xref: /freebsd/secure/lib/libcrypto/man/man3/RAND_set_rand_method.3 (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
Automatically generated by Pod::Man 4.14 (Pod::Simple 3.40)

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 "RAND_SET_RAND_METHOD 3"
RAND_SET_RAND_METHOD 3 "2023-08-01" "3.0.10" "OpenSSL"
For nroff, turn off justification. Always turn off hyphenation; it makes
way too many mistakes in technical documents.
"NAME"
RAND_set_rand_method, RAND_get_rand_method, RAND_OpenSSL - select RAND method
"SYNOPSIS"
Header "SYNOPSIS" .Vb 1 #include <openssl/rand.h> .Ve

The following functions have been deprecated since OpenSSL 3.0, and can be hidden entirely by defining \s-1OPENSSL_API_COMPAT\s0 with a suitable version value, see openssl_user_macros\|(7):

.Vb 1 RAND_METHOD *RAND_OpenSSL(void); \& int RAND_set_rand_method(const RAND_METHOD *meth); \& const RAND_METHOD *RAND_get_rand_method(void); .Ve

"DESCRIPTION"
Header "DESCRIPTION" All of the functions described on this page are deprecated. Applications should instead use RAND_set_DRBG_type\|(3), \s-1EVP_RAND\s0\|(3) and \s-1EVP_RAND\s0\|(7).

A \s-1RAND_METHOD\s0 specifies the functions that OpenSSL uses for random number generation.

\fBRAND_OpenSSL() returns the default \s-1RAND_METHOD\s0 implementation by OpenSSL. This implementation ensures that the \s-1PRNG\s0 state is unique for each thread.

If an \s-1ENGINE\s0 is loaded that provides the \s-1RAND API,\s0 however, it will be used instead of the method returned by RAND_OpenSSL(). This is deprecated in OpenSSL 3.0.

\fBRAND_set_rand_method() makes meth the method for \s-1PRNG\s0 use. If an \s-1ENGINE\s0 was providing the method, it will be released first.

\fBRAND_get_rand_method() returns a pointer to the current \s-1RAND_METHOD\s0.

"THE RAND_METHOD STRUCTURE"
Header "THE RAND_METHOD STRUCTURE" .Vb 8 typedef struct rand_meth_st { int (*seed)(const void *buf, int num); int (*bytes)(unsigned char *buf, int num); void (*cleanup)(void); int (*add)(const void *buf, int num, double entropy); int (*pseudorand)(unsigned char *buf, int num); int (*status)(void); } RAND_METHOD; .Ve

The fields point to functions that are used by, in order, \fBRAND_seed(), RAND_bytes(), internal \s-1RAND\s0 cleanup, RAND_add(), RAND_pseudo_rand() and RAND_status(). Each pointer may be \s-1NULL\s0 if the function is not implemented.

"RETURN VALUES"
Header "RETURN VALUES" \fBRAND_set_rand_method() returns 1 on success and 0 on failure. \fBRAND_get_rand_method() and RAND_OpenSSL() return pointers to the respective methods.
"SEE ALSO"
Header "SEE ALSO" \s-1EVP_RAND\s0\|(3), \fBRAND_set_DRBG_type\|(3), \fBRAND_bytes\|(3), \fBENGINE_by_id\|(3), \s-1EVP_RAND\s0\|(7), \s-1RAND\s0\|(7)
"HISTORY"
Header "HISTORY" All of these functions were deprecated in OpenSSL 3.0.
"COPYRIGHT"
Header "COPYRIGHT" Copyright 2000-2021 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>.