mpd/src/listen.c
Andreas Vögele dda5415def Make get_remote_uid() work on BSD
I've attached a patch that will make file URIs work on operating systems
that provide the getpeereid() function call to check the user ID of the
peer connected to a UNIX domain socket.
2010-06-19 13:47:10 +02:00

450 lines
10 KiB
C

/*
* 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 "listen.h"
#include "socket_util.h"
#include "client.h"
#include "conf.h"
#include "fd_util.h"
#include "glib_compat.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <assert.h>
#ifdef WIN32
#define WINVER 0x0501
#include <ws2tcpip.h>
#include <winsock.h>
#else
#include <netinet/in.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <netdb.h>
#endif
#undef G_LOG_DOMAIN
#define G_LOG_DOMAIN "listen"
#define DEFAULT_PORT 6600
struct listen_socket {
struct listen_socket *next;
int fd;
guint source_id;
};
static struct listen_socket *listen_sockets;
int listen_port;
static GQuark
listen_quark(void)
{
return g_quark_from_static_string("listen");
}
static gboolean
listen_in_event(GIOChannel *source, GIOCondition condition, gpointer data);
static bool
listen_add_address(int pf, const struct sockaddr *addrp, socklen_t addrlen,
GError **error)
{
char *address_string;
int fd;
struct listen_socket *ls;
GIOChannel *channel;
address_string = sockaddr_to_string(addrp, addrlen, NULL);
if (address_string != NULL) {
g_debug("binding to socket address %s", address_string);
g_free(address_string);
}
fd = socket_bind_listen(pf, SOCK_STREAM, 0, addrp, addrlen, 5, error);
if (fd < 0)
return false;
ls = g_new(struct listen_socket, 1);
ls->fd = fd;
channel = g_io_channel_unix_new(fd);
ls->source_id = g_io_add_watch(channel, G_IO_IN,
listen_in_event, GINT_TO_POINTER(fd));
g_io_channel_unref(channel);
ls->next = listen_sockets;
listen_sockets = ls;
return true;
}
#ifdef HAVE_TCP
/**
* Add a listener on a port on all IPv4 interfaces.
*
* @param port the TCP port
* @param error location to store the error occuring, or NULL to ignore errors
* @return true on success
*/
static bool
listen_add_port_ipv4(unsigned int port, GError **error)
{
struct sockaddr_in sin;
const struct sockaddr *addrp = (const struct sockaddr *)&sin;
socklen_t addrlen = sizeof(sin);
memset(&sin, 0, sizeof(sin));
sin.sin_port = htons(port);
sin.sin_family = AF_INET;
sin.sin_addr.s_addr = INADDR_ANY;
return listen_add_address(PF_INET, addrp, addrlen, error);
}
#ifdef HAVE_IPV6
/**
* Add a listener on a port on all IPv6 interfaces.
*
* @param port the TCP port
* @param error location to store the error occuring, or NULL to ignore errors
* @return true on success
*/
static bool
listen_add_port_ipv6(unsigned int port, GError **error)
{
struct sockaddr_in6 sin;
const struct sockaddr *addrp = (const struct sockaddr *)&sin;
socklen_t addrlen = sizeof(sin);
memset(&sin, 0, sizeof(sin));
sin.sin6_port = htons(port);
sin.sin6_family = AF_INET6;
return listen_add_address(PF_INET6, addrp, addrlen, error);
}
#endif /* HAVE_IPV6 */
#endif /* HAVE_TCP */
/**
* Add a listener on a port on all interfaces.
*
* @param port the TCP port
* @param error location to store the error occuring, or NULL to ignore errors
* @return true on success
*/
static bool
listen_add_port(unsigned int port, GError **error)
{
#ifdef HAVE_TCP
bool success;
#ifdef HAVE_IPV6
bool success6;
GError *error2 = NULL;
#endif
g_debug("binding to any address");
#ifdef HAVE_IPV6
success6 = listen_add_port_ipv6(port, &error2);
if (!success6) {
if (error2->domain != listen_quark() ||
(error2->code != EAFNOSUPPORT && error2->code != EINVAL &&
error2->code != EPROTONOSUPPORT)) {
g_propagate_error(error, error2);
return false;
}
/* although MPD was compiled with IPv6 support, this
host does not have it - ignore this error */
g_error_free(error2);
}
#endif
success = listen_add_port_ipv4(port, error);
if (!success) {
#ifdef HAVE_IPV6
if (success6)
/* non-critical: IPv6 listener is
already set up */
g_clear_error(error);
else
#endif
return false;
}
return true;
#else /* HAVE_TCP */
(void)port;
g_set_error(error, listen_quark(), 0,
"TCP support is disabled");
return false;
#endif /* HAVE_TCP */
}
/**
* Resolves a host name, and adds listeners on all addresses in the
* result set.
*
* @param hostname the host name to be resolved
* @param port the TCP port
* @param error location to store the error occuring, or NULL to ignore errors
* @return true on success
*/
static bool
listen_add_host(const char *hostname, unsigned port, GError **error_r)
{
#ifdef HAVE_TCP
struct addrinfo hints, *ai, *i;
char service[20];
int ret;
bool success;
g_debug("binding to address for %s", hostname);
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;
g_snprintf(service, sizeof(service), "%u", port);
ret = getaddrinfo(hostname, service, &hints, &ai);
if (ret != 0) {
g_set_error(error_r, listen_quark(), ret,
"Failed to look up host \"%s\": %s",
hostname, gai_strerror(ret));
return false;
}
for (i = ai; i != NULL; i = i->ai_next) {
GError *error = NULL;
success = listen_add_address(i->ai_family, i->ai_addr,
i->ai_addrlen, &error);
if (!success) {
if (i == ai) {
/* first bind has failed: fatal
error */
g_propagate_error(error_r, error);
return false;
} else {
char *address_string =
sockaddr_to_string(i->ai_addr,
i->ai_addrlen,
NULL);
if (address_string == NULL)
address_string = g_strdup("[unknown]");
g_warning("bind to %s failed: %s "
"(continuing anyway, because at "
"least one address is bound)",
address_string, error->message);
g_free(address_string);
g_error_free(error);
}
}
}
freeaddrinfo(ai);
return true;
#else /* HAVE_TCP */
(void)hostname;
(void)port;
g_set_error(error_r, listen_quark(), 0,
"TCP support is disabled");
return false;
#endif /* HAVE_TCP */
}
#ifdef HAVE_UN
/**
* Add a listener on a Unix domain socket.
*
* @param path the absolute socket path
* @param error location to store the error occuring, or NULL to ignore errors
* @return true on success
*/
static bool
listen_add_path(const char *path, GError **error)
{
size_t path_length;
struct sockaddr_un s_un;
const struct sockaddr *addrp = (const struct sockaddr *)&s_un;
socklen_t addrlen = sizeof(s_un);
bool success;
path_length = strlen(path);
if (path_length >= sizeof(s_un.sun_path)) {
g_set_error(error, listen_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);
success = listen_add_address(PF_UNIX, addrp, addrlen, error);
if (!success)
return false;
/* allow everybody to connect */
chmod(path, 0666);
return true;
}
#endif /* HAVE_UN */
static bool
listen_add_config_param(unsigned int port,
const struct config_param *param,
GError **error)
{
assert(param != NULL);
if (0 == strcmp(param->value, "any")) {
return listen_add_port(port, error);
#ifdef HAVE_UN
} else if (param->value[0] == '/') {
return listen_add_path(param->value, error);
#endif /* HAVE_UN */
} else {
return listen_add_host(param->value, port, error);
}
}
bool
listen_global_init(GError **error_r)
{
int port = config_get_positive(CONF_PORT, DEFAULT_PORT);
const struct config_param *param =
config_get_next_param(CONF_BIND_TO_ADDRESS, NULL);
bool success;
GError *error = NULL;
if (param != NULL) {
/* "bind_to_address" is configured, create listeners
for all values */
do {
success = listen_add_config_param(port, param, &error);
if (!success) {
g_propagate_prefixed_error(error_r, error,
"Failed to listen on %s (line %i): ",
param->value, param->line);
return false;
}
param = config_get_next_param(CONF_BIND_TO_ADDRESS,
param);
} while (param != NULL);
} else {
/* no "bind_to_address" configured, bind the
configured port on all interfaces */
success = listen_add_port(port, &error);
if (!success) {
g_propagate_prefixed_error(error_r, error,
"Failed to listen on *:%d: ",
port);
return false;
}
}
listen_port = port;
return true;
}
void listen_global_finish(void)
{
g_debug("listen_global_finish called");
while (listen_sockets != NULL) {
struct listen_socket *ls = listen_sockets;
listen_sockets = ls->next;
g_source_remove(ls->source_id);
close(ls->fd);
g_free(ls);
}
}
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;
#endif
return -1;
#endif
}
static gboolean
listen_in_event(G_GNUC_UNUSED GIOChannel *source,
G_GNUC_UNUSED GIOCondition condition,
gpointer data)
{
int listen_fd = GPOINTER_TO_INT(data), fd;
struct sockaddr_storage sa;
size_t sa_length = sizeof(sa);
fd = accept_cloexec_nonblock(listen_fd, (struct sockaddr*)&sa,
&sa_length);
if (fd >= 0) {
client_new(fd, (struct sockaddr*)&sa, sa_length,
get_remote_uid(fd));
} else if (fd < 0 && errno != EINTR) {
g_warning("Problems accept()'ing");
}
return true;
}