perbaikan decript

internal/services/bpjs/response.go

@@ -2,49 +2,110 @@ package services
 
 import (
 	helper "api-service/internal/helpers/bpjs"
+	"bytes"
+	"compress/gzip"
 	"crypto/aes"
 	"crypto/cipher"
 	"crypto/sha256"
 	"encoding/base64"
 	"errors"
-
-	lzstring "github.com/daku10/go-lz-string"
+	"io"
+	"log"
 )
 
+func min(a, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}
+
 // ResponseVclaim decrypts the encrypted response from VClaim API
 func ResponseVclaim(encrypted string, key string) (string, error) {
+	log.Println("ResponseVclaim: Starting decryption process")
+	log.Printf("ResponseVclaim: Encrypted string: %s", encrypted)
+
+	// Pad the base64 string if needed
+	if len(encrypted)%4 != 0 {
+		padding := (4 - len(encrypted)%4) % 4
+		for i := 0; i < padding; i++ {
+			encrypted += "="
+		}
+		log.Printf("ResponseVclaim: Padded encrypted string: %s", encrypted)
+	}
+
 	cipherText, err := base64.StdEncoding.DecodeString(encrypted)
 	if err != nil {
+		log.Printf("ResponseVclaim: Failed to decode base64: %v", err)
 		return "", err
 	}
+	log.Printf("ResponseVclaim: Base64 decoded successfully, length: %d", len(cipherText))
 
 	hash := sha256.Sum256([]byte(key))
 
 	block, err := aes.NewCipher(hash[:])
 	if err != nil {
+		log.Printf("ResponseVclaim: Failed to create AES cipher: %v", err)
 		return "", err
 	}
 
 	if len(cipherText) < aes.BlockSize {
+		log.Println("ResponseVclaim: CipherText too short")
 		return "", errors.New("cipherText too short")
 	}
 
 	iv := hash[:aes.BlockSize]
 
 	if len(cipherText)%aes.BlockSize != 0 {
+		log.Println("ResponseVclaim: CipherText not multiple of block size")
 		return "", errors.New("cipherText is not a multiple of the block size")
 	}
 
 	mode := cipher.NewCBCDecrypter(block, iv)
 	mode.CryptBlocks(cipherText, cipherText)
+	log.Println("ResponseVclaim: AES decryption completed")
 
 	// cipherText, _ = pkcs7.Unpad(cipherText, aes.BlockSize)
 	cipherText = helper.RemovePKCS7Padding(cipherText)
-	data, err := lzstring.DecompressFromEncodedURIComponent(string(cipherText))
-	// data, err := helper.DecompressFromEncodedUriComponent(string(cipherText))
+	log.Printf("ResponseVclaim: PKCS7 padding removed, length: %d", len(cipherText))
+
+	var data string
+
+	// Try gzip decompression first
+	reader, err := gzip.NewReader(bytes.NewReader(cipherText))
 	if err != nil {
-		return "", err
+		log.Printf("ResponseVclaim: Gzip decompression failed: %v, trying LZ-string decompression", err)
+		// Try lz-string decompression using helper function
+		data, err := helper.StringDecrypt(key, string(cipherText))
+		if err != nil || len(data) == 0 {
+			log.Printf("ResponseVclaim: Helper StringDecrypt failed or empty: %v, trying without decompression", err)
+			// Try without decompression
+			data = string(cipherText)
+			log.Printf("ResponseVclaim: Using decrypted data without decompression, data length: %d", len(data))
+		} else {
+			log.Printf("ResponseVclaim: Helper StringDecrypt successful, data length: %d, data: %s", len(data), data[:min(100, len(data))])
+		}
+	} else {
+		defer reader.Close()
+		decompressed, err := io.ReadAll(reader)
+		if err != nil {
+			log.Printf("ResponseVclaim: Failed to read gzip decompressed data: %v, trying LZ-string decompression", err)
+			// Try lz-string decompression using helper function
+			data, err := helper.StringDecrypt(key, string(cipherText))
+			if err != nil || len(data) == 0 {
+				log.Printf("ResponseVclaim: Helper StringDecrypt failed or empty: %v, using data without decompression", err)
+				data = string(cipherText)
+				log.Printf("ResponseVclaim: Using decrypted data without decompression, data length: %d", len(data))
+			} else {
+				log.Printf("ResponseVclaim: Helper StringDecrypt successful, data length: %d", len(data))
+			}
+		} else {
+			data = string(decompressed)
+			log.Printf("ResponseVclaim: Gzip decompression successful, data length: %d", len(data))
+		}
 	}
 
+	log.Printf("ResponseVclaim: Final data length: %d, data: %s", len(data), data[:min(100, len(data))])
+	log.Println("ResponseVclaim: Decryption process completed successfully")
 	return data, nil
 }