checking in prelim stuff

kdf/errs.go

@@ -0,0 +1,14 @@
+package kdf
+
+import (
+	"errors"
+)
+
+var (
+	ErrBadData    error = errors.New("unable to cast data into buffer for KDF")
+	ErrNoKeyLen   error = errors.New("no key length configured or bad key length for KDF")
+	ErrNoRounds   error = errors.New("no rounds number configured or bad number of rounds for KDF")
+	ErrNoSalt     error = errors.New("no salt configured or bad salt value for KDF")
+	ErrNoSecret   error = errors.New("no secret configured or bad secret value for KDF")
+	ErrUnknownKdf error = errors.New("unable to determine matching KDF")
+)