JWE Class

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Create, Encrypt and Decrypt JSON Web Encryption (JWE) messages.

Syntax

ipworksencrypt.jwe()

Remarks

The JWE class supports encrypting and decrypting JSON Web Encryption (JWE) messages.

Specify any payload via input properties and use Encrypt to create a JWE message using a variety of algorithms including ECDH, RSA, and AES. Use Decrypt to decrypt the payload of any received JWE message. The following algorithms are supported:

• RSA1_5
• RSA-OAEP
• RSA-OAEP-256
• A128KW
• A192KW
• A256KW
• Direct
• ECDH-ES
• ECDH-ES+A128KW
• ECDH-ES+A192KW
• ECDH-ES+A256KW
• A128GCMKW
• A192GCMKW
• A256GCMKW
• PBES2-HS256+A128KW
• PBES2-HS384+A192KW
• PBES2-HS512+A256KW

See EncryptionAlgorithm for more details about supported algorithms.

Encrypting

The Encrypt method may be used to encrypt a payload with a variety of algorithms. JSON Web Encryption (JWE) is performed by first generating a random key used to encrypt the content. The content encryption key is used to encrypt the content using the algorithm specified by ContentEncryptionAlgorithm. The content encryption key is then encrypted itself using the algorithm specified by EncryptionAlgorithm. The content encryption key is not directly exposed in the API as it is randomly generated.

After calling this method the compact serialized JWE string is written to the specified output location. For instance:

eyJhbGciOiJBMjU2R0NNS1ciLCJlbmMiOiJBMTI4Q0JDLUhTMjU2IiwiaXYiOiJMa0tNeTZ5Qlpfbzh6QW92IiwidGFnIjoiSmpMTkRsV3l3bWt3V2pMa0NLU0xxQSJ9.wiwySYm6fXZre-3IdT1tb_02KMQDrMICwUawVf7Gjhc.k84s7ne8J41QnA5BQ31k_A.kjIveRjjNYV4x92CVE9Agw.uAygkyeO2KWeFQIy9JLU0A

The class is agnostic of the payload that is encrypted. Any value may be encrypted. KeyId may be set to include an identifier to help the receiving party identify the key or certificate used to encrypt the data. The following properties are applicable when calling this method:

• EncryptionAlgorithm (required)
• Key (conditional - required for AES)
• KeyPassword (conditional - required for PBES)
• Certificate (conditional - required for ECDH and RSA)
• ContentEncryptionAlgorithm
• CompressionAlgorithm
• HeaderParams
• Overwrite

Input and Output Properties

The class will determine the source and destination of the input and output based on which properties are set.

The order in which the input properties are checked is as follows:

• InputFile
• InputMessage

When a valid source is found, the search stops. The order in which the output properties are checked is as follows:

• OutputFile
• OutputMessage: The output data is written to this property if no other destination is specified.

Notes for AES Algorithms (A128KW, A192KW, A256KW, A128GCMKW, A192GCMKW, A256GCMKW)

When EncryptionAlgorithm is set to a AES algorithm Key must be set to a key of appropriate length for the algorithm. For instance a 256 bit key would be used for A256KW.

The example below uses the EzRand class to generate a key, but the key may be created using any method. The key must be known by both parties in order for encryption and decryption to take place.

//Generate a 256 bit (32 byte) key Ezrand rand = new Ezrand(); rand.RandBytesLength = 32; rand.GetNextBytes(); byte[] key = rand.RandBytesB; //Encrypt the payload using A256KW Jwe jwe = new Jwe(); jwe.KeyB = key; jwe.InputMessage = "test data"; jwe.EncryptionAlgorithm = JweEncryptionAlgorithms.eaA256KW; jwe.Encrypt(); string encryptedData = jwe.OutputMessage;

To use an existing AES key provide the bytes to the Key property. For instance:

byte[] key = new byte[] { 164, 60, 194, 0, 161, 189, 41, 38, 130, 89, 141, 164, 45, 170, 159, 209, 69, 137, 243, 216, 191, 131, 47, 250, 32, 107, 231, 117, 37, 158, 225, 234 }; //Encrypt the payload using A256KW Jwe jwe = new Jwe(); jwe.KeyB = key; jwe.InputMessage = "test data"; jwe.EncryptionAlgorithm = JweEncryptionAlgorithms.eaA256KW; jwe.Encrypt(); string encryptedData = jwe.OutputMessage;

Notes for RSA Algorithms (RSA1_5, RSA-OEAP, RSA-OAEP-256)

The RSA based algorithms use asymmetric encryption. Encrypting is done with a public key and decryption is done with a private key. The public certificate should be in PEM (base64) format. For instance:

Jwe jwe = new Jwe(); jwe.Certificate = new Certificate("..\\recipient.cer"); jwe.InputMessage = "test data"; jwe.EncryptionAlgorithm = JweEncryptionAlgorithms.eaRSA_OAEP; jwe.Encrypt(); string encryptedData = jwe.OutputMessage;

Notes for ECDH Algorithms (ECDH-ES, ECDH-ES+A128KW, ECDH-ES+A192KW, ECDH-ES+A256KW)

ECDH algorithms require a valid ECC public key to encrypt the message. If the key was originally created with the ECC class the PEM encoded PublicKey may be used directly with the Certificate property. An example PEM encoded public certificate created by the ECC component:

-----BEGIN PUBLIC KEY-----
MIIBMjCB7AYHKoZIzj0CATCB4AIBATAsBgcqhkjOPQEBAiEA/////wAAAAEAAAAAAAAAAAAA
AAD///////////////8wRAQg/////wAAAAEAAAAAAAAAAAAAAAD///////////////wEIFrG
NdiqOpPns+u9VXaYhrxlHQawzFOw9jvOPD4n0mBLBEEEaxfR8uEsQkf4vOblY6RA8ncDfYEt
6zOg9KE5RdiYwpZP40Li/hp/m47n60p8D54WK84zV2sxXs7LtkBoN79R9QIhAP////8AAAAA
//////////+85vqtpxeehPO5ysL8YyVRAgEBA0EEIC5rbLp11Mnz6cBXLLriaDIov3rm8RAY
x/OR0bOKiff0cQy+sLVaxjseqFk/+Xvl4ORSv5Z6HdHv5GyEpA0UoA==
-----END PUBLIC KEY-----

Jwe jwe = new Jwe(); jwe.Certificate = new Certificate(CertStoreTypes.cstPublicKeyFile, pubKeyFile, "", "*"); jwe.InputMessage = "test data"; jwe.EncryptionAlgorithm = JweEncryptionAlgorithms.eaECDH_ES_A256KW; jwe.Encrypt(); string encryptedData = jwe.OutputMessage;

To use an ECC public key created by other means the ECC class may be used to import the key parameters. Populate the Rx and Ry properties of the ECC component first to obtain the PEM formatted public key. For instance:

byte[] x_bytes = new byte[] { 171, 170, 196, 151, 94, 196, 231, 12, 128, 232, 17, 61, 45, 105, 41, 209, 192, 187, 112, 242, 110, 178, 95, 240, 36, 55, 83, 171, 190, 176, 78, 13 }; byte[] y_bytes = new byte[] { 197, 75, 134, 245, 245, 28, 199, 9, 7, 117, 1, 54, 49, 178, 135, 252, 62, 89, 35, 180, 117, 80, 231, 23, 110, 250, 28, 124, 219, 253, 224, 156 }; Ecc ecc = new Ecc(); ecc.Key.RxB = x_bytes; ecc.Key.RyB = y_bytes; string pubKey = ecc.Key.PublicKey; Jwe jwe = new Jwe(); jwe.Certificate = new Certificate(CertStoreTypes.cstPublicKeyFile, pubKey, "", "*"); jwe.InputMessage = "test data"; jwe.EncryptionAlgorithm = JweEncryptionAlgorithms.eaECDH_ES_A256KW; jwe.Encrypt(); string encryptedData = jwe.OutputMessage;

Notes for PBES Algorithms (PBES2-HS256+A128KW, PBES2-HS384+A192KW, PBES2-HS512+A256KW

PBES algorithms derive a content encryption key from the KeyPassword property. Set KeyPassword to a shared secret.

Jwe jwe = new Jwe(); jwe.KeyPassword = "secret"; jwe.InputMessage = "test data"; jwe.EncryptionAlgorithm = JweEncryptionAlgorithms.eaPBES2_HS512_A256KW; jwe.Encrypt(); string encryptedData = jwe.OutputMessage;

Notes for Direct Shared Keys

When EncryptionAlgorithm is set to Direct the Key property must be set to a valid symmetric key that will be used directly by the ContentEncryptionAlgorithm. In this case a content encryption key is not generated randomly, the Key is used instead. The length of the specified Key must be valid for the selected ContentEncryptionAlgorithm. For instance:

//Generate a 256 bit (32 byte) key Ezrand rand = new Ezrand(); rand.RandBytesLength = 32; rand.GetNextBytes(); byte[] key = rand.RandBytesB; Jwe jwe = new Jwe(); jwe.EncryptionAlgorithm = JweEncryptionAlgorithms.eaDir; jwe.ContentEncryptionAlgorithm = JweContentEncryptionAlgorithms.ceaA256GCM; jwe.KeyB = key; jwe.InputMessage = "test data"; jwe.Encrypt(); string encryptedData = jwe.OutputMessage;

Decrypting

The Decrypt method may be used to decrypt a received JWE message. Before calling the Decrypt method set InputMessage or InputFile to a valid compact serialized JWE string. For instance:

eyJhbGciOiJBMjU2R0NNS1ciLCJlbmMiOiJBMTI4Q0JDLUhTMjU2IiwiaXYiOiJMa0tNeTZ5Qlpfbzh6QW92IiwidGFnIjoiSmpMTkRsV3l3bWt3V2pMa0NLU0xxQSJ9.wiwySYm6fXZre-3IdT1tb_02KMQDrMICwUawVf7Gjhc.k84s7ne8J41QnA5BQ31k_A.kjIveRjjNYV4x92CVE9Agw.uAygkyeO2KWeFQIy9JLU0A

The type and format of the private key depends on the algorithm used to encrypt the data. The following table summarizes the relationship:

If the correct Key or Certificate is not known ahead of time the KeyId parameter of the RecipientInfo event may be used to identify the correct key.

If this method returns without error decryption was successful. If decryption fails then this method . After calling this method the payload will be present in the OutputMessage or file specified by OutputFile and the HeaderParams property will contain the headers. Headers of the parsed message are also available through the HeaderParam event.

The following properties are applicable when calling this method:

• Certificate (conditional - required for RSA and ECDH)
• Key (conditional - required for AES)
• ContentEncryptionAlgorithm (only if StrictValidation is True)
• EncryptionAlgorithm (only if StrictValidation is True)
• HeaderParams
• Overwrite
• StrictValidation

Input and Output Properties

The class will determine the source and destination of the input and output based on which properties are set.

