Merge pull request #6777 from tom-cosgrove-arm/issue-6292-mod_inv

Bignum: Implement high level fixed width modular inversion
This commit is contained in:
Gilles Peskine 2022-12-17 13:26:02 +01:00 committed by GitHub
commit e162b4725c
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GPG key ID: 4AEE18F83AFDEB23
15 changed files with 593 additions and 46 deletions

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@ -824,6 +824,40 @@ mbedtls_mpi_uint mbedtls_mpi_core_sub_int( mbedtls_mpi_uint *X,
return( c );
}
mbedtls_mpi_uint mbedtls_mpi_core_check_zero_ct( const mbedtls_mpi_uint *A,
size_t limbs )
{
mbedtls_mpi_uint bits = 0;
for( size_t i = 0; i < limbs; i++ )
bits |= A[i];
return( bits );
}
void mbedtls_mpi_core_to_mont_rep( mbedtls_mpi_uint *X,
const mbedtls_mpi_uint *A,
const mbedtls_mpi_uint *N,
size_t AN_limbs,
mbedtls_mpi_uint mm,
const mbedtls_mpi_uint *rr,
mbedtls_mpi_uint *T )
{
mbedtls_mpi_core_montmul( X, A, rr, AN_limbs, N, AN_limbs, mm, T );
}
void mbedtls_mpi_core_from_mont_rep( mbedtls_mpi_uint *X,
const mbedtls_mpi_uint *A,
const mbedtls_mpi_uint *N,
size_t AN_limbs,
mbedtls_mpi_uint mm,
mbedtls_mpi_uint *T )
{
const mbedtls_mpi_uint Rinv = 1; /* 1/R in Mont. rep => 1 */
mbedtls_mpi_core_montmul( X, A, &Rinv, 1, N, AN_limbs, mm, T );
}
/* END MERGE SLOT 3 */
/* BEGIN MERGE SLOT 4 */

View file

@ -555,6 +555,10 @@ int mbedtls_mpi_core_random( mbedtls_mpi_uint *X,
* \brief Returns the number of limbs of working memory required for
* a call to `mbedtls_mpi_core_exp_mod()`.
*
* \note This will always be at least
* `mbedtls_mpi_core_montmul_working_limbs(AN_limbs)`,
* i.e. sufficient for a call to `mbedtls_mpi_core_montmul()`.
*
* \param AN_limbs The number of limbs in the input `A` and the modulus `N`
* (they must be the same size) that will be given to
* `mbedtls_mpi_core_exp_mod()`.
@ -625,6 +629,111 @@ mbedtls_mpi_uint mbedtls_mpi_core_sub_int( mbedtls_mpi_uint *X,
mbedtls_mpi_uint b,
size_t limbs );
/**
* \brief Determine if a given MPI has the value \c 0 in constant time with
* respect to the value (but not with respect to the number of limbs).
*
* \param[in] A The MPI to test.
* \param limbs Number of limbs in \p A.
*
* \return 0 if `A == 0`
* non-0 (may be any value) if `A != 0`.
*/
mbedtls_mpi_uint mbedtls_mpi_core_check_zero_ct( const mbedtls_mpi_uint *A,
size_t limbs );
/**
* \brief Returns the number of limbs of working memory required for
* a call to `mbedtls_mpi_core_montmul()`.
*
* \param AN_limbs The number of limbs in the input `A` and the modulus `N`
* (they must be the same size) that will be given to
* `mbedtls_mpi_core_montmul()` or one of the other functions
* that specifies this as the amount of working memory needed.
*
* \return The number of limbs of working memory required by
* `mbedtls_mpi_core_montmul()` (or other similar function).
*/
static inline size_t mbedtls_mpi_core_montmul_working_limbs( size_t AN_limbs )
{
return( 2 * AN_limbs + 1 );
}
/** Convert an MPI into Montgomery form.
*
* \p X may be aliased to \p A, but may not otherwise overlap it.
*
* \p X may not alias \p N (it is in canonical form, so must be stricly less
* than \p N). Nor may it alias or overlap \p rr (this is unlikely to be
* required in practice.)
*
* This function is a thin wrapper around `mbedtls_mpi_core_montmul()` that is
* an alternative to calling `mbedtls_mpi_mod_raw_to_mont_rep()` when we
* don't want to allocate memory.
*
* \param[out] X The result of the conversion.
* Must have the same number of limbs as \p A.
* \param[in] A The MPI to convert into Montgomery form.
* Must have the same number of limbs as the modulus.
* \param[in] N The address of the modulus, which gives the size of
* the base `R` = 2^(biL*N->limbs).
* \param[in] AN_limbs The number of limbs in \p X, \p A, \p N and \p rr.
* \param mm The Montgomery constant for \p N: -N^-1 mod 2^biL.
* This can be determined by calling
* `mbedtls_mpi_core_montmul_init()`.
* \param[in] rr The residue for `2^{2*n*biL} mod N`.
* \param[in,out] T Temporary storage of size at least
* `mbedtls_mpi_core_montmul_working_limbs(AN_limbs)`
* limbs.
* Its initial content is unused and
* its final content is indeterminate.
* It must not alias or otherwise overlap any of the
* other parameters.
*/
void mbedtls_mpi_core_to_mont_rep( mbedtls_mpi_uint *X,
const mbedtls_mpi_uint *A,
const mbedtls_mpi_uint *N,
size_t AN_limbs,
mbedtls_mpi_uint mm,
const mbedtls_mpi_uint *rr,
mbedtls_mpi_uint *T );
/** Convert an MPI from Montgomery form.
*
* \p X may be aliased to \p A, but may not otherwise overlap it.
*
* \p X may not alias \p N (it is in canonical form, so must be stricly less
* than \p N).
*
* This function is a thin wrapper around `mbedtls_mpi_core_montmul()` that is
* an alternative to calling `mbedtls_mpi_mod_raw_from_mont_rep()` when we
* don't want to allocate memory.
*
* \param[out] X The result of the conversion.
* Must have the same number of limbs as \p A.
* \param[in] A The MPI to convert from Montgomery form.
* Must have the same number of limbs as the modulus.
* \param[in] N The address of the modulus, which gives the size of
* the base `R` = 2^(biL*N->limbs).
* \param[in] AN_limbs The number of limbs in \p X, \p A and \p N.
* \param mm The Montgomery constant for \p N: -N^-1 mod 2^biL.
* This can be determined by calling
* `mbedtls_mpi_core_montmul_init()`.
* \param[in,out] T Temporary storage of size at least
* `mbedtls_mpi_core_montmul_working_limbs(AN_limbs)`
* limbs.
* Its initial content is unused and
* its final content is indeterminate.
* It must not alias or otherwise overlap any of the
* other parameters.
*/
void mbedtls_mpi_core_from_mont_rep( mbedtls_mpi_uint *X,
const mbedtls_mpi_uint *A,
const mbedtls_mpi_uint *N,
size_t AN_limbs,
mbedtls_mpi_uint mm,
mbedtls_mpi_uint *T );
/* END MERGE SLOT 3 */
/* BEGIN MERGE SLOT 4 */

