InetAddress.cpp 17 KB

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  1. /*
  2. * Copyright (c)2019 ZeroTier, Inc.
  3. *
  4. * Use of this software is governed by the Business Source License included
  5. * in the LICENSE.TXT file in the project's root directory.
  6. *
  7. * Change Date: 2025-01-01
  8. *
  9. * On the date above, in accordance with the Business Source License, use
  10. * of this software will be governed by version 2.0 of the Apache License.
  11. */
  12. /****/
  13. #include <stdio.h>
  14. #include <string.h>
  15. #include <stdint.h>
  16. #include <string>
  17. #include "Constants.hpp"
  18. #include "InetAddress.hpp"
  19. #include "Utils.hpp"
  20. namespace ZeroTier {
  21. const InetAddress InetAddress::LO4((const void *)("\x7f\x00\x00\x01"),4,0);
  22. const InetAddress InetAddress::LO6((const void *)("\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01"),16,0);
  23. InetAddress::IpScope InetAddress::ipScope() const
  24. {
  25. switch(ss_family) {
  26. case AF_INET: {
  27. const uint32_t ip = Utils::ntoh((uint32_t)reinterpret_cast<const struct sockaddr_in *>(this)->sin_addr.s_addr);
  28. switch(ip >> 24) {
  29. case 0x00: return IP_SCOPE_NONE; // 0.0.0.0/8 (reserved, never used)
  30. case 0x06: return IP_SCOPE_PSEUDOPRIVATE; // 6.0.0.0/8 (US Army)
  31. case 0x0a: return IP_SCOPE_PRIVATE; // 10.0.0.0/8
  32. case 0x0b: return IP_SCOPE_PSEUDOPRIVATE; // 11.0.0.0/8 (US DoD)
  33. case 0x15: return IP_SCOPE_PSEUDOPRIVATE; // 21.0.0.0/8 (US DDN-RVN)
  34. case 0x16: return IP_SCOPE_PSEUDOPRIVATE; // 22.0.0.0/8 (US DISA)
  35. case 0x19: return IP_SCOPE_PSEUDOPRIVATE; // 25.0.0.0/8 (UK Ministry of Defense)
  36. case 0x1a: return IP_SCOPE_PSEUDOPRIVATE; // 26.0.0.0/8 (US DISA)
  37. case 0x1c: return IP_SCOPE_PSEUDOPRIVATE; // 28.0.0.0/8 (US DSI-North)
  38. case 0x1d: return IP_SCOPE_PSEUDOPRIVATE; // 29.0.0.0/8 (US DISA)
  39. case 0x1e: return IP_SCOPE_PSEUDOPRIVATE; // 30.0.0.0/8 (US DISA)
  40. case 0x33: return IP_SCOPE_PSEUDOPRIVATE; // 51.0.0.0/8 (UK Department of Social Security)
  41. case 0x37: return IP_SCOPE_PSEUDOPRIVATE; // 55.0.0.0/8 (US DoD)
  42. case 0x38: return IP_SCOPE_PSEUDOPRIVATE; // 56.0.0.0/8 (US Postal Service)
  43. case 0x64:
  44. if ((ip & 0xffc00000) == 0x64400000) return IP_SCOPE_PRIVATE; // 100.64.0.0/10
  45. break;
  46. case 0x7f: return IP_SCOPE_LOOPBACK; // 127.0.0.0/8
  47. case 0xa9:
  48. if ((ip & 0xffff0000) == 0xa9fe0000) return IP_SCOPE_LINK_LOCAL; // 169.254.0.0/16
  49. break;
  50. case 0xac:
  51. if ((ip & 0xfff00000) == 0xac100000) return IP_SCOPE_PRIVATE; // 172.16.0.0/12
  52. break;
  53. case 0xc0:
  54. if ((ip & 0xffff0000) == 0xc0a80000) return IP_SCOPE_PRIVATE; // 192.168.0.0/16
  55. break;
  56. case 0xc6:
  57. if ((ip & 0xfffe0000) == 0xc6120000) return IP_SCOPE_PRIVATE; // 198.18.0.0/15
  58. break;
  59. case 0xff: return IP_SCOPE_NONE; // 255.0.0.0/8 (broadcast, or unused/unusable)
  60. }
  61. switch(ip >> 28) {
  62. case 0xe: return IP_SCOPE_MULTICAST; // 224.0.0.0/4
  63. case 0xf: return IP_SCOPE_PSEUDOPRIVATE; // 240.0.0.0/4 ("reserved," usually unusable)
