BT4PT-EncryptedDataV1-0

Module Info

Reference: BT4PT-EncryptedDataV1-0
Numeric OID: 1.3.6.1.4.1.17218.1.2.11.1.0

Exports

This module explicitly exports the following symbols:

EncryptedData encryptedData

Imports

From BT4PT-GeneralElementsV1-0

GenericId CompanyCode DATA-ELEMENT Data cuperEncoding

From BT4PT-CertificatesV1-0

luggageTag

Assignments

EncryptedData

SEQUENCE

This sequence contains the following fields:

header: EncryptedDataHeader
ciphertext: The encrypted data. A new 128-bit Content Encryption Key SHALL be generated uniformly at random for every EncryptedData value and SHALL NOT be reused. The ciphertext uses AES-128-GCM encryption with a nonce of 12 null bytes and associated data being the CUPER encoding of EncryptedDataHeader. The value, after decryption SHALL be the CUPER encoding of InnerData.

OCTET STRING

encryptedData

OBJECT

This is an object of the class: DATA-ELEMENT

This object has the following field values:

&id: ENC1
&Type: EncryptedData
&encoding: cuperEncoding
&Constraints: NULL

EncryptedDataHeader

SEQUENCE

This sequence contains the following fields:

ephemeralPublicKey: An X25519 ephemeral public key.

OCTET STRING
This type is constrained in the following way:

Size

The length of the value must exactly: 32
recipients: SEQUENCE OF
This type is constrained in the following way:

Size

The length of the value must be greater than or equal to: 1

The length of the value must be less than or equal to: 32

Recipient

Recipient

SEQUENCE

This sequence contains the following fields:

key

RecipientKey

wrappedKey

The 128-bit Content Encryption Key, wrapped according to RFC 3394. The wrapping key is derived as follows:

let SK be the result of the X25519 exchange between the ephemeral key and the long term key identified by (securityProvider, keyId).
if SK is the all-zero 32-byte string, the key agreement SHALL be considered to have failed.
the wrapping key is the output of HKDF-SHA256(SK, length=32 bytes, salt=ephemeralPublicKey, info="BT4PT-EncryptedDataV1-0" || CUPER(RecipientKey))

OCTET STRING

This type is constrained in the following way:

Size

The length of the value must exactly: 24

RecipientKey

SEQUENCE

This sequence contains the following fields:

securityProvider: CompanyCode
keyId: INTEGER
This type is constrained in the following way:

Range

The value must be greater than or equal to: 1

The value must be less than or equal to: 65536

InnerData

SEQUENCE OF

This type is constrained in the following way:

Size

The length of the value must be greater than or equal to: 1

The length of the value must be less than or equal to: 16

Data

This type is concretely parameterised with the following:

ElementSet: EncryptedDataElements

This type is constrained in the following way:

Fields

The type must satisfy the following field constraints, other fields are unconstrained:

Field	Presence	Value
format	No stipulation	Inverse Any value, except any satisfying the following: Union Any of the following can be true: Single value The value must be exactly: `!I` OR Single value The value must be exactly: `!C` OR Single value The value must be exactly: `!P`

EncryptedDataElements

OBJECT SET

This object set has the following members:

&id	&Type	&encoding	&Constraints
`LUG1`	LuggageTag	cuperEncoding	NULL
Other members may be added at runtime.

/**
* BT4PT Encrypted Data - DRAFT.
*/
BT4PT-EncryptedDataV1-0 {
    iso(1) identified-organization(3) dod(6) internet(1) private(4) enterprise(1) uic(17218) fcb(1) bt4pt(2) encryptedData(11) v1(1) 0
} DEFINITIONS ::= BEGIN

EXPORTS EncryptedData, encryptedData;

IMPORTS GenericId, CompanyCode, DATA-ELEMENT, Data, cuperEncoding
 FROM BT4PT-GeneralElementsV1-0 { iso(1) identified-organization(3) dod(6) internet(1) private(4) enterprise(1) uic(17218) fcb(1) bt4pt(2) general(1) v1(1) 0 }
 luggageTag
 FROM BT4PT-CertificatesV1-0 { iso(1) identified-organization(3) dod(6) internet(1) private(4) enterprise(1) uic(17218) fcb(1) bt4pt(2) luggageTag(12) v1(1) 0 };

EncryptedData ::= SEQUENCE {
    header      EncryptedDataHeader,
    /**
    * The encrypted data.
    * A new 128-bit Content Encryption Key **SHALL** be generated uniformly at random for every `EncryptedData` value and **SHALL NOT** be reused.
    * The ciphertext uses AES-128-GCM encryption with a nonce of 12 null bytes and associated data being the CUPER encoding of `EncryptedDataHeader`.
    * The value, after decryption **SHALL** be the CUPER encoding of {@link InnerData}.
    */
    ciphertext  OCTET STRING
}

encryptedData DATA-ELEMENT ::= { EncryptedData IDENTIFIED BY "ENC1" ENCODED WITH cuperEncoding CONSTRAINED BY NULL }

EncryptedDataHeader ::= SEQUENCE {
    /**
    * An X25519 ephemeral public key.
    */
    ephemeralPublicKey  OCTET STRING (SIZE(32)),
    recipients          SEQUENCE SIZE(1..32) OF Recipient
}

Recipient ::= SEQUENCE {
    key         RecipientKey,
    /**
    * The 128-bit Content Encryption Key, wrapped according to [RFC 3394](https://datatracker.ietf.org/doc/html/rfc3394.html).
    * The wrapping key is derived as follows:
    * - let `SK` be the result of the X25519 exchange between the ephemeral key and the long term key identified by `(securityProvider, keyId)`.
    * - if `SK` is the all-zero 32-byte string, the key agreement **SHALL** be considered to have failed.
    * - the wrapping key is the output of `HKDF-SHA256(SK, length=32 bytes, salt=ephemeralPublicKey, info="BT4PT-EncryptedDataV1-0" || CUPER(RecipientKey))`
    */
    wrappedKey  OCTET STRING (SIZE(24))
}

RecipientKey ::= SEQUENCE {
    securityProvider    CompanyCode,
    keyId               INTEGER (1..65536)
}

InnerData ::= SEQUENCE (SIZE(1..16)) OF Data{{EncryptedDataElements}} (WITH COMPONENTS {
    ...,
    format (ALL EXCEPT ("!I" | "!C" | "!P"))
})

EncryptedDataElements DATA-ELEMENT ::= {
    luggageTag,
    ...
}

END

Module Info

Exports

Imports

From BT4PT-GeneralElementsV1-0

From BT4PT-CertificatesV1-0

Assignments

EncryptedData

encryptedData

EncryptedDataHeader

Size

Size

Recipient

Size

RecipientKey

Range

InnerData

Size

Fields

Inverse

Union

Single value

Single value

Single value

EncryptedDataElements