cache default SSL root cert store

2 files changed, 124 insertions, 65 deletions

diff --git a/src/core/lib/security/security_connector/security_connector.cc b/src/core/lib/security/security_connector/security_connector.cc
index cbe77d5a69..3967112bb8 100644
--- a/src/core/lib/security/security_connector/security_connector.cc
+++ b/src/core/lib/security/security_connector/security_connector.cc
@@ -965,63 +965,6 @@ static grpc_security_connector_vtable ssl_channel_vtable = {
 static grpc_security_connector_vtable ssl_server_vtable = {
     ssl_server_destroy, ssl_server_check_peer, ssl_server_cmp};
 
-/* returns a NULL terminated slice. */
-static grpc_slice compute_default_pem_root_certs_once(void) {
-  grpc_slice result = grpc_empty_slice();
-
-  /* First try to load the roots from the environment. */
-  char* default_root_certs_path =
-      gpr_getenv(GRPC_DEFAULT_SSL_ROOTS_FILE_PATH_ENV_VAR);
-  if (default_root_certs_path != nullptr) {
-    GRPC_LOG_IF_ERROR("load_file",
-                      grpc_load_file(default_root_certs_path, 1, &result));
-    gpr_free(default_root_certs_path);
-  }
-
-  /* Try overridden roots if needed. */
-  grpc_ssl_roots_override_result ovrd_res = GRPC_SSL_ROOTS_OVERRIDE_FAIL;
-  if (GRPC_SLICE_IS_EMPTY(result) && ssl_roots_override_cb != nullptr) {
-    char* pem_root_certs = nullptr;
-    ovrd_res = ssl_roots_override_cb(&pem_root_certs);
-    if (ovrd_res == GRPC_SSL_ROOTS_OVERRIDE_OK) {
-      GPR_ASSERT(pem_root_certs != nullptr);
-      result = grpc_slice_from_copied_buffer(
-          pem_root_certs,
-          strlen(pem_root_certs) + 1);  // NULL terminator.
-    }
-    gpr_free(pem_root_certs);
-  }
-
-  /* Fall back to installed certs if needed. */
-  if (GRPC_SLICE_IS_EMPTY(result) &&
-      ovrd_res != GRPC_SSL_ROOTS_OVERRIDE_FAIL_PERMANENTLY) {
-    GRPC_LOG_IF_ERROR("load_file",
-                      grpc_load_file(installed_roots_path, 1, &result));
-  }
-  return result;
-}
-
-static grpc_slice default_pem_root_certs;
-
-static void init_default_pem_root_certs(void) {
-  default_pem_root_certs = compute_default_pem_root_certs_once();
-}
-
-grpc_slice grpc_get_default_ssl_roots_for_testing(void) {
-  return compute_default_pem_root_certs_once();
-}
-
-const char* grpc_get_default_ssl_roots(void) {
-  /* TODO(jboeuf@google.com): Maybe revisit the approach which consists in
-     loading all the roots once for the lifetime of the process. */
-  static gpr_once once = GPR_ONCE_INIT;
-  gpr_once_init(&once, init_default_pem_root_certs);
-  return GRPC_SLICE_IS_EMPTY(default_pem_root_certs)
-             ? nullptr
-             : reinterpret_cast<const char*>
-                   GRPC_SLICE_START_PTR(default_pem_root_certs);
-}
-
 grpc_security_status grpc_ssl_channel_security_connector_create(
     grpc_channel_credentials* channel_creds,
     grpc_call_credentials* request_metadata_creds,
@@ -1043,7 +986,9 @@ grpc_security_status grpc_ssl_channel_security_connector_create(
     goto error;
   }
   if (config->pem_root_certs == nullptr) {
-    options.pem_root_certs = grpc_get_default_ssl_roots();
+    // Use default root certificates.
+    options.pem_root_certs = grpc_core::DefaultSslRootStore::GetPemRootCerts();
+    options.root_store = grpc_core::DefaultSslRootStore::GetRootStore();
     if (options.pem_root_certs == nullptr) {
       gpr_log(GPR_ERROR, "Could not get default pem root certs.");
       goto error;
@@ -1051,7 +996,6 @@ grpc_security_status grpc_ssl_channel_security_connector_create(
   } else {
     options.pem_root_certs = config->pem_root_certs;
   }
-
   c = static_cast<grpc_ssl_channel_security_connector*>(
       gpr_zalloc(sizeof(grpc_ssl_channel_security_connector)));
 
