/* @(#)clnt_udp.c       2.2 88/08/01 4.0 RPCSRC */
/*
 * Copyright (c) 2010, Oracle America, 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 the "Oracle America, 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(lint) && defined(SCCSIDS)
static char sccsid[] = "@(#)clnt_udp.c 1.39 87/08/11 Copyr 1984 Sun Micro";
#endif

/*
 * clnt_udp.c, Implements a UDP/IP based, client side RPC.
 */

#include <stdio.h>
#include <unistd.h>
#include <gssrpc/rpc.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#if defined(sun)
#include <sys/filio.h>
#endif
#include <netdb.h>
#include <errno.h>
#include <string.h>
#include <gssrpc/pmap_clnt.h>
#include <port-sockets.h>
#include <errno.h>

#ifndef GETSOCKNAME_ARG3_TYPE
#define GETSOCKNAME_ARG3_TYPE int
#endif

/*
 * UDP bases client side rpc operations
 */
static enum clnt_stat   clntudp_call(CLIENT *, rpcproc_t, xdrproc_t, void *,
                                     xdrproc_t, void *, struct timeval);
static void             clntudp_abort(CLIENT *);
static void             clntudp_geterr(CLIENT *, struct rpc_err *);
static bool_t           clntudp_freeres(CLIENT *, xdrproc_t, void *);
static bool_t           clntudp_control(CLIENT *, int, void *);
static void             clntudp_destroy(CLIENT *);

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

/*
 * Private data kept per client handle
 */
struct cu_data {
        SOCKET             cu_sock;
        bool_t             cu_closeit;
        struct sockaddr_in cu_raddr;
        int                cu_rlen;
        struct sockaddr_in cu_laddr;
        GETSOCKNAME_ARG3_TYPE  cu_llen;
        struct timeval     cu_wait;
        struct timeval     cu_total;
        struct rpc_err     cu_error;
        XDR                cu_outxdrs;
        u_int              cu_xdrpos;
        u_int              cu_sendsz;
        char               *cu_outbuf;
        u_int              cu_recvsz;
        char               cu_inbuf[1];
};

/*
 * 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;  retransmission occurs until the actual
 * rpc call times out.
 *
 * sendsz and recvsz are the maximum allowable packet sizes that can be
 * sent and received.
 */
CLIENT *
clntudp_bufcreate(
        struct sockaddr_in *raddr,
        rpcprog_t program,
        rpcvers_t version,
        struct timeval wait,
        int *sockp,
        u_int sendsz,
        u_int recvsz)
{
        CLIENT *cl;
        struct cu_data *cu = 0;
        struct timeval now;
        struct rpc_msg call_msg;

        cl = (CLIENT *)mem_alloc(sizeof(CLIENT));
        if (cl == NULL) {
                (void) fprintf(stderr, "clntudp_create: out of memory\n");
                rpc_createerr.cf_stat = RPC_SYSTEMERROR;
                rpc_createerr.cf_error.re_errno = errno;
                goto fooy;
        }
        sendsz = ((sendsz + 3) / 4) * 4;
        recvsz = ((recvsz + 3) / 4) * 4;
        cu = (struct cu_data *)mem_alloc(sizeof(*cu) + sendsz + recvsz);
        if (cu == NULL) {
                (void) fprintf(stderr, "clntudp_create: out of memory\n");
                rpc_createerr.cf_stat = RPC_SYSTEMERROR;
                rpc_createerr.cf_error.re_errno = errno;
                goto fooy;
        }
        cu->cu_outbuf = &cu->cu_inbuf[recvsz];

        (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;
        cu->cu_total.tv_sec = -1;
        cu->cu_total.tv_usec = -1;
        cu->cu_sendsz = sendsz;
        cu->cu_recvsz = recvsz;
        call_msg.rm_xid = getpid() ^ 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,
            sendsz, XDR_ENCODE);
        if (! xdr_callhdr(&(cu->cu_outxdrs), &call_msg)) {
                goto fooy;
        }
        cu->cu_xdrpos = XDR_GETPOS(&(cu->cu_outxdrs));
        if (*sockp < 0) {
                int dontblock = 1;

