diff options
author | Jack Lloyd <[email protected]> | 2018-12-09 06:45:46 -0500 |
---|---|---|
committer | Jack Lloyd <[email protected]> | 2018-12-09 06:45:46 -0500 |
commit | ef16300624c1f5883f7185eb4316ab7efbed6118 (patch) | |
tree | 6a2ed310b9497288eade7fd1a2301671e5158bcf /src/lib/pubkey/rsa/rsa.cpp | |
parent | e5be97da0c2039fefe4f81ff40c86ae3b88622eb (diff) |
Avoid doing a variable time division during Montgomery setup
Instead require the inputs be reduced already. For RSA-CRT use
Barrett which is const time already. For SRP6 inputs were not reduced,
use the Barrett hook available in DL_Group.
Diffstat (limited to 'src/lib/pubkey/rsa/rsa.cpp')
-rw-r--r-- | src/lib/pubkey/rsa/rsa.cpp | 23 |
1 files changed, 14 insertions, 9 deletions
diff --git a/src/lib/pubkey/rsa/rsa.cpp b/src/lib/pubkey/rsa/rsa.cpp index 9334ff4cd..9f14b9d6a 100644 --- a/src/lib/pubkey/rsa/rsa.cpp +++ b/src/lib/pubkey/rsa/rsa.cpp @@ -238,21 +238,26 @@ class RSA_Private_Operation const BigInt d1_mask(m_blinder.rng(), m_blinding_bits); -#if defined(BOTAN_TARGET_OS_HAS_THREADS) +#if defined(BOTAN_TARGET_OS_HAS_THREADS) && !defined(BOTAN_HAS_VALGRIND) + #define BOTAN_RSA_USE_ASYNC +#endif + + +#if defined(BOTAN_RSA_USE_ASYNC) auto future_j1 = std::async(std::launch::async, [this, &m, &d1_mask, powm_window]() { - const BigInt masked_d1 = m_key.get_d1() + (d1_mask * (m_key.get_p() - 1)); - auto powm_d1_p = monty_precompute(m_monty_p, m, powm_window); - return monty_execute(*powm_d1_p, masked_d1, m_max_d1_bits); - }); -#else +#endif const BigInt masked_d1 = m_key.get_d1() + (d1_mask * (m_key.get_p() - 1)); - auto powm_d1_p = monty_precompute(m_monty_p, m, powm_window); + auto powm_d1_p = monty_precompute(m_monty_p, m_mod_p.reduce(m), powm_window); BigInt j1 = monty_execute(*powm_d1_p, masked_d1, m_max_d1_bits); + +#if defined(BOTAN_RSA_USE_ASYNC) + return j1; + }); #endif const BigInt d2_mask(m_blinder.rng(), m_blinding_bits); const BigInt masked_d2 = m_key.get_d2() + (d2_mask * (m_key.get_q() - 1)); - auto powm_d2_q = monty_precompute(m_monty_q, m, powm_window); + auto powm_d2_q = monty_precompute(m_monty_q, m_mod_q.reduce(m), powm_window); const BigInt j2 = monty_execute(*powm_d2_q, masked_d2, m_max_d2_bits); /* @@ -263,7 +268,7 @@ class RSA_Private_Operation * m = j2 + h*q */ -#if defined(BOTAN_TARGET_OS_HAS_THREADS) +#if defined(BOTAN_RSA_USE_ASYNC) BigInt j1 = future_j1.get(); #endif |