2 * Copyright (C) 2000-2003 Darren Reed
4 * See the IPFILTER.LICENCE file for details on licencing.
6 * $Id: ip_irc_pxy.c,v 2.39.2.6 2006/07/14 06:12:14 darrenr Exp $
11 #define IPF_IRCBUFSZ 96 /* This *MUST* be >= 64! */
14 int ippr_irc_init __P((void));
15 void ippr_irc_fini __P((void));
16 int ippr_irc_new __P((fr_info_t *, ap_session_t *, nat_t *));
17 int ippr_irc_out __P((fr_info_t *, ap_session_t *, nat_t *));
18 int ippr_irc_send __P((fr_info_t *, nat_t *));
19 int ippr_irc_complete __P((ircinfo_t *, char *, size_t));
20 u_short ipf_irc_atoi __P((char **));
22 static frentry_t ircnatfr;
24 int irc_proxy_init = 0;
28 * Initialize local structures.
32 bzero((char *)&ircnatfr, sizeof(ircnatfr));
34 ircnatfr.fr_flags = FR_INQUE|FR_PASS|FR_QUICK|FR_KEEPSTATE;
35 MUTEX_INIT(&ircnatfr.fr_lock, "IRC proxy rule lock");
44 if (irc_proxy_init == 1) {
45 MUTEX_DESTROY(&ircnatfr.fr_lock);
51 const char *ippr_irc_dcctypes[] = {
52 "CHAT ", /* CHAT chat ipnumber portnumber */
53 "SEND ", /* SEND filename ipnumber portnumber */
62 * :A PRIVMSG B :^ADCC CHAT chat 0 0^A\r\n
63 * PRIVMSG B ^ADCC CHAT chat 0 0^A\r\n
67 int ippr_irc_complete(ircp, buf, len)
86 if ((c != ':') && (c != 'P'))
91 * Loosely check that the source is a nickname of some sort
99 for (c = *s; !ISSPACE(c) && (i > 0); i--)
106 ircp->irc_snick = NULL;
109 * Check command string
111 if (strncmp(s, "PRIVMSG ", 8))
119 * Loosely check that the destination is a nickname of some sort
123 for (; !ISSPACE(c) && (i > 0); i--)
131 * Look for a ^A to start the DCC
139 if (strncmp(s, "\001DCC ", 4))
146 * Check for a recognised DCC command
148 for (j = 0, k = 0; ippr_irc_dcctypes[j]; j++) {
149 k = MIN(strlen(ippr_irc_dcctypes[j]), i);
150 if (!strncmp(ippr_irc_dcctypes[j], s, k))
153 if (!ippr_irc_dcctypes[j])
170 for (; (c != ' ') && (c != '\001') && (i > 0); i--)
173 if (c == '\001') /* In reality a ^A can quote another ^A...*/
188 for (l = 0; ISDIGIT(c) && (i > 0); i--) {
209 for (l = 0; ISDIGIT(c) && (i > 0); i--) {
216 if (strncmp(s, "\001\r\n", 3))
219 ircp->irc_len = s - buf;
225 int ippr_irc_new(fin, aps, nat)
232 KMALLOC(irc, ircinfo_t *);
236 fin = fin; /* LINT */
237 nat = nat; /* LINT */
240 aps->aps_psiz = sizeof(ircinfo_t);
242 bzero((char *)irc, sizeof(*irc));
247 int ippr_irc_send(fin, nat)
251 char ctcpbuf[IPF_IRCBUFSZ], newbuf[IPF_IRCBUFSZ];
252 tcphdr_t *tcp, tcph, *tcp2 = &tcph;
253 int off, inc = 0, i, dlen;
254 size_t nlen = 0, olen;
269 tcp = (tcphdr_t *)fin->fin_dp;
270 bzero(ctcpbuf, sizeof(ctcpbuf));
271 off = (char *)tcp - (char *)ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff;
274 dlen = fin->fin_plen - off;
276 dlen = MSGDSIZE(m) - off;
280 COPYDATA(m, off, MIN(sizeof(ctcpbuf), dlen), ctcpbuf);
284 ctcpbuf[sizeof(ctcpbuf) - 1] = '\0';
287 irc = nat->nat_aps->aps_data;
288 if (ippr_irc_complete(irc, ctcpbuf, dlen) == 0)
292 * check that IP address in the PORT/PASV reply is the same as the
293 * sender of the command - prevents using PORT for port scanning.
