[openafs.git] / src / ubik / beacon.c

/*
 * Copyright 2000, International Business Machines Corporation and others.
 * All Rights Reserved.
 *
 * This software has been released under the terms of the IBM Public
 * License.  For details, see the LICENSE file in the top-level source
 * directory or online at http://www.openafs.org/dl/license10.html
 */

#include <afsconfig.h>
#include <afs/param.h>

#include <roken.h>

#include <lock.h>
#include <rx/xdr.h>
#include <rx/rx.h>
#include <rx/rxkad.h>
#include <rx/rx_multi.h>
#include <afs/cellconfig.h>
#ifndef AFS_NT40_ENV
#include <afs/afsutil.h>
#include <afs/netutils.h>
#endif

#define UBIK_INTERNALS
#include "ubik.h"
#include "ubik_int.h"

/* These global variables were used to set the function to use to initialise
 * the client security layer. They are retained for backwards compatiblity with
 * legacy callers - the ubik_SetClientSecurityProcs() interface should be used
 * instead
 */
int (*ubik_CRXSecurityProc) (void *rock, struct rx_securityClass **,
                             afs_int32 *);
void *ubik_CRXSecurityRock;

/*! \name statics used to determine if we're the sync site */
static afs_int32 syncSiteUntil = 0;     /*!< valid only if amSyncSite */
int ubik_amSyncSite = 0;        /*!< flag telling if I'm sync site */
static int nServers;            /*!< total number of servers */
static char amIMagic = 0;       /*!< is this host the magic host */
char amIClone = 0;              /*!< is this a clone which doesn't vote */
static char ubik_singleServer = 0;
/*\}*/
static int (*secLayerProc) (void *rock, struct rx_securityClass **,
                            afs_int32 *) = NULL;
static int (*tokenCheckProc) (void *rock) = NULL;
static void * securityRock = NULL;

afs_int32 ubikSecIndex;
struct rx_securityClass *ubikSecClass;
static int ubeacon_InitServerListCommon(afs_uint32 ame,
                                        struct afsconf_cell *info,
                                        char clones[],
                                        afs_uint32 aservers[]);
static int verifyInterfaceAddress(afs_uint32 *ame, struct afsconf_cell *info,
                                  afs_uint32 aservers[]);
static int updateUbikNetworkAddress(afs_uint32 ubik_host[UBIK_MAX_INTERFACE_ADDR]);


/*! \file
 * Module responsible for both deciding if we're currently the sync site,
 * and keeping collecting votes so as to stay sync site.
 *
 * The basic module contacts all of the servers it can, trying to get them to vote
 * for this server for sync site.  The vote request message (called a beacon message)
 * also specifies until which time this site claims to be the sync site, if at all, thus enabling
 * receiving sites to know how long the sync site guarantee is made for.
 *
 * Each  of these beacon messages is thus both a declaration of how long this site will
 * remain sync site, and an attempt to extend that time by collecting votes for a later
 * sync site extension.
 *
 * The voting module is responsible for choosing a reasonable time until which it promises
 * not to vote for someone else.  This parameter (BIG seconds) is not actually passed in
 * the interface (perhaps it should be?) but is instead a compile time constant that both
 * sides know about.

 * The beacon and vote modules work intimately together; the vote module decides how long
 * it should promise the beacon module its vote, and the beacon module takes all of these
 * votes and decides for how long it is the synchronization site.
 */

/*! \brief procedure called from debug rpc call to get this module's state for debugging */
void
ubeacon_Debug(struct ubik_debug *aparm)
{
    /* fill in beacon's state fields in the ubik_debug structure */
    aparm->syncSiteUntil = syncSiteUntil;
    aparm->nServers = nServers;
}

/*!
 * \brief Procedure that determines whether this site has enough current votes to remain sync site.
 *
 * Called from higher-level modules (everything but the vote module).
 *
 * If we're the sync site, check that our guarantees, obtained by the ubeacon_Interact()
 * light-weight process, haven't expired.  We're sync site as long as a majority of the
 * servers in existence have promised us unexpired guarantees.  The variable #ubik_syncSiteUntil
 * contains the time at which the latest of the majority of the sync site guarantees expires
 * (if the variable #ubik_amSyncSite is true)
 * This module also calls up to the recovery module if it thinks that the recovery module
 * may have to pick up a new database (which offucr sif [sic] we lose the sync site votes).
 *
 * \return 1 if local site is the sync site
 * \return 0 if sync site is elsewhere
 */
int
ubeacon_AmSyncSite(void)
{
    afs_int32 now;
    afs_int32 rcode;

