Interface updates

Signed-off-by: AssemblyJohn <[email protected]>

include/evse_security/crypto/interface/crypto_supplier.hpp

@@ -72,7 +72,8 @@ class AbstractCryptoSupplier {
                                       const std::vector<std::uint8_t>& data);
 
     /// @brief Generates a certificate signing request with the provided parameters
-    static bool x509_generate_csr(const CertificateSigningRequestInfo& generation_info, std::string& out_csr);
+    static CertificateSignRequestResult x509_generate_csr(const CertificateSigningRequestInfo& generation_info,
+                                                          std::string& out_csr);
 
 public: // Digesting/decoding utils
     static bool digest_file_sha256(const fs::path& path, std::vector<std::uint8_t>& out_digest);

include/evse_security/crypto/interface/crypto_types.hpp

@@ -25,6 +25,16 @@ enum class KeyValidationResult {
     Unknown,        // Unknown error, not related to provider validation
 };
 
+enum class CertificateSignRequestResult {
+    Valid,
+    KeyGenerationError, // Error when generating the key, maybe invalid key type
+    VersioningError,    // The version could not be set
+    PubkeyError,        // The public key could not be attached
+    ExtensionsError,    // The extensions could not be appended
+    SigningError,       // The CSR could not be signed, maybe key or signing algo invalid
+    Unknown,            // Any other error
+};
+
 struct KeyGenerationInfo {
     CryptoKeyType key_type;
 
@@ -77,4 +87,8 @@ using KeyHandle_ptr = std::unique_ptr<KeyHandle>;
 // Transforms a duration of days into seconds
 using days_to_seconds = std::chrono::duration<std::int64_t, std::ratio<86400>>;
 
+namespace conversions {
+std::string get_certificate_sign_request_result_to_string(CertificateSignRequestResult e);
+}
+
 } // namespace evse_security

include/evse_security/crypto/openssl/openssl_supplier.hpp

@@ -41,7 +41,8 @@ class OpenSSLSupplier : public AbstractCryptoSupplier {
     static bool x509_verify_signature(X509Handle* handle, const std::vector<std::uint8_t>& signature,
                                       const std::vector<std::uint8_t>& data);
 
-    static bool x509_generate_csr(const CertificateSigningRequestInfo& csr_info, std::string& out_csr);
+    static CertificateSignRequestResult x509_generate_csr(const CertificateSigningRequestInfo& csr_info,
+                                                          std::string& out_csr);
 
 public:
     static bool digest_file_sha256(const fs::path& path, std::vector<std::uint8_t>& out_digest);

include/evse_security/evse_security.hpp

@@ -165,20 +165,23 @@ class EvseSecurity {
     /// @param organization
     /// @param common
     /// @param use_tpm  If the TPM should be used for the CSR request
-    /// @return the PEM formatted certificate signing request
-    std::string generate_certificate_signing_request(LeafCertificateType certificate_type, const std::string& country,
-                                                     const std::string& organization, const std::string& common,
-                                                     bool use_tpm);
+    /// @return the status and an optional PEM formatted certificate signing request string
+    GetCertificateSignRequestResult generate_certificate_signing_request(LeafCertificateType certificate_type,
+                                                                         const std::string& country,
+                                                                         const std::string& organization,
+                                                                         const std::string& common, bool use_tpm);
 
     /// @brief Generates a certificate signing request for the given \p certificate_type , \p country , \p organization
     /// and \p common without using the TPM
     /// @param certificate_type
     /// @param country
     /// @param organization
     /// @param common
-    /// @return the PEM formatted certificate signing request
-    std::string generate_certificate_signing_request(LeafCertificateType certificate_type, const std::string& country,
-                                                     const std::string& organization, const std::string& common);
+    /// @return the status and an optional PEM formatted certificate signing request string
+    GetCertificateSignRequestResult generate_certificate_signing_request(LeafCertificateType certificate_type,
+                                                                         const std::string& country,
+                                                                         const std::string& organization,
+                                                                         const std::string& common);
 
     /// @brief Searches the filesystem on the specified directories for the given \p certificate_type and retrieves the
     /// most recent certificate that is already valid and the respective key.  If no certificate is present or no key is
@@ -203,6 +206,9 @@ class EvseSecurity {
     /// @return CA certificate file
     std::string get_verify_file(CaCertificateType certificate_type);
 
+    /// @brief An extension of 'get_verify_file' with error handling included
+    GetCertificateInfoResult get_ca_certificate_info(CaCertificateType certificate_type);
+
     /// @brief Gets the expiry day count for the leaf certificate of the given \p certificate_type
     /// @param certificate_type
     /// @return day count until the leaf certificate expires
@@ -248,9 +254,14 @@ class EvseSecurity {
                                                             LeafCertificateType certificate_type);
     GetCertificateInfoResult get_leaf_certificate_info_internal(LeafCertificateType certificate_type,
                                                                 EncodingFormat encoding, bool include_ocsp = false);
+    GetCertificateInfoResult get_ca_certificate_info_internal(CaCertificateType certificate_type);
     std::optional<fs::path> retrieve_ocsp_cache_internal(const CertificateHashData& certificate_hash_data);
     bool is_ca_certificate_installed_internal(CaCertificateType certificate_type);
 
+    GetCertificateSignRequestResult
+    generate_certificate_signing_request_internal(LeafCertificateType certificate_type,
+                                                  const CertificateSigningRequestInfo& info);
+
     /// @brief Determines if the total filesize of certificates is > than the max_filesystem_usage bytes
     bool is_filesystem_full();
 

include/evse_security/evse_types.hpp

@@ -90,6 +90,13 @@ enum class GetCertificateInfoStatus {
     PrivateKeyNotFound,
 };
 
+enum class GetCertificateSignRequestStatus {
+    Accepted,
+    InvalidRequestedType, ///< Requested a CSR for non CSMS/V2G leafs
+    KeyGenError,          ///< The key could not be generated with the requested/default parameters
+    GenerationError,      ///< Any other error when creating the CSR
+};
+
 // types of evse_security
 
 struct CertificateHashData {
@@ -148,6 +155,12 @@ struct GetCertificateInfoResult {
     GetCertificateInfoStatus status;
     std::optional<CertificateInfo> info;
 };
+
+struct GetCertificateSignRequestResult {
+    GetCertificateSignRequestStatus status;
+    std::optional<std::string> csr;
+};
+
 namespace conversions {
 std::string encoding_format_to_string(EncodingFormat e);
 std::string ca_certificate_type_to_string(CaCertificateType e);

lib/evse_security/CMakeLists.txt

@@ -14,6 +14,7 @@ target_sources(evse_security
         utils/evse_filesystem.cpp
 
         crypto/interface/crypto_supplier.cpp
+        crypto/interface/crypto_types.cpp
         crypto/openssl/openssl_supplier.cpp
         crypto/openssl/openssl_tpm.cpp
 )

lib/evse_security/crypto/interface/crypto_supplier.cpp

@@ -91,8 +91,9 @@ bool AbstractCryptoSupplier::x509_verify_signature(X509Handle* handle, const std
     default_crypto_supplier_usage_error() return false;
 }
 
-bool AbstractCryptoSupplier::x509_generate_csr(const CertificateSigningRequestInfo& csr_info, std::string& out_csr) {
-    default_crypto_supplier_usage_error() return false;
+CertificateSignRequestResult AbstractCryptoSupplier::x509_generate_csr(const CertificateSigningRequestInfo& csr_info,
+                                                                       std::string& out_csr) {
+    default_crypto_supplier_usage_error() return CertificateSignRequestResult::Unknown;
 }
 
 bool AbstractCryptoSupplier::digest_file_sha256(const fs::path& path, std::vector<std::uint8_t>& out_digest) {

