NEWS

GnuTLS NEWS -- History of user-visible changes.                -*- outline -*-
Bug numbers referenced in this log correspond to bug numbers at our issue tracker,
available at https://gitlab.com/gnutls/gnutls/issues
Copyright (C) 2000-2016 Free Software Foundation, Inc.
Copyright (C) 2013-2019 Nikos Mavrogiannopoulos
See the end for copying conditions.

* Version 3.7.9 (released 2023-02-09)

** libgnutls: Fix a Bleichenbacher oracle in the TLS RSA key exchange.
   Reported by Hubert Kario (#1050). Fix developed by Alexander Sosedkin.
   [GNUTLS-SA-2020-07-14, CVSS: medium] [CVE-2023-0361]

** API and ABI modifications:
No changes since last version.

* Version 3.7.8 (released 2022-09-27)

** libgnutls: In FIPS140 mode, RSA signature verification is an approved
   operation if the key has modulus with known sizes (1024, 1280,
   1536, and 1792 bits), in addition to any modulus sizes larger than
   2048 bits, according to SP800-131A rev2.

** libgnutls: gnutls_session_channel_binding performs additional checks when
   GNUTLS_CB_TLS_EXPORTER is requested. According to RFC9622 4.2, the
   "tls-exporter" channel binding is only usable when the handshake is
   bound to a unique master secret (i.e., either TLS 1.3 or extended
   master secret extension is negotiated). Otherwise the function now
   returns error.

** libgnutls: usage of the following functions, which are designed to
   loosen restrictions imposed by allowlisting mode of configuration,
   has been additionally restricted. Invoking them is now only allowed
   if system-wide TLS priority string has not been initialized yet:
gnutls_digest_set_secure
gnutls_sign_set_secure
gnutls_sign_set_secure_for_certs
gnutls_protocol_set_enabled

** API and ABI modifications:
No changes since last version.

* Version 3.7.7 (released 2022-07-28)

** libgnutls: Fixed double free during verification of pkcs7 signatures.
   Reported by Jaak Ristioja (#1383). [GNUTLS-SA-2022-07-07, CVSS: medium]
   [CVE-2022-2509]

** libgnutls: gnutls_hkdf_expand now only accepts LENGTH argument less than or
   equal to 255 times hash digest size, to comply with RFC 5869 2.3.

** libgnutls: Length limit for TLS PSK usernames has been increased
   from 128 to 65535 characters (#1323).

** libgnutls: AES-GCM encryption function now limits plaintext
   length to 2^39-256 bits, according to SP800-38D 5.2.1.1.

** libgnutls: New block cipher functions have been added to transparently
   handle padding.  gnutls_cipher_encrypt3 and gnutls_cipher_decrypt3 can be
   used in combination of GNUTLS_CIPHER_PADDING_PKCS7 flag to automatically
   add/remove padding if the length of the original plaintext is not a multiple
   of the block size.

** libgnutls: New function for manual FIPS self-testing.

** API and ABI modifications:
gnutls_fips140_run_self_tests: New function
gnutls_cipher_encrypt3: New function
gnutls_cipher_decrypt3: New function
gnutls_cipher_padding_flags_t: New enum

** guile: Guile 1.8 is no longer supported

** guile: Session record port treats premature termination as EOF
   Previously, a ‘gnutls-error’ exception with the
   ‘error/premature-termination’ value would be thrown while reading from a
   session record port when the underlying session was terminated
   prematurely.  This was inconvenient since users of the port may not be
   prepared to handle such an exception.
   Reading from the session record port now returns the end-of-file object
   instead of throwing an exception, just like it would for a proper
   session termination.

** guile: Session record ports can have a ‘close’ procedure.
   The ‘session-record-port’ procedure now takes an optional second
   parameter, and a new ‘set-session-record-port-close!’ procedure is
   provided to specify a ‘close’ procedure for a session record port.
   This ‘close’ procedure lets users specify cleanup operations for when
   the port is closed, such as closing the file descriptor or port that
   backs the underlying session.

* Version 3.7.6 (released 2022-05-27)

** libgnutls: Fixed invalid write when gnutls_realloc_zero()
   is called with new_size < old_size. This bug caused heap
   corruption when gnutls_realloc_zero() has been set as gmp
   reallocfunc (!1592, #1367, #1368, #1369).

** API and ABI modifications:
No changes since last version.

* Version 3.7.5 (released 2022-05-15)

** libgnutls: The GNUTLS_NO_TICKETS_TLS12 flag and %NO_TICKETS_TLS12 priority
   modifier have been added to disable session ticket usage in TLS 1.2 because
   it does not provide forward secrecy (#477).  On the other hand, since session
   tickets in TLS 1.3 do provide forward secrecy, the PFS priority string now
   only disables session tickets in TLS 1.2.  Future backward incompatibility:
   in the next major release of GnuTLS, we plan to remove those flag and
   modifier, and make GNUTLS_NO_TICKETS and %NO_TICKETS only affect TLS 1.2.

** gnutls-cli, gnutls-serv: Channel binding for printing information
   has been changed from tls-unique to tls-exporter as tls-unique is
   not supported in TLS 1.3.

** libgnutls: Certificate sanity checks has been enhanced to make
   gnutls more RFC 5280 compliant (!1583).
   Following changes were included:
   - critical extensions are parsed when loading x509
     certificate to prohibit any random octet strings.
     Requires strict-x509 configure option to be enabled
   - garbage bits in Key Usage extension are prohibited
   - empty DirectoryStrings in Distinguished name structures
     of Issuer and Subject name are prohibited

** libgnutls: Removed 3DES from FIPS approved algorithms (#1353).
   According to the section 2 of SP800-131A Rev.2, 3DES algorithm
   will be disallowed for encryption after December 31, 2023:
   https://csrc.nist.gov/publications/detail/sp/800-131a/rev-2/final

** libgnutls: Optimized support for AES-SIV-CMAC algorithms (#1217, #1312).
   The existing AEAD API that works in a scatter-gather fashion
   (gnutls_aead_cipher_encryptv2) has been extended to support AES-SIV-CMAC.
   For further optimization, new function (gnutls_aead_cipher_set_key) has been
   added to set key on the existing AEAD handle without re-allocation.

