p80211conv.c

对于无线网卡采用prism芯片的linux的开源驱动.

/* src/p80211/p80211conv.c
*
* Ether/802.11 conversions and packet buffer routines
*
* Copyright (C) 1999 AbsoluteValue Systems, Inc.  All Rights Reserved.
* --------------------------------------------------------------------
*
* linux-wlan
*
*   The contents of this file are subject to the Mozilla Public
*   License Version 1.1 (the "License"); you may not use this file
*   except in compliance with the License. You may obtain a copy of
*   the License at http://www.mozilla.org/MPL/
*
*   Software distributed under the License is distributed on an "AS
*   IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
*   implied. See the License for the specific language governing
*   rights and limitations under the License.
*
*   Alternatively, the contents of this file may be used under the
*   terms of the GNU Public License version 2 (the "GPL"), in which
*   case the provisions of the GPL are applicable instead of the
*   above.  If you wish to allow the use of your version of this file
*   only under the terms of the GPL and not to allow others to use
*   your version of this file under the MPL, indicate your decision
*   by deleting the provisions above and replace them with the notice
*   and other provisions required by the GPL.  If you do not delete
*   the provisions above, a recipient may use your version of this
*   file under either the MPL or the GPL.
*
* --------------------------------------------------------------------
*
* Inquiries regarding the linux-wlan Open Source project can be
* made directly to:
*
* AbsoluteValue Systems Inc.
* [e-mail]
* http://www.linux-wlan.com
*
* --------------------------------------------------------------------
*
* Portions of the development of this software were funded by 
* Intersil Corporation as part of PRISM(R) chipset product development.
*
* --------------------------------------------------------------------
*
* This file defines the functions that perform Ethernet to/from
* 802.11 frame conversions. 
*
* --------------------------------------------------------------------
*/
/*================================================================*/
/* System Includes */

#define __NO_VERSION__		/* prevent the static definition */

#include <linux/config.h>
#include <linux/version.h>

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/types.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/wireless.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/if_ether.h>

#include <asm/byteorder.h>

#include <wlan/version.h>
#include <wlan/wlan_compat.h>

/*================================================================*/
/* Project Includes */

#include <wlan/p80211types.h>
#include <wlan/p80211hdr.h>
#include <wlan/p80211conv.h>
#include <wlan/p80211mgmt.h>
#include <wlan/p80211msg.h>
#include <wlan/p80211netdev.h>
#include <wlan/p80211ioctl.h>
#include <wlan/p80211req.h>


/*================================================================*/
/* Local Constants */

/*================================================================*/
/* Local Macros */


/*================================================================*/
/* Local Types */


/*================================================================*/
/* Local Static Definitions */

static UINT8	oui_rfc1042[] = {0x00, 0x00, 0x00};
static UINT8	oui_8021h[] = {0x00, 0x00, 0xf8};

/*================================================================*/
/* Local Function Declarations */


/*================================================================*/
/* Function Definitions */

/*----------------------------------------------------------------
* p80211pb_ether_to_80211
*
* Uses the contents of the ether frame and the etherconv setting
* to build the elements of the 802.11 frame.  
*
* We don't actually set 
* up the frame header here.  That's the MAC's job.  We're only handling
* conversion of DIXII or 802.3+LLC frames to something that works
* with 802.11.
*
* Note -- 802.11 header is NOT part of the skb.  Likewise, the 802.11
*         FCS is also not present and will need to be added elsewhere.
*
* Arguments:
*	ethconv		Conversion type to perform
*	skb		skbuff containing the ether frame
*       p80211_hdr      802.11 header
*
* Returns: 
*	0 on success, non-zero otherwise
*	
* Call context:
*	May be called in interrupt or non-interrupt context
----------------------------------------------------------------*/
int skb_ether_to_p80211( wlandevice_t *wlandev, UINT32 ethconv, struct sk_buff *skb, p80211_hdr_t *p80211_hdr, p80211_metawep_t *p80211_wep)
{

	UINT16          fc;
	UINT16          proto;
	wlan_ethhdr_t   e_hdr; 
	wlan_llc_t      *e_llc;
	wlan_snap_t     *e_snap;
	int foo;

