test-mongocrypt-key-cache.c

/*
 * Copyright 2019-present MongoDB, Inc.
 *
 * 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 "mongocrypt-cache-key-private.h"
#include "mongocrypt-crypto-private.h"
#include "mongocrypt.h"
#include "test-mongocrypt-assert-match-bson.h"
#include "test-mongocrypt.h"

typedef struct {
    _mongocrypt_buffer_t bson;
    _mongocrypt_key_doc_t *parsed;
    _mongocrypt_buffer_t kms_reply;
    _mongocrypt_buffer_t uuid;
    _mongocrypt_buffer_t marking;
} gen_key_t;

/* The JSON spec tests refer to key ids by a shorthand integer.
 * This function maps that integer to a UUID buffer. */
static void lookup_key_id(uint32_t index, _mongocrypt_buffer_t *buf) {
    const char *key_ids[] = {"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA",
                             "BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB",
                             "CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC"};

    BSON_ASSERT(index < 3);
    _mongocrypt_buffer_copy_from_hex(buf, key_ids[index]);
    buf->subtype = BSON_SUBTYPE_UUID;
    BSON_ASSERT(_mongocrypt_buffer_is_uuid(buf));
}

/* Generate a realistic key document given a @key_description, which contains an
 * _id
 * and possible keyAltNames. key_out and key_doc_out are NULLable outputs. */
static void
gen_key(_mongocrypt_tester_t *tester, bson_t *key_description, bson_t *key_out, _mongocrypt_key_doc_t *key_doc_out) {
    bson_iter_t iter;
    _mongocrypt_buffer_t key_material;
    _mongocrypt_buffer_t key_id;
    bson_t key, masterkey;
    bool local_kms;

    bson_init(&key);
    BSON_APPEND_INT32(&key, "status", 1);
    BSON_APPEND_DATE_TIME(&key, "updateDate", 1234567890);
    BSON_APPEND_DATE_TIME(&key, "creationDate", 1234567890);
    BSON_APPEND_DOCUMENT_BEGIN(&key, "masterKey", &masterkey);

    local_kms = bson_iter_init_find(&iter, key_description, "local") && bson_iter_as_bool(&iter);

    if (local_kms) {
        BSON_APPEND_UTF8(&masterkey, "provider", "local");
    } else {
        BSON_APPEND_UTF8(&masterkey, "provider", "aws");
        BSON_APPEND_UTF8(&masterkey, "region", "us-east-1");
        BSON_APPEND_UTF8(&masterkey,
                         "key",
                         "arn:aws:kms:us-east-1:579766882180:key/"
                         "89fcc2c4-08b0-4bd9-9f25-e30687b580d0");
    }
    bson_append_document_end(&key, &masterkey);

    BSON_ASSERT(bson_iter_init_find(&iter, key_description, "_id"));
    lookup_key_id(bson_iter_int32(&iter), &key_id);
    BSON_ASSERT(_mongocrypt_buffer_append(&key_id, &key, "_id", 3));

    if (bson_iter_init_find(&iter, key_description, "keyAltNames")) {
        bson_t key_alt_name_bson;
        int counter = 0;

        BSON_APPEND_ARRAY_BEGIN(&key, "keyAltNames", &key_alt_name_bson);
        for (bson_iter_recurse(&iter, &iter); bson_iter_next(&iter);) {
            char *field;

            field = bson_strdup_printf("%d", counter);
            BSON_APPEND_UTF8(&key_alt_name_bson, field, bson_iter_utf8(&iter, NULL));
            counter++;
            bson_free(field);
        }
        bson_append_array_end(&key, &key_alt_name_bson);
    }

    /* Append a keyMaterial that is decryptable by the local KMS masterkey. For
     * AWS it gets ignored since it is dictated by KMS response. */
    _mongocrypt_buffer_copy_from_hex(&key_material,
                                     "75bdbbaec862a8ae09aa16f6c67c0ae117dd15bf49b8a7947bac6de5a"
                                     "610178a3adad4bbe5bec1e30c55378f7d80d0fd5152d46e954aa32528"
                                     "69901e03cf7938434fdf7e5bf27f0ec1c85c4c5a92e38b7e3f7ce686d"
                                     "7985102c85905da220a27ee01202de25b6831e64974baffb35b7c30c5"
                                     "941dfb37b04fff6871d7208e4cde8d1bff0cd69a70dcb613dc27cfe84"
                                     "7d7544b6d0d8b4f6c9a5b6fb9c1565c43ef");
    key_material.subtype = BSON_SUBTYPE_BINARY;
    BSON_ASSERT(_mongocrypt_buffer_append(&key_material, &key, "keyMaterial", -1));

    if (key_out) {
        bson_copy_to(&key, key_out);
    }

    if (key_doc_out) {
        mongocrypt_status_t *status;

        status = mongocrypt_status_new();
        ASSERT_OK_STATUS(_mongocrypt_key_parse_owned(&key, key_doc_out, status), status);
        mongocrypt_status_destroy(status);
    }

    bson_destroy(&key);
    _mongocrypt_buffer_cleanup(&key_id);
    _mongocrypt_buffer_cleanup(&key_material);
}

/* Append a realistic subtype 6 marking to a BSON document given a description
 * of the requested key, which may contain either an _id or single keyAltName.
 */
static void _append_marking(bson_t *appendee, const char *key, const bson_t *request) {
    /* Create a marking with a fixed value "v": 1 */
    bson_t marking_bson;
    _mongocrypt_buffer_t marking_buf;
    bson_iter_t iter;

    bson_init(&marking_bson);

    if (bson_iter_init_find(&iter, request, "_id")) {
        _mongocrypt_buffer_t key_id;

        lookup_key_id(bson_iter_int32(&iter), &key_id);
        BSON_ASSERT(_mongocrypt_buffer_append(&key_id, &marking_bson, "ki", 2));
        _mongocrypt_buffer_cleanup(&key_id);
    } else {
        /* If no _id, then keyAltName must be specified. */
        BSON_ASSERT(bson_iter_init_find(&iter, request, "keyAltName"));
        BSON_APPEND_UTF8(&marking_bson, "ka", bson_iter_utf8(&iter, NULL));
    }

    /* Append an arbitrary value and algorithm. It won't be checked in the tests.
     */
    BSON_APPEND_INT32(&marking_bson, "v", 123);
    BSON_APPEND_INT32(&marking_bson, "a", MONGOCRYPT_ENCRYPTION_ALGORITHM_DETERMINISTIC);

    /* Append the prefix 0 byte, per the marking binary format. */
    _mongocrypt_buffer_init(&marking_buf);
    _mongocrypt_buffer_resize(&marking_buf, marking_bson.len + 1);
    marking_buf.data[0] = 0;
    memcpy(marking_buf.data + 1, bson_get_data(&marking_bson), marking_bson.len);
    marking_buf.subtype = 6;
    BSON_ASSERT(_mongocrypt_buffer_append(&marking_buf, appendee, key, -1));

    bson_destroy(&marking_bson);
    _mongocrypt_buffer_cleanup(&marking_buf);
}

/* Manually add a cache entry given a description (_id and possible keyAltNames)
 */
static void _add_to_cache(_mongocrypt_tester_t *tester, mongocrypt_ctx_t *ctx, bson_t *cache_entry) {
    bson_iter_t iter;
    _mongocrypt_buffer_t key_id;
    _mongocrypt_key_alt_name_t *key_alt_names = NULL;
    _mongocrypt_cache_key_attr_t *cache_key_attr;
    _mongocrypt_cache_key_value_t *cache_key_value;
    _mongocrypt_key_doc_t *key_doc;
    _mongocrypt_buffer_t key_material_placeholder;
    mongocrypt_status_t *status;

    status = mongocrypt_status_new();
    BSON_ASSERT(bson_iter_init_find(&iter, cache_entry, "_id"));
    lookup_key_id(bson_iter_int32(&iter), &key_id);

    if (bson_iter_init_find(&iter, cache_entry, "keyAltNames")) {
        ASSERT_OK_STATUS(_mongocrypt_key_alt_name_from_iter(&iter, &key_alt_names, status), status);
    }

    cache_key_attr = _mongocrypt_cache_key_attr_new(&key_id, key_alt_names);
    /* TODO: consider improving these tests by identifying the decrypted and
     * encrypted key material. That is a little tricky, since it will require
     * parsing the KMS request to know which decrypted key material to respond
     * with. */
    _mongocrypt_buffer_init(&key_material_placeholder);
    _mongocrypt_buffer_resize(&key_material_placeholder, MONGOCRYPT_KEY_LEN);
    memset(key_material_placeholder.data, 0, MONGOCRYPT_KEY_LEN);

    key_doc = _mongocrypt_key_new();
    gen_key(tester, cache_entry, NULL, key_doc);

    cache_key_value = _mongocrypt_cache_key_value_new(key_doc, &key_material_placeholder);

    ASSERT_OK_STATUS(_mongocrypt_cache_add_copy(&ctx->crypt->cache_key, cache_key_attr, cache_key_value, status),
                     status);