** libgnutls: HKDF and AES-GCM algorithms are now approved in FIPS-140 mode
   when used in TLS (#1311).

** The configure arguments for Brotli and Zstandard (zstd) support
   have changed to reflect the previous help text: they are now
   --with-brotli/--with-zstd respectively (#1342).

** Detecting the Zstandard (zstd) library in configure has been
   fixed (#1343).

** API and ABI modifications:
GNUTLS_NO_TICKETS_TLS12: New flag
gnutls_aead_cipher_set_key: New function

* Version 3.7.4 (released 2022-03-17)

** libgnutls: Added support for certificate compression as defined in RFC8879
   (#1301). New API functions (gnutls_compress_certificate_get_selected_method
   and gnutls_compress_certificate_set_methods) allow client and server to set
   their preferences.

** certtool: Added option --compress-cert that allows user to specify
   compression methods for certificate compression.

** libgnutls: GnuTLS can now be compiled with --enable-strict-x509 configure
   option to enforce stricter certificate sanity checks that are compliant with
   RFC5280.

** libgnutls: Removed IA5String type from DirectoryString within issuer
   and subject name to make DirectoryString RFC5280 compliant.

** libgnutls: Added function (gnutls_record_send_file) to send file content from
   open file descriptor (!1486). The implementation is optimized if KTLS (kernel
   TLS) is enabled.

** libgnutls: Added function (gnutls_ciphersuite_get) to retrieve the name of
   current ciphersuite from TLS session (#1291).

** libgnutls: The run-time dependency on tpm2-tss is now re-implemented using
   dlopen, so GnuTLS does not indirectly link to other crypto libraries until
   TPM2 functionality is utilized (!1544).

** API and ABI modifications:
GNUTLS_COMP_BROTLI: New gnutls_compression_method_t enum member
GNUTLS_COMP_ZSTD: New gnutls_compression_method_t enum member
gnutls_compress_certificate_get_selected_method: Added
gnutls_compress_certificate_set_methods: Added
gnutls_ciphersuite_get: New function
gnutls_record_send_file: New function
libgnutlsxx: Soname bumped due to ABI breakage introduced in 3.7.1

* Version 3.7.3 (released 2022-01-17)

** libgnutls: The allowlisting configuration mode has been added to the system-wide
   settings. In this mode, all the algorithms are initially marked as insecure
   or disabled, while the applications can re-enable them either through the
   [overrides] section of the configuration file or the new API (#1172).

** The build infrastructure no longer depends on GNU AutoGen for generating
   command-line option handling, template file parsing in certtool, and
   documentation generation (#773, #774). This change also removes run-time or
   bundled dependency on the libopts library, and requires Python 3.6 or later
   to regenerate the distribution tarball.

   Note that this brings in known backward incompatibility in command-line
   tools, such as long options are now case sensitive, while previously they
   were treated in a case insensitive manner: for example --RSA is no longer a
   valid option of certtool. The existing scripts using GnuTLS tools may need
   adjustment for this change.

** libgnutls: The tpm2-tss-engine compatible private blobs can be loaded and
   used as a gnutls_privkey_t (#594). The code was originally written for the
   OpenConnect VPN project by David Woodhouse. To generate such blobs, use the
   tpm2tss-genkey tool from tpm2-tss-engine:
   https://github.com/tpm2-software/tpm2-tss-engine/#rsa-operations
   or the tpm2_encodeobject tool from unreleased tpm2-tools.

** libgnutls: The library now transparently enables Linux KTLS
   (kernel TLS) when the feature is compiled in with --enable-ktls configuration
   option (#1113). If the KTLS initialization fails it automatically falls back
   to the user space implementation.

** certtool: The certtool command can now read the Certificate Transparency
   (RFC 6962) SCT extension (#232).  New API functions are also provided to
   access and manipulate the extension values.

** certtool: The certtool command can now generate, manipulate, and evaluate
   x25519 and x448 public keys, private keys, and certificates.

** libgnutls: Disabling a hashing algorithm through "insecure-hash"
   configuration directive now also disables TLS ciphersuites that use it as a
   PRF algorithm.

** libgnutls: PKCS#12 files are now created with modern algorithms by default
   (!1499).  Previously certtool used PKCS12-3DES-SHA1 for key derivation and
   HMAC-SHA1 as an integity measure in PKCS#12.  Now it uses AES-128-CBC with
   PBKDF2 and SHA-256 for both key derivation and MAC algorithms, and the
   default PBKDF2 iteration count has been increased to 600000.

** libgnutls: PKCS#12 keys derived using GOST algorithm now uses
   HMAC_GOSTR3411_2012_512 instead of HMAC_GOSTR3411_2012_256 for integrity, to
   conform with the latest TC-26 requirements (#1225).

** libgnutls: The library now provides a means to report the status of approved
   cryptographic operations (!1465). To adhere to the FIPS140-3 IG 2.4.C., this
   complements the existing mechanism to prohibit the use of unapproved
   algorithms by making the library unusable state.

