[SM-220] Move identity specific files to identity (#2279)

src/Admin/IdentityServer/ReadOnlyEnvIdentityUserStore.cs

@@ -0,0 +1,65 @@
+using Bit.Core.Utilities;
+using Microsoft.AspNetCore.Identity;
+
+namespace Bit.Admin.IdentityServer;
+
+public class ReadOnlyEnvIdentityUserStore : ReadOnlyIdentityUserStore
+{
+    private readonly IConfiguration _configuration;
+
+    public ReadOnlyEnvIdentityUserStore(IConfiguration configuration)
+    {
+        _configuration = configuration;
+    }
+
+    public override Task<IdentityUser> FindByEmailAsync(string normalizedEmail,
+        CancellationToken cancellationToken = default)
+    {
+        var usersCsv = _configuration["adminSettings:admins"];
+        if (!CoreHelpers.SettingHasValue(usersCsv))
+        {
+            return Task.FromResult<IdentityUser>(null);
+        }
+
+        var users = usersCsv.ToLowerInvariant().Split(',');
+        var usersDict = new Dictionary<string, string>();
+        foreach (var u in users)
+        {
+            var parts = u.Split(':');
+            if (parts.Length == 2)
+            {
+                var email = parts[0].Trim();
+                var stamp = parts[1].Trim();
+                usersDict.Add(email, stamp);
+            }
+            else
+            {
+                var email = parts[0].Trim();
+                usersDict.Add(email, email);
+            }
+        }
+
+        var userStamp = usersDict.ContainsKey(normalizedEmail) ? usersDict[normalizedEmail] : null;
+        if (userStamp == null)
+        {
+            return Task.FromResult<IdentityUser>(null);
+        }
+
+        return Task.FromResult(new IdentityUser
+        {
+            Id = normalizedEmail,
+            Email = normalizedEmail,
+            NormalizedEmail = normalizedEmail,
+            EmailConfirmed = true,
+            UserName = normalizedEmail,
+            NormalizedUserName = normalizedEmail,
+            SecurityStamp = userStamp
+        });
+    }
+
+    public override Task<IdentityUser> FindByIdAsync(string userId,
+        CancellationToken cancellationToken = default)
+    {
+        return FindByEmailAsync(userId, cancellationToken);
+    }
+}