/* * InspIRCd -- Internet Relay Chat Daemon * * Copyright (C) 2009-2010 Daniel De Graaf * Copyright (C) 2008 Pippijn van Steenhoven * Copyright (C) 2006-2008 Craig Edwards * Copyright (C) 2008 Thomas Stagner * Copyright (C) 2007 Dennis Friis * Copyright (C) 2006 Oliver Lupton * * This file is part of InspIRCd. InspIRCd is free software: you can * redistribute it and/or modify it under the terms of the GNU General Public * License as published by the Free Software Foundation, version 2. * * This program is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more * details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #include "inspircd.h" #include "iohook.h" #include "modules/ssl.h" // Ignore OpenSSL deprecation warnings on OS X Lion and newer. #if defined __APPLE__ # pragma GCC diagnostic ignored "-Wdeprecated-declarations" #endif // Fix warnings about the use of `long long` on C++03. #if defined __clang__ # pragma clang diagnostic ignored "-Wc++11-long-long" #elif defined __GNUC__ # pragma GCC diagnostic ignored "-Wlong-long" #endif #include #include #ifdef _WIN32 # pragma comment(lib, "ssleay32.lib") # pragma comment(lib, "libeay32.lib") #endif /* $CompileFlags: pkgconfversion("openssl","0.9.7") pkgconfincludes("openssl","/openssl/ssl.h","") */ /* $LinkerFlags: rpath("pkg-config --libs openssl") pkgconflibs("openssl","/libssl.so","-lssl -lcrypto") */ enum issl_status { ISSL_NONE, ISSL_HANDSHAKING, ISSL_OPEN }; static bool SelfSigned = false; static int exdataindex; char* get_error() { return ERR_error_string(ERR_get_error(), NULL); } static int OnVerify(int preverify_ok, X509_STORE_CTX* ctx); static void StaticSSLInfoCallback(const SSL* ssl, int where, int rc); namespace OpenSSL { class Exception : public ModuleException { public: Exception(const std::string& reason) : ModuleException(reason) { } }; class DHParams { DH* dh; public: DHParams(const std::string& filename) { BIO* dhpfile = BIO_new_file(filename.c_str(), "r"); if (dhpfile == NULL) throw Exception("Couldn't open DH file " + filename); dh = PEM_read_bio_DHparams(dhpfile, NULL, NULL, NULL); BIO_free(dhpfile); if (!dh) throw Exception("Couldn't read DH params from file " + filename); } ~DHParams() { DH_free(dh); } DH* get() { return dh; } }; class Context { SSL_CTX* const ctx; long ctx_options; public: Context(SSL_CTX* context) : ctx(context) { // Sane default options for OpenSSL see https://www.openssl.org/docs/ssl/SSL_CTX_set_options.html // and when choosing a cipher, use the server's preferences instead of the client preferences. long opts = SSL_OP_NO_SSLv2 | SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION | SSL_OP_CIPHER_SERVER_PREFERENCE | SSL_OP_SINGLE_DH_USE; // Only turn options on if they exist #ifdef SSL_OP_SINGLE_ECDH_USE opts |= SSL_OP_SINGLE_ECDH_USE; #endif #ifdef SSL_OP_NO_TICKET opts |= SSL_OP_NO_TICKET; #endif ctx_options = SSL_CTX_set_options(ctx, opts); SSL_CTX_set_mode(ctx, SSL_MODE_ENABLE_PARTIAL_WRITE | SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER); SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER | SSL_VERIFY_CLIENT_ONCE, OnVerify); SSL_CTX_set_session_cache_mode(ctx, SSL_SESS_CACHE_OFF); SSL_CTX_set_info_callback(ctx, StaticSSLInfoCallback); } ~Context() { SSL_CTX_free(ctx); } bool SetDH(DHParams& dh) { ERR_clear_error(); return (SSL_CTX_set_tmp_dh(ctx, dh.get()) >= 0); } #ifdef INSPIRCD_OPENSSL_ENABLE_ECDH void SetECDH(const std::string& curvename) { int nid = OBJ_sn2nid(curvename.c_str()); if (nid == 0) throw Exception("Unknown curve: " + curvename); EC_KEY* eckey = EC_KEY_new_by_curve_name(nid); if (!eckey) throw Exception("Unable to create EC key object"); ERR_clear_error(); bool ret = (SSL_CTX_set_tmp_ecdh(ctx, eckey) >= 0); EC_KEY_free(eckey); if (!ret) throw Exception("Couldn't set ECDH parameters"); } #endif bool SetCiphers(const std::string& ciphers) { ERR_clear_error(); return