svc_vc.c

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/*
 * 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.
 */

//#include <sys/cdefs.h>

/*
 * 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 <wintirpc.h>
//#include <pthread.h>
#include <reentrant.h>
//#include <sys/socket.h>
#include <sys/types.h>
//#include <sys/param.h>
//#include <sys/poll.h>
//#include <sys/un.h>
//#include <sys/time.h>
//#include <sys/uio.h>
//#include <netinet/in.h>
//#include <netinet/tcp.h>

#include <assert.h>
//#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
//#include <unistd.h>

#include <rpc/rpc.h>

#include "rpc_com.h"

#include <getpeereid.h>


extern rwlock_t svc_fd_lock;

static SVCXPRT *makefd_xprt(SOCKET, u_int, u_int);
static bool_t rendezvous_request(SVCXPRT *, struct rpc_msg *);
static enum xprt_stat rendezvous_stat(SVCXPRT *);
static void svc_vc_destroy(SVCXPRT *);
static void __svc_vc_dodestroy (SVCXPRT *);
static int read_vc(void *, void *, int);
static int write_vc(void *, void *, int);
static enum xprt_stat svc_vc_stat(SVCXPRT *);
static bool_t svc_vc_recv(SVCXPRT *, struct rpc_msg *);
static bool_t svc_vc_getargs(SVCXPRT *, xdrproc_t, void *);
static bool_t svc_vc_freeargs(SVCXPRT *, xdrproc_t, void *);
static bool_t svc_vc_reply(SVCXPRT *, struct rpc_msg *);
static void svc_vc_rendezvous_ops(SVCXPRT *);
static void svc_vc_ops(SVCXPRT *);
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);

struct cf_rendezvous { /* kept in xprt->xp_p1 for rendezvouser */
    u_int sendsize;
    u_int recvsize;
    int maxrec;
};

struct cf_conn {  /* kept in xprt->xp_p1 for actual connection */
    enum xprt_stat strm_stat;
    u_int32_t x_id;
    XDR xdrs;
    char verf_body[MAX_AUTH_BYTES];
    u_int sendsize;
    u_int recvsize;
    int maxrec;
    bool_t nonblock;
    struct timeval last_recv_time;
};

/*
 * This is used to set xprt->xp_raddr in a way legacy
 * apps can deal with
 */
void
__xprt_set_raddr(SVCXPRT *xprt, const struct sockaddr_storage *ss)
{
    switch (ss->ss_family) {
    case AF_INET6:
        memcpy(&xprt->xp_raddr, ss, sizeof(struct sockaddr_in6));
        xprt->xp_addrlen = sizeof (struct sockaddr_in6);
        break;
    case AF_INET:
        memcpy(&xprt->xp_raddr, ss, sizeof(struct sockaddr_in));
        xprt->xp_addrlen = sizeof (struct sockaddr_in);
        break;
    default:
        xprt->xp_raddr.sin6_family = AF_UNSPEC;
        xprt->xp_addrlen = sizeof (struct sockaddr);
        break;
    }
}

/*
 * 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(fd, sendsize, recvsize)
    int fd;
    u_int sendsize;
    u_int recvsize;
{
    SVCXPRT *xprt;
    struct cf_rendezvous *r = NULL;
    struct __rpc_sockinfo si;
    struct sockaddr_storage sslocal;
    socklen_t slen;

    r = mem_alloc(sizeof(*r));
    if (r == NULL) {
        // XXX warnx("svc_vc_create: out of memory");
        goto cleanup_svc_vc_create;
    }
    if (!__rpc_fd2sockinfo(fd, &si))
        return NULL;
    r->sendsize = __rpc_get_t_size(si.si_af, si.si_proto, (int)sendsize);
    r->recvsize = __rpc_get_t_size(si.si_af, si.si_proto, (int)recvsize);
    r->maxrec = __svc_maxrec;
    xprt = mem_alloc(sizeof(SVCXPRT));
    if (xprt == NULL) {
        // XXX warnx("svc_vc_create: out of memory");
        goto cleanup_svc_vc_create;
    }
    xprt->xp_tp = NULL;
    xprt->xp_p1 = r;
    xprt->xp_p2 = NULL;
    xprt->xp_p3 = NULL;
    xprt->xp_verf = _null_auth;
    svc_vc_rendezvous_ops(xprt);
    xprt->xp_port = (u_short)-1;    /* It is the rendezvouser */
    xprt->xp_fd = fd;

