1/*-
2 * Copyright (c) 2015, Adrian Chadd <adrian@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice unmodified, this list of conditions, and the following
10 *    disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28#include <sys/cdefs.h>
29__FBSDID("$FreeBSD$");
30
31#include <sys/param.h>
32#include <sys/systm.h>
33#include <sys/types.h>
34#include <sys/libkern.h>
35
36#include <net/ethernet.h>
37
38#include <mips/atheros/ar71xx_macaddr.h>
39
40/*
41 * Some boards don't have a separate MAC address for each individual
42 * device on-board, but instead need to derive them from a single MAC
43 * address stored somewhere.
44 */
45uint8_t ar71xx_board_mac_addr[ETHER_ADDR_LEN];
46
47/*
48 * Initialise a MAC address 'dst' from a MAC address 'src'.
49 *
50 * 'offset' is added to the low three bytes to allow for sequential
51 * MAC addresses to be derived from a single one.
52 *
53 * 'is_local' is whether this 'dst' should be made a local MAC address.
54 *
55 * Returns 0 if it was successfully initialised, -1 on error.
56 */
57int
58ar71xx_mac_addr_init(unsigned char *dst, const unsigned char *src,
59    int offset, int is_local)
60{
61	int t;
62
63	if (dst == NULL || src == NULL)
64		return (-1);
65
66	/* XXX TODO: validate 'src' is a valid MAC address */
67
68	t = (((uint32_t) src[3]) << 16)
69	    + (((uint32_t) src[4]) << 8)
70	    + ((uint32_t) src[5]);
71
72	/* Note: this is handles both positive and negative offsets */
73	t += offset;
74
75	dst[0] = src[0];
76	dst[1] = src[1];
77	dst[2] = src[2];
78	dst[3] = (t >> 16) & 0xff;
79	dst[4] = (t >> 8) & 0xff;
80	dst[5] = t & 0xff;
81
82	if (is_local)
83		dst[0] |= 0x02;
84
85	/* Everything's okay */
86	return (0);
87}
88
89/*
90 * Initialise a random MAC address for use by if_arge.c and whatever
91 * else requires it.
92 *
93 * Returns 0 on success, -1 on error.
94 */
95int
96ar71xx_mac_addr_random_init(unsigned char *dst)
97{
98	uint32_t rnd;
99
100	rnd = arc4random();
101
102	dst[0] = 'b';
103	dst[1] = 's';
104	dst[2] = 'd';
105	dst[3] = (rnd >> 24) & 0xff;
106	dst[4] = (rnd >> 16) & 0xff;
107	dst[5] = (rnd >> 8) & 0xff;
108
109	return (0);
110}
111