cosign/tuf: init

Signed-off-by: Jack Leightcap <[email protected]>
Co-authored-by: Andrew Pan <[email protected]>

Author: jleightcap

Cargo.toml

@@ -110,16 +110,20 @@ rsa = "0.9.2"
 scrypt = "0.11.0"
 serde = { version = "1.0.136", features = ["derive"] }
 serde_json = "1.0.79"
+serde_with = { version = "3.4.0", features = ["base64"] }
 sha2 = { version = "0.10.6", features = ["oid"] }
 signature = { version = "2.0" }
 thiserror = "1.0.30"
 tokio = { version = "1.17.0", features = ["rt"] }
 tough = { version = "0.14", features = ["http"], optional = true }
 tracing = "0.1.31"
 url = "2.2.2"
-x509-cert = { version = "0.2.2", features = ["pem", "std"] }
+x509-cert = { version = "0.2.2", features = ["builder", "pem", "std"] }
 crypto_secretbox = "0.1.1"
 zeroize = "1.5.7"
+rustls-webpki = { version = "0.102.0-alpha.4", features = ["alloc"] }
+rustls-pki-types = { version = "0.2.1", features = ["std"] }
+serde_repr = "0.1.16"
 
 [dev-dependencies]
 anyhow = { version = "1.0", features = ["backtrace"] }

examples/cosign/verify/main.rs

@@ -110,7 +110,7 @@ struct Cli {
 
 async fn run_app(
     cli: &Cli,
-    frd: &FulcioAndRekorData,
+    frd: &dyn sigstore::tuf::Repository,
 ) -> anyhow::Result<(Vec<SignatureLayer>, VerificationConstraintVec)> {
     // Note well: this a limitation deliberately introduced by this example.
     if cli.cert_email.is_some() && cli.cert_url.is_some() {
@@ -133,20 +133,13 @@ async fn run_app(
 
     let mut client_builder =
         sigstore::cosign::ClientBuilder::default().with_oci_client_config(oci_client_config);
-
-    if let Some(key) = frd.rekor_pub_key.as_ref() {
-        client_builder = client_builder.with_rekor_pub_key(key);
-    }
+    client_builder = client_builder.with_trust_repository(frd)?;
 
     let cert_chain: Option<Vec<sigstore::registry::Certificate>> = match cli.cert_chain.as_ref() {
         None => None,
         Some(cert_chain_path) => Some(parse_cert_bundle(cert_chain_path)?),
     };
 
-    if !frd.fulcio_certs.is_empty() {
-        client_builder = client_builder.with_fulcio_certs(&frd.fulcio_certs);
-    }
-
     if cli.enable_registry_caching {
         client_builder = client_builder.enable_registry_caching();
     }
@@ -194,7 +187,7 @@ async fn run_app(
     }
     if let Some(path_to_cert) = cli.cert.as_ref() {
         let cert = fs::read(path_to_cert).map_err(|e| anyhow!("Cannot read cert: {:?}", e))?;
-        let require_rekor_bundle = if frd.rekor_pub_key.is_some() {
+        let require_rekor_bundle = if !frd.rekor_keys()?.is_empty() {
             true
         } else {
             warn!("certificate based verification is weaker when Rekor integration is disabled");
@@ -235,31 +228,22 @@ async fn run_app(
     Ok((trusted_layers, verification_constraints))
 }
 
-#[derive(Default)]
-struct FulcioAndRekorData {
-    pub rekor_pub_key: Option<String>,
-    pub fulcio_certs: Vec<sigstore::registry::Certificate>,
-}
-
-async fn fulcio_and_rekor_data(cli: &Cli) -> anyhow::Result<FulcioAndRekorData> {
-    let mut data = FulcioAndRekorData::default();
-
+async fn fulcio_and_rekor_data(cli: &Cli) -> anyhow::Result<Box<dyn sigstore::tuf::Repository>> {
     if cli.use_sigstore_tuf_data {
         let repo: sigstore::errors::Result<SigstoreRepository> = spawn_blocking(|| {
             info!("Downloading data from Sigstore TUF repository");
-            sigstore::tuf::SigstoreRepository::fetch(None)
+            SigstoreRepository::new(None)?.prefetch()
         })
         .await
         .map_err(|e| anyhow!("Error spawning blocking task inside of tokio: {}", e))?;
 
-        let repo: SigstoreRepository = repo?;
-        data.fulcio_certs = repo.fulcio_certs().into();
-        data.rekor_pub_key = Some(repo.rekor_pub_key().to_string());
+        return Ok(Box::new(repo?));
     };
 
