netaddress.cpp raw
1 // Copyright (c) 2009-2010 Satoshi Nakamoto
2 // Copyright (c) 2009-present The Bitcoin Core developers
3 // Distributed under the MIT software license, see the accompanying
4 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
5
6 #include <netaddress.h>
7
8 #include <crypto/common.h>
9 #include <crypto/sha3.h>
10 #include <hash.h>
11 #include <prevector.h>
12 #include <tinyformat.h>
13 #include <util/strencodings.h>
14 #include <util/string.h>
15
16 #include <algorithm>
17 #include <array>
18 #include <cstdint>
19 #include <ios>
20 #include <iterator>
21 #include <string_view>
22 #include <tuple>
23
24 using util::ContainsNoNUL;
25 using util::HasPrefix;
26
27 CNetAddr::BIP155Network CNetAddr::GetBIP155Network() const
28 {
29 switch (m_net) {
30 case NET_IPV4:
31 return BIP155Network::IPV4;
32 case NET_IPV6:
33 return BIP155Network::IPV6;
34 case NET_ONION:
35 return BIP155Network::TORV3;
36 case NET_I2P:
37 return BIP155Network::I2P;
38 case NET_CJDNS:
39 return BIP155Network::CJDNS;
40 case NET_INTERNAL: // should have been handled before calling this function
41 case NET_UNROUTABLE: // m_net is never and should not be set to NET_UNROUTABLE
42 case NET_MAX: // m_net is never and should not be set to NET_MAX
43 assert(false);
44 } // no default case, so the compiler can warn about missing cases
45
46 assert(false);
47 }
48
49 bool CNetAddr::SetNetFromBIP155Network(uint8_t possible_bip155_net, size_t address_size)
50 {
51 switch (possible_bip155_net) {
52 case BIP155Network::IPV4:
53 if (address_size == ADDR_IPV4_SIZE) {
54 m_net = NET_IPV4;
55 return true;
56 }
57 throw std::ios_base::failure(
58 strprintf("BIP155 IPv4 address with length %u (should be %u)", address_size,
59 ADDR_IPV4_SIZE));
60 case BIP155Network::IPV6:
61 if (address_size == ADDR_IPV6_SIZE) {
62 m_net = NET_IPV6;
63 return true;
64 }
65 throw std::ios_base::failure(
66 strprintf("BIP155 IPv6 address with length %u (should be %u)", address_size,
67 ADDR_IPV6_SIZE));
68 case BIP155Network::TORV3:
69 if (address_size == ADDR_TORV3_SIZE) {
70 m_net = NET_ONION;
71 return true;
72 }
73 throw std::ios_base::failure(
74 strprintf("BIP155 TORv3 address with length %u (should be %u)", address_size,
75 ADDR_TORV3_SIZE));
76 case BIP155Network::I2P:
77 if (address_size == ADDR_I2P_SIZE) {
78 m_net = NET_I2P;
79 return true;
80 }
81 throw std::ios_base::failure(
82 strprintf("BIP155 I2P address with length %u (should be %u)", address_size,
83 ADDR_I2P_SIZE));
84 case BIP155Network::CJDNS:
85 if (address_size == ADDR_CJDNS_SIZE) {
86 m_net = NET_CJDNS;
87 return true;
88 }
89 throw std::ios_base::failure(
90 strprintf("BIP155 CJDNS address with length %u (should be %u)", address_size,
91 ADDR_CJDNS_SIZE));
92 }
93
94 // Don't throw on addresses with unknown network ids (maybe from the future).
95 // Instead silently drop them and have the unserialization code consume
96 // subsequent ones which may be known to us.
97 return false;
98 }
99
100 /**
101 * Construct an unspecified IPv6 network address (::/128).
102 *
103 * @note This address is considered invalid by CNetAddr::IsValid()
104 */
105 CNetAddr::CNetAddr() = default;
106
107 void CNetAddr::SetIP(const CNetAddr& ipIn)
108 {
109 // Size check.
110 switch (ipIn.m_net) {
111 case NET_IPV4:
112 assert(ipIn.m_addr.size() == ADDR_IPV4_SIZE);
113 break;
114 case NET_IPV6:
115 assert(ipIn.m_addr.size() == ADDR_IPV6_SIZE);
116 break;
117 case NET_ONION:
118 assert(ipIn.m_addr.size() == ADDR_TORV3_SIZE);
119 break;
120 case NET_I2P:
121 assert(ipIn.m_addr.size() == ADDR_I2P_SIZE);
122 break;
123 case NET_CJDNS:
124 assert(ipIn.m_addr.size() == ADDR_CJDNS_SIZE);
125 break;
126 case NET_INTERNAL:
127 assert(ipIn.m_addr.size() == ADDR_INTERNAL_SIZE);
128 break;
129 case NET_UNROUTABLE:
130 case NET_MAX:
131 assert(false);
132 } // no default case, so the compiler can warn about missing cases
133
134 m_net = ipIn.m_net;
135 m_addr = ipIn.m_addr;
136 }
137
138 void CNetAddr::SetLegacyIPv6(std::span<const uint8_t> ipv6)
139 {
140 assert(ipv6.size() == ADDR_IPV6_SIZE);
141
142 size_t skip{0};
143
144 if (HasPrefix(ipv6, IPV4_IN_IPV6_PREFIX)) {
145 // IPv4-in-IPv6
146 m_net = NET_IPV4;
147 skip = sizeof(IPV4_IN_IPV6_PREFIX);
148 } else if (HasPrefix(ipv6, TORV2_IN_IPV6_PREFIX)) {
149 // TORv2-in-IPv6 (unsupported). Unserialize as !IsValid(), thus ignoring them.
150 // Mimic a default-constructed CNetAddr object which is !IsValid() and thus
151 // will not be gossiped, but continue reading next addresses from the stream.
152 m_net = NET_IPV6;
153 m_addr.assign(ADDR_IPV6_SIZE, 0x0);
154 return;
155 } else if (HasPrefix(ipv6, INTERNAL_IN_IPV6_PREFIX)) {
156 // Internal-in-IPv6
157 m_net = NET_INTERNAL;
158 skip = sizeof(INTERNAL_IN_IPV6_PREFIX);
159 } else {
160 // IPv6
161 m_net = NET_IPV6;
162 }
163
164 m_addr.assign(ipv6.begin() + skip, ipv6.end());
165 }
166
167 /**
168 * Create an "internal" address that represents a name or FQDN. AddrMan uses
169 * these fake addresses to keep track of which DNS seeds were used.
170 * @returns Whether or not the operation was successful.
171 * @see NET_INTERNAL, INTERNAL_IN_IPV6_PREFIX, CNetAddr::IsInternal(), CNetAddr::IsRFC4193()
172 */
173 bool CNetAddr::SetInternal(const std::string &name)
174 {
175 if (name.empty()) {
176 return false;
177 }
178 m_net = NET_INTERNAL;
179 unsigned char hash[32] = {};
180 CSHA256().Write((const unsigned char*)name.data(), name.size()).Finalize(hash);
181 m_addr.assign(hash, hash + ADDR_INTERNAL_SIZE);
182 return true;
183 }
184
185 namespace torv3 {
186 // https://gitlab.torproject.org/tpo/core/torspec/-/tree/main/spec/rend-spec
187 static constexpr size_t CHECKSUM_LEN = 2;
188 static const unsigned char VERSION[] = {3};
189 static constexpr size_t TOTAL_LEN = ADDR_TORV3_SIZE + CHECKSUM_LEN + sizeof(VERSION);
190
191 static void Checksum(std::span<const uint8_t> addr_pubkey, uint8_t (&checksum)[CHECKSUM_LEN])
192 {
193 // TORv3 CHECKSUM = H(".onion checksum" | PUBKEY | VERSION)[:2]
194 static const unsigned char prefix[] = ".onion checksum";
195 static constexpr size_t prefix_len = 15;
196
197 SHA3_256 hasher;
198
199 hasher.Write(std::span{prefix}.first(prefix_len));
200 hasher.Write(addr_pubkey);
201 hasher.Write(VERSION);
202
203 uint8_t checksum_full[SHA3_256::OUTPUT_SIZE];
204
205 hasher.Finalize(checksum_full);
206
207 memcpy(checksum, checksum_full, sizeof(checksum));
208 }
209
210 }; // namespace torv3
211
212 bool CNetAddr::SetSpecial(std::string_view addr)
213 {
214 if (!ContainsNoNUL(addr)) {
215 return false;
216 }
217
218 if (SetTor(addr)) {
219 return true;
220 }
221
222 if (SetI2P(addr)) {
223 return true;
224 }
225
226 return false;
227 }
228
229 bool CNetAddr::SetTor(std::string_view addr)
230 {
231 if (!addr.ends_with(".onion")) return false;
232 addr.remove_suffix(6);
233 auto input = DecodeBase32(addr);
234
235 if (!input) {
236 return false;
237 }
238
239 if (input->size() == torv3::TOTAL_LEN) {
240 std::span<const uint8_t> input_pubkey{input->data(), ADDR_TORV3_SIZE};
241 std::span<const uint8_t> input_checksum{input->data() + ADDR_TORV3_SIZE, torv3::CHECKSUM_LEN};
242 std::span<const uint8_t> input_version{input->data() + ADDR_TORV3_SIZE + torv3::CHECKSUM_LEN, sizeof(torv3::VERSION)};
243
244 if (!std::ranges::equal(input_version, torv3::VERSION)) {
245 return false;
246 }
247
248 uint8_t calculated_checksum[torv3::CHECKSUM_LEN];
249 torv3::Checksum(input_pubkey, calculated_checksum);
250
251 if (!std::ranges::equal(input_checksum, calculated_checksum)) {
252 return false;
253 }
254
255 m_net = NET_ONION;
256 m_addr.assign(input_pubkey.begin(), input_pubkey.end());
257 return true;
258 }
259
260 return false;
261 }
262
263 bool CNetAddr::SetI2P(std::string_view addr)
264 {
265 // I2P addresses that we support consist of 52 base32 characters + ".b32.i2p".
