From 0da228c57cab11fe36a8101f24c39a0120a6f226 Mon Sep 17 00:00:00 2001
From: Robert Lubos <robert.lubos@nordicsemi.no>
Date: Mon, 4 Oct 2021 13:16:19 +0200
Subject: [PATCH] net: ip: Verify that in_addr/in6_addr struct sizes are
 correct

Make sure that in_addr/in6_addr structure size match the respective
binary IP address size with BUILD_ASSERT.

Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
---
 include/net/net_ip.h | 6 ++++++
 subsys/net/ip/ipv4.c | 2 ++
 subsys/net/ip/ipv6.c | 2 ++
 3 files changed, 10 insertions(+)

diff --git a/include/net/net_ip.h b/include/net/net_ip.h
index d07e02880b4..66805675c71 100644
--- a/include/net/net_ip.h
+++ b/include/net/net_ip.h
@@ -144,6 +144,9 @@ struct in6_addr {
 	};
 };
 
+/* Binary size of the IPv6 address */
+#define NET_IPV6_ADDR_SIZE 16
+
 /** IPv4 address struct */
 struct in_addr {
 	union {
@@ -154,6 +157,9 @@ struct in_addr {
 	};
 };
 
+/* Binary size of the IPv4 address */
+#define NET_IPV4_ADDR_SIZE 4
+
 /** Socket address family type */
 typedef unsigned short int sa_family_t;
 
diff --git a/subsys/net/ip/ipv4.c b/subsys/net/ip/ipv4.c
index c978253ecae..308cc50e043 100644
--- a/subsys/net/ip/ipv4.c
+++ b/subsys/net/ip/ipv4.c
@@ -25,6 +25,8 @@ LOG_MODULE_REGISTER(net_ipv4, CONFIG_NET_IPV4_LOG_LEVEL);
 #include "tcp_internal.h"
 #include "ipv4.h"
 
+BUILD_ASSERT(sizeof(struct in_addr) == NET_IPV4_ADDR_SIZE);
+
 /* Timeout for various buffer allocations in this file. */
 #define NET_BUF_TIMEOUT K_MSEC(50)
 
diff --git a/subsys/net/ip/ipv6.c b/subsys/net/ip/ipv6.c
index 7afc293c969..b9e32a43b50 100644
--- a/subsys/net/ip/ipv6.c
+++ b/subsys/net/ip/ipv6.c
@@ -35,6 +35,8 @@ LOG_MODULE_REGISTER(net_ipv6, CONFIG_NET_IPV6_LOG_LEVEL);
 #include "route.h"
 #include "net_stats.h"
 
+BUILD_ASSERT(sizeof(struct in6_addr) == NET_IPV6_ADDR_SIZE);
+
 /* Timeout value to be used when allocating net buffer during various
  * neighbor discovery procedures.
  */