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mirror of https://git.FreeBSD.org/src.git synced 2024-12-23 11:18:54 +00:00
freebsd/sys/net80211/ieee80211_input.c
Sam Leffler 9089c48c13 when receiving a frame w/ a bad version number don't unref the node; the
driver is responsible for that

Obtained from:	madwifi
2004-04-02 22:47:11 +00:00

1173 lines
32 KiB
C

/*-
* Copyright (c) 2001 Atsushi Onoe
* Copyright (c) 2002, 2003 Sam Leffler, Errno Consulting
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/endian.h>
#include <sys/errno.h>
#include <sys/bus.h>
#include <sys/proc.h>
#include <sys/sysctl.h>
#include <machine/atomic.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_media.h>
#include <net/if_arp.h>
#include <net/ethernet.h>
#include <net/if_llc.h>
#include <net80211/ieee80211_var.h>
#include <net/bpf.h>
#ifdef INET
#include <netinet/in.h>
#include <netinet/if_ether.h>
#endif
/*
* Process a received frame. The node associated with the sender
* should be supplied. If nothing was found in the node table then
* the caller is assumed to supply a reference to ic_bss instead.
* The RSSI and a timestamp are also supplied. The RSSI data is used
* during AP scanning to select a AP to associate with; it can have
* any units so long as values have consistent units and higher values
* mean ``better signal''. The receive timestamp is currently not used
* by the 802.11 layer.
*/
void
ieee80211_input(struct ifnet *ifp, struct mbuf *m, struct ieee80211_node *ni,
int rssi, u_int32_t rstamp)
{
struct ieee80211com *ic = (void *)ifp;
struct ieee80211_frame *wh;
struct ether_header *eh;
struct mbuf *m1;
int len;
u_int8_t dir, type, subtype;
u_int8_t *bssid;
u_int16_t rxseq;
KASSERT(ni != NULL, ("null node"));
/* trim CRC here so WEP can find its own CRC at the end of packet. */
if (m->m_flags & M_HASFCS) {
m_adj(m, -IEEE80211_CRC_LEN);
m->m_flags &= ~M_HASFCS;
}
KASSERT(m->m_pkthdr.len >= sizeof(struct ieee80211_frame_min),
("frame length too short: %u", m->m_pkthdr.len));
/*
* In monitor mode, send everything directly to bpf.
* XXX may want to include the CRC
*/
if (ic->ic_opmode == IEEE80211_M_MONITOR)
goto out;
wh = mtod(m, struct ieee80211_frame *);
if ((wh->i_fc[0] & IEEE80211_FC0_VERSION_MASK) !=
IEEE80211_FC0_VERSION_0) {
if (ifp->if_flags & IFF_DEBUG)
if_printf(ifp, "receive packet with wrong version: %x\n",
wh->i_fc[0]);
ic->ic_stats.is_rx_badversion++;
goto err;
}
dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
/*
* NB: We are not yet prepared to handle control frames,
* but permitting drivers to send them to us allows
* them to go through bpf tapping at the 802.11 layer.
*/
if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) {
/* XXX statistic */
IEEE80211_DPRINTF2(("%s: frame too short, len %u\n",
__func__, m->m_pkthdr.len));
ic->ic_stats.is_rx_tooshort++;
goto out; /* XXX */
}
if (ic->ic_state != IEEE80211_S_SCAN) {
switch (ic->ic_opmode) {
case IEEE80211_M_STA:
if (!IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_bssid)) {
/* not interested in */
IEEE80211_DPRINTF2(("%s: discard frame from "
"bss %s\n", __func__,
ether_sprintf(wh->i_addr2)));
ic->ic_stats.is_rx_wrongbss++;
goto out;
}
break;
case IEEE80211_M_IBSS:
case IEEE80211_M_AHDEMO:
case IEEE80211_M_HOSTAP:
if (dir == IEEE80211_FC1_DIR_NODS)
bssid = wh->i_addr3;
else
bssid = wh->i_addr1;
if (!IEEE80211_ADDR_EQ(bssid, ic->ic_bss->ni_bssid) &&
!IEEE80211_ADDR_EQ(bssid, ifp->if_broadcastaddr)) {
/* not interested in */
IEEE80211_DPRINTF2(("%s: discard frame from "
"bss %s\n", __func__,
ether_sprintf(bssid)));
ic->ic_stats.is_rx_wrongbss++;
goto out;
}
break;
case IEEE80211_M_MONITOR:
goto out;
default:
/* XXX catch bad values */
break;
}
ni->ni_rssi = rssi;
ni->ni_rstamp = rstamp;
rxseq = ni->ni_rxseq;
ni->ni_rxseq =
le16toh(*(u_int16_t *)wh->i_seq) >> IEEE80211_SEQ_SEQ_SHIFT;
/* TODO: fragment */
if ((wh->i_fc[1] & IEEE80211_FC1_RETRY) &&
rxseq == ni->ni_rxseq) {
/* duplicate, silently discarded */
ic->ic_stats.is_rx_dup++; /* XXX per-station stat */
goto out;
}
ni->ni_inact = 0;
}
switch (type) {
case IEEE80211_FC0_TYPE_DATA:
switch (ic->ic_opmode) {
case IEEE80211_M_STA:
if (dir != IEEE80211_FC1_DIR_FROMDS) {
ic->ic_stats.is_rx_wrongdir++;
goto out;
}
if ((ifp->if_flags & IFF_SIMPLEX) &&
IEEE80211_IS_MULTICAST(wh->i_addr1) &&
IEEE80211_ADDR_EQ(wh->i_addr3, ic->ic_myaddr)) {
/*
* In IEEE802.11 network, multicast packet
* sent from me is broadcasted from AP.
* It should be silently discarded for
* SIMPLEX interface.
*/
ic->ic_stats.is_rx_mcastecho++;
goto out;
}
break;
case IEEE80211_M_IBSS:
case IEEE80211_M_AHDEMO:
if (dir != IEEE80211_FC1_DIR_NODS) {
ic->ic_stats.is_rx_wrongdir++;
goto out;
}
break;
case IEEE80211_M_HOSTAP:
if (dir != IEEE80211_FC1_DIR_TODS) {
ic->ic_stats.is_rx_wrongdir++;
goto out;
}
/* check if source STA is associated */
if (ni == ic->ic_bss) {
IEEE80211_DPRINTF(("%s: data from unknown src "
"%s\n", __func__,
ether_sprintf(wh->i_addr2)));
/* NB: caller deals with reference */
ni = ieee80211_dup_bss(ic, wh->i_addr2);
if (ni != NULL) {
IEEE80211_SEND_MGMT(ic, ni,
IEEE80211_FC0_SUBTYPE_DEAUTH,
IEEE80211_REASON_NOT_AUTHED);
ieee80211_free_node(ic, ni);
}
ic->ic_stats.is_rx_notassoc++;
goto err;
}
if (ni->ni_associd == 0) {
IEEE80211_DPRINTF(("ieee80211_input: "
"data from unassoc src %s\n",
ether_sprintf(wh->i_addr2)));
IEEE80211_SEND_MGMT(ic, ni,
IEEE80211_FC0_SUBTYPE_DISASSOC,
IEEE80211_REASON_NOT_ASSOCED);
ieee80211_unref_node(&ni);
ic->ic_stats.is_rx_notassoc++;
goto err;
}
break;
case IEEE80211_M_MONITOR:
break;
}
if (wh->i_fc[1] & IEEE80211_FC1_WEP) {
if (ic->ic_flags & IEEE80211_F_WEPON) {
m = ieee80211_wep_crypt(ifp, m, 0);
if (m == NULL) {
ic->ic_stats.is_rx_wepfail++;
goto err;
}
wh = mtod(m, struct ieee80211_frame *);
} else {
ic->ic_stats.is_rx_nowep++;
goto out;
}
}
/* copy to listener after decrypt */
if (ic->ic_rawbpf)
bpf_mtap(ic->ic_rawbpf, m);
m = ieee80211_decap(ifp, m);
if (m == NULL) {
ic->ic_stats.is_rx_decap++;
goto err;
}
ifp->if_ipackets++;
/* perform as a bridge within the AP */
m1 = NULL;
if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
eh = mtod(m, struct ether_header *);
if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
m1 = m_copypacket(m, M_DONTWAIT);
if (m1 == NULL)
ifp->if_oerrors++;
else
m1->m_flags |= M_MCAST;
} else {
ni = ieee80211_find_node(ic, eh->ether_dhost);
if (ni != NULL) {
if (ni->ni_associd != 0) {
m1 = m;
m = NULL;
}
ieee80211_unref_node(&ni);
}
}
if (m1 != NULL) {
#ifdef ALTQ
if (ALTQ_IS_ENABLED(&ifp->if_snd))
altq_etherclassify(&ifp->if_snd, m1,
&pktattr);
#endif
len = m1->m_pkthdr.len;
IF_ENQUEUE(&ifp->if_snd, m1);
if (m != NULL)
ifp->if_omcasts++;
ifp->if_obytes += len;
}
}
if (m != NULL)
(*ifp->if_input)(ifp, m);
return;
case IEEE80211_FC0_TYPE_MGT:
if (dir != IEEE80211_FC1_DIR_NODS) {
ic->ic_stats.is_rx_wrongdir++;
goto err;
}
if (ic->ic_opmode == IEEE80211_M_AHDEMO) {
ic->ic_stats.is_rx_ahdemo_mgt++;
goto out;
}
subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
/* drop frames without interest */
if (ic->ic_state == IEEE80211_S_SCAN) {
if (subtype != IEEE80211_FC0_SUBTYPE_BEACON &&
subtype != IEEE80211_FC0_SUBTYPE_PROBE_RESP) {
ic->ic_stats.is_rx_mgtdiscard++;
goto out;
}
} else {
if (ic->ic_opmode != IEEE80211_M_IBSS &&
subtype == IEEE80211_FC0_SUBTYPE_BEACON) {
ic->ic_stats.is_rx_mgtdiscard++;
goto out;
}
}
if (ifp->if_flags & IFF_DEBUG) {
/* avoid to print too many frames */
int doprint = 0;
switch (subtype) {
case IEEE80211_FC0_SUBTYPE_BEACON:
if (ic->ic_state == IEEE80211_S_SCAN)
doprint = 1;
break;
case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
if (ic->ic_opmode == IEEE80211_M_IBSS)
doprint = 1;
break;
default:
doprint = 1;
break;
}
#ifdef IEEE80211_DEBUG
doprint += ieee80211_debug;
#endif
if (doprint)
if_printf(ifp, "received %s from %s rssi %d\n",
ieee80211_mgt_subtype_name[subtype
>> IEEE80211_FC0_SUBTYPE_SHIFT],
ether_sprintf(wh->i_addr2), rssi);
}
if (ic->ic_rawbpf)
bpf_mtap(ic->ic_rawbpf, m);
(*ic->ic_recv_mgmt)(ic, m, ni, subtype, rssi, rstamp);
m_freem(m);
return;
case IEEE80211_FC0_TYPE_CTL:
ic->ic_stats.is_rx_ctl++;
goto out;
default:
IEEE80211_DPRINTF(("%s: bad type %x\n", __func__, type));
/* should not come here */
break;
}
err:
ifp->if_ierrors++;
out:
if (m != NULL) {
if (ic->ic_rawbpf)
bpf_mtap(ic->ic_rawbpf, m);
m_freem(m);
}
}
struct mbuf *
ieee80211_decap(struct ifnet *ifp, struct mbuf *m)
{
struct ether_header *eh;
struct ieee80211_frame wh;
struct llc *llc;
if (m->m_len < sizeof(wh) + sizeof(*llc)) {
m = m_pullup(m, sizeof(wh) + sizeof(*llc));
if (m == NULL)
return NULL;
}
memcpy(&wh, mtod(m, caddr_t), sizeof(wh));
llc = (struct llc *)(mtod(m, caddr_t) + sizeof(wh));
if (llc->llc_dsap == LLC_SNAP_LSAP && llc->llc_ssap == LLC_SNAP_LSAP &&
llc->llc_control == LLC_UI && llc->llc_snap.org_code[0] == 0 &&
llc->llc_snap.org_code[1] == 0 && llc->llc_snap.org_code[2] == 0) {
m_adj(m, sizeof(wh) + sizeof(struct llc) - sizeof(*eh));
llc = NULL;
} else {
m_adj(m, sizeof(wh) - sizeof(*eh));
}
eh = mtod(m, struct ether_header *);
switch (wh.i_fc[1] & IEEE80211_FC1_DIR_MASK) {
case IEEE80211_FC1_DIR_NODS:
IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
break;
case IEEE80211_FC1_DIR_TODS:
IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
break;
case IEEE80211_FC1_DIR_FROMDS:
IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr3);
break;
case IEEE80211_FC1_DIR_DSTODS:
/* not yet supported */
IEEE80211_DPRINTF(("%s: DS to DS\n", __func__));
m_freem(m);
return NULL;
}
#ifdef ALIGNED_POINTER
if (!ALIGNED_POINTER(mtod(m, caddr_t) + sizeof(*eh), u_int32_t)) {
struct mbuf *n, *n0, **np;
caddr_t newdata;
int off, pktlen;
n0 = NULL;
np = &n0;
off = 0;
pktlen = m->m_pkthdr.len;
while (pktlen > off) {
if (n0 == NULL) {
MGETHDR(n, M_DONTWAIT, MT_DATA);
if (n == NULL) {
m_freem(m);
return NULL;
}
M_MOVE_PKTHDR(n, m);
n->m_len = MHLEN;
} else {
MGET(n, M_DONTWAIT, MT_DATA);
if (n == NULL) {
m_freem(m);
m_freem(n0);
return NULL;
}
n->m_len = MLEN;
}
if (pktlen - off >= MINCLSIZE) {
MCLGET(n, M_DONTWAIT);
if (n->m_flags & M_EXT)
n->m_len = n->m_ext.ext_size;
}
if (n0 == NULL) {
newdata =
(caddr_t)ALIGN(n->m_data + sizeof(*eh)) -
sizeof(*eh);
n->m_len -= newdata - n->m_data;
n->m_data = newdata;
}
if (n->m_len > pktlen - off)
n->m_len = pktlen - off;
m_copydata(m, off, n->m_len, mtod(n, caddr_t));
off += n->m_len;
*np = n;
np = &n->m_next;
}
m_freem(m);
m = n0;
}
#endif /* ALIGNED_POINTER */
if (llc != NULL) {
eh = mtod(m, struct ether_header *);
eh->ether_type = htons(m->m_pkthdr.len - sizeof(*eh));
}
return m;
}
/*
* Install received rate set information in the node's state block.
*/
static int
ieee80211_setup_rates(struct ieee80211com *ic, struct ieee80211_node *ni,
u_int8_t *rates, u_int8_t *xrates, int flags)
{
struct ieee80211_rateset *rs = &ni->ni_rates;
memset(rs, 0, sizeof(*rs));
rs->rs_nrates = rates[1];
memcpy(rs->rs_rates, rates + 2, rs->rs_nrates);
if (xrates != NULL) {
u_int8_t nxrates;
/*
* Tack on 11g extended supported rate element.
*/
nxrates = xrates[1];
if (rs->rs_nrates + nxrates > IEEE80211_RATE_MAXSIZE) {
nxrates = IEEE80211_RATE_MAXSIZE - rs->rs_nrates;
IEEE80211_DPRINTF(("%s: extended rate set too large;"
" only using %u of %u rates\n",
__func__, nxrates, xrates[1]));
ic->ic_stats.is_rx_rstoobig++;
}
memcpy(rs->rs_rates + rs->rs_nrates, xrates+2, nxrates);
rs->rs_nrates += nxrates;
}
return ieee80211_fix_rate(ic, ni, flags);
}
/* Verify the existence and length of __elem or get out. */
#define IEEE80211_VERIFY_ELEMENT(__elem, __maxlen) do { \
if ((__elem) == NULL) { \
IEEE80211_DPRINTF(("%s: no " #__elem "in %s frame\n", \
__func__, ieee80211_mgt_subtype_name[subtype >> \
IEEE80211_FC0_SUBTYPE_SHIFT])); \
ic->ic_stats.is_rx_elem_missing++; \
return; \
} \
if ((__elem)[1] > (__maxlen)) { \
IEEE80211_DPRINTF(("%s: bad " #__elem " len %d in %s " \
"frame from %s\n", __func__, (__elem)[1], \
ieee80211_mgt_subtype_name[subtype >> \
IEEE80211_FC0_SUBTYPE_SHIFT], \
ether_sprintf(wh->i_addr2))); \
ic->ic_stats.is_rx_elem_toobig++; \
return; \
} \
} while (0)
#define IEEE80211_VERIFY_LENGTH(_len, _minlen) do { \
if ((_len) < (_minlen)) { \
IEEE80211_DPRINTF(("%s: %s frame too short from %s\n", \
__func__, \
ieee80211_mgt_subtype_name[subtype >> \
IEEE80211_FC0_SUBTYPE_SHIFT], \
ether_sprintf(wh->i_addr2))); \
ic->ic_stats.is_rx_elem_toosmall++; \
return; \
} \
} while (0)
void
ieee80211_recv_mgmt(struct ieee80211com *ic, struct mbuf *m0,
struct ieee80211_node *ni,
int subtype, int rssi, u_int32_t rstamp)
{
#define ISPROBE(_st) ((_st) == IEEE80211_FC0_SUBTYPE_PROBE_RESP)
struct ifnet *ifp = &ic->ic_if;
struct ieee80211_frame *wh;
u_int8_t *frm, *efrm;
u_int8_t *ssid, *rates, *xrates;
int reassoc, resp, newassoc, allocbs;
wh = mtod(m0, struct ieee80211_frame *);
frm = (u_int8_t *)&wh[1];
efrm = mtod(m0, u_int8_t *) + m0->m_len;
switch (subtype) {
case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
case IEEE80211_FC0_SUBTYPE_BEACON: {
u_int8_t *tstamp, *bintval, *capinfo, *country;
u_int8_t chan, bchan, fhindex, erp;
u_int16_t fhdwell;
if (ic->ic_opmode != IEEE80211_M_IBSS &&
ic->ic_state != IEEE80211_S_SCAN) {
/* XXX: may be useful for background scan */
return;
}
/*
* beacon/probe response frame format
* [8] time stamp
* [2] beacon interval
* [2] capability information
* [tlv] ssid
* [tlv] supported rates
* [tlv] country information
* [tlv] parameter set (FH/DS)
* [tlv] erp information
* [tlv] extended supported rates
*/
IEEE80211_VERIFY_LENGTH(efrm - frm, 12);
tstamp = frm; frm += 8;
bintval = frm; frm += 2;
capinfo = frm; frm += 2;
ssid = rates = xrates = country = NULL;
bchan = ieee80211_chan2ieee(ic, ic->ic_bss->ni_chan);
chan = bchan;
fhdwell = 0;
fhindex = 0;
erp = 0;
while (frm < efrm) {
switch (*frm) {
case IEEE80211_ELEMID_SSID:
ssid = frm;
break;
case IEEE80211_ELEMID_RATES:
rates = frm;
break;
case IEEE80211_ELEMID_COUNTRY:
country = frm;
break;
case IEEE80211_ELEMID_FHPARMS:
if (ic->ic_phytype == IEEE80211_T_FH) {
fhdwell = (frm[3] << 8) | frm[2];
chan = IEEE80211_FH_CHAN(frm[4], frm[5]);
fhindex = frm[6];
}
break;
case IEEE80211_ELEMID_DSPARMS:
/*
* XXX hack this since depending on phytype
* is problematic for multi-mode devices.
