/* +------------------------------------+ * | 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 }; static gnutls_x509_crt_t x509_cert; static gnutls_x509_privkey_t x509_key; static int cert_callback (gnutls_session_t session, const gnutls_datum_t * req_ca_rdn, int nreqs, const gnutls_pk_algorithm_t * sign_algos, int sign_algos_length, gnutls_retr_st * st) { st->type = GNUTLS_CRT_X509; st->ncerts = 1; st->cert.x509 = &x509_cert; st->key.x509 = x509_key; st->deinit_all = 0; return 0; } static ssize_t gnutls_pull_wrapper(gnutls_transport_ptr_t user_wrap, void* buffer, size_t size) { StreamSocket* user = reinterpret_cast(user_wrap); if (user->GetEventMask() & FD_READ_WILL_BLOCK) { errno = EAGAIN; return -1; } int rv = recv(user->GetFd(), buffer, size, 0); if (rv < (int)size) ServerInstance->SE->ChangeEventMask(user, FD_READ_WILL_BLOCK); return rv; } static ssize_t gnutls_push_wrapper(gnutls_transport_ptr_t user_wrap, const void* buffer, size_t size) { StreamSocket* user = reinterpret_cast(user_wrap); if (user->GetEventMask() & FD_WRITE_WILL_BLOCK) { errno = EAGAIN; return -1; } int rv = send(user->GetFd(), buffer, size, 0); if (rv < (int)size) ServerInstance->SE->ChangeEventMask(user, FD_WRITE_WILL_BLOCK); return rv; } /** Represents an SSL user's extra data */ class issl_session : public classbase { public: issl_session() { sess = NULL; } gnutls_session_t sess; issl_status status; }; class CommandStartTLS : public Command { public: CommandStartTLS (Module* mod) : Command(mod, "STARTTLS") { works_before_reg = true; } 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(creator); creator->OnStreamSocketAccept(user, 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; GenericCap capHandler; public: ModuleSSLGnuTLS() : starttls(this), capHandler(this, "tls") { ServerInstance->Modules->PublishInterface("BufferedSocketHook", this); sessions = new issl_session[ServerInstance->SE->GetMaxFds()]; gnutls_global_init(); // This must be called once in the program gnutls_x509_crt_init(&x509_cert); gnutls_x509_privkey_init(&x509_key); 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_OnRequest, I_OnRehash, I_OnModuleRehash, I_OnPostConnect, I_OnEvent, I_OnHookIO }; ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation)); ServerInstance->AddCommand(&starttls); } void OnRehash(User* user) { ConfigReader Conf; 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); } void OnModuleRehash(User* user, const std::string ¶m) { if(param != "ssl") return; OnRehash(user); ConfigReader Conf; 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_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)); FileReader reader; reader.LoadFile(certfile); std::string cert_string = reader.Contents(); gnutls_datum_t cert_datum = { (unsigned char*)cert_string.data(), cert_string.length() }; reader.LoadFile(keyfile); std::string key_string = reader.Contents(); gnutls_datum_t key_datum = { (unsigned char*)key_string.data(), key_string.length() }; // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException if((ret = gnutls_x509_crt_import(x509_cert, &cert_datum, GNUTLS_X509_FMT_PEM)) < 0) throw ModuleException("Unable to load GnuTLS server certificate (" + certfile + "): " + std::string(gnutls_strerror(ret))); if((ret = gnutls_x509_privkey_import(x509_key, &key_datum, GNUTLS_X509_FMT_PEM)) < 0) throw ModuleException("Unable to load GnuTLS server private key (" + keyfile + "): " + std::string(gnutls_strerror(ret))); if((ret = gnutls_certificate_set_x509_key(x509_cred, &x509_cert, 1, x509_key)) < 0) throw ModuleException("Unable to set GnuTLS cert/key pair: " + std::string(gnutls_strerror(ret))); gnutls_certificate_client_set_retrieve_function (x509_cred, cert_callback); if((ret = gnutls_dh_params_init(&dh_params)) < 0) ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to initialise DH parameters: %s", 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)); } ~ModuleSSLGnuTLS() { gnutls_x509_crt_deinit(x509_cert); gnutls_x509_privkey_deinit(x509_key); gnutls_dh_params_deinit(dh_params); gnutls_certificate_free_credentials(x509_cred); gnutls_global_deinit(); ServerInstance->Modules->UnpublishInterface("BufferedSocketHook", this); delete[] sessions; } 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(); } } } Version GetVersion() { return Version("Provides SSL support for clients", VF_VENDOR, API_VERSION); } void On005Numeric(std::string &output) { if (!sslports.empty()) output.append(" SSL=" + sslports); output.append(" STARTTLS"); } void OnHookIO(StreamSocket* user, ListenSocketBase* lsb) { if (!user->GetIOHook() && listenports.find(lsb) != listenports.end()) { /* Hook the user with our module */ user->AddIOHook(this); } } 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) { ISR->Sock->AddIOHook(this); return "OK"; } else if (strcmp("IS_UNHOOK", request->GetId()) == 0) { ISR->Sock->DelIOHook(); return "OK"; } 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)) { return "OK"; } } } } else if (strcmp("GET_CERT", request->GetId()) == 0) { Module* sslinfo = ServerInstance->Modules->Find("m_sslinfo.so"); if (sslinfo) return sslinfo->OnRequest(request); } return NULL; } void OnStreamSocketAccept(StreamSocket* user, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server) { int fd = user->GetFd(); 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(user)); gnutls_transport_set_push_function(session->sess, gnutls_push_wrapper); gnutls_transport_set_pull_function(session->sess, gnutls_pull_wrapper); gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any. Handshake(session, user); } void OnStreamSocketConnect(StreamSocket* user) { issl_session* session = &sessions[user->GetFd()]; 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(user)); gnutls_transport_set_push_function(session->sess, gnutls_push_wrapper); gnutls_transport_set_pull_function(session->sess, gnutls_pull_wrapper); Handshake(session, user); } void OnStreamSocketClose(StreamSocket* user) { CloseSession(&sessions[user->GetFd()]); } int OnStreamSocketRead(StreamSocket* user, std::string& recvq) { issl_session* session = &sessions[user->GetFd()]; if (!session->sess) { CloseSession(session); user->SetError("No SSL session"); return -1; } if (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE) { // The handshake isn't finished, try to finish it. if(!Handshake(session, user)) { if (session->status != ISSL_CLOSING) return 0; user->SetError("Handshake Failed"); return -1; } } // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN. if (session->status == ISSL_HANDSHAKEN) { char* buffer = ServerInstance->GetReadBuffer(); size_t bufsiz = ServerInstance->Config->NetBufferSize; int ret = gnutls_record_recv(session->sess, buffer, bufsiz); if (ret > 0) { recvq.append(buffer, ret); return 1; } else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED) { return 0; } else if (ret == 0) { user->SetError("SSL Connection closed"); CloseSession(session); return -1; } else { user->SetError(gnutls_strerror(ret)); CloseSession(session); return -1; } } else if (session->status == ISSL_CLOSING) return -1; return 0; } int OnStreamSocketWrite(StreamSocket* user, std::string& sendq) { issl_session* session = &sessions[user->GetFd()]; if (!session->sess) { CloseSession(session); user->SetError("No SSL session"); return -1; } if (session->status == ISSL_HANDSHAKING_WRITE || session->status == ISSL_HANDSHAKING_READ) { // The handshake isn't finished, try to finish it. Handshake(session, user); if (session->status != ISSL_CLOSING) return 0; user->SetError("Handshake Failed"); return -1; } int ret = 0; if (session->status == ISSL_HANDSHAKEN) { ret = gnutls_record_send(session->sess, sendq.data(), sendq.length()); if (ret == (int)sendq.length()) { ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_WRITE); return 1; } else if (ret > 0) { sendq = sendq.substr(ret); ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE); return 0; } else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED) { ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE); return 0; } else if (ret == 0) { CloseSession(session); user->SetError("SSL Connection closed"); return -1; } else // (ret < 0) { user->SetError(gnutls_strerror(ret)); CloseSession(session); return -1; } } return 0; } bool Handshake(issl_session* session, StreamSocket* user) { 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->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE); } else { // gnutls_handshake() wants to write() again. session->status = ISSL_HANDSHAKING_WRITE; ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE); } } else { CloseSession(session); session->status = ISSL_CLOSING; } return false; } else { // Change the seesion state session->status = ISSL_HANDSHAKEN; VerifyCertificate(session,user); // Finish writing, if any left ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE | FD_ADD_TRIAL_WRITE); return true; } } 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))) { 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()); } } } void CloseSession(issl_session* session) { if(session->sess) { gnutls_bye(session->sess, GNUTLS_SHUT_WR); gnutls_deinit(session->sess); } session->sess = NULL; session->status = ISSL_NONE; } void VerifyCertificate(issl_session* session, Extensible* user) { if (!session->sess || !user) return; Module* sslinfo = ServerInstance->Modules->Find("m_sslinfo.so"); if (!sslinfo) 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; /* 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)); goto info_done; } 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"; goto info_done; } ret = gnutls_x509_crt_init(&cert); if (ret < 0) { certinfo->error = gnutls_strerror(ret); goto info_done; } 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"; goto info_done_dealloc; } /* 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); goto info_done_dealloc; } 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"; } info_done_dealloc: gnutls_x509_crt_deinit(cert); info_done: BufferedSocketFingerprintSubmission(user, this, sslinfo, certinfo).Send(); } void OnEvent(Event* ev) { capHandler.HandleEvent(ev); } }; MODULE_INIT(ModuleSSLGnuTLS)