FreeBSD-5.3/sys/net80211/ieee80211_output.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: src/sys/net80211/ieee80211_output.c,v 1.11 2004/07/27 23:20:45 rwatson Exp $");
#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
/*
* Send a management frame to the specified node. The node pointer
* must have a reference as the pointer will be passed to the driver
* and potentially held for a long time. If the frame is successfully
* dispatched to the driver, then it is responsible for freeing the
* reference (and potentially free'ing up any associated storage).
*/
static int
ieee80211_mgmt_output(struct ifnet *ifp, struct ieee80211_node *ni,
struct mbuf *m, int type)
{
struct ieee80211com *ic = (void *)ifp;
struct ieee80211_frame *wh;
KASSERT(ni != NULL, ("null node"));
ni->ni_inact = 0;
/*
* Yech, hack alert! We want to pass the node down to the
* driver's start routine. If we don't do so then the start
* routine must immediately look it up again and that can
* cause a lock order reversal if, for example, this frame
* is being sent because the station is being timedout and
* the frame being sent is a DEAUTH message. We could stick
* this in an m_tag and tack that on to the mbuf. However
* that's rather expensive to do for every frame so instead
* we stuff it in the rcvif field since outbound frames do
* not (presently) use this.
*/
M_PREPEND(m, sizeof(struct ieee80211_frame), M_DONTWAIT);
if (m == NULL)
return ENOMEM;
KASSERT(m->m_pkthdr.rcvif == NULL, ("rcvif not null"));
m->m_pkthdr.rcvif = (void *)ni;
wh = mtod(m, struct ieee80211_frame *);
wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_MGT | type;
wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
*(u_int16_t *)wh->i_dur = 0;
*(u_int16_t *)wh->i_seq =
htole16(ni->ni_txseq << IEEE80211_SEQ_SEQ_SHIFT);
ni->ni_txseq++;
IEEE80211_ADDR_COPY(wh->i_addr1, ni->ni_macaddr);
IEEE80211_ADDR_COPY(wh->i_addr2, ic->ic_myaddr);
IEEE80211_ADDR_COPY(wh->i_addr3, ni->ni_bssid);
if (ifp->if_flags & IFF_DEBUG) {
/* avoid to print too many frames */
if (ic->ic_opmode == IEEE80211_M_IBSS ||
#ifdef IEEE80211_DEBUG
ieee80211_debug > 1 ||
#endif
(type & IEEE80211_FC0_SUBTYPE_MASK) !=
IEEE80211_FC0_SUBTYPE_PROBE_RESP)
if_printf(ifp, "sending %s to %s on channel %u\n",
ieee80211_mgt_subtype_name[
(type & IEEE80211_FC0_SUBTYPE_MASK)
>> IEEE80211_FC0_SUBTYPE_SHIFT],
ether_sprintf(ni->ni_macaddr),
ieee80211_chan2ieee(ic, ni->ni_chan));
}
IF_ENQUEUE(&ic->ic_mgtq, m);
ifp->if_timer = 1;
if_start(ifp);
return 0;
}
/*
* Encapsulate an outbound data frame. The mbuf chain is updated and
* a reference to the destination node is returned. If an error is
* encountered NULL is returned and the node reference will also be NULL.
*
* NB: The caller is responsible for free'ing a returned node reference.
* The convention is ic_bss is not reference counted; the caller must
* maintain that.
