security: Do not let grpc reload ssh cert if not changed (#9068) (#9070)

ref #8535

.github/licenserc.yml

@@ -43,5 +43,6 @@ header:
     - '**/OWNERS'
     - 'OWNERS_ALIASES'
     - '**/*.sql'
+    - 'dbms/src/Common/tests/tls/'
 
   comment: on-failure

dbms/src/Common/TiFlashSecurity.h

@@ -177,11 +177,13 @@ class TiFlashSecurityConfig : public ConfigObject
         return allowed_common_names.count(cert.commonName()) > 0;
     }
 
-    grpc::SslCredentialsOptions readAndCacheSslCredentialOptions()
+    std::optional<grpc::SslCredentialsOptions> readAndCacheSslCredentialOptions()
     {
         std::unique_lock lock(mu);
+        // if ssl_cerd_options_cached = true, it means the same options has already been returned to grpc-core
+        // don't need to return it again if ssl cert is not actually changed
         if (ssl_cerd_options_cached)
-            return options;
+            return {};
         options.pem_root_certs = readFile(ca_path);
         options.pem_cert_chain = readFile(cert_path);
         options.pem_private_key = readFile(key_path);

dbms/src/Common/tests/gtest_tiflash_security.cpp

@@ -13,6 +13,8 @@
 // limitations under the License.
 
 #include <Common/TiFlashSecurity.h>
+#include <Poco/File.h>
+#include <Poco/FileStream.h>
 #include <TestUtils/ConfigTestUtils.h>
 #include <gtest/gtest.h>
 
@@ -188,5 +190,86 @@ redact_info_log=false
     ASSERT_TRUE(tiflash_config_2.allowedCommonNames().empty());
     ASSERT_FALSE(tiflash_config_2.hasTlsConfig());
 }
+
+String createConfigString(String & ca_path, String & cert_path, String & key_path)
+{
+    String ret =
+        R"(
+[security]
+ca_path=")";
+    ret += ca_path;
+    ret += R"("
+cert_path=")";
+    ret += cert_path;
+    ret += R"("
+key_path=")";
+    ret += key_path;
+    ret += R"("
+)";
+    return ret;
+}
+
+TEST(TiFlashSecurityTest, readAndCacheSslCredentialOptions)
+{
+    const auto & test_info = testing::UnitTest::GetInstance()->current_test_info();
+    assert(test_info);
+    String file_name = test_info->file();
+    auto pos = file_name.find_last_of('/');
+    auto file_path = file_name.substr(0, pos);
+    // these certs are copied from https://github.com/grpc/grpc/tree/v1.64.0/src/python/grpcio_tests/tests/unit/credentials
+    auto ca_path = file_path + "/tls/ca.crt";
+    auto cert_path = file_path + "/tls/cert.crt";
+    auto key_path = file_path + "/tls/key.pem";
+    auto test = createConfigString(ca_path, cert_path, key_path);
+    auto config = loadConfigFromString(test);
+    const auto log = Logger::get();
+    TiFlashSecurityConfig tiflash_config(log);
+    tiflash_config.init(*config);
+    // first read will return a valid options
+    auto options = tiflash_config.readAndCacheSslCredentialOptions();
+    ASSERT_TRUE(options.has_value());
+    // not return valid options if cert is not changed
+    auto new_options = tiflash_config.readAndCacheSslCredentialOptions();
+    ASSERT_FALSE(new_options.has_value());
+    ca_path = file_path + "/tls/ca.crt.new";
+    cert_path = file_path + "/tls/cert.crt.new";
+    key_path = file_path + "/tls/key.pem.new";
+    {
+        Poco::FileOutputStream ca_fos(ca_path);
+        ca_fos << options.value().pem_root_certs;
+        Poco::FileOutputStream cert_fos(cert_path);
+        cert_fos << options.value().pem_cert_chain;
+        Poco::FileOutputStream key_fos(key_path);
+        key_fos << options.value().pem_private_key;
+    }
+    test = createConfigString(ca_path, cert_path, key_path);
+    config = loadConfigFromString(test);
+    ASSERT_TRUE(tiflash_config.update(*config));
+    // return a valid options if cert is changed
+    options = tiflash_config.readAndCacheSslCredentialOptions();
+    ASSERT_TRUE(options.has_value());
+    new_options = tiflash_config.readAndCacheSslCredentialOptions();
+    ASSERT_FALSE(new_options.has_value());
+    using namespace std::chrono_literals;
+    std::this_thread::sleep_for(1s);
+    {
+        // change the modified time
+        Poco::FileOutputStream fos(ca_path);
+        fos << options.value().pem_root_certs;
+    }
+    new_options = tiflash_config.readAndCacheSslCredentialOptions();
+    // no aware of the change since `update` is not called
+    ASSERT_FALSE(new_options.has_value());
+    ASSERT_TRUE(tiflash_config.update(*config));
+    // aware of the change and return a new options
+    new_options = tiflash_config.readAndCacheSslCredentialOptions();
+    ASSERT_TRUE(new_options.has_value());
+    Poco::File ca_file(ca_path);
+    ca_file.remove(false);
+    Poco::File cert_file(cert_path);
+    cert_file.remove(false);
+    Poco::File key_file(key_path);
+    key_file.remove(false);
+}
 } // namespace tests
 } // namespace DB

dbms/src/Common/tests/tls/ca.crt

@@ -0,0 +1,20 @@
+-----BEGIN CERTIFICATE-----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==
+-----END CERTIFICATE-----