** gnutls-cli: The gnutls-cli command now provides a --list-config option to
   print the library configuration (!1508).

** libgnutls: Fixed possible race condition in
   gnutls_x509_trust_list_verify_crt2 when a single trust list object is shared
   among multiple threads (#1277). [GNUTLS-SA-2022-01-17, CVSS: low]

** API and ABI modifications:
GNUTLS_PRIVKEY_FLAG_RSA_PSS_FIXED_SALT_LENGTH: new flag in gnutls_privkey_flags_t
GNUTLS_VERIFY_RSA_PSS_FIXED_SALT_LENGTH: new flag in gnutls_certificate_verify_flags
gnutls_ecc_curve_set_enabled: Added.
gnutls_sign_set_secure: Added.
gnutls_sign_set_secure_for_certs: Added.
gnutls_digest_set_secure: Added.
gnutls_protocol_set_enabled: Added.
gnutls_fips140_context_init: New function
gnutls_fips140_context_deinit: New function
gnutls_fips140_push_context: New function
gnutls_fips140_pop_context: New function
gnutls_fips140_get_operation_state: New function
gnutls_fips140_operation_state_t: New enum
gnutls_transport_is_ktls_enabled: New function
gnutls_get_library_configuration: New function

* Version 3.7.2 (released 2021-05-29)

** libgnutls: The priority string option %DISABLE_TLS13_COMPAT_MODE was added
   to disable TLS 1.3 middlebox compatibility mode

** libgnutls: The Linux kernel AF_ALG based acceleration has been added.
   This can be enabled with --enable-afalg configure option, when libkcapi
   package is installed (#308).

** libgnutls: Fixed timing of early data exchange. Previously, the client was
   sending early data after receiving Server Hello, which not only negates the
   benefit of 0-RTT, but also works under certain assumptions hold (e.g., the
   same ciphersuite is selected in initial and resumption handshake) (#1146).

** certtool: When signing a CSR, CRL distribution point (CDP) is no longer
   copied from the signing CA by default (#1126).

** libgnutls: The GNUTLS_NO_EXPLICIT_INIT envvar has been renamed to
   GNUTLS_NO_IMPLICIT_INIT to reflect the purpose (#1178). The former is now
   deprecated and will be removed in the future releases.

** certtool: When producing certificates and certificate requests, subject DN
   components that are provided individually will now be ordered by
   assumed scale (e.g. Country before State, Organization before
   OrganizationalUnit).  This change also affects the order in which
   certtool prompts interactively.  Please rely on the template
   mechanism for automated use of certtool! (#1243)

** API and ABI modifications:
gnutls_early_cipher_get: Added
gnutls_early_prf_hash_get: Added

** guile: Writes to a session record port no longer throw an exception upon
   GNUTLS_E_AGAIN or GNUTLS_E_INTERRUPTED.

* Version 3.7.1 (released 2021-03-10)

** libgnutls: Fixed potential use-after-free in sending "key_share"
   and "pre_shared_key" extensions. When sending those extensions, the
   client may dereference a pointer no longer valid after
   realloc. This happens only when the client sends a large Client
   Hello message, e.g., when HRR is sent in a resumed session
   previously negotiated large FFDHE parameters, because the initial
   allocation of the buffer is large enough without having to call
   realloc (#1151).  [GNUTLS-SA-2021-03-10, CVSS: low]

** libgnutls: Fixed a regression in handling duplicated certs in a
   chain (#1131).

** libgnutls: Fixed sending of session ID in TLS 1.3 middlebox
   compatibiltiy mode. In that mode the client shall always send a
   non-zero session ID to make the handshake resemble the TLS 1.2
   resumption; this was not true in the previous versions (#1074).

** libgnutls: W32 performance improvement with a new sendmsg()-like
   transport implementation (!1377).

** libgnutls: Removed dependency on the external 'fipscheck' package,
   when compiled with --enable-fips140-mode (#1101).

** libgnutls: Added padlock acceleration for AES-192-CBC (#1004).

** API and ABI modifications:
No changes since last version.

* Version 3.7.0 (released 2020-12-02)

** libgnutls: Depend on nettle 3.6 (!1322).

** libgnutls: Added a new API that provides a callback function to
   retrieve missing certificates from incomplete certificate chains
   (#202, #968, #1100).

** libgnutls: Added a new API that provides a callback function to
   output the complete path to the trusted root during certificate
   chain verification (#1012).

** libgnutls: OIDs exposed as gnutls_datum_t no longer account for the
   terminating null bytes, while the data field is null terminated.
   The affected API functions are: gnutls_ocsp_req_get_extension,
   gnutls_ocsp_resp_get_response, and gnutls_ocsp_resp_get_extension
   (#805).

** libgnutls: Added a new set of API to enable QUIC implementation (#826, #849,
   #850).

** libgnutls: The crypto implementation override APIs deprecated in 3.6.9 are
   now no-op (#790).

** libgnutls: Added MAGMA/KUZNYECHIK CTR-ACPKM and CMAC support (!1161).

** libgnutls: Support for padlock has been fixed to make it work with Zhaoxin
   CPU (#1079).

** libgnutls: The maximum PIN length for PKCS #11 has been increased from 31
   bytes to 255 bytes (#932).

** API and ABI modifications:
gnutls_x509_trust_list_set_getissuer_function: Added
gnutls_x509_trust_list_get_ptr: Added
gnutls_x509_trust_list_set_ptr: Added
gnutls_session_set_verify_output_function: Added
gnutls_record_encryption_level_t: New enum
gnutls_handshake_read_func: New callback type
gnutls_handshake_set_read_function: New function
gnutls_handshake_write: New function
gnutls_handshake_secret_func: New callback type
gnutls_handshake_set_secret_function: New function
gnutls_alert_read_func: New callback type
gnutls_alert_set_read_function: New function
gnutls_crypto_register_cipher: Deprecated; no-op
gnutls_crypto_register_aead_cipher: Deprecated; no-op
gnutls_crypto_register_mac: Deprecated; no-op
gnutls_crypto_register_digest: Deprecated; no-op

* Version 3.6.15 (releases 2020-09-04)

** libgnutls: Fixed "no_renegotiation" alert handling at incorrect timing.
   The server sending a "no_renegotiation" alert in an unexpected timing,
   followed by an invalid second handshake was able to cause a TLS 1.3 client to
   crash via a null-pointer dereference. The crash happens in the application's
   error handling path, where the gnutls_deinit function is called after
   detecting a handshake failure (#1071).  [GNUTLS-SA-2020-09-04, CVSS: medium]

** libgnutls: If FIPS self-tests are failed, gnutls_fips140_mode_enabled() now
   indicates that with a false return value (!1306).