*/
if (ic->ic_phytype != IEEE80211_T_FH)
chan = frm[2];
break;
case IEEE80211_ELEMID_TIM:
break;
case IEEE80211_ELEMID_XRATES:
xrates = frm;
break;
case IEEE80211_ELEMID_ERP:
if (frm[1] != 1) {
IEEE80211_DPRINTF(("%s: invalid ERP "
"element; length %u, expecting "
"1\n", __func__, frm[1]));
ic->ic_stats.is_rx_elem_toobig++;
break;
}
erp = frm[2];
break;
default:
IEEE80211_DPRINTF2(("%s: element id %u/len %u "
"ignored\n", __func__, *frm, frm[1]));
ic->ic_stats.is_rx_elem_unknown++;
break;
}
frm += frm[1] + 2;
}
IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE);
IEEE80211_VERIFY_ELEMENT(ssid, IEEE80211_NWID_LEN);
if (
#if IEEE80211_CHAN_MAX < 255
chan > IEEE80211_CHAN_MAX ||
#endif
isclr(ic->ic_chan_active, chan)) {
IEEE80211_DPRINTF(("%s: ignore %s with invalid channel "
"%u\n", __func__,
ISPROBE(subtype) ? "probe response" : "beacon",
chan));
ic->ic_stats.is_rx_badchan++;
return;
}
if (chan != bchan && ic->ic_phytype != IEEE80211_T_FH) {
/*
* Frame was received on a channel different from the
* one indicated in the DS params element id;
* silently discard it.
*
* NB: this can happen due to signal leakage.
* But we should take it for FH phy because
* the rssi value should be correct even for
* different hop pattern in FH.
*/
IEEE80211_DPRINTF(("%s: ignore %s on channel %u marked "
"for channel %u\n", __func__,
ISPROBE(subtype) ? "probe response" : "beacon",
bchan, chan));
ic->ic_stats.is_rx_chanmismatch++;
return;
}
/*
* Use mac and channel for lookup so we collect all
* potential AP's when scanning. Otherwise we may
* see the same AP on multiple channels and will only
* record the last one. We could filter APs here based
* on rssi, etc. but leave that to the end of the scan
* so we can keep the selection criteria in one spot.
* This may result in a bloat of the scanned AP list but
* it shouldn't be too much.
*/
ni = ieee80211_lookup_node(ic, wh->i_addr2,
&ic->ic_channels[chan]);
#ifdef IEEE80211_DEBUG
if (ieee80211_debug &&
(ni == NULL || ic->ic_state == IEEE80211_S_SCAN)) {
printf("%s: %s%s on chan %u (bss chan %u) ",
__func__, (ni == NULL ? "new " : ""),
ISPROBE(subtype) ? "probe response" : "beacon",
chan, bchan);
ieee80211_print_essid(ssid + 2, ssid[1]);
printf(" from %s\n", ether_sprintf(wh->i_addr2));
printf("%s: caps 0x%x bintval %u erp 0x%x\n",
__func__, le16toh(*(u_int16_t *)capinfo),
le16toh(*(u_int16_t *)bintval), erp);
if (country)
printf("%s: country info %*D\n",
__func__, country[1], country+2, " ");
}
#endif
if (ni == NULL) {
ni = ieee80211_alloc_node(ic, wh->i_addr2);
if (ni == NULL) {
ic->ic_stats.is_rx_nodealloc++;
return;
}
ni->ni_esslen = ssid[1];
memset(ni->ni_essid, 0, sizeof(ni->ni_essid));
memcpy(ni->ni_essid, ssid + 2, ssid[1]);
} else if (ssid[1] != 0 && ISPROBE(subtype)) {
/*
* Update ESSID at probe response to adopt hidden AP by
* Lucent/Cisco, which announces null ESSID in beacon.
