1 files changed, 66 insertions, 0 deletions
diff --git a/src/libs/3rdparty/botan/src/lib/pubkey/blinding.cpp b/src/libs/3rdparty/botan/src/lib/pubkey/blinding.cpp
new file mode 100644
index 0000000000..ecd420780c
--- /dev/null
+++ b/src/libs/3rdparty/botan/src/lib/pubkey/blinding.cpp
@@ -0,0 +1,66 @@
+/*
+* Blinding for public key operations
+* (C) 1999-2010,2015 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/blinding.h>
+
+namespace Botan {
+
+Blinder::Blinder(const BigInt& modulus,
+                 RandomNumberGenerator& rng,
+                 std::function<BigInt (const BigInt&)> fwd,
+                 std::function<BigInt (const BigInt&)> inv) :
+      m_reducer(modulus),
+      m_rng(rng),
+      m_fwd_fn(fwd),
+      m_inv_fn(inv),
+      m_modulus_bits(modulus.bits()),
+      m_e{},
+      m_d{},
+      m_counter{}
+   {
+   const BigInt k = blinding_nonce();
+   m_e = m_fwd_fn(k);
+   m_d = m_inv_fn(k);
+   }
+
+BigInt Blinder::blinding_nonce() const
+   {
+   return BigInt(m_rng, m_modulus_bits - 1);
+   }
+
+BigInt Blinder::blind(const BigInt& i) const
+   {
+   if(!m_reducer.initialized())
+      throw Exception("Blinder not initialized, cannot blind");
+
+   ++m_counter;
+
+   if((BOTAN_BLINDING_REINIT_INTERVAL > 0) && (m_counter > BOTAN_BLINDING_REINIT_INTERVAL))
+      {
+      const BigInt k = blinding_nonce();
+      m_e = m_fwd_fn(k);
+      m_d = m_inv_fn(k);
+      m_counter = 0;
+      }
+   else
+      {
+      m_e = m_reducer.square(m_e);
+      m_d = m_reducer.square(m_d);
+      }
+
+   return m_reducer.multiply(i, m_e);
+   }
+
+BigInt Blinder::unblind(const BigInt& i) const
+   {
+   if(!m_reducer.initialized())
+      throw Exception("Blinder not initialized, cannot unblind");
+
+   return m_reducer.multiply(i, m_d);
+   }
+
+}