diff --git a/src/sipsess/sess.c b/src/sipsess/sess.c
new file mode 100644
index 0000000..ff505eb
--- /dev/null
+++ b/src/sipsess/sess.c
@@ -0,0 +1,264 @@
+/**
+ * @file sipsess/sess.c  SIP Session Core
+ *
+ * Copyright (C) 2010 Creytiv.com
+ */
+#include <re_types.h>
+#include <re_mem.h>
+#include <re_mbuf.h>
+#include <re_sa.h>
+#include <re_list.h>
+#include <re_hash.h>
+#include <re_fmt.h>
+#include <re_uri.h>
+#include <re_tmr.h>
+#include <re_msg.h>
+#include <re_sip.h>
+#include <re_sipsess.h>
+#include "sipsess.h"
+
+
+static int internal_offer_handler(struct mbuf **descp,
+				  const struct sip_msg *msg, void *arg)
+{
+	(void)descp;
+	(void)msg;
+	(void)arg;
+
+	return ENOSYS;
+}
+
+
+static int internal_answer_handler(const struct sip_msg *msg, void *arg)
+{
+	(void)msg;
+	(void)arg;
+
+	return ENOSYS;
+}
+
+
+static void internal_progress_handler(const struct sip_msg *msg, void *arg)
+{
+	(void)msg;
+	(void)arg;
+}
+
+
+static void internal_establish_handler(const struct sip_msg *msg, void *arg)
+{
+	(void)msg;
+	(void)arg;
+}
+
+
+static void internal_close_handler(int err, const struct sip_msg *msg,
+				   void *arg)
+{
+	(void)err;
+	(void)msg;
+	(void)arg;
+}
+
+
+static bool termwait(struct sipsess *sess)
+{
+	bool wait = false;
+
+	sess->terminated = 1;
+	sess->offerh  = internal_offer_handler;
+	sess->answerh = internal_answer_handler;
+	sess->progrh  = internal_progress_handler;
+	sess->estabh  = internal_establish_handler;
+	sess->infoh   = NULL;
+	sess->referh  = NULL;
+	sess->closeh  = internal_close_handler;
+	sess->arg     = sess;
+
+	tmr_cancel(&sess->tmr);
+
+	if (sess->st) {
+		(void)sip_treply(&sess->st, sess->sip, sess->msg,
+				 486, "Busy Here");
+	}
+
+	if (sess->req) {
+		sip_request_cancel(sess->req);
+		mem_ref(sess);
+		wait = true;
+	}
+
+	if (sess->replyl.head) {
+		mem_ref(sess);
+		wait = true;
+	}
+
+	if (sess->requestl.head) {
+		mem_ref(sess);
+		wait = true;
+	}
+
+	return wait;
+}
+
+
+static bool terminate(struct sipsess *sess)
+{
+	sess->terminated = 2;
+
+	if (!sess->established || sess->peerterm)
+		return false;
+
+	if (sipsess_bye(sess, true))
+		return false;
+
+	mem_ref(sess);
+	return true;
+}
+
+
+static void destructor(void *arg)
+{
+	struct sipsess *sess = arg;
+
+	switch (sess->terminated) {
+
+	case 0:
+		if (termwait(sess))
+			return;
+
+		/*@fallthrough@*/
+
+	case 1:
+		if (terminate(sess))
+			return;
+		break;
+	}
+
+	hash_unlink(&sess->he);
+	tmr_cancel(&sess->tmr);
+	list_flush(&sess->replyl);
+	list_flush(&sess->requestl);
+	mem_deref((void *)sess->msg);
+	mem_deref(sess->req);
+	mem_deref(sess->dlg);
+	mem_deref(sess->auth);
+	mem_deref(sess->cuser);
+	mem_deref(sess->ctype);
+	mem_deref(sess->close_hdrs);
+	mem_deref(sess->hdrs);
+	mem_deref(sess->desc);
+	mem_deref(sess->sock);
+	mem_deref(sess->sip);
+	mem_deref(sess->st);
+}
+
+
+int sipsess_alloc(struct sipsess **sessp, struct sipsess_sock *sock,
+		  const char *cuser, const char *ctype, struct mbuf *desc,
+		  sip_auth_h *authh, void *aarg, bool aref,
+		  sipsess_offer_h *offerh, sipsess_answer_h *answerh,
+		  sipsess_progr_h *progrh, sipsess_estab_h *estabh,
+		  sipsess_info_h *infoh, sipsess_refer_h *referh,
+		  sipsess_close_h *closeh, void *arg)
+{
+	struct sipsess *sess;
+	int err;
+
+	sess = mem_zalloc(sizeof(*sess), destructor);
+	if (!sess)
+		return ENOMEM;
+
+	err = sip_auth_alloc(&sess->auth, authh, aarg, aref);
+	if (err)
+		goto out;
+
+	err = str_dup(&sess->cuser, cuser);
+	if (err)
+		goto out;
+
+	err = str_dup(&sess->ctype, ctype);
+	if (err)
+		goto out;
+
+	sess->sock    = mem_ref(sock);
+	sess->desc    = mem_ref(desc);
+	sess->sip     = mem_ref(sock->sip);
+	sess->offerh  = offerh  ? offerh  : internal_offer_handler;
+	sess->answerh = answerh ? answerh : internal_answer_handler;
+	sess->progrh  = progrh  ? progrh  : internal_progress_handler;
+	sess->estabh  = estabh  ? estabh  : internal_establish_handler;
+	sess->infoh   = infoh;
+	sess->referh  = referh;
+	sess->closeh  = closeh  ? closeh  : internal_close_handler;
+	sess->arg     = arg;
+
+ out:
+	if (err)
+		mem_deref(sess);
+	else
+		*sessp = sess;
+
+	return err;
+}
+
+
+void sipsess_terminate(struct sipsess *sess, int err,
+		       const struct sip_msg *msg)
+{
+	sipsess_close_h *closeh;
+	void *arg;
+
+	if (sess->terminated)
+		return;
+
+	closeh = sess->closeh;
+	arg    = sess->arg;
+
+	if (!termwait(sess))
+		(void)terminate(sess);
+
+	closeh(err, msg, arg);
+}
+
+
+/**
+ * Get the SIP dialog from a SIP Session
+ *
+ * @param sess      SIP Session
+ *
+ * @return SIP Dialog object
+ */
+struct sip_dialog *sipsess_dialog(const struct sipsess *sess)
+{
+	return sess ? sess->dlg : NULL;
+}
+
+
+/**
+ * Set extra SIP headers for inclusion in Session "close" messages
+ * like BYE and 200 OK. Multiple headers can be included.
+ *
+ * @param sess      SIP Session
+ * @param hdrs      Formatted strings with extra SIP Headers
+ *
+ * @return 0 if success, otherwise errorcode
+ */
+int sipsess_set_close_headers(struct sipsess *sess, const char *hdrs, ...)
+{
+	int err = 0;
+	va_list ap;
+
+	if (!sess)
+		return EINVAL;
+
+	sess->close_hdrs = mem_deref(sess->close_hdrs);
+
+	if (hdrs) {
+		va_start(ap, hdrs);
+		err = re_vsdprintf(&sess->close_hdrs, hdrs, ap);
+		va_end(ap);
+	}
+
+	return err;
+}