kde-workspace/kdm/backend/choose.c

/*

Copyright 1990, 1998  The Open Group
Copyright 2002-2004 Oswald Buddenhagen <ossi@kde.org>

Permission to use, copy, modify, distribute, and sell this software and its
documentation for any purpose is hereby granted without fee, provided that
the above copyright notice appear in all copies and that both that
copyright notice and this permission notice appear in supporting
documentation.

The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.

Except as contained in this notice, the name of a copyright holder shall
not be used in advertising or otherwise to promote the sale, use or
other dealings in this Software without prior written authorization
from the copyright holder.

*/

/*
 * xdm - display manager daemon
 * Author: Keith Packard, MIT X Consortium
 *
 * chooser backend
 */

#include "dm.h"
#include "dm_error.h"
#include "dm_socket.h"

#include <ctype.h>
#include <sys/ioctl.h>
#ifdef HAVE_SYS_SOCKIO_H
# include <sys/sockio.h>
#endif
#ifndef __GNU__
# include <net/if.h>
#endif
#include <arpa/inet.h>
#include <netdb.h>

#ifdef STREAMSCONN
# include <stropts.h>
# include <tiuser.h>
# include <netconfig.h>
# include <netdir.h>
#endif

typedef struct _Choices {
    struct _Choices *next;
    ARRAY8 client;
    ARRAY8 port;
    CARD16 connectionType;
    ARRAY8 choice;
    time_t timeout;
} ChoiceRec, *ChoicePtr;

static ChoicePtr choices;

time_t
disposeIndirectHosts()
{
    ChoicePtr c;

    while (choices) {
        if (choices->timeout > now)
            return choices->timeout;
        debug("timing out indirect host\n");
        c = choices;
        choices = c->next;
        XdmcpDisposeARRAY8(&c->client);
        XdmcpDisposeARRAY8(&c->port);
        XdmcpDisposeARRAY8(&c->choice);
        free(c);
    }
    return TO_INF;
}

ARRAY8Ptr
indirectChoice(ARRAY8Ptr clientAddress, ARRAY8Ptr clientPort,
               CARD16 connectionType)
{
    ChoicePtr c;

    debug("have indirect choice?\n");
    for (c = choices; c; c = c->next)
        if (XdmcpARRAY8Equal(clientAddress, &c->client) &&
            XdmcpARRAY8Equal(clientPort, &c->port) &&
            connectionType == c->connectionType)
        {
            debug(c->choice.data ? "  yes\n" : "  not yet\n");
            return c->choice.data ? &c->choice : 0;
        }
    debug("  host not registered\n");
    return 0;
}

int
checkIndirectChoice(ARRAY8Ptr clientAddress, ARRAY8Ptr clientPort,
                    CARD16 connectionType)
{
    ChoicePtr c, *cp;
    int uc;

    debug("checkIndirectChoice\n");
    for (cp = &choices; (c = *cp); cp = &c->next) {
        if (XdmcpARRAY8Equal(clientAddress, &c->client) &&
            XdmcpARRAY8Equal(clientPort, &c->port) &&
            connectionType == c->connectionType)
        {
            *cp = c->next;
            if (c->choice.data) {
                XdmcpDisposeARRAY8(&c->choice);
                debug("  choice already made\n");
                uc = False;
            } else {
                uc = True;
            }
            XdmcpDisposeARRAY8(&c->port);
            XdmcpDisposeARRAY8(&c->client);
            free(c);
            return uc;
        }
    }
    debug("  host not registered\n");
    return False;
}

void
registerIndirectChoice(ARRAY8Ptr clientAddress, ARRAY8Ptr clientPort,
                       CARD16 connectionType, ARRAY8Ptr choice)
{
    ChoicePtr c, *cp;

    debug("registering indirect %s\n", choice ? "choice" : "client");
    for (cp = &choices; (c = *cp); cp = &c->next) {
        if (XdmcpARRAY8Equal(clientAddress, &c->client) &&
            XdmcpARRAY8Equal(clientPort, &c->port) &&
            connectionType == c->connectionType)
        {
            *cp = c->next;
            while (*cp)
                cp = &(*cp)->next;
            if (choice)
                XdmcpDisposeARRAY8(&c->choice);
            debug("  replacing existing\n");
            goto found;
        }
    }

