mirror of
https://github.com/Mbed-TLS/mbedtls.git
synced 2026-05-04 17:12:51 +02:00
Merge remote-tracking branch 'mbedtls4.0.0-documentation' into mbedtls-4.0.0.rc
Signed-off-by: Minos Galanakis <minos.galanakis@arm.com>
This commit is contained in:
Minos Galanakis
26
BRANCHES.md
26
BRANCHES.md
@@ -6,9 +6,8 @@ At any point in time, we have a number of maintained branches, currently consist
|
||||
this always contains the latest release, including all publicly available
|
||||
security fixes.
|
||||
- The [`development`](https://github.com/Mbed-TLS/mbedtls/tree/development) branch:
|
||||
this is where the next major version of Mbed TLS (version 4.0) is being
|
||||
prepared. It has API changes that make it incompatible with Mbed TLS 3.x,
|
||||
as well as all the new features and bug fixes and security fixes.
|
||||
this is where the next minor version of Mbed TLS 4.x is prepared. It contains
|
||||
new features, bug fixes, and security fixes.
|
||||
- One or more long-time support (LTS) branches: these only get bug fixes and
|
||||
security fixes. Currently, the supported LTS branches are:
|
||||
- [`mbedtls-3.6`](https://github.com/Mbed-TLS/mbedtls/tree/mbedtls-3.6).
|
||||
@@ -19,7 +18,7 @@ These branches will not receive any changes or updates.
|
||||
|
||||
We use [Semantic Versioning](https://semver.org/). In particular, we maintain
|
||||
API compatibility in the `main` branch across minor version changes (e.g.
|
||||
the API of 3.(x+1) is backward compatible with 3.x). We only break API
|
||||
the API of 4.(x+1) is backward compatible with 4.x). We only break API
|
||||
compatibility on major version changes (e.g. from 3.x to 4.0). We also maintain
|
||||
ABI compatibility within LTS branches; see the next section for details.
|
||||
|
||||
@@ -66,25 +65,6 @@ crypto that was found to be weak) may need to be changed. In case security
|
||||
comes in conflict with backwards compatibility, we will put security first,
|
||||
but always attempt to provide a compatibility option.
|
||||
|
||||
## Backward compatibility for the key store
|
||||
|
||||
We maintain backward compatibility with previous versions of the
|
||||
PSA Crypto persistent storage since Mbed TLS 2.25.0, provided that the
|
||||
storage backend (PSA ITS implementation) is configured in a compatible way.
|
||||
We intend to maintain this backward compatibility throughout a major version
|
||||
of Mbed TLS (for example, all Mbed TLS 3.y versions will be able to read
|
||||
keys written under any Mbed TLS 3.x with x <= y).
|
||||
|
||||
Mbed TLS 3.x can also read keys written by Mbed TLS 2.25.0 through 2.28.x
|
||||
LTS, but future major version upgrades (for example from 2.28.x/3.x to 4.y)
|
||||
may require the use of an upgrade tool.
|
||||
|
||||
Note that this guarantee does not currently fully extend to drivers, which
|
||||
are an experimental feature. We intend to maintain compatibility with the
|
||||
basic use of drivers from Mbed TLS 2.28.0 onwards, even if driver APIs
|
||||
change. However, for more experimental parts of the driver interface, such
|
||||
as the use of driver state, we do not yet guarantee backward compatibility.
|
||||
|
||||
## Long-time support branches
|
||||
|
||||
For the LTS branches, additionally we try very hard to also maintain ABI
|
||||
|
||||
143
README.md
143
README.md
@@ -1,55 +1,62 @@
|
||||
README for Mbed TLS
|
||||
===================
|
||||
|
||||
Mbed TLS is a C library that implements cryptographic primitives, X.509 certificate manipulation and the SSL/TLS and DTLS protocols. Its small code footprint makes it suitable for embedded systems.
|
||||
|
||||
Mbed TLS includes a reference implementation of the [PSA Cryptography API](#psa-cryptography-api). This is currently a preview for evaluation purposes only.
|
||||
Mbed TLS is a C library that implements X.509 certificate manipulation and the TLS and DTLS protocols. Its small code footprint makes it suitable for embedded systems.
|
||||
Mbed TLS includes the [TF-PSA-Crypto repository](https://github.com/Mbed-TLS/TF-PSA-Crypto) that provides an implementation of the [PSA Cryptography API](https://arm-software.github.io/psa-api).
|
||||
|
||||
Configuration
|
||||
-------------
|
||||
Configuration options related to X.509 and TLS are available in `include/mbedtls/mbedtls_config.h`, while cryptography and platform options are located in the TF-PSA-Crypto configuration file `tf-psa-crypto/include/psa/crypto_config.h`.
|
||||
|
||||
Mbed TLS should build out of the box on most systems. Some platform specific options are available in the fully documented configuration file `include/mbedtls/mbedtls_config.h`, which is also the place where features can be selected. This file can be edited manually, or in a more programmatic way using the Python 3 script `scripts/config.py` (use `--help` for usage instructions).
|
||||
With the default platform options, Mbed TLS should build out of the box on most systems.
|
||||
|
||||
Compiler options can be set using conventional environment variables such as `CC` and `CFLAGS`.
|
||||
These configuration files can be edited manually, or programmatically using the Python script `scripts/config.py` (run with --help for usage instructions).
|
||||
|
||||
We provide some non-standard configurations focused on specific use cases in the `configs/` directory. You can read more about those in `configs/README.txt`
|
||||
We provide some non-standard configurations focused on specific use cases in the `configs/` directory. You can read more about those in `configs/README.txt`.
|
||||
|
||||
Documentation
|
||||
-------------
|
||||
|
||||
The main Mbed TLS documentation is available via [ReadTheDocs](https://mbed-tls.readthedocs.io/).
|
||||
|
||||
Documentation for the PSA Cryptography API is available [on GitHub](https://arm-software.github.io/psa-api/crypto/).
|
||||
|
||||
To generate a local copy of the library documentation in HTML format, tailored to your compile-time configuration:
|
||||
|
||||
1. Make sure that [Doxygen](http://www.doxygen.nl/) is installed.
|
||||
1. Run `mkdir /path/to/build_dir && cd /path/to/build_dir`
|
||||
1. Run `cmake /path/to/mbedtls/source`
|
||||
1. Run `make apidoc`
|
||||
1. Browse `apidoc/index.html` or `apidoc/modules.html`.
|
||||
1. Run `cmake -B /path/to/build_dir /path/to/mbedtls/source`
|
||||
1. Run `cmake --build /path/to/build_dir --target mbedtls-apidoc`
|
||||
1. Open one of the main generated HTML files:
|
||||
* `apidoc/index.html`
|
||||
* `apidoc/modules.html` or `apidoc/topics.html`
|
||||
|
||||
For other sources of documentation, see the [SUPPORT](SUPPORT.md) document.
|
||||
|
||||
Compiling
|
||||
---------
|
||||
|
||||
We use CMake to configure and drive our build process. Three libraries are built: libtfpsacrypto, libmbedx509, and libmbedtls. Note that libmbedtls depends on libmbedx509 and libtfpsacrypto, and libmbedx509 depends on libtfpsacrypto. As a result, some linkers will expect flags to be in a specific order, for example the GNU linker wants `-lmbedtls -lmbedx509 -ltfpsacrypto`.
|
||||
We use CMake to configure and drive our build process. Three libraries are built: `libtfpsacrypto`, `libmbedx509`, and `libmbedtls`. Note that `libmbedtls` depends on `libmbedx509` and `libtfpsacrypto`, and `libmbedx509` depends on `libtfpsacrypto`. As a result, some linkers will expect flags to be in a specific order, for example the GNU linker wants `-lmbedtls -lmbedx509 -ltfpsacrypto`. The cryptographic library `libtfpsacrypto` is also provided under its legacy name, `libmbedcrypto`.
|
||||
|
||||
### Tool versions
|
||||
|
||||
You need the following tools to build the library:
|
||||
You need the following tools to build the library from the main branch with the provided CMake files. Mbed TLS minimum tool version requirements are set based on the versions shipped in the latest or penultimate (depending on the release cadence) long-term support releases of major Linux distributions, namely at time of writing: Ubuntu 22.04, RHEL 9, and SLES 15 SP4.
|
||||
|
||||
* CMake 3.10.2 or later.
|
||||
* A build system that CMake supports.
|
||||
* A C99 toolchain (compiler, linker, archiver). We actively test with GCC 5.4, Clang 3.8, Arm Compiler 6, IAR 8 and Visual Studio 2017. More recent versions should work. Slightly older versions may work.
|
||||
* Python 3.8 to generate the test code. Python is also needed to integrate PSA drivers and to build the development branch (see next section).
|
||||
* CMake 3.20.2 or later.
|
||||
* A build system like Make or Ninja for which CMake can generate build files.
|
||||
* A C99 toolchain (compiler, linker, archiver). We actively test with GCC 5.4, Clang 3.8, Arm Compiler 6, and Visual Studio 2017 Compiler. More recent versions should work. Slightly older versions may work.
|
||||
* Python 3.8 or later to generate the test code. Python is also needed to build the development branch (see next section).
|
||||
* Perl to run the tests, and to generate some source files in the development branch.
|
||||
* Doxygen 1.8.11 or later (if building the documentation; slightly older versions should work).
|
||||
* Doxygen 1.8.14 or later (if building the documentation; slightly older versions should work).
|
||||
|
||||
### Git usage
|
||||
|
||||
The `development` branch and the `mbedtls-3.6` long-term support branch of Mbed TLS use a [Git submodule](https://git-scm.com/book/en/v2/Git-Tools-Submodules#_cloning_submodules) ([framework](https://github.com/Mbed-TLS/mbedtls-framework)). This is not needed to merely compile the library at a release tag. This is not needed to consume a release archive (zip or tar).
|
||||
The supported branches (see [`BRANCHES.md`](BRANCHES.md)) use [Git submodules](https://git-scm.com/book/en/v2/Git-Tools-Submodules#_cloning_submodules). They contain two submodules: the [framework](https://github.com/Mbed-TLS/mbedtls-framework) submodule and the [tf-psa-crypto](https://github.com/Mbed-TLS/TF-PSA-Crypto) submodule, except for the 3.6 LTS branch, which contains only the framework submodule. Release tags also use Git submodules.
|
||||
|
||||
After cloning or checking out a branch or tag, run:
|
||||
```
|
||||
git submodule update --init --recursive
|
||||
```
|
||||
to initialize and update the submodules before building.
|
||||
|
||||
However, the official source release tarballs (e.g. [mbedtls-4.0.0-beta.tar.bz2](https://github.com/Mbed-TLS/mbedtls/releases/download/mbedtls-4.0.0-beta/mbedtls-4.0.0-beta.tar.bz2)) include the contents of the submodules.
|
||||
|
||||
### Generated source files in the development branch
|
||||
|
||||
@@ -57,12 +64,12 @@ The source code of Mbed TLS includes some files that are automatically generated
|
||||
|
||||
The following tools are required:
|
||||
|
||||
* Perl, for some library source files and for Visual Studio build files.
|
||||
* Python 3.8 and some Python packages, for some library source files, sample programs and test data. To install the necessary packages, run:
|
||||
* Perl, for some library source files.
|
||||
* Python 3 and some Python packages, for some library source files, sample programs and test data. To install the necessary packages, run:
|
||||
```
|
||||
python3 -m pip install --user -r scripts/basic.requirements.txt
|
||||
```
|
||||
Depending on your Python installation, you may need to invoke `python` instead of `python3`. To install the packages system-wide, omit the `--user` option.
|
||||
Depending on your Python installation, you may need to invoke `python` instead of `python3`. To install the packages system-wide or in a virtual environment, omit the `--user` option.
|
||||
* A C compiler for the host platform, for some test data.
|
||||
|
||||
The scripts that generate the configuration-independent files will look for a host C compiler in the following places (in order of preference):
|
||||
@@ -90,14 +97,10 @@ In order to run the tests, enter:
|
||||
|
||||
ctest
|
||||
|
||||
The test suites need Python to be built and Perl to be executed. If you don't have one of these installed, you'll want to disable the test suites with:
|
||||
The test suites need Python to be built. If you don't have Python installed, you'll want to disable the test suites with:
|
||||
|
||||
cmake -DENABLE_TESTING=Off /path/to/mbedtls_source
|
||||
|
||||
If you disabled the test suites, but kept the programs enabled, you can still run a much smaller set of tests with:
|
||||
|
||||
programs/test/selftest
|
||||
|
||||
To configure CMake for building shared libraries, use:
|
||||
|
||||
cmake -DUSE_SHARED_MBEDTLS_LIBRARY=On /path/to/mbedtls_source
|
||||
@@ -109,9 +112,11 @@ There are many different build types available with CMake. Most of them are avai
|
||||
- `Coverage`. This generates code coverage information in addition to debug information.
|
||||
- `ASan`. This instruments the code with AddressSanitizer to check for memory errors. (This includes LeakSanitizer, with recent version of gcc and clang.) (With recent version of clang, this mode also instruments the code with UndefinedSanitizer to check for undefined behaviour.)
|
||||
- `ASanDbg`. Same as ASan but slower, with debug information and better stack traces.
|
||||
- `MemSan`. This instruments the code with MemorySanitizer to check for uninitialised memory reads. Experimental, needs recent clang on Linux/x86\_64.
