ieee80211_input.c.svn-base

最新之atheros芯片driver source code, 基于linux操作系统,內含atheros芯片HAL全部代码

	ieee80211_dev_kfree_skb(&skb);
	return type; 
} 
EXPORT_SYMBOL(ieee80211_input_all); 

/*
 * Determines whether a frame should be accepted, based on information
 * about the frame's origin and encryption, and policy for this vap.
 */
static int accept_data_frame(struct ieee80211vap *vap,
	struct ieee80211_node *ni, struct ieee80211_key *key,
	struct sk_buff *skb, struct ether_header *eh)
{
#define IS_EAPOL(eh) ((eh)->ether_type == __constant_htons(ETHERTYPE_PAE))
#define PAIRWISE_SET(vap) ((vap)->iv_nw_keys[0].wk_cipher != &ieee80211_cipher_none)
	if (IS_EAPOL(eh)) {
		/* encrypted eapol is always OK */
		if (key)
			return 1;
		/* cleartext eapol is OK if we don't have pairwise keys yet */
		if (!PAIRWISE_SET(vap))
			return 1;
		/* cleartext eapol is OK if configured to allow it */
		if (!IEEE80211_VAP_DROPUNENC_EAPOL(vap))
			return 1;
		/* cleartext eapol is OK if other unencrypted is OK */
		if (!(vap->iv_flags & IEEE80211_F_DROPUNENC))
			return 1;
		/* not OK */
		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
				      eh->ether_shost, "data",
				      "unauthorized port: ether type 0x%x len %u",
				      ntohs(eh->ether_type), skb->len);
		vap->iv_stats.is_rx_unauth++;
		vap->iv_devstats.rx_errors++;
		IEEE80211_NODE_STAT(ni, rx_unauth);
		return 0;
	}

	if (!ieee80211_node_is_authorized(ni)) {
		/*
		* Deny any non-PAE frames received prior to
		* authorization.  For open/shared-key
		* authentication the port is mark authorized
		* after authentication completes.  For 802.1x
		* the port is not marked authorized by the
		* authenticator until the handshake has completed.
		*/
		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
				      eh->ether_shost, "data",
				      "unauthorized port: ether type 0x%x len %u",
				      ntohs(eh->ether_type), skb->len);
		vap->iv_stats.is_rx_unauth++;
		vap->iv_devstats.rx_errors++;
		IEEE80211_NODE_STAT(ni, rx_unauth);
		return 0;
	} else {
		/*
		* When denying unencrypted frames, discard
		* any non-PAE frames received without encryption.
		*/
		if ((vap->iv_flags & IEEE80211_F_DROPUNENC) && key == NULL) {
			IEEE80211_NODE_STAT(ni, rx_unencrypted);
			return 0;
		}
	}
	return 1;

#undef IS_EAPOL
#undef PAIRWISE_SET
}

/*
 * This function reassemble fragments using the skb of the 1st fragment,
 * if large enough. If not, a new skb is allocated to hold incoming
 * fragments.
 *
 * Fragments are copied at the end of the previous fragment.  A different
 * strategy could have been used, where a non-linear skb is allocated and
 * fragments attached to that skb.
 */
static struct sk_buff *
ieee80211_defrag(struct ieee80211_node *ni, struct sk_buff *skb, int hdrlen)
{
	struct ieee80211_frame *wh = (struct ieee80211_frame *)skb->data;
	u_int16_t rxseq, last_rxseq;
	u_int8_t fragno, last_fragno;
	u_int8_t more_frag = wh->i_fc[1] & IEEE80211_FC1_MORE_FRAG;

	rxseq = le16_to_cpu(*(__le16 *)wh->i_seq) >> IEEE80211_SEQ_SEQ_SHIFT;
	fragno = le16_to_cpu(*(__le16 *)wh->i_seq) & IEEE80211_SEQ_FRAG_MASK;

	/* Quick way out, if there's nothing to defragment */
	if (!more_frag && fragno == 0 && ni->ni_rxfrag == NULL)
		return skb;