lib/evse_security/crypto/interface/crypto_types.cpp

@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright Pionix GmbH and Contributors to EVerest
+
+#include <evse_security/crypto/interface/crypto_types.hpp>
+
+namespace evse_security {
+
+namespace conversions {
+
+std::string get_certificate_sign_request_result_to_string(CertificateSignRequestResult e) {
+
+    switch (e) {
+    case CertificateSignRequestResult::Valid:
+        return "Valid";
+    case CertificateSignRequestResult::KeyGenerationError:
+        return "KeyGenerationError";
+    case CertificateSignRequestResult::VersioningError:
+        return "VersioningError";
+    case CertificateSignRequestResult::PubkeyError:
+        return "PubkeyError";
+    case CertificateSignRequestResult::ExtensionsError:
+        return "ExtensionsError";
+    case CertificateSignRequestResult::SigningError:
+        return "SigningError";
+    }
+
+    throw std::out_of_range("No known string conversion for provided enum of type CertificateSignRequestResult");
+}
+
+} // namespace conversions
+
+} // namespace evse_security

lib/evse_security/crypto/openssl/openssl_supplier.cpp

@@ -703,7 +703,8 @@ bool OpenSSLSupplier::x509_verify_signature(X509Handle* handle, const std::vecto
     }
 }
 
-bool OpenSSLSupplier::x509_generate_csr(const CertificateSigningRequestInfo& csr_info, std::string& out_csr) {
+CertificateSignRequestResult OpenSSLSupplier::x509_generate_csr(const CertificateSigningRequestInfo& csr_info,
+                                                                std::string& out_csr) {
 
     KeyHandle_ptr gen_key;
     EVP_PKEY_CTX_ptr ctx;
@@ -717,7 +718,7 @@ bool OpenSSLSupplier::x509_generate_csr(const CertificateSigningRequestInfo& csr
     }
 
     if (false == s_generate_key(csr_info.key_info, gen_key, ctx)) {
-        return false;
+        return CertificateSignRequestResult::KeyGenerationError;
     }
 
     EVP_PKEY* key = get(gen_key.get());
@@ -730,13 +731,13 @@ bool OpenSSLSupplier::x509_generate_csr(const CertificateSigningRequestInfo& csr
 
     if (false == X509_REQ_set_version(x509_req_ptr.get(), n_version)) {
         EVLOG_error << "Failed to set csr version!";
-        return false;
+        return CertificateSignRequestResult::VersioningError;
     }
 
     // set public key of x509 req
     if (false == X509_REQ_set_pubkey(x509_req_ptr.get(), key)) {
         EVLOG_error << "Failed to set csr pubkey!";
-        return false;
+        return CertificateSignRequestResult::PubkeyError;
     }
 
     X509_NAME* x509Name = X509_REQ_get_subject_name(x509_req_ptr.get());
@@ -777,9 +778,10 @@ bool OpenSSLSupplier::x509_generate_csr(const CertificateSigningRequestInfo& csr
     X509_EXTENSION_free(ext_basic_constraints);
     X509_EXTENSION_free(ext_san);
     sk_X509_EXTENSION_free(extensions);
+
     if (!result) {
         EVLOG_error << "Failed to add csr extensions!";
-        return false;
+        return CertificateSignRequestResult::ExtensionsError;
     }
 
     // sign the certificate with the private key
@@ -789,7 +791,7 @@ bool OpenSSLSupplier::x509_generate_csr(const CertificateSigningRequestInfo& csr
 
     if (x509_signed == false) {
         EVLOG_error << "Failed to sign csr!";
-        return false;
+        return CertificateSignRequestResult::SigningError;
     }
 
     // write csr
@@ -800,7 +802,8 @@ bool OpenSSLSupplier::x509_generate_csr(const CertificateSigningRequestInfo& csr
     BIO_get_mem_ptr(bio.get(), &mem_csr);
 
     out_csr = std::string(mem_csr->data, mem_csr->length);
-    return true;
+
+    return CertificateSignRequestResult::Valid;
 }
 
 bool OpenSSLSupplier::digest_file_sha256(const fs::path& path, std::vector<std::uint8_t>& out_digest) {