diff --git a/src/proto/sha256.pro b/src/proto/sha256.pro
index 3c4d975..464b354 100644
--- a/src/proto/sha256.pro
+++ b/src/proto/sha256.pro
@@ -2,6 +2,7 @@
 void sha256_start __ARGS((context_sha256_T *ctx));
 void sha256_update __ARGS((context_sha256_T *ctx, char_u *input, UINT32_T length));
 void sha256_finish __ARGS((context_sha256_T *ctx, char_u digest[32]));
+char_u *sha256_bytes __ARGS((char_u *buf, int buf_len, char_u *salt, int salt_len));
 char_u *sha256_key __ARGS((char_u *buf, char_u *salt, int salt_len));
 int sha256_self_test __ARGS((void));
 void sha2_seed __ARGS((char_u *header, int header_len, char_u *salt, int salt_len));