/* +------------------------------------+ * | Inspire Internet Relay Chat Daemon | * +------------------------------------+ * * InspIRCd: (C) 2002-2009 InspIRCd Development Team * See: http://wiki.inspircd.org/Credits * * This program is free but copyrighted software; see * the file COPYING for details. * * --------------------------------------------------- */ #include "inspircd.h" #include #include #include "transport.h" #include "m_cap.h" #ifdef WINDOWS #pragma comment(lib, "libgnutls-13.lib") #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 */ /* $CopyInstall: conf/key.pem $(CONPATH) */ /* $CopyInstall: conf/cert.pem $(CONPATH) */ enum issl_status { ISSL_NONE, ISSL_HANDSHAKING_READ, ISSL_HANDSHAKING_WRITE, ISSL_HANDSHAKEN, ISSL_CLOSING, ISSL_CLOSED }; /** Represents an SSL user's extra data */ class issl_session : public classbase { public: issl_session() { sess = NULL; } gnutls_session_t sess; issl_status status; std::string outbuf; }; class CommandStartTLS : public Command { Module* Caller; public: CommandStartTLS (InspIRCd* Instance, Module* mod) : Command(Instance,"STARTTLS", 0, 0, true), Caller(mod) { this->source = "m_ssl_gnutls.so"; } CmdResult Handle (const std::vector ¶meters, User *user) { /* changed from == REG_ALL to catch clients sending STARTTLS * after NICK and USER but before OnUserConnect completes and * give a proper error message (see bug #645) - dz */ if (user->registered != REG_NONE) { user->WriteNumeric(691, "%s :STARTTLS is not permitted after client registration has started", user->nick.c_str()); } else { if (!user->GetIOHook()) { user->WriteNumeric(670, "%s :STARTTLS successful, go ahead with TLS handshake", user->nick.c_str()); user->AddIOHook(Caller); Caller->OnRawSocketAccept(user->GetFd(), NULL, NULL); } else user->WriteNumeric(691, "%s :STARTTLS failure", user->nick.c_str()); } return CMD_FAILURE; } }; class ModuleSSLGnuTLS : public Module { std::set listenports; issl_session* sessions; 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; bool cred_alloc; CommandStartTLS starttls; public: ModuleSSLGnuTLS(InspIRCd* Me) : Module(Me), starttls(Me, this) { ServerInstance->Modules->PublishInterface("BufferedSocketHook", this); sessions = new issl_session[ServerInstance->SE->GetMaxFds()]; gnutls_global_init(); // This must be called once in the program cred_alloc = false; // Needs the flag as it ignores a plain /rehash OnModuleRehash(NULL,"ssl"); // Void return, guess we assume success gnutls_certificate_set_dh_params(x509_cred, dh_params); Implementation eventlist[] = { I_On005Numeric, I_OnRawSocketConnect, I_OnRawSocketAccept, I_OnRawSocketClose, I_OnRawSocketRead, I_OnRawSocketWrite, I_OnCleanup, I_OnBufferFlushed, I_OnRequest, I_OnRehash, I_OnModuleRehash, I_OnPostConnect, I_OnEvent, I_OnHookIO }; ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation)); ServerInstance->AddCommand(&starttls); } virtual void OnRehash(User* user) { ConfigReader Conf(ServerInstance); listenports.clear(); sslports.clear(); for (size_t i = 0; i < ServerInstance->ports.size(); i++) { ListenSocketBase* port = ServerInstance->ports[i]; std::string desc = port->GetDescription(); if (desc != "gnutls") continue; listenports.insert(port); std::string portid = port->GetBindDesc(); ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %s", portid.c_str()); if (port->GetIP() != "127.0.0.1") sslports.append(portid).append(";"); } if (!sslports.empty()) sslports.erase(sslports.end() - 1); } virtual void OnModuleRehash(User* user, const std::string ¶m) { if(param != "ssl") return; OnRehash(user); ConfigReader Conf(ServerInstance); 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] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(cafile))) cafile = confdir + cafile; if ((crlfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(crlfile))) crlfile = confdir + crlfile; if ((certfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(certfile))) certfile = confdir + certfile; if ((keyfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(keyfile))) 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->Logs->Log("m_ssl_gnutls",DEBUG, "m_ssl_gnutls.so: Failed to allocate certificate credentials: %s", gnutls_strerror(ret)); if((ret = gnutls_dh_params_init(&dh_params)) < 