Fragment and 11s inconsistency

[Monthadar Al Jaberi]

Hi,

I cant verify this yet, but isn't there something wrong in current FreeBSD?

lets say an 11s data frame need to be fragmented in ieee80211_encap:
if (addqos)
		hdrsize = sizeof(struct ieee80211_qosframe);
else
		hdrsize = sizeof(struct ieee80211_frame);
...
if (vap->iv_opmode == IEEE80211_M_MBSS) {
...
		if (!IEEE80211_IS_MULTICAST(eh.ether_dhost))
			hdrsize += IEEE80211_ADDR_LEN;	/* unicast are 4-addr */
		meshhdrsize = sizeof(struct ieee80211_meshcntl);
}
...
if (__predict_true((m->m_flags & M_FF) == 0)) {
		/*
		 * Normal frame.
		 */
		m = ieee80211_mbuf_adjust(vap, hdrspace + meshhdrsize, key, m);
}
M_PREPEND(m, hdrspace + meshhdrsize, M_DONTWAIT);
if (txfrag && !ieee80211_fragment(vap, m, hdrsize,
	    key != NULL ? key->wk_cipher->ic_header : 0, vap->iv_fragthreshold))
		goto bad;

This means we send meshcontrol only in first segment, because we never
add meshhdrsize to hdrsize...


but in mesh_input
switch (type) {
	case IEEE80211_FC0_TYPE_DATA:
...
meshdrlen = sizeof(struct ieee80211_meshcntl) +
		    (mc->mc_flags & 3) * IEEE80211_ADDR_LEN;
		hdrspace += meshdrlen;
...
		/*
		 * Potentially forward packet.  See table s36 (p140)
		 * for the rules.  XXX tap fwd'd packets not for us?
		 */
		if (dir == IEEE80211_FC1_DIR_FROMDS ||
		    !mesh_isucastforme(vap, wh, mc)) {
			mesh_forward(vap, m, mc);
...
if (!IEEE80211_IS_MULTICAST(wh->i_addr1)) {
			m = ieee80211_defrag(ni, m, hdrspace);
			if (m == NULL) {

This seems wrong to me, how can we potentially forward before defragin
the frame? this will fail cause sub-frag have no mesh control as code
shows above.

shouldnt the defrag code be moved above?

I am attaching a patch that both moves the defrag, validates that mesh
control is present and makes 11s data frames QoS and set Mesh control
bit present to 1 as the amendment specifies.

br,
-- 
Monthadar Al Jaberi
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