1 /*
2 * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
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 as
6 * published by the Free Software Foundation; either version 2 of the
7 * License, or any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
17 */
18
19 FILE_LICENCE ( GPL2_OR_LATER );
20
21 #include <stdint.h>
22 #include <stdio.h>
23 #include <string.h>
24 #include <byteswap.h>
25 #include <errno.h>
26 #include <assert.h>
27 #include <gpxe/if_arp.h>
28 #include <gpxe/if_ether.h>
29 #include <gpxe/in.h>
30 #include <gpxe/netdevice.h>
31 #include <gpxe/iobuf.h>
32 #include <gpxe/ethernet.h>
33
34 /** @file
35 *
36 * Ethernet protocol
37 *
38 */
39
40 /** Ethernet broadcast MAC address */
41 static uint8_t eth_broadcast[ETH_ALEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
42
43 /**
44 * Add Ethernet link-layer header
45 *
46 * @v netdev Network device
47 * @v iobuf I/O buffer
48 * @v ll_dest Link-layer destination address
49 * @v ll_source Source link-layer address
50 * @v net_proto Network-layer protocol, in network-byte order
51 * @ret rc Return status code
52 */
eth_push(struct net_device * netdev __unused,struct io_buffer * iobuf,const void * ll_dest,const void * ll_source,uint16_t net_proto)53 static int eth_push ( struct net_device *netdev __unused,
54 struct io_buffer *iobuf, const void *ll_dest,
55 const void *ll_source, uint16_t net_proto ) {
56 struct ethhdr *ethhdr = iob_push ( iobuf, sizeof ( *ethhdr ) );
57
58 /* Build Ethernet header */
59 memcpy ( ethhdr->h_dest, ll_dest, ETH_ALEN );
60 memcpy ( ethhdr->h_source, ll_source, ETH_ALEN );
61 ethhdr->h_protocol = net_proto;
62
63 return 0;
64 }
65
66 /**
67 * Remove Ethernet link-layer header
68 *
69 * @v netdev Network device
70 * @v iobuf I/O buffer
71 * @ret ll_dest Link-layer destination address
72 * @ret ll_source Source link-layer address
73 * @ret net_proto Network-layer protocol, in network-byte order
74 * @ret rc Return status code
75 */
eth_pull(struct net_device * netdev __unused,struct io_buffer * iobuf,const void ** ll_dest,const void ** ll_source,uint16_t * net_proto)76 static int eth_pull ( struct net_device *netdev __unused,
77 struct io_buffer *iobuf, const void **ll_dest,
78 const void **ll_source, uint16_t *net_proto ) {
79 struct ethhdr *ethhdr = iobuf->data;
80
81 /* Sanity check */
82 if ( iob_len ( iobuf ) < sizeof ( *ethhdr ) ) {
83 DBG ( "Ethernet packet too short (%zd bytes)\n",
84 iob_len ( iobuf ) );
85 return -EINVAL;
86 }
87
88 /* Strip off Ethernet header */
89 iob_pull ( iobuf, sizeof ( *ethhdr ) );
90
91 /* Fill in required fields */
92 *ll_dest = ethhdr->h_dest;
93 *ll_source = ethhdr->h_source;
94 *net_proto = ethhdr->h_protocol;
95
96 return 0;
97 }
98
99 /**
100 * Initialise Ethernet address
101 *
102 * @v hw_addr Hardware address
103 * @v ll_addr Link-layer address
104 */
eth_init_addr(const void * hw_addr,void * ll_addr)105 void eth_init_addr ( const void *hw_addr, void *ll_addr ) {
106 memcpy ( ll_addr, hw_addr, ETH_ALEN );
107 }
108
109 /**
110 * Transcribe Ethernet address
111 *
112 * @v ll_addr Link-layer address
113 * @ret string Link-layer address in human-readable format
114 */
eth_ntoa(const void * ll_addr)115 const char * eth_ntoa ( const void *ll_addr ) {
116 static char buf[18]; /* "00:00:00:00:00:00" */
117 const uint8_t *eth_addr = ll_addr;
118
119 sprintf ( buf, "%02x:%02x:%02x:%02x:%02x:%02x",
120 eth_addr[0], eth_addr[1], eth_addr[2],
121 eth_addr[3], eth_addr[4], eth_addr[5] );
122 return buf;
123 }
124
125 /**
126 * Hash multicast address
127 *
128 * @v af Address family
129 * @v net_addr Network-layer address
130 * @v ll_addr Link-layer address to fill in
131 * @ret rc Return status code
132 */
eth_mc_hash(unsigned int af,const void * net_addr,void * ll_addr)133 int eth_mc_hash ( unsigned int af, const void *net_addr, void *ll_addr ) {
134 const uint8_t *net_addr_bytes = net_addr;
135 uint8_t *ll_addr_bytes = ll_addr;
136
137 switch ( af ) {
138 case AF_INET:
139 ll_addr_bytes[0] = 0x01;
140 ll_addr_bytes[1] = 0x00;
141 ll_addr_bytes[2] = 0x5e;
142 ll_addr_bytes[3] = net_addr_bytes[1] & 0x7f;
143 ll_addr_bytes[4] = net_addr_bytes[2];
144 ll_addr_bytes[5] = net_addr_bytes[3];
145 return 0;
146 default:
147 return -ENOTSUP;
148 }
149 }
150
151 /**
152 * Generate Ethernet-compatible compressed link-layer address
153 *
154 * @v ll_addr Link-layer address
155 * @v eth_addr Ethernet-compatible address to fill in
156 */
eth_eth_addr(const void * ll_addr,void * eth_addr)157 int eth_eth_addr ( const void *ll_addr, void *eth_addr ) {
158 memcpy ( eth_addr, ll_addr, ETH_ALEN );
159 return 0;
160 }
161
162 /** Ethernet protocol */
163 struct ll_protocol ethernet_protocol __ll_protocol = {
164 .name = "Ethernet",
165 .ll_proto = htons ( ARPHRD_ETHER ),
166 .hw_addr_len = ETH_ALEN,
167 .ll_addr_len = ETH_ALEN,
168 .ll_header_len = ETH_HLEN,
169 .push = eth_push,
170 .pull = eth_pull,
171 .init_addr = eth_init_addr,
172 .ntoa = eth_ntoa,
173 .mc_hash = eth_mc_hash,
174 .eth_addr = eth_eth_addr,
175 };
176
177 /**
178 * Allocate Ethernet device
179 *
180 * @v priv_size Size of driver private data
181 * @ret netdev Network device, or NULL
182 */
alloc_etherdev(size_t priv_size)183 struct net_device * alloc_etherdev ( size_t priv_size ) {
184 struct net_device *netdev;
185
186 netdev = alloc_netdev ( priv_size );
187 if ( netdev ) {
188 netdev->ll_protocol = ðernet_protocol;
189 netdev->ll_broadcast = eth_broadcast;
190 netdev->max_pkt_len = ETH_FRAME_LEN;
191 }
192 return netdev;
193 }
194