[svn] Make highest connection counts a bit more consistent.

[irc/rqf/shadowircd.git] / src / s_serv.c

/*
 *  ircd-ratbox: A slightly useful ircd.
 *  s_serv.c: Server related functions.
 *
 *  Copyright (C) 1990 Jarkko Oikarinen and University of Oulu, Co Center
 *  Copyright (C) 1996-2002 Hybrid Development Team
 *  Copyright (C) 2002-2005 ircd-ratbox development team
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 *  USA
 *
 *  $Id: s_serv.c 3542 2007-08-01 20:18:12Z jilles $
 */

#include "stdinc.h"

#ifdef HAVE_LIBCRYPTO
#include <openssl/rsa.h>
#endif

#include "tools.h"
#include "s_serv.h"
#include "class.h"
#include "client.h"
#include "common.h"
#include "event.h"
#include "hash.h"
#include "irc_string.h"
#include "sprintf_irc.h"
#include "ircd.h"
#include "ircd_defs.h"
#include "numeric.h"
#include "packet.h"
#include "res.h"
#include "commio.h"
#include "s_conf.h"
#include "s_newconf.h"
#include "s_log.h"
#include "s_stats.h"
#include "s_user.h"
#include "scache.h"
#include "send.h"
#include "client.h"
#include "memory.h"
#include "channel.h"            /* chcap_usage_counts stuff... */
#include "hook.h"
#include "msg.h"
#include "reject.h"

extern char *crypt();

#ifndef INADDR_NONE
#define INADDR_NONE ((unsigned int) 0xffffffff)
#endif

#ifndef HAVE_SOCKETPAIR
static int inet_socketpair(int d, int type, int protocol, int sv[2]);
#endif

int MaxConnectionCount = 1;
int MaxClientCount = 1;
int refresh_user_links = 0;

static char buf[BUFSIZE];

static void start_io(struct Client *server);

static SlinkRplHnd slink_error;
static SlinkRplHnd slink_zipstats;
/*
 * list of recognized server capabilities.  "TS" is not on the list
 * because all servers that we talk to already do TS, and the kludged
 * extra argument to "PASS" takes care of checking that.  -orabidoo
 */
struct Capability captab[] = {
/*  name     cap     */
        { "QS",         CAP_QS },
        { "EX",         CAP_EX },
        { "CHW",        CAP_CHW},
        { "IE",         CAP_IE},
        { "KLN",        CAP_KLN},
        { "GLN",        CAP_GLN},
        { "KNOCK",      CAP_KNOCK},
        { "ZIP",        CAP_ZIP},
        { "TB",         CAP_TB},
        { "UNKLN",      CAP_UNKLN},
        { "CLUSTER",    CAP_CLUSTER},
        { "ENCAP",      CAP_ENCAP },
        { "SERVICES",   CAP_SERVICE },
        { "RSFNC",      CAP_RSFNC },
        { "SAVE",       CAP_SAVE },
        { "EUID",       CAP_EUID },
        {0, 0}
};

struct SlinkRplDef slinkrpltab[] = {
        {SLINKRPL_ERROR, slink_error, SLINKRPL_FLAG_DATA},
        {SLINKRPL_ZIPSTATS, slink_zipstats, SLINKRPL_FLAG_DATA},
        {0, 0, 0},
};

static int fork_server(struct Client *client_p);

static CNCB serv_connect_callback;

void
slink_error(unsigned int rpl, unsigned int len, unsigned char *data, struct Client *server_p)
{
        char squitreason[256];

        s_assert(rpl == SLINKRPL_ERROR);

        s_assert(len < 256);
        data[len - 1] = '\0';

        sendto_realops_snomask(SNO_GENERAL, L_ALL, "SlinkError for %s: %s", server_p->name, data);
        snprintf(squitreason, sizeof squitreason, "servlink error: %s", data);
        exit_client(server_p, server_p, &me, squitreason);
}

void
slink_zipstats(unsigned int rpl, unsigned int len, unsigned char *data, struct Client *server_p)
{
        struct ZipStats zipstats;
        u_int32_t in = 0, in_wire = 0, out = 0, out_wire = 0;
        int i = 0;

        s_assert(rpl == SLINKRPL_ZIPSTATS);
        s_assert(len == 16);
        s_assert(IsCapable(server_p, CAP_ZIP));

        /* Yes, it needs to be done this way, no we cannot let the compiler
         * work with the pointer to the structure.  This works around a GCC
         * bug on SPARC that affects all versions at the time of this writing.
         * I will feed you to the creatures living in RMS's beard if you do
         * not leave this as is, without being sure that you are not causing
         * regression for most of our installed SPARC base.
         * -jmallett, 04/27/2002
         */
        memcpy(&zipstats, &server_p->localClient->zipstats, sizeof(struct ZipStats));

        in |= (data[i++] << 24);
        in |= (data[i++] << 16);
        in |= (data[i++] << 8);
        in |= (data[i++]);

        in_wire |= (data[i++] << 24);
        in_wire |= (data[i++] << 16);
        in_wire |= (data[i++] << 8);
        in_wire |= (data[i++]);

        out |= (data[i++] << 24);
        out |= (data[i++] << 16);
        out |= (data[i++] << 8);
        out |= (data[i++]);

        out_wire |= (data[i++] << 24);
        out_wire |= (data[i++] << 16);
        out_wire |= (data[i++] << 8);
        out_wire |= (data[i++]);

        zipstats.in += in;
        zipstats.inK += zipstats.in >> 10;
        zipstats.in &= 0x03ff;

        zipstats.in_wire += in_wire;
        zipstats.inK_wire += zipstats.in_wire >> 10;
        zipstats.in_wire &= 0x03ff;

        zipstats.out += out;
        zipstats.outK += zipstats.out >> 10;
        zipstats.out &= 0x03ff;

        zipstats.out_wire += out_wire;
        zipstats.outK_wire += zipstats.out_wire >> 10;
        zipstats.out_wire &= 0x03ff;

        if(zipstats.inK > 0)
                zipstats.in_ratio =
                        (((double) (zipstats.inK - zipstats.inK_wire) /
                          (double) zipstats.inK) * 100.00);
        else
                zipstats.in_ratio = 0;

        if(zipstats.outK > 0)
                zipstats.out_ratio =
                        (((double) (zipstats.outK - zipstats.outK_wire) /
                          (double) zipstats.outK) * 100.00);
        else
                zipstats.out_ratio = 0;

        memcpy(&server_p->localClient->zipstats, &zipstats, sizeof(struct ZipStats));
}

void
collect_zipstats(void *unused)
{
        dlink_node *ptr;
        struct Client *target_p;

        DLINK_FOREACH(ptr, serv_list.head)
        {
                target_p = ptr->data;
                if(IsCapable(target_p, CAP_ZIP))
                {
                        /* only bother if we haven't already got something queued... */
                        if(!target_p->localClient->slinkq)
                        {
                                target_p->localClient->slinkq = MyMalloc(1);    /* sigh.. */
                                target_p->localClient->slinkq[0] = SLINKCMD_ZIPSTATS;
                                target_p->localClient->slinkq_ofs = 0;
                                target_p->localClient->slinkq_len = 1;
                                send_queued_slink_write(target_p->localClient->ctrlfd, target_p);
                        }
                }
        }
}

