4.3BSD-Reno/src/sys/nfs/nfs_socket.c
/*
* Copyright (c) 1989 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 is only permitted until one year after the first shipment
* of 4.4BSD by the Regents. Otherwise, redistribution and use in source and
* binary forms are permitted provided that: (1) source distributions retain
* this entire copyright notice and comment, and (2) distributions including
* binaries display the following acknowledgement: This product includes
* software developed by the University of California, Berkeley and its
* contributors'' in the documentation or other materials provided with the
* distribution and in all advertising materials mentioning features or use
* of this software. 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 AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
* @(#)nfs_socket.c 7.18 (Berkeley) 6/28/90
*/
/*
* Socket operations for use by nfs
*/
#include "types.h"
#include "param.h"
#include "uio.h"
#include "user.h"
#include "proc.h"
#include "signal.h"
#include "mount.h"
#include "kernel.h"
#include "malloc.h"
#include "mbuf.h"
#include "vnode.h"
#include "domain.h"
#include "protosw.h"
#include "socket.h"
#include "socketvar.h"
#include "../netinet/in.h"
#include "../netinet/tcp.h"
#include "rpcv2.h"
#include "nfsv2.h"
#include "nfs.h"
#include "xdr_subs.h"
#include "nfsm_subs.h"
#include "nfsmount.h"
#include "syslog.h"
#define TRUE 1
#define FALSE 0
/*
* External data, mostly RPC constants in XDR form
*/
extern u_long rpc_reply, rpc_msgdenied, rpc_mismatch, rpc_vers, rpc_auth_unix,
rpc_msgaccepted, rpc_call;
extern u_long nfs_prog, nfs_vers;
/* Maybe these should be bits in a u_long ?? */
extern int nonidempotent[NFS_NPROCS];
int nfs_sbwait();
void nfs_disconnect();
int nfsrv_null(),
nfsrv_getattr(),
nfsrv_setattr(),
nfsrv_lookup(),
nfsrv_readlink(),
nfsrv_read(),
nfsrv_write(),
nfsrv_create(),
nfsrv_remove(),
nfsrv_rename(),
nfsrv_link(),
nfsrv_symlink(),
nfsrv_mkdir(),
nfsrv_rmdir(),
nfsrv_readdir(),
nfsrv_statfs(),
nfsrv_noop();
int (*nfsrv_procs[NFS_NPROCS])() = {
nfsrv_null,
nfsrv_getattr,
nfsrv_setattr,
nfsrv_noop,
nfsrv_lookup,
nfsrv_readlink,
nfsrv_read,
nfsrv_noop,
nfsrv_write,
nfsrv_create,
nfsrv_remove,
nfsrv_rename,
nfsrv_link,
nfsrv_symlink,
nfsrv_mkdir,
nfsrv_rmdir,
nfsrv_readdir,
nfsrv_statfs,
};
struct nfsreq nfsreqh;
int nfsrexmtthresh = NFS_FISHY;
int nfs_tcpnodelay = 1;
/*
* Initialize sockets and congestion for a new NFS connection.
* We do not free the sockaddr if error.
*/
nfs_connect(nmp)
register struct nfsmount *nmp;
{
register struct socket *so;
int s, error;
struct mbuf *m;
nmp->nm_so = (struct socket *)0;
if (error = socreate(mtod(nmp->nm_nam, struct sockaddr *)->sa_family,
&nmp->nm_so, nmp->nm_sotype, nmp->nm_soproto))
goto bad;
so = nmp->nm_so;
nmp->nm_soflags = so->so_proto->pr_flags;
/*
* Protocols that do not require connections may be optionally left
* unconnected for servers that reply from a port other than NFS_PORT.
*/
if (nmp->nm_flag & NFSMNT_NOCONN) {
if (nmp->nm_soflags & PR_CONNREQUIRED) {
error = ENOTCONN;
goto bad;
}
} else {
if (error = soconnect(so, nmp->nm_nam))
goto bad;
/*
* Wait for the connection to complete. Cribbed from the
* connect system call but with the wait at negative prio.
*/
s = splnet();
while ((so->so_state & SS_ISCONNECTING) && so->so_error == 0)
(void) tsleep((caddr_t)&so->so_timeo, PSOCK, "nfscon", 0);
splx(s);
if (so->so_error) {
error = so->so_error;
goto bad;
}
}
if (nmp->nm_sotype == SOCK_DGRAM) {
if (nmp->nm_flag & (NFSMNT_SOFT | NFSMNT_SPONGY | NFSMNT_INT)) {
so->so_rcv.sb_timeo = (5 * hz);
so->so_snd.sb_timeo = (5 * hz);
} else {
so->so_rcv.sb_timeo = 0;
so->so_snd.sb_timeo = 0;
}
if (error = soreserve(so, nmp->nm_wsize + NFS_MAXPKTHDR,
nmp->nm_rsize + NFS_MAXPKTHDR))
goto bad;
} else {
if (nmp->nm_flag & (NFSMNT_SOFT | NFSMNT_SPONGY | NFSMNT_INT)) {
so->so_rcv.sb_timeo = (5 * hz);
so->so_snd.sb_timeo = (5 * hz);
} else {
so->so_rcv.sb_timeo = 0;
so->so_snd.sb_timeo = 0;
}
if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
MGET(m, M_WAIT, MT_SOOPTS);
*mtod(m, int *) = 1;
m->m_len = sizeof(int);
sosetopt(so, SOL_SOCKET, SO_KEEPALIVE, m);
}
if (so->so_proto->pr_domain->dom_family == AF_INET &&
so->so_proto->pr_protocol == IPPROTO_TCP &&
nfs_tcpnodelay) {
MGET(m, M_WAIT, MT_SOOPTS);
*mtod(m, int *) = 1;
m->m_len = sizeof(int);
sosetopt(so, IPPROTO_TCP, TCP_NODELAY, m);
}
if (error = soreserve(so,
nmp->nm_wsize + NFS_MAXPKTHDR + sizeof(u_long),
nmp->nm_rsize + NFS_MAXPKTHDR + sizeof(u_long)))
goto bad;
}
so->so_rcv.sb_flags |= SB_NOINTR;
so->so_snd.sb_flags |= SB_NOINTR;
/* Initialize other non-zero congestion variables */
nmp->nm_rto = NFS_TIMEO;
nmp->nm_window = 2; /* Initial send window */
nmp->nm_ssthresh = NFS_MAXWINDOW; /* Slowstart threshold */
nmp->nm_rttvar = nmp->nm_rto << 1;
nmp->nm_sent = 0;
nmp->nm_currexmit = 0;
return (0);
bad:
nfs_disconnect(nmp);
return (error);
}
/*
* Reconnect routine:
* Called when a connection is broken on a reliable protocol.