View file

@ -79,7 +79,7 @@ void mbedtls_mpi_mod_modulus_free( mbedtls_mpi_mod_modulus *m )
if (m->rep.mont.rr != NULL)
{
mbedtls_platform_zeroize( (mbedtls_mpi_uint *) m->rep.mont.rr,
m->limbs );
m->limbs * sizeof(mbedtls_mpi_uint) );
mbedtls_free( (mbedtls_mpi_uint *)m->rep.mont.rr );
m->rep.mont.rr = NULL;
}
@ -191,6 +191,95 @@ int mbedtls_mpi_mod_sub( mbedtls_mpi_mod_residue *X,
return( 0 );
}
static int mbedtls_mpi_mod_inv_mont( mbedtls_mpi_mod_residue *X,
const mbedtls_mpi_mod_residue *A,
const mbedtls_mpi_mod_modulus *N,
mbedtls_mpi_uint *working_memory )
{
/* Input already in Montgomery form, so there's little to do */
mbedtls_mpi_mod_raw_inv_prime( X->p, A->p,
N->p, N->limbs,
N->rep.mont.rr,
working_memory );
return( 0 );
}
static int mbedtls_mpi_mod_inv_non_mont( mbedtls_mpi_mod_residue *X,
const mbedtls_mpi_mod_residue *A,
const mbedtls_mpi_mod_modulus *N,
mbedtls_mpi_uint *working_memory )
{
/* Need to convert input into Montgomery form */
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
mbedtls_mpi_mod_modulus Nmont;
mbedtls_mpi_mod_modulus_init( &Nmont );
MBEDTLS_MPI_CHK( mbedtls_mpi_mod_modulus_setup( &Nmont, N->p, N->limbs,
MBEDTLS_MPI_MOD_REP_MONTGOMERY ) );
/* We'll use X->p to hold the Montgomery form of the input A->p */
mbedtls_mpi_core_to_mont_rep( X->p, A->p, Nmont.p, Nmont.limbs,
Nmont.rep.mont.mm, Nmont.rep.mont.rr,
working_memory );
mbedtls_mpi_mod_raw_inv_prime( X->p, X->p,
Nmont.p, Nmont.limbs,
Nmont.rep.mont.rr,
working_memory );
/* And convert back from Montgomery form */
mbedtls_mpi_core_from_mont_rep( X->p, X->p, Nmont.p, Nmont.limbs,
Nmont.rep.mont.mm, working_memory );
cleanup:
mbedtls_mpi_mod_modulus_free( &Nmont );
return( ret );
}
int mbedtls_mpi_mod_inv( mbedtls_mpi_mod_residue *X,
const mbedtls_mpi_mod_residue *A,
const mbedtls_mpi_mod_modulus *N )
{
if( X->limbs != N->limbs || A->limbs != N->limbs )
return( MBEDTLS_ERR_MPI_BAD_INPUT_DATA );
/* Zero has the same value regardless of Montgomery form or not */
if( mbedtls_mpi_core_check_zero_ct( A->p, A->limbs ) == 0 )
return( MBEDTLS_ERR_MPI_BAD_INPUT_DATA );
size_t working_limbs =
mbedtls_mpi_mod_raw_inv_prime_working_limbs( N->limbs );
mbedtls_mpi_uint *working_memory = mbedtls_calloc( working_limbs,
sizeof(mbedtls_mpi_uint) );
if( working_memory == NULL )
return( MBEDTLS_ERR_MPI_ALLOC_FAILED );
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
switch( N->int_rep )
{
case MBEDTLS_MPI_MOD_REP_MONTGOMERY:
ret = mbedtls_mpi_mod_inv_mont( X, A, N, working_memory );
break;
case MBEDTLS_MPI_MOD_REP_OPT_RED:
ret = mbedtls_mpi_mod_inv_non_mont( X, A, N, working_memory );
break;
default:
ret = MBEDTLS_ERR_MPI_BAD_INPUT_DATA;
break;
}
mbedtls_platform_zeroize( working_memory,
working_limbs * sizeof(mbedtls_mpi_uint) );
mbedtls_free( working_memory );
return ret;
}
/* END MERGE SLOT 3 */
/* BEGIN MERGE SLOT 4 */

View file

@ -249,6 +249,35 @@ int mbedtls_mpi_mod_sub( mbedtls_mpi_mod_residue *X,
const mbedtls_mpi_mod_residue *A,
const mbedtls_mpi_mod_residue *B,
const mbedtls_mpi_mod_modulus *N );
/**
* \brief Perform modular inversion of an MPI with respect to a modulus \p N.
*
* \p A and \p X must be associated with the modulus \p N and will therefore
* have the same number of limbs as \p N.
*
* \p X may be aliased to \p A.
*
* \warning Currently only supports prime moduli, but does not check for them.
*
* \param[out] X The modular inverse of \p A with respect to \p N.
* \param[in] A The number to calculate the modular inverse of.
* Must not be 0.
* \param[in] N The modulus to use.
*
* \return \c 0 if successful.
* \return #MBEDTLS_ERR_MPI_BAD_INPUT_DATA if \p A and \p N do not
* have the same number of limbs.
* \return #MBEDTLS_ERR_MPI_BAD_INPUT_DATA if \p A is zero.
* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED if couldn't allocate enough
* memory (needed for conversion to and from Mongtomery form
* when not in Montgomery form already, and for temporary use
* by the inversion calculation itself).
*/
int mbedtls_mpi_mod_inv( mbedtls_mpi_mod_residue *X,
const mbedtls_mpi_mod_residue *A,
const mbedtls_mpi_mod_modulus *N );
/* END MERGE SLOT 3 */
/* BEGIN MERGE SLOT 4 */

View file

@ -193,13 +193,13 @@ int mbedtls_mpi_mod_raw_to_mont_rep( mbedtls_mpi_uint *X,
const mbedtls_mpi_mod_modulus *m )
{
mbedtls_mpi_uint *T;
const size_t t_limbs = m->limbs * 2 + 1;
const size_t t_limbs = mbedtls_mpi_core_montmul_working_limbs( m->limbs );
if( ( T = (mbedtls_mpi_uint *) mbedtls_calloc( t_limbs, ciL ) ) == NULL )
return( MBEDTLS_ERR_MPI_ALLOC_FAILED );
mbedtls_mpi_core_montmul( X, X, m->rep.mont.rr, m->limbs, m->p, m->limbs,
m->rep.mont.mm, T );
mbedtls_mpi_core_to_mont_rep( X, X, m->p, m->limbs,
m->rep.mont.mm, m->rep.mont.rr, T );
mbedtls_platform_zeroize( T, t_limbs * ciL );
mbedtls_free( T );
@ -209,15 +209,13 @@ int mbedtls_mpi_mod_raw_to_mont_rep( mbedtls_mpi_uint *X,
int mbedtls_mpi_mod_raw_from_mont_rep( mbedtls_mpi_uint *X,
const mbedtls_mpi_mod_modulus *m )
{
const mbedtls_mpi_uint one = 1;
const size_t t_limbs = m->limbs * 2 + 1;
const size_t t_limbs = mbedtls_mpi_core_montmul_working_limbs( m->limbs );
mbedtls_mpi_uint *T;
if( ( T = (mbedtls_mpi_uint *) mbedtls_calloc( t_limbs, ciL ) ) == NULL )
return( MBEDTLS_ERR_MPI_ALLOC_FAILED );
mbedtls_mpi_core_montmul( X, X, &one, 1, m->p, m->limbs,
m->rep.mont.mm, T );
mbedtls_mpi_core_from_mont_rep( X, X, m->p, m->limbs, m->rep.mont.mm, T );
mbedtls_platform_zeroize( T, t_limbs * ciL );
mbedtls_free( T );

View file

@ -258,6 +258,10 @@ void mbedtls_mpi_mod_raw_mul( mbedtls_mpi_uint *X,
* \brief Returns the number of limbs of working memory required for
* a call to `mbedtls_mpi_mod_raw_inv_prime()`.
*
* \note This will always be at least
* `mbedtls_mpi_core_montmul_working_limbs(AN_limbs)`,
* i.e. sufficient for a call to `mbedtls_mpi_core_montmul()`.
*
* \param AN_limbs The number of limbs in the input `A` and the modulus `N`
* (they must be the same size) that will be given to
* `mbedtls_mpi_mod_raw_inv_prime()`.