266 static constexpr size_t b32_len{52};
267 static const char* suffix{".b32.i2p"};
268 static constexpr size_t suffix_len{8};
269
270 if (addr.size() != b32_len + suffix_len || ToLower(addr.substr(b32_len)) != suffix) {
271 return false;
272 }
273
274 // Remove the ".b32.i2p" suffix and pad to a multiple of 8 chars, so DecodeBase32()
275 // can decode it.
276 const std::string b32_padded{tfm::format("%s====", addr.substr(0, b32_len))};
277
278 auto address_bytes = DecodeBase32(b32_padded);
279
280 if (!address_bytes || address_bytes->size() != ADDR_I2P_SIZE) {
281 return false;
282 }
283
284 m_net = NET_I2P;
285 m_addr.assign(address_bytes->begin(), address_bytes->end());
286
287 return true;
288 }
289
290 CNetAddr::CNetAddr(const struct in_addr& ipv4Addr)
291 {
292 m_net = NET_IPV4;
293 const uint8_t* ptr = reinterpret_cast<const uint8_t*>(&ipv4Addr);
294 m_addr.assign(ptr, ptr + ADDR_IPV4_SIZE);
295 }
296
297 CNetAddr::CNetAddr(const struct in6_addr& ipv6Addr, const uint32_t scope)
298 {
299 SetLegacyIPv6({reinterpret_cast<const uint8_t*>(&ipv6Addr), sizeof(ipv6Addr)});
300 m_scope_id = scope;
301 }
302
303 bool CNetAddr::IsBindAny() const
304 {
305 if (!IsIPv4() && !IsIPv6()) {
306 return false;
307 }
308 return std::all_of(m_addr.begin(), m_addr.end(), [](uint8_t b) { return b == 0; });
309 }
310
311 bool CNetAddr::IsRFC1918() const
312 {
313 return IsIPv4() && (
314 m_addr[0] == 10 ||
315 (m_addr[0] == 192 && m_addr[1] == 168) ||
316 (m_addr[0] == 172 && m_addr[1] >= 16 && m_addr[1] <= 31));
317 }
318
319 bool CNetAddr::IsRFC2544() const
320 {
321 return IsIPv4() && m_addr[0] == 198 && (m_addr[1] == 18 || m_addr[1] == 19);
322 }
323
324 bool CNetAddr::IsRFC3927() const
325 {
326 return IsIPv4() && HasPrefix(m_addr, std::array<uint8_t, 2>{169, 254});
327 }
328
329 bool CNetAddr::IsRFC6598() const
330 {
331 return IsIPv4() && m_addr[0] == 100 && m_addr[1] >= 64 && m_addr[1] <= 127;
332 }
333
334 bool CNetAddr::IsRFC5737() const
335 {
336 return IsIPv4() && (HasPrefix(m_addr, std::array<uint8_t, 3>{192, 0, 2}) ||
337 HasPrefix(m_addr, std::array<uint8_t, 3>{198, 51, 100}) ||
338 HasPrefix(m_addr, std::array<uint8_t, 3>{203, 0, 113}));
339 }
340
341 bool CNetAddr::IsRFC3849() const
342 {
343 return IsIPv6() && HasPrefix(m_addr, std::array<uint8_t, 4>{0x20, 0x01, 0x0D, 0xB8});
344 }
345
346 bool CNetAddr::IsRFC3964() const
347 {
348 return IsIPv6() && HasPrefix(m_addr, std::array<uint8_t, 2>{0x20, 0x02});
349 }
350
351 bool CNetAddr::IsRFC6052() const
352 {
353 return IsIPv6() &&
354 HasPrefix(m_addr, std::array<uint8_t, 12>{0x00, 0x64, 0xFF, 0x9B, 0x00, 0x00,
355 0x00, 0x00, 0x00, 0x00, 0x00, 0x00});
356 }
357
358 bool CNetAddr::IsRFC4380() const
359 {
360 return IsIPv6() && HasPrefix(m_addr, std::array<uint8_t, 4>{0x20, 0x01, 0x00, 0x00});
361 }
362
363 bool CNetAddr::IsRFC4862() const
364 {
365 return IsIPv6() && HasPrefix(m_addr, std::array<uint8_t, 8>{0xFE, 0x80, 0x00, 0x00,
366 0x00, 0x00, 0x00, 0x00});
367 }
368
369 bool CNetAddr::IsRFC4193() const
370 {
371 return IsIPv6() && (m_addr[0] & 0xFE) == 0xFC;
372 }
373
374 bool CNetAddr::IsRFC6145() const
375 {
376 return IsIPv6() &&
377 HasPrefix(m_addr, std::array<uint8_t, 12>{0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
378 0x00, 0x00, 0xFF, 0xFF, 0x00, 0x00});
379 }
380
381 bool CNetAddr::IsRFC4843() const
382 {
383 return IsIPv6() && HasPrefix(m_addr, std::array<uint8_t, 3>{0x20, 0x01, 0x00}) &&
384 (m_addr[3] & 0xF0) == 0x10;
385 }
386
387 bool CNetAddr::IsRFC7343() const
388 {
389 return IsIPv6() && HasPrefix(m_addr, std::array<uint8_t, 3>{0x20, 0x01, 0x00}) &&
390 (m_addr[3] & 0xF0) == 0x20;
391 }
392
393 bool CNetAddr::IsHeNet() const
394 {
395 return IsIPv6() && HasPrefix(m_addr, std::array<uint8_t, 4>{0x20, 0x01, 0x04, 0x70});
396 }
397
398 bool CNetAddr::IsLocal() const
399 {
400 // IPv4 loopback (127.0.0.0/8 or 0.0.0.0/8)
401 if (IsIPv4() && (m_addr[0] == 127 || m_addr[0] == 0)) {
402 return true;
403 }
404
405 // IPv6 loopback (::1/128)
406 static const unsigned char pchLocal[16] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1};
407 if (IsIPv6() && memcmp(m_addr.data(), pchLocal, sizeof(pchLocal)) == 0) {
408 return true;
409 }
410
411 return false;
412 }
413
414 /**
415 * @returns Whether or not this network address is a valid address that @a could
416 * be used to refer to an actual host.
