1 files changed, 287 insertions, 259 deletions

diff --git a/lib/libalias/alias_irc.c b/lib/libalias/alias_irc.c
index 3b2ff92..5785e54 100644
--- a/lib/libalias/alias_irc.c
+++ b/lib/libalias/alias_irc.c
@@ -65,277 +65,305 @@ __FBSDID("$FreeBSD$");
 
 
 void
-AliasHandleIrcOut(struct libalias *la, 
-				 struct ip *pip, /* IP packet to examine */
-				 struct alias_link *link,		  /* Which link are we on? */
-				 int maxsize		  /* Maximum size of IP packet including headers */
-				 )
+AliasHandleIrcOut(struct libalias *la,
+    struct ip *pip,		/* IP packet to examine */
+    struct alias_link *link,	/* Which link are we on? */
+    int maxsize			/* Maximum size of IP packet including
+				 * headers */
+)
 {
-    int hlen, tlen, dlen;
-    struct in_addr true_addr;
-    u_short true_port;
-    char *sptr;
-    struct tcphdr *tc;
-	 int i;							  /* Iterator through the source */
+	int hlen, tlen, dlen;
+	struct in_addr true_addr;
+	u_short true_port;
+	char *sptr;
+	struct tcphdr *tc;
+	int i;			/* Iterator through the source */
 
 /* Calculate data length of TCP packet */
-    tc = (struct tcphdr *) ((char *) pip + (pip->ip_hl << 2));
-    hlen = (pip->ip_hl + tc->th_off) << 2;
-    tlen = ntohs(pip->ip_len);
-    dlen = tlen - hlen;
-
-	 /* Return if data length is too short - assume an entire PRIVMSG in each packet. */
-    if (dlen<sizeof(":A!a@n.n PRIVMSG A :aDCC 1 1a")-1)
-        return;
+	tc = (struct tcphdr *)((char *)pip + (pip->ip_hl << 2));
+	hlen = (pip->ip_hl + tc->th_off) << 2;
+	tlen = ntohs(pip->ip_len);
+	dlen = tlen - hlen;
+
+	/*
+	 * Return if data length is too short - assume an entire PRIVMSG in
+	 * each packet.
+	 */
+	if (dlen < sizeof(":A!a@n.n PRIVMSG A :aDCC 1 1a") - 1)
+		return;
 
 /* Place string pointer at beginning of data */
-    sptr = (char *) pip;
-    sptr += hlen;
-	 maxsize -= hlen;				  /* We're interested in maximum size of data, not packet */
-
-	 /* Search for a CTCP command [Note 1] */
-	 for(	i=0; i<dlen; i++ ) {
-		 if(sptr[i]=='\001')
-			 goto lFOUND_CTCP;
-	 }
-	 return;					  /* No CTCP commands in  */
-	 /* Handle CTCP commands - the buffer may have to be copied */
+	sptr = (char *)pip;
+	sptr += hlen;
+	maxsize -= hlen;	/* We're interested in maximum size of
+				 * data, not packet */
+
+	/* Search for a CTCP command [Note 1] */
+	for (i = 0; i < dlen; i++) {
+		if (sptr[i] == '\001')
+			goto lFOUND_CTCP;
+	}
+	return;			/* No CTCP commands in  */
+	/* Handle CTCP commands - the buffer may have to be copied */
 lFOUND_CTCP:
-	 {
-		 char newpacket[65536];	  /* Estimate of maximum packet size :) */
-		 int  copyat = i;			  /* Same */
-		 int  iCopy = 0;			  /* How much data have we written to copy-back string? */
-		 unsigned long org_addr;  /* Original IP address */
-		 unsigned short org_port; /* Original source port address */
-	 lCTCP_START:
-		 if( i >= dlen || iCopy >= sizeof(newpacket) )
-			 goto lPACKET_DONE;
-		 newpacket[iCopy++] = sptr[i++];	/* Copy the CTCP start character */
-		 /* Start of a CTCP */
-		 if( i+4 >= dlen )		  /* Too short for DCC */
-			 goto lBAD_CTCP;
