/*
* IRC - Internet Relay Chat, ircd/m_server.c
* Copyright (C) 1990 Jarkko Oikarinen and
* University of Oulu, Computing Center
*
* See file AUTHORS in IRC package for additional names of
* the programmers.
*
* 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 1, 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* $Id: m_server.c 880 2004-11-20 05:30:12Z r33d $
*/
/*
* m_functions execute protocol messages on this server:
*
* cptr is always NON-NULL, pointing to a *LOCAL* client
* structure (with an open socket connected!). This
* identifies the physical socket where the message
* originated (or which caused the m_function to be
* executed--some m_functions may call others...).
*
* sptr is the source of the message, defined by the
* prefix part of the message if present. If not
* or prefix not found, then sptr==cptr.
*
* (!IsServer(cptr)) => (cptr == sptr), because
* prefixes are taken *only* from servers...
*
* (IsServer(cptr))
* (sptr == cptr) => the message didn't
* have the prefix.
*
* (sptr != cptr && IsServer(sptr) means
* the prefix specified servername. (?)
*
* (sptr != cptr && !IsServer(sptr) means
* that message originated from a remote
* user (not local).
*
* combining
*
* (!IsServer(sptr)) means that, sptr can safely
* taken as defining the target structure of the
* message in this server.
*
* *Always* true (if 'parse' and others are working correct):
*
* 1) sptr->from == cptr (note: cptr->from == cptr)
*
* 2) MyConnect(sptr) <=> sptr == cptr (e.g. sptr
* *cannot* be a local connection, unless it's
* actually cptr!). [MyConnect(x) should probably
* be defined as (x == x->from) --msa ]
*
* parc number of variable parameter strings (if zero,
* parv is allowed to be NULL)
*
* parv a NULL terminated list of parameter pointers,
*
* parv[0], sender (prefix string), if not present
* this points to an empty string.
* parv[1]...parv[parc-1]
* pointers to additional parameters
* parv[parc] == NULL, *always*
*
* note: it is guaranteed that parv[0]..parv[parc-1] are all
* non-NULL pointers.
*/
#include "config.h"
#include "client.h"
#include "hash.h"
#include "ircd.h"
#include "ircd_log.h"
#include "ircd_features.h"
#include "ircd_reply.h"
#include "ircd_string.h"
#include "jupe.h"
#include "list.h"
#include "match.h"
#include "map.h"
#include "msg.h"
#include "numeric.h"
#include "numnicks.h"
#include "querycmds.h"
#include "s_bsd.h"
#include "s_conf.h"
#include "s_debug.h"
#include "s_misc.h"
#include "s_serv.h"
#include "send.h"
#include "userload.h"
#include <assert.h>
#include <stdlib.h>
#include <string.h>
/*
* mr_server - registration message handler
*
* parv[0] = sender prefix
* parv[1] = servername
* parv[2] = hopcount
* parv[3] = start timestamp
* parv[4] = link timestamp
* parv[5] = major protocol version: P09/P10
* parv[parc-1] = serverinfo
* If cptr is P10:
* parv[6] = "YMM", where 'Y' is the server numeric and "MM" is the
* numeric nick mask of this server.
* parv[7] = +hs (h == hub, s == service)
*/
int mr_server(struct Client* cptr, struct Client* sptr, int parc, char* parv[])
{
char* ch;
int i;
char info[REALLEN + 1];
char* host;
struct Client* acptr;
struct Client* bcptr;
struct Client* LHcptr = 0;
struct ConfItem* aconf = 0;
struct ConfItem* lhconf = 0;
struct Jupe* ajupe = 0;
int hop;
int ret;
int active_lh_line = 0;
unsigned short prot;
time_t start_timestamp;
time_t timestamp = 0;
time_t recv_time;
time_t ghost = 0;
if (IsUserPort(cptr))
return exit_client_msg(cptr, cptr, &me,
"Cannot connect a server to a user port");
recv_time = TStime();
info[0] = '\0';
if (parc < 8)
{
need_more_params(sptr, "SERVER");
return exit_client(cptr, cptr, &me, "Need more parameters");
}
host = parv[1];
if ((ajupe = jupe_find(host)) && JupeIsActive(ajupe))
return exit_client_msg(cptr, sptr, &me, "Juped: %s", JupeReason(ajupe));
log_write(LS_NETWORK, L_NOTICE, LOG_NOSNOTICE, "SERVER: %s %s[%s]", parv[1],
cli_sockhost(cptr), cli_sock_ip(cptr));
/*
* Detect protocol
*/
if (strlen(parv[5]) != 3 || (parv[5][0] != 'P' && parv[5][0] != 'J'))
return exit_client_msg(cptr, sptr, &me, "Bogus protocol (%s)", parv[5]);
if (!IsServer(cptr)) /* Don't allow silently connecting a server */
*parv[5] = 'J';
if (*parv[7] == '+') {
for (ch = parv[7] + 1; *ch; ch++)
switch (*ch) {
case 'h':
SetHub(cptr);
break;
case 's':
SetService(cptr);
break;
}
}
prot = atoi(parv[5] + 1);
if (prot > atoi(MAJOR_PROTOCOL))
prot = atoi(MAJOR_PROTOCOL);
/*
* Because the previous test is only in 2.10, the following is needed
* till all servers are 2.10:
*/
if (IsServer(cptr) && prot > Protocol(cptr))
prot = Protocol(cptr);
hop = atoi(parv[2]);
start_timestamp = atoi(parv[3]);
timestamp = atoi(parv[4]);
Debug((DEBUG_INFO, "Got SERVER %s with timestamp [%s] age %Tu (%Tu)",
host, parv[4], start_timestamp, cli_serv(&me)->timestamp));
if ((timestamp < OLDEST_TS || (hop == 1 && start_timestamp < OLDEST_TS)))
{
return exit_client_msg(cptr, sptr, &me,
"Bogus timestamps (%s %s)", parv[3], parv[4]);
}
ircd_strncpy(info, parv[parc - 1], REALLEN);
info[REALLEN] = '\0';
if (prot < atoi(MINOR_PROTOCOL)) {
sendto_opmask_butone(0, SNO_OLDSNO, "Got incompatible protocol version "
"(%s) from %s", parv[5], cli_name(cptr));
return exit_new_server(cptr, sptr, host, timestamp,
"Incompatible protocol: %s", parv[5]);
}
/*
* Check for "FRENCH " infection ;-) (actually this should
* be replaced with routine to check the hostname syntax in
* general). [ This check is still needed, even after the parse
* is fixed, because someone can send "SERVER :foo bar " ].
* Also, changed to check other "difficult" characters, now
* that parse lets all through... --msa
*/
if (strlen(host) > HOSTLEN)
host[HOSTLEN] = '\0';
for (ch = host; *ch; ch++) {
if (*ch <= ' ' || *ch > '~')
break;
}
if (*ch || !strchr(host, '.')) {
sendto_opmask_butone(0, SNO_OLDSNO, "Bogus server name (%s) from %s",
host, cli_name(cptr));
return exit_client_msg(cptr, cptr, &me, "Bogus server name (%s)", host);
}
if (IsServer(cptr))
{
/*
* A local server introduces a new server behind this link.
* Check if this is allowed according L:, H: and Q: lines.
*/
if (info[0] == '\0')
return exit_client_msg(cptr, cptr, &me,
"No server info specified for %s", host);
/*
* See if the newly found server is behind a guaranteed
* leaf (L-line). If so, close the link.
*/
if ((lhconf = find_conf_byhost(cli_confs(cptr), cli_name(cptr), CONF_LEAF)) &&
(!lhconf->port || (hop > lhconf->port)))
{
/*
* L: lines normally come in pairs, here we try to
* make sure that the oldest link is squitted, not
* both.
*/
active_lh_line = 1;
if (timestamp <= cli_serv(cptr)->timestamp)
LHcptr = 0; /* Kill incoming server */
else
LHcptr = cptr; /* Squit ourselfs */
}
else if (!(lhconf = find_conf_byname(cli_confs(cptr), cli_name(cptr), CONF_HUB)) ||
(lhconf->port && (hop > lhconf->port)))
{
struct Client *ac3ptr;
active_lh_line = 2;
/* Look for net junction causing this: */
LHcptr = 0; /* incoming server */
if (*parv[5] != 'J') {
for (ac3ptr = sptr; ac3ptr != &me; ac3ptr = cli_serv(ac3ptr)->up) {
if (IsJunction(ac3ptr)) {
LHcptr = ac3ptr;
break;
}
}
}
}
}
if (IsUnknown(cptr) || IsHandshake(cptr))
{
const char* encr;
/*
* A local link that is still in undefined state wants
* to be a SERVER. Check if this is allowed and change
* status accordingly...
*/
/*
* If there is more then one server on the same machine
* that we try to connect to, it could be that the /CONNECT
* <mask> caused this connect to be put at the wrong place
* in the hashtable. --Run
* Same thing for Unknown connections that first send NICK.
* --Xorath
* Better check if the two strings are (caseless) identical
* and not mess with hash internals.
* --Nemesi
*/
if (!EmptyString(cli_name(cptr)) &&
(IsUnknown(cptr) || IsHandshake(cptr)) &&
0 != ircd_strcmp(cli_name(cptr), host))
hChangeClient(cptr, host);
ircd_strncpy(cli_name(cptr), host, HOSTLEN);
ircd_strncpy(cli_info(cptr), info[0] ? info : cli_name(&me), REALLEN);
cli_hopcount(cptr) = hop;
/* check connection rules */
if (0 != conf_eval_crule(host, CRULE_ALL)) {
ServerStats->is_ref++;
sendto_opmask_butone(0, SNO_OLDSNO, "Refused connection from %s.", cli_name(cptr));
return exit_client(cptr, cptr, &me, "Disallowed by connection rule");
}
if (conf_check_server(cptr)) {
++ServerStats->is_ref;
sendto_opmask_butone(0, SNO_OLDSNO, "Received unauthorized connection "
"from %s [%s]", cli_name(cptr), ircd_ntoa((const char*)&cli_ip(cptr)));
log_write(LS_NETWORK, L_NOTICE, LOG_NOSNOTICE, "Received unauthorized "
"connection from %C [%s]", cptr,
ircd_ntoa((const char *)&(cli_ip(cptr))));
return exit_client(cptr, cptr, &me, "No C:line");
}
update_load();
if (!(aconf = find_conf_byname(cli_confs(cptr), host, CONF_SERVER))) {
++ServerStats->is_ref;
sendto_opmask_butone(0, SNO_OLDSNO, "Access denied. No conf line for "
"server %s", cli_name(cptr));
return exit_client_msg(cptr, cptr, &me,
"Access denied. No conf line for server %s", cli_name(cptr));
}
encr = cli_passwd(cptr);
if (*aconf->passwd && !!strcmp(aconf->passwd, encr)) {
++ServerStats->is_ref;
sendto_opmask_butone(0, SNO_OLDSNO, "Access denied (passwd mismatch) %s",
cli_name(cptr));
return exit_client_msg(cptr, cptr, &me,
"No Access (passwd mismatch) %s", cli_name(cptr));
}
memset(cli_passwd(cptr), 0, sizeof(cli_passwd(cptr)));
if (!feature_bool(FEAT_HUB)) {
for (i = 0; i <= HighestFd; i++)
if (LocalClientArray[i] && IsServer(LocalClientArray[i])) {
active_lh_line = 3;
LHcptr = 0;
break;
}
}
}
/*
* We want to find IsConnecting() and IsHandshake() too,
* use FindClient().
* The second finds collisions with numeric representation of existing
* servers - these shouldn't happen anymore when all upgraded to 2.10.
* -- Run
*/
while ((acptr = FindClient(host)) ||
(parc > 7 && (acptr = FindNServer(parv[6]))))
{
/*
* This link is trying feed me a server that I already have
* access through another path
*
* Do not allow Uworld to do this.
* Do not allow servers that are juped.
* Do not allow servers that have older link timestamps
* then this try.
* Do not allow servers that use the same numeric as an existing
* server, but have a different name.
