connectionhandler.cpp

一个UNIX/LINUX下的基于内容的过滤服务器源代码

// if we don't do this the browsers complain
std::string ConnectionHandler::miniURLEncode(std::string s) {
    std::string encoded;
    char* buf = new char[16];  // way longer than needed
    unsigned char c;
    for(int i=0; i < (signed)s.length(); i++) {
        c = s[i];
        if ((c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') || (c >= '0' && c <= '9')) {  // allowed characters in a url that have non special meaning
            encoded += c;
            continue;
        }
        sprintf(buf, "%x", c);
        encoded += "%";
        encoded += buf;
    }
    delete[] buf;
    return encoded;
}

void ConnectionHandler::doTheLogMan(std::string who, std::string from, std::string where, std::string what, std::string how, int size, struct timeval *thestart, bool cachehit, int code, std::string mimetype) {
    std::string logline,year,month,day,hour,min,sec,when,ssize,duration, utime, hitmiss, hier;
    struct timeval theend;
    struct timezone notused;
    gettimeofday(&theend, &notused);
    long durationsecs, durationusecs;
    durationsecs = theend.tv_sec - (*thestart).tv_sec;
    durationusecs = theend.tv_usec - (*thestart).tv_usec;
    durationusecs = (durationusecs / 1000) + durationsecs * 1000;
    String temp = String((int)durationusecs);
    while (temp.length() < 6) {
        temp = " " + temp;
    }
    duration = temp.toCharArray();
    temp = String((int)(theend.tv_usec / 1000));
    while (temp.length() < 3) {
        temp = "0" + temp;
    }
    if (temp.length() > 3) {
        temp = "999";
    }
    utime = temp.toCharArray();
    utime = "." + utime;
    utime = String((int)theend.tv_sec).toCharArray() + utime;

    if (what.length() > 3000) {
        what = what.substr(0, 2999);
    }

    if (code == 403) {
        hitmiss = "TCP_DENIED/403";
    }
    else {
        if (cachehit) {
            hitmiss = "TCP_HIT/";
            hitmiss += String((int)code).toCharArray();
        }
        else {
           hitmiss = "TCP_MISS/";
           hitmiss += String((int)code).toCharArray();
        }
    }
    hier = "DEFAULT_PARENT/";
    hier += o.proxy_ip;

    time_t tnow;  // to hold the result from time()
    struct tm *tmnow;  // to hold the result from localtime()
    time(&tnow);  // get the time after the lock so all entries in order
    tmnow = localtime(&tnow);  // convert to local time (BST, etc)
    year = String(tmnow->tm_year + 1900).toCharArray();
    month = String(tmnow->tm_mon + 1).toCharArray();
    day = String(tmnow->tm_mday).toCharArray();
    hour = String(tmnow->tm_hour).toCharArray();
    temp = String(tmnow->tm_min);
    if (temp.length() == 1) { temp = "0" + temp;}
    min = temp.toCharArray();
    temp = String(tmnow->tm_sec);
    if (temp.length() == 1) { temp = "0" + temp;}
    sec = temp.toCharArray();
    ssize = String(size).toCharArray();
    when = year + "." + month + "." + day + " " + hour + ":" + min + ":" + sec;
    switch(o.log_file_format){
        case 4:
            logline = when +"\t"+ who + "\t" + from + "\t" + where + "\t" + what + "\t" + how + "\t" + ssize + "\n";
            break;
        case 3:
            logline = utime + " " + duration + " " + from + " " + hitmiss + " " + ssize + " " + how + " " + where + " " + who + " " + hier + " " + mimetype + "\n";
            break;

        case 2:
            logline = "\"" + when +"\",\""+ who + "\",\"" + from + "\",\"" + where + "\",\"" + what + "\",\"" + how + "\",\"" + ssize + "\"\n";
            break;
        default:
            logline = when +" "+ who + " " + from + " " + where + " " + what + " " + how + " " + ssize + "\n";
    }
    UDSocket ipcsock;
    if (ipcsock.getFD() < 0) {
        syslog(LOG_ERR, "%s","Error creating ipc socket to log");
        return;
    }
    if (ipcsock.connect((char*) o.ipc_filename.c_str()) < 0) {  // connect to dedicated logging proc
        syslog(LOG_ERR, "%s","Error connecting via ipc to log");
        ipcsock.close();
        return;
    }
    ipcsock.writeString(logline.c_str());
    ipcsock.close();
}