*/
ni->ni_esslen = ssid[1];
memset(ni->ni_essid, 0, sizeof(ni->ni_essid));
memcpy(ni->ni_essid, ssid + 2, ssid[1]);
}
IEEE80211_ADDR_COPY(ni->ni_bssid, wh->i_addr3);
ni->ni_rssi = rssi;
ni->ni_rstamp = rstamp;
memcpy(ni->ni_tstamp, tstamp, sizeof(ni->ni_tstamp));
ni->ni_intval = le16toh(*(u_int16_t *)bintval);
ni->ni_capinfo = le16toh(*(u_int16_t *)capinfo);
/* XXX validate channel # */
ni->ni_chan = &ic->ic_channels[chan];
ni->ni_fhdwell = fhdwell;
ni->ni_fhindex = fhindex;
ni->ni_erp = erp;
/* NB: must be after ni_chan is setup */
ieee80211_setup_rates(ic, ni, rates, xrates, IEEE80211_F_DOSORT);
ieee80211_unref_node(&ni);
break;
}
case IEEE80211_FC0_SUBTYPE_PROBE_REQ: {
u_int8_t rate;
if (ic->ic_opmode == IEEE80211_M_STA)
return;
if (ic->ic_state != IEEE80211_S_RUN)
return;
/*
* prreq frame format
* [tlv] ssid
* [tlv] supported rates
* [tlv] extended supported rates
*/
ssid = rates = xrates = NULL;
while (frm < efrm) {
switch (*frm) {
case IEEE80211_ELEMID_SSID:
ssid = frm;
break;
case IEEE80211_ELEMID_RATES:
rates = frm;
break;
case IEEE80211_ELEMID_XRATES:
xrates = frm;
break;
}
frm += frm[1] + 2;
}
IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE);
IEEE80211_VERIFY_ELEMENT(ssid, IEEE80211_NWID_LEN);
if (ssid[1] != 0 &&
(ssid[1] != ic->ic_bss->ni_esslen ||
memcmp(ssid + 2, ic->ic_bss->ni_essid, ic->ic_bss->ni_esslen) != 0)) {
#ifdef IEEE80211_DEBUG
if (ieee80211_debug) {
printf("%s: ssid unmatch ", __func__);
ieee80211_print_essid(ssid + 2, ssid[1]);
printf(" from %s\n", ether_sprintf(wh->i_addr2));
}
#endif
ic->ic_stats.is_rx_ssidmismatch++;
return;
}
if (ni == ic->ic_bss) {
ni = ieee80211_dup_bss(ic, wh->i_addr2);
if (ni == NULL) {
ic->ic_stats.is_rx_nodealloc++;
return;
}
IEEE80211_DPRINTF(("%s: new req from %s\n",
__func__, ether_sprintf(wh->i_addr2)));
allocbs = 1;
} else
allocbs = 0;
ni->ni_rssi = rssi;
ni->ni_rstamp = rstamp;
rate = ieee80211_setup_rates(ic, ni, rates, xrates,
IEEE80211_F_DOSORT | IEEE80211_F_DOFRATE
| IEEE80211_F_DONEGO | IEEE80211_F_DODEL);
if (rate & IEEE80211_RATE_BASIC) {
IEEE80211_DPRINTF(("%s: rate negotiation failed: %s\n",
__func__,ether_sprintf(wh->i_addr2)));
} else {
IEEE80211_SEND_MGMT(ic, ni,
IEEE80211_FC0_SUBTYPE_PROBE_RESP, 0);
}
if (allocbs) {
/* XXX just use free? */
if (ic->ic_opmode == IEEE80211_M_HOSTAP)
ieee80211_free_node(ic, ni);
else
ieee80211_unref_node(&ni);
}
break;
}
case IEEE80211_FC0_SUBTYPE_AUTH: {
u_int16_t algo, seq, status;
/*
* auth frame format
* [2] algorithm
* [2] sequence
* [2] status
* [tlv*] challenge
*/
IEEE80211_VERIFY_LENGTH(efrm - frm, 6);
algo = le16toh(*(u_int16_t *)frm);
seq = le16toh(*(u_int16_t *)(frm + 2));
status = le16toh(*(u_int16_t *)(frm + 4));
if (algo != IEEE80211_AUTH_ALG_OPEN) {
/* TODO: shared key auth */
IEEE80211_DPRINTF(("%s: unsupported auth %d from %s\n",
__func__, algo, ether_sprintf(wh->i_addr2)));
ic->ic_stats.is_rx_auth_unsupported++;
return;
}
switch (ic->ic_opmode) {
case IEEE80211_M_IBSS:
if (ic->ic_state != IEEE80211_S_RUN || seq != 1) {
IEEE80211_DPRINTF(("%s: discard auth from %s; "
"state %u, seq %u\n", __func__,
ether_sprintf(wh->i_addr2),
ic->ic_state, seq));
ic->ic_stats.is_rx_bad_auth++;
break;
}
ieee80211_new_state(ic, IEEE80211_S_AUTH,
wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK);
break;
case IEEE80211_M_AHDEMO:
/* should not come here */
break;
case IEEE80211_M_HOSTAP:
if (ic->ic_state != IEEE80211_S_RUN || seq != 1) {
IEEE80211_DPRINTF(("%s: discard auth from %s; "
"state %u, seq %u\n", __func__,
