/* $NetBSD: ieee80211_input.c,v 1.24 2004/05/31 11:12:24 dyoung Exp $ */ /* $OpenBSD: ieee80211_input.c,v 1.45 2007/07/28 11:24:06 damien Exp $ */ /*- * Copyright (c) 2001 Atsushi Onoe * Copyright (c) 2002, 2003 Sam Leffler, Errno Consulting * Copyright (c) 2007 Damien Bergamini * 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. * * 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 "bpfilter.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if NBPFILTER > 0 #include #endif #ifdef INET #include #include #endif #include #include int ieee80211_setup_rates(struct ieee80211com *, struct ieee80211_node *, const u_int8_t *, const u_int8_t *, int); void ieee80211_auth_open(struct ieee80211com *, const struct ieee80211_frame *, struct ieee80211_node *, int, u_int32_t, u_int16_t, u_int16_t); int ieee80211_parse_edca_params_body(struct ieee80211com *, const u_int8_t *); int ieee80211_parse_edca_params(struct ieee80211com *, const u_int8_t *); int ieee80211_parse_wmm_params(struct ieee80211com *, const u_int8_t *); enum ieee80211_cipher ieee80211_parse_rsn_cipher(const u_int8_t[]); enum ieee80211_akm ieee80211_parse_rsn_akm(const u_int8_t[]); int ieee80211_parse_rsn_body(struct ieee80211com *, struct ieee80211_node *, const u_int8_t *, u_int); int ieee80211_parse_rsn(struct ieee80211com *, struct ieee80211_node *, const u_int8_t *); int ieee80211_parse_wpa1(struct ieee80211com *, struct ieee80211_node *, const u_int8_t *); void ieee80211_recv_pspoll(struct ieee80211com *, struct mbuf *, int, u_int32_t); int ieee80211_do_slow_print(struct ieee80211com *, int *); void ieee80211_recv_probe_resp(struct ieee80211com *, struct mbuf *, struct ieee80211_node *, int, u_int32_t); void ieee80211_recv_probe_req(struct ieee80211com *, struct mbuf *, struct ieee80211_node *, int, u_int32_t); void ieee80211_recv_auth(struct ieee80211com *, struct mbuf *, struct ieee80211_node *, int, u_int32_t); void ieee80211_recv_assoc_req(struct ieee80211com *, struct mbuf *, struct ieee80211_node *, int, u_int32_t); void ieee80211_recv_assoc_resp(struct ieee80211com *, struct mbuf *, struct ieee80211_node *, int, u_int32_t); void ieee80211_recv_deauth(struct ieee80211com *, struct mbuf *, struct ieee80211_node *, int, u_int32_t); void ieee80211_recv_disassoc(struct ieee80211com *, struct mbuf *, struct ieee80211_node *, int, u_int32_t); void ieee80211_recv_4way_msg1(struct ieee80211com *, const struct ieee80211_eapol_key *, struct ieee80211_node *); void ieee80211_recv_4way_msg2(struct ieee80211com *, const struct ieee80211_eapol_key *, struct ieee80211_node *); void ieee80211_recv_4way_msg3(struct ieee80211com *, const struct ieee80211_eapol_key *, struct ieee80211_node *); void ieee80211_recv_4way_msg4(struct ieee80211com *, const struct ieee80211_eapol_key *, struct ieee80211_node *); void ieee80211_recv_group_msg1(struct ieee80211com *, const struct ieee80211_eapol_key *, struct ieee80211_node *); void ieee80211_recv_group_msg2(struct ieee80211com *, const struct ieee80211_eapol_key *, struct ieee80211_node *); void ieee80211_recv_eapol_key_req(struct ieee80211com *, const struct ieee80211_eapol_key *, struct ieee80211_node *); /* * 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 error, hdrlen, len; u_int8_t dir, type, subtype; u_int16_t orxseq, nrxseq; if (ni == NULL) panic("null mode"); /* 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; } /* * In monitor mode, send everything directly to bpf. * XXX may want to include the CRC */ if (ic->ic_opmode == IEEE80211_M_MONITOR) goto out; /* do not process frames w/o i_addr2 any further */ if (m->m_pkthdr.len < sizeof(struct ieee80211_frame_min)) { IEEE80211_DPRINTF2(("%s: frame too short (1), len %u\n", __func__, m->m_pkthdr.len)); ic->ic_stats.is_rx_tooshort++; goto out; } wh = mtod(m, struct ieee80211_frame *); if ((wh->i_fc[0] & IEEE80211_FC0_VERSION_MASK) != IEEE80211_FC0_VERSION_0) { IEEE80211_DPRINTF(("%s: packet with wrong version: %x\n", __func__, 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)) { IEEE80211_DPRINTF2(("%s: frame too short (2), len %u\n", __func__, m->m_pkthdr.len)); ic->ic_stats.is_rx_tooshort++; goto out; } if (ic->ic_state != IEEE80211_S_SCAN) { ni->ni_rssi = rssi; ni->ni_rstamp = rstamp; if (type == IEEE80211_FC0_TYPE_DATA && (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_QOS)) { struct ieee80211_qosframe *qwh = (struct ieee80211_qosframe *)wh; int tid = qwh->i_qos[0] & IEEE80211_QOS_TID; orxseq = ni->ni_qos_rxseqs[tid]; nrxseq = ni->ni_qos_rxseqs[tid] = letoh16(*(u_int16_t *)qwh->i_seq) >> IEEE80211_SEQ_SEQ_SHIFT; } else { orxseq = ni->ni_rxseq; nrxseq = ni->ni_rxseq = letoh16(*(u_int16_t *)wh->i_seq) >> IEEE80211_SEQ_SEQ_SHIFT; } /* TODO: fragment */ if ((wh->i_fc[1] & IEEE80211_FC1_RETRY) && orxseq == nrxseq) { /* duplicate, silently discarded */ ic->ic_stats.is_rx_dup++; /* XXX per-station stat */ goto out; } ni->ni_inact = 0; } if (ic->ic_set_tim != NULL && (wh->i_fc[1] & IEEE80211_FC1_PWR_MGT) && ni->ni_pwrsave == 0) { /* turn on power save mode */ if (ifp->if_flags & IFF_DEBUG) printf("%s: power save mode on for %s\n", ifp->if_xname, ether_sprintf(wh->i_addr2)); ni->ni_pwrsave = IEEE80211_PS_SLEEP; } if (ic->ic_set_tim != NULL && !(wh->i_fc[1] & IEEE80211_FC1_PWR_MGT) && ni->ni_pwrsave != 0) { /* turn off power save mode, dequeue stored packets */ ni->ni_pwrsave = 0; (*ic->ic_set_tim)(ic, ni->ni_associd, 0); if (ifp->if_flags & IFF_DEBUG) printf("%s: power save mode off for %s\n", ifp->if_xname, ether_sprintf(wh->i_addr2)); while (!IF_IS_EMPTY(&ni->ni_savedq)) { struct mbuf *m; IF_DEQUEUE(&ni->ni_savedq, m); IF_ENQUEUE(&ic->ic_pwrsaveq, m); (*ifp->if_start)(ifp); } } 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 (ic->ic_state != IEEE80211_S_SCAN && !IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_bssid)) { /* Source address is not our BSS. */ IEEE80211_DPRINTF( ("%s: discard frame from SA %s\n", __func__, ether_sprintf(wh->i_addr2))); ic->ic_stats.is_rx_wrongbss++; 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; } if (ic->ic_state != IEEE80211_S_SCAN && !IEEE80211_ADDR_EQ(wh->i_addr3, ic->ic_bss->ni_bssid) && !IEEE80211_ADDR_EQ(wh->i_addr3, etherbroadcastaddr)) { /* Destination is not our BSS or broadcast. */ IEEE80211_DPRINTF2( ("%s: discard data frame to DA %s\n", __func__, ether_sprintf(wh->i_addr3))); ic->ic_stats.is_rx_wrongbss++; goto out; } break; case IEEE80211_M_HOSTAP: if (dir != IEEE80211_FC1_DIR_TODS) { ic->ic_stats.is_rx_wrongdir++; goto out; } if (ic->ic_state != IEEE80211_S_SCAN && !IEEE80211_ADDR_EQ(wh->i_addr1, ic->ic_bss->ni_bssid) && !IEEE80211_ADDR_EQ(wh->i_addr1, etherbroadcastaddr)) { /* BSS is not us or broadcast. */ IEEE80211_DPRINTF2( ("%s: discard data frame to BSS %s\n", __func__, ether_sprintf(wh->i_addr1))); ic->ic_stats.is_rx_wrongbss++; 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); } ic->ic_stats.is_rx_notassoc++; goto err; } if (ni->ni_associd == 0) { IEEE80211_DPRINTF(("%s: " "data from unassoc src %s\n", __func__, ether_sprintf(wh->i_addr2))); IEEE80211_SEND_MGMT(ic, ni, IEEE80211_FC0_SUBTYPE_DISASSOC, IEEE80211_REASON_NOT_ASSOCED); ic->ic_stats.is_rx_notassoc++; goto