and removes both the 802.11 frame header and the 802.2 - * LLC/SNAP header that are used on data packets. - */ -static int net80211_ll_pull ( struct net_device *netdev __unused, - struct io_buffer *iobuf, - const void **ll_dest, const void **ll_source, - uint16_t * net_proto ) -{ - struct ieee80211_frame *hdr = iobuf->data; - struct ieee80211_llc_snap_header *lhdr = - ( void * ) hdr + IEEE80211_TYP_FRAME_HEADER_LEN; - - /* Bunch of sanity checks */ - if ( iob_len ( iobuf ) < IEEE80211_TYP_FRAME_HEADER_LEN + - IEEE80211_LLC_HEADER_LEN ) { - DBGC ( netdev->priv, "802.11 %p packet too short (%zd bytes)\n", - netdev->priv, iob_len ( iobuf ) ); - return -EINVAL_PKT_TOO_SHORT; - } - - if ( ( hdr->fc & IEEE80211_FC_VERSION ) != IEEE80211_THIS_VERSION ) { - DBGC ( netdev->priv, "802.11 %p packet invalid version %04x\n", - netdev->priv, hdr->fc & IEEE80211_FC_VERSION ); - return -EINVAL_PKT_VERSION; - } - - if ( ( hdr->fc & IEEE80211_FC_TYPE ) != IEEE80211_TYPE_DATA || - ( hdr->fc & IEEE80211_FC_SUBTYPE ) != IEEE80211_STYPE_DATA ) { - DBGC ( netdev->priv, "802.11 %p packet not data/data (fc=%04x)\n", - netdev->priv, hdr->fc ); - return -EINVAL_PKT_NOT_DATA; - } - - if ( ( hdr->fc & ( IEEE80211_FC_TODS | IEEE80211_FC_FROMDS ) ) != - IEEE80211_FC_FROMDS ) { - DBGC ( netdev->priv, "802.11 %p packet not from DS (fc=%04x)\n", - netdev->priv, hdr->fc ); - return -EINVAL_PKT_NOT_FROMDS; - } - - if ( lhdr->dsap != IEEE80211_LLC_DSAP || lhdr->ssap != IEEE80211_LLC_SSAP || - lhdr->ctrl != IEEE80211_LLC_CTRL || lhdr->oui[0] || lhdr->oui[1] || - lhdr->oui[2] ) { - DBGC ( netdev->priv, "802.11 %p LLC header is not plain EtherType " - "encapsulator: %02x->%02x [%02x] %02x:%02x:%02x %04x\n", - netdev->priv, lhdr->dsap, lhdr->ssap, lhdr->ctrl, - lhdr->oui[0], lhdr->oui[1], lhdr->oui[2], lhdr->ethertype ); - return -EINVAL_PKT_LLC_HEADER; - } - - iob_pull ( iobuf, sizeof ( *hdr ) + sizeof ( *lhdr ) ); - - *ll_dest = hdr->addr1; - *ll_source = hdr->addr3; - *net_proto = lhdr->ethertype; - return 0; -} - -/** 802.11 link-layer protocol */ -static struct ll_protocol net80211_ll_protocol __ll_protocol = { - .name = "802.11", - .push = net80211_ll_push, - .pull = net80211_ll_pull, - .init_addr = eth_init_addr, - .ntoa = eth_ntoa, - .mc_hash = eth_mc_hash, - .eth_addr = eth_eth_addr, - .ll_proto = htons ( ARPHRD_ETHER ), /* "encapsulated Ethernet" */ - .hw_addr_len = ETH_ALEN, - .ll_addr_len = ETH_ALEN, - .ll_header_len = IEEE80211_TYP_FRAME_HEADER_LEN + - IEEE80211_LLC_HEADER_LEN, -}; - - -/* ---------- 802.11 network management API ---------- */ - -/** - * Get 802.11 device from wrapping network device - * - * @v netdev Wrapping network device - * @ret dev 802.11 device wrapped by network device, or NULL - * - * Returns NULL if the network device does not wrap an 802.11 device. - */ -struct net80211_device * net80211_get ( struct net_device *netdev ) -{ - struct net80211_device *dev; - - list_for_each_entry ( dev, &net80211_devices, list ) { - if ( netdev->priv == dev ) - return netdev->priv; - } - - return NULL; -} - -/** - * Set state of 802.11 device keeping management frames - * - * @v dev 802.11 device - * @v enable Whether to keep management frames - * @ret oldenab Whether management frames were enabled before this call - * - * If enable is TRUE, beacon, probe, and action frames will be kept - * and may be retrieved by calling net80211_mgmt_dequeue(). - */ -int net80211_keep_mgmt ( struct net80211_device *dev, int enable ) -{ - int oldenab = dev->keep_mgmt; - - dev->keep_mgmt = enable; - return oldenab; -} - -/** - * Get 802.11 management frame - * - * @v dev 802.11 device - * @ret signal Signal strength of returned management frame - * @ret iob I/O buffer, or NULL if no management frame is queued - * - * Frames will only be returned by this function if - * net80211_keep_mgmt() has been previously called with enable set to - * TRUE. - * - * The calling function takes ownership of the returned I/O buffer. - */ -struct io_buffer * net80211_mgmt_dequeue ( struct net80211_device *dev, - int *signal ) -{ - struct io_buffer *iobuf; - struct net80211_rx_info *rxi; - - list_for_each_entry ( rxi, &dev->mgmt_info_queue, list ) { - list_del ( &rxi->list ); - if ( signal ) - *signal = rxi->signal; - free ( rxi ); - - list_for_each_entry ( iobuf, &dev->mgmt_queue, list ) { - list_del ( &iobuf->list ); - return iobuf; - } - assert ( 0 ); - } - - return NULL; -} - -/** - * Transmit 802.11 management frame - * - * @v dev 802.11 device - * @v fc Frame Control flags for management frame - * @v dest Destination access point - * @v iob I/O buffer - * @ret rc Return status code - * - * The @a fc argument must contain at least an IEEE 802.11 management - * subtype number (e.g. IEEE80211_STYPE_PROBE_REQ). If it contains - * IEEE80211_FC_PROTECTED, the frame will be encrypted prior to - * transmission. - * - * It is required that @a iob have at least 24 bytes of headroom - * reserved before its data start. - */ -int net80211_tx_mgmt ( struct net80211_device *dev, u16 fc, u8 dest[6], - struct io_buffer *iob ) -{ - struct ieee80211_frame *hdr = iob_push ( iob, - IEEE80211_TYP_FRAME_HEADER_LEN ); - - hdr->fc = IEEE80211_THIS_VERSION | IEEE80211_TYPE_MGMT | - ( fc & ~IEEE80211_FC_PROTECTED ); - hdr->duration = net80211_duration ( dev, 10, dev->rates[dev->rate] ); - hdr->seq = IEEE80211_MAKESEQ ( ++dev->last_tx_seqnr, 0 ); - - memcpy ( hdr->addr1, dest, ETH_ALEN ); /* DA = RA */ - memcpy ( hdr->addr2, dev->netdev->ll_addr, ETH_ALEN ); /* SA = TA */ - memcpy ( hdr->addr3, dest, ETH_ALEN ); /* BSSID */ - - if ( fc & IEEE80211_FC_PROTECTED ) { - if ( ! dev->crypto ) - return -EINVAL_CRYPTO_REQUEST; - - struct io_buffer *eiob = dev->crypto->encrypt ( dev->crypto, - iob ); - free_iob ( iob ); - iob = eiob; - } - - return netdev_tx ( dev->netdev, iob ); -} - - -/* ---------- Driver API ---------- */ - -/** - * Allocate 802.11 device - * - * @v priv_size Size of driver-private allocation area - * @ret dev Newly allocated 802.11 device - * - * This function allocates a net_device with space in its private area - * for both the net80211_device it will wrap and the driver-private - * data space requested. It initializes the link-layer-specific parts - * of the net_device, and links the net80211_device to the net_device - * appropriately. - */ -struct net80211_device * net80211_alloc ( size_t priv_size ) -{ - struct net80211_device *dev; - struct net_device *netdev = - alloc_netdev ( sizeof ( *dev ) + priv_size ); - - if ( ! netdev ) - return NULL; - - netdev->ll_protocol = &net80211_ll_protocol; - netdev->ll_broadcast = net80211_ll_broadcast; - netdev->max_pkt_len = IEEE80211_MAX_DATA_LEN; - netdev_init ( netdev, &net80211_netdev_ops ); - - dev = netdev->priv; - dev->netdev = netdev; - dev->priv = ( u8 * ) dev + sizeof ( *dev ); - dev->op = &net80211_null_ops; - - process_init_stopped ( &dev->proc_assoc, net80211_step_associate, - &netdev->refcnt ); - INIT_LIST_HEAD ( &dev->mgmt_queue ); - INIT_LIST_HEAD ( &dev->mgmt_info_queue ); - - return dev; -} - -/** - * Register 802.11 device with network stack - * - * @v dev 802.11 device - * @v ops 802.11 device operations - * @v hw 802.11 hardware information - * - * This also registers the wrapping net_device with the higher network - * layers. - */ -int net80211_register ( struct net80211_device *dev, - struct net80211_device_operations *ops, - struct net80211_hw_info *hw ) -{ - dev->op = ops; - dev->hw = malloc ( sizeof ( *hw ) ); - if ( ! dev->hw ) - return -ENOMEM; - - memcpy ( dev->hw, hw, sizeof ( *hw ) ); - memcpy ( dev->netdev->hw_addr, hw->hwaddr, ETH_ALEN ); - - /* Set some sensible channel defaults for driver's open() function */ - memcpy ( dev->channels, dev->hw->channels, - NET80211_MAX_CHANNELS * sizeof ( dev->channels[0] ) ); - dev->channel = 0; - - list_add_tail ( &dev->list, &net80211_devices ); - return register_netdev ( dev->netdev ); -} - -/** - * Unregister 802.11 device from network stack - * - * @v dev 802.11 device - * - * After this call, the device operations are cleared so that they - * will not be called. - */ -void net80211_unregister ( struct net80211_device *dev ) -{ - unregister_netdev ( dev->netdev ); - list_del ( &dev->list ); - dev->op = &net80211_null_ops; -} - -/** - * Free 802.11 device - * - * @v dev 802.11 device - * - * The device should be unregistered before this function is called. - */ -void net80211_free ( struct net80211_device *dev ) -{ - free ( dev->hw ); - rc80211_free ( dev->rctl ); - netdev_nullify ( dev->netdev ); - netdev_put ( dev->netdev ); -} - - -/* ---------- 802.11 network management workhorse code ---------- */ - -/** - * Set state of 802.11 device - * - * @v dev 802.11 device - * @v clear Bitmask of flags to clear - * @v set Bitmask of flags to set - * @v status Status or reason code for most recent operation - * - * If @a status represents a reason code, it should be OR'ed with - * NET80211_IS_REASON. - * - * Clearing authentication also clears association; clearing - * association also clears security handshaking state. Clearing - * association removes the link-up flag from the wrapping net_device, - * but setting it does not automatically set the flag; that is left to - * the judgment of higher-level code. - */ -static inline void net80211_set_state ( struct net80211_device *dev, - short clear, short set, - u16 status ) -{ - /* The conditions in this function are deliberately formulated - to be decidable at compile-time in most cases. Since clear - and set are generally passed as constants, the body of this - function can be reduced down to a few statements by the - compiler. */ - - const int statmsk = NET80211_STATUS_MASK | NET80211_IS_REASON; - - if ( clear & NET80211_PROBED ) - clear |= NET80211_AUTHENTICATED; - - if ( clear & NET80211_AUTHENTICATED ) - clear |= NET80211_ASSOCIATED; - - if ( clear & NET80211_ASSOCIATED ) - clear |= NET80211_CRYPTO_SYNCED; - - dev->state = ( dev->state & ~clear ) | set; - dev->state = ( dev->state & ~statmsk ) | ( status & statmsk ); - - if ( clear & NET80211_ASSOCIATED ) - netdev_link_down ( dev->netdev ); - - if ( ( clear | set ) & NET80211_ASSOCIATED ) - dev->op->config ( dev, NET80211_CFG_ASSOC ); - - if ( status != 0 ) { - if ( status & NET80211_IS_REASON ) - dev->assoc_rc = -E80211_REASON ( status ); - else - dev->assoc_rc = -E80211_STATUS ( status ); - netdev_link_err ( dev->netdev, dev->assoc_rc ); - } -} - -/** - * Add channels to 802.11 device - * - * @v dev 802.11 device - * @v start First channel number to add - * @v len Number of channels to add - * @v txpower TX power (dBm) to allow on added channels - * - * To replace the current list of channels instead of adding to it, - * set the nr_channels field of the 802.11 device to 0 before calling - * this function. - */ -static void net80211_add_channels ( struct net80211_device *dev, int start, - int len, int txpower ) -{ - int i, chan = start; - - for ( i = dev->nr_channels; len-- && i < NET80211_MAX_CHANNELS; i++ ) { - dev->channels[i].channel_nr = chan; - dev->channels[i].maxpower = txpower; - dev->channels[i].hw_value = 0; - - if ( chan >= 1 && chan <= 14 ) { - dev->channels[i].band = NET80211_BAND_2GHZ; - if ( chan == 14 ) - dev->channels[i].center_freq = 2484; - else - dev->channels[i].center_freq = 2407 + 5 * chan; - chan++; - } else { - dev->channels[i].band = NET80211_BAND_5GHZ; - dev->channels[i].center_freq = 5000 + 5 * chan; - chan += 4; - } - } - - dev->nr_channels = i; -} - -/** - * Filter 802.11 device channels for hardware capabilities - * - * @v dev 802.11 device - * - * Hardware may support fewer channels than regulatory restrictions - * allow; this function filters out channels in dev->channels that are - * not supported by the hardware list in dev->hwinfo. It also copies - * over the net80211_channel::hw_value and limits maximum TX power - * appropriately. - * - * Channels are matched based on center frequency, ignoring band and - * channel number. - * - * If the driver specifies no supported channels, the effect will be - * as though all were supported. - */ -static void net80211_filter_hw_channels ( struct net80211_device *dev ) -{ - int delta = 0, i = 0; - int old_freq = dev->channels[dev->channel].center_freq; - struct net80211_channel *chan, *hwchan; - - if ( ! dev->hw->nr_channels ) - return; - - dev->channel = 0; - for ( chan = dev->channels; chan < dev->channels + dev->nr_channels; - chan++, i++ ) { - int ok = 0; - for ( hwchan = dev->hw->channels; - hwchan < dev->hw->channels + dev->hw->nr_channels; - hwchan++ ) { - if ( hwchan->center_freq == chan->center_freq ) { - ok = 1; - break; - } - } - - if ( ! ok ) - delta++; - else { - chan->hw_value = hwchan->hw_value; - if ( hwchan->maxpower != 0 && - chan->maxpower > hwchan->maxpower ) - chan->maxpower = hwchan->maxpower; - if ( old_freq == chan->center_freq ) - dev->channel = i - delta; - if ( delta ) - chan[-delta] = *chan; - } - } - - dev->nr_channels -= delta; - - if ( dev->channels[dev->channel].center_freq != old_freq ) - dev->op->config ( dev, NET80211_CFG_CHANNEL ); -} - -/** - * Update 802.11 device state to reflect received capabilities field - * - * @v dev 802.11 device - * @v capab Capabilities field in beacon, probe, or association frame - * @ret rc Return status code - */ -static int net80211_process_capab ( struct net80211_device *dev, - u16 capab ) -{ - u16 old_phy = dev->phy_flags; - - if ( ( capab & ( IEEE80211_CAPAB_MANAGED | IEEE80211_CAPAB_ADHOC ) ) != - IEEE80211_CAPAB_MANAGED ) { - DBGC ( dev, "802.11 %p cannot handle IBSS network\n", dev ); - return -ENOSYS; - } - - dev->phy_flags &= ~( NET80211_PHY_USE_SHORT_PREAMBLE | - NET80211_PHY_USE_SHORT_SLOT ); - - if ( capab & IEEE80211_CAPAB_SHORT_PMBL ) - dev->phy_flags |= NET80211_PHY_USE_SHORT_PREAMBLE; - - if ( capab & IEEE80211_CAPAB_SHORT_SLOT ) - dev->phy_flags |= NET80211_PHY_USE_SHORT_SLOT; - - if ( old_phy != dev->phy_flags ) - dev->op->config ( dev, NET80211_CFG_PHY_PARAMS ); - - return 0; -} - -/** - * Update 802.11 device state to reflect received information elements - * - * @v dev 802.11 device - * @v ie Pointer to first information element - * @v ie_end Pointer to tail of packet I/O buffer - * @ret rc Return status code - */ -static int net80211_process_ie ( struct net80211_device *dev, - union ieee80211_ie *ie, void *ie_end ) -{ - u16 old_rate = dev->rates[dev->rate]; - u16 old_phy = dev->phy_flags; - int have_rates = 0, i; - int ds_channel = 0; - int changed = 0; - int band = dev->channels[dev->channel].band; - - if ( ! ieee80211_ie_bound ( ie, ie_end ) ) - return 0; - - for ( ; ie; ie = ieee80211_next_ie ( ie, ie_end ) ) { - switch ( ie->id ) { - case IEEE80211_IE_SSID: - if ( ie->len <= 32 ) { - memcpy ( dev->essid, ie->ssid, ie->len ); - dev->essid[ie->len] = 0; - } - break; - - case IEEE80211_IE_RATES: - case IEEE80211_IE_EXT_RATES: - if ( ! have_rates ) { - dev->nr_rates = 0; - dev->basic_rates = 0; - have_rates = 1; - } - for ( i = 0; i < ie->len && - dev->nr_rates < NET80211_MAX_RATES; i++ ) { - u8 rid = ie->rates[i]; - u16 rate = ( rid & 0x7f ) * 5; - - if ( rid & 0x80 ) - dev->basic_rates |= - ( 1 << dev->nr_rates ); - - dev->rates[dev->nr_rates++] = rate; - } - - break; - - case IEEE80211_IE_DS_PARAM: - if ( dev->channel < dev->nr_channels && ds_channel == - dev->channels[dev->channel].channel_nr ) - break; - ds_channel = ie->ds_param.current_channel; - net80211_change_channel ( dev, ds_channel ); - break; - - case IEEE80211_IE_COUNTRY: - dev->nr_channels = 0; - - DBGC ( dev, "802.11 %p setting country regulations " - "for %c%c\n", dev, ie->country.name[0], - ie->country.name[1] ); - for ( i = 0; i < ( ie->len - 3 ) / 3; i++ ) { - union ieee80211_ie_country_triplet *t = - &ie->country.triplet[i]; - if ( t->first > 200 ) { - DBGC ( dev, "802.11 %p ignoring regulatory " - "extension information\n", dev ); - } else { - net80211_add_channels ( dev, - t->band.first_channel, - t->band.nr_channels, - t->band.max_txpower ); - } - } - net80211_filter_hw_channels ( dev ); - break; - - case IEEE80211_IE_ERP_INFO: - dev->phy_flags &= ~( NET80211_PHY_USE_PROTECTION | - NET80211_PHY_USE_SHORT_PREAMBLE ); - if ( ie->erp_info & IEEE80211_ERP_USE_PROTECTION ) - dev->phy_flags |= NET80211_PHY_USE_PROTECTION; - if ( ! ( ie->erp_info & IEEE80211_ERP_BARKER_LONG ) ) - dev->phy_flags |= NET80211_PHY_USE_SHORT_PREAMBLE; - break; - } - } - - if ( have_rates ) { - /* Allow only those rates that are also supported by - the hardware. */ - int delta = 0, j; - - dev->rate = 0; - for ( i = 0; i < dev->nr_rates; i++ ) { - int ok = 0; - for ( j = 0; j < dev->hw->nr_rates[band]; j++ ) { - if ( dev->hw->rates[band][j] == dev->rates[i] ){ - ok = 1; - break; - } - } - - if ( ! ok ) - delta++; - else { - dev->rates[i - delta] = dev->rates[i]; - if ( old_rate == dev->rates[i] ) - dev->rate = i - delta; - } - } - - dev->nr_rates -= delta; - - /* Sort available rates - sorted subclumps tend to already - exist, so insertion sort works well. */ - for ( i = 1; i < dev->nr_rates; i++ ) { - u16 rate = dev->rates[i]; - u32 tmp, br, mask; - - for ( j = i - 1; j >= 0 && dev->rates[j] >= rate; j-- ) - dev->rates[j + 1] = dev->rates[j]; - dev->rates[j + 1] = rate; - - /* Adjust basic_rates to match by rotating the - bits from bit j+1 to bit i left one position. */ - mask = ( ( 1 << i ) - 1 ) & ~( ( 1 << ( j + 1 ) ) - 1 ); - br = dev->basic_rates; - tmp = br & ( 1 << i ); - br = ( br & ~( mask | tmp ) ) | ( ( br & mask ) << 1 ); - br |= ( tmp >> ( i - j - 1 ) ); - dev->basic_rates = br; - } - - net80211_set_rtscts_rate ( dev ); - - if ( dev->rates[dev->rate] != old_rate ) - changed |= NET80211_CFG_RATE; - } - - if ( dev->hw->flags & NET80211_HW_NO_SHORT_PREAMBLE ) - dev->phy_flags &= ~NET80211_PHY_USE_SHORT_PREAMBLE; - if ( dev->hw->flags & NET80211_HW_NO_SHORT_SLOT ) - dev->phy_flags &= ~NET80211_PHY_USE_SHORT_SLOT; - - if ( old_phy != dev->phy_flags ) - changed |= NET80211_CFG_PHY_PARAMS; - - if ( changed ) - dev->op->config ( dev, changed ); - - return 0; -} - -/** - * Create information elements for outgoing probe or association packet - * - * @v dev 802.11 device - * @v ie Pointer to start of information element area - * @ret next_ie Pointer to first byte after added information elements - */ -static union ieee80211_ie * -net80211_marshal_request_info ( struct net80211_device *dev, - union ieee80211_ie *ie ) -{ - int i; - - ie->id = IEEE80211_IE_SSID; - ie->len = strlen ( dev->essid ); - memcpy ( ie->ssid, dev->essid, ie->len ); - - ie = ieee80211_next_ie ( ie, NULL ); - - ie->id = IEEE80211_IE_RATES; - ie->len = dev->nr_rates; - if ( ie->len > 8 ) - ie->len = 8; - - for ( i = 0; i < ie->len; i++ ) { - ie->rates[i] = dev->rates[i] / 5; - if ( dev->basic_rates & ( 1 << i ) ) - ie->rates[i] |= 0x80; - } - - ie = ieee80211_next_ie ( ie, NULL ); - - if ( dev->rsn_ie && dev->rsn_ie->id == IEEE80211_IE_RSN ) { - memcpy ( ie, dev->rsn_ie, dev->rsn_ie->len + 2 ); - ie = ieee80211_next_ie ( ie, NULL ); - } - - if ( dev->nr_rates > 8 ) { - /* 802.11 requires we use an Extended Basic Rates IE - for the rates beyond the eighth. */ - - ie->id = IEEE80211_IE_EXT_RATES; - ie->len = dev->nr_rates - 8; - - for ( ; i < dev->nr_rates; i++ ) { - ie->rates[i - 8] = dev->rates[i] / 5; - if ( dev->basic_rates & ( 1 << i ) ) - ie->rates[i - 8] |= 0x80; - } - - ie = ieee80211_next_ie ( ie, NULL ); - } - - if ( dev->rsn_ie && dev->rsn_ie->id == IEEE80211_IE_VENDOR ) { - memcpy ( ie, dev->rsn_ie, dev->rsn_ie->len + 2 ); - ie = ieee80211_next_ie ( ie, NULL ); - } - - return ie; -} - -/** Seconds to wait after finding a network, to possibly find better APs for it - * - * This is used when a specific SSID to scan for is specified. - */ -#define NET80211_PROBE_GATHER 1 - -/** Seconds to wait after finding a network, to possibly find other networks - * - * This is used when an empty SSID is specified, to scan for all - * networks. - */ -#define NET80211_PROBE_GATHER_ALL 2 - -/** Seconds to allow a probe to take if no network has been found */ -#define NET80211_PROBE_TIMEOUT 6 - -/** - * Begin probe of 802.11 networks - * - * @v dev 802.11 device - * @v essid SSID to probe for, or "" to accept any (may not be NULL) - * @v active Whether to use active scanning - * @ret ctx Probe context - * - * Active scanning may only be used on channels 1-11 in the 2.4GHz - * band, due to gPXE's lack of a complete regulatory database. If - * active scanning is used, probe packets will be sent on each - * channel; this can allow association with hidden-SSID networks if - * the SSID is properly specified. - * - * A @c NULL return indicates an out-of-memory condition. - * - * The returned context must be periodically passed to - * net80211_probe_step() until that function returns zero. - */ -struct net80211_probe_ctx * net80211_probe_start ( struct net80211_device *dev, - const char *essid, - int active ) -{ - struct net80211_probe_ctx *ctx = zalloc ( sizeof ( *ctx ) ); - - if ( ! ctx ) - return NULL; - - assert ( dev->netdev->state & NETDEV_OPEN ); - - ctx->dev = dev; - ctx->old_keep_mgmt = net80211_keep_mgmt ( dev, 1 ); - ctx->essid = essid; - if ( dev->essid != ctx->essid ) - strcpy ( dev->essid, ctx->essid ); - - if ( active ) { - struct ieee80211_probe_req *probe_req; - union ieee80211_ie *ie; - - ctx->probe = alloc_iob ( 128 ); - iob_reserve ( ctx->probe, IEEE80211_TYP_FRAME_HEADER_LEN ); - probe_req = ctx->probe->data; - - ie = net80211_marshal_request_info ( dev, - probe_req->info_element ); - - iob_put ( ctx->probe, ( void * ) ie - ctx->probe->data ); - } - - ctx->ticks_start = currticks(); - ctx->ticks_beacon = 0; - ctx->ticks_channel = currticks(); - ctx->hop_time = ticks_per_sec() / ( active ? 2 : 6 ); - - /* - * Channels on 2.4GHz overlap, and the most commonly used - * are 1, 6, and 11. We'll get a result faster if we check - * every 5 channels, but in order to hit all of them the - * number of channels must be relatively prime to 5. If it's - * not, tweak the hop. - */ - ctx->hop_step = 5; - while ( dev->nr_channels % ctx->hop_step == 0 && ctx->hop_step > 1 ) - ctx->hop_step--; - - ctx->beacons = malloc ( sizeof ( *ctx->beacons ) ); - INIT_LIST_HEAD ( ctx->beacons ); - - dev->channel = 0; - dev->op->config ( dev, NET80211_CFG_CHANNEL ); - - return ctx; -} - -/** - * Continue probe of 802.11 networks - * - * @v ctx Probe context returned by net80211_probe_start() - * @ret rc Probe status - * - * The return code will be 0 if the probe is still going on (and this - * function should be called again), a positive number if the probe - * completed successfully, or a negative error code if the probe - * failed for that reason. - * - * Whether the probe succeeded or failed, you must call - * net80211_probe_finish_all() or net80211_probe_finish_best() - * (depending on whether you want information on all networks or just - * the best-signal one) in order to release the probe context. A - * failed probe may still have acquired some valid data. - */ -int net80211_probe_step ( struct net80211_probe_ctx *ctx ) -{ - struct net80211_device *dev = ctx->dev; - u32 start_timeout = NET80211_PROBE_TIMEOUT * ticks_per_sec(); - u32 gather_timeout = ticks_per_sec(); - u32 now = currticks(); - struct io_buffer *iob; - int signal; - int rc; - char ssid[IEEE80211_MAX_SSID_LEN + 