source: rtems/cpukit/librpc/src/rpc/pmap_rmt.c @ 4202a31

/*
 * 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
 */

#if defined(LIBC_SCCS) && !defined(lint)
/*static char *sccsid = "from: @(#)pmap_rmt.c 1.21 87/08/27 Copyr 1984 Sun Micro";*/
/*static char *sccsid = "from: @(#)pmap_rmt.c   2.2 88/08/01 4.0 RPCSRC";*/
static char *rcsid = "$FreeBSD: src/lib/libc/rpc/pmap_rmt.c,v 1.15 2000/01/27 23:06:40 jasone Exp $";
#endif

/*
 * pmap_rmt.c
 * Client interface to pmap rpc service.
 * remote call and broadcast service
 *
 * Copyright (C) 1984, Sun Microsystems, Inc.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <sys/ioctl.h>
#include <sys/param.h>
#include <sys/socket.h>

#include <net/if.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>

#include <rpc/rpc.h>
#include <rpc/pmap_prot.h>
#include <rpc/pmap_clnt.h>
#include <rpc/pmap_rmt.h>

#include <stdlib.h>
#include <sys/select.h>

#define MAX_BROADCAST_SIZE 1400

static const struct timeval timeout = { 3, 0 };

/*
 * pmapper remote-call-service interface.
 * This routine is used to call the pmapper remote call service
 * which will look up a service program in the port maps, and then
 * remotely call that routine with the given parameters.  This allows
 * programs to do a lookup and call in one step.
*/
enum clnt_stat
pmap_rmtcall(
        struct sockaddr_in *addr,
        u_long prog,
        u_long vers,
        u_long proc,
        xdrproc_t xdrargs,
        caddr_t argsp,
        xdrproc_t xdrres,
        caddr_t resp,
        struct timeval tout,
        u_long *port_ptr)
{
        int sock = -1;
        CLIENT *client;
        struct rmtcallargs a;
        struct rmtcallres r;
        enum clnt_stat stat;

        assert(addr != NULL);
        assert(port_ptr != NULL);

        addr->sin_port = htons(PMAPPORT);
        client = clntudp_create(addr, PMAPPROG, PMAPVERS, timeout, &sock);
        if (client != NULL) {
                a.prog = prog;
                a.vers = vers;
                a.proc = proc;
                a.args_ptr = argsp;
                a.xdr_args = xdrargs;
                r.port_ptr = port_ptr;
                r.results_ptr = resp;
                r.xdr_results = xdrres;
                stat = CLNT_CALL(client, (rpcproc_t)PMAPPROC_CALLIT,
                    (xdrproc_t)xdr_rmtcall_args, &a, (xdrproc_t)xdr_rmtcallres, 
                    &r, tout);
                CLNT_DESTROY(client);
        } else {
                stat = RPC_FAILED;
        }
        if (sock != -1)
                (void)_RPC_close(sock);
        addr->sin_port = 0;
        return (stat);
}


/*
 * XDR remote call arguments
 * written for XDR_ENCODE direction only
 */
bool_t
xdr_rmtcall_args(
        XDR *xdrs,
        struct rmtcallargs *cap)
{
        u_int lenposition, argposition, position;

        assert(xdrs != NULL);
        assert(cap != NULL);

        if (xdr_u_long(xdrs, &(cap->prog)) &&
            xdr_u_long(xdrs, &(cap->vers)) &&
            xdr_u_long(xdrs, &(cap->proc))) {
                lenposition = XDR_GETPOS(xdrs);
                if (! xdr_u_long(xdrs, &(cap->arglen)))
                    return (FALSE);
                argposition = XDR_GETPOS(xdrs);
                if (! (*(cap->xdr_args))(xdrs, cap->args_ptr))
                    return (FALSE);
                position = XDR_GETPOS(xdrs);
                cap->arglen = (u_long)position - (u_long)argposition;
                XDR_SETPOS(xdrs, lenposition);
                if (! xdr_u_long(xdrs, &(cap->arglen)))
                    return (FALSE);
                XDR_SETPOS(xdrs, position);
                return (TRUE);
        }
        return (FALSE);
}

/*
 * XDR remote call results
 * written for XDR_DECODE direction only
 */
bool_t
xdr_rmtcallres(
        XDR *xdrs,
        struct rmtcallres *crp)
{
        caddr_t port_ptr;

        assert(xdrs != NULL);
        assert(crp != NULL);

        port_ptr = (caddr_t)(void *)crp->port_ptr;
        if (xdr_reference(xdrs, &port_ptr, sizeof (u_long),
            (xdrproc_t)xdr_u_long) && xdr_u_long(xdrs, &crp->resultslen)) {
                crp->port_ptr = (u_long *)(void *)port_ptr;
                return ((*(crp->xdr_results))(xdrs, crp->results_ptr));
        }
        return (FALSE);
}


