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13467 commits

Author SHA1 Message Date
irwir 672257b7d9 Add changelog entry
Signed-off-by: irwir <irwir@users.noreply.github.com>
2020-06-09 15:03:03 +03:00
Janos Follath 3c4a46c44a
Merge pull request #3398 from gilles-peskine-arm/montmul-cmp-branch-development
Remove a secret-dependent branch in Montgomery multiplication
2020-06-09 12:40:51 +01:00
Bence Szépkúti 5620d71d58 Remove hardcoded line number from the zeroize test
Instead, we insert a comment containing GDB_BREAK_HERE in the line we
want to break at, and let the gdb script search for it.

Signed-off-by: Bence Szépkúti <bence.szepkuti@arm.com>
2020-06-09 12:52:04 +02:00
Gilles Peskine 09ec10a32e Clean up some comments
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2020-06-09 10:39:38 +02:00
Gilles Peskine 0e5faf6407 mbedtls_mpi_sub_abs: check the range of the result when it happens
The function mbedtls_mpi_sub_abs first checked that A >= B and then
performed the subtraction, relying on the fact that A >= B to
guarantee that the carry propagation would stop, and not taking
advantage of the fact that the carry when subtracting two numbers can
only be 0 or 1. This made the carry propagation code a little hard to
follow.

Write an ad hoc loop for the carry propagation, checking the size of
the result. This makes termination obvious.

The initial check that A >= B is no longer needed, since the function
now checks that the carry propagation terminates, which is equivalent.
This is a slight performance gain.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2020-06-08 22:50:35 +02:00
Gilles Peskine 221626f2d3 Simplify the final reduction in mpi_montmul
There was some confusion during review about when A->p[n] could be
nonzero. In fact, there is no need to set A->p[n]: only the
intermediate result d might need to extend to n+1 limbs, not the final
result A. So never access A->p[n]. Rework the explanation of the
calculation in a way that should be easier to follow.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2020-06-08 22:37:50 +02:00
Gilles Peskine c097e9ea45 Move carry propagation out of mpi_sub_hlp
The function mpi_sub_hlp had confusing semantics: although it took a
size parameter, it accessed the limb array d beyond this size, to
propagate the carry. This made the function difficult to understand
and analyze, with a potential buffer overflow if misused (not enough
room to propagate the carry).

Change the function so that it only performs the subtraction within
the specified number of limbs, and returns the carry.

Move the carry propagation out of mpi_sub_hlp and into its caller
mbedtls_mpi_sub_abs. This makes the code of subtraction very slightly
less neat, but not significantly different.

In the one other place where mpi_sub_hlp is used, namely mpi_montmul,
this is a net win because the carry is potentially sensitive data and
the function carefully arranges to not have to propagate it.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2020-06-08 22:08:21 +02:00
Gilles Peskine 37ecc61836 More logical parameter order for mpi_sub_hlp
mpi_sub_hlp performs a subtraction A - B, but took parameters in the
order (B, A). Swap the parameters so that they match the usual
mathematical syntax.

This has the additional benefit of putting the output parameter (A)
first, which is the normal convention in this module.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2020-06-08 22:05:13 +02:00
Steven Cooreman 223f2877be Add test to check that volatile external keys do not get persisted
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-06-08 18:35:16 +02:00
Steven Cooreman bbeaf18eac Do not persist transactions on volatile external keys
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-06-08 18:29:44 +02:00
Steven Cooreman c59de6ab7e Refactor lifetime checking to reflect split in location and persistence
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-06-08 18:28:25 +02:00
Steven Cooreman 8335f41cda Enable figuring out number of cores when running on OS X
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-06-08 18:20:08 +02:00
Steven Cooreman db06445ad6 Fix typo in currently unused macro constant
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-06-08 18:19:33 +02:00
Manuel Pégourié-Gonnard e050191ef5 Make basic-build-test.sh deterministic
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-06-08 13:04:10 +02:00
Manuel Pégourié-Gonnard 304b099534 all.sh: clean up some uses of "local" variables
While pure sh doesn't have a concept of local variables, we can partially
emulate them by unsetting variables before we exit the function, and use the
convention of giving them lowercase names to distinguish from global
variables.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-06-08 11:01:59 +02:00
Manuel Pégourié-Gonnard f1f180a6a1 all.sh: keep dd output in non-quiet mode
Since dd prints everything on stderr, both normal status update and actual
errors when they occur, redirecting that to /dev/null is a trade-off that's
acceptable in quiet mode (typically used on a developer's machine and the
developer will re-run in non-quiet mode if anything fails without sufficient
detail in the output), but not that much in non-quiet mode.

For example, if our dd invocation fails because the disk in full on a CI
machine, we want the error to be reported at the time we invoke dd, and not
later when a seemingly unrelated test fails due to an incorrect seedfile.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-06-08 10:46:35 +02:00
Manuel Pégourié-Gonnard 21b3d12066
Merge pull request #3374 from danh-arm/dh/branch-cov
Enable branch coverage in basic_build_test.sh
2020-06-08 10:15:06 +02:00
Manuel Pégourié-Gonnard 9b8d34edd4 Avoid superflous randomization with restartable
Checking the budget only after the randomization is done means sometimes we
were randomizing first, then noticing we ran out of budget, return, come back
and randomize again before we finally normalize.

While this is fine from a correctness and security perspective, it's a minor
inefficiency, and can also be disconcerting while debugging, so we might as
well avoid it.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-06-08 09:53:20 +02:00
Manuel Pégourié-Gonnard d53ef2ffd1 Use HMAC_DRBG by default for ECP internal DRBG
It results in smaller code than using CTR_DRBG (64 bytes smaller on ARMv6-M
with arm-none-eabi-gcc 7.3.1), so let's use this by default when both are
available.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-06-08 09:10:11 +02:00
Manuel Pégourié-Gonnard 22b1de3097 Skip redundant checks for NULL f_rng
Unless MBEDTLS_ECP_NO_INTERNAL_RNG is defined, it's no longer possible for
f_rng to be NULL at the places that randomize coordinates.

Eliminate the NULL check in this case:
- it makes it clearer to reviewers that randomization always happens (unless
  the user opted out at compile time)
- a NULL check in a place where it's easy to prove the value is never NULL
  might upset or confuse static analyzers (including humans)
- removing the check saves a bit of code size

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-06-08 09:09:20 +02:00
Manuel Pégourié-Gonnard c721178487 Add Security ChangeLog entry for lack of blinding
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-06-08 09:09:20 +02:00
Manuel Pégourié-Gonnard 71d56678d1 Update documentation about optional f_rng parameter
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-06-08 09:09:20 +02:00
Manuel Pégourié-Gonnard 53fb66db12 Add support for RESTARTABLE with internal RNG
Currently we draw pseudo-random numbers at the beginning and end of the main
loop. With ECP_RESTARTABLE, it's possible that between those two occasions we
returned from the multiplication function, hence lost our internal DRBG
context that lives in this function's stack frame. This would result in the
same pseudo-random numbers being used for blinding in multiple places. While
it's not immediately clear that this would give rise to an attack, it's also
absolutely not clear that it doesn't. So let's avoid that by using a DRBG
context that lives inside the restart context and persists across
return/resume cycles. That way the RESTARTABLE case uses exactly the
same pseudo-random numbers as the non-restartable case.

Testing and compile-time options:

- The case ECP_RESTARTABLE && !ECP_NO_INTERNAL_RNG is already tested by
  component_test_no_use_psa_crypto_full_cmake_asan.
- The case ECP_RESTARTABLE && ECP_NO_INTERNAL_RNG didn't have a pre-existing
  test so a component is added.

Testing and runtime options: when ECP_RESTARTABLE is enabled, the test suites
already contain cases where restart happens and cases where it doesn't
(because the operation is short enough or because restart is disabled (NULL
restart context)).

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-06-08 09:09:20 +02:00
Manuel Pégourié-Gonnard f2a9fcff62 Move internal drbg init to specific mul functions
While it seems cleaner and more convenient to set it in the top-level
mbedtls_ecp_mul() function, the existence of the restartable option changes
things - when it's enabled the drbg context needs to be saved in the restart
context (more precisely in the restart_mul sub-context), which can only be
done when it's allocated, which is in the curve-specific mul function.

This commit only internal drbg management from mbedtls_ecp_mul() to
ecp_mul_mxz() and ecp_mul_comb(), without modifying behaviour (even internal),
and a future commit will modify the ecp_mul_comb() version to handle restart
properly.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-06-08 09:09:20 +02:00
Manuel Pégourié-Gonnard c52a43c2bd Implement use of internal DRBG for ecp_mul()
The case of MBEDTLS_ECP_RESTARTABLE isn't handled correctly yet: in that case
the DRBG instance should persist when resuming the operation. This will be
addressed in the next commit.

When both CTR_DRBG and HMAC_DRBG are available, CTR_DRBG is preferred since
both are suitable but CTR_DRBG tends to be faster and I needed a tie-breaker.

There are currently three possible cases to test:

- NO_INTERNAL_RNG is set -> tested in test_ecp_no_internal_rng
- it's unset and CTR_DRBG is available -> tested in the default config
- it's unset and CTR_DRBG is disabled -> tested in
  test_ecp_internal_rng_no_ctr_drbg

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-06-08 09:09:20 +02:00
Manuel Pégourié-Gonnard 1a3f9edc08 Add config.h option MBEDTLS_ECP_NO_INTERNAL_RNG
No effect so far, except on dependency checking, as the feature it's meant to
disable isn't implemented yet (so the descriptions in config.h and the
ChangeLog entry are anticipation for now).

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-06-08 09:09:20 +02:00
Manuel Pégourié-Gonnard 1fc09be3ea Merge branch 'development' into development-restricted
* development: (44 commits)
  Add test for dependencies on HMAC_DRBG in all.sh
  Fix undeclared dep on deterministic ECDSA in test
  Document precondition of nonce-generating function in ssl_msg.c
  Improve documentation of nonce-generating function in ssl_msg.c
  Spell out check for non-zero'ness
  Fix debug print of explicit IV
  Fix indentation in debug statement in ssl_msg.c
  Fix typo in check_config.h
  Mention HKDF in TLS 1.3 feature document
  Fix typo in header of TLS 1.3 experimental features document
  Add dependencies for experimental TLS 1.3 features in check_config.h
  Rename TLS 1.3 padding granularity macro
  Add documentation on state of upstreaming of TLS 1.3 prototype
  Change TLS 1.3 default padding to no padding
  Update query_config.c
  Fix #endif indicator comment
  Add missing configuration guards to SSL record protection helpers
  Introduce configuration option for TLS 1.3 padding granularity
  Fix copy-pasta in TLS 1.3 record protection unit test names
  Fix Changelag PR number and uniformize code when prng fails
  ...
2020-06-08 09:09:04 +02:00
Manuel Pégourié-Gonnard a7f6d25e12
Merge pull request #3400 from mpg/fix-hmac-drbg-deps-dev
Fix undeclared dependencies on HMAC_DRBG and add test
2020-06-05 11:50:02 +02:00
Manuel Pégourié-Gonnard e860fef438
Merge pull request #3318 from Jonas4420/development
Fix potential memory leak in EC multiplication
2020-06-05 11:43:52 +02:00
Gilles Peskine 026f555df3 Explicitly cast down from mbedtls_mpi_uint to unsigned char
Let code analyzers know that this is deliberate. For example MSVC
warns about the conversion if it's implicit.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2020-06-05 10:48:25 +02:00
Manuel Pégourié-Gonnard 5b942dc45e Add test for dependencies on HMAC_DRBG in all.sh
Similarly to the recently-added tests for dependencies on CTR_DRBG:
constrained environments will probably want only one DRBG module, and we
should make sure that tests pass in such a configuration.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-06-05 09:29:51 +02:00
Manuel Pégourié-Gonnard c03d499a58 Fix undeclared dep on deterministic ECDSA in test
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-06-05 09:21:49 +02:00
Gilles Peskine d55bfe962a Add changelog entry: fix #3394
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2020-06-04 21:55:23 +02:00
Gilles Peskine 132c0976e9 Remove a secret-dependent branch in Montgomery multiplication
In mpi_montmul, an auxiliary function for modular
exponentiation (mbedtls_mpi_mod_exp) that performs Montgomery
multiplication, the last step is a conditional subtraction to force
the result into the correct range. The current implementation uses a
branch and therefore may leak information about secret data to an
adversary who can observe what branch is taken through a side channel.

Avoid this potential leak by always doing the same subtraction and
doing a contant-trace conditional assignment to set the result.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2020-06-04 21:55:23 +02:00
Gilles Peskine f04d11e8b2 Separate out low-level mpi_safe_cond_assign
Separate out a version of mpi_safe_cond_assign that works on
equal-sized limb arrays, without worrying about allocation sizes or
signs.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2020-06-04 21:55:23 +02:00
Gilles Peskine 2a82f72703 Document some internal bignum functions
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2020-06-04 21:55:23 +02:00
Gilles Peskine 4e91d473c3 Revert "Shut up a clang-analyzer warning"
This reverts commit 2cc69fffcf.

A check was added in mpi_montmul because clang-analyzer warned about a
possibly null pointer. However this was a false positive. Recent
versions of clang-analyzer no longer emit a warning (3.6 does, 6
doesn't).

Incidentally, the size check was wrong: mpi_montmul needs
T->n >= 2 * (N->n + 1), not just T->n >= N->n + 1.

Given that this is an internal function which is only used from one
public function and in a tightly controlled way, remove both the null
check (which is of low value to begin with) and the size check (which
would be slightly more valuable, but was wrong anyway). This allows
the function not to need to return an error, which makes the source
code a little easier to read and makes the object code a little
smaller.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2020-06-04 21:55:17 +02:00
Gilles Peskine 742f1a4528 Add a const annotation to the non-changing argument of mpi_sub_mul
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2020-06-04 20:53:57 +02:00
Janos Follath bba4c17b7a
Merge pull request #3315 from hanno-arm/tls13-experimental-macro
Add support for TLS 1.3 record protection routines
2020-06-04 15:51:54 +01:00
Hanno Becker f486e28694 Document precondition of nonce-generating function in ssl_msg.c
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-06-04 13:33:08 +01:00
Hanno Becker 15952814d8 Improve documentation of nonce-generating function in ssl_msg.c
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-06-04 13:31:46 +01:00
Hanno Becker 1cda2667af Spell out check for non-zero'ness
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-06-04 13:28:44 +01:00
Hanno Becker 16bf0e2346 Fix debug print of explicit IV
The previous version attempted to write the explicit IV from
the destination buffer before it has been written there.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-06-04 13:27:34 +01:00
Hanno Becker 7cca3589cb Fix indentation in debug statement in ssl_msg.c
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-06-04 13:27:22 +01:00
Manuel Pégourié-Gonnard b06d88387e Merge branch 'development' into development-restricted
* development: (44 commits)
  Add test for building without CTR_DRBG
  Add usage info of generate_psa_constants script
  Fix undeclared deps on CTR_DRBG in programs/fuzz
  Fix undeclared deps on MBEDTLS_CTR_DRBG in tests
  Finish the documentation of normalize_path
  Generate PSA constant names in CMake build dir
  Run assemble_changelog.py in all.sh
  Wrap line to 79 columns
  Some .pem files are openssl output and have tabs and that's ok
  .dsw files are Visual Studio stuff
  Permit empty files
  Normalize line endings
  Check only files checked into Git
  Exclude binary files from text checks
  Regex mechanism for check-specific exemptions
  Check all files by default
  More accurate variable name
  Fix article in documentation
  Add output of `python3` version
  Add output of make and cmake versions
  ...
2020-06-03 11:39:24 +02:00
Manuel Pégourié-Gonnard 6abc20e0e3
Merge pull request #3378 from mpg/fix-ctr-drbg-deps
Fix undeclared dependencies on CTR_DRBG (and add test)
2020-06-03 10:55:52 +02:00
Gilles Peskine d6916d74c5
Merge pull request #3121 from gilles-peskine-arm/invasive_testing_strategy-crypto
Invasive testing strategy

Create a new header `common.h`.

Introduce a configuration option `MBEDTLS_TEST_HOOKS` for test-specific code, to be used in accordance with the invasive testing strategy.
2020-06-02 16:55:48 +02:00
Gilles Peskine 73b394290a
Merge pull request #3367 from hug-dev/psa-constants-in-build-dir
Generate PSA constant names in CMake build dir
2020-06-02 12:29:46 +02:00
Manuel Pégourié-Gonnard 129e13cb12 Use all.sh in pre-push hook
The list in the pre-push hook was redundant with the list of `check_*`
components in all.sh, and unsurprisingly it was outdated.

Missing components were:

- check_recursion
- check_changelog
- check_test_cases
- check_python_files
- check_generate_test_code

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-06-02 11:56:26 +02:00
Manuel Pégourié-Gonnard a9119167e0 Make component_check_test_cases more -q frienly
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-06-02 11:52:14 +02:00