|
||||
- `MemSan`. This instruments the code with MemorySanitizer to check for uninitialised memory reads.
|
||||
- `MemSanDbg`. Same as MemSan but slower, with debug information, better stack traces and origin tracking.
|
||||
- `Check`. This activates the compiler warnings that depend on optimization and treats all warnings as errors.
|
||||
- `TSan`. This instruments the code with ThreadSanitizer to detect data races and other threading-related concurrency issues at runtime.
|
||||
- `TSanDbg`. Same as TSan but slower, with debug information, better stack traces and origin tracking.
|
||||
|
||||
Switching build types in CMake is simple. For debug mode, enter at the command line:
|
||||
|
||||
@@ -130,7 +135,7 @@ for example:
|
||||
CC=your_cc cmake /path/to/mbedtls_source
|
||||
|
||||
If you already invoked cmake and want to change those settings, you need to
|
||||
remove the build directory and create it again.
|
||||
invoke the configuration phase of CMake again with the new settings.
|
||||
|
||||
Note that it is possible to build in-place; this will however overwrite the
|
||||
legacy Makefiles still used for testing purposes (see
|
||||
@@ -139,7 +144,7 @@ showing them as modified). In order to do so, from the Mbed TLS source
|
||||
directory, use:
|
||||
|
||||
cmake .
|
||||
make
|
||||
cmake --build .
|
||||
|
||||
If you want to change `CC` or `CFLAGS` afterwards, you will need to remove the
|
||||
CMake cache. This can be done with the following command using GNU find:
|
||||
@@ -149,25 +154,31 @@ CMake cache. This can be done with the following command using GNU find:
|
||||
You can now make the desired change:
|
||||
|
||||
CC=your_cc cmake .
|
||||
make
|
||||
cmake --build .
|
||||
|
||||
Regarding variables, also note that if you set CFLAGS when invoking cmake,
|
||||
your value of CFLAGS doesn't override the content provided by cmake (depending
|
||||
your value of CFLAGS doesn't override the content provided by CMake (depending
|
||||
on the build mode as seen above), it's merely prepended to it.
|
||||
|
||||
#### Consuming Mbed TLS
|
||||
|
||||
Mbed TLS provides a package config file for consumption as a dependency in other
|
||||
CMake projects. You can include Mbed TLS's CMake targets yourself with:
|
||||
Mbed TLS provides a CMake package configuration file for consumption as a
|
||||
dependency in other CMake projects. You can load its CMake targets with:
|
||||
|
||||
find_package(MbedTLS)
|
||||
find_package(MbedTLS REQUIRED)
|
||||
|
||||
If prompted, set `MbedTLS_DIR` to `${YOUR_MBEDTLS_INSTALL_DIR}/cmake`. This
|
||||
creates the following targets:
|
||||
You can help CMake find the package:
|
||||
|
||||
- `MbedTLS::tfpsacrypto` (Crypto library)
|
||||
- `MbedTLS::mbedtls` (TLS library)
|
||||
- `MbedTLS::mbedx509` (X509 library)
|
||||
- By setting the variable `MbedTLS_DIR` to `${YOUR_MBEDTLS_BUILD_DIR}/cmake`,
|
||||
as shown in `programs/test/cmake_package/CMakeLists.txt`, or
|
||||
- By adding the Mbed TLS installation prefix to `CMAKE_PREFIX_PATH`,
|
||||
as shown in `programs/test/cmake_package_install/CMakeLists.txt`.
|
||||
|
||||
After a successful `find_package(MbedTLS)`, the following imported targets are available:
|
||||
|
||||
- `MbedTLS::tfpsacrypto`, the crypto library
|
||||
- `MbedTLS::mbedtls`, the TLS library
|
||||
- `MbedTLS::mbedx509`, the X.509 library
|
||||
|
||||
You can then use these directly through `target_link_libraries()`:
|
||||
|
||||
@@ -188,14 +199,6 @@ Mbed TLS supports being built as a CMake subproject. One can
|
||||
use `add_subdirectory()` from a parent CMake project to include Mbed TLS as a
|
||||
subproject.
|
||||
|
||||
### Microsoft Visual Studio
|
||||
|
||||
The build files for Microsoft Visual Studio are generated for Visual Studio 2017.
|
||||
|
||||
The solution file `mbedTLS.sln` contains all the basic projects needed to build the library and all the programs. The files in tests are not generated and compiled, as these need Python and perl environments as well. However, the selftest program in `programs/test/` is still available.
|
||||
|
||||
In the development branch of Mbed TLS, the Visual Studio solution files need to be generated first as described in [“Generated source files in the development branch”](#generated-source-files-in-the-development-branch).
|
||||
|
||||
Example programs
|
||||
----------------
|
||||
|
||||
@@ -205,14 +208,13 @@ Please note that the goal of these sample programs is to demonstrate specific fe
|
||||
Tests
|
||||
-----
|
||||
|
||||
Mbed TLS includes an elaborate test suite in `tests/` that initially requires Python to generate the tests files (e.g. `test\_suite\_ssl.c`). These files are generated from a `function file` (e.g. `suites/test\_suite\_ssl.function`) and a `data file` (e.g. `suites/test\_suite\_ssl.data`). The `function file` contains the test functions. The `data file` contains the test cases, specified as parameters that will be passed to the test function.
|
||||
Mbed TLS includes an elaborate test suite in `tests/` that initially requires Python to generate the tests files (e.g. `test_suite_ssl.c`). These files are generated from a `function file` (e.g. `suites/test_suite_ssl.function`) and a `data file` (e.g. `suites/test_suite_ssl.data`). The `function file` contains the test functions. The `data file` contains the test cases, specified as parameters that will be passed to the test function.
|
||||
|
||||
For machines with a Unix shell and OpenSSL (and optionally GnuTLS) installed, additional test scripts are available:
|
||||
|
||||
- `tests/ssl-opt.sh` runs integration tests for various TLS options (renegotiation, resumption, etc.) and tests interoperability of these options with other implementations.
|
||||
- `tests/compat.sh` tests interoperability of every ciphersuite with other implementations.
|
||||
- `tests/scripts/test-ref-configs.pl` test builds in various reduced configurations.
|
||||
- `tests/scripts/depends.py` test builds in configurations with a single curve, key exchange, hash, cipher, or pkalg on.
|
||||
- `tests/scripts/depends.py` tests builds in configurations with a single curve, key exchange, hash, cipher, or pkalg on.
|
||||
- `tests/scripts/all.sh` runs a combination of the above tests, plus some more, with various build options (such as ASan, full `mbedtls_config.h`, etc).
|
||||
|
||||
Instead of manually installing the required versions of all tools required for testing, it is possible to use the Docker images from our CI systems, as explained in [our testing infrastructure repository](https://github.com/Mbed-TLS/mbedtls-test/blob/main/README.md#quick-start).
|
||||
@@ -236,48 +238,11 @@ Mbed TLS is mostly written in portable C99; however, it has a few platform requi
|
||||
- Mixed-endian platforms are not supported.
|
||||
- SIZE_MAX must be at least as big as INT_MAX and UINT_MAX.
|
||||
|
||||
PSA cryptography API
|
||||
--------------------
|
||||
|
||||
### PSA API
|
||||
|
||||
Arm's [Platform Security Architecture (PSA)](https://developer.arm.com/architectures/security-architectures/platform-security-architecture) is a holistic set of threat models, security analyses, hardware and firmware architecture specifications, and an open source firmware reference implementation. PSA provides a recipe, based on industry best practice, that allows security to be consistently designed in, at both a hardware and firmware level.
|
||||
|
||||
The [PSA cryptography API](https://arm-software.github.io/psa-api/crypto/) provides access to a set of cryptographic primitives. It has a dual purpose. First, it can be used in a PSA-compliant platform to build services, such as secure boot, secure storage and secure communication. Second, it can also be used independently of other PSA components on any platform.
|
||||
|
||||
The design goals of the PSA cryptography API include:
|
||||
|
||||
* The API distinguishes caller memory from internal memory, which allows the library to be implemented in an isolated space for additional security. Library calls can be implemented as direct function calls if isolation is not desired, and as remote procedure calls if isolation is desired.
|
||||
* The structure of internal data is hidden to the application, which allows substituting alternative implementations at build time or run time, for example, in order to take advantage of hardware accelerators.
|
||||
* All access to the keys happens through key identifiers, which allows support for external cryptoprocessors that is transparent to applications.
|
||||
* The interface to algorithms is generic, favoring algorithm agility.
|
||||
* The interface is designed to be easy to use and hard to accidentally misuse.
|
||||
|
||||
Arm welcomes feedback on the design of the API. If you think something could be improved, please open an issue on our Github repository. Alternatively, if you prefer to provide your feedback privately, please email us at [`mbed-crypto@arm.com`](mailto:mbed-crypto@arm.com). All feedback received by email is treated confidentially.
|
||||
|
||||
### PSA implementation in Mbed TLS
|
||||
|
||||
Mbed TLS includes a reference implementation of the PSA Cryptography API.
|
||||
However, it does not aim to implement the whole specification; in particular it does not implement all the algorithms.
|
||||
|
||||
### PSA drivers
|
||||
|
||||
Mbed TLS supports drivers for cryptographic accelerators, secure elements and random generators. This is work in progress. Please note that the driver interfaces are not fully stable yet and may change without notice. We intend to preserve backward compatibility for application code (using the PSA Crypto API), but the code of the drivers may have to change in future minor releases of Mbed TLS.
|
||||
|
||||
Please see the [PSA driver example and guide](https://github.com/Mbed-TLS/TF-PSA-Crypto/blob/development/docs/psa-driver-example-and-guide.md) for information on writing a driver.
|
||||
|
||||
License
|
||||
-------
|
||||
|
||||
Unless specifically indicated otherwise in a file, Mbed TLS files are provided under a dual [Apache-2.0](https://spdx.org/licenses/Apache-2.0.html) OR [GPL-2.0-or-later](https://spdx.org/licenses/GPL-2.0-or-later.html) license. See the [LICENSE](LICENSE) file for the full text of these licenses, and [the 'License and Copyright' section in the contributing guidelines](CONTRIBUTING.md#License-and-Copyright) for more information.
|
||||
|
||||
### Third-party code included in Mbed TLS
|
||||
|
||||
This project contains code from other projects. This code is located within the `tf-psa-crypto/drivers/` directory. The original license text is included within project subdirectories, where it differs from the normal Mbed TLS license, and/or in source files. The projects are listed below:
|
||||
|
||||
* `drivers/everest/`: Files stem from [Project Everest](https://project-everest.github.io/) and are distributed under the Apache 2.0 license.
|
||||
* `drivers/p256-m/p256-m/`: Files have been taken from the [p256-m](https://github.com/mpg/p256-m) repository. The code in the original repository is distributed under the Apache 2.0 license. It is distributed in Mbed TLS under a dual Apache-2.0 OR GPL-2.0-or-later license with permission from the author.
|
||||
|
||||
Contributing
|
||||
------------
|
||||
|
||||
|
||||
37
SECURITY.md
37
SECURITY.md
@@ -37,10 +37,6 @@ being implemented. (For example Mbed TLS alone won't guarantee that the
|
||||
messages will arrive without delay, as the TLS protocol doesn't guarantee that
|
||||
either.)
|
||||
|
||||
**Warning!** Block ciphers do not yet achieve full protection against attackers
|
||||
who can measure the timing of packets with sufficient precision. For details
|
||||
and workarounds see the [Block Ciphers](#block-ciphers) section.
|
||||
|
||||
### Local attacks
|
||||
|
||||
In this section, we consider an attacker who can run software on the same
|
||||
@@ -69,9 +65,6 @@ physical side channels as well. Remote and physical timing attacks are covered
|
||||
in the [Remote attacks](remote-attacks) and [Physical
|
||||
attacks](physical-attacks) sections respectively.
|
||||
|
||||
**Warning!** Block ciphers do not yet achieve full protection. For
|
||||
details and workarounds see the [Block Ciphers](#block-ciphers) section.
|
||||
|
||||
#### Local non-timing side channels
|
||||
|
||||
The attacker code running on the platform has access to some sensor capable of
|
||||
@@ -115,36 +108,6 @@ protection against a class of attacks outside of the above described threat
|
||||
model. Neither does it mean that the failure of such a countermeasure is
|
||||
considered a vulnerability.
|
||||
|
||||
#### Block ciphers
|
||||
|
||||
Currently there are four block ciphers in Mbed TLS: AES, CAMELLIA, ARIA and
|
||||
DES. The pure software implementation in Mbed TLS implementation uses lookup
|
||||
tables, which are vulnerable to timing attacks.
|
||||
|
||||
These timing attacks can be physical, local or depending on network latency
|
||||
even a remote. The attacks can result in key recovery.
|
||||
|
||||
**Workarounds:**
|
||||
|
||||
- Turn on hardware acceleration for AES. This is supported only on selected
|
||||
architectures and currently only available for AES. See configuration options
|
||||
`MBEDTLS_AESCE_C`, `MBEDTLS_AESNI_C` for details.
|
||||
- Add a secure alternative implementation (typically hardware acceleration) for
|
||||
the vulnerable cipher. See the [Alternative Implementations
|
||||
Guide](docs/architecture/alternative-implementations.md) for more information.
|
||||
- Use cryptographic mechanisms that are not based on block ciphers. In
|
||||
particular, for authenticated encryption, use ChaCha20/Poly1305 instead of
|
||||
block cipher modes. For random generation, use HMAC\_DRBG instead of CTR\_DRBG.