-		 if( sptr[i+0] != 'D' )
-			 goto lBAD_CTCP;
-		 if( sptr[i+1] != 'C' )
-			 goto lBAD_CTCP;
-		 if( sptr[i+2] != 'C' )
-			 goto lBAD_CTCP;
-		 if( sptr[i+3] != ' ' )
-			 goto lBAD_CTCP;
-		 /* We have a DCC command - handle it! */
-		 i+= 4;						  /* Skip "DCC " */
-		 if( iCopy+4 > sizeof(newpacket) )
-			 goto lPACKET_DONE;
-		 newpacket[iCopy++] = 'D';
-		 newpacket[iCopy++] = 'C';
-		 newpacket[iCopy++] = 'C';
-		 newpacket[iCopy++] = ' ';
-
-		 DBprintf(("Found DCC\n"));
-		 /* Skip any extra spaces (should not occur according to
-          protocol, but DCC breaks CTCP protocol anyway */
-		 while(sptr[i] == ' ') {
-			 if( ++i >= dlen) {
-				 DBprintf(("DCC packet terminated in just spaces\n"));
-				 goto lPACKET_DONE;
-			 }
-		 }
-
-		 DBprintf(("Transferring command...\n"));
-		 while(sptr[i] != ' ') {
-			 newpacket[iCopy++] = sptr[i];
-			 if( ++i >= dlen || iCopy >= sizeof(newpacket) ) {
-				 DBprintf(("DCC packet terminated during command\n"));
-				 goto lPACKET_DONE;
-			 }
-		 }
-		 /* Copy _one_ space */
-		 if( i+1 < dlen && iCopy < sizeof(newpacket) )
-			 newpacket[iCopy++] = sptr[i++];
-
-		 DBprintf(("Done command - removing spaces\n"));
-		 /* Skip any extra spaces (should not occur according to
-          protocol, but DCC breaks CTCP protocol anyway */
-		 while(sptr[i] == ' ') {
-			 if( ++i >= dlen ) {
-				 DBprintf(("DCC packet terminated in just spaces (post-command)\n"));
-				 goto lPACKET_DONE;
-			 }
-		 }
-
-		 DBprintf(("Transferring filename...\n"));
-		 while(sptr[i] != ' ') {
-			 newpacket[iCopy++] = sptr[i];
-			 if( ++i >= dlen || iCopy >= sizeof(newpacket) ) {
-				 DBprintf(("DCC packet terminated during filename\n"));
-				 goto lPACKET_DONE;
-			 }
-		 }
-		 /* Copy _one_ space */
-		 if( i+1 < dlen && iCopy < sizeof(newpacket) )
-			 newpacket[iCopy++] = sptr[i++];
-
-		 DBprintf(("Done filename - removing spaces\n"));
-		 /* Skip any extra spaces (should not occur according to
-          protocol, but DCC breaks CTCP protocol anyway */
-		 while(sptr[i] == ' ') {
-			 if( ++i >= dlen ) {
-				 DBprintf(("DCC packet terminated in just spaces (post-filename)\n"));
-				 goto lPACKET_DONE;
-			 }
-		 }
-
-		 DBprintf(("Fetching IP address\n"));
-		 /* Fetch IP address */
-		 org_addr = 0;
-		 while(i<dlen && isdigit(sptr[i])) {
-			 if( org_addr > ULONG_MAX/10UL )	{ /* Terminate on overflow */
-				 DBprintf(("DCC Address overflow (org_addr == 0x%08lx, next char %c\n", org_addr, sptr[i]));
-				 goto lBAD_CTCP;
-			 }
-			 org_addr *= 10;
-			 org_addr += sptr[i++]-'0';
-		 }
-		 DBprintf(("Skipping space\n"));
-		 if( i+1 >= dlen || sptr[i] != ' ' ) {
-			 DBprintf(("Overflow (%d >= %d) or bad character (%02x) terminating IP address\n", i+1, dlen, sptr[i]));
-			 goto lBAD_CTCP;
-		 }
-		 /* Skip any extra spaces (should not occur according to
-          protocol, but DCC breaks CTCP protocol anyway, so we might
-          as well play it safe */
-		 while(sptr[i] == ' ') {
-			 if( ++i >= dlen ) {
-				 DBprintf(("Packet failure - space overflow.\n"));
-				 goto lPACKET_DONE;
-			 }
-		 }
-		 DBprintf(("Fetching port number\n"));
-		 /* Fetch source port */
-		 org_port = 0;
-		 while(i<dlen && isdigit(sptr[i])) {
-			 if( org_port > 6554 )	{ /* Terminate on overflow (65536/10 rounded up*/
-				 DBprintf(("DCC: port number overflow\n"));
-				 goto lBAD_CTCP;
-			 }
-			 org_port *= 10;
-			 org_port += sptr[i++]-'0';
-		 }
-		 /* Skip illegal addresses (or early termination) */
-		 if( i >= dlen || (sptr[i] != '\001' && sptr[i] != ' ') ) {
-			 DBprintf(("Bad port termination\n"));
-			 goto lBAD_CTCP;
-		 }
-		 DBprintf(("Got IP %lu and port %u\n", org_addr, (unsigned)org_port));
-
-		 /* We've got the address and port - now alias it */
-		 {
-			 struct alias_link *dcc_link;
-			 struct in_addr destaddr;
-
-
-			 true_port = htons(org_port);
-			 true_addr.s_addr = htonl(org_addr);
-			 destaddr.s_addr = 0;
-
-			 /* Sanity/Security checking */
-			 if (!org_addr || !org_port ||
-			     pip->ip_src.s_addr != true_addr.s_addr ||
-			     org_port < IPPORT_RESERVED)
-				 goto lBAD_CTCP;
-
-			 /* Steal the FTP_DATA_PORT - it doesn't really matter, and this
-				 would probably allow it through at least _some_
-				 firewalls. */
-			 dcc_link = FindUdpTcpOut(la, true_addr, destaddr,
-						  true_port, 0,
-						  IPPROTO_TCP, 1);
-			 DBprintf(("Got a DCC link\n"));
-			 if ( dcc_link ) {
-				 struct in_addr alias_address;	/* Address from aliasing */
-				 u_short alias_port;	/* Port given by aliasing */
-				 int n;
+	{
+		char newpacket[65536];	/* Estimate of maximum packet size
+					 * :) */
+		int copyat = i;	/* Same */
+		int iCopy = 0;	/* How much data have we written to
+				 * copy-back string? */
+		unsigned long org_addr;	/* Original IP address */
+		unsigned short org_port;	/* Original source port
+						 * address */
+
+lCTCP_START:
+		if (i >= dlen || iCopy >= sizeof(newpacket))
+			goto lPACKET_DONE;
+		newpacket[iCopy++] = sptr[i++];	/* Copy the CTCP start
+						 * character */
+		/* Start of a CTCP */
+		if (i + 4 >= dlen)	/* Too short for DCC */
+			goto lBAD_CTCP;
+		if (sptr[i + 0] != 'D')
+			goto lBAD_CTCP;
+		if (sptr[i + 1] != 'C')
+			goto lBAD_CTCP;
+		if (sptr[i + 2] != 'C')
+			goto lBAD_CTCP;
+		if (sptr[i + 3] != ' ')
+			goto lBAD_CTCP;
+		/* We have a DCC command - handle it! */
+		i += 4;		/* Skip "DCC " */
+		if (iCopy + 4 > sizeof(newpacket))
+			goto lPACKET_DONE;
+		newpacket[iCopy++] = 'D';
+		newpacket[iCopy++] = 'C';
+		newpacket[iCopy++] = 'C';
+		newpacket[iCopy++] = ' ';
+
+		DBprintf(("Found DCC\n"));
+		/*
+		 * Skip any extra spaces (should not occur according to
+		 * protocol, but DCC breaks CTCP protocol anyway
+		 */
+		while (sptr[i] == ' ') {
+			if (++i >= dlen) {
+				DBprintf(("DCC packet terminated in just spaces\n"));
+				goto lPACKET_DONE;
+			}
+		}
+
+		DBprintf(("Transferring command...\n"));
+		while (sptr[i] != ' ') {
+			newpacket[iCopy++] = sptr[i];
+			if (++i >= dlen || iCopy >= sizeof(newpacket)) {
+				DBprintf(("DCC packet terminated during command\n"));
+				goto lPACKET_DONE;
+			}
+		}
+		/* Copy _one_ space */
+		if (i + 1 < dlen && iCopy < sizeof(newpacket))
+			newpacket[iCopy++] = sptr[i++];
