DH: add some basic tests (and comments)

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6273)

DH: add simple getters for commonly used DH struct members

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6273)

Make BN_GF2m_mod_arr more constant time

Experiments have shown that the lookup table used by BN_GF2m_mod_arr
introduces sufficient timing signal to recover the private key for an
attacker with access to cache timing information on the victim's host.
This only affects binary curves (which are less frequently used).

No CVE is considered necessary for this issue.

The fix is to replace the lookup table with an on-the-fly calculation of
the value from the table instead, which can be performed in constant time.

Thanks to Youngjoo Shin for reporting this issue.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6270)

Improve testing of tickets with post-handshake auth

Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5227)

Add documentation for the ability to control the number of tickets

Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5227)

Change the default number of NewSessionTickets we send to 2

Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5227)

Allow configuation of the number of TLSv1.3 session tickets via SSL_CONF

Also allows the apps to set it.

Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5227)

Enable the ability to set the number of TLSv1.3 session tickets sent

We send a session ticket automatically in TLSv1.3 at the end of the
handshake. This commit provides the ability to set how many tickets should
be sent. By default this is one.

Fixes #4978

Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5227)

Add a note on CHANGES and NEWS in CONTRIBUTING

Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/6249)

When producing man-pages, ensure NAME section is one line only

There are *roff parsers that are strict about the NAME section being
one line only.  The man(7) on Debian GNU/Linux suggests that this is
appropriate, so we compensate our multi-line NAME sections by fixing
the *roff output.

Noted by Eric S. Raymond

Related to #6264

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6268)

NOTES.ANDROID: fix typo in build notes

CLA: trivial

Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6244)

windows-makefile.tmpl: delete export library prior link.

LINK can outsmart itself and choose to not update export .lib upon
corresponding .dll re-link. Since dependency is between .lib and all
.obj-s, re-compilation of any .obj makes NMAKE relink .dll and all
.exe-s over and over...

Reviewed-by: Rich Salz <rsalz@openssl.org>

Suport TLSv1.3 draft 28

Also retains support for drafts 27 and 26

Fixes #6257

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6258)

Fix no-tls1_2

Also fixes no-tls1_2-method, no-tls1_3, no-tls, no-ec

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6253)

Fix no-psk

Fixes #6239

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6253)

CI config: no need to make both install and install_docs

'install' depends on 'install_docs', so making the latter explicit is
a waste.

Reviewed-by: Andy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6250)

Link in passphrase-encoding(7) in relevant documentation

Reviewed-by: Andy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6179)

Docs: add general document on how pass phrases are handled

Reviewed-by: Andy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6179)

UI console: Restore tty settings, do not force ECHO after prompt

The Console UI method always set echo on after prompting without
echo.  However, echo might not have been on originally, so just
restore the original TTY settings.

Fixes #2373

Reviewed-by: Andy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6156)

apps/speed: Add brainpool curves support

Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6133)

apps/speed: fix possible OOB access in some EC arrays

because there are actually 18 curves defined, but only 16 are plugged for
ecdsa test.
Deduce array size using OSSL_NELEM and so remove various magic numbers,
which required some declarations moving.
Implement OPT_PAIR list search without a null-ending element.
Fix some comparison between signed and unsigned integer expressions.

Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6133)

Set sess to NULL after freeing it.

Found by OSS-fuzz

Bug introduced in commit 61fb59238dad6452a37ec14513fae617a4faef29

Reviewed-by: Matt Caswell <matt@openssl.org>
GH: #6235

Don't memcpy the contents of an empty fragment

In DTLS if we have buffered a fragment for a zero length message (e.g.
ServerHelloDone) then, when we unbuffered the fragment, we were attempting
to memcpy the contents of the fragment which is zero length and a NULL
pointer. This is undefined behaviour. We should check first whether we
have a zero length fragment.

Fixes a travis issue.

[extended tests]

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6223)

In cases where we ask PEM_def_callback for minimum 0 length, accept 0 length

Fixes #4716

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6173)

Fix typo: 'is an error occurred' in documentation

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6229)

Rework the decrypt ticket callback

Don't call the decrypt ticket callback if we've already encountered a
fatal error. Do call it if we have an empty ticket present.

