diff options
Diffstat (limited to 'src/libimcv/plugins/imc_scanner/imc_scanner.c')
| -rw-r--r-- | src/libimcv/plugins/imc_scanner/imc_scanner.c | 361 |
1 files changed, 361 insertions, 0 deletions
diff --git a/src/libimcv/plugins/imc_scanner/imc_scanner.c b/src/libimcv/plugins/imc_scanner/imc_scanner.c new file mode 100644 index 000000000..97133e575 --- /dev/null +++ b/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); +} |