Main Page | Namespace List | Class Hierarchy | Alphabetical List | Class List | Directories | File List | Namespace Members | Class Members | File Members

home » brain » inspircd-cvs » 1_1_stable » src » modules » extra

m_ssl_gnutls.cpp

Go to the documentation of this file.

/*       +------------------------------------+
 *       | Inspire Internet Relay Chat Daemon |
 *       +------------------------------------+
 *
 *  InspIRCd: (C) 2002-2008 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 <gnutls/gnutls.h>
#include <gnutls/x509.h>

#include "inspircd_config.h"
#include "configreader.h"
#include "users.h"
#include "channels.h"
#include "modules.h"
#include "socket.h"
#include "hashcomp.h"
#include "transport.h"

#ifdef WINDOWS
#pragma comment(lib, "libgnutls-13.lib")
#undef MAX_DESCRIPTORS
#define MAX_DESCRIPTORS 10000
#endif

/* $ModDesc: Provides SSL support for clients */
/* $CompileFlags: pkgconfincludes("gnutls","/gnutls/gnutls.h","") */
/* $LinkerFlags: rpath("pkg-config --libs gnutls") pkgconflibs("gnutls","/libgnutls.so","-lgnutls") */
/* $ModDep: transport.h */

enum issl_status { ISSL_NONE, ISSL_HANDSHAKING_READ, ISSL_HANDSHAKING_WRITE, ISSL_HANDSHAKEN, ISSL_CLOSING, ISSL_CLOSED };

bool isin(int port, const std::vector<int> &portlist)
{
        for(unsigned int i = 0; i < portlist.size(); i++)
                if(portlist[i] == port)
                        return true;

        return false;
}

class issl_session : public classbase
{
public:
        issl_session()
        {
                sess = NULL;
        }
        gnutls_session_t sess;
        issl_status status;
        std::string outbuf;
        int inbufoffset;
        char* inbuf;
        int fd;
};

class ModuleSSLGnuTLS : public Module
{

        ConfigReader* Conf;

        char* dummy;

        std::vector<int> listenports;

        int inbufsize;
        issl_session sessions[MAX_DESCRIPTORS];

        gnutls_certificate_credentials x509_cred;
        gnutls_dh_params dh_params;

        std::string keyfile;
        std::string certfile;
        std::string cafile;
        std::string crlfile;
        std::string sslports;
        int dh_bits;

        int clientactive;
        bool cred_alloc;

 public:

        ModuleSSLGnuTLS(InspIRCd* Me)
                : Module(Me)
        {
                ServerInstance->PublishInterface("InspSocketHook", this);

                // Not rehashable...because I cba to reduce all the sizes of existing buffers.
                inbufsize = ServerInstance->Config->NetBufferSize;

                gnutls_global_init(); // This must be called once in the program
                
                cred_alloc = false;
                // Needs the flag as it ignores a plain /rehash
                OnRehash(NULL,"ssl");

                // Void return, guess we assume success
                gnutls_certificate_set_dh_params(x509_cred, dh_params);
        }

        virtual void OnRehash(userrec* user, const std::string &param)
        {
                Conf = new ConfigReader(ServerInstance);

                for(unsigned int i = 0; i < listenports.size(); i++)
                {
                        ServerInstance->Config->DelIOHook(listenports[i]);
                }

                listenports.clear();
                clientactive = 0;
                sslports.clear();

                for(int i = 0; i < Conf->Enumerate("bind"); i++)
                {
                        // For each <bind> tag
                        std::string x = Conf->ReadValue("bind", "type", i);
                        if(((x.empty()) || (x == "clients")) && (Conf->ReadValue("bind", "ssl", i) == "gnutls"))
                        {
                                // Get the port we're meant to be listening on with SSL
                                std::string port = Conf->ReadValue("bind", "port", i);
                                irc::portparser portrange(port, false);
                                long portno = -1;
                                while ((portno = portrange.GetToken()))
                                {
                                        clientactive++;
                                        try
                                        {
                                                if (ServerInstance->Config->AddIOHook(portno, this))
                                                {
                                                        listenports.push_back(portno);
                                                        for (size_t i = 0; i < ServerInstance->Config->ports.size(); i++)
                                                                if (ServerInstance->Config->ports[i]->GetPort() == portno)
                                                                        ServerInstance->Config->ports[i]->SetDescription("ssl");
                                                        ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %d", portno);
                                                        sslports.append("*:").append(ConvToStr(portno)).append(";");
                                                }
                                                else
                                                {
                                                        ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: FAILED to enable SSL on port %d, maybe you have another ssl or similar module loaded?", portno);
                                                }
                                        }
                                        catch (ModuleException &e)
                                        {
                                                ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: FAILED to enable SSL on port %d: %s. Maybe it's already hooked by the same port on a different IP, or you have an other SSL or similar module loaded?", portno, e.GetReason());
                                        }
                                }
                        }
                }

                if(param != "ssl")
                {
                        delete Conf;
                        return;
                }

                std::string confdir(ServerInstance->ConfigFileName);
                // +1 so we the path ends with a /
                confdir = confdir.substr(0, confdir.find_last_of('/') + 1);

                cafile  = Conf->ReadValue("gnutls", "cafile", 0);
                crlfile = Conf->ReadValue("gnutls", "crlfile", 0);
                certfile        = Conf->ReadValue("gnutls", "certfile", 0);
                keyfile = Conf->ReadValue("gnutls", "keyfile", 0);
                dh_bits = Conf->ReadInteger("gnutls", "dhbits", 0, false);

                // Set all the default values needed.
                if (cafile.empty())
                        cafile = "ca.pem";

                if (crlfile.empty())
                        crlfile = "crl.pem";

                if (certfile.empty())
                        certfile = "cert.pem";

                if (keyfile.empty())
                        keyfile = "key.pem";

                if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
                        dh_bits = 1024;

                // Prepend relative paths with the path to the config directory.
                if(cafile[0] != '/')
                        cafile = confdir + cafile;

                if(crlfile[0] != '/')
                        crlfile = confdir + crlfile;

                if(certfile[0] != '/')
                        certfile = confdir + certfile;

                if(keyfile[0] != '/')
                        keyfile = confdir + keyfile;

                int ret;
                
                if (cred_alloc)
                {
                        // Deallocate the old credentials
                        gnutls_dh_params_deinit(dh_params);
                        gnutls_certificate_free_credentials(x509_cred);
                }
                else
                        cred_alloc = true;
                
                if((ret = gnutls_certificate_allocate_credentials(&x509_cred)) < 0)
                        ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: Failed to allocate certificate credentials: %s", gnutls_strerror(ret));
                
                if((ret = gnutls_dh_params_init(&dh_params)) < 0)
                        ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: Failed to initialise DH parameters: %s", gnutls_strerror(ret));
                
                if((ret =gnutls_certificate_set_x509_trust_file(x509_cred, cafile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
                        ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: Failed to set X.509 trust file '%s': %s", cafile.c_str(), gnutls_strerror(ret));

                if((ret = gnutls_certificate_set_x509_crl_file (x509_cred, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
                        ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: Failed to set X.509 CRL file '%s': %s", crlfile.c_str(), gnutls_strerror(ret));

                if((ret = gnutls_certificate_set_x509_key_file (x509_cred, certfile.c_str(), keyfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
                {
                        // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
                        throw ModuleException("Unable to load GnuTLS server certificate (" + certfile + ", key: " + keyfile + "): " + std::string(gnutls_strerror(ret)));
                }

                // This may be on a large (once a day or week) timer eventually.
                GenerateDHParams();

                DELETE(Conf);
        }

        void GenerateDHParams()
        {
                // Generate Diffie Hellman parameters - for use with DHE
                // kx algorithms. These should be discarded and regenerated
                // once a day, once a week or once a month. Depending on the
                // security requirements.