** libgnutls: Under FIPS mode, the generated ECDH/DH public keys are checked
   accordingly to SP800-56A rev 3 (!1295, !1299).

** libgnutls: gnutls_x509_crt_export2() now returns 0 upon success, rather than
   the size of the internal base64 blob (#1025). The new behavior aligns to the
   existing documentation.

** libgnutls: Certificate verification failue due to OCSP must-stapling is not
   honered is now correctly marked with the GNUTLS_CERT_INVALID flag
   (!1317). The new behavior aligns to the existing documentation.

** libgnutls: The audit log message for weak hashes is no longer printed twice
   (!1301).

** libgnutls: Fixed version negotiation when TLS 1.3 is enabled and TLS 1.2 is
   disabled in the priority string. Previously, even when TLS 1.2 is explicitly
   disabled with "-VERS-TLS1.2", the server still offered TLS 1.2 if TLS 1.3 is
   enabled (#1054).

** API and ABI modifications:
No changes since last version.

* Version 3.6.14 (released 2020-06-03)

** libgnutls: Fixed insecure session ticket key construction, since 3.6.4.
   The TLS server would not bind the session ticket encryption key with a
   value supplied by the application until the initial key rotation, allowing
   attacker to bypass authentication in TLS 1.3 and recover previous
   conversations in TLS 1.2 (#1011).
   [GNUTLS-SA-2020-06-03, CVSS: high]

** libgnutls: Fixed handling of certificate chain with cross-signed
   intermediate CA certificates (#1008).

** libgnutls: Fixed reception of empty session ticket under TLS 1.2 (#997).

** libgnutls: gnutls_x509_crt_print() is enhanced to recognizes commonName
   (2.5.4.3), decodes certificate policy OIDs (!1245), and prints Authority
   Key Identifier (AKI) properly (#989, #991).

** certtool: PKCS #7 attributes are now printed with symbolic names (!1246).

** libgnutls: Added several improvements on Windows Vista and later releases
   (!1257, !1254, !1256). Most notably the system random number generator now
   uses Windows BCrypt* API if available (!1255).

** libgnutls: Use accelerated AES-XTS implementation if possible (!1244).
   Also both accelerated and non-accelerated implementations check key block
   according to FIPS-140-2 IG A.9 (!1233).

** libgnutls: Added support for AES-SIV ciphers (#463).

** libgnutls: Added support for 192-bit AES-GCM cipher (!1267).

** libgnutls: No longer use internal symbols exported from Nettle (!1235)

** API and ABI modifications:
GNUTLS_CIPHER_AES_128_SIV: Added
GNUTLS_CIPHER_AES_256_SIV: Added
GNUTLS_CIPHER_AES_192_GCM: Added
GNUTLS_NO_AUTO_SEND_TICKET: Added
gnutls_ext_get_name2: Added
gnutls_pkcs7_print_signature_info: Added

* Version 3.6.13 (released 2020-03-31)

** libgnutls: Fix a DTLS-protocol regression (caused by TLS1.3 support), since 3.6.3.
   The DTLS client would not contribute any randomness to the DTLS negotiation,
   breaking the security guarantees of the DTLS protocol (#960)
   [GNUTLS-SA-2020-03-31, CVSS: high]

** libgnutls: Added new APIs to access KDF algorithms (#813).

** libgnutls: Added new callback gnutls_keylog_func that enables a custom
   logging functionality.

** libgnutls: Added support for non-null terminated usernames in PSK
   negotiation (#586).

** gnutls-cli-debug: Improved support for old servers that only support
   SSL 3.0.

** API and ABI modifications:
gnutls_hkdf_extract: Added
gnutls_hkdf_expand: Added
gnutls_pbkdf2: Added
gnutls_session_get_keylog_function: Added
gnutls_session_set_keylog_function: Added
gnutls_prf_hash_get: Added
gnutls_psk_server_get_username2: Added
gnutls_psk_set_client_credentials2: Added
gnutls_psk_set_client_credentials_function2: Added
gnutls_psk_set_server_credentials_function2: Added


* Version 3.6.12 (released 2020-02-01)

** libgnutls: Introduced TLS session flag (gnutls_session_get_flags())
   to identify sessions that client request OCSP status request (#829).

** libgnutls: Added support for X448 key exchange (RFC 7748) and Ed448
   signature algorithm (RFC 8032) under TLS (#86).

** libgnutls: Added the default-priority-string option to system configuration;
   it allows overriding the compiled-in default-priority-string.

** libgnutls: Added support for GOST CNT_IMIT ciphersuite (as defined by
   draft-smyshlyaev-tls12-gost-suites-07).
   By default this ciphersuite is disabled. It can be enabled by adding
   +GOST to priority string. In the future this priority string may enable
   other GOST ciphersuites as well.  Note, that server will fail to negotiate
   GOST ciphersuites if TLS 1.3 is enabled both on a server and a client. It
   is recommended for now to disable TLS 1.3 in setups where GOST ciphersuites
   are enabled on GnuTLS-based servers.

** libgnutls: added priority shortcuts for different GOST categories like
   CIPHER-GOST-ALL, MAC-GOST-ALL, KX-GOST-ALL, SIGN-GOST-ALL, GROUP-GOST-ALL.

