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| author | Johannes Berg <johannes@sipsolutions.net> | 2007-09-26 17:53:18 +0200 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2007-10-10 16:54:18 -0700 |
| commit | 58d4185e36913d4fc94afa4b4daccb3c9aa01957 (patch) | |
| tree | 77d2e8e423652f5bbf2e29e8c0b3e0aeb7858b9f /Documentation | |
| parent | 628a140ba033ef201706a8c7e767c8a0c0f8326c (diff) | |
| download | lwn-58d4185e36913d4fc94afa4b4daccb3c9aa01957.tar.gz lwn-58d4185e36913d4fc94afa4b4daccb3c9aa01957.zip | |
[MAC80211]: improve radiotap injection
This improves radiotap injection by removing the shortcut over TX handlers
that led to BUGS when injecting frames without setting a rate and also
resulted in various other quirks. Now, TX handlers are run but some
information that was present in the radiotap header is used instead of
automatic settings.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Andy Green <andy@warmcat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/networking/mac80211-injection.txt | 32 |
1 files changed, 26 insertions, 6 deletions
diff --git a/Documentation/networking/mac80211-injection.txt b/Documentation/networking/mac80211-injection.txt index 53ef7a06f49c..84906ef3ed6e 100644 --- a/Documentation/networking/mac80211-injection.txt +++ b/Documentation/networking/mac80211-injection.txt @@ -13,15 +13,35 @@ The radiotap format is discussed in ./Documentation/networking/radiotap-headers.txt. Despite 13 radiotap argument types are currently defined, most only make sense -to appear on received packets. Currently three kinds of argument are used by -the injection code, although it knows to skip any other arguments that are -present (facilitating replay of captured radiotap headers directly): +to appear on received packets. The following information is parsed from the +radiotap headers and used to control injection: - - IEEE80211_RADIOTAP_RATE - u8 arg in 500kbps units (0x02 --> 1Mbps) + * IEEE80211_RADIOTAP_RATE - - IEEE80211_RADIOTAP_ANTENNA - u8 arg, 0x00 = ant1, 0x01 = ant2 + rate in 500kbps units, automatic if invalid or not present - - IEEE80211_RADIOTAP_DBM_TX_POWER - u8 arg, dBm + + * IEEE80211_RADIOTAP_ANTENNA + + antenna to use, automatic if not present + + + * IEEE80211_RADIOTAP_DBM_TX_POWER + + transmit power in dBm, automatic if not present + + + * IEEE80211_RADIOTAP_FLAGS + + IEEE80211_RADIOTAP_F_FCS: FCS will be removed and recalculated + IEEE80211_RADIOTAP_F_WEP: frame will be encrypted if key available + IEEE80211_RADIOTAP_F_FRAG: frame will be fragmented if longer than the + current fragmentation threshold. Note that + this flag is only reliable when software + fragmentation is enabled) + +The injection code can also skip all other currently defined radiotap fields +facilitating replay of captured radiotap headers directly. Here is an example valid radiotap header defining these three parameters |