Upgrade libressl. 1/2

[dragonfly.git] / crypto / libressl / ChangeLog

Because this project is maintained both in the OpenBSD tree using CVS and in
Git, it can be confusing following all of the changes.

Most of the libssl and libcrypto source code is is here in OpenBSD CVS:

        http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/lib/libssl/

Some of the libcrypto and OS-compatibility files for entropy and random number
generation are here:

        http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/lib/libcrypto/

A simplified TLS wrapper library is here:

        http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/lib/libtls/

The LibreSSL Portable project copies these portions of the OpenBSD tree, along
with relevant portions of the C library, to a Git repository. This makes it
easier to follow all of the relevant changes to the upstream project in a
single place:

        https://github.com/libressl-portable/openbsd

The portable bits of the project are largely maintained out-of-tree, and their
history is also available from Git.

        https://github.com/libressl-portable/portable

LibreSSL Portable Release Notes:

3.2.2 - Stable release

        * This is the first stable release with the new TLSv1.3
          implementation enabled by default for both client and server. The
          OpenSSL 1.1 TLSv1.3 API is not yet available and will be provided
          in an upcoming release.

        * New X509 certificate chain validator that correctly handles
          multiple paths through intermediate certificates. Loosely based on
          Go's X509 validator.

        * New name constraints verification implementation which passes the
          bettertls.com certificate validation check suite.

        * Improve the handling of BIO_read()/BIO_write() failures in the
          TLSv1.3 stack.

        * Start replacing the existing TLSv1.2 record layer.

        * Define OPENSSL_NO_SSL_TRACE in opensslfeatures.h.

        * Make SSL_CTX_get_ciphers(NULL) return NULL rather than crash.

        * Send alert on ssl_get_prev_session() failure.

        * Zero out variable on the stack to avoid leaving garbage in the tail
          of short session IDs.

        * Move state initialization from SSL_clear() to ssl3_clear() to ensure
          that it gets correctly reinitialized across a SSL_set_ssl_method()
          call.

        * Avoid an out-of-bounds write in BN_rand().

        * Fix numerous leaks in the UI_dup_* functions. Simplify and tidy up
          the code in ui_lib.c.

        * Correctly track selected ALPN length to avoid a potential segmentation
          fault with SSL_get0_alpn_selected() when alpn_selected is NULL.

        * Include machine/endian.h gost2814789.c in order to pick up the
          __STRICT_ALIGNMENT define.

        * Simplify SSL method lookups.

        * Clean up and simplify SSL_get_ciphers(), SSL_set_session(),
          SSL_set_ssl_method() and several internal functions.

        * Correctly handle ssl_cert_dup() failure in SSL_set_SSL_CTX().

        * Refactor dtls1_new(), dtls1_hm_fragment_new(),
          dtls1_drain_fragments(), dtls1_clear_queues().

        * Copy the session ID directly in ssl_get_prev_session() instead of
          handing it through several functions for copying.

        * Clean up and refactor ssl_get_prev_session(); simplify
          tls_decrypt_ticket() and tls1_process_ticket() exit paths.

        * Avoid memset() before memcpy() in CBS_add_bytes().

        * Rewrite X509_INFO_{new,free}() more idiomatically.

        * Remove unnecessary zeroing after recallocarray() in
          ASN1_BIT_STRING_set_bit().

        * Convert openssl(1) ocsp new option handling.

        * Document SSL_set1_host(3), SSL_set_SSL_CTX(3).

        * Document return value from EC_KEY_get0_public_key(3).

        * Greatly expanded test coverage via the tlsfuzzer test scripts.

        * Expanded test coverage via the bettertls certificate test suite.

        * Test interoperability with the Botan TLS client.

        * Make pthread_mutex static initialisation work on Windows.

        * Get __STRICT_ALIGNMENT from machine/endian.h with portable build.

3.2.1 - Development release

        * Propagate alerts from the read half of the TLSv1.3 record layer to I/O
          functions.

        * Send a record overflow alert for TLSv1.3 messages having overlong
          plaintext or inner plaintext.

        * Send an illegal parameter alert if a client sends an invalid DH key
          share.

        * Document PKCS7_final(3), PKCS7_add_attribute(3).

        * Collapse x509v3 directory into x509.

        * Improve TLSv1.3 client certificate selection to allow EC certificates
          instead of only RSA certificates.

        * Fail on receiving an invalid NID in X509_ATTRIBUTE_create() instead
          of constructing a broken objects that may cause NULL pointer accesses.

        * Add support for additional GOST curves from RFC 7836 and
          draft-deremin-rfc4491-bis.

        * Add OIDs for HMAC using the Streebog hash function.

        * Allow GOST R 34.11-2012 in PBE/PBKDF2/PKCS#5.

        * Enable GOST_SIG_FORMAT_RS_LE when verifying certificate signatures.

        * Handle GOST in ssl_cert_dup().

        * Stop sending GOST R 34.10-94 as a CertificateType.

        * Use IANA allocated GOST ClientCertificateTypes.

        * Add a custom copy handler for AES keywrap to fix a use-after-free.

        * Enforce in the TLSv1.3 server that that ClientHello messages after
          a HelloRetryRequest match the original ClientHello as per RFC 8446
          section 4.1.2

        * Document more PKCS7 attribute functions.

        * Document PKCS7_get_signer_info(3).

        * Document PEM_ASN1_read(3) and PEM_ASN1_read_bio(3).

        * Document PEM_def_callback(3).

        * Document EVP_read_pw_string_min(3).

        * Merge documentation of X509_get0_serialNumber from OpenSSL 1.1.1.

        * Document error handling of X509_PUBKEY_get0(3) and X509_PUBKEY_get(3)

        * Document X509_get0_pubkey_bitstr(3).

        * Fix an off-by-one in the CBC padding removal. From BoringSSL.

        * Enforce restrictions on extensions present in the ClientHello as per
          RFC 8446, section 9.2.

        * Add new CMAC_Init(3) and ChaCha(3) manual pages.

        * Fix SSL_shutdown behavior to match the legacy stack.  The previous
          behavior could cause a hang.

        * Add initial support for openbsd/powerpc64.

        * Make the message type available in the internal TLS extensions API
          functions.

        * Enable TLSv1.3 for the generic TLS_method().

        * Convert openssl(1) s_client option handling.

        * Document openssl(1) certhash.

        * Convert openssl(1) verify option handling.

        * Fix a longstanding bug in PEM_X509_INFO_read_bio(3) that could cause
          use-after-free and double-free issues in calling programs.

        * Document PEM_X509_INFO_read(3) and PEM_X509_INFO_read_bio(3).

        * Handle SSL_MODE_AUTO_RETRY being changed during a TLSv1.3 session.

        * Convert openssl(1) s_server option handling.

        * Add minimal info callback support for TLSv1.3.

        * Refactor, clean up and simplify some SSL3/DTLS1 record writing code.

        * Correctly handle server requests for an OCSP response.

        * Add the P-521 curve to the list of curves supported by default
          in the client.

        * Convert openssl(1) req option handling.

        * Avoid calling freezero with a negative size if a server sends a
          malformed plaintext of all zeroes.

        * Send an unexpected message alert if no valid content type is found
          in a TLSv1.3 record.

