From: Andreas Steffen <andreas.steffen@strongswan.org>
Date: Mon, 26 May 2014 07:36:31 +0000 (+0200)
Subject: Split TCG SWID Request attribute into chunks if needed
X-Git-Tag: 5.2.0dr5~17
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=34cd3e102ee2b49ad54ecb84696284b6592d91f7;p=thirdparty%2Fstrongswan.git

Split TCG SWID Request attribute into chunks if needed
---

diff --git a/src/libpts/plugins/imc_swid/imc_swid.c b/src/libpts/plugins/imc_swid/imc_swid.c
index 4fad431c19..477b3b1f42 100644
--- a/src/libpts/plugins/imc_swid/imc_swid.c
+++ b/src/libpts/plugins/imc_swid/imc_swid.c
@@ -178,7 +178,7 @@ static bool add_swid_inventory(imc_state_t *state, imc_msg_t *msg,
 	eid_epoch = swid_state->get_eid_epoch(swid_state);
 
 	/**
-	 * Compute the maximum TCG Tag [ID] Inventory attribute size
+	 * Compute the maximum TCG SWID Tag [ID] Inventory attribute size
 	 * leaving space for an additional ITA Angel attribute
 	 */
 	max_attr_size = state->get_max_msg_len(state) -
diff --git a/src/libpts/plugins/imv_swid/imv_swid_agent.c b/src/libpts/plugins/imv_swid/imv_swid_agent.c
index f5a343af21..450bf9e381 100644
--- a/src/libpts/plugins/imv_swid/imv_swid_agent.c
+++ b/src/libpts/plugins/imv_swid/imv_swid_agent.c
@@ -467,6 +467,7 @@ METHOD(imv_agent_if_t, batch_ending, TNC_Result,
 		char result_str[BUF_LEN], *error_str = "", *command;
 		char *target, *separator;
 		int tag_id_count, tag_count, i;
+		size_t max_attr_size, attr_size, entry_size;
 		chunk_t tag_creator, unique_sw_id;
 		json_object *jrequest, *jresponse, *jvalue;
 		tcg_swid_attr_req_t *cast_attr;
@@ -535,9 +536,15 @@ METHOD(imv_agent_if_t, batch_ending, TNC_Result,
 					json_object_put(jresponse);
 					break;
 				}
+
+				/* Compute the maximum TCG SWID Request attribute size */
+				max_attr_size = state->get_max_msg_len(state) -
+								PA_TNC_HEADER_SIZE;
+
+				/* Create the [first] TCG SWID Request attribute */
+				attr_size = PA_TNC_ATTR_HEADER_SIZE + TCG_SWID_REQ_MIN_SIZE;			
 				attr = tcg_swid_attr_req_create(TCG_SWID_ATTR_REQ_FLAG_NONE,
 								swid_state->get_request_id(swid_state), 0);
-				cast_attr = (tcg_swid_attr_req_t*)attr;
 
 				tag_id_count = json_object_array_length(jresponse);
 				DBG1(DBG_IMV, "%d SWID tag targets", tag_id_count);
@@ -569,6 +576,19 @@ METHOD(imv_agent_if_t, batch_ending, TNC_Result,
 												tag_creator.len - 1);
 					tag_id = swid_tag_id_create(tag_creator, unique_sw_id,
 												chunk_empty);
+					entry_size = 2 + tag_creator.len + 2 + unique_sw_id.len;
+
+					/* Have we reached the maximum attribute size? */
+					if (attr_size + entry_size > max_attr_size)
+					{
+						out_msg->add_attribute(out_msg, attr);
+						attr_size = PA_TNC_ATTR_HEADER_SIZE + 
+									TCG_SWID_REQ_MIN_SIZE;			
+						attr = tcg_swid_attr_req_create(
+									TCG_SWID_ATTR_REQ_FLAG_NONE,
+									swid_state->get_request_id(swid_state), 0);
+					}
+					cast_attr = (tcg_swid_attr_req_t*)attr;
 					cast_attr->add_target(cast_attr, tag_id);
 				}
 				json_object_put(jresponse);
diff --git a/src/libpts/tcg/swid/tcg_swid_attr_req.c b/src/libpts/tcg/swid/tcg_swid_attr_req.c
index b8e7962c1e..c403d06f92 100644
--- a/src/libpts/tcg/swid/tcg_swid_attr_req.c
+++ b/src/libpts/tcg/swid/tcg_swid_attr_req.c
@@ -44,7 +44,6 @@ typedef struct private_tcg_swid_attr_req_t private_tcg_swid_attr_req_t;
  *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  */
 
-#define SWID_REQ_SIZE					12
 #define SWID_REQ_RESERVED_MASK			0x03
 
 /**
@@ -135,7 +134,7 @@ METHOD(pa_tnc_attr_t, build, void,
 		return;
 	}
 
-	writer = bio_writer_create(SWID_REQ_SIZE);
+	writer = bio_writer_create(TCG_SWID_REQ_MIN_SIZE);
 	writer->write_uint8 (writer, this->flags);
 	writer->write_uint24(writer, this->targets->get_count(this->targets));
 	writer->write_uint32(writer, this->request_id);
@@ -163,7 +162,7 @@ METHOD(pa_tnc_attr_t, process, status_t,
 	chunk_t tag_creator, unique_sw_id;
 	swid_tag_id_t *tag_id;
 
-	if (this->value.len < SWID_REQ_SIZE)
+	if (this->value.len < TCG_SWID_REQ_MIN_SIZE)
 	{
 		DBG1(DBG_TNC, "insufficient data for SWID Request");
 		*offset = 0;
@@ -181,7 +180,7 @@ METHOD(pa_tnc_attr_t, process, status_t,
 		*offset = 4;
 		return FAILED;
 	}
-	*offset = SWID_REQ_SIZE;
+	*offset = TCG_SWID_REQ_MIN_SIZE;
 
 	this->flags &= SWID_REQ_RESERVED_MASK;
 
diff --git a/src/libpts/tcg/swid/tcg_swid_attr_req.h b/src/libpts/tcg/swid/tcg_swid_attr_req.h
index 851b68d3b2..59b597d844 100644
--- a/src/libpts/tcg/swid/tcg_swid_attr_req.h
+++ b/src/libpts/tcg/swid/tcg_swid_attr_req.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2013 Andreas Steffen
+ * Copyright (C) 2013-2014 Andreas Steffen
  * HSR Hochschule fuer Technik Rapperswil
  *
  * This program is free software; you can redistribute it and/or modify it
@@ -21,6 +21,8 @@
 #ifndef TCG_SWID_ATTR_REQ_H_
 #define TCG_SWID_ATTR_REQ_H_
 
+#define TCG_SWID_REQ_MIN_SIZE	12
+
 typedef struct tcg_swid_attr_req_t tcg_swid_attr_req_t;
 typedef enum tcg_swid_attr_req_flag_t tcg_swid_attr_req_flag_t;