Added asymmetric encrypt and decrypt

Signed-off-by: Samuel Bailey <samuel.bailey@arm.com>

Cargo.toml

@@ -25,7 +25,7 @@ prost = "0.6.1"
 arbitrary = { version = "0.4.4", features = ["derive"] }
 uuid = "0.7.4"
 log = "0.4.8"
-psa-crypto = { version = "0.2.0", default-features = false }
+psa-crypto = { version = "0.2.2", default-features = false }
 zeroize = { version = "1.1.0", features = ["zeroize_derive"] }
 secrecy = { version = "0.6.0", features = ["serde"] }
 derivative = "2.1.1"

src/operations/mod.rs

@@ -16,6 +16,8 @@ pub mod psa_export_public_key;
 pub mod psa_destroy_key;
 pub mod psa_sign_hash;
 pub mod psa_verify_hash;
+pub mod psa_asymmetric_encrypt;
+pub mod psa_asymmetric_decrypt;
 pub mod list_opcodes;
 pub mod list_providers;
 
@@ -46,6 +48,10 @@ pub enum NativeOperation {
     PsaSignHash(psa_sign_hash::Operation),
     /// PsaVerifyHash operation
     PsaVerifyHash(psa_verify_hash::Operation),
+    /// PsaAsymmetricEncrypt operation
+    PsaAsymmetricEncrypt(psa_asymmetric_encrypt::Operation),
+    /// PsaAsymmetricDecrypt operation
+    PsaAsymmetricDecrypt(psa_asymmetric_decrypt::Operation),
 }
 
 impl NativeOperation {
@@ -61,6 +67,8 @@ impl NativeOperation {
             NativeOperation::PsaExportPublicKey(_) => Opcode::PsaExportPublicKey,
             NativeOperation::ListOpcodes(_) => Opcode::ListOpcodes,
             NativeOperation::ListProviders(_) => Opcode::ListProviders,
+            NativeOperation::PsaAsymmetricEncrypt(_) => Opcode::PsaAsymmetricEncrypt,
+            NativeOperation::PsaAsymmetricDecrypt(_) => Opcode::PsaAsymmetricDecrypt,
         }
     }
 }
@@ -87,6 +95,10 @@ pub enum NativeResult {
     PsaSignHash(psa_sign_hash::Result),
     /// PsaVerifyHash result
     PsaVerifyHash(psa_verify_hash::Result),
+    /// PsaAsymmetricEncrypt result
+    PsaAsymmetricEncrypt(psa_asymmetric_encrypt::Result),
+    /// PsaAsymmetricDecrypt result
+    PsaAsymmetricDecrypt(psa_asymmetric_decrypt::Result),
 }
 
 impl NativeResult {
@@ -102,6 +114,8 @@ impl NativeResult {
             NativeResult::PsaExportPublicKey(_) => Opcode::PsaExportPublicKey,
             NativeResult::ListOpcodes(_) => Opcode::ListOpcodes,
             NativeResult::ListProviders(_) => Opcode::ListProviders,
+            NativeResult::PsaAsymmetricEncrypt(_) => Opcode::PsaAsymmetricEncrypt,
+            NativeResult::PsaAsymmetricDecrypt(_) => Opcode::PsaAsymmetricDecrypt,
         }
     }
 }

