canary/djCTF-1

canary/djCTF-1/djctf1.c

@@ -0,0 +1,41 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+void pwnable();
+void init();
+__attribute__((aligned(0x100)))
+void flag(){
+    asm volatile(".byte 0x90");
+    asm volatile(".byte 0x90");
+    asm volatile(".byte 0x90");
+    asm volatile(".byte 0x90");
+    asm volatile(".byte 0x90");
+    asm volatile(".byte 0x90");
+    asm volatile(".byte 0x90");
+    asm volatile(".byte 0x90");
+    asm volatile(".byte 0x90");
+    asm volatile(".byte 0x90");
+    system("cat flag");
+    write(1, "Unbelieveable! You must be an experienced hacker!!\n", 51);
+    write(1, "That's your reward!!", 20);
+}
+int main(){
+    init();
+    write(1, "You are so lucky to have unlimited chance!!! xm!!!\n", 51);
+    while(1){
+        pwnable();
+    }
+}
+void init(){
+    setvbuf(stdout, 0LL, 2, 0LL);
+    setvbuf(stdin, 0LL, 2, 0LL);
+    setvbuf(stderr, 0LL, 2, 0LL);
+}
+void pwnable(){
+    char buf[0x10];
+    write(1, "> ", 2);
+    read(0, buf, 0x29);
+    write(1, "Let's check if you are successful. \n", 36);
+    puts(buf);
+    buf[0x18] = 0x00;
+}