openssl (3.1.3)
Browse
Usage
VersionsRAND_LOAD_FILE(3ossl) OpenSSL RAND_LOAD_FILE(3ossl)
NAME
RAND_load_file, RAND_write_file, RAND_file_name - PRNG seed file
SYNOPSIS
#include <openssl/rand.h>
int RAND_load_file(const char *filename, long max_bytes);
int RAND_write_file(const char *filename);
const char *RAND_file_name(char *buf, size_t num);
DESCRIPTION
RAND_load_file() reads a number of bytes from file filename and adds them to the PRNG. If max_bytes is
nonnegative, up to max_bytes are read; if max_bytes is -1, the complete file is read. Do not load the same file
multiple times unless its contents have been updated by RAND_write_file() between reads. Also, note that
filename should be adequately protected so that an attacker cannot replace or examine the contents. If filename
is not a regular file, then user is considered to be responsible for any side effects, e.g. non-anticipated
blocking or capture of controlling terminal.
RAND_write_file() writes a number of random bytes (currently 128) to file filename which can be used to
initialize the PRNG by calling RAND_load_file() in a later session.
RAND_file_name() generates a default path for the random seed file. buf points to a buffer of size num in which
to store the filename.
On all systems, if the environment variable RANDFILE is set, its value will be used as the seed filename.
Otherwise, the file is called ".rnd", found in platform dependent locations:
On Windows (in order of preference)
%HOME%, %USERPROFILE%, %SYSTEMROOT%, C:\
On VMS
SYS$LOGIN:
On all other systems
$HOME
If $HOME (on non-Windows and non-VMS system) is not set either, or num is too small for the pathname, an error
occurs.
RETURN VALUES
RAND_load_file() returns the number of bytes read or -1 on error.
RAND_write_file() returns the number of bytes written, or -1 if the bytes written were generated without
appropriate seeding.
RAND_file_name() returns a pointer to buf on success, and NULL on error.
SEE ALSO
RAND_add(3), RAND_bytes(3), RAND(7)
COPYRIGHT
Copyright 2000-2020 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the Apache License 2.0 (the "License"). You may not use this file except in compliance with the
License. You can obtain a copy in the file LICENSE in the source distribution or at
<https://www.openssl.org/source/license.html>.
3.1.3 2023-09-19 RAND_LOAD_FILE(3ossl)
NAME
RAND_load_file, RAND_write_file, RAND_file_name - PRNG seed file
SYNOPSIS
#include <openssl/rand.h>
int RAND_load_file(const char *filename, long max_bytes);
int RAND_write_file(const char *filename);
const char *RAND_file_name(char *buf, size_t num);
DESCRIPTION
RAND_load_file() reads a number of bytes from file filename and adds them to the PRNG. If max_bytes is
nonnegative, up to max_bytes are read; if max_bytes is -1, the complete file is read. Do not load the same file
multiple times unless its contents have been updated by RAND_write_file() between reads. Also, note that
filename should be adequately protected so that an attacker cannot replace or examine the contents. If filename
is not a regular file, then user is considered to be responsible for any side effects, e.g. non-anticipated
blocking or capture of controlling terminal.
RAND_write_file() writes a number of random bytes (currently 128) to file filename which can be used to
initialize the PRNG by calling RAND_load_file() in a later session.
RAND_file_name() generates a default path for the random seed file. buf points to a buffer of size num in which
to store the filename.
On all systems, if the environment variable RANDFILE is set, its value will be used as the seed filename.
Otherwise, the file is called ".rnd", found in platform dependent locations:
On Windows (in order of preference)
%HOME%, %USERPROFILE%, %SYSTEMROOT%, C:\
On VMS
SYS$LOGIN:
On all other systems
$HOME
If $HOME (on non-Windows and non-VMS system) is not set either, or num is too small for the pathname, an error
occurs.
RETURN VALUES
RAND_load_file() returns the number of bytes read or -1 on error.
RAND_write_file() returns the number of bytes written, or -1 if the bytes written were generated without
appropriate seeding.
RAND_file_name() returns a pointer to buf on success, and NULL on error.
SEE ALSO
RAND_add(3), RAND_bytes(3), RAND(7)
COPYRIGHT
Copyright 2000-2020 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the Apache License 2.0 (the "License"). You may not use this file except in compliance with the
License. You can obtain a copy in the file LICENSE in the source distribution or at
<https://www.openssl.org/source/license.html>.
3.1.3 2023-09-19 RAND_LOAD_FILE(3ossl)