Change the return code to have 5 distinct returns codes and separate it
from the input status value.

Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6198)

Fix mem leak in sslapi test

The recent change in behaviour where you do not get a NewSessionTicket
message sent if you established the connection using a PSK caused a mem
leak to be triggered in sslapitest. It was actually a latent bug and we
were just lucky we never hit it before. The problem is due to complexity
with the way PSK sessions were set up in the early_data tests. PSK session
reference counting was handled differently to normal session reference
counting. This meant there were lots of special cases in the code where
we don't free a session if it is a PSK. It makes things easier if we just
handle PSK reference counts in the same way as other session reference
counts, and then we can remove all of the special case code.

Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6198)

Add a test for the ticket callbacks

Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6198)

Document when a new session ticket gets created on resumption

Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6198)

Fix ticket callbacks in TLSv1.3

The return value from the ticket_key callback was not properly handled in
TLSv1.3, so that a ticket was *always* renewed even if the callback
requested that it should not be.

Also the ticket decrypt callback was not being called at all in TLSv1.3.

Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6198)

Flush server side unauthenticated writes

When a server call SSL_write_early_data() to write to an unauthenticated
client the buffering BIO is still in place, so we should ensure we flush
the write.

Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6198)

Add some more SSL_pending() and SSL_has_pending() tests

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6159)

Don't set TCP_NODELAY on a UDP socket

This was preventing DTLS connections from being made from the command line.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6159)

Mark DTLS records as read when we have finished with them

The TLS code marks records as read when its finished using a record. The DTLS code did
not do that. However SSL_has_pending() relies on it. So we should make DTLS consistent.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6159)

Test an old style PSK callback with no cert will prefer SHA-256

If using an old style PSK callback and no certificate is configured for
the server, we should prefer ciphersuites based on SHA-256, because that
is the default hash for those callbacks as specified in the TLSv1.3 spec.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6215)

Provide documentation for the -psk_session option

The s_client/s_server docs were missing documentation for this option.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6215)

Prefer SHA-256 ciphersuites if using old style PSKs

If we have no certificate and we are using "old style" PSKs then we will
always default to using SHA-256 for that PSK. However we may have selected
a ciphersuite that is not based on SHA-256. Therefore if we see that there
are no certificates and we have been configured for "old style" PSKs then
we should prefer SHA-256 based ciphersuites during the selection process.

Fixes #6197

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6215)

Use void in all function definitions that do not take any arguments

Reviewed-by: Rich Salz <rsalz@openssl.org>
GH: #6208

rsaz_avx2_eligible doesn't take parameters

Reviewed-by: Rich Salz <rsalz@openssl.org>
GH: #6208

Set the ossl_shim to auto retry if not running asynchronously

In certain circumstances in the DTLS code we have to drop a record (e.g. if
it is a stale retransmit). We then have to move on to try and read the next
record. Some applications using blocking sockets (e.g. s_server/s_client
will hang if there isn't actually any data to be read from the socket yet).
Others can tolerate this. Therefore SSL_read()/SSL_write() can sometimes
return SSL_ERROR_WANT_READ/SSL_ERROR_WANT_WRITE even when using blocking
sockets. Applications can use the mode SSL_MODE_AUTO_RETRY, to switch this
behaviour off so that we never return unless we have read the data we
wanted to.

Commit ad96225285 fixed a DTLS problem where we always retried even if
SSL_MODE_AUTO_RETRY was not set. However that fix caused the Boring
ossl_shim to fail in some tests because it was relying on the previous
(buggy) behaviour. The ossl_shim should be set into SSL_MODE_AUTO_RETRY if
it is not operating asynchronously to avoid this problem.

[extended tests]

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6216)

PPC assembly pack: add POWER9 results.

Reviewed-by: Rich Salz <rsalz@openssl.org>

.travis.yml: add pair of linux-ppc64le targets.

