4 * Copyright (C) 2000-2003 Darren Reed
6 * See the IPFILTER.LICENCE file for details on licencing.
8 * Id: ip_irc_pxy.c,v 2.39.2.4 2005/02/04 10:22:55 darrenr Exp
13 #define IPF_IRCBUFSZ 96 /* This *MUST* be >= 64! */
16 int ippr_irc_init __P((void));
17 void ippr_irc_fini __P((void));
18 int ippr_irc_new __P((fr_info_t *, ap_session_t *, nat_t *));
19 int ippr_irc_out __P((fr_info_t *, ap_session_t *, nat_t *));
20 int ippr_irc_send __P((fr_info_t *, nat_t *));
21 int ippr_irc_complete __P((ircinfo_t *, char *, size_t));
22 u_short ipf_irc_atoi __P((char **));
24 static frentry_t ircnatfr;
26 int irc_proxy_init = 0;
30 * Initialize local structures.
34 bzero((char *)&ircnatfr, sizeof(ircnatfr));
36 ircnatfr.fr_flags = FR_INQUE|FR_PASS|FR_QUICK|FR_KEEPSTATE;
37 MUTEX_INIT(&ircnatfr.fr_lock, "IRC proxy rule lock");
46 if (irc_proxy_init == 1) {
47 MUTEX_DESTROY(&ircnatfr.fr_lock);
53 char *ippr_irc_dcctypes[] = {
54 "CHAT ", /* CHAT chat ipnumber portnumber */
55 "SEND ", /* SEND filename ipnumber portnumber */
64 * :A PRIVMSG B :^ADCC CHAT chat 0 0^A\r\n
65 * PRIVMSG B ^ADCC CHAT chat 0 0^A\r\n
69 int ippr_irc_complete(ircp, buf, len)
88 if ((c != ':') && (c != 'P'))
93 * Loosely check that the source is a nickname of some sort
101 for (c = *s; !ISSPACE(c) && (i > 0); i--)
108 ircp->irc_snick = NULL;
111 * Check command string
113 if (strncmp(s, "PRIVMSG ", 8))
121 * Loosely check that the destination is a nickname of some sort
125 for (; !ISSPACE(c) && (i > 0); i--)
133 * Look for a ^A to start the DCC
141 if (strncmp(s, "\001DCC ", 4))
148 * Check for a recognised DCC command
150 for (j = 0, k = 0; ippr_irc_dcctypes[j]; j++) {
151 k = MIN(strlen(ippr_irc_dcctypes[j]), i);
152 if (!strncmp(ippr_irc_dcctypes[j], s, k))
155 if (!ippr_irc_dcctypes[j])
172 for (; (c != ' ') && (c != '\001') && (i > 0); i--)
175 if (c == '\001') /* In reality a ^A can quote another ^A...*/
190 for (l = 0; ISDIGIT(c) && (i > 0); i--) {
211 for (l = 0; ISDIGIT(c) && (i > 0); i--) {
218 if (strncmp(s, "\001\r\n", 3))
221 ircp->irc_len = s - buf;
227 int ippr_irc_new(fin, aps, nat)
234 KMALLOC(irc, ircinfo_t *);
238 fin = fin; /* LINT */
239 nat = nat; /* LINT */
242 aps->aps_psiz = sizeof(ircinfo_t);
244 bzero((char *)irc, sizeof(*irc));
249 int ippr_irc_send(fin, nat)
253 char ctcpbuf[IPF_IRCBUFSZ], newbuf[IPF_IRCBUFSZ];
254 tcphdr_t *tcp, tcph, *tcp2 = &tcph;
255 int off, inc = 0, i, dlen;
256 size_t nlen = 0, olen;
271 tcp = (tcphdr_t *)fin->fin_dp;
272 bzero(ctcpbuf, sizeof(ctcpbuf));
273 off = (char *)tcp - (char *)ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff;
276 dlen = fin->fin_plen - off;
278 dlen = MSGDSIZE(m) - off;
282 COPYDATA(m, off, MIN(sizeof(ctcpbuf), dlen), ctcpbuf);
286 ctcpbuf[sizeof(ctcpbuf) - 1] = '\0';
289 irc = nat->nat_aps->aps_data;
290 if (ippr_irc_complete(irc, ctcpbuf, dlen) == 0)
294 * check that IP address in the PORT/PASV reply is the same as the
295 * sender of the command - prevents using PORT for port scanning.
