Files
Xray-core/common/lua/privileged.go
T

81 lines
2.4 KiB
Go

package lua
import (
"bytes"
"crypto/ed25519"
"crypto/sha256"
"encoding/base64"
"sync"
"github.com/xtls/xray-core/common/errors"
)
var privilegedKey struct {
sync.Once
publicKey ed25519.PublicKey
}
// SetPrivilegedPublicKey configures the trusted Ed25519 public key once at
// startup, before compiling scripts. An empty value disables authorization.
// Nonempty values must be unpadded Base64URL encodings of exactly 32 bytes.
func SetPrivilegedPublicKey(value string) error {
var publicKey ed25519.PublicKey
if value != "" {
decoded, err := decodePrivilegedValue(value, ed25519.PublicKeySize)
if err != nil {
return errors.New("invalid Lua privileged public key").Base(err)
}
publicKey = ed25519.PublicKey(decoded)
}
privilegedKey.Do(func() {
privilegedKey.publicKey = publicKey
})
return nil
}
func decodePrivilegedValue(value string, size int) ([]byte, error) {
encoding := base64.RawURLEncoding.Strict()
if len(value) != encoding.EncodedLen(size) {
return nil, errors.New("expected an unpadded Base64URL encoding of ", size, " bytes")
}
decoded, err := encoding.DecodeString(value)
if err != nil || len(decoded) != size || encoding.EncodeToString(decoded) != value {
return nil, errors.New("expected an unpadded Base64URL encoding of ", size, " bytes")
}
return decoded, nil
}
func verifyPrivilegedSignature(code []byte) (bool, error) {
for len(code) != 0 {
line, rest, _ := bytes.Cut(code, []byte{'\n'})
code = rest
line = bytes.TrimSuffix(line, []byte{'\r'})
if len(bytes.TrimSpace(line)) == 0 {
continue
}
line, found := bytes.CutPrefix(bytes.TrimLeft(line, " \t"), []byte("--"))
if !found {
return false, nil
}
value, found := bytes.CutPrefix(bytes.TrimLeft(line, " \t"), []byte("@xray:privileged-signature="))
if !found {
return false, nil
}
publicKey := privilegedKey.publicKey
if len(publicKey) == 0 {
return false, errors.New("Lua privileged signature requires --lua-privileged-pubkey")
}
signature, err := decodePrivilegedValue(string(bytes.TrimSpace(value)), ed25519.SignatureSize)
if err != nil {
return false, errors.New("invalid Lua privileged signature").Base(err)
}
digest := sha256.Sum256(bytes.TrimSpace(rest))
if !ed25519.Verify(publicKey, digest[:], signature) {
return false, errors.New("Lua privileged signature verification failed")
}
return true, nil
}
return false, nil
}