From MSDN: Application Roles on MSDN
An application role is a database principal that enables an application to run with its own, user-like permissions. You can use application roles to enable access to specific data to only those users who connect through a particular application. Unlike database roles, application roles contain no members and are inactive by default. Application roles work with both authentication modes. Application roles are enabled by using sp_setapprole, which requires a password. Because application roles are a database-level principal, they can access other databases only through permissions granted in those databases to guest. Therefore, any database in which guest has been disabled will be inaccessible to application roles in other databases.
Can someone explain this to me?
Does this mean that I cannot write a cross database query which refers to tables from another database on the same SQL Server Instance if guest account is disabled for that instance?
First, disabling the guest account on an instance is IMHO a bad idea. The guest account is designed to allow users to "see" databases (and very little more). Disabling the guest account for the instance (and consequestially master) will stop enumeration of the databases which may well stop an otherwise authenticated role connecting, depending on the connection string used. You can grant an application role to one or more databases and instances and the application running under this account will have access (unless its denied in some other way) Thus any userrs who can run the applicaion will have that access via the application) Its a way of allowing an application t do something without granting the user those rights. http://msdn.microsoft.com/en-us/library/aa905195%28v=sql.80%29.aspx By Instance I presume you mean sQL install instance...?
Related
I have made a Simple CRUD application made in VB with the data stored in SQL Server on my local machine.
Within the Database security I have made Database Roles and assigned permissions accordingly, and added my (Domain) Computer user account into the Role.
My connection string is;
Data Source=(LocalDB)\MSSQLLocalDB;Initial Catalog=Assets;Integrated Security=SSPI
Now when I run my application it assumes the dbo role instead of the user who is running the application. As this is intended to run on a central machine and have multiple users connecting to it, with different permissions, what changes do I need to make so that I connect using my domain user account?
When I run commands in SSMS with the EXECUTE AS USER command the permissions apply.
If you want users to connect via their Windows login, your connection string is fine. However, you need to recongifure your security model. Ideally, you'll want to create one Active Directory group per application role. Then, you'd add users' Windows accounts to the appropriate AD group. Now, on SQL Server, you'd add the AD groups to the appropriate database roles.
For example, you create a database role "db_read_only". You'd create an AD group "MyApp.ReadOnly", using your company's AD group naming convention of course. You'd then add MyApp.ReadOnly to your database's db_read_only DB role. Then, John Doe wants read-only access to your app, so he'd request to be added to AD group MyApp.ReadOnly.
Your app roles define how many AD groups and DB roles you'd need. You might have MyApp.Admin, MyApp.DataEntry, MyApp.Approver... whatever.
My requirement I have 20 users all are configured in azure active directory resource group.
I have one Azure SQL Server under I have 3 Azure SQL Databases like Dev, QA and UAT
In Active Directory configured 20 users I need different access in each database level, some people need only read access and some people need both write and read, etc.
Please help me to do this.
Is it possible to create users group in each database level with different roles for azure active directory users?
users can login SSMS with azure active directory credentials but each user having different access in each database
you can create groups in AAD and provide the groups/users access on the database individually.
Execute the below queries in individual databases:
1)
CREATE USER [GroupName] FROM EXTERNAL PROVIDER or
CREATE USER [xyz#abc.com] FROM EXTERNAL PROVIDER
2)
exec sp_addrolemember 'db_datareader', '<>' or
exec sp_addrolemember 'dbowner', '<>' etc based on the roles which you want to assign.
Note :
Since the user is not created at server level and directly at databases level, while trying to connect via SSMS ,
Put the database name explicitly.
Per my experience, you need manually configure the AAD users with different permissions or database role in each database.
In addition, you need connect to the Azure SQL with Azure AD admin account, only the admin account can do the operations for each database.
For example, one of the AAD user 'aa#abc.com' only needs have the read permission in database Dev but needs read/writer permission in database QA and UAT. User 'bb#abc.com' needs read/writer permission in database 'Dev' and read permission in 'QA' and 'UAT'. In each database, different users are derived to two roles. Then we can not configure group level permission for these AAD users in each database.
After doing that, all the users in your AAD group will have the different permissions in different database. When connect to the database with SSMS, current user can see all the databases which he has the permission to access. You also can choose the specific database in SSMS connection properties like #Nandan said.
HTH.
I have been searching for articles and SQL script examples that would demonstrate how to securely and conveniently solve one of the most common scenarios - connecting from a .Net Core Entity Framework based web application to an SQL database.
But somehow I could not find any coherent step-by-step guide from a reputable source.
Let's assume the following:
I cannot use integrated Windows auth in the connection string and must use username and password based auth (because hosting on a Linux server and the DB is on a different Windows server)
the web service will need your usual minimum set of permissions - connect to the database, read data, write data, delete data, execute stored procedures
While reading many tutorials, I find there are multiple ways to manage the connection permissions. To avoid this question being too broad, I'll list my current choices as I understand them (please correct me if I'm missing something).
Users and logins:
create a login and a user for the database
create a database-only user without a login (not sure if this is applicable to a web app and connection string, but still it's a feature that I've seen being used)
Assigning permissions:
assign the user to some fixed SQL role (db_datareader, db_datawriter AND also will have to grant EXECUTE permission)
grant all fixed permissions
create a custom role (let's say, db_web_apps) with required permissions
Which choices are better (more secure and easier to manage in general) and recommended by SQL DBAs?
I think every database administrator should have a template script handy for quickly adding a new user with minimum required permissions every time when developers ask for a new connection for their shiny new web app.
If you know a good, reliable tutorial or GitHub / Gist example that explains what and why is being done that way or a script that you yourself have used for years without any issues in production environments, I'll really appreciate if you could share it.
Create a role in the database and assign the required privileges to the role. Don't use the fixed database roles. Instead grant permissions directly to objects, schemas, or the entire database if necessary. Like this:
create role trusted_app_role
grant select, insert, update, delete, execute
on schema::dbo to trusted_app_role
That will grant the role full DML permissions on all the objects in the default dbo schema. So if you have any tables or procedures you don't want the app to have access to, just create them in a different schema, say, admin. This way you never have to fiddle with permissions as you add objects. The fixed database roles predate schema-based permissions, and aren't really needed any more.
For your application's identity, add Active Directory or Azure Active Directory (Azure SQL) identities to this role, or, if you can't, add SQL Users to the role.
If you are on Azure SQL, you should normally use a database user without a login. On SQL Server you can only add "contained database users" if you enable Partial Database Containment. Which you can do, but is incompatible with Change Tracking and Change Data Capture, so it's a tradeoff.
So normally for SQL Server you still create a login and map the user to the login. EG:
create login web_service_user with password = '5X+jeuAB6kmhw85R/AxAg'
create user web_service_user for login web_service_user
And then add that user to your role
alter role trusted_app_role add member web_service_user
I see Navision uses SQL application roles to manage user permissions to select, insert, delete data in its tables.
I see that for each navision user, exists a SQL database user with the same name.
Relation between nav roles and sql aplication roles is not direct. It seems there are as many SQL application roles as diferent sets of nav roles are applied to all nav users.
Anyway I guess there is some place where it is stored which SQL application roles each user must use. Do you know where it is stored this info? The SQL application roles names are a litlle criptic... Do they have some meaning?
Well "enhanced" is strange mechanism. As it mentioned here it has a "activation mechanism" for application roles and almost no documentation (even on administrating level).
As far as I understand this is the way it meant to be used: you enable enhanced level and administrating users and their roles in Nav, after that you develop (or use) third-party application that uses Nav data through SQL Server directly (loosing all business logic of course). In this case you can use same user credentials both in Nav and in the application and have same access level to the data (and same restrictions). But this does not mean you can manage permissions outside of Navision. Moreover because of mentioned "activation mechanism" the only place to manage security is classic client.
In case of standard security application user will have SQL-managed set of permissions and Nav user will be restricted by Nav Roles. And be the happiness.
If you are using Database Logins, then the logins are validated against those stored in the database. Windows logins are managed by the domain and a validated in the Active Directory during login. In both cases individual table insert/update/rename/delete permissions are set in NAV under a NAV 'role' (Tools > Security > Roles).
Classic Client
If a user needs access to the classic client, a group or user could be used in SQL to give the dataread, datawrite SQL roles.
Role-tailored Client
NAV 2009 R2 is in the three-tier architecture, so if you're using RTC, you should make sure your service tier account has access to the SQL database, but apart from that permissions for individual users are managed from the Classic Client (Tools > Security).
I believe Windows auth is the best practice to use to connect to SQL DB. I am hear talking about application user account..
Is it true that SQL auth is only great for multiple role apps and window auth is only good for single role app? I never heard that windows auth with muitple role os only good for smaill internal app?
multiple Windows logins = multiple connections = no pooling = poor scaling?
The problem with using Windows auth for a web application is that many web applications store their application users' credentials in the same SQL database that is used for other application data.
So you have a chicken-and-egg problem. You can't authenticate the user before connecting to the database, and you can't connect to the database without authenticating the user.
It should be possible to use Windows authentication, and then also have application-specific attributes of the user stored inside the database. But most people find this cumbersome to administer, and also limiting to portability of the application.
For example, if one of the feature of the application allows users to change their own password, then the process running your web application needs the privilege to alter a Windows password, which may mean that the application needs to run with Administrator privileges.
If you let the application manage user ID for the context of the application, then to change a user's password is just an SQL operation, and your application is in charge of enforcing security for that.
I'm not sure what you mean by single-role and multi-role app. I have built apps before where there are multiple SQL Server Database Roles, each with a Windows Domain Group of users allowed in that role. So user management is completely within Active Directory, with a 1-1 correspondence between the Domain Group and the Database Role.
We typically did not manage the security within the application itself except obviously declaratively during the database creation where each object was granted access by particular roles according to the design. Typically, in a simple case, we relied on db_datareader role being granted for general usage to non-specific groups of users like database and network administrators for troubleshooting or report-writers or business analysts for ad hoc reporting. Actual users of the app would be granted execute on the relevant SPs to be able to modify any data (so all data creation or modification was through SPs and only explicit members of the ThisAppsUsers AD group could do it). Any advanced SPs (say, merging or deleting accounts) would only be accessible by ThisAppsAdmins AD group. And that was usually all we needed for moderate-sized applications. For more complex functionality, it was also possible to interrogate AD directly for custom attributes (user is an admin only for this customer account but for others is just a user)
This same technique can be used with SQL Server logins, but of course the individual SQL Server logins have to be added to the database roles, and you don't have the richness of AD and have to build some kind of directory service into your database.
The ability to even use AD may not be possible for many applications, so in that case, the security architecture would obviously have to cater to that model.
using the integratedSecurity=true option for SQL JDBC , by including the JDBC auth .dll, should give you database connectivity without authenticating...