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freebsd-dev/sys/rpc/svc_vc.c
Gleb Smirnoff 779f106aa1 Listening sockets improvements. 
o Separate fields of struct socket that belong to listening from
  fields that belong to normal dataflow, and unionize them.  This
  shrinks the structure a bit.
  - Take out selinfo's from the socket buffers into the socket. The
    first reason is to support braindamaged scenario when a socket is
    added to kevent(2) and then listen(2) is cast on it. The second
    reason is that there is future plan to make socket buffers pluggable,
    so that for a dataflow socket a socket buffer can be changed, and
    in this case we also want to keep same selinfos through the lifetime
    of a socket.
  - Remove struct struct so_accf. Since now listening stuff no longer
    affects struct socket size, just move its fields into listening part
    of the union.
  - Provide sol_upcall field and enforce that so_upcall_set() may be called
    only on a dataflow socket, which has buffers, and for listening sockets
    provide solisten_upcall_set().

o Remove ACCEPT_LOCK() global.
  - Add a mutex to socket, to be used instead of socket buffer lock to lock
    fields of struct socket that don't belong to a socket buffer.
  - Allow to acquire two socket locks, but the first one must belong to a
    listening socket.
  - Make soref()/sorele() to use atomic(9).  This allows in some situations
    to do soref() without owning socket lock.  There is place for improvement
    here, it is possible to make sorele() also to lock optionally.
  - Most protocols aren't touched by this change, except UNIX local sockets.
    See below for more information.

o Reduce copy-and-paste in kernel modules that accept connections from
  listening sockets: provide function solisten_dequeue(), and use it in
  the following modules: ctl(4), iscsi(4), ng_btsocket(4), ng_ksocket(4),
  infiniband, rpc.

o UNIX local sockets.
  - Removal of ACCEPT_LOCK() global uncovered several races in the UNIX
    local sockets.  Most races exist around spawning a new socket, when we
    are connecting to a local listening socket.  To cover them, we need to
    hold locks on both PCBs when spawning a third one.  This means holding
    them across sonewconn().  This creates a LOR between pcb locks and
    unp_list_lock.
  - To fix the new LOR, abandon the global unp_list_lock in favor of global
    unp_link_lock.  Indeed, separating these two locks didn't provide us any
    extra parralelism in the UNIX sockets.
  - Now call into uipc_attach() may happen with unp_link_lock hold if, we
    are accepting, or without unp_link_lock in case if we are just creating
    a socket.
  - Another problem in UNIX sockets is that uipc_close() basicly did nothing
    for a listening socket.  The vnode remained opened for connections.  This
    is fixed by removing vnode in uipc_close().  Maybe the right way would be
    to do it for all sockets (not only listening), simply move the vnode
    teardown from uipc_detach() to uipc_close()?

Sponsored by:		Netflix
Differential Revision:	https://reviews.freebsd.org/D9770
2017-06-08 21:30:34 +00:00

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/* $NetBSD: svc_vc.c,v 1.7 2000/08/03 00:01:53 fvdl Exp $ */
/*-
* Copyright (c) 2009, Sun Microsystems, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* - 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.
* - Neither the name of Sun Microsystems, Inc. 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 COPYRIGHT HOLDERS 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 COPYRIGHT HOLDER 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char *sccsid2 = "@(#)svc_tcp.c 1.21 87/08/11 Copyr 1984 Sun Micro";
static char *sccsid = "@(#)svc_tcp.c 2.2 88/08/01 4.0 RPCSRC";
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* svc_vc.c, Server side for Connection Oriented based RPC.
*
* Actually implements two flavors of transporter -
* a tcp rendezvouser (a listner and connection establisher)
* and a record/tcp stream.