*
* If my ircd.conf sucks, I can try to connect to myself:
*/
if (acptr == &me)
return exit_client_msg(cptr, cptr, &me, "nick collision with me (%s), check server number in M:?", host);
/*
* Detect wrong numeric.
*/
if (0 != ircd_strcmp(cli_name(acptr), host)) {
sendcmdto_serv_butone(&me, CMD_WALLOPS, cptr,
":SERVER Numeric Collision: %s != %s",
cli_name(acptr), host);
return exit_client_msg(cptr, cptr, &me,
"NUMERIC collision between %s and %s."
" Is your server numeric correct ?", host, cli_name(acptr));
}
/*
* Kill our try, if we had one.
*/
if (IsConnecting(acptr))
{
if (!active_lh_line && exit_client(cptr, acptr, &me,
"Just connected via another link") == CPTR_KILLED)
return CPTR_KILLED;
/*
* We can have only ONE 'IsConnecting', 'IsHandshake' or
* 'IsServer', because new 'IsConnecting's are refused to
* the same server if we already had it.
*/
break;
}
/*
* Avoid other nick collisions...
* This is a doubtfull test though, what else would it be
* when it has a server.name ?
*/
else if (!IsServer(acptr) && !IsHandshake(acptr))
return exit_client_msg(cptr, cptr, &me,
"Nickname %s already exists!", host);
/*
* Our new server might be a juped server,
* or someone trying abuse a second Uworld:
*/
else if (IsServer(acptr) && (0 == ircd_strncmp(cli_info(acptr), "JUPE", 4) ||
find_conf_byhost(cli_confs(cptr), cli_name(acptr), CONF_UWORLD)))
{
if (!IsServer(sptr))
return exit_client(cptr, sptr, &me, cli_info(acptr));
sendcmdto_serv_butone(&me, CMD_WALLOPS, cptr,
":Received :%s SERVER %s from %s !?!", parv[0],
parv[1], cli_name(cptr));
return exit_new_server(cptr, sptr, host, timestamp, "%s", cli_info(acptr));
}
/*
* Of course we find the handshake this link was before :)
*/
else if (IsHandshake(acptr) && acptr == cptr)
break;
/*
* Here we have a server nick collision...
* We don't want to kill the link that was last /connected,
* but we neither want to kill a good (old) link.
* Therefor we kill the second youngest link.
*/
if (1)
{
struct Client* c2ptr = 0;
struct Client* c3ptr = acptr;
struct Client* ac2ptr;
struct Client* ac3ptr;
/* Search youngest link: */
for (ac3ptr = acptr; ac3ptr != &me; ac3ptr = cli_serv(ac3ptr)->up)
if (cli_serv(ac3ptr)->timestamp > cli_serv(c3ptr)->timestamp)
c3ptr = ac3ptr;
if (IsServer(sptr))
{
for (ac3ptr = sptr; ac3ptr != &me; ac3ptr = cli_serv(ac3ptr)->up)
if (cli_serv(ac3ptr)->timestamp > cli_serv(c3ptr)->timestamp)
c3ptr = ac3ptr;
}
if (timestamp > cli_serv(c3ptr)->timestamp)
{
c3ptr = 0;
c2ptr = acptr; /* Make sure they differ */
}
/* Search second youngest link: */
for (ac2ptr = acptr; ac2ptr != &me; ac2ptr = cli_serv(ac2ptr)->up)
if (ac2ptr != c3ptr &&
cli_serv(ac2ptr)->timestamp >
(c2ptr ? cli_serv(c2ptr)->timestamp : timestamp))
c2ptr = ac2ptr;
if (IsServer(sptr))
{
for (ac2ptr = sptr; ac2ptr != &me; ac2ptr = cli_serv(ac2ptr)->up)
if (ac2ptr != c3ptr &&
cli_serv(ac2ptr)->timestamp >
(c2ptr ? cli_serv(c2ptr)->timestamp : timestamp))
c2ptr = ac2ptr;
}
if (c3ptr && timestamp > (c2ptr ? cli_serv(c2ptr)->timestamp : timestamp))
c2ptr = 0;
/* If timestamps are equal, decide which link to break
* by name.
*/
if ((c2ptr ? cli_serv(c2ptr)->timestamp : timestamp) ==
(c3ptr ? cli_serv(c3ptr)->timestamp : timestamp))
{
char* n2;
char* n2up;
char* n3;
char* n3up;
if (c2ptr)
{
n2 = cli_name(c2ptr);
n2up = MyConnect(c2ptr) ? cli_name(&me) : cli_name(cli_serv(c2ptr)->up);
}
else
{
n2 = host;
n2up = IsServer(sptr) ? cli_name(sptr) : cli_name(&me);
}
if (c3ptr)
{
n3 = cli_name(c3ptr);
n3up = MyConnect(c3ptr) ? cli_name(&me) : cli_name(cli_serv(c3ptr)->up);
}
else
{
n3 = host;
n3up = IsServer(sptr) ? cli_name(sptr) : cli_name(&me);
}
if (strcmp(n2, n2up) > 0)
n2 = n2up;
if (strcmp(n3, n3up) > 0)
n3 = n3up;
if (strcmp(n3, n2) > 0)
{
ac2ptr = c2ptr;
c2ptr = c3ptr;
c3ptr = ac2ptr;
}
}
/* Now squit the second youngest link: */
if (!c2ptr)
return exit_new_server(cptr, sptr, host, timestamp,
"server %s already exists and is %ld seconds younger.",
host, (long)cli_serv(acptr)->timestamp - (long)timestamp);
else if (cli_from(c2ptr) == cptr || IsServer(sptr))
{
struct Client *killedptrfrom = cli_from(c2ptr);
if (active_lh_line)
{
/*
* If the L: or H: line also gets rid of this link,
* we sent just one squit.
*/
if (LHcptr && a_kills_b_too(LHcptr, c2ptr))
break;
/*
* If breaking the loop here solves the L: or H:
* line problem, we don't squit that.
*/
if (cli_from(c2ptr) == cptr || (LHcptr && a_kills_b_too(c2ptr, LHcptr)))
active_lh_line = 0;
else
{
/*
* If we still have a L: or H: line problem,
* we prefer to squit the new server, solving
* loop and L:/H: line problem with only one squit.
