/************************************************************************
* IRC - Internet Relay Chat, src/parse.c
* Copyright (C) 1990 Jarkko Oikarinen and
* University of Oulu, Computing Center
*
* 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: parse.c,v 1.4 2005/07/05 21:53:41 sheik Exp $ */
#include "struct.h"
#include "common.h"
#include "sys.h"
#include "numeric.h"
#include "h.h"
#define MSGTAB
#include "msg.h"
#undef MSGTAB
#include "memcount.h"
#if defined( HAVE_STRING_H )
#include <string.h>
#else
#include <strings.h>
#endif
/* NOTE: parse() should not be called recursively by other functions! */
static char *para[MAXPARA + 1];
static int cancel_clients(aClient *, aClient *, char *);
static void remove_unknown(aClient *, char *, char *);
static char sender[HOSTLEN + 1];
static int cancel_clients(aClient *, aClient *, char *);
static void remove_unknown(aClient *, char *, char *);
static struct Message *do_msg_tree(MESSAGE_TREE *, char *, struct Message *);
static struct Message *tree_parse(char *);
int num_msg_trees = 0;
/*
* parse a buffer.
*
* NOTE: parse() should not be called recusively by any other functions!
*/
int parse(aClient *cptr, char *buffer, char *bufend)
{
aClient *from = cptr;
char *ch, *s;
int i, numeric = 0, paramcount;
struct Message *mptr;
#ifdef DUMP_DEBUG
if(dumpfp!=NULL)
{
fprintf(dumpfp, "<- %s: %s\n", (cptr->name ? cptr->name : "*"),
buffer);
fflush(dumpfp);
}
#endif
Debug((DEBUG_DEBUG, "Parsing %s: %s", get_client_name(cptr, TRUE),
buffer));
if (IsDead(cptr))
return -1;
s = sender;
*s = '\0';
for (ch = buffer; *ch == ' '; ch++); /* skip spaces */
para[0] = from->name;
if (*ch == ':')
{
/*
* Copy the prefix to 'sender' assuming it terminates with
* SPACE (or NULL, which is an error, though).
*/
for (++ch; *ch && *ch != ' '; ++ch)
if (s < (sender + HOSTLEN))
*s++ = *ch;
*s = '\0';
/*
* Actually, only messages coming from servers can have the
* prefix--prefix silently ignored, if coming from a user
* client...
*
* ...sigh, the current release "v2.2PL1" generates also null
* prefixes, at least to NOTIFY messages (e.g. it puts
* "sptr->nickname" as prefix from server structures where it's
* null--the following will handle this case as "no prefix" at
* all --msa (": NOTICE nick ...")
*/
if (*sender && IsServer(cptr))
{
from = find_client(sender, (aClient *) NULL);
/*
* okay, this doesn't seem to do much here.
* from->name _MUST_ be equal to sender.
* That's what find_client does.
* find_client will find servers too, and since we don't use server
* masking, the find server call is useless (and very wasteful).
* now, there HAS to be a from and from->name and
* sender have to be the same
* for us to get to the next if. but the next if
* starts out with if(!from)
* so this is UNREACHABLE CODE! AGH! - lucas
*
* if (!from || mycmp(from->name, sender))
* from = find_server(sender, (aClient *) NULL);
* else if (!from && strchr(sender, '@'))
* from = find_nickserv(sender, (aClient *) NULL);
*/
para[0] = sender;
/*
* Hmm! If the client corresponding to the prefix is not
* found--what is the correct action??? Now, I will ignore the
* message (old IRC just let it through as if the prefix just
* wasn't there...) --msa
*/
if (!from)
{
Debug((DEBUG_ERROR, "Unknown prefix (%s)(%s) from (%s)",
sender, buffer, cptr->name));
ircstp->is_unpf++;
remove_unknown(cptr, sender, buffer);
return -1;
}
if (from->from != cptr)
{
ircstp->is_wrdi++;
Debug((DEBUG_ERROR, "Message (%s) coming from (%s)",
buffer, cptr->name));
return cancel_clients(cptr, from, buffer);
}
}
while (*ch == ' ')
ch++;
}
if (*ch == '\0')
{
ircstp->is_empt++;
Debug((DEBUG_NOTICE, "Empty message from host %s:%s",
cptr->name, from->name));
return (-1);
}
/*
* Extract the command code from the packet. Point s to the end
* of the command code and calculate the length using pointer
* arithmetic. Note: only need length for numerics and *all*
* numerics must have parameters and thus a space after the command
* code. -avalon
*
* ummm???? - Dianora
*/
/* Reparse point for /msg raw - Tux` */
reparse:
/* check for numeric */
if (*(ch + 3) == ' ' && IsDigit(*ch) && IsDigit(*(ch + 1)) &&
IsDigit(*(ch + 2)))
{
mptr = (struct Message *) NULL;
numeric = (*ch - '0') * 100 + (*(ch + 1) - '0') *
10 + (*(ch + 2) - '0');
paramcount = MAXPARA;
ircstp->is_num++;
s = ch + 3;
*s++ = '\0';
}
else
{
s = strchr(ch, ' ');
if (s)
*s++ = '\0';
mptr = tree_parse(ch);
if ((mptr && mptr->func == m_private) &&
(s && !strncasecmp(s, "raw ", 4)))
{
ch = index(s, ':');
if (ch++)
goto reparse;
}
else if (!mptr || !mptr->cmd)
{
/*
* only send error messages to things that actually sent
* buffers to us and only people, too.
