One document matched: draft-ietf-jose-json-web-encryption-03.xml
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<rfc category="std" ipr="trust200902" docName="draft-ietf-jose-json-web-encryption-03">
<front>
<title abbrev="JWE">JSON Web Encryption (JWE)</title>
<author fullname="Michael B. Jones" initials="M.B." surname="Jones">
<organization>Microsoft</organization>
<address>
<email>mbj@microsoft.com</email>
<uri>http://self-issued.info/</uri>
</address>
</author>
<author fullname="Eric Rescorla" initials="E." surname="Rescorla">
<organization abbrev="RTFM">RTFM, Inc.</organization>
<address>
<email>ekr@rtfm.com</email>
</address>
</author>
<author fullname="Joe Hildebrand" initials="J." surname="Hildebrand">
<organization abbrev="Cisco">Cisco Systems, Inc.</organization>
<address>
<email>jhildebr@cisco.com</email>
</address>
</author>
<date day="6" month="July" year="2012" />
<area>Security</area>
<workgroup>JOSE Working Group</workgroup>
<keyword>RFC</keyword>
<keyword>Request for Comments</keyword>
<keyword>I-D</keyword>
<keyword>Internet-Draft</keyword>
<keyword>JavaScript Object Notation</keyword>
<keyword>JSON</keyword>
<keyword>JSON Web Token</keyword>
<keyword>JWT</keyword>
<keyword>JSON Web Signature</keyword>
<keyword>JWS</keyword>
<keyword>JSON Web Encryption</keyword>
<keyword>JWE</keyword>
<keyword>JSON Web Key</keyword>
<keyword>JWK</keyword>
<keyword>JSON Web Algorithms</keyword>
<keyword>JWA</keyword>
<abstract>
<t>
JSON Web Encryption (JWE) is a means of representing encrypted
content using JavaScript Object Notation (JSON) data structures.
Cryptographic algorithms and identifiers for use with this
specification are described in the separate
JSON Web Algorithms (JWA) specification.
Related digital signature and MAC capabilities are described
in the separate JSON Web Signature (JWS) specification.
</t>
</abstract>
</front>
<middle>
<section title="Introduction">
<t>
JSON Web Encryption (JWE) is a compact encryption format
intended for space constrained environments such as HTTP
Authorization headers and URI query parameters.
It represents this content using JavaScript Object Notation (JSON)
<xref target="RFC4627"/> data structures.
The JWE cryptographic mechanisms encrypt and provide integrity protection for
arbitrary sequences of bytes.
</t>
<t>
Cryptographic algorithms and identifiers for use with this
specification are described in the separate
JSON Web Algorithms (JWA) <xref target="JWA" /> specification.
Related digital signature and MAC capabilities are described
in the separate JSON Web Signature (JWS) <xref target="JWS" />
specification.
</t>
<section title='Notational Conventions'>
<t>
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL",
"SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY",
and "OPTIONAL" in this document are to be interpreted as
described in
Key words for use in RFCs to Indicate Requirement Levels <xref target='RFC2119' />.
</t>
</section>
</section>
<section title="Terminology">
<t>
<list style="hanging">
<t hangText="JSON Web Encryption (JWE)">
A data structure representing an encrypted message.
The structure consists of four parts: the JWE
Header, the JWE Encrypted Key, the JWE Ciphertext, and
the JWE Integrity Value.
</t>
<t hangText="Plaintext">
The bytes to be encrypted - a.k.a., the message.
The plaintext can contain an arbitrary sequence of bytes.
</t>
<t hangText="Ciphertext">
An encrypted representation of the Plaintext.
</t>
<t hangText="Content Encryption Key (CEK)">
A symmetric key used to encrypt the Plaintext for the
recipient to produce the Ciphertext.
</t>
<t hangText="Content Integrity Key (CIK)">
A key used with a MAC function to ensure the integrity
of the Ciphertext and the parameters used to create it.
</t>
<t hangText="Content Master Key (CMK)">
A key from which the CEK and CIK are derived.
When key wrapping or key encryption are employed, the CMK
is randomly generated and encrypted to the recipient as
the JWE Encrypted Key.
When key agreement is employed, the CMK is the result of
the key agreement algorithm.
</t>
<t hangText="JWE Header">
A string representing a JSON object that describes the
encryption operations applied to create the JWE Encrypted
Key, the JWE Ciphertext, and the JWE Integrity Value.
</t>
<t hangText="JWE Encrypted Key">
When key wrapping or key encryption are employed,
the Content Master Key (CMK) is encrypted with the
intended recipient's key and the resulting encrypted
content is recorded as a byte array, which is referred to
as the JWE Encrypted Key.
Otherwise, when key agreement is employed,
the JWE Encrypted Key is the empty byte array.
</t>
<t hangText="JWE Ciphertext">
A byte array containing the Ciphertext.
</t>
<t hangText="JWE Integrity Value">
A byte array containing a MAC value that ensures the
integrity of the Ciphertext and the parameters used to
create it.
</t>
<t hangText="Encoded JWE Header">
Base64url encoding of the bytes of the
UTF-8 <xref target="RFC3629"/>
representation of the JWE Header.
</t>
<t hangText="Encoded JWE Encrypted Key">
Base64url encoding of the JWE Encrypted Key.
</t>
<t hangText="Encoded JWE Ciphertext">
Base64url encoding of the JWE Ciphertext.
</t>
<t hangText="Encoded JWE Integrity Value">
Base64url encoding of the JWE Integrity Value.
</t>
<t hangText="Header Parameter Name">
The name of a member of the JSON object representing a
JWE Header.
</t>
<t hangText="Header Parameter Value">
The value of a member of the JSON object representing a
JWE Header.
</t>
<t hangText="JWE Compact Serialization">
A representation of the JWE as the concatenation of the
Encoded JWE Header, the Encoded JWE Encrypted Key, the
Encoded JWE Ciphertext, and the Encoded JWE Integrity
Value in that order, with the four strings being separated
by period ('.') characters.
</t>
<t hangText="AEAD Algorithm">
An Authenticated Encryption with Associated Data (AEAD)
<xref target="RFC5116"/> encryption algorithm is one that
provides an integrated content integrity check. AES
Galois/Counter Mode (GCM) is one such algorithm.
</t>
<t hangText="Base64url Encoding">
For the purposes of this specification, this term always
refers to the URL- and filename-safe Base64 encoding
described in <xref target="RFC4648">RFC 4648</xref>,
Section 5, with the (non URL-safe) '=' padding characters
omitted, as permitted by Section 3.2. (See Appendix C of
<xref target="JWS" /> for notes on implementing base64url
encoding without padding.)
</t>
<t hangText="Collision Resistant Namespace">
A namespace that allows names to be allocated in a manner
such that they are highly unlikely to collide with other names.
For instance, collision resistance can be achieved through
administrative delegation of portions of the namespace or
through use of collision-resistant name allocation functions.
Examples of Collision Resistant Namespaces include:
Domain Names,
Object Identifiers (OIDs) as defined in the ITU-T X.660
and X.670 Recommendation series, and
Universally Unique IDentifiers (UUIDs)
<xref target="RFC4122"/>.
When using an administratively delegated namespace,
the definer of a name needs to take
reasonable precautions to ensure they are in control of
the portion of the namespace they use to define the name.
</t>
<t hangText="StringOrURI">
A JSON string value, with the additional requirement that
while arbitrary string values MAY be used, any value
containing a ":" character MUST be a URI
<xref target="RFC3986"/>.
</t>
</list>
</t>
</section>
<section title="JSON Web Encryption (JWE) Overview">
<t>
JWE represents encrypted content using JSON data
structures and base64url encoding. The representation
consists of four parts: the JWE Header, the JWE Encrypted Key,
the JWE Ciphertext, and the JWE Integrity Value.
In the Compact Serialization, the four parts are
base64url-encoded for transmission, and represented
as the concatenation of the encoded strings in that order,
with the four strings being separated by period ('.')
characters.
(A JSON Serialization for this information is defined in the separate
JSON Web Encryption JSON Serialization (JWE-JS) <xref target="JWE-JS" />
specification.)
</t>
<t>
JWE utilizes encryption to ensure the confidentiality
of the Plaintext. JWE adds a content
integrity check if not provided by the underlying encryption
algorithm.
</t>
<section title="Example JWE with an Integrated Integrity Check" anchor="ExampleAEADJWE">
<t>
This example encrypts the plaintext
"Live long and prosper."
to the recipient using RSAES OAEP and AES GCM.
The AES GCM algorithm has an integrated integrity check.
</t>
<t>
The following example JWE Header declares that:
<list style="symbols">
<t>
the Content Master Key is encrypted to the recipient
using the RSAES OAEP algorithm to produce the JWE
Encrypted Key,
</t>
<t>
the Plaintext is encrypted using the AES GCM
algorithm with a 256 bit key to produce the Ciphertext, and
</t>
<t>
the 96 bit Initialization Vector (IV) with the
base64url encoding <spanx
style="verb">48V1_ALb6US04U3b</spanx> was used.
</t>
</list>
</t>
<figure><artwork><![CDATA[{"alg":"RSA-OAEP","enc":"A256GCM","iv":"48V1_ALb6US04U3b"}]]></artwork></figure>
<t>
Base64url encoding the bytes of the UTF-8 representation of
the JWE Header yields this Encoded JWE Header value
(with line breaks for display purposes only):
</t>
<figure><artwork><![CDATA[eyJhbGciOiJSU0EtT0FFUCIsImVuYyI6IkEyNTZHQ00iLCJpdiI6IjQ4VjFfQUxi
NlVTMDRVM2IifQ]]></artwork></figure>
<t>
The remaining steps to finish creating this JWE are:
<list style="symbols">
<t>
Generate a random Content Master Key (CMK)
</t>
<t>
Encrypt the CMK with the recipient's public key using the RSAES OAEP
algorithm to produce the JWE Encrypted Key
</t>
<t>
Base64url encode the JWE Encrypted Key to produce the Encoded JWE Encrypted Key
</t>
<t>
Concatenate the Encoded JWE Header value, a period character ('.'), and the
Encoded JWE Encrypted Key to create the "additional authenticated data" parameter
for the AES GCM algorithm.
</t>
<t>
Encrypt the Plaintext with AES GCM, using the IV,
the CMK as the encryption key, and the "additional authenticated data" value above,
requesting a 128 bit "authentication tag" output
</t>
<t>
Base64url encode the resulting Ciphertext to create the Encoded JWE Ciphertext
</t>
<t>
Base64url encode the resulting "authentication tag" to create the Encoded JWE Integrity Value
</t>
<t>
Assemble the final representation:
The Compact Serialization of this result is the
concatenation of the Encoded JWE Header, the Encoded JWE
Encrypted Key, the Encoded JWE Ciphertext, and the Encoded
JWE Integrity Value in that order, with the four strings
being separated by three period ('.') characters.
</t>
</list>
The final result in this example
(with line breaks for display purposes only) is:
</t>
<figure><artwork><![CDATA[eyJhbGciOiJSU0EtT0FFUCIsImVuYyI6IkEyNTZHQ00iLCJpdiI6IjQ4VjFfQUxi
NlVTMDRVM2IifQ.
jvwoyhWxOMboB5cxX6ncAi7Wp3Q5FKRtlmIx35pfR9HpEa6Oy-iEpxEqM30W3YcR
Q8WU9ouRoO5jd6tfdcpX-2X-OteHw4dnMXdMLjHGGx86LMDeFRAN2KGz7EGPJiva
w0yM80fzT3zY0PKrIvU5ml1M5szqUnX4Jw0-PNcIM_j-L5YkLhv3Yk04XCwTJwxN
NmXCflYAQO9f00Aa213TJJr6dbHV6I642FwU-EWvtEfN3evgX3EFIVYSnT3HCHkA
AIdBQ9ykD-abRzVA_dGp_yJAZQcrZuNTqzThd_22YMPhIpzTygfC_4k7qqxI6t7L
e_l5_o-taUG7vaNAl5FjEQ.
_e21tGGhac_peEFkLXr2dMPUZiUkrw.
YbZSeHCNDZBqAdzpROlyiw]]></artwork></figure>
<t>
See <xref target="OAEPGCMExample"/> for the complete details of computing this JWE.
</t>
</section>
<section title="Example JWE with a Separate Integrity Check" anchor="ExampleNonAEADJWE">
<t>
This example encrypts the plaintext
"Now is the time for all good men to come to the aid of their country."
to the recipient using RSAES-PKCS1-V1_5 and AES CBC.
AES CBC does not have an integrated integrity check,
so a separate integrity check calculation is performed using HMAC SHA-256,
with separate encryption and integrity keys being derived from a master key
using the Concat KDF with the SHA-256 digest function.
</t>
<t>
The following example JWE Header (with line breaks for display purposes only) declares that:
<list style="symbols">
<t>
the Content Master Key is encrypted to the recipient
using the RSAES-PKCS1-V1_5 algorithm to produce the JWE
Encrypted Key,
</t>
<t>
the Plaintext is encrypted using the AES CBC
algorithm with a 128 bit key to produce the Ciphertext,
</t>
<t>
the JWE Integrity Value safeguarding the integrity of the
Ciphertext and the parameters used to create it was
computed with the HMAC SHA-256 algorithm, and
</t>
<t>
the 128 bit Initialization Vector (IV) with the
base64url encoding <spanx
style="verb">AxY8DCtDaGlsbGljb3RoZQ</spanx> was used.
