From 1224206f400da2d34e813bbc113f929acd5e8aa9 Mon Sep 17 00:00:00 2001
From: "[anp/hsw]" <sysop@880.ru>
Date: Fri, 16 Aug 2024 00:07:38 +0700
Subject: [PATCH] fixing -Wstrict-aliasing (part 1)

---
 tpws/helpers.c | 2 +-
 tpws/helpers.h | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/tpws/helpers.c b/tpws/helpers.c
index 08ec98f..0c6e24b 100644
--- a/tpws/helpers.c
+++ b/tpws/helpers.c
@@ -155,7 +155,7 @@ bool saconvmapped(struct sockaddr_storage *a)
 {
 	if ((a->ss_family == AF_INET6) && saismapped((struct sockaddr_in6*)a))
 	{
-		uint32_t ip4 = *(uint32_t*)(((struct sockaddr_in6*)a)->sin6_addr.s6_addr+12);
+		uint32_t ip4 = IN6_EXTRACT_MAP4(((struct sockaddr_in6*)a)->sin6_addr.s6_addr);
 		uint16_t port = ((struct sockaddr_in6*)a)->sin6_port;
 		a->ss_family = AF_INET;
 		((struct sockaddr_in*)a)->sin_addr.s_addr = ip4;
diff --git a/tpws/helpers.h b/tpws/helpers.h
index 1989a14..f1383cb 100644
--- a/tpws/helpers.h
+++ b/tpws/helpers.h
@@ -59,3 +59,12 @@ bool pf_parse(const char *s, port_filter *pf);
 #ifndef IN_LOOPBACK
 #define IN_LOOPBACK(a)          ((((uint32_t) (a)) & 0xff000000) == 0x7f000000)
 #endif
+
+#ifdef __GNUC__
+#define IN6_EXTRACT_MAP4(a) \
+  (__extension__                                                              \
+   ({ const struct in6_addr *__a = (const struct in6_addr *) (a);             \
+      (((const uint32_t *) (__a))[3]); }))
+#else
+#define IN6_EXTRACT_MAP4(a)	(((const uint32_t *) (a))[3])
+#endif