*/
LHcptr = 0;
break;
}
}
/*
* If the new server was introduced by a server that caused a
* Ghost less then 20 seconds ago, this is probably also
* a Ghost... (20 seconds is more then enough because all
* SERVER messages are at the beginning of a net.burst). --Run
*/
if (CurrentTime - cli_serv(cptr)->ghost < 20)
{
killedptrfrom = cli_from(acptr);
if (exit_client(cptr, acptr, &me, "Ghost loop") == CPTR_KILLED)
return CPTR_KILLED;
}
else if (exit_client_msg(cptr, c2ptr, &me,
"Loop <-- %s (new link is %ld seconds younger)", host,
(c3ptr ? (long)cli_serv(c3ptr)->timestamp : timestamp) -
(long)cli_serv(c2ptr)->timestamp) == CPTR_KILLED)
return CPTR_KILLED;
/*
* Did we kill the incoming server off already ?
*/
if (killedptrfrom == cptr)
return 0;
}
else
{
if (active_lh_line)
{
if (LHcptr && a_kills_b_too(LHcptr, acptr))
break;
if (cli_from(acptr) == cptr || (LHcptr && a_kills_b_too(acptr, LHcptr)))
active_lh_line = 0;
else
{
LHcptr = 0;
break;
}
}
/*
* We can't believe it is a lagged server message
* when it directly connects to us...
* kill the older link at the ghost, rather then
* at the second youngest link, assuming it isn't
* a REAL loop.
*/
ghost = CurrentTime; /* Mark that it caused a ghost */
if (exit_client(cptr, acptr, &me, "Ghost") == CPTR_KILLED)
return CPTR_KILLED;
break;
}
}
}
if (active_lh_line)
{
if (LHcptr == 0) {
return exit_new_server(cptr, sptr, host, timestamp,
(active_lh_line == 2) ? "Non-Hub link %s <- %s(%s), check H:" :
"Leaf-only link %s <- %s(%s), check L:",
cli_name(cptr), host,
lhconf ? (lhconf->name ? lhconf->name : "*") : "!");
}
else
{
int killed = a_kills_b_too(LHcptr, sptr);
if (active_lh_line < 3)
{
if (exit_client_msg(cptr, LHcptr, &me,
(active_lh_line == 2) ? "Non-Hub link %s <- %s(%s), check H:" :
"Leaf-only link %s <- %s(%s), check L:",
cli_name(cptr), host,
lhconf ? (lhconf->name ? lhconf->name : "*") : "!") == CPTR_KILLED)
return CPTR_KILLED;
}
else
{
ServerStats->is_ref++;
if (exit_client(cptr, LHcptr, &me, "I'm a leaf, define HUB") == CPTR_KILLED)
return CPTR_KILLED;
}
/*
* Did we kill the incoming server off already ?
*/
if (killed)
return 0;
}
}
if (IsServer(cptr))
{
/*
* 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...
*/
acptr = make_client(cptr, STAT_SERVER);
make_server(acptr);
cli_serv(acptr)->prot = prot;
cli_serv(acptr)->timestamp = timestamp;
cli_hopcount(acptr) = hop;
ircd_strncpy(cli_name(acptr), host, HOSTLEN);
ircd_strncpy(cli_info(acptr), info, REALLEN);
cli_serv(acptr)->up = sptr;
cli_serv(acptr)->updown = add_dlink(&(cli_serv(sptr))->down, acptr);
/* Use cptr, because we do protocol 9 -> 10 translation
for numeric nicks ! */
SetServerYXX(cptr, acptr, parv[6]);
Count_newremoteserver(UserStats);
if (Protocol(acptr) < 10)
SetFlag(acptr, FLAG_TS8);
add_client_to_list(acptr);
hAddClient(acptr);
map_update(acptr);
if (*parv[5] == 'J')
{
SetBurst(acptr);
sendto_opmask_butone(0, SNO_NETWORK, "Net junction: %s %s",
cli_name(sptr), cli_name(acptr));
SetJunction(acptr);
}
/*
* Old sendto_serv_but_one() call removed because we now need to send
* different names to different servers (domain name matching).
*
* Personally, I think this is bogus; it's a feature we don't use here.
* -Kev
*/
for (i = 0; i <= HighestFd; i++)
{
if (!(bcptr = LocalClientArray[i]) || !IsServer(bcptr) ||
bcptr == cptr || IsMe(bcptr))
continue;
if (0 == match(cli_name(&me), cli_name(acptr)))
continue;
sendcmdto_one(sptr, CMD_SERVER, bcptr, "%s %d 0 %s %s %s%s +%s%s :%s",
cli_name(acptr), hop + 1, parv[4], parv[5],
NumServCap(acptr), IsHub(acptr) ? "h" : "",
IsService(acptr) ? "s" : "", cli_info(acptr));
}
return 0;
}
if (IsUnknown(cptr) || IsHandshake(cptr))
{
make_server(cptr);
cli_serv(cptr)->timestamp = timestamp;
cli_serv(cptr)->prot = prot;
cli_serv(cptr)->ghost = ghost;
SetServerYXX(cptr, cptr, parv[6]);
if (start_timestamp > OLDEST_TS)
{
Debug((DEBUG_DEBUG, "My start time: %Tu; other's start time: %Tu",
cli_serv(&me)->timestamp, start_timestamp));
Debug((DEBUG_DEBUG, "Receive time: %Tu; received timestamp: %Tu; "
"difference %ld", recv_time, timestamp, timestamp - recv_time));
if (feature_bool(FEAT_RELIABLE_CLOCK)) {
if (start_timestamp < cli_serv(&me)->timestamp)
cli_serv(&me)->timestamp = start_timestamp;
if (IsUnknown(cptr))
cli_serv(cptr)->timestamp = TStime();
} else {
if (start_timestamp < cli_serv(&me)->timestamp) {
sendto_opmask_butone(0, SNO_OLDSNO, "got earlier start time: "
"%Tu < %Tu", start_timestamp,
cli_serv(&me)->timestamp);
cli_serv(&me)->timestamp = start_timestamp;
TSoffset += timestamp - recv_time;
sendto_opmask_butone(0, SNO_OLDSNO, "clock adjusted by adding %d",
(int)(timestamp - recv_time));
} else if ((start_timestamp > cli_serv(&me)->timestamp) &&
IsUnknown(cptr))
cli_serv(cptr)->timestamp = TStime();
else if (timestamp != recv_time) {
/*
* Equal start times, we have a collision. Let the connected-to
* server decide. This assumes leafs issue more than half of the
* connection attempts.
