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 3.8.10 (released 2025-07-08)

** libgnutls: Fix NULL pointer dereference when 2nd Client Hello omits PSK
   Reported by Stefan Bühler. [GNUTLS-SA-2025-07-07-4, CVSS: medium]
   [CVE-2025-6395]

** libgnutls: Fix heap read buffer overrun in parsing X.509 SCTS timestamps
   Spotted by oss-fuzz and reported by OpenAI Security Research Team,
   and fix developed by Andrew Hamilton. [GNUTLS-SA-2025-07-07-1,
   CVSS: medium] [CVE-2025-32989]

** libgnutls: Fix double-free upon error when exporting otherName in SAN
   Reported by OpenAI Security Research Team. [GNUTLS-SA-2025-07-07-2,
   CVSS: low] [CVE-2025-32988]

** certtool: Fix 1-byte write buffer overrun when parsing template
   Reported by David Aitel. [GNUTLS-SA-2025-07-07-3,
   CVSS: low] [CVE-2025-32990]

** libgnutls: PKCS#11 modules can now be used to override the default
   cryptographic backend. Use the [provider] section in the system-wide config
   to specify path and pin to the module (see system-wide config Documentation).

** libgnutls: Linux kernel version 6.14 brings a Kernel TLS (kTLS) key update
   support. The library running on the aforementioned version now utilizes the
   kernel’s key update mechanism when kTLS is enabled, allowing uninterrupted
   TLS session. The --enable-ktls configure option as well as the system-wide
   kTLS configuration(see GnuTLS Documentation) are still required to enable
   this feature.

** libgnutls: liboqs support for PQC has been removed
   For maintenance purposes, support for post-quantum cryptography
   (PQC) is now only provided through leancrypto. The experimental key
   exchange algorithm, X25519Kyber768Draft00, which is based on the
   round 3 candidate of Kyber and only supported through liboqs has
   also been removed altogether.

** libgnutls: TLS certificate compression methods can now be set with
   cert-compression-alg configuration option in the gnutls priority file.

** libgnutls: All variants of ML-DSA private key formats are supported
   While the previous implementation of ML-DSA was based on
   draft-ietf-lamps-dilithium-certificates-04, this updates it to
   draft-ietf-lamps-dilithium-certificates-12 with support for all 3
   variants of private key formats: "seed", "expandedKey", and "both".

** libgnutls: ML-DSA signatures can now be used in TLS
   The ML-DSA signature algorithms, ML-DSA-44, ML-DSA-65, and
   ML-DSA-87, can now be used to digitally sign TLS handshake
   messages.

** API and ABI modifications:
GNUTLS_PKCS_MLDSA_SEED: New enum member of gnutls_pkcs_encrypt_flags_t
GNUTLS_PKCS_MLDSA_EXPANDED: New enum member of gnutls_pkcs_encrypt_flags_t

* Version 3.8.9 (released 2025-02-07)

** libgnutls: leancrypto was added as an interim option for PQC
   The library can now be built with leancrypto instead of liboqs for
   post-quantum cryptography (PQC), when configured with
   --with-leancrypto option instead of --with-liboqs.

** libgnutls: Experimental support for ML-DSA signature algorithm
   The library and certtool now support ML-DSA signature algorithm as
   defined in FIPS 204 and based on
   draft-ietf-lamps-dilithium-certificates-04. This feature is
   currently marked as experimental and can only be enabled when
   compiled with --with-leancrypto or --with-liboqs.
   Contributed by David Dudas.

** libgnutls: Support for ML-KEM-1024 key encapsulation mechanism
   The support for ML-KEM post-quantum key encapsulation mechanisms
   has been extended to cover ML-KEM-1024, in addition to ML-KEM-768.
   MLKEM1024 is only offered as SecP384r1MLKEM1024 hybrid as per
   draft-kwiatkowski-tls-ecdhe-mlkem-03.

** libgnutls: Fix potential DoS in handling certificates with numerous name
   constraints, as a follow-up of CVE-2024-12133 in libtasn1. The
   bundled copy of libtasn1 has also been updated to the latest 4.20.0
   release to complete the fix.  Reported by Bing Shi (#1553).
   [GNUTLS-SA-2025-02-07, CVSS: medium] [CVE-2024-12243]

** API and ABI modifications:
GNUTLS_PK_MLDSA44: New enum member of gnutls_pk_algorithm_t
GNUTLS_PK_MLDSA65: New enum member of gnutls_pk_algorithm_t
GNUTLS_PK_MLDSA87: New enum member of gