freebsd-skq/usr.sbin/nfsuserd/nfsuserd.c

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/*-
* Copyright (c) 2009 Rick Macklem, University of Guelph
* All rights reserved.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/errno.h>
#include <sys/linker.h>
#include <sys/module.h>
#include <sys/mount.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/time.h>
#include <sys/ucred.h>
#include <sys/vnode.h>
#include <sys/wait.h>
#include <nfs/nfssvc.h>
#include <rpc/rpc.h>
#include <fs/nfs/rpcv2.h>
#include <fs/nfs/nfsproto.h>
#include <fs/nfs/nfskpiport.h>
#include <fs/nfs/nfs.h>
#include <ctype.h>
#include <err.h>
#include <grp.h>
#include <netdb.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
/*
* This program loads the password and group databases into the kernel
* for NFS V4.
*/
static void cleanup_term(int);
static void usage(void);
static void nfsuserdsrv(struct svc_req *, SVCXPRT *);
static bool_t xdr_getid(XDR *, caddr_t);
static bool_t xdr_getname(XDR *, caddr_t);
static bool_t xdr_retval(XDR *, caddr_t);
#define MAXNAME 1024
#define MAXNFSUSERD 20
#define DEFNFSUSERD 4
#define MAXUSERMAX 100000
#define MINUSERMAX 10
#define DEFUSERMAX 200
#define DEFUSERTIMEOUT (1 * 60)
struct info {
long id;
long retval;
char name[MAXNAME + 1];
};
u_char *dnsname = "default.domain";
u_char *defaultuser = "nobody";
uid_t defaultuid = (uid_t)32767;
u_char *defaultgroup = "nogroup";
gid_t defaultgid = (gid_t)32767;
int verbose = 0, im_a_slave = 0, nfsuserdcnt = -1, forcestart = 0;
int defusertimeout = DEFUSERTIMEOUT;
pid_t slaves[MAXNFSUSERD];
int
main(int argc, char *argv[])
{
int i, j;
int error, fnd_dup, len, mustfreeai = 0, start_uidpos;
struct nfsd_idargs nid;
struct passwd *pwd;
struct group *grp;
int sock, one = 1;
SVCXPRT *udptransp;
u_short portnum;
sigset_t signew;
char hostname[MAXHOSTNAMELEN + 1], *cp;
struct addrinfo *aip, hints;
static uid_t check_dups[MAXUSERMAX];
if (modfind("nfscommon") < 0) {
/* Not present in kernel, try loading it */
if (kldload("nfscommon") < 0 ||
modfind("nfscommon") < 0)
errx(1, "Experimental nfs subsystem is not available");
}
/*
* First, figure out what our domain name and Kerberos Realm
* seem to be. Command line args may override these later.
*/
if (gethostname(hostname, MAXHOSTNAMELEN) == 0) {
if ((cp = strchr(hostname, '.')) != NULL &&
*(cp + 1) != '\0') {
dnsname = cp + 1;
} else {
memset((void *)&hints, 0, sizeof (hints));
hints.ai_flags = AI_CANONNAME;
error = getaddrinfo(hostname, NULL, &hints, &aip);
if (error == 0) {
if (aip->ai_canonname != NULL &&
(cp = strchr(aip->ai_canonname, '.')) != NULL
&& *(cp + 1) != '\0') {
dnsname = cp + 1;
mustfreeai = 1;
} else {
freeaddrinfo(aip);
}
}
}
}
nid.nid_usermax = DEFUSERMAX;
nid.nid_usertimeout = defusertimeout;
argc--;
argv++;
while (argc >= 1) {
if (!strcmp(*argv, "-domain")) {
if (argc == 1)
usage();
argc--;
argv++;
strncpy(hostname, *argv, MAXHOSTNAMELEN);
hostname[MAXHOSTNAMELEN] = '\0';
dnsname = hostname;
} else if (!strcmp(*argv, "-verbose")) {
verbose = 1;
} else if (!strcmp(*argv, "-force")) {
forcestart = 1;
} else if (!strcmp(*argv, "-usermax")) {
if (argc == 1)
usage();
argc--;
argv++;
i = atoi(*argv);
if (i < MINUSERMAX || i > MAXUSERMAX) {
fprintf(stderr,
"usermax %d out of range %d<->%d\n", i,
MINUSERMAX, MAXUSERMAX);
usage();
}
nid.nid_usermax = i;
} else if (!strcmp(*argv, "-usertimeout")) {
if (argc == 1)
usage();
argc--;
argv++;
i = atoi(*argv);
if (i < 0 || i > 100000) {
fprintf(stderr,
"usertimeout %d out of range 0<->100000\n",
i);
usage();
}
nid.nid_usertimeout = defusertimeout = i * 60;
} else if (nfsuserdcnt == -1) {
nfsuserdcnt = atoi(*argv);
if (nfsuserdcnt < 1)
usage();
if (nfsuserdcnt > MAXNFSUSERD) {
warnx("nfsuserd count %d; reset to %d",
nfsuserdcnt, DEFNFSUSERD);
nfsuserdcnt = DEFNFSUSERD;
}
} else {
usage();
}
argc--;
argv++;
}
if (nfsuserdcnt < 1)
nfsuserdcnt = DEFNFSUSERD;
/*
* Strip off leading and trailing '.'s in domain name and map
* alphabetics to lower case.
*/
while (*dnsname == '.')
dnsname++;
if (*dnsname == '\0')
errx(1, "Domain name all '.'");
len = strlen(dnsname);
cp = dnsname + len - 1;
while (*cp == '.') {
*cp = '\0';
len--;
cp--;
}
for (i = 0; i < len; i++) {
if (!isascii(dnsname[i]))
errx(1, "Domain name has non-ascii char");
if (isupper(dnsname[i]))
dnsname[i] = tolower(dnsname[i]);
}
/*
* If the nfsuserd died off ungracefully, this is necessary to
* get them to start again.
*/
if (forcestart && nfssvc(NFSSVC_NFSUSERDDELPORT, NULL) < 0)
errx(1, "Can't do nfssvc() to delete the port");
if (verbose)
fprintf(stderr,
"nfsuserd: domain=%s usermax=%d usertimeout=%d\n",
dnsname, nid.nid_usermax, nid.nid_usertimeout);
for (i = 0; i < nfsuserdcnt; i++)
slaves[i] = (pid_t)-1;
/*
* Set up the service port to accept requests via UDP from
* localhost (127.0.0.1).
*/
if ((sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0)
err(1, "cannot create udp socket");
/*
* Not sure what this does, so I'll leave it here for now.
*/
setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
if ((udptransp = svcudp_create(sock)) == NULL)
err(1, "Can't set up socket");
/*
* By not specifying a protocol, it is linked into the
* dispatch queue, but not registered with portmapper,
* which is just what I want.
*/
if (!svc_register(udptransp, RPCPROG_NFSUSERD, RPCNFSUSERD_VERS,
nfsuserdsrv, 0))
err(1, "Can't register nfsuserd");
/*
* Tell the kernel what my port# is.
*/
portnum = htons(udptransp->xp_port);
#ifdef DEBUG
printf("portnum=0x%x\n", portnum);
#else
if (nfssvc(NFSSVC_NFSUSERDPORT, (caddr_t)&portnum) < 0) {
if (errno == EPERM) {
fprintf(stderr,
"Can't start nfsuserd when already running");
fprintf(stderr,
" If not running, use the -force option.\n");
} else {
fprintf(stderr, "Can't do nfssvc() to add port\n");
}
exit(1);
}
#endif
pwd = getpwnam(defaultuser);
if (pwd)
nid.nid_uid = pwd->pw_uid;
else
nid.nid_uid = defaultuid;
grp = getgrnam(defaultgroup);
if (grp)
nid.nid_gid = grp->gr_gid;
else
nid.nid_gid = defaultgid;
nid.nid_name = dnsname;
nid.nid_namelen = strlen(nid.nid_name);
nid.nid_flag = NFSID_INITIALIZE;
#ifdef DEBUG
printf("Initialize uid=%d gid=%d dns=%s\n", nid.nid_uid, nid.nid_gid,
nid.nid_name);
#else
error = nfssvc(NFSSVC_IDNAME, &nid);
if (error)
errx(1, "Can't initialize nfs user/groups");
#endif
i = 0;
/*
* Loop around adding all groups.
*/
setgrent();
while (i < nid.nid_usermax && (grp = getgrent())) {
nid.nid_gid = grp->gr_gid;
nid.nid_name = grp->gr_name;
nid.nid_namelen = strlen(grp->gr_name);
nid.nid_flag = NFSID_ADDGID;
#ifdef DEBUG
printf("add gid=%d name=%s\n", nid.nid_gid, nid.nid_name);
#else
error = nfssvc(NFSSVC_IDNAME, &nid);
if (error)
errx(1, "Can't add group %s", grp->gr_name);
#endif
i++;
}
/*
* Loop around adding all users.
*/
start_uidpos = i;
setpwent();
while (i < nid.nid_usermax && (pwd = getpwent())) {
fnd_dup = 0;
/*
* Yes, this is inefficient, but it is only done once when
* the daemon is started and will run in a fraction of a second
* for nid_usermax at 10000. If nid_usermax is cranked up to
* 100000, it will take several seconds, depending on the CPU.
*/
for (j = 0; j < (i - start_uidpos); j++)
if (check_dups[j] == pwd->pw_uid) {
/* Found another entry for uid, so skip it */
fnd_dup = 1;
break;
}
if (fnd_dup != 0)
continue;
check_dups[i - start_uidpos] = pwd->pw_uid;
nid.nid_uid = pwd->pw_uid;
nid.nid_name = pwd->pw_name;
nid.nid_namelen = strlen(pwd->pw_name);
nid.nid_flag = NFSID_ADDUID;
#ifdef DEBUG
printf("add uid=%d name=%s\n", nid.nid_uid, nid.nid_name);
#else
error = nfssvc(NFSSVC_IDNAME, &nid);
if (error)
errx(1, "Can't add user %s", pwd->pw_name);
#endif
i++;
}
/*
* I should feel guilty for not calling this for all the above exit()
* upon error cases, but I don't.
*/
if (mustfreeai)
freeaddrinfo(aip);
#ifdef DEBUG
exit(0);
#endif
/*
* Temporarily block SIGUSR1 and SIGCHLD, so slaves[] can't
* end up bogus.
*/
sigemptyset(&signew);
sigaddset(&signew, SIGUSR1);
sigaddset(&signew, SIGCHLD);
sigprocmask(SIG_BLOCK, &signew, NULL);
daemon(0, 0);
(void)signal(SIGHUP, SIG_IGN);
(void)signal(SIGINT, SIG_IGN);
(void)signal(SIGQUIT, SIG_IGN);
(void)signal(SIGTERM, SIG_IGN);
(void)signal(SIGUSR1, cleanup_term);
(void)signal(SIGCHLD, cleanup_term);
openlog("nfsuserd:", LOG_PID, LOG_DAEMON);
/*
* Fork off the slave daemons that do the work. All the master
* does is kill them off and cleanup.
*/
for (i = 0; i < nfsuserdcnt; i++) {
slaves[i] = fork();
if (slaves[i] == 0) {
im_a_slave = 1;
setproctitle("slave");
sigemptyset(&signew);
sigaddset(&signew, SIGUSR1);
sigprocmask(SIG_UNBLOCK, &signew, NULL);
/*
* and away we go.
*/
svc_run();
syslog(LOG_ERR, "nfsuserd died: %m");
exit(1);
} else if (slaves[i] < 0) {
syslog(LOG_ERR, "fork: %m");
}
}
/*
* Just wait for SIGUSR1 or a child to die and then...
* As the Governor of California would say, "Terminate them".
*/
setproctitle("master");
sigemptyset(&signew);
while (1)
sigsuspend(&signew);
}
/*
* The nfsuserd rpc service
*/
static void
nfsuserdsrv(struct svc_req *rqstp, SVCXPRT *transp)
{
struct passwd *pwd;
struct group *grp;
int error;
u_short sport;
struct info info;
struct nfsd_idargs nid;
u_int32_t saddr;
/*
* Only handle requests from 127.0.0.1 on a reserved port number.
* (Since a reserved port # at localhost implies a client with
* local root, there won't be a security breach. This is about
* the only case I can think of where a reserved port # means
* something.)
*/
sport = ntohs(transp->xp_raddr.sin_port);
saddr = ntohl(transp->xp_raddr.sin_addr.s_addr);
if ((rqstp->rq_proc != NULLPROC && sport >= IPPORT_RESERVED) ||
saddr != 0x7f000001) {
syslog(LOG_ERR, "req from ip=0x%x port=%d\n", saddr, sport);
svcerr_weakauth(transp);
return;
}
switch (rqstp->rq_proc) {
case NULLPROC:
if (!svc_sendreply(transp, (xdrproc_t)xdr_void, NULL))
syslog(LOG_ERR, "Can't send reply");
return;
case RPCNFSUSERD_GETUID:
if (!svc_getargs(transp, (xdrproc_t)xdr_getid,
(caddr_t)&info)) {
svcerr_decode(transp);
return;
}
pwd = getpwuid((uid_t)info.id);
info.retval = 0;
if (pwd != NULL) {
nid.nid_usertimeout = defusertimeout;
nid.nid_uid = pwd->pw_uid;
nid.nid_name = pwd->pw_name;
} else {
nid.nid_usertimeout = 5;
nid.nid_uid = (uid_t)info.id;
nid.nid_name = defaultuser;
}
nid.nid_namelen = strlen(nid.nid_name);
nid.nid_flag = NFSID_ADDUID;
error = nfssvc(NFSSVC_IDNAME, &nid);
if (error) {
info.retval = error;
syslog(LOG_ERR, "Can't add user %s\n", pwd->pw_name);
} else if (verbose) {
syslog(LOG_ERR,"Added uid=%d name=%s\n",
nid.nid_uid, nid.nid_name);
}
if (!svc_sendreply(transp, (xdrproc_t)xdr_retval,
(caddr_t)&info))
syslog(LOG_ERR, "Can't send reply");
return;
case RPCNFSUSERD_GETGID:
if (!svc_getargs(transp, (xdrproc_t)xdr_getid,
(caddr_t)&info)) {
svcerr_decode(transp);
return;
}
grp = getgrgid((gid_t)info.id);
info.retval = 0;
if (grp != NULL) {
nid.nid_usertimeout = defusertimeout;
nid.nid_gid = grp->gr_gid;
nid.nid_name = grp->gr_name;
} else {
nid.nid_usertimeout = 5;
nid.nid_gid = (gid_t)info.id;
nid.nid_name = defaultgroup;
}
nid.nid_namelen = strlen(nid.nid_name);
nid.nid_flag = NFSID_ADDGID;
error = nfssvc(NFSSVC_IDNAME, &nid);
if (error) {
info.retval = error;
syslog(LOG_ERR, "Can't add group %s\n",
grp->gr_name);
} else if (verbose) {
syslog(LOG_ERR,"Added gid=%d name=%s\n",
nid.nid_gid, nid.nid_name);
}
if (!svc_sendreply(transp, (xdrproc_t)xdr_retval,
(caddr_t)&info))
syslog(LOG_ERR, "Can't send reply");
return;
case RPCNFSUSERD_GETUSER:
if (!svc_getargs(transp, (xdrproc_t)xdr_getname,
(caddr_t)&info)) {
svcerr_decode(transp);
return;
}
pwd = getpwnam(info.name);
info.retval = 0;
if (pwd != NULL) {
nid.nid_usertimeout = defusertimeout;