/*
 * The following is kludged-up support for simple rpc broadcasts.
 * Someday a large, complicated system will replace these trivial
 * routines which only support udp/ip .
 */

static int
getbroadcastnets(
        struct in_addr *addrs,
        int sock,  /* any valid socket will do */
        char *buf  /* why allocxate more when we can use existing... */  )
{
        struct ifconf ifc;
        struct ifreq ifreq, *ifr;
        struct sockaddr_in *sin;
        struct  in_addr addr;
        char *cp, *cplim;
        int n, i = 0;

        ifc.ifc_len = UDPMSGSIZE;
        ifc.ifc_buf = buf;
        if (ioctl(sock, SIOCGIFCONF, (char *)&ifc) < 0) {
                perror("broadcast: ioctl (get interface configuration)");
                return (0);
        }
#define max(a, b) (a > b ? a : b)
#define size(p) max((p).sa_len, sizeof(p))
        cplim = buf + ifc.ifc_len; /*skip over if's with big ifr_addr's */
        for (cp = buf; cp < cplim;
                        cp += sizeof (ifr->ifr_name) + size(ifr->ifr_addr)) {
                ifr = (struct ifreq *)cp;
                if (ifr->ifr_addr.sa_family != AF_INET)
                        continue;
                ifreq = *ifr;
                if (ioctl(sock, SIOCGIFFLAGS, (char *)&ifreq) < 0) {
                        perror("broadcast: ioctl (get interface flags)");
                        continue;
                }
                if ((ifreq.ifr_flags & IFF_BROADCAST) &&
                    (ifreq.ifr_flags & IFF_UP)) {
                        sin = (struct sockaddr_in *)&ifr->ifr_addr;
#ifdef SIOCGIFBRDADDR   /* 4.3BSD */
                        if (ioctl(sock, SIOCGIFBRDADDR, (char *)&ifreq) < 0) {
                                addr =
                                    inet_makeaddr(inet_netof(sin->sin_addr),
                                    INADDR_ANY);
                        } else {
                                addr = ((struct sockaddr_in*)
                                  &ifreq.ifr_addr)->sin_addr;
                        }
#else /* 4.2 BSD */
                        addr = inet_makeaddr(inet_netof(sin->sin_addr),
                            INADDR_ANY);
#endif
                        for (n=i-1; n>=0; n--) {
                                if (addr.s_addr == addrs[n].s_addr)
                                        break;
                        }
                        if (n<0) {
                                addrs[i++] = addr;
                        }
                }
        }
        return (i);
}

typedef bool_t (*resultproc_t)(caddr_t, struct sockaddr_in *);

enum clnt_stat
clnt_broadcast(
        u_long          prog,           /* program number */
        u_long          vers,           /* version number */
        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 */
        resultproc_t    eachresult      /* call with each result obtained */ )
{
        enum clnt_stat stat = RPC_SUCCESS; /* to avoid warning */
        AUTH *unix_auth = authunix_create_default();
        XDR xdr_stream;
        register XDR *xdrs = &xdr_stream;
        int outlen, inlen, nets;
        socklen_t fromlen;
        register int sock;
        int on = 1;
        fd_set *fds = 0, readfds; /* initialized to avoid warning */
        register int i;
        bool_t done = FALSE;
        register u_long xid;
        u_long port;
        struct in_addr addrs[20];
        struct sockaddr_in baddr, raddr; /* broadcast and response addresses */
        struct rmtcallargs a;
        struct rmtcallres r;
        struct rpc_msg msg;
        struct timeval t, tv;
        char outbuf[MAX_BROADCAST_SIZE], inbuf[UDPMSGSIZE];
        static uintptr_t disrupt;

        if (disrupt == 0)
                disrupt = (uintptr_t) resultsp;

        /*
         * initialization: create a socket, a broadcast address, and
         * preserialize the arguments into a send buffer.
         */
        if ((sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
                perror("Cannot create socket for broadcast rpc");
                stat = RPC_CANTSEND;
                goto done_broad;
        }
#ifdef SO_BROADCAST
        if (setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &on, sizeof (on)) < 0) {
                perror("Cannot set socket option SO_BROADCAST");
                stat = RPC_CANTSEND;
                goto done_broad;
        }
#endif /* def SO_BROADCAST */
        if (sock + 1 > FD_SETSIZE) {
                int bytes = howmany(sock + 1, NFDBITS) * sizeof(fd_mask);
                fds = (fd_set *)malloc(bytes);
                if (fds == NULL) {
                        stat = RPC_CANTSEND;
                        goto done_broad;
                }
                memset(fds, 0, bytes);
        } else {
                fds = &readfds;
                FD_ZERO(fds);
        }

