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 1.1.1f and 1.1.1g [21 Apr 2020]

  *) Fixed segmentation fault in SSL_check_chain()
     Server or client applications that call the SSL_check_chain() function
     during or after a TLS 1.3 handshake may crash due to a NULL pointer
     dereference as a result of incorrect handling of the
     "signature_algorithms_cert" TLS extension. The crash occurs if an invalid
     or unrecognised signature algorithm is received from the peer. This could
     be exploited by a malicious peer in a Denial of Service attack.
     (CVE-2020-1967)
     [Benjamin Kaduk]

  *) Added AES consttime code for no-asm configurations
     an optional constant time support for AES was added
     when building openssl for no-asm.
     Enable with: ./config no-asm -DOPENSSL_AES_CONST_TIME
     Disable with: ./config no-asm -DOPENSSL_NO_AES_CONST_TIME
     At this time this feature is by default disabled.
     It will be enabled by default in 3.0.
     [Bernd Edlinger]

 Changes between 1.1.1e and 1.1.1f [31 Mar 2020]

  *) Revert the change of EOF detection while reading in libssl to avoid
     regressions in applications depending on the current way of reporting
     the EOF. As the existing method is not fully accurate the change to
     reporting the EOF via SSL_ERROR_SSL is kept on the current development
     branch and will be present in the 3.0 release.
     [Tomas Mraz]

  *) Revised BN_generate_prime_ex to not avoid factors 3..17863 in p-1
     when primes for RSA keys are computed.
     Since we previously always generated primes == 2 (mod 3) for RSA keys,
     the 2-prime and 3-prime RSA modules were easy to distinguish, since
     N = p*q = 1 (mod 3), but N = p*q*r = 2 (mod 3). Therefore fingerprinting
     2-prime vs. 3-prime RSA keys was possible by computing N mod 3.
     This avoids possible fingerprinting of newly generated RSA modules.
     [Bernd Edlinger]

 Changes between 1.1.1d and 1.1.1e [17 Mar 2020]
  *) Properly detect EOF while reading in libssl. Previously if we hit an EOF
     while reading in libssl then we would report an error back to the
     application (SSL_ERROR_SYSCALL) but errno would be 0. We now add
     an error to the stack (which means we instead return SSL_ERROR_SSL) and
     therefore give a hint as to what went wrong.
     [Matt Caswell]

  *) Check that ed25519 and ed448 are allowed by the security level. Previously
     signature algorithms not using an MD were not being checked that they were
     allowed by the security level.
     [Kurt Roeckx]

  *) Fixed SSL_get_servername() behaviour. The behaviour of SSL_get_servername()
     was not quite right. The behaviour was not consistent between resumption
     and normal handshakes, and also not quite consistent with historical
     behaviour. The behaviour in various scenarios has been clarified and
     it has been updated to make it match historical behaviour as closely as
     possible.
     [Matt Caswell]

  *) [VMS only] The header files that the VMS compilers include automatically,
     __DECC_INCLUDE_PROLOGUE.H and __DECC_INCLUDE_EPILOGUE.H, use pragmas that
     the C++ compiler doesn't understand.  This is a shortcoming in the
     compiler, but can be worked around with __cplusplus guards.

     C++ applications that use OpenSSL libraries must be compiled using the
     qualifier '/NAMES=(AS_IS,SHORTENED)' to be able to use all the OpenSSL
     functions.  Otherwise, only functions with symbols of less than 31
     characters can be used, as the linker will not be able to successfully
     resolve symbols with longer names.
     [Richard Levitte]

  *) Corrected the documentation of the return values from the EVP_DigestSign*
     set of functions.  The documentation mentioned negative values for some
     errors, but this was never the case, so the mention of negative values
     was removed.

