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Diffstat (limited to 'gpxe/src/include/gpxe/net80211.h')
| -rw-r--r-- | gpxe/src/include/gpxe/net80211.h | 1186 |
1 files changed, 0 insertions, 1186 deletions
diff --git a/gpxe/src/include/gpxe/net80211.h b/gpxe/src/include/gpxe/net80211.h deleted file mode 100644 index 027e091c..00000000 --- a/gpxe/src/include/gpxe/net80211.h +++ /dev/null @@ -1,1186 +0,0 @@ -#ifndef _GPXE_NET80211_H -#define _GPXE_NET80211_H - -#include <gpxe/process.h> -#include <gpxe/ieee80211.h> -#include <gpxe/iobuf.h> -#include <gpxe/netdevice.h> -#include <gpxe/rc80211.h> - -/** @file - * - * The gPXE 802.11 MAC layer. - */ - -/* - * Major things NOT YET supported: - * - any type of security - * - 802.11n - * - * Major things that probably will NEVER be supported, barring a - * compelling use case and/or corporate sponsorship: - * - QoS - * - 802.1X authentication ("WPA Enterprise") - * - Contention-free periods - * - "ad-hoc" networks (IBSS), monitor mode, host AP mode - * - hidden networks on the 5GHz band due to regulatory issues - * - spectrum management on the 5GHz band (TPC and DFS), as required - * in some non-US regulatory domains - * - Clause 14 PHYs (Frequency-Hopping Spread Spectrum on 2.4GHz) - * and Clause 16 PHYs (infrared) - I'm not aware of any real-world - * use of these. - */ - -FILE_LICENCE ( GPL2_OR_LATER ); - -/* All 802.11 devices are handled using a generic "802.11 device" - net_device, with a link in its `priv' field to a net80211_device - which we use to handle 802.11-specific details. */ - - -/** @defgroup net80211_band RF bands on which an 802.11 device can transmit */ -/** @{ */ - -/** The 2.4 GHz ISM band, unlicensed in most countries */ -#define NET80211_BAND_2GHZ 0 -/** The band from 4.9 GHz to 5.7 GHz, which tends to be more restricted */ -#define NET80211_BAND_5GHZ 1 -/** Number of RF bands */ -#define NET80211_NR_BANDS 2 - -/** Bitmask for the 2GHz band */ -#define NET80211_BAND_BIT_2GHZ (1 << 0) -/** Bitmask for the 5GHz band */ -#define NET80211_BAND_BIT_5GHZ (1 << 1) - -/** @} */ - - -/** @defgroup net80211_mode 802.11 operation modes supported by hardware */ -/** @{ */ - -/** 802.11a: 54 Mbps operation using OFDM signaling on the 5GHz band */ -#define NET80211_MODE_A (1 << 0) - -/** 802.11b: 1-11 Mbps operation using DSSS/CCK signaling on the 2.4GHz band */ -#define NET80211_MODE_B (1 << 1) - -/** 802.11g: 54 Mbps operation using ERP/OFDM signaling on the 2.4GHz band */ -#define NET80211_MODE_G (1 << 2) - -/** 802.11n: High-rate operation using MIMO technology on 2.4GHz or 5GHz */ -#define NET80211_MODE_N (1 << 3) - -/** @} */ - - -/** @defgroup net80211_cfg Constants for the net80211 config callback */ -/** @{ */ - -/** Channel choice (@c dev->channel) or regulatory parameters have changed */ -#define NET80211_CFG_CHANNEL (1 << 0) - -/** Requested transmission rate (@c dev->rate) has changed */ -#define NET80211_CFG_RATE (1 << 1) - -/** Association has been established with a new BSS (@c dev->bssid) */ -#define NET80211_CFG_ASSOC (1 << 2) - -/** Low-level link parameters (short preamble, protection, etc) have changed */ -#define NET80211_CFG_PHY_PARAMS (1 << 3) - -/** @} */ - - -/** An 802.11 security handshaking protocol */ -enum net80211_security_proto { - /** No security handshaking - * - * This might be used with an open network or with WEP, as - * WEP does not have a cryptographic handshaking phase. - */ - NET80211_SECPROT_NONE = 0, - - /** Pre-shared key handshaking - * - * This implements the "WPA Personal" handshake. 802.1X - * authentication is not performed -- the user supplies a - * pre-shared key directly -- but there is a 4-way handshake - * between client and AP to verify that both have the same key - * without revealing the contents of that key. - */ - NET80211_SECPROT_PSK = 1, - - /** Full EAP 802.1X handshaking - * - * This implements the "WPA Enterprise" handshake, connecting - * to an 802.1X authentication server to provide credentials - * and receive a pairwise master key (PMK), which is then used - * in the same 4-way handshake as the PSK method. - */ - NET80211_SECPROT_EAP = 2, - - /** Dummy value used when the handshaking type can't be detected */ - NET80211_SECPROT_UNKNOWN = 3, -}; - - -/** An 802.11 data encryption algorithm */ -enum net80211_crypto_alg { - /** No security, an "Open" network */ - NET80211_CRYPT_NONE = 0, - - /** Network protected with WEP (awful RC4-based system) - * - * WEP uses a naive application of RC4, with a monotonically - * increasing initialization vector that is prepended to the - * key to initialize the RC4 keystream. It is highly insecure - * and can be completely cracked or subverted using automated, - * robust, freely available tools (aircrack-ng) in minutes. - * - * 40-bit and 104-bit WEP are differentiated only by the size - * of the key. They may be advertised as 64-bit and 128-bit, - * counting the non-random IV as part of the key bits. - */ - NET80211_CRYPT_WEP = 1, - - /** Network protected with TKIP (better RC4-based system) - * - * Usually known by its trade name of WPA (Wi-Fi Protected - * Access), TKIP implements a message integrity code (MIC) - * called Michael, a timestamp counter for replay prevention, - * and a key mixing function that together remove almost all - * the security problems with WEP. Countermeasures are - * implemented to prevent high data-rate attacks. - * - * There exists one known attack on TKIP, that allows one to - * send between 7 and 15 arbitrary short data packets on a - * QoS-enabled network given about an hour of data - * gathering. Since gPXE does not support QoS for 802.11 - * networks, this is not a threat to us. The only other method - * is a brute-force passphrase attack. - */ - NET80211_CRYPT_TKIP = 2, - - /** Network protected with CCMP (AES-based system) - * - * Often called WPA2 in commerce, or RSNA (Robust Security - * Network Architecture) in the 802.11 standard, CCMP is - * highly secure and does not have any known attack vectors. - * Since it is based on a block cipher, the statistical - * correlation and "chopchop" attacks used with great success - * against WEP and minor success against TKIP fail. - */ - NET80211_CRYPT_CCMP = 3, - - /** Dummy value used when the cryptosystem can't be detected */ - NET80211_CRYPT_UNKNOWN = 4, -}; - - -/** @defgroup net80211_state Bits for the 802.11 association state field */ -/** @{ */ - -/** An error code indicating the failure mode, or 0 if successful */ -#define NET80211_STATUS_MASK 0x7F - -/** Whether the error code provided is a "reason" code, not a "status" code */ -#define NET80211_IS_REASON 0x80 - -/** Whether we have found the network we will be associating with */ -#define NET80211_PROBED (1 << 8) - -/** Whether we have successfully authenticated with the network - * - * This usually has nothing to do with actual security; it is a - * holdover from older 802.11 implementation ideas. - */ -#define NET80211_AUTHENTICATED (1 << 9) - -/** Whether we have successfully associated with the network */ -#define NET80211_ASSOCIATED (1 << 10) - -/** Whether we have completed security handshaking with the network - * - * Once this is set, we can send data packets. For that reason this - * bit is set even in cases where no security handshaking is - * required. - */ -#define NET80211_CRYPTO_SYNCED (1 << 11) - -/** Whether the auto-association task is running */ -#define NET80211_WORKING (1 << 12) - -/** Whether the auto-association task is waiting for a reply from the AP */ -#define NET80211_WAITING (1 << 13) - -/** Whether the auto-association task should be suppressed - * - * This is set by the `iwlist' command so that it can open the device - * without starting another probe process that will interfere with its - * own. - */ -#define NET80211_NO_ASSOC (1 << 14) - -/** Whether this association was performed using a broadcast SSID - * - * If the user opened this device without netX/ssid set, the device's - * SSID will be set to that of the network it chooses to associate - * with, but the netX/ssid setting will remain blank. If we don't - * remember that we started from no specified SSID, it will appear - * every time settings are updated (e.g. after DHCP) that we need to - * reassociate due to the difference between the set SSID and our own. - */ -#define NET80211_AUTO_SSID (1 << 15) - - -/** @} */ - - -/** @defgroup net80211_phy 802.11 physical layer flags */ -/** @{ */ - -/** Whether to use RTS/CTS or CTS-to-self protection for transmissions - * - * Since the RTS or CTS is transmitted using 802.11b signaling, and - * includes a field indicating the amount of time that will be used by - * transmission of the following packet, this serves as an effective - * protection mechanism to avoid 802.11b clients interfering with - * 802.11g clients on mixed networks. - */ -#define NET80211_PHY_USE_PROTECTION (1 << 1) - -/** Whether to use 802.11b short preamble operation - * - * Short-preamble operation can moderately increase throughput on - * 802.11b networks operating between 2Mbps and 11Mbps. It is - * irrelevant for 802.11g data rates, since they use a different - * modulation scheme. - */ -#define NET80211_PHY_USE_SHORT_PREAMBLE (1 << 2) - -/** Whether to use 802.11g short slot operation - * - * This affects a low-level timing parameter of 802.11g transmissions. - */ -#define NET80211_PHY_USE_SHORT_SLOT (1 << 3) - -/** @} */ - - -/** The maximum number of TX rates we allow to be configured simultaneously */ -#define NET80211_MAX_RATES 16 - -/** The maximum number of channels we allow to be configured simultaneously */ -#define NET80211_MAX_CHANNELS 32 - -/** Seconds we'll wait to get all fragments of a packet */ -#define NET80211_FRAG_TIMEOUT 2 - -/** The number of fragments we can receive at once - * - * The 802.11 standard requires that this be at least 3. - */ -#define NET80211_NR_CONCURRENT_FRAGS 3 - -/** Maximum TX power to allow (dBm), if we don't get a regulatory hint */ -#define NET80211_REG_TXPOWER 20 - - -struct net80211_device; - -/** Operations that must be implemented by an 802.11 driver */ -struct net80211_device_operations { - /** Open 802.11 device - * - * @v dev 802.11 device - * @ret rc Return status code - * - * This method should allocate RX I/O buffers and enable the - * hardware to start transmitting and receiving packets on the - * channels its net80211_register() call indicated it could - * handle. It does not need to tune the antenna to receive - * packets on any particular channel. - */ - int ( * open ) ( struct net80211_device *dev ); - - /** Close 802.11 network device - * - * @v dev 802.11 device - * - * This method should stop the flow of packets, and call - * net80211_tx_complete() for any packets remaining in the - * device's TX queue. - */ - void ( * close ) ( struct net80211_device *dev ); - - /** Transmit packet on 802.11 network device - * - * @v dev 802.11 device - * @v iobuf I/O buffer - * @ret rc Return status code - * - * This method should cause the hardware to initiate - * transmission of the I/O buffer, using the channel and rate - * most recently indicated by an appropriate call to the - * @c config callback. The 802.11 layer guarantees that said - * channel and rate will be the same as those currently - * reflected in the fields of @a dev. - * - * If this method returns success, the I/O buffer remains - * owned by the network layer's TX queue, and the driver must - * eventually call net80211_tx_complete() to free the buffer - * whether transmission succeeded or not. If this method - * returns failure, it will be interpreted as "failure to - * enqueue buffer" and the I/O buffer will be immediately - * released. - * - * This method is guaranteed to be called only when the device - * is open. - */ - int ( * transmit ) ( struct net80211_device *dev, - struct io_buffer *iobuf ); - - /** Poll for completed and received packets - * - * @v dev 802.11 device - * - * This method should cause the hardware to check for - * completed transmissions and received packets. Any received - * packets should be delivered via net80211_rx(), and - * completed transmissions should be indicated using - * net80211_tx_complete(). - * - * This method is guaranteed to be called only when the device - * is open. - */ - void ( * poll ) ( struct net80211_device *dev ); - - /** Enable or disable interrupts - * - * @v dev 802.11 device - * @v enable If TRUE, interrupts should be enabled - */ - void ( * irq ) ( struct net80211_device *dev, int enable ); - - /** Update hardware state to match 802.11 layer state - * - * @v dev 802.11 device - * @v changed Set of flags indicating what may have changed - * @ret rc Return status code - * - * This method should cause the hardware state to be - * reinitialized from the state indicated in fields of - * net80211_device, in the areas indicated by bits set in - * @a changed. If the hardware is unable to do so, this method - * may return an appropriate error indication. - * - * This method is guaranteed to be called only when the device - * is open. - */ - int ( * config ) ( struct net80211_device *dev, int changed ); -}; - -/** An 802.11 RF channel. */ -struct net80211_channel -{ - /** The band with which this channel is associated */ - u8 band; - - /** A channel number interpreted according to the band - * - * The 2.4GHz band uses channel numbers from 1-13 at 5MHz - * intervals such that channel 1 is 2407 MHz; channel 14, - * legal for use only in Japan, is defined separately as 2484 - * MHz. Adjacent channels will overlap, since 802.11 - * transmissions use a 20 MHz (4-channel) bandwidth. Most - * commonly, channels 1, 6, and 11 are used. - * - * The 5GHz band uses channel numbers derived directly from - * the frequency; channel 0 is 5000 MHz, and channels are - * always spaced 5 MHz apart. Channel numbers over 180 are - * relative to 4GHz instead of 5GHz, but these are rarely - * seen. Most channels are not legal for use. - */ - u8 channel_nr; - - /** The center frequency for this channel - * - * Currently a bandwidth of 20 MHz is assumed. - */ - u16 center_freq; - - /** Hardware channel value */ - u16 hw_value; - - /** Maximum allowable transmit power, in dBm - * - * This should be interpreted as EIRP, the power supplied to - * an ideal isotropic antenna in order to achieve the same - * average signal intensity as the real hardware at a - * particular distance. - * - * Currently no provision is made for directional antennas. - */ - u8 maxpower; -}; - -/** Information on the capabilities of an 802.11 hardware device - * - * In its probe callback, an 802.11 driver must read hardware - * registers to determine the appropriate contents of this structure, - * fill it, and pass it to net80211_register() so that the 802.11 - * layer knows how to treat the hardware and what to advertise as - * supported to access points. - */ -struct net80211_hw_info -{ - /** Default hardware MAC address. - * - * The user may change this by setting the @c netX/mac setting - * before the driver's open function is called; in that case - * the driver must set the hardware MAC address to the address - * contained in the wrapping net_device's ll_addr field, or if - * that is impossible, set that ll_addr field back to the - * unchangeable hardware MAC address. - */ - u8 hwaddr[ETH_ALEN]; - - /** A bitwise OR of the 802.11x modes supported by this device */ - int modes; - - /** A bitwise OR of the bands on which this device can communicate */ - int bands; - - /** A set of flags indicating peculiarities of this device. */ - enum { - /** Received frames include a frame check sequence. */ - NET80211_HW_RX_HAS_FCS = (1 << 1), - - /** Hardware doesn't support 2.4GHz short preambles - * - * This is only relevant for 802.11b operation above - * 2Mbps. All 802.11g devices support short preambles. - */ - NET80211_HW_NO_SHORT_PREAMBLE = (1 << 2), - - /** Hardware doesn't support 802.11g short slot operation */ - NET80211_HW_NO_SHORT_SLOT = (1 << 3), - } flags; - - /** Signal strength information that can be provided by the device - * - * Signal strength is passed to net80211_rx(), primarily to - * allow determination of the closest access point for a - * multi-AP network. The units are provided for completeness - * of status displays. - */ - enum { - /** No signal strength information supported */ - NET80211_SIGNAL_NONE = 0, - /** Signal strength in arbitrary units */ - NET80211_SIGNAL_ARBITRARY, - /** Signal strength in decibels relative to arbitrary base */ - NET80211_SIGNAL_DB, - /** Signal strength in decibels relative to 1mW */ - NET80211_SIGNAL_DBM, - } signal_type; - - /** Maximum signal in arbitrary cases - * - * If signal_type is NET80211_SIGNAL_ARBITRARY or - * NET80211_SIGNAL_DB, the driver should report it on a scale - * from 0 to signal_max. - */ - unsigned signal_max; - - /** List of RF channels supported by the card */ - struct net80211_channel channels[NET80211_MAX_CHANNELS]; - - /** Number of supported channels */ - int nr_channels; - - /** List of transmission rates supported by the card, indexed by band - * - * Rates should be in 100kbps increments (e.g. 11 Mbps would - * be represented as the number 110). - */ - u16 rates[NET80211_NR_BANDS][NET80211_MAX_RATES]; - - /** Number of supported rates, indexed by band */ - int nr_rates[NET80211_NR_BANDS]; - - /** Estimate of the time required to change channels, in microseconds - * - * If this is not known, a guess on the order of a few - * milliseconds (value of 1000-5000) is reasonable. - */ - unsigned channel_change_time; -}; - -/** Structure tracking received fragments for a packet - * - * We set up a fragment cache entry when we receive a packet marked as - * fragment 0 with the "more fragments" bit set in its frame control - * header. We are required by the 802.11 standard to track 3 - * fragmented packets arriving simultaneously; if we receive more we - * may drop some. Upon receipt of a new fragment-0 packet, if no entry - * is available or expired, we take over the most @e recent entry for - * the new packet, since we don't want to starve old entries from ever - * finishing at all. If we get a fragment after the zeroth with no - * cache entry for its packet, we drop it. - */ -struct net80211_frag_cache -{ - /** Whether this cache entry is in use */ - u8 in_use; - - /** Sequence number of this MSDU (packet) */ - u16 seqnr; - - /** Timestamp from point at which first fragment was collected */ - u32 start_ticks; - - /** Buffers for each fragment */ - struct io_buffer *iob[16]; -}; - - -/** Interface to an 802.11 security handshaking protocol - * - * Security handshaking protocols handle parsing a user-specified key - * into a suitable input to the encryption algorithm, and for WPA and - * better systems, manage performing whatever authentication with the - * network is necessary. - * - * At all times when any method in this structure is called with a - * net80211_device argument @a dev, a dynamically allocated copy of - * the handshaker structure itself with space for the requested amount - * of private data may be accessed as @c dev->handshaker. The - * structure will not be modified, and will only be freed during - * reassociation and device closing after the @a stop method has been - * called. - */ -struct net80211_handshaker -{ - /** The security handshaking protocol implemented */ - enum net80211_security_proto protocol; - - /** Initialize security handshaking protocol - * - * @v dev 802.11 device - * @ret rc Return status code - * - * This method is expected to access @c netX/key or other - * applicable settings to determine the parameters for - * handshaking. If no handshaking is required, it should call - * sec80211_install() with the cryptosystem and key that are - * to be used, and @c start and @c step should be set to @c - * NULL. - * - * This is always called just before association is performed, - * but after its parameters have been set; in particular, you - * may rely on the contents of the @a essid field in @a dev. - */ - int ( * init ) ( struct net80211_device *dev ); - - /** Start handshaking - * - * @v dev 802.11 device - * @ret rc Return status code - * - * This method is expected to set up internal state so that - * packets sent immediately after association, before @a step - * can be called, will be handled appropriately. - * - * This is always called just before association