297 if (irc->irc_ipnum != ntohl(nat->nat_inip.s_addr))
303 * Calculate new address parts for the DCC command
305 a1 = ntohl(ip->ip_src.s_addr);
307 i = irc->irc_addr - ctcpbuf;
309 (void) strncpy(newbuf, ctcpbuf, i);
310 /* DO NOT change these! */
311 #if defined(SNPRINTF) && defined(KERNEL)
312 SNPRINTF(newbuf, sizeof(newbuf) - i, "%u %u\001\r\n", a1, a5);
314 (void) sprintf(newbuf, "%u %u\001\r\n", a1, a5);
317 nlen = strlen(newbuf);
320 if ((inc + ip->ip_len) > 65535)
324 for (m1 = m; m1->b_cont; m1 = m1->b_cont)
326 if ((inc > 0) && (m1->b_datap->db_lim - m1->b_wptr < inc)) {
329 /* alloc enough to keep same trailer space for lower driver */
330 nm = allocb(nlen, BPRI_MED);
331 PANIC((!nm),("ippr_irc_out: allocb failed"));
333 nm->b_band = m1->b_band;
337 PANIC((m1->b_wptr < m1->b_rptr),
338 ("ippr_irc_out: cannot handle fragmented data block"));
342 # if SOLARIS && defined(ICK_VALID)
343 if (m1->b_datap->db_struiolim == m1->b_wptr)
344 m1->b_datap->db_struiolim += inc;
345 m1->b_datap->db_struioflag &= ~STRUIO_IP;
352 /* the mbuf chain will be extended if necessary by m_copyback() */
354 COPYBACK(m, off, nlen, newbuf);
357 #if defined(MENTAT) || defined(__sgi)
358 register u_32_t sum1, sum2;
361 sum2 = ip->ip_len + inc;
363 /* Because ~1 == -2, We really need ~1 == -1 */
367 sum2 = (sum2 & 0xffff) + (sum2 >> 16);
369 fix_outcksum(fin, &ip->ip_sum, sum2);
375 * Add skeleton NAT entry for connection which will come back the
380 * Don't allow the PORT command to specify a port < 1024 due to
383 if (ntohs(sp) < 1024)
387 * The server may not make the connection back from port 20, but
388 * it is the most likely so use it here to check for a conflicting
391 bcopy((caddr_t)fin, (caddr_t)&fi, sizeof(fi));
393 fi.fin_data[1] = fin->fin_data[1];
394 nat2 = nat_outlookup(fin, IPN_TCP, nat->nat_p, nat->nat_inip,
397 bcopy((caddr_t)fin, (caddr_t)&fi, sizeof(fi));
398 bzero((char *)tcp2, sizeof(*tcp2));
399 tcp2->th_win = htons(8192);
401 tcp2->th_dport = 0; /* XXX - don't specify remote port */
404 fi.fin_data[0] = ntohs(sp);
406 fi.fin_dp = (char *)tcp2;
407 fi.fin_fr = &ircnatfr;
408 fi.fin_dlen = sizeof(*tcp2);
409 fi.fin_plen = fi.fin_hlen + sizeof(*tcp2);
411 ip->ip_src = nat->nat_inip;
412 nat2 = nat_new(&fi, nat->nat_ptr, NULL,
413 NAT_SLAVE|IPN_TCP|SI_W_DPORT, NAT_OUTBOUND);
415 (void) nat_proto(&fi, nat2, 0);
416 nat_update(&fi, nat2, nat2->nat_ptr);
418 (void) fr_addstate(&fi, NULL, SI_W_DPORT);
419 if (fi.fin_state != NULL)
420 fr_statederef(&fi, (ipstate_t **)&fi.fin_state);
428 int ippr_irc_out(fin, aps, nat)
433 aps = aps; /* LINT */
434 return ippr_irc_send(fin, nat);