llc_output.c 2.97 KB
Newer Older
Linus Torvalds's avatar
Linus Torvalds committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
/*
 * llc_output.c - LLC minimal output path
 *
 * Copyright (c) 1997 by Procom Technology, Inc.
 * 		 2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
 *
 * This program can be redistributed or modified under the terms of the
 * GNU General Public License version 2 as published by the Free Software
 * Foundation.
 * This program is distributed without any warranty or implied warranty
 * of merchantability or fitness for a particular purpose.
 *
 * See the GNU General Public License version 2 for more details.
 */

#include <linux/if_arp.h>
#include <linux/if_tr.h>
#include <linux/netdevice.h>
#include <linux/trdevice.h>
#include <linux/skbuff.h>
#include <net/llc.h>
#include <net/llc_pdu.h>

/**
 *	llc_mac_hdr_init - fills MAC header fields
 *	@skb: Address of the frame to initialize its MAC header
 *	@sa: The MAC source address
 *	@da: The MAC destination address
 *
 *	Fills MAC header fields, depending on MAC type. Returns 0, If MAC type
 *	is a valid type and initialization completes correctly 1, otherwise.
 */
33 34
int llc_mac_hdr_init(struct sk_buff *skb,
		     const unsigned char *sa, const unsigned char *da)
Linus Torvalds's avatar
Linus Torvalds committed
35 36 37 38 39 40 41 42
{
	int rc = 0;

	switch (skb->dev->type) {
#ifdef CONFIG_TR
	case ARPHRD_IEEE802_TR: {
		struct net_device *dev = skb->dev;
		struct trh_hdr *trh;
43

44 45
		skb_push(skb, sizeof(*trh));
		skb_reset_mac_header(skb);
Linus Torvalds's avatar
Linus Torvalds committed
46 47 48 49 50 51 52 53 54 55
		trh = tr_hdr(skb);
		trh->ac = AC;
		trh->fc = LLC_FRAME;
		if (sa)
			memcpy(trh->saddr, sa, dev->addr_len);
		else
			memset(trh->saddr, 0, dev->addr_len);
		if (da) {
			memcpy(trh->daddr, da, dev->addr_len);
			tr_source_route(skb, trh, dev);
56
			skb_reset_mac_header(skb);
Linus Torvalds's avatar
Linus Torvalds committed
57 58 59 60 61 62 63 64 65
		}
		break;
	}
#endif
	case ARPHRD_ETHER:
	case ARPHRD_LOOPBACK: {
		unsigned short len = skb->len;
		struct ethhdr *eth;

66 67
		skb_push(skb, sizeof(*eth));
		skb_reset_mac_header(skb);
Linus Torvalds's avatar
Linus Torvalds committed
68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103
		eth = eth_hdr(skb);
		eth->h_proto = htons(len);
		memcpy(eth->h_dest, da, ETH_ALEN);
		memcpy(eth->h_source, sa, ETH_ALEN);
		break;
	}
	default:
		printk(KERN_WARNING "device type not supported: %d\n",
		       skb->dev->type);
		rc = -EINVAL;
	}
	return rc;
}

/**
 *	llc_build_and_send_ui_pkt - unitdata request interface for upper layers
 *	@sap: sap to use
 *	@skb: packet to send
 *	@dmac: destination mac address
 *	@dsap: destination sap
 *
 *	Upper layers calls this function when upper layer wants to send data
 *	using connection-less mode communication (UI pdu).
 *
 *	Accept data frame from network layer to be sent using connection-
 *	less mode communication; timeout/retries handled by network layer;
 *	package primitive as an event and send to SAP event handler
 */
int llc_build_and_send_ui_pkt(struct llc_sap *sap, struct sk_buff *skb,
			      unsigned char *dmac, unsigned char dsap)
{
	int rc;
	llc_pdu_header_init(skb, LLC_PDU_TYPE_U, sap->laddr.lsap,
			    dsap, LLC_PDU_CMD);
	llc_pdu_init_as_ui_cmd(skb);
	rc = llc_mac_hdr_init(skb, skb->dev->dev_addr, dmac);
104
	if (likely(!rc))
Linus Torvalds's avatar
Linus Torvalds committed
105 106 107 108 109 110
		rc = dev_queue_xmit(skb);
	return rc;
}

EXPORT_SYMBOL(llc_mac_hdr_init);
EXPORT_SYMBOL(llc_build_and_send_ui_pkt);