import ipfilter 4.1.8 into the kernel source tree

1 files changed, 435 insertions, 0 deletions

diff --git a/sys/contrib/ipfilter/netinet/ip_irc_pxy.c b/sys/contrib/ipfilter/netinet/ip_irc_pxy.c
new file mode 100644
index 0000000..0f61d76
--- /dev/null
+++ b/sys/contrib/ipfilter/netinet/ip_irc_pxy.c
@@ -0,0 +1,435 @@
+/*	$FreeBSD$	*/
+
+/*
+ * Copyright (C) 2000-2003 Darren Reed
+ *
+ * See the IPFILTER.LICENCE file for details on licencing.
+ *
+ * Id: ip_irc_pxy.c,v 2.39.2.4 2005/02/04 10:22:55 darrenr Exp
+ */
+
+#define	IPF_IRC_PROXY
+
+#define	IPF_IRCBUFSZ	96	/* This *MUST* be >= 64! */
+
+
+int ippr_irc_init __P((void));
+void ippr_irc_fini __P((void));
+int ippr_irc_new __P((fr_info_t *, ap_session_t *, nat_t *));
+int ippr_irc_out __P((fr_info_t *, ap_session_t *, nat_t *));
+int ippr_irc_send __P((fr_info_t *, nat_t *));
+int ippr_irc_complete __P((ircinfo_t *, char *, size_t));
+u_short ipf_irc_atoi __P((char **));
+
+static	frentry_t	ircnatfr;
+
+int	irc_proxy_init = 0;
+
+
+/*
+ * Initialize local structures.
+ */
+int ippr_irc_init()
+{
+	bzero((char *)&ircnatfr, sizeof(ircnatfr));
+	ircnatfr.fr_ref = 1;
+	ircnatfr.fr_flags = FR_INQUE|FR_PASS|FR_QUICK|FR_KEEPSTATE;
+	MUTEX_INIT(&ircnatfr.fr_lock, "IRC proxy rule lock");
+	irc_proxy_init = 1;
+
+	return 0;
+}
+
+
+void ippr_irc_fini()
+{
+	if (irc_proxy_init == 1) {
+		MUTEX_DESTROY(&ircnatfr.fr_lock);
+		irc_proxy_init = 0;
+	}
+}
+
+
+char *ippr_irc_dcctypes[] = {
+	"CHAT ",	/* CHAT chat ipnumber portnumber */
+	"SEND ",	/* SEND filename ipnumber portnumber */
+	"MOVE ",
+	"TSEND ",
+	"SCHAT ",
+	NULL,
+};
+
+
+/*
+ * :A PRIVMSG B :^ADCC CHAT chat 0 0^A\r\n
+ * PRIVMSG B ^ADCC CHAT chat 0 0^A\r\n
+ */
+
+
+int ippr_irc_complete(ircp, buf, len)
+ircinfo_t *ircp;
+char *buf;
+size_t len;
+{
+	register char *s, c;
+	register size_t i;
+	u_32_t l;
+	int j, k;
+
+	ircp->irc_ipnum = 0;
+	ircp->irc_port = 0;
+
+	if (len < 31)
+		return 0;
+	s = buf;
+	c = *s++;
+	i = len - 1;
+
+	if ((c != ':') && (c != 'P'))
+		return 0;
+
+	if (c == ':') {
+		/*
+		 * Loosely check that the source is a nickname of some sort
+		 */
+		s++;
+		c = *s;
+		ircp->irc_snick = s;
+		if (!ISALPHA(c))
+			return 0;
+		i--;
+		for (c = *s; !ISSPACE(c) && (i > 0); i--)
+			c = *s++;
+		if (i < 31)
+			return 0;
+		if (c != 'P')
+			return 0;
+	} else
+		ircp->irc_snick = NULL;
+
+	/*
+	 * Check command string
+	 */
+	if (strncmp(s, "PRIVMSG ", 8))
+		return 0;
+	i -= 8;
+	s += 8;
+	c = *s;
+	ircp->irc_dnick = s;
+
+	/*
+	 * Loosely check that the destination is a nickname of some sort
+	 */
+	if (!ISALPHA(c))
+		return 0;
+	for (; !ISSPACE(c) && (i > 0); i--)
+		c = *s++;
+	if (i < 20)
+		return 0;
+	s++,
+	i--;
+
+	/*
+	 * Look for a ^A to start the DCC
