Commit graph

635 commits

Author SHA1 Message Date
Richard Levitte
fcd2d5a612 Refactor the computation of API version limits
Previously, the API version limit was indicated with a numeric version
number.  This was "natural" in the pre-3.0.0 because the version was
this simple number.

With 3.0.0, the version is divided into three separate numbers, and
it's only the major number that counts, but we still need to be able
to support pre-3.0.0 version limits.

Therefore, we allow OPENSSL_API_COMPAT to be defined with a pre-3.0.0
style numeric version number or with a simple major number, i.e. can
be defined like this for any application:

    -D OPENSSL_API_COMPAT=0x10100000L
    -D OPENSSL_API_COMPAT=3

Since the pre-3.0.0 numerical version numbers are high, it's easy to
distinguish between a simple major number and a pre-3.0.0 numerical
version number and to thereby support both forms at the same time.

Internally, we define the following macros depending on the value of
OPENSSL_API_COMPAT:

    OPENSSL_API_0_9_8
    OPENSSL_API_1_0_0
    OPENSSL_API_1_1_0
    OPENSSL_API_3

They indicate that functions marked for deprecation in the
corresponding major release shall not be built if defined.

Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/7724)
2018-12-06 12:24:48 +01:00
Bernd Edlinger
e2d227bb4a Fix issues with do_rand_init/rand_cleanup_int
Fixes #7022

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7588)
2018-11-09 13:34:48 +01:00
Dr. Matthias St. Pierre
8cfc19716c rand_unix.c: open random devices on first use only
Commit c7504aeb64 (pr #6432) fixed a regression for applications in
chroot environments, which compensated the fact that the new OpenSSL CSPRNG
(based on the NIST DRBG) now reseeds periodically, which the previous
one didn't. Now the reseeding could fail in the chroot environment if the
DEVRANDOM devices were not present anymore and no other entropy source
(e.g. getrandom()) was available.

The solution was to keep the file handles for the DEVRANDOM devices open
by default. In fact, the fix did more than this, it opened the DEVRANDOM
devices early and unconditionally in rand_pool_init(), which had the
unwanted side effect that the devices were opened (and kept open) even
in cases when they were not used at all, for example when the getrandom()
system call was available. Due  to a bug (issue #7419) this even happened
when the feature was disabled by the application.

This commit removes the unconditional opening of all DEVRANDOM devices.
They will now only be opened (and kept open) on first use. In particular,
if getrandom() is available, the handles will not be opened unnecessarily.

This change does not introduce a regression for applications compiled for
libcrypto 1.1.0, because the SSLEAY RNG also seeds on first use. So in the
above constellation the CSPRNG will only be properly seeded if it is happens
before the forking and chrooting.

Fixes #7419

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7437)
2018-11-08 16:38:26 +01:00
Dr. Matthias St. Pierre
1c615e4ce9 Test: link drbgtest statically against libcrypto
and remove duplicate rand_drbg_seedlen() implementation again.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/7462)
2018-11-08 16:27:06 +01:00
Pauli
ac765685d4 Add missing RAND initialisation call.
Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
(Merged from https://github.com/openssl/openssl/pull/7587)
2018-11-08 07:22:01 +10:00
Bernd Edlinger
31f32abb8e Rename the rand_drbg_st data member "pool" to "seed_pool"
... to make the intended use more clear and differentiate
it from the data member "adin_pool".

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7575)
2018-11-07 15:21:24 +01:00
Bernd Edlinger
fb9c3ff565 Fix error handling in RAND_DRBG_uninstantiate
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7517)
2018-11-05 22:35:11 +01:00
Bernd Edlinger
c5e0b3a6d5 Fix error handling in rand_drbg_new
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7517)
2018-11-05 22:35:10 +01:00
Bernd Edlinger
17209be89b Fix error handling in RAND_DRBG_set
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7517)
2018-11-05 22:35:09 +01:00
Bernd Edlinger
54f3e855d4 Avoid two memory allocations in each RAND_DRBG_bytes
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7507)
2018-11-01 09:02:12 +10:00
Bernd Edlinger
4011bab1f8 Fix a race condition in drbg_add
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7523)
2018-10-30 23:25:30 +01:00
Bernd Edlinger
f9e43929c4 Rework and simplify resource flow in drbg_add
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7504)
2018-10-29 12:11:57 +01:00
Dr. Matthias St. Pierre
040a03470c randfile.c: fix a Coverity warning
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/7510)
2018-10-28 23:35:20 +01:00
Dr. Matthias St. Pierre
59f90557dd drbg_lib: avoid NULL pointer dereference in drbg_add
Found by Coverity Scan

Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/7511)
2018-10-28 19:19:17 +01:00
Bernd Edlinger
a83dc59afa Fix data race in RAND_DRBG_generate
Fixes #7394

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7399)
2018-10-26 15:33:37 +02:00
Bernd Edlinger
21311777ad Fix a possible crash in rand_drbg_get_entropy
Reviewed-by: Paul Yang <yang.yang@baishancloud.com>
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7474)
2018-10-26 15:14:55 +02:00
Dr. Matthias St. Pierre
8817215d5c RAND_add()/RAND_seed(): fix failure on short input or low entropy
Commit 5b4cb385c1 (#7382) introduced a bug which had the effect
that RAND_add()/RAND_seed() failed for buffer sizes less than
32 bytes. The reason was that now the added random data was used
exlusively as entropy source for reseeding. When the random input
was too short or contained not enough entropy, the DRBG failed
without querying the available entropy sources.

This commit makes drbg_add() act smarter: it checks the entropy
requirements explicitely. If the random input fails this check,
it won't be added as entropy input, but only as additional data.
More precisely, the behaviour depends on whether an os entropy
source was configured (which is the default on most os):

- If an os entropy source is avaible then we declare the buffer
  content as additional data by setting randomness to zero and
  trigger a regular   reseeding.

- If no os entropy source is available, a reseeding will fail
  inevitably. So drbg_add() uses a trick to mix the buffer contents
  into the DRBG state without forcing a reseeding: it generates a
  dummy random byte, using the buffer content as additional data.

Related-to: #7449

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7456)
2018-10-26 08:38:19 +02:00
Dr. Matthias St. Pierre
6ec6448b93 RAND_load_file(): avoid adding small chunks to RAND_add()
Increase the load buffer size such that it exceeds the chunk
size by a comfortable amount. This is done to avoid calling
RAND_add() with a small final chunk. Instead, such a small
final chunk will be added together with the previous chunk
(unless it's the only one).

Related-to: #7449

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7456)
2018-10-26 08:38:08 +02:00
Dr. Matthias St. Pierre
ec2d099fcc RAND_load_file(): return error if reseeding failed
The failure of RAND_load_file was only noticed because of the
heap corruption which was reported in #7499 and fixed in commit
5b4cb385c1. To prevent this in the future, RAND_load_file()
now explicitly checks RAND_status() and reports an error if it
fails.

Related-to: #7449

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7456)
2018-10-26 08:37:40 +02:00
Richard Levitte
f81b043ad8 RAND: ensure INT32_MAX is defined
This value is used to set DRBG_MAX_LENGTH

Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/7467)
2018-10-23 10:56:07 +02:00
Dr. Matthias St. Pierre
5b4cb385c1 RAND_add(): fix heap corruption in error path
This bug was introduced by #7382 which enhanced RAND_add() to
accept large buffer sizes. As a consequence, RAND_add() now fails
for buffer sizes less than 32 bytes (i.e. less than 256 bits).
In addition, rand_drbg_get_entropy() forgets to reset the attached
drbg->pool in the case of an error, which leads to the heap corruption.

The problem occurred with RAND_load_file(), which reads the file in
chunks of 1024 bytes each. If the size of the final chunk is less than
32 bytes, then RAND_add() fails, whence RAND_load_file() fails
silently for buffer sizes n = k * 1024 + r with r = 1,...,31.

This commit fixes the heap corruption only. The other issues will
be addressed in a separate pull request.

Thanks to Gisle Vanem for reporting this issue.

Fixes #7449

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7455)
2018-10-22 14:54:55 +02:00
Dr. Matthias St. Pierre
3064b55134 DRBG: fix reseeding via RAND_add()/RAND_seed() with large input
In pull request #4328 the seeding of the DRBG via RAND_add()/RAND_seed()
was implemented by buffering the data in a random pool where it is
picked up later by the rand_drbg_get_entropy() callback. This buffer
was limited to the size of 4096 bytes.

When a larger input was added via RAND_add() or RAND_seed() to the DRBG,
the reseeding failed, but the error returned by the DRBG was ignored
by the two calling functions, which both don't return an error code.
As a consequence, the data provided by the application was effectively
ignored.

This commit fixes the problem by a more efficient implementation which
does not copy the data in memory and by raising the buffer the size limit
to INT32_MAX (2 gigabytes). This is less than the NIST limit of 2^35 bits
but it was chosen intentionally to avoid platform dependent problems
like integer sizes and/or signed/unsigned conversion.

Additionally, the DRBG is now less permissive on errors: In addition to
pushing a message to the openssl error stack, it enters the error state,
which forces a reinstantiation on next call.

Thanks go to Dr. Falko Strenzke for reporting this issue to the
openssl-security mailing list. After internal discussion the issue
has been categorized as not being security relevant, because the DRBG
reseeds automatically and is fully functional even without additional
randomness provided by the application.

