X-Git-Url: https://git.netwichtig.de/gitweb/?a=blobdiff_plain;f=src%2Fmodules%2Fextra%2Fm_ssl_openssl.cpp;h=8467cc6d416b5931efb721009aeca33611e7ea60;hb=b9e11915a976daaf790ebc763aff56e19fd49e0f;hp=7a8bdeeb00be52936a208dc2760a2a377516e878;hpb=f71e6bf9cb41811f18864f5d4eecb26e29d03f25;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 7a8bdeeb0..8467cc6d4 100644
--- a/src/modules/extra/m_ssl_openssl.cpp
+++ b/src/modules/extra/m_ssl_openssl.cpp
@@ -21,39 +21,43 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
- /* HACK: This prevents OpenSSL on OS X 10.7 and later from spewing deprecation
-  * warnings for every single function call. As far as I (SaberUK) know, Apple
-  * have no plans to remove OpenSSL so this warning just causes needless spam.
-  */
-#ifdef __APPLE__
-# define __AVAILABILITYMACROS__
-# define DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER
-#endif
 
 #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 <openssl/ssl.h>
 #include <openssl/err.h>
-#include "modules/ssl.h"
 
 #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")
-# undef MAX_DESCRIPTORS
-# define MAX_DESCRIPTORS 10000
+# pragma comment(lib, "ssleay32.lib")
+# pragma comment(lib, "libeay32.lib")
 #endif
 
-/* $CompileFlags: pkgconfversion("openssl","0.9.7") pkgconfincludes("openssl","/openssl/ssl.h","") -Wno-pedantic */
+/* $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()
 {
@@ -61,6 +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
 {
@@ -78,12 +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);
 		}
@@ -102,16 +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_NONE, NULL);
+			SSL_CTX_set_session_cache_mode(ctx, SSL_SESS_CACHE_OFF);
+			SSL_CTX_set_info_callback(ctx, StaticSSLInfoCallback);
 		}
 
 		~Context()
@@ -121,32 +144,85 @@ 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 SSL_new(ctx);
+			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);
+		}
+
+		void SetVerifyCert()
+		{
+			SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER | SSL_VERIFY_CLIENT_ONCE, OnVerify);
+		}
+
+		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;
 		}
 	};
 
@@ -173,6 +249,14 @@ 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<Profile*>(u);
@@ -180,12 +264,40 @@ 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");
@@ -205,6 +317,15 @@ 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.
 			 */
@@ -229,15 +350,62 @@ namespace OpenSSL
 				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());
 			}
+
+			clictx.SetVerifyCert();
+			if (tag->getBool("requestclientcert", true))
+				ctx.SetVerifyCert();
 		}
 
 		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.
@@ -257,19 +425,14 @@ class OpenSSLIOHook : public SSLIOHook
  private:
 	SSL* sess;
 	issl_status status;
-	const bool outbound;
 	bool data_to_write;
 	reference<OpenSSL::Profile> 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);
@@ -278,20 +441,19 @@ 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)
 		{
@@ -302,15 +464,13 @@ 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()
@@ -323,7 +483,6 @@ class OpenSSLIOHook : public SSLIOHook
 		sess = NULL;
 		certificate = NULL;
 		status = ISSL_NONE;
-		errno = EIO;
 	}
 
 	void VerifyCertificate()
@@ -358,8 +517,14 @@ 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))
 		{
@@ -378,20 +543,65 @@ 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<StreamSocket*>(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<OpenSSL::Profile>& sslprofile)
+	OpenSSLIOHook(IOHookProvider* hookprov, StreamSocket* sock, SSL* session, const reference<OpenSSL::Profile>& 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);
 	}
@@ -403,37 +613,32 @@ 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);
+				int mask = 0;
+				// Schedule a read if there is still data in the OpenSSL buffer
+				if (SSL_pending(sess) > 0)
+					mask |= FD_ADD_TRIAL_READ;
 				if (data_to_write)
-					SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_SINGLE_WRITE);
+					mask |= FD_WANT_POLL_READ | FD_WANT_SINGLE_WRITE;
+				if (mask != 0)
+					SocketEngine::ChangeEventMask(user, mask);
 				return 1;
 			}
 			else if (ret == 0)
@@ -443,7 +648,7 @@ 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);
 
@@ -464,43 +669,36 @@ class OpenSSLIOHook : public SSLIOHook
 				}
 			}
 		}
-
-		return 0;
 	}
 
-	int OnStreamSocketWrite(StreamSocket* user, std::string& buffer) CXX11_OVERRIDE
+	int OnStreamSocketWrite(StreamSocket* user, StreamSocket::SendQueue& sendq) 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
+		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;
 			}
@@ -509,7 +707,7 @@ class OpenSSLIOHook : public SSLIOHook
 				CloseSession();
 				return -1;
 			}
-			else if (ret < 0)
+			else // if (ret < 0)
 			{
 				int err = SSL_get_error(sess, ret);
 
@@ -530,23 +728,75 @@ 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)
+	void GetCiphersuite(std::string& out) const CXX11_OVERRIDE
 	{
-		if (sess)
-		{
-			std::string text = "*** You are connected using SSL cipher '" + std::string(SSL_get_cipher(sess)) + "'";
-			const std::string& fingerprint = certificate->fingerprint;
-			if (!fingerprint.empty())
-				text += " and your SSL fingerprint is " + fingerprint;
-
-			user->WriteNotice(text);
-		}
+		if (!IsHandshakeDone())
+			return;
+		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<OpenSSLIOHook*>(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<StreamSocket*>(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<StreamSocket*>(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<OpenSSL::Profile> profile;
@@ -566,12 +816,12 @@ 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);
 	}
 };
 
@@ -642,6 +892,14 @@ 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();
 	}
 
@@ -660,20 +918,13 @@ class ModuleSSLOpenSSL : public Module
 		}
 	}
 
-	void OnUserConnect(LocalUser* user) CXX11_OVERRIDE
-	{
-		IOHook* hook = user->eh.GetIOHook();
-		if (hook && hook->prov->creator == this)
-			static_cast<OpenSSLIOHook*>(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)
+			if ((user) && (user->eh.GetModHook(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.
@@ -682,6 +933,14 @@ class ModuleSSLOpenSSL : public Module
 		}
 	}
 
+	ModResult OnCheckReady(LocalUser* user) CXX11_OVERRIDE
+	{
+		const OpenSSLIOHook* const iohook = static_cast<OpenSSLIOHook*>(user->eh.GetModHook(this));
+		if ((iohook) && (!iohook->IsHandshakeDone()))
+			return MOD_RES_DENY;
+		return MOD_RES_PASSTHRU;
+	}
+
 	Version GetVersion() CXX11_OVERRIDE
 	{
 		return Version("Provides SSL support for clients", VF_VENDOR);