Import upstream release 5.2.1

1 files changed, 931 insertions, 0 deletions

diff --git a/src/libimcv/plugins/imv_attestation/imv_attestation_agent.c b/src/libimcv/plugins/imv_attestation/imv_attestation_agent.c
new file mode 100644
index 000000000..8e3736857
--- /dev/null
+++ b/src/libimcv/plugins/imv_attestation/imv_attestation_agent.c
@@ -0,0 +1,931 @@
+/*
+ * Copyright (C) 2011-2012 Sansar Choinyambuu
+ * Copyright (C) 2011-2014 Andreas Steffen
+ * HSR Hochschule fuer Technik Rapperswil
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+#define _GNU_SOURCE /* for stdndup() */
+#include <string.h>
+
+#include "imv_attestation_agent.h"
+#include "imv_attestation_state.h"
+#include "imv_attestation_process.h"
+#include "imv_attestation_build.h"
+
+#include <imcv.h>
+#include <imv/imv_agent.h>
+#include <imv/imv_msg.h>
+#include <imv/imv_session.h>
+#include <imv/imv_os_info.h>
+#include <ietf/ietf_attr.h>
+#include <ietf/ietf_attr_attr_request.h>
+#include <ietf/ietf_attr_pa_tnc_error.h>
+#include <ietf/ietf_attr_product_info.h>
+#include <ietf/ietf_attr_string_version.h>
+#include <ita/ita_attr.h>
+#include <ita/ita_attr_device_id.h>
+#include <tcg/tcg_attr.h>
+#include <tcg/pts/tcg_pts_attr_meas_algo.h>
+#include <tcg/pts/tcg_pts_attr_proto_caps.h>
+#include <tcg/pts/tcg_pts_attr_req_file_meas.h>
+#include <tcg/pts/tcg_pts_attr_req_file_meta.h>
+#include "tcg/seg/tcg_seg_attr_max_size.h"
+#include "tcg/seg/tcg_seg_attr_seg_env.h"
+#include <pts/pts.h>
+#include <pts/pts_database.h>
+#include <pts/pts_creds.h>
+#include <pts/components/ita/ita_comp_func_name.h>
+
+#include <tncif_pa_subtypes.h>
+
+#include <pen/pen.h>
+#include <utils/debug.h>
+#include <credentials/credential_manager.h>
+#include <collections/linked_list.h>
+
+#define FILE_MEAS_MAX_ATTR_SIZE	100000000
+
+typedef struct private_imv_attestation_agent_t private_imv_attestation_agent_t;
+
+/* Subscribed PA-TNC message subtypes */
+static pen_type_t msg_types[] = {
+	{ PEN_TCG,  PA_SUBTYPE_TCG_PTS },
+	{ PEN_IETF, PA_SUBTYPE_IETF_OPERATING_SYSTEM }
+};
+
+/**
+ * Private data of an imv_attestation_agent_t object.
+ */
+struct private_imv_attestation_agent_t {
+
+	/**
+	 * Public members of imv_attestation_agent_t
+	 */
+	imv_agent_if_t public;
+
+	/**
+	 * IMV agent responsible for generic functions
+	 */
+	imv_agent_t *agent;
+
+	/**
+	 * Supported PTS measurement algorithms
+	 */
+	pts_meas_algorithms_t supported_algorithms;
+
+	/**
+	 * Supported PTS Diffie Hellman Groups
+	 */
+	pts_dh_group_t supported_dh_groups;
+
+	/**
+	 * PTS file measurement database
+	 */
+	pts_database_t *pts_db;
+
+	/**
+	 * PTS credentials
+	 */
+	pts_creds_t *pts_creds;
+
+	/**
+	 * PTS credential manager
+	 */
+	credential_manager_t *pts_credmgr;
+
+};
+
+METHOD(imv_agent_if_t, bind_functions, TNC_Result,
+	private_imv_attestation_agent_t *this, TNC_TNCS_BindFunctionPointer bind_function)
+{
+	return this->agent->bind_functions(this->agent, bind_function);
+}
+
+METHOD(imv_agent_if_t, notify_connection_change, TNC_Result,
+	private_imv_attestation_agent_t *this, TNC_ConnectionID id,
+	TNC_ConnectionState new_state)
+{
+	TNC_IMV_Action_Recommendation rec;
+	imv_state_t *state;
+	imv_session_t *session;
+
+	switch (new_state)
+	{
+		case TNC_CONNECTION_STATE_CREATE:
+			state = imv_attestation_state_create(id);
+			return this->agent->create_state(this->agent, state);
+		case TNC_CONNECTION_STATE_DELETE:
+			return this->agent->delete_state(this->agent, id);
+		case TNC_CONNECTION_STATE_ACCESS_ALLOWED:
+		case TNC_CONNECTION_STATE_ACCESS_ISOLATED:
+		case TNC_CONNECTION_STATE_ACCESS_NONE:
+			if (this->agent->get_state(this->agent, id, &state) && imcv_db)
+			{
+				session = state->get_session(state);
+
+				if (session->get_policy_started(session))
+				{
+					switch (new_state)
+					{
+						case TNC_CONNECTION_STATE_ACCESS_ALLOWED:
+							rec = TNC_IMV_ACTION_RECOMMENDATION_ALLOW;
+							break;
+						case TNC_CONNECTION_STATE_ACCESS_ISOLATED:
+							rec = TNC_IMV_ACTION_RECOMMENDATION_ISOLATE;
+							break;
+						case TNC_CONNECTION_STATE_ACCESS_NONE:
+						default:
+							rec = TNC_IMV_ACTION_RECOMMENDATION_NO_ACCESS;
+					}
+					imcv_db->add_recommendation(imcv_db, session, rec);
+					if (!imcv_db->policy_script(imcv_db, session, FALSE))
+					{
+						DBG1(DBG_IMV, "error in policy script stop");
+					}
+				}
+			}
+			/* fall through to default state */
+		default:
+			return this->agent->change_state(this->agent, id, new_state, NULL);
+	}
+}
+
+/**
+ * Process a received message
+ */
+static TNC_Result receive_msg(private_imv_attestation_agent_t *this,
+							  imv_state_t *state, imv_msg_t *in_msg)
+{
+	imv_msg_t *out_msg;
+	imv_session_t *session;
+	imv_os_info_t *os_info;
+	enumerator_t *enumerator;
+	pa_tnc_attr_t *attr;
+	pen_type_t type;
+	TNC_Result result;
+	chunk_t os_name, os_version;
+	bool fatal_error = FALSE;
+
+	/* generate an outgoing PA-TNC message - we might need it */
+	out_msg = imv_msg_create_as_reply(in_msg);
+	out_msg->set_msg_type(out_msg, msg_types[0]);
+
+	/* parse received PA-TNC message and handle local and remote errors */
+	result = in_msg->receive(in_msg, out_msg, &fatal_error);
+	if (result != TNC_RESULT_SUCCESS)
+	{
+		out_msg->destroy(out_msg);
+		return result;
+	}
+
+	session = state->get_session(state);
+	os_info = session->get_os_info(session);
+
+	/* analyze PA-TNC attributes */
+	enumerator = in_msg->create_attribute_enumerator(in_msg);
+	while (enumerator->enumerate(enumerator, &attr))
+	{
+		type = attr->get_type(attr);
+
+		if (type.vendor_id == PEN_IETF)
+		{
+			switch (type.type)
+			{
+				case IETF_ATTR_PA_TNC_ERROR:
+				{
+					ietf_attr_pa_tnc_error_t *error_attr;
+					pen_type_t error_code;
+					chunk_t msg_info;
+
+					error_attr = (ietf_attr_pa_tnc_error_t*)attr;
+					error_code = error_attr->get_error_code(error_attr);
+
+					if (error_code.vendor_id == PEN_TCG)
+					{
+						msg_info = error_attr->get_msg_info(error_attr);
+
+						DBG1(DBG_IMV, "received TCG-PTS error '%N'",
+							 pts_error_code_names, error_code.type);
+						DBG1(DBG_IMV, "error information: %B", &msg_info);
+						fatal_error = TRUE;
+					}
+					break;
+				}
+				case IETF_ATTR_PRODUCT_INFORMATION:
+				{
+					ietf_attr_product_info_t *attr_cast;
+					pen_t vendor_id;
+
+					state->set_action_flags(state,
+										IMV_ATTESTATION_ATTR_PRODUCT_INFO);
+					attr_cast = (ietf_attr_product_info_t*)attr;
+					os_name = attr_cast->get_info(attr_cast, &vendor_id, NULL);
+					os_info->set_name(os_info, os_name);
+
+					if (vendor_id != PEN_IETF)
+					{
+						DBG1(DBG_IMV, "operating system name is '%.*s' "
+									  "from vendor %N", os_name.len, os_name.ptr,
+									   pen_names, vendor_id);
+					}
+					else
+					{
+						DBG1(DBG_IMV, "operating system name is '%.*s'",
+									   os_name.len, os_name.ptr);
+					}
+					break;
+