    if (!(c = Malloc(sizeof(ChoiceRec))))
        return;
    if (!XdmcpCopyARRAY8(clientAddress, &c->client)) {
        free(c);
        return;
    }
    if (!XdmcpCopyARRAY8(clientPort, &c->port)) {
        XdmcpDisposeARRAY8(&c->client);
        free(c);
        return;
    }
    c->connectionType = connectionType;
    c->choice.data = 0;
  found:
    if (choice && !XdmcpCopyARRAY8(choice, &c->choice)) {
        XdmcpDisposeARRAY8(&c->port);
        XdmcpDisposeARRAY8(&c->client);
        free(c);
        return;
    }
    c->timeout = now + choiceTimeout;
    c->next = 0;
    *cp = c;
}


/* ####################### */


typedef struct _HostAddr {
    struct _HostAddr *next;
    struct sockaddr *addr;
    int addrlen;
    xdmOpCode type;
} HostAddr;

static HostAddr *hostAddrdb;

typedef struct _HostName {
    struct _HostName *next;
    unsigned willing:1, alive:1;
    ARRAY8 hostname, status;
    CARD16 connectionType;
    ARRAY8 hostaddr;
} HostName;

static HostName *hostNamedb;

static XdmcpBuffer directBuffer, broadcastBuffer;
static XdmcpBuffer buffer;

static int socketFD;
#if defined(IPv6) && defined(AF_INET6)
static int socket6FD;
#endif


static void
doPingHosts()
{
    HostAddr *hosts;

    for (hosts = hostAddrdb; hosts; hosts = hosts->next)
#if defined(IPv6) && defined(AF_INET6)
        XdmcpFlush(hosts->addr->sa_family == AF_INET6 ? socket6FD : socketFD,
#else
        XdmcpFlush(socketFD,
#endif
                   hosts->type == QUERY ? &directBuffer : &broadcastBuffer,
                   (XdmcpNetaddr)hosts->addr, hosts->addrlen);
}

static int
addHostname(ARRAY8Ptr hostname, ARRAY8Ptr status,
            struct sockaddr *addr, int will)
{
    HostName **names, *name;
    ARRAY8 hostAddr;
    CARD16 connectionType;

    switch (addr->sa_family) {
    case AF_INET:
        hostAddr.data = (CARD8 *)&((struct sockaddr_in *)addr)->sin_addr;
        hostAddr.length = 4;
        connectionType = FamilyInternet;
        break;
#if defined(IPv6) && defined(AF_INET6)
    case AF_INET6:
        hostAddr.data = (CARD8 *)&((struct sockaddr_in6 *)addr)->sin6_addr;
        hostAddr.length = 16;
        connectionType = FamilyInternet6;
        break;
#endif
    default:
        hostAddr.data = (CARD8 *)"";
        hostAddr.length = 0;
        connectionType = FamilyLocal;
        break;
    }
    for (names = &hostNamedb; *names; names = &(*names)->next) {
        name = *names;
        if (connectionType == name->connectionType &&
            XdmcpARRAY8Equal(&hostAddr, &name->hostaddr))
        {
            if (XdmcpARRAY8Equal(status, &name->status))
                return False;
            XdmcpDisposeARRAY8(&name->status);
            XdmcpDisposeARRAY8(hostname);

            gSendInt(G_Ch_ChangeHost);
            goto gotold;
        }
    }
    if (!(name = Malloc(sizeof(*name))))
        return False;
    if (hostname->length) {
        switch (addr->sa_family) {
        case AF_INET:
#if defined(IPv6) && defined(AF_INET6)
        case AF_INET6:
#endif
            {
                struct hostent *hostent;
                char *host;

                hostent = gethostbyaddr((char *)hostAddr.data,
                                        hostAddr.length, addr->sa_family);
                if (hostent) {
                    XdmcpDisposeARRAY8(hostname);
                    host = hostent->h_name;
                    XdmcpAllocARRAY8(hostname, strlen(host));
                    memmove(hostname->data, host, hostname->length);
                }
            }
        }
    }
    if (!XdmcpAllocARRAY8(&name->hostaddr, hostAddr.length)) {
        free(name);
        return False;
    }
    memmove(name->hostaddr.data, hostAddr.data, hostAddr.length);
    name->connectionType = connectionType;
    name->hostname = *hostname;