3.2.0 - Development release

        * Enable TLS 1.3 server side in addition to client by default.
          With this change TLS 1.3 is handled entirely on the new stack
          and state machine, with fallback to the legacy stack and
          state machine for older versions. Note that the OpenSSL TLS 1.3
          API is not yet visible/available.

        * Improve length checks in the TLS 1.3 record layer and provide
          appropriate alerts for violations of record layer limits.

        * Enforce that SNI hostnames received by the TLS server are correctly
          formed as per RFC 5890 and RFC 6066, responding with illegal parameter
          for a nonconformant host name.

        * Support SSL_MODE_AUTO_RETRY in TLS 1.3 to allow the automatic
          retry of handshake messages.

        * Modify I/O behavior so that SSL_MODE_AUTO_RETRY is the default
          similar to new OpenSSL releases.

        * Modify openssl(1) to clear SSL_MODE_AUTO_RETRY appropriately in
          various commands.

        * Add tlsfuzzer based regression tests.

        * Support sending certificate status requests from the TLS 1.3
          client to request OCSP staples for leaf certificates.

        * Support sending certificate status replies from the TLS 1.3 server
          in order to send OCSP staples for leaf certificates.

        * Send correct alerts when handling failed key share extensions
          on the TLS 1.3 server.

        * Various compatibility fixes for TLS 1.3 to 1.2 fallback for
          switching from the new to legacy stacks.

        * Support TLS 1.3 options in the openssl(1) command.

        * Many alert cleanups in TLS 1.3 to provide expected alerts in failure
          conditions.

        * Modify "openssl x509" to display invalid certificate times as
          invalid, and correctly deal with the failing return case from
          X509_cmp_time so that a certificate with an invalid NotAfter does
          not appear valid.

        * Support sending dummy change_cipher_spec records for TLS 1.3 middlebox
          compatibility.

        * Ensure only PSS signatures are used with RSA in TLS 1.3.

        * Ensure that TLS 1.3 clients advertise exactly the "null" compression
          method in its legacy_compression_methods.

        * Correct use of sockaddr_storage instead of sockaddr in openssl(1)
          s_client, which could lead to using 14 bytes of stack garbage instead
          of an IPv6 address in DTLS mode.

        * Use non-expired certificates first when building a certificate chain.

3.1.4 - Interoperability and bug fixes for the TLSv1.3 client:

        * Improve client certificate selection to allow EC certificates
          instead of only RSA certificates.

        * Do not error out if a TLSv1.3 server requests an OCSP response as
          part of a certificate request.

        * Fix SSL_shutdown behavior to match the legacy stack.  The previous
          behaviour could cause a hang.

        * Fix a memory leak and add a missing error check in the handling of
          the key update message.

        * Fix a memory leak in tls13_record_layer_set_traffic_key.

        * Avoid calling freezero with a negative size if a server sends a
          malformed plaintext of all zeroes.

        * Ensure that only PSS may be used with RSA in TLSv1.3 in order
          to avoid using PKCS1-based signatures.

        * Add the P-521 curve to the list of curves supported by default
          in the client.

3.1.3 - Bug fix

        * libcrypto may fail to build a valid certificate chain due to
          expired untrusted issuer certificates.

3.1.2 - Bug fix

        * A TLS client with peer verification disabled may crash when
          contacting a server that sends an empty certificate list.

3.1.1 - Stable release

        * Improved cipher suite handling to automatically include TLSv1.3
          cipher suites when they are not explicitly referred to in the
          cipher string.

        * Improved handling of TLSv1.3 HelloRetryRequests, simplifying
          state transitions and ensuring that the legacy session identifer
          retains the same value across the handshake.

        * Provided TLSv1.3 cipher suite aliases to match the names used
          in RFC 8446.

        * Improved TLSv1.3 client key share handling to allow the use of
          any groups in our configured NID list.

        * Fixed printing the serialNumber with X509_print_ex() fall back to
          the colon separated hex bytes in case greater than int value.

        * Fix to disallow setting the AES-GCM IV length to zero.

        * Added -groups option to openssl(1) s_server subcommand.

        * Fix to show TLSv1.3 extension types with openssl(1) -tlsextdebug.

        * Improved portable builds to support the use of static MSVC runtimes.

        * Fixed portable builds to avoid exporting a sleep() symbol.

3.1.0 - Development release

        * Completed initial TLS 1.3 implementation with a completely new state
          machine and record layer. TLS 1.3 is now enabled by default for the
          client side, with the server side to be enabled in a future release.
          Note that the OpenSSL TLS 1.3 API is not yet visible/available.

        * Many more code cleanups, fixes, and improvements to memory handling
          and protocol parsing.

        * Added RSA-PSS and RSA-OAEP methods from OpenSSL 1.1.1.

        * Ported Cryptographic Message Syntax (CMS) implementation from OpenSSL
          1.1.1 and enabled by default.

        * Improved compatibility by backporting functionality and documentation
          from OpenSSL 1.1.1.

        * Added many new additional crypto test vectors.

        * Adjusted EVP_chacha20()'s behavior to match OpenSSL's semantics.

        * Default CA bundle location is now configurable in portable builds.

        * Added cms subcommand to openssl(1).

        * Added -addext option to openssl(1) req subcommand.

3.0.2 - Stable release

        * Use a valid curve when constructing an EC_KEY that looks like X25519.
          The recent EC group cofactor change results in stricter validation,
          which causes the EC_GROUP_set_generator() call to fail.
          Issue reported and fix tested by rsadowski@

        * Fixed a padding oracle in PKCS7_dataDecode and CMS_decrypt_set1_pkey.
          (Note that the CMS code is currently disabled)
          Port of Edlinger's Fix for CVE-2019-1563 from OpenSSL 1.1.1 (old license) 

        * Avoid a path traversal bug in s_server on Windows when run with the -WWW
          or -HTTP options, due to incomplete path check logic.
          Issue reported and fix tested by Jobert Abma

3.0.1 - Development release

        * Ported Billy Brumley's fix for CVE-2019-1547 in OpenSSL 1.1.1. If a NULL
          or zero cofactor is passed to EC_GROUP_set_generator(), try to compute
          it using Hasse's bound. This works as long as the cofactor is small
          enough.

        * Fixed a memory leak in error paths for eckey_type2param().

        * Initial work on supporting Cryptographic Message Syntax (CMS) in
          libcrypto (not enabled).

        * Various manual page improvements and additions.

        * Added a CMake check for an existing uninstall target, facilitating
          embedding LibreSSL in larger CMake projects, from Matthew Albrecht.

3.0.0 - Development release

        * Completed the port of RSA_METHOD accessors from the OpenSSL 1.1 API.

        * Documented undescribed options and removed unfunctional options
          description in openssl(1) manual.

        * A plethora of small fixes due to regular oss-fuzz testing.

        * Various side channels in DSA and ECDSA were addressed.  These are some of
          the many issues found in an extensive systematic analysis of bignum usage
          by Samuel Weiser, David Schrammel et al.

        * Enabled openssl(1) speed subcommand on Windows platform.

        * Enabled performance optimizations when building with Visual Studio on Windows.

        * Fixed incorrect carry operation in 512 addition for Streebog.

        * Fixed -modulus option with openssl(1) dsa subcommand.

        * Fixed PVK format output issue with openssl(1) dsa and rsa subcommand.

