From 18e3d0b50423dc49ed8f425bb291d8675b38b5f9 Mon Sep 17 00:00:00 2001 From: Max Kellermann Date: Tue, 5 Oct 2010 20:29:41 +0200 Subject: listen: move generic code to server_socket.c --- src/server_socket.c | 447 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 447 insertions(+) create mode 100644 src/server_socket.c (limited to 'src/server_socket.c') diff --git a/src/server_socket.c b/src/server_socket.c new file mode 100644 index 000000000..b0eb179a6 --- /dev/null +++ b/src/server_socket.c @@ -0,0 +1,447 @@ +/* + * Copyright (C) 2003-2010 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 "server_socket.h" +#include "socket_util.h" +#include "fd_util.h" +#include "glib_compat.h" + +#include +#include +#include +#include +#include +#include +#include +#include + +#ifdef WIN32 +#define WINVER 0x0501 +#include +#include +#else +#include +#include +#include +#include +#endif + +#undef G_LOG_DOMAIN +#define G_LOG_DOMAIN "listen" + +#define DEFAULT_PORT 6600 + +struct one_socket { + struct one_socket *next; + struct server_socket *parent; + + unsigned serial; + + int fd; + guint source_id; + + char *path; + + size_t address_length; + struct sockaddr address; +}; + +struct server_socket { + server_socket_callback_t callback; + void *callback_ctx; + + struct one_socket *sockets, **sockets_tail_r; + unsigned next_serial; +}; + +static GQuark +server_socket_quark(void) +{ + return g_quark_from_static_string("server_socket"); +} + +struct server_socket * +server_socket_new(server_socket_callback_t callback, void *callback_ctx) +{ + struct server_socket *ss = g_new(struct server_socket, 1); + ss->callback = callback; + ss->callback_ctx = callback_ctx; + ss->sockets = NULL; + ss->sockets_tail_r = &ss->sockets; + ss->next_serial = 1; + return ss; +} + +void +server_socket_free(struct server_socket *ss) +{ + server_socket_close(ss); + + while (ss->sockets != NULL) { + struct one_socket *s = ss->sockets; + ss->sockets = s->next; + + assert(s->fd < 0); + + g_free(s->path); + g_free(s); + } + + g_free(ss); +} + +/** + * Wraper for sockaddr_to_string() which never fails. + */ +static char * +one_socket_to_string(const struct one_socket *s) +{ + char *p = sockaddr_to_string(&s->address, s->address_length, NULL); + if (p == NULL) + p = g_strdup("[unknown]"); + return p; +} + +static int +get_remote_uid(int fd) +{ +#ifdef HAVE_STRUCT_UCRED + struct ucred cred; + socklen_t len = sizeof (cred); + + if (getsockopt(fd, SOL_SOCKET, SO_PEERCRED, &cred, &len) < 0) + return 0; + + return cred.uid; +#else +#ifdef HAVE_GETPEEREID + uid_t euid; + gid_t egid; + + if (getpeereid(fd, &euid, &egid) == 0) + return euid; +#else + (void)fd; +#endif + return -1; +#endif +} + +static gboolean +server_socket_in_event(G_GNUC_UNUSED GIOChannel *source, + G_GNUC_UNUSED GIOCondition condition, + gpointer data) +{ + struct one_socket *s = data; + + struct sockaddr_storage address; + size_t address_length = sizeof(address); + int fd = accept_cloexec_nonblock(s->fd, (struct sockaddr*)&address, + &address_length); + if (fd >= 0) + s->parent->callback(fd, (const struct sockaddr*)&address, + address_length, get_remote_uid(fd), + s->parent->callback_ctx); + else + g_warning("accept() failed: %s", g_strerror(errno)); + + return true; +} + +bool +server_socket_open(struct server_socket *ss, GError **error_r) +{ + struct one_socket *good = NULL, *bad = NULL; + GError *last_error = NULL; + + for (struct one_socket *s = ss->sockets; s != NULL; s = s->next) { + assert(s->serial > 0); + assert(good == NULL || s->serial >= good->serial); + assert(s->fd < 0); + + if (bad != NULL && s->serial != bad->serial) { + server_socket_close(ss); + g_propagate_error(error_r, last_error); + return false; + } + + GError *error = NULL; + s->fd = socket_bind_listen(s->address.sa_family, SOCK_STREAM, 0, + &s->address, s->address_length, 5, + &error); + if (s->fd < 0) { + if (good != NULL && good->serial == s->serial) { + char *address_string = one_socket_to_string(s); + char *good_string = one_socket_to_string(good); + g_warning("bind to '%s' failed: %s " + "(continuing anyway, because " + "binding to '%s' succeeded)", + address_string, error->message, + good_string); + g_free(address_string); + g_free(good_string); + g_error_free(error); + } else if (bad == NULL) { + bad = s; + + char *address_string = one_socket_to_string(s); + g_propagate_prefixed_error(&last_error, error, + "Failed to bind to '%s': ", + address_string); + g_free(address_string); + } else + g_error_free(error); + continue; + } + + /* allow everybody to connect */ + + if (s->path != NULL) + chmod(s->path, 0666); + + /* register in the GLib main loop */ + + GIOChannel *channel = g_io_channel_unix_new(s->fd); + s->source_id = g_io_add_watch(channel, G_IO_IN, + server_socket_in_event, s); + g_io_channel_unref(channel); + + /* mark