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1.1 misho 1: /* 2: * Copyright (C) 2011-2015 Andreas Steffen 3: * HSR Hochschule fuer Technik Rapperswil 4: * 5: * This program is free software; you can redistribute it and/or modify it 6: * under the terms of the GNU General Public License as published by the 7: * Free Software Foundation; either version 2 of the License, or (at your 8: * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>. 9: * 10: * This program is distributed in the hope that it will be useful, but 11: * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 12: * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13: * for more details. 14: */ 15: 16: #include "imc_scanner_state.h" 17: 18: #include <imc/imc_agent.h> 19: #include <imc/imc_msg.h> 20: #include <ietf/ietf_attr.h> 21: #include <ietf/ietf_attr_attr_request.h> 22: #include <ietf/ietf_attr_port_filter.h> 23: 24: #include <tncif_pa_subtypes.h> 25: 26: #include <pen/pen.h> 27: #include <utils/lexparser.h> 28: #include <utils/debug.h> 29: 30: #include <stdio.h> 31: 32: /* IMC definitions */ 33: 34: static const char imc_name[] = "Scanner"; 35: 36: static pen_type_t msg_types[] = { 37: { PEN_IETF, PA_SUBTYPE_IETF_FIREWALL } 38: }; 39: 40: static imc_agent_t *imc_scanner; 41: 42: /** 43: * see section 3.8.1 of TCG TNC IF-IMC Specification 1.3 44: */ 45: TNC_Result TNC_IMC_Initialize(TNC_IMCID imc_id, 46: TNC_Version min_version, 47: TNC_Version max_version, 48: TNC_Version *actual_version) 49: { 50: if (imc_scanner) 51: { 52: DBG1(DBG_IMC, "IMC \"%s\" has already been initialized", imc_name); 53: return TNC_RESULT_ALREADY_INITIALIZED; 54: } 55: imc_scanner = imc_agent_create(imc_name, msg_types, countof(msg_types), 56: imc_id, actual_version); 57: if (!imc_scanner) 58: { 59: return TNC_RESULT_FATAL; 60: } 61: if (min_version > TNC_IFIMC_VERSION_1 || max_version < TNC_IFIMC_VERSION_1) 62: { 63: DBG1(DBG_IMC, "no common IF-IMC version"); 64: return TNC_RESULT_NO_COMMON_VERSION; 65: } 66: return TNC_RESULT_SUCCESS; 67: } 68: 69: /** 70: * see section 3.8.2 of TCG TNC IF-IMC Specification 1.3 71: */ 72: TNC_Result TNC_IMC_NotifyConnectionChange(TNC_IMCID imc_id, 73: TNC_ConnectionID connection_id, 74: TNC_ConnectionState new_state) 75: { 76: imc_state_t *state; 77: 78: if (!imc_scanner) 79: { 80: DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name); 81: return TNC_RESULT_NOT_INITIALIZED; 82: } 83: switch (new_state) 84: { 85: case TNC_CONNECTION_STATE_CREATE: 86: state = imc_scanner_state_create(connection_id); 87: return imc_scanner->create_state(imc_scanner, state); 88: case TNC_CONNECTION_STATE_DELETE: 89: return imc_scanner->delete_state(imc_scanner, connection_id); 90: default: 91: return imc_scanner->change_state(imc_scanner, connection_id, 92: new_state, NULL); 93: } 94: } 95: 96: /** 97: * Determine all TCP and UDP server sockets listening on physical interfaces 98: */ 99: static bool do_netstat(ietf_attr_port_filter_t *attr) 100: { 101: FILE *file; 102: char buf[BUF_LEN]; 103: chunk_t line, token; 104: int n = 0; 105: bool success = FALSE; 106: const char system_v4[] = "127.0.1.1"; 107: const char loopback_v4[] = "127.0.0.1"; 