Added TCG-SWID error handling

src/libpts/Makefile.am

@@ -35,6 +35,7 @@ libpts_la_SOURCES = \
 	pts/components/ita/ita_comp_tboot.h pts/components/ita/ita_comp_tboot.c \
 	pts/components/ita/ita_comp_tgrub.h pts/components/ita/ita_comp_tgrub.c \
 	pts/components/tcg/tcg_comp_func_name.h pts/components/tcg/tcg_comp_func_name.c \
+	swid/swid_error.h swid/swid_error.c \
 	swid/swid_tag.h swid/swid_tag.c \
 	swid/swid_tag_id.h swid/swid_tag_id.c \
 	tcg/tcg_attr.h tcg/tcg_attr.c \

src/libpts/plugins/imc_swid/imc_swid.c

@@ -18,6 +18,7 @@
 #include "libpts.h"
 #include "swid/swid_tag.h"
 #include "swid/swid_tag_id.h"
+#include "swid/swid_error.h"
 #include "tcg/swid/tcg_swid_attr_req.h"
 #include "tcg/swid/tcg_swid_attr_tag_inv.h"
 #include "tcg/swid/tcg_swid_attr_tag_id_inv.h"
@@ -199,6 +200,14 @@ static TNC_Result receive_message(imc_state_t *state, imc_msg_t *in_msg)
 		request_id = attr_req->get_request_id(attr_req);
 		eid_epoch = swid_state->get_eid_epoch(swid_state);
 
+		if (flags & (TCG_SWID_ATTR_REQ_FLAG_S | TCG_SWID_ATTR_REQ_FLAG_C))
+		{
+			attr = swid_error_create(TCG_SWID_SUBSCRIPTION_DENIED, request_id,
+									 0, "no subscription available yet");
+			out_msg->add_attribute(out_msg, attr);
+			break;
+		}
+
 		if (flags & TCG_SWID_ATTR_REQ_FLAG_R)
 		{
 			swid_tag_id_t *tag_id;

src/libpts/plugins/imv_swid/imv_swid_agent.c

@@ -17,11 +17,13 @@
 #include "imv_swid_state.h"
 
 #include "libpts.h"
+#include "swid/swid_error.h"
 #include "tcg/swid/tcg_swid_attr_req.h"
 #include "tcg/swid/tcg_swid_attr_tag_inv.h"
 #include "tcg/swid/tcg_swid_attr_tag_id_inv.h"
 
 #include <imcv.h>
+#include <ietf/ietf_attr_pa_tnc_error.h>
 #include <imv/imv_agent.h>
 #include <imv/imv_msg.h>
 
@@ -30,6 +32,7 @@
 
 #include <pen/pen.h>
 #include <utils/debug.h>
+#include <bio/bio_reader.h>
 
 typedef struct private_imv_swid_agent_t private_imv_swid_agent_t;
 
@@ -89,7 +92,6 @@ static TNC_Result receive_msg(private_imv_swid_agent_t *this,
 	imv_session_t *session;
 	enumerator_t *enumerator;
 	pa_tnc_attr_t *attr;
-	pen_type_t type;
 	TNC_Result result;
 	bool fatal_error = FALSE;
 
@@ -108,6 +110,7 @@ static TNC_Result receive_msg(private_imv_swid_agent_t *this,
 	{
 		TNC_IMV_Evaluation_Result eval;
 		TNC_IMV_Action_Recommendation rec;
+		pen_type_t type;
 		u_int32_t request_id, last_eid, eid_epoch;
 		int tag_count = 0;
 		char result_str[BUF_LEN], *tag_item;
@@ -116,10 +119,56 @@ static TNC_Result receive_msg(private_imv_swid_agent_t *this,
 		
 		type = attr->get_type(attr);
 
