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Diffstat (limited to 'doc/man3/DH_get0_pqg.pod')
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diff --git a/doc/man3/DH_get0_pqg.pod b/doc/man3/DH_get0_pqg.pod new file mode 100644 index 0000000000..79647bf890 --- /dev/null +++ b/doc/man3/DH_get0_pqg.pod @@ -0,0 +1,112 @@ +=pod + +=head1 NAME + +DH_get0_pqg, DH_set0_pqg, DH_get0_key, DH_set0_key, DH_clear_flags, +DH_test_flags, DH_set_flags, DH_get0_engine, DH_get_length, +DH_set_length - Routines for getting and setting data in a DH object + +=head1 SYNOPSIS + + #include <openssl/dh.h> + + void DH_get0_pqg(const DH *dh, + const BIGNUM **p, const BIGNUM **q, const BIGNUM **g); + int DH_set0_pqg(DH *dh, BIGNUM *p, BIGNUM *q, BIGNUM *g); + void DH_get0_key(const DH *dh, + const BIGNUM **pub_key, const BIGNUM **priv_key); + int DH_set0_key(DH *dh, BIGNUM *pub_key, BIGNUM *priv_key); + void DH_clear_flags(DH *dh, int flags); + int DH_test_flags(const DH *dh, int flags); + void DH_set_flags(DH *dh, int flags); + ENGINE *DH_get0_engine(DH *d); + long DH_get_length(const DH *dh); + int DH_set_length(DH *dh, long length); + +=head1 DESCRIPTION + +A DH object contains the parameters B<p>, B<q> and B<g>. Note that the B<q> +parameter is optional. It also contains a public key (B<pub_key>) and +(optionally) a private key (B<priv_key>). + +The B<p>, B<q> and B<g> parameters can be obtained by calling DH_get0_pqg(). +If the parameters have not yet been set then B<*p>, B<*q> and B<*g> will be set +to NULL. Otherwise they are set to pointers to their respective values. These +point directly to the internal representations of the values and therefore +should not be freed directly. + +The B<p>, B<q> and B<g> values can be set by calling DH_set0_pqg() and passing +the new values for B<p>, B<q> and B<g> as parameters to the function. Calling +this function transfers the memory management of the values to the DH object, +and therefore the values that have been passed in should not be freed directly +after this function has been called. The B<q> parameter may be NULL. + +To get the public and private key values use the DH_get0_key() function. A +pointer to the public key will be stored in B<*pub_key>, and a pointer to the +private key will be stored in B<*priv_key>. Either may be NULL if they have not +been set yet, although if the private key has been set then the public key must +be. The values point to the internal representation of the public key and +private key values. This memory should not be freed directly. + +The public and private key values can be set using DH_set0_key(). The public +key must be non-NULL the first time this function is called on a given DH +object. The private key may be NULL. On subsequent calls, either may be NULL, +which means the corresponding DH field is left untouched. As for DH_set0_pqg() +this function transfers the memory management of the key values to the DH +object, and therefore they should not be freed directly after this function has +been called. + +DH_set_flags() sets the flags in the B<flags> parameter on the DH object. +Multiple flags can be passed in one go (bitwise ORed together). Any flags that +are already set are left set. DH_test_flags() tests to see whether the flags +passed in the B<flags> parameter are currently set in the DH object. Multiple +flags can be tested in one go. All flags that are currently set are returned, or +zero if none of the flags are set. DH_clear_flags() clears the specified flags +within the DH object. + +DH_get0_engine() returns a handle to the ENGINE that has been set for this DH +object, or NULL if no such ENGINE has been set. + +The DH_get_length() and DH_set_length() functions get and set the optional +length parameter associated with this DH object. If the length is non-zero then +it is used, otherwise it is ignored. The B<length> parameter indicates the +length of the secret exponent (private key) in bits. + +=head1 NOTES + +Values retrieved with DH_get0_key() are owned by the DH object used +in the call and may therefore I<not> be passed to DH_set0_key(). If +needed, duplicate the received value using BN_dup() and pass the +duplicate. The same applies to DH_get0_pqg() and DH_set0_pqg(). + +=head1 RETURN VALUES + +DH_set0_pqg() and DH_set0_key() return 1 on success or 0 on failure. + +DH_test_flags() returns the current state of the flags in the DH object. + +DH_get0_engine() returns the ENGINE set for the DH object or NULL if no ENGINE +has been set. + +DH_get_length() returns the length of the secret exponent (private key) in bits, +or zero if no such length has been explicitly set. + +=head1 SEE ALSO + +L<dh(3)>, L<DH_new(3)>, L<DH_generate_parameters(3)>, L<DH_generate_key(3)>, +L<DH_set_method(3)>, L<DH_size(3)>, L<DH_meth_new(3)> + +=head1 HISTORY + +The functions described here were added in OpenSSL version 1.1.0. + +=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 |