+	 */
+	c = *s;
+	if (c == ':') {
+		s++;
+		c = *s;
+	}
+
+	if (strncmp(s, "\001DCC ", 4))
+		return 0;
+
+	i -= 4;
+	s += 4;
+
+	/*
+	 * Check for a recognised DCC command
+	 */
+	for (j = 0, k = 0; ippr_irc_dcctypes[j]; j++) {
+		k = MIN(strlen(ippr_irc_dcctypes[j]), i);
+		if (!strncmp(ippr_irc_dcctypes[j], s, k))
+			break;
+	}
+	if (!ippr_irc_dcctypes[j])
+		return 0;
+
+	ircp->irc_type = s;
+	i -= k;
+	s += k;
+
+	if (i < 11)
+		return 0;
+
+	/*
+	 * Check for the arg
+	 */
+	c = *s;
+	if (ISSPACE(c))
+		return 0;
+	ircp->irc_arg = s;
+	for (; (c != ' ') && (c != '\001') && (i > 0); i--)
+		c = *s++;
+
+	if (c == '\001')	/* In reality a ^A can quote another ^A...*/
+		return 0;
+
+	if (i < 5)
+		return 0;
+
+	s++;
+	i--;
+	c = *s;
+	if (!ISDIGIT(c))
+		return 0;
+	ircp->irc_addr = s;
+	/*
+	 * Get the IP#
+	 */
+	for (l = 0; ISDIGIT(c) && (i > 0); i--) {
+		l *= 10;
+		l += c - '0';
+		c = *s++;
+	}
+
+	if (i < 4)
+		return 0;
+
+	if (c != ' ')
+		return 0;
+
+	ircp->irc_ipnum = l;
+	s++;
+	i--;
+	c = *s;
+	if (!ISDIGIT(c))
+		return 0;
+	/*
+	 * Get the port#
+	 */
+	for (l = 0; ISDIGIT(c) && (i > 0); i--) {
+		l *= 10;
+		l += c - '0';
+		c = *s++;
+	}
+	if (i < 3)
+		return 0;
+	if (strncmp(s, "\001\r\n", 3))
+		return 0;
+	s += 3;
+	ircp->irc_len = s - buf;
+	ircp->irc_port = l;
+	return 1;
+}
+
+
+int ippr_irc_new(fin, aps, nat)
+fr_info_t *fin;
+ap_session_t *aps;
+nat_t *nat;
+{
+	ircinfo_t *irc;
+
+	KMALLOC(irc, ircinfo_t *);
+	if (irc == NULL)
+		return -1;
+
+	fin = fin;	/* LINT */
+	nat = nat;	/* LINT */
+
+	aps->aps_data = irc;
+	aps->aps_psiz = sizeof(ircinfo_t);
+
+	bzero((char *)irc, sizeof(*irc));
+	return 0;
+}
+
+
+int ippr_irc_send(fin, nat)
+fr_info_t *fin;
+nat_t *nat;
+{
+	char ctcpbuf[IPF_IRCBUFSZ], newbuf[IPF_IRCBUFSZ];
+	tcphdr_t *tcp, tcph, *tcp2 = &tcph;
+	int off, inc = 0, i, dlen;
+	size_t nlen = 0, olen;
+	struct in_addr swip;
+	u_short a5, sp;
+	ircinfo_t *irc;
+	fr_info_t fi;
+	nat_t *nat2;
+	u_int a1;
+	ip_t *ip;
+	mb_t *m;
+#ifdef	MENTAT
+	mb_t *m1;
+#endif
+
+	m = fin->fin_m;
+	ip = fin->fin_ip;
+	tcp = (tcphdr_t *)fin->fin_dp;
+	bzero(ctcpbuf, sizeof(ctcpbuf));
+	off = (char *)tcp - (char *)ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff;
+
+#ifdef __sgi
+	dlen = fin->fin_plen - off;
+#else
+	dlen = MSGDSIZE(m) - off;
+#endif
+	if (dlen <= 0)
+		return 0;
+	COPYDATA(m, off, MIN(sizeof(ctcpbuf), dlen), ctcpbuf);
+
+	if (dlen <= 0)
+		return 0;
+	ctcpbuf[sizeof(ctcpbuf) - 1] = '\0';
+	*newbuf = '\0';
+
+	irc = nat->nat_aps->aps_data;
+	if (ippr_irc_complete(irc, ctcpbuf, dlen) == 0)
+		return 0;
+
+	/*
+	 * check that IP address in the PORT/PASV reply is the same as the
+	 * sender of the command - prevents using PORT for port scanning.