                int ret;

                if((ret = gnutls_dh_params_generate2(dh_params, dh_bits)) < 0)
                        ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: Failed to generate DH parameters (%d bits): %s", dh_bits, gnutls_strerror(ret));
        }

        virtual ~ModuleSSLGnuTLS()
        {
                gnutls_dh_params_deinit(dh_params);
                gnutls_certificate_free_credentials(x509_cred);
                gnutls_global_deinit();
                ServerInstance->UnpublishInterface("InspSocketHook", this);
        }

        virtual void OnCleanup(int target_type, void* item)
        {
                if(target_type == TYPE_USER)
                {
                        userrec* user = (userrec*)item;

                        if(user->GetExt("ssl", dummy) && isin(user->GetPort(), listenports))
                        {
                                // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
                                // Potentially there could be multiple SSL modules loaded at once on different ports.
                                userrec::QuitUser(ServerInstance, user, "SSL module unloading");
                        }
                        if (user->GetExt("ssl_cert", dummy) && isin(user->GetPort(), listenports))
                        {
                                ssl_cert* tofree;
                                user->GetExt("ssl_cert", tofree);
                                delete tofree;
                                user->Shrink("ssl_cert");
                        }
                }
        }

        virtual void OnUnloadModule(Module* mod, const std::string &name)
        {
                if(mod == this)
                {
                        for(unsigned int i = 0; i < listenports.size(); i++)
                        {
                                ServerInstance->Config->DelIOHook(listenports[i]);
                                for (size_t j = 0; j < ServerInstance->Config->ports.size(); j++)
                                        if (ServerInstance->Config->ports[j]->GetPort() == listenports[i])
                                                ServerInstance->Config->ports[j]->SetDescription("plaintext");
                        }
                }
        }

        virtual Version GetVersion()
        {
                return Version(1, 1, 0, 0, VF_VENDOR, API_VERSION);
        }

        void Implements(char* List)
        {
                List[I_On005Numeric] = List[I_OnRawSocketConnect] = List[I_OnRawSocketAccept] = List[I_OnRawSocketClose] = List[I_OnRawSocketRead] = List[I_OnRawSocketWrite] = List[I_OnCleanup] = 1;
                List[I_OnBufferFlushed] = List[I_OnRequest] = List[I_OnSyncUserMetaData] = List[I_OnDecodeMetaData] = List[I_OnUnloadModule] = List[I_OnRehash] = List[I_OnWhois] = List[I_OnPostConnect] = 1;
        }

        virtual void On005Numeric(std::string &output)
        {
                output.append(" SSL=" + sslports);
        }

        virtual char* OnRequest(Request* request)
        {
                ISHRequest* ISR = (ISHRequest*)request;
                if (strcmp("IS_NAME", request->GetId()) == 0)
                {
                        return "gnutls";
                }
                else if (strcmp("IS_HOOK", request->GetId()) == 0)
                {
                        char* ret = "OK";
                        try
                        {
                                ret = ServerInstance->Config->AddIOHook((Module*)this, (InspSocket*)ISR->Sock) ? (char*)"OK" : NULL;
                        }
                        catch (ModuleException &e)
                        {
                                return NULL;
                        }
                        return ret;
                }
                else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
                {
                        return ServerInstance->Config->DelIOHook((InspSocket*)ISR->Sock) ? (char*)"OK" : NULL;
                }
                else if (strcmp("IS_HSDONE", request->GetId()) == 0)
                {
                        if (ISR->Sock->GetFd() < 0)
                                return (char*)"OK";

                        issl_session* session = &sessions[ISR->Sock->GetFd()];
                        return (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE) ? NULL : (char*)"OK";
                }
                else if (strcmp("IS_ATTACH", request->GetId()) == 0)
                {
                        if (ISR->Sock->GetFd() > -1)
                        {
                                issl_session* session = &sessions[ISR->Sock->GetFd()];
                                if (session->sess)
                                {
                                        if ((Extensible*)ServerInstance->FindDescriptor(ISR->Sock->GetFd()) == (Extensible*)(ISR->Sock))
                                        {
                                                VerifyCertificate(session, (InspSocket*)ISR->Sock);
                                                return "OK";
                                        }
                                }
                        }
                }
                return NULL;
        }


        virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
        {
                /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
                if ((fd < 0) || (fd > MAX_DESCRIPTORS))
                        return;

                issl_session* session = &sessions[fd];

                session->fd = fd;
                session->inbuf = new char[inbufsize];
                session->inbufoffset = 0;

                gnutls_init(&session->sess, GNUTLS_SERVER);

                gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
                gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
                gnutls_dh_set_prime_bits(session->sess, dh_bits);

                /* This is an experimental change to avoid a warning on 64bit systems about casting between integer and pointer of different sizes
                 * This needs testing, but it's easy enough to rollback if need be
                 * Old: gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.
                 * New: gnutls_transport_set_ptr(session->sess, &fd); // Give gnutls the fd for the socket.
                 *
                 * With testing this seems to...not work :/
                 */

                gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.

                gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.

                Handshake(session);
        }

        virtual void OnRawSocketConnect(int fd)
        {
                /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
                if ((fd < 0) || (fd > MAX_DESCRIPTORS))
                        return;

                issl_session* session = &sessions[fd];

                session->fd = fd;
                session->inbuf = new char[inbufsize];
                session->inbufoffset = 0;

                gnutls_init(&session->sess, GNUTLS_CLIENT);

                gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
                gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
                gnutls_dh_set_prime_bits(session->sess, dh_bits);
                gnutls_transport_set_ptr(session->sess, (gnutls_transport_ptr_t) fd); // Give gnutls the fd for the socket.

                Handshake(session);
        }

        virtual void OnRawSocketClose(int fd)
        {
                /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
                if ((fd < 0) || (fd > MAX_DESCRIPTORS))
                        return;

                CloseSession(&sessions[fd]);

                EventHandler* user = ServerInstance->SE->GetRef(fd);

                if ((user) && (user->GetExt("ssl_cert", dummy)))
                {
                        ssl_cert* tofree;
                        user->GetExt("ssl_cert", tofree);
                        delete tofree;
                        user->Shrink("ssl_cert");
                }
        }

        virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
        {
                /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
                if ((fd < 0) || (fd > MAX_DESCRIPTORS))
                        return 0;

                issl_session* session = &sessions[fd];

                if (!session->sess)
                {
                        readresult = 0;
                        CloseSession(session);
                        return 1;
                }

                if (session->status == ISSL_HANDSHAKING_READ)
                {
                        // The handshake isn't finished, try to finish it.

                        if(!Handshake(session))
                        {
                                // Couldn't resume handshake.
                                return -1;
                        }
                }
                else if (session->status == ISSL_HANDSHAKING_WRITE)
                {
                        errno = EAGAIN;
                        MakePollWrite(session);
                        return -1;
                }

                // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.

                if (session->status == ISSL_HANDSHAKEN)
                {
                        // Is this right? Not sure if the unencrypted data is garaunteed to be the same length.
                        // Read into the inbuffer, offset from the beginning by the amount of data we have that insp hasn't taken yet.
                        int ret = gnutls_record_recv(session->sess, session->inbuf + session->inbufoffset, inbufsize - session->inbufoffset);

                        if (ret == 0)
                        {
                                // Client closed connection.
                                readresult = 0;
                                CloseSession(session);
                                return 1;
                        }
                        else if (ret < 0)
                        {
                                if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
                                {
                                        errno = EAGAIN;
                                        return -1;
                                }
                                else
                                {
                                        readresult = 0;
                                        CloseSession(session);
                                }
                        }
                        else
                        {
                                // Read successfully 'ret' bytes into inbuf + inbufoffset
                                // There are 'ret' + 'inbufoffset' bytes of data in 'inbuf'
                                // 'buffer' is 'count' long

                                unsigned int length = ret + session->inbufoffset;

                                if(count <= length)
                                {
                                        memcpy(buffer, session->inbuf, count);
                                        // Move the stuff left in inbuf to the beginning of it
                                        memmove(session->inbuf, session->inbuf + count, (length - count));
                                        // Now we need to set session->inbufoffset to the amount of data still waiting to be handed to insp.
                                        session->inbufoffset = length - count;
                                        // Insp uses readresult as the count of how much data there is in buffer, so:
                                        readresult = count;
                                }
                                else
                                {
                                        // There's not as much in the inbuf as there is space in the buffer, so just copy the whole thing.
                                        memcpy(buffer, session->inbuf, length);
                                        // Zero the offset, as there's nothing there..
                                        session->inbufoffset = 0;
                                        // As above
                                        readresult = length;
                                }
                        }
                }
                else if(session->status == ISSL_CLOSING)
                        readresult = 0;

                return 1;
        }

        virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
        {
                /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */
                if ((fd < 0) || (fd > MAX_DESCRIPTORS))
                        return 0;

                issl_session* session = &sessions[fd];
                const char* sendbuffer = buffer;

                if (!session->sess)
                {
                        CloseSession(session);
                        return 1;
                }

                session->outbuf.append(sendbuffer, count);
                sendbuffer = session->outbuf.c_str();
                count = session->outbuf.size();

                if (session->status == ISSL_HANDSHAKING_WRITE || session->status == ISSL_HANDSHAKING_READ)
                {
                        // The handshake isn't finished, try to finish it.
                        Handshake(session);
                        errno = EAGAIN;
                        return -1;
                }

                int ret = 0;

                if (session->status == ISSL_HANDSHAKEN)
                {
                        ret = gnutls_record_send(session->sess, sendbuffer, count);

                        if (ret == 0)
                        {
                                CloseSession(session);
                        }
                        else if (ret < 0)
                        {
                                if(ret != GNUTLS_E_AGAIN && ret != GNUTLS_E_INTERRUPTED)
                                {
                                        CloseSession(session);
                                }
                                else
                                {
                                        errno = EAGAIN;
                                }
                        }
                        else
                        {
                                session->outbuf = session->outbuf.substr(ret);
                        }
                }

                MakePollWrite(session);

                /* Who's smart idea was it to return 1 when we havent written anything?
                 * This fucks the buffer up in InspSocket :p
                 */
                return ret < 1 ? 0 : ret;
        }

        // :kenny.chatspike.net 320 Om Epy|AFK :is a Secure Connection
        virtual void OnWhois(userrec* source, userrec* dest)
        {
                if (!clientactive)
                        return;

                // Bugfix, only send this numeric for *our* SSL users
                if(dest->GetExt("ssl", dummy) || (IS_LOCAL(dest) &&  isin(dest->GetPort(), listenports)))
                {
                        ServerInstance->SendWhoisLine(source, dest, 320, "%s %s :is using a secure connection", source->nick, dest->nick);
                }
        }

        virtual void OnSyncUserMetaData(userrec* user, Module* proto, void* opaque, const std::string &extname, bool displayable)
        {
                // check if the linking module wants to know about OUR metadata
                if(extname == "ssl")
                {
                        // check if this user has an swhois field to send
                        if(user->GetExt(extname, dummy))
                        {
                                // call this function in the linking module, let it format the data how it
                                // sees fit, and send it on its way. We dont need or want to know how.
                                proto->ProtoSendMetaData(opaque, TYPE_USER, user, extname, displayable ? "Enabled" : "ON");
                        }
                }
        }

        virtual void OnDecodeMetaData(int target_type, void* target, const std::string &extname, const std::string &extdata)
        {
                // check if its our metadata key, and its associated with a user
                if ((target_type == TYPE_USER) && (extname == "ssl"))
                {
                        userrec* dest = (userrec*)target;
                        // if they dont already have an ssl flag, accept the remote server's
                        if (!dest->GetExt(extname, dummy))
                        {
                                dest->Extend(extname, "ON");
                        }
                }
        }

        bool Handshake(issl_session* session)
        {
                int ret = gnutls_handshake(session->sess);

                if (ret < 0)
                {
                        if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
                        {
                                // Handshake needs resuming later, read() or write() would have blocked.

                                if(gnutls_record_get_direction(session->sess) == 0)
                                {
                                        // gnutls_handshake() wants to read() again.
                                        session->status = ISSL_HANDSHAKING_READ;
                                }
                                else
                                {
                                        // gnutls_handshake() wants to write() again.
                                        session->status = ISSL_HANDSHAKING_WRITE;
                                        MakePollWrite(session);
                                }
                        }
                        else
                        {
                                // Handshake failed.
                                CloseSession(session);
                                session->status = ISSL_CLOSING;
                        }

                        return false;
                }
                else
                {
                        // Handshake complete.
                        // This will do for setting the ssl flag...it could be done earlier if it's needed. But this seems neater.
                        userrec* extendme = ServerInstance->FindDescriptor(session->fd);
                        if (extendme)
                        {
                                if (!extendme->GetExt("ssl", dummy))
                                        extendme->Extend("ssl", "ON");
                        }

                        // Change the seesion state
                        session->status = ISSL_HANDSHAKEN;

                        // Finish writing, if any left
                        MakePollWrite(session);

                        return true;
                }
        }

        virtual void OnPostConnect(userrec* user)
        {
                // This occurs AFTER OnUserConnect so we can be sure the
                // protocol module has propogated the NICK message.
                if ((user->GetExt("ssl", dummy)) && (IS_LOCAL(user)))
                {
                        // Tell whatever protocol module we're using that we need to inform other servers of this metadata NOW.
                        std::deque<std::string>* metadata = new std::deque<std::string>;
                        metadata->push_back(user->nick);
                        metadata->push_back("ssl");             // The metadata id
                        metadata->push_back("ON");              // The value to send
                        Event* event = new Event((char*)metadata,(Module*)this,"send_metadata");
                        event->Send(ServerInstance);            // Trigger the event. We don't care what module picks it up.
                        DELETE(event);
                        DELETE(metadata);

                        VerifyCertificate(&sessions[user->GetFd()],user);
                        if (sessions[user->GetFd()].sess)
                        {
                                std::string cipher = gnutls_kx_get_name(gnutls_kx_get(sessions[user->GetFd()].sess));
                                cipher.append("-").append(gnutls_cipher_get_name(gnutls_cipher_get(sessions[user->GetFd()].sess))).append("-");
                                cipher.append(gnutls_mac_get_name(gnutls_mac_get(sessions[user->GetFd()].sess)));
                                user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick, cipher.c_str());
                        }
                }
        }

        void MakePollWrite(issl_session* session)
        {
                //OnRawSocketWrite(session->fd, NULL, 0);
                EventHandler* eh = ServerInstance->FindDescriptor(session->fd);
                if (eh)
                        ServerInstance->SE->WantWrite(eh);
        }

        virtual void OnBufferFlushed(userrec* user)
        {
                if (user->GetExt("ssl"))
                {
                        issl_session* session = &sessions[user->GetFd()];
                        if (session && session->outbuf.size())
                                OnRawSocketWrite(user->GetFd(), NULL, 0);
                }
        }

        void CloseSession(issl_session* session)
        {
                if(session->sess)
                {
                        gnutls_bye(session->sess, GNUTLS_SHUT_WR);
                        gnutls_deinit(session->sess);
                }

                if(session->inbuf)
                {
                        delete[] session->inbuf;
                }

