diff --git a/nodejs/app.js b/nodejs/app.js
index b64b5d4..a829835 100755
--- a/nodejs/app.js
+++ b/nodejs/app.js
@@ -7,6 +7,11 @@ const express = require('express');
 // Set up the express app.
 const app = express();
 
+// The app always runs behind the OpenResty reverse proxy (a single hop) which
+// sets X-Real-IP / X-Forwarded-For. Trust that one proxy so req.ip reflects the
+// real client — needed for correct per-client rate limiting on /api/auth.
+app.set('trust proxy', 1);
+
 // Hold list of functions to run when the server is ready
 app.onListen = [];
 
diff --git a/nodejs/conf/base.js b/nodejs/conf/base.js
index d670d31..a10c2fe 100644
--- a/nodejs/conf/base.js
+++ b/nodejs/conf/base.js
@@ -22,6 +22,40 @@ module.exports = {
 	// self-correct. 0 disables expiry (entries live until bustCache/clearCache).
 	cacheTTL: 3600,
 
+	// OpenID Connect login against the SSO. Endpoints come from the SSO's
+	// /.well-known/openid-configuration. clientSecret lives in secrets.js.
+	// redirectUri MUST be registered on the SSO client and match exactly.
+	oidc: {
+		enabled: true,
+		issuer: 'https://sso.theta42.com',
+		authorizationEndpoint: 'https://sso.theta42.com/oauth/authorize',
+		tokenEndpoint: 'https://sso.theta42.com/oauth/token',
+		userinfoEndpoint: 'https://sso.theta42.com/oauth/userinfo',
+		endSessionEndpoint: 'https://sso.theta42.com/oauth/logout',
+		clientId: '__SET_ME__',
+		// Where the SSO sends the user back. Must be an absolute URL reachable
+		// by the browser and registered on the SSO client.
+		redirectUri: 'http://localhost:3000/api/auth/oidc/callback',
+		scopes: ['openid', 'profile', 'email', 'groups'],
+		// Claim on the userinfo response that carries group membership.
+		groupsClaim: 'groups',
+		// Claim used as the local username.
+		usernameClaim: 'preferred_username',
+	},
+
+	// Authorization: how groups map to roles, and which groups are global admin.
+	// Per-user overrides are Grant records managed in the app.
+	auth: {
+		// Members of these SSO/LDAP groups are always global admins.
+		adminGroups: [],
+		// Optional default role mapping for groups, e.g.
+		//   { 'dns-team': { role: 'manager', scope: 'domain', domain: 'foo.com' } }
+		//   { 'proxy-viewers': { role: 'viewer', scope: 'global' } }
+		groupRoleMap: {},
+		// Local users always treated as global admin (anti-lockout bootstrap).
+		adminUsers: ['proxyadmin2'],
+	},
+
 	service:{
 		hostScheduler:{
 			enabled: true,
diff --git a/nodejs/middleware/auth.js b/nodejs/middleware/auth.js
index 7918d9a..3de1a8b 100755
--- a/nodejs/middleware/auth.js
+++ b/nodejs/middleware/auth.js
@@ -6,6 +6,8 @@ async function auth(req, res, next){
 	try{
 		req.token = await Auth.checkToken(req.header('auth-token'));
 		req.user = req.token.user;
+		// Session group memberships captured at login, used by authz middleware.
+		req.groups = typeof req.token.groupsArray === 'function' ? req.token.groupsArray() : [];
 		return next();
 	}catch(error){
 		next(error);
diff --git a/nodejs/middleware/authz.js b/nodejs/middleware/authz.js
new file mode 100644
index 0000000..b1d7c1f
--- /dev/null
+++ b/nodejs/middleware/authz.js
@@ -0,0 +1,118 @@
+'use strict';
+
+const {Grant} = require('../models/grant');
+const tldExtract = require('tld-extract').parse_host;
+
+/**
+ * Authorization middleware.
+ *
+ * Builds on middleware/auth.js (which sets req.user + req.groups). Effective
+ * rights are resolved once per request via Grant.effectiveFor and cached on
+ * req._effective. Roles: admin > manager (owner/full over a domain) > viewer.
+ */
+
+// The username for the request, tolerating a missing user relation by falling
+// back to the token's created_by (which is the username).
+function reqUsername(req){
+	return (req.user && req.user.username) || (req.token && req.token.created_by) || null;
+}
+
+// Normalize a host or domain string to its registrable domain.
+function toDomain(value){
+	if(!value) return value;
+	try{
+		return tldExtract(value).domain;
+	}catch(error){
+		return value;
+	}
+}
+
+// Resolve (and cache) the effective rights for this request.
+async function getEffective(req){
+	if(req._effective) return req._effective;
+	req._effective = await Grant.effectiveFor({
+		username: reqUsername(req),
+		groups: req.groups || [],
+	});
+	return req._effective;
+}
+
+function forbidden(message){
+	let error = new Error('Forbidden');
+	error.name = 'Forbidden';
+	error.message = message || 'You do not have permission to perform this action.';
+	error.status = 403;
+	return error;
+}
+
+// Global-admin-only gate (user management, DNS providers, grant management).
+async function requireAdmin(req, res, next){
+	try{
+		let effective = await getEffective(req);
+		if(effective.isAdmin) return next();
+		return next(forbidden('Administrator access required.'));
+	}catch(error){
+		return next(error);
+	}
+}
+
+/**
+ * Require at least `minRole` on the domain resolved from the request.
+ *
+ * @param {string} minRole - 'viewer' | 'manager'
+ * @param {Function} resolveDomain - (req) => host|domain string
+ */
+function requireDomainRole(minRole, resolveDomain){
+	return async function(req, res, next){
+		try{
+			let effective = await getEffective(req);
+			let domain = toDomain(resolveDomain(req));
+			if(!domain) return next(forbidden('Could not determine the target domain.'));
+
+			if(Grant.allows(effective, minRole, domain)) return next();
+			return next(forbidden(`You need '${minRole}' rights on ${domain}.`));
+		}catch(error){
+			return next(error);
+		}
+	};
+}
+
+// Common domain resolvers for route wiring.
+const resolve = {
+	// A host lives in req.params.item (e.g. api.example.com -> example.com).
+	hostParam: req => req.params.item,
+	// A host being created lives in the request body.
+	hostBody: req => req.body && req.body.host,
+	// A domain (or provider domain) name in req.params.item.
+	domainParam: req => req.params.item,
+};
+
+/**
+ * Filter a list of records to those the request may at least view.
+ * Admins and holders of a global role see everything; otherwise a record is
+ * kept when its domain (via `getDomain`) is one the user has rights on.
+ *
+ * @param {Object} req
+ * @param {Array} records
+ * @param {Function} getDomain - (record) => host|domain string
+ */
+async function filterViewable(req, records, getDomain){
+	let effective = await getEffective(req);
+	if(effective.isAdmin || Grant.rank(effective.global) >= Grant.rank('viewer')){
+		return records;
+	}
+	return records.filter(function(record){
+		let domain = toDomain(getDomain(record));
+		return Grant.allows(effective, 'viewer', domain);
+	});
+}
+
+module.exports = {
+	getEffective,
+	requireAdmin,
+	requireDomainRole,
+	filterViewable,
+	resolve,
+	toDomain,
+	reqUsername,
+};
diff --git a/nodejs/migrations/grant_bootstrap.js b/nodejs/migrations/grant_bootstrap.js
new file mode 100644
index 0000000..77487fa
--- /dev/null
+++ b/nodejs/migrations/grant_bootstrap.js
@@ -0,0 +1,40 @@
+'use strict';
+
+/**
+ * Bootstrap a global-admin Grant for a user so there is always someone who can
+ * manage the system after per-domain authorization is enabled.
+ *
+ * Usage:
+ *   node migrations/grant_bootstrap.js [username]
+ *
+ * Defaults to the first entry in conf.auth.adminUsers (or 'proxyadmin2').
+ * Note: members of conf.auth.adminUsers / conf.auth.adminGroups are already
+ * treated as admins without a Grant; this just makes it explicit/visible in the
+ * grant list and survives config changes.
+ */
+
+const conf = require('@simpleworkjs/conf');
+require('../models'); // register all models
+const {Grant} = require('../models/grant');
+
+(async function(){
+	try{
+		let username = process.argv[2]
+			|| (conf.auth && conf.auth.adminUsers && conf.auth.adminUsers[0])
+			|| 'proxyadmin2';
+
+		let grant = await Grant.create({
+			subjectType: 'user',
+			subject: username,
+			scope: 'global',
+			role: 'admin',
+			created_by: username,
+		});
+
+		console.log(`Granted global admin to "${username}":`, grant.id);
+	}catch(error){
+		console.error('grant_bootstrap error', error);
+	}finally{
+		process.exit(0);
+	}
+})();
diff --git a/nodejs/models/auth.js b/nodejs/models/auth.js
index b7bb581..34f33b5 100644
--- a/nodejs/models/auth.js
+++ b/nodejs/models/auth.js
@@ -47,7 +47,10 @@ class Auth{
 	static async login(data){
 		try{
 			let user = await User.login(data);
-			let token = await AuthToken.create({username: user.username});
+			// Backends may attach group membership to the user (LDAP); default
+			// to none for local/redis users.
+			let groups = Array.isArray(user.groups) ? user.groups : [];
+			let token = await AuthToken.create({username: user.username, groups});
 