src/operations/psa_asymmetric_decrypt.rs

@@ -0,0 +1,168 @@
+// Copyright 2020 Contributors to the Parsec project.
+// SPDX-License-Identifier: Apache-2.0
+//! # PsaAsymmetricDecrypt operation
+//!
+//! Decrypt a short message with a public key.
+
+use super::psa_key_attributes::Attributes;
+use crate::operations::psa_algorithm::AsymmetricEncryption;
+use crate::requests::ResponseStatus;
+#[cfg(feature = "fuzz")]
+use arbitrary::Arbitrary;
+use derivative::Derivative;
+
+/// Native object for asymmetric decryption operations.
+#[derive(Derivative)]
+#[derivative(Debug)]
+pub struct Operation {
+    /// Defines which key should be used for the signing operation.
+    pub key_name: String,
+    /// An asymmetric encryption algorithm to be used for decryption, that is compatible with the type of key.
+    pub alg: AsymmetricEncryption,
+    /// The short encrypted message to be decrypted.
+    #[derivative(Debug = "ignore")]
+    pub ciphertext: zeroize::Zeroizing<Vec<u8>>,
+    /// Salt to use during decryption, if supported by the algorithm.
+    #[derivative(Debug = "ignore")]
+    pub salt: Option<zeroize::Zeroizing<Vec<u8>>>,
+}
+
+impl Operation {
+    /// Validate the contents of the operation against the attributes of the key it targets
+    ///
+    /// This method checks that:
+    /// * the key policy allows decrypting messages
+    /// * the key policy allows the decryption algorithm requested in the operation
+    /// * the key type is compatible with the requested algorithm
+    /// * if the algorithm is RsaPkcs1v15Crypt, it has no salt (it is not compatible with salt)
+    /// * the message to decrypt is valid (not length 0)
+    pub fn validate(&self, key_attributes: Attributes) -> crate::requests::Result<()> {
+        key_attributes.can_decrypt_message()?;
+        key_attributes.permits_alg(self.alg.into())?;
+        key_attributes.compatible_with_alg(self.alg.into())?;
+        if (self.alg == AsymmetricEncryption::RsaPkcs1v15Crypt && self.salt != None)
+            || self.ciphertext.is_empty()
+        {
+            return Err(ResponseStatus::PsaErrorInvalidArgument);
+        }
+        Ok(())
+    }
+}
+
+/// Native object for asymmetric decrypt result.
+// Debug derived as NativeResult enum requires it, even though nothing inside this Result is debuggable
+// as `plaintext` is sensitive.
+#[derive(Derivative)]
+#[derivative(Debug)]
+pub struct Result {
+    /// Decrypted message
+    #[derivative(Debug = "ignore")]
+    pub plaintext: zeroize::Zeroizing<Vec<u8>>,
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::operations::psa_algorithm::{AsymmetricEncryption, Hash};
+    use crate::operations::psa_key_attributes::{Lifetime, Policy, Type, UsageFlags};
+    use zeroize::Zeroizing;
+
+    fn get_attrs() -> Attributes {
+        Attributes {
+            lifetime: Lifetime::Persistent,
+            key_type: Type::RsaKeyPair,
+            bits: 256,
+            policy: Policy {
+                usage_flags: UsageFlags {
+                    export: false,
+                    copy: false,
+                    cache: false,
+                    encrypt: false,
+                    decrypt: true,
+                    sign_message: false,
+                    verify_message: false,
+                    sign_hash: false,
+                    verify_hash: false,
+                    derive: false,
+                },
+                permitted_algorithms: AsymmetricEncryption::RsaPkcs1v15Crypt.into(),
+            },
+        }
+    }
+
+    #[test]
+    fn validate_success() {
+        (Operation {
+            key_name: String::from("some key"),
+            alg: AsymmetricEncryption::RsaPkcs1v15Crypt,
+            ciphertext: Zeroizing::new(vec![0xff, 32]),
+            salt: None,
+        })
+        .validate(get_attrs())
+        .unwrap();
+    }
+
+    #[test]
+    fn cannot_decrypt() {
+        let mut attrs = get_attrs();
+        attrs.policy.usage_flags.decrypt = false;
+        assert_eq!(
+            (Operation {
+                key_name: String::from("some key"),
+                alg: AsymmetricEncryption::RsaPkcs1v15Crypt,
+                ciphertext: Zeroizing::new(vec![0xff, 32]),
+                salt: None,
+            })
+            .validate(attrs)
+            .unwrap_err(),
+            ResponseStatus::PsaErrorNotPermitted
+        );
+    }
+
+    #[test]
+    fn wrong_algorithm() {
+        assert_eq!(
+            (Operation {
+                key_name: String::from("some key"),
+                alg: AsymmetricEncryption::RsaOaep {
+                    hash_alg: Hash::Sha256,
+                },
+                ciphertext: Zeroizing::new(vec![0xff, 32]),
+                salt: None,
+            })
+            .validate(get_attrs())
+            .unwrap_err(),
+            ResponseStatus::PsaErrorNotPermitted
+        );
+    }
+
+    #[test]
+    fn invalid_ciphertext() {
+        assert_eq!(
+            (Operation {
+                key_name: String::from("some key"),
+                alg: AsymmetricEncryption::RsaPkcs1v15Crypt,
+                ciphertext: Zeroizing::new(vec![]),
+                salt: None,
+            })
+            .validate(get_attrs())
+            .unwrap_err(),
+            ResponseStatus::PsaErrorInvalidArgument
+        );
+    }
+
+    #[test]
+    fn salt_with_rsapkcs1v15crypt() {
+        assert_eq!(
+            (Operation {
+                key_name: String::from("some key"),
+                alg: AsymmetricEncryption::RsaPkcs1v15Crypt,
+                ciphertext: Zeroizing::new(vec![0xff, 32]),
+                salt: Some(zeroize::Zeroizing::new(vec![0xff, 32])),
+            })
+            .validate(get_attrs())
+            .unwrap_err(),
+            ResponseStatus::PsaErrorInvalidArgument
+        );
+    }
+}

