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use core::fmt;
#[cfg(feature = "dev")]
use arbitrary::Arbitrary;
use meadowcap::DoesNotAuthorise;
use willow_data_model::prelude as wdm;
use crate::prelude::*;
wrapper! {
/// An [authorisation token](https://willowprotocol.org/specs/data-model/index.html#AuthorisationToken), cryptographically certifying that an entry was created by somebody who had the permission to do so.
///
/// #### Examples
///
/// Authorising an entry of your own:
///
/// ```
/// use rand::rngs::OsRng;
/// use willow25::prelude::*;
/// use willow25::authorisation::raw::*;
///
/// # #[cfg(feature = "dev")] {
/// let mut csprng = OsRng;
/// let (subspace_id, secret) = randomly_generate_subspace(&mut csprng);
/// let namespace_id = NamespaceId::from_bytes(&[17; 32]);
///
/// let my_entry = Entry::builder()
/// .namespace_id(namespace_id.clone())
/// .subspace_id(subspace_id.clone())
/// .path(path!("/ideas"))
/// .timestamp(12345)
/// .payload(b"chocolate with mustard")
/// .build().unwrap();
///
/// let mut cap = WriteCapability::new_communal(
/// namespace_id.clone(),
/// subspace_id.clone(),
/// );
///
/// let auth_token = AuthorisationToken::new_for_entry(&my_entry, &cap, &secret).unwrap();
///
/// assert!(auth_token.does_authorise(&my_entry));
/// # }
/// ```
///
/// Verifying an untrusted entry, creating the authorisation token from raw parts, which fails if those parts are invalid:
///
/// ```
/// use rand::rngs::OsRng;
/// use willow25::prelude::*;
/// use willow25::authorisation::raw::*;
///
/// # #[cfg(feature = "dev")] {
/// let mut csprng = OsRng;
/// let (subspace_id, secret) = randomly_generate_subspace(&mut csprng);
/// let namespace_id = NamespaceId::from_bytes(&[17; 32]);
///
/// let my_entry = Entry::builder()
/// .namespace_id(namespace_id.clone())
/// .subspace_id(subspace_id.clone())
/// .path(path!("/ideas"))
/// .timestamp(12345)
/// .payload(b"chocolate with mustard")
/// .build().unwrap();
///
/// let mut cap = WriteCapability::new_communal(
/// namespace_id.clone(),
/// subspace_id.clone(),
/// );
///
/// let auth_token = AuthorisationToken::new(
/// cap,
/// SubspaceSignature::from([18; 64]), // Invalid signature, verification will fail.
/// );
///
/// assert!(!auth_token.does_authorise(&my_entry));
/// # }
/// ```
#[derive(PartialEq, Eq, Clone)]
#[cfg_attr(feature = "dev", derive(Arbitrary))]
AuthorisationToken; meadowcap::McAuthorisationToken<MCL, MCC, MPL, NamespaceId, NamespaceSignature, SubspaceId, SubspaceSignature, SubspaceSecret>
}
impl fmt::Debug for AuthorisationToken {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
self.0.fmt(f)
}
}
impl AuthorisationToken {
/// Manually creates a new [`AuthorisationToken`] from a write capability and a signature (as opposed to using [`AuthorisationToken::new_for_entry`](AuthorisationToken::new_for_entry) to create the correct signature yourself).
///
/// ```
/// use rand::rngs::OsRng;
/// use willow25::prelude::*;
/// use willow25::authorisation::raw::*;
///
/// # #[cfg(feature = "dev")] {
/// let mut csprng = OsRng;
/// let (subspace_id, secret) = randomly_generate_subspace(&mut csprng);
/// let namespace_id = NamespaceId::from_bytes(&[17; 32]);
///
/// let my_entry = Entry::builder()
/// .namespace_id(namespace_id.clone())
/// .subspace_id(subspace_id.clone())
/// .path(path!("/ideas"))
/// .timestamp(12345)
/// .payload(b"chocolate with mustard")
/// .build().unwrap();
///
/// let mut cap = WriteCapability::new_communal(
/// namespace_id.clone(),
/// subspace_id.clone(),
/// );
///
/// let auth_token = AuthorisationToken::new(
/// cap,
/// SubspaceSignature::from([18; 64]), // Invalid signature, verification will fail.