is attempted. - */ - int ( * start ) ( struct net80211_device *dev ); - - /** Process handshaking state - * - * @v dev 802.11 device - * @ret rc Return status code, or positive if done - * - * This method is expected to perform as much progress on the - * protocol it implements as is possible without blocking. It - * should return 0 if it wishes to be called again, a negative - * return status code on error, or a positive value if - * handshaking is complete. In the case of a positive return, - * net80211_crypto_install() must have been called. - * - * If handshaking may require further action (e.g. an AP that - * might decide to rekey), handlers must be installed by this - * function that will act without further calls to @a step. - */ - int ( * step ) ( struct net80211_device *dev ); - - /** Change cryptographic key based on setting - * - * @v dev 802.11 device - * @ret rc Return status code - * - * This method is called whenever the @c netX/key setting - * @e may have been changed. It is expected to determine - * whether it did in fact change, and if so, to install the - * new key using net80211_crypto_install(). If it is not - * possible to do this immediately, this method should return - * an error; in that case the 802.11 stack will reassociate, - * following the usual init/start/step sequence. - * - * This method is only relevant when it is possible to - * associate successfully with an incorrect key. When it is - * not, a failed association will be retried until the user - * changes the key setting, and a successful association will - * not be dropped due to such a change. When association with - * an incorrect key is impossible, this function should return - * 0 after performing no action. - */ - int ( * change_key ) ( struct net80211_device *dev ); - - /** Stop security handshaking handlers - * - * @v dev 802.11 device - * - * This method is called just before freeing a security - * handshaker; it could, for example, delete a process that @a - * start had created to manage the security of the connection. - * If not needed it may be set to NULL. - */ - void ( * stop ) ( struct net80211_device *dev ); - - /** Amount of private data requested - * - * Before @c init is called for the first time, this structure's - * @c priv pointer will point to this many bytes of allocated - * data, where the allocation will be performed separately for - * each net80211_device. - */ - int priv_len; - - /** Whether @a start has been called - * - * Reset to 0 after @a stop is called. - */ - int started; - - /** Pointer to private data - * - * In initializing this structure statically for a linker - * table, set this to NULL. - */ - void *priv; -}; - -#define NET80211_HANDSHAKERS __table ( struct net80211_handshaker, \ - "net80211_handshakers" ) -#define __net80211_handshaker __table_entry ( NET80211_HANDSHAKERS, 01 ) - - -/** Interface to an 802.11 cryptosystem - * - * Cryptosystems define a net80211_crypto structure statically, using - * a gPXE linker table to make it available to the 802.11 layer. When - * the cryptosystem needs to be used, the 802.11 code will allocate a - * copy of the static definition plus whatever space the algorithm has - * requested for private state, and point net80211_device::crypto or - * net80211_device::gcrypto at it. - */ -struct net80211_crypto -{ - /** The cryptographic algorithm implemented */ - enum net80211_crypto_alg algorithm; - - /** Initialize cryptosystem using a given key - * - * @v crypto 802.11 cryptosystem - * @v key Pointer to key bytes - * @v keylen Number of key bytes - * @v rsc Initial receive sequence counter, if applicable - * @ret rc Return status code - * - * This method is passed the communication key provided by the - * security handshake handler, which will already be in the - * low-level form required. It may not store a pointer to the - * key after returning; it must copy it to its private storage. - */ - int ( * init ) ( struct net80211_crypto *crypto, const void *key, - int keylen, const void *rsc ); - - /** Encrypt a frame using the cryptosystem - * - * @v crypto 802.11 cryptosystem - * @v iob I/O buffer - * @ret eiob Newly allocated I/O buffer with encrypted packet - * - * This method is called to encrypt a single frame. It is - * guaranteed that initialize() will have completed - * successfully before this method is called. - * - * The frame passed already has an 802.11 header prepended, - * but the PROTECTED bit in the frame control field will not - * be set; this method is responsible for setting it. The - * returned I/O buffer should contain a complete copy of @a - * iob, including the 802.11 header, but with the PROTECTED - * bit set, the data encrypted, and whatever encryption - * headers/trailers are necessary added. - * - * This method should never free the passed I/O buffer. - * - * Return NULL if the packet could not be encrypted, due to - * memory limitations or otherwise. - */ - struct io_buffer * ( * encrypt ) ( struct net80211_crypto *crypto, - struct io_buffer *iob ); - - /** Decrypt a frame using the cryptosystem - * - * @v crypto 