*/
#include <sys/param.h>
#include <sys/lock.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/protosw.h>
#include <sys/queue.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sx.h>
#include <sys/systm.h>
#include <sys/uio.h>
#include <net/vnet.h>
#include <netinet/tcp.h>
#include <rpc/rpc.h>
#include <rpc/krpc.h>
#include <rpc/rpc_com.h>
#include <security/mac/mac_framework.h>
static bool_t svc_vc_rendezvous_recv(SVCXPRT *, struct rpc_msg *,
struct sockaddr **, struct mbuf **);
static enum xprt_stat svc_vc_rendezvous_stat(SVCXPRT *);
static void svc_vc_rendezvous_destroy(SVCXPRT *);
static bool_t svc_vc_null(void);
static void svc_vc_destroy(SVCXPRT *);
static enum xprt_stat svc_vc_stat(SVCXPRT *);
static bool_t svc_vc_ack(SVCXPRT *, uint32_t *);
static bool_t svc_vc_recv(SVCXPRT *, struct rpc_msg *,
struct sockaddr **, struct mbuf **);
static bool_t svc_vc_reply(SVCXPRT *, struct rpc_msg *,
struct sockaddr *, struct mbuf *, uint32_t *seq);
static bool_t svc_vc_control(SVCXPRT *xprt, const u_int rq, void *in);
static bool_t svc_vc_rendezvous_control (SVCXPRT *xprt, const u_int rq,
void *in);
static void svc_vc_backchannel_destroy(SVCXPRT *);
static enum xprt_stat svc_vc_backchannel_stat(SVCXPRT *);
static bool_t svc_vc_backchannel_recv(SVCXPRT *, struct rpc_msg *,
struct sockaddr **, struct mbuf **);
static bool_t svc_vc_backchannel_reply(SVCXPRT *, struct rpc_msg *,
struct sockaddr *, struct mbuf *, uint32_t *);
static bool_t svc_vc_backchannel_control(SVCXPRT *xprt, const u_int rq,
void *in);
static SVCXPRT *svc_vc_create_conn(SVCPOOL *pool, struct socket *so,
struct sockaddr *raddr);
static int svc_vc_accept(struct socket *head, struct socket **sop);
static int svc_vc_soupcall(struct socket *so, void *arg, int waitflag);
static int svc_vc_rendezvous_soupcall(struct socket *, void *, int);
static struct xp_ops svc_vc_rendezvous_ops = {
.xp_recv = svc_vc_rendezvous_recv,
.xp_stat = svc_vc_rendezvous_stat,
.xp_reply = (bool_t (*)(SVCXPRT *, struct rpc_msg *,
struct sockaddr *, struct mbuf *, uint32_t *))svc_vc_null,
.xp_destroy = svc_vc_rendezvous_destroy,
.xp_control = svc_vc_rendezvous_control
};
static struct xp_ops svc_vc_ops = {
.xp_recv = svc_vc_recv,
.xp_stat = svc_vc_stat,
.xp_ack = svc_vc_ack,
.xp_reply = svc_vc_reply,
.xp_destroy = svc_vc_destroy,
.xp_control = svc_vc_control
};
static struct xp_ops svc_vc_backchannel_ops = {
.xp_recv = svc_vc_backchannel_recv,
.xp_stat = svc_vc_backchannel_stat,
.xp_reply = svc_vc_backchannel_reply,
.xp_destroy = svc_vc_backchannel_destroy,
.xp_control = svc_vc_backchannel_control
};
/*
* Usage:
* xprt = svc_vc_create(sock, send_buf_size, recv_buf_size);
*
* Creates, registers, and returns a (rpc) tcp based transporter.
* Once *xprt is initialized, it is registered as a transporter
* see (svc.h, xprt_register). This routine returns
* a NULL if a problem occurred.
*
* The filedescriptor passed in is expected to refer to a bound, but
* not yet connected socket.
*
* Since streams do buffered io similar to stdio, the caller can specify
* how big the send and receive buffers are via the second and third parms;
* 0 => use the system default.
*/
SVCXPRT *
svc_vc_create(SVCPOOL *pool, struct socket *so, size_t sendsize,
size_t recvsize)
{
SVCXPRT *xprt;
struct sockaddr* sa;
int error;
SOCK_LOCK(so);
if (so->so_state & (SS_ISCONNECTED|SS_ISDISCONNECTED)) {
SOCK_UNLOCK(so);
CURVNET_SET(so->so_vnet);
error = so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa);
CURVNET_RESTORE();
if (error)
return (NULL);
xprt = svc_vc_create_conn(pool, so, sa);
free(sa, M_SONAME);
return (xprt);
}
SOCK_UNLOCK(so);
xprt = svc_xprt_alloc();
sx_init(&xprt->xp_lock, "xprt->xp_lock");
xprt->xp_pool = pool;
xprt->xp_socket = so;
xprt->xp_p1 = NULL;
xprt->xp_p2 = NULL;
xprt->xp_ops = &svc_vc_rendezvous_ops;
CURVNET_SET(so->so_vnet);
error = so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa);
CURVNET_RESTORE();
if (error) {
goto cleanup_svc_vc_create;
}
memcpy(&xprt->xp_ltaddr, sa, sa->sa_len);
free(sa, M_SONAME);
xprt_register(xprt);
solisten(so, -1, curthread);
SOLISTEN_LOCK(so);
xprt->xp_upcallset = 1;
solisten_upcall_set(so, svc_vc_rendezvous_soupcall, xprt);
SOLISTEN_UNLOCK(so);
return (xprt);
cleanup_svc_vc_create:
sx_destroy(&xprt->xp_lock);
svc_xprt_free(xprt);
return (NULL);
}
/*
* Create a new transport for a socket optained via soaccept().
*/
SVCXPRT *
svc_vc_create_conn(SVCPOOL *pool, struct socket *so, struct sockaddr *raddr)
{
SVCXPRT *xprt;
struct cf_conn *cd;
struct sockaddr* sa = NULL;
struct sockopt opt;
int one = 1;
int error;
bzero(&opt, sizeof(struct sockopt));
opt.sopt_dir = SOPT_SET;
opt.sopt_level = SOL_SOCKET;
opt.sopt_name = SO_KEEPALIVE;
opt.sopt_val = &one;
opt.sopt_valsize = sizeof(one);
error = sosetopt(so, &opt);
if (error) {
return (NULL);
}
if (so->so_proto->pr_protocol == IPPROTO_TCP) {
bzero(&opt, sizeof(struct sockopt));
opt.sopt_dir = SOPT_SET;
opt.sopt_level = IPPROTO_TCP;
opt.sopt_name = TCP_NODELAY;
opt.sopt_val = &one;
opt.sopt_valsize = sizeof(one);
error = sosetopt(so, &opt);
if (error) {
return (NULL);
}
}
cd = mem_alloc(sizeof(*cd));
cd->strm_stat = XPRT_IDLE;
xprt = svc_xprt_alloc();
sx_init(&xprt->xp_lock, "xprt->xp_lock");
xprt->xp_pool = pool;
xprt->xp_socket = so;
xprt->xp_p1 = cd;
xprt->xp_p2 = NULL;
xprt->xp_ops = &svc_vc_ops;
/*
* See http://www.connectathon.org/talks96/nfstcp.pdf - client
* has a 5 minute timer, server has a 6 minute timer.
*/
xprt->xp_idletimeout = 6 * 60;
memcpy(&xprt->xp_rtaddr, raddr, raddr->sa_len);
CURVNET_SET(so->so_vnet);
error = so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa);
CURVNET_RESTORE();
if (error)
goto cleanup_svc_vc_create;
memcpy(&xprt->xp_ltaddr, sa, sa->sa_len);
free(sa, M_SONAME);
xprt_register(xprt);
SOCKBUF_LOCK(&so->so_rcv);
xprt->xp_upcallset = 1;
soupcall_set(so, SO_RCV, svc_vc_soupcall, xprt);
SOCKBUF_UNLOCK(&so->so_rcv);
/*
* Throw the transport into the active list in case it already
* has some data buffered.
*/
sx_xlock(&xprt->xp_lock);
xprt_active(xprt);
sx_xunlock(&xprt->xp_lock);
return (xprt);
cleanup_svc_vc_create:
sx_destroy(&xprt->xp_lock);
svc_xprt_free(xprt);
mem_free(cd, sizeof(*cd));
return (NULL);
}
/*
* Create a new transport for a backchannel on a clnt_vc socket.
