freebsd-skq/sys/nfsserver/nfs_syscalls.c
sam 3eac15aaa3 Assert GIANT_REQUIRED where sockets are manipulated. This is
preparatory for MPSAFE network commits and ongoing socket
locking work.

Supported by:	FreeBSD Foundation
2003-11-07 22:57:09 +00:00

688 lines
17 KiB
C

/*
* Copyright (c) 1989, 1993
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*
* @(#)nfs_syscalls.c 8.5 (Berkeley) 3/30/95
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet6.h"
#include "opt_mac.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sysproto.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/file.h>
#include <sys/filedesc.h>
#include <sys/vnode.h>
#include <sys/mac.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/proc.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/namei.h>
#include <sys/fcntl.h>
#include <sys/lockf.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#ifdef INET6
#include <net/if.h>
#include <netinet6/in6_var.h>
#endif
#include <nfs/xdr_subs.h>
#include <nfs/rpcv2.h>
#include <nfs/nfsproto.h>
#include <nfsserver/nfs.h>
#include <nfsserver/nfsm_subs.h>
#include <nfsserver/nfsrvcache.h>
static MALLOC_DEFINE(M_NFSSVC, "NFS srvsock", "Nfs server structure");
MALLOC_DEFINE(M_NFSRVDESC, "NFSV3 srvdesc", "NFS server socket descriptor");
MALLOC_DEFINE(M_NFSD, "NFS daemon", "Nfs server daemon structure");
#define TRUE 1
#define FALSE 0
SYSCTL_DECL(_vfs_nfsrv);
int nfsd_waiting = 0;
static int nfs_numnfsd = 0;
static int notstarted = 1;
static int nfs_privport = 0;
SYSCTL_INT(_vfs_nfsrv, NFS_NFSPRIVPORT, nfs_privport, CTLFLAG_RW,
&nfs_privport, 0, "");
SYSCTL_INT(_vfs_nfsrv, OID_AUTO, gatherdelay, CTLFLAG_RW,
&nfsrvw_procrastinate, 0, "");
SYSCTL_INT(_vfs_nfsrv, OID_AUTO, gatherdelay_v3, CTLFLAG_RW,
&nfsrvw_procrastinate_v3, 0, "");
static int nfssvc_addsock(struct file *, struct sockaddr *,
struct thread *);
static void nfsrv_zapsock(struct nfssvc_sock *slp);
static int nfssvc_nfsd(struct thread *);
/*
* NFS server system calls
*/
/*
* Nfs server psuedo system call for the nfsd's
* Based on the flag value it either:
* - adds a socket to the selection list
* - remains in the kernel as an nfsd
* - remains in the kernel as an nfsiod
* For INET6 we suppose that nfsd provides only IN6P_IPV6_V6ONLY sockets
* and that mountd provides
* - sockaddr with no IPv4-mapped addresses
* - mask for both INET and INET6 families if there is IPv4-mapped overlap
*/
#ifndef _SYS_SYSPROTO_H_
struct nfssvc_args {
int flag;
caddr_t argp;
};
#endif
/*
* MPSAFE
*/
int
nfssvc(struct thread *td, struct nfssvc_args *uap)
{
struct file *fp;
struct sockaddr *nam;
struct nfsd_args nfsdarg;
int error;
#ifdef MAC
error = mac_check_system_nfsd(td->td_ucred);
if (error)
return (error);
#endif
error = suser(td);
if (error)
return (error);
mtx_lock(&Giant);
while (nfssvc_sockhead_flag & SLP_INIT) {
nfssvc_sockhead_flag |= SLP_WANTINIT;
(void) tsleep(&nfssvc_sockhead, PSOCK, "nfsd init", 0);
}
if (uap->flag & NFSSVC_ADDSOCK) {
error = copyin(uap->argp, (caddr_t)&nfsdarg, sizeof(nfsdarg));
if (error)
goto done2;
if ((error = fget(td, nfsdarg.sock, &fp)) != 0)
goto done2;
if (fp->f_type != DTYPE_SOCKET) {
fdrop(fp, td);
goto done2;
}
/*
* Get the client address for connected sockets.
*/
if (nfsdarg.name == NULL || nfsdarg.namelen == 0)
nam = NULL;
else {
error = getsockaddr(&nam, nfsdarg.name,
nfsdarg.namelen);
if (error) {
fdrop(fp, td);
goto done2;
}
}
error = nfssvc_addsock(fp, nam, td);
fdrop(fp, td);
} else if (uap->flag & NFSSVC_NFSD) {
error = nfssvc_nfsd(td);
} else {
error = ENXIO;
}
if (error == EINTR || error == ERESTART)
error = 0;
done2:
mtx_unlock(&Giant);
return (error);
}
/*
* Adds a socket to the list for servicing by nfsds.
*/
static int
nfssvc_addsock(struct file *fp, struct sockaddr *mynam, struct thread *td)
{
int siz;
struct nfssvc_sock *slp;
struct socket *so;
int error, s;
GIANT_REQUIRED; /* XXX until socket locking done */
so = fp->f_data;
#if 0
tslp = NULL;
/*
* Add it to the list, as required.
*/
if (so->so_proto->pr_protocol == IPPROTO_UDP) {
tslp = nfs_udpsock;
if (tslp->ns_flag & SLP_VALID) {
if (mynam != NULL)
FREE(mynam, M_SONAME);
return (EPERM);
}
}
#endif
if (so->so_type == SOCK_STREAM)
siz = NFS_MAXPACKET + sizeof (u_long);
else
siz = NFS_MAXPACKET;
error = soreserve(so, siz, siz);
if (error) {
if (mynam != NULL)
FREE(mynam, M_SONAME);
return (error);
}
/*
* Set protocol specific options { for now TCP only } and
* reserve some space. For datagram sockets, this can get called
* repeatedly for the same socket, but that isn't harmful.
*/
if (so->so_type == SOCK_STREAM) {
struct sockopt sopt;
int val;
bzero(&sopt, sizeof sopt);
sopt.sopt_dir = SOPT_SET;
sopt.sopt_level = SOL_SOCKET;
sopt.sopt_name = SO_KEEPALIVE;
sopt.sopt_val = &val;
sopt.sopt_valsize = sizeof val;
val = 1;
sosetopt(so, &sopt);
}
if (so->so_proto->pr_protocol == IPPROTO_TCP) {
struct sockopt sopt;
int val;
bzero(&sopt, sizeof sopt);
sopt.sopt_dir = SOPT_SET;
sopt.sopt_level = IPPROTO_TCP;
sopt.sopt_name = TCP_NODELAY;
sopt.sopt_val = &val;
sopt.sopt_valsize = sizeof val;
val = 1;
sosetopt(so, &sopt);
}
so->so_rcv.sb_flags &= ~SB_NOINTR;
so->so_rcv.sb_timeo = 0;
so->so_snd.sb_flags &= ~SB_NOINTR;
so->so_snd.sb_timeo = 0;
slp = (struct nfssvc_sock *)
malloc(sizeof (struct nfssvc_sock), M_NFSSVC,
M_WAITOK | M_ZERO);
STAILQ_INIT(&slp->ns_rec);
TAILQ_INSERT_TAIL(&nfssvc_sockhead, slp, ns_chain);
slp->ns_so = so;
slp->ns_nam = mynam;
fhold(fp);
slp->ns_fp = fp;
s = splnet();
so->so_upcallarg = (caddr_t)slp;
so->so_upcall = nfsrv_rcv;
so->so_rcv.sb_flags |= SB_UPCALL;
slp->ns_flag = (SLP_VALID | SLP_NEEDQ);
nfsrv_wakenfsd(slp);
splx(s);
return (0);
}
/*
* Called by nfssvc() for nfsds. Just loops around servicing rpc requests
* until it is killed by a signal.
*/
static int
nfssvc_nfsd(struct thread *td)
{
int siz;
struct nfssvc_sock *slp;
struct nfsd *nfsd;
struct nfsrv_descript *nd = NULL;
struct mbuf *m, *mreq;
int error = 0, cacherep, s, sotype, writes_todo;
int procrastinate;
u_quad_t cur_usec;
#ifndef nolint
cacherep = RC_DOIT;
writes_todo = 0;
#endif
nfsd = (struct nfsd *)
malloc(sizeof (struct nfsd), M_NFSD, M_WAITOK | M_ZERO);
s = splnet();
nfsd->nfsd_td = td;
TAILQ_INSERT_TAIL(&nfsd_head, nfsd, nfsd_chain);
nfs_numnfsd++;
/*
* Loop getting rpc requests until SIGKILL.
*/
for (;;) {
if ((nfsd->nfsd_flag & NFSD_REQINPROG) == 0) {
while (nfsd->nfsd_slp == NULL &&
(nfsd_head_flag & NFSD_CHECKSLP) == 0) {
nfsd->nfsd_flag |= NFSD_WAITING;
nfsd_waiting++;
error = tsleep(nfsd, PSOCK | PCATCH,
"-", 0);
nfsd_waiting--;
if (error)
goto done;
}
if (nfsd->nfsd_slp == NULL &&
(nfsd_head_flag & NFSD_CHECKSLP) != 0) {
TAILQ_FOREACH(slp, &nfssvc_sockhead, ns_chain) {
if ((slp->ns_flag & (SLP_VALID | SLP_DOREC))
== (SLP_VALID | SLP_DOREC)) {
slp->ns_flag &= ~SLP_DOREC;
slp->ns_sref++;
nfsd->nfsd_slp = slp;
break;
}
}
if (slp == 0)
nfsd_head_flag &= ~NFSD_CHECKSLP;
}
if ((slp = nfsd->nfsd_slp) == NULL)
continue;
if (slp->ns_flag & SLP_VALID) {
if (slp->ns_flag & SLP_DISCONN)
nfsrv_zapsock(slp);
else if (slp->ns_flag & SLP_NEEDQ) {
slp->ns_flag &= ~SLP_NEEDQ;
(void) nfs_slplock(slp, 1);
nfsrv_rcv(slp->ns_so, (caddr_t)slp,
M_TRYWAIT);
nfs_slpunlock(slp);
}
error = nfsrv_dorec(slp, nfsd, &nd);
cur_usec = nfs_curusec();
if (error && LIST_FIRST(&slp->ns_tq) &&
LIST_FIRST(&slp->ns_tq)->nd_time <= cur_usec) {
error = 0;
cacherep = RC_DOIT;
writes_todo = 1;
} else
writes_todo = 0;
nfsd->nfsd_flag |= NFSD_REQINPROG;
}
} else {
error = 0;
slp = nfsd->nfsd_slp;
}
if (error || (slp->ns_flag & SLP_VALID) == 0) {
if (nd) {
free((caddr_t)nd, M_NFSRVDESC);
nd = NULL;
}
nfsd->nfsd_slp = NULL;
nfsd->nfsd_flag &= ~NFSD_REQINPROG;
nfsrv_slpderef(slp);
continue;
}
splx(s);
sotype = slp->ns_so->so_type;
if (nd) {
getmicrotime(&nd->nd_starttime);
if (nd->nd_nam2)
nd->nd_nam = nd->nd_nam2;
else
nd->nd_nam = slp->ns_nam;
/*
* Check to see if authorization is needed.
*/
cacherep = nfsrv_getcache(nd, &mreq);
if (nfs_privport) {
/* Check if source port is privileged */
u_short port;
struct sockaddr *nam = nd->nd_nam;
struct sockaddr_in *sin;
sin = (struct sockaddr_in *)nam;
/*
* INET/INET6 - same code:
* sin_port and sin6_port are at same offset
*/
port = ntohs(sin->sin_port);
if (port >= IPPORT_RESERVED &&
nd->nd_procnum != NFSPROC_NULL) {
#if defined(INET6) && defined(KLD_MODULE)
/* do not use ip6_sprintf: the nfs module should work without INET6 */
char b6[INET6_ADDRSTRLEN];
#define ip6_sprintf(a) \
(sprintf(b6, "%x:%x:%x:%x:%x:%x:%x:%x", \
(a)->s6_addr16[0], (a)->s6_addr16[1], \
(a)->s6_addr16[2], (a)->s6_addr16[3], \
(a)->s6_addr16[4], (a)->s6_addr16[5], \
(a)->s6_addr16[6], (a)->s6_addr16[7]), \
b6)
#endif
nd->nd_procnum = NFSPROC_NOOP;
nd->nd_repstat = (NFSERR_AUTHERR | AUTH_TOOWEAK);
cacherep = RC_DOIT;
printf("NFS request from unprivileged port (%s:%d)\n",
#ifdef INET6
sin->sin_family == AF_INET6 ?
ip6_sprintf(&satosin6(sin)->sin6_addr) :
#undef ip6_sprintf
#endif
inet_ntoa(sin->sin_addr), port);
}
}
}
/*
* Loop to get all the write rpc relies that have been
* gathered together.
*/
do {
switch (cacherep) {
case RC_DOIT:
if (nd && (nd->nd_flag & ND_NFSV3))
procrastinate = nfsrvw_procrastinate_v3;
else
procrastinate = nfsrvw_procrastinate;
if (writes_todo || (nd->nd_procnum == NFSPROC_WRITE &&
procrastinate > 0 && !notstarted))
error = nfsrv_writegather(&nd, slp,
nfsd->nfsd_td, &mreq);
else
error = (*(nfsrv3_procs[nd->nd_procnum]))(nd,
slp, nfsd->nfsd_td, &mreq);
if (mreq == NULL)
break;
if (error != 0 && error != NFSERR_RETVOID) {
nfsrvstats.srv_errs++;
nfsrv_updatecache(nd, FALSE, mreq);
if (nd->nd_nam2)
FREE(nd->nd_nam2, M_SONAME);
break;
}
nfsrvstats.srvrpccnt[nd->nd_procnum]++;
nfsrv_updatecache(nd, TRUE, mreq);
nd->nd_mrep = NULL;
/* FALLTHROUGH */
case RC_REPLY:
siz = m_length(mreq, NULL);
if (siz <= 0 || siz > NFS_MAXPACKET) {
printf("mbuf siz=%d\n",siz);
panic("Bad nfs svc reply");
}
m = mreq;
m->m_pkthdr.len = siz;
m->m_pkthdr.rcvif = NULL;
/*
* For stream protocols, prepend a Sun RPC
* Record Mark.
*/
if (sotype == SOCK_STREAM) {
M_PREPEND(m, NFSX_UNSIGNED, M_TRYWAIT);
*mtod(m, u_int32_t *) = htonl(0x80000000 | siz);
}
if (slp->ns_so->so_proto->pr_flags & PR_CONNREQUIRED)
(void) nfs_slplock(slp, 1);
if (slp->ns_flag & SLP_VALID)
error = nfsrv_send(slp->ns_so, nd->nd_nam2, m);
else {
error = EPIPE;
m_freem(m);
}
if (nd->nd_nam2)
FREE(nd->nd_nam2, M_SONAME);
if (nd->nd_mrep)
m_freem(nd->nd_mrep);
if (error == EPIPE)
nfsrv_zapsock(slp);
if (slp->ns_so->so_proto->pr_flags & PR_CONNREQUIRED)
nfs_slpunlock(slp);
if (error == EINTR || error == ERESTART) {
free((caddr_t)nd, M_NFSRVDESC);
nfsrv_slpderef(slp);
s = splnet();
goto done;
}
break;
case RC_DROPIT:
m_freem(nd->nd_mrep);
if (nd->nd_nam2)
FREE(nd->nd_nam2, M_SONAME);
break;
};
if (nd) {
FREE((caddr_t)nd, M_NFSRVDESC);
nd = NULL;
}
/*
* Check to see if there are outstanding writes that
* need to be serviced.
*/
cur_usec = nfs_curusec();
s = splsoftclock();
if (LIST_FIRST(&slp->ns_tq) &&
LIST_FIRST(&slp->ns_tq)->nd_time <= cur_usec) {
cacherep = RC_DOIT;
writes_todo = 1;
} else
writes_todo = 0;
splx(s);
} while (writes_todo);
s = splnet();
if (nfsrv_dorec(slp, nfsd, &nd)) {
nfsd->nfsd_flag &= ~NFSD_REQINPROG;
nfsd->nfsd_slp = NULL;
nfsrv_slpderef(slp);
}
}
done:
TAILQ_REMOVE(&nfsd_head, nfsd, nfsd_chain);
splx(s);
free((caddr_t)nfsd, M_NFSD);
if (--nfs_numnfsd == 0)
nfsrv_init(TRUE); /* Reinitialize everything */
return (error);
}
/*
* Shut down a socket associated with an nfssvc_sock structure.
* Should be called with the send lock set, if required.
* The trick here is to increment the sref at the start, so that the nfsds
* will stop using it and clear ns_flag at the end so that it will not be
* reassigned during cleanup.
*/
static void
nfsrv_zapsock(struct nfssvc_sock *slp)
{
struct nfsrv_descript *nwp, *nnwp;
struct socket *so;
struct file *fp;
struct nfsrv_rec *rec;
int s;
slp->ns_flag &= ~SLP_ALLFLAGS;
fp = slp->ns_fp;
if (fp) {
slp->ns_fp = NULL;
so = slp->ns_so;
so->so_rcv.sb_flags &= ~SB_UPCALL;
so->so_upcall = NULL;
so->so_upcallarg = NULL;
soshutdown(so, 2);
closef(fp, NULL);
if (slp->ns_nam)
FREE(slp->ns_nam, M_SONAME);
m_freem(slp->ns_raw);
while ((rec = STAILQ_FIRST(&slp->ns_rec)) != NULL) {
STAILQ_REMOVE_HEAD(&slp->ns_rec, nr_link);
if (rec->nr_address)
FREE(rec->nr_address, M_SONAME);
m_freem(rec->nr_packet);
free(rec, M_NFSRVDESC);
}
s = splsoftclock();
for (nwp = LIST_FIRST(&slp->ns_tq); nwp; nwp = nnwp) {
nnwp = LIST_NEXT(nwp, nd_tq);
LIST_REMOVE(nwp, nd_tq);
free((caddr_t)nwp, M_NFSRVDESC);
}
LIST_INIT(&slp->ns_tq);
splx(s);
}
}
/*
* Derefence a server socket structure. If it has no more references and
* is no longer valid, you can throw it away.
*/
void
nfsrv_slpderef(struct nfssvc_sock *slp)
{
if (--(slp->ns_sref) == 0 && (slp->ns_flag & SLP_VALID) == 0) {
TAILQ_REMOVE(&nfssvc_sockhead, slp, ns_chain);
free((caddr_t)slp, M_NFSSVC);
}
}
/*
* Lock a socket against others.
*/
int
nfs_slplock(struct nfssvc_sock *slp, int wait)
{
int *statep = &slp->ns_solock;
if (!wait && (*statep & NFSRV_SNDLOCK))
return(0); /* already locked, fail */
while (*statep & NFSRV_SNDLOCK) {
*statep |= NFSRV_WANTSND;
(void) tsleep(statep, PZERO - 1, "nfsslplck", 0);
}
*statep |= NFSRV_SNDLOCK;
return (1);
}
/*
* Unlock the stream socket for others.
*/
void
nfs_slpunlock(struct nfssvc_sock *slp)
{
int *statep = &slp->ns_solock;
if ((*statep & NFSRV_SNDLOCK) == 0)
panic("nfs slpunlock");
*statep &= ~NFSRV_SNDLOCK;
if (*statep & NFSRV_WANTSND) {
*statep &= ~NFSRV_WANTSND;
wakeup(statep);
}
}
/*
* Initialize the data structures for the server.
* Handshake with any new nfsds starting up to avoid any chance of
* corruption.
*/
void
nfsrv_init(int terminating)
{
struct nfssvc_sock *slp, *nslp;
if (nfssvc_sockhead_flag & SLP_INIT)
panic("nfsd init");
nfssvc_sockhead_flag |= SLP_INIT;
if (terminating) {
for (slp = TAILQ_FIRST(&nfssvc_sockhead); slp != 0; slp = nslp){
nslp = TAILQ_NEXT(slp, ns_chain);
if (slp->ns_flag & SLP_VALID)
nfsrv_zapsock(slp);
TAILQ_REMOVE(&nfssvc_sockhead, slp, ns_chain);
free((caddr_t)slp, M_NFSSVC);
}
nfsrv_cleancache(); /* And clear out server cache */
} else
nfs_pub.np_valid = 0;
TAILQ_INIT(&nfssvc_sockhead);
nfssvc_sockhead_flag &= ~SLP_INIT;
if (nfssvc_sockhead_flag & SLP_WANTINIT) {
nfssvc_sockhead_flag &= ~SLP_WANTINIT;
wakeup(&nfssvc_sockhead);
}
TAILQ_INIT(&nfsd_head);
nfsd_head_flag &= ~NFSD_CHECKSLP;
#if 0
nfs_udpsock = (struct nfssvc_sock *)
malloc(sizeof (struct nfssvc_sock), M_NFSSVC, M_WAITOK | M_ZERO);
STAILQ_INIT(&nfs_udpsock->ns_rec);
TAILQ_INSERT_HEAD(&nfssvc_sockhead, nfs_udpsock, ns_chain);
nfs_cltpsock = (struct nfssvc_sock *)
malloc(sizeof (struct nfssvc_sock), M_NFSSVC, M_WAITOK | M_ZERO);
STAILQ_INIT(&nfs_cltpsock->ns_rec);
TAILQ_INSERT_TAIL(&nfssvc_sockhead, nfs_cltpsock, ns_chain);
#endif
}