MQTTProperties.c 15 KB

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  1. /*******************************************************************************
  2. * Copyright (c) 2017, 2020 IBM Corp. and others
  3. *
  4. * All rights reserved. This program and the accompanying materials
  5. * are made available under the terms of the Eclipse Public License v2.0
  6. * and Eclipse Distribution License v1.0 which accompany this distribution.
  7. *
  8. * The Eclipse Public License is available at
  9. * https://www.eclipse.org/legal/epl-2.0/
  10. * and the Eclipse Distribution License is available at
  11. * http://www.eclipse.org/org/documents/edl-v10.php.
  12. *
  13. * Contributors:
  14. * Ian Craggs - initial API and implementation and/or initial documentation
  15. *******************************************************************************/
  16. #include "MQTTProperties.h"
  17. #include "MQTTPacket.h"
  18. #include "MQTTProtocolClient.h"
  19. #include "Heap.h"
  20. #include "StackTrace.h"
  21. #include <memory.h>
  22. #define ARRAY_SIZE(a) (sizeof(a) / sizeof(a[0]))
  23. static struct nameToType
  24. {
  25. enum MQTTPropertyCodes name;
  26. enum MQTTPropertyTypes type;
  27. } namesToTypes[] =
  28. {
  29. {MQTTPROPERTY_CODE_PAYLOAD_FORMAT_INDICATOR, MQTTPROPERTY_TYPE_BYTE},
  30. {MQTTPROPERTY_CODE_MESSAGE_EXPIRY_INTERVAL, MQTTPROPERTY_TYPE_FOUR_BYTE_INTEGER},
  31. {MQTTPROPERTY_CODE_CONTENT_TYPE, MQTTPROPERTY_TYPE_UTF_8_ENCODED_STRING},
  32. {MQTTPROPERTY_CODE_RESPONSE_TOPIC, MQTTPROPERTY_TYPE_UTF_8_ENCODED_STRING},
  33. {MQTTPROPERTY_CODE_CORRELATION_DATA, MQTTPROPERTY_TYPE_BINARY_DATA},
  34. {MQTTPROPERTY_CODE_SUBSCRIPTION_IDENTIFIER, MQTTPROPERTY_TYPE_VARIABLE_BYTE_INTEGER},
  35. {MQTTPROPERTY_CODE_SESSION_EXPIRY_INTERVAL, MQTTPROPERTY_TYPE_FOUR_BYTE_INTEGER},
  36. {MQTTPROPERTY_CODE_ASSIGNED_CLIENT_IDENTIFER, MQTTPROPERTY_TYPE_UTF_8_ENCODED_STRING},
  37. {MQTTPROPERTY_CODE_SERVER_KEEP_ALIVE, MQTTPROPERTY_TYPE_TWO_BYTE_INTEGER},
  38. {MQTTPROPERTY_CODE_AUTHENTICATION_METHOD, MQTTPROPERTY_TYPE_UTF_8_ENCODED_STRING},
  39. {MQTTPROPERTY_CODE_AUTHENTICATION_DATA, MQTTPROPERTY_TYPE_BINARY_DATA},
  40. {MQTTPROPERTY_CODE_REQUEST_PROBLEM_INFORMATION, MQTTPROPERTY_TYPE_BYTE},
  41. {MQTTPROPERTY_CODE_WILL_DELAY_INTERVAL, MQTTPROPERTY_TYPE_FOUR_BYTE_INTEGER},
  42. {MQTTPROPERTY_CODE_REQUEST_RESPONSE_INFORMATION, MQTTPROPERTY_TYPE_BYTE},
  43. {MQTTPROPERTY_CODE_RESPONSE_INFORMATION, MQTTPROPERTY_TYPE_UTF_8_ENCODED_STRING},
  44. {MQTTPROPERTY_CODE_SERVER_REFERENCE, MQTTPROPERTY_TYPE_UTF_8_ENCODED_STRING},
  45. {MQTTPROPERTY_CODE_REASON_STRING, MQTTPROPERTY_TYPE_UTF_8_ENCODED_STRING},
  46. {MQTTPROPERTY_CODE_RECEIVE_MAXIMUM, MQTTPROPERTY_TYPE_TWO_BYTE_INTEGER},
  47. {MQTTPROPERTY_CODE_TOPIC_ALIAS_MAXIMUM, MQTTPROPERTY_TYPE_TWO_BYTE_INTEGER},
  48. {MQTTPROPERTY_CODE_TOPIC_ALIAS, MQTTPROPERTY_TYPE_TWO_BYTE_INTEGER},
