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/* +------------------------------------+
* | Inspire Internet Relay Chat Daemon |
* +------------------------------------+
*
* InspIRCd: (C) 2002-2007 InspIRCd Development Team
* See: http://www.inspircd.org/wiki/index.php/Credits
*
* This program is free but copyrighted software; see
* the file COPYING for details.
*
* ---------------------------------------------------
*/
#include "inspircd.h"
#include "xline.h"
#include "dns.h"
#include "users.h"
#include "channels.h"
#include "modules.h"
#ifndef WINDOWS
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#endif
/* $ModDesc: Provides handling of DNS blacklists */
/* Class holding data for a single entry */
class DNSBLConfEntry
{
public:
enum EnumBanaction { I_UNKNOWN, I_KILL, I_ZLINE, I_KLINE, I_GLINE };
std::string name, domain, reason;
EnumBanaction banaction;
long duration;
int bitmask;
unsigned long stats_hits, stats_misses;
DNSBLConfEntry(): duration(86400),bitmask(0),stats_hits(0), stats_misses(0) {}
~DNSBLConfEntry() { }
};
/** Resolver for CGI:IRC hostnames encoded in ident/GECOS
*/
class DNSBLResolver : public Resolver
{
int theirfd;
userrec* them;
DNSBLConfEntry *ConfEntry;
public:
DNSBLResolver(Module *me, InspIRCd *ServerInstance, const std::string &hostname, userrec* u, int userfd, DNSBLConfEntry *conf, bool &cached)
: Resolver(ServerInstance, hostname, DNS_QUERY_A, cached, me)
{
theirfd = userfd;
them = u;
ConfEntry = conf;
}
virtual void OnLookupComplete(const std::string &result, unsigned int ttl, bool cached)
{
/* Check the user still exists */
if ((them) && (them == ServerInstance->SE->GetRef(theirfd)))
{
// Now we calculate the bitmask: 256*(256*(256*a+b)+c)+d
if(result.length())
{
unsigned int bitmask = 0;
bool show = false;
in_addr resultip;
/* Convert the result to an in_addr (we can gaurantee we got ipv4)
* Whoever did the loop that was here before, I AM CONFISCATING
* YOUR CRACKPIPE. you know who you are. -- Brain
*/
inet_aton(result.c_str(), &resultip);
bitmask = resultip.s_addr >> 24; /* Last octet (network byte order */
bitmask &= ConfEntry->bitmask;
if (bitmask != 0)
{
std::string reason = ConfEntry->reason;
std::string::size_type x = reason.find("%ip%");
while (x != std::string::npos)
{
reason.erase(x, 4);
reason.insert(x, them->GetIPString());
x = reason.find("%ip%");
}
ConfEntry->stats_hits++;
switch (ConfEntry->banaction)
{
case DNSBLConfEntry::I_KILL:
{
userrec::QuitUser(ServerInstance, them, std::string("Killed (") + reason + ")");
break;
}
case DNSBLConfEntry::I_KLINE:
{
std::string ban = std::string("*@") + them->GetIPString();
if (show)
ServerInstance->XLines->apply_lines(APPLY_KLINES);
show = ServerInstance->XLines->add_kline(ConfEntry->duration, ServerInstance->Config->ServerName, reason.c_str(), ban.c_str());
FOREACH_MOD(I_OnAddKLine,OnAddKLine(ConfEntry->duration, NULL, reason, ban));
break;
}
case DNSBLConfEntry::I_GLINE:
{
std::string ban = std::string("*@") + them->GetIPString();
show = ServerInstance->XLines->add_gline(ConfEntry->duration, ServerInstance->Config->ServerName, reason.c_str(), ban.c_str());
if (show)
ServerInstance->XLines->apply_lines(APPLY_GLINES);
FOREACH_MOD(I_OnAddGLine,OnAddGLine(ConfEntry->duration, NULL, reason, ban));
break;
}
case DNSBLConfEntry::I_ZLINE:
{
show = ServerInstance->XLines->add_zline(ConfEntry->duration, ServerInstance->Config->ServerName, reason.c_str(), them->GetIPString());
if (show)
ServerInstance->XLines->apply_lines(APPLY_ZLINES);
FOREACH_MOD(I_OnAddZLine,OnAddZLine(ConfEntry->duration, NULL, reason, them->GetIPString()));
break;
}
case DNSBLConfEntry::I_UNKNOWN:
{
break;
}
break;
}
if (show)
{
ServerInstance->WriteOpers("*** Connecting user %s detected as being on a DNS blacklist (%s) with result %d", them->GetFullRealHost(), ConfEntry->name.c_str(), bitmask);
}
}
else
ConfEntry->stats_misses++;
}
else
ConfEntry->stats_misses++;
}
}
virtual void OnError(ResolverError e, const std::string &errormessage)
{
}
virtual ~DNSBLResolver()
{
}
};
class ModuleDNSBL : public Module
{
private:
std::vector<DNSBLConfEntry *> DNSBLConfEntries;
/*
* Convert a string to EnumBanaction
*/
DNSBLConfEntry::EnumBanaction str2banaction(const std::string &action)
{
if(action.compare("KILL")==0)
return DNSBLConfEntry::I_KILL;
if(action.compare("KLINE")==0)
return DNSBLConfEntry::I_KLINE;
if(action.compare("ZLINE")==0)
return DNSBLConfEntry::I_ZLINE;
if(action.compare("GLINE")==0)
return DNSBLConfEntry::I_GLINE;
return DNSBLConfEntry::I_UNKNOWN;
}
public:
ModuleDNSBL(InspIRCd *Me) : Module(Me)
{
ReadConf();
}
virtual ~ModuleDNSBL()
{
ClearEntries();
}
virtual Version GetVersion()
{
return Version(2, 0, 0, 1, VF_VENDOR, API_VERSION);
}
void Implements(char* List)
{
List[I_OnRehash] = List[I_OnUserRegister] = List[I_OnStats] = 1;
}
/** Clear entries and free the mem it was using
*/
void ClearEntries()
{
std::vector<DNSBLConfEntry *>::iterator i;
for (std::vector<DNSBLConfEntry *>::iterator i = DNSBLConfEntries.begin(); i != DNSBLConfEntries.end(); i++)
delete *i;
DNSBLConfEntries.clear();
}
/** Fill our conf vector with data
*/
virtual void ReadConf()
{
ConfigReader *MyConf = new ConfigReader(ServerInstance);
ClearEntries();
for (int i=0; i< MyConf->Enumerate("dnsbl"); i++)
{
DNSBLConfEntry *e = new DNSBLConfEntry();
e->name = MyConf->ReadValue("dnsbl", "name", i);
e->reason = MyConf->ReadValue("dnsbl", "reason", i);
e->domain = MyConf->ReadValue("dnsbl", "domain", i);
e->banaction = str2banaction(MyConf->ReadValue("dnsbl", "action", i));
e->duration = ServerInstance->Duration(MyConf->ReadValue("dnsbl", "duration", i));
e->bitmask = MyConf->ReadInteger("dnsbl", "bitmask", i, false);
/* yeah, logic here is a little messy */
if (e->bitmask <= 0)
{
ServerInstance->WriteOpers("*** DNSBL(#%d): invalid bitmask",i);
}
else if (e->name.empty())
{
ServerInstance->WriteOpers("*** DNSBL(#%d): Invalid name",i);
}
else if (e->domain.empty())
{
ServerInstance->WriteOpers("*** DNSBL(#%d): Invalid domain",i);
}
else if (e->banaction == DNSBLConfEntry::I_UNKNOWN)
{
ServerInstance->WriteOpers("*** DNSBL(#%d): Invalid banaction", i);
}
else
{
if (e->reason.empty())
{
ServerInstance->WriteOpers("*** DNSBL(#%d): empty reason, using defaults",i);
e->reason = "Your IP has been blacklisted.";
}
/* add it, all is ok */
DNSBLConfEntries.push_back(e);
continue;
}
/* delete and drop it, error somewhere */
delete e;
}
delete MyConf;
}
virtual void OnRehash(userrec* user, const std::string ¶meter)
{
ReadConf();
}
virtual int OnUserRegister(userrec* user)
{
/* only do lookups on local users */
if (IS_LOCAL(user))
{
/* following code taken from bopm, reverses an IP address. */
struct in_addr in;
unsigned char a, b, c, d;
char reversedipbuf[128];
std::string reversedip;
bool success = false;
if (!inet_aton(user->GetIPString(), &in))
{
#ifdef IPV6
/* We could have an ipv6 address here */
std::string x = user->GetIPString();
/* Is it a 4in6 address? (Compensate for this kernel kludge that people love) */
if (x.find("0::ffff:") == 0)
{
x.erase(x.begin(), x.begin() + 8);
if (inet_aton(x.c_str(), &in))
success = true;
}
#endif
}
else
{
success = true;
}
if (!success)
return 0;
d = (unsigned char) (in.s_addr >> 24) & 0xFF;
c = (unsigned char) (in.s_addr >> 16) & 0xFF;
b = (unsigned char) (in.s_addr >> 8) & 0xFF;
a = (unsigned char) in.s_addr & 0xFF;
snprintf(reversedipbuf, 128, "%d.%d.%d.%d", d, c, b, a);
reversedip = std::string(reversedipbuf);
// For each DNSBL, we will run through this lookup
for (std::vector<DNSBLConfEntry *>::iterator i = DNSBLConfEntries.begin(); i != DNSBLConfEntries.end(); i++)
{
// Fill hostname with a dnsbl style host (d.c.b.a.domain.tld)
std::string hostname = reversedip + "." + (*i)->domain;
/* now we'd need to fire off lookups for `hostname'. */
bool cached;
DNSBLResolver *r = new DNSBLResolver(this, ServerInstance, hostname, user, user->GetFd(), *i, cached);
ServerInstance->AddResolver(r, cached);
}
}
/* don't do anything with this hot potato */
return 0;
}
virtual int OnStats(char symbol, userrec* user, string_list &results)
{
if (symbol != 'd')
return 0;
unsigned long total_hits = 0, total_misses = 0;
for (std::vector<DNSBLConfEntry*>::iterator i = DNSBLConfEntries.begin(); i != DNSBLConfEntries.end(); i++)
{
total_hits += (*i)->stats_hits;
total_misses += (*i)->stats_misses;
results.push_back(std::string(ServerInstance->Config->ServerName) + " 304 " + user->nick + " :DNSBLSTATS DNSbl \"" + (*i)->name + "\" had " +
ConvToStr((*i)->stats_hits) + " hits and " + ConvToStr((*i)->stats_misses) + " misses");
}
results.push_back(std::string(ServerInstance->Config->ServerName) + " 304 " + user->nick + " :DNSBLSTATS Total hits: " + ConvToStr(total_hits));
results.push_back(std::string(ServerInstance->Config->ServerName) + " 304 " + user->nick + " :DNSBLSTATS Total misses: " + ConvToStr(total_misses));
return 0;
}
};
MODULE_INIT(ModuleDNSBL)
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