* - clean up the old socket
* - nfs_connect() again
* - set R_MUSTRESEND for all outstanding requests on mount point
* If this fails the mount point is DEAD!
* nb: Must be called with the nfs_solock() set on the mount point.
*/
nfs_reconnect(rep, nmp)
register struct nfsreq *rep;
register struct nfsmount *nmp;
{
register struct nfsreq *rp;
int error;
if (rep->r_procp)
tprintf(rep->r_procp->p_session,
"Nfs server %s, trying reconnect\n",
nmp->nm_mountp->mnt_stat.f_mntfromname);
else
tprintf(NULL, "Nfs server %s, trying a reconnect\n",
nmp->nm_mountp->mnt_stat.f_mntfromname);
while (error = nfs_connect(nmp)) {
#ifdef lint
error = error;
#endif /* lint */
if ((nmp->nm_flag & NFSMNT_INT) && nfs_sigintr(rep->r_procp))
return (EINTR);
(void) tsleep((caddr_t)&lbolt, PSOCK, "nfscon", 0);
}
if (rep->r_procp)
tprintf(rep->r_procp->p_session,
"Nfs server %s, reconnected\n",
nmp->nm_mountp->mnt_stat.f_mntfromname);
else
tprintf(NULL, "Nfs server %s, reconnected\n",
nmp->nm_mountp->mnt_stat.f_mntfromname);
/*
* Loop through outstanding request list and fix up all requests
* on old socket.
*/
rp = nfsreqh.r_next;
while (rp != &nfsreqh) {
if (rp->r_nmp == nmp)
rp->r_flags |= R_MUSTRESEND;
rp = rp->r_next;
}
return (0);
}
/*
* NFS disconnect. Clean up and unlink.
*/
void
nfs_disconnect(nmp)
register struct nfsmount *nmp;
{
register struct socket *so;
if (nmp->nm_so) {
so = nmp->nm_so;
nmp->nm_so = (struct socket *)0;
soshutdown(so, 2);
soclose(so);
}
}
/*
* This is the nfs send routine. For connection based socket types, it
* must be called with an nfs_solock() on the socket.
* "rep == NULL" indicates that it has been called from a server.
*/
nfs_send(so, nam, top, rep)
register struct socket *so;
struct mbuf *nam;
register struct mbuf *top;
struct nfsreq *rep;
{
struct mbuf *sendnam;
int error, soflags;
if (rep) {
if (rep->r_flags & R_SOFTTERM) {
m_freem(top);
return (EINTR);
}
if (rep->r_nmp->nm_so == NULL &&
(error = nfs_reconnect(rep, rep->r_nmp)))
return (error);
rep->r_flags &= ~R_MUSTRESEND;
so = rep->r_nmp->nm_so;
soflags = rep->r_nmp->nm_soflags;
} else
soflags = so->so_proto->pr_flags;
if ((soflags & PR_CONNREQUIRED) || (so->so_state & SS_ISCONNECTED))
sendnam = (struct mbuf *)0;
else
sendnam = nam;
error = sosend(so, sendnam, (struct uio *)0, top,
(struct mbuf *)0, 0);
if (error == EWOULDBLOCK && rep) {
if (rep->r_flags & R_SOFTTERM)
error = EINTR;
else {
rep->r_flags |= R_MUSTRESEND;
error = 0;
}
}
/*
* Ignore socket errors??
*/
if (error && error != EINTR && error != ERESTART)
error = 0;
return (error);
}
/*
* Receive a Sun RPC Request/Reply. For SOCK_DGRAM, the work is all
* done by soreceive(), but for SOCK_STREAM we must deal with the Record
* Mark and consolidate the data into a new mbuf list.
* nb: Sometimes TCP passes the data up to soreceive() in long lists of
* small mbufs.
* For SOCK_STREAM we must be very careful to read an entire record once
* we have read any of it, even if the system call has been interrupted.
*/
nfs_receive(so, aname, mp, rep)
register struct socket *so;
struct mbuf **aname;
struct mbuf **mp;
register struct nfsreq *rep;
{
struct uio auio;
struct iovec aio;
register struct mbuf *m;
struct mbuf *m2, *m3, *mnew, **mbp;
caddr_t fcp, tcp;
u_long len;
struct mbuf **getnam;
int error, siz, mlen, soflags, rcvflg = MSG_WAITALL;
/*
* Set up arguments for soreceive()
*/
*mp = (struct mbuf *)0;
*aname = (struct mbuf *)0;
if (rep)
soflags = rep->r_nmp->nm_soflags;
else
soflags = so->so_proto->pr_flags;
/*
* For reliable protocols, lock against other senders/receivers
* in case a reconnect is necessary.
* For SOCK_STREAM, first get the Record Mark to find out how much
* more there is to get.
* We must lock the socket against other receivers
* until we have an entire rpc request/reply.
*/
if (soflags & PR_CONNREQUIRED) {
tryagain:
/*
* Check for fatal errors and resending request.
*/
if (rep) {
/*
* Ugh: If a reconnect attempt just happened, nm_so
* would have changed. NULL indicates a failed
* attempt that has essentially shut down this
* mount point.
*/
if (rep->r_mrep || (so = rep->r_nmp->nm_so) == NULL ||
(rep->r_flags & R_SOFTTERM))
return (EINTR);
while (rep->r_flags & R_MUSTRESEND) {
m = m_copym(rep->r_mreq, 0, M_COPYALL, M_WAIT);
nfsstats.rpcretries++;
if (error = nfs_send(so, rep->r_nmp->nm_nam, m,
rep))
goto errout;
}
}
if ((soflags & PR_ATOMIC) == 0) {
aio.iov_base = (caddr_t) &len;
aio.iov_len = sizeof(u_long);
auio.uio_iov = &aio;
auio.uio_iovcnt = 1;
auio.uio_segflg = UIO_SYSSPACE;
auio.uio_rw = UIO_READ;
auio.uio_offset = 0;
auio.uio_resid = sizeof(u_long);
do {
error = soreceive(so, (struct mbuf **)0, &auio,
(struct mbuf **)0, (struct mbuf **)0, &rcvflg);
if (error == EWOULDBLOCK && rep) {
if (rep->r_flags & R_SOFTTERM)
return (EINTR);
if (rep->r_flags & R_MUSTRESEND)
goto tryagain;
}
} while (error == EWOULDBLOCK);
if (!error && auio.uio_resid > 0)
error = EPIPE;
if (error)
goto errout;
len = ntohl(len) & ~0x80000000;
/*
* This is SERIOUS! We are out of sync with the sender
* and forcing a disconnect/reconnect is all I can do.
*/
if (len > NFS_MAXPACKET) {
error = EFBIG;
goto errout;
}
auio.uio_resid = len;
do {
error = soreceive(so, (struct mbuf **)0,
&auio, mp, (struct mbuf **)0, &rcvflg);
} while (error == EWOULDBLOCK || error == EINTR ||
error == ERESTART);
if (!error && auio.uio_resid > 0)
error = EPIPE;
} else {
auio.uio_resid = len = 1000000; /* Anything Big */
do {
error = soreceive(so, (struct mbuf **)0,
&auio, mp, (struct mbuf **)0, &rcvflg);
if (error == EWOULDBLOCK && rep) {
if (rep->r_flags & R_SOFTTERM)
return (EINTR);
if (rep->r_flags & R_MUSTRESEND)
goto tryagain;
}
} while (error == EWOULDBLOCK);
if (!error && *mp == NULL)
error = EPIPE;
len -= auio.uio_resid;
}
errout:
if (error && rep && error != EINTR && error != ERESTART) {
m_freem(*mp);
*mp = (struct mbuf *)0;
nfs_disconnect(rep->r_nmp);
error = nfs_reconnect(rep, rep->r_nmp);
if (!error)
goto tryagain;
}
} else {
if (so->so_state & SS_ISCONNECTED)
getnam = (struct mbuf **)0;
else
getnam = aname;
auio.uio_resid = len = 1000000;
do {
error = soreceive(so, getnam, &auio, mp,
(struct mbuf **)0, &rcvflg);
if (error == EWOULDBLOCK && rep &&
(rep->r_flags & R_SOFTTERM))
return (EINTR);
} while (error == EWOULDBLOCK);
len -= auio.uio_resid;
}
if (error) {
m_freem(*mp);
*mp = (struct mbuf *)0;
}
/*
* Search for any mbufs that are not a multiple of 4 bytes long.
* These could cause pointer alignment problems, so copy them to
* well aligned mbufs.
*/
m = *mp;
mbp = mp;
while (m) {
/*
* All this for something that may never happen.
*/
if (m->m_len & 0x3) {
printf("nfs_rcv odd length!\n");
fcp = mtod(m, caddr_t);
mnew = m2 = (struct mbuf *)0;
#ifdef lint
m3 = (struct mbuf *)0;
mlen = 0;
#endif /* lint */
while (m) {
if (m2 == NULL || mlen == 0) {
MGET(m2, M_WAIT, MT_DATA);
if (len > MINCLSIZE)
MCLGET(m2, M_WAIT);
m2->m_len = 0;
mlen = M_TRAILINGSPACE(m2);
tcp = mtod(m2, caddr_t);
if (mnew) {
m3->m_next = m2;
m3 = m2;
} else
mnew = m3 = m2;
}
siz = (mlen > m->m_len) ? m->m_len : mlen;
bcopy(fcp, tcp, siz);
m2->m_len += siz;
mlen -= siz;
len -= siz;
tcp += siz;
m->m_len -= siz;
fcp += siz;
if (m->m_len == 0) {
do {
m = m->m_next;
} while (m && m->m_len == 0);
if (m)
fcp = mtod(m, caddr_t);
}
}
m = *mbp;
*mbp = mnew;
m_freem(m);
break;
}
len -= m->m_len;
mbp = &m->m_next;
m = m->m_next;
}
return (error);
}
struct rpc_replyhead {
u_long r_xid;
u_long r_rep;
};
/*
* Implement receipt of reply on a socket.
* We must search through the list of received datagrams matching them
* with outstanding requests using the xid, until ours is found.
*/
/* ARGSUSED */
nfs_reply(nmp, myrep)
struct nfsmount *nmp;
struct nfsreq *myrep;
{
register struct mbuf *m;
register struct nfsreq *rep;
register int error = 0;
struct rpc_replyhead replyh;
struct mbuf *mp, *nam;
char *cp;
int cnt, xfer;
/*
* Loop around until we get our own reply
*/
for (;;) {
/*
* Lock against other receivers so that I don't get stuck in
* sbwait() after someone else has received my reply for me.
* Also necessary for connection based protocols to avoid
* race conditions during a reconnect.
*/
nfs_solock(&nmp->nm_flag);
/* Already received, bye bye */
if (myrep->r_mrep != NULL) {
nfs_sounlock(&nmp->nm_flag);
return (0);
}
/*
* Get the next Rpc reply off the socket
*/
if (error = nfs_receive(nmp->nm_so, &nam, &mp, myrep)) {
nfs_sounlock(&nmp->nm_flag);
/*
* Ignore routing errors on connectionless protocols??
*/
if (NFSIGNORE_SOERROR(nmp->nm_soflags, error)) {
nmp->nm_so->so_error = 0;
continue;
}
/*
* Otherwise cleanup and return a fatal error.
*/
if (myrep->r_flags & R_TIMING) {
myrep->r_flags &= ~R_TIMING;
nmp->nm_rtt = -1;
}
if (myrep->r_flags & R_SENT) {
myrep->r_flags &= ~R_SENT;
nmp->nm_sent--;
}
return (error);
}
/*
* Get the xid and check that it is an rpc reply
*/
m = mp;
if (m->m_len >= 2*NFSX_UNSIGNED)
bcopy(mtod(m, caddr_t), (caddr_t)&replyh,
2*NFSX_UNSIGNED);
else {
cnt = 2*NFSX_UNSIGNED;
cp = (caddr_t)&replyh;
while (m && cnt > 0) {
if (m->m_len > 0) {
xfer = (m->m_len >= cnt) ? cnt :
m->m_len;
bcopy(mtod(m, caddr_t), cp, xfer);
cnt -= xfer;
cp += xfer;
}
if (cnt > 0)
m = m->m_next;
}
}
if (replyh.r_rep != rpc_reply || m == NULL) {
nfsstats.rpcinvalid++;
m_freem(mp);
nfs_sounlock(&nmp->nm_flag);
continue;
}
/*
* Loop through the request list to match up the reply
* Iff no match, just drop the datagram
*/
m = mp;
rep = nfsreqh.r_next;
while (rep != &nfsreqh) {
if (rep->r_mrep == NULL && replyh.r_xid == rep->r_xid) {
/* Found it.. */
rep->r_mrep = m;
/*
* Update timing
*/
if (rep->r_flags & R_TIMING) {
nfs_updatetimer(rep->r_nmp);
rep->r_flags &= ~R_TIMING;
rep->r_nmp->nm_rtt = -1;
}
if (rep->r_flags & R_SENT) {
rep->r_flags &= ~R_SENT;
rep->r_nmp->nm_sent--;
}
break;
}
rep = rep->r_next;
}
nfs_sounlock(&nmp->nm_flag);
if (nam)
m_freem(nam);
/*
* If not matched to a request, drop it.
* If it's mine, get out.
*/
if (rep == &nfsreqh) {
nfsstats.rpcunexpected++;
m_freem(m);
} else if (rep == myrep)
return (0);
}
}
/*
* nfs_request - goes something like this
* - fill in request struct
* - links it into list
* - calls nfs_send() for first transmit
* - calls nfs_receive() to get reply
* - break down rpc header and return with nfs reply pointed to
* by mrep or error
* nb: always frees up mreq mbuf list
*/
nfs_request(vp, mreq, xid, procnum, procp, tryhard, mp, mrp, mdp, dposp)
struct vnode *vp;
struct mbuf *mreq;
u_long xid;
int procnum;
struct proc *procp;
int tryhard;
struct mount *mp;
struct mbuf **mrp;
struct mbuf **mdp;
caddr_t *dposp;
{
register struct mbuf *m, *mrep;
register struct nfsreq *rep;
register u_long *p;
register int len;
struct nfsmount *nmp;
struct mbuf *md;
struct nfsreq *reph;
caddr_t dpos;
char *cp2;
int t1;
int s;
int error = 0;
nmp = VFSTONFS(mp);
m = mreq;
MALLOC(rep, struct nfsreq *, sizeof(struct nfsreq), M_NFSREQ, M_WAITOK);
rep->r_xid = xid;
rep->r_nmp = nmp;
rep->r_vp = vp;
rep->r_procp = procp;
if ((nmp->nm_flag & NFSMNT_SOFT) ||
((nmp->nm_flag & NFSMNT_SPONGY) && !tryhard))
rep->r_retry = nmp->nm_retry;
else
rep->r_retry = NFS_MAXREXMIT + 1; /* past clip limit */
rep->r_flags = rep->r_rexmit = 0;
/*
* Three cases:
* - non-idempotent requests on SOCK_DGRAM use NFS_MINIDEMTIMEO
* - idempotent requests on SOCK_DGRAM use 0
* - Reliable transports, NFS_RELIABLETIMEO
* Timeouts are still done on reliable transports to ensure detection
* of excessive connection delay.
*/
if (nmp->nm_sotype != SOCK_DGRAM)
rep->r_timerinit = -NFS_RELIABLETIMEO;
else if (nonidempotent[procnum])
rep->r_timerinit = -NFS_MINIDEMTIMEO;
else
rep->r_timerinit = 0;
rep->r_timer = rep->r_timerinit;
rep->r_mrep = NULL;
len = 0;
while (m) {
len += m->m_len;
m = m->m_next;
}
mreq->m_pkthdr.len = len;
mreq->m_pkthdr.rcvif = (struct ifnet *)0;
/*
* For non-atomic protocols, insert a Sun RPC Record Mark.
*/
if ((nmp->nm_soflags & PR_ATOMIC) == 0) {
M_PREPEND(mreq, sizeof(u_long), M_WAIT);
*mtod(mreq, u_long *) = htonl(0x80000000 | len);
}
rep->r_mreq = mreq;
/*
* Do the client side RPC.
*/
nfsstats.rpcrequests++;
/*
* Chain request into list of outstanding requests. Be sure
* to put it LAST so timer finds oldest requests first.
*/
s = splnet();
reph = &nfsreqh;
reph->r_prev->r_next = rep;
rep->r_prev = reph->r_prev;
reph->r_prev = rep;
rep->r_next = reph;
/*
* If backing off another request or avoiding congestion, don't
* send this one now but let timer do it. If not timing a request,
* do it now.
*/
if (nmp->nm_sent <= 0 || nmp->nm_sotype != SOCK_DGRAM ||
(nmp->nm_currexmit == 0 && nmp->nm_sent < nmp->nm_window)) {
nmp->nm_sent++;
rep->r_flags |= R_SENT;
if (nmp->nm_rtt == -1) {
nmp->nm_rtt = 0;
rep->r_flags |= R_TIMING;
}
splx(s);
m = m_copym(mreq, 0, M_COPYALL, M_WAIT);
if (nmp->nm_soflags & PR_CONNREQUIRED)
nfs_solock(&nmp->nm_flag);
error = nfs_send(nmp->nm_so, nmp->nm_nam, m, rep);
if (nmp->nm_soflags & PR_CONNREQUIRED)
nfs_sounlock(&nmp->nm_flag);
if (error && NFSIGNORE_SOERROR(nmp->nm_soflags, error))
nmp->nm_so->so_error = error = 0;
} else
splx(s);
/*
* Wait for the reply from our send or the timer's.
*/
if (!error)
error = nfs_reply(nmp, rep);
/*
* RPC done, unlink the request.
*/
s = splnet();
rep->r_prev->r_next = rep->r_next;
rep->r_next->r_prev = rep->r_prev;
splx(s);
/*
* If there was a successful reply and a tprintf msg.
* tprintf a response.
*/
if (!error && (rep->r_flags & R_TPRINTFMSG)) {
if (rep->r_procp)
tprintf(rep->r_procp->p_session,
"Nfs server %s, is alive again\n",
rep->r_nmp->nm_mountp->mnt_stat.f_mntfromname);
else
tprintf(NULL, "Nfs server %s, is alive again\n",
rep->r_nmp->nm_mountp->mnt_stat.f_mntfromname);
}
m_freem(rep->r_mreq);
mrep = md = rep->r_mrep;
FREE((caddr_t)rep, M_NFSREQ);
if (error)
return (error);
/*
* break down the rpc header and check if ok
*/
dpos = mtod(md, caddr_t);
nfsm_disect(p, u_long *, 5*NFSX_UNSIGNED);
p += 2;
if (*p++ == rpc_msgdenied) {
if (*p == rpc_mismatch)
error = EOPNOTSUPP;
else
error = EACCES;
m_freem(mrep);
return (error);
}
/*
* skip over the auth_verf, someday we may want to cache auth_short's
* for nfs_reqhead(), but for now just dump it
*/
if (*++p != 0) {
len = nfsm_rndup(fxdr_unsigned(long, *p));
nfsm_adv(len);
}
nfsm_disect(p, u_long *, NFSX_UNSIGNED);
/* 0 == ok */
if (*p == 0) {
nfsm_disect(p, u_long *, NFSX_UNSIGNED);
if (*p != 0) {
error = fxdr_unsigned(int, *p);
m_freem(mrep);
return (error);
}
*mrp = mrep;
*mdp = md;
*dposp = dpos;
return (0);
}
m_freem(mrep);
return (EPROTONOSUPPORT);
nfsmout:
return (error);
}
/*
* Get a request for the server main loop
* - receive a request via. nfs_soreceive()
* - verify it
* - fill in the cred struct.
*/
nfs_getreq(so, prog, vers, maxproc, nam, mrp, mdp, dposp, retxid, procnum, cr,
msk, mtch)
struct socket *so;
u_long prog;
u_long vers;
int maxproc;
struct mbuf **nam;
struct mbuf **mrp;
struct mbuf **mdp;
caddr_t *dposp;
u_long *retxid;
u_long *procnum;
register struct ucred *cr;
struct mbuf *msk, *mtch;
{
register int i;
register u_long *p;
register long t1;
caddr_t dpos, cp2;
int error = 0;
struct mbuf *mrep, *md;
int len;
if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
error = nfs_receive(so, nam, &mrep, (struct nfsreq *)0);
} else {
mrep = (struct mbuf *)0;
do {
if (mrep) {
m_freem(*nam);
m_freem(mrep);
}
error = nfs_receive(so, nam, &mrep, (struct nfsreq *)0);
} while (!error && nfs_badnam(*nam, msk, mtch));
}
if (error)
return (error);
md = mrep;
dpos = mtod(mrep, caddr_t);
nfsm_disect(p, u_long *, 10*NFSX_UNSIGNED);
*retxid = *p++;
if (*p++ != rpc_call) {
m_freem(mrep);
return (ERPCMISMATCH);
}
if (*p++ != rpc_vers) {
m_freem(mrep);
return (ERPCMISMATCH);
}
if (*p++ != prog) {
m_freem(mrep);
return (EPROGUNAVAIL);
}
if (*p++ != vers) {
m_freem(mrep);
return (EPROGMISMATCH);
}
*procnum = fxdr_unsigned(u_long, *p++);
if (*procnum == NFSPROC_NULL) {
*mrp = mrep;
return (0);
}
if (*procnum > maxproc || *p++ != rpc_auth_unix) {
m_freem(mrep);
return (EPROCUNAVAIL);
}
len = fxdr_unsigned(int, *p++);
if (len < 0 || len > RPCAUTH_MAXSIZ) {
m_freem(mrep);
return (EBADRPC);
}
len = fxdr_unsigned(int, *++p);
if (len < 0 || len > NFS_MAXNAMLEN) {
m_freem(mrep);
return (EBADRPC);
}
nfsm_adv(nfsm_rndup(len));
nfsm_disect(p, u_long *, 3*NFSX_UNSIGNED);
cr->cr_uid = fxdr_unsigned(uid_t, *p++);
cr->cr_gid = fxdr_unsigned(gid_t, *p++);
len = fxdr_unsigned(int, *p);
if (len < 0 || len > RPCAUTH_UNIXGIDS) {
m_freem(mrep);
return (EBADRPC);
}
nfsm_disect(p, u_long *, (len + 2)*NFSX_UNSIGNED);
for (i = 1; i <= len; i++)
if (i < NGROUPS)
cr->cr_groups[i] = fxdr_unsigned(gid_t, *p++);
else
p++;
cr->cr_ngroups = (len >= NGROUPS) ? NGROUPS : (len + 1);
/*
* Do we have any use for the verifier.
* According to the "Remote Procedure Call Protocol Spec." it
* should be AUTH_NULL, but some clients make it AUTH_UNIX?
* For now, just skip over it
*/
len = fxdr_unsigned(int, *++p);
if (len < 0 || len > RPCAUTH_MAXSIZ) {
m_freem(mrep);
return (EBADRPC);
}
if (len > 0)
nfsm_adv(nfsm_rndup(len));
*mrp = mrep;
*mdp = md;
*dposp = dpos;
return (0);
nfsmout:
return (error);
}
/*
* Generate the rpc reply header
* siz arg. is used to decide if adding a cluster is worthwhile
*/
nfs_rephead(siz, retxid, err, mrq, mbp, bposp)
int siz;
u_long retxid;
int err;
struct mbuf **mrq;
struct mbuf **mbp;
caddr_t *bposp;
{
register u_long *p;
register long t1;
caddr_t bpos;
struct mbuf *mreq, *mb, *mb2;
NFSMGETHDR(mreq);
mb = mreq;
if ((siz+RPC_REPLYSIZ) > MHLEN)
MCLGET(mreq, M_WAIT);
p = mtod(mreq, u_long *);
mreq->m_len = 6*NFSX_UNSIGNED;
bpos = ((caddr_t)p)+mreq->m_len;
*p++ = retxid;
*p++ = rpc_reply;
if (err == ERPCMISMATCH) {
*p++ = rpc_msgdenied;
*p++ = rpc_mismatch;
*p++ = txdr_unsigned(2);
*p = txdr_unsigned(2);
} else {
*p++ = rpc_msgaccepted;
*p++ = 0;
*p++ = 0;
switch (err) {
case EPROGUNAVAIL:
*p = txdr_unsigned(RPC_PROGUNAVAIL);
break;
case EPROGMISMATCH:
*p = txdr_unsigned(RPC_PROGMISMATCH);
nfsm_build(p, u_long *, 2*NFSX_UNSIGNED);
*p++ = txdr_unsigned(2);
*p = txdr_unsigned(2); /* someday 3 */
break;
case EPROCUNAVAIL:
*p = txdr_unsigned(RPC_PROCUNAVAIL);
break;
default:
*p = 0;
if (err != VNOVAL) {
nfsm_build(p, u_long *, NFSX_UNSIGNED);
*p = txdr_unsigned(err);
}
break;
};
}
*mrq = mreq;
*mbp = mb;
*bposp = bpos;
if (err != 0 && err != VNOVAL)
nfsstats.srvrpc_errs++;
return (0);
}
/*
* Nfs timer routine
* Scan the nfsreq list and retranmit any requests that have timed out
* To avoid retransmission attempts on STREAM sockets (in the future) make
* sure to set the r_retry field to 0 (implies nm_retry == 0).
*/
nfs_timer()
{
register struct nfsreq *rep;
register struct mbuf *m;
register struct socket *so;
register struct nfsmount *nmp;
int s, error;
s = splnet();
for (rep = nfsreqh.r_next; rep != &nfsreqh; rep = rep->r_next) {
nmp = rep->r_nmp;
if (rep->r_mrep || (rep->r_flags & R_SOFTTERM) ||
(so = nmp->nm_so) == NULL)
continue;
if ((nmp->nm_flag & NFSMNT_INT) && nfs_sigintr(rep->r_procp)) {
rep->r_flags |= R_SOFTTERM;
continue;
}
if (rep->r_flags & R_TIMING) /* update rtt in mount */
nmp->nm_rtt++;
/* If not timed out */
if (++rep->r_timer < nmp->nm_rto)
continue;
/* Do backoff and save new timeout in mount */
if (rep->r_flags & R_TIMING) {
nfs_backofftimer(nmp);
rep->r_flags &= ~R_TIMING;
nmp->nm_rtt = -1;
}
if (rep->r_flags & R_SENT) {
rep->r_flags &= ~R_SENT;
nmp->nm_sent--;
}
/*
* Check for too many retries on soft mount.
* nb: For hard mounts, r_retry == NFS_MAXREXMIT+1
*/
if (++rep->r_rexmit > NFS_MAXREXMIT)
rep->r_rexmit = NFS_MAXREXMIT;
/*
* Check for server not responding
*/
if ((rep->r_flags & R_TPRINTFMSG) == 0 &&
rep->r_rexmit > NFS_FISHY) {
if (rep->r_procp && rep->r_procp->p_session)
tprintf(rep->r_procp->p_session,
"Nfs server %s, not responding\n",
nmp->nm_mountp->mnt_stat.f_mntfromname);
else
tprintf(NULL,
"Nfs server %s, not responding\n",
nmp->nm_mountp->mnt_stat.f_mntfromname);
rep->r_flags |= R_TPRINTFMSG;
}
if (rep->r_rexmit >= rep->r_retry) { /* too many */
nfsstats.rpctimeouts++;
rep->r_flags |= R_SOFTTERM;
continue;
}
if (nmp->nm_sotype != SOCK_DGRAM)
continue;
/*
* If there is enough space and the window allows..
* Resend it
*/
if (sbspace(&so->so_snd) >= rep->r_mreq->m_pkthdr.len &&
nmp->nm_sent < nmp->nm_window &&
(m = m_copym(rep->r_mreq, 0, M_COPYALL, M_DONTWAIT))){
nfsstats.rpcretries++;
if ((nmp->nm_flag & NFSMNT_NOCONN) == 0)
error = (*so->so_proto->pr_usrreq)(so, PRU_SEND, m,
(caddr_t)0, (struct mbuf *)0, (struct mbuf *)0);
else
error = (*so->so_proto->pr_usrreq)(so, PRU_SEND, m,
nmp->nm_nam, (struct mbuf *)0, (struct mbuf *)0);
if (error) {
if (NFSIGNORE_SOERROR(nmp->nm_soflags, error))
so->so_error = 0;
} else {
/*
* We need to time the request even though we
* are retransmitting.
*/
nmp->nm_rtt = 0;
nmp->nm_sent++;
rep->r_flags |= (R_SENT|R_TIMING);
rep->r_timer = rep->r_timerinit;
}
}
}
splx(s);
timeout(nfs_timer, (caddr_t)0, hz/NFS_HZ);
}
/*
* NFS timer update and backoff. The "Jacobson/Karels/Karn" scheme is
* used here. The timer state is held in the nfsmount structure and
* a single request is used to clock the response. When successful
* the rtt smoothing in nfs_updatetimer is used, when failed the backoff
* is done by nfs_backofftimer. We also log failure messages in these
* routines.
*
* Congestion variables are held in the nfshost structure which
* is referenced by nfsmounts and shared per-server. This separation
* makes it possible to do per-mount timing which allows varying disk
* access times to be dealt with, while preserving a network oriented
* congestion control scheme.
*
* The windowing implements the Jacobson/Karels slowstart algorithm
* with adjusted scaling factors. We start with one request, then send
* 4 more after each success until the ssthresh limit is reached, then
* we increment at a rate proportional to the window. On failure, we
* remember 3/4 the current window and clamp the send limit to 1. Note
* ICMP source quench is not reflected in so->so_error so we ignore that
* for now.
*
* NFS behaves much more like a transport protocol with these changes,
* shedding the teenage pedal-to-the-metal tendencies of "other"
* implementations.
*
* Timers and congestion avoidance by Tom Talpey, Open Software Foundation.