     Code that followed the documentation and thereby check with something
     like 'EVP_DigestSignInit(...) <= 0' will continue to work undisturbed.
     [Richard Levitte]

  *) Fixed an an overflow bug in the x64_64 Montgomery squaring procedure
     used in exponentiation with 512-bit moduli. No EC algorithms are
     affected. Analysis suggests that attacks against 2-prime RSA1024,
     3-prime RSA1536, and DSA1024 as a result of this defect would be very
     difficult to perform and are not believed likely. Attacks against DH512
     are considered just feasible. However, for an attack the target would
     have to re-use the DH512 private key, which is not recommended anyway.
     Also applications directly using the low level API BN_mod_exp may be
     affected if they use BN_FLG_CONSTTIME.
     (CVE-2019-1551)
     [Andy Polyakov]

  *) Added a new method to gather entropy on VMS, based on SYS$GET_ENTROPY.
     The presence of this system service is determined at run-time.
     [Richard Levitte]

  *) Added newline escaping functionality to a filename when using openssl dgst.
     This output format is to replicate the output format found in the '*sum'
     checksum programs. This aims to preserve backward compatibility.
     [Matt Eaton, Richard Levitte, and Paul Dale]

  *) Print all values for a PKCS#12 attribute with 'openssl pkcs12', not just
     the first value.
     [Jon Spillett]

 Changes between 1.1.1c and 1.1.1d [10 Sep 2019]

  *) Fixed a fork protection issue. OpenSSL 1.1.1 introduced a rewritten random
     number generator (RNG). This was intended to include protection in the
     event of a fork() system call in order to ensure that the parent and child
     processes did not share the same RNG state. However this protection was not
     being used in the default case.

     A partial mitigation for this issue is that the output from a high
     precision timer is mixed into the RNG state so the likelihood of a parent
     and child process sharing state is significantly reduced.

     If an application already calls OPENSSL_init_crypto() explicitly using
     OPENSSL_INIT_ATFORK then this problem does not occur at all.
     (CVE-2019-1549)
     [Matthias St. Pierre]

  *) For built-in EC curves, ensure an EC_GROUP built from the curve name is
     used even when parsing explicit parameters, when loading a serialized key
     or calling `EC_GROUP_new_from_ecpkparameters()`/
     `EC_GROUP_new_from_ecparameters()`.
     This prevents bypass of security hardening and performance gains,
     especially for curves with specialized EC_METHODs.
     By default, if a key encoded with explicit parameters is loaded and later
     serialized, the output is still encoded with explicit parameters, even if
     internally a "named" EC_GROUP is used for computation.
     [Nicola Tuveri]

  *) Compute ECC cofactors if not provided during EC_GROUP construction. Before
     this change, EC_GROUP_set_generator would accept order and/or cofactor as
     NULL. After this change, only the cofactor parameter can be NULL. It also
     does some minimal sanity checks on the passed order.
     (CVE-2019-1547)
     [Billy Bob Brumley]

  *) Fixed a padding oracle in PKCS7_dataDecode and CMS_decrypt_set1_pkey.
     An attack is simple, if the first CMS_recipientInfo is valid but the
     second CMS_recipientInfo is chosen ciphertext. If the second
     recipientInfo decodes to PKCS #1 v1.5 form plaintext, the correct
     encryption key will be replaced by garbage, and the message cannot be
     decoded, but if the RSA decryption fails, the correct encryption key is
     used and the recipient will not notice the attack.
     As a work around for this potential attack the length of the decrypted
     key must be equal to the cipher default key length, in case the
     certifiate is not given and all recipientInfo are tried out.
     The old behaviour can be re-enabled in the CMS code by setting the
     CMS_DEBUG_DECRYPT flag.
     (CVE-2019-1563)
     [Bernd Edlinger]

  *) Early start up entropy quality from the DEVRANDOM seed source has been
     improved for older Linux systems.  The RAND subsystem will wait for
     /dev/random to be producing output before seeding from /dev/urandom.
     The seeded state is stored for future library initialisations using
     a system global shared memory segment.  The shared memory identifier
     can be configured by defining OPENSSL_RAND_SEED_DEVRANDOM_SHM_ID to
     the desired value.  The default identifier is 114.
     [Paul Dale]

  *) Correct the extended master secret constant on EBCDIC systems. Without this
     fix TLS connections between an EBCDIC system and a non-EBCDIC system that
     negotiate EMS will fail. Unfortunately this also means that TLS connections
     between EBCDIC systems with this fix, and EBCDIC systems without this
     fix will fail if they negotiate EMS.
     [Matt Caswell]

  *) Use Windows installation paths in the mingw builds

     Mingw isn't a POSIX environment per se, which means that Windows
     paths should be used for installation.
     (CVE-2019-1552)
     [Richard Levitte]

  *) Changed DH_check to accept parameters with order q and 2q subgroups.
     With order 2q subgroups the bit 0 of the private key is not secret
     but DH_generate_key works around that by clearing bit 0 of the
     private key for those. This avoids leaking bit 0 of the private key.
     [Bernd Edlinger]

  *) Significantly reduce secure memory usage by the randomness pools.
     [Paul Dale]

  *) Revert the DEVRANDOM_WAIT feature for Linux systems

     The DEVRANDOM_WAIT feature added a select() call to wait for the
     /dev/random device to become readable before reading from the
     /dev/urandom device.

     It turned out that this change had negative side effects on
     performance which were not acceptable. After some discussion it
     was decided to revert this feature and leave it up to the OS
     resp. the platform maintainer to ensure a proper initialization
     during early boot time.
     [Matthias St. Pierre]

 Changes between 1.1.1b and 1.1.1c [28 May 2019]

  *) Add build tests for C++.  These are generated files that only do one
     thing, to include one public OpenSSL head file each.  This tests that
     the public header files can be usefully included in a C++ application.

     This test isn't enabled by default.  It can be enabled with the option
     'enable-buildtest-c++'.
     [Richard Levitte]

  *) Enable SHA3 pre-hashing for ECDSA and DSA.
     [Patrick Steuer]

  *) Change the default RSA, DSA and DH size to 2048 bit instead of 1024.
     This changes the size when using the genpkey app when no size is given. It
     fixes an omission in earlier changes that changed all RSA, DSA and DH
     generation apps to use 2048 bits by default.
     [Kurt Roeckx]

  *) Reorganize the manual pages to consistently have RETURN VALUES,
     EXAMPLES, SEE ALSO and HISTORY come in that order, and adjust
     util/fix-doc-nits accordingly.
     [Paul Yang, Joshua Lock]

  *) Add the missing accessor EVP_PKEY_get0_engine()
     [Matt Caswell]

  *) Have apps like 's_client' and 's_server' output the signature scheme
     along with other cipher suite parameters when debugging.
     [Lorinczy Zsigmond]

  *) Make OPENSSL_config() error agnostic again.
     [Richard Levitte]

  *) Do the error handling in RSA decryption constant time.
     [Bernd Edlinger]

  *) Prevent over long nonces in ChaCha20-Poly1305.

     ChaCha20-Poly1305 is an AEAD cipher, and requires a unique nonce input
     for every encryption operation. RFC 7539 specifies that the nonce value
     (IV) should be 96 bits (12 bytes). OpenSSL allows a variable nonce length
     and front pads the nonce with 0 bytes if it is less than 12
     bytes. However it also incorrectly allows a nonce to be set of up to 16
     bytes. In this case only the last 12 bytes are significant and any
     additional leading bytes are ignored.

     It is a requirement of using this cipher that nonce values are
     unique. Messages encrypted using a reused nonce value are susceptible to
     serious confidentiality and integrity attacks. If an application changes
     the default nonce length to be longer than 12 bytes and then makes a
     change to the leading bytes of the nonce expecting the new value to be a
     new unique nonce then such an application could inadvertently encrypt
     messages with a reused nonce.

     Additionally the ignored bytes in a long nonce are not covered by the
     integrity guarantee of this cipher. Any application that relies on the
     integrity of these ignored leading bytes of a long nonce may be further
     affected. Any OpenSSL internal use of this cipher, including in SSL/TLS,
     is safe because no such use sets such a long nonce value. However user
     applications that use this cipher directly and set a non-default nonce
     length to be longer than 12 bytes may be vulnerable.

     This issue was reported to OpenSSL on 16th of March 2019 by Joran Dirk
     Greef of Ronomon.
     (CVE-2019-1543)
     [Matt Caswell]

  *) Add DEVRANDOM_WAIT feature for Linux systems

     On older Linux systems where the getrandom() system call is not available,
     OpenSSL normally uses the /dev/urandom device for seeding its CSPRNG.
     Contrary to getrandom(), the /dev/urandom device will not block during
     early boot when the kernel CSPRNG has not been seeded yet.

     To mitigate this known weakness, use select() to wait for /dev/random to
     become readable before reading from /dev/urandom.