*/
SVCXPRT *
svc_vc_create_backchannel(SVCPOOL *pool)
{
SVCXPRT *xprt = NULL;
struct cf_conn *cd = NULL;
cd = mem_alloc(sizeof(*cd));
cd->strm_stat = XPRT_IDLE;
xprt = svc_xprt_alloc();
sx_init(&xprt->xp_lock, "xprt->xp_lock");
xprt->xp_pool = pool;
xprt->xp_socket = NULL;
xprt->xp_p1 = cd;
xprt->xp_p2 = NULL;
xprt->xp_ops = &svc_vc_backchannel_ops;
return (xprt);
}
/*
* This does all of the accept except the final call to soaccept. The
* caller will call soaccept after dropping its locks (soaccept may
* call malloc).
*/
int
svc_vc_accept(struct socket *head, struct socket **sop)
{
struct socket *so;
int error = 0;
short nbio;
/* XXXGL: shouldn't that be an assertion? */
if ((head->so_options & SO_ACCEPTCONN) == 0) {
error = EINVAL;
goto done;
}
#ifdef MAC
error = mac_socket_check_accept(curthread->td_ucred, head);
if (error != 0)
goto done;
#endif
/*
* XXXGL: we want non-blocking semantics. The socket could be a
* socket created by kernel as well as socket shared with userland,
* so we can't be sure about presense of SS_NBIO. We also shall not
* toggle it on the socket, since that may surprise userland. So we
* set SS_NBIO only temporarily.
*/
SOLISTEN_LOCK(head);
nbio = head->so_state & SS_NBIO;
head->so_state |= SS_NBIO;
error = solisten_dequeue(head, &so, 0);
head->so_state &= (nbio & ~SS_NBIO);
if (error)
goto done;
so->so_state |= nbio;
*sop = so;
/* connection has been removed from the listen queue */
KNOTE_UNLOCKED(&head->so_rdsel.si_note, 0);
done:
return (error);
}
/*ARGSUSED*/
static bool_t
svc_vc_rendezvous_recv(SVCXPRT *xprt, struct rpc_msg *msg,
struct sockaddr **addrp, struct mbuf **mp)
{
struct socket *so = NULL;
struct sockaddr *sa = NULL;
int error;
SVCXPRT *new_xprt;
/*
* The socket upcall calls xprt_active() which will eventually
* cause the server to call us here. We attempt to accept a
* connection from the socket and turn it into a new
* transport. If the accept fails, we have drained all pending
* connections so we call xprt_inactive().
*/
sx_xlock(&xprt->xp_lock);
error = svc_vc_accept(xprt->xp_socket, &so);
if (error == EWOULDBLOCK) {
/*
* We must re-test for new connections after taking
* the lock to protect us in the case where a new
* connection arrives after our call to accept fails
* with EWOULDBLOCK.
*/
SOLISTEN_LOCK(xprt->xp_socket);
if (TAILQ_EMPTY(&xprt->xp_socket->sol_comp))
xprt_inactive_self(xprt);
SOLISTEN_UNLOCK(xprt->xp_socket);
sx_xunlock(&xprt->xp_lock);
return (FALSE);
}
if (error) {
SOLISTEN_LOCK(xprt->xp_socket);
if (xprt->xp_upcallset) {
xprt->xp_upcallset = 0;
soupcall_clear(xprt->xp_socket, SO_RCV);
}
SOLISTEN_UNLOCK(xprt->xp_socket);
xprt_inactive_self(xprt);
sx_xunlock(&xprt->xp_lock);
return (FALSE);
}
sx_xunlock(&xprt->xp_lock);
sa = NULL;
error = soaccept(so, &sa);
if (error) {
/*
* XXX not sure if I need to call sofree or soclose here.
*/
if (sa)
free(sa, M_SONAME);
return (FALSE);
}
/*
* svc_vc_create_conn will call xprt_register - we don't need
* to do anything with the new connection except derefence it.
