1 files changed, 114 insertions, 0 deletions
diff --git a/src/core/tsi/alts/frame_protector/alts_record_protocol_crypter_common.cc b/src/core/tsi/alts/frame_protector/alts_record_protocol_crypter_common.cc
new file mode 100644
index 0000000000..0574ed5012
--- /dev/null
+++ b/src/core/tsi/alts/frame_protector/alts_record_protocol_crypter_common.cc
@@ -0,0 +1,114 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#include <grpc/support/port_platform.h>
+
+#include "src/core/tsi/alts/frame_protector/alts_record_protocol_crypter_common.h"
+
+#include <grpc/support/alloc.h>
+
+static void maybe_copy_error_msg(const char* src, char** dst) {
+  if (dst != nullptr && src != nullptr) {
+    *dst = static_cast<char*>(gpr_malloc(strlen(src) + 1));
+    memcpy(*dst, src, strlen(src) + 1);
+  }
+}
+
+grpc_status_code input_sanity_check(
+    const alts_record_protocol_crypter* rp_crypter, const unsigned char* data,
+    size_t* output_size, char** error_details) {
+  if (rp_crypter == nullptr) {
+    maybe_copy_error_msg("alts_crypter instance is nullptr.", error_details);
+    return GRPC_STATUS_INVALID_ARGUMENT;
+  } else if (data == nullptr) {
+    maybe_copy_error_msg("data is nullptr.", error_details);
+    return GRPC_STATUS_INVALID_ARGUMENT;
+  } else if (output_size == nullptr) {
+    maybe_copy_error_msg("output_size is nullptr.", error_details);
+    return GRPC_STATUS_INVALID_ARGUMENT;
+  }
+  return GRPC_STATUS_OK;
+}
+
+grpc_status_code increment_counter(alts_record_protocol_crypter* rp_crypter,
+                                   char** error_details) {
+  bool is_overflow = false;
+  grpc_status_code status =
+      alts_counter_increment(rp_crypter->ctr, &is_overflow, error_details);
+  if (status != GRPC_STATUS_OK) {
+    return status;
+  }
+  if (is_overflow) {
+    const char error_msg[] =
+        "crypter counter is wrapped. The connection"
+        "should be closed and the key should be deleted.";
+    maybe_copy_error_msg(error_msg, error_details);
+    return GRPC_STATUS_INTERNAL;
+  }
+  return GRPC_STATUS_OK;
+}
+
+size_t alts_record_protocol_crypter_num_overhead_bytes(const alts_crypter* c) {
+  if (c != nullptr) {
+    size_t num_overhead_bytes = 0;
+    char* error_details = nullptr;
+    const alts_record_protocol_crypter* rp_crypter =
+        reinterpret_cast<const alts_record_protocol_crypter*>(c);
+    grpc_status_code status = gsec_aead_crypter_tag_length(
+        rp_crypter->crypter, &num_overhead_bytes, &error_details);
+    if (status == GRPC_STATUS_OK) {
+      return num_overhead_bytes;
+    }
+  }
+  return 0;
+}
+
+void alts_record_protocol_crypter_destruct(alts_crypter* c) {
+  if (c != nullptr) {
+    alts_record_protocol_crypter* rp_crypter =
+        reinterpret_cast<alts_record_protocol_crypter*>(c);
+    alts_counter_destroy(rp_crypter->ctr);
+    gsec_aead_crypter_destroy(rp_crypter->crypter);
+  }
+}
+
+alts_record_protocol_crypter* alts_crypter_create_common(
+    gsec_aead_crypter* crypter, bool is_client, size_t overflow_size,
+    char** error_details) {
+  if (crypter != nullptr) {
+    auto* rp_crypter = static_cast<alts_record_protocol_crypter*>(
+        gpr_malloc(sizeof(alts_record_protocol_crypter)));
+    size_t counter_size = 0;
+    grpc_status_code status =
+        gsec_aead_crypter_nonce_length(crypter, &counter_size, error_details);
+    if (status != GRPC_STATUS_OK) {
+      return nullptr;
+    }
+    /* Create a counter. */
+    status = alts_counter_create(is_client, counter_size, overflow_size,
+                                 &rp_crypter->ctr, error_details);
+    if (status != GRPC_STATUS_OK) {
+      return nullptr;
+    }
+    rp_crypter->crypter = crypter;
+    return rp_crypter;
+  }
+  const char error_msg[] = "crypter is nullptr.";
+  maybe_copy_error_msg(error_msg, error_details);
+  return nullptr;
+}