Add specialized reducers for P-192, P-224, P-256 and P-384

2 files changed, 31 insertions, 39 deletions

diff --git a/src/lib/math/bigint/bigint.cpp b/src/lib/math/bigint/bigint.cpp
index 6acd04f00..b5a8e0dd5 100644
--- a/src/lib/math/bigint/bigint.cpp
+++ b/src/lib/math/bigint/bigint.cpp
@@ -1,6 +1,6 @@
 /*
 * BigInt Base
-* (C) 1999-2011,2012 Jack Lloyd
+* (C) 1999-2011,2012,2014 Jack Lloyd
 *
 * Botan is released under the Simplified BSD License (see license.txt)
 */
@@ -93,15 +93,6 @@ BigInt::BigInt(RandomNumberGenerator& rng, size_t bits)
    }
 
 /*
-* Grow the internal storage
-*/
-void BigInt::grow_to(size_t n)
-   {
-   if(n > size())
-      m_reg.resize(round_up<size_t>(n, 8));
-   }
-
-/*
 * Comparison Function
 */
 s32bit BigInt::cmp(const BigInt& other, bool check_signs) const
@@ -155,8 +146,8 @@ u32bit BigInt::to_u32bit() const
       throw Encoding_Error("BigInt::to_u32bit: Number is too big to convert");
 
    u32bit out = 0;
-   for(u32bit j = 0; j != 4; ++j)
-      out = (out << 8) | byte_at(3-j);
+   for(size_t i = 0; i != 4; ++i)
+      out = (out << 8) | byte_at(3-i);
    return out;
    }
 
@@ -183,30 +174,6 @@ void BigInt::clear_bit(size_t n)
    }
 
 /*
-* Clear all but the lowest n bits
-*/
-void BigInt::mask_bits(size_t n)
-   {
-   if(n == 0) { clear(); return; }
-
-   const size_t top_word = n / MP_WORD_BITS;
-   const word mask = (static_cast<word>(1) << (n % MP_WORD_BITS)) - 1;
-
-   if(top_word < size())
-      clear_mem(&m_reg[top_word+1], size() - (top_word + 1));
-
-   m_reg[top_word] &= mask;
-   }
-
-/*
-* Count how many bytes are being used
-*/
-size_t BigInt::bytes() const
-   {
-   return (bits() + 7) / 8;
-   }
-
-/*
 * Count how many bits are being used
 */
 size_t BigInt::bits() const
diff --git a/src/lib/math/bigint/bigint.h b/src/lib/math/bigint/bigint.h
index 4993f5d0c..269a74259 100644
--- a/src/lib/math/bigint/bigint.h
+++ b/src/lib/math/bigint/bigint.h
@@ -269,7 +269,19 @@ class BOTAN_DLL BigInt
      * Clear all but the lowest n bits
      * @param n amount of bits to keep
      */
-     void mask_bits(size_t n);
+     void mask_bits(size_t n)
+        {
+        if(n == 0) { clear(); return; }
+
+        const size_t top_word = n / BOTAN_MP_WORD_BITS;
+        const word mask = (static_cast<word>(1) << (n % BOTAN_MP_WORD_BITS)) - 1;
+
+        if(top_word < size())
+           {
+           clear_mem(&m_reg[top_word+1], size() - (top_word + 1));
+           m_reg[top_word] &= mask;
+           }
+        }
 
      /**
      * Return bit value at specified position
@@ -315,6 +327,12 @@ class BOTAN_DLL BigInt
      word word_at(size_t n) const
         { return ((n < size()) ? m_reg[n] : 0); }
 
+     void set_word_at(size_t i, word w)
+        {
+        grow_to(i + 1);
+        m_reg[i] = w;
+        }
+
      /**
      * Tests if the sign of the integer is negative
      * @result true, iff the integer has a negative sign
@@ -378,7 +396,7 @@ class BOTAN_DLL BigInt
      * Give byte length of the integer
      * @result byte length of the represented integer value
      */
-     size_t bytes() const;
+     size_t bytes() const { return (bits() + 7) / 8; }
 
      /**
      * Get the bit length of the integer
@@ -398,11 +416,18 @@ class BOTAN_DLL BigInt
      */
      const word* data() const { return &m_reg[0]; }
 
+     secure_vector<word>& get_word_vector() { return m_reg; }
+     const secure_vector<word>& get_word_vector() const { return m_reg; }
+
      /**
      * Increase internal register buffer to at least n words
      * @param n new size of register
      */
-     void grow_to(size_t n);
+     void grow_to(size_t n)
+        {
+        if(n > size())
+           m_reg.resize(n + (8 - n % 8));
+        }
 
      /**
      * Fill BigInt with a random number with size of bitsize