  49. {MQTTPROPERTY_CODE_MAXIMUM_QOS, MQTTPROPERTY_TYPE_BYTE},
  50. {MQTTPROPERTY_CODE_RETAIN_AVAILABLE, MQTTPROPERTY_TYPE_BYTE},
  51. {MQTTPROPERTY_CODE_USER_PROPERTY, MQTTPROPERTY_TYPE_UTF_8_STRING_PAIR},
  52. {MQTTPROPERTY_CODE_MAXIMUM_PACKET_SIZE, MQTTPROPERTY_TYPE_FOUR_BYTE_INTEGER},
  53. {MQTTPROPERTY_CODE_WILDCARD_SUBSCRIPTION_AVAILABLE, MQTTPROPERTY_TYPE_BYTE},
  54. {MQTTPROPERTY_CODE_SUBSCRIPTION_IDENTIFIERS_AVAILABLE, MQTTPROPERTY_TYPE_BYTE},
  55. {MQTTPROPERTY_CODE_SHARED_SUBSCRIPTION_AVAILABLE, MQTTPROPERTY_TYPE_BYTE}
  56. };
  57. static char* datadup(const MQTTLenString* str)
  58. {
  59. char* temp = malloc(str->len);
  60. if (temp)
  61. memcpy(temp, str->data, str->len);
  62. return temp;
  63. }
  64. int MQTTProperty_getType(enum MQTTPropertyCodes value)
  65. {
  66. int i, rc = -1;
  67. for (i = 0; i < ARRAY_SIZE(namesToTypes); ++i)
  68. {
  69. if (namesToTypes[i].name == value)
  70. {
  71. rc = namesToTypes[i].type;
  72. break;
  73. }
  74. }
  75. return rc;
  76. }
  77. int MQTTProperties_len(MQTTProperties* props)
  78. {
  79. /* properties length is an mbi */
  80. return (props == NULL) ? 1 : props->length + MQTTPacket_VBIlen(props->length);
  81. }
  82. /**
  83. * Add a new property to a property list
  84. * @param props the property list
  85. * @param prop the new property
  86. * @return code 0 is success
  87. */
  88. int MQTTProperties_add(MQTTProperties* props, const MQTTProperty* prop)
  89. {
  90. int rc = 0, type;
  91. if ((type = MQTTProperty_getType(prop->identifier)) < 0)
  92. {
  93. /*StackTrace_printStack(stdout);*/
  94. rc = MQTT_INVALID_PROPERTY_ID;
  95. goto exit;
  96. }
  97. else if (props->array == NULL)
  98. {
  99. props->max_count = 10;
  100. props->array = malloc(sizeof(MQTTProperty) * props->max_count);
  101. }
  102. else if (props->count == props->max_count)
  103. {
  104. props->max_count += 10;
  105. props->array = realloc(props->array, sizeof(MQTTProperty) * props->max_count);
  106. }
  107. if (props->array)
  108. {
  109. int len = 0;
  110. props->array[props->count++] = *prop;
  111. /* calculate length */
  112. switch (type)
  113. {
  114. case MQTTPROPERTY_TYPE_BYTE:
  115. len = 1;
  116. break;
  117. case MQTTPROPERTY_TYPE_TWO_BYTE_INTEGER:
  118. len = 2;
  119. break;
  120. case MQTTPROPERTY_TYPE_FOUR_BYTE_INTEGER:
  121. len = 4;
  122. break;
  123. case MQTTPROPERTY_TYPE_VARIABLE_BYTE_INTEGER:
  124. len = MQTTPacket_VBIlen(prop->value.integer4);
  125. break;
  126. case MQTTPROPERTY_TYPE_BINARY_DATA:
  127. case MQTTPROPERTY_TYPE_UTF_8_ENCODED_STRING:
  128. case MQTTPROPERTY_TYPE_UTF_8_STRING_PAIR:
  129. len = 2 + prop->value.data.len;
  130. props->array[props->count-1].value.data.data = datadup(&prop->value.data);
  131. if (type == MQTTPROPERTY_TYPE_UTF_8_STRING_PAIR)
  132. {
  133. len += 2 + prop->value.value.len;
  134. props->array[props->count-1].value.value.data = datadup(&prop->value.value);
  135. }
  136. break;
  137. }
  138. props->length += len + 1; /* add identifier byte */
  139. }
  140. else
  141. rc = PAHO_MEMORY_ERROR;
  142. exit:
  143. return rc;
  144. }
  145. int MQTTProperty_write(char** pptr, MQTTProperty* prop)
  146. {
  147. int rc = -1,
  148. type = -1;
  149. type = MQTTProperty_getType(prop->identifier);
  150. if (type >= MQTTPROPERTY_TYPE_BYTE && type <= MQTTPROPERTY_TYPE_UTF_8_STRING_PAIR)
  151. {
  152. writeChar(pptr, prop->identifier);
  153. switch (type)
  154. {
  155. case MQTTPROPERTY_TYPE_BYTE:
  156. writeChar(pptr, prop->value.byte);
  157. rc = 1;
  158. break;
  159. case MQTTPROPERTY_TYPE_TWO_BYTE_INTEGER:
  160. writeInt(pptr, prop->value.integer2);
  161. rc = 2;
  162. break;
  163. case MQTTPROPERTY_TYPE_FOUR_BYTE_INTEGER:
  164. writeInt4(pptr, prop->value.integer4);
  165. rc = 4;
  166. break;
  167. case MQTTPROPERTY_TYPE_VARIABLE_BYTE_INTEGER:
  168. rc = MQTTPacket_encode(*pptr, prop->value.integer4);
  169. *pptr += rc;
  170. break;
  171. case MQTTPROPERTY_TYPE_BINARY_DATA:
  172. case MQTTPROPERTY_TYPE_UTF_8_ENCODED_STRING:
  173. writeMQTTLenString(pptr, prop->value.data);
  174. rc = prop->value.data.len + 2; /* include length field */
  175. break;
  176. case MQTTPROPERTY_TYPE_UTF_8_STRING_PAIR:
  177. writeMQTTLenString(pptr, prop->value.data);
  178. writeMQTTLenString(pptr, prop->value.value);
  179. rc = prop->value.data.len + prop->value.value.len + 4; /* include length fields */
  180. break;
  181. }
  182. }
  183. return rc + 1; /* include identifier byte */
  184. }
  185. int MQTTProperties_write(char** pptr, const MQTTProperties* properties)
  186. {
  187. int rc = -1;
  188. int i = 0, len = 0;
  189. /* write the entire property list length first */
  190. if (properties == NULL)
  191. {
  192. *pptr += MQTTPacket_encode(*pptr, 0);
  193. rc = 1;
  194. }
  195. else
  196. {
  197. *pptr += MQTTPacket_encode(*pptr, properties->length);
  198. len = rc = 1;
  199. for (i = 0; i < properties->count; ++i)
  200. {
  201. rc = MQTTProperty_write(pptr, &properties->array[i]);
  202. if (rc < 0)
  203. break;
  204. else
  205. len += rc;
  206. }
  207. if (rc >= 0)
  208. rc = len;
  209. }
  210. return rc;
  211. }
  212. int MQTTProperty_read(MQTTProperty* prop, char** pptr, char* enddata)
  213. {
  214. int type = -1,
  215. len = -1;
  216. prop->identifier = readChar(pptr);
  217. type = MQTTProperty_getType(prop->identifier);
  218. if (type >= MQTTPROPERTY_TYPE_BYTE && type <= MQTTPROPERTY_TYPE_UTF_8_STRING_PAIR)
  219. {
  220. switch (type)
  221. {
  222. case MQTTPROPERTY_TYPE_BYTE:
  223. prop->value.byte = readChar(pptr);
  224. len = 1;
  225. break;
  226. case MQTTPROPERTY_TYPE_TWO_BYTE_INTEGER:
  227. prop->value.integer2 = readInt(pptr);
  228. len = 2;
