xref: /openssl/doc/man3/RSA_get0_key.pod (revision fecb3aae) 
1=pod
2
3=head1 NAME
4
5RSA_set0_key, RSA_set0_factors, RSA_set0_crt_params, RSA_get0_key,
6RSA_get0_factors, RSA_get0_crt_params,
7RSA_get0_n, RSA_get0_e, RSA_get0_d, RSA_get0_p, RSA_get0_q,
8RSA_get0_dmp1, RSA_get0_dmq1, RSA_get0_iqmp, RSA_get0_pss_params,
9RSA_clear_flags,
10RSA_test_flags, RSA_set_flags, RSA_get0_engine, RSA_get_multi_prime_extra_count,
11RSA_get0_multi_prime_factors, RSA_get0_multi_prime_crt_params,
12RSA_set0_multi_prime_params, RSA_get_version
13- Routines for getting and setting data in an RSA object
14
15=head1 SYNOPSIS
16
17 #include <openssl/rsa.h>
18
19The following functions have been deprecated since OpenSSL 3.0, and can be
20hidden entirely by defining B<OPENSSL_API_COMPAT> with a suitable version value,
21see L<openssl_user_macros(7)>:
22
23 int RSA_set0_key(RSA *r, BIGNUM *n, BIGNUM *e, BIGNUM *d);
24 int RSA_set0_factors(RSA *r, BIGNUM *p, BIGNUM *q);
25 int RSA_set0_crt_params(RSA *r, BIGNUM *dmp1, BIGNUM *dmq1, BIGNUM *iqmp);
26 void RSA_get0_key(const RSA *r,
27                   const BIGNUM **n, const BIGNUM **e, const BIGNUM **d);
28 void RSA_get0_factors(const RSA *r, const BIGNUM **p, const BIGNUM **q);
29 void RSA_get0_crt_params(const RSA *r,
30                          const BIGNUM **dmp1, const BIGNUM **dmq1,
31                          const BIGNUM **iqmp);
32 const BIGNUM *RSA_get0_n(const RSA *d);
33 const BIGNUM *RSA_get0_e(const RSA *d);
34 const BIGNUM *RSA_get0_d(const RSA *d);
35 const BIGNUM *RSA_get0_p(const RSA *d);
36 const BIGNUM *RSA_get0_q(const RSA *d);
37 const BIGNUM *RSA_get0_dmp1(const RSA *r);
38 const BIGNUM *RSA_get0_dmq1(const RSA *r);
39 const BIGNUM *RSA_get0_iqmp(const RSA *r);
40 const RSA_PSS_PARAMS *RSA_get0_pss_params(const RSA *r);
41 void RSA_clear_flags(RSA *r, int flags);
42 int RSA_test_flags(const RSA *r, int flags);
43 void RSA_set_flags(RSA *r, int flags);
44 ENGINE *RSA_get0_engine(RSA *r);
45 int RSA_get_multi_prime_extra_count(const RSA *r);
46 int RSA_get0_multi_prime_factors(const RSA *r, const BIGNUM *primes[]);
47 int RSA_get0_multi_prime_crt_params(const RSA *r, const BIGNUM *exps[],
48                                     const BIGNUM *coeffs[]);
49 int RSA_set0_multi_prime_params(RSA *r, BIGNUM *primes[], BIGNUM *exps[],
50                                BIGNUM *coeffs[], int pnum);
51 int RSA_get_version(RSA *r);
52
53=head1 DESCRIPTION
54
55All of the functions described on this page are deprecated.
56Applications should instead use L<EVP_PKEY_get_bn_param(3)> for any methods that
57return a B<BIGNUM>. Refer to L<EVP_PKEY-DH(7)> for more information.
58
59An RSA object contains the components for the public and private key,
60B<n>, B<e>, B<d>, B<p>, B<q>, B<dmp1>, B<dmq1> and B<iqmp>.  B<n> is
61the modulus common to both public and private key, B<e> is the public
62exponent and B<d> is the private exponent.  B<p>, B<q>, B<dmp1>,
63B<dmq1> and B<iqmp> are the factors for the second representation of a
64private key (see PKCS#1 section 3 Key Types), where B<p> and B<q> are
65the first and second factor of B<n> and B<dmp1>, B<dmq1> and B<iqmp>
66are the exponents and coefficient for CRT calculations.
67
68For multi-prime RSA (defined in RFC 8017), there are also one or more
69'triplet' in an RSA object. A triplet contains three members, B<r>, B<d>
70and B<t>. B<r> is the additional prime besides B<p> and B<q>. B<d> and
71B<t> are the exponent and coefficient for CRT calculations.
72
73The B<n>, B<e> and B<d> parameters can be obtained by calling
74RSA_get0_key().  If they have not been set yet, then B<*n>, B<*e> and
75B<*d> will be set to NULL.  Otherwise, they are set to pointers to
76their respective values. These point directly to the internal
77representations of the values and therefore should not be freed
78by the caller.
79
80The B<n>, B<e> and B<d> parameter values can be set by calling
81RSA_set0_key() and passing the new values for B<n>, B<e> and B<d> as
82parameters to the function.  The values B<n> and B<e> must be non-NULL
83the first time this function is called on a given RSA object. The
84value B<d> may be NULL. On subsequent calls any of these values may be
85NULL which means the corresponding RSA field is left untouched.
86Calling this function transfers the memory management of the values to
87the RSA object, and therefore the values that have been passed in
88should not be freed by the caller after this function has been called.
89
90In a similar fashion, the B<p> and B<q> parameters can be obtained and
91set with RSA_get0_factors() and RSA_set0_factors(), and the B<dmp1>,
92B<dmq1> and B<iqmp> parameters can be obtained and set with
93RSA_get0_crt_params() and RSA_set0_crt_params().
94
95For RSA_get0_key(), RSA_get0_factors(), and RSA_get0_crt_params(),
96NULL value BIGNUM ** output parameters are permitted. The functions
97ignore NULL parameters but return values for other, non-NULL, parameters.
98
99For multi-prime RSA, RSA_get0_multi_prime_factors() and RSA_get0_multi_prime_params()
100can be used to obtain other primes and related CRT parameters. The
101return values are stored in an array of B<BIGNUM *>. RSA_set0_multi_prime_params()
102sets a collect of multi-prime 'triplet' members (prime, exponent and coefficient)
103into an RSA object.
104
105Any of the values B<n>, B<e>, B<d>, B<p>, B<q>, B<dmp1>, B<dmq1>, and B<iqmp> can also be
106retrieved separately by the corresponding function
107RSA_get0_n(), RSA_get0_e(), RSA_get0_d(), RSA_get0_p(), RSA_get0_q(),
108RSA_get0_dmp1(), RSA_get0_dmq1(), and RSA_get0_iqmp(), respectively.
109
110RSA_get0_pss_params() is used to retrieve the RSA-PSS parameters.
111
112RSA_set_flags() sets the flags in the B<flags> parameter on the RSA
113object. Multiple flags can be passed in one go (bitwise ORed together).
114Any flags that are already set are left set. RSA_test_flags() tests to
115see whether the flags passed in the B<flags> parameter are currently
116set in the RSA object. Multiple flags can be tested in one go. All
117flags that are currently set are returned, or zero if none of the
118flags are set. RSA_clear_flags() clears the specified flags within the
119RSA object.
120
121RSA_get0_engine() returns a handle to the ENGINE that has been set for
122this RSA object, or NULL if no such ENGINE has been set.
123
124RSA_get_version() returns the version of an RSA object B<r>.
125
126=head1 NOTES
127
128Values retrieved with RSA_get0_key() are owned by the RSA object used
129in the call and may therefore I<not> be passed to RSA_set0_key().  If
130needed, duplicate the received value using BN_dup() and pass the
131duplicate.  The same applies to RSA_get0_factors() and RSA_set0_factors()
132as well as RSA_get0_crt_params() and RSA_set0_crt_params().
133
134The caller should obtain the size by calling RSA_get_multi_prime_extra_count()
135in advance and allocate sufficient buffer to store the return values before
136calling RSA_get0_multi_prime_factors() and RSA_get0_multi_prime_params().
137
138RSA_set0_multi_prime_params() always clears the original multi-prime
139triplets in RSA object B<r> and assign the new set of triplets into it.
140
141=head1 RETURN VALUES
142
143RSA_set0_key(), RSA_set0_factors(), RSA_set0_crt_params() and
144RSA_set0_multi_prime_params() return 1 on success or 0 on failure.
145
146RSA_get0_n(), RSA_get0_e(), RSA_get0_d(), RSA_get0_p(), RSA_get0_q(),
147RSA_get0_dmp1(), RSA_get0_dmq1(), and RSA_get0_iqmp()
148return the respective value.
149
150RSA_get0_pss_params() returns a B<RSA_PSS_PARAMS> pointer, or NULL if
151there is none.
152
153RSA_get0_multi_prime_factors() and RSA_get0_multi_prime_crt_params() return
1541 on success or 0 on failure.
155
156RSA_get_multi_prime_extra_count() returns two less than the number of primes
157in use, which is 0 for traditional RSA and the number of extra primes for
158multi-prime RSA.
159
160RSA_get_version() returns B<RSA_ASN1_VERSION_MULTI> for multi-prime RSA and
161B<RSA_ASN1_VERSION_DEFAULT> for normal two-prime RSA, as defined in RFC 8017.
162
163RSA_test_flags() returns the current state of the flags in the RSA object.
164
165RSA_get0_engine() returns the ENGINE set for the RSA object or NULL if no
166ENGINE has been set.
167
168=head1 SEE ALSO
169
170L<RSA_new(3)>, L<RSA_size(3)>
171
172=head1 HISTORY
173
174The RSA_get0_pss_params() function was added in OpenSSL 1.1.1e.
175
176The
177RSA_get_multi_prime_extra_count(), RSA_get0_multi_prime_factors(),
178RSA_get0_multi_prime_crt_params(), RSA_set0_multi_prime_params(),
179and RSA_get_version() functions were added in OpenSSL 1.1.1.
180
181Other functions described here were added in OpenSSL 1.1.0.
182
183All of these functions were deprecated in OpenSSL 3.0.
184
185=head1 COPYRIGHT
186
187Copyright 2016-2022 The OpenSSL Project Authors. All Rights Reserved.
188
189Licensed under the Apache License 2.0 (the "License").  You may not use
190this file except in compliance with the License.  You can obtain a copy
191in the file LICENSE in the source distribution or at
192L<https://www.openssl.org/source/license.html>.
193
194=cut
195