+    let mut data = sigstore::tuf::FakeRepository::default();
     if let Some(path) = cli.rekor_pub_key.as_ref() {
-        data.rekor_pub_key = Some(
-            fs::read_to_string(path)
+        data.rekor_key = Some(
+            fs::read(path)
                 .map_err(|e| anyhow!("Error reading rekor public key from disk: {}", e))?,
         );
     }
@@ -272,10 +256,12 @@ async fn fulcio_and_rekor_data(cli: &Cli) -> anyhow::Result<FulcioAndRekorData>
             encoding: sigstore::registry::CertificateEncoding::Pem,
             data: cert_data,
         };
-        data.fulcio_certs.push(certificate);
+        data.fulcio_certs
+            .get_or_insert(Vec::new())
+            .push(certificate.try_into()?);
     }
 
-    Ok(data)
+    Ok(Box::new(data))
 }
 
 #[tokio::main]
@@ -304,7 +290,7 @@ pub async fn main() {
             println!("Loop {}/{}", n + 1, cli.loops);
         }
 
-        match run_app(&cli, &frd).await {
+        match run_app(&cli, frd.as_ref()).await {
             Ok((trusted_layers, verification_constraints)) => {
                 let filter_result = sigstore::cosign::verify_constraints(
                     &trusted_layers,

src/cosign/client.rs

@@ -37,15 +37,15 @@ pub const CONFIG_DATA: &str = "{}";
 /// Cosign Client
 ///
 /// Instances of `Client` can be built via [`sigstore::cosign::ClientBuilder`](crate::cosign::ClientBuilder).
-pub struct Client {
+pub struct Client<'a> {
     pub(crate) registry_client: Box<dyn crate::registry::ClientCapabilities>,
     pub(crate) rekor_pub_key: Option<CosignVerificationKey>,
-    pub(crate) fulcio_cert_pool: Option<CertificatePool>,
+    pub(crate) fulcio_cert_pool: Option<CertificatePool<'a>>,
 }
 
 #[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 #[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
-impl CosignCapabilities for Client {
+impl CosignCapabilities for Client<'_> {
     async fn triangulate(
         &mut self,
         image: &OciReference,
@@ -140,7 +140,7 @@ impl CosignCapabilities for Client {
     }
 }
 
-impl Client {
+impl Client<'_> {
     /// Internal helper method used to fetch data from an OCI registry
     async fn fetch_manifest_and_layers(
         &mut self,
@@ -177,7 +177,7 @@ mod tests {
     use crate::crypto::SigningScheme;
     use crate::mock_client::test::MockOciClient;
 
-    fn build_test_client(mock_client: MockOciClient) -> Client {
+    fn build_test_client(mock_client: MockOciClient) -> Client<'static> {
         let rekor_pub_key =
             CosignVerificationKey::from_pem(REKOR_PUB_KEY.as_bytes(), &SigningScheme::default())
                 .expect("Cannot create CosignVerificationKey");

src/cosign/client_builder.rs

@@ -13,13 +13,15 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+use rustls_pki_types::CertificateDer;
 use tracing::info;
 
 use super::client::Client;
 use crate::crypto::SigningScheme;
 use crate::crypto::{certificate_pool::CertificatePool, CosignVerificationKey};
 use crate::errors::Result;
-use crate::registry::{Certificate, ClientConfig};
+use crate::registry::ClientConfig;
+use crate::tuf::Repository;
 
 /// A builder that generates Client objects.
 ///
@@ -34,7 +36,7 @@ use crate::registry::{Certificate, ClientConfig};
 /// ## Fulcio integration
 ///
 /// Fulcio integration can be enabled by specifying Fulcio's certificate.
-/// This can be provided via the [`ClientBuilder::with_fulcio_cert`] method.
+/// This can be provided via the [`ClientBuilder::with_fulcio_certs`] method.
 ///
 /// > Note well: the [`tuf`](crate::tuf) module provides helper structs and methods
 /// > to obtain this data from the official TUF repository of the Sigstore project.
@@ -50,63 +52,35 @@ use crate::registry::{Certificate, ClientConfig};
 ///
 /// Each cached entry will automatically expire after 60 seconds.
 #[derive(Default)]
-pub struct ClientBuilder {
+pub struct ClientBuilder<'a> {
     oci_client_config: ClientConfig,
-    rekor_pub_key: Option<String>,
-    fulcio_certs: Vec<Certificate>,
+    rekor_pub_key: Option<&'a [u8]>,
+    fulcio_certs: Vec<CertificateDer<'a>>,
+    // repo: Repository
     #[cfg(feature = "cached-client")]
     enable_registry_caching: bool,
 }
 