</t>
</list>
</t>
<figure><artwork><![CDATA[{"alg":"RSA1_5","enc":"A128CBC","int":"HS256","iv":"AxY8DCtDaGls
bGljb3RoZQ"}]]></artwork></figure>
<t>
Base64url encoding the bytes of the UTF-8 representation of
the JWE Header yields this Encoded JWE Header value
(with line breaks for display purposes only):
</t>
<figure><artwork><![CDATA[eyJhbGciOiJSU0ExXzUiLCJlbmMiOiJBMTI4Q0JDIiwiaW50IjoiSFMyNTYiLCJp
diI6IkF4WThEQ3REYUdsc2JHbGpiM1JvWlEifQ]]></artwork></figure>
<t>
The remaining steps to finish creating this JWE are like the previous example,
but with an additional step to compute the separate integrity value:
<list style="symbols">
<t>
Generate a random Content Master Key (CMK)
</t>
<t>
Encrypt the CMK with the recipient's public key using the RSAES-PKCS1-V1_5
algorithm to produce the JWE Encrypted Key
</t>
<t>
Base64url encode the JWE Encrypted Key to produce the Encoded JWE Encrypted Key
</t>
<t>
Use the Concat key derivation function
to derive Content Encryption Key (CEK)
and Content Integrity Key (CIK) values from the CMK
</t>
<t>
Encrypt the Plaintext with AES CBC using
the CEK and IV to produce the Ciphertext
</t>
<t>
Base64url encode the resulting Ciphertext to create the Encoded JWE Ciphertext
</t>
<t>
Concatenate the Encoded JWE Header value, a period character ('.'), the
Encoded JWE Encrypted Key, a second period character, and the
Encoded JWE Ciphertext to create the value to integrity protect
</t>
<t>
Compute the HMAC SHA-256 of this value using the CIK to create the JWE Integrity Value
</t>
<t>
Base64url encode the resulting JWE Integrity Value to create the Encoded JWE Integrity Value
</t>
<t>
Assemble the final representation:
The Compact Serialization of this result is the
concatenation of the Encoded JWE Header, the Encoded JWE
Encrypted Key, the Encoded JWE Ciphertext, and the Encoded
JWE Integrity Value in that order, with the four strings
being separated by three period ('.') characters.
</t>
</list>
The final result in this example
(with line breaks for display purposes only) is:
</t>
<figure><artwork><![CDATA[eyJhbGciOiJSU0ExXzUiLCJlbmMiOiJBMTI4Q0JDIiwiaW50IjoiSFMyNTYiLCJp
diI6IkF4WThEQ3REYUdsc2JHbGpiM1JvWlEifQ.
IPI_z172hSWHMFgED8EG9DM6hIXU_6NaO1DImCn0vNeuoBq847Sl6qw_GHSYHJUQ
XtXJq7S_CxWVrI82wjrOyaQca5tLZRZc45BfKHeqByThKI261QevEK56SyAwwXfK
KZjSvkQ5dwTFSgfy76rMSUvVynHYEhdCatBF9HWTAiXPx7hgZixG1FeP_QCmOylz
2VClVyYFCbjKREOwBFf-puNYfO75S3LNlJUtTsGGQL2oTKpMsEiUTdefkje91VX9
h8g7908lFsggbjV7NicJsufuXxnTj1fcWIrRDeNIOmakiPEODi0gTSz0ou-W-LWK
-3T1zYlOIiIKBjsExQKZ-w.
_Z_djlIoC4MDSCKireWS2beti4Q6iSG2UjFujQvdz-_PQdUcFNkOulegD6BgjgdF
LjeB4HHOO7UHvP8PEDu0a0sA2a_-CI0w2YQQ2QQe35M.
c41k4T4eAgCCt63m8ZNmiOinMciFFypOFpvid7i6D0k]]></artwork></figure>
<t>
See <xref target="RSACBCExample"/> for the complete details of computing this JWE.
</t>
</section>
</section>
<section title="JWE Header">
<t>
The members of the JSON object represented by the JWE Header
describe the encryption applied to the Plaintext and optionally
additional properties of the JWE.
The Header Parameter Names within this object MUST be unique;
JWEs with duplicate Header Parameter Names MUST be rejected.
Implementations MUST understand the entire contents of the
header; otherwise, the JWE MUST be rejected.
</t>
<t>
There are two ways of distinguishing whether a header is a
JWS Header or a JWE Header.
The first is by examining the <spanx style="verb">alg</spanx>
(algorithm) header value.
If the value represents a digital signature or MAC algorithm,
or is the value <spanx style="verb">none</spanx>, it is for a JWS;
if it represents an encryption or key agreement algorithm, it is for a JWE.
A second method is determining whether an
<spanx style="verb">enc</spanx> (encryption method) member exists.
If the <spanx style="verb">enc</spanx> member exists, it is a JWE;
otherwise, it is a JWS.
Both methods will yield the same result.
</t>
<t>
There are three classes of Header Parameter Names:
Reserved Header Parameter Names, Public Header Parameter Names,
and Private Header Parameter Names.
</t>
<section title="Reserved Header Parameter Names" anchor="ReservedHeaderParameterName">
<t>
The following header parameter names are reserved
with meanings as defined below. All the
names are short because a core goal of JWE is for the
representations to be compact.
</t>
<t>
Additional reserved header parameter names MAY be defined
via the IANA
JSON Web Signature and Encryption Header Parameters registry
<xref target="JWS" />.
As indicated by the common registry, JWSs and JWEs share a
common header parameter space; when a parameter is used by
both specifications, its usage must be compatible
between the specifications.
</t>
<section title='"alg" (Algorithm) Header Parameter' anchor="algDef">
<t>
The <spanx style="verb">alg</spanx> (algorithm) header
parameter identifies the cryptographic algorithm used to
encrypt or reach agreement upon the Content Master Key (CMK).
The algorithm specified by the <spanx style="verb">alg</spanx> value
MUST be supported by the implementation
and there MUST be a key for use with that algorithm associated with the
intended recipient
or the JWE MUST be rejected.
The <spanx style="verb">alg</spanx> value is case sensitive.
Its value MUST be a string containing a StringOrURI value.
This header parameter is REQUIRED.
</t>
<t>
A list of defined <spanx style="verb">alg</spanx> values for use with
JWE is presented in Section 4.1 of the
JSON Web Algorithms (JWA) <xref target="JWA" /> specification.
<spanx style="verb">alg</spanx> values SHOULD either be
registered in the IANA
JSON Web Signature and Encryption Algorithms registry
<xref target="JWA" /> or be
a URI that contains a Collision Resistant Namespace.
</t>
</section>
<section title='"enc" (Encryption Method) Header Parameter' anchor="encDef">
<t>
The <spanx style="verb">enc</spanx> (encryption method)
header parameter identifies the symmetric
encryption algorithm used to encrypt the Plaintext to produce the Ciphertext.
The algorithm specified by the <spanx style="verb">enc</spanx> value
MUST be supported by the implementation
or the JWE MUST be rejected.
The <spanx style="verb">enc</spanx> value is case sensitive.
Its value MUST be a string containing a StringOrURI value.
This header parameter is REQUIRED.
</t>
<t>
A list of defined <spanx style="verb">enc</spanx> values
is presented in Section 4.2 of the
JSON Web Algorithms (JWA) <xref target="JWA" /> specification.
<spanx style="verb">enc</spanx> values SHOULD either be
registered in the IANA
JSON Web Signature and Encryption Algorithms registry
<xref target="JWA" /> or be
a URI that contains a Collision Resistant Namespace.
</t>
</section>
<section title='"int" (Integrity Algorithm) Header Parameter' anchor="intDef">
<t>
The <spanx style="verb">int</spanx> (integrity algorithm) header
parameter identifies the cryptographic algorithm used to
safeguard the integrity of the Ciphertext and the
parameters used to create it.
The <spanx style="verb">int</spanx> parameter uses the
MAC subset of the algorithm values used by the JWS
<spanx style="verb">alg</spanx> parameter.
The <spanx style="verb">int</spanx> value is case sensitive.
Its value MUST be a string containing a StringOrURI value.
This header parameter is REQUIRED when an AEAD algorithm
is not used to encrypt the Plaintext and MUST NOT be
present when an AEAD algorithm is used.
</t>
<t>
A list of defined <spanx style="verb">int</spanx> values
is presented in Section 4.3 of the
JSON Web Algorithms (JWA) <xref target="JWA" /> specification.
<spanx style="verb">int</spanx> values SHOULD either be
registered in the IANA
JSON Web Signature and Encryption Algorithms registry
<xref target="JWA" /> or be
a URI that contains a Collision Resistant Namespace.
</t>
</section>
<section title='"kdf" (Key Derivation Function) Header Parameter' anchor="kdfDef">
<t>
The <spanx style="verb">kdf</spanx> (key derivation function) header
parameter identifies the cryptographic algorithm used to
derive the CEK and CIK from the CMK.
The <spanx style="verb">kdf</spanx> value is case sensitive.
Its value MUST be a string containing a StringOrURI value.
This header parameter is OPTIONAL when an AEAD algorithm
is not used to encrypt the Plaintext and MUST NOT be
present when an AEAD algorithm is used.
</t>
<t>
When an AEAD algorithm is not used and no <spanx style="verb">kdf</spanx>
header parameter is present, the <spanx style="verb">CS256</spanx> KDF
<xref target="JWA" /> SHALL be used.
</t>
<t>
A list of defined <spanx style="verb">kdf</spanx> values
is presented in Section 4.4 of the
JSON Web Algorithms (JWA) <xref target="JWA" /> specification.
<spanx style="verb">kdf</spanx> values SHOULD either be
registered in the IANA
JSON Web Signature and Encryption Algorithms registry
<xref target="JWA" /> or be
a URI that contains a Collision Resistant Namespace.
</t>
</section>
<section title='"iv" (Initialization Vector) Header Parameter' anchor="ivDef">
<t>
The <spanx style="verb">iv</spanx> (initialization vector)
value for algorithms requiring it, represented as a
base64url encoded string.
This header parameter is OPTIONAL, although its use is
REQUIRED with some <spanx style="verb">enc</spanx> algorithms.
</t>
</section>
<section title='"epk" (Ephemeral Public Key) Header Parameter' anchor="epkDef">
<t>
The <spanx style="verb">epk</spanx> (ephemeral public key)
value created by the originator for the use in key agreement algorithms.
This key is represented as a JSON Web Key <xref target="JWK" /> value.
This header parameter is OPTIONAL, although its use is
REQUIRED with some <spanx style="verb">alg</spanx> algorithms.
</t>
</section>
<section title='"zip" (Compression Algorithm) Header Parameter' anchor="zipDef">
<t>
The <spanx style="verb">zip</spanx> (compression algorithm)
applied to the Plaintext before encryption, if any.
If present, the value of the <spanx style="verb">zip</spanx>
header parameter MUST be the case sensitive string "DEF".
Compression is performed with the
DEFLATE <xref target="RFC1951" /> algorithm.
If no <spanx style="verb">zip</spanx> parameter is present,
no compression is applied to the Plaintext before encryption.
This header parameter is OPTIONAL.
</t>
</section>
<section title='"jku" (JWK Set URL) Header Parameter' anchor="jkuDef">
<t>
The <spanx style="verb">jku</spanx> (JWK Set URL)
header parameter is a URI <xref target="RFC3986"/> that refers to a
resource for a set of JSON-encoded public keys, one of
which corresponds to the key used to
encrypt the JWE; this can be used to determine the private key needed to decrypt the JWE.
The keys MUST be encoded as a JSON Web Key Set (JWK Set) <xref target="JWK" />.
The protocol used to acquire the resource MUST provide
integrity protection; an HTTP GET request to retrieve the
certificate MUST use TLS <xref target="RFC2818"/> <xref target="RFC5246"/>;
the identity of the server MUST be validated, as per
Section 3.1 of HTTP Over TLS <xref target='RFC2818'/>.
This header parameter is OPTIONAL.
</t>
</section>
<section title='"jwk" (JSON Web Key) Header Parameter' anchor="jwkDef">
<t>
The <spanx style="verb">jwk</spanx> (JSON Web Key)
header parameter is a public key that corresponds to the key used to
encrypt the JWE; this can be used to determine the private key needed to decrypt the JWE.
This key is represented as a JSON Web Key <xref target="JWK" />.
This header parameter is OPTIONAL.
</t>
</section>
<section title='"x5u" (X.509 URL) Header Parameter' anchor="x5uDef">
<t>
The <spanx style="verb">x5u</spanx> (X.509 URL) header
parameter is a URI <xref target="RFC3986"/> that refers to a resource for
the X.509 public key certificate or certificate chain <xref target="RFC5280"/>
corresponding to the key used to
encrypt the JWE; this can be used to determine the private key needed to decrypt the JWE.
The identified resource MUST provide a representation of
the certificate or certificate chain that conforms to
<xref target="RFC5280">RFC 5280</xref> in PEM encoded form
<xref target="RFC1421"/>.
The certificate containing the public key of the entity
that encrypted the JWE MUST be the first certificate. This
MAY be followed by additional certificates, with each
subsequent certificate being the one used to certify the
previous one.
The protocol used to acquire the resource MUST provide
integrity protection; an HTTP GET request to retrieve the
certificate MUST use TLS <xref target="RFC2818"/> <xref target="RFC5246"/>;
the identity of the server MUST be validated, as per
Section 3.1 of HTTP Over TLS <xref target='RFC2818'/>.
This header parameter is OPTIONAL.
