X-Git-Url: https://git.netwichtig.de/gitweb/?a=blobdiff_plain;f=src%2Fmodules%2Fextra%2Fm_ssl_openssl.cpp;h=c9ae14e11bad0b31547494d3b19cd9d3a052d199;hb=a71f34e4b17420cacc4a50c5af64fe15811a8148;hp=9ebc0de9d670031c5de34842d3c9dc8dc0fd9c62;hpb=8a28e50cd2f19c2766b3ed2278ad237ad788620a;p=user%2Fhenk%2Fcode%2Finspircd.git diff --git a/src/modules/extra/m_ssl_openssl.cpp b/src/modules/extra/m_ssl_openssl.cpp index 9ebc0de9d..c9ae14e11 100644 --- a/src/modules/extra/m_ssl_openssl.cpp +++ b/src/modules/extra/m_ssl_openssl.cpp @@ -31,25 +31,33 @@ # 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, "libcrypto.lib") -# pragma comment(lib, "libssl.lib") -# pragma comment(lib, "user32.lib") -# pragma comment(lib, "advapi32.lib") -# pragma comment(lib, "libgcc.lib") -# pragma comment(lib, "libmingwex.lib") -# pragma comment(lib, "gdi32.lib") +# 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") */ +#if ((OPENSSL_VERSION_NUMBER >= 0x10000000L) && (!(defined(OPENSSL_NO_ECDH)))) +// OpenSSL 0.9.8 includes some ECC support, but it's unfinished. Enable only for 1.0.0 and later. +#define INSPIRCD_OPENSSL_ENABLE_ECDH +#endif + enum issl_status { ISSL_NONE, ISSL_HANDSHAKING, ISSL_OPEN }; static bool SelfSigned = false; +static int exdataindex; char* get_error() { @@ -57,6 +65,7 @@ char* get_error() } static int OnVerify(int preverify_ok, X509_STORE_CTX* ctx); +static void StaticSSLInfoCallback(const SSL* ssl, int where, int rc); namespace OpenSSL { @@ -74,12 +83,13 @@ namespace OpenSSL public: DHParams(const std::string& filename) { - FILE* dhpfile = fopen(filename.c_str(), "r"); + BIO* dhpfile = BIO_new_file(filename.c_str(), "r"); if (dhpfile == NULL) - throw Exception("Couldn't open DH file " + filename + ": " + strerror(errno)); + throw Exception("Couldn't open DH file " + filename); + + dh = PEM_read_bio_DHparams(dhpfile, NULL, NULL, NULL); + BIO_free(dhpfile); - dh = PEM_read_DHparams(dhpfile, NULL, NULL, NULL); - fclose(dhpfile); if (!dh) throw Exception("Couldn't read DH params from file " + filename); } @@ -98,16 +108,33 @@ namespace OpenSSL class Context { SSL_CTX* const ctx; + long ctx_options; public: Context(SSL_CTX* context) : ctx(context) { - 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); + // 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 - const unsigned char session_id[] = "inspircd"; - SSL_CTX_set_session_id_context(ctx, session_id, sizeof(session_id) - 1); + ctx_options = SSL_CTX_set_options(ctx, opts); + + long mode = SSL_MODE_ENABLE_PARTIAL_WRITE | SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER; +#ifdef SSL_MODE_RELEASE_BUFFERS + mode |= SSL_MODE_RELEASE_BUFFERS; +#endif + SSL_CTX_set_mode(ctx, mode); + 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() @@ -117,32 +144,80 @@ namespace OpenSSL 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); } - SSL* CreateSession() + long GetDefaultContextOptions() const + { + return ctx_options; + } + + long SetRawContextOptions(long setoptions, long clearoptions) { - return SSL_new(ctx); + // 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* CreateServerSession() + { + SSL* sess = SSL_new(ctx); + SSL_set_accept_state(sess); // Act as server + return sess; + } + + SSL* CreateClientSession() + { + SSL* sess = SSL_new(ctx); + SSL_set_connect_state(sess); // Act as client + return sess; } }; @@ -169,6 +244,14 @@ namespace OpenSSL */ std::string lasterr; + /** True if renegotiations are allowed, false if not + */ + const bool allowrenego; + + /** Rough max size of records to send + */ + const unsigned int outrecsize; + static int error_callback(const char* str, size_t len, void* u) { Profile* profile = reinterpret_cast(u); @@ -176,12 +259,40 @@ namespace OpenSSL 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", false)) // Disable compression by default + setoptions |= SSL_OP_NO_COMPRESSION; +#endif + if (!tag->getBool("sslv3", false)) // Disable SSLv3 by default + 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")) // Disallow by default + , outrecsize(tag->getInt("outrecsize", 2048, 512, 16384)) { if ((!ctx.SetDH(dh)) || (!clictx.SetDH(dh))) throw Exception("Couldn't set DH parameters"); @@ -201,6 +312,15 @@ namespace OpenSSL } } +#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. */ @@ -228,12 +348,55 @@ namespace OpenSSL } const std::string& GetName() const { return name; } - SSL* CreateServerSession() { return ctx.CreateSession(); } - SSL* CreateClientSession() { return clictx.CreateSession(); } + SSL* CreateServerSession() { return ctx.CreateServerSession(); } + SSL* CreateClientSession() { return clictx.CreateClientSession(); } const EVP_MD* GetDigest() { return digest; } + bool AllowRenegotiation() const { return allowrenego; } + unsigned int GetOutgoingRecordSize() const { return outrecsize; } }; + + namespace BIOMethod + { + static int create(BIO* bio) + { + bio->init = 1; + return 1; + } + + static int destroy(BIO* bio) + { + // XXX: Dummy function to avoid a memory leak in OpenSSL. + // The memory leak happens in BIO_free() (bio_lib.c) when the destroy func of the BIO is NULL. + // This is fixed in OpenSSL but some distros still ship the unpatched version hence we provide this workaround. + return 1; + } + + static long ctrl(BIO* bio, int cmd, long num, void* ptr) + { + if (cmd == BIO_CTRL_FLUSH) + return 1; + return 0; + } + + static int read(BIO* bio, char* buf, int len); + static int write(BIO* bio, const char* buf, int len); + } } +static BIO_METHOD biomethods = +{ + (100 | BIO_TYPE_SOURCE_SINK), + "inspircd", + OpenSSL::BIOMethod::write, + OpenSSL::BIOMethod::read, + NULL, // puts + NULL, // gets + OpenSSL::BIOMethod::ctrl, + OpenSSL::BIOMethod::create, + OpenSSL::BIOMethod::destroy, // destroy, does nothing, see function body for more info + NULL // callback_ctrl +}; + static int OnVerify(int preverify_ok, X509_STORE_CTX *ctx) { /* XXX: This will allow self signed certificates. @@ -253,19 +416,14 @@ class OpenSSLIOHook : public SSLIOHook private: SSL* sess; issl_status status; - const bool outbound; bool data_to_write; reference profile; - bool Handshake(StreamSocket* user) + // Returns 1 if handshake succeeded, 0 if it is still in progress, -1 if it failed + int Handshake(StreamSocket* user) { - int ret; - - if (outbound) - ret = SSL_connect(sess); - else - ret = SSL_accept(sess); - + ERR_clear_error(); + int ret = SSL_do_handshake(sess); if (ret < 0) { int err = SSL_get_error(sess, ret); @@ -274,20 +432,19 @@ class OpenSSLIOHook : public SSLIOHook { SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE); this->status = ISSL_HANDSHAKING; - return true; + return 0; } else if (err == SSL_ERROR_WANT_WRITE) { SocketEngine::ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE); this->status = ISSL_HANDSHAKING; - return true; + return 0; } else { CloseSession(); + return -1; } - - return false; } else if (ret > 0) { @@ -298,15 +455,13 @@ class OpenSSLIOHook : public SSLIOHook SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE | FD_ADD_TRIAL_WRITE); - return true; + return 1; } else if (ret == 0) { CloseSession(); - return true; } - - return true; + return -1; } void CloseSession() @@ -319,7 +474,6 @@ class OpenSSLIOHook : public SSLIOHook sess = NULL; certificate = NULL; status = ISSL_NONE; - errno = EIO; } void VerifyCertificate() @@ -354,8 +508,14 @@ class OpenSSLIOHook : public SSLIOHook 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)) { @@ -374,20 +534,65 @@ class OpenSSLIOHook : public SSLIOHook X509_free(cert); } + 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; + BIO* bio = SSL_get_rbio(sess); + EventHandler* eh = static_cast(bio->ptr); + SocketEngine::Shutdown(eh, 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; + } + + // Returns 1 if application I/O should proceed, 0 if it must wait for the underlying protocol to progress, -1 on fatal error + int PrepareIO(StreamSocket* sock) + { + if (status == ISSL_OPEN) + return 1; + else if (status == ISSL_HANDSHAKING) + { + // The handshake isn't finished, try to finish it + return Handshake(sock); + } + + CloseSession(); + return -1; + } + + // 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) + OpenSSLIOHook(IOHookProvider* hookprov, StreamSocket* sock, 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())); + // Create BIO instance and store a pointer to the socket in it which will be used by the read and write functions + BIO* bio = BIO_new(&biomethods); + bio->ptr = sock; + SSL_set_bio(sess, bio, bio); + SSL_set_ex_data(sess, exdataindex, this); sock->AddIOHook(this); Handshake(sock); } @@ -399,32 +604,21 @@ class OpenSSLIOHook : public SSLIOHook 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; - } - } + // Finish handshake if needed + int prepret = PrepareIO(user); + if (prepret <= 0) + return prepret; // 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); + if (!CheckRenego(user)) + return -1; + if (ret > 0) { recvq.append(buffer, ret); @@ -439,7 +633,7 @@ class OpenSSLIOHook : public SSLIOHook user->SetError("Connection closed"); return -1; } - else if (ret < 0) + else // if (ret < 0) { int err = SSL_get_error(sess, ret); @@ -460,43 +654,37 @@ class OpenSSLIOHook : public SSLIOHook } } } - - return 0; } - int OnStreamSocketWrite(StreamSocket* user, std::string& buffer) CXX11_OVERRIDE + int OnStreamSocketWrite(StreamSocket* user) CXX11_OVERRIDE { - if (!sess) - { - CloseSession(); - return -1; - } + // Finish handshake if needed + int prepret = PrepareIO(user); + if (prepret <= 0) + return prepret; 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) + // Session is ready for transferring application data + StreamSocket::SendQueue& sendq = user->GetSendQ(); + while (!sendq.empty()) { + ERR_clear_error(); + FlattenSendQueue(sendq, profile->GetOutgoingRecordSize()); + const StreamSocket::SendQueue::Element& buffer = sendq.front(); int ret = SSL_write(sess, buffer.data(), buffer.size()); + + if (!CheckRenego(user)) + return -1; + if (ret == (int)buffer.length()) { - data_to_write = false; - SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE); - return 1; + // Wrote entire record, continue sending + sendq.pop_front(); } else if (ret > 0) { - buffer = buffer.substr(ret); + sendq.erase_front(ret); SocketEngine::ChangeEventMask(user, FD_WANT_SINGLE_WRITE); return 0; } @@ -505,7 +693,7 @@ class OpenSSLIOHook : public SSLIOHook CloseSession(); return -1; } - else if (ret < 0) + else // if (ret < 0) { int err = SSL_get_error(sess, ret); @@ -526,23 +714,88 @@ class OpenSSLIOHook : public SSLIOHook } } } - return 0; + + data_to_write = false; + SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE); + return 1; } void TellCiphersAndFingerprint(LocalUser* user) { if (sess) { - std::string text = "*** You are connected using SSL cipher '" + std::string(SSL_get_cipher(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 fingerprint is " + fingerprint; + 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)); + } + + bool IsHandshakeDone() const { return (status == ISSL_OPEN); } }; +static void StaticSSLInfoCallback(const SSL* ssl, int where, int rc) +{ + OpenSSLIOHook* hook = static_cast(SSL_get_ex_data(ssl, exdataindex)); + hook->SSLInfoCallback(where, rc); +} + +static int OpenSSL::BIOMethod::write(BIO* bio, const char* buffer, int size) +{ + BIO_clear_retry_flags(bio); + + StreamSocket* sock = static_cast(bio->ptr); + if (sock->GetEventMask() & FD_WRITE_WILL_BLOCK) + { + // Writes blocked earlier, don't retry syscall + BIO_set_retry_write(bio); + return -1; + } + + int ret = SocketEngine::Send(sock, buffer, size, 0); + if ((ret < size) && ((ret > 0) || (SocketEngine::IgnoreError()))) + { + // Blocked, set retry flag for OpenSSL + SocketEngine::ChangeEventMask(sock, FD_WRITE_WILL_BLOCK); + BIO_set_retry_write(bio); + } + + return ret; +} + +static int OpenSSL::BIOMethod::read(BIO* bio, char* buffer, int size) +{ + BIO_clear_retry_flags(bio); + + StreamSocket* sock = static_cast(bio->ptr); + if (sock->GetEventMask() & FD_READ_WILL_BLOCK) + { + // Reads blocked earlier, don't retry syscall + BIO_set_retry_read(bio); + return -1; + } + + int ret = SocketEngine::Recv(sock, buffer, size, 0); + if ((ret < size) && ((ret > 0) || (SocketEngine::IgnoreError()))) + { + // Blocked, set retry flag for OpenSSL + SocketEngine::ChangeEventMask(sock, FD_READ_WILL_BLOCK); + BIO_set_retry_read(bio); + } + + return ret; +} + class OpenSSLIOHookProvider : public refcountbase, public IOHookProvider { reference profile; @@ -562,12 +815,12 @@ class OpenSSLIOHookProvider : public refcountbase, public IOHookProvider void OnAccept(StreamSocket* sock, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server) CXX11_OVERRIDE { - new OpenSSLIOHook(this, sock, false, profile->CreateServerSession(), profile); + new OpenSSLIOHook(this, sock, profile->CreateServerSession(), profile); } void OnConnect(StreamSocket* sock) CXX11_OVERRIDE { - new OpenSSLIOHook(this, sock, true, profile->CreateClientSession(), profile); + new OpenSSLIOHook(this, sock, profile->CreateClientSession(), profile); } }; @@ -638,6 +891,14 @@ class ModuleSSLOpenSSL : public Module void init() CXX11_OVERRIDE { + ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "OpenSSL lib version \"%s\" module was compiled for \"" OPENSSL_VERSION_TEXT "\"", SSLeay_version(SSLEAY_VERSION)); + + // 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(); } @@ -678,6 +939,18 @@ class ModuleSSLOpenSSL : public Module } } + ModResult OnCheckReady(LocalUser* user) CXX11_OVERRIDE + { + if ((user->eh.GetIOHook()) && (user->eh.GetIOHook()->prov->creator == this)) + { + OpenSSLIOHook* iohook = static_cast(user->eh.GetIOHook()); + if (!iohook->IsHandshakeDone()) + return MOD_RES_DENY; + } + + return MOD_RES_PASSTHRU; + } + Version GetVersion() CXX11_OVERRIDE { return Version("Provides SSL support for clients", VF_VENDOR);