SSL_CTX_set_cipher_list(ctx, ciphers.c_str()); } bool SetCerts(const std::string& filename) { ERR_clear_error(); return SSL_CTX_use_certificate_chain_file(ctx, filename.c_str()); } bool SetPrivateKey(const std::string& filename) { ERR_clear_error(); return SSL_CTX_use_PrivateKey_file(ctx, filename.c_str(), SSL_FILETYPE_PEM); } bool SetCA(const std::string& filename) { ERR_clear_error(); return SSL_CTX_load_verify_locations(ctx, filename.c_str(), 0); } long GetDefaultContextOptions() const { return ctx_options; } long SetRawContextOptions(long setoptions, long clearoptions) { // Clear everything SSL_CTX_clear_options(ctx, SSL_CTX_get_options(ctx)); // Set the default options and what is in the conf SSL_CTX_set_options(ctx, ctx_options | setoptions); return SSL_CTX_clear_options(ctx, clearoptions); } SSL* CreateSession() { return SSL_new(ctx); } }; class Profile : public refcountbase { /** Name of this profile */ const std::string name; /** DH parameters in use */ DHParams dh; /** OpenSSL makes us have two contexts, one for servers and one for clients */ Context ctx; Context clictx; /** Digest to use when generating fingerprints */ const EVP_MD* digest; /** Last error, set by error_callback() */ std::string lasterr; /** True if renegotiations are allowed, false if not */ const bool allowrenego; static int error_callback(const char* str, size_t len, void* u) { Profile* profile = reinterpret_cast(u); profile->lasterr = std::string(str, len - 1); return 0; } /** Set raw OpenSSL context (SSL_CTX) options from a config tag * @param ctxname Name of the context, client or server * @param tag Config tag defining this profile * @param context Context object to manipulate */ void SetContextOptions(const std::string& ctxname, ConfigTag* tag, Context& context) { long setoptions = tag->getInt(ctxname + "setoptions"); long clearoptions = tag->getInt(ctxname + "clearoptions"); #ifdef SSL_OP_NO_COMPRESSION if (!tag->getBool("compression", true)) setoptions |= SSL_OP_NO_COMPRESSION; #endif if (!tag->getBool("sslv3", true)) setoptions |= SSL_OP_NO_SSLv3; if (!tag->getBool("tlsv1", true)) setoptions |= SSL_OP_NO_TLSv1; if (!setoptions && !clearoptions) return; // Nothing to do ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Setting %s %s context options, default: %ld set: %ld clear: %ld", name.c_str(), ctxname.c_str(), ctx.GetDefaultContextOptions(), setoptions, clearoptions); long final = context.SetRawContextOptions(setoptions, clearoptions); ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "%s %s context options: %ld", name.c_str(), ctxname.c_str(), final); } public: Profile(const std::string& profilename, ConfigTag* tag) : name(profilename) , dh(ServerInstance->Config->Paths.PrependConfig(tag->getString("dhfile", "dh.pem"))) , ctx(SSL_CTX_new(SSLv23_server_method())) , clictx(SSL_CTX_new(SSLv23_client_method())) , allowrenego(tag->getBool("renegotiation", true)) { if ((!ctx.SetDH(dh)) || (!clictx.SetDH(dh))) throw Exception("Couldn't set DH parameters"); std::string hash = tag->getString("hash", "md5"); digest = EVP_get_digestbyname(hash.c_str()); if (digest == NULL) throw Exception("Unknown hash type " + hash); std::string ciphers = tag->getString("ciphers"); if (!ciphers.empty()) { if ((!ctx.SetCiphers(ciphers)) || (!clictx.SetCiphers(ciphers))) { ERR_print_errors_cb(error_callback, this); throw Exception("Can't set cipher list to \"" + ciphers + "\" " + lasterr); } } #ifdef INSPIRCD_OPENSSL_ENABLE_ECDH std::string curvename = tag->getString("ecdhcurve", "prime256v1"); if (!curvename.empty()) ctx.SetECDH(curvename); #endif SetContextOptions("server", tag, ctx); SetContextOptions("client", tag, clictx); /* Load our keys and certificates * NOTE: OpenSSL's error logging API sucks, don't blame us for this clusterfuck. */ std::string filename = ServerInstance->Config->Paths.PrependConfig(tag->getString("certfile", "cert.pem")); if ((!ctx.SetCerts(filename)) || (!clictx.SetCerts(filename))) { ERR_print_errors_cb(error_callback, this); throw Exception("Can't read certificate file: " + lasterr); } filename = ServerInstance->Config->Paths.PrependConfig(tag->getString("keyfile", "key.pem")); if ((!ctx.SetPrivateKey(filename)) || (!clictx.SetPrivateKey(filename))) { ERR_print_errors_cb(error_callback, this); throw Exception("Can't read key file: " + lasterr); } // Load the CAs we trust filename = ServerInstance->Config->Paths.PrependConfig(tag->getString("cafile", "ca.pem")); if ((!ctx.SetCA(filename)) || (!clictx.SetCA(filename))) { ERR_print_errors_cb(error_callback, this); ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Can't read CA list from %s. This is only a problem if you want to verify client certificates, otherwise it's safe to ignore this message. Error: %s", filename.c_str(), lasterr.c_str()); } } const std::string& GetName() const { return name; } SSL* CreateServerSession() { return ctx.CreateSession(); } SSL* CreateClientSession() { return clictx.CreateSession(); } const EVP_MD* GetDigest() { return digest; } bool AllowRenegotiation() const { return allowrenego; } }; } static int OnVerify(int preverify_ok, X509_STORE_CTX *ctx) { /* XXX: This will allow self signed certificates. * In the future if we want an option to not allow this, * we can just return preverify_ok here, and openssl * will boot off self-signed and invalid peer certs. */ int ve = X509_STORE_CTX_get_error(ctx); SelfSigned = (ve == X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT); return 1; } class OpenSSLIOHook : public SSLIOHook { private: SSL* sess; issl_status status; const bool outbound; bool data_to_write; reference profile; bool Handshake(StreamSocket* user) { int ret; ERR_clear_error(); if (outbound) ret = SSL_connect(sess); else ret = SSL_accept(sess); if (ret < 0) { int err = SSL_get_error(sess, ret); if (err == SSL_ERROR_WANT_READ) { SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE); this->status = ISSL_HANDSHAKING; return true; } else if (err == SSL_ERROR_WANT_WRITE) { SocketEngine::ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE); this->status = ISSL_HANDSHAKING; return true; } else { CloseSession(); } return false; } else if (ret > 0) { // Handshake complete. VerifyCertificate(); status = ISSL_OPEN; SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE | FD_ADD_TRIAL_WRITE); return true; } else if (ret == 0) { CloseSession(); } return false; } void CloseSession() { if (sess) { SSL_shutdown(sess); SSL_free(sess); } sess = NULL; certificate = NULL; status = ISSL_NONE; } void VerifyCertificate() { X509* cert; ssl_cert* certinfo = new ssl_cert; this->certificate = certinfo; unsigned int n; unsigned char md[EVP_MAX_MD_SIZE]; cert = SSL_get_peer_certificate(sess); if (!cert) { certinfo->error = "Could not get peer certificate: "+std::string(get_error()); return; } certinfo->invalid = (SSL_get_verify_result(sess) != X509_V_OK); if (!SelfSigned) { certinfo->unknownsigner = false; certinfo->trusted = true; } else { certinfo->unknownsigner = true; certinfo->trusted = false; } char buf[512]; X509_NAME_oneline(X509_get_subject_name(cert), buf, sizeof(buf)); certinfo->dn = buf; // Make sure there are no chars in the string that we consider invalid if (certinfo->dn.find_first_of("\r\n") != std::string::npos) certinfo->dn.clear(); X509_NAME_oneline(X509_get_issuer_name(cert), buf, sizeof(buf)); certinfo->issuer = buf; if (certinfo->issuer.find_first_of("\r\n") != std::string::npos) certinfo->issuer.clear(); if (!X509_digest(cert, profile->GetDigest(), md, &n)) { certinfo->error = "Out of memory generating fingerprint"; } else { certinfo->fingerprint = BinToHex(md, n); } if ((ASN1_UTCTIME_cmp_time_t(X509_get_notAfter(cert), ServerInstance->Time()) == -1) || (ASN1_UTCTIME_cmp_time_t(X509_get_notBefore(cert), ServerInstance->Time()) == 0)) { certinfo->error = "Not activated, or expired certificate"; } X509_free(cert); } #ifdef INSPIRCD_OPENSSL_ENABLE_RENEGO_DETECTION void SSLInfoCallback(int where, int rc) { if ((where & SSL_CB_HANDSHAKE_START) && (status == ISSL_OPEN)) { if (profile->AllowRenegotiation()) return; // The other side is trying to renegotiate, kill the connection and change status // to ISSL_NONE so CheckRenego() closes the session status = ISSL_NONE; SocketEngine::Shutdown(SSL_get_fd(sess), 2); } } bool CheckRenego(StreamSocket* sock) { if (status != ISSL_NONE) return true; ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Session %p killed, attempted to renegotiate", (void*)sess); CloseSession(); sock->SetError("Renegotiation is not allowed"); return false; } #endif // Calls our private SSLInfoCallback() friend void StaticSSLInfoCallback(const SSL* ssl, int where, int rc); public: OpenSSLIOHook(IOHookProvider* hookprov, StreamSocket* sock, bool is_outbound, SSL* session, const reference& sslprofile) : SSLIOHook(hookprov) , sess(session) , status(ISSL_NONE) , outbound(is_outbound) , data_to_write(false) , profile(sslprofile) { if (sess == NULL) return; if (SSL_set_fd(sess, sock->GetFd()) == 0) throw ModuleException("Can't set fd with SSL_set_fd: " + ConvToStr(sock->GetFd())); SSL_set_ex_data(sess, exdataindex, this); sock->AddIOHook(this); Handshake(sock); } void OnStreamSocketClose(StreamSocket* user) CXX11_OVERRIDE { CloseSession(); } int OnStreamSocketRead(StreamSocket* user, std::string& recvq) CXX11_OVERRIDE { if (!sess) { CloseSession(); return -1; } if (status == ISSL_HANDSHAKING) { // The handshake isn't finished and it wants to read, try to finish it. if (!Handshake(user)) { // Couldn't resume handshake. if (status == ISSL_NONE) return -1; return 0; } } // If we resumed the handshake then this->status will be ISSL_OPEN if (status == ISSL_OPEN) { ERR_clear_error(); char* buffer = ServerInstance->GetReadBuffer(); size_t bufsiz = ServerInstance->Config->NetBufferSize; int ret = SSL_read(sess, buffer, bufsiz); #ifdef INSPIRCD_OPENSSL_ENABLE_RENEGO_DETECTION if (!CheckRenego(user)) return -1; #endif if (ret > 0) { recvq.append(buffer, ret); if (data_to_write) SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_SINGLE_WRITE); return 1; } else if (ret == 0) { // Client closed connection. CloseSession(); user->SetError("Connection closed"); return -1; } else if (ret < 0) { int err = SSL_get_error(sess, ret); if (err == SSL_ERROR_WANT_READ) { SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ); return 0; } else if (err == SSL_ERROR_WANT_WRITE) { SocketEngine::ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE); return 0; } else { CloseSession(); return -1; } } } return 0; } int OnStreamSocketWrite(StreamSocket* user, std::string& buffer) CXX11_OVERRIDE { if (!sess) { CloseSession(); return -1; } data_to_write = true; if (status == ISSL_HANDSHAKING) { if (!Handshake(user)) { // Couldn't resume handshake. if (status == ISSL_NONE) return -1; return 0; } } if (status == ISSL_OPEN) { ERR_clear_error(); int ret = SSL_write(sess, buffer.data(), buffer.size()); #ifdef INSPIRCD_OPENSSL_ENABLE_RENEGO_DETECTION if (!CheckRenego(user)) return -1; #endif if (ret == (int)buffer.length()) { data_to_write = false; SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE); return 1; } else if (ret > 0) { buffer.erase(0, ret); SocketEngine::ChangeEventMask(user, FD_WANT_SINGLE_WRITE); return 0; } else if (ret == 0) { CloseSession(); return -1; } else if (ret < 0) { int err = SSL_get_error(sess, ret); if (err == SSL_ERROR_WANT_WRITE) { SocketEngine::ChangeEventMask(user, FD_WANT_SINGLE_WRITE); return 0; } else if (err == SSL_ERROR_WANT_READ) { SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ); return 0; } else { CloseSession(); return -1; } } } return 0; } void TellCiphersAndFingerprint(LocalUser* user) { if (sess) { std::string text = "*** You are connected using SSL cipher '"; GetCiphersuite(text); text += '\''; const std::string& fingerprint = certificate->fingerprint; if (!fingerprint.empty()) text += " and your SSL certificate fingerprint is " + fingerprint; user->WriteNotice(text); } } void GetCiphersuite(std::string& out) const { out.append(SSL_get_version(sess)).push_back('-'); out.append(SSL_get_cipher(sess)); } }; static void StaticSSLInfoCallback(const SSL* ssl, int where, int rc) { #ifdef INSPIRCD_OPENSSL_ENABLE_RENEGO_DETECTION OpenSSLIOHook* hook = static_cast(SSL_get_ex_data(ssl, exdataindex)); hook->SSLInfoCallback(where, rc); #endif } class OpenSSLIOHookProvider : public refcountbase, public IOHookProvider { reference profile; public: OpenSSLIOHookProvider(Module* mod, reference& prof) : IOHookProvider(mod, "ssl/" + prof->GetName(), IOHookProvider::IOH_SSL) , profile(prof) { ServerInstance->Modules->AddService(*this); } ~OpenSSLIOHookProvider() { ServerInstance->Modules->DelService(*this); } void OnAccept(StreamSocket* sock, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server) CXX11_OVERRIDE { new OpenSSLIOHook(this, sock, false, profile->CreateServerSession(), profile); } void OnConnect(StreamSocket* sock) CXX11_OVERRIDE { new OpenSSLIOHook(this, sock, true, profile->CreateClientSession(), profile); } }; class ModuleSSLOpenSSL : public Module { typedef std::vector > ProfileList; ProfileList profiles; void ReadProfiles() { ProfileList newprofiles; ConfigTagList tags = ServerInstance->Config->ConfTags("sslprofile"); if (tags.first == tags.second) { // Create a default profile named "openssl" const std::string defname = "openssl"; ConfigTag* tag = ServerInstance->Config->ConfValue(defname); ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "No tags found, using settings from the tag"); try { reference profile(new OpenSSL::Profile(defname, tag)); newprofiles.push_back(new OpenSSLIOHookProvider(this, profile)); } catch (OpenSSL::Exception& ex) { throw ModuleException("Error while initializing the default SSL profile - " + ex.GetReason()); } } for (ConfigIter i = tags.first; i != tags.second; ++i) { ConfigTag* tag = i->second; if (tag->getString("provider") != "openssl") continue; std::string name = tag->getString("name"); if (name.empty()) { ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Ignoring tag without name at " + tag->getTagLocation()); continue; } reference profile; try { profile = new OpenSSL::Profile(name, tag); } catch (CoreException& ex) { throw ModuleException("Error while initializing SSL profile \"" + name + "\" at " + tag->getTagLocation() + " - " + ex.GetReason()); } newprofiles.push_back(new OpenSSLIOHookProvider(this, profile)); } profiles.swap(newprofiles); } public: ModuleSSLOpenSSL() { // Initialize OpenSSL SSL_library_init(); SSL_load_error_strings(); } void init() CXX11_OVERRIDE { // Register application specific data char exdatastr[] = "inspircd"; exdataindex = SSL_get_ex_new_index(0, exdatastr, NULL, NULL, NULL); if (exdataindex < 0) throw ModuleException("Failed to register application specific data"); ReadProfiles(); } void OnModuleRehash(User* user, const std::string ¶m) CXX11_OVERRIDE { if (param != "ssl") return; try { ReadProfiles(); } catch (ModuleException& ex) { ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, ex.GetReason() + " Not applying settings."); } } void OnUserConnect(LocalUser* user) CXX11_OVERRIDE { IOHook* hook = user->eh.GetIOHook(); if (hook && hook->prov->creator == this) static_cast(hook)->TellCiphersAndFingerprint(user); } void OnCleanup(int target_type, void* item) CXX11_OVERRIDE { if (target_type == TYPE_USER) { LocalUser* user = IS_LOCAL((User*)item); if (user && user->eh.GetIOHook() && user->eh.GetIOHook()->prov->creator == 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"); } } } Version GetVersion() CXX11_OVERRIDE { return Version("Provides SSL support for clients", VF_VENDOR); } }; MODULE_INIT(ModuleSSLOpenSSL)