/*      $NetBSD: clnt_bcast.c,v 1.3 2000/07/06 03:05:20 christos Exp $  */

/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * 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.
 */
/*
 * Copyright (c) 1986-1991 by Sun Microsystems Inc. 
 */

/*
 * clnt_bcast.c
 * Client interface to broadcast service.
 *
 * Copyright (C) 1988, Sun Microsystems, Inc.
 *
 * The following is kludged-up support for simple rpc broadcasts.
 * Someday a large, complicated system will replace these routines.
 */

#include "namespace.h"
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/queue.h>
#include <net/if.h>
#include <netinet/in.h>
#include <ifaddrs.h>
#include <sys/poll.h>
#include <rpc/rpc.h>
#ifdef PORTMAP
#include <rpc/pmap_prot.h>
#include <rpc/pmap_clnt.h>
#include <rpc/pmap_rmt.h>
#endif                          /* PORTMAP */
#include <rpc/nettype.h>
#include <arpa/inet.h>
#ifdef RPC_DEBUG
#include <stdio.h>
#endif
#include <errno.h>
#include <stdlib.h>
#include <unistd.h>
#include <netdb.h>
#include <err.h>
#include <string.h>
#include "un-namespace.h"

#include "rpc_com.h"

#define MAXBCAST 20     /* Max no of broadcasting transports */
#define INITTIME 4000   /* Time to wait initially */
#define WAITTIME 8000   /* Maximum time to wait */

/*
 * If nettype is NULL, it broadcasts on all the available
 * datagram_n transports. May potentially lead to broadacst storms
 * and hence should be used with caution, care and courage.
 *
 * The current parameter xdr packet size is limited by the max tsdu
 * size of the transport. If the max tsdu size of any transport is
 * smaller than the parameter xdr packet, then broadcast is not
 * sent on that transport.
 *
 * Also, the packet size should be less the packet size of
 * the data link layer (for ethernet it is 1400 bytes).  There is
 * no easy way to find out the max size of the data link layer and
 * we are assuming that the args would be smaller than that.
 *
 * The result size has to be smaller than the transport tsdu size.
 *
 * If PORTMAP has been defined, we send two packets for UDP, one for
 * rpcbind and one for portmap. For those machines which support
 * both rpcbind and portmap, it will cause them to reply twice, and
 * also here it will get two responses ... inefficient and clumsy.
 */

struct broadif {
        int index;
        struct sockaddr_storage broadaddr;
        TAILQ_ENTRY(broadif) link;
};

typedef TAILQ_HEAD(, broadif) broadlist_t;

int __rpc_getbroadifs(int, int, int, broadlist_t *);
void __rpc_freebroadifs(broadlist_t *);
int __rpc_broadenable(int, int, struct broadif *);

int __rpc_lowvers = 0;

int
__rpc_getbroadifs(int af, int proto, int socktype, broadlist_t *list)
{
        int count = 0;
        struct broadif *bip;
        struct ifaddrs *ifap, *ifp;
#ifdef INET6
        struct sockaddr_in6 *sin6;
#endif
        struct sockaddr_in *sin;
        struct addrinfo hints, *res;

        if (getifaddrs(&ifp) < 0)
                return 0;

        memset(&hints, 0, sizeof hints);

        hints.ai_family = af;
        hints.ai_protocol = proto;
        hints.ai_socktype = socktype;

        if (getaddrinfo(NULL, "sunrpc", &hints, &res) != 0) {
                freeifaddrs(ifp);
                return 0;
        }

        for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) {
                if (ifap->ifa_addr->sa_family != af ||
                    !(ifap->ifa_flags & IFF_UP))
                        continue;
                bip = (struct broadif *)malloc(sizeof *bip);
                if (bip == NULL)
                        break;
                bip->index = if_nametoindex(ifap->ifa_name);
                if (
#ifdef INET6
                af != AF_INET6 &&
#endif
                (ifap->ifa_flags & IFF_BROADCAST) &&
                 ifap->ifa_broadaddr) {
                        memcpy(&bip->broadaddr, ifap->ifa_broadaddr,
                            (size_t)ifap->ifa_broadaddr->sa_len);
                        sin = (struct sockaddr_in *)(void *)&bip->broadaddr;
                        sin->sin_port =
                            ((struct sockaddr_in *)
                            (void *)res->ai_addr)->sin_port;
                } else
#ifdef INET6
                if (af == AF_INET6 && (ifap->ifa_flags & IFF_MULTICAST)) {
                        sin6 = (struct sockaddr_in6 *)(void *)&bip->broadaddr;
                        inet_pton(af, RPCB_MULTICAST_ADDR, &sin6->sin6_addr);
                        sin6->sin6_family = af;
                        sin6->sin6_len = sizeof *sin6;
                        sin6->sin6_port =
                            ((struct sockaddr_in6 *)
                            (void *)res->ai_addr)->sin6_port;
                        sin6->sin6_scope_id = bip->index;
                } else
#endif
                {
                        free(bip);
                        continue;
                }
                TAILQ_INSERT_TAIL(list, bip, link);
                count++;
        }
        freeifaddrs(ifp);
        freeaddrinfo(res);

