Automatically generated by Pod::Man 4.14 (Pod::Simple 3.42)

Standard preamble:
========================================================================
..

..

.. Set up some character translations and predefined strings. \*(-- will
give an unbreakable dash, \*(PI will give pi, \*(L" will give a left
double quote, and \*(R" will give a right double quote. \*(C+ will
give a nicer C++. Capital omega is used to do unbreakable dashes and
therefore won't be available. \*(C` and \*(C' expand to `' in nroff,
nothing in troff, for use with C<>.
.tr \(*W- . ds -- \(*W- . ds PI pi . if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch . if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch . ds L" "" . ds R" "" . ds C` "" . ds C' "" 'br\} . ds -- \|\(em\| . ds PI \(*p . ds L" `` . ds R" '' . ds C` . ds C' 'br\}
Escape single quotes in literal strings from groff's Unicode transform.

If the F register is >0, we'll generate index entries on stderr for
titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index
entries marked with X<> in POD. Of course, you'll have to process the
output yourself in some meaningful fashion.

Avoid warning from groff about undefined register 'F'.
.. .nr rF 0 . if \nF \{\ . de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . if !\nF==2 \{\ . nr % 0 . nr F 2 . \} . \} .\} .rr rF
Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2).
Fear. Run. Save yourself. No user-serviceable parts.
. \" fudge factors for nroff and troff . ds #H 0 . ds #V .8m . ds #F .3m . ds #[ \f1 . ds #] .\} . ds #H ((1u-(\\\\n(.fu%2u))*.13m) . ds #V .6m . ds #F 0 . ds #[ \& . ds #] \& .\} . \" simple accents for nroff and troff . ds ' \& . ds ` \& . ds ^ \& . ds , \& . ds ~ ~ . ds / .\} . ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u" . ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u' . ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u' . ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u' . ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u' . ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u' .\} . \" troff and (daisy-wheel) nroff accents . \" corrections for vroff . \" for low resolution devices (crt and lpr) \{\ . ds : e . ds 8 ss . ds o a . ds d- d\h'-1'\(ga . ds D- D\h'-1'\(hy . ds th \o'bp' . ds Th \o'LP' . ds ae ae . ds Ae AE .\} ========================================================================

Title "EVP_PKEY-DSA 7ossl" For nroff, turn off justification. Always turn off hyphenation; it makes
way too many mistakes in technical documents.
EVP_PKEY-DSA, EVP_KEYMGMT-DSA - EVP_PKEY DSA keytype and algorithm support Header "DESCRIPTION" For \s-1DSA\s0 the \s-1FIPS186-4\s0 standard specifies that the values used for \s-1FFC\s0 parameter generation are also required for parameter validation. This means that optional \s-1FFC\s0 domain parameter values for seed, pcounter and gindex may need to be stored for validation purposes. For \s-1DSA\s0 these fields are not stored in the \s-1ASN1\s0 data so they need to be stored externally if validation is required. Subsection "DSA parameters" The \s-1DSA\s0 key type supports the \s-1FFC\s0 parameters (see \*(L"\s-1FFC\s0 parameters\*(R" in \s-1EVP_PKEY-FFC\s0\|(7)). Subsection "DSA key generation parameters" The \s-1DSA\s0 key type supports the \s-1FFC\s0 key generation parameters (see \*(L"\s-1FFC\s0 key generation parameters\*(R" in \s-1EVP_PKEY-FFC\s0\|(7)

The following restrictions apply to the \*(L"pbits\*(R" field:

For \*(L"fips186_4\*(R" this must be either 2048 or 3072. For \*(L"fips186_2\*(R" this must be 1024. For \*(L"group\*(R" this can be any one of 2048, 3072, 4096, 6144 or 8192.

Subsection "DSA key validation" For \s-1DSA\s0 keys, EVP_PKEY_param_check\|(3) behaves in the following way: The OpenSSL \s-1FIPS\s0 provider conforms to the rules within the \s-1FIPS186-4\s0 standard for \s-1FFC\s0 parameter validation. For backwards compatibility the OpenSSL default provider uses a much simpler check (see below) for parameter validation, unless the seed parameter is set.

For \s-1DSA\s0 keys, EVP_PKEY_param_check_quick\|(3) behaves in the following way: A simple check of L and N and partial g is performed. The default provider also supports validation of legacy \*(L"fips186_2\*(R" keys.

For \s-1DSA\s0 keys, EVP_PKEY_public_check\|(3), EVP_PKEY_private_check\|(3) and \fBEVP_PKEY_pairwise_check\|(3) the OpenSSL default and \s-1FIPS\s0 providers conform to the rules within SP800-56Ar3 for public, private and pairwise tests respectively.

Header "EXAMPLES" An \s-1EVP_PKEY\s0 context can be obtained by calling:

.Vb 1 EVP_PKEY_CTX *pctx = EVP_PKEY_CTX_new_from_name(NULL, "DSA", NULL); .Ve

The \s-1DSA\s0 domain parameters can be generated by calling:

.Vb 6 unsigned int pbits = 2048; unsigned int qbits = 256; int gindex = 1; OSSL_PARAM params[5]; EVP_PKEY *param_key = NULL; EVP_PKEY_CTX *pctx = NULL; \& pctx = EVP_PKEY_CTX_new_from_name(NULL, "DSA", NULL); EVP_PKEY_paramgen_init(pctx); \& params[0] = OSSL_PARAM_construct_uint("pbits", &pbits); params[1] = OSSL_PARAM_construct_uint("qbits", &qbits); params[2] = OSSL_PARAM_construct_int("gindex", &gindex); params[3] = OSSL_PARAM_construct_utf8_string("digest", "SHA384", 0); params[4] = OSSL_PARAM_construct_end(); EVP_PKEY_CTX_set_params(pctx, params); \& EVP_PKEY_generate(pctx, &param_key); EVP_PKEY_CTX_free(pctx); \& EVP_PKEY_print_params(bio_out, param_key, 0, NULL); .Ve

A \s-1DSA\s0 key can be generated using domain parameters by calling:

.Vb 2 EVP_PKEY *key = NULL; EVP_PKEY_CTX *gctx = NULL; \& gctx = EVP_PKEY_CTX_new_from_pkey(NULL, param_key, NULL); EVP_PKEY_keygen_init(gctx); EVP_PKEY_generate(gctx, &key); EVP_PKEY_CTX_free(gctx); EVP_PKEY_print_private(bio_out, key, 0, NULL); .Ve

Header "CONFORMING TO" The following sections of \s-1FIPS186-4:\s0 Item "A.1.1.2 Generation of Probable Primes p and q Using an Approved Hash Function."

0

Item "A.2.3 Generation of canonical generator g." Item "A.2.1 Unverifiable Generation of the Generator g."

Header "SEE ALSO" \s-1EVP_PKEY-FFC\s0\|(7), \s-1EVP_SIGNATURE-DSA\s0\|(7) \s-1EVP_PKEY\s0\|(3), \fBprovider-keymgmt\|(7), \s-1EVP_KEYMGMT\s0\|(3), \fBOSSL_PROVIDER-default\|(7), \s-1OSSL_PROVIDER-FIPS\s0\|(7) Header "COPYRIGHT" Copyright 2020-2022 The OpenSSL Project Authors. All Rights Reserved.

Licensed under the Apache License 2.0 (the \*(L"License\*(R"). You may not use this file except in compliance with the License. You can obtain a copy in the file \s-1LICENSE\s0 in the source distribution or at <https://www.openssl.org/source/license.html>.