*/
if (IsUnknown(cptr))
cli_serv(cptr)->timestamp = TStime();
else if (IsHandshake(cptr)) {
sendto_opmask_butone(0, SNO_OLDSNO, "clock adjusted by adding %d",
(int)(timestamp - recv_time));
TSoffset += timestamp - recv_time;
}
}
}
}
ret = server_estab(cptr, aconf);
}
else
ret = 0;
if (feature_bool(FEAT_RELIABLE_CLOCK) &&
abs(cli_serv(cptr)->timestamp - recv_time) > 30) {
sendto_opmask_butone(0, SNO_OLDSNO, "Connected to a net with a "
"timestamp-clock difference of %Td seconds! "
"Used SETTIME to correct this.",
timestamp - recv_time);
sendcmdto_prio_one(&me, CMD_SETTIME, cptr, "%Tu :%s", TStime(),
cli_name(&me));
}
return ret;
}
/*
* ms_server - server message handler
*
* parv[0] = sender prefix
* parv[1] = servername
* parv[2] = hopcount
* parv[3] = start timestamp
* parv[4] = link timestamp
* parv[5] = major protocol version: P09/P10
* parv[parc-1] = serverinfo
* If cptr is P10:
* parv[6] = "YMM", where 'Y' is the server numeric and "MM" is the
* numeric nick mask of this server.
* parv[7] = +hs (h == hub, s == service)
*/
int ms_server(struct Client* cptr, struct Client* sptr, int parc, char* parv[])
{
char* ch;
int i;
char info[REALLEN + 1];
char* host;
struct Client* acptr;
struct Client* bcptr;
struct Client* LHcptr = 0;
struct ConfItem* aconf = 0;
struct ConfItem* lhconf = 0;
int hop;
int ret;
int active_lh_line = 0;
unsigned short prot;
unsigned char is_hub = 0;
unsigned char is_service = 0;
time_t start_timestamp;
time_t timestamp = 0;
time_t recv_time;
time_t ghost = 0;
if (IsUserPort(cptr))
return exit_client_msg(cptr, cptr, &me,
"Cannot connect a server to a user port");
recv_time = TStime();
info[0] = '\0';
if (parc < 7)
{
return need_more_params(sptr, "SERVER");
return exit_client(cptr, cptr, &me, "Need more parameters");
}
host = parv[1];
/*
* Detect protocol
*/
if (strlen(parv[5]) != 3 || (parv[5][0] != 'P' && parv[5][0] != 'J'))
return exit_client_msg(cptr, sptr, &me, "Bogus protocol (%s)", parv[5]);
if (!IsServer(cptr)) /* Don't allow silently connecting a server */
*parv[5] = 'J';
if (*parv[7] == '+') {
for (ch = parv[7] + 1; *ch; ch++)
switch (*ch) {
case 'h':
is_hub = 1;
break;
case 's':
is_service = 1;
break;
}
}
prot = atoi(parv[5] + 1);
if (prot > atoi(MAJOR_PROTOCOL))
prot = atoi(MAJOR_PROTOCOL);
/*
* Because the previous test is only in 2.10, the following is needed
* till all servers are 2.10:
*/
if (IsServer(cptr) && prot > Protocol(cptr))
prot = Protocol(cptr);
hop = atoi(parv[2]);
start_timestamp = atoi(parv[3]);
timestamp = atoi(parv[4]);
Debug((DEBUG_INFO, "Got SERVER %s with timestamp [%s] age %Tu (%Tu)",
host, parv[4], start_timestamp, cli_serv(&me)->timestamp));
if ((timestamp < OLDEST_TS || (hop == 1 && start_timestamp < OLDEST_TS)))
{
return exit_client_msg(cptr, sptr, &me,
"Bogus timestamps (%s %s)", parv[3], parv[4]);
}
ircd_strncpy(info, parv[parc - 1], REALLEN);
info[REALLEN] = '\0';
if (prot < atoi(MINOR_PROTOCOL)) {
sendto_opmask_butone(0, SNO_OLDSNO, "Got incompatible protocol version "
"(%s) from %s", parv[5], cli_name(cptr));
return exit_new_server(cptr, sptr, host, timestamp,
"Incompatible protocol: %s", parv[5]);
}
/*
* Check for "FRENCH " infection ;-) (actually this should
* be replaced with routine to check the hostname syntax in
* general). [ This check is still needed, even after the parse
* is fixed, because someone can send "SERVER :foo bar " ].
* Also, changed to check other "difficult" characters, now
* that parse lets all through... --msa
*/
if (strlen(host) > HOSTLEN)
host[HOSTLEN] = '\0';
for (ch = host; *ch; ch++)
if (*ch <= ' ' || *ch > '~')
break;
if (*ch || !strchr(host, '.')) {
sendto_opmask_butone(0, SNO_OLDSNO, "Bogus server name (%s) from %s",
host, cli_name(cptr));
return exit_client_msg(cptr, cptr, &me, "Bogus server name (%s)", host);
}
if (IsServer(cptr))
{
/*
* A local server introduces a new server behind this link.
* Check if this is allowed according L:, H: and Q: lines.
*/
if (info[0] == '\0')
return exit_client_msg(cptr, cptr, &me,
"No server info specified for %s", host);
/*
* See if the newly found server is behind a guaranteed
* leaf (L-line). If so, close the link.
*/
if ((lhconf = find_conf_byhost(cli_confs(cptr), cli_name(cptr), CONF_LEAF)) &&
(!lhconf->port || (hop > lhconf->port)))
{
/*
* L: lines normally come in pairs, here we try to
* make sure that the oldest link is squitted, not
* both.
