fix(crypto): OpenSSL 4.x compatibility

src/crypto.cpp

@@ -11,6 +11,7 @@
 
 namespace crypto {
   using asn1_string_t = util::safe_ptr<ASN1_STRING, ASN1_STRING_free>;
+  using x509_name_t = util::safe_ptr<X509_NAME, &X509_NAME_free>;
 
   cert_chain_t::cert_chain_t():
       _certs {},
@@ -391,7 +392,10 @@ namespace crypto {
     const ASN1_BIT_STRING *asn1 = nullptr;
     X509_get0_signature(&asn1, nullptr, x.get());
 
-    return {(const char *) asn1->data, (std::size_t) asn1->length};
+    return {
+      reinterpret_cast<const char *>(ASN1_STRING_get0_data(asn1)),
+      static_cast<std::size_t>(ASN1_STRING_length(asn1))
+    };
   }
 
   std::string rand(std::size_t bytes) {
@@ -461,10 +465,11 @@ namespace crypto {
 
     X509_set_pubkey(x509.get(), pkey.get());
 
-    auto name = X509_get_subject_name(x509.get());
-    X509_NAME_add_entry_by_txt(name, "CN", MBSTRING_ASC, (const std::uint8_t *) cn.data(), (int) cn.size(), -1, 0);
+    x509_name_t name {X509_NAME_new()};
+    X509_NAME_add_entry_by_txt(name.get(), "CN", MBSTRING_ASC, reinterpret_cast<const std::uint8_t *>(cn.data()), (int) cn.size(), -1, 0);
 
-    X509_set_issuer_name(x509.get(), name);
+    X509_set_subject_name(x509.get(), name.get());
+    X509_set_issuer_name(x509.get(), name.get());
     X509_sign(x509.get(), pkey.get(), EVP_sha256());
 
     return {pem(x509), pem(pkey)};

tests/unit/test_crypto.cpp

@@ -0,0 +1,50 @@
+/**
+ * @file tests/unit/test_crypto.cpp
+ * @brief Test src/crypto.*.
+ */
+// test imports
+#include "../tests_common.h"
+
+// lib imports
+#include <openssl/x509.h>
+
+// local imports
+#include <src/crypto.h>
+
+TEST(CryptoTest, GeneratedCredentialsExposeSubjectAndVerifySignatures) {
+  constexpr std::string_view common_name = "Sunshine Test Host";
+  constexpr std::string_view payload = "payload";
+
+  auto creds = crypto::gen_creds(common_name, 2048);
+  ASSERT_FALSE(creds.x509.empty());
+  ASSERT_FALSE(creds.pkey.empty());
+
+  auto cert = crypto::x509(creds.x509);
+  auto pkey = crypto::pkey(creds.pkey);
+  ASSERT_NE(cert.get(), nullptr);
+  ASSERT_NE(pkey.get(), nullptr);
+
+  const auto subject = X509_get_subject_name(cert.get());
+  ASSERT_NE(subject, nullptr);
+
+  const auto common_name_index = X509_NAME_get_index_by_NID(subject, NID_commonName, -1);
+  ASSERT_GE(common_name_index, 0);
+
+  const auto common_name_entry = X509_NAME_get_entry(subject, common_name_index);
+  ASSERT_NE(common_name_entry, nullptr);
+
+  const auto common_name_data = X509_NAME_ENTRY_get_data(common_name_entry);
+  ASSERT_NE(common_name_data, nullptr);
+
+  const std::string_view parsed_common_name {
+    reinterpret_cast<const char *>(ASN1_STRING_get0_data(common_name_data)),
+    static_cast<std::size_t>(ASN1_STRING_length(common_name_data))
+  };
+  ASSERT_EQ(parsed_common_name, common_name);
+
+  ASSERT_FALSE(crypto::signature(cert).empty());
+
+  const auto signature = crypto::sign256(pkey, payload);
+  ASSERT_FALSE(signature.empty());
+  ASSERT_TRUE(crypto::verify256(cert, payload, {reinterpret_cast<const char *>(signature.data()), signature.size()}));
+}