X-Git-Url: https://git.netwichtig.de/gitweb/?a=blobdiff_plain;f=src%2Fmodules%2Fextra%2Fm_ssl_gnutls.cpp;h=f8dc85659b1a82c927faef5d3f691c74ab968047;hb=2972f1ec3fbecb70f7ad7f4f605fb5b9264e8816;hp=228ceb99470264d7f163836f2e18b4bbf5607b6a;hpb=0035820e13a915a3bf1a440fcedf8ce25fe37a22;p=user%2Fhenk%2Fcode%2Finspircd.git

diff --git a/src/modules/extra/m_ssl_gnutls.cpp b/src/modules/extra/m_ssl_gnutls.cpp
index 228ceb994..f8dc85659 100644
--- a/src/modules/extra/m_ssl_gnutls.cpp
+++ b/src/modules/extra/m_ssl_gnutls.cpp
@@ -22,120 +22,70 @@
 
 
 #include "inspircd.h"
-#ifndef _WIN32
-#include <gcrypt.h>
+#include "modules/ssl.h"
+#include <memory>
+
+// Fix warnings about the use of commas at end of enumerator lists on C++03.
+#if defined __clang__
+# pragma clang diagnostic ignored "-Wc++11-extensions"
+#elif defined __GNUC__
+# pragma GCC diagnostic ignored "-pedantic"
 #endif
+
 #include <gnutls/gnutls.h>
 #include <gnutls/x509.h>
-#include "ssl.h"
-#include "m_cap.h"
-
-#ifdef _WIN32
-# pragma comment(lib, "libgnutls-28.lib")
-#endif
-
-/* $ModDesc: Provides SSL support for clients */
-/* $CompileFlags: pkgconfincludes("gnutls","/gnutls/gnutls.h","") exec("libgcrypt-config --cflags") */
-/* $LinkerFlags: rpath("pkg-config --libs gnutls") pkgconflibs("gnutls","/libgnutls.so","-lgnutls") exec("libgcrypt-config --libs") */
-/* $NoPedantic */
 
-#ifndef GNUTLS_VERSION_MAJOR
-#define GNUTLS_VERSION_MAJOR LIBGNUTLS_VERSION_MAJOR
-#define GNUTLS_VERSION_MINOR LIBGNUTLS_VERSION_MINOR
-#define GNUTLS_VERSION_PATCH LIBGNUTLS_VERSION_PATCH
+#ifndef GNUTLS_VERSION_NUMBER
+#define GNUTLS_VERSION_NUMBER LIBGNUTLS_VERSION_NUMBER
 #endif
 
-// These don't exist in older GnuTLS versions
-#if ((GNUTLS_VERSION_MAJOR > 2) || (GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR > 1) || (GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR == 1 && GNUTLS_VERSION_PATCH >= 7))
-#define GNUTLS_NEW_PRIO_API
-#endif
+// Check if the GnuTLS library is at least version major.minor.patch
+#define INSPIRCD_GNUTLS_HAS_VERSION(major, minor, patch) (GNUTLS_VERSION_NUMBER >= ((major << 16) | (minor << 8) | patch))
 
-#if(GNUTLS_VERSION_MAJOR < 2)
-typedef gnutls_certificate_credentials_t gnutls_certificate_credentials;
-typedef gnutls_dh_params_t gnutls_dh_params;
+#if INSPIRCD_GNUTLS_HAS_VERSION(2, 9, 8)
+#define GNUTLS_HAS_MAC_GET_ID
+#include <gnutls/crypto.h>
 #endif
 
-#if (defined(_WIN32) && (GNUTLS_VERSION_MAJOR > 2 || (GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR >= 12)))
+#if INSPIRCD_GNUTLS_HAS_VERSION(2, 12, 0)
 # define GNUTLS_HAS_RND
-# include <gnutls/crypto.h>
 #else
 # include <gcrypt.h>
 #endif
 
-enum issl_status { ISSL_NONE, ISSL_HANDSHAKING_READ, ISSL_HANDSHAKING_WRITE, ISSL_HANDSHAKEN, ISSL_CLOSING, ISSL_CLOSED };
-
-struct SSLConfig : public refcountbase
-{
-	gnutls_certificate_credentials_t x509_cred;
-	std::vector<gnutls_x509_crt_t> x509_certs;
-	gnutls_x509_privkey_t x509_key;
-	gnutls_dh_params_t dh_params;
-#ifdef GNUTLS_NEW_PRIO_API
-	gnutls_priority_t priority;
-#endif
-
-	SSLConfig()
-		: x509_cred(NULL)
-		, x509_key(NULL)
-		, dh_params(NULL)
-#ifdef GNUTLS_NEW_PRIO_API
-		, priority(NULL)
+#ifdef _WIN32
+# pragma comment(lib, "libgnutls-28.lib")
 #endif
-	{
-	}
-
-	~SSLConfig()
-	{
-		ServerInstance->Logs->Log("m_ssl_gnutls", DEBUG, "Destroying SSLConfig %p", (void*)this);
-
-		if (x509_cred)
-			gnutls_certificate_free_credentials(x509_cred);
 
-		for (unsigned int i = 0; i < x509_certs.size(); i++)
-			gnutls_x509_crt_deinit(x509_certs[i]);
+/* $CompileFlags: pkgconfincludes("gnutls","/gnutls/gnutls.h","") eval("print `libgcrypt-config --cflags | tr -d \r` if `pkg-config --modversion gnutls 2>/dev/null | tr -d \r` lt '2.12'") */
+/* $LinkerFlags: rpath("pkg-config --libs gnutls") pkgconflibs("gnutls","/libgnutls.so","-lgnutls") eval("print `libgcrypt-config --libs | tr -d \r` if `pkg-config --modversion gnutls 2>/dev/null | tr -d \r` lt '2.12'") */
 
-		if (x509_key)
-			gnutls_x509_privkey_deinit(x509_key);
-
-		if (dh_params)
-			gnutls_dh_params_deinit(dh_params);
-
-#ifdef GNUTLS_NEW_PRIO_API
-		if (priority)
-			gnutls_priority_deinit(priority);
+// These don't exist in older GnuTLS versions
+#if INSPIRCD_GNUTLS_HAS_VERSION(2, 1, 7)
+#define GNUTLS_NEW_PRIO_API
 #endif
-	}
-};
-
-static reference<SSLConfig> currconf;
 
-static SSLConfig* GetSessionConfig(gnutls_session_t session);
+#if (!INSPIRCD_GNUTLS_HAS_VERSION(2, 0, 0))
+typedef gnutls_certificate_credentials_t gnutls_certificate_credentials;
+typedef gnutls_dh_params_t gnutls_dh_params;
+#endif
 
-#if(GNUTLS_VERSION_MAJOR < 2 || ( GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR < 12 ) )
-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) {
+enum issl_status { ISSL_NONE, ISSL_HANDSHAKING, ISSL_HANDSHAKEN };
 
-	st->type = GNUTLS_CRT_X509;
+#if INSPIRCD_GNUTLS_HAS_VERSION(2, 12, 0)
+#define GNUTLS_NEW_CERT_CALLBACK_API
+typedef gnutls_retr2_st cert_cb_last_param_type;
 #else
-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_retr2_st * st) {
-	st->cert_type = GNUTLS_CRT_X509;
-	st->key_type = GNUTLS_PRIVKEY_X509;
+typedef gnutls_retr_st cert_cb_last_param_type;
 #endif
-	SSLConfig* conf = GetSessionConfig(session);
-	std::vector<gnutls_x509_crt_t>& x509_certs = conf->x509_certs;
-	st->ncerts = x509_certs.size();
-	st->cert.x509 = &x509_certs[0];
-	st->key.x509 = conf->x509_key;
-	st->deinit_all = 0;
 
-	return 0;
-}
+#if INSPIRCD_GNUTLS_HAS_VERSION(3, 3, 5)
+#define INSPIRCD_GNUTLS_HAS_RECV_PACKET
+#endif
 
 class RandGen : public HandlerBase2<void, char*, size_t>
 {
  public:
-	RandGen() {}
 	void Call(char* buffer, size_t len)
 	{
 #ifdef GNUTLS_HAS_RND
@@ -146,566 +96,812 @@ class RandGen : public HandlerBase2<void, char*, size_t>
 	}
 };
 