One is clang --strict-warnings and one gcc sanitizer extended test.
Sanitizer build is quite expensive, can take >30 mins and is commented
for occasions when there is reason to believe that PPC-specific problem
can be diagnosed with sanitizer.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6192)

Fix no-cms

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6205)

Fix no-tls1_2, no-tls1_2-method, no-chacha and no-poly1305

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6205)

Fix typos in x509 documentation

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6207)

Add CHANGES entry for PR#6009

Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6070)

Add blinding in BN_GF2m_mod_inv for binary field inversions

Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6070)

ECC: unify generic ec2 and ecp scalar multiplication, deprecate ec2_mult.c

Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6070)

ECDSA: remove nonce padding (delegated to EC_POINT_mul)

* EC_POINT_mul is now responsible for constant time point multiplication
  (for single fixed or variable point multiplication, when the scalar is
  in the range [0,group_order), so we need to strip the nonce padding
  from ECDSA.
* Entry added to CHANGES
* Updated EC_POINT_mul documentation
  - Integrate existing EC_POINT_mul and EC_POINTs_mul entries in the
    manpage to reflect the shift in constant-time expectations when
    performing a single fixed or variable point multiplication;
  - Add documentation to ec_method_st to reflect the updated "contract"
    between callers and implementations of ec_method_st.mul.

Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6070)

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)

Fix --strict-warnings build of ppc-linux target

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6191)

ec/ec_mult.c: get BN_CTX_start,end sequence right.

Triggered by Coverity analysis.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6190)

Add a DTLS test for dropped records

Drop a record from a handshake and check that we can still complete the
handshake. Repeat for all records in the handshake.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6170)

Keep the DTLS timer running after the end of the handshake if appropriate

During a full handshake the server is the last one to "speak". The timer
should continue to run until we know that the client has received our last
flight (e.g. because we receive some application data).

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6170)

Only auto-retry for DTLS if configured to do so

Otherwise we may end up in a hang when using blocking sockets

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6170)

Fix s_client and s_server so that they correctly handle the DTLS timer

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6170)

Don't fail on an out-of-order CCS in DTLS

Fixes #4929

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6170)

Add a CMS API test

Previous tests only invoked CMS via the command line app. This test uses
the CMS API directly to do and encrypt and decrypt operation. This test
would have caught the memory leak fixed by the previous commit (when
building with enable-crypto-mdebug).

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6142)

Fix a mem leak in CMS

The function CMS_RecipientInfo_set0_pkey() is a "set0" and therefore
memory management passes to OpenSSL. If the same function is called again
then we should ensure that any previous value that was set is freed first
before we set it again.

Fixes #5052

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6142)

windows-makefile.tmpl: rearrange cleanup commands to avoid ...

deletion of *.exp files in krb5 sub-module.

Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6186)

.travis.yml: temporarily mask gcc-5 ubsan build.

Linking fails with "unrecognized option '--push-state--no-as-needed'",
which is beyond our control.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6185)

.travis.yml: minor facelift

Apparently trusty image has newer clang, there is no need to pull
clang-3.9 packages. It's clang-5.0.0, installation is a bit quirky,
as it fails to compile for example strcmp(s,"-") without warning,
and complains about unreferred -I flags. But it's argued that benefits
of exercising newer sanitizer outweights the inconvenience of
additional -D__NO_STRING_INLINE and -Wno-unused-command-line-argument.

Also pull golang when actually needed.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6185)

Cleanup

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6183)

Configure: fix Mac OS X builds that still require makedepend

Earlier Apple Xcode compilers, e.g. one targeting Mac OS X 10.7, don't
support dependency generation and one still has to use makedepend.  It's
unclear when it was fixed, but all clang-based Apple compilers seem to
support -M options.

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Andy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6169)

Configure: pass more suitable argument to compiler_predefined().

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6174)

Configure: move --noexecstack probe to Configure.

config probe doesn't work in cross-compile scenarios or with clang.
In addition consolidate -Qunused-arguments handling.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6174)

BIO_s_mem() write: Skip early when input length is zero

When the input length is zero, just return zero early.  Otherwise,
there's a small chance that memory allocation is engaged, fails and
returns -1, which is a bit confusing when nothing should be written.

