22  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
82 	if (ah->dport == NULL || ah->sport == NULL || ah->lnk == NULL)  in fingerprint()
83 		return (-1);  in fingerprint()
84 	if (ntohs(*ah->dport) == PPTP_CONTROL_PORT_NUMBER  in fingerprint()
85 	    || ntohs(*ah->sport) == PPTP_CONTROL_PORT_NUMBER)  in fingerprint()
87 	return (-1);  in fingerprint()
99 	AliasHandlePptpIn(la, pip, ah->lnk);  in protohandlerin()
106 	AliasHandlePptpOut(la, pip, ah->lnk);  in protohandlerout()
113 	if (la->packetAliasMode & PKT_ALIAS_PROXY_ONLY ||  in protohandlergrein()
116 	return (-1);  in protohandlergrein()
124 	return (-1);  in protohandlergreout()
173 		break;  in mod_handler()
177 		break;  in mod_handler()
199    Specifically, watch PPTP control messages and alias the Call ID or the
201    "de-aliasing" of incoming packets, this is different than any other
208    For this routine to work, the PPTP control messages must fit entirely
213    IRC and RTSP), the PPTP control messages that need to be aliased are
270 	u_int16_t	type;	/* control message type */
292     struct alias_link *lnk)	/* The PPTP control link */  in AliasHandlePptpOut()
297 	u_int16_t ctl_type;	/* control message type */  in AliasHandlePptpOut()
300 	/* Verify valid PPTP control message */  in AliasHandlePptpOut()
312 		 * control message.  in AliasHandlePptpOut()
315 		    GetAliasAddress(lnk), cptr->cid1);  in AliasHandlePptpOut()
316 		break;  in AliasHandlePptpOut()
320 		 * Find PPTP link for address and Call ID found in control  in AliasHandlePptpOut()
324 		    GetDestAddress(lnk), cptr->cid1);  in AliasHandlePptpOut()
325 		break;  in AliasHandlePptpOut()
331 		int accumulate = cptr->cid1;  in AliasHandlePptpOut()
334 		cptr->cid1 = GetAliasPort(pptp_lnk);  in AliasHandlePptpOut()
338 		accumulate -= cptr->cid1;  in AliasHandlePptpOut()
339 		ADJUST_CHECKSUM(accumulate, tc->th_sum);  in AliasHandlePptpOut()
345 			if (codes->resCode == 1)  in AliasHandlePptpOut()
348 				SetDestCallId(pptp_lnk, cptr->cid2);  in AliasHandlePptpOut()
352 			break;  in AliasHandlePptpOut()
356 			break;  in AliasHandlePptpOut()
364     struct alias_link *lnk)	/* The PPTP control link */  in AliasHandlePptpIn()
369 	u_int16_t ctl_type;	/* control message type */  in AliasHandlePptpIn()
372 	/* Verify valid PPTP control message */  in AliasHandlePptpIn()
381 		pcall_id = &cptr->cid1;  in AliasHandlePptpIn()
382 		break;  in AliasHandlePptpIn()
385 		pcall_id = &cptr->cid2;  in AliasHandlePptpIn()
386 		break;  in AliasHandlePptpIn()
390 		    GetAliasAddress(lnk), cptr->cid1);  in AliasHandlePptpIn()
398 	/* Find PPTP link for address and Call ID found in PPTP Control Msg */  in AliasHandlePptpIn()
405 		/* De-alias the Peer's Call Id. */  in AliasHandlePptpIn()
410 		accumulate -= *pcall_id;  in AliasHandlePptpIn()
411 		ADJUST_CHECKSUM(accumulate, tc->th_sum);  in AliasHandlePptpIn()
417 			if (codes->resCode == 1)  in AliasHandlePptpIn()
420 				SetDestCallId(pptp_lnk, cptr->cid1);  in AliasHandlePptpIn()
437 	hlen = (pip->ip_hl + tc->th_off) << 2;  in AliasVerifyPptp()
438 	tlen = ntohs(pip->ip_len);  in AliasVerifyPptp()
439 	dlen = tlen - hlen;  in AliasVerifyPptp()
448 	/* Return the control message type */  in AliasVerifyPptp()
449 	*ptype = ntohs(hptr->type);  in AliasVerifyPptp()
451 	/* Verify PPTP Control Message */  in AliasVerifyPptp()
452 	if ((ntohs(hptr->msgType) != PPTP_CTRL_MSG_TYPE) ||  in AliasVerifyPptp()
453 	    (ntohl(hptr->magic) != PPTP_MAGIC))  in AliasVerifyPptp()
475 		return (-1);  in AliasHandlePptpGreOut()
477 	lnk = FindPptpOutByPeerCallId(la, pip->ip_src, pip->ip_dst, gr->gh_call_id);  in AliasHandlePptpGreOut()
482 		DifferentialChecksum(&pip->ip_sum,  in AliasHandlePptpGreOut()
483 		    &alias_addr, &pip->ip_src, 2);  in AliasHandlePptpGreOut()
484 		pip->ip_src = alias_addr;  in AliasHandlePptpGreOut()
499 		return (-1);  in AliasHandlePptpGreIn()
501 	lnk = FindPptpInByPeerCallId(la, pip->ip_src, pip->ip_dst, gr->gh_call_id);  in AliasHandlePptpGreIn()
505 		/* De-alias the Peer's Call Id. */  in AliasHandlePptpGreIn()
506 		gr->gh_call_id = GetOriginalPort(lnk);  in AliasHandlePptpGreIn()
509 		DifferentialChecksum(&pip->ip_sum,  in AliasHandlePptpGreIn()
510 		    &src_addr, &pip->ip_dst, 2);  in AliasHandlePptpGreIn()
511 		pip->ip_dst = src_addr;  in AliasHandlePptpGreIn()