4 files changed, 33 insertions, 13 deletions
diff --git a/src/include/common/hmac.h b/src/include/common/hmac.h
new file mode 100644
index 00000000000..ea0343a9da7
--- /dev/null
+++ b/src/include/common/hmac.h
@@ -0,0 +1,29 @@
+/*-------------------------------------------------------------------------
+ *
+ * hmac.h
+ *	  Generic headers for HMAC
+ *
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * IDENTIFICATION
+ *		  src/include/common/hmac.h
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#ifndef PG_HMAC_H
+#define PG_HMAC_H
+
+#include "common/cryptohash.h"
+
+/* opaque context, private to each HMAC implementation */
+typedef struct pg_hmac_ctx pg_hmac_ctx;
+
+extern pg_hmac_ctx *pg_hmac_create(pg_cryptohash_type type);
+extern int	pg_hmac_init(pg_hmac_ctx *ctx, const uint8 *key, size_t len);
+extern int	pg_hmac_update(pg_hmac_ctx *ctx, const uint8 *data, size_t len);
+extern int	pg_hmac_final(pg_hmac_ctx *ctx, uint8 *dest, size_t len);
+extern void pg_hmac_free(pg_hmac_ctx *ctx);
+
+#endif							/* PG_HMAC_H */
diff --git a/src/include/common/md5.h b/src/include/common/md5.h
index 6d100f5cfc2..62a31e6ed4e 100644
--- a/src/include/common/md5.h
+++ b/src/include/common/md5.h
@@ -18,6 +18,8 @@
 
 /* Size of result generated by MD5 computation */
 #define MD5_DIGEST_LENGTH 16
+/* Block size for MD5 */
+#define MD5_BLOCK_SIZE	64
 
 /* password-related data */
 #define MD5_PASSWD_CHARSET	"0123456789abcdef"
diff --git a/src/include/common/scram-common.h b/src/include/common/scram-common.h
index 9d684b41e8e..5777ce9fe33 100644
--- a/src/include/common/scram-common.h
+++ b/src/include/common/scram-common.h
@@ -46,19 +46,6 @@
  */
 #define SCRAM_DEFAULT_ITERATIONS	4096
 
-/*
- * Context data for HMAC used in SCRAM authentication.
- */
-typedef struct
-{
-	pg_cryptohash_ctx *sha256ctx;
-	uint8		k_opad[SHA256_HMAC_B];
-} scram_HMAC_ctx;
-
-extern int	scram_HMAC_init(scram_HMAC_ctx *ctx, const uint8 *key, int keylen);
-extern int	scram_HMAC_update(scram_HMAC_ctx *ctx, const char *str, int slen);
-extern int	scram_HMAC_final(uint8 *result, scram_HMAC_ctx *ctx);
-
 extern int	scram_SaltedPassword(const char *password, const char *salt,
 								 int saltlen, int iterations, uint8 *result);
 extern int	scram_H(const uint8 *str, int len, uint8 *result);
diff --git a/src/include/common/sha1.h b/src/include/common/sha1.h
index a61bc47deda..b1ee36f8eaf 100644
--- a/src/include/common/sha1.h
+++ b/src/include/common/sha1.h
@@ -15,5 +15,7 @@
 
 /* Size of result generated by SHA1 computation */
 #define SHA1_DIGEST_LENGTH 20
+/* Block size for SHA1 */
+#define SHA1_BLOCK_SIZE 64
 
 #endif							/* PG_SHA1_H */