feat(sdk): MIC-1436: User can decrypt TDF files created with FileWatcher2.0.8 and older.

sdk/assertion.go

@@ -123,6 +123,41 @@ func (a Assertion) GetHash() ([]byte, error) {
 	return ocrypto.SHA256AsHex(transformedJSON), nil
 }
 
+func (s *Statement) UnmarshalJSON(data []byte) error {
+	// Define a custom struct for deserialization
+	type Alias Statement
+	aux := &struct {
+		Value json.RawMessage `json:"value,omitempty"`
+		*Alias
+	}{
+		Alias: (*Alias)(s),
+	}
+
+	if err := json.Unmarshal(data, &aux); err != nil {
+		return err
+	}
+
+	// Attempt to decode Value as an object
+	var temp map[string]interface{}
+	if json.Unmarshal(aux.Value, &temp) == nil {
+		// Re-encode the object as a string and assign to Value
+		objAsString, err := json.Marshal(temp)
+		if err != nil {
+			return err
+		}
+		s.Value = string(objAsString)
+	} else {
+		// Assign raw string to Value
+		var str string
+		if err := json.Unmarshal(aux.Value, &str); err != nil {
+			return fmt.Errorf("value is neither a valid JSON object nor a string: %s", string(aux.Value))
+		}
+		s.Value = str
+	}
+
+	return nil
+}
+
 // Statement includes information applying to the scope of the assertion.
 // It could contain rights, handling instructions, or general metadata.
 type Statement struct {

sdk/assertion_test.go

@@ -1,8 +1,10 @@
 package sdk
 
 import (
+	"encoding/json"
 	"testing"
 
+	"github.com/gowebpki/jcs"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -33,3 +35,150 @@ func TestTDFWithAssertion(t *testing.T) {
 
