cms: adds support for AsyncSigner

cms/Cargo.toml

@@ -22,6 +22,7 @@ const-oid = { version = "0.10.0-rc.0", features = ["db"] }
 
 # optional dependencies
 aes = { version = "=0.9.0-pre.1", optional = true }
+async-signature = { version = "=0.6.0-pre.4", features = ["digest", "rand_core"], optional = true }
 cbc = { version = "=0.2.0-pre.1", optional = true }
 cipher = { version = "=0.5.0-pre.6", features = ["alloc", "block-padding", "rand_core"], optional = true }
 rsa = { version = "=0.10.0-pre.2", optional = true }
@@ -40,11 +41,12 @@ rand = "0.8.5"
 rsa = { version = "=0.10.0-pre.2", features = ["sha2"] }
 ecdsa = { version = "=0.17.0-pre.9", features = ["digest", "pem"] }
 p256 = "=0.14.0-pre.2"
+tokio = { version = "1.40.0", features = ["macros", "rt"] }
 
 [features]
 alloc = ["der/alloc"]
 std = ["der/std", "spki/std"]
-builder = ["aes", "cbc", "cipher", "rsa", "sha1", "sha2", "sha3", "signature", "std", "spki/alloc", "x509-cert/builder", "zeroize"]
+builder = ["aes", "async-signature", "cbc", "cipher", "rsa", "sha1", "sha2", "sha3", "signature", "std", "spki/alloc", "x509-cert/builder", "zeroize"]
 pem = ["alloc", "der/pem"]
 
 [package.metadata.docs.rs]

cms/src/builder.rs

@@ -19,6 +19,7 @@ use alloc::borrow::ToOwned;
 use alloc::boxed::Box;
 use alloc::string::String;
 use alloc::vec::Vec;
+use async_signature::{AsyncRandomizedSigner, AsyncSigner};
 use cipher::{
     block_padding::Pkcs7,
     rand_core::{self, CryptoRng, CryptoRngCore, RngCore},
@@ -43,7 +44,7 @@ use spki::{
 use std::time::SystemTime;
 use std::vec;
 use x509_cert::attr::{Attribute, AttributeValue, Attributes};
-use x509_cert::builder::{self, Builder};
+use x509_cert::builder::{self, AsyncBuilder, Builder};
 use zeroize::Zeroize;
 
 /// Error type
@@ -404,6 +405,51 @@ impl<'s> SignedDataBuilder<'s> {
         Ok(self)
     }
 
+    /// Add a signer info. The signature will be calculated. Note that the encapsulated content
+    /// must not be changed after the first signer info was added.
+    pub async fn add_signer_info_async<S, Signature>(
+        &mut self,
+        signer_info_builder: SignerInfoBuilder<'_>,
+        signer: &S,
+    ) -> Result<&mut Self>
+    where
+        S: Keypair + DynSignatureAlgorithmIdentifier,
+        S: AsyncSigner<Signature>,
+        S::VerifyingKey: EncodePublicKey,
+        Signature: SignatureBitStringEncoding,
+    {
+        let signer_info = signer_info_builder
+            .build_async::<S, Signature>(signer)
+            .await
+            .map_err(|_| der::Error::from(ErrorKind::Failed))?;
+        self.signer_infos.push(signer_info);
+
+        Ok(self)
+    }
+
+    /// Add a signer info. The signature will be calculated. Note that the encapsulated content
+    /// must not be changed after the first signer info was added.
+    pub async fn add_signer_info_with_rng_async<S, Signature>(
+        &mut self,
+        signer_info_builder: SignerInfoBuilder<'_>,
+        signer: &S,
+        rng: &mut impl CryptoRngCore,
+    ) -> Result<&mut Self>
+    where
+        S: Keypair + DynSignatureAlgorithmIdentifier,
+        S: AsyncRandomizedSigner<Signature>,
+        S::VerifyingKey: EncodePublicKey,
+        Signature: SignatureBitStringEncoding,
+    {
+        let signer_info = signer_info_builder
+            .build_with_rng_async::<S, Signature>(signer, rng)
+            .await
+            .map_err(|_| der::Error::from(ErrorKind::Failed))?;
+        self.signer_infos.push(signer_info);
+
+        Ok(self)
+    }
+
     /// This method returns a `ContentInfo` of type `signedData`.
     pub fn build(&mut self) -> Result<ContentInfo> {
         let digest_algorithms =

cms/tests/builder.rs

@@ -569,3 +569,75 @@ fn test_create_signing_attribute() {
         "Invalid tag number in signing time attribute value"
     );
 }
+
+#[tokio::test]
+async fn async_builder() {
+    // Make some content
+    let content = EncapsulatedContentInfo {
+        econtent_type: const_oid::db::rfc5911::ID_DATA,
+        econtent: Some(
+            Any::new(
+                Tag::OctetString,
+                OctetString::new(vec![48]).unwrap().to_der().unwrap(),
+            )
+            .unwrap(),
+        ),
+    };
+    // Create multiple signer infos
+    let signer_1 = rsa_pkcs1v15_signer();
+    let digest_algorithm = AlgorithmIdentifierOwned {
+        oid: const_oid::db::rfc5912::ID_SHA_256,
+        parameters: None,
+    };
+    let external_message_digest = None;
+    let signer_info_builder_1 = SignerInfoBuilder::new(
+        signer_identifier(1),
+        digest_algorithm.clone(),
+        &content,
+        external_message_digest,
+    )
+    .expect("Could not create RSA SignerInfoBuilder");
+
+    let signer_3 = rsa_pss_signer();
+    let digest_algorithm = AlgorithmIdentifierOwned {
+        oid: const_oid::db::rfc5912::ID_SHA_256,
+        parameters: None,
+    };
+    let external_message_digest = None;
+    let signer_info_builder_3 = SignerInfoBuilder::new(
+        signer_identifier(3),
+        digest_algorithm.clone(),
+        &content,
+        external_message_digest,
+    )
+    .expect("Could not create RSA SignerInfoBuilder");
+
+    let mut builder = SignedDataBuilder::new(&content);
+
+    let signed_data_pkcs7 = builder
+        .add_digest_algorithm(digest_algorithm)
+        .expect("could not add a digest algorithm")
+        .add_signer_info_async::<pkcs1v15::SigningKey<Sha256>, rsa::pkcs1v15::Signature>(
+            signer_info_builder_1,
+            &signer_1,
+        )
+        .await
+        .expect("error adding PKCS1v15 RSA signer info")
+        .add_signer_info_with_rng_async::<pss::SigningKey<Sha256>, pss::Signature>(
+            signer_info_builder_3,
+            &signer_3,
+            &mut OsRng,
+        )
+        .await
+        .expect("error adding PKCS1v15 RSA signer info")
+        .build()
+        .expect("building signed data failed");
+    let signed_data_pkcs7_der = signed_data_pkcs7
+        .to_der()
+        .expect("conversion of signed data to DER failed.");
+    println!(
+        "{}",
+        pem_rfc7468::encode_string("PKCS7", LineEnding::LF, &signed_data_pkcs7_der)
+            .expect("PEM encoding of signed data DER failed")
+    );
+}