	DBFENTER;
	memcpy(&e_hdr, skb->data, sizeof(e_hdr)); 

	if (skb->len <= 0) {
		WLAN_LOG_DEBUG(1, "zero-length skb!\n");
		return 1;
	}

	if ( ethconv == WLAN_ETHCONV_ENCAP ) { /* simplest case */
	        WLAN_LOG_DEBUG(3, "ENCAP len: %d\n", skb->len);
		/* here, we don't care what kind of ether frm. Just stick it */
		/*  in the 80211 payload */
		/* which is to say, leave the skb alone. */
	} else {
		/* step 1: classify ether frame, DIX or 802.3? */
		proto = ntohs(e_hdr.type);
		if ( proto <= 1500 ) { 
		        WLAN_LOG_DEBUG(3, "802.3 len: %d\n", skb->len);
                        /* codes <= 1500 reserved for 802.3 lengths */
			/* it's 802.3, pass ether payload unchanged,  */

			/* trim off ethernet header */
			skb_pull(skb, WLAN_ETHHDR_LEN);

			/*   leave off any PAD octets.  */
			skb_trim(skb, proto);
		} else {
		        WLAN_LOG_DEBUG(3, "DIXII len: %d\n", skb->len);
			/* it's DIXII, time for some conversion */

			/* trim off ethernet header */
			skb_pull(skb, WLAN_ETHHDR_LEN);

			/* tack on SNAP */
			e_snap = (wlan_snap_t *) skb_push(skb, sizeof(wlan_snap_t));
			e_snap->type = htons(proto);
			if ( ethconv == WLAN_ETHCONV_8021h && p80211_stt_findproto(proto) ) {
				memcpy( e_snap->oui, oui_8021h, WLAN_IEEE_OUI_LEN);
			} else {
				memcpy( e_snap->oui, oui_rfc1042, WLAN_IEEE_OUI_LEN);
			}

			/* tack on llc */
			e_llc = (wlan_llc_t *) skb_push(skb, sizeof(wlan_llc_t));
			e_llc->dsap = 0xAA;	/* SNAP, see IEEE 802 */
			e_llc->ssap = 0xAA;
			e_llc->ctl = 0x03;
			
		}
	}

	/* Set up the 802.11 header */
	/* It's a data frame */
	fc = host2ieee16( WLAN_SET_FC_FTYPE(WLAN_FTYPE_DATA) |  
			  WLAN_SET_FC_FSTYPE(WLAN_FSTYPE_DATAONLY));

	switch ( wlandev->macmode ) {
	case WLAN_MACMODE_IBSS_STA:
		memcpy(p80211_hdr->a3.a1, &e_hdr.daddr, WLAN_ADDR_LEN);
		memcpy(p80211_hdr->a3.a2, wlandev->netdev->dev_addr, WLAN_ADDR_LEN);
		memcpy(p80211_hdr->a3.a3, wlandev->bssid, WLAN_ADDR_LEN);
		break;
	case WLAN_MACMODE_ESS_STA:
		fc |= host2ieee16(WLAN_SET_FC_TODS(1));
		memcpy(p80211_hdr->a3.a1, wlandev->bssid, WLAN_ADDR_LEN);
		memcpy(p80211_hdr->a3.a2, wlandev->netdev->dev_addr, WLAN_ADDR_LEN);
		memcpy(p80211_hdr->a3.a3, &e_hdr.daddr, WLAN_ADDR_LEN);
		break;
	case WLAN_MACMODE_ESS_AP:
		fc |= host2ieee16(WLAN_SET_FC_FROMDS(1));
		memcpy(p80211_hdr->a3.a1, &e_hdr.daddr, WLAN_ADDR_LEN);
		memcpy(p80211_hdr->a3.a2, wlandev->bssid, WLAN_ADDR_LEN);
		memcpy(p80211_hdr->a3.a3, &e_hdr.saddr, WLAN_ADDR_LEN);
		break;
	default:
		WLAN_LOG_ERROR("Error: Converting eth to wlan in unknown mode.\n");
		return 1;
		break;
	}

	p80211_wep->data = NULL;

	if ((wlandev->hostwep & HOSTWEP_PRIVACYINVOKED) && (wlandev->hostwep & HOSTWEP_ENCRYPT)) {
		// XXXX need to pick keynum other than default?