    _mongocrypt_key_destroy(key_doc);
    _mongocrypt_buffer_cleanup(&key_material_placeholder);
    _mongocrypt_cache_key_attr_destroy(cache_key_attr);
    _mongocrypt_cache_key_value_destroy(cache_key_value);
    _mongocrypt_key_alt_name_destroy_all(key_alt_names);
    _mongocrypt_buffer_cleanup(&key_id);
    mongocrypt_status_destroy(status);
}

/* Match a single cache entry against an expectation document (containing _id
 * and
 * possible list of keyAltNames)
 */
static bool _match_one_cache_entry(_mongocrypt_cache_pair_t *pair, bson_t *expected_entry) {
    bson_iter_t iter;
    _mongocrypt_buffer_t key_id;
    _mongocrypt_key_alt_name_t *key_alt_names = NULL;
    _mongocrypt_cache_key_attr_t *attr;
    mongocrypt_status_t *status;
    bool matched = false;

    _mongocrypt_buffer_init(&key_id);
    attr = pair->attr;
    status = mongocrypt_status_new();

    bson_iter_init_find(&iter, expected_entry, "_id");
    lookup_key_id(bson_iter_int32(&iter), &key_id);
    if (0 != _mongocrypt_buffer_cmp(&key_id, &attr->id)) {
        goto done;
    }

    if (bson_iter_init_find(&iter, expected_entry, "keyAltNames")) {
        ASSERT_OK_STATUS(_mongocrypt_key_alt_name_from_iter(&iter, &key_alt_names, status), status);
    }

    if (!_mongocrypt_key_alt_name_unique_list_equal(key_alt_names, attr->alt_names)) {
        TEST_PRINTF("failed to match key alt names\n");
        goto done;
    }

    matched = true;

done:
    _mongocrypt_buffer_cleanup(&key_id);
    _mongocrypt_key_alt_name_destroy_all(key_alt_names);
    mongocrypt_status_destroy(status);
    return matched;
}

/* Find exactly one cache entry matching expected_entry.
 * TODO: Instead of reaching inside the cache to make these checks, I think a
 * better approach would be to have the cache dump as BSON, then check
 * against that BSON with bson matching functions. Right now, if/when we modify
 * the cache structure, we'll need to update this test logic.
 * Alternatively, another solution would be to move part of this logic inside
 * the key cache and call it from the test.  Maybe then the method would look
 * like a "count" method instead of a "return true iff there is a single match"
 * method.  We could also use a "count" method to assert no matches, etc.
 */
static void _match_cache_entry(_mongocrypt_tester_t *tester, mongocrypt_ctx_t *ctx, bson_t *expected_entry) {
    _mongocrypt_cache_pair_t *pair;
    bool matched = false;

    pair = ctx->crypt->cache_key.pair;

    while (pair) {
        if (_match_one_cache_entry(pair, expected_entry)) {
            if (matched) {
                TEST_PRINTF("double matched entry: %s\n", bson_as_relaxed_extended_json(expected_entry, NULL));
                BSON_ASSERT(false);
            }
            matched = true;
        }

        pair = pair->next;
    }

    if (!matched) {
        TEST_PRINTF("could not match entry: %s\n", bson_as_relaxed_extended_json(expected_entry, NULL));
        BSON_ASSERT(false);
    }
}

static void _run_one_test(_mongocrypt_tester_t *tester, mongocrypt_ctx_t *ctx, bson_t *test) {
    bson_iter_t iter;
    bson_t mongocryptd_reply, tmp;
    _mongocrypt_buffer_t buf;
    int32_t counter;
    mongocrypt_status_t *status;

    if (bson_iter_init_find(&iter, test, "description")) {
        TEST_PRINTF("- %s\n", bson_iter_utf8(&iter, NULL));
    }

    if (bson_iter_init_find(&iter, test, "skipReason")) {
        TEST_PRINTF("  - skipping: %s\n", bson_iter_utf8(&iter, NULL));
        return;
    }

    status = mongocrypt_status_new();

    /* Set up cache */
    if (bson_iter_init_find(&iter, test, "cached")) {
        for (bson_iter_recurse(&iter, &iter); bson_iter_next(&iter);) {
            bson_t cache_entry;

            bson_iter_bson(&iter, &cache_entry);
            _add_to_cache(tester, ctx, &cache_entry);
        }
    }