*/
active_lh_line = 1;
if (timestamp <= cli_serv(cptr)->timestamp)
LHcptr = 0; /* Kill incoming server */
else
LHcptr = cptr; /* Squit ourselfs */
}
else if (!(lhconf = find_conf_byname(cli_confs(cptr), cli_name(cptr), CONF_HUB)) ||
(lhconf->port && (hop > lhconf->port)) ||
(!BadPtr(lhconf->host) && match(lhconf->host, parv[1])))
{
struct Client *ac3ptr;
active_lh_line = 2;
/* Look for net junction causing this: */
LHcptr = 0; /* incoming server */
if (*parv[5] != 'J') {
for (ac3ptr = sptr; ac3ptr != &me; ac3ptr = cli_serv(ac3ptr)->up) {
if (IsJunction(ac3ptr)) {
LHcptr = ac3ptr;
break;
}
}
}
}
}
if (IsUnknown(cptr) || IsHandshake(cptr))
{
const char* encr;
/*
* A local link that is still in undefined state wants
* to be a SERVER. Check if this is allowed and change
* status accordingly...
*/
/*
* If there is more then one server on the same machine
* that we try to connect to, it could be that the /CONNECT
* <mask> caused this connect to be put at the wrong place
* in the hashtable. --Run
* Same thing for Unknown connections that first send NICK.
* --Xorath
* Better check if the two strings are (caseless) identical
* and not mess with hash internals.
* --Nemesi
*/
if ((!(EmptyString(cli_name(cptr))))
&& (IsUnknown(cptr) || IsHandshake(cptr))
&& 0 != ircd_strcmp(cli_name(cptr), host))
hChangeClient(cptr, host);
ircd_strncpy(cli_name(cptr), host, HOSTLEN);
ircd_strncpy(cli_info(cptr), info[0] ? info : cli_name(&me), REALLEN);
cli_hopcount(cptr) = hop;
/* check connection rules */
if (0 != conf_eval_crule(host, CRULE_ALL)) {
ServerStats->is_ref++;
sendto_opmask_butone(0, SNO_OLDSNO, "Refused connection from %s.", cli_name(cptr));
return exit_client(cptr, cptr, &me, "Disallowed by connection rule");
}
if (conf_check_server(cptr)) {
++ServerStats->is_ref;
sendto_opmask_butone(0, SNO_OLDSNO, "Received unauthorized connection "
"from %s.", cli_name(cptr));
log_write(LS_NETWORK, L_NOTICE, LOG_NOSNOTICE, "Received unauthorized "
"connection from %C [%s]", cptr,
ircd_ntoa((const char *)&(cli_ip(cptr))));
return exit_client(cptr, cptr, &me, "No C conf lines");
}
host = cli_name(cptr);
update_load();
if (!(aconf = find_conf_byname(cli_confs(cptr), host, CONF_SERVER))) {
++ServerStats->is_ref;
sendto_opmask_butone(0, SNO_OLDSNO, "Access denied. No conf line for "
"server %s", cli_name(cptr));
return exit_client_msg(cptr, cptr, &me,
"Access denied. No conf line for server %s", cli_name(cptr));
}
encr = cli_passwd(cptr);
if (*(aconf->passwd) && !!strcmp(aconf->passwd, encr)) {
++ServerStats->is_ref;
sendto_opmask_butone(0, SNO_OLDSNO, "Access denied (passwd mismatch) %s",
cli_name(cptr));
return exit_client_msg(cptr, cptr, &me,
"No Access (passwd mismatch) %s", cli_name(cptr));
}
memset(cli_passwd(cptr), 0, sizeof(cli_passwd(cptr)));
if (!feature_bool(FEAT_HUB)) {
for (i = 0; i <= HighestFd; i++)
if (LocalClientArray[i] && IsServer(LocalClientArray[i])) {
active_lh_line = 3;
LHcptr = 0;
break;
}
}
}
/*
* We want to find IsConnecting() and IsHandshake() too,
* use FindClient().
* The second finds collisions with numeric representation of existing
* servers - these shouldn't happen anymore when all upgraded to 2.10.
* -- Run
*/
while ((acptr = FindClient(host)) ||
(parc > 7 && (acptr = FindNServer(parv[6]))))
{
/*
* This link is trying feed me a server that I already have
* access through another path
*
* Do not allow Uworld to do this.
* Do not allow servers that are juped.
* Do not allow servers that have older link timestamps
* then this try.
* Do not allow servers that use the same numeric as an existing
* server, but have a different name.
*
* If my ircd.conf sucks, I can try to connect to myself:
*/
if (acptr == &me)
return exit_client_msg(cptr, cptr, &me,
"nick collision with me, check server number in M:? (%s)", host);
/*
* Detect wrong numeric.
*/
if (0 != ircd_strcmp(cli_name(acptr), host))
{
sendcmdto_serv_butone(&me, CMD_WALLOPS, cptr,
":SERVER Numeric Collision: %s != %s", cli_name(acptr),
host);
return exit_client_msg(cptr, cptr, &me,
"NUMERIC collision between %s and %s."
" Is your server numeric correct ?", host, cli_name(acptr));
}
/*
* Kill our try, if we had one.
*/
if (IsConnecting(acptr))
{
if (!active_lh_line && exit_client(cptr, acptr, &me,
"Just connected via another link") == CPTR_KILLED)
return CPTR_KILLED;
/*
* We can have only ONE 'IsConnecting', 'IsHandshake' or
* 'IsServer', because new 'IsConnecting's are refused to
* the same server if we already had it.
*/
break;
}
/*
* Avoid other nick collisions...
* This is a doubtfull test though, what else would it be
* when it has a server.name ?