    *names = name;
    name->next = 0;

    gSendInt(G_Ch_AddHost);
  gotold:
    name->alive = True;
    name->willing = will;
    name->status = *status;

    gSendInt((int)(long)name); /* just an id */
    gSendNStr((char *)name->hostname.data, name->hostname.length);
    gSendNStr((char *)name->status.data, name->status.length);
    gSendInt(will);

    return True;
}

static void
disposeHostname(HostName *host)
{
    XdmcpDisposeARRAY8(&host->hostname);
    XdmcpDisposeARRAY8(&host->hostaddr);
    XdmcpDisposeARRAY8(&host->status);
    free(host);
}

static void
emptyHostnames(void)
{
    HostName *host, *nhost;

    for (host = hostNamedb; host; host = nhost) {
        nhost = host->next;
        disposeHostname(host);
    }
    hostNamedb = 0;
}

static void
receivePacket(int sfd)
{
    XdmcpHeader header;
    ARRAY8 authenticationName;
    ARRAY8 hostname;
    ARRAY8 status;
    int saveHostname = False;
#if defined(IPv6) && defined(AF_INET6)
    struct sockaddr_storage addr;
#else
    struct sockaddr addr;
#endif
    int addrlen;

    addrlen = sizeof(addr);
    if (!XdmcpFill(sfd, &buffer, (XdmcpNetaddr)&addr, &addrlen))
        return;
    if (!XdmcpReadHeader(&buffer, &header))
        return;
    if (header.version != XDM_PROTOCOL_VERSION)
        return;
    hostname.data = 0;
    status.data = 0;
    authenticationName.data = 0;
    switch (header.opcode) {
    case WILLING:
        if (XdmcpReadARRAY8(&buffer, &authenticationName) &&
            XdmcpReadARRAY8(&buffer, &hostname) &&
            XdmcpReadARRAY8(&buffer, &status))
        {
            if (header.length == 6 + authenticationName.length +
                                 hostname.length + status.length)
                if (addHostname(&hostname, &status,
                                (struct sockaddr *)&addr, True))
                    saveHostname = True;
        }
        XdmcpDisposeARRAY8(&authenticationName);
        break;
    case UNWILLING:
        if (XdmcpReadARRAY8(&buffer, &hostname) &&
            XdmcpReadARRAY8(&buffer, &status))
        {
            if (header.length == 4 + hostname.length + status.length)
                if (addHostname(&hostname, &status,
                                (struct sockaddr *)&addr, False))
                    saveHostname = True;
        }
        break;
    default:
        break;
    }
    if (!saveHostname) {
        XdmcpDisposeARRAY8(&hostname);
        XdmcpDisposeARRAY8(&status);
    }
}

static void
addHostaddr(HostAddr **hosts, struct sockaddr *addr, int len, xdmOpCode type)
{
    HostAddr *host;

    debug("adding host %[*hhu, type %d\n", len, addr, type);
    for (host = *hosts; host; host = host->next)
        if (host->type == type && host->addr->sa_family == addr->sa_family)
            switch (addr->sa_family) {
            case AF_INET: {
                struct sockaddr_in *na = (struct sockaddr_in *)addr;
                struct sockaddr_in *oa = (struct sockaddr_in *)host->addr;
                if (na->sin_port == oa->sin_port &&
                        na->sin_addr.s_addr == oa->sin_addr.s_addr)
                    return;
                break; }
#if defined(IPv6) && defined(AF_INET6)
            case AF_INET6: {
                struct sockaddr_in6 *na = (struct sockaddr_in6 *)addr;
                struct sockaddr_in6 *oa = (struct sockaddr_in6 *)host->addr;
                if (na->sin6_port == oa->sin6_port &&
                        !memcmp(&na->sin6_addr, &oa->sin6_addr, 16))
                    return;
                break; }
#endif
            default: /* ... */
                break;
            }
    debug(" not dupe\n");
    if (!(host = Malloc(sizeof(*host))))
        return;
    if (!(host->addr = Malloc(len))) {
        free(host);
        return;
    }
    memcpy(host->addr, addr, len);
    host->addrlen = len;
    host->type = type;
    host->next = *hosts;
    *hosts = host;
}

static void
registerHostaddr(struct sockaddr *addr, int len, xdmOpCode type)
{
    addHostaddr(&hostAddrdb, addr, len, type);
}

static void
emptyPingHosts(void)
{
    HostAddr *host, *nhost;

    for (host = hostAddrdb; host; host = nhost) {
        nhost = host->next;
        free(host->addr);
        free(host);
    }
    hostAddrdb = 0;
}

