1 files changed, 152 insertions, 0 deletions
diff --git a/src/net/ToString.cxx b/src/net/ToString.cxx
new file mode 100644
index 000000000..1acf0320b
--- /dev/null
+++ b/src/net/ToString.cxx
@@ -0,0 +1,152 @@
+/*
+ * Copyright (C) 2011-2015 Max Kellermann <max@duempel.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
+ * FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+#include "ToString.hxx"
+#include "Features.hxx"
+#include "SocketAddress.hxx"
+
+#include <algorithm>
+
+#ifdef WIN32
+#include <ws2tcpip.h>
+#else
+#include <netdb.h>
+#ifdef HAVE_TCP
+#include <netinet/in.h>
+#endif
+#endif
+
+#ifdef HAVE_UN
+#include <sys/un.h>
+#endif
+
+#include <assert.h>
+#include <string.h>
+
+#ifdef HAVE_UN
+
+static std::string
+LocalAddressToString(const struct sockaddr_un &s_un, size_t size)
+{
+	const size_t prefix_size = (size_t)
+		((struct sockaddr_un *)nullptr)->sun_path;
+	assert(size >= prefix_size);
+
+	size_t result_length = size - prefix_size;
+
+	/* remove the trailing null terminator */
+	if (result_length > 0 && s_un.sun_path[result_length - 1] == 0)
+		--result_length;
+
+	if (result_length == 0)
+		return "local";
+
+	std::string result(s_un.sun_path, result_length);
+
+	/* replace all null bytes with '@'; this also handles abstract
+	   addresses (Linux specific) */
+	std::replace(result.begin(), result.end(), '\0', '@');
+
+	return result;
+}
+
+#endif
+
+#if defined(HAVE_IPV6) && defined(IN6_IS_ADDR_V4MAPPED)
+
+gcc_pure
+static bool
+IsV4Mapped(SocketAddress address)
+{
+	if (address.GetFamily() != AF_INET6)
+		return false;
+
+	const auto &a6 = *(const struct sockaddr_in6 *)address.GetAddress();
+	return IN6_IS_ADDR_V4MAPPED(&a6.sin6_addr);
+}
+
+/**
+ * Convert "::ffff:127.0.0.1" to "127.0.0.1".
+ */
+static SocketAddress
+UnmapV4(SocketAddress src, struct sockaddr_in &buffer)
+{
+	assert(IsV4Mapped(src));
+
+	const auto &src6 = *(const struct sockaddr_in6 *)src.GetAddress();
+	memset(&buffer, 0, sizeof(buffer));
+	buffer.sin_family = AF_INET;
+	memcpy(&buffer.sin_addr, ((const char *)&src6.sin6_addr) + 12,
+	       sizeof(buffer.sin_addr));
+	buffer.sin_port = src6.sin6_port;
+
+	return { (const struct sockaddr *)&buffer, sizeof(buffer) };
+}
+
+#endif
+
+std::string
+ToString(SocketAddress address)
+{
+#ifdef HAVE_UN
+	if (address.GetFamily() == AF_UNIX)
+		/* return path of UNIX domain sockets */
+		return LocalAddressToString(*(const sockaddr_un *)address.GetAddress(),
+					    address.GetSize());
+#endif
+
+#if defined(HAVE_IPV6) && defined(IN6_IS_ADDR_V4MAPPED)
+	struct sockaddr_in in_buffer;
+	if (IsV4Mapped(address))
+		address = UnmapV4(address, in_buffer);
+#endif
+
+	char host[NI_MAXHOST], serv[NI_MAXSERV];
+	int ret = getnameinfo(address.GetAddress(), address.GetSize(),
+			      host, sizeof(host), serv, sizeof(serv),
+			      NI_NUMERICHOST|NI_NUMERICSERV);
+	if (ret != 0)
+		return "unknown";
+
+#ifdef HAVE_IPV6
+	if (strchr(host, ':') != nullptr) {
+		std::string result("[");
+		result.append(host);
+		result.append("]:");
+		result.append(serv);
+		return result;
+	}
+#endif
+
+	std::string result(host);
+	result.push_back(':');
+	result.append(serv);
+	return result;
+}