feat: parse encrypted isphere packet logs

2026-07-09 22:53:23 +08:00
parent de3bb922da
commit 4d5b314f83
5 changed files with 420 additions and 23 deletions
--- a/internal/isphere/logcodec/codec_test.go
+++ b/internal/isphere/logcodec/codec_test.go
@@ -0,0 +1,43 @@
+package logcodec
+
+import (
+	"crypto/cipher"
+	"crypto/des"
+	"encoding/base64"
+	"testing"
+)
+
+func TestDecryptLineWithKnownPolicyRoundTrip(t *testing.T) {
+	plaintext := "--------------------------------------------------------------------------------------------------------------------------------------------\r\n2026/7/7 15:30:07\r\n<message id=\"msg-1\" from=\"sender@imopenfire1-lanzhou/imp_pc_4.1.2.6842\" to=\"receiver@imopenfire1-lanzhou\" type=\"chat\"><body>redacted</body></message>"
+	ciphertext := encryptLineForTest(t, plaintext)
+
+	got, err := DecryptLine(ciphertext)
+	if err != nil {
+		t.Fatalf("DecryptLine returned error: %v", err)
+	}
+	if got != plaintext {
+		t.Fatalf("DecryptLine() = %q, want %q", got, plaintext)
+	}
+}
+
+func encryptLineForTest(t *testing.T, plaintext string) string {
+	t.Helper()
+	block, err := des.NewCipher([]byte("hyhccdtm"))
+	if err != nil {
+		t.Fatalf("NewCipher: %v", err)
+	}
+	plain := padPKCS7ForTest([]byte(plaintext), des.BlockSize)
+	ciphertext := make([]byte, len(plain))
+	iv := []byte{0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF}
+	cipher.NewCBCEncrypter(block, iv).CryptBlocks(ciphertext, plain)
+	return base64.StdEncoding.EncodeToString(ciphertext)
+}
+
+func padPKCS7ForTest(data []byte, blockSize int) []byte {
+	pad := blockSize - len(data)%blockSize
+	out := append([]byte(nil), data...)
+	for i := 0; i < pad; i++ {
+		out = append(out, byte(pad))
+	}
+	return out
+}