exploitable.c

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <errno.h>
#include <unistd.h>
#include <sys/types.h>

#define SECRET_PHRASE "bed bananas"
#define SECRET_FILE "./secret.txt"

void win() {
    FILE *fd = fopen(SECRET_FILE, "r");
    if (fd == 0) {
        perror(SECRET_FILE);
        return;
    }
    fseek(fd, 0, SEEK_END);
    long sz = ftell(fd);
    fseek(fd, 0, SEEK_SET);
    char *buf = malloc(sz+1);
    fread(buf, sz, 1, fd);
    buf[sz] = 0;
    printf("%s\n", buf);
    return;
}

int main(int argc, char **argv) {
    char pass[12] = {0};
    printf("What is the secret phrase?\n");
    // scanf("11%[^\n]", pass);
    scanf("%[^\n]", pass);
    if (0 == (strncmp(SECRET_PHRASE, pass, sizeof(SECRET_PHRASE)))) {
        win();
    } else {
        printf("The secret phrase is not: %s\n", pass);
    }
    return 0;
}