Factor out ip6_deletefraghdr() function, to be shared between IPv6

stack and pf(4).

Submitted by:	Kristof Provost
Reviewed by:	ae
Differential Revision:	D1764

3 files changed, 33 insertions, 19 deletions

diff --git a/sys/netinet6/frag6.c b/sys/netinet6/frag6.c
index 92d07155bcb9..91818b2db62a 100644
--- a/sys/netinet6/frag6.c
+++ b/sys/netinet6/frag6.c
@@ -541,27 +541,16 @@ insert:
 	*q6->ip6q_nxtp = (u_char)(nxt & 0xff);
 #endif
 
-	/* Delete frag6 header */
-	if (m->m_len >= offset + sizeof(struct ip6_frag)) {
-		/* This is the only possible case with !PULLDOWN_TEST */
-		ovbcopy((caddr_t)ip6, (caddr_t)ip6 + sizeof(struct ip6_frag),
-		    offset);
-		m->m_data += sizeof(struct ip6_frag);
-		m->m_len -= sizeof(struct ip6_frag);
-	} else {
-		/* this comes with no copy if the boundary is on cluster */
-		if ((t = m_split(m, offset, M_NOWAIT)) == NULL) {
-			frag6_remque(q6);
-			V_frag6_nfrags -= q6->ip6q_nfrag;
+	if (ip6_deletefraghdr(m, offset, M_NOWAIT) != 0) {
+		frag6_remque(q6);
+		V_frag6_nfrags -= q6->ip6q_nfrag;
 #ifdef MAC
-			mac_ip6q_destroy(q6);
+		mac_ip6q_destroy(q6);
 #endif
-			free(q6, M_FTABLE);
-			V_frag6_nfragpackets--;
-			goto dropfrag;
-		}
-		m_adj(t, sizeof(struct ip6_frag));
-		m_cat(m, t);
+		free(q6, M_FTABLE);
+		V_frag6_nfragpackets--;
+
+		goto dropfrag;
 	}
 
 	/*
diff --git a/sys/netinet6/ip6_output.c b/sys/netinet6/ip6_output.c
index a3474d34dc35..dd7ef2cac6cb 100644
--- a/sys/netinet6/ip6_output.c
+++ b/sys/netinet6/ip6_output.c
@@ -1206,6 +1206,30 @@ ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen,
 	return (0);
 }
 
+int
+ip6_deletefraghdr(struct mbuf *m, int offset, int wait)
+{
+	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
+	struct mbuf *t;
+
+	/* Delete frag6 header. */
+	if (m->m_len >= offset + sizeof(struct ip6_frag)) {
+		/* This is the only possible case with !PULLDOWN_TEST. */
+		bcopy(ip6, (char *)ip6 + sizeof(struct ip6_frag),
+		    offset);
+		m->m_data += sizeof(struct ip6_frag);
+		m->m_len -= sizeof(struct ip6_frag);
+	} else {
+		/* This comes with no copy if the boundary is on cluster. */
+		if ((t = m_split(m, offset, wait)) == NULL)
+			return (ENOMEM);
+		m_adj(t, sizeof(struct ip6_frag));
+		m_cat(m, t);
+	}
+
+	return (0);
+}
+
 static int
 ip6_getpmtu(struct route_in6 *ro_pmtu, struct route_in6 *ro,
     struct ifnet *ifp, struct in6_addr *dst, u_long *mtup,
diff --git a/sys/netinet6/ip6_var.h b/sys/netinet6/ip6_var.h
index 155a607a7404..992a8acd1806 100644
--- a/sys/netinet6/ip6_var.h
+++ b/sys/netinet6/ip6_var.h
@@ -388,6 +388,7 @@ int	ip6_setpktopts(struct mbuf *, struct ip6_pktopts *,
 void	ip6_clearpktopts(struct ip6_pktopts *, int);
 struct ip6_pktopts *ip6_copypktopts(struct ip6_pktopts *, int);
 int	ip6_optlen(struct inpcb *);
+int	ip6_deletefraghdr(struct mbuf *, int, int);
 
 int	route6_input(struct mbuf **, int *, int);