From: Alan T. DeKok <aland@freeradius.org>
Date: Sun, 10 May 2020 15:57:47 +0000 (-0400)
Subject: add fr_ip6_pesudo_header_checksum()
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8e0afda8fa066e463eaebf5f4d55b9e527dcb579;p=thirdparty%2Ffreeradius-server.git

add fr_ip6_pesudo_header_checksum()
---

diff --git a/src/lib/util/net.c b/src/lib/util/net.c
index e7082ea1c3b..a1ad92effb5 100644
--- a/src/lib/util/net.c
+++ b/src/lib/util/net.c
@@ -162,3 +162,23 @@ uint16_t fr_ip_header_checksum(uint8_t const *data, uint8_t ihl)
 	sum += (sum >> 16);
 	return ((uint16_t) ~sum);
 }
+
+uint16_t fr_ip6_pesudo_header_checksum(struct in6_addr *src, struct in6_addr *dst, uint16_t ip_len, uint8_t ip_next)
+{
+	uint64_t sum = 0;
+	ip_pseudo_header6_t ip6;
+	uint16_t const *p = (uint16_t const *) &ip6;
+	int8_t nwords = sizeof(ip6) >> 1; /* number of 16-bit words */
+
+	memcpy(&ip6.ip_src, src, sizeof(ip6.ip_src));
+	memcpy(&ip6.ip_dst, dst, sizeof(ip6.ip_dst));
+	ip6.ip_len = ip_len;
+	ip6.ip_next = ip_next;
+
+	for (sum = 0; nwords > 0; nwords--) {
+		sum += *p++;
+	}
+	sum = (sum >> 16) + (sum & 0xffff);
+	sum += (sum >> 16);
+	return ((uint16_t) ~sum);
+}
diff --git a/src/lib/util/net.h b/src/lib/util/net.h
index cccd4ff37db..deca823f28d 100644
--- a/src/lib/util/net.h
+++ b/src/lib/util/net.h
@@ -125,6 +125,12 @@ typedef struct CC_HINT(__packed__) {
 	struct in6_addr ip_src, ip_dst;	//!< Src and Dst address
 } ip_header6_t;
 
+typedef struct CC_HINT(__packed__) {
+	struct in6_addr ip_src, ip_dst;	//!< Src and Dst address
+	uint32_t	ip_len;		//!< length
+	uint32_t	ip_next;	//!< upper 24 bits must be zero
+} ip_pseudo_header6_t;
+
 /*
  *	UDP protocol header.
  *	Per RFC 768, September, 1981.
@@ -147,6 +153,7 @@ uint16_t	fr_udp_checksum(uint8_t const *data, uint16_t len, uint16_t checksum,
 			 	struct in_addr const src_addr, struct in_addr const dst_addr);
 int		fr_udp_header_check(uint8_t const *data, uint16_t remaining, ip_header_t const *ip);
 uint16_t	fr_ip_header_checksum(uint8_t const *data, uint8_t ihl);
+uint16_t	fr_ip6_pesudo_header_checksum(struct in6_addr *src, struct in6_addr *dst, uint16_t ip_len, uint8_t ip_next);
 
 /** Write out an unsigned 16bit integer in wire format (big endian)
  *