-/** Represents an SSL user's extra data
- */
-class issl_session
-{
-public:
-	StreamSocket* socket;
-	gnutls_session_t sess;
-	issl_status status;
-	reference<ssl_cert> cert;
-	reference<SSLConfig> config;
-
-	issl_session() : socket(NULL), sess(NULL), status(ISSL_NONE) {}
-};
-
-static SSLConfig* GetSessionConfig(gnutls_session_t sess)
+namespace GnuTLS
 {
-	issl_session* session = reinterpret_cast<issl_session*>(gnutls_transport_get_ptr(sess));
-	return session->config;
-}
+	class Init
+	{
+	 public:
+		Init() { gnutls_global_init(); }
+		~Init() { gnutls_global_deinit(); }
+	};
 
-class CommandStartTLS : public SplitCommand
-{
- public:
-	bool enabled;
-	CommandStartTLS (Module* mod) : SplitCommand(mod, "STARTTLS")
+	class Exception : public ModuleException
 	{
-		enabled = true;
-		works_before_reg = true;
-	}
+	 public:
+		Exception(const std::string& reason)
+			: ModuleException(reason) { }
+	};
 
-	CmdResult HandleLocal(const std::vector<std::string> &parameters, LocalUser *user)
+	void ThrowOnError(int errcode, const char* msg)
 	{
-		if (!enabled)
+		if (errcode < 0)
 		{
-			user->WriteNumeric(691, "%s :STARTTLS is not enabled", user->nick.c_str());
-			return CMD_FAILURE;
+			std::string reason = msg;
+			reason.append(" :").append(gnutls_strerror(errcode));
+			throw Exception(reason);
 		}
+	}
 
-		if (user->registered == REG_ALL)
-		{
-			user->WriteNumeric(691, "%s :STARTTLS is not permitted after client registration is complete", user->nick.c_str());
-		}
-		else
+	/** Used to create a gnutls_datum_t* from a std::string
+	 */
+	class Datum
+	{
+		gnutls_datum_t datum;
+
+	 public:
+		Datum(const std::string& dat)
 		{
-			if (!user->eh.GetIOHook())
-			{
-				user->WriteNumeric(670, "%s :STARTTLS successful, go ahead with TLS handshake", user->nick.c_str());
-				/* We need to flush the write buffer prior to adding the IOHook,
-				 * otherwise we'll be sending this line inside the SSL session - which
-				 * won't start its handshake until the client gets this line. Currently,
-				 * we assume the write will not block here; this is usually safe, as
-				 * STARTTLS is sent very early on in the registration phase, where the
-				 * user hasn't built up much sendq. Handling a blocked write here would
-				 * be very annoying.
-				 */
-				user->eh.DoWrite();
-				user->eh.AddIOHook(creator);
-				creator->OnStreamSocketAccept(&user->eh, NULL, NULL);
-			}
-			else
-				user->WriteNumeric(691, "%s :STARTTLS failure", user->nick.c_str());
+			datum.data = (unsigned char*)dat.data();
+			datum.size = static_cast<unsigned int>(dat.length());
 		}
 
-		return CMD_FAILURE;
-	}
-};
-
-class ModuleSSLGnuTLS : public Module
-{
-	issl_session* sessions;
+		const gnutls_datum_t* get() const { return &datum; }
+	};
 
-	gnutls_digest_algorithm_t hash;
-
-	std::string sslports;
-	int dh_bits;
+	class Hash
+	{
+		gnutls_digest_algorithm_t hash;
 
-	RandGen randhandler;
-	CommandStartTLS starttls;
+	 public:
+		// Nothing to deallocate, constructor may throw freely
+		Hash(const std::string& hashname)
+		{
+			// As older versions of gnutls can't do this, let's disable it where needed.
+#ifdef GNUTLS_HAS_MAC_GET_ID
+			// As gnutls_digest_algorithm_t and gnutls_mac_algorithm_t are mapped 1:1, we can do this
+			// There is no gnutls_dig_get_id() at the moment, but it may come later
+			hash = (gnutls_digest_algorithm_t)gnutls_mac_get_id(hashname.c_str());
+			if (hash == GNUTLS_DIG_UNKNOWN)
+				throw Exception("Unknown hash type " + hashname);
+
+			// Check if the user is giving us something that is a valid MAC but not digest
+			gnutls_hash_hd_t is_digest;
+			if (gnutls_hash_init(&is_digest, hash) < 0)
+				throw Exception("Unknown hash type " + hashname);
+			gnutls_hash_deinit(is_digest, NULL);
+#else
+			if (hashname == "md5")
+				hash = GNUTLS_DIG_MD5;
+			else if (hashname == "sha1")
+				hash = GNUTLS_DIG_SHA1;
+#ifdef INSPIRCD_GNUTLS_ENABLE_SHA256_FINGERPRINT
+			else if (hashname == "sha256")
+				hash = GNUTLS_DIG_SHA256;
+#endif
+			else
+				throw Exception("Unknown hash type " + hashname);
+#endif
+		}
 
-	GenericCap capHandler;
-	ServiceProvider iohook;
+		gnutls_digest_algorithm_t get() const { return hash; }
+	};
 
-	inline static const char* UnknownIfNULL(const char* str)
+	class DHParams
 	{
-		return str ? str : "UNKNOWN";
-	}
+		gnutls_dh_params_t dh_params;
 
-	static ssize_t gnutls_pull_wrapper(gnutls_transport_ptr_t session_wrap, void* buffer, size_t size)
-	{
-		issl_session* session = reinterpret_cast<issl_session*>(session_wrap);
-		if (session->socket->GetEventMask() & FD_READ_WILL_BLOCK)
+		DHParams()
 		{
-#ifdef _WIN32
-			gnutls_transport_set_errno(session->sess, EAGAIN);
-#else
-			errno = EAGAIN;
-#endif
-			return -1;
+			ThrowOnError(gnutls_dh_params_init(&dh_params), "gnutls_dh_params_init() failed");
 		}
 
-		int rv = ServerInstance->SE->Recv(session->socket, reinterpret_cast<char *>(buffer), size, 0);
+	 public:
+		/** Import */
+		static std::auto_ptr<DHParams> Import(const std::string& dhstr)
+		{
+			std::auto_ptr<DHParams> dh(new DHParams);
+			int ret = gnutls_dh_params_import_pkcs3(dh->dh_params, Datum(dhstr).get(), GNUTLS_X509_FMT_PEM);
+			ThrowOnError(ret, "Unable to import DH params");
+			return dh;
+		}
 
-#ifdef _WIN32
-		if (rv < 0)
+		/** Generate */
+		static std::auto_ptr<DHParams> Generate(unsigned int bits)
 		{
-			/* Windows doesn't use errno, but gnutls does, so check SocketEngine::IgnoreError()
-			 * and then set errno appropriately.
-			 * The gnutls library may also have a different errno variable than us, see
-			 * gnutls_transport_set_errno(3).
-			 */
-			gnutls_transport_set_errno(session->sess, SocketEngine::IgnoreError() ? EAGAIN : errno);
+			std::auto_ptr<DHParams> dh(new DHParams);
+			ThrowOnError(gnutls_dh_params_generate2(dh->dh_params, bits), "Unable to generate DH params");
+			return dh;
 		}
-#endif
 
-		if (rv < (int)size)
-			ServerInstance->SE->ChangeEventMask(session->socket, FD_READ_WILL_BLOCK);
-		return rv;
-	}
+		~DHParams()
+		{
+			gnutls_dh_params_deinit(dh_params);
+		}
 
-	static ssize_t gnutls_push_wrapper(gnutls_transport_ptr_t session_wrap, const void* buffer, size_t size)
+		const gnutls_dh_params_t& get() const { return dh_params; }
+	};
+
+	class X509Key
 	{
-		issl_session* session = reinterpret_cast<issl_session*>(session_wrap);
-		if (session->socket->GetEventMask() & FD_WRITE_WILL_BLOCK)
+		/** Ensure that the key is deinited in case the constructor of X509Key throws
+		 */
+		class RAIIKey
 		{
-#ifdef _WIN32
-			gnutls_transport_set_errno(session->sess, EAGAIN);
-#else
-			errno = EAGAIN;
-#endif
-			return -1;
-		}
+		 public:
+			gnutls_x509_privkey_t key;
 