** libgnutls: Reject certificates with invalid time fields. That is we reject
   certificates with invalid characters in Time fields, or invalid time formatting
   To continue accepting the invalid form compile with --disable-strict-der-time
   (#207, #870).

** libgnutls: Reject certificates which contain duplicate extensions. We were
   previously printing warnings when printing such a certificate, but that is
   not always sufficient to flag such certificates as invalid. Instead we now
   refuse to import them (#887).

** libgnutls: If a CA is found in the trusted list, check in addition to
   time validity, whether the algorithms comply to the expected level prior
   to accepting it. This addresses the problem of accepting CAs which would
   have been marked as insecure otherwise (#877).

** libgnutls: The min-verification-profile from system configuration applies
   for all certificate verifications, not only under TLS. The configuration can
   be overriden using the GNUTLS_SYSTEM_PRIORITY_FILE environment variable.

** libgnutls: The stapled OCSP certificate verification adheres to the convention
   used throughout the library of setting the 'GNUTLS_CERT_INVALID' flag.

** libgnutls: On client side only send OCSP staples if they have been requested
   by the server, and on server side always advertise that we support OCSP stapling
   (#876).

** libgnutls: Introduced the gnutls_ocsp_req_const_t which is compatible
   with gnutls_ocsp_req_t but const.

** certtool: Added the --verify-profile option to set a certificate
   verification profile. Use '--verify-profile low' for certificate verification
   to apply the 'NORMAL' verification profile.

** certtool: The add_extension template option is considered even when generating
   a certificate from a certificate request.

** API and ABI modifications:
GNUTLS_SFLAGS_CLI_REQUESTED_OCSP: Added
GNUTLS_SFLAGS_SERV_REQUESTED_OCSP: Added
gnutls_ocsp_req_const_t: Added


* Version 3.6.11 (released 2019-12-01)

** libgnutls: Use KERN_ARND for the system random number generator on NetBSD.
   This syscall provides an endless stream of random numbers from the kernel's
   ChaCha20-based random number generator, without blocking or requiring an open file
   descriptor.

** libgnutls: Corrected issue with TLS 1.2 session ticket handling as client
   during resumption (#841).

** libgnutls: gnutls_base64_decode2() succeeds decoding the empty string to
   the empty string. This is a behavioral change of the API but it conforms
   to the RFC4648 expectations (#834).

** libgnutls: Fixed AES-CFB8 implementation, when input is shorter than
   the block size. Fix backported from nettle.

** certtool: CRL distribution points will be set in CA certificates even when
   non self-signed (#765).

** gnutls-cli/serv: added raw public-key handling capabilities (RFC7250).
   Key material can be set via the --rawpkkeyfile and --rawpkfile flags.

** API and ABI modifications:
No changes since last version.


* Version 3.6.10 (released 2019-09-29)

** libgnutls: Added support for deterministic ECDSA/DSA (RFC6979)
   Deterministic signing can be enabled by setting
   GNUTLS_PRIVKEY_FLAG_REPRODUCIBLE when calling gnutls_privkey_sign_*()
   functions (#94).

** libgnutls: add gnutls_aead_cipher_encryptv2 and gnutls_aead_cipher_decryptv2
   functions that will perform in-place encryption/decryption on data buffers (#718).

** libgnutls: Corrected issue in gnutls_session_get_data2() which could fail under
   TLS1.3, if a timeout callback was not set using gnutls_transport_set_pull_timeout_function()
   (#823).

** libgnutls: added interoperability tests with gnutls 2.12.x; addressed
   issue with large record handling due to random padding (#811).

** libgnutls: the server now selects the highest TLS protocol version,
   if TLS 1.3 is enabled and the client advertises an older protocol version first (#837).

** libgnutls: fix non-PIC assembly on i386 (#818).

** libgnutls: added support for GOST 28147-89 cipher in CNT (GOST counter) mode
   and MAC generation based on GOST 28147-89 (IMIT). For description of the
   modes see RFC 5830. S-Box is id-tc26-gost-28147-param-Z (TC26Z) defined in
   RFC 7836.

** certtool: when outputting an encrypted private key do not insert the textual description
   of it. This fixes a regression since 3.6.5 (#840).

** API and ABI modifications:
gnutls_aead_cipher_encryptv2: Added
gnutls_aead_cipher_decryptv2: Added
GNUTLS_CIPHER_GOST28147_TC26Z_CNT: Added
GNUTLS_MAC_GOST28147_TC26Z_IMIT: Added

* Version 3.6.9 (released 2019-07-25)

** libgnutls: add gnutls_hash_copy/gnutls_hmac_copy functions that will create a copy
   of digest or MAC context. Copying contexts for externally-registered digest and MAC
   contexts is unupported (#787).

** Marked the crypto implementation override APIs as deprecated. These APIs are rarely
   used, are for a niche use case, but have significant side effects, such as preventing
   any internal re-organization and extension of the internal cipher API. The APIs remain
   functional though a compiler warning will be issued, and a future minor version update
   may transform them to a no-op while keeping ABI compatibility (#789).

** libgnutls: Added support for AES-GMAC, as a separate to GCM, MAC algorithm (#781).

** libgnutls: gnutls_privkey_sign_hash2 now accepts the GNUTLS_PRIVKEY_SIGN_FLAG_TLS1_RSA
   flag as documented. This makes it a complete replacement of gnutls_privkey_sign_hash().

