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			Update various RAND podpages
Reviewed-by: Tim Hudson <tjh@openssl.org> (Merged from https://github.com/openssl/openssl/pull/3883)
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				|  | @ -35,15 +35,13 @@ can be found in the literature; for example IETF RFC 4086. | ||||||
| RAND_add() may be called with sensitive data such as user entered | RAND_add() may be called with sensitive data such as user entered | ||||||
| passwords. The seed values cannot be recovered from the PRNG output. | passwords. The seed values cannot be recovered from the PRNG output. | ||||||
| 
 | 
 | ||||||
| OpenSSL makes sure that the PRNG state is unique for each thread. On |  | ||||||
| systems that provide C</dev/urandom>, the randomness device is used |  | ||||||
| to seed the PRNG transparently. However, on all other systems, the |  | ||||||
| application is responsible for seeding the PRNG by calling RAND_add(), |  | ||||||
| L<RAND_egd(3)> |  | ||||||
| or L<RAND_load_file(3)>. |  | ||||||
| 
 |  | ||||||
| RAND_seed() is equivalent to RAND_add() with B<randomness> set to B<num>. | RAND_seed() is equivalent to RAND_add() with B<randomness> set to B<num>. | ||||||
| 
 | 
 | ||||||
|  | On systems that provide C</dev/urandom> or similar source of randomess, | ||||||
|  | it will be used | ||||||
|  | to seed the PRNG transparently. On older systems, however, it might | ||||||
|  | be necessary to use RAND_add(), L<RAND_egd(3)> or L<RAND_load_file(3)>. | ||||||
|  | 
 | ||||||
| RAND_event() and RAND_screen() are deprecated and should not be called. | RAND_event() and RAND_screen() are deprecated and should not be called. | ||||||
| 
 | 
 | ||||||
| =head1 RETURN VALUES | =head1 RETURN VALUES | ||||||
|  | @ -65,11 +63,11 @@ RAND_event() and RAND_screen() are deprecated since OpenSSL | ||||||
| =head1 SEE ALSO | =head1 SEE ALSO | ||||||
| 
 | 
 | ||||||
| L<RAND_bytes(3)>, L<RAND_egd(3)>, | L<RAND_bytes(3)>, L<RAND_egd(3)>, | ||||||
| L<RAND_load_file(3)>, L<RAND_cleanup(3)> | L<RAND_load_file(3)> | ||||||
| 
 | 
 | ||||||
| =head1 COPYRIGHT | =head1 COPYRIGHT | ||||||
| 
 | 
 | ||||||
| Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved. | Copyright 2000-2017 The OpenSSL Project Authors. All Rights Reserved. | ||||||
| 
 | 
 | ||||||
| Licensed under the OpenSSL license (the "License").  You may not use | Licensed under the OpenSSL license (the "License").  You may not use | ||||||
| this file except in compliance with the License.  You can obtain a copy | this file except in compliance with the License.  You can obtain a copy | ||||||
|  |  | ||||||
|  | @ -14,9 +14,10 @@ RAND_cleanup - erase the PRNG state | ||||||
| 
 | 
 | ||||||
| =head1 DESCRIPTION | =head1 DESCRIPTION | ||||||
| 
 | 
 | ||||||
| Prior to OpenSSL 1.1.0 RAND_cleanup() erases the memory used by the PRNG. This | Prior to OpenSSL 1.1.0, RAND_cleanup() released all resources used by | ||||||
| function is deprecated and as of version 1.1.0 does nothing. No explicit | the PRNG.  As of version 1.1.0, it does nothing and should not be called, | ||||||
| initialisation or de-initialisation is necessary. See L<OPENSSL_init_crypto(3)>. | since since no explicit initialisation or de-initialisation is necessary. See | ||||||
|  | L<OPENSSL_init_crypto(3)>. | ||||||
| 
 | 
 | ||||||
| =head1 RETURN VALUE | =head1 RETURN VALUE | ||||||
| 
 | 
 | ||||||
|  | @ -32,7 +33,7 @@ RAND_cleanup() was deprecated in OpenSSL 1.1.0. | ||||||
| 
 | 
 | ||||||
| =head1 COPYRIGHT | =head1 COPYRIGHT | ||||||
| 
 | 
 | ||||||
| Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved. | Copyright 2000-2017 The OpenSSL Project Authors. All Rights Reserved. | ||||||
| 
 | 
 | ||||||
| Licensed under the OpenSSL license (the "License").  You may not use | Licensed under the OpenSSL license (the "License").  You may not use | ||||||
| this file except in compliance with the License.  You can obtain a copy | this file except in compliance with the License.  You can obtain a copy | ||||||
|  |  | ||||||