  64. }
  65. return IP_SCOPE_GLOBAL;
  66. } break;
  67. case AF_INET6: {
  68. const unsigned char *ip = reinterpret_cast<const unsigned char *>(reinterpret_cast<const struct sockaddr_in6 *>(this)->sin6_addr.s6_addr);
  69. if ((ip[0] & 0xf0) == 0xf0) {
  70. if (ip[0] == 0xff) return IP_SCOPE_MULTICAST; // ff00::/8
  71. if ((ip[0] == 0xfe)&&((ip[1] & 0xc0) == 0x80)) {
  72. unsigned int k = 2;
  73. while ((!ip[k])&&(k < 15)) ++k;
  74. if ((k == 15)&&(ip[15] == 0x01))
  75. return IP_SCOPE_LOOPBACK; // fe80::1/128
  76. else return IP_SCOPE_LINK_LOCAL; // fe80::/10
  77. }
  78. if ((ip[0] & 0xfe) == 0xfc) return IP_SCOPE_PRIVATE; // fc00::/7
  79. }
  80. unsigned int k = 0;
  81. while ((!ip[k])&&(k < 15)) ++k;
  82. if (k == 15) { // all 0's except last byte
  83. if (ip[15] == 0x01) return IP_SCOPE_LOOPBACK; // ::1/128
  84. if (ip[15] == 0x00) return IP_SCOPE_NONE; // ::/128
  85. }
  86. return IP_SCOPE_GLOBAL;
  87. } break;
  88. }
  89. return IP_SCOPE_NONE;
  90. }
  91. void InetAddress::set(const void *ipBytes,unsigned int ipLen,unsigned int port)
  92. {
  93. memset(this,0,sizeof(InetAddress));
  94. if (ipLen == 4) {
  95. uint32_t ipb[1];
  96. memcpy(ipb,ipBytes,4);
  97. ss_family = AF_INET;
  98. reinterpret_cast<struct sockaddr_in *>(this)->sin_addr.s_addr = ipb[0];
  99. reinterpret_cast<struct sockaddr_in *>(this)->sin_port = Utils::hton((uint16_t)port);
  100. } else if (ipLen == 16) {
  101. ss_family = AF_INET6;
  102. memcpy(reinterpret_cast<struct sockaddr_in6 *>(this)->sin6_addr.s6_addr,ipBytes,16);
  103. reinterpret_cast<struct sockaddr_in6 *>(this)->sin6_port = Utils::hton((uint16_t)port);
  104. }
  105. }
  106. char *InetAddress::toString(char buf[64]) const
  107. {
  108. char *p = toIpString(buf);
  109. if (*p) {
  110. while (*p) ++p;
  111. *(p++) = '/';
  112. Utils::decimal(port(),p);
  113. }
  114. return buf;
  115. }
  116. char *InetAddress::toIpString(char buf[64]) const
  117. {
  118. buf[0] = (char)0;
  119. switch(ss_family) {
  120. case AF_INET: {
  121. #ifdef _WIN32
  122. inet_ntop(AF_INET, (void*)&reinterpret_cast<const struct sockaddr_in *>(this)->sin_addr.s_addr, buf, INET_ADDRSTRLEN);
  123. #else
  124. inet_ntop(AF_INET, &reinterpret_cast<const struct sockaddr_in *>(this)->sin_addr.s_addr, buf, INET_ADDRSTRLEN);
  125. #endif
  126. } break;
  127. case AF_INET6: {
  128. #ifdef _WIN32
  129. inet_ntop(AF_INET6, (void*)reinterpret_cast<const struct sockaddr_in6 *>(this)->sin6_addr.s6_addr, buf, INET6_ADDRSTRLEN);
  130. #else
  131. inet_ntop(AF_INET6, reinterpret_cast<const struct sockaddr_in6 *>(this)->sin6_addr.s6_addr, buf, INET6_ADDRSTRLEN);
  132. #endif
  133. } break;
  134. }
  135. return buf;
  136. }
  137. bool InetAddress::fromString(const char *ipSlashPort)
  138. {
  139. char buf[64];
  140. memset(this,0,sizeof(InetAddress));
  141. if (!*ipSlashPort)
  142. return true;
  143. if (!Utils::scopy(buf,sizeof(buf),ipSlashPort))
  144. return false;
  145. char *portAt = buf;
  146. while ((*portAt)&&(*portAt != '/'))