                session->outbuf.clear();
                session->inbuf = NULL;
                session->sess = NULL;
                session->status = ISSL_NONE;
        }

        void VerifyCertificate(issl_session* session, Extensible* user)
        {
                if (!session->sess || !user)
                        return;

                unsigned int status;
                const gnutls_datum_t* cert_list;
                int ret;
                unsigned int cert_list_size;
                gnutls_x509_crt_t cert;
                char name[MAXBUF];
                unsigned char digest[MAXBUF];
                size_t digest_size = sizeof(digest);
                size_t name_size = sizeof(name);
                ssl_cert* certinfo = new ssl_cert;

                user->Extend("ssl_cert",certinfo);

                /* This verification function uses the trusted CAs in the credentials
                 * structure. So you must have installed one or more CA certificates.
                 */
                ret = gnutls_certificate_verify_peers2(session->sess, &status);

                if (ret < 0)
                {
                        certinfo->data.insert(std::make_pair("error",std::string(gnutls_strerror(ret))));
                        return;
                }

                if (status & GNUTLS_CERT_INVALID)
                {
                        certinfo->data.insert(std::make_pair("invalid",ConvToStr(1)));
                }
                else
                {
                        certinfo->data.insert(std::make_pair("invalid",ConvToStr(0)));
                }
                if (status & GNUTLS_CERT_SIGNER_NOT_FOUND)
                {
                        certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(1)));
                }
                else
                {
                        certinfo->data.insert(std::make_pair("unknownsigner",ConvToStr(0)));
                }
                if (status & GNUTLS_CERT_REVOKED)
                {
                        certinfo->data.insert(std::make_pair("revoked",ConvToStr(1)));
                }
                else
                {
                        certinfo->data.insert(std::make_pair("revoked",ConvToStr(0)));
                }
                if (status & GNUTLS_CERT_SIGNER_NOT_CA)
                {
                        certinfo->data.insert(std::make_pair("trusted",ConvToStr(0)));
                }
                else
                {
                        certinfo->data.insert(std::make_pair("trusted",ConvToStr(1)));
                }

                /* Up to here the process is the same for X.509 certificates and
                 * OpenPGP keys. From now on X.509 certificates are assumed. This can
                 * be easily extended to work with openpgp keys as well.
                 */
                if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
                {
                        certinfo->data.insert(std::make_pair("error","No X509 keys sent"));
                        return;
                }

                ret = gnutls_x509_crt_init(&cert);
                if (ret < 0)
                {
                        certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
                        return;
                }

                cert_list_size = 0;
                cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
                if (cert_list == NULL)
                {
                        certinfo->data.insert(std::make_pair("error","No certificate was found"));
                        return;
                }

                /* This is not a real world example, since we only check the first
                 * certificate in the given chain.
                 */

                ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
                if (ret < 0)
                {
                        certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
                        return;
                }

                gnutls_x509_crt_get_dn(cert, name, &name_size);

                certinfo->data.insert(std::make_pair("dn",name));

                gnutls_x509_crt_get_issuer_dn(cert, name, &name_size);

                certinfo->data.insert(std::make_pair("issuer",name));

                if ((ret = gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_MD5, digest, &digest_size)) < 0)
                {
                        certinfo->data.insert(std::make_pair("error",gnutls_strerror(ret)));
                }
                else
                {
                        certinfo->data.insert(std::make_pair("fingerprint",irc::hex(digest, digest_size)));
                }

                /* Beware here we do not check for errors.
                 */
                if ((gnutls_x509_crt_get_expiration_time(cert) < time(0)) || (gnutls_x509_crt_get_activation_time(cert) > time(0)))
                {
                        certinfo->data.insert(std::make_pair("error","Not activated, or expired certificate"));
                }

                gnutls_x509_crt_deinit(cert);

                return;
        }

};

MODULE_INIT(ModuleSSLGnuTLS);