Commit Graph

15716 Commits

Author SHA1 Message Date
Hanno Becker
77e4f485e1 Move illustration of (un)supported cases in MPS reader documentation
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
97c8e930e2 Fix diagram in documentation of MPS reader
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
1682a8b6fe Don't use abbreviated names for local variables in MPS reader
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
b9c086adc5 Use int pointer for paused param in mbedtls_mps_reader_reclaim()
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
fea81b3997 Improve and fix wording in MPS reader documentation
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
f1cfa319c4 Fix typos in documentation of MBEDTLS_ERR_MPS_READER_NEED_MORE
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
d913e2e982 Remove duplicate definition of MBEDTLS_MPS_ERR_BASE
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
4a079c5be7 Fix documentation for mbedtls_mps_[stored_]size_t
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
46101c76f9 Improve wording of documentation of mbedtls_mps_size_t
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
6e3484e123 Clarify documentation of MBEDTLS_MPS_STATE_VALIDATION
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
53314aade1 Adjust spacing for MPS reader entries in library/Makefile
Existing entries use combination of tabs and spaces, for whatever reason.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
3d0db81690 Fix typo in MPS reader documentation
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
8fc107c9fb Clarify wording in MPS reader documentation
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
a408c1719c Clarify wording in MPS reader documentation
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
49cc1317b0 Fix typo in MPS reader documentation
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
b1855434eb Rename mbedtls_mps_reader::acc_avail -> acc_available
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
f81e41f1e4 Improve readability of MPS reader implementation
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
0bea62f2d7 Fix typo in reader documentation
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
4f84e20eb0 Don't invalidate MPS reader buffers upon commit call
Previously, the semantics of mbedtls_mps_reader_commit() was to invalidate
all buffers previously fetched via mbedtls_mps_reader_get(), forbidding
any further use by the 'consumer'. This was in fact a necessary constraint
for the current implementation, which did some memory moving in
mbedtls_mps_reader_commit().

This commit simplifies the reader's semantics and implementation in
the following way:

- API: A call to mbedtls_mps_reader_commit() does no longer invalidate
       the buffers previously obtained via mbedtls_mps_reader_get().
       Instead, they can continue to be used until
       mbedtls_mps_reader_reclaim() is called.

       Calling mbedtls_mps_reader_commit() now only sets a marker
       indicating which parts of the data received through
       mbedtls_mps_reader_get() need not be backed up once
       mbedtls_mps_reader_reclaim() is called. Allowing the user
       to call mbedtls_mbedtls_reader_commit() multiple times
       before mbedtls_mps_reader_reclaim() is mere convenience:
       We'd get exactly the same functionality if instead of
       mbedtls_mps_reader_commit(), there was an additional argument
       to mbedtls_mps_reader_reclaim() indicating how much data
       to retain. However, the present design is more convenient
       for the user and doesn't appear to introduce any unnecessary
       complexity (anymore), so we stick with it for now.

- Implementation: mbedtls_mps_reader_commit() is now a 1-liner,
                  setting the 'commit-marker', but doing nothing else.

                  Instead, the complexity of mbedtls_mp_reader_reclaim()
                  slightly increases because it has to deal with creating
                  backups from both the accumulator and the current
                  fragment. In the previous implementation, which shifted
                  the accumulator content with every call to
                  mbedtls_mps_reader_commit(), only the backup from the
                  fragment was necessary; with the new implementation
                  which doesn't shift anything in
                  mbedtls_mps_reader_commit(), we need to do the
                  accumulator shift in mbedtls_mps_reader_reclaim().

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
014f683ca9 Test MPS reader when reclaim fails because the acc is too small
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
bc64f945e4 Update VS2010 project file
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:20:18 +01:00
Hanno Becker
8899396fd1 Move MPS reader to mbedtls_mps_ namespace
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
984fbded58 Move MPS trace macros to MBEDTLS_MPS_ namespace
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
c518c3b7bb Rename MPS files library/mps/xxx.[ch] to library/mps_xxx.[ch]
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
b910016049 Add MPS trace module implementation
This commit adds an implementation of the MPS trace module
based on `printf()`.

The enabling macro MBEDTLS_MPS_TRACE remains unset by default
because MPS tracing is very verbose and consumes unnecessary
space in the CI.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
2b8bad3e80 MPS Reader Tests: Test feed() of NULL buffer
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
223b72e40e MPS Reader Tests: Exercise inconsistent reads after pausing
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
714cbeb4f5 MPS Reader Tests: Add random test
This commit adds a test exercising the reader in a random way
and comparing the outcomes against what we expect based on the
abstract model of the reader from the producer's and consumer's
perspective.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
b6fdd35a38 MPS Reader Tests: Use accumulator multiple times
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
e1f173c36f MPS Reader Tests: Continue fetching after reclaim() was rejected
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
cb2a88ed38 MPS Reader Tests: Attempt reclaim while more data is available
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
aac41225d3 MPS Reader Tests: Test multiple feed() calls to fulfill read request
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
e82952acb3 MPS Reader Tests: Test use of accumulator
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
caf1a3f663 MPS Reader Tests: Accumulator too small
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
7d86b74cef MPS Reader Tests: Request more data than what's available
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
7973b2dcac MPS Reader Tests: Test two rounds of fetching in multiple steps
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
dbd8a96487 MPS Reader Tests: Add test for feed-{get,get,...}-commit-reclaim
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
0e4edfc083 MPS Reader Tests: Add test for >1 feed-get-commit-reclaim cycles
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
09d880aa38 MPS Reader Tests: Test basic feed-get-commit-reclaim cycle
This commit adds an MPS unit test suite `test_suite_mps` which will
subsequently be populated with unit tests for all components of MPS.

