1 files changed, 427 insertions, 0 deletions

diff --git a/src/libimcv/pa_tnc/pa_tnc_msg.c b/src/libimcv/pa_tnc/pa_tnc_msg.c
new file mode 100644
index 000000000..b5df0a5b5
--- /dev/null
+++ b/src/libimcv/pa_tnc/pa_tnc_msg.c
@@ -0,0 +1,427 @@
+/*
+ * Copyright (C) 2011 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 "imcv.h"
+#include "pa_tnc_msg.h"
+#include "ietf/ietf_attr_pa_tnc_error.h"
+
+#include <bio/bio_writer.h>
+#include <bio/bio_reader.h>
+#include <utils/linked_list.h>
+#include <pen/pen.h>
+#include <debug.h>
+
+
+typedef struct private_pa_tnc_msg_t private_pa_tnc_msg_t;
+
+/**
+ *   PA-TNC message header
+ *
+ *                        1                   2                   3
+ *   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  |    Version    |                    Reserved                   |
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  |                       Message Identifier                      |
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+
+#define PA_TNC_HEADER_SIZE	8
+#define PA_TNC_RESERVED		0x000000
+
+/**
+ *  PA-TNC attribute 
+ *
+ *                       1                   2                   3
+ *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  |     Flags     |          PA-TNC Attribute Vendor ID           |
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  |                     PA-TNC Attribute Type                     |
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  |                    PA-TNC Attribute Length                    |
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  |                 Attribute Value (Variable Length)             |
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+
+#define PA_TNC_ATTR_FLAG_NONE			0x00
+#define PA_TNC_ATTR_FLAG_NOSKIP			(1<<7)
+#define PA_TNC_ATTR_HEADER_SIZE			12
+#define PA_TNC_ATTR_INFO_SIZE			8
+
+/**
+ * Private data of a pa_tnc_msg_t object.
+ *
+ */
+struct private_pa_tnc_msg_t {
+
+	/**
+	 * Public pa_tnc_msg_t interface.
+	 */
+	pa_tnc_msg_t public;
+
+	/**
+	 * List of PA-TNC attributes
+	 */
+	linked_list_t *attributes;
+
+	/**
+	 * linked list of PA-TNC error messages
+	 */
+	linked_list_t *errors;
+
+	/**
+	 * Message identifier
+	 */
+	u_int32_t identifier;
+
+	/**
+	 * Encoded message
+	 */
+	chunk_t encoding;
+};
+
+METHOD(pa_tnc_msg_t, get_encoding, chunk_t,
+	private_pa_tnc_msg_t *this)
+{
+	return this->encoding;
+}
+
+METHOD(pa_tnc_msg_t, add_attribute, void,
+	private_pa_tnc_msg_t *this, pa_tnc_attr_t *attr)
+{
+	this->attributes->insert_last(this->attributes, attr);
+}
+
+METHOD(pa_tnc_msg_t, build, void,
+	private_pa_tnc_msg_t *this)
+{
+	bio_writer_t *writer;
+	enumerator_t *enumerator;
+	pa_tnc_attr_t *attr;
+	enum_name_t *pa_attr_names;
+	pen_t vendor_id;
+	u_int32_t type;
+	u_int8_t flags;
+	chunk_t value;
+	rng_t *rng;
+
+	/* create a random message identifier */
+	rng = lib->crypto->create_rng(lib->crypto, RNG_WEAK);
+	rng->get_bytes(rng, sizeof(this->identifier), (u_int8_t*)&this->identifier);
+	rng->destroy(rng);
+	DBG2(DBG_TNC, "creating PA-TNC message with ID 0x%08x", this->identifier);
+
+	/* build message header */
+	writer = bio_writer_create(PA_TNC_HEADER_SIZE);
+	writer->write_uint8 (writer, PA_TNC_VERSION);
+	writer->write_uint24(writer, PA_TNC_RESERVED);
+	writer->write_uint32(writer, this->identifier);
+
+	/* build and append encoding of PA-TNC attributes */
+	enumerator = this->attributes->create_enumerator(this->attributes);
+	while (enumerator->enumerate(enumerator, &attr))
+	{
+		attr->build(attr);
+		vendor_id = attr->get_vendor_id(attr);
+		type = attr->get_type(attr);
+		value = attr->get_value(attr);
+		flags = attr->get_noskip_flag(attr) ? PA_TNC_ATTR_FLAG_NOSKIP :
+											  PA_TNC_ATTR_FLAG_NONE;
+
+		pa_attr_names = imcv_pa_tnc_attributes->get_names(imcv_pa_tnc_attributes,
+														  vendor_id);
+		if (pa_attr_names)
+		{
+			DBG2(DBG_TNC, "creating PA-TNC attribute type '%N/%N' "
+						  "0x%06x/0x%08x", pen_names, vendor_id,
+						   pa_attr_names, type, vendor_id, type);
+		}
+		else
+		{
+			DBG2(DBG_TNC, "creating PA-TNC attribute type '%N' "
+						  "0x%06x/0x%08x", pen_names, vendor_id,
+						   vendor_id, type);
+		}
+		DBG3(DBG_TNC, "%B", &value);
+
+		writer->write_uint8 (writer, flags);
+		writer->write_uint24(writer, vendor_id);
+		writer->write_uint32(writer, type);
+		writer->write_uint32(writer, PA_TNC_ATTR_HEADER_SIZE + value.len);
+		writer->write_data  (writer, value);
+	}
+	enumerator->destroy(enumerator);
+
+	free(this->encoding.ptr);
+	this->encoding = chunk_clone(writer->get_buf(writer));
+	writer->destroy(writer);
+}
+
+METHOD(pa_tnc_msg_t, process, status_t,
+	private_pa_tnc_msg_t *this)
+{
+	bio_reader_t *reader;
+	pa_tnc_attr_t *error;
+	u_int8_t version;
+	u_int32_t reserved, offset, attr_offset;
+
+	/* process message header */
+	if (this->encoding.len < PA_TNC_HEADER_SIZE)
+	{
+		DBG1(DBG_TNC, "%u bytes insufficient to parse PA-TNC message header",
+					   this->encoding.len);
+		return FAILED;
+	}
+	reader = bio_reader_create(this->encoding);
+	reader->read_uint8 (reader, &version);
+	reader->read_uint24(reader, &reserved);
+	reader->read_uint32(reader, &this->identifier);
+	DBG2(DBG_TNC, "processing PA-TNC message with ID 0x%08x", this->identifier);
+
+	if (version != PA_TNC_VERSION)
+	{
+		DBG1(DBG_TNC, "PA-TNC version %u not supported", version);
+		error = ietf_attr_pa_tnc_error_create(PEN_IETF,
+					PA_ERROR_VERSION_NOT_SUPPORTED, this->encoding);
+		goto err;
+	}
+	
+	/* offset of the first PA-TNC attribute in the PA-TNC message */
+	offset = PA_TNC_HEADER_SIZE;
+
+	/* pre-process PA-TNC attributes */
+	while (reader->remaining(reader) >= PA_TNC_ATTR_HEADER_SIZE)
+	{
+		pen_t vendor_id;
+		u_int8_t flags;
+		u_int32_t type, length;
+		chunk_t value, attr_info;
+		pa_tnc_attr_t *attr;
+		enum_name_t *pa_attr_names;
+		ietf_attr_pa_tnc_error_t *error_attr;
+
+		attr_info = reader->peek(reader);
+		attr_info.len = PA_TNC_ATTR_INFO_SIZE;
+		reader->read_uint8 (reader, &flags);
+		reader->read_uint24(reader, &vendor_id);
+		reader->read_uint32(reader, &type);
+		reader->read_uint32(reader, &length);
+
+		pa_attr_names = imcv_pa_tnc_attributes->get_names(imcv_pa_tnc_attributes,
+														  vendor_id);
+		if (pa_attr_names)
+		{
+			DBG2(DBG_TNC, "processing PA-TNC attribute type '%N/%N' "
+						  "0x%06x/0x%08x", pen_names, vendor_id,
+						   pa_attr_names, type, vendor_id, type);
+		}
+		else
+		{
+			DBG2(DBG_TNC, "processing PA-TNC attribute type '%N' "
+						  "0x%06x/0x%08x", pen_names, vendor_id,
+						   vendor_id, type);
+		}
+
+		if (length < PA_TNC_ATTR_HEADER_SIZE)
+		{
+			DBG1(DBG_TNC, "%u bytes too small for PA-TNC attribute length",
+						   length);
+			error = ietf_attr_pa_tnc_error_create_with_offset(PEN_IETF,
+						PA_ERROR_INVALID_PARAMETER, this->encoding,
+						offset + PA_TNC_ATTR_INFO_SIZE);
+			goto err;
+		}
+
+		if (!reader->read_data(reader, length - PA_TNC_ATTR_HEADER_SIZE, &value))
+		{
+			DBG1(DBG_TNC, "insufficient bytes for PA-TNC attribute value");
+			error = ietf_attr_pa_tnc_error_create_with_offset(PEN_IETF,
+						PA_ERROR_INVALID_PARAMETER, this->encoding,
+						offset + PA_TNC_ATTR_INFO_SIZE);
+			goto err; 
+		} 
+		DBG3(DBG_TNC, "%B", &value);
+
+		attr = imcv_pa_tnc_attributes->create(imcv_pa_tnc_attributes,
+											  vendor_id, type, value);
+		if (!attr)
+		{
+			if (flags & PA_TNC_ATTR_FLAG_NOSKIP)
+			{
+				DBG1(DBG_TNC, "unsupported PA-TNC attribute with NOSKIP flag");
+				error = ietf_attr_pa_tnc_error_create(PEN_IETF,
+							PA_ERROR_ATTR_TYPE_NOT_SUPPORTED, this->encoding);
+				error_attr = (ietf_attr_pa_tnc_error_t*)error;
+				error_attr->set_attr_info(error_attr, attr_info);
+				goto err;
+			}
+			else
+			{
+				DBG1(DBG_TNC, "skipping unsupported PA-TNC attribute");
+				offset += length;
+				continue;
+			}
+		}
+
+		if (attr->process(attr, &attr_offset) != SUCCESS)
+		{
+			attr->destroy(attr);
+			if (vendor_id == PEN_IETF && type == IETF_ATTR_PA_TNC_ERROR)
+			{
+				/* error while processing a PA-TNC error attribute - abort */
+				reader->destroy(reader);
+				return FAILED;
+			}
+			error = ietf_attr_pa_tnc_error_create_with_offset(PEN_IETF,
+						PA_ERROR_INVALID_PARAMETER, this->encoding,
+						offset + PA_TNC_ATTR_HEADER_SIZE + attr_offset);
+			goto err;
+		}
+		add_attribute(this, attr);
+		offset += length;
+	}
+
+	if (reader->remaining(reader) == 0)
+	{
+		reader->destroy(reader);
+		return SUCCESS;
+	}
+	DBG1(DBG_TNC, "insufficient bytes for PA-TNC attribute header");
+	error = ietf_attr_pa_tnc_error_create_with_offset(PEN_IETF,
+				PA_ERROR_INVALID_PARAMETER, this->encoding, offset);
+
+err:
+	reader->destroy(reader);
+	this->errors->insert_last(this->errors, error);
+	return VERIFY_ERROR;
+}
+
+METHOD(pa_tnc_msg_t, process_ietf_std_errors, bool,
+	private_pa_tnc_msg_t *this)
+{
+	enumerator_t *enumerator;