*/
struct mbuf *
ieee80211_encap(struct ifnet *ifp, struct mbuf *m, struct ieee80211_node **pni)
{
struct ieee80211com *ic = (void *)ifp;
struct ether_header eh;
struct ieee80211_frame *wh;
struct ieee80211_node *ni = NULL;
struct llc *llc;
if (m->m_len < sizeof(struct ether_header)) {
m = m_pullup(m, sizeof(struct ether_header));
if (m == NULL) {
ic->ic_stats.is_tx_nombuf++;
goto bad;
}
}
memcpy(&eh, mtod(m, caddr_t), sizeof(struct ether_header));
ni = ieee80211_find_txnode(ic, eh.ether_dhost);
if (ni == NULL) {
IEEE80211_DPRINTF(("%s: no node for dst %s, discard frame\n",
__func__, ether_sprintf(eh.ether_dhost)));
ic->ic_stats.is_tx_nonode++;
goto bad;
}
ni->ni_inact = 0;
m_adj(m, sizeof(struct ether_header) - sizeof(struct llc));
llc = mtod(m, struct llc *);
llc->llc_dsap = 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;
llc->llc_snap.ether_type = eh.ether_type;
M_PREPEND(m, sizeof(struct ieee80211_frame), M_DONTWAIT);
if (m == NULL) {
ic->ic_stats.is_tx_nombuf++;
goto bad;
}
wh = mtod(m, struct ieee80211_frame *);
wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_DATA;
*(u_int16_t *)wh->i_dur = 0;
*(u_int16_t *)wh->i_seq =
htole16(ni->ni_txseq << IEEE80211_SEQ_SEQ_SHIFT);
ni->ni_txseq++;
switch (ic->ic_opmode) {
case IEEE80211_M_STA:
wh->i_fc[1] = IEEE80211_FC1_DIR_TODS;
IEEE80211_ADDR_COPY(wh->i_addr1, ni->ni_bssid);
IEEE80211_ADDR_COPY(wh->i_addr2, eh.ether_shost);
IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_dhost);
break;
case IEEE80211_M_IBSS:
case IEEE80211_M_AHDEMO:
wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
IEEE80211_ADDR_COPY(wh->i_addr2, eh.ether_shost);
IEEE80211_ADDR_COPY(wh->i_addr3, ni->ni_bssid);
break;
case IEEE80211_M_HOSTAP:
wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
IEEE80211_ADDR_COPY(wh->i_addr2, ni->ni_bssid);
IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_shost);
break;
case IEEE80211_M_MONITOR:
goto bad;
}
*pni = ni;
return m;
bad:
if (m != NULL)
m_freem(m);
if (ni && ni != ic->ic_bss)
ieee80211_free_node(ic, ni);
*pni = NULL;
return NULL;
}
/*
* Add a supported rates element id to a frame.
*/
u_int8_t *
ieee80211_add_rates(u_int8_t *frm, const struct ieee80211_rateset *rs)
{
int nrates;
*frm++ = IEEE80211_ELEMID_RATES;
nrates = rs->rs_nrates;
if (nrates > IEEE80211_RATE_SIZE)
nrates = IEEE80211_RATE_SIZE;
*frm++ = nrates;
memcpy(frm, rs->rs_rates, nrates);
return frm + nrates;
}
/*
* Add an extended supported rates element id to a frame.
*/
u_int8_t *
ieee80211_add_xrates(u_int8_t *frm, const struct ieee80211_rateset *rs)
{
/*
* Add an extended supported rates element if operating in 11g mode.
*/
if (rs->rs_nrates > IEEE80211_RATE_SIZE) {
int nrates = rs->rs_nrates - IEEE80211_RATE_SIZE;
*frm++ = IEEE80211_ELEMID_XRATES;
*frm++ = nrates;
memcpy(frm, rs->rs_rates + IEEE80211_RATE_SIZE, nrates);
frm += nrates;
}
return frm;
}
/*
* Add an ssid elemet to a frame.
*/
static u_int8_t *
ieee80211_add_ssid(u_int8_t *frm, const u_int8_t *ssid, u_int len)
{
*frm++ = IEEE80211_ELEMID_SSID;
*frm++ = len;
memcpy(frm, ssid, len);
return frm + len;
}
static struct mbuf *
ieee80211_getmbuf(int flags, int type, u_int pktlen)
{
struct mbuf *m;
KASSERT(pktlen <= MCLBYTES, ("802.11 packet too large: %u", pktlen));
if (pktlen <= MHLEN)
MGETHDR(m, flags, type);
else
m = m_getcl(flags, type, M_PKTHDR);
return m;
}
/*
* Send a management frame. The node is for the destination (or ic_bss
* when in station mode). Nodes other than ic_bss have their reference
* count bumped to reflect our use for an indeterminant time.
*/
int
ieee80211_send_mgmt(struct ieee80211com *ic, struct ieee80211_node *ni,
int type, int arg)
{
#define senderr(_x, _v) do { ic->ic_stats._v++; ret = _x; goto bad; } while (0)
struct ifnet *ifp = &ic->ic_if;
struct mbuf *m;
u_int8_t *frm;
enum ieee80211_phymode mode;
u_int16_t capinfo;
int ret, timer;
KASSERT(ni != NULL, ("null node"));
/*
* Hold a reference on the node so it doesn't go away until after
* the xmit is complete all the way in the driver. On error we
* will remove our reference.
