Timing Attack

attack.c

#include <stdio.h>
#include <sys/time.h>
#include <stdint.h>
#include <string.h>
#include <math.h>

// http://www.kernel.org/doc/man-pages/online/pages/man2/clock_gettime.2.html

uint64_t microtime() {
    struct timeval start;
    struct timezone tz;
    gettimeofday(&start, &tz);
    return (((uint64_t) start.tv_sec) * 1000000) + (uint64_t) start.tv_usec;
}

int main(int argc, char** argv) {
    unsigned int i, temp;
    uint64_t start, end;

    start = microtime();

    start = microtime();
    for (i = 0; i < 0xfffffff; i += 1) {
        strncmp("HELLO", "WORLD", 5);
    }
    end = microtime() - start;
    printf("Time: %llu\n", end);

    start = microtime();
    for (i = 0; i < 0xfffffff; i += 1) {
        strncmp("HELLO", "HELLO", 5);
    }
    end = microtime() - start;
    printf("Time: %llu\n", end);

    return 0;
}

attack.js

var iters = 0xffffff,
    trials = 100,
    test = '5ca2c015b57a74e28d4aae6a154b489368922827';

function attack(str) {
    var start, i, temp;
    start = new Date().getTime();
    for (i = 0; i < iters; i += 1) {
        temp = (test === str);
    }
    return new Date().getTime() - start;
}

var testers = [
    '516bee79283014470271832d34d4db7990283466', // good
    '6e18e5a4a7dee589bce20ff39a87ecbd53db55d9',
    '9fd1911878d91e4835b402c75ab62f7360162359'
];

var tests = (function () {
    var i, tests = [];
    for (i = 0; i < trials; i += 1) {
        tests.push(testers.map(attack));
    }
    return tests;
}()).reduce(function (a, b) {
    return [a[0] + b[0], a[1] + b[1], a[2] + b[2]];
});

console.log('match time     ', tests[0]);
console.log('no match #1 time', tests[1]);
console.log('no match #2 time', tests[2]);