*/
new_xprt = svc_vc_create_conn(xprt->xp_pool, so, sa);
if (!new_xprt) {
soclose(so);
} else {
SVC_RELEASE(new_xprt);
}
free(sa, M_SONAME);
return (FALSE); /* there is never an rpc msg to be processed */
}
/*ARGSUSED*/
static enum xprt_stat
svc_vc_rendezvous_stat(SVCXPRT *xprt)
{
return (XPRT_IDLE);
}
static void
svc_vc_destroy_common(SVCXPRT *xprt)
{
if (xprt->xp_socket)
(void)soclose(xprt->xp_socket);
if (xprt->xp_netid)
(void) mem_free(xprt->xp_netid, strlen(xprt->xp_netid) + 1);
svc_xprt_free(xprt);
}
static void
svc_vc_rendezvous_destroy(SVCXPRT *xprt)
{
SOLISTEN_LOCK(xprt->xp_socket);
if (xprt->xp_upcallset) {
xprt->xp_upcallset = 0;
solisten_upcall_set(xprt->xp_socket, NULL, NULL);
}
SOLISTEN_UNLOCK(xprt->xp_socket);
svc_vc_destroy_common(xprt);
}
static void
svc_vc_destroy(SVCXPRT *xprt)
{
struct cf_conn *cd = (struct cf_conn *)xprt->xp_p1;
SOCKBUF_LOCK(&xprt->xp_socket->so_rcv);
if (xprt->xp_upcallset) {
xprt->xp_upcallset = 0;
soupcall_clear(xprt->xp_socket, SO_RCV);
}
SOCKBUF_UNLOCK(&xprt->xp_socket->so_rcv);
svc_vc_destroy_common(xprt);
if (cd->mreq)
m_freem(cd->mreq);
if (cd->mpending)
m_freem(cd->mpending);
mem_free(cd, sizeof(*cd));
}
static void
svc_vc_backchannel_destroy(SVCXPRT *xprt)
{
struct cf_conn *cd = (struct cf_conn *)xprt->xp_p1;
struct mbuf *m, *m2;
svc_xprt_free(xprt);
m = cd->mreq;
while (m != NULL) {
m2 = m;
m = m->m_nextpkt;
m_freem(m2);
}
mem_free(cd, sizeof(*cd));
}
/*ARGSUSED*/
static bool_t
svc_vc_control(SVCXPRT *xprt, const u_int rq, void *in)
{
return (FALSE);
}
static bool_t
svc_vc_rendezvous_control(SVCXPRT *xprt, const u_int rq, void *in)
{
return (FALSE);
}
static bool_t
svc_vc_backchannel_control(SVCXPRT *xprt, const u_int rq, void *in)
{
return (FALSE);
}
static enum xprt_stat
svc_vc_stat(SVCXPRT *xprt)
{
struct cf_conn *cd;
cd = (struct cf_conn *)(xprt->xp_p1);
if (cd->strm_stat == XPRT_DIED)
return (XPRT_DIED);
if (cd->mreq != NULL && cd->resid == 0 && cd->eor)
return (XPRT_MOREREQS);
if (soreadable(xprt->xp_socket))
return (XPRT_MOREREQS);
return (XPRT_IDLE);
}
static bool_t
svc_vc_ack(SVCXPRT *xprt, uint32_t *ack)
{
*ack = atomic_load_acq_32(&xprt->xp_snt_cnt);
*ack -= sbused(&xprt->xp_socket->so_snd);
return (TRUE);
}
static enum xprt_stat
svc_vc_backchannel_stat(SVCXPRT *xprt)
{
struct cf_conn *cd;
cd = (struct cf_conn *)(xprt->xp_p1);
if (cd->mreq != NULL)
return (XPRT_MOREREQS);
return (XPRT_IDLE);
}
/*
* If we have an mbuf chain in cd->mpending, try to parse a record from it,
* leaving the result in cd->mreq. If we don't have a complete record, leave
* the partial result in cd->mreq and try to read more from the socket.