    slen = sizeof (struct sockaddr_storage);
    if (getsockname(fd, (struct sockaddr *)(void *)&sslocal, &slen) == SOCKET_ERROR) {
        // XXX warnx("svc_vc_create: could not retrieve local addr");
        goto cleanup_svc_vc_create;
    }

    if (!__rpc_set_netbuf(&xprt->xp_ltaddr, &sslocal, sizeof(sslocal))) {
        // XXX warnx("svc_vc_create: no mem for local addr");
        goto cleanup_svc_vc_create;
    }
    xprt_register(xprt);
    return (xprt);
cleanup_svc_vc_create:
    if (r != NULL)
        mem_free(r, sizeof(*r));
    return (NULL);
}

/*
 * Like svtcp_create(), except the routine takes any *open* UNIX file
 * descriptor as its first input.
 */
SVCXPRT *
svc_fd_create(fd, sendsize, recvsize)
    SOCKET fd;
    u_int sendsize;
    u_int recvsize;
{
    struct sockaddr_storage ss;
    socklen_t slen;
    SVCXPRT *ret;

    assert(fd != -1);

    ret = makefd_xprt(fd, sendsize, recvsize);
    if (ret == NULL)
        return NULL;

    slen = sizeof (struct sockaddr_storage);
    if (getsockname(fd, (struct sockaddr *)(void *)&ss, &slen) == SOCKET_ERROR) {
        // XXX warnx("svc_fd_create: could not retrieve local addr");
        goto freedata;
    }
    if (!__rpc_set_netbuf(&ret->xp_ltaddr, &ss, sizeof(ss))) {
        // XXX warnx("svc_fd_create: no mem for local addr");
        goto freedata;
    }

    slen = sizeof (struct sockaddr_storage);
    if (getpeername(fd, (struct sockaddr *)(void *)&ss, &slen) == SOCKET_ERROR) {
        // XXX warnx("svc_fd_create: could not retrieve remote addr");
        goto freedata;
    }
    if (!__rpc_set_netbuf(&ret->xp_rtaddr, &ss, sizeof(ss))) {
        // XXX warnx("svc_fd_create: no mem for local addr");
        goto freedata;
    }

    /* Set xp_raddr for compatibility */
    __xprt_set_raddr(ret, &ss);

    return ret;

freedata:
    if (ret->xp_ltaddr.buf != NULL)
        mem_free(ret->xp_ltaddr.buf, rep->xp_ltaddr.maxlen);

    return NULL;
}

static SVCXPRT *
makefd_xprt(fd, sendsize, recvsize)
    SOCKET fd;
    u_int sendsize;
    u_int recvsize;
{
    SVCXPRT *xprt;
    struct cf_conn *cd;
    const char *netid;
    struct __rpc_sockinfo si;
 
    assert(fd != SOCKET_ERROR);

        if (fd >= FD_SETSIZE) {
                // XXX warnx("svc_vc: makefd_xprt: fd too high\n");
                xprt = NULL;
                goto done;
        }

    xprt = mem_alloc(sizeof(SVCXPRT));
    if (xprt == NULL) {
        // XXX warnx("svc_vc: makefd_xprt: out of memory");
        goto done;
    }
    memset(xprt, 0, sizeof *xprt);
    cd = mem_alloc(sizeof(struct cf_conn));
    if (cd == NULL) {
        // XXX warnx("svc_tcp: makefd_xprt: out of memory");
        mem_free(xprt, sizeof(SVCXPRT));
        xprt = NULL;
        goto done;
    }
    cd->strm_stat = XPRT_IDLE;
    xdrrec_create(&(cd->xdrs), sendsize, recvsize,
        xprt, read_vc, write_vc);
    xprt->xp_p1 = cd;
    xprt->xp_verf.oa_base = cd->verf_body;
    svc_vc_ops(xprt);  /* truely deals with calls */
    xprt->xp_port = 0;  /* this is a connection, not a rendezvouser */
    xprt->xp_fd = fd;
        if (__rpc_fd2sockinfo(fd, &si) && __rpc_sockinfo2netid(&si, &netid))
        xprt->xp_netid = strdup(netid);

    xprt_register(xprt);
done:
    return (xprt);
}

/*ARGSUSED*/
static bool_t
rendezvous_request(xprt, msg)
    SVCXPRT *xprt;
    struct rpc_msg *msg;
{
    SOCKET sock;
#ifndef _WIN32
    int flags;
#endif
    struct cf_rendezvous *r;
    struct cf_conn *cd;
    struct sockaddr_storage addr;
    socklen_t len;
    struct __rpc_sockinfo si;
    SVCXPRT *newxprt;
    fd_set cleanfds;

    assert(xprt != NULL);
    assert(msg != NULL);

    r = (struct cf_rendezvous *)xprt->xp_p1;
again:
    len = sizeof addr;
    if ((sock = accept(xprt->xp_fd, (struct sockaddr *)(void *)&addr,
        &len)) == SOCKET_ERROR) {
        if (errno == EINTR)
            goto again;
#ifndef __REACTOS__ // CVE-2018-14621
        /*
         * Clean out the most idle file descriptor when we're
         * running out.
         */
        if (errno == EMFILE || errno == ENFILE) {
            cleanfds = svc_fdset;
            __svc_clean_idle(&cleanfds, 0, FALSE);
            goto again;
        }
#endif
        return (FALSE);
    }
    /*
     * make a new transporter (re-uses xprt)
     */

    newxprt = makefd_xprt(sock, r->sendsize, r->recvsize);
#ifdef __REACTOS__ // CVE-2018-14622
    if (!newxprt)
        return (FALSE);
#endif

    if (!__rpc_set_netbuf(&newxprt->xp_rtaddr, &addr, len))
        return (FALSE);

    __xprt_set_raddr(newxprt, &addr);

    if (__rpc_fd2sockinfo(sock, &si) && si.si_proto == IPPROTO_TCP) {
        len = 1;
        /* XXX fvdl - is this useful? */
        setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, (const char *)&len, sizeof (len));
    }

    cd = (struct cf_conn *)newxprt->xp_p1;

    cd->recvsize = r->recvsize;
    cd->sendsize = r->sendsize;
    cd->maxrec = r->maxrec;

#ifndef _WIN32
    if (cd->maxrec != 0) {
        flags = fcntl(sock, F_GETFL, 0);
        if (flags  == -1)
            return (FALSE);
        if (fcntl(sock, F_SETFL, flags | O_NONBLOCK) == -1)
            return (FALSE);
        if (cd->recvsize > cd->maxrec)
            cd->recvsize = cd->maxrec;
        cd->nonblock = TRUE;
        __xdrrec_setnonblock(&cd->xdrs, cd->maxrec);
    } else
        cd->nonblock = FALSE;
#endif  /* _WIN32 */

    gettimeofday(&cd->last_recv_time, NULL);

    return (FALSE); /* there is never an rpc msg to be processed */
}

/*ARGSUSED*/
static enum xprt_stat
rendezvous_stat(xprt)
    SVCXPRT *xprt;
{

    return (XPRT_IDLE);
}

static void
svc_vc_destroy(xprt)
    SVCXPRT *xprt;
{
    assert(xprt != NULL);
    
    xprt_unregister(xprt);
    __svc_vc_dodestroy(xprt);
}

static void
__svc_vc_dodestroy(xprt)
    SVCXPRT *xprt;
{
    struct cf_conn *cd;
    struct cf_rendezvous *r;

    cd = (struct cf_conn *)xprt->xp_p1;

    if (xprt->xp_fd != RPC_ANYFD)
        (void)closesocket(xprt->xp_fd);
    if (xprt->xp_port != 0) {
        /* a rendezvouser socket */
        r = (struct cf_rendezvous *)xprt->xp_p1;
        mem_free(r, sizeof (struct cf_rendezvous));
        xprt->xp_port = 0;
    } else {
        /* an actual connection socket */
        XDR_DESTROY(&(cd->xdrs));
        mem_free(cd, sizeof(struct cf_conn));
    }
    if (xprt->xp_rtaddr.buf)
        mem_free(xprt->xp_rtaddr.buf, xprt->xp_rtaddr.maxlen);
    if (xprt->xp_ltaddr.buf)
        mem_free(xprt->xp_ltaddr.buf, xprt->xp_ltaddr.maxlen);
    if (xprt->xp_tp)
        free(xprt->xp_tp);
    if (xprt->xp_netid)
        free(xprt->xp_netid);
    mem_free(xprt, sizeof(SVCXPRT));
}