  *) Ensure that SM2 only uses SM3 as digest algorithm
     [Paul Yang]

 Changes between 1.1.1a and 1.1.1b [26 Feb 2019]

  *) Added SCA hardening for modular field inversion in EC_GROUP through
     a new dedicated field_inv() pointer in EC_METHOD.
     This also addresses a leakage affecting conversions from projective
     to affine coordinates.
     [Billy Bob Brumley, Nicola Tuveri]

  *) Change the info callback signals for the start and end of a post-handshake
     message exchange in TLSv1.3. In 1.1.1/1.1.1a we used SSL_CB_HANDSHAKE_START
     and SSL_CB_HANDSHAKE_DONE. Experience has shown that many applications get
     confused by this and assume that a TLSv1.2 renegotiation has started. This
     can break KeyUpdate handling. Instead we no longer signal the start and end
     of a post handshake message exchange (although the messages themselves are
     still signalled). This could break some applications that were expecting
     the old signals. However without this KeyUpdate is not usable for many
     applications.
     [Matt Caswell]

  *) Fix a bug in the computation of the endpoint-pair shared secret used
     by DTLS over SCTP. This breaks interoperability with older versions
     of OpenSSL like OpenSSL 1.1.0 and OpenSSL 1.0.2. There is a runtime
     switch SSL_MODE_DTLS_SCTP_LABEL_LENGTH_BUG (off by default) enabling
     interoperability with such broken implementations. However, enabling
     this switch breaks interoperability with correct implementations.

  *) Fix a use after free bug in d2i_X509_PUBKEY when overwriting a
     re-used X509_PUBKEY object if the second PUBKEY is malformed.
     [Bernd Edlinger]

  *) Move strictness check from EVP_PKEY_asn1_new() to EVP_PKEY_asn1_add0().
     [Richard Levitte]

  *) Remove the 'dist' target and add a tarball building script.  The
     'dist' target has fallen out of use, and it shouldn't be
     necessary to configure just to create a source distribution.
     [Richard Levitte]

 Changes between 1.1.1 and 1.1.1a [20 Nov 2018]

  *) Timing vulnerability in DSA signature generation

     The OpenSSL DSA signature algorithm has been shown to be vulnerable to a
     timing side channel attack. An attacker could use variations in the signing
     algorithm to recover the private key.

     This issue was reported to OpenSSL on 16th October 2018 by Samuel Weiser.
     (CVE-2018-0734)
     [Paul Dale]

  *) Timing vulnerability in ECDSA signature generation

     The OpenSSL ECDSA signature algorithm has been shown to be vulnerable to a
     timing side channel attack. An attacker could use variations in the signing
     algorithm to recover the private key.

     This issue was reported to OpenSSL on 25th October 2018 by Samuel Weiser.
     (CVE-2018-0735)
     [Paul Dale]

  *) Added EVP_PKEY_ECDH_KDF_X9_63 and ecdh_KDF_X9_63() as replacements for
     the EVP_PKEY_ECDH_KDF_X9_62 KDF type and ECDH_KDF_X9_62(). The old names
     are retained for backwards compatibility.
     [Antoine Salon]

  *) Fixed the issue that RAND_add()/RAND_seed() silently discards random input
     if its length exceeds 4096 bytes. The limit has been raised to a buffer size
     of two gigabytes and the error handling improved.

     This issue was reported to OpenSSL by Dr. Falko Strenzke. It has been
     categorized as a normal bug, not a security issue, because the DRBG reseeds
     automatically and is fully functional even without additional randomness
     provided by the application.

 Changes between 1.1.0i and 1.1.1 [11 Sep 2018]

  *) Add a new ClientHello callback. Provides a callback interface that gives
     the application the ability to adjust the nascent SSL object at the
     earliest stage of ClientHello processing, immediately after extensions have
     been collected but before they have been processed. In particular, this
     callback can adjust the supported TLS versions in response to the contents
     of the ClientHello
     [Benjamin Kaduk]

  *) Add SM2 base algorithm support.
     [Jack Lloyd]

  *) 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 consistently 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]

  *) On POSIX (BSD, Linux, ...) systems the ocsp(1) command running
     in responder mode now supports the new "-multi" option, which
     spawns the specified number of child processes to handle OCSP
     requests.  The "-timeout" option now also limits the OCSP
     responder's patience to wait to receive the full client request
     on a newly accepted connection. Child processes are respawned
     as needed, and the CA index file is automatically reloaded
     when changed.  This makes it possible to run the "ocsp" responder
     as a long-running service, making the OpenSSL CA somewhat more
     feature-complete.  In this mode, most diagnostic messages logged
     after entering the event loop are logged via syslog(3) rather than
     written to stderr.
     [Viktor Dukhovni]

  *) Added support for X448 and Ed448. Heavily based on original work by
     Mike Hamburg.
     [Matt Caswell]

  *) Extend OSSL_STORE with capabilities to search and to narrow the set of
     objects loaded.  This adds the functions OSSL_STORE_expect() and
     OSSL_STORE_find() as well as needed tools to construct searches and
     get the search data out of them.
     [Richard Levitte]

  *) Support for TLSv1.3 added. Note that users upgrading from an earlier
     version of OpenSSL should review their configuration settings to ensure
     that they are still appropriate for TLSv1.3. For further information see:
     https://wiki.openssl.org/index.php/TLS1.3
     [Matt Caswell]

  *) Grand redesign of the OpenSSL random generator

     The default RAND method now utilizes an AES-CTR DRBG according to
     NIST standard SP 800-90Ar1. The new random generator is essentially
     a port of the default random generator from the OpenSSL FIPS 2.0
     object module. It is a hybrid deterministic random bit generator
     using an AES-CTR bit stream and which seeds and reseeds itself
     automatically using trusted system entropy sources.

     Some of its new features are:
      o Support for multiple DRBG instances with seed chaining.
      o The default RAND method makes use of a DRBG.
      o There is a public and private DRBG instance.
      o The DRBG instances are fork-safe.
      o Keep all global DRBG instances on the secure heap if it is enabled.
      o The public and private DRBG instance are per thread for lock free
        operation
     [Paul Dale, Benjamin Kaduk, Kurt Roeckx, Rich Salz, Matthias St. Pierre]

  *) Changed Configure so it only says what it does and doesn't dump
     so much data.  Instead, ./configdata.pm should be used as a script
     to display all sorts of configuration data.
     [Richard Levitte]

  *) Added processing of "make variables" to Configure.
     [Richard Levitte]

  *) Added SHA512/224 and SHA512/256 algorithm support.
     [Paul Dale]

  *) The last traces of Netware support, first removed in 1.1.0, have
     now been removed.
     [Rich Salz]

  *) Get rid of Makefile.shared, and in the process, make the processing
     of certain files (rc.obj, or the .def/.map/.opt files produced from
     the ordinal files) more visible and hopefully easier to trace and
     debug (or make silent).
     [Richard Levitte]

  *) Make it possible to have environment variable assignments as
     arguments to config / Configure.
     [Richard Levitte]

  *) Add multi-prime RSA (RFC 8017) support.
     [Paul Yang]

  *) Add SM3 implemented according to GB/T 32905-2016
     [ Jack Lloyd <jack.lloyd@ribose.com>,
       Ronald Tse <ronald.tse@ribose.com>,
       Erick Borsboom <erick.borsboom@ribose.com> ]

  *) Add 'Maximum Fragment Length' TLS extension negotiation and support
     as documented in RFC6066.
     Based on a patch from Tomasz Moń
     [Filipe Raimundo da Silva]

  *) Add SM4 implemented according to GB/T 32907-2016.
     [ Jack Lloyd <jack.lloyd@ribose.com>,
       Ronald Tse <ronald.tse@ribose.com>,
       Erick Borsboom <erick.borsboom@ribose.com> ]

  *) Reimplement -newreq-nodes and ERR_error_string_n; the
     original author does not agree with the license change.
     [Rich Salz]

  *) Add ARIA AEAD TLS support.
     [Jon Spillett]

  *) Some macro definitions to support VS6 have been removed.  Visual
     Studio 6 has not worked since 1.1.0
     [Rich Salz]

  *) Add ERR_clear_last_mark(), to allow callers to clear the last mark
     without clearing the errors.
     [Richard Levitte]

  *) Add "atfork" functions.  If building on a system that without
     pthreads, see doc/man3/OPENSSL_fork_prepare.pod for application
     requirements.  The RAND facility now uses/requires this.
     [Rich Salz]

  *) Add SHA3.
     [Andy Polyakov]

  *) The UI API becomes a permanent and integral part of libcrypto, i.e.
     not possible to disable entirely.  However, it's still possible to
     disable the console reading UI method, UI_OpenSSL() (use UI_null()
     as a fallback).

