usr/src/new/sunrpc/clnt_tcp.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_tcp.c 1.5 85/03/17 Copyr 1984 Sun Micro";
#endif

/*
 * clnt_tcp.c, Implements a TCP/IP based, client side RPC.
 *
 * Copyright (C) 1984, Sun Microsystems, Inc.
 *
 * TCP based RPC supports 'batched calls'.
 * A sequence of calls may be batched-up in a send buffer.  The rpc call
 * return immediately to the client even though the call was not necessarily
 * sent.  The batching occurs iff the results' xdr routine is NULL (0) AND
 * the rpc timeout value is zero (see clnt.h, rpc).
 *
 * Clients should NOT casually batch calls that in fact return results; that is,
 * the server side should be aware that a call is batched and not produce any
 * return message.  Batched calls that produce many result messages can
 * deadlock (netlock) the client and the server....
 *
 * Now go hang yourself.
 */

#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"

#define MCALL_MSG_SIZE 24

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

static int      readtcp();
static int      writetcp();

static enum clnt_stat   clnttcp_call();
static void             clnttcp_abort();
static void             clnttcp_geterr();
static bool_t           clnttcp_freeres();
static void             clnttcp_destroy();

static struct clnt_ops tcp_ops = {
        clnttcp_call,
        clnttcp_abort,
        clnttcp_geterr,
        clnttcp_freeres,
        clnttcp_destroy
};

struct ct_data {
        int             ct_sock;
        struct timeval  ct_wait;
        struct rpc_err  ct_error;
        char            ct_mcall[MCALL_MSG_SIZE];       /* marshalled callmsg */
        u_int           ct_mpos;                        /* pos after marshal */
        XDR             ct_xdrs;
};

/*
 * Create a client handle for a tcp/ip connection.
 * If *sockp<0, *sockp is set to a newly created TCP socket and it is
 * connected to raddr.  If *sockp non-negative then
 * raddr is ignored.  The rpc/tcp package does buffering
 * similar to stdio, so the client must pick send and receive buffer sizes,];
 * 0 => use the default.
 * If raddr->sin_port is 0, then a binder on the remote machine is
 * consulted for the right port number.
 * NB: *sockp is copied into a private area.
 * NB: It is the clients responsibility to close *sockp.
 * NB: The rpch->cl_auth is set null authentication.  Caller may wish to set this
 * something more useful.
 */
CLIENT *
clnttcp_create(raddr, prog, vers, sockp, sendsz, recvsz)
        struct sockaddr_in *raddr;
        u_long prog;
        u_long vers;
        register int *sockp;
        u_int sendsz;
        u_int recvsz;
{
        CLIENT *h;
        register struct ct_data *ct;
        struct timeval now;
        struct rpc_msg call_msg;

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

        /*
         * If no port number given ask the pmap for one
         */
        if (raddr->sin_port == 0) {
                u_short port;
                if ((port = pmap_getport(raddr, prog, vers, IPPROTO_TCP)) == 0) {
                        mem_free((caddr_t)ct, sizeof(struct ct_data));
                        mem_free((caddr_t)h, sizeof(CLIENT));
                        return ((CLIENT *)NULL);
                }
                raddr->sin_port = htons(port);
        }

        /*
         * If no socket given, open one
         */
        if (*sockp < 0) {
                if (((*sockp = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0)
                    || (connect(*sockp, (struct sockaddr *)raddr,
                    sizeof(*raddr)) < 0)) {
                        rpc_createerr.cf_stat = RPC_SYSTEMERROR;
                        rpc_createerr.cf_error.re_errno = errno;
                        goto fooy;
                }
        }

        /*
         * Set up private data struct
         */
        ct->ct_sock = *sockp;
        ct->ct_wait.tv_usec = 0;

        /*
         * Initialize call message
         */
        (void)gettimeofday(&now, (struct timezone *)0);
        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 = prog;
        call_msg.rm_call.cb_vers = vers;

        /*
         * pre-serialize the staic part of the call msg and stash it away
         */
        xdrmem_create(&(ct->ct_xdrs), ct->ct_mcall, MCALL_MSG_SIZE,
            XDR_ENCODE);
        if (! xdr_callhdr(&(ct->ct_xdrs), &call_msg)) {
                goto fooy;
        }
        ct->ct_mpos = XDR_GETPOS(&(ct->ct_xdrs));
        XDR_DESTROY(&(ct->ct_xdrs));

        /*
         * Create a client handle which uses xdrrec for serialization
         * and authnone for authentication.
         */
        xdrrec_create(&(ct->ct_xdrs), sendsz, recvsz,
            (caddr_t)ct, readtcp, writetcp);
        h->cl_ops = &tcp_ops;
        h->cl_private = (caddr_t) ct;
        h->cl_auth = authnone_create();
        return (h);

fooy:
        /*
         * Something goofed, free stuff and barf
         */
        mem_free((caddr_t)ct, sizeof(struct ct_data));
        mem_free((caddr_t)h, sizeof(CLIENT));
        (void)close(*sockp);
        return ((CLIENT *)NULL);
}

static enum clnt_stat
clnttcp_call(h, proc, xdr_args, args_ptr, xdr_results, results_ptr, timeout)
        register CLIENT *h;
        u_long proc;
        xdrproc_t xdr_args;
        caddr_t args_ptr;
        xdrproc_t xdr_results;
        caddr_t results_ptr;
        struct timeval timeout;
{
        register struct ct_data *ct = (struct ct_data *) h->cl_private;
        register XDR *xdrs = &(ct->ct_xdrs);
        struct rpc_msg reply_msg;
        u_long x_id;
        u_long *msg_x_id = (u_long *)(ct->ct_mcall);    /* yuk */
        register bool_t shipnow;