+					break;
+				}
+				case IETF_ATTR_STRING_VERSION:
+				{
+					ietf_attr_string_version_t *attr_cast;
+
+					state->set_action_flags(state,
+										IMV_ATTESTATION_ATTR_STRING_VERSION);
+					attr_cast = (ietf_attr_string_version_t*)attr;
+					os_version = attr_cast->get_version(attr_cast, NULL, NULL);
+					os_info->set_version(os_info, os_version);
+
+					if (os_version.len)
+					{
+						DBG1(DBG_IMV, "operating system version is '%.*s'",
+									   os_version.len, os_version.ptr);
+					}
+					break;
+				}
+				default:
+					break;
+			}
+		}
+		else if (type.vendor_id == PEN_ITA)
+		{
+			switch (type.type)
+			{
+				case ITA_ATTR_DEVICE_ID:
+				{
+					chunk_t value;
+
+					state->set_action_flags(state,
+										IMV_ATTESTATION_ATTR_DEVICE_ID);
+
+					value = attr->get_value(attr);
+					DBG1(DBG_IMV, "device ID is %.*s", value.len, value.ptr);
+					session->set_device_id(session, value);
+					break;
+				}
+				default:
+					break;
+			}
+		}
+		else if (type.vendor_id == PEN_TCG)
+		{
+			if (!imv_attestation_process(attr, out_msg, state,
+				this->supported_algorithms, this->supported_dh_groups,
+				this->pts_db, this->pts_credmgr))
+			{
+				result = TNC_RESULT_FATAL;
+				break;
+			}
+		}
+	}
+	enumerator->destroy(enumerator);
+
+	if (fatal_error || result != TNC_RESULT_SUCCESS)
+	{
+		state->set_recommendation(state,
+								TNC_IMV_ACTION_RECOMMENDATION_NO_RECOMMENDATION,
+								TNC_IMV_EVALUATION_RESULT_ERROR);
+		result = out_msg->send_assessment(out_msg);
+		if (result == TNC_RESULT_SUCCESS)
+		{
+			result = this->agent->provide_recommendation(this->agent, state);
+		}
+	}
+	else
+	{
+		/* send PA-TNC message with the EXCL flag set */
+		result = out_msg->send(out_msg, TRUE);
+	}
+	out_msg->destroy(out_msg);
+
+	return result;
+}
+
+METHOD(imv_agent_if_t, receive_message, TNC_Result,
+	private_imv_attestation_agent_t *this, TNC_ConnectionID id,
+	TNC_MessageType msg_type, chunk_t msg)
+{
+	imv_state_t *state;
+	imv_msg_t *in_msg;
+	TNC_Result result;
+
+	if (!this->agent->get_state(this->agent, id, &state))
+	{
+		return TNC_RESULT_FATAL;
+	}
+	in_msg = imv_msg_create_from_data(this->agent, state, id, msg_type, msg);
+	result = receive_msg(this, state, in_msg);
+	in_msg->destroy(in_msg);
+
+	return result;
+}
+
+METHOD(imv_agent_if_t, receive_message_long, TNC_Result,
+	private_imv_attestation_agent_t *this, TNC_ConnectionID id,
+	TNC_UInt32 src_imc_id, TNC_UInt32 dst_imv_id,
+	TNC_VendorID msg_vid, TNC_MessageSubtype msg_subtype, chunk_t msg)
+{
+	imv_state_t *state;
+	imv_msg_t *in_msg;
+	TNC_Result result;
+
+	if (!this->agent->get_state(this->agent, id, &state))
+	{
+		return TNC_RESULT_FATAL;
+	}
+	in_msg = imv_msg_create_from_long_data(this->agent, state, id,
+					src_imc_id, dst_imv_id, msg_vid, msg_subtype, msg);
+	result = receive_msg(this, state, in_msg);
+	in_msg->destroy(in_msg);
+
+	return result;
+}
+
+/**
+ * Build an IETF Attribute Request attribute for missing attributes
+ */
+static pa_tnc_attr_t* build_attr_request(uint32_t received)
+{
+	pa_tnc_attr_t *attr;
+	ietf_attr_attr_request_t *attr_cast;
+
+	attr = ietf_attr_attr_request_create(PEN_RESERVED, 0);
+	attr_cast = (ietf_attr_attr_request_t*)attr;
+
+	if (!(received & IMV_ATTESTATION_ATTR_PRODUCT_INFO) ||
+		!(received & IMV_ATTESTATION_ATTR_STRING_VERSION))
+	{
+		attr_cast->add(attr_cast, PEN_IETF, IETF_ATTR_PRODUCT_INFORMATION);
