Isakmp_dpd task added.

src/libcharon/sa/ikev1/tasks/isakmp_dpd.c

@@ -0,0 +1,278 @@
+#include "isakmp_dpd.h"
+
+#include <encoding/payloads/notify_payload.h>
+#include <sa/ikev1/tasks/informational.h>
+
+#include <daemon.h>
+
+#ifdef SLIPSTREAM
+/* Should be the last include */
+#include <ikev2_mem.h>
+#endif /* SLIPSTREAM */
+
+typedef struct private_isakmp_dpd_t private_isakmp_dpd_t;
+
+/**
+ * Private members of a isakmp_dpd_t task.
+ */
+struct private_isakmp_dpd_t {
+
+	/**
+	 * Public methods and task_t interface.
+	 */
+	isakmp_dpd_t public;
+
+	/**
+	 * Sequence number.
+	 */
+	u_int32_t seqnr;
+
+	/**
+	 * Notify payload, only provided for requests.
+	 */
+	notify_payload_t *notify;
+
+	/**
+	 * IKE SA we are serving.
+	 */
+	ike_sa_t *ike_sa;
+};
+
+/**
+ * Get DPD sequence number from notify payload.
+ */
+static bool get_seqnr(notify_payload_t *notify, u_int32_t *seqnr)
+{
+	chunk_t chunk = notify->get_notification_data(notify);
+
+	if( chunk.ptr && chunk.len == 4)
+	{
+		u_int32_t seqnr_read = *((u_int32_t*)chunk.ptr);
+
+		*seqnr = ntohl(seqnr_read);
+
+		return TRUE;
+	}
+
+	DBG1(DBG_IKE, "no DPD seqnr received");
+
+	return FALSE;
+}
+
+/**
+ * Add notify payload to message.
+ */
+static void add_notify(private_isakmp_dpd_t *this, message_t *message, notify_type_t type)
+{
+	notify_payload_t *notify;
+
+	ike_sa_id_t *ike_sa_id;
+	u_int64_t spi_i, spi_r;
+	u_int32_t seqnr;
+	chunk_t spi;
+
+	notify = notify_payload_create_from_protocol_and_type(NOTIFY_V1,
+		PROTO_IKE, type);
+
+	seqnr = htonl(this->seqnr);
+	ike_sa_id = this->ike_sa->get_id(this->ike_sa);
+	spi_i = ike_sa_id->get_initiator_spi(ike_sa_id);
+	spi_r = ike_sa_id->get_responder_spi(ike_sa_id);
+	spi = chunk_cata("cc", chunk_from_thing(spi_i), chunk_from_thing(spi_r));
+
+	notify->set_spi_data(notify, spi);
+	notify->set_notification_data(notify, chunk_from_thing(seqnr));
+
+	message->add_payload(message, (payload_t*)notify);
+}
+
+METHOD(isakmp_dpd_t, get_dpd_seqnr, u_int32_t,
+	private_isakmp_dpd_t *this)
+{
+	return this->seqnr;
+}
+
+METHOD(task_t, build_i, status_t,
+	private_isakmp_dpd_t *this, message_t *message)
+{
+	add_notify(this, message, DPD_R_U_THERE);
+
+	return NEED_MORE;
+}
+
+METHOD(task_t, build_r, status_t,
+			 private_isakmp_dpd_t *this, message_t *message)
+{
+	add_notify(this, message, DPD_R_U_THERE_ACK);
+
+	return SUCCESS;
+}
+
+METHOD(task_t, process_i, status_t,
+	private_isakmp_dpd_t *this, message_t *message)
+{
+	enumerator_t *enumerator;
+	notify_payload_t *notify;
+	notify_type_t type;
+	payload_t *payload;
+	task_t *info_task = NULL;
+
+	enumerator = message->create_payload_enumerator(message);
+	while (enumerator->enumerate(enumerator, &payload))
+	{
+		switch (payload->get_type(payload))
+		{
+			case NOTIFY_V1:
+				notify = (notify_payload_t*)payload;
+				type = notify->get_notify_type(notify);
+
+				if (type == DPD_R_U_THERE_ACK)
+				{