 	assert.Equal(t, "4a447a13c5a32730d20bdf7feecb9ffe16649bc731914b574d80035a3927f860", string(hashOfAssertion))
 }
+
+func TestTDFWithAssertionJsonObject(t *testing.T) {
+	// Define the assertion config with a JSON object in the statement value
+	value := `{
+		"ocl": {
+			"pol": "2ccf11cb-6c9a-4e49-9746-a7f0a295945d",
+			"cls": "SECRET",
+			"catl": [
+				{
+					"type": "P",
+					"name": "Releasable To",
+					"vals": ["usa"]
+				}
+			],
+			"dcr": "2024-12-17T13:00:52Z"
+		},
+		"context": {
+			"@base": "urn:nato:stanag:5636:A:1:elements:json"
+		}
+	}`
+	assertionConfig := AssertionConfig{
+		ID:             "ab43266781e64b51a4c52ffc44d6152c",
+		Type:           "handling",
+		Scope:          "payload",
+		AppliesToState: "", // Use "" or a pointer to a string if necessary
+		Statement: Statement{
+			Format: "json-structured",
+			Value:  value,
+		},
+	}
+
+	// Set up the assertion
+	assertion := Assertion{
+		ID:             assertionConfig.ID,
+		Type:           assertionConfig.Type,
+		Scope:          assertionConfig.Scope,
+		AppliesToState: assertionConfig.AppliesToState,
+		Statement:      assertionConfig.Statement,
+	}
+
+	var obj map[string]interface{}
+	err := json.Unmarshal([]byte(assertionConfig.Statement.Value), &obj)
+	require.NoError(t, err, "Unmarshaling the Value into a map should succeed")
+
+	ocl, ok := obj["ocl"].(map[string]interface{})
+	require.True(t, ok, "Parsed Value should contain 'ocl' as an object")
+	require.Equal(t, "SECRET", ocl["cls"], "'cls' field should match")
+	require.Equal(t, "2ccf11cb-6c9a-4e49-9746-a7f0a295945d", ocl["pol"], "'pol' field should match")
+
+	context, ok := obj["context"].(map[string]interface{})
+	require.True(t, ok, "Parsed Value should contain 'context' as an object")
+	require.Equal(t, "urn:nato:stanag:5636:A:1:elements:json", context["@base"], "'@base' field should match")
+
+	// Calculate the hash of the assertion
+	hashOfAssertion, err := assertion.GetHash()
+	require.NoError(t, err)
+
+	expectedHash := "722dd40a90a0f7ec718fb156207a647e64daa43c0ae1f033033473a172c72aee"
+	assert.Equal(t, expectedHash, string(hashOfAssertion))
+}
+
+func TestDeserializingAssertionWithJSONInStatementValue(t *testing.T) {
+	// the assertion has a JSON object in the statement value
+	assertionVal := ` {
+      "id": "bacbe31eab384df39d35a5fbe83778de",
+      "type": "handling",
+      "scope": "tdo",
+      "appliesToState": null,
+      "statement": {
+        "format": "json-structured",
+        "value": {
+          "ocl": {
+            "pol": "2ccf11cb-6c9a-4e49-9746-a7f0a295945d",
+            "cls": "SECRET",
+            "catl": [
+              {
+                "type": "P",
+                "name": "Releasable To",
+                "vals": [
+                  "usa"
+                ]
+              }
+            ],
+            "dcr": "2024-12-17T13:00:52Z"
+          },
+          "context": {
+            "@base": "urn:nato:stanag:5636:A:1:elements:json"
+          }
+        }
+      },
+      "binding": {
+        "method": "jws",
+        "signature": "eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9.eyJDb25maWRlbnRpYWxpdHlJbmZvcm1hdGlvbiI6InsgXCJvY2xcIjogeyBcInBvbFwiOiBcIjJjY2YxMWNiLTZjOWEtNGU0OS05NzQ2LWE3ZjBhMjk1OTQ1ZFwiLCBcImNsc1wiOiBcIlNFQ1JFVFwiLCBcImNhdGxcIjogWyB7IFwidHlwZVwiOiBcIlBcIiwgXCJuYW1lXCI6IFwiUmVsZWFzYWJsZSBUb1wiLCBcInZhbHNcIjogWyBcInVzYVwiIF0gfSBdLCBcImRjclwiOiBcIjIwMjQtMTItMTdUMTM6MDA6NTJaXCIgfSwgXCJjb250ZXh0XCI6IHsgXCJAYmFzZVwiOiBcInVybjpuYXRvOnN0YW5hZzo1NjM2OkE6MTplbGVtZW50czpqc29uXCIgfSB9In0.LlOzRLKKXMAqXDNsx9Ha5915CGcAkNLuBfI7jJmx6CnfQrLXhlRHWW3_aLv5DPsKQC6vh9gDQBH19o7q7EcukvK4IabA4l0oP8ePgHORaajyj7ONjoeudv_zQ9XN7xU447S3QznzOoasuWAFoN4682Fhf99Kjl6rhDCzmZhTwQw9drP7s41nNA5SwgEhoZj-X9KkNW5GbWjA95eb8uVRRWk8dOnVje6j8mlJuOtKdhMxQ8N5n0vBYYhiss9c4XervBjWAxwAMdbRaQN0iPZtMzIkxKLYxBZDvTnYSAqzpvfGPzkSI-Ze_hUZs2hp-ADNnYUJBf_LzFmKyqHjPSFQ7A"
+      }
+    }`
+
+	var assertion Assertion
+	err := json.Unmarshal([]byte(assertionVal), &assertion)
+	require.NoError(t, err, "Error deserializing the assertion with a JSON object in the statement value")
+
+	var expectedAssertionValue, _ = jcs.Transform([]byte(`{
+          "ocl": {
+            "pol": "2ccf11cb-6c9a-4e49-9746-a7f0a295945d",
+            "cls": "SECRET",
+            "catl": [
+              {
+                "type": "P",
+                "name": "Releasable To",
+                "vals": [
+                  "usa"
+                ]
+              }
+            ],
+            "dcr": "2024-12-17T13:00:52Z"
+          },
+          "context": {
+            "@base": "urn:nato:stanag:5636:A:1:elements:json"
+          }
+        }`))
+	actualAssertionValue, err := jcs.Transform([]byte(assertion.Statement.Value))
+	require.NoError(t, err, "Error transforming the assertion statement value")
+	assert.Equal(t, expectedAssertionValue, actualAssertionValue)
+}
+
+func TestDeserializingAssertionWithStringInStatementValue(t *testing.T) {
+	// the assertion has a JSON object in the statement value
+	assertionVal := ` {
+      "id": "bacbe31eab384df39d35a5fbe83778de",
+      "type": "handling",
+      "scope": "tdo",
+      "appliesToState": null,
+      "statement": {
+        "format": "json-structured",
+        "value": "this is a value"
+      },
+      "binding": {
+        "method": "jws",
+        "signature": "eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9.eyJDb25maWRlbnRpYWxpdHlJbmZvcm1hdGlvbiI6InsgXCJvY2xcIjogeyBcInBvbFwiOiBcIjJjY2YxMWNiLTZjOWEtNGU0OS05NzQ2LWE3ZjBhMjk1OTQ1ZFwiLCBcImNsc1wiOiBcIlNFQ1JFVFwiLCBcImNhdGxcIjogWyB7IFwidHlwZVwiOiBcIlBcIiwgXCJuYW1lXCI6IFwiUmVsZWFzYWJsZSBUb1wiLCBcInZhbHNcIjogWyBcInVzYVwiIF0gfSBdLCBcImRjclwiOiBcIjIwMjQtMTItMTdUMTM6MDA6NTJaXCIgfSwgXCJjb250ZXh0XCI6IHsgXCJAYmFzZVwiOiBcInVybjpuYXRvOnN0YW5hZzo1NjM2OkE6MTplbGVtZW50czpqc29uXCIgfSB9In0.LlOzRLKKXMAqXDNsx9Ha5915CGcAkNLuBfI7jJmx6CnfQrLXhlRHWW3_aLv5DPsKQC6vh9gDQBH19o7q7EcukvK4IabA4l0oP8ePgHORaajyj7ONjoeudv_zQ9XN7xU447S3QznzOoasuWAFoN4682Fhf99Kjl6rhDCzmZhTwQw9drP7s41nNA5SwgEhoZj-X9KkNW5GbWjA95eb8uVRRWk8dOnVje6j8mlJuOtKdhMxQ8N5n0vBYYhiss9c4XervBjWAxwAMdbRaQN0iPZtMzIkxKLYxBZDvTnYSAqzpvfGPzkSI-Ze_hUZs2hp-ADNnYUJBf_LzFmKyqHjPSFQ7A"
+      }
+    }`
+
+	var assertion Assertion
+	err := json.Unmarshal([]byte(assertionVal), &assertion)
+	require.NoError(t, err, "Error deserializing the assertion with a JSON object in the statement value")
+
+	assert.Equal(t, "this is a value", assertion.Statement.Value)
+}