NetBSD/usr.sbin/nfsd/nfsd.c

580 lines
13 KiB
C

/* $NetBSD: nfsd.c,v 1.63 2014/12/05 19:24:41 christos Exp $ */
/*
* Copyright (c) 1989, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Rick Macklem at The University of Guelph.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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 <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1989, 1993, 1994\
The Regents of the University of California. All rights reserved.");
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)nfsd.c 8.9 (Berkeley) 3/29/95";
#else
__RCSID("$NetBSD: nfsd.c,v 1.63 2014/12/05 19:24:41 christos Exp $");
#endif
#endif /* not lint */
#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <sys/uio.h>
#include <sys/ucred.h>
#include <sys/mount.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <poll.h>
#include <rpc/rpc.h>
#include <rpc/pmap_clnt.h>
#include <rpc/pmap_prot.h>
#include <nfs/rpcv2.h>
#include <nfs/nfsproto.h>
#include <nfs/nfs.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <grp.h>
#include <paths.h>
#include <pwd.h>
#include <pthread.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include <netdb.h>
/* Global defs */
#ifdef DEBUG
#define syslog(e, s, args...) \
do { \
fprintf(stderr,(s), ## args); \
fprintf(stderr, "\n"); \
} while (/*CONSTCOND*/0)
static int debug = 1;
#else
static int debug = 0;
#endif
static void nonfs(int);
__dead static void usage(void);
static void *
worker(void *dummy)
{
struct nfsd_srvargs nsd;
int nfssvc_flag;
pthread_setname_np(pthread_self(), "slave", NULL);
nfssvc_flag = NFSSVC_NFSD;
memset(&nsd, 0, sizeof(nsd));
while (nfssvc(nfssvc_flag, &nsd) < 0) {
if (errno != ENEEDAUTH) {
syslog(LOG_ERR, "nfssvc: %m");
exit(1);
}
nfssvc_flag = NFSSVC_NFSD | NFSSVC_AUTHINFAIL;
}
return NULL;
}
struct conf {
struct addrinfo *ai;
struct netconfig *nc;
struct netbuf nb;
struct pollfd pfd;
};
#define NFS_UDP4 0
#define NFS_TCP4 1
#define NFS_UDP6 2
#define NFS_TCP6 3
static int cfg_family[] = { PF_INET, PF_INET, PF_INET6, PF_INET6 };
static const char *cfg_netconf[] = { "udp", "tcp", "udp6", "tcp6" };
static int cfg_socktype[] = {
SOCK_DGRAM, SOCK_STREAM, SOCK_DGRAM, SOCK_STREAM };
static int cfg_protocol[] = {
IPPROTO_UDP, IPPROTO_TCP, IPPROTO_UDP, IPPROTO_TCP };
static int
tryconf(struct conf *cfg, int t, int reregister)
{
struct addrinfo hints;
int ecode;
memset(&hints, 0, sizeof hints);
hints.ai_flags = AI_PASSIVE;
hints.ai_family = cfg_family[t];
hints.ai_socktype = cfg_socktype[t];
hints.ai_protocol = cfg_protocol[t];
ecode = getaddrinfo(NULL, "nfs", &hints, &cfg->ai);
if (ecode != 0) {
syslog(LOG_ERR, "getaddrinfo %s: %s", cfg_netconf[t],
gai_strerror(ecode));
return -1;
}
cfg->nc = getnetconfigent(cfg_netconf[t]);
if (cfg->nc == NULL) {
syslog(LOG_ERR, "getnetconfigent %s failed: %m",
cfg_netconf[t]);
goto out;
}
cfg->nb.buf = cfg->ai->ai_addr;
cfg->nb.len = cfg->nb.maxlen = cfg->ai->ai_addrlen;
if (reregister)
if (!rpcb_set(RPCPROG_NFS, 2, cfg->nc, &cfg->nb)) {
syslog(LOG_ERR, "rpcb_set %s failed", cfg_netconf[t]);
goto out1;
}
return 0;
out1:
freenetconfigent(cfg->nc);
cfg->nc = NULL;
out:
freeaddrinfo(cfg->ai);
cfg->ai = NULL;
return -1;
}
static int
setupsock(struct conf *cfg, struct pollfd *set, int p)
{
int sock;
struct nfsd_args nfsdargs;
struct addrinfo *ai = cfg->ai;
int on = 1;
sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
if (sock == -1) {
syslog(LOG_ERR, "can't create %s socket: %m", cfg_netconf[p]);
return -1;
}
if (cfg_family[p] == PF_INET6) {
if (setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &on,
sizeof(on)) == -1) {
syslog(LOG_ERR, "can't set v6-only binding for %s "
"socket: %m", cfg_netconf[p]);
goto out;
}
}
if (cfg_protocol[p] == IPPROTO_TCP) {
if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &on,
sizeof(on)) == -1) {
syslog(LOG_ERR, "setsockopt SO_REUSEADDR for %s: %m",
cfg_netconf[p]);
goto out;
}
}
if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
syslog(LOG_ERR, "can't bind %s addr: %m", cfg_netconf[p]);
goto out;
}
if (cfg_protocol[p] == IPPROTO_TCP) {
if (listen(sock, 5) == -1) {
syslog(LOG_ERR, "listen failed");
goto out;
}
}
if (!rpcb_set(RPCPROG_NFS, 2, cfg->nc, &cfg->nb) ||
!rpcb_set(RPCPROG_NFS, 3, cfg->nc, &cfg->nb)) {
syslog(LOG_ERR, "can't register with %s portmap",
cfg_netconf[p]);
goto out;
}
if (cfg_protocol[p] == IPPROTO_TCP)
set->fd = sock;
else {
nfsdargs.sock = sock;
nfsdargs.name = NULL;
nfsdargs.namelen = 0;
if (nfssvc(NFSSVC_ADDSOCK, &nfsdargs) < 0) {
syslog(LOG_ERR, "can't add %s socket", cfg_netconf[p]);
goto out;
}
(void)close(sock);
}
return 0;
out:
(void)close(sock);
return -1;
}
/*
* The functions daemon2_fork() and daemon2_detach() below provide
* functionality similar to daemon(3) but split into two phases.
* daemon2_fork() is called early, before creating resources that
* cannot be inherited across a fork, such as threads or kqueues.
* When the daemon is ready to provide service, daemon2_detach()
* is called to complete the daemonization and signal the parent
* process to exit.
*
* These functions could potentially be moved to a library and
* shared by other daemons.
*
* The return value from daemon2_fork() is a file descriptor to
* be passed as the first argument to daemon2_detach().
*/
static int
daemon2_fork(void)
{
int i;
int fd;
int r;
pid_t pid;
int detach_msg_pipe[2];
/*
* Set up a pipe for singalling the parent, making sure the
* write end does not get allocated one of the file
* descriptors that may be closed in daemon2_detach(). The
* read end does not need such protection.
*/
for (i = 0; i < 3; i++) {
r = pipe2(detach_msg_pipe, O_CLOEXEC|O_NOSIGPIPE);
if (r < 0)
return -1;
if (detach_msg_pipe[1] <= STDERR_FILENO &&
(fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) {
(void)dup2(fd, detach_msg_pipe[0]);
(void)dup2(fd, detach_msg_pipe[1]);
if (fd > STDERR_FILENO)
(void)close(fd);
continue;
}
break;
}
pid = fork();
switch (pid) {
case -1:
return -1;
case 0:
/* child */
(void)close(detach_msg_pipe[0]);
return detach_msg_pipe[1];
default:
break;
}
/* Parent */
(void)close(detach_msg_pipe[1]);
for (;;) {
ssize_t nread;
char dummy;
nread = read(detach_msg_pipe[0], &dummy, 1);
if (nread < 0) {
if (errno == EINTR)
continue;
_exit(1);
} else if (nread == 0) {
_exit(1);
} else { /* nread > 0 */
_exit(0);
}
}
}
static int
daemon2_detach(int parentfd, int nochdir, int noclose)
{
int fd;
if (setsid() == -1)
return -1;
if (!nochdir)
(void)chdir("/");
if (!noclose && (fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) {
(void)dup2(fd, STDIN_FILENO);
(void)dup2(fd, STDOUT_FILENO);
(void)dup2(fd, STDERR_FILENO);
if (fd > STDERR_FILENO)
(void)close(fd);
}
while (1) {
ssize_t r = write(parentfd, "", 1);
if (r < 0) {
if (errno == EINTR)
continue;
else if (errno == EPIPE)
break;
else
return -1;
} else if (r == 0) {
/* Should not happen */
return -1;
} else {
break;
}
}
(void)close(parentfd);
return 0;
}
/*
* Nfs server daemon mostly just a user context for nfssvc()
*
* 1 - do file descriptor and signal cleanup
* 2 - create the nfsd thread(s)
* 3 - create server socket(s)
* 4 - register socket with portmap
*
* For connectionless protocols, just pass the socket into the kernel via
* nfssvc().
* For connection based sockets, loop doing accepts. When you get a new
* socket from accept, pass the msgsock into the kernel via nfssvc().
* The arguments are:
* -r - reregister with portmapper
* -t - support only tcp nfs clients
* -u - support only udp nfs clients
* -n num how many threads to create.
* -4 - use only ipv4
* -6 - use only ipv6
*/
int
main(int argc, char *argv[])
{
struct conf cfg[4];
struct pollfd set[__arraycount(cfg)];
int ch, connect_type_cnt;
size_t i, nfsdcnt;
int reregister;
int tcpflag, udpflag;
int ip6flag, ip4flag;
int s, compat;
int parent_fd = -1;
#define DEFNFSDCNT 4
nfsdcnt = DEFNFSDCNT;
compat = reregister = 0;
tcpflag = udpflag = 1;
ip6flag = ip4flag = 1;
#define GETOPT "46n:rtu"
#define USAGE "[-46rtu] [-n num_servers]"
while ((ch = getopt(argc, argv, GETOPT)) != -1) {
switch (ch) {
case '6':
ip6flag = 1;
ip4flag = 0;
s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_UDP);
if (s < 0 && (errno == EPROTONOSUPPORT ||
errno == EPFNOSUPPORT || errno == EAFNOSUPPORT))
ip6flag = 0;
else
close(s);
break;
case '4':
ip6flag = 0;
ip4flag = 1;
s = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
if (s < 0 && (errno == EPROTONOSUPPORT ||
errno == EPFNOSUPPORT || errno == EAFNOSUPPORT))
ip4flag = 0;
else
close(s);
break;
case 'n':
nfsdcnt = atoi(optarg);
if (nfsdcnt < 1) {
warnx("nfsd count %zu; reset to %d", nfsdcnt,
DEFNFSDCNT);
nfsdcnt = DEFNFSDCNT;
}
break;
case 'r':
reregister = 1;
break;
case 't':
compat |= 2;
tcpflag = 1;
udpflag = 0;
break;
case 'u':
compat |= 1;
tcpflag = 0;
udpflag = 1;
break;
default:
case '?':
usage();
}
}
argv += optind;
argc -= optind;
if (compat == 3) {
warnx("Old -tu options detected; enabling both udp and tcp.");
warnx("This is the default behavior now and you can remove");
warnx("all options.");
tcpflag = udpflag = 1;
if (ip6flag == 1 && ip4flag == 0)
ip4flag = 1;
}
if (debug == 0) {
parent_fd = daemon2_fork();
}
openlog("nfsd", LOG_PID, LOG_DAEMON);
memset(cfg, 0, sizeof(cfg));
for (i = 0; i < __arraycount(cfg); i++) {
if (ip4flag == 0 && cfg_family[i] == PF_INET)
continue;
if (ip6flag == 0 && cfg_family[i] == PF_INET6)
continue;
if (tcpflag == 0 && cfg_protocol[i] == IPPROTO_TCP)
continue;
if (udpflag == 0 && cfg_protocol[i] == IPPROTO_UDP)
continue;
tryconf(&cfg[i], i, reregister);
}
for (i = 0; i < nfsdcnt; i++) {
pthread_t t;
int error;
error = pthread_create(&t, NULL, worker, NULL);
if (error) {
errno = error;
syslog(LOG_ERR, "pthread_create: %m");
exit(1);
}
}
connect_type_cnt = 0;
for (i = 0; i < __arraycount(cfg); i++) {
set[i].fd = -1;
set[i].events = POLLIN;
set[i].revents = 0;
if (cfg[i].nc == NULL)
continue;
setupsock(&cfg[i], &set[i], i);
if (set[i].fd != -1)
connect_type_cnt++;
}
if (connect_type_cnt == 0)
exit(0);
pthread_setname_np(pthread_self(), "master", NULL);
if (debug == 0) {
daemon2_detach(parent_fd, 0, 0);
(void)signal(SIGHUP, SIG_IGN);
(void)signal(SIGINT, SIG_IGN);
(void)signal(SIGQUIT, SIG_IGN);
(void)signal(SIGSYS, nonfs);
}
/*
* Loop forever accepting connections and passing the sockets
* into the kernel for the mounts.
*/
for (;;) {
if (poll(set, __arraycount(set), INFTIM) == -1) {
syslog(LOG_ERR, "poll failed: %m");
exit(1);
}
for (i = 0; i < __arraycount(set); i++) {
struct nfsd_args nfsdargs;
struct sockaddr_storage ss;
socklen_t len;
int msgsock;
int on = 1;
if ((set[i].revents & POLLIN) == 0)
continue;
len = sizeof(ss);
if ((msgsock = accept(set[i].fd,
(struct sockaddr *)&ss, &len)) == -1) {
int serrno = errno;
syslog(LOG_ERR, "accept failed: %m");
if (serrno == EINTR || serrno == ECONNABORTED)
continue;
exit(1);
}
if (setsockopt(msgsock, SOL_SOCKET, SO_KEEPALIVE, &on,
sizeof(on)) == -1)
syslog(LOG_ERR, "setsockopt SO_KEEPALIVE: %m");
nfsdargs.sock = msgsock;
nfsdargs.name = (void *)&ss;
nfsdargs.namelen = len;
nfssvc(NFSSVC_ADDSOCK, &nfsdargs);
(void)close(msgsock);
}
}
}
static void
usage(void)
{
(void)fprintf(stderr, "Usage: %s %s\n", getprogname(), USAGE);
exit(1);
}
static void
nonfs(int signo)
{
syslog(LOG_ERR, "missing system call: NFS not available.");
}