The refactoring is needed for the group api to work
properly. Code is modified to use mbedtls_get_supported_groups
instead of direct access so that both deprecated and new api
are useable.
Signed-off-by: Brett Warren <brett.warren@arm.com>
mbedtls_ssl_conf_groups allows supported groups for key
sharing to be configured via their IANA NamedGroup ID.
This is added in anticipation of PQC and Hybrid key
sharing algorithms being integrated into Mbed TLS.
mbedtls_ssl_conf_curves is deprecated in favor of
mbedtls_ssl_conf_groups. handshake_init has been
modified to translate and copy curves configured
via conf_curves into a heap allocatied array of
NamedGroup IDs. This allows the refactoring of code
interacting with conf_curve related variables (such
as curve_list) to use NamedGroup IDs while retaining
the deprecated API.
Signed-off-by: Brett Warren <brett.warren@arm.com>
To test c <= high, instead of testing the sign of (high + 1) - c, negate the
sign of high - c (as we're doing for c - low). This is a little easier to
read and shaves 2 instructions off the arm thumb build with
arm-none-eabi-gcc 7.3.1.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
n was used for two different purposes. Give it a different name the second
time. This does not seem to change the generated code when compiling with
optimization for size or performance.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Instead of doing constant-flow table lookup, which requires 64 memory loads
for each lookup into a 64-entry table, do a range-based calculation, which
requires more CPU instructions per range but there are only 5 ranges.
I expect a significant performance gain (although smaller than for decoding
since the encoding table is half the size), but I haven't measured. Code
size is slightly smaller.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Document what each local variable does when it isn't obvious from the name.
Don't reuse a variable for different purposes.
This commit has very little impact on the generated code (same code size on
a sample Thumb build), although it does fix a theoretical bug that 2^32
spaces inside a line would be ignored instead of treated as an error.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Instead of doing constant-flow table lookup, which requires 128 memory loads
for each lookup into a 128-entry table, do a range-based calculation, which
requires more CPU instructions per range but there are only 5 ranges.
Experimentally, this is ~12x faster on my PC (based on
programs/x509/load_roots). The code is slightly smaller, too.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Base64 decoding uses equality comparison tests for characters that don't
leak information about the content of the data other than its length, such
as whitespace. Do this with '=' as well, since it only reveals information
about the length. This way the table lookup can focus on character validity
and decoding value.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
When the option is On, CMake will have rules to generate the generated
files using scripts etc. When the option is Off, CMake will assume the
files are available from the source tree; in that mode, it won't require
any extra tools (Perl for example) compared to when we committed the
files to git.
The intention is that users will never need to adjust this option:
- in the development branch (and features branches etc.) the option is
always On (development mode);
- in released tarballs, which include the generated files, we'll switch
the option to Off (release mode) in the same commit that re-adds the
generated files.
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