err; } break; case IEEE80211_M_MONITOR: /* can't get there */ goto out; } if (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_QOS) hdrlen = sizeof(struct ieee80211_qosframe); else hdrlen = sizeof(struct ieee80211_frame); 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; } } #if NBPFILTER > 0 /* copy to listener after decrypt */ if (ic->ic_rawbpf) bpf_mtap(ic->ic_rawbpf, m, BPF_DIRECTION_IN); #endif m = ieee80211_decap(ifp, m, hdrlen); if (m == NULL) { IEEE80211_DPRINTF(("%s: " "decapsulation error for src %s\n", __func__, ether_sprintf(wh->i_addr2))); ic->ic_stats.is_rx_decap++; goto err; } eh = mtod(m, struct ether_header *); #if 0 if (!ni->ni_port_valid && eh->ether_type != htons(ETHERTYPE_PAE)) { IEEE80211_DPRINTF(("%s: port not valid: %s\n", __func__, ether_sprintf(wh->i_addr2))); ic->ic_stats.is_rx_unauth++; goto err; } #endif ifp->if_ipackets++; /* perform as a bridge within the AP */ m1 = NULL; if (ic->ic_opmode == IEEE80211_M_HOSTAP && (ic->ic_flags & IEEE80211_F_NOBRIDGE) == 0) { if (ETHER_IS_MULTICAST(eh->ether_dhost)) { m1 = m_copym(m, 0, M_COPYALL, 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; } } } if (m1 != NULL) { len = m1->m_pkthdr.len; IFQ_ENQUEUE(&ifp->if_snd, m1, NULL, error); if (error) ifp->if_oerrors++; else { if (m != NULL) ifp->if_omcasts++; ifp->if_obytes += len; } } } if (m != NULL) { #if NBPFILTER > 0 /* * If we forward packet into transmitter of the AP, * we don't need to duplicate for DLT_EN10MB. */ if (ifp->if_bpf && m1 == NULL) bpf_mtap(ifp->if_bpf, m, BPF_DIRECTION_IN); #endif ether_input_mbuf(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; } } 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) printf("%s: received %s from %s rssi %d mode %s\n", ifp->if_xname, ieee80211_mgt_subtype_name[subtype >> IEEE80211_FC0_SUBTYPE_SHIFT], ether_sprintf(wh->i_addr2), rssi, ieee80211_phymode_name[ieee80211_chan2mode(ic, ic->ic_bss->ni_chan)]); } #if NBPFILTER > 0 if (ic->ic_rawbpf) bpf_mtap(ic->ic_rawbpf, m, BPF_DIRECTION_IN); /* * Drop mbuf if it was filtered by bpf. Normally, this is * done in ether_input() but IEEE 802.11 management frames * are a special case. */ if (m->m_flags & M_FILDROP) { m_freem(m); return; } #endif (*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++; if (ic->ic_opmode != IEEE80211_M_HOSTAP) goto out; subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK; if (subtype == IEEE80211_FC0_SUBTYPE_PS_POLL) { /* XXX statistic */ /* Dump out a single packet from the host */ if (ifp->if_flags & IFF_DEBUG) printf("%s: got power save probe from %s\n", ifp->if_xname, ether_sprintf(wh->i_addr2)); ieee80211_recv_pspoll(ic, m, rssi, rstamp); } goto out; default: IEEE80211_DPRINTF(("%s: bad packet type %x\n", __func__, type)); /* should not come here */ break; } err: ifp->if_ierrors++; out: if (m != NULL) { #if NBPFILTER > 0 if (ic->ic_rawbpf) bpf_mtap(ic->ic_rawbpf, m, BPF_DIRECTION_IN); #endif m_freem(m); } } struct mbuf * ieee80211_decap(struct ifnet *ifp, struct mbuf *m, int hdrlen) { struct ieee80211_frame wh; struct ether_header *eh; struct llc *llc; if (m->m_len < hdrlen + sizeof(*llc)) { m = m_pullup(m, hdrlen + sizeof(*llc)); if (m == NULL) return NULL; } memcpy(&wh, mtod(m, caddr_t), sizeof(wh)); llc = (struct llc *)(mtod(m, caddr_t) + hdrlen); 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, hdrlen + sizeof(struct llc) - sizeof(*eh)); llc = NULL; } else { m_adj(m, hdrlen - 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: discard DS to DS frame\n", __func__)); m_freem(m); return NULL; } 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_DUP_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; } 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. */ int ieee80211_setup_rates(struct ieee80211com *ic, struct ieee80211_node *ni, const u_int8_t *rates, const 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[ \ (wh->i_fc[0] & \ IEEE80211_FC0_SUBTYPE_MASK) >> \ 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[(wh->i_fc[0] & \ IEEE80211_FC0_SUBTYPE_MASK) >> \ IEEE80211_FC0_SUBTYPE_SHIFT], \ ether_sprintf((u_int8_t *)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[(wh->i_fc[0] & \ IEEE80211_FC0_SUBTYPE_MASK) >> \ IEEE80211_FC0_SUBTYPE_SHIFT], \ ether_sprintf((u_int8_t *)wh->i_addr2))); \ ic->ic_stats.is_rx_elem_toosmall++; \ return; \ } \ } while (0) #ifdef IEEE80211_DEBUG void ieee80211_ssid_mismatch(struct ieee80211com *, const char *, const u_int8_t[IEEE80211_ADDR_LEN], const u_int8_t *); void ieee80211_ssid_mismatch(struct ieee80211com *ic, const char *tag, const u_int8_t mac[IEEE80211_ADDR_LEN], const u_int8_t *ssid) { printf("[%s] %s req ssid mismatch: ", ether_sprintf((u_int8_t *)mac), tag); ieee80211_print_essid(ssid + 2, ssid[1]); printf("\n"); } #define IEEE80211_VERIFY_SSID(_ni, _ssid, _packet_type) do { \ if ((_ssid)[1] != 0 && \ ((_ssid)[1] != (_ni)->ni_esslen || \ memcmp((_ssid) + 2, (_ni)->ni_essid, (_ssid)[1]) != 0)) { \ if (ieee80211_debug) \ ieee80211_ssid_mismatch(ic, _packet_type, \ wh->i_addr2, _ssid); \ ic->ic_stats.is_rx_ssidmismatch++; \ return; \ } \ } while (0) #else /* !IEEE80211_DEBUG */ #define IEEE80211_VERIFY_SSID(_ni, _ssid, _packet_type) do { \ if ((_ssid)[1] != 0 && \ ((_ssid)[1] != (_ni)->ni_esslen || \ memcmp((_ssid) + 2, (_ni)->ni_essid, (_ssid)[1]) != 0)) { \ ic->ic_stats.is_rx_ssidmismatch++; \ return; \ } \ } while (0) #endif /* !IEEE80211_DEBUG */ void ieee80211_auth_open(struct ieee80211com *ic, const struct ieee80211_frame *wh, struct ieee80211_node *ni, int rssi, u_int32_t rstamp, u_int16_t seq, u_int16_t status) { struct ifnet *ifp = &ic->ic_if; switch (ic->ic_opmode) { case IEEE80211_M_IBSS: if (ic->ic_state != IEEE80211_S_RUN || seq != IEEE80211_AUTH_OPEN_REQUEST) { IEEE80211_DPRINTF(("%s: discard auth from %s; " "state %u, seq %u\n", __func__, ether_sprintf((u_int8_t *)wh->i_addr2), ic->ic_state, seq)); ic->ic_stats.is_rx_bad_auth++; return; } 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 != IEEE80211_AUTH_OPEN_REQUEST) { IEEE80211_DPRINTF(("%s: discard auth from %s; " "state %u, seq %u\n", __func__, ether_sprintf((u_int8_t *)wh->i_addr2), ic->ic_state, seq)); ic->ic_stats.is_rx_bad_auth++; return; } 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; } IEEE80211_SEND_MGMT(ic, ni, IEEE80211_FC0_SUBTYPE_AUTH, seq + 1); if (ifp->if_flags & IFF_DEBUG) printf("%s: station %s %s authenticated (open)\n", ifp->if_xname, ether_sprintf((u_int8_t *)ni->ni_macaddr), ni->ni_state != IEEE80211_STA_CACHE ? "newly" : "already"); ieee80211_node_newstate(ni, IEEE80211_STA_AUTH); break; case IEEE80211_M_STA: if (ic->ic_state != IEEE80211_S_AUTH || seq != IEEE80211_AUTH_OPEN_RESPONSE) { ic->ic_stats.is_rx_bad_auth++; IEEE80211_DPRINTF(("%s: discard auth from %s; " "state %u, seq %u\n", __func__, ether_sprintf((u_int8_t *)wh->i_addr2), ic->ic_state, seq)); return; } if (status != 0) { if (ifp->if_flags & IFF_DEBUG) printf("%s: open authentication failed " "(reason %d) for %s\n", ifp->if_xname, status, ether_sprintf((u_int8_t *)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; } } /* unaligned little endian access */ #define LE_READ_2(p) \ ((u_int16_t) \ ((((const u_int8_t *)(p))[0]) | \ (((const u_int8_t *)(p))[1] << 8))) #define LE_READ_4(p) \ ((u_int32_t) \ ((((const u_int8_t *)(p))[0]) | \ (((const u_int8_t *)(p))[1] << 8) | \ (((const u_int8_t *)(p))[2] << 16) | \ (((const u_int8_t *)(p))[3] << 24))) /* * Parse an EDCA Parameter Set element (see 7.3.2.27). */ int ieee80211_parse_edca_params_body(struct ieee80211com *ic, const u_int8_t *frm) { u_int updtcount; int aci; /* * Check if EDCA parameters have changed XXX if we miss more than * 15 consecutive beacons, we might not detect changes to EDCA * parameters due to wraparound of the 4-bit Update Count field. */ updtcount = frm[0] & 0xf; if (updtcount == ic->ic_edca_updtcount) return 0; /* no changes to EDCA parameters, ignore */ ic->ic_edca_updtcount = updtcount; frm += 2; /* skip QoS Info & Reserved fields */ /* parse AC Parameter Records */ for (aci = 0; aci < EDCA_NUM_AC; aci++) { struct ieee80211_edca_ac_params *ac = &ic->ic_edca_ac[aci]; ac->ac_acm = (frm[0] >> 4) & 0x1; ac->ac_aifsn = frm[0] & 0xf; ac->ac_ecwmin = frm[1] & 0xf; ac->ac_ecwmax = frm[1] >> 4; ac->ac_txoplimit = LE_READ_2(frm + 2); frm += 4; } /* give drivers a chance to update their settings */ if ((ic->ic_flags & IEEE80211_F_QOS) && ic->ic_updateedca != NULL) (*ic->ic_updateedca)(ic); return 0; } int ieee80211_parse_edca_params(struct ieee80211com *ic, const u_int8_t *frm) { /* check IE length */ if (frm[1] < 18) { IEEE80211_DPRINTF(("%s: invalid EDCA parameter set IE;" " length %u, expecting 18\n", __func__, frm[1])); ic->ic_stats.is_rx_elem_toosmall++; return IEEE80211_REASON_IE_INVALID; } return ieee80211_parse_edca_params_body(ic, frm + 2); } int ieee80211_parse_wmm_params(struct ieee80211com *ic, const u_int8_t *frm) { /* check IE length */ if (frm[1] < 24) { IEEE80211_DPRINTF(("%s: invalid WMM parameter set IE;" " length %u, expecting 24\n", __func__, frm[1])); ic->ic_stats.is_rx_elem_toosmall++; return IEEE80211_REASON_IE_INVALID; } return ieee80211_parse_edca_params_body(ic, frm + 8); } enum ieee80211_cipher ieee80211_parse_rsn_cipher(const u_int8_t selector[4]) { /* from IEEE Std 802.11i-2004 - Table 20da */ if (memcmp(selector, MICROSOFT_OUI, 3) == 0 || /* WPA1 */ memcmp(selector, IEEE80211_OUI, 3) == 0) { /* RSN (aka WPA2) */ switch (selector[3]) { case 0: /* use group cipher suite */ return IEEE80211_CIPHER_USEGROUP; case 1: /* WEP-40 */ return IEEE80211_CIPHER_WEP40; case 2: /* TKIP */ return IEEE80211_CIPHER_TKIP; case 3: /* CCMP (RSNA default) */ return IEEE80211_CIPHER_CCMP; case 5: /* WEP-104 */ return IEEE80211_CIPHER_WEP104; } } return IEEE80211_CIPHER_NONE; /* ignore unknown ciphers */ } enum ieee80211_akm ieee80211_parse_rsn_akm(const u_int8_t selector[4]) { /* from IEEE Std 802.11i-2004 - Table 20dc */ if (memcmp(selector, MICROSOFT_OUI, 3) == 0 || /* WPA1 */ memcmp(selector, IEEE80211_OUI, 3) == 0) { /* RSN (aka WPA2) */ switch (selector[3]) { case 1: /* IEEE 802.1X (RSNA default) */ return IEEE80211_AKM_IEEE8021X; case 2: /* PSK */ return IEEE80211_AKM_PSK; } } return IEEE80211_AKM_NONE; /* ignore unknown AKMs */ } /* * Parse an RSN element (see 7.3.2.25). */ int ieee80211_parse_rsn_body(struct ieee80211com *ic, struct ieee80211_node *ni, const u_int8_t *frm, u_int len) { const u_int8_t *efrm; u_int16_t m, n, s; u_int16_t rsncaps; enum ieee80211_cipher group_cipher; u_int akmset, pairwise_cipherset; efrm = frm + len; /* check Version field */ if (LE_READ_2(frm) != 1) return IEEE80211_REASON_RSN_IE_VER_UNSUP; frm += 2; /* all fields after the Version field are optional */ /* if Cipher Suite missing, default to CCMP */ ni->ni_group_cipher = IEEE80211_CIPHER_CCMP; ni->ni_pairwise_cipherset = IEEE80211_CIPHER_CCMP; /* if AKM Suite missing, default to 802.1X */ ni->ni_akmset = IEEE80211_AKM_IEEE8021X; /* read Group Cipher Suite field */ if (frm + 4 > efrm) return 0; group_cipher = ieee80211_parse_rsn_cipher(frm); if (group_cipher == IEEE80211_CIPHER_USEGROUP) return IEEE80211_REASON_BAD_GROUP_CIPHER; frm += 4; /* read Pairwise Cipher Suite Count field */ if (frm + 2 > efrm) return 0; m = LE_READ_2(frm); frm += 2; /* read Pairwise Cipher Suite List */ if (frm + m * 4 > efrm) return IEEE80211_REASON_IE_INVALID; pairwise_cipherset = IEEE80211_CIPHER_NONE; while (m-- > 0) { pairwise_cipherset |= ieee80211_parse_rsn_cipher(frm); frm += 4; } if (pairwise_cipherset & IEEE80211_CIPHER_USEGROUP) { if (pairwise_cipherset != IEEE80211_CIPHER_USEGROUP) return IEEE80211_REASON_BAD_PAIRWISE_CIPHER; if (group_cipher == IEEE80211_CIPHER_CCMP) return IEEE80211_REASON_BAD_PAIRWISE_CIPHER; } /* read AKM Suite List Count field */ if (frm + 2 > efrm) return 0; n = LE_READ_2(frm); frm += 2; /* read AKM Suite List */ if (frm + n * 4 > efrm) return IEEE80211_REASON_IE_INVALID; akmset = IEEE80211_AKM_NONE; while (n-- > 0) { akmset |= ieee80211_parse_rsn_akm(frm); frm += 4; } /* read RSN Capabilities field */ if (frm + 2 > efrm) return 0; rsncaps = LE_READ_2(frm); frm += 2; /* read PMKID Count field */ if (frm + 2 > efrm) return 0; s = LE_READ_2(frm); frm += 2; /* read PMKID List */ if (frm + s * IEEE80211_PMKID_LEN > efrm) return IEEE80211_REASON_IE_INVALID; while (s-- > 0) { /* ignore PMKIDs for now */ frm += IEEE80211_PMKID_LEN; } ni->ni_group_cipher = group_cipher; ni->ni_pairwise_cipherset = pairwise_cipherset; ni->ni_akmset = akmset; ni->ni_rsncaps = rsncaps; return 0; } int ieee80211_parse_rsn(struct ieee80211com *ic, struct ieee80211_node *ni, const u_int8_t *frm) { /* check IE length */ if (frm[1] < 2) { IEEE80211_DPRINTF(("%s: invalid RSN/WPA2 IE;" " length %u, expecting at least 2\n", __func__, frm[1])); ic->ic_stats.is_rx_elem_toosmall++; return IEEE80211_REASON_IE_INVALID; } return ieee80211_parse_rsn_body(ic, ni, frm + 2, frm[1] - 2); } int ieee80211_parse_wpa1(struct ieee80211com *ic, struct ieee80211_node *ni, const u_int8_t *frm) { /* check IE length */ if (frm[1] < 6) { IEEE80211_DPRINTF(("%s: invalid WPA1 IE;" " length %u, expecting at least 6\n", __func__, frm[1])); ic->ic_stats.is_rx_elem_toosmall++; return IEEE80211_REASON_IE_INVALID; } return ieee80211_parse_rsn_body(ic, ni, frm + 6, frm[1] - 6); } /*- * Beacon/Probe response frame format: * [8] Timestamp * [2] Beacon interval * [2] Capability * [tlv] Service Set Identifier (SSID) * [tlv] Supported rates * [tlv*] Frequency-Hopping (FH) Parameter Set * [tlv*] DS Parameter Set (802.11g) * [tlv] ERP Information (802.11g) * [tlv] Extended Supported Rates (802.11g) * [tlv] RSN (802.11i) * [tlv] EDCA Parameter Set (802.11e) * [tlv] QoS Capability (Beacon only, 802.11e) */ void ieee80211_recv_probe_resp(struct ieee80211com *ic, struct mbuf *m0, struct ieee80211_node *ni, int rssi, u_int32_t rstamp) { #define ISPROBE(_wh) (((_wh)->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == \ IEEE80211_FC0_SUBTYPE_PROBE_RESP) const struct ieee80211_frame *wh; const u_int8_t *frm, *efrm; const u_int8_t *tstamp, *ssid, *rates, *xrates, *edca, *wmm; const u_int8_t *rsn, *wpa; u_int16_t capinfo, bintval, fhdwell; u_int8_t chan, bchan, fhindex, erp; int is_new; /* * We process beacon/probe response frames for: * o station mode: to collect state * updates such as 802.11g slot time and for passive * scanning of APs * o adhoc mode: to discover neighbors * o hostap mode: for passive scanning of neighbor APs * o when scanning * In other words, in all modes other than monitor (which * does not process incoming packets) and adhoc-demo (which * does not use management frames at all). */ #ifdef DIAGNOSTIC if (ic->ic_opmode != IEEE80211_M_STA && ic->ic_opmode != IEEE80211_M_IBSS && ic->ic_opmode != IEEE80211_M_HOSTAP && ic->ic_state != IEEE80211_S_SCAN) { panic("%s: impossible operating mode", __func__); } #endif wh = mtod(m0, struct ieee80211_frame *); frm = (const u_int8_t *)&wh[1]; efrm = mtod(m0, u_int8_t *) + m0->m_len; IEEE80211_VERIFY_LENGTH(efrm - frm, 12); tstamp = frm; frm += 8; bintval = LE_READ_2(frm); frm += 2; capinfo = LE_READ_2(frm); frm += 2; ssid = rates = xrates = edca = wmm = rsn = wpa = NULL; bchan = ieee80211_chan2ieee(ic, ic->ic_bss->ni_chan); chan = bchan; fhdwell = 0; fhindex = 0; erp = 0; while (frm + 2 <= efrm) { if (frm + 2 + frm[1] > efrm) { ic->ic_stats.is_rx_elem_toosmall++; return; } switch (frm[0]) { case IEEE80211_ELEMID_SSID: ssid = frm; break; case IEEE80211_ELEMID_RATES: rates = frm; break; case IEEE80211_ELEMID_FHPARMS: if (ic->ic_phytype != IEEE80211_T_FH) break; if (frm[1] < 5) { ic->ic_stats.is_rx_elem_toosmall++; break; } fhdwell = LE_READ_2(frm + 2); chan = IEEE80211_FH_CHAN(frm[4], frm[5]); fhindex = frm[6]; break; case IEEE80211_ELEMID_DSPARMS: if (ic->ic_phytype == IEEE80211_T_FH) break; if (frm[1] < 1) { ic->ic_stats.is_rx_elem_toosmall++; break; } chan = frm[2]; break; case IEEE80211_ELEMID_TIM: break; case IEEE80211_ELEMID_IBSSPARMS: break; case IEEE80211_ELEMID_XRATES: xrates = frm; break; case IEEE80211_ELEMID_ERP: if (frm[1] < 1) { ic->ic_stats.is_rx_elem_toosmall++; break; } erp = frm[2]; break; case IEEE80211_ELEMID_RSN: rsn = frm; break; case IEEE80211_ELEMID_EDCAPARMS: edca = frm; break; case IEEE80211_ELEMID_QOS_CAP: break; case IEEE80211_ELEMID_VENDOR: if (frm[1] < 4) { ic->ic_stats.is_rx_elem_toosmall++; break; } if (memcmp(frm + 2, MICROSOFT_OUI, 3) == 0) { if (frm[5] == 1) wpa = frm; else if (frm[1] >= 5 && frm[5] == 2 && frm[6] == 1) wmm = frm; } 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 += 2 + frm[1]; } 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(wh) ? "probe response" : "beacon", chan)); ic->ic_stats.is_rx_badchan++; return; } if (!(ic->ic_caps & IEEE80211_C_SCANALL) && (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(wh) ? "probe response" : "beacon", bchan, chan)); ic->ic_stats.is_rx_chanmismatch++; return; } /* * Use mac, channel and rssi so we collect only the * best potential AP with the equal bssid while scanning. * Collecting all potential APs may result in bloat of * the node tree. This call will return NULL if the node * for this APs does not exist or if the new node is the * potential better one. */ if ((ni = ieee80211_find_node_for_beacon(ic, wh->i_addr2, &ic->ic_channels[chan], ssid, rssi)) != NULL) return; #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(wh) ? "probe response" : "beacon", chan, bchan); ieee80211_print_essid(ssid + 2, ssid[1]); printf(" from %s\n", ether_sprintf((u_int8_t *)wh->i_addr2)); printf("%s: caps 0x%x bintval %u erp 0x%x\n", __func__, capinfo, bintval, erp); } #endif if ((ni = ieee80211_find_node(ic, wh->i_addr2)) == NULL) { ni = ieee80211_alloc_node(ic, wh->i_addr2); if (ni == NULL) return; is_new = 1; } else is_new = 0; /* * When operating in station mode, check for state updates * while we're associated. We consider only 11g stuff right * now. */ if (ic->ic_opmode == IEEE80211_M_STA && ic->ic_state == IEEE80211_S_ASSOC && ni->ni_state == IEEE80211_STA_BSS) { /* * Check if protection mode has changed since last * beacon. */ if (ni->ni_erp != erp) { IEEE80211_DPRINTF(( "[%s] erp change: was 0x%x, now 0x%x\n", ether_sprintf((u_int8_t *)wh->i_addr2), ni->ni_erp, erp)); if (ic->ic_curmode == IEEE80211_MODE_11G && (erp & IEEE80211_ERP_USE_PROTECTION)) ic->ic_flags |= IEEE80211_F_USEPROT; else ic->ic_flags &= ~IEEE80211_F_USEPROT; ic->ic_bss->ni_erp = erp; } /* * Check if AP short slot time setting has changed * since last beacon and give the driver a chance to * update the hardware. */ if ((ni->ni_capinfo ^ capinfo) & IEEE80211_CAPINFO_SHORT_SLOTTIME) { ieee80211_set_shortslottime(ic, ic->ic_curmode == IEEE80211_MODE_11A || (capinfo & IEEE80211_CAPINFO_SHORT_SLOTTIME)); } } if (ni->ni_flags & IEEE80211_NODE_QOS) { if (edca != NULL) ieee80211_parse_edca_params(ic, edca); else if (wmm != NULL) ieee80211_parse_wmm_params(ic, edca); } if (ssid[1] != 0 && ni->ni_esslen == 0) { /* * 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 = bintval; ni->ni_capinfo = 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); /* * When scanning we record results (nodes) with a zero * refcnt. Otherwise we want to hold the reference for * ibss neighbors so the nodes don't get released prematurely. * Anything else can be discarded (XXX and should be handled * above so we don't do so much work). */ if (ic->ic_opmode == IEEE80211_M_IBSS || (is_new && ISPROBE(wh))) { /* * Fake an association so the driver can setup it's * private state. The rate set has been setup above; * there is no handshake as in ap/station operation. */ if (ic->ic_newassoc) (*ic->ic_newassoc)(ic, ni, 1); } #undef ISPROBE } /*- * Probe request frame format: * [tlv] SSID * [tlv] Supported rates * [tlv] Extended Supported Rates (802.11g) */ void ieee80211_recv_probe_req(struct ieee80211com *ic, struct mbuf *m0, struct ieee80211_node *ni, int rssi, u_int32_t rstamp) { const struct ieee80211_frame *wh; const u_int8_t *frm, *efrm; const u_int8_t *ssid, *rates, *xrates; u_int8_t rate; if (ic->ic_opmode == IEEE80211_M_STA || ic->ic_state != IEEE80211_S_RUN) return; wh = mtod(m0, struct ieee80211_frame *); frm = (const u_int8_t *)&wh[1]; efrm = mtod(m0, u_int8_t *) + m0->m_len; ssid = rates = xrates = NULL; while (frm + 2 <= efrm) { if (frm + 2 + frm[1] > efrm) { ic->ic_stats.is_rx_elem_toosmall++; return; } switch (frm[0]) { case IEEE80211_ELEMID_SSID: ssid = frm; break; case IEEE80211_ELEMID_RATES: rates = frm; break; case IEEE80211_ELEMID_XRATES: xrates = frm; break; } frm += 2 + frm[1]; } IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE); IEEE80211_VERIFY_ELEMENT(ssid, IEEE80211_NWID_LEN); IEEE80211_VERIFY_SSID(ic->ic_bss, ssid, "probe"); if ((ic->ic_flags & IEEE80211_F_HIDENWID) && ssid[1] == 0) { IEEE80211_DPRINTF(("%s: no ssid " "with ssid suppression enabled", __func__)); ic->ic_stats.is_rx_ssidmismatch++; return; } if (ni == ic->ic_bss) { ni = ieee80211_dup_bss(ic, wh->i_addr2); if (ni == NULL) return; IEEE80211_DPRINTF(("%s: new probe req from %s\n", __func__, ether_sprintf((u_int8_t *)wh->i_addr2))); } 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 mismatch for %s\n", __func__, ether_sprintf((u_int8_t *)wh->i_addr2))); } else { IEEE80211_SEND_MGMT(ic, ni, IEEE80211_FC0_SUBTYPE_PROBE_RESP, 0); } } /*- * Authentication frame format: * [2] Authentication algorithm number * [2] Authentication transaction sequence number * [2] Status code */ void ieee80211_recv_auth(struct ieee80211com *ic, struct mbuf *m0, struct ieee80211_node *ni, int rssi, u_int32_t rstamp) { const struct ieee80211_frame *wh; const u_int8_t *frm, *efrm; u_int16_t algo, seq, status; wh = mtod(m0, struct ieee80211_frame *); frm = (const u_int8_t *)&wh[1]; efrm = mtod(m0, u_int8_t *) + m0->m_len; IEEE80211_VERIFY_LENGTH(efrm - frm, 6); algo = LE_READ_2(frm); frm += 2; seq = LE_READ_2(frm); frm += 2; status = LE_READ_2(frm); frm += 2; IEEE80211_DPRINTF(("%s: auth %d seq %d from %s\n", __func__, algo, seq, ether_sprintf((u_int8_t *)wh->i_addr2))); if (algo == IEEE80211_AUTH_ALG_OPEN) ieee80211_auth_open(ic, wh, ni, rssi, rstamp, seq, status); else { IEEE80211_DPRINTF(("%s: unsupported authentication " "algorithm %d from %s\n", __func__, algo, ether_sprintf((u_int8_t *)wh->i_addr2))); ic->ic_stats.is_rx_auth_unsupported++; if (ic->ic_opmode == IEEE80211_M_HOSTAP) { /* XXX hack to workaround calling convention */ IEEE80211_SEND_MGMT(ic, ni, IEEE80211_FC0_SUBTYPE_AUTH, (seq+1) | (IEEE80211_STATUS_ALG<<16)); } } } /*- * (Re)Association request frame format: * [2] Capability information * [2] Listen interval * [6*] Current AP address (Reassociation only) * [tlv] SSID * [tlv] Supported rates * [tlv] Extended Supported Rates (802.11g) * [tlv] RSN (802.11i) * [tlv] QoS Capability (802.11e) */ void ieee80211_recv_assoc_req(struct ieee80211com *ic, struct mbuf *m0, struct ieee80211_node *ni, int rssi, u_int32_t rstamp) { #define ISREASSOC(_wh) (((_wh)->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == \ IEEE80211_FC0_SUBTYPE_REASSOC_REQ) const struct ieee80211_frame *wh; const u_int8_t *frm, *efrm; const u_int8_t *ssid, *rates, *xrates, *rsn, *wpa; u_int16_t capinfo, bintval; int reassoc, resp, reason = 0; u_int8_t rate; if (ic->ic_opmode != IEEE80211_M_HOSTAP || ic->ic_state != IEEE80211_S_RUN) return; wh = mtod(m0, struct ieee80211_frame *); frm = (const u_int8_t *)&wh[1]; efrm = mtod(m0, u_int8_t *) + m0->m_len; if (ISREASSOC(wh)) { reassoc = 1; resp = IEEE80211_FC0_SUBTYPE_REASSOC_RESP; } else { reassoc = 0; resp = IEEE80211_FC0_SUBTYPE_ASSOC_RESP; } 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((u_int8_t *)wh->i_addr2))); ic->ic_stats.is_rx_assoc_bss++; return; } capinfo = LE_READ_2(frm); frm += 2; bintval = LE_READ_2(frm); frm += 2; if (reassoc) frm += IEEE80211_ADDR_LEN; /* skip current AP address */ ssid = rates = xrates = rsn = wpa = NULL; while (frm + 2 <= efrm) { if (frm + 2 + frm[1] > efrm) { ic->ic_stats.is_rx_elem_toosmall++; return; } switch (frm[0]) { case IEEE80211_ELEMID_SSID: ssid = frm; break; case IEEE80211_ELEMID_RATES: rates = frm; break; case IEEE80211_ELEMID_XRATES: xrates = frm; break; case IEEE80211_ELEMID_RSN: rsn = frm; break; case IEEE80211_ELEMID_QOS_CAP: break; case IEEE80211_ELEMID_VENDOR: if (frm[1] < 4) { ic->ic_stats.is_rx_elem_toosmall++; break; } if (memcmp(frm + 2, MICROSOFT_OUI, 3) == 0) { if (frm[5] == 1) wpa = frm; } break; } frm += 2 + frm[1]; } IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE); IEEE80211_VERIFY_ELEMENT(ssid, IEEE80211_NWID_LEN); IEEE80211_VERIFY_SSID(ic->ic_bss, ssid, reassoc ? "reassoc" : "assoc"); if (ni->ni_state != IEEE80211_STA_AUTH && ni->ni_state != IEEE80211_STA_ASSOC) { IEEE80211_DPRINTF( ("%s: deny %sassoc from %s, not authenticated\n", __func__, reassoc ? "re" : "", ether_sprintf((u_int8_t *)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); } ic->ic_stats.is_rx_assoc_notauth++; return; } if (rsn != NULL) reason = ieee80211_parse_rsn(ic, ni, rsn); else if (wpa != NULL) reason = ieee80211_parse_wpa1(ic, ni, wpa); if (reason != 0) { IEEE80211_DPRINTF(("%s: invalid RSN IE for %s\n", __func__, ether_sprintf((u_int8_t *)wh->i_addr2))); IEEE80211_SEND_MGMT(ic, ni, IEEE80211_FC0_SUBTYPE_DEAUTH, reason); ieee80211_node_leave(ic, ni); ic->ic_stats.is_rx_assoc_badrsnie++; return; } if (!(capinfo & IEEE80211_CAPINFO_ESS)) { IEEE80211_DPRINTF(("%s: capinfo mismatch for %s\n", __func__, ether_sprintf((u_int8_t *)wh->i_addr2))); IEEE80211_SEND_MGMT(ic, ni, resp, IEEE80211_STATUS_CAPINFO); ieee80211_node_leave(ic, ni); ic->ic_stats.is_rx_assoc_capmismatch++; return; } 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 mismatch for %s\n", __func__, ether_sprintf((u_int8_t *)wh->i_addr2))); IEEE80211_SEND_MGMT(ic, ni, resp, IEEE80211_STATUS_BASIC_RATE); ieee80211_node_leave(ic, ni); 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; ieee80211_node_join(ic, ni, resp); #undef ISREASSOC } /*- * (Re)Association response frame format: * [2] Capability information * [2] Status code * [2] Association ID (AID) * [tlv] Supported rates * [tlv] Extended Supported Rates (802.11g) * [tlv] EDCA Parameter Set (802.11e) */ void ieee80211_recv_assoc_resp(struct ieee80211com *ic, struct mbuf *m0, struct ieee80211_node *ni, int rssi, u_int32_t rstamp) { #define ISREASSOC(_wh) (((_wh)->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == \ IEEE80211_FC0_SUBTYPE_REASSOC_RESP) struct ifnet *ifp = &ic->ic_if; const struct ieee80211_frame *wh; const u_int8_t *frm, *efrm; const u_int8_t *rates, *xrates, *edca, *wmm; u_int16_t capinfo, status, associd; u_int8_t rate; if (ic->ic_opmode != IEEE80211_M_STA || ic->ic_state != IEEE80211_S_ASSOC) { ic->ic_stats.is_rx_mgtdiscard++; return; } wh = mtod(m0, struct ieee80211_frame *); frm = (const u_int8_t *)&wh[1]; efrm = mtod(m0, u_int8_t *) + m0->m_len; IEEE80211_VERIFY_LENGTH(efrm - frm, 6); ni = ic->ic_bss; capinfo = LE_READ_2(frm); frm += 2; status = LE_READ_2(frm); frm += 2; if (status != 0) { if (ifp->if_flags & IFF_DEBUG) printf("%s: %sassociation failed (reason %d)" " for %s\n", ifp->if_xname, ISREASSOC(wh) ? "re" : "", status, ether_sprintf((u_int8_t *)wh->i_addr3)); if (ni != ic->ic_bss) ni->ni_fails++; ic->ic_stats.is_rx_auth_fail++; return; } associd = LE_READ_2(frm); frm += 2; rates = xrates = edca = wmm = NULL; while (frm + 2 <= efrm) { if (frm + 2 + frm[1] > efrm) { ic->ic_stats.is_rx_elem_toosmall++; return; } switch (frm[0]) { case IEEE80211_ELEMID_RATES: rates = frm; break; case IEEE80211_ELEMID_XRATES: xrates = frm; break; case IEEE80211_ELEMID_EDCAPARMS: edca = frm; break; case IEEE80211_ELEMID_VENDOR: if (frm[1] < 4) { ic->ic_stats.is_rx_elem_toosmall++; break; } if (memcmp(frm + 2, MICROSOFT_OUI, 3) == 0) { if (frm[1] >= 5 && frm[5] == 2 && frm[6] == 1) wmm = frm; } break; } frm += 2 + frm[1]; } IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE); 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 mismatch for %s\n", __func__, ether_sprintf((u_int8_t *)wh->i_addr2))); ic->ic_stats.is_rx_assoc_norate++; return; } ni->ni_capinfo = capinfo; ni->ni_associd = associd; if (edca != NULL || wmm != NULL) { /* force update of EDCA parameters */ ic->ic_edca_updtcount = -1; if ((edca != NULL && ieee80211_parse_edca_params(ic, edca) == 0) || (wmm != NULL && ieee80211_parse_wmm_params(ic, wmm) == 0)) ni->ni_flags |= IEEE80211_NODE_QOS; else /* for Reassociation */ ni->ni_flags &= ~IEEE80211_NODE_QOS; } /* * Configure state now that we are associated. */ if (ic->ic_curmode == IEEE80211_MODE_11A || (ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_PREAMBLE)) ic->ic_flags |= IEEE80211_F_SHPREAMBLE; else ic->ic_flags &= ~IEEE80211_F_SHPREAMBLE; ieee80211_set_shortslottime(ic, ic->ic_curmode == IEEE80211_MODE_11A || (ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_SLOTTIME)); /* * Honor ERP protection. */ if (ic->ic_curmode == IEEE80211_MODE_11G && (ni->ni_erp & IEEE80211_ERP_USE_PROTECTION)) ic->ic_flags |= IEEE80211_F_USEPROT; else ic->ic_flags &= ~IEEE80211_F_USEPROT; ieee80211_new_state(ic, IEEE80211_S_RUN, wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK); #undef ISREASSOC } /*- * Deauthentication frame format: * [2] Reason code */ void ieee80211_recv_deauth(struct ieee80211com *ic, struct mbuf *m0, struct ieee80211_node *ni, int rssi, u_int32_t rstamp) { struct ifnet *ifp = &ic->ic_if; const struct ieee80211_frame *wh; const u_int8_t *frm, *efrm; u_int16_t reason; wh = mtod(m0, struct ieee80211_frame *); frm = (const u_int8_t *)&wh[1]; efrm = mtod(m0, u_int8_t *) + m0->m_len; IEEE80211_VERIFY_LENGTH(efrm - frm, 2); reason = LE_READ_2(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) printf("%s: station %s deauthenticated " "by peer (reason %d)\n", ifp->if_xname, ether_sprintf(ni->ni_macaddr), reason); ieee80211_node_leave(ic, ni); } break; default: break; } } /*- * Disassociation frame format: * [2] Reason code */ void ieee80211_recv_disassoc(struct ieee80211com *ic, struct mbuf *m0, struct ieee80211_node *ni, int rssi, u_int32_t rstamp) { struct ifnet *ifp = &ic->ic_if; const struct ieee80211_frame *wh; const u_int8_t *frm, *efrm; u_int16_t reason; wh = mtod(m0, struct ieee80211_frame *); frm = (const u_int8_t *)&wh[1]; efrm = mtod(m0, u_int8_t *) + m0->m_len; IEEE80211_VERIFY_LENGTH(efrm - frm, 2); reason = LE_READ_2(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) printf("%s: station %s disassociated " "by peer (reason %d)\n", ifp->if_xname, ether_sprintf(ni->ni_macaddr), reason); ieee80211_node_leave(ic, ni); } break; default: break; } } void ieee80211_recv_mgmt(struct ieee80211com *ic, struct mbuf *m0, struct ieee80211_node *ni, int subtype, int rssi, u_int32_t rstamp) { switch (subtype) { case IEEE80211_FC0_SUBTYPE_PROBE_RESP: case IEEE80211_FC0_SUBTYPE_BEACON: ieee80211_recv_probe_resp(ic, m0, ni, rssi, rstamp); break; case IEEE80211_FC0_SUBTYPE_PROBE_REQ: ieee80211_recv_probe_req(ic, m0, ni, rssi, rstamp); break; case IEEE80211_FC0_SUBTYPE_AUTH: ieee80211_recv_auth(ic, m0, ni, rssi, rstamp); break; case IEEE80211_FC0_SUBTYPE_ASSOC_REQ: case IEEE80211_FC0_SUBTYPE_REASSOC_REQ: ieee80211_recv_assoc_req(ic, m0, ni, rssi, rstamp); break; case IEEE80211_FC0_SUBTYPE_ASSOC_RESP: case IEEE80211_FC0_SUBTYPE_REASSOC_RESP: ieee80211_recv_assoc_resp(ic, m0, ni, rssi, rstamp); break; case IEEE80211_FC0_SUBTYPE_DEAUTH: ieee80211_recv_deauth(ic, m0, ni, rssi, rstamp); break; case IEEE80211_FC0_SUBTYPE_DISASSOC: ieee80211_recv_disassoc(ic, m0, ni, rssi, rstamp); break; default: IEEE80211_DPRINTF(("%s: mgmt frame with subtype 0x%x not " "handled\n", __func__, subtype)); ic->ic_stats.is_rx_badsubtype++; break; } } #undef IEEE80211_VERIFY_LENGTH #undef IEEE80211_VERIFY_ELEMENT #undef IEEE80211_VERIFY_SSID /* unaligned big endian access */ #define BE_READ_2(p) \ ((u_int16_t)(p)[0] << 8 | (u_int16_t)(p)[1]) #define BE_READ_8(p) \ ((u_int64_t)(p)[0] << 56 | (u_int64_t)(p)[1] << 48 | \ (u_int64_t)(p)[2] << 40 | (u_int64_t)(p)[3] << 32 | \ (u_int64_t)(p)[4] << 24 | (u_int64_t)(p)[5] << 16 | \ (u_int64_t)(p)[6] << 8 | (u_int64_t)(p)[7]) #define BE_WRITE_2(p, v) do { \ (p)[0] = (v) >> 8; \ (p)[1] = (v) & 0xff; \ } while (0) /* unaligned little endian access */ #define LE_READ_8(p) \ ((u_int64_t)(p)[7] << 56 | (u_int64_t)(p)[6] << 48 | \ (u_int64_t)(p)[5] << 40 | (u_int64_t)(p)[4] << 32 | \ (u_int64_t)(p)[3] << 24 | (u_int64_t)(p)[2] << 16 | \ (u_int64_t)(p)[1] << 8 | (u_int64_t)(p)[0]) /* * 4-Way Handshake Message 1 is sent by the authenticator to the supplicant * (see 8.5.3.1). */ void ieee80211_recv_4way_msg1(struct ieee80211com *ic, const struct ieee80211_eapol_key *key, struct ieee80211_node *ni) { u_int8_t snonce[EAPOL_KEY_NONCE_LEN]; const u_int8_t *frm, *efrm; const u_int8_t *pmkid; const u_int8_t *pmk; size_t pmk_len; if (ic->ic_opmode != IEEE80211_M_STA && ic->ic_opmode != IEEE80211_M_IBSS) return; if (BE_READ_8(key->replaycnt) <= ni->ni_replaycnt) return; /* save authenticator's nonce (ANonce) */ memcpy(ni->ni_nonce, key->nonce, EAPOL_KEY_NONCE_LEN); /* parse key data field (shall contain an encapsulated PMKID) */ frm = (const u_int8_t *)&key[1]; efrm = frm + BE_READ_2(key->paylen); pmkid = NULL; while (frm + 2 <= efrm) { if (frm + 2 + frm[1] > efrm) break; switch (frm[0]) { case IEEE80211_ELEMID_VENDOR: if (frm[1] < 4) break; if (memcmp(&frm[2], IEEE80211_OUI, 3) == 0) { switch (frm[5]) { case IEEE80211_KDE_PMKID: pmkid = frm; break; } } break; } frm += 2 + frm[1]; } /* check that we have a valid PMKID KDE */ if (pmkid == NULL || pmkid[1] - 4 < 16) return; /* do not update replaycnt since the frame contains no MIC */ /* generate a new nonce (SNonce) */ get_random_bytes(snonce, EAPOL_KEY_NONCE_LEN); if (ni->ni_akm == IEEE80211_AKM_IEEE8021X) { /* XXX find the PMK in the PMKSA cache using the PMKID */ } else { /* XXX the PMK is the PSK */ } /* derive PTK from PMK */ ieee80211_derive_ptk(pmk, pmk_len, ni->ni_macaddr, ic->ic_myaddr, ni->ni_nonce, snonce, (u_int8_t *)&ni->ni_ptk, sizeof(ni->ni_ptk)); ni->ni_ptk_ok = 1; if (ic->ic_if.if_flags & IFF_DEBUG) printf("%s: received msg %d/%d of the %s handshake from %s\n", ic->ic_if.if_xname, 1, 4, "4-way", ether_sprintf(ni->ni_macaddr)); /* send message 2 to authenticator */ ieee80211_send_4way_msg2(ic, ni); } /* * 4-Way Handshake Message 2 is sent by the supplicant to the authenticator * (see 8.5.3.2). */ void ieee80211_recv_4way_msg2(struct ieee80211com *ic, const struct ieee80211_eapol_key *key, struct ieee80211_node *ni) { const u_int8_t *frm, *efrm; const u_int8_t *rsn; const u_int8_t *pmk; size_t pmk_len; if (ic->ic_opmode != IEEE80211_M_HOSTAP && ic->ic_opmode != IEEE80211_M_IBSS) return; if (BE_READ_8(key->replaycnt) != ni->ni_replaycnt) return; /* derive PTK from PMK */ ieee80211_derive_ptk(pmk, pmk_len, ic->ic_myaddr, ni->ni_macaddr, ni->ni_nonce, key->nonce, (u_int8_t *)&ni->ni_ptk, sizeof(ni->ni_ptk)); ni->ni_ptk_ok = 1; /* parse key data field (shall contain an RSN IE) */ frm = (const u_int8_t *)&key[1]; efrm = frm + BE_READ_2(key->paylen); rsn = NULL; while (frm + 2 <= efrm) { if (frm + 2 + frm[1] > efrm) break; switch (frm[0]) { case IEEE80211_ELEMID_RSN: rsn = frm; break; } frm += 2 + frm[1]; } if (rsn == NULL) return; /* * The RSN IE must match bit-wise with what the STA included in its * (Re)Association Request. */ if (rsn[1] != ni->ni_rsnie[1] || memcmp(rsn, ni->ni_rsnie, 2 + rsn[1]) != 0) return; if (ic->ic_if.if_flags & IFF_DEBUG) printf("%s: received msg %d/%d of the %s handshake from %s\n", ic->ic_if.if_xname, 2, 4, "4-way", ether_sprintf(ni->ni_macaddr)); /* send message 3 to supplicant */ ieee80211_send_4way_msg3(ic, ni); } /* * 4-Way Handshake Message 3 is sent by the authenticator to the supplicant * (see 8.5.3.3). */ void ieee80211_recv_4way_msg3(struct ieee80211com *ic, const struct ieee80211_eapol_key *key, struct ieee80211_node *ni) { struct ieee80211_key k; const u_int8_t *frm, *efrm; const u_int8_t *rsn1, *rsn2, *gtk; if (ic->ic_opmode != IEEE80211_M_STA && ic->ic_opmode != IEEE80211_M_IBSS) return; if (BE_READ_8(key->replaycnt) <= ni->ni_replaycnt) return; /* check that ANonce matches the one received in message 1 */ if (memcmp(key->nonce, ni->ni_nonce, EAPOL_KEY_NONCE_LEN) != 0) return; /* parse key data field */ frm = (const u_int8_t *)&key[1]; efrm = frm + BE_READ_2(key->paylen); rsn1 = rsn2 = gtk = NULL; while (frm + 2 <= efrm) { if (frm + 2 + frm[1] > efrm) break; switch (frm[0]) { case IEEE80211_ELEMID_RSN: if (rsn1 == NULL) rsn1 = frm; else if (rsn2 == NULL) rsn2 = frm; /* ignore if more than two RSN IEs */ break; case IEEE80211_ELEMID_VENDOR: if (frm[1] < 4) break; if (memcmp(&frm[2], IEEE80211_OUI, 3) == 0) { switch (frm[5]) { case IEEE80211_KDE_GTK: gtk = frm; break; } } break; } frm += 2 + frm[1]; } /* first RSN IE is mandatory */ if (rsn1 == NULL) return; /* key data must be encrypted if GTK is included */ if (gtk != NULL && !