#if 1
		p80211_wep->data = kmalloc(skb->len, GFP_ATOMIC);
#else
		p80211_wep->data = skb->data;
#endif

		if ((foo = wep_encrypt(wlandev, skb->data, p80211_wep->data, 
				       skb->len, 
				(wlandev->hostwep & HOSTWEP_DEFAULTKEY_MASK),
				p80211_wep->iv, p80211_wep->icv))) {
			WLAN_LOG_WARNING("Host en-WEP failed, dropping frame (%d).\n", foo);
			return 2;
		}
		fc |= host2ieee16(WLAN_SET_FC_ISWEP(1));
	}
	

	//	skb->nh.raw = skb->data;

	p80211_hdr->a3.fc = fc;
	p80211_hdr->a3.dur = 0;
	p80211_hdr->a3.seq = 0;

	DBFEXIT;
	return 0;
}

/* jkriegl: from orinoco, modified */
void orinoco_spy_gather(wlandevice_t *wlandev, char *mac, p80211_rxmeta_t *rxmeta)
{
        int i;

        /* Gather wireless spy statistics: for each packet, compare the
         * source address with out list, and if match, get the stats... */

        for (i = 0; i < wlandev->spy_number; i++) {

                if (!memcmp(wlandev->spy_address[i], mac, ETH_ALEN)) {
			memcpy(wlandev->spy_address[i], mac, ETH_ALEN);
                        wlandev->spy_stat[i].level = rxmeta->signal;
                        wlandev->spy_stat[i].noise = rxmeta->noise;
                        wlandev->spy_stat[i].qual = (rxmeta->signal > rxmeta->noise) ? \
                                                     (rxmeta->signal - rxmeta->noise) : 0;
                        wlandev->spy_stat[i].updated = 0x7;
                }
        }
}

/*----------------------------------------------------------------
* p80211pb_80211_to_ether
*
* Uses the contents of a received 802.11 frame and the etherconv 
* setting to build an ether frame.
*
* This function extracts the src and dest address from the 802.11
* frame to use in the construction of the eth frame.
*
* Arguments:
*	ethconv		Conversion type to perform
*	skb		Packet buffer containing the 802.11 frame
*
* Returns: 
*	0 on success, non-zero otherwise
*	
* Call context:
*	May be called in interrupt or non-interrupt context
----------------------------------------------------------------*/
int skb_p80211_to_ether( wlandevice_t *wlandev, UINT32 ethconv, struct sk_buff *skb)
{
	netdevice_t     *netdev = wlandev->netdev;
	UINT16          fc;
	UINT            payload_length;
	UINT            payload_offset;
	UINT8		daddr[WLAN_ETHADDR_LEN];
	UINT8		saddr[WLAN_ETHADDR_LEN];
	p80211_hdr_t    *w_hdr;
	wlan_ethhdr_t   *e_hdr;
	wlan_llc_t      *e_llc;
	wlan_snap_t     *e_snap;

	int foo;

	DBFENTER;
	
	payload_length = skb->len - WLAN_HDR_A3_LEN - WLAN_CRC_LEN;
	payload_offset = WLAN_HDR_A3_LEN;

	w_hdr = (p80211_hdr_t *) skb->data;

        /* setup some vars for convenience */
	fc = ieee2host16(w_hdr->a3.fc);
	if ( (WLAN_GET_FC_TODS(fc) == 0) && (WLAN_GET_FC_FROMDS(fc) == 0) ) {
		memcpy(daddr, w_hdr->a3.a1, WLAN_ETHADDR_LEN);
		memcpy(saddr, w_hdr->a3.a2, WLAN_ETHADDR_LEN);
	} else if( (WLAN_GET_FC_TODS(fc) == 0) && (WLAN_GET_FC_FROMDS(fc) == 1) ) {
		memcpy(daddr, w_hdr->a3.a1, WLAN_ETHADDR_LEN);
		memcpy(saddr, w_hdr->a3.a3, WLAN_ETHADDR_LEN);
	} else if( (WLAN_GET_FC_TODS(fc) == 1) && (WLAN_GET_FC_FROMDS(fc) == 0) ) {
		memcpy(daddr, w_hdr->a3.a3, WLAN_ETHADDR_LEN);
		memcpy(saddr, w_hdr->a3.a2, WLAN_ETHADDR_LEN);
	} else {
		payload_offset = WLAN_HDR_A4_LEN;
		payload_length -= ( WLAN_HDR_A4_LEN - WLAN_HDR_A3_LEN );
		if (payload_length < 0 ) {
			WLAN_LOG_ERROR("A4 frame too short!\n");
			return 1;
		}
		memcpy(daddr, w_hdr->a4.a3, WLAN_ETHADDR_LEN);
		memcpy(saddr, w_hdr->a4.a4, WLAN_ETHADDR_LEN);
	}