gose/cose

Typed accessors and builders for COSE message header parameters.

Phantom-state vocabulary

Each COSE message module uses a phantom state type named after the RFC 9052 operation it performs: Sign1 uses Unsigned/Signed, Encrypt0 and Encrypt use Unencrypted/Encrypted, Mac0 uses Untagged/Tagged, and Sign uses Building/Signed for its builder body. The names match the RFC terminology rather than a single uniform vocabulary.

Types

ContentType

</>

Well-known CoAP content format identifiers and media type strings used in the COSE content type header (label 3).

pub type ContentType {
  TextPlain
  OctetStream
  Json
  Cbor
  Cwt
  CoseSign
  CoseSign1
  CoseEncrypt
  CoseEncrypt0
  CoseMac
  CoseMac0
  CoseKey
  CoseKeySet
  IntContentType(Int)
  TextContentType(String)
}

Constructors

```
TextPlain
```
```
OctetStream
```
```
Json
```
```
Cbor
```
```
Cwt
```
```
CoseSign
```
```
CoseSign1
```
```
CoseEncrypt
```
```
CoseEncrypt0
```
```
CoseMac
```
```
CoseMac0
```
```
CoseKey
```
```
CoseKeySet
```
```
IntContentType(Int)
```
```
TextContentType(String)
```

</>

A COSE header parameter with typed labels and values for well-known headers, plus an Unknown fallback for non-standard parameters.

pub type Header {
  Alg(Int)
  Crit(List(Int))
  ContentType(ContentType)
  Kid(BitArray)
  Iv(BitArray)
  PartialIv(BitArray)
  Unknown(cbor.Value, cbor.Value)
}

Constructors

```
Alg(Int)
```
```
Crit(List(Int))
```
```
ContentType(ContentType)
```
```
Kid(BitArray)
```
```
Iv(BitArray)
```
```
PartialIv(BitArray)
```
```
Unknown(cbor.Value, cbor.Value)
```

Values

algorithm

</>

pub fn algorithm(
  headers: List(Header),
) -> Result(Int, gose.GoseError)

Extract the algorithm identifier (label 1).

content_type

</>

pub fn content_type(
  headers: List(Header),
) -> Result(ContentType, gose.GoseError)

Extract the content type (label 3).

critical

</>

pub fn critical(
  headers: List(Header),
) -> Result(List(Int), gose.GoseError)

Extract the critical headers list (label 2).

iv

</>

pub fn iv(
  headers: List(Header),
) -> Result(BitArray, gose.GoseError)

Extract the IV (label 5).

kid

</>

pub fn kid(
  headers: List(Header),
) -> Result(BitArray, gose.GoseError)

Extract the key ID (label 4).

partial_iv

</>

pub fn partial_iv(
  headers: List(Header),
) -> Result(BitArray, gose.GoseError)

Extract the partial IV (label 6).