dbms/src/Common/tests/tls/cert.crt

@@ -0,0 +1,22 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----

dbms/src/Common/tests/tls/key.pem

@@ -0,0 +1,28 @@
+-----BEGIN PRIVATE KEY-----
+MIIEvwIBADANBgkqhkiG9w0BAQEFAASCBKkwggSlAgEAAoIBAQDnE443EknxvxBq
+6+hvn/t09hl8hx366EBYvZmVM/NC+7igXRAjiJiA/mIaCvL3MS0Iz5hBLxSGICU+
+WproA3GCIFITIwcf/ETyWj/5xpgZ4AKrLrjQmmX8mhwUajfF3UvwMJrCOVqPp67t
+PtP+2kBXaqrXdvnvXR41FsIB8V7zIAuIZB6bHQhiGVlc1sgZYsE2EGG9WMmHtS86
+qkAOTjG2XyjmPTGAwhGDpYkYrpzp99IiDh4/Veai81hn0ssQkbry0XRD/Ig3jcHh
+23WiriPNJ0JsbgXUSLKRPZObA9VgOLy2aXoN84IMaeK3yy+cwSYG/99w93fUZJte
+MXwz4oYZAgMBAAECggEBAIVn2Ncai+4xbH0OLWckabwgyJ4IM9rDc0LIU368O1kU
+koais8qP9dujAWgfoh3sGh/YGgKn96VnsZjKHlyMgF+r4TaDJn3k2rlAOWcurGlj
+1qaVlsV4HiEzp7pxiDmHhWvp4672Bb6iBG+bsjCUOEk/n9o9KhZzIBluRhtxCmw5
+nw4Do7z00PTvN81260uPWSc04IrytvZUiAIx/5qxD72bij2xJ8t/I9GI8g4FtoVB
+8pB6S/hJX1PZhh9VlU6Yk+TOfOVnbebG4W5138LkB835eqk3Zz0qsbc2euoi8Hxi
+y1VGwQEmMQ63jXz4c6g+X55ifvUK9Jpn5E8pq+pMd7ECgYEA93lYq+Cr54K4ey5t
+sWMa+ye5RqxjzgXj2Kqr55jb54VWG7wp2iGbg8FMlkQwzTJwebzDyCSatguEZLuB
+gRGroRnsUOy9vBvhKPOch9bfKIl6qOgzMJB267fBVWx5ybnRbWN/I7RvMQf3k+9y
+biCIVnxDLEEYyx7z85/5qxsXg/MCgYEA7wmWKtCTn032Hy9P8OL49T0X6Z8FlkDC
+Rk42ygrc/MUbugq9RGUxcCxoImOG9JXUpEtUe31YDm2j+/nbvrjl6/bP2qWs0V7l
+dTJl6dABP51pCw8+l4cWgBBX08Lkeen812AAFNrjmDCjX6rHjWHLJcpS18fnRRkP
+V1d/AHWX7MMCgYEA6Gsw2guhp0Zf2GCcaNK5DlQab8OL4Hwrpttzo4kuTlwtqNKp
+Q9H4al9qfF4Cr1TFya98+EVYf8yFRM3NLNjZpe3gwYf2EerlJj7VLcahw0KKzoN1
+QBENfwgPLRk5sDkx9VhSmcfl/diLroZdpAwtv3vo4nEoxeuGFbKTGx3Qkf0CgYEA
+xyR+dcb05Ygm3w4klHQTowQ10s1H80iaUcZBgQuR1ghEtDbUPZHsoR5t1xCB02ys
+DgAwLv1bChIvxvH/L6KM8ovZ2LekBX4AviWxoBxJnfz/EVau98B0b1auRN6eSC83
+FRuGldlSOW1z/nSh8ViizSYE5H5HX1qkXEippvFRE88CgYB3Bfu3YQY60ITWIShv
+nNkdcbTT9eoP9suaRJjw92Ln+7ZpALYlQMKUZmJ/5uBmLs4RFwUTQruLOPL4yLTH
+awADWUzs3IRr1fwn9E+zM8JVyKCnUEM3w4N5UZskGO2klashAd30hWO+knRv/y0r
+uGIYs9Ek7YXlXIRVrzMwcsrt1w==
+-----END PRIVATE KEY-----

dbms/src/Server/FlashGrpcServerHolder.cpp

@@ -93,9 +93,15 @@ static grpc_ssl_certificate_config_reload_status sslServerCertificateConfigCallb
     }
     auto * context = static_cast<Context *>(arg);
     auto options = context->getSecurityConfig()->readAndCacheSslCredentialOptions();
-    grpc_ssl_pem_key_cert_pair pem_key_cert_pair = {options.pem_private_key.c_str(), options.pem_cert_chain.c_str()};
-    *config = grpc_ssl_server_certificate_config_create(options.pem_root_certs.c_str(), &pem_key_cert_pair, 1);
-    return GRPC_SSL_CERTIFICATE_CONFIG_RELOAD_NEW;
+    if (options.has_value())
+    {
+        grpc_ssl_pem_key_cert_pair pem_key_cert_pair
+            = {options.value().pem_private_key.c_str(), options.value().pem_cert_chain.c_str()};
+        *config
+            = grpc_ssl_server_certificate_config_create(options.value().pem_root_certs.c_str(), &pem_key_cert_pair, 1);
+        return GRPC_SSL_CERTIFICATE_CONFIG_RELOAD_NEW;
+    }
+    return GRPC_SSL_CERTIFICATE_CONFIG_RELOAD_UNCHANGED;
 }
 
 grpc_server_credentials * grpcSslServerCredentialsCreateWithFetcher(