    /* special case for fast startup */
    if (nServers == 1 && !amIClone) {
        return 1;               /* one guy is always the sync site */
    }

    if (ubik_amSyncSite == 0 || amIClone)
        rcode = 0;              /* if I don't think I'm the sync site, say so */
    else {
        now = FT_ApproxTime();
        if (syncSiteUntil <= now) {     /* if my votes have expired, say so */
            if (ubik_amSyncSite)
                ubik_dprint("Ubik: I am no longer the sync site\n");
            ubik_amSyncSite = 0;
            rcode = 0;
        } else {
            rcode = 1;          /* otherwise still have the required votes */
        }
    }
    if (rcode == 0)
        urecovery_ResetState(); /* force recovery to re-execute */
    ubik_dprint("beacon: amSyncSite is %d\n", rcode);
    return rcode;
}

/*!
 * \see ubeacon_InitServerListCommon()
 */
int
ubeacon_InitServerListByInfo(afs_uint32 ame, struct afsconf_cell *info,
                             char clones[])
{
    afs_int32 code;

    code = ubeacon_InitServerListCommon(ame, info, clones, 0);
    return code;
}

/*!
 * \param ame "address of me"
 * \param aservers list of other servers
 *
 * \see ubeacon_InitServerListCommon()
 */
int
ubeacon_InitServerList(afs_uint32 ame, afs_uint32 aservers[])
{
    afs_int32 code;

    code =
        ubeacon_InitServerListCommon(ame, (struct afsconf_cell *)0, 0,
                                     aservers);
    return code;
}

void
ubeacon_InitSecurityClass(void)
{
    int i;
    /* get the security index to use, if we can */
    if (secLayerProc) {
        i = (*secLayerProc) (securityRock, &ubikSecClass, &ubikSecIndex);
    } else if (ubik_CRXSecurityProc) {
        i = (*ubik_CRXSecurityProc) (ubik_CRXSecurityRock, &ubikSecClass,
                                     &ubikSecIndex);
    } else
        i = 1;
    if (i) {
        /* don't have sec module yet */
        ubikSecIndex = 0;
        ubikSecClass = rxnull_NewClientSecurityObject();
    }
}

void
ubeacon_ReinitServer(struct ubik_server *ts)
{
    if (tokenCheckProc && !(*tokenCheckProc) (securityRock)) {
        struct rx_connection *disk_rxcid;
        struct rx_connection *vote_rxcid;
        struct rx_connection *tmp;
        ubeacon_InitSecurityClass();
        disk_rxcid =
            rx_NewConnection(rx_HostOf(rx_PeerOf(ts->disk_rxcid)),
                             ubik_callPortal, DISK_SERVICE_ID,
                             ubikSecClass, ubikSecIndex);
        if (disk_rxcid) {
            tmp = ts->disk_rxcid;
            ts->disk_rxcid = disk_rxcid;
            rx_PutConnection(tmp);
        }
        vote_rxcid =
            rx_NewConnection(rx_HostOf(rx_PeerOf(ts->vote_rxcid)),
                             ubik_callPortal, VOTE_SERVICE_ID,
                             ubikSecClass, ubikSecIndex);
        if (vote_rxcid) {
            tmp = ts->vote_rxcid;
            ts->vote_rxcid = vote_rxcid;
            rx_PutConnection(tmp);
        }
    }
}

