cuberite/polarssl
1
0
Fork 0
mirror of https://github.com/cuberite/polarssl.git synced 2025-10-31 03:30:35 -04:00
Code Issues Packages Projects Releases Wiki Activity

mbedtls_mpi_lt_mpi_ct: Improve documentation

Browse Source
This commit is contained in:
Janos Follath 2019-10-28 12:23:18 +00:00
parent 73ba9ec9a6
commit bb5147f165
1 changed files with 4 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
library/bignum.c
View File

@ -1190,6 +1190,7 @@ int mbedtls_mpi_lt_mpi_ct( const mbedtls_mpi *X, const mbedtls_mpi *Y,
unsigned *ret ) unsigned *ret )
{ {
size_t i; size_t i;
/* The value of any of these variables is either 0 or 1 at all times. */
unsigned cond, done, sign_X, sign_Y; unsigned cond, done, sign_X, sign_Y;
MPI_VALIDATE_RET( X != NULL ); MPI_VALIDATE_RET( X != NULL );
@ -1208,14 +1209,14 @@ int mbedtls_mpi_lt_mpi_ct( const mbedtls_mpi *X, const mbedtls_mpi *Y,
/* /*
* If the signs are different, then the positive operand is the bigger. * If the signs are different, then the positive operand is the bigger.
* That is if X is negative (sign bit 1), then X < Y is true and it is false * That is if X is negative (sign_X == 1), then X < Y is true and it is
* if X is positive (sign bit 0). * false if X is positive (sign_X == 0).
*/ */
cond = ( sign_X ^ sign_Y ); cond = ( sign_X ^ sign_Y );
*ret = cond & sign_X; *ret = cond & sign_X;
/* /*
* This is a constant time function, we might have the result, but we still * This is a constant-time function. We might have the result, but we still
* need to go through the loop. Record if we have the result already. * need to go through the loop. Record if we have the result already.
*/ */
done = cond; done = cond;