** libgnutls: Added support for Generalname registeredID.

** The priority configuration was enhanced to allow more elaborate
   system-wide configuration of the library (#587).
   The following changes were included:
    - The file is read as an ini file with '#' indicating a comment.
    - The section "[priorities]" or global follows the existing semantics of
      the configuration file, and allows to specify system-wide priority strings
      which are accessed with the '@' prefix.
    - The section "[overrides]" is added with the parameters "insecure-hash",
      "insecure-sig", "insecure-sig-for-cert", "disabled-curve",
      "disabled-version", "min-verification-profile", "tls-disabled-cipher",
      "tls-disabled-mac", "tls-disabled-group", "tls-disabled-kx", which prohibit
      specific algorithms or options globally. Existing algorithms in the
      library can be marked as disabled and insecure, but no hard-coded
      insecure algorithm can be marked as secure (so that the configuration
      cannot be abused to make the system vulnerable).
    - Unknown sections or options are skipped with a debug message, unless
      the GNUTLS_SYSTEM_PRIORITY_FAIL_ON_INVALID environment parameter is
      set to 1.

** libgnutls: Added new flag for GNUTLS_CPUID_OVERRIDE
    - 0x20: Enable SHA_NI instruction set

** API and ABI modifications:
gnutls_crypto_register_cipher: Deprecated
gnutls_crypto_register_aead_cipher: Deprecated
gnutls_crypto_register_digest: Deprecated
gnutls_crypto_register_mac: Deprecated
gnutls_get_system_config_file: Added
gnutls_hash_copy: Added
gnutls_hmac_copy: Added
GNUTLS_MAC_AES_GMAC_128: Added
GNUTLS_MAC_AES_GMAC_192: Added
GNUTLS_MAC_AES_CMAC_256: Added
GNUTLS_SAN_REGISTERED_ID: Added


* Version 3.6.8 (released 2019-05-28)

** libgnutls: Added gnutls_prf_early() function to retrieve early keying
   material (#329)

** libgnutls: Added support for AES-XTS cipher (#354)

** libgnutls: Fix calculation of Streebog digests (incorrect carry operation in
   512 bit addition)

** libgnutls: During Diffie-Hellman operations in TLS, verify that the peer's
   public key is on the right subgroup (y^q=1 mod p), when q is available (under
   TLS 1.3 and under earlier versions when RFC7919 parameters are used).

** libgnutls: the gnutls_srp_set_server_credentials_function can now be used
   with the 8192 parameters as well (#995).

** libgnutls: Fixed bug preventing the use of gnutls_pubkey_verify_data2() and
   gnutls_pubkey_verify_hash2() with the GNUTLS_VERIFY_DISABLE_CA_SIGN flag (#754)

** libgnutls: The priority string option %ALLOW_SMALL_RECORDS was added to allow
   clients to communicate with the server advertising smaller limits than 512

** libgnutls: Apply STD3 ASCII rules in gnutls_idna_map() to prevent
   hostname/domain crafting via IDNA conversion (#720)

** certtool: allow the digital signature key usage flag in CA certificates.
   Previously certtool would ignore this flag for CA certificates even if
   specified (#767)

** gnutls-cli/serv: added the --keymatexport and --keymatexportsize options.
   These allow testing the RFC5705 using these tools.

** API and ABI modifications:
gnutls_prf_early: Added
gnutls_record_set_max_recv_size: Added
gnutls_dh_params_import_raw3: Added
gnutls_ffdhe_2048_group_q: Added
gnutls_ffdhe_3072_group_q: Added
gnutls_ffdhe_4096_group_q: Added
gnutls_ffdhe_6144_group_q: Added
gnutls_ffdhe_8192_group_q: Added


* Version 3.6.7 (released 2019-03-27)

** libgnutls, gnutls tools: Every gnutls_free() will automatically set
   the free'd pointer to NULL. This prevents possible use-after-free and
   double free issues. Use-after-free will be turned into NULL dereference.
   The counter-measure does not extend to applications using gnutls_free().

** libgnutls: Fixed a memory corruption (double free) vulnerability in the
   certificate verification API. Reported by Tavis Ormandy; addressed with
   the change above. [GNUTLS-SA-2019-03-27, #694]

** libgnutls: Fixed an invalid pointer access via malformed TLS1.3 async messages;
   Found using tlsfuzzer. [GNUTLS-SA-2019-03-27, #704]

** libgnutls: enforce key usage limitations on certificates more actively.
   Previously we would enforce it for TLS1.2 protocol, now we enforce it
   even when TLS1.3 is negotiated, or on client certificates as well. When
   an inappropriate for TLS1.3 certificate is seen on the credentials structure
   GnuTLS will disable TLS1.3 support for that session (#690).

** libgnutls: the default number of tickets sent under TLS 1.3 was increased to
   two. This makes it easier for clients which perform multiple connections
   to the server to use the tickets sent by a default server.

** libgnutls: enforce the equality of the two signature parameters fields in
   a certificate. We were already enforcing the signature algorithm, but there
   was a bug in parameter checking code.

** libgnutls: fixed issue preventing sending and receiving from different
   threads when false start was enabled (#713).

** libgnutls: the flag GNUTLS_PKCS11_OBJ_FLAG_LOGIN_SO now implies a writable
   session, as non-writeable security officer sessions are undefined in PKCS#11
   (#721).

** libgnutls: no longer send downgrade sentinel in TLS 1.3.
   Previously the sentinel value was embedded to early in version
   negotiation and was sent even on TLS 1.3. It is now sent only when
   TLS 1.2 or earlier is negotiated (#689).

** gnutls-cli: Added option --logfile to redirect informational messages output.

** API and ABI modifications:
No changes since last version.


* Version 3.6.6 (released 2019-01-25)

** libgnutls: gnutls_pubkey_import_ecc_raw() was fixed to set the number bits
   on the public key (#640).

** libgnutls: Added support for raw public-key authentication as defined in RFC7250.
   Raw public-keys can be negotiated by enabling the corresponding certificate
   types via the priority strings. The raw public-key mechanism must be explicitly
   enabled via the GNUTLS_ENABLE_RAWPK init flag (#26, #280).