 			return {user, token}
 		}catch(error){
@@ -56,6 +59,25 @@ class Auth{
 		}
 	}
 
+	/**
+	 * Establish a session for an OIDC-authenticated identity: JIT-provision the
+	 * local user (redis-backed) and mint an AuthToken carrying the SSO groups.
+	 *
+	 * @param {Object} identity - {username, groups} from utils/oidc claims
+	 * @returns {Object} {user, token}
+	 */
+	static async oidcSession(identity){
+		let user = typeof User.upsertOidc === 'function'
+			? await User.upsertOidc(identity)
+			: await User.get(identity.username);
+		let token = await AuthToken.create({
+			username: user.username,
+			groups: identity.groups || [],
+		});
+
+		return {user, token};
+	}
+
 	/**
 	 * Validate an authentication token.
 	 *
diff --git a/nodejs/models/grant.js b/nodejs/models/grant.js
new file mode 100644
index 0000000..3ef0f6a
--- /dev/null
+++ b/nodejs/models/grant.js
@@ -0,0 +1,112 @@
+'use strict';
+
+const Table = require('.');
+const conf = require('@simpleworkjs/conf');
+const roles = require('../utils/roles');
+
+/**
+ * Grant
+ *
+ * Assigns a role to a subject (a user or a group), either globally or for a
+ * single domain. Per-user overrides and group defaults both live here; group
+ * defaults can also be seeded from conf.auth.groupRoleMap.
+ *
+ *   subjectType : 'user' | 'group'
+ *   subject     : username or group name
+ *   scope       : 'global' | 'domain'
+ *   domain      : domain name when scope==='domain' (else '*')
+ *   role        : 'admin' | 'manager' | 'viewer'
+ *
+ * See Grant.effectiveFor() for how these, plus ownership (created_by) and
+ * conf.auth, collapse into a request's effective rights.
+ */
+class Grant extends Table{
+	static _key = 'id';
+	static _keyMap = {
+		'created_by': {isRequired: true, type: 'string', min: 3, max: 500},
+		'created_on': {default: function(){return (new Date).getTime()}},
+		'id': {isRequired: true, type: 'string', min: 3, max: 1100},
+		'subjectType': {isRequired: true, type: 'string'},
+		'subject': {isRequired: true, type: 'string', min: 1, max: 500},
+		'scope': {default: 'domain', isRequired: true, type: 'string'},
+		'domain': {default: '*', isRequired: false, type: 'string'},
+		'role': {isRequired: true, type: 'string'},
+	}
+
+	static roles = ['viewer', 'manager', 'admin'];
+	// Re-export the pure helpers so existing callers (middleware/authz) can use
+	// them off the model.
+	static rank = roles.rank;
+	static maxRole = roles.maxRole;
+	static roleForDomain = roles.roleForDomain;
+	static allows = roles.allows;
+	static visibleDomains = roles.visibleDomains;
+
+	// Deterministic id so the same (subject, scope, domain) grant is a single
+	// record — re-granting updates rather than duplicating.
+	static mkId({subjectType, subject, scope, domain}){
+		return `${subjectType}:${subject}:${scope || 'domain'}:${scope === 'global' ? '*' : (domain || '*')}`;
+	}
+
+	static async create(data){
+		if(!this.roles.includes(data.role)){
+			throw this.errors.ObjectValidateError([{key: 'role', message: `role must be one of ${this.roles.join(', ')}`}]);
+		}
+		if(!['user', 'group'].includes(data.subjectType)){
+			throw this.errors.ObjectValidateError([{key: 'subjectType', message: `subjectType must be 'user' or 'group'`}]);
+		}
+		if(data.scope === 'global') data.domain = '*';
+		data.id = this.mkId(data);
+		// Upsert: replace an existing identical-scoped grant instead of 409ing.
+		try{
+			let existing = await this.get(data.id);
+			if(existing) await existing.remove();
+		}catch(error){ /* not found is fine */ }
+
+		return super.create(data);
+	}
+
+	/**
+	 * Collapse conf.auth, grant records, and resource ownership into the
+	 * effective rights for a session identity.
+	 *
+	 * @param {Object} identity - {username, groups: string[]}
+	 * @returns {Object} { isAdmin, global: role|null, domains: {domain: role} }
+	 *   - isAdmin: full access to everything.
+	 *   - global: a non-admin global role (manager/viewer) applied to every
+	 *     domain the user can see.
+	 *   - domains: explicit per-domain roles (includes owned domains).
+	 */
+	static async effectiveFor(identity){
+		let username = identity && identity.username;
+
+		// Fetch the redis-backed inputs, then hand off to the pure resolver.
+		let grants = [];
+		try{
+			grants = await this.listDetail();
+		}catch(error){ grants = []; }
+
+		// Ownership: a user has manager rights over every domain they (or the
+		// DNS provider they created) own. Domain.created_by already carries the
+		// provider creator, so a single Domain scan covers both.
+		let ownedDomains = [];
+		if(username){
+			try{
+				let Domain = require('.').models.Domain;
+				ownedDomains = (await Domain.listDetail())
+					.filter(d => d.created_by === username)
+					.map(d => d.domain);
+			}catch(error){ /* domains unavailable, skip ownership */ }
+		}
+
+		return roles.resolveEffective(identity, {
+			grants,
+			ownedDomains,
+			authConf: conf.auth || {},
+		});
+	}
+}
+
+Grant.register();
+
+module.exports = {Grant};
diff --git a/nodejs/models/index.js b/nodejs/models/index.js
index 5bd173b..beef71a 100644
--- a/nodejs/models/index.js
+++ b/nodejs/models/index.js
@@ -10,3 +10,5 @@ require('./dns_provider');
 require('./host');
 require('./token');
 require('./user');
+require('./grant');
+require('./oidc_state');
diff --git a/nodejs/models/oidc_state.js b/nodejs/models/oidc_state.js
new file mode 100644
index 0000000..d46ede4
--- /dev/null
+++ b/nodejs/models/oidc_state.js
@@ -0,0 +1,31 @@
+'use strict';
+
+const Table = require('.');
+
+/**
+ * OidcState
+ *
+ * Short-lived store for an in-flight OpenID Connect authorization request.
+ * Keyed by the random `state` value; holds the PKCE `code_verifier` and the
+ * post-login redirect target until the SSO calls us back.
+ *
+ * The record auto-expires via model-redis per-key TTL (static _ttl), so an
+ * abandoned login attempt leaves nothing behind and there is no cleanup job.
+ */
+class OidcState extends Table{
+	static _key = 'state';
+
+	// Auth round-trips are quick; 5 minutes is plenty and bounds replay.
+	static _ttl = 300;
+
+	static _keyMap = {
+		'created_on': {default: function(){return (new Date).getTime()}},
+		'state': {isRequired: true, type: 'string', min: 8, max: 500},
+		'codeVerifier': {isRequired: true, type: 'string', min: 8, max: 500},
+		'redirect': {default: '/', isRequired: false, type: 'string'},
+	}
+}
+
+OidcState.register();
+
+module.exports = {OidcState};
diff --git a/nodejs/models/token.js b/nodejs/models/token.js
index d108c1a..8af591d 100644
--- a/nodejs/models/token.js
+++ b/nodejs/models/token.js
@@ -33,13 +33,31 @@ class AuthToken extends Token{
 	static _keyMap = {
 		...super._keyMap,
 		user: {model: 'User', rel: 'one', localKey: 'created_by'},
+		// Group memberships captured at login (OIDC `groups` claim or LDAP
+		// group membership), stored as a JSON string. Drives authorization for
+		// the life of the session without re-querying the IdP on every request.
+		groups: {default: '[]', isRequired: false, type: 'string'},
 	}
 
 	static async create(data){
 		data.created_by = data.username;
+		if(Array.isArray(data.groups)){
+			data.groups = JSON.stringify(data.groups);
+		}
 		return super.create(data)
 
 	}
+
+	// Parse the stored groups JSON back into an array, tolerating bad/missing
+	// data so authorization never crashes on a malformed token.
+	groupsArray(){
+		try{
+			let parsed = JSON.parse(this.groups);
+			return Array.isArray(parsed) ? parsed : [];
+		}catch(error){
+			return [];
+		}
+	}
 }
 AuthToken.register();
 
diff --git a/nodejs/models/user_ldap.js b/nodejs/models/user_ldap.js
index bb3b6e9..6c6dfa1 100644
--- a/nodejs/models/user_ldap.js
+++ b/nodejs/models/user_ldap.js
@@ -9,6 +9,19 @@ const client = new Client({
 });
 
 
+// Best-effort group extraction from a directory entry's `memberOf` values.
+// Turns `cn=dns-team,ou=groups,dc=...` into `dns-team`. Directories that don't
+// return memberOf simply yield no groups (see conf note); explicit group-search
+// can be added later if needed.
+const parse_groups = function(memberOf){
+	if(!memberOf) return [];
+	let values = Array.isArray(memberOf) ? memberOf : [memberOf];
+	return values.map(function(dn){
+		let match = /^cn=([^,]+)/i.exec(String(dn));
+		return match ? match[1] : String(dn);
+	});
+}
+
 const user_parse = function(data){
 	if(data[conf.userNameAttribute]){
 		data.username = data[conf.userNameAttribute]
@@ -20,6 +33,8 @@ const user_parse = function(data){
 		delete data.uidNumber;
 	}
 
