Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
RAND_EGD(3)			    OpenSSL			   RAND_EGD(3)

NAME
       RAND_egd, RAND_egd_bytes, RAND_query_egd_bytes -	query entropy
       gathering daemon

SYNOPSIS
	#include <openssl/rand.h>

	int RAND_egd_bytes(const char *path, int num);
	int RAND_egd(const char	*path);

	int RAND_query_egd_bytes(const char *path, unsigned char *buf, int num);

DESCRIPTION
       On older	platforms without a good source	of randomness such as
       "/dev/urandom", it is possible to query an Entropy Gathering Daemon
       (EGD) over a local socket to obtain randomness and seed the OpenSSL
       RNG.  The protocol used is defined by the EGDs available	at
       <http://egd.sourceforge.net/> or	<http://prngd.sourceforge.net>.

       RAND_egd_bytes()	requests num bytes of randomness from an EGD at	the
       specified socket	path, and passes the data it receives into RAND_add().
       RAND_egd() is equivalent	to RAND_egd_bytes() with num set to 255.

       RAND_query_egd_bytes() requests num bytes of randomness from an EGD at
       the specified socket path, where	num must be less than 256.  If buf is
       NULL, it	is equivalent to RAND_egd_bytes().  If buf is not NULL,	then
       the data	is copied to the buffer	and RAND_add() is not called.

       OpenSSL can be configured at build time to try to use the EGD for
       seeding automatically.

RETURN VALUES
       RAND_egd() and RAND_egd_bytes() return the number of bytes read from
       the daemon on success, or -1 if the connection failed or	the daemon did
       not return enough data to fully seed the	PRNG.

       RAND_query_egd_bytes() returns the number of bytes read from the	daemon
       on success, or -1 if the	connection failed.

SEE ALSO
       RAND_add(3), RAND_bytes(3), RAND(7)

COPYRIGHT
       Copyright 2000-2018 The OpenSSL Project Authors.	All Rights Reserved.

       Licensed	under the OpenSSL license (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>.

1.1.1d				  2019-09-10			   RAND_EGD(3)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | SEE ALSO | COPYRIGHT

Want to link to this manual page? Use this URL:
<https://www.freebsd.org/cgi/man.cgi?query=RAND_egd&sektion=3&manpath=FreeBSD+12.1-RELEASE+and+Ports>

home | help