+		attr_cast->add(attr_cast, PEN_IETF, IETF_ATTR_STRING_VERSION);
+	}
+	if (!(received & IMV_ATTESTATION_ATTR_DEVICE_ID))
+	{
+		attr_cast->add(attr_cast, PEN_ITA,  ITA_ATTR_DEVICE_ID);
+	}
+
+	return attr;
+}
+
+METHOD(imv_agent_if_t, batch_ending, TNC_Result,
+	private_imv_attestation_agent_t *this, TNC_ConnectionID id)
+{
+	imv_msg_t *out_msg;
+	imv_state_t *state;
+	imv_session_t *session;
+	imv_attestation_state_t *attestation_state;
+	imv_attestation_handshake_state_t handshake_state;
+	imv_workitem_t *workitem;
+	TNC_IMV_Action_Recommendation rec;
+	TNC_IMV_Evaluation_Result eval;
+	TNC_IMVID imv_id;
+	TNC_Result result = TNC_RESULT_SUCCESS;
+	pts_t *pts;
+	int pid;
+	uint32_t actions;
+	enumerator_t *enumerator;
+
+	if (!this->agent->get_state(this->agent, id, &state))
+	{
+		return TNC_RESULT_FATAL;
+	}
+	attestation_state = (imv_attestation_state_t*)state;
+	pts = attestation_state->get_pts(attestation_state);
+	handshake_state = attestation_state->get_handshake_state(attestation_state);
+	actions = state->get_action_flags(state);
+	session = state->get_session(state);
+	imv_id = this->agent->get_id(this->agent);
+
+	/* exit if a recommendation has already been provided */
+	if (actions & IMV_ATTESTATION_REC)
+	{
+		return TNC_RESULT_SUCCESS;
+	}
+
+	/* send an IETF attribute request if no platform info was received */
+	if (!(actions & IMV_ATTESTATION_ATTR_REQ))
+	{
+		if ((actions & IMV_ATTESTATION_ATTR_MUST) != IMV_ATTESTATION_ATTR_MUST)
+		{
+			imv_msg_t *os_msg;
+
+			/* create attribute request for missing mandatory attributes */
+			os_msg = imv_msg_create(this->agent, state, id, imv_id,
+									TNC_IMCID_ANY, msg_types[1]);
+			os_msg->add_attribute(os_msg, build_attr_request(actions));
+			result = os_msg->send(os_msg, FALSE);
+			os_msg->destroy(os_msg);
+
+			if (result != TNC_RESULT_SUCCESS)
+			{
+				return result;
+			}
+		 }
+		state->set_action_flags(state, IMV_ATTESTATION_ATTR_REQ);
+	}
+
+	if (!session->get_policy_started(session) &&
+		(actions & IMV_ATTESTATION_ATTR_PRODUCT_INFO) &&
+		(actions & IMV_ATTESTATION_ATTR_STRING_VERSION) &&
+		(actions & IMV_ATTESTATION_ATTR_DEVICE_ID))
+	{
+		if (imcv_db)
+		{
+			/* start the policy script */
+			if (!imcv_db->policy_script(imcv_db, session, TRUE))
+			{
+				DBG1(DBG_IMV, "error in policy script start");
+			}
+		}
+		else
+		{
+			DBG2(DBG_IMV, "no workitems available - no evaluation possible");
+			state->set_recommendation(state,
+									  TNC_IMV_ACTION_RECOMMENDATION_ALLOW,
+									  TNC_IMV_EVALUATION_RESULT_DONT_KNOW);
+			session->set_policy_started(session, TRUE);
+		}
+	}
+
+	if (handshake_state == IMV_ATTESTATION_STATE_INIT)
+	{
+		size_t max_attr_size = FILE_MEAS_MAX_ATTR_SIZE;
+		size_t max_seg_size;
+		seg_contract_t *contract;
+		seg_contract_manager_t *contracts;
+		pa_tnc_attr_t *attr;
+		pts_proto_caps_flag_t flags;
+		char buf[BUF_LEN];
+
+		out_msg = imv_msg_create(this->agent, state, id, imv_id, TNC_IMCID_ANY,
+								 msg_types[0]);
+
+		/* Determine maximum PA-TNC attribute segment size */
+		max_seg_size = state->get_max_msg_len(state)
+								- PA_TNC_HEADER_SIZE
+								- PA_TNC_ATTR_HEADER_SIZE
+								- TCG_SEG_ATTR_SEG_ENV_HEADER
+								- PA_TNC_ATTR_HEADER_SIZE
+								- TCG_SEG_ATTR_MAX_SIZE_SIZE;
+
+		/* Announce support of PA-TNC segmentation to IMC */
+		contract = seg_contract_create(msg_types[0], max_attr_size,
+										max_seg_size, TRUE, imv_id, FALSE);