*/
if (ni != ic->ic_bss)
ieee80211_ref_node(ni);
timer = 0;
switch (type) {
case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
/*
* prreq frame format
* [tlv] ssid
* [tlv] supported rates
* [tlv] extended supported rates
*/
m = ieee80211_getmbuf(M_DONTWAIT, MT_DATA,
2 + ic->ic_des_esslen
+ 2 + IEEE80211_RATE_SIZE
+ 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE));
if (m == NULL)
senderr(ENOMEM, is_tx_nombuf);
m->m_data += sizeof(struct ieee80211_frame);
frm = mtod(m, u_int8_t *);
frm = ieee80211_add_ssid(frm, ic->ic_des_essid, ic->ic_des_esslen);
mode = ieee80211_chan2mode(ic, ni->ni_chan);
frm = ieee80211_add_rates(frm, &ic->ic_sup_rates[mode]);
frm = ieee80211_add_xrates(frm, &ic->ic_sup_rates[mode]);
m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
timer = IEEE80211_TRANS_WAIT;
break;
case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
/*
* probe response frame format
* [8] time stamp
* [2] beacon interval
* [2] cabability information
* [tlv] ssid
* [tlv] supported rates
* [tlv] parameter set (FH/DS)
* [tlv] parameter set (IBSS)
* [tlv] extended supported rates
*/
m = ieee80211_getmbuf(M_DONTWAIT, MT_DATA,
8 + 2 + 2 + 2
+ 2 + ni->ni_esslen
+ 2 + IEEE80211_RATE_SIZE
+ (ic->ic_phytype == IEEE80211_T_FH ? 7 : 3)
+ 6
+ 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE));
if (m == NULL)
senderr(ENOMEM, is_tx_nombuf);
m->m_data += sizeof(struct ieee80211_frame);
frm = mtod(m, u_int8_t *);
memset(frm, 0, 8); /* timestamp should be filled later */
frm += 8;
*(u_int16_t *)frm = htole16(ic->ic_bss->ni_intval);
frm += 2;
if (ic->ic_opmode == IEEE80211_M_IBSS)
capinfo = IEEE80211_CAPINFO_IBSS;
else
capinfo = IEEE80211_CAPINFO_ESS;
if (ic->ic_flags & IEEE80211_F_WEPON)
capinfo |= IEEE80211_CAPINFO_PRIVACY;
if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
IEEE80211_IS_CHAN_2GHZ(ni->ni_chan))
capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
*(u_int16_t *)frm = htole16(capinfo);
frm += 2;
frm = ieee80211_add_ssid(frm, ic->ic_bss->ni_essid,
ic->ic_bss->ni_esslen);
frm = ieee80211_add_rates(frm, &ic->ic_bss->ni_rates);
if (ic->ic_phytype == IEEE80211_T_FH) {
*frm++ = IEEE80211_ELEMID_FHPARMS;
*frm++ = 5;
*frm++ = ni->ni_fhdwell & 0x00ff;
*frm++ = (ni->ni_fhdwell >> 8) & 0x00ff;
*frm++ = IEEE80211_FH_CHANSET(
ieee80211_chan2ieee(ic, ni->ni_chan));
*frm++ = IEEE80211_FH_CHANPAT(
ieee80211_chan2ieee(ic, ni->ni_chan));
*frm++ = ni->ni_fhindex;
} else {
*frm++ = IEEE80211_ELEMID_DSPARMS;
*frm++ = 1;
*frm++ = ieee80211_chan2ieee(ic, ni->ni_chan);
}
if (ic->ic_opmode == IEEE80211_M_IBSS) {
*frm++ = IEEE80211_ELEMID_IBSSPARMS;
*frm++ = 2;
*frm++ = 0; *frm++ = 0; /* TODO: ATIM window */
} else { /* IEEE80211_M_HOSTAP */
/* TODO: TIM */
*frm++ = IEEE80211_ELEMID_TIM;
*frm++ = 4; /* length */
*frm++ = 0; /* DTIM count */
*frm++ = 1; /* DTIM period */
*frm++ = 0; /* bitmap control */
*frm++ = 0; /* Partial Virtual Bitmap (variable length) */
}
frm = ieee80211_add_xrates(frm, &ic->ic_bss->ni_rates);
m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
break;
case IEEE80211_FC0_SUBTYPE_AUTH:
MGETHDR(m, M_DONTWAIT, MT_DATA);
if (m == NULL)
senderr(ENOMEM, is_tx_nombuf);
MH_ALIGN(m, 2 * 3);
m->m_pkthdr.len = m->m_len = 6;
frm = mtod(m, u_int8_t *);
/* TODO: shared key auth */
((u_int16_t *)frm)[0] = htole16(IEEE80211_AUTH_ALG_OPEN);
((u_int16_t *)frm)[1] = htole16(arg); /* sequence number */
((u_int16_t *)frm)[2] = 0; /* status */
if (ic->ic_opmode == IEEE80211_M_STA)
timer = IEEE80211_TRANS_WAIT;
break;
case IEEE80211_FC0_SUBTYPE_DEAUTH:
if (ifp->if_flags & IFF_DEBUG)
if_printf(ifp, "station %s deauthenticate (reason %d)\n",
ether_sprintf(ni->ni_macaddr), arg);
MGETHDR(m, M_DONTWAIT, MT_DATA);
if (m == NULL)
senderr(ENOMEM, is_tx_nombuf);
MH_ALIGN(m, 2);
m->m_pkthdr.len = m->m_len = 2;
*mtod(m, u_int16_t *) = htole16(arg); /* reason */
break;
case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
/*
* asreq frame format
* [2] capability information
* [2] listen interval
* [6*] current AP address (reassoc only)
* [tlv] ssid
* [tlv] supported rates
* [tlv] extended supported rates
*/
m = ieee80211_getmbuf(M_DONTWAIT, MT_DATA,
sizeof(capinfo)
+ sizeof(u_int16_t)
+ IEEE80211_ADDR_LEN
+ 2 + ni->ni_esslen
+ 2 + IEEE80211_RATE_SIZE
+ 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE));
if (m == NULL)
senderr(ENOMEM, is_tx_nombuf);
m->m_data += sizeof(struct ieee80211_frame);
frm = mtod(m, u_int8_t *);
capinfo = 0;
if (ic->ic_opmode == IEEE80211_M_IBSS)
capinfo |= IEEE80211_CAPINFO_IBSS;
else /* IEEE80211_M_STA */
capinfo |= IEEE80211_CAPINFO_ESS;
if (ic->ic_flags & IEEE80211_F_WEPON)
capinfo |= IEEE80211_CAPINFO_PRIVACY;
/*
* NB: Some 11a AP's reject the request when
* short premable is set.
*/
if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
IEEE80211_IS_CHAN_2GHZ(ni->ni_chan))
capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
if (ic->ic_flags & IEEE80211_F_SHSLOT)
capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
*(u_int16_t *)frm = htole16(capinfo);
frm += 2;
*(u_int16_t *)frm = htole16(ic->ic_lintval);
frm += 2;
if (type == IEEE80211_FC0_SUBTYPE_REASSOC_REQ) {
IEEE80211_ADDR_COPY(frm, ic->ic_bss->ni_bssid);
frm += IEEE80211_ADDR_LEN;
}
frm = ieee80211_add_ssid(frm, ni->ni_essid, ni->ni_esslen);
frm = ieee80211_add_rates(frm, &ni->ni_rates);
frm = ieee80211_add_xrates(frm, &ni->ni_rates);
m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
timer = IEEE80211_TRANS_WAIT;
break;
case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
/*
* asreq frame format
* [2] capability information
* [2] status
* [2] association ID
* [tlv] supported rates
* [tlv] extended supported rates
*/
m = ieee80211_getmbuf(M_DONTWAIT, MT_DATA,
sizeof(capinfo)
+ sizeof(u_int16_t)
+ sizeof(u_int16_t)
+ 2 + IEEE80211_RATE_SIZE
+ 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE));
if (m == NULL)
senderr(ENOMEM, is_tx_nombuf);
m->m_data += sizeof(struct ieee80211_frame);
frm = mtod(m, u_int8_t *);
capinfo = IEEE80211_CAPINFO_ESS;
if (ic->ic_flags & IEEE80211_F_WEPON)
capinfo |= IEEE80211_CAPINFO_PRIVACY;
if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
IEEE80211_IS_CHAN_2GHZ(ni->ni_chan))
capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
*(u_int16_t *)frm = htole16(capinfo);
frm += 2;
*(u_int16_t *)frm = htole16(arg); /* status */
frm += 2;
if (arg == IEEE80211_STATUS_SUCCESS)
*(u_int16_t *)frm = htole16(ni->ni_associd);
frm += 2;
frm = ieee80211_add_rates(frm, &ni->ni_rates);
frm = ieee80211_add_xrates(frm, &ni->ni_rates);
m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
break;
case IEEE80211_FC0_SUBTYPE_DISASSOC:
if (ifp->if_flags & IFF_DEBUG)
if_printf(ifp, "station %s disassociate (reason %d)\n",
ether_sprintf(ni->ni_macaddr), arg);
MGETHDR(m, M_DONTWAIT, MT_DATA);
if (m == NULL)
senderr(ENOMEM, is_tx_nombuf);
MH_ALIGN(m, 2);
m->m_pkthdr.len = m->m_len = 2;
*mtod(m, u_int16_t *) = htole16(arg); /* reason */
break;
default:
IEEE80211_DPRINTF(("%s: invalid mgmt frame type %u\n",
__func__, type));
senderr(EINVAL, is_tx_unknownmgt);
/* NOTREACHED */
}
ret = ieee80211_mgmt_output(ifp, ni, m, type);
if (ret == 0) {
if (timer)
ic->ic_mgt_timer = timer;
} else {
bad:
if (ni != ic->ic_bss) /* remove ref we added */
ieee80211_free_node(ic, ni);
}
return ret;
#undef senderr
}