How do I configure mbed TLS-如何配置mbed TLS工程

朴灿烈づ我的快乐病毒、 2022-10-03 00:54 98阅读 0赞

mbed TLS should build out-of-the box on a large variety of platforms. However, you may need to adjust a few platform-specific settings or want to customize the set of features that will be built. All of this is done in a single configuration file.

## The configuration file ##

The default configuration file is located in *include/mbedtls/config.h*. It is [fully documented][] and divided into sections:

*  **System support** is where you select options depending on your platform: does your compiler support inline assembly, does your libc/network stack provide IPv6, etc.
 *  **mbed TLS feature support** is where you select which features will be enabled in the corresponding modules: which TLS version to support, which key exchanges, which specific elliptic curves, etc.
 *  **mbed TLS modules** is where you select the modules to be built. Here you can, for example, totally disable RSA or MD5 if you don't need them.
 *  **Module configuration options** is where you can set specific options for the each module, such as the maximum size of multi-precision integers, the size of the internal I/O buffers for SSL, etc. All of them have reasonable default values.

## The configuration script ##

The configuration file can of course be edited manually with the text editor of your choice. In some cases however it may be useful to set options in a more programmatic way; we provide a Perl script *scripts/config.pl* for doing so. Usage is as follows:

scripts/config.pl unset <name>
    scripts/config.pl set <name> [<value>]

When run this way, from mbed TLS's root directory, the config script automatically finds the *config.h*file. If you want to run it from another directory or on an other configuration file (see below), you'll need to use the *-f* option.

## Alternative configuration files ##

Sometimes it is desirable to keep the custom configuration file for your application outside the mbed TLS source tree. This can be easily achieved by defining the macro **MBEDTLS\_CONFIG\_FILE** to the desired filename (including the quote or angular brackets) at compile time. For example, using make:

CFLAGS="-Ipath/to/config -DMBEDTLS_CONFIG_FILE='<my_config.h>'" make

or, using Cmake (and clearing its cache first in case it's not the first run):

find . -iname '*cmake*' -not -name CMakeLists.txt -exec rm -rf {} +
    CFLAGS="-Ipath/to/config -DMBEDTLS_CONFIG_FILE='<my_config.h>'" cmake .
    make

We provide a file *check\_config.h* which checks consistency of the configuration file. It is highly recommended to *\#include* it at the end of your custom configuration file. When using the above setup, you may need to adapt the include directive depending on your compiler.

## Example configurations ##

We provide example configurations in the *configs* directory. These are often minimal configurations for a specific goal, such as supporting the NSA suite B TLS profile. They also often include settings to [reduce resource usage][].

### Did this help? ###

[fully documented]: https://tls.mbed.org/api/config_8h.html
[reduce resource usage]: https://tls.mbed.org/kb/how-to/reduce-mbedtls-memory-and-storage-footprint