/// );
///
/// assert!(!auth_token.does_authorise(&my_entry));
/// # }
/// ```
pub fn new(capability: WriteCapability, signature: SubspaceSignature) -> Self {
meadowcap::McAuthorisationToken::new(capability.into(), signature).into()
}
/// Returns a reference to the write capability.
pub fn capability(&self) -> &WriteCapability {
self.0.capability().into()
}
/// Returns a reference to the signature.
pub fn signature(&self) -> &SubspaceSignature {
self.0.signature()
}
/// Takes ownership of the authorisation token and returns its capability and signature by value.
pub fn into_parts(self) -> (WriteCapability, SubspaceSignature) {
let (cap, sig) = self.0.into_parts();
(cap.into(), sig)
}
/// Creates an authorisation token for a given entry and capability by computing the correct signature from the given secret.
///
/// Returns an error if the capability does not grant write access to the entry being authorised.
///
/// ```
/// use rand::rngs::OsRng;
/// use willow25::prelude::*;
/// use willow25::authorisation::raw::*;
///
/// # #[cfg(feature = "dev")] {
/// let mut csprng = OsRng;
/// let (subspace_id, secret) = randomly_generate_subspace(&mut csprng);
/// let namespace_id = NamespaceId::from_bytes(&[17; 32]);
///
/// let my_entry = Entry::builder()
/// .namespace_id(namespace_id.clone())
/// .subspace_id(subspace_id.clone())
/// .path(path!("/ideas"))
/// .timestamp(12345)
/// .payload(b"chocolate with mustard")
/// .build().unwrap();
///
/// let mut cap = WriteCapability::new_communal(
/// namespace_id.clone(),
/// subspace_id.clone(),
/// );
///
/// let auth_token = AuthorisationToken::new_for_entry(&my_entry, &cap, &secret).unwrap();
///
/// assert!(auth_token.does_authorise(&my_entry));
/// # }
/// ```
pub fn new_for_entry<E>(
entry: &E,
write_capability: &WriteCapability,
secret: &SubspaceSecret,
) -> Result<Self, DoesNotAuthorise>
where
E: EntrylikeExt + ?Sized,
{
match McIngredients::new(write_capability.clone(), secret.clone()) {
Some(ingredients) => wdm::AuthorisationToken::<
MCL,
MCC,
MPL,
NamespaceId,
SubspaceId,
PayloadDigest,
>::new_for_entry(entry, &ingredients),
None => Err(DoesNotAuthorise),
}
}
/// Return `true` iff `self` is a valid authorisation token for the given entry.
///
/// ```
/// use rand::rngs::OsRng;
/// use willow25::prelude::*;
/// use willow25::authorisation::raw::*;
///
/// # #[cfg(feature = "dev")] {
/// let mut csprng = OsRng;
/// let (subspace_id, secret) = randomly_generate_subspace(&mut csprng);
/// let namespace_id = NamespaceId::from_bytes(&[17; 32]);
///
/// let my_entry = Entry::builder()
/// .namespace_id(namespace_id.clone())
/// .subspace_id(subspace_id.clone())
/// .path(path!("/ideas"))
/// .timestamp(12345)
/// .payload(b"chocolate with mustard")
/// .build().unwrap();
///
/// let mut cap = WriteCapability::new_communal(
/// namespace_id.clone(),
/// subspace_id.clone(),
/// );
///
/// let auth_token = AuthorisationToken::new_for_entry(&my_entry, &cap, &secret).unwrap();
///
/// assert!(auth_token.does_authorise(&my_entry));
/// # }
/// ```
pub fn does_authorise<E>(&self, entry: &E) -> bool
where
E: wdm::EntrylikeExt<MCL, MCC, MPL, NamespaceId, SubspaceId, PayloadDigest> + ?Sized,
{
wdm::AuthorisationToken::<MCL, MCC, MPL, NamespaceId, SubspaceId, PayloadDigest>::does_authorise(&self.0, entry)
}
}
/// You only need this trait impl if you work with fully generic code from the [`willow_data_model`] crate.