        return count;
}

void
__rpc_freebroadifs(broadlist_t *list)
{
        struct broadif *bip, *next;

        bip = TAILQ_FIRST(list);

        while (bip != NULL) {
                next = TAILQ_NEXT(bip, link);
                free(bip);
                bip = next;
        }
}

int
/*ARGSUSED*/
__rpc_broadenable(int af, int s, struct broadif *bip)
{
        int o = 1;

#if 0
        if (af == AF_INET6) {
                fprintf(stderr, "set v6 multicast if to %d\n", bip->index);
                if (_setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_IF, &bip->index,
                    sizeof bip->index) < 0)
                        return -1;
        } else
#endif
                if (_setsockopt(s, SOL_SOCKET, SO_BROADCAST, &o, sizeof o) < 0)
                        return -1;

        return 0;
}

/*
 * rpc_broadcast_exp()
 *
 * prog      - program number
 * vers      - version number
 * proc      - procedure number
 * xargs     - xdr routine for args
 * argsp     - pointer to args
 * xresults  - xdr routine for results
 * resultsp  - pointer to results
 * eachresult - call with each result obtained
 * inittime  - how long to wait initially
 * waittime  - maximum time to wait
 * nettype   - transport type
 */
enum clnt_stat
rpc_broadcast_exp(rpcprog_t prog, rpcvers_t vers, rpcproc_t proc,
    xdrproc_t xargs, caddr_t argsp, xdrproc_t xresults, caddr_t resultsp,
    resultproc_t eachresult, int inittime, int waittime,
    const char *nettype)
{
        enum clnt_stat  stat = RPC_SUCCESS; /* Return status */
        XDR             xdr_stream; /* XDR stream */
        XDR             *xdrs = &xdr_stream;
        struct rpc_msg  msg;    /* RPC message */
        struct timeval  t;
        char            *outbuf = NULL; /* Broadcast msg buffer */
        char            *inbuf = NULL; /* Reply buf */
        int             inlen;
        u_int           maxbufsize = 0;
        AUTH            *sys_auth = authunix_create_default();
        u_int           i;
        void            *handle;
        char            uaddress[1024]; /* A self imposed limit */
        char            *uaddrp = uaddress;
        int             pmap_reply_flag; /* reply recvd from PORTMAP */
        /* An array of all the suitable broadcast transports */
        struct {
                int fd;         /* File descriptor */
                int af;
                int proto;
                struct netconfig *nconf; /* Netconfig structure */
                u_int asize;    /* Size of the addr buf */
                u_int dsize;    /* Size of the data buf */
                struct sockaddr_storage raddr; /* Remote address */
                broadlist_t nal;
        } fdlist[MAXBCAST];
        struct pollfd pfd[MAXBCAST];
        size_t fdlistno = 0;
        struct r_rpcb_rmtcallargs barg; /* Remote arguments */
        struct r_rpcb_rmtcallres bres; /* Remote results */
        size_t outlen;
        struct netconfig *nconf;
        int msec;
        int pollretval;
        int fds_found;

#ifdef PORTMAP
        size_t outlen_pmap = 0;
        u_long port;            /* Remote port number */
        int pmap_flag = 0;      /* UDP exists ? */
        char *outbuf_pmap = NULL;
        struct rmtcallargs barg_pmap;   /* Remote arguments */
        struct rmtcallres bres_pmap; /* Remote results */
        u_int udpbufsz = 0;
#endif                          /* PORTMAP */

        if (sys_auth == NULL) {
                return (RPC_SYSTEMERROR);
        }
        /*
         * initialization: create a fd, a broadcast address, and send the
         * request on the broadcast transport.
         * Listen on all of them and on replies, call the user supplied
         * function.
         */

        if (nettype == NULL)
                nettype = "datagram_n";
        if ((handle = __rpc_setconf(nettype)) == NULL) {
                AUTH_DESTROY(sys_auth);
                return (RPC_UNKNOWNPROTO);
        }
        while ((nconf = __rpc_getconf(handle)) != NULL) {
                int fd;
                struct __rpc_sockinfo si;

                if (nconf->nc_semantics != NC_TPI_CLTS)
                        continue;
                if (fdlistno >= MAXBCAST)
                        break;  /* No more slots available */
                if (!__rpc_nconf2sockinfo(nconf, &si))
                        continue;

