1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * llc_output.c - LLC minimal output path
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright (c) 1997 by Procom Technology, Inc.
6*4882a593Smuzhiyun * 2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
7*4882a593Smuzhiyun */
8*4882a593Smuzhiyun
9*4882a593Smuzhiyun #include <linux/if_arp.h>
10*4882a593Smuzhiyun #include <linux/netdevice.h>
11*4882a593Smuzhiyun #include <linux/skbuff.h>
12*4882a593Smuzhiyun #include <linux/export.h>
13*4882a593Smuzhiyun #include <net/llc.h>
14*4882a593Smuzhiyun #include <net/llc_pdu.h>
15*4882a593Smuzhiyun
16*4882a593Smuzhiyun /**
17*4882a593Smuzhiyun * llc_mac_hdr_init - fills MAC header fields
18*4882a593Smuzhiyun * @skb: Address of the frame to initialize its MAC header
19*4882a593Smuzhiyun * @sa: The MAC source address
20*4882a593Smuzhiyun * @da: The MAC destination address
21*4882a593Smuzhiyun *
22*4882a593Smuzhiyun * Fills MAC header fields, depending on MAC type. Returns 0, If MAC type
23*4882a593Smuzhiyun * is a valid type and initialization completes correctly 1, otherwise.
24*4882a593Smuzhiyun */
llc_mac_hdr_init(struct sk_buff * skb,const unsigned char * sa,const unsigned char * da)25*4882a593Smuzhiyun int llc_mac_hdr_init(struct sk_buff *skb,
26*4882a593Smuzhiyun const unsigned char *sa, const unsigned char *da)
27*4882a593Smuzhiyun {
28*4882a593Smuzhiyun int rc = -EINVAL;
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun switch (skb->dev->type) {
31*4882a593Smuzhiyun case ARPHRD_ETHER:
32*4882a593Smuzhiyun case ARPHRD_LOOPBACK:
33*4882a593Smuzhiyun rc = dev_hard_header(skb, skb->dev, ETH_P_802_2, da, sa,
34*4882a593Smuzhiyun skb->len);
35*4882a593Smuzhiyun if (rc > 0)
36*4882a593Smuzhiyun rc = 0;
37*4882a593Smuzhiyun break;
38*4882a593Smuzhiyun default:
39*4882a593Smuzhiyun break;
40*4882a593Smuzhiyun }
41*4882a593Smuzhiyun return rc;
42*4882a593Smuzhiyun }
43*4882a593Smuzhiyun
44*4882a593Smuzhiyun /**
45*4882a593Smuzhiyun * llc_build_and_send_ui_pkt - unitdata request interface for upper layers
46*4882a593Smuzhiyun * @sap: sap to use
47*4882a593Smuzhiyun * @skb: packet to send
48*4882a593Smuzhiyun * @dmac: destination mac address
49*4882a593Smuzhiyun * @dsap: destination sap
50*4882a593Smuzhiyun *
51*4882a593Smuzhiyun * Upper layers calls this function when upper layer wants to send data
52*4882a593Smuzhiyun * using connection-less mode communication (UI pdu).
53*4882a593Smuzhiyun *
54*4882a593Smuzhiyun * Accept data frame from network layer to be sent using connection-
55*4882a593Smuzhiyun * less mode communication; timeout/retries handled by network layer;
56*4882a593Smuzhiyun * package primitive as an event and send to SAP event handler
57*4882a593Smuzhiyun */
llc_build_and_send_ui_pkt(struct llc_sap * sap,struct sk_buff * skb,unsigned char * dmac,unsigned char dsap)58*4882a593Smuzhiyun int llc_build_and_send_ui_pkt(struct llc_sap *sap, struct sk_buff *skb,
59*4882a593Smuzhiyun unsigned char *dmac, unsigned char dsap)
60*4882a593Smuzhiyun {
61*4882a593Smuzhiyun int rc;
62*4882a593Smuzhiyun llc_pdu_header_init(skb, LLC_PDU_TYPE_U, sap->laddr.lsap,
63*4882a593Smuzhiyun dsap, LLC_PDU_CMD);
64*4882a593Smuzhiyun llc_pdu_init_as_ui_cmd(skb);
65*4882a593Smuzhiyun rc = llc_mac_hdr_init(skb, skb->dev->dev_addr, dmac);
66*4882a593Smuzhiyun if (likely(!rc))
67*4882a593Smuzhiyun rc = dev_queue_xmit(skb);
68*4882a593Smuzhiyun else
69*4882a593Smuzhiyun kfree_skb(skb);
70*4882a593Smuzhiyun return rc;
71*4882a593Smuzhiyun }
72*4882a593Smuzhiyun
73*4882a593Smuzhiyun EXPORT_SYMBOL(llc_mac_hdr_init);
74*4882a593Smuzhiyun EXPORT_SYMBOL(llc_build_and_send_ui_pkt);
75