diff options
Diffstat (limited to 'src/net/Resolver.cxx')
| -rw-r--r-- | src/net/Resolver.cxx | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/src/net/Resolver.cxx b/src/net/Resolver.cxx new file mode 100644 index 000000000..19df84096 --- /dev/null +++ b/src/net/Resolver.cxx @@ -0,0 +1,190 @@ +/* + * Copyright (C) 2003-2015 The Music Player Daemon Project + * http://www.musicpd.org + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include "config.h" +#include "Resolver.hxx" +#include "SocketAddress.hxx" +#include "util/Error.hxx" +#include "util/Domain.hxx" + +#include <algorithm> + +#ifndef WIN32 +#include <sys/socket.h> +#include <netdb.h> +#ifdef HAVE_TCP +#include <netinet/in.h> +#endif +#else +#include <ws2tcpip.h> +#include <winsock.h> +#endif + +#ifdef HAVE_UN +#include <sys/un.h> +#endif + +#include <string.h> +#include <stdio.h> + +const Domain resolver_domain("resolver"); + +#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 + +std::string +sockaddr_to_string(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) + const struct sockaddr_in6 *a6 = (const struct sockaddr_in6 *) + address.GetAddress(); + struct sockaddr_in a4; +#endif + int ret; + char host[NI_MAXHOST], serv[NI_MAXSERV]; + +#if defined(HAVE_IPV6) && defined(IN6_IS_ADDR_V4MAPPED) + if (address.GetFamily() == AF_INET6 && + IN6_IS_ADDR_V4MAPPED(&a6->sin6_addr)) { + /* convert "::ffff:127.0.0.1" to "127.0.0.1" */ + + memset(&a4, 0, sizeof(a4)); + a4.sin_family = AF_INET; + memcpy(&a4.sin_addr, ((const char *)&a6->sin6_addr) + 12, + sizeof(a4.sin_addr)); + a4.sin_port = a6->sin6_port; + + address = { (const struct sockaddr *)&a4, sizeof(a4) }; + } +#endif + + 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; +} + +struct addrinfo * +resolve_host_port(const char *host_port, unsigned default_port, + int flags, int socktype, + Error &error) +{ + std::string p(host_port); + const char *host = p.c_str(), *port = nullptr; + + if (host_port[0] == '[') { + /* IPv6 needs enclosing square braces, to + differentiate between IP colons and the port + separator */ + + size_t q = p.find(']', 1); + if (q != p.npos && p[q + 1] == ':' && p[q + 2] != 0) { + p[q] = 0; + port = host + q + 2; + ++host; + } + } + + if (port == nullptr) { + /* port is after the colon, but only if it's the only + colon (don't split IPv6 addresses) */ + + auto q = p.find(':'); + if (q != p.npos && p[q + 1] != 0 && + p.find(':', q + 1) == p.npos) { + p[q] = 0; + port = host + q + 1; + } + } + + char buffer[32]; + if (port == nullptr && default_port != 0) { + snprintf(buffer, sizeof(buffer), "%u", default_port); + port = buffer; + } + + if ((flags & AI_PASSIVE) != 0 && strcmp(host, "*") == 0) + host = nullptr; + + addrinfo hints; + memset(&hints, 0, sizeof(hints)); + hints.ai_flags = flags; + hints.ai_family = AF_UNSPEC; + hints.ai_socktype = socktype; + + struct addrinfo *ai; + int ret = getaddrinfo(host, port, &hints, &ai); + if (ret != 0) { + error.Format(resolver_domain, ret, + "Failed to look up '%s': %s", + host_port, gai_strerror(ret)); + return nullptr; + } + + return ai; +} |