Linux环境rarcrack源码原理（重在学习）

// Standard headers
#include 
#include 
#include 
#include 
#include 

// libxml2 headers
#include 
#include 
#include 
#include 
#include 

// Default char list
char default_ABC[] = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";

// Command checks the type of file
const char CMD_DETECT[] = "file -i -b %s";

// File extensions
// "" is the end of the list
const char *TYPE[] = { "rar", "7z", "zip", "" };

// File Types
const char *MIME[] = { "application/x-rar;", "application/x-7z-compressed;", "application/zip;", "" };

// Commnds for each file type
const char *CMD[] = { "unrar t -y -p%s %s 2>&1", "7z t -y -p%s %s 2>&1", "unzip -P%s -t %s 2>&1", "" };

// Max password length
#define PWD_LEN 100

char *getfirstpassword();
void crack_start(unsigned int threads);

char* ABC = (char*) &default_ABC;
int ABCLEN;

char password[PWD_LEN+1] = {'',''}; //this contains the actual password
char password_good[PWD_LEN+1] = {'', ''};  //this changed only once, when we found the good passord
unsigned int curr_len = 1; //current password length
long counter = 0;	//this couning probed passwords
xmlMutexPtr pwdMutex;	//mutex for password char array
char filename[255];	//the archive file name
char statname[259];	//status xml file name filename + ".xml"
xmlDocPtr status;
int finished = 0;
xmlMutexPtr finishedMutex;
char finalcmd[300] = {'', ''}; //this depending on arhive file type, it's a command to test file with password

char *getfirstpassword() {
    static char ret[2];
    ret[0] = ABC[0];
    ret[1] = '';
    return (char*) &ret;
}

void savestatus() {
    xmlNodePtr root = NULL;
    xmlNodePtr node = NULL;
    xmlChar* tmp = NULL;
    if ((strlen(statname) > 0) && status) {
        root = xmlDocGetRootElement(status);
        if (root) {
            xmlMutexLock(finishedMutex);
            for (node = root->children; node; node = node->next) {
                if (xmlStrcmp(node->name, (const xmlChar*)"current") == 0) {
                    xmlMutexLock(pwdMutex);
                    tmp = xmlEncodeEntitiesReentrant(status, (const xmlChar*) &password);
                    xmlMutexUnlock(pwdMutex);

                    if (node->children) {
                        if (password[0] == '') {
                            xmlNodeSetContent(node->children, (const xmlChar*)getfirstpassword());
                        } else {
                            xmlNodeSetContent(node->children, tmp);
                        }
                    }

                    xmlFree(tmp);
                } else if ((finished == 1) && (xmlStrcmp(node->name, (const xmlChar*)"good_password") == 0)) {
                    tmp =  xmlEncodeEntitiesReentrant(status, (const xmlChar*) &password_good);

                    if (node->children) {
                        xmlNodeSetContent(node->children, tmp);
                    }

                    xmlFree(tmp);
                }
            }
            xmlMutexUnlock(finishedMutex);
        }
        xmlSaveFormatFileEnc(statname, status, "UTF-8", 1);
    }
}

int abcnumb(char a) {
    int i = 0;
    for (i = 0; i < ABCLEN; i++) {
        if (ABC[i] == a) {
            return i;
        }
    }

    return 0;
}

int loadstatus() {
    xmlNodePtr root = NULL;
    xmlNodePtr node = NULL;
    xmlParserCtxtPtr parserctxt;
    int ret = 0;
    char* tmp;
    FILE* totest;
    totest = fopen(statname, "r");
    if (totest) {
        fclose(totest);
        status = xmlParseFile(statname);
    }

    if (status) {
        root = xmlDocGetRootElement(status);
    } else {
        status = xmlNewDoc(NULL);
    }

