目前正在尝试使用 pthread_create
、pthread_join
、pthread_exit
和 pthread_self
让此程序使用多线程。然后我打算在我的代码中使用 crypt_r
代替 crypt
。
最多只能有 8 个线程,但我什至不知道如何开始使用两个线程。我只有一行声明 pthread_t t1,t2,t3,t4,t5,t6,t7,t8
。
这些的计划是将它们放入 pthread_create
但除了初始化这些值之外,我不知道从这里去哪里。
我知道 pthread_create 的输入类似于 pthread_create(t1, NULL, ... , ...)
但我不知道如何进行第三个输入或第四个输入是什么输入甚至是。
然后我必须确保根据命令行 arg 指定的线程数拆分每个线程正在检查的字母范围。到目前为止,我将其设计为仅在一个线程上工作,并计划将其移动到具有多线程的 crypt_r
...
我真的很困惑如何才能完成这项工作。如果可能的话。
我知道某种 void 函数是 pthread_create
的第三个入口.. 但该函数必须是我的 passwordChecker 吗?或者什么?
/*
crack.exe
*/
/* g++ -o crack crack.c -lcrypt -lpthread */
//#define _GNU_SOURCE
#include <crypt.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <pthread.h>
#include <string.h>
#include <math.h>
void *passwordLooper(int ks, char target[9], char s[10]);
void *threadFunction(void *threads);
int main(int argc, char *argv[]){ /* usage = crack threads keysize target */
int i = 0;
/* arg[0] = crack, arg[1] = #of threads arg[2] = size of password, arg[3] = hashed password being cracked */
if (argc != 4) {
fprintf(stderr, "Too few/many arguements give.\n");
fprintf(stderr, "Proper usage: ./crack threads keysize target\n");
exit(0);
}
int threads = *argv[1]-'0'; // threads is now equal to the second command line argument number
int keysize = *argv[2]-'0'; // keysize is now equal to the third command line argument number
char target[9];
strcpy(target, argv[3]);
char salt[10];
while ( i < 2 ){ //Takes first two characters of the hashed password and assigns them to the salt variable
salt[i] = target[i];
i++;
}
printf("threads = %d\n", threads); /*used for testing */
printf("keysize = %d\n", keysize);
printf("target = %s\n", target);
printf("salt = %s\n", salt);
if (threads < 1 || threads > 8){
fprintf(stderr, "0 < threads <= 8\n");
exit(0);
} /*Checks to be sure that threads and keysize are*/
if (keysize < 1 || keysize > 8){ /*of the correct size */
fprintf(stderr, "0 < keysize <= 8\n");
exit(0);
}
pthread_t t1,t2,t3,t4,t5,t6,t7,t8;
if ( threads = 1 ){
pthread_create(&t1, NULL, *threadFunction, threads);
}
char unSalted[30];
int j = 0;
for (i = 2; target[i] != '\0'; i++){ /*generates variable from target that does not include salt*/
unSalted[j] = target[i];
j++;
}
printf("unSalted = %s\n", unSalted); //unSalted is the variable target without the first two characters (the salt)
char password[9] = {0};
passwordLooper(keysize, target, salt);
}
/*_____________________________________________________________________________________________________________*/
/*_____________________________________________________________________________________________________________*/
void *passwordLooper(int ks, char target[9], char s[10]){
char password[9] = {0};
struct crypt_data cd;
cd.initialized = 0;
int result;
for (;;){
int level = 0;
while (level < ks && strcmp( crypt(password, s), target ) != 0) {
if (password[level] == 0){
password[level] = 'a';
break;
}
if (password[level] >= 'a' && password[level] < 'z'){
password[level]++;
break;
}
if (password[level] == 'z'){
password[level] = 'a';
level++;
}
}
char *cryptPW = crypt(password, s);
result = strcmp(cryptPW, target);
if (result == 0){ //if result is zero, cryptPW and target are the same
printf("result = %d\n", result);
printf ("Password found: %s\n", password);
printf("Hashed version of password is %s\n", cryptPW);
break;
}
if (level >= ks){ //if level ends up bigger than the keysize, break, no longer checking for passwords
printf("Password not found\n");
break;
}
}
return 0;
}
使用 malloc 结构
/*
crack.exe
By: Zach Corse
*/
/* g++ -o crack crack.c -lcrypt -lpthread */
//#define _GNU_SOURCE
#include <crypt.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <pthread.h>
#include <string.h>
#include <math.h>
#include <malloc.h>
void *passwordLooper(void *passwordData);
//void *threadFunction(void *threads);
typedef struct{
int keysize;
char *target;