/*!
 * \brief setup server list
 *
 * \param ame "address of me"
 * \param aservers list of other servers
 *
 * called only at initialization to set up the list of servers to
 * contact for votes.  Just creates the server structure.
 *
 * The "magic" host is the one with the lowest internet address.  It is
 * magic because its vote counts epsilon more than the others.  This acts
 * as a tie-breaker when we have an even number of hosts in the system.
 * For example, if the "magic" host is up in a 2 site system, then it
 * is sync site.  Without the magic host hack, if anyone crashed in a 2
 * site system, we'd be out of business.
 *
 * \note There are two connections in every server structure, one for
 * vote calls (which must always go through quickly) and one for database
 * operations, which are subject to waiting for locks.  If we used only
 * one, the votes would sometimes get held up behind database operations,
 * and the sync site guarantees would timeout even though the host would be
 * up for communication.
 *
 * \see ubeacon_InitServerList(), ubeacon_InitServerListByInfo()
 */
int
ubeacon_InitServerListCommon(afs_uint32 ame, struct afsconf_cell *info,
                             char clones[], afs_uint32 aservers[])
{
    struct ubik_server *ts;
    afs_int32 me = -1;
    afs_int32 servAddr;
    afs_int32 i, code;
    afs_int32 magicHost;
    struct ubik_server *magicServer;

    /* verify that the addresses passed in are correct */
    if ((code = verifyInterfaceAddress(&ame, info, aservers)))
        return code;

    ubeacon_InitSecurityClass();

    magicHost = ntohl(ame);     /* do comparisons in host order */
    magicServer = (struct ubik_server *)0;

    if (info) {
        for (i = 0; i < info->numServers; i++) {
            if (ntohl((afs_uint32) info->hostAddr[i].sin_addr.s_addr) ==
                ntohl((afs_uint32) ame)) {
                me = i;
                if (clones[i]) {
                    amIClone = 1;
                    magicHost = 0;
                }
            }
        }
        nServers = 0;
        for (i = 0; i < info->numServers; i++) {
            if (i == me)
                continue;
            ts = (struct ubik_server *)malloc(sizeof(struct ubik_server));
            memset(ts, 0, sizeof(struct ubik_server));
            ts->next = ubik_servers;
            ubik_servers = ts;
            ts->addr[0] = info->hostAddr[i].sin_addr.s_addr;
            if (clones[i]) {
                ts->isClone = 1;
            } else {
                if (!magicHost
                    || ntohl((afs_uint32) ts->addr[0]) <
                    (afs_uint32) magicHost) {
                    magicHost = ntohl(ts->addr[0]);
                    magicServer = ts;
                }
                ++nServers;
            }
            /* for vote reqs */
            ts->vote_rxcid =
                rx_NewConnection(info->hostAddr[i].sin_addr.s_addr,
                                 ubik_callPortal, VOTE_SERVICE_ID,
                                 ubikSecClass, ubikSecIndex);
            /* for disk reqs */
            ts->disk_rxcid =
                rx_NewConnection(info->hostAddr[i].sin_addr.s_addr,
                                 ubik_callPortal, DISK_SERVICE_ID,
                                 ubikSecClass, ubikSecIndex);
            ts->up = 1;
        }
    } else {
        i = 0;
        while ((servAddr = *aservers++)) {
            if (i >= MAXSERVERS)
                return UNHOSTS; /* too many hosts */
            ts = (struct ubik_server *)malloc(sizeof(struct ubik_server));
            memset(ts, 0, sizeof(struct ubik_server));
            ts->next = ubik_servers;
            ubik_servers = ts;
            ts->addr[0] = servAddr;     /* primary address in  net byte order */
            ts->vote_rxcid = rx_NewConnection(servAddr, ubik_callPortal, VOTE_SERVICE_ID, ubikSecClass, ubikSecIndex);  /* for vote reqs */
            ts->disk_rxcid = rx_NewConnection(servAddr, ubik_callPortal, DISK_SERVICE_ID, ubikSecClass, ubikSecIndex);  /* for disk reqs */
            ts->isClone = 0;    /* don't know about clones */
            ts->up = 1;
            if (ntohl((afs_uint32) servAddr) < (afs_uint32) magicHost) {
                magicHost = ntohl(servAddr);
                magicServer = ts;
            }
            i++;
        }
    }
    if (magicServer)
        magicServer->magic = 1; /* remember for when counting votes */

    if (!amIClone && !magicServer)
        amIMagic = 1;
    if (info) {
        if (!amIClone)
            ++nServers;         /* count this server as well as the remotes */
    } else
        nServers = i + 1;       /* count this server as well as the remotes */

    ubik_quorum = (nServers >> 1) + 1;  /* compute the majority figure */
    /* send addrs to all other servers */
    code = updateUbikNetworkAddress(ubik_host);
    if (code)
        return code;