108: const char loopback_v6[] = "::1"; 109: 110: /* Open a pipe stream for reading the output of the netstat command */ 111: file = popen("/bin/netstat -n -l -p -4 -6 --inet", "r"); 112: if (!file) 113: { 114: DBG1(DBG_IMC, "failed to run netstat command"); 115: return FALSE; 116: } 117: 118: /* Read the output a line at a time */ 119: while (fgets(buf, sizeof(buf), file)) 120: { 121: u_char *pos; 122: uint8_t new_protocol, protocol; 123: uint16_t new_port, port; 124: int i; 125: enumerator_t *enumerator; 126: bool allowed, found = FALSE; 127: 128: DBG2(DBG_IMC, "%.*s", (int)(strlen(buf)-1), buf); 129: 130: if (n++ < 2) 131: { 132: /* skip the first two header lines */ 133: continue; 134: } 135: line = chunk_create(buf, strlen(buf)); 136: 137: /* Extract the IP protocol type */ 138: if (!extract_token(&token, ' ', &line)) 139: { 140: DBG1(DBG_IMC, "protocol field in netstat output not found"); 141: goto end; 142: } 143: if (match("tcp", &token) || match("tcp6", &token)) 144: { 145: new_protocol = IPPROTO_TCP; 146: } 147: else if (match("udp", &token) || match("udp6", &token)) 148: { 149: new_protocol = IPPROTO_UDP; 150: } 151: else 152: { 153: DBG1(DBG_IMC, "skipped unknown IP protocol in netstat output"); 154: continue; 155: } 156: 157: /* Skip the Recv-Q and Send-Q fields */ 158: for (i = 0; i < 3; i++) 159: { 160: if (!eat_whitespace(&line) || !extract_token(&token, ' ', &line)) 161: { 162: token = chunk_empty; 163: break; 164: } 165: } 166: if (token.len == 0) 167: { 168: DBG1(DBG_IMC, "local address field in netstat output not found"); 169: goto end; 170: } 171: 172: /* Find the local port appended to the local address */ 173: pos = token.ptr + token.len; 174: while (*--pos != ':' && --token.len); 175: if (*pos != ':') 176: { 177: DBG1(DBG_IMC, "local port field in netstat output not found"); 178: goto end; 179: } 180: token.len--; 181: 182: /* ignore ports of IPv4 and IPv6 loopback interfaces 183: and the internal system IPv4 address */ 184: if ((token.len == strlen(system_v4) && 185: memeq(system_v4, token.ptr, token.len)) || 186: (token.len == strlen(loopback_v4) && 187: memeq(loopback_v4, token.ptr, token.len)) || 188: (token.len == strlen(loopback_v6) && 189: memeq(loopback_v6, token.ptr, token.len))) 190: { 191: continue; 192: } 193: 194: /* convert the port string to an integer */ 195: new_port = atoi(pos+1); 196: 197: /* check if the there is already a port entry */ 198: enumerator = attr->create_port_enumerator(attr); 199: while (enumerator->enumerate(enumerator, &allowed, &protocol, &port)) 200: { 201: if (new_port == port && new_protocol == protocol) 202: { 203: found = TRUE; 204: } 205: } 206: enumerator->destroy(enumerator); 207: 208: /* Skip the duplicate port entry */ 209: if (found) 210: { 211: continue; 212: } 213: 214: /* Add new port entry */ 215: attr->add_port(attr, FALSE, new_protocol, new_port); 216: } 217: 218: /* Successfully completed the parsing of the netstat output */ 219: success = TRUE; 220: 221: end: 222: /* Close the pipe stream */ 223: pclose(file); 224: return success; 225: } 226: 227: /** 228: * Add IETF Port Filter attribute to the send queue 229: */ 230: static