802.11 cryptosystem - * @v eiob Encrypted I/O buffer - * @ret iob Newly allocated I/O buffer with decrypted packet - * - * This method is called to decrypt a single frame. It is - * guaranteed that initialize() will have completed - * successfully before this method is called. - * - * Decryption follows the reverse of the pattern used for - * encryption: this method must copy the 802.11 header into - * the returned packet, decrypt the data stream, remove any - * encryption header or trailer, and clear the PROTECTED bit - * in the frame control header. - * - * This method should never free the passed I/O buffer. - * - * Return NULL if memory was not available for decryption, if - * a consistency or integrity check on the decrypted frame - * failed, or if the decrypted frame should not be processed - * by the network stack for any other reason. - */ - struct io_buffer * ( * decrypt ) ( struct net80211_crypto *crypto, - struct io_buffer *iob ); - - /** Length of private data requested to be allocated */ - int priv_len; - - /** Private data for the algorithm to store key and state info */ - void *priv; -}; - -#define NET80211_CRYPTOS __table ( struct net80211_crypto, "net80211_cryptos" ) -#define __net80211_crypto __table_entry ( NET80211_CRYPTOS, 01 ) - - -struct net80211_probe_ctx; -struct net80211_assoc_ctx; - - -/** Structure encapsulating the complete state of an 802.11 device - * - * An 802.11 device is always wrapped by a network device, and this - * network device is always pointed to by the @a netdev field. In - * general, operations should never be performed by 802.11 code using - * netdev functions directly. It is usually the case that the 802.11 - * layer might need to do some processing or bookkeeping on top of - * what the netdevice code will do. - */ -struct net80211_device -{ - /** The net_device that wraps us. */ - struct net_device *netdev; - - /** List of 802.11 devices. */ - struct list_head list; - - /** 802.11 device operations */ - struct net80211_device_operations *op; - - /** Driver private data */ - void *priv; - - /** Information about the hardware, provided to net80211_register() */ - struct net80211_hw_info *hw; - - /* ---------- Channel and rate fields ---------- */ - - /** A list of all possible channels we might use */ - struct net80211_channel channels[NET80211_MAX_CHANNELS]; - - /** The number of channels in the channels array */ - u8 nr_channels; - - /** The channel currently in use, as an index into the channels array */ - u8 channel; - - /** A list of all possible TX rates we might use - * - * Rates are in units of 100 kbps. - */ - u16 rates[NET80211_MAX_RATES]; - - /** The number of transmission rates in the rates array */ - u8 nr_rates; - - /** The rate currently in use, as an index into the rates array */ - u8 rate; - - /** The rate to use for RTS/CTS transmissions - * - * This is always the fastest basic rate that is not faster - * than the data rate in use. Also an index into the rates array. - */ - u8 rtscts_rate; - - /** Bitmask of basic rates - * - * If bit N is set in this value, with the LSB considered to - * be bit 0, then rate N in the rates array is a "basic" rate. - * - * We don't decide which rates are "basic"; our AP does, and - * we respect its wishes. We need to be able to identify basic - * rates in order to calculate the duration of a CTS packet - * used for 802.11 g/b interoperability. - */ - u32 basic_rates; - - /* ---------- Association fields ---------- */ - - /** The asynchronous association process. - * - * When an 802.11 netdev is opened, or when the user changes - * the SSID setting on an open 802.11 device, an - * autoassociation task is started by net80211_autoassocate() - * to associate with the new best network. The association is - * asynchronous, but no packets can be transmitted until it is - * complete. If it is successful, the wrapping net_device is - * set as "link up". If it fails, @c assoc_rc will be set with - * an error indication. - */ - struct process proc_assoc; - - /** Network with which we are associating - * - * This will be NULL when we are not actively in the process - * of associating with a network we have already successfully - * probed for. - */ - struct net80211_wlan *associating; - - /** Context for the association process - * - * This is a probe_ctx if the @c PROBED flag is not set in @c - * state, and an assoc_ctx otherwise. - */ - union { - struct net80211_probe_ctx *probe; - struct net80211_assoc_ctx *assoc; - } ctx; - - /** Security handshaker being used */ - struct net80211_handshaker *handshaker; - - /** State of our association to the network - * - * Since the association process happens asynchronously, it's - * necessary to have some channel of communication so the - * driver can say "I got an association reply and we're OK" or - * similar. This variable provides that link. It is a bitmask - * of any of NET80211_PROBED, NET80211_AUTHENTICATED, - * NET80211_ASSOCIATED, NET80211_CRYPTO_SYNCED to indicate how - * far along in associating we are; NET80211_WORKING if the - * association task is running; and