|
||||
|
||||
#### Everest
|
||||
|
||||
The HACL* implementation of X25519 taken from the Everest project only protects
|
||||
against remote timing attacks. (See their [Security
|
||||
Policy](https://github.com/hacl-star/hacl-star/blob/main/SECURITY.md).)
|
||||
|
||||
The Everest variant is only used when `MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED`
|
||||
configuration option is defined. This option is off by default.
|
||||
|
||||
#### Formatting of X.509 certificates and certificate signing requests
|
||||
|
||||
When parsing X.509 certificates and certificate signing requests (CSRs),
|
||||
|
||||
@@ -1,24 +1,28 @@
|
||||
This directory contains example configuration files.
|
||||
|
||||
The examples are generally focused on a particular usage case (eg, support for
|
||||
a restricted number of ciphersuites) and aim at minimizing resource usage for
|
||||
this target. They can be used as a basis for custom configurations.
|
||||
The examples are generally focused on a particular use case (eg, support for
|
||||
a restricted set of ciphersuites) and aim to minimize resource usage for
|
||||
the target. They can be used as a basis for custom configurations.
|
||||
|
||||
These files are complete replacements for the default mbedtls_config.h. To use one of
|
||||
them, you can pick one of the following methods:
|
||||
These files come in pairs and are complete replacements for the default
|
||||
mbedtls_config.h and crypto_config.h. The two files of a pair share the same or
|
||||
very similar name, with the crypto file prefixed by "crypto-". Note
|
||||
that some of the cryptography configuration files may be located in
|
||||
tf-psa-crypto/configs.
|
||||
|
||||
1. Replace the default file include/mbedtls/mbedtls_config.h with the chosen one.
|
||||
To use one of these pairs, you can pick one of the following methods:
|
||||
|
||||
2. Define MBEDTLS_CONFIG_FILE and adjust the include path accordingly.
|
||||
For example, using make:
|
||||
1. Replace the default files include/mbedtls/mbedtls_config.h and
|
||||
tf-psa-crypto/include/psa/crypto_config.h with the chosen ones.
|
||||
|
||||
CFLAGS="-I$PWD/configs -DMBEDTLS_CONFIG_FILE='<foo.h>'" make
|
||||
2. Use the MBEDTLS_CONFIG_FILE and TF_PSA_CRYPTO_CONFIG_FILE CMake options. For
|
||||
example, to build out-of-tree with the config-ccm-psk-tls1_2.h and
|
||||
crypto-config-ccm-psk-tls1_2.h configuration pair:
|
||||
|
||||
Or, using cmake:
|
||||
cmake -DMBEDTLS_CONFIG_FILE="configs/config-ccm-psk-tls1_2.h" \
|
||||
-DTF_PSA_CRYPTO_CONFIG_FILE="configs/crypto-config-ccm-psk-tls1_2.h"
|
||||
-B build-psktls12 .
|
||||
cmake --build build-psktls12
|
||||
|
||||
find . -iname '*cmake*' -not -name CMakeLists.txt -exec rm -rf {} +
|
||||
CFLAGS="-I$PWD/configs -DMBEDTLS_CONFIG_FILE='<foo.h>'" cmake .
|
||||
make
|
||||
|
||||
Note that the second method also works if you want to keep your custom
|
||||
configuration file outside the Mbed TLS tree.
|
||||
The second method also works if you want to keep your custom configuration
|
||||
files outside the Mbed TLS tree.
|
||||
|
||||
File diff suppressed because it is too large
Load Diff
622
docs/4.0-migration-guide.md
Normal file
622
docs/4.0-migration-guide.md
Normal file
@@ -0,0 +1,622 @@
|
||||
# Migrating from Mbed TLS 3.x to Mbed TLS 4.0
|
||||
|
||||
This guide details the steps required to migrate from Mbed TLS version 3.x to Mbed TLS version 4.0 or greater. Unlike normal releases, Mbed TLS 4.0 breaks compatibility with previous versions, so users, integrators and package maintainers might need to change their own code in order to make it work with Mbed TLS 4.0.
|
||||
|
||||
Here's the list of breaking changes; each entry should help you answer these two questions: (1) am I affected? (2) if yes, what's my migration path?
|
||||
|
||||
The changes are detailed below. Here is a summary of the main points:
|
||||
|
||||
- Mbed TLS has been split between two products: TF-PSA-Crypto for cryptography, and Mbed TLS for X.509 and (D)TLS.
|
||||
- CMake is now the only supported build system.
|
||||
- The cryptography API is now mostly the PSA API: most legacy cryptography APIs have been removed. This has led to adaptations in some X.509 and TLS APIs, notably because the library always uses the PSA random generator.
|
||||
- Various deprecated or minor functionality has been removed.
|
||||
|
||||
Please consult the [TF-PSA-Crypto migration guide](../tf-psa-crypto/docs/1.0-migration-guide.md) for all information related to the crytography part of the library.
|
||||
|
||||
## CMake as the only build system
|
||||
Mbed TLS now uses CMake exclusively to configure and drive its build process.
|
||||
Support for the GNU Make and Microsoft Visual Studio project-based build systems has been removed.
|
||||
|
||||
The previous `.sln` and `.vcxproj` files are no longer distributed or generated.
|
||||
|
||||
See the `Compiling` section in README.md for instructions on building the Mbed TLS libraries and tests with CMake.
|
||||
If you develop in Microsoft Visual Studio, you could either generate a Visual Studio solution using a CMake generator, or open the CMake project directly in Visual Studio.
|
||||
|
||||
### Translating Make commands to CMake
|
||||
|
||||
With the removal of GNU Make support, all build, test, and installation operations must now be performed using CMake.
|
||||
This section provides a quick reference for translating common `make` commands into their CMake equivalents.
|
||||
|
||||
#### Basic build workflow
|
||||
|
||||
Run `cmake -S . -B build` once before building to configure the build and generate native build files (e.g., Makefiles) in the `build` directory.
|
||||
This sets up an out-of-tree build, which is recommended.
|
||||
|
||||
| Make command | CMake equivalent | Description |
|
||||
|----------------|------------------------------------------------|--------------------------------------------------------------------|
|
||||
| `make` | `cmake --build build` | Build the libraries, programs, and tests in the `build` directory. |
|
||||
| `make test` | `ctest --test-dir build` | Run the tests produced by the previous build. |
|
||||
| `make clean` | `cmake --build build --target clean` | Remove build artifacts produced by the previous build. |
|
||||
| `make install` | `cmake --install build --prefix build/install` | Install the built libraries, headers, and tests to `build/install`. |
|
||||
|
||||
#### Building specific targets
|
||||
|
||||
Unless otherwise specified, the CMake command in the table below should be preceded by a `cmake -S . -B build` call to configure the build and generate build files in the `build` directory.
|
||||
|
||||
| Make command | CMake equivalent | Description |
|
||||
|-----------------|---------------------------------------------------------------------|---------------------------|
|
||||
| `make lib` | `cmake --build build --target lib` | Build only the libraries. |
|
||||
| `make tests` | `cmake -S . -B build -DENABLE_PROGRAMS=Off && cmake --build build` | Build test suites. |
|
||||
| `make programs` | `cmake --build build --target programs` | Build example programs. |
|
||||
| `make apidoc` | `cmake --build build --target mbedtls-apidoc` | Build documentation. |
|
||||
|
||||
Target names may differ slightly; use `cmake --build build --target help` to list all available CMake targets.
|
||||
|
||||
There is no CMake equivalent for `make generated_files` or `make neat`.
|
||||
Generated files are automatically created in the build tree with `cmake --build build` and removed with `cmake --build build --target clean`.
|
||||
If you need to build the generated files in the source tree without involving CMake, you can call `framework/scripts/make_generated_files.py`.
|
||||
|
||||
There is currently no equivalent for `make uninstall` in the Mbed TLS CMake build system.
|
||||
|
||||
#### Common build options
|
||||
|
||||
The following table illustrates the approximate CMake equivalents of common make commands.
|
||||
Most CMake examples show only the configuration step, others (like installation) correspond to different stages of the build process.
|
||||
|
||||
| Make usage | CMake usage | Description |
|
||||
|----------------------------|-------------------------------------------------------|----------------------|
|
||||
| `make DEBUG=1` | `cmake -S . -B build -DCMAKE_BUILD_TYPE=Debug` | Build in debug mode. |
|
||||
| `make SHARED=1` | `cmake -S . -B build -DUSE_SHARED_MBEDTLS_LIBRARY=On` | Also build shared libraries. |
|
||||
| `make GEN_FILES=""` | `cmake -S . -B build -DGEN_FILES=OFF` | Skip generating files (not a strict equivalent). |
|
||||
| `make DESTDIR=install_dir` | `cmake --install build --prefix install_dir` | Specify installation path. |
|
||||
| `make CC=clang` | `cmake -S . -B build -DCMAKE_C_COMPILER=clang` | Set the compiler. |
|
||||
| `make CFLAGS='-O2 -Wall'` | `cmake -S . -B build -DCMAKE_C_FLAGS="-O2 -Wall"` | Set compiler flags. |
|
||||
|
||||
## Repository split
|
||||
In Mbed TLS 4.0, the project was split into two repositories:
|
||||
- [Mbed TLS](https://github.com/Mbed-TLS/mbedtls): provides TLS and X.509 functionality.
|
||||
- [TF-PSA-Crypto](https://github.com/Mbed-TLS/TF-PSA-Crypto): provides the standalone cryptography library, implementing the PSA Cryptography API.
|
||||
Mbed TLS consumes TF-PSA-Crypto as a submodule.
|
||||
You should stay with Mbed TLS if you use TLS or X.509 functionality. You still have direct access to the cryptography library.
|
||||
|
||||
### File and directory relocations
|
||||
|
||||
The following table summarizes the file and directory relocations resulting from the repository split between Mbed TLS and TF-PSA-Crypto.
|
||||
These changes reflect the move of cryptographic, cryptographic-adjacent, and platform components from Mbed TLS into the new TF-PSA-Crypto repository.
|
||||
|
||||
| Original location | New location(s) | Notes |
|
||||
|-----------------------------------------|--------------------------------------------------------------------------------------|-------|
|
||||
| `library/*` (<sup>†</sup>) | `tf-psa-crypto/core/`<br>`tf-psa-crypto/drivers/builtin/src/` | Contains cryptographic, cryptographic-adjacent (e.g., ASN.1, Base64), and platform C modules and headers. |
|
||||
| `include/mbedtls/*` (<sup>†</sup>) | `tf-psa-crypto/include/mbedtls/`<br>`tf-psa-crypto/drivers/builtin/include/private/` | Public headers moved to `include/mbedtls`; now internal headers moved to `include/private`. |
|
||||
| `include/psa` | `tf-psa-crypto/include/psa` | All PSA headers consolidated here. |
|
||||
| `3rdparty/everest`<br>`3rdparty/p256-m` | `tf-psa-crypto/drivers/everest`<br>`tf-psa-crypto/drivers/p256-m` | Third-party crypto driver implementations. |
|
||||
|
||||
(<sup>†</sup>) The `library` and `include/mbedtls` directories still exist in Mbed TLS, but now contain only TLS and X.509 components.
|
||||
|
||||
### Configuration file split
|
||||
Cryptography and platform configuration options have been moved from `include/mbedtls/mbedtls_config.h` to `tf-psa-crypto/include/psa/crypto_config.h`, which is now mandatory.
|
||||
See [Compile-time configuration](#compile-time-configuration).
|
||||
|
||||
The header `include/mbedtls/mbedtls_config.h` still exists and now contains only the TLS and X.509 configuration options.
|
||||
|
||||
If you use the Python script `scripts/config.py` to adjust your configuration, you do not need to modify your scripts to specify which configuration file to edit, the script automatically updates the correct file.
|
||||
|
||||
There have been significant changes in the configuration options, primarily affecting cryptography.
|
||||
|
||||
#### Cryptography configuration
|
||||
- See [psa-transition.md](https://github.com/Mbed-TLS/TF-PSA-Crypto/blob/development/docs/psa-transition.md#compile-time-configuration).
|
||||
- See also the following sections in the TF-PSA-Crypto 1.0 migration guide:
|
||||
- *PSA as the Only Cryptography API* and its sub-section *Impact on the Library Configuration*
|
||||
- *Random Number Generation Configuration*
|
||||
|
||||
#### TLS configuration
|
||||
For details about TLS-related changes, see [Changes to TLS options](#changes-to-tls-options).
|
||||
|
||||
### Impact on some usages of the library
|
||||
|
||||
#### Checking out a branch or a tag
|
||||
After checking out a branch or tag of the Mbed TLS repository, you must now recursively update the submodules, as TF-PSA-Crypto contains itself a nested submodule:
|
||||
```
|
||||
git submodule update --init --recursive
|
||||
```
|
||||
|
||||
#### Linking directly to a built library
|
||||
|
||||
The Mbed TLS CMake build system still provides the cryptography libraries under their legacy name, `libmbedcrypto.<ext>`, so you can continue linking against them.
|
||||
These libraries are still located in the `library` directory within the build tree.
|
||||
|
||||
The cryptography libraries are also now provided as `libtfpsacrypto.<ext>`, consistent with the naming used in the TF-PSA-Crypto repository.