The order in which the input properties are checked is as follows:

• InputFile
• InputMessage

When a valid source is found, the search stops. The order in which the output properties are checked is as follows:

• OutputFile
• OutputMessage: The output data is written to this property if no other destination is specified.

Notes for AES Algorithms (A128KW, A192KW, A256KW, A128GCMKW, A192GCMKW, A256GCMKW)

To decrypt messages that use AES encryption Key must be set to a key of appropriate length for the algorithm. For instance a 256 bit key would be used for A256KW.

The key must be known by both parties in order for encryption and decryption to take place.

byte[] key = new byte[] { 164, 60, 194, 0, 161, 189, 41, 38, 130, 89, 141, 164, 45, 170, 159, 209, 69, 137, 243, 216, 191, 131, 47, 250, 32, 107, 231, 117, 37, 158, 225, 234 }; Jwe jwe = new Jwe(); jwe.KeyB = key; jwe.InputMessage = encryptedData; jwe.Decrypt(); string decryptedData = jwe.OutputMessage;

Notes for RSA Algorithms (RSA1_5, RSA-OEAP, RSA-OAEP-256)

The RSA based algorithms use asymmetric encryption. Encrypting is done with a public key and decryption is done with a private key. The certificate with private key must be specified. For instance:

Jwe jwe = new Jwe(); jwe.Certificate = new Certificate(CertStoreTypes.cstPFXFile, "..\\jwt.pfx", "password", "*"); jwe.InputMessage = encryptedData; jwe.Decrypt(); string decryptedData = jwe.OutputMessage;

Notes for ECDH Algorithms (ECDH-ES, ECDH-ES+A128KW, ECDH-ES+A192KW, ECDH-ES+A256KW)

ECDH algorithms require a valid ECC private key to decrypt the message. If the key was originally created with the ECC class the PEM encoded PrivateKey may be used directly with the Certificate property.

Jwe jwe = new Jwe(); jwe.Certificate = new Certificate(CertStoreTypes.cstPEMKeyFile, privKeyFile, "", "*"); jwe.InputMessage = encryptedData; jwe.Decrypt(); string decryptedData = jwe.OutputMessage;

To use an ECC private key created by other means the ECC class may be used to import the key parameters. Populate the Rx, Ry, and KB properties of the ECC component first to obtain the PEM formatted public key. For instance:

Ecc ecc = new Ecc(); byte[] x_bytes = new byte[] { 171, 170, 196, 151, 94, 196, 231, 12, 128, 232, 17, 61, 45, 105, 41, 209, 192, 187, 112, 242, 110, 178, 95, 240, 36, 55, 83, 171, 190, 176, 78, 13 }; byte[] y_bytes = new byte[] { 197, 75, 134, 245, 245, 28, 199, 9, 7, 117, 1, 54, 49, 178, 135, 252, 62, 89, 35, 180, 117, 80, 231, 23, 110, 250, 28, 124, 219, 253, 224, 156 }; byte[] k_bytes = new byte[] { 81, 65, 201, 24, 235, 249, 162, 148, 169, 150, 109, 181, 61, 238, 145, 122, 31, 30, 151, 94, 239, 90, 222, 217, 63, 103, 54, 2, 176, 232, 248, 168 }; ecc.Key.RxB = x_bytes; ecc.Key.RyB = y_bytes; ecc.Key.KB = k_bytes; string privKey = ecc.Key.PrivateKey; Jwe jwe = new Jwe(); jwe.Certificate = new Certificate(CertStoreTypes.cstPEMKeyBlob, privKey, "", "*"); jwe.InputMessage = encryptedData; jwe.Decrypt(); string decryptedData = jwe.OutputMessage;

Notes for PBES Algorithms (PBES2-HS256+A128KW, PBES2-HS384+A192KW, PBES2-HS512+A256KW

PBES algorithms derive a content encryption key from the KeyPassword property. Set KeyPassword to the shared secret.

Jwe jwe = new Jwe(); jwe.KeyPassword = "secret"; jwe.InputMessage = encryptedData; jwe.Decrypt(); string decryptedData = jwe.OutputMessage;

Notes for Direct Shared Keys

When Direct encryption is used the Key property must be set to a valid symmetric key that will be used directly by the ContentEncryptionAlgorithm. For instance:

byte[] key = new byte[] { 164, 60, 194, 0, 161, 189, 41, 38, 130, 89, 141, 164, 45, 170, 159, 209, 69, 137, 243, 216, 191, 131, 47, 250, 32, 107, 231, 117, 37, 158, 225, 234 }; Jwe jwe = new Jwe(); jwe.KeyB = key; jwe.InputMessage = encryptedData; jwe.Decrypt(); string decryptedData = jwe.OutputMessage;

Other Functionality

In addition to standard encrypting and decrypting the class also supports a variety of other features including:

• Adding custom header parameters with AddHeaderParam
• Enforcing algorithm restrictions when decrypting by setting StrictValidation
• Inspect the JWE headers without decrypting by calling Parse

Property List

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The following is the full list of the properties of the class with short descriptions. Click on the links for further details.

Method List

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The following is the full list of the methods of the class with short descriptions. Click on the links for further details.

Event List

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The following is the full list of the events fired by the class with short descriptions. Click on the links for further details.

Config Settings

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The following is a list of config settings for the class with short descriptions. Click on the links for further details.

JWE.Certificate Property

The certificate used for encryption or decryption.

