Function AliasHandleIrcOut

freebsd/netinet/libalias/alias_irc.c:166–469

#endif

static void
AliasHandleIrcOut(struct libalias *la,
    struct ip *pip,		/* IP packet to examine */
    struct alias_link *lnk,	/* 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 */

/* Calculate data length of TCP packet */
	tc = (struct tcphdr *)ip_next(pip);
	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 < (int)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 */
lFOUND_CTCP:
	{
		unsigned int copyat = i;
		unsigned 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 >= PKTSIZE)
			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;