milvus/pkg/streaming/util/message/cipher.go

110 lines
2.9 KiB
Go

package message
import (
"strings"
"sync"
"time"
"github.com/cockroachdb/errors"
"go.uber.org/zap"
"github.com/milvus-io/milvus-proto/go-api/v2/hook"
"github.com/milvus-io/milvus/pkg/v2/log"
)
// cipher is a global variable that is used to encrypt and decrypt messages.
// It should be initialized at initialization stage.
var (
cipher hook.Cipher
initOnce sync.Once
)
// RegisterCipher registers a cipher to be used for encrypting and decrypting messages.
// It should be called only once when the program starts and initialization stage.
func RegisterCipher(c hook.Cipher) {
initOnce.Do(func() {
cipher = c
})
}
// mustGetCipher returns the registered cipher.
func mustGetCipher() hook.Cipher {
if cipher == nil {
panic("cipher not registered")
}
return cipher
}
// ErrKmsKeyInvalid is the error returned when a KMS key is invalid or revoked.
// This error is also defined in the milvus-cloud-plugin. It is checked using `errors.Is`
// to allow for proper error wrapping and reliable error handling.
var ErrKmsKeyInvalid = errors.New("kms key invalid")
func isKmsKeyInvalidError(err error) bool {
if err == nil {
return false
}
// Check both errors.Is for local errors and string matching for errors
// that cross the plugin boundary (which lose type information)
return errors.Is(err, ErrKmsKeyInvalid) || strings.Contains(err.Error(), "kms key invalid")
}
// getDecryptorWithRetry wraps cipher.GetDecryptor with retry logic for streaming node consumption.
// It retries with exponential backoff if the error is KmsKeyInvalid (retriable).
// For other errors, it returns immediately without retry.
func getDecryptorWithRetry(ezID, collectionID int64, safeKey []byte) (hook.Decryptor, error) {
cipher := mustGetCipher()
const (
initialBackoff = 100 * time.Millisecond
maxBackoff = 3 * time.Second
backoffFactor = 2.0
)
backoff := initialBackoff
attempt := 0
for {
attempt++
decryptor, err := cipher.GetDecryptor(ezID, collectionID, safeKey)
if err == nil {
return decryptor, nil
}
// If it's NOT a KMS key invalid error, fail immediately (non-retriable)
if !isKmsKeyInvalidError(err) {
log.Error("failed to get decryptor with non-retriable error",
zap.Int64("ezID", ezID),
zap.Int64("collectionID", collectionID),
zap.Int("attempt", attempt),
zap.Error(err))
return nil, err
}
// KMS key invalid error - log and retry
log.Warn("KMS key invalid, will retry",
zap.Int64("ezID", ezID),
zap.Int64("collectionID", collectionID),
zap.Int("attempt", attempt),
zap.Duration("backoff", backoff),
zap.Error(err))
time.Sleep(backoff)
// Exponential backoff with max cap
backoff = time.Duration(float64(backoff) * backoffFactor)
if backoff > maxBackoff {
backoff = maxBackoff
}
}
}
// CipherConfig is the configuration for cipher that is used to encrypt and decrypt messages.
type CipherConfig struct {
// EzID is the encryption zone ID.
EzID int64
// Collection ID
CollectionID int64
}