        nets = getbroadcastnets(addrs, sock, inbuf);
        memset(&baddr, 0, sizeof (baddr));
        baddr.sin_len = sizeof(struct sockaddr_in);
        baddr.sin_family = AF_INET;
        baddr.sin_port = htons(PMAPPORT);
        baddr.sin_addr.s_addr = htonl(INADDR_ANY);
        (void)gettimeofday(&t, (struct timezone *)0);
        msg.rm_xid = xid = (++disrupt) ^ getpid() ^ t.tv_sec ^ t.tv_usec;
        t.tv_usec = 0;
        msg.rm_direction = CALL;
        msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
        msg.rm_call.cb_prog = PMAPPROG;
        msg.rm_call.cb_vers = PMAPVERS;
        msg.rm_call.cb_proc = PMAPPROC_CALLIT;
        msg.rm_call.cb_cred = unix_auth->ah_cred;
        msg.rm_call.cb_verf = unix_auth->ah_verf;
        a.prog = prog;
        a.vers = vers;
        a.proc = proc;
        a.xdr_args = xargs;
        a.args_ptr = argsp;
        r.port_ptr = &port;
        r.xdr_results = xresults;
        r.results_ptr = resultsp;
        xdrmem_create(xdrs, outbuf, MAX_BROADCAST_SIZE, XDR_ENCODE);
        if ((! xdr_callmsg(xdrs, &msg)) || (! xdr_rmtcall_args(xdrs, &a))) {
                stat = RPC_CANTENCODEARGS;
                goto done_broad;
        }
        outlen = (int)xdr_getpos(xdrs);
        xdr_destroy(xdrs);
        /*
         * Basic loop: broadcast a packet and wait a while for response(s).
         * The response timeout grows larger per iteration.
         *
         * XXX This will loop about 5 times the stop. If there are
         * lots of signals being received by the process it will quit
         * send them all in one quick burst, not paying attention to
         * the intended function of sending them slowly over half a
         * minute or so
         */
        for (t.tv_sec = 4; t.tv_sec <= 14; t.tv_sec += 2) {
                for (i = 0; i < nets; i++) {
                        baddr.sin_addr = addrs[i];
                        if (sendto(sock, outbuf, outlen, 0,
                                (struct sockaddr *)&baddr,
                                sizeof (struct sockaddr)) != outlen) {
                                perror("Cannot send broadcast packet");
                                stat = RPC_CANTSEND;
                                goto done_broad;
                        }
                }
                if (eachresult == NULL) {
                        stat = RPC_SUCCESS;
                        goto done_broad;
                }
        recv_again:
                msg.acpted_rply.ar_verf = _null_auth;
                msg.acpted_rply.ar_results.where = (caddr_t)&r;
                msg.acpted_rply.ar_results.proc = (xdrproc_t) xdr_rmtcallres;
                /* XXX we know the other bits are still clear */
                FD_SET(sock, fds);
                tv = t;         /* for select() that copies back */
                switch (select(sock + 1, fds, NULL, NULL, &tv)) {

                case 0:  /* timed out */
                        stat = RPC_TIMEDOUT;
                        continue;

                case -1:  /* some kind of error */
                        if (errno == EINTR)
                                goto recv_again;
                        perror("Broadcast select problem");
                        stat = RPC_CANTRECV;
                        goto done_broad;

                }  /* end of select results switch */
        try_again:
                fromlen = sizeof(struct sockaddr);
                inlen = recvfrom(sock, inbuf, UDPMSGSIZE, 0,
                        (struct sockaddr *)&raddr, &fromlen);
                if (inlen < 0) {
                        if (errno == EINTR)
                                goto try_again;
                        perror("Cannot receive reply to broadcast");
                        stat = RPC_CANTRECV;
                        goto done_broad;
                }
                if (inlen < sizeof(u_int32_t))
                        goto recv_again;
                /*
                 * see if reply transaction id matches sent id.
                 * If so, decode the results.
                 */
                xdrmem_create(xdrs, inbuf, (u_int)inlen, XDR_DECODE);
                if (xdr_replymsg(xdrs, &msg)) {
                        if ((msg.rm_xid == xid) &&
                                (msg.rm_reply.rp_stat == MSG_ACCEPTED) &&
                                (msg.acpted_rply.ar_stat == SUCCESS)) {
                                raddr.sin_port = htons((u_short)port);
                                done = (*eachresult)(resultsp, &raddr);
                        }
                        /* otherwise, we just ignore the errors ... */
                }
                xdrs->x_op = XDR_FREE;
                msg.acpted_rply.ar_results.proc = (xdrproc_t) xdr_void;
                (void)xdr_replymsg(xdrs, &msg);
                (void)(*xresults)(xdrs, resultsp);
                xdr_destroy(xdrs);
                if (done) {
                        stat = RPC_SUCCESS;
                        goto done_broad;
                } else {
                        goto recv_again;
                }
        }
done_broad:
        if (fds != &readfds)
                free(fds);
        if (sock >= 0)
                (void)_RPC_close(sock);
        AUTH_DESTROY(unix_auth);
        return (stat);
}