+	data.groups = parse_groups(data.memberOf);
+
 	return data;
 }
 
diff --git a/nodejs/models/user_redis.js b/nodejs/models/user_redis.js
index c70de74..8f66c11 100644
--- a/nodejs/models/user_redis.js
+++ b/nodejs/models/user_redis.js
@@ -2,6 +2,7 @@
 
 const Table = require('.');
 const bcrypt = require('bcrypt');
+const crypto = require('crypto');
 const saltRounds = 10;
 
 class User extends Table{
@@ -40,6 +41,28 @@ class User extends Table{
 		}
 	}
 
+	/**
+	 * Just-in-time provisioning for an OIDC-authenticated user. Creates the
+	 * local user on first login so relations (tokens, created_by, grants) have
+	 * something to point at. OIDC users get a random, unusable password — they
+	 * authenticate through the SSO, never the local password form.
+	 *
+	 * @param {Object} data - {username, ...} from the OIDC userinfo claims
+	 * @returns {User} the existing or newly created user
+	 */
+	static async upsertOidc(data){
+		try{
+			return await User.get(data.username);
+		}catch(error){
+			return await User.create({
+				username: data.username,
+				password: crypto.randomBytes(24).toString('hex'),
+				created_by: data.username,
+				backing: 'oidc',
+			});
+		}
+	}
+
 	static async login(data){
 		try{
 			let user = await User.get(data);
diff --git a/nodejs/package-lock.json b/nodejs/package-lock.json
index 8c88a71..a30d2d1 100644
--- a/nodejs/package-lock.json
+++ b/nodejs/package-lock.json
@@ -18,6 +18,7 @@
         "bootstrap": "^5.3.8",
         "ejs": "^6.0.1",
         "express": "^5.2.1",
+        "express-rate-limit": "^8.5.2",
         "extend": "^3.0.2",
         "jq-repeat": "^2.0.1",
         "jquery": "^4.0.0",
@@ -917,6 +918,24 @@
         "url": "https://opencollective.com/express"
       }
     },
+    "node_modules/express-rate-limit": {
+      "version": "8.5.2",
+      "resolved": "https://registry.npmjs.org/express-rate-limit/-/express-rate-limit-8.5.2.tgz",
+      "integrity": "sha512-5Kb34ipNX694DH48vN9irak1Qx30nb0PLYHXfJgw4YEjiC3ZEmZJhwOp+VfiCYwFzvFTdB9QkArYS5kXa2cx2A==",
+      "license": "MIT",
+      "dependencies": {
+        "ip-address": "^10.2.0"
+      },
+      "engines": {
+        "node": ">= 16"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/express-rate-limit"
+      },
+      "peerDependencies": {
+        "express": ">= 4.11"
+      }
+    },
     "node_modules/extend": {
       "version": "3.0.2",
       "resolved": "https://registry.npmjs.org/extend/-/extend-3.0.2.tgz",
@@ -1229,6 +1248,15 @@
       "integrity": "sha512-k/vGaX4/Yla3WzyMCvTQOXYeIHvqOKtnqBduzTHpzpQZzAskKMhZ2K+EnBiSM9zGSoIFeMpXKxa4dYeZIQqewQ==",
       "license": "ISC"
     },
+    "node_modules/ip-address": {
+      "version": "10.2.0",
+      "resolved": "https://registry.npmjs.org/ip-address/-/ip-address-10.2.0.tgz",
+      "integrity": "sha512-/+S6j4E9AHvW9SWMSEY9Xfy66O5PWvVEJ08O0y5JGyEKQpojb0K0GKpz/v5HJ/G0vi3D2sjGK78119oXZeE0qA==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 12"
+      }
+    },
     "node_modules/ipaddr.js": {
       "version": "1.9.1",
       "resolved": "https://registry.npmjs.org/ipaddr.js/-/ipaddr.js-1.9.1.tgz",
diff --git a/nodejs/package.json b/nodejs/package.json
index 0ba5ba2..88669bd 100644
--- a/nodejs/package.json
+++ b/nodejs/package.json
@@ -11,10 +11,10 @@
   "scripts": {
     "start": "node ./bin/www",
     "dev": "npx nodemon --ignore public/ ./bin/www",
-    "test": "node --test test/unit/callback_queue.test.js test/unit/host_lookup.test.js test/unit/wildcard_matchany.test.js test/unit/unix_socket.test.js test/integration/dns_provider.test.js",
-    "test:unit": "node --test test/unit/callback_queue.test.js test/unit/host_lookup.test.js test/unit/wildcard_matchany.test.js test/unit/unix_socket.test.js",
+    "test": "node --test test/unit/callback_queue.test.js test/unit/host_lookup.test.js test/unit/wildcard_matchany.test.js test/unit/roles.test.js test/unit/oidc.test.js test/unit/safe_redirect.test.js test/unit/unix_socket.test.js test/integration/dns_provider.test.js",
+    "test:unit": "node --test test/unit/callback_queue.test.js test/unit/host_lookup.test.js test/unit/wildcard_matchany.test.js test/unit/roles.test.js test/unit/oidc.test.js test/unit/safe_redirect.test.js test/unit/unix_socket.test.js",
     "test:integration": "node --test test/integration/dns_provider.test.js",
-    "test:watch": "node --test --watch test/unit/callback_queue.test.js test/unit/host_lookup.test.js test/unit/wildcard_matchany.test.js test/unit/unix_socket.test.js test/integration/dns_provider.test.js"
+    "test:watch": "node --test --watch test/unit/callback_queue.test.js test/unit/host_lookup.test.js test/unit/wildcard_matchany.test.js test/unit/roles.test.js test/unit/oidc.test.js test/unit/safe_redirect.test.js test/unit/unix_socket.test.js test/integration/dns_provider.test.js"
   },
   "engines": {
     "node": ">=18.0.0"
@@ -29,6 +29,7 @@
     "bootstrap": "^5.3.8",
     "ejs": "^6.0.1",
     "express": "^5.2.1",
+    "express-rate-limit": "^8.5.2",
     "extend": "^3.0.2",
     "jq-repeat": "^2.0.1",
     "jquery": "^4.0.0",
diff --git a/nodejs/public/lib/js/app-base.js b/nodejs/public/lib/js/app-base.js
index ba4880d..3a7b153 100644
--- a/nodejs/public/lib/js/app-base.js
+++ b/nodejs/public/lib/js/app-base.js
@@ -76,7 +76,7 @@ app.api = (function(app){
 	var baseURL = '/api/'
 
 	function post(url, data, callback){
-		if(!$.isFunction(callback)) callback = callback2;
+		if(typeof callback !== 'function') callback = callback2;
 		return $.ajax({
 			type: 'POST',
 			url: baseURL+url,
@@ -97,7 +97,7 @@ app.api = (function(app){
 	}
 
 	function put(url, data, callback){
-		if(!$.isFunction(callback)) callback = callback2;
+		if(typeof callback !== 'function') callback = callback2;
 		return $.ajax({
 			type: 'PUT',
 			url: baseURL+url,
@@ -118,7 +118,7 @@ app.api = (function(app){
 	}
 
 	function remove(url, callback, callback2){
-		if(!$.isFunction(callback)) callback = callback2;
+		if(typeof callback !== 'function') callback = callback2;
 		return $.ajax({
 			type: 'delete',
 			url: baseURL+url,
@@ -191,7 +191,8 @@ app.auth = (function(app){
 	function isLoggedIn(callback){
 		if(getToken()){
 			return app.api.get('user/me', function(error, data){
-				if(!error) app.auth.user = data;
+				// data now carries effective rights (isAdmin, global, domains).
+				if(!error) app.auth.user = app.auth.perms = data;
 				return callback(error, data);
 			});
 		}else{
@@ -199,6 +200,41 @@ app.auth = (function(app){
 		}
 	}
 
+	// Constrain a redirect target to a same-origin absolute path. Rejects
+	// absolute URLs (open redirect), protocol-relative "//host" and "/\host",
+	// and non-path schemes like "javascript:" (XSS). Falls back to "/".
+	function safeInternalPath(path){
+		if(typeof path !== 'string' || path.charAt(0) !== '/'
+				|| path.charAt(1) === '/' || path.charAt(1) === '\\'){
+			return '/';
+		}
+		return path;
+	}
+
+	// Consume an app token handed back by the OIDC callback via the URL
+	// fragment (#token=…&redirect=…). Stores it, strips the fragment, and
+	// forwards to the intended page. Returns true if a token was consumed.
+	function consumeTokenFragment(){
+		if(!location.hash) return false;
+		var params = new URLSearchParams(location.hash.replace(/^#/, ''));
+		var token = params.get('token');
+		if(!token) return false;
+
+		setToken(token);
+		// redirect comes from the URL fragment (attacker-controllable); only
+		// allow a same-origin path so it can't become an open redirect / XSS.
+		var redirect = safeInternalPath(params.get('redirect') || '/');
+		// Drop the token from the address bar before navigating on.
+		history.replaceState(null, '', location.pathname + location.search);
+		window.location.href = redirect;
+		return true;
+	}
+
+	// True when the logged-in user is a global admin (per user/me).
+	function isAdmin(){
+		return !!(app.auth.perms && app.auth.perms.isAdmin);
+	}
+
 	function logIn(args, callback){
 		app.api.post('auth/login', args, function(error, data){
 			if(data.login){
@@ -214,25 +250,27 @@ app.auth = (function(app){
 	}
 
 	function forceLogin(){
-		$.holdReady(true);
+		// jQuery 4 removed $.holdReady; rely on the redirect below to keep an
+		// unauthenticated user off the page instead of pausing document ready.
 		app.auth.isLoggedIn(function(error, isLoggedIn){
 			if(error || !isLoggedIn){
 				app.auth.logOut(function(){})
 				location.replace(`/login${location.href.replace(location.origin, '')}`);
-			}else{
-				$.holdReady(false);
 			}
 		});
 	}
 
 	function logInRedirect(){
-		window.location.href = location.href.replace(location.origin+'/login', '') || '/'
+		window.location.href = safeInternalPath(location.href.replace(location.origin+'/login', '') || '/')
 	}
 
 	return {
 		getToken: getToken,
 		setToken: setToken,
 		isLoggedIn: isLoggedIn,
+		consumeTokenFragment: consumeTokenFragment,
+		isAdmin: isAdmin,
+		perms: null,
 		logIn: logIn,
 		logOut: logOut,
 		forceLogin,
@@ -270,6 +308,29 @@ app.user = (function(app){
 
 })(app);
 
+app.grant = (function(app){
+	function list(callback){
+		app.api.get('grant/', function(error, data){
+			callback(error, data);
+		});
+	}
+
+	function add(args, callback){
+		app.api.post('grant/', args, function(error, data){
+			callback(error, data);
+		});
+	}
+
+	function remove(id, callback){
+		app.api.delete('grant/' + encodeURIComponent(id), function(error, data){
+			callback(error, data);
+		});
+	}
+
+	return {list, add, remove};
+
+})(app);
+
 app.util = (function(app){
 
 	function getUrlParameter(name){
diff --git a/nodejs/routes/api.js b/nodejs/routes/api.js
index 877906f..3b92587 100644
--- a/nodejs/routes/api.js
+++ b/nodejs/routes/api.js
@@ -3,14 +3,18 @@
 const router = require('express').Router();
 const conf = require('@simpleworkjs/conf');
 const middleware = require('../middleware/auth');
+const authz = require('../middleware/authz');
 
-// API routes for authentication. 
+// API routes for authentication.
 router.use('/auth',  require('./auth'));
 