/* Handle variable length ifreq in BNR2 and later */
#ifdef VARIABLE_IFREQ
# define ifr_size(p) \
    (sizeof(struct ifreq) + \
     (p->ifr_addr.sa_len > sizeof (p->ifr_addr) ? \
      p->ifr_addr.sa_len - sizeof (p->ifr_addr) : 0))
#else
# define ifr_size(p) (sizeof(struct ifreq))
#endif

#define IFC_REQ(ifc) ifc.ifc_req

static void
registerBroadcastForPing(void)
{
    struct sockaddr_in in_addr;

#ifdef __GNU__
    in_addr.sin_addr.s_addr = htonl(0xFFFFFFFF);
    in_addr.sin_port = htons(XDM_UDP_PORT);
    registerHostaddr((struct sockaddr *)&in_addr, sizeof(in_addr),
                     BROADCAST_QUERY);
#else /* __GNU__ */
    struct ifconf ifc;
    register struct ifreq *ifr;
    struct sockaddr broad_addr;
    char buf[2048], *cp, *cplim;
    ifc.ifc_len = sizeof(buf);
    ifc.ifc_buf = buf;
    if (ioctl(socketFD, (int)SIOCGIFCONF, (char *)&ifc) < 0)
        return;

    cplim = (char *)IFC_REQ(ifc) + ifc.ifc_len;

    for (cp = (char *)IFC_REQ(ifc); cp < cplim; cp += ifr_size(ifr))
    {
        ifr = (struct ifreq *)cp;
        if (ifr->ifr_addr.sa_family != AF_INET)
            continue;

        broad_addr = ifr->ifr_addr;
        ((struct sockaddr_in *)&broad_addr)->sin_addr.s_addr =
            htonl(INADDR_BROADCAST);
# ifdef SIOCGIFBRDADDR
        {
            struct ifreq broad_req;

            broad_req = *ifr;
            if (ioctl(socketFD, SIOCGIFFLAGS, (char *)&broad_req) != -1 &&
                    (broad_req.ifr_flags & IFF_BROADCAST) &&
                    (broad_req.ifr_flags & IFF_UP))
            {
                broad_req = *ifr;
                if (ioctl(socketFD, SIOCGIFBRDADDR, (char *)&broad_req) != -1)
                    broad_addr = broad_req.ifr_addr;
                else
                    continue;
            } else
                continue;
        }
# endif
        in_addr = *((struct sockaddr_in *)&broad_addr);
        in_addr.sin_port = htons(XDM_UDP_PORT);
# ifdef HAVE_STRUCT_SOCKADDR_IN_SIN_LEN
        in_addr.sin_len = sizeof(in_addr);
# endif
        registerHostaddr((struct sockaddr *)&in_addr, sizeof(in_addr),
                         BROADCAST_QUERY);
    }
#endif
}

