1 files changed, 261 insertions, 0 deletions
diff --git a/src/libimcv/seg/seg_env.c b/src/libimcv/seg/seg_env.c
new file mode 100644
index 000000000..1f4cfc53f
--- /dev/null
+++ b/src/libimcv/seg/seg_env.c
@@ -0,0 +1,261 @@
+/*
+ * Copyright (C) 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.
+ */
+
+#include "seg_env.h"
+
+#include "imcv.h"
+#include "pa_tnc/pa_tnc_msg.h"
+
+#include <utils/debug.h>
+#include <bio/bio_reader.h>
+#include <bio/bio_writer.h>
+
+#include <tcg/seg/tcg_seg_attr_seg_env.h>
+
+#define BASE_ATTR_ID_PREFIX	0xFF
+
+typedef struct private_seg_env_t private_seg_env_t;
+
+/**
+ * Private data of a seg_env_t object.
+ */
+struct private_seg_env_t {
+
+	/**
+	 * Public seg_env_t interface.
+	 */
+	seg_env_t public;
+
+	/**
+	 * Base Attribute ID
+	 */
+	uint32_t base_attr_id;
+
+	/**
+	 * Base Attribute
+	 */
+	pa_tnc_attr_t *base_attr;
+
+	/**
+	 * Maximum PA-TNC attribute segment size
+	 */
+	uint32_t max_seg_size;
+
+	/**
+	 * TRUE if attribute is assembled from data
+	 */
+	bool from_data;
+
+	/**
+	 * Remaining attribute data to be sent or received data being accumulated
+	 */
+	chunk_t data;
+
+};
+
+METHOD(seg_env_t, get_base_attr_id, uint32_t,
+	private_seg_env_t *this)
+{
+	return this->base_attr_id;
+}
+
+METHOD(seg_env_t, get_base_attr, pa_tnc_attr_t*,
+	private_seg_env_t *this, pa_tnc_attr_t** error)
+{
+	*error = NULL;
+
+	if (!this->base_attr)
+	{
+		bio_writer_t *writer;
+		bio_reader_t *reader;
+		chunk_t msg_info;
+		uint32_t offset = 0;
+
+		writer = bio_writer_create(8);
+		writer->write_uint8 (writer, PA_TNC_VERSION);
+		writer->write_uint24(writer, PA_TNC_RESERVED);
+		writer->write_uint8 (writer, BASE_ATTR_ID_PREFIX);
+		writer->write_uint24(writer, this->base_attr_id);
+		msg_info = writer->extract_buf(writer);
+		writer->destroy(writer);
+
+		reader = bio_reader_create(this->data);
+		this->base_attr = imcv_pa_tnc_attributes->create(imcv_pa_tnc_attributes,
+										reader, &offset, msg_info, error);
+		chunk_free(&msg_info);
+		reader->destroy(reader);
+	}
+		
+	return this->base_attr ? this->base_attr->get_ref(this->base_attr) : NULL;
+}
+
+METHOD(seg_env_t, first_segment, pa_tnc_attr_t*,
+	private_seg_env_t *this)
+{
+	pa_tnc_attr_t *seg_env_attr;
+	bio_writer_t *writer;
+	pen_type_t type;
+	chunk_t segment_data, value;
+	uint8_t flags, seg_env_flags;
+
+	/* get components of base attribute header and data */
+	flags = this->base_attr->get_noskip_flag(this->base_attr) ?