*/
if (buffer[0] != '\0')
{
if (IsPerson(from))
sendto_one(from, ":%s %d %s %s :Unknown command",
me.name, ERR_UNKNOWNCOMMAND, from->name, ch);
Debug((DEBUG_ERROR, "Unknown (%s) from %s",
ch, get_client_name(cptr, TRUE)));
}
ircstp->is_unco++;
return -1;
}
paramcount = mptr->parameters;
i = bufend - ((s) ? s : ch);
mptr->bytes += i;
/*
* Allow only 1 msg per 2 seconds (on average) to prevent
* dumping. to keep the response rate up, bursts of up to 5 msgs
* are allowed -SRB Opers can send 1 msg per second, burst of ~20
* -Taner
*/
if (!IsServer(cptr))
{
if (!NoMsgThrottle(cptr))
{
#ifdef NO_OPER_FLOOD
if (IsAnOper(cptr))
/* "randomly" (weighted) increase the since */
cptr->since += (cptr->receiveM % 10) ? 1 : 0;
else
#endif
cptr->since += (2 + i / 120);
}
}
}
/*
* Must the following loop really be so devious? On surface it
* splits the message to parameters from blank spaces. But, if
* paramcount has been reached, the rest of the message goes into
* this last parameter (about same effect as ":" has...) --msa
*/
/* Note initially true: s==NULL || *(s-1) == '\0' !! */
i = 1;
if (s)
{
if (paramcount > MAXPARA)
paramcount = MAXPARA;
for (;;)
{
while (*s == ' ')
*s++ = '\0';
if (*s == '\0')
break;
if (*s == ':')
{
/* The rest is a single parameter */
para[i++] = s + 1;
break;
}
para[i++] = s;
if (i >= paramcount)
{
if(paramcount == MAXPARA && strchr(s, ' '))
{
sendto_realops_lev(DEBUG_LEV, "Overflowed MAXPARA on %s from %s",
mptr ? mptr->cmd : "numeric",
get_client_name(cptr, (IsServer(cptr) ? HIDEME : FALSE)));
}
break;
}
while(*s && *s != ' ')
s++;
}
}
para[i] = NULL;
if (mptr == (struct Message *) NULL)
return (do_numeric(numeric, cptr, from, i, para));
mptr->count++;
/* patch to avoid server flooding from unregistered connects */
if (!IsRegistered(cptr) && !(mptr->flags & MF_UNREG)) {
sendto_one(from, ":%s %d %s %s :Register first.",
me.name, ERR_NOTREGISTERED, from->name, ch);
return -1;
}
if (IsRegisteredUser(cptr) && (mptr->flags & MF_RIDLE))
from->user->last = timeofday;
if (mptr->flags & MF_ALIAS)
return mptr->func(cptr, from, i, para, &aliastab[mptr->aliasidx]);
return (*mptr->func) (cptr, from, i, para);
}
/*
* init_tree_parse()
*
* inputs - pointer to msg_table defined in msg.h output
* NONE side effects - MUST MUST be called at startup ONCE before
* any other keyword hash routine is used.
