Limit nesting depth

misc_tests/jsoniter_nested_test.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"github.com/json-iterator/go"
 	"reflect"
+	"strings"
 	"testing"
 )
 
@@ -15,6 +16,243 @@ type Level2 struct {
 	World string
 }
 
+func Test_deep_nested(t *testing.T) {
+	type unstructured interface{}
+
+	testcases := []struct {
+		name        string
+		data        []byte
+		expectError string
+	}{
+		{
+			name:        "array under maxDepth",
+			data:        []byte(`{"a":` + strings.Repeat(`[`, 10000-1) + strings.Repeat(`]`, 10000-1) + `}`),
+			expectError: "",
+		},
+		{
+			name:        "array over maxDepth",
+			data:        []byte(`{"a":` + strings.Repeat(`[`, 10000) + strings.Repeat(`]`, 10000) + `}`),
+			expectError: "max depth",
+		},
+		{
+			name:        "object under maxDepth",
+			data:        []byte(`{"a":` + strings.Repeat(`{"a":`, 10000-1) + `0` + strings.Repeat(`}`, 10000-1) + `}`),
+			expectError: "",
+		},
+		{
+			name:        "object over maxDepth",
+			data:        []byte(`{"a":` + strings.Repeat(`{"a":`, 10000) + `0` + strings.Repeat(`}`, 10000) + `}`),
+			expectError: "max depth",
+		},
+	}
+
+	targets := []struct {
+		name string
+		new  func() interface{}
+	}{
+		{
+			name: "unstructured",
+			new: func() interface{} {
+				var v interface{}
+				return &v
+			},
+		},
+		{
+			name: "typed named field",
+			new: func() interface{} {
+				v := struct {
+					A interface{} `json:"a"`
+				}{}
+				return &v
+			},
+		},
+		{
+			name: "typed missing field",
+			new: func() interface{} {
+				v := struct {
+					B interface{} `json:"b"`
+				}{}
+				return &v
+			},
+		},
+		{
+			name: "typed 1 field",
+			new: func() interface{} {
+				v := struct {
+					A interface{} `json:"a"`
+				}{}
+				return &v
+			},
+		},
+		{
+			name: "typed 2 field",
+			new: func() interface{} {
+				v := struct {
+					A interface{} `json:"a"`
+					B interface{} `json:"b"`
+				}{}
+				return &v
+			},
+		},
+		{
+			name: "typed 3 field",
+			new: func() interface{} {
+				v := struct {
+					A interface{} `json:"a"`
+					B interface{} `json:"b"`
+					C interface{} `json:"c"`
+				}{}
+				return &v
+			},
+		},
+		{
+			name: "typed 4 field",
+			new: func() interface{} {
+				v := struct {
+					A interface{} `json:"a"`
+					B interface{} `json:"b"`
+					C interface{} `json:"c"`
+					D interface{} `json:"d"`
+				}{}
+				return &v
+			},
+		},
+		{
+			name: "typed 5 field",
+			new: func() interface{} {
+				v := struct {
+					A interface{} `json:"a"`
+					B interface{} `json:"b"`
+					C interface{} `json:"c"`
+					D interface{} `json:"d"`
+					E interface{} `json:"e"`
+				}{}
+				return &v
+			},
+		},
+		{
+			name: "typed 6 field",
+			new: func() interface{} {
+				v := struct {
+					A interface{} `json:"a"`
+					B interface{} `json:"b"`
+					C interface{} `json:"c"`
+					D interface{} `json:"d"`
+					E interface{} `json:"e"`
+					F interface{} `json:"f"`
+				}{}
+				return &v
+			},
+		},
+		{
+			name: "typed 7 field",
+			new: func() interface{} {
+				v := struct {
+					A interface{} `json:"a"`
+					B interface{} `json:"b"`
+					C interface{} `json:"c"`
+					D interface{} `json:"d"`
+					E interface{} `json:"e"`
+					F interface{} `json:"f"`
+					G interface{} `json:"g"`
+				}{}
+				return &v
+			},
+		},
+		{
+			name: "typed 8 field",
+			new: func() interface{} {
+				v := struct {
+					A interface{} `json:"a"`
+					B interface{} `json:"b"`
+					C interface{} `json:"c"`
+					D interface{} `json:"d"`
+					E interface{} `json:"e"`
+					F interface{} `json:"f"`
+					G interface{} `json:"g"`
+					H interface{} `json:"h"`
+				}{}
+				return &v
+			},
+		},
+		{
+			name: "typed 9 field",
+			new: func() interface{} {
+				v := struct {
+					A interface{} `json:"a"`
+					B interface{} `json:"b"`
+					C interface{} `json:"c"`
+					D interface{} `json:"d"`
+					E interface{} `json:"e"`
+					F interface{} `json:"f"`
+					G interface{} `json:"g"`
+					H interface{} `json:"h"`
+					I interface{} `json:"i"`
+				}{}
+				return &v
+			},
+		},
+		{
+			name: "typed 10 field",
+			new: func() interface{} {
+				v := struct {
+					A interface{} `json:"a"`
+					B interface{} `json:"b"`
+					C interface{} `json:"c"`
+					D interface{} `json:"d"`
+					E interface{} `json:"e"`
+					F interface{} `json:"f"`
+					G interface{} `json:"g"`
+					H interface{} `json:"h"`
+					I interface{} `json:"i"`
+					J interface{} `json:"j"`
+				}{}
+				return &v
+			},
+		},
+		{
+			name: "typed 11 field",
+			new: func() interface{} {
+				v := struct {
+					A interface{} `json:"a"`
+					B interface{} `json:"b"`
+					C interface{} `json:"c"`
+					D interface{} `json:"d"`
+					E interface{} `json:"e"`
+					F interface{} `json:"f"`
+					G interface{} `json:"g"`
+					H interface{} `json:"h"`
+					I interface{} `json:"i"`
+					J interface{} `json:"j"`
+					K interface{} `json:"k"`
+				}{}
+				return &v
+			},
+		},
+	}
+
+	for _, tc := range testcases {
+		t.Run(tc.name, func(t *testing.T) {
+			for _, target := range targets {
+				t.Run(target.name, func(t *testing.T) {
+					err := jsoniter.Unmarshal(tc.data, target.new())
+					if len(tc.expectError) == 0 {
+						if err != nil {
+							t.Errorf("unexpected error: %v", err)
+						}
+					} else {
+						if err == nil {
+							t.Errorf("expected error, got none")
+						} else if !strings.Contains(err.Error(), tc.expectError) {
+							t.Errorf("expected error containing '%s', got: %v", tc.expectError, err)
+						}
+					}
+				})
+			}
+		})
+	}
+}
+
 func Test_nested(t *testing.T) {
 	iter := jsoniter.ParseString(jsoniter.ConfigDefault, `{"hello": [{"world": "value1"}, {"world": "value2"}]}`)
 	l1 := Level1{}