ether_sprintf(wh->i_addr2),
ic->ic_state, seq));
ic->ic_stats.is_rx_bad_auth++;
break;
}
if (ni == ic->ic_bss) {
ni = ieee80211_alloc_node(ic, wh->i_addr2);
if (ni == NULL) {
ic->ic_stats.is_rx_nodealloc++;
return;
}
IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_bss->ni_bssid);
ni->ni_rssi = rssi;
ni->ni_rstamp = rstamp;
ni->ni_chan = ic->ic_bss->ni_chan;
allocbs = 1;
} else
allocbs = 0;
IEEE80211_SEND_MGMT(ic, ni,
IEEE80211_FC0_SUBTYPE_AUTH, 2);
if (ifp->if_flags & IFF_DEBUG)
if_printf(ifp, "station %s %s authenticated\n",
(allocbs ? "newly" : "already"),
ether_sprintf(ni->ni_macaddr));
break;
case IEEE80211_M_STA:
if (ic->ic_state != IEEE80211_S_AUTH || seq != 2) {
IEEE80211_DPRINTF(("%s: discard auth from %s; "
"state %u, seq %u\n", __func__,
ether_sprintf(wh->i_addr2),
ic->ic_state, seq));
ic->ic_stats.is_rx_bad_auth++;
break;
}
if (status != 0) {
if_printf(&ic->ic_if,
"authentication failed (reason %d) for %s\n",
status,
ether_sprintf(wh->i_addr3));
if (ni != ic->ic_bss)
ni->ni_fails++;
ic->ic_stats.is_rx_auth_fail++;
return;
}
ieee80211_new_state(ic, IEEE80211_S_ASSOC,
wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK);
break;
case IEEE80211_M_MONITOR:
break;
}
break;
}
case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
case IEEE80211_FC0_SUBTYPE_REASSOC_REQ: {
u_int16_t capinfo, bintval;
if (ic->ic_opmode != IEEE80211_M_HOSTAP ||
(ic->ic_state != IEEE80211_S_RUN))
return;
if (subtype == IEEE80211_FC0_SUBTYPE_REASSOC_REQ) {
reassoc = 1;
resp = IEEE80211_FC0_SUBTYPE_REASSOC_RESP;
} else {
reassoc = 0;
resp = IEEE80211_FC0_SUBTYPE_ASSOC_RESP;
}
/*
* asreq frame format
* [2] capability information
* [2] listen interval
* [6*] current AP address (reassoc only)
* [tlv] ssid
* [tlv] supported rates
* [tlv] extended supported rates
*/
IEEE80211_VERIFY_LENGTH(efrm - frm, (reassoc ? 10 : 4));
if (!IEEE80211_ADDR_EQ(wh->i_addr3, ic->ic_bss->ni_bssid)) {
IEEE80211_DPRINTF(("%s: ignore other bss from %s\n",
__func__, ether_sprintf(wh->i_addr2)));
ic->ic_stats.is_rx_assoc_bss++;
return;
}
capinfo = le16toh(*(u_int16_t *)frm); frm += 2;
bintval = le16toh(*(u_int16_t *)frm); frm += 2;
if (reassoc)
frm += 6; /* ignore current AP info */
ssid = rates = xrates = NULL;
while (frm < efrm) {
switch (*frm) {
case IEEE80211_ELEMID_SSID:
ssid = frm;
break;
case IEEE80211_ELEMID_RATES:
rates = frm;
break;
case IEEE80211_ELEMID_XRATES:
xrates = frm;
break;
}
frm += frm[1] + 2;
}
IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE);
IEEE80211_VERIFY_ELEMENT(ssid, IEEE80211_NWID_LEN);
if (ssid[1] != ic->ic_bss->ni_esslen ||
memcmp(ssid + 2, ic->ic_bss->ni_essid, ssid[1]) != 0) {
#ifdef IEEE80211_DEBUG
if (ieee80211_debug) {
printf("%s: ssid unmatch ", __func__);
ieee80211_print_essid(ssid + 2, ssid[1]);
printf(" from %s\n", ether_sprintf(wh->i_addr2));
}
#endif
ic->ic_stats.is_rx_ssidmismatch++;
return;
}
if (ni == ic->ic_bss) {
IEEE80211_DPRINTF(("%s: not authenticated for %s\n",
__func__, ether_sprintf(wh->i_addr2)));
ni = ieee80211_dup_bss(ic, wh->i_addr2);
if (ni != NULL) {
IEEE80211_SEND_MGMT(ic, ni,
IEEE80211_FC0_SUBTYPE_DEAUTH,
IEEE80211_REASON_ASSOC_NOT_AUTHED);
ieee80211_free_node(ic, ni);
}
ic->ic_stats.is_rx_assoc_notauth++;
return;
}
/* XXX per-node cipher suite */
/* XXX some stations use the privacy bit for handling APs
that suport both encrypted and unencrypted traffic */
if ((capinfo & IEEE80211_CAPINFO_ESS) == 0 ||
(capinfo & IEEE80211_CAPINFO_PRIVACY) !=
((ic->ic_flags & IEEE80211_F_WEPON) ?
