When `MBEDTLS_PLATFORM_C` is not enabled, our PSA Crypto implementation
depends on the standard C library for functions like snprintf() and
exit(). However, our implementation was not including the proper header
files nor redefining all `mbedtls_*` symbols properly to ensure
successful builds without MBEDTLS_PLATFORM_C. Add the necessary header
files and macro definitions to our PSA Crypto implementation.
When MBEDTLS_CHECK_PARAMS is enabled, it's required to have an
implementation of mbedtls_param_failed() present. Without it in the PSA
examples, building the PSA examples will result in linker errors like
the following.
../../library/libmbedcrypto.a(rsa.c.o): In function `mbedtls_rsa_import':
rsa.c:(.text+0x9fd): undefined reference to `mbedtls_param_failed'
../../library/libmbedcrypto.a(rsa.c.o): In function `mbedtls_rsa_import_raw':
rsa.c:(.text+0xb0b): undefined reference to `mbedtls_param_failed'
../../library/libmbedcrypto.a(rsa.c.o): In function `mbedtls_rsa_complete':
rsa.c:(.text+0xe63): undefined reference to `mbedtls_param_failed'
../../library/libmbedcrypto.a(rsa.c.o): In function `mbedtls_rsa_export_raw':
rsa.c:(.text+0xfee): undefined reference to `mbedtls_param_failed'
../../library/libmbedcrypto.a(rsa.c.o): In function `mbedtls_rsa_export':
rsa.c:(.text+0x116f): undefined reference to `mbedtls_param_failed'
../../library/libmbedcrypto.a(rsa.c.o):rsa.c:(.text+0x1304): more undefined
references to `mbedtls_param_failed' follow
collect2: error: ld returned 1 exit status
programs/psa/CMakeFiles/crypto_examples.dir/build.make:97: recipe for target
'programs/psa/crypto_examples' failed
make[2]: *** [programs/psa/crypto_examples] Error 1
Add an implementation of mbedtls_param_failed() to the PSA Crypto
examples to avoid getting this error on the PSA examples.
Mbed TLS has deprecated a few module specific error codes in favor of
more general-purpose or cross-module error codes. Use these new error
codes instead of the deprecated error codes.
Silence a compiler warning about implicit fallthrough by using a comment
format the compiler understand to mean that the fallthrough is
intentional.
In file included from library/cipher.c:63:0:
include/mbedtls/psa_util.h: In function ‘mbedtls_psa_translate_cipher_mode’:
include/mbedtls/psa_util.h:91:15: error: this statement may fall through [-Werror=implicit-fallthrough=]
if( taglen == 0 )
^
include/mbedtls/psa_util.h:94:9: note: here
default:
^~~~~~~
cc1: all warnings being treated as errors
$ gcc --version
gcc (Ubuntu 7.3.0-27ubuntu1~18.04) 7.3.0
Copyright (C) 2017 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
Copy our include/mbedtls/config.h file, which is our default
configuration, to configs/config-psa-crypto.h, updating what was
previously there to the latest defaults.
Resolve conflicts by performing the following.
- Take the upstream Mbed TLS ChangeLog verbatim.
- Reject changes to Makefiles and CMake that are related to using Mbed
Crypto as a submodule. It doesn't make sense to use Mbed Crypto as a
submodule of itself.
- Reject README changes, as Mbed Crypto has its own, different README.
- Reject PSA-related changes to config.h. We don't want to disable the
availability of the PSA Crypto API by default in the Mbed Crypto
config.h.
- Don't inadvertently revert dead code removal in
mbedtls_cipher_write_tag() which was added in f2a7529403 ("Fix
double return statement in cipher.c")
- Where Mbed Crypto already had some MBEDTLS_USE_PSA_CRYPTO code (from
past companion PRs) take the latest version from Mbed TLS which
includes integration with MBEDTLS_CHECK_PARAMS.
- Update the version of the shared library files to match what's
currently present in Mbed TLS.
- Reject removal of testing with PSA from config full tests.
- Resolve conflicts in test tests/suites/helpers.function, where both
Mbed Crypto and Mbed TLS both added documentation for TEST_ASSERT.
Combine text from both documentation efforts.
- Reject adding a submodule of ourselves.
- Reject addition of submodule tests in all.sh.
- Reject addition of submodule to library path in
tests/scripts/run-test-suites.pl.
- Avoid using USE_CRYPTO_SUBMODULE=1 in
component_test_use_psa_crypto_full_cmake_asan() in all.sh.
When using PSA with MBEDTLS_ENTROPY_NV_SEED, some test suites
require the seed file for PSA initialization, which was normally generated
later, when entropy tests were run. This change creates an initial seedfile
in all.sh.
Some of the types may in principle be wider than `unsigned`, so use
`unsigned long` in printf.
Add support for signed types: a status is a signed value, and
preferentially printed in decimal.
Don't unconditionally enable PSA Crypto for all tests. Only enable it in
tests that require it. This allows crypto tests to check that
psa_crypto_init() fails when it is supposed to fail, since we want to
perform some action in a test, and then call psa_crypto_init() and check
the result without it having been called previously.
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.
Set the CMake-observed variable `CTEST_OUTPUT_ON_FAILURE`, so that when
a "make test" run by CMake fails, verbose test output about the detail
of failure is available.
Enable handling of zero-length null output in PKCS1 v1.5 decryption.
Prevent undefined behavior by avoiding a memcpy() to zero-length null
output buffers.
In mbedtls_rsa_rsaes_oaep_encrypt and
mbedtls_rsa_rsaes_pkcs1_v15_encrypt, if the input length is 0 (which
is unusual and mostly useless, but permitted) then it is fine for the
input pointer to be NULL. Don't return an error in this case.
When `input` is NULL, `memcpy( p, input, ilen )` has undefined behavior
even if `ilen` is zero. So skip the `memcpy` call in this case.
Likewise, in `mbedtls_rsa_rsaes_oaep_decrypt`, skip the `memcpy` call if
`*olen` is zero.
Context: During a handshake, the SSL/TLS handshake logic constructs
an instance of ::mbedtls_ssl_session representing the SSL session
being established. This structure contains information such as the
session's master secret, the peer certificate, or the session ticket
issues by the server (if applicable).
During a renegotiation, the new session is constructed aside the existing
one and destroys and replaces the latter only when the renegotiation is
complete. While conceptually clear, this means that during the renegotiation,
large pieces of information such as the peer's CRT or the session ticket
exist twice in memory, even though the original versions are removed
eventually.
This commit removes the simultaneous presence of two peer CRT chains
in memory during renegotiation, in the following way:
- Unlike in the case of SessionTickets handled in the previous commit,
we cannot simply free the peer's CRT chain from the previous handshake
before parsing the new one, as we need to verify that the peer's end-CRT
hasn't changed to mitigate the 'Triple Handshake Attack'.
- Instead, we perform a binary comparison of the original peer end-CRT
with the one presented during renegotiation, and if it succeeds, we
avoid re-parsing CRT by moving the corresponding CRT pointer from the
old to the new session structure.
- The remaining CRTs in the peer's chain are not affected by the triple
handshake attack protection, and for them we may employ the canonical
approach of freeing them before parsing the remainder of the new chain.
Note that this commit intends to not change any observable behavior
of the stack. In particular:
- The peer's CRT chain is still verified during renegotiation.
- The tail of the peer's CRT chain may change during renegotiation.
Context: During a handshake, the SSL/TLS handshake logic constructs
an instance of ::mbedtls_ssl_session representing the SSL session
being established. This structure contains information such as the
session's master secret, the peer certificate, or the session ticket
issues by the server (if applicable).
During a renegotiation, the new session is constructed aside the existing
one and destroys and replaces the latter only when the renegotiation is
complete. While conceptually clear, this means that during the renegotiation,
large pieces of information such as the peer's CRT or the session ticket
exist twice in memory, even though the original versions are removed
eventually.
This commit starts removing this memory inefficiency by freeing the old
session's SessionTicket before the one for the new session is allocated.
The existing test `x509parse_crt()` for X.509 CRT parsing
so far used the generic parsing API `mbedtls_x509_crt_parse()`
capable of parsing both PEM encoded and DER encoded certficates,
but was actually only used with DER encoded input data. Moreover,
as the purpose of the test is the testing of the core DER X.509 parsing
functionality, not the PEM vs. DER dispatch (which is now already tested
in the various `x509_crt_info()` tests), the call can be replaced with a
direct call to `mbedtls_x509_parse_crt_der()`.
This commit does that, and further adds to the test an analogous
call to the new API `mbedtls_x509_parse_crt_der_nocopy()` to test
copyless parsing of X.509 certificates.
Context:
The existing API `mbedtls_x509_parse_crt_der()` for parsing DER
encoded X.509 CRTs unconditionally makes creates a copy of the
input buffer in RAM. While this comes at the benefit of easy use,
-- specifically: allowing the user to free or re-use the input
buffer right after the call -- it creates a significant memory
overhead, as the CRT is duplicated in memory (at least temporarily).
This might not be tolerable a resource constrained device.
As a remedy, this commit adds a new X.509 API call
`mbedtls_x509_parse_crt_der_nocopy()`
which has the same signature as `mbedtls_x509_parse_crt_der()`
and almost the same semantics, with one difference: The input
buffer must persist and be unmodified for the lifetime of the
established instance of `mbedtls_x509_crt`, that is, until
`mbedtls_x509_crt_free()` is called.
Resolve incompatibilties in the RSA module where changes made for
parameter validation prevent Mbed Crypto from working. Mbed Crypto
depends on being able to pass zero-length buffers that are NULL to RSA
encryption functions.
This reverts commit 2f660d047d.