*/
else if (!IsServer(acptr) && !IsHandshake(acptr))
return exit_client_msg(cptr, cptr, &me,
"Nickname %s already exists!", host);
/*
* Our new server might be a juped server,
* or someone trying abuse a second Uworld:
*/
else if (IsServer(acptr) && (0 == ircd_strncmp(cli_info(acptr), "JUPE", 4) ||
find_conf_byhost(cli_confs(cptr), cli_name(acptr), CONF_UWORLD)))
{
if (!IsServer(sptr))
return exit_client(cptr, sptr, &me, cli_info(acptr));
sendcmdto_one(&me, CMD_WALLOPS, cptr, ":Received :%s SERVER %s "
"from %s !?!", parv[0], parv[1], cli_name(cptr));
return exit_new_server(cptr, sptr, host, timestamp, "%s", cli_info(acptr));
}
/*
* Of course we find the handshake this link was before :)
*/
else if (IsHandshake(acptr) && acptr == cptr)
break;
/*
* Here we have a server nick collision...
* We don't want to kill the link that was last /connected,
* but we neither want to kill a good (old) link.
* Therefor we kill the second youngest link.
*/
if (1)
{
struct Client* c2ptr = 0;
struct Client* c3ptr = acptr;
struct Client* ac2ptr;
struct Client* ac3ptr;
/* Search youngest link: */
for (ac3ptr = acptr; ac3ptr != &me; ac3ptr = cli_serv(ac3ptr)->up)
if (cli_serv(ac3ptr)->timestamp > cli_serv(c3ptr)->timestamp)
c3ptr = ac3ptr;
if (IsServer(sptr))
{
for (ac3ptr = sptr; ac3ptr != &me; ac3ptr = cli_serv(ac3ptr)->up)
if (cli_serv(ac3ptr)->timestamp > cli_serv(c3ptr)->timestamp)
c3ptr = ac3ptr;
}
if (timestamp > cli_serv(c3ptr)->timestamp)
{
c3ptr = 0;
c2ptr = acptr; /* Make sure they differ */
}
/* Search second youngest link: */
for (ac2ptr = acptr; ac2ptr != &me; ac2ptr = cli_serv(ac2ptr)->up)
if (ac2ptr != c3ptr &&
cli_serv(ac2ptr)->timestamp >
(c2ptr ? cli_serv(c2ptr)->timestamp : timestamp))
c2ptr = ac2ptr;
if (IsServer(sptr))
{
for (ac2ptr = sptr; ac2ptr != &me; ac2ptr = cli_serv(ac2ptr)->up)
if (ac2ptr != c3ptr &&
cli_serv(ac2ptr)->timestamp >
(c2ptr ? cli_serv(c2ptr)->timestamp : timestamp))
c2ptr = ac2ptr;
}
if (c3ptr && timestamp > (c2ptr ? cli_serv(c2ptr)->timestamp : timestamp))
c2ptr = 0;
/* If timestamps are equal, decide which link to break
* by name.
*/
if ((c2ptr ? cli_serv(c2ptr)->timestamp : timestamp) ==
(c3ptr ? cli_serv(c3ptr)->timestamp : timestamp))
{
char* n2;
char* n2up;
char* n3;
char* n3up;
if (c2ptr)
{
n2 = cli_name(c2ptr);
n2up = MyConnect(c2ptr) ? cli_name(&me) : cli_name(cli_serv(c2ptr)->up);
}
else
{
n2 = host;
n2up = IsServer(sptr) ? cli_name(sptr) : cli_name(&me);
}
if (c3ptr)
{
n3 = cli_name(c3ptr);
n3up = MyConnect(c3ptr) ? cli_name(&me) : cli_name(cli_serv(c3ptr)->up);
}
else
{
n3 = host;
n3up = IsServer(sptr) ? cli_name(sptr) : cli_name(&me);
}
if (strcmp(n2, n2up) > 0)
n2 = n2up;
if (strcmp(n3, n3up) > 0)
n3 = n3up;
if (strcmp(n3, n2) > 0)
{
ac2ptr = c2ptr;
c2ptr = c3ptr;
c3ptr = ac2ptr;
}
}
/* Now squit the second youngest link: */
if (!c2ptr)
return exit_new_server(cptr, sptr, host, timestamp,
"server %s already exists and is %ld seconds younger.",
host, (long)cli_serv(acptr)->timestamp - (long)timestamp);
else if (cli_from(c2ptr) == cptr || IsServer(sptr))
{
struct Client *killedptrfrom = cli_from(c2ptr);
if (active_lh_line)
{
/*
* If the L: or H: line also gets rid of this link,
* we sent just one squit.
*/
if (LHcptr && a_kills_b_too(LHcptr, c2ptr))
break;
/*
* If breaking the loop here solves the L: or H:
* line problem, we don't squit that.
*/
if (cli_from(c2ptr) == cptr || (LHcptr && a_kills_b_too(c2ptr, LHcptr)))
active_lh_line = 0;
else
{
/*
* If we still have a L: or H: line problem,
* we prefer to squit the new server, solving
* loop and L:/H: line problem with only one squit.
*/
LHcptr = 0;
break;
}
}
/*
* If the new server was introduced by a server that caused a
* Ghost less then 20 seconds ago, this is probably also
* a Ghost... (20 seconds is more then enough because all
* SERVER messages are at the beginning of a net.burst). --Run
*/
if (CurrentTime - cli_serv(cptr)->ghost < 20)
{
killedptrfrom = cli_from(acptr);
if (exit_client(cptr, acptr, &me, "Ghost loop") == CPTR_KILLED)
return CPTR_KILLED;
}
else if (exit_client_msg(cptr, c2ptr, &me,
"Loop <-- %s (new link is %ld seconds younger)", host,
(c3ptr ? (long)cli_serv(c3ptr)->timestamp : timestamp) -
(long)cli_serv(c2ptr)->timestamp) == CPTR_KILLED)
return CPTR_KILLED;
/*
* Did we kill the incoming server off already ?
*/
if (killedptrfrom == cptr)
return 0;
}
else
{
if (active_lh_line)
{
if (LHcptr && a_kills_b_too(LHcptr, acptr))
break;
if (cli_from(acptr) == cptr || (LHcptr && a_kills_b_too(acptr, LHcptr)))
active_lh_line = 0;
else
{
LHcptr = 0;
break;
}
}
/*
* We can't believe it is a lagged server message
* when it directly connects to us...