                TAILQ_INIT(&fdlist[fdlistno].nal);
                if (__rpc_getbroadifs(si.si_af, si.si_proto, si.si_socktype, 
                    &fdlist[fdlistno].nal) == 0)
                        continue;

                fd = _socket(si.si_af, si.si_socktype, si.si_proto);
                if (fd < 0) {
                        stat = RPC_CANTSEND;
                        continue;
                }
                fdlist[fdlistno].af = si.si_af;
                fdlist[fdlistno].proto = si.si_proto;
                fdlist[fdlistno].fd = fd;
                fdlist[fdlistno].nconf = nconf;
                fdlist[fdlistno].asize = __rpc_get_a_size(si.si_af);
                pfd[fdlistno].events = POLLIN | POLLPRI |
                        POLLRDNORM | POLLRDBAND;
                pfd[fdlistno].fd = fdlist[fdlistno].fd = fd;
                fdlist[fdlistno].dsize = __rpc_get_t_size(si.si_af, si.si_proto,
                                                          0);

                if (maxbufsize <= fdlist[fdlistno].dsize)
                        maxbufsize = fdlist[fdlistno].dsize;

#ifdef PORTMAP
                if (si.si_af == AF_INET && si.si_proto == IPPROTO_UDP) {
                        udpbufsz = fdlist[fdlistno].dsize;
                        outbuf_pmap = reallocf(outbuf_pmap, udpbufsz);
                        if (outbuf_pmap == NULL) {
                                _close(fd);
                                stat = RPC_SYSTEMERROR;
                                goto done_broad;
                        }
                        pmap_flag = 1;
                }
#endif                          /* PORTMAP */
                fdlistno++;
        }

        if (fdlistno == 0) {
                if (stat == RPC_SUCCESS)
                        stat = RPC_UNKNOWNPROTO;
                goto done_broad;
        }
        if (maxbufsize == 0) {
                if (stat == RPC_SUCCESS)
                        stat = RPC_CANTSEND;
                goto done_broad;
        }
        inbuf = malloc(maxbufsize);
        outbuf = malloc(maxbufsize);
        if ((inbuf == NULL) || (outbuf == NULL)) {
                stat = RPC_SYSTEMERROR;
                goto done_broad;
        }

        /* Serialize all the arguments which have to be sent */
        (void) gettimeofday(&t, NULL);
        msg.rm_xid = __RPC_GETXID(&t);
        msg.rm_direction = CALL;
        msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
        msg.rm_call.cb_prog = RPCBPROG;
        msg.rm_call.cb_vers = RPCBVERS;
        msg.rm_call.cb_proc = RPCBPROC_CALLIT;
        barg.prog = prog;
        barg.vers = vers;
        barg.proc = proc;
        barg.args.args_val = argsp;
        barg.xdr_args = xargs;
        bres.addr = uaddrp;
        bres.results.results_val = resultsp;
        bres.xdr_res = xresults;
        msg.rm_call.cb_cred = sys_auth->ah_cred;
        msg.rm_call.cb_verf = sys_auth->ah_verf;
        xdrmem_create(xdrs, outbuf, maxbufsize, XDR_ENCODE);
        if ((!xdr_callmsg(xdrs, &msg)) ||
            (!xdr_rpcb_rmtcallargs(xdrs,
            (struct rpcb_rmtcallargs *)(void *)&barg))) {
                stat = RPC_CANTENCODEARGS;
                goto done_broad;
        }
        outlen = xdr_getpos(xdrs);
        xdr_destroy(xdrs);

#ifdef PORTMAP
        /* Prepare the packet for version 2 PORTMAP */
        if (pmap_flag) {
                msg.rm_xid++;   /* One way to distinguish */
                msg.rm_call.cb_prog = PMAPPROG;
                msg.rm_call.cb_vers = PMAPVERS;
                msg.rm_call.cb_proc = PMAPPROC_CALLIT;
                barg_pmap.prog = prog;
                barg_pmap.vers = vers;
                barg_pmap.proc = proc;
                barg_pmap.args_ptr = argsp;
                barg_pmap.xdr_args = xargs;
                bres_pmap.port_ptr = &port;
                bres_pmap.xdr_results = xresults;
                bres_pmap.results_ptr = resultsp;
                xdrmem_create(xdrs, outbuf_pmap, udpbufsz, XDR_ENCODE);
                if ((! xdr_callmsg(xdrs, &msg)) ||
                    (! xdr_rmtcall_args(xdrs, &barg_pmap))) {
                        stat = RPC_CANTENCODEARGS;
                        goto done_broad;
                }
                outlen_pmap = xdr_getpos(xdrs);
                xdr_destroy(xdrs);
        }
#endif                          /* PORTMAP */

