added ITA Scanner IMC/IMV pair which detects open server ports on TNC clients

src/libimcv/plugins/imc_scanner/Makefile.am

@@ -0,0 +1,16 @@
+
+INCLUDES = -I$(top_srcdir)/src/libstrongswan -I$(top_srcdir)/src/libtncif \
+	-I$(top_srcdir)/src/libimcv
+
+AM_CFLAGS = -rdynamic
+
+plugin_LTLIBRARIES = libstrongswan-imc-scanner.la
+
+libstrongswan_imc_scanner_la_LIBADD = $(top_builddir)/src/libimcv/libimcv.la \
+	$(top_builddir)/src/libstrongswan/libstrongswan.la
+
+libstrongswan_imc_scanner_la_SOURCES = imc_scanner.c \
+	imc_scanner_state.h imc_scanner_state.c
+
+libstrongswan_imc_scanner_la_LDFLAGS = -module -avoid-version
+

src/libimcv/plugins/imc_scanner/imc_scanner.c

@@ -0,0 +1,361 @@
+/*
+ * 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 "imc_scanner_state.h"
+
+#include <imc/imc_agent.h>
+#include <pa_tnc/pa_tnc_msg.h>
+#include <ietf/ietf_attr.h>
+#include <ietf/ietf_attr_pa_tnc_error.h>
+#include <ietf/ietf_attr_port_filter.h>
+
+#include <tncif_names.h>
+#include <tncif_pa_subtypes.h>
+
+#include <pen/pen.h>
+#include <utils/lexparser.h>
+#include <debug.h>
+
+#include <stdio.h>
+
+/* IMC definitions */
+
+static const char imc_name[] = "Scanner";
+
+#define IMC_VENDOR_ID	PEN_ITA
+#define IMC_SUBTYPE		PA_SUBTYPE_ITA_SCANNER
+
+static imc_agent_t *imc_scanner;
+ 
+/**
+ * see section 3.7.1 of TCG TNC IF-IMC Specification 1.2
+ */
+TNC_Result TNC_IMC_Initialize(TNC_IMCID imc_id,
+							  TNC_Version min_version,
+							  TNC_Version max_version,
+							  TNC_Version *actual_version)
+{
+	if (imc_scanner)
+	{
+		DBG1(DBG_IMC, "IMC \"%s\" has already been initialized", imc_name);
+		return TNC_RESULT_ALREADY_INITIALIZED;
+	}
+	imc_scanner = imc_agent_create(imc_name, IMC_VENDOR_ID, IMC_SUBTYPE,
+								imc_id, actual_version);
+	if (!imc_scanner)
+	{
+		return TNC_RESULT_FATAL;
+	}
+	if (min_version > TNC_IFIMC_VERSION_1 || max_version < TNC_IFIMC_VERSION_1)
+	{
+		DBG1(DBG_IMC, "no common IF-IMC version");
+		return TNC_RESULT_NO_COMMON_VERSION;
+	}
+	return TNC_RESULT_SUCCESS;
+}
+
+/**
+ * see section 3.7.2 of TCG TNC IF-IMC Specification 1.2
+ */
+TNC_Result TNC_IMC_NotifyConnectionChange(TNC_IMCID imc_id,
+										  TNC_ConnectionID connection_id,
+										  TNC_ConnectionState new_state)
+{
+	imc_state_t *state;
+
+	if (!imc_scanner)
+	{
+		DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
+		return TNC_RESULT_NOT_INITIALIZED;
+	}
+	switch (new_state)
+	{
+		case TNC_CONNECTION_STATE_CREATE:
+			state = imc_scanner_state_create(connection_id);
+			return imc_scanner->create_state(imc_scanner, state);
+		case TNC_CONNECTION_STATE_DELETE:
+			return imc_scanner->delete_state(imc_scanner, connection_id);
+		default:
+			return imc_scanner->change_state(imc_scanner, connection_id,
+											 new_state, NULL);
+	}
+}
+
+/**
+ * Determine all TCP and UDP server sockets listening on physical interfaces
+ */
+static bool do_netstat(ietf_attr_port_filter_t *attr)
+{
+	FILE *file;
+	char buf[BUF_LEN];
+	chunk_t line, token;
+	int n = 0;
+	bool success = FALSE;
+
+	/* Open a pipe stream for reading the output of the netstat commmand */
+	file = popen("/bin/netstat -n -l -4 -6 --inet", "r");
+	if (!file)
+	{
+		DBG1(DBG_IMC, "Failed to run netstat command");
+		return FALSE;
+	}
+
+	/* Read the output a line at a time */
+	while (fgets(buf, BUF_LEN-1, file))
+	{
+		u_char *pos;
+		u_int8_t new_protocol, protocol;
+		u_int16_t new_port, port;
+		int i;
+		enumerator_t *enumerator;
+		bool allowed, found = FALSE;
+
+		DBG2(DBG_IMC, "%.*s", strlen(buf)-1, buf);
+
+		if (n++ < 2)
+		{
+			/* skip the first two header lines */
+			continue;
+		}
+		line = chunk_create(buf, strlen(buf));
+
+		/* Extract the IP protocol type */
+		if (!extract_token(&token, ' ', &line))
+		{
+			DBG1(DBG_IMC, "Protocol field in netstat output not found");
+			goto end;
+		}
+		if (match("tcp", &token) || match("tcp6", &token))
+		{
+			new_protocol = IPPROTO_TCP;
+		}
+		else if (match("udp", &token) || match("udp6", &token))
+		{
+			new_protocol = IPPROTO_UDP;
+		}
+		else
+		{
+			DBG1(DBG_IMC, "Skipped unknown IP protocol in netstat output");
+			continue;
+		}
+
+		/* Skip the Recv-Q and Send-Q fields */
+		for (i = 0; i < 3; i++)
+		{
+			if (!eat_whitespace(&line) || !extract_token(&token, ' ', &line))
+			{
+				token = chunk_empty;
+				break;
+			}
+		}
+		if (token.len == 0)
+		{
+			DBG1(DBG_IMC, "Local Address field in netstat output not found");
+			goto end;
+		}
+
+		/* Find the local port appended to the local address */
+		pos = token.ptr + token.len;
+		while (*--pos != ':' && --token.len);
+		if (*pos != ':')
+		{
+			DBG1(DBG_IMC, "Local port field in netstat output not found");
+			goto end;
+		}
+
+		/* convert the port string to an integer */
+		new_port = atoi(pos+1);
+
+		/* check if the there is already a port entry */
+		enumerator = attr->create_port_enumerator(attr);
+		while (enumerator->enumerate(enumerator, &allowed, &protocol, &port))
+		{
+			if (new_port == port && new_protocol == protocol)
+			{
+				found = TRUE;
+			}
+		}
+		enumerator->destroy(enumerator);
+		
+		/* Skip the duplicate port entry */
+		if (found)
+		{
+			continue;
+		}
+
+		/* Add new port entry */
+		attr->add_port(attr, FALSE, new_protocol, new_port);
+	}
+
+	/* Successfully completed the parsing of the netstat output */
+	success = TRUE;
+
+end:
+	/* Close the pipe stream */
+	pclose(file);
+	return success;
+}
+
+static TNC_Result send_message(TNC_ConnectionID connection_id)
+{
+	pa_tnc_msg_t *msg;
+	pa_tnc_attr_t *attr;
+	ietf_attr_port_filter_t *attr_port_filter;
+	TNC_Result result;
+
+	attr = ietf_attr_port_filter_create();
+	attr->set_noskip_flag(attr, TRUE);
+	attr_port_filter = (ietf_attr_port_filter_t*)attr;
+	if (!do_netstat(attr_port_filter))
+	{
+		attr->destroy(attr);
+		return TNC_RESULT_FATAL;
+	}
+	msg = pa_tnc_msg_create();
+	msg->add_attribute(msg, attr);
+	msg->build(msg);
+	result = imc_scanner->send_message(imc_scanner, connection_id,
+									   msg->get_encoding(msg));	
+	msg->destroy(msg);
+
+	return result;
+}
+
+/**
+ * see section 3.7.3 of TCG TNC IF-IMC Specification 1.2
+ */
+TNC_Result TNC_IMC_BeginHandshake(TNC_IMCID imc_id,
+								  TNC_ConnectionID connection_id)
+{
+	if (!imc_scanner)
+	{
+		DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
+		return TNC_RESULT_NOT_INITIALIZED;
+	}
+	return send_message(connection_id);
+}
+
+/**
+ * see section 3.7.4 of TCG TNC IF-IMC Specification 1.2
+ */
+TNC_Result TNC_IMC_ReceiveMessage(TNC_IMCID imc_id,
+								  TNC_ConnectionID connection_id,
+								  TNC_BufferReference msg,
+								  TNC_UInt32 msg_len,
+								  TNC_MessageType msg_type)
+{
+	pa_tnc_msg_t *pa_tnc_msg;
+	pa_tnc_attr_t *attr;
+	enumerator_t *enumerator;
+	TNC_Result result;
+	bool fatal_error = FALSE;
+
+	if (!imc_scanner)
+	{
+		DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
+		return TNC_RESULT_NOT_INITIALIZED;
+	}
+
+	/* parse received PA-TNC message and automatically handle any errors */ 
+	result = imc_scanner->receive_message(imc_scanner, connection_id,
+									   chunk_create(msg, msg_len), msg_type,
+									   &pa_tnc_msg);
+
+	/* no parsed PA-TNC attributes available if an error occurred */
+	if (!pa_tnc_msg)
+	{
+		return result;
+	}
+
+	/* analyze PA-TNC attributes */
+	enumerator = pa_tnc_msg->create_attribute_enumerator(pa_tnc_msg);
+	while (enumerator->enumerate(enumerator, &attr))
+	{
+		ietf_attr_pa_tnc_error_t *error_attr;
+		pa_tnc_error_code_t error_code;
+		chunk_t msg_info, attr_info;
+
+		if (attr->get_vendor_id(attr) != PEN_IETF &&
+			attr->get_type(attr) != IETF_ATTR_PA_TNC_ERROR)
+		{
+			continue;
+		}
+
+		error_attr = (ietf_attr_pa_tnc_error_t*)attr;
+		error_code = error_attr->get_error_code(error_attr);
+		msg_info = error_attr->get_msg_info(error_attr);
+		DBG1(DBG_IMC, "received PA-TNC error '%N' concerning message %#B",
+			 pa_tnc_error_code_names, error_code, &msg_info);
+
+		switch (error_code)
+		{
+			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;
+		}
+		fatal_error = TRUE;
+	}
+	enumerator->destroy(enumerator);
+	pa_tnc_msg->destroy(pa_tnc_msg);
+
+	/* if no error occurred then always return the same response */
+	return fatal_error ? TNC_RESULT_FATAL : send_message(connection_id);
+}
+
+/**
+ * see section 3.7.5 of TCG TNC IF-IMC Specification 1.2
+ */
+TNC_Result TNC_IMC_BatchEnding(TNC_IMCID imc_id,
+							   TNC_ConnectionID connection_id)
+{
+	if (!imc_scanner)
+	{
+		DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
+		return TNC_RESULT_NOT_INITIALIZED;
+	}
+	return TNC_RESULT_SUCCESS;
+}
+
+/**
+ * see section 3.7.6 of TCG TNC IF-IMC Specification 1.2
+ */
+TNC_Result TNC_IMC_Terminate(TNC_IMCID imc_id)
+{
+	if (!imc_scanner)
+	{
+		DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
+		return TNC_RESULT_NOT_INITIALIZED;
+	}
+	imc_scanner->destroy(imc_scanner);
+	imc_scanner = NULL;
+
+	return TNC_RESULT_SUCCESS;
+}
+
+/**
+ * see section 4.2.8.1 of TCG TNC IF-IMC Specification 1.2
+ */
+TNC_Result TNC_IMC_ProvideBindFunction(TNC_IMCID imc_id,
+									   TNC_TNCC_BindFunctionPointer bind_function)
+{
+	if (!imc_scanner)
+	{
+		DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
+		return TNC_RESULT_NOT_INITIALIZED;
+	}
+	return imc_scanner->bind_functions(imc_scanner, bind_function);
+}

src/libimcv/plugins/imc_scanner/imc_scanner_state.c

@@ -0,0 +1,82 @@
+/*
+ * 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 "imc_scanner_state.h"
+
+#include <debug.h>
+
+typedef struct private_imc_scanner_state_t private_imc_scanner_state_t;
+
+/**
+ * Private data of an imc_scanner_state_t object.
+ */
+struct private_imc_scanner_state_t {
+
+	/**
+	 * Public members of imc_scanner_state_t
+	 */
+	imc_scanner_state_t public;
+
+	/**
+	 * TNCCS connection ID
+	 */
+	TNC_ConnectionID connection_id;
+
+	/**
+	 * TNCCS connection state
+	 */
+	TNC_ConnectionState state;
+};
+
+METHOD(imc_state_t, get_connection_id, TNC_ConnectionID,
+	private_imc_scanner_state_t *this)
+{
+	return this->connection_id;
+}
+
+METHOD(imc_state_t, change_state, void,
+	private_imc_scanner_state_t *this, TNC_ConnectionState new_state)
+{
+	this->state = new_state;
+}
+
+METHOD(imc_state_t, destroy, void,
+	private_imc_scanner_state_t *this)
+{
+	free(this);
+}
+
+/**
+ * Described in header.
+ */
+imc_state_t *imc_scanner_state_create(TNC_ConnectionID connection_id)
+{
+	private_imc_scanner_state_t *this;
+
+	INIT(this,
+		.public = {
+			.interface = {
+				.get_connection_id = _get_connection_id,
+				.change_state = _change_state,
+				.destroy = _destroy,
+			},
+		},
+		.state = TNC_CONNECTION_STATE_CREATE,
+		.connection_id = connection_id,
+	);
+	
+	return &this->public.interface;
+}
+
+

src/libimcv/plugins/imc_scanner/imc_scanner_state.h

@@ -0,0 +1,47 @@
+/*
+ * 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.
+ */
+
+/**
+ *
+ * @defgroup imc_scanner_state_t imc_scanner_state
+ * @{ @ingroup imc_scanner_state
+ */
+
+#ifndef IMC_SCANNER_STATE_H_
+#define IMC_SCANNER_STATE_H_
+
+#include <imc/imc_state.h>
+#include <library.h>
+
+typedef struct imc_scanner_state_t imc_scanner_state_t;
+
+/**
+ * Internal state of an imc_scanner_t connection instance
+ */
+struct imc_scanner_state_t {
+
+	/**
+	 * imc_state_t interface
+	 */
+	imc_state_t interface;
+};
+
+/**
+ * Create an imc_scanner_state_t instance
+ *
+ * @param id		connection ID
+ */
+imc_state_t* imc_scanner_state_create(TNC_ConnectionID id);
+
+#endif /** IMC_SCANNER_STATE_H_ @}*/