Log Message:
nettle: updated to 3.6

Nettle 3.6:

This release adds a couple of new features, most notable being
support for ED448 signatures.

It is not binary compatible with earlier releases. The shared
library names are libnettle.so.8.0 and libhogweed.so.6.0, with
sonames nibnettle.so.8 and libhogweed.so.6. The changed
sonames are mainly to avoid upgrade problems with recent
GnuTLS versions, that depend on Nettle internals outside of
the advertised ABI. But also because of the removal of
internal poly1305 functions which were undocumented but
declared in an installed header file, see Interface changes
below.

New features:

* Support for Curve448 and ED448 signatures. Contributed by
  Daiki Ueno.

* Support for SHAKE256 (SHA3 variant with arbitrary output
  size). Contributed by Daiki Ueno.

* Support for SIV-CMAC (Synthetic Initialization Vector) mode,
  contributed by Nikos Mavrogiannopoulos.

* Support for CMAC64, contributed by Dmitry Baryshkov.

* Support for the "CryptoPro" variant of the GOST hash
  function, as gosthash94cp. Contributed by Dmitry Baryshkov.

* Support for GOST DSA signatures, including GOST curves
  gc256b and gc512a. Contributed by Dmitry Baryshkov.

* Support for Intel CET in x86 and x86_64 assembly files, if
  enabled via CFLAGS (gcc --fcf-protection=full). Contributed
  by H.J. Lu and Simo Sorce.

* A few new functions to improve support for the Chacha
  variant with 96-bit nonce and 32-bit block counter (the
  existing functions use nonce and counter of 64-bit each),
  and functions to set the counter. Contributed by Daiki Ueno.

* New interface, struct nettle_mac, for MAC (message
  authentication code) algorithms. This abstraction is only
  for MACs that don't require a per-message nonce. For HMAC,
  the key size is fixed, and equal the digest size of the
  underlying hash function.

Bug fixes:

* Fix bug in cfb8_decrypt. Previously, the IV was not updated
  correctly in the case of input data shorter than the block
  size. Reported by Stephan Mueller, fixed by Daiki Ueno.

* Fix configure check for __builtin_bswap64, the incorrect
  check would result in link errors on platforms missing this
  function. Patch contributed by George Koehler.

* All use of old-fashioned suffix rules in the Makefiles have
  been replaced with %-pattern rules. Nettle's use of suffix
  rules in earlier versions depended on undocumented GNU make
  behavior, which is being deprecated in GNU make 4.3.

  Building with other make programs than GNU make is untested
  and unsupported. (Building with BSD make or Solaris make
  used to work years ago, but has not been tested recently).

Interface changes:

* Declarations of internal poly1305.h functions have been
  removed from the header file poly1305.h, to make it clear
  that they are not part of the advertised API or ABI.

Miscellaneous:

* Building the public key support of nettle now requires GMP
  version 6.1.0 or later (unless --enable-mini-gmp is used).

* A fair amount of changes to ECC internals, with a few
  deleted and a few new fields in the internal struct
  ecc_curve. Files and functions have been renamed to more
  consistently match the curve name, e.g., ecc-256.c has been
  renamed to ecc-secp256r1.c.

* Documentation for chacha-poly1305 updated. It is no longer
  experimental. The implementation was updated to follow RFC
  8439 in Nettle-3.1, but that was not documented or announced
  at the time.