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

2011-07-04 21:40:25 +02:00
parent 956759533f
commit d9cdab9249
15 changed files with 1474 additions and 4 deletions
@@ -0,0 +1,397 @@
+/*
+ * 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 "imv_scanner_state.h"
+
+#include <imv/imv_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/linked_list.h>
+#include <utils/lexparser.h>
+#include <debug.h>
+
+/* IMV definitions */
+
+static const char imv_name[] = "Scanner";
+
+#define IMV_VENDOR_ID	PEN_ITA
+#define IMV_SUBTYPE		PA_SUBTYPE_ITA_SCANNER
+
+static imv_agent_t *imv_scanner;
+
+typedef struct port_range_t port_range_t;
+
+struct port_range_t {
+	u_int16_t start, stop;
+};
+
+
+/**
+ * Default port policy 
+ *
+ * TRUE:  all server ports on the TNC client must be closed
+ * FALSE: any server port on the TNC client is allowed to be open
+ */
+static bool closed_port_policy = TRUE;
+
+/**
+ * List of TCP and UDP port ranges
+ *
+ * TRUE:  server ports on the TNC client that are allowed to be open
+ * FALSE: server ports on the TNC client that must be closed
+ */
+static linked_list_t *tcp_ports, *udp_ports;
+
+/**
+ * Get a TCP or UDP port list from strongswan.conf
+ */
+static linked_list_t* get_port_list(char *label)
+{
+	char key[40], *value;
+	linked_list_t *list;
+	chunk_t port_list, port_item, port_stop;
+	port_range_t *port_range;
+
+	list = linked_list_create();
+
+	snprintf(key, sizeof(key), "libimcv.plugins.imv-scanner.%s_ports", label);
+	value = lib->settings->get_str(lib->settings, key, NULL);
+	if (!value)
+	{
+		DBG1(DBG_IMV, "% not defined", key);
+		return list;
+	}
+	port_list = chunk_create(value, strlen(value));
+	DBG2(DBG_IMV, "list of %s ports that %s:", label,
+		 closed_port_policy ? "are allowed to be open" : "must be closed");
+
+	while (eat_whitespace(&port_list))
+	{
+		if (!extract_token(&port_item, ' ', &port_list))
+		{
+			/* reached last port item */
+			port_item = port_list;
+			port_list = chunk_empty;
+		}
+		port_range = malloc_thing(port_range_t);
+		port_range->start = atoi(port_item.ptr);;
+
+		if (extract_token(&port_stop, '-', &port_item))
+		{
+			port_range->stop = atoi(port_stop.ptr);
+		}
+		else
+		{
+			port_range->stop = port_range->start;
+		}
+		DBG2(DBG_IMV, "%5u - %5u", port_range->start, port_range->stop);
+		list->insert_last(list, port_range);
+	}
+
+	return list;
+}
+
+
+/*
+ * see section 3.7.1 of TCG TNC IF-IMV Specification 1.2
+ */
+TNC_Result TNC_IMV_Initialize(TNC_IMVID imv_id,
+							  TNC_Version min_version,
+							  TNC_Version max_version,
+							  TNC_Version *actual_version)
+{
+	if (imv_scanner)
+	{
+		DBG1(DBG_IMV, "IMV \"%s\" has already been initialized", imv_name);
+		return TNC_RESULT_ALREADY_INITIALIZED;
+	}
+	imv_scanner = imv_agent_create(imv_name, IMV_VENDOR_ID, IMV_SUBTYPE,
+								imv_id, actual_version);
+	if (!imv_scanner)
+	{
+		return TNC_RESULT_FATAL;
+	}
+	if (min_version > TNC_IFIMV_VERSION_1 || max_version < TNC_IFIMV_VERSION_1)
+	{
+		DBG1(DBG_IMV, "no common IF-IMV version");
+		return TNC_RESULT_NO_COMMON_VERSION;
+	}
+
+	/* set the default port policy to closed (TRUE) or open (FALSE) */
+	closed_port_policy = lib->settings->get_bool(lib->settings,
+						"libimcv.plugins.imv-scanner.closed_port_policy", TRUE);
+	DBG2(DBG_IMV, "default port policy is %s ports",
+						closed_port_policy ? "closed" : "open");
+
+	/* get the list of open|closed ports */
+	tcp_ports = get_port_list("tcp");
+	udp_ports = get_port_list("udp");
+
+	return TNC_RESULT_SUCCESS;
+}
+
+/**
+ * see section 3.7.2 of TCG TNC IF-IMV Specification 1.2
+ */
+TNC_Result TNC_IMV_NotifyConnectionChange(TNC_IMVID imv_id,
+										  TNC_ConnectionID connection_id,
+										  TNC_ConnectionState new_state)
+{
+	imv_state_t *state;
+
+	if (!imv_scanner)
+	{
+		DBG1(DBG_IMV, "IMV \"%s\" has not been initialized", imv_name);
+		return TNC_RESULT_NOT_INITIALIZED;
+	}
+	switch (new_state)
+	{
+		case TNC_CONNECTION_STATE_CREATE:
+			state = imv_scanner_state_create(connection_id);
+			return imv_scanner->create_state(imv_scanner, state);
+		case TNC_CONNECTION_STATE_DELETE:
+			return imv_scanner->delete_state(imv_scanner, connection_id);
+		default:
+			return imv_scanner->change_state(imv_scanner, connection_id,
+											 new_state, NULL);
+	}
+}
+
+/**
+ * see section 3.7.3 of TCG TNC IF-IMV Specification 1.2
+ */
+TNC_Result TNC_IMV_ReceiveMessage(TNC_IMVID imv_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;
+	imv_state_t *state;
+	enumerator_t *enumerator;
+	TNC_Result result;
+	bool fatal_error = FALSE;
+
+	if (!imv_scanner)
+	{
+		DBG1(DBG_IMV, "IMV \"%s\" has not been initialized", imv_name);
+		return TNC_RESULT_NOT_INITIALIZED;
+	}
+
+	/* get current IMV state */
+	if (!imv_scanner->get_state(imv_scanner, connection_id, &state))
+	{
+		return TNC_RESULT_FATAL;
+	}
+
+	/* parse received PA-TNC message and automatically handle any errors */ 
+	result = imv_scanner->receive_message(imv_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))
+	{
+		if (attr->get_vendor_id(attr) != PEN_IETF)
+		{
+			continue;
+		}
+
+		if (attr->get_type(attr) == IETF_ATTR_PA_TNC_ERROR)
+		{
+			ietf_attr_pa_tnc_error_t *error_attr;
+			pa_tnc_error_code_t error_code;
+			chunk_t msg_info, attr_info;
+
+			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_IMV, "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_IMV, "  unsupported attribute %#B", &attr_info);
+					break;
+				default:
+					break;
+			}
+			fatal_error = TRUE;
+		}
+		else if (attr->get_type(attr) == IETF_ATTR_PORT_FILTER)
+		{
+			ietf_attr_port_filter_t *attr_port_filter;
+			enumerator_t *enumerator;
+			u_int8_t protocol;
+			u_int16_t port;
+			char buf[BUF_LEN], *pos = buf;
+			size_t len = BUF_LEN;
+			bool blocked, compliant = TRUE;
+	
+			attr_port_filter = (ietf_attr_port_filter_t*)attr;
+			enumerator = attr_port_filter->create_port_enumerator(attr_port_filter);
+			while (enumerator->enumerate(enumerator, &blocked, &protocol, &port))
+			{
+				enumerator_t *e;
+				port_range_t *port_range;
+				bool passed, found = FALSE;
+				int written = 0;
+
+				if (blocked)
+				{
+					/* ignore closed ports */
+					continue;
+				}
+
+				e = (protocol == IPPROTO_TCP) ?
+							tcp_ports->create_enumerator(tcp_ports) :
+							udp_ports->create_enumerator(udp_ports);
+				while (e->enumerate(e, &port_range))
+				{
+					if (port >= port_range->start && port <= port_range->stop)
+					{
+						found = TRUE;
+						break;
+					}
+				}
+				e->destroy(e);
+
+				passed = (closed_port_policy == found);
+				DBG2(DBG_IMV, "%s port %5u %s: %s", 
+					(protocol == IPPROTO_TCP) ? "tcp" : "udp", port,
+					 blocked ? "closed" : "open", passed ? "ok" : "fatal");
+				if (!passed)
+				{
+					compliant = FALSE;
+					written = snprintf(pos, len, " %s/%u",
+									  (protocol == IPPROTO_TCP) ? "tcp" : "udp",
+									   port);
+					if (written < 0 || written >= len)
+					{
+						break;
+					}
+					pos += written;
+					len -= written;
+				}
+			} 
+			enumerator->destroy(enumerator);
+
+			if (compliant)
+			{
+				state->set_recommendation(state,
+								TNC_IMV_ACTION_RECOMMENDATION_ALLOW,
+								TNC_IMV_EVALUATION_RESULT_COMPLIANT);	
+			}
+			else
+			{
+				imv_scanner_state_t *imv_scanner_state;
+
+				imv_scanner_state = (imv_scanner_state_t*)state;
+				imv_scanner_state->set_violating_ports(imv_scanner_state, buf);
+				state->set_recommendation(state,
+								TNC_IMV_ACTION_RECOMMENDATION_NO_ACCESS,
+								TNC_IMV_EVALUATION_RESULT_NONCOMPLIANT_MAJOR);	
+			}		  
+		}		
+	}
+	enumerator->destroy(enumerator);
+	pa_tnc_msg->destroy(pa_tnc_msg);
+
+	if (fatal_error)
+	{
+		state->set_recommendation(state,
+								TNC_IMV_ACTION_RECOMMENDATION_NO_RECOMMENDATION,
+								TNC_IMV_EVALUATION_RESULT_ERROR);			  
+		return imv_scanner->provide_recommendation(imv_scanner, connection_id);
+	}
+
+	return imv_scanner->provide_recommendation(imv_scanner, connection_id);
+}
+
+/**
+ * see section 3.7.4 of TCG TNC IF-IMV Specification 1.2
+ */
+TNC_Result TNC_IMV_SolicitRecommendation(TNC_IMVID imv_id,
+										 TNC_ConnectionID connection_id)
+{
+	if (!imv_scanner)
+	{
+		DBG1(DBG_IMV, "IMV \"%s\" has not been initialized", imv_name);
+		return TNC_RESULT_NOT_INITIALIZED;
+	}
+	return imv_scanner->provide_recommendation(imv_scanner, connection_id);
+}
+
+/**
+ * see section 3.7.5 of TCG TNC IF-IMV Specification 1.2
+ */
+TNC_Result TNC_IMV_BatchEnding(TNC_IMVID imv_id,
+							   TNC_ConnectionID connection_id)
+{
+	if (!imv_scanner)
+	{
+		DBG1(DBG_IMV, "IMV \"%s\" has not been initialized", imv_name);
+		return TNC_RESULT_NOT_INITIALIZED;
+	}
+	return TNC_RESULT_SUCCESS;
+}
+
+/**
+ * see section 3.7.6 of TCG TNC IF-IMV Specification 1.2
+ */
+TNC_Result TNC_IMV_Terminate(TNC_IMVID imv_id)
+{
+	if (!imv_scanner)
+	{
+		DBG1(DBG_IMV, "IMV \"%s\" has not been initialized", imv_name);
+		return TNC_RESULT_NOT_INITIALIZED;
+	}
+	tcp_ports->destroy_function(tcp_ports, free);
+	udp_ports->destroy_function(udp_ports, free);
+	imv_scanner->destroy(imv_scanner);
+	imv_scanner = NULL;
+
+	return TNC_RESULT_SUCCESS;
+}
+
+/**
+ * see section 4.2.8.1 of TCG TNC IF-IMV Specification 1.2
+ */
+TNC_Result TNC_IMV_ProvideBindFunction(TNC_IMVID imv_id,
+									   TNC_TNCS_BindFunctionPointer bind_function)
+{
+	if (!imv_scanner)
+	{
+		DBG1(DBG_IMV, "IMV \"%s\" has not been initialized", imv_name);
+		return TNC_RESULT_NOT_INITIALIZED;
+	}
+	return imv_scanner->bind_functions(imv_scanner, bind_function);
+}