|  | @ -8,76 +8,48 @@ RAND_egd, RAND_egd_bytes, RAND_query_egd_bytes - query entropy gathering daemon | ||||||
| 
 | 
 | ||||||
|  #include <openssl/rand.h> |  #include <openssl/rand.h> | ||||||
| 
 | 
 | ||||||
|  |  int RAND_egd_bytes(const char *path, int num); | ||||||
|  int RAND_egd(const char *path); |  int RAND_egd(const char *path); | ||||||
|  int RAND_egd_bytes(const char *path, int bytes); |  | ||||||
| 
 | 
 | ||||||
|  int RAND_query_egd_bytes(const char *path, unsigned char *buf, int bytes); |  int RAND_query_egd_bytes(const char *path, unsigned char *buf, int num); | ||||||
| 
 | 
 | ||||||
| =head1 DESCRIPTION | =head1 DESCRIPTION | ||||||
| 
 | 
 | ||||||
| RAND_egd() queries the Entropy Gathering Daemon (EGD) on socket B<path>. | On older platforms without a good source of randomness such as C</dev/urandom>, | ||||||
| It queries 255 bytes and uses L<RAND_add(3)> to seed the | it is possible to query an Entropy Gathering Daemon (EGD) over a local | ||||||
| OpenSSL built-in PRNG. RAND_egd(path) is a wrapper for | socket to obtain randomness and seed the OpenSSL RNG. | ||||||
| RAND_egd_bytes(path, 255); | The protocol used is defined by the EGDs available at | ||||||
|  | L<http://egd.sourceforge.net/> or L<http://prngd.sourceforge.net>. | ||||||
| 
 | 
 | ||||||
| RAND_egd_bytes() queries EGD on socket B<path>. | RAND_egd_bytes() requests B<num> bytes of randomness from an EGD at the | ||||||
| It queries B<bytes> bytes and uses L<RAND_add(3)> to seed the | specified socket B<path>, and passes the data it receives into RAND_add(). | ||||||
| OpenSSL built-in PRNG. | RAND_egd() is equivalent to RAND_egd_bytes() with B<num> set to 255. | ||||||
| This function is more flexible than RAND_egd(). |  | ||||||
| When only one secret key must |  | ||||||
| be generated, it is not necessary to request the full amount 255 bytes from |  | ||||||
| the EGD socket. This can be advantageous, since the amount of randomness |  | ||||||
| that can be retrieved from EGD over time is limited. |  | ||||||
| 
 | 
 | ||||||
| RAND_query_egd_bytes() performs the actual query of the EGD daemon on socket | RAND_query_egd_bytes() requests B<num> bytes of randomness from an EGD at | ||||||
| B<path>. If B<buf> is given, B<bytes> bytes are queried and written into | the specified socket B<path>. | ||||||
| B<buf>. If B<buf> is NULL, B<bytes> bytes are queried and used to seed the | If B<buf> is B<NULL>, it is equivalent to RAND_egd_bytes(). | ||||||
| OpenSSL built-in PRNG using L<RAND_add(3)>. | If B<buf> is not B<NULL>, then the data is copied to the buffer and | ||||||
|  | RAND_add() is not called. | ||||||
| 
 | 
 | ||||||
| =head1 NOTES | OpenSSL can be configured at build time to try to use the EGD for seeding | ||||||
| 
 | automatically. | ||||||
| On systems without /dev/*random devices providing randomness from the kernel, |  | ||||||
| EGD provides |  | ||||||
| a socket interface through which randomness can be gathered in chunks up to |  | ||||||
| 255 bytes. Several chunks can be queried during one connection. |  | ||||||
| 
 |  | ||||||
| EGD is available from http://www.lothar.com/tech/crypto/ (C<perl |  | ||||||
| Makefile.PL; make; make install> to install). It is run as B<egd> |  | ||||||
| I<path>, where I<path> is an absolute path designating a socket. When |  | ||||||
| RAND_egd() is called with that path as an argument, it tries to read |  | ||||||
| random bytes that EGD has collected. RAND_egd() retrieves randomness from the |  | ||||||
| daemon using the daemon's "non-blocking read" command which shall |  | ||||||
| be answered immediately by the daemon without waiting for additional |  | ||||||
| randomness to be collected. The write and read socket operations in the |  | ||||||
| communication are blocking. |  | ||||||
| 
 |  | ||||||
| Alternatively, the EGD-interface compatible daemon PRNGD can be used. It is |  | ||||||
| available from |  | ||||||
| http://prngd.sourceforge.net/ . |  | ||||||
| PRNGD does employ an internal PRNG itself and can therefore never run |  | ||||||
| out of randomness. |  | ||||||
| 
 |  | ||||||
| OpenSSL automatically queries EGD when randomness is requested via RAND_bytes() |  | ||||||
| or the status is checked via RAND_status() for the first time, if the socket |  | ||||||
| is located at /var/run/egd-pool, /dev/egd-pool or /etc/egd-pool. |  | ||||||
| 
 | 
 | ||||||
| =head1 RETURN VALUE | =head1 RETURN VALUE | ||||||
| 
 | 
 | ||||||
| RAND_egd() and RAND_egd_bytes() return the number of bytes read from the | RAND_egd() and RAND_egd_bytes() return the number of bytes read from the | ||||||
| daemon on success, and -1 if the connection failed or the daemon did not | daemon on success, or -1 if the connection failed or the daemon did not | ||||||
| return enough data to fully seed the PRNG. | return enough data to fully seed the PRNG. | ||||||
| 
 | 
 | ||||||
| RAND_query_egd_bytes() returns the number of bytes read from the daemon on | RAND_query_egd_bytes() returns the number of bytes read from the daemon on | ||||||
| success, and -1 if the connection failed. The PRNG state is not considered. | success, or -1 if the connection failed. | ||||||
| 
 | 
 | ||||||
| =head1 SEE ALSO | =head1 SEE ALSO | ||||||
| 
 | 
 | ||||||
| L<RAND_bytes(3)>, L<RAND_add(3)>, | L<RAND_bytes(3)>, L<RAND_add(3)> | ||||||
| L<RAND_cleanup(3)> |  | ||||||
| 
 | 
 | ||||||
| =head1 COPYRIGHT | =head1 COPYRIGHT | ||||||
| 
 | 
 | ||||||
| Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved. | Copyright 2000-2017 The OpenSSL Project Authors. All Rights Reserved. | ||||||
| 
 | 
 | ||||||
| Licensed under the OpenSSL license (the "License").  You may not use | Licensed under the OpenSSL license (the "License").  You may not use | ||||||
| this file except in compliance with the License.  You can obtain a copy | this file except in compliance with the License.  You can obtain a copy | ||||||
|  |  | ||||||
|  | @ -64,7 +64,7 @@ error. | ||||||
| 
 | 
 | ||||||
| =head1 SEE ALSO | =head1 SEE ALSO | ||||||
| 
 | 
 | ||||||
| L<RAND_bytes(3)>, L<RAND_add(3)>, L<RAND_cleanup(3)> | L<RAND_bytes(3)>, L<RAND_add(3)> | ||||||
| 
 | 
 | ||||||
| =head1 HISTORY | =head1 HISTORY | ||||||
| 
 | 
 | ||||||
|  | @ -75,7 +75,7 @@ poorly enforced before OpenSSL version 1.1.1. | ||||||
| 
 | 
 | ||||||
| =head1 COPYRIGHT | =head1 COPYRIGHT | ||||||
| 
 | 
 | ||||||
| Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved. | Copyright 2000-2017 The OpenSSL Project Authors. All Rights Reserved. | ||||||
| 
 | 
 | ||||||
| Licensed under the OpenSSL license (the "License").  You may not use | Licensed under the OpenSSL license (the "License").  You may not use | ||||||
| this file except in compliance with the License.  You can obtain a copy | this file except in compliance with the License.  You can obtain a copy | ||||||
|  |  | ||||||
|  | @ -8,35 +8,32 @@ RAND_set_rand_method, RAND_get_rand_method, RAND_OpenSSL - select RAND method | ||||||
| 
 | 
 | ||||||
|  #include <openssl/rand.h> |  #include <openssl/rand.h> | ||||||
| 
 | 
 | ||||||
|  |  RAND_METHOD *RAND_OpenSSL(void); | ||||||
|  | 
 | ||||||
|  void RAND_set_rand_method(const RAND_METHOD *meth); |  void RAND_set_rand_method(const RAND_METHOD *meth); | ||||||
| 
 | 
 | ||||||
|  const RAND_METHOD *RAND_get_rand_method(void); |  const RAND_METHOD *RAND_get_rand_method(void); | ||||||
| 
 | 
 | ||||||
|  RAND_METHOD *RAND_OpenSSL(void); |  | ||||||
| 
 |  | ||||||
| =head1 DESCRIPTION | =head1 DESCRIPTION | ||||||
| 
 | 
 | ||||||
| A B<RAND_METHOD> specifies the functions that OpenSSL uses for random number | A B<RAND_METHOD> specifies the functions that OpenSSL uses for random number | ||||||
| generation. By modifying the method, alternative implementations such as | generation. | ||||||
| hardware RNGs may be used. IMPORTANT: See the NOTES section for important |  | ||||||
| information about how these RAND API functions are affected by the use of |  | ||||||
| B<ENGINE> API calls. |  | ||||||
| 
 | 
 | ||||||
| Initially, the default RAND_METHOD is the OpenSSL internal implementation, as | Initially, the default B<RAND_METHOD> is the OpenSSL internal implementation, | ||||||