this socket as "good", and clear previous + errors */ + + good = s; + + if (bad != NULL) { + bad = NULL; + g_error_free(last_error); + last_error = NULL; + } + } + + if (bad != NULL) { + server_socket_close(ss); + g_propagate_error(error_r, last_error); + return false; + } + + return true; +} + +void +server_socket_close(struct server_socket *ss) +{ + for (struct one_socket *s = ss->sockets; s != NULL; s = s->next) { + if (s->fd < 0) + continue; + + g_source_remove(s->source_id); + close(s->fd); + s->fd = -1; + } +} + +static struct one_socket * +one_socket_new(unsigned serial, const struct sockaddr *address, + size_t address_length) +{ + assert(address != NULL); + assert(address_length > 0); + + struct one_socket *s = g_malloc(sizeof(*s) - sizeof(s->address) + + address_length); + s->next = NULL; + s->serial = serial; + s->fd = -1; + s->path = NULL; + s->address_length = address_length; + memcpy(&s->address, address, address_length); + + return s; +} + +static struct one_socket * +server_socket_add_address(struct server_socket *ss, + const struct sockaddr *address, + size_t address_length) +{ + assert(ss != NULL); + assert(ss->sockets_tail_r != NULL); + assert(*ss->sockets_tail_r == NULL); + + struct one_socket *s = one_socket_new(ss->next_serial, + address, address_length); + s->parent = ss; + *ss->sockets_tail_r = s; + ss->sockets_tail_r = &s->next; + + return s; +} + +#ifdef HAVE_TCP + +/** + * Add a listener on a port on all IPv4 interfaces. + * + * @param port the TCP port + */ +static void +server_socket_add_port_ipv4(struct server_socket *ss, unsigned port) +{ + struct sockaddr_in sin; + memset(&sin, 0, sizeof(sin)); + sin.sin_port = htons(port); + sin.sin_family = AF_INET; + sin.sin_addr.s_addr = INADDR_ANY; + + server_socket_add_address(ss, (const struct sockaddr *)&sin, + sizeof(sin)); +} + +#ifdef HAVE_IPV6 +/** + * Add a listener on a port on all IPv6 interfaces. + * + * @param port the TCP port + */ +static void +server_socket_add_port_ipv6(struct server_socket *ss, unsigned port) +{ + struct sockaddr_in6 sin; + memset(&sin, 0, sizeof(sin)); + sin.sin6_port = htons(port); + sin.sin6_family = AF_INET6; + + server_socket_add_address(ss, (const struct sockaddr *)&sin, + sizeof(sin)); +} +#endif /* HAVE_IPV6 */ + +#endif /* HAVE_TCP */ + +bool +server_socket_add_port(struct server_socket *ss, unsigned port, + GError **error_r) +{ +#ifdef HAVE_TCP + if (port == 0 || port > 0xffff) { + g_set_error(error_r, server_socket_quark(), 0, + "Invalid TCP port"); + return false; + } + +#ifdef HAVE_IPV6 + server_socket_add_port_ipv6(ss, port); +#endif + server_socket_add_port_ipv4(ss, port); + + ++ss->next_serial; + + return true; +#else /* HAVE_TCP */ + (void)ss; + (void)port; + + g_set_error(error_r, server_socket_quark(), 0, + "TCP support is disabled"); + return false; +#endif /* HAVE_TCP */ +} + +bool +server_socket_add_host(struct server_socket *ss, const char *hostname, + unsigned port, GError **error_r) +{ +#ifdef HAVE_TCP + struct addrinfo hints; + memset(&hints, 0, sizeof(hints)); + hints.ai_flags = AI_PASSIVE; +#ifdef AI_ADDRCONFIG + hints.ai_flags |= AI_ADDRCONFIG; +#endif + hints.ai_family = PF_UNSPEC; + hints.ai_socktype = SOCK_STREAM; + hints.ai_protocol = IPPROTO_TCP; + + char service[20]; + g_snprintf(service, sizeof(service), "%u", port); + + struct addrinfo *ai; + int ret = getaddrinfo(hostname, service, &hints, &ai); + if (ret != 0) { + g_set_error(error_r, server_socket_quark(), ret, + "Failed to look up host \"%s\": %s", + hostname, gai_strerror(ret)); + return false; + } + + for (const struct addrinfo *i = ai; i != NULL; i = i->ai_next) + server_socket_add_address(ss, i->ai_addr, i->ai_addrlen); + + freeaddrinfo(ai); + + ++ss->next_serial; + + return true; +#else /* HAVE_TCP */ + (void)ss; + (void)hostname; + (void)port; + + g_set_error(error_r, server_socket_quark(), 0, + "TCP support is disabled"); + return false; +#endif /* HAVE_TCP */ +} + +bool +server_socket_add_path(struct server_socket *ss, const char *path, + GError **error_r) +{ +#ifdef HAVE_UN + struct sockaddr_un s_un; + + size_t path_length = strlen(path); + if (path_length >= sizeof(s_un.sun_path)) { + g_set_error(error_r, server_socket_quark(), 0, + "UNIX socket path is too long"); + return false; + } + + unlink(path); + + s_un.sun_family = AF_UNIX; + memcpy(s_un.sun_path, path, path_length + 1); + + struct one_socket *s = + server_socket_add_address(ss, (const struct sockaddr *)&s_un, + sizeof(s_un)); + s->path = g_strdup(path); + + return true; +#else /* !HAVE_UN */ + (void)ss; + (void)path; + + g_set_error(error_r, server_socket_quark(), 0, + "UNIX domain socket support is disabled"); + return false; +#endif /* !HAVE_UN */ +} + -- cgit v1.2.3