for specialized Montgomery ladder implementations

PR #6009 and #6070 replaced the default EC point multiplication path for
prime and binary curves with a unified Montgomery ladder implementation
with various timing attack defenses (for the common paths when a secret
scalar is feed to the point multiplication).
The newly introduced default implementation directly used
EC_POINT_add/dbl in the main loop.

The scaffolding introduced by this commit allows EC_METHODs to define a
specialized `ladder_step` function to improve performances by taking
advantage of efficient formulas for differential addition-and-doubling
and different coordinate systems.

- `ladder_pre` is executed before the main loop of the ladder: by
  default it copies the input point P into S, and doubles it into R.
  Specialized implementations could, e.g., use this hook to transition
  to different coordinate systems before copying and doubling;
- `ladder_step` is the core of the Montgomery ladder loop: by default it
  computes `S := R+S; R := 2R;`, but specific implementations could,
  e.g., implement a more efficient formula for differential
  addition-and-doubling;
- `ladder_post` is executed after the Montgomery ladder loop: by default
  it's a noop, but specialized implementations could, e.g., use this
  hook to transition back from the coordinate system used for optimizing
  the differential addition-and-doubling or recover the y coordinate of
  the result point.

This commit also renames `ec_mul_consttime` to `ec_scalar_mul_ladder`,
as it better corresponds to what this function does: nothing can be
truly said about the constant-timeness of the overall execution of this
function, given that the underlying operations are not necessarily
constant-time themselves.
What this implementation ensures is that the same fixed sequence of
operations is executed for each scalar multiplication (for a given
EC_GROUP), with no dependency on the value of the input scalar.
Co-authored-by: NSohaib ul Hassan <soh.19.hassan@gmail.com>
Co-authored-by: NBilly Brumley <bbrumley@gmail.com>
Reviewed-by: NAndy Polyakov <appro@openssl.org>
Reviewed-by: NMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6690)

Run `make update ERROR_REBUILD=-rebuild` to remove some stale error
codes for SM2 (which is now using its own submodule for error codes,
i.e., `SM2_*`).
Reviewed-by: NAndy Polyakov <appro@openssl.org>
Reviewed-by: NMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6690)

Move base 2^64 code to own #if section. It was nested in base 2^51 section,
which arguably might have been tricky to follow.
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6699)

Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6699)

Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6699)

Base 2^64 addition/subtraction and final reduction failed to treat
partially reduced values correctly.

Thanks to Wycheproof Project for vectors and Paul Kehrer for report.
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6699)

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

Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5254)

"Computationally constant-time" means that it might still leak
information about input's length, but only in cases when input
is missing complete BN_ULONG limbs. But even then leak is possible
only if attacker can observe memory access pattern with limb
granularity.
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5254)

Test that we never negotiate TLSv1.3 using GOST
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6650)

Check that we are either configured for PSK, or that we have a TLSv1.3
capable certificate type. DSA certs can't be used in TLSv1.3 and we
don't (currently) allow GOST ones either (owing to the lack of standard
sig algs).
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6650)

Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6650)

Fixes #6513
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6650)

Change the description for BN_hex2bn() so that it uses the same BIGNUM argument name as its prototype.

CLA: trivial
Reviewed-by: NMatthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: NRichard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6712)

Reviewed-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NAndy Polyakov <appro@openssl.org>

Note that exported functions maintain original behaviour, so that
external callers won't observe difference. While internally we can
now perform Montogomery multiplication on fixed-length vectors, fixed
at modulus size. The new functions, bn_to_mont_fixed_top and
bn_mul_mont_fixed_top, are declared in bn_int.h, because one can use
them even outside bn, e.g. in RSA, DSA, ECDSA...
Reviewed-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NDavid Benjamin <davidben@google.com>
(Merged from https://github.com/openssl/openssl/pull/6662)

The new flag marks vectors that were not treated with bn_correct_top,
in other words such vectors are permitted to be zero padded. For now
it's BN_DEBUG-only flag, as initial use case for zero-padded vectors
would be controlled Montgomery multiplication/exponentiation, not
general purpose. For general purpose use another type might be more
appropriate. Advantage of this suggestion is that it's possible to
back-port it...

