The first half of the table is not used, let's reuse index 0 for the
result instead of appending it in the end.
Signed-off-by: Janos Follath <janos.follath@arm.com>
The table size was set before the configured window size bound was
applied which lead to out of bounds access when the configured window
size bound is less.
Signed-off-by: Janos Follath <janos.follath@arm.com>
The window size starts giving diminishing returns around 6 on most
platforms and highly unlikely to be more than 31 in practical use cases.
Still, compilers and static analysers might complain about this and
better to be pedantic.
Co-authored-by: Gilles Peskine <gilles.peskine@arm.com>
Signed-off-by: Janos Follath <janos.follath@arm.com>
With small exponents (for example, when doing RSA-1024 with CRT, each
prime is 512 bits and we'll use wsize = 5 which may be smaller that the
maximum - or even worse when doing public RSA operations which typically
have a 16-bit exponent so we'll use wsize = 1) the usage of W will have
pre-computed values, then empty space, then the accumulator at the very
end.
Move X next to the precomputed values to make accesses more efficient
and intuitive.
Signed-off-by: Janos Follath <janos.follath@arm.com>
Elements of W didn't all have the same owner: all were owned by this
function, except W[x_index]. It is more robust if we make a proper copy
of X.
Signed-off-by: Janos Follath <janos.follath@arm.com>
Out of window zeroes were doing squaring on the output variable
directly. This leaks the position of windows and the out of window
zeroes.
Loading the output variable from the table in constant time removes this
leakage.
Signed-off-by: Janos Follath <janos.follath@arm.com>
It might happen that the psa_pake_output() function returns
elements which are not exactly 32 or 65 bytes as expected, but
1 bytes less.
As a consequence, insted of hardcoding the expected value for
the length in the output buffer, we write the correct one as
obtained from psa_pake_output()
Signed-off-by: Valerio Setti <vsetti@baylibre.com>
NEW_SESSION_TICKETS* are processed in handshake_step.
Change the stop condition from `mbedtls_ssl_is_handshake_over`
to directly check.
Signed-off-by: Jerry Yu <jerry.h.yu@arm.com>
Inlined functions might cause the compiled code to have different sizes
depending on the usage and this not acceptable in some cases.
Therefore read/write functions used in the initial key exchange are
moved to a standard C file.
Signed-off-by: Valerio Setti <vsetti@baylibre.com>
The value of the first sent signature algorithm is overwritten.
This test forces only a single algorithm to be sent and then
validates that the client received such algorithm.
04 03 is the expected value for SECP256R1_SHA256.
Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
Fix bug whereby the supported signature algorithm list sent by the
server in the certificate request would not leave enough space for the
length to be written, and thus the first element would get overwritten,
leaving two random bytes in the last entry.
Signed-off-by: Paul Elliott <paul.elliott@arm.com>