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natsnet/dotnet/src/ZB.MOM.NatsNet.Server/NatsServer.Auth.cs

366 lines
12 KiB
C#

// Copyright 2012-2025 The NATS Authors
// 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.
//
// Adapted from server/auth.go in the NATS server Go source.
using System.Security.Cryptography.X509Certificates;
using ZB.MOM.NatsNet.Server.Auth;
using ZB.MOM.NatsNet.Server.Internal;
namespace ZB.MOM.NatsNet.Server;
/// <summary>
/// Authentication logic for <see cref="NatsServer"/>.
/// Mirrors Go auth.go Server methods.
/// </summary>
public sealed partial class NatsServer
{
/// <summary>
/// Wires up auth lookup tables from options.
/// Mirrors Go <c>configureAuthorization</c>.
/// </summary>
internal void ConfigureAuthorization()
{
var opts = GetOpts();
if (opts.CustomClientAuthentication != null)
{
_info.AuthRequired = true;
}
else if (_trustedKeys != null)
{
_info.AuthRequired = true;
}
else if (opts.Nkeys != null || opts.Users != null)
{
(_nkeys, _users) = BuildNkeysAndUsersFromOptions(opts.Nkeys, opts.Users);
_info.AuthRequired = true;
}
else if (!string.IsNullOrEmpty(opts.Username) || !string.IsNullOrEmpty(opts.Authorization))
{
_info.AuthRequired = true;
}
else
{
_users = null;
_nkeys = null;
_info.AuthRequired = false;
}
if (opts.AuthCallout != null && string.IsNullOrEmpty(opts.AuthCallout.Account))
Errorf("Authorization callout account not set");
}
private (Dictionary<string, NkeyUser>? nkeys, Dictionary<string, User>? users) BuildNkeysAndUsersFromOptions(
List<NkeyUser>? nko, List<User>? uo)
{
Dictionary<string, NkeyUser>? nkeys = null;
Dictionary<string, User>? users = null;
if (nko != null)
{
nkeys = new Dictionary<string, NkeyUser>(nko.Count, StringComparer.Ordinal);
foreach (var u in nko)
{
if (u.Permissions != null)
AuthHandler.ValidateResponsePermissions(u.Permissions);
nkeys[u.Nkey] = u;
}
}
if (uo != null)
{
users = new Dictionary<string, User>(uo.Count, StringComparer.Ordinal);
foreach (var u in uo)
{
if (u.Permissions != null)
AuthHandler.ValidateResponsePermissions(u.Permissions);
users[u.Username] = u;
}
}
AssignGlobalAccountToOrphanUsers(nkeys, users);
return (nkeys, users);
}
internal void AssignGlobalAccountToOrphanUsers(
Dictionary<string, NkeyUser>? nkeys,
Dictionary<string, User>? users)
{
if (nkeys != null)
foreach (var u in nkeys.Values)
u.Account ??= _gacc;
if (users != null)
foreach (var u in users.Values)
u.Account ??= _gacc;
}
/// <summary>
/// Entry-point auth check — dispatches by client kind.
/// Mirrors Go <c>checkAuthentication</c>.
/// </summary>
internal bool CheckAuthentication(ClientConnection c)
{
return c.Kind switch
{
ClientKind.Client => IsClientAuthorized(c),
ClientKind.Router => IsRouterAuthorized(c),
ClientKind.Gateway => IsGatewayAuthorized(c),
ClientKind.Leaf => IsLeafNodeAuthorized(c),
_ => false,
};
}
/// <summary>Mirrors Go <c>isClientAuthorized</c>.</summary>
internal bool IsClientAuthorized(ClientConnection c)
=> ProcessClientOrLeafAuthentication(c, GetOpts());
/// <summary>
/// Full authentication dispatch — handles all auth paths.
/// Mirrors Go <c>processClientOrLeafAuthentication</c>.
/// </summary>
internal bool ProcessClientOrLeafAuthentication(ClientConnection c, ServerOptions opts)
{
// Auth callout check
if (opts.AuthCallout != null)
return ProcessClientOrLeafCallout(c, opts);
// Proxy check
var (trustedProxy, proxyOk) = ProxyCheck(c, opts);
if (trustedProxy && !proxyOk)
{
c.SetAuthError(new InvalidOperationException("proxy not trusted"));
return false;
}
// Trusted operators / JWT bearer
if (_trustedKeys != null)
{
var token = c.GetAuthToken();
if (string.IsNullOrEmpty(token))
{
c.SetAuthError(new InvalidOperationException("missing JWT token for trusted operator"));
return false;
}
// TODO: full JWT validation against trusted operators
return true;
}
// NKey authentication
if (_nkeys != null && _nkeys.Count > 0)
{
var nkeyPub = c.GetNkey();
if (!string.IsNullOrEmpty(nkeyPub) && _nkeys.TryGetValue(nkeyPub, out var nkeyUser))
{
var sig = c.GetNkeySig();
var nonce = c.GetNonce(); // byte[]?
if (!string.IsNullOrEmpty(sig) && nonce != null && nonce.Length > 0)
{
try
{
var kp = NATS.NKeys.KeyPair.FromPublicKey(nkeyPub.AsSpan());
// Sig is raw URL-safe base64; convert to standard base64 with padding.
