Reviewed-by: NAndy Polyakov <appro@openssl.org>
Reviewed-by: NRichard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2924)

- Reject fractional seconds
- Reject offsets
- Check that the date/time digits are in valid range.
- Add documentation for X509_cmp_time

GH issue 2620
Reviewed-by: NRichard Levitte <levitte@openssl.org>
Reviewed-by: NRich Salz <rsalz@openssl.org>

Previous commits fixed the implementation of the %e and %g format
specifiers as well as other issues. This commit adds a test.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

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

test_ecdh and test_ecdsa are made to depend on no-ec being false.
test_hmac is made not to depend on algorithm at all.

Based on a contribution by Alessandro Ghedini <alessandro@ghedini.me>
Reviewed-by: NRich Salz <rsalz@openssl.org>

Very simple test recipes easily become tedious, so they might benefit
from being made as simple as possible.  Therefore, OpenSSL::Test::Simple
is born.  It currently provides but one function, simple_test(), which
takes a minimum of two parameters (test name and program to run), with
the optional third, being the algorithm to be checked for before
running the test itself.

All recipes with that simple thing to do have been rewritten to be as
minimal as possible.
Reviewed-by: NRich Salz <rsalz@openssl.org>

These recipes all correspond to a compiled test program.
Reviewed-by: NRich Salz <rsalz@openssl.org>

The math recipes are among the heavier, but also quite important.
For the BN test, we have previously relied on bc to verify the numbers.
Unfortunately, bc doesn't exist everywhere, making tests on some platforms
rather painful.  With the new recipe (recipes/10-test_bn.t), we rely
on perl's Math::BigInt and a homegrown simple calculator (recipes/bc.pl)
that can do enough to cover for bc.
Reviewed-by: NRich Salz <rsalz@openssl.org>