all repos — cryptopals-challenges @ 5e51d25c8a19a816f6f7bdea33ffc1db63860f80

cryptopals-challenges

set1/src/fixed-xor.c

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#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>

/*
void fixed_xor_stream(uint8_t *key, size_t key_len)
{
	//
}
*/

void fixed_xor(const uint8_t *data, const size_t data_len,
               const uint8_t key)
{
	uint8_t c;
	size_t i;

	for (i = 0; i < data_len; ++i) {
		c = data[i] ^ key;
		putchar(c);
	}
}

int main()
{
	uint8_t data[] = "\x1c\x01\x11\x00\x1f\x01\x01\x00\x06\x1a\x02\x4b\x53"
	                 "\x53\x50\x09\x18\x1c\x00\x00\x00\x00\x00\x00\x00";
	/* // above array XOR'd by 0x41
	uint8_t data[] = "\x5d\x40\x50\x41\x5e\x40\x40\x41\x47\x5b\x43\x0a\x12"
	                 "\x12\x11\x48\x59\x5d\x41\x41\x41\x41\x41\x41\x41";
	*/
	uint8_t key = 0x41;

	fixed_xor(data, sizeof(data)-1, key);

	return EXIT_SUCCESS;
}