/* Shoud we set some defaults for RX??
    r_retryInterval = 2;
    r_nRetries = (RPCTIMEOUT/r_retryInterval);
*/
    if (info) {
        if (!ubik_servers)      /* special case 1 server */
            ubik_singleServer = 1;
        if (nServers == 1 && !amIClone) {
            ubik_amSyncSite = 1;        /* let's start as sync site */
            syncSiteUntil = 0x7fffffff; /* and be it quite a while */
        }
    } else {
        if (nServers == 1)      /* special case 1 server */
            ubik_singleServer = 1;
    }

    if (ubik_singleServer) {
        if (!ubik_amSyncSite)
            ubik_dprint("Ubik: I am the sync site - 1 server\n");
        ubik_amSyncSite = 1;
        syncSiteUntil = 0x7fffffff;     /* quite a while */
    }
    return 0;
}

/*!
 * \brief main lwp loop for code that sends out beacons.
 *
 * This code only runs while we're sync site or we want to be the sync site.
 * It runs in its very own light-weight process.
 */
void *
ubeacon_Interact(void *dummy)
{
    afs_int32 code;
    struct timeval tt;
    struct rx_connection *connections[MAXSERVERS];
    struct ubik_server *servers[MAXSERVERS];
    afs_int32 i;
    struct ubik_server *ts;
    afs_int32 temp, yesVotes, lastWakeupTime, oldestYesVote, syncsite;
    struct ubik_tid ttid;
    afs_int32 startTime;

    /* loop forever getting votes */
    lastWakeupTime = 0;         /* keep track of time we last started a vote collection */
    while (1) {

        /* don't wakeup more than every POLLTIME seconds */
        temp = (lastWakeupTime + POLLTIME) - FT_ApproxTime();
        /* don't sleep if last collection phase took too long (probably timed someone out ) */
        if (temp > 0) {
            if (temp > POLLTIME)
                temp = POLLTIME;
            tt.tv_sec = temp;
            tt.tv_usec = 0;
#ifdef AFS_PTHREAD_ENV
            code = select(0, 0, 0, 0, &tt);
#else
            code = IOMGR_Select(0, 0, 0, 0, &tt);
#endif
        } else
            code = 0;

        lastWakeupTime = FT_ApproxTime();       /* started a new collection phase */

        if (ubik_singleServer)
            continue;           /* special-case 1 server for speedy startup */

        if (!uvote_ShouldIRun())
            continue;           /* if voter has heard from a better candidate than us, don't bother running */

        /* otherwise we should run for election, or we're the sync site (and have already won);
         * send out the beacon packets */
        /* build list of all up hosts (noticing dead hosts are running again
         * is a task for the recovery module, not the beacon module), and
         * prepare to send them an r multi-call containing the beacon message */
        i = 0;                  /* collect connections */
        for (ts = ubik_servers; ts; ts = ts->next) {
            if (ts->up && ts->addr[0] != ubik_host[0]) {
                servers[i] = ts;
                connections[i++] = ts->vote_rxcid;
            }
        }
        servers[i] = (struct ubik_server *)0;   /* end of list */
        /* note that we assume in the vote module that we'll always get at least BIGTIME
         * seconds of vote from anyone who votes for us, which means we can conservatively
         * assume we'll be fine until SMALLTIME seconds after we start collecting votes */
        /* this next is essentially an expansion of rgen's ServBeacon routine */

        ttid.epoch = ubik_epochTime;
        if (ubik_dbase->flags & DBWRITING) {
            /*
             * if a write is in progress, we have to send the writeTidCounter
             * which holds the tid counter of the write transaction , and not
             * send the tidCounter value which holds the tid counter of the
             * last transaction.
             */
            ttid.counter = ubik_dbase->writeTidCounter;
        } else
            ttid.counter = ubik_dbase->tidCounter + 1;

        /* now analyze return codes, counting up our votes */
        yesVotes = 0;           /* count how many to ensure we have quorum */
        oldestYesVote = 0x7fffffff;     /* time quorum expires */
        syncsite = ubeacon_AmSyncSite();
        startTime = FT_ApproxTime();
        /*
         * Don't waste time using mult Rx calls if there are no connections out there
         */
        if (i > 0) {
            char hoststr[16];
            multi_Rx(connections, i) {
                multi_VOTE_Beacon(syncsite, startTime, &ubik_dbase->version,
                                  &ttid);
                temp = FT_ApproxTime(); /* now, more or less */
                ts = servers[multi_i];
                ts->lastBeaconSent = temp;
                code = multi_error;
                /* note that the vote time (the return code) represents the time
                 * the vote was computed, *not* the time the vote expires.  We compute
                 * the latter down below if we got enough votes to go with */
                if (code > 0) {
                    if ((code & ~0xff) == ERROR_TABLE_BASE_RXK) {
                        ubik_dprint("token error %d from host %s\n",
                                    code, afs_inet_ntoa_r(ts->addr[0], hoststr));
                        ts->up = 0;
                        ts->beaconSinceDown = 0;
                        urecovery_LostServer(ts);
                    } else {
                        ts->lastVoteTime = code;
                        if (code < oldestYesVote)
                            oldestYesVote = code;
                        ts->lastVote = 1;
                        if (!ts->isClone)
                            yesVotes += 2;
                        if (ts->magic)
                            yesVotes++; /* the extra epsilon */
                        ts->up = 1;     /* server is up (not really necessary: recovery does this for real) */
                        ts->beaconSinceDown = 1;
                        ubik_dprint("yes vote from host %s\n",
                                    afs_inet_ntoa_r(ts->addr[0], hoststr));
                    }
                } else if (code == 0) {
                    ts->lastVoteTime = temp;
                    ts->lastVote = 0;
                    ts->beaconSinceDown = 1;
                    ubik_dprint("no vote from %s\n",
                                afs_inet_ntoa_r(ts->addr[0], hoststr));
                } else if (code < 0) {
                    ts->up = 0;
                    ts->beaconSinceDown = 0;
                    urecovery_LostServer(ts);
                    ubik_dprint("time out from %s\n",
                                afs_inet_ntoa_r(ts->addr[0], hoststr));
                }
            }
            multi_End;
        }
        /* now call our own voter module to see if we'll vote for ourself.  Note that
         * the same restrictions apply for our voting for ourself as for our voting
         * for anyone else. */
        i = SVOTE_Beacon((struct rx_call *)0, ubeacon_AmSyncSite(), startTime,
                         &ubik_dbase->version, &ttid);
        if (i) {
            yesVotes += 2;
            if (amIMagic)
                yesVotes++;     /* extra epsilon */
            if (i < oldestYesVote)
                oldestYesVote = i;
        }

        /* now decide if we have enough votes to become sync site.
         * Note that we can still get enough votes even if we didn't for ourself. */
        if (yesVotes > nServers) {      /* yesVotes is bumped by 2 or 3 for each site */
            if (!ubik_amSyncSite)
                ubik_dprint("Ubik: I am the sync site\n");
            ubik_amSyncSite = 1;
            syncSiteUntil = oldestYesVote + SMALLTIME;
#ifndef AFS_PTHREAD_ENV
                /* I did not find a corresponding LWP_WaitProcess(&ubik_amSyncSite) --
                   this may be a spurious signal call -- sjenkins */
                LWP_NoYieldSignal(&ubik_amSyncSite);
#endif
        } else {
            if (ubik_amSyncSite)
                ubik_dprint("Ubik: I am no longer the sync site\n");
            ubik_amSyncSite = 0;
            urecovery_ResetState();     /* tell recovery we're no longer the sync site */
        }