@@ -1157,3 +1101,79 @@ grpc_security_status grpc_ssl_server_security_connector_create(
   }
   return retval;
 }
+
+namespace grpc_core {
+
+tsi_ssl_root_certs_store* DefaultSslRootStore::default_root_store_;
+grpc_slice DefaultSslRootStore::default_pem_root_certs_;
+
+const tsi_ssl_root_certs_store* DefaultSslRootStore::GetRootStore() {
+  InitRootStore();
+  return default_root_store_;
+}
+
+const char* DefaultSslRootStore::GetPemRootCerts() {
+  InitRootStore();
+  return GRPC_SLICE_IS_EMPTY(default_pem_root_certs_)
+             ? nullptr
+             : reinterpret_cast<const char*>
+                   GRPC_SLICE_START_PTR(default_pem_root_certs_);
+}
+
+void DefaultSslRootStore::Initialize() {
+  default_root_store_ = nullptr;
+  default_pem_root_certs_ = grpc_empty_slice();
+}
+
+void DefaultSslRootStore::Destroy() {
+  tsi_ssl_root_certs_store_destroy(default_root_store_);
+  grpc_slice_unref_internal(default_pem_root_certs_);
+}
+
+grpc_slice DefaultSslRootStore::ComputePemRootCerts() {
+  grpc_slice result = grpc_empty_slice();
+  // First try to load the roots from the environment.
+  char* default_root_certs_path =
+      gpr_getenv(GRPC_DEFAULT_SSL_ROOTS_FILE_PATH_ENV_VAR);
+  if (default_root_certs_path != nullptr) {
+    GRPC_LOG_IF_ERROR("load_file",
+                      grpc_load_file(default_root_certs_path, 1, &result));
+    gpr_free(default_root_certs_path);
+  }
+  // Try overridden roots if needed.
+  grpc_ssl_roots_override_result ovrd_res = GRPC_SSL_ROOTS_OVERRIDE_FAIL;
+  if (GRPC_SLICE_IS_EMPTY(result) && ssl_roots_override_cb != nullptr) {
+    char* pem_root_certs = nullptr;
+    ovrd_res = ssl_roots_override_cb(&pem_root_certs);
+    if (ovrd_res == GRPC_SSL_ROOTS_OVERRIDE_OK) {
+      GPR_ASSERT(pem_root_certs != nullptr);
+      result = grpc_slice_from_copied_buffer(
+          pem_root_certs,
+          strlen(pem_root_certs) + 1);  // nullptr terminator.
+    }
+    gpr_free(pem_root_certs);
+  }
+  // Fall back to installed certs if needed.
+  if (GRPC_SLICE_IS_EMPTY(result) &&
+      ovrd_res != GRPC_SSL_ROOTS_OVERRIDE_FAIL_PERMANENTLY) {
+    GRPC_LOG_IF_ERROR("load_file",
+                      grpc_load_file(installed_roots_path, 1, &result));
+  }
+  return result;
+}
+
+void DefaultSslRootStore::InitRootStore() {
+  static gpr_once once = GPR_ONCE_INIT;
+  gpr_once_init(&once, DefaultSslRootStore::InitRootStoreOnce);
+}
+
+void DefaultSslRootStore::InitRootStoreOnce() {
+  default_pem_root_certs_ = ComputePemRootCerts();
+  if (!GRPC_SLICE_IS_EMPTY(default_pem_root_certs_)) {
+    default_root_store_ =
+        tsi_ssl_root_certs_store_create(reinterpret_cast<const char*>(
+            GRPC_SLICE_START_PTR(default_pem_root_certs_)));
+  }
+}
+
+}  // namespace grpc_core
diff --git a/src/core/lib/security/security_connector/security_connector.h b/src/core/lib/security/security_connector/security_connector.h
index dc847d94f9..5d3d1e0f44 100644
--- a/src/core/lib/security/security_connector/security_connector.h
+++ b/src/core/lib/security/security_connector/security_connector.h
@@ -216,12 +216,6 @@ grpc_security_status grpc_ssl_channel_security_connector_create(
     tsi_ssl_session_cache* ssl_session_cache,
     grpc_channel_security_connector** sc);
 
-/* Gets the default ssl roots. Returns NULL if not found. */
-const char* grpc_get_default_ssl_roots(void);
-
-/* Exposed for TESTING ONLY!. */
-grpc_slice grpc_get_default_ssl_roots_for_testing(void);
-
 /* Config for ssl servers. */
 typedef struct {
   tsi_ssl_pem_key_cert_pair* pem_key_cert_pairs;
@@ -250,4 +244,49 @@ tsi_peer tsi_shallow_peer_from_ssl_auth_context(
     const grpc_auth_context* auth_context);
 void tsi_shallow_peer_destruct(tsi_peer* peer);
 
+/* --- Default SSL Root Store. --- */
+namespace grpc_core {
+
+// The class implements default SSL root store.
+class DefaultSslRootStore {
+ public:
+  // Gets the default SSL root store. Returns nullptr if not found.
+  static const tsi_ssl_root_certs_store* GetRootStore();
+
+  // Gets the default PEM root certificate.
+  static const char* GetPemRootCerts();
+
+  // Initializes the SSL root store's underlying data structure. It does not
+  // load default SSL root certificates. Should only be called by
+  // grpc_security_init().
+  static void Initialize();
+
+  // Destroys the default SSL root store. Should only be called by
+  // grpc_security_shutdown().
+  static void Destroy();
+
+ protected:
+  // Returns default PEM root certificates in nullptr terminated grpc_slice.
+  // This function is protected instead of private, so that it can be tested.
+  static grpc_slice ComputePemRootCerts();
+
+ private:
+  // Construct me not!
+  DefaultSslRootStore();
+
+  // Initialization of default SSL root store.
+  static void InitRootStore();
+
+  // One-time initialization of default SSL root store.
+  static void InitRootStoreOnce();
+
+  // SSL root store in tsi_ssl_root_certs_store object.
+  static tsi_ssl_root_certs_store* default_root_store_;
+
+  // Default PEM root certificates.
+  static grpc_slice default_pem_root_certs_;
+};
+
+}  // namespace grpc_core
+
 #endif /* GRPC_CORE_LIB_SECURITY_SECURITY_CONNECTOR_SECURITY_CONNECTOR_H */