elemental-ircd/modules/core/m_server.c

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/*
* ircd-ratbox: A slightly useful ircd.
* m_server.c: Introduces a server.
*
* 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: m_server.c 2733 2006-11-10 00:04:08Z jilles $
*/
#include "stdinc.h"
#include "tools.h"
#include "client.h" /* client struct */
#include "common.h" /* TRUE bleah */
#include "event.h"
#include "hash.h" /* add_to_client_hash */
#include "irc_string.h"
#include "ircd.h" /* me */
#include "numeric.h" /* ERR_xxx */
#include "s_conf.h" /* struct ConfItem */
#include "s_newconf.h"
#include "s_log.h" /* log level defines */
#include "s_serv.h" /* server_estab, check_server */
#include "s_stats.h" /* ServerStats */
#include "scache.h" /* find_or_add */
#include "send.h" /* sendto_one */
#include "msg.h"
#include "parse.h"
#include "modules.h"
static int mr_server(struct Client *, struct Client *, int, const char **);
static int ms_server(struct Client *, struct Client *, int, const char **);
static int ms_sid(struct Client *, struct Client *, int, const char **);
struct Message server_msgtab = {
"SERVER", 0, 0, 0, MFLG_SLOW | MFLG_UNREG,
{{mr_server, 4}, mg_reg, mg_ignore, {ms_server, 4}, mg_ignore, mg_reg}
};
struct Message sid_msgtab = {
"SID", 0, 0, 0, MFLG_SLOW,
{mg_ignore, mg_reg, mg_ignore, {ms_sid, 5}, mg_ignore, mg_reg}
};
mapi_clist_av1 server_clist[] = { &server_msgtab, &sid_msgtab, NULL };
DECLARE_MODULE_AV1(server, NULL, NULL, server_clist, NULL, NULL, "$Revision: 2733 $");
int bogus_host(const char *host);
struct Client *server_exists(const char *);
static int set_server_gecos(struct Client *, const char *);
/*
* mr_server - SERVER message handler
* parv[0] = sender prefix
* parv[1] = servername
* parv[2] = serverinfo/hopcount
* parv[3] = serverinfo
*/
static int
mr_server(struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
{
char info[REALLEN + 1];
const char *name;
struct Client *target_p;
int hop;
name = parv[1];
hop = atoi(parv[2]);
strlcpy(info, parv[3], sizeof(info));
/*
* Reject a direct nonTS server connection if we're TS_ONLY -orabidoo
*/
if(!DoesTS(client_p))
{
sendto_realops_snomask(SNO_GENERAL, L_ALL, "Link %s dropped, non-TS server",
get_server_name(client_p, HIDE_IP));
exit_client(client_p, client_p, client_p, "Non-TS server");
return 0;
}
if(bogus_host(name))
{
exit_client(client_p, client_p, client_p, "Bogus server name");
return 0;
}
/* Now we just have to call check_server and everything should be
* check for us... -A1kmm. */
switch (check_server(name, client_p))
{
case -1:
if(ConfigFileEntry.warn_no_nline)
{
sendto_realops_snomask(SNO_GENERAL, L_ALL,
"Unauthorised server connection attempt from %s: "
"No entry for servername %s",
get_server_name(client_p, HIDE_IP), name);
ilog(L_SERVER, "Access denied, no connect block for server %s%s",
EmptyString(client_p->name) ? name : "",
log_client_name(client_p, SHOW_IP));
}
exit_client(client_p, client_p, client_p, "Invalid servername.");
return 0;
/* NOT REACHED */
break;
case -2:
sendto_realops_snomask(SNO_GENERAL, L_ALL,
"Unauthorised server connection attempt from %s: "
"Bad password for server %s",
get_server_name(client_p, HIDE_IP), name);
ilog(L_SERVER, "Access denied, invalid password for server %s%s",
EmptyString(client_p->name) ? name : "",
log_client_name(client_p, SHOW_IP));
exit_client(client_p, client_p, client_p, "Invalid password.");
return 0;
/* NOT REACHED */
break;
case -3:
sendto_realops_snomask(SNO_GENERAL, L_ALL,
"Unauthorised server connection attempt from %s: "
"Invalid host for server %s",
get_server_name(client_p, HIDE_IP), name);
ilog(L_SERVER, "Access denied, invalid host for server %s%s",
EmptyString(client_p->name) ? name : "",
log_client_name(client_p, SHOW_IP));
exit_client(client_p, client_p, client_p, "Invalid host.");
return 0;
/* NOT REACHED */
break;
/* servername is > HOSTLEN */
case -4:
sendto_realops_snomask(SNO_GENERAL, L_ALL,
"Invalid servername %s from %s",
name, get_server_name(client_p, HIDE_IP));
ilog(L_SERVER, "Access denied, invalid servername from %s",
log_client_name(client_p, SHOW_IP));
exit_client(client_p, client_p, client_p, "Invalid servername.");
return 0;
/* NOT REACHED */
break;
}
if((target_p = server_exists(name)))
{
/*
* This link is trying feed me a server that I already have
* access through another path -- multiple paths not accepted
* currently, kill this link immediately!!
