From: Niels Möller <nisse@lysator.liu.se>
Date: Mon, 14 Sep 2015 19:13:37 +0000 (+0200)
Subject: Use rsa_compute_root_tr also in rsa_decrypt_tr.
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=95cef9848bff3f7be6d751008a1a4ebcb821a3e2;p=thirdparty%2Fnettle.git

Use rsa_compute_root_tr also in rsa_decrypt_tr.
---

diff --git a/ChangeLog b/ChangeLog
index 0959eb6f..d199a702 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
 2015-09-14  Niels Möller  <nisse@lysator.liu.se>
 
+	* rsa-decrypt-tr.c (rsa_decrypt_tr): Use rsa_compute_root_tr.
+	Mainly for simplicity and consistency, I'm not aware of any CRT
+	fault attacks on RSA decryption.
+
 	* testsuite/rsa-encrypt-test.c (test_main): Added test with
 	invalid private key.
 
diff --git a/rsa-decrypt-tr.c b/rsa-decrypt-tr.c
index d28badd6..e4fbc5fe 100644
--- a/rsa-decrypt-tr.c
+++ b/rsa-decrypt-tr.c
@@ -48,18 +48,14 @@ rsa_decrypt_tr(const struct rsa_public_key *pub,
 	       size_t *length, uint8_t *message,
 	       const mpz_t gibberish)
 {
-  mpz_t m, ri;
+  mpz_t m;
   int res;
 
   mpz_init_set(m, gibberish);
-  mpz_init (ri);
 
-  _rsa_blind (pub, random_ctx, random, m, ri, m);
-  rsa_compute_root(key, m, m);
-  _rsa_unblind (pub, m, ri, m);
-  mpz_clear (ri);
+  res = (rsa_compute_root_tr (pub, key, random_ctx, random, m, gibberish)
+	 && pkcs1_decrypt (key->size, m, length, message));
 
-  res = pkcs1_decrypt (key->size, m, length, message);
   mpz_clear(m);
   return res;
 }