+	pa_tnc_attr_t *attr;
+	bool fatal_error = FALSE;
+
+	enumerator = this->attributes->create_enumerator(this->attributes);
+	while (enumerator->enumerate(enumerator, &attr))
+	{
+		if (attr->get_vendor_id(attr) == PEN_IETF &&
+			attr->get_type(attr) == IETF_ATTR_PA_TNC_ERROR)
+		{
+			ietf_attr_pa_tnc_error_t *error_attr;
+			pen_t error_vendor_id;
+			pa_tnc_error_code_t error_code;
+			chunk_t msg_info, attr_info;
+			u_int32_t offset;
+
+			error_attr = (ietf_attr_pa_tnc_error_t*)attr;
+			error_vendor_id = error_attr->get_vendor_id(error_attr);
+			error_code = error_attr->get_error_code(error_attr);
+			msg_info = error_attr->get_msg_info(error_attr);
+
+			/* skip errors from non-IETF namespaces */
+			if (error_vendor_id != PEN_IETF)
+			{
+				continue;
+			}
+			DBG1(DBG_IMC, "received PA-TNC error '%N' concerning message "
+				 "0x%08x/0x%08x", pa_tnc_error_code_names, error_code,
+				 untoh32(msg_info.ptr), untoh32(msg_info.ptr + 4));
+
+			switch (error_code)
+			{
+				case PA_ERROR_INVALID_PARAMETER:
+					offset = error_attr->get_offset(error_attr);
+					DBG1(DBG_IMC, "  occurred at offset of %u bytes", offset);
+					break;
+				case PA_ERROR_ATTR_TYPE_NOT_SUPPORTED:
+					attr_info = error_attr->get_attr_info(error_attr);
+					DBG1(DBG_IMC, "  unsupported attribute %#B", &attr_info);
+					break;
+				default:
+					break;
+			}
+
+			/* remove the processed IETF standard error attribute */
+			this->attributes->remove_at(this->attributes, enumerator);
+			fatal_error = TRUE;
+		}
+	}
+	enumerator->destroy(enumerator);
+
+	return fatal_error;
+}
+
+METHOD(pa_tnc_msg_t, create_attribute_enumerator, enumerator_t*,
+	private_pa_tnc_msg_t *this)
+{
+	return this->attributes->create_enumerator(this->attributes);
+}
+
+METHOD(pa_tnc_msg_t, create_error_enumerator, enumerator_t*,
+	private_pa_tnc_msg_t *this)
+{
+	return this->errors->create_enumerator(this->errors);
+}
+
+METHOD(pa_tnc_msg_t, destroy, void,
+	private_pa_tnc_msg_t *this)
+{
+	this->attributes->destroy_offset(this->attributes,
+									 offsetof(pa_tnc_attr_t, destroy)); 
+	this->errors->destroy_offset(this->errors,
+									 offsetof(pa_tnc_attr_t, destroy));
+	free(this->encoding.ptr);
+	free(this);
+}
+
+/**
+ * See header
+ */
+pa_tnc_msg_t *pa_tnc_msg_create_from_data(chunk_t data)
+{
+	private_pa_tnc_msg_t *this;
+
+	INIT(this,
+		.public = {
+			.get_encoding = _get_encoding,
+			.add_attribute = _add_attribute,
+			.build = _build,
+			.process = _process,
+			.process_ietf_std_errors = _process_ietf_std_errors,
+			.create_attribute_enumerator = _create_attribute_enumerator,
+			.create_error_enumerator = _create_error_enumerator,
+			.destroy = _destroy,
+		},
+		.encoding = chunk_clone(data),
+		.attributes = linked_list_create(),
+		.errors = linked_list_create(),
+	);
+
+	return &this->public;
+}
+
+/**
+ * See header
+ */
+pa_tnc_msg_t *pa_tnc_msg_create(void)
+{
+	return pa_tnc_msg_create_from_data(chunk_empty);
+}
+