0) ServerInstance->Logs->Log("m_ssl_gnutls",DEBUG, "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->Logs->Log("m_ssl_gnutls",DEBUG, "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->Logs->Log("m_ssl_gnutls",DEBUG, "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(); } 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->Logs->Log("m_ssl_gnutls",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->Modules->UnpublishInterface("BufferedSocketHook", this); delete[] sessions; } virtual void OnCleanup(int target_type, void* item) { if(target_type == TYPE_USER) { User* user = static_cast(item); if (user->GetIOHook() == this) { // 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->Users->QuitUser(user, "SSL module unloading"); user->DelIOHook(); } if (user->GetExt("ssl_cert")) { ssl_cert* tofree; user->GetExt("ssl_cert", tofree); delete tofree; user->Shrink("ssl_cert"); } } } virtual Version GetVersion() { return Version("$Id$", VF_VENDOR, API_VERSION); } virtual void On005Numeric(std::string &output) { if (!sslports.empty()) output.append(" SSL=" + sslports); output.append(" STARTTLS"); } virtual void OnHookIO(EventHandler* user, ListenSocketBase* lsb) { if (!user->GetIOHook() && listenports.find(lsb) != listenports.end()) { /* Hook the user with our module */ user->AddIOHook(this); } } virtual const char* OnRequest(Request* request) { ISHRequest* ISR = static_cast(request); if (strcmp("IS_NAME", request->GetId()) == 0) { return "gnutls"; } else if (strcmp("IS_HOOK", request->GetId()) == 0) { const char* ret = "OK"; try { ret = ISR->Sock->AddIOHook(this) ? "OK" : NULL; } catch (ModuleException &e) { return NULL; } return ret; } else if (strcmp("IS_UNHOOK", request->GetId()) == 0) { return ISR->Sock->DelIOHook() ? "OK" : NULL; } else if (strcmp("IS_HSDONE", request->GetId()) == 0) { if (ISR->Sock->GetFd() < 0) return "OK"; issl_session* session = &sessions[ISR->Sock->GetFd()]; return (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE) ? NULL : "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 (static_cast(ServerInstance->SE->GetRef(ISR->Sock->GetFd())) == static_cast(ISR->Sock)) { VerifyCertificate(session, ISR->Sock); return "OK"; } } } } else if (strcmp("GET_FP", request->GetId()) == 0) { if (ISR->Sock->GetFd() > -1) { issl_session* session = &sessions[ISR->Sock->GetFd()]; if (session->sess) { Extensible* ext = ISR->Sock; ssl_cert* certinfo; if (ext->GetExt("ssl_cert",certinfo)) return certinfo->GetFingerprint().c_str(); } } } return NULL; } virtual void OnRawSocketAccept(int fd, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server) { /* Are there any possibilities of an out of range fd? Hope not, but lets be paranoid */ if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1)) return; issl_session* session = &sessions[fd]; /* For STARTTLS: Don't try and init a session on a socket that already has a session */ if (session->sess) return; 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); gnutls_transport_set_ptr(session->sess, reinterpret_cast(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, fd); } 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 > ServerInstance->SE->GetMaxFds() - 1)) return; issl_session* session = &sessions[fd]; 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, reinterpret_cast(fd)); // Give gnutls the fd for the socket. Handshake(session, fd); } 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 > ServerInstance->SE->GetMaxFds())) return; CloseSession(&sessions[fd]); EventHandler* user = ServerInstance->SE->GetRef(fd); if ((user) && (user->GetExt("ssl_cert"))) { 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 > ServerInstance->SE->GetMaxFds() - 1)) 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, fd)) { errno = session->status == ISSL_CLOSING ? EIO : EAGAIN; // Couldn't resume handshake. return -1; } } else if (session->status == ISSL_HANDSHAKING_WRITE) { errno = EAGAIN; MakePollWrite(fd); return -1; } // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN. if (session->status == ISSL_HANDSHAKEN) { unsigned int len = 0; while (len < count) { int ret = gnutls_record_recv(session->sess, buffer + len, count - len); if (ret > 0) { len += ret; } else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED) { break; } else { if (ret != 0) ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT, "m_ssl_gnutls.so: Error while reading on fd %d: %s", fd, gnutls_strerror(ret)); // if ret == 0, client closed connection. readresult = 0; CloseSession(session); return 1; } } readresult = len; if (len) { return 1; } else { errno = EAGAIN; return -1; } } 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 > ServerInstance->SE->GetMaxFds() - 1)) 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, fd); errno = session->status == ISSL_CLOSING ? EIO : 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) { ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT, "m_ssl_gnutls.so: Error while writing to fd %d: %s", fd, gnutls_strerror(ret)); CloseSession(session); } else { errno = EAGAIN; } } else { session->outbuf = session->outbuf.substr(ret); } } if (!session->outbuf.empty()) MakePollWrite(fd); /* Who's smart idea was it to return 1 when we havent written anything? * This fucks the buffer up in BufferedSocket :p */ return ret < 1 ? 0 : ret; } bool Handshake(issl_session* session, int fd) { 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(fd); } } else { // Handshake failed. ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT, "m_ssl_gnutls.so: Handshake failed on fd %d: %s", fd, gnutls_strerror(ret)); 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. EventHandler *extendme = ServerInstance->SE->GetRef(fd); if (extendme) { extendme->Extend("ssl"); } // Change the seesion state session->status = ISSL_HANDSHAKEN; // Finish writing, if any left MakePollWrite(fd); return true; } } virtual void OnPostConnect(User* user) { // This occurs AFTER OnUserConnect so we can be sure the // protocol module has propagated the NICK message. if (user->GetIOHook() == this && (IS_LOCAL(user))) { ssl_cert* certdata = 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.c_str(), cipher.c_str()); } ServerInstance->PI->SendMetaData(user, "ssl", "ON"); if (certdata) ServerInstance->PI->SendMetaData(user, "ssl_cert", certdata->GetMetaLine().c_str()); } } void MakePollWrite(int fd) { //OnRawSocketWrite(fd, NULL, 0); EventHandler* eh = ServerInstance->SE->GetRef(fd); if (eh) ServerInstance->SE->WantWrite(eh); } virtual void OnBufferFlushed(User* user) { if (user->GetIOHook() == this) { 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); } session->outbuf.clear(); session->sess = NULL; session->status = ISSL_NONE; } ssl_cert* VerifyCertificate(issl_session* session, Extensible* user) { if (!session->sess || !user) return NULL; 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->error = std::string(gnutls_strerror(ret)); return certinfo; } certinfo->invalid = (status & GNUTLS_CERT_INVALID); certinfo->unknownsigner = (status & GNUTLS_CERT_SIGNER_NOT_FOUND); certinfo->revoked = (status & GNUTLS_CERT_REVOKED); certinfo->trusted = !(status & GNUTLS_CERT_SIGNER_NOT_CA); /* 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->error = "No X509 keys sent"; return certinfo; } ret = gnutls_x509_crt_init(&cert); if (ret < 0) { certinfo->error = gnutls_strerror(ret); return certinfo; } cert_list_size = 0; cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size); if (cert_list == NULL) { certinfo->error = "No certificate was found"; return certinfo; } /* 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->error = gnutls_strerror(ret); return certinfo; } gnutls_x509_crt_get_dn(cert, name, &name_size); certinfo->dn = name; gnutls_x509_crt_get_issuer_dn(cert, name, &name_size); certinfo->issuer = name; if ((ret = gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_MD5, digest, &digest_size)) < 0) { certinfo->error = gnutls_strerror(ret); } else { certinfo->fingerprint = irc::hex(digest, digest_size); } /* Beware here we do not check for errors. */ if ((gnutls_x509_crt_get_expiration_time(cert) < ServerInstance->Time()) || (gnutls_x509_crt_get_activation_time(cert) > ServerInstance->Time())) { certinfo->error = "Not activated, or expired certificate"; } gnutls_x509_crt_deinit(cert); return certinfo; } void OnEvent(Event* ev) { GenericCapHandler(ev, "tls", "tls"); } void Prioritize() { Module* server = ServerInstance->Modules->Find("m_spanningtree.so"); ServerInstance->Modules->SetPriority(this, I_OnPostConnect, PRIORITY_AFTER, &server); } }; MODULE_INIT(ModuleSSLGnuTLS)