*
* Rather than KILL the link which introduced it, KILL the
* youngest of the two links. -avalon
*
* Definitely don't do that here. This is from an unregistered
* connect - A1kmm.
*/
sendto_realops_snomask(SNO_GENERAL, L_ALL,
"Attempt to re-introduce server %s from %s",
name, get_server_name(client_p, HIDE_IP));
ilog(L_SERVER, "Attempt to re-introduce server %s from %s",
name, log_client_name(client_p, SHOW_IP));
sendto_one(client_p, "ERROR :Server already exists.");
exit_client(client_p, client_p, client_p, "Server Exists");
return 0;
}
if(has_id(client_p) && (target_p = find_id(client_p->id)) != NULL)
{
sendto_realops_snomask(SNO_GENERAL, L_ALL,
"Attempt to re-introduce SID %s from %s%s",
client_p->id,
EmptyString(client_p->name) ? name : "",
get_server_name(client_p, HIDE_IP));
ilog(L_SERVER, "Attempt to re-introduce SID %s from %s%s",
client_p->id,
EmptyString(client_p->name) ? name : "",
log_client_name(client_p, SHOW_IP));
sendto_one(client_p, "ERROR :SID already exists.");
exit_client(client_p, client_p, client_p, "SID Exists");
return 0;
}
/*
* if we are connecting (Handshake), we already have the name from the
* C:line in client_p->name
*/
strlcpy(client_p->name, name, sizeof(client_p->name));
set_server_gecos(client_p, info);
client_p->hopcount = hop;
server_estab(client_p);
return 0;
}
/*
* ms_server - SERVER message handler
* parv[0] = sender prefix
* parv[1] = servername
* parv[2] = serverinfo/hopcount
* parv[3] = serverinfo
*/
static int
ms_server(struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
{
char info[REALLEN + 1];
/* same size as in s_misc.c */
const char *name;
struct Client *target_p;
struct remote_conf *hub_p;
hook_data_client hdata;
int hop;
int hlined = 0;
int llined = 0;
dlink_node *ptr;
name = parv[1];
hop = atoi(parv[2]);
strlcpy(info, parv[3], sizeof(info));
if((target_p = server_exists(name)))
{
/*
* This link is trying feed me a server that I already have
* access through another path -- multiple paths not accepted
* currently, kill this link immediately!!
*
* Rather than KILL the link which introduced it, KILL the
* youngest of the two links. -avalon
*
* I think that we should exit the link itself, not the introducer,
* and we should always exit the most recently received(i.e. the
* one we are receiving this SERVER for. -A1kmm
*
* You *cant* do this, if you link somewhere, it bursts you a server
* that already exists, then sends you a client burst, you squit the
* server, but you keep getting the burst of clients on a server that
* doesnt exist, although ircd can handle it, its not a realistic
* solution.. --fl_
*/
/* It is behind a host-masked server. Completely ignore the
* server message(don't propagate or we will delink from whoever
* we propagate to). -A1kmm */
if(irccmp(target_p->name, name) && target_p->from == client_p)
return 0;
sendto_one(client_p, "ERROR :Server %s already exists", name);
sendto_realops_snomask(SNO_GENERAL, L_ALL,
"Link %s cancelled, server %s already exists",
get_server_name(client_p, SHOW_IP), name);
ilog(L_SERVER, "Link %s cancelled, server %s already exists",
client_p->name, name);
exit_client(client_p, client_p, &me, "Server Exists");
return 0;
}
/*
* User nicks never have '.' in them and server names
* must always have '.' in them.
*/
if(strchr(name, '.') == NULL)
{
/*
* Server trying to use the same name as a person. Would
* cause a fair bit of confusion. Enough to make it hellish
* for a while and servers to send stuff to the wrong place.
*/
sendto_one(client_p, "ERROR :Nickname %s already exists!", name);
sendto_realops_snomask(SNO_GENERAL, L_ALL,
"Link %s cancelled: Server/nick collision on %s",
get_server_name(client_p, HIDE_IP), name);
ilog(L_SERVER, "Link %s cancelled: Server/nick collision on %s",
client_p->name, name);
exit_client(client_p, client_p, client_p, "Nick as Server");
return 0;
}
/*
* Server is informing about a new server behind
* this link. Create REMOTE server structure,
* add it to list and propagate word to my other
* server links...
*/
if(parc == 1 || EmptyString(info))
{
sendto_one(client_p, "ERROR :No server info specified for %s", name);
return 0;
}
/*
* See if the newly found server is behind a guaranteed
* leaf. If so, close the link.
*
*/
DLINK_FOREACH(ptr, hubleaf_conf_list.head)
{
hub_p = ptr->data;
if(match(hub_p->server, client_p->name) && match(hub_p->host, name))
{
if(hub_p->flags & CONF_HUB)
hlined++;
else
llined++;
}
}
/* Ok, this way this works is
*
* A server can have a CONF_HUB allowing it to introduce servers
* behind it.
*
* connect {
* name = "irc.bighub.net";
* hub_mask="*";
* ...
*
* That would allow "irc.bighub.net" to introduce anything it wanted..
*
* However
*
* connect {
* name = "irc.somehub.fi";
* hub_mask="*";
* leaf_mask="*.edu";
*...
* Would allow this server in finland to hub anything but
* .edu's
*/
/* Ok, check client_p can hub the new server, and make sure it's not a LL */
if(!hlined)
{
/* OOOPs nope can't HUB */
sendto_realops_snomask(SNO_GENERAL, L_ALL, "Non-Hub link %s introduced %s.",
get_server_name(client_p, HIDE_IP), name);
ilog(L_SERVER, "Non-Hub link %s introduced %s.",
client_p->name, name);
exit_client(NULL, client_p, &me, "No matching hub_mask.");
return 0;
}
/* Check for the new server being leafed behind this HUB */
if(llined)
{
/* OOOPs nope can't HUB this leaf */
sendto_realops_snomask(SNO_GENERAL, L_ALL,
"Link %s introduced leafed server %s.",
get_server_name(client_p, HIDE_IP), name);
ilog(L_SERVER, "Link %s introduced leafed server %s.",
client_p->name, name);
exit_client(NULL, client_p, &me, "Leafed Server.");
return 0;
}
if(strlen(name) > HOSTLEN)
{
sendto_realops_snomask(SNO_GENERAL, L_ALL,
"Link %s introduced server with invalid servername %s",
get_server_name(client_p, HIDE_IP), name);
ilog(L_SERVER, "Link %s introduced server with invalid servername %s",
client_p->name, name);
exit_client(NULL, client_p, &me, "Invalid servername introduced.");
return 0;
}
target_p = make_client(client_p);
make_server(target_p);
target_p->hopcount = hop;
strlcpy(target_p->name, name, sizeof(target_p->name));
set_server_gecos(target_p, info);
target_p->serv->up = find_or_add(source_p->name);
if(has_id(source_p))
target_p->serv->upid = source_p->id;
target_p->servptr = source_p;
SetServer(target_p);
dlinkAddTail(target_p, &target_p->node, &global_client_list);
dlinkAddTailAlloc(target_p, &global_serv_list);
add_to_client_hash(target_p->name, target_p);
dlinkAdd(target_p, &target_p->lnode, &target_p->servptr->serv->servers);
sendto_server(client_p, NULL, NOCAPS, NOCAPS,
":%s SERVER %s %d :%s%s",
source_p->name, target_p->name, target_p->hopcount + 1,
IsHidden(target_p) ? "(H) " : "", target_p->info);
sendto_realops_snomask(SNO_EXTERNAL, L_ALL,
"Server %s being introduced by %s", target_p->name, source_p->name);
/* quick, dirty EOB. you know you love it. */
sendto_one(target_p, ":%s PING %s %s", get_id(&me, target_p), me.name, target_p->name);
hdata.client = source_p;
hdata.target = target_p;
call_hook(h_server_introduced, &hdata);
return 0;
}
static int
ms_sid(struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
{
struct Client *target_p;
struct remote_conf *hub_p;
hook_data_client hdata;
dlink_node *ptr;
int hop;
int hlined = 0;
int llined = 0;
hop = atoi(parv[2]);
/* collision on the name? */
if((target_p = server_exists(parv[1])) != NULL)
{
sendto_one(client_p, "ERROR :Server %s already exists", parv[1]);
sendto_realops_snomask(SNO_GENERAL, L_ALL,
"Link %s cancelled, server %s already exists",
get_server_name(client_p, SHOW_IP), parv[1]);
ilog(L_SERVER, "Link %s cancelled, server %s already exists",
client_p->name, parv[1]);
exit_client(NULL, client_p, &me, "Server Exists");
return 0;
}
/* collision on the SID? */
if((target_p = find_id(parv[3])) != NULL)
{
sendto_one(client_p, "ERROR :SID %s already exists", parv[3]);
sendto_realops_snomask(SNO_GENERAL, L_ALL,
"Link %s cancelled, SID %s already exists",
get_server_name(client_p, SHOW_IP), parv[3]);
ilog(L_SERVER, "Link %s cancelled, SID %s already exists",
client_p->name, parv[3]);
exit_client(NULL, client_p, &me, "Server Exists");
return 0;
}
if(bogus_host(parv[1]) || strlen(parv[1]) > HOSTLEN)
{
sendto_one(client_p, "ERROR :Invalid servername");
sendto_realops_snomask(SNO_GENERAL, L_ALL,
"Link %s cancelled, servername %s invalid",
get_server_name(client_p, SHOW_IP), parv[1]);
ilog(L_SERVER, "Link %s cancelled, servername %s invalid",
client_p->name, parv[1]);
exit_client(NULL, client_p, &me, "Bogus server name");
return 0;
}
if(!IsDigit(parv[3][0]) || !IsIdChar(parv[3][1]) ||
!IsIdChar(parv[3][2]) || parv[3][3] != '\0')
{
sendto_one(client_p, "ERROR :Invalid SID");
sendto_realops_snomask(SNO_GENERAL, L_ALL,
"Link %s cancelled, SID %s invalid",
get_server_name(client_p, SHOW_IP), parv[3]);
ilog(L_SERVER, "Link %s cancelled, SID %s invalid",
client_p->name, parv[3]);
exit_client(NULL, client_p, &me, "Bogus SID");
return 0;
}
/* for the directly connected server:
* H: allows it to introduce a server matching that mask
* L: disallows it introducing a server matching that mask
*/
DLINK_FOREACH(ptr, hubleaf_conf_list.head)
{
hub_p = ptr->data;
if(match(hub_p->server, client_p->name) && match(hub_p->host, parv[1]))
{
if(hub_p->flags & CONF_HUB)
hlined++;
else
llined++;
}
}
/* no matching hub_mask */
if(!hlined)
{
sendto_one(client_p, "ERROR :No matching hub_mask");
sendto_realops_snomask(SNO_GENERAL, L_ALL,
"Non-Hub link %s introduced %s.",
get_server_name(client_p, SHOW_IP), parv[1]);
ilog(L_SERVER, "Non-Hub link %s introduced %s.",
client_p->name, parv[1]);
exit_client(NULL, client_p, &me, "No matching hub_mask.");
return 0;
}
/* matching leaf_mask */
if(llined)
{
sendto_one(client_p, "ERROR :Matching leaf_mask");
sendto_realops_snomask(SNO_GENERAL, L_ALL,
"Link %s introduced leafed server %s.",
get_server_name(client_p, SHOW_IP), parv[1]);
ilog(L_SERVER, "Link %s introduced leafed server %s.",
client_p->name, parv[1]);
exit_client(NULL, client_p, &me, "Leafed Server.");