     To disable, configure with 'no-ui-console'.  'no-ui' is still
     possible to use as an alias.  Check at compile time with the
     macro OPENSSL_NO_UI_CONSOLE.  The macro OPENSSL_NO_UI is still
     possible to check and is an alias for OPENSSL_NO_UI_CONSOLE.
     [Richard Levitte]

  *) Add a STORE module, which implements a uniform and URI based reader of
     stores that can contain keys, certificates, CRLs and numerous other
     objects.  The main API is loosely based on a few stdio functions,
     and includes OSSL_STORE_open, OSSL_STORE_load, OSSL_STORE_eof,
     OSSL_STORE_error and OSSL_STORE_close.
     The implementation uses backends called "loaders" to implement arbitrary
     URI schemes.  There is one built in "loader" for the 'file' scheme.
     [Richard Levitte]

  *) Add devcrypto engine.  This has been implemented against cryptodev-linux,
     then adjusted to work on FreeBSD 8.4 as well.
     Enable by configuring with 'enable-devcryptoeng'.  This is done by default
     on BSD implementations, as cryptodev.h is assumed to exist on all of them.
     [Richard Levitte]

  *) Module names can prefixed with OSSL_ or OPENSSL_.  This affects
     util/mkerr.pl, which is adapted to allow those prefixes, leading to
     error code calls like this:

         OSSL_FOOerr(OSSL_FOO_F_SOMETHING, OSSL_FOO_R_WHATEVER);

     With this change, we claim the namespaces OSSL and OPENSSL in a manner
     that can be encoded in C.  For the foreseeable future, this will only
     affect new modules.
     [Richard Levitte and Tim Hudson]

  *) Removed BSD cryptodev engine.
     [Rich Salz]

  *) Add a build target 'build_all_generated', to build all generated files
     and only that.  This can be used to prepare everything that requires
     things like perl for a system that lacks perl and then move everything
     to that system and do the rest of the build there.
     [Richard Levitte]

  *) In the UI interface, make it possible to duplicate the user data.  This
     can be used by engines that need to retain the data for a longer time
     than just the call where this user data is passed.
     [Richard Levitte]

  *) Ignore the '-named_curve auto' value for compatibility of applications
     with OpenSSL 1.0.2.
     [Tomas Mraz <tmraz@fedoraproject.org>]

  *) Fragmented SSL/TLS alerts are no longer accepted. An alert message is 2
     bytes long. In theory it is permissible in SSLv3 - TLSv1.2 to fragment such
     alerts across multiple records (some of which could be empty). In practice
     it make no sense to send an empty alert record, or to fragment one. TLSv1.3
     prohibits this altogether and other libraries (BoringSSL, NSS) do not
     support this at all. Supporting it adds significant complexity to the
     record layer, and its removal is unlikely to cause interoperability
     issues.
     [Matt Caswell]

  *) Add the ASN.1 types INT32, UINT32, INT64, UINT64 and variants prefixed
     with Z.  These are meant to replace LONG and ZLONG and to be size safe.
     The use of LONG and ZLONG is discouraged and scheduled for deprecation
     in OpenSSL 1.2.0.
     [Richard Levitte]

  *) Add the 'z' and 'j' modifiers to BIO_printf() et al formatting string,
     'z' is to be used for [s]size_t, and 'j' - with [u]int64_t.
     [Richard Levitte, Andy Polyakov]

  *) Add EC_KEY_get0_engine(), which does for EC_KEY what RSA_get0_engine()
     does for RSA, etc.
     [Richard Levitte]

  *) Have 'config' recognise 64-bit mingw and choose 'mingw64' as the target
     platform rather than 'mingw'.
     [Richard Levitte]

  *) The functions X509_STORE_add_cert and X509_STORE_add_crl return
     success if they are asked to add an object which already exists
     in the store. This change cascades to other functions which load
     certificates and CRLs.
     [Paul Dale]

  *) x86_64 assembly pack: annotate code with DWARF CFI directives to
     facilitate stack unwinding even from assembly subroutines.
     [Andy Polyakov]