| returned by RAND_OpenSSL(). | as returned by RAND_OpenSSL(). | ||||||
|  | This implementation ensures that the PRNG state is unique for each thread. | ||||||
| 
 | 
 | ||||||
| RAND_set_default_method() makes B<meth> the method for PRNG use. B<NB>: This is | If an B<ENGINE> is loaded that provides the RAND API, however, it will | ||||||
| true only whilst no ENGINE has been set as a default for RAND, so this function | be used instead of the method returned by RAND_OpenSSL(). | ||||||
| is no longer recommended. |  | ||||||
| 
 | 
 | ||||||
| RAND_get_default_method() returns a pointer to the current RAND_METHOD. | RAND_set_rand_method() makes B<meth> the method for PRNG use.  If an | ||||||
| However, the meaningfulness of this result is dependent on whether the ENGINE | ENGINE was providing the method, it will be released first. | ||||||
| API is being used, so this function is no longer recommended. | 
 | ||||||
|  | RAND_get_rand_method() returns a pointer to the current B<RAND_METHOD>. | ||||||
| 
 | 
 | ||||||
| =head1 THE RAND_METHOD STRUCTURE | =head1 THE RAND_METHOD STRUCTURE | ||||||
| 
 | 
 | ||||||
|  typedef struct rand_meth_st |  typedef struct rand_meth_st { | ||||||
|  { |  | ||||||
|      void (*seed)(const void *buf, int num); |      void (*seed)(const void *buf, int num); | ||||||
|      int (*bytes)(unsigned char *buf, int num); |      int (*bytes)(unsigned char *buf, int num); | ||||||
|      void (*cleanup)(void); |      void (*cleanup)(void); | ||||||
|  | @ -45,33 +42,23 @@ API is being used, so this function is no longer recommended. | ||||||
|      int (*status)(void); |      int (*status)(void); | ||||||
|  } RAND_METHOD; |  } RAND_METHOD; | ||||||
| 
 | 
 | ||||||
| The components point to method implementations used by (or called by), in order, | The fields point to functions that are used by, in order, | ||||||
| RAND_seed(), RAND_bytes(), internal RAND cleanup, RAND_add(), RAND_pseudo_rand() | RAND_seed(), RAND_bytes(), internal RAND cleanup, RAND_add(), RAND_pseudo_rand() | ||||||
| and RAND_status(). | and RAND_status(). | ||||||
| Each component may be NULL if the function is not implemented. | Each pointer may be NULL if the function is not implemented. | ||||||
| 
 | 
 | ||||||
| =head1 RETURN VALUES | =head1 RETURN VALUES | ||||||
| 
 | 
 | ||||||
| RAND_set_rand_method() returns no value. RAND_get_rand_method() and | RAND_set_rand_method() returns no value. RAND_get_rand_method() and | ||||||
| RAND_OpenSSL() return pointers to the respective methods. | RAND_OpenSSL() return pointers to the respective methods. | ||||||
| 
 | 
 | ||||||
| =head1 NOTES |  | ||||||
| 
 |  | ||||||
| RAND_METHOD implementations are grouped together with other |  | ||||||
| algorithmic APIs (eg. RSA_METHOD, EVP_CIPHER, etc) in B<ENGINE> modules. If a |  | ||||||
| default ENGINE is specified for RAND functionality using an ENGINE API function, |  | ||||||
| that will override any RAND defaults set using the RAND API (ie. |  | ||||||
| RAND_set_rand_method()). For this reason, the ENGINE API is the recommended way |  | ||||||
| to control default implementations for use in RAND and other cryptographic |  | ||||||
| algorithms. |  | ||||||
| 
 |  | ||||||
| =head1 SEE ALSO | =head1 SEE ALSO | ||||||
| 
 | 
 | ||||||
| L<RAND_bytes(3)>, L<ENGINE_by_id(3)> | L<RAND_bytes(3)>, L<ENGINE_by_id(3)> | ||||||
| 
 | 
 | ||||||
| =head1 COPYRIGHT | =head1 COPYRIGHT | ||||||
| 
 | 
 | ||||||
| Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved. | Copyright 2000-2017 The OpenSSL Project Authors. All Rights Reserved. | ||||||
| 
 | 
 | ||||||
| Licensed under the OpenSSL license (the "License").  You may not use | Licensed under the OpenSSL license (the "License").  You may not use | ||||||
| this file except in compliance with the License.  You can obtain a copy | this file except in compliance with the License.  You can obtain a copy | ||||||
|  |  | ||||||
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