Merge pull request 'feat(auth): Microsoft OAuth sign-in/link + self-serve signup via Google/Microsoft' (#22) from feature/wave7-oauth-signup into main

JobTrackerApi/Services/MicrosoftTokenValidator.cs

@@ -0,0 +1,100 @@
+using System.IdentityModel.Tokens.Jwt;
+using System.Security.Claims;
+using Microsoft.IdentityModel.Protocols;
+using Microsoft.IdentityModel.Protocols.OpenIdConnect;
+using Microsoft.IdentityModel.Tokens;
+
+namespace JobTrackerApi.Services;
+
+public sealed record MicrosoftTokenPrincipal(string Subject, string? Email, bool EmailVerified, string? GivenName, string? FamilyName, string? Name);
+
+public interface IMicrosoftTokenValidator
+{
+    Task<MicrosoftTokenPrincipal> ValidateAsync(string idToken, CancellationToken cancellationToken = default);
+}
+
+public sealed class MicrosoftTokenValidator : IMicrosoftTokenValidator
+{
+    private readonly IConfiguration _cfg;
+    private readonly IConfigurationManager<OpenIdConnectConfiguration> _configManager;
+
+    public MicrosoftTokenValidator(IConfiguration cfg)
+    {
+        _cfg = cfg;
+        // "common" endpoint: accepts both personal Microsoft accounts and work/school (Entra ID) tenants.
+        _configManager = new ConfigurationManager<OpenIdConnectConfiguration>(
+            "https://login.microsoftonline.com/common/v2.0/.well-known/openid-configuration",
+            new OpenIdConnectConfigurationRetriever());
+    }
+
+    public MicrosoftTokenValidator(IConfiguration cfg, IConfigurationManager<OpenIdConnectConfiguration> configManager)
+    {
+        _cfg = cfg;
+        _configManager = configManager;
+    }
+
+    public async Task<MicrosoftTokenPrincipal> ValidateAsync(string idToken, CancellationToken cancellationToken = default)
+    {
+        var audience = (_cfg["Auth:MicrosoftClientId"] ?? "").Trim();
+        if (string.IsNullOrWhiteSpace(audience))
+        {
+            throw new InvalidOperationException("Microsoft sign-in is not configured.");
+        }
+
+        var config = await _configManager.GetConfigurationAsync(cancellationToken);
+        var handler = new JwtSecurityTokenHandler
+        {
+            // The handler's default inbound claim map rewrites "oid"/"tid" to long Microsoft
+            // schema URIs (an AAD-specific quirk not shared by Google's OIDC claims) -- keep
+            // claim names as issued so FindFirst("oid") below actually matches.
+            MapInboundClaims = false,
+        };
+        // ponytail: multi-tenant "common" app -- each tenant's issuer embeds its own tenant id
+        // (https://login.microsoftonline.com/{tenantId}/v2.0), so issuer is checked by shape below
+        // rather than pinned to one value. Signature/audience/lifetime are still fully validated.
+        var principal = handler.ValidateToken(idToken, new TokenValidationParameters
+        {
+            ValidateIssuer = false,
+            ValidateAudience = true,
+            ValidAudience = audience,
+            ValidateLifetime = true,
+            ValidateIssuerSigningKey = true,
+            IssuerSigningKeys = config.SigningKeys,
+            ClockSkew = TimeSpan.FromMinutes(2),
+        }, out var validatedToken);
+
+        var issuer = (validatedToken as JwtSecurityToken)?.Issuer ?? principal.FindFirst("iss")?.Value ?? "";
+        if (!IsMicrosoftIssuer(issuer))
+        {
+            throw new InvalidOperationException("Microsoft token has an unexpected issuer.");
+        }
+
+        var subject = principal.FindFirst("oid")?.Value?.Trim()
+            ?? principal.FindFirst(JwtRegisteredClaimNames.Sub)?.Value?.Trim()
+            ?? principal.FindFirst(ClaimTypes.NameIdentifier)?.Value?.Trim();
+        if (string.IsNullOrWhiteSpace(subject))
+        {
+            throw new InvalidOperationException("Microsoft token is missing a subject.");
+        }
+
+        var email = principal.FindFirst("email")?.Value?.Trim()
+            ?? principal.FindFirst(ClaimTypes.Email)?.Value?.Trim()
+            ?? principal.FindFirst("preferred_username")?.Value?.Trim();
+
+        return new MicrosoftTokenPrincipal(
+            Subject: subject,
+            Email: email,
+            // Microsoft ID tokens don't carry an email_verified claim; presence of an email claim
+            // from a signature-validated token is treated as verified, same trust level Microsoft's
+            // own APIs give it.
+            EmailVerified: !string.IsNullOrWhiteSpace(email),
+            GivenName: principal.FindFirst("given_name")?.Value?.Trim(),
+            FamilyName: principal.FindFirst("family_name")?.Value?.Trim(),
+            Name: principal.FindFirst("name")?.Value?.Trim() ?? principal.Identity?.Name?.Trim()
+        );
+    }
+
+    private static bool IsMicrosoftIssuer(string issuer)
+        => issuer.StartsWith("https://login.microsoftonline.com/", StringComparison.OrdinalIgnoreCase)
+            && issuer.EndsWith("/v2.0", StringComparison.OrdinalIgnoreCase);
+}

JobTrackerApi/Services/StartupInitializationExtensions.cs

@@ -241,6 +241,9 @@ public static class StartupInitializationExtensions
             `GoogleSubject` longtext NULL,
             `GoogleEmail` longtext NULL,
             `GoogleLinkedAt` datetime(6) NULL,
+            `MicrosoftSubject` longtext NULL,
+            `MicrosoftEmail` longtext NULL,
+            `MicrosoftLinkedAt` datetime(6) NULL,
             PRIMARY KEY (`Id`)
         ) CHARACTER SET=utf8mb4;
 
@@ -353,7 +356,10 @@ public static class StartupInitializationExtensions
             "AvatarImageDataUrl" TEXT NULL,
             "GoogleSubject" TEXT NULL,
             "GoogleEmail" TEXT NULL,
-            "GoogleLinkedAt" TEXT NULL
+            "GoogleLinkedAt" TEXT NULL,
+            "MicrosoftSubject" TEXT NULL,
+            "MicrosoftEmail" TEXT NULL,
+            "MicrosoftLinkedAt" TEXT NULL
         );
         """);
 
@@ -431,6 +437,9 @@ public static class StartupInitializationExtensions
                 EnsureColumn(conn, "AspNetUsers", "GoogleSubject", "ALTER TABLE AspNetUsers ADD COLUMN GoogleSubject TEXT NULL;");
                 EnsureColumn(conn, "AspNetUsers", "GoogleEmail", "ALTER TABLE AspNetUsers ADD COLUMN GoogleEmail TEXT NULL;");
                 EnsureColumn(conn, "AspNetUsers", "GoogleLinkedAt", "ALTER TABLE AspNetUsers ADD COLUMN GoogleLinkedAt TEXT NULL;");
+                EnsureColumn(conn, "AspNetUsers", "MicrosoftSubject", "ALTER TABLE AspNetUsers ADD COLUMN MicrosoftSubject TEXT NULL;");
+                EnsureColumn(conn, "AspNetUsers", "MicrosoftEmail", "ALTER TABLE AspNetUsers ADD COLUMN MicrosoftEmail TEXT NULL;");
+                EnsureColumn(conn, "AspNetUsers", "MicrosoftLinkedAt", "ALTER TABLE AspNetUsers ADD COLUMN MicrosoftLinkedAt TEXT NULL;");
 
                 static void EnsureUserRuleSettingsTable(DbConnection c)
                 {
@@ -757,6 +766,9 @@ public static class StartupInitializationExtensions
                     EnsureMySqlColumn(conn, "AspNetUsers", "GoogleSubject", "ALTER TABLE `AspNetUsers` ADD COLUMN `GoogleSubject` longtext NULL;");
                     EnsureMySqlColumn(conn, "AspNetUsers", "GoogleEmail", "ALTER TABLE `AspNetUsers` ADD COLUMN `GoogleEmail` longtext NULL;");
                     EnsureMySqlColumn(conn, "AspNetUsers", "GoogleLinkedAt", "ALTER TABLE `AspNetUsers` ADD COLUMN `GoogleLinkedAt` datetime NULL;");
+                    EnsureMySqlColumn(conn, "AspNetUsers", "MicrosoftSubject", "ALTER TABLE `AspNetUsers` ADD COLUMN `MicrosoftSubject` longtext NULL;");
+                    EnsureMySqlColumn(conn, "AspNetUsers", "MicrosoftEmail", "ALTER TABLE `AspNetUsers` ADD COLUMN `MicrosoftEmail` longtext NULL;");
+                    EnsureMySqlColumn(conn, "AspNetUsers", "MicrosoftLinkedAt", "ALTER TABLE `AspNetUsers` ADD COLUMN `MicrosoftLinkedAt` datetime NULL;");
 
                     if (!HasMySqlTable(conn, "RuleSettings"))
                     {