/*
 * hunt_server - Do the basic thing in delivering the message (command)
 *      across the relays to the specific server (server) for
 *      actions.
 *
 *      Note:   The command is a format string and *MUST* be
 *              of prefixed style (e.g. ":%s COMMAND %s ...").
 *              Command can have only max 8 parameters.
 *
 *      server  parv[server] is the parameter identifying the
 *              target server.
 *
 *      *WARNING*
 *              parv[server] is replaced with the pointer to the
 *              real servername from the matched client (I'm lazy
 *              now --msa).
 *
 *      returns: (see #defines)
 */
int
hunt_server(struct Client *client_p, struct Client *source_p,
            const char *command, int server, int parc, const char *parv[])
{
        struct Client *target_p;
        int wilds;
        dlink_node *ptr;
        const char *old;
        char *new;

        /*
         * Assume it's me, if no server
         */
        if(parc <= server || EmptyString(parv[server]) ||
           match(parv[server], me.name) || (strcmp(parv[server], me.id) == 0))
                return (HUNTED_ISME);
        
        new = LOCAL_COPY(parv[server]);

        /*
         * These are to pickup matches that would cause the following
         * message to go in the wrong direction while doing quick fast
         * non-matching lookups.
         */
        if(MyClient(source_p))
                target_p = find_named_client(new);
        else
                target_p = find_client(new);

        if(target_p)
                if(target_p->from == source_p->from && !MyConnect(target_p))
                        target_p = NULL;

        collapse(new);
        wilds = (strchr(new, '?') || strchr(new, '*'));

        /*
         * Again, if there are no wild cards involved in the server
         * name, use the hash lookup
         */
        if(!target_p)
        {
                if(!wilds)
                {
                        if(MyClient(source_p) || !IsDigit(parv[server][0]))
                                sendto_one_numeric(source_p, ERR_NOSUCHSERVER,
                                                   form_str(ERR_NOSUCHSERVER),
                                                   parv[server]);
                        return (HUNTED_NOSUCH);
                }
                else
                {
                        target_p = NULL;

                        DLINK_FOREACH(ptr, global_client_list.head)
                        {
                                if(match(new, ((struct Client *) (ptr->data))->name))
                                {
                                        target_p = ptr->data;
                                        break;
                                }
                        }
                }
        }

        if(target_p)
        {
                if(!IsRegistered(target_p))
                {
                        sendto_one_numeric(source_p, ERR_NOSUCHSERVER,
                                           form_str(ERR_NOSUCHSERVER),
                                           parv[server]);
                        return HUNTED_NOSUCH;
                }

                if(IsMe(target_p) || MyClient(target_p))
                        return HUNTED_ISME;

                old = parv[server];
                parv[server] = get_id(target_p, target_p);

                sendto_one(target_p, command, get_id(source_p, target_p),
                           parv[1], parv[2], parv[3], parv[4], parv[5], parv[6], parv[7], parv[8]);
                parv[server] = old;
                return (HUNTED_PASS);
        }

        if(!IsDigit(parv[server][0]))
                sendto_one_numeric(source_p, ERR_NOSUCHSERVER,
                                   form_str(ERR_NOSUCHSERVER), parv[server]);
        return (HUNTED_NOSUCH);
}

/*
 * try_connections - scan through configuration and try new connections.
 * Returns the calendar time when the next call to this
 * function should be made latest. (No harm done if this
 * is called earlier or later...)
 */
void
try_connections(void *unused)
{
        struct Client *client_p;
        struct server_conf *server_p = NULL;
        struct server_conf *tmp_p;
        struct Class *cltmp;
        dlink_node *ptr;
        int connecting = FALSE;
        int confrq = 0;
        time_t next = 0;

        DLINK_FOREACH(ptr, server_conf_list.head)
        {
                tmp_p = ptr->data;

                if(ServerConfIllegal(tmp_p) || !ServerConfAutoconn(tmp_p))
                        continue;

                cltmp = tmp_p->class;

                /*
                 * Skip this entry if the use of it is still on hold until
                 * future. Otherwise handle this entry (and set it on hold
                 * until next time). Will reset only hold times, if already
                 * made one successfull connection... [this algorithm is
                 * a bit fuzzy... -- msa >;) ]
                 */
                if(tmp_p->hold > CurrentTime)
                {
                        if(next > tmp_p->hold || next == 0)
                                next = tmp_p->hold;
                        continue;
                }

                confrq = get_con_freq(cltmp);
                tmp_p->hold = CurrentTime + confrq;

                /*
                 * Found a CONNECT config with port specified, scan clients
                 * and see if this server is already connected?
                 */
                client_p = find_server(NULL, tmp_p->name);

                if(!client_p && (CurrUsers(cltmp) < MaxUsers(cltmp)) && !connecting)
                {
                        server_p = tmp_p;

                        /* We connect only one at time... */
                        connecting = TRUE;
                }

                if((next > tmp_p->hold) || (next == 0))
                        next = tmp_p->hold;
        }

        /* TODO: change this to set active flag to 0 when added to event! --Habeeb */
        if(GlobalSetOptions.autoconn == 0)
                return;

        if(!connecting)
                return;

        /* move this connect entry to end.. */
        dlinkDelete(&server_p->node, &server_conf_list);
        dlinkAddTail(server_p, &server_p->node, &server_conf_list);

        /*
         * We used to only print this if serv_connect() actually
         * suceeded, but since comm_tcp_connect() can call the callback
         * immediately if there is an error, we were getting error messages
         * in the wrong order. SO, we just print out the activated line,
         * and let serv_connect() / serv_connect_callback() print an
         * error afterwards if it fails.
         *   -- adrian
         */
#ifndef HIDE_SERVERS_IPS
        sendto_realops_snomask(SNO_GENERAL, L_ALL,
                        "Connection to %s[%s] activated.",
                        server_p->name, server_p->host);
#else
        sendto_realops_snomask(SNO_GENERAL, L_ALL,
                        "Connection to %s activated",
                        server_p->name);
#endif

        serv_connect(server_p, 0);
}

int
check_server(const char *name, struct Client *client_p)
{
        struct server_conf *server_p = NULL;
        struct server_conf *tmp_p;
        dlink_node *ptr;
        int error = -1;

        s_assert(NULL != client_p);
        if(client_p == NULL)
                return error;

        if(!(client_p->localClient->passwd))
                return -2;

        if(strlen(name) > HOSTLEN)
                return -4;

        DLINK_FOREACH(ptr, server_conf_list.head)
        {
                tmp_p = ptr->data;

                if(ServerConfIllegal(tmp_p))
                        continue;

                if(!match(tmp_p->name, name))
                        continue;

                error = -3;

                /* XXX: Fix me for IPv6 */
                /* XXX sockhost is the IPv4 ip as a string */
                if(match(tmp_p->host, client_p->host) ||
                   match(tmp_p->host, client_p->sockhost))
                {
                        error = -2;