+	 */
+	if (irc->irc_ipnum != ntohl(nat->nat_inip.s_addr))
+		return 0;
+
+	a5 = irc->irc_port;
+
+	/*
+	 * Calculate new address parts for the DCC command
+	 */
+	a1 = ntohl(ip->ip_src.s_addr);
+	olen = irc->irc_len;
+	i = irc->irc_addr - ctcpbuf;
+	i++;
+	(void) strncpy(newbuf, ctcpbuf, i);
+	/* DO NOT change these! */
+#if defined(SNPRINTF) && defined(KERNEL)
+	SNPRINTF(newbuf, sizeof(newbuf) - i, "%u %u\001\r\n", a1, a5);
+#else
+	(void) sprintf(newbuf, "%u %u\001\r\n", a1, a5);
+#endif
+
+	nlen = strlen(newbuf);
+	inc = nlen - olen;
+
+	if ((inc + ip->ip_len) > 65535)
+		return 0;
+
+#ifdef	MENTAT
+	for (m1 = m; m1->b_cont; m1 = m1->b_cont)
+		;
+	if ((inc > 0) && (m1->b_datap->db_lim - m1->b_wptr < inc)) {
+		mblk_t *nm;
+
+		/* alloc enough to keep same trailer space for lower driver */
+		nm = allocb(nlen, BPRI_MED);
+		PANIC((!nm),("ippr_irc_out: allocb failed"));
+
+		nm->b_band = m1->b_band;
+		nm->b_wptr += nlen;
+
+		m1->b_wptr -= olen;
+		PANIC((m1->b_wptr < m1->b_rptr),
+		      ("ippr_irc_out: cannot handle fragmented data block"));
+
+		linkb(m1, nm);
+	} else {
+# if SOLARIS && defined(ICK_VALID)
+		if (m1->b_datap->db_struiolim == m1->b_wptr)
+			m1->b_datap->db_struiolim += inc;
+		m1->b_datap->db_struioflag &= ~STRUIO_IP;
+# endif
+		m1->b_wptr += inc;
+	}
+#else
+	if (inc < 0)
+		m_adj(m, inc);
+	/* the mbuf chain will be extended if necessary by m_copyback() */
+#endif
+	COPYBACK(m, off, nlen, newbuf);
+
+	if (inc != 0) {
+#if defined(MENTAT) || defined(__sgi)
+		register u_32_t	sum1, sum2;
+
+		sum1 = ip->ip_len;
+		sum2 = ip->ip_len + inc;
+
+		/* Because ~1 == -2, We really need ~1 == -1 */
+		if (sum1 > sum2)
+			sum2--;
+		sum2 -= sum1;
+		sum2 = (sum2 & 0xffff) + (sum2 >> 16);
+
+		fix_outcksum(fin, &ip->ip_sum, sum2);
+#endif
+		ip->ip_len += inc;
+	}
+
+	/*
+	 * Add skeleton NAT entry for connection which will come back the
+	 * other way.
+	 */
+	sp = htons(a5);
+	/*
+	 * Don't allow the PORT command to specify a port < 1024 due to
+	 * security crap.
+	 */
+	if (ntohs(sp) < 1024)
+		return 0;
+
+	/*
+	 * The server may not make the connection back from port 20, but
+	 * it is the most likely so use it here to check for a conflicting
+	 * mapping.
+	 */
+	bcopy((caddr_t)fin, (caddr_t)&fi, sizeof(fi));
+	fi.fin_data[0] = sp;
+	fi.fin_data[1] = fin->fin_data[1];
+	nat2 = nat_outlookup(fin, IPN_TCP, nat->nat_p, nat->nat_inip,
+			     ip->ip_dst);
+	if (nat2 == NULL) {
+		bcopy((caddr_t)fin, (caddr_t)&fi, sizeof(fi));
+		bzero((char *)tcp2, sizeof(*tcp2));
+		tcp2->th_win = htons(8192);
+		tcp2->th_sport = sp;
+		tcp2->th_dport = 0; /* XXX - don't specify remote port */
+		fi.fin_state = NULL;
+		fi.fin_nat = NULL;
+		fi.fin_data[0] = ntohs(sp);
+		fi.fin_data[1] = 0;
+		fi.fin_dp = (char *)tcp2;
+		fi.fin_fr = &ircnatfr;
+		fi.fin_dlen = sizeof(*tcp2);
+		fi.fin_plen = fi.fin_hlen + sizeof(*tcp2);
+		swip = ip->ip_src;
+		ip->ip_src = nat->nat_inip;
+		nat2 = nat_new(&fi, nat->nat_ptr, NULL,
+			       NAT_SLAVE|IPN_TCP|SI_W_DPORT, NAT_OUTBOUND);
+		if (nat2 != NULL) {
+			(void) nat_proto(&fi, nat2, 0);
+			nat_update(&fi, nat2, nat2->nat_ptr);
+
+			(void) fr_addstate(&fi, NULL, SI_W_DPORT);
+			if (fi.fin_state != NULL)
+				fr_statederef(&fi, (ipstate_t **)&fi.fin_state);
+		}
+		ip->ip_src = swip;
+	}
+	return inc;
+}
+
+
+int ippr_irc_out(fin, aps, nat)
+fr_info_t *fin;
+ap_session_t *aps;
+nat_t *nat;
+{
+	aps = aps;	/* LINT */
+	return ippr_irc_send(fin, nat);
+}