        /*
         * Basic loop: broadcast the packets to transports which
         * support data packets of size such that one can encode
         * all the arguments.
         * Wait a while for response(s).
         * The response timeout grows larger per iteration.
         */
        for (msec = inittime; msec <= waittime; msec += msec) {
                struct broadif *bip;

                /* Broadcast all the packets now */
                for (i = 0; i < fdlistno; i++) {
                        if (fdlist[i].dsize < outlen) {
                                stat = RPC_CANTSEND;
                                continue;
                        }
                        for (bip = TAILQ_FIRST(&fdlist[i].nal); bip != NULL;
                             bip = TAILQ_NEXT(bip, link)) {
                                void *addr;

                                addr = &bip->broadaddr;

                                __rpc_broadenable(fdlist[i].af, fdlist[i].fd,
                                    bip);

                                /*
                                 * Only use version 3 if lowvers is not set
                                 */

                                if (!__rpc_lowvers)
                                        if (_sendto(fdlist[i].fd, outbuf,
                                            outlen, 0, (struct sockaddr*)addr,
                                            (size_t)fdlist[i].asize) !=
                                            outlen) {
#ifdef RPC_DEBUG
                                                perror("sendto");
#endif
                                                warnx("clnt_bcast: cannot send "
                                                      "broadcast packet");
                                                stat = RPC_CANTSEND;
                                                continue;
                                        }
#ifdef RPC_DEBUG
                                if (!__rpc_lowvers)
                                        fprintf(stderr, "Broadcast packet sent "
                                                "for %s\n",
                                                 fdlist[i].nconf->nc_netid);
#endif
#ifdef PORTMAP
                                /*
                                 * Send the version 2 packet also
                                 * for UDP/IP
                                 */
                                if (pmap_flag &&
                                    fdlist[i].proto == IPPROTO_UDP) {
                                        if (_sendto(fdlist[i].fd, outbuf_pmap,
                                            outlen_pmap, 0, addr,
                                            (size_t)fdlist[i].asize) !=
                                                outlen_pmap) {
                                                warnx("clnt_bcast: "
                                                    "Cannot send broadcast packet");
                                                stat = RPC_CANTSEND;
                                                continue;
                                        }
                                }
#ifdef RPC_DEBUG
                                fprintf(stderr, "PMAP Broadcast packet "
                                        "sent for %s\n",
                                        fdlist[i].nconf->nc_netid);
#endif
#endif                          /* PORTMAP */
                        }
                        /* End for sending all packets on this transport */
                }       /* End for sending on all transports */

                if (eachresult == NULL) {
                        stat = RPC_SUCCESS;
                        goto done_broad;
                }

                /*
                 * Get all the replies from these broadcast requests
                 */
        recv_again:

                switch (pollretval = _poll(pfd, fdlistno, msec)) {
                case 0:         /* timed out */
                        stat = RPC_TIMEDOUT;
                        continue;
                case -1:        /* some kind of error - we ignore it */
                        goto recv_again;
                }               /* end of poll results switch */

                for (i = fds_found = 0;
                     i < fdlistno && fds_found < pollretval; i++) {
                        bool_t done = FALSE;