*/
static int
svc_vc_process_pending(SVCXPRT *xprt)
{
struct cf_conn *cd = (struct cf_conn *) xprt->xp_p1;
struct socket *so = xprt->xp_socket;
struct mbuf *m;
/*
* If cd->resid is non-zero, we have part of the
* record already, otherwise we are expecting a record
* marker.
*/
if (!cd->resid && cd->mpending) {
/*
* See if there is enough data buffered to
* make up a record marker. Make sure we can
* handle the case where the record marker is
* split across more than one mbuf.
*/
size_t n = 0;
uint32_t header;
m = cd->mpending;
while (n < sizeof(uint32_t) && m) {
n += m->m_len;
m = m->m_next;
}
if (n < sizeof(uint32_t)) {
so->so_rcv.sb_lowat = sizeof(uint32_t) - n;
return (FALSE);
}
m_copydata(cd->mpending, 0, sizeof(header),
(char *)&header);
header = ntohl(header);
cd->eor = (header & 0x80000000) != 0;
cd->resid = header & 0x7fffffff;
m_adj(cd->mpending, sizeof(uint32_t));
}
/*
* Start pulling off mbufs from cd->mpending
* until we either have a complete record or
* we run out of data. We use m_split to pull
* data - it will pull as much as possible and
* split the last mbuf if necessary.
*/
while (cd->mpending && cd->resid) {
m = cd->mpending;
if (cd->mpending->m_next
|| cd->mpending->m_len > cd->resid)
cd->mpending = m_split(cd->mpending,
cd->resid, M_WAITOK);
else
cd->mpending = NULL;
if (cd->mreq)
m_last(cd->mreq)->m_next = m;
else
cd->mreq = m;
while (m) {
cd->resid -= m->m_len;
m = m->m_next;
}
}
/*
* Block receive upcalls if we have more data pending,
* otherwise report our need.
*/
if (cd->mpending)
so->so_rcv.sb_lowat = INT_MAX;
else
so->so_rcv.sb_lowat =
imax(1, imin(cd->resid, so->so_rcv.sb_hiwat / 2));
return (TRUE);
}
static bool_t
svc_vc_recv(SVCXPRT *xprt, struct rpc_msg *msg,
struct sockaddr **addrp, struct mbuf **mp)
{
struct cf_conn *cd = (struct cf_conn *) xprt->xp_p1;
struct uio uio;
struct mbuf *m;
struct socket* so = xprt->xp_socket;
XDR xdrs;
int error, rcvflag;
uint32_t xid_plus_direction[2];
/*
* Serialise access to the socket and our own record parsing
* state.
*/
sx_xlock(&xprt->xp_lock);
for (;;) {
/* If we have no request ready, check pending queue. */
while (cd->mpending &&
(cd->mreq == NULL || cd->resid != 0 || !cd->eor)) {
if (!svc_vc_process_pending(xprt))
break;
}
/* Process and return complete request in cd->mreq. */
if (cd->mreq != NULL && cd->resid == 0 && cd->eor) {
/*
* Now, check for a backchannel reply.
* The XID is in the first uint32_t of the reply
* and the message direction is the second one.
*/
if ((cd->mreq->m_len >= sizeof(xid_plus_direction) ||
m_length(cd->mreq, NULL) >=
sizeof(xid_plus_direction)) &&
xprt->xp_p2 != NULL) {
m_copydata(cd->mreq, 0,
sizeof(xid_plus_direction),
(char *)xid_plus_direction);
xid_plus_direction[0] =
ntohl(xid_plus_direction[0]);
xid_plus_direction[1] =
ntohl(xid_plus_direction[1]);
/* Check message direction. */
if (xid_plus_direction[1] == REPLY) {
clnt_bck_svccall(xprt->xp_p2,
cd->mreq,
xid_plus_direction[0]);
cd->mreq = NULL;
continue;
}
}
xdrmbuf_create(&xdrs, cd->mreq, XDR_DECODE);
cd->mreq = NULL;
/* Check for next request in a pending queue. */
svc_vc_process_pending(xprt);
if (cd->mreq == NULL || cd->resid != 0) {
SOCKBUF_LOCK(&so->so_rcv);
if (!soreadable(so))
xprt_inactive_self(xprt);
SOCKBUF_UNLOCK(&so->so_rcv);
}
sx_xunlock(&xprt->xp_lock);
if (! xdr_callmsg(&xdrs, msg)) {
XDR_DESTROY(&xdrs);
return (FALSE);
}
*addrp = NULL;
*mp = xdrmbuf_getall(&xdrs);
XDR_DESTROY(&xdrs);
return (TRUE);
}
/*
* The socket upcall calls xprt_active() which will eventually
* cause the server to call us here. We attempt to
* read as much as possible from the socket and put
* the result in cd->mpending. If the read fails,
* we have drained both cd->mpending and the socket so
* we can call xprt_inactive().