Syntax

getCertificate(): Certificate;
setCertificate(certificate: Certificate): void;

Default Value

Remarks

This property specifies a certificate for encryption or decryption.

When calling Encrypt and EncryptionAlgorithm is set to an RSA or ECDH algorithm this property must be set to a public certificate of the recipient.

When calling Decrypt and the message was encrypted using an RSA or ECDH EncryptionAlgorithm this property specifies the certificate with private key used to decrypt the message.

Please refer to the Certificate type for a complete list of fields.

JWE.ContentEncryptionAlgorithm Property

The algorithm used to encrypt the content.

Syntax

getContentEncryptionAlgorithm(): JWEContentEncryptionAlgorithms;
setContentEncryptionAlgorithm(contentEncryptionAlgorithm: JWEContentEncryptionAlgorithms): void;

enum JWEContentEncryptionAlgorithms {
  ceaA128CBC_HS256,
  ceaA192CBC_HS384,
  ceaA256CBC_HS512,
  ceaA128GCM,
  ceaA192GCM,
  ceaA256GCM
}

Default Value

0

Remarks

This property specifies the algorithm used to encrypt the content.

The following values are supported.

JWE.EncryptionAlgorithm Property

The key encryption algorithm.

Syntax

getEncryptionAlgorithm(): JWEEncryptionAlgorithms;
setEncryptionAlgorithm(encryptionAlgorithm: JWEEncryptionAlgorithms): void;

enum JWEEncryptionAlgorithms {
  eaRSA1_5,
  eaRSA_OAEP,
  eaRSA_OAEP_256,
  eaA128KW,
  eaA192KW,
  eaA256KW,
  eaDir,
  eaECDH_ES,
  eaECDH_ES_A128KW,
  eaECDH_ES_A192KW,
  eaECDH_ES_A256KW,
  eaA128GCMKW,
  eaA192GCMKW,
  eaA256GCMKW,
  eaPBES2_HS256_A128KW,
  eaPBES2_HS384_A192KW,
  eaPBES2_HS512_A256KW
}

Default Value

0

Remarks

This property specifies the algorithm used to encrypt the randomly generated content encryption key.

When using an AES algorithm Key must be specified. When using an RSA or ECDH algorithm Certificate must be specified. When using a PBES algorithm KeyPassword must be specified;. Possible values are:

When set to an ECDH algorithm the following settings are also applicable:

• PartyUInfo
• PartyVInfo

When set to a PBES algorithm the following settings are also applicable:

• PBES2Count
• PBES2SaltLength

JWE.HeaderParams Property

The JOSE header parameters.

Syntax

getHeaderParams(): HeaderParamList;
setHeaderParams(headerParams: HeaderParamList): void;

Default Value

Remarks

This property specifies the JOSE header parameters. This may be populated before calling Sign or Encrypt. This is populated with the parsed header values after calling Verify, Decrypt, or Parse.

This property is not available at design time.

Please refer to the HeaderParam type for a complete list of fields.

JWE.InputFile Property

The file to process.

Syntax

getInputFile(): string;
setInputFile(inputFile: string): void;

Default Value

""

Remarks

This property specifies the file to be processed. Set this property to the full or relative path to the file which will be processed.

Input and Output Properties

The class will determine the source and destination of the input and output based on which properties are set.

The order in which the input properties are checked is as follows:

• InputFile
• InputMessage

When a valid source is found, the search stops. The order in which the output properties are checked is as follows:

• OutputFile
• OutputMessage: The output data is written to this property if no other destination is specified.

JWE.InputMessage Property

The message to process.

Syntax

getInputMessage(): Uint8Array;
setInputMessage(inputMessage: Uint8Array): void;

Default Value

""

Remarks

This property specifies the message to be processed.

Input and Output Properties

The class will determine the source and destination of the input and output based on which properties are set.

The order in which the input properties are checked is as follows:

• InputFile
• InputMessage

When a valid source is found, the search stops. The order in which the output properties are checked is as follows:

• OutputFile
• OutputMessage: The output data is written to this property if no other destination is specified.

JWE.Key Property

The secret key for the AES algorithm.

Syntax

getKey(): Uint8Array;
setKey(key: Uint8Array): void;

Default Value

""

Remarks

This property specifies the key used for AES encryption and decryption.

When EncryptionAlgorithm is set to an AES algorithm this property must hold the symmetric key used for encryption and decryption. The size of the key must match the size of the algorithm. For instance when selecting the algorithm A256GCMKW (AES 256) the size of the key must also be 256 bits (32 bytes).

In the case where EncryptionAlgorithm is set to Direct this key is used directly with the algorithm specified by ContentEncryptionAlgorithm and must be an appropriate size for the selected ContentEncryptionAlgorithm.

JWE.KeyId Property

The Id of the key used to encrypt the message.

Syntax

getKeyId(): string;
setKeyId(keyId: string): void;

Default Value

""

Remarks

This property optionally specifies the Id of the key used to encrypt the message.

Any string value may be supplied here to help the other party identify the key used to encrypt the message. This may be set before calling the Encrypt method.

JWE.KeyPassword Property

The key password used in the PBES algorithm.

Syntax

getKeyPassword(): string;
setKeyPassword(keyPassword: string): void;

Default Value

""

Remarks

This property specifies the key password used to derive a key when using a PBES EncryptionAlgorithm.

This is only applicable to PBES algorithms and must be set before calling Encrypt or Decrypt.

JWE.OutputFile Property

The output file when encrypting or decrypting.