+		contract->get_info_string(contract, buf, BUF_LEN, TRUE);
+		DBG2(DBG_IMV, "%s", buf);
+		contracts = state->get_contracts(state);
+		contracts->add_contract(contracts, contract);
+		attr = tcg_seg_attr_max_size_create(max_attr_size, max_seg_size, TRUE);
+		out_msg->add_attribute(out_msg, attr);
+
+		/* Send Request Protocol Capabilities attribute */
+		flags = pts->get_proto_caps(pts);
+		attr = tcg_pts_attr_proto_caps_create(flags, TRUE);
+		attr->set_noskip_flag(attr, TRUE);
+		out_msg->add_attribute(out_msg, attr);
+
+		/* Send Measurement Algorithms attribute */
+		attr = tcg_pts_attr_meas_algo_create(this->supported_algorithms, FALSE);
+		attr->set_noskip_flag(attr, TRUE);
+		out_msg->add_attribute(out_msg, attr);
+
+		attestation_state->set_handshake_state(attestation_state,
+										IMV_ATTESTATION_STATE_DISCOVERY);
+
+		/* send these initial PTS attributes and exit */
+		result = out_msg->send(out_msg, FALSE);
+		out_msg->destroy(out_msg);
+
+		return result;
+	}
+
+	/* exit if we are not ready yet for PTS measurements */
+	if (!(actions & IMV_ATTESTATION_ALGO))
+	{
+		return TNC_RESULT_SUCCESS;
+	}
+
+	session->get_session_id(session, &pid, NULL);
+	pts->set_platform_id(pts, pid);
+
+	/* create an empty out message - we might need it */
+	out_msg = imv_msg_create(this->agent, state, id, imv_id, TNC_IMCID_ANY,
+							 msg_types[0]);
+
+	/* establish the PTS measurements to be taken */
+	if (!(actions & IMV_ATTESTATION_FILE_MEAS))
+	{
+		bool is_dir, no_workitems = TRUE;
+		uint32_t delimiter = SOLIDUS_UTF;
+		uint16_t request_id;
+		pa_tnc_attr_t *attr;
+		char *pathname;
+
+		attestation_state->set_handshake_state(attestation_state,
+											   IMV_ATTESTATION_STATE_END);
+
+		enumerator = session->create_workitem_enumerator(session);
+		if (enumerator)
+		{
+			while (enumerator->enumerate(enumerator, &workitem))
+			{
+				if (workitem->get_imv_id(workitem) != TNC_IMVID_ANY)
+				{
+					continue;
+				}
+
+				switch (workitem->get_type(workitem))
+				{
+					case IMV_WORKITEM_FILE_REF_MEAS:
+					case IMV_WORKITEM_FILE_MEAS:
+					case IMV_WORKITEM_FILE_META:
+						is_dir = FALSE;
+						break;
+					case IMV_WORKITEM_DIR_REF_MEAS:
+					case IMV_WORKITEM_DIR_MEAS:
+					case IMV_WORKITEM_DIR_META:
+						is_dir = TRUE;
+						break;
+					case IMV_WORKITEM_TPM_ATTEST:
+					{
+						pts_component_t *comp;
+						pts_comp_func_name_t *comp_name;
+						bool no_d_flag, no_t_flag;
+						char result_str[BUF_LEN];
+
+						workitem->set_imv_id(workitem, imv_id);
+						no_workitems = FALSE;
+						no_d_flag = !(pts->get_proto_caps(pts) & PTS_PROTO_CAPS_D);
+						no_t_flag = !(pts->get_proto_caps(pts) & PTS_PROTO_CAPS_T);
+						if (no_d_flag || no_t_flag)
+						{
+							snprintf(result_str, BUF_LEN, "%s%s%s",
+									(no_t_flag) ? "no TPM available" : "",
+									(no_t_flag && no_d_flag) ? ", " : "",
+									(no_d_flag) ? "no DH nonce negotiation" : "");
+							eval = TNC_IMV_EVALUATION_RESULT_ERROR;
+							session->remove_workitem(session, enumerator);
+							rec = workitem->set_result(workitem, result_str, eval);
+							state->update_recommendation(state, rec, eval);
+							imcv_db->finalize_workitem(imcv_db, workitem);
+							workitem->destroy(workitem);
+							continue;
+						}
+
+						/* do TPM BIOS measurements */
+						if (strchr(workitem->get_arg_str(workitem), 'B'))
+						{
+							comp_name = pts_comp_func_name_create(PEN_ITA,
+											PTS_ITA_COMP_FUNC_NAME_IMA,