/*ARGSUSED*/
static bool_t
svc_vc_control(xprt, rq, in)
    SVCXPRT *xprt;
    const u_int rq;
    void *in;
{
    return (FALSE);
}

static bool_t
svc_vc_rendezvous_control(xprt, rq, in)
    SVCXPRT *xprt;
    const u_int rq;
    void *in;
{
    struct cf_rendezvous *cfp;

    cfp = (struct cf_rendezvous *)xprt->xp_p1;
    if (cfp == NULL)
        return (FALSE);
    switch (rq) {
        case SVCGET_CONNMAXREC:
            *(int *)in = cfp->maxrec;
            break;
        case SVCSET_CONNMAXREC:
            cfp->maxrec = *(int *)in;
            break;
        default:
            return (FALSE);
    }
    return (TRUE);
}

/*
 * reads data from the tcp or uip connection.
 * any error is fatal and the connection is closed.
 * (And a read of zero bytes is a half closed stream => error.)
 * All read operations timeout after 35 seconds.  A timeout is
 * fatal for the connection.
 */
static int
read_vc(xprtp, buf, len)
    void *xprtp;
    void *buf;
    int len;
{
    SVCXPRT *xprt;
    SOCKET sock;
    int milliseconds = 35 * 1000;
    struct pollfd pollfd;
    struct cf_conn *cfp;

    xprt = (SVCXPRT *)xprtp;
    assert(xprt != NULL);

    sock = xprt->xp_fd;

    cfp = (struct cf_conn *)xprt->xp_p1;

    if (cfp->nonblock) {
#ifdef _WIN32
        len = recv(sock, buf, (size_t)len, 0);
#else
        len = read(sock, buf, (size_t)len);
#endif
        if (len == SOCKET_ERROR) {
            if (WSAGetLastError() == EAGAIN)
                len = 0;
            else
                goto fatal_err;
        }
        if (len != 0)
            gettimeofday(&cfp->last_recv_time, NULL);
        return len;
    }

    do {
#ifndef __REACTOS__
        pollfd.fd = sock;
        pollfd.events = POLLIN;
        pollfd.revents = 0;
        switch (poll(&pollfd, 1, milliseconds)) {
#else
        /* ReactOS: use select instead of poll */
        fd_set infd;
        struct timeval timeout;

        FD_ZERO(&infd);
        FD_SET(sock, &infd);

        timeout.tv_sec = 0;
        timeout.tv_usec = milliseconds * 1000;

        switch (select(0, &infd, NULL, NULL, &timeout)) {
#endif
        case -1:
            if (errno == EINTR)
                continue;
            /*FALLTHROUGH*/
        case 0:
            goto fatal_err;

        default:
            break;
        }
#ifndef __REACTOS__
    } while ((pollfd.revents & POLLIN) == 0);
#else
    } while (TRUE);
#endif

#ifdef _WIN32
    if ((len = recv(sock, buf, (size_t)len, 0)) > 0) {
#else
    if ((len = read(sock, buf, (size_t)len)) > 0) {
#endif
        gettimeofday(&cfp->last_recv_time, NULL);
        return (len);
    }

fatal_err:
    ((struct cf_conn *)(xprt->xp_p1))->strm_stat = XPRT_DIED;
    return (-1);
}

/*
 * writes data to the tcp connection.
 * Any error is fatal and the connection is closed.
 */
static int
#ifdef __REACTOS__
write_vc(xprtp, ptr, len)
#else
write_vc(xprtp, buf, len)
#endif
    void *xprtp;
#ifdef __REACTOS__
    void *ptr;
#else
    char *buf;
#endif
    int len;
{
    SVCXPRT *xprt;
    int i, cnt;
    struct cf_conn *cd;
    struct timeval tv0, tv1;
#ifdef __REACTOS__
    char *buf = ptr;
#endif

    xprt = (SVCXPRT *)xprtp;
    assert(xprt != NULL);

    cd = (struct cf_conn *)xprt->xp_p1;

