From 31f7a040c289e7fd389a0083803f2998bf62b660 Mon Sep 17 00:00:00 2001
From: Filip Skokan <panva.ip@gmail.com>
Date: Thu, 7 Nov 2019 17:43:33 +0100
Subject: [PATCH] fix: use sha512 for Ed25519 and shake256 for Ed448 ID Token
 _hash claims

---
 lib/client.js | 48 +++++++++++++++++++++++++-----------------------
 package.json  |  2 +-
 2 files changed, 26 insertions(+), 24 deletions(-)

diff --git a/lib/client.js b/lib/client.js
index 06c28355..3b652ec9 100644
--- a/lib/client.js
+++ b/lib/client.js
@@ -791,6 +791,18 @@ module.exports = (issuer, aadIssValidation = false) => class Client extends Base
       });
     }
 
+    let key;
+
+    if (header.alg.startsWith('HS')) {
+      key = await this.joseSecret();
+    } else if (header.alg !== 'none') {
+      key = await this.issuer.key(header);
+    }
+
+    if (header.alg !== 'none' && !key) {
+      throw new RPError('could not find a key to validate the signature with');
+    }
+
     if (returnedBy === 'authorization') {
       if (!payload.at_hash && tokenSet.access_token) {
         throw new RPError({
@@ -809,30 +821,28 @@ module.exports = (issuer, aadIssValidation = false) => class Client extends Base
         if (!state) {
           throw new TypeError('cannot verify s_hash, "checks.state" property not provided');
         }
-        if (!tokenHash(payload.s_hash, state, header.alg)) {
-          throw new RPError({
-            printf: ['s_hash mismatch, expected %s, got: %s', tokenHash.generate(state, header.alg), payload.s_hash],
-            jwt: idToken,
-          });
+
+        try {
+          tokenHash.validate({ claim: 's_hash', source: 'state' }, payload.s_hash, state, header.alg, key && key.crv);
+        } catch (err) {
+          throw new RPError({ message: err.message, jwt: idToken });
         }
       }
     }
 
     if (tokenSet.access_token && payload.at_hash !== undefined) {
-      if (!tokenHash(payload.at_hash, tokenSet.access_token, header.alg)) {
-        throw new RPError({
-          printf: ['at_hash mismatch, expected %s, got: %s', tokenHash.generate(tokenSet.access_token, header.alg), payload.at_hash],
-          jwt: idToken,
-        });
+      try {
+        tokenHash.validate({ claim: 'at_hash', source: 'access_token' }, payload.at_hash, tokenSet.access_token, header.alg, key && key.crv);
+      } catch (err) {
+        throw new RPError({ message: err.message, jwt: idToken });
       }
     }
 
     if (tokenSet.code && payload.c_hash !== undefined) {
-      if (!tokenHash(payload.c_hash, tokenSet.code, header.alg)) {
-        throw new RPError({
-          printf: ['c_hash mismatch, expected %s, got: %s', tokenHash.generate(tokenSet.code, header.alg), payload.c_hash],
-          jwt: idToken,
-        });
+      try {
+        tokenHash.validate({ claim: 'c_hash', source: 'code' }, payload.c_hash, tokenSet.code, header.alg, key && key.crv);
+      } catch (err) {
+        throw new RPError({ message: err.message, jwt: idToken });
       }
     }
 
@@ -840,14 +850,6 @@ module.exports = (issuer, aadIssValidation = false) => class Client extends Base
       return tokenSet;
     }
 
-    let key;
-
-    if (header.alg.startsWith('HS')) {
-      key = await this.joseSecret();
-    } else {
-      key = await this.issuer.key(header);
-    }
-
     try {
       jose.JWS.verify(idToken, key);
     } catch (err) {
diff --git a/package.json b/package.json
index 48230d26..5a7bdbad 100644
--- a/package.json
+++ b/package.json
@@ -46,7 +46,7 @@
     "lru-cache": "^5.1.1",
     "make-error": "^1.3.5",
     "object-hash": "^2.0.0",
-    "oidc-token-hash": "^3.0.2",
+    "oidc-token-hash": "^4.0.0",
     "p-any": "^2.1.0"
   },
   "devDependencies": {