telnetd: move generic stuff into libbb. It will make it easy

to make other server applets IPv6-aware too.

1 files changed, 152 insertions, 0 deletions

diff --git a/libbb/xconnect.c b/libbb/xconnect.c
index 21ec2761a..cf1f9d59a 100644
--- a/libbb/xconnect.c
+++ b/libbb/xconnect.c
@@ -66,3 +66,155 @@ int xconnect_tcp_v4(struct sockaddr_in *s_addr)
 	xconnect(s, (struct sockaddr*) s_addr, sizeof(*s_addr));
 	return s;
 }
+
+int dotted2sockaddr(const char *dotted, struct sockaddr* sp, int socklen)
+{
+	union {
+		struct in_addr a4;
+#if ENABLE_FEATURE_IPV6
+		struct in6_addr a6;
+#endif
+	} a;
+
+	/* TODO maybe: port spec? like n.n.n.n:nn */
+
+#if ENABLE_FEATURE_IPV6
+	if (socklen >= sizeof(struct sockaddr_in6)
+	 && inet_pton(AF_INET6, dotted, &a.a6) > 0
+	) {
+		((struct sockaddr_in6*)sp)->sin6_family = AF_INET6;
+		((struct sockaddr_in6*)sp)->sin6_addr = a.a6;
+		/* ((struct sockaddr_in6*)sp)->sin6_port = */
+		return 0; /* success */
+	}
+#endif
+	if (socklen >= sizeof(struct sockaddr_in)
+	 && inet_pton(AF_INET, dotted, &a.a4) > 0
+	) {
+		((struct sockaddr_in*)sp)->sin_family = AF_INET;
+		((struct sockaddr_in*)sp)->sin_addr = a.a4;
+		/* ((struct sockaddr_in*)sp)->sin_port = */
+		return 0; /* success */
+	}
+	return 1;
+}
+
+int xsocket_stream_ip4or6(sa_family_t *fp)
+{
+	int fd;
+#if ENABLE_FEATURE_IPV6
+	fd = socket(AF_INET6, SOCK_STREAM, 0);
+	if (fp) *fp = AF_INET6;
+	if (fd < 0)
+#endif
+	{
+		fd = xsocket(AF_INET, SOCK_STREAM, 0);
+		if (fp) *fp = AF_INET;
+	}
+	return fd;
+}
+
+int create_and_bind_socket_ip4or6(const char *hostaddr, int port)
+{
+	static const int on = 1;
+	int fd;
+	sockaddr_inet sa;
+
+	memset(&sa, 0, sizeof(sa));
+	if (hostaddr && dotted2sockaddr(hostaddr, &sa.sa, sizeof(sa)))
+		bb_show_usage();
+
+	if (!sa.sa.sa_family)
+		fd = xsocket_stream_ip4or6(&sa.sa.sa_family);
+	else /* user specified bind addr dictates family */
+		fd = xsocket(sa.sa.sa_family, SOCK_STREAM, 0);
+	setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
+
+	/* if (port >= 0) { */
+#if ENABLE_FEATURE_IPV6
+		if (sa.sa.sa_family == AF_INET6 /* && !sa.sin6.sin6_port */)
+			sa.sin6.sin6_port = htons(port);
+#endif
+		if (sa.sa.sa_family == AF_INET /* && !sa.sin.sin_port */)
+			sa.sin.sin_port = htons(port);
+	/* } */
+
+	xbind(fd, &sa.sa, sizeof(sa));
+	return fd;
+}
+
+int dotted2sockaddr(const char *dotted, struct sockaddr* sp, int socklen)
+{
+	union {
+		struct in_addr a4;
+#if ENABLE_FEATURE_IPV6
+		struct in6_addr a6;
+#endif
+	} a;
+
+	/* TODO maybe: port spec? like n.n.n.n:nn */
+
+#if ENABLE_FEATURE_IPV6
+	if (socklen >= sizeof(struct sockaddr_in6)
+	 && inet_pton(AF_INET6, dotted, &a.a6) > 0
+	) {
+		((struct sockaddr_in6*)sp)->sin6_family = AF_INET6;
+		((struct sockaddr_in6*)sp)->sin6_addr = a.a6;
+		/* ((struct sockaddr_in6*)sp)->sin6_port = */
+		return 0; /* success */
+	}
+#endif
+	if (socklen >= sizeof(struct sockaddr_in)
+	 && inet_pton(AF_INET, dotted, &a.a4) > 0
+	) {
+		((struct sockaddr_in*)sp)->sin_family = AF_INET;
+		((struct sockaddr_in*)sp)->sin_addr = a.a4;
+		/* ((struct sockaddr_in*)sp)->sin_port = */
+		return 0; /* success */
+	}
+	return 1;
+}
+
+int xsocket_stream_ip4or6(sa_family_t *fp)
+{
+	int fd;
+#if ENABLE_FEATURE_IPV6
+	fd = socket(AF_INET6, SOCK_STREAM, 0);
+	if (fp) *fp = AF_INET6;
+	if (fd < 0)
+#endif
+	{
+		fd = xsocket(AF_INET, SOCK_STREAM, 0);
+		if (fp) *fp = AF_INET;
+	}
+	return fd;
+}
+
+int create_and_bind_socket_ip4or6(const char *hostaddr, int port)
+{
+	static const int on = 1;
+	int fd;
+	sockaddr_inet sa;
+
+	memset(&sa, 0, sizeof(sa));
+	if (hostaddr) {
+		if (dotted2sockaddr(hostaddr, &sa.sa, sizeof(sa)))
+			bb_error_msg_and_die("bad address '%s'", hostaddr);
+		/* user specified bind addr dictates family */
+		fd = xsocket(sa.sa.sa_family, SOCK_STREAM, 0);
+	} else 
+		fd = xsocket_stream_ip4or6(&sa.sa.sa_family);
+	setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
+
+	/* if (port >= 0) { */
+#if ENABLE_FEATURE_IPV6
+		if (sa.sa.sa_family == AF_INET6 /* && !sa.sin6.sin6_port */)
+			sa.sin6.sin6_port = htons(port);
+#endif
+		if (sa.sa.sa_family == AF_INET /* && !sa.sin.sin_port */)
+			sa.sin.sin_port = htons(port);
+	/* } */
+
+	xbind(fd, &sa.sa, sizeof(sa));
+	return fd;
+}