                        if (pfd[i].revents == 0)
                                continue;
                        else if (pfd[i].revents & POLLNVAL) {
                                /*
                                 * Something bad has happened to this descri-
                                 * ptor. We can cause _poll() to ignore
                                 * it simply by using a negative fd.  We do that
                                 * rather than compacting the pfd[] and fdlist[]
                                 * arrays.
                                 */
                                pfd[i].fd = -1;
                                fds_found++;
                                continue;
                        } else
                                fds_found++;
#ifdef RPC_DEBUG
                        fprintf(stderr, "response for %s\n",
                                fdlist[i].nconf->nc_netid);
#endif
                try_again:
                        inlen = _recvfrom(fdlist[i].fd, inbuf, fdlist[i].dsize,
                            0, (struct sockaddr *)(void *)&fdlist[i].raddr,
                            &fdlist[i].asize);
                        if (inlen < 0) {
                                if (errno == EINTR)
                                        goto try_again;
                                warnx("clnt_bcast: Cannot receive reply to "
                                        "broadcast");
                                stat = RPC_CANTRECV;
                                continue;
                        }
                        if (inlen < sizeof (u_int32_t))
                                continue; /* Drop that and go ahead */
                        /*
                         * see if reply transaction id matches sent id.
                         * If so, decode the results. If return id is xid + 1
                         * it was a PORTMAP reply
                         */
                        if (*((u_int32_t *)(void *)(inbuf)) ==
                            *((u_int32_t *)(void *)(outbuf))) {
                                pmap_reply_flag = 0;
                                msg.acpted_rply.ar_verf = _null_auth;
                                msg.acpted_rply.ar_results.where =
                                        (caddr_t)(void *)&bres;
                                msg.acpted_rply.ar_results.proc =
                                        (xdrproc_t)xdr_rpcb_rmtcallres;
#ifdef PORTMAP
                        } else if (pmap_flag &&
                                *((u_int32_t *)(void *)(inbuf)) ==
                                *((u_int32_t *)(void *)(outbuf_pmap))) {
                                pmap_reply_flag = 1;
                                msg.acpted_rply.ar_verf = _null_auth;
                                msg.acpted_rply.ar_results.where =
                                        (caddr_t)(void *)&bres_pmap;
                                msg.acpted_rply.ar_results.proc =
                                        (xdrproc_t)xdr_rmtcallres;
#endif                          /* PORTMAP */
                        } else
                                continue;
                        xdrmem_create(xdrs, inbuf, (u_int)inlen, XDR_DECODE);
                        if (xdr_replymsg(xdrs, &msg)) {
                                if ((msg.rm_reply.rp_stat == MSG_ACCEPTED) &&
                                    (msg.acpted_rply.ar_stat == SUCCESS)) {
                                        struct netbuf taddr, *np;
                                        struct sockaddr_in *sin;

#ifdef PORTMAP
                                        if (pmap_flag && pmap_reply_flag) {
                                                sin = (struct sockaddr_in *)
                                                    (void *)&fdlist[i].raddr;
                                                sin->sin_port =
                                                    htons((u_short)port);
                                                taddr.len = taddr.maxlen = 
                                                    fdlist[i].raddr.ss_len;
                                                taddr.buf = &fdlist[i].raddr;
                                                done = (*eachresult)(resultsp,
                                                    &taddr, fdlist[i].nconf);
                                        } else {
#endif                          /* PORTMAP */
#ifdef RPC_DEBUG
                                                fprintf(stderr, "uaddr %s\n",
                                                    uaddrp);
#endif
                                                np = uaddr2taddr(
                                                    fdlist[i].nconf, uaddrp);
                                                done = (*eachresult)(resultsp,
                                                    np, fdlist[i].nconf);
                                                free(np);
#ifdef PORTMAP
                                        }
#endif                          /* PORTMAP */
                                }
                                /* otherwise, we just ignore the errors ... */
                        }
                        /* else some kind of deserialization problem ... */

                        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;
                        }
                }               /* The recv for loop */
        }                       /* The giant for loop */

done_broad:
        free(inbuf);
        free(outbuf);
#ifdef PORTMAP
        free(outbuf_pmap);
#endif                          /* PORTMAP */
        for (i = 0; i < fdlistno; i++) {
                (void)_close(fdlist[i].fd);
                __rpc_freebroadifs(&fdlist[i].nal);
        }
        AUTH_DESTROY(sys_auth);
        (void) __rpc_endconf(handle);

        return (stat);
}

/*
 * rpc_broadcast()
 *
 * prog       - program number 
 * vers       - version number 
 * proc       - procedure number 
 * xargs      - xdr routine for args 
 * argsp      - pointer to args 
 * xresults   - xdr routine for results 
 * resultsp   - pointer to results 
 * eachresult - call with each result obtained 
 * nettype    - transport type 
 */
enum clnt_stat
rpc_broadcast(rpcprog_t prog, rpcvers_t vers, rpcproc_t proc, xdrproc_t xargs,
    caddr_t argsp, xdrproc_t xresults, caddr_t resultsp,
    resultproc_t eachresult, const char *nettype)
{
        enum clnt_stat  dummy;

        dummy = rpc_broadcast_exp(prog, vers, proc, xargs, argsp,
                xresults, resultsp, eachresult,
                INITTIME, WAITTIME, nettype);
        return (dummy);
}