1]; - - gather_timeout *= ( ctx->essid[0] ? NET80211_PROBE_GATHER : - NET80211_PROBE_GATHER_ALL ); - - /* Time out if necessary */ - if ( now >= ctx->ticks_start + start_timeout ) - return list_empty ( ctx->beacons ) ? -ETIMEDOUT : +1; - - if ( ctx->ticks_beacon > 0 && now >= ctx->ticks_start + gather_timeout ) - return +1; - - /* Change channels if necessary */ - if ( now >= ctx->ticks_channel + ctx->hop_time ) { - dev->channel = ( dev->channel + ctx->hop_step ) - % dev->nr_channels; - dev->op->config ( dev, NET80211_CFG_CHANNEL ); - udelay ( dev->hw->channel_change_time ); - - ctx->ticks_channel = now; - - if ( ctx->probe ) { - struct io_buffer *siob = ctx->probe; /* to send */ - - /* make a copy for future use */ - iob = alloc_iob ( siob->tail - siob->head ); - iob_reserve ( iob, iob_headroom ( siob ) ); - memcpy ( iob_put ( iob, iob_len ( siob ) ), - siob->data, iob_len ( siob ) ); - - ctx->probe = iob; - rc = net80211_tx_mgmt ( dev, IEEE80211_STYPE_PROBE_REQ, - net80211_ll_broadcast, - iob_disown ( siob ) ); - if ( rc ) { - DBGC ( dev, "802.11 %p send probe failed: " - "%s\n", dev, strerror ( rc ) ); - return rc; - } - } - } - - /* Check for new management packets */ - while ( ( iob = net80211_mgmt_dequeue ( dev, &signal ) ) != NULL ) { - struct ieee80211_frame *hdr; - struct ieee80211_beacon *beacon; - union ieee80211_ie *ie; - struct net80211_wlan *wlan; - u16 type; - - hdr = iob->data; - type = hdr->fc & IEEE80211_FC_SUBTYPE; - beacon = ( struct ieee80211_beacon * ) hdr->data; - - if ( type != IEEE80211_STYPE_BEACON && - type != IEEE80211_STYPE_PROBE_RESP ) { - DBGC2 ( dev, "802.11 %p probe: non-beacon\n", dev ); - goto drop; - } - - if ( ( void * ) beacon->info_element >= iob->tail ) { - DBGC ( dev, "802.11 %p probe: beacon with no IEs\n", - dev ); - goto drop; - } - - ie = beacon->info_element; - - if ( ! ieee80211_ie_bound ( ie, iob->tail ) ) - ie = NULL; - - while ( ie && ie->id != IEEE80211_IE_SSID ) - ie = ieee80211_next_ie ( ie, iob->tail ); - - if ( ! ie ) { - DBGC ( dev, "802.11 %p probe: beacon with no SSID\n", - dev ); - goto drop; - } - - memcpy ( ssid, ie->ssid, ie->len ); - ssid[ie->len] = 0; - - if ( ctx->essid[0] && strcmp ( ctx->essid, ssid ) != 0 ) { - DBGC2 ( dev, "802.11 %p probe: beacon with wrong SSID " - "(%s)\n", dev, ssid ); - goto drop; - } - - /* See if we've got an entry for this network */ - list_for_each_entry ( wlan, ctx->beacons, list ) { - if ( strcmp ( wlan->essid, ssid ) != 0 ) - continue; - - if ( signal < wlan->signal ) { - DBGC2 ( dev, "802.11 %p probe: beacon for %s " - "(%s) with weaker signal %d\n", dev, - ssid, eth_ntoa ( hdr->addr3 ), signal ); - goto drop; - } - - goto fill; - } - - /* No entry yet - make one */ - wlan = zalloc ( sizeof ( *wlan ) ); - strcpy ( wlan->essid, ssid ); - list_add_tail ( &wlan->list, ctx->beacons ); - - /* Whether we're using an old entry or a new one, fill - it with new data. */ - fill: - memcpy ( wlan->bssid, hdr->addr3, ETH_ALEN ); - wlan->signal = signal; - wlan->channel = dev->channels[dev->channel].channel_nr; - - /* Copy this I/O buffer into a new wlan->beacon; the - * iob we've got probably came from the device driver - * and may have the full 2.4k allocation, which we - * don't want to keep around wasting memory. - */ - free_iob ( wlan->beacon ); - wlan->beacon = alloc_iob ( iob_len ( iob ) ); - memcpy ( iob_put ( wlan->beacon, iob_len ( iob ) ), - iob->data, iob_len ( iob ) ); - - if ( ( rc = sec80211_detect ( wlan->beacon, &wlan->handshaking, - &wlan->crypto ) ) == -ENOTSUP ) { - struct ieee80211_beacon *beacon = - ( struct ieee80211_beacon * ) hdr->data; - - if ( beacon->capability & IEEE80211_CAPAB_PRIVACY ) { - DBG ( "802.11 %p probe: secured network %s but " - "encryption support not compiled in\n", - dev, wlan->essid ); - wlan->handshaking = NET80211_SECPROT_UNKNOWN; - wlan->crypto = NET80211_CRYPT_UNKNOWN; - } else { - wlan->handshaking = NET80211_SECPROT_NONE; - wlan->crypto = NET80211_CRYPT_NONE; - } - } else if ( rc != 0 ) { - DBGC ( dev, "802.11 %p probe warning: network " - "%s with unidentifiable security " - "settings: %s\n", dev, wlan->essid, - strerror ( rc ) ); - } - - ctx->ticks_beacon = now; - - DBGC2 ( dev, "802.11 %p probe: good beacon for %s (%s)\n", - dev, wlan->essid, eth_ntoa ( wlan->bssid ) ); - - drop: - free_iob ( iob ); - } - - return 0; -} - - -/** - * Finish probe of 802.11 networks, returning best-signal network found - * - * @v ctx Probe context - * @ret wlan Best-signal network found, or @c NULL if none were found - * - * If net80211_probe_start() was called with a particular SSID - * parameter as filter, only a network with that SSID (matching - * case-sensitively) can be returned from this function. - */ -struct net80211_wlan * -net80211_probe_finish_best ( struct net80211_probe_ctx *ctx ) -{ - struct net80211_wlan *best = NULL, *wlan; - - if ( ! ctx ) - return NULL; - - list_for_each_entry ( wlan, ctx->beacons, list ) { - if ( ! best || best->signal < wlan->signal ) - best = wlan; - } - - if ( best ) - list_del ( &best->list ); - else - DBGC ( ctx->dev, "802.11 %p probe: found nothing for '%s'\n", - ctx->dev, ctx->essid ); - - net80211_free_wlanlist ( ctx->beacons ); - - net80211_keep_mgmt ( ctx->dev, ctx->old_keep_mgmt ); - - if ( ctx->probe ) - free_iob ( ctx->probe ); - - free ( ctx ); - - return best; -} - - -/** - * Finish probe of 802.11 networks, returning all networks found - * - * @v ctx Probe context - * @ret list List of net80211_wlan detailing networks found - * - * If net80211_probe_start() was called with a particular SSID - * parameter as filter, this will always return either an empty or a - * one-element list. - */ -struct list_head *net80211_probe_finish_all ( struct net80211_probe_ctx *ctx ) -{ - struct list_head *beacons = ctx->beacons; - - if ( ! ctx ) - return NULL; - - net80211_keep_mgmt ( ctx->dev, ctx->old_keep_mgmt ); - - if ( ctx->probe ) - free_iob ( ctx->probe ); - - free ( ctx ); - - return beacons; -} - - -/** - * Free WLAN structure - * - * @v wlan WLAN structure to free - */ -void net80211_free_wlan ( struct net80211_wlan *wlan ) -{ - if ( wlan ) { - free_iob ( wlan->beacon ); - free ( wlan ); - } -} - - -/** - * Free list of WLAN structures - * - * @v list List of WLAN structures to free - */ -void net80211_free_wlanlist ( struct list_head *list ) -{ - struct net80211_wlan *wlan, *tmp; - - if ( ! list ) - return; - - list_for_each_entry_safe ( wlan, tmp, list, list ) { - list_del ( &wlan->list ); - net80211_free_wlan ( wlan ); - } - - free ( list ); -} - - -/** Number of ticks to wait for replies to association management frames */ -#define ASSOC_TIMEOUT TICKS_PER_SEC - -/** Number of times to try sending a particular association management frame */ -#define ASSOC_RETRIES 2 - -/** - * Step 802.11 association process - * - * @v proc Association process - */ -static void net80211_step_associate ( struct process *proc ) -{ - struct net80211_device *dev = - container_of ( proc, struct net80211_device, proc_assoc ); - int rc = 0; - int status = dev->state & NET80211_STATUS_MASK; - - /* - * We use a sort of state machine implemented using bits in - * the dev->state variable. At each call, we take the - * logically first step that has not yet succeeded; either it - * has not been tried yet, it's being retried, or it failed. - * If it failed, we return an error indication; otherwise we - * perform the step. If it succeeds, RX handling code will set - * the appropriate status bit for us. - * - * Probe works a bit differently, since we have to step it - * on every call instead of waiting for a packet to arrive - * that will set the completion bit for us. - */ - - /* If we're waiting for a reply, check for timeout condition */ - if ( dev->state & NET80211_WAITING ) { - /* Sanity check */ - if ( ! dev->associating ) - return; - - if ( currticks() - dev->ctx.assoc->last_packet > ASSOC_TIMEOUT ) { - /* Timed out - fail if too many retries, or retry */ - dev->ctx.assoc->times_tried++; - if ( ++dev->ctx.assoc->times_tried > ASSOC_RETRIES ) { - rc = -ETIMEDOUT; - goto fail; - } - } else { - /* Didn't time out - let it keep going */ - return; - } - } else { - if ( dev->state & NET80211_PROBED ) - dev->ctx.assoc->times_tried = 0; - } - - if ( ! ( dev->state & NET80211_PROBED ) ) { - /* state: probe */ - - if ( ! dev->ctx.probe ) { - /* start probe */ - int active = fetch_intz_setting ( NULL, - &net80211_active_setting ); - int band = dev->hw->bands; - - if ( active ) - band &= ~NET80211_BAND_BIT_5GHZ; - - rc = net80211_prepare_probe ( dev, band, active ); - if ( rc ) - goto fail; - - dev->ctx.probe = net80211_probe_start ( dev, dev->essid, - active ); - if ( ! dev->ctx.probe ) { - dev->assoc_rc = -ENOMEM; - goto fail; - } - } - - rc = net80211_probe_step ( dev->ctx.probe ); - if ( ! rc ) { - return; /* still going */ - } - - dev->associating = net80211_probe_finish_best ( dev->ctx.probe ); - dev->ctx.probe = NULL; - if ( ! dev->associating ) { - if ( rc > 0 ) /* "successful" probe found nothing */ - rc = -ETIMEDOUT; - goto fail; - } - - /* If we probed using a broadcast SSID, record that - fact for the settings applicator before we clobber - it with the specific SSID we've chosen. */ - if ( ! dev->essid[0] ) - dev->state |= NET80211_AUTO_SSID; - - DBGC ( dev, "802.11 %p found network %s (%s)\n", dev, - dev->associating->essid, - eth_ntoa ( dev->associating->bssid ) ); - - dev->ctx.assoc = zalloc ( sizeof ( *dev->ctx.assoc ) ); - if ( ! dev->ctx.assoc ) { - rc = -ENOMEM; - goto fail; - } - - dev->state |= NET80211_PROBED; - dev->ctx.assoc->method = IEEE80211_AUTH_OPEN_SYSTEM; - - return; - } - - /* Record time of sending the packet we're about to send, for timeout */ - dev->ctx.assoc->last_packet = currticks(); - - if ( ! ( dev->state & NET80211_AUTHENTICATED ) ) { - /* state: prepare and authenticate */ - - if ( status != IEEE80211_STATUS_SUCCESS ) { - /* we tried authenticating already, but failed */ - int method = dev->ctx.assoc->method; - - if ( method == IEEE80211_AUTH_OPEN_SYSTEM && - ( status == IEEE80211_STATUS_AUTH_CHALL_INVALID || - status == IEEE80211_STATUS_AUTH_ALGO_UNSUPP ) ) { - /* Maybe this network uses Shared Key? */ - dev->ctx.assoc->method = - IEEE80211_AUTH_SHARED_KEY; - } else { - goto fail; - } - } - - DBGC ( dev, "802.11 %p authenticating with method %d\n", dev, - dev->ctx.assoc->method ); - - rc = net80211_prepare_assoc ( dev, dev->associating ); - if ( rc ) - goto fail; - - rc = net80211_send_auth ( dev, dev->associating, - dev->ctx.assoc->method ); - if ( rc ) - goto fail; - - return; - } - - if ( ! ( dev->state & NET80211_ASSOCIATED ) ) { - /* state: associate */ - - if ( status != IEEE80211_STATUS_SUCCESS ) - goto fail; - - DBGC ( dev, "802.11 %p associating\n", dev ); - - if ( dev->handshaker && dev->handshaker->start && - ! dev->handshaker->started ) { - rc = dev->handshaker->start ( dev ); - if ( rc < 0 ) - goto fail; - dev->handshaker->started = 1; - } - - rc = net80211_send_assoc ( dev, dev->associating ); - if ( rc ) - goto fail; - - return; - } - - if ( ! ( dev->state & NET80211_CRYPTO_SYNCED ) ) { - /* state: crypto sync */ - DBGC ( dev, "802.11 %p security handshaking\n", dev ); - - if ( ! dev->handshaker || ! dev->handshaker->step ) { - dev->state |= NET80211_CRYPTO_SYNCED; - return; - } - - rc = dev->handshaker->step ( dev ); - - if ( rc < 0 ) { - /* Only record the returned error if we're - still marked as associated, because an - asynchronous error will have already been - reported to net80211_deauthenticate() and - assoc_rc thereby set. */ - if ( dev->state & NET80211_ASSOCIATED ) - dev->assoc_rc = rc; - rc = 0; - goto fail; - } - - if ( rc > 0 ) { - dev->assoc_rc = 0; - dev->state |= NET80211_CRYPTO_SYNCED; - } - return; - } - - /* state: done! */ - netdev_link_up ( dev->netdev ); - dev->assoc_rc = 0; - dev->state &= ~NET80211_WORKING; - - free ( dev->ctx.assoc ); - dev->ctx.assoc = NULL; - - net80211_free_wlan ( dev->associating ); - dev->associating = NULL; - - dev->rctl = rc80211_init ( dev ); - - process_del ( proc ); - - DBGC ( dev, "802.11 %p associated with %s (%s)\n", dev, - dev->essid, eth_ntoa ( dev->bssid ) ); - - return; - - fail: - dev->state &= ~( NET80211_WORKING | NET80211_WAITING ); - if ( rc ) - dev->assoc_rc = rc; - - netdev_link_err ( dev->netdev, dev->assoc_rc ); - - /* We never reach here from the middle of a probe, so we don't - need to worry about freeing dev->ctx.probe. */ - - if ( dev->state & NET80211_PROBED ) { - free ( dev->ctx.assoc ); - dev->ctx.assoc = NULL; - } - - net80211_free_wlan ( dev->associating ); - dev->associating = NULL; - - process_del ( proc ); - - DBGC ( dev, "802.11 %p association failed (state=%04x): " - "%s\n", dev, dev->state, strerror ( dev->assoc_rc ) ); - - /* Try it again: */ - net80211_autoassociate ( dev ); -} - -/** - * Check for 802.11 SSID or key updates - * - * This acts as a settings applicator; if the user changes netX/ssid, - * and netX is currently open, the association task will be invoked - * again. If the user changes the encryption key, the current security - * handshaker will be asked to update its state to match; if that is - * impossible without reassociation, we reassociate. - */ -static int net80211_check_settings_update ( void ) -{ - struct net80211_device *dev; - char ssid[IEEE80211_MAX_SSID_LEN + 1]; - int key_reassoc; - - list_for_each_entry ( dev, &net80211_devices, list ) { - if ( ! ( dev->netdev->state & NETDEV_OPEN ) ) - continue; - - key_reassoc = 0; - if ( dev->handshaker && dev->handshaker->change_key && - dev->handshaker->change_key ( dev ) < 0 ) - key_reassoc = 1; - - fetch_string_setting ( netdev_settings ( dev->netdev ), - &net80211_ssid_setting, ssid, - IEEE80211_MAX_SSID_LEN + 1 ); - - if ( key_reassoc || - ( ! ( ! ssid[0] && ( dev->state & NET80211_AUTO_SSID ) ) && - strcmp ( ssid, dev->essid ) != 0 ) ) { - DBGC ( dev, "802.11 %p updating association: " - "%s -> %s\n", dev, dev->essid, ssid ); - net80211_autoassociate ( dev ); - } - } - - return 0; -} - -/** - * Start 802.11 association process - * - * @v dev 802.11 device - * - * If the association process is running, it will be restarted. - */ -void net80211_autoassociate ( struct net80211_device *dev ) -{ - if ( ! ( dev->state & NET80211_WORKING ) ) { - DBGC2 ( dev, "802.11 %p spawning association process\n", dev ); - process_add ( &dev->proc_assoc ); - } else { - DBGC2 ( dev, "802.11 %p restarting association\n", dev ); - } - - /* Clean up everything an earlier association process might - have been in the middle of using */ - if ( dev->associating ) - net80211_free_wlan ( dev->associating ); - - if ( ! ( dev->state & NET80211_PROBED ) ) - net80211_free_wlan ( - net80211_probe_finish_best ( dev->ctx.probe ) ); - else - free ( dev->ctx.assoc ); - - /* Reset to a clean state */ - fetch_string_setting ( netdev_settings ( dev->netdev ), - &net80211_ssid_setting, dev->essid, - IEEE80211_MAX_SSID_LEN + 1 ); - dev->ctx.probe = NULL; - dev->associating = NULL; - dev->assoc_rc = 0; - net80211_set_state ( dev, NET80211_PROBED, NET80211_WORKING, 0 ); -} - -/** - * Pick TX rate for RTS/CTS packets based on data rate - * - * @v dev 802.11 device - * - * The RTS/CTS rate is the fastest TX rate marked as "basic" that is - * not faster than the data rate. - */ -static void net80211_set_rtscts_rate ( struct net80211_device *dev ) -{ - u16 datarate = dev->rates[dev->rate]; - u16 rtsrate = 0; - int rts_idx = -1; - int i; - - for ( i = 0; i < dev->nr_rates; i++ ) { - u16 rate = dev->rates[i]; - - if ( ! ( dev->basic_rates & ( 1 << i ) ) || rate > datarate ) - continue; - - if ( rate > rtsrate ) { - rtsrate = rate; - rts_idx = i; - } - } - - /* If this is in initialization, we might not have any basic - rates; just use the first data rate in that case. */ - if ( rts_idx < 0 ) - rts_idx = 0; - - dev->rtscts_rate = rts_idx; -} - -/** - * Set data transmission rate for 802.11 device - * - * @v dev 802.11 device - * @v rate Rate to set, as index into @c dev->rates array - */ -void net80211_set_rate_idx ( struct net80211_device *dev, int rate ) -{ - assert ( dev->netdev->state & NETDEV_OPEN ); - - if ( rate >= 0 && rate < dev->nr_rates && rate != dev->rate ) { - DBGC2 ( dev, "802.11 %p changing rate from %d->%d Mbps\n", - dev, dev->rates[dev->rate] / 10, - dev->rates[rate] / 10 ); - - dev->rate = rate; - net80211_set_rtscts_rate ( dev ); - dev->op->config ( dev, NET80211_CFG_RATE ); - } -} - -/** - * Configure 802.11 device to transmit on a certain channel - * - * @v dev 802.11 device - * @v channel Channel number (1-11 for 2.4GHz) to transmit on - */ -int net80211_change_channel ( struct net80211_device *dev, int channel ) -{ - int i, oldchan = dev->channel; - - assert ( dev->netdev->state & NETDEV_OPEN ); - - for ( i = 0; i < dev->nr_channels; i++ ) { - if ( dev->channels[i].channel_nr == channel ) { - dev->channel = i; - break; - } - } - - if ( i == dev->nr_channels ) - return -ENOENT; - - if ( i != oldchan ) - return dev->op->config ( dev, NET80211_CFG_CHANNEL ); - - return 0; -} - -/** - * Prepare 802.11 device channel and rate set for scanning - * - * @v dev 802.11 device - * @v band RF band(s) on which to prepare for scanning - * @v active Whether the scanning will be active - * @ret rc Return status code - */ -int net80211_prepare_probe ( struct net80211_device *dev, int band, - int active ) -{ - assert ( dev->netdev->state & NETDEV_OPEN ); - - if ( active && ( band & NET80211_BAND_BIT_5GHZ ) ) { - DBGC ( dev, "802.11 %p cannot perform active scanning on " - "5GHz band\n", dev ); - return -EINVAL_ACTIVE_SCAN; - } - - if ( band == 0 ) { - /* This can happen for a 5GHz-only card with 5GHz - scanning masked out by an active request. */ - DBGC ( dev, "802.11 %p asked to prepare for scanning nothing\n", - dev ); - return -EINVAL_ACTIVE_SCAN; - } - - dev->nr_channels = 0; - - if ( active ) - net80211_add_channels ( dev, 1, 11, NET80211_REG_TXPOWER ); - else { - if ( band & NET80211_BAND_BIT_2GHZ ) - net80211_add_channels ( dev, 1, 14, - NET80211_REG_TXPOWER ); - if ( band & NET80211_BAND_BIT_5GHZ ) - net80211_add_channels ( dev, 36, 8, - NET80211_REG_TXPOWER ); - } - - net80211_filter_hw_channels ( dev ); - - /* Use channel 1 for now */ - dev->channel = 0; - dev->op->config ( dev, NET80211_CFG_CHANNEL ); - - /* Always do active probes at lowest (presumably first) speed */ - dev->rate = 0; - dev->nr_rates = 1; - dev->rates[0] = dev->hw->rates[dev->channels[0].band][0]; - dev->op->config ( dev, NET80211_CFG_RATE ); - - return 0; -} - -/** - * Prepare 802.11 device channel and rate set for communication - * - * @v dev 802.11 device - * @v wlan WLAN to prepare for communication with - * @ret rc Return status code - */ -int net80211_prepare_assoc ( struct net80211_device *dev, - struct net80211_wlan *wlan ) -{ - struct ieee80211_frame *hdr = wlan->beacon->data; - struct ieee80211_beacon *beacon = - ( struct ieee80211_beacon * ) hdr->data; - struct net80211_handshaker *handshaker; - int rc; - - assert ( dev->netdev->state & NETDEV_OPEN ); - - net80211_set_state ( dev, NET80211_ASSOCIATED, 0, 0 ); - memcpy ( dev->bssid, wlan->bssid, ETH_ALEN ); - strcpy ( dev->essid, wlan->essid ); - - free ( dev->rsn_ie ); - dev->rsn_ie = NULL; - - dev->last_beacon_timestamp = beacon->timestamp; - dev->tx_beacon_interval = 1024 * beacon->beacon_interval; - - /* Barring an IE that tells us the channel outright, assume - the channel we heard this AP best on is the channel it's - communicating on. */ - net80211_change_channel ( dev, wlan->channel ); - - rc = net80211_process_capab ( dev, beacon->capability ); - if ( rc ) - return rc; - - rc = net80211_process_ie ( dev, beacon->info_element, - wlan->beacon->tail ); - if ( rc ) - return rc; - - /* Associate at the lowest rate so we know it'll get through */ - dev->rate = 0; - dev->op->config ( dev, NET80211_CFG_RATE ); - - /* Free old handshaker and crypto, if they exist */ - if ( dev->handshaker && dev->handshaker->stop && - dev->handshaker->started ) - dev->handshaker->stop ( dev ); - free ( dev->handshaker ); - dev->handshaker = NULL; - free ( dev->crypto ); - free ( dev->gcrypto ); - dev->crypto = dev->gcrypto = NULL; - - /* Find new security handshaker to use */ - for_each_table_entry ( handshaker, NET80211_HANDSHAKERS ) { - if ( handshaker->protocol == wlan->handshaking ) { - dev->handshaker = zalloc ( sizeof ( *handshaker ) + - handshaker->priv_len ); - if ( ! dev->handshaker ) - return -ENOMEM; - - memcpy ( dev->handshaker, handshaker, - sizeof ( *handshaker ) ); - dev->handshaker->priv = ( ( void * ) dev->handshaker + - sizeof ( *handshaker ) ); - break; - } - } - - if ( ( wlan->handshaking != NET80211_SECPROT_NONE ) && - ! dev->handshaker ) { - DBGC ( dev, "802.11 %p no support for handshaking scheme %d\n", - dev, wlan->handshaking ); - return -( ENOTSUP | ( wlan->handshaking << 8 ) ); - } - - /* Initialize security handshaker */ - if ( dev->handshaker ) { - rc = dev->handshaker->init ( dev ); - if ( rc < 0 ) - return rc; - } - - return 0; -} - -/** - * Send 802.11 initial authentication frame - * - * @v dev 802.11 device - * @v wlan WLAN to authenticate with - * @v method Authentication method - * @ret rc Return status code - * - * @a method may be 0 for Open System authentication or 1 for Shared - * Key authentication. Open System provides no security in association - * whatsoever, relying on encryption for confidentiality, but Shared - * Key actively introduces security problems and is very rarely used. - */ -int net80211_send_auth ( struct net80211_device *dev, - struct net80211_wlan *wlan, int method ) -{ - struct io_buffer *iob = alloc_iob ( 64 ); - struct ieee80211_auth *auth; - - net80211_set_state ( dev, 0, NET80211_WAITING, 0 ); - iob_reserve ( iob, IEEE80211_TYP_FRAME_HEADER_LEN ); - auth = iob_put ( iob, sizeof ( *auth ) ); - auth->algorithm = method; - auth->tx_seq = 1; - auth->status = 0; - - return net80211_tx_mgmt ( dev, IEEE80211_STYPE_AUTH, wlan->bssid, iob ); -} - -/** - * Handle receipt of 802.11 authentication frame - * - * @v dev 802.11 device - * @v iob I/O buffer - * - * If the authentication method being used is Shared Key, and the - * frame that was received included challenge text, the frame is - * encrypted using the cryptosystem currently in effect and sent back - * to the AP to complete the authentication. - */ -static void net80211_handle_auth ( struct net80211_device *dev, - struct io_buffer *iob ) -{ - struct ieee80211_frame *hdr = iob->data; - struct ieee80211_auth *auth = - ( struct ieee80211_auth * ) hdr->data; - - if ( auth->tx_seq & 1 ) { - DBGC ( dev, "802.11 %p authentication received improperly " - "directed frame (seq. %d)\n", dev, auth->tx_seq ); - net80211_set_state ( dev, NET80211_WAITING, 0, - IEEE80211_STATUS_FAILURE ); - return; - } - - if ( auth->status != IEEE80211_STATUS_SUCCESS ) { - DBGC ( dev, "802.11 %p authentication failed: status %d\n", - dev, auth->status ); - net80211_set_state ( dev, NET80211_WAITING, 0, - auth->status ); - return; - } - - if ( auth->algorithm == IEEE80211_AUTH_SHARED_KEY && ! dev->crypto ) { - DBGC ( dev, "802.11 %p can't perform shared-key authentication " - "without a cryptosystem\n", dev ); - net80211_set_state ( dev, NET80211_WAITING, 0, - IEEE80211_STATUS_FAILURE ); - return; - } - - if ( auth->algorithm == IEEE80211_AUTH_SHARED_KEY && - auth->tx_seq == 2 ) { - /* Since the iob we got is going to be freed as soon - as we return, we can do some in-place - modification. */ - auth->tx_seq = 3; - auth->status = 0; - - memcpy ( hdr->addr2, hdr->addr1, ETH_ALEN ); - memcpy ( hdr->addr1, hdr->addr3, ETH_ALEN ); - - netdev_tx ( dev->netdev, - dev->crypto->encrypt ( dev->crypto, iob ) ); - return; - } - - net80211_set_state ( dev, NET80211_WAITING, NET80211_AUTHENTICATED, - IEEE80211_STATUS_SUCCESS ); - - return; -} - -/** - * Send 802.11 association frame - * - * @v dev 802.11 device - * @v wlan WLAN to associate with - * @ret rc Return status code - */ -int net80211_send_assoc ( struct net80211_device *dev, - struct net80211_wlan *wlan ) -{ - struct io_buffer *iob = alloc_iob ( 128 ); - struct ieee80211_assoc_req *assoc; - union ieee80211_ie *ie; - - net80211_set_state ( dev, 0, NET80211_WAITING, 0 ); - - iob_reserve ( iob, IEEE80211_TYP_FRAME_HEADER_LEN ); - assoc = iob->data; - - assoc->capability = IEEE80211_CAPAB_MANAGED; - if ( ! ( dev->hw->flags & NET80211_HW_NO_SHORT_PREAMBLE ) ) - assoc->capability |= IEEE80211_CAPAB_SHORT_PMBL; - if ( ! ( dev->hw->flags & NET80211_HW_NO_SHORT_SLOT ) ) - assoc->capability |= IEEE80211_CAPAB_SHORT_SLOT; - if ( wlan->crypto ) - assoc->capability |= IEEE80211_CAPAB_PRIVACY; - - assoc->listen_interval = 1; - - ie = net80211_marshal_request_info ( dev, assoc->info_element ); - - DBGP ( "802.11 %p about to send association request:\n", dev ); - DBGP_HD ( iob->data, ( void * ) ie - iob->data ); - - iob_put ( iob, ( void * ) ie - iob->data ); - - return net80211_tx_mgmt ( dev, IEEE80211_STYPE_ASSOC_REQ, - wlan->bssid, iob ); -} - -/** - * Handle receipt of 802.11 association reply frame - * - * @v dev 802.11 device - * @v iob I/O buffer - */ -static void net80211_handle_assoc_reply ( struct net80211_device *dev, - struct io_buffer *iob ) -{ - struct ieee80211_frame *hdr = iob->data; - struct ieee80211_assoc_resp *assoc = - ( struct ieee80211_assoc_resp * ) hdr->data; - - net80211_process_capab ( dev, assoc->capability ); - net80211_process_ie ( dev, assoc->info_element, iob->tail ); - - if ( assoc->status != IEEE80211_STATUS_SUCCESS ) { - DBGC ( dev, "802.11 %p association failed: status %d\n", - dev, assoc->status ); - net80211_set_state ( dev, NET80211_WAITING, 0, - assoc->status ); - return; - } - - /* ESSID was filled before the association request was sent */ - memcpy ( dev->bssid, hdr->addr3, ETH_ALEN ); - dev->aid = assoc->aid; - - net80211_set_state ( dev, NET80211_WAITING, NET80211_ASSOCIATED, - IEEE80211_STATUS_SUCCESS ); -} - - -/** - * Send 802.11 disassociation frame - * - * @v dev 802.11 device - * @v reason Reason for disassociation - * @v deauth If TRUE, send deauthentication instead of disassociation - * @ret rc Return status code - */ -static int net80211_send_disassoc ( struct net80211_device *dev, int reason, - int deauth ) -{ - struct io_buffer *iob = alloc_iob ( 64 ); - struct ieee80211_disassoc *disassoc; - - if ( ! ( dev->state & NET80211_ASSOCIATED ) ) - return -EINVAL; - - net80211_set_state ( dev, NET80211_ASSOCIATED, 0, 0 ); - iob_reserve ( iob, IEEE80211_TYP_FRAME_HEADER_LEN ); - disassoc = iob_put ( iob, sizeof ( *disassoc ) ); - disassoc->reason = reason; - - return net80211_tx_mgmt ( dev, deauth ? IEEE80211_STYPE_DEAUTH : - IEEE80211_STYPE_DISASSOC, dev->bssid, iob ); -} - - -/** - * Deauthenticate from current network and try again - * - * @v dev 802.11 device - * @v rc Return status code indicating reason - * - * The deauthentication will be sent using an 802.11 "unspecified - * reason", as is common, but @a rc will be set as a link-up - * error to aid the user in debugging. - */ -void net80211_deauthenticate ( struct net80211_device *dev, int rc ) -{ - net80211_send_disassoc ( dev, IEEE80211_REASON_UNSPECIFIED, 1 ); - dev->assoc_rc = rc; - netdev_link_err ( dev->netdev, rc ); - - net80211_autoassociate ( dev ); -} - - -/** Smoothing factor (1-7) for link quality calculation */ -#define LQ_SMOOTH 7 - -/** - * Update link quality information based on received beacon - * - * @v dev 802.11 device - * @v iob I/O buffer containing beacon - * @ret rc Return status code - */ -static void net80211_update_link_quality ( struct net80211_device *dev, - struct io_buffer *iob ) -{ - struct ieee80211_frame *hdr = iob->data; - struct ieee80211_beacon *beacon; - u32 dt, rxi; - - if ( ! ( dev->state & NET80211_ASSOCIATED ) ) - return; - - beacon = ( struct ieee80211_beacon * ) hdr->data; - dt = ( u32 ) ( beacon->timestamp - dev->last_beacon_timestamp ); - rxi = dev->rx_beacon_interval; - - rxi = ( LQ_SMOOTH * rxi ) + ( ( 8 - LQ_SMOOTH ) * dt ); - dev->rx_beacon_interval = rxi >> 3; - - dev->last_beacon_timestamp = beacon->timestamp; -} - - -/** - * Handle receipt of 802.11 management frame - * - * @v dev 802.11 device - * @v iob I/O buffer - * @v signal Signal strength of received frame - */ -static void net80211_handle_mgmt ( struct net80211_device *dev, - struct io_buffer *iob, int signal ) -{ - struct ieee80211_frame *hdr = iob->data; - struct ieee80211_disassoc *disassoc; - u16 stype = hdr->fc & IEEE80211_FC_SUBTYPE; - int keep = 0; - int is_deauth = ( stype == IEEE80211_STYPE_DEAUTH ); - - if ( ( hdr->fc & IEEE80211_FC_TYPE ) != IEEE80211_TYPE_MGMT ) { - free_iob ( iob ); - return; /* only handle management frames */ - } - - switch ( stype ) { - /* We reconnect on deauthentication and disassociation. */ - case IEEE80211_STYPE_DEAUTH: - case IEEE80211_STYPE_DISASSOC: - disassoc = ( struct ieee80211_disassoc * ) hdr->data; - net80211_set_state ( dev, is_deauth ? NET80211_AUTHENTICATED : - NET80211_ASSOCIATED, 0, - NET80211_IS_REASON | disassoc->reason ); - DBGC ( dev, "802.11 %p %s: reason %d\n", - dev, is_deauth ? "deauthenticated" : "disassociated", - disassoc->reason ); - - /* Try to reassociate, in case it's transient. */ - net80211_autoassociate ( dev ); - - break; - - /* We handle authentication and association. */ - case IEEE80211_STYPE_AUTH: - if ( ! ( dev->state & NET80211_AUTHENTICATED ) ) - net80211_handle_auth ( dev, iob ); - break; - - case IEEE80211_STYPE_ASSOC_RESP: - case IEEE80211_STYPE_REASSOC_RESP: - if ( ! ( dev->state & NET80211_ASSOCIATED ) ) - net80211_handle_assoc_reply ( dev, iob ); - break; - - /* We pass probes and beacons onto network scanning - code. Pass actions for future extensibility. */ - case IEEE80211_STYPE_BEACON: - net80211_update_link_quality ( dev, iob ); - /* fall through */ - case IEEE80211_STYPE_PROBE_RESP: - case IEEE80211_STYPE_ACTION: - if ( dev->keep_mgmt ) { - struct net80211_rx_info *rxinf; - rxinf = zalloc ( sizeof ( *rxinf ) ); - if ( ! rxinf ) { - DBGC ( dev, "802.11 %p out of memory\n", dev ); - break; - } - rxinf->signal = signal; - list_add_tail ( &iob->list, &dev->mgmt_queue ); - list_add_tail ( &rxinf->list, &dev->mgmt_info_queue ); - keep = 1; - } - break; - - case IEEE80211_STYPE_PROBE_REQ: - /* Some nodes send these broadcast. Ignore them. */ - break; - - case IEEE80211_STYPE_ASSOC_REQ: - case IEEE80211_STYPE_REASSOC_REQ: - /* We should never receive these, only send them. */ - DBGC ( dev, "802.11 %p received strange management request " - "(%04x)\n", dev, stype ); - break; - - default: - DBGC ( dev, "802.11 %p received unimplemented management " - "packet (%04x)\n", dev, stype ); - break; - } - - if ( ! keep ) - free_iob ( iob ); -} - -/* ---------- Packet handling functions ---------- */ - -/** - * Free buffers used by 802.11 fragment cache entry - * - * @v dev 802.11 device - * @v fcid Fragment cache entry index - * - * After this function, the referenced entry will be marked unused. - */ -static void net80211_free_frags ( struct net80211_device *dev, int fcid ) -{ - int j; - struct net80211_frag_cache *frag = &dev->frags[fcid]; - - for ( j = 0; j < 16; j++ ) { - if ( frag->iob[j] ) { - free_iob ( frag->iob[j] ); - frag->iob[j] = NULL; - } - } - - frag->seqnr = 0; - frag->start_ticks = 0; - frag->in_use = 0; -} - -/** - * Accumulate 802.11 fragments into one I/O buffer - * - * @v dev 802.11 device - * @v fcid Fragment cache entry index - * @v nfrags Number of fragments received - * @v size Sum of sizes of all fragments, including headers - * @ret iob I/O buffer containing reassembled packet - * - * This function does not free the fragment buffers. - */ -static struct io_buffer *net80211_accum_frags ( struct net80211_device *dev, - int fcid, int nfrags, int size ) -{ - struct net80211_frag_cache *frag = &dev->frags[fcid]; - int hdrsize = IEEE80211_TYP_FRAME_HEADER_LEN; - int nsize = size - hdrsize * ( nfrags - 1 ); - int i; - - struct io_buffer *niob = alloc_iob ( nsize ); - struct ieee80211_frame *hdr; - - /* Add the header from the first one... */ - memcpy ( iob_put ( niob, hdrsize ), frag->iob[0]->data, hdrsize ); - - /* ... and all the data from all of them. */ - for ( i = 0; i < nfrags; i++ ) { - int len = iob_len ( frag->iob[i] ) - hdrsize; - memcpy ( iob_put ( niob, len ), - frag->iob[i]->data + hdrsize, len ); - } - - /* Turn off the fragment bit. */ - hdr = niob->data; - hdr->fc &= ~IEEE80211_FC_MORE_FRAG; - - return niob; -} - -/** - * Handle receipt of 802.11 fragment - * - * @v dev 802.11 device - * @v iob I/O buffer containing fragment - * @v signal Signal strength with which fragment was received - */ -static void net80211_rx_frag ( struct net80211_device *dev, - struct io_buffer *iob, int signal ) -{ - struct ieee80211_frame *hdr = iob->data; - int fragnr = IEEE80211_FRAG ( hdr->seq ); - - if ( fragnr == 0 && ( hdr->fc & IEEE80211_FC_MORE_FRAG ) ) { - /* start a frag cache entry */ - int i, newest = -1; - u32 curr_ticks = currticks(), newest_ticks = 0; - u32 timeout = ticks_per_sec() * NET80211_FRAG_TIMEOUT; - - for ( i = 0; i < NET80211_NR_CONCURRENT_FRAGS; i++ ) { - if ( dev->frags[i].in_use == 0 ) - break; - - if ( dev->frags[i].start_ticks + timeout >= - curr_ticks ) { - net80211_free_frags ( dev, i ); - break; - } - - if ( dev->frags[i].start_ticks > newest_ticks ) { - newest = i; - newest_ticks = dev->frags[i].start_ticks; - } - } - - /* If we're being sent more concurrent fragmented - packets than we can handle, drop the newest so the - older ones have time to complete. */ - if ( i == NET80211_NR_CONCURRENT_FRAGS ) { - i = newest; - net80211_free_frags ( dev, i ); - } - - dev->frags[i].in_use = 1; - dev->frags[i].seqnr = IEEE80211_SEQNR ( hdr->seq ); - dev->frags[i].start_ticks = currticks(); - dev->frags[i].iob[0] = iob; - return; - } else { - int i; - for ( i = 0; i < NET80211_NR_CONCURRENT_FRAGS; i++ ) { - if ( dev->frags[i].in_use && dev->frags[i].seqnr == - IEEE80211_SEQNR ( hdr->seq ) ) - break; - } - if ( i == NET80211_NR_CONCURRENT_FRAGS ) { - /* Drop non-first not-in-cache fragments */ - DBGC ( dev, "802.11 %p dropped fragment fc=%04x " - "seq=%04x\n", dev, hdr->fc, hdr->seq ); - free_iob ( iob ); - return; - } - - dev->frags[i].iob[fragnr] = iob; - - if ( ! ( hdr->fc & IEEE80211_FC_MORE_FRAG ) ) { - int j, size = 0; - for ( j = 0; j < fragnr; j++ ) { - size += iob_len ( dev->frags[i].iob[j] ); - if ( dev->frags[i].iob[j] == NULL ) - break; - } - if ( j == fragnr ) { - /* We've got everything */ - struct io_buffer *niob = - net80211_accum_frags ( dev, i, fragnr, - size ); - net80211_free_frags ( dev, i ); - net80211_rx ( dev, niob, signal, 0 ); - } else { - DBGC ( dev, "802.11 %p dropping fragmented " - "packet due to out-of-order arrival, " - "fc=%04x seq=%04x\n", dev, hdr->fc, - hdr->seq ); - net80211_free_frags ( dev, i ); - } - } - } -} - -/** - * Handle receipt of 802.11 frame - * - * @v dev 802.11 device - * @v iob I/O buffer - * @v signal Received signal strength - * @v rate Bitrate at which frame was received, in 100 kbps units - * - * If the rate or signal is unknown, 0 should be passed. - */ -void net80211_rx ( struct net80211_device *dev, struct io_buffer *iob, - int signal, u16 rate ) -{ - struct ieee80211_frame *hdr = iob->data; - u16 type = hdr->fc & IEEE80211_FC_TYPE; - if ( ( hdr->fc & IEEE80211_FC_VERSION ) != IEEE80211_THIS_VERSION ) - goto drop; /* drop invalid-version packets */ - - if ( type == IEEE80211_TYPE_CTRL ) - goto drop; /* we don't handle control packets, - the hardware does */ - - if ( dev->last_rx_seq == hdr->seq ) - goto drop; /* avoid duplicate packet */ - dev->last_rx_seq = hdr->seq; - - if ( dev->hw->flags & NET80211_HW_RX_HAS_FCS ) { - /* discard the FCS */ - iob_unput ( iob, 4 ); - } - - /* Only decrypt packets from our BSSID, to avoid spurious errors */ - if ( ( hdr->fc & IEEE80211_FC_PROTECTED ) && - ! memcmp ( hdr->addr2, dev->bssid, ETH_ALEN ) ) { - /* Decrypt packet; record and drop if it fails */ - struct io_buffer *niob; - struct net80211_crypto *crypto = dev->crypto; - - if ( ! dev->crypto ) { - DBGC ( dev, "802.11 %p cannot decrypt packet " - "without a cryptosystem\n", dev ); - goto drop_crypt; - } - - if ( ( hdr->addr1[0] & 1 ) && dev->gcrypto ) { - /* Use group decryption if needed */ - crypto = dev->gcrypto; - } - - niob = crypto->decrypt ( crypto, iob ); - if ( ! niob ) { - DBGC ( dev, "802.11 %p decryption error\n", dev ); - goto drop_crypt; - } - free_iob ( iob ); - iob = niob; - } - - dev->last_signal = signal; - - /* Fragments go into the frag cache or get dropped. */ - if ( IEEE80211_FRAG ( hdr->seq ) != 0 - || ( hdr->fc & IEEE80211_FC_MORE_FRAG ) ) { - net80211_rx_frag ( dev, iob, signal ); - return; - } - - /* Management frames get handled, enqueued, or dropped. */ - if ( type == IEEE80211_TYPE_MGMT ) { - net80211_handle_mgmt ( dev, iob, signal ); - return; - } - - /* Data frames get dropped or sent to the net_device. */ - if ( ( hdr->fc & IEEE80211_FC_SUBTYPE ) != IEEE80211_STYPE_DATA ) - goto drop; /* drop QoS, CFP, or null data packets */ - - /* Update rate-control algorithm */ - if ( dev->rctl ) - rc80211_update_rx ( dev, hdr->fc & IEEE80211_FC_RETRY, rate ); - - /* Pass packet onward */ - if ( dev->state & NET80211_ASSOCIATED ) { - netdev_rx ( dev->netdev, iob ); - return; - } - - /* No association? Drop it. */ - goto drop; - - drop_crypt: - netdev_rx_err ( dev->netdev, NULL, EINVAL_CRYPTO_REQUEST ); - drop: - DBGC2 ( dev, "802.11 %p dropped packet fc=%04x seq=%04x\n", dev, - hdr->fc, hdr->seq ); - free_iob ( iob ); - return; -} - -/** Indicate an error in receiving a packet - * - * @v dev 802.11 device - * @v iob I/O buffer with received packet, or NULL - * @v rc Error code - * - * This logs the error with the wrapping net_device, and frees iob if - * it is passed. - */ -void net80211_rx_err ( struct net80211_device *dev, - struct io_buffer *iob, int rc ) -{ - netdev_rx_err ( dev->netdev, iob, rc ); -} - -/** Indicate the completed transmission of a packet - * - * @v dev 802.11 device - * @v iob I/O buffer of transmitted packet - * @v retries Number of times this packet was retransmitted - * @v rc Error code, or 0 for success - * - * This logs an error with the wrapping net_device if one occurred, - * and removes and frees the I/O buffer from its TX queue. The - * provided retry information is used to tune our transmission rate. - * - * If the packet did not need to be retransmitted because it was - * properly ACKed the first time, @a retries should be 0. - */ -void net80211_tx_complete ( struct net80211_device *dev, - struct io_buffer *iob, int retries, int rc ) -{ - /* Update rate-control algorithm */ - if ( dev->rctl ) - rc80211_update_tx ( dev, retries, rc ); - - /* Pass completion onward */ - netdev_tx_complete_err ( dev->netdev, iob, rc ); -} |