TNC_Result add_port_filter(imc_msg_t *msg) 231: { 232: pa_tnc_attr_t *attr; 233: ietf_attr_port_filter_t *attr_port_filter; 234: 235: attr = ietf_attr_port_filter_create(pen_type_create(PEN_IETF, 236: IETF_ATTR_PORT_FILTER)); 237: attr->set_noskip_flag(attr, TRUE); 238: attr_port_filter = (ietf_attr_port_filter_t*)attr; 239: if (!do_netstat(attr_port_filter)) 240: { 241: attr->destroy(attr); 242: return TNC_RESULT_FATAL; 243: } 244: msg->add_attribute(msg, attr); 245: 246: return TNC_RESULT_SUCCESS; 247: } 248: 249: /** 250: * see section 3.8.3 of TCG TNC IF-IMC Specification 1.3 251: */ 252: TNC_Result TNC_IMC_BeginHandshake(TNC_IMCID imc_id, 253: TNC_ConnectionID connection_id) 254: { 255: imc_state_t *state; 256: imc_msg_t *out_msg; 257: TNC_Result result = TNC_RESULT_SUCCESS; 258: 259: if (!imc_scanner) 260: { 261: DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name); 262: return TNC_RESULT_NOT_INITIALIZED; 263: } 264: if (!imc_scanner->get_state(imc_scanner, connection_id, &state)) 265: { 266: return TNC_RESULT_FATAL; 267: } 268: if (lib->settings->get_bool(lib->settings, 269: "%s.plugins.imc-scanner.push_info", TRUE, lib->ns)) 270: { 271: out_msg = imc_msg_create(imc_scanner, state, connection_id, imc_id, 272: TNC_IMVID_ANY, msg_types[0]); 273: result = add_port_filter(out_msg); 274: if (result == TNC_RESULT_SUCCESS) 275: { 276: /* send PA-TNC message with the excl flag not set */ 277: result = out_msg->send(out_msg, FALSE); 278: } 279: out_msg->destroy(out_msg); 280: } 281: 282: return result; 283: } 284: 285: static TNC_Result receive_message(imc_msg_t *in_msg) 286: { 287: imc_msg_t *out_msg; 288: enumerator_t *enumerator; 289: pa_tnc_attr_t *attr; 290: pen_type_t attr_type; 291: TNC_Result result = TNC_RESULT_SUCCESS; 292: bool fatal_error = FALSE; 293: 294: /* generate an outgoing PA-TNC message - we might need it */ 295: out_msg = imc_msg_create_as_reply(in_msg); 296: 297: /* parse received PA-TNC message and handle local and remote errors */ 298: result = in_msg->receive(in_msg, out_msg, &fatal_error); 299: if (result != TNC_RESULT_SUCCESS) 300: { 301: out_msg->destroy(out_msg); 302: return result; 303: } 304: 305: /* analyze PA-TNC attributes */ 306: enumerator = in_msg->create_attribute_enumerator(in_msg); 307: while (enumerator->enumerate(enumerator, &attr)) 308: { 309: attr_type = attr->get_type(attr); 310: 311: if (attr_type.vendor_id != PEN_IETF) 312: { 313: continue; 314: } 315: if (attr_type.type == IETF_ATTR_ATTRIBUTE_REQUEST) 316: { 317: ietf_attr_attr_request_t *attr_cast; 318: pen_type_t *entry; 319: enumerator_t *e; 320: 321: attr_cast = (ietf_attr_attr_request_t*)attr; 322: 323: e = attr_cast->create_enumerator(attr_cast); 324: while (e->enumerate(e, &entry)) 325: { 326: if (entry->vendor_id != PEN_IETF) 327: { 328: continue; 329: } 330: switch (entry->type) 331: { 332: case IETF_ATTR_PORT_FILTER: 333: result = add_port_filter(out_msg); 334: break; 335: default: 336: break; 337: } 338: } 339: e->destroy(e); 340: } 341: } 342: enumerator->destroy(enumerator); 343: 344: if (fatal_error) 345: { 346: result = TNC_RESULT_FATAL; 347: } 348: else if (result == TNC_RESULT_SUCCESS) 349: { 350: /* send PA-TNC message with the EXCL flag set */ 351: result = out_msg->send(out_msg, TRUE); 352: } 353: out_msg->destroy(out_msg); 354: 355: return result; 356: } 357: 358: /** 359: * see section 3.8.4 of TCG TNC IF-IMC Specification 1.3 360: 361: */ 362: TNC_Result TNC_IMC_ReceiveMessage(TNC_IMCID imc_id, 363: TNC_ConnectionID connection_id, 364: TNC_BufferReference msg, 365: TNC_UInt32 msg_len, 366: TNC_MessageType msg_type) 367: { 368: imc_state_t *state; 369: imc_msg_t *in_msg; 370: TNC_Result result; 371: 372: if (!imc_scanner) 373: { 374: DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name); 375: return TNC_RESULT_NOT_INITIALIZED; 376: } 377: if (!imc_scanner->get_state(imc_scanner, connection_id, &state)) 378: { 379: return TNC_RESULT_FATAL; 380: } 381: 382: in_msg = imc_msg_create_from_data(imc_scanner, state, connection_id, 383: msg_type, chunk_create(msg, msg_len)); 384: result = receive_message(in_msg); 385: in_msg->destroy(in_msg); 386: 387: return result; 388: } 389: 390: /** 391: * see section 3.8.6 of TCG TNC IF-IMV Specification 1.3 392: */ 393: TNC_Result TNC_IMC_ReceiveMessageLong(TNC_IMCID imc_id, 394: TNC_ConnectionID connection_id, 395: TNC_UInt32 msg_flags, 396: TNC_BufferReference msg, 397: TNC_UInt32 msg_len, 398: TNC_VendorID msg_vid, 399: TNC_MessageSubtype msg_subtype, 400: TNC_UInt32 src_imv_id, 401: TNC_UInt32 dst_imc_id) 402: { 403: imc_state_t *state; 404: imc_msg_t *in_msg; 405: TNC_Result result; 406: 407: if (!imc_scanner) 408: { 409: DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name); 410: return TNC_RESULT_NOT_INITIALIZED; 411: } 412: if (!imc_scanner->get_state(imc_scanner, connection_id, &state)) 413: { 414: return TNC_RESULT_FATAL; 415: } 416: in_msg = imc_msg_create_from_long_data(imc_scanner, state, connection_id, 417: src_imv_id, dst_imc_id, msg_vid, msg_subtype, 418: chunk_create(msg, msg_len)); 419: result = receive_message(in_msg); 420: in_msg->destroy(in_msg); 421: 422: return result; 423: } 424: 425: /** 426: * see section 3.8.7 of TCG TNC IF-IMC Specification 1.3 427: */ 428: TNC_Result TNC_IMC_BatchEnding(TNC_IMCID imc_id, 429: TNC_ConnectionID connection_id) 430: { 431: if (!imc_scanner) 432: { 433: DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name); 434: return TNC_RESULT_NOT_INITIALIZED; 435: } 436: return TNC_RESULT_SUCCESS; 437: } 438: 439: /** 440: * see section 3.8.8 of TCG TNC IF-IMC Specification 1.3 441: */ 442: TNC_Result TNC_IMC_Terminate(TNC_IMCID imc_id) 443: { 444: if (!imc_scanner) 445: { 446: DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name); 447: return TNC_RESULT_NOT_INITIALIZED; 448: } 449: imc_scanner->destroy(imc_scanner); 450: imc_scanner = NULL; 451: 452: return TNC_RESULT_SUCCESS; 453: } 454: 455: /** 456: * see section 4.2.8.1 of TCG TNC IF-IMC Specification 1.3 457: */ 458: TNC_Result TNC_IMC_ProvideBindFunction(TNC_IMCID imc_id, 459: TNC_TNCC_BindFunctionPointer bind_function) 460: { 461: if (!imc_scanner) 462: { 463: DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name); 464: return TNC_RESULT_NOT_INITIALIZED; 465: } 466: return imc_scanner->bind_functions(imc_scanner, bind_function); 467: }