*/
/*
* The TCP algorithm was not forgiving enough. Because the NFS server
* responds only after performing lookups/diskio/etc, we have to be
* more prepared to accept a spiky variance. The TCP algorithm is:
* TCP_RTO(nmp) ((((nmp)->nm_srtt >> 2) + (nmp)->nm_rttvar) >> 1)
*/
#define NFS_RTO(nmp) (((nmp)->nm_srtt >> 3) + (nmp)->nm_rttvar)
nfs_updatetimer(nmp)
register struct nfsmount *nmp;
{
/* If retransmitted, clear and return */
if (nmp->nm_rexmit || nmp->nm_currexmit) {
nmp->nm_rexmit = nmp->nm_currexmit = 0;
return;
}
/* If have a measurement, do smoothing */
if (nmp->nm_srtt) {
register short delta;
delta = nmp->nm_rtt - (nmp->nm_srtt >> 3);
if ((nmp->nm_srtt += delta) <= 0)
nmp->nm_srtt = 1;
if (delta < 0)
delta = -delta;
delta -= (nmp->nm_rttvar >> 2);
if ((nmp->nm_rttvar += delta) <= 0)
nmp->nm_rttvar = 1;
/* Else initialize */
} else {
nmp->nm_rttvar = nmp->nm_rtt << 1;
if (nmp->nm_rttvar == 0) nmp->nm_rttvar = 2;
nmp->nm_srtt = nmp->nm_rttvar << 2;
}
/* Compute new Retransmission TimeOut and clip */
nmp->nm_rto = NFS_RTO(nmp);
if (nmp->nm_rto < NFS_MINTIMEO)
nmp->nm_rto = NFS_MINTIMEO;
else if (nmp->nm_rto > NFS_MAXTIMEO)
nmp->nm_rto = NFS_MAXTIMEO;
/* Update window estimate */
if (nmp->nm_window < nmp->nm_ssthresh) /* quickly */
nmp->nm_window += 4;
else { /* slowly */
register long incr = ++nmp->nm_winext;
incr = (incr * incr) / nmp->nm_window;
if (incr > 0) {
nmp->nm_winext = 0;
++nmp->nm_window;
}
}
if (nmp->nm_window > NFS_MAXWINDOW)
nmp->nm_window = NFS_MAXWINDOW;
}
nfs_backofftimer(nmp)
register struct nfsmount *nmp;
{
register unsigned long newrto;
/* Clip shift count */
if (++nmp->nm_rexmit > 8 * sizeof nmp->nm_rto)
nmp->nm_rexmit = 8 * sizeof nmp->nm_rto;
/* Back off RTO exponentially */
newrto = NFS_RTO(nmp);
newrto <<= (nmp->nm_rexmit - 1);
if (newrto == 0 || newrto > NFS_MAXTIMEO)
newrto = NFS_MAXTIMEO;
nmp->nm_rto = newrto;
/* If too many retries, message, assume a bogus RTT and re-measure */
if (nmp->nm_currexmit < nmp->nm_rexmit) {
nmp->nm_currexmit = nmp->nm_rexmit;
if (nmp->nm_currexmit >= nfsrexmtthresh) {
if (nmp->nm_currexmit == nfsrexmtthresh) {
nmp->nm_rttvar += (nmp->nm_srtt >> 2);
nmp->nm_srtt = 0;
}
}
}
/* Close down window but remember this point (3/4 current) for later */
nmp->nm_ssthresh = ((nmp->nm_window << 1) + nmp->nm_window) >> 2;
nmp->nm_window = 1;
nmp->nm_winext = 0;
}
/*
* Test for a termination signal pending on procp.
* This is used for NFSMNT_INT mounts.
*/
nfs_sigintr(p)
register struct proc *p;
{
if (p && p->p_sig && (((p->p_sig &~ p->p_sigmask) &~ p->p_sigignore) &
NFSINT_SIGMASK))
return (1);
else
return (0);
}
/*
* Lock a socket against others.
* Necessary for STREAM sockets to ensure you get an entire rpc request/reply
* and also to avoid race conditions between the processes with nfs requests
* in progress when a reconnect is necessary.
*/
nfs_solock(flagp)
register int *flagp;
{
while (*flagp & NFSMNT_SCKLOCK) {
*flagp |= NFSMNT_WANTSCK;
(void) tsleep((caddr_t)flagp, PZERO-1, "nfsolck", 0);
}
*flagp |= NFSMNT_SCKLOCK;
}
/*
* Unlock the stream socket for others.
*/
nfs_sounlock(flagp)
register int *flagp;
{
if ((*flagp & NFSMNT_SCKLOCK) == 0)
panic("nfs sounlock");
*flagp &= ~NFSMNT_SCKLOCK;
if (*flagp & NFSMNT_WANTSCK) {
*flagp &= ~NFSMNT_WANTSCK;
wakeup((caddr_t)flagp);
}
}
/*
* This function compares two net addresses by family and returns TRUE
* if they are the same.
* If there is any doubt, return FALSE.
*/
nfs_netaddr_match(nam1, nam2)
struct mbuf *nam1, *nam2;
{
register struct sockaddr *saddr1, *saddr2;
saddr1 = mtod(nam1, struct sockaddr *);
saddr2 = mtod(nam2, struct sockaddr *);
if (saddr1->sa_family != saddr2->sa_family)
return (0);
/*
* Must do each address family separately since unused fields
* are undefined values and not always zeroed.
*/
switch (saddr1->sa_family) {
case AF_INET:
if (((struct sockaddr_in *)saddr1)->sin_addr.s_addr ==
((struct sockaddr_in *)saddr2)->sin_addr.s_addr)
return (1);
break;
default:
break;
};
return (0);
}
/*
* Check the hostname fields for nfsd's mask and match fields.
* By address family:
* - Bitwise AND the mask with the host address field
* - Compare for == with match
* return TRUE if not equal
*/
nfs_badnam(nam, msk, mtch)
register struct mbuf *nam, *msk, *mtch;
{
switch (mtod(nam, struct sockaddr *)->sa_family) {
case AF_INET:
return ((mtod(nam, struct sockaddr_in *)->sin_addr.s_addr &
mtod(msk, struct sockaddr_in *)->sin_addr.s_addr) !=
mtod(mtch, struct sockaddr_in *)->sin_addr.s_addr);
default:
printf("nfs_badmatch, unknown sa_family\n");
return (0);
};
}