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41 results

credentials_test.c

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  • credentials_test.c 39.51 KiB
    /*
     *
     * Copyright 2015, Google Inc.
     * All rights reserved.
     *
     * Redistribution and use in source and binary forms, with or without
     * modification, are permitted provided that the following conditions are
     * met:
     *
     *     * Redistributions of source code must retain the above copyright
     * notice, this list of conditions and the following disclaimer.
     *     * Redistributions in binary form must reproduce the above
     * copyright notice, this list of conditions and the following disclaimer
     * in the documentation and/or other materials provided with the
     * distribution.
     *     * Neither the name of Google Inc. nor the names of its
     * contributors may be used to endorse or promote products derived from
     * this software without specific prior written permission.
     *
     * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
     * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     *
     */
    
    #include "src/core/security/credentials.h"
    
    #include <string.h>
    
    #include "src/core/httpcli/httpcli.h"
    #include "src/core/security/json_token.h"
    #include "src/core/support/env.h"
    #include "src/core/support/file.h"
    #include "src/core/support/string.h"
    
    #include "test/core/util/test_config.h"
    
    #include <grpc/support/alloc.h>
    #include <grpc/support/log.h>
    #include <grpc/support/string_util.h>
    #include <grpc/support/time.h>
    
    #include <openssl/rsa.h>
    
    static const char test_google_iam_authorization_token[] = "blahblahblhahb";
    static const char test_google_iam_authority_selector[] = "respectmyauthoritah";
    static const char test_oauth2_bearer_token[] = "Bearer blaaslkdjfaslkdfasdsfasf";
    static const char test_root_cert[] = "I am the root!";
    
    /* This JSON key was generated with the GCE console and revoked immediately.
       The identifiers have been changed as well.
       Maximum size for a string literal is 509 chars in C89, yay!  */
    static const char test_json_key_str_part1[] = "{ \"private_key\": \"-----BEGIN PRIVATE KEY-----" "\\nMIICeAIBADANBgkqhkiG9w0BAQEFAASCAmIwggJeAgEAAoGBAOEvJsnoHnyHkXcp\\n7mJE" "qg" "WGjiw71NfXByguekSKho65FxaGbsnSM9SMQAqVk7Q2rG+I0OpsT0LrWQtZ\\nyjSeg/" "rWBQvS4hle4LfijkP3J5BG+" "IXDMP8RfziNRQsenAXDNPkY4kJCvKux2xdD\\nOnVF6N7dL3nTYZg+" "uQrNsMTz9UxVAgMBAAECgYEAzbLewe1xe9vy+2GoSsfib+28\\nDZgSE6Bu/" "zuFoPrRc6qL9p2SsnV7txrunTyJkkOnPLND9ABAXybRTlcVKP/sGgza\\n/" "8HpCqFYM9V8f34SBWfD4fRFT+n/" "73cfRUtGXdXpseva2lh8RilIQfPhNZAncenU\\ngqXjDvpkypEusgXAykECQQD+";
    static const char test_json_key_str_part2[] = "53XxNVnxBHsYb+AYEfklR96yVi8HywjVHP34+OQZ\\nCslxoHQM8s+" "dBnjfScLu22JqkPv04xyxmt0QAKm9+vTdAkEA4ib7YvEAn2jXzcCI\\nEkoy2L/" "XydR1GCHoacdfdAwiL2npOdnbvi4ZmdYRPY1LSTO058tQHKVXV7NLeCa3\\nAARh2QJBAMKeDA" "G" "W303SQv2cZTdbeaLKJbB5drz3eo3j7dDKjrTD9JupixFbzcGw\\n8FZi5c8idxiwC36kbAL6Hz" "A" "ZoX+ofI0CQE6KCzPJTtYNqyShgKAZdJ8hwOcvCZtf\\n6z8RJm0+" "6YBd38lfh5j8mZd7aHFf6I17j5AQY7oPEc47TjJj/" "5nZ68ECQQDvYuI3\\nLyK5fS8g0SYbmPOL9TlcHDOqwG0mrX9qpg5DC2fniXNSrrZ64GTDKdzZ" "Y" "Ap6LI9W\\nIqv4vr6y38N79TTC\\n-----END PRIVATE KEY-----\\n\", ";
    static const char test_json_key_str_part3[] = "\"private_key_id\": \"e6b5137873db8d2ef81e06a47289e6434ec8a165\", " "\"client_email\": " "\"777-abaslkan11hlb6nmim3bpspl31ud@developer.gserviceaccount." "com\", \"client_id\": " "\"777-abaslkan11hlb6nmim3bpspl31ud.apps.googleusercontent." "com\", \"type\": \"service_account\" }";
    
    /* Test refresh token. */
    static const char test_refresh_token_str[] = "{ \"client_id\": \"32555999999.apps.googleusercontent.com\"," "  \"client_secret\": \"EmssLNjJy1332hD4KFsecret\"," "  \"refresh_token\": \"1/Blahblasj424jladJDSGNf-u4Sua3HDA2ngjd42\"," "  \"type\": \"authorized_user\"}";
    
    static const char valid_oauth2_json_response[] = "{\"access_token\":\"ya29.AHES6ZRN3-HlhAPya30GnW_bHSb_\"," " \"expires_in\":3599, " " \"token_type\":\"Bearer\"}";
    
    static const char test_user_data[] = "user data";
    
    static const char test_scope[] = "perm1 perm2";
    
    static const char test_signed_jwt[] = "eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCIsImtpZCI6ImY0OTRkN2M1YWU2MGRmOTcyNmM4YW" "U0MDcyZTViYTdmZDkwODg2YzcifQ";
    
    static const char test_service_url[] = "https://foo.com/foo.v1";
    static const char other_test_service_url[] = "https://bar.com/bar.v1";
    
    static char *
    test_json_key_str (void)
    {
      size_t result_len = strlen (test_json_key_str_part1) + strlen (test_json_key_str_part2) + strlen (test_json_key_str_part3);
      char *result = gpr_malloc (result_len + 1);
      char *current = result;
      strcpy (result, test_json_key_str_part1);
      current += strlen (test_json_key_str_part1);
      strcpy (current, test_json_key_str_part2);
      current += strlen (test_json_key_str_part2);
      strcpy (current, test_json_key_str_part3);
      return result;
    }
    
