5 EVP_PKEY_CTX_get_params,
6 EVP_PKEY_CTX_gettable_params,
7 EVP_PKEY_CTX_set_params,
8 EVP_PKEY_CTX_settable_params,
10 EVP_PKEY_CTX_ctrl_str,
11 EVP_PKEY_CTX_ctrl_uint64,
13 EVP_PKEY_CTX_set_signature_md,
14 EVP_PKEY_CTX_get_signature_md,
15 EVP_PKEY_CTX_set_mac_key,
16 EVP_PKEY_CTX_set_rsa_padding,
17 EVP_PKEY_CTX_get_rsa_padding,
18 EVP_PKEY_CTX_set_rsa_pss_saltlen,
19 EVP_PKEY_CTX_get_rsa_pss_saltlen,
20 EVP_PKEY_CTX_set_rsa_keygen_bits,
21 EVP_PKEY_CTX_set_rsa_keygen_pubexp,
22 EVP_PKEY_CTX_set_rsa_keygen_primes,
23 EVP_PKEY_CTX_set_rsa_mgf1_md,
24 EVP_PKEY_CTX_get_rsa_mgf1_md,
25 EVP_PKEY_CTX_set_rsa_oaep_md,
26 EVP_PKEY_CTX_get_rsa_oaep_md,
27 EVP_PKEY_CTX_set0_rsa_oaep_label,
28 EVP_PKEY_CTX_get0_rsa_oaep_label,
29 EVP_PKEY_CTX_set_dsa_paramgen_bits,
30 EVP_PKEY_CTX_set_dsa_paramgen_q_bits,
31 EVP_PKEY_CTX_set_dsa_paramgen_md,
32 EVP_PKEY_CTX_set_dh_paramgen_prime_len,
33 EVP_PKEY_CTX_set_dh_paramgen_subprime_len,
34 EVP_PKEY_CTX_set_dh_paramgen_generator,
35 EVP_PKEY_CTX_set_dh_paramgen_type,
36 EVP_PKEY_CTX_set_dh_rfc5114,
37 EVP_PKEY_CTX_set_dhx_rfc5114,
38 EVP_PKEY_CTX_set_dh_pad,
39 EVP_PKEY_CTX_set_dh_nid,
40 EVP_PKEY_CTX_set_dh_kdf_type,
41 EVP_PKEY_CTX_get_dh_kdf_type,
42 EVP_PKEY_CTX_set0_dh_kdf_oid,
43 EVP_PKEY_CTX_get0_dh_kdf_oid,
44 EVP_PKEY_CTX_set_dh_kdf_md,
45 EVP_PKEY_CTX_get_dh_kdf_md,
46 EVP_PKEY_CTX_set_dh_kdf_outlen,
47 EVP_PKEY_CTX_get_dh_kdf_outlen,
48 EVP_PKEY_CTX_set0_dh_kdf_ukm,
49 EVP_PKEY_CTX_get0_dh_kdf_ukm,
50 EVP_PKEY_CTX_set_ec_paramgen_curve_nid,
51 EVP_PKEY_CTX_set_ec_param_enc,
52 EVP_PKEY_CTX_set_ecdh_cofactor_mode,
53 EVP_PKEY_CTX_get_ecdh_cofactor_mode,
54 EVP_PKEY_CTX_set_ecdh_kdf_type,
55 EVP_PKEY_CTX_get_ecdh_kdf_type,
56 EVP_PKEY_CTX_set_ecdh_kdf_md,
57 EVP_PKEY_CTX_get_ecdh_kdf_md,
58 EVP_PKEY_CTX_set_ecdh_kdf_outlen,
59 EVP_PKEY_CTX_get_ecdh_kdf_outlen,
60 EVP_PKEY_CTX_set0_ecdh_kdf_ukm,
61 EVP_PKEY_CTX_get0_ecdh_kdf_ukm,
62 EVP_PKEY_CTX_set1_id, EVP_PKEY_CTX_get1_id, EVP_PKEY_CTX_get1_id_len
63 - algorithm specific control operations
67 #include <openssl/evp.h>
69 int EVP_PKEY_CTX_get_params(EVP_PKEY_CTX *ctx, OSSL_PARAM *params);
70 const OSSL_PARAM *EVP_PKEY_CTX_gettable_params(EVP_PKEY_CTX *ctx);
71 int EVP_PKEY_CTX_set_params(EVP_PKEY_CTX *ctx, OSSL_PARAM *params);