As a start, a test case

```
   mbedtls_mps_reader_no_pausing_single_step_single_round()
```

is added which exercises the most basic usage of the MPS reader
component; see the test case description for more details.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
ac267f3485 Add MPS configuration option for state validation
See the documentation in library/mps/common.h which
this commit modifies.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
447e8a5ecd Add internal header for MPS errors
This commit adds an internal header `library/mps/error.h` related
to error codes in MPS.

For now, those error codes can be considered internal and thus we
don't have to avoid clashes with other Mbed TLS error codes. This
is OK as long as it's true that MPS isn't public API, and its error
codes are never forwarded to the return values of public API calls.

The error code allocation of MPS will likely need revisiting over time.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
75ac1f7b95 Add implementation for MPS assertion macros
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
0ea0db4368 Add MPS reader translation unit to Makefile and CMakeLists
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
d2f9f53f7f Add typedef's for MPS buffer size types
Most buffers that MPS deals with are small and representable
with integer types of width 16-bit or more.

For highly memory constrained systems, it is therefore a potential
for significant memory savings to use 16-bit types for buffer sizes
throughout MPS.

In prepraration for this, this commit introduces typdefs

```
   mbedtls_mps_size_t
   mbedtls_mps_stored_size_t
```

for buffer sizes in the MPS implementation and the MPS structures,
respectively.

So far, those MUST be defined as `size_t`: While an effort has been made
to write most of MPS code in terms of `mbedtls_mps_[stored_]size_t` in a
way that would allow narrower types, those aren't yet supported. Still,
we retain the typedefs in order to avoid unnecessary rewriting of a large
body of the MPS codebase.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
13cd7846a0 Add MPS reader implementation
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
1c0cd10ea8 Add header and documentation for MPS reader
This commit adds the interface fo the MPS reader component as
`library/mps/reader.h`.

Please see the file itself for extensive documentation.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
c809ff6ef6 Add stub implementation for MPS tracing API
MPS' tracing module uses four macros:

1) TRACE( type, fmt, ... )

   This acts like `printf( fmt, ... )` but also allows
   the specification of a type of trace output (comment,
   warning, error, ...)

2) TRACE_INIT

   This acts like TRACE() but increases the level of
   indentation. It will be used at the beginning of
   function calls.

3) RETURN( val )

   Equivalent to `return( val )` plus a decrement in the
   level of indentation. This should be used at the end of
   functions that have been started with TRACE_INIT.

4) TRACE_END

   This combines a trace output with a decrement of the
   level of indentation. It's necessary prior to leaving
   functions which have been started with TRACE_INIT
   but which don't have a return value.

This commit defines those macros as no-op dummies in
`library/mps/trace.h` for now.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
1ae9f756ba Add MPS compile-time option for enabling/disabling tracing
This commit adds an MPS-specific compile-time option
`MBEDTLS_MPS_TRACE` to the internal MPS header `mps/common.h`.

So far -- this may need revisiting -- MPS comes with its own
internal tracing module which allows to track the operation of
MPS' various layers for the purpose of understanding of it workings
as well as for debugging.

The reasons for the introduction of a module separate from SSL debug
are the following:

1) The SSL debug module requires an SSL context to function because
   debug callbacks are part of the runtime configuration of the SSL
   module.

   The MPS tracing module, in contrast, is not supposed to be used
   in production environments, and there is no need for a runtime
   configuration. Instead, a compile-time defined tracing callback
   is used.

2) In the interest of modularity, MPS' tracing module shouldn't
   require having an SSL context around.

3) Purely visually, MPS' tracing module adds support for indentation
   according to call-depth and coloring according to which module is
   being used, which makes it very useful for what's going on; however,
   those features aren't available in the SSL debug module (and they
   shouldn't be).

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
6ed183cf00 Add MPS compile time option for enabling/disabling assertions
This commit adds the compile-time option MBEDTLS_MPS_ENABLE_ASSERTIONS
which controls the presence of runtime assertions in MPS code.

See the documentation in the header for more information.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00
Hanno Becker
108fc84b04 Add MPS configuration header
This commit introduces the internal MPS header `mps/common.h`
which will subsequently be populated with MPS-specific compile-time
options and helper macros. For now, it's a stub.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00