/* $NetBSD: net.c,v 1.2.4.2 2024/02/29 12:35:01 martin Exp $ */ /* * Copyright (C) Internet Systems Consortium, Inc. ("ISC") * * SPDX-License-Identifier: MPL-2.0 * * This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, you can obtain one at https://mozilla.org/MPL/2.0/. * * See the COPYRIGHT file distributed with this work for additional * information regarding copyright ownership. */ #include #include #if defined(HAVE_SYS_SYSCTL_H) && !defined(__linux__) #if defined(HAVE_SYS_PARAM_H) #include #endif /* if defined(HAVE_SYS_PARAM_H) */ #include #endif /* if defined(HAVE_SYS_SYSCTL_H) && !defined(__linux__) */ #include #include #include #include #include #include #include #include #include #include #include #ifndef socklen_t #define socklen_t unsigned int #endif /* ifndef socklen_t */ /*% * Definitions about UDP port range specification. This is a total mess of * portability variants: some use sysctl (but the sysctl names vary), some use * system-specific interfaces, some have the same interface for IPv4 and IPv6, * some separate them, etc... */ /*% * The last resort defaults: use all non well known port space */ #ifndef ISC_NET_PORTRANGELOW #define ISC_NET_PORTRANGELOW 1024 #endif /* ISC_NET_PORTRANGELOW */ #ifndef ISC_NET_PORTRANGEHIGH #define ISC_NET_PORTRANGEHIGH 65535 #endif /* ISC_NET_PORTRANGEHIGH */ #ifdef HAVE_SYSCTLBYNAME /*% * sysctl variants */ #if defined(__FreeBSD__) || defined(__APPLE__) || defined(__DragonFly__) #define USE_SYSCTL_PORTRANGE #define SYSCTL_V4PORTRANGE_LOW "net.inet.ip.portrange.hifirst" #define SYSCTL_V4PORTRANGE_HIGH "net.inet.ip.portrange.hilast" #define SYSCTL_V6PORTRANGE_LOW "net.inet.ip.portrange.hifirst" #define SYSCTL_V6PORTRANGE_HIGH "net.inet.ip.portrange.hilast" #endif /* if defined(__FreeBSD__) || defined(__APPLE__) || \ * defined(__DragonFly__) */ #ifdef __NetBSD__ #define USE_SYSCTL_PORTRANGE #define SYSCTL_V4PORTRANGE_LOW "net.inet.ip.anonportmin" #define SYSCTL_V4PORTRANGE_HIGH "net.inet.ip.anonportmax" #define SYSCTL_V6PORTRANGE_LOW "net.inet6.ip6.anonportmin" #define SYSCTL_V6PORTRANGE_HIGH "net.inet6.ip6.anonportmax" #endif /* ifdef __NetBSD__ */ #else /* !HAVE_SYSCTLBYNAME */ #ifdef __OpenBSD__ #define USE_SYSCTL_PORTRANGE #define SYSCTL_V4PORTRANGE_LOW \ { \ CTL_NET, PF_INET, IPPROTO_IP, IPCTL_IPPORT_HIFIRSTAUTO \ } #define SYSCTL_V4PORTRANGE_HIGH \ { \ CTL_NET, PF_INET, IPPROTO_IP, IPCTL_IPPORT_HILASTAUTO \ } /* Same for IPv6 */ #define SYSCTL_V6PORTRANGE_LOW SYSCTL_V4PORTRANGE_LOW #define SYSCTL_V6PORTRANGE_HIGH SYSCTL_V4PORTRANGE_HIGH #endif /* ifdef __OpenBSD__ */ #endif /* HAVE_SYSCTLBYNAME */ static isc_once_t once_ipv6only = ISC_ONCE_INIT; #ifdef __notyet__ static isc_once_t once_ipv6pktinfo = ISC_ONCE_INIT; #endif /* ifdef __notyet__ */ #ifndef ISC_CMSG_IP_TOS #ifdef __APPLE__ #define ISC_CMSG_IP_TOS 0 /* As of 10.8.2. */ #else /* ! __APPLE__ */ #define ISC_CMSG_IP_TOS 1 #endif /* ! __APPLE__ */ #endif /* ! ISC_CMSG_IP_TOS */ static isc_once_t once = ISC_ONCE_INIT; static isc_result_t ipv4_result = ISC_R_NOTFOUND; static isc_result_t ipv6_result = ISC_R_NOTFOUND; static isc_result_t unix_result = ISC_R_NOTFOUND; static isc_result_t ipv6only_result = ISC_R_NOTFOUND; static isc_result_t ipv6pktinfo_result = ISC_R_NOTFOUND; static isc_result_t try_proto(int domain) { int s; isc_result_t result = ISC_R_SUCCESS; s = socket(domain, SOCK_STREAM, 0); if (s == -1) { switch (errno) { #ifdef EAFNOSUPPORT case EAFNOSUPPORT: #endif /* ifdef EAFNOSUPPORT */ #ifdef EPFNOSUPPORT case EPFNOSUPPORT: #endif /* ifdef EPFNOSUPPORT */ #ifdef EPROTONOSUPPORT case EPROTONOSUPPORT: #endif /* ifdef EPROTONOSUPPORT */ #ifdef EINVAL case EINVAL: #endif /* ifdef EINVAL */ return (ISC_R_NOTFOUND); default: UNEXPECTED_SYSERROR(errno, "socket()"); return (ISC_R_UNEXPECTED); } } if (domain == PF_INET6) { struct sockaddr_in6 sin6; unsigned int len; /* * Check to see if IPv6 is broken, as is common on Linux. */ len = sizeof(sin6); if (getsockname(s, (struct sockaddr *)&sin6, (void *)&len) < 0) { isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL, ISC_LOGMODULE_SOCKET, ISC_LOG_ERROR, "retrieving the address of an IPv6 " "socket from the kernel failed."); isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL, ISC_LOGMODULE_SOCKET, ISC_LOG_ERROR, "IPv6 is not supported."); result = ISC_R_NOTFOUND; } else { if (len == sizeof(struct sockaddr_in6)) { result = ISC_R_SUCCESS; } else { isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL, ISC_LOGMODULE_SOCKET, ISC_LOG_ERROR, "IPv6 structures in kernel and " "user space do not match."); isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL, ISC_LOGMODULE_SOCKET, ISC_LOG_ERROR, "IPv6 is not supported."); result = ISC_R_NOTFOUND; } } } (void)close(s); return (result); } static void initialize_action(void) { ipv4_result = try_proto(PF_INET); ipv6_result = try_proto(PF_INET6); unix_result = try_proto(PF_UNIX); } static void initialize(void) { RUNTIME_CHECK(isc_once_do(&once, initialize_action) == ISC_R_SUCCESS); } isc_result_t isc_net_probeipv4(void) { initialize(); return (ipv4_result); } isc_result_t isc_net_probeipv6(void) { initialize(); return (ipv6_result); } isc_result_t isc_net_probeunix(void) { initialize(); return (unix_result); } static void try_ipv6only(void) { #ifdef IPV6_V6ONLY int s, on; #endif /* ifdef IPV6_V6ONLY */ isc_result_t result; result = isc_net_probeipv6(); if (result != ISC_R_SUCCESS) { ipv6only_result = result; return; } #ifndef IPV6_V6ONLY ipv6only_result = ISC_R_NOTFOUND; return; #else /* ifndef IPV6_V6ONLY */ /* check for TCP sockets */ s = socket(PF_INET6, SOCK_STREAM, 0); if (s == -1) { UNEXPECTED_SYSERROR(errno, "socket()"); ipv6only_result = ISC_R_UNEXPECTED; return; } on = 1; if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) < 0) { ipv6only_result = ISC_R_NOTFOUND; goto close; } close(s); /* check for UDP sockets */ s = socket(PF_INET6, SOCK_DGRAM, 0); if (s == -1) { UNEXPECTED_SYSERROR(errno, "socket()"); ipv6only_result = ISC_R_UNEXPECTED; return; } on = 1; if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) < 0) { ipv6only_result = ISC_R_NOTFOUND; goto close; } ipv6only_result = ISC_R_SUCCESS; close: close(s); return; #endif /* IPV6_V6ONLY */ } static void initialize_ipv6only(void) { RUNTIME_CHECK(isc_once_do(&once_ipv6only, try_ipv6only) == ISC_R_SUCCESS); } #ifdef __notyet__ static void try_ipv6pktinfo(void) { int s, on; isc_result_t result; int optname; result = isc_net_probeipv6(); if (result != ISC_R_SUCCESS) { ipv6pktinfo_result = result; return; } /* we only use this for UDP sockets */ s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_UDP); if (s == -1) { UNEXPECTED_SYSERROR(errno, "socket()"); ipv6pktinfo_result = ISC_R_UNEXPECTED; return; } #ifdef IPV6_RECVPKTINFO optname = IPV6_RECVPKTINFO; #else /* ifdef IPV6_RECVPKTINFO */ optname = IPV6_PKTINFO; #endif /* ifdef IPV6_RECVPKTINFO */ on = 1; if (setsockopt(s, IPPROTO_IPV6, optname, &on, sizeof(on)) < 0) { ipv6pktinfo_result = ISC_R_NOTFOUND; goto close; } ipv6pktinfo_result = ISC_R_SUCCESS; close: close(s); return; } static void initialize_ipv6pktinfo(void) { RUNTIME_CHECK(isc_once_do(&once_ipv6pktinfo, try_ipv6pktinfo) == ISC_R_SUCCESS); } #endif /* ifdef __notyet__ */ isc_result_t isc_net_probe_ipv6only(void) { initialize_ipv6only(); return (ipv6only_result); } isc_result_t isc_net_probe_ipv6pktinfo(void) { /* * XXXWPK if pktinfo were supported then we could listen on :: for ipv6 and get * the information about the destination address from pktinfo structure passed * in recvmsg but this method is not portable and libuv doesn't support it - so * we need to listen on all interfaces. * We should verify that this doesn't impact performance (we already do it for * ipv4) and either remove all the ipv6pktinfo detection code from above * or think of fixing libuv. */ #ifdef __notyet__ initialize_ipv6pktinfo(); #endif /* ifdef __notyet__ */ return (ipv6pktinfo_result); } #if defined(USE_SYSCTL_PORTRANGE) #if defined(HAVE_SYSCTLBYNAME) static isc_result_t getudpportrange_sysctl(int af, in_port_t *low, in_port_t *high) { int port_low, port_high; size_t portlen; const char *sysctlname_lowport, *sysctlname_hiport; if (af == AF_INET) { sysctlname_lowport = SYSCTL_V4PORTRANGE_LOW; sysctlname_hiport = SYSCTL_V4PORTRANGE_HIGH; } else { sysctlname_lowport = SYSCTL_V6PORTRANGE_LOW; sysctlname_hiport = SYSCTL_V6PORTRANGE_HIGH; } portlen = sizeof(port_low); if (sysctlbyname(sysctlname_lowport, &port_low, &portlen, NULL, 0) < 0) { return (ISC_R_FAILURE); } portlen = sizeof(port_high); if (sysctlbyname(sysctlname_hiport, &port_high, &portlen, NULL, 0) < 0) { return (ISC_R_FAILURE); } if ((port_low & ~0xffff) != 0 || (port_high & ~0xffff) != 0) { return (ISC_R_RANGE); } *low = (in_port_t)port_low; *high = (in_port_t)port_high; return (ISC_R_SUCCESS); } #else /* !HAVE_SYSCTLBYNAME */ static isc_result_t getudpportrange_sysctl(int af, in_port_t *low, in_port_t *high) { int mib_lo4[4] = SYSCTL_V4PORTRANGE_LOW; int mib_hi4[4] = SYSCTL_V4PORTRANGE_HIGH; int mib_lo6[4] = SYSCTL_V6PORTRANGE_LOW; int mib_hi6[4] = SYSCTL_V6PORTRANGE_HIGH; int *mib_lo, *mib_hi, miblen; int port_low, port_high; size_t portlen; if (af == AF_INET) { mib_lo = mib_lo4; mib_hi = mib_hi4; miblen = sizeof(mib_lo4) / sizeof(mib_lo4[0]); } else { mib_lo = mib_lo6; mib_hi = mib_hi6; miblen = sizeof(mib_lo6) / sizeof(mib_lo6[0]); } portlen = sizeof(port_low); if (sysctl(mib_lo, miblen, &port_low, &portlen, NULL, 0) < 0) { return (ISC_R_FAILURE); } portlen = sizeof(port_high); if (sysctl(mib_hi, miblen, &port_high, &portlen, NULL, 0) < 0) { return (ISC_R_FAILURE); } if ((port_low & ~0xffff) != 0 || (port_high & ~0xffff) != 0) { return (ISC_R_RANGE); } *low = (in_port_t)port_low; *high = (in_port_t)port_high; return (ISC_R_SUCCESS); } #endif /* HAVE_SYSCTLBYNAME */ #endif /* USE_SYSCTL_PORTRANGE */ isc_result_t isc_net_getudpportrange(int af, in_port_t *low, in_port_t *high) { int result = ISC_R_FAILURE; #if !defined(USE_SYSCTL_PORTRANGE) && defined(__linux) FILE *fp; #endif /* if !defined(USE_SYSCTL_PORTRANGE) && defined(__linux) */ REQUIRE(low != NULL && high != NULL); #if defined(USE_SYSCTL_PORTRANGE) result = getudpportrange_sysctl(af, low, high); #elif defined(__linux) UNUSED(af); /* * Linux local ports are address family agnostic. */ fp = fopen("/proc/sys/net/ipv4/ip_local_port_range", "r"); if (fp != NULL) { int n; unsigned int l, h; n = fscanf(fp, "%u %u", &l, &h); if (n == 2 && (l & ~0xffff) == 0 && (h & ~0xffff) == 0) { *low = l; *high = h; result = ISC_R_SUCCESS; } fclose(fp); } #else /* if defined(USE_SYSCTL_PORTRANGE) */ UNUSED(af); #endif /* if defined(USE_SYSCTL_PORTRANGE) */ if (result != ISC_R_SUCCESS) { *low = ISC_NET_PORTRANGELOW; *high = ISC_NET_PORTRANGEHIGH; } return (ISC_R_SUCCESS); /* we currently never fail in this function */ } void isc_net_disableipv4(void) { initialize(); if (ipv4_result == ISC_R_SUCCESS) { ipv4_result = ISC_R_DISABLED; } } void isc_net_disableipv6(void) { initialize(); if (ipv6_result == ISC_R_SUCCESS) { ipv6_result = ISC_R_DISABLED; } } void isc_net_enableipv4(void) { initialize(); if (ipv4_result == ISC_R_DISABLED) { ipv4_result = ISC_R_SUCCESS; } } void isc_net_enableipv6(void) { initialize(); if (ipv6_result == ISC_R_DISABLED) { ipv6_result = ISC_R_SUCCESS; } }