Fix unit tests for Nitro attester.

cmd/veil/main_test.go

@@ -221,6 +221,11 @@ func TestReadyHandler(t *testing.T) {
 func TestAttestation(t *testing.T) {
 	defer stopSvc(startSvc(t, withFlags()))
 
+	var attester enclave.Attester = enclave.NewNitroAttester()
+	if !enclave.IsEnclave() {
+		attester = enclave.NewNoopAttester()
+	}
+
 	cases := []struct {
 		name     string
 		url      string
@@ -261,7 +266,7 @@ func TestAttestation(t *testing.T) {
 			require.NoError(t, json.Unmarshal(body, &a))
 
 			// "Verify" the attestation document using our noop attester.
-			aux, err := enclave.NewNoopAttester().Verify(&a, c.nonce)
+			aux, err := attester.Verify(&a, c.nonce)
 			require.NoError(t, err, errFromBody(t, resp))
 
 			// Ensure that the recovered nonce matches what we sent.

internal/nonce/nonce.go

@@ -4,6 +4,7 @@ import (
 	"crypto/rand"
 	"encoding/base64"
 	"errors"
+	"fmt"
 	"net/url"
 
 	"github.com/Amnesic-Systems/veil/internal/errs"
@@ -47,8 +48,9 @@ func New() (*Nonce, error) {
 
 // FromSlice turns a byte slice into a nonce.
 func FromSlice(s []byte) (*Nonce, error) {
-	if len(s) != Len {
-		return nil, errs.InvalidLength
+	if len(s) < Len {
+		return nil, fmt.Errorf("%w: slice len is %d but need at least %d",
+			errs.InvalidLength, len(s), Len)
 	}
 
 	var n Nonce

internal/nonce/nonce_test.go

@@ -25,9 +25,9 @@ func TestFromSlice(t *testing.T) {
 			wantErr: errs.InvalidLength,
 		},
 		{
-			name:    "too long",
-			in:      append(validSlice, 0),
-			wantErr: errs.InvalidLength,
+			name: "too long",
+			in:   append(validSlice, 0),
+			want: Nonce{1},
 		},
 		{
 			name:    "valid",