impl wdm::AuthorisationToken<MCL, MCC, MPL, NamespaceId, SubspaceId, PayloadDigest>
for AuthorisationToken
{
type Ingredients = McIngredients;
type CreationError = DoesNotAuthorise;
fn new_for_entry<E>(
entry: &E,
ingredients: &Self::Ingredients,
) -> Result<Self, Self::CreationError>
where
E: wdm::EntrylikeExt<MCL, MCC, MPL, NamespaceId, SubspaceId, PayloadDigest> + ?Sized,
{
meadowcap::McAuthorisationToken::<
MCL,
MCC,
MPL,
NamespaceId,
NamespaceSignature,
SubspaceId,
SubspaceSignature,
SubspaceSecret,
>::new_for_entry(entry, ingredients.into())
.map(Into::into)
}
fn does_authorise<E>(&self, entry: &E) -> bool
where
E: wdm::EntrylikeExt<MCL, MCC, MPL, NamespaceId, SubspaceId, PayloadDigest> + ?Sized,
{
self.0.does_authorise(entry)
}
}
wrapper! {
/// Only needed if you work with fully generic code from the [`willow_data_model`] crate; the ingredients for the [`willow_data_model::authorisation::AuthorisationToken`] impl of [`AuthorisationToken`].
#[derive(PartialEq, Eq, Clone)]
#[cfg_attr(feature = "dev", derive(Arbitrary))]
McIngredients; meadowcap::McIngredients<MCL, MCC, MPL, NamespaceId, NamespaceSignature, SubspaceId, SubspaceSignature, SubspaceSecret>
}
impl fmt::Debug for McIngredients {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
self.0.fmt(f)
}
}
impl McIngredients {
/// Returns a reference to the write capability.
pub fn capability(&self) -> &WriteCapability {
self.0.capability().into()
}
/// Returns a reference to the keypair.
pub fn keypair(&self) -> &SubspaceSecret {
self.0.keypair()
}
/// Takes ownership of the ingredients and returns the capability and keypair by value.
pub fn into_parts(self) -> (WriteCapability, SubspaceSecret) {
let (cap, secret) = self.0.into_parts();
(cap.into(), secret)
}
/// Creates new [`McIngredients`], returning `None` if the keypair does not match the receiver of the capability.
///
/// ```
/// use rand::rngs::OsRng;
/// use willow25::prelude::*;
/// use willow25::authorisation::McIngredients;
///
/// # #[cfg(feature = "dev")] {
/// let mut csprng = OsRng;
/// let (subspace_id, secret) = randomly_generate_subspace(&mut csprng);
/// let (_subspace_id2, secret2) = randomly_generate_subspace(&mut csprng);
/// let namespace_id = NamespaceId::from_bytes(&[17; 32]);
///
/// let mut cap = WriteCapability::new_communal(
/// namespace_id.clone(),
/// subspace_id.clone(),
/// );
///
/// assert!(McIngredients::new(cap.clone(), secret).is_some());
/// assert!(McIngredients::new(cap.clone(), secret2).is_none());
/// # }
/// ```
pub fn new(capability: WriteCapability, secret: SubspaceSecret) -> Option<Self> {
meadowcap::McIngredients::<
MCL,
MCC,
MPL,
NamespaceId,
NamespaceSignature,
SubspaceId,
SubspaceSignature,
SubspaceSecret,
>::new(capability.into(), secret)
.map(Into::into)
}
}