fixes #1496 Provide NNG_ENABLE_IPV6 option (disabled by default)

CMakeLists.txt

@@ -117,6 +117,9 @@ endif ()
 
 nng_defines_if(NNG_ENABLE_STATS NNG_ENABLE_STATS)
 
+# IPv6 enable
+nng_defines_if(NNG_ENABLE_IPV6 NNG_ENABLE_IPV6)
+
 set(NNG_RESOLV_CONCURRENCY 4 CACHE STRING "Resolver (DNS) concurrency.")
 mark_as_advanced(NNG_RESOLV_CONCURRENCY)
 if (NNG_RESOLV_CONCURRENCY)

cmake/NNGOptions.cmake

@@ -106,6 +106,11 @@ if (NNG_ENABLE_HTTP)
 endif()
 mark_as_advanced(NNG_ENABLE_HTTP)
 
+# Some sites or kernels lack IPv6 support.  This override allows us
+# to prevent the use of IPv6 in environments where it isn't supported.
+option (NNG_ENABLE_IPV6 "Enable IPv6." ON)
+mark_as_advanced(NNG_ENABLE_IPV6)
+
 #
 # Transport Options.
 #

src/core/stream.c

@@ -1,5 +1,5 @@
 //
-// Copyright 2023 Staysail Systems, Inc. <[email protected]>
+// Copyright 2024 Staysail Systems, Inc. <[email protected]>
 //
 // This software is supplied under the terms of the MIT License, a
 // copy of which should be located in the distribution where this
@@ -22,8 +22,8 @@
 
 static struct {
 	const char *scheme;
-	int (*dialer_alloc)(nng_stream_dialer **, const nng_url *);
-	int (*listener_alloc)(nng_stream_listener **, const nng_url *);
+	int         (*dialer_alloc)(nng_stream_dialer **, const nng_url *);
+	int         (*listener_alloc)(nng_stream_listener **, const nng_url *);
 
 } stream_drivers[] = {
 	{
@@ -55,11 +55,13 @@ static struct {
 	    .dialer_alloc   = nni_tcp_dialer_alloc,
 	    .listener_alloc = nni_tcp_listener_alloc,
 	},
+#ifdef NNG_ENABLE_IPV6
 	{
 	    .scheme         = "tcp6",
 	    .dialer_alloc   = nni_tcp_dialer_alloc,
 	    .listener_alloc = nni_tcp_listener_alloc,
 	},
+#endif
 	{
 	    .scheme         = "tls+tcp",
 	    .dialer_alloc   = nni_tls_dialer_alloc,
@@ -70,11 +72,13 @@ static struct {
 	    .dialer_alloc   = nni_tls_dialer_alloc,
 	    .listener_alloc = nni_tls_listener_alloc,
 	},
+#ifdef NNG_ENABLE_IPV6
 	{
 	    .scheme         = "tls+tcp6",
 	    .dialer_alloc   = nni_tls_dialer_alloc,
 	    .listener_alloc = nni_tls_listener_alloc,
 	},
+#endif
 	{
 	    .scheme         = "ws",
 	    .dialer_alloc   = nni_ws_dialer_alloc,
@@ -85,11 +89,13 @@ static struct {
 	    .dialer_alloc   = nni_ws_dialer_alloc,
 	    .listener_alloc = nni_ws_listener_alloc,
 	},
+#ifdef NNG_ENABLE_IPV6
 	{
 	    .scheme         = "ws6",
 	    .dialer_alloc   = nni_ws_dialer_alloc,
 	    .listener_alloc = nni_ws_listener_alloc,
 	},
+#endif
 	{
 	    .scheme         = "wss",
 	    .dialer_alloc   = nni_ws_dialer_alloc,

src/platform/posix/CMakeLists.txt

@@ -62,6 +62,7 @@ if (NNG_PLATFORM_POSIX)
     nng_check_sym(getpeerucred ucred.h NNG_HAVE_GETPEERUCRED)
     nng_check_sym(atomic_flag_test_and_set stdatomic.h NNG_HAVE_STDATOMIC)
     nng_check_sym(socketpair sys/socket.h NNG_HAVE_SOCKETPAIR)
+    nng_check_sym(AF_INET6 netinet/in.h NNG_HAVE_INET6)
 
     nng_sources(
             posix_impl.h

src/platform/posix/posix_resolv_gai.c

@@ -33,6 +33,10 @@
 #define AI_NUMERICSERV 0
 #endif
 
+#ifndef NNG_HAVE_INET6
+#undef NNG_ENABLE_IPV6
+#endif
+
 static nni_mtx  resolv_mtx  = NNI_MTX_INITIALIZER;
 static nni_cv   resolv_cv   = NNI_CV_INITIALIZER(&resolv_mtx);
 static bool     resolv_fini = false;
@@ -182,17 +186,23 @@ resolv_task(resolv_item *item)
 