72 const OSSL_PARAM *EVP_PKEY_CTX_settable_params(EVP_PKEY_CTX *ctx);
74 int EVP_PKEY_CTX_ctrl(EVP_PKEY_CTX *ctx, int keytype, int optype,
75 int cmd, int p1, void *p2);
76 int EVP_PKEY_CTX_ctrl_uint64(EVP_PKEY_CTX *ctx, int keytype, int optype,
77 int cmd, uint64_t value);
78 int EVP_PKEY_CTX_ctrl_str(EVP_PKEY_CTX *ctx, const char *type,
81 int EVP_PKEY_CTX_md(EVP_PKEY_CTX *ctx, int optype, int cmd, const char *md);
83 int EVP_PKEY_CTX_set_signature_md(EVP_PKEY_CTX *ctx, const EVP_MD *md);
84 int EVP_PKEY_CTX_get_signature_md(EVP_PKEY_CTX *ctx, const EVP_MD **pmd);
86 int EVP_PKEY_CTX_set_mac_key(EVP_PKEY_CTX *ctx, const unsigned char *key,
89 #include <openssl/rsa.h>
91 int EVP_PKEY_CTX_set_rsa_padding(EVP_PKEY_CTX *ctx, int pad);
92 int EVP_PKEY_CTX_get_rsa_padding(EVP_PKEY_CTX *ctx, int *pad);
93 int EVP_PKEY_CTX_set_rsa_pss_saltlen(EVP_PKEY_CTX *ctx, int len);
94 int EVP_PKEY_CTX_get_rsa_pss_saltlen(EVP_PKEY_CTX *ctx, int *len);
95 int EVP_PKEY_CTX_set_rsa_keygen_bits(EVP_PKEY_CTX *ctx, int mbits);
96 int EVP_PKEY_CTX_set_rsa_keygen_pubexp(EVP_PKEY_CTX *ctx, BIGNUM *pubexp);
97 int EVP_PKEY_CTX_set_rsa_keygen_primes(EVP_PKEY_CTX *ctx, int primes);
98 int EVP_PKEY_CTX_set_rsa_mgf1_md(EVP_PKEY_CTX *ctx, const EVP_MD *md);
99 int EVP_PKEY_CTX_get_rsa_mgf1_md(EVP_PKEY_CTX *ctx, const EVP_MD **md);
100 int EVP_PKEY_CTX_set_rsa_oaep_md(EVP_PKEY_CTX *ctx, const EVP_MD *md);
101 int EVP_PKEY_CTX_get_rsa_oaep_md(EVP_PKEY_CTX *ctx, const EVP_MD **md);
102 int EVP_PKEY_CTX_set0_rsa_oaep_label(EVP_PKEY_CTX *ctx, unsigned char *label, int len);
103 int EVP_PKEY_CTX_get0_rsa_oaep_label(EVP_PKEY_CTX *ctx, unsigned char **label);
105 #include <openssl/dsa.h>
107 int EVP_PKEY_CTX_set_dsa_paramgen_bits(EVP_PKEY_CTX *ctx, int nbits);
108 int EVP_PKEY_CTX_set_dsa_paramgen_q_bits(EVP_PKEY_CTX *ctx, int qbits);
109 int EVP_PKEY_CTX_set_dsa_paramgen_md(EVP_PKEY_CTX *ctx, const EVP_MD *md);
111 #include <openssl/dh.h>
113 int EVP_PKEY_CTX_set_dh_paramgen_prime_len(EVP_PKEY_CTX *ctx, int len);
114 int EVP_PKEY_CTX_set_dh_paramgen_subprime_len(EVP_PKEY_CTX *ctx, int len);
115 int EVP_PKEY_CTX_set_dh_paramgen_generator(EVP_PKEY_CTX *ctx, int gen);
116 int EVP_PKEY_CTX_set_dh_paramgen_type(EVP_PKEY_CTX *ctx, int type);
117 int EVP_PKEY_CTX_set_dh_pad(EVP_PKEY_CTX *ctx, int pad);
118 int EVP_PKEY_CTX_set_dh_nid(EVP_PKEY_CTX *ctx, int nid);
119 int EVP_PKEY_CTX_set_dh_rfc5114(EVP_PKEY_CTX *ctx, int rfc5114);
120 int EVP_PKEY_CTX_set_dhx_rfc5114(EVP_PKEY_CTX *ctx, int rfc5114);
121 int EVP_PKEY_CTX_set_dh_kdf_type(EVP_PKEY_CTX *ctx, int kdf);
122 int EVP_PKEY_CTX_get_dh_kdf_type(EVP_PKEY_CTX *ctx);
123 int EVP_PKEY_CTX_set0_dh_kdf_oid(EVP_PKEY_CTX *ctx, ASN1_OBJECT *oid);
124 int EVP_PKEY_CTX_get0_dh_kdf_oid(EVP_PKEY_CTX *ctx, ASN1_OBJECT **oid);
125 int EVP_PKEY_CTX_set_dh_kdf_md(EVP_PKEY_CTX *ctx, const EVP_MD *md);
126 int EVP_PKEY_CTX_get_dh_kdf_md(EVP_PKEY_CTX *ctx, const EVP_MD **md);
127 int EVP_PKEY_CTX_set_dh_kdf_outlen(EVP_PKEY_CTX *ctx, int len);
128 int EVP_PKEY_CTX_get_dh_kdf_outlen(EVP_PKEY_CTX *ctx, int *len);
129 int EVP_PKEY_CTX_set0_dh_kdf_ukm(EVP_PKEY_CTX *ctx, unsigned char *ukm, int len);
130 int EVP_PKEY_CTX_get0_dh_kdf_ukm(EVP_PKEY_CTX *ctx, unsigned char **ukm);
132 #include <openssl/ec.h>
134 int EVP_PKEY_CTX_set_ec_paramgen_curve_nid(EVP_PKEY_CTX *ctx, int nid);
135 int EVP_PKEY_CTX_set_ec_param_enc(EVP_PKEY_CTX *ctx, int param_enc);
136 int EVP_PKEY_CTX_set_ecdh_cofactor_mode(EVP_PKEY_CTX *ctx, int cofactor_mode);
137 int EVP_PKEY_CTX_get_ecdh_cofactor_mode(EVP_PKEY_CTX *ctx);
138 int EVP_PKEY_CTX_set_ecdh_kdf_type(EVP_PKEY_CTX *ctx, int kdf);
139 int EVP_PKEY_CTX_get_ecdh_kdf_type(EVP_PKEY_CTX *ctx);
140 int EVP_PKEY_CTX_set_ecdh_kdf_md(EVP_PKEY_CTX *ctx, const EVP_MD *md);
141 int EVP_PKEY_CTX_get_ecdh_kdf_md(EVP_PKEY_CTX *ctx, const EVP_MD **md);
142 int EVP_PKEY_CTX_set_ecdh_kdf_outlen(EVP_PKEY_CTX *ctx, int len);
143 int EVP_PKEY_CTX_get_ecdh_kdf_outlen(EVP_PKEY_CTX *ctx, int *len);
144 int EVP_PKEY_CTX_set0_ecdh_kdf_ukm(EVP_PKEY_CTX *ctx, unsigned char *ukm, int len);
145 int EVP_PKEY_CTX_get0_ecdh_kdf_ukm(EVP_PKEY_CTX *ctx, unsigned char **ukm);
147 int EVP_PKEY_CTX_set1_id(EVP_PKEY_CTX *ctx, void *id, size_t id_len);
148 int EVP_PKEY_CTX_get1_id(EVP_PKEY_CTX *ctx, void *id);
149 int EVP_PKEY_CTX_get1_id_len(EVP_PKEY_CTX *ctx, size_t *id_len);
153 The EVP_PKEY_CTX_get_params() and EVP_PKEY_CTX_set_params() functions get and
154 send arbitrary parameters from and to the algorithm implementation respectively.
155 Not all parameters may be supported by all providers.
156 See L<OSSL_PROVIDER(3)> for more information on providers.
157 See L<OSSL_PARAM(3)> for more information on parameters.
158 These functions must only be called after the EVP_PKEY_CTX has been initialised
159 for use in an operation (for example by L<EVP_PKEY_sign_init_ex(3)>,
160 L<EVP_PKEY_derive_init_ex(3)> or other similar functions).
162 The parameters currently supported by the default provider are:
166 =item "pad" (B<OSSL_EXCHANGE_PARAM_PAD>) <uint>
168 Sets the DH padding mode.
169 If B<OSSL_EXCHANGE_PARAM_PAD> is 1 then the shared secret is padded with zeroes
170 up to the size of the DH prime B<p>.
171 If B<OSSL_EXCHANGE_PARAM_PAD> is zero (the default) then no padding is
174 =item "digest" (B<OSSL_SIGNATURE_PARAM_DIGEST>) <utf8 string>
176 Gets and sets the name of the digest algorithm used for the input to the
179 =item "digest-size" (B<OSSL_SIGNATURE_PARAM_DIGEST_SIZE>) <size_t>
181 Gets and sets the output size of the digest algorithm used for the input to the
183 The internal algorithm that supports this parameter is DSA.
187 EVP_PKEY_CTX_gettable_params() and EVP_PKEY_CTX_settable_params() gets a
188 constant B<OSSL_PARAM> array that decribes the gettable and
189 settable parameters for the current algorithm implementation, i.e. parameters
190 that can be used with EVP_PKEY_CTX_get_params() and EVP_PKEY_CTX_set_params()
192 See L<OSSL_PARAM(3)> for the use of B<OSSL_PARAM> as parameter descriptor.
193 These functions must only be called after the EVP_PKEY_CTX has been initialised
194 for use in an operation (for example by L<EVP_PKEY_sign_init_ex(3)>,
195 L<EVP_PKEY_derive_init_ex(3)> or other similar functions).
197 The function EVP_PKEY_CTX_ctrl() sends a control operation to the context
198 B<ctx>. The key type used must match B<keytype> if it is not -1. The parameter
199 B<optype> is a mask indicating which operations the control can be applied to.
200 The control command is indicated in B<cmd> and any additional arguments in
203 For B<cmd> = B<EVP_PKEY_CTRL_SET_MAC_KEY>, B<p1> is the length of the MAC key,
204 and B<p2> is MAC key. This is used by Poly1305, SipHash, HMAC and CMAC.
206 Applications will not normally call EVP_PKEY_CTX_ctrl() directly but will
207 instead call one of the algorithm specific macros below.
209 The function EVP_PKEY_CTX_ctrl_uint64() is a wrapper that directly passes a
210 uint64 value as B<p2> to EVP_PKEY_CTX_ctrl().
212 The function EVP_PKEY_CTX_ctrl_str() allows an application to send an algorithm
213 specific control operation to a context B<ctx> in string form. This is
214 intended to be used for options specified on the command line or in text
215 files. The commands supported are documented in the openssl utility
216 command line pages for the option B<-pkeyopt> which is supported by the
217 B<pkeyutl>, B<genpkey> and B<req> commands.
219 The function EVP_PKEY_CTX_md() sends a message digest control operation
220 to the context B<ctx>. The message digest is specified by its name B<md>.
222 The EVP_PKEY_CTX_set_signature_md() function sets the message digest type used
223 in a signature. It can be used in the RSA, DSA and ECDSA algorithms.
225 The EVP_PKEY_CTX_get_signature_md() function gets the message digest type used
226 in a signature. It can be used in the RSA, DSA and ECDSA algorithms.
228 All the remaining "functions" are implemented as macros.
230 Key generation typically involves setting up parameters to be used and
231 generating the private and public key data. Some algorithm implementations
232 allow private key data to be set explicitly using the EVP_PKEY_CTX_set_mac_key()
233 macro. In this case key generation is simply the process of setting up the
234 parameters for the key and then setting the raw key data to the value explicitly
235 provided by that macro. Normally applications would call
236 L<EVP_PKEY_new_raw_private_key(3)> or similar functions instead of this macro.
238 The EVP_PKEY_CTX_set_mac_key() macro can be used with any of the algorithms
239 supported by the L<EVP_PKEY_new_raw_private_key(3)> function.
241 =head2 RSA parameters
243 The EVP_PKEY_CTX_set_rsa_padding() macro sets the RSA padding mode for B<ctx>.
244 The B<pad> parameter can take the value B<RSA_PKCS1_PADDING> for PKCS#1
245 padding, B<RSA_SSLV23_PADDING> for SSLv23 padding, B<RSA_NO_PADDING> for
246 no padding, B<RSA_PKCS1_OAEP_PADDING> for OAEP padding (encrypt and
247 decrypt only), B<RSA_X931_PADDING> for X9.31 padding (signature operations
248 only) and B<RSA_PKCS1_PSS_PADDING> (sign and verify only).
250 Two RSA padding modes behave differently if EVP_PKEY_CTX_set_signature_md()
251 is used. If this macro is called for PKCS#1 padding the plaintext buffer is
252 an actual digest value and is encapsulated in a DigestInfo structure according
253 to PKCS#1 when signing and this structure is expected (and stripped off) when
254 verifying. If this control is not used with RSA and PKCS#1 padding then the
255 supplied data is used directly and not encapsulated. In the case of X9.31
256 padding for RSA the algorithm identifier byte is added or checked and removed
257 if this control is called. If it is not called then the first byte of the plaintext
258 buffer is expected to be the algorithm identifier byte.
260 The EVP_PKEY_CTX_get_rsa_padding() macro gets the RSA padding mode for B<ctx>.
262 The EVP_PKEY_CTX_set_rsa_pss_saltlen() macro sets the RSA PSS salt length to
263 B<len>. As its name implies it is only supported for PSS padding. Three special
264 values are supported: B<RSA_PSS_SALTLEN_DIGEST> sets the salt length to the
265 digest length, B<RSA_PSS_SALTLEN_MAX> sets the salt length to the maximum
266 permissible value. When verifying B<RSA_PSS_SALTLEN_AUTO> causes the salt length
267 to be automatically determined based on the B<PSS> block structure. If this
268 macro is not called maximum salt length is used when signing and auto detection
269 when verifying is used by default.
271 The EVP_PKEY_CTX_get_rsa_pss_saltlen() macro gets the RSA PSS salt length
272 for B<ctx>. The padding mode must have been set to B<RSA_PKCS1_PSS_PADDING>.
274 The EVP_PKEY_CTX_set_rsa_keygen_bits() macro sets the RSA key length for
275 RSA key generation to B<bits>. If not specified 1024 bits is used.
277 The EVP_PKEY_CTX_set_rsa_keygen_pubexp() macro sets the public exponent value
278 for RSA key generation to B<pubexp>. Currently it should be an odd integer. The
279 B<pubexp> pointer is used internally by this function so it should not be
280 modified or freed after the call. If not specified 65537 is used.
282 The EVP_PKEY_CTX_set_rsa_keygen_primes() macro sets the number of primes for
283 RSA key generation to B<primes>. If not specified 2 is used.
285 The EVP_PKEY_CTX_set_rsa_mgf1_md() macro sets the MGF1 digest for RSA padding
286 schemes to B<md>. If not explicitly set the signing digest is used. The
287 padding mode must have been set to B<RSA_PKCS1_OAEP_PADDING>
288 or B<RSA_PKCS1_PSS_PADDING>.
290 The EVP_PKEY_CTX_get_rsa_mgf1_md() macro gets the MGF1 digest for B<ctx>.
291 If not explicitly set the signing digest is used. The padding mode must have
292 been set to B<RSA_PKCS1_OAEP_PADDING> or B<RSA_PKCS1_PSS_PADDING>.
294 The EVP_PKEY_CTX_set_rsa_oaep_md() macro sets the message digest type used
295 in RSA OAEP to B<md>. The padding mode must have been set to
296 B<RSA_PKCS1_OAEP_PADDING>.
298 The EVP_PKEY_CTX_get_rsa_oaep_md() macro gets the message digest type used
299 in RSA OAEP to B<md>. The padding mode must have been set to
300 B<RSA_PKCS1_OAEP_PADDING>.
302 The EVP_PKEY_CTX_set0_rsa_oaep_label() macro sets the RSA OAEP label to
303 B<label> and its length to B<len>. If B<label> is NULL or B<len> is 0,
304 the label is cleared. The library takes ownership of the label so the
305 caller should not free the original memory pointed to by B<label>.
306 The padding mode must have been set to B<RSA_PKCS1_OAEP_PADDING>.
308 The EVP_PKEY_CTX_get0_rsa_oaep_label() macro gets the RSA OAEP label to
309 B<label>. The return value is the label length. The padding mode
310 must have been set to B<RSA_PKCS1_OAEP_PADDING>. The resulting pointer is owned
311 by the library and should not be freed by the caller.
313 =head2 DSA parameters
315 The EVP_PKEY_CTX_set_dsa_paramgen_bits() macro sets the number of bits used
316 for DSA parameter generation to B<nbits>. If not specified, 1024 is used.
318 The EVP_PKEY_CTX_set_dsa_paramgen_q_bits() macro sets the number of bits in the
319 subprime parameter B<q> for DSA parameter generation to B<qbits>. If not
320 specified, 160 is used. If a digest function is specified below, this parameter
321 is ignored and instead, the number of bits in B<q> matches the size of the
324 The EVP_PKEY_CTX_set_dsa_paramgen_md() macro sets the digest function used for
325 DSA parameter generation to B<md>. If not specified, one of SHA-1, SHA-224, or
326 SHA-256 is selected to match the bit length of B<q> above.
330 The EVP_PKEY_CTX_set_dh_paramgen_prime_len() macro sets the length of the DH
331 prime parameter B<p> for DH parameter generation. If this macro is not called
332 then 1024 is used. Only accepts lengths greater than or equal to 256.
334 The EVP_PKEY_CTX_set_dh_paramgen_subprime_len() macro sets the length of the DH
335 optional subprime parameter B<q> for DH parameter generation. The default is
336 256 if the prime is at least 2048 bits long or 160 otherwise. The DH
337 paramgen type must have been set to x9.42.
339 The EVP_PKEY_CTX_set_dh_paramgen_generator() macro sets DH generator to B<gen>
340 for DH parameter generation. If not specified 2 is used.
342 The EVP_PKEY_CTX_set_dh_paramgen_type() macro sets the key type for DH
343 parameter generation. Use 0 for PKCS#3 DH and 1 for X9.42 DH.
346 The EVP_PKEY_CTX_set_dh_pad() function sets the DH padding mode.
347 If B<pad> is 1 the shared secret is padded with zeroes up to the size of the DH
349 If B<pad> is zero (the default) then no padding is performed.
351 EVP_PKEY_CTX_set_dh_nid() sets the DH parameters to values corresponding to
352 B<nid> as defined in RFC7919. The B<nid> parameter must be B<NID_ffdhe2048>,
353 B<NID_ffdhe3072>, B<NID_ffdhe4096>, B<NID_ffdhe6144>, B<NID_ffdhe8192>
354 or B<NID_undef> to clear the stored value. This macro can be called during
355 parameter or key generation.
356 The nid parameter and the rfc5114 parameter are mutually exclusive.
358 The EVP_PKEY_CTX_set_dh_rfc5114() and EVP_PKEY_CTX_set_dhx_rfc5114() macros are
359 synonymous. They set the DH parameters to the values defined in RFC5114. The
360 B<rfc5114> parameter must be 1, 2 or 3 corresponding to RFC5114 sections
361 2.1, 2.2 and 2.3. or 0 to clear the stored value. This macro can be called
362 during parameter generation. The B<ctx> must have a key type of
364 The rfc5114 parameter and the nid parameter are mutually exclusive.
366 =head2 DH key derivation function parameters
368 Note that all of the following functions require that the B<ctx> parameter has
369 a private key type of B<EVP_PKEY_DHX>. When using key derivation, the output of
370 EVP_PKEY_derive() is the output of the KDF instead of the DH shared secret.
371 The KDF output is typically used as a Key Encryption Key (KEK) that in turn
372 encrypts a Content Encryption Key (CEK).
374 The EVP_PKEY_CTX_set_dh_kdf_type() macro sets the key derivation function type
375 to B<kdf> for DH key derivation. Possible values are B<EVP_PKEY_DH_KDF_NONE>
376 and B<EVP_PKEY_DH_KDF_X9_42> which uses the key derivation specified in RFC2631
377 (based on the keying algorithm described in X9.42). When using key derivation,
378 the B<kdf_oid>, B<kdf_md> and B<kdf_outlen> parameters must also be specified.
380 The EVP_PKEY_CTX_get_dh_kdf_type() macro gets the key derivation function type
381 for B<ctx> used for DH key derivation. Possible values are B<EVP_PKEY_DH_KDF_NONE>
382 and B<EVP_PKEY_DH_KDF_X9_42>.
384 The EVP_PKEY_CTX_set0_dh_kdf_oid() macro sets the key derivation function
385 object identifier to B<oid> for DH key derivation. This OID should identify
386 the algorithm to be used with the Content Encryption Key.
387 The library takes ownership of the object identifier so the caller should not
388 free the original memory pointed to by B<oid>.
390 The EVP_PKEY_CTX_get0_dh_kdf_oid() macro gets the key derivation function oid
391 for B<ctx> used for DH key derivation. The resulting pointer is owned by the
392 library and should not be freed by the caller.
394 The EVP_PKEY_CTX_set_dh_kdf_md() macro sets the key derivation function
395 message digest to B<md> for DH key derivation. Note that RFC2631 specifies
396 that this digest should be SHA1 but OpenSSL tolerates other digests.
398 The EVP_PKEY_CTX_get_dh_kdf_md() macro gets the key derivation function
399 message digest for B<ctx> used for DH key derivation.
401 The EVP_PKEY_CTX_set_dh_kdf_outlen() macro sets the key derivation function
402 output length to B<len> for DH key derivation.
404 The EVP_PKEY_CTX_get_dh_kdf_outlen() macro gets the key derivation function
405 output length for B<ctx> used for DH key derivation.
407 The EVP_PKEY_CTX_set0_dh_kdf_ukm() macro sets the user key material to
408 B<ukm> and its length to B<len> for DH key derivation. This parameter is optional
409 and corresponds to the partyAInfo field in RFC2631 terms. The specification
410 requires that it is 512 bits long but this is not enforced by OpenSSL.
411 The library takes ownership of the user key material so the caller should not
412 free the original memory pointed to by B<ukm>.
414 The EVP_PKEY_CTX_get0_dh_kdf_ukm() macro gets the user key material for B<ctx>.
415 The return value is the user key material length. The resulting pointer is owned
416 by the library and should not be freed by the caller.
420 The EVP_PKEY_CTX_set_ec_paramgen_curve_nid() sets the EC curve for EC parameter
421 generation to B<nid>. For EC parameter generation this macro must be called
422 or an error occurs because there is no default curve.
423 This function can also be called to set the curve explicitly when
424 generating an EC key.
426 The EVP_PKEY_CTX_set_ec_param_enc() macro sets the EC parameter encoding to
427 B<param_enc> when generating EC parameters or an EC key. The encoding can be
428 B<OPENSSL_EC_EXPLICIT_CURVE> for explicit parameters (the default in versions
429 of OpenSSL before 1.1.0) or B<OPENSSL_EC_NAMED_CURVE> to use named curve form.
430 For maximum compatibility the named curve form should be used. Note: the
431 B<OPENSSL_EC_NAMED_CURVE> value was added in OpenSSL 1.1.0; previous
432 versions should use 0 instead.
434 =head2 ECDH parameters
436 The EVP_PKEY_CTX_set_ecdh_cofactor_mode() macro sets the cofactor mode to
437 B<cofactor_mode> for ECDH key derivation. Possible values are 1 to enable
438 cofactor key derivation, 0 to disable it and -1 to clear the stored cofactor
439 mode and fallback to the private key cofactor mode.
441 The EVP_PKEY_CTX_get_ecdh_cofactor_mode() macro returns the cofactor mode for
442 B<ctx> used for ECDH key derivation. Possible values are 1 when cofactor key
443 derivation is enabled and 0 otherwise.
445 =head2 ECDH key derivation function parameters
447 The EVP_PKEY_CTX_set_ecdh_kdf_type() macro sets the key derivation function type
448 to B<kdf> for ECDH key derivation. Possible values are B<EVP_PKEY_ECDH_KDF_NONE>
449 and B<EVP_PKEY_ECDH_KDF_X9_63> which uses the key derivation specified in X9.63.
450 When using key derivation, the B<kdf_md> and B<kdf_outlen> parameters must
453 The EVP_PKEY_CTX_get_ecdh_kdf_type() macro returns the key derivation function
454 type for B<ctx> used for ECDH key derivation. Possible values are
455 B<EVP_PKEY_ECDH_KDF_NONE> and B<EVP_PKEY_ECDH_KDF_X9_63>.
457 The EVP_PKEY_CTX_set_ecdh_kdf_md() macro sets the key derivation function
458 message digest to B<md> for ECDH key derivation. Note that X9.63 specifies
459 that this digest should be SHA1 but OpenSSL tolerates other digests.
461 The EVP_PKEY_CTX_get_ecdh_kdf_md() macro gets the key derivation function
462 message digest for B<ctx> used for ECDH key derivation.
464 The EVP_PKEY_CTX_set_ecdh_kdf_outlen() macro sets the key derivation function
465 output length to B<len> for ECDH key derivation.
467 The EVP_PKEY_CTX_get_ecdh_kdf_outlen() macro gets the key derivation function
468 output length for B<ctx> used for ECDH key derivation.
470 The EVP_PKEY_CTX_set0_ecdh_kdf_ukm() macro sets the user key material to B<ukm>
471 for ECDH key derivation. This parameter is optional and corresponds to the
472 shared info in X9.63 terms. The library takes ownership of the user key material
473 so the caller should not free the original memory pointed to by B<ukm>.
475 The EVP_PKEY_CTX_get0_ecdh_kdf_ukm() macro gets the user key material for B<ctx>.
476 The return value is the user key material length. The resulting pointer is owned
477 by the library and should not be freed by the caller.
479 =head2 Other parameters
481 The EVP_PKEY_CTX_set1_id(), EVP_PKEY_CTX_get1_id() and EVP_PKEY_CTX_get1_id_len()
482 macros are used to manipulate the special identifier field for specific signature
483 algorithms such as SM2. The EVP_PKEY_CTX_set1_id() sets an ID pointed by B<id> with
484 the length B<id_len> to the library. The library takes a copy of the id so that
485 the caller can safely free the original memory pointed to by B<id>. The
486 EVP_PKEY_CTX_get1_id_len() macro returns the length of the ID set via a previous
487 call to EVP_PKEY_CTX_set1_id(). The length is usually used to allocate adequate
488 memory for further calls to EVP_PKEY_CTX_get1_id(). The EVP_PKEY_CTX_get1_id()
489 macro returns the previously set ID value to caller in B<id>. The caller should
490 allocate adequate memory space for the B<id> before calling EVP_PKEY_CTX_get1_id().
494 EVP_PKEY_CTX_set_params() returns 1 for success or 0 otherwise.
495 EVP_PKEY_CTX_settable_params() returns an OSSL_PARAM array on success or NULL on
497 It may also return NULL if there are no settable parameters available.
499 EVP_PKEY_CTX_set_signature_md(), EVP_PKEY_CTX_set_dh_pad(), EVP_PKEY_CTX_ctrl()
500 and its macros return a positive value for success and 0 or a negative value for
501 failure. In particular a return value of -2 indicates the operation is not
502 supported by the public key algorithm.
506 L<EVP_PKEY_CTX_new(3)>,
507 L<EVP_PKEY_encrypt(3)>,
508 L<EVP_PKEY_decrypt(3)>,
510 L<EVP_PKEY_verify(3)>,
511 L<EVP_PKEY_verify_recover(3)>,
512 L<EVP_PKEY_derive(3)>,
513 L<EVP_PKEY_keygen(3)>
518 EVP_PKEY_CTX_set1_id(), EVP_PKEY_CTX_get1_id() and EVP_PKEY_CTX_get1_id_len()
519 macros were added in 1.1.1, other functions were added in OpenSSL 1.0.0.
521 EVP_PKEY_CTX_get_signature_md(), EVP_PKEY_CTX_set_signature_md() and
522 EVP_PKEY_CTX_set_dh_pad() were macros in OpenSSL 1.1.1 and below. From OpenSSL
523 3.0 they are functions.
527 Copyright 2006-2018 The OpenSSL Project Authors. All Rights Reserved.
529 Licensed under the Apache License 2.0 (the "License"). You may not use
530 this file except in compliance with the License. You can obtain a copy
531 in the file LICENSE in the source distribution or at
532 L<https://www.openssl.org/source/license.html>.