mpd/src/listen.c
Max Kellermann 4d72bda4c3 listen: set file mode 666 on the unix socket
Depending on MPD's umask, the file permissions of the unix socket were
too restrictive, and many clients were not able to connect.  Do a
chmod(0666) on the socket, to allow everybody to connect.
2008-10-30 18:03:18 +01:00

307 lines
7.4 KiB
C

/* the Music Player Daemon (MPD)
* Copyright (C) 2003-2007 by Warren Dukes (warren.dukes@gmail.com)
* This project's homepage is: 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "listen.h"
#include "client.h"
#include "conf.h"
#include "log.h"
#include "utils.h"
#include "os_compat.h"
#include "../config.h"
#define MAXHOSTNAME 1024
#define ALLOW_REUSE 1
#define DEFAULT_PORT 6600
#define BINDERROR() do { \
FATAL("unable to bind port %u: %s\n" \
"maybe MPD is still running?\n", \
port, strerror(errno)); \
} while (0);
static int *listenSockets;
static int numberOfListenSockets;
int boundPort;
/*
* redirect stdin to /dev/null to work around a libao bug
* there are likely other bugs in other libraries (and even our code!)
* that check for fd > 0, so it's easiest to just keep
* fd = 0 == /dev/null for now...
*/
static void redirect_stdin(void)
{
int fd, st;
struct stat ss;
if ((st = fstat(STDIN_FILENO, &ss)) < 0) {
if ((fd = open("/dev/null", O_RDONLY) > 0)) {
DEBUG("stdin closed, and could not open /dev/null "
"as fd=0, some external library bugs "
"may be exposed...\n");
close(fd);
}
return;
}
if (!isatty(STDIN_FILENO))
return;
if ((fd = open("/dev/null", O_RDONLY)) < 0)
FATAL("failed to open /dev/null %s\n", strerror(errno));
if (dup2(fd, STDIN_FILENO) < 0)
FATAL("dup2 stdin: %s\n", strerror(errno));
}
static int establishListen(int pf, const struct sockaddr *addrp,
socklen_t addrlen)
{
int sock;
int allowReuse = ALLOW_REUSE;
#ifdef HAVE_STRUCT_UCRED
int passcred = 1;
#endif
if ((sock = socket(pf, SOCK_STREAM, 0)) < 0)
FATAL("socket < 0\n");
if (set_nonblocking(sock) < 0) {
FATAL("problems setting nonblocking on listen socket: %s\n",
strerror(errno));
}
if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (char *)&allowReuse,
sizeof(allowReuse)) < 0) {
FATAL("problems setsockopt'ing: %s\n", strerror(errno));
}
if (bind(sock, addrp, addrlen) < 0) {
close(sock);
return -1;
}
if (listen(sock, 5) < 0)
FATAL("problems listen'ing: %s\n", strerror(errno));
#ifdef HAVE_STRUCT_UCRED
setsockopt(sock, SOL_SOCKET, SO_PASSCRED, &passcred, sizeof(passcred));
#endif
numberOfListenSockets++;
listenSockets =
xrealloc(listenSockets, sizeof(int) * numberOfListenSockets);
listenSockets[numberOfListenSockets - 1] = sock;
return 0;
}
static void parseListenConfigParam(unsigned int port, ConfigParam * param)
{
const struct sockaddr *addrp;
socklen_t addrlen;
#ifdef HAVE_TCP
struct sockaddr_in sin4;
#ifdef HAVE_IPV6
struct sockaddr_in6 sin6;
int useIpv6 = ipv6Supported();
memset(&sin6, 0, sizeof(struct sockaddr_in6));
sin6.sin6_port = htons(port);
sin6.sin6_family = AF_INET6;
#endif
memset(&sin4, 0, sizeof(struct sockaddr_in));
sin4.sin_port = htons(port);
sin4.sin_family = AF_INET;
#endif /* HAVE_TCP */
if (!param || 0 == strcmp(param->value, "any")) {
#ifdef HAVE_TCP
DEBUG("binding to any address\n");
#ifdef HAVE_IPV6
if (useIpv6) {
sin6.sin6_addr = in6addr_any;
addrp = (const struct sockaddr *)&sin6;
addrlen = sizeof(struct sockaddr_in6);