void ConnectionHandler::decideHowToLog(std::string who, std::string from, std::string where, unsigned int port, std::string what, std::string how, int size, int loglevel, bool isnaughty, bool isexception, int logexceptions, bool istext, struct timeval *thestart, bool cachehit, int code, std::string mimetype) {

    if (loglevel == 0) {
        return;
    }
    if (port != 0 && port != 80) {
        String newwhere = where.c_str();
        if (newwhere.after("://").contains("/")) {
            String proto, host, path;
            proto = newwhere.before("://");
            host = newwhere.after("://");
            path = host.after("/");
            host = host.before("/");
            newwhere = proto;
            newwhere += "://";
            newwhere += host;
            newwhere += ":";
            newwhere += String((int)port);
            newwhere += "/";
            newwhere += path;
            where = newwhere.toCharArray();
        }
        else {
            where += ":";
            where += String((int)port).toCharArray();
        }
    }
    if (isnaughty) {
        what = "*DENIED* " + what;
        // make it stand out in the logs and also
        // more easily findable with a search
    }
    if (isexception) {
       if (logexceptions == 1) {
            what = "*EXCEPTION* " + what;
        }
        else {
            what = "";
        }
    }
    if ((isexception && logexceptions == 1)
         || isnaughty
         || loglevel == 3
         || (loglevel == 2 && istext)) {
        doTheLogMan(who, from, where, what, how, size, thestart, cachehit, code, mimetype);
    }
}



bool ConnectionHandler::wasClean(String url) {
    url = url.after("://");
    UDSocket ipcsock;
    if (ipcsock.getFD() < 0) {
        syslog(LOG_ERR, "%s","Error creating ipc socket to url cache");
        return false;
    }
    if (ipcsock.connect((char*) o.urlipc_filename.c_str()) < 0) {  // conn to dedicated url cach proc
        syslog(LOG_ERR, "%s","Error connecting via ipc to url cache");
        ipcsock.close();
        return false;
    }
    url += "\n";
    char* reply = new char[8];
    #ifdef DGDEBUG
        std::cout << "sending clean request:" << url.toCharArray() << std::endl;
    #endif
    try {
        ipcsock.writeString(url.toCharArray());  // throws on err
    }
    catch (exception& e) {
        #ifdef DGDEBUG
            std::cerr << "Exception writing to url cache" << std::endl;
            std::cerr << e.what() << std::endl;
        #endif
        syslog(LOG_ERR, "%s","Exception writing to url cache");
        syslog(LOG_ERR, "%s", e.what());
    }
    try {
        ipcsock.getline(reply, 7, 6);  // throws on err
    }
    catch (exception& e) {
        #ifdef DGDEBUG
            std::cerr << "Exception reading from url cache" << std::endl;
            std::cerr << e.what() << std::endl;
        #endif
        syslog(LOG_ERR, "%s","Exception reading from url cache");
        syslog(LOG_ERR, "%s", e.what());
    }
    ipcsock.close();
    if (reply[0] == 'Y') {
        delete[] reply;
        return true;
    }
    delete[] reply;
    return false;
}


void ConnectionHandler::addToClean(String url) {
    url = url.after("://");
    UDSocket ipcsock;
    if (ipcsock.getFD() < 0) {
        syslog(LOG_ERR, "%s","Error creating ipc socket to url cache");
        return;
    }
    if (ipcsock.connect((char*) o.urlipc_filename.c_str()) < 0) {  // conn to dedicated url cach proc
        syslog(LOG_ERR, "%s","Error connecting via ipc to url cache");
        #ifdef DGDEBUG
            std::cout << "Error connecting via ipc to url cache" << std::endl;
        #endif
        return;
    }
    url += "\n";
    url = "A " + url;
    try {
        ipcsock.writeString(url.toCharArray());  // throws on err
    }
    catch (exception& e) {
        #ifdef DGDEBUG
            std::cerr << "Exception adding to url cache" << std::endl;
            std::cerr << e.what() << std::endl;
        #endif
        syslog(LOG_ERR, "%s","Exception adding to url cache");
        syslog(LOG_ERR, "%s", e.what());
    }
    ipcsock.close();
}

void ConnectionHandler::requestChecks(HTTPHeader *header, NaughtyFilter *checkme, String *urld, std::string *clientip, std::string *clientuser, int filtergroup, bool *ispostblock) {
    char *i;
    int j;
    String temp;
    temp = (*urld);
    bool igsl = (*o.fg[filtergroup]).inGreySiteList(temp);
    bool igul = (*o.fg[filtergroup]).inGreyURLList(temp);

    if ((*o.fg[filtergroup]).blanketblock == 1 && !igsl && !igul) {
        (*checkme).isItNaughty = true;
        (*checkme).whatIsNaughty = o.language_list.getTranslation(502);
        // Blanket Block is active and that site is not on the white list.
        (*checkme).whatIsNaughtyLog = (*checkme).whatIsNaughty;
    }
    else if (o.inBannedIPList(clientip)) {
        (*checkme).isItNaughty = true;
        (*checkme).whatIsNaughtyLog = o.language_list.getTranslation(100);
                // Your IP address is not allowed to web browse:
        (*checkme).whatIsNaughtyLog += (*clientip);
        (*checkme).whatIsNaughty = o.language_list.getTranslation(101);
                // Your IP address is not allowed to web browse.
    }
    else if (o.inBannedUserList(clientuser)) {
        (*checkme).isItNaughty = true;
        (*checkme).whatIsNaughtyLog = o.language_list.getTranslation(102);
                // Your username is not allowed to web browse:
        (*checkme).whatIsNaughtyLog += (*clientuser);
        (*checkme).whatIsNaughty = (*checkme).whatIsNaughtyLog;
    }


    if (!(*checkme).isItNaughty && (*o.fg[filtergroup]).blanketblock == 0) {
        if ((*o.fg[filtergroup]).blanket_ip_block == 1 && isIPHostnameStrip(temp)) {
            (*checkme).isItNaughty = true;
            (*checkme).whatIsNaughty = o.language_list.getTranslation(502);
            //Blanket IP Block is active and that address is an IP only address.
            (*checkme).whatIsNaughtyLog = (*checkme).whatIsNaughty;
        }
        else {
            if (!igsl && !igul && ((i = (*o.fg[filtergroup]).inBannedSiteList(temp)) != NULL)) {
                (*checkme).whatIsNaughty = o.language_list.getTranslation(500); // banned site
                (*checkme).whatIsNaughty += i;
                (*checkme).whatIsNaughtyLog = (*checkme).whatIsNaughty;
                (*checkme).isItNaughty = true;
            }
        }
    }
    if (!(*checkme).isItNaughty) {
        if (!igsl && !igul && ((i = (*o.fg[filtergroup]).inBannedURLList(temp)) != NULL)) {
            (*checkme).whatIsNaughty = o.language_list.getTranslation(501);
            // Banned URL:
            (*checkme).whatIsNaughty += i;
            (*checkme).whatIsNaughtyLog = (*checkme).whatIsNaughty;
            (*checkme).isItNaughty = true;
        }
        else if (!igsl && !igul && ((j = (*o.fg[filtergroup]).inBannedRegExpURLList(temp)) >= 0)) {
            (*checkme).isItNaughty = true;
            (*checkme).whatIsNaughtyLog = o.language_list.getTranslation(503);
            // Banned Regular Expression URL:
            (*checkme).whatIsNaughtyLog += (*o.fg[filtergroup]).banned_regexpurl_list_source[j].toCharArray();
            (*checkme).whatIsNaughty = o.language_list.getTranslation(504);
            // Banned Regular Expression URL found.