*
* -Dianora, orabidoo
*/
/* for qsort'ing the msgtab in place -orabidoo */
static int mcmp(struct Message *m1, struct Message *m2)
{
return strcmp(m1->cmd, m2->cmd);
}
/* Initialize the msgtab parsing tree -orabidoo */
void init_tree_parse(struct Message *mptr)
{
int i;
struct Message *mpt = mptr;
for (i = 0; mpt->cmd; mpt++)
i++;
qsort((void *) mptr, i, sizeof(struct Message),
(int (*)(const void *, const void *)) mcmp);
msg_tree_root = (MESSAGE_TREE *) MyMalloc(sizeof(MESSAGE_TREE));
num_msg_trees++;
mpt = do_msg_tree(msg_tree_root, "", mptr);
/*
* this happens if one of the msgtab entries included characters
* other than capital letters -orabidoo
*/
if (mpt->cmd)
{
fprintf(stderr, "bad msgtab entry: ``%s''\n", mpt->cmd);
exit(1);
}
}
/* Recursively make a prefix tree out of the msgtab -orabidoo */
static struct Message *do_msg_tree(MESSAGE_TREE * mtree, char *prefix,
struct Message *mptr)
{
char newpref[64]; /* must be longer than any command */
int c, c2, lp;
MESSAGE_TREE *mtree1;
lp = strlen(prefix);
if (!lp || !strncmp(mptr->cmd, prefix, lp))
{
if (!mptr[1].cmd || (lp && strncmp(mptr[1].cmd, prefix, lp)))
{
/* non ambiguous, make a final case */
mtree->final = mptr->cmd + lp;
mtree->msg = mptr;
for (c = 0; c <= 25; c++)
mtree->pointers[c] = NULL;
return mptr + 1;
}
else
{
/* ambigous, make new entries for each of the letters that match */
if (!mycmp(mptr->cmd, prefix))
{
mtree->final = (void *) 1;
mtree->msg = mptr;
mptr++;
}
else
mtree->final = NULL;
for (c = 'A'; c <= 'Z'; c++)
{
if (mptr->cmd[lp] == c)
{
mtree1 = (MESSAGE_TREE *) MyMalloc(sizeof(MESSAGE_TREE));
num_msg_trees++;
mtree1->final = NULL;
mtree->pointers[c - 'A'] = mtree1;
strcpy(newpref, prefix);
newpref[lp] = c;
newpref[lp + 1] = '\0';
mptr = do_msg_tree(mtree1, newpref, mptr);
if (!mptr->cmd || strncmp(mptr->cmd, prefix, lp))
{
for (c2 = c + 1 - 'A'; c2 <= 25; c2++)
mtree->pointers[c2] = NULL;
return mptr;
}
}
else
{
mtree->pointers[c - 'A'] = NULL;
}
}
return mptr;
}
}
else
{
fprintf(stderr, "do_msg_tree: this should never happen!\n");
exit(1);
}
}
/*
* tree_parse()
*
* inputs
* - pointer to command in upper case output NULL pointer if not found
* struct Message pointer to command entry if found
* side effects - NONE
*
* -Dianora, orabidoo
*/
static struct Message *tree_parse(char *cmd)
{
char r;
MESSAGE_TREE *mtree = msg_tree_root;
while ((r = *cmd++))
{
r &= 0xdf; /*
* some touppers have trouble w/
* lowercase, says Dianora
*/
if (r < 'A' || r > 'Z')
return NULL;
mtree = mtree->pointers[r - 'A'];
if (!mtree)
return NULL;
if (mtree->final == (void *) 1)
{
if (!*cmd)
return mtree->msg;
}
else if (mtree->final && !mycmp(mtree->final, cmd))
return mtree->msg;
}
return ((struct Message *) NULL);
}
/* field breakup for ircd.conf file. */
char *getfield(char *newline)
{
static char *line = (char *) NULL;
char *end, *field;
if (newline)
line = newline;
if (line == (char *) NULL)
return ((char *) NULL);
field = line;
if ((end = strchr(line, ':')) == NULL)
{
line = (char *) NULL;
if ((end = strchr(field, '\n')) == (char *) NULL)
end = field + strlen(field);
}
else
line = end + 1;
*end = '\0';
return (field);
}
static int cancel_clients(aClient *cptr, aClient *sptr, char *cmd)
{
/*
* kill all possible points that are causing confusion here, I'm not
* sure I've got this all right... - avalon
*
* knowing avalon, probably not.
*/
/*
* with TS, fake prefixes are a common thing, during the connect
* burst when there's a nick collision, and they must be ignored
* rather than killed because one of the two is surviving.. so we
* don't bother sending them to all ops everytime, as this could
* send 'private' stuff from lagged clients. we do send the ones
* that cause servers to be dropped though, as well as the ones
* from * non-TS servers -orabidoo
*/
/*
* Incorrect prefix for a server from some connection. If it is a
* client trying to be annoying, just QUIT them, if it is a server
* then the same deal.