    typedef struct
    {
      const char *key;
      const char *value;
    } expected_md;
    
    static grpc_httpcli_response
    http_response (int status, const char *body)
    {
      grpc_httpcli_response response;
      memset (&response, 0, sizeof (grpc_httpcli_response));
      response.status = status;
      response.body = (char *) body;
      response.body_length = strlen (body);
      return response;
    }
    
    static void
    test_empty_md_store (void)
    {
      grpc_credentials_md_store *store = grpc_credentials_md_store_create (0);
      GPR_ASSERT (store->num_entries == 0);
      GPR_ASSERT (store->allocated == 0);
      grpc_credentials_md_store_unref (store);
    }
    
    static void
    test_ref_unref_empty_md_store (void)
    {
      grpc_credentials_md_store *store = grpc_credentials_md_store_create (0);
      grpc_credentials_md_store_ref (store);
      grpc_credentials_md_store_ref (store);
      GPR_ASSERT (store->num_entries == 0);
      GPR_ASSERT (store->allocated == 0);
      grpc_credentials_md_store_unref (store);
      grpc_credentials_md_store_unref (store);
      grpc_credentials_md_store_unref (store);
    }
    
    static void
    test_add_to_empty_md_store (void)
    {
      grpc_credentials_md_store *store = grpc_credentials_md_store_create (0);
      const char *key_str = "hello";
      const char *value_str = "there blah blah blah blah blah blah blah";
      gpr_slice key = gpr_slice_from_copied_string (key_str);
      gpr_slice value = gpr_slice_from_copied_string (value_str);
      grpc_credentials_md_store_add (store, key, value);
      GPR_ASSERT (store->num_entries == 1);
      GPR_ASSERT (gpr_slice_cmp (key, store->entries[0].key) == 0);
      GPR_ASSERT (gpr_slice_cmp (value, store->entries[0].value) == 0);
      gpr_slice_unref (key);
      gpr_slice_unref (value);
      grpc_credentials_md_store_unref (store);
    }
    
    static void
    test_add_cstrings_to_empty_md_store (void)
    {
      grpc_credentials_md_store *store = grpc_credentials_md_store_create (0);
      const char *key_str = "hello";
      const char *value_str = "there blah blah blah blah blah blah blah";
      grpc_credentials_md_store_add_cstrings (store, key_str, value_str);
      GPR_ASSERT (store->num_entries == 1);
      GPR_ASSERT (gpr_slice_str_cmp (store->entries[0].key, key_str) == 0);
      GPR_ASSERT (gpr_slice_str_cmp (store->entries[0].value, value_str) == 0);
      grpc_credentials_md_store_unref (store);
    }
    
    static void
    test_empty_preallocated_md_store (void)
    {
      grpc_credentials_md_store *store = grpc_credentials_md_store_create (4);
      GPR_ASSERT (store->num_entries == 0);
      GPR_ASSERT (store->allocated == 4);
      GPR_ASSERT (store->entries != NULL);
      grpc_credentials_md_store_unref (store);
    }
    
    static void
    test_add_abunch_to_md_store (void)
    {
      grpc_credentials_md_store *store = grpc_credentials_md_store_create (4);
      size_t num_entries = 1000;
      const char *key_str = "hello";
      const char *value_str = "there blah blah blah blah blah blah blah";
      size_t i;
      for (i = 0; i < num_entries; i++)
        {
          grpc_credentials_md_store_add_cstrings (store, key_str, value_str);
        }
      for (i = 0; i < num_entries; i++)
        {
          GPR_ASSERT (gpr_slice_str_cmp (store->entries[i].key, key_str) == 0);
          GPR_ASSERT (gpr_slice_str_cmp (store->entries[i].value, value_str) == 0);
        }
      grpc_credentials_md_store_unref (store);
    }
    
    static void
    test_oauth2_token_fetcher_creds_parsing_ok (void)
    {
      grpc_credentials_md_store *token_md = NULL;
      gpr_timespec token_lifetime;
      grpc_httpcli_response response = http_response (200, valid_oauth2_json_response);
      GPR_ASSERT (grpc_oauth2_token_fetcher_credentials_parse_server_response (&response, &token_md, &token_lifetime) == GRPC_CREDENTIALS_OK);
      GPR_ASSERT (token_lifetime.tv_sec == 3599);
      GPR_ASSERT (token_lifetime.tv_nsec == 0);
      GPR_ASSERT (token_md->num_entries == 1);
      GPR_ASSERT (gpr_slice_str_cmp (token_md->entries[0].key, "Authorization") == 0);
      GPR_ASSERT (gpr_slice_str_cmp (token_md->entries[0].value, "Bearer ya29.AHES6ZRN3-HlhAPya30GnW_bHSb_") == 0);
      grpc_credentials_md_store_unref (token_md);
    }
    
    static void
    test_oauth2_token_fetcher_creds_parsing_bad_http_status (void)
    {
      grpc_credentials_md_store *token_md = NULL;
      gpr_timespec token_lifetime;
      grpc_httpcli_response response = http_response (401, valid_oauth2_json_response);
      GPR_ASSERT (grpc_oauth2_token_fetcher_credentials_parse_server_response (&response, &token_md, &token_lifetime) == GRPC_CREDENTIALS_ERROR);
    }
    
    static void
    test_oauth2_token_fetcher_creds_parsing_empty_http_body (void)
    {
      grpc_credentials_md_store *token_md = NULL;
      gpr_timespec token_lifetime;
      grpc_httpcli_response response = http_response (200, "");
      GPR_ASSERT (grpc_oauth2_token_fetcher_credentials_parse_server_response (&response, &token_md, &token_lifetime) == GRPC_CREDENTIALS_ERROR);
    }
    
    static void
    test_oauth2_token_fetcher_creds_parsing_invalid_json (void)
    {
      grpc_credentials_md_store *token_md = NULL;
      gpr_timespec token_lifetime;
      grpc_httpcli_response response = http_response (200,
    						  "{\"access_token\":\"ya29.AHES6ZRN3-HlhAPya30GnW_bHSb_\"," " \"expires_in\":3599, " " \"token_type\":\"Bearer\"");
      GPR_ASSERT (grpc_oauth2_token_fetcher_credentials_parse_server_response (&response, &token_md, &token_lifetime) == GRPC_CREDENTIALS_ERROR);
    }
    