 // API routes for working with users. All endpoints need to be have valid user.
+// User management is admin-only; the router allows self-service exceptions
+// (GET /me, PUT /password) before its own admin gate.
 router.use('/user', middleware.auth, require('./user'));
 
 // API routes for working with hosts. All endpoints need to be have valid user.
+// Per-domain authorization is enforced inside the host router.
 router.use('/host', middleware.auth, require('./host'));
 
 router.use('/dns', middleware.auth, require('./dns'));
@@ -18,4 +22,7 @@ router.use('/dns', middleware.auth, require('./dns'));
 // API routes for working with hosts. All endpoints need to be have valid user.
 router.use('/cert', middleware.auth, require('./cert'));
 
+// Grant management (who can manage which domains) is global-admin-only.
+router.use('/grant', middleware.auth, authz.requireAdmin, require('./grant'));
+
 module.exports = router;
\ No newline at end of file
diff --git a/nodejs/routes/auth.js b/nodejs/routes/auth.js
index 4b0bef8..9e40523 100755
--- a/nodejs/routes/auth.js
+++ b/nodejs/routes/auth.js
@@ -1,10 +1,25 @@
 'use strict';
 
 const router = require('express').Router();
+const { rateLimit } = require('express-rate-limit');
+const conf = require('@simpleworkjs/conf');
 const { Auth } = require('../models/auth');
+const { OidcState } = require('../models/oidc_state');
+const oidc = require('../utils/oidc');
+const { safeInternalPath } = require('../utils/safe_redirect');
+
+// Throttle unauthenticated auth endpoints (credential login + the OIDC
+// handshake) to blunt brute-force / callback abuse. Keyed per IP.
+const authLimiter = rateLimit({
+	windowMs: 15 * 60 * 1000,   // 15 minutes
+	max: 60,                    // 60 attempts per IP per window
+	standardHeaders: true,
+	legacyHeaders: false,
+	message: {name: 'TooManyRequests', message: 'Too many attempts, please try again later.'},
+});
 
 
-router.post('/login', async function(req, res, next){
+router.post('/login', authLimiter, async function(req, res, next){
 	try{
 		let auth = await Auth.login(req.body);
 		return res.json({
@@ -29,4 +44,68 @@ router.all('/logout', async function(req, res, next){
 	}
 });
 
+/**
+ * OIDC login start: create a PKCE + state challenge, persist it (auto-expiring
+ * via OidcState TTL), and redirect the browser to the SSO authorize endpoint.
+ */
+router.get('/oidc/start', authLimiter, async function(req, res, next){
+	try{
+		if(!conf.oidc || !conf.oidc.enabled){
+			let error = new Error('OidcDisabled');
+			error.status = 404;
+			error.message = 'OIDC login is not enabled.';
+			throw error;
+		}
+
+		let {state, codeVerifier, codeChallenge} = oidc.createAuthRequest();
+		await OidcState.create({
+			state,
+			codeVerifier,
+			// Sanitize now so a hostile ?redirect= can't be stored and later
+			// reflected into the login page's navigation.
+			redirect: safeInternalPath(req.query.redirect || '/'),
+		});
+
+		return res.redirect(oidc.buildAuthUrl(state, codeChallenge));
+	}catch(error){
+		next(error);
+	}
+});
+
+/**
+ * OIDC callback: validate state (consuming the one-time record), exchange the
+ * code for tokens, read identity from userinfo, establish a session, and hand
+ * the app token back to the browser via a URL fragment for the login page to
+ * store in localStorage.
+ */
+router.get('/oidc/callback', authLimiter, async function(req, res, next){
+	try{
+		let {code, state} = req.query;
+		if(!code || !state){
+			let error = new Error('OidcCallbackInvalid');
+			error.status = 400;
+			error.message = 'Missing code or state.';
+			throw error;
+		}
+
+		// get() throws if the state is unknown or has expired — this both binds
+		// the callback to our request and bounds replay.
+		let saved = await OidcState.get(state);
+		await saved.remove();
+
+		let tokens = await oidc.exchangeCode(code, saved.codeVerifier);
+		let claims = await oidc.fetchUserInfo(tokens.access_token);
+		let identity = oidc.claimsToIdentity(claims);
+
+		let {token} = await Auth.oidcSession(identity);
+
+		let redirect = safeInternalPath(saved.redirect || '/');
+		return res.redirect(
+			`/login#token=${encodeURIComponent(token.token)}&redirect=${encodeURIComponent(redirect)}`
+		);
+	}catch(error){
+		next(error);
+	}
+});
+
 module.exports = router;
diff --git a/nodejs/routes/cert.js b/nodejs/routes/cert.js
index 40db330..b10e972 100644
--- a/nodejs/routes/cert.js
+++ b/nodejs/routes/cert.js
@@ -2,9 +2,10 @@
 
 const router = require('express').Router();
 const {getCert} = require('../models/cert');
+const authz = require('../middleware/authz');
 
 
-router.get('/:host', async function(req, res, next){
+router.get('/:host', authz.requireDomainRole('viewer', req => req.params.host), async function(req, res, next){
 	try{
 		return res.json(await getCert(req.params.host));
 	}catch(error){
diff --git a/nodejs/routes/dns.js b/nodejs/routes/dns.js
index 6fdedc4..ee8a48f 100644
--- a/nodejs/routes/dns.js
+++ b/nodejs/routes/dns.js
@@ -2,10 +2,14 @@
 
 const router = require('express').Router();
 const {DnsProvider, Domain} = require('../models').models;
+const authz = require('../middleware/authz');
 
 const Model = DnsProvider;
 
-router.get('/', async function(req, res, next){
+// Provider listing exposes credentials/config for every domain, so it is
+// admin-only. The creator of a provider still owns its domains (via created_by)
+// and manages hosts/records under them without being a global admin.
+router.get('/', authz.requireAdmin, async function(req, res, next){
 	try{
 		return res.json({
 			results:  await Model[req.query.detail ? "listDetail" : "list"]()
@@ -15,7 +19,7 @@ router.get('/', async function(req, res, next){
 	}
 });
 
-router.options('/', async function(req, res, next){
+router.options('/', authz.requireAdmin, async function(req, res, next){
 	try{
 		return res.json({
 			results:  await Model.listProviders()
@@ -25,9 +29,9 @@ router.options('/', async function(req, res, next){
 	}
 });
 
-router.post('/', async function(req, res, next){
+router.post('/', authz.requireAdmin, async function(req, res, next){
 	try{
-		req.body.created_by = req.user.username;
+		req.body.created_by = authz.reqUsername(req);
 		let item = await Model.create(req.body);
 
 		return res.json({
@@ -41,15 +45,19 @@ router.post('/', async function(req, res, next){
 
 router.get('/domain', async function(req, res, next){
 	try{
-		return res.json({
-			results:  await Domain[req.query.detail ? "listDetail" : "list"]()
-		});
+		let results = await Domain[req.query.detail ? "listDetail" : "list"]();
+
+		// Only surface domains the caller may view.
+		results = await authz.filterViewable(req, results,
+			item => (typeof item === 'string' ? item : item.domain));
+
+		return res.json({results});
 	}catch(error){
 		return next(error);
 	}
 });
 
-router.post('/domain/refresh/:item', async function(req, res, next){
+router.post('/domain/refresh/:item', authz.requireAdmin, async function(req, res, next){
 	try{
 		let item = await Model.get(req.params.item);
 		return res.json({results: await item.updateDomains()});
@@ -58,7 +66,7 @@ router.post('/domain/refresh/:item', async function(req, res, next){
 	}
 })
 
-router.get('/domain/:item', async function(req, res, next){
+router.get('/domain/:item', authz.requireDomainRole('viewer', authz.resolve.domainParam), async function(req, res, next){
 	try{
 		return res.json({
 			results:  [await Domain.get(req.params.item)]
@@ -68,7 +76,7 @@ router.get('/domain/:item', async function(req, res, next){
 	}
 });
 
-router.get('/:item', async function(req, res, next){
+router.get('/:item', authz.requireAdmin, async function(req, res, next){
 	try{
 
 		return res.json({
@@ -80,9 +88,9 @@ router.get('/:item', async function(req, res, next){
 	}
 });
 
-router.put('/:item', async function(req, res, next){
+router.put('/:item', authz.requireAdmin, async function(req, res, next){
 	try{
-		req.body.updated_by = req.user.username;
+		req.body.updated_by = authz.reqUsername(req);
 		let item = await Model.get(req.params.item);
 		item = await item.update(req.body);
 
@@ -98,7 +106,7 @@ router.put('/:item', async function(req, res, next){
 	}
 });
 
-router.delete('/:item', async function(req, res, next){
+router.delete('/:item', authz.requireAdmin, async function(req, res, next){
 	try{
 		let item = await Model.get(req.params.item);
 		let count = await item.remove();
diff --git a/nodejs/routes/grant.js b/nodejs/routes/grant.js
new file mode 100644
index 0000000..85b317f
--- /dev/null
+++ b/nodejs/routes/grant.js
@@ -0,0 +1,42 @@
+'use strict';
+
+const router = require('express').Router();
+const {Grant} = require('../models/grant');
+const {reqUsername} = require('../middleware/authz');
+
+// All grant management is admin-only; the gate is applied where this router is
+// mounted (routes/api.js).
+
+router.get('/', async function(req, res, next){
+	try{
+		return res.json({results: await Grant.listDetail()});
+	}catch(error){
+		next(error);
+	}
+});
+
+router.post('/', async function(req, res, next){
+	try{
+		req.body.created_by = reqUsername(req);
+		let grant = await Grant.create(req.body);
+		return res.json({
+			message: `Granted ${req.body.role} to ${req.body.subjectType} "${req.body.subject}"` +
+				(req.body.scope === 'global' ? ' globally.' : ` on ${req.body.domain}.`),
+			...grant,
+		});
+	}catch(error){
+		next(error);
+	}
+});
+
+router.delete('/:id', async function(req, res, next){
+	try{
+		let grant = await Grant.get(req.params.id);
+		await grant.remove();
+		return res.json({message: `Grant ${req.params.id} removed.`});
+	}catch(error){
+		next(error);
+	}
+});
+
+module.exports = router;
diff --git a/nodejs/routes/host.js b/nodejs/routes/host.js
index 1d6e86c..ec25313 100755
--- a/nodejs/routes/host.js
+++ b/nodejs/routes/host.js
@@ -2,22 +2,28 @@
 
 const router = require('express').Router();
 const {Host, Domain} = require('../models').models;
+const authz = require('../middleware/authz');
 
 const Model = Host;
 
 router.get('/', async function(req, res, next){
 	try{
-		return res.json({
-			results: await Model[req.query.detail ? "listDetail" : "list"](),
-		});
+		let results = await Model[req.query.detail ? "listDetail" : "list"]();
+
+		// Restrict to hosts whose domain the caller may view. list() yields host
+		// strings; listDetail() yields instances with a .host.
+		results = await authz.filterViewable(req, results,
+			item => (typeof item === 'string' ? item : item.host));
+
+		return res.json({results});
 	}catch(error){
 		return next(error);
 	}
 });
 
-router.post('/', async function(req, res, next){
+router.post('/', authz.requireDomainRole('manager', authz.resolve.hostBody), async function(req, res, next){
 	try{
-		req.body.created_by = req.user.username;
+		req.body.created_by = authz.reqUsername(req);
 		let item = await Model.create(req.body);
 
 		return res.json({
@@ -29,7 +35,7 @@ router.post('/', async function(req, res, next){
 	}
 });
 
-router.get('/lookup/:item', async function(req, res, next){
+router.get('/lookup/:item', authz.requireDomainRole('viewer', authz.resolve.hostParam), async function(req, res, next){
 	try{
 		return res.json({
 			string: req.params.item,
@@ -41,7 +47,8 @@ router.get('/lookup/:item', async function(req, res, next){
 	}
 });
 
-router.get('/lookupobj', async function(req, res, next){
+// The full lookup tree exposes every host, so restrict it to admins.
+router.get('/lookupobj', authz.requireAdmin, async function(req, res, next){
 	try{
 		return res.json({
 			results: Model.lookUpObj,
@@ -52,7 +59,7 @@ router.get('/lookupobj', async function(req, res, next){
 	}
 });
 
-router.delete('/cache', async function(req, res, next){
+router.delete('/cache', authz.requireAdmin, async function(req, res, next){
 	try{
 		let count = await Model.clearCache();
 
@@ -65,7 +72,7 @@ router.delete('/cache', async function(req, res, next){
 	}
 });
 
-router.get('/:item', async function(req, res, next){
+router.get('/:item', authz.requireDomainRole('viewer', authz.resolve.hostParam), async function(req, res, next){
 	try{
 
 		return res.json({
@@ -77,9 +84,9 @@ router.get('/:item', async function(req, res, next){
 	}
 });
 
-router.put('/:item', async function(req, res, next){
+router.put('/:item', authz.requireDomainRole('manager', authz.resolve.hostParam), async function(req, res, next){
 	try{
-		req.body.updated_by = req.user.username;
+		req.body.updated_by = authz.reqUsername(req);
 		let item = await Model.get(req.params.item);
 		item = await item.update(req.body);
 
@@ -95,7 +102,7 @@ router.put('/:item', async function(req, res, next){
 	}
 });
 
-router.delete('/:item', async function(req, res, next){
+router.delete('/:item', authz.requireDomainRole('manager', authz.resolve.hostParam), async function(req, res, next){
 	try{
 		let item = await Model.get(req.params.item);
 		let count = await item.remove();
@@ -110,7 +117,7 @@ router.delete('/:item', async function(req, res, next){
 	}
 });
 
-router.put('/:item/renew', async function(req, res, next){
+router.put('/:item/renew', authz.requireDomainRole('manager', authz.resolve.hostParam), async function(req, res, next){
 	try{
 		let item = await Model.get(req.params.item);
 		item.createWildcardCert();
diff --git a/nodejs/routes/render.js b/nodejs/routes/render.js
index 86bacb8..d98fd5d 100644
--- a/nodejs/routes/render.js
+++ b/nodejs/routes/render.js
@@ -42,6 +42,15 @@ router.get('/users', async function(req, res, next) {
   res.render('users', {...values});
 });
 
+router.get('/grants', async function(req, res, next) {
+  res.render('grants', {...values});
+});
+
+// Bare /login (the OIDC callback redirect target) and /login/<path>.
+router.get('/login', async function(req, res, next) {
+  res.render('login', {...values, redirect: req.query.redirect});
+});
+
 router.get('/login/*splat', async function(req, res, next) {
   res.render('login', {...values, redirect: req.query.redirect});
 });
diff --git a/nodejs/routes/user.js b/nodejs/routes/user.js
index 04d1dc8..7530d73 100755
--- a/nodejs/routes/user.js
+++ b/nodejs/routes/user.js
@@ -1,9 +1,14 @@
 'use strict';
 
 const router = require('express').Router();
-const {User} = require('../models').models; 
+const {User} = require('../models').models;
+const authz = require('../middleware/authz');
 
-router.get('/', async function(req, res, next){
+// User management is global-admin-only, except the self-service routes below
+// (GET /me, PUT /password, POST /key) which any authenticated user may call for
+// their own account.
+
+router.get('/', authz.requireAdmin, async function(req, res, next){
 	try{
 		return res.json({
 			results:  await User[req.query.detail ? "listDetail" : "list"]()
@@ -13,9 +18,9 @@ router.get('/', async function(req, res, next){
 	}
 });
 
-router.post('/', async function(req, res, next){
+router.post('/', authz.requireAdmin, async function(req, res, next){
 	try{
-		req.body.created_by = req.user.username
+		req.body.created_by = authz.reqUsername(req)
 
 		return res.json(await User.add(req.body));
 	}catch(error){
@@ -23,7 +28,7 @@ router.post('/', async function(req, res, next){
 	}
 });
 
-router.delete('/:username', async function(req, res, next){
+router.delete('/:username', authz.requireAdmin, async function(req, res, next){
 	try{
 		let user = await User.get(req.params.username);
 
@@ -33,14 +38,24 @@ router.delete('/:username', async function(req, res, next){
 	}
 });
 
+// Self-service: the caller's own identity and effective rights. Drives the
+// frontend's nav/button gating.
 router.get('/me', async function(req, res, next){
 	try{
-		return res.json({username: req.user.username});
+		let effective = await authz.getEffective(req);
+		return res.json({
+			username: authz.reqUsername(req),
+			groups: req.groups || [],
+			isAdmin: effective.isAdmin,
+			global: effective.global,
+			domains: effective.domains,
+		});
 	}catch(error){
 		next(error);
 	}
 });
 
+// Self-service: change your own password.
 router.put('/password', async function(req, res, next){
 	try{
 		return res.json({results: await req.user.setPassword(req.body)})
@@ -49,7 +64,8 @@ router.put('/password', async function(req, res, next){
 	}
 });
 
-router.put('/password/:username', async function(req, res, next){
+// Admin: reset another user's password.
+router.put('/password/:username', authz.requireAdmin, async function(req, res, next){
 	try{
 		let user = await User.get(req.params.username);
 		return res.json({results: await user.setPassword(req.body)});
@@ -58,7 +74,7 @@ router.put('/password/:username', async function(req, res, next){
 	}
 });
 
-router.post('/invite', async function(req, res, next){
+router.post('/invite', authz.requireAdmin, async function(req, res, next){
 	try{
 		let token = await req.user.invite();
 
@@ -68,10 +84,11 @@ router.post('/invite', async function(req, res, next){
 	}
 });
 
+// Self-service: add an SSH key to your own account.
 router.post('/key', async function(req, res, next){
 	try{
 		let added = await User.addSSHkey({
-			username: req.user.username,
+			username: authz.reqUsername(req),
 			key: req.body.key
 		});
 
diff --git a/nodejs/test/unit/oidc.test.js b/nodejs/test/unit/oidc.test.js
new file mode 100644
index 0000000..9de3f9f
--- /dev/null
+++ b/nodejs/test/unit/oidc.test.js
@@ -0,0 +1,77 @@
+'use strict';
+
+const {describe, test} = require('node:test');
+const assert = require('node:assert');
+const crypto = require('crypto');
+
+const oidc = require('../../utils/oidc');
+const conf = require('@simpleworkjs/conf');
+
+/**
+ * Tests for the pure parts of the OIDC client (utils/oidc): PKCE/state
+ * generation, authorize-URL construction, and claim mapping. Network calls
+ * (exchangeCode/fetchUserInfo) are not exercised here.
+ */
+
+describe('oidc PKCE / state', () => {
+	test('createAuthRequest returns distinct high-entropy state and verifier', () => {
+		const a = oidc.createAuthRequest();
+		assert.ok(a.state.length >= 20);
+		assert.ok(a.codeVerifier.length >= 20);
+		assert.notStrictEqual(a.state, a.codeVerifier);
+
+		const b = oidc.createAuthRequest();
+		assert.notStrictEqual(a.state, b.state);
+	});
+
+	test('code challenge is the base64url S256 of the verifier', () => {
+		const {codeVerifier, codeChallenge} = oidc.createAuthRequest();
+		const expected = crypto.createHash('sha256').update(codeVerifier).digest('base64')
+			.replace(/\+/g, '-').replace(/\//g, '_').replace(/=+$/, '');
+		assert.strictEqual(codeChallenge, expected);
+	});
+
+	test('challenge is base64url (no +, /, or = padding)', () => {
+		const {codeChallenge} = oidc.createAuthRequest();
+		assert.ok(!/[+/=]/.test(codeChallenge));
+	});
+});
+
+describe('oidc buildAuthUrl', () => {
+	test('includes required authorization-code + PKCE params', () => {
+		const url = new URL(oidc.buildAuthUrl('the-state', 'the-challenge'));
+		assert.strictEqual(url.origin + url.pathname, conf.oidc.authorizationEndpoint);
+		const p = url.searchParams;
+		assert.strictEqual(p.get('response_type'), 'code');
+		assert.strictEqual(p.get('client_id'), conf.oidc.clientId);
+		assert.strictEqual(p.get('redirect_uri'), conf.oidc.redirectUri);
+		assert.strictEqual(p.get('state'), 'the-state');
+		assert.strictEqual(p.get('code_challenge'), 'the-challenge');
+		assert.strictEqual(p.get('code_challenge_method'), 'S256');
+		assert.ok(p.get('scope').includes('openid'));
+		assert.ok(p.get('scope').includes('groups'));
+	});
+});
+
+describe('oidc claimsToIdentity', () => {
+	test('maps preferred_username and groups', () => {
+		const id = oidc.claimsToIdentity({
+			sub: 'abc',
+			preferred_username: 'jane',
+			groups: ['dns-team', 'proxy-admins'],
+		});
+		assert.strictEqual(id.username, 'jane');
+		assert.deepStrictEqual(id.groups, ['dns-team', 'proxy-admins']);
+	});
+
+	test('falls back to sub when no preferred_username', () => {
+		const id = oidc.claimsToIdentity({sub: 'abc'});
+		assert.strictEqual(id.username, 'abc');
+		assert.deepStrictEqual(id.groups, []);
+	});
+
+	test('coerces a single group value to an array', () => {
+		const id = oidc.claimsToIdentity({sub: 'abc', groups: 'solo'});
+		assert.deepStrictEqual(id.groups, ['solo']);
+	});
+});
diff --git a/nodejs/test/unit/roles.test.js b/nodejs/test/unit/roles.test.js
new file mode 100644
index 0000000..eb0c025
--- /dev/null
+++ b/nodejs/test/unit/roles.test.js
@@ -0,0 +1,173 @@
+'use strict';
+
+const {describe, test} = require('node:test');
+const assert = require('node:assert');
+
+const roles = require('../../utils/roles');
+
+/**
+ * Tests for the pure authorization logic (utils/roles). No redis: grant rows,
+ * owned domains, and conf.auth are passed in directly. This is the heart of the
+ * per-domain rights model — see models/grant.js for the redis-backed wiring.
+ */
+
+const authConf = {
+	adminUsers: ['root'],
+	adminGroups: ['proxy-admins'],
+	groupRoleMap: {
+		'global-viewers': {scope: 'global', role: 'viewer'},
+		'foo-managers': {scope: 'domain', domain: 'foo.com', role: 'manager'},
+		'super': {scope: 'global', role: 'admin'},
+	},
+};
+
+const effective = (identity, data) =>
+	roles.resolveEffective(identity, {authConf, ...data});
+
+describe('roles.resolveEffective', () => {
+
+	describe('admin', () => {
+		test('conf adminUsers grants global admin', () => {
+			const e = effective({username: 'root', groups: []});
+			assert.strictEqual(e.isAdmin, true);
+		});
+
+		test('conf adminGroups grants global admin', () => {
+			const e = effective({username: 'bob', groups: ['proxy-admins']});
+			assert.strictEqual(e.isAdmin, true);
+		});
+
+		test('groupRoleMap admin role grants global admin', () => {
+			const e = effective({username: 'bob', groups: ['super']});
+			assert.strictEqual(e.isAdmin, true);
+		});
+
+		test('a global admin Grant record grants admin', () => {
+			const e = effective({username: 'bob', groups: []}, {
+				grants: [{subjectType: 'user', subject: 'bob', scope: 'global', role: 'admin'}],
+			});
+			assert.strictEqual(e.isAdmin, true);
+		});
+
+		test('admin passes every domain check', () => {
+			const e = effective({username: 'root', groups: []});
+			assert.strictEqual(roles.allows(e, 'manager', 'anything.com'), true);
+			assert.strictEqual(roles.roleForDomain(e, 'anything.com'), 'admin');
+		});
+
+		test('a plain user is not admin', () => {
+			const e = effective({username: 'nobody', groups: []});
+			assert.strictEqual(e.isAdmin, false);
+		});
+	});
+
+	describe('per-domain grants', () => {
+		test('user manager grant allows manage on that domain only', () => {
+			const e = effective({username: 'jane', groups: []}, {
+				grants: [{subjectType: 'user', subject: 'jane', scope: 'domain', domain: 'ex.com', role: 'manager'}],
+			});
+			assert.strictEqual(roles.allows(e, 'manager', 'ex.com'), true);
+			assert.strictEqual(roles.allows(e, 'viewer', 'ex.com'), true);
+			assert.strictEqual(roles.allows(e, 'manager', 'other.com'), false);
+			assert.strictEqual(roles.allows(e, 'viewer', 'other.com'), false);
+		});
+
+		test('viewer grant allows read but not manage', () => {
+			const e = effective({username: 'jane', groups: []}, {
+				grants: [{subjectType: 'user', subject: 'jane', scope: 'domain', domain: 'ex.com', role: 'viewer'}],
+			});
+			assert.strictEqual(roles.allows(e, 'viewer', 'ex.com'), true);
+			assert.strictEqual(roles.allows(e, 'manager', 'ex.com'), false);
+		});
+
+		test('group grant applies to members', () => {
+			const e = effective({username: 'jane', groups: ['dns-team']}, {
+				grants: [{subjectType: 'group', subject: 'dns-team', scope: 'domain', domain: 'ex.com', role: 'manager'}],
+			});
+			assert.strictEqual(roles.allows(e, 'manager', 'ex.com'), true);
+		});
+
+		test('group grant does not apply to non-members', () => {
+			const e = effective({username: 'jane', groups: []}, {
+				grants: [{subjectType: 'group', subject: 'dns-team', scope: 'domain', domain: 'ex.com', role: 'manager'}],
+			});
+			assert.strictEqual(roles.allows(e, 'viewer', 'ex.com'), false);
+		});
+
+		test('groupRoleMap domain default applies', () => {
+			const e = effective({username: 'jane', groups: ['foo-managers']});
+			assert.strictEqual(roles.allows(e, 'manager', 'foo.com'), true);
+			assert.strictEqual(roles.allows(e, 'manager', 'bar.com'), false);
+		});
+	});
+
+	describe('override precedence (strongest wins)', () => {
+		test('a per-user manager grant beats a group viewer grant', () => {
+			const e = effective({username: 'jane', groups: ['team']}, {
+				grants: [
+					{subjectType: 'group', subject: 'team', scope: 'domain', domain: 'ex.com', role: 'viewer'},
+					{subjectType: 'user', subject: 'jane', scope: 'domain', domain: 'ex.com', role: 'manager'},
+				],
+			});
+			assert.strictEqual(roles.roleForDomain(e, 'ex.com'), 'manager');
+		});
+
+		test('grant order does not matter (max wins)', () => {
+			const e = effective({username: 'jane', groups: []}, {
+				grants: [
+					{subjectType: 'user', subject: 'jane', scope: 'domain', domain: 'ex.com', role: 'manager'},
+					{subjectType: 'user', subject: 'jane', scope: 'domain', domain: 'ex.com', role: 'viewer'},
+				],
+			});
+			assert.strictEqual(roles.roleForDomain(e, 'ex.com'), 'manager');
+		});
+	});
+
+	describe('ownership', () => {
+		test('owned domains grant manager without an explicit grant', () => {
+			const e = effective({username: 'owner', groups: []}, {
+				ownedDomains: ['mine.com'],
+			});
+			assert.strictEqual(roles.roleForDomain(e, 'mine.com'), 'manager');
+			assert.strictEqual(roles.allows(e, 'manager', 'mine.com'), true);
+			assert.strictEqual(roles.allows(e, 'viewer', 'notmine.com'), false);
+		});
+	});
+
+	describe('global (non-admin) roles', () => {
+		test('global viewer sees every domain read-only', () => {
+			const e = effective({username: 'v', groups: ['global-viewers']});
+			assert.strictEqual(e.global, 'viewer');
+			assert.strictEqual(roles.allows(e, 'viewer', 'a.com'), true);
+			assert.strictEqual(roles.allows(e, 'viewer', 'b.com'), true);
+			assert.strictEqual(roles.allows(e, 'manager', 'a.com'), false);
+		});
+	});
+
+	describe('visibleDomains', () => {
+		test('lists domains with at least viewer', () => {
+			const e = effective({username: 'jane', groups: []}, {
+				grants: [
+					{subjectType: 'user', subject: 'jane', scope: 'domain', domain: 'a.com', role: 'viewer'},
+					{subjectType: 'user', subject: 'jane', scope: 'domain', domain: 'b.com', role: 'manager'},
+				],
+			});
+			assert.deepStrictEqual(roles.visibleDomains(e).sort(), ['a.com', 'b.com']);
+		});
+	});
+});
+
+describe('roles.rank / maxRole', () => {
+	test('rank ordering', () => {
+		assert.ok(roles.rank('admin') > roles.rank('manager'));
+		assert.ok(roles.rank('manager') > roles.rank('viewer'));
+		assert.ok(roles.rank('viewer') > roles.rank(null));
+	});
+
+	test('maxRole returns the stronger role', () => {
+		assert.strictEqual(roles.maxRole('viewer', 'manager'), 'manager');
+		assert.strictEqual(roles.maxRole('manager', 'viewer'), 'manager');
+		assert.strictEqual(roles.maxRole(null, 'viewer'), 'viewer');
+		assert.strictEqual(roles.maxRole(null, null), null);
+	});
+});
diff --git a/nodejs/test/unit/safe_redirect.test.js b/nodejs/test/unit/safe_redirect.test.js
new file mode 100644
index 0000000..5a449e0
--- /dev/null
+++ b/nodejs/test/unit/safe_redirect.test.js
@@ -0,0 +1,43 @@
+'use strict';
+
+const {describe, test} = require('node:test');
+const assert = require('node:assert');
+
+const {safeInternalPath} = require('../../utils/safe_redirect');
+
+/**
+ * safeInternalPath guards the OIDC post-login redirect against open-redirect
+ * and script-scheme (XSS) targets. Only same-origin "/path" values pass.
+ */
+describe('safeInternalPath', () => {
+
+	test('allows plain same-origin paths', () => {
+		assert.strictEqual(safeInternalPath('/'), '/');
+		assert.strictEqual(safeInternalPath('/hosts'), '/hosts');
+		assert.strictEqual(safeInternalPath('/dns?x=1'), '/dns?x=1');
+		assert.strictEqual(safeInternalPath('/a/b/c#frag'), '/a/b/c#frag');
+	});
+
+	test('rejects absolute URLs', () => {
+		assert.strictEqual(safeInternalPath('https://evil.com'), '/');
+		assert.strictEqual(safeInternalPath('http://evil.com/x'), '/');
+	});
+
+	test('rejects protocol-relative and backslash host tricks', () => {
+		assert.strictEqual(safeInternalPath('//evil.com'), '/');
+		assert.strictEqual(safeInternalPath('/\\evil.com'), '/');
+	});
+
+	test('rejects script / data schemes', () => {
+		assert.strictEqual(safeInternalPath('javascript:alert(1)'), '/');
+		assert.strictEqual(safeInternalPath('data:text/html,<script>'), '/');
+	});
+
+	test('rejects non-path and non-string input', () => {
+		assert.strictEqual(safeInternalPath('hosts'), '/');       // no leading slash
+		assert.strictEqual(safeInternalPath(''), '/');
+		assert.strictEqual(safeInternalPath(undefined), '/');
+		assert.strictEqual(safeInternalPath(null), '/');
+		assert.strictEqual(safeInternalPath({}), '/');
+	});
+});
diff --git a/nodejs/utils/oidc.js b/nodejs/utils/oidc.js
new file mode 100644
index 0000000..c7c8e3e
--- /dev/null
+++ b/nodejs/utils/oidc.js
@@ -0,0 +1,125 @@
+'use strict';
+
+const crypto = require('crypto');
+const conf = require('@simpleworkjs/conf');
+
+/**
+ * Minimal OpenID Connect authorization-code + PKCE client.
+ *
+ * The SSO publishes no jwks_uri, so we do not verify ID-token signatures;
+ * instead we treat the flow as opaque and read identity from the userinfo
+ * endpoint (the access token is exchanged server-side over TLS). Uses Node's
+ * global fetch (Node 18+) and crypto — no external dependency.
+ *