                        if(ServerConfEncrypted(tmp_p))
                        {
                                if(!strcmp(tmp_p->passwd, crypt(client_p->localClient->passwd,
                                                                tmp_p->passwd)))
                                {
                                        server_p = tmp_p;
                                        break;
                                }
                        }
                        else if(!strcmp(tmp_p->passwd, client_p->localClient->passwd))
                        {
                                server_p = tmp_p;
                                break;
                        }
                }
        }

        if(server_p == NULL)
                return error;

        attach_server_conf(client_p, server_p);

        /* clear ZIP/TB if they support but we dont want them */
#ifdef HAVE_LIBZ
        if(!ServerConfCompressed(server_p))
#endif
                ClearCap(client_p, CAP_ZIP);

        if(!ServerConfTb(server_p))
                ClearCap(client_p, CAP_TB);

        return 0;
}

/*
 * send_capabilities
 *
 * inputs       - Client pointer to send to
 *              - int flag of capabilities that this server has
 * output       - NONE
 * side effects - send the CAPAB line to a server  -orabidoo
 *
 */
void
send_capabilities(struct Client *client_p, int cap_can_send)
{
        struct Capability *cap;
        char msgbuf[BUFSIZE];
        char *t;
        int tl;

        t = msgbuf;

        for (cap = captab; cap->name; ++cap)
        {
                if(cap->cap & cap_can_send)
                {
                        tl = ircsprintf(t, "%s ", cap->name);
                        t += tl;
                }
        }

        t--;
        *t = '\0';

        sendto_one(client_p, "CAPAB :%s", msgbuf);
}

/* burst_modes_TS5()
 *
 * input        - client to burst to, channel name, list to burst, mode flag
 * output       -
 * side effects - client is sent a list of +b, or +e, or +I modes
 */
static void
burst_modes_TS5(struct Client *client_p, char *chname, dlink_list *list, char flag)
{
        dlink_node *ptr;
        struct Ban *banptr;
        char mbuf[MODEBUFLEN];
        char pbuf[BUFSIZE];
        int tlen;
        int mlen;
        int cur_len;
        char *mp;
        char *pp;
        int count = 0;

        mlen = ircsprintf(buf, ":%s MODE %s +", me.name, chname);
        cur_len = mlen;

        mp = mbuf;
        pp = pbuf;

        DLINK_FOREACH(ptr, list->head)
        {
                banptr = ptr->data;
                tlen = strlen(banptr->banstr) + 3;

                /* uh oh */
                if(tlen > MODEBUFLEN)
                        continue;

                if((count >= MAXMODEPARAMS) || ((cur_len + tlen + 2) > (BUFSIZE - 3)))
                {
                        sendto_one(client_p, "%s%s %s", buf, mbuf, pbuf);

                        mp = mbuf;
                        pp = pbuf;
                        cur_len = mlen;
                        count = 0;
                }

                *mp++ = flag;
                *mp = '\0';
                pp += ircsprintf(pp, "%s ", banptr->banstr);
                cur_len += tlen;
                count++;
        }

        if(count != 0)
                sendto_one(client_p, "%s%s %s", buf, mbuf, pbuf);
}

/* burst_modes_TS6()
 *
 * input        - client to burst to, channel name, list to burst, mode flag
 * output       -
 * side effects - client is sent a list of +b, +e, or +I modes
 */
static void
burst_modes_TS6(struct Client *client_p, struct Channel *chptr, 
                dlink_list *list, char flag)
{
        dlink_node *ptr;
        struct Ban *banptr;
        char *t;
        int tlen;
        int mlen;
        int cur_len;

        cur_len = mlen = ircsprintf(buf, ":%s BMASK %ld %s %c :",
                                    me.id, (long) chptr->channelts, chptr->chname, flag);
        t = buf + mlen;

        DLINK_FOREACH(ptr, list->head)
        {
                banptr = ptr->data;

                tlen = strlen(banptr->banstr) + 1;

                /* uh oh */
                if(cur_len + tlen > BUFSIZE - 3)
                {
                        /* the one we're trying to send doesnt fit at all! */
                        if(cur_len == mlen)
                        {
                                s_assert(0);
                                continue;
                        }

                        /* chop off trailing space and send.. */
                        *(t-1) = '\0';
                        sendto_one(client_p, "%s", buf);
                        cur_len = mlen;
                        t = buf + mlen;
                }

                ircsprintf(t, "%s ", banptr->banstr);
                t += tlen;
                cur_len += tlen;
        }

        /* cant ever exit the loop above without having modified buf,
         * chop off trailing space and send.
         */
        *(t-1) = '\0';
        sendto_one(client_p, "%s", buf);
}

/*
 * burst_TS5
 * 
 * inputs       - client (server) to send nick towards
 *              - client to send nick for
 * output       - NONE
 * side effects - NICK message is sent towards given client_p
 */
static void
burst_TS5(struct Client *client_p)
{
        static char ubuf[12];
        struct Client *target_p;
        struct Channel *chptr;
        struct membership *msptr;
        hook_data_client hclientinfo;
        hook_data_channel hchaninfo;
        dlink_node *ptr;
        dlink_node *uptr;
        char *t;
        int tlen, mlen;
        int cur_len = 0;

        hclientinfo.client = hchaninfo.client = client_p;

        DLINK_FOREACH(ptr, global_client_list.head)
        {
                target_p = ptr->data;

                if(!IsPerson(target_p))
                        continue;

                send_umode(NULL, target_p, 0, 0, ubuf);
                if(!*ubuf)
                {
                        ubuf[0] = '+';
                        ubuf[1] = '\0';
                }

                sendto_one(client_p, "NICK %s %d %ld %s %s %s %s :%s",
                           target_p->name, target_p->hopcount + 1,
                           (long) target_p->tsinfo, ubuf,
                           target_p->username, target_p->host,
                           target_p->user->server, target_p->info);

                if(IsDynSpoof(target_p))
                        sendto_one(client_p, ":%s ENCAP * REALHOST %s",
                                        target_p->name, target_p->orighost);
                if(!EmptyString(target_p->user->suser))
                        sendto_one(client_p, ":%s ENCAP * LOGIN %s",
                                        target_p->name, target_p->user->suser);

                if(ConfigFileEntry.burst_away && !EmptyString(target_p->user->away))
                        sendto_one(client_p, ":%s AWAY :%s",
                                   target_p->name, target_p->user->away);

                hclientinfo.target = target_p;
                call_hook(h_burst_client, &hclientinfo);
        }

        DLINK_FOREACH(ptr, global_channel_list.head)
        {
                chptr = ptr->data;

                if(*chptr->chname != '#')
                        continue;

                cur_len = mlen = ircsprintf(buf, ":%s SJOIN %ld %s %s :", me.name,
                                (long) chptr->channelts, chptr->chname, 
                                channel_modes(chptr, client_p));

                t = buf + mlen;

                DLINK_FOREACH(uptr, chptr->members.head)
                {
                        msptr = uptr->data;

                        tlen = strlen(msptr->client_p->name) + 1;
                        if(is_chanop(msptr))
                                tlen++;
                        if(is_voiced(msptr))
                                tlen++;

                        if(cur_len + tlen >= BUFSIZE - 3)
                        {
                                t--;
                                *t = '\0';
                                sendto_one(client_p, "%s", buf);
                                cur_len = mlen;
                                t = buf + mlen;
                        }

                        ircsprintf(t, "%s%s ", find_channel_status(msptr, 1), 
                                   msptr->client_p->name);

