quickjs-tart

commit ae1e872ae0f09f86fd435dffe287dfbc5d023b54
parent 60aa552c12207f7ef379d685a27fce336e6c26bb
Author: Florian Dold <dold@taler.net>
Date:   Sun,  9 Aug 2026 21:19:54 +0200

tart: clear transient secret material

Diffstat:
M
tart_module.c
 | 
27
++++++++++++++++++++-------

1 file changed, 20 insertions(+), 7 deletions(-)
diff --git a/tart_module.c b/tart_module.c
@@ -597,8 +597,9 @@ static JSValue js_talercrypto_hash_argon2id(JSContext *ctx, JSValue this_val,
         goto exception;
     }
     ret_val = make_js_ta_copy(ctx, hash, hash_len);
- done:
+done:
     if (NULL != hash) {
+        sodium_memzero(hash, hash_len);
         free(hash);
     }
     return ret_val;
@@ -673,22 +674,24 @@ static JSValue js_talercrypto_eddsa_sign(JSContext *ctx, JSValue this_val,
     unsigned char pk[crypto_sign_PUBLICKEYBYTES];
     unsigned char sig[64];
     int res;
+    JSValue ret = JS_EXCEPTION;
 
     data = JS_GetArrayBuffer(ctx, &data_size, argv[0]);
     if (!data) {
-        return JS_EXCEPTION;
+        goto done;
     }
 
     seed = JS_GetArrayBuffer(ctx, &seed_size, argv[1]);
     if (!seed) {
-        return JS_EXCEPTION;
+        goto done;
     }
     if (seed_size != 32) {
-        return JS_ThrowTypeError(ctx, "invalid private key seed size");
+        ret = JS_ThrowTypeError(ctx, "invalid private key seed size");
+        goto done;
     }
 
     if (0 != crypto_sign_seed_keypair(pk, sk, seed)) {
-        return JS_EXCEPTION;
+        goto done;
     }
 
     res = crypto_sign_detached((uint8_t *)sig,
@@ -697,9 +700,12 @@ static JSValue js_talercrypto_eddsa_sign(JSContext *ctx, JSValue this_val,
                                data_size,
                                sk);
     if (res != 0) {
-        return JS_EXCEPTION;
+        goto done;
     }
-    return make_js_ta_copy(ctx, sig, 64);
+    ret = make_js_ta_copy(ctx, sig, 64);
+done:
+    sodium_memzero(sk, sizeof sk);
+    return ret;
 }
 
 /**
@@ -844,6 +850,7 @@ static JSValue js_talercrypto_kdf(JSContext *ctx, JSValue this_val,
     ret_val = make_js_ta_copy(ctx, okm, okm_len);
 done:
     if (NULL != okm) {
+        sodium_memzero(okm, okm_len);
         free(okm);
     }
     return ret_val;
@@ -883,6 +890,8 @@ static JSValue js_talercrypto_kx_ecdh_eddsa(JSContext *ctx, JSValue this_val,
     }
     ret_val = make_js_ta_copy(ctx, key_material, crypto_hash_BYTES);
 done:
+    sodium_memzero(p, sizeof p);
+    sodium_memzero(key_material, sizeof key_material);
     return ret_val;
 exception:
     ret_val = JS_EXCEPTION;
@@ -916,6 +925,10 @@ static JSValue js_talercrypto_kx_eddsa_ecdh(JSContext *ctx, JSValue this_val,
     crypto_hash(key_material, p, crypto_scalarmult_BYTES);
     ret_val = make_js_ta_copy(ctx, key_material, crypto_hash_BYTES);
 done:
+    sodium_memzero(hc, sizeof hc);
+    sodium_memzero(a, sizeof a);
+    sodium_memzero(p, sizeof p);
+    sodium_memzero(key_material, sizeof key_material);
     return ret_val;
 exception:
     ret_val = JS_EXCEPTION;