-		int rv = ServerInstance->SE->Send(session->socket, reinterpret_cast<const char *>(buffer), size, 0);
+			RAIIKey()
+			{
+				ThrowOnError(gnutls_x509_privkey_init(&key), "gnutls_x509_privkey_init() failed");
+			}
 
-#ifdef _WIN32
-		if (rv < 0)
+			~RAIIKey()
+			{
+				gnutls_x509_privkey_deinit(key);
+			}
+		} key;
+
+	 public:
+		/** Import */
+		X509Key(const std::string& keystr)
 		{
-			/* Windows doesn't use errno, but gnutls does, so check SocketEngine::IgnoreError()
-			 * and then set errno appropriately.
-			 * The gnutls library may also have a different errno variable than us, see
-			 * gnutls_transport_set_errno(3).
-			 */
-			gnutls_transport_set_errno(session->sess, SocketEngine::IgnoreError() ? EAGAIN : errno);
+			int ret = gnutls_x509_privkey_import(key.key, Datum(keystr).get(), GNUTLS_X509_FMT_PEM);
+			ThrowOnError(ret, "Unable to import private key");
 		}
-#endif
-
-		if (rv < (int)size)
-			ServerInstance->SE->ChangeEventMask(session->socket, FD_WRITE_WILL_BLOCK);
-		return rv;
-	}
 
- public:
+		gnutls_x509_privkey_t& get() { return key.key; }
+	};
 
-	ModuleSSLGnuTLS()
-		: starttls(this), capHandler(this, "tls"), iohook(this, "ssl/gnutls", SERVICE_IOHOOK)
+	class X509CertList
 	{
-#ifndef GNUTLS_HAS_RND
-		gcry_control (GCRYCTL_INITIALIZATION_FINISHED, 0);
-#endif
+		std::vector<gnutls_x509_crt_t> certs;
 
-		sessions = new issl_session[ServerInstance->SE->GetMaxFds()];
+	 public:
+		/** Import */
+		X509CertList(const std::string& certstr)
+		{
+			unsigned int certcount = 3;
+			certs.resize(certcount);
+			Datum datum(certstr);
 
-		gnutls_global_init(); // This must be called once in the program
-	}
+			int ret = gnutls_x509_crt_list_import(raw(), &certcount, datum.get(), GNUTLS_X509_FMT_PEM, GNUTLS_X509_CRT_LIST_IMPORT_FAIL_IF_EXCEED);
+			if (ret == GNUTLS_E_SHORT_MEMORY_BUFFER)
+			{
+				// the buffer wasn't big enough to hold all certs but gnutls changed certcount to the number of available certs,
+				// try again with a bigger buffer
+				certs.resize(certcount);
+				ret = gnutls_x509_crt_list_import(raw(), &certcount, datum.get(), GNUTLS_X509_FMT_PEM, GNUTLS_X509_CRT_LIST_IMPORT_FAIL_IF_EXCEED);
+			}
 
-	void init()
-	{
-		currconf = new SSLConfig;
-		InitSSLConfig(currconf);
+			ThrowOnError(ret, "Unable to load certificates");
 
-		ServerInstance->GenRandom = &randhandler;
+			// Resize the vector to the actual number of certs because we rely on its size being correct
+			// when deallocating the certs
+			certs.resize(certcount);
+		}
 
-		Implementation eventlist[] = { I_On005Numeric, I_OnRehash, I_OnModuleRehash, I_OnUserConnect,
-			I_OnEvent, I_OnHookIO };
-		ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
+		~X509CertList()
+		{
+			for (std::vector<gnutls_x509_crt_t>::iterator i = certs.begin(); i != certs.end(); ++i)
+				gnutls_x509_crt_deinit(*i);
+		}
 
-		ServerInstance->Modules->AddService(iohook);
-		ServerInstance->Modules->AddService(starttls);
-	}
+		gnutls_x509_crt_t* raw() { return &certs[0]; }
+		unsigned int size() const { return certs.size(); }
+	};
 
-	void OnRehash(User* user)
+	class X509CRL : public refcountbase
 	{
-		sslports.clear();
+		class RAIICRL
+		{
+		 public:
+			gnutls_x509_crl_t crl;
+
+			RAIICRL()
+			{
+				ThrowOnError(gnutls_x509_crl_init(&crl), "gnutls_x509_crl_init() failed");
+			}
 
-		ConfigTag* Conf = ServerInstance->Config->ConfValue("gnutls");
-		starttls.enabled = Conf->getBool("starttls", true);
+			~RAIICRL()
+			{
+				gnutls_x509_crl_deinit(crl);
+			}
+		} crl;
 
-		if (Conf->getBool("showports", true))
+	 public:
+		/** Import */
+		X509CRL(const std::string& crlstr)
 		{
-			sslports = Conf->getString("advertisedports");
-			if (!sslports.empty())
-				return;
+			int ret = gnutls_x509_crl_import(get(), Datum(crlstr).get(), GNUTLS_X509_FMT_PEM);
+			ThrowOnError(ret, "Unable to load certificate revocation list");
+		}
 
-			for (size_t i = 0; i < ServerInstance->ports.size(); i++)
-			{
-				ListenSocket* port = ServerInstance->ports[i];
-				if (port->bind_tag->getString("ssl") != "gnutls")
-					continue;
+		gnutls_x509_crl_t& get() { return crl.crl; }
+	};
+
+#ifdef GNUTLS_NEW_PRIO_API
+	class Priority
+	{
+		gnutls_priority_t priority;
 
-				const std::string& portid = port->bind_desc;
-				ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %s", portid.c_str());
+	 public:
+		Priority(const std::string& priorities)
+		{
+			// Try to set the priorities for ciphers, kex methods etc. to the user supplied string
+			// If the user did not supply anything then the string is already set to "NORMAL"
+			const char* priocstr = priorities.c_str();
+			const char* prioerror;
 
-				if (port->bind_tag->getString("type", "clients") == "clients" && port->bind_addr != "127.0.0.1")
-				{
-					/*
-					 * Found an SSL port for clients that is not bound to 127.0.0.1 and handled by us, display
-					 * the IP:port in ISUPPORT.
-					 *
-					 * We used to advertise all ports seperated by a ';' char that matched the above criteria,
-					 * but this resulted in too long ISUPPORT lines if there were lots of ports to be displayed.
-					 * To solve this by default we now only display the first IP:port found and let the user
-					 * configure the exact value for the 005 token, if necessary.
-					 */
-					sslports = portid;
-					break;
-				}
+			int ret = gnutls_priority_init(&priority, priocstr, &prioerror);
+			if (ret < 0)
+			{
+				// gnutls did not understand the user supplied string
+				throw Exception("Unable to initialize priorities to \"" + priorities + "\": " + gnutls_strerror(ret) + " Syntax error at position " + ConvToStr((unsigned int) (prioerror - priocstr)));
 			}
 		}
-	}
 
-	void OnModuleRehash(User* user, const std::string &param)
-	{
-		if(param != "ssl")
-			return;
+		~Priority()
+		{
+			gnutls_priority_deinit(priority);
+		}
 
-		reference<SSLConfig> newconf = new SSLConfig;
-		try
+		void SetupSession(gnutls_session_t sess)
 		{
-			InitSSLConfig(newconf);
+			gnutls_priority_set(sess, priority);
 		}
-		catch (ModuleException& ex)
+	};
+#else
+	/** Dummy class, used when gnutls_priority_set() is not available
+	 */
+	class Priority
+	{
+	 public:
+		Priority(const std::string& priorities)
 		{
-			ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT, "m_ssl_gnutls: Not applying new config. %s", ex.GetReason());
-			return;
+			if (priorities != "NORMAL")
+				throw Exception("You've set a non-default priority string, but GnuTLS lacks support for it");
 		}
 
-		ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT, "m_ssl_gnutls: Applying new config, old config is in use by %d connection(s)", currconf->GetReferenceCount()-1);
-		currconf = newconf;
-	}
+		static void SetupSession(gnutls_session_t sess)
+		{
+			// Always set the default priorities
+			gnutls_set_default_priority(sess);
+		}
+	};
+#endif
 
-	void InitSSLConfig(SSLConfig* config)
+	class CertCredentials
 	{
-		ServerInstance->Logs->Log("m_ssl_gnutls", DEBUG, "Initializing new SSLConfig %p", (void*)config);
+		/** DH parameters associated with these credentials
+		 */
+		std::auto_ptr<DHParams> dh;
 
-		std::string keyfile;
-		std::string certfile;
-		std::string cafile;
-		std::string crlfile;
-		OnRehash(NULL);
+	 protected:
+		gnutls_certificate_credentials_t cred;
+
+	 public:
+		CertCredentials()
+		{
+			ThrowOnError(gnutls_certificate_allocate_credentials(&cred), "Cannot allocate certificate credentials");
+		}
 
-		ConfigTag* Conf = ServerInstance->Config->ConfValue("gnutls");
+		~CertCredentials()
+		{
+			gnutls_certificate_free_credentials(cred);
+		}
 
-		cafile = Conf->getString("cafile", CONFIG_PATH "/ca.pem");
-		crlfile	= Conf->getString("crlfile", CONFIG_PATH "/crl.pem");
-		certfile = Conf->getString("certfile", CONFIG_PATH "/cert.pem");
-		keyfile	= Conf->getString("keyfile", CONFIG_PATH "/key.pem");
-		dh_bits	= Conf->getInt("dhbits");
-		std::string hashname = Conf->getString("hash", "md5");
+		/** Associates these credentials with the session
+		 */
+		void SetupSession(gnutls_session_t sess)
+		{
+			gnutls_credentials_set(sess, GNUTLS_CRD_CERTIFICATE, cred);
+		}
 
-		// The GnuTLS manual states that the gnutls_set_default_priority()
-		// call we used previously when initializing the session is the same
-		// as setting the "NORMAL" priority string.
-		// Thus if the setting below is not in the config we will behave exactly
-		// the same as before, when the priority setting wasn't available.
-		std::string priorities = Conf->getString("priority", "NORMAL");
+		/** Set the given DH parameters to be used with these credentials
+		 */
+		void SetDH(std::auto_ptr<DHParams>& DH)
+		{
+			dh = DH;
+			gnutls_certificate_set_dh_params(cred, dh->get());
+		}
+	};
 
-		if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
-			dh_bits = 1024;
+	class X509Credentials : public CertCredentials
+	{
+		/** Private key
+		 */
+		X509Key key;
 
-		if (hashname == "md5")
-			hash = GNUTLS_DIG_MD5;
-		else if (hashname == "sha1")
-			hash = GNUTLS_DIG_SHA1;
-#ifdef INSPIRCD_GNUTLS_ENABLE_SHA256_FINGERPRINT
-		else if (hashname == "sha256")
-			hash = GNUTLS_DIG_SHA256;
-#endif
-		else
-			throw ModuleException("Unknown hash type " + hashname);
+		/** Certificate list, presented to the peer
+		 */
+		X509CertList certs;
 
+		/** Trusted CA, may be NULL
+		 */
+		std::auto_ptr<X509CertList> trustedca;
 
-		int ret;
+		/** Certificate revocation list, may be NULL
+		 */
+		std::auto_ptr<X509CRL> crl;
 
-		gnutls_certificate_credentials_t& x509_cred = config->x509_cred;
+		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, cert_cb_last_param_type* st);
 
-		ret = gnutls_certificate_allocate_credentials(&x509_cred);
-		if (ret < 0)
+	 public:
+		X509Credentials(const std::string& certstr, const std::string& keystr)
+			: key(keystr)
+			, certs(certstr)
 		{
-			// Set to NULL because we can't be sure what value is in it and we must not try to
-			// deallocate it in case of an error
-			x509_cred = NULL;
-			throw ModuleException("Failed to allocate certificate credentials: " + std::string(gnutls_strerror(ret)));
-		}
+			// Throwing is ok here, the destructor of Credentials is called in that case
+			int ret = gnutls_certificate_set_x509_key(cred, certs.raw(), certs.size(), key.get());
+			ThrowOnError(ret, "Unable to set cert/key pair");
 
-		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));
+#ifdef GNUTLS_NEW_CERT_CALLBACK_API
+			gnutls_certificate_set_retrieve_function(cred, cert_callback);
+#else
+			gnutls_certificate_client_set_retrieve_function(cred, cert_callback);
+#endif
+		}
 
-		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));
+		/** Sets the trusted CA and the certificate revocation list
+		 * to use when verifying certificates
+		 */
+		void SetCA(std::auto_ptr<X509CertList>& certlist, std::auto_ptr<X509CRL>& CRL)
+		{
+			// Do nothing if certlist is NULL
+			if (certlist.get())
+			{
+				int ret = gnutls_certificate_set_x509_trust(cred, certlist->raw(), certlist->size());
+				ThrowOnError(ret, "gnutls_certificate_set_x509_trust() failed");
 
-		FileReader reader;
+				if (CRL.get())
+				{
+					ret = gnutls_certificate_set_x509_crl(cred, &CRL->get(), 1);
+					ThrowOnError(ret, "gnutls_certificate_set_x509_crl() failed");
+				}
 
-		reader.LoadFile(certfile);
-		std::string cert_string = reader.Contents();
-		gnutls_datum_t cert_datum = { (unsigned char*)cert_string.data(), static_cast<unsigned int>(cert_string.length()) };
+				trustedca = certlist;
+				crl = CRL;
+			}
+		}
+	};
 
-		reader.LoadFile(keyfile);
-		std::string key_string = reader.Contents();
-		gnutls_datum_t key_datum = { (unsigned char*)key_string.data(), static_cast<unsigned int>(key_string.length()) };
+	class DataReader
+	{
+		int retval;
+#ifdef INSPIRCD_GNUTLS_HAS_RECV_PACKET
+		gnutls_packet_t packet;
 
-		std::vector<gnutls_x509_crt_t>& x509_certs = config->x509_certs;
+	 public:
+		DataReader(gnutls_session_t sess)
+		{
+			// Using the packet API avoids the final copy of the data which GnuTLS does if we supply
+			// our own buffer. Instead, we get the buffer containing the data from GnuTLS and copy it
+			// to the recvq directly from there in appendto().
+			retval = gnutls_record_recv_packet(sess, &packet);
+		}
 
-		// If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
-		unsigned int certcount = 3;
-		x509_certs.resize(certcount);
-		ret = gnutls_x509_crt_list_import(&x509_certs[0], &certcount, &cert_datum, GNUTLS_X509_FMT_PEM, GNUTLS_X509_CRT_LIST_IMPORT_FAIL_IF_EXCEED);
-		if (ret == GNUTLS_E_SHORT_MEMORY_BUFFER)
+		void appendto(std::string& recvq)
 		{
-			// the buffer wasn't big enough to hold all certs but gnutls updated certcount to the number of available certs, try again with a bigger buffer
-			x509_certs.resize(certcount);
-			ret = gnutls_x509_crt_list_import(&x509_certs[0], &certcount, &cert_datum, GNUTLS_X509_FMT_PEM, GNUTLS_X509_CRT_LIST_IMPORT_FAIL_IF_EXCEED);
+			// Copy data from GnuTLS buffers to recvq
+			gnutls_datum_t datum;
+			gnutls_packet_get(packet, &datum, NULL);
+			recvq.append(reinterpret_cast<const char*>(datum.data), datum.size);
+
+			gnutls_packet_deinit(packet);
 		}
+#else
+		char* const buffer;
 
-		if (ret <= 0)
+	 public:
+		DataReader(gnutls_session_t sess)
+			: buffer(ServerInstance->GetReadBuffer())
 		{
-			// clear the vector so we won't call gnutls_x509_crt_deinit() on the (uninited) certs later
-			x509_certs.clear();
-			throw ModuleException("Unable to load GnuTLS server certificate (" + certfile + "): " + ((ret < 0) ? (std::string(gnutls_strerror(ret))) : "No certs could be read"));
+			// Read data from GnuTLS buffers into ReadBuffer
+			retval = gnutls_record_recv(sess, buffer, ServerInstance->Config->NetBufferSize);
 		}
-		x509_certs.resize(ret);
 
-		gnutls_x509_privkey_t& x509_key = config->x509_key;
-		if (gnutls_x509_privkey_init(&x509_key) < 0)
+		void appendto(std::string& recvq)
 		{
-			// Make sure the destructor does not try to deallocate this, see above
-			x509_key = NULL;
-			throw ModuleException("Unable to initialize private key");
+			// Copy data from ReadBuffer to recvq
+			recvq.append(buffer, retval);
 		}
+#endif
 
