That rule is common to the whole module and not a likely mistake to
make. Also, the test was not really precise as G, I, T were oversized.
Better remove it than give a false sense of security.
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
This function has specific code to handle carries and it's not clear how
to exercises that code through the modinv function, so well, that's what
unit tests are for.
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
This is consistent with the general rules documented at the top of the
file:
- when computing GCD(A, N), there is no modular arithmetic, so the
output can alias any of the inputs;
- when computing a modular inverse, N is the modulus, so it can't be
aliased by any of the outputs (we'll use it for modular operations
over the entire course of the function's execution).
But since this function has two modes of operations with different
aliasing rules (G can alias N only if I == NULL), I think it should
really be stated explicitly.
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
This is a direct translation of sict_mi2() from
https://github.com/mpg/cryptohack/blob/main/ct-pres.py
which was presented in the book club's special session.
This commit only includes two test cases which is very little. Most of
the test cases will be generated by Python modules that belong to the
framework. However we can't have the framework generate those before we
have the corresponding test function in the consuming branches. So,
extended tests are coming as a 2nd step, after the test function has
been merged.
(The test cases in .misc should stay, as they can be convenient when
working on the test function.)
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
Without this, it's not at all obvious that turning on MBEDTLS_TEST_HOOKS
doesn't change the functional behavior of the code.
Signed-off-by: Janos Follath <janos.follath@arm.com>
The new test hooks allow to check whether there was an unsafe call of an
optionally safe function in the codepath. For the sake of simplicity the
MBEDTLS_MPI_IS_* macros are reused for signalling safe/unsafe codepaths
here too.
Signed-off-by: Janos Follath <janos.follath@arm.com>
The test cases use the following MPI values.
The .data file only includes those (a, b) values where a <= b; the test code
does a * b and b * a.
0 1 80 ff 100 fffe ffff 10000 ffffffff 100000000
20000000000000 7f7f7f7f7f7f7f7f 8000000000000000 ffffffffffffffff
10000000000000000 10000000000000001 1234567890abcdef0
fffffffffffffffffefefefefefefefe 100000000000000000000000000000000
1234567890abcdef01234567890abcdef0
ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
1234567890abcdef01234567890abcdef01234567890abcdef01234567890abcdef0
4df72d07b4b71c8dacb6cffa954f8d88254b6277099308baf003fab73227f34029643b5a263f66e0d3c3fa297ef71755efd53b8fb6cb812c6bbf7bcf179298bd9947c4c8b14324140a2c0f5fad7958a69050a987a6096e9f055fb38edf0c5889eca4a0cfa99b45fbdeee4c696b328ddceae4723945901ec025076b12b
The lines in the .data file were generated by the following script
```
#!/usr/bin/env perl
#
# mpi-test-core-mul.pl - generate MPI tests in Perl for mbedtls_mpi_core_mul()
#
use strict;
use warnings;
use Math::BigInt;
use sort 'stable';
my $echo = 0;
my @mul_mpis = qw(
0 1 80 ff 100 fffe ffff 10000 ffffffff 100000000
20000000000000 7f7f7f7f7f7f7f7f 8000000000000000 ffffffffffffffff
10000000000000000 10000000000000001 1234567890abcdef0 fffffffffffffffffefefefefefefefe
100000000000000000000000000000000 1234567890abcdef01234567890abcdef0
ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
1234567890abcdef01234567890abcdef01234567890abcdef01234567890abcdef0
4df72d07b4b71c8dacb6cffa954f8d88254b6277099308baf003fab73227f34029643b5a263f66e0d3c3fa297ef71755efd53b8fb6cb812c6bbf7bcf179298bd9947c4c8b14324140a2c0f5fad7958a69050a987a6096e9f055fb38edf0c5889eca4a0cfa99b45fbdeee4c696b328ddceae4723945901ec025076b12b
);
generate_tests();
sub generate_tests {
generate_mbedtls_mpi_core_mul();
}
sub generate_mbedtls_mpi_core_mul {
my $sub_name = (caller(0))[3]; # e.g. main::generate_mbedtls_mpi_sub_mpi
my ($ignore, $test_name) = split("main::generate_", $sub_name);
my @cases = ();
for my $ah (@mul_mpis) {
for my $bh (@mul_mpis) {
my $a = Math::BigInt->from_hex($ah);
my $b = Math::BigInt->from_hex($bh);
next if $a > $b; # don't need to repeat test cases
my $r = $a * $b;
my $rh = $r->to_hex();
my $desc = "$test_name #NUMBER: 0x$ah * 0x$bh = 0x$rh";
my $case = output($test_name, str($ah), str($bh), str($rh));
push(@cases, [$case, $desc]);
}
}
output_cases("", @cases);
}
sub output_cases {
my ($explain, @cases) = @_;
my $count = 1;
for my $c (@cases) {
my ($case, $desc, $dep) = @$c;
$desc =~ s/NUMBER/$count/; $count++;
if (defined($explain) && $desc =~ /EXPLAIN/) {
$desc =~ s/EXPLAIN/$explain/;
$explain = "";
}
my $depends = "";
$depends = "depends_on:$dep\n" if defined($dep) && length($dep);
print <<EOF;
$desc
$depends$case
EOF
}
}
sub output {
return join(":", @_);
}
sub str {
return '"' . $_[0] . '"';
}
```
Signed-off-by: Tom Cosgrove <tom.cosgrove@arm.com>
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
Tests are refactored to generate separate cases for 32-bit and 64-bit
limbs using arch_split. Duplicate arguments and branching in the test
function is removed.
Signed-off-by: Werner Lewis <werner.lewis@arm.com>
Compare a single-limb MPI with a multi-limb MPI. This is rather ad hoc, but
will be useful for mbedtls_mpi_core_random.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
The test cases aim to mirror the legacy function, but needed the some
cases to be removed because:
- Null representation is not valid in core
- There are no negative numbers in core
- Bignum core doesn't do parameter checking and there are no promises for
even N
The _size variant of the test has been removed as bignum core doesn't do
parameter checking and there is no promises for inputs that are larger
than MBEDTLS_MPI_MAX_SIZE.
Signed-off-by: Janos Follath <janos.follath@arm.com>
Now that we have a function that calls
mbedtls_mpi_core_ct_uint_table_lookup(), the compiler won't complain if
we make it static.
Signed-off-by: Janos Follath <janos.follath@arm.com>
