Commit Graph

5912 Commits

Author SHA1 Message Date
Manuel Pégourié-Gonnard
7fe2c5f086 Add mbedtls_ssl_cf_memcpy_offset() with tests
The tests are supposed to be failing now (in all.sh component
test_memsan_constant_flow), but they don't as apparently MemSan doesn't
complain when the src argument of memcpy() is uninitialized, see
https://github.com/google/sanitizers/issues/1296

The next commit will add an option to test constant flow with valgrind, which
will hopefully correctly flag the current non-constant-flow implementation.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-08-19 11:56:02 +02:00
Manuel Pégourié-Gonnard
3c31afaca6 Use temporary buffer to hold the peer's HMAC
This paves the way for a constant-flow implementation of HMAC checking, by
making sure that the comparison happens at a constant address. The missing
step is obviously to copy the HMAC from the secret offset to this temporary
buffer with constant flow, which will be done in the next few commits.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-08-19 11:56:01 +02:00
Gilles Peskine
71f4fa13bb
Merge pull request #721 from gilles-peskine-arm/x509parse_crl-empty_entry-development
Fix buffer overflow in x509_get_entries (oss-fuzz 24123)
2020-08-14 23:22:31 +02:00
Manuel Pégourié-Gonnard
c4af324a4b Merge branch 'development' into development-restricted
* development: (55 commits)
  Log change as bugfix
  Add changelog entry
  Clarify updates to the persistent state in storage
  With multiple applicable transparent drivers, the order is unspecified
  Minor clarifications
  Give some examples of purpsoses of pure-software transparent driver
  Fix typos
  Add a link to the PSA API specification
  Explain locations vs lifetimes
  Initialize key pointer in ecdh to NULL
  Add buffer zeroization when ecp_write_key fails
  Simplified key slot deletion
  Style fixes
  Use arc4random_buf instead of rand on NetBSD
  Apply review feedback
  Update open question section about public key storage
  Remove the paragraph about declaring application needs
  Change driver persistent data to a callback interface
  Rework and expand key management in opaque drivers
  Fix typos and copypasta
  ...
2020-08-14 10:11:21 +02:00
Gilles Peskine
3890f7cd3d
Merge pull request #3540 from gufe44/netbsd-rand-arc4random_buf
Use arc4random_buf instead of rand on NetBSD
2020-08-13 15:27:45 +02:00
Gilles Peskine
e900b59703
Merge pull request #719 from gabor-mezei-arm/689_zeroising_of_plaintext_buffers
Zeroising of plaintext buffers in mbedtls_ssl_read()
2020-08-12 18:51:42 +02:00
Manuel Pégourié-Gonnard
eaa0739143
Merge pull request #716 from mpg/ct-varlen-hmac
Add constant-flow variable-length HMAC function
2020-08-10 12:40:33 +02:00
Gilles Peskine
67a85d1d3b
Merge pull request #3492 from stevew817/rework/key_slot_contains_key_buffer
Rework PSA Crypto core to store keys in export representation
2020-08-05 21:16:11 +02:00
Steven Cooreman
d4867877f1 Initialize key pointer in ecdh to NULL
Since it is being dereferenced by free on exit it should be inited to NULL.
Also added a small test that would trigger the issue.

Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-08-05 17:38:47 +02:00
Steven Cooreman
b7f6deaae7 Add buffer zeroization when ecp_write_key fails
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-08-05 17:38:47 +02:00
Steven Cooreman
fd4d69a72e Simplified key slot deletion
And zeroize key buffer before freeing to avoid keys hanging around on the
heap.

Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-08-05 17:38:32 +02:00
Steven Cooreman
291498600b Style fixes
* return is treated as a function call
* space between opening and closing parentheses
* remove whiteline between assignment and checking of same variable

Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-08-05 16:44:24 +02:00
gufe44
c2620dac02 Use arc4random_buf instead of rand on NetBSD
Avoid old implementation of rand returning numbers with cyclical lower bits. Allow tests to pass.

Signed-off-by: gufe44 <gu981@protonmail.com>
2020-08-03 17:56:50 +02:00
Steven Cooreman
4fed455347 Apply review feedback
* No need to check for NULL before free'ing
* No need to reset variables that weren't touched
* Set output buffer to zero if key output fails
* Document internal functions and rearrange order of input arguments to
  better match other functions.
* Clean up Montgomery fix to be less verbose code

Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-08-03 14:46:12 +02:00
Steven Cooreman
3fa684ed91 Allow importing Montgomery public keys in PSA Crypto
PSA Crypto was checking the byte length of a to-be-imported public ECP key
against the expected length for Weierstrass keys, forgetting that
Curve25519/Curve448 exists.

Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-07-30 15:35:14 +02:00
Steven Cooreman
7f39187d6b Convert load_xxx_representation to take buffers instead of a whole slot
Avoids stack-allocating a key slot during ECDH, and mock-attaching a
key to a key slot during key import.

Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-07-30 15:21:41 +02:00
Steven Cooreman
6d839f05bf Cleanup
* No null-check before calling free
* Close memory leak
* No need for double check of privkey validity

Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-07-30 15:21:41 +02:00
Gilles Peskine
171826550f
Merge pull request #709 from mpg/protect-base-blinding-dev-restricted
Protect base blinding in RSA and DHM
2020-07-29 10:58:53 +02:00
Steven Cooreman
a2371e53e4 Update after feedback from #3492
* Allocate internal representation contexts on the heap (i.e. don't change
  where they're being allocated)
* Unify load_xxx_representation in terms of allocation and init behaviour

Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-07-28 14:30:39 +02:00
Steven Cooreman
75b743666e Update after feedback on #3492
* Updated wording
* Split out buffer allocation to a convenience function
* Moved variable declarations to beginning of their code block

Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-07-28 14:30:13 +02:00
Manuel Pégourié-Gonnard
f009542747 Add missing const for consistency
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-27 09:34:10 +02:00
Manuel Pégourié-Gonnard
e747843903 Fix a whitespace issue
Co-authored-by: Janos Follath <janos.follath@arm.com>
2020-07-27 09:34:10 +02:00
Manuel Pégourié-Gonnard
390fb4ff34 Fix typos in comments
Co-authored-by: Janos Follath <janos.follath@arm.com>
2020-07-27 09:34:10 +02:00
Manuel Pégourié-Gonnard
e0765f35d5 Use int ret = MBEDTLS_ERROR_CORRUPTION_DETECTED; idiom
Co-authored-by: Gilles Peskine <gilles.peskine@arm.com>
2020-07-27 09:34:10 +02:00
Steven Cooreman
19fd574b3a Disconnect knowing about a PSA key type from knowing the mbedTLS API
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-07-24 23:46:21 +02:00
Steven Cooreman
560c28a1ac Unify key handling logic
Now that both ECP and RSA keys are represented in export representation,
they can be treated more uniformly.

Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-07-24 23:44:31 +02:00
Steven Cooreman
acda8346bf Remove ECP internal representation from key slot
Change to on-demand loading of the internal representation when required
in order to call an mbed TLS cryptography API.

Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-07-24 23:44:31 +02:00
Steven Cooreman
a01795d609 Remove RSA internal representation from key slot
Change to on-demand loading of the internal representation when required
in order to call an mbed TLS cryptography API.

Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-07-24 23:44:31 +02:00
Steven Cooreman
81be2fa0b2 Pull apart slot memory allocation from key validation.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-07-24 23:44:31 +02:00
Steven Cooreman
71fd80d279 Re-define members of psa_key_slot_t
In preparation for the implementation of the accelerator APIs. This is
ramping up to the goal of only storing the export representation in the
key slot, and not keeping the crypto implementation-specific representations
around.

Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
2020-07-24 23:44:25 +02:00
Manuel Pégourié-Gonnard
44c9fdde6e Check errors from the MD layer
Could be out-of-memory for some functions, accelerator issues for others.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-22 11:31:20 +02:00
Manuel Pégourié-Gonnard
9713e13e68 Remove unnecessary cast
This is C, not C++, casts between void * and other pointer types are free.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-22 11:31:19 +02:00
Manuel Pégourié-Gonnard
baccf803ad Improve some comments and internal documentation
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-22 11:31:19 +02:00
Manuel Pégourié-Gonnard
ed0e86428d Factor repeated condition to its own macro
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-22 11:31:19 +02:00
Manuel Pégourié-Gonnard
7a8b1e6b71 Implement cf_hmac() actually with constant flow
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-22 11:31:18 +02:00
Gilles Peskine
6d9c8d7b2d Minor documentation improvements
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2020-07-22 03:17:25 +02:00
Gilles Peskine
5997005611 Fix unused variables in Montgomery-only configuration
Signed-off-by: Gilles Peskine <gilles.peskine@arm.com>
2020-07-22 03:17:24 +02:00
Gilles Peskine
a088c81fcb Adjust ECP self-test to support Curve448
Adjust the Montgomery self-test to use Curve448 in builds without
Curve25519.

Signed-off-by: Gilles Peskine <gilles.peskine@arm.com>
2020-07-22 03:17:24 +02:00
Gilles Peskine
24666795e4 ECP self test: add self-test step for Montgomery curves
Run some self-test both for a short Weierstrass curve and for a
Montgomery curve, if the build-time configuration includes a curve of
both types. Run both because there are significant differences in the
implementation.

The test data is suitable for Curve25519.

Signed-off-by: Gilles Peskine <gilles.peskine@arm.com>
2020-07-22 03:17:24 +02:00
Gilles Peskine
c95696fec4 Factor common code in mbedtls_ecp_self_test
No intended behavior change.

