root/net/llc/llc_output.c

DEFINITIONS

1. llc_mac_hdr_init
2. llc_build_and_send_ui_pkt

/*
 * 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.
 */
int llc_mac_hdr_init(struct sk_buff *skb,
                     const unsigned char *sa, const unsigned char *da)
{
        int rc = 0;

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

                skb_push(skb, sizeof(*trh));
                skb_reset_mac_header(skb);
                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);
                        skb_reset_mac_header(skb);
                }
                break;
        }
#endif
        case ARPHRD_ETHER:
        case ARPHRD_LOOPBACK: {
                unsigned short len = skb->len;
                struct ethhdr *eth;

                skb_push(skb, sizeof(*eth));
                skb_reset_mac_header(skb);
                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);
        if (likely(!rc))
                rc = dev_queue_xmit(skb);
        return rc;
}

EXPORT_SYMBOL(llc_mac_hdr_init);
EXPORT_SYMBOL(llc_build_and_send_ui_pkt);