diff --git a/configure.ac b/configure.ac
index 97e4ee577..4e0539fa2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2008,7 +2008,6 @@ AC_CHECK_FUNCS([ \
 	strtoll \
 	strtoul \
 	strtoull \
-	swap32 \
 	sysconf \
 	tcgetpgrp \
 	timegm \
diff --git a/defines.h b/defines.h
index ed860e78b..b02f2942a 100644
--- a/defines.h
+++ b/defines.h
@@ -646,6 +646,32 @@ struct winsize {
 # endif /* WORDS_BIGENDIAN */
 #endif /* BYTE_ORDER */
 
+#ifndef HAVE_ENDIAN_H
+# define openssh_swap32(v)					\
+	(uint32_t)(((uint32_t)(v) & 0xff) << 24 |		\
+	((uint32_t)(v) & 0xff00) << 8 |				\
+	((uint32_t)(v) & 0xff0000) >> 8 |			\
+	((uint32_t)(v) & 0xff000000) >> 24)
+# define openssh_swap64(v)					\
+	(__uint64_t)((((__uint64_t)(v) & 0xff) << 56) |		\
+	((__uint64_t)(v) & 0xff00ULL) << 40 |			\
+	((__uint64_t)(v) & 0xff0000ULL) << 24 |			\
+	((__uint64_t)(v) & 0xff000000ULL) << 8 |		\
+	((__uint64_t)(v) & 0xff00000000ULL) >> 8 |		\
+	((__uint64_t)(v) & 0xff0000000000ULL) >> 24 |		\
+	((__uint64_t)(v) & 0xff000000000000ULL) >> 40 |		\
+	((__uint64_t)(v) & 0xff00000000000000ULL) >> 56)
+# ifdef WORDS_BIGENDIAN
+#  define le32toh(v) (openssh_swap32(v))
+#  define le64toh(v) (openssh_swap64(v))
+#  define htole64(v) (openssh_swap64(v))
+# else
+#  define le32toh(v) ((uint32_t)v)
+#  define le64toh(v) ((uint64_t)v)
+#  define htole64(v) ((uint64_t)v)
+# endif
+#endif
+
 /* Function replacement / compatibility hacks */
 
 #if !defined(HAVE_GETADDRINFO) && (defined(HAVE_OGETADDRINFO) || defined(HAVE_NGETADDRINFO))