The Additional Authenticated Data (AAD) is an input to an Authenticated Encryption operation. The AAD is integrity protected but not encrypted.
Its value can be any string you want that is needed by your application. With the example below, we will add a dummy AAD:
Note: when the AAD is set, the Compact Serialization mode is not available.
When you need to encrypt the same payload for several audiences, you may want to do it at once. The JWE Builder supports multiple recipients.
With the example below, we will create an encrypted token for three different recipients using three different key encryption algorithms.
Important notes:
The content encryption algorithm MUST be the same for all recipients.
The Key Management Modes of the key encryption algorithms MUST be compatible (see table below).
Note: when an unprotected header is set, the Compact Serialization mode is not available.
Each Key Encryption Algorithm has its own Key Management Mode.
As well as the , the encrypted tokens also have unprotected header. But with one difference: there are two unprotected headers:
Shared unprotected header applicable to all recipients.
Per-recipient unprotected header.
With the example below, we will create an encrypted token for two recipient and some unprotected header parameters:
The variable $jwe
will be a valid JWE object built for two recipients. The unprotected header parameter author
is applicable to the whole token while message
and description
are available only for the first and second recipient respectively.
Note: when an unprotected header is set, the Compact Serialization mode is not available.
Algorithm Key Management Mode
Key Encryption
Key Wrapping
Direct Key Agreement
Key Agreement with Key Wrapping
Direct Encryption
dir
X
A128KW
X
A192KW
X
A256KW
X
ECDH-ES
X
ECDH-ES+A128KW
X
ECDH-ES+A192KW
X
ECDH-ES+A256KW
X
PBES2-HS256+A128KW
X
PBES2-HS384+A192KW
X
PBES2-HS512+A256KW
X
RSA1_5
X
RSA-OAEP
X
RSA-OAEP-256
X
A128GCMKW
X
A192GCMKW
X
A256GCMKW
X
Key Management Mode
Key Encryption
Key Wrapping
Direct Key Agreement
Key Agreement with Key Wrapping
Direct Encryption
Key Encryption
YES
YES
NO
YES
NO
Key Wrapping
YES
YES
NO
YES
NO
Direct Key Agreement
NO
NO
NO
NO
NO
Key Agreement with Key Wrapping
YES
YES
NO
NO
NO
Direct Encryption
NO
NO
NO
NO
NO