2.9.2 - Bug fixes

        * Fixed portable builds with older versions of MacOS,
          Android targets < API 21, and Solaris 10

        * Fixed SRTP profile advertisement for DTLS servers.

2.9.1 - Stable release

        * Added support for XChaCha20 and XChaCha20-Poly1305.

        * Added support for AES key wrap constructions via the EVP interface.

        * Partial port of the OpenSSL EC_KEY_METHOD API for use by OpenSSH.

        * Added pbkdf2 key derivation support to openssl(1)

        * Removed SHA224 based handshake signatures from consideration for use in a TLS 1.2 handshake.

        * Changed the default digest type of openssl(1) enc to to sha256.

        * Changed the default digest type of openssl(1) dgst to sha256.

        * Changed the default digest type of openssl(1) x509 -fingerprint to sha256.

        * Changed the default digest type of openssl(1) crl -fingerprint to sha256.

        * Improved Windows, Android, and ARM compatibility, including assembly
          optimizations on Mingw-w64 targets.

2.9.0 - Development release

        * Added the SM4 block cipher from the Chinese standard GB/T 32907-2016.

        * Fixed warnings about clock_gettime on Windows Visual Studio builds.

        * Fixed CMake builds on systems where getpagesize is defined as an
          inline function.

        * CRYPTO_LOCK is now automatically initialized, with the legacy
          callbacks stubbed for compatibility.

        * Added the SM3 hash function from the Chinese standard GB/T 32905-2016.

        * Added more OPENSSL_NO_* macros for compatibility with OpenSSL.

        * Added extensive interoperability tests between LibreSSL and OpenSSL
          1.0 and 1.1.

        * Added additional Wycheproof tests and related bug fixes.

        * Simplified sigalgs option processing and handshake signing algorithm

        * Added the ability to use the RSA PSS algorithm for handshake
          signatures.

        * Added bn_rand_interval() and use it in code needing ranges of random
          bn values.

        * Added functionality to derive early, handshake, and application
          secrets as per RFC8446.

        * Added handshake state machine from RFC8446.

        * Removed some ASN.1 related code from libcrypto that had not been used
          since around 2000.

        * Unexported internal symbols and internalized more record layer structs.

        * Added support for assembly optimizations on 32-bit ARM ELF targets.

        * Improved protection against timing side channels in ECDSA signature
          generation.

        * Coordinate blinding was added to some elliptic curves. This is the
          last bit of the work by Brumley et al. to protect against the
          Portsmash vulnerability.

        * Ensure transcript handshake is always freed with TLS 1.2.

2.8.2 - Stable release

        * Added Wycheproof support for ECDH and ECDSA Web Crypto test vectors,
          along with test harness fixes.

        * Fixed memory leak in nc(1)

2.8.1 - Test and compatibility improvements

        * Added Wycheproof support for ECDH, RSASSA-PSS, AES-GCM,
          AES-CMAC, AES-CCM, AES-CBC-PKCS5, DSA, ChaCha20-Poly1305, ECDSA, and
          X25519 test vectors. Applied appropriate fixes for errors uncovered
          by tests.

        * Simplified key exchange signature generation and verification.

        * Fixed a one-byte buffer overrun in callers of EVP_read_pw_string

        * Converted more code paths to use CBB/CBS. All handshake messages are
          now created by CBB.

        * Fixed various memory leaks found by Coverity.

        * Simplified session ticket parsing and handling, inspired by
          BoringSSL.

        * Modified signature of CRYPTO_mem_leaks_* to return -1. This function
          is a no-op in LibreSSL, so this function returns an error to not
          indicate the (non-)existence of memory leaks.

        * SSL_copy_session_id, PEM_Sign, EVP_EncodeUpdate, BIO_set_cipher,
          X509_OBJECT_up_ref_count now return an int for error handling,
          matching OpenSSL.

        * Converted a number of #defines into proper functions, matching
          OpenSSL's ABI.

        * Added X509_get0_serialNumber from OpenSSL.

        * Removed EVP_PKEY2PKCS8_broken and PKCS8_set_broken, while adding
          PKCS8_pkey_add1_attr_by_NID and PKCS8_pkey_get0_attrs, matching
          OpenSSL.

        * Removed broken pkcs8 formats from openssl(1).

        * Converted more functions in public API to use const arguments.

        * Stopped handing AES-GCM in ssl_cipher_get_evp, since they use the
          EVP_AEAD interface.

        * Stopped using composite EVP_CIPHER AEADs.

        * Added timing-safe compares for checking results of signature
          verification. There are no known attacks, this is just inexpensive
          prudence.

        * Correctly clear the current cipher state, when changing cipher state.
          This fixed an issue where renegotiation of cipher suites would fail
          when switched from AEAD to non-AEAD or vice-versa.
          Issue reported by Bernard Spil.

        * Added more cipher tests to appstest.sh, including all TLSv1.2
          ciphers.

        * Added RSA_meth_get_finish() RSA_meth_set1_name() from OpenSSL.

        * Added new EVP_CIPHER_CTX_(get|set)_iv() API that allows the IV to be
          retrieved and set with appropriate validation.

2.8.0 - Bug fixes, security, and compatibility improvements

        * Extensive documentation updates and additional API history.

        * Fixed a pair of 20+ year-old bugs in X509_NAME_add_entry

        * Tighten up checks for various X509_VERIFY_PARAM functions,
          'poisoning' parameters so that an unverified certificate cannot be
          used if it fails verification.

        * Fixed a potential memory leak on failure in ASN1_item_digest

        * Fixed a potential memory alignment crash in asn1_item_combine_free

        * Removed unused SSL3_FLAGS_DELAY_CLIENT_FINISHED and
          SSL3_FLAGS_POP_BUFFER flags in write path, simplifying IO paths.

        * Removed SSL_OP_TLS_ROLLBACK_BUG buggy client workarounds.

        * Made ENGINE_finish and ENGINE_free succeed on NULL and simplify callers
          and matching OpenSSL behavior, rewrote ENGINE_* documentation.

        * Added const annotations to many existing APIs from OpenSSL, making
          interoperability easier for downstream applications.

        * Fixed small timing side-channels in ecdsa_sign_setup and
          dsa_sign_setup.

        * Documented security pitfalls with BN_FLG_CONSTTIME and constant-time
          operation of BN_* functions.

        * Updated BN_clear to use explicit_bzero.

        * Added a missing bounds check in c2i_ASN1_BIT_STRING.

        * More CBS conversions, including simplifications to RSA key exchange,
          and converted code to use dedicated buffers for secrets.

        * Removed three remaining single DES cipher suites.

        * Fixed a potential leak/incorrect return value in DSA signature
          generation.

        * Added a blinding value when generating DSA and ECDSA signatures, in
          order to reduce the possibility of a side-channel attack leaking the
          private key.

        * Added ECC constant time scalar multiplication support.
          From Billy Brumley and his team at Tampere University of Technology.

        * Revised the implementation of RSASSA-PKCS1-v1_5 to match the
          specification in RFC 8017. Based on an OpenSSL commit by David
          Benjamin.

        * Cleaned up BN_* implementations following changes made in OpenSSL by
          Davide Galassi and others.

2.7.4 - Security fixes

        * Avoid a timing side-channel leak when generating DSA and ECDSA
          signatures. This is caused by an attempt to do fast modular
          arithmetic, which introduces branches that leak information
          regarding secret values. Issue identified and reported by Keegan
          Ryan of NCC Group.