static int
makeSockAddrs(const char *name, HostAddr **hosts)
{
#if defined(IPv6) && defined(AF_INET6)
    struct addrinfo *ai, *nai, hints;
    bzero(&hints, sizeof(hints));
    hints.ai_socktype = SOCK_DGRAM;
    if (getaddrinfo(name, stringify(XDM_UDP_PORT), &hints, &ai))
        return False;
    for (nai = ai; nai; nai = nai->ai_next)
        if ((nai->ai_family == AF_INET) || (nai->ai_family == AF_INET6))
            addHostaddr(hosts, nai->ai_addr, nai->ai_addrlen,
                        (nai->ai_family == AF_INET ?
                         IN_MULTICAST(((struct sockaddr_in *)nai->ai_addr)->sin_addr.s_addr) :
                         IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6 *)nai->ai_addr)->sin6_addr)) ?
                        BROADCAST_QUERY : QUERY);
#else
    struct sockaddr_in in_addr;
    /* Per RFC 1123, check first for IP address in dotted-decimal form */
    if ((in_addr.sin_addr.s_addr = inet_addr(name)) == (unsigned)-1) {
        struct hostent *hostent;
        if (!(hostent = gethostbyname(name)) ||
                hostent->h_addrtype != AF_INET)
            return False;
        memcpy(&in_addr.sin_addr, hostent->h_addr, 4);
    }
    in_addr.sin_family = AF_INET;
    in_addr.sin_port = htons(XDM_UDP_PORT);
# ifdef HAVE_STRUCT_SOCKADDR_IN_SIN_LEN
    in_addr.sin_len = sizeof(in_addr);
# endif
    addHostaddr(hosts, (struct sockaddr *)&in_addr, sizeof(in_addr),
# ifdef IN_MULTICAST
                IN_MULTICAST(in_addr.sin_addr.s_addr) ?
                BROADCAST_QUERY :
# endif
                QUERY);
#endif
    return True;
}

/*
 * Register the address for this host.
 * Called for interactively specified hosts.
 * The special names "BROADCAST" and "*" look up all the broadcast
 *  addresses on the local host.
 */

static int
registerForPing(const char *name)
{
    debug("manual host registration: %s\n", name);
    if (!strcmp(name, "BROADCAST") || !strcmp(name, "*"))
        registerBroadcastForPing();
    else if (!makeSockAddrs(name, &hostAddrdb))
        return False;
    return True;
}

/*ARGSUSED*/
static void
addChooserHost(CARD16 connectionType,
               ARRAY8Ptr addr,
               char *closure ATTR_UNUSED)
{
    if (connectionType == FamilyBroadcast) {
        registerBroadcastForPing();
        return;
    }
    debug("internal host registration: %[*hhu, family %hx\n",
          addr->length, addr->data, connectionType);
    if (connectionType == FamilyInternet) {
        struct sockaddr_in in_addr;
        in_addr.sin_family = AF_INET;
        memmove(&in_addr.sin_addr, addr->data, 4);
        in_addr.sin_port = htons(XDM_UDP_PORT);
#ifdef HAVE_STRUCT_SOCKADDR_IN_SIN_LEN
        in_addr.sin_len = sizeof(in_addr);
#endif
        registerHostaddr((struct sockaddr *)&in_addr, sizeof(in_addr),
#ifdef IN_MULTICAST
                         IN_MULTICAST(in_addr.sin_addr.s_addr) ?
                         BROADCAST_QUERY :
#endif
                         QUERY);
#if defined(IPv6) && defined(AF_INET6)
    } else if (connectionType == FamilyInternet6) {
        struct sockaddr_in6 in6_addr;
        in6_addr.sin6_family = AF_INET6;
        memmove(&in6_addr.sin6_addr, addr->data, 16);
        in6_addr.sin6_port = htons(XDM_UDP_PORT);
#ifdef HAVE_STRUCT_SOCKADDR_IN6_SIN6_LEN
        in6_addr.sin6_len = sizeof(in6_addr);
#endif
        registerHostaddr((struct sockaddr *)&in6_addr, sizeof(in6_addr),
                         IN6_IS_ADDR_MULTICAST(&in6_addr.sin6_addr) ?
                         BROADCAST_QUERY : QUERY);
#endif
    }
}

static ARRAYofARRAY8 AuthenticationNames;

#if 0
static void
registerAuthenticationName(char *name, int namelen)
{
    ARRAY8Ptr authName;
    if (!XdmcpReallocARRAYofARRAY8(&AuthenticationNames,
                                   AuthenticationNames.length + 1))
        return;
    authName = &AuthenticationNames.data[AuthenticationNames.length - 1];
    if (!XdmcpAllocARRAY8(authName, namelen))
        return;
    memmove(authName->data, name, namelen);
}
#endif

static int
initXDMCP()
{
    XdmcpHeader header;
#if 0
    int i;
#endif
#ifndef STREAMSCONN
#ifdef SO_BROADCAST
    int soopts;
#endif
#endif

    header.version = XDM_PROTOCOL_VERSION;
    header.length = 1;
#if 0
    for (i = 0; i < (int)AuthenticationNames.length; i++)
        header.length += 2 + AuthenticationNames.data[i].length;
#endif

    header.opcode = (CARD16)BROADCAST_QUERY;
    XdmcpWriteHeader(&broadcastBuffer, &header);
    XdmcpWriteARRAYofARRAY8(&broadcastBuffer, &AuthenticationNames);

    header.opcode = (CARD16)QUERY;
    XdmcpWriteHeader(&directBuffer, &header);
    XdmcpWriteARRAYofARRAY8(&directBuffer, &AuthenticationNames);

