d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
4b38eed76d
freebsd-dev/sys/rpc/clnt_rc.c
Rick Macklem 7763814fc9 nfsv4 client: do the BindConnectionToSession as required 
During a recent testing event, it was reported that the NFSv4.1/4.2
server erroneously bound the back channel to a new TCP connection.
RFC5661 specifies that the fore channel is implicitly bound to a
new TCP connection when an RPC with Sequence (almost any of them)
is done on it.  For the back channel to be bound to the new TCP
connection, an explicit BindConnectionToSession must be done as
the first RPC on the new connection.

Since new TCP connections are created by the "reconnect" layer
(sys/rpc/clnt_rc.c) of the krpc, this patch adds an optional
upcall done by the krpc whenever a new connection is created.
The patch also adds the specific upcall function that does a
BindConnectionToSession and configures the krpc to call it
when required.

This is necessary for correct interoperability with NFSv4.1/NFSv4.2
servers when the nfscbd daemon is running.

If doing NFSv4.1/NFSv4.2 mounts without this patch, it is
recommended that the nfscbd daemon not be running and that
the "pnfs" mount option not be specified.

PR:	254840
Comments by:	asomers
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D29475
2021-04-11 14:34:57 -07:00

582 lines
15 KiB
C
Raw Blame History

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2008 Isilon Inc http://www.isilon.com/
* Authors: Doug Rabson <dfr@rabson.org>
* Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org>
*
* 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/systm.h>
#include <sys/kernel.h>
#include <sys/limits.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/mutex.h>
#include <sys/pcpu.h>
#include <sys/proc.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/time.h>
#include <sys/uio.h>
#include <rpc/rpc.h>
#include <rpc/rpc_com.h>
#include <rpc/krpc.h>
#include <rpc/rpcsec_tls.h>
static enum clnt_stat clnt_reconnect_call(CLIENT *, struct rpc_callextra *,
rpcproc_t, struct mbuf *, struct mbuf **, struct timeval);
static void clnt_reconnect_geterr(CLIENT *, struct rpc_err *);
static bool_t clnt_reconnect_freeres(CLIENT *, xdrproc_t, void *);
static void clnt_reconnect_abort(CLIENT *);
static bool_t clnt_reconnect_control(CLIENT *, u_int, void *);
static void clnt_reconnect_close(CLIENT *);
static void clnt_reconnect_destroy(CLIENT *);
static struct clnt_ops clnt_reconnect_ops = {
.cl_call = clnt_reconnect_call,
.cl_abort = clnt_reconnect_abort,
.cl_geterr = clnt_reconnect_geterr,
.cl_freeres = clnt_reconnect_freeres,
.cl_close = clnt_reconnect_close,
.cl_destroy = clnt_reconnect_destroy,
.cl_control = clnt_reconnect_control
};
static int fake_wchan;
CLIENT *
clnt_reconnect_create(
struct netconfig *nconf, /* network type */
struct sockaddr *svcaddr, /* servers address */
rpcprog_t program, /* program number */
rpcvers_t version, /* version number */
size_t sendsz, /* buffer recv size */
size_t recvsz) /* buffer send size */
{
CLIENT *cl = NULL; /* client handle */
struct rc_data *rc = NULL; /* private data */
if (svcaddr == NULL) {
rpc_createerr.cf_stat = RPC_UNKNOWNADDR;
return (NULL);
}
cl = mem_alloc(sizeof (CLIENT));
rc = mem_alloc(sizeof (*rc));
mtx_init(&rc->rc_lock, "rc->rc_lock", NULL, MTX_DEF);
(void) memcpy(&rc->rc_addr, svcaddr, (size_t)svcaddr->sa_len);
rc->rc_nconf = nconf;
rc->rc_prog = program;
rc->rc_vers = version;
rc->rc_sendsz = sendsz;
rc->rc_recvsz = recvsz;
rc->rc_timeout.tv_sec = -1;
rc->rc_timeout.tv_usec = -1;
rc->rc_retry.tv_sec = 3;
rc->rc_retry.tv_usec = 0;
rc->rc_retries = INT_MAX;
rc->rc_privport = FALSE;
rc->rc_waitchan = "rpcrecv";
rc->rc_intr = 0;
rc->rc_connecting = FALSE;
rc->rc_closed = FALSE;
rc->rc_ucred = crdup(curthread->td_ucred);
rc->rc_client = NULL;
rc->rc_tls = false;
rc->rc_tlscertname = NULL;
rc->rc_reconcall = NULL;
rc->rc_reconarg = NULL;
cl->cl_refs = 1;
cl->cl_ops = &clnt_reconnect_ops;
cl->cl_private = (caddr_t)(void *)rc;
cl->cl_auth = authnone_create();
cl->cl_tp = NULL;
cl->cl_netid = NULL;
return (cl);
}
static enum clnt_stat
clnt_reconnect_connect(CLIENT *cl)
{
struct thread *td = curthread;
struct rc_data *rc = (struct rc_data *)cl->cl_private;
struct socket *so;
enum clnt_stat stat;
int error;
int one = 1;
struct ucred *oldcred;
CLIENT *newclient = NULL;
uint64_t ssl[3];
uint32_t reterr;
mtx_lock(&rc->rc_lock);
while (rc->rc_connecting) {
error = msleep(rc, &rc->rc_lock,
rc->rc_intr ? PCATCH : 0, "rpcrecon", 0);
if (error) {
mtx_unlock(&rc->rc_lock);
return (RPC_INTR);
}
}
if (rc->rc_closed) {
mtx_unlock(&rc->rc_lock);
return (RPC_CANTSEND);
}
if (rc->rc_client) {
mtx_unlock(&rc->rc_lock);
return (RPC_SUCCESS);
}
/*
* My turn to attempt a connect. The rc_connecting variable
* serializes the following code sequence, so it is guaranteed
* that rc_client will still be NULL after it is re-locked below,
* since that is the only place it is set non-NULL.
*/
rc->rc_connecting = TRUE;
mtx_unlock(&rc->rc_lock);
oldcred = td->td_ucred;
td->td_ucred = rc->rc_ucred;
so = __rpc_nconf2socket(rc->rc_nconf);
if (!so) {
stat = rpc_createerr.cf_stat = RPC_TLIERROR;
rpc_createerr.cf_error.re_errno = 0;
td->td_ucred = oldcred;
goto out;
}
if (rc->rc_privport)
bindresvport(so, NULL);
if (rc->rc_nconf->nc_semantics == NC_TPI_CLTS)
newclient = clnt_dg_create(so,
(struct sockaddr *) &rc->rc_addr, rc->rc_prog, rc->rc_vers,
rc->rc_sendsz, rc->rc_recvsz);
else {
/*
* I do not believe a timeout of less than 1sec would make
* sense here since short delays can occur when a server is
* temporarily overloaded.
*/
if (rc->rc_timeout.tv_sec > 0 && rc->rc_timeout.tv_usec >= 0) {
error = so_setsockopt(so, SOL_SOCKET, SO_SNDTIMEO,
&rc->rc_timeout, sizeof(struct timeval));
if (error != 0) {
stat = rpc_createerr.cf_stat = RPC_CANTSEND;
rpc_createerr.cf_error.re_errno = error;
td->td_ucred = oldcred;
goto out;
}
}
newclient = clnt_vc_create(so,
(struct sockaddr *) &rc->rc_addr, rc->rc_prog, rc->rc_vers,
rc->rc_sendsz, rc->rc_recvsz, rc->rc_intr);
if (rc->rc_tls && newclient != NULL) {
stat = rpctls_connect(newclient, rc->rc_tlscertname, so,
ssl, &reterr);
if (stat != RPC_SUCCESS || reterr != RPCTLSERR_OK) {
if (stat == RPC_SUCCESS)
stat = RPC_FAILED;
stat = rpc_createerr.cf_stat = stat;
rpc_createerr.cf_error.re_errno = 0;
CLNT_CLOSE(newclient);
CLNT_RELEASE(newclient);
newclient = NULL;
td->td_ucred = oldcred;
goto out;
}
}
if (newclient != NULL && rc->rc_reconcall != NULL)
(*rc->rc_reconcall)(newclient, rc->rc_reconarg,
rc->rc_ucred);
}
td->td_ucred = oldcred;
if (!newclient) {
soclose(so);
rc->rc_err = rpc_createerr.cf_error;
stat = rpc_createerr.cf_stat;
goto out;
}
CLNT_CONTROL(newclient, CLSET_FD_CLOSE, 0);
CLNT_CONTROL(newclient, CLSET_CONNECT, &one);
CLNT_CONTROL(newclient, CLSET_TIMEOUT, &rc->rc_timeout);
CLNT_CONTROL(newclient, CLSET_RETRY_TIMEOUT, &rc->rc_retry);
CLNT_CONTROL(newclient, CLSET_WAITCHAN, rc->rc_waitchan);
CLNT_CONTROL(newclient, CLSET_INTERRUPTIBLE, &rc->rc_intr);
if (rc->rc_tls)
CLNT_CONTROL(newclient, CLSET_TLS, ssl);
if (rc->rc_backchannel != NULL)
CLNT_CONTROL(newclient, CLSET_BACKCHANNEL, rc->rc_backchannel);
stat = RPC_SUCCESS;
out:
mtx_lock(&rc->rc_lock);
KASSERT(rc->rc_client == NULL, ("rc_client not null"));
if (!rc->rc_closed) {
rc->rc_client = newclient;
newclient = NULL;
}
rc->rc_connecting = FALSE;
wakeup(rc);
mtx_unlock(&rc->rc_lock);
if (newclient) {
/*
* It has been closed, so discard the new client.
* nb: clnt_[dg|vc]_close()/clnt_[dg|vc]_destroy() cannot
* be called with the rc_lock mutex held, since they may
* msleep() while holding a different mutex.
*/
CLNT_CLOSE(newclient);
CLNT_RELEASE(newclient);
}
return (stat);
}
static enum clnt_stat
clnt_reconnect_call(
CLIENT *cl, /* client handle */
struct rpc_callextra *ext, /* call metadata */
rpcproc_t proc, /* procedure number */
struct mbuf *args, /* pointer to args */
struct mbuf **resultsp, /* pointer to results */
struct timeval utimeout)
{
struct rc_data *rc = (struct rc_data *)cl->cl_private;
CLIENT *client;
enum clnt_stat stat;
int tries, error;
tries = 0;
do {
mtx_lock(&rc->rc_lock);
if (rc->rc_closed) {
mtx_unlock(&rc->rc_lock);
return (RPC_CANTSEND);
}
if (!rc->rc_client) {
mtx_unlock(&rc->rc_lock);
stat = clnt_reconnect_connect(cl);
if (stat == RPC_SYSTEMERROR) {
error = tsleep(&fake_wchan,
rc->rc_intr ? PCATCH : 0, "rpccon", hz);
if (error == EINTR || error == ERESTART)
return (RPC_INTR);
tries++;
if (tries >= rc->rc_retries)
return (stat);
continue;
}
if (stat != RPC_SUCCESS)
return (stat);
mtx_lock(&rc->rc_lock);
}
if (!rc->rc_client) {
mtx_unlock(&rc->rc_lock);
stat = RPC_FAILED;
continue;
}
CLNT_ACQUIRE(rc->rc_client);
client = rc->rc_client;
mtx_unlock(&rc->rc_lock);
stat = CLNT_CALL_MBUF(client, ext, proc, args,
resultsp, utimeout);
if (stat != RPC_SUCCESS) {
if (!ext)
CLNT_GETERR(client, &rc->rc_err);
}
if (stat == RPC_TIMEDOUT) {
/*
* Check for async send misfeature for NLM
* protocol.
*/
if ((rc->rc_timeout.tv_sec == 0
&& rc->rc_timeout.tv_usec == 0)
|| (rc->rc_timeout.tv_sec == -1
&& utimeout.tv_sec == 0
&& utimeout.tv_usec == 0)) {
CLNT_RELEASE(client);
break;
}
}
if (stat == RPC_TIMEDOUT || stat == RPC_CANTSEND
|| stat == RPC_CANTRECV) {
tries++;
if (tries >= rc->rc_retries) {
CLNT_RELEASE(client);
break;
}
if (ext && ext->rc_feedback)
ext->rc_feedback(FEEDBACK_RECONNECT, proc,
ext->rc_feedback_arg);
mtx_lock(&rc->rc_lock);
/*
* Make sure that someone else hasn't already
* reconnected by checking if rc_client has changed.
* If not, we are done with the client and must
* do CLNT_RELEASE(client) twice to dispose of it,
* because there is both an initial refcnt and one
* acquired by CLNT_ACQUIRE() above.
*/
if (rc->rc_client == client) {
rc->rc_client = NULL;
mtx_unlock(&rc->rc_lock);
CLNT_RELEASE(client);
} else {
mtx_unlock(&rc->rc_lock);
}
CLNT_RELEASE(client);
} else {
CLNT_RELEASE(client);
break;
}
} while (stat != RPC_SUCCESS);
KASSERT(stat != RPC_SUCCESS || *resultsp,
("RPC_SUCCESS without reply"));
return (stat);
}
static void
clnt_reconnect_geterr(CLIENT *cl, struct rpc_err *errp)
{
struct rc_data *rc = (struct rc_data *)cl->cl_private;
*errp = rc->rc_err;
}
/*
* Since this function requires that rc_client be valid, it can
* only be called when that is guaranteed to be the case.
*/
static bool_t
clnt_reconnect_freeres(CLIENT *cl, xdrproc_t xdr_res, void *res_ptr)
{
struct rc_data *rc = (struct rc_data *)cl->cl_private;
return (CLNT_FREERES(rc->rc_client, xdr_res, res_ptr));
}
/*ARGSUSED*/
static void
clnt_reconnect_abort(CLIENT *h)
{
}
/*
* CLNT_CONTROL() on the client returned by clnt_reconnect_create() must
* always be called before CLNT_CALL_MBUF() by a single thread only.
