solanum-vs-hackint-and-char.../ircd/parse.c

653 lines
16 KiB
C

/*
* charybdis: an advanced ircd.
* parse.c: The message parser.
*
* 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
* Copyright (C) 2007-2016 William Pitcock
*
* 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: parse.c 3177 2007-02-01 00:19:14Z jilles $
*/
#include "stdinc.h"
#include "parse.h"
#include "client.h"
#include "channel.h"
#include "common.h"
#include "hash.h"
#include "match.h"
#include "ircd.h"
#include "numeric.h"
#include "logger.h"
#include "s_stats.h"
#include "send.h"
#include "msg.h"
#include "msgbuf.h"
#include "s_conf.h"
#include "s_serv.h"
#include "packet.h"
#include "s_assert.h"
static struct Dictionary *cmd_dict = NULL;
struct Dictionary *alias_dict = NULL;
/* parv[0] is not used, and parv[LAST] == NULL */
static char *para[MAXPARA + 2];
static void cancel_clients(struct Client *, struct Client *);
static void remove_unknown(struct Client *, const char *, char *);
static void do_numeric(int, struct Client *, struct Client *, int, const char **);
static void do_alias(struct alias_entry *, struct Client *, char *);
static int handle_command(struct Message *, struct MsgBuf *, struct Client *, struct Client *);
static char buffer[1024];
/* turn a string into a parc/parv pair */
char *reconstruct_parv(int parc, const char *parv[])
{
static char tmpbuf[BUFSIZE]; int i;
rb_strlcpy(tmpbuf, parv[0], BUFSIZE);
for (i = 1; i < parc; i++)
{
rb_strlcat(tmpbuf, " ", BUFSIZE);
rb_strlcat(tmpbuf, parv[i], BUFSIZE);
}
return tmpbuf;
}
/* parse()
*
* given a raw buffer, parses it and generates parv and parc
*/
void
parse(struct Client *client_p, char *pbuffer, char *bufend)
{
struct Client *from = client_p;
char *end;
int i = 1, res;
int numeric = 0;
struct Message *mptr;
struct MsgBuf msgbuf;
s_assert(MyConnect(client_p));
s_assert(client_p->localClient->F != NULL);
if(IsAnyDead(client_p))
return;
end = bufend - 1;
/* XXX this should be done before parse() is called */
if(*end == '\n')
*end-- = '\0';
if(*end == '\r')
*end = '\0';
res = msgbuf_parse(&msgbuf, pbuffer);
if (res)
{
ServerStats.is_empt++;
return;
}
if (msgbuf.origin != NULL)
{
from = find_client(msgbuf.origin);
/* didnt find any matching client, issue a kill */
if(from == NULL)
{
ServerStats.is_unpf++;
remove_unknown(client_p, msgbuf.origin, pbuffer);
return;
}
/* fake direction, hmm. */
if(from->from != client_p)
{
ServerStats.is_wrdi++;
cancel_clients(client_p, from);
return;
}
}
if(IsDigit(*msgbuf.cmd) && IsDigit(*(msgbuf.cmd + 1)) && IsDigit(*(msgbuf.cmd + 2)))
{
mptr = NULL;
numeric = atoi(msgbuf.cmd);
ServerStats.is_num++;
}
else
{
mptr = irc_dictionary_retrieve(cmd_dict, msgbuf.cmd);
/* no command or its encap only, error */
if(!mptr || !mptr->cmd)
{
if (IsPerson(client_p))
{
struct alias_entry *aptr = irc_dictionary_retrieve(alias_dict, msgbuf.cmd);
if (aptr != NULL)
{
do_alias(aptr, client_p, reconstruct_parv(msgbuf.n_para - 1, msgbuf.para + 1));
return;
}
}
if(IsPerson(from))
{
sendto_one(from, form_str(ERR_UNKNOWNCOMMAND),
me.name, from->name, msgbuf.cmd);
}
ServerStats.is_unco++;
return;
}
mptr->bytes += msgbuf.parselen;
}
if(mptr == NULL)
{
do_numeric(numeric, client_p, from, msgbuf.n_para, msgbuf.para);
return;
}
if(handle_command(mptr, &msgbuf, client_p, from) < -1)
{
char *p;
for (p = pbuffer; p <= end; p += 8)
{
/* HACK HACK */
/* Its expected this nasty code can be removed
* or rewritten later if still needed.
*/
if((unsigned long) (p + 8) > (unsigned long) end)
{
for (; p <= end; p++)
{
ilog(L_MAIN, "%02x |%c", p[0], p[0]);
}
}
else
ilog(L_MAIN,
"%02x %02x %02x %02x %02x %02x %02x %02x |%c%c%c%c%c%c%c%c",
p[0], p[1], p[2], p[3], p[4], p[5],
p[6], p[7], p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7]);
}
}
}
/*
* handle_command
*
* inputs - pointer to message block
* - pointer to message buffer
* - pointer to client
* - pointer to client message is from
* output - -1 if error from server
* side effects -
*/
static int
handle_command(struct Message *mptr, struct MsgBuf *msgbuf_p, struct Client *client_p, struct Client *from)
{
struct MessageEntry ehandler;
MessageHandler handler = 0;
char squitreason[80];
if(IsAnyDead(client_p))
return -1;
if(IsServer(client_p))
mptr->rcount++;
mptr->count++;
/* New patch to avoid server flooding from unregistered connects
- Pie-Man 07/27/2000 */
if(!IsRegistered(client_p))
{
/* if its from a possible server connection
* ignore it.. more than likely its a header thats sneaked through
*/
if(IsAnyServer(client_p) && !(mptr->flags & MFLG_UNREG))
return (1);
}
ehandler = mptr->handlers[from->handler];
handler = ehandler.handler;
/* check right amount of params is passed... --is */
if(msgbuf_p->n_para < ehandler.min_para ||
(ehandler.min_para && EmptyString(msgbuf_p->para[ehandler.min_para - 1])))
{
if(!IsServer(client_p))
{
sendto_one(client_p, form_str(ERR_NEEDMOREPARAMS),
me.name,
EmptyString(client_p->name) ? "*" : client_p->name,
mptr->cmd);
if(MyClient(client_p))
return (1);
else
return (-1);
}
sendto_realops_snomask(SNO_GENERAL, L_ALL,
"Dropping server %s due to (invalid) command '%s'"
" with only %zu arguments (expecting %d).",
client_p->name, mptr->cmd, msgbuf_p->n_para, ehandler.min_para);
ilog(L_SERVER,
"Insufficient parameters (%zu < %d) for command '%s' from %s.",
msgbuf_p->n_para, ehandler.min_para, mptr->cmd, client_p->name);
snprintf(squitreason, sizeof squitreason,
"Insufficient parameters (%zu < %d) for command '%s'",
msgbuf_p->n_para, ehandler.min_para, mptr->cmd);
exit_client(client_p, client_p, client_p, squitreason);
return (-1);
}
(*handler) (msgbuf_p, client_p, from, msgbuf_p->n_para, msgbuf_p->para);
return (1);
}
void
handle_encap(struct MsgBuf *msgbuf_p, struct Client *client_p, struct Client *source_p,
const char *command, int parc, const char *parv[])
{
struct Message *mptr;
struct MessageEntry ehandler;
MessageHandler handler = 0;
mptr = irc_dictionary_retrieve(cmd_dict, command);
if(mptr == NULL || mptr->cmd == NULL)
return;
ehandler = mptr->handlers[ENCAP_HANDLER];
handler = ehandler.handler;
if(parc < ehandler.min_para ||
(ehandler.min_para && EmptyString(parv[ehandler.min_para - 1])))
return;
(*handler) (msgbuf_p, client_p, source_p, parc, parv);
}
/*
* clear_hash_parse()
*
* inputs -
* output - NONE
* side effects - MUST MUST be called at startup ONCE before
* any other keyword hash routine is used.
*
*/
void
clear_hash_parse()
{
cmd_dict = irc_dictionary_create("command", strcasecmp);
}
/* mod_add_cmd
*
* inputs - command name
* - pointer to struct Message
* output - none
* side effects - load this one command name
* msg->count msg->bytes is modified in place, in
* modules address space. Might not want to do that...
*/
void
mod_add_cmd(struct Message *msg)
{
s_assert(msg != NULL);
if(msg == NULL)
return;
if (irc_dictionary_find(cmd_dict, msg->cmd) != NULL)
return;
msg->count = 0;
msg->rcount = 0;
msg->bytes = 0;
irc_dictionary_add(cmd_dict, msg->cmd, msg);
}
/* mod_del_cmd
*
* inputs - command name
* output - none
* side effects - unload this one command name
*/
void
mod_del_cmd(struct Message *msg)
{
s_assert(msg != NULL);
if(msg == NULL)
return;
irc_dictionary_delete(cmd_dict, msg->cmd);
}
/*
* report_messages
*
* inputs - pointer to client to report to
* output - NONE
* side effects - NONE
*/
void
report_messages(struct Client *source_p)
{
struct DictionaryIter iter;
struct Message *msg;
struct alias_entry *amsg;
DICTIONARY_FOREACH(msg, &iter, cmd_dict)
{
s_assert(msg->cmd != NULL);
sendto_one_numeric(source_p, RPL_STATSCOMMANDS,
form_str(RPL_STATSCOMMANDS),
msg->cmd, msg->count,
msg->bytes, msg->rcount);
}
DICTIONARY_FOREACH(amsg, &iter, alias_dict)
{
s_assert(amsg->name != NULL);
sendto_one_numeric(source_p, RPL_STATSCOMMANDS,
form_str(RPL_STATSCOMMANDS),
amsg->name, amsg->hits, 0L, 0);
}
}
/* cancel_clients()
*
* inputs - client who sent us the message, client with fake
* direction
* outputs - a given warning about the fake direction
* side effects -
*/
static void
cancel_clients(struct Client *client_p, struct Client *source_p)
{
/* ok, fake prefix happens naturally during a burst on a nick
* collision with TS5, we cant kill them because one client has to
* survive, so we just send an error.
*/
if(IsServer(source_p) || IsMe(source_p))
{
sendto_realops_snomask(SNO_DEBUG, L_ALL,
"Message for %s[%s] from %s",
source_p->name, source_p->from->name,
client_p->name);
}
else
{
sendto_realops_snomask(SNO_DEBUG, L_ALL,
"Message for %s[%s@%s!%s] from %s (TS, ignored)",
source_p->name,
source_p->username,
source_p->host,
source_p->from->name,
client_p->name);
}
}
/* remove_unknown()
*
* inputs - client who gave us message, supposed sender, buffer
* output -
* side effects - kills issued for clients, squits for servers
*/
static void
remove_unknown(struct Client *client_p, const char *lsender, char *lbuffer)
{
int slen = strlen(lsender);
char sid[4];
struct Client *server;
/* meepfoo is a nickname (ignore)
* #XXXXXXXX is a UID (KILL)
* #XX is a SID (SQUIT)
* meep.foo is a server (SQUIT)
*/
if((IsDigit(lsender[0]) && slen == 3) ||
(strchr(lsender, '.') != NULL))
{
sendto_realops_snomask(SNO_DEBUG, L_ALL,
"Unknown prefix (%s) from %s, Squitting %s",
lbuffer, client_p->name, lsender);
sendto_one(client_p,
":%s SQUIT %s :(Unknown prefix (%s) from %s)",
get_id(&me, client_p), lsender,
lbuffer, client_p->name);
}
else if(!IsDigit(lsender[0]))
;
else if(slen != 9)
sendto_realops_snomask(SNO_DEBUG, L_ALL,
"Invalid prefix (%s) from %s",
lbuffer, client_p->name);
else
{
memcpy(sid, lsender, 3);
sid[3] = '\0';
server = find_server(NULL, sid);
if (server != NULL && server->from == client_p)
sendto_one(client_p, ":%s KILL %s :%s (Unknown Client)",
get_id(&me, client_p), lsender, me.name);
}
}
/*
*
* parc number of arguments ('sender' counted as one!)
* parv[1]..parv[parc-1]
* pointers to additional parameters, this is a NULL
* terminated list (parv[parc] == NULL).
*
* *WARNING*
* Numerics are mostly error reports. If there is something
* wrong with the message, just *DROP* it! Don't even think of
* sending back a neat error message -- big danger of creating
* a ping pong error message...
*/
static void
do_numeric(int numeric, struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
{
struct Client *target_p;
struct Channel *chptr;
if(parc < 2 || !IsServer(source_p))
return;
/* Remap low number numerics. */
if(numeric < 100)
numeric += 100;
/*
* Prepare the parameter portion of the message into 'buffer'.
* (Because the buffer is twice as large as the message buffer
* for the socket, no overflow can occur here... ...on current
* assumptions--bets are off, if these are changed --msa)
* Note: if buffer is non-empty, it will begin with SPACE.
