1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * FDDI-type device handling.
7 *
8 * Version: @(#)fddi.c 1.0.0 08/12/96
9 *
10 * Authors: Lawrence V. Stefani, <stefani@lkg.dec.com>
11 *
12 * fddi.c is based on previous eth.c and tr.c work by
13 * Ross Biro, <bir7@leland.Stanford.Edu>
14 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
15 * Mark Evans, <evansmp@uhura.aston.ac.uk>
16 * Florian La Roche, <rzsfl@rz.uni-sb.de>
17 * Alan Cox, <gw4pts@gw4pts.ampr.org>
18 *
19 * This program is free software; you can redistribute it and/or
20 * modify it under the terms of the GNU General Public License
21 * as published by the Free Software Foundation; either version
22 * 2 of the License, or (at your option) any later version.
23 *
24 * Changes
25 * Alan Cox : New arp/rebuild header
26 * Maciej W. Rozycki : IPv6 support
27 */
28
29 #include <linux/config.h>
30 #include <asm/segment.h>
31 #include <asm/system.h>
32 #include <linux/types.h>
33 #include <linux/kernel.h>
34 #include <linux/sched.h>
35 #include <linux/string.h>
36 #include <linux/mm.h>
37 #include <linux/socket.h>
38 #include <linux/in.h>
39 #include <linux/inet.h>
40 #include <linux/netdevice.h>
41 #include <linux/fddidevice.h>
42 #include <linux/if_ether.h>
43 #include <linux/skbuff.h>
44 #include <linux/errno.h>
45 #include <net/arp.h>
46 #include <net/sock.h>
47
48 /*
49 * Create the FDDI MAC header for an arbitrary protocol layer
50 *
51 * saddr=NULL means use device source address
52 * daddr=NULL means leave destination address (eg unresolved arp)
53 */
54
fddi_header(struct sk_buff * skb,struct net_device * dev,unsigned short type,void * daddr,void * saddr,unsigned len)55 int fddi_header(struct sk_buff *skb, struct net_device *dev, unsigned short type,
56 void *daddr, void *saddr, unsigned len)
57 {
58 int hl = FDDI_K_SNAP_HLEN;
59 struct fddihdr *fddi;
60
61 if(type != ETH_P_IP && type != ETH_P_IPV6 && type != ETH_P_ARP)
62 hl=FDDI_K_8022_HLEN-3;
63 fddi = (struct fddihdr *)skb_push(skb, hl);
64 fddi->fc = FDDI_FC_K_ASYNC_LLC_DEF;
65 if(type == ETH_P_IP || type == ETH_P_IPV6 || type == ETH_P_ARP)
66 {
67 fddi->hdr.llc_snap.dsap = FDDI_EXTENDED_SAP;
68 fddi->hdr.llc_snap.ssap = FDDI_EXTENDED_SAP;
69 fddi->hdr.llc_snap.ctrl = FDDI_UI_CMD;
70 fddi->hdr.llc_snap.oui[0] = 0x00;
71 fddi->hdr.llc_snap.oui[1] = 0x00;
72 fddi->hdr.llc_snap.oui[2] = 0x00;
73 fddi->hdr.llc_snap.ethertype = htons(type);
74 }
75
76 /* Set the source and destination hardware addresses */
77
78 if (saddr != NULL)
79 memcpy(fddi->saddr, saddr, dev->addr_len);
80 else
81 memcpy(fddi->saddr, dev->dev_addr, dev->addr_len);
82
83 if (daddr != NULL)
84 {
85 memcpy(fddi->daddr, daddr, dev->addr_len);
86 return(hl);
87 }
88
89 return(-hl);
90 }
91
92
93 /*
94 * Rebuild the FDDI MAC header. This is called after an ARP
95 * (or in future other address resolution) has completed on
96 * this sk_buff. We now let ARP fill in the other fields.
97 */
98
fddi_rebuild_header(struct sk_buff * skb)99 int fddi_rebuild_header(struct sk_buff *skb)
100 {
101 struct fddihdr *fddi = (struct fddihdr *)skb->data;
102
103 #ifdef CONFIG_INET
104 if (fddi->hdr.llc_snap.ethertype == __constant_htons(ETH_P_IP))
105 /* Try to get ARP to resolve the header and fill destination address */
106 return arp_find(fddi->daddr, skb);
107 else
108 #endif
109 {
110 printk("%s: Don't know how to resolve type %02X addresses.\n",
111 skb->dev->name, htons(fddi->hdr.llc_snap.ethertype));
112 return(0);
113 }
114 }
115
116
117 /*
118 * Determine the packet's protocol ID and fill in skb fields.
119 * This routine is called before an incoming packet is passed
120 * up. It's used to fill in specific skb fields and to set
121 * the proper pointer to the start of packet data (skb->data).
122 */
123
fddi_type_trans(struct sk_buff * skb,struct net_device * dev)124 unsigned short fddi_type_trans(struct sk_buff *skb, struct net_device *dev)
125 {
126 struct fddihdr *fddi = (struct fddihdr *)skb->data;
127 unsigned short type;
128
129 /*
130 * Set mac.raw field to point to FC byte, set data field to point
131 * to start of packet data. Assume 802.2 SNAP frames for now.
132 */
133
134 skb->mac.raw = skb->data; /* point to frame control (FC) */
135
136 if(fddi->hdr.llc_8022_1.dsap==0xe0)
137 {
138 skb_pull(skb, FDDI_K_8022_HLEN-3);
139 type = __constant_htons(ETH_P_802_2);
140 }
141 else
142 {
143 skb_pull(skb, FDDI_K_SNAP_HLEN); /* adjust for 21 byte header */
144 type=fddi->hdr.llc_snap.ethertype;
145 }
146
147 /* Set packet type based on destination address and flag settings */
148
149 if (*fddi->daddr & 0x01)
150 {
151 if (memcmp(fddi->daddr, dev->broadcast, FDDI_K_ALEN) == 0)
152 skb->pkt_type = PACKET_BROADCAST;
153 else
154 skb->pkt_type = PACKET_MULTICAST;
155 }
156
157 else if (dev->flags & IFF_PROMISC)
158 {
159 if (memcmp(fddi->daddr, dev->dev_addr, FDDI_K_ALEN))
160 skb->pkt_type = PACKET_OTHERHOST;
161 }
162
163 /* Assume 802.2 SNAP frames, for now */
164
165 return(type);
166 }
167