#include #include #include #include #include "inspircd_config.h" #include "configreader.h" #include "users.h" #include "channels.h" #include "modules.h" #include "socket.h" #include "hashcomp.h" #include "inspircd.h" #include "ssl_cert.h" /* $ModDesc: Provides SSL support for clients */ /* $CompileFlags: `libgnutls-config --cflags` */ /* $LinkerFlags: `perl extra/gnutls_rpath.pl` */ /* $ModDep: ssl_cert.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 &portlist) { for(unsigned int i = 0; i < portlist.size(); i++) if(portlist[i] == port) return true; return false; } /** Represents an SSL user's extra data */ class issl_session : public classbase { public: gnutls_session_t sess; issl_status status; std::string outbuf; int inbufoffset; char* inbuf; int fd; }; class ModuleSSLGnuTLS : public Module { ConfigReader* Conf; char* dummy; CullList* culllist; std::vector 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; int dh_bits; public: ModuleSSLGnuTLS(InspIRCd* Me) : Module::Module(Me) { culllist = new CullList(ServerInstance); // 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 if(gnutls_certificate_allocate_credentials(&x509_cred) != 0) ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: Failed to allocate certificate credentials"); // Guessing return meaning if(gnutls_dh_params_init(&dh_params) < 0) ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: Failed to initialise DH parameters"); // Needs the flag as it ignores a plain /rehash OnRehash("ssl"); // Void return, guess we assume success gnutls_certificate_set_dh_params(x509_cred, dh_params); } virtual void OnRehash(const std::string ¶m) { if(param != "ssl") return; Conf = new ConfigReader(ServerInstance); for(unsigned int i = 0; i < listenports.size(); i++) { ServerInstance->Config->DelIOHook(listenports[i]); } listenports.clear(); for(int i = 0; i < Conf->Enumerate("bind"); i++) { // For each tag if(((Conf->ReadValue("bind", "type", i) == "") || (Conf->ReadValue("bind", "type", i) == "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())) { if (ServerInstance->Config->AddIOHook(portno, this)) { listenports.push_back(portno); ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %d", portno); } 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); } } } } std::string confdir(CONFIG_FILE); // +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 == "") cafile = "ca.pem"; if(crlfile == "") crlfile = "crl.pem"; if(certfile == "") certfile = "cert.pem"; if(keyfile == "") 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; if(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", cafile.c_str()); if(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", crlfile.c_str()); // Guessing on the return value of this, manual doesn't say :| if(gnutls_certificate_set_x509_key_file (x509_cred, certfile.c_str(), keyfile.c_str(), GNUTLS_X509_FMT_PEM) < 0) ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: Failed to set X.509 certificate and key files: %s and %s", certfile.c_str(), keyfile.c_str()); // 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. if(gnutls_dh_params_generate2(dh_params, dh_bits) < 0) ServerInstance->Log(DEFAULT, "m_ssl_gnutls.so: Failed to generate DH parameters (%d bits)", dh_bits); } virtual ~ModuleSSLGnuTLS() { gnutls_dh_params_deinit(dh_params); gnutls_certificate_free_credentials(x509_cred); gnutls_global_deinit(); delete culllist; } 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. ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: Adding user %s to cull list", user->nick); culllist->AddItem(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) { // We're being unloaded, kill all the users added to the cull list in OnCleanup int numusers = culllist->Apply(); ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: Killed %d users for unload of GnuTLS SSL module", numusers); for(unsigned int i = 0; i < listenports.size(); i++) ServerInstance->Config->DelIOHook(listenports[i]); } } virtual Version GetVersion() { return Version(1, 1, 0, 0, VF_VENDOR, API_VERSION); } void Implements(char* List) { List[I_OnRawSocketAccept] = List[I_OnRawSocketClose] = List[I_OnRawSocketRead] = List[I_OnRawSocketWrite] = List[I_OnCleanup] = 1; List[I_OnSyncUserMetaData] = List[I_OnDecodeMetaData] = List[I_OnUnloadModule] = List[I_OnRehash] = List[I_OnWhois] = List[I_OnPostConnect] = 1; } virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport) { 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_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any. 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. Handshake(session); } virtual void OnRawSocketClose(int fd) { ServerInstance->Log(DEBUG, "OnRawSocketClose: %d", fd); 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) { issl_session* session = &sessions[fd]; if (!session->sess) { ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: OnRawSocketRead: No session to read from"); readresult = 0; CloseSession(session); return 1; } if (session->status == ISSL_HANDSHAKING_READ) { // The handshake isn't finished, try to finish it. if(Handshake(session)) { // Handshake successfully resumed. ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: OnRawSocketRead: successfully resumed handshake"); } else { // Couldn't resume handshake. ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: OnRawSocketRead: failed to resume handshake"); return -1; } } else if (session->status == ISSL_HANDSHAKING_WRITE) { ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: OnRawSocketRead: handshake wants to write data but we are currently reading"); 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. ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: gnutls_record_recv(sess, inbuf+%d, %d-%d)", session->inbufoffset, inbufsize, session->inbufoffset); int ret = gnutls_record_recv(session->sess, session->inbuf + session->inbufoffset, inbufsize - session->inbufoffset); if (ret == 0) { // Client closed connection. ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: Client closed the connection"); readresult = 0; CloseSession(session); return 1; } else if (ret < 0) { if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED) { ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: OnRawSocketRead: Not all SSL data read: %s", gnutls_strerror(ret)); return -1; } else { ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: OnRawSocketRead: Error reading SSL data: %s", gnutls_strerror(ret)); 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 memcpy(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) { ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: OnRawSocketRead: session closing..."); readresult = 0; } return 1; } virtual int OnRawSocketWrite(int fd, const char* buffer, int count) { issl_session* session = &sessions[fd]; const char* sendbuffer = buffer; if(!session->sess) { ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: OnRawSocketWrite: No session to write to"); CloseSession(session); return 1; } if(session->status == ISSL_HANDSHAKING_WRITE) { // The handshake isn't finished, try to finish it. if(Handshake(session)) { // Handshake successfully resumed. ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: OnRawSocketWrite: successfully resumed handshake"); } else { // Couldn't resume handshake. ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: OnRawSocketWrite: failed to resume handshake"); } } else if(session->status == ISSL_HANDSHAKING_READ) { ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: OnRawSocketWrite: handshake wants to read data but we are currently writing"); } session->outbuf.append(sendbuffer, count); sendbuffer = session->outbuf.c_str(); count = session->outbuf.size(); if(session->status == ISSL_HANDSHAKEN) { int ret = gnutls_record_send(session->sess, sendbuffer, count); if(ret == 0) { ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: OnRawSocketWrite: Client closed the connection"); CloseSession(session); } else if(ret < 0) { if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED) { ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: OnRawSocketWrite: Not all SSL data written: %s", gnutls_strerror(ret)); } else { ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: OnRawSocketWrite: Error writing SSL data: %s", gnutls_strerror(ret)); CloseSession(session); } } else { session->outbuf = session->outbuf.substr(ret); } } else if(session->status == ISSL_CLOSING) { ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: OnRawSocketWrite: session closing..."); } return 1; } // :kenny.chatspike.net 320 Om Epy|AFK :is a Secure Connection virtual void OnWhois(userrec* source, userrec* dest) { // 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) { // 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, "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; ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: Handshake needs resuming (reading) later, error string: %s", gnutls_strerror(ret)); } else { // gnutls_handshake() wants to write() again. session->status = ISSL_HANDSHAKING_WRITE; ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: Handshake needs resuming (writing) later, error string: %s", gnutls_strerror(ret)); MakePollWrite(session); } } else { // Handshake failed. CloseSession(session); ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: Handshake failed, error string: %s", gnutls_strerror(ret)); session->status = ISSL_CLOSING; } return false; } else { // Handshake complete. ServerInstance->Log(DEBUG, "m_ssl_gnutls.so: Handshake completed"); // 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* metadata = new std::deque; 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); } } void MakePollWrite(issl_session* session) { OnRawSocketWrite(session->fd, 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, userrec* user) { 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))); user->WriteServ("NOTICE %s :*** Your SSL Certificate fingerprint is: %s", user->nick, irc::hex(digest, digest_size).c_str()); } /* 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; } }; class ModuleSSLGnuTLSFactory : public ModuleFactory { public: ModuleSSLGnuTLSFactory() { } ~ModuleSSLGnuTLSFactory() { } virtual Module * CreateModule(InspIRCd* Me) { return new ModuleSSLGnuTLS(Me); } }; extern "C" void * init_module( void ) { return new ModuleSSLGnuTLSFactory; }