*/
uio.uio_resid = 1000000000;
uio.uio_td = curthread;
m = NULL;
rcvflag = MSG_DONTWAIT;
error = soreceive(so, NULL, &uio, &m, NULL, &rcvflag);
if (error == EWOULDBLOCK) {
/*
* We must re-test for readability after
* taking the lock to protect us in the case
* where a new packet arrives on the socket
* after our call to soreceive fails with
* EWOULDBLOCK.
*/
SOCKBUF_LOCK(&so->so_rcv);
if (!soreadable(so))
xprt_inactive_self(xprt);
SOCKBUF_UNLOCK(&so->so_rcv);
sx_xunlock(&xprt->xp_lock);
return (FALSE);
}
if (error) {
SOCKBUF_LOCK(&so->so_rcv);
if (xprt->xp_upcallset) {
xprt->xp_upcallset = 0;
soupcall_clear(so, SO_RCV);
}
SOCKBUF_UNLOCK(&so->so_rcv);
xprt_inactive_self(xprt);
cd->strm_stat = XPRT_DIED;
sx_xunlock(&xprt->xp_lock);
return (FALSE);
}
if (!m) {
/*
* EOF - the other end has closed the socket.
*/
xprt_inactive_self(xprt);
cd->strm_stat = XPRT_DIED;
sx_xunlock(&xprt->xp_lock);
return (FALSE);
}
if (cd->mpending)
m_last(cd->mpending)->m_next = m;
else
cd->mpending = m;
}
}
static bool_t
svc_vc_backchannel_recv(SVCXPRT *xprt, struct rpc_msg *msg,
struct sockaddr **addrp, struct mbuf **mp)
{
struct cf_conn *cd = (struct cf_conn *) xprt->xp_p1;
struct ct_data *ct;
struct mbuf *m;
XDR xdrs;
sx_xlock(&xprt->xp_lock);
ct = (struct ct_data *)xprt->xp_p2;
if (ct == NULL) {
sx_xunlock(&xprt->xp_lock);
return (FALSE);
}
mtx_lock(&ct->ct_lock);
m = cd->mreq;
if (m == NULL) {
xprt_inactive_self(xprt);
mtx_unlock(&ct->ct_lock);
sx_xunlock(&xprt->xp_lock);
return (FALSE);
}
cd->mreq = m->m_nextpkt;
mtx_unlock(&ct->ct_lock);
sx_xunlock(&xprt->xp_lock);
xdrmbuf_create(&xdrs, m, XDR_DECODE);
if (! xdr_callmsg(&xdrs, msg)) {
XDR_DESTROY(&xdrs);
return (FALSE);
}
*addrp = NULL;
*mp = xdrmbuf_getall(&xdrs);
XDR_DESTROY(&xdrs);
return (TRUE);
}
static bool_t
svc_vc_reply(SVCXPRT *xprt, struct rpc_msg *msg,
struct sockaddr *addr, struct mbuf *m, uint32_t *seq)
{
XDR xdrs;
struct mbuf *mrep;
bool_t stat = TRUE;
int error, len;
/*
* Leave space for record mark.
