76 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			76 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0+
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| /*
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|  * (C) Copyright 2016
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|  * Olliver Schinagl <oliver@schinagl.nl>
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|  */
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| 
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| #include <ctype.h>
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| #include <stdbool.h>
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| #include <stdint.h>
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| #include <stdio.h>
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| #include <stdlib.h>
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| #include <string.h>
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| #include <u-boot/crc.h>
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| 
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| #define ARP_HLEN 6 /* Length of hardware address */
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| #define ARP_HLEN_ASCII (ARP_HLEN * 2) + (ARP_HLEN - 1) /* with separators */
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| #define ARP_HLEN_LAZY (ARP_HLEN * 2) /* separatorless hardware address length */
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| 
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| uint8_t nibble_to_hex(const char *nibble, bool lo)
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| {
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| 	return (strtol(nibble, NULL, 16) << (lo ? 0 : 4)) & (lo ? 0x0f : 0xf0);
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| }
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| 
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| int process_mac(const char *mac_address)
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| {
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| 	uint8_t ethaddr[ARP_HLEN + 1] = { 0x00 };
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| 	uint_fast8_t i = 0;
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| 
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| 	while (*mac_address != '\0') {
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| 		char nibble[2] = { 0x00, '\n' }; /* for strtol */
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| 
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| 		nibble[0] = *mac_address++;
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| 		if (isxdigit(nibble[0])) {
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| 			if (isupper(nibble[0]))
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| 				nibble[0] = tolower(nibble[0]);
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| 			ethaddr[i >> 1] |= nibble_to_hex(nibble, (i % 2) != 0);
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| 			i++;
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| 		}
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| 	}
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| 
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| 	for (i = 0; i < ARP_HLEN; i++)
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| 		printf("%.2x", ethaddr[i]);
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| 	printf("%.2x\n", crc8(0, ethaddr, ARP_HLEN));
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| 
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| 	return 0;
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| }
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| 
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| void print_usage(char *cmdname)
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| {
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| 	printf("Usage: %s <mac_address>\n", cmdname);
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| 	puts("<mac_address> may be with or without separators.");
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| 	puts("Valid seperators are ':' and '-'.");
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| 	puts("<mac_address> digits are in base 16.\n");
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| }
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| 
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| int main(int argc, char *argv[])
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| {
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| 	if (argc < 2) {
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| 		print_usage(argv[0]);
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| 		return 1;
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| 	}
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| 
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| 	if (!((strlen(argv[1]) == ARP_HLEN_ASCII) || (strlen(argv[1]) == ARP_HLEN_LAZY))) {
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| 		puts("The MAC address is not valid.\n");
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| 		print_usage(argv[0]);
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| 		return 1;
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| 	}
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| 
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| 	if (process_mac(argv[1])) {
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| 		puts("Failed to calculate the MAC's checksum.");
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| 		return 1;
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| 	}
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| 
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| 	return 0;
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| }
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