  147. ++portAt;
  148. unsigned int port = 0;
  149. if (*portAt) {
  150. *(portAt++) = (char)0;
  151. port = Utils::strToUInt(portAt) & 0xffff;
  152. }
  153. if (strchr(buf,':')) {
  154. struct sockaddr_in6 *const in6 = reinterpret_cast<struct sockaddr_in6 *>(this);
  155. inet_pton(AF_INET6, buf, &in6->sin6_addr.s6_addr);
  156. in6->sin6_family = AF_INET6;
  157. in6->sin6_port = Utils::hton((uint16_t)port);
  158. return true;
  159. } else if (strchr(buf,'.')) {
  160. struct sockaddr_in *const in = reinterpret_cast<struct sockaddr_in *>(this);
  161. inet_pton(AF_INET, buf, &in->sin_addr.s_addr);
  162. in->sin_family = AF_INET;
  163. in->sin_port = Utils::hton((uint16_t)port);
  164. return true;
  165. } else {
  166. return false;
  167. }
  168. }
  169. InetAddress InetAddress::netmask() const
  170. {
  171. InetAddress r(*this);
  172. switch(r.ss_family) {
  173. case AF_INET:
  174. reinterpret_cast<struct sockaddr_in *>(&r)->sin_addr.s_addr = Utils::hton((uint32_t)(0xffffffff << (32 - netmaskBits())));
  175. break;
  176. case AF_INET6: {
  177. uint64_t nm[2];
  178. const unsigned int bits = netmaskBits();
  179. if(bits) {
  180. nm[0] = Utils::hton((uint64_t)((bits >= 64) ? 0xffffffffffffffffULL : (0xffffffffffffffffULL << (64 - bits))));
  181. nm[1] = Utils::hton((uint64_t)((bits <= 64) ? 0ULL : (0xffffffffffffffffULL << (128 - bits))));
  182. } else {
  183. nm[0] = 0;
  184. nm[1] = 0;
  185. }
  186. memcpy(reinterpret_cast<struct sockaddr_in6 *>(&r)->sin6_addr.s6_addr,nm,16);
  187. } break;
  188. }
  189. return r;
  190. }
  191. InetAddress InetAddress::broadcast() const
  192. {
  193. if (ss_family == AF_INET) {
  194. InetAddress r(*this);
  195. reinterpret_cast<struct sockaddr_in *>(&r)->sin_addr.s_addr |= Utils::hton((uint32_t)(0xffffffff >> netmaskBits()));
  196. return r;
  197. }
  198. return InetAddress();
  199. }
  200. InetAddress InetAddress::network() const
  201. {
  202. InetAddress r(*this);
  203. switch(r.ss_family) {
  204. case AF_INET:
  205. reinterpret_cast<struct sockaddr_in *>(&r)->sin_addr.s_addr &= Utils::hton((uint32_t)(0xffffffff << (32 - netmaskBits())));
  206. break;
  207. case AF_INET6: {
  208. uint64_t nm[2];
  209. const unsigned int bits = netmaskBits();
  210. memcpy(nm,reinterpret_cast<struct sockaddr_in6 *>(&r)->sin6_addr.s6_addr,16);
  211. nm[0] &= Utils::hton((uint64_t)((bits >= 64) ? 0xffffffffffffffffULL : (0xffffffffffffffffULL << (64 - bits))));
  212. nm[1] &= Utils::hton((uint64_t)((bits <= 64) ? 0ULL : (0xffffffffffffffffULL << (128 - bits))));
  213. memcpy(reinterpret_cast<struct sockaddr_in6 *>(&r)->sin6_addr.s6_addr,nm,16);
  214. } break;
  215. }
  216. return r;
  217. }
  218. bool InetAddress::isEqualPrefix(const InetAddress &addr) const
  219. {
  220. if (addr.ss_family == ss_family) {
  221. switch(ss_family) {
  222. case AF_INET6: {
  223. const InetAddress mask(netmask());
  224. InetAddress addr_mask(addr.netmask());
  225. const uint8_t *n = reinterpret_cast<const uint8_t *>(reinterpret_cast<const struct sockaddr_in6 *>(&addr_mask)->sin6_addr.s6_addr);
  226. const uint8_t *m = reinterpret_cast<const uint8_t *>(reinterpret_cast<const struct sockaddr_in6 *>(&mask)->sin6_addr.s6_addr);
  227. const uint8_t *a = reinterpret_cast<const uint8_t *>(reinterpret_cast<const struct sockaddr_in6 *>(&addr)->sin6_addr.s6_addr);
  228. const uint8_t *b = reinterpret_cast<const uint8_t *>(reinterpret_cast<const struct sockaddr_in6 *>(this)->sin6_addr.s6_addr);
  229. for(unsigned int i=0;i<16;++i) {
  230. if ((a[i] & m[i]) != (b[i] & n[i]))
  231. return false;
  232. }
  233. return true;
  234. }
  235. }
  236. }
  237. return false;
  238. }
  239. bool InetAddress::containsAddress(const InetAddress &addr) const
  240. {
  241. if (addr.ss_family == ss_family) {
  242. switch(ss_family) {
  243. case AF_INET: {
  244. const unsigned int bits = netmaskBits();
  245. if (bits == 0)
  246. return true;
  247. return ( (Utils::ntoh((uint32_t)reinterpret_cast<const struct sockaddr_in *>(&addr)->sin_addr.s_addr) >> (32 - bits)) == (Utils::ntoh((uint32_t)reinterpret_cast<const struct sockaddr_in *>(this)->sin_addr.s_addr) >> (32 - bits)) );
  248. }
  249. case AF_INET6: {
  250. const InetAddress mask(netmask());
  251. const uint8_t *m = reinterpret_cast<const uint8_t *>(reinterpret_cast<const struct sockaddr_in6 *>(&mask)->sin6_addr.s6_addr);
  252. const uint8_t *a = reinterpret_cast<const uint8_t *>(reinterpret_cast<const struct sockaddr_in6 *>(&addr)->sin6_addr.s6_addr);
  253. const uint8_t *b = reinterpret_cast<const uint8_t *>(reinterpret_cast<const struct sockaddr_in6 *>(this)->sin6_addr.s6_addr);
  254. for(unsigned int i=0;i<16;++i) {
  255. if ((a[i] & m[i]) != b[i])
  256. return false;
  257. }
  258. return true;
  259. }
  260. }
  261. }
  262. return false;
  263. }
  264. bool InetAddress::isNetwork() const
  265. {
  266. switch(ss_family) {
  267. case AF_INET: {
  268. unsigned int bits = netmaskBits();
  269. if (bits <= 0)
  270. return false;
  271. if (bits >= 32)
  272. return false;
  273. uint32_t ip = Utils::ntoh((uint32_t)reinterpret_cast<const struct sockaddr_in *>(this)->sin_addr.s_addr);
  274. return ((ip & (0xffffffff >> bits)) == 0);
  275. }
  276. case AF_INET6: {
  277. unsigned int bits = netmaskBits();
  278. if (bits <= 0)
  279. return false;
  280. if (bits >= 128)
  281. return false;
  282. const unsigned char *ip = reinterpret_cast<const unsigned char *>(reinterpret_cast<const struct sockaddr_in6 *>(this)->sin6_addr.s6_addr);
  283. unsigned int p = bits / 8;
  284. if ((ip[p++] & (0xff >> (bits % 8))) != 0)
  285. return false;
  286. while (p < 16) {
  287. if (ip[p++])
  288. return false;
  289. }
  290. return true;
  291. }
  292. }
  293. return false;
  294. }
  295. bool InetAddress::operator==(const InetAddress &a) const
  296. {
  297. if (ss_family == a.ss_family) {
  298. switch(ss_family) {
  299. case AF_INET:
  300. return (
  301. (reinterpret_cast<const struct sockaddr_in *>(this)->sin_port == reinterpret_cast<const struct sockaddr_in *>(&a)->sin_port)&&