  *) Remove VAX C specific definitions of OPENSSL_EXPORT, OPENSSL_EXTERN.
     Also remove OPENSSL_GLOBAL entirely, as it became a no-op.
     [Richard Levitte]

  *) Remove the VMS-specific reimplementation of gmtime from crypto/o_times.c.
     VMS C's RTL has a fully up to date gmtime() and gmtime_r() since V7.1,
     which is the minimum version we support.
     [Richard Levitte]

  *) Certificate time validation (X509_cmp_time) enforces stricter
     compliance with RFC 5280. Fractional seconds and timezone offsets
     are no longer allowed.
     [Emilia Käsper]

  *) Add support for ARIA
     [Paul Dale]

  *) s_client will now send the Server Name Indication (SNI) extension by
     default unless the new "-noservername" option is used. The server name is
     based on the host provided to the "-connect" option unless overridden by
     using "-servername".
     [Matt Caswell]

  *) Add support for SipHash
     [Todd Short]

  *) OpenSSL now fails if it receives an unrecognised record type in TLS1.0
     or TLS1.1. Previously this only happened in SSLv3 and TLS1.2. This is to
     prevent issues where no progress is being made and the peer continually
     sends unrecognised record types, using up resources processing them.
     [Matt Caswell]

  *) 'openssl passwd' can now produce SHA256 and SHA512 based output,
     using the algorithm defined in
     https://www.akkadia.org/drepper/SHA-crypt.txt
     [Richard Levitte]

  *) Heartbeat support has been removed; the ABI is changed for now.
     [Richard Levitte, Rich Salz]

  *) Support for SSL_OP_NO_ENCRYPT_THEN_MAC in SSL_CONF_cmd.
     [Emilia Käsper]

  *) The RSA "null" method, which was partially supported to avoid patent
     issues, has been replaced to always returns NULL.
     [Rich Salz]


 Changes between 1.1.0h and 1.1.0i [xx XXX xxxx]

  *) Client DoS due to large DH parameter

     During key agreement in a TLS handshake using a DH(E) based ciphersuite a
     malicious server can send a very large prime value to the client. This will
     cause the client to spend an unreasonably long period of time generating a
     key for this prime resulting in a hang until the client has finished. This
     could be exploited in a Denial Of Service attack.

     This issue was reported to OpenSSL on 5th June 2018 by Guido Vranken
     (CVE-2018-0732)
     [Guido Vranken]

  *) Cache timing vulnerability in RSA Key Generation

     The OpenSSL RSA Key generation algorithm has been shown to be vulnerable to
     a cache timing side channel attack. An attacker with sufficient access to
     mount cache timing attacks during the RSA key generation process could
     recover the private key.

     This issue was reported to OpenSSL on 4th April 2018 by Alejandro Cabrera
     Aldaya, Billy Brumley, Cesar Pereida Garcia and Luis Manuel Alvarez Tapia.
     (CVE-2018-0737)
     [Billy Brumley]

  *) 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]

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

  *) 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]

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

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

  *) Certificate time validation (X509_cmp_time) enforces stricter
     compliance with RFC 5280. Fractional seconds and timezone offsets
     are no longer allowed.
     [Emilia Käsper]

  *) Fixed a text canonicalisation bug in CMS

     Where a CMS detached signature is used with text content the text goes
     through a canonicalisation process first prior to signing or verifying a
     signature. This process strips trailing space at the end of lines, converts
     line terminators to CRLF and removes additional trailing line terminators
     at the end of a file. A bug in the canonicalisation process meant that
     some characters, such as form-feed, were incorrectly treated as whitespace
     and removed. This is contrary to the specification (RFC5485). This fix
     could mean that detached text data signed with an earlier version of
     OpenSSL 1.1.0 may fail to verify using the fixed version, or text data
     signed with a fixed OpenSSL may fail to verify with an earlier version of
     OpenSSL 1.1.0. A workaround is to only verify the canonicalised text data
     and use the "-binary" flag (for the "cms" command line application) or set
     the SMIME_BINARY/PKCS7_BINARY/CMS_BINARY flags (if using CMS_verify()).
     [Matt Caswell]

 Changes between 1.1.0g and 1.1.0h [27 Mar 2018]

  *) Constructed ASN.1 types with a recursive definition could exceed the stack

     Constructed ASN.1 types with a recursive definition (such as can be found
     in PKCS7) could eventually exceed the stack given malicious input with
     excessive recursion. This could result in a Denial Of Service attack. There
     are no such structures used within SSL/TLS that come from untrusted sources
     so this is considered safe.