	/*
	 * Remove frag to ensure it doesn't get reaped by timer.
	 */
	if (ni->ni_table == NULL) {
		/*
		 * Should never happen.  If the node is orphaned (not in
		 * the table) then input packets should not reach here.
		 * Otherwise, a concurrent request that yanks the table
		 * should be blocked by other interlocking and/or by first
		 * shutting the driver down.  Regardless, be defensive
		 * here and just bail
		 */
		/* XXX need msg+stat */
		ieee80211_dev_kfree_skb(&skb);
		return NULL;
	}

	/*
	 * Update the time stamp.  As a side effect, it
	 * also makes sure that the timer will not change
	 * ni->ni_rxfrag for at least 1 second, or in
	 * other words, for the remaining of this function.
	 * XXX HUGE HORRIFIC HACK
	 */
	ni->ni_rxfragstamp = jiffies;

	/*
	 * Validate that fragment is in order and
	 * related to the previous ones.
	 */
	if (ni->ni_rxfrag) {
		struct ieee80211_frame *lwh;

		lwh = (struct ieee80211_frame *)ni->ni_rxfrag->data;
		last_rxseq = le16_to_cpu(*(__le16 *)lwh->i_seq) >>
			IEEE80211_SEQ_SEQ_SHIFT;
		last_fragno = le16_to_cpu(*(__le16 *)lwh->i_seq) &
			IEEE80211_SEQ_FRAG_MASK;
		if (rxseq != last_rxseq
		    || fragno != last_fragno + 1
		    || (!IEEE80211_ADDR_EQ(wh->i_addr1, lwh->i_addr1))
		    || (!IEEE80211_ADDR_EQ(wh->i_addr2, lwh->i_addr2))
		    || (ni->ni_rxfrag->end - ni->ni_rxfrag->tail <
			skb->len)) {
			/*
			 * Unrelated fragment or no space for it,
			 * clear current fragments
			 */
			ieee80211_dev_kfree_skb(&ni->ni_rxfrag);
		}
	}

	/* If this is the first fragment */
 	if (ni->ni_rxfrag == NULL && fragno == 0) {
		ni->ni_rxfrag = skb;
		/* If more frags are coming */
		if (more_frag) {
			if (skb_is_nonlinear(skb)) {
				/*
				 * We need a continous buffer to
				 * assemble fragments
				 */
				ni->ni_rxfrag = skb_copy(skb, GFP_ATOMIC);
				if (ni->ni_rxfrag) {
					ieee80211_skb_copy_noderef(skb, ni->ni_rxfrag);
					ieee80211_dev_kfree_skb(&skb);
				}
			}
			/*
			 * Check that we have enough space to hold
			 * incoming fragments
			 * XXX 4-address/QoS frames?
			 */
			else if ((skb_end_pointer(skb) - skb->head) <
				 (ni->ni_vap->iv_dev->mtu + hdrlen)) {
				ni->ni_rxfrag = skb_copy_expand(skb, 0,
					(ni->ni_vap->iv_dev->mtu + hdrlen) -
					(skb_end_pointer(skb) - skb->head),
					GFP_ATOMIC);
				if (ni->ni_rxfrag)
					ieee80211_skb_copy_noderef(skb, ni->ni_rxfrag);
				ieee80211_dev_kfree_skb(&skb);
			}
		}
	} else {
		if (ni->ni_rxfrag) {
			struct ieee80211_frame *lwh = (struct ieee80211_frame *)
				ni->ni_rxfrag->data;

			/*
			 * We know we have enough space to copy,
			 * we've verified that before
			 */
			/* Copy current fragment at end of previous one */
			memcpy(skb_tail_pointer(ni->ni_rxfrag),
			       skb->data + hdrlen, skb->len - hdrlen);
			/* Update tail and length */
			skb_put(ni->ni_rxfrag, skb->len - hdrlen);
			/* Keep a copy of last sequence and fragno */
			*(__le16 *)lwh->i_seq = *(__le16 *)wh->i_seq;
		}
		/* we're done with the fragment */
		ieee80211_dev_kfree_skb(&skb);
	}

	if (more_frag) {
		/* More to come */
		skb = NULL;
	} else {
		/* Last fragment received, we're done! */
		skb = ni->ni_rxfrag;
		ni->ni_rxfrag = NULL;
	}
	return skb;
}

static void
ieee80211_deliver_data(struct ieee80211_node *ni, struct sk_buff *skb)
{
	struct ieee80211vap *vap = ni->ni_vap;
	struct net_device *dev = vap->iv_dev;
	struct ether_header *eh = (struct ether_header *)skb->data;
	struct ieee80211_node *tni;
	int ret;