  302. (reinterpret_cast<const struct sockaddr_in *>(this)->sin_addr.s_addr == reinterpret_cast<const struct sockaddr_in *>(&a)->sin_addr.s_addr));
  303. break;
  304. case AF_INET6:
  305. return (
  306. (reinterpret_cast<const struct sockaddr_in6 *>(this)->sin6_port == reinterpret_cast<const struct sockaddr_in6 *>(&a)->sin6_port)&&
  307. (reinterpret_cast<const struct sockaddr_in6 *>(this)->sin6_flowinfo == reinterpret_cast<const struct sockaddr_in6 *>(&a)->sin6_flowinfo)&&
  308. (memcmp(reinterpret_cast<const struct sockaddr_in6 *>(this)->sin6_addr.s6_addr,reinterpret_cast<const struct sockaddr_in6 *>(&a)->sin6_addr.s6_addr,16) == 0)&&
  309. (reinterpret_cast<const struct sockaddr_in6 *>(this)->sin6_scope_id == reinterpret_cast<const struct sockaddr_in6 *>(&a)->sin6_scope_id));
  310. break;
  311. default:
  312. return (memcmp(this,&a,sizeof(InetAddress)) == 0);
  313. }
  314. }
  315. return false;
  316. }
  317. bool InetAddress::operator<(const InetAddress &a) const
  318. {
  319. if (ss_family < a.ss_family)
  320. return true;
  321. else if (ss_family == a.ss_family) {
  322. switch(ss_family) {
  323. case AF_INET:
  324. if (reinterpret_cast<const struct sockaddr_in *>(this)->sin_port < reinterpret_cast<const struct sockaddr_in *>(&a)->sin_port)
  325. return true;
  326. else if (reinterpret_cast<const struct sockaddr_in *>(this)->sin_port == reinterpret_cast<const struct sockaddr_in *>(&a)->sin_port) {
  327. if (reinterpret_cast<const struct sockaddr_in *>(this)->sin_addr.s_addr < reinterpret_cast<const struct sockaddr_in *>(&a)->sin_addr.s_addr)
  328. return true;
  329. }
  330. break;
  331. case AF_INET6:
  332. if (reinterpret_cast<const struct sockaddr_in6 *>(this)->sin6_port < reinterpret_cast<const struct sockaddr_in6 *>(&a)->sin6_port)
  333. return true;
  334. else if (reinterpret_cast<const struct sockaddr_in6 *>(this)->sin6_port == reinterpret_cast<const struct sockaddr_in6 *>(&a)->sin6_port) {
  335. if (reinterpret_cast<const struct sockaddr_in6 *>(this)->sin6_flowinfo < reinterpret_cast<const struct sockaddr_in6 *>(&a)->sin6_flowinfo)
  336. return true;
  337. else if (reinterpret_cast<const struct sockaddr_in6 *>(this)->sin6_flowinfo == reinterpret_cast<const struct sockaddr_in6 *>(&a)->sin6_flowinfo) {
  338. if (memcmp(reinterpret_cast<const struct sockaddr_in6 *>(this)->sin6_addr.s6_addr,reinterpret_cast<const struct sockaddr_in6 *>(&a)->sin6_addr.s6_addr,16) < 0)
  339. return true;
  340. else if (memcmp(reinterpret_cast<const struct sockaddr_in6 *>(this)->sin6_addr.s6_addr,reinterpret_cast<const struct sockaddr_in6 *>(&a)->sin6_addr.s6_addr,16) == 0) {
  341. if (reinterpret_cast<const struct sockaddr_in6 *>(this)->sin6_scope_id < reinterpret_cast<const struct sockaddr_in6 *>(&a)->sin6_scope_id)
  342. return true;
  343. }
  344. }
  345. }
  346. break;
  347. default:
  348. return (memcmp(this,&a,sizeof(InetAddress)) < 0);
  349. }
  350. }
  351. return false;
  352. }
  353. InetAddress InetAddress::makeIpv6LinkLocal(const MAC &mac)
  354. {
  355. struct sockaddr_in6 sin6;
  356. sin6.sin6_family = AF_INET6;
  357. sin6.sin6_addr.s6_addr[0] = 0xfe;
