htsget-config 0.22.1

//! Crypt4GH key parsing.
//!

use crate::error::Error::{IoError, ParseError};
use crate::error::{Error, Result};
use crate::storage::c4gh::header::C4GHHeader;
use crate::storage::c4gh::local::C4GHLocal;
#[cfg(feature = "aws")]
use crate::storage::c4gh::secrets_manager::C4GHSecretsManager;
use crypt4gh::error::Crypt4GHError;
use futures_util::FutureExt;
use futures_util::future::{BoxFuture, Shared};
use schemars::JsonSchema;
use serde::Deserialize;
use std::pin::Pin;
use tokio::task::{JoinError, JoinHandle};

pub mod header;
pub mod local;
#[cfg(feature = "aws")]
pub mod secrets_manager;

/// Specifies the location of a Crypt4GH key.
#[derive(JsonSchema, Deserialize, Debug, Clone)]
#[serde(try_from = "C4GHKeySet", deny_unknown_fields)]
pub struct C4GHKeys {
  // Store a cloneable futures so that they can be resolved outside serde.
  #[schemars(with = "C4GHKeyLocation")]
  server_decryption_keys: Shared<BoxFuture<'static, Result<Vec<crypt4gh::Keys>>>>,
  #[schemars(with = "C4GHKeyLocation")]
  client_encryption_keys: Shared<BoxFuture<'static, Result<Vec<crypt4gh::Keys>>>>,
  client_key_from_header: Option<C4GHHeader>,
  #[schemars(skip)]
  encoded_server_public_key: Shared<BoxFuture<'static, Result<Vec<u8>>>>,
}

impl C4GHKeys {
  /// Get the inner values.
  pub async fn into_inner(
    self,
  ) -> Result<(
    Vec<crypt4gh::Keys>,
    Vec<crypt4gh::Keys>,
    Option<C4GHHeader>,
    Vec<u8>,
  )> {
    Ok((
      self.server_decryption_keys.await?,
      self.client_encryption_keys.await?,
      self.client_key_from_header,
      self.encoded_server_public_key.await?,
    ))
  }

  /// Construct the C4GH keys from a key pair.
  pub fn from_key_pair(private_key: Vec<u8>, recipient_public_key: Vec<u8>) -> Vec<crypt4gh::Keys> {
    vec![crypt4gh::Keys {
      method: 0,
      privkey: private_key,
      recipient_pubkey: recipient_public_key,
    }]
  }

  /// Construct from an existing join handle.
  pub fn from_join_handle(
    server_keys: JoinHandle<Result<Vec<crypt4gh::Keys>>>,
    client_keys: JoinHandle<Result<Vec<crypt4gh::Keys>>>,
    client_key_from_header: Option<C4GHHeader>,
    encoded_server_public_key: JoinHandle<Result<Vec<u8>>>,
  ) -> Self {
    Self {
      server_decryption_keys: server_keys.map(|value| value?).boxed().shared(),
      client_encryption_keys: client_keys.map(|value| value?).boxed().shared(),
      client_key_from_header,
      encoded_server_public_key: encoded_server_public_key
        .map(|value| value?)
        .boxed()
        .shared(),
    }
  }
}

impl From<JoinError> for Error {
  fn from(err: JoinError) -> Self {
    IoError(err.to_string())
  }
}

impl From<Crypt4GHError> for Error {
  fn from(err: Crypt4GHError) -> Self {
    ParseError(err.to_string())
  }
}

/// Specifies the location of a Crypt4GH key.
#[derive(JsonSchema, Deserialize, Debug, Clone)]
#[serde(tag = "kind", deny_unknown_fields)]
#[non_exhaustive]
pub enum C4GHKeyType {
  /// Obtain keys from a local file.
  #[serde(alias = "file", alias = "FILE")]
  File(C4GHLocal),
  /// Obtain keys from AWS secrets manager.
  #[cfg(feature = "aws")]
  #[serde(alias = "secretsmanager", alias = "SECRETSMANAGER")]
  SecretsManager(C4GHSecretsManager),
  /// Obtain keys from a header that comes with the request.
  #[serde(alias = "header", alias = "HEADER")]
  Header(C4GHHeader),
}

impl C4GHKeyType {
  /// Create a key type from a local file.
  pub fn new_file(file: C4GHLocal) -> Self {
    Self::File(file)
  }

  /// Create a key type from AWS secrets manager.
  #[cfg(feature = "aws")]
  pub fn new_secrets_manager(secrets_manager: C4GHSecretsManager) -> Self {
    Self::SecretsManager(secrets_manager)
  }

  /// Create a key type for obtaining keys from a header.
  pub fn new_header(header: C4GHHeader) -> Self {
    Self::Header(header)
  }
}

/// The specific location for a private and public key pair. If the private key is
/// unspecified then the public key is used for encryption, otherwise decryption is
/// used.
#[derive(JsonSchema, Deserialize, Debug, Clone)]
#[serde(deny_unknown_fields)]
pub struct C4GHKeyLocation {
  private: Option<C4GHKeyType>,
  public: C4GHKeyType,
}

impl C4GHKeyLocation {
  /// Create a new C4GH location.
  pub fn new(private: Option<C4GHKeyType>, public: C4GHKeyType) -> Self {
    Self { private, public }
  }
}

/// A keyset comprising the server's key pair and the client's public key, which will be used
/// to re-encrypt the header for the client.
#[derive(JsonSchema, Deserialize, Debug, Clone)]
#[serde(deny_unknown_fields)]
pub struct C4GHKeySet {
  server: C4GHKeyLocation,
  client: C4GHKeyLocation,
}

impl C4GHKeySet {
  /// Create a new key set.
  pub fn new(server: C4GHKeyLocation, client: C4GHKeyLocation) -> Self {
    Self { server, client }
  }
}

impl TryFrom<C4GHKeySet> for C4GHKeys {
  type Error = Error;

  fn try_from(location: C4GHKeySet) -> Result<Self> {
    let extract_private_key = |private_key| -> Result<Pin<Box<dyn Future<Output = _> + Send>>> {
      match private_key {
        Some(C4GHKeyType::File(file)) => Ok(Box::pin(async { file.into_private_key() })),
        #[cfg(feature = "aws")]
        Some(C4GHKeyType::SecretsManager(secrets_manager)) => {
          Ok(Box::pin(secrets_manager.into_private_key()))
        }
        Some(C4GHKeyType::Header(_)) => Err(ParseError(
          "using a header for private keys is unsupported".to_string(),
        )),
        _ => Err(ParseError("missing server private key".to_string())),
      }
    };

    type PublicKeyFuture = Pin<Box<dyn Future<Output = Result<Vec<u8>>> + Send>>;
    let extract_public_key = |public_key| -> (PublicKeyFuture, PublicKeyFuture, _) {
      match public_key {
        C4GHKeyType::File(file) => {
          let file_copy = file.clone();
          (
            Box::pin(async move { file_copy.public_key_encoded() }),
            Box::pin(async { file.into_public_key() }),
            None,
          )
        }
        #[cfg(feature = "aws")]
        C4GHKeyType::SecretsManager(secrets_manager) => {
          let secrets_manager_copy = secrets_manager.clone();
          (
            Box::pin(async move { secrets_manager_copy.public_key_encoded().await }),
            Box::pin(secrets_manager.into_public_key()),
            None,
          )
        }
        C4GHKeyType::Header(using_header) => (
          Box::pin(async { Ok(vec![]) }),
          Box::pin(async { Ok(vec![]) }),
          Some(using_header),
        ),
      }
    };

    let server_decryption_private = extract_private_key(location.server.private.clone())?;
    let server_encryption_private = extract_private_key(location.server.private)?;

    if location.client.private.is_some() {
      return Err(ParseError(
        "the client's private key should not be specified".to_string(),
      ));
    }

    let (encoded_public_key, server_public_key, server_key_from_header) =
      extract_public_key(location.server.public);
    if server_key_from_header.is_some() {
      return Err(ParseError(
        "the server's public key cannot be specified using a header".to_string(),
      ));
    }
    let (_, client_public_key, client_key_from_header) = extract_public_key(location.client.public);

