Import in_cksum_phdr() and in_cksum_addword() from NetBSD.

1 files changed, 48 insertions, 1 deletions

diff --git a/sys/netinet/in.h b/sys/netinet/in.h
index 25dcd58b73a..2c91f6673dd 100644
--- a/sys/netinet/in.h
+++ b/sys/netinet/in.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: in.h,v 1.50 2001/06/24 23:33:55 angelos Exp $	*/
+/*	$OpenBSD: in.h,v 1.51 2001/06/24 23:41:47 angelos Exp $	*/
 /*	$NetBSD: in.h,v 1.20 1996/02/13 23:41:47 christos Exp $	*/
 
 /*
@@ -494,6 +494,53 @@ struct ip_mreq {
 
 #include <sys/cdefs.h>
 
+/*
+ * in_cksum_phdr:
+ *
+ *	Compute significant parts of the IPv4 checksum pseudo-header
+ *	for use in a delayed TCP/UDP checksum calculation.
+ *
+ *	Args:
+ *
+ *		src		Source IP address
+ *		dst		Destination IP address
+ *		lenproto	htons(proto-hdr-len + proto-number)
+ */
+static __inline u_int16_t __attribute__((__unused__))
+in_cksum_phdr(u_int32_t src, u_int32_t dst, u_int32_t lenproto)
+{
+	u_int32_t sum;
+
+	sum = lenproto +
+	      (u_int16_t)(src >> 16) +
+	      (u_int16_t)(src /*& 0xffff*/) +
+	      (u_int16_t)(dst >> 16) +
+	      (u_int16_t)(dst /*& 0xffff*/);
+
+	sum = (u_int16_t)(sum >> 16) + (u_int16_t)(sum /*& 0xffff*/);
+
+	if (sum > 0xffff)
+		sum -= 0xffff;
+
+	return (sum);
+}
+
+/*
+ * in_cksum_addword:
+ *
+ *	Add the two 16-bit network-order values, carry, and return.
+ */
+static __inline u_int16_t __attribute__((__unused__))
+in_cksum_addword(u_int16_t a, u_int16_t b)
+{
+	u_int32_t sum = a + b;
+
+	if (sum > 0xffff)
+		sum -= 0xffff;
+
+	return (sum);
+}
+
 __BEGIN_DECLS
 int	   bindresvport __P((int, struct sockaddr_in *));
 struct sockaddr;