-
-
[分享]pwnable.kr BlackJack day10
-
发表于: 2021-1-12 23:01
-
这是一个类似 21 点的游戏。
初始现金是 500，我们输入赌注（bet），如果赌注比拥有的现金（cash）大的数会给错误提示。
现金超过一百万可以看到 flag。
源码过大，已上传至附件。
核心函数有 betting() 和 play()
betting() 是我们下注的函数
可以看到输入 bet 后，没有对 bet 值是否合法做检测，全都返回 bet。
play() 是游戏的核心函数
重点如下
可以看出当我们赢的时候，我们的现金变为现金 + 赌注，输的时候变为现金 - 赌注。
由 betting() 知，赌注的输入没有做足够的限制，所以我们可以输入一个较大负数，然后故意输掉，这样我们的金额会直接超过一百万，达到看见 flag 的要求，继续玩一局即可看到 flag。
红框内为 flag
void play() //Plays game
{ int p=0; // holds value of player_total
int i=1; // counter for asking user to hold or stay (aka game turns)
char choice3;
cash = cash;
cash_test();
printf("\nCash: $%d\n",cash); //Prints amount of cash user has
randcard(); //Generates random card
player_total = p + l; //Computes player total
p = player_total;
printf("\nYour Total is %d\n", p); //Prints player total
dealer(); //Computes and prints dealer total
betting(); //Prompts user to enter bet amount
while(i<=21) //While loop used to keep asking user to hit or stay at most twenty-one times
// because there is a chance user can generate twenty-one consecutive 1's
{
if(p==21) //If user total is 21, win
{
printf("\nUnbelievable! You Win!\n");
won = won+1;
cash = cash+bet;
printf("\nYou have %d Wins and %d Losses. Awesome!\n", won, loss);
dealer_total=0;
askover();
}
if(p>21) //If player total is over 21, loss
{
printf("\nWoah Buddy, You Went WAY over.\n");
loss = loss+1;
cash = cash - bet;
printf("\nYou have %d Wins and %d Losses. Awesome!\n", won, loss);
dealer_total=0;
askover();
}
if(p<=21) //If player total is less than 21, ask to hit or stay
{
printf("\n\nWould You Like to Hit or Stay?");
scanf("%c", &choice3);
while((choice3!='H') && (choice3!='h') && (choice3!='S') && (choice3!='s')) // If invalid choice entered
{
printf("\n");
printf("Please Enter H to Hit or S to Stay.\n");
scanf("%c",&choice3);
}
if((choice3=='H') || (choice3=='h')) // If Hit, continues
{
randcard();
player_total = p + l;
p = player_total;
printf("\nYour Total is %d\n", p);
dealer();
if(dealer_total==21) //Is dealer total is 21, loss
{
printf("\nDealer Has the Better Hand. You Lose.\n");
loss = loss+1;
cash = cash - bet;
printf("\nYou have %d Wins and %d Losses. Awesome!\n", won, loss);
dealer_total=0;
askover();
}
if(dealer_total>21) //If dealer total is over 21, win
{
printf("\nDealer Has Went Over!. You Win!\n");
won = won+1;
cash = cash+bet;
printf("\nYou have %d Wins and %d Losses. Awesome!\n", won, loss);
dealer_total=0;
askover();
}
}
if((choice3=='S') || (choice3=='s')) // If Stay, does not continue
{
printf("\nYou Have Chosen to Stay at %d. Wise Decision!\n", player_total);
stay();
}
}
i++; //While player total and dealer total are less than 21, re-do while loop
} // End While Loop
} // End Function
void play() //Plays game
{ int p=0; // holds value of player_total
int i=1; // counter for asking user to hold or stay (aka game turns)
char choice3;
cash = cash;
cash_test();
printf("\nCash: $%d\n",cash); //Prints amount of cash user has
randcard(); //Generates random card
player_total = p + l; //Computes player total
p = player_total;
printf("\nYour Total is %d\n", p); //Prints player total
dealer(); //Computes and prints dealer total
betting(); //Prompts user to enter bet amount
while(i<=21) //While loop used to keep asking user to hit or stay at most twenty-one times
// because there is a chance user can generate twenty-one consecutive 1's
{
if(p==21) //If user total is 21, win
{
printf("\nUnbelievable! You Win!\n");
won = won+1;
cash = cash+bet;
printf("\nYou have %d Wins and %d Losses. Awesome!\n", won, loss);
dealer_total=0;
askover();
}
if(p>21) //If player total is over 21, loss
{
printf("\nWoah Buddy, You Went WAY over.\n");
loss = loss+1;
cash = cash - bet;
printf("\nYou have %d Wins and %d Losses. Awesome!\n", won, loss);
dealer_total=0;
askover();
}
[招生]科锐逆向工程师培训(2024年11月15日实地，远程教学同时开班, 第51期)
|
|
|---|---|