*/
if (IsServer(sptr) || IsMe(sptr))
{
/* Sorry, but at the moment this is just too much for even opers
to see. -Rak */
/* or we could just take out the message. <EG> -wd */
sendto_realops_lev(DEBUG_LEV, "Message for %s[%s] from %s",
sptr->name, sptr->from->name,
get_client_name(cptr,
(IsServer(cptr) ? HIDEME : FALSE)));
if (IsServer(cptr))
{
sendto_realops_lev(DEBUG_LEV,
"Not dropping server %s (%s) for "
"Fake Direction", cptr->name, sptr->name);
return -1;
}
if (IsClient(cptr))
sendto_realops_lev(DEBUG_LEV,
"Would have dropped client %s (%s@%s) "
"[%s from %s]", cptr->name,
cptr->user->username, cptr->user->host,
cptr->user->server, cptr->from->name);
return -1;
}
/*
* Ok, someone is trying to impose as a client and things are
* confused. If we got the wrong prefix from a server, send out a
* kill, else just exit the lame client.
*/
if (IsServer(cptr))
{
/*
* If the fake prefix is coming from a TS server, discard it
* silently -orabidoo
* also drop it if we're gonna kill services by not doing so }:/
*/
if (DoesTS(cptr))
{
if (sptr->user)
sendto_realops_lev(DEBUG_LEV,
"Message for %s[%s@%s!%s] from %s "
"(TS, ignored)", sptr->name,
sptr->user->username, sptr->user->host,
sptr->from->name,
get_client_name(cptr, HIDEME));
return 0;
}
else
{
if (sptr->user)
sendto_realops_lev(DEBUG_LEV,
"Message for %s[%s@%s!%s] from %s",
sptr->name, sptr->user->username,
sptr->user->host,
sptr->from->name,
get_client_name(cptr, HIDEME));
if(IsULine(sptr))
{
sendto_realops_lev(DEBUG_LEV,
"Would have killed U:lined client %s "
"for fake direction", sptr->name);
return 0;
}
sendto_serv_butone(NULL,
":%s KILL %s :%s (%s[%s] != %s, Fake Prefix)",
me.name, sptr->name, me.name,
sptr->name, sptr->from->name,
get_client_name(cptr, HIDEME));
sptr->flags |= FLAGS_KILLED;
return exit_client(cptr, sptr, &me, "Fake Prefix");
}
}
return exit_client(cptr, cptr, &me, "Fake prefix");
}
static void remove_unknown(aClient *cptr, char *sender, char *buffer)
{
if (!IsRegistered(cptr))
return;
if (IsClient(cptr))
{
sendto_realops_lev(DEBUG_LEV,
"Weirdness: Unknown client prefix (%s) from %s, "
"Ignoring %s", buffer,
get_client_name(cptr, FALSE), sender);
return;
}
/* Not from a server so don't need to worry about it. */
if (!IsServer(cptr))
return;
/*
* Do kill if it came from a server because it means there is a
* ghost user on the other server which needs to be removed. -avalon
* Tell opers about this. -Taner
*/
if (!strchr(sender, '.'))
sendto_one(cptr, ":%s KILL %s :%s (%s(?) <- %s)",
me.name, sender, me.name, sender,
get_client_name(cptr, FALSE));
else
{
sendto_realops_lev(DEBUG_LEV,
"Unknown prefix (%s) from %s, Squitting %s",
buffer, get_client_name(cptr, HIDEME), sender);
sendto_one(cptr, ":%s SQUIT %s :(Unknown prefix (%s) from %s)",
me.name, sender, buffer, get_client_name(cptr, HIDEME));
}
}
static u_long
r_msgtree_memcount(MESSAGE_TREE *mptr, int *count)
{
int i;
u_long m = sizeof(*mptr);
(*count)++;
for (i = 0; i < sizeof(mptr->pointers)/sizeof(mptr->pointers[0]); i++)
if (mptr->pointers[i])
m += r_msgtree_memcount(mptr->pointers[i], count);
return m;
}
u_long
memcount_parse(MCparse *mc)
{
mc->file = __FILE__;
mc->msgnodes.m = r_msgtree_memcount(msg_tree_root, &mc->msgnodes.c);
mc->total.c += mc->msgnodes.c;
mc->total.m += mc->msgnodes.m;
mc->s_bufs.c++;
mc->s_bufs.m += sizeof(para);
mc->s_bufs.c++;
mc->s_bufs.m += sizeof(sender);
mc->s_msgtab.c = sizeof(msgtab)/sizeof(msgtab[0]);
mc->s_msgtab.m = sizeof(msgtab);
return mc->total.m;
}
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