/* * Copyright (C) 1996-2023 The Squid Software Foundation and contributors * * Squid software is distributed under GPLv2+ license and includes * contributions from numerous individuals and organizations. * Please see the COPYING and CONTRIBUTORS files for details. */ /* DEBUG: section 21 Misc Functions */ #include "squid.h" #include "debug/Messages.h" #include "ip/Address.h" #include "ip/tools.h" #if HAVE_UNISTD_H #include #endif #if HAVE_SYS_SOCKET_H #include #endif #if HAVE_NETINET_IN_H #include #endif #if HAVE_NETINET_IN6_H #include #endif int Ip::EnableIpv6 = IPV6_OFF; void Ip::ProbeTransport() { // check for usable IPv6 sockets int s = socket(PF_INET6, SOCK_STREAM, 0); if (s < 0) { debugs(3, 2, "IPv6 not supported on this machine. Auto-Disabled."); EnableIpv6 = IPV6_OFF; return; } // Test for v4-mapping capability // (AKA. the operating system supports RFC 3493 section 5.3) #if defined(IPV6_V6ONLY) int tos = 0; if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, (char *) &tos, sizeof(int)) == 0) { debugs(3, 2, "Detected IPv6 hybrid or v4-mapping stack..."); EnableIpv6 |= IPV6_SPECIAL_V4MAPPING; } else { debugs(3, 2, "Detected split IPv4 and IPv6 stacks ..."); EnableIpv6 |= IPV6_SPECIAL_SPLITSTACK; } #else // compliance here means they at least supply the option for compilers building code // even if possibly to return hard-coded -1 on use. debugs(3, 2, "Missing RFC 3493 compliance - attempting split IPv4 and IPv6 stacks ..."); EnableIpv6 |= IPV6_SPECIAL_SPLITSTACK; #endif // Test for IPv6 loopback/localhost address binding Ip::Address ip; ip.setLocalhost(); if (ip.isIPv6()) { // paranoid; always succeeds if we got this far struct sockaddr_in6 sin; ip.getSockAddr(sin); if (bind(s, reinterpret_cast(&sin), sizeof(sin)) != 0) { debugs(3, Critical(66), "WARNING: BCP 177 violation. Detected non-functional IPv6 loopback."); EnableIpv6 = IPV6_OFF; } else { debugs(3, 2, "Detected functional IPv6 loopback ..."); } } close(s); #if USE_IPV6 debugs(3, 2, "IPv6 transport " << (EnableIpv6?"Enabled":"Disabled")); #else debugs(3, 2, "IPv6 transport " << (EnableIpv6?"Available":"Disabled")); if (EnableIpv6 != IPV6_OFF) { debugs(3, Critical(67), "WARNING: BCP 177 violation. IPv6 transport forced OFF by build parameters."); EnableIpv6 = IPV6_OFF; } #endif }