if (establishListen(PF_INET6, addrp, addrlen) < 0)
BINDERROR();
}
#endif
sin4.sin_addr.s_addr = INADDR_ANY;
addrp = (const struct sockaddr *)&sin4;
addrlen = sizeof(struct sockaddr_in);
#ifdef HAVE_IPV6
if ((establishListen(PF_INET, addrp, addrlen) < 0) && !useIpv6) {
#else
if (establishListen(PF_INET, addrp, addrlen) < 0) {
#endif
BINDERROR();
}
#else /* HAVE_TCP */
FATAL("TCP support is disabled\n");
#endif /* HAVE_TCP */
#ifdef HAVE_UN
} else if (param->value[0] == '/') {
size_t path_length;
struct sockaddr_un sun;
path_length = strlen(param->value);
if (path_length >= sizeof(sun.sun_path))
FATAL("unix socket path is too long\n");
unlink(param->value);
sun.sun_family = AF_UNIX;
memcpy(sun.sun_path, param->value, path_length + 1);
addrp = (const struct sockaddr *)&sun;
addrlen = sizeof(sun);
if (establishListen(PF_UNIX, addrp, addrlen) < 0)
FATAL("unable to bind to %s: %s\n",
param->value, strerror(errno));
/* allow everybody to connect */
chmod(param->value, 0666);
#endif /* HAVE_UN */
} else {
#ifdef HAVE_TCP
struct addrinfo hints, *ai, *i;
char service[20];
int ret;
DEBUG("binding to address for %s\n", param->value);
memset(&hints, 0, sizeof(hints));
hints.ai_flags = AI_ADDRCONFIG;
hints.ai_family = PF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
hints.ai_protocol = IPPROTO_TCP;
snprintf(service, sizeof(service), "%u", port);
ret = getaddrinfo(param->value, service, &hints, &ai);
if (ret != 0)
FATAL("can't lookup host \"%s\" at line %i: %s\n",
param->value, param->line, gai_strerror(ret));
for (i = ai; i != NULL; i = i->ai_next)
if (establishListen(i->ai_family, i->ai_addr,
i->ai_addrlen) < 0)
BINDERROR();
freeaddrinfo(ai);
#else /* HAVE_TCP */
FATAL("TCP support is disabled\n");
#endif /* HAVE_TCP */
}
}
void listenOnPort(void)
{
int port = DEFAULT_PORT;
ConfigParam *param = getNextConfigParam(CONF_BIND_TO_ADDRESS, NULL);
ConfigParam *portParam = getConfigParam(CONF_PORT);
if (portParam) {
char *test;
port = strtol(portParam->value, &test, 10);
if (port <= 0 || *test != '\0') {
FATAL("%s \"%s\" specified at line %i is not a "
"positive integer", CONF_PORT,
portParam->value, portParam->line);
}
}
boundPort = port;
redirect_stdin();
do {
parseListenConfigParam(port, param);
} while ((param = getNextConfigParam(CONF_BIND_TO_ADDRESS, param)));
}
void addListenSocketsToFdSet(fd_set * fds, int *fdmax)
{
int i;
for (i = 0; i < numberOfListenSockets; i++) {
FD_SET(listenSockets[i], fds);
if (listenSockets[i] > *fdmax)
*fdmax = listenSockets[i];
}
}
void closeAllListenSockets(void)
{
int i;
DEBUG("closeAllListenSockets called\n");
for (i = 0; i < numberOfListenSockets; i++) {
DEBUG("closing listen socket %i\n", i);
while (close(listenSockets[i]) < 0 && errno == EINTR) ;
}
freeAllListenSockets();
}
void freeAllListenSockets(void)
{
numberOfListenSockets = 0;
free(listenSockets);
listenSockets = NULL;
}
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
(void)fd;
return -1;
#endif
}
void getConnections(fd_set * fds)
{
int i;
int fd = 0;
struct sockaddr sockAddr;
socklen_t socklen = sizeof(sockAddr);
for (i = 0; i < numberOfListenSockets; i++) {
if (FD_ISSET(listenSockets[i], fds)) {
if ((fd = accept(listenSockets[i], &sockAddr, &socklen))
>= 0) {
client_new(fd, &sockAddr, get_remote_uid(fd));
} else if (fd < 0
&& (errno != EAGAIN && errno != EINTR)) {
ERROR("Problems accept()'ing\n");
}
}
}
}