Extract all files from encrypted stream with inspect (#20937)

Allow multiple private keys and extract all files from streams.

Place files in the folder with `.enc` removed.

Do basic checks so streams cannot traverse outside of the folder.
This commit is contained in:
Klaus Post 2025-02-17 09:09:42 -08:00 committed by GitHub
parent 727a803bc0
commit b312f13473
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
2 changed files with 70 additions and 50 deletions

View File

@ -22,6 +22,9 @@ import (
"fmt"
"io"
"os"
"path/filepath"
"strings"
"unicode/utf8"
"github.com/minio/madmin-go/v3/estream"
)
@ -30,18 +33,18 @@ type keepFileErr struct {
error
}
func extractInspectV2(pk []byte, r io.Reader, w io.Writer, okMsg string) error {
privKey, err := bytesToPrivateKey(pk)
if err != nil {
return fmt.Errorf("decoding key returned: %w", err)
}
func extractInspectV2(pks [][]byte, r io.Reader, extractDir string) error {
sr, err := estream.NewReader(r)
if err != nil {
return err
}
for _, pk := range pks {
privKey, err := bytesToPrivateKey(pk)
if err != nil {
return fmt.Errorf("decoding key returned: %w", err)
}
sr.SetPrivateKey(privKey)
}
sr.ReturnNonDecryptable(true)
// Debug corrupted streams.
@ -60,33 +63,29 @@ func extractInspectV2(pk []byte, r io.Reader, w io.Writer, okMsg string) error {
return errors.New("no data found on stream")
}
if errors.Is(err, estream.ErrNoKey) {
if stream.Name == "inspect.zip" {
return errors.New("incorrect private key")
}
fmt.Println("Skipping", stream.Name, "no private key")
if err := stream.Skip(); err != nil {
return fmt.Errorf("stream skip: %w", err)
}
continue
}
if extracted {
return keepFileErr{fmt.Errorf("next stream: %w", err)}
}
return fmt.Errorf("next stream: %w", err)
}
if stream.Name == "inspect.zip" {
if extracted {
return keepFileErr{errors.New("multiple inspect.zip streams found")}
if strings.Contains(stream.Name, "..") || !utf8.ValidString(stream.Name) {
return fmt.Errorf("invalid stream name: %q", stream.Name)
}
_, err := io.Copy(w, stream)
dst := filepath.Join(extractDir, stream.Name)
os.Mkdir(extractDir, 0o755)
w, err := os.Create(dst)
if err != nil {
return fmt.Errorf("creating output file: %w", err)
}
_, err = io.Copy(w, stream)
if err != nil {
return fmt.Errorf("reading inspect stream: %w", err)
}
fmt.Println(okMsg)
fmt.Printf("Extracted: %s\n", dst)
extracted = true
continue
}
if err := stream.Skip(); err != nil {
return fmt.Errorf("stream skip: %w", err)
}
}
}

View File

@ -51,15 +51,34 @@ func main() {
generateKeys()
os.Exit(0)
}
var privateKey []byte
var privateKeys [][]byte
if *keyHex == "" {
if b, err := os.ReadFile(*privKeyPath); err == nil {
privateKey = b
fmt.Println("Using private key from", *privKeyPath)
// Attempt to load private key(s)
n := 1
var base, ext string
base = *privKeyPath
if idx := strings.LastIndexByte(base, '.'); idx != -1 {
ext = base[idx:]
base = base[:idx]
}
for {
// Automatically read "file.ext", "file-2.ext", "file-3.ext"...
fn := base + ext
if n > 1 {
fn = fmt.Sprintf("%s-%d%s", base, n, ext)
}
if b, err := os.ReadFile(fn); err == nil {
privateKeys = append(privateKeys, b)
fmt.Println("Added private key from", fn)
} else {
break
}
n++
}
// Prompt for decryption key if no --key or --private-key are provided
if len(privateKey) == 0 && !*stdin {
if len(privateKeys) == 0 && !*stdin {
reader := bufio.NewReader(os.Stdin)
fmt.Print("Enter Decryption Key: ")
@ -91,17 +110,20 @@ func main() {
var err error
inputs, err = filepathx.Glob(flag.Args()[0])
fatalErr(err)
if len(inputs) == 0 {
fmt.Println("Usage: No input found")
}
default:
flag.Usage()
fatalIf(true, "Only 1 file can be decrypted")
os.Exit(1)
}
for _, input := range inputs {
processFile(input, privateKey)
processFile(input, privateKeys)
}
}
func processFile(inputFileName string, privateKey []byte) {
func processFile(inputFileName string, privateKeys [][]byte) {
// Calculate the output file name
var outputFileName string
switch {
@ -115,6 +137,14 @@ func processFile(inputFileName string, privateKey []byte) {
outputFileName = inputFileName + ".decrypted"
}
// Open the input and create the output file
input, err := os.Open(inputFileName)
fatalErr(err)
defer input.Close()
// Decrypt the inspect data
switch {
case *keyHex != "":
// Backup any already existing output file
_, err := os.Stat(outputFileName)
if err == nil {
@ -123,24 +153,15 @@ func processFile(inputFileName string, privateKey []byte) {
fatalErr(err)
}
}
// Open the input and create the output file
input, err := os.Open(inputFileName)
fatalErr(err)
defer input.Close()
output, err := os.Create(outputFileName)
fatalErr(err)
// Decrypt the inspect data
msg := fmt.Sprintf("output written to %s", outputFileName)
switch {
case *keyHex != "":
err = extractInspectV1(*keyHex, input, output, msg)
case len(privateKey) != 0:
err = extractInspectV2(privateKey, input, output, msg)
}
output.Close()
case len(privateKeys) != 0:
outputFileName := strings.TrimSuffix(outputFileName, ".zip")
err = extractInspectV2(privateKeys, input, outputFileName)
}
if err != nil {
var keep keepFileErr