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 TEST_EQUAL fails, show the two numerical values in the test log (only
with host_test). The values are printed in hexa and signed decimal.
The arguments of TEST_EQUAL must now be integers, not pointers or floats.
The current implementation requires them to fit in unsigned long long
Signed values no larger than long long will work too. The implementation
uses unsigned long long rather than uintmax_t to reduce portability
concerns. The snprintf function must support "%llx" and "%lld".
For this purpose, add room for two lines of text to the mbedtls_test_info
structure. This adds 154 bytes of global data.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
This was causing some tests using the openssl s_client to not connect -
I suspect this was due to localhost (at least on my machine) resolving
to ::1 rather than 127.0.0.1. Note that the error seen would have been
that the session file specified with -sess_out did not get created.
Signed-off-by: Paul Elliott <paul.elliott@arm.com>
Missing wildcards meant that some servers were not identified as DTLS,
which lead to port checking on TCP rather than UDP, and thus mistakenly
cancelling tests as the server had not come up.
Signed-off-by: Paul Elliott <paul.elliott@arm.com>
This information was already present in SECURITY.md and SUPPORT.md, but that
wasn't very apparent.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Don't default to unbridled -j, which causes a load spike and isn't really
faster.
"Number of CPUs" is implemented here as a reasonable compromise between
portability, correctness and simplicity. This is just a default that can be
overridden by setting MAKEFLAGS in the environment.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
The previous implementation was misparsed in constructs like
`if (condition) MBEDTLS_IGNORE_RETURN(...); else ...;`.
Implement it as an expression, tested with GCC, Clang and MSVC.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
This macro is introduced here for use in deprecated functions. It may also
be useful in user code, so it is in a public header.
Signed-off-by: Mateusz Starzyk <mateusz.starzyk@mobica.com>
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
MBEDTLS_CHECK_RETURN_TYPICAL defaults off, but is enabled if
MBEDTLS_CHECK_RETURN_WARNING is enabled at compile time.
(MBEDTLS_CHECK_RETURN_CRITICAL is always enabled.)
The default is off so that a plausible program that builds with one version
of Mbed TLS in the default configuration will still build under the next
version.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
This is normally equivalent, but works even if some other header defines a
macro called warn_unused_result.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
An empty expansion is possible, but as documented its effect is to disable
the feature, so that isn't a good example. Instead, use the GCC
implementation as the default: it's plausible that it could work even on
compilers that don't advertise themselves as sufficiently GCC-like to define
__GNUC__, and if not it gives users a concrete idea of what the macro is
supposed to do.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
For all of these functions, the only possible failures are a hardware
accelerator (not possible unless using an ALT implementation), an internal
error or runtime corruption.
Exception: the self-tests, which serve little purpose if their status isn't
tested.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Define macros MBEDTLS_CHECK_RETURN_CRITICAL, MBEDTLS_CHECK_RETURN_TYPICAL
and MBEDTLS_CHECK_RETURN_OPTIONAL so that we can indicate on a
function-by-function basis whether checking the function's return value is
almost always necessary (CRITICAL), typically necessary in portable
applications but unnecessary in some reasonable cases (TYPICAL), or
typically unnecessary (OPTIONAL).
Update the documentation of MBEDTLS_CHECK_RETURN accordingly. This is split
between the user documentation (Doxygen, in config.h) and the internal
documentation (non-Doxygen, in platform_util.h, of minor importance since
the macro isn't meant to be used directly).
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