Signed-off-by: Gilles Peskine <gilles.peskine@arm.com>
2020-07-22 03:17:24 +02:00
Gilles Peskine
d9767a5799 Tweak ECP self-test to work with secp192k1
The constants used in the test worked with every supported curve
except secp192k1. For secp192k1, the "N-1" exponent was too large.

Signed-off-by: Gilles Peskine <gilles.peskine@arm.com>
2020-07-22 03:17:24 +02:00
Gilles Peskine
aa9493a411 Add guards around code that is specific to dynamically-loaded groups
For some curves (semi-coincidentally, short Weierstrass curves), the
ECP module calculates some group parameters dynamically. Build the
code to calculate the parameters only if a relevant curve is enabled.
This fixes an unused function warning when building with only
Montgomery curves.

Signed-off-by: Gilles Peskine <gilles.peskine@arm.com>
2020-07-22 03:17:23 +02:00
Gilles Peskine
e8c04fed51 Replace ECP_xxx by MBEDTLS_ECP__xxx_ENABLED
Replace the now-redundant internal curve type macros ECP_xxx by the
macros MBEDTLS_ECP__xxx_ENABLED which are declared in ecp.h.

Signed-off-by: Gilles Peskine <gilles.peskine@arm.com>
2020-07-22 03:17:22 +02:00
Gilles Peskine
9b99a8942f mbedtls_ecp_muladd is only for short Weierstrass curves
Document that mbedtls_ecp_muladd and mbedtls_ecp_muladd_restartable
are only implemented on short Weierstrass curves.

Exclude these functions at build time if no short Weierstrass curve
is included in the build. Before, these functions failed to compile in
such a configuration.

Signed-off-by: Gilles Peskine <gilles.peskine@arm.com>
2020-07-22 02:48:31 +02:00
Gilles Peskine
5dd5a491da x509_crl_parse: fix 1-byte buffer overflow and entry->raw.tag
In the entries (mbedtls_x509_crl_entry values) on the list constructed
by mbedtls_x509_crl_parse_der(), set entry->raw.tag to
(SEQUENCE | CONSTRUCTED) rather than to the tag of the first ASN.1
element of the entry (which happens to be the tag of the serial
number, so INTEGER or INTEGER | CONTEXT_SPECIFIC). This is doesn't
really matter in practice (and in particular the value is never used
in Mbed TLS itself), and isn't documented, but at least it's
consistent with how mbedtls_x509_buf is normally used.

The primary importance of this change is that the old code tried to
access the tag of the first element of the entry even when the entry
happened to be empty. If the entry was empty and not followed by
anything else in the CRL, this could cause a read 1 byte after the end
of the buffer containing the CRL.

The test case "X509 CRL ASN1 (TBSCertList, single empty entry at end)"
hit the problematic buffer overflow, which is detected with ASan.

Credit to OSS-Fuzz for detecting the problem.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2020-07-16 18:40:17 +02:00
Manuel Pégourié-Gonnard
7868396e78 Clarify some comments
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-16 10:24:34 +02:00
Manuel Pégourié-Gonnard
e288ec0651 Fix memory leak on error path
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-16 09:23:30 +02:00
gabor-mezei-arm
a321413807
Zeroising of plaintext buffers to erase unused application data from memory
Signed-off-by: gabor-mezei-arm <gabor.mezei@arm.com>
2020-07-15 14:14:41 +02:00
Manuel Pégourié-Gonnard
6240defd17 Add MBEDTLS_TEST_CONSTANT_FLOW_MEMSAN
This option allows to test the constant-flow nature of selected code, using
MemSan and the fundamental observation behind ctgrind that the set of
operations allowed on undefined memory by dynamic analysers is the same as the
set of operations allowed on secret data to avoid leaking it to a local
attacker via side channels, namely, any operation except branching and
dereferencing.

(This isn't the full story, as on some CPUs some instructions have variable
execution depending on the inputs, most notably division and on some cores
multiplication. However, testing that no branch or memory access depends on
secret data is already a good start.)

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-15 12:26:22 +02:00
Manuel Pégourié-Gonnard
65a6fa3e26 Make cf_hmac() STATIC_TESTABLE
The test function now depends on MBEDTLS_TEST_HOOKS, which is enabled by
config.py full, and since there are already components in all.sh exercising
the full config, this test function is sill exercised even with this new
dependency.

Since this is the first time a test function depends on MBEDTLS_TEST_HOOKS,
fix a bug in check-names.sh that wasn't apparent so far: headers from
library/*.h were not considered when looking for macro definitions. This
became apparent because MBEDTLS_STATIC_TESTABLE is defined in library/common.h
and started being used in library/ssl_msg.c, so was flagged as a likely typo.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-15 12:26:21 +02:00