    if (cd->nonblock)
        gettimeofday(&tv0, NULL);
    
    for (cnt = len; cnt > 0; cnt -= i, buf += i) {
#ifdef _WIN32
        i = send(xprt->xp_fd, buf, (size_t)cnt, 0);
#else
        i = write(xprt->xp_fd, buf, (size_t)cnt);
#endif
        if (i == SOCKET_ERROR) {
            if (WSAGetLastError() != EAGAIN || !cd->nonblock) {
                cd->strm_stat = XPRT_DIED;
                return (-1);
            }
            if (cd->nonblock && i != cnt) {
                /*
                 * For non-blocking connections, do not
                 * take more than 2 seconds writing the
                 * data out.
                 *
                 * XXX 2 is an arbitrary amount.
                 */
                gettimeofday(&tv1, NULL);
                if (tv1.tv_sec - tv0.tv_sec >= 2) {
                    cd->strm_stat = XPRT_DIED;
                    return (-1);
                }
            }
        }
    }

    return (len);
}

static enum xprt_stat
svc_vc_stat(xprt)
    SVCXPRT *xprt;
{
    struct cf_conn *cd;

    assert(xprt != NULL);

    cd = (struct cf_conn *)(xprt->xp_p1);

    if (cd->strm_stat == XPRT_DIED)
        return (XPRT_DIED);
    if (! xdrrec_eof(&(cd->xdrs)))
        return (XPRT_MOREREQS);
    return (XPRT_IDLE);
}

static bool_t
svc_vc_recv(xprt, msg)
    SVCXPRT *xprt;
    struct rpc_msg *msg;
{
    struct cf_conn *cd;
    XDR *xdrs;

    assert(xprt != NULL);
    assert(msg != NULL);

    cd = (struct cf_conn *)(xprt->xp_p1);
    xdrs = &(cd->xdrs);

    if (cd->nonblock) {
        if (!__xdrrec_getrec(xdrs, &cd->strm_stat, TRUE))
            return FALSE;
    }

    xdrs->x_op = XDR_DECODE;
    (void)xdrrec_skiprecord(xdrs);
    if (xdr_callmsg(xdrs, msg)) {
        cd->x_id = msg->rm_xid;
        return (TRUE);
    }
    cd->strm_stat = XPRT_DIED;
    return (FALSE);
}

static bool_t
svc_vc_getargs(xprt, xdr_args, args_ptr)
    SVCXPRT *xprt;
    xdrproc_t xdr_args;
    void *args_ptr;
{

    assert(xprt != NULL);
    /* args_ptr may be NULL */
    return ((*xdr_args)(&(((struct cf_conn *)(xprt->xp_p1))->xdrs),
        args_ptr));
}

static bool_t
svc_vc_freeargs(xprt, xdr_args, args_ptr)
    SVCXPRT *xprt;
    xdrproc_t xdr_args;
    void *args_ptr;
{
    XDR *xdrs;

    assert(xprt != NULL);
    /* args_ptr may be NULL */

    xdrs = &(((struct cf_conn *)(xprt->xp_p1))->xdrs);

    xdrs->x_op = XDR_FREE;
    return ((*xdr_args)(xdrs, args_ptr));
}

static bool_t
svc_vc_reply(xprt, msg)
    SVCXPRT *xprt;
    struct rpc_msg *msg;
{
    struct cf_conn *cd;
    XDR *xdrs;
    bool_t rstat;

    assert(xprt != NULL);
    assert(msg != NULL);

    cd = (struct cf_conn *)(xprt->xp_p1);
    xdrs = &(cd->xdrs);

    xdrs->x_op = XDR_ENCODE;
    msg->rm_xid = cd->x_id;
    rstat = xdr_replymsg(xdrs, msg);
    (void)xdrrec_endofrecord(xdrs, TRUE);
    return (rstat);
}

static void
svc_vc_ops(xprt)
    SVCXPRT *xprt;
{
    static struct xp_ops ops;
    static struct xp_ops2 ops2;
    extern mutex_t ops_lock;