                        cur_len += tlen;
                        t += tlen;
                }

                if (dlink_list_length(&chptr->members) > 0)
                {
                        /* remove trailing space */
                        t--;
                        *t = '\0';
                }
                sendto_one(client_p, "%s", buf);

                burst_modes_TS5(client_p, chptr->chname, &chptr->banlist, 'b');

                if(IsCapable(client_p, CAP_EX))
                        burst_modes_TS5(client_p, chptr->chname, &chptr->exceptlist, 'e');

                if(IsCapable(client_p, CAP_IE))
                        burst_modes_TS5(client_p, chptr->chname, &chptr->invexlist, 'I');

                burst_modes_TS5(client_p, chptr->chname, &chptr->quietlist, 'q');

                if(IsCapable(client_p, CAP_TB) && chptr->topic != NULL)
                        sendto_one(client_p, ":%s TB %s %ld %s%s:%s",
                                   me.name, chptr->chname, (long) chptr->topic_time,
                                   ConfigChannel.burst_topicwho ? chptr->topic_info : "",
                                   ConfigChannel.burst_topicwho ? " " : "",
                                   chptr->topic);

                hchaninfo.chptr = chptr;
                call_hook(h_burst_channel, &hchaninfo);
        }

        hclientinfo.target = NULL;
        call_hook(h_burst_finished, &hclientinfo);
}

/*
 * burst_TS6
 * 
 * inputs       - client (server) to send nick towards
 *              - client to send nick for
 * output       - NONE
 * side effects - NICK message is sent towards given client_p
 */
static void
burst_TS6(struct Client *client_p)
{
        static char ubuf[12];
        struct Client *target_p;
        struct Channel *chptr;
        struct membership *msptr;
        hook_data_client hclientinfo;
        hook_data_channel hchaninfo;
        dlink_node *ptr;
        dlink_node *uptr;
        char *t;
        int tlen, mlen;
        int cur_len = 0;

        hclientinfo.client = hchaninfo.client = client_p;

        DLINK_FOREACH(ptr, global_client_list.head)
        {
                target_p = ptr->data;

                if(!IsPerson(target_p))
                        continue;

                send_umode(NULL, target_p, 0, 0, ubuf);
                if(!*ubuf)
                {
                        ubuf[0] = '+';
                        ubuf[1] = '\0';
                }

                if(has_id(target_p) && IsCapable(client_p, CAP_EUID))
                        sendto_one(client_p, ":%s EUID %s %d %ld %s %s %s %s %s %s %s :%s",
                                   target_p->servptr->id, target_p->name,
                                   target_p->hopcount + 1, 
                                   (long) target_p->tsinfo, ubuf,
                                   target_p->username, target_p->host,
                                   IsIPSpoof(target_p) ? "0" : target_p->sockhost,
                                   target_p->id,
                                   IsDynSpoof(target_p) ? target_p->orighost : "*",
                                   EmptyString(target_p->user->suser) ? "*" : target_p->user->suser,
                                   target_p->info);
                else if(has_id(target_p))
                        sendto_one(client_p, ":%s UID %s %d %ld %s %s %s %s %s :%s",
                                   target_p->servptr->id, target_p->name,
                                   target_p->hopcount + 1, 
                                   (long) target_p->tsinfo, ubuf,
                                   target_p->username, target_p->host,
                                   IsIPSpoof(target_p) ? "0" : target_p->sockhost,
                                   target_p->id, target_p->info);
                else
                        sendto_one(client_p, "NICK %s %d %ld %s %s %s %s :%s",
                                        target_p->name,
                                        target_p->hopcount + 1,
                                        (long) target_p->tsinfo,
                                        ubuf,
                                        target_p->username, target_p->host,
                                        target_p->user->server, target_p->info);

                if(!has_id(target_p) || !IsCapable(client_p, CAP_EUID))
                {
                        if(IsDynSpoof(target_p))
                                sendto_one(client_p, ":%s ENCAP * REALHOST %s",
                                                use_id(target_p), target_p->orighost);
                        if(!EmptyString(target_p->user->suser))
                                sendto_one(client_p, ":%s ENCAP * LOGIN %s",
                                                use_id(target_p), target_p->user->suser);
                }

                if(ConfigFileEntry.burst_away && !EmptyString(target_p->user->away))
                        sendto_one(client_p, ":%s AWAY :%s",
                                   use_id(target_p),
                                   target_p->user->away);

                hclientinfo.target = target_p;
                call_hook(h_burst_client, &hclientinfo);
        }

        DLINK_FOREACH(ptr, global_channel_list.head)
        {
                chptr = ptr->data;

                if(*chptr->chname != '#')
                        continue;

                cur_len = mlen = ircsprintf(buf, ":%s SJOIN %ld %s %s :", me.id,
                                (long) chptr->channelts, chptr->chname,
                                channel_modes(chptr, client_p));

                t = buf + mlen;

                DLINK_FOREACH(uptr, chptr->members.head)
                {
                        msptr = uptr->data;

                        tlen = strlen(use_id(msptr->client_p)) + 1;
                        if(is_chanop(msptr))
                                tlen++;
                        if(is_voiced(msptr))
                                tlen++;

                        if(cur_len + tlen >= BUFSIZE - 3)
                        {
                                *(t-1) = '\0';
                                sendto_one(client_p, "%s", buf);
                                cur_len = mlen;
                                t = buf + mlen;
                        }

                        ircsprintf(t, "%s%s ", find_channel_status(msptr, 1), 
                                   use_id(msptr->client_p));

                        cur_len += tlen;
                        t += tlen;
                }

                if (dlink_list_length(&chptr->members) > 0)
                {
                        /* remove trailing space */
                        *(t-1) = '\0';
                }
                sendto_one(client_p, "%s", buf);

                if(dlink_list_length(&chptr->banlist) > 0)
                        burst_modes_TS6(client_p, chptr, &chptr->banlist, 'b');

                if(IsCapable(client_p, CAP_EX) &&
                   dlink_list_length(&chptr->exceptlist) > 0)
                        burst_modes_TS6(client_p, chptr, &chptr->exceptlist, 'e');

                if(IsCapable(client_p, CAP_IE) &&
                   dlink_list_length(&chptr->invexlist) > 0)
                        burst_modes_TS6(client_p, chptr, &chptr->invexlist, 'I');

                if(dlink_list_length(&chptr->quietlist) > 0)
                        burst_modes_TS6(client_p, chptr, &chptr->quietlist, 'q');

                if(IsCapable(client_p, CAP_TB) && chptr->topic != NULL)
                        sendto_one(client_p, ":%s TB %s %ld %s%s:%s",
                                   me.id, chptr->chname, (long) chptr->topic_time,
                                   ConfigChannel.burst_topicwho ? chptr->topic_info : "",
                                   ConfigChannel.burst_topicwho ? " " : "",
                                   chptr->topic);

                hchaninfo.chptr = chptr;
                call_hook(h_burst_channel, &hchaninfo);
        }

        hclientinfo.target = NULL;
        call_hook(h_burst_finished, &hclientinfo);
}

/*
 * show_capabilities - show current server capabilities
 *
 * inputs       - pointer to an struct Client
 * output       - pointer to static string
 * side effects - build up string representing capabilities of server listed
 */
const char *
show_capabilities(struct Client *target_p)
{
        static char msgbuf[BUFSIZE];
        struct Capability *cap;
        char *t;
        int tl;

        t = msgbuf;
        tl = ircsprintf(msgbuf, "TS ");
        t += tl;

        if(!IsServer(target_p) || !target_p->serv->caps)        /* short circuit if no caps */
        {
                msgbuf[2] = '\0';
                return msgbuf;
        }

        for (cap = captab; cap->cap; ++cap)
        {
                if(cap->cap & target_p->serv->caps)
                {
                        tl = ircsprintf(t, "%s ", cap->name);
                        t += tl;
                }
        }

        t--;
        *t = '\0';

        return msgbuf;
}

/*
 * server_estab
 *
 * inputs       - pointer to a struct Client
 * output       -
 * side effects -
 */
int
server_estab(struct Client *client_p)
{
        struct Client *target_p;
        struct server_conf *server_p;
        hook_data_client hdata;
        char *host;
        dlink_node *ptr;

        s_assert(NULL != client_p);
        if(client_p == NULL)
                return -1;
        ClearAccess(client_p);

        host = client_p->name;

        if((server_p = client_p->localClient->att_sconf) == NULL)
        {
                /* This shouldn't happen, better tell the ops... -A1kmm */
                sendto_realops_snomask(SNO_GENERAL, is_remote_connect(client_p) ? L_NETWIDE : L_ALL,
                                     "Warning: Lost connect{} block for server %s!", host);
                return exit_client(client_p, client_p, client_p, "Lost connect{} block!");
        }

        /* We shouldn't have to check this, it should already done before
         * server_estab is called. -A1kmm
         */
        if(client_p->localClient->passwd)
        {
                memset(client_p->localClient->passwd, 0, strlen(client_p->localClient->passwd));
                MyFree(client_p->localClient->passwd);
                client_p->localClient->passwd = NULL;
        }

        /* Its got identd , since its a server */
        SetGotId(client_p);

        /* If there is something in the serv_list, it might be this
         * connecting server..
         */
        if(!ServerInfo.hub && serv_list.head)
        {
                if(client_p != serv_list.head->data || serv_list.head->next)
                {
                        ServerStats->is_ref++;
                        sendto_one(client_p, "ERROR :I'm a leaf not a hub");
                        return exit_client(client_p, client_p, client_p, "I'm a leaf");
                }
        }

        if(IsUnknown(client_p))
        {
                /*
                 * jdc -- 1.  Use EmptyString(), not [0] index reference.
                 *        2.  Check ->spasswd, not ->passwd.
                 */
                if(!EmptyString(server_p->spasswd))
                {
                        /* kludge, if we're not using TS6, dont ever send
                         * ourselves as being TS6 capable.
                         */
                        if(ServerInfo.use_ts6)
                                sendto_one(client_p, "PASS %s TS %d :%s", 
                                           server_p->spasswd, TS_CURRENT, me.id);
                        else
                                sendto_one(client_p, "PASS %s :TS",
                                           server_p->spasswd);
                }

                /* pass info to new server */
                send_capabilities(client_p, default_server_capabs
                                  | (ServerConfCompressed(server_p) ? CAP_ZIP_SUPPORTED : 0)
                                  | (ServerConfTb(server_p) ? CAP_TB : 0));

                sendto_one(client_p, "SERVER %s 1 :%s%s",
                           me.name,
                           ConfigServerHide.hidden ? "(H) " : "",
                           (me.info[0]) ? (me.info) : "IRCers United");
        }

        if(!comm_set_buffers(client_p->localClient->fd, READBUF_SIZE))
                report_error(SETBUF_ERROR_MSG, 
                             get_server_name(client_p, SHOW_IP), 
                             log_client_name(client_p, SHOW_IP), errno);

        /* Hand the server off to servlink now */
        if(IsCapable(client_p, CAP_ZIP))
        {
                if(fork_server(client_p) < 0)
                {
                        sendto_realops_snomask(SNO_GENERAL, is_remote_connect(client_p) ? L_NETWIDE : L_ALL,
                                             "Warning: fork failed for server %s -- check servlink_path (%s)",
                                             get_server_name(client_p, HIDE_IP),
                                             ConfigFileEntry.servlink_path);
                        return exit_client(client_p, client_p, client_p, "Fork failed");
                }
                start_io(client_p);
                SetServlink(client_p);
        }

        sendto_one(client_p, "SVINFO %d %d 0 :%ld", TS_CURRENT, TS_MIN, CurrentTime);

        client_p->servptr = &me;

        if(IsAnyDead(client_p))
                return CLIENT_EXITED;

        SetServer(client_p);

        /* Update the capability combination usage counts */
        set_chcap_usage_counts(client_p);

        dlinkAdd(client_p, &client_p->lnode, &me.serv->servers);
        del_unknown_ip(client_p);
        dlinkMoveNode(&client_p->localClient->tnode, &unknown_list, &serv_list);
        dlinkAddTailAlloc(client_p, &global_serv_list);

        if(has_id(client_p))
                add_to_id_hash(client_p->id, client_p);

        add_to_client_hash(client_p->name, client_p);
        /* doesnt duplicate client_p->serv if allocated this struct already */
        make_server(client_p);
        client_p->serv->up = me.name;
        client_p->serv->upid = me.id;

        client_p->serv->caps = client_p->localClient->caps;

        if(client_p->localClient->fullcaps)
        {
                DupString(client_p->serv->fullcaps, client_p->localClient->fullcaps);
                MyFree(client_p->localClient->fullcaps);
                client_p->localClient->fullcaps = NULL;
        }

        /* add it to scache */
        find_or_add(client_p->name);
        client_p->localClient->firsttime = CurrentTime;
        /* fixing eob timings.. -gnp */

        if((dlink_list_length(&lclient_list) + dlink_list_length(&serv_list)) >
           (unsigned long)MaxConnectionCount)
                MaxConnectionCount = dlink_list_length(&lclient_list) + 
                                        dlink_list_length(&serv_list);

        /* Show the real host/IP to admins */
        sendto_realops_snomask(SNO_GENERAL, L_ALL,
                        "Link with %s established: (%s) link",
                        get_server_name(client_p, SHOW_IP),
                        show_capabilities(client_p));

        ilog(L_SERVER, "Link with %s established: (%s) link",
             log_client_name(client_p, SHOW_IP), show_capabilities(client_p));

        hdata.client = &me;
        hdata.target = client_p;
        call_hook(h_server_introduced, &hdata);

        if(HasServlink(client_p))
        {
                /* we won't overflow FD_DESC_SZ here, as it can hold
                 * client_p->name + 64
                 */
                comm_note(client_p->localClient->fd, "slink data: %s", client_p->name);
                comm_note(client_p->localClient->ctrlfd, "slink ctrl: %s", client_p->name);
        }
        else
                comm_note(client_p->localClient->fd, "Server: %s", client_p->name);

