Commit graph

77 commits

Author SHA1 Message Date
Joe Subbiani c54e908656 Replace instances of byte reading macros with PUT
Instances of a group of byte reading macros which are equivilant to
MBEDTLS_PUT_UINTx_yz

Signed-off-by: Joe Subbiani <joe.subbiani@arm.com>
2021-08-03 14:09:05 +01:00
Joe Subbiani ad1115a3fd Use byte reading macros in places not using a byte mask
byte shifting opertations throughout library/ were only replaced with
the byte reading macros when an 0xff mask was being used.
The byte reading macros are now more widley used, however they have not
been used in all cases of a byte shift operation, as it detracted from
the immediate readability or otherwise did not seem appropriate.

Signed-off-by: Joe Subbiani <joe.subbiani@arm.com>
2021-08-03 14:08:33 +01:00
Joe Subbiani c045dc14b0 Replace MBEDTLS_CHAR_x with MBEDTLS_BYTE_x
The CHAR macros casted to an unsigned char which in this project
is garunteed to be 8 bits - the same as uint8_t (which BYTE casts
to) therefore, instances of CHAR have been swapped with BYTE and
the number of macros have been cut down

Signed-off-by: Joe Subbiani <joe.subbiani@arm.com>
2021-08-03 14:08:06 +01:00
Joe Subbiani 6b897c930c Add Character byte reading macros
These cast to an unsigned char rather than a uint8_t
like with MBEDTLS_BYTE_x
These save alot of space and will improve maintence by
replacing the appropriate code with MBEDTLS_CHAR_x

Signed-off-by: Joe Subbiani <joe.subbiani@arm.com>
2021-08-03 14:01:51 +01:00
Joe Subbiani 2bbafda1f8 Prefixed macros with MBEDTLS
As per tests/scripts/check-names.sh, macros in
library/ header files should be prefixed with
MBEDTLS_
The macro functions in common.h where also indented
to comply with the same test

Signed-off-by: Joe Subbiani <joe.subbiani@arm.com>
2021-08-03 13:38:53 +01:00
Joe Subbiani 61f7d73336 Remove trailing whitespace
Trailing white spaces causing check_files.py to fail

Signed-off-by: Joe Subbiani <joe.subbiani@arm.com>
2021-08-03 13:19:38 +01:00
Joe Subbiani ba486b0084 Implement byte reading macros into library/
To improve readability by saving horizontal and vertical space.
Removed unecessary & 0xFF.
Byte reading macros implemented in library/common.h, All files
containing "& 0xff" were modified.
Comments/Documentation not yet added to the macro definitions.

Fixes #4274

Signed-off-by: Joe Subbiani <joe.subbiani@arm.com>
2021-08-03 13:17:40 +01:00
Manuel Pégourié-Gonnard 21bfbdd703 Fix misuse of MD API in SSL constant-flow HMAC
The sequence of calls starts-update-starts-update-finish is not a
guaranteed valid way to abort an operation and start a new one. Our
software implementation just happens to support it, but alt
implementations may very well not support it.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2021-05-19 10:40:02 +02:00
Paul Elliott d48d5c6615 Fix size_t and longlong specifiers for MinGW
MinGW and older windows compilers cannot cope with %zu or %lld (there is
a workaround for MinGW, but it involves linking more code, there is no
workaround for Windows compilers prior to 2013). Attempt to work around
this by defining printf specifiers for size_t per platform for the
compilers that cannot use the C99 specifiers.

Signed-off-by: Paul Elliott <paul.elliott@arm.com>
2021-03-10 17:00:32 +00:00
Paul Elliott 3891caf1ce Misc review requested fixes
Style fixes and cast certain defines to size_t

Signed-off-by: Paul Elliott <paul.elliott@arm.com>
2021-03-10 17:00:32 +00:00
Paul Elliott 9f35211774 Fixes for invalid printf format specifiers
Fixes for printf format specifiers, where they have been flagged as
invalid sizes by coverity, and new build flags to enable catching these
errors when building using CMake. Note that this patch uses %zu, which
requires C99 or later.

Signed-off-by: Paul Elliott <paul.elliott@arm.com>
2021-03-10 17:00:32 +00:00
Janos Follath 3aae5d4ed7
Merge pull request #781 from mpg/cipher-auth-crypt-restricted
Fix buffer overflow with NIST-KW in cipher layer
2020-12-07 12:58:36 +00:00
Manuel Pégourié-Gonnard f5cf71e14a Stop using deprecated functions in the library
all.sh -k '*deprecated*' now passes again

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-12-03 12:25:10 +01:00
Christian von Arnim 883d304785
Fix: Add missing arguments to debug message.
Signed-off-by: Christian von Arnim <christian.von-arnim@isw.uni-stuttgart.de>
2020-12-02 10:13:02 +01:00
Hanno Becker a817ea449a Check presence of DTLS timers only once
Mbed TLS requires users of DTLS to configure timer callbacks
needed to implement the wait-and-retransmit logic of DTLS.