|
||||
|
||||
You may need to update include paths to the public header files, see [File and Directory Relocations](#file-and-directory-relocations) for details.
|
||||
|
||||
#### Using Mbed TLS as a CMake subproject
|
||||
|
||||
The base name of the libraries are now `tfpsacrypto` (formely `mbedcrypto`), `mbedx509` and `mbedtls`.
|
||||
As before, these base names are also the names of CMake targets to build each library.
|
||||
If your CMake scripts reference a cryptography library target, you need to update its name accordingly.
|
||||
|
||||
For example, the following CMake code:
|
||||
```
|
||||
target_link_libraries(mytarget PRIVATE mbedcrypto)
|
||||
```
|
||||
should be updated to:
|
||||
```
|
||||
target_link_libraries(mytarget PRIVATE tfpsacrypto)
|
||||
```
|
||||
|
||||
You can refer to the following example demonstrating how to consume Mbed TLS as a CMake subproject:
|
||||
- `programs/test/cmake_subproject`
|
||||
|
||||
#### Using Mbed TLS as a CMake package
|
||||
|
||||
The same renaming applies to the cryptography library targets declared as part of the Mbed TLS CMake package, use `MbedTLS::tfpsacrypto` instead of `MbedTLS::mbedcrypto`.
|
||||
|
||||
For example, the following CMake code:
|
||||
```
|
||||
find_package(MbedTLS REQUIRED)
|
||||
target_link_libraries(myapp PRIVATE MbedTLS::mbedcrypto)
|
||||
```
|
||||
should be updated to:
|
||||
```
|
||||
find_package(MbedTLS REQUIRED)
|
||||
target_link_libraries(myapp PRIVATE MbedTLS::tfpsacrypto)
|
||||
```
|
||||
You can also refer to the following example programs demonstrating how to consume Mbed TLS as a CMake package:
|
||||
- `programs/test/cmake_package`
|
||||
- `programs/test/cmake_package_install`
|
||||
|
||||
#### Using the Mbed TLS Crypto pkg-config file
|
||||
|
||||
The Mbed TLS CMake build system still provides the pkg-config file mbedcrypto.pc, so you can continue using it.
|
||||
Internally, it now references the tfpsacrypto library.
|
||||
|
||||
A new pkg-config file, `tfpsacrypto.pc`, is also provided.
|
||||
Both `mbedcrypto.pc` and `tfpsacrypto.pc` are functionally equivalent, providing the same compiler and linker flags.
|
||||
|
||||
#### Using Mbed TLS as an installed library
|
||||
|
||||
The Mbed TLS CMake build system still installs the cryptography libraries under their legacy name, `libmbedcrypto.<ext>`, so you can continue linking against them.
|
||||
The cryptography library is also now provided as `libtfpsacrypto.<ext>`.
|
||||
|
||||
Regarding the headers, the main change is the relocation of some headers to subdirectories called `private`.
|
||||
These headers are installed primarily to satisfy compiler dependencies.
|
||||
Others remain for historical reasons and may be cleaned up in later versions of the library.
|
||||
|
||||
We strongly recommend not relying on the declarations in these headers, as they may be removed or modified without notice.
|
||||
See the section Private Declarations in the TF-PSA-Crypto 1.0 migration guide for more information.
|
||||
|
||||
Finally, note the new `include/tf-psa-crypto` directory, which contains the TF-PSA-Crypto version and build-time configuration headers.
|
||||
|
||||
### Audience-Specific Notes
|
||||
|
||||
#### Application Developers using a distribution package
|
||||
- See [Impact on usages of the library](#impact-on-some-usages-of-the-library) for the possible impacts on:
|
||||
- Linking against the cryptography library or CMake targets.
|
||||
- Using the Mbed TLS Crypto pkg-config file.
|
||||
- Using Mbed TLS as an installed library
|
||||
|
||||
### Developer or package maintainers
|
||||
If you build or distribute Mbed TLS:
|
||||
- The build system is now CMake only, Makefiles and Visual Studio projects are removed.
|
||||
- You may need to adapt packaging scripts to handle the TF-PSA-Crypto submodule.
|
||||
- You should update submodules recursively after checkout.
|
||||
- Review [File and directory relocations](#file-and-directory-relocations) for updated paths.
|
||||
- See [Impact on usages of the library](#impact-on-some-usages-of-the-library) for the possible impacts on:
|
||||
- Linking against the cryptography library or CMake targets.
|
||||
- Using the Mbed TLS Crypto pkg-config file (`mbedcrypto.pc` or `tfpsacrypto.pc`).
|
||||
- Using Mbed TLS as an installed library
|
||||
- Configuration note: cryptography and platform options are now in `crypto_config.h` (see [Configuration file split](#configuration-file-split)).
|
||||
|
||||
### Platform Integrators
|
||||
If you integrate Mbed TLS with a platform or hardware drivers:
|
||||
- TF-PSA-Crypto is now a submodule, update integration scripts to initialize submodules recursively.
|
||||
- The PSA driver wrapper is now generated in TF-PSA-Crypto.
|
||||
- Platform-specific configuration are now handled in `crypto_config.h`.
|
||||
- See [Repository split](#repository-split) for how platform components moved to TF-PSA-Crypto.
|
||||
|
||||
## Compile-time configuration
|
||||
|
||||
### Configuration file split
|
||||
|
||||
All configuration options that are relevant to TF-PSA-Crypto must now be configured in one of its configuration files, namely:
|
||||
|
||||
* `TF_PSA_CRYPTO_CONFIG_FILE`, if set on the preprocessor command line;
|
||||
* otherwise `<psa/crypto_config.h>`;
|
||||
* additionally `TF_PSA_CRYPTO_USER_CONFIG_FILE`, if set.
|
||||
|
||||
Configuration options that are relevant to X.509 or TLS should still be set in the Mbed TLS configuration file (`MBEDTLS_CONFIG_FILE` or `<mbedtls/mbedtls_config.h>`, plus `MBEDTLS_USER_CONFIG_FILE` if it is set). However, you can define all options in the crypto configuration, and Mbed TLS will pick them up.
|
||||
|
||||
Generally speaking, the options that must be configured in TF-PSA-Crypto are:
|
||||
|
||||
* options related to platform settings;
|
||||
* options related to the choice of cryptographic mechanisms included in the build;
|
||||
* options related to the inner workings of cryptographic mechanisms, such as size/memory/performance compromises;
|
||||
* options related to crypto-adjacent features, such as ASN.1 and Base64.
|
||||
|
||||
See `include/psa/crypto_config.h` in TF-PSA-Crypto and `include/mbedtls/mbedtls_config.h` in Mbed TLS for details.
|
||||
|
||||
Notably, `<psa/crypto_config.h>` is no longer limited to `PSA_WANT_xxx` options.
|
||||
|
||||
Note that many options related to cryptography have changed; see the TF-PSA-Crypto migration guide for details.
|
||||
|
||||
### Split of `build_info.h` and `version.h`
|
||||
|
||||
The header file `<mbedtls/build_info.h>`, which includes the configuration file and provides the adjusted configuration macros, now has an similar file `<tf-psa-crypto/build_info.h>` in TF-PSA-Crypto. The Mbed TLS header includes the TF-PSA-Crypto header, so including `<mbedtls/build_info.h>` remains sufficient to obtain information about the crypto configuration.
|
||||
|
||||
TF-PSA-Crypto exposes its version through `<tf-psa-crypto/version.h>`, similar to `<mbedtls/version.h>` in Mbed TLS.
|
||||
|
||||
### Removal of `check_config.h`
|
||||
|
||||
The header `mbedtls/check_config.h` is no longer present. Including it from user configuration files was already obsolete in Mbed TLS 3.x, since it enforces properties the configuration as adjusted by `mbedtls/build_info.h`, not properties that the user configuration is expected to meet.
|
||||
|
||||
### Changes to TLS options
|
||||
|
||||
#### Enabling null cipher suites
|
||||
|
||||
The option to enable null cipher suites in TLS 1.2 has been renamed from `MBEDTLS_CIPHER_NULL_CIPHER` to `MBEDTLS_SSL_NULL_CIPHERSUITES`. It remains disabled in the default configuration.
|
||||
|
||||
#### Removal of backward compatibility options
|
||||
|
||||
The option `MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT` has been removed. Only the version standardized in RFC 9146 is supported now.
|
||||
|
||||
## PSA as the only cryptography API
|
||||
|
||||
The PSA API is now the only API for cryptographic primitives.
|
||||
|
||||
### Impact on application code
|
||||
|
||||
The X.509, PKCS7 and SSL modules always use PSA for cryptography, with a few exceptions documented in the [PSA limitations](architecture/psa-migration/psa-limitations.md) document. (These limitations are mostly transparent unless you want to leverage PSA accelerator drivers.) This corresponds to the behavior of Mbed TLS 3.x when `MBEDTLS_USE_PSA_CRYPTO` is enabled. In effect, `MBEDTLS_USE_PSA_CRYPTO` is now always enabled.
|
||||
|
||||
`psa_crypto_init()` must be called before performing any cryptographic operation, including indirect requests such as parsing a key or certificate or starting a TLS handshake.
|
||||
|
||||
A few functions take different parameters to migrate them to the PSA API. See “[Function prototype changes](#function-prototype-changes)”.
|
||||
|
||||
### No random generator instantiation
|
||||
|
||||
Formerly, applications using TLS, asymmetric cryptography operations involving a private key, or other features needing random numbers, needed to provide a random generator, generally by instantiating an entropy context (`mbedtls_entropy_context`) and a DRBG context (`mbedtls_ctr_drbg_context` or `mbedtls_hmac_drbg_context`). This is no longer necessary, or possible. All features that require a random generator (RNG) now use the one provided by the PSA subsystem.
|
||||
|
||||
Instead, applications that use random generators or keys (even public keys) need to call `psa_crypto_init()` before any cryptographic operation or key management operation.
|
||||
|
||||
See also [function prototype changes](#function-prototype-changes), many of which are related to the move from RNG callbacks to a global RNG.
|
||||
|
||||
### Impact on the library configuration
|
||||
|
||||
Mbed TLS follows the configuration of TF-PSA-Crypto with respect to cryptographic mechanisms. They are now based on `PSA_WANT_xxx` macros instead of legacy configuration macros such as `MBEDTLS_RSA_C`, `MBEDTLS_PKCS1_V15`, etc. The configuration of X.509 and TLS is not directly affected by the configuration. However, applications and middleware that rely on these configuration symbols to know which cryptographic mechanisms to support will need to migrate to `PSA_WANT_xxx` macros. For more information, consult the PSA transition guide in TF-PSA-Crypto.
|
||||
|
||||
## Private declarations
|
||||
|
||||
Since Mbed TLS 3.0, some things that are declared in a public header are not part of the stable application programming interface (API), but instead are considered private. Private elements may be removed or may have their semantics changed in a future minor release without notice.
|
||||
|
||||
### Understanding private declarations in public headers
|
||||
|
||||
In Mbed TLS 4.x, private elements in header files include:
|
||||
|
||||
* Anything appearing in a header file whose path contains `/private` (unless re-exported and documented in another non-private header).
|
||||
* Structure and union fields declared with `MBEDTLS_PRIVATE(field_name)` in the source code, and appearing as `private_field_name` in the rendered documentation. (This was already the case since Mbed TLS 3.0.)
|
||||
* Any preprocessor macro that is not documented with a Doxygen comment.
|
||||
In the source code, Doxygen comments start with `/**` or `/*!`. If a macro only has a comment above that starts with `/*`, the macro is considered private.
|
||||
In the rendered documentation, private macros appear with only an automatically rendered parameter list, value and location, but no custom text.
|
||||
* Any declaration that is guarded by the preprocessor macro `MBEDTLS_DECLARE_PRIVATE_IDENTIFIERS`.
|
||||
|
||||
### Usage of private declarations
|
||||
|
||||
Some private declarations are present in public headers for technical reasons, because they need to be visible to the compiler. Others are present for historical reasons and may be cleaned up in later versions of the library. We strongly recommend against relying on these declarations, since they may be removed or may have their semantics changed without notice.
|
||||
|
||||
Note that Mbed TLS 4.0 still relies on some private interfaces of TF-PSA-Crypto 1.0. We expect to remove this reliance gradually in future minor releases.
|
||||
|
||||
Sample programs have not been fully updated yet and some of them might still
|
||||
use APIs that are no longer public. You can recognize them by the fact that they
|
||||
define the macro `MBEDTLS_DECLARE_PRIVATE_IDENTIFIERS` (or
|
||||
`MBEDTLS_ALLOW_PRIVATE_ACCESS`) at the very top (before including headers). When
|
||||
you see one of these two macros in a sample program, be aware it has not been
|
||||
updated and parts of it do not demonstrate current practice.
|
||||
|
||||
We strongly recommend against defining `MBEDTLS_DECLARE_PRIVATE_IDENTIFIERS` or
|
||||
`MBEDTLS_ALLOW_PRIVATE_ACCESS` in your own application. If you do so, your code
|
||||
may not compile or work with future minor releases. If there's something you
|
||||
want to do that you feel can only be achieved by using one of these two macros,
|
||||
please reach out on github or the mailing list.
|
||||
|
||||
## Error codes
|
||||
|
||||
### Unified error code space
|
||||
|
||||
The convention still applies that functions return 0 for success and a negative value between -32767 and -1 on error. PSA functions (`psa_xxx()` or `mbedtls_psa_xxx()`) still return a `PSA_ERROR_xxx` error codes. Non-PSA functions (`mbedtls_xxx()` excluding `mbedtls_psa_xxx()`) can return either `PSA_ERROR_xxx` or `MBEDTLS_ERR_xxx` error codes.
