+++ /dev/null
-=pod
-
-=head1 NAME
-
-EVP_PKEY_CTX_set_tls1_prf_md,
-EVP_PKEY_CTX_set1_tls1_prf_secret, EVP_PKEY_CTX_add1_tls1_prf_seed -
-TLS PRF key derivation algorithm
-
-=head1 SYNOPSIS
-
- #include <openssl/kdf.h>
-
- int EVP_PKEY_CTX_set_tls1_prf_md(EVP_PKEY_CTX *pctx, const EVP_MD *md);
- int EVP_PKEY_CTX_set1_tls1_prf_secret(EVP_PKEY_CTX *pctx,
- unsigned char *sec, int seclen);
- int EVP_PKEY_CTX_add1_tls1_prf_seed(EVP_PKEY_CTX *pctx, seed, seedlen)
- unsigned char *seed, int seedlen);
-
-=head1 DESCRIPTION
-
-The B<EVP_PKEY_TLS1_PRF> algorithm implements the PRF key derivation function for
-TLS. It has no associated private key and only implements key derivation
-using EVP_PKEY_derive().
-
-EVP_PKEY_set_tls1_prf_md() sets the message digest associated with the
-TLS PRF. EVP_md5_sha1() is treated as a special case which uses the PRF
-algorithm using both B<MD5> and B<SHA1> as used in TLS 1.0 and 1.1.
-
-EVP_PKEY_CTX_set_tls1_prf_secret() sets the secret value of the TLS PRF
-to B<seclen> bytes of the buffer B<sec>. Any existing secret value is replaced
-and any seed is reset.
-
-EVP_PKEY_CTX_add1_tls1_prf_seed() sets the seed to B<seedlen> bytes of B<seed>.
-If a seed is already set it is appended to the existing value.
-
-=head1 STRING CTRLS
-
-The TLS PRF also supports string based control operations using
-L<EVP_PKEY_CTX_ctrl_str(3)>.
-The B<type> parameter "md" uses the supplied B<value> as the name of the digest
-algorithm to use.
-The B<type> parameters "secret" and "seed" use the supplied B<value> parameter
-as a secret or seed value.
-The names "hexsecret" and "hexseed" are similar except they take a hex string
-which is converted to binary.
-
-=head1 NOTES
-
-All these functions are implemented as macros.
-
-A context for the TLS PRF can be obtained by calling:
-
- EVP_PKEY_CTX *pctx = EVP_PKEY_new_id(EVP_PKEY_TLS1_PRF, NULL);
-
-The digest, secret value and seed must be set before a key is derived or an
-error occurs.
-
-The total length of all seeds cannot exceed 1024 bytes in length: this should
-be more than enough for any normal use of the TLS PRF.
-
-The output length of the PRF is specified by the length parameter in the
-EVP_PKEY_derive() function. Since the output length is variable, setting
-the buffer to B<NULL> is not meaningful for the TLS PRF.
-
-Optimised versions of the TLS PRF can be implemented in an ENGINE.
-
-=head1 RETURN VALUES
-
-All these functions return 1 for success and 0 or a negative value for failure.
-In particular a return value of -2 indicates the operation is not supported by
-the public key algorithm.
-
-=head1 EXAMPLE
-
-This example derives 10 bytes using SHA-256 with the secret key "secret"
-and seed value "seed":
-
- EVP_PKEY_CTX *pctx;
- unsigned char out[10];
- size_t outlen = sizeof(out);
- pctx = EVP_PKEY_CTX_new_id(EVP_PKEY_TLS1_PRF, NULL);
- if (EVP_PKEY_derive_init(pctx) <= 0)
- /* Error */
- if (EVP_PKEY_CTX_set_tls1_prf_md(pctx, EVP_sha256()) <= 0)
- /* Error */
- if (EVP_PKEY_CTX_set1_tls1_prf_secret(pctx, "secret", 6) <= 0)
- /* Error */
- if (EVP_PKEY_CTX_add1_tls1_prf_seed(pctx, "seed", 4) <= 0)
- /* Error */
- if (EVP_PKEY_derive(pctx, out, &outlen) <= 0)
- /* Error */
-
-=head1 SEE ALSO
-
-L<EVP_PKEY_CTX_new(3)>,
-L<EVP_PKEY_CTX_ctrl_str(3)>,
-L<EVP_PKEY_derive(3)>
-
-=head1 COPYRIGHT
-
-Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
-
-Licensed under the OpenSSL license (the "License"). You may not use
-this file except in compliance with the License. You can obtain a copy
-in the file LICENSE in the source distribution or at
-L<https://www.openssl.org/source/license.html>.
-
-=cut
projects / openssl.git / blobdiff