lib/mbedtls
1
0
Fork 0
mirror of https://github.com/Mbed-TLS/mbedtls.git synced 2025-12-24 17:41:01 +03:00
Code Activity

Bidnum Mod: fix check in setup

Browse Source 
We want to make sure that the value has at least as many limbs allocated
as the modulus as we need this to be able to do any operations in
constant time.

An invariant of the API is that the residue values are canonical, make
sure that the residue is compared to the entire modulus.

Signed-off-by: Janos Follath <janos.follath@arm.com>
This commit is contained in:
Janos Follath
2022-11-24 16:48:41 +00:00
parent 8b375451c5
commit b62bad442e
2 changed files with 7 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
library/bignum_mod.c
View File

@@ -39,7 +39,7 @@ int mbedtls_mpi_mod_residue_setup( mbedtls_mpi_mod_residue *r,
mbedtls_mpi_uint *p,
size_t p_limbs )
{
if( p_limbs > m->limbs || !mbedtls_mpi_core_lt_ct( p, m->p, p_limbs ) )
if( p_limbs < m->limbs || !mbedtls_mpi_core_lt_ct( p, m->p, m->limbs ) )
return( MBEDTLS_ERR_MPI_BAD_INPUT_DATA );
r->limbs = m->limbs;

12
tests/suites/test_suite_bignum_mod.data
View File

@@ -57,16 +57,16 @@ Test mbedtls_mpi_residue_setup #2 r == m - 1
mpi_residue_setup:"ff":"fe":0
Test mbedtls_mpi_residue_setup #3 m->limbs > r-> limbs && m > r
mpi_residue_setup:"000000000000000000000000000000007dfe5c6beb35a2d6":"fe":0
mpi_residue_setup:"000000000000000000000000000000007dfe5c6beb35a2d6":"fe":MBEDTLS_ERR_MPI_BAD_INPUT_DATA
Test mbedtls_mpi_residue_setup #4 m->limbs > r-> limbs && m > r
mpi_residue_setup:"7ffffffffffffffffffffffffffffffffffffffffffffff1":"fe":0
Test mbedtls_mpi_residue_setup #4 m->limbs = r-> limbs && m > r
mpi_residue_setup:"7ffffffffffffffffffffffffffffffffffffffffffffff1":"0000000000000000000000000000000000000000000000fe":0
Test mbedtls_mpi_residue_setup #5 m->limbs > r-> limbs && m > r
mpi_residue_setup:"7ffffffffffffffffffff000000000000000000000000000":"fe":-4
Test mbedtls_mpi_residue_setup #5 m->limbs < r-> limbs && m > r
mpi_residue_setup:"7ffffffff0000000":"000000000000000fe":0
Test mbedtls_mpi_residue_setup #6 m->limbs < r-> limbs && m > r
mpi_residue_setup:"ff":"000000000000000000000000000000000000000000000001":-4
mpi_residue_setup:"ff":"000000000000000000000000000000000000000000000001":0
Test mbedtls_mpi_residue_setup #7 r == m
mpi_residue_setup:"fe":"fe":-4