Merge pull request #219 from ebiggers/improve-errors

Improve error messages and suggestions

4 files changed, 12 insertions, 17 deletions

diff --git a/crypto/crypto.go b/crypto/crypto.go
index 9a138d0..1f64b38 100644
--- a/crypto/crypto.go
+++ b/crypto/crypto.go
@@ -50,13 +50,9 @@ import (
 
 // Crypto error values
 var (
-	ErrBadAuth        = errors.New("key authentication check failed")
-	ErrNegativeLength = errors.New("keys cannot have negative lengths")
-	ErrRecoveryCode   = errors.New("invalid recovery code")
-	ErrGetrandomFail  = util.SystemError("getrandom() failed")
-	ErrKeyAlloc       = util.SystemError("could not allocate memory for key")
-	ErrKeyFree        = util.SystemError("could not free memory of key")
-	ErrKeyLock        = errors.New("could not lock key in memory")
+	ErrBadAuth      = errors.New("key authentication check failed")
+	ErrRecoveryCode = errors.New("invalid recovery code")
+	ErrMlockUlimit  = errors.New("could not lock key in memory")
 )
 
 // panicInputLength panics if "name" has invalid length (expected != actual)
diff --git a/crypto/crypto_test.go b/crypto/crypto_test.go
index 6eb0b02..10b3d17 100644
--- a/crypto/crypto_test.go
+++ b/crypto/crypto_test.go
@@ -257,7 +257,7 @@ func TestBigKeyGen(t *testing.T) {
 	case nil:
 		key.Wipe()
 		return
-	case ErrKeyLock:
+	case ErrMlockUlimit:
 		// Don't fail just because "ulimit -l" is too low.
 		return
 	default:
diff --git a/crypto/key.go b/crypto/key.go
index 77adc95..2e57443 100644
--- a/crypto/key.go
+++ b/crypto/key.go
@@ -98,7 +98,7 @@ func NewBlankKey(length int) (*Key, error) {
 	if length == 0 {
 		return &Key{data: nil}, nil
 	} else if length < 0 {
-		return nil, errors.Wrapf(ErrNegativeLength, "length of %d requested", length)
+		return nil, errors.Errorf("requested key length %d is negative", length)
 	}
 
 	flags := keyMmapFlags
@@ -109,11 +109,11 @@ func NewBlankKey(length int) (*Key, error) {
 	// See MAP_ANONYMOUS in http://man7.org/linux/man-pages/man2/mmap.2.html
 	data, err := unix.Mmap(-1, 0, length, keyProtection, flags)
 	if err == unix.EAGAIN {
-		return nil, ErrKeyLock
+		return nil, ErrMlockUlimit
 	}
 	if err != nil {
-		log.Printf("unix.Mmap() with length=%d failed: %v", length, err)
-		return nil, ErrKeyAlloc
+		return nil, errors.Wrapf(err,
+			"failed to allocate (mmap) key buffer of length %d", length)
 	}
 
 	key := &Key{data: data}
@@ -139,7 +139,7 @@ func (key *Key) Wipe() error {
 
 		if err := unix.Munmap(data); err != nil {
 			log.Printf("unix.Munmap() failed: %v", err)
-			return ErrKeyFree
+			return errors.Wrapf(err, "failed to free (munmap) key buffer")
 		}
 	}
 	return nil
diff --git a/crypto/rand.go b/crypto/rand.go
index 4d8c044..7d1e55b 100644
--- a/crypto/rand.go
+++ b/crypto/rand.go
@@ -90,10 +90,9 @@ func (r randReader) Read(buffer []byte) (int, error) {
 	case nil:
 		return n, nil
 	case unix.EAGAIN:
-		return 0, errors.Wrap(ErrGetrandomFail, "insufficient entropy in pool")
+		err = errors.New("insufficient entropy in pool")
 	case unix.ENOSYS:
-		return 0, errors.Wrap(ErrGetrandomFail, "kernel must be v3.17 or later")
-	default:
-		return 0, errors.Wrap(ErrGetrandomFail, err.Error())
+		err = errors.New("kernel must be v3.17 or later")
 	}
+	return 0, errors.Wrap(err, "getrandom() failed")
 }