src/operations/psa_asymmetric_encrypt.rs

@@ -0,0 +1,163 @@
+// Copyright 2020 Contributors to the Parsec project.
+// SPDX-License-Identifier: Apache-2.0
+//! # PsaAsymmetricEncrypt operation
+//!
+//! Encrypt a short message with a public key.
+
+use super::psa_key_attributes::Attributes;
+use crate::operations::psa_algorithm::AsymmetricEncryption;
+use crate::requests::ResponseStatus;
+use derivative::Derivative;
+
+/// Native object for asymmetric encryption operations.
+#[derive(Derivative)]
+#[derivative(Debug)]
+pub struct Operation {
+    /// Defines which key should be used for the encryption operation.
+    pub key_name: String,
+    /// An asymmetric encryption algorithm that is compatible with the key type
+    pub alg: AsymmetricEncryption,
+    /// The short message to be encrypted.
+    #[derivative(Debug = "ignore")]
+    pub plaintext: zeroize::Zeroizing<Vec<u8>>,
+    /// Salt to use during encryption, if supported by the algorithm.
+    #[derivative(Debug = "ignore")]
+    pub salt: Option<zeroize::Zeroizing<Vec<u8>>>,
+}
+
+impl Operation {
+    /// Validate the contents of the operation against the attributes of the key it targets
+    ///
+    /// This method checks that:
+    /// * the key policy allows encrypting messages
+    /// * the key policy allows the encryption algorithm requested in the operation
+    /// * the key type is compatible with the requested algorithm
+    /// * if the algorithm is RsaPkcs1v15Crypt, it has no salt (it is not compatible with salt)
+    /// * the message to encrypt is valid (not length 0)
+    pub fn validate(&self, key_attributes: Attributes) -> crate::requests::Result<()> {
+        key_attributes.can_encrypt_message()?;
+        key_attributes.permits_alg(self.alg.into())?;
+        key_attributes.compatible_with_alg(self.alg.into())?;
+        if (self.alg == AsymmetricEncryption::RsaPkcs1v15Crypt && self.salt != None)
+            || self.plaintext.is_empty()
+        {
+            return Err(ResponseStatus::PsaErrorInvalidArgument);
+        }
+        Ok(())
+    }
+}
+
+/// Native object for asymmetric encrypt result.
+#[derive(Derivative)]
+#[derivative(Debug)]
+pub struct Result {
+    /// The `ciphertext` field contains the encrypted short message.
+    #[derivative(Debug = "ignore")]
+    pub ciphertext: zeroize::Zeroizing<Vec<u8>>,
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::operations::psa_algorithm::{AsymmetricEncryption, Hash};
+    use crate::operations::psa_key_attributes::{Lifetime, Policy, Type, UsageFlags};
+
+    fn get_attrs() -> Attributes {
+        Attributes {
+            lifetime: Lifetime::Persistent,
+            key_type: Type::RsaKeyPair,
+            bits: 256,
+            policy: Policy {
+                usage_flags: UsageFlags {
+                    export: false,
+                    copy: false,
+                    cache: false,
+                    encrypt: true,
+                    decrypt: false,
+                    sign_message: false,
+                    verify_message: false,
+                    sign_hash: false,
+                    verify_hash: false,
+                    derive: false,
+                },
+                permitted_algorithms: AsymmetricEncryption::RsaPkcs1v15Crypt.into(),
+            },
+        }
+    }
+
+    #[test]
+    fn validate_success() {
+        (Operation {
+            key_name: String::from("some key"),
+            alg: AsymmetricEncryption::RsaPkcs1v15Crypt,
+            plaintext: vec![0xff, 32].into(),
+            salt: None,
+        })
+        .validate(get_attrs())
+        .unwrap();
+    }
+
+    #[test]
+    fn cannot_encrypt() {
+        let mut attrs = get_attrs();
+        attrs.policy.usage_flags.encrypt = false;
+        assert_eq!(
+            (Operation {
+                key_name: String::from("some key"),
+                alg: AsymmetricEncryption::RsaPkcs1v15Crypt,
+                plaintext: vec![0xff, 32].into(),
+                salt: None,
+            })
+            .validate(attrs)
+            .unwrap_err(),
+            ResponseStatus::PsaErrorNotPermitted
+        );
+    }
+
+    #[test]
+    fn wrong_algorithm() {
+        assert_eq!(
+            (Operation {
+                key_name: String::from("some key"),
+                alg: AsymmetricEncryption::RsaOaep {
+                    hash_alg: Hash::Sha256,
+                },
+                plaintext: vec![0xff, 32].into(),
+                salt: None,
+            })
+            .validate(get_attrs())
+            .unwrap_err(),
+            ResponseStatus::PsaErrorNotPermitted
+        );
+    }
+
+    #[test]
+    fn invalid_plaintext() {
+        assert_eq!(
+            (Operation {
+                key_name: String::from("some key"),
+                alg: AsymmetricEncryption::RsaPkcs1v15Crypt,
+                plaintext: vec![].into(),
+                salt: None,
+            })
+            .validate(get_attrs())
+            .unwrap_err(),
+            ResponseStatus::PsaErrorInvalidArgument
+        );
+    }
+
+    #[test]
+    fn salt_with_rsapkcs1v15crypt() {
+        assert_eq!(
+            (Operation {
+                key_name: String::from("some key"),
+                alg: AsymmetricEncryption::RsaPkcs1v15Crypt,
+                plaintext: vec![0xff, 32].into(),
+                salt: Some(zeroize::Zeroizing::new(vec![0xff, 32])),
+            })
+            .validate(get_attrs())
+            .unwrap_err(),
+            ResponseStatus::PsaErrorInvalidArgument
+        );
+    }
+}