NOTE: this page is for archival only, see the note at the end of the page.

TableOfContents()

Most important issues

  • Make the stack SMP safe.
  • Add callbacks for devices with advanced firmware.
  • Changing WDS peer address doesn't add STA entry for new remote peer. [reported by Jouni Malinen]
  • Need to stop TX/RX when a radar is detected for the duration of scan for a new channel. (Partially solved by PRISM2_PARAM_RADIO_ENABLED.) [reported by Jouni Malinen]
  • Rate control algorithms should be applicable to individual devices separately (i. e. every device can have different algorithm). [suggested by Feyd] This will also solve Oops when removing of rate_control module and bringing an interface up afterwards. [reported by Larry Finger]

Other issues (in no particular order)

  • Easier handling of configuration requests (ieee80211_hw->config()). In the current implementation, driver has no way to find out which parameter is being set; setting all parameters on every call to config() is obviously not a good idea.

  • struct ieee80211_tx_queue_stats is strange (why not to use ieee80211_tx_queue_stats_data directly?)

  • Separate TX and RX antenna selection (ieee80211_conf->antenna_sel). [suggested by Ivo van Doorn]

  • Kicking DMA on the last fragment only (?) [suggested by Ivo van Doorn]

  • Call ieee80211_hw->config() after the card is initialized, so the driver is not forced to call it itself.

  • Put to the documentation a note that by setting the set_frag_threshold() handler the stack won't do fragmentation.
  • Why there is a beacon_update() handler? Maybe it would be easier for the driver to be allowed to call ieee80211_beacon_get() even in IBSS mode.
  • Add functions that will tell the driver which rates and modulations are allowed. Some cards need to tell their firmware about it.
  • Using of radiotap instead of Prism monitoring header.
  • Add dormant state support.
  • Add WLAN_CAPABILITY_QOS constant.
  • Move ETH_P_PAE from ieee80211_i.h to linux/if_ether.h.
  • Make IEEE80211_FRAGMENT_MAX configurable (preferably at run-time).
  • Embed ieee80211_key_conf into ieee80211_key so just one memcpy can be used in ieee80211_key_data2conf().
  • Alter LL_MAX_HEADER constant.
  • Fix the race in PS status update (see TODO in ieee80211_tx_status()).
  • get rid of all the embedded algorithms (AES, Michael, RC4, CRC) and use the crypto layer from the kernel [reported by Johannes Berg]
  • In ieee80211_ioctl_siwmode(), ieee80211_hw_config() is called twice.
  • split out frame crypto stuff into modules like in-kernel ieee80211 does [suggested by Johannes Berg]
  • Do not misuse iwpriv for generic ioctls (i.e. do not use iwpriv ioctls in the stack at all).
  • Remove ioctl (add_iface, WPA) and /proc compatibility stuff.
  • Move ieee80211_get_hdrlen* from ieee80211.c to ieee80211_proto.c.
  • Sort out function definitions in ieee80211_i.h (they are at two different places in the file now).
  • Review locking around passive scanning (ieee80211_rx_h_passive_scan).
  • Merge both types of scanning: software one (ieee80211_sta_scan_timer) and hardware/hostapd one (ieee80211_scan_handler).
  • Rework background scanning to work without background scan callback. [suggested by Johannes Berg]
  • Split ieee80211.c into several files.

  • ieee80211_rx_h_ieee80211_rx_h_ps_poll: do not pass rx->dev into hw->set_time. Pass mdev instead.

  • Make sure that a driver receive the same net_device every time (it's not now, e.g. for hw->config). Currently, random net_device is passed to a driver and ieee80211_dev_hw_data is expected to deal with this.

  • Add spin_lock_bh(&local->sub_if_lock) around accesses to local->sub_if_list.

  • ieee80211_if_conf should be a part of ieee80211_sub_if_data (similar to ieee80211_conf is a part of ieee80211_local).
  • In case of STA or IBSS, after a change of SSID or generic_element, ieee80211_if_conf should be called.
  • Calls to ieee80211_key_threshold_notify are needless in some places. When the interface is in STA mode, a lot of operations is performed and the result is thrown away.

  • "Strawman proposal for a generic frame format" (http://linux-net.osdl.org/index.php/Wireless:Txformat) [suggested by Solomon Peachy]

  • ieee80211_rx_michael_mic_report: comparing to IEEE80211_IF_TYPE_AP yields to false everytime. (FIXME: haven't it be fixed already?)
  • When WPA is on, iwconfig incorrectly reports "Encryption key:off". [reported by Alex Davis] (FIXME: haven't it be fixed already?)
  • Export information about softmac/fullmac type of the hardware to userspace. [suggested by Jouni Malinen]
  • Sometimes scanning is invoked even when the interface is down (e.g. IBSS and setting of SSID). [reported by Ivo van Doorn]
  • Investigate packet injection support for tools like aircrack. [suggested by Mark Wallis]
  • ieee80211_ioctl_remove_sta: sta_info_free should be called with locked = 0
  • Indentation in ieee80211_init().
  • Add get_wireless_stats to ieee80211_iw_handler_def. [suggested by Dan Williams]
  • Add software sequence numbering support.
  • Add RTS frame generation function.

  • Clean up headers mess (http://www.spinics.net/lists/netdev/msg12124.html). [suggested by Johannes Berg]

  • RCPI support (http://www.spinics.net/lists/netdev/msg12028.html) [suggested by Simon Barber]

  • generic_lock is unused. [reported by Jeff Garzik]

  • Get rid of bitfields (partially done, still left: ieee80211_txrx_data, ieee80211_tx_packet_data, ieee80211_tx_stored_packet, ieee80211_passive_scan, ieee80211_if_sta and ieee80211_sub_if_data). [suggested by Jeff Garzik]

  • ieee80211_regdom and ieee80211_japan_5ghz module paramaters should go away in favour of userspace regulatory app.

  • When STA in PS mode with queued frames is removed, hw TIM is not updated (i.e. hw->set_tim is not called). [reported by Johannes Berg]

  • #ifdef out wpa_test variable (but do not add #ifdefs into ifs).
  • Allow set_key to return -ENOBUFS to indicate there is no more room for keys and do sw encryption for this STA then. [suggested by Michael Buesch]

  • get rid of dropped data frame to not associated station 00:00:00:00:00:00 warnings wherever they come from (IPv6?)

Library functions we should add

  • PLCP Length calculation

Optimizations

  • ieee80211_get_hdrlen and ieee80211_is_eapol are called very often.
  • Inline ieee80211_get_bssid()?
  • All frames go through all of decryption functions. It should be possible to know what to expect and only pass it through those functions that are needed. [suggested by Johannes Berg]
  • Recognition of device incoming frame belongs to can be made much smarter and faster.
  • When one packet is dumped through several interfaces, some operations can be performed just once (e.g. searching for the key, sometimes decrypting, defragmentation etc.).
  • Add #ifdef's for not compiling AP stuff. [suggested by Jouni Malinen]
  • Move fragmentation etc. into 802.11 qdisc. [suggested by Simon Barber]
  • Try to switch from sw crypto to hw when there was no more room for STA keys in the hardware and one STA disassociates (so there is possibly a room now). [suggested by Johannes and Michael]
  • only allocate memory for sw keys, let driver/hw manage hw keys?
  • A lot of other stuff...

Coding style

  • Replace spaces by tabs (but not by one big patch, this should be done gradually while the code is modified).
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