Commit Graph

16474 Commits

Author SHA1 Message Date
Gilles Peskine
c0656b43f1 Note the reordered fields in SSL structures
This is technically an API break according to the unwritten rules of API
compatibility for Mbed TLS 2.x. However, it is very unlikely to affect any
realistic application, with the possible exception of applications that
define a global constant of type mbedtls_ssl_config.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2021-11-16 19:00:04 +01:00
Gilles Peskine
7f03d9ecc6 mbedtls_ssl_config: Replace bit-fields by separate bytes
This slightly increases the RAM consumption per context, but saves code
size on architectures with an instruction for direct byte access (which is
most of them).

Although this is technically an API break, in practice, a realistic
application won't break: it would have had to bypass API functions and rely
on the field size (e.g. relying on -1 == 1 in a 1-bit field).

Results (arm-none-eabi-gcc 7.3.1, build_arm_none_eabi_gcc_m0plus build):
library/ssl_cli.o: 19952 -> 19900 (diff: 52)
library/ssl_msg.o: 25810 -> 25798 (diff: 12)
library/ssl_srv.o: 22371 -> 22299 (diff: 72)
library/ssl_tls.o: 23274 -> 23038 (diff: 236)

Results (same architecture, config-suite-b.h + MBEDTLS_ECDH_LEGACY_CONTEXT +
MBEDTLS_ECP_RESTARTABLE):
library/ssl_cli.o: 2868 -> 2848 (diff: 20)
library/ssl_msg.o: 2916 -> 2924 (diff: -8)
library/ssl_srv.o: 3204 -> 3184 (diff: 20)
library/ssl_tls.o: 5860 -> 5756 (diff: 104)

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2021-11-16 18:56:49 +01:00
Lukasz Gniadzik
9a0e0affef mbedtls_ssl_config, mbedtls_ssl_session: reorder fields
Move small fields first so that more fields can be within the Arm Thumb
128-element direct access window.

The ordering in this commit is not based on field access frequency.

Results (arm-none-eabi-gcc 7.3.1, build_arm_none_eabi_gcc_m0plus build):
library/ssl_cli.o: 20104 -> 19952 (diff: 152)
library/ssl_msg.o: 25942 -> 25810 (diff: 132)
library/ssl_srv.o: 22467 -> 22371 (diff: 96)
library/ssl_tls.o: 23390 -> 23274 (diff: 116)

Results (same architecture, config-suite-b.h + MBEDTLS_ECDH_LEGACY_CONTEXT +
MBEDTLS_ECP_RESTARTABLE):
library/ssl_cli.o: 2928 -> 2868 (diff: 60)
library/ssl_msg.o: 2924 -> 2916 (diff: 8)
library/ssl_srv.o: 3232 -> 3204 (diff: 28)
library/ssl_tls.o: 5904 -> 5860 (diff: 44)

Signed-off-by: Lukasz Gniadzik <lukasz.gniadzik@mobica.com>
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2021-11-16 18:05:27 +01:00
Gilles Peskine
baccfef741 mbedtls_ssl_handshake_params: reorder fields to save code size
Reorder fields mbedtls_ssl_handshake_params in order to save code on Arm
Thumb builds. The general idea is to put often-used fields in the direct
access window of 128 elements from the beginning of the structure.

The reordering is a human selection based on a report of field offset and
use counts, and informed by measuring the code size with various
arrangements. Some notes:
* I moved most byte-sized fields at the beginning where they're sure to be
  in the direct access window.
* I moved buffering earlier because it can be around the threshold depending
  on the configuration, and it's accessed in a lot of places.
* I moved several fields, including update_checksum and friends, early so
  that they're guaranteed to be in the early access window.
* I tried moving randbytes or premaster to the early access window, but
  I couldn't find a placement which would save code size, presumably because
  they're bumping too many other fields, and they're mostly accessed through
  memcpy and friends which translates to instructions that don't have an
  offset for free anyway.

Results (arm-none-eabi-gcc 7.3.1, build_arm_none_eabi_gcc_m0plus build):
library/ssl_cli.o: 20200 -> 20104 (diff: 96)
library/ssl_msg.o: 25978 -> 25942 (diff: 36)
library/ssl_srv.o: 22691 -> 22467 (diff: 224)
library/ssl_tls.o: 23570 -> 23390 (diff: 180)

Results (same architecture, config-suite-b.h + MBEDTLS_ECDH_LEGACY_CONTEXT +
MBEDTLS_ECP_RESTARTABLE):
library/ssl_cli.o: 3012 -> 2928 (diff: 84)
library/ssl_msg.o: 2932 -> 2924 (diff: 8)
library/ssl_srv.o: 3288 -> 3232 (diff: 56)
library/ssl_tls.o: 6032 -> 5904 (diff: 128)

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2021-11-16 17:44:31 +01:00
Gilles Peskine
51070849fa mbedtls_ssl_handshake_params: use bytes for some small values
Replace bitfields mbedtls_ssl_handshake_params by bytes. This saves some
code size, and since the bitfields weren't group, this doesn't increase the
RAM usage.

Replace several ints that only store values in the range 0..255 by uint8_t.
This can increase or decrease the code size depending on the architecture
and on how the field is used. I chose changes that save code size on Arm
Thumb builds and may potentially save more after field reordering.

Leave the bitfields in struct mbedtls_ssl_hs_buffer alone: replacing them by
uint8_t slightly increases the code size.

Results (arm-none-eabi-gcc 7.3.1, build_arm_none_eabi_gcc_m0plus build):
library/ssl_srv.o: 22735 -> 22691 (diff: 44)
library/ssl_tls.o: 23566 -> 23570 (diff: -4)

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2021-11-16 16:44:00 +01:00
Gilles Peskine
4a13ebff39 Tweak whitespace for readability
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2021-11-16 15:21:44 +01:00
Gilles Peskine
b8006a66f2 PSA global data: move fields around to save code size
Move fields around to have fewer accesses outside the 128-element Thumb
direct access window.

In psa_crypto.c's global_data, put the state fields first (-20).

In psa_crypto_slot_management.c's global_data, keep the key slots first
(otherwise it's +24).

In mbedtls_psa_random_context_t, swapping entropy and drbg makes no
difference (at least when the DRBG is mbedtls_ctr_drbg_context).

Results (arm-none-eabi-gcc 7.3.1, build_arm_none_eabi_gcc_m0plus build):
library/psa_crypto.o: 16166 -> 16146 (diff: 20)

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2021-11-16 15:00:45 +01:00
Gilles Peskine
f5d7eef11f PSA operation structures: move less-used fields to the end
Move fields around to have fewer accesses outside the 128-element Thumb
direct access window.

In psa_hkdf_key_derivation_t, move the large fields (output_block, prk,
hmac) after the state bit-fields. Experimentally, it's slightly better
to put hmac last.

In aead_operation_t, tag_length was outside the window. The details depend
on the sizes of contexts included in ctx. Make the large ctx be the last
field.

In mbedtls_psa_hmac_operation_t, the opad field is outside the window when
SHA-512 is enabled. Moving opad before hash_ctx only saves 4 bytes and made
the structure clumsy, so I left it alone.

Results (arm-none-eabi-gcc 7.3.1, build_arm_none_eabi_gcc_m0plus build):
library/psa_crypto.o: 16246 -> 16166 (diff: 80)
library/psa_crypto_aead.o: 952 -> 928 (diff: 24)

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2021-11-16 15:00:17 +01:00
Gabor Mezei
2dcccbfc19
Fix function name in debug message
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-16 13:34:05 +01:00
Tom Cosgrove
58efe6184e Fix builds when config.h only defines MBEDTLS_BIGNUM_C
Fixes #4929

Signed-off-by: Tom Cosgrove <tom.cosgrove@arm.com>
2021-11-15 09:59:53 +00:00
Przemyslaw Stekiel
a226ac9738 ssl_client2/ssl_server2: Rework ordering of cleanup
Signed-off-by: Przemyslaw Stekiel <przemyslaw.stekiel@mobica.com>
2021-11-14 20:03:24 +01:00
Przemyslaw Stekiel
e9dea7c3b0 ssl_client2: move memory leak check before rng_free()
Signed-off-by: Przemyslaw Stekiel <przemyslaw.stekiel@mobica.com>
2021-11-14 20:03:24 +01:00
Przemyslaw Stekiel
b66bc0ad4a Move psa_crypto_slot_management.h out from psa_crypto_helpers.h
Signed-off-by: Przemyslaw Stekiel <przemyslaw.stekiel@mobica.com>
2021-11-14 20:03:23 +01:00
Przemyslaw Stekiel
d6e0a5824a ssl_client2/ssl_server2: Move is_psa_leaking() before mbedtls_psa_crypto_free() (and rng_free())
Signed-off-by: Przemyslaw Stekiel <przemyslaw.stekiel@mobica.com>
2021-11-14 20:03:23 +01:00
Przemyslaw Stekiel
7c7fb877c6 ssl_client2, ssl_server2: add check for psa memory leaks
Signed-off-by: Przemyslaw Stekiel <przemyslaw.stekiel@mobica.com>
2021-11-14 20:03:23 +01:00
Bence Szépkúti
c1e79fd2e3 Enable CMAC for PSA crypto compliance tests
Signed-off-by: Bence Szépkúti <bence.szepkuti@arm.com>
2021-11-11 20:47:32 +01:00
Bence Szépkúti
24ec529f82 Multipart AEAD is not supported in Mbed TLS 2.x
Signed-off-by: Bence Szépkúti <bence.szepkuti@arm.com>
2021-11-11 20:47:29 +01:00
Bence Szépkúti
e30fcb6ed5 Remove superfluous expected failures from list
Issue #5144 doesn't affect development_2.x

Signed-off-by: Bence Szépkúti <bence.szepkuti@arm.com>
2021-11-11 16:24:19 +01:00
Gabor Mezei
b9e1f2a3cf
Update generated files
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 15:42:41 +01:00
Gabor Mezei
84d739846c
Update changelog with the new public API
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:33:19 +01:00
Gabor Mezei
dbe0f892b3
Fix documentation and comments
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:33:19 +01:00
Gabor Mezei
c0ae1cf45a
Rename internal header constant_time.h to constant_time_internal.h
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:33:19 +01:00
Gabor Mezei
18a44949d0
Rename constant-time functions to have mbedtls_ct prefix
Rename functions to better suite with the module name.

Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:32:01 +01:00
Gabor Mezei
f127a0e2b1
Remove unneeded include
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:54 +01:00
Gabor Mezei
da20651b73
Fix documentation
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:54 +01:00
Gabor Mezei
61bf64fbd0
Bind functions' availability for config options
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:54 +01:00
Gabor Mezei
e24dea8225
Move mbedtls_cf_memcmp to a new public header
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:54 +01:00
Gabor Mezei
6e0e990544
Add macro guard for header file
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:53 +01:00
Gabor Mezei
2b35880d41
Bind functions' availability for config options
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:53 +01:00
Gabor Mezei
4e2de62fef
Remove unused function
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:53 +01:00
Gabor Mezei
fd8a42d914
Make functions static
These functions are only used as an auxiliary function for constant-time functions.

Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:53 +01:00
Gabor Mezei
4b4e4d8880
Update documentation and comments
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:53 +01:00
Gabor Mezei
91deea7765
Rename and reorder function parameters
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:53 +01:00
Gabor Mezei
150bdee126
Use condition for not sensitive data
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:53 +01:00
Gabor Mezei
3c38b6e9e1
Move implementation specific comment
This comment is about how the functions are implemented, not about their
public interface, so it doesn't belong in the header file.
It applies to everything in constant_time.c so moved there.

Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:52 +01:00
Gabor Mezei
2c5ed2244b
Make mbedtls_cf_size_mask_lt function static
The mbedtls_cf_size_mask_lt is solely used as an auxiliary function
for mbedtls_cf_size_mask_ge.

Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:52 +01:00
gabor-mezei-arm
d5a392aa2c
Fix missing includes
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:52 +01:00
gabor-mezei-arm
10117d673e
Add changelog entry
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:52 +01:00
gabor-mezei-arm
7e6a1eaf8f
Add documentation for the functions
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:52 +01:00
gabor-mezei-arm
1ffd0ccf02
Unify equality checker functions return value
The equality checker functions always return 0 or 1 value,
thus the type of return value can be the same dispite of the
size of the parameters.

Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:52 +01:00
gabor-mezei-arm
60febd5d8a
Propagate usage of mask generation functions
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:52 +01:00
gabor-mezei-arm
2f2c0bead3
Unify mask generation functions
Generate all-bits 0 or all bits 1 mask from a value instead of from a bit.

Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:51 +01:00
gabor-mezei-arm
5e4882498e
Unify function parameters
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:51 +01:00
gabor-mezei-arm
378e7eb5cc
Unify memcmp functions
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:51 +01:00
gabor-mezei-arm
04087dffcd
Typo: Unify indentation of function parameters
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:51 +01:00
gabor-mezei-arm
f52941ef73
Move mbedtls_cf_rsaes_pkcs1_v15_unpadding function to the constant-time module
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:51 +01:00
gabor-mezei-arm
c2aee6fc0b
Move the constant-time part of mbedtls_rsa_rsaes_pkcs1_v15_decrypt to a function
Tne unpadding part of `mbedtls_rsa_rsaes_pkcs1_v15_decrypt` function is
contant-time therefore it moved to a separate function to be prepared
for moving to the contant-time module.

Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:04:51 +01:00
gabor-mezei-arm
bc3a288b2c
Create mbedtls_cf_size_if function
Add a constant-time function with size_t parameter for choosing
between two integer values, like the ?: ternary operator.

Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:03:04 +01:00
gabor-mezei-arm
b10301d2fc
Move mbedtls_mpi_lt_mpi_ct function to the constant-time module
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:02:38 +01:00
gabor-mezei-arm
58fc8a65ab Move mbedtls_mpi_safe_cond_swap function to the constant-time module
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
2021-11-11 11:01:08 +01:00