295 if (irc->irc_ipnum != ntohl(nat->nat_inip.s_addr))
301 * Calculate new address parts for the DCC command
303 a1 = ntohl(ip->ip_src.s_addr);
305 i = irc->irc_addr - ctcpbuf;
307 (void) strncpy(newbuf, ctcpbuf, i);
308 /* DO NOT change these! */
309 #if defined(SNPRINTF) && defined(KERNEL)
310 SNPRINTF(newbuf, sizeof(newbuf) - i, "%u %u\001\r\n", a1, a5);
312 (void) sprintf(newbuf, "%u %u\001\r\n", a1, a5);
315 nlen = strlen(newbuf);
318 if ((inc + ip->ip_len) > 65535)
322 for (m1 = m; m1->b_cont; m1 = m1->b_cont)
324 if ((inc > 0) && (m1->b_datap->db_lim - m1->b_wptr < inc)) {
327 /* alloc enough to keep same trailer space for lower driver */
328 nm = allocb(nlen, BPRI_MED);
329 PANIC((!nm),("ippr_irc_out: allocb failed"));
331 nm->b_band = m1->b_band;
335 PANIC((m1->b_wptr < m1->b_rptr),
336 ("ippr_irc_out: cannot handle fragmented data block"));
340 # if SOLARIS && defined(ICK_VALID)
341 if (m1->b_datap->db_struiolim == m1->b_wptr)
342 m1->b_datap->db_struiolim += inc;
343 m1->b_datap->db_struioflag &= ~STRUIO_IP;
350 /* the mbuf chain will be extended if necessary by m_copyback() */
352 COPYBACK(m, off, nlen, newbuf);
355 #if defined(MENTAT) || defined(__sgi)
356 register u_32_t sum1, sum2;
359 sum2 = ip->ip_len + inc;
361 /* Because ~1 == -2, We really need ~1 == -1 */
365 sum2 = (sum2 & 0xffff) + (sum2 >> 16);
367 fix_outcksum(fin, &ip->ip_sum, sum2);
373 * Add skeleton NAT entry for connection which will come back the
378 * Don't allow the PORT command to specify a port < 1024 due to
381 if (ntohs(sp) < 1024)
385 * The server may not make the connection back from port 20, but
386 * it is the most likely so use it here to check for a conflicting
389 bcopy((caddr_t)fin, (caddr_t)&fi, sizeof(fi));
391 fi.fin_data[1] = fin->fin_data[1];
392 nat2 = nat_outlookup(fin, IPN_TCP, nat->nat_p, nat->nat_inip,
395 bcopy((caddr_t)fin, (caddr_t)&fi, sizeof(fi));
396 bzero((char *)tcp2, sizeof(*tcp2));
397 tcp2->th_win = htons(8192);
399 tcp2->th_dport = 0; /* XXX - don't specify remote port */
402 fi.fin_data[0] = ntohs(sp);
404 fi.fin_dp = (char *)tcp2;
405 fi.fin_fr = &ircnatfr;
406 fi.fin_dlen = sizeof(*tcp2);
407 fi.fin_plen = fi.fin_hlen + sizeof(*tcp2);
409 ip->ip_src = nat->nat_inip;
410 nat2 = nat_new(&fi, nat->nat_ptr, NULL,
411 NAT_SLAVE|IPN_TCP|SI_W_DPORT, NAT_OUTBOUND);
413 (void) nat_proto(&fi, nat2, 0);
414 nat_update(&fi, nat2, nat2->nat_ptr);
416 (void) fr_addstate(&fi, NULL, SI_W_DPORT);
417 if (fi.fin_state != NULL)
418 fr_statederef((ipstate_t **)&fi.fin_state);
426 int ippr_irc_out(fin, aps, nat)
431 aps = aps; /* LINT */
432 return ippr_irc_send(fin, nat);