        /*
         ** Old sendto_serv_but_one() call removed because we now
         ** need to send different names to different servers
         ** (domain name matching) Send new server to other servers.
         */
        DLINK_FOREACH(ptr, serv_list.head)
        {
                target_p = ptr->data;

                if(target_p == client_p)
                        continue;

                if(has_id(target_p) && has_id(client_p))
                {
                        sendto_one(target_p, ":%s SID %s 2 %s :%s%s",
                                   me.id, client_p->name, client_p->id,
                                   IsHidden(client_p) ? "(H) " : "", client_p->info);

                        if(IsCapable(target_p, CAP_ENCAP) &&
                           !EmptyString(client_p->serv->fullcaps))
                                sendto_one(target_p, ":%s ENCAP * GCAP :%s",
                                        client_p->id, client_p->serv->fullcaps);
                }
                else
                {
                        sendto_one(target_p, ":%s SERVER %s 2 :%s%s",
                                   me.name, client_p->name,
                                   IsHidden(client_p) ? "(H) " : "", client_p->info);

                        if(IsCapable(target_p, CAP_ENCAP) &&
                           !EmptyString(client_p->serv->fullcaps))
                                sendto_one(target_p, ":%s ENCAP * GCAP :%s",
                                        client_p->name, client_p->serv->fullcaps);
                }
        }

        /*
         ** Pass on my client information to the new server
         **
         ** First, pass only servers (idea is that if the link gets
         ** cancelled beacause the server was already there,
         ** there are no NICK's to be cancelled...). Of course,
         ** if cancellation occurs, all this info is sent anyway,
         ** and I guess the link dies when a read is attempted...? --msa
         ** 
         ** Note: Link cancellation to occur at this point means
         ** that at least two servers from my fragment are building
         ** up connection this other fragment at the same time, it's
         ** a race condition, not the normal way of operation...
         **
         ** ALSO NOTE: using the get_client_name for server names--
         **    see previous *WARNING*!!! (Also, original inpath
         **    is destroyed...)
         */
        DLINK_FOREACH(ptr, global_serv_list.head)
        {
                target_p = ptr->data;

                /* target_p->from == target_p for target_p == client_p */
                if(IsMe(target_p) || target_p->from == client_p)
                        continue;

                /* presumption, if target has an id, so does its uplink */
                if(has_id(client_p) && has_id(target_p))
                        sendto_one(client_p, ":%s SID %s %d %s :%s%s",
                                   target_p->serv->upid, target_p->name,
                                   target_p->hopcount + 1, target_p->id,
                                   IsHidden(target_p) ? "(H) " : "", target_p->info);
                else
                        sendto_one(client_p, ":%s SERVER %s %d :%s%s",
                                   target_p->serv->up,
                                   target_p->name, target_p->hopcount + 1,
                                   IsHidden(target_p) ? "(H) " : "", target_p->info);

                if(IsCapable(client_p, CAP_ENCAP) && 
                   !EmptyString(target_p->serv->fullcaps))
                        sendto_one(client_p, ":%s ENCAP * GCAP :%s",
                                        get_id(target_p, client_p),
                                        target_p->serv->fullcaps);
        }

        if(has_id(client_p))
                burst_TS6(client_p);
        else
                burst_TS5(client_p);

        /* Always send a PING after connect burst is done */
        sendto_one(client_p, "PING :%s", get_id(&me, client_p));

        free_pre_client(client_p);

        return 0;
}

static void
start_io(struct Client *server)
{
        unsigned char *iobuf;
        int c = 0;
        int linecount = 0;
        int linelen;

        iobuf = MyMalloc(256);  /* XXX: This seems arbitrary. Perhaps make it IRCD_BUFSIZE? --nenolod */

        if(IsCapable(server, CAP_ZIP))
        {
                /* ziplink */
                iobuf[c++] = SLINKCMD_SET_ZIP_OUT_LEVEL;
                iobuf[c++] = 0; /* |          */
                iobuf[c++] = 1; /* \ len is 1 */
                iobuf[c++] = ConfigFileEntry.compression_level;
                iobuf[c++] = SLINKCMD_START_ZIP_IN;
                iobuf[c++] = SLINKCMD_START_ZIP_OUT;
        }

        while (MyConnect(server))
        {
                linecount++;

                iobuf = MyRealloc(iobuf, (c + READBUF_SIZE + 64));

                /* store data in c+3 to allow for SLINKCMD_INJECT_RECVQ and len u16 */
                linelen = linebuf_get(&server->localClient->buf_recvq, (char *) (iobuf + c + 3), READBUF_SIZE, LINEBUF_PARTIAL, LINEBUF_RAW);   /* include partial lines */

                if(linelen)
                {
                        iobuf[c++] = SLINKCMD_INJECT_RECVQ;
                        iobuf[c++] = (linelen >> 8);
                        iobuf[c++] = (linelen & 0xff);
                        c += linelen;
                }
                else
                        break;
        }

        while (MyConnect(server))
        {
                linecount++;

                iobuf = MyRealloc(iobuf, (c + BUF_DATA_SIZE + 64));

                /* store data in c+3 to allow for SLINKCMD_INJECT_RECVQ and len u16 */
                linelen = linebuf_get(&server->localClient->buf_sendq, 
                                      (char *) (iobuf + c + 3), READBUF_SIZE, 
                                      LINEBUF_PARTIAL, LINEBUF_PARSED); /* include partial lines */

                if(linelen)
                {
                        iobuf[c++] = SLINKCMD_INJECT_SENDQ;
                        iobuf[c++] = (linelen >> 8);
                        iobuf[c++] = (linelen & 0xff);
                        c += linelen;
                }
                else
                        break;
        }

        /* start io */
        iobuf[c++] = SLINKCMD_INIT;

        server->localClient->slinkq = iobuf;
        server->localClient->slinkq_ofs = 0;
        server->localClient->slinkq_len = c;

        /* schedule a write */
        send_queued_slink_write(server->localClient->ctrlfd, server);
}

/*
 * fork_server
 *
 * inputs       - struct Client *server
 * output       - success: 0 / failure: -1
 * side effect  - fork, and exec SERVLINK to handle this connection
 */
static int
fork_server(struct Client *server)
{
        int ret;
        int i;
        int ctrl_fds[2];
        int data_fds[2];

        char fd_str[4][6];
        char *kid_argv[7];
        char slink[] = "-slink";


        /* ctrl */
#ifdef HAVE_SOCKETPAIR
        if(socketpair(AF_UNIX, SOCK_STREAM, 0, ctrl_fds) < 0)
#else
        if(inet_socketpair(AF_INET,SOCK_STREAM, 0, ctrl_fds) < 0)
#endif
                goto fork_error;

        

        /* data */
#ifdef HAVE_SOCKETPAIR
        if(socketpair(AF_UNIX, SOCK_STREAM, 0, data_fds) < 0)
#else
        if(inet_socketpair(AF_INET,SOCK_STREAM, 0, data_fds) < 0)
#endif
                goto fork_error;


#ifdef __CYGWIN__
        if((ret = vfork()) < 0)
#else
        if((ret = fork()) < 0)
#endif
                goto fork_error;
        else if(ret == 0)
        {
                int maxconn = comm_get_maxconnections();

                /* set our fds as non blocking and close everything else */
                for (i = 0; i < maxconn; i++)
                {
                                

                        if((i == ctrl_fds[1]) || (i == data_fds[1]) || (i == server->localClient->fd)) 
                        {
                                comm_set_nb(i);
                        }
                        else
                        {
#ifdef __CYGWIN__
                                if(i > 2)       /* don't close std* */
#endif
                                        close(i);
                        }
                }

                ircsnprintf(fd_str[0], sizeof(fd_str[0]), "%d", ctrl_fds[1]);
                ircsnprintf(fd_str[1], sizeof(fd_str[1]), "%d", data_fds[1]);
                ircsnprintf(fd_str[2], sizeof(fd_str[2]), "%d", server->localClient->fd);
                kid_argv[0] = slink;
                kid_argv[1] = fd_str[0];
                kid_argv[2] = fd_str[1];
                kid_argv[3] = fd_str[2];
                kid_argv[4] = NULL;

                /* exec servlink program */
                execv(ConfigFileEntry.servlink_path, kid_argv);

                /* We're still here, abort. */
                _exit(1);
        }
        else
        {
                comm_close(server->localClient->fd);

                /* close the childs end of the pipes */
                close(ctrl_fds[1]);
                close(data_fds[1]);
                
                s_assert(server->localClient);
                server->localClient->ctrlfd = ctrl_fds[0];
                server->localClient->fd = data_fds[0];

                if(!comm_set_nb(server->localClient->fd))
                {
                        report_error(NONB_ERROR_MSG,
                                        get_server_name(server, SHOW_IP),
                                        log_client_name(server, SHOW_IP),
                                        errno);
                }

                if(!comm_set_nb(server->localClient->ctrlfd))
                {
                        report_error(NONB_ERROR_MSG,
                                        get_server_name(server, SHOW_IP),
                                        log_client_name(server, SHOW_IP),
                                        errno);
                }

                comm_open(server->localClient->ctrlfd, FD_SOCKET, NULL);
                comm_open(server->localClient->fd, FD_SOCKET, NULL);

                read_ctrl_packet(server->localClient->ctrlfd, server);
                read_packet(server->localClient->fd, server);
        }

        return 0;

      fork_error:
        /* this is ugly, but nicer than repeating
         * about 50 close() statements everywhre... */
        close(data_fds[0]);
        close(data_fds[1]);
        close(ctrl_fds[0]);
        close(ctrl_fds[1]);
        return -1;
}

/*
 * New server connection code
 * Based upon the stuff floating about in s_bsd.c
 *   -- adrian
 */

/*
 * serv_connect() - initiate a server connection
 *
 * inputs       - pointer to conf 
 *              - pointer to client doing the connet
 * output       -
 * side effects -
 *
 * This code initiates a connection to a server. It first checks to make
 * sure the given server exists. If this is the case, it creates a socket,
 * creates a client, saves the socket information in the client, and
 * initiates a connection to the server through comm_connect_tcp(). The
 * completion of this goes through serv_completed_connection().
 *
 * We return 1 if the connection is attempted, since we don't know whether
 * it suceeded or not, and 0 if it fails in here somewhere.
 */
int
serv_connect(struct server_conf *server_p, struct Client *by)
{
        struct Client *client_p;
        struct irc_sockaddr_storage myipnum; 
        int fd;

        s_assert(server_p != NULL);
        if(server_p == NULL)
                return 0;

        /*
         * Make sure this server isn't already connected
         */
        if((client_p = find_server(NULL, server_p->name)))
        {
                sendto_realops_snomask(SNO_GENERAL, L_ALL,
                                     "Server %s already present from %s",
                                     server_p->name, get_server_name(client_p, SHOW_IP));
                if(by && IsPerson(by) && !MyClient(by))
                        sendto_one_notice(by, ":Server %s already present from %s",
                                          server_p->name, get_server_name(client_p, SHOW_IP));
                return 0;
        }

        /* create a socket for the server connection */
        if((fd = comm_socket(server_p->aftype, SOCK_STREAM, 0, NULL)) < 0)
        {
                /* Eek, failure to create the socket */
                report_error("opening stream socket to %s: %s", 
                             server_p->name, server_p->name, errno);
                return 0;
        }

        /* servernames are always guaranteed under HOSTLEN chars */
        comm_note(fd, "Server: %s", server_p->name);

        /* Create a local client */
        client_p = make_client(NULL);

        /* Copy in the server, hostname, fd
         * The sockhost may be a hostname, this will be corrected later
         * -- jilles
         */
        strlcpy(client_p->name, server_p->name, sizeof(client_p->name));
        strlcpy(client_p->host, server_p->host, sizeof(client_p->host));
        strlcpy(client_p->sockhost, server_p->host, sizeof(client_p->sockhost));
        client_p->localClient->fd = fd;

        /*
         * Set up the initial server evilness, ripped straight from
         * connect_server(), so don't blame me for it being evil.
         *   -- adrian
         */

        if(!comm_set_buffers(client_p->localClient->fd, READBUF_SIZE))
        {
                report_error(SETBUF_ERROR_MSG,
                                get_server_name(client_p, SHOW_IP),
                                log_client_name(client_p, SHOW_IP),
                                errno);
        }

        /*
         * Attach config entries to client here rather than in
         * serv_connect_callback(). This to avoid null pointer references.
         */
        attach_server_conf(client_p, server_p);

        /*
         * at this point we have a connection in progress and C/N lines
         * attached to the client, the socket info should be saved in the
         * client and it should either be resolved or have a valid address.
         *
         * The socket has been connected or connect is in progress.
         */
        make_server(client_p);
        if(by && IsPerson(by))
        {
                strcpy(client_p->serv->by, by->name);
                if(client_p->serv->user)
                        free_user(client_p->serv->user, NULL);
                client_p->serv->user = by->user;
                by->user->refcnt++;
        }
        else
        {
                strcpy(client_p->serv->by, "AutoConn.");
                if(client_p->serv->user)
                        free_user(client_p->serv->user, NULL);
                client_p->serv->user = NULL;
        }
        client_p->serv->up = me.name;
        client_p->serv->upid = me.id;
        SetConnecting(client_p);
        dlinkAddTail(client_p, &client_p->node, &global_client_list);

        /* log */
        ilog(L_SERVER, "Connecting to %s[%s] port %d (%s)", server_p->name, server_p->host, server_p->port,
#ifdef IPV6
                        server_p->aftype == AF_INET6 ? "IPv6" :
#endif
                        (server_p->aftype == AF_INET ? "IPv4" : "?"));

        if(ServerConfVhosted(server_p))
        {
                memcpy(&myipnum, &server_p->my_ipnum, sizeof(myipnum));
                ((struct sockaddr_in *)&myipnum)->sin_port = 0;
                myipnum.ss_family = server_p->aftype;
                                
        }
        else if(server_p->aftype == AF_INET && ServerInfo.specific_ipv4_vhost)
        {
                memcpy(&myipnum, &ServerInfo.ip, sizeof(myipnum));
                ((struct sockaddr_in *)&myipnum)->sin_port = 0;
                myipnum.ss_family = AF_INET;
                SET_SS_LEN(myipnum, sizeof(struct sockaddr_in));
        }
        
#ifdef IPV6
        else if((server_p->aftype == AF_INET6) && ServerInfo.specific_ipv6_vhost)
        {
                memcpy(&myipnum, &ServerInfo.ip6, sizeof(myipnum));
                ((struct sockaddr_in6 *)&myipnum)->sin6_port = 0;
                myipnum.ss_family = AF_INET6;
                SET_SS_LEN(myipnum, sizeof(struct sockaddr_in6));
        }
#endif
        else
        {
                comm_connect_tcp(client_p->localClient->fd, server_p->host,
                                 server_p->port, NULL, 0, serv_connect_callback, 
                                 client_p, server_p->aftype, 
                                 ConfigFileEntry.connect_timeout);
                 return 1;
        }

        comm_connect_tcp(client_p->localClient->fd, server_p->host,
                         server_p->port, (struct sockaddr *) &myipnum,
                         GET_SS_LEN(myipnum), serv_connect_callback, client_p,
                         myipnum.ss_family, ConfigFileEntry.connect_timeout);

        return 1;
}

/*
 * serv_connect_callback() - complete a server connection.
 * 
 * This routine is called after the server connection attempt has
 * completed. If unsucessful, an error is sent to ops and the client
 * is closed. If sucessful, it goes through the initialisation/check
 * procedures, the capabilities are sent, and the socket is then
 * marked for reading.
 */
static void
serv_connect_callback(int fd, int status, void *data)
{
        struct Client *client_p = data;
        struct server_conf *server_p;
        char *errstr;
        fde_t *F = comm_locate_fd(fd);

        /* First, make sure its a real client! */
        s_assert(client_p != NULL);
        s_assert(client_p->localClient->fd == fd);

        if(client_p == NULL)
                return;

        /* while we were waiting for the callback, its possible this already
         * linked in.. --fl
         */
        if(find_server(NULL, client_p->name) != NULL)
        {
                exit_client(client_p, client_p, &me, "Server Exists");
                return;
        }

        /* Next, for backward purposes, record the ip of the server */
        memcpy(&client_p->localClient->ip, &F->connect.hostaddr, sizeof client_p->localClient->ip);
        /* Set sockhost properly now -- jilles */
        inetntop_sock((struct sockaddr *)&F->connect.hostaddr,
                        client_p->sockhost, sizeof client_p->sockhost);
        
        /* Check the status */
        if(status != COMM_OK)
        {
                /* COMM_ERR_TIMEOUT wont have an errno associated with it,
                 * the others will.. --fl
                 */
                if(status == COMM_ERR_TIMEOUT)
                {
                        sendto_realops_snomask(SNO_GENERAL, is_remote_connect(client_p) ? L_NETWIDE : L_ALL,
                                        "Error connecting to %s[%s]: %s",
                                        client_p->name, 
#ifdef HIDE_SERVERS_IPS
                                        "255.255.255.255",
#else
                                        client_p->host,
#endif
                                        comm_errstr(status));
                        ilog(L_SERVER, "Error connecting to %s[%s]: %s",
                                client_p->name, client_p->sockhost,
                                comm_errstr(status));
                }
                else
                {
                        errstr = strerror(comm_get_sockerr(fd));
                        sendto_realops_snomask(SNO_GENERAL, is_remote_connect(client_p) ? L_NETWIDE : L_ALL,
                                        "Error connecting to %s[%s]: %s (%s)",
                                        client_p->name,
#ifdef HIDE_SERVERS_IPS
                                        "255.255.255.255",
#else
                                        client_p->host,
#endif
                                        comm_errstr(status), errstr);
                        ilog(L_SERVER, "Error connecting to %s[%s]: %s (%s)",
                                client_p->name, client_p->sockhost,
                                comm_errstr(status), errstr);
                }

                exit_client(client_p, client_p, &me, comm_errstr(status));
                return;
        }

        /* COMM_OK, so continue the connection procedure */
        /* Get the C/N lines */
        if((server_p = client_p->localClient->att_sconf) == NULL)
        {
                sendto_realops_snomask(SNO_GENERAL, is_remote_connect(client_p) ? L_NETWIDE : L_ALL, "Lost connect{} block for %s",
                                get_server_name(client_p, HIDE_IP));
                exit_client(client_p, client_p, &me, "Lost connect{} block");
                return;
        }

        /* Next, send the initial handshake */
        SetHandshake(client_p);

        /* kludge, if we're not using TS6, dont ever send
         * ourselves as being TS6 capable.
         */
        if(!EmptyString(server_p->spasswd))
        {
                if(ServerInfo.use_ts6)
                        sendto_one(client_p, "PASS %s TS %d :%s", 
                                   server_p->spasswd, TS_CURRENT, me.id);
                else
                        sendto_one(client_p, "PASS %s :TS",
                                   server_p->spasswd);
        }

        /* pass my info to the new server */
        send_capabilities(client_p, default_server_capabs
                          | (ServerConfCompressed(server_p) ? CAP_ZIP_SUPPORTED : 0)
                          | (ServerConfTb(server_p) ? CAP_TB : 0));

        sendto_one(client_p, "SERVER %s 1 :%s%s",
                   me.name,
                   ConfigServerHide.hidden ? "(H) " : "", me.info);

        /* 
         * If we've been marked dead because a send failed, just exit
         * here now and save everyone the trouble of us ever existing.
         */
        if(IsAnyDead(client_p))
        {
                sendto_realops_snomask(SNO_GENERAL, is_remote_connect(client_p) ? L_NETWIDE : L_ALL,
                                     "%s went dead during handshake", client_p->name);
                exit_client(client_p, client_p, &me, "Went dead during handshake");
                return;
        }

        /* don't move to serv_list yet -- we haven't sent a burst! */

        /* If we get here, we're ok, so lets start reading some data */
        read_packet(fd, client_p);
}

#ifndef HAVE_SOCKETPAIR
static int
inet_socketpair(int d, int type, int protocol, int sv[2])
{
        struct sockaddr_in addr1, addr2, addr3;
        int addr3_len = sizeof(addr3);
        int fd, rc;
        int port_no = 20000;
        
        if(d != AF_INET || type != SOCK_STREAM || protocol)
        {
                errno = EAFNOSUPPORT;
                return -1;
        }
        if(((sv[0] = socket(AF_INET, SOCK_STREAM, 0)) < 0) || ((sv[1] = socket(AF_INET, SOCK_STREAM, 0)) < 0))
                return -1;
        
        addr1.sin_port = htons(port_no);
        addr1.sin_family = AF_INET;
        addr1.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
        while ((rc = bind (sv[0], (struct sockaddr *) &addr1, sizeof (addr1))) < 0 && errno == EADDRINUSE)
                addr1.sin_port = htons(++port_no);
        
        if(rc < 0)
                return -1;
        
        if(listen(sv[0], 1) < 0)
        {
                close(sv[0]);
                close(sv[1]);
                return -1;
        }
        
        addr2.sin_port = htons(port_no);
        addr2.sin_family = AF_INET;
        addr2.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
        if(connect (sv[1], (struct sockaddr *) &addr2, sizeof (addr2)) < 0) 
        {
                close(sv[0]);
                close(sv[1]);
                return -1;
        }
        
        if((fd = accept(sv[1], (struct sockaddr *) &addr3, &addr3_len)) < 0)
        {
                close(sv[0]);
                close(sv[1]);
                return -1;
        }
        close(sv[0]);
        sv[0] = fd;
        
        return(0);

}
#endif