        * Reject excessively large primes in DH key generation. Problem
          reported by Guido Vranken to OpenSSL
          (https://github.com/openssl/openssl/pull/6457) and based on his
          diff.

2.7.3 - Bug fixes

        * Removed incorrect NULL checks in DH_set0_key(). Reported by Ondrej
          Sury

        * Fixed an issue normalizing CPU architecture in the configure script,
          which disabled assembly optimizations on platforms that get detected
          as 'amd64', opposed to 'x86_64'

        * Limited tls_config_clear_keys() to only clear private keys.
          This was inadvertently clearing the keypair, which includes the OCSP
          staple and pubkey hash - if an application called tls_configure()
          followed by tls_config_clear_keys(), this would prevent OCSP staples
          from working.

2.7.2 - Stable release

        * Updated and added extensive new HISTORY sections to API manuals.

        * Added support for shared library builds with CMake on all supported
          platforms. Note that some of the CMake options have changed, consult
          the README for details.

2.7.1 - Bug fixes

        * Fixed a bug in int_x509_param_set_hosts, calling strlen() if name
          length provided is 0 to match the OpenSSL behaviour. Issue noticed
          by Christian Heimes <christian@python.org>.

        * Fixed builds macOS 10.11 and older.

2.7.0 - Bug fixes and improvements

        * Added support for many OpenSSL 1.0.2 and 1.1 APIs, based on
          observations of real-world usage in applications. These are
          implemented in parallel with existing OpenSSL 1.0.1 APIs - visibility
          changes have not been made to existing structs, allowing code written
          for older OpenSSL APIs to continue working.

        * Extensive corrections, improvements, and additions to the
          API documentation, including new public APIs from OpenSSL that had
          no pre-existing documentation.

        * Added support for automatic library initialization in libcrypto,
          libssl, and libtls. Support for pthread_once or a compatible
          equivalent is now required of the target operating system. As a
          side-effect, minimum Windows support is Vista or higher.

        * Converted more packet handling methods to CBB, which improves
          resiliency when generating TLS messages.

        * Completed TLS extension handling rewrite, improving consistency of
          checks for malformed and duplicate extensions.

        * Rewrote ASN1_TYPE_{get,set}_octetstring() using templated ASN.1.
          This removes the last remaining use of the old M_ASN1_* macros
          (asn1_mac.h) from API that needs to continue to exist.

        * Added support for client-side session resumption in libtls.
          A libtls client can specify a session file descriptor (a regular
          file with appropriate ownership and permissions) and libtls will
          manage reading and writing of session data across TLS handshakes.

        * Improved support for strict alignment on ARMv7 architectures,
          conditionally enabling assembly in those cases.

        * Fixed a memory leak in libtls when reusing a tls_config.

        * Merged more DTLS support into the regular TLS code path, removing
          duplicated code.

        * Many improvements to Windows Cmake-based builds and tests,
          especially when targeting Visual Studio.

2.6.4 - Bug fixes

        * Make tls_config_parse_protocols() work correctly when passed a NULL
          pointer for a protocol string. Issue found by semarie@, who also
          provided the diff.

        * Correct TLS extensions handling when no extensions are present.
          If no TLS extensions are present in a client hello or server hello,
          omit the entire extensions block, rather than including it with a
          length of zero. Thanks to Eric Elena <eric at voguemerry dot com> for
          providing packet captures and testing the fix.

        * Fixed portable builds on older Android systems, and systems with out
          IPV6_TCLASS support.

2.6.3 - OpenBSD 6.2 Release

        * No core changes from LibreSSL 2.6.2

        * Minor compatibility fixes in portable version.

2.6.2 - Bug fixes

        * Provide a useful error with libtls if there are no OCSP URLs in a
          peer certificate.

        * Keep track of which keypair is in use by a TLS context, fixing a bug
          where a TLS server with SNI would only return the OCSP staple for the
          default keypair. Issue reported by William Graeber and confirmed by
          Andreas Bartelt.

        * Fixed various issues in the OCSP extension parsing code.
          The original code incorrectly passes the pointer allocated via
          CBS_stow() (using malloc()) to a d2i_*() function and then calls
          free() on the now incremented pointer, most likely resulting in a
          crash. This issue was reported by Robert Swiecki who found the issue
          using honggfuzz.

        * If tls_config_parse_protocols() is called with a NULL pointer,
          return the default protocols instead of crashing - this makes the
          behaviour more useful and mirrors what we already do in
          tls_config_set_ciphers() et al.

2.6.1 - Code removal, rewrites

        * Added a "-T tlscompat" option to nc(1), which enables the use of all
          TLS protocols and "compat" ciphers. This allows for TLS connections
          to TLS servers that are using less than ideal cipher suites, without
          having to resort to "-T tlsall" which enables all known cipher
          suites.  Diff from Kyle J. McKay.

        * Added a new TLS extension handling framework, somewhat analogous to
          BoringSSL, and converted all TLS extensions to use it. Added new TLS
          extension regression tests.

        * Improved and added many new manpages. Updated *check_private_key
          manpages with additional cautions regarding their use.

        * Cleaned up the EC key/curve configuration handling.

        * Added tls_config_set_ecdhecurves() to libtls, which allows the names
          of the eliptical curves that may be used during client and server
          key exchange to be specified.

        * Converted more code paths to use CBB/CBS.

        * Removed support for DSS/DSA, since we removed the cipher suites a
          while back.

        * Removed NPN support. NPN was never standardised and the last draft
          expired in October 2012. ALPN was standardised in July 2014 and has
          been supported in LibreSSL since December 2014. NPN has also been
          removed from Chromium in May 2016.

        * Removed SSL_OP_CRYPTOPRO_TLSEXT_BUG workaround for old/broken
          CryptoPro clients.

        * Removed support for the TLS padding extension, which was added as a
          workaround for an old bug in F5's TLS termination.

        * Worked around another bug in F5's TLS termination handling of the
          elliptical curves extension. RFC 4492 only defines elliptic_curves
          for ClientHello. However, F5 is sending it in ServerHello.  We need
          to skip over it since our TLS extension parsing code is now more
          strict. Thanks to Armin Wolfermann and WJ Liu for reporting.

        * Added ability to clamp notafter valies in certificates for systems
          with 32-bit time_t. This is necessary to conform to RFC 5280
          4.1.2.5.

        * Implemented the SSL_CTX_set_min_proto_version(3) API.

        * Removed the original (pre-IETF) chacha20-poly1305 cipher suites.

        * Reclassified ECDHE-RSA-DES-CBC3-SHA from HIGH to MEDIUM.

2.6.0 - New APIs, bug fixes and improvements

        * Added support for providing CRLs to libtls. Once a CRL is provided we
          enable CRL checking for the full certificate chain. Based on a diff
          from Jack Burton

        * Allow non-compliant clients using IP literal addresses with SNI
          to connect to a server using libtls.

        * Avoid a potential NULL pointer dereference in d2i_ECPrivateKey().
          Reported by Robert Swiecki, who found the issue using honggfuzz.

        * Added definitions for three OIDs used in EV certificates.
          From Kyle J. McKay

        * Added tls_peer_cert_chain_pem to libtls, useful in private
          certificate validation callbacks such as those in relayd.