return 0;
}
/* ok, alls good */
target_p = make_client(client_p);
make_server(target_p);
strlcpy(target_p->name, parv[1], sizeof(target_p->name));
target_p->hopcount = atoi(parv[2]);
strcpy(target_p->id, parv[3]);
set_server_gecos(target_p, parv[4]);
target_p->serv->up = find_or_add(source_p->name);
if(has_id(source_p))
target_p->serv->upid = source_p->id;
target_p->servptr = source_p;
SetServer(target_p);
dlinkAddTail(target_p, &target_p->node, &global_client_list);
dlinkAddTailAlloc(target_p, &global_serv_list);
add_to_client_hash(target_p->name, target_p);
add_to_id_hash(target_p->id, target_p);
dlinkAdd(target_p, &target_p->lnode, &target_p->servptr->serv->servers);
sendto_server(client_p, NULL, CAP_TS6, NOCAPS,
":%s SID %s %d %s :%s%s",
source_p->id, target_p->name, target_p->hopcount + 1,
target_p->id, IsHidden(target_p) ? "(H) " : "", target_p->info);
sendto_server(client_p, NULL, NOCAPS, CAP_TS6,
":%s SERVER %s %d :%s%s",
source_p->name, target_p->name, target_p->hopcount + 1,
IsHidden(target_p) ? "(H) " : "", target_p->info);
sendto_realops_snomask(SNO_EXTERNAL, L_ALL,
"Server %s being introduced by %s", target_p->name, source_p->name);
/* quick, dirty EOB. you know you love it. */
sendto_one(target_p, ":%s PING %s %s",
get_id(&me, target_p), me.name, get_id(target_p, target_p));
hdata.client = source_p;
hdata.target = target_p;
call_hook(h_server_introduced, &hdata);
return 0;
}
/* set_server_gecos()
*
* input - pointer to client
* output - none
* side effects - servers gecos field is set
*/
static int
set_server_gecos(struct Client *client_p, const char *info)
{
/* check the info for [IP] */
if(info[0])
{
char *p;
char *s;
char *t;
s = LOCAL_COPY(info);
/* we should only check the first word for an ip */
if((p = strchr(s, ' ')))
*p = '\0';
/* check for a ] which would symbolise an [IP] */
if((t = strchr(s, ']')))
{
/* set s to after the first space */
if(p)
s = ++p;
else
s = NULL;
}
/* no ], put the space back */
else if(p)
*p = ' ';
/* p may have been set to a trailing space, so check s exists and that
* it isnt \0 */
if(s && (*s != '\0'))
{
/* a space? if not (H) could be the last part of info.. */
if((p = strchr(s, ' ')))
*p = '\0';
/* check for (H) which is a hidden server */
if(!strcmp(s, "(H)"))
{
SetHidden(client_p);
/* if there was no space.. theres nothing to set info to */
if(p)
s = ++p;
else
s = NULL;
}
else if(p)
*p = ' ';
/* if there was a trailing space, s could point to \0, so check */
if(s && (*s != '\0'))
{
strlcpy(client_p->info, s, sizeof(client_p->info));
return 1;
}
}
}
strlcpy(client_p->info, "(Unknown Location)", sizeof(client_p->info));
return 1;
}
/*
* bogus_host
*
* inputs - hostname
* output - 1 if a bogus hostname input, 0 if its valid
* side effects - none
*/
int
bogus_host(const char *host)
{
int bogus_server = 0;
const char *s;
int dots = 0;
for(s = host; *s; s++)
{
if(!IsServChar(*s))
{
bogus_server = 1;
break;
}
if('.' == *s)
++dots;
}
if(!dots || bogus_server)
return 1;
return 0;
}
/*
* server_exists()
*
* inputs - servername
* output - 1 if server exists, 0 if doesnt exist
*/
struct Client *
server_exists(const char *servername)
{
struct Client *target_p;
dlink_node *ptr;
DLINK_FOREACH(ptr, global_serv_list.head)
{
target_p = ptr->data;
if(match(target_p->name, servername) || match(servername, target_p->name))
return target_p;
}
return NULL;
}