pf: merge pf_scrub_ip() and pf_scrub_ip6()

Merge pf_scrub_ip() and pf_scrub_ip6() into a single function.  Call
pf_scrub with the right arugments in the rule case so that match
rules will work as expected.

OK henning@

Obtained from:	OpenBSD, claudio <claudio@openbsd.org>, 48c45e6969
Sponsored by:	Rubicon Communications, LLC ("Netgate")
Differential Revision:	https://reviews.freebsd.org/D46597

3 files changed, 36 insertions, 37 deletions

diff --git a/sys/net/pfvar.h b/sys/net/pfvar.h
index 0dfa58979f16..61752a146b57 100644
--- a/sys/net/pfvar.h
+++ b/sys/net/pfvar.h
@@ -2642,12 +2642,9 @@ void			 pf_rule_to_actions(struct pf_krule *,
 			    struct pf_rule_actions *);
 int			 pf_normalize_mss(struct mbuf *m, int off,
 			    struct pf_pdesc *pd);
-#ifdef INET
-void	pf_scrub_ip(struct mbuf *, struct pf_pdesc *);
-#endif	/* INET */
-#ifdef INET6
-void	pf_scrub_ip6(struct mbuf *, struct pf_pdesc *);
-#endif	/* INET6 */
+#if defined(INET) || defined(INET6)
+void	pf_scrub(struct mbuf *, struct pf_pdesc *);
+#endif
 
 struct pfi_kkif		*pf_kkif_create(int);
 void			 pf_kkif_free(struct pfi_kkif *);
diff --git a/sys/netpfil/pf/pf.c b/sys/netpfil/pf/pf.c
index d4adf1363cdf..456fdd0aa9bd 100644
--- a/sys/netpfil/pf/pf.c
+++ b/sys/netpfil/pf/pf.c
@@ -9221,7 +9221,7 @@ done:
 		REASON_SET(&reason, PFRES_MEMORY);
 	}
 
-	pf_scrub_ip(m, &pd);
+	pf_scrub(m, &pd);
 	if (pd.proto == IPPROTO_TCP && pd.act.max_mss)
 		pf_normalize_mss(m, off, &pd);
 
@@ -9676,7 +9676,7 @@ done:
 		REASON_SET(&reason, PFRES_MEMORY);
 	}
 
-	pf_scrub_ip6(m, &pd);
+	pf_scrub(m, &pd);
 	if (pd.proto == IPPROTO_TCP && pd.act.max_mss)
 		pf_normalize_mss(m, off, &pd);
 
diff --git a/sys/netpfil/pf/pf_norm.c b/sys/netpfil/pf/pf_norm.c
index 284660767224..926529330619 100644
--- a/sys/netpfil/pf/pf_norm.c
+++ b/sys/netpfil/pf/pf_norm.c
@@ -2267,14 +2267,20 @@ sctp_drop:
 	return (PF_DROP);
 }
 
-#ifdef INET
+#if defined(INET) || defined(INET6)
 void
-pf_scrub_ip(struct mbuf *m, struct pf_pdesc *pd)
+pf_scrub(struct mbuf *m, struct pf_pdesc *pd)
 {
+
 	struct ip		*h = mtod(m, struct ip *);
+#ifdef INET6
+	struct ip6_hdr		*h6 = mtod(m, struct ip6_hdr *);
+#endif
 
 	/* Clear IP_DF if no-df was requested */
-	if (pd->act.flags & PFSTATE_NODF && h->ip_off & htons(IP_DF)) {
+	if (pd->af == AF_INET && pd->act.flags & PFSTATE_NODF &&
+	    h->ip_off & htons(IP_DF))
+	{
 		u_int16_t ip_off = h->ip_off;
 
 		h->ip_off &= htons(~IP_DF);
@@ -2282,48 +2288,44 @@ pf_scrub_ip(struct mbuf *m, struct pf_pdesc *pd)
 	}
 
 	/* Enforce a minimum ttl, may cause endless packet loops */
-	if (pd->act.min_ttl && h->ip_ttl < pd->act.min_ttl) {
+	if (pd->af == AF_INET && pd->act.min_ttl &&
+	    h->ip_ttl < pd->act.min_ttl) {
 		u_int16_t ip_ttl = h->ip_ttl;
 
 		h->ip_ttl = pd->act.min_ttl;
 		h->ip_sum = pf_cksum_fixup(h->ip_sum, ip_ttl, h->ip_ttl, 0);
 	}
-
+#ifdef INET6
+	/* Enforce a minimum ttl, may cause endless packet loops */
+	if (pd->af == AF_INET6 && pd->act.min_ttl &&
+	    h6->ip6_hlim < pd->act.min_ttl)
+		h6->ip6_hlim = pd->act.min_ttl;
+#endif
 	/* Enforce tos */
 	if (pd->act.flags & PFSTATE_SETTOS) {
-		u_int16_t	ov, nv;
+		if (pd->af == AF_INET) {
+			u_int16_t	ov, nv;
 
-		ov = *(u_int16_t *)h;
-		h->ip_tos = pd->act.set_tos | (h->ip_tos & IPTOS_ECN_MASK);
-		nv = *(u_int16_t *)h;
+			ov = *(u_int16_t *)h;
+			h->ip_tos = pd->act.set_tos | (h->ip_tos & IPTOS_ECN_MASK);
+			nv = *(u_int16_t *)h;
 
-		h->ip_sum = pf_cksum_fixup(h->ip_sum, ov, nv, 0);
+			h->ip_sum = pf_cksum_fixup(h->ip_sum, ov, nv, 0);
+#ifdef INET6
+		} else if (pd->af == AF_INET6) {
+			h6->ip6_flow &= IPV6_FLOWLABEL_MASK | IPV6_VERSION_MASK;
+			h6->ip6_flow |= htonl((pd->act.set_tos | IPV6_ECN(h6)) << 20);
+#endif
+		}
 	}
 
 	/* random-id, but not for fragments */
-	if (pd->act.flags & PFSTATE_RANDOMID && !(h->ip_off & ~htons(IP_DF))) {
+	if (pd->af == AF_INET &&
+	    pd->act.flags & PFSTATE_RANDOMID && !(h->ip_off & ~htons(IP_DF))) {
 		uint16_t ip_id = h->ip_id;
 
 		ip_fillid(h);
 		h->ip_sum = pf_cksum_fixup(h->ip_sum, ip_id, h->ip_id, 0);
 	}
 }
-#endif /* INET */
-
-#ifdef INET6
-void
-pf_scrub_ip6(struct mbuf *m, struct pf_pdesc *pd)
-{
-	struct ip6_hdr		*h = mtod(m, struct ip6_hdr *);
-
-	/* Enforce a minimum ttl, may cause endless packet loops */
-	if (pd->act.min_ttl && h->ip6_hlim < pd->act.min_ttl)
-		h->ip6_hlim = pd->act.min_ttl;
-
-	/* Enforce tos. Set traffic class bits */
-	if (pd->act.flags & PFSTATE_SETTOS) {
-		h->ip6_flow &= IPV6_FLOWLABEL_MASK | IPV6_VERSION_MASK;
-		h->ip6_flow |= htonl((pd->act.set_tos | IPV6_ECN(h)) << 20);
-	}
-}
 #endif