1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun * (C) Copyright 2016
3*4882a593Smuzhiyun * Olliver Schinagl <oliver@schinagl.nl>
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * SPDX-License-Identifier: GPL-2.0+
6*4882a593Smuzhiyun */
7*4882a593Smuzhiyun
8*4882a593Smuzhiyun #include <ctype.h>
9*4882a593Smuzhiyun #include <stdbool.h>
10*4882a593Smuzhiyun #include <stdint.h>
11*4882a593Smuzhiyun #include <stdio.h>
12*4882a593Smuzhiyun #include <stdlib.h>
13*4882a593Smuzhiyun #include <string.h>
14*4882a593Smuzhiyun #include <u-boot/crc.h>
15*4882a593Smuzhiyun
16*4882a593Smuzhiyun #define ARP_HLEN 6 /* Length of hardware address */
17*4882a593Smuzhiyun #define ARP_HLEN_ASCII (ARP_HLEN * 2) + (ARP_HLEN - 1) /* with separators */
18*4882a593Smuzhiyun #define ARP_HLEN_LAZY (ARP_HLEN * 2) /* separatorless hardware address length */
19*4882a593Smuzhiyun
nibble_to_hex(const char * nibble,bool lo)20*4882a593Smuzhiyun uint8_t nibble_to_hex(const char *nibble, bool lo)
21*4882a593Smuzhiyun {
22*4882a593Smuzhiyun return (strtol(nibble, NULL, 16) << (lo ? 0 : 4)) & (lo ? 0x0f : 0xf0);
23*4882a593Smuzhiyun }
24*4882a593Smuzhiyun
process_mac(const char * mac_address)25*4882a593Smuzhiyun int process_mac(const char *mac_address)
26*4882a593Smuzhiyun {
27*4882a593Smuzhiyun uint8_t ethaddr[ARP_HLEN + 1] = { 0x00 };
28*4882a593Smuzhiyun uint_fast8_t i = 0;
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun while (*mac_address != '\0') {
31*4882a593Smuzhiyun char nibble[2] = { 0x00, '\n' }; /* for strtol */
32*4882a593Smuzhiyun
33*4882a593Smuzhiyun nibble[0] = *mac_address++;
34*4882a593Smuzhiyun if (isxdigit(nibble[0])) {
35*4882a593Smuzhiyun if (isupper(nibble[0]))
36*4882a593Smuzhiyun nibble[0] = tolower(nibble[0]);
37*4882a593Smuzhiyun ethaddr[i >> 1] |= nibble_to_hex(nibble, (i % 2) != 0);
38*4882a593Smuzhiyun i++;
39*4882a593Smuzhiyun }
40*4882a593Smuzhiyun }
41*4882a593Smuzhiyun
42*4882a593Smuzhiyun for (i = 0; i < ARP_HLEN; i++)
43*4882a593Smuzhiyun printf("%.2x", ethaddr[i]);
44*4882a593Smuzhiyun printf("%.2x\n", crc8(0, ethaddr, ARP_HLEN));
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun return 0;
47*4882a593Smuzhiyun }
48*4882a593Smuzhiyun
print_usage(char * cmdname)49*4882a593Smuzhiyun void print_usage(char *cmdname)
50*4882a593Smuzhiyun {
51*4882a593Smuzhiyun printf("Usage: %s <mac_address>\n", cmdname);
52*4882a593Smuzhiyun puts("<mac_address> may be with or without separators.");
53*4882a593Smuzhiyun puts("Valid seperators are ':' and '-'.");
54*4882a593Smuzhiyun puts("<mac_address> digits are in base 16.\n");
55*4882a593Smuzhiyun }
56*4882a593Smuzhiyun
main(int argc,char * argv[])57*4882a593Smuzhiyun int main(int argc, char *argv[])
58*4882a593Smuzhiyun {
59*4882a593Smuzhiyun if (argc < 2) {
60*4882a593Smuzhiyun print_usage(argv[0]);
61*4882a593Smuzhiyun return 1;
62*4882a593Smuzhiyun }
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun if (!((strlen(argv[1]) == ARP_HLEN_ASCII) || (strlen(argv[1]) == ARP_HLEN_LAZY))) {
65*4882a593Smuzhiyun puts("The MAC address is not valid.\n");
66*4882a593Smuzhiyun print_usage(argv[0]);
67*4882a593Smuzhiyun return 1;
68*4882a593Smuzhiyun }
69*4882a593Smuzhiyun
70*4882a593Smuzhiyun if (process_mac(argv[1])) {
71*4882a593Smuzhiyun puts("Failed to calculate the MAC's checksum.");
72*4882a593Smuzhiyun return 1;
73*4882a593Smuzhiyun }
74*4882a593Smuzhiyun
75*4882a593Smuzhiyun return 0;
76*4882a593Smuzhiyun }
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