        * Converted explicit clear/free sequences to use freezero(3).

        * Reworked TLS certificate name verification code to more strictly
          follow RFC 6125.

        * Cleaned up and simplified server key exchange EC point handling.

        * Added tls_keypair_clear_key for clearing key material.

        * Removed inconsistent IPv6 handling from BIO_get_accept_socket,
          simplified BIO_get_host_ip and BIO_accept.

        * Fixed the openssl(1) ca command so that is generates certificates
          with RFC 5280-conformant time. Problem noticed by Harald Dunkel.

        * Added ASN1_TIME_set_tm to set an asn1 from a struct tm *

        * Added SSL{,_CTX}_set_{min,max}_proto_version() functions.

        * Added HKDF (HMAC Key Derivation Function) from BoringSSL

        * Provided a tls_unload_file() function that frees the memory returned
          from a tls_load_file() call, ensuring that it the contents become
          inaccessible. This is specifically needed on platforms where the
          library allocators may be different from the application allocator.

        * Perform reference counting for tls_config. This allows
          tls_config_free() to be called as soon as it has been passed to the
          final tls_configure() call, simplifying lifetime tracking for the
          application.

        * Moved internal state of SSL and other structures to be opaque.

        * Dropped cipher suites with DSS authentication.

        * nc(1) improvements, including:
           nc -W to terminate nc after receiving a number of packets
           nc -Z for saving the peer certificate and chain in a pem file

2.5.5 - Bug fixes

        * Distinguish between self-issued certificates and self-signed
          certificates. The certificate verification code has special cases
          for self-signed certificates and without this change, self-issued
          certificates (which it seems are common place with
          openvpn/easyrsa) were also being included in this category.

        * Added getpagesize fallback, needed for Android bionic libc.

2.5.4 - Security Updates

        * Revert a previous change that forced consistency between return
          value and error code when specifing a certificate verification
          callback, since this breaks the documented API. When a user supplied
          callback always returns 1, and later code checks the error code to
          potentially abort post verification, this will result in incorrect
          successul certificate verification.

        * Switched Linux getrandom() usage to non-blocking mode, continuing to
          use fallback mechanims if unsuccessful. This works around a design
          flaw in Linux getrandom(2) where early boot usage in a library makes
          it impossible to recover if getrandom(2) is not yet initialized.

        * Fixed a bug caused by the return value being set early to signal
          successful DTLS cookie validation. This can mask a later failure and
          result in a positive return value being returned from
          ssl3_get_client_hello(), when it should return a negative value to
          propagate the error.

        * Fixed a build error on non-x86/x86_64 systems running Solaris.

2.5.3 - OpenBSD 6.1 Release

        * Documentation updates

        * Improved ocspcheck(1) error handling

2.5.2 - Security features and bugfixes

        * Added the recallocarray(3) memory allocation function, and converted
          various places in the library to use it, such as CBB and BUF_MEM_grow.
          recallocarray(3) is similar to reallocarray. Newly allocated memory
          is cleared similar to calloc(3). Memory that becomes unallocated
          while shrinking or moving existing allocations is explicitly
          discarded by unmapping or clearing to 0

        * Added new root CAs from SECOM Trust Systems / Security Communication
          of Japan.

        * Added EVP interface for MD5+SHA1 hashes.

        * Fixed DTLS client failures when the server sends a certificate
          request.

        * Correct handling of padding when upgrading an SSLv2 challenge into
          an SSLv3/TLS connection.

        * Allow protocols and ciphers to be set on a TLS config object in
          libtls.

        * Improved nc(1) TLS handshake CPU usage and server-side error
          reporting.

2.5.1 - Bug and security fixes, new features, documentation updates

        * X509_cmp_time() now passes a malformed GeneralizedTime field as an
          error. Reported by Theofilos Petsios.

        * Detect zero-length encrypted session data early, instead of when
          malloc(0) fails or the HMAC check fails. Noted independently by
          jsing@ and Kurt Cancemi.

        * Check for and handle failure of HMAC_{Update,Final} or
          EVP_DecryptUpdate().

        * Massive update and normalization of manpages, conversion to
          mandoc format. Many pages were rewritten for clarity and accuracy.
          Portable doc links are up-to-date with a new conversion tool.

        * Curve25519 Key Exchange support.

        * Support for alternate chains for certificate verification.

        * Code cleanups, CBS conversions, further unification of DTLS/SSL
          handshake code, further ASN1 macro expansion and removal.

        * Private symbol are now hidden in libssl and libcryto.

        * Friendly certificate verification error messages in libtls, peer
          verification is now always enabled.

        * Added OCSP stapling support to libtls and netcat.

        * Added ocspcheck utility to validate a certificate against its OCSP
          responder and save the reply for stapling

        * Enhanced regression tests and error handling for libtls.

        * Added explicit constant and non-constant time BN functions,
          defaulting to constant time wherever possible.

        * Moved many leaked implementation details in public structs behind
          opaque pointers.

        * Added ticket support to libtls.

        * Added support for setting the supported EC curves via
          SSL{_CTX}_set1_groups{_list}() - also provide defines for the previous
          SSL{_CTX}_set1_curves{_list} names. This also changes the default
          list of curves to be X25519, P-256 and P-384. All other curves must
          be manually enabled.

        * Added -groups option to openssl(1) s_client for specifying the curves
          to be used in a colon-separated list.

        * Merged client/server version negotiation code paths into one,
          reducing much duplicate code.

        * Removed error function codes from libssl and libcrypto.

        * Fixed an issue where a truncated packet could crash via an OOB read.

        * Added SSL_OP_NO_CLIENT_RENEGOTIATION option that disallows
          client-initiated renegotiation. This is the default for libtls
          servers.

        * Avoid a side-channel cache-timing attack that can leak the ECDSA
          private keys when signing. This is due to BN_mod_inverse() being
          used without the constant time flag being set. Reported by Cesar
          Pereida Garcia and Billy Brumley (Tampere University of Technology).
          The fix was developed by Cesar Pereida Garcia.

        * iOS and MacOS compatibility updates from Simone Basso and Jacob
          Berkman.


2.5.0 - New APIs, bug fixes and improvements

        * libtls now supports ALPN and SNI

        * libtls adds a new callback interface for integrating custom IO
          functions. Thanks to Tobias Pape.

        * libtls now handles 4 cipher suite groups:
            "secure" (TLSv1.2+AEAD+PFS)
            "compat" (HIGH:!aNULL)
            "legacy" (HIGH:MEDIUM:!aNULL)
            "insecure" (ALL:!aNULL:!eNULL)

            This allows for flexibility and finer grained control, rather than
            having two extremes (an issue raised by Marko Kreen some time ago).

        * Tightened error handling for tls_config_set_ciphers().

        * libtls now always loads CA, key and certificate files at the time the
          configuration function is called. This simplifies code and results in
          a single memory based code path being used to provide data to libssl.

        * Add support for OCSP intermediate certificates.

        * Added functions used by stunnel and exim from BoringSSL - this
          brings in X509_check_host, X509_check_email, X509_check_ip, and
          X509_check_ip_asc.

        * Added initial support for iOS, thanks to Jacob Berkman.

        * Improved behavior of arc4random on Windows when using memory leak
          analysis software.

        * Correctly handle an EOF that occurs prior to the TLS handshake
          completing. Reported by Vasily Kolobkov, based on a diff from Marko
          Kreen.