+ * All endpoints and client config come from conf.oidc (+ clientSecret from
+ * secrets.js, deep-merged by @simpleworkjs/conf).
+ */
+
+const base64url = buf => buf.toString('base64')
+	.replace(/\+/g, '-').replace(/\//g, '_').replace(/=+$/, '');
+
+// A high-entropy random string for `state` / PKCE verifier.
+function randomToken(bytes = 32){
+	return base64url(crypto.randomBytes(bytes));
+}
+
+// PKCE S256 challenge derived from the verifier.
+function codeChallengeS256(verifier){
+	return base64url(crypto.createHash('sha256').update(verifier).digest());
+}
+
+// Generate the {state, codeVerifier, codeChallenge} triple for a new login.
+function createAuthRequest(){
+	let state = randomToken(32);
+	let codeVerifier = randomToken(32);
+	let codeChallenge = codeChallengeS256(codeVerifier);
+	return {state, codeVerifier, codeChallenge};
+}
+
+// Build the SSO authorize URL the browser is redirected to.
+function buildAuthUrl(state, codeChallenge){
+	let o = conf.oidc;
+	let params = new URLSearchParams({
+		response_type: 'code',
+		client_id: o.clientId,
+		redirect_uri: o.redirectUri,
+		scope: (o.scopes || ['openid', 'profile', 'email', 'groups']).join(' '),
+		state,
+		code_challenge: codeChallenge,
+		code_challenge_method: 'S256',
+	});
+	return `${o.authorizationEndpoint}?${params.toString()}`;
+}
+
+// Exchange an authorization code for tokens at the token endpoint.
+async function exchangeCode(code, codeVerifier){
+	let o = conf.oidc;
+	let body = new URLSearchParams({
+		grant_type: 'authorization_code',
+		code,
+		redirect_uri: o.redirectUri,
+		client_id: o.clientId,
+		client_secret: o.clientSecret,
+		code_verifier: codeVerifier,
+	});
+
+	let res = await fetch(o.tokenEndpoint, {
+		method: 'POST',
+		headers: {
+			'Content-Type': 'application/x-www-form-urlencoded',
+			'Accept': 'application/json',
+		},
+		body: body.toString(),
+	});
+
+	if(!res.ok){
+		let text = await res.text().catch(() => '');
+		let error = new Error('OidcTokenExchangeFailed');
+		error.name = 'OidcTokenExchangeFailed';
+		error.message = `Token exchange failed (${res.status}): ${text}`;
+		error.status = 502;
+		throw error;
+	}
+
+	return res.json();
+}
+
+// Fetch the userinfo claims for an access token.
+async function fetchUserInfo(accessToken){
+	let o = conf.oidc;
+	let res = await fetch(o.userinfoEndpoint, {
+		headers: {
+			'Authorization': `Bearer ${accessToken}`,
+			'Accept': 'application/json',
+		},
+	});
+
+	if(!res.ok){
+		let error = new Error('OidcUserInfoFailed');
+		error.name = 'OidcUserInfoFailed';
+		error.message = `Userinfo request failed (${res.status})`;
+		error.status = 502;
+		throw error;
+	}
+
+	return res.json();
+}
+
+// Pull the app username and group list out of userinfo claims per conf.
+function claimsToIdentity(claims){
+	let o = conf.oidc;
+	let username = claims[o.usernameClaim || 'preferred_username'] || claims.sub;
+	let groups = claims[o.groupsClaim || 'groups'] || [];
+	if(!Array.isArray(groups)) groups = [groups].filter(Boolean);
+	return {username, groups, claims};
+}
+
+module.exports = {
+	randomToken,
+	codeChallengeS256,
+	createAuthRequest,
+	buildAuthUrl,
+	exchangeCode,
+	fetchUserInfo,
+	claimsToIdentity,
+};
diff --git a/nodejs/utils/roles.js b/nodejs/utils/roles.js
new file mode 100644
index 0000000..7f35f44
--- /dev/null
+++ b/nodejs/utils/roles.js
@@ -0,0 +1,110 @@
+'use strict';
+
+/**
+ * Pure authorization role logic — no redis, no I/O — so it can be unit tested
+ * in isolation. models/grant.js supplies the data (grant records, owned
+ * domains, conf.auth) and this module collapses it into effective rights and
+ * answers allow/deny questions.
+ *
+ * Roles rank: admin > manager (owner/full over a domain) > viewer.
+ */
+
+const ROLE_RANK = {viewer: 1, manager: 2, admin: 3};
+
+function rank(role){
+	return ROLE_RANK[role] || 0;
+}
+
+// Whichever of two roles is stronger; either may be null/undefined.
+function maxRole(a, b){
+	if(rank(a) >= rank(b)) return a || b || null;
+	return b || a || null;
+}
+
+/**
+ * Collapse config, grants, and ownership into effective rights.
+ *
+ * @param {Object} identity - {username, groups: string[]}
+ * @param {Object} data
+ *   - grants: [{subjectType, subject, scope, domain, role}]
+ *   - ownedDomains: string[] (domains the user owns via created_by)
+ *   - authConf: conf.auth ({adminUsers, adminGroups, groupRoleMap})
+ * @returns {Object} { isAdmin, global: role|null, domains: {domain: role} }
+ */
+function resolveEffective(identity, data){
+	let username = identity && identity.username;
+	let groups = (identity && identity.groups) || [];
+	let grants = (data && data.grants) || [];
+	let ownedDomains = (data && data.ownedDomains) || [];
+	let authConf = (data && data.authConf) || {};
+
+	let result = {isAdmin: false, global: null, domains: {}};
+
+	// 1) Config-driven global admin (anti-lockout bootstrap).
+	if((authConf.adminUsers || []).includes(username)) result.isAdmin = true;
+	for(let g of groups){
+		if((authConf.adminGroups || []).includes(g)) result.isAdmin = true;
+	}
+
+	// 2) Config-driven group role defaults.
+	let groupRoleMap = authConf.groupRoleMap || {};
+	for(let g of groups){
+		let m = groupRoleMap[g];
+		if(!m) continue;
+		if(m.role === 'admin' && (m.scope === 'global' || !m.scope)){
+			result.isAdmin = true;
+		}else if(m.scope === 'global'){
+			result.global = maxRole(result.global, m.role);
+		}else if(m.domain){
+			result.domains[m.domain] = maxRole(result.domains[m.domain], m.role);
+		}
+	}
+
+	// 3) Grant records for this user or any of their groups.
+	for(let grant of grants){
+		let matches = (grant.subjectType === 'user' && grant.subject === username)
+			|| (grant.subjectType === 'group' && groups.includes(grant.subject));
+		if(!matches) continue;
+
+		if(grant.scope === 'global'){
+			if(grant.role === 'admin') result.isAdmin = true;
+			else result.global = maxRole(result.global, grant.role);
+		}else{
+			result.domains[grant.domain] = maxRole(result.domains[grant.domain], grant.role);
+		}
+	}
+
+	// 4) Ownership: manager rights over every owned domain.
+	for(let domain of ownedDomains){
+		result.domains[domain] = maxRole(result.domains[domain], 'manager');
+	}
+
+	return result;
+}
+
+// Effective role on one domain, folding in admin and any global role.
+function roleForDomain(effective, domain){
+	if(effective.isAdmin) return 'admin';
+	return maxRole(effective.global, effective.domains[domain]);
+}
+
+// Does `effective` meet or exceed `minRole` for `domain`?
+function allows(effective, minRole, domain){
+	return rank(roleForDomain(effective, domain)) >= rank(minRole);
+}
+
+// Domain names the identity can at least view (excludes the global-role case,
+// which callers treat as "sees everything").
+function visibleDomains(effective){
+	return Object.keys(effective.domains).filter(d => rank(effective.domains[d]) >= rank('viewer'));
+}
+
+module.exports = {
+	ROLE_RANK,
+	rank,
+	maxRole,
+	resolveEffective,
+	roleForDomain,
+	allows,
+	visibleDomains,
+};
diff --git a/nodejs/utils/safe_redirect.js b/nodejs/utils/safe_redirect.js
new file mode 100644
index 0000000..b1adcce
--- /dev/null
+++ b/nodejs/utils/safe_redirect.js
@@ -0,0 +1,23 @@
+'use strict';
+
+/**
+ * Constrain a post-login redirect target to a same-origin path.
+ *
+ * Rejects anything that could leave the site or execute script:
+ *   - absolute URLs        ("https://evil.com")            -> not a "/" path
+ *   - protocol-relative    ("//evil.com", "/\\evil.com")   -> host takeover
+ *   - scheme targets       ("javascript:...", "data:...")  -> XSS
+ * Anything not a plain "/path" falls back to "/".
+ *
+ * The browser has its own copy of this in public/lib/js/app-base.js; keep the
+ * two in sync.
+ */
+function safeInternalPath(path){
+	if(typeof path !== 'string' || path.charAt(0) !== '/'
+			|| path.charAt(1) === '/' || path.charAt(1) === '\\'){
+		return '/';
+	}
+	return path;
+}
+
+module.exports = {safeInternalPath};
diff --git a/nodejs/views/grants.ejs b/nodejs/views/grants.ejs
new file mode 100644
index 0000000..d82331c
--- /dev/null
+++ b/nodejs/views/grants.ejs
@@ -0,0 +1,138 @@
+<%- include('top') %>
+<script type="text/javascript">
+	// Require login to see this page. The API is admin-only; non-admins get 403s.
+	app.auth.forceLogin();
+</script>
+
+<style type="text/css">
+	label.control-label{
+		font-weight: bold;
+		margin-bottom: 1px;
+	}
+	.card-title{
+		font-weight: bold;
+	}
+</style>
+
+<script type="text/javascript">
+
+	function populateGrants(){
+		app.grant.list(function(error, data){
+			if(error) return app.util.actionMessage(error, $.scope.grants.$this, 'danger');
+			for(let grant of data.results){
+				$.scope.grants.push(grant);
+			}
+		});
+	}
+
+	function removeGrant(id){
+		app.grant.remove(id, function(error, data){
+			if(error) return app.util.actionMessage(error, $.scope.grants.$this, 'danger');
+			$.scope.grants.remove(id);
+		});
+	}
+
+	$(document).ready(function(){
+		populateGrants();
+
+		$.scope.grants.__setTake(function($el, item, list){
+			$el.addClass('bg-danger');
+			$el.fadeOut(1000, function(){ $el.remove(); });
+		});
+	});
+</script>
+
+<div class="row" style="display:none">
+	<div class="col-md-4">
+		<div class="card shadow-lg">
+
+			<div class="card-header text-center">
+				<span class="card-icon float-start">
+					<i class="fa-solid fa-user-shield"></i>
+				</span>
+				<span class="card-title">Add Grant</span>
+			</div>
+
+			<div class="card-header actionMessage" style="display:none"></div>
+			<div class="card-body">
+				<form action="grant/" onsubmit="formAJAX(this)" evalAJAX="
+					$.scope.grants.remove(data.id);
+					$.scope.grants.splice(0, 0, data);
+				">
+					<div class="form-group">
+						<label class="control-label">Subject type</label>
+						<select class="form-control" name="subjectType">
+							<option value="user">User</option>
+							<option value="group">Group</option>
+						</select>
+					</div>
+					<div class="form-group">
+						<label class="control-label">Subject (username or group)</label>
+						<input type="text" class="form-control" name="subject" placeholder="alice or dns-team" />
+					</div>
+					<div class="form-group">
+						<label class="control-label">Scope</label>
+						<select class="form-control" name="scope">
+							<option value="domain">Domain</option>
+							<option value="global">Global</option>
+						</select>
+					</div>
+					<div class="form-group">
+						<label class="control-label">Domain (for domain scope)</label>
+						<input type="text" class="form-control" name="domain" placeholder="example.com" />
+					</div>
+					<div class="form-group">
+						<label class="control-label">Role</label>
+						<select class="form-control" name="role">
+							<option value="viewer">Viewer (read)</option>
+							<option value="manager">Manager (full over domain)</option>
+							<option value="admin">Admin (global only)</option>
+						</select>
+					</div>
+					<hr />
+					<button type="submit" class="btn btn-info">Add Grant</button>
+				</form>
+			</div>
+		</div>
+	</div>
+
+	<div class="col-md-8">
+		<div class="card shadow-lg">
+
+			<div class="card-header text-center">
+				<span class="card-icon float-start">
+					<i class="fa-solid fa-list-check"></i>
+				</span>
+				<span class="card-title">Grants</span>
+			</div>
+
+			<div class="card-header actionMessage" style="display:none"></div>
+			<table class="card-body table table-striped" style="margin-bottom:0">
+				<thead>
+					<th>Type</th>
+					<th>Subject</th>
+					<th>Scope</th>
+					<th>Domain</th>
+					<th>Role</th>
+					<th>Delete</th>
+				</thead>
+				<tbody>
+					<tr jq-repeat="grants" jq-repeat-index="id" style="display:none">
+						<td class="align-middle">{{ subjectType }}</td>
+						<td class="align-middle">{{ subject }}</td>
+						<td class="align-middle">{{ scope }}</td>
+						<td class="align-middle">{{ domain }}</td>
+						<td class="align-middle">{{ role }}</td>
+						<td class="align-middle">
+							<button type="button" class="btn btn-danger" onclick="removeGrant('{{id}}')">
+								<i class="fa-solid fa-trash"></i>
+								Delete
+							</button>
+						</td>
+					</tr>
+				</tbody>
+			</table>
+		</div>
+	</div>
+</div>
+<%- include('bottom') %>
diff --git a/nodejs/views/login.ejs b/nodejs/views/login.ejs
index 858427a..85b9c97 100755
--- a/nodejs/views/login.ejs
+++ b/nodejs/views/login.ejs
@@ -1,15 +1,22 @@
 <%- include('top') %>
 <script type="text/javascript">
 
