com.qcloud.cos.internal.crypto

Enum CryptoMode

java.lang.Object

java.lang.Enum<CryptoMode>

com.qcloud.cos.internal.crypto.CryptoMode

All Implemented Interfaces:

Serializable, Comparable<CryptoMode>

public enum CryptoMode
extends Enum<CryptoMode>

Denotes the different cryptographic modes available for securing an COS object via client-side encryption. Crypto mode can be configured via CryptoConfiguration when the COS encryption client is constructed.

Enum Constant Summary

Enum Constants

Enum Constant and Description
AesCbcEncryption Authenticated encryption mode using AES/CBC.
AesCtrEncryption Authenticated encryption mode using AES/CTR.
AuthenticatedEncryption Authenticated encryption mode using AES/GCM, AESWrap, etc.
StrictAuthenticatedEncryption Strictly enforce the use of authenticated encryption via AES/GCM, AESWrap, etc., and will throw security exception if an COS object retrieved is found to be not protected using authenticated encryption.

Method Summary

Modifier and Type	Method and Description
static CryptoMode	valueOf(String name) Returns the enum constant of this type with the specified name.
static CryptoMode[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

AesCtrEncryption

public static final CryptoMode AesCtrEncryption

Authenticated encryption mode using AES/CTR. If you want to encrypt with Java SDK and decrypt with other COS SDKs, you must use this mode.

AesCbcEncryption

public static final CryptoMode AesCbcEncryption

Authenticated encryption mode using AES/CBC.

AuthenticatedEncryption

public static final CryptoMode AuthenticatedEncryption

Authenticated encryption mode using AES/GCM, AESWrap, etc. Please note the limitation on the maximum message size in bytes that can be encrypted under this mode is 2^36-32, or ~64G, due to the security limitation of AES/GCM as recommended by NIST.

StrictAuthenticatedEncryption

public static final CryptoMode StrictAuthenticatedEncryption

Strictly enforce the use of authenticated encryption via AES/GCM, AESWrap, etc., and will throw security exception if an COS object retrieved is found to be not protected using authenticated encryption. This means range-get operation is not supported in this mode, since range-get is not authenticated.

Please note the limitation on the maximum message size in bytes that can be encrypted under this mode is 2^36-32, or ~64G, due to the security limitation of AES/GCM as recommended by NIST.

Method Detail

values

public static CryptoMode[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (CryptoMode c : CryptoMode.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static CryptoMode valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null