refactor(windows): clean up Chrome ABE module (#574)

* refactor(abe): remove --abe-key flag and its global state
* refactor(abe): rework scratch protocol and Go/C structure

Author: moonD4rk

.golangci.yml

@@ -122,6 +122,7 @@ linters:
         - G117 # struct field matches secret pattern — false positive on Password fields
         - G204 # exec.Command with variable — required for macOS `security` command
         - G304 # file inclusion via variable — required for dynamic browser paths
+        - G703 # path traversal via taint analysis — same false-positive class as G304 (gosec 2.22+ / golangci-lint 2.11+)
         - G401 # weak crypto SHA1 — required for Chromium PBKDF2 key derivation
         - G402 # TLS MinVersion — not applicable (no TLS in this tool)
         - G405 # weak crypto DES — required for Firefox 3DES decryption

CLAUDE.md

@@ -42,9 +42,24 @@ go mod tidy
 go mod verify
 ```
 
+## Chrome ABE Payload (Windows only)
+
+Chrome 127+ cookies (v20) decrypt via a C payload reflectively injected into `chrome.exe`. Sources in `crypto/windows/abe_native/`; design in [RFC-010](rfcs/010-chrome-abe-integration.md).
+
+```bash
+make payload         # build the DLL (needs zig: brew install zig)
+make build-windows   # cross-compile hack-browser-data.exe with payload embedded
+make gen-layout      # regenerate Go layout constants from bootstrap_layout.h
+make payload-clean   # rm crypto/*.bin
+```
+
+- Default `go build` links a stub that errors at runtime when ABE is needed — contributors not touching Windows ABE need no zig.
+- `-tags abe_embed` embeds the payload via `//go:embed` (see `crypto/abe_embed_windows.go` / `crypto/abe_stub_windows.go`).
+
 ## Code Conventions
 
 - **Platform code**: use build tags (`_darwin.go`, `_windows.go`, `_linux.go`)
+- **C payload**: all sources in `crypto/windows/abe_native/` are first-party (no vendored C). See RFC-010 §9.2 for why Stephen Fewer's reflective loader was rejected.
 - **Error handling**: `fmt.Errorf("context: %w", err)` for wrapping, never `_ =` to ignore errors
 - **Logging**: `log.Debugf` for record-level diagnostics, `log.Infof` for user-facing progress/status, `log.Warnf` for unexpected conditions. Extract methods should return errors, not log them.
 - **Naming**: follow Go conventions — `Config` not `BrowserConfig`, `Extract` not `BrowsingData`

browser/chromium/decrypt.go

@@ -20,7 +20,9 @@ func decryptValue(masterKey, ciphertext []byte) ([]byte, error) {
 		// v11 is Linux-only and shares v10's AES-CBC path; only the key source differs.
 		return crypto.DecryptChromium(masterKey, ciphertext)
 	case crypto.CipherV20:
-		return crypto.DecryptChromium(masterKey, ciphertext)
+		// v20 is cross-platform AES-GCM; routed through a dedicated function so
+		// Linux/macOS CI can exercise the same decryption path as Windows.
+		return crypto.DecryptChromiumV20(masterKey, ciphertext)
 	case crypto.CipherDPAPI:
 		return crypto.DecryptDPAPI(ciphertext)
 	default:

browser/chromium/decrypt_v20_test.go

@@ -0,0 +1,35 @@
+package chromium
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/moond4rk/hackbrowserdata/crypto"
+)
+
+// TestDecryptValue_V20 is cross-platform because v20's ciphertext format
+// (AES-GCM with 12-byte nonce) is platform-independent; only the key source
+// (Chrome ABE on Windows) differs by OS. Running on Linux/macOS CI protects
+// the routing in decryptValue + crypto.DecryptChromiumV20 from regressions.
+func TestDecryptValue_V20(t *testing.T) {
+	plaintext := []byte("v20_test_value")
+	nonce := []byte("v20_nonce_12") // 12-byte AES-GCM nonce
+
+	gcm, err := crypto.AESGCMEncrypt(testAESKey, nonce, plaintext)
+	require.NoError(t, err)
+
+	// v20 layout: "v20" (3B) + nonce (12B) + ciphertext+tag
+	ciphertext := append([]byte("v20"), append(nonce, gcm...)...)
+
+	got, err := decryptValue(testAESKey, ciphertext)
+	require.NoError(t, err)
+	assert.Equal(t, plaintext, got)
+}
+
+func TestDecryptValue_V20_ShortCiphertext(t *testing.T) {
+	// Missing nonce (prefix only) must error, not panic.
+	_, err := decryptValue(testAESKey, []byte("v20"))
+	require.Error(t, err)
+}

cmd/hack-browser-data/dump.go

@@ -8,7 +8,6 @@ import (
 	"github.com/spf13/cobra"
 
 	"github.com/moond4rk/hackbrowserdata/browser"
-	"github.com/moond4rk/hackbrowserdata/crypto"
 	"github.com/moond4rk/hackbrowserdata/log"
 	"github.com/moond4rk/hackbrowserdata/output"
 	"github.com/moond4rk/hackbrowserdata/types"
@@ -23,7 +22,6 @@ func dumpCmd() *cobra.Command {
 		outputDir    string
 		profilePath  string
 		keychainPw   string
-		abeKey       string
 		compress     bool
 	)
 
@@ -36,12 +34,6 @@ func dumpCmd() *cobra.Command {
   hack-browser-data dump -f cookie-editor
   hack-browser-data dump --zip`,
 		RunE: func(cmd *cobra.Command, args []string) error {
-			if abeKey != "" {
-				if err := crypto.SetABEMasterKeyFromHex(abeKey); err != nil {
-					return fmt.Errorf("--abe-key: %w", err)
-				}
-			}
-
 			browsers, err := browser.PickBrowsers(browser.PickOptions{
 				Name:             browserName,
 				ProfilePath:      profilePath,
@@ -94,9 +86,6 @@ func dumpCmd() *cobra.Command {
 	cmd.Flags().StringVarP(&outputDir, "dir", "d", "results", "output directory")
 	cmd.Flags().StringVarP(&profilePath, "profile-path", "p", "", "custom profile dir path, get with chrome://version")
 	cmd.Flags().StringVar(&keychainPw, "keychain-pw", "", "macOS keychain password")
-	cmd.Flags().StringVarP(&abeKey, "abe-key", "k", "",
-		"Windows only: pre-decrypted Chrome ABE master key (64 hex chars / 32 bytes). "+
-			"When set, skips the in-process elevation_service injection.")
 	cmd.Flags().BoolVar(&compress, "zip", false, "compress output to zip")
 
 	return cmd

crypto/abe_embed_windows.go

@@ -12,7 +12,7 @@ import (
 //go:embed abe_extractor_amd64.bin
 var abePayloadAmd64 []byte
 
-func getPayloadForArch(arch string) ([]byte, error) {
+func ABEPayload(arch string) ([]byte, error) {
 	switch arch {
 	case "amd64":
 		if len(abePayloadAmd64) == 0 {

crypto/abe_stub_other.go

@@ -4,7 +4,7 @@ package crypto
 
 import "fmt"
 
-func getPayloadForArch(arch string) ([]byte, error) {
+func ABEPayload(arch string) ([]byte, error) {
 	return nil, fmt.Errorf(
 		"abe: payload not embedded in this build (rebuild with -tags abe_embed; arch=%s)",
 		arch,

crypto/abe_stub_windows.go

@@ -45,6 +45,27 @@ func DES3Decrypt(key, iv, ciphertext []byte) ([]byte, error) {
 	return cbcDecrypt(block, iv, ciphertext)
 }
 
+// gcmNonceSize is the AES-GCM standard nonce size used by Chromium's v10/v20
+// cipher formats. Cross-platform because the v20 ciphertext layout is the
+// same regardless of host OS (only Windows currently produces v20).
+const gcmNonceSize = 12
+
+// DecryptChromiumV20 decrypts a Chromium v20 (App-Bound Encryption) ciphertext.
+// Format: "v20" prefix (3B) + nonce (12B) + AES-GCM(payload + 16B tag).
+//
+// Cross-platform: v20 is only produced by Chrome on Windows today, but the
+// decryption math is platform-neutral. Keeping it here rather than in
+// crypto_windows.go ensures the routing in browser/chromium/decrypt.go stays
+// testable on Linux/macOS CI.
+func DecryptChromiumV20(key, ciphertext []byte) ([]byte, error) {
+	if len(ciphertext) < versionPrefixLen+gcmNonceSize {
+		return nil, errShortCiphertext
+	}
+	nonce := ciphertext[versionPrefixLen : versionPrefixLen+gcmNonceSize]
+	payload := ciphertext[versionPrefixLen+gcmNonceSize:]
+	return AESGCMDecrypt(key, nonce, payload)
+}
+
 // AESGCMEncrypt encrypts data using AES-GCM mode.
 func AESGCMEncrypt(key, nonce, plaintext []byte) ([]byte, error) {
 	block, err := aes.NewCipher(key)