#if defined(STREAMSCONN)
    if ((socketFD = t_open("/dev/udp", O_RDWR, 0)) < 0)
        return 0;

    if (t_bind(socketFD, 0, 0) < 0) {
        t_close(socketFD);
        return False;
    }

    /*
     * This part of the code looks contrived. It will actually fit in nicely
     * when the CLTS part of Xtrans is implemented.
     */
    {
        struct netconfig *nconf;

        if (!(nconf = getnetconfigent("udp"))) {
            t_unbind(socketFD);
            t_close(socketFD);
            return False;
        }

        if (netdir_options(nconf, ND_SET_BROADCAST, socketFD, 0)) {
            freenetconfigent(nconf);
            t_unbind(socketFD);
            t_close(socketFD);
            return False;
        }

        freenetconfigent(nconf);
    }
#else
    if ((socketFD = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
        return False;
#if defined(IPv6) && defined(AF_INET6)
    socket6FD = socket(AF_INET6, SOCK_DGRAM, 0);
#endif
# ifdef SO_BROADCAST
    soopts = 1;
    if (setsockopt(socketFD, SOL_SOCKET, SO_BROADCAST, (char *)&soopts,
                   sizeof(soopts)) < 0)
        perror("setsockopt");
# endif
#endif

    return True;
}

static void ATTR_NORETURN
chooseHost(int hid)
{
    HostName *h;
#if defined(IPv6) && defined(AF_INET6)
    char addr[64];
#endif

    for (h = hostNamedb; h; h = h->next)
        if ((int)(long)h == hid) {
            gSet(&mstrtalk);
            if ((td->displayType & d_location) == dLocal) {
                gSendInt(D_RemoteHost);
#if defined(IPv6) && defined(AF_INET6)
                switch (h->connectionType) {
                case FamilyInternet6:
                    inet_ntop(AF_INET6, h->hostaddr.data, addr, sizeof(addr));
                    break;
                default: /* FamilyInternet */
                    inet_ntop(AF_INET, h->hostaddr.data, addr, sizeof(addr));
                    break;
                }
                gSendStr(addr);
#else
                gSendStr(inet_ntoa(*(struct in_addr *)h->hostaddr.data));
#endif
                sessionExit(EX_REMOTE);
            } else {
                gSendInt(D_ChooseHost);
                gSendArr(td->clientAddr.length, (char *)td->clientAddr.data);
                gSendArr(td->clientPort.length, (char *)td->clientPort.data);
                gSendInt(td->connectionType);
                gSendArr(h->hostaddr.length, (char *)h->hostaddr.data);
                goto bout;
            }
            break;
        }
/*        logError("Internal error: chose unexisting host\n"); */
  bout:
    sessionExit(EX_NORMAL);
}

static void
directChooseHost(const char *name)
{
    HostAddr *hosts = 0;

    if (!makeSockAddrs(name, &hosts))
        return;
    gSendInt(G_Ch_Exit);
    gSet(&mstrtalk);
    if ((td->displayType & d_location) == dLocal) {
        gSendInt(D_RemoteHost);
        gSendStr(name);
        sessionExit(EX_REMOTE);
    } else {
        gSendInt(D_ChooseHost);
        gSendArr(td->clientAddr.length, (char *)td->clientAddr.data);
        gSendArr(td->clientPort.length, (char *)td->clientPort.data);
        gSendInt(td->connectionType);
        gSendArr(hosts->addrlen, (char *)hosts->addr);
        sessionExit(EX_NORMAL);
    }
}

