Section: gnutls (3)
gnutls_prf_rfc5705 - API function
int gnutls_prf_rfc5705(gnutls_session_t session, size_t label_size, const char * label, size_t context_size, const char * context, size_t outsize, char * out);
- gnutls_session_t session
is a gnutls_session_t type.
- size_t label_size
length of the label variable.
- const char * label
label used in PRF computation, typically a short string.
- size_t context_size
length of the extra variable.
- const char * context
optional extra data to seed the PRF with.
- size_t outsize
size of pre-allocated output buffer to hold the output.
- char * out
pre-allocated buffer to hold the generated data.
Exports keying material from TLS/DTLS session to an application, as
specified in RFC5705.
In the TLS versions prior to 1.3, it applies the TLS
Pseudo-Random-Function (PRF) on the master secret and the provided
data, seeded with the client and server random fields.
In TLS 1.3, it applies HKDF on the exporter master secret derived
from the master secret.
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.
on success, or an error code.
Report bugs to <email@example.com
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