-impl ClientBuilder {
+impl<'a> ClientBuilder<'a> {
     /// Enable caching of data returned from remote OCI registries
     #[cfg(feature = "cached-client")]
     pub fn enable_registry_caching(mut self) -> Self {
         self.enable_registry_caching = true;
         self
     }
 
-    /// Specify the public key used by Rekor.
+    /// Optional - Configures the roots of trust.
     ///
-    /// The public key can be obtained by using the helper methods under the
-    /// [`tuf`](crate::tuf) module.
-    ///
-    /// `key` is a PEM encoded public key
-    ///
-    /// When provided, this enables Rekor's integration.
-    pub fn with_rekor_pub_key(mut self, key: &str) -> Self {
-        self.rekor_pub_key = Some(key.to_string());
-        self
-    }
-
-    /// Specify the certificate used by Fulcio. This method can be invoked
-    /// multiple times to add all the certificates that Fulcio used over the
-    /// time.
-    ///
-    /// `cert` is a PEM encoded certificate
-    ///
-    /// The certificates can be obtained by using the helper methods under the
-    /// [`tuf`](crate::tuf) module.
-    ///
-    /// When provided, this enables Fulcio's integration.
-    pub fn with_fulcio_cert(mut self, cert: &[u8]) -> Self {
-        let certificate = Certificate {
-            encoding: crate::registry::CertificateEncoding::Pem,
-            data: cert.to_owned(),
-        };
-        self.fulcio_certs.push(certificate);
-        self
-    }
+    /// Enables Fulcio and Rekor integration with the given trust repository.
+    /// See [crate::tuf::Repository] for more details on trust repositories.
+    pub fn with_trust_repository<R: Repository + ?Sized>(mut self, repo: &'a R) -> Result<Self> {
+        let rekor_keys = repo.rekor_keys()?;
+        if !rekor_keys.is_empty() {
+            self.rekor_pub_key = Some(rekor_keys[0]);
+        }
+        self.fulcio_certs = repo.fulcio_certs()?;
 
-    /// Specify the certificates used by Fulcio.
-    ///
-    /// The certificates can be obtained by using the helper methods under the
-    /// [`tuf`](crate::tuf) module.
-    ///
-    /// When provided, this enables Fulcio's integration.
-    pub fn with_fulcio_certs(mut self, certs: &[crate::registry::Certificate]) -> Self {
-        self.fulcio_certs = certs.to_vec();
-        self
+        Ok(self)
     }
 
     /// Optional - the configuration to be used by the OCI client.
@@ -118,14 +92,14 @@ impl ClientBuilder {
         self
     }
 
-    pub fn build(self) -> Result<Client> {
+    pub fn build(self) -> Result<Client<'a>> {
         let rekor_pub_key = match self.rekor_pub_key {
             None => {
                 info!("Rekor public key not provided. Rekor integration disabled");
                 None
             }
-            Some(data) => Some(CosignVerificationKey::from_pem(
-                data.as_bytes(),
+            Some(data) => Some(CosignVerificationKey::from_der(
+                data,
                 &SigningScheme::default(),
             )?),
         };
@@ -134,7 +108,7 @@ impl ClientBuilder {
             info!("No Fulcio cert has been provided. Fulcio integration disabled");
             None
         } else {
-            let cert_pool = CertificatePool::from_certificates(&self.fulcio_certs)?;
+            let cert_pool = CertificatePool::from_certificates(self.fulcio_certs, [])?;
             Some(cert_pool)
         };
 

src/cosign/mod.rs

@@ -282,6 +282,7 @@ where
 
 #[cfg(test)]
 mod tests {
+    use rustls_pki_types::CertificateDer;
     use serde_json::json;
     use std::collections::HashMap;
 
@@ -335,18 +336,15 @@ TNMea7Ix/stJ5TfcLLeABLE4BNJOsQ4vnBHJ
     #[cfg(feature = "test-registry")]
     const SIGNED_IMAGE: &str = "busybox:1.34";
 