Syntax

getOutputFile(): string;
setOutputFile(outputFile: string): void;

Default Value

""

Remarks

This property specifies the file to which the output will be written when Encrypt or Decrypt is called. This may be set to an absolute or relative path.

This property is only applicable to Encrypt and Decrypt.

Input and Output Properties

The class will determine the source and destination of the input and output based on which properties are set.

The order in which the input properties are checked is as follows:

• InputFile
• InputMessage

When a valid source is found, the search stops. The order in which the output properties are checked is as follows:

• OutputFile
• OutputMessage: The output data is written to this property if no other destination is specified.

JWE.OutputMessage Property

The output message after processing.

Syntax

getOutputMessage(): Uint8Array;

Default Value

""

Remarks

This property will be populated with the output from the operation if OutputFile is not set.

Input and Output Properties

The class will determine the source and destination of the input and output based on which properties are set.

The order in which the input properties are checked is as follows:

• InputFile
• InputMessage

When a valid source is found, the search stops. The order in which the output properties are checked is as follows:

• OutputFile
• OutputMessage: The output data is written to this property if no other destination is specified.

This property is read-only and not available at design time.

JWE.Overwrite Property

Indicates whether or not the class should overwrite files.

Syntax

isOverwrite(): boolean;
setOverwrite(overwrite: boolean): void;

Default Value

FALSE

Remarks

This property indicates whether or not the class will overwrite OutputFile. If Overwrite is False, an error will be thrown whenever OutputFile exists before an operation. The default value is False.

JWE.addHeaderParam Method

Adds additional header parameters.

Syntax

async jwe.addHeaderParam(name : string, value : string, dataType : number): Promise<void>

Remarks

This method is used to add additional header parameters before calling Encrypt.

The Name and Value parameters define the name and value of the parameter respectively. The DataType parameter specifies the JSON data type of the value. Possible values for DataType are:

• 0 (Object)
• 1 (Array)
• 2 (String)
• 3 (Number)
• 4 (Bool)
• 5 (Null)

To add additional parameters to the JOSE header use this method. For instance to create this header:

{
	"alg": "A256GCMKW",
	"crit": [
		"exp"
	],
	"enc": "A128CBC-HS256",
	"exp": 12345687,
	"iv": "SFZ9o0KKN8qF8yod",
	"tag": "tREHGKuViLo7s3QpRTulkg",
	"type": "JWT"
}

The following code can be used:

Jwe jwe = new Jwe(); jwe.EncryptionAlgorithm = JweEncryptionAlgorithms.eaA256GCMKW; jwe.KeyB = key; jwe.AddHeaderParam("type", "JWT", 2); jwe.AddHeaderParam("crit", "[\"exp\"]", 1); jwe.AddHeaderParam("exp", "12345687", 3); jwe.InputMessage = "test"; jwe.Encrypt(); string encryptedData = jwe.OutputMessage;

Note: When calling Encrypt the class will automatically add headers based on the selected EncryptionAlgorithm and other properties that may be set.

Parameters Automatically Set:

JWE.config Method

Sets or retrieves a configuration setting.

Syntax

async jwe.config(configurationString : string): Promise<string>

Remarks

Config is a generic method available in every class. It is used to set and retrieve configuration settings for the class.

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, access to these internal properties is provided through the Config method.

To set a configuration setting named PROPERTY, you must call Config("PROPERTY=VALUE"), where VALUE is the value of the setting expressed as a string. For boolean values, use the strings "True", "False", "0", "1", "Yes", or "No" (case does not matter).

To read (query) the value of a configuration setting, you must call Config("PROPERTY"). The value will be returned as a string.

JWE.decrypt Method

Decrypts the payload.

Syntax

async jwe.decrypt(): Promise<void>

Remarks

This method decrypts the input data.

Before calling the Decrypt method set InputMessage or InputFile to a valid compact serialized JWE string. For instance:

eyJhbGciOiJBMjU2R0NNS1ciLCJlbmMiOiJBMTI4Q0JDLUhTMjU2IiwiaXYiOiJMa0tNeTZ5Qlpfbzh6QW92IiwidGFnIjoiSmpMTkRsV3l3bWt3V2pMa0NLU0xxQSJ9.wiwySYm6fXZre-3IdT1tb_02KMQDrMICwUawVf7Gjhc.k84s7ne8J41QnA5BQ31k_A.kjIveRjjNYV4x92CVE9Agw.uAygkyeO2KWeFQIy9JLU0A

The type and format of the private key depends on the algorithm used to encrypt the data. The following table summarizes the relationship:

If the correct Key or Certificate is not known ahead of time the KeyId parameter of the RecipientInfo event may be used to identify the correct key.

If this method returns without error decryption was successful. If decryption fails then this method . After calling this method the payload will be present in the OutputMessage or file specified by OutputFile and the HeaderParams property will contain the headers. Headers of the parsed message are also available through the HeaderParam event.

The following properties are applicable when calling this method:

• Certificate (conditional - required for RSA and ECDH)
• Key (conditional - required for AES)
• ContentEncryptionAlgorithm (only if StrictValidation is True)
• EncryptionAlgorithm (only if StrictValidation is True)
• HeaderParams
• Overwrite
• StrictValidation

Input and Output Properties

The class will determine the source and destination of the input and output based on which properties are set.

The order in which the input properties are checked is as follows:

• InputFile
• InputMessage

When a valid source is found, the search stops. The order in which the output properties are checked is as follows:

• OutputFile
• OutputMessage: The output data is written to this property if no other destination is specified.

Notes for AES Algorithms (A128KW, A192KW, A256KW, A128GCMKW, A192GCMKW, A256GCMKW)

To decrypt messages that use AES encryption Key must be set to a key of appropriate length for the algorithm. For instance a 256 bit key would be used for A256KW.

The key must be known by both parties in order for encryption and decryption to take place.

byte[] key = new byte[] { 164, 60, 194, 0, 161, 189, 41, 38, 130, 89, 141, 164, 45, 170, 159, 209, 69, 137, 243, 216, 191, 131, 47, 250, 32, 107, 231, 117, 37, 158, 225, 234 }; Jwe jwe = new Jwe(); jwe.KeyB = key; jwe.InputMessage = encryptedData; jwe.Decrypt(); string decryptedData = jwe.OutputMessage;

Notes for RSA Algorithms (RSA1_5, RSA-OEAP, RSA-OAEP-256)

The RSA based algorithms use asymmetric encryption. Encrypting is done with a public key and decryption is done with a private key. The certificate with private key must be specified. For instance:

Jwe jwe = new Jwe(); jwe.Certificate = new Certificate(CertStoreTypes.cstPFXFile, "..\\jwt.pfx", "password", "*"); jwe.InputMessage = encryptedData; jwe.Decrypt(); string decryptedData = jwe.OutputMessage;

Notes for ECDH Algorithms (ECDH-ES, ECDH-ES+A128KW, ECDH-ES+A192KW, ECDH-ES+A256KW)

ECDH algorithms require a valid ECC private key to decrypt the message. If the key was originally created with the ECC class the PEM encoded PrivateKey may be used directly with the Certificate property.

Jwe jwe = new Jwe(); jwe.Certificate = new Certificate(CertStoreTypes.cstPEMKeyFile, privKeyFile, "", "*"); jwe.InputMessage = encryptedData; jwe.Decrypt(); string decryptedData = jwe.OutputMessage;

To use an ECC private key created by other means the ECC class may be used to import the key parameters. Populate the Rx, Ry, and KB properties of the ECC component first to obtain the PEM formatted public key. For instance:

Ecc ecc = new Ecc(); byte[] x_bytes = new byte[] { 171, 170, 196, 151, 94, 196, 231, 12, 128, 232, 17, 61, 45, 105, 41, 209, 192, 187, 112, 242, 110, 178, 95, 240, 36, 55, 83, 171, 190, 176, 78, 13 }; byte[] y_bytes = new byte[] { 197, 75, 134, 245, 245, 28, 199, 9, 7, 117, 1, 54, 49, 178, 135, 252, 62, 89, 35, 180, 117, 80, 231, 23, 110, 250, 28, 124, 219, 253, 224, 156 }; byte[] k_bytes = new byte[] { 81, 65, 201, 24, 235, 249, 162, 148, 169, 150, 109, 181, 61, 238, 145, 122, 31, 30, 151, 94, 239, 90, 222, 217, 63, 103, 54, 2, 176, 232, 248, 168 }; ecc.Key.RxB = x_bytes; ecc.Key.RyB = y_bytes; ecc.Key.KB = k_bytes; string privKey = ecc.Key.PrivateKey; Jwe jwe = new Jwe(); jwe.Certificate = new Certificate(CertStoreTypes.cstPEMKeyBlob, privKey, "", "*"); jwe.InputMessage = encryptedData; jwe.Decrypt(); string decryptedData = jwe.OutputMessage;

Notes for PBES Algorithms (PBES2-HS256+A128KW, PBES2-HS384+A192KW, PBES2-HS512+A256KW

PBES algorithms derive a content encryption key from the KeyPassword property. Set KeyPassword to the shared secret.

Jwe jwe = new Jwe(); jwe.KeyPassword = "secret"; jwe.InputMessage = encryptedData; jwe.Decrypt(); string decryptedData = jwe.OutputMessage;

Notes for Direct Shared Keys

When Direct encryption is used the Key property must be set to a valid symmetric key that will be used directly by the ContentEncryptionAlgorithm. For instance:

byte[] key = new byte[] { 164, 60, 194, 0, 161, 189, 41, 38, 130, 89, 141, 164, 45, 170, 159, 209, 69, 137, 243, 216, 191, 131, 47, 250, 32, 107, 231, 117, 37, 158, 225, 234 }; Jwe jwe = new Jwe(); jwe.KeyB = key; jwe.InputMessage = encryptedData; jwe.Decrypt(); string decryptedData = jwe.OutputMessage;

JWE.encrypt Method

Encrypts the payload with the specified algorithms.

Syntax

async jwe.encrypt(): Promise<void>

Remarks

This method encrypts the input data using the specified algorithms.

JSON Web Encryption (JWE) is performed by first generating a random key used to encrypt the content. The content encryption key is used to encrypt the content using the algorithm specified by ContentEncryptionAlgorithm. The content encryption key is then encrypted itself using the algorithm specified by EncryptionAlgorithm. The content encryption key is not directly exposed in the API as it is randomly generated.

After calling this method the compact serialized JWE string is written to the specified output location. For instance:

eyJhbGciOiJBMjU2R0NNS1ciLCJlbmMiOiJBMTI4Q0JDLUhTMjU2IiwiaXYiOiJMa0tNeTZ5Qlpfbzh6QW92IiwidGFnIjoiSmpMTkRsV3l3bWt3V2pMa0NLU0xxQSJ9.wiwySYm6fXZre-3IdT1tb_02KMQDrMICwUawVf7Gjhc.k84s7ne8J41QnA5BQ31k_A.kjIveRjjNYV4x92CVE9Agw.uAygkyeO2KWeFQIy9JLU0A

The class is agnostic of the payload that is encrypted. Any value may be encrypted. KeyId may be set to include an identifier to help the receiving party identify the key or certificate used to encrypt the data. The following properties are applicable when calling this method:

• EncryptionAlgorithm (required)
• Key (conditional - required for AES)
• KeyPassword (conditional - required for PBES)
• Certificate (conditional - required for ECDH and RSA)
• ContentEncryptionAlgorithm
• CompressionAlgorithm
• HeaderParams
• Overwrite

Input and Output Properties

The class will determine the source and destination of the input and output based on which properties are set.

The order in which the input properties are checked is as follows:

• InputFile
• InputMessage

When a valid source is found, the search stops. The order in which the output properties are checked is as follows:

• OutputFile
• OutputMessage: The output data is written to this property if no other destination is specified.

Notes for AES Algorithms (A128KW, A192KW, A256KW, A128GCMKW, A192GCMKW, A256GCMKW)

When EncryptionAlgorithm is set to a AES algorithm Key must be set to a key of appropriate length for the algorithm. For instance a 256 bit key would be used for A256KW.

The example below uses the EzRand class to generate a key, but the key may be created using any method. The key must be known by both parties in order for encryption and decryption to take place.

//Generate a 256 bit (32 byte) key Ezrand rand = new Ezrand(); rand.RandBytesLength = 32; rand.GetNextBytes(); byte[] key = rand.RandBytesB; //Encrypt the payload using A256KW Jwe jwe = new Jwe(); jwe.KeyB = key; jwe.InputMessage = "test data"; jwe.EncryptionAlgorithm = JweEncryptionAlgorithms.eaA256KW; jwe.Encrypt(); string encryptedData = jwe.OutputMessage;

To use an existing AES key provide the bytes to the Key property. For instance:

byte[] key = new byte[] { 164, 60, 194, 0, 161, 189, 41, 38, 130, 89, 141, 164, 45, 170, 159, 209, 69, 137, 243, 216, 191, 131, 47, 250, 32, 107, 231, 117, 37, 158, 225, 234 }; //Encrypt the payload using A256KW Jwe jwe = new Jwe(); jwe.KeyB = key; jwe.InputMessage = "test data"; jwe.EncryptionAlgorithm = JweEncryptionAlgorithms.eaA256KW; jwe.Encrypt(); string encryptedData = jwe.OutputMessage;

Notes for RSA Algorithms (RSA1_5, RSA-OEAP, RSA-OAEP-256)

The RSA based algorithms use asymmetric encryption. Encrypting is done with a public key and decryption is done with a private key. The public certificate should be in PEM (base64) format. For instance:

Jwe jwe = new Jwe(); jwe.Certificate = new Certificate("..\\recipient.cer"); jwe.InputMessage = "test data"; jwe.EncryptionAlgorithm = JweEncryptionAlgorithms.eaRSA_OAEP; jwe.Encrypt(); string encryptedData = jwe.OutputMessage;

Notes for ECDH Algorithms (ECDH-ES, ECDH-ES+A128KW, ECDH-ES+A192KW, ECDH-ES+A256KW)

ECDH algorithms require a valid ECC public key to encrypt the message. If the key was originally created with the ECC class the PEM encoded PublicKey may be used directly with the Certificate property. An example PEM encoded public certificate created by the ECC component:

-----BEGIN PUBLIC KEY-----
MIIBMjCB7AYHKoZIzj0CATCB4AIBATAsBgcqhkjOPQEBAiEA/////wAAAAEAAAAAAAAAAAAA
AAD///////////////8wRAQg/////wAAAAEAAAAAAAAAAAAAAAD///////////////wEIFrG
NdiqOpPns+u9VXaYhrxlHQawzFOw9jvOPD4n0mBLBEEEaxfR8uEsQkf4vOblY6RA8ncDfYEt
6zOg9KE5RdiYwpZP40Li/hp/m47n60p8D54WK84zV2sxXs7LtkBoN79R9QIhAP////8AAAAA
//////////+85vqtpxeehPO5ysL8YyVRAgEBA0EEIC5rbLp11Mnz6cBXLLriaDIov3rm8RAY
x/OR0bOKiff0cQy+sLVaxjseqFk/+Xvl4ORSv5Z6HdHv5GyEpA0UoA==
-----END PUBLIC KEY-----

Jwe jwe = new Jwe(); jwe.Certificate = new Certificate(CertStoreTypes.cstPublicKeyFile, pubKeyFile, "", "*"); jwe.InputMessage = "test data"; jwe.EncryptionAlgorithm = JweEncryptionAlgorithms.eaECDH_ES_A256KW; jwe.Encrypt(); string encryptedData = jwe.OutputMessage;

To use an ECC public key created by other means the ECC class may be used to import the key parameters. Populate the Rx and Ry properties of the ECC component first to obtain the PEM formatted public key. For instance:

byte[] x_bytes = new byte[] { 171, 170, 196, 151, 94, 196, 231, 12, 128, 232, 17, 61, 45, 105, 41, 209, 192, 187, 112, 242, 110, 178, 95, 240, 36, 55, 83, 171, 190, 176, 78, 13 }; byte[] y_bytes = new byte[] { 197, 75, 134, 245, 245, 28, 199, 9, 7, 117, 1, 54, 49, 178, 135, 252, 62, 89, 35, 180, 117, 80, 231, 23, 110, 250, 28, 124, 219, 253, 224, 156 }; Ecc ecc = new Ecc(); ecc.Key.RxB = x_bytes; ecc.Key.RyB = y_bytes; string pubKey = ecc.Key.PublicKey; Jwe jwe = new Jwe(); jwe.Certificate = new Certificate(CertStoreTypes.cstPublicKeyFile, pubKey, "", "*"); jwe.InputMessage = "test data"; jwe.EncryptionAlgorithm = JweEncryptionAlgorithms.eaECDH_ES_A256KW; jwe.Encrypt(); string encryptedData = jwe.OutputMessage;

Notes for PBES Algorithms (PBES2-HS256+A128KW, PBES2-HS384+A192KW, PBES2-HS512+A256KW

PBES algorithms derive a content encryption key from the KeyPassword property. Set KeyPassword to a shared secret.

Jwe jwe = new Jwe(); jwe.KeyPassword = "secret"; jwe.InputMessage = "test data"; jwe.EncryptionAlgorithm = JweEncryptionAlgorithms.eaPBES2_HS512_A256KW; jwe.Encrypt(); string encryptedData = jwe.OutputMessage;

Notes for Direct Shared Keys

When EncryptionAlgorithm is set to Direct the Key property must be set to a valid symmetric key that will be used directly by the ContentEncryptionAlgorithm. In this case a content encryption key is not generated randomly, the Key is used instead. The length of the specified Key must be valid for the selected ContentEncryptionAlgorithm. For instance:

//Generate a 256 bit (32 byte) key Ezrand rand = new Ezrand(); rand.RandBytesLength = 32; rand.GetNextBytes(); byte[] key = rand.RandBytesB; Jwe jwe = new Jwe(); jwe.EncryptionAlgorithm = JweEncryptionAlgorithms.eaDir; jwe.ContentEncryptionAlgorithm = JweContentEncryptionAlgorithms.ceaA256GCM; jwe.KeyB = key; jwe.InputMessage = "test data"; jwe.Encrypt(); string encryptedData = jwe.OutputMessage;

JWE.parse Method

Parses the compact serialized JWE string.

Syntax

async jwe.parse(): Promise<void>

Remarks

This method parses, but does not decrypt, the JWE string.

Take care when using this method as no decryption is performed. This method may be helpful in cases where only header information is desired.

If decryption is desired, use Decrypt instead. It is not necessary to call this method before calling Decrypt. Decrypt will both parse and decrypt the message.

When calling this method the headers are parsed. The HeaderParam and RecipientInfo events will fire and the HeaderParams property will be populated.

JWE.reset Method

Resets the class.

Syntax

async jwe.reset(): Promise<void>

Remarks

When called, the class will reset all of its properties to their default values.

JWE.Error Event

Fired when information is available about errors during data delivery.

Syntax

jwe.on('Error', listener: (e: {readonly errorCode: number, readonly description: string}) => void )

Remarks

The Error event is fired in case of exceptional conditions during message processing. Normally the class .

The ErrorCode parameter contains an error code, and the Description parameter contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the Error Codes section.

JWE.HeaderParam Event

Fires once for each JOSE header parameter.

Syntax

jwe.on('HeaderParam', listener: (e: {readonly name: string, readonly value: string, readonly dataType: number}) => void )

Remarks

When Decrypt or Parse is called this event will fire once for each JOSE header parameter.

Name is the name of the parameter.

Value is the value of the parameter.

DataType specifies the JSON data type of the value. Possible values are:

• 0 (Object)
• 1 (Array)
• 2 (String)
• 3 (Number)
• 4 (Bool)
• 5 (Null)

JWE.RecipientInfo Event

Fired with information about the recipient key of the encrypted message.

Syntax

jwe.on('RecipientInfo', listener: (e: {readonly keyId: string, readonly algorithm: string}) => void )

Remarks

This event fires with information about the key used to encrypt the data. This may be used to help identify the Key or Certificate to load in order to decrypt the message. This event fires when Decrypt or Parse is called.

KeyId is the Id of the key as supplied by the entity that created the message. This may be empty.

Algorithm is the encryption algorithm used to encrypt the data.

Certificate Type

This is the digital certificate being used.

Remarks

This type describes the current digital certificate. The certificate may be a public or private key. The fields are used to identify or select certificates.

Fields

Constructors

public Certificate();

public Certificate(String certificateFile);

public Certificate(byte[] encoded);

public Certificate(int storeType, String store, String storePassword, String subject);

public Certificate(int storeType, String store, String storePassword, String subject, String configurationString);

public Certificate(int storeType, String store, String storePassword, byte[] encoded);

public Certificate(int storeType, byte[] store, String storePassword, String subject);

public Certificate(int storeType, byte[] store, String storePassword, String subject, String configurationString);

public Certificate(int storeType, byte[] store, String storePassword, byte[] encoded);

HeaderParam Type

The JOSE header parameter.

Remarks

This type holds the JOSE header parameters. The fields define the name, value, and data type of the parameter.

Fields

Constructors

public HeaderParam();

public HeaderParam(String name, String value);

public HeaderParam(String name, String value, int dataType);

Config Settings (class ipworksencrypt.jwe)

The class accepts one or more of the following configuration settings. Configuration settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, access to these internal properties is provided through the Config method.

JWE Config Settings

Base Config Settings

Trappable Errors (class ipworksencrypt.jwe)

JWE Errors