Fix RA profile deployability issue (#8002)

If validation profiles haven't been explicitly configured, use the
default profile for all incoming requests regardless of which profile
they specify.

Fixes https://github.com/letsencrypt/boulder/issues/7605

ra/ra.go

@@ -391,6 +391,9 @@ func NewValidationProfiles(defaultName string, configs map[string]ValidationProf
 }
 
 func (vp *validationProfiles) get(name string) (*validationProfile, error) {
+	if vp.defaultName == UnconfiguredDefaultProfileName {
+		return vp.byName[vp.defaultName], nil
+	}
 	if name == "" {
 		name = vp.defaultName
 	}

ra/ra_test.go

@@ -1763,6 +1763,67 @@ func TestNewOrder_ValidationProfiles(t *testing.T) {
 	}
 }
 
+func TestNewOrder_UnconfiguredValidationProfiles(t *testing.T) {
+	_, _, ra, _, _, cleanUp := initAuthorities(t)
+	defer cleanUp()
+
+	ra.profiles = &validationProfiles{
+		defaultName: UnconfiguredDefaultProfileName,
+		byName: map[string]*validationProfile{
+			UnconfiguredDefaultProfileName: {
+				pendingAuthzLifetime: 1 * 24 * time.Hour,
+				validAuthzLifetime:   1 * 24 * time.Hour,
+				orderLifetime:        1 * 24 * time.Hour,
+			},
+		},
+	}
+
+	for _, tc := range []struct {
+		name        string
+		profile     string
+		wantExpires time.Time
+	}{
+		{
+			// A request with no profile should get an order and authzs with one-day lifetimes.
+			name:        "no profile specified",
+			profile:     "",
+			wantExpires: ra.clk.Now().Add(1 * 24 * time.Hour),
+		},
+		{
+			// A request for a specific profile should get the same lifetimes.
+			name:        "profile specified",
+			profile:     "test",
+			wantExpires: ra.clk.Now().Add(1 * 24 * time.Hour),
+		},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			order, err := ra.NewOrder(context.Background(), &rapb.NewOrderRequest{
+				RegistrationID:         Registration.Id,
+				DnsNames:               []string{randomDomain()},
+				CertificateProfileName: tc.profile,
+			})
+			if err != nil {
+				t.Fatalf("creating order: %s", err)
+			}
+			gotExpires := order.Expires.AsTime()
+			if gotExpires != tc.wantExpires {
+				t.Errorf("NewOrder(profile: %q).Expires = %s, expected %s", tc.profile, gotExpires, tc.wantExpires)
+			}
+
+			authz, err := ra.GetAuthorization(context.Background(), &rapb.GetAuthorizationRequest{
+				Id: order.V2Authorizations[0],
+			})
+			if err != nil {
+				t.Fatalf("fetching test authz: %s", err)
+			}
+			gotExpires = authz.Expires.AsTime()
+			if gotExpires != tc.wantExpires {
+				t.Errorf("GetAuthorization(profile: %q).Expires = %s, expected %s", tc.profile, gotExpires, tc.wantExpires)
+			}
+		})
+	}
+}
+
 func TestNewOrder_ProfileSelectionAllowList(t *testing.T) {
 	_, _, ra, _, _, cleanUp := initAuthorities(t)
 	defer cleanUp()