View file

@ -39,6 +39,11 @@ def invmod(a: int, n: int) -> int:
return b
raise ValueError("Not invertible")
def invmod_positive(a: int, n: int) -> int:
"""Return a non-negative inverse of a to modulo n."""
inv = invmod(a, n)
return inv if inv >= 0 else inv + n
def hex_to_int(val: str) -> int:
"""Implement the syntax accepted by mbedtls_test_read_mpi().
@ -244,6 +249,8 @@ class ModOperationCommon(OperationCommon):
#pylint: disable=abstract-method
"""Target for bignum mod_raw test case generation."""
moduli = MODULI_DEFAULT # type: List[str]
montgomery_form_a = False
disallow_zero_a = False
def __init__(self, val_n: str, val_a: str, val_b: str = "0",
bits_in_limb: int = 64) -> None:
@ -263,6 +270,14 @@ class ModOperationCommon(OperationCommon):
def boundary(self) -> int:
return self.int_n
@property
def arg_a(self) -> str:
if self.montgomery_form_a:
value_a = self.to_montgomery(self.int_a)
else:
value_a = self.int_a
return self.format_arg('{:x}'.format(value_a))
@property
def arg_n(self) -> str:
return self.format_arg(self.val_n)
@ -287,6 +302,8 @@ class ModOperationCommon(OperationCommon):
def is_valid(self) -> bool:
if self.int_a >= self.int_n:
return False
if self.disallow_zero_a and self.int_a == 0:
return False
if self.arity == 2 and self.int_b >= self.int_n:
return False
return True

View file

@ -757,15 +757,7 @@ class BignumCoreExpMod(BignumCoreTarget, bignum_common.ModOperationCommon):
test_function = "mpi_core_exp_mod"
test_name = "Core modular exponentiation (Mongtomery form only)"
input_style = "fixed"
def arguments(self) -> List[str]:
# Input 'a' has to be given in Montgomery form
mont_a = self.to_montgomery(self.int_a)
arg_mont_a = self.format_arg('{:x}'.format(mont_a))
return [bignum_common.quote_str(n) for n in [self.arg_n,
arg_mont_a,
self.arg_b]
] + self.result()
montgomery_form_a = True
def result(self) -> List[str]:
# Result has to be given in Montgomery form too
@ -818,6 +810,20 @@ class BignumCoreSubInt(BignumCoreTarget, bignum_common.OperationCommon):
str(-borrow)
]
class BignumCoreZeroCheckCT(BignumCoreTarget, bignum_common.OperationCommon):
"""Test cases for bignum core zero check (constant flow)."""
count = 0
symbol = "== 0"
test_function = "mpi_core_check_zero_ct"
test_name = "mpi_core_check_zero_ct"
input_style = "variable"
arity = 1
suffix = True
def result(self) -> List[str]:
result = 1 if self.int_a == 0 else 0
return [str(result)]
# END MERGE SLOT 3
# BEGIN MERGE SLOT 4

View file

@ -121,6 +121,9 @@ MODULI_DEFAULT = [
ONLY_PRIME_MODULI = [
"53", # safe prime
"8ac72304057392b5", # 9999999997777777333 (longer, not safe, prime)
# The next prime has a different R in Montgomery form depending on
# whether 32- or 64-bit MPIs are used.
"152d02c7e14af67fe0bf", # 99999999999999999991999
SAFE_PRIME_192_BIT_SEED_1, # safe prime
SAFE_PRIME_1024_BIT_SEED_3, # safe prime
]

View file

@ -18,6 +18,7 @@ from typing import Dict, List
from . import test_data_generation
from . import bignum_common
from .bignum_data import ONLY_PRIME_MODULI
class BignumModTarget(test_data_generation.BaseTarget):
#pylint: disable=abstract-method, too-few-public-methods
@ -48,6 +49,42 @@ class BignumModSub(bignum_common.ModOperationCommon, BignumModTarget):
# generated cases
return [self.format_result(result), "0"]
class BignumModInvNonMont(bignum_common.ModOperationCommon, BignumModTarget):
"""Test cases for bignum mpi_mod_inv() - not in Montgomery form."""
moduli = ONLY_PRIME_MODULI # for now only prime moduli supported
symbol = "^ -1"
test_function = "mpi_mod_inv_non_mont"
test_name = "mbedtls_mpi_mod_inv non-Mont. form"
input_style = "fixed"
arity = 1
suffix = True
disallow_zero_a = True
def result(self) -> List[str]:
result = bignum_common.invmod_positive(self.int_a, self.int_n)
# To make negative tests easier, append 0 for success to the
# generated cases
return [self.format_result(result), "0"]
class BignumModInvMont(bignum_common.ModOperationCommon, BignumModTarget):
"""Test cases for bignum mpi_mod_inv() - Montgomery form."""
moduli = ONLY_PRIME_MODULI # for now only prime moduli supported
symbol = "^ -1"
test_function = "mpi_mod_inv_mont"
test_name = "mbedtls_mpi_mod_inv Mont. form"
input_style = "arch_split" # Mont. form requires arch_split
arity = 1
suffix = True
disallow_zero_a = True
montgomery_form_a = True
def result(self) -> List[str]:
result = bignum_common.invmod_positive(self.int_a, self.int_n)
mont_result = self.to_montgomery(result)
# To make negative tests easier, append 0 for success to the
# generated cases
return [self.format_result(mont_result), "0"]
# END MERGE SLOT 3
# BEGIN MERGE SLOT 4

