is a gnutls_session_t type.
length of the label variable.
const char * label
label used in PRF computation, typically a short
length of the extra variable.
const char * context
optional extra data to seed the PRF with.
size of pre-allocated output buffer to hold the
char * out pre-allocated buffer to hold the generated data.
This function is similar to gnutls_prf_rfc5705(), but only works
in TLS 1.3 or later to export early keying material.
Note that the keying material is only available after the
ClientHello message is processed and before the application
traffic keys are established. Therefore this function shall be
called in a handshake hook function for
The label variable usually contains a string denoting the
purpose for the generated data.
The context variable can be used to add more data to the seed,
after the random variables. It can be used to make sure the
generated output is strongly connected to some additional data
(e.g., a string used in user authentication).
The output is placed in out , which must be pre-allocated.
Note that, to provide the RFC5705 context, the context variable
must be non-null.
This page is part of the GnuTLS (GnuTLS Transport Layer Security
Library) project. Information about the project can be found at
⟨http://www.gnutls.org/⟩. If you have a bug report for this
manual page, send it to firstname.lastname@example.org. This page was obtained
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gnutls 3.7.1 gnutls_prf_early(3)