 	rv = NNG_EADDRINVAL;
 	for (probe = results; probe != NULL; probe = probe->ai_next) {
-		if ((probe->ai_addr->sa_family == AF_INET) ||
-		    (probe->ai_addr->sa_family == AF_INET6)) {
+		if (probe->ai_addr->sa_family == AF_INET) {
 			break;
 		}
+#ifdef NNG_ENABLE_IPV6
+		if (probe->ai_addr->sa_family == AF_INET6) {
+			break;
+		}
+#endif
 	}
 
 	nni_mtx_lock(&resolv_mtx);
 	if ((probe != NULL) && (item->aio != NULL)) {
-		struct sockaddr_in  *sin;
+		struct sockaddr_in *sin;
+#ifdef NNG_ENABLE_IPV6
 		struct sockaddr_in6 *sin6;
-		nng_sockaddr        *sa = item->sa;
+#endif
+		nng_sockaddr *sa = item->sa;
 
 		switch (probe->ai_addr->sa_family) {
 		case AF_INET:
@@ -202,6 +212,7 @@ resolv_task(resolv_item *item)
 			sa->s_in.sa_port   = sin->sin_port;
 			sa->s_in.sa_addr   = sin->sin_addr.s_addr;
 			break;
+#ifdef NNG_ENABLE_IPV6
 		case AF_INET6:
 			rv                  = 0;
 			sin6                = (void *) probe->ai_addr;
@@ -210,6 +221,7 @@ resolv_task(resolv_item *item)
 			sa->s_in6.sa_scope  = sin6->sin6_scope_id;
 			memcpy(sa->s_in6.sa_addr, sin6->sin6_addr.s6_addr, 16);
 			break;
+#endif
 		}
 	}
 	nni_mtx_unlock(&resolv_mtx);
@@ -238,12 +250,20 @@ nni_resolv_ip(const char *host, const char *serv, int af, bool passive,
 	case NNG_AF_INET:
 		fam = AF_INET;
 		break;
+
+#ifdef NNG_ENABLE_IPV6
 	case NNG_AF_INET6:
 		fam = AF_INET6;
 		break;
 	case NNG_AF_UNSPEC:
 		fam = AF_UNSPEC;
 		break;
+#else
+	case NNG_AF_UNSPEC:
+		fam = AF_INET;
+		break;
+#endif
+
 	default:
 		nni_aio_finish_error(aio, NNG_ENOTSUP);
 		return;
@@ -342,13 +362,17 @@ parse_ip(const char *addr, nng_sockaddr *sa, bool want_port)
 	struct addrinfo  hints;
 	struct addrinfo *results;
 	int              rv;
-	bool             v6      = false;
-	bool             wrapped = false;
 	char            *port;
 	char            *host;
 	char            *buf;
 	size_t           buf_len;
 
+#ifdef NNG_ENABLE_IPV6
+	bool  v6      = false;
+	bool  wrapped = false;
+	char *s;
+#endif
+
 	if (addr == NULL) {
 		addr = "";
 	}
@@ -359,12 +383,12 @@ parse_ip(const char *addr, nng_sockaddr *sa, bool want_port)
 	}
 	memcpy(buf, addr, buf_len);
 	host = buf;
+#ifdef NNG_ENABLE_IPV6
 	if (*host == '[') {
 		v6      = true;
 		wrapped = true;
 		host++;
 	} else {
-		char *s;
 		for (s = host; *s != '\0'; s++) {
 			if (*s == '.') {
 				break;
@@ -394,6 +418,13 @@ parse_ip(const char *addr, nng_sockaddr *sa, bool want_port)
 		rv = NNG_EADDRINVAL;
 		goto done;
 	}
+#else  // NNG_ENABLE_IPV6
+	for (port = host; *port != '\0'; port++) {
+		if (*port == ':') {
+			break;
+		}
+	}
+#endif // NNG_ENABLE_IPV6
 
 	if ((!want_port) && (*port != '\0')) {
 		rv = NNG_EADDRINVAL;
@@ -408,9 +439,13 @@ parse_ip(const char *addr, nng_sockaddr *sa, bool want_port)
 
 	memset(&hints, 0, sizeof(hints));
 	hints.ai_flags = AI_NUMERICSERV | AI_NUMERICHOST | AI_PASSIVE;
+#ifdef NNG_ENABLE_IPV6
 	if (v6) {
 		hints.ai_family = AF_INET6;
 	}
+#else
+	hints.ai_family = AF_INET;
+#endif
 #ifdef AI_ADDRCONFIG
 	hints.ai_flags |= AI_ADDRCONFIG;
 #endif

src/platform/posix/posix_sockaddr.c

@@ -1,5 +1,5 @@
 //
-// Copyright 2020 Staysail Systems, Inc. <[email protected]>
+// Copyright 2024 Staysail Systems, Inc. <[email protected]>
 // Copyright 2018 Capitar IT Group BV <[email protected]>
 //
 // This software is supplied under the terms of the MIT License, a
@@ -22,17 +22,23 @@
 #include <sys/types.h>
 #include <sys/un.h>
 
