1DH_GET0_PQG(3) OpenSSL DH_GET0_PQG(3)
2
6 DH_get0_pqg, DH_set0_pqg, DH_get0_key, DH_set0_key, DH_get0_p,
7 DH_get0_q, DH_get0_g, DH_get0_priv_key, DH_get0_pub_key,
8 DH_clear_flags, DH_test_flags, DH_set_flags, DH_get0_engine,
9 DH_get_length, DH_set_length - Routines for getting and setting data in
10 a DH object
11
13 #include <openssl/dh.h>
14 void DH_get0_pqg(const DH *dh,
16 const BIGNUM **p, const BIGNUM **q, const BIGNUM **g);
17 int DH_set0_pqg(DH *dh, BIGNUM *p, BIGNUM *q, BIGNUM *g);
18 void DH_get0_key(const DH *dh,
19 const BIGNUM **pub_key, const BIGNUM **priv_key);
20 int DH_set0_key(DH *dh, BIGNUM *pub_key, BIGNUM *priv_key);
21 const BIGNUM *DH_get0_p(const DH *dh);
22 const BIGNUM *DH_get0_q(const DH *dh);
23 const BIGNUM *DH_get0_g(const DH *dh);
24 const BIGNUM *DH_get0_priv_key(const DH *dh);
25 const BIGNUM *DH_get0_pub_key(const DH *dh);
26 void DH_clear_flags(DH *dh, int flags);
27 int DH_test_flags(const DH *dh, int flags);
28 void DH_set_flags(DH *dh, int flags);
29 ENGINE *DH_get0_engine(DH *d);
30 long DH_get_length(const DH *dh);
31 int DH_set_length(DH *dh, long length);
32
34 A DH object contains the parameters p, q and g. Note that the q
35 parameter is optional. It also contains a public key (pub_key) and
36 (optionally) a private key (priv_key).
37 The p, q and g parameters can be obtained by calling DH_get0_pqg(). If
39 the parameters have not yet been set then *p, *q and *g will be set to
40 NULL. Otherwise they are set to pointers to their respective values.
41 These point directly to the internal representations of the values and
42 therefore should not be freed directly. Any of the out parameters p,
43 q, and g can be NULL, in which case no value will be returned for that
44 parameter.
45 The p, q and g values can be set by calling DH_set0_pqg() and passing
47 the new values for p, q and g as parameters to the function. Calling
48 this function transfers the memory management of the values to the DH
49 object, and therefore the values that have been passed in should not be
50 freed directly after this function has been called. The q parameter may
51 be NULL.
52 To get the public and private key values use the DH_get0_key()
54 function. A pointer to the public key will be stored in *pub_key, and a
55 pointer to the private key will be stored in *priv_key. Either may be
56 NULL if they have not been set yet, although if the private key has
57 been set then the public key must be. The values point to the internal
58 representation of the public key and private key values. This memory
59 should not be freed directly. Any of the out parameters pub_key and
60 priv_key can be NULL, in which case no value will be returned for that
61 parameter.
62 The public and private key values can be set using DH_set0_key().
64 Either parameter may be NULL, which means the corresponding DH field is
65 left untouched. As with DH_set0_pqg() this function transfers the
66 memory management of the key values to the DH object, and therefore
67 they should not be freed directly after this function has been called.
68 Any of the values p, q, g, priv_key, and pub_key can also be retrieved
70 separately by the corresponding function DH_get0_p(), DH_get0_q(),
71 DH_get0_g(), DH_get0_priv_key(), and DH_get0_pub_key(), respectively.
72 DH_set_flags() sets the flags in the flags parameter on the DH object.
74 Multiple flags can be passed in one go (bitwise ORed together). Any
75 flags that are already set are left set. DH_test_flags() tests to see
76 whether the flags passed in the flags parameter are currently set in
77 the DH object. Multiple flags can be tested in one go. All flags that
78 are currently set are returned, or zero if none of the flags are set.
79 DH_clear_flags() clears the specified flags within the DH object.
80 DH_get0_engine() returns a handle to the ENGINE that has been set for
82 this DH object, or NULL if no such ENGINE has been set.
83 The DH_get_length() and DH_set_length() functions get and set the
85 optional length parameter associated with this DH object. If the length
86 is nonzero then it is used, otherwise it is ignored. The length
87 parameter indicates the length of the secret exponent (private key) in
88 bits.
89
91 Values retrieved with DH_get0_key() are owned by the DH object used in
92 the call and may therefore not be passed to DH_set0_key(). If needed,
93 duplicate the received value using BN_dup() and pass the duplicate.
94 The same applies to DH_get0_pqg() and DH_set0_pqg().
95
97 DH_set0_pqg() and DH_set0_key() return 1 on success or 0 on failure.
98 DH_get0_p(), DH_get0_q(), DH_get0_g(), DH_get0_priv_key(), and
100 DH_get0_pub_key() return the respective value, or NULL if it is unset.
101 DH_test_flags() returns the current state of the flags in the DH
103 object.
104 DH_get0_engine() returns the ENGINE set for the DH object or NULL if no
106 ENGINE has been set.
107 DH_get_length() returns the length of the secret exponent (private key)
109 in bits, or zero if no such length has been explicitly set.
110
112 DH_new(3), DH_new(3), DH_generate_parameters(3), DH_generate_key(3),
113 DH_set_method(3), DH_size(3), DH_meth_new(3)
114
116 The functions described here were added in OpenSSL 1.1.0.
117
119 Copyright 2016-2020 The OpenSSL Project Authors. All Rights Reserved.
120 Licensed under the OpenSSL license (the "License"). You may not use
122 this file except in compliance with the License. You can obtain a copy
123 in the file LICENSE in the source distribution or at
124 <https://www.openssl.org/source/license.html>.
1251.1.1k 2021-03-26 DH_GET0_PQG(3)