diff --git a/sys/contrib/libb2/FREEBSD-Xlist b/sys/contrib/libb2/FREEBSD-Xlist
new file mode 100644
--- /dev/null
+++ b/sys/contrib/libb2/FREEBSD-Xlist
@@ -0,0 +1,11 @@
+.gitignore
+COPYING
+Makefile.am
+autogen.sh
+clean.sh
+configure.ac
+libb2.pc.in
+m4
+src/Makefile.am
+src/*-test.c
+src/blake2-kat.h
diff --git a/sys/contrib/libb2/FREEBSD-upgrade b/sys/contrib/libb2/FREEBSD-upgrade
new file mode 100755
--- /dev/null
+++ b/sys/contrib/libb2/FREEBSD-upgrade
@@ -0,0 +1,33 @@
+#!/bin/sh
+#
+# Usage: cd /usr/src/sys/contrib/libb2
+#        ./FREEBSD-upgrade <version>
+#
+# <version> should be in x.y.z format
+#
+
+set -e
+
+if [ ! -x "FREEBSD-upgrade" ] ; then
+  echo "Run from within src/sys/contrib/libb2/" >&2
+  exit 1
+fi
+
+if [ -z "$1" ]
+  then
+    echo "No version supplied" >&2
+    exit 1
+fi
+
+curl -LJO https://github.com/BLAKE2/libb2/archive/refs/tags/v$1.tar.gz
+
+tar -X FREEBSD-Xlist -xzf libb2-$1.tar.gz
+
+mv libb2-$1/src/* libb2-$1/
+
+rm -r libb2-$1/src
+
+mv libb2-$1/* .
+
+rm -r libb2-$1
+rm libb2-$1.tar.gz
diff --git a/sys/contrib/libb2/README.md b/sys/contrib/libb2/README.md
new file mode 100644
--- /dev/null
+++ b/sys/contrib/libb2/README.md
@@ -0,0 +1,14 @@
+# libb2
+
+C library providing BLAKE2b, BLAKE2s, BLAKE2bp, BLAKE2sp
+
+Installation:
+
+```
+$ ./autogen.sh
+$ ./configure
+$ make
+$ sudo make install
+```
+
+Contact: contact@blake2.net
diff --git a/sys/contrib/libb2/blake2-impl.h b/sys/contrib/libb2/blake2-impl.h
--- a/sys/contrib/libb2/blake2-impl.h
+++ b/sys/contrib/libb2/blake2-impl.h
@@ -14,6 +14,10 @@
 #ifndef __BLAKE2_IMPL_H__
 #define __BLAKE2_IMPL_H__
 
+#if defined(_WIN32) || defined(WIN32)
+#include <windows.h>
+#endif
+
 #include <stddef.h>
 #include <stdint.h>
 #include <string.h>
@@ -25,8 +29,10 @@
 
 static inline uint32_t load32( const void *src )
 {
-#if defined(NATIVE_LITTLE_ENDIAN) && !defined(HAVE_ALIGNED_ACCESS_REQUIRED)
-  return *( uint32_t * )( src );
+#if defined(NATIVE_LITTLE_ENDIAN)
+  uint32_t w;
+  memcpy( &w, src, sizeof( w ) );
+  return w;
 #else
   const uint8_t *p = ( uint8_t * )src;
   uint32_t w = *p++;
@@ -39,8 +45,10 @@
 
 static inline uint64_t load64( const void *src )
 {
-#if defined(NATIVE_LITTLE_ENDIAN) && !defined(HAVE_ALIGNED_ACCESS_REQUIRED)
-  return *( uint64_t * )( src );
+#if defined(NATIVE_LITTLE_ENDIAN)
+  uint64_t w;
+  memcpy( &w, src, sizeof( w ) );
+  return w;
 #else
   const uint8_t *p = ( uint8_t * )src;
   uint64_t w = *p++;
@@ -57,8 +65,8 @@
 
 static inline void store32( void *dst, uint32_t w )
 {
-#if defined(NATIVE_LITTLE_ENDIAN) && !defined(HAVE_ALIGNED_ACCESS_REQUIRED)
-  *( uint32_t * )( dst ) = w;
+#if defined(NATIVE_LITTLE_ENDIAN)
+  memcpy( dst, &w, sizeof( w ) );
 #else
   uint8_t *p = ( uint8_t * )dst;
   *p++ = ( uint8_t )w; w >>= 8;
@@ -70,8 +78,8 @@
 
 static inline void store64( void *dst, uint64_t w )
 {
-#if defined(NATIVE_LITTLE_ENDIAN) && !defined(HAVE_ALIGNED_ACCESS_REQUIRED)
-  *( uint64_t * )( dst ) = w;
+#if defined(NATIVE_LITTLE_ENDIAN)
+  memcpy( dst, &w, sizeof( w ) );
 #else
   uint8_t *p = ( uint8_t * )dst;
   *p++ = ( uint8_t )w; w >>= 8;