#define PING_TRIES 3

int
doChoose(time_t *startTime)
{
    HostName **hp, *h;
    char *host, **hostp;
    struct timeval *to, tnow, nextPing;
    int pingTry, n, cmd;
    fd_set rfds;
    static int xdmcpInited;

    openGreeter();
    gSendInt(G_Choose);
    switch (cmd = ctrlGreeterWait(True, startTime)) {
    case G_Ready:
        break;
    default: /* error */
        return cmd;
    }

    if (!xdmcpInited) {
        if (!initXDMCP())
            sessionExit(EX_UNMANAGE_DPY);
        xdmcpInited = True;
    }
    if ((td->displayType & d_location) == dLocal) {
        /* XXX the config reader should do the lookup already */
        for (hostp = td->chooserHosts; *hostp; hostp++)
            if (!registerForPing(*hostp))
                logError("Unknown host %\"s specified for local chooser preload of display %s\n", *hostp, td->name);
    } else
        forEachChooserHost(&td->clientAddr, td->connectionType,
                           addChooserHost, 0);

    gSendInt(0); /* entering async mode signal */

  reping:
    for (h = hostNamedb; h; h = h->next)
        h->alive = False;
    pingTry = 0;
    goto pingen;

    for (;;) {
        to = 0;
        if (pingTry <= PING_TRIES) {
            gettimeofday(&tnow, 0);
            if (nextPing.tv_sec < tnow.tv_sec ||
                (nextPing.tv_sec == tnow.tv_sec &&
                 nextPing.tv_usec < tnow.tv_usec))
            {
                if (pingTry < PING_TRIES) {
                  pingen:
                    pingTry++;
                    doPingHosts();
                    gettimeofday(&tnow, 0);
                    nextPing = tnow;
                    nextPing.tv_sec++;
                } else {
                    for (hp = &hostNamedb; *hp;)
                        if (!(*hp)->alive) {
                            h = (*hp)->next;
                            disposeHostname(*hp);
                            gSendInt(G_Ch_RemoveHost);
                            gSendInt((int)(long)*hp); /* just an id */
                            *hp = h;
                        } else {
                            hp = &(*hp)->next;
                        }
                    goto noto;
                }
            }
            to = &tnow;
            tnow.tv_sec = nextPing.tv_sec - tnow.tv_sec;
            tnow.tv_usec = nextPing.tv_usec - tnow.tv_usec;
            if (tnow.tv_usec < 0) {
                tnow.tv_usec += 1000000;
                tnow.tv_sec--;
            }
        }
      noto:
        FD_ZERO(&rfds);
        FD_SET(grtproc.pipe.fd.r, &rfds);
        FD_SET(socketFD, &rfds);
#if defined(IPv6) && defined(AF_INET6)
        if (socket6FD >= 0)
            FD_SET(socket6FD, &rfds);
#endif
        n = grtproc.pipe.fd.r;
        if (socketFD > n)
            n = socketFD;
#if defined(IPv6) && defined(AF_INET6)
        if (socket6FD > n)
            n = socket6FD;
#endif
        if (select(n + 1, &rfds, 0, 0, to) > 0) {
            if (FD_ISSET(grtproc.pipe.fd.r, &rfds))
                switch (cmd = ctrlGreeterWait(False, startTime)) {
                case -1:
                    break;
                case G_Ch_Refresh:
                    goto reping;
                case G_Ch_RegisterHost:
                    host = gRecvStr();
                    if (!registerForPing(host)) {
                        gSendInt(G_Ch_BadHost);
                        gSendStr(host);
                    }
                    free(host);
                    goto reping;
                case G_Ch_DirectChoice:
                    host = gRecvStr();
                    directChooseHost(host);
                    gSendInt(G_Ch_BadHost);
                    gSendStr(host);
                    free(host);
                    break;
                case G_Ready:
                    chooseHost(gRecvInt());
                    /* NOTREACHED */
                default:
                    emptyHostnames();
                    emptyPingHosts();
                    return cmd;
                }
            if (FD_ISSET(socketFD, &rfds))
                receivePacket(socketFD);
#if defined(IPv6) && defined(AF_INET6)
            if (socket6FD >= 0 && FD_ISSET(socket6FD, &rfds))
                receivePacket(socket6FD);
#endif
        }
    }

}