    static void
    test_oauth2_token_fetcher_creds_parsing_missing_token (void)
    {
      grpc_credentials_md_store *token_md = NULL;
      gpr_timespec token_lifetime;
      grpc_httpcli_response response = http_response (200,
    						  "{" " \"expires_in\":3599, " " \"token_type\":\"Bearer\"}");
      GPR_ASSERT (grpc_oauth2_token_fetcher_credentials_parse_server_response (&response, &token_md, &token_lifetime) == GRPC_CREDENTIALS_ERROR);
    }
    
    static void
    test_oauth2_token_fetcher_creds_parsing_missing_token_type (void)
    {
      grpc_credentials_md_store *token_md = NULL;
      gpr_timespec token_lifetime;
      grpc_httpcli_response response = http_response (200,
    						  "{\"access_token\":\"ya29.AHES6ZRN3-HlhAPya30GnW_bHSb_\"," " \"expires_in\":3599, " "}");
      GPR_ASSERT (grpc_oauth2_token_fetcher_credentials_parse_server_response (&response, &token_md, &token_lifetime) == GRPC_CREDENTIALS_ERROR);
    }
    
    static void
    test_oauth2_token_fetcher_creds_parsing_missing_token_lifetime (void)
    {
      grpc_credentials_md_store *token_md = NULL;
      gpr_timespec token_lifetime;
      grpc_httpcli_response response = http_response (200,
    						  "{\"access_token\":\"ya29.AHES6ZRN3-HlhAPya30GnW_bHSb_\"," " \"token_type\":\"Bearer\"}");
      GPR_ASSERT (grpc_oauth2_token_fetcher_credentials_parse_server_response (&response, &token_md, &token_lifetime) == GRPC_CREDENTIALS_ERROR);
    }
    
    static void
    check_metadata (expected_md * expected, grpc_credentials_md * md_elems, size_t num_md)
    {
      size_t i;
      for (i = 0; i < num_md; i++)
        {
          size_t j;
          for (j = 0; j < num_md; j++)
    	{
    	  if (0 == gpr_slice_str_cmp (md_elems[j].key, expected[i].key))
    	    {
    	      GPR_ASSERT (gpr_slice_str_cmp (md_elems[j].value, expected[i].value) == 0);
    	      break;
    	    }
    	}
          if (j == num_md)
    	{
    	  gpr_log (GPR_ERROR, "key %s not found", expected[i].key);
    	  GPR_ASSERT (0);
    	}
        }
    }
    
    static void
    check_google_iam_metadata (grpc_exec_ctx * exec_ctx, void *user_data, grpc_credentials_md * md_elems, size_t num_md, grpc_credentials_status status)
    {
      grpc_credentials *c = (grpc_credentials *) user_data;
      expected_md emd[] = { {GRPC_IAM_AUTHORIZATION_TOKEN_METADATA_KEY,
    			 test_google_iam_authorization_token},
      {GRPC_IAM_AUTHORITY_SELECTOR_METADATA_KEY,
       test_google_iam_authority_selector}
      };
      GPR_ASSERT (status == GRPC_CREDENTIALS_OK);
      GPR_ASSERT (num_md == 2);
      check_metadata (emd, md_elems, num_md);
      grpc_credentials_unref (c);
    }
    
    static void
    test_google_iam_creds (void)
    {
      grpc_closure_list closure_list = GRPC_CLOSURE_LIST_INIT;
      grpc_credentials *creds = grpc_google_iam_credentials_create (test_google_iam_authorization_token, test_google_iam_authority_selector,
    								NULL);
      GPR_ASSERT (grpc_credentials_has_request_metadata (creds));
      GPR_ASSERT (grpc_credentials_has_request_metadata_only (creds));
      grpc_credentials_get_request_metadata (creds, NULL, test_service_url, check_google_iam_metadata, creds, &closure_list);
      grpc_closure_list_run (&closure_list);
    }
    
    static void
    check_access_token_metadata (grpc_exec_ctx * exec_ctx, void *user_data, grpc_credentials_md * md_elems, size_t num_md, grpc_credentials_status status)
    {
      grpc_credentials *c = (grpc_credentials *) user_data;
      expected_md emd[] = { {GRPC_AUTHORIZATION_METADATA_KEY, "Bearer blah"} };
      GPR_ASSERT (status == GRPC_CREDENTIALS_OK);
      GPR_ASSERT (num_md == 1);
      check_metadata (emd, md_elems, num_md);
      grpc_credentials_unref (c);
    }
    
    static void
    test_access_token_creds (void)
    {
      grpc_closure_list closure_list = GRPC_CLOSURE_LIST_INIT;
      grpc_credentials *creds = grpc_access_token_credentials_create ("blah", NULL);
      GPR_ASSERT (grpc_credentials_has_request_metadata (creds));
      GPR_ASSERT (grpc_credentials_has_request_metadata_only (creds));
      GPR_ASSERT (strcmp (creds->type, GRPC_CREDENTIALS_TYPE_OAUTH2) == 0);
      grpc_credentials_get_request_metadata (creds, NULL, test_service_url, check_access_token_metadata, creds, &closure_list);
      grpc_closure_list_run (&closure_list);
    }
    
    static void
    check_ssl_oauth2_composite_metadata (grpc_exec_ctx * exec_ctx, void *user_data, grpc_credentials_md * md_elems, size_t num_md, grpc_credentials_status status)
    {
      grpc_credentials *c = (grpc_credentials *) user_data;
      expected_md emd[] = {
        {GRPC_AUTHORIZATION_METADATA_KEY, test_oauth2_bearer_token}
      };
      GPR_ASSERT (status == GRPC_CREDENTIALS_OK);
      GPR_ASSERT (num_md == 1);
      check_metadata (emd, md_elems, num_md);
      grpc_credentials_unref (c);
    }
    
    static void
    test_ssl_oauth2_composite_creds (void)
    {
      grpc_closure_list closure_list = GRPC_CLOSURE_LIST_INIT;
      grpc_credentials *ssl_creds = grpc_ssl_credentials_create (test_root_cert, NULL, NULL);
      const grpc_credentials_array *creds_array;
      grpc_credentials *oauth2_creds = grpc_md_only_test_credentials_create ("Authorization", test_oauth2_bearer_token, 0);
      grpc_credentials *composite_creds = grpc_composite_credentials_create (ssl_creds, oauth2_creds, NULL);
      grpc_credentials_unref (ssl_creds);
      grpc_credentials_unref (oauth2_creds);
      GPR_ASSERT (strcmp (composite_creds->type, GRPC_CREDENTIALS_TYPE_COMPOSITE) == 0);
      GPR_ASSERT (grpc_credentials_has_request_metadata (composite_creds));
      GPR_ASSERT (!grpc_credentials_has_request_metadata_only (composite_creds));
      creds_array = grpc_composite_credentials_get_credentials (composite_creds);
      GPR_ASSERT (creds_array->num_creds == 2);
      GPR_ASSERT (strcmp (creds_array->creds_array[0]->type, GRPC_CREDENTIALS_TYPE_SSL) == 0);
      GPR_ASSERT (strcmp (creds_array->creds_array[1]->type, GRPC_CREDENTIALS_TYPE_OAUTH2) == 0);
      grpc_credentials_get_request_metadata (composite_creds, NULL, test_service_url, check_ssl_oauth2_composite_metadata, composite_creds, &closure_list);
      grpc_closure_list_run (&closure_list);
    }
    
    void
    test_ssl_fake_transport_security_composite_creds_failure (void)
    {
      grpc_credentials *ssl_creds = grpc_ssl_credentials_create (NULL, NULL, NULL);
      grpc_credentials *fake_transport_security_creds = grpc_fake_transport_security_credentials_create ();
    
      /* 2 connector credentials: should not work. */
      GPR_ASSERT (grpc_composite_credentials_create (ssl_creds, fake_transport_security_creds, NULL) == NULL);
      grpc_credentials_unref (ssl_creds);
      grpc_credentials_unref (fake_transport_security_creds);
    }
    
    static void
    check_ssl_oauth2_google_iam_composite_metadata (grpc_exec_ctx * exec_ctx, void *user_data, grpc_credentials_md * md_elems, size_t num_md, grpc_credentials_status status)
    {
      grpc_credentials *c = (grpc_credentials *) user_data;
      expected_md emd[] = {
        {GRPC_AUTHORIZATION_METADATA_KEY, test_oauth2_bearer_token},
        {GRPC_IAM_AUTHORIZATION_TOKEN_METADATA_KEY,
         test_google_iam_authorization_token},
        {GRPC_IAM_AUTHORITY_SELECTOR_METADATA_KEY,
         test_google_iam_authority_selector}
      };
      GPR_ASSERT (status == GRPC_CREDENTIALS_OK);
      GPR_ASSERT (num_md == 3);
      check_metadata (emd, md_elems, num_md);
      grpc_credentials_unref (c);
    }
    
    static void
    test_ssl_oauth2_google_iam_composite_creds (void)
    {
      grpc_closure_list closure_list = GRPC_CLOSURE_LIST_INIT;
      grpc_credentials *ssl_creds = grpc_ssl_credentials_create (test_root_cert, NULL, NULL);
      const grpc_credentials_array *creds_array;
      grpc_credentials *oauth2_creds = grpc_md_only_test_credentials_create ("Authorization", test_oauth2_bearer_token, 0);
      grpc_credentials *aux_creds = grpc_composite_credentials_create (ssl_creds, oauth2_creds, NULL);
      grpc_credentials *google_iam_creds = grpc_google_iam_credentials_create (test_google_iam_authorization_token, test_google_iam_authority_selector,
    									   NULL);
      grpc_credentials *composite_creds = grpc_composite_credentials_create (aux_creds, google_iam_creds, NULL);
      grpc_credentials_unref (ssl_creds);
      grpc_credentials_unref (oauth2_creds);
      grpc_credentials_unref (aux_creds);
      grpc_credentials_unref (google_iam_creds);
      GPR_ASSERT (strcmp (composite_creds->type, GRPC_CREDENTIALS_TYPE_COMPOSITE) == 0);
      GPR_ASSERT (grpc_credentials_has_request_metadata (composite_creds));
      GPR_ASSERT (!grpc_credentials_has_request_metadata_only (composite_creds));
      creds_array = grpc_composite_credentials_get_credentials (composite_creds);
      GPR_ASSERT (creds_array->num_creds == 3);
      GPR_ASSERT (strcmp (creds_array->creds_array[0]->type, GRPC_CREDENTIALS_TYPE_SSL) == 0);
      GPR_ASSERT (strcmp (creds_array->creds_array[1]->type, GRPC_CREDENTIALS_TYPE_OAUTH2) == 0);
      GPR_ASSERT (strcmp (creds_array->creds_array[2]->type, GRPC_CREDENTIALS_TYPE_IAM) == 0);
      grpc_credentials_get_request_metadata (composite_creds, NULL, test_service_url, check_ssl_oauth2_google_iam_composite_metadata, composite_creds, &closure_list);
      grpc_closure_list_run (&closure_list);
    }
    
    static void
    on_oauth2_creds_get_metadata_success (grpc_exec_ctx * exec_ctx, void *user_data, grpc_credentials_md * md_elems, size_t num_md, grpc_credentials_status status)
    {
      GPR_ASSERT (status == GRPC_CREDENTIALS_OK);
      GPR_ASSERT (num_md == 1);
      GPR_ASSERT (gpr_slice_str_cmp (md_elems[0].key, "Authorization") == 0);
      GPR_ASSERT (gpr_slice_str_cmp (md_elems[0].value, "Bearer ya29.AHES6ZRN3-HlhAPya30GnW_bHSb_") == 0);
      GPR_ASSERT (user_data != NULL);
      GPR_ASSERT (strcmp ((const char *) user_data, test_user_data) == 0);
    }
    
    static void
    on_oauth2_creds_get_metadata_failure (grpc_exec_ctx * exec_ctx, void *user_data, grpc_credentials_md * md_elems, size_t num_md, grpc_credentials_status status)
    {
      GPR_ASSERT (status == GRPC_CREDENTIALS_ERROR);
      GPR_ASSERT (num_md == 0);
      GPR_ASSERT (user_data != NULL);
      GPR_ASSERT (strcmp ((const char *) user_data, test_user_data) == 0);
    }
    
    static void
    validate_compute_engine_http_request (const grpc_httpcli_request * request)
    {
      GPR_ASSERT (request->handshaker != &grpc_httpcli_ssl);
      GPR_ASSERT (strcmp (request->host, "metadata") == 0);
      GPR_ASSERT (strcmp (request->path, "/computeMetadata/v1/instance/service-accounts/default/token") == 0);
      GPR_ASSERT (request->hdr_count == 1);
      GPR_ASSERT (strcmp (request->hdrs[0].key, "Metadata-Flavor") == 0);
      GPR_ASSERT (strcmp (request->hdrs[0].value, "Google") == 0);
    }
    
    static int
    compute_engine_httpcli_get_success_override (grpc_exec_ctx * exec_ctx, const grpc_httpcli_request * request, gpr_timespec deadline, grpc_httpcli_response_cb on_response, void *user_data)
    {
      grpc_httpcli_response response = http_response (200, valid_oauth2_json_response);
      validate_compute_engine_http_request (request);
      on_response (exec_ctx, user_data, &response);
      return 1;
    }
    
    static int
    compute_engine_httpcli_get_failure_override (grpc_exec_ctx * exec_ctx, const grpc_httpcli_request * request, gpr_timespec deadline, grpc_httpcli_response_cb on_response, void *user_data)
    {
      grpc_httpcli_response response = http_response (403, "Not Authorized.");
      validate_compute_engine_http_request (request);
      on_response (exec_ctx, user_data, &response);
      return 1;
    }
    
    static int
    httpcli_post_should_not_be_called (grpc_exec_ctx * exec_ctx, const grpc_httpcli_request * request, const char *body_bytes, size_t body_size, gpr_timespec deadline, grpc_httpcli_response_cb on_response, void *user_data)
    {
      GPR_ASSERT ("HTTP POST should not be called" == NULL);
      return 1;
    }
    
    static int
    httpcli_get_should_not_be_called (grpc_exec_ctx * exec_ctx, const grpc_httpcli_request * request, gpr_timespec deadline, grpc_httpcli_response_cb on_response, void *user_data)
    {
      GPR_ASSERT ("HTTP GET should not be called" == NULL);
      return 1;
    }
    
    static void
    test_compute_engine_creds_success (void)
    {
      grpc_closure_list closure_list = GRPC_CLOSURE_LIST_INIT;
      grpc_credentials *compute_engine_creds = grpc_google_compute_engine_credentials_create (NULL);
      GPR_ASSERT (grpc_credentials_has_request_metadata (compute_engine_creds));
      GPR_ASSERT (grpc_credentials_has_request_metadata_only (compute_engine_creds));
    
      /* First request: http get should be called. */
      grpc_httpcli_set_override (compute_engine_httpcli_get_success_override, httpcli_post_should_not_be_called);
      grpc_credentials_get_request_metadata (compute_engine_creds, NULL, test_service_url, on_oauth2_creds_get_metadata_success, (void *) test_user_data, &closure_list);
      grpc_closure_list_run (&closure_list);
    
      /* Second request: the cached token should be served directly. */
      grpc_httpcli_set_override (httpcli_get_should_not_be_called, httpcli_post_should_not_be_called);
      grpc_credentials_get_request_metadata (compute_engine_creds, NULL, test_service_url, on_oauth2_creds_get_metadata_success, (void *) test_user_data, &closure_list);
      grpc_closure_list_run (&closure_list);
    
      grpc_credentials_unref (compute_engine_creds);
      grpc_httpcli_set_override (NULL, NULL);
    }
    
    static void
    test_compute_engine_creds_failure (void)
    {
      grpc_closure_list closure_list = GRPC_CLOSURE_LIST_INIT;
      grpc_credentials *compute_engine_creds = grpc_google_compute_engine_credentials_create (NULL);
      grpc_httpcli_set_override (compute_engine_httpcli_get_failure_override, httpcli_post_should_not_be_called);
      GPR_ASSERT (grpc_credentials_has_request_metadata (compute_engine_creds));
      GPR_ASSERT (grpc_credentials_has_request_metadata_only (compute_engine_creds));
      grpc_credentials_get_request_metadata (compute_engine_creds, NULL, test_service_url, on_oauth2_creds_get_metadata_failure, (void *) test_user_data, &closure_list);
      grpc_credentials_unref (compute_engine_creds);
      grpc_httpcli_set_override (NULL, NULL);
      grpc_closure_list_run (&closure_list);
    }
    
    static void
    validate_refresh_token_http_request (const grpc_httpcli_request * request, const char *body, size_t body_size)
    {
      /* The content of the assertion is tested extensively in json_token_test. */
      char *expected_body = NULL;
      GPR_ASSERT (body != NULL);
      GPR_ASSERT (body_size != 0);
      gpr_asprintf (&expected_body, GRPC_REFRESH_TOKEN_POST_BODY_FORMAT_STRING, "32555999999.apps.googleusercontent.com", "EmssLNjJy1332hD4KFsecret", "1/Blahblasj424jladJDSGNf-u4Sua3HDA2ngjd42");
      GPR_ASSERT (strlen (expected_body) == body_size);
      GPR_ASSERT (memcmp (expected_body, body, body_size) == 0);
      gpr_free (expected_body);
      GPR_ASSERT (request->handshaker == &grpc_httpcli_ssl);
      GPR_ASSERT (strcmp (request->host, GRPC_GOOGLE_OAUTH2_SERVICE_HOST) == 0);
      GPR_ASSERT (strcmp (request->path, GRPC_GOOGLE_OAUTH2_SERVICE_TOKEN_PATH) == 0);
      GPR_ASSERT (request->hdr_count == 1);
      GPR_ASSERT (strcmp (request->hdrs[0].key, "Content-Type") == 0);
      GPR_ASSERT (strcmp (request->hdrs[0].value, "application/x-www-form-urlencoded") == 0);
    }
    
    static int
    refresh_token_httpcli_post_success (grpc_exec_ctx * exec_ctx, const grpc_httpcli_request * request, const char *body, size_t body_size, gpr_timespec deadline, grpc_httpcli_response_cb on_response, void *user_data)
    {
      grpc_httpcli_response response = http_response (200, valid_oauth2_json_response);
      validate_refresh_token_http_request (request, body, body_size);
      on_response (exec_ctx, user_data, &response);
      return 1;
    }
    
    static int
    refresh_token_httpcli_post_failure (grpc_exec_ctx * exec_ctx, const grpc_httpcli_request * request, const char *body, size_t body_size, gpr_timespec deadline, grpc_httpcli_response_cb on_response, void *user_data)
    {
      grpc_httpcli_response response = http_response (403, "Not Authorized.");
      validate_refresh_token_http_request (request, body, body_size);
      on_response (exec_ctx, user_data, &response);
      return 1;
    }
    
    static void
    test_refresh_token_creds_success (void)
    {
      grpc_closure_list closure_list = GRPC_CLOSURE_LIST_INIT;
      grpc_credentials *refresh_token_creds = grpc_google_refresh_token_credentials_create (test_refresh_token_str,
    											NULL);
      GPR_ASSERT (grpc_credentials_has_request_metadata (refresh_token_creds));
      GPR_ASSERT (grpc_credentials_has_request_metadata_only (refresh_token_creds));
    
      /* First request: http get should be called. */
      grpc_httpcli_set_override (httpcli_get_should_not_be_called, refresh_token_httpcli_post_success);
      grpc_credentials_get_request_metadata (refresh_token_creds, NULL, test_service_url, on_oauth2_creds_get_metadata_success, (void *) test_user_data, &closure_list);
      grpc_closure_list_run (&closure_list);
    
      /* Second request: the cached token should be served directly. */
      grpc_httpcli_set_override (httpcli_get_should_not_be_called, httpcli_post_should_not_be_called);
      grpc_credentials_get_request_metadata (refresh_token_creds, NULL, test_service_url, on_oauth2_creds_get_metadata_success, (void *) test_user_data, &closure_list);
      grpc_closure_list_run (&closure_list);
    
      grpc_credentials_unref (refresh_token_creds);
      grpc_httpcli_set_override (NULL, NULL);
      grpc_closure_list_run (&closure_list);
    }
    
    static void
    test_refresh_token_creds_failure (void)
    {
      grpc_closure_list closure_list = GRPC_CLOSURE_LIST_INIT;
      grpc_credentials *refresh_token_creds = grpc_google_refresh_token_credentials_create (test_refresh_token_str,
    											NULL);
      grpc_httpcli_set_override (httpcli_get_should_not_be_called, refresh_token_httpcli_post_failure);
      GPR_ASSERT (grpc_credentials_has_request_metadata (refresh_token_creds));
      GPR_ASSERT (grpc_credentials_has_request_metadata_only (refresh_token_creds));
      grpc_credentials_get_request_metadata (refresh_token_creds, NULL, test_service_url, on_oauth2_creds_get_metadata_failure, (void *) test_user_data, &closure_list);
      grpc_credentials_unref (refresh_token_creds);
      grpc_httpcli_set_override (NULL, NULL);
      grpc_closure_list_run (&closure_list);
    }
    
    static void
    validate_jwt_encode_and_sign_params (const grpc_auth_json_key * json_key, const char *scope, gpr_timespec token_lifetime)
    {
      GPR_ASSERT (grpc_auth_json_key_is_valid (json_key));
      GPR_ASSERT (json_key->private_key != NULL);
      GPR_ASSERT (RSA_check_key (json_key->private_key));
      GPR_ASSERT (json_key->type != NULL && strcmp (json_key->type, "service_account") == 0);
      GPR_ASSERT (json_key->private_key_id != NULL && strcmp (json_key->private_key_id, "e6b5137873db8d2ef81e06a47289e6434ec8a165") == 0);
      GPR_ASSERT (json_key->client_id != NULL && strcmp (json_key->client_id, "777-abaslkan11hlb6nmim3bpspl31ud.apps." "googleusercontent.com") == 0);
      GPR_ASSERT (json_key->client_email != NULL && strcmp (json_key->client_email, "777-abaslkan11hlb6nmim3bpspl31ud@developer." "gserviceaccount.com") == 0);
      if (scope != NULL)
        GPR_ASSERT (strcmp (scope, test_scope) == 0);
      GPR_ASSERT (!gpr_time_cmp (token_lifetime, grpc_max_auth_token_lifetime));
    }
    
    static char *
    encode_and_sign_jwt_success (const grpc_auth_json_key * json_key, const char *audience, gpr_timespec token_lifetime, const char *scope)
    {
      validate_jwt_encode_and_sign_params (json_key, scope, token_lifetime);
      return gpr_strdup (test_signed_jwt);
    }
    
    static char *
    encode_and_sign_jwt_failure (const grpc_auth_json_key * json_key, const char *audience, gpr_timespec token_lifetime, const char *scope)
    {
      validate_jwt_encode_and_sign_params (json_key, scope, token_lifetime);
      return NULL;
    }
    
    static char *
    encode_and_sign_jwt_should_not_be_called (const grpc_auth_json_key * json_key, const char *audience, gpr_timespec token_lifetime, const char *scope)
    {
      GPR_ASSERT ("grpc_jwt_encode_and_sign should not be called" == NULL);
    }
    
    static void
    on_jwt_creds_get_metadata_success (grpc_exec_ctx * exec_ctx, void *user_data, grpc_credentials_md * md_elems, size_t num_md, grpc_credentials_status status)
    {
      char *expected_md_value;
      gpr_asprintf (&expected_md_value, "Bearer %s", test_signed_jwt);
      GPR_ASSERT (status == GRPC_CREDENTIALS_OK);
      GPR_ASSERT (num_md == 1);
      GPR_ASSERT (gpr_slice_str_cmp (md_elems[0].key, "Authorization") == 0);
      GPR_ASSERT (gpr_slice_str_cmp (md_elems[0].value, expected_md_value) == 0);
      GPR_ASSERT (user_data != NULL);
      GPR_ASSERT (strcmp ((const char *) user_data, test_user_data) == 0);
      gpr_free (expected_md_value);
    }
    
    static void
    on_jwt_creds_get_metadata_failure (grpc_exec_ctx * exec_ctx, void *user_data, grpc_credentials_md * md_elems, size_t num_md, grpc_credentials_status status)
    {
      GPR_ASSERT (status == GRPC_CREDENTIALS_ERROR);
      GPR_ASSERT (num_md == 0);
      GPR_ASSERT (user_data != NULL);
      GPR_ASSERT (strcmp ((const char *) user_data, test_user_data) == 0);
    }
    
    static void
    test_jwt_creds_success (void)
    {
      char *json_key_string = test_json_key_str ();
      grpc_closure_list closure_list = GRPC_CLOSURE_LIST_INIT;
      grpc_credentials *jwt_creds = grpc_service_account_jwt_access_credentials_create (json_key_string, grpc_max_auth_token_lifetime, NULL);
      GPR_ASSERT (grpc_credentials_has_request_metadata (jwt_creds));
      GPR_ASSERT (grpc_credentials_has_request_metadata_only (jwt_creds));
    
      /* First request: jwt_encode_and_sign should be called. */
      grpc_jwt_encode_and_sign_set_override (encode_and_sign_jwt_success);
      grpc_credentials_get_request_metadata (jwt_creds, NULL, test_service_url, on_jwt_creds_get_metadata_success, (void *) test_user_data, &closure_list);
      grpc_closure_list_run (&closure_list);
    
      /* Second request: the cached token should be served directly. */
      grpc_jwt_encode_and_sign_set_override (encode_and_sign_jwt_should_not_be_called);
      grpc_credentials_get_request_metadata (jwt_creds, NULL, test_service_url, on_jwt_creds_get_metadata_success, (void *) test_user_data, &closure_list);
      grpc_closure_list_run (&closure_list);
    
      /* Third request: Different service url so jwt_encode_and_sign should be
         called again (no caching). */
      grpc_jwt_encode_and_sign_set_override (encode_and_sign_jwt_success);
      grpc_credentials_get_request_metadata (jwt_creds, NULL, other_test_service_url, on_jwt_creds_get_metadata_success, (void *) test_user_data, &closure_list);
      grpc_closure_list_run (&closure_list);
    
      gpr_free (json_key_string);
      grpc_credentials_unref (jwt_creds);
      grpc_jwt_encode_and_sign_set_override (NULL);
    }
    
    static void
    test_jwt_creds_signing_failure (void)
    {
      char *json_key_string = test_json_key_str ();
      grpc_closure_list closure_list = GRPC_CLOSURE_LIST_INIT;
      grpc_credentials *jwt_creds = grpc_service_account_jwt_access_credentials_create (json_key_string, grpc_max_auth_token_lifetime, NULL);
      GPR_ASSERT (grpc_credentials_has_request_metadata (jwt_creds));
      GPR_ASSERT (grpc_credentials_has_request_metadata_only (jwt_creds));
    
      grpc_jwt_encode_and_sign_set_override (encode_and_sign_jwt_failure);
      grpc_credentials_get_request_metadata (jwt_creds, NULL, test_service_url, on_jwt_creds_get_metadata_failure, (void *) test_user_data, &closure_list);
    
      gpr_free (json_key_string);
      grpc_credentials_unref (jwt_creds);
      grpc_jwt_encode_and_sign_set_override (NULL);
      grpc_closure_list_run (&closure_list);
    }
    
    static void
    set_google_default_creds_env_var_with_file_contents (const char *file_prefix, const char *contents)
    {
      size_t contents_len = strlen (contents);
      char *creds_file_name;
      FILE *creds_file = gpr_tmpfile (file_prefix, &creds_file_name);
      GPR_ASSERT (creds_file_name != NULL);
      GPR_ASSERT (creds_file != NULL);
      GPR_ASSERT (fwrite (contents, 1, contents_len, creds_file) == contents_len);
      fclose (creds_file);
      gpr_setenv (GRPC_GOOGLE_CREDENTIALS_ENV_VAR, creds_file_name);
      gpr_free (creds_file_name);
    }
    
    static grpc_credentials *
    composite_inner_creds (grpc_credentials * creds, const char *inner_creds_type)
    {
      size_t i;
      grpc_composite_credentials *composite;
      GPR_ASSERT (strcmp (creds->type, GRPC_CREDENTIALS_TYPE_COMPOSITE) == 0);
      composite = (grpc_composite_credentials *) creds;
      for (i = 0; i < composite->inner.num_creds; i++)
        {
          grpc_credentials *c = composite->inner.creds_array[i];
          if (strcmp (c->type, inner_creds_type) == 0)
    	return c;
        }
      GPR_ASSERT (0);		/* Not found. */
    }
    
    static void
    test_google_default_creds_auth_key (void)
    {
      grpc_service_account_jwt_access_credentials *jwt;
      grpc_credentials *creds;
      char *json_key = test_json_key_str ();
      grpc_flush_cached_google_default_credentials ();
      set_google_default_creds_env_var_with_file_contents ("json_key_google_default_creds", json_key);
      gpr_free (json_key);
      creds = grpc_google_default_credentials_create ();
      GPR_ASSERT (creds != NULL);
      jwt = (grpc_service_account_jwt_access_credentials *) composite_inner_creds (creds, GRPC_CREDENTIALS_TYPE_JWT);
      GPR_ASSERT (strcmp (jwt->key.client_id, "777-abaslkan11hlb6nmim3bpspl31ud.apps.googleusercontent.com") == 0);
      grpc_credentials_unref (creds);
      gpr_setenv (GRPC_GOOGLE_CREDENTIALS_ENV_VAR, "");	/* Reset. */
    }
    
    static void
    test_google_default_creds_access_token (void)
    {
      grpc_google_refresh_token_credentials *refresh;
      grpc_credentials *creds;
      grpc_flush_cached_google_default_credentials ();
      set_google_default_creds_env_var_with_file_contents ("refresh_token_google_default_creds", test_refresh_token_str);
      creds = grpc_google_default_credentials_create ();
      GPR_ASSERT (creds != NULL);
      refresh = (grpc_google_refresh_token_credentials *) composite_inner_creds (creds, GRPC_CREDENTIALS_TYPE_OAUTH2);
      GPR_ASSERT (strcmp (refresh->refresh_token.client_id, "32555999999.apps.googleusercontent.com") == 0);
      grpc_credentials_unref (creds);
      gpr_setenv (GRPC_GOOGLE_CREDENTIALS_ENV_VAR, "");	/* Reset. */
    }
    
    typedef enum
    {
      PLUGIN_INITIAL_STATE,
      PLUGIN_GET_METADATA_CALLED_STATE,
      PLUGIN_DESTROY_CALLED_STATE
    } plugin_state;
    
    typedef struct
    {
      const char *key;
      const char *value;
    } plugin_metadata;
    
    static const plugin_metadata plugin_md[] = { {"foo", "bar"}, {"hi", "there"} };
    