+#ifndef NNG_HAVE_INET6
+#undef NNG_ENABLE_IPV6
+#endif
+
 size_t
 nni_posix_nn2sockaddr(void *sa, const nni_sockaddr *na)
 {
-	struct sockaddr_in *         sin;
-	struct sockaddr_in6 *        sin6;
-	struct sockaddr_un *         spath;
-	const nng_sockaddr_in *      nsin;
-	const nng_sockaddr_in6 *     nsin6;
-	const nng_sockaddr_path *    nspath;
+	struct sockaddr_in          *sin;
+	struct sockaddr_un          *spath;
+	const nng_sockaddr_in       *nsin;
+	const nng_sockaddr_path     *nspath;
 	const nng_sockaddr_abstract *nsabs;
 	size_t                       sz;
+#ifdef NNG_ENABLE_IPV6
+	struct sockaddr_in6    *sin6;
+	const nng_sockaddr_in6 *nsin6;
+#endif
 
 	if ((sa == NULL) || (na == NULL)) {
 		return (0);
@@ -47,6 +53,7 @@
 		sin->sin_addr.s_addr = nsin->sa_addr;
 		return (sizeof(*sin));
 
+#ifdef NNG_ENABLE_IPV6
 	case NNG_AF_INET6:
 		sin6  = (void *) sa;
 		nsin6 = &na->s_in6;
@@ -59,6 +66,7 @@
 		sin6->sin6_scope_id = nsin6->sa_scope;
 		memcpy(sin6->sin6_addr.s6_addr, nsin6->sa_addr, 16);
 		return (sizeof(*sin6));
+#endif
 
 	case NNG_AF_IPC:
 		spath  = (void *) sa;
@@ -75,18 +83,18 @@
 	case NNG_AF_ABSTRACT:
 		spath = (void *) sa;
 		nsabs = &na->s_abstract;
-		if (nsabs->sa_len >= sizeof (spath->sun_path)) {
+		if (nsabs->sa_len >= sizeof(spath->sun_path)) {
 			return (0);
 		}
 		memset(spath, 0, sizeof(*spath));
-		spath->sun_family = PF_UNIX;
+		spath->sun_family  = PF_UNIX;
 		spath->sun_path[0] = '\0'; // abstract starts with nul
 
 		// We support auto-bind with an empty string.  There is
 		// a subtle caveat here, which is that we cannot bind to
 		// the *empty* name.
 		if (nsabs->sa_len == 0) {
-			return (sizeof (sa_family_t)); // auto bind
+			return (sizeof(sa_family_t)); // auto bind
 		} else {
 			memcpy(&spath->sun_path[1], nsabs->sa_name,
 			    nsabs->sa_len);
@@ -99,13 +107,15 @@
 int
 nni_posix_sockaddr2nn(nni_sockaddr *na, const void *sa, size_t sz)
 {
-	const struct sockaddr_in * sin;
+	const struct sockaddr_in *sin;
+	const struct sockaddr_un *spath;
+	nng_sockaddr_in          *nsin;
+	nng_sockaddr_path        *nspath;
+	nng_sockaddr_abstract    *nsabs;
+#ifdef NNG_ENABLE_IPV6
 	const struct sockaddr_in6 *sin6;
-	const struct sockaddr_un * spath;
-	nng_sockaddr_in *          nsin;
-	nng_sockaddr_in6 *         nsin6;
-	nng_sockaddr_path *        nspath;
-	nng_sockaddr_abstract *    nsabs;
+	nng_sockaddr_in6          *nsin6;
+#endif
 
 	if ((na == NULL) || (sa == NULL)) {
 		return (-1);
@@ -121,6 +131,8 @@
 		nsin->sa_port   = sin->sin_port;
 		nsin->sa_addr   = sin->sin_addr.s_addr;
 		break;
+
+#ifdef NNG_ENABLE_IPV6
 	case AF_INET6:
 		if (sz < sizeof(*sin6)) {
 			return (-1);
@@ -132,6 +144,8 @@
 		nsin6->sa_scope  = sin6->sin6_scope_id;
 		memcpy(nsin6->sa_addr, sin6->sin6_addr.s6_addr, 16);
 		break;
+#endif
+
 	case AF_UNIX:
 		// AF_UNIX can be NNG_AF_IPC, or NNG_AF_ABSTRACT.
 		spath = (void *) sa;
@@ -153,7 +167,7 @@
 			nsabs->sa_len    = sz - 1;
 			memcpy(nsabs->sa_name, &spath->sun_path[1], sz - 1);
 		} else {
-                        nspath            = &na->s_ipc;
+			nspath            = &na->s_ipc;
 			nspath->sa_family = NNG_AF_IPC;
 			nni_strlcpy(nspath->sa_path, spath->sun_path,
 			    sizeof(nspath->sa_path));