+											PTS_ITA_QUALIFIER_FLAG_KERNEL |
+											PTS_ITA_QUALIFIER_TYPE_TRUSTED);
+							comp = attestation_state->create_component(
+											attestation_state, comp_name,
+											0, this->pts_db);
+							if (!comp)
+							{
+								comp_name->log(comp_name, "unregistered ");
+								comp_name->destroy(comp_name);
+							}
+						}
+
+						/* do TPM IMA measurements */
+						if (strchr(workitem->get_arg_str(workitem), 'I'))
+						{
+							comp_name = pts_comp_func_name_create(PEN_ITA,
+											PTS_ITA_COMP_FUNC_NAME_IMA,
+											PTS_ITA_QUALIFIER_FLAG_KERNEL |
+											PTS_ITA_QUALIFIER_TYPE_OS);
+							comp = attestation_state->create_component(
+											attestation_state, comp_name,
+											0, this->pts_db);
+							if (!comp)
+							{
+								comp_name->log(comp_name, "unregistered ");
+								comp_name->destroy(comp_name);
+							}
+						}
+
+						/* do TPM TRUSTED BOOT measurements */
+						if (strchr(workitem->get_arg_str(workitem), 'T'))
+						{
+							comp_name = pts_comp_func_name_create(PEN_ITA,
+											 PTS_ITA_COMP_FUNC_NAME_TBOOT,
+											PTS_ITA_QUALIFIER_FLAG_KERNEL |
+											PTS_ITA_QUALIFIER_TYPE_TRUSTED);
+							comp = attestation_state->create_component(
+											attestation_state, comp_name,
+											0, this->pts_db);
+							if (!comp)
+							{
+								comp_name->log(comp_name, "unregistered ");
+								comp_name->destroy(comp_name);
+							}
+						}
+						attestation_state->set_handshake_state(attestation_state,
+											IMV_ATTESTATION_STATE_NONCE_REQ);
+						continue;
+					}
+					default:
+						continue;
+				}
+
+				/* initiate file and directory measurements */
+				pathname = this->pts_db->get_pathname(this->pts_db, is_dir,
+											workitem->get_arg_int(workitem));
+				if (!pathname)
+				{
+					continue;
+				}
+				workitem->set_imv_id(workitem, imv_id);
+				no_workitems = FALSE;
+
+				if (workitem->get_type(workitem) == IMV_WORKITEM_FILE_META)
+				{
+					TNC_IMV_Action_Recommendation rec;
+					TNC_IMV_Evaluation_Result eval;
+					char result_str[BUF_LEN];
+
+					DBG2(DBG_IMV, "IMV %d requests metadata for %s '%s'",
+						 imv_id, is_dir ? "directory" : "file", pathname);
+
+					/* currently just fire and forget metadata requests */
+					attr = tcg_pts_attr_req_file_meta_create(is_dir,
+												delimiter, pathname);
+					snprintf(result_str, BUF_LEN, "%s metadata requested",
+							 is_dir ? "directory" : "file");
+					eval = TNC_IMV_EVALUATION_RESULT_COMPLIANT;
+					session->remove_workitem(session, enumerator);
+					rec = workitem->set_result(workitem, result_str, eval);
+					state->update_recommendation(state, rec, eval);
+					imcv_db->finalize_workitem(imcv_db, workitem);
+					workitem->destroy(workitem);
+				}
+				else
+				{
+					/* use lower 16 bits of the workitem ID as request ID */
+					request_id = workitem->get_id(workitem) & 0xffff;
+
+					DBG2(DBG_IMV, "IMV %d requests measurement %d for %s '%s'",
+						 imv_id, request_id, is_dir ? "directory" : "file",
+						 pathname);
+					attr = tcg_pts_attr_req_file_meas_create(is_dir, request_id,
+												delimiter, pathname);
+				}
+				free(pathname);
+				attr->set_noskip_flag(attr, TRUE);
+				out_msg->add_attribute(out_msg, attr);
+			}
+			enumerator->destroy(enumerator);
+
+			/* sent all file and directory measurement and metadata requests */
