added a simple mock signer

1 files changed, 23 insertions, 0 deletions

diff --git a/mocks/crypto.go b/mocks/crypto.go
new file mode 100644
index 0000000..87c883a
--- /dev/null
+++ b/mocks/crypto.go
@@ -0,0 +1,23 @@
+package mocks
+
+import (
+	"crypto"
+	"crypto/ed25519"
+	"io"
+)
+
+// TestSign implements the signer interface.  It can be used to mock an Ed25519
+// signer that always return the same public key, signature, and error.
+type TestSigner struct {
+	PublicKey *[ed25519.PublicKeySize]byte
+	Signature *[ed25519.SignatureSize]byte
+	Error     error
+}
+
+func (ts *TestSigner) Public() crypto.PublicKey {
+	return ed25519.PublicKey(ts.PublicKey[:])
+}
+
+func (ts *TestSigner) Sign(rand io.Reader, digest []byte, opts crypto.SignerOpts) ([]byte, error) {
+	return ts.Signature[:], ts.Error
+}