** libgnutls: When on server or client side we are sending no extensions we do
   not set an empty extensions field but we rather remove that field competely.
   This solves a regression since 3.5.x and improves compatibility of the server
   side with certain clients.

** libgnutls: We no longer mark RSA keys in PKCS#11 tokens as RSA-PSS capable if
   the CKA_SIGN is not set (#667).

** libgnutls: The priority string option %NO_EXTENSIONS was improved to completely
   disable extensions at all cases, while providing a functional session. This
   also implies that when specified, TLS1.3 is disabled.

** libgnutls: GNUTLS_X509_NO_WELL_DEFINED_EXPIRATION was marked as deprecated.
   The previous definition was non-functional (#609).

** API and ABI modifications:
GNUTLS_ENABLE_RAWPK: Added
GNUTLS_ENABLE_CERT_TYPE_NEG: Removed (was no-op; replaced by GNUTLS_ENABLE_RAWPK) 
GNUTLS_X509_NO_WELL_DEFINED_EXPIRATION: Deprecated
GNUTLS_PCERT_NO_CERT: Deprecated


* Version 3.6.5 (released 2018-12-01)

** libgnutls: Provide the option of transparent re-handshake/reauthentication
   when the GNUTLS_AUTO_REAUTH flag is specified in gnutls_init() (#571).

** libgnutls: Added support for TLS 1.3 zero round-trip (0-RTT) mode (#127)

** libgnutls: The priority functions will ignore and not enable TLS1.3 if
   requested with legacy TLS versions enabled but not TLS1.2. That is because
   if such a priority string is used in the client side (e.g., TLS1.3+TLS1.0 enabled)
   servers which do not support TLS1.3 will negotiate TLS1.2 which will be
   rejected by the client as disabled (#621).

** libgnutls: Change RSA decryption to use a new side-channel silent function.
   This addresses a security issue where memory access patterns as well as timing
   on the underlying Nettle rsa-decrypt function could lead to new Bleichenbacher
   attacks. Side-channel resistant code is slower due to the need to mask
   access and timings. When used in TLS the new functions cause RSA based
   handshakes to be between 13% and 28% slower on average (Numbers are indicative,
   the tests where performed on a relatively modern Intel CPU, results vary
   depending on the CPU and architecture used). This change makes nettle 3.4.1
   the minimum requirement of gnutls (#630). [CVSS: medium]

** libgnutls: gnutls_priority_init() and friends, allow the CTYPE-OPENPGP keyword
   in the priority string. It is only accepted as legacy option and is ignored.

** libgnutls: Added support for EdDSA under PKCS#11 (#417)

** libgnutls: Added support for AES-CFB8 cipher (#357)

** libgnutls: Added support for AES-CMAC MAC (#351)

** libgnutls: In two previous versions GNUTLS_CIPHER_GOST28147_CPB/CPC/CPD_CFB ciphers
   have incorrectly used CryptoPro-A S-BOX instead of proper (CryptoPro-B/-C/-D
   S-BOXes). They are fixed now.

** libgnutls: Added support for GOST key unmasking and unwrapped GOST private
   keys parsing, as specified in R 50.1.112-2016.

** gnutls-serv: It applies the default settings when no --priority option is given,
   using gnutls_set_default_priority().

** p11tool: Fix initialization of security officer's PIN with the --initialize-so-pin
   option (#561)

** certtool: Add parameter --no-text that prevents certtool from outputting
   text before PEM-encoded private key, public key, certificate, CRL or CSR.

** API and ABI modifications:
GNUTLS_AUTO_REAUTH: Added
GNUTLS_CIPHER_AES_128_CFB8: Added
GNUTLS_CIPHER_AES_192_CFB8: Added
GNUTLS_CIPHER_AES_256_CFB8: Added
GNUTLS_MAC_AES_CMAC_128: Added
GNUTLS_MAC_AES_CMAC_256: Added
gnutls_record_get_max_early_data_size: Added
gnutls_record_send_early_data: Added
gnutls_record_recv_early_data: Added
gnutls_db_check_entry_expire_time: Added
gnutls_anti_replay_set_add_function: Added
gnutls_anti_replay_init: Added
gnutls_anti_replay_deinit: Added
gnutls_anti_replay_set_window: Added
gnutls_anti_replay_enable: Added
gnutls_privkey_decrypt_data2: Added


* Version 3.6.4 (released 2018-09-24)

** libgnutls: Added the final (RFC8446) version numbering of the TLS1.3 protocol.

** libgnutls: Corrected regression since 3.6.3 in the callbacks set with
   gnutls_certificate_set_retrieve_function() which could not handle the case where
   no certificates were returned, or the callbacks were set to NULL (see #528).

** libgnutls: gnutls_handshake() on server returns early on handshake when no
   certificate is presented by client and the gnutls_init() flag GNUTLS_ENABLE_EARLY_START
   is specified.

** libgnutls: Added session ticket key rotation on server side with TOTP.
   The key set with gnutls_session_ticket_enable_server() is used as a
   master key to generate time-based keys for tickets. The rotation
   relates to the gnutls_db_set_cache_expiration() period.

** libgnutls: The 'record size limit' extension is added and preferred to the
   'max record size' extension when possible.

** libgnutls: Provide a more flexible PKCS#11 search of trust store certificates.
   This addresses the problem where the CA certificate doesn't have a subject key
   identifier whereas the end certificates have an authority key identifier (#569)

** libgnutls: gnutls_privkey_export_gost_raw2(), gnutls_privkey_import_gost_raw(),
   gnutls_pubkey_export_gost_raw2(), gnutls_pubkey_import_gost_raw() import
   and export GOST parameters in the "native" little endian format used for these
   curves. This is an intentional incompatible change with 3.6.3.