NET80211_WAITING if a - * packet has been sent that we're waiting for a reply to. We - * can only be crypto-synced if we're associated, we can - * only be associated if we're authenticated, we can only be - * authenticated if we've probed. - * - * If an association process fails (that is, we receive a - * packet with an error indication), the error code is copied - * into bits 6-0 of this variable and bit 7 is set to specify - * what type of error code it is. An AP can provide either a - * "status code" (0-51 are defined) explaining why it refused - * an association immediately, or a "reason code" (0-45 are - * defined) explaining why it canceled an association after it - * had originally OK'ed it. Status and reason codes serve - * similar functions, but they use separate error message - * tables. A gPXE-formatted return status code (negative) is - * placed in @c assoc_rc. - * - * If the failure to associate is indicated by a status code, - * the NET80211_IS_REASON bit will be clear; if it is - * indicated by a reason code, the bit will be set. If we were - * successful, both zero status and zero reason mean success, - * so there is no ambiguity. - * - * To prevent association when opening the device, user code - * can set the NET80211_NO_ASSOC bit. The final bit in this - * variable, NET80211_AUTO_SSID, is used to remember whether - * we picked our SSID through automated probing as opposed to - * user specification; the distinction becomes relevant in the - * settings applicator. - */ - u16 state; - - /** Return status code associated with @c state */ - int assoc_rc; - - /** RSN or WPA information element to include with association - * - * If set to @c NULL, none will be included. It is expected - * that this will be set by the @a init function of a security - * handshaker if it is needed. - */ - union ieee80211_ie *rsn_ie; - - /* ---------- Parameters of currently associated network ---------- */ - - /** 802.11 cryptosystem for our current network - * - * For an open network, this will be set to NULL. - */ - struct net80211_crypto *crypto; - - /** 802.11 cryptosystem for multicast and broadcast frames - * - * If this is NULL, the cryptosystem used for receiving - * unicast frames will also be used for receiving multicast - * and broadcast frames. Transmitted multicast and broadcast - * frames are always sent unicast to the AP, who multicasts - * them on our behalf; thus they always use the unicast - * cryptosystem. - */ - struct net80211_crypto *gcrypto; - - /** MAC address of the access point most recently associated */ - u8 bssid[ETH_ALEN]; - - /** SSID of the access point we are or will be associated with - * - * Although the SSID field in 802.11 packets is generally not - * NUL-terminated, here and in net80211_wlan we add a NUL for - * convenience. - */ - char essid[IEEE80211_MAX_SSID_LEN+1]; - - /** Association ID given to us by the AP */ - u16 aid; - - /** TSFT value for last beacon received, microseconds */ - u64 last_beacon_timestamp; - - /** Time between AP sending beacons, microseconds */ - u32 tx_beacon_interval; - - /** Smoothed average time between beacons, microseconds */ - u32 rx_beacon_interval; - - /* ---------- Physical layer information ---------- */ - - /** Physical layer options - * - * These control the use of CTS protection, short preambles, - * and short-slot operation. - */ - int phy_flags; - - /** Signal strength of last received packet */ - int last_signal; - - /** Rate control state */ - struct rc80211_ctx *rctl; - - /* ---------- Packet handling state ---------- */ - - /** Fragment reassembly state */ - struct net80211_frag_cache frags[NET80211_NR_CONCURRENT_FRAGS]; - - /** The sequence number of the last packet we sent */ - u16 last_tx_seqnr; - - /** Packet duplication elimination state - * - * We are only required to handle immediate duplicates for - * each direct sender, and since we can only have one direct - * sender (the AP), we need only keep the sequence control - * field from the most recent packet we've received. Thus, - * this field stores the last sequence control field we've - * received for a packet from the AP. - */ - u16 last_rx_seq; - - /** RX management packet queue - * - * Sometimes we want to keep probe, beacon, and action packets - * that we receive, such as when we're scanning for networks. - * Ordinarily we drop them because they are sent at a large - * volume (ten beacons per second per AP, broadcast) and we - * have no need of them except when we're scanning. - * - * When keep_mgmt is TRUE, received probe, beacon, and action - * management packets will be stored in this queue. - */ - struct list_head mgmt_queue; - - /** RX management packet info queue - * - * We need to keep track of the signal strength for management - * packets we're keeping, because that provides the only way - * to distinguish between multiple APs for the same network. - * Since we can't extend io_buffer to store signal, this field - * heads a linked list of "RX packet info" structures that - * contain that signal strength field. Its entries always - * parallel the entries