*/
static bool_t
clnt_reconnect_control(CLIENT *cl, u_int request, void *info)
{
struct rc_data *rc = (struct rc_data *)cl->cl_private;
SVCXPRT *xprt;
size_t slen;
struct rpc_reconupcall *upcp;
if (info == NULL) {
return (FALSE);
}
switch (request) {
case CLSET_TIMEOUT:
rc->rc_timeout = *(struct timeval *)info;
if (rc->rc_client)
CLNT_CONTROL(rc->rc_client, request, info);
break;
case CLGET_TIMEOUT:
*(struct timeval *)info = rc->rc_timeout;
break;
case CLSET_RETRY_TIMEOUT:
rc->rc_retry = *(struct timeval *)info;
if (rc->rc_client)
CLNT_CONTROL(rc->rc_client, request, info);
break;
case CLGET_RETRY_TIMEOUT:
*(struct timeval *)info = rc->rc_retry;
break;
case CLGET_VERS:
*(uint32_t *)info = rc->rc_vers;
break;
case CLSET_VERS:
rc->rc_vers = *(uint32_t *) info;
if (rc->rc_client)
CLNT_CONTROL(rc->rc_client, CLSET_VERS, info);
break;
case CLGET_PROG:
*(uint32_t *)info = rc->rc_prog;
break;
case CLSET_PROG:
rc->rc_prog = *(uint32_t *) info;
if (rc->rc_client)
CLNT_CONTROL(rc->rc_client, request, info);
break;
case CLSET_WAITCHAN:
rc->rc_waitchan = (char *)info;
if (rc->rc_client)
CLNT_CONTROL(rc->rc_client, request, info);
break;
case CLGET_WAITCHAN:
*(const char **) info = rc->rc_waitchan;
break;
case CLSET_INTERRUPTIBLE:
rc->rc_intr = *(int *) info;
if (rc->rc_client)
CLNT_CONTROL(rc->rc_client, request, info);
break;
case CLGET_INTERRUPTIBLE:
*(int *) info = rc->rc_intr;
break;
case CLSET_RETRIES:
rc->rc_retries = *(int *) info;
break;
case CLGET_RETRIES:
*(int *) info = rc->rc_retries;
break;
case CLSET_PRIVPORT:
rc->rc_privport = *(int *) info;
break;
case CLGET_PRIVPORT:
*(int *) info = rc->rc_privport;
break;
case CLSET_BACKCHANNEL:
xprt = (SVCXPRT *)info;
xprt_register(xprt);
rc->rc_backchannel = info;
break;
case CLSET_TLS:
rc->rc_tls = true;
break;
case CLSET_TLSCERTNAME:
slen = strlen(info) + 1;
/*
* tlscertname with "key.pem" appended to it forms a file
* name. As such, the maximum allowable strlen(info) is
* NAME_MAX - 7. However, "slen" includes the nul termination
* byte so it can be up to NAME_MAX - 6.
*/
if (slen <= 1 || slen > NAME_MAX - 6)
return (FALSE);
rc->rc_tlscertname = mem_alloc(slen);
strlcpy(rc->rc_tlscertname, info, slen);
break;
case CLSET_RECONUPCALL:
upcp = (struct rpc_reconupcall *)info;
rc->rc_reconcall = upcp->call;
rc->rc_reconarg = upcp->arg;
break;
default:
return (FALSE);
}
return (TRUE);
}
static void
clnt_reconnect_close(CLIENT *cl)
{
struct rc_data *rc = (struct rc_data *)cl->cl_private;
CLIENT *client;
mtx_lock(&rc->rc_lock);
if (rc->rc_closed) {
mtx_unlock(&rc->rc_lock);
return;
}
rc->rc_closed = TRUE;
client = rc->rc_client;
rc->rc_client = NULL;
mtx_unlock(&rc->rc_lock);
if (client) {
CLNT_CLOSE(client);
CLNT_RELEASE(client);
}
}
static void
clnt_reconnect_destroy(CLIENT *cl)
{
struct rc_data *rc = (struct rc_data *)cl->cl_private;
SVCXPRT *xprt;
if (rc->rc_client)
CLNT_DESTROY(rc->rc_client);
if (rc->rc_backchannel) {
xprt = (SVCXPRT *)rc->rc_backchannel;
KASSERT(xprt->xp_socket == NULL,
("clnt_reconnect_destroy: xp_socket not NULL"));
xprt_unregister(xprt);
SVC_RELEASE(xprt);
}
crfree(rc->rc_ucred);
mtx_destroy(&rc->rc_lock);
mem_free(rc->rc_tlscertname, 0); /* 0 ok, since arg. ignored. */
mem_free(rc->rc_reconarg, 0);
mem_free(rc, sizeof(*rc));
mem_free(cl, sizeof (CLIENT));
}
Reference in New Issue View Git Blame Copy Permalink