IEEE80211_CAPINFO_PRIVACY : 0)) {
IEEE80211_DPRINTF(("%s: capability mismatch %x for %s\n",
__func__, capinfo, ether_sprintf(wh->i_addr2)));
ni->ni_associd = 0;
IEEE80211_SEND_MGMT(ic, ni, resp,
IEEE80211_STATUS_CAPINFO);
ic->ic_stats.is_rx_assoc_capmismatch++;
return;
}
ieee80211_setup_rates(ic, ni, rates, xrates,
IEEE80211_F_DOSORT | IEEE80211_F_DOFRATE |
IEEE80211_F_DONEGO | IEEE80211_F_DODEL);
if (ni->ni_rates.rs_nrates == 0) {
IEEE80211_DPRINTF(("%s: rate unmatch for %s\n",
__func__, ether_sprintf(wh->i_addr2)));
ni->ni_associd = 0;
IEEE80211_SEND_MGMT(ic, ni, resp,
IEEE80211_STATUS_BASIC_RATE);
ic->ic_stats.is_rx_assoc_norate++;
return;
}
ni->ni_rssi = rssi;
ni->ni_rstamp = rstamp;
ni->ni_intval = bintval;
ni->ni_capinfo = capinfo;
ni->ni_chan = ic->ic_bss->ni_chan;
ni->ni_fhdwell = ic->ic_bss->ni_fhdwell;
ni->ni_fhindex = ic->ic_bss->ni_fhindex;
if (ni->ni_associd == 0) {
/* XXX handle rollover at 2007 */
/* XXX guarantee uniqueness */
ni->ni_associd = 0xc000 | ic->ic_bss->ni_associd++;
newassoc = 1;
} else
newassoc = 0;
/* XXX for 11g must turn off short slot time if long
slot time sta associates */
IEEE80211_SEND_MGMT(ic, ni, resp, IEEE80211_STATUS_SUCCESS);
if (ifp->if_flags & IFF_DEBUG)
if_printf(ifp, "station %s %s associated\n",
(newassoc ? "newly" : "already"),
ether_sprintf(ni->ni_macaddr));
/* give driver a chance to setup state like ni_txrate */
if (ic->ic_newassoc)
(*ic->ic_newassoc)(ic, ni, newassoc);
break;
}
case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
case IEEE80211_FC0_SUBTYPE_REASSOC_RESP: {
u_int16_t status;
if (ic->ic_opmode != IEEE80211_M_STA ||
ic->ic_state != IEEE80211_S_ASSOC)
return;
/*
* asresp frame format
* [2] capability information
* [2] status
* [2] association ID
* [tlv] supported rates
* [tlv] extended supported rates
*/
IEEE80211_VERIFY_LENGTH(efrm - frm, 6);
ni = ic->ic_bss;
ni->ni_capinfo = le16toh(*(u_int16_t *)frm);
frm += 2;
status = le16toh(*(u_int16_t *)frm);
frm += 2;
if (status != 0) {
if_printf(ifp, "association failed (reason %d) for %s\n",
status, ether_sprintf(wh->i_addr3));
if (ni != ic->ic_bss)
ni->ni_fails++;
ic->ic_stats.is_rx_auth_fail++;
return;
}
ni->ni_associd = le16toh(*(u_int16_t *)frm);
frm += 2;
rates = xrates = NULL;
while (frm < efrm) {
switch (*frm) {
case IEEE80211_ELEMID_RATES:
rates = frm;
break;
case IEEE80211_ELEMID_XRATES:
xrates = frm;
break;
}
frm += frm[1] + 2;
}
IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE);
ieee80211_setup_rates(ic, ni, rates, xrates,
IEEE80211_F_DOSORT | IEEE80211_F_DOFRATE |
IEEE80211_F_DONEGO | IEEE80211_F_DODEL);
if (ni->ni_rates.rs_nrates != 0)
ieee80211_new_state(ic, IEEE80211_S_RUN,
wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK);
break;
}
case IEEE80211_FC0_SUBTYPE_DEAUTH: {
u_int16_t reason;
/*
* deauth frame format
* [2] reason
*/
IEEE80211_VERIFY_LENGTH(efrm - frm, 2);
reason = le16toh(*(u_int16_t *)frm);
ic->ic_stats.is_rx_deauth++;
switch (ic->ic_opmode) {
case IEEE80211_M_STA:
ieee80211_new_state(ic, IEEE80211_S_AUTH,
wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK);
break;
case IEEE80211_M_HOSTAP:
if (ni != ic->ic_bss) {
if (ifp->if_flags & IFF_DEBUG)
if_printf(ifp, "station %s deauthenticated"
" by peer (reason %d)\n",
ether_sprintf(ni->ni_macaddr), reason);
/* node will be free'd on return */
ieee80211_unref_node(&ni);
}
break;
default:
break;
}
break;
}
case IEEE80211_FC0_SUBTYPE_DISASSOC: {
u_int16_t reason;
/*
* disassoc frame format
* [2] reason
*/
IEEE80211_VERIFY_LENGTH(efrm - frm, 2);
reason = le16toh(*(u_int16_t *)frm);
ic->ic_stats.is_rx_disassoc++;
switch (ic->ic_opmode) {
case IEEE80211_M_STA:
ieee80211_new_state(ic, IEEE80211_S_ASSOC,
wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK);
break;
case IEEE80211_M_HOSTAP:
if (ni != ic->ic_bss) {
if (ifp->if_flags & IFF_DEBUG)
if_printf(ifp, "station %s disassociated"
" by peer (reason %d)\n",
ether_sprintf(ni->ni_macaddr), reason);
ni->ni_associd = 0;
/* XXX node reclaimed how? */
}
break;
default:
break;
}
break;
}
default:
IEEE80211_DPRINTF(("%s: mgmt frame with subtype 0x%x not "
"handled\n", __func__, subtype));
ic->ic_stats.is_rx_badsubtype++;
break;
}
#undef ISPROBE
}
#undef IEEE80211_VERIFY_LENGTH
#undef IEEE80211_VERIFY_ELEMENT