|
||||
|
||||
There may be cases where an `MBEDTLS_ERR_xxx` constant has the same numerical value as a `PSA_ERROR_xxx`. In such cases, they have the same meaning: they are different names for the same error condition.
|
||||
|
||||
### Simplified legacy error codes
|
||||
|
||||
All values returned by a function to indicate an error now have a defined constant named `MBEDTLS_ERR_xxx` or `PSA_ERROR_xxx`. Functions no longer return the sum of a “low-level” and a “high-level” error code.
|
||||
|
||||
Generally, functions that used to return the sum of two error codes now return the low-level code. However, as before, the exact error code returned in a given scenario can change without notice unless the condition is specifically described in the function's documentation and no other condition is applicable.
|
||||
|
||||
As a consequence, the functions `mbedtls_low_level_strerr()` and `mbedtls_high_level_strerr()` no longer exist.
|
||||
|
||||
### Removed error code names
|
||||
|
||||
Many legacy error codes have been removed in favor of PSA error codes. Generally, functions that returned a legacy error code in the table below in Mbed TLS 3.6 now return the PSA error code listed on the same row. Similarly, callbacks should apply the same changes to error code, unless there has been a relevant change to the callback's interface.
|
||||
|
||||
| Legacy constant (Mbed TLS 3.6) | PSA constant (Mbed TLS 4.0) |
|
||||
|-----------------------------------------|---------------------------------|
|
||||
| `MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED` | `PSA_ERROR_CORRUPTION_DETECTED` |
|
||||
| `MBEDTLS_ERR_ERROR_GENERIC_ERROR` | `PSA_ERROR_GENERIC_ERROR` |
|
||||
| `MBEDTLS_ERR_NET_BUFFER_TOO_SMALL` | `PSA_ERROR_BUFFER_TOO_SMALL` |
|
||||
| `MBEDTLS_ERR_OID_BUF_TOO_SMALL` | `PSA_ERROR_BUFFER_TOO_SMALL` |
|
||||
| `MBEDTLS_ERR_OID_NOT_FOUND` | `PSA_ERROR_NOT_SUPPORTED` |
|
||||
| `MBEDTLS_ERR_PKCS7_ALLOC_FAILED` | `PSA_ERROR_INSUFFICIENT_MEMORY` |
|
||||
| `MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA` | `PSA_ERROR_INVALID_ARGUMENT` |
|
||||
| `MBEDTLS_ERR_PKCS7_VERIFY_FAIL` | `PSA_ERROR_INVALID_SIGNATURE` |
|
||||
| `MBEDTLS_ERR_SSL_ALLOC_FAILED` | `PSA_ERROR_INSUFFICIENT_MEMORY` |
|
||||
| `MBEDTLS_ERR_SSL_BAD_INPUT_DATA` | `PSA_ERROR_INVALID_ARGUMENT` |
|
||||
| `MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL` | `PSA_ERROR_BUFFER_TOO_SMALL` |
|
||||
| `MBEDTLS_ERR_X509_ALLOC_FAILED` | `PSA_ERROR_INSUFFICIENT_MEMORY` |
|
||||
| `MBEDTLS_ERR_X509_BUFFER_TOO_SMALL` | `PSA_ERROR_BUFFER_TOO_SMALL` |
|
||||
|
||||
See also the corresponding section in the TF-PSA-Crypto migration guide, which lists error codes from cryptography modules.
|
||||
|
||||
## Removal of deprecated functions
|
||||
|
||||
### Removal of deprecated X.509 functions
|
||||
|
||||
The deprecated function `mbedtls_x509write_crt_set_serial()` has been removed. The function was superseded by `mbedtls_x509write_crt_set_serial_raw()`.
|
||||
|
||||
### Removal of deprecated SSL functions
|
||||
|
||||
The deprecated function `mbedtls_ssl_conf_curves()` has been removed.
|
||||
The function was superseded by `mbedtls_ssl_conf_groups()`.
|
||||
|
||||
### Removal of `compat-2.x.h`
|
||||
|
||||
The header `compat-2.x.h`, containing some definitions for backward compatibility with Mbed TLS 2.x, has been removed.
|
||||
|
||||
## Removed features
|
||||
|
||||
### Removal of obsolete key exchanges methods in (D)TLS 1.2
|
||||
|
||||
Mbed TLS 4.0 no longer supports key exchange methods that rely on finite-field Diffie-Hellman (DHE) in TLS 1.2 and DTLS 1.2. (Only ephemeral Diffie-Hellman was ever supported, Mbed TLS 3.x already did not support static Diffie-Hellman.) Finite-field Diffie-Hellman remains supported in TLS 1.3.
|
||||
|
||||
Mbed TLS 4.0 no longer supports key exchange methods that rely on RSA decryption (without forward secrecy). RSA signatures remain supported. This affects TLS 1.2 and DTLS 1.2 (TLS 1.3 does not have key exchanges using RSA decryption).
|
||||
|
||||
That is, the following key exchange types are no longer supported:
|
||||
|
||||
* RSA-PSK;
|
||||
* RSA (i.e. cipher suites using only RSA decryption: cipher suites using RSA signatures remain supported);
|
||||
* DHE-PSK (except in TLS 1.3);
|
||||
* DHE-RSA (except in TLS 1.3).
|
||||
* static ECDH (ECDH-RSA and ECDH-ECDSA, as opposed to ephemeral ECDH (ECDHE) which remains supported).
|
||||
|
||||
The full list of removed cipher suites is:
|
||||
|
||||
```
|
||||
TLS-DHE-PSK-WITH-AES-128-CBC-SHA
|
||||
TLS-DHE-PSK-WITH-AES-128-CBC-SHA256
|
||||
TLS-DHE-PSK-WITH-AES-128-CCM
|
||||
TLS-DHE-PSK-WITH-AES-128-CCM-8
|
||||
TLS-DHE-PSK-WITH-AES-128-GCM-SHA256
|
||||
TLS-DHE-PSK-WITH-AES-256-CBC-SHA
|
||||
TLS-DHE-PSK-WITH-AES-256-CBC-SHA384
|
||||
TLS-DHE-PSK-WITH-AES-256-CCM
|
||||
TLS-DHE-PSK-WITH-AES-256-CCM-8
|
||||
TLS-DHE-PSK-WITH-AES-256-GCM-SHA384
|
||||
TLS-DHE-PSK-WITH-ARIA-128-CBC-SHA256
|
||||
TLS-DHE-PSK-WITH-ARIA-128-GCM-SHA256
|
||||
TLS-DHE-PSK-WITH-ARIA-256-CBC-SHA384
|
||||
TLS-DHE-PSK-WITH-ARIA-256-GCM-SHA384
|
||||
TLS-DHE-PSK-WITH-CAMELLIA-128-CBC-SHA256
|
||||
TLS-DHE-PSK-WITH-CAMELLIA-128-GCM-SHA256
|
||||
TLS-DHE-PSK-WITH-CAMELLIA-256-CBC-SHA384
|
||||
TLS-DHE-PSK-WITH-CAMELLIA-256-GCM-SHA384
|
||||
TLS-DHE-PSK-WITH-CHACHA20-POLY1305-SHA256
|
||||
TLS-DHE-PSK-WITH-NULL-SHA
|
||||
TLS-DHE-PSK-WITH-NULL-SHA256
|
||||
TLS-DHE-PSK-WITH-NULL-SHA384
|
||||
TLS-DHE-RSA-WITH-AES-128-CBC-SHA
|
||||
TLS-DHE-RSA-WITH-AES-128-CBC-SHA256
|
||||
TLS-DHE-RSA-WITH-AES-128-CCM
|
||||
TLS-DHE-RSA-WITH-AES-128-CCM-8
|
||||
TLS-DHE-RSA-WITH-AES-128-GCM-SHA256
|
||||
TLS-DHE-RSA-WITH-AES-256-CBC-SHA
|
||||
TLS-DHE-RSA-WITH-AES-256-CBC-SHA256
|
||||
TLS-DHE-RSA-WITH-AES-256-CCM
|
||||
TLS-DHE-RSA-WITH-AES-256-CCM-8
|
||||
TLS-DHE-RSA-WITH-AES-256-GCM-SHA384
|
||||
TLS-DHE-RSA-WITH-ARIA-128-CBC-SHA256
|
||||
TLS-DHE-RSA-WITH-ARIA-128-GCM-SHA256
|
||||
TLS-DHE-RSA-WITH-ARIA-256-CBC-SHA384
|
||||
TLS-DHE-RSA-WITH-ARIA-256-GCM-SHA384
|
||||
TLS-DHE-RSA-WITH-CAMELLIA-128-CBC-SHA
|
||||
TLS-DHE-RSA-WITH-CAMELLIA-128-CBC-SHA256
|
||||
TLS-DHE-RSA-WITH-CAMELLIA-128-GCM-SHA256
|
||||
TLS-DHE-RSA-WITH-CAMELLIA-256-CBC-SHA
|
||||
TLS-DHE-RSA-WITH-CAMELLIA-256-CBC-SHA256
|
||||
TLS-DHE-RSA-WITH-CAMELLIA-256-GCM-SHA384
|
||||
TLS-DHE-RSA-WITH-CHACHA20-POLY1305-SHA256
|
||||
TLS-ECDH-ECDSA-WITH-AES-128-CBC-SHA
|
||||
TLS-ECDH-ECDSA-WITH-AES-128-CBC-SHA256
|
||||
TLS-ECDH-ECDSA-WITH-AES-128-GCM-SHA256
|
||||
TLS-ECDH-ECDSA-WITH-AES-256-CBC-SHA
|
||||
TLS-ECDH-ECDSA-WITH-AES-256-CBC-SHA384
|
||||
TLS-ECDH-ECDSA-WITH-AES-256-GCM-SHA384
|
||||
TLS-ECDH-ECDSA-WITH-ARIA-128-CBC-SHA256
|
||||
TLS-ECDH-ECDSA-WITH-ARIA-128-GCM-SHA256
|
||||
TLS-ECDH-ECDSA-WITH-ARIA-256-CBC-SHA384
|
||||
TLS-ECDH-ECDSA-WITH-ARIA-256-GCM-SHA384
|
||||
TLS-ECDH-ECDSA-WITH-CAMELLIA-128-CBC-SHA256
|
||||
TLS-ECDH-ECDSA-WITH-CAMELLIA-128-GCM-SHA256
|
||||
TLS-ECDH-ECDSA-WITH-CAMELLIA-256-CBC-SHA384
|
||||
TLS-ECDH-ECDSA-WITH-CAMELLIA-256-GCM-SHA384
|
||||
TLS-ECDH-ECDSA-WITH-NULL-SHA
|
||||
TLS-ECDH-RSA-WITH-AES-128-CBC-SHA
|
||||
TLS-ECDH-RSA-WITH-AES-128-CBC-SHA256
|
||||
TLS-ECDH-RSA-WITH-AES-128-GCM-SHA256
|
||||
TLS-ECDH-RSA-WITH-AES-256-CBC-SHA
|
||||
TLS-ECDH-RSA-WITH-AES-256-CBC-SHA384
|
||||
TLS-ECDH-RSA-WITH-AES-256-GCM-SHA384
|
||||
TLS-ECDH-RSA-WITH-ARIA-128-CBC-SHA256
|
||||
TLS-ECDH-RSA-WITH-ARIA-128-GCM-SHA256
|
||||
TLS-ECDH-RSA-WITH-ARIA-256-CBC-SHA384
|
||||
TLS-ECDH-RSA-WITH-ARIA-256-GCM-SHA384
|
||||
TLS-ECDH-RSA-WITH-CAMELLIA-128-CBC-SHA256
|
||||
TLS-ECDH-RSA-WITH-CAMELLIA-128-GCM-SHA256
|
||||
TLS-ECDH-RSA-WITH-CAMELLIA-256-CBC-SHA384
|
||||
TLS-ECDH-RSA-WITH-CAMELLIA-256-GCM-SHA384
|
||||
TLS-ECDH-RSA-WITH-NULL-SHA
|
||||
TLS-RSA-PSK-WITH-AES-128-CBC-SHA
|
||||
TLS-RSA-PSK-WITH-AES-128-CBC-SHA256
|
||||
TLS-RSA-PSK-WITH-AES-128-GCM-SHA256
|
||||
TLS-RSA-PSK-WITH-AES-256-CBC-SHA
|
||||
TLS-RSA-PSK-WITH-AES-256-CBC-SHA384
|
||||
TLS-RSA-PSK-WITH-AES-256-GCM-SHA384
|
||||
TLS-RSA-PSK-WITH-ARIA-128-CBC-SHA256
|
||||
TLS-RSA-PSK-WITH-ARIA-128-GCM-SHA256
|
||||
TLS-RSA-PSK-WITH-ARIA-256-CBC-SHA384
|
||||
TLS-RSA-PSK-WITH-ARIA-256-GCM-SHA384
|
||||
TLS-RSA-PSK-WITH-CAMELLIA-128-CBC-SHA256
|
||||
TLS-RSA-PSK-WITH-CAMELLIA-128-GCM-SHA256
|
||||
TLS-RSA-PSK-WITH-CAMELLIA-256-CBC-SHA384
|
||||
TLS-RSA-PSK-WITH-CAMELLIA-256-GCM-SHA384
|
||||
TLS-RSA-PSK-WITH-CHACHA20-POLY1305-SHA256
|
||||
TLS-RSA-PSK-WITH-NULL-SHA
|
||||
TLS-RSA-PSK-WITH-NULL-SHA256
|
||||
TLS-RSA-PSK-WITH-NULL-SHA384
|
||||
TLS-RSA-WITH-AES-128-CBC-SHA
|
||||
TLS-RSA-WITH-AES-128-CBC-SHA256
|
||||
TLS-RSA-WITH-AES-128-CCM
|
||||
TLS-RSA-WITH-AES-128-CCM-8
|
||||
TLS-RSA-WITH-AES-128-GCM-SHA256
|
||||
TLS-RSA-WITH-AES-256-CBC-SHA
|
||||
TLS-RSA-WITH-AES-256-CBC-SHA256
|
||||
TLS-RSA-WITH-AES-256-CCM
|
||||
TLS-RSA-WITH-AES-256-CCM-8
|
||||
TLS-RSA-WITH-AES-256-GCM-SHA384
|
||||
TLS-RSA-WITH-ARIA-128-CBC-SHA256
|
||||
TLS-RSA-WITH-ARIA-128-GCM-SHA256
|
||||
TLS-RSA-WITH-ARIA-256-CBC-SHA384
|
||||
TLS-RSA-WITH-ARIA-256-GCM-SHA384
|
||||
TLS-RSA-WITH-CAMELLIA-128-CBC-SHA
|
||||
TLS-RSA-WITH-CAMELLIA-128-CBC-SHA256
|
||||
TLS-RSA-WITH-CAMELLIA-128-GCM-SHA256
|
||||
TLS-RSA-WITH-CAMELLIA-256-CBC-SHA
|
||||
TLS-RSA-WITH-CAMELLIA-256-CBC-SHA256
|
||||
TLS-RSA-WITH-CAMELLIA-256-GCM-SHA384
|
||||
TLS-RSA-WITH-NULL-MD5
|
||||
TLS-RSA-WITH-NULL-SHA
|
||||
TLS-RSA-WITH-NULL-SHA256
|
||||
```
|
||||
|
||||
As a consequence of the removal of support for DHE in (D)TLS 1.2, the following functions are no longer useful and have been removed:
|
||||
|
||||
```
|
||||
mbedtls_ssl_conf_dh_param_bin()
|
||||
mbedtls_ssl_conf_dh_param_ctx()
|
||||
mbedtls_ssl_conf_dhm_min_bitlen()
|
||||
```
|
||||
|
||||
### Removal of elliptic curves
|
||||
|
||||
Following their removal from the crypto library, elliptic curves of less than 250 bits (secp192r1, secp192k1, secp224r1, secp224k1) are no longer supported in certificates and in TLS.
|
||||
|
||||
### Removal of deprecated functions
|
||||
|
||||
The deprecated functions `mbedtls_ssl_conf_min_version()` and `mbedtls_ssl_conf_max_version()`, and the associated constants `MBEDTLS_SSL_MAJOR_VERSION_3`, `MBEDTLS_SSL_MINOR_VERSION_3` and `MBEDTLS_SSL_MINOR_VERSION_4` have been removed. Use `mbedtls_ssl_conf_min_tls_version()` and `mbedtls_ssl_conf_max_tls_version()` with `MBEDTLS_SSL_VERSION_TLS1_2` or `MBEDTLS_SSL_VERSION_TLS1_3` instead.
|
||||
|
||||
The deprecated function `mbedtls_ssl_conf_sig_hashes()` has been removed. Use `mbedtls_ssl_conf_sig_algs()` instead.
|
||||
|
||||
## Function prototype changes
|
||||
|
||||
A number of existing functions now take a different list of arguments, mostly to migrate them to the PSA API.
|
||||
|
||||
### Public functions no longer take a RNG callback
|
||||
|
||||
Functions that need randomness no longer take an RNG callback in the form of `f_rng, p_rng` arguments. Instead, they use the PSA Crypto random generator (accessible as `psa_generate_random()`). All software using the X.509 or SSL modules must call `psa_crypto_init()` before calling any of the functions listed here.
|
||||
|
||||
### RNG removal in X.509
|
||||
|
||||
The following function prototypes have been changed in `mbedtls/x509_crt.h`:
|
||||
|
||||
```c
|
||||
int mbedtls_x509write_crt_der(mbedtls_x509write_cert *ctx, unsigned char *buf, size_t size,
|
||||
int (*f_rng)(void *, unsigned char *, size_t),
|
||||
void *p_rng);
|
||||
|
||||
int mbedtls_x509write_crt_pem(mbedtls_x509write_cert *ctx, unsigned char *buf, size_t size,
|
||||
int (*f_rng)(void *, unsigned char *, size_t),
|
||||
void *p_rng);
|
||||
```
|
||||
|
||||
to
|
||||
|
||||
```c
|
||||
int mbedtls_x509write_crt_der(mbedtls_x509write_cert *ctx, unsigned char *buf, size_t size);
|
||||
|
||||
int mbedtls_x509write_crt_pem(mbedtls_x509write_cert *ctx, unsigned char *buf, size_t size);
|
||||
```
|
||||
|
||||
The following function prototypes have been changed in `mbedtls/x509_csr.h`:
|
||||
```c
|
||||
int mbedtls_x509write_csr_der(mbedtls_x509write_csr *ctx, unsigned char *buf, size_t size,
|
||||
int (*f_rng)(void *, unsigned char *, size_t),
|
||||
void *p_rng);
|
||||
|
||||
int mbedtls_x509write_csr_pem(mbedtls_x509write_csr *ctx, unsigned char *buf, size_t size,
|
||||
int (*f_rng)(void *, unsigned char *, size_t),
|
||||
void *p_rng);
|
||||
```
|
||||
|
||||
to
|
||||
|
||||
```c
|
||||
int mbedtls_x509write_csr_der(mbedtls_x509write_csr *ctx, unsigned char *buf, size_t size);
|
||||
|
||||
int mbedtls_x509write_csr_pem(mbedtls_x509write_csr *ctx, unsigned char *buf, size_t size);
|
||||
```
|
||||
|
||||
### RNG removal in SSL
|
||||
|
||||
The following function prototype has been changed in `mbedtls/ssl_cookie.h`:
|
||||
|
||||
```c
|
||||
int mbedtls_ssl_cookie_setup(mbedtls_ssl_cookie_ctx *ctx,
|
||||
int (*f_rng)(void *, unsigned char *, size_t),
|
||||
void *p_rng);
|
||||
```
|
||||
|
||||
to
|
||||
|
||||
```c
|
||||
int mbedtls_ssl_cookie_setup(mbedtls_ssl_cookie_ctx *ctx);
|
||||
```
|
||||
|
||||
### Removal of `mbedtls_ssl_conf_rng`
|
||||
|
||||
`mbedtls_ssl_conf_rng()` has been removed from the library. Its sole purpose was to configure the RNG used for TLS, but now the PSA Crypto random generator is used throughout the library.
|
||||
|
||||
### Changes to mbedtls_ssl_ticket_setup
|
||||
|
||||
In the arguments of the function `mbedtls_ssl_ticket_setup()`, the `mbedtls_cipher_type_t` argument specifying the AEAD mechanism for ticket protection has been replaced by an equivalent PSA description consisting of a key type, a size and an algorithm. Also, the function no longer takes RNG arguments.
|
||||
|
||||
The prototype in `mbedtls/ssl_ticket.h` has changed from
|
||||
|
||||
```c
|
||||
int mbedtls_ssl_ticket_setup(mbedtls_ssl_ticket_context *ctx,
|
||||
mbedtls_f_rng_t *f_rng, void *p_rng,
|
||||
mbedtls_cipher_type_t cipher,
|
||||
uint32_t lifetime);
|
||||
```
|
||||
|
||||
to
|
||||
|
||||
```c
|
||||
int mbedtls_ssl_ticket_setup(mbedtls_ssl_ticket_context *ctx,
|
||||
psa_algorithm_t alg, psa_key_type_t key_type, psa_key_bits_t key_bits,
|
||||
uint32_t lifetime);
|
||||
```
|
||||
|
||||
## OID module
|
||||
|
||||
The compilation option `MBEDTLS_OID_C` no longer exists. OID tables are included in the build automatically as needed for parsing and writing X.509 data.
|
||||
|
||||
Mbed TLS no longer offers interfaces to look up values by OID or OID by enum values (`mbedtls_oid_get_<thing>()` and `mbedtls_oid_get_oid_by_<thing>()`).
|
||||
|
||||
The header `<mbedtls/oid.h>` now only provides functions to convert between binary and dotted string OID representations. These functions are now part of `libmbedx509` rather than the crypto library. The function `mbedtls_oid_get_numeric_string()` is guarded by `MBEDTLS_X509_USE_C`, and `mbedtls_oid_from_numeric_string()` by `MBEDTLS_X509_CREATE_C`. The header also still defines macros for OID strings that are relevant to X.509.
|
||||
@@ -1,44 +0,0 @@
|
||||
## Compile-time configuration
|
||||
|
||||
### Configuration file split
|
||||
|
||||
All configuration options that are relevant to TF-PSA-Crypto must now be configured in one of its configuration files, namely:
|
||||
|
||||
* `TF_PSA_CRYPTO_CONFIG_FILE`, if set on the preprocessor command line;
|
||||
* otherwise `<psa/crypto_config.h>`;
|
||||
* additionally `TF_PSA_CRYPTO_USER_CONFIG_FILE`, if set.
|
||||
|
||||
Configuration options that are relevant to X.509 or TLS should still be set in the Mbed TLS configuration file (`MBEDTLS_CONFIG_FILE` or `<mbedtls/mbedtls_config.h>`, plus `MBEDTLS_USER_CONFIG_FILE` if it is set). However, you can define all options in the crypto configuration, and Mbed TLS will pick them up.
|
||||
|
||||
Generally speaking, the options that must be configured in TF-PSA-Crypto are:
|
||||
|
||||
* options related to platform settings;
|
||||
* options related to the choice of cryptographic mechanisms included in the build;
|
||||
* options related to the inner workings of cryptographic mechanisms, such as size/memory/performance compromises;
|
||||
* options related to crypto-adjacent features, such as ASN.1 and Base64.
|
||||
|
||||
See `include/psa/crypto_config.h` in TF-PSA-Crypto and `include/mbedtls/mbedtls_config.h` in Mbed TLS for details.
|
||||
|
||||
Notably, `<psa/crypto_config.h>` is no longer limited to `PSA_WANT_xxx` options.
|
||||
|
||||
Note that many options related to cryptography have changed; see the TF-PSA-Crypto migration guide for details.
|
||||
|
||||
### Split of `build_info.h` and `version.h`
|
||||
|
||||
The header file `<mbedtls/build_info.h>`, which includes the configuration file and provides the adjusted configuration macros, now has an similar file `<tf-psa-crypto/build_info.h>` in TF-PSA-Crypto. The Mbed TLS header includes the TF-PSA-Crypto header, so including `<mbedtls/build_info.h>` remains sufficient to obtain information about the crypto configuration.
|
||||
|
||||
TF-PSA-Crypto exposes its version through `<tf-psa-crypto/version.h>`, similar to `<mbedtls/version.h>` in Mbed TLS.
|
||||
|
||||
### Removal of `check_config.h`
|
||||
|
||||
The header `mbedtls/check_config.h` is no longer present. Including it from user configuration files was already obsolete in Mbed TLS 3.x, since it enforces properties the configuration as adjusted by `mbedtls/build_info.h`, not properties that the user configuration is expected to meet.
|
||||
|
||||
### Changes to TLS options
|
||||
|
||||
#### Enabling null cipher suites
|
||||
|
||||
The option to enable null cipher suites in TLS 1.2 has been renamed from `MBEDTLS_CIPHER_NULL_CIPHER` to `MBEDTLS_SSL_NULL_CIPHERSUITES`. It remains disabled in the default configuration.
|
||||
|
||||
#### Removal of backward compatibility options
|
||||
|
||||
The option `MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT` has been removed. Only the version standardized in RFC 9146 is supported now.
|
||||
@@ -1,14 +0,0 @@
|
||||
## Removal of deprecated functions
|
||||
|
||||
### Removal of deprecated X.509 functions
|
||||
|
||||
The deprecated function `mbedtls_x509write_crt_set_serial()` has been removed. The function was superseded by `mbedtls_x509write_crt_set_serial_raw()`.
|
||||
|
||||
### Removal of deprecated SSL functions
|
||||
|
||||
The deprecated function `mbedtls_ssl_conf_curves()` has been removed.
|
||||
The function was superseded by `mbedtls_ssl_conf_groups()`.
|
||||
|
||||
### Removal of `compat-2.x.h`
|
||||
|
||||
The header `compat-2.x.h`, containing some definitions for backward compatibility with Mbed TLS 2.x, has been removed.
|
||||
@@ -1,37 +0,0 @@
|
||||
## Error codes
|
||||
|
||||
### Unified error code space
|
||||
|
||||
The convention still applies that functions return 0 for success and a negative value between -32767 and -1 on error. PSA functions (`psa_xxx()` or `mbedtls_psa_xxx()`) still return a `PSA_ERROR_xxx` error codes. Non-PSA functions (`mbedtls_xxx()` excluding `mbedtls_psa_xxx()`) can return either `PSA_ERROR_xxx` or `MBEDTLS_ERR_xxx` error codes.