+					u_int32_t seqnr;
+
+					if (!get_seqnr(notify, &seqnr))
+					{
+						return FAILED;
+					}
+
+					if (this->seqnr != seqnr)
+					{
+						DBG1(DBG_IKE, "received DPD Ack with unexpected seqnr (%u) expect (%u)",seqnr,this->seqnr);
+						return SUCCESS;
+					}
+
+					DBG4(DBG_IKE, "received DPD Ack with seqnr (%u)",seqnr);
+
+					return SUCCESS;
+
+				}
+				else if (type == DPD_R_U_THERE)
+				{
+					u_int32_t expected = this->seqnr + 1;
+
+					if (!get_seqnr(notify, &this->seqnr))
+					{
+						return FAILED;
+					}
+
+					if (expected != 1 && this->seqnr != expected)
+					{
+						DBG1(DBG_IKE, "received DPD request with unexpected seqnr (%u) expect (%u)",
+							this->seqnr,expected);
+						return SUCCESS;
+					}
+
+					DBG4(DBG_IKE, "received DPD request with seqnr %u",this->seqnr);
+
+					this->public.task.build = _build_r;
+					return NEED_MORE;
+				}
+				else
+				{
+					info_task = (task_t*)informational_create(this->ike_sa, NULL, 0);
+				}
+				continue;
+
+			default:
+				continue;
+		}
+		break;
+	}
+	enumerator->destroy(enumerator);
+
+	if (info_task)
+	{
+		status_t status = info_task->process(info_task, message);
+		/* Assuming that the informational task will not need to send other replies than dpd */
+		info_task->destroy(info_task);
+		return status;
+	}
+
+	return SUCCESS;
+}
+
+METHOD(task_t, process_r, status_t,
+			 private_isakmp_dpd_t *this, message_t *message)
+{
+	u_int32_t expected = this->seqnr + 1;
+
+	if (this->notify)
+	{
+		if (!get_seqnr(this->notify, &this->seqnr))
+		{
+			return FAILED;
+		}
+
+		if (expected != 1 && this->seqnr != expected)
+		{
+			DBG1(DBG_IKE, "received DPD request with unexpected seqnr (%u) expect (%u)",
+				this->seqnr,expected);
+			return SUCCESS;
+		}
+
+		DBG4(DBG_IKE, "DPD request received with seqnr %u",this->seqnr);
+	}
+	else
+	{
+		DBG1(DBG_IKE, "no notify provided");
+		return FAILED;
+	}
+	return NEED_MORE;
+}
+
+
+METHOD(task_t, get_type, task_type_t,
+	private_isakmp_dpd_t *this)
+{
+	return TASK_ISAKMP_DPD;
+}
+
+
+METHOD(task_t, migrate, void,
+	private_isakmp_dpd_t *this, ike_sa_t *ike_sa)
+{
+	this->ike_sa = ike_sa;
+	this->seqnr = 0;
+
+}
+
+METHOD(task_t, destroy, void,
+	private_isakmp_dpd_t *this)
+{
+	free(this);
+}
+
+/*
+ * Described in header.
+ */
+isakmp_dpd_t *isakmp_dpd_create(ike_sa_t *ike_sa, notify_payload_t *notify, u_int32_t seqnr)
+{
+	private_isakmp_dpd_t *this;
+
+	INIT(this,
+		.public = {
+			.task = {
+				.get_type = _get_type,
+				.migrate = _migrate,
+				.destroy = _destroy,
+			},
+			.get_dpd_seqnr = _get_dpd_seqnr,
+		},
+		.notify = notify,
+		.ike_sa = ike_sa,
+		.seqnr = seqnr,
+	);
+
+	if (!notify)
+	{
+		this->public.task.build = _build_i;
+		this->public.task.process = _process_i;
+	}
+	else
+	{
+		this->public.task.build = _build_r;
+		this->public.task.process = _process_r;
+	}
+
+	return &this->public;
+}