kernel/linux.git/net/wireless/mesh.c, branch v6.6.131

wifi: cfg80211: do some rework towards MLO link APIs

2022-06-20T10:54:58+00:00

In order to support multi-link operation with multiple links, start adding some APIs. The notable addition here is to have the link ID in a new nl80211 attribute, that will be used to differentiate the links in many nl80211 operations. So far, this patch adds the netlink NL80211_ATTR_MLO_LINK_ID attribute (as well as the NL80211_ATTR_MLO_LINKS attribute) and plugs it through the system in some places, checking the validity etc. along with other infrastructure needed for it. For now, I've decided to include only the over-the-air link ID in the API. I know we discussed that we eventually need to have to have other ways of identifying a link, but for local AP mode and auth/assoc commands as well as set_key etc. we'll use the OTA ID. Also included in this patch is some refactoring of the data structures in struct wireless_dev, splitting for the first time the data into type dependent pieces, to make reasoning about these things easier. Signed-off-by: Johannes Berg

cfg80211/mac80211: add mesh_param "mesh_nolearn" to skip path discovery

2020-07-31T07:24:23+00:00

Currently, before being able to forward a packet between two 802.11s nodes, both a PLINK handshake is performed upon receiving a beacon and then later a PREQ/PREP exchange for path discovery is performed on demand upon receiving a data frame to forward. When running a mesh protocol on top of an 802.11s interface, like batman-adv, we do not need the multi-hop mesh routing capabilities of 802.11s and usually set mesh_fwding=0. However, even with mesh_fwding=0 the PREQ/PREP path discovery is still performed on demand. Even though in this scenario the next hop PREQ/PREP will determine is always the direct 11s neighbor node. The new mesh_nolearn parameter allows to skip the PREQ/PREP exchange in this scenario, leading to a reduced delay, reduced packet buffering and simplifies HWMP in general. mesh_nolearn is still rather conservative in that if the packet destination is not a direct 11s neighbor, it will fall back to PREQ/PREP path discovery. For normal, multi-hop 802.11s mesh routing it is usually not advisable to enable mesh_nolearn as a transmission to a direct but distant neighbor might be worse than reaching that same node via a more robust / higher throughput etc. multi-hop path. Cc: Sven Eckelmann Cc: Simon Wunderlich Signed-off-by: Linus Lüssing Link: https://lore.kernel.org/r/20200617073034.26149-1-linus.luessing@c0d3.blue [fix nl80211 policy to range 0/1 only] Signed-off-by: Johannes Berg

nl80211: Add SOCKET_OWNER support to JOIN_MESH

2018-03-29T08:38:24+00:00

Signed-off-by: Denis Kenzior [johannes: fix race with wdev lock/unlock by just acquiring once] Signed-off-by: Johannes Berg

cfg80211: use only 1Mbps for basic rates in mesh

2018-01-31T11:38:56+00:00

Mesh used to use the mandatory rates as basic rates, but we got the calculation of mandatory rates wrong until some time ago. Fix this this broke interoperability with older versions since now more basic rates are required, and thus the MBSS isn't the same and the network stops working. Fix this by simply using only 1Mbps as the basic rate in 2.4GHz. Since the changed mandatory rates only affected 2.4GHz, this is all we need to make it work again. Reported-and-tested-by: Matthias Schiffer Fixes: 1bd773c077de ("wireless: set correct mandatory rate flags") Signed-off-by: Johannes Berg

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55+00:00

Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

wireless: Only join DFS channels in mesh mode if userspace flags support

2017-05-19T11:25:58+00:00

When joining a mesh network it is not guaranteed that userspace has a daemon listening for radar events. This is however required for channels requiring DFS. To flag that userspace will handle radar events, it needs to set NL80211_ATTR_HANDLE_DFS. This matches the current mechanism used for IBSS mode. Signed-off-by: Benjamin Berg Signed-off-by: Simon Wunderlich Signed-off-by: Johannes Berg

cfg80211: Make pre-CAC results valid only for ETSI domain

2017-03-06T12:54:15+00:00

DFS requirement for ETSI domain (section 4.7.1.4 in ETSI EN 301 893 V1.8.1) is the only one which explicitly states that once DFS channel is marked as available afer the CAC, this channel will remain in available state even moving to a different operating channel. But the same is not explicitly stated in FCC DFS requirement. Also, Pre-CAC requriements are not explicitly mentioned in FCC requirement. Current implementation in keeping DFS channel in available state is same as described in ETSI domain. For non-ETSI DFS domain, this patch gives a grace period of 2 seconds since the completion of successful CAC before moving the channel's DFS state to 'usable' from 'available' state. The same grace period is checked against the channel's dfs_state_entered timestamp while deciding if a DFS channel is available for operation. There is a new radar event, NL80211_RADAR_PRE_CAC_EXPIRED, reported when DFS channel is moved from available to usable state after the grace period. Also make sure the DFS channel state is reset to usable once the beaconing operation on that channel is brought down (like stop_ap, leave_ibss and leave_mesh) in non-ETSI domain. Signed-off-by: Vasanthakumar Thiagarajan Signed-off-by: Johannes Berg

cfg80211: mesh: track (and thus validate) beacon interval

2016-10-27T07:08:45+00:00

This is needed for beacon interval validation; if we don't store it, then new interfaces added won't validate that the beacon interval is the same as existing ones. Fix this. Signed-off-by: Johannes Berg

cfg80211: remove enum ieee80211_band

2016-04-12T13:56:15+00:00

This enum is already perfectly aliased to enum nl80211_band, and the only reason for it is that we get IEEE80211_NUM_BANDS out of it. There's no really good reason to not declare the number of bands in nl80211 though, so do that and remove the cfg80211 one. Signed-off-by: Johannes Berg

cfg80211: export interface stopping function

2014-05-06T13:16:34+00:00

This exports a new cfg80211_stop_iface() function. This is intended for driver internal interface combination management and channel switching. Due to locking issues (it re-enters driver) the call is asynchronous and uses cfg80211 event list/worker. Signed-off-by: Michal Kazior Signed-off-by: Johannes Berg