417 *
418 * @note A valid address may or may not be publicly routable on the global
419 * internet. As in, the set of valid addresses is a superset of the set of
420 * publicly routable addresses.
421 *
422 * @see CNetAddr::IsRoutable()
423 */
424 bool CNetAddr::IsValid() const
425 {
426 // unspecified IPv6 address (::/128)
427 unsigned char ipNone6[16] = {};
428 if (IsIPv6() && memcmp(m_addr.data(), ipNone6, sizeof(ipNone6)) == 0) {
429 return false;
430 }
431
432 if (IsCJDNS() && !HasCJDNSPrefix()) {
433 return false;
434 }
435
436 // documentation IPv6 address
437 if (IsRFC3849())
438 return false;
439
440 if (IsInternal())
441 return false;
442
443 if (IsIPv4()) {
444 const uint32_t addr = ReadBE32(m_addr.data());
445 if (addr == INADDR_ANY || addr == INADDR_NONE) {
446 return false;
447 }
448 }
449
450 return true;
451 }
452
453 /**
454 * @returns Whether or not this network address is publicly routable on the
455 * global internet.
456 *
457 * @note A routable address is always valid. As in, the set of routable addresses
458 * is a subset of the set of valid addresses.
459 *
460 * @see CNetAddr::IsValid()
461 */
462 bool CNetAddr::IsRoutable() const
463 {
464 return IsValid() && !(IsRFC1918() || IsRFC2544() || IsRFC3927() || IsRFC4862() || IsRFC6598() || IsRFC5737() || IsRFC4193() || IsRFC4843() || IsRFC7343() || IsLocal() || IsInternal());
465 }
466
467 /**
468 * @returns Whether or not this is a dummy address that represents a name.
469 *
470 * @see CNetAddr::SetInternal(const std::string &)
471 */
472 bool CNetAddr::IsInternal() const
473 {
474 return m_net == NET_INTERNAL;
475 }
476
477 bool CNetAddr::IsAddrV1Compatible() const
478 {
479 switch (m_net) {
480 case NET_IPV4:
481 case NET_IPV6:
482 case NET_INTERNAL:
483 return true;
484 case NET_ONION:
485 case NET_I2P:
486 case NET_CJDNS:
487 return false;
488 case NET_UNROUTABLE: // m_net is never and should not be set to NET_UNROUTABLE
489 case NET_MAX: // m_net is never and should not be set to NET_MAX
490 assert(false);
491 } // no default case, so the compiler can warn about missing cases
492
493 assert(false);
494 }
495
496 enum Network CNetAddr::GetNetwork() const
497 {
498 if (IsInternal())
499 return NET_INTERNAL;
500
501 if (!IsRoutable())
502 return NET_UNROUTABLE;
503
504 return m_net;
505 }
506
507 static std::string IPv4ToString(std::span<const uint8_t> a)
508 {
509 return strprintf("%u.%u.%u.%u", a[0], a[1], a[2], a[3]);
510 }
511
512 // Return an IPv6 address text representation with zero compression as described in RFC 5952
513 // ("A Recommendation for IPv6 Address Text Representation").
514 static std::string IPv6ToString(std::span<const uint8_t> a, uint32_t scope_id)
515 {
516 assert(a.size() == ADDR_IPV6_SIZE);
517 const std::array groups{
518 ReadBE16(&a[0]),
519 ReadBE16(&a[2]),
520 ReadBE16(&a[4]),
521 ReadBE16(&a[6]),
522 ReadBE16(&a[8]),
523 ReadBE16(&a[10]),
524 ReadBE16(&a[12]),
525 ReadBE16(&a[14]),
526 };
527
528 // The zero compression implementation is inspired by Rust's std::net::Ipv6Addr, see
529 // https://github.com/rust-lang/rust/blob/cc4103089f40a163f6d143f06359cba7043da29b/library/std/src/net/ip.rs#L1635-L1683
530 struct ZeroSpan {
531 size_t start_index{0};
532 size_t len{0};
533 };
534
535 // Find longest sequence of consecutive all-zero fields. Use first zero sequence if two or more
536 // zero sequences of equal length are found.