    }                           /* while loop */
    return NULL;
}

/*!
 * \brief Verify that a given IP addresses does actually exist on this machine.
 *
 * \param ame      the pointer to my IP address specified in the
 *                 CellServDB file.
 * \param aservers an array containing IP
 *                 addresses of remote ubik servers. The array is
 *                 terminated by a zero address.
 *
 * Algorithm     : Verify that my IP addresses \p ame does actually exist
 *                 on this machine.  If any of my IP addresses are there
 *                 in the remote server list \p aserver, remove them from
 *                 this list.  Update global variable \p ubik_host[] with
 *                 my IP addresses.
 *
 * \return 0 on success, non-zero on failure
 */
static int
verifyInterfaceAddress(afs_uint32 *ame, struct afsconf_cell *info,
                       afs_uint32 aservers[]) {
    afs_uint32 myAddr[UBIK_MAX_INTERFACE_ADDR], *servList, tmpAddr;
    afs_uint32 myAddr2[UBIK_MAX_INTERFACE_ADDR];
    char hoststr[16];
    int tcount, count, found, i, j, totalServers, start, end, usednetfiles =
        0;

    if (info)
        totalServers = info->numServers;
    else {                      /* count the number of servers */
        for (totalServers = 0, servList = aservers; *servList; servList++)
            totalServers++;
    }

    if (AFSDIR_SERVER_NETRESTRICT_FILEPATH || AFSDIR_SERVER_NETINFO_FILEPATH) {
        /*
         * Find addresses we are supposed to register as per the netrestrict file
         * if it exists, else just register all the addresses we find on this
         * host as returned by rx_getAllAddr (in NBO)
         */
        char reason[1024];
        count =
            parseNetFiles(myAddr, NULL, NULL, UBIK_MAX_INTERFACE_ADDR, reason,
                          AFSDIR_SERVER_NETINFO_FILEPATH,
                          AFSDIR_SERVER_NETRESTRICT_FILEPATH);
        if (count < 0) {
            ubik_print("ubik: Can't register any valid addresses:%s\n",
                       reason);
            ubik_print("Aborting..\n");
            return UBADHOST;
        }
        usednetfiles++;
    } else {
        /* get all my interface addresses in net byte order */
        count = rx_getAllAddr(myAddr, UBIK_MAX_INTERFACE_ADDR);
    }

    if (count <= 0) {           /* no address found */
        ubik_print("ubik: No network addresses found, aborting..");
        return UBADHOST;
    }

    /* verify that the My-address passed in by ubik is correct */
    for (j = 0, found = 0; j < count; j++) {
        if (*ame == myAddr[j]) {        /* both in net byte order */
            found = 1;
            break;
        }
    }

    if (!found) {
        ubik_print("ubik: primary address %s does not exist\n",
                   afs_inet_ntoa_r(*ame, hoststr));
        /* if we had the result of rx_getAllAddr already, avoid subverting
         * the "is gethostbyname(gethostname()) us" check. If we're
         * using NetInfo/NetRestrict, we assume they have enough clue
         * to avoid that big hole in their foot from the loaded gun. */
        if (usednetfiles) {
            /* take the address we did get, then see if ame was masked */
            *ame = myAddr[0];
            tcount = rx_getAllAddr(myAddr2, UBIK_MAX_INTERFACE_ADDR);
            if (tcount <= 0) {  /* no address found */
                ubik_print("ubik: No network addresses found, aborting..");
                return UBADHOST;
            }

            /* verify that the My-address passed in by ubik is correct */
            for (j = 0, found = 0; j < tcount; j++) {
                if (*ame == myAddr2[j]) {       /* both in net byte order */
                    found = 1;
                    break;
                }
            }
        }
        if (!found)
            return UBADHOST;
    }

    /* if any of my addresses are there in serverList, then
     ** use that as my primary addresses : the higher level
     ** application screwed up in dealing with multihomed concepts
     */
    for (j = 0, found = 0; j < count; j++) {
        for (i = 0; i < totalServers; i++) {
            if (info)
                tmpAddr = (afs_uint32) info->hostAddr[i].sin_addr.s_addr;
            else
                tmpAddr = aservers[i];
            if (myAddr[j] == tmpAddr) {
                *ame = tmpAddr;
                if (!info)
                    aservers[i] = 0;
                found = 1;
            }
        }
    }
    if (found)
        ubik_print("Using %s as my primary address\n", afs_inet_ntoa_r(*ame, hoststr));

    if (!info) {
        /* get rid of servers which were purged because all
         ** those interface addresses are myself
         */
        for (start = 0, end = totalServers - 1; (start < end); start++, end--) {
            /* find the first zero entry from the beginning */
            for (; (start < end) && (aservers[start]); start++);

