diff options
| -rw-r--r-- | internal/cryptocore/cryptocore.go | 20 |
1 files changed, 11 insertions, 9 deletions
diff --git a/internal/cryptocore/cryptocore.go b/internal/cryptocore/cryptocore.go index 0848096..0fd401f 100644 --- a/internal/cryptocore/cryptocore.go +++ b/internal/cryptocore/cryptocore.go @@ -23,9 +23,13 @@ const ( // AuthTagLen is the length of a authentication tag in bytes. // All backends use 16 bytes. AuthTagLen = 16 - // Minimum key length + // EME key length + EMEKeyLen = 32 + // Key length for key derivation, or directly for ciphers when not using HKDF + KDFKeyLen = 32 + // Minimum AEAD key length MinKeyLen = 16 - // Maximum key length + // Maximum AEAD key length MaxKeyLen = 32 ) @@ -92,13 +96,11 @@ func New(key []byte, aeadType AEADTypeEnum, IVBitLen int, useHKDF bool) *CryptoC len(key), aeadType, IVBitLen, useHKDF) keyLen := aeadType.KeyLen - if keyLen < MinKeyLen || keyLen > MaxKeyLen { - log.Panicf("Unsupported key length of %d bytes", keyLen) + if !useHKDF && len(key) != keyLen { + log.Panicf("Key length mismatch: got %d bytes, want %d bytes", len(key), keyLen) + } else if useHKDF && len(key) != KDFKeyLen { + log.Panicf("Key length mismatch: got %d bytes, want %d bytes for key derivation", len(key), KDFKeyLen) } - if len(key) < keyLen { - log.Panicf("Unsupported key length of %d bytes", len(key)) - } - key = key[:keyLen] // keys can safely be truncated if IVBitLen != 96 && IVBitLen != 128 && IVBitLen != chacha20poly1305.NonceSizeX*8 { log.Panicf("Unsupported IV length of %d bits", IVBitLen) } @@ -109,7 +111,7 @@ func New(key []byte, aeadType AEADTypeEnum, IVBitLen int, useHKDF bool) *CryptoC { var emeBlockCipher cipher.Block if useHKDF { - emeKey := hkdfDerive(key, hkdfInfoEMENames, keyLen) + emeKey := hkdfDerive(key, hkdfInfoEMENames, EMEKeyLen) emeBlockCipher, err = aes.NewCipher(emeKey) for i := range emeKey { emeKey[i] = 0 |