char *salt;
}passwordData;
int main(int argc, char *argv[]){ /* usage = crack threads keysize target */
int i = 0;
/* arg[0] = crack, arg[1] = #of threads arg[2] = size of password, arg[3] = hashed password being cracked */
if (argc != 4) {
fprintf(stderr, "Too few/many arguements give.\n");
fprintf(stderr, "Proper usage: ./crack threads keysize target\n");
exit(0);
}
int threads = *argv[1]-'0'; // threads is now equal to the second command line argument number
int keysize = *argv[2]-'0'; // keysize is now equal to the third command line argument number
char target[9];
strcpy(target, argv[3]);
char salt[10];
while ( i < 2 ){ //Takes first two characters of the hashed password and assigns them to the salt variable
salt[i] = target[i];
i++;
}
printf("threads = %d\n", threads); /*used for testing */
printf("keysize = %d\n", keysize);
printf("target = %s\n", target);
printf("salt = %s\n", salt);
if (threads < 1 || threads > 8){
fprintf(stderr, "0 < threads <= 8\n");
exit(0);
} /*Checks to be sure that threads and keysize are*/
if (keysize < 1 || keysize > 8){ /*of the correct size */
fprintf(stderr, "0 < keysize <= 8\n");
exit(0);
}
pthread_t t1,t2,t3,t4,t5,t6,t7,t8;
struct crypt_data data;
data.initialized = 0;
//~ passwordData.keysize = keysize;
//~ passwordData.target = target;
//~ passwordData.salt = salt;
passwordData *pwd = (passwordData *) malloc(sizeof(pwd));
pwd->keysize = keysize;
pwd->target = target;
pwd->salt = salt;
//~ if ( threads = 1 ){
//~ pthread_create(&t1, NULL, *threadFunction, threads);
//~ }
char unSalted[30];
int j = 0;
for (i = 2; target[i] != '\0'; i++){ /*generates variable from target that does not include salt*/
unSalted[j] = target[i];
j++;
}
printf("unSalted = %s\n", unSalted); //unSalted is the variable target without the first two characters (the salt)
char password[9] = {0};
passwordLooper(pwd);
}
/*_____________________________________________________________________________________________________________*/
/*_____________________________________________________________________________________________________________*/
void *passwordLooper(passwordData pwd){
char password[9] = {0};
int result;
int ks = pwd.keysize;
char *target = pwd.target;
char *s = pwd.salt;
for (;;){
int level = 0;
while (level < ks && strcmp( crypt(password, s), target ) != 0) {
if (password[level] == 0){
password[level] = 'a';
break;
}
if (password[level] >= 'a' && password[level] < 'z'){
password[level]++;
break;
}
if (password[level] == 'z'){
password[level] = 'a';
level++;
}
}
char *cryptPW = crypt(password, s);
result = strcmp(cryptPW, target);
if (result == 0){ //if result is zero, cryptPW and target are the same
printf("result = %d\n", result);
printf ("Password found: %s\n", password);
printf("Hashed version of password is %s\n", cryptPW);
break;
}
if (level >= ks){ //if level ends up bigger than the keysize, break, no longer checking for passwords
printf("Password not found\n");
break;
}
}
return 0;
}
最佳答案
好吧,这是 pthread_create 的原型(prototype):
整数 pthread_create(pthread_t *restrict thread, const pthread_attr_t *restrict attr, void *(*start_routine)(void *), void *restrict arg);
它表明第三个参数是一个指向函数的指针,该函数返回一个指向 void 的指针,并将一个指向 void 的指针作为其唯一参数。我看到你有一个原型(prototype):
void *threadFunction(void *threads);
哪个符合那些规范,但实际上并没有写出来? pthread_create 中的第 4 个参数只是一个指向 void 的指针,它基本上可以包含您想要的任何内容。
我猜你想要线程化的函数实际上是 passwordLooper,它有 3 个参数。但是 pthread_create 指定了一个只需要 1 个参数的函数。你必须找到一个解决方法,这样你就只能接受一个参数你的 passwordLooper 函数仍然传递你关心的所有 3 个变量。有几种方法可以做到这一点:
- 全局变量(糟糕,不是线程安全的,不要真的这样做)
- malloc() 一些内存,memcpy() 你的参数到其中(或指向它们的指针),然后将新 malloc() 的内存传递给 pthread_create()。在你调用的函数中,你必须将 3 个变量从 void * 中解析出来(hacky,但理论上可行)
- 定义一个包含您的 3 个参数的结构,分配该结构的副本,将您的变量复制到新分配的结构中,并将其作为您的第 4 个参数传递。这极大地简化了返回值的解析,并且是完成将多个变量作为 pthread_create 的第四个参数传递的一般方法
关于c - 在 C 中多线程密码检查器,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/19073436/