            /* find the last non-zero entry from the end */
            for (; (end >= 0) && (!aservers[end]); end--);

            /* if there is nothing more to purge, exit from loop */
            if (start >= end)
                break;

            /* move the entry */
            aservers[start] = aservers[end];
            aservers[end] = 0;  /* this entry was moved */
        }
    }

    /* update all my addresses in ubik_host in such a way
     ** that ubik_host[0] has the primary address
     */
    ubik_host[0] = *ame;
    for (j = 0, i = 1; j < count; j++)
        if (*ame != myAddr[j])
            ubik_host[i++] = myAddr[j];

    return 0;                   /* return success */
}


/*!
 * \brief Exchange IP address information with remote servers.
 *
 * \param ubik_host an array containing all my IP addresses.
 *
 * Algorithm     : Do an RPC to all remote ubik servers infroming them
 *                 about my IP addresses. Get their IP addresses and
 *                 update my linked list of ubik servers \p ubik_servers
 *
 * \return 0 on success, non-zero on failure
 */
static int
updateUbikNetworkAddress(afs_uint32 ubik_host[UBIK_MAX_INTERFACE_ADDR])
{
    int j, count, code = 0;
    UbikInterfaceAddr inAddr, outAddr;
    struct rx_connection *conns[MAXSERVERS];
    struct ubik_server *ts, *server[MAXSERVERS];
    char buffer[32];
    char hoststr[16];

    for (count = 0, ts = ubik_servers; ts; count++, ts = ts->next) {
        conns[count] = ts->disk_rxcid;
        server[count] = ts;
    }


    /* inform all other servers only if there are more than one
     * database servers in the cell */

    if (count > 0) {

        for (j = 0; j < UBIK_MAX_INTERFACE_ADDR; j++)
            inAddr.hostAddr[j] = ntohl(ubik_host[j]);


        /* do the multi-RX RPC to all other servers */
        multi_Rx(conns, count) {
            multi_DISK_UpdateInterfaceAddr(&inAddr, &outAddr);
            ts = server[multi_i];       /* reply received from this server */
            if (!multi_error) {
                if (ts->addr[0] != htonl(outAddr.hostAddr[0])) {
                    code = UBADHOST;
                    strcpy(buffer, afs_inet_ntoa_r(ts->addr[0], hoststr));
                    ubik_print("ubik:Two primary addresses for same server \
                    %s %s\n", buffer,
                    afs_inet_ntoa_r(htonl(outAddr.hostAddr[0]), hoststr));
                } else {
                    for (j = 1; j < UBIK_MAX_INTERFACE_ADDR; j++)
                        ts->addr[j] = htonl(outAddr.hostAddr[j]);
                }
            } else if (multi_error == RXGEN_OPCODE) {   /* pre 3.5 remote server */
                ubik_print
                    ("ubik server %s does not support UpdateInterfaceAddr RPC\n",
                     afs_inet_ntoa_r(ts->addr[0], hoststr));
            } else if (multi_error == UBADHOST) {
                code = UBADHOST;        /* remote CellServDB inconsistency */
                ubik_print("Inconsistent Cell Info on server: ");
                for (j = 0; j < UBIK_MAX_INTERFACE_ADDR && ts->addr[j]; j++)
                    ubik_print("%s ", afs_inet_ntoa_r(ts->addr[j], hoststr));
                ubik_print("\n");
            } else {
                ts->up = 0;     /* mark the remote server as down */
            }
        }
        multi_End;
    }
    return code;
}

void
ubik_SetClientSecurityProcs(int (*secproc) (void *,
                                            struct rx_securityClass **,
                                            afs_int32 *),
                            int (*checkproc) (void *),
                            void *rock)
{
    secLayerProc = secproc;
    tokenCheckProc = checkproc;
    securityRock = rock;
}