+
+		DBprintf(("Done command - removing spaces\n"));
+		/*
+		 * Skip any extra spaces (should not occur according to
+		 * protocol, but DCC breaks CTCP protocol anyway
+		 */
+		while (sptr[i] == ' ') {
+			if (++i >= dlen) {
+				DBprintf(("DCC packet terminated in just spaces (post-command)\n"));
+				goto lPACKET_DONE;
+			}
+		}
+
+		DBprintf(("Transferring filename...\n"));
+		while (sptr[i] != ' ') {
+			newpacket[iCopy++] = sptr[i];
+			if (++i >= dlen || iCopy >= sizeof(newpacket)) {
+				DBprintf(("DCC packet terminated during filename\n"));
+				goto lPACKET_DONE;
+			}
+		}
+		/* Copy _one_ space */
+		if (i + 1 < dlen && iCopy < sizeof(newpacket))
+			newpacket[iCopy++] = sptr[i++];
+
+		DBprintf(("Done filename - removing spaces\n"));
+		/*
+		 * Skip any extra spaces (should not occur according to
+		 * protocol, but DCC breaks CTCP protocol anyway
+		 */
+		while (sptr[i] == ' ') {
+			if (++i >= dlen) {
+				DBprintf(("DCC packet terminated in just spaces (post-filename)\n"));
+				goto lPACKET_DONE;
+			}
+		}
+
+		DBprintf(("Fetching IP address\n"));
+		/* Fetch IP address */
+		org_addr = 0;
+		while (i < dlen && isdigit(sptr[i])) {
+			if (org_addr > ULONG_MAX / 10UL) {	/* Terminate on overflow */
+				DBprintf(("DCC Address overflow (org_addr == 0x%08lx, next char %c\n", org_addr, sptr[i]));
+				goto lBAD_CTCP;
+			}
+			org_addr *= 10;
+			org_addr += sptr[i++] - '0';
+		}
+		DBprintf(("Skipping space\n"));
+		if (i + 1 >= dlen || sptr[i] != ' ') {
+			DBprintf(("Overflow (%d >= %d) or bad character (%02x) terminating IP address\n", i + 1, dlen, sptr[i]));
+			goto lBAD_CTCP;
+		}
+		/*
+		 * Skip any extra spaces (should not occur according to
+		 * protocol, but DCC breaks CTCP protocol anyway, so we
+		 * might as well play it safe
+		 */
+		while (sptr[i] == ' ') {
+			if (++i >= dlen) {
+				DBprintf(("Packet failure - space overflow.\n"));
+				goto lPACKET_DONE;
+			}
+		}
+		DBprintf(("Fetching port number\n"));
+		/* Fetch source port */
+		org_port = 0;
+		while (i < dlen && isdigit(sptr[i])) {
+			if (org_port > 6554) {	/* Terminate on overflow
+						 * (65536/10 rounded up */
+				DBprintf(("DCC: port number overflow\n"));
+				goto lBAD_CTCP;
+			}
+			org_port *= 10;
+			org_port += sptr[i++] - '0';
+		}
+		/* Skip illegal addresses (or early termination) */
+		if (i >= dlen || (sptr[i] != '\001' && sptr[i] != ' ')) {
+			DBprintf(("Bad port termination\n"));
+			goto lBAD_CTCP;
+		}
+		DBprintf(("Got IP %lu and port %u\n", org_addr, (unsigned)org_port));
+
+		/* We've got the address and port - now alias it */
+		{
+			struct alias_link *dcc_link;
+			struct in_addr destaddr;
+
+
+			true_port = htons(org_port);
+			true_addr.s_addr = htonl(org_addr);
+			destaddr.s_addr = 0;
+
+			/* Sanity/Security checking */
+			if (!org_addr || !org_port ||
+			    pip->ip_src.s_addr != true_addr.s_addr ||
+			    org_port < IPPORT_RESERVED)
+				goto lBAD_CTCP;
+
+			/*
+			 * Steal the FTP_DATA_PORT - it doesn't really
+			 * matter, and this would probably allow it through
+			 * at least _some_ firewalls.