#ifdef ATH_SUPERG_XR
	/*
	 * if it is a XR vap, send the data to associated normal net
	 * device. XR vap has a net device which is not registered with
	 * OS. 
	 */
	if (vap->iv_xrvap && vap->iv_flags & IEEE80211_F_XR)
		dev = vap->iv_xrvap->iv_dev;
#endif

	/* perform as a bridge within the vap */
	/* XXX intra-vap bridging only */
	if (vap->iv_opmode == IEEE80211_M_HOSTAP &&
	    (vap->iv_flags & IEEE80211_F_NOBRIDGE) == 0) {
		struct sk_buff *skb1 = NULL;

		if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
			/* Create a SKB for the BSS to send out. */
			skb1 = skb_copy(skb, GFP_ATOMIC);
			if (skb1)
				SKB_NI(skb1) = ieee80211_ref_node(vap->iv_bss); 
		}
		else {
			/* Check if destination is associated with the
			 * same VAP and authorized to receive traffic.
			 * Beware of traffic destined for the VAP itself;
			 * sending it will not work; just let it be
			 * delivered normally. */
			struct ieee80211_node *ni1 = ieee80211_find_node(
				&vap->iv_ic->ic_sta, eh->ether_dhost);
			if (ni1 != NULL) {
				if ((ni1->ni_vap == vap) &&
				    (ni1 != vap->iv_bss) &&
				    ieee80211_node_is_authorized(ni1)) {
					skb1 = skb;
					skb = NULL;
				}
				/* XXX: statistic? */
				ieee80211_unref_node(&ni1);
			}
		}
		if (skb1 != NULL) {
			skb1->dev = dev;
			skb_reset_mac_header(skb1);
			skb_set_network_header(skb1, sizeof(struct ether_header));

			skb1->protocol = __constant_htons(ETH_P_802_2);

			/* This SKB is being emitted to the physical/parent
			 * device, which maintains node references. However,
			 * there is kernel code in between which does not.
			 * Therefore, the ref. is cleaned if the SKB is
			 * dropped. */
			tni = SKB_NI(skb1);
			/* XXX: Insert vlan tag before queuing it? */
			if (dev_queue_xmit(skb1) == NET_XMIT_DROP) {
				vap->iv_devstats.tx_dropped++;
				if (tni != NULL)
					ieee80211_unref_node(&tni);
			}
			/* SKB is no longer ours, either way after dev_queue_xmit. */
			skb1 = NULL; 
		}
	}

	if (skb != NULL) {
		vap->iv_devstats.rx_packets++;
		vap->iv_devstats.rx_bytes += skb->len;
		dev->last_rx = jiffies;

		skb->dev = dev;
#ifdef USE_HEADERLEN_RESV
		skb->protocol = ath_eth_type_trans(skb, dev);
#else
		skb->protocol = eth_type_trans(skb, dev);
#endif
		tni = SKB_NI(skb);
		if ((ni->ni_vlan != 0) && (vap->iv_vlgrp != NULL))
			/* Attach VLAN tag. */
			ret = vlan_hwaccel_rx(skb,
					vap->iv_vlgrp, ni->ni_vlan);
		else
			ret = netif_rx(skb);
		if (ret == NET_RX_DROP)
			vap->iv_devstats.rx_dropped++;
		if (tni != NULL)
			ieee80211_unref_node(&tni);
		skb = NULL; /* SKB is no longer ours */
	}
}

/* This function removes the 802.11 header, including LLC/SNAP headers and 
 * replaces it with an Ethernet II header. */
static struct sk_buff *
ieee80211_decap(struct ieee80211vap *vap, struct sk_buff *skb, int hdrlen)
{
	const struct llc snap_hdr = {.llc_dsap = LLC_SNAP_LSAP,
				     .llc_ssap = LLC_SNAP_LSAP,
				     .llc_snap.control = LLC_UI,
				     .llc_snap.org_code = {0x0, 0x0, 0x0}};
	struct ieee80211_qosframe_addr4 wh;	/* Max size address frames */
	struct ether_header *eh;
	struct llc *llc;
	__be16 ether_type = 0;

	memcpy(&wh, skb->data, hdrlen);	/* Make a copy of the variably sized .11 header */

	llc = (struct llc *)skb_pull(skb, hdrlen);
	/* XXX: For some unknown reason some APs think they are from DEC and 
	 * use an OUI of 00-00-f8. This should be killed as soon as sanity is 
	 * restored. */
	if ((skb->len >= LLC_SNAPFRAMELEN) && (memcmp(&snap_hdr, llc, 5) == 0) &&
			((llc->llc_snap.org_code[2] == 0x0) || 
			 (llc->llc_snap.org_code[2] == 0xf8))) {
		ether_type = llc->llc_un.type_snap.ether_type;
		skb_pull(skb, LLC_SNAPFRAMELEN);
		llc = NULL;
	}

	eh = (struct ether_header *)skb_push(skb, sizeof(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:
		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr4);
		break;
	}

	if (llc != NULL)
		eh->ether_type = htons(skb->len - sizeof(*eh));
	else
		eh->ether_type = ether_type;

	return skb;
}

/*
 * Install received rate set information in the node's state block.
 */
int
ieee80211_setup_rates(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) {
			struct ieee80211vap *vap = ni->ni_vap;

			nxrates = IEEE80211_RATE_MAXSIZE - rs->rs_nrates;
			IEEE80211_NOTE(vap, IEEE80211_MSG_XRATE, ni,
				"extended rate set too large;"
				" only using %u of %u rates",
				nxrates, xrates[1]);
			vap->iv_stats.is_rx_rstoobig++;
		}
		memcpy(rs->rs_rates + rs->rs_nrates, xrates+2, nxrates);
		rs->rs_nrates += nxrates;
	}
	return ieee80211_fix_rate(ni, flags);
}

static void
ieee80211_auth_open(struct ieee80211_node *ni, struct ieee80211_frame *wh,
	int rssi, u_int64_t rtsf, u_int16_t seq, u_int16_t status)
{
	struct ieee80211vap *vap = ni->ni_vap;
	unsigned int tmpnode = 0;

	if (ni->ni_authmode == IEEE80211_AUTH_SHARED) {
		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_AUTH,
			ni->ni_macaddr, "open auth",
			"bad sta auth mode %u", ni->ni_authmode);
		vap->iv_stats.is_rx_bad_auth++;	/* XXX maybe a unique error? */
		if (vap->iv_opmode == IEEE80211_M_HOSTAP) {
			if (ni == vap->iv_bss) {
				ni = ieee80211_dup_bss(vap, wh->i_addr2, 0);
				if (ni == NULL)
					return;
				tmpnode = 1;
			}
			IEEE80211_SEND_MGMT(ni,	IEEE80211_FC0_SUBTYPE_AUTH,
				(seq + 1) | (IEEE80211_STATUS_ALG << 16));

			if (tmpnode)
				ieee80211_unref_node(&ni);
			return;
		}
	}
	switch (vap->iv_opmode) {
	case IEEE80211_M_IBSS:
		if (vap->iv_state != IEEE80211_S_RUN ||
		    seq != IEEE80211_AUTH_OPEN_REQUEST) {
			vap->iv_stats.is_rx_bad_auth++;
			return;
		}
		ieee80211_new_state(vap, IEEE80211_S_AUTH,
			wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK);
		break;

	case IEEE80211_M_AHDEMO:
	case IEEE80211_M_WDS: