Commit Graph

377 Commits

Author SHA1 Message Date
Piotr Nowicki
e048b91d25 Add returning a FAULT_DETECTED error on suspected FI attacks
The change applies to the places where we prevent double synchronous
FI attacks with random delay, and where we do not respond to their
detection. The response to such an attack should be to return the
appropriate error code.

Signed-off-by: Piotr Nowicki <piotr.nowicki@arm.com>
2020-06-09 12:00:42 +02:00
Andrzej Kurek
825ebd483f
Merge mbedtls 2.16.6 into baremetal
Conflicts:
mbedtls.doxyfile - PROJECT_NAME - mbed TLS v2.16.6 chosen.
doc_mainpage.h - mbed TLS v2.16.6 version chosen.
hmac_drbg.h - line 260, extended description chosen.
            - line 313, extended description chosen.
            - line 338, extended description chosen.
version.h - 2.16.6 chosen.
CMakeLists.txt - 2.16.6 chosen.
test_suite_version.data - 2.16.6 chosen.
Makefile - 141 - manual correction - baremetal version of C_SOURCE_FILES
                 with variables for directories plus 2.16.6 CTAGS addition.
pkparse.c - lines 846 onwards - the asn1_get_nonzero_mpi implementation chosen.
ssl_tls.c - line 5269 - edited manually, left the ret=0, because baremetal has
            a different behaviour since commit 87b5626, but added a debug
            message that's new in 2.16.6.    
all.sh:
- component_build_deprecated - chosen the refactored version from 2.16.6,
                               but with extra flags from baremetal.
- rest of the _no_xxx tests - merged make options to have PTHREAD=1 and
                              other changes from 2.16.6 (like -O1 instead of -O0).
- component_build_arm_none_eabi_gcc_no_64bit_multiplication - added 
                              TINYCRYPT_BUILD=0 to the 2.16.6 version of make.

x509/req_app.c - left baremetal log but with mbedtls_exit( 0 ) call.
x509/crl_app.c - left baremetal log but with mbedtls_exit( 0 ) call.
x509/cert_app.c - left baremetal log but with mbedtls_exit( 0 ) call.
ssl/ssl_mail_client.c - left baremetal log but with mbedtls_exit( 0 ) call.
ssl/ssl_pthread_server.c - left baremetal log but with mbedtls_exit( 0 ) call.
ssl/ssl_fork_server.c - left baremetal log but with mbedtls_exit( 0 ) call.
ssl_client1.c - line 54 - left baremetal log but with mbedtls_exit( 0 ) call.
ssl_client2.c - line 54 - left baremetal log but with mbedtls_exit( 0 ) call.
              - line 132 - new options of both branches added.
              - skip close notify handled as in 2.16.6, but with `ssl` instead of `&ssl`.
              - Merged the 2.16.6 usage split with additional baremetal usages.
              - Merged options from baremetal and 2.16.6.
ssl_server.c - left baremetal log but with mbedtls_exit( 0 ) call.
ssl_server2.c - Merged the 2.16.6 usage split with additional baremetal usages.
config.pl - fixed missing defines from the documentation, removed duplicates,
            and reorganised so that the documentation and excluded list
            are ordered in the same way.
test_suite_x509parse.data - only added the two new pathlen tests.
x509_crt.c - change the return code by removing
             MBEDTLS_ERR_X509_INVALID_EXTENSIONS, since it's added by
             x509_crt_frame_parse_ext not by an "or", but by "+=".
Changelog - Assigned all entries to appropriate sections.
ssl-opt.sh - line 8263 - merged options.
           - removed lines 1165 - 1176 - there was a duplicate test, probably
             an artifact of previous merges.
check-files.py - sticked to old formatting.

Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
2020-05-18 11:47:25 -04:00
Arto Kinnunen
ac6d226939 Update signature of mbedtls_platform_random_delay
Skip parameter and return value from mbedtls_platform_random_delay
to make it more resistant for FI attacks.
2020-01-09 10:19:07 +02:00
Arto Kinnunen
e91f0dc905 Replace mbedtls_platform_enforce_volatile_reads
Replace function mbedtls_platform_enforce_volatile_reads() with
mbedtls_platform_random_delay().
2020-01-07 10:47:58 +02:00
Manuel Pégourié-Gonnard
9ca11fc892 Fix issues found by the CI
- MSVC doesn't like -1u
- We need to include platform.h for MBEDTLS_ERR_PLATFORM_FAULT_DETECTED - in
  some configurations it was already included indirectly, but not in all
configurations, so better include it directly.
2019-11-28 12:07:01 +01:00
Manuel Pégourié-Gonnard
6bdc6809da Initialise variables to failing values 2019-11-28 10:40:03 +01:00
Manuel Pégourié-Gonnard
18761926a8 Fix double-check for bad signature
In the previous version, it was enough for the attacker to glitch the
top-level 'if' to skip the entire block. We want two independent blocks here,
so that an attacker can only succeed with two successive glitches.
2019-11-21 15:32:45 +01:00
Manuel Pégourié-Gonnard
4c9b556e38 Add double-check for flags == 0 in crt_verify()
Also move to "default flow assumes failure" while at it.
2019-11-21 15:32:45 +01:00
Manuel Pégourié-Gonnard
ea7eab1fde Add redundancy (Hamming distance) to cert flags
Before this commit, if a certificate only had one issue (for example, if the
"untrusted" bit was the only set in flags), an attacker that could flip this
single bit between the moment it's set and the moment flags are checked before
returning from mbedtls_x509_crt_verify() could make the entire verification
routine appear to succeed (return 0 with no bit set in flags).

Avoid that by making sure that flags always has either 0 or at least 9 bits
set during the execution of the function. However, to preserve the API, clear
the 8 extra bits before returning. This doesn't open the door to other
attacks, as fortunately the API already had redundancy: either both flags and
the return value are 0, or flags has bits set and the return value is non-zero
with at least 16 bits set (assuming 32-bit 2-complement ints).
2019-11-21 15:32:45 +01:00
Manuel Pégourié-Gonnard
81c1fc4132 Add double check on bad signature flagging 2019-11-21 15:32:45 +01:00
Manuel Pégourié-Gonnard
f66657ac44 Use large Hamming distance for signature validity
If signature_is_good is 0 (invalid) of 1 (valid), then it's all too easy for
an active physical attacker to turn invalid into valid by flipping a single
bit in RAM, on the bus or in a CPU register.

Use a special value to represent "valid" that can't easily be reached by
flipping a few bits.
2019-11-21 15:32:45 +01:00
Manuel Pégourié-Gonnard
d1e55dfce6 Add double check on cert signature verification
x509_crt_check_signature() directly returns the return value of
pk_verify_xxx() without looking at it, so nothing to do here. But its caller
compares the value to 0, which ought to be double-checked.
2019-11-21 15:32:45 +01:00
Teppo Järvelin
91d7938761 Changed every memcpy to SCA equivalent mbedtls_platform_memcpy
This makes physical attacks more difficult.
2019-10-30 14:07:04 +02:00
Simon Butcher
e2bf54d3d1 Merge remote-tracking branch 'public/pr/2877' into baremetal 2019-10-23 14:53:29 +01:00
Simon Butcher
713e5c365d Merge remote-tracking branch 'public/pr/2880' into baremetal 2019-10-23 14:52:27 +01:00
Manuel Pégourié-Gonnard
54526c3c89 Use plain memset() for freshly allocated objects
This commits reverts to plain memset() for cases like:

    some_type foo;
    memset( &foo, 0, sizeof( foo ) );

(Sometimes there is code between declaration in memset(), but it doesn't
matter as long as it doesn't touch foo.)

The reasoning is the same as in the previous commit: the stack shouldn't
contain sensitive data as we carefully wipe it after use.
2019-10-22 10:03:07 +02:00
Manuel Pégourié-Gonnard
994193326b Use plain memset() in context init functions
We call xxx_init() on a structure when it has been freshly allocated (on the
stack or heap).

At this point it contains random-looking data none of which should be
sensitive, as all sensitive data is wiped using mbedtls_platform_zeroize()
when we're done using it and the memory area is going to be reclaimed (by
exiting the function or free()ing the buffer).
2019-10-22 10:03:07 +02:00
Manuel Pégourié-Gonnard
7a346b866c Replace memset() with mbedtls_platform_memset()
Steps:

1. sed -i 's/\bmemset(\([^)]\)/mbedtls_platform_memset(\1/g' library/*.c tinycrypt/*.c include/mbedtls/*.h scripts/data_files/*.fmt

2. Manually edit library/platform_util.c to revert to memset() in the
implementations of mbedtls_platform_memset() and mbedtls_platform_memcpy()

3. egrep -n '\<memset\>' library/*.c include/mbedtls/*.h tinycrypt/*.c
The remaining occurrences are in three categories:
    a. From point 2 above.
    b. In comments.
    c. In the initialisation of memset_func, to be changed in a future commit.
2019-10-22 10:03:07 +02:00
Teppo Järvelin
61f412eb58 Changed every memcmp to SCA equivalent mbedtls_platform_memcmp
This makes physical attacks more difficult.
Selftest memcmp functions were not changed.
2019-10-03 13:14:33 +03:00
Simon Butcher
85b495b30a Merge remote-tracking branch 'origin/pr/652' into baremetal 2019-09-25 16:37:07 +01:00
Manuel Pégourié-Gonnard
e5a0b366f8 Merge branch 'baremetal' into baremetal-2.16-20190909
* baremetal: (78 commits)
  Review corrections 6
  Review corrections 5
  Minor changes to tinycrypt README
  Typos in the tinycrypt README
  Addition of copyright statements to tinycrypt files
  Add LICENSE and README for tinycrypt
  Add SPDX lines to each imported TinyCrypt file
  Review corrections 4
  Review corrections 3
  Review corrections 2
  Review corrections
  Update signature of BE conversion functions
  Use function for 16/24/32-bit BE conversion
  x509.c: Minor readability improvement
  x509_crt.c: Indicate guarding condition in #else branch
  X.509: Don't remove verify callback by default
  Fix Doxygen warnings regarding removed verify cb+ctx parameters
  ECC restart: Use optional verification mode in bad signature test
  Re-implement verify chain if vrfy cbs are disabled
  Add zero-cost abstraction layer for CRT verification chain
  ...
2019-09-12 09:58:14 +02:00
Simon Butcher
88b535a47e Merge remote-tracking branch 'origin/pr/654' into baremetal 2019-09-10 14:54:28 +01:00
Manuel Pégourié-Gonnard
8abd0a0c84 Merge branch 'mbedtls-2.16' into baremetal-2.16-20190909
* mbedtls-2.16: (28 commits)
  Bump version to Mbed TLS 2.16.3
  Changelog entry
  Check for zero length and NULL buffer pointer
  ssl-opt.sh: wait for proxy to start before running the script further
  Fix uninitialized variable in x509_crt
  HMAC DRBG: Split entropy-gathering requests to reduce request sizes
  Fix the license header of hkdf
  Add a change log entry
  Add a test for mlaformed ECJPAKE context
  Fix handling of md failure
  Add a test for signing content with a long ECDSA key
  Add documentation notes about the required size of the signature buffers
  Add missing MBEDTLS_ECP_C dependencies in check_config.h
  Change size of preallocated buffer for pk_sign() calls
  Adapt ChangeLog
  Fix mpi_bigendian_to_host() on bigendian systems
  Add ChangeLog entry for new function
  Add ChangeLog entry
  Correct deterministic ECDSA behavior
  Add warning for alternative ECDSA implementations
  ...
2019-09-10 11:27:14 +02:00
Hanno Becker
14b0a68083 x509_crt.c: Indicate guarding condition in #else branch 2019-09-09 09:55:31 +01:00
Hanno Becker
8d6d320603 Re-implement verify chain if vrfy cbs are disabled
This commit re-implements the previously introduced internal
verification chain API in the case where verification callbacks
are disabled. In this situation, it is not necessary to maintain
the list of individual certificates and flags comprising the
verification chain - instead, it suffices to just keep track
of the length and the total (=merged) flags.
2019-09-09 09:55:31 +01:00
Hanno Becker
adc282a5e8 Add zero-cost abstraction layer for CRT verification chain
When verifying an X.509 certificate, the current verification logic
maintains an instance of the internal mbedtls_x509_crt_verify_chain
structure representing the state of the verification process. This
instance references the list of certificates that comprise the chain
built so far together with their verification flags. This information
must be stored during verification because it's being passed to the
verification callback at the end of verification - if the user has
specified those.