+				PA_TNC_ATTR_FLAG_NOSKIP : PA_TNC_ATTR_FLAG_NONE;
+	type = this->base_attr->get_type(this->base_attr);
+
+	/* attribute data going into the first segment */
+	segment_data = this->data;
+	segment_data.len = this->max_seg_size - PA_TNC_ATTR_HEADER_SIZE;
+
+	/* build encoding of the base attribute header and first segment data */
+	writer = bio_writer_create(this->max_seg_size);
+	writer->write_uint8 (writer, flags);
+	writer->write_uint24(writer, type.vendor_id);
+	writer->write_uint32(writer, type.type);
+	writer->write_uint32(writer, PA_TNC_ATTR_HEADER_SIZE + this->data.len);
+	writer->write_data  (writer, segment_data);
+	value = writer->extract_buf(writer);
+	writer->destroy(writer);
+	this->data = chunk_skip(this->data, segment_data.len);
+
+	DBG2(DBG_TNC, "creating first segment for base attribute ID %d (%d bytes)",
+		 this->base_attr_id, this->max_seg_size);
+
+	seg_env_flags = SEG_ENV_FLAG_START | SEG_ENV_FLAG_MORE;
+	seg_env_attr = tcg_seg_attr_seg_env_create(value, seg_env_flags,
+											   this->base_attr_id);
+	chunk_free(&value);
+
+	return seg_env_attr;
+}
+
+METHOD(seg_env_t, next_segment, pa_tnc_attr_t*,
+	private_seg_env_t *this, bool *last)
+{
+	pa_tnc_attr_t *seg_env_attr;
+	chunk_t segment_data;
+	uint8_t seg_env_flags;
+	bool is_last_segment;
+
+	if (this->data.len == 0)
+	{
+		/* no more attribute data to segment available */
+		return NULL;
+	}
+
+	/* attribute data going into the next segment */
+	segment_data = this->data;
+	segment_data.len = min(this->max_seg_size, this->data.len);
+	this->data = chunk_skip(this->data, segment_data.len);
+
+	is_last_segment = (this->data.len == 0);
+	if (last)
+	{
+		*last = is_last_segment;
+	}
+	DBG2(DBG_TNC, "creating %s segment for base attribute ID %d (%d bytes)",
+				   is_last_segment ? "last" : "next", this->base_attr_id,
+				   segment_data.len);
+
+	seg_env_flags = is_last_segment ? SEG_ENV_FLAG_NONE : SEG_ENV_FLAG_MORE;
+	seg_env_attr = tcg_seg_attr_seg_env_create(segment_data, seg_env_flags,
+											   this->base_attr_id);
+
+	return seg_env_attr;
+}
+
+METHOD(seg_env_t, add_segment, void,
+	private_seg_env_t *this, chunk_t segment_data)
+{
+	this->data = chunk_cat("mc", this->data, segment_data);
+}
+
+METHOD(seg_env_t, destroy, void,
+	private_seg_env_t *this)
+{
+	if (this->from_data)
+	{
+		chunk_free(&this->data);
+	}
+	DESTROY_IF(this->base_attr);
+	free(this);
+}
+
+/**
+ * See header
+ */
+seg_env_t *seg_env_create(uint32_t base_attr_id, pa_tnc_attr_t *base_attr,
+						  uint32_t max_seg_size)
+{
+	private_seg_env_t *this;
+	chunk_t value;
+
+	base_attr->build(base_attr);
+	value = base_attr->get_value(base_attr);
+
+	/**
+	 * The PA-TNC attribute header must not be segmented and
+	 * there must be at least a first and one next segment
+	 */
+	if (max_seg_size <  PA_TNC_ATTR_HEADER_SIZE ||
+		max_seg_size >= PA_TNC_ATTR_HEADER_SIZE + value.len)
+	{
+		return NULL;
+	}
+
+	INIT(this,
+		.public = {
+			.get_base_attr_id = _get_base_attr_id,
+			.get_base_attr = _get_base_attr,
+			.first_segment = _first_segment,
+			.next_segment = _next_segment,
+			.add_segment = _add_segment,
+			.destroy = _destroy,
+		},
+		.base_attr_id = base_attr_id,
+		.base_attr = base_attr->get_ref(base_attr),
+		.max_seg_size = max_seg_size,
+		.data = base_attr->get_value(base_attr),
+	);
+
+	return &this->public;
+}
+
+/**
+ * See header
+ */
+seg_env_t *seg_env_create_from_data(uint32_t base_attr_id, chunk_t data,
+									uint32_t max_seg_size)
+{
+	private_seg_env_t *this;
+
+	INIT(this,
+		.public = {
+			.get_base_attr_id = _get_base_attr_id,
+			.get_base_attr = _get_base_attr,
+			.first_segment = _first_segment,
+			.next_segment = _next_segment,
+			.add_segment = _add_segment,
+			.destroy = _destroy,
+		},
+		.base_attr_id = base_attr_id,
+		.max_seg_size = max_seg_size,
+		.data = chunk_clone(data),
+		.from_data = TRUE,
+	);
+
+	return &this->public;
+}
+