-	app.auth.isLoggedIn(function(error, isLoggedIn){
-		if(isLoggedIn){
-			app.auth.logInRedirect();
-		}
-	})
+	// If we arrived from the OIDC callback with a token in the URL fragment,
+	// store it and forward on before doing anything else.
+	if(!app.auth.consumeTokenFragment()){
+		app.auth.isLoggedIn(function(error, isLoggedIn){
+			if(isLoggedIn){
+				app.auth.logInRedirect();
+			}else{
+				// Reveal the login card once we know the user is not logged in.
+				document.getElementById('login-card-row').style.display = '';
+			}
+		})
+	}
 
 </script>
 
-<div class="row" style="display: none;">
+<div id="login-card-row" class="row" style="display: none;">
 	<div class="col-md-4">
 		<div class="shadow-lg card">
 
@@ -74,6 +81,13 @@
 					<hr />
 					<button type="submit" class="btn btn-outline-dark"><i class="fa-solid fa-right-to-bracket"></i> Log in</button>
 				</form>
+
+				<hr />
+				<div class="d-grid">
+					<a href="/api/auth/oidc/start" class="btn btn-outline-primary">
+						<i class="fa-solid fa-id-badge"></i> Log in with SSO
+					</a>
+				</div>
 			</div>
 		</div>
 	</div>
diff --git a/nodejs/views/top.ejs b/nodejs/views/top.ejs
index f40a3e7..d52ee61 100755
--- a/nodejs/views/top.ejs
+++ b/nodejs/views/top.ejs
@@ -51,11 +51,16 @@
 							DNS
 						</a>
 					</li>
-					<li class="nav-item">
+					<li class="nav-item nav-admin" style="display: none;">
 						<a class="nav-link" href="/users"><i class="fa-solid fa-users"></i>
 							Users
 						</a>
 					</li>
+					<li class="nav-item nav-admin" style="display: none;">
+						<a class="nav-link" href="/grants"><i class="fa-solid fa-user-shield"></i>
+							Grants
+						</a>
+					</li>
 					<li class="nav-item">
 						<a class="nav-link" href="https://github.com/theta42/proxy" target="_blank">
 							<i class="fa-brands fa-github"></i>
@@ -87,10 +92,13 @@
 					}
 				})
 
-				// Set the correct login/logout button
+				// Set the correct login/logout button, and reveal admin-only nav
+				// items for global admins.
 				app.auth.isLoggedIn(function(error, data){
 					if(data) $('#cl-logout-button').show();
 					else $('#cl-login-button').show();
+
+					if(data && data.isAdmin) $('.nav-admin').css('display', '');
 				});
 
 			});
diff --git a/ops/nginx_conf/targetinfo.lua b/ops/nginx_conf/targetinfo.lua
index 67c2702..c1dd15e 100644
--- a/ops/nginx_conf/targetinfo.lua
+++ b/ops/nginx_conf/targetinfo.lua
@@ -13,7 +13,14 @@ print("In targetInfo module")
 
 -- Main function of the module
 function M.get(ngx, domain, targetInfo)
-    if targetInfo then
+    -- Reuse a previously-resolved target ONLY when it was resolved for this
+    -- exact host. HTTP/2 connection coalescing lets a browser serve several
+    -- hostnames that share one wildcard cert (e.g. *.718it.biz) over a single
+    -- connection; the SSL phase (request_domain) resolves and caches the
+    -- connection's first host in ngx.ctx.targetInfo. Without the domain check
+    -- below, every coalesced request on that connection would be handed the
+    -- first host's target -- e.g. hassio.718it.biz served from metrics.718it.biz.
+    if targetInfo and ngx.ctx.targetInfo_domain == domain then
         return targetInfo
     end
 
@@ -68,6 +75,10 @@ function M.get(ngx, domain, targetInfo)
     end
 
     ngx.ctx.targetInfo = res
+    -- Remember which host this target was resolved for, so the reuse guard at
+    -- the top can tell a genuine cache hit from a coalesced request for a
+    -- different host on the same connection.
+    ngx.ctx.targetInfo_domain = domain
     ngx.ctx.toAllow = true
 
     return res