View file

@ -80,24 +80,14 @@ class BignumModRawInvPrime(bignum_common.ModOperationCommon,
symbol = "^ -1"
test_function = "mpi_mod_raw_inv_prime"
test_name = "mbedtls_mpi_mod_raw_inv_prime (Montgomery form only)"
input_style = "fixed"
input_style = "arch_split"
arity = 1
suffix = True
@property
def is_valid(self) -> bool:
return self.int_a > 0 and self.int_a < self.int_n
@property
def arg_a(self) -> str:
# Input has to be given in Montgomery form
mont_a = self.to_montgomery(self.int_a)
return self.format_arg('{:x}'.format(mont_a))
montgomery_form_a = True
disallow_zero_a = True
def result(self) -> List[str]:
result = bignum_common.invmod(self.int_a, self.int_n)
if result < 0:
result += self.int_n
result = bignum_common.invmod_positive(self.int_a, self.int_n)
mont_result = self.to_montgomery(result)
return [self.format_result(mont_result)]

View file

@ -848,7 +848,9 @@ void mpi_core_montmul( int limbs_AN4, int limbs_B4,
TEST_EQUAL( 0, mbedtls_mpi_grow( X, limbs_AN ) );
TEST_EQUAL( 0, mbedtls_mpi_grow( &B, limbs_B ) );
TEST_EQUAL( 0, mbedtls_mpi_grow( &T, limbs_AN * 2 + 1 ) );
size_t working_limbs = mbedtls_mpi_core_montmul_working_limbs( limbs_AN );
TEST_EQUAL( working_limbs, limbs_AN * 2 + 1 );
TEST_EQUAL( 0, mbedtls_mpi_grow( &T, working_limbs ) );
/* Calculate the Montgomery constant (this is unit tested separately) */
mbedtls_mpi_uint mm = mbedtls_mpi_core_montmul_init( N.p );
@ -1133,6 +1135,10 @@ void mpi_core_exp_mod( char * input_N, char * input_A,
TEST_LE_U( min_expected_working_limbs, working_limbs );
TEST_LE_U( working_limbs, max_expected_working_limbs );
/* Should also be at least mbedtls_mpi_core_montmul_working_limbs() */
TEST_LE_U( mbedtls_mpi_core_montmul_working_limbs( N_limbs ),
working_limbs );
ASSERT_ALLOC( T, working_limbs );
mbedtls_mpi_core_exp_mod( Y, A, N, N_limbs, E, E_limbs, R2, T );
@ -1212,6 +1218,25 @@ exit:
}
/* END_CASE */
/* BEGIN_CASE */
void mpi_core_check_zero_ct( char *input_X, int expected_is_zero )
{
mbedtls_mpi_uint *X = NULL;
size_t X_limbs;
TEST_EQUAL( 0, mbedtls_test_read_mpi_core( &X, &X_limbs, input_X ) );
TEST_CF_SECRET( X, X_limbs * sizeof( mbedtls_mpi_uint ) );
mbedtls_mpi_uint check = mbedtls_mpi_core_check_zero_ct( X, X_limbs );
int is_zero = (check == 0);
TEST_EQUAL( is_zero, expected_is_zero );
exit:
mbedtls_free( X );
}
/* END_CASE */
/* END MERGE SLOT 3 */
/* BEGIN MERGE SLOT 4 */

View file

@ -208,6 +208,106 @@ exit:
mbedtls_free( X_raw );
}
/* END_CASE */
/* BEGIN_CASE */
void mpi_mod_inv_mont( char * input_N,
char * input_A, char * input_I,
int expected_ret )
{
mbedtls_mpi_mod_residue a = { NULL, 0 }; /* argument */
mbedtls_mpi_mod_residue i = { NULL, 0 }; /* expected inverse wrt N */
mbedtls_mpi_mod_residue x = { NULL, 0 }; /* output */
mbedtls_mpi_uint *X_raw = NULL;
mbedtls_mpi_mod_modulus N;
mbedtls_mpi_mod_modulus_init( &N );
TEST_EQUAL( 0,
test_read_modulus( &N, MBEDTLS_MPI_MOD_REP_MONTGOMERY, input_N ) );
/* test_read_residue() normally checks that inputs have the same number of
* limbs as the modulus. For negative testing we can ask it to skip this
* with a non-zero final parameter. */
TEST_EQUAL( 0, test_read_residue( &a, &N, input_A, expected_ret != 0 ) );
TEST_EQUAL( 0, test_read_residue( &i, &N, input_I, expected_ret != 0 ) );
size_t limbs = N.limbs;
size_t bytes = limbs * sizeof( *X_raw );
ASSERT_ALLOC( X_raw, limbs );
TEST_EQUAL( 0, mbedtls_mpi_mod_residue_setup( &x, &N, X_raw, limbs ) );
TEST_EQUAL( expected_ret, mbedtls_mpi_mod_inv( &x, &a, &N ) );
if( expected_ret == 0 )
{
TEST_COMPARE_MPI_RESIDUES( x, i );
/* a^-1: alias x to a => Correct result */
memcpy( x.p, a.p, bytes );
TEST_EQUAL( 0, mbedtls_mpi_mod_inv( &x, &x, &N ) );
TEST_COMPARE_MPI_RESIDUES( x, i );
}
exit:
mbedtls_free( (void *)N.p ); /* mbedtls_mpi_mod_modulus_free() sets N.p = NULL */
mbedtls_mpi_mod_modulus_free( &N );
mbedtls_free( a.p );
mbedtls_free( i.p );
mbedtls_free( X_raw );
}
/* END_CASE */
/* BEGIN_CASE */
void mpi_mod_inv_non_mont( char * input_N,
char * input_A, char * input_I,
int expected_ret )
{
mbedtls_mpi_mod_residue a = { NULL, 0 }; /* argument */
mbedtls_mpi_mod_residue i = { NULL, 0 }; /* expected inverse wrt N */
mbedtls_mpi_mod_residue x = { NULL, 0 }; /* output */
mbedtls_mpi_uint *X_raw = NULL;
mbedtls_mpi_mod_modulus N;
mbedtls_mpi_mod_modulus_init( &N );
TEST_EQUAL( 0,
test_read_modulus( &N, MBEDTLS_MPI_MOD_REP_OPT_RED, input_N ) );
/* test_read_residue() normally checks that inputs have the same number of
* limbs as the modulus. For negative testing we can ask it to skip this
* with a non-zero final parameter. */
TEST_EQUAL( 0, test_read_residue( &a, &N, input_A, expected_ret != 0 ) );
TEST_EQUAL( 0, test_read_residue( &i, &N, input_I, expected_ret != 0 ) );
size_t limbs = N.limbs;
size_t bytes = limbs * sizeof( *X_raw );
ASSERT_ALLOC( X_raw, limbs );
TEST_EQUAL( 0, mbedtls_mpi_mod_residue_setup( &x, &N, X_raw, limbs ) );
TEST_EQUAL( expected_ret, mbedtls_mpi_mod_inv( &x, &a, &N ) );
if( expected_ret == 0 )
{
TEST_COMPARE_MPI_RESIDUES( x, i );
/* a^-1: alias x to a => Correct result */
memcpy( x.p, a.p, bytes );
TEST_EQUAL( 0, mbedtls_mpi_mod_inv( &x, &x, &N ) );
TEST_COMPARE_MPI_RESIDUES( x, i );
}
exit:
mbedtls_free( (void *)N.p ); /* mbedtls_mpi_mod_modulus_free() sets N.p = NULL */
mbedtls_mpi_mod_modulus_free( &N );
mbedtls_free( a.p );
mbedtls_free( i.p );
mbedtls_free( X_raw );
}
/* END_CASE */
/* END MERGE SLOT 3 */
/* BEGIN MERGE SLOT 4 */

View file

@ -38,6 +38,50 @@ mpi_mod_sub:"014320a022ccb75bdf470ddf25":"a99c71c7":"00033b2e3c9fd0803ce8000f93"
mpi_mod_sub with second input too short
mpi_mod_sub:"014320a022ccb75bdf470ddf25":"000000025a55a46e5da99c71c7":"e8000f93":"00":MBEDTLS_ERR_MPI_BAD_INPUT_DATA
mbedtls_mpi_mod_inv non-Mont. form - base case for negative testing (N, A, A^-1)
mpi_mod_inv_non_mont:"000000000000152d02c7e14af67fe0bf":"00000000000000000000000000000038":"000000000000097418193b6f2e0b5fc3":0
mbedtls_mpi_mod_inv non-Mont. form - A == 0
mpi_mod_inv_non_mont:"000000000000152d02c7e14af67fe0bf":"00000000000000000000000000000000":"00":MBEDTLS_ERR_MPI_BAD_INPUT_DATA
mbedtls_mpi_mod_inv non-Mont. form - A too long
mpi_mod_inv_non_mont:"000000000000152d02c7e14af67fe0bf":"0000000000000000000000000000000000000038":"00":MBEDTLS_ERR_MPI_BAD_INPUT_DATA
mbedtls_mpi_mod_inv non-Mont. form - A too short
mpi_mod_inv_non_mont:"000000000000152d02c7e14af67fe0bf":"0000000000000038":"000000000000097418193b6f2e0b5fc3":MBEDTLS_ERR_MPI_BAD_INPUT_DATA
mbedtls_mpi_mod_inv 32-bit Mont. form - base case for negative testing, A = 1 (N, mont(A), mont(A^-1))
depends_on:MBEDTLS_HAVE_INT32
mpi_mod_inv_mont:"000000000000152d02c7e14af67fe0bf":"0000000000000d71d51539b9c02b7b28":"0000000000000d71d51539b9c02b7b28":0
mbedtls_mpi_mod_inv 32-bit Mont. form - A == 0
depends_on:MBEDTLS_HAVE_INT32
mpi_mod_inv_mont:"000000000000152d02c7e14af67fe0bf":"00000000000000000000000000000000":"00":MBEDTLS_ERR_MPI_BAD_INPUT_DATA
mbedtls_mpi_mod_inv 32-bit Mont. form - A too long
depends_on:MBEDTLS_HAVE_INT32
mpi_mod_inv_mont:"000000000000152d02c7e14af67fe0bf":"000000000000000000000d71d51539b9c02b7b28":"00":MBEDTLS_ERR_MPI_BAD_INPUT_DATA
mbedtls_mpi_mod_inv 32-bit Mont. form - A too short
depends_on:MBEDTLS_HAVE_INT32
mpi_mod_inv_mont:"000000000000152d02c7e14af67fe0bf":"00000d71d51539b9c02b7b28":"0000000000000d71d51539b9c02b7b28":MBEDTLS_ERR_MPI_BAD_INPUT_DATA
mbedtls_mpi_mod_inv 64-bit Mont. form - base case for negative testing, A = 1 (N, mont(A), mont(A^-1))
depends_on:MBEDTLS_HAVE_INT64
mpi_mod_inv_mont:"0000000000000000000000000000152d02c7e14af67fe0bf":"000000000000000000000000000009545642424381c611fb":"000000000000000000000000000009545642424381c611fb":0
mbedtls_mpi_mod_inv 64-bit Mont. form - A == 0
depends_on:MBEDTLS_HAVE_INT64
mpi_mod_inv_mont:"0000000000000000000000000000152d02c7e14af67fe0bf":"000000000000000000000000000000000000000000000000":"000000000000000000000000000009545642424381c611fb":MBEDTLS_ERR_MPI_BAD_INPUT_DATA
mbedtls_mpi_mod_inv 64-bit Mont. form - A too long
depends_on:MBEDTLS_HAVE_INT64
mpi_mod_inv_mont:"0000000000000000000000000000152d02c7e14af67fe0bf":"0000000000000000000000000000000000000000000009545642424381c611fb":"000000000000000000000000000009545642424381c611fb":MBEDTLS_ERR_MPI_BAD_INPUT_DATA
mbedtls_mpi_mod_inv 64-bit Mont. form - A too short
depends_on:MBEDTLS_HAVE_INT64
mpi_mod_inv_mont:"0000000000000000000000000000152d02c7e14af67fe0bf":"00000000000009545642424381c611fb":"000000000000000000000000000009545642424381c611fb":MBEDTLS_ERR_MPI_BAD_INPUT_DATA
# END MERGE SLOT 3
# BEGIN MERGE SLOT 4

View file

@ -489,6 +489,10 @@ void mpi_mod_raw_inv_prime( char * input_N, char * input_A, char * input_X )
TEST_LE_U( min_expected_working_limbs, working_limbs );
TEST_LE_U( working_limbs, max_expected_working_limbs );
/* Should also be at least mbedtls_mpi_core_montmul_working_limbs() */
TEST_LE_U( mbedtls_mpi_core_montmul_working_limbs( N_limbs ),
working_limbs );
ASSERT_ALLOC( T, working_limbs );
mbedtls_mpi_mod_raw_inv_prime( Y, A, N, N_limbs, R2, T );
@ -624,8 +628,10 @@ void mpi_mod_raw_to_mont_rep( char * input_N, char * input_A, char * input_X )
{
mbedtls_mpi_uint *N = NULL;
mbedtls_mpi_uint *A = NULL;
mbedtls_mpi_uint *R = NULL; /* for result of low-level conversion */
mbedtls_mpi_uint *X = NULL;
size_t n_limbs, a_limbs, x_limbs, x_bytes;
mbedtls_mpi_uint *T = NULL;
size_t n_limbs, a_limbs, x_limbs;
mbedtls_mpi_mod_modulus m;
mbedtls_mpi_mod_modulus_init( &m );
@ -634,23 +640,50 @@ void mpi_mod_raw_to_mont_rep( char * input_N, char * input_A, char * input_X )
TEST_EQUAL( 0, mbedtls_test_read_mpi_core( &N, &n_limbs, input_N ) );
TEST_EQUAL( 0, mbedtls_test_read_mpi_core( &A, &a_limbs, input_A ) );
TEST_EQUAL( 0, mbedtls_test_read_mpi_core( &X, &x_limbs, input_X ) );
x_bytes = x_limbs * sizeof(mbedtls_mpi_uint);
/* Test that input does not require more limbs than modulo */
TEST_LE_U(a_limbs, n_limbs);
/* Number to convert must have same number of limbs as modulus */
TEST_EQUAL(a_limbs, n_limbs);
/* Higher-level conversion is in-place, so expected result must have the
* same number of limbs too */
TEST_EQUAL(x_limbs, n_limbs);
size_t limbs = n_limbs;
size_t bytes = limbs * sizeof(mbedtls_mpi_uint);
TEST_EQUAL( 0, mbedtls_mpi_mod_modulus_setup( &m, N, n_limbs,
MBEDTLS_MPI_MOD_REP_MONTGOMERY ) );
/* Convert from cannonical into Montgomery representation */
/* 1. Test low-level function first */
/* It has separate output, and requires temporary working storage */
size_t temp_limbs = mbedtls_mpi_core_montmul_working_limbs( limbs );
ASSERT_ALLOC( T, temp_limbs );
ASSERT_ALLOC( R, limbs );
mbedtls_mpi_core_to_mont_rep( R, A, N, n_limbs,
m.rep.mont.mm, m.rep.mont.rr, T );
/* Test that the low-level function gives the required value */
ASSERT_COMPARE( R, bytes, X, bytes );
/* Test when output is aliased to input */
memcpy( R, A, bytes );
mbedtls_mpi_core_to_mont_rep( R, R, N, n_limbs,
m.rep.mont.mm, m.rep.mont.rr, T );
ASSERT_COMPARE( R, bytes, X, bytes );
/* 2. Test higher-level cannonical to Montgomery conversion */
TEST_EQUAL(0, mbedtls_mpi_mod_raw_to_mont_rep( A, &m ) );
/* The result matches expected value */
ASSERT_COMPARE( A, x_bytes, X, x_bytes );
ASSERT_COMPARE( A, bytes, X, bytes );
exit:
mbedtls_mpi_mod_modulus_free( &m );
mbedtls_free( T );
mbedtls_free( N );
mbedtls_free( A );
mbedtls_free( R );
mbedtls_free( X );
}
/* END_CASE */
@ -660,8 +693,10 @@ void mpi_mod_raw_from_mont_rep( char * input_N, char * input_A, char * input_X )
{
mbedtls_mpi_uint *N = NULL;
mbedtls_mpi_uint *A = NULL;
mbedtls_mpi_uint *R = NULL; /* for result of low-level conversion */
mbedtls_mpi_uint *X = NULL;
size_t n_limbs, a_limbs, x_limbs, x_bytes;
mbedtls_mpi_uint *T = NULL;
size_t n_limbs, a_limbs, x_limbs;
mbedtls_mpi_mod_modulus m;
mbedtls_mpi_mod_modulus_init( &m );
@ -670,23 +705,50 @@ void mpi_mod_raw_from_mont_rep( char * input_N, char * input_A, char * input_X )
TEST_EQUAL( 0, mbedtls_test_read_mpi_core( &N, &n_limbs, input_N ) );
TEST_EQUAL( 0, mbedtls_test_read_mpi_core( &A, &a_limbs, input_A ) );
TEST_EQUAL( 0, mbedtls_test_read_mpi_core( &X, &x_limbs, input_X ) );
x_bytes = x_limbs * sizeof(mbedtls_mpi_uint);
/* Test that input does not require more limbs than modulo */
TEST_LE_U(a_limbs, n_limbs);
/* Number to convert must have same number of limbs as modulus */
TEST_EQUAL(a_limbs, n_limbs);
/* Higher-level conversion is in-place, so expected result must have the
* same number of limbs too */
TEST_EQUAL(x_limbs, n_limbs);
size_t limbs = n_limbs;
size_t bytes = limbs * sizeof(mbedtls_mpi_uint);
TEST_EQUAL( 0, mbedtls_mpi_mod_modulus_setup( &m, N, n_limbs,
MBEDTLS_MPI_MOD_REP_MONTGOMERY ) );
/* Convert from Montgomery into cannonical representation */
/* 1. Test low-level function first */
/* It has separate output, and requires temporary working storage */
size_t temp_limbs = mbedtls_mpi_core_montmul_working_limbs( limbs );
ASSERT_ALLOC( T, temp_limbs );
ASSERT_ALLOC( R, limbs );
mbedtls_mpi_core_from_mont_rep( R, A, N, n_limbs,
m.rep.mont.mm, T );
/* Test that the low-level function gives the required value */
ASSERT_COMPARE( R, bytes, X, bytes );
/* Test when output is aliased to input */
memcpy( R, A, bytes );
mbedtls_mpi_core_from_mont_rep( R, R, N, n_limbs,
m.rep.mont.mm, T );
ASSERT_COMPARE( R, bytes, X, bytes );
/* 2. Test higher-level Montgomery to cannonical conversion */
TEST_EQUAL(0, mbedtls_mpi_mod_raw_from_mont_rep( A, &m ) );
/* The result matches expected value */
ASSERT_COMPARE( A, x_bytes, X, x_bytes );
ASSERT_COMPARE( A, bytes, X, bytes );
exit:
mbedtls_mpi_mod_modulus_free( &m );
mbedtls_free( T );
mbedtls_free( N );
mbedtls_free( A );
mbedtls_free( R );
mbedtls_free( X );
}
/* END_CASE */