in mgmt_queue, because the two queues - * are always added to or removed from in parallel. - */ - struct list_head mgmt_info_queue; - - /** Whether to store management packets - * - * Received beacon, probe, and action packets will be added to - * mgmt_queue (and their signal strengths added to - * mgmt_info_queue) only when this variable is TRUE. It should - * be set by net80211_keep_mgmt() (which returns the old - * value) only when calling code is prepared to poll the - * management queue frequently, because packets will otherwise - * pile up and exhaust memory. - */ - int keep_mgmt; -}; - -/** Structure representing a probed network. - * - * This is returned from the net80211_probe_finish functions and - * passed to the low-level association functions. At least essid, - * bssid, channel, beacon, and security must be filled in if you want - * to build this structure manually. - */ -struct net80211_wlan -{ - /** The human-readable ESSID (network name) - * - * Although the 802.11 SSID field is generally not - * NUL-terminated, the gPXE code adds an extra NUL (and - * expects one in this structure) for convenience. - */ - char essid[IEEE80211_MAX_SSID_LEN+1]; - - /** MAC address of the strongest-signal access point for this ESSID */ - u8 bssid[ETH_ALEN]; - - /** Signal strength of beacon frame from that access point */ - int signal; - - /** The channel on which that access point communicates - * - * This is a raw channel number (net80211_channel::channel_nr), - * so that it will not be affected by reconfiguration of the - * device channels array. - */ - int channel; - - /** The complete beacon or probe-response frame received */ - struct io_buffer *beacon; - - /** Security handshaking method used on the network */ - enum net80211_security_proto handshaking; - - /** Cryptographic algorithm used on the network */ - enum net80211_crypto_alg crypto; - - /** Link to allow chaining multiple structures into a list to - be returned from net80211_probe_finish_all(). */ - struct list_head list; -}; - - -/** 802.11 encryption key setting */ -extern struct setting net80211_key_setting __setting; - - -/** - * @defgroup net80211_probe 802.11 network location API - * @{ - */ -int net80211_prepare_probe ( struct net80211_device *dev, int band, - int active ); -struct net80211_probe_ctx * net80211_probe_start ( struct net80211_device *dev, - const char *essid, - int active ); -int net80211_probe_step ( struct net80211_probe_ctx *ctx ); -struct net80211_wlan * -net80211_probe_finish_best ( struct net80211_probe_ctx *ctx ); -struct list_head *net80211_probe_finish_all ( struct net80211_probe_ctx *ctx ); - -void net80211_free_wlan ( struct net80211_wlan *wlan ); -void net80211_free_wlanlist ( struct list_head *list ); -/** @} */ - - -/** - * @defgroup net80211_mgmt 802.11 network management API - * @{ - */ -struct net80211_device * net80211_get ( struct net_device *netdev ); -void net80211_autoassociate ( struct net80211_device *dev ); - -int net80211_change_channel ( struct net80211_device *dev, int channel ); -void net80211_set_rate_idx ( struct net80211_device *dev, int rate ); - -int net80211_keep_mgmt ( struct net80211_device *dev, int enable ); -struct io_buffer * net80211_mgmt_dequeue ( struct net80211_device *dev, - int *signal ); -int net80211_tx_mgmt ( struct net80211_device *dev, u16 fc, - u8 bssid[ETH_ALEN], struct io_buffer *iob ); -/** @} */ - - -/** - * @defgroup net80211_assoc 802.11 network association API - * @{ - */ -int net80211_prepare_assoc ( struct net80211_device *dev, - struct net80211_wlan *wlan ); -int net80211_send_auth ( struct net80211_device *dev, - struct net80211_wlan *wlan, int method ); -int net80211_send_assoc ( struct net80211_device *dev, - struct net80211_wlan *wlan ); -void net80211_deauthenticate ( struct net80211_device *dev, int rc ); -/** @} */ - - -/** - * @defgroup net80211_driver 802.11 driver interface API - * @{ - */ -struct net80211_device *net80211_alloc ( size_t priv_size ); -int net80211_register ( struct net80211_device *dev, - struct net80211_device_operations *ops, - struct net80211_hw_info *hw ); -u16 net80211_duration ( struct net80211_device *dev, int bytes, u16 rate ); -void net80211_rx ( struct net80211_device *dev, struct io_buffer *iob, - int signal, u16 rate ); -void net80211_rx_err ( struct net80211_device *dev, - struct io_buffer *iob, int rc ); -void net80211_tx_complete ( struct net80211_device *dev, - struct io_buffer *iob, int retries, int rc ); -void net80211_unregister ( struct net80211_device *dev ); -void net80211_free ( struct net80211_device *dev ); -/** @} */ - -/** - * Calculate duration field for a CTS control frame - * - * @v dev 802.11 device - * @v size Size of the packet being cleared to send - * - * A CTS control frame's duration field captures the frame being - * protected and its 10-byte ACK. - */ -static inline u16 net80211_cts_duration ( struct net80211_device *dev, - int size ) -{ - return ( net80211_duration ( dev, 10, - dev->rates[dev->rtscts_rate] ) + - net80211_duration ( dev, size, dev->rates[dev->rate] ) ); -} - -#endif |