linux/net/llc/llc_output.c

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/*
* 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);