/* VARIABLES PROTECTED BY ops_lock: ops, ops2 */

    mutex_lock(&ops_lock);
    if (ops.xp_recv == NULL) {
        ops.xp_recv = svc_vc_recv;
        ops.xp_stat = svc_vc_stat;
        ops.xp_getargs = svc_vc_getargs;
        ops.xp_reply = svc_vc_reply;
        ops.xp_freeargs = svc_vc_freeargs;
        ops.xp_destroy = svc_vc_destroy;
        ops2.xp_control = svc_vc_control;
    }
    xprt->xp_ops = &ops;
    xprt->xp_ops2 = &ops2;
    mutex_unlock(&ops_lock);
}

static void
svc_vc_rendezvous_ops(xprt)
    SVCXPRT *xprt;
{
    static struct xp_ops ops;
    static struct xp_ops2 ops2;
    extern mutex_t ops_lock;

    mutex_lock(&ops_lock);
    if (ops.xp_recv == NULL) {
        ops.xp_recv = rendezvous_request;
        ops.xp_stat = rendezvous_stat;
        ops.xp_getargs =
            (bool_t (*)(SVCXPRT *, xdrproc_t, void *))abort;
        ops.xp_reply =
            (bool_t (*)(SVCXPRT *, struct rpc_msg *))abort;
        ops.xp_freeargs =
            (bool_t (*)(SVCXPRT *, xdrproc_t, void *))abort,
        ops.xp_destroy = svc_vc_destroy;
        ops2.xp_control = svc_vc_rendezvous_control;
    }
    xprt->xp_ops = &ops;
    xprt->xp_ops2 = &ops2;
    mutex_unlock(&ops_lock);
}

/*
 * 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) {
    SOCKET sock;
    int ret;
    gid_t egid;
    uid_t euid;
    struct sockaddr *sa;

    sock = transp->xp_fd;
    sa = (struct sockaddr *)transp->xp_rtaddr.buf;
    if (sa->sa_family == AF_UNIX) {
        ret = getpeereid(sock, &euid, &egid);
        if (ret == 0)
            *uid = euid;
        return (ret);
    } else
        return (-1);
}

#ifdef _WIN32
void timersub( const struct timeval *tvp, const struct timeval *uvp, struct timeval *vvp ) 
{ 
    vvp->tv_sec = tvp->tv_sec - uvp->tv_sec; 
    vvp->tv_usec = tvp->tv_usec - uvp->tv_usec; 
    if( vvp->tv_usec < 0 ) 
    { 
       --vvp->tv_sec; 
       vvp->tv_usec += 1000000; 
    } 
} 
#endif

/*
 * Destroy xprts that have not have had any activity in 'timeout' seconds.
 * If 'cleanblock' is true, blocking connections (the default) are also
 * cleaned. If timeout is 0, the least active connection is picked.
 */
bool_t
__svc_clean_idle(fd_set *fds, int timeout, bool_t cleanblock)
{
    int i, ncleaned;
    SVCXPRT *xprt, *least_active;
    struct timeval tv, tdiff, tmax;
    struct cf_conn *cd;

    gettimeofday(&tv, NULL);
    tmax.tv_sec = tmax.tv_usec = 0;
    least_active = NULL;
    rwlock_wrlock(&svc_fd_lock);
    for (i = ncleaned = 0; i <= svc_maxfd; i++) {
        if (FD_ISSET(i, fds)) {
            xprt = __svc_xports[i];
            if (xprt == NULL || xprt->xp_ops == NULL ||
                xprt->xp_ops->xp_recv != svc_vc_recv)
                continue;
            cd = (struct cf_conn *)xprt->xp_p1;
            if (!cleanblock && !cd->nonblock)
                continue;
            if (timeout == 0) {
                timersub(&tv, &cd->last_recv_time, &tdiff);
                if (timercmp(&tdiff, &tmax, >)) {
                    tmax = tdiff;
                    least_active = xprt;
                }
                continue;
            }
            if (tv.tv_sec - cd->last_recv_time.tv_sec > timeout) {
                __xprt_unregister_unlocked(xprt);
                __svc_vc_dodestroy(xprt);
                ncleaned++;
            }
        }
    }
    if (timeout == 0 && least_active != NULL) {
        __xprt_unregister_unlocked(least_active);
        __svc_vc_dodestroy(least_active);
        ncleaned++;
    }
    rwlock_unlock(&svc_fd_lock);
    return ncleaned > 0 ? TRUE : FALSE;
}