  229. break;
  230. case MQTTPROPERTY_TYPE_FOUR_BYTE_INTEGER:
  231. prop->value.integer4 = readInt4(pptr);
  232. len = 4;
  233. break;
  234. case MQTTPROPERTY_TYPE_VARIABLE_BYTE_INTEGER:
  235. len = MQTTPacket_decodeBuf(*pptr, &prop->value.integer4);
  236. *pptr += len;
  237. break;
  238. case MQTTPROPERTY_TYPE_BINARY_DATA:
  239. case MQTTPROPERTY_TYPE_UTF_8_ENCODED_STRING:
  240. case MQTTPROPERTY_TYPE_UTF_8_STRING_PAIR:
  241. if ((len = MQTTLenStringRead(&prop->value.data, pptr, enddata)) == -1)
  242. break; /* error */
  243. if ((prop->value.data.data = datadup(&prop->value.data)) == NULL)
  244. {
  245. len = -1;
  246. break; /* error */
  247. }
  248. if (type == MQTTPROPERTY_TYPE_UTF_8_STRING_PAIR)
  249. {
  250. int proplen = MQTTLenStringRead(&prop->value.value, pptr, enddata);
  251. if (proplen == -1)
  252. {
  253. len = -1;
  254. free(prop->value.data.data);
  255. break;
  256. }
  257. len += proplen;
  258. if ((prop->value.value.data = datadup(&prop->value.value)) == NULL)
  259. {
  260. len = -1;
  261. free(prop->value.data.data);
  262. break;
  263. }
  264. }
  265. break;
  266. }
  267. }
  268. return (len == -1) ? -1 : len + 1; /* 1 byte for identifier */
  269. }
  270. int MQTTProperties_read(MQTTProperties* properties, char** pptr, char* enddata)
  271. {
  272. int rc = 0;
  273. unsigned int remlength = 0;
  274. FUNC_ENTRY;
  275. /* we assume an initialized properties structure */
  276. if (enddata - (*pptr) > 0) /* enough length to read the VBI? */
  277. {
  278. int proplen = 0;
  279. *pptr += MQTTPacket_decodeBuf(*pptr, &remlength);
  280. properties->length = remlength;
  281. while (remlength > 0)
  282. {
  283. if (properties->count == properties->max_count)
  284. {
  285. properties->max_count += 10;
  286. if (properties->max_count == 10)
  287. properties->array = malloc(sizeof(MQTTProperty) * properties->max_count);
  288. else
  289. properties->array = realloc(properties->array, sizeof(MQTTProperty) * properties->max_count);
  290. }
  291. if (properties->array == NULL)
  292. {
  293. rc = PAHO_MEMORY_ERROR;
  294. goto exit;
  295. }
  296. if ((proplen = MQTTProperty_read(&properties->array[properties->count], pptr, enddata)) > 0)
  297. remlength -= proplen;
  298. else
  299. break;
  300. properties->count++;
  301. }
  302. if (remlength == 0)
  303. rc = 1; /* data read successfully */
  304. }
  305. if (rc != 1 && properties->array != NULL)
  306. MQTTProperties_free(properties);
  307. exit:
  308. FUNC_EXIT_RC(rc);
  309. return rc;
  310. }
  311. struct {
  312. enum MQTTPropertyCodes value;
  313. const char* name;
  314. } nameToString[] =
  315. {
  316. {MQTTPROPERTY_CODE_PAYLOAD_FORMAT_INDICATOR, "PAYLOAD_FORMAT_INDICATOR"},
  317. {MQTTPROPERTY_CODE_MESSAGE_EXPIRY_INTERVAL, "MESSAGE_EXPIRY_INTERVAL"},
  318. {MQTTPROPERTY_CODE_CONTENT_TYPE, "CONTENT_TYPE"},