        * Limit the support of the "backward compatible" ssl2 handshake to
          only be used if TLS 1.0 is enabled.

        * Fix incorrect results in certain cases on 64-bit systems when
          BN_mod_word() can return incorrect results. BN_mod_word() now can
          return an error condition. Thanks to Brian Smith.

        * Added constant-time updates to address CVE-2016-0702

        * Fixed undefined behavior in BN_GF2m_mod_arr()

        * Removed unused Cryptographic Message Support (CMS)

        * More conversions of long long idioms to time_t

        * Improved compatibility by avoiding printing NULL strings with
          printf.

        * Reverted change that cleans up the EVP cipher context in
          EVP_EncryptFinal() and EVP_DecryptFinal(). Some software relies on the
          previous behaviour.

        * Avoid unbounded memory growth in libssl, which can be triggered by a
          TLS client repeatedly renegotiating and sending OCSP Status Request
          TLS extensions.

        * Avoid falling back to a weak digest for (EC)DH when using SNI with
          libssl.

2.4.2 - Bug fixes and improvements

        * Fixed loading default certificate locations with openssl s_client.

        * Ensured OCSP only uses and compares GENERALIZEDTIME values as per
          RFC6960. Also added fixes for OCSP to work with intermediate
          certificates provided in responses.

        * Improved behavior of arc4random on Windows to not appear to leak
          memory in debug tools, reduced privileges of allocated memory.

        * Fixed incorrect results from BN_mod_word() when the modulus is too
          large, thanks to Brian Smith from BoringSSL.

        * Correctly handle an EOF prior to completing the TLS handshake in
          libtls.

        * Improved libtls ceritificate loading and cipher string validation.

        * Updated libtls cipher group suites into four categories:
            "secure"   (TLSv1.2+AEAD+PFS)
            "compat"   (HIGH:!aNULL)
            "legacy"   (HIGH:MEDIUM:!aNULL)
            "insecure" (ALL:!aNULL:!eNULL)
          This allows for flexibility and finer grained control, rather than
          having two extremes.

        * Limited support for 'backward compatible' SSLv2 handshake packets to
          when TLS 1.0 is enabled, providing more restricted compatibility
          with TLS 1.0 clients.

        * openssl(1) and other documentation improvements.

        * Removed flags for disabling constant-time operations.
          This removes support for DSA_FLAG_NO_EXP_CONSTTIME,
          DH_FLAG_NO_EXP_CONSTTIME, and RSA_FLAG_NO_CONSTTIME flags, making
          all of these operations unconditionally constant-time.


2.4.1 - Security fix

        * Correct a problem that prevents the DSA signing algorithm from
          running in constant time even if the flag BN_FLG_CONSTTIME is set.
          This issue was reported by Cesar Pereida (Aalto University), Billy
          Brumley (Tampere University of Technology), and Yuval Yarom (The
          University of Adelaide and NICTA). The fix was developed by Cesar
          Pereida.

2.4.0 - Build improvements, new features

        * Many improvements to the CMake build infrastructure, including
          Solaris, mingw-w64, Cygwin, and HP-UX support. Thanks to Kinichiro
          Inoguchi for this work.

        * Added missing error handling around bn_wexpand() calls.

        * Added explicit_bzero calls for freed ASN.1 objects.

        * Fixed X509_*set_object functions to return 0 on allocation failure.

        * Implemented the IETF ChaCha20-Poly1305 cipher suites.

        * Changed default EVP_aead_chacha20_poly1305() implementation to the
          IETF version, which is now the default.

        * Fixed password prompts from openssl(1) to properly handle ^C.

        * Reworked error handling in libtls so that configuration errors are
          visible.

        * Deprecated internal use of EVP_[Cipher|Encrypt|Decrypt]_Final.

        * Manpage fixes and updates

2.3.5 - Reliability fix

        * Fixed an error in libcrypto when parsing some ASN.1 elements > 16k.

2.3.4 - Security Update

        * Fix multiple vulnerabilities in libcrypto relating to ASN.1 and encoding.
        From OpenSSL.

        * Minor build fixes

2.3.3 - OpenBSD 5.9 release branch tagged

        * Reworked build scripts to better sync with OpenNTPD-portable

        * Fixed broken manpage links

        * Fixed an nginx compatibility issue by adding an 'install_sw' make alias

        * Fixed HP-UX builds

        * Changed the default configuration directory to c:\LibreSSL\ssl on Windows
          binary builds

        * cert.pem has been reorganized and synced with Mozilla's certificate store

2.3.2 - Compatibility and Reliability fixes

        * Changed format of LIBRESSL_VERSION_NUMBER to match that of
          OPENSSL_VERSION_NUMBER, see:
          https://wiki.openssl.org/index.php/Manual:OPENSSL_VERSION_NUMBER(3)

        * Added EVP_aead_chacha20_poly1305_ietf() which matches the AEAD
          construction introduced in RFC 7539, which is different than that
          already used in TLS with EVP_aead_chacha20_poly1305()

        * Avoid a potential undefined C99+ behavior due to shift overflow in
          AES_decrypt, reported by Pascal Cuoq <cuoq at trust-in-soft.com>

        * More man pages converted from pod to mdoc format

        * Added COMODO RSA Certification Authority and QuoVadis
          root certificates to cert.pem

        * Removed Remove "C=US, O=VeriSign, Inc., OU=Class 3 Public Primary Certification
          Authority" (serial 3c:91:31:cb:1f:f6:d0:1b:0e:9a:b8:d0:44:bf:12:be) root
          certificate from cert.pem

        * Added support for building nc(1) on Solaris

        * Fixed GCC 5.x+ preprocessor checks, reported by Ruslan Babayev

        * Improved console handling with openssl(1) on Windows

        * Ensure the network stack is enabled on Windows when running
          tls_init()

        * Fixed incorrect TLS certificate loading by nc(1)

        * Added support for Solaris 11.3's getentropy(2) system call

        * Enabled support for using NetBSD 7.0's arc4random(3) implementation

        * Deprecated the SSL_OP_SINGLE_DH_USE flag by disabling its effect

        * Fixes from OpenSSL 1.0.1q
         - CVE-2015-3194 - NULL pointer dereference in client side certificate
                           validation.
         - CVE-2015-3195 - Memory leak in PKCS7 - not reachable from TLS/SSL

        * The following OpenSSL CVEs did not apply to LibreSSL
         - CVE-2015-3193 - Carry propagating bug in the x86_64 Montgomery
                           squaring procedure.
         - CVE-2015-3196 - Double free race condition of the identify hint
                           data.

         See https://marc.info/?l=openbsd-announce&m=144925068504102

2.3.1 - ASN.1 and time handling cleanups

        * ASN.1 cleanups and RFC5280 compliance fixes.

        * Time representations switched from 'unsigned long' to 'time_t'. LibreSSL
          now checks if the host OS supports 64-bit time_t.

        * Fixed a leak in SSL_new in the error path.

        * Support always extracting the peer cipher and version with libtls.

        * Added ability to check certificate validity times with libtls,
          tls_peer_cert_notbefore and tls_peer_cert_notafter.

        * Changed tls_connect_servername to use the first address that resolves with
          getaddrinfo().

        * Remove broken conditional EVP_CHECK_DES_KEY code (non-functional since
          initial commit in 2004).