bn/bn_div.c: fix memory sanitizer problem.
bn/bn_sqr.c: harmonize with BN_mul.
Reviewed-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NDavid Benjamin <davidben@google.com>
(Merged from https://github.com/openssl/openssl/pull/6662)

Reviewed-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NDavid Benjamin <davidben@google.com>
(Merged from https://github.com/openssl/openssl/pull/6662)

Reviewed-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NDavid Benjamin <davidben@google.com>
(Merged from https://github.com/openssl/openssl/pull/6662)

Trouble is that addition is postponing expansion till carry is
calculated, and if addition carries, top word can be zero, which
triggers assertion in bn_check_top.
Reviewed-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NDavid Benjamin <davidben@google.com>
(Merged from https://github.com/openssl/openssl/pull/6662)

Signed-off-by: NPatrick Steuer <patrick.steuer@de.ibm.com>
Reviewed-by: NTim Hudson <tjh@openssl.org>
Reviewed-by: NRichard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5246)

To avoid the possibility that someone creates rem.exe, rem.bat or
rem.cmd, simply don't use it.  In the cases it was used, it was to
avoid empty lines, but it turns out that nmake handles those fine, so
no harm done.
Reviewed-by: NAndy Polyakov <appro@openssl.org>
Reviewed-by: NBernd Edlinger <bernd.edlinger@hotmail.de>
(Merged from https://github.com/openssl/openssl/pull/6686)

It seems that nmake first tries to run executables on its own, and
only pass commands to cmd if that fails.  That means it's possible to
have nmake run something like 'echo.exe' when the builtin 'echo'
command was expected, which might give us unexpected results.

To get around this, we create our own echoing script and call it
explicitly from the nmake makefile.

Fixes #6670
Reviewed-by: NAndy Polyakov <appro@openssl.org>
Reviewed-by: NBernd Edlinger <bernd.edlinger@hotmail.de>
(Merged from https://github.com/openssl/openssl/pull/6686)

Fix the NULL check lack in a different way that is more compatible with
non-NULL branch.  Refer #6632

Also mark and pop the error stack instead of clearing all errors when something
goes awry in CONF_get_number.
Reviewed-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NAndy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6643)

Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6689)

The reason is that we override Text::Template::append_text_to_output(),
and it didn't exist before Text::Template 1.46.

Fixes #6641
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6682)

Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6682)

This enables us to require module versions, and to fall back to a
bundled version if the system version is too low.
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6682)

We need to check that __GNUC__ is defined before trying to use it.
This demands a slightly different way to define DECLARE_DEPRECATED.
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6680)

Reviewed-by: NPaul Dale <paul.dale@oracle.com>
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6676)

Also fixed a memory leak found by the test.
Reviewed-by: NAndy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6681)

[extended tests]
Reviewed-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NRichard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6661)

Address even Coverity nit.
Reviewed-by: NPaul Dale <paul.dale@oracle.com>
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6671)

The sense of the check for build-time support for most hashes was inverted.

CLA: trivial
Reviewed-by: NRichard Levitte <levitte@openssl.org>
Reviewed-by: NPaul Dale <paul.dale@oracle.com>
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6673)

Reviewed-by: NRichard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6669)

CLA: trivial
Reviewed-by: NAndy Polyakov <appro@openssl.org>
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6667)

OpenSSL 1.1.0 supports the use of this environment variable for
passing to the build files.  For the sake of backward compatibility,
we keep it.
Reviewed-by: NTim Hudson <tjh@openssl.org>
Reviewed-by: NPaul Dale <paul.dale@oracle.com>
Reviewed-by: NBernd Edlinger <bernd.edlinger@hotmail.de>
(Merged from https://github.com/openssl/openssl/pull/6668)

Reviewed-by: NPaul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/6602)

Reviewed-by: NTim Hudson <tjh@openssl.org>
Reviewed-by: NMatthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
GH: #6666

Also avoids calling EVP_MD_size() and a missing negative result check.

Issue found by Coverity.
Reviewed-by: NAndy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6592)