</t>
</section>
<section title='"x5t" (X.509 Certificate Thumbprint) Header Parameter' anchor="x5tDef">
<t>
The <spanx style="verb">x5t</spanx> (X.509 Certificate Thumbprint)
header parameter provides a base64url encoded
SHA-1 thumbprint (a.k.a. digest) of the DER encoding of
the X.509 certificate <xref target="RFC5280"/> corresponding to the key used to
encrypt the JWE; this can be used to determine the private key needed to decrypt the JWE.
This header parameter is OPTIONAL.
</t>
<t>
If, in the future, certificate thumbprints need to be
computed using hash functions other than SHA-1, it is
suggested that additional related header parameters be
defined for that purpose. For example, it is suggested
that a new <spanx style="verb">x5t#S256</spanx> (X.509
Certificate Thumbprint using SHA-256) header parameter
could be defined by registering it in the IANA
JSON Web Signature and Encryption Header Parameters
registry <xref target="JWS" />.
</t>
</section>
<section title='"x5c" (X.509 Certificate Chain) Header Parameter' anchor="x5cDef">
<t>
The <spanx style="verb">x5c</spanx> (X.509 Certificate Chain)
header parameter contains the X.509 public key
certificate or certificate chain <xref target="RFC5280"/>
corresponding to the key used to
encrypt the JWE; this can be used to determine the private key needed to decrypt the JWE.
The certificate or certificate chain is represented as an
array of certificate values. Each value is a
base64 encoded (<xref target="RFC4648"/> Section 4 - not base64url encoded)
DER <xref target="ITU.X690.1994"/> PKIX certificate value.
The certificate containing the public key of the entity
that encrypted the JWE MUST be the first certificate. This
MAY be followed by additional certificates, with each
subsequent certificate being the one used to certify the
previous one.
The recipient MUST verify the certificate chain according
to <xref target="RFC5280"/> and reject the JWE if any
validation failure occurs.
This header parameter is OPTIONAL.
</t>
<t>
See Appendix B of <xref target="JWS"/> for an example
<spanx style="verb">x5c</spanx> value.
</t>
</section>
<section title='"kid" (Key ID) Header Parameter' anchor="kidDef">
<t>
The <spanx style="verb">kid</spanx> (key ID) header
parameter is a hint indicating which key was used to
encrypt the JWE; this can be used to determine the private key needed to decrypt the JWE.
This parameter allows originators to explicitly signal a change of
key to recipients.
Should the recipient be unable to locate a key
corresponding to the <spanx style="verb">kid</spanx>
value, they SHOULD treat that condition as an error.
The interpretation of the
<spanx style="verb">kid</spanx> value is unspecified.
Its value MUST be a string.
This header parameter is OPTIONAL.
</t>
<t>
When used with a JWK, the <spanx style="verb">kid</spanx>
value MAY be used to match a JWK <spanx style="verb">kid</spanx>
parameter value.
</t>
</section>
<section title='"typ" (Type) Header Parameter' anchor="typDef">
<t>
The <spanx style="verb">typ</spanx> (type) header
parameter is used to declare the type of this object.
The type value <spanx style="verb">JWE</spanx> MAY be used
to indicate that this object is a JWE.
The <spanx style="verb">typ</spanx> value is case sensitive.
Its value MUST be a string.
This header parameter is OPTIONAL.
</t>
<t>
MIME Media Type <xref target="RFC2046"/>
values MAY be used as <spanx style="verb">typ</spanx> values.
</t>
<t>
<spanx style="verb">typ</spanx> values SHOULD either be
registered in the IANA
JSON Web Signature and Encryption Type Values registry
<xref target="JWS" /> or be
a URI that contains a Collision Resistant Namespace.
</t>
</section>
<section title='"cty" (Content Type) Header Parameter' anchor="ctyDef">
<t>
The <spanx style="verb">cty</spanx> (content type) header
parameter is used to declare the type of the encrypted
content (the Plaintext).
The <spanx style="verb">cty</spanx> value is case sensitive.
Its value MUST be a string.
This header parameter is OPTIONAL.
</t>
<t>
The values used for the <spanx style="verb">cty</spanx>
header parameter come from the same value space as the
<spanx style="verb">typ</spanx> header parameter,
with the same rules applying.
</t>
</section>
</section>
<section title="Public Header Parameter Names" anchor="PublicHeaderParameterName">
<t>
Additional header parameter names can be defined by those
using JWEs. However, in order to prevent collisions, any new
header parameter name SHOULD either be registered in the IANA
JSON Web Signature and Encryption Header Parameters registry
<xref target="JWS" /> or be
a URI that contains a Collision Resistant Namespace.
In each case, the definer of the name
or value needs to take reasonable precautions to make sure they
are in control of the part of the namespace they use to
define the header parameter name.
</t>
<t>
New header parameters should be introduced sparingly, as
they can result in non-interoperable JWEs.
</t>
</section>
<section title="Private Header Parameter Names" anchor="PrivateHeaderParameterName">
<t>
A producer and consumer of a JWE may agree to any header
parameter name that is not a Reserved Name <xref
target="ReservedHeaderParameterName"></xref> or a Public
Name <xref
target="PublicHeaderParameterName"></xref>. Unlike Public
Names, these private names are subject to collision and
should be used with caution.
</t>
</section>
</section>
<section anchor="sec.encryption" title="Message Encryption">
<t>
The message encryption process is as follows. The order of
the steps is not significant in cases where there are no
dependencies between the inputs and outputs of the steps.
</t>
<t><list style="numbers">
<t>
When key wrapping or key encryption are employed,
generate a random Content Master Key (CMK).
See <xref target="RFC4086">RFC 4086</xref> for
considerations on generating random values.
Otherwise, when key agreement is employed, use the
key agreement algorithm to compute the value of the
Content Master Key (CMK).
The CMK MUST have a length equal to that of the
larger of the required encryption and integrity keys.
</t>
<t>
When key wrapping or key encryption are employed,
encrypt the CMK for the recipient (see <xref
target="sec.encrypt_cmk"/>) and let the result be the
JWE Encrypted Key.
Otherwise, when key agreement is employed, let the
JWE Encrypted Key be an empty byte array.
</t>
<t>
Base64url encode the JWE Encrypted Key to create the
Encoded JWE Encrypted Key.
</t>
<t>
Generate a random Initialization Vector (IV) of the
correct size for the algorithm (if required for the
algorithm).
</t>
<t>
If not using an AEAD algorithm, run the key derivation
algorithm specified by the <spanx style="verb">kdf</spanx> header parameter to
generate the Content Encryption Key (CEK) and the Content
Integrity Key (CIK); otherwise (when using an AEAD
algorithm), set the CEK to be the CMK.
</t>
<t>
Compress the Plaintext if a <spanx
style="verb">zip</spanx> parameter was included.
</t>
<t>
Serialize the (compressed) Plaintext into a byte sequence M.
</t>
<t>
Create a JWE Header containing the encryption
parameters used.
Note that white space is explicitly allowed
in the representation and no canonicalization need be performed
before encoding.
</t>
<t>
Base64url encode the bytes of the UTF-8 representation of
the JWE Header to create the Encoded JWE Header.
</t>
<t>
Encrypt M using the CEK and IV to form the byte sequence C.
If an AEAD algorithm is used, use the bytes of the ASCII
representation of the concatenation of the
Encoded JWE Header, a period ('.') character, and the
Encoded JWE Encrypted Key as the "additional authenticated data"
parameter value for the encryption.
</t>
<t>
Base64url encode C to create the Encoded JWE Ciphertext.
</t>
<t>
If not using an AEAD algorithm, run the integrity
algorithm (see <xref target="sec.integrity"/>) using the
CIK to compute the JWE Integrity Value; otherwise (when
using an AEAD algorithm), set the JWE Integrity Value to
be the "authentication tag" value produced by the AEAD algorithm.
</t>
<t>
Base64url encode the JWE Integrity Value to create the
Encoded JWE Integrity Value.
</t>
<t>
The four encoded parts, taken together, are the result.
</t>
<t>
The Compact Serialization of this result is the
concatenation of the Encoded JWE Header, the Encoded JWE
Encrypted Key, the Encoded JWE Ciphertext, and the Encoded
JWE Integrity Value in that order, with the four strings
being separated by period ('.') characters.
</t>
</list></t>
</section>
<section anchor="sec.decryption" title="Message Decryption">
<t>
The message decryption process is the reverse of the
encryption process. The order of the steps is not significant
in cases where there are no dependencies between the inputs
and outputs of the steps. If any of these steps fails, the
JWE MUST be rejected.
</t>
<t>
<list style="numbers">
<t>
Determine the Encoded JWE Header, the Encoded
JWE Encrypted Key, the Encoded JWE Ciphertext, and the
Encoded JWE Integrity Value values contained in the JWE.
When using the Compact Serialization, these four values are
represented in that order, separated by period characters.
</t>
<t>
The Encoded JWE Header, the Encoded JWE Encrypted Key, the
Encoded JWE Ciphertext, and the Encoded JWE Integrity
Value MUST be successfully base64url decoded following the
restriction that no padding characters have been used.
</t>
<t>
The resulting JWE Header MUST be completely valid
JSON syntax conforming to <xref target="RFC4627">RFC 4627</xref>.
</t>
<t>
The resulting JWE Header MUST be validated to only include
parameters and values whose syntax and semantics are both
understood and supported.
</t>
<t>
Verify that the JWE Header references a key known to the
recipient.
</t>
<t>
When key wrapping or key encryption are employed,
decrypt the JWE Encrypted Key to produce the Content
Master Key (CMK).
Otherwise, when key agreement is employed, use the
key agreement algorithm to compute the value of the
Content Master Key (CMK).
The CMK MUST have a length equal to that of the
larger of the required encryption and integrity keys.
</t>
<t>
If not using an AEAD algorithm, run the key derivation
algorithm specified by the <spanx style="verb">kdf</spanx> header parameter to
generate the Content Encryption Key (CEK) and the Content
Integrity Key (CIK); otherwise (when using an AEAD
algorithm), set the CEK to be the CMK.
</t>
<t>
Decrypt the binary representation of the JWE Ciphertext
using the CEK and IV.
If an AEAD algorithm is used, use the bytes of the ASCII
representation of the concatenation of the
Encoded JWE Header, a period ('.') character, and the
Encoded JWE Encrypted Key as the "additional authenticated data"
parameter value for the decryption.
</t>
<t>
If not using an AEAD algorithm, run the integrity
algorithm (see <xref target="sec.integrity"/>) using the
CIK to compute an integrity value for the input received.
This computed value MUST match the received JWE
Integrity Value; otherwise (when using an AEAD algorithm),
the received JWE Integrity Value MUST match the
"authentication tag" value produced by the AEAD algorithm.
</t>
<t>
Uncompress the result of the previous step, if a <spanx
style="verb">zip</spanx> parameter was included.
</t>
<t>
Output the resulting Plaintext.
</t>
</list>
</t>
</section>
<section anchor="sec.encrypt_cmk" title="CMK Encryption">
<t>
JWE supports two forms of Content Master Key (CMK) encryption:
<list style="symbols">
<t>
Asymmetric encryption under the recipient's public key.
</t>
<t>
Symmetric encryption under a key shared between the sender and receiver.
</t>
</list>
See the algorithms registered for <spanx style="verb">enc</spanx> usage in the IANA
JSON Web Signature and Encryption Algorithms registry <xref target="JWA" />
and Section 4.1 of the
JSON Web Algorithms (JWA) <xref target="JWA" /> specification
for lists of encryption algorithms that can be used for CMK encryption.
</t>
</section>
<section anchor="sec.integrity" title="Integrity Value Calculation">
<t>
When a non-AEAD algorithm is used (an algorithm without an
integrated content check), JWE adds an explicit integrity
check value to the representation. This value is computed in
the manner described in the JSON Web Signature (JWS) <xref
target="JWS" /> specification, with these modifications:
<list style="symbols">
<t>
The algorithm used is taken from the <spanx
style="verb">int</spanx> (integrity algorithm) header
parameter rather than the <spanx style="verb">alg</spanx>
header parameter.
</t>
<t>
The algorithm MUST be a MAC algorithm (such as HMAC SHA-256).
</t>
<t>
The JWS Secured Input used is the bytes of the ASCII
representation of the concatenation of the
Encoded JWE Header, a period ('.') character, the Encoded
JWE Encrypted Key, a period ('.') character, and the
Encoded JWE Ciphertext.
</t>
<t>
The CIK is used as the MAC key.
</t>
</list>
The computed JWS Signature value is the resulting integrity value.
</t>
</section>
<section title="Encrypting JWEs with Cryptographic Algorithms" anchor="Encrypting">
<t>
JWE uses cryptographic algorithms to encrypt the Plaintext
and the Content Encryption Key (CMK) and to provide integrity
protection for the JWE Header, JWE Encrypted Key, and JWE Ciphertext.
The JSON Web Algorithms (JWA) <xref target="JWA" />
specification specifies a set of cryptographic algorithms and
identifiers to be used with this specification
and defines registries for additional such algorithms.
Specifically, Section 4.1 specifies a set of
<spanx style="verb">alg</spanx> (algorithm) header parameter values,
Section 4.2 specifies a set of
<spanx style="verb">enc</spanx> (encryption method) header parameter values,
Section 4.3 specifies a set of
<spanx style="verb">int</spanx> (integrity algorithm) header parameter values,
and Section 4.4 specifies a set of
<spanx style="verb">kdf</spanx> (key derivation function) header parameter values
intended for use this specification.
It also describes the semantics and operations that are
specific to these algorithms and algorithm families.
</t>
<t>
Public keys employed for encryption can be identified using the
Header Parameter methods described in <xref
target="ReservedHeaderParameterName" /> or can be distributed
using methods that are outside the scope of this
specification.
</t>
</section>
<section title="IANA Considerations" anchor="IANA">
<section title="Registration of JWE Header Parameter Names" anchor="HeaderParamReg">
<t>
This specification registers the Header Parameter Names defined in
<xref target="ReservedHeaderParameterName"/> in the IANA
JSON Web Signature and Encryption Header Parameters registry
<xref target="JWS" />.
</t>
<section title='Registry Contents'>
<t>
<list style='symbols'>
<t>
Header Parameter Name: <spanx style="verb">alg</spanx>
</t>
<t>
Change Controller: IETF
</t>
<t>
Specification Document(s): <xref target="algDef"/> of [[ this document ]]
</t>
</list>
<list style='symbols'>
<t>
Header Parameter Name: <spanx style="verb">enc</spanx>
</t>
<t>
Change Controller: IETF
</t>
<t>
Specification Document(s): <xref target="encDef"/> of [[ this document ]]
</t>
</list>
<list style='symbols'>
<t>
Header Parameter Name: <spanx style="verb">int</spanx>
</t>
<t>
Change Controller: IETF
</t>
<t>
Specification Document(s): <xref target="intDef"/> of [[ this document ]]
</t>
</list>
<list style='symbols'>
<t>
Header Parameter Name: <spanx style="verb">kdf</spanx>
</t>
<t>
Change Controller: IETF
</t>
<t>
Specification Document(s): <xref target="kdfDef"/> of [[ this document ]]
</t>
</list>
<list style='symbols'>
<t>
Header Parameter Name: <spanx style="verb">iv</spanx>
</t>
<t>
Change Controller: IETF
</t>
<t>
Specification Document(s): <xref target="ivDef"/> of [[ this document ]]
</t>
</list>
<list style='symbols'>
<t>
Header Parameter Name: <spanx style="verb">epk</spanx>
</t>
<t>
Change Controller: IETF
</t>
<t>
Specification Document(s): <xref target="epkDef"/> of [[ this document ]]
</t>
</list>
<list style='symbols'>
<t>
Header Parameter Name: <spanx style="verb">zip</spanx>
</t>
<t>
Change Controller: IETF
</t>
<t>
Specification Document(s): <xref target="zipDef"/> of [[ this document ]]
</t>
</list>
<list style='symbols'>
<t>
Header Parameter Name: <spanx style="verb">jku</spanx>
</t>
<t>
Change Controller: IETF
</t>
<t>
Specification Document(s): <xref target="jkuDef"/> of [[ this document ]]
</t>
</list>
<list style='symbols'>
<t>
Header Parameter Name: <spanx style="verb">jwk</spanx>
</t>
<t>
Change Controller: IETF
</t>
<t>
Specification document(s): <xref target="jwkDef"/> of [[ this document ]]
</t>
</list>
<list style='symbols'>
<t>
Header Parameter Name: <spanx style="verb">x5u</spanx>
</t>
<t>
Change Controller: IETF
</t>
<t>
Specification Document(s): <xref target="x5uDef"/> of [[ this document ]]
</t>
</list>
<list style='symbols'>
<t>
Header Parameter Name: <spanx style="verb">x5t</spanx>
</t>
<t>
Change Controller: IETF
</t>
<t>
Specification Document(s): <xref target="x5tDef"/> of [[ this document ]]
</t>
</list>
<list style='symbols'>
<t>
Header Parameter Name: <spanx style="verb">x5c</spanx>
</t>
<t>
Change Controller: IETF
</t>
<t>
Specification Document(s): <xref target="x5cDef"/> of [[ this document ]]
</t>
</list>
<list style='symbols'>
<t>
Header Parameter Name: <spanx style="verb">kid</spanx>
</t>
<t>
Change Controller: IETF
</t>
<t>
Specification Document(s): <xref target="kidDef"/> of [[ this document ]]
</t>
</list>
<list style='symbols'>
<t>
Header Parameter Name: <spanx style="verb">typ</spanx>
</t>
<t>
Change Controller: IETF
</t>
<t>
Specification Document(s): <xref target="typDef"/> of [[ this document ]]
</t>
</list>
<list style='symbols'>
<t>
Header Parameter Name: <spanx style="verb">cty</spanx>
</t>
<t>
Change Controller: IETF
</t>
<t>
Specification Document(s): <xref target="ctyDef"/> of [[ this document ]]
</t>
</list>
</t>
</section>
</section>
<section title='JSON Web Signature and Encryption Type Values Registration'>
<section title='Registry Contents'>
<t>
This specification registers the <spanx style='verb'>JWE</spanx>
type value in the
IANA JSON Web Signature and Encryption Type Values registry <xref target="JWS"/>:
<list style='symbols'>
<t>
"typ" Header Parameter Value: <spanx style='verb'>JWE</spanx>
</t>
<t>
Abbreviation for MIME Type: application/jwe
</t>
<t>
Change Controller: IETF
</t>
<t>
Specification Document(s): <xref target="typDef"/> of [[ this document ]]
</t>
</list>
</t>
</section>
</section>
<section title="Media Type Registration">
<section title='Registry Contents'>
<t>
This specification registers the <spanx
style="verb">application/jwe</spanx> Media Type <xref target="RFC2046"/>
in the MIME Media Type registry <xref target="RFC4288"/>
to indicate that the content is a JWE using the Compact Serialization.
<list style="symbols">
<t>
Type Name: application
</t>
<t>
Subtype Name: jwe
</t>
<t>
Required Parameters: n/a
</t>
<t>
Optional Parameters: n/a
</t>
<t>
Encoding considerations: JWE values are encoded as a
series of base64url encoded values (some of which may be the
empty string) separated by period ('.') characters
</t>
<t>
Security Considerations: See the Security Considerations section of this document
</t>
<t>
Interoperability Considerations: n/a
</t>
<t>
Published Specification: [[ this document ]]
</t>
<t>
Applications that use this media type:
OpenID Connect and other applications using encrypted JWTs
</t>
<t>
Additional Information: Magic number(s): n/a,
File extension(s): n/a,
Macintosh file type code(s): n/a
</t>
<t>
Person & email address to contact for further information: Michael B. Jones, mbj@microsoft.com
</t>
<t>
Intended Usage: COMMON
</t>
<t>
Restrictions on Usage: none
</t>
<t>
Author: Michael B. Jones, mbj@microsoft.com
</t>
<t>
Change Controller: IETF
</t>
</list>
</t>
</section>
</section>
</section>
<section title="Security Considerations" anchor="Security">
<t>
All of the security issues faced by any cryptographic application
must be faced by a JWS/JWE/JWK agent. Among these issues are protecting
the user's private key, preventing various attacks, and helping the
user avoid mistakes such as inadvertently encrypting a message for
the wrong recipient. The entire list of security considerations is
beyond the scope of this document, but some significant concerns are
listed here.
</t>
<t>
All the security considerations in the JWS specification
also apply to this specification.
Likewise, all the security considerations in
<xref target="W3C.CR-xmlenc-core1-20120313">XML Encryption 1.1</xref>
also apply to JWE, other than those that are XML specific.
</t>
</section>
<section title="Open Issues" anchor="TBD">
<t>
[[ to be removed by the RFC editor before publication as an RFC ]]
</t>
<t>
The following items remain to be considered or done in this draft:
<list style="symbols">
<t>
Should we define an optional nonce and/or timestamp header parameter?
(Use of a nonce is an effective countermeasure to some kinds of attacks.)
</t>
<t>
When doing key agreement, do we want to also use a separate CMK and
encrypt the CMK with the agreed upon key or just use the
agreed upon key directly as the CMK? Having a
CMK would have value in the multiple recipients case, as
it would allow multiple recipients to share the same
ciphertext even when key agreement is used, but it seems that
it's just extra overhead in the single recipient case.
</t>
<t>
Do we want to consolidate the combination of the
<spanx style="verb">enc</spanx>, <spanx style="verb">int</spanx>,
and <spanx style="verb">kdf</spanx> parameters into a single new
<spanx style="verb">enc</spanx> parameter defining composite AEAD algorithms?
For instance, we might define a composite algorithm A128CBC with HS256 and CS256
and another composite algorithm A256CBC with HS512 and CS512.
A symmetry argument for doing this is that the <spanx style="verb">int</spanx>
and <spanx style="verb">kdf</spanx> parameters are not used with AEAD algorithms.
An argument against it is that in some cases, integrity is not needed because it's
provided by other means, and so having the flexibility to not use an
<spanx style="verb">int</spanx> algorithm or key derivation
with a non-AEAD <spanx style="verb">enc</spanx> algorithm could be useful.
</t>
</list>
</t>
</section>
</middle>
<back>
<references title="Normative References">
<?rfc include='http://xml.resource.org/public/rfc/bibxml/reference.RFC.1421.xml' ?>
<?rfc include='http://xml.resource.org/public/rfc/bibxml/reference.RFC.1951.xml' ?>
<?rfc include='http://xml.resource.org/public/rfc/bibxml/reference.RFC.2046.xml' ?>
<?rfc include='http://xml.resource.org/public/rfc/bibxml/reference.RFC.2119.xml' ?>
<?rfc include='http://xml.resource.org/public/rfc/bibxml/reference.RFC.2818.xml' ?>
<?rfc include='http://xml.resource.org/public/rfc/bibxml/reference.RFC.3629.xml' ?>
<?rfc include='http://xml.resource.org/public/rfc/bibxml/reference.RFC.3986.xml' ?>
<?rfc include='http://xml.resource.org/public/rfc/bibxml/reference.RFC.4086.xml' ?>
<?rfc include='http://xml.resource.org/public/rfc/bibxml/reference.RFC.4288.xml' ?>
<?rfc include='http://xml.resource.org/public/rfc/bibxml/reference.RFC.4627.xml' ?>
<?rfc include='http://xml.resource.org/public/rfc/bibxml/reference.RFC.4648.xml' ?>
<?rfc include='http://xml.resource.org/public/rfc/bibxml/reference.RFC.5116.xml' ?>
<?rfc include='http://xml.resource.org/public/rfc/bibxml/reference.RFC.5246.xml' ?>
<?rfc include='http://xml.resource.org/public/rfc/bibxml/reference.RFC.5280.xml' ?>
<?rfc include='http://xml.resource.org/public/rfc/bibxml2/_reference.ITU.X690.1994.xml' ?>
<reference anchor="JWS">
<front>
<title>JSON Web Signature (JWS)</title>
<author fullname="Michael B. Jones" initials="M.B." surname="Jones">
<organization>Microsoft</organization>
<address>
<email>mbj@microsoft.com</email>
<uri>http://self-issued.info/</uri>
</address>
</author>
<author fullname="John Bradley" initials="J." surname="Bradley">
<organization abbrev="Ping Identity">Ping Identity</organization>
<address>
<email>ve7jtb@ve7jtb.com</email>
</address>
</author>
<author fullname="Nat Sakimura" initials="N." surname="Sakimura">
<organization abbrev="NRI">Nomura Research Institute</organization>
<address>
<email>n-sakimura@nri.co.jp</email>
</address>
</author>
<date day="6" month="July" year="2012" />
</front>
<format target="http://tools.ietf.org/html/draft-ietf-jose-json-web-signature" type="HTML" />
</reference>
<reference anchor="JWK">
<front>
<title>JSON Web Key (JWK)</title>
<author fullname="Michael B. Jones" initials="M.B." surname="Jones">
<organization>Microsoft</organization>
<address>
<email>mbj@microsoft.com</email>
<uri>http://self-issued.info/</uri>
</address>
</author>
<date day="6" month="July" year="2012" />
</front>
<format target="http://tools.ietf.org/html/draft-ietf-jose-json-web-key" type="HTML" />
</reference>
<reference anchor="JWA">
<front>
<title>JSON Web Algorithms (JWA)</title>
<author fullname="Michael B. Jones" initials="M.B." surname="Jones">
<organization>Microsoft</organization>
<address>
<email>mbj@microsoft.com</email>
<uri>http://self-issued.info/</uri>
</address>
</author>
<date day="6" month="July" year="2012" />
</front>
<format target="http://tools.ietf.org/html/draft-ietf-jose-json-web-algorithms" type="HTML" />
</reference>
</references>
<references title="Informative References">
<?rfc include='http://xml.resource.org/public/rfc/bibxml/reference.RFC.4122.xml' ?>
<?rfc include='http://xml.resource.org/public/rfc/bibxml/reference.RFC.5652.xml' ?>
<?rfc include="http://xml.resource.org/public/rfc/bibxml4/reference.W3C.CR-xmlenc-core1-20120313.xml" ?>
<?rfc include="http://xml.resource.org/public/rfc/bibxml3/reference.I-D.draft-rescorla-jsms-00.xml" ?>
<reference anchor="JWE-JS">
<front>
<title abbrev="JWE JSON Serialization (JWE-JS)">JSON Web Encryption JSON Serialization (JWE-JS)</title>
<author fullname="Michael B. Jones" initials="M.B." surname="Jones">
<organization>Microsoft</organization>
<address>
<email>mbj@microsoft.com</email>
<uri>http://self-issued.info/</uri>
</address>
</author>
<date day="6" month="July" year="2012" />
</front>
<format target="http://tools.ietf.org/html/draft-jones-json-web-encryption-json-serialization" type="HTML" />
</reference>
<reference anchor="JSE">
<front>
<title>JSON Simple Encryption</title>
<author fullname="John Bradley" initials="J." surname="Bradley">
<organization>independent</organization>
</author>
<author fullname="Nat Sakimura (editor)" initials="N. " surname="Sakimura (editor)">
<organization abbrev="NRI">Nomura Research Institute</organization>
</author>
<date month="September" year="2010" />
</front>
<format target="http://jsonenc.info/enc/1.0/" type="HTML" />
</reference>
</references>
<section title="JWE Examples" anchor="JWEExamples">
<t>
This section provides examples of JWE computations.
</t>
<section title="Example JWE using RSAES OAEP and AES GCM" anchor="OAEPGCMExample">
<t>
This example encrypts the plaintext
"Live long and prosper."
to the recipient using RSAES OAEP and AES GCM.
The AES GCM algorithm has an integrated integrity check.
The representation of this plaintext is:
</t>
<t>
[76, 105, 118, 101, 32, 108, 111, 110, 103, 32, 97, 110, 100, 32, 112, 114,
111, 115, 112, 101, 114, 46]
</t>
<section title="JWE Header">
<t>
The following example JWE Header declares that:
<list style="symbols">
<t>
the Content Master Key is encrypted to the recipient
using the RSAES OAEP algorithm to produce the JWE
Encrypted Key,
</t>
<t>
the Plaintext is encrypted using the AES GCM
algorithm with a 256 bit key to produce the Ciphertext, and
</t>
<t>
the 96 bit Initialization Vector (IV)
[227, 197, 117, 252, 2, 219, 233, 68, 180, 225, 77, 219]
with the base64url encoding <spanx
style="verb">48V1_ALb6US04U3b</spanx> was used.
</t>
</list>
</t>
<figure><artwork><![CDATA[{"alg":"RSA-OAEP","enc":"A256GCM","iv":"48V1_ALb6US04U3b"}]]></artwork></figure>
</section>
<section title="Encoded JWE Header">
<t>
Base64url encoding the bytes of the UTF-8 representation of
the JWE Header yields this Encoded JWE Header value
(with line breaks for display purposes only):
</t>
<figure><artwork><![CDATA[eyJhbGciOiJSU0EtT0FFUCIsImVuYyI6IkEyNTZHQ00iLCJpdiI6IjQ4VjFfQUxi
NlVTMDRVM2IifQ]]></artwork></figure>
</section>
<section title="Content Master Key (CMK)">
<t>
Generate a random Content Master Key (CMK). In this example, the key value is:
</t>
<t>
[177, 161, 244, 128, 84, 143, 225, 115, 63, 180, 3, 255, 107, 154, 212, 246,
138, 7, 110, 91, 112, 46, 34, 105, 47, 130, 203, 46, 122, 234, 64, 252]
</t>
</section>
<section title="Key Encryption">
<t>
Encrypt the CMK with the recipient's public key using the RSAES OAEP
algorithm to produce the JWE Encrypted Key.
In this example, the RSA key parameters are:
</t>
<texttable>
<ttcol align="left">Parameter Name</ttcol>
<ttcol align="left">Value</ttcol>
<c>Modulus</c>
<c>
[161, 168, 84, 34, 133, 176, 208, 173, 46, 176, 163, 110, 57, 30, 135, 227,
9, 31, 226, 128, 84, 92, 116, 241, 70, 248, 27, 227, 193, 62, 5, 91,
241, 145, 224, 205, 141, 176, 184, 133, 239, 43, 81, 103, 9, 161, 153, 157,
179, 104, 123, 51, 189, 34, 152, 69, 97, 69, 78, 93, 140, 131, 87, 182,
169, 101, 92, 142, 3, 22, 167, 8, 212, 56, 35, 79, 210, 222, 192, 208,
252, 49, 109, 138, 173, 253, 210, 166, 201, 63, 102, 74, 5, 158, 41, 90,
144, 108, 160, 79, 10, 89, 222, 231, 172, 31, 227, 197, 0, 19, 72, 81,
138, 78, 136, 221, 121, 118, 196, 17, 146, 10, 244, 188, 72, 113, 55, 221,
162, 217, 171, 27, 57, 233, 210, 101, 236, 154, 199, 56, 138, 239, 101, 48,
198, 186, 202, 160, 76, 111, 234, 71, 57, 183, 5, 211, 171, 136, 126, 64,
40, 75, 58, 89, 244, 254, 107, 84, 103, 7, 236, 69, 163, 18, 180, 251,
58, 153, 46, 151, 174, 12, 103, 197, 181, 161, 162, 55, 250, 235, 123, 110,
17, 11, 158, 24, 47, 133, 8, 199, 235, 107, 126, 130, 246, 73, 195, 20,
108, 202, 176, 214, 187, 45, 146, 182, 118, 54, 32, 200, 61, 201, 71, 243,
1, 255, 131, 84, 37, 111, 211, 168, 228, 45, 192, 118, 27, 197, 235, 232,
36, 10, 230, 248, 190, 82, 182, 140, 35, 204, 108, 190, 253, 186, 186, 27]
</c>
<c>Exponent</c>
<c>
[1, 0, 1]
</c>
<c>Private Exponent</c>
<c>
[144, 183, 109, 34, 62, 134, 108, 57, 44, 252, 10, 66, 73, 54, 16, 181,
233, 92, 54, 219, 101, 42, 35, 178, 63, 51, 43, 92, 119, 136, 251, 41,
53, 23, 191, 164, 164, 60, 88, 227, 229, 152, 228, 213, 149, 228, 169, 237,
104, 71, 151, 75, 88, 252, 216, 77, 251, 231, 28, 97, 88, 193, 215, 202,
248, 216, 121, 195, 211, 245, 250, 112, 71, 243, 61, 129, 95, 39, 244, 122,
225, 217, 169, 211, 165, 48, 253, 220, 59, 122, 219, 42, 86, 223, 32, 236,
39, 48, 103, 78, 122, 216, 187, 88, 176, 89, 24, 1, 42, 177, 24, 99,
142, 170, 1, 146, 43, 3, 108, 64, 194, 121, 182, 95, 187, 134, 71, 88,
96, 134, 74, 131, 167, 69, 106, 143, 121, 27, 72, 44, 245, 95, 39, 194,
179, 175, 203, 122, 16, 112, 183, 17, 200, 202, 31, 17, 138, 156, 184, 210,
157, 184, 154, 131, 128, 110, 12, 85, 195, 122, 241, 79, 251, 229, 183, 117,
21, 123, 133, 142, 220, 153, 9, 59, 57, 105, 81, 255, 138, 77, 82, 54,
62, 216, 38, 249, 208, 17, 197, 49, 45, 19, 232, 157, 251, 131, 137, 175,
72, 126, 43, 229, 69, 179, 117, 82, 157, 213, 83, 35, 57, 210, 197, 252,
171, 143, 194, 11, 47, 163, 6, 253, 75, 252, 96, 11, 187, 84, 130, 210,
7, 121, 78, 91, 79, 57, 251, 138, 132, 220, 60, 224, 173, 56, 224, 201]
</c>
</texttable>
<t>
The resulting JWE Encrypted Key value is:
</t>
<t>
[142, 252, 40, 202, 21, 177, 56, 198, 232, 7, 151, 49, 95, 169, 220, 2,
46, 214, 167, 116, 57, 20, 164, 109, 150, 98, 49, 223, 154, 95, 71, 209,
233, 17, 174, 142, 203, 232, 132, 167, 17, 42, 51, 125, 22, 221, 135, 17,
67, 197, 148, 246, 139, 145, 160, 238, 99, 119, 171, 95, 117, 202, 87, 251,
101, 254, 58, 215, 135, 195, 135, 103, 49, 119, 76, 46, 49, 198, 27, 31,
58, 44, 192, 222, 21, 16, 13, 216, 161, 179, 236, 65, 143, 38, 43, 218,
195, 76, 140, 243, 71, 243, 79, 124, 216, 208, 242, 171, 34, 245, 57, 154,
93, 76, 230, 204, 234, 82, 117, 248, 39, 13, 62, 60, 215, 8, 51, 248,
254, 47, 150, 36, 46, 27, 247, 98, 77, 56, 92, 44, 19, 39, 12, 77,
54, 101, 194, 126, 86, 0, 64, 239, 95, 211, 64, 26, 219, 93, 211, 36,
154, 250, 117, 177, 213, 232, 142, 184, 216, 92, 20, 248, 69, 175, 180, 71,
205, 221, 235, 224, 95, 113, 5, 33, 86, 18, 157, 61, 199, 8, 121, 0,
0, 135, 65, 67, 220, 164, 15, 230, 155, 71, 53, 64, 253, 209, 169, 255,
34, 64, 101, 7, 43, 102, 227, 83, 171, 52, 225, 119, 253, 182, 96, 195,
225, 34, 156, 211, 202, 7, 194, 255, 137, 59, 170, 172, 72, 234, 222, 203,
123, 249, 121, 254, 143, 173, 105, 65, 187, 189, 163, 64, 151, 145, 99, 17]
</t>
</section>
<section title="Encoded JWE Encrypted Key">
<t>
Base64url encode the JWE Encrypted Key to produce the Encoded JWE Encrypted Key.
This result (with line breaks for display purposes only) is:
</t>
<figure><artwork><![CDATA[jvwoyhWxOMboB5cxX6ncAi7Wp3Q5FKRtlmIx35pfR9HpEa6Oy-iEpxEqM30W3YcR
Q8WU9ouRoO5jd6tfdcpX-2X-OteHw4dnMXdMLjHGGx86LMDeFRAN2KGz7EGPJiva
w0yM80fzT3zY0PKrIvU5ml1M5szqUnX4Jw0-PNcIM_j-L5YkLhv3Yk04XCwTJwxN
NmXCflYAQO9f00Aa213TJJr6dbHV6I642FwU-EWvtEfN3evgX3EFIVYSnT3HCHkA
AIdBQ9ykD-abRzVA_dGp_yJAZQcrZuNTqzThd_22YMPhIpzTygfC_4k7qqxI6t7L
e_l5_o-taUG7vaNAl5FjEQ]]></artwork></figure>
</section>
<section title='"Additional Authenticated Data" Parameter'>
<t>
Concatenate the Encoded JWE Header value, a period character ('.'), and the
Encoded JWE Encrypted Key to create the "additional authenticated data" parameter
for the AES GCM algorithm.
This result (with line breaks for display purposes only) is:
</t>
<figure><artwork><![CDATA[eyJhbGciOiJSU0EtT0FFUCIsImVuYyI6IkEyNTZHQ00iLCJpdiI6IjQ4VjFfQUxi
NlVTMDRVM2IifQ.
jvwoyhWxOMboB5cxX6ncAi7Wp3Q5FKRtlmIx35pfR9HpEa6Oy-iEpxEqM30W3YcR
Q8WU9ouRoO5jd6tfdcpX-2X-OteHw4dnMXdMLjHGGx86LMDeFRAN2KGz7EGPJiva
w0yM80fzT3zY0PKrIvU5ml1M5szqUnX4Jw0-PNcIM_j-L5YkLhv3Yk04XCwTJwxN
NmXCflYAQO9f00Aa213TJJr6dbHV6I642FwU-EWvtEfN3evgX3EFIVYSnT3HCHkA
AIdBQ9ykD-abRzVA_dGp_yJAZQcrZuNTqzThd_22YMPhIpzTygfC_4k7qqxI6t7L
e_l5_o-taUG7vaNAl5FjEQ]]></artwork></figure>
<t>
The representation of this value is:
</t>
<t>
[101, 121, 74, 104, 98, 71, 99, 105, 79, 105, 74, 83, 85, 48, 69, 116,
84, 48, 70, 70, 85, 67, 73, 115, 73, 109, 86, 117, 89, 121, 73, 54,
73, 107, 69, 121, 78, 84, 90, 72, 81, 48, 48, 105, 76, 67, 74, 112,
100, 105, 73, 54, 73, 106, 81, 52, 86, 106, 70, 102, 81, 85, 120, 105,
78, 108, 86, 84, 77, 68, 82, 86, 77, 50, 73, 105, 102, 81, 46, 106,
118, 119, 111, 121, 104, 87, 120, 79, 77, 98, 111, 66, 53, 99, 120, 88,
54, 110, 99, 65, 105, 55, 87, 112, 51, 81, 53, 70, 75, 82, 116, 108,
109, 73, 120, 51, 53, 112, 102, 82, 57, 72, 112, 69, 97, 54, 79, 121,
45, 105, 69, 112, 120, 69, 113, 77, 51, 48, 87, 51, 89, 99, 82, 81,
56, 87, 85, 57, 111, 117, 82, 111, 79, 53, 106, 100, 54, 116, 102, 100,
99, 112, 88, 45, 50, 88, 45, 79, 116, 101, 72, 119, 52, 100, 110, 77,
88, 100, 77, 76, 106, 72, 71, 71, 120, 56, 54, 76, 77, 68, 101, 70,
82, 65, 78, 50, 75, 71, 122, 55, 69, 71, 80, 74, 105, 118, 97, 119,
48, 121, 77, 56, 48, 102, 122, 84, 51, 122, 89, 48, 80, 75, 114, 73,
118, 85, 53, 109, 108, 49, 77, 53, 115, 122, 113, 85, 110, 88, 52, 74,
119, 48, 45, 80, 78, 99, 73, 77, 95, 106, 45, 76, 53, 89, 107, 76,
104, 118, 51, 89, 107, 48, 52, 88, 67, 119, 84, 74, 119, 120, 78, 78,
109, 88, 67, 102, 108, 89, 65, 81, 79, 57, 102, 48, 48, 65, 97, 50,
49, 51, 84, 74, 74, 114, 54, 100, 98, 72, 86, 54, 73, 54, 52, 50,
70, 119, 85, 45, 69, 87, 118, 116, 69, 102, 78, 51, 101, 118, 103, 88,
51, 69, 70, 73, 86, 89, 83, 110, 84, 51, 72, 67, 72, 107, 65, 65,
73, 100, 66, 81, 57, 121, 107, 68, 45, 97, 98, 82, 122, 86, 65, 95,
100, 71, 112, 95, 121, 74, 65, 90, 81, 99, 114, 90, 117, 78, 84, 113,
122, 84, 104, 100, 95, 50, 50, 89, 77, 80, 104, 73, 112, 122, 84, 121,
103, 102, 67, 95, 52, 107, 55, 113, 113, 120, 73, 54, 116, 55, 76, 101,
95, 108, 53, 95, 111, 45, 116, 97, 85, 71, 55, 118, 97, 78, 65, 108,
53, 70, 106, 69, 81]
</t>
</section>
<section title="Plaintext Encryption">
<t>
Encrypt the Plaintext with AES GCM, using the IV,
the CMK as the encryption key, and the "additional authenticated data" value above,
requesting a 128 bit "authentication tag" output.
The resulting Ciphertext is:
</t>
<t>
[253, 237, 181, 180, 97, 161, 105, 207, 233, 120, 65, 100, 45, 122, 246, 116,
195, 212, 102, 37, 36, 175]
</t>
<t>
The resulting "authentication tag" value is:
</t>
<t>
[97, 182, 82, 120, 112, 141, 13, 144, 106, 1, 220, 233, 68, 233, 114, 139]
</t>
</section>
<section title="Encoded JWE Ciphertext">
<t>
Base64url encode the resulting Ciphertext to create the Encoded JWE Ciphertext.
This result is:
</t>
<figure><artwork><![CDATA[_e21tGGhac_peEFkLXr2dMPUZiUkrw]]></artwork></figure>
</section>
<section title="Encoded JWE Integrity Value">
<t>
Base64url encode the resulting "authentication tag" to create the Encoded JWE Integrity Value.
This result is:
</t>
<figure><artwork><![CDATA[YbZSeHCNDZBqAdzpROlyiw]]></artwork></figure>
</section>
<section title="Complete Representation">
<t>
Assemble the final representation:
The Compact Serialization of this result is the
concatenation of the Encoded JWE Header, the Encoded JWE
Encrypted Key, the Encoded JWE Ciphertext, and the Encoded
JWE Integrity Value in that order, with the four strings
being separated by three period ('.') characters.
</t>
<t>
The final result in this example
(with line breaks for display purposes only) is:
</t>
<figure><artwork><![CDATA[eyJhbGciOiJSU0EtT0FFUCIsImVuYyI6IkEyNTZHQ00iLCJpdiI6IjQ4VjFfQUxi
NlVTMDRVM2IifQ.
jvwoyhWxOMboB5cxX6ncAi7Wp3Q5FKRtlmIx35pfR9HpEa6Oy-iEpxEqM30W3YcR
Q8WU9ouRoO5jd6tfdcpX-2X-OteHw4dnMXdMLjHGGx86LMDeFRAN2KGz7EGPJiva
w0yM80fzT3zY0PKrIvU5ml1M5szqUnX4Jw0-PNcIM_j-L5YkLhv3Yk04XCwTJwxN
NmXCflYAQO9f00Aa213TJJr6dbHV6I642FwU-EWvtEfN3evgX3EFIVYSnT3HCHkA
AIdBQ9ykD-abRzVA_dGp_yJAZQcrZuNTqzThd_22YMPhIpzTygfC_4k7qqxI6t7L
e_l5_o-taUG7vaNAl5FjEQ.
_e21tGGhac_peEFkLXr2dMPUZiUkrw.
YbZSeHCNDZBqAdzpROlyiw]]></artwork></figure>
</section>
<section title="Validation">
<t>
This example illustrates the process of creating a JWE with an AEAD algorithm.
These results can be used to validate JWE decryption implementations for these algorithms.
However, note that since the RSAES OAEP computation includes random values,
the results above will not be repeatable.
</t>
</section>
</section>
<section title="Example JWE using RSAES-PKCS1-V1_5 and AES CBC" anchor="RSACBCExample">
<t>
This example encrypts the plaintext
"Now is the time for all good men to come to the aid of their country."
to the recipient using RSAES-PKCS1-V1_5 and AES CBC.
AES CBC does not have an integrated integrity check,
so a separate integrity check calculation is performed using HMAC SHA-256,
with separate encryption and integrity keys being derived from a master key
using the Concat KDF with the SHA-256 digest function.
The representation of this plaintext is:
</t>
<t>
[78, 111, 119, 32, 105, 115, 32, 116, 104, 101, 32, 116, 105, 109, 101, 32,
102, 111, 114, 32, 97, 108, 108, 32, 103, 111, 111, 100, 32, 109, 101, 110,
32, 116, 111, 32, 99, 111, 109, 101, 32, 116, 111, 32, 116, 104, 101, 32,
97, 105, 100, 32, 111, 102, 32, 116, 104, 101, 105, 114, 32, 99, 111, 117,
110, 116, 114, 121, 46]
</t>
<section title="JWE Header">
<t>
The following example JWE Header (with line breaks for display purposes only) declares that:
<list style="symbols">
<t>
the Content Master Key is encrypted to the recipient
using the RSAES-PKCS1-V1_5 algorithm to produce the JWE
Encrypted Key,
</t>
<t>
the Plaintext is encrypted using the AES CBC
algorithm with a 128 bit key to produce the Ciphertext,
</t>
<t>
the JWE Integrity Value safeguarding the integrity of the
Ciphertext and the parameters used to create it was
computed with the HMAC SHA-256 algorithm, and
</t>
<t>
the 128 bit Initialization Vector (IV)
[3, 22, 60, 12, 43, 67, 104, 105, 108, 108, 105, 99, 111, 116, 104, 101]
with the base64url encoding <spanx
style="verb">AxY8DCtDaGlsbGljb3RoZQ</spanx> was used.
</t>
</list>
</t>
<figure><artwork><![CDATA[{"alg":"RSA1_5","enc":"A128CBC","int":"HS256","iv":"AxY8DCtDaGls
bGljb3RoZQ"}]]></artwork></figure>
</section>
<section title="Encoded JWE Header">
<t>
Base64url encoding the bytes of the UTF-8 representation of
the JWE Header yields this Encoded JWE Header value
(with line breaks for display purposes only):
</t>
<figure><artwork><![CDATA[eyJhbGciOiJSU0ExXzUiLCJlbmMiOiJBMTI4Q0JDIiwiaW50IjoiSFMyNTYiLCJp
diI6IkF4WThEQ3REYUdsc2JHbGpiM1JvWlEifQ]]></artwork></figure>
</section>
<section title="Content Master Key (CMK)">
<t>
Generate a random Content Master Key (CMK). In this example, the key value is:
</t>
<t>
[4, 211, 31, 197, 84, 157, 252, 254, 11, 100, 157, 250, 63, 170, 106, 206,
107, 124, 212, 45, 111, 107, 9, 219, 200, 177, 0, 240, 143, 156, 44, 207]
</t>
</section>
<section title="Key Encryption">
<t>
Encrypt the CMK with the recipient's public key using the RSAES-PKCS1-V1_5
algorithm to produce the JWE Encrypted Key.
In this example, the RSA key parameters are:
</t>
<texttable>
<ttcol align="left">Parameter Name</ttcol>
<ttcol align="left">Value</ttcol>
<c>Modulus</c>
<c>
[177, 119, 33, 13, 164, 30, 108, 121, 207, 136, 107, 242, 12, 224, 19, 226,
198, 134, 17, 71, 173, 75, 42, 61, 48, 162, 206, 161, 97, 108, 185, 234,
226, 219, 118, 206, 118, 5, 169, 224, 60, 181, 90, 85, 51, 123, 6, 224,
4, 122, 29, 230, 151, 12, 244, 127, 121, 25, 4, 85, 220, 144, 215, 110,
130, 17, 68, 228, 129, 138, 7, 130, 231, 40, 212, 214, 17, 179, 28, 124,
151, 178, 207, 20, 14, 154, 222, 113, 176, 24, 198, 73, 211, 113, 9, 33,
178, 80, 13, 25, 21, 25, 153, 212, 206, 67, 154, 147, 70, 194, 192, 183,
160, 83, 98, 236, 175, 85, 23, 97, 75, 199, 177, 73, 145, 50, 253, 206,
32, 179, 254, 236, 190, 82, 73, 67, 129, 253, 252, 220, 108, 136, 138, 11,
192, 1, 36, 239, 228, 55, 81, 113, 17, 25, 140, 63, 239, 146, 3, 172,
96, 60, 227, 233, 64, 255, 224, 173, 225, 228, 229, 92, 112, 72, 99, 97,
26, 87, 187, 123, 46, 50, 90, 202, 117, 73, 10, 153, 47, 224, 178, 163,
77, 48, 46, 154, 33, 148, 34, 228, 33, 172, 216, 89, 46, 225, 127, 68,
146, 234, 30, 147, 54, 146, 5, 133, 45, 78, 254, 85, 55, 75, 213, 86,
194, 218, 215, 163, 189, 194, 54, 6, 83, 36, 18, 153, 53, 7, 48, 89,
35, 66, 144, 7, 65, 154, 13, 97, 75, 55, 230, 132, 3, 13, 239, 71]
</c>
<c>Exponent</c>
<c>
[1, 0, 1]
</c>
<c>Private Exponent</c>
<c>
[84, 80, 150, 58, 165, 235, 242, 123, 217, 55, 38, 154, 36, 181, 221, 156,
211, 215, 100, 164, 90, 88, 40, 228, 83, 148, 54, 122, 4, 16, 165, 48,
76, 194, 26, 107, 51, 53, 179, 165, 31, 18, 198, 173, 78, 61, 56, 97,
252, 158, 140, 80, 63, 25, 223, 156, 36, 203, 214, 252, 120, 67, 180, 167,
3, 82, 243, 25, 97, 214, 83, 133, 69, 16, 104, 54, 160, 200, 41, 83,
164, 187, 70, 153, 111, 234, 242, 158, 175, 28, 198, 48, 211, 45, 148, 58,
23, 62, 227, 74, 52, 117, 42, 90, 41, 249, 130, 154, 80, 119, 61, 26,
193, 40, 125, 10, 152, 174, 227, 225, 205, 32, 62, 66, 6, 163, 100, 99,
219, 19, 253, 25, 105, 80, 201, 29, 252, 157, 237, 69, 1, 80, 171, 167,
20, 196, 156, 109, 249, 88, 0, 3, 152, 38, 165, 72, 87, 6, 152, 71,
156, 214, 16, 71, 30, 82, 51, 103, 76, 218, 63, 9, 84, 163, 249, 91,
215, 44, 238, 85, 101, 240, 148, 1, 82, 224, 91, 135, 105, 127, 84, 171,
181, 152, 210, 183, 126, 24, 46, 196, 90, 173, 38, 245, 219, 186, 222, 27,
240, 212, 194, 15, 66, 135, 226, 178, 190, 52, 245, 74, 65, 224, 81, 100,
85, 25, 204, 165, 203, 187, 175, 84, 100, 82, 15, 11, 23, 202, 151, 107,
54, 41, 207, 3, 136, 229, 134, 131, 93, 139, 50, 182, 204, 93, 130, 89]
</c>
</texttable>
<t>
The resulting JWE Encrypted Key value is:
</t>
<t>
[32, 242, 63, 207, 94, 246, 133, 37, 135, 48, 88, 4, 15, 193, 6, 244,
51, 58, 132, 133, 212, 255, 163, 90, 59, 80, 200, 152, 41, 244, 188, 215,
174, 160, 26, 188, 227, 180, 165, 234, 172, 63, 24, 116, 152, 28, 149, 16,
94, 213, 201, 171, 180, 191, 11, 21, 149, 172, 143, 54, 194, 58, 206, 201,
164, 28, 107, 155, 75, 101, 22, 92, 227, 144, 95, 40, 119, 170, 7, 36,
225, 40, 141, 186, 213, 7, 175, 16, 174, 122, 75, 32, 48, 193, 119, 202,
41, 152, 210, 190, 68, 57, 119, 4, 197, 74, 7, 242, 239, 170, 204, 73,
75, 213, 202, 113, 216, 18, 23, 66, 106, 208, 69, 244, 117, 147, 2, 37,
207, 199, 184, 96, 102, 44, 70, 212, 87, 143, 253, 0, 166, 59, 41, 115,
217, 80, 165, 87, 38, 5, 9, 184, 202, 68, 67, 176, 4, 87, 254, 166,
227, 88, 124, 238, 249, 75, 114, 205, 148, 149, 45, 78, 193, 134, 64, 189,
168, 76, 170, 76, 176, 72, 148, 77, 215, 159, 146, 55, 189, 213, 85, 253,
135, 200, 59, 247, 79, 37, 22, 200, 32, 110, 53, 123, 54, 39, 9, 178,
231, 238, 95, 25, 211, 143, 87, 220, 88, 138, 209, 13, 227, 72, 58, 102,
164, 136, 241, 14, 14, 45, 32, 77, 44, 244, 162, 239, 150, 248, 181, 138,
251, 116, 245, 205, 137, 78, 34, 34, 10, 6, 59, 4, 197, 2, 153, 251]
</t>
</section>
<section title="Encoded JWE Encrypted Key">
<t>
Base64url encode the JWE Encrypted Key to produce the Encoded JWE Encrypted Key.
This result (with line breaks for display purposes only) is:
</t>
<figure><artwork><![CDATA[IPI_z172hSWHMFgED8EG9DM6hIXU_6NaO1DImCn0vNeuoBq847Sl6qw_GHSYHJUQ
XtXJq7S_CxWVrI82wjrOyaQca5tLZRZc45BfKHeqByThKI261QevEK56SyAwwXfK
KZjSvkQ5dwTFSgfy76rMSUvVynHYEhdCatBF9HWTAiXPx7hgZixG1FeP_QCmOylz
2VClVyYFCbjKREOwBFf-puNYfO75S3LNlJUtTsGGQL2oTKpMsEiUTdefkje91VX9
h8g7908lFsggbjV7NicJsufuXxnTj1fcWIrRDeNIOmakiPEODi0gTSz0ou-W-LWK
-3T1zYlOIiIKBjsExQKZ-w]]></artwork></figure>
</section>
<section title="Key Derivation">
<t>
Use the Concat key derivation function
to derive Content Encryption Key (CEK)
and Content Integrity Key (CIK) values from the CMK.
The details of this derivation are shown in <xref target="KeyDeriv1Round"/>.
The resulting CEK value is:
</t>
<t>
[249, 255, 87, 218, 224, 223, 221, 53, 204, 121, 166, 130, 195, 184, 50, 69]
</t>
<t>
The resulting CIK value is:
</t>
<t>
[218, 209, 130, 50, 169, 45, 70, 214, 29, 187, 123, 20, 3, 158, 111, 122,
182, 94, 57, 133, 245, 76, 97, 44, 193, 80, 81, 246, 115, 177, 225, 159]
</t>
</section>
<section title="Plaintext Encryption">
<t>
Encrypt the Plaintext with AES CBC using
the CEK and IV to produce the Ciphertext.
The resulting Ciphertext is:
</t>
<t>
[253, 159, 221, 142, 82, 40, 11, 131, 3, 72, 34, 162, 173, 229, 146, 217,
183, 173, 139, 132, 58, 137, 33, 182, 82, 49, 110, 141, 11, 221, 207, 239,
207, 65, 213, 28, 20, 217, 14, 186, 87, 160, 15, 160, 96, 142, 7, 69,
46, 55, 129, 224, 113, 206, 59, 181, 7, 188, 255, 15, 16, 59, 180, 107,
75, 0, 217, 175, 254, 8, 141, 48, 217, 132, 16, 217, 4, 30, 223, 147]
</t>
</section>
<section title="Encoded JWE Ciphertext">
<t>
Base64url encode the resulting Ciphertext to create the Encoded JWE Ciphertext.
This result (with line breaks for display purposes only) is:
</t>
<figure><artwork><![CDATA[_Z_djlIoC4MDSCKireWS2beti4Q6iSG2UjFujQvdz-_PQdUcFNkOulegD6BgjgdF
LjeB4HHOO7UHvP8PEDu0a0sA2a_-CI0w2YQQ2QQe35M]]></artwork></figure>
</section>
<section title="Secured Input Value">
<t>
Concatenate the Encoded JWE Header value, a period character ('.'), the
Encoded JWE Encrypted Key, a second period character, and the
Encoded JWE Ciphertext to create the value to integrity protect.
This result (with line breaks for display purposes only) is:
</t>
<figure><artwork><![CDATA[eyJhbGciOiJSU0ExXzUiLCJlbmMiOiJBMTI4Q0JDIiwiaW50IjoiSFMyNTYiLCJp
diI6IkF4WThEQ3REYUdsc2JHbGpiM1JvWlEifQ.
IPI_z172hSWHMFgED8EG9DM6hIXU_6NaO1DImCn0vNeuoBq847Sl6qw_GHSYHJUQ
XtXJq7S_CxWVrI82wjrOyaQca5tLZRZc45BfKHeqByThKI261QevEK56SyAwwXfK
KZjSvkQ5dwTFSgfy76rMSUvVynHYEhdCatBF9HWTAiXPx7hgZixG1FeP_QCmOylz
2VClVyYFCbjKREOwBFf-puNYfO75S3LNlJUtTsGGQL2oTKpMsEiUTdefkje91VX9
h8g7908lFsggbjV7NicJsufuXxnTj1fcWIrRDeNIOmakiPEODi0gTSz0ou-W-LWK
-3T1zYlOIiIKBjsExQKZ-w.
_Z_djlIoC4MDSCKireWS2beti4Q6iSG2UjFujQvdz-_PQdUcFNkOulegD6BgjgdF
LjeB4HHOO7UHvP8PEDu0a0sA2a_-CI0w2YQQ2QQe35M]]></artwork></figure>
<t>
The representation of this value is:
</t>
<t>
[101, 121, 74, 104, 98, 71, 99, 105, 79, 105, 74, 83, 85, 48, 69, 120,
88, 122, 85, 105, 76, 67, 74, 108, 98, 109, 77, 105, 79, 105, 74, 66,
77, 84, 73, 52, 81, 48, 74, 68, 73, 105, 119, 105, 97, 87, 53, 48,
73, 106, 111, 105, 83, 70, 77, 121, 78, 84, 89, 105, 76, 67, 74, 112,
100, 105, 73, 54, 73, 107, 70, 52, 87, 84, 104, 69, 81, 51, 82, 69,
89, 85, 100, 115, 99, 50, 74, 72, 98, 71, 112, 105, 77, 49, 74, 118,
87, 108, 69, 105, 102, 81, 46, 73, 80, 73, 95, 122, 49, 55, 50, 104,
83, 87, 72, 77, 70, 103, 69, 68, 56, 69, 71, 57, 68, 77, 54, 104,
73, 88, 85, 95, 54, 78, 97, 79, 49, 68, 73, 109, 67, 110, 48, 118,
78, 101, 117, 111, 66, 113, 56, 52, 55, 83, 108, 54, 113, 119, 95, 71,
72, 83, 89, 72, 74, 85, 81, 88, 116, 88, 74, 113, 55, 83, 95, 67,
120, 87, 86, 114, 73, 56, 50, 119, 106, 114, 79, 121, 97, 81, 99, 97,
53, 116, 76, 90, 82, 90, 99, 52, 53, 66, 102, 75, 72, 101, 113, 66,
121, 84, 104, 75, 73, 50, 54, 49, 81, 101, 118, 69, 75, 53, 54, 83,
121, 65, 119, 119, 88, 102, 75, 75, 90, 106, 83, 118, 107, 81, 53, 100,
119, 84, 70, 83, 103, 102, 121, 55, 54, 114, 77, 83, 85, 118, 86, 121,
110, 72, 89, 69, 104, 100, 67, 97, 116, 66, 70, 57, 72, 87, 84, 65,
105, 88, 80, 120, 55, 104, 103, 90, 105, 120, 71, 49, 70, 101, 80, 95,
81, 67, 109, 79, 121, 108, 122, 50, 86, 67, 108, 86, 121, 89, 70, 67,
98, 106, 75, 82, 69, 79, 119, 66, 70, 102, 45, 112, 117, 78, 89, 102,
79, 55, 53, 83, 51, 76, 78, 108, 74, 85, 116, 84, 115, 71, 71, 81,
76, 50, 111, 84, 75, 112, 77, 115, 69, 105, 85, 84, 100, 101, 102, 107,
106, 101, 57, 49, 86, 88, 57, 104, 56, 103, 55, 57, 48, 56, 108, 70,
115, 103, 103, 98, 106, 86, 55, 78, 105, 99, 74, 115, 117, 102, 117, 88,
120, 110, 84, 106, 49, 102, 99, 87, 73, 114, 82, 68, 101, 78, 73, 79,
109, 97, 107, 105, 80, 69, 79, 68, 105, 48, 103, 84, 83, 122, 48, 111,
117, 45, 87, 45, 76, 87, 75, 45, 51, 84, 49, 122, 89, 108, 79, 73,
105, 73, 75, 66, 106, 115, 69, 120, 81, 75, 90, 45, 119, 46, 95, 90,
95, 100, 106, 108, 73, 111, 67, 52, 77, 68, 83, 67, 75, 105, 114, 101,
87, 83, 50, 98, 101, 116, 105, 52, 81, 54, 105, 83, 71, 50, 85, 106,
70, 117, 106, 81, 118, 100, 122, 45, 95, 80, 81, 100, 85, 99, 70, 78,
107, 79, 117, 108, 101, 103, 68, 54, 66, 103, 106, 103, 100, 70, 76, 106,
101, 66, 52, 72, 72, 79, 79, 55, 85, 72, 118, 80, 56, 80, 69, 68,
117, 48, 97, 48, 115, 65, 50, 97, 95, 45, 67, 73, 48, 119, 50, 89,
81, 81, 50, 81, 81, 101, 51, 53, 77]
</t>
</section>
<section title="JWE Integrity Value">
<t>
Compute the HMAC SHA-256 of this value using the CIK to create the JWE Integrity Value.
This result is:
</t>
<t>
[115, 141, 100, 225, 62, 30, 2, 0, 130, 183, 173, 230, 241, 147, 102, 136,
232, 167, 49, 200, 133, 23, 42, 78, 22, 155, 226, 119, 184, 186, 15, 73]
</t>
</section>
<section title="Encoded JWE Integrity Value">
<t>
Base64url encode the resulting JWE Integrity Value to create the Encoded JWE Integrity Value.
This result is:
</t>
<figure><artwork><![CDATA[c41k4T4eAgCCt63m8ZNmiOinMciFFypOFpvid7i6D0k]]></artwork></figure>
</section>
<section title="Complete Representation">
<t>
Assemble the final representation:
The Compact Serialization of this result is the
concatenation of the Encoded JWE Header, the Encoded JWE
Encrypted Key, the Encoded JWE Ciphertext, and the Encoded
JWE Integrity Value in that order, with the four strings
being separated by three period ('.') characters.
</t>
<t>
The final result in this example
(with line breaks for display purposes only) is:
</t>
<figure><artwork><![CDATA[eyJhbGciOiJSU0ExXzUiLCJlbmMiOiJBMTI4Q0JDIiwiaW50IjoiSFMyNTYiLCJp
diI6IkF4WThEQ3REYUdsc2JHbGpiM1JvWlEifQ.
IPI_z172hSWHMFgED8EG9DM6hIXU_6NaO1DImCn0vNeuoBq847Sl6qw_GHSYHJUQ
XtXJq7S_CxWVrI82wjrOyaQca5tLZRZc45BfKHeqByThKI261QevEK56SyAwwXfK
KZjSvkQ5dwTFSgfy76rMSUvVynHYEhdCatBF9HWTAiXPx7hgZixG1FeP_QCmOylz
2VClVyYFCbjKREOwBFf-puNYfO75S3LNlJUtTsGGQL2oTKpMsEiUTdefkje91VX9
h8g7908lFsggbjV7NicJsufuXxnTj1fcWIrRDeNIOmakiPEODi0gTSz0ou-W-LWK
-3T1zYlOIiIKBjsExQKZ-w.
_Z_djlIoC4MDSCKireWS2beti4Q6iSG2UjFujQvdz-_PQdUcFNkOulegD6BgjgdF
LjeB4HHOO7UHvP8PEDu0a0sA2a_-CI0w2YQQ2QQe35M.
c41k4T4eAgCCt63m8ZNmiOinMciFFypOFpvid7i6D0k]]></artwork></figure>
</section>
<section title="Validation">
<t>
This example illustrates the process of creating a JWE with a non-AEAD algorithm.
These results can be used to validate JWE decryption implementations for these algorithms.
Since all the algorithms used in this example produce deterministic results,
the results above should be repeatable.
</t>
</section>
</section>
<section title="Example Key Derivation with Outputs <= Hash Size" anchor="KeyDeriv1Round">
<t>
This example uses the Concat KDF to derive the
Content Encryption Key (CEK) and Content Integrity Key (CIK)
from the Content Master Key (CMK) in the manner described in
Section 4.12 of <xref target="JWA"/>.
In this example,
a 256 bit CMK is used to derive a 128 bit CEK and a 256 bit CIK.
</t>
<t>
The CMK value is:
</t>
<t>
[4, 211, 31, 197, 84, 157, 252, 254, 11, 100, 157, 250, 63, 170, 106, 206,
107, 124, 212, 45, 111, 107, 9, 219, 200, 177, 0, 240, 143, 156, 44, 207]
</t>
<section title="CEK Generation">
<t>
When deriving the CEK from the CMK, the ASCII label "Encryption"
([69, 110, 99, 114, 121, 112, 116, 105, 111, 110]) is used.
The input to the first hash round is the concatenation of the
big endian number 1 ([0, 0, 0, 1]), the CMK, and the label.
Thus the round 1 hash input is:
</t>
<t>
[0, 0, 0, 1, 4, 211, 31, 197, 84, 157, 252, 254, 11, 100, 157, 250,
63, 170, 106, 206, 107, 124, 212, 45, 111, 107, 9, 219, 200, 177, 0, 240,
143, 156, 44, 207, 69, 110, 99, 114, 121, 112, 116, 105, 111, 110]
</t>
<t>
The SHA-256 hash of this value, which is the round 1 hash output, is:
</t>
<t>
[249, 255, 87, 218, 224, 223, 221, 53, 204, 121, 166, 130, 195, 184, 50, 69,
11, 237, 202, 71, 10, 96, 59, 199, 140, 88, 126, 147, 146, 113, 222, 41]
</t>
<t>
Given that 128 bits are needed for the CEK and the hash has produced 256 bits,
the CEK value is the first 128 bits of that value:
</t>
<t>
[249, 255, 87, 218, 224, 223, 221, 53, 204, 121, 166, 130, 195, 184, 50, 69]
</t>
</section>
<section title="CIK Generation">
<t>
When deriving the CIK from the CMK, the ASCII label "Integrity"
([73, 110, 116, 101, 103, 114, 105, 116, 121]) is used.
The input to the first hash round is the concatenation of the
big endian number 1 ([0, 0, 0, 1]), the CMK, and the label.
Thus the round 1 hash input is:
</t>
<t>
[0, 0, 0, 1, 4, 211, 31, 197, 84, 157, 252, 254, 11, 100, 157, 250,
63, 170, 106, 206, 107, 124, 212, 45, 111, 107, 9, 219, 200, 177, 0, 240,
143, 156, 44, 207, 73, 110, 116, 101, 103, 114, 105, 116, 121]
</t>
<t>
The SHA-256 hash of this value, which is the round 1 hash output, is:
</t>
<t>
[218, 209, 130, 50, 169, 45, 70, 214, 29, 187, 123, 20, 3, 158, 111, 122,
182, 94, 57, 133, 245, 76, 97, 44, 193, 80, 81, 246, 115, 177, 225, 159]
</t>
<t>
Given that 256 bits are needed for the CIK and the hash has produced 256 bits,
the CIK value is that same value:
</t>
<t>
[218, 209, 130, 50, 169, 45, 70, 214, 29, 187, 123, 20, 3, 158, 111, 122,
182, 94, 57, 133, 245, 76, 97, 44, 193, 80, 81, 246, 115, 177, 225, 159]
</t>
</section>
</section>
<section title="Example Key Derivation with Outputs >= Hash Size" anchor="KeyDeriv2Round">
<t>
This example uses the Concat KDF to derive the
Content Encryption Key (CEK) and Content Integrity Key (CIK)
from the Content Master Key (CMK) in the manner described in
Section 4.12 of <xref target="JWA"/>.
In this example,
a 512 bit CMK is used to derive a 256 bit CEK and a 512 bit CIK.
</t>
<t>
The CMK value is:
</t>
<t>
[148, 116, 199, 126, 2, 117, 233, 76, 150, 149, 89, 193, 61, 34, 239, 226,
109, 71, 59, 160, 192, 140, 150, 235, 106, 204, 49, 176, 68, 119, 13, 34,
49, 19, 41, 69, 5, 20, 252, 145, 104, 129, 137, 138, 67, 23, 153, 83,
81, 234, 82, 247, 48, 211, 41, 130, 35, 124, 45, 156, 249, 7, 225, 168]
</t>
<section title="CEK Generation">
<t>
When deriving the CEK from the CMK, the ASCII label "Encryption"
([69, 110, 99, 114, 121, 112, 116, 105, 111, 110]) is used.
The input to the first hash round is the concatenation of the
big endian number 1 ([0, 0, 0, 1]), the CMK, and the label.
Thus the round 1 hash input is:
</t>
<t>
[0, 0, 0, 1, 148, 116, 199, 126, 2, 117, 233, 76, 150, 149, 89, 193,
61, 34, 239, 226, 109, 71, 59, 160, 192, 140, 150, 235, 106, 204, 49, 176,
68, 119, 13, 34, 49, 19, 41, 69, 5, 20, 252, 145, 104, 129, 137, 138,
67, 23, 153, 83, 81, 234, 82, 247, 48, 211, 41, 130, 35, 124, 45, 156,
249, 7, 225, 168, 69, 110, 99, 114, 121, 112, 116, 105, 111, 110]
</t>
<t>
The SHA-256 hash of this value, which is the round 1 hash output, is:
</t>
<t>
[137, 5, 92, 9, 17, 47, 17, 86, 253, 235, 34, 247, 121, 78, 11, 144,
10, 172, 38, 247, 108, 243, 201, 237, 95, 80, 49, 150, 116, 240, 159, 64]
</t>
<t>
Given that 256 bits are needed for the CEK and the hash has produced 256 bits,
the CEK value is that same value:
</t>
<t>
[137, 5, 92, 9, 17, 47, 17, 86, 253, 235, 34, 247, 121, 78, 11, 144,
10, 172, 38, 247, 108, 243, 201, 237, 95, 80, 49, 150, 116, 240, 159, 64]
</t>
</section>
<section title="CIK Generation">
<t>
When deriving the CIK from the CMK, the ASCII label "Integrity"
([73, 110, 116, 101, 103, 114, 105, 116, 121]) is used.
The input to the first hash round is the concatenation of the
big endian number 1 ([0, 0, 0, 1]), the CMK, and the label.
Thus the round 1 hash input is:
</t>
<t>
[0, 0, 0, 1, 148, 116, 199, 126, 2, 117, 233, 76, 150, 149, 89, 193,
61, 34, 239, 226, 109, 71, 59, 160, 192, 140, 150, 235, 106, 204, 49, 176,
68, 119, 13, 34, 49, 19, 41, 69, 5, 20, 252, 145, 104, 129, 137, 138,
67, 23, 153, 83, 81, 234, 82, 247, 48, 211, 41, 130, 35, 124, 45, 156,
249, 7, 225, 168, 73, 110, 116, 101, 103, 114, 105, 116, 121]
</t>
<t>
The SHA-256 hash of this value, which is the round 1 hash output, is:
</t>
<t>
[11, 179, 132, 177, 171, 24, 126, 19, 113, 1, 200, 102, 100, 74, 88, 149,
31, 41, 71, 57, 51, 179, 106, 242, 113, 211, 56, 56, 37, 198, 57, 17]
</t>
<t>
Given that 512 bits are needed for the CIK and the hash has produced only 256 bits,
another round is needed.
The input to the second hash round is the concatenation of the
big endian number 2 ([0, 0, 0, 2]), the CMK, and the label.
Thus the round 2 hash input is:
</t>
<t>
[0, 0, 0, 2, 148, 116, 199, 126, 2, 117, 233, 76, 150, 149, 89, 193,
61, 34, 239, 226, 109, 71, 59, 160, 192, 140, 150, 235, 106, 204, 49, 176,
68, 119, 13, 34, 49, 19, 41, 69, 5, 20, 252, 145, 104, 129, 137, 138,
67, 23, 153, 83, 81, 234, 82, 247, 48, 211, 41, 130, 35, 124, 45, 156,
249, 7, 225, 168, 73, 110, 116, 101, 103, 114, 105, 116, 121]
</t>
<t>
The SHA-256 hash of this value, which is the round 2 hash output, is:
</t>
<t>
[149, 209, 221, 113, 40, 191, 95, 252, 142, 254, 141, 230, 39, 113, 139, 84,
44, 156, 247, 47, 223, 101, 229, 180, 82, 231, 38, 96, 170, 119, 236, 81]
</t>
<t>
Given that 512 bits are needed for the CIK and the two rounds have
collectively produced 512 bits of output, the CIK is the
concatenation of the round 1 and round 2 hash outputs, which is:
</t>
<t>
[11, 179, 132, 177, 171, 24, 126, 19, 113, 1, 200, 102, 100, 74, 88, 149,
31, 41, 71, 57, 51, 179, 106, 242, 113, 211, 56, 56, 37, 198, 57, 17,
149, 209, 221, 113, 40, 191, 95, 252, 142, 254, 141, 230, 39, 113, 139, 84,
44, 156, 247, 47, 223, 101, 229, 180, 82, 231, 38, 96, 170, 119, 236, 81]
</t>
</section>
</section>
</section>
<section title="Acknowledgements" anchor="Acknowledgements">
<t>
Solutions for encrypting JSON content were also explored by
<xref target="JSE">JSON Simple Encryption</xref> and
<xref target="I-D.rescorla-jsms">JavaScript Message Security
Format</xref>, both of which significantly influenced this draft.
This draft attempts to explicitly reuse as many of the relevant concepts from
<xref target="W3C.CR-xmlenc-core1-20120313">XML Encryption 1.1</xref>
and <xref target="RFC5652">RFC 5652</xref> as possible,
while utilizing simple compact JSON-based data structures.
</t>
<t>
Special thanks are due to John Bradley and Nat Sakimura for
the discussions that helped inform the content of this
specification and to Eric Rescorla and Joe Hildebrand for
allowing the reuse of text from <xref
target="I-D.rescorla-jsms"/> in this document.
</t>
<t>
My thanks to Axel Nennker, Emmanuel Raviart, Brian Campbell, and Edmund Jay
for validating the examples in this specification.
</t>
</section>
<section title='Document History'>
<t>
[[ to be removed by the RFC editor before publication as an RFC ]]
</t>
<t>
-03
<list style='symbols'>
<t>
Added the <spanx style="verb">kdf</spanx> (key derivation function) header parameter
to provide crypto agility for key derivation.
The default KDF remains the Concat KDF with the SHA-256 digest function.
</t>
<t>
Reordered encryption steps so that the Encoded JWE Header
is always created before it is needed as an input to the AEAD
"additional authenticated data" parameter.
</t>
<t>
Added the <spanx style="verb">cty</spanx> (content type) header parameter
for declaring type information about the secured content,
as opposed to the <spanx style="verb">typ</spanx> (type) header parameter,
which declares type information about this object.
</t>
<t>
Moved description of how to determine whether a header is
for a JWS or a JWE from the JWT spec to the JWE spec.
</t>
<t>
Added complete encryption examples for both AEAD and non-AEAD algorithms.
</t>
<t>
Added complete key derivation examples.
</t>
<t>
Added "Collision Resistant Namespace" to the terminology section.
</t>
<t>
Reference ITU.X690.1994 for DER encoding.
</t>
<t>
Added Registry Contents sections to populate registry values.
</t>
<t>
Numerous editorial improvements.
</t>
</list>
</t>
<t>
-02
<list style='symbols'>
<t>
When using AEAD algorithms (such as AES GCM),
use the "additional authenticated data" parameter
to provide integrity for the header, encrypted key, and
ciphertext and use the resulting "authentication tag"
value as the JWE Integrity Value.
</t>
<t>
Defined KDF output key sizes.
</t>
<t>
Generalized text to allow key agreement to be employed
as an alternative to key wrapping or key encryption.
</t>
<t>
Changed compression algorithm from gzip to DEFLATE.
</t>
<t>
Clarified that it is an error when a <spanx style="verb">kid</spanx>
value is included and no matching key is found.
</t>
<t>
Clarified that JWEs with duplicate Header Parameter Names
MUST be rejected.
</t>
<t>
Clarified the relationship between
<spanx style="verb">typ</spanx> header parameter values
and MIME types.
</t>
<t>
Registered application/jwe MIME type and "JWE" typ header parameter value.
</t>
<t>
Simplified JWK terminology to get replace the "JWK Key Object" and
"JWK Container Object" terms with simply "JSON Web Key (JWK)"
and "JSON Web Key Set (JWK Set)" and to eliminate potential
confusion between single keys and sets of keys.
As part of this change, the header parameter name for a
public key value was changed from
<spanx style="verb">jpk</spanx> (JSON Public Key) to
<spanx style="verb">jwk</spanx> (JSON Web Key).
</t>
<t>
Added suggestion on defining additional header parameters
such as <spanx style="verb">x5t#S256</spanx> in the future
for certificate thumbprints using hash algorithms other
than SHA-1.
</t>
<t>
Specify RFC 2818 server identity validation, rather than
RFC 6125 (paralleling the same decision in the OAuth specs).
</t>
<t>
Generalized language to refer to Message Authentication Codes (MACs)
rather than Hash-based Message Authentication Codes (HMACs)
unless in a context specific to HMAC algorithms.
</t>
<t>
Reformatted to give each header parameter its own section heading.
</t>
</list>
</t>
<t>
-01
<list style='symbols'>
<t>
Added an integrity check for non-AEAD algorithms.
</t>
<t>
Added <spanx style="verb">jpk</spanx> and <spanx
style="verb">x5c</spanx> header parameters for including
JWK public keys and X.509 certificate chains directly in
the header.
</t>
<t>
Clarified that this specification is defining the JWE
Compact Serialization. Referenced the new JWE-JS spec,
which defines the JWE JSON Serialization.
</t>
<t>
Added text "New header parameters should be introduced
sparingly since an implementation that does not understand
a parameter MUST reject the JWE".
</t>
<t>
Clarified that the order of the encryption and decryption
steps is not significant in cases where there are no
dependencies between the inputs and outputs of the steps.
</t>
<t>
Made other editorial improvements suggested by JOSE
working group participants.
</t>
</list>
</t>
<t>
-00
<list style='symbols'>
<t>
Created the initial IETF draft based upon
draft-jones-json-web-encryption-02 with no normative
changes.
</t>
<t>
Changed terminology to no longer call both digital
signatures and HMACs "signatures".
</t>
</list>
</t>
</section>
</back>
</rfc>
| PAFTECH AB 2003-2026 | 2026-04-22 20:43:51 |