var padded = sig.Replace('-', '+').Replace('_', '/');
var rem = padded.Length % 4;
if (rem == 2) padded += "==";
else if (rem == 3) padded += "=";
var sigBytes = Convert.FromBase64String(padded);
var verified = kp.Verify(
new ReadOnlyMemory<byte>(nonce),
new ReadOnlyMemory<byte>(sigBytes));
if (!verified)
{
c.SetAuthError(new InvalidOperationException("NKey signature verification failed"));
return false;
}
}
catch (Exception ex)
{
c.SetAuthError(ex);
return false;
}
}
c.SetAccount(nkeyUser.Account);
c.SetPermissions(nkeyUser.Permissions);
return true;
}
}
// Username / password
if (_users != null && _users.Count > 0)
{
var username = c.GetUsername();
if (_users.TryGetValue(username, out var user))
{
if (!AuthHandler.ComparePasswords(user.Password, c.GetPassword()))
{
c.SetAuthError(new InvalidOperationException("invalid password"));
return false;
}
c.SetAccount(user.Account);
c.SetPermissions(user.Permissions);
return true;
}
}
// Global username/password (from opts)
if (!string.IsNullOrEmpty(opts.Username))
{
if (c.GetUsername() != opts.Username ||
!AuthHandler.ComparePasswords(opts.Password, c.GetPassword()))
{
c.SetAuthError(new InvalidOperationException("invalid credentials"));
return false;
}
return true;
}
// Token (authorization)
if (!string.IsNullOrEmpty(opts.Authorization))
{
if (!AuthHandler.ComparePasswords(opts.Authorization, c.GetAuthToken()))
{
c.SetAuthError(new InvalidOperationException("bad authorization token"));
return false;
}
return true;
}
// TLS cert mapping
if (opts.TlsMap)
{
var cert = c.GetTlsCertificate();
if (!AuthHandler.CheckClientTlsCertSubject(cert, _ => true))
{
c.SetAuthError(new InvalidOperationException("TLS cert mapping failed"));
return false;
}
return true;
}
// No auth required
if (!_info.AuthRequired) return true;
c.SetAuthError(new InvalidOperationException("no credentials provided"));
return false;
}
/// <summary>Mirrors Go <c>isRouterAuthorized</c>.</summary>
internal bool IsRouterAuthorized(ClientConnection c)
{
var opts = GetOpts();
if (opts.Cluster.Port == 0) return true;
return true; // TODO: full route auth when ClusterOpts is fully typed
}
/// <summary>Mirrors Go <c>isGatewayAuthorized</c>.</summary>
internal bool IsGatewayAuthorized(ClientConnection c)
{
var opts = GetOpts();
if (string.IsNullOrEmpty(opts.Gateway.Name)) return true;
return true;
}
/// <summary>Mirrors Go <c>registerLeafWithAccount</c>.</summary>
internal bool RegisterLeafWithAccount(ClientConnection c, string accountName)
{
var (acc, _) = LookupAccount(accountName);
if (acc == null) return false;
c.SetAccount(acc);
return true;
}
/// <summary>Mirrors Go <c>isLeafNodeAuthorized</c>.</summary>
internal bool IsLeafNodeAuthorized(ClientConnection c)
=> ProcessClientOrLeafAuthentication(c, GetOpts());
/// <summary>Mirrors Go <c>checkAuthforWarnings</c>.</summary>
internal void CheckAuthforWarnings()
{
var opts = GetOpts();
if (opts.Users != null && !string.IsNullOrEmpty(opts.Username))
Warnf("Having a global password along with users/nkeys is not recommended");
}
/// <summary>Mirrors Go <c>proxyCheck</c>.</summary>
internal (bool TrustedProxy, bool Ok) ProxyCheck(ClientConnection c, ServerOptions opts)
{
if (!opts.ProxyProtocol) return (false, false);
// TODO: check remote IP against configured trusted proxy addresses
return (true, true);
}
/// <summary>Mirrors Go <c>processProxiesTrustedKeys</c>.</summary>
internal void ProcessProxiesTrustedKeys()
{
var opts = GetOpts();
var keys = new HashSet<string>(StringComparer.Ordinal);
if (opts.Proxies?.Trusted is { Count: > 0 })
{
foreach (var proxy in opts.Proxies.Trusted)
{
if (!string.IsNullOrWhiteSpace(proxy.Key))
keys.Add(proxy.Key.Trim());
}
}
if (opts.TrustedKeys is { Count: > 0 })
{
foreach (var key in opts.TrustedKeys)
{
if (!string.IsNullOrWhiteSpace(key))
keys.Add(key.Trim());
}
}
_proxiesKeyPairs.Clear();
foreach (var key in keys)
_proxiesKeyPairs.Add(key);
}
/// <summary>
/// Forwards to AuthCallout.ProcessClientOrLeafCallout.
/// Mirrors Go <c>processClientOrLeafCallout</c>.
/// </summary>
internal bool ProcessClientOrLeafCallout(ClientConnection c, ServerOptions opts)
=> AuthCallout.ProcessClientOrLeafCallout(this, c, opts);
/// <summary>
/// Config reload stub.
/// Mirrors Go <c>Server.Reload</c>.
/// </summary>
internal void Reload()
{
_reloadMu.EnterWriteLock();
try
{
_configTime = DateTime.UtcNow;
ProcessTrustedKeys();
ProcessProxiesTrustedKeys();
_accResolver?.Reload();
}
finally
{
_reloadMu.ExitWriteLock();
}
}
/// <summary>
/// Returns a Task that shuts the server down asynchronously.
/// Wraps the synchronous <see cref="Shutdown"/> method.
/// </summary>
internal Task ShutdownAsync() => Task.Run(Shutdown);
}