If the user hasn't specified a verification callback, it is not
necessary to maintain the list of CRTs, and it is also not necessary
to maintain verification flags for each CRT individually, as they're
merged at the end of the verification process.

To allow a readable simplification of the code in case no verification
callbacks are used, this commit introduces a zero-cost abstraction layer
for the functionality that's required from the verification chain structure:
- init/reset
- add a new CRT to the chain
- get pointer to current CRT flags
- add flags to EE certificate
- get current chain length
- trigger callbacks and get final (merged) flags
This gives flexibility for re-implementing the verification chain
structure, e.g. in the case where no verification callbacks are
provided, and there's hence no need to store CRTs and flags
individually. This will be done in a later commit.
2019-09-09 09:55:31 +01:00
Hanno Becker
9ec3fe0d43 Introduce configuration option to remove CRT verification callbacks 2019-09-09 09:55:31 +01:00
Hanno Becker
a5cedbcd3f Introduce MD handle type
As has been previously done for ciphersuites, this commit introduces
a zero-cost abstraction layer around the type

  mbedtls_md_info const *

whose valid values represent implementations of message digest algorithms.

Access to a particular digest implementation can be requested by name or
digest ID through the API mbedtls_md_info_from_xxx(), which either returns
a valid implementation or NULL, representing failure.

This commit replaces such uses of `mbedtls_md_info const *` by an abstract
type `mbedtls_md_handle_t` whose valid values represent digest implementations,
and which has a designated invalid value MBEDTLS_MD_INVALID_HANDLE.

The purpose of this abstraction layer is to pave the way for builds which
support precisely one digest algorithm. In this case, mbedtls_md_handle_t
can be implemented as a two-valued type, with one value representing the
invalid handle, and the unique valid value representing the unique enabled
digest.
2019-09-09 09:45:57 +01:00
Simon Butcher
d82db9d48c Merge remote-tracking branch 'origin/pr/649' into baremetal 2019-09-07 12:46:12 +01:00
Teppo Järvelin
f69e641e03 Changed x509_internal.h methods as static.
Moved some functions under defined to get rid of compiler warnings.
Functions moved under defines:
 - mbedtls_x509_get_alg
 - mbedtls_x509_get_alg_null
 - mbedtls_x509_get_time
 - mbedtls_x509_get_ext
 - mbedtls_x509_sig_alg_gets
 - mbedtls_x509_key_size_helper

Left one function (mbedtls_x509_write_names) as non static as it increased code size.
2019-09-06 10:03:36 +03:00
Teppo Järvelin
c3e5716aaf Some minor struct optimizations. 2019-09-06 07:58:36 +03:00
Hanno Becker
59e7b08b8a TinyCrypt X.509: Adapt profiles to use TinyCrypt curve identifier 2019-09-04 16:17:45 +01:00
Hanno Becker
d931ad2aca Implement x509_profile_check_key() for TinyCrypt-based PK context 2019-09-04 16:17:45 +01:00
Teppo Järvelin
ffaba55e5d Changed x509.c to be one single compilation unit for all x509 files. 2019-09-03 16:29:41 +03:00
Andy Gross
3fc6f9d16d Fix uninitialized variable in x509_crt
This patch fixes an issue we encountered with more stringent compiler
warnings.  The signature_is_good variable has a possibility of being
used uninitialized.  This patch moves the use of the variable to a
place where it cannot be used while uninitialized.

Signed-off-by: Andy Gross <andy.gross@linaro.org>
2019-08-30 14:46:03 +03:00
Teppo Järvelin
4009d8f377 Make function mbedtls_ssl_set_hostname(...) as optional
Now function mbedtls_ssl_set_hostname is compile-time configurable
in config.h with define MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION.
This affects to many x509 API's. See config.h for details.
2019-08-27 10:47:08 +03:00
Manuel Pégourié-Gonnard
f1358acdc7 Fix bug in MBEDTLS_X509_CRT_REMOVE_TIME
When looking for a parent, all candidates were considered time-invalid due to
the #ifdef incorrectly including the `parent_valid = 1` line.

When MBEDTLS_HAVE_TIME_DATE is unset the time-validity of certificates is
never checked and always treated as valid. This is usually achieved by proper
usage of mbedtls_x509_time_is_past() and mbedtls_x509_time_is_future() (and
their definition when we don't HAVE_TIME_DATE).

Here the calls to these functions needs to be guarded by
MBEDTLS_X509_CRT_REMOVE_TIME as they access struct members whose presence is
controlled by this option. But the "valid" branch should still always be taken.

(Note: MBEDTLS_X509_CRT_REMOVE_TIME being set forces MBEDTLS_HAVE_TIME_DATE to
be unset, as enforce by check_config.h.)

This bug was found by `all.sh test_baremetal` - no need for a new test.
2019-07-30 16:56:58 +02:00
Manuel Pégourié-Gonnard
0d1db20490 Fix bug in skip_date() (MBEDTLS_X509_CRT_REMOVE_TIME)
Asserting `*p == end` right after setting `end = *p + len` will always fail
unless `len == 0`, which is never the case with properly-formed certificates.

The function x509_skip_dates() is modelled after x509_get_dates() which between
setting `end` and comparing it to `*p` calls mbedtls_x509_get_time() which
advances `*p` to the expected value, which is why this test works in
get_dates().

Since `skip_dates()` has `skip`, not `validate` in its name, and the entire
point of `MBEDTLS_X509_CRT_REMOVE_TIME` is to save code, we don't want to
call the relatively large functions needed to properly parse (and validate)
dates before throwing the parsed dates away, we can just fast-forward to the
end of the sequence.

This makes updating `end` and comparing it to `*p` after the fast-forward
redundant, as the comparison will always be true (unlike the case where we
actually parse the contents of the sequence).

This bug was found by `all.sh test_baremetal` - no need for a new test.
2019-07-30 16:56:25 +02:00
Hanno Becker
d07614c529 Introduce MBEDTLS_X509_CRT_REMOVE_SUBJECT_ISSUER_ID removing IDs 2019-07-04 14:04:03 +01:00
Hanno Becker
843b71a1df Introduce MBEDTLS_X509_CRT_REMOVE_TIME removing time fields from CRT 2019-07-04 14:04:03 +01:00
Hanno Becker
6f61b7bb5c Remove 'CRT fallback' during X.509 CRT verification if !TIME_DATE 2019-07-04 14:03:26 +01:00
Manuel Pégourié-Gonnard
de8869c529 Merge remote-tracking branch 'restricted/pr/608' into baremetal-proposed
* restricted/pr/608:
  programs: Make `make clean` clean all programs always
  ssl_tls: Enable Suite B with subset of ECP curves
  windows: Fix Release x64 configuration
  timing: Remove redundant include file
  net_sockets: Fix typo in net_would_block()
  Add all.sh component that exercises invalid_param checks
  Remove mbedtls_param_failed from programs
  Make it easier to define MBEDTLS_PARAM_FAILED as assert
  Make test suites compatible with #include <assert.h>
  Pass -m32 to the linker as well
  Update library to 2.16.2
  Use 'config.pl baremetal' in all.sh
  Clarify ChangeLog entry for fix to #1628
  Fix #2370, minor typos and spelling mistakes
  Add Changelog entry for clang test-ref-configs.pl fix
  Enable more compiler warnings in tests/Makefile
  Change file scoping of test helpers.function
2019-07-03 10:31:46 +02:00
Hanno Becker
3aa121660e Add comment about X.509 name comparison of buffer with itself 2019-07-02 16:47:40 +01:00
Hanno Becker
410322f23e Fix guard controlling whether nested acquire calls are allowed
Resource counting as a safe-guard against nested acquire calls
is implemented if and only if MBEDTLS_X509_ALWAYS_FLUSH is disabled
_or_ MBEDTLS_THREADING_C is enabled.
2019-07-02 13:37:12 +01:00
Hanno Becker
abd929c89c Merge branch 'mbedtls-2.16' into baremetal-2.16-01_07_19 2019-07-01 11:25:42 +01:00
Hanno Becker
fc99a09cc4 Don't allow nested CRT acquire()-calls if MBEDTLS_X509_ALWAYS_FLUSH
Forbidding nested calls to acquire() allows to remove the reference
counting logic and hence saving some bytes of code. This is valuable
because MBEDTLS_X509_ALWAYS_FLUSH is likely to be used on constrained
systems where code-size is limited.
2019-06-28 14:48:32 +01:00
Hanno Becker
a4bfaa8204 Make X.509 CRT cache reference counting unconditional
Previously, reference counting for the CRT frames and PK contexts
handed out by mbedtls_x509_crt_{frame|pk}_acquire() was implemented
only in case threading support was enabled, which leaves the door
open for a potential use-after-free should a single-threaded application
use nested calls to mbedtls_x509_crt_acquire().

Since Mbed TLS itself does not use such nested calls, it might be
preferred long-term to forbid nesting of acquire calls on the API
level, and hence get rid of reference counting in the interest of
code-size benefits. However, this can be considered as an optimization
of X.509 on demand parsing, and for now this commit introduces
reference counting unconditionally to have a safe version of
on demand parsing to build further optimizations upon.
2019-06-28 14:48:32 +01:00
Hanno Becker
ed05888195 x509_crt.c: Add blank line to increase readability 2019-06-28 14:48:31 +01:00
Hanno Becker
08d341211d Move signature-info extraction out of MBEDTLS_X509_REMOVE_INFO
During rebase, the definition of ::mbedtls_x509_crt_sig_info
as well as x509_crt_free_sig_info() and x509_crt_get_sig_info()
were accidentally guarded by !MBEDTLS_X509_REMOVE_INFO.

This commit moves their definition outside of that guard.
2019-06-25 10:41:31 +01:00
Hanno Becker
040c564888 Fix certificate validity checking logic to work with !TIME_DATE
If MBEDTLS_HAVE_TIME_DATE is undefined, the functions
`mbedtls_x509_time_is_past()` and `mbedtls_x509_time_is_future()`
are still defined but return `0` (that is, no time is seen to in
the past or future). To maintain functional correctness, this
means that these functions have to be called in a way where
the condition being checked for is the erroneous one: Concretely,
one shouldn't check that a CRT's `validFrom` is in the past,
or that its `validTo` is in the future, because that would
fail if !MBEDTLS_HAVE_TIME_DATE. Instead, one should check
that `validFrom` is NOT in the future, and `validTo` is NOT
in the past. That was the logic previously, but an uncautious
change during transition to X.509 on-demand parsing has
changed it. This commit fixes this.
2019-06-25 09:11:11 +01:00