Fixes #7381

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7382)
2018-10-16 22:15:43 +02:00
FdaSilvaYY
c2e33a05b1 crypto/rand: fix some style nit's
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/7378)
2018-10-10 14:00:43 +02:00
Dr. Matthias St. Pierre
d90e128be6 rand_unix.c: fix --with-rand-seed=none build
Fixes a compiler warning about an unused syscall_random()
and cleans up the OPENSSL_RAND_SEED preprocessor logic.

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/779)
2018-10-10 12:39:03 +02:00
Shane Lontis
8bf3665196 Added DRBG_HMAC & DRBG_HASH + Added defaults for setting DRBG for master/public/private + renamed generate_counter back to reseed_counter + generated new cavs data tests
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/6779)
2018-09-28 07:22:13 +10:00
Pauli
5c39a55d04 Use secure_getenv(3) when available.
Change all calls to getenv() inside libcrypto to use a new wrapper function
that use secure_getenv() if available and an issetugid then getenv if not.

CPU processor override flags are unchanged.

Extra checks for OPENSSL_issetugid() have been removed in favour of the
safe getenv.

Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
(Merged from https://github.com/openssl/openssl/pull/7047)
2018-09-24 11:21:18 +10:00
Richard Levitte
cd92d1fdd3 VMS: only use the high precision on VMS v8.4 and up
It simply isn't available on older versions.

Issue submitted by Mark Daniels

Fixes #7229

Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/7230)

(cherry picked from commit d6d6aa3521)
2018-09-15 15:44:45 +02:00
Dr. Matthias St. Pierre
c402e943cd Replace the public RAND_DRBG_USED_FLAGS #define by an internal constant
The new DRBG API added the aforementioned #define. However, it is
used internally only and having it defined publicly does not serve
any purpose except causing potential version compatibility problems.

Fixes #7182

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7190)
2018-09-12 23:36:18 +02:00
Dr. Matthias St. Pierre
bc420ebea2 rand_lib.c: Don't open random devices while cleaning up.
Fixes #7022

In pull request #6432 a change was made to keep the handles to the
random devices opened in order to avoid reseeding problems for
applications in chroot environments.

As a consequence, the handles of the random devices were leaked at exit
if the random generator was not used by the application. This happened,
because the call to RAND_set_rand_method(NULL) in rand_cleanup_int()
triggered a call to the call_once function do_rand_init, which opened
the random devices via rand_pool_init().

Thanks to GitHub user @bwelling for reporting this issue.

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7023)
2018-08-22 10:53:49 +02:00
Dr. Matthias St. Pierre
cca9962178 rand_unix.c: don't discard entropy bytes from /dev/*random
Don't discard partial reads from /dev/*random and retry instead.

Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Tim Hudson <tjh@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6990)
2018-08-19 12:44:05 +02:00
Dr. Matthias St. Pierre
630ce41e83 rand_unix.c: don't discard entropy bytes from syscall_random()
Fixes #6978

Don't discard partial reads from syscall_random() and retry instead.

Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Tim Hudson <tjh@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6990)
2018-08-19 12:44:05 +02:00
Dr. Matthias St. Pierre
9b5f1c8fd8 rand_unix.c: assimilate syscall_random() with getrandom(2)
Change return value type to ssize_t and ensure that a negative value
is returned only if a corresponding errno is set.

Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Tim Hudson <tjh@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6990)
2018-08-19 12:44:05 +02:00
Shane Lontis
7c226dfc43 Fixed issue where DRBG_CTR fails if NO_DF is used - when entropy is called
Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/6778)
2018-07-26 06:58:44 +10:00
Andy Polyakov
a0e53000a8 rand/rand_unix.c: address macro redifinition warning.
Occasionally, e.g. when compiling for elderly glibc, you end up passing
-D_GNU_SOURCE on command line, and doing so triggered warning...

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6616)
2018-07-01 12:05:54 +02:00
Pauli
c7504aeb64 Modify the DEVRANDOM source so that the files are kept open persistently.
This allows operation inside a chroot environment without having the
random device present.

A new call, RAND_keep_random_devices_open(), has been introduced that can
be used to control file descriptor use by the random seed sources. Some
seed sources maintain open file descriptors by default, which allows
such sources to operate in a chroot(2) jail without the associated device
nodes being available.