* kill the older link at the ghost, rather then
* at the second youngest link, assuming it isn't
* a REAL loop.
*/
ghost = CurrentTime; /* Mark that it caused a ghost */
if (exit_client(cptr, acptr, &me, "Ghost") == CPTR_KILLED)
return CPTR_KILLED;
break;
}
}
}
if (active_lh_line)
{
if (LHcptr == 0) {
return exit_new_server(cptr, sptr, host, timestamp,
(active_lh_line == 2) ? "Non-Hub link %s <- %s(%s)" : "Leaf-only link %s <- %s(%s)",
cli_name(cptr), host,
lhconf ? (lhconf->name ? lhconf->name : "*") : "!");
}
else
{
int killed = a_kills_b_too(LHcptr, sptr);
if (active_lh_line < 3)
{
if (exit_client_msg(cptr, LHcptr, &me,
(active_lh_line == 2) ? "Non-Hub link %s <- %s(%s)" : "Leaf-only link %s <- %s(%s)",
cli_name(cptr), host,
lhconf ? (lhconf->name ? lhconf->name : "*") : "!") == CPTR_KILLED)
return CPTR_KILLED;
}
else
{
ServerStats->is_ref++;
if (exit_client(cptr, LHcptr, &me, "I'm a leaf") == CPTR_KILLED)
return CPTR_KILLED;
}
/*
* Did we kill the incoming server off already ?
*/
if (killed)
return 0;
}
}
if (IsServer(cptr))
{
/*
* 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...
*/
acptr = make_client(cptr, STAT_SERVER);
make_server(acptr);
cli_serv(acptr)->prot = prot;
cli_serv(acptr)->timestamp = timestamp;
cli_hopcount(acptr) = hop;
if (is_hub)
SetFlag(acptr, FLAG_HUB);
if (is_service)
SetFlag(acptr, FLAG_SERVICE);
ircd_strncpy(cli_name(acptr), host, HOSTLEN);
ircd_strncpy(cli_info(acptr), info, REALLEN);
cli_serv(acptr)->up = sptr;
cli_serv(acptr)->updown = add_dlink(&(cli_serv(sptr))->down, acptr);
/* Use cptr, because we do protocol 9 -> 10 translation
for numeric nicks ! */
SetServerYXX(cptr, acptr, parv[6]);
Count_newremoteserver(UserStats);
if (Protocol(acptr) < 10)
SetFlag(acptr, FLAG_TS8);
add_client_to_list(acptr);
hAddClient(acptr);
map_update(acptr);
if (*parv[5] == 'J')
{
SetBurst(acptr);
sendto_opmask_butone(0, SNO_NETWORK, "Net junction: %s %s",
cli_name(sptr), cli_name(acptr));
SetJunction(acptr);
}
/*
* Old sendto_serv_but_one() call removed because we now need to send
* different names to different servers (domain name matching).
*/
for (i = 0; i <= HighestFd; i++)
{
if (!(bcptr = LocalClientArray[i]) || !IsServer(bcptr) ||
bcptr == cptr || IsMe(bcptr))
continue;
if (0 == match(cli_name(&me), cli_name(acptr)))
continue;
sendcmdto_one(sptr, CMD_SERVER, bcptr, "%s %d 0 %s %s %s%s +%s%s :%s",
cli_name(acptr), hop + 1, parv[4], parv[5],
NumServCap(acptr), IsHub(acptr) ? "h" : "",
IsService(acptr) ? "s" : "", cli_info(acptr));
}
return 0;
}
if (IsUnknown(cptr) || IsHandshake(cptr))
{
make_server(cptr);
cli_serv(cptr)->timestamp = timestamp;
cli_serv(cptr)->prot = prot;
cli_serv(cptr)->ghost = ghost;
SetServerYXX(cptr, cptr, parv[6]);
if (start_timestamp > OLDEST_TS)
{
Debug((DEBUG_DEBUG, "My start time: %Tu; other's start time: %Tu",
cli_serv(&me)->timestamp, start_timestamp));
Debug((DEBUG_DEBUG, "Receive time: %Tu; received timestamp: %Tu; "
"difference %ld", recv_time, timestamp, timestamp - recv_time));
if (feature_bool(FEAT_RELIABLE_CLOCK)) {
if (start_timestamp < cli_serv(&me)->timestamp)
cli_serv(&me)->timestamp = start_timestamp;
if (IsUnknown(cptr))
cli_serv(cptr)->timestamp = TStime();
} else {
if (start_timestamp < cli_serv(&me)->timestamp) {
sendto_opmask_butone(0, SNO_OLDSNO, "got earlier start time: "
"%Tu < %Tu", start_timestamp,
cli_serv(&me)->timestamp);
cli_serv(&me)->timestamp = start_timestamp;
TSoffset += timestamp - recv_time;
sendto_opmask_butone(0, SNO_OLDSNO, "clock adjusted by adding %d",
(int)(timestamp - recv_time));
} else if ((start_timestamp > cli_serv(&me)->timestamp) &&
IsUnknown(cptr))
cli_serv(cptr)->timestamp = TStime();
else if (timestamp != recv_time) {
/*
* Equal start times, we have a collision. Let the connected-to
* server decide. This assumes leafs issue more than half of the
* connection attempts.
*/
if (IsUnknown(cptr))
cli_serv(cptr)->timestamp = TStime();
else if (IsHandshake(cptr)) {
sendto_opmask_butone(0, SNO_OLDSNO, "clock adjusted by adding %d",
(int)(timestamp - recv_time));
TSoffset += timestamp - recv_time;
}
}
}
}
ret = server_estab(cptr, aconf);
}
else
ret = 0;
if (feature_bool(FEAT_RELIABLE_CLOCK) &&
abs(cli_serv(cptr)->timestamp - recv_time) > 30) {
sendto_opmask_butone(0, SNO_OLDSNO, "Connected to a net with a "
"timestamp-clock difference of %Td seconds! Used "
"SETTIME to correct this.", timestamp - recv_time);
sendcmdto_prio_one(&me, CMD_SETTIME, cptr, "%Tu :%s", TStime(),
cli_name(&me));
}
return ret;
}
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