537 ZeroSpan longest, current;
538 for (size_t i{0}; i < groups.size(); ++i) {
539 if (groups[i] != 0) {
540 current = {i + 1, 0};
541 continue;
542 }
543 current.len += 1;
544 if (current.len > longest.len) {
545 longest = current;
546 }
547 }
548
549 std::string r;
550 r.reserve(39);
551 for (size_t i{0}; i < groups.size(); ++i) {
552 // Replace the longest sequence of consecutive all-zero fields with two colons ("::").
553 if (longest.len >= 2 && i >= longest.start_index && i < longest.start_index + longest.len) {
554 if (i == longest.start_index) {
555 r += "::";
556 }
557 continue;
558 }
559 r += strprintf("%s%x", ((!r.empty() && r.back() != ':') ? ":" : ""), groups[i]);
560 }
561
562 if (scope_id != 0) {
563 r += strprintf("%%%u", scope_id);
564 }
565
566 return r;
567 }
568
569 std::string OnionToString(std::span<const uint8_t> addr)
570 {
571 uint8_t checksum[torv3::CHECKSUM_LEN];
572 torv3::Checksum(addr, checksum);
573 // TORv3 onion_address = base32(PUBKEY | CHECKSUM | VERSION) + ".onion"
574 prevector<torv3::TOTAL_LEN, uint8_t> address{addr.begin(), addr.end()};
575 address.insert(address.end(), checksum, checksum + torv3::CHECKSUM_LEN);
576 address.insert(address.end(), torv3::VERSION, torv3::VERSION + sizeof(torv3::VERSION));
577 return EncodeBase32(address) + ".onion";
578 }
579
580 std::string CNetAddr::ToStringAddr() const
581 {
582 switch (m_net) {
583 case NET_IPV4:
584 return IPv4ToString(m_addr);
585 case NET_IPV6:
586 return IPv6ToString(m_addr, m_scope_id);
587 case NET_ONION:
588 return OnionToString(m_addr);
589 case NET_I2P:
590 return EncodeBase32(m_addr, false /* don't pad with = */) + ".b32.i2p";
591 case NET_CJDNS:
592 return IPv6ToString(m_addr, 0);
593 case NET_INTERNAL:
594 return EncodeBase32(m_addr) + ".internal";
595 case NET_UNROUTABLE: // m_net is never and should not be set to NET_UNROUTABLE
596 case NET_MAX: // m_net is never and should not be set to NET_MAX
597 assert(false);
598 } // no default case, so the compiler can warn about missing cases
599
600 assert(false);
601 }
602
603 bool operator==(const CNetAddr& a, const CNetAddr& b)
604 {
605 return a.m_net == b.m_net && a.m_addr == b.m_addr;
606 }
607
608 bool operator<(const CNetAddr& a, const CNetAddr& b)
609 {
610 return std::tie(a.m_net, a.m_addr) < std::tie(b.m_net, b.m_addr);
611 }
612
613 /**
614 * Try to get our IPv4 address.
615 *
616 * @param[out] pipv4Addr The in_addr struct to which to copy.
617 *
618 * @returns Whether or not the operation was successful, in particular, whether
619 * or not our address was an IPv4 address.
620 *
621 * @see CNetAddr::IsIPv4()
622 */
623 bool CNetAddr::GetInAddr(struct in_addr* pipv4Addr) const
624 {
625 if (!IsIPv4())
626 return false;
627 assert(sizeof(*pipv4Addr) == m_addr.size());
628 memcpy(pipv4Addr, m_addr.data(), m_addr.size());
629 return true;
630 }
631
632 /**
633 * Try to get our IPv6 (or CJDNS) address.
634 *
635 * @param[out] pipv6Addr The in6_addr struct to which to copy.
636 *
637 * @returns Whether or not the operation was successful, in particular, whether
638 * or not our address was an IPv6 address.
639 *
640 * @see CNetAddr::IsIPv6()
641 */
642 bool CNetAddr::GetIn6Addr(struct in6_addr* pipv6Addr) const
643 {
644 if (!IsIPv6() && !IsCJDNS()) {
645 return false;
646 }
647 assert(sizeof(*pipv6Addr) == m_addr.size());
648 memcpy(pipv6Addr, m_addr.data(), m_addr.size());
649 return true;
650 }
651
652 bool CNetAddr::HasLinkedIPv4() const
653 {
654 return IsRoutable() && (IsIPv4() || IsRFC6145() || IsRFC6052() || IsRFC3964() || IsRFC4380());
655 }
656
657 uint32_t CNetAddr::GetLinkedIPv4() const
658 {
659 if (IsIPv4()) {
660 return ReadBE32(m_addr.data());
661 } else if (IsRFC6052() || IsRFC6145()) {
662 // mapped IPv4, SIIT translated IPv4: the IPv4 address is the last 4 bytes of the address
663 return ReadBE32(std::span{m_addr}.last(ADDR_IPV4_SIZE).data());
664 } else if (IsRFC3964()) {
665 // 6to4 tunneled IPv4: the IPv4 address is in bytes 2-6
666 return ReadBE32(std::span{m_addr}.subspan(2, ADDR_IPV4_SIZE).data());
667 } else if (IsRFC4380()) {
668 // Teredo tunneled IPv4: the IPv4 address is in the last 4 bytes of the address, but bitflipped
669 return ~ReadBE32(std::span{m_addr}.last(ADDR_IPV4_SIZE).data());
670 }
671 assert(false);
672 }
673
674 Network CNetAddr::GetNetClass() const
675 {
676 // Make sure that if we return NET_IPV6, then IsIPv6() is true. The callers expect that.
677
678 // Check for "internal" first because such addresses are also !IsRoutable()
679 // and we don't want to return NET_UNROUTABLE in that case.
680 if (IsInternal()) {
681 return NET_INTERNAL;
682 }
683 if (!IsRoutable()) {
684 return NET_UNROUTABLE;
685 }
686 if (HasLinkedIPv4()) {
687 return NET_IPV4;
688 }
689 return m_net;
690 }
691
692 std::vector<unsigned char> CNetAddr::GetAddrBytes() const
693 {
694 if (IsAddrV1Compatible()) {
695 uint8_t serialized[V1_SERIALIZATION_SIZE];
696 SerializeV1Array(serialized);
697 return {std::begin(serialized), std::end(serialized)};
698 }
699 return std::vector<unsigned char>(m_addr.begin(), m_addr.end());
700 }
701
702 // private extensions to enum Network, only returned by GetExtNetwork,
703 // and only used in GetReachabilityFrom
704 static const int NET_TEREDO = NET_MAX;
705 int static GetExtNetwork(const CNetAddr& addr)
706 {
707 if (addr.IsRFC4380())
708 return NET_TEREDO;
709 return addr.GetNetwork();
710 }
711
712 /** Calculates a metric for how reachable (*this) is from a given partner */
713 int CNetAddr::GetReachabilityFrom(const CNetAddr& paddrPartner) const
714 {
715 enum Reachability {
716 REACH_UNREACHABLE,
717 REACH_DEFAULT,
718 REACH_TEREDO,
719 REACH_IPV6_WEAK,
720 REACH_IPV4,
721 REACH_IPV6_STRONG,
722 REACH_PRIVATE
723 };
724
725 if (!IsRoutable() || IsInternal())
726 return REACH_UNREACHABLE;
727
728 int ourNet = GetExtNetwork(*this);
729 int theirNet = GetExtNetwork(paddrPartner);
730 bool fTunnel = IsRFC3964() || IsRFC6052() || IsRFC6145();
731
732 switch(theirNet) {
733 case NET_IPV4:
734 switch(ourNet) {
735 default: return REACH_DEFAULT;
736 case NET_IPV4: return REACH_IPV4;
737 }
738 case NET_IPV6:
739 switch(ourNet) {
740 default: return REACH_DEFAULT;
741 case NET_TEREDO: return REACH_TEREDO;
742 case NET_IPV4: return REACH_IPV4;
743 case NET_IPV6: return fTunnel ? REACH_IPV6_WEAK : REACH_IPV6_STRONG; // only prefer giving our IPv6 address if it's not tunnelled
744 }
745 case NET_ONION:
746 switch(ourNet) {
747 default: return REACH_DEFAULT;
748 case NET_IPV4: return REACH_IPV4; // Tor users can connect to IPv4 as well
749 case NET_ONION: return REACH_PRIVATE;
750 }
751 case NET_I2P:
752 switch (ourNet) {
753 case NET_I2P: return REACH_PRIVATE;
754 default: return REACH_DEFAULT;
755 }
756 case NET_CJDNS:
757 switch (ourNet) {
758 case NET_CJDNS: return REACH_PRIVATE;
759 default: return REACH_DEFAULT;
760 }
761 case NET_TEREDO:
762 switch(ourNet) {
763 default: return REACH_DEFAULT;
764 case NET_TEREDO: return REACH_TEREDO;
765 case NET_IPV6: return REACH_IPV6_WEAK;
766 case NET_IPV4: return REACH_IPV4;
767 }
768 case NET_UNROUTABLE:
769 default:
770 switch(ourNet) {
771 default: return REACH_DEFAULT;
772 case NET_TEREDO: return REACH_TEREDO;
773 case NET_IPV6: return REACH_IPV6_WEAK;
774 case NET_IPV4: return REACH_IPV4;
775 case NET_ONION: return REACH_PRIVATE; // either from Tor, or don't care about our address
776 }
777 }
778 }
779
780 CService::CService() : port(0)
781 {
782 }
783
784 CService::CService(const CNetAddr& cip, uint16_t portIn) : CNetAddr(cip), port(portIn)
785 {
786 }
787
788 CService::CService(const struct in_addr& ipv4Addr, uint16_t portIn) : CNetAddr(ipv4Addr), port(portIn)
789 {
790 }
791
792 CService::CService(const struct in6_addr& ipv6Addr, uint16_t portIn) : CNetAddr(ipv6Addr), port(portIn)
793 {
794 }
795
796 CService::CService(const struct sockaddr_in& addr) : CNetAddr(addr.sin_addr), port(ntohs(addr.sin_port))
797 {
798 assert(addr.sin_family == AF_INET);
799 }
800
801 CService::CService(const struct sockaddr_in6 &addr) : CNetAddr(addr.sin6_addr, addr.sin6_scope_id), port(ntohs(addr.sin6_port))
802 {
803 assert(addr.sin6_family == AF_INET6);
804 }
805