Previously, the presence of these timer callbacks was checked
at every invocation of `mbedtls_ssl_fetch_input()`, so lowest
layer of the messaging stack interfacing with the underlying
transport.

This commit removes this recurring check and instead checks the
presence of timers once at the beginning of the handshake.

The main rationale for this change is that it is a step towards
separating the various layers of the messaging stack more cleanly:
datagram layer, record layer, message layer, retransmission layer.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-10-20 15:29:14 +01:00
Manuel Pégourié-Gonnard 6d6f8a4b97 Clarify descriptions of constant-flow helpers
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-09-28 09:51:41 +02:00
Manuel Pégourié-Gonnard 822b3729e7 Remove last use of non-bit operations
According to https://www.bearssl.org/ctmul.html even single-precision
multiplication is not constant-time on some older platforms.

An added benefit of the new code is that it removes the somewhat mysterious
constant 0x1ff - which was selected because at that point the maximum value of
padlen was 256. The new code is perhaps a bit more readable for that reason.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-09-18 12:11:22 +02:00
Manuel Pégourié-Gonnard 2a59fb45b5 Add explicit cast when truncating values
MSVC complains about it otherwise.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-09-18 12:11:22 +02:00
Manuel Pégourié-Gonnard 6e2a9a7faa Factor repeated code in ssl_cf functions
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-09-18 12:11:21 +02:00
Manuel Pégourié-Gonnard 2ddec4306f Use bit operations for constant-flow padding check
The previous code used comparison operators >= and == that are quite likely to
be compiled to branches by some compilers on some architectures (with some
optimisation levels).

For example, take the following function:

void old_update( size_t data_len, size_t *padlen )
{
    *padlen  *= ( data_len >= *padlen + 1 );
}

With Clang 3.8, let's compile it for the Arm v6-M architecture:

% clang --target=arm-none-eabi -march=armv6-m -Os foo.c -S -o - |
    sed -n '/^old_update:$/,/\.size/p'

old_update:
        .fnstart
@ BB#0:
        .save   {r4, lr}
        push    {r4, lr}
        ldr     r2, [r1]
        adds    r4, r2, #1
        movs    r3, #0
        cmp     r4, r0
        bls     .LBB0_2
@ BB#1:
        mov     r2, r3
.LBB0_2:
        str     r2, [r1]
        pop     {r4, pc}
.Lfunc_end0:
        .size   old_update, .Lfunc_end0-old_update

We can see an unbalanced secret-dependant branch, resulting in a total
execution time depends on the value of the secret (here padlen) in a
straightforward way.

The new version, based on bit operations, doesn't have this issue:

new_update:
        .fnstart
@ BB#0:
        ldr     r2, [r1]
        subs    r0, r0, #1
        subs    r0, r0, r2
        asrs    r0, r0, #31
        bics    r2, r0
        str     r2, [r1]
        bx      lr
.Lfunc_end1:
        .size   new_update, .Lfunc_end1-new_update

(As a bonus, it's smaller and uses less stack.)

While there's no formal guarantee that the version based on bit operations in
C won't be translated using branches by the compiler, experiments tend to show
that's the case [1], and it is commonly accepted knowledge in the practical
crypto community that if we want to sick to C, bit operations are the safest
bet [2].

[1] https://github.com/mpg/ct/blob/master/results
[2] https://github.com/veorq/cryptocoding

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-09-18 12:10:33 +02:00
Janos Follath d2ce916b58 Merge branch 'development-restricted' 2020-08-26 14:15:34 +01:00
Janos Follath d4ac4e037b
Merge pull request #736 from mpg/cf-varpos-copy-dev-restricted
Constant-flow copy of HMAC from variable position
2020-08-25 14:35:55 +01:00
Gilles Peskine ed19762a22
Merge pull request #3574 from makise-homura/e2k_support
Support building on e2k (Elbrus) architecture
2020-08-25 09:46:36 +02:00
makise-homura af9513bb48 A different approach of signed-to-unsigned comparison
Suggsted by @hanno-arm

