1 /*
2  * NET3:	Fibre Channel device handling subroutines
3  *
4  *		This program is free software; you can redistribute it and/or
5  *		modify it under the terms of the GNU General Public License
6  *		as published by the Free Software Foundation; either version
7  *		2 of the License, or (at your option) any later version.
8  *
9  *		Vineet Abraham <vma@iol.unh.edu>
10  *		v 1.0 03/22/99
11  */
12 
13 #include <linux/config.h>
14 #include <linux/module.h>
15 
16 #include <asm/uaccess.h>
17 #include <asm/system.h>
18 #include <linux/types.h>
19 #include <linux/kernel.h>
20 #include <linux/sched.h>
21 #include <linux/string.h>
22 #include <linux/mm.h>
23 #include <linux/socket.h>
24 #include <linux/in.h>
25 #include <linux/inet.h>
26 #include <linux/netdevice.h>
27 #include <linux/fcdevice.h>
28 #include <linux/skbuff.h>
29 #include <linux/errno.h>
30 #include <linux/timer.h>
31 #include <linux/net.h>
32 #include <linux/proc_fs.h>
33 #include <linux/init.h>
34 #include <net/arp.h>
35 
36 /*
37  *	Put the headers on a Fibre Channel packet.
38  */
39 
fc_header(struct sk_buff * skb,struct net_device * dev,unsigned short type,void * daddr,void * saddr,unsigned len)40 int fc_header(struct sk_buff *skb, struct net_device *dev, unsigned short type,
41               void *daddr, void *saddr, unsigned len)
42 {
43 	struct fch_hdr *fch;
44 	int hdr_len;
45 
46 	/*
47 	 * Add the 802.2 SNAP header if IP as the IPv4 code calls
48 	 * dev->hard_header directly.
49 	 */
50 	if (type == ETH_P_IP || type == ETH_P_ARP)
51 	{
52 		struct fcllc *fcllc=(struct fcllc *)(fch+1);
53 
54 		hdr_len = sizeof(struct fch_hdr) + sizeof(struct fcllc);
55 		fch = (struct fch_hdr *)skb_push(skb, hdr_len);
56 		fcllc = (struct fcllc *)(fch+1);
57 		fcllc->dsap = fcllc->ssap = EXTENDED_SAP;
58 		fcllc->llc = UI_CMD;
59 		fcllc->protid[0] = fcllc->protid[1] = fcllc->protid[2] = 0x00;
60 		fcllc->ethertype = htons(type);
61 	}
62 	else
63 	{
64 		hdr_len = sizeof(struct fch_hdr);
65 		fch = (struct fch_hdr *)skb_push(skb, hdr_len);
66 	}
67 
68 	if(saddr)
69 		memcpy(fch->saddr,saddr,dev->addr_len);
70 	else
71 		memcpy(fch->saddr,dev->dev_addr,dev->addr_len);
72 
73 	if(daddr)
74 	{
75 		memcpy(fch->daddr,daddr,dev->addr_len);
76 		return(hdr_len);
77 	}
78 	return -hdr_len;
79 }
80 
81 /*
82  *	A neighbour discovery of some species (eg arp) has completed. We
83  *	can now send the packet.
84  */
85 
fc_rebuild_header(struct sk_buff * skb)86 int fc_rebuild_header(struct sk_buff *skb)
87 {
88 	struct fch_hdr *fch=(struct fch_hdr *)skb->data;
89 	struct fcllc *fcllc=(struct fcllc *)(skb->data+sizeof(struct fch_hdr));
90 	if(fcllc->ethertype != htons(ETH_P_IP)) {
91 		printk("fc_rebuild_header: Don't know how to resolve type %04X addresses ?\n",(unsigned int)htons(fcllc->ethertype));
92 		return 0;
93 	}
94 #ifdef CONFIG_INET
95 	return arp_find(fch->daddr, skb);
96 #else
97 	return 0;
98 #endif
99 }
100 
101 EXPORT_SYMBOL(fc_type_trans);
102 
103 unsigned short
fc_type_trans(struct sk_buff * skb,struct net_device * dev)104 fc_type_trans(struct sk_buff *skb, struct net_device *dev)
105 {
106 	struct fch_hdr *fch = (struct fch_hdr *)skb->data;
107 	struct fcllc *fcllc;
108 
109 	skb->mac.raw = skb->data;
110 	fcllc = (struct fcllc *)(skb->data + sizeof (struct fch_hdr) + 2);
111 	skb_pull(skb, sizeof (struct fch_hdr) + 2);
112 
113 	if (*fch->daddr & 1) {
114 		if (!memcmp(fch->daddr, dev->broadcast, FC_ALEN))
115 			skb->pkt_type = PACKET_BROADCAST;
116 		else
117 			skb->pkt_type = PACKET_MULTICAST;
118 	} else if (dev->flags & IFF_PROMISC) {
119 		if (memcmp(fch->daddr, dev->dev_addr, FC_ALEN))
120 			skb->pkt_type = PACKET_OTHERHOST;
121 	}
122 
123 	/*
124 	 * Strip the SNAP header from ARP packets since we don't pass
125 	 * them through to the 802.2/SNAP layers.
126 	 */
127 	if (fcllc->dsap == EXTENDED_SAP &&
128 	    (fcllc->ethertype == ntohs(ETH_P_IP) ||
129 	     fcllc->ethertype == ntohs(ETH_P_ARP))) {
130 		skb_pull(skb, sizeof (struct fcllc));
131 		return fcllc->ethertype;
132 	}
133 
134 	return ntohs(ETH_P_802_2);
135 }
136