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Appendix A. JWS Examples

Appendix A. JWS Examples​

This appendix provides several examples of JWSs. While the first three examples all represent JSON Web Tokens (JWTs) [JWT], the payload can be any octet sequence, as shown in Appendix A.4.

A.1 Example JWS Using HMAC SHA-256​

A.1.1 Encoding​

The JWS Protected Header declares that the data structure is a JWT and the JWS Signing Input is secured using the HMAC SHA-256 algorithm:

{"typ":"JWT",
 "alg":"HS256"}

The JWS Payload is:

{"iss":"joe",
 "exp":1300819380,
 "http://example.com/is_root":true}

The complete JWS using the JWS Compact Serialization (with line breaks for display purposes only):

eyJ0eXAiOiJKV1QiLA0KICJhbGciOiJIUzI1NiJ9
.
eyJpc3MiOiJqb2UiLA0KICJleHAiOjEzMDA4MTkzODAsDQogImh0dHA6Ly9leGFt
cGxlLmNvbS9pc19yb290Ijp0cnVlfQ
.
dBjftJeZ4CVP-mB92K27uhbUJU1p1r_wW1gFWFOEjXk

A.1.2 Validating​

Since the "alg" Header Parameter is "HS256", we validate the HMAC SHA-256 value contained in the JWS Signature by repeating the HMAC computation and comparing the results.

A.2 Example JWS Using RSASSA-PKCS1-v1_5 SHA-256​

A.2.1 Encoding​

The JWS Protected Header for this example:

{"alg":"RS256"}

This example uses an RSA private key for signing. The complete JWS representation is produced following the same encoding process.

A.2.2 Validating​

The RSASSA-PKCS1-v1_5 SHA-256 digital signature is validated by passing the public key, the JWS Signature, and the JWS Signing Input to an RSA signature verifier configured to use SHA-256.

A.3 Example JWS Using ECDSA P-256 SHA-256​

A.3.1 Encoding​

The JWS Protected Header:

{"alg":"ES256"}

This example uses an Elliptic Curve P-256 key for signing with SHA-256.

A.3.2 Validating​

The ECDSA P-256 SHA-256 digital signature is validated using the EC public key and the signature split into R and S components.

A.4 Example JWS Using ECDSA P-521 SHA-512​

A.4.1 Encoding​

The JWS Protected Header:

{"alg":"ES512"}

The JWS Payload for this example is the ASCII string "Payload".

A.4.2 Validating​

The ECDSA P-521 SHA-512 digital signature is validated using the EC public key on the P-521 curve.

A.5 Example Unsecured JWS​

An example JWS with no integrity protection (using "alg":"none"). This is only suitable for situations where the payload integrity is protected by other means.

A.6 Example JWS Using General JWS JSON Serialization​

A.6.1 JWS Per-Signature Protected Headers​

A.6.2 JWS Per-Signature Unprotected Headers​

A.6.3 Complete JOSE Header Values​

A.6.4 Complete JWS JSON Serialization Representation​

This example demonstrates the general JWS JSON Serialization syntax with multiple signatures.

A.7 Example JWS Using Flattened JWS JSON Serialization​

This example demonstrates the flattened JWS JSON Serialization syntax optimized for the single signature case.

Note: For complete details of all examples including exact octet sequences, key values, and step-by-step encoding/validation processes, please refer to the official RFC 7515 document at https://www.rfc-editor.org/rfc/rfc7515.txt.