        ct->ct_wait = timeout;
        shipnow =
            (xdr_results == (xdrproc_t)0 && timeout.tv_sec == 0
            && timeout.tv_usec == 0) ? FALSE : TRUE;

call_again:
        xdrs->x_op = XDR_ENCODE;
        ct->ct_error.re_status = RPC_SUCCESS;
        x_id = ntohl(--(*msg_x_id));
        if ((! XDR_PUTBYTES(xdrs, ct->ct_mcall, ct->ct_mpos)) ||
            (! XDR_PUTLONG(xdrs, (long *)&proc)) ||
            (! AUTH_MARSHALL(h->cl_auth, xdrs)) ||
            (! (*xdr_args)(xdrs, args_ptr))) {
                if (ct->ct_error.re_status == RPC_SUCCESS)
                        ct->ct_error.re_status = RPC_CANTENCODEARGS;
                (void)xdrrec_endofrecord(xdrs, TRUE);
                return (ct->ct_error.re_status);
        }
        if (! xdrrec_endofrecord(xdrs, shipnow))
                return (ct->ct_error.re_status = RPC_CANTSEND);
        if (! shipnow)
                return (RPC_SUCCESS);
        xdrs->x_op = XDR_DECODE;

        /*
         * Keep receiving until we get a valid transaction id
         */
        while (TRUE) {
                reply_msg.acpted_rply.ar_verf = _null_auth;
                reply_msg.acpted_rply.ar_results.where = NULL;
                reply_msg.acpted_rply.ar_results.proc = xdr_void;
                if (! xdrrec_skiprecord(xdrs))
                        return (ct->ct_error.re_status);
                /* now decode and validate the response header */
                if (! xdr_replymsg(xdrs, &reply_msg)) {
                        if (ct->ct_error.re_status == RPC_SUCCESS)
                                continue;
                        return (ct->ct_error.re_status);
                }
                if (reply_msg.rm_xid == x_id)
                        break;
        }

        /*
         * process header
         */
        _seterr_reply(&reply_msg, &(ct->ct_error));
        if (ct->ct_error.re_status == RPC_SUCCESS) {
                if (! AUTH_VALIDATE(h->cl_auth, &reply_msg.acpted_rply.ar_verf)) {
                        ct->ct_error.re_status = RPC_AUTHERROR;
                        ct->ct_error.re_why = AUTH_INVALIDRESP;
                } else if (! (*xdr_results)(xdrs, results_ptr)) {
                        if (ct->ct_error.re_status == RPC_SUCCESS)
                                ct->ct_error.re_status = RPC_CANTDECODERES;
                }
                /* free verifier ... */
                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(h->cl_auth))
                        goto call_again;
        }  /* end of unsuccessful completion */
        return (ct->ct_error.re_status);
}

static void
clnttcp_geterr(h, errp)
        CLIENT *h;
        struct rpc_err *errp;
{
        register struct ct_data *ct =
            (struct ct_data *) h->cl_private;

        *errp = ct->ct_error;
}

static bool_t
clnttcp_freeres(cl, xdr_res, res_ptr)
        CLIENT *cl;
        xdrproc_t xdr_res;
        caddr_t res_ptr;
{
        register struct ct_data *ct = (struct ct_data *)cl->cl_private;
        register XDR *xdrs = &(ct->ct_xdrs);

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

static void
clnttcp_abort()
{
}

static void
clnttcp_destroy(h)
        CLIENT *h;
{
        register struct ct_data *ct =
            (struct ct_data *) h->cl_private;

        XDR_DESTROY(&(ct->ct_xdrs));
        mem_free((caddr_t)ct, sizeof(struct ct_data));
        mem_free((caddr_t)h, sizeof(CLIENT));
}

/*
 * Interface between xdr serializer and tcp connection.
 * Behaves like the system calls, read & write, but keeps some error state
 * around for the rpc level.
 */
static int
readtcp(ct, buf, len)
        register struct ct_data *ct;
        caddr_t buf;
        register int len;
{
        register int mask = 1 << (ct->ct_sock);
        int readfds;

        while (TRUE) {
                readfds = mask;
                switch (select(32, &readfds, (int*)NULL, (int*)NULL,
                    &(ct->ct_wait))) {

                case 0:
                        ct->ct_error.re_status = RPC_TIMEDOUT;
                        return (-1);

                case -1:
                        if (errno == EINTR)
                                continue;
                        ct->ct_error.re_status = RPC_CANTRECV;
                        ct->ct_error.re_errno = errno;
                        return (-1);
                }
                if (readfds == mask)
                        break;
        }
        if ((len = read(ct->ct_sock, buf, len)) == -1) {
                ct->ct_error.re_errno = errno;
                ct->ct_error.re_status = RPC_CANTRECV;
        }
        return (len);
}

static int
writetcp(ct, buf, len)
        struct ct_data *ct;
        caddr_t buf;
        int len;
{
        register int i, cnt;

        for (cnt = len; cnt > 0; cnt -= i, buf += i) {
                if ((i = write(ct->ct_sock, buf, cnt)) == -1) {
                        ct->ct_error.re_errno = errno;
                        ct->ct_error.re_status = RPC_CANTSEND;
                        return (-1);
                }
        }
        return (len);
}