  319. {MQTTPROPERTY_CODE_RESPONSE_TOPIC, "RESPONSE_TOPIC"},
  320. {MQTTPROPERTY_CODE_CORRELATION_DATA, "CORRELATION_DATA"},
  321. {MQTTPROPERTY_CODE_SUBSCRIPTION_IDENTIFIER, "SUBSCRIPTION_IDENTIFIER"},
  322. {MQTTPROPERTY_CODE_SESSION_EXPIRY_INTERVAL, "SESSION_EXPIRY_INTERVAL"},
  323. {MQTTPROPERTY_CODE_ASSIGNED_CLIENT_IDENTIFER, "ASSIGNED_CLIENT_IDENTIFER"},
  324. {MQTTPROPERTY_CODE_SERVER_KEEP_ALIVE, "SERVER_KEEP_ALIVE"},
  325. {MQTTPROPERTY_CODE_AUTHENTICATION_METHOD, "AUTHENTICATION_METHOD"},
  326. {MQTTPROPERTY_CODE_AUTHENTICATION_DATA, "AUTHENTICATION_DATA"},
  327. {MQTTPROPERTY_CODE_REQUEST_PROBLEM_INFORMATION, "REQUEST_PROBLEM_INFORMATION"},
  328. {MQTTPROPERTY_CODE_WILL_DELAY_INTERVAL, "WILL_DELAY_INTERVAL"},
  329. {MQTTPROPERTY_CODE_REQUEST_RESPONSE_INFORMATION, "REQUEST_RESPONSE_INFORMATION"},
  330. {MQTTPROPERTY_CODE_RESPONSE_INFORMATION, "RESPONSE_INFORMATION"},
  331. {MQTTPROPERTY_CODE_SERVER_REFERENCE, "SERVER_REFERENCE"},
  332. {MQTTPROPERTY_CODE_REASON_STRING, "REASON_STRING"},
  333. {MQTTPROPERTY_CODE_RECEIVE_MAXIMUM, "RECEIVE_MAXIMUM"},
  334. {MQTTPROPERTY_CODE_TOPIC_ALIAS_MAXIMUM, "TOPIC_ALIAS_MAXIMUM"},
  335. {MQTTPROPERTY_CODE_TOPIC_ALIAS, "TOPIC_ALIAS"},
  336. {MQTTPROPERTY_CODE_MAXIMUM_QOS, "MAXIMUM_QOS"},
  337. {MQTTPROPERTY_CODE_RETAIN_AVAILABLE, "RETAIN_AVAILABLE"},
  338. {MQTTPROPERTY_CODE_USER_PROPERTY, "USER_PROPERTY"},
  339. {MQTTPROPERTY_CODE_MAXIMUM_PACKET_SIZE, "MAXIMUM_PACKET_SIZE"},
  340. {MQTTPROPERTY_CODE_WILDCARD_SUBSCRIPTION_AVAILABLE, "WILDCARD_SUBSCRIPTION_AVAILABLE"},
  341. {MQTTPROPERTY_CODE_SUBSCRIPTION_IDENTIFIERS_AVAILABLE, "SUBSCRIPTION_IDENTIFIERS_AVAILABLE"},
  342. {MQTTPROPERTY_CODE_SHARED_SUBSCRIPTION_AVAILABLE, "SHARED_SUBSCRIPTION_AVAILABLE"}
  343. };
  344. const char* MQTTPropertyName(enum MQTTPropertyCodes value)
  345. {
  346. int i = 0;
  347. const char* result = NULL;
  348. for (i = 0; i < ARRAY_SIZE(nameToString); ++i)
  349. {
  350. if (nameToString[i].value == value)
  351. {
  352. result = nameToString[i].name;
  353. break;
  354. }
  355. }
  356. return result;
  357. }
  358. void MQTTProperties_free(MQTTProperties* props)
  359. {
  360. int i = 0;
  361. FUNC_ENTRY;
  362. if (props == NULL)
  363. goto exit;
  364. for (i = 0; i < props->count; ++i)
  365. {
  366. int id = props->array[i].identifier;
  367. int type = MQTTProperty_getType(id);
  368. switch (type)
  369. {
  370. case MQTTPROPERTY_TYPE_BINARY_DATA:
  371. case MQTTPROPERTY_TYPE_UTF_8_ENCODED_STRING:
  372. case MQTTPROPERTY_TYPE_UTF_8_STRING_PAIR:
  373. free(props->array[i].value.data.data);
  374. if (type == MQTTPROPERTY_TYPE_UTF_8_STRING_PAIR)
  375. free(props->array[i].value.value.data);
  376. break;
  377. }
  378. }
  379. if (props->array)
  380. free(props->array);
  381. memset(props, '\0', sizeof(MQTTProperties)); /* zero all fields */
  382. exit:
  383. FUNC_EXIT;
  384. }
  385. MQTTProperties MQTTProperties_copy(const MQTTProperties* props)
  386. {
  387. int i = 0;
  388. MQTTProperties result = MQTTProperties_initializer;
  389. FUNC_ENTRY;
  390. for (i = 0; i < props->count; ++i)
  391. {
  392. int rc = 0;
  393. if ((rc = MQTTProperties_add(&result, &props->array[i])) != 0)
  394. Log(LOG_ERROR, -1, "Error from MQTTProperties add %d", rc);
  395. }
  396. FUNC_EXIT;
  397. return result;
  398. }
  399. int MQTTProperties_hasProperty(MQTTProperties *props, enum MQTTPropertyCodes propid)
  400. {
  401. int i = 0;
  402. int found = 0;
  403. for (i = 0; i < props->count; ++i)
  404. {
  405. if (propid == props->array[i].identifier)
  406. {
  407. found = 1;
  408. break;
  409. }
  410. }
  411. return found;
  412. }
  413. int MQTTProperties_propertyCount(MQTTProperties *props, enum MQTTPropertyCodes propid)
  414. {
  415. int i = 0;
  416. int count = 0;
  417. for (i = 0; i < props->count; ++i)
  418. {
  419. if (propid == props->array[i].identifier)
  420. count++;
  421. }
  422. return count;
  423. }
  424. int MQTTProperties_getNumericValueAt(MQTTProperties *props, enum MQTTPropertyCodes propid, int index)
  425. {
  426. int i = 0;
  427. int rc = -9999999;
  428. int cur_index = 0;
  429. for (i = 0; i < props->count; ++i)
  430. {
  431. int id = props->array[i].identifier;
  432. if (id == propid)
  433. {
  434. if (cur_index < index)
  435. {
  436. cur_index++;
  437. continue;
  438. }
  439. switch (MQTTProperty_getType(id))
  440. {
  441. case MQTTPROPERTY_TYPE_BYTE:
  442. rc = props->array[i].value.byte;
  443. break;
  444. case MQTTPROPERTY_TYPE_TWO_BYTE_INTEGER:
  445. rc = props->array[i].value.integer2;
  446. break;
  447. case MQTTPROPERTY_TYPE_FOUR_BYTE_INTEGER:
  448. case MQTTPROPERTY_TYPE_VARIABLE_BYTE_INTEGER:
  449. rc = props->array[i].value.integer4;
  450. break;
  451. default:
  452. rc = -999999;
  453. break;
  454. }
  455. break;
  456. }
  457. }
  458. return rc;
  459. }
  460. int MQTTProperties_getNumericValue(MQTTProperties *props, enum MQTTPropertyCodes propid)
  461. {
  462. return MQTTProperties_getNumericValueAt(props, propid, 0);
  463. }
  464. MQTTProperty* MQTTProperties_getPropertyAt(MQTTProperties *props, enum MQTTPropertyCodes propid, int index)
  465. {
  466. int i = 0;
  467. MQTTProperty* result = NULL;
  468. int cur_index = 0;
  469. for (i = 0; i < props->count; ++i)
  470. {
  471. int id = props->array[i].identifier;
  472. if (id == propid)
  473. {
  474. if (cur_index == index)
  475. {
  476. result = &props->array[i];
  477. break;
  478. }
  479. else
  480. cur_index++;
  481. }
  482. }
  483. return result;
  484. }
  485. MQTTProperty* MQTTProperties_getProperty(MQTTProperties *props, enum MQTTPropertyCodes propid)
  486. {
  487. return MQTTProperties_getPropertyAt(props, propid, 0);
  488. }