    /* Supply the requests for keys through the mongocryptd reply */
    BSON_ASSERT(bson_iter_init_find(&iter, test, "requests"));
    counter = 0;
    bson_init(&mongocryptd_reply);
    BSON_APPEND_DOCUMENT_BEGIN(&mongocryptd_reply, "result", &tmp);
    for (bson_iter_recurse(&iter, &iter); bson_iter_next(&iter);) {
        bson_t request;
        char *field;

        bson_iter_bson(&iter, &request);
        field = bson_strdup_printf("%d", counter);
        _append_marking(&tmp, field, &request);
        bson_free(field);
        counter++;
    }
    bson_append_document_end(&mongocryptd_reply, &tmp);

    _mongocrypt_tester_run_ctx_to(tester, ctx, MONGOCRYPT_CTX_NEED_MONGO_MARKINGS);
    _mongocrypt_buffer_from_bson(&buf, &mongocryptd_reply);
    ASSERT_OK(mongocrypt_ctx_mongo_feed(ctx, _mongocrypt_buffer_as_binary(&buf)), ctx);
    BSON_ASSERT(mongocrypt_ctx_mongo_done(ctx));

    /* If we're expected to supply keys back, do so. */
    if (bson_iter_init_find(&iter, test, "replies")) {
        BSON_ASSERT(mongocrypt_ctx_state(ctx) == MONGOCRYPT_CTX_NEED_MONGO_KEYS);

        for (bson_iter_recurse(&iter, &iter); bson_iter_next(&iter);) {
            bson_t key;
            bson_t key_description;

            bson_iter_bson(&iter, &key_description);
            gen_key(tester, &key_description, &key, NULL);
            _mongocrypt_buffer_from_bson(&buf, &key);
            /* If expectations expect failure, fall through. */
            if (!mongocrypt_ctx_mongo_feed(ctx, _mongocrypt_buffer_as_binary(&buf))) {
                bson_destroy(&key);
                break;
            }
            bson_destroy(&key);
        }

        /* We might have failed at this point. If so, do not continue so we keep
         * original error message. */
        if (mongocrypt_ctx_status(ctx, status)) {
            (void)mongocrypt_ctx_mongo_done(ctx);
        }
    }

    /* Check expectations */
    if (bson_iter_init_find(&iter, test, "expect")) {
        bson_t expectations;

        mongocrypt_ctx_status(ctx, status);
        bson_iter_bson(&iter, &expectations);
        if (bson_iter_init_find(&iter, &expectations, "errmsg")) {
            _mongocrypt_tester_run_ctx_to(tester, ctx, MONGOCRYPT_CTX_ERROR);
            ASSERT_FAILS_STATUS(mongocrypt_status_ok(status), status, bson_iter_utf8(&iter, NULL));
        } else {
            _mongocrypt_tester_run_ctx_to(tester, ctx, MONGOCRYPT_CTX_DONE);
            ASSERT_OK_STATUS(mongocrypt_status_ok(status), status);
        }

        if (bson_iter_init_find(&iter, &expectations, "cached")) {
            uint32_t count = 0;

            for (bson_iter_recurse(&iter, &iter); bson_iter_next(&iter);) {
                bson_t entry_description;

                bson_iter_bson(&iter, &entry_description);
                _match_cache_entry(tester, ctx, &entry_description);

                count++;
            }
            BSON_ASSERT(count == _mongocrypt_cache_num_entries(&ctx->crypt->cache_key));
        }
    }

    bson_destroy(&mongocryptd_reply);
    mongocrypt_status_destroy(status);
}

/* Run declarative JSON tests, like driver spec tests. */
static void _test_key_cache(_mongocrypt_tester_t *tester) {
    mongocrypt_t *crypt;
    mongocrypt_ctx_t *ctx;
    bson_t test_file;
    bson_iter_t iter;

    _load_json_as_bson("./test/data/cache-tests.json", &test_file);
    for (bson_iter_init(&iter, &test_file); bson_iter_next(&iter);) {
        bson_t test;
        crypt = _mongocrypt_tester_mongocrypt(TESTER_MONGOCRYPT_DEFAULT);
        ctx = mongocrypt_ctx_new(crypt);

        bson_iter_bson(&iter, &test);

        BSON_ASSERT(mongocrypt_ctx_encrypt_init(ctx, "test", -1, TEST_BSON("{'insert': 'test'}")));
        _run_one_test(tester, ctx, &test);
        bson_destroy(&test);

        mongocrypt_ctx_destroy(ctx);
        mongocrypt_destroy(crypt);
    }
    bson_destroy(&test_file);
}

void _mongocrypt_tester_install_key_cache(_mongocrypt_tester_t *tester) {
    INSTALL_TEST(_test_key_cache);
}