I left many "#if 0" lines, usually because I thought we would
probably want to revisit them later, or because they provided
some useful internal documentation tips.
Reviewed-by: NAndy Polyakov <appro@openssl.org>

The mkstack.pl script now generates the entire safestack.h file.
It generates output that follows the coding style.
Also, removed all instances of the obsolete IMPLEMENT_STACK_OF
macro.
Reviewed-by: NAndy Polyakov <appro@openssl.org>

A few minor cleanups to remove pre-processor "#if 1" stuff.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

Document SSL_get_extms_support().

Modify behaviour of SSL_get_extms_support() so it returns -1 if the
master secret support of the peer is not known (e.g. handshake in progress).
Reviewed-by: NTim Hudson <tjh@openssl.org>
Reviewed-by: NMatt Caswell <matt@openssl.org>

Reviewed-by: NTim Hudson <tjh@openssl.org>
Reviewed-by: NMatt Caswell <matt@openssl.org>

Retrieve handshake hashes in a separate function. This tidies the existing
code and will be used for extended master secret generation.
Reviewed-by: NTim Hudson <tjh@openssl.org>
Reviewed-by: NMatt Caswell <matt@openssl.org>

An expired IETF Internet-Draft (seven years old) that nobody
implements, and probably just as good as NSA DRBG work.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

Remove OPENSSL_NO_BUF_FREELISTS. This was turned on by default,
so the work here is removing the 'maintain our own freelist' code.
Also removed a minor old Windows-multibyte/widechar conversion flag.
Reviewed-by: NAndy Polyakov <appro@openssl.org>

Reviewed-by: NTim Hudson <tjh@openssl.org>

Reviewed-by: NTim Hudson <tjh@openssl.org>

Sometimes it fails to format them very well, and sometimes it corrupts them!
This commit moves some particularly problematic ones.
Reviewed-by: NTim Hudson <tjh@openssl.org>

This last one for this ticket.  Removes WIN16.
So long, MS_CALLBACK and MS_FAR.  We won't miss you.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

context was also inherited (matches that of the existing SSL_CTX).
Reviewed-by: NTim Hudson <tjh@openssl.org>

Reviewed-by: NTim Hudson <tjh@openssl.org>

when its SSL_CTX is updated.

From BoringSSL commit
https://boringssl.googlesource.com/boringssl/+/a5dc545bbcffd9c24cebe65e9ab5ce72d4535e3aReviewed-by: NRich Salz <rsalz@openssl.org>

RT3638
Reviewed-by: NEmilia Käsper <emilia@openssl.org>

Reviewed-by: NTim Hudson <tjh@openssl.org>

Reviewed-by: NEmilia Käsper <emilia@openssl.org>

Reviewed-by: NRichard Levitte <levitte@openssl.org>

FIPS_mode() exists in all versions of OpenSSL but always returns 0 if OpenSSL is not FIPS
capable.
Reviewed-by: NTim Hudson <tjh@openssl.org>

The only support for SSLv2 left is receiving a SSLv2 compatible client hello.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

and instead use the value provided by the underlying BIO. Also provide some
new DTLS_CTRLs so that the library user can set the mtu without needing to
know this constant. These new DTLS_CTRLs provide the capability to set the
link level mtu to be used (i.e. including this IP/UDP overhead). The previous
DTLS_CTRLs required the library user to subtract this overhead first.
Reviewed-by: NTim Hudson <tjh@openssl.org>

SSL_set_SSL_CTX is used to change the SSL_CTX for SNI, keep the
supported signature algorithms and raw cipherlist.
Reviewed-by: NTim Hudson <tjh@openssl.org>

listed after TLS_FALLBACK_SCSV.

RT: 3575
Reviewed-by: NEmilia Kasper <emilia@openssl.org>

Reviewed-by: NStephen Henson <steve@openssl.org>

Use the same structure for client and server custom extensions.

Add utility functions in new file t1_ext.c.
Use new utility functions to handle custom server and client extensions
and remove a lot of code duplication.
Reviewed-by: NEmilia Käsper <emilia@openssl.org>

Move custom extension structures from SSL_CTX to CERT structure.

This change means the form can be revised in future without binary
compatibility issues. Also since CERT is part of SSL structures
so per-SSL custom extensions could be supported in future as well as
per SSL_CTX.
Reviewed-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NEmilia Käsper <emilia@openssl.org>

Remove RFC5878 code. It is no longer needed for CT and has numerous bugs

PR: 3317

Security callback: selects which parameters are permitted including
sensible defaults based on bits of security.

The "parameters" which can be selected include: ciphersuites,
curves, key sizes, certificate signature algorithms, supported
signature algorithms, DH parameters, SSL/TLS version, session tickets
and compression.

In some cases prohibiting the use of a parameters will mean they are
not advertised to the peer: for example cipher suites and ECC curves.
In other cases it will abort the handshake: e.g DH parameters or the
peer key size.

Documentation to follow...

New function ssl_cipher_disabled.

Check for disabled client ciphers using ssl_cipher_disabled.

New function to return only supported ciphers.

New option to ciphers utility to print only supported ciphers.

Add auto DH parameter support. This is roughly equivalent to the
ECDH auto curve selection but for DH. An application can just call

SSL_CTX_set_auto_dh(ctx, 1);

and appropriate DH parameters will be used based on the size of the
server key.

Unlike ECDH there is no way a peer can indicate the range of DH parameters
it supports. Some peers cannot handle DH keys larger that 1024 bits for
example. In this case if you call:

SSL_CTX_set_auto_dh(ctx, 2);

Only 1024 bit DH parameters will be used.

If the server key is 7680 bits or more in size then 8192 bit DH parameters
will be used: these will be *very* slow.

The old export ciphersuites aren't supported but those are very
insecure anyway.

Partial fix for PR#3183.

DHE is the standard term used by the RFCs and by other TLS
implementations.  It's useful to have the internal variables use the
standard terminology.

This patch leaves a synonym SSL_kEDH in place, though, so that older
code can still be built against it, since that has been the
traditional API.  SSL_kEDH should probably be deprecated at some
point, though.

ECDHE is the standard term used by the RFCs and by other TLS
implementations.  It's useful to have the internal variables use the
standard terminology.

This patch leaves a synonym SSL_kEECDH in place, though, so that older
code can still be built against it, since that has been the
traditional API.  SSL_kEECDH should probably be deprecated at some
point, though.

New functions to retrieve internal pointers to X509_VERIFY_PARAM
for SSL_CTX and SSL structures.
(cherry picked from commit be0c9270690ed9c1799900643cab91de146de857)

New functions to retrieve current certificate or private key
from an SSL_CTX.

Constify SSL_get_private_key().

PR#3106