diff --git a/src/libsodium/include/sodium/utils.h b/src/libsodium/include/sodium/utils.h
index aaf3fc5d..bd34649a 100644
--- a/src/libsodium/include/sodium/utils.h
+++ b/src/libsodium/include/sodium/utils.h
@@ -35,6 +35,12 @@ int sodium_hex2bin(unsigned char * const bin, const size_t bin_maxlen,
                    const char * const ignore, size_t * const bin_len,
                    const char ** const hex_end);
 
+SODIUM_EXPORT
+int sodium_mlock(const void *addr, const size_t len);
+
+SODIUM_EXPORT
+int sodium_munlock(const void *addr, const size_t len);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/libsodium/sodium/utils.c b/src/libsodium/sodium/utils.c
index 75e74b08..fdf16390 100644
--- a/src/libsodium/sodium/utils.c
+++ b/src/libsodium/sodium/utils.c
@@ -9,6 +9,10 @@
 #include <stdlib.h>
 #include <string.h>
 
+#ifdef HAVE_SYS_MMAN_H
+# include <sys/mman.h>
+#endif
+
 #include "utils.h"
 #include "randombytes.h"
 #ifdef _WIN32
@@ -152,3 +156,29 @@ sodium_hex2bin(unsigned char * const bin, const size_t bin_maxlen,
     }
     return ret;
 }
+
+int
+sodium_mlock(const void *addr, const size_t len)
+{
+#ifdef HAVE_MLOCK
+    return mlock(addr, len);
+#elif defined(HAVE_VIRTUALLOCK)
+    return -(VirtualLock(addr, len) != 0);
+#else
+    errno = ENOSYS;
+    return -1;
+#endif
+}
+
+int
+sodium_munlock(const void *addr, const size_t len)
+{
+#ifdef HAVE_MLOCK
+    return munlock(addr, len);
+#elif defined(HAVE_VIRTUALLOCK)
+    return -(VirtualUnlock(addr, len) != 0);
+#else
+    errno = ENOSYS;
+    return -1;
+#endif
+}