(BE_READ_2(key->info) & EAPOL_KEY_ENCRYPTED)) return; /* * Check that first RSN IE is identical to the one received in * the beacon or probe response frame. */ if (rsn1[1] != ni->ni_rsnie[1] || memcmp(rsn1, ni->ni_rsnie, 2 + rsn1[1]) != 0) return; /* update the last seen value of the key replay counter field */ ni->ni_replaycnt = BE_READ_8(key->replaycnt); /* * If a second RSN information element is present, use its pairwise * cipher suite or deauthenticate. */ if (rsn2 != NULL) { /* XXX ieee80211_parse_rsn(rsn2); */ } /* install the PTK */ memset(&k, 0, sizeof k); k.k_cipher = ni->ni_pairwise_cipher; k.k_flags = IEEE80211_KEY_TX; k.k_len = ieee80211_cipher_keylen(k.k_cipher); memcpy(k.k_key, ni->ni_ptk.tk, k.k_len); if ((*ic->ic_set_key)(ic, ni, &k) != 0) return; if (gtk != NULL) { /* check that the GTK KDE is valid */ if (gtk[1] - 4 < 2) return; /* install the GTK */ memset(&k, 0, sizeof k); k.k_id = gtk[6] & 3; k.k_cipher = ni->ni_group_cipher; k.k_flags = IEEE80211_KEY_GROUP; if (gtk[6] & (1 << 2)) /* Tx bit */ k.k_flags |= IEEE80211_KEY_TX; k.k_len = gtk[1] - 6; /* check that key length matches group cipher */ if (k.k_len != ieee80211_cipher_keylen(k.k_cipher)) return; /* XXX PTK already installed! */ memcpy(k.k_key, >k[7], k.k_len); k.k_rsc = LE_READ_8(key->rsc); if ((*ic->ic_set_key)(ic, ni, &k) != 0) return; } /* mark the PAE port as valid */ ni->ni_port_valid = 1; if (ic->ic_if.if_flags & IFF_DEBUG) printf("%s: received msg %d/%d of the %s handshake from %s\n", ic->ic_if.if_xname, 3, 4, "4-way", ether_sprintf(ni->ni_macaddr)); /* send message 4 to authenticator */ ieee80211_send_4way_msg4(ic, ni); } /* * 4-Way Handshake Message 4 is sent by the supplicant to the authenticator * (see 8.5.3.4). */ void ieee80211_recv_4way_msg4(struct ieee80211com *ic, const struct ieee80211_eapol_key *key, struct ieee80211_node *ni) { struct ieee80211_key k; if (ic->ic_opmode != IEEE80211_M_HOSTAP && ic->ic_opmode != IEEE80211_M_IBSS) return; if (BE_READ_8(key->replaycnt) != ni->ni_replaycnt) return; /* empty key data field */ /* install the PTK */ memset(&k, 0, sizeof k); k.k_cipher = ni->ni_pairwise_cipher; k.k_flags = IEEE80211_KEY_TX; k.k_len = ieee80211_cipher_keylen(k.k_cipher); memcpy(k.k_key, ni->ni_ptk.tk, k.k_len); if ((*ic->ic_set_key)(ic, ni, &k) != 0) return; if (ic->ic_opmode == IEEE80211_M_IBSS) { if (++ni->ni_key_count == 2) ni->ni_port_valid = 1; } else ni->ni_port_valid = 1; /* increment the 64-bit Key Replay Counter */ ni->ni_replaycnt++; if (ic->ic_if.if_flags & IFF_DEBUG) printf("%s: received msg %d/%d of the %s handshake from %s\n", ic->ic_if.if_xname, 4, 4, "4-way", ether_sprintf(ni->ni_macaddr)); } /* * Group Key Handshake Message 1 is sent by the authenticator to the * supplicant (see 8.5.4.1). */ void ieee80211_recv_group_msg1(struct ieee80211com *ic, const struct ieee80211_eapol_key *key, struct ieee80211_node *ni) { struct ieee80211_key k; const u_int8_t *frm, *efrm; const u_int8_t *gtk; if (ic->ic_opmode != IEEE80211_M_STA && ic->ic_opmode != IEEE80211_M_IBSS) return; if (BE_READ_8(key->replaycnt) <= ni->ni_replaycnt) return; /* parse key data field (shall contain a GTK KDE) */ frm = (const u_int8_t *)&key[1]; efrm = frm + BE_READ_2(key->paylen); gtk = NULL; while (frm + 2 <= efrm) { if (frm + 2 + frm[1] > efrm) break; switch (frm[0]) { case IEEE80211_ELEMID_VENDOR: if (frm[1] < 4) break; if (memcmp(&frm[2], IEEE80211_OUI, 3) == 0) { switch (frm[5]) { case IEEE80211_KDE_GTK: gtk = frm; break; } } break; } frm += 2 + frm[1]; } if (gtk == NULL || !(BE_READ_2(key->info) & EAPOL_KEY_ENCRYPTED)) return; /* check that the GTK KDE is valid */ if (gtk[1] - 4 < 2) return; /* install the GTK */ memset(&k, 0, sizeof k); k.k_id = gtk[6] & 3; k.k_cipher = ni->ni_group_cipher; k.k_flags = IEEE80211_KEY_GROUP; if (gtk[6] & (1 << 2)) /* Tx bit */ k.k_flags |= IEEE80211_KEY_TX; k.k_len = gtk[1] - 6; /* check that key length matches group cipher */ if (k.k_len != ieee80211_cipher_keylen(k.k_cipher)) return; memcpy(k.k_key, >k[7], k.k_len); k.k_rsc = LE_READ_8(key->rsc); if ((*ic->ic_set_key)(ic, ni, &k) != 0) return; /* update the last seen value of the key replay counter field */ ni->ni_replaycnt = BE_READ_8(key->replaycnt); if (ic->ic_if.if_flags & IFF_DEBUG) printf("%s: received msg %d/%d of the %s handshake from %s\n", ic->ic_if.if_xname, 1, 2, "group key", ether_sprintf(ni->ni_macaddr)); /* send message 2 to authenticator */ ieee80211_send_group_msg2(ic, ni); } /* * Group Key Handshake Message 2 is sent by the supplicant to the * authenticator (see 8.5.4.2). */ void ieee80211_recv_group_msg2(struct ieee80211com *ic, const struct ieee80211_eapol_key *key, struct ieee80211_node *ni) { if (ic->ic_opmode != IEEE80211_M_HOSTAP && ic->ic_opmode != IEEE80211_M_IBSS) return; if (BE_READ_8(key->replaycnt) != ni->ni_replaycnt) return; /* empty key data field */ #ifdef notyet if (--ic->ic_keydone_sta == 0) { /* install GTK */ } #endif if (ic->ic_if.if_flags & IFF_DEBUG) printf("%s: received msg %d/%d of the %s handshake from %s\n", ic->ic_if.if_xname, 2, 2, "group key", ether_sprintf(ni->ni_macaddr)); } /* * EAPOL-Key Request frames are sent by the supplicant to request that the * authenticator initiate either a 4-Way Handshake or Group Key Handshake * and to report a MIC failure in a TKIP MSDU. */ void ieee80211_recv_eapol_key_req(struct ieee80211com *ic, const struct ieee80211_eapol_key *key, struct ieee80211_node *ni) { u_int16_t info; if (ic->ic_opmode != IEEE80211_M_HOSTAP && ic->ic_opmode != IEEE80211_M_IBSS) return; info = BE_READ_2(key->info); if (info & EAPOL_KEY_ERROR) { /* TKIP MIC failure */ } else if (info & EAPOL_KEY_PAIRWISE) { /* initiate the 4-Way Handshake */ } else { /* * Should change the GTK, initiate the 4-Way Handshake and * then execute a Group Key Handshake with all supplicants. */ } } #ifdef IEEE80211_DEBUG static void ieee80211_print_eapol_key(struct ieee80211com *ic, const struct ieee80211_eapol_key *key, const struct ieee80211_node *ni) { int i; printf("%s: received EAPOL-Key frame from %s\n", ic->ic_if.if_xname, ether_sprintf((u_int8_t *)ni->ni_macaddr)); printf("version=0x%02x type=0x%02x desc=0x%02x body length=%d " "data length=%d\n", key->version, key->type, key->desc, BE_READ_2(key->len), BE_READ_2(key->paylen)); printf("info=%b\n", BE_READ_2(key->info), "\20\x03PAIRWISE\x06INSTALL\x07KEYACK\x08KEYMIC\x09SECURE" "\x0aERROR\x0bREQUEST\x0cENCRYPTED\x0dSMK"); printf("Key Replay Counter=0x"); for (i = 0; i < 8; i++) printf("%02x", key->replaycnt[i]); printf("\n"); printf("Key Nonce=0x"); for (i = 0; i < EAPOL_KEY_NONCE_LEN; i++) printf("%02x", key->nonce[i]); printf("\n"); printf("EAPOL-Key IV=0x"); for (i = 0; i < EAPOL_KEY_IV_LEN; i++) printf("%02x", key->iv[i]); printf("\n"); printf("Key RSC=0x"); for (i = 0; i < 8; i++) printf("%02x", key->replaycnt[i]); printf("\n"); printf("Key MIC=0x"); for (i = 0; i < EAPOL_KEY_MIC_LEN; i++) printf("%02x", key->mic[i]); printf("\n"); } #endif /* * Process an incoming EAPOL frame. Notice that we are only interested in * EAPOL-Key frames with an IEEE 802.11 descriptor type. */ void ieee80211_recv_eapol(struct ieee80211com *ic, struct mbuf *m0, struct ieee80211_node *ni) { struct ieee80211_eapol_key *key; u_int16_t info; if (m0->m_len < sizeof(*key)) goto out; key = mtod(m0, struct ieee80211_eapol_key *); if (key->version < EAPOL_VERSION) goto out; if (key->type != EAPOL_KEY || (key->desc != EAPOL_KEY_DESC_IEEE80211 && key->desc != EAPOL_KEY_DESC_WPA1)) goto out; /* check packet body length */ if (m0->m_len < 4 + BE_READ_2(key->len)) goto out; /* check key data length */ if (m0->m_len < sizeof(*key) + BE_READ_2(key->paylen)) goto out; #ifdef IEEE80211_DEBUG if (ieee80211_debug > 0) ieee80211_print_eapol_key(ic, key, ni); #endif info = BE_READ_2(key->info); if (info & (EAPOL_KEY_KEYMIC | EAPOL_KEY_ENCRYPTED)) { /* check that we have a valid PTK or TPTK */ if (!ni->ni_ptk_ok) goto out; if (ni->ni_pairwise_cipher == IEEE80211_CIPHER_CCMP && (info & EAPOL_KEY_VERSION_MASK) != EAPOL_KEY_DESC_V2) goto out; /* check Key MIC field using KCK */ if ((info & EAPOL_KEY_KEYMIC) && ieee80211_eapol_key_check_mic(key, ni->ni_ptk.kck) != 0) goto out; /* decrypt Key Data field using KEK */ if ((info & EAPOL_KEY_ENCRYPTED) && ieee80211_eapol_key_decrypt(key, ni->ni_ptk.kek) != 0) goto out; } /* determine message type (see 8.5.3.7) */ if (info & EAPOL_KEY_REQUEST) { /* EAPOL-Key Request */ ieee80211_recv_eapol_key_req(ic, key, ni); } else if (info & EAPOL_KEY_PAIRWISE) { /* 4-Way Handshake */ if (info & EAPOL_KEY_KEYMIC) { if (info & EAPOL_KEY_KEYACK) { if (info & EAPOL_KEY_SECURE) ieee80211_recv_4way_msg4(ic, key, ni); else ieee80211_recv_4way_msg2(ic, key, ni); } else ieee80211_recv_4way_msg3(ic, key, ni); } else ieee80211_recv_4way_msg1(ic, key, ni); } else { /* Group Key Handshake */ if (info & EAPOL_KEY_KEYACK) ieee80211_recv_group_msg1(ic, key, ni); else ieee80211_recv_group_msg2(ic, key, ni); } out: m_freem(m0); } void ieee80211_recv_pspoll(struct ieee80211com *ic, struct mbuf *m0, int rssi, u_int32_t rstamp) { struct ifnet *ifp = &ic->ic_if; struct ieee80211_frame *wh; struct ieee80211_node *ni; struct mbuf *m; u_int16_t aid; if (ic->ic_set_tim == NULL) /* no powersaving functionality */ return; wh = mtod(m0, struct ieee80211_frame *); if ((ni = ieee80211_find_node(ic, wh->i_addr2)) == NULL) { if (ifp->if_flags & IFF_DEBUG) printf("%s: station %s sent bogus power save poll\n", ifp->if_xname, ether_sprintf(wh->i_addr2)); return; } memcpy(&aid, wh->i_dur, sizeof(wh->i_dur)); if ((aid & 0xc000) != 0xc000) { if (ifp->if_flags & IFF_DEBUG) printf("%s: station %s sent bogus aid %x\n", ifp->if_xname, ether_sprintf(wh->i_addr2), aid); return; } if (aid != ni->ni_associd) { if (ifp->if_flags & IFF_DEBUG) printf("%s: station %s aid %x doesn't match pspoll " "aid %x\n", ifp->if_xname, ether_sprintf(wh->i_addr2), ni->ni_associd, aid); return; } /* Okay, take the first queued packet and put it out... */ IF_DEQUEUE(&ni->ni_savedq, m); if (m == NULL) { if (ifp->if_flags & IFF_DEBUG) printf("%s: station %s sent pspoll, " "but no packets are saved\n", ifp->if_xname, ether_sprintf(wh->i_addr2)); return; } wh = mtod(m, struct ieee80211_frame *); /* * If this is the last packet, turn off the TIM fields. * If there are more packets, set the more packets bit. */ if (IF_IS_EMPTY(&ni->ni_savedq)) (*ic->ic_set_tim)(ic, ni->ni_associd, 0); else wh->i_fc[1] |= IEEE80211_FC1_MORE_DATA; if (ifp->if_flags & IFF_DEBUG) printf("%s: enqueued power saving packet for station %s\n", ifp->if_xname, ether_sprintf(ni->ni_macaddr)); IF_ENQUEUE(&ic->ic_pwrsaveq, m); (*ifp->if_start)(ifp); } int ieee80211_do_slow_print(struct ieee80211com *ic, int *did_print) { static const struct timeval merge_print_intvl = { .tv_sec = 1, .tv_usec = 0 }; if ((ic->ic_if.if_flags & IFF_LINK0) == 0) return 0; if (!*did_print && (ic->ic_if.if_flags & IFF_DEBUG) == 0 && !ratecheck(&ic->ic_last_merge_print, &merge_print_intvl)) return 0; *did_print = 1; return 1; } /* ieee80211_ibss_merge helps merge 802.11 ad hoc networks. The * convention, set by the Wireless Ethernet Compatibility Alliance * (WECA), is that an 802.11 station will change its BSSID to match * the "oldest" 802.11 ad hoc network, on the same channel, that * has the station's desired SSID. The "oldest" 802.11 network * sends beacons with the greatest TSF timestamp. * * Return ENETRESET if the BSSID changed, 0 otherwise. * * XXX Perhaps we should compensate for the time that elapses * between the MAC receiving the beacon and the host processing it * in ieee80211_ibss_merge. */ int ieee80211_ibss_merge(struct ieee80211com *ic, struct ieee80211_node *ni, u_int64_t local_tsft) { u_int64_t beacon_tsft; int did_print = 0, sign; union { u_int64_t word; u_int8_t tstamp[8]; } u; /* ensure alignment */ (void)memcpy(&u, &ni->ni_tstamp[0], sizeof(u)); beacon_tsft = letoh64(u.word); /* we are faster, let the other guy catch up */ if (beacon_tsft < local_tsft) sign = -1; else sign = 1; if (IEEE80211_ADDR_EQ(ni->ni_bssid, ic->ic_bss->ni_bssid)) { if (!ieee80211_do_slow_print(ic, &did_print)) return 0; printf("%s: tsft offset %s%llu\n", ic->ic_if.if_xname, (sign < 0) ? "-" : "", (sign < 0) ? (local_tsft - beacon_tsft) : (beacon_tsft - local_tsft)); return 0; } if (sign < 0) return 0; if (ieee80211_match_bss(ic, ni) != 0) return 0; if (ieee80211_do_slow_print(ic, &did_print)) { printf("%s: ieee80211_ibss_merge: bssid mismatch %s\n", ic->ic_if.if_xname, ether_sprintf(ni->ni_bssid)); printf("%s: my tsft %llu beacon tsft %llu\n", ic->ic_if.if_xname, local_tsft, beacon_tsft); printf("%s: sync TSF with %s\n", ic->ic_if.if_xname, ether_sprintf(ni->ni_macaddr)); } ic->ic_flags &= ~IEEE80211_F_SIBSS; /* negotiate rates with new IBSS */ ieee80211_fix_rate(ic, ni, IEEE80211_F_DOFRATE | IEEE80211_F_DONEGO | IEEE80211_F_DODEL); if (ni->ni_rates.rs_nrates == 0) { if (ieee80211_do_slow_print(ic, &did_print)) { printf("%s: rates mismatch, BSSID %s\n", ic->ic_if.if_xname, ether_sprintf(ni->ni_bssid)); } return 0; } if (ieee80211_do_slow_print(ic, &did_print)) { printf("%s: sync BSSID %s -> ", ic->ic_if.if_xname, ether_sprintf(ic->ic_bss->ni_bssid)); printf("%s ", ether_sprintf(ni->ni_bssid)); printf("(from %s)\n", ether_sprintf(ni->ni_macaddr)); } ieee80211_node_newstate(ni, IEEE80211_STA_BSS); (*ic->ic_node_copy)(ic, ic->ic_bss, ni); return ENETRESET; }