Proposed specification for conditional inclusion of cryptographic
mechanism through the PSA API in Mbed TLS.
The inclusion of a mechanism is based on a declaration of boolean
symbols by the application. There is a symbol for each key type or
parametrized key type constructor, and for each algorithm or
parametrized algorithm constructor.
This is work in progress, presented for a first design discussion.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
There is little point in leaving the order in which drivers are
considered unspecified. This gives flexibility to the implementation
for a process that is generally performed at build time, not in a
constrained environment. Having a well-defined order is especially
useful with fallback.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
It's ok if they map to the same function names and an error otherwise.
It's an error to have multiple opaque drivers for the same location.
If multiple transparent drivers apply, which one applies is unspecified.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
The existing description of the syntax of capabilities also describes
the semantics of each property, but the semantics of the capability as
a whole is not immediately clear. Add a subsection that explains
precisely when a capability is applicable.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Inferring entry points from algorithms is nice in that it makes
capability specifications shorter and less redundant, but that's not
really important. It also makes capabilities more fragile: if the core
starts supporting new mechanisms based on the same algorithm (for
example, adding hash-and-sign when only sign-the-hash existed before),
a driver only supporting the old mechanisms would fail at build time.
So make entry points mandatory.
This has the benefit of making the semantics of capabilities easier to
describe.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Add the mention of key_derivation_output_key in the section about the
key derivation entry point family.
Rename "derive_key" to "key_derivation_output_key". At this point,
there's no reason to deviate from the naming convention.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Clarify some sentences. There is no change in intended meaning.
Fix typos. Change British spelling to American spelling.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Locations aren't in the official PSA API specification yet (they've
only be made public in Mbed TLS). Until version 1.0.1 of the API
specification is out, this document needs to explain locations.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Rather than have some functions take the in-memory copy of the
persistent data as argument, allow all of them to access the
persistent data, including modifying it.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Opaque drivers only have a destroy function if the key is stored in
the secure element.
Expand on how key creation works. Provide more explanations of
allocate_key in drivers for secure elements with storage. Discuss key
destruction as well.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Call the functions listed in the driver description "entry points".
It's more precise than "functions", which could also mean any C
function defined in the driver code.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Driver developer's guide: introduction on how to write a driver.
Driver integration guide: how to build Mbed TLS with drivers.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Working draft of the PSA cryptography unified interface specification.
Eventually this document will be under Arm PSA architecture ownership,
but for the time being this draft is maintained in Mbed TLS.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Rename PSA_ECC_CURVE_xxx to PSA_ECC_FAMILY_xxx, also rename
PSA_KEY_TYPE_GET_CURVE to PSA_KEY_TYPE_ECC_GET_FAMILY and rename
psa_ecc_curve_t to psa_ecc_family_t. Old defines are provided in
include/crypto_compat.h for backward compatibility.
Signed-off-by: Paul Elliott <paul.elliott@arm.com>
Clarify that using a header in library/ rather than include/ for
internal functions is a rule, not just a possibility.
As suggested by Manuel, state a rule for functions that need to be
static for best optimization but that we want to unit-test.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Evaluate possible approaches for invasive testing.
State some rules.
This commit was originally written for Mbed Crypto only.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Define constants for ECC curve families and DH group families. These
constants have 0x0000 in the lower 16 bits of the key type.
Support these constants in the implementation and in the PSA metadata
tests.
Switch the slot management and secure element driver HAL tests to the
new curve encodings. This requires SE driver code to become slightly
more clever when figuring out the bit-size of an imported EC key since
it now needs to take the data size into account.
Switch some documentation to the new encodings.
Remove the macro PSA_ECC_CURVE_BITS which can no longer be implemented.
Rename some macros and functions related to signature which are
changing as part of the addition of psa_sign_message and
psa_verify_message.
perl -i -pe '%t = (
PSA_KEY_USAGE_SIGN => PSA_KEY_USAGE_SIGN_HASH,
PSA_KEY_USAGE_VERIFY => PSA_KEY_USAGE_VERIFY_HASH,
PSA_ASYMMETRIC_SIGNATURE_MAX_SIZE => PSA_SIGNATURE_MAX_SIZE,
PSA_ASYMMETRIC_SIGN_OUTPUT_SIZE => PSA_SIGN_OUTPUT_SIZE,
psa_asymmetric_sign => psa_sign_hash,
psa_asymmetric_verify => psa_verify_hash,
); s/\b(@{[join("|", keys %t)]})\b/$t{$1}/ge' $(git ls-files . ':!:**/crypto_compat.h')
First deal with deleted files.
* Files deleted by us: keep them deleted.
* Files deleted by them, whether modified by us or not: keep our version.
```
git rm $(git status -s | sed -n 's/^DU //p')
git reset -- $(git status -s | sed -n 's/^D //p')
git checkout -- $(git status -s | sed -n 's/^ D //p')
git add -- $(git status -s | sed -n 's/^UD //p')
```
Individual files with conflicts:
* `3rdparty/everest/library/Hacl_Curve25519_joined.c`: spurious conflict because git mistakenly identified this file as a rename. Keep our version.
* `README.md`: conflict due to their change in a paragraph that doesn't exist in our version. Keep our version of this paragraph.
* `docs/architecture/Makefile`: near-identical additions. Adapt the definition of `all_markdown` and include the clean target.
* `doxygen/input/docs_mainpage.h`: conflict in the version number. Keep our version number.
* `include/mbedtls/config.h`: two delete/modify conflicts. Keep the removed chunks out.
* `library/CMakeLists.txt`: discard all their changes as they are not relevant.
* `library/Makefile`:
* Discard the added chunk about the crypto submodule starting with `INCLUDING_FROM_MBEDTLS:=1`.
* delete/modify: keep the removed chunk out.
* library build: This is almost delete/modify. Their changes are mostly not applicable. Do keep the `libmbedcrypto.$(DLEXT): | libmbedcrypto.a` order dependency.
* `.c.o`: `-o` was added on both sides but in a different place. Change to their place.
* `library/error.c`: to be regenerated.
* `library/version_features.c`: to be regenerated.
* `programs/Makefile`: Most of the changes are not relevant. The one relevant change is in the `clean` target for Windows; adapt it by removing `/S` from our version.
* `programs/test/query_config.c`: to be regenerated.
* `scripts/config.py`: added in parallel on both sides. Keep our version.
* `scripts/footprint.sh`: parallel changes. Keep our version.
* `scripts/generate_visualc_files.pl`: one delete/modify conflict. Keep the removed chunks out.
* `tests/Makefile`: discard all of their changes.
* `tests/scripts/all.sh`:
* `pre_initialize_variables` add `append_outcome`: add it.
* `pre_initialize_variables` add `ASAN_CFLAGS`: already there, keep our version.
* `pre_parse_command_line` add `--no-append-outcome`: add it.
* `pre_parse_command_line` add `--outcome-file`: add it.
* `pre_print_configuration`: add `MBEDTLS_TEST_OUTCOME_FILE`.
* Several changes in SSL-specific components: keep our version without them.
* Several changes where `config.pl` was changed to `config.py` and there was an adjacent difference: keep our version.
* Changes regarding the inclusion of `MBEDTLS_MEMORY_xxx`: ignore them here, they will be normalized in a subsequent commit.
* `component_test_full_cmake_gcc_asan`: add it without the TLS tests.
* `component_test_no_use_psa_crypto_full_cmake_asan`: keep the fixed `msg`, discard other changes.
* `component_test_memory_buffer_allocator_backtrace`, `component_test_memory_buffer_allocator`: add them without the TLS tests.
* `component_test_m32_everest`: added in parallel on both sides. Keep our version.
* `tests/scripts/check-names.sh`, `tests/scripts/list-enum-consts.pl`, `tests/scripts/list-identifiers.sh`, ``tests/scripts/list-macros.sh`: discard all of their changes.
* `tests/scripts/test-ref-configs.pl`: the change in the conflict is not relevant, so keep our version there.
* `visualc/VS2010/*.vcxproj`: to be regenerated.
Regenerate files:
```
scripts/generate_visualc_files.pl
git add visualc/VS2010/*.vcxproj
scripts/generate_errors.pl
git add library/error.c
scripts/generate_features.pl
git add library/version_features.c
scripts/generate_query_config.pl
git add programs/test/query_config.c
```
Rejected changes in non-conflicting files:
* `CMakeLists.txt`: discard their addition which has already been side-ported.
* `doxygen/mbedtls.doxyfile`: keep the version number change. Discard the changes related to `../crypto` paths.
Keep the following changes after examination:
* `.travis.yml`: all of their changes are relevant.
* `include/mbedtls/error.h`: do keep their changes. Even though Crypto doesn't use TLS errors, it must not encroach on TLS's allocated numbers.
* `tests/scripts/check-test-cases.py`: keep the code dealing with `ssl-opt.sh`. It works correctly when the file is not present.
It was not obvious before that `AES_KEY` and `RSA_KEY` were shorthand
for key material. A user copy pasting the code snippet would run into a
compilation error if they didn't realize this. Make it more obvious that
key material must come from somewhere external by making the snippets
which use global keys into functions that take a key as a parameter.
Conflict resolution:
* `scripts/config.pl`:
Take the exclusion of `MBEDTLS_PSA_CRYPTO_SE_C` from the API branch.
Take the removal of `MBEDTLS_PSA_CRYPTO_STORAGE_ITS_C` (obsolete) from
the development branch.
* `tests/scripts/all.sh`:
Multiple instances of factoring a sequence of `config.pl` calls into
a mere `config.pl baremetal` in the development branch, and a change in
the composition of `baremetal` in the API branch. In each case, take the
version from development.
* `tests/suites/test_suite_psa_crypto_slot_management.function`:
A function became non-static in development and disappeared in the API
branch. Keep the version from the API branch. Functions need to be
non-static if they're defined but unused in some configurations,
which is not the case for any function in this file at the moment.
* `tests/suites/test_suite_psa_crypto.function`:
Consecutive changes in the two branches, reconciled.
Update the storage architecture with the new features introduced for
secure element support:
* Lifetime field in key files.
* Slot number in key files for keys in a secure element.
* Transaction file (name and format).
* Persistent storage for secure element drivers (name and format).
The version number is not determined yet.
Conflicts:
* library/ssl_cli.c, library/ssl_tls.c:
Removed on the development branch. Keep them removed.
* include/psa/crypto_extra.h, library/psa_crypto_storage.c,
tests/suites/test_suite_psa_crypto.data,
tests/suites/test_suite_psa_crypto.function,
tests/suites/test_suite_psa_crypto_persistent_key.data,
tests/suites/test_suite_psa_crypto_slot_management.data,
tests/suites/test_suite_psa_crypto_slot_management.function:
Modified on the development branch only to implement the enrollment
algorithm, which has been reimplemented on the API branch.
Keep the API branch.
generate_key is a more classical name. The longer name was only
introduced to avoid confusion with getting a key from a generator,
which is key derivation, but we no longer use the generator
terminology so this reason no longer applies.
perl -i -pe 's/psa_generate_random_key/psa_generate_key/g' $(git ls-files)
Generators are mostly about key derivation (currently: only about key
derivation). "Generator" is not a commonly used term in cryptography.
So favor "derivation" as terminology. Call a generator a key
derivation operation structure, since it behaves like other multipart
operation structures. Furthermore, the function names are not fully
consistent.
In this commit, I rename the functions to consistently have the prefix
"psa_key_derivation_". I used the following command:
perl -i -pe '%t = (
psa_crypto_generator_t => "psa_key_derivation_operation_t",
psa_crypto_generator_init => "psa_key_derivation_init",
psa_key_derivation_setup => "psa_key_derivation_setup",
psa_key_derivation_input_key => "psa_key_derivation_input_key",
psa_key_derivation_input_bytes => "psa_key_derivation_input_bytes",
psa_key_agreement => "psa_key_derivation_key_agreement",
psa_set_generator_capacity => "psa_key_derivation_set_capacity",
psa_get_generator_capacity => "psa_key_derivation_get_capacity",
psa_generator_read => "psa_key_derivation_output_bytes",
psa_generate_derived_key => "psa_key_derivation_output_key",
psa_generator_abort => "psa_key_derivation_abort",
PSA_CRYPTO_GENERATOR_INIT => "PSA_KEY_DERIVATION_OPERATION_INIT",
PSA_GENERATOR_UNBRIDLED_CAPACITY => "PSA_KEY_DERIVATION_UNLIMITED_CAPACITY",
); s/\b(@{[join("|", keys %t)]})\b/$t{$1}/ge' $(git ls-files)
Read extra data from the domain parameters in the attribute structure
instead of taking an argument on the function call.
Implement this for RSA key generation, where the public exponent can
be set as a domain parameter.
Add tests that generate RSA keys with various public exponents.
Switch to the terminology "key file identifier", as has been done in
the code.
The owner uid is now in the upper 32 bits of the key file identifier,
which facilitates namespacing.
Describe the storage format for keys and random seed in Mbed Crypto
0.1.0 released with Mbed OS 5.11, over C stdio and over ITS with
32-bit file identifiers.
Describe the proposed storage format for keys and random seed in the
future release of Mbed Crypto for Mbed OS 5.12, over C stdio and over
ITS with 64-bit file identifiers.
Add new initializers for key policies and use them in our docs, example
programs, tests, and library code. Prefer using the macro initializers
due to their straightforwardness.