  358. sin6.sin6_addr.s6_addr[1] = 0x80;
  359. sin6.sin6_addr.s6_addr[2] = 0x00;
  360. sin6.sin6_addr.s6_addr[3] = 0x00;
  361. sin6.sin6_addr.s6_addr[4] = 0x00;
  362. sin6.sin6_addr.s6_addr[5] = 0x00;
  363. sin6.sin6_addr.s6_addr[6] = 0x00;
  364. sin6.sin6_addr.s6_addr[7] = 0x00;
  365. sin6.sin6_addr.s6_addr[8] = mac[0] & 0xfd;
  366. sin6.sin6_addr.s6_addr[9] = mac[1];
  367. sin6.sin6_addr.s6_addr[10] = mac[2];
  368. sin6.sin6_addr.s6_addr[11] = 0xff;
  369. sin6.sin6_addr.s6_addr[12] = 0xfe;
  370. sin6.sin6_addr.s6_addr[13] = mac[3];
  371. sin6.sin6_addr.s6_addr[14] = mac[4];
  372. sin6.sin6_addr.s6_addr[15] = mac[5];
  373. sin6.sin6_port = Utils::hton((uint16_t)64);
  374. return InetAddress(sin6);
  375. }
  376. InetAddress InetAddress::makeIpv6rfc4193(uint64_t nwid,uint64_t zeroTierAddress)
  377. {
  378. InetAddress r;
  379. struct sockaddr_in6 *const sin6 = reinterpret_cast<struct sockaddr_in6 *>(&r);
  380. sin6->sin6_family = AF_INET6;
  381. sin6->sin6_addr.s6_addr[0] = 0xfd;
  382. sin6->sin6_addr.s6_addr[1] = (uint8_t)(nwid >> 56);
  383. sin6->sin6_addr.s6_addr[2] = (uint8_t)(nwid >> 48);
  384. sin6->sin6_addr.s6_addr[3] = (uint8_t)(nwid >> 40);
  385. sin6->sin6_addr.s6_addr[4] = (uint8_t)(nwid >> 32);
  386. sin6->sin6_addr.s6_addr[5] = (uint8_t)(nwid >> 24);
  387. sin6->sin6_addr.s6_addr[6] = (uint8_t)(nwid >> 16);
  388. sin6->sin6_addr.s6_addr[7] = (uint8_t)(nwid >> 8);
  389. sin6->sin6_addr.s6_addr[8] = (uint8_t)nwid;
  390. sin6->sin6_addr.s6_addr[9] = 0x99;
  391. sin6->sin6_addr.s6_addr[10] = 0x93;
  392. sin6->sin6_addr.s6_addr[11] = (uint8_t)(zeroTierAddress >> 32);
  393. sin6->sin6_addr.s6_addr[12] = (uint8_t)(zeroTierAddress >> 24);
  394. sin6->sin6_addr.s6_addr[13] = (uint8_t)(zeroTierAddress >> 16);
  395. sin6->sin6_addr.s6_addr[14] = (uint8_t)(zeroTierAddress >> 8);
  396. sin6->sin6_addr.s6_addr[15] = (uint8_t)zeroTierAddress;
  397. sin6->sin6_port = Utils::hton((uint16_t)88); // /88 includes 0xfd + network ID, discriminating by device ID below that
  398. return r;
  399. }
  400. InetAddress InetAddress::makeIpv66plane(uint64_t nwid,uint64_t zeroTierAddress)
  401. {
  402. nwid ^= (nwid >> 32);
  403. InetAddress r;
  404. struct sockaddr_in6 *const sin6 = reinterpret_cast<struct sockaddr_in6 *>(&r);
  405. sin6->sin6_family = AF_INET6;
  406. sin6->sin6_addr.s6_addr[0] = 0xfc;
  407. sin6->sin6_addr.s6_addr[1] = (uint8_t)(nwid >> 24);
  408. sin6->sin6_addr.s6_addr[2] = (uint8_t)(nwid >> 16);
  409. sin6->sin6_addr.s6_addr[3] = (uint8_t)(nwid >> 8);
  410. sin6->sin6_addr.s6_addr[4] = (uint8_t)nwid;
  411. sin6->sin6_addr.s6_addr[5] = (uint8_t)(zeroTierAddress >> 32);
  412. sin6->sin6_addr.s6_addr[6] = (uint8_t)(zeroTierAddress >> 24);
  413. sin6->sin6_addr.s6_addr[7] = (uint8_t)(zeroTierAddress >> 16);
  414. sin6->sin6_addr.s6_addr[8] = (uint8_t)(zeroTierAddress >> 8);
  415. sin6->sin6_addr.s6_addr[9] = (uint8_t)zeroTierAddress;
  416. sin6->sin6_addr.s6_addr[15] = 0x01;
  417. sin6->sin6_port = Utils::hton((uint16_t)40);
  418. return r;
  419. }
  420. } // namespace ZeroTier