Date: Mon, 18 Jun 2012 02:08:04 +0000 (UTC) From: Adrian Chadd <adrian@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r237214 - head/sys/net80211 Message-ID: <201206180208.q5I284Gq047328@svn.freebsd.org>
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Author: adrian Date: Mon Jun 18 02:08:04 2012 New Revision: 237214 URL: http://svn.freebsd.org/changeset/base/237214 Log: Extend the radiotap code to be aware of the size of any extra vendor bitmaps that may occur. The way this works is: * the beginning of the radiotap frame has a 32 bit "radiotap" namespace bitmap; * if the vendor bitmap bit is set, then the next bitmap will be interpreted as a vendor bitmap; * this can keep going on and on (ie, more vendor and radiotap namespace bitmaps can be added) until the last bitmap with no "more bitmaps" set. Now, the radiotap code gets its grubby fingers into the supplied radiotap rx/tx buffer and replaces the channel configuration for each frame. I don't know why it's not up to the drivers themselves to do this, but I digress. So, if a vendor bitmap (or two, etc) exists, the offset calculations will be all completely wrong. This particular patch introduces ieee80211_radiotap_attachv(), which includes the number of vendor bitmaps (well, any other bitmaps, vendor or otherwise) between the end of the bitmap/header and the start of the actual radiotap field entries. This makes the radiotap calculations "right", so it correctly calculates where to overwrite the channel configuration. The long term fix is to go through and make each driver update the channel configuration, as some of the fields are already being updated. That, however, is a longer term fix that will need each driver fixed. I leave that as an exercise to someone in the future. Modified: head/sys/net80211/ieee80211_radiotap.c head/sys/net80211/ieee80211_var.h Modified: head/sys/net80211/ieee80211_radiotap.c ============================================================================== --- head/sys/net80211/ieee80211_radiotap.c Sun Jun 17 21:48:40 2012 (r237213) +++ head/sys/net80211/ieee80211_radiotap.c Mon Jun 18 02:08:04 2012 (r237214) @@ -47,13 +47,24 @@ __FBSDID("$FreeBSD$"); #include <net80211/ieee80211_var.h> -static int radiotap_offset(struct ieee80211_radiotap_header *, int); +static int radiotap_offset(struct ieee80211_radiotap_header *, int, int); void ieee80211_radiotap_attach(struct ieee80211com *ic, struct ieee80211_radiotap_header *th, int tlen, uint32_t tx_radiotap, struct ieee80211_radiotap_header *rh, int rlen, uint32_t rx_radiotap) { + ieee80211_radiotap_attachv(ic, th, tlen, 0, tx_radiotap, + rh, rlen, 0, rx_radiotap); +} + +void +ieee80211_radiotap_attachv(struct ieee80211com *ic, + struct ieee80211_radiotap_header *th, + int tlen, int n_tx_v, uint32_t tx_radiotap, + struct ieee80211_radiotap_header *rh, + int rlen, int n_rx_v, uint32_t rx_radiotap) +{ #define B(_v) (1<<(_v)) int off; @@ -63,9 +74,9 @@ ieee80211_radiotap_attach(struct ieee802 /* calculate offset to channel data */ off = -1; if (tx_radiotap & B(IEEE80211_RADIOTAP_CHANNEL)) - off = radiotap_offset(th, IEEE80211_RADIOTAP_CHANNEL); + off = radiotap_offset(th, n_tx_v, IEEE80211_RADIOTAP_CHANNEL); else if (tx_radiotap & B(IEEE80211_RADIOTAP_XCHANNEL)) - off = radiotap_offset(th, IEEE80211_RADIOTAP_XCHANNEL); + off = radiotap_offset(th, n_tx_v, IEEE80211_RADIOTAP_XCHANNEL); if (off == -1) { if_printf(ic->ic_ifp, "%s: no tx channel, radiotap 0x%x\n", __func__, tx_radiotap); @@ -79,9 +90,9 @@ ieee80211_radiotap_attach(struct ieee802 /* calculate offset to channel data */ off = -1; if (rx_radiotap & B(IEEE80211_RADIOTAP_CHANNEL)) - off = radiotap_offset(rh, IEEE80211_RADIOTAP_CHANNEL); + off = radiotap_offset(rh, n_rx_v, IEEE80211_RADIOTAP_CHANNEL); else if (rx_radiotap & B(IEEE80211_RADIOTAP_XCHANNEL)) - off = radiotap_offset(rh, IEEE80211_RADIOTAP_XCHANNEL); + off = radiotap_offset(rh, n_rx_v, IEEE80211_RADIOTAP_XCHANNEL); if (off == -1) { if_printf(ic->ic_ifp, "%s: no rx channel, radiotap 0x%x\n", __func__, rx_radiotap); @@ -260,7 +271,8 @@ ieee80211_radiotap_rx_all(struct ieee802 * known -1 is returned. */ static int -radiotap_offset(struct ieee80211_radiotap_header *rh, int item) +radiotap_offset(struct ieee80211_radiotap_header *rh, + int n_vendor_attributes, int item) { static const struct { size_t align, width; @@ -334,6 +346,8 @@ radiotap_offset(struct ieee80211_radiota int off, i; off = sizeof(struct ieee80211_radiotap_header); + off += n_vendor_attributes * (sizeof(uint32_t)); + for (i = 0; i < IEEE80211_RADIOTAP_EXT; i++) { if ((present & (1<<i)) == 0) continue; Modified: head/sys/net80211/ieee80211_var.h ============================================================================== --- head/sys/net80211/ieee80211_var.h Sun Jun 17 21:48:40 2012 (r237213) +++ head/sys/net80211/ieee80211_var.h Mon Jun 18 02:08:04 2012 (r237214) @@ -705,6 +705,11 @@ void ieee80211_radiotap_attach(struct ie uint32_t tx_radiotap, struct ieee80211_radiotap_header *rh, int rlen, uint32_t rx_radiotap); +void ieee80211_radiotap_attachv(struct ieee80211com *, + struct ieee80211_radiotap_header *th, + int tlen, int n_tx_v, uint32_t tx_radiotap, + struct ieee80211_radiotap_header *rh, + int rlen, int n_rx_v, uint32_t rx_radiotap); void ieee80211_radiotap_detach(struct ieee80211com *); void ieee80211_radiotap_vattach(struct ieee80211vap *); void ieee80211_radiotap_vdetach(struct ieee80211vap *);
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