-		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)));
+		int ret() const { return retval; }
+	};
 
-		if((ret = gnutls_certificate_set_x509_key(x509_cred, &x509_certs[0], certcount, x509_key)) < 0)
-			throw ModuleException("Unable to set GnuTLS cert/key pair: " + std::string(gnutls_strerror(ret)));
+	class Profile : public refcountbase
+	{
+		/** Name of this profile
+		 */
+		const std::string name;
 
-		#ifdef GNUTLS_NEW_PRIO_API
-		// Try to set the priorities for ciphers, kex methods etc. to the user supplied string
-		// If the user did not supply anything then the string is already set to "NORMAL"
-		const char* priocstr = priorities.c_str();
-		const char* prioerror;
+		/** X509 certificate(s) and key
+		 */
+		X509Credentials x509cred;
 
-		gnutls_priority_t& priority = config->priority;
-		if ((ret = gnutls_priority_init(&priority, priocstr, &prioerror)) < 0)
-		{
-			// gnutls did not understand the user supplied string, log and fall back to the default priorities
-			ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to set priorities to \"%s\": %s Syntax error at position %u, falling back to default (NORMAL)", priorities.c_str(), gnutls_strerror(ret), (unsigned int) (prioerror - priocstr));
-			gnutls_priority_init(&priority, "NORMAL", NULL);
-		}
+		/** The minimum length in bits for the DH prime to be accepted as a client
+		 */
+		unsigned int min_dh_bits;
 
-		#else
-		if (priorities != "NORMAL")
-			ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: You've set <gnutls:priority> to a value other than the default, but this is only supported with GnuTLS v2.1.7 or newer. Your GnuTLS version is older than that so the option will have no effect.");
-		#endif
+		/** Hashing algorithm to use when generating certificate fingerprints
+		 */
+		Hash hash;
 
-		#if(GNUTLS_VERSION_MAJOR < 2 || ( GNUTLS_VERSION_MAJOR == 2 && GNUTLS_VERSION_MINOR < 12 ) )
-		gnutls_certificate_client_set_retrieve_function (x509_cred, cert_callback);
-		#else
-		gnutls_certificate_set_retrieve_function (x509_cred, cert_callback);
-		#endif
+		/** Priorities for ciphers, compression methods, etc.
+		 */
+		Priority priority;
+
+		Profile(const std::string& profilename, const std::string& certstr, const std::string& keystr,
+				std::auto_ptr<DHParams>& DH, unsigned int mindh, const std::string& hashstr,
+				const std::string& priostr, std::auto_ptr<X509CertList>& CA, std::auto_ptr<X509CRL>& CRL)
+			: name(profilename)
+			, x509cred(certstr, keystr)
+			, min_dh_bits(mindh)
+			, hash(hashstr)
+			, priority(priostr)
+		{
+			x509cred.SetDH(DH);
+			x509cred.SetCA(CA, CRL);
+		}
 
-		gnutls_dh_params_t& dh_params = config->dh_params;
-		ret = gnutls_dh_params_init(&dh_params);
-		if (ret < 0)
+		static std::string ReadFile(const std::string& filename)
 		{
-			// Make sure the destructor does not try to deallocate this, see above
-			dh_params = NULL;
-			ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to initialise DH parameters: %s", gnutls_strerror(ret));
-			return;
+			FileReader reader(filename);
+			std::string ret = reader.GetString();
+			if (ret.empty())
+				throw Exception("Cannot read file " + filename);
+			return ret;
 		}
 
-		std::string dhfile = Conf->getString("dhfile");
-		if (!dhfile.empty())
+	 public:
+		static reference<Profile> Create(const std::string& profilename, ConfigTag* tag)
 		{
-			// Try to load DH params from file
-			reader.LoadFile(dhfile);
-			std::string dhstring = reader.Contents();
-			gnutls_datum_t dh_datum = { (unsigned char*)dhstring.data(), static_cast<unsigned int>(dhstring.length()) };
+			std::string certstr = ReadFile(tag->getString("certfile", "cert.pem"));
+			std::string keystr = ReadFile(tag->getString("keyfile", "key.pem"));
 
-			if ((ret = gnutls_dh_params_import_pkcs3(dh_params, &dh_datum, GNUTLS_X509_FMT_PEM)) < 0)
+			std::auto_ptr<DHParams> dh;
+			int gendh = tag->getInt("gendh");
+			if (gendh)
 			{
-				// File unreadable or GnuTLS was unhappy with the contents, generate the DH primes now
-				ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT, "m_ssl_gnutls.so: Generating DH parameters because I failed to load them from file '%s': %s", dhfile.c_str(), gnutls_strerror(ret));
-				GenerateDHParams(dh_params);
+				gendh = (gendh < 1024 ? 1024 : gendh);
+				dh = DHParams::Generate(gendh);
 			}
+			else
+				dh = DHParams::Import(ReadFile(tag->getString("dhfile", "dhparams.pem")));
+
+			// Use default priority string if this tag does not specify one
+			std::string priostr = tag->getString("priority", "NORMAL");
+			unsigned int mindh = tag->getInt("mindhbits", 1024);
+			std::string hashstr = tag->getString("hash", "md5");
+
+			// Load trusted CA and revocation list, if set
+			std::auto_ptr<X509CertList> ca;
+			std::auto_ptr<X509CRL> crl;
+			std::string filename = tag->getString("cafile");
+			if (!filename.empty())
+			{
+				ca.reset(new X509CertList(ReadFile(filename)));
+
+				filename = tag->getString("crlfile");
+				if (!filename.empty())
+					crl.reset(new X509CRL(ReadFile(filename)));
+			}
+
+			return new Profile(profilename, certstr, keystr, dh, mindh, hashstr, priostr, ca, crl);
 		}
-		else
+
+		/** Set up the given session with the settings in this profile
+		 */
+		void SetupSession(gnutls_session_t sess)
 		{
-			GenerateDHParams(dh_params);
+			priority.SetupSession(sess);
+			x509cred.SetupSession(sess);
+			gnutls_dh_set_prime_bits(sess, min_dh_bits);
 		}
 
-		gnutls_certificate_set_dh_params(x509_cred, dh_params);
-	}
+		const std::string& GetName() const { return name; }
+		X509Credentials& GetX509Credentials() { return x509cred; }
+		gnutls_digest_algorithm_t GetHash() const { return hash.get(); }
+	};
+}
+
+class GnuTLSIOHook : public SSLIOHook
+{
+ private:
+	gnutls_session_t sess;
+	issl_status status;
+	reference<GnuTLS::Profile> profile;
 
-	void GenerateDHParams(gnutls_dh_params_t dh_params)
+	void InitSession(StreamSocket* user, bool me_server)
 	{
- 		// 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.
+		gnutls_init(&sess, me_server ? GNUTLS_SERVER : GNUTLS_CLIENT);
 
-		int ret;
+		profile->SetupSession(sess);
+		gnutls_transport_set_ptr(sess, reinterpret_cast<gnutls_transport_ptr_t>(user));
+		gnutls_transport_set_push_function(sess, gnutls_push_wrapper);
+		gnutls_transport_set_pull_function(sess, gnutls_pull_wrapper);
 
-		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));
+		if (me_server)
+			gnutls_certificate_server_set_request(sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 	}
 
-	~ModuleSSLGnuTLS()
+	void CloseSession()
 	{
-		currconf = NULL;
-
-		gnutls_global_deinit();
-		delete[] sessions;
-		ServerInstance->GenRandom = &ServerInstance->HandleGenRandom;
+		if (this->sess)
+		{
+			gnutls_bye(this->sess, GNUTLS_SHUT_WR);
+			gnutls_deinit(this->sess);
+		}
+		sess = NULL;
+		certificate = NULL;
+		status = ISSL_NONE;
 	}
 
-	void OnCleanup(int target_type, void* item)
+	// Returns 1 if handshake succeeded, 0 if it is still in progress, -1 if it failed
+	int Handshake(StreamSocket* user)
 	{
-		if(target_type == TYPE_USER)
-		{
-			LocalUser* user = IS_LOCAL(static_cast<User*>(item));
+		int ret = gnutls_handshake(this->sess);
 