|
||||
|
||||
There may be cases where an `MBEDTLS_ERR_xxx` constant has the same numerical value as a `PSA_ERROR_xxx`. In such cases, they have the same meaning: they are different names for the same error condition.
|
||||
|
||||
### Simplified legacy error codes
|
||||
|
||||
All values returned by a function to indicate an error now have a defined constant named `MBEDTLS_ERR_xxx` or `PSA_ERROR_xxx`. Functions no longer return the sum of a “low-level” and a “high-level” error code.
|
||||
|
||||
Generally, functions that used to return the sum of two error codes now return the low-level code. However, as before, the exact error code returned in a given scenario can change without notice unless the condition is specifically described in the function's documentation and no other condition is applicable.
|
||||
|
||||
As a consequence, the functions `mbedtls_low_level_strerr()` and `mbedtls_high_level_strerr()` no longer exist.
|
||||
|
||||
### Removed error code names
|
||||
|
||||
Many legacy error codes have been removed in favor of PSA error codes. Generally, functions that returned a legacy error code in the table below in Mbed TLS 3.6 now return the PSA error code listed on the same row. Similarly, callbacks should apply the same changes to error code, unless there has been a relevant change to the callback's interface.
|
||||
|
||||
| Legacy constant (Mbed TLS 3.6) | PSA constant (Mbed TLS 4.0) |
|
||||
|-----------------------------------------|---------------------------------|
|
||||
| `MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED` | `PSA_ERROR_CORRUPTION_DETECTED` |
|
||||
| `MBEDTLS_ERR_ERROR_GENERIC_ERROR` | `PSA_ERROR_GENERIC_ERROR` |
|
||||
| `MBEDTLS_ERR_NET_BUFFER_TOO_SMALL` | `PSA_ERROR_BUFFER_TOO_SMALL` |
|
||||
| `MBEDTLS_ERR_OID_BUF_TOO_SMALL` | `PSA_ERROR_BUFFER_TOO_SMALL` |
|
||||
| `MBEDTLS_ERR_OID_NOT_FOUND` | `PSA_ERROR_NOT_SUPPORTED` |
|
||||
| `MBEDTLS_ERR_PKCS7_ALLOC_FAILED` | `PSA_ERROR_INSUFFICIENT_MEMORY` |
|
||||
| `MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA` | `PSA_ERROR_INVALID_ARGUMENT` |
|
||||
| `MBEDTLS_ERR_PKCS7_VERIFY_FAIL` | `PSA_ERROR_INVALID_SIGNATURE` |
|
||||
| `MBEDTLS_ERR_SSL_ALLOC_FAILED` | `PSA_ERROR_INSUFFICIENT_MEMORY` |
|
||||
| `MBEDTLS_ERR_SSL_BAD_INPUT_DATA` | `PSA_ERROR_INVALID_ARGUMENT` |
|
||||
| `MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL` | `PSA_ERROR_BUFFER_TOO_SMALL` |
|
||||
| `MBEDTLS_ERR_X509_ALLOC_FAILED` | `PSA_ERROR_INSUFFICIENT_MEMORY` |
|
||||
| `MBEDTLS_ERR_X509_BUFFER_TOO_SMALL` | `PSA_ERROR_BUFFER_TOO_SMALL` |
|
||||
|
||||
See also the corresponding section in the TF-PSA-Crypto migration guide, which lists error codes from cryptography modules.
|
||||
@@ -1,152 +0,0 @@
|
||||
## Removed features
|
||||
|
||||
### Removal of obsolete key exchanges methods in (D)TLS 1.2
|
||||
|
||||
Mbed TLS 4.0 no longer supports key exchange methods that rely on finite-field Diffie-Hellman (DHE) in TLS 1.2 and DTLS 1.2. (Only ephemeral Diffie-Hellman was ever supported, Mbed TLS 3.x already did not support static Diffie-Hellman.) Finite-field Diffie-Hellman remains supported in TLS 1.3.
|
||||
|
||||
Mbed TLS 4.0 no longer supports key exchange methods that rely on RSA decryption (without forward secrecy). RSA signatures remain supported. This affects TLS 1.2 and DTLS 1.2 (TLS 1.3 does not have key exchanges using RSA decryption).
|
||||
|
||||
That is, the following key exchange types are no longer supported:
|
||||
|
||||
* RSA-PSK;
|
||||
* RSA (i.e. cipher suites using only RSA decryption: cipher suites using RSA signatures remain supported);
|
||||
* DHE-PSK (except in TLS 1.3);
|
||||
* DHE-RSA (except in TLS 1.3).
|
||||
* static ECDH (ECDH-RSA and ECDH-ECDSA, as opposed to ephemeral ECDH (ECDHE) which remains supported).
|
||||
|
||||
The full list of removed cipher suites is:
|
||||
|
||||
```
|
||||
TLS-DHE-PSK-WITH-AES-128-CBC-SHA
|
||||
TLS-DHE-PSK-WITH-AES-128-CBC-SHA256
|
||||
TLS-DHE-PSK-WITH-AES-128-CCM
|
||||
TLS-DHE-PSK-WITH-AES-128-CCM-8
|
||||
TLS-DHE-PSK-WITH-AES-128-GCM-SHA256
|
||||
TLS-DHE-PSK-WITH-AES-256-CBC-SHA
|
||||
TLS-DHE-PSK-WITH-AES-256-CBC-SHA384
|
||||
TLS-DHE-PSK-WITH-AES-256-CCM
|
||||
TLS-DHE-PSK-WITH-AES-256-CCM-8
|
||||
TLS-DHE-PSK-WITH-AES-256-GCM-SHA384
|
||||
TLS-DHE-PSK-WITH-ARIA-128-CBC-SHA256
|
||||
TLS-DHE-PSK-WITH-ARIA-128-GCM-SHA256
|
||||
TLS-DHE-PSK-WITH-ARIA-256-CBC-SHA384
|
||||
TLS-DHE-PSK-WITH-ARIA-256-GCM-SHA384
|
||||
TLS-DHE-PSK-WITH-CAMELLIA-128-CBC-SHA256
|
||||
TLS-DHE-PSK-WITH-CAMELLIA-128-GCM-SHA256
|
||||
TLS-DHE-PSK-WITH-CAMELLIA-256-CBC-SHA384
|
||||
TLS-DHE-PSK-WITH-CAMELLIA-256-GCM-SHA384
|
||||
TLS-DHE-PSK-WITH-CHACHA20-POLY1305-SHA256
|
||||
TLS-DHE-PSK-WITH-NULL-SHA
|
||||
TLS-DHE-PSK-WITH-NULL-SHA256
|
||||
TLS-DHE-PSK-WITH-NULL-SHA384
|
||||
TLS-DHE-RSA-WITH-AES-128-CBC-SHA
|
||||
TLS-DHE-RSA-WITH-AES-128-CBC-SHA256
|
||||
TLS-DHE-RSA-WITH-AES-128-CCM
|
||||
TLS-DHE-RSA-WITH-AES-128-CCM-8
|
||||
TLS-DHE-RSA-WITH-AES-128-GCM-SHA256
|
||||
TLS-DHE-RSA-WITH-AES-256-CBC-SHA
|
||||
TLS-DHE-RSA-WITH-AES-256-CBC-SHA256
|
||||
TLS-DHE-RSA-WITH-AES-256-CCM
|
||||
TLS-DHE-RSA-WITH-AES-256-CCM-8
|
||||
TLS-DHE-RSA-WITH-AES-256-GCM-SHA384
|
||||
TLS-DHE-RSA-WITH-ARIA-128-CBC-SHA256
|
||||
TLS-DHE-RSA-WITH-ARIA-128-GCM-SHA256
|
||||
TLS-DHE-RSA-WITH-ARIA-256-CBC-SHA384
|
||||
TLS-DHE-RSA-WITH-ARIA-256-GCM-SHA384
|
||||
TLS-DHE-RSA-WITH-CAMELLIA-128-CBC-SHA
|
||||
TLS-DHE-RSA-WITH-CAMELLIA-128-CBC-SHA256
|
||||
TLS-DHE-RSA-WITH-CAMELLIA-128-GCM-SHA256
|
||||
TLS-DHE-RSA-WITH-CAMELLIA-256-CBC-SHA
|
||||
TLS-DHE-RSA-WITH-CAMELLIA-256-CBC-SHA256
|
||||
TLS-DHE-RSA-WITH-CAMELLIA-256-GCM-SHA384
|
||||
TLS-DHE-RSA-WITH-CHACHA20-POLY1305-SHA256
|
||||
TLS-ECDH-ECDSA-WITH-AES-128-CBC-SHA
|
||||
TLS-ECDH-ECDSA-WITH-AES-128-CBC-SHA256
|
||||
TLS-ECDH-ECDSA-WITH-AES-128-GCM-SHA256
|
||||
TLS-ECDH-ECDSA-WITH-AES-256-CBC-SHA
|
||||
TLS-ECDH-ECDSA-WITH-AES-256-CBC-SHA384
|
||||
TLS-ECDH-ECDSA-WITH-AES-256-GCM-SHA384
|
||||
TLS-ECDH-ECDSA-WITH-ARIA-128-CBC-SHA256
|
||||
TLS-ECDH-ECDSA-WITH-ARIA-128-GCM-SHA256
|
||||
TLS-ECDH-ECDSA-WITH-ARIA-256-CBC-SHA384
|
||||
TLS-ECDH-ECDSA-WITH-ARIA-256-GCM-SHA384
|
||||
TLS-ECDH-ECDSA-WITH-CAMELLIA-128-CBC-SHA256
|
||||
TLS-ECDH-ECDSA-WITH-CAMELLIA-128-GCM-SHA256
|
||||
TLS-ECDH-ECDSA-WITH-CAMELLIA-256-CBC-SHA384
|
||||
TLS-ECDH-ECDSA-WITH-CAMELLIA-256-GCM-SHA384
|
||||
TLS-ECDH-ECDSA-WITH-NULL-SHA
|
||||
TLS-ECDH-RSA-WITH-AES-128-CBC-SHA
|
||||
TLS-ECDH-RSA-WITH-AES-128-CBC-SHA256
|
||||
TLS-ECDH-RSA-WITH-AES-128-GCM-SHA256
|
||||
TLS-ECDH-RSA-WITH-AES-256-CBC-SHA
|
||||
TLS-ECDH-RSA-WITH-AES-256-CBC-SHA384
|
||||
TLS-ECDH-RSA-WITH-AES-256-GCM-SHA384
|
||||
TLS-ECDH-RSA-WITH-ARIA-128-CBC-SHA256
|
||||
TLS-ECDH-RSA-WITH-ARIA-128-GCM-SHA256
|
||||
TLS-ECDH-RSA-WITH-ARIA-256-CBC-SHA384
|
||||
TLS-ECDH-RSA-WITH-ARIA-256-GCM-SHA384
|
||||
TLS-ECDH-RSA-WITH-CAMELLIA-128-CBC-SHA256
|
||||
TLS-ECDH-RSA-WITH-CAMELLIA-128-GCM-SHA256
|
||||
TLS-ECDH-RSA-WITH-CAMELLIA-256-CBC-SHA384
|
||||
TLS-ECDH-RSA-WITH-CAMELLIA-256-GCM-SHA384
|
||||
TLS-ECDH-RSA-WITH-NULL-SHA
|
||||
TLS-RSA-PSK-WITH-AES-128-CBC-SHA
|
||||
TLS-RSA-PSK-WITH-AES-128-CBC-SHA256
|
||||
TLS-RSA-PSK-WITH-AES-128-GCM-SHA256
|
||||
TLS-RSA-PSK-WITH-AES-256-CBC-SHA
|
||||
TLS-RSA-PSK-WITH-AES-256-CBC-SHA384
|
||||
TLS-RSA-PSK-WITH-AES-256-GCM-SHA384
|
||||
TLS-RSA-PSK-WITH-ARIA-128-CBC-SHA256
|
||||
TLS-RSA-PSK-WITH-ARIA-128-GCM-SHA256
|
||||
TLS-RSA-PSK-WITH-ARIA-256-CBC-SHA384
|
||||
TLS-RSA-PSK-WITH-ARIA-256-GCM-SHA384
|
||||
TLS-RSA-PSK-WITH-CAMELLIA-128-CBC-SHA256
|
||||
TLS-RSA-PSK-WITH-CAMELLIA-128-GCM-SHA256
|
||||
TLS-RSA-PSK-WITH-CAMELLIA-256-CBC-SHA384
|
||||
TLS-RSA-PSK-WITH-CAMELLIA-256-GCM-SHA384
|
||||
TLS-RSA-PSK-WITH-CHACHA20-POLY1305-SHA256
|
||||
TLS-RSA-PSK-WITH-NULL-SHA
|
||||
TLS-RSA-PSK-WITH-NULL-SHA256
|
||||
TLS-RSA-PSK-WITH-NULL-SHA384
|
||||
TLS-RSA-WITH-AES-128-CBC-SHA
|
||||
TLS-RSA-WITH-AES-128-CBC-SHA256
|
||||
TLS-RSA-WITH-AES-128-CCM
|
||||
TLS-RSA-WITH-AES-128-CCM-8
|
||||
TLS-RSA-WITH-AES-128-GCM-SHA256
|
||||
TLS-RSA-WITH-AES-256-CBC-SHA
|
||||
TLS-RSA-WITH-AES-256-CBC-SHA256
|
||||
TLS-RSA-WITH-AES-256-CCM
|
||||
TLS-RSA-WITH-AES-256-CCM-8
|
||||
TLS-RSA-WITH-AES-256-GCM-SHA384
|
||||
TLS-RSA-WITH-ARIA-128-CBC-SHA256
|
||||
TLS-RSA-WITH-ARIA-128-GCM-SHA256
|
||||
TLS-RSA-WITH-ARIA-256-CBC-SHA384
|
||||
TLS-RSA-WITH-ARIA-256-GCM-SHA384
|
||||
TLS-RSA-WITH-CAMELLIA-128-CBC-SHA
|
||||
TLS-RSA-WITH-CAMELLIA-128-CBC-SHA256
|
||||
TLS-RSA-WITH-CAMELLIA-128-GCM-SHA256
|
||||
TLS-RSA-WITH-CAMELLIA-256-CBC-SHA
|
||||
TLS-RSA-WITH-CAMELLIA-256-CBC-SHA256
|
||||
TLS-RSA-WITH-CAMELLIA-256-GCM-SHA384
|
||||
TLS-RSA-WITH-NULL-MD5
|
||||
TLS-RSA-WITH-NULL-SHA
|
||||
TLS-RSA-WITH-NULL-SHA256
|
||||
```
|
||||
|
||||
As a consequence of the removal of support for DHE in (D)TLS 1.2, the following functions are no longer useful and have been removed:
|
||||
|
||||
```
|
||||
mbedtls_ssl_conf_dh_param_bin()
|
||||
mbedtls_ssl_conf_dh_param_ctx()
|
||||
mbedtls_ssl_conf_dhm_min_bitlen()
|
||||
```
|
||||
|
||||
### Removal of elliptic curves
|
||||
|
||||
Following their removal from the crypto library, elliptic curves of less than 250 bits (secp192r1, secp192k1, secp224r1, secp224k1) are no longer supported in certificates and in TLS.