    static void
    plugin_get_metadata_success (void *state, const char *service_url, grpc_credentials_plugin_metadata_cb cb, void *user_data)
    {
      size_t i;
      grpc_metadata md[GPR_ARRAY_SIZE (plugin_md)];
      plugin_state *s = (plugin_state *) state;
      GPR_ASSERT (strcmp (service_url, test_service_url) == 0);
      *s = PLUGIN_GET_METADATA_CALLED_STATE;
      for (i = 0; i < GPR_ARRAY_SIZE (plugin_md); i++)
        {
          memset (&md[i], 0, sizeof (grpc_metadata));
          md[i].key = plugin_md[i].key;
          md[i].value = plugin_md[i].value;
          md[i].value_length = strlen (plugin_md[i].value);
        }
      cb (user_data, md, GPR_ARRAY_SIZE (md), GRPC_STATUS_OK, NULL);
    }
    
    static void
    plugin_get_metadata_failure (void *state, const char *service_url, grpc_credentials_plugin_metadata_cb cb, void *user_data)
    {
      plugin_state *s = (plugin_state *) state;
      GPR_ASSERT (strcmp (service_url, test_service_url) == 0);
      *s = PLUGIN_GET_METADATA_CALLED_STATE;
      cb (user_data, NULL, 0, GRPC_STATUS_UNAUTHENTICATED, "Could not get metadata for plugin.");
    }
    
    static void
    on_plugin_metadata_received_success (grpc_exec_ctx * exec_ctx, void *user_data, grpc_credentials_md * md_elems, size_t num_md, grpc_credentials_status status)
    {
      size_t i = 0;
      GPR_ASSERT (user_data == NULL);
      GPR_ASSERT (md_elems != NULL);
      GPR_ASSERT (num_md == GPR_ARRAY_SIZE (plugin_md));
      for (i = 0; i < num_md; i++)
        {
          GPR_ASSERT (gpr_slice_str_cmp (md_elems[i].key, plugin_md[i].key) == 0);
          GPR_ASSERT (gpr_slice_str_cmp (md_elems[i].value, plugin_md[i].value) == 0);
        }
    }
    
    static void
    on_plugin_metadata_received_failure (grpc_exec_ctx * exec_ctx, void *user_data, grpc_credentials_md * md_elems, size_t num_md, grpc_credentials_status status)
    {
      GPR_ASSERT (user_data == NULL);
      GPR_ASSERT (md_elems == NULL);
      GPR_ASSERT (num_md == 0);
      GPR_ASSERT (status == GRPC_CREDENTIALS_ERROR);
    }
    
    static void
    plugin_destroy (void *state)
    {
      plugin_state *s = (plugin_state *) state;
      *s = PLUGIN_DESTROY_CALLED_STATE;
    }
    
    static void
    test_metadata_plugin_success (void)
    {
      grpc_credentials *creds;
      plugin_state state = PLUGIN_INITIAL_STATE;
      grpc_metadata_credentials_plugin plugin;
      grpc_closure_list closure_list = GRPC_CLOSURE_LIST_INIT;
    
      plugin.state = &state;
      plugin.get_metadata = plugin_get_metadata_success;
      plugin.destroy = plugin_destroy;
    
      creds = grpc_metadata_credentials_create_from_plugin (plugin, NULL);
      GPR_ASSERT (state == PLUGIN_INITIAL_STATE);
      grpc_credentials_get_request_metadata (creds, NULL, test_service_url, on_plugin_metadata_received_success, NULL, &closure_list);
      GPR_ASSERT (state == PLUGIN_GET_METADATA_CALLED_STATE);
      grpc_credentials_release (creds);
      GPR_ASSERT (state == PLUGIN_DESTROY_CALLED_STATE);
      grpc_closure_list_run (&closure_list);
    }
    
    static void
    test_metadata_plugin_failure (void)
    {
      grpc_credentials *creds;
      plugin_state state = PLUGIN_INITIAL_STATE;
      grpc_metadata_credentials_plugin plugin;
      grpc_closure_list closure_list = GRPC_CLOSURE_LIST_INIT;
    
      plugin.state = &state;
      plugin.get_metadata = plugin_get_metadata_failure;
      plugin.destroy = plugin_destroy;
    
      creds = grpc_metadata_credentials_create_from_plugin (plugin, NULL);
      GPR_ASSERT (state == PLUGIN_INITIAL_STATE);
      grpc_credentials_get_request_metadata (creds, NULL, test_service_url, on_plugin_metadata_received_failure, NULL, &closure_list);
      GPR_ASSERT (state == PLUGIN_GET_METADATA_CALLED_STATE);
      grpc_credentials_release (creds);
      GPR_ASSERT (state == PLUGIN_DESTROY_CALLED_STATE);
      grpc_closure_list_run (&closure_list);
    }
    
    int
    main (int argc, char **argv)
    {
      grpc_test_init (argc, argv);
      test_empty_md_store ();
      test_ref_unref_empty_md_store ();
      test_add_to_empty_md_store ();
      test_add_cstrings_to_empty_md_store ();
      test_empty_preallocated_md_store ();
      test_add_abunch_to_md_store ();
      test_oauth2_token_fetcher_creds_parsing_ok ();
      test_oauth2_token_fetcher_creds_parsing_bad_http_status ();
      test_oauth2_token_fetcher_creds_parsing_empty_http_body ();
      test_oauth2_token_fetcher_creds_parsing_invalid_json ();
      test_oauth2_token_fetcher_creds_parsing_missing_token ();
      test_oauth2_token_fetcher_creds_parsing_missing_token_type ();
      test_oauth2_token_fetcher_creds_parsing_missing_token_lifetime ();
      test_google_iam_creds ();
      test_access_token_creds ();
      test_ssl_oauth2_composite_creds ();
      test_ssl_oauth2_google_iam_composite_creds ();
      test_compute_engine_creds_success ();
      test_compute_engine_creds_failure ();
      test_refresh_token_creds_success ();
      test_refresh_token_creds_failure ();
      test_jwt_creds_success ();
      test_jwt_creds_signing_failure ();
      test_google_default_creds_auth_key ();
      test_google_default_creds_access_token ();
      test_metadata_plugin_success ();
      test_metadata_plugin_failure ();
      return 0;
    }