-			if (user && user->eh.GetIOHook() == this)
+		if (ret < 0)
+		{
+			if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 			{
-				// 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");
+				// Handshake needs resuming later, read() or write() would have blocked.
+				this->status = ISSL_HANDSHAKING;
+
+				if (gnutls_record_get_direction(this->sess) == 0)
+				{
+					// gnutls_handshake() wants to read() again.
+					SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
+				}
+				else
+				{
+					// gnutls_handshake() wants to write() again.
+					SocketEngine::ChangeEventMask(user, FD_WANT_NO_READ | FD_WANT_SINGLE_WRITE);
+				}
+
+				return 0;
+			}
+			else
+			{
+				user->SetError("Handshake Failed - " + std::string(gnutls_strerror(ret)));
+				CloseSession();
+				return -1;
 			}
 		}
-	}
+		else
+		{
+			// Change the seesion state
+			this->status = ISSL_HANDSHAKEN;
 
-	Version GetVersion()
-	{
-		return Version("Provides SSL support for clients", VF_VENDOR);
-	}
+			VerifyCertificate();
 
+			// Finish writing, if any left
+			SocketEngine::ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE | FD_ADD_TRIAL_WRITE);
 
-	void On005Numeric(std::string &output)
-	{
-		if (!sslports.empty())
-			output.append(" SSL=" + sslports);
-		if (starttls.enabled)
-			output.append(" STARTTLS");
+			return 1;
+		}
 	}
 
-	void OnHookIO(StreamSocket* user, ListenSocket* lsb)
+	void VerifyCertificate()
 	{
-		if (!user->GetIOHook() && lsb->bind_tag->getString("ssl") == "gnutls")
+		unsigned int certstatus;
+		const gnutls_datum_t* cert_list;
+		int ret;
+		unsigned int cert_list_size;
+		gnutls_x509_crt_t cert;
+		char str[512];
+		unsigned char digest[512];
+		size_t digest_size = sizeof(digest);
+		size_t name_size = sizeof(str);
+		ssl_cert* certinfo = new ssl_cert;
+		this->certificate = 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(this->sess, &certstatus);
+
+		if (ret < 0)
 		{
-			/* Hook the user with our module */
-			user->AddIOHook(this);
+			certinfo->error = std::string(gnutls_strerror(ret));
+			return;
 		}
-	}
 
-	void OnRequest(Request& request)
-	{
-		if (strcmp("GET_SSL_CERT", request.id) == 0)
+		certinfo->invalid = (certstatus & GNUTLS_CERT_INVALID);
+		certinfo->unknownsigner = (certstatus & GNUTLS_CERT_SIGNER_NOT_FOUND);
+		certinfo->revoked = (certstatus & GNUTLS_CERT_REVOKED);
+		certinfo->trusted = !(certstatus & 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(this->sess) != GNUTLS_CRT_X509)
 		{
-			SocketCertificateRequest& req = static_cast<SocketCertificateRequest&>(request);
-			int fd = req.sock->GetFd();
-			issl_session* session = &sessions[fd];
+			certinfo->error = "No X509 keys sent";
+			return;
+		}
 
-			req.cert = session->cert;
+		ret = gnutls_x509_crt_init(&cert);
+		if (ret < 0)
+		{
+			certinfo->error = gnutls_strerror(ret);
+			return;
 		}
-		else if (!strcmp("GET_RAW_SSL_SESSION", request.id))
+
+		cert_list_size = 0;
+		cert_list = gnutls_certificate_get_peers(this->sess, &cert_list_size);
+		if (cert_list == NULL)
 		{
-			SSLRawSessionRequest& req = static_cast<SSLRawSessionRequest&>(request);
-			if ((req.fd >= 0) && (req.fd < ServerInstance->SE->GetMaxFds()))
-				req.data = reinterpret_cast<void*>(sessions[req.fd].sess);
+			certinfo->error = "No certificate was found";
+			goto info_done_dealloc;
 		}
-	}
 
-	void InitSession(StreamSocket* user, bool me_server)
-	{
-		issl_session* session = &sessions[user->GetFd()];
+		/* This is not a real world example, since we only check the first
+		 * certificate in the given chain.
+		 */
 
-		gnutls_init(&session->sess, me_server ? GNUTLS_SERVER : GNUTLS_CLIENT);
-		session->socket = user;
-		session->config = currconf;
+		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;
+		}
 
-		#ifdef GNUTLS_NEW_PRIO_API
-		gnutls_priority_set(session->sess, currconf->priority);
-		#else
-		gnutls_set_default_priority(session->sess);
-		#endif
-		gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, currconf->x509_cred);
-		gnutls_dh_set_prime_bits(session->sess, dh_bits);
-		gnutls_transport_set_ptr(session->sess, reinterpret_cast<gnutls_transport_ptr_t>(session));
-		gnutls_transport_set_push_function(session->sess, gnutls_push_wrapper);
-		gnutls_transport_set_pull_function(session->sess, gnutls_pull_wrapper);
+		if (gnutls_x509_crt_get_dn(cert, str, &name_size) == 0)
+		{
+			std::string& dn = certinfo->dn;
+			dn = str;
+			// Make sure there are no chars in the string that we consider invalid
+			if (dn.find_first_of("\r\n") != std::string::npos)
+				dn.clear();
+		}
 
-		if (me_server)
-			gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
+		name_size = sizeof(str);
+		if (gnutls_x509_crt_get_issuer_dn(cert, str, &name_size) == 0)
+		{
+			std::string& issuer = certinfo->issuer;
+			issuer = str;
+			if (issuer.find_first_of("\r\n") != std::string::npos)
+				issuer.clear();
+		}
+
+		if ((ret = gnutls_x509_crt_get_fingerprint(cert, profile->GetHash(), digest, &digest_size)) < 0)
+		{
+			certinfo->error = gnutls_strerror(ret);
+		}
+		else
+		{
+			certinfo->fingerprint = BinToHex(digest, digest_size);
+		}
 
-		Handshake(session, user);
+		/* 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);
 	}
 
-	void OnStreamSocketAccept(StreamSocket* user, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server)
+	// 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)
 	{
-		issl_session* session = &sessions[user->GetFd()];
-
-		/* For STARTTLS: Don't try and init a session on a socket that already has a session */
-		if (session->sess)
-			return;
+		if (status == ISSL_HANDSHAKEN)
+			return 1;
+		else if (status == ISSL_HANDSHAKING)
+		{
+			// The handshake isn't finished, try to finish it
+			return Handshake(sock);
+		}
 
-		InitSession(user, true);
+		CloseSession();
+		sock->SetError("No SSL session");
+		return -1;
 	}
 
-	void OnStreamSocketConnect(StreamSocket* user)
+	static const char* UnknownIfNULL(const char* str)
 	{
-		InitSession(user, false);
+		return str ? str : "UNKNOWN";
 	}
 
-	void OnStreamSocketClose(StreamSocket* user)
+	static ssize_t gnutls_pull_wrapper(gnutls_transport_ptr_t session_wrap, void* buffer, size_t size)
 	{
-		CloseSession(&sessions[user->GetFd()]);
+		StreamSocket* sock = reinterpret_cast<StreamSocket*>(session_wrap);
+#ifdef _WIN32
+		GnuTLSIOHook* session = static_cast<GnuTLSIOHook*>(sock->GetIOHook());
+#endif
+
+		if (sock->GetEventMask() & FD_READ_WILL_BLOCK)
+		{
+#ifdef _WIN32
+			gnutls_transport_set_errno(session->sess, EAGAIN);
+#else
+			errno = EAGAIN;
+#endif
+			return -1;
+		}
+
+		int rv = SocketEngine::Recv(sock, reinterpret_cast<char *>(buffer), size, 0);
+
+#ifdef _WIN32
+		if (rv < 0)
+		{
+			/* Windows doesn't use errno, but gnutls does, so check SocketEngine::IgnoreError()
+			 * and then set errno appropriately.
+			 * The gnutls library may also have a different errno variable than us, see
+			 * gnutls_transport_set_errno(3).
+			 */
+			gnutls_transport_set_errno(session->sess, SocketEngine::IgnoreError() ? EAGAIN : errno);
+		}
+#endif
+
+		if (rv < (int)size)
+			SocketEngine::ChangeEventMask(sock, FD_READ_WILL_BLOCK);
+		return rv;
 	}
 
