Merge pull request #1645 from projectdiscovery/gzip-decode

Added gzip_decode helper function

v2/pkg/operators/common/dsl/dsl.go

@@ -11,6 +11,7 @@ import (
 	"errors"
 	"fmt"
 	"html"
+	"io"
 	"math"
 	"math/rand"
 	"net/url"
@@ -101,12 +102,26 @@ func init() {
 			buffer := &bytes.Buffer{}
 			writer := gzip.NewWriter(buffer)
 			if _, err := writer.Write([]byte(args[0].(string))); err != nil {
+				_ = writer.Close()
 				return "", err
 			}
 			_ = writer.Close()
 
 			return buffer.String(), nil
 		}),
+		"gzip_decode": makeDslFunction(1, func(args ...interface{}) (interface{}, error) {
+			reader, err := gzip.NewReader(strings.NewReader(args[0].(string)))
+			if err != nil {
+				return "", err
+			}
+			data, err := io.ReadAll(reader)
+			if err != nil {
+				_ = reader.Close()
+				return "", err
+			}
+			_ = reader.Close()
+			return string(data), nil
+		}),
 		"base64_py": makeDslFunction(1, func(args ...interface{}) (interface{}, error) {
 			// python encodes to base64 with lines of 76 bytes terminated by new line "\n"
 			stdBase64 := base64.StdEncoding.EncodeToString([]byte(types.ToString(args[0])))

v2/pkg/operators/common/dsl/dsl_test.go

@@ -1,12 +1,9 @@
 package dsl
 
 import (
-	"compress/gzip"
 	"fmt"
-	"io/ioutil"
 	"math"
 	"regexp"
-	"strings"
 	"testing"
 	"time"
 
@@ -40,15 +37,18 @@ func TestDSLTimeComparison(t *testing.T) {
 
 func TestDSLGzipSerialize(t *testing.T) {
 	compiled, err := govaluate.NewEvaluableExpressionWithFunctions("gzip(\"hello world\")", HelperFunctions())
-	require.Nil(t, err, "could not compare time")
+	require.Nil(t, err, "could not compile encoder")
 
 	result, err := compiled.Evaluate(make(map[string]interface{}))
 	require.Nil(t, err, "could not evaluate compare time")
 
-	reader, _ := gzip.NewReader(strings.NewReader(types.ToString(result)))
+	compiled, err = govaluate.NewEvaluableExpressionWithFunctions("gzip_decode(data)", HelperFunctions())
-	data, _ := ioutil.ReadAll(reader)
+	require.Nil(t, err, "could not compile decoder")
 
-	require.Equal(t, "hello world", string(data), "could not get gzip encoded data")
+	data, err := compiled.Evaluate(map[string]interface{}{"data": result})
+	require.Nil(t, err, "could not evaluate decoded data")
+
+	require.Equal(t, "hello world", data.(string), "could not get gzip encoded data")
 }
 
 func TestDslFunctionSignatures(t *testing.T) {
@@ -102,6 +102,7 @@ func TestGetPrintableDslFunctionSignatures(t *testing.T) {
 	contains(arg1, arg2 interface{}) interface{}
 	generate_java_gadget(arg1, arg2, arg3 interface{}) interface{}
 	gzip(arg1 interface{}) interface{}
+	gzip_decode(arg1 interface{}) interface{}
 	hex_decode(arg1 interface{}) interface{}
 	hex_encode(arg1 interface{}) interface{}
 	html_escape(arg1 interface{}) interface{}