+			 */
+			dcc_link = FindUdpTcpOut(la, true_addr, destaddr,
+			    true_port, 0,
+			    IPPROTO_TCP, 1);
+			DBprintf(("Got a DCC link\n"));
+			if (dcc_link) {
+				struct in_addr alias_address;	/* Address from aliasing */
+				u_short alias_port;	/* Port given by
+							 * aliasing */
+				int n;
 
 #ifndef NO_FW_PUNCH
-				 /* Generate firewall hole as appropriate */
-				 PunchFWHole(dcc_link);
+				/* Generate firewall hole as appropriate */
+				PunchFWHole(dcc_link);
 #endif
 
-				 alias_address = GetAliasAddress(link);
-				 n = snprintf(&newpacket[iCopy],
-										 sizeof(newpacket)-iCopy,
-										 "%lu ", (u_long)htonl(alias_address.s_addr));
-				 if( n < 0 ) {
-					 DBprintf(("DCC packet construct failure.\n"));
-					 goto lBAD_CTCP;
-				 }
-				 if( (iCopy += n) >= sizeof(newpacket) ) { /* Truncated/fit exactly - bad news */
-					 DBprintf(("DCC constructed packet overflow.\n"));
-					 goto lBAD_CTCP;
-				 }
-				 alias_port = GetAliasPort(dcc_link);
-				 n = snprintf(&newpacket[iCopy],
-										 sizeof(newpacket)-iCopy,
-										 "%u", htons(alias_port) );
-				 if( n < 0 ) {
-					 DBprintf(("DCC packet construct failure.\n"));
-					 goto lBAD_CTCP;
-				 }
-				 iCopy += n;
-				 /* Done - truncated cases will be taken care of by lBAD_CTCP */
-				 DBprintf(("Aliased IP %lu and port %u\n", alias_address.s_addr, (unsigned)alias_port));
-			 }
-		 }
-		 /* An uninteresting CTCP - state entered right after '\001' has
-          been pushed.  Also used to copy the rest of a DCC, after IP
-          address and port has been handled */
-	 lBAD_CTCP:
-		 for(; i<dlen && iCopy<sizeof(newpacket); i++,iCopy++) {
-			 newpacket[iCopy] = sptr[i]; /* Copy CTCP unchanged */
-			 if(sptr[i] == '\001') {
-				 goto lNORMAL_TEXT;
-			 }
-		 }
-		 goto lPACKET_DONE;
-		 /* Normal text */
-	 lNORMAL_TEXT:
-		 for(; i<dlen && iCopy<sizeof(newpacket); i++,iCopy++) {
-			 newpacket[iCopy] = sptr[i]; /* Copy CTCP unchanged */
-			 if(sptr[i] == '\001') {
-				 goto lCTCP_START;
-			 }
-		 }
-		 /* Handle the end of a packet */
-	 lPACKET_DONE:
-		 iCopy = iCopy > maxsize-copyat ? maxsize-copyat : iCopy;
-		 memcpy(sptr+copyat, newpacket, iCopy);
+				alias_address = GetAliasAddress(link);
+				n = snprintf(&newpacket[iCopy],
+				    sizeof(newpacket) - iCopy,
+				    "%lu ", (u_long) htonl(alias_address.s_addr));
+				if (n < 0) {
+					DBprintf(("DCC packet construct failure.\n"));
+					goto lBAD_CTCP;
+				}
+				if ((iCopy += n) >= sizeof(newpacket)) {	/* Truncated/fit exactly
