diff options
Diffstat (limited to 'src/powm_mnt.cpp')
| -rw-r--r-- | src/powm_mnt.cpp | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/src/powm_mnt.cpp b/src/powm_mnt.cpp index ad1ac312c..d28bfacfe 100644 --- a/src/powm_mnt.cpp +++ b/src/powm_mnt.cpp @@ -12,6 +12,18 @@ namespace Botan { namespace { /************************************************* +* Montgomery Reduction * +*************************************************/ +void montgomery_reduce(word z[], u32bit z_size, + const word x[], u32bit x_size, word u) + { + bigint_monty_redc(z, z_size, x, x_size, u); + + if(bigint_cmp(z + x_size, x_size + 1, x, x_size) >= 0) + bigint_sub2(z + x_size, x_size + 1, x, x_size); + } + +/************************************************* * Try to choose a good window size * *************************************************/ u32bit choose_window_bits(u32bit exp_bits, u32bit, |