From dc7fb26921993fd710b81d828afe7afee95eb31d Mon Sep 17 00:00:00 2001 From: sfan5 Date: Mon, 1 Jan 2024 15:35:46 +0100 Subject: [PATCH] Extend capabilities of Address class --- src/client/game.cpp | 3 +- src/network/address.cpp | 78 +++++++++++++++++------------------ src/network/address.h | 27 ++++++++---- src/unittest/test_address.cpp | 52 +++++++++++++++++++++++ 4 files changed, 111 insertions(+), 49 deletions(-) diff --git a/src/client/game.cpp b/src/client/game.cpp index 40fea4307..518718223 100644 --- a/src/client/game.cpp +++ b/src/client/game.cpp @@ -1621,7 +1621,8 @@ bool Game::connectToServer(const GameStartData &start_data, try { connect_address.Resolve(start_data.address.c_str()); - if (connect_address.isZero()) { // i.e. INADDR_ANY, IN6ADDR_ANY + if (connect_address.isAny()) { + // replace with localhost IP if (connect_address.isIPv6()) { IPv6AddressBytes addr_bytes; addr_bytes.bytes[15] = 1; diff --git a/src/network/address.cpp b/src/network/address.cpp index df1e3b852..846008078 100644 --- a/src/network/address.cpp +++ b/src/network/address.cpp @@ -84,7 +84,7 @@ Address::Address(const IPv6AddressBytes *ipv6_bytes, u16 port) } // Equality (address family, IP and port must be equal) -bool Address::operator==(const Address &other) +bool Address::operator==(const Address &other) const { if (other.m_addr_family != m_addr_family || other.m_port != m_port) return false; @@ -101,44 +101,60 @@ bool Address::operator==(const Address &other) return false; } -void Address::Resolve(const char *name) +void Address::Resolve(const char *name, Address *fallback) { if (!name || name[0] == 0) { if (m_addr_family == AF_INET) setAddress(static_cast(0)); else if (m_addr_family == AF_INET6) setAddress(static_cast(nullptr)); + if (fallback) + *fallback = Address(); return; } - struct addrinfo *resolved, hints; + const auto ©_from_ai = [] (const struct addrinfo *ai, Address *to) { + if (ai->ai_family == AF_INET) { + struct sockaddr_in *t = (struct sockaddr_in *)ai->ai_addr; + to->m_addr_family = AF_INET; + to->m_address.ipv4 = t->sin_addr; + } else if (ai->ai_family == AF_INET6) { + struct sockaddr_in6 *t = (struct sockaddr_in6 *)ai->ai_addr; + to->m_addr_family = AF_INET6; + to->m_address.ipv6 = t->sin6_addr; + } else { + to->m_addr_family = 0; + } + }; + + struct addrinfo hints; memset(&hints, 0, sizeof(hints)); - // Setup hints + // set a type, so every unique address is only returned once + hints.ai_socktype = SOCK_DGRAM; if (g_settings->getBool("enable_ipv6")) { // AF_UNSPEC allows both IPv6 and IPv4 addresses to be returned hints.ai_family = AF_UNSPEC; } else { hints.ai_family = AF_INET; } + hints.ai_flags = AI_ADDRCONFIG; // Do getaddrinfo() - int e = getaddrinfo(name, NULL, &hints, &resolved); + struct addrinfo *resolved = nullptr; + int e = getaddrinfo(name, nullptr, &hints, &resolved); if (e != 0) throw ResolveError(gai_strerror(e)); + assert(resolved); // Copy data - if (resolved->ai_family == AF_INET) { - struct sockaddr_in *t = (struct sockaddr_in *)resolved->ai_addr; - m_addr_family = AF_INET; - m_address.ipv4 = t->sin_addr; - } else if (resolved->ai_family == AF_INET6) { - struct sockaddr_in6 *t = (struct sockaddr_in6 *)resolved->ai_addr; - m_addr_family = AF_INET6; - m_address.ipv6 = t->sin6_addr; - } else { - m_addr_family = 0; + copy_from_ai(resolved, this); + if (fallback) { + *fallback = Address(); + if (resolved->ai_next) + copy_from_ai(resolved->ai_next, fallback); } + freeaddrinfo(resolved); } @@ -151,28 +167,11 @@ std::string Address::serializeString() const return str; } -struct in_addr Address::getAddress() const -{ - return m_address.ipv4; -} - -struct in6_addr Address::getAddress6() const -{ - return m_address.ipv6; -} - -u16 Address::getPort() const -{ - return m_port; -} - -bool Address::isZero() const +bool Address::isAny() const { if (m_addr_family == AF_INET) { return m_address.ipv4.s_addr == 0; - } - - if (m_addr_family == AF_INET6) { + } else if (m_addr_family == AF_INET6) { static const char zero[16] = {0}; return memcmp(m_address.ipv6.s6_addr, zero, 16) == 0; } @@ -218,18 +217,19 @@ void Address::print(std::ostream& s) const bool Address::isLocalhost() const { - if (isIPv6()) { + if (m_addr_family == AF_INET6) { static const u8 localhost_bytes[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}; static const u8 mapped_ipv4_localhost[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff, 0x7f, 0, 0, 0}; - auto addr = m_address.ipv6.s6_addr; + auto *addr = m_address.ipv6.s6_addr; return memcmp(addr, localhost_bytes, 16) == 0 || memcmp(addr, mapped_ipv4_localhost, 13) == 0; + } else if (m_addr_family == AF_INET) { + auto addr = ntohl(m_address.ipv4.s_addr); + return (addr >> 24) == 0x7f; } - - auto addr = ntohl(m_address.ipv4.s_addr); - return (addr >> 24) == 0x7f; + return false; } diff --git a/src/network/address.h b/src/network/address.h index 03528c53b..2fbf419a7 100644 --- a/src/network/address.h +++ b/src/network/address.h @@ -47,21 +47,29 @@ public: Address(u8 a, u8 b, u8 c, u8 d, u16 port); Address(const IPv6AddressBytes *ipv6_bytes, u16 port); - bool operator==(const Address &address); - bool operator!=(const Address &address) { return !(*this == address); } + bool operator==(const Address &address) const; + bool operator!=(const Address &address) const { return !(*this == address); } - struct in_addr getAddress() const; - struct in6_addr getAddress6() const; - u16 getPort() const; int getFamily() const { return m_addr_family; } + bool isValid() const { return m_addr_family != 0; } bool isIPv6() const { return m_addr_family == AF_INET6; } - bool isZero() const; + struct in_addr getAddress() const { return m_address.ipv4; } + struct in6_addr getAddress6() const { return m_address.ipv6; } + u16 getPort() const { return m_port; } + void print(std::ostream &s) const; std::string serializeString() const; + + // Is this an address that binds to all interfaces (like INADDR_ANY)? + bool isAny() const; + // Is this an address referring to the local host? bool isLocalhost() const; - // Resolve() may throw ResolveError (address is unchanged in this case) - void Resolve(const char *name); + // `name`: hostname or numeric IP + // `fallback`: fallback IP to try gets written here + // any empty name resets the IP to the "any address" + // may throw ResolveError (address is unchanged in this case) + void Resolve(const char *name, Address *fallback = nullptr); void setAddress(u32 address); void setAddress(u8 a, u8 b, u8 c, u8 d); @@ -75,5 +83,6 @@ private: struct in_addr ipv4; struct in6_addr ipv6; } m_address; - u16 m_port = 0; // Port is separate from sockaddr structures + // port is separate from in_addr structures + u16 m_port = 0; }; diff --git a/src/unittest/test_address.cpp b/src/unittest/test_address.cpp index f46135577..dd77d0264 100644 --- a/src/unittest/test_address.cpp +++ b/src/unittest/test_address.cpp @@ -32,14 +32,36 @@ public: void runTests(IGameDef *gamedef); + void testBasic(); void testIsLocalhost(); + void testResolve(); }; static TestAddress g_test_instance; void TestAddress::runTests(IGameDef *gamedef) { + TEST(testBasic); TEST(testIsLocalhost); + TEST(testResolve); +} + +void TestAddress::testBasic() +{ + Address tmp; + + UASSERT(!tmp.isValid()); + UASSERTEQ(int, tmp.getFamily(), 0); + + tmp = Address(static_cast(0), 0); + UASSERT(tmp.isValid()); + UASSERTEQ(int, tmp.getFamily(), AF_INET); + UASSERT(tmp.isAny()); + + tmp = Address(static_cast(nullptr), 0); + UASSERT(tmp.isValid()); + UASSERTEQ(int, tmp.getFamily(), AF_INET6); + UASSERT(tmp.isAny()); } void TestAddress::testIsLocalhost() @@ -65,3 +87,33 @@ void TestAddress::testIsLocalhost() memcpy(ipv6Bytes->bytes, &ipv6RawAddr[0], 16); UASSERT(!Address(ipv6Bytes.get(), 0).isLocalhost()) } + +void TestAddress::testResolve() +{ + // Empty test + { + Address tmp(1, 2, 3, 4, 5); + tmp.Resolve(""); + + UASSERT(tmp.isValid()); + UASSERT(tmp.isAny()); + } + + // Localhost test + Address result, fallback; + result.Resolve("localhost", &fallback); + + UASSERT(result.isValid()); + UASSERT(result.isLocalhost()); + + if (fallback.isValid()) { + UASSERT(fallback.isLocalhost()); + + // the result should be ::1 and 127.0.0.1 so the fallback addr should be + // of a different family + UASSERTCMP(int, !=, result.getFamily(), fallback.getFamily()); + } else if (g_settings->getBool("enable_ipv6")) { + warningstream << "Couldn't verify Address::Resolve fallback (no IPv6?)" + << std::endl; + } +}