+										 * - bad news */
+					DBprintf(("DCC constructed packet overflow.\n"));
+					goto lBAD_CTCP;
+				}
+				alias_port = GetAliasPort(dcc_link);
+				n = snprintf(&newpacket[iCopy],
+				    sizeof(newpacket) - iCopy,
+				    "%u", htons(alias_port));
+				if (n < 0) {
+					DBprintf(("DCC packet construct failure.\n"));
+					goto lBAD_CTCP;
+				}
+				iCopy += n;
+				/*
+				 * Done - truncated cases will be taken
+				 * care of by lBAD_CTCP
+				 */
+				DBprintf(("Aliased IP %lu and port %u\n", alias_address.s_addr, (unsigned)alias_port));
+			}
+		}
+		/*
+		 * An uninteresting CTCP - state entered right after '\001'
+		 * has been pushed.  Also used to copy the rest of a DCC,
+		 * after IP address and port has been handled
+		 */
+lBAD_CTCP:
+		for (; i < dlen && iCopy < sizeof(newpacket); i++, iCopy++) {
+			newpacket[iCopy] = sptr[i];	/* Copy CTCP unchanged */
+			if (sptr[i] == '\001') {
+				goto lNORMAL_TEXT;
+			}
+		}
+		goto lPACKET_DONE;
+		/* Normal text */
+lNORMAL_TEXT:
+		for (; i < dlen && iCopy < sizeof(newpacket); i++, iCopy++) {
+			newpacket[iCopy] = sptr[i];	/* Copy CTCP unchanged */
+			if (sptr[i] == '\001') {
+				goto lCTCP_START;
+			}
+		}
+		/* Handle the end of a packet */
+lPACKET_DONE:
+		iCopy = iCopy > maxsize - copyat ? maxsize - copyat : iCopy;
+		memcpy(sptr + copyat, newpacket, iCopy);
 
 /* Save information regarding modified seq and ack numbers */
-        {
-            int delta;
-
-            SetAckModified(link);
-            delta = GetDeltaSeqOut(pip, link);
-            AddSeq(pip, link, delta+copyat+iCopy-dlen);
-        }
-
-		  /* Revise IP header */
-        {
-			  u_short new_len;
-
-			  new_len = htons(hlen + iCopy + copyat);
-			  DifferentialChecksum(&pip->ip_sum,
-										  &new_len,
-										  &pip->ip_len,
-										  1);
-			  pip->ip_len = new_len;
-        }
-
-		  /* Compute TCP checksum for revised packet */
-        tc->th_sum = 0;
-        tc->th_sum = TcpChecksum(pip);
-		  return;
-	 }
+		{
+			int delta;
+
+			SetAckModified(link);
+			delta = GetDeltaSeqOut(pip, link);
+			AddSeq(pip, link, delta + copyat + iCopy - dlen);
+		}
+
+		/* Revise IP header */
+		{
+			u_short new_len;
+
+			new_len = htons(hlen + iCopy + copyat);
+			DifferentialChecksum(&pip->ip_sum,
+			    &new_len,
+			    &pip->ip_len,
+			    1);
+			pip->ip_len = new_len;
+		}
+
+		/* Compute TCP checksum for revised packet */
+		tc->th_sum = 0;
+		tc->th_sum = TcpChecksum(pip);
+		return;
+	}
 }
 
 /* Notes: