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/*
* Copyright (C) 2011-2012 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 <imc/imc_msg.h>
#include <ietf/ietf_attr.h>
#include <ietf/ietf_attr_attr_request.h>
#include <ietf/ietf_attr_port_filter.h>
#include <tncif_pa_subtypes.h>
#include <pen/pen.h>
#include <utils/lexparser.h>
#include <utils/debug.h>
#include <stdio.h>
/* IMC definitions */
static const char imc_name[] = "Scanner";
static pen_type_t msg_types[] = {
{ PEN_IETF, PA_SUBTYPE_IETF_VPN }
};
static imc_agent_t *imc_scanner;
/**
* see section 3.8.1 of TCG TNC IF-IMC Specification 1.3
*/
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, msg_types, countof(msg_types),
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 3.8.2 of TCG TNC IF-IMC Specification 1.3
*/
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_HANDSHAKE:
if (imc_scanner->change_state(imc_scanner, connection_id, new_state,
&state) != TNC_RESULT_SUCCESS)
{
return TNC_RESULT_FATAL;
}
state->set_result(state, imc_id,
TNC_IMV_EVALUATION_RESULT_DONT_KNOW);
return TNC_RESULT_SUCCESS;
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;
const char system_v4[] = "127.0.1.1";
const char loopback_v4[] = "127.0.0.1";
const char loopback_v6[] = "::1";
/* Open a pipe stream for reading the output of the netstat commmand */
file = popen("/bin/netstat -n -l -p -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, sizeof(buf), 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", (int)(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;
}
token.len--;
/* ignore ports of IPv4 and IPv6 loopback interfaces
and the internal system IPv4 address */
if ((token.len == strlen(system_v4) &&
memeq(system_v4, token.ptr, token.len)) ||
(token.len == strlen(loopback_v4) &&
memeq(loopback_v4, token.ptr, token.len)) ||
(token.len == strlen(loopback_v6) &&
memeq(loopback_v6, token.ptr, token.len)))
{
continue;
}
/* 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;
}
/**
* Add IETF Port Filter attribute to the send queue
*/
static TNC_Result add_port_filter(imc_msg_t *msg)
{
pa_tnc_attr_t *attr;
ietf_attr_port_filter_t *attr_port_filter;
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->add_attribute(msg, attr);
return TNC_RESULT_SUCCESS;
}
/**
* see section 3.8.3 of TCG TNC IF-IMC Specification 1.3
*/
TNC_Result TNC_IMC_BeginHandshake(TNC_IMCID imc_id,
TNC_ConnectionID connection_id)
{
imc_state_t *state;
imc_msg_t *out_msg;
TNC_Result result = TNC_RESULT_SUCCESS;
if (!imc_scanner)
{
DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
return TNC_RESULT_NOT_INITIALIZED;
}
if (!imc_scanner->get_state(imc_scanner, connection_id, &state))
{
return TNC_RESULT_FATAL;
}
if (lib->settings->get_bool(lib->settings,
"%s.plugins.imc-scanner.push_info", TRUE, lib->ns))
{
out_msg = imc_msg_create(imc_scanner, state, connection_id, imc_id,
TNC_IMVID_ANY, msg_types[0]);
result = add_port_filter(out_msg);
if (result == TNC_RESULT_SUCCESS)
{
/* send PA-TNC message with the excl flag not set */
result = out_msg->send(out_msg, FALSE);
}
out_msg->destroy(out_msg);
}
return result;
}
static TNC_Result receive_message(imc_msg_t *in_msg)
{
imc_msg_t *out_msg;
enumerator_t *enumerator;
pa_tnc_attr_t *attr;
pen_type_t attr_type;
TNC_Result result = TNC_RESULT_SUCCESS;
bool fatal_error = FALSE;
/* parse received PA-TNC message and handle local and remote errors */
result = in_msg->receive(in_msg, &fatal_error);
if (result != TNC_RESULT_SUCCESS)
{
return result;
}
out_msg = imc_msg_create_as_reply(in_msg);
/* analyze PA-TNC attributes */
enumerator = in_msg->create_attribute_enumerator(in_msg);
while (enumerator->enumerate(enumerator, &attr))
{
attr_type = attr->get_type(attr);
if (attr_type.vendor_id != PEN_IETF)
{
continue;
}
if (attr_type.type == IETF_ATTR_ATTRIBUTE_REQUEST)
{
ietf_attr_attr_request_t *attr_cast;
pen_type_t *entry;
enumerator_t *e;
attr_cast = (ietf_attr_attr_request_t*)attr;
e = attr_cast->create_enumerator(attr_cast);
while (e->enumerate(e, &entry))
{
if (entry->vendor_id != PEN_IETF)
{
continue;
}
switch (entry->type)
{
case IETF_ATTR_PORT_FILTER:
result = add_port_filter(out_msg);
break;
default:
break;
}
}
e->destroy(e);
}
}
enumerator->destroy(enumerator);
if (fatal_error)
{
result = TNC_RESULT_FATAL;
}
else if (result == TNC_RESULT_SUCCESS)
{
result = out_msg->send(out_msg, TRUE);
}
out_msg->destroy(out_msg);
return result;
}
/**
* see section 3.8.4 of TCG TNC IF-IMC Specification 1.3
*/
TNC_Result TNC_IMC_ReceiveMessage(TNC_IMCID imc_id,
TNC_ConnectionID connection_id,
TNC_BufferReference msg,
TNC_UInt32 msg_len,
TNC_MessageType msg_type)
{
imc_state_t *state;
imc_msg_t *in_msg;
TNC_Result result;
if (!imc_scanner)
{
DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
return TNC_RESULT_NOT_INITIALIZED;
}
if (!imc_scanner->get_state(imc_scanner, connection_id, &state))
{
return TNC_RESULT_FATAL;
}
in_msg = imc_msg_create_from_data(imc_scanner, state, connection_id,
msg_type, chunk_create(msg, msg_len));
result = receive_message(in_msg);
in_msg->destroy(in_msg);
return result;
}
/**
* see section 3.8.6 of TCG TNC IF-IMV Specification 1.3
*/
TNC_Result TNC_IMC_ReceiveMessageLong(TNC_IMCID imc_id,
TNC_ConnectionID connection_id,
TNC_UInt32 msg_flags,
TNC_BufferReference msg,
TNC_UInt32 msg_len,
TNC_VendorID msg_vid,
TNC_MessageSubtype msg_subtype,
TNC_UInt32 src_imv_id,
TNC_UInt32 dst_imc_id)
{
imc_state_t *state;
imc_msg_t *in_msg;
TNC_Result result;
if (!imc_scanner)
{
DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
return TNC_RESULT_NOT_INITIALIZED;
}
if (!imc_scanner->get_state(imc_scanner, connection_id, &state))
{
return TNC_RESULT_FATAL;
}
in_msg = imc_msg_create_from_long_data(imc_scanner, state, connection_id,
src_imv_id, dst_imc_id, msg_vid, msg_subtype,
chunk_create(msg, msg_len));
result = receive_message(in_msg);
in_msg->destroy(in_msg);
return result;
}
/**
* see section 3.8.7 of TCG TNC IF-IMC Specification 1.3
*/
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 3.8.8 of TCG TNC IF-IMC Specification 1.3
*/
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 1.3
*/
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);
}
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