+			state->set_action_flags(state, IMV_ATTESTATION_FILE_MEAS);
+
+			if (no_workitems)
+			{
+				DBG2(DBG_IMV, "IMV %d has no workitems - "
+							  "no evaluation requested", imv_id);
+				state->set_recommendation(state,
+								TNC_IMV_ACTION_RECOMMENDATION_ALLOW,
+								TNC_IMV_EVALUATION_RESULT_DONT_KNOW);
+			}
+		}
+	}
+
+	/* check the IMV state for the next PA-TNC attributes to send */
+	enumerator = session->create_workitem_enumerator(session);
+	while (enumerator->enumerate(enumerator, &workitem))
+	{
+		if (workitem->get_type(workitem) == IMV_WORKITEM_TPM_ATTEST)
+		{
+			if (!imv_attestation_build(out_msg, state,
+									   this->supported_dh_groups, this->pts_db))
+			{
+				imv_reason_string_t *reason_string;
+				chunk_t result;
+				char *result_str;
+
+				reason_string = imv_reason_string_create("en", ", ");
+				attestation_state->add_comp_evid_reasons(attestation_state,
+													 reason_string);
+				result = reason_string->get_encoding(reason_string);
+				result_str = strndup(result.ptr, result.len);
+				reason_string->destroy(reason_string);
+
+				eval = TNC_IMV_EVALUATION_RESULT_ERROR;
+				session->remove_workitem(session, enumerator);
+				rec = workitem->set_result(workitem, result_str, eval);
+				state->update_recommendation(state, rec, eval);
+				imcv_db->finalize_workitem(imcv_db, workitem);
+			}
+			break;
+		}
+	}
+	enumerator->destroy(enumerator);
+
+	/* finalized all workitems? */
+	if (session->get_policy_started(session) &&
+		session->get_workitem_count(session, imv_id) == 0 &&
+		attestation_state->get_handshake_state(attestation_state) ==
+			IMV_ATTESTATION_STATE_END)
+	{
+		result = out_msg->send_assessment(out_msg);
+		out_msg->destroy(out_msg);
+		state->set_action_flags(state, IMV_ATTESTATION_REC);
+
+		if (result != TNC_RESULT_SUCCESS)
+		{
+			return result;
+		}
+		return this->agent->provide_recommendation(this->agent, state);
+	}
+
+	/* send non-empty PA-TNC message with excl flag not set */
+	if (out_msg->get_attribute_count(out_msg))
+	{
+		result = out_msg->send(out_msg, FALSE);
+	}
+	out_msg->destroy(out_msg);
+
+	return result;
+}
+
+METHOD(imv_agent_if_t, solicit_recommendation, TNC_Result,
+	private_imv_attestation_agent_t *this, TNC_ConnectionID id)
+{
+	TNC_IMVID imv_id;
+	imv_state_t *state;
+	imv_attestation_state_t *attestation_state;
+	imv_session_t *session;
+
+	if (!this->agent->get_state(this->agent, id, &state))
+	{
+		return TNC_RESULT_FATAL;
+	}
+	attestation_state = (imv_attestation_state_t*)state;
+	session = state->get_session(state);
+	imv_id = this->agent->get_id(this->agent);
+
+	if (imcv_db)
+	{
+		TNC_IMV_Evaluation_Result eval;
+		TNC_IMV_Action_Recommendation rec;
+		imv_workitem_t *workitem;
+		enumerator_t *enumerator;
+		int pending_file_meas = 0;
+		char *result_str;
+		chunk_t result_buf;
+		bio_writer_t *result;
+
+		enumerator = session->create_workitem_enumerator(session);
+		if (enumerator)
+		{
+			while (enumerator->enumerate(enumerator, &workitem))
+			{
+				if (workitem->get_imv_id(workitem) != imv_id)
+				{
+					continue;
+				}
+				result = bio_writer_create(128);
+
+				switch (workitem->get_type(workitem))
+				{
+					case IMV_WORKITEM_FILE_REF_MEAS:
+					case IMV_WORKITEM_FILE_MEAS:
+					case IMV_WORKITEM_DIR_REF_MEAS:
+					case IMV_WORKITEM_DIR_MEAS:
+						result_str = "pending file measurements";
+						pending_file_meas++;
+						break;
+					case IMV_WORKITEM_TPM_ATTEST:
+						attestation_state->finalize_components(attestation_state,
+															   result);
+						result->write_data(result,
+								chunk_from_str("; pending component evidence"));
+						result->write_uint8(result, '\0');
+						result_buf = result->get_buf(result);
+						result_str = result_buf.ptr;
+						break;
+					default:
+						result->destroy(result);
+						continue;
+				}
+				session->remove_workitem(session, enumerator);
+				eval = TNC_IMV_EVALUATION_RESULT_ERROR;
+				rec = workitem->set_result(workitem, result_str, eval);
+				state->update_recommendation(state, rec, eval);
+				imcv_db->finalize_workitem(imcv_db, workitem);
+				workitem->destroy(workitem);
+				result->destroy(result);
+			}
+			enumerator->destroy(enumerator);
+
+			if (pending_file_meas)
+			{
+				DBG1(DBG_IMV, "failure due to %d pending file measurements",
+							   pending_file_meas);
+				attestation_state->set_measurement_error(attestation_state,
+							   IMV_ATTESTATION_ERROR_FILE_MEAS_PEND);
+			}
+		}
+	}
+	return this->agent->provide_recommendation(this->agent, state);
+}
+
+METHOD(imv_agent_if_t, destroy, void,
+	private_imv_attestation_agent_t *this)
+{
+	if (this->pts_creds)
+	{
+		this->pts_credmgr->remove_set(this->pts_credmgr,
+						 			  this->pts_creds->get_set(this->pts_creds));
+		this->pts_creds->destroy(this->pts_creds);
+	}
+	DESTROY_IF(this->pts_db);
+	DESTROY_IF(this->pts_credmgr);
+	DESTROY_IF(this->agent);
+	free(this);
+}
+
+/**
+ * Described in header.
+ */
+imv_agent_if_t *imv_attestation_agent_create(const char *name, TNC_IMVID id,
+										 TNC_Version *actual_version)
+{
+	private_imv_attestation_agent_t *this;
+	imv_agent_t *agent;
+	char *hash_alg, *dh_group, *cadir;
+	bool mandatory_dh_groups;
+
+	agent = imv_agent_create(name, msg_types, countof(msg_types), id,
+							 actual_version);
+	if (!agent)
+	{
+		return NULL;
+	}
+
+	hash_alg = lib->settings->get_str(lib->settings,
+				"%s.plugins.imv-attestation.hash_algorithm", "sha256", lib->ns);
+	dh_group = lib->settings->get_str(lib->settings,
+				"%s.plugins.imv-attestation.dh_group", "ecp256", lib->ns);
+	mandatory_dh_groups = lib->settings->get_bool(lib->settings,
+				"%s.plugins.imv-attestation.mandatory_dh_groups", TRUE, lib->ns);
+	cadir = lib->settings->get_str(lib->settings,
+				"%s.plugins.imv-attestation.cadir", NULL, lib->ns);
+
+	INIT(this,
+		.public = {
+			.bind_functions = _bind_functions,
+			.notify_connection_change = _notify_connection_change,
+			.receive_message = _receive_message,
+			.receive_message_long = _receive_message_long,
+			.batch_ending = _batch_ending,
+			.solicit_recommendation = _solicit_recommendation,
+			.destroy = _destroy,
+		},
+		.agent = agent,
+		.supported_algorithms = PTS_MEAS_ALGO_NONE,
+		.supported_dh_groups = PTS_DH_GROUP_NONE,
+		.pts_credmgr = credential_manager_create(),
+		.pts_creds = pts_creds_create(cadir),
+		.pts_db = pts_database_create(imcv_db),
+	);
+
+	if (!pts_meas_algo_probe(&this->supported_algorithms) ||
+		!pts_dh_group_probe(&this->supported_dh_groups, mandatory_dh_groups) ||
+		!pts_meas_algo_update(hash_alg, &this->supported_algorithms) ||
+		!pts_dh_group_update(dh_group, &this->supported_dh_groups))
+	{
+		destroy(this);
+		return NULL;
+	}
+
+	if (this->pts_creds)
+	{
+		this->pts_credmgr->add_set(this->pts_credmgr,
+								   this->pts_creds->get_set(this->pts_creds));
+	}
+
+	return &this->public;
+}