-	int OnStreamSocketRead(StreamSocket* user, std::string& recvq)
+	static ssize_t gnutls_push_wrapper(gnutls_transport_ptr_t session_wrap, const void* buffer, size_t size)
 	{
-		issl_session* session = &sessions[user->GetFd()];
+		StreamSocket* sock = reinterpret_cast<StreamSocket*>(session_wrap);
+#ifdef _WIN32
+		GnuTLSIOHook* session = static_cast<GnuTLSIOHook*>(sock->GetIOHook());
+#endif
 
-		if (!session->sess)
+		if (sock->GetEventMask() & FD_WRITE_WILL_BLOCK)
 		{
-			CloseSession(session);
-			user->SetError("No SSL session");
+#ifdef _WIN32
+			gnutls_transport_set_errno(session->sess, EAGAIN);
+#else
+			errno = EAGAIN;
+#endif
 			return -1;
 		}
 
-		if (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE)
-		{
-			// The handshake isn't finished, try to finish it.
+		int rv = SocketEngine::Send(sock, reinterpret_cast<const char *>(buffer), size, 0);
 
-			if(!Handshake(session, user))
-			{
-				if (session->status != ISSL_CLOSING)
-					return 0;
-				return -1;
-			}
+#ifdef _WIN32
+		if (rv < 0)
+		{
+			/* Windows doesn't use errno, but gnutls does, so check SocketEngine::IgnoreError()
+			 * and then set errno appropriately.
+			 * The gnutls library may also have a different errno variable than us, see
+			 * gnutls_transport_set_errno(3).
+			 */
+			gnutls_transport_set_errno(session->sess, SocketEngine::IgnoreError() ? EAGAIN : errno);
 		}
+#endif
 
-		// If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.
+		if (rv < (int)size)
+			SocketEngine::ChangeEventMask(sock, FD_WRITE_WILL_BLOCK);
+		return rv;
+	}
+
+ public:
+	GnuTLSIOHook(IOHookProvider* hookprov, StreamSocket* sock, bool outbound, const reference<GnuTLS::Profile>& sslprofile)
+		: SSLIOHook(hookprov)
+		, sess(NULL)
+		, status(ISSL_NONE)
+		, profile(sslprofile)
+	{
+		InitSession(sock, outbound);
+		sock->AddIOHook(this);
+		Handshake(sock);
+	}
+
+	void OnStreamSocketClose(StreamSocket* user) CXX11_OVERRIDE
+	{
+		CloseSession();
+	}
+
+	int OnStreamSocketRead(StreamSocket* user, std::string& recvq) CXX11_OVERRIDE
+	{
+		// Finish handshake if needed
+		int prepret = PrepareIO(user);
+		if (prepret <= 0)
+			return prepret;
 
-		if (session->status == ISSL_HANDSHAKEN)
+		// If we resumed the handshake then this->status will be ISSL_HANDSHAKEN.
 		{
-			char* buffer = ServerInstance->GetReadBuffer();
-			size_t bufsiz = ServerInstance->Config->NetBufferSize;
-			int ret = gnutls_record_recv(session->sess, buffer, bufsiz);
+			GnuTLS::DataReader reader(sess);
+			int ret = reader.ret();
 			if (ret > 0)
 			{
-				recvq.append(buffer, ret);
+				reader.appendto(recvq);
 				return 1;
 			}
 			else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
@@ -715,267 +911,253 @@ class ModuleSSLGnuTLS : public Module
 			else if (ret == 0)
 			{
 				user->SetError("Connection closed");
-				CloseSession(session);
+				CloseSession();
 				return -1;
 			}
 			else
 			{
 				user->SetError(gnutls_strerror(ret));
-				CloseSession(session);
+				CloseSession();
 				return -1;
 			}
 		}
-		else if (session->status == ISSL_CLOSING)
-			return -1;
-
-		return 0;
 	}
 
-	int OnStreamSocketWrite(StreamSocket* user, std::string& sendq)
+	int OnStreamSocketWrite(StreamSocket* user, std::string& sendq) CXX11_OVERRIDE
 	{
-		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;
-			return -1;
-		}
+		// Finish handshake if needed
+		int prepret = PrepareIO(user);
+		if (prepret <= 0)
+			return prepret;
 
+		// Session is ready for transferring application data
 		int ret = 0;
 
-		if (session->status == ISSL_HANDSHAKEN)
 		{
-			ret = gnutls_record_send(session->sess, sendq.data(), sendq.length());
+			ret = gnutls_record_send(this->sess, sendq.data(), sendq.length());
 
 			if (ret == (int)sendq.length())
 			{
-				ServerInstance->SE->ChangeEventMask(user, FD_WANT_NO_WRITE);
+				SocketEngine::ChangeEventMask(user, FD_WANT_NO_WRITE);
 				return 1;
 			}
 			else if (ret > 0)
 			{
-				sendq = sendq.substr(ret);
-				ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
+				sendq.erase(0, ret);
+				SocketEngine::ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 				return 0;
 			}
 			else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED || ret == 0)
 			{
-				ServerInstance->SE->ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
+				SocketEngine::ChangeEventMask(user, FD_WANT_SINGLE_WRITE);
 				return 0;
 			}
 			else // (ret < 0)
 			{
 				user->SetError(gnutls_strerror(ret));
-				CloseSession(session);
+				CloseSession();
 				return -1;
 			}
 		}
+	}
+
+	void TellCiphersAndFingerprint(LocalUser* user)
+	{
+		if (sess)
+		{
+			std::string text = "*** You are connected using SSL cipher '";
+			GetCiphersuite(text);
+			text += '\'';
+			if (!certificate->fingerprint.empty())
+				text += " and your SSL certificate fingerprint is " + certificate->fingerprint;
 
-		return 0;
+			user->WriteNotice(text);
+		}
 	}
 
-	bool Handshake(issl_session* session, StreamSocket* user)
+	void GetCiphersuite(std::string& out) const
 	{
-		int ret = gnutls_handshake(session->sess);
+		out.append(UnknownIfNULL(gnutls_protocol_get_name(gnutls_protocol_get_version(sess)))).push_back('-');
+		out.append(UnknownIfNULL(gnutls_kx_get_name(gnutls_kx_get(sess)))).push_back('-');
+		out.append(UnknownIfNULL(gnutls_cipher_get_name(gnutls_cipher_get(sess)))).push_back('-');
+		out.append(UnknownIfNULL(gnutls_mac_get_name(gnutls_mac_get(sess))));
+	}
 
-		if (ret < 0)
-		{
-			if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
-			{
-				// Handshake needs resuming later, read() or write() would have blocked.
+	GnuTLS::Profile* GetProfile() { return profile; }
+};
 
-				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
-			{
-				user->SetError("Handshake Failed - " + std::string(gnutls_strerror(ret)));
-				CloseSession(session);
-				session->status = ISSL_CLOSING;
-			}
+int GnuTLS::X509Credentials::cert_callback(gnutls_session_t sess, const gnutls_datum_t* req_ca_rdn, int nreqs, const gnutls_pk_algorithm_t* sign_algos, int sign_algos_length, cert_cb_last_param_type* st)
+{
+#ifndef GNUTLS_NEW_CERT_CALLBACK_API
+	st->type = GNUTLS_CRT_X509;
+#else
+	st->cert_type = GNUTLS_CRT_X509;
+	st->key_type = GNUTLS_PRIVKEY_X509;
+#endif
+	StreamSocket* sock = reinterpret_cast<StreamSocket*>(gnutls_transport_get_ptr(sess));
+	GnuTLS::X509Credentials& cred = static_cast<GnuTLSIOHook*>(sock->GetIOHook())->GetProfile()->GetX509Credentials();
 
-			return false;
-		}
-		else
-		{
-			// Change the seesion state
-			session->status = ISSL_HANDSHAKEN;
+	st->ncerts = cred.certs.size();
+	st->cert.x509 = cred.certs.raw();
+	st->key.x509 = cred.key.get();
+	st->deinit_all = 0;
 
-			VerifyCertificate(session,user);
+	return 0;
+}
 
-			// Finish writing, if any left
-			ServerInstance->SE->ChangeEventMask(user, FD_WANT_POLL_READ | FD_WANT_NO_WRITE | FD_ADD_TRIAL_WRITE);
+class GnuTLSIOHookProvider : public refcountbase, public IOHookProvider
+{
+	reference<GnuTLS::Profile> profile;
 
-			return true;
-		}
+ public:
+ 	GnuTLSIOHookProvider(Module* mod, reference<GnuTLS::Profile>& prof)
+		: IOHookProvider(mod, "ssl/" + prof->GetName(), IOHookProvider::IOH_SSL)
+		, profile(prof)
+	{
+		ServerInstance->Modules->AddService(*this);
 	}
 
-	void OnUserConnect(LocalUser* user)
+	~GnuTLSIOHookProvider()
 	{
-		if (user->eh.GetIOHook() == this)
-		{
-			if (sessions[user->eh.GetFd()].sess)
-			{
-				const gnutls_session_t& sess = sessions[user->eh.GetFd()].sess;
-				std::string cipher = UnknownIfNULL(gnutls_kx_get_name(gnutls_kx_get(sess)));
-				cipher.append("-").append(UnknownIfNULL(gnutls_cipher_get_name(gnutls_cipher_get(sess)))).append("-");
-				cipher.append(UnknownIfNULL(gnutls_mac_get_name(gnutls_mac_get(sess))));
-
-				ssl_cert* cert = sessions[user->eh.GetFd()].cert;
-				if (cert->fingerprint.empty())
-					user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick.c_str(), cipher.c_str());
-				else
-					user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\""
-						" and your SSL fingerprint is %s", user->nick.c_str(), cipher.c_str(), cert->fingerprint.c_str());
-			}
-		}
+		ServerInstance->Modules->DelService(*this);
 	}
 
-	void CloseSession(issl_session* session)
+	void OnAccept(StreamSocket* sock, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server) CXX11_OVERRIDE
 	{
-		if (session->sess)
-		{
-			gnutls_bye(session->sess, GNUTLS_SHUT_WR);
-			gnutls_deinit(session->sess);
-		}
-		session->socket = NULL;
-		session->sess = NULL;
-		session->cert = NULL;
-		session->status = ISSL_NONE;
-		session->config = NULL;
+		new GnuTLSIOHook(this, sock, true, profile);
 	}
 
-	void VerifyCertificate(issl_session* session, StreamSocket* user)
+	void OnConnect(StreamSocket* sock) CXX11_OVERRIDE
 	{
-		if (!session->sess || !user)
-			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;
-		session->cert = certinfo;
+		new GnuTLSIOHook(this, sock, false, profile);
+	}
+};
 
-		/* 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);
+class ModuleSSLGnuTLS : public Module
+{
+	typedef std::vector<reference<GnuTLSIOHookProvider> > ProfileList;
 
-		if (ret < 0)
-		{
-			certinfo->error = std::string(gnutls_strerror(ret));
-			return;
-		}
+	// First member of the class, gets constructed first and destructed last
+	GnuTLS::Init libinit;
+	RandGen randhandler;
+	ProfileList profiles;
 
-		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);
+	void ReadProfiles()
+	{
+		// First, store all profiles in a new, temporary container. If no problems occur, swap the two
+		// containers; this way if something goes wrong we can go back and continue using the current profiles,
+		// avoiding unpleasant situations where no new SSL connections are possible.
+		ProfileList newprofiles;
 
-		/* 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)
+		ConfigTagList tags = ServerInstance->Config->ConfTags("sslprofile");
+		if (tags.first == tags.second)
 		{
-			certinfo->error = "No X509 keys sent";
-			return;
-		}
+			// No <sslprofile> tags found, create a profile named "gnutls" from settings in the <gnutls> block
+			const std::string defname = "gnutls";
+			ConfigTag* tag = ServerInstance->Config->ConfValue(defname);
+			ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "No <sslprofile> tags found; using settings from the <gnutls> tag");
 
-		ret = gnutls_x509_crt_init(&cert);
-		if (ret < 0)
-		{
-			certinfo->error = gnutls_strerror(ret);
-			return;
+			try
+			{
+				reference<GnuTLS::Profile> profile(GnuTLS::Profile::Create(defname, tag));
+				newprofiles.push_back(new GnuTLSIOHookProvider(this, profile));
+			}
+			catch (CoreException& ex)
+			{
+				throw ModuleException("Error while initializing the default SSL profile - " + ex.GetReason());
+			}
 		}
 
-		cert_list_size = 0;
-		cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
-		if (cert_list == NULL)
+		for (ConfigIter i = tags.first; i != tags.second; ++i)
 		{
-			certinfo->error = "No certificate was found";
-			goto info_done_dealloc;
-		}
+			ConfigTag* tag = i->second;
+			if (tag->getString("provider") != "gnutls")
+				continue;
 
-		/* This is not a real world example, since we only check the first
-		 * certificate in the given chain.
-		 */
+			std::string name = tag->getString("name");
+			if (name.empty())
+			{
+				ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Ignoring <sslprofile> tag without name at " + tag->getTagLocation());
+				continue;
+			}
 
-		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;
-		}
+			reference<GnuTLS::Profile> profile;
+			try
+			{
+				profile = GnuTLS::Profile::Create(name, tag);
+			}
+			catch (CoreException& ex)
+			{
+				throw ModuleException("Error while initializing SSL profile \"" + name + "\" at " + tag->getTagLocation() + " - " + ex.GetReason());
+			}
 
-		if (gnutls_x509_crt_get_dn(cert, name, &name_size) == 0)
-		{
-			std::string& dn = certinfo->dn;
-			dn = name;
-			// Make sure there are no chars in the string that we consider invalid
-			if (dn.find_first_of("\r\n") != std::string::npos)
-				dn.clear();
+			newprofiles.push_back(new GnuTLSIOHookProvider(this, profile));
 		}
 
-		name_size = sizeof(name);
-		if (gnutls_x509_crt_get_issuer_dn(cert, name, &name_size) == 0)
-		{
-			std::string& issuer = certinfo->issuer;
-			issuer = name;
-			if (issuer.find_first_of("\r\n") != std::string::npos)
-				issuer.clear();
-		}
+		// New profiles are ok, begin using them
+		// Old profiles are deleted when their refcount drops to zero
+		profiles.swap(newprofiles);
+	}
+
+ public:
+	ModuleSSLGnuTLS()
+	{
+#ifndef GNUTLS_HAS_RND
+		gcry_control (GCRYCTL_INITIALIZATION_FINISHED, 0);
+#endif
+	}
+
+	void init() CXX11_OVERRIDE
+	{
+		ReadProfiles();
+		ServerInstance->GenRandom = &randhandler;
+	}
 
-		if ((ret = gnutls_x509_crt_get_fingerprint(cert, hash, digest, &digest_size)) < 0)
+	void OnModuleRehash(User* user, const std::string &param) CXX11_OVERRIDE
+	{
+		if(param != "ssl")
+			return;
+
+		try
 		{
-			certinfo->error = gnutls_strerror(ret);
+			ReadProfiles();
 		}
-		else
+		catch (ModuleException& ex)
 		{
-			certinfo->fingerprint = irc::hex(digest, digest_size);
+			ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, ex.GetReason() + " Not applying settings.");
 		}
+	}
 
-		/* 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()))
+	~ModuleSSLGnuTLS()
+	{
+		ServerInstance->GenRandom = &ServerInstance->HandleGenRandom;
+	}
+
+	void OnCleanup(int target_type, void* item) CXX11_OVERRIDE
+	{
+		if(target_type == TYPE_USER)
 		{
-			certinfo->error = "Not activated, or expired certificate";
+			LocalUser* user = IS_LOCAL(static_cast<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");
+			}
 		}
+	}
 
-info_done_dealloc:
-		gnutls_x509_crt_deinit(cert);
+	Version GetVersion() CXX11_OVERRIDE
+	{
+		return Version("Provides SSL support for clients", VF_VENDOR);
 	}
 
-	void OnEvent(Event& ev)
+	void OnUserConnect(LocalUser* user) CXX11_OVERRIDE
 	{
-		if (starttls.enabled)
-			capHandler.HandleEvent(ev);
+		IOHook* hook = user->eh.GetIOHook();
+		if (hook && hook->prov->creator == this)
+			static_cast<GnuTLSIOHook*>(hook)->TellCiphersAndFingerprint(user);
 	}
 };