** libgnutls: Added support for seperately negotiating client and server certificate types
   as defined in RFC7250. This mechanism must be explicitly enabled via the
   GNUTLS_ENABLE_CERT_TYPE_NEG flag in gnutls_init().

** gnutls-cli: enable CRL validation on startup (#564)

** API and ABI modifications:
GNUTLS_ENABLE_EARLY_START: Added
GNUTLS_ENABLE_CERT_TYPE_NEG: Added
GNUTLS_TL_FAIL_ON_INVALID_CRL: Added
GNUTLS_CERTIFICATE_VERIFY_CRLS: Added
gnutls_ctype_target_t: New enumeration
gnutls_record_set_max_early_data_size: Added
gnutls_certificate_type_get2: Added
gnutls_priority_certificate_type_list2: Added
gnutls_ffdhe_6144_group_prime: Added
gnutls_ffdhe_6144_group_generator: Added
gnutls_ffdhe_6144_key_bits: Added


* Version 3.6.3 (released 2018-07-16)

** libgnutls: Introduced support for draft-ietf-tls-tls13-28. It includes version
   negotiation, post handshake authentication, length hiding, multiple OCSP support,
   consistent ciphersuite support across protocols, hello retry requests, ability
   to adjust key shares via gnutls_init() flags, certificate authorities extension,
   and key usage limits. TLS1.3 draft-28 support can be enabled by default if
   the option --enable-tls13-support is given to configure script.

** libgnutls: Apply compatibility settings for existing applications running with TLS1.2 or
   earlier and TLS 1.3. When SRP or NULL ciphersuites are specified in priority strings
   TLS 1.3 is will be disabled. When Anonymous ciphersuites are specified in priority
   strings, then TLS 1.3 negotiation will be disabled if the session is associated
   only with an anonymous credentials structure.

** Added support for Russian Public Key Infrastructure according to RFCs 4491/4357/7836.
   This adds support for using GOST keys for digital signatures and under PKCS#7, PKCS#12,
   and PKCS#8 standards. In particular added elliptic curves GOST R 34.10-2001 CryptoProA
   256-bit curve (RFC 4357), GOST R 34.10-2001 CryptoProXchA 256-bit curve (RFC 4357),
   and GOST R 34.10-2012 TC26-512-A 512-bit curve (RFC 7836).

** Provide a uniform cipher list across supported TLS protocols; the CAMELLIA ciphers
   as well as ciphers utilizing HMAC-SHA384 and SHA256 have been removed from the default
   priority strings, as they are undefined under TLS1.3 and they provide no advantage
   over other options in earlier protocols.

** The SSL 3.0 protocol is disabled on compile-time by default. It can be re-enabled
   by specifying --enable-ssl3-support on configure script.

** libgnutls: Introduced function to switch the current FIPS140-2 operational
   mode, i.e., strict vs a more lax mode which will allow certain non FIPS140-2
   operations.

** libgnutls: Introduced low-level function to assist applications attempting client
   hello extension parsing, prior to GnuTLS' parsing of the message.

** libgnutls: When exporting an X.509 certificate avoid re-encoding if there are no
   modifications to the certificate. That prevents DER re-encoding issues with incorrectly
   encoded certificates, or other DER incompatibilities to affect a TLS session.
   Relates with #403

** libgnutls: on group exchange honor the %SERVER_PRECEDENCE and select the groups
   which are preferred by the server. That unfortunately has complicated semantics
   as TLS1.2 requires specific ordering of the groups based on the ciphersuite ordering,
   which could make group order unpredictable if TLS1.3 is negotiated.

** Improved counter-measures for TLS CBC record padding. Kenny Paterson, Eyal Ronen
   and Adi Shamir reported that the existing counter-measures had certain issues and
   were insufficient when the attacker has additional access to the CPU cache and
   performs a chosen-plaintext attack. This affected the legacy CBC ciphersuites. [CVSS: medium]

** Introduced the %FORCE_ETM priority string option. This option prevents the negotiation
   of legacy CBC ciphersuites unless encrypt-then-mac is negotiated.

** libgnutls: gnutls_privkey_import_ext4() was enhanced with the
   GNUTLS_PRIVKEY_INFO_PK_ALGO_BITS flag.

** libgnutls: gnutls_pkcs11_copy_secret_key, gnutls_pkcs11_copy_x509_privkey2,
   gnutls_pkcs11_privkey_generate3 will mark objects as sensitive by default
   unless GNUTLS_PKCS11_OBJ_FLAG_MARK_NOT_SENSITIVE is specified. This is an API
   change for these functions which make them err towards safety.

** libgnutls: improved aarch64 cpu features detection by using getauxval().

** certtool: It is now possible to specify certificate and serial CRL numbers greater
   than 2**63-2 as a hex-encoded string both when prompted and in a template file.
   Default certificate serial numbers are now fully random. Default CRL
   numbers include more random bits and are larger than in previous GnuTLS versions.
   Since CRL numbers are required to be monotonic, specify suitable CRL numbers manually
   if you intend to later downgrade to previous versions as it was not possible
   to specify large CRL numbers in previous versions of certtool.

** API and ABI modifications:
gnutls_fips140_set_mode: Added
gnutls_session_key_update: Added
gnutls_ext_get_current_msg: Added
gnutls_reauth: Added
gnutls_ocsp_status_request_get2: Added
gnutls_ocsp_resp_import2: Added
gnutls_ocsp_resp_export2: Added
gnutls_ocsp_resp_list_import2: Added
gnutls_certificate_set_retrieve_function3: Added
gnutls_certificate_set_ocsp_status_request_file2: Added
gnutls_certificate_set_ocsp_status_request_mem: Added
gnutls_certificate_get_ocsp_expiration: Added
gnutls_record_send2: Added
gnutls_ext_raw_parse: Added
gnutls_x509_crt_list_import_url: Added
gnutls_pcert_list_import_x509_file: Added