prisma/tiberius

Tiberius

A native Microsoft SQL Server (TDS) client for Rust.

Goals

• A perfect implementation of the TDS protocol.
• Asynchronous network IO.
• Independent of the network protocol.
• Support for latest versions of Linux, Windows and macOS.

Non-goals

• Connection pooling (use bb8, mobc, deadpool or any of the other asynchronous connection pools)
• Query building
• Object-relational mapping

Supported SQL Server versions

Feature flags

Supported protocols

Tiberius does not rely on any protocol when connecting to an SQL Server instance. Instead the Client takes a socket that implements the AsyncRead and AsyncWrite traits from the futures-rs crate.

Currently there are good async implementations for TCP in the async-std, Tokio and Smol projects.

To be able to use them together with Tiberius on Windows platforms with SQL Server, you should make sure that the TCP protocol is enabled, as depending on the edition, this may not be the case. Standard and Enterprise editions will have the setting enabled by default, whereas Developer, Express editions and the Windows Internal Database feature of the Windows Server OS don't. To enable the TCP/IP protocol you may want to use the server settings the command line. In the official Docker image TCP is is enabled by default.

Named pipes should work by using the NamedPipeClient from the latest Tokio versions.

The shared memory protocol is not documented and seems there are no Rust crates implementing it.

Encryption (TLS/SSL)

Tiberius can be set to use two different implementations of TLS connection encryption. By default it uses native-tls, linking to the TLS library provided by the operating system. This is a good practice and in case of security vulnerabilities, upgrading the system libraries fixes the vulnerability in Tiberius without a recompilation. On Linux we link against OpenSSL, on Windows against schannel and on macOS against Security Framework.

Alternatively one can use the rustls feature flag to use the Rust native TLS implementation. This way there are no dynamic dependencies to the system. This might be useful in certain installations, but requires a rebuild to update to a new TLS version. For some reasons the Security Framework on macOS does not work with SQL Server TLS settings, and on Apple platforms if needing TLS it is recommended to use rustls instead of native-tls. The other option is to use the vendored-openssl feature flag, that statically links against the latest OpenSSL implementation.

The crate can also be compiled without TLS support, but not with both features enabled at the same time.

Tiberius has three runtime encryption settings:

The encryption levels can be set when connecting to the database.

Integrated Authentication (TrustedConnection) on *nix

With the integrated-auth-gssapi feature enabled, the crate requires the GSSAPI/Kerberos libraries/headers installed:

• CentOS
• Arch
• Debian (you need the -dev packages to build)
• Ubuntu
• NixOS: Run nix-shell shell.nix on the repository root.
• Mac: as of version 0.4.2 the libgssapi crate used for this feature now uses Apple's GSS Framework which ships with MacOS 10.14+.

Additionally, your runtime system will need to be trusted by and configured for the Active Directory domain your SQL Server is part of. In particular, you'll need to be able to get a valid TGT for your identity, via kinit or a keytab. This setup varies by environment and OS, but your friendly network/system administrator should be able to help figure out the specifics.

Redirects

With certain Azure firewall settings, a login might return Error::Routing { host, port }. This means the user must create a new TcpStream to the given address, and connect again.

A simple connection procedure would then be:

use tiberius::{Client, Config, AuthMethod, error::Error};
use tokio_util::compat::TokioAsyncWriteCompatExt;
use tokio::net::TcpStream;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let mut config = Config::new();

    config.host("0.0.0.0");
    config.port(1433);
    config.authentication(AuthMethod::sql_server("SA", "<Mys3cureP4ssW0rD>"));

    let tcp = TcpStream::connect(config.get_addr()).await?;
    tcp.set_nodelay(true)?;

    let client = match Client::connect(config, tcp.compat_write()).await {
        // Connection successful.
        Ok(client) => client,
        // The server wants us to redirect to a different address
        Err(Error::Routing { host, port }) => {
            let mut config = Config::new();

            config.host(&host);
            config.port(port);
            config.authentication(AuthMethod::sql_server("SA", "<Mys3cureP4ssW0rD>"));

            let tcp = TcpStream::connect(config.get_addr()).await?;
            tcp.set_nodelay(true)?;

            // we should not have more than one redirect, so we'll short-circuit here.
            Client::connect(config, tcp.compat_write()).await?
        }
        Err(e) => Err(e)?,
    };

    Ok(())
}

Security

If you have a security issue to report, please contact us at [email protected]