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/6432)
2018-06-27 07:15:36 +10:00
Andy Polyakov
8d58f0171e rand/rand_unix.c: mask getentropy ELF detection on HP-UX.
Unlike other ELF systems, HP-UX run-time linker fails to detect symbol
availability through weak declaration.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6583)
2018-06-25 16:45:09 +02:00
Dr. Matthias St. Pierre
748eb991f4 RAND_POOL: Add missing implementations for djgpp
Calling the functions rand_pool_add_{additional,nonce}_data()
in crypto/rand/rand_lib.c with no implementation for djgpp/MSDOS
causees unresolved symbols when linking with djgpp.

Reported and fixed by Gisle Vanem

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6421)
2018-06-15 08:13:03 +02:00
Andy Polyakov
913cebc8f4 rand/rand_unix.c: bypass DSO_global_lookup on ELF systems.
If built with no-dso, syscall_random remains "blind" to getentropy.
Since it's possible to detect symbol availability on ELF-based systems
without involving DSO module, bypass it.

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
(Merged from https://github.com/openssl/openssl/pull/6436)
2018-06-09 14:45:05 +02:00
Andy Polyakov
46ceca3c91 rand/rand_unix.c: omit error from DSO_global_lookup.
If built with no-dso, DSO_global_lookup leaves "unsupported" message
in error queue. Since there is a fall-back code, it's unnecessary
distraction.

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
(Merged from https://github.com/openssl/openssl/pull/6436)
2018-06-09 14:43:33 +02:00
Kurt Roeckx
1e653d0ff7 Fix checking the return value of getentropy()
Reviewed-by: Andy Polyakov <appro@openssl.org>
GH: #6405
2018-06-03 12:14:32 +02:00
Kurt Roeckx
2545f9446e Remove support for calling getrandom(), we now always call getentropy()
Only Linux and FreeBSD provide getrandom(), but they both also provide
getentropy() since the same version and we already tried to call that.

Reviewed-by: Andy Polyakov <appro@openssl.org>
GH: #6405
2018-06-03 12:14:26 +02:00
Kurt Roeckx
cf0891b8f1 Look up availability of getentropy() at runtime.
This will actually support most OSs, and at least adds support for
Solaris and OSX

Fixes: #6403
Reviewed-by: Andy Polyakov <appro@openssl.org>
GH: #6405
2018-06-03 12:14:20 +02:00
Kurt Roeckx
8f57662771 Add support for KERN_ARND to get random bytes on NetBSD
Reviewed-by: Andy Polyakov <appro@openssl.org>
GH: #6405
2018-06-03 12:14:12 +02:00
Matt Caswell
83cf7abf8e Update copyright year
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6371)
2018-05-29 13:16:04 +01:00
Kurt Roeckx
3cb7c5cfef Use void in all function definitions that do not take any arguments
Reviewed-by: Rich Salz <rsalz@openssl.org>
GH: #6208
2018-05-11 14:37:48 +02:00
Richard Levitte
06e0950d20 VMS rand: assign before check, not the other way around
items->ile3$w_code was checked before it was assigned its value...

Reviewed-by: Tim Hudson <tjh@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6200)
2018-05-08 20:56:32 +02:00
Richard Levitte
463e6ef500 VMS: modernise rand_pool_acquire_entropy, step 2
Add more items that could serve as entropy source.

Reviewed-by: Andy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6151)
2018-05-03 15:13:15 +02:00
Richard Levitte
ce147f7333 VMS: modernise rand_pool_acquire_entropy, step 1
Stop redefining structures that are already defined in system
headers.  This also means we can stop setting the pointer size
globally, because the system structures will have the correct pointer
sizes either way.  The only exception is passing the right pointer
size to a function.

Stop trying to twist things around with rand(), that's the job of the
DRBG that we feed.

Stop assuming the location of the JPI$_FINALEXC item, look it up
instead.

Signal an exception if the sys$getjpiw call fails (it means the item
list isn't set up right, so works as an assertion, but using VMS
methodology).

Reviewed-by: Andy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6151)
2018-05-03 15:13:15 +02:00
FdaSilvaYY
c7e10755fa opensslconf.h inclusion cleanup
No need to buildtest on opensslconf.h

Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6149)
2018-05-02 23:42:21 +02:00
Richard Levitte
6ebb49f3f9 Change rand_pool_bytes_needed to handle less entropy than 1 per 8 bits
rand_pool_bytes_needed() was constructed in such a way that the
smallest acceptable entropy factor was 1 entropy bits per 8 bits of
data.  At the same time, we have a DRBG_MINMAX_FACTOR that allows
weaker source, as small as 1 bit of entropy per 128 bits of data.
The conclusion is that rand_pool_bytes_needed() needs to change to
support weaker entropy sources.  We therefore change the input of
entropy per byte to be an entropy factor instead.  This entropy factor
expresses how many bits of data it takes (on average) to get 1 bit of
entropy.

Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/6150)
2018-05-02 10:18:29 +02:00