nid.nid_uid = pwd->pw_uid;
nid.nid_name = pwd->pw_name;
} else {
nid.nid_usertimeout = 5;
nid.nid_uid = defaultuid;
nid.nid_name = info.name;
}
nid.nid_namelen = strlen(nid.nid_name);
nid.nid_flag = NFSID_ADDUSERNAME;
error = nfssvc(NFSSVC_IDNAME, &nid);
if (error) {
info.retval = error;
syslog(LOG_ERR, "Can't add user %s\n", pwd->pw_name);
} else if (verbose) {
syslog(LOG_ERR,"Added uid=%d name=%s\n",
nid.nid_uid, nid.nid_name);
}
if (!svc_sendreply(transp, (xdrproc_t)xdr_retval,
(caddr_t)&info))
syslog(LOG_ERR, "Can't send reply");
return;
case RPCNFSUSERD_GETGROUP:
if (!svc_getargs(transp, (xdrproc_t)xdr_getname,
(caddr_t)&info)) {
svcerr_decode(transp);
return;
}
grp = getgrnam(info.name);
info.retval = 0;
if (grp != NULL) {
nid.nid_usertimeout = defusertimeout;
nid.nid_gid = grp->gr_gid;
nid.nid_name = grp->gr_name;
} else {
nid.nid_usertimeout = 5;
nid.nid_gid = defaultgid;
nid.nid_name = info.name;
}
nid.nid_namelen = strlen(nid.nid_name);
nid.nid_flag = NFSID_ADDGROUPNAME;
error = nfssvc(NFSSVC_IDNAME, &nid);
if (error) {
info.retval = error;
syslog(LOG_ERR, "Can't add group %s\n",
grp->gr_name);
} else if (verbose) {
syslog(LOG_ERR,"Added gid=%d name=%s\n",
nid.nid_gid, nid.nid_name);
}
if (!svc_sendreply(transp, (xdrproc_t)xdr_retval,
(caddr_t)&info))
syslog(LOG_ERR, "Can't send reply");
return;
default:
svcerr_noproc(transp);
return;
};
}
/*
* Xdr routine to get an id number
*/
static bool_t
xdr_getid(XDR *xdrsp, caddr_t cp)
{
struct info *ifp = (struct info *)cp;
return (xdr_long(xdrsp, &ifp->id));
}
/*
* Xdr routine to get a user name
*/
static bool_t
xdr_getname(XDR *xdrsp, caddr_t cp)
{
struct info *ifp = (struct info *)cp;
long len;
if (!xdr_long(xdrsp, &len))
return (0);
if (len > MAXNAME)
return (0);
if (!xdr_opaque(xdrsp, ifp->name, len))
return (0);
ifp->name[len] = '\0';
return (1);
}
/*
* Xdr routine to return the value.
*/
static bool_t
xdr_retval(XDR *xdrsp, caddr_t cp)
{
struct info *ifp = (struct info *)cp;
long val;
val = ifp->retval;
return (xdr_long(xdrsp, &val));
}
/*
* cleanup_term() called via SIGUSR1.
*/
static void
cleanup_term(int signo __unused)
{
int i, cnt;
if (im_a_slave)
exit(0);
/*
* Ok, so I'm the master.
* As the Governor of California might say, "Terminate them".
*/
cnt = 0;
for (i = 0; i < nfsuserdcnt; i++) {
if (slaves[i] != (pid_t)-1) {
cnt++;
kill(slaves[i], SIGUSR1);
}
}
/*
* and wait for them to die
*/
for (i = 0; i < cnt; i++)
wait3(NULL, 0, NULL);
/*
* Finally, get rid of the socket
*/
if (nfssvc(NFSSVC_NFSUSERDDELPORT, NULL) < 0) {
syslog(LOG_ERR, "Can't do nfssvc() to delete the port\n");
exit(1);
}
exit(0);
}
static void
usage(void)
{
errx(1,
"usage: nfsuserd [-usermax cache_size] [-usertimeout minutes] [-verbose] [-domain domain_name] [n]");
}