Fixes #4782 #4827

Reviewed-by: Ben Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/6175)

docs: Fix typo EVP_PKEY_new_id -> EVP_PKEY_CTX_new_id

Reviewed-by: Tim Hudson <tjh@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6177)

v3_purp.c: add locking to x509v3_cache_extensions()

Fixes #6121

Thanks to Mingtao Yang for reporting this bug.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6162)

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)

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)

Return an error from BN_mod_inverse if n is 1 (or -1)

Calculating BN_mod_inverse where n is 1 (or -1) doesn't make sense. We
should return an error in that case. Instead we were returning a valid
result with value 0.

Fixes #6004

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6119)

Make X509_VERIFY_PARAM_get_hostflags() take a const arg

Commit 5b748dea5 added this function which should have taken a const
argument.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6154)

Add a test for SSL_get_shared_ciphers()

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6113)

Fix a bug in create_ssl_ctx_pair()

The max protocol version was only being set on the server side. It should
have been done on both the client and the server.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6113)

Add some documentation for SSL_get_shared_ciphers()

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6113)

Fix comment in ssl_locl.h

The ciphers field in a session contains the stack of ciphers offered by
the client.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6113)

Fix SSL_get_shared_ciphers()

The function SSL_get_shared_ciphers() is supposed to return ciphers shared
by the client and the server. However it only ever returned the client
ciphers.

Fixes #5317

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6113)

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)

bn/asm/*-mont.pl: harmonize with BN_from_montgomery_word.

Montgomery multiplication post-conditions in some of code paths were
formally non-constant time. Cache access pattern was result-neutral,
but a little bit asymmetric, which might have produced a signal [if
processor reordered load and stores at run-time].

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6141)

apps/speed.c: merge parameters defining EC curves to test ...

... and unify 'bits' declarations and printing format.

Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6132)

a_strex.c: prevent out of bound read in do_buf()

which is used for ASN1_STRING_print_ex*() and X509_NAME_print_ex*().

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6105)

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)

Add a note about Nagle's algorithm on the SSL_connect man page

Fixes #4237

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Ben Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/6143)

Fix memory leaks in CA related functions.

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4700)

Fix regression with session cache use by clients

Commit d316cdcf6d8d6934663278145fe0a8191e14a8c5 introduced some extra
checks into the session-cache update procedure, intended to prevent
the caching of sessions whose resumption would lead to a handshake
failure, since if the server is authenticating the client, there needs to
be an application-set "session id context" to match up to the authentication
context.  While that change is effective for its stated purpose, there
was also some collatoral damage introduced along with the fix -- clients
that set SSL_VERIFY_PEER are not expected to set an sid_ctx, and so
their usage of session caching was erroneously denied.

Fix the scope of the original commit by limiting it to only acting
when the SSL is a server SSL.

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5967)

Improve error handling in rand_init function

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6124)

Add getter for X509_VERIFY_PARAM_get_hostflags

Fixes #5061

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6139)

Clarify BN_mod_exp docs

Specifically this is not supported with an even modulus and
BN_FLG_CONSTTIME.

Fixes #5082

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6137)

Fix some errors and missing info in the CMS docs

Fixes #5063

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6134)

Prepare for 1.1.1-pre7-dev

Reviewed-by: Rich Salz <rsalz@openssl.org>

Prepare for 1.1.1-pre6 release

Reviewed-by: Rich Salz <rsalz@openssl.org>

Update copyright year

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6145)

Use the config file from the source not the host for the tests

Fixes: #6046

Reviewed-by: Rich Salz <rsalz@openssl.org>
GH: #6125

Configurations/unix-Makefile.tmpl: harmonize with no-engine.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6106)

Configurations/10-main.conf: force no-engine on ios targets.

Rationale for enforcing no-engine is because of disconnect between
compile-time config and run-time, which is a per-application sandbox
directory which one can't predict in advance. Besides, none of the
bundled engines actually give an edge on iOS...

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6106)

Don't cleanup uninitialized thread local slots

Fixes: #6120

Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
(Merged from https://github.com/openssl/openssl/pull/6123)

Fix drbg thread cleanup and error handling

Fixes: #6081

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6089)

Update version docs

Make it clear that you should not attempt to get the version before the
first handshake is complete.

Fixes #2893

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6013)

apps/s_server.c: Avoid unused variable due to 'no-dtls'

Fixes #6098

Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/6104)