    Ok(C4GHKeys::from_join_handle(
      tokio::spawn(async move {
        // Server decrypts using its own private key and public key.
        Ok(C4GHKeys::from_key_pair(
          server_decryption_private.await?,
          server_public_key.await?,
        ))
      }),
      tokio::spawn(async move {
        // Server encrypts using its own private key for the client who is the recipient.
        Ok(C4GHKeys::from_key_pair(
          server_encryption_private.await?,
          client_public_key.await?,
        ))
      }),
      client_key_from_header,
      tokio::spawn(encoded_public_key),
    ))
  }
}
#[cfg(test)]
pub(crate) mod tests {
  use crate::config::tests::test_config_from_file;
  use std::fs::copy;
  use std::path::{Path, PathBuf};
  use tempfile::TempDir;

  pub(crate) fn copy_c4gh_keys(path: &Path) -> (PathBuf, PathBuf, PathBuf) {
    let private_key = path.join("bob.sec");
    let server_public_key = path.join("bob.pub");
    let client_public_key = path.join("alice.pub");

    let parent = PathBuf::from(env!("CARGO_MANIFEST_DIR"))
      .parent()
      .unwrap()
      .to_path_buf();

    copy(parent.join("data/c4gh/keys/bob.sec"), &private_key).unwrap();
    copy(parent.join("data/c4gh/keys/bob.pub"), &server_public_key).unwrap();
    copy(parent.join("data/c4gh/keys/alice.pub"), &client_public_key).unwrap();

    (private_key, server_public_key, client_public_key)
  }

  #[should_panic]
  #[test]
  pub fn key_set_missing_server_public_key() {
    let tmp = TempDir::new().unwrap();
    let (private_key, _, client_public_key) = copy_c4gh_keys(tmp.path());

    test_config_from_file(
      &format!(
        r#"
        [[locations]]
        regex = "regex"

        [locations.backend]
        kind = "File"

        [locations.backend.keys]
        server.private.kind = "File"
        server.private.key = "{}"
        client.public.kind = "File"
        client.public.key = "{}"
        "#,
        private_key.to_string_lossy(),
        client_public_key.to_string_lossy()
      ),
      |_| {},
    );
  }

  #[should_panic]
  #[test]
  pub fn key_set_missing_client_public_key() {
    let tmp = TempDir::new().unwrap();
    let (private_key, server_public_key, _) = copy_c4gh_keys(tmp.path());

    test_config_from_file(
      &format!(
        r#"
        [[locations]]
        regex = "regex"

        [locations.backend]
        kind = "File"

        [locations.backend.keys]
        server.private.kind = "File"
        server.private.key = "{}"
        server.public.kind = "File"
        server.public.key = "{}"
        "#,
        private_key.to_string_lossy(),
        server_public_key.to_string_lossy(),
      ),
      |_| {},
    );
  }

  #[should_panic]
  #[test]
  pub fn key_set_specified_client_private_key() {
    let tmp = TempDir::new().unwrap();
    let (private_key, server_public_key, client_public_key) = copy_c4gh_keys(tmp.path());

    test_config_from_file(
      &format!(
        r#"
        [[locations]]
        regex = "regex"

        [locations.backend]
        kind = "File"

        [locations.backend.keys]
        server.private.kind = "File"
        server.private.key = "{}"
        server.public.kind = "File"
        server.public.key = "{}"
        client.public.kind = "File"
        client.public.key = "{}"
        client.private.kind = "File"
        client.private.key = "{}"
        "#,
        private_key.to_string_lossy(),
        server_public_key.to_string_lossy(),
        client_public_key.to_string_lossy(),
        private_key.to_string_lossy(),
      ),
      |_| {},
    );
  }

  #[should_panic]
  #[test]
  pub fn key_set_server_public_header() {
    let tmp = TempDir::new().unwrap();
    let (private_key, _, client_public_key) = copy_c4gh_keys(tmp.path());

    test_config_from_file(
      &format!(
        r#"
        [[locations]]
        regex = "regex"

        [locations.backend]
        kind = "File"

        [locations.backend.keys]
        server.private.kind = "File"
        server.private.key = "{}"
        server.public.kind = "Header"
        client.public.kind = "File"
        client.public.key = "{}"
        "#,
        private_key.to_string_lossy(),
        client_public_key.to_string_lossy()
      ),
      |_| {},
    );
  }

  #[should_panic]
  #[test]
  pub fn key_set_server_private_header() {
    let tmp = TempDir::new().unwrap();
    let (_, server_public_key, client_public_key) = copy_c4gh_keys(tmp.path());

    test_config_from_file(
      &format!(
        r#"
        [[locations]]
        regex = "regex"

        [locations.backend]
        kind = "File"

        [locations.backend.keys]
        server.private.kind = "Header"
        server.public.kind = "File"
        server.public.key = "{}"
        client.public.kind = "File"
        client.public.key = "{}"
        "#,
        server_public_key.to_string_lossy(),
        client_public_key.to_string_lossy()
      ),
      |_| {},
    );
  }
}