        * Fixed a memory leak and out-of-bounds access in OBJ_obj2txt, reported
          by Qualys Security.

        * Fixed an up-to 7 byte overflow in RC4 when len is not a multiple of
          sizeof(RC4_CHUNK), reported by Pascal Cuoq <cuoq at trust-in-soft.com>.

        * Reject too small bits value in BN_generate_prime_ex(), so that it does
          not risk becoming negative in probable_prime_dh_safe(), reported by
                Franck Denis.

        * Enable nc(1) builds on more platforms.

2.3.0 - SSLv3 removed, libtls API changes, portability improvements

        * SSLv3 is now permanently removed from the tree.

        * The libtls API is changed from the 2.2.x series.

          The read/write functions work correctly with external event
          libraries.  See the tls_init man page for examples of using libtls
          correctly in asynchronous mode.

          Client-side verification is now supported, with the client supplying
          the certificate to the server.

          Also, when using tls_connect_fds, tls_connect_socket or
          tls_accept_fds, libtls no longer implicitly closes the passed in
          sockets. The caller is responsible for closing them in this case.

        * When loading a DSA key from an raw (without DH parameters) ASN.1
          serialization, perform some consistency checks on its `p' and `q'
          values, and return an error if the checks failed.

          Thanks for Georgi Guninski (guninski at guninski dot com) for
          mentioning the possibility of a weak (non prime) q value and
          providing a test case.

          See
          https://cpunks.org/pipermail/cypherpunks/2015-September/009007.html
          for a longer discussion.

        * Fixed a bug in ECDH_compute_key that can lead to silent truncation
          of the result key without error. A coding error could cause software
          to use much shorter keys than intended.

        * Removed support for DTLS_BAD_VER. Pre-DTLSv1 implementations are no
          longer supported.

        * The engine command and parameters are removed from the openssl(1).
          Previous releases removed dynamic and builtin engine support
          already.

        * SHA-0 is removed, which was withdrawn shortly after publication 20
          years ago.

        * Added Certplus CA root certificate to the default cert.pem file.

        * New interface OPENSSL_cpu_caps is provided that does not allow
          software to inadvertently modify cpu capability flags.
          OPENSSL_ia32cap and OPENSSL_ia32cap_loc are removed.

        * The out_len argument of AEAD changed from ssize_t to size_t.

        * Deduplicated DTLS code, sharing bugfixes and improvements with
          TLS.

        * Converted 'nc' to use libtls for client and server operations; it is
          included in the libressl-portable distribution as an example of how
          to use the library.

2.2.3 - Bug fixes, build enhancements

        * LibreSSL 2.2.2 incorrectly handles ClientHello messages that do not
          include TLS extensions, resulting in such handshakes being aborted.
          This release corrects the handling of such messages. Thanks to
          Ligushka from github for reporting the issue.

        * Added install target for cmake builds. Thanks to TheNietsnie from
          github.

        * Updated pkgconfig files to correctly report the release version
          number, not the individual library ABI version numbers. Thanks to
          Jan Engelhardt for reporting the issue.

2.2.2 - More TLS parser rework, bug fixes, expanded portable build support

        * Switched 'openssl dhparam' default from 512 to 2048 bits

        * Reworked openssl(1) option handling

        * More CRYPTO ByteString (CBC) packet parsing conversions

        * Fixed 'openssl pkeyutl -verify' to exit with a 0 on success

        * Fixed dozens of Coverity issues including dead code, memory leaks,
          logic errors and more.

        * Ensure that openssl(1) restores terminal echo state after reading a
          password.

        * Incorporated fix for OpenSSL Issue #3683

        * LibreSSL version define LIBRESSL_VERSION_NUMBER will now be bumped
          for each portable release.

        * Removed workarounds for TLS client padding bugs.

        * No longer disable ECDHE-ECDSA on OS X

        * Removed SSLv3 support from openssl(1)

        * Removed IE 6 SSLv3 workarounds.

        * Modified tls_write in libtls to allow partial writes, clarified with
          examples in the documentation.

        * Removed RSAX engine

        * Tested SSLv3 removal with the OpenBSD ports tree and found several
          applications that were not ready to build without SSLv3 yet. For
          now, building a program that intentionally uses SSLv3 will result in
          a linker warning.

        * Added TLS_method, TLS_client_method and TLS_server_method as a
          replacement for the SSLv23_*method calls.

        * Added initial cmake build support, including support for building with
          Visual Studio, currently tested with Visual Studio 2013 Community
          Edition.

        * --with-enginesdir is removed as a configuration parameter

        * Default cert.pem, openssl.cnf, and x509v3.cnf files are now
          installed under $sysconfdir/ssl or the directory specified by
          --with-openssldir. Previous versions of LibreSSL left these empty.

2.2.1 - Build fixes, feature added, features removed

        * Assorted build fixes for musl, HP-UX, Mingw, Solaris.

        * Initial support for Windows Embedded 2009, Server 2003, XP

        * Protocol parsing conversions to BoringSSL's CRYPTO ByteString (CBS) API

        * Added EC_curve_nid2nist and EC_curve_nist2nid from OpenSSL

        * Removed Dynamic Engine support

        * Removed unused and obsolete MDC-2DES cipher

        * Removed workarounds for obsolete SSL implementations

2.2.0 - Build cleanups and new OS support, Security Updates

        * AIX Support - thanks to Michael Felt

        * Cygwin Support - thanks to Corinna Vinschen

        * Refactored build macros, support packaging libtls independently.
          There are more pieces required to support building and using OpenSSL
          with libtls, but this is an initial start at providing an
          independent package for people to start hacking on.

        * Removal of OPENSSL_issetugid and all library getenv calls.
          Applications can and should no longer rely on environment variables
          for changing library behavior. OPENSSL_CONF/SSLEAY_CONF is still
          supported with the openssl(1) command.

        * libtls API and documentation additions

        * Various bug fixes and simplifications to libssl and libcrypto

        * Fixes for the following issues are integrated into LibreSSL 2.2.0:
         - CVE-2015-1788 - Malformed ECParameters causes infinite loop
         - CVE-2015-1789 - Exploitable out-of-bounds read in X509_cmp_time
         - CVE-2015-1792 - CMS verify infinite loop with unknown hash function

        * The following CVEs did not apply to LibreSSL or were fixed in
          earlier releases:
         - CVE-2015-4000 - DHE man-in-the-middle protection (Logjam)
         - CVE-2015-1790 - PKCS7 crash with missing EnvelopedContent
         - CVE-2014-8176 - Invalid free in DTLS

        * Fixes for the following CVEs are still in review for LibreSSL
         - CVE-2015-1791 - Race condition handling NewSessionTicket

2.1.6 - Security update

        * Fixes for the following issues are integrated into LibreSSL 2.1.6:
          - CVE-2015-0209 - Use After Free following d2i_ECPrivatekey error
          - CVE-2015-0286 - Segmentation fault in ASN1_TYPE_cmp
          - CVE-2015-0287 - ASN.1 structure reuse memory corruption
          - CVE-2015-0288 - X509_to_X509_REQ NULL pointer deref
          - CVE-2015-0289 - PKCS7 NULL pointer dereferences

        * The fix for CVE-2015-0207 - Segmentation fault in DTLSv1_listen
          is integrated for safety, but LibreSSL is not vulnerable.