                *sockp = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
                if (*sockp < 0) {
                        rpc_createerr.cf_stat = RPC_SYSTEMERROR;
                        rpc_createerr.cf_error.re_errno = errno;
                        goto fooy;
                }
                /* attempt to bind to prov port */
                (void)bindresvport_sa(*sockp, NULL);
                /* the sockets rpc controls are non-blocking */
                (void)ioctl(*sockp, FIONBIO, (char *) &dontblock);
                cu->cu_closeit = TRUE;
        } else {
                cu->cu_closeit = FALSE;
        }
        if (connect(*sockp, (struct sockaddr *)raddr, sizeof(*raddr)) < 0)
             goto fooy;
        cu->cu_llen = sizeof(cu->cu_laddr);
        if (getsockname(*sockp, (struct sockaddr *)&cu->cu_laddr, &cu->cu_llen) < 0)
             goto fooy;

        cu->cu_sock = *sockp;
        cl->cl_auth = authnone_create();
        return (cl);
fooy:
        if (cu)
                mem_free((caddr_t)cu, sizeof(*cu) + sendsz + recvsz);
        if (cl)
                mem_free((caddr_t)cl, sizeof(CLIENT));
        return ((CLIENT *)NULL);
}

CLIENT *
clntudp_create(
        struct sockaddr_in *raddr,
        rpcprog_t program,
        rpcvers_t version,
        struct timeval wait,
        int *sockp)
{

        return(clntudp_bufcreate(raddr, program, version, wait, sockp,
            UDPMSGSIZE, UDPMSGSIZE));
}

static enum clnt_stat
clntudp_call(
        CLIENT  *cl,                    /* client handle */
        rpcproc_t       proc,           /* procedure number */
        xdrproc_t       xargs,          /* xdr routine for args */
        void *          argsp,          /* pointer to args */
        xdrproc_t       xresults,       /* xdr routine for results */
        void *          resultsp,       /* pointer to results */
        struct timeval  utimeout        /* seconds to wait before
                                         * giving up */
        )
{
        struct cu_data *cu = (struct cu_data *)cl->cl_private;
        XDR *xdrs;
        int outlen;
        ssize_t inlen;
        GETSOCKNAME_ARG3_TYPE fromlen; /* Assumes recvfrom uses same type */
#ifdef FD_SETSIZE
        fd_set readfds;
        fd_set mask;
#else
        int readfds;
        int mask;
#endif /* def FD_SETSIZE */
        struct sockaddr_in from;
        struct rpc_msg reply_msg;
        XDR reply_xdrs;
        struct timeval time_waited, seltimeout;
        bool_t ok;
        int nrefreshes = 2;     /* number of times to refresh cred */
        struct timeval timeout;
        long procl = proc;

        if (cu->cu_total.tv_usec == -1) {
                timeout = utimeout;     /* use supplied timeout */
        } else {
                timeout = cu->cu_total; /* use default timeout */
        }

        time_waited.tv_sec = 0;
        time_waited.tv_usec = 0;
call_again:
        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
         */
        (*(uint32_t *)(void *)(cu->cu_outbuf))++;
        if ((! XDR_PUTLONG(xdrs, &procl)) ||
            (! AUTH_MARSHALL(cl->cl_auth, xdrs)) ||
            (! AUTH_WRAP(cl->cl_auth, xdrs, xargs, argsp)))
                return (cu->cu_error.re_status = RPC_CANTENCODEARGS);
        outlen = (int)XDR_GETPOS(xdrs);

send_again:
        if (send(cu->cu_sock, cu->cu_outbuf, (u_int)outlen, 0) != outlen) {
                cu->cu_error.re_errno = errno;
                return (cu->cu_error.re_status = RPC_CANTSEND);
        }

        /*
         * Hack to provide rpc-based message passing
         */
        if (timeout.tv_sec == 0 && timeout.tv_usec == 0) {
                return (cu->cu_error.re_status = RPC_TIMEDOUT);
        }
        /*
         * sub-optimal code appears here 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 = gssrpc__null_auth;
        reply_msg.acpted_rply.ar_results.where = NULL;
        reply_msg.acpted_rply.ar_results.proc = xdr_void;
#ifdef FD_SETSIZE
        FD_ZERO(&mask);
        FD_SET(cu->cu_sock, &mask);
#else
        mask = 1 << cu->cu_sock;
#endif /* def FD_SETSIZE */
        for (;;) {
                readfds = mask;
                seltimeout = cu->cu_wait;
                switch (select(gssrpc__rpc_dtablesize(), &readfds, (fd_set *)NULL,
                               (fd_set *)NULL, &seltimeout)) {

                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)))
                                goto send_again;
                        return (cu->cu_error.re_status = RPC_TIMEDOUT);

                /*
                 * buggy in other cases because time_waited is not being
                 * updated.
                 */
                case -1:
                        if (errno == EINTR)
                                continue;
                        cu->cu_error.re_errno = errno;
                        return (cu->cu_error.re_status = RPC_CANTRECV);
                }
                do {
                        fromlen = sizeof(struct sockaddr);
                        inlen = recvfrom(cu->cu_sock, cu->cu_inbuf,
                                cu->cu_recvsz, 0,
                                (struct sockaddr *)&from, &fromlen);
                } while (inlen < 0 && errno == EINTR);
                if (inlen < 0) {
                        if (errno == EWOULDBLOCK)
                                continue;
                        cu->cu_error.re_errno = errno;
                        return (cu->cu_error.re_status = RPC_CANTRECV);
                }
                if ((size_t)inlen < sizeof(uint32_t))
                        continue;
                /* see if reply transaction id matches sent id */
                if (*((uint32_t *)(void *)(cu->cu_inbuf)) !=
                    *((uint32_t *)(void *)(cu->cu_outbuf)))
                        continue;
                /* 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) {
                gssrpc__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;
                        } else if (! AUTH_UNWRAP(cl->cl_auth, &reply_xdrs,
                                                 xresults, resultsp)) {
                             if (cu->cu_error.re_status == RPC_SUCCESS)
                                  cu->cu_error.re_status = RPC_CANTDECODERES;
                        }
                }  /* end successful completion */
                else {
                        /* maybe our credentials need to be refreshed ... */
                        if (nrefreshes > 0 &&
                            AUTH_REFRESH(cl->cl_auth, &reply_msg)) {
                                nrefreshes--;
                                goto call_again;
                        }
                }  /* end of unsuccessful completion */
                /* free verifier */
                if ((reply_msg.rm_reply.rp_stat == MSG_ACCEPTED) &&
                    (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 of valid reply message */
        else {
                /*
                 * It's possible for xdr_replymsg() to fail partway
                 * through its attempt to decode the result from the
                 * server. If this happens, it will leave the reply
                 * structure partially populated with dynamically
                 * allocated memory. (This can happen if someone uses
                 * clntudp_bufcreate() to create a CLIENT handle and
                 * specifies a receive buffer size that is too small.)
                 * This memory must be free()ed to avoid a leak.
                 */
                enum xdr_op op = reply_xdrs.x_op;
                reply_xdrs.x_op = XDR_FREE;
                xdr_replymsg(&reply_xdrs, &reply_msg);
                reply_xdrs.x_op = op;
                cu->cu_error.re_status = RPC_CANTDECODERES;
        }
        return (cu->cu_error.re_status);
}

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

        *errp = cu->cu_error;
}


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

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


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

static bool_t
clntudp_control(
        CLIENT *cl,
        int request,
        void *info)
{
        struct cu_data *cu = cl->cl_private;

        switch (request) {
        case CLSET_TIMEOUT:
                cu->cu_total = *(struct timeval *)info;
                break;
        case CLGET_TIMEOUT:
                *(struct timeval *)info = cu->cu_total;
                break;
        case CLSET_RETRY_TIMEOUT:
                cu->cu_wait = *(struct timeval *)info;
                break;
        case CLGET_RETRY_TIMEOUT:
                *(struct timeval *)info = cu->cu_wait;
                break;
        case CLGET_SERVER_ADDR:
                *(struct sockaddr_in *)info = cu->cu_raddr;
                break;
        case CLGET_LOCAL_ADDR:
                *(struct sockaddr_in *)info = cu->cu_laddr;
                break;
        default:
                return (FALSE);
        }
        return (TRUE);
}

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

        if (cu->cu_closeit)
                (void)closesocket(cu->cu_sock);
        XDR_DESTROY(&(cu->cu_outxdrs));
        mem_free((caddr_t)cu, (sizeof(*cu) + cu->cu_sendsz + cu->cu_recvsz));
        mem_free((caddr_t)cl, sizeof(CLIENT));
}