-    pub(crate) fn get_fulcio_cert_pool() -> CertificatePool {
-        let certificates = vec![
-            crate::registry::Certificate {
-                encoding: crate::registry::CertificateEncoding::Pem,
-                data: FULCIO_CRT_1_PEM.as_bytes().to_vec(),
-            },
-            crate::registry::Certificate {
-                encoding: crate::registry::CertificateEncoding::Pem,
-                data: FULCIO_CRT_2_PEM.as_bytes().to_vec(),
-            },
-        ];
-        CertificatePool::from_certificates(&certificates).unwrap()
+    pub(crate) fn get_fulcio_cert_pool() -> CertificatePool<'static> {
+        fn pem_to_der<'a>(input: &'a str) -> CertificateDer<'a> {
+            let pem_cert = pem::parse(input).unwrap();
+            assert_eq!(pem_cert.tag(), "CERTIFICATE");
+            CertificateDer::from(pem_cert.into_contents())
+        }
+        let certificates = vec![pem_to_der(FULCIO_CRT_1_PEM), pem_to_der(FULCIO_CRT_2_PEM)];
+
+        CertificatePool::from_certificates(certificates, []).unwrap()
     }
 
     pub(crate) fn get_rekor_public_key() -> CosignVerificationKey {
@@ -645,7 +643,7 @@ TNMea7Ix/stJ5TfcLLeABLE4BNJOsQ4vnBHJ
     }
 
     #[cfg(feature = "test-registry")]
-    async fn prepare_image_to_be_signed(client: &mut Client, image_ref: &OciReference) {
+    async fn prepare_image_to_be_signed(client: &mut Client<'_>, image_ref: &OciReference) {
         let data = client
             .registry_client
             .pull(

src/cosign/signature_layers.rs

@@ -438,7 +438,12 @@ impl CertificateSignature {
         let integrated_time = trusted_bundle.payload.integrated_time;
 
         // ensure the certificate has been issued by Fulcio
-        fulcio_cert_pool.verify_pem_cert(cert_pem)?;
+        fulcio_cert_pool.verify_pem_cert(
+            cert_pem,
+            Some(rustls_pki_types::UnixTime::since_unix_epoch(
+                cert.tbs_certificate.validity.not_before.to_unix_duration(),
+            )),
+        )?;
 
         crypto::certificate::is_trusted(&cert, integrated_time)?;
 
@@ -899,8 +904,10 @@ JsB89BPhZYch0U0hKANx5TY+ncrm0s8bfJxxHoenAEFhwhuXeb4PqIrtoQ==
 
         let issued_cert_pem = issued_cert.cert.to_pem()?;
 
-        let certs = vec![crate::registry::Certificate::try_from(ca_data.cert).unwrap()];
-        let cert_pool = CertificatePool::from_certificates(&certs).unwrap();
+        let certs = vec![crate::registry::Certificate::try_from(ca_data.cert)
+            .unwrap()
+            .try_into()?];
+        let cert_pool = CertificatePool::from_certificates(certs, []).unwrap();
 
         let integrated_time = Utc::now().checked_sub_signed(Duration::minutes(1)).unwrap();
         let bundle = Bundle {
@@ -946,8 +953,10 @@ JsB89BPhZYch0U0hKANx5TY+ncrm0s8bfJxxHoenAEFhwhuXeb4PqIrtoQ==
 
         let issued_cert_pem = issued_cert.cert.to_pem()?;
 
-        let certs = vec![crate::registry::Certificate::try_from(ca_data.cert).unwrap()];
-        let cert_pool = CertificatePool::from_certificates(&certs).unwrap();
+        let certs = vec![crate::registry::Certificate::try_from(ca_data.cert)
+            .unwrap()
+            .try_into()?];
+        let cert_pool = CertificatePool::from_certificates(certs, []).unwrap();
 
         let integrated_time = Utc::now().checked_sub_signed(Duration::minutes(1)).unwrap();
         let bundle = Bundle {
@@ -992,8 +1001,10 @@ JsB89BPhZYch0U0hKANx5TY+ncrm0s8bfJxxHoenAEFhwhuXeb4PqIrtoQ==
 
         let issued_cert_pem = issued_cert.cert.to_pem()?;
 
-        let certs = vec![crate::registry::Certificate::try_from(ca_data.cert).unwrap()];
-        let cert_pool = CertificatePool::from_certificates(&certs).unwrap();
+        let certs = vec![crate::registry::Certificate::try_from(ca_data.cert)
+            .unwrap()
+            .try_into()?];
+        let cert_pool = CertificatePool::from_certificates(certs, []).unwrap();
 
         let integrated_time = Utc::now().checked_sub_signed(Duration::minutes(1)).unwrap();
         let bundle = Bundle {