806 bool CService::SetSockAddr(const struct sockaddr *paddr, socklen_t addrlen)
807 {
808 switch (paddr->sa_family) {
809 case AF_INET:
810 if (addrlen != sizeof(struct sockaddr_in)) return false;
811 *this = CService(*(const struct sockaddr_in*)paddr);
812 return true;
813 case AF_INET6:
814 if (addrlen != sizeof(struct sockaddr_in6)) return false;
815 *this = CService(*(const struct sockaddr_in6*)paddr);
816 return true;
817 default:
818 return false;
819 }
820 }
821
822 sa_family_t CService::GetSAFamily() const
823 {
824 switch (m_net) {
825 case NET_IPV4:
826 return AF_INET;
827 case NET_IPV6:
828 case NET_CJDNS:
829 return AF_INET6;
830 default:
831 return AF_UNSPEC;
832 }
833 }
834
835 uint16_t CService::GetPort() const
836 {
837 return port;
838 }
839
840 bool operator==(const CService& a, const CService& b)
841 {
842 return static_cast<CNetAddr>(a) == static_cast<CNetAddr>(b) && a.port == b.port;
843 }
844
845 bool operator<(const CService& a, const CService& b)
846 {
847 return static_cast<CNetAddr>(a) < static_cast<CNetAddr>(b) || (static_cast<CNetAddr>(a) == static_cast<CNetAddr>(b) && a.port < b.port);
848 }
849
850 /**
851 * Obtain the IPv4/6 socket address this represents.
852 *
853 * @param[out] paddr The obtained socket address.
854 * @param[in,out] addrlen The size, in bytes, of the address structure pointed
855 * to by paddr. The value that's pointed to by this
856 * parameter might change after calling this function if
857 * the size of the corresponding address structure
858 * changed.
859 *
860 * @returns Whether or not the operation was successful.
861 */
862 bool CService::GetSockAddr(struct sockaddr* paddr, socklen_t *addrlen) const
863 {
864 if (IsIPv4()) {
865 if (*addrlen < (socklen_t)sizeof(struct sockaddr_in))
866 return false;
867 *addrlen = sizeof(struct sockaddr_in);
868 struct sockaddr_in *paddrin = (struct sockaddr_in*)paddr;
869 memset(paddrin, 0, *addrlen);
870 if (!GetInAddr(&paddrin->sin_addr))
871 return false;
872 paddrin->sin_family = AF_INET;
873 paddrin->sin_port = htons(port);
874 return true;
875 }
876 if (IsIPv6() || IsCJDNS()) {
877 if (*addrlen < (socklen_t)sizeof(struct sockaddr_in6))
878 return false;
879 *addrlen = sizeof(struct sockaddr_in6);
880 struct sockaddr_in6 *paddrin6 = (struct sockaddr_in6*)paddr;
881 memset(paddrin6, 0, *addrlen);
882 if (!GetIn6Addr(&paddrin6->sin6_addr))
883 return false;
884 paddrin6->sin6_scope_id = m_scope_id;
885 paddrin6->sin6_family = AF_INET6;
886 paddrin6->sin6_port = htons(port);
887 return true;
888 }
889 return false;
890 }
891
892 /**
893 * @returns An identifier unique to this service's address and port number.
894 */
895 std::vector<unsigned char> CService::GetKey() const
896 {
897 auto key = GetAddrBytes();
898 key.push_back(port / 0x100); // most significant byte of our port
899 key.push_back(port & 0x0FF); // least significant byte of our port
900 return key;
901 }
902
903 std::string CService::ToStringAddrPort() const
904 {
905 const auto port_str = strprintf("%u", port);
906
907 if (IsIPv4() || IsTor() || IsI2P() || IsInternal()) {
908 return ToStringAddr() + ":" + port_str;
909 } else {
910 return "[" + ToStringAddr() + "]:" + port_str;
911 }
912 }
913
914 CSubNet::CSubNet():
915 valid(false)
916 {
917 memset(netmask, 0, sizeof(netmask));
918 }
919
920 CSubNet::CSubNet(const CNetAddr& addr, uint8_t mask) : CSubNet()
921 {
922 valid = (addr.IsIPv4() && mask <= ADDR_IPV4_SIZE * 8) ||
923 (addr.IsIPv6() && mask <= ADDR_IPV6_SIZE * 8);
924 if (!valid) {
925 return;
926 }
927
928 assert(mask <= sizeof(netmask) * 8);
929
930 network = addr;
931
932 uint8_t n = mask;
933 for (size_t i = 0; i < network.m_addr.size(); ++i) {
934 const uint8_t bits = n < 8 ? n : 8;
935 netmask[i] = (uint8_t)((uint8_t)0xFF << (8 - bits)); // Set first bits.
