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 * HIPPI-type device handling.
7 *
8 * Version: @(#)hippi.c 1.0.0 05/29/97
9 *
10 * Authors: Ross Biro, <bir7@leland.Stanford.Edu>
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Mark Evans, <evansmp@uhura.aston.ac.uk>
13 * Florian La Roche, <rzsfl@rz.uni-sb.de>
14 * Alan Cox, <gw4pts@gw4pts.ampr.org>
15 * Jes Sorensen, <Jes.Sorensen@cern.ch>
16 *
17 * This program is free software; you can redistribute it and/or
18 * modify it under the terms of the GNU General Public License
19 * as published by the Free Software Foundation; either version
20 * 2 of the License, or (at your option) any later version.
21 */
22
23 #include <linux/types.h>
24 #include <linux/kernel.h>
25 #include <linux/sched.h>
26 #include <linux/string.h>
27 #include <linux/mm.h>
28 #include <linux/socket.h>
29 #include <linux/in.h>
30 #include <linux/inet.h>
31 #include <linux/netdevice.h>
32 #include <linux/hippidevice.h>
33 #include <linux/skbuff.h>
34 #include <linux/errno.h>
35 #include <net/arp.h>
36 #include <net/sock.h>
37 #include <asm/uaccess.h>
38 #include <asm/checksum.h>
39 #include <asm/segment.h>
40 #include <asm/system.h>
41
42 /*
43 * hippi_net_init()
44 *
45 * Do nothing, this is just to pursuade the stupid linker to behave.
46 */
47
hippi_net_init(void)48 void hippi_net_init(void)
49 {
50 return;
51 }
52
53 /*
54 * Create the HIPPI MAC header for an arbitrary protocol layer
55 *
56 * saddr=NULL means use device source address
57 * daddr=NULL means leave destination address (eg unresolved arp)
58 */
59
hippi_header(struct sk_buff * skb,struct net_device * dev,unsigned short type,void * daddr,void * saddr,unsigned len)60 int hippi_header(struct sk_buff *skb, struct net_device *dev,
61 unsigned short type, void *daddr, void *saddr,
62 unsigned len)
63 {
64 struct hippi_hdr *hip = (struct hippi_hdr *)skb_push(skb, HIPPI_HLEN);
65
66 if (!len){
67 len = skb->len - HIPPI_HLEN;
68 printk("hippi_header(): length not supplied\n");
69 }
70
71 /*
72 * Due to the stupidity of the little endian byte-order we
73 * have to set the fp field this way.
74 */
75 hip->fp.fixed = __constant_htonl(0x04800018);
76 hip->fp.d2_size = htonl(len + 8);
77 hip->le.fc = 0;
78 hip->le.double_wide = 0; /* only HIPPI 800 for the time being */
79 hip->le.message_type = 0; /* Data PDU */
80
81 hip->le.dest_addr_type = 2; /* 12 bit SC address */
82 hip->le.src_addr_type = 2; /* 12 bit SC address */
83
84 memcpy(hip->le.src_switch_addr, dev->dev_addr + 3, 3);
85 memset(&hip->le.reserved, 0, 16);
86
87 hip->snap.dsap = HIPPI_EXTENDED_SAP;
88 hip->snap.ssap = HIPPI_EXTENDED_SAP;
89 hip->snap.ctrl = HIPPI_UI_CMD;
90 hip->snap.oui[0] = 0x00;
91 hip->snap.oui[1] = 0x00;
92 hip->snap.oui[2] = 0x00;
93 hip->snap.ethertype = htons(type);
94
95 if (daddr)
96 {
97 memcpy(hip->le.dest_switch_addr, daddr + 3, 3);
98 memcpy(&skb->private.ifield, daddr + 2, 4);
99 return HIPPI_HLEN;
100 }
101 return -((int)HIPPI_HLEN);
102 }
103
104
105 /*
106 * Rebuild the HIPPI MAC header. This is called after an ARP has
107 * completed on this sk_buff. We now let ARP fill in the other fields.
108 */
109
hippi_rebuild_header(struct sk_buff * skb)110 int hippi_rebuild_header(struct sk_buff *skb)
111 {
112 struct hippi_hdr *hip = (struct hippi_hdr *)skb->data;
113
114 /*
115 * Only IP is currently supported
116 */
117
118 if(hip->snap.ethertype != __constant_htons(ETH_P_IP))
119 {
120 printk(KERN_DEBUG "%s: unable to resolve type %X addresses.\n",skb->dev->name,ntohs(hip->snap.ethertype));
121 return 0;
122 }
123
124 /*
125 * We don't support dynamic ARP on HIPPI, but we use the ARP
126 * static ARP tables to hold the I-FIELDs.
127 */
128 return arp_find(hip->le.daddr, skb);
129 }
130
131
132 /*
133 * Determine the packet's protocol ID.
134 */
135
hippi_type_trans(struct sk_buff * skb,struct net_device * dev)136 unsigned short hippi_type_trans(struct sk_buff *skb, struct net_device *dev)
137 {
138 struct hippi_hdr *hip;
139
140 hip = (struct hippi_hdr *) skb->data;
141
142 /*
143 * This is actually wrong ... question is if we really should
144 * set the raw address here.
145 */
146 skb->mac.raw = skb->data;
147 skb_pull(skb, HIPPI_HLEN);
148
149 /*
150 * No fancy promisc stuff here now.
151 */
152
153 return hip->snap.ethertype;
154 }
155