-		if (type.vendor_id != PEN_TCG)
+		if (type.vendor_id == PEN_IETF && type.type == IETF_ATTR_PA_TNC_ERROR)
+		{
+			ietf_attr_pa_tnc_error_t *error_attr;
+			pen_type_t error_code;
+			chunk_t msg_info, description;
+			bio_reader_t *reader;
+			u_int32_t request_id = 0, max_attr_size;
+			bool success;
+
+			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)
+			{
+				fatal_error = TRUE;
+				msg_info = error_attr->get_msg_info(error_attr);
+				reader = bio_reader_create(msg_info);
+				success = reader->read_uint32(reader, &request_id);
+
+				DBG1(DBG_IMV, "received TCG error '%N' for request %d",
+					 swid_error_code_names, error_code.type, request_id);
+				if (!success)
+				{
+					reader->destroy(reader);
+					continue;
+				}
+				if (error_code.type == TCG_SWID_RESPONSE_TOO_LARGE)
+				{
+					if (!reader->read_uint32(reader, &max_attr_size))
+					{
+						reader->destroy(reader);
+						continue;
+					}
+					DBG1(DBG_IMV, "  maximum PA-TNC attribute size is %u bytes",
+						max_attr_size);
+				}
+				description = reader->peek(reader);
+				if (description.len)
+				{ 
+					DBG1(DBG_IMV, "  description: %.*s", description.len,
+														 description.ptr);
+				}
+				reader->destroy(reader);
+			}
+		}
+		else if (type.vendor_id != PEN_TCG)
 		{
 			continue;
 		}
+
 		switch (type.type)
 		{
 			case TCG_SWID_TAG_ID_INVENTORY:

src/libpts/swid/swid_error.c

@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2011 Sansar Choinyambuu
+ * 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.
+ */
+
+#include "swid_error.h"
+
+#include <bio/bio_writer.h>
+#include <ietf/ietf_attr_pa_tnc_error.h>
+
+ENUM(swid_error_code_names, TCG_SWID_ERROR, TCG_SWID_RESPONSE_TOO_LARGE,
+	"SWID Error",
+	"SWID Subscription Denied",
+	"SWID Response Too Large"
+);
+
+/**
+ * Described in header.
+ */
+pa_tnc_attr_t* swid_error_create(swid_error_code_t code, u_int32_t request_id,
+								 u_int32_t max_attr_size, char *description)
+{
+	bio_writer_t *writer;
+	chunk_t msg_info;
+	pa_tnc_attr_t *attr;
+	pen_type_t error_code;
+
+	error_code = pen_type_create( PEN_TCG, code);
+	writer = bio_writer_create(4);
+	writer->write_uint32(writer, request_id);
+	if (code == TCG_SWID_RESPONSE_TOO_LARGE)
+	{
+		writer->write_uint16(writer, max_attr_size);
+	}
+	if (description)
+	{
+		writer->write_data(writer, chunk_from_str(description));
+	}
+	msg_info = writer->get_buf(writer);
+	attr = ietf_attr_pa_tnc_error_create(error_code, msg_info);
+	writer->destroy(writer);
+
+	return attr;
+}
+

src/libpts/swid/swid_error.h

@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+/**
+ * @defgroup swid_error swid_error
+ * @{ @ingroup swid
+ */
+
+#ifndef SWID_ERROR_H_
+#define SWID_ERROR_H_
+
+typedef enum swid_error_code_t swid_error_code_t;
+
+#include "pa_tnc/pa_tnc_attr.h"
+
+#include <library.h>
+
+
+/**
+ * SWID Error Codes
+ * see section 3.14.2 of PTS Protocol: Binding to TNC IF-M Specification
+ */
+enum swid_error_code_t {
+	TCG_SWID_ERROR = 		        0x20,
+	TCG_SWID_SUBSCRIPTION_DENIED =  0x21,
+	TCG_SWID_RESPONSE_TOO_LARGE =   0x22
+};
+
+/**
+ * enum name for swid_error_code_t.
+ */
+extern enum_name_t *swid_error_code_names;
+
+/**
+ * Creates a SWID Error Attribute
+ * see section 4.12 of TNC SWID Message and Attributes for IF-M
+ *
+ * @param code				SWID error code
+ * @param request			SWID request ID
+ * @param max_attr_size		Maximum IF-M attribute size (if applicable)
+ * @param description		Optional description string or NULL
+ */
+pa_tnc_attr_t* swid_error_create(swid_error_code_t code, u_int32_t request,
+								 u_int32_t max_attr_size, char *description);
+
+#endif /** SWID_ERROR_H_ @}*/

src/libpts/tcg/swid/tcg_swid_attr_req.c

@@ -175,6 +175,12 @@ METHOD(pa_tnc_attr_t, process, status_t,
 	reader->read_uint24(reader, &tag_id_count);
 	reader->read_uint32(reader, &this->request_id);
 	reader->read_uint32(reader, &this->earliest_eid);
+
+	if (this->request_id == 0)
+	{
+		*offset = 4;
+		return FAILED;
+	}
 	*offset = SWID_REQ_SIZE;
 
 	this->flags &= SWID_REQ_RESERVED_MASK;