|
||||
|
||||
### Removal of deprecated functions
|
||||
|
||||
The deprecated functions `mbedtls_ssl_conf_min_version()` and `mbedtls_ssl_conf_max_version()`, and the associated constants `MBEDTLS_SSL_MAJOR_VERSION_3`, `MBEDTLS_SSL_MINOR_VERSION_3` and `MBEDTLS_SSL_MINOR_VERSION_4` have been removed. Use `mbedtls_ssl_conf_min_tls_version()` and `mbedtls_ssl_conf_max_tls_version()` with `MBEDTLS_SSL_VERSION_TLS1_2` or `MBEDTLS_SSL_VERSION_TLS1_3` instead.
|
||||
|
||||
The deprecated function `mbedtls_ssl_conf_sig_hashes()` has been removed. Use `mbedtls_ssl_conf_sig_algs()` instead.
|
||||
@@ -1,89 +0,0 @@
|
||||
## Function prototype changes
|
||||
|
||||
A number of existing functions now take a different list of arguments, mostly to migrate them to the PSA API.
|
||||
|
||||
### Public functions no longer take a RNG callback
|
||||
|
||||
Functions that need randomness no longer take an RNG callback in the form of `f_rng, p_rng` arguments. Instead, they use the PSA Crypto random generator (accessible as `psa_generate_random()`). All software using the X.509 or SSL modules must call `psa_crypto_init()` before calling any of the functions listed here.
|
||||
|
||||
### RNG removal in X.509
|
||||
|
||||
The following function prototypes have been changed in `mbedtls/x509_crt.h`:
|
||||
|
||||
```c
|
||||
int mbedtls_x509write_crt_der(mbedtls_x509write_cert *ctx, unsigned char *buf, size_t size,
|
||||
int (*f_rng)(void *, unsigned char *, size_t),
|
||||
void *p_rng);
|
||||
|
||||
int mbedtls_x509write_crt_pem(mbedtls_x509write_cert *ctx, unsigned char *buf, size_t size,
|
||||
int (*f_rng)(void *, unsigned char *, size_t),
|
||||
void *p_rng);
|
||||
```
|
||||
|
||||
to
|
||||
|
||||
```c
|
||||
int mbedtls_x509write_crt_der(mbedtls_x509write_cert *ctx, unsigned char *buf, size_t size);
|
||||
|
||||
int mbedtls_x509write_crt_pem(mbedtls_x509write_cert *ctx, unsigned char *buf, size_t size);
|
||||
```
|
||||
|
||||
The following function prototypes have been changed in `mbedtls/x509_csr.h`:
|
||||
```c
|
||||
int mbedtls_x509write_csr_der(mbedtls_x509write_csr *ctx, unsigned char *buf, size_t size,
|
||||
int (*f_rng)(void *, unsigned char *, size_t),
|
||||
void *p_rng);
|
||||
|
||||
int mbedtls_x509write_csr_pem(mbedtls_x509write_csr *ctx, unsigned char *buf, size_t size,
|
||||
int (*f_rng)(void *, unsigned char *, size_t),
|
||||
void *p_rng);
|
||||
```
|
||||
|
||||
to
|
||||
|
||||
```c
|
||||
int mbedtls_x509write_csr_der(mbedtls_x509write_csr *ctx, unsigned char *buf, size_t size);
|
||||
|
||||
int mbedtls_x509write_csr_pem(mbedtls_x509write_csr *ctx, unsigned char *buf, size_t size);
|
||||
```
|
||||
|
||||
### RNG removal in SSL
|
||||
|
||||
The following function prototype has been changed in `mbedtls/ssl_cookie.h`:
|
||||
|
||||
```c
|
||||
int mbedtls_ssl_cookie_setup(mbedtls_ssl_cookie_ctx *ctx,
|
||||
int (*f_rng)(void *, unsigned char *, size_t),
|
||||
void *p_rng);
|
||||
```
|
||||
|
||||
to
|
||||
|
||||
```c
|
||||
int mbedtls_ssl_cookie_setup(mbedtls_ssl_cookie_ctx *ctx);
|
||||
```
|
||||
|
||||
### Removal of `mbedtls_ssl_conf_rng`
|
||||
|
||||
`mbedtls_ssl_conf_rng()` has been removed from the library. Its sole purpose was to configure the RNG used for TLS, but now the PSA Crypto random generator is used throughout the library.
|
||||
|
||||
### Changes to mbedtls_ssl_ticket_setup
|
||||
|
||||
In the arguments of the function `mbedtls_ssl_ticket_setup()`, the `mbedtls_cipher_type_t` argument specifying the AEAD mechanism for ticket protection has been replaced by an equivalent PSA description consisting of a key type, a size and an algorithm. Also, the function no longer takes RNG arguments.
|
||||
|
||||
The prototype in `mbedtls/ssl_ticket.h` has changed from
|
||||
|
||||
```c
|
||||
int mbedtls_ssl_ticket_setup(mbedtls_ssl_ticket_context *ctx,
|
||||
mbedtls_f_rng_t *f_rng, void *p_rng,
|
||||
mbedtls_cipher_type_t cipher,
|
||||
uint32_t lifetime);
|
||||
```
|
||||
|
||||
to
|
||||
|
||||
```c
|
||||
int mbedtls_ssl_ticket_setup(mbedtls_ssl_ticket_context *ctx,
|
||||
psa_algorithm_t alg, psa_key_type_t key_type, psa_key_bits_t key_bits,
|
||||
uint32_t lifetime);
|
||||
```
|
||||
@@ -1,7 +0,0 @@
|
||||
## OID module
|
||||
|
||||
The compilation option `MBEDTLS_OID_C` no longer exists. OID tables are included in the build automatically as needed for parsing and writing X.509 data.
|
||||
|
||||
Mbed TLS no longer offers interfaces to look up values by OID or OID by enum values (`mbedtls_oid_get_<thing>()` and `mbedtls_oid_get_oid_by_<thing>()`).
|
||||
|
||||
The header `<mbedtls/oid.h>` now only provides functions to convert between binary and dotted string OID representations. These functions are now part of `libmbedx509` rather than the crypto library. The function `mbedtls_oid_get_numeric_string()` is guarded by `MBEDTLS_X509_USE_C`, and `mbedtls_oid_from_numeric_string()` by `MBEDTLS_X509_CREATE_C`. The header also still defines macros for OID strings that are relevant to X.509.
|
||||
@@ -1,33 +0,0 @@
|
||||
## Private declarations
|
||||
|
||||
Since Mbed TLS 3.0, some things that are declared in a public header are not part of the stable application programming interface (API), but instead are considered private. Private elements may be removed or may have their semantics changed in a future minor release without notice.
|
||||
|
||||
### Understanding private declarations in public headers
|
||||
|
||||
In Mbed TLS 4.x, private elements in header files include:
|
||||
|
||||
* Anything appearing in a header file whose path contains `/private` (unless re-exported and documented in another non-private header).
|
||||
* Structure and union fields declared with `MBEDTLS_PRIVATE(field_name)` in the source code, and appearing as `private_field_name` in the rendered documentation. (This was already the case since Mbed TLS 3.0.)
|
||||
* Any preprocessor macro that is not documented with a Doxygen comment.
|
||||
In the source code, Doxygen comments start with `/**` or `/*!`. If a macro only has a comment above that starts with `/*`, the macro is considered private.
|
||||
In the rendered documentation, private macros appear with only an automatically rendered parameter list, value and location, but no custom text.
|
||||
* Any declaration that is guarded by the preprocessor macro `MBEDTLS_DECLARE_PRIVATE_IDENTIFIERS`.
|
||||
|
||||
### Usage of private declarations
|
||||
|
||||
Some private declarations are present in public headers for technical reasons, because they need to be visible to the compiler. Others are present for historical reasons and may be cleaned up in later versions of the library. We strongly recommend against relying on these declarations, since they may be removed or may have their semantics changed without notice.
|
||||
|
||||
Note that Mbed TLS 4.0 still relies on some private interfaces of TF-PSA-Crypto 1.0. We expect to remove this reliance gradually in future minor releases.
|
||||
|
||||
Sample programs have not been fully updated yet and some of them might still
|
||||
use APIs that are no longer public. You can recognize them by the fact that they
|
||||
define the macro `MBEDTLS_DECLARE_PRIVATE_IDENTIFIERS` (or
|
||||
`MBEDTLS_ALLOW_PRIVATE_ACCESS`) at the very top (before including headers). When
|
||||
you see one of these two macros in a sample program, be aware it has not been
|
||||
updated and parts of it do not demonstrate current practice.
|
||||
|
||||
We strongly recommend against defining `MBEDTLS_DECLARE_PRIVATE_IDENTIFIERS` or
|
||||
`MBEDTLS_ALLOW_PRIVATE_ACCESS` in your own application. If you do so, your code
|
||||
may not compile or work with future minor releases. If there's something you
|
||||
want to do that you feel can only be achieved by using one of these two macros,
|
||||
please reach out on github or the mailing list.
|
||||
@@ -1,23 +0,0 @@
|
||||
## PSA as the only cryptography API
|
||||
|
||||
The PSA API is now the only API for cryptographic primitives.
|
||||
|
||||
### Impact on application code
|
||||
|
||||
The X.509, PKCS7 and SSL modules always use PSA for cryptography, with a few exceptions documented in the [PSA limitations](../architecture/psa-migration/psa-limitations.md) document. (These limitations are mostly transparent unless you want to leverage PSA accelerator drivers.) This corresponds to the behavior of Mbed TLS 3.x when `MBEDTLS_USE_PSA_CRYPTO` is enabled. In effect, `MBEDTLS_USE_PSA_CRYPTO` is now always enabled.
|
||||
|
||||
`psa_crypto_init()` must be called before performing any cryptographic operation, including indirect requests such as parsing a key or certificate or starting a TLS handshake.
|
||||
|
||||
A few functions take different parameters to migrate them to the PSA API. See “[Function prototype changes](#function-prototype-changes)”.
|
||||
|
||||
### No random generator instantiation
|
||||
|
||||
Formerly, applications using TLS, asymmetric cryptography operations involving a private key, or other features needing random numbers, needed to provide a random generator, generally by instantiating an entropy context (`mbedtls_entropy_context`) and a DRBG context (`mbedtls_ctr_drbg_context` or `mbedtls_hmac_drbg_context`). This is no longer necessary, or possible. All features that require a random generator (RNG) now use the one provided by the PSA subsystem.
|
||||
|
||||
Instead, applications that use random generators or keys (even public keys) need to call `psa_crypto_init()` before any cryptographic operation or key management operation.
|
||||
|
||||
See also [function prototype changes](#function-prototype-changes), many of which are related to the move from RNG callbacks to a global RNG.
|
||||
|
||||
### Impact on the library configuration
|
||||
|
||||
Mbed TLS follows the configuration of TF-PSA-Crypto with respect to cryptographic mechanisms. They are now based on `PSA_WANT_xxx` macros instead of legacy configuration macros such as `MBEDTLS_RSA_C`, `MBEDTLS_PKCS1_V15`, etc. The configuration of X.509 and TLS is not directly affected by the configuration. However, applications and middleware that rely on these configuration symbols to know which cryptographic mechanisms to support will need to migrate to `PSA_WANT_xxx` macros. For more information, consult the PSA transition guide in TF-PSA-Crypto.
|
||||
Reference in New Issue
Block a user