Signed-off-by: makise-homura <akemi_homura@kurisa.ch>
2020-08-24 23:42:49 +03:00
Manuel Pégourié-Gonnard ba6fc9796a Fix a typo in a comment
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-08-24 12:59:55 +02:00
Dan Handley abccfc1684 Merge development into development-restricted
* development:
  Update copyright notices to use Linux Foundation guidance
  Undef ASSERT before defining it to ensure that no previous definition has sneaked in through included files.
  Add ChangeLog entry for X.509 CN-type vulnerability
  Improve documentation of cn in x509_crt_verify()
  Fix comparison between different name types
  Add test: DNS names should not match IP addresses
  Remove obsolete buildbot reference in compat.sh
  Fix misuse of printf in shell script
  Fix added proxy command when IPv6 is used
  Simplify test syntax
  Fix logic error in setting client port
  ssl-opt.sh: include test name in log files
  ssl-opt.sh: remove old buildbot-specific condition
  ssl-opt.sh: add proxy to all DTLS tests

Signed-off-by: Dan Handley <dan.handley@arm.com>
2020-08-20 11:07:12 +01:00
Manuel Pégourié-Gonnard de1cf2c5e1 Make mbedtls_ssl_cf_memcpy_offset() constant-flow
all.sh component test_valgrind_constant_flow is now passing.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-08-20 10:22:41 +02:00
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
Bence Szépkúti 1e14827beb Update copyright notices to use Linux Foundation guidance
As a result, the copyright of contributors other than Arm is now
acknowledged, and the years of publishing are no longer tracked in the
source files.

Also remove the now-redundant lines declaring that the files are part of
MbedTLS.

This commit was generated using the following script:

# ========================
#!/bin/sh

# Find files
find '(' -path './.git' -o -path './3rdparty' ')' -prune -o -type f -print | xargs sed -bi '

# Replace copyright attribution line
s/Copyright.*Arm.*/Copyright The Mbed TLS Contributors/I

# Remove redundant declaration and the preceding line
$!N
/This file is part of Mbed TLS/Id
P
D
'
# ========================

Signed-off-by: Bence Szépkúti <bence.szepkuti@arm.com>
2020-08-19 10:35:41 +02:00
makise-homura 0be6aa9957 Get back -Wsign-compare and fix sources according to it
Signed-off-by: makise-homura <akemi_homura@kurisa.ch>
2020-08-18 23:52:53 +03:00
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 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 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
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
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 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
Manuel Pégourié-Gonnard 8aa29e382f Use existing implementation of cf_hmac()
Just move code from ssl_decrypt_buf() to the new cf_hmac() function and then
call cf_hmac() from there.

This makes the new cf_hmac() function used, opening the door for making it
static in the next commit. It also validates that its interface works for
using it in ssl_decrypt_buf().

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-15 12:26:21 +02:00
Manuel Pégourié-Gonnard 045f094c81 Add dummy constant-flow HMAC function with tests
The dummy implementation is not constant-flow at all for now, it's just
here as a starting point and a support for developing the tests and putting
the infrastructure in place.

Depending on the implementation strategy, there might be various corner cases
depending on where the lengths fall relative to block boundaries. So it seems
safer to just test all possible lengths in a given range than to use only a
few randomly-chosen values.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-15 12:25:52 +02:00
Manuel Pégourié-Gonnard 2df1f1f16f Factor repeated preprocessor condition to a macro
The condition is a complex and repeated a few times. There were already some
inconsistencies in the repetitions as some of them forgot about DES.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-09 12:13:31 +02:00
Manuel Pégourié-Gonnard 527b87890d
Merge pull request #3454 from gilles-peskine-arm/include-common-h-development
Include common.h from all library source files
2020-07-03 09:44:18 +02:00
Gilles Peskine db09ef6d22 Include common.h instead of config.h in library source files
In library source files, include "common.h", which takes care of
including "mbedtls/config.h" (or the alternative MBEDTLS_CONFIG_FILE)
and other things that are used throughout the library.

FROM=$'#if !defined(MBEDTLS_CONFIG_FILE)\n#include "mbedtls/config.h"\n#else\n#include MBEDTLS_CONFIG_FILE\n#endif' perl -i -0777 -pe 's~\Q$ENV{FROM}~#include "common.h"~' library/*.c 3rdparty/*/library/*.c scripts/data_files/error.fmt scripts/data_files/version_features.fmt

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2020-07-02 11:26:57 +02:00
Manuel Pégourié-Gonnard f4e3fc9133 Use starts/finish around Lucky 13 dummy compressions
Fixes #3246

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-06-15 11:55:53 +02:00
Hanno Becker f486e28694 Document precondition of nonce-generating function in ssl_msg.c
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-06-04 13:33:08 +01:00
Hanno Becker 15952814d8 Improve documentation of nonce-generating function in ssl_msg.c
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-06-04 13:31:46 +01:00