*/
if(parc > 1)
{
char *t = buffer; /* Current position within the buffer */
int i;
int tl; /* current length of presently being built string in t */
for (i = 2; i < (parc - 1); i++)
{
tl = sprintf(t, " %s", parv[i]);
t += tl;
}
sprintf(t, " :%s", parv[parc - 1]);
}
if((target_p = find_client(parv[1])) != NULL)
{
if(IsMe(target_p))
{
/*
* We shouldn't get numerics sent to us,
* any numerics we do get indicate a bug somewhere..
*/
/* ugh. this is here because of nick collisions. when two servers
* relink, they burst each other their nicks, then perform collides.
* if there is a nick collision, BOTH servers will kill their own
* nicks, and BOTH will kill the other servers nick, which wont exist,
* because it will have been already killed by the local server.
*
* unfortunately, as we cant guarantee other servers will do the
* "right thing" on a nick collision, we have to keep both kills.
* ergo we need to ignore ERR_NOSUCHNICK. --fl_
*/
/* quick comment. This _was_ tried. i.e. assume the other servers
* will do the "right thing" and kill a nick that is colliding.
* unfortunately, it did not work. --Dianora
*/
/* note, now we send PING on server connect, we can
* also get ERR_NOSUCHSERVER..
*/
if(numeric != ERR_NOSUCHNICK &&
numeric != ERR_NOSUCHSERVER)
sendto_realops_snomask(SNO_GENERAL, L_ADMIN,
"*** %s(via %s) sent a %03d numeric to me: %s",
source_p->name,
client_p->name, numeric, buffer);
return;
}
else if(target_p->from == client_p)
{
/* This message changed direction (nick collision?)
* ignore it.
*/
return;
}
/* csircd will send out unknown umode flag for +a (admin), drop it here. */
if(numeric == ERR_UMODEUNKNOWNFLAG && MyClient(target_p))
return;
/* Fake it for server hiding, if its our client */
sendto_one(target_p, ":%s %03d %s%s",
get_id(source_p, target_p), numeric,
get_id(target_p, target_p), buffer);
return;
}
else if((chptr = find_channel(parv[1])) != NULL)
sendto_channel_flags(client_p, ALL_MEMBERS, source_p, chptr,
"%03d %s%s",
numeric, chptr->chname, buffer);
}
static void do_alias(struct alias_entry *aptr, struct Client *source_p, char *text)
{
char *p;
struct Client *target_p;
if (!IsFloodDone(source_p) && source_p->localClient->receiveM > 20)
flood_endgrace(source_p);
p = strchr(aptr->target, '@');
if (p != NULL)
{
/* user@server */
target_p = find_server(NULL, p + 1);
if (target_p != NULL && IsMe(target_p))
target_p = NULL;
}
else
{
/* nick, must be +S */
target_p = find_named_person(aptr->target);
if (target_p != NULL && !IsService(target_p))
target_p = NULL;
}
if (target_p == NULL)
{
sendto_one_numeric(source_p, ERR_SERVICESDOWN, form_str(ERR_SERVICESDOWN), aptr->target);
return;
}
if (text != NULL && *text == ':')
text++;
if (text == NULL || *text == '\0')
{
sendto_one(source_p, form_str(ERR_NOTEXTTOSEND), me.name, source_p->name);
return;
}
/* increment the hitcounter on this alias */
aptr->hits++;
sendto_one(target_p, ":%s PRIVMSG %s :%s",
get_id(source_p, target_p),
p != NULL ? aptr->target : get_id(target_p, target_p),
text);
}
int
m_not_oper(struct MsgBuf *msgbuf_p, struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
{
sendto_one_numeric(source_p, ERR_NOPRIVILEGES, form_str(ERR_NOPRIVILEGES));
return 0;
}
int
m_unregistered(struct MsgBuf *msgbuf_p, struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
{
/* bit of a hack.
* I don't =really= want to waste a bit in a flag
* number_of_nick_changes is only really valid after the client
* is fully registered..
*/
if(client_p->localClient->number_of_nick_changes == 0)
{
sendto_one(client_p, form_str(ERR_NOTREGISTERED), me.name);
client_p->localClient->number_of_nick_changes++;
}
return 0;
}
int
m_registered(struct MsgBuf *msgbuf_p, struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
{
sendto_one(client_p, form_str(ERR_ALREADYREGISTRED), me.name, source_p->name);
return 0;
}
int
m_ignore(struct MsgBuf *msgbuf_p, struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
{
return 0;
}