/**
 * Tests authorization special cases with views. These are special exceptions that prohibit certain
 * operations on views even if the user has an explicit privilege on that view.
 * @tags: [requires_sharding]
 */
(function() {
"use strict";

// Multiple users cannot be authenticated on one connection within a session.
TestData.disableImplicitSessions = true;

function runTest(conn) {
    // Create the admin user.
    const adminDB = conn.getDB("admin");
    assert.commandWorked(adminDB.runCommand({createUser: "admin", pwd: "admin", roles: ["root"]}));
    assert(adminDB.auth("admin", "admin"));

    const viewsDBName = "views_authz";
    const viewsDB = adminDB.getSiblingDB(viewsDBName);
    viewsDB.dropAllUsers();
    viewsDB.logout();

    // Create a user who can read, create and modify a view 'view' and a read a namespace
    // 'permitted' but does not have access to 'forbidden'.
    assert.commandWorked(viewsDB.runCommand({
        createRole: "readWriteView",
        privileges: [
            {
                resource: {db: viewsDBName, collection: "view"},
                actions: ["find", "createCollection", "collMod"]
            },
            {resource: {db: viewsDBName, collection: "view2"}, actions: ["find"]},
            {resource: {db: viewsDBName, collection: "permitted"}, actions: ["find"]}
        ],
        roles: []
    }));
    assert.commandWorked(
        viewsDB.runCommand({createUser: "viewUser", pwd: "pwd", roles: ["readWriteView"]}));

    adminDB.logout();
    assert(viewsDB.auth("viewUser", "pwd"));

    const lookupStage = {$lookup: {from: "forbidden", localField: "x", foreignField: "x", as: "y"}};
    const graphLookupStage = {
        $graphLookup:
            {from: "forbidden", startWith: [], connectFromField: "x", connectToField: "x", as: "y"}
    };

    // You cannot create a view if you have both the 'createCollection' and 'find' actions on
    // that view but not the 'find' action on all of the dependent namespaces.
    assert.commandFailedWithCode(viewsDB.createView("view", "forbidden", []),
                                 ErrorCodes.Unauthorized,
                                 "created a readable view on an unreadable collection");
    assert.commandFailedWithCode(viewsDB.createView("view", "permitted", [lookupStage]),
                                 ErrorCodes.Unauthorized,
                                 "created a readable view on an unreadable collection via $lookup");
    assert.commandFailedWithCode(
        viewsDB.createView("view", "permitted", [graphLookupStage]),
        ErrorCodes.Unauthorized,
        "created a readable view on an unreadable collection via $graphLookup");
    assert.commandFailedWithCode(
        viewsDB.createView("view", "permitted", [{$facet: {a: [lookupStage]}}]),
        ErrorCodes.Unauthorized,
        "created a readable view on an unreadable collection via $lookup in a $facet");
    assert.commandFailedWithCode(
        viewsDB.createView("view", "permitted", [{$facet: {b: [graphLookupStage]}}]),
        ErrorCodes.Unauthorized,
        "created a readable view on an unreadable collection via $graphLookup in a $facet");

    assert.commandWorked(viewsDB.createView("view", "permitted", [{$match: {x: 1}}]));

    // You cannot modify a view if you have both the 'collMod' and 'find' actions on that view
    // but not the 'find' action on all of the dependent namespaces.
    assert.commandFailedWithCode(
        viewsDB.runCommand({collMod: "view", viewOn: "forbidden", pipeline: [{$match: {}}]}),
        ErrorCodes.Unauthorized,
        "modified a view to read an unreadable collection");
    assert.commandFailedWithCode(
        viewsDB.runCommand({collMod: "view", viewOn: "permitted", pipeline: [lookupStage]}),
        ErrorCodes.Unauthorized,
        "modified a view to read an unreadable collection via $lookup");
    assert.commandFailedWithCode(
        viewsDB.runCommand({collMod: "view", viewOn: "permitted", pipeline: [graphLookupStage]}),
        ErrorCodes.Unauthorized,
        "modified a view to read an unreadable collection via $graphLookup");
    assert.commandFailedWithCode(
        viewsDB.runCommand(
            {collMod: "view", viewOn: "permitted", pipeline: [{$facet: {a: [lookupStage]}}]}),
        ErrorCodes.Unauthorized,
        "modified a view to read an unreadable collection via $lookup in a $facet");
    assert.commandFailedWithCode(
        viewsDB.runCommand(
            {collMod: "view", viewOn: "permitted", pipeline: [{$facet: {b: [graphLookupStage]}}]}),
        ErrorCodes.Unauthorized,
        "modified a view to read an unreadable collection via $graphLookup in a $facet");

    // When auth is enabled, users must specify both "viewOn" and "pipeline" when running
    // collMod on a view; specifying only one or the other is not allowed. Without both the
    // "viewOn" and "pipeline" specified, authorization checks cannot determine if the users
    // have the necessary privileges.
    assert.commandFailedWithCode(viewsDB.runCommand({collMod: "view", pipeline: []}),
                                 ErrorCodes.InvalidOptions,
                                 "modified a view without having to specify 'viewOn'");
    assert.commandFailedWithCode(viewsDB.runCommand({collMod: "view", viewOn: "other"}),
                                 ErrorCodes.InvalidOptions,
                                 "modified a view without having to specify 'pipeline'");
    viewsDB.logout();

    // Create a view on a forbidden collection and populate it.
    assert.eq(1, adminDB.auth("admin", "admin"));
    assert.commandWorked(viewsDB.createView("view2", "forbidden", []));
    for (let i = 0; i < 10; i++) {
        assert.commandWorked(viewsDB.forbidden.insert({x: 1}));
    }
    adminDB.logout();

    // Performing a find on a readable view returns a cursor that allows us to perform a getMore
    // even if the underlying collection is unreadable.
    assert(viewsDB.auth("viewUser", "pwd"));
    assert.commandFailedWithCode(viewsDB.runCommand({find: "forbidden"}),
                                 ErrorCodes.Unauthorized,
                                 "successfully performed a find on an unreadable namespace");
    const res = viewsDB.runCommand({find: "view2", batchSize: 1});
    assert.commandWorked(res, "could not perform a find on a readable view");
    assert.eq(res.cursor.ns,
              "views_authz.view2",
              "performing find on a view does not return a cursor on the view namespace");
    assert.commandWorked(viewsDB.runCommand({getMore: res.cursor.id, collection: "view2"}),
                         "could not perform getMore on a readable view");
    viewsDB.logout();
}

// Run the test on a standalone.
const mongod = MongoRunner.runMongod({auth: "", bind_ip: "127.0.0.1"});
runTest(mongod);
MongoRunner.stopMongod(mongod);

// Run the test on a sharded cluster.
const cluster = new ShardingTest(
    {shards: 1, mongos: 1, keyFile: "jstests/libs/key1", other: {shardOptions: {auth: ""}}});
runTest(cluster);
cluster.stop();
}());