936 network.m_addr[i] &= netmask[i]; // Normalize network according to netmask.
937 n -= bits;
938 }
939 }
940
941 /**
942 * @returns The number of 1-bits in the prefix of the specified subnet mask. If
943 * the specified subnet mask is not a valid one, -1.
944 */
945 static inline int NetmaskBits(uint8_t x)
946 {
947 switch(x) {
948 case 0x00: return 0;
949 case 0x80: return 1;
950 case 0xc0: return 2;
951 case 0xe0: return 3;
952 case 0xf0: return 4;
953 case 0xf8: return 5;
954 case 0xfc: return 6;
955 case 0xfe: return 7;
956 case 0xff: return 8;
957 default: return -1;
958 }
959 }
960
961 CSubNet::CSubNet(const CNetAddr& addr, const CNetAddr& mask) : CSubNet()
962 {
963 valid = (addr.IsIPv4() || addr.IsIPv6()) && addr.m_net == mask.m_net;
964 if (!valid) {
965 return;
966 }
967 // Check if `mask` contains 1-bits after 0-bits (which is an invalid netmask).
968 bool zeros_found = false;
969 for (auto b : mask.m_addr) {
970 const int num_bits = NetmaskBits(b);
971 if (num_bits == -1 || (zeros_found && num_bits != 0)) {
972 valid = false;
973 return;
974 }
975 if (num_bits < 8) {
976 zeros_found = true;
977 }
978 }
979
980 assert(mask.m_addr.size() <= sizeof(netmask));
981
982 memcpy(netmask, mask.m_addr.data(), mask.m_addr.size());
983
984 network = addr;
985
986 // Normalize network according to netmask
987 for (size_t x = 0; x < network.m_addr.size(); ++x) {
988 network.m_addr[x] &= netmask[x];
989 }
990 }
991
992 CSubNet::CSubNet(const CNetAddr& addr) : CSubNet()
993 {
994 switch (addr.m_net) {
995 case NET_IPV4:
996 case NET_IPV6:
997 valid = true;
998 assert(addr.m_addr.size() <= sizeof(netmask));
999 memset(netmask, 0xFF, addr.m_addr.size());
1000 break;
1001 case NET_ONION:
1002 case NET_I2P:
1003 case NET_CJDNS:
1004 valid = true;
1005 break;
1006 case NET_INTERNAL:
1007 case NET_UNROUTABLE:
1008 case NET_MAX:
1009 return;
1010 }
1011
1012 network = addr;
1013 }
1014
1015 /**
1016 * @returns True if this subnet is valid, the specified address is valid, and
1017 * the specified address belongs in this subnet.
1018 */
1019 bool CSubNet::Match(const CNetAddr &addr) const
1020 {
1021 if (!valid || !addr.IsValid() || network.m_net != addr.m_net)
1022 return false;
1023
1024 switch (network.m_net) {
1025 case NET_IPV4:
1026 case NET_IPV6:
1027 break;
1028 case NET_ONION:
1029 case NET_I2P:
1030 case NET_CJDNS:
1031 case NET_INTERNAL:
1032 return addr == network;
1033 case NET_UNROUTABLE:
1034 case NET_MAX:
1035 return false;
1036 }
1037
1038 assert(network.m_addr.size() == addr.m_addr.size());
1039 for (size_t x = 0; x < addr.m_addr.size(); ++x) {
1040 if ((addr.m_addr[x] & netmask[x]) != network.m_addr[x]) {
1041 return false;
1042 }
1043 }
1044 return true;
1045 }
1046
1047 std::string CSubNet::ToString() const
1048 {
1049 std::string suffix;
1050
1051 switch (network.m_net) {
1052 case NET_IPV4:
1053 case NET_IPV6: {
1054 assert(network.m_addr.size() <= sizeof(netmask));
1055
1056 uint8_t cidr = 0;
1057
1058 for (size_t i = 0; i < network.m_addr.size(); ++i) {
1059 if (netmask[i] == 0x00) {
1060 break;
1061 }
1062 cidr += NetmaskBits(netmask[i]);
1063 }
1064
1065 suffix = strprintf("/%u", cidr);
1066 break;
1067 }
1068 case NET_ONION:
1069 case NET_I2P:
1070 case NET_CJDNS:
1071 case NET_INTERNAL:
1072 case NET_UNROUTABLE:
1073 case NET_MAX:
1074 break;
1075 }
1076
1077 return network.ToStringAddr() + suffix;
1078 }
1079
1080 bool CSubNet::IsValid() const
1081 {
1082 return valid;
1083 }
1084
1085 bool operator==(const CSubNet& a, const CSubNet& b)
1086 {
1087 return a.valid == b.valid && a.network == b.network && !memcmp(a.netmask, b.netmask, 16);
1088 }
1089
1090 bool operator<(const CSubNet& a, const CSubNet& b)
1091 {
1092 return (a.network < b.network || (a.network == b.network && memcmp(a.netmask, b.netmask, 16) < 0));
1093 }
1094