CHANGES

 OpenSSL CHANGES
 _______________

 This is a high-level summary of the most important changes.
 For a full list of changes, see the git commit log; for example,
 https://github.com/openssl/openssl/commits/ and pick the appropriate
 release branch.

 Changes between 1.1.0i and 1.1.1 [xx XXX xxxx]

  *) s390x assembly pack: add (improved) hardware-support for the following
     cryptographic primitives: sha3, shake, aes-gcm, aes-ccm, aes-ctr, aes-ofb,
     aes-cfb/cfb8, aes-ecb.
     [Patrick Steuer]

  *) Make EVP_PKEY_asn1_new() a bit stricter about its input.  A NULL pem_str
     parameter is no longer accepted, as it leads to a corrupt table.  NULL
     pem_str is reserved for alias entries only.
     [Richard Levitte]

  *) Use the new ec_scalar_mul_ladder scaffold to implement a specialized ladder
     step for prime curves. The new implementation is based on formulae from
     differential addition-and-doubling in homogeneous projective coordinates
     from Izu-Takagi "A fast parallel elliptic curve multiplication resistant
     against side channel attacks" and Brier-Joye "Weierstrass Elliptic Curves
     and Side-Channel Attacks" Eq. (8) for y-coordinate recovery, modified
     to work in projective coordinates.
     [Billy Bob Brumley, Nicola Tuveri]

  *) Change generating and checking of primes so that the error rate of not
     being prime depends on the intended use based on the size of the input.
     For larger primes this will result in more rounds of Miller-Rabin.
     The maximal error rate for primes with more than 1080 bits is lowered
     to 2^-128.
     [Kurt Roeckx, Annie Yousar]

  *) Increase the number of Miller-Rabin rounds for DSA key generating to 64.
     [Kurt Roeckx]

  *) The 'tsget' script is renamed to 'tsget.pl', to avoid confusion when
     moving between systems, and to avoid confusion when a Windows build is
     done with mingw vs with MSVC.  For POSIX installs, there's still a
     symlink or copy named 'tsget' to avoid that confusion as well.
     [Richard Levitte]

  *) Revert blinding in ECDSA sign and instead make problematic addition
     length-invariant. Switch even to fixed-length Montgomery multiplication.
     [Andy Polyakov]

  *) Use the new ec_scalar_mul_ladder scaffold to implement a specialized ladder
     step for binary curves. The new implementation is based on formulae from
     differential addition-and-doubling in mixed Lopez-Dahab projective
     coordinates, modified to independently blind the operands.
     [Billy Bob Brumley, Sohaib ul Hassan, Nicola Tuveri]

  *) Add a scaffold to optionally enhance the Montgomery ladder implementation
     for `ec_scalar_mul_ladder` (formerly `ec_mul_consttime`) allowing
     EC_METHODs to implement their own specialized "ladder step", to take
     advantage of more favorable coordinate systems or more efficient
     differential addition-and-doubling algorithms.
     [Billy Bob Brumley, Sohaib ul Hassan, Nicola Tuveri]

  *) Modified the random device based seed sources to keep the relevant
     file descriptors open rather than reopening them on each access.
     This allows such sources to operate in a chroot() jail without
     the associated device nodes being available. This behaviour can be
     controlled using RAND_keep_random_devices_open().
     [Paul Dale]

  *) Numerous side-channel attack mitigations have been applied. This may have
     performance impacts for some algorithms for the benefit of improved
     security. Specific changes are noted in this change log by their respective
     authors.
     [Matt Caswell]

  *) AIX shared library support overhaul. Switch to AIX "natural" way of
     handling shared libraries, which means collecting shared objects of
     different versions and bitnesses in one common archive. This allows to
     mitigate conflict between 1.0 and 1.1 side-by-side installations. It
     doesn't affect the way 3rd party applications are linked, only how
     multi-version installation is managed.
     [Andy Polyakov]

  *) Make ec_group_do_inverse_ord() more robust and available to other
     EC cryptosystems, so that irrespective of BN_FLG_CONSTTIME, SCA
     mitigations are applied to the fallback BN_mod_inverse().
     When using this function rather than BN_mod_inverse() directly, new
     EC cryptosystem implementations are then safer-by-default.
     [Billy Bob Brumley]

  *) Add coordinate blinding for EC_POINT and implement projective
     coordinate blinding for generic prime curves as a countermeasure to
     chosen point SCA attacks.
     [Sohaib ul Hassan, Nicola Tuveri, Billy Bob Brumley]

  *) Add blinding to ECDSA and DSA signatures to protect against side channel
     attacks discovered by Keegan Ryan (NCC Group).
     [Matt Caswell]

  *) Enforce checking in the pkeyutl command line app to ensure that the input
     length does not exceed the maximum supported digest length when performing
     a sign, verify or verifyrecover operation.
     [Matt Caswell]

  *) SSL_MODE_AUTO_RETRY is enabled by default. Applications that use blocking
     I/O in combination with something like select() or poll() will hang. This
     can be turned off again using SSL_CTX_clear_mode().
     Many applications do not properly handle non-application data records, and
     TLS 1.3 sends more of such records. Setting SSL_MODE_AUTO_RETRY works
     around the problems in those applications, but can also break some.
     It's recommended to read the manpages about SSL_read(), SSL_write(),
     SSL_get_error(), SSL_shutdown(), SSL_CTX_set_mode() and
     SSL_CTX_set_read_ahead() again.
     [Kurt Roeckx]

  *) When unlocking a pass phrase protected PEM file or PKCS#8 container, we
     now allow empty (zero character) pass phrases.
     [Richard Levitte]

  *) Apply blinding to binary field modular inversion and remove patent
     pending (OPENSSL_SUN_GF2M_DIV) BN_GF2m_mod_div implementation.
     [Billy Bob Brumley]

  *) Deprecate ec2_mult.c and unify scalar multiplication code paths for
     binary and prime elliptic curves.
     [Billy Bob Brumley]

  *) Remove ECDSA nonce padding: EC_POINT_mul is now responsible for
     constant time fixed point multiplication.
     [Billy Bob Brumley]

  *) Revise elliptic curve scalar multiplication with timing attack
     defenses: ec_wNAF_mul redirects to a constant time implementation
     when computing fixed point and variable point multiplication (which
     in OpenSSL are mostly used with secret scalars in keygen, sign,
     ECDH derive operations).
     [Billy Bob Brumley, Nicola Tuveri, Cesar Pereida García,
      Sohaib ul Hassan]

  *) Updated CONTRIBUTING
     [Rich Salz]

  *) Updated DRBG / RAND to request nonce and additional low entropy
     randomness from the system.
     [Matthias St. Pierre]

  *) Updated 'openssl rehash' to use OpenSSL consistent default.
     [Richard Levitte]

  *) Moved the load of the ssl_conf module to libcrypto, which helps
     loading engines that libssl uses before libssl is initialised.
     [Matt Caswell]

  *) Added EVP_PKEY_sign() and EVP_PKEY_verify() for EdDSA
     [Matt Caswell]

  *) Fixed X509_NAME_ENTRY_set to get multi-valued RDNs right in all cases.
     [Ingo Schwarze, Rich Salz]

  *) Added output of accepting IP address and port for 'openssl s_server'
     [Richard Levitte]

  *) Added a new API for TLSv1.3 ciphersuites:
        SSL_CTX_set_ciphersuites()
        SSL_set_ciphersuites()
     [Matt Caswell]

  *) Memory allocation failures consistenly add an error to the error
     stack.
     [Rich Salz]

  *) Don't use OPENSSL_ENGINES and OPENSSL_CONF environment values
     in libcrypto when run as setuid/setgid.
     [Bernd Edlinger]

  *) Load any config file by default when libssl is used.
     [Matt Caswell]

  *) Added new public header file <openssl/rand_drbg.h> and documentation
     for the RAND_DRBG API. See manual page RAND_DRBG(7) for an overview.
     [Matthias St. Pierre]

  *) QNX support removed (cannot find contributors to get their approval
     for the license change).
     [Rich Salz]

  *) TLSv1.3 replay protection for early data has been implemented. See the
     SSL_read_early_data() man page for further details.
     [Matt Caswell]

  *) Separated TLSv1.3 ciphersuite configuration out from TLSv1.2 ciphersuite
     configuration. TLSv1.3 ciphersuites are not compatible with TLSv1.2 and
     below. Similarly TLSv1.2 ciphersuites are not compatible with TLSv1.3.
     In order to avoid issues where legacy TLSv1.2 ciphersuite configuration
     would otherwise inadvertently disable all TLSv1.3 ciphersuites the
     configuration has been separated out. See the ciphers man page or the
     SSL_CTX_set_ciphersuites() man page for more information.
     [Matt Caswell]