summaryrefslogtreecommitdiffstats
path: root/lib/isc/net.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/isc/net.c')
-rw-r--r--lib/isc/net.c497
1 files changed, 497 insertions, 0 deletions
diff --git a/lib/isc/net.c b/lib/isc/net.c
new file mode 100644
index 0000000..e32a543
--- /dev/null
+++ b/lib/isc/net.c
@@ -0,0 +1,497 @@
+/*
+ * 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 <stdbool.h>
+#include <sys/types.h>
+
+#if defined(HAVE_SYS_SYSCTL_H) && !defined(__linux__)
+#if defined(HAVE_SYS_PARAM_H)
+#include <sys/param.h>
+#endif /* if defined(HAVE_SYS_PARAM_H) */
+#include <sys/sysctl.h>
+#endif /* if defined(HAVE_SYS_SYSCTL_H) && !defined(__linux__) */
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/uio.h>
+#include <unistd.h>
+
+#include <isc/log.h>
+#include <isc/net.h>
+#include <isc/netdb.h>
+#include <isc/once.h>
+#include <isc/strerr.h>
+#include <isc/string.h>
+#include <isc/util.h>
+
+#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;
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-03 15:41:18 +0000