        * Libtls is now built by default. The --enable-libtls
          configuration option is no longer required.
          The libtls API is now stable for the 2.1.x series.

2.1.5 - Bug fixes and a security update
        * Fix incorrect comparison function in openssl(1) certhash command.
          Thanks to Christian Neukirchen / Void Linux.

        * Windows port improvements and bug fixes.
          - Removed a dependency on libgcc in 32-bit dynamic libraries.
          - Correct a hang in openssl(1) reading from stdin on an connection.
          - Initialize winsock in openssl(1) earlier, allow 'openssl ocsp' and
            any other network-related commands to function properly.

        * Reject all server DH keys smaller than 1024 bits.

2.1.4 - Security and feature updates
        * Improvements to libtls:
          - a new API for loading CA chains directly from memory instead of a
            file, allowing verification with privilege separation in a chroot
            without direct access to CA certificate files.

          - Ciphers default to TLSv1.2 with AEAD and PFS.

          - Improved error handling and message generation

          - New APIs and improved documentation

        * Added X509_STORE_load_mem API for loading certificates from memory.
          This facilitates accessing certificates from a chrooted environment.

        * New AEAD "MAC alias" allows configuring TLSv1.2 AEAD ciphers by
          using 'TLSv1.2+AEAD' as the cipher selection string.

        * Dead and disabled code removal including MD5, Netscape workarounds,
          non-POSIX IO, SCTP, RFC 3779 support, many #if 0 sections, and more.

        * ASN1 macro maze expanded to aid reading and searching the code.

        * NULL pointer asserts removed in favor of letting the OS/signal
          handler catch them.

        * Refactored argument handling in openssl(1) for consistency and
          maintainability.

        * New openssl(1) command 'certhash' replaces the c_rehash script.

        * Support for building with OPENSSL_NO_DEPRECATED

        * Server-side support for TLS_FALLBACK_SCSV for compatibility with
          various auditor and vulnerability scanners.

        * Dozens of issues found with the Coverity scanner fixed.

        * Security Updates:

          - Fix a minor information leak that was introduced in t1_lib.c
            r1.71, whereby an additional 28 bytes of .rodata (or .data) is
            provided to the network. In most cases this is a non-issue since
            the memory content is already public. Issue found and reported by
            Felix Groebert of the Google Security Team.

          - Fixes for the following low-severity issues were integrated into
            LibreSSL from OpenSSL 1.0.1k:

             CVE-2015-0205 - DH client certificates accepted without
                             verification
             CVE-2014-3570 - Bignum squaring may produce incorrect results
             CVE-2014-8275 - Certificate fingerprints can be modified
             CVE-2014-3572 - ECDHE silently downgrades to ECDH [Client]
             Reported by Karthikeyan Bhargavan of the PROSECCO team at INRIA.

            The following CVEs were fixed in earlier LibreSSL releases:
             CVE-2015-0206 - Memory leak handling repeated DLTS records
             CVE-2014-3510 - Flaw handling DTLS anonymous EC(DH) ciphersuites.

            The following CVEs did not apply to LibreSSL:
             CVE-2014-3571 - DTLS segmentation fault in dtls1_get_record
             CVE-2014-3569 - no-ssl3 configuration sets method to NULL
             CVE-2015-0204 - RSA silently downgrades to EXPORT_RSA

2.1.3 - Security update and OS support improvements
        * Fixed various memory leaks in DTLS, including fixes for
          CVE-2015-0206.

        * Added Application-Layer Protocol Negotiation (ALPN) support.

        * Removed GOST R 34.10-94 signature authentication.

        * Removed nonfunctional Netscape browser-hang workaround code.

        * Simplified and refactored SSL/DTLS handshake code.

        * Added SHA256 Camellia cipher suites for TLS 1.2 from RFC 5932.

        * Hide timing info about padding errors during handshakes.

        * Improved libtls support for non-blocking sockets, added randomized
          session ID contexts. Work is ongoing with this library - feedback
          and potential use-cases are welcome.

        * Support building Windows DLLs.
          Thanks to Jan Engelhard.

        * Packaged config wrapper for better compatibility with OpenSSL-based
          build systems.
          Thanks to @technion from github

        * Ensure the stack is marked non-executable for assembly sections.
          Thanks to Anthony G. Bastile.

        * Enable extra compiler hardening flags by default, where applicable.
          The default set of hardening features can vary by OS to OS, so
          feedback is welcome on this. To disable the default hardening flags,
          specify '--disable-hardening' during configure.
          Thanks to Jim Barlow

        * Initial HP-UX support, tested with HP-UX 11.31 ia64
          Thanks to Kinichiro Inoguchi

        * Initial NetBSD support, tested with NetBSD 6.1.5 x86_64
          Imported from OpenNTPD, thanks to @gitisihara from github

2.1.2 - Many new features and improvements
        * Added reworked GOST cipher suite support
           thanks to Dmitry Eremin-Solenikov

        * Enabled Camellia ciphers due to improved patent situation

        * Use builtin arc4random implementation on OS X and FreeBSD
           this addresses some deficiencies in the native implementations of
           these operating systems, see commit logs for more information

        * Added initial Windows mingw-w64 support (32 and 64-bit)
           thanks to Song Dongsheng and others for code and feedback

        * Enabled assembly optimizations on x86_64 CPUs
           supports Linux, *BSD, Solaris and OS X operating systems
           thanks to Wouter Clarie for the initial implementation

        * Added no_ssl3/no_tls1_1/no_tls1_2 options to openssl(1)

        * Improved build infrastructure, 'make distcheck' now passes
           this simplifies and speeds developer efficiency
           thanks to Dmitry Eremin-Solenikov and Wouter Clarie

        * Allow conditional building of the libtls library
           expect the API and ABI of the library to change
           feedback is welcome

        * Fixes for more memory leaks, cleanups, etc.

2.1.1 - Security update
        * Address POODLE attack by disabling SSLv3 by default

        * Fix Eliptical Curve cipher selection bug
          (https://github.com/libressl-portable/portable/issues/35)

2.1.0 - First release from the OpenBSD 5.7 tree
        * Added support for automatic ephemeral EC keys

        * Fixes for many memory leaks and overflows in error handlers

        * The TLS padding extension (that works around bugs in F5 terminators) is
          off by default

        * support for getrandom(2) on Linux 3.17

        * the NO_ASM macro is no longer being set, providing the first bits toward
          enabling other assembly offloads.

2.0.5 - Fixes for CVEs from OpenSSL 1.0.1i
        * CVE-2014-3506
        * CVE-2014-3507
        * CVE-2014-3508 (partially vulnerable)he
        * CVE-2014-3509
        * CVE-2014-3510
        * CVE-2014-3511
        * Synced LibreSSL Portable with the release version of OpenBSD 5.6

2.0.4 - Portability fixes, deleted unused SRP code

2.0.3 - Portability fixes, improvements to fork detection

2.0.2 - Address arc4random fork PID wraparound issues with pthread_atfork

2.0.1 - Portability fixes:
        * Removed -Werror and and other non-portable compiler flags

        * Allow setting OPENSSLDIR and ENGINSDIR

2.0.0 - First release from the OpenBSD 5.6 tree
        * Removal of many obsolete features and coding conventions from the OpenSSL
          1.0.1h source