From 3afd537a3c2319f68280804004e9bf2e798a43f7 Mon Sep 17 00:00:00 2001 From: David Benjamin Date: Tue, 11 Sep 2018 13:49:28 -0700 Subject: Reduce inputs before the RSAZ code. The RSAZ code requires the input be fully-reduced. To be consistent with the other codepaths, move the BN_nnmod logic before the RSAZ check. This fixes an oft-reported fuzzer bug. https://github.com/google/oss-fuzz/issues/1761 Reviewed-by: Paul Dale (Merged from https://github.com/openssl/openssl/pull/7187) --- test/bntest.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) (limited to 'test/bntest.c') diff --git a/test/bntest.c b/test/bntest.c index e760c64f7f..d042a3e2ba 100644 --- a/test/bntest.c +++ b/test/bntest.c @@ -519,6 +519,31 @@ static int test_modexp_mont5(void) if (!TEST_BN_eq(c, d)) goto err; + /* + * rsaz_1024_mul_avx2 expects fully-reduced inputs. + * BN_mod_exp_mont_consttime should reduce the input first. + */ + BN_hex2bn(&a, + "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF" + "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF" + "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF" + "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF2020202020DF"); + BN_hex2bn(&b, + "1FA53F26F8811C58BE0357897AA5E165693230BC9DF5F01DFA6A2D59229EC69D" + "9DE6A89C36E3B6957B22D6FAAD5A3C73AE587B710DBE92E83D3A9A3339A085CB" + "B58F508CA4F837924BB52CC1698B7FDC2FD74362456A595A5B58E38E38E38E38" + "E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E"); + BN_hex2bn(&n, + "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF" + "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF" + "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF" + "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF2020202020DF"); + BN_MONT_CTX_set(mont, n, ctx); + BN_mod_exp_mont_consttime(c, a, b, n, ctx, mont); + BN_zero(d); + if (!TEST_BN_eq(c, d)) + goto err; + /* Zero input */ BN_bntest_rand(p, 1024, 0, 0); BN_zero(a); -- cgit v1.2.3