Add cache configurability about python-mbedtls

[cartoush]

It might do the trick yes, i'll try that, thanks !

[Synss]

Hi! Thank you for your feedback. That seems reasonable but not entirely trivial as I will need to wrap an mbedtls_ssl_cache_context * as well. I will look into it.

[Note to self] mbedtls docs:

• mbedtls_ssl_conf_session_cache
• mbedtls_ssl_cache_set_timeout
• mbedtls_ssl_cache_set_max_entries

[cartoush]

Thanks a lot !

[Synss]

mbedtls_ssl_conf_session_cache() is tricky with its two callbacks. Would changing the defaults of the C library be an option for your tests?

https://github.com/ARMmbed/mbedtls/blob/v2.16.12/include/mbedtls/ssl_cache.h#L72-L78

#if !defined(MBEDTLS_SSL_CACHE_DEFAULT_TIMEOUT)
#define MBEDTLS_SSL_CACHE_DEFAULT_TIMEOUT       86400   /*!< 1 day  */
#endif

#if !defined(MBEDTLS_SSL_CACHE_DEFAULT_MAX_ENTRIES)
#define MBEDTLS_SSL_CACHE_DEFAULT_MAX_ENTRIES      50   /*!< Maximum entries in cache */
#endif

Please have a look here to recompile the C library and its bindings.