rapid7/metasploit-framework

/*
 * Outputs the value of time(2) with the 16 least significant bits zeroed out.
 * For use in context keyed payload encoding.
 *
 * Author: Dimitris Glynos <dimitris at census-labs.com>
 */

#include <stdlib.h>
#include <stdio.h>
#define __USE_XOPEN
#include <time.h>

char *app = NULL;

void croak_usage(void)
{
    fprintf(stderr, "usage: %s [date & time]\n"
        "\tSupported date & time format: 'YYYY-MM-DD HH:MM:SS'\n"
        "\te.g. %s '2003-11-04 14:23:10'\n",
        app, app);
    exit(1);
}

time_t parse_time(const char *input)
{
    struct tm t;
    char *p;

    p = strptime(input, "%Y-%m-%d %H:%M:%S", &t);

    if ((!p) || (*p != '\0')) {
        fprintf(stderr, "error while processing time spec!\n");
        croak_usage();
    }

    return mktime(&t);
}

int main(int argc, char *argv[])
{
    time_t t;

    app = argv[0];

    if (argc > 2)
        croak_usage();

    if (argc == 2) 
        t = parse_time(argv[1]);
    else 
        t = time(NULL);

    printf("%#.8lx\n", t & 0xffff0000);
    return 0;
}