    if (root) {
        parserctxt = xmlNewParserCtxt();
        for (node = root->children; node; node = node->next) {
            if (xmlStrcmp(node->name, (const xmlChar*)"abc") == 0) {
                if (node->children && (strlen((const char*)node->children->content) > 0)) {
                    ABC = (char *)xmlStringDecodeEntities(parserctxt, (const xmlChar*)node->children->content, XML_SUBSTITUTE_BOTH, 0, 0, 0);
                } else {
                    ret = 1;
                }
            } else if (xmlStrcmp(node->name, (const xmlChar*)"current") == 0) {
                if (node->children && (strlen((const char*)node->children->content) > 0)) {
                    tmp = (char *)xmlStringDecodeEntities(parserctxt, (const xmlChar*)node->children->content, XML_SUBSTITUTE_BOTH, 0, 0, 0);
                    strcpy(password,tmp);
                    curr_len = strlen(password);
                    printf("INFO: Resuming cracking from password: '%s'n",password);
                    xmlFree(tmp);
                } else {
                    ret = 1;
                }
            } else if (xmlStrcmp(node->name, (const xmlChar*)"good_password") == 0) {
                if (node->children && (strlen((const char*)node->children->content) > 0)) {
                    tmp = (char *)xmlStringDecodeEntities(parserctxt, node->children->content, XML_SUBSTITUTE_BOTH,0,0,0);
                    strcpy(password,tmp);
                    curr_len = strlen(password);
                    xmlMutexLock(finishedMutex);
                    finished = 1;
                    xmlMutexUnlock(finishedMutex);
                    strcpy((char*) &password_good, (char*) &password);
                    printf("GOOD: This archive was succesfully crackedn");
                    printf("      The good password is: '%s'n", password);
                    xmlFree(tmp);
                    ret = 1;
                }
            }
        }

        xmlFreeParserCtxt(parserctxt);
    } else {
        root = xmlNewNode(NULL, (const xmlChar*)"rarcrack");
        xmlDocSetRootElement(status, root);
        node = xmlNewTextChild(root, NULL, (const xmlChar*)"abc", (const xmlChar*)ABC);
        node = xmlNewTextChild(root, NULL, (const xmlChar*)"current", (const xmlChar*)getfirstpassword());
        node = xmlNewTextChild(root, NULL, (const xmlChar*)"good_password", (const xmlChar*)"");
        savestatus();
    }

    return ret;
}

void nextpass2(char *p, unsigned int n) {
    int i;
    if (p[n] == ABC[ABCLEN-1]) {
        p[n] = ABC[0];

        if (n > 0) {
            nextpass2(p, n-1);
        } else {
            for (i=curr_len; i>=0; i--) {
                p[i+1]=p[i];
            }

            p[0]=ABC[0];
            p[++curr_len]='';
        }
    } else {
        p[n] = ABC[abcnumb(p[n])+1];
    }
}

char *nextpass() {
    //importANT: the returned string must be freed
    char *ok = malloc(sizeof(char)*(PWD_LEN+1));
    xmlMutexLock(pwdMutex);
    strcpy(ok, password);
    nextpass2((char*) &password, curr_len - 1);
    xmlMutexUnlock(pwdMutex);
    return ok;
}

void *status_thread() {
    int pwds;
    const short status_sleep = 3;
    while(1) {
        sleep(status_sleep);
        xmlMutexLock(finishedMutex);
        pwds = counter / status_sleep;
        counter = 0;

        if (finished != 0) {
            break;
        }

        xmlMutexUnlock(finishedMutex);
        xmlMutexLock(pwdMutex);
        printf("Probing: '%s' [%d pwds/sec]n", password, pwds);
        xmlMutexUnlock(pwdMutex);
        savestatus();	//FIXME: this is wrong, when probing current password(s) is(are) not finished yet, and the program is exiting
    }
}

void *crack_thread() {
    char *current;
    char ret[200];
    char cmd[400];
    FILE *Pipe;
    while (1) {
        current = nextpass();
        sprintf((char*)&cmd, finalcmd, current, filename);
        Pipe = popen(cmd, "r");
        while (! feof(Pipe)) {
            fgets((char*)&ret, 200, Pipe);
            if (strcasestr(ret, "ok") != NULL) {
                strcpy(password_good, current);
                xmlMutexLock(finishedMutex);
                finished = 1;
                printf("GOOD: password cracked: '%s'n", current);
                xmlMutexUnlock(finishedMutex);
                savestatus();
                break;
            }
        }

        pclose(Pipe);
        xmlMutexLock(finishedMutex);
        counter++;

        if (finished != 0) {
            xmlMutexUnlock(finishedMutex);
            break;
        }

        xmlMutexUnlock(finishedMutex);
        free(current);
    }
}

void crack_start(unsigned int threads) {
    pthread_t th[13];
    unsigned int i;

    for (i = 0; i < threads; i++) {
        (void) pthread_create(&th[i], NULL, crack_thread, NULL);
    }

    (void) pthread_create(&th[12], NULL, status_thread, NULL);

    for (i = 0; i < threads; i++) {
        (void) pthread_join(th[i], NULL);
    }

    (void) pthread_join(th[12], NULL);
}

void init(int argc, char **argv) {
    int i, j;
    int help = 0;
    int threads = 1;
    int archive_type = -1;
    FILE* totest;
    char test[300];
    xmlInitThreads();
    pwdMutex = xmlNewMutex();
    finishedMutex = xmlNewMutex();
    if (argc == 1) {
        printf("USAGE: rarcrack encrypted_archive.ext [--threads NUM] [--type rar|zip|7z]n");
        printf("       For more information please run "rarcrack --help"n");
        help = 1;
    } else {
        for (i = 1; i < argc; i++) {
            if (strcmp(argv[i],"--help") == 0) {
                printf("Usage:   rarcrack encrypted_archive.ext [--threads NUM] [--type rar|zip|7z]nn");
                printf("Options: --help: show this screen.n");
                printf("         --type: you can specify the archive program, this needed whenn");
                printf("                 the program couldn't detect the proper file typen");
                printf("         --threads: you can specify how many threadsn");
                printf("                    will be run, maximum 12 (default: 2)nn");
                printf("Info:    This program supports only RAR, ZIP and 7Z encrypted archives.n");
                printf("         RarCrack! usually detects the archive type.nn");
                help = 1;
                break;
            } else if (strcmp(argv[i],"--threads") == 0) {
                if ((i + 1) < argc) {
                    sscanf(argv[++i], "%d", &threads);
                    if (threads < 1) threads = 1;
                    if (threads > 12) {
                        printf("INFO: number of threads adjusted to 12n");
                        threads = 12;
                    }
                } else {
                    printf("ERROR: missing parameter for option: --threads!n");
                    help = 1;
                }
            } else if (strcmp(argv[i],"--type") == 0) {
                if ((i + 1) < argc) {
                    sscanf(argv[++i], "%s", test);
                    for (j = 0; strcmp(TYPE[j], "") != 0; j++) {
                        if (strcmp(TYPE[j], test) == 0) {
                            strcpy(finalcmd, CMD[j]);
                            archive_type = j;
                            break;
                        }
                    }

                    if (archive_type < 0) {
                        printf("WARNING: invalid parameter --type %s!n", argv[i]);
                        finalcmd[0] = '';
                    }
                } else {
                    printf("ERROR: missing parameter for option: --type!n");
                    help = 1;
                }
            } else {
                strcpy((char*)&filename, argv[i]);
            }
        }
    }

    if (help == 1) {
        return;
    }

    sprintf((char*)&statname,"%s.xml",(char*)&filename);
    totest = fopen(filename,"r");
    if (totest == NULL) {
        printf("ERROR: The specified file (%s) is not exists or n", filename);
        printf("       you don't have a right permissions!n");
        return;
    } else {
        fclose(totest);
    }

    if (finalcmd[0] == '') {
        //when we specify the file type, the programm will skip the test
        sprintf((char*)&test, CMD_DETECT, filename);
        totest = popen(test,"r");
        fscanf(totest,"%s",(char*)&test);
        pclose(totest);

        for (i = 0; strcmp(MIME[i],"") != 0; i++) {
            if (strcmp(MIME[i],test) == 0) {
                strcpy(finalcmd,CMD[i]);
                archive_type = i;
                break;
            }
        }

        if (archive_type > -1 && archive_type < 3) {
            printf("INFO: detected file type: %sn", TYPE[archive_type]);
        }
    } else {
        if (archive_type > -1 && archive_type < 3) {
            printf("INFO: the specified archive type: %sn", TYPE[archive_type]);
        }
    }

    if (finalcmd[0] == '') {
        printf("ERROR: Couldn't detect archive typen");
        return;
    }

    printf("INFO: cracking %s, status file: %sn", filename, statname);

    if (loadstatus() == 1) {
        printf("ERROR: The status file (%s) is corrupted!n", statname);
        return;
    }

    ABCLEN = strlen(ABC);

    if (password[0] == '') {
        password[0] = ABC[0];
    }

    crack_start(threads);
}

int main(int argc, char **argv) {
    // Print author
    printf("RarCrack! 0.2 by David Zoltan Kedves (kedazo@gmail.com)nn");

    init(argc,argv);

    if (ABC != (char*) &default_ABC) {
        xmlFree(ABC);
    }

    if (status) {
        xmlFreeDoc(status);
    }

    // Free memory
    xmlFreeMutex(pwdMutex);
    xmlFreeMutex(finishedMutex);

    // 0
    return EXIT_SUCCESS;
}

附使用方法：编译安装或执行apt-get install rarcrack下载安装后，执行如下命令

rarcrack 文件名 --threads 线程数 --type rar|zip|7z

记住，参数单词不要写错，比如threads不能写成thread，“--”不能写成‘-’，不然会出现类似如下错误

ERROR: The specified file (rar) is not exists or 
       you don't have a right permissions!