*/
mrep = m_gethdr(M_WAITOK, MT_DATA);
mrep->m_data += sizeof(uint32_t);
xdrmbuf_create(&xdrs, mrep, XDR_ENCODE);
if (msg->rm_reply.rp_stat == MSG_ACCEPTED &&
msg->rm_reply.rp_acpt.ar_stat == SUCCESS) {
if (!xdr_replymsg(&xdrs, msg))
stat = FALSE;
else
xdrmbuf_append(&xdrs, m);
} else {
stat = xdr_replymsg(&xdrs, msg);
}
if (stat) {
m_fixhdr(mrep);
/*
* Prepend a record marker containing the reply length.
*/
M_PREPEND(mrep, sizeof(uint32_t), M_WAITOK);
len = mrep->m_pkthdr.len;
*mtod(mrep, uint32_t *) =
htonl(0x80000000 | (len - sizeof(uint32_t)));
atomic_add_32(&xprt->xp_snd_cnt, len);
error = sosend(xprt->xp_socket, NULL, NULL, mrep, NULL,
0, curthread);
if (!error) {
atomic_add_rel_32(&xprt->xp_snt_cnt, len);
if (seq)
*seq = xprt->xp_snd_cnt;
stat = TRUE;
} else
atomic_subtract_32(&xprt->xp_snd_cnt, len);
} else {
m_freem(mrep);
}
XDR_DESTROY(&xdrs);
return (stat);
}
static bool_t
svc_vc_backchannel_reply(SVCXPRT *xprt, struct rpc_msg *msg,
struct sockaddr *addr, struct mbuf *m, uint32_t *seq)
{
struct ct_data *ct;
XDR xdrs;
struct mbuf *mrep;
bool_t stat = TRUE;
int error;
/*
* Leave space for record mark.
*/
mrep = m_gethdr(M_WAITOK, MT_DATA);
mrep->m_data += sizeof(uint32_t);
xdrmbuf_create(&xdrs, mrep, XDR_ENCODE);
if (msg->rm_reply.rp_stat == MSG_ACCEPTED &&
msg->rm_reply.rp_acpt.ar_stat == SUCCESS) {
if (!xdr_replymsg(&xdrs, msg))
stat = FALSE;
else
xdrmbuf_append(&xdrs, m);
} else {
stat = xdr_replymsg(&xdrs, msg);
}
if (stat) {
m_fixhdr(mrep);
/*
* Prepend a record marker containing the reply length.
*/
M_PREPEND(mrep, sizeof(uint32_t), M_WAITOK);
*mtod(mrep, uint32_t *) =
htonl(0x80000000 | (mrep->m_pkthdr.len
- sizeof(uint32_t)));
sx_xlock(&xprt->xp_lock);
ct = (struct ct_data *)xprt->xp_p2;
if (ct != NULL)
error = sosend(ct->ct_socket, NULL, NULL, mrep, NULL,
0, curthread);
else
error = EPIPE;
sx_xunlock(&xprt->xp_lock);
if (!error) {
stat = TRUE;
}
} else {
m_freem(mrep);
}
XDR_DESTROY(&xdrs);
return (stat);
}
static bool_t
svc_vc_null()
{
return (FALSE);
}
static int
svc_vc_soupcall(struct socket *so, void *arg, int waitflag)
{
SVCXPRT *xprt = (SVCXPRT *) arg;
if (soreadable(xprt->xp_socket))
xprt_active(xprt);
return (SU_OK);
}
static int
svc_vc_rendezvous_soupcall(struct socket *head, void *arg, int waitflag)
{
SVCXPRT *xprt = (SVCXPRT *) arg;
if (!TAILQ_EMPTY(&head->sol_comp))
xprt_active(xprt);
return (SU_OK);
}
#if 0
/*
* Get the effective UID of the sending process. Used by rpcbind, keyserv
* and rpc.yppasswdd on AF_LOCAL.
*/
int
__rpc_get_local_uid(SVCXPRT *transp, uid_t *uid) {
int sock, ret;
gid_t egid;
uid_t euid;
struct sockaddr *sa;
sock = transp->xp_fd;
sa = (struct sockaddr *)transp->xp_rtaddr;
if (sa->sa_family == AF_LOCAL) {
ret = getpeereid(sock, &euid, &egid);
if (ret == 0)
*uid = euid;
return (ret);
} else
return (-1);
}
#endif
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