usr/src/new/sunrpc/clnt_udp.c

/*
 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
 * unrestricted use provided that this legend is included on all tape
 * media and as a part of the software program in whole or part.  Users
 * may copy or modify Sun RPC without charge, but are not authorized
 * to license or distribute it to anyone else except as part of a product or
 * program developed by the user.
 *
 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
 * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
 *
 * Sun RPC is provided with no support and without any obligation on the
 * part of Sun Microsystems, Inc. to assist in its use, correction,
 * modification or enhancement.
 *
 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
 * OR ANY PART THEREOF.
 *
 * In no event will Sun Microsystems, Inc. be liable for any lost revenue
 * or profits or other special, indirect and consequential damages, even if
 * Sun has been advised of the possibility of such damages.
 *
 * Sun Microsystems, Inc.
 * 2550 Garcia Avenue
 * Mountain View, California  94043
 */
#ifndef lint
static char sccsid[] = "@(#)clnt_udp.c 1.5 85/03/17 Copyr 1984 Sun Micro";
#endif

/*
 * clnt_udp.c, Implements a UPD/IP based, client side RPC.
 *
 * Copyright (C) 1984, Sun Microsystems, Inc.
 */

#include <stdio.h>
#include "types.h"
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <netdb.h>
#include <errno.h>
#include "xdr.h"
#include "auth.h"
#include "clnt.h"
#include "rpc_msg.h"
#include "pmap_clnt.h"

char *malloc();
extern int errno;
long random();

/*
 * UDP bases client side rpc operations
 */
static enum clnt_stat   clntudp_call();
static void             clntudp_abort();
static void             clntudp_geterr();
static bool_t           clntudp_freeres();
static void             clntudp_destroy();

static struct clnt_ops udp_ops = {
        clntudp_call,
        clntudp_abort,
        clntudp_geterr,
        clntudp_freeres,
        clntudp_destroy
};

/*
 * Private data kept per client handle
 */
struct cu_data {
        int                cu_sock;
        struct sockaddr_in cu_raddr;
        int                cu_rlen;
        struct timeval     cu_wait;
        struct rpc_err     cu_error;
        XDR                cu_outxdrs;
        u_int              cu_xdrpos;
        char               cu_outbuf[UDPMSGSIZE];
        char               cu_inbuf[UDPMSGSIZE];
};

/*
 * Create a UDP based client handle.
 * If *sockp<0, *sockp is set to a newly created UPD socket.
 * If raddr->sin_port is 0 a binder on the remote machine
 * is consulted for the correct port number.
 * NB: It is the clients responsibility to close *sockp.
 * NB: The rpch->cl_auth is initialized to null authentication.
 *     Caller may wish to set this something more useful.
 *
 * wait is the amount of time used between retransmitting a call if
 * no response has been heard;  retransmition occurs until the actual
 * rpc call times out.
 */
CLIENT *
clntudp_create(raddr, program, version, wait, sockp)
        struct sockaddr_in *raddr;
        u_long program;
        u_long version;
        struct timeval wait;
        register int *sockp;
{
        CLIENT *cl;
        register struct cu_data *cu;
        struct timeval now;
        struct rpc_msg call_msg;

        cl = (CLIENT *)mem_alloc(sizeof(CLIENT));
        if (cl == NULL) {
                fprintf(stderr, "clntudp_create: out of memory\n");
                rpc_createerr.cf_stat = RPC_SYSTEMERROR;
                rpc_createerr.cf_error.re_errno = errno;
                goto fooy;
        }
        cu = (struct cu_data *)mem_alloc(sizeof(*cu));
        if (cu == NULL) {
                fprintf(stderr, "clntudp_create: out of memory\n");
                rpc_createerr.cf_stat = RPC_SYSTEMERROR;
                rpc_createerr.cf_error.re_errno = errno;
                goto fooy;
        }

        (void)gettimeofday(&now, (struct timezone *)0);
        if (raddr->sin_port == 0) {
                u_short port;
                if ((port =
                    pmap_getport(raddr, program, version, IPPROTO_UDP)) == 0) {
                        goto fooy;
                }
                raddr->sin_port = htons(port);
        }
        cl->cl_ops = &udp_ops;
        cl->cl_private = (caddr_t)cu;
        cu->cu_raddr = *raddr;
        cu->cu_rlen = sizeof (cu->cu_raddr);
        cu->cu_wait = wait;
        call_msg.rm_xid = getpid() ^ (int)random() ^ now.tv_sec ^ now.tv_usec;
        call_msg.rm_direction = CALL;
        call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
        call_msg.rm_call.cb_prog = program;
        call_msg.rm_call.cb_vers = version;
        xdrmem_create(&(cu->cu_outxdrs), cu->cu_outbuf,
            UDPMSGSIZE, XDR_ENCODE);
        if (! xdr_callhdr(&(cu->cu_outxdrs), &call_msg)) {
                goto fooy;
        }
        cu->cu_xdrpos = XDR_GETPOS(&(cu->cu_outxdrs));
        cu->cu_sock = (*sockp < 0) ?
            (*sockp = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) :
            *sockp;
        if (cu->cu_sock < 0) {
                rpc_createerr.cf_stat = RPC_SYSTEMERROR;
                rpc_createerr.cf_error.re_errno = errno;
                goto fooy;
        }
        cl->cl_auth = authnone_create();
        return (cl);
fooy:
        mem_free((caddr_t)cu, sizeof(*cu));
        mem_free((caddr_t)cl, sizeof(CLIENT));
        return ((CLIENT *)NULL);
}

static enum clnt_stat
clntudp_call(cl, proc, xargs, argsp, xresults, resultsp, timeout)
        register CLIENT *cl;            /* client handle */
        u_long          proc;           /* procedure number */
        xdrproc_t       xargs;          /* xdr routine for args */
        caddr_t         argsp;          /* pointer to args */
        xdrproc_t       xresults;       /* xdr routine for results */
        caddr_t         resultsp;       /* pointer to results */
        struct timeval  timeout;        /* seconds to wait before giving up */
{
        register struct cu_data *cu = (struct cu_data *)cl->cl_private;
        register XDR *xdrs;
        register int outlen;
        register int inlen;
        int readfds, fromlen;
        register int mask;
        struct sockaddr_in from;
        struct rpc_msg reply_msg;
        XDR reply_xdrs;
        struct timeval time_waited;
        bool_t ok;

call_again:
        time_waited.tv_sec = 0;
        time_waited.tv_usec = 0;
        xdrs = &(cu->cu_outxdrs);
        xdrs->x_op = XDR_ENCODE;
        XDR_SETPOS(xdrs, cu->cu_xdrpos);
        /*
         * the transaction is the first thing in the out buffer
         */
        (*(u_short *)(cu->cu_outbuf))++;
        if ((! XDR_PUTLONG(xdrs, (long *)&proc)) ||
            (! AUTH_MARSHALL(cl->cl_auth, xdrs)) ||
            (! (*xargs)(xdrs, argsp)))
                return (cu->cu_error.re_status = RPC_CANTENCODEARGS);
        outlen = (int)XDR_GETPOS(xdrs);
        while (TRUE) {

                if (sendto(cu->cu_sock, cu->cu_outbuf, outlen, 0,
                    (struct sockaddr *)&(cu->cu_raddr), cu->cu_rlen)
                    != outlen) {
                        cu->cu_error.re_errno = errno;
                        return (cu->cu_error.re_status = RPC_CANTSEND);
                }
                /*
                 * sub-optimal code appears inside the loop because we have
                 * some clock time to spare while the packets are in flight.
                 * (We assume that this is actually only executed once.)
                 */
                reply_msg.acpted_rply.ar_verf = _null_auth;
                reply_msg.acpted_rply.ar_results.where = resultsp;
                reply_msg.acpted_rply.ar_results.proc = xresults;
                mask = 1 << cu->cu_sock;
rcv_again:
                readfds = mask;
                switch (select(32, &readfds, (int *)NULL, (int *)NULL,
                    &(cu->cu_wait))) {

                case 0:
                        time_waited.tv_sec += cu->cu_wait.tv_sec;
                        time_waited.tv_usec += cu->cu_wait.tv_usec;
                        while (time_waited.tv_usec >= 1000000) {
                                time_waited.tv_sec++;
                                time_waited.tv_usec -= 1000000;
                        }
                        if ((time_waited.tv_sec < timeout.tv_sec) ||
                                ((time_waited.tv_sec == timeout.tv_sec) &&
                                (time_waited.tv_usec < timeout.tv_usec)))
                                continue;
                        return (cu->cu_error.re_status = RPC_TIMEDOUT);

                case -1:
                        if (errno == EINTR)
                                goto rcv_again;
                        cu->cu_error.re_errno = errno;
                        return (cu->cu_error.re_status = RPC_CANTRECV);
                }
                if ((readfds & mask) == 0)
                        goto rcv_again;
tryagain:
                fromlen = sizeof(struct sockaddr);
                inlen = recvfrom(cu->cu_sock, cu->cu_inbuf, UDPMSGSIZE, 0,
                    (struct sockaddr *)&from, &fromlen);
                if (inlen < 0) {
                        if (errno == EINTR)
                                goto tryagain;
                        cu->cu_error.re_errno = errno;
                        return (cu->cu_error.re_status = RPC_CANTRECV);
                }
                if (inlen < sizeof(u_long))
                        goto rcv_again;
                /* see if reply transaction id matches sent id */
                if (*((u_long *)(cu->cu_inbuf)) != *((u_long *)(cu->cu_outbuf)))
                        goto rcv_again;
                /* we now assume we have the proper reply */
                break;
        }

        /*
         * now decode and validate the response
         */
        xdrmem_create(&reply_xdrs, cu->cu_inbuf, (u_int)inlen, XDR_DECODE);
        ok = xdr_replymsg(&reply_xdrs, &reply_msg);
        /* XDR_DESTROY(&reply_xdrs);  save a few cycles on noop destroy */
        if (ok) {
                _seterr_reply(&reply_msg, &(cu->cu_error));
                if (cu->cu_error.re_status == RPC_SUCCESS) {
                        if (! AUTH_VALIDATE(cl->cl_auth,
                                &reply_msg.acpted_rply.ar_verf)) {
                                cu->cu_error.re_status = RPC_AUTHERROR;
                                cu->cu_error.re_why = AUTH_INVALIDRESP;
                        }
                        if (reply_msg.acpted_rply.ar_verf.oa_base != NULL) {
                                xdrs->x_op = XDR_FREE;
                                (void)xdr_opaque_auth(xdrs,
                                    &(reply_msg.acpted_rply.ar_verf));
                        }
                }  /* end successful completion */
                else {
                        /* maybe our credentials need to be refreshed ... */
                        if (AUTH_REFRESH(cl->cl_auth))
                                goto call_again;
                }  /* end of unsuccessful completion */
        }  /* end of valid reply message */
        else {
                cu->cu_error.re_status = RPC_CANTDECODERES;
        }
        return (cu->cu_error.re_status);
}

static void
clntudp_geterr(cl, errp)
        CLIENT *cl;
        struct rpc_err *errp;
{
        register struct cu_data *cu = (struct cu_data *)cl->cl_private;

        *errp = cu->cu_error;
}


static bool_t
clntudp_freeres(cl, xdr_res, res_ptr)
        CLIENT *cl;
        xdrproc_t xdr_res;
        caddr_t res_ptr;
{
        register struct cu_data *cu = (struct cu_data *)cl->cl_private;
        register XDR *xdrs = &(cu->cu_outxdrs);

        xdrs->x_op = XDR_FREE;
        return ((*xdr_res)(xdrs, res_ptr));
}

static void
clntudp_abort(/*h*/)
        /*CLIENT *h;*/
{
}

static void
clntudp_destroy(cl)
        CLIENT *cl;
{
        register struct cu_data *cu = (struct cu_data *)cl->cl_private;

        XDR_DESTROY(&(cu->cu_outxdrs));
        mem_free((caddr_t)cu, sizeof(*cu));
        mem_free((caddr_t)cl, sizeof(CLIENT));
}