Slightly refactored error messages

[gogost.git] / gost28147 / mac.go

diff --git a/gost28147/mac.go b/gost28147/mac.go
index a5a048749767c222f986fb3517f8e97cdc140b07..71e80397fdb3e53f7d3e5895fd33049a7bb5ca7c 100644 (file)
--- a/gost28147/mac.go
+++ b/gost28147/mac.go
@@ -16,7 +16,7 @@
 package gost28147
 
 import (
-       "errors"
+       "fmt"
 )
 
 var (
@@ -42,10 +42,10 @@ type MAC struct {
 // following ones are fed to Write function.
 func (c *Cipher) NewMAC(size int, iv []byte) (*MAC, error) {
        if size == 0 || size > 8 {
-               return nil, errors.New("gogost/gost28147: invalid tag size")
+               return nil, fmt.Errorf("gogost/gost28147: invalid tag size (0<%d<=8)", size)
        }
        if len(iv) != BlockSize {
-               return nil, errors.New("gogost/gost28147: len(iv) != 8")
+               return nil, fmt.Errorf("gogost/gost28147: len(iv)=%d != %d", len(iv), BlockSize)
        }
        m := MAC{c: c, size: size, iv: iv}
        n2, n1 := block2nvs(iv)