     This issue was reported to OpenSSL on 4th January 2018 by the OSS-fuzz
     project.
     (CVE-2018-0739)
     [Matt Caswell]

  *) Incorrect CRYPTO_memcmp on HP-UX PA-RISC

     Because of an implementation bug the PA-RISC CRYPTO_memcmp function is
     effectively reduced to only comparing the least significant bit of each
     byte. This allows an attacker to forge messages that would be considered as
     authenticated in an amount of tries lower than that guaranteed by the
     security claims of the scheme. The module can only be compiled by the
     HP-UX assembler, so that only HP-UX PA-RISC targets are affected.

     This issue was reported to OpenSSL on 2nd March 2018 by Peter Waltenberg
     (IBM).
     (CVE-2018-0733)
     [Andy Polyakov]

  *) Add a build target 'build_all_generated', to build all generated files
     and only that.  This can be used to prepare everything that requires
     things like perl for a system that lacks perl and then move everything
     to that system and do the rest of the build there.
     [Richard Levitte]

  *) Backport SSL_OP_NO_RENGOTIATION

     OpenSSL 1.0.2 and below had the ability to disable renegotiation using the
     (undocumented) SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS flag. Due to the opacity
     changes this is no longer possible in 1.1.0. Therefore the new
     SSL_OP_NO_RENEGOTIATION option from 1.1.1-dev has been backported to
     1.1.0 to provide equivalent functionality.

     Note that if an application built against 1.1.0h headers (or above) is run
     using an older version of 1.1.0 (prior to 1.1.0h) then the option will be
     accepted but nothing will happen, i.e. renegotiation will not be prevented.
     [Matt Caswell]

  *) Removed the OS390-Unix config target.  It relied on a script that doesn't
     exist.
     [Rich Salz]

  *) rsaz_1024_mul_avx2 overflow bug on x86_64

     There is an overflow bug in the AVX2 Montgomery multiplication procedure
     used in exponentiation with 1024-bit moduli. No EC algorithms are affected.
     Analysis suggests that attacks against RSA and DSA as a result of this
     defect would be very difficult to perform and are not believed likely.
     Attacks against DH1024 are considered just feasible, because most of the
     work necessary to deduce information about a private key may be performed
     offline. The amount of resources required for such an attack would be
     significant. However, for an attack on TLS to be meaningful, the server
     would have to share the DH1024 private key among multiple clients, which is
     no longer an option since CVE-2016-0701.

     This only affects processors that support the AVX2 but not ADX extensions
     like Intel Haswell (4th generation).

     This issue was reported to OpenSSL by David Benjamin (Google). The issue
     was originally found via the OSS-Fuzz project.
     (CVE-2017-3738)
     [Andy Polyakov]

 Changes between 1.1.0f and 1.1.0g [2 Nov 2017]

  *) bn_sqrx8x_internal carry bug on x86_64

     There is a carry propagating bug in the x86_64 Montgomery squaring
     procedure. No EC algorithms are affected. Analysis suggests that attacks
     against RSA and DSA as a result of this defect would be very difficult to
     perform and are not believed likely. Attacks against DH are considered just
     feasible (although very difficult) because most of the work necessary to
     deduce information about a private key may be performed offline. The amount
     of resources required for such an attack would be very significant and
     likely only accessible to a limited number of attackers. An attacker would
     additionally need online access to an unpatched system using the target
     private key in a scenario with persistent DH parameters and a private
     key that is shared between multiple clients.

     This only affects processors that support the BMI1, BMI2 and ADX extensions
     like Intel Broadwell (5th generation) and later or AMD Ryzen.

     This issue was reported to OpenSSL by the OSS-Fuzz project.
     (CVE-2017-3736)
     [Andy Polyakov]

  *) Malformed X.509 IPAddressFamily could cause OOB read

     If an X.509 certificate has a malformed IPAddressFamily extension,
     OpenSSL could do a one-byte buffer overread. The most likely result
     would be an erroneous display of the certificate in text format.