Running make_errors.go every time a function is renamed is incredibly
tedious. Plus we keep getting them wrong.

Instead, sample __func__ (__FUNCTION__ in MSVC) in the OPENSSL_PUT_ERROR macro
and store it alongside file and line number. This doesn't change the format of
ERR_print_errors, however ERR_error_string_n now uses the placeholder
"OPENSSL_internal" rather than an actual function name since that only takes
the uint32_t packed error code as input.

This updates err scripts to not emit the function string table. The
OPENSSL_PUT_ERROR invocations, for now, still include the extra
parameter. That will be removed in a follow-up.

BUG=468039

Change-Id: Iaa2ef56991fb58892fa8a1283b3b8b995fbb308d
Reviewed-on: https://boringssl-review.googlesource.com/5275
Reviewed-by: Adam Langley <agl@google.com>

RSA and ECDSA will both require being able to convert ASN.1 INTEGERs to
and from DER. Don't bother handling negative BIGNUMs for now. It doesn't
seem necessary and saves bothering with two's-complement vs
sign-and-magnitude.

BUG=499653

Change-Id: I1e80052067ed528809493af73b04f82539d564ff
Reviewed-on: https://boringssl-review.googlesource.com/5268
Reviewed-by: Adam Langley <agl@google.com>

The functions BN_rshift and BN_lshift shift their arguments to the right or
left by a specified number of bits. Unpredicatable results (including
crashes) can occur if a negative number is supplied for the shift value.

Thanks to Mateusz Kocielski (LogicalTrust), Marek Kroemeke and Filip Palian
for discovering and reporting this issue.

(Imported from upstream's 7cc18d8158b5fc2676393d99b51c30c135502107.)

Change-Id: Ib9f5e410a46df3d7f02a61374807fba209612bd3
Reviewed-on: https://boringssl-review.googlesource.com/4892
Reviewed-by: Adam Langley <agl@google.com>

This saves about 6-7k of error data.

Change-Id: Ic28593d4a1f5454f00fb2399d281c351ee57fb14
Reviewed-on: https://boringssl-review.googlesource.com/3385
Reviewed-by: Adam Langley <agl@google.com>

Previously, error strings were kept in arrays for each subdirectory and
err.c would iterate over them all and insert them at init time to a hash
table.

This means that, even if you have a shared library and lots of processes
using that, each process has ~30KB of private memory from building that
hash table.

This this change, all the error strings are built into a sorted list and
are thus static data. This means that processes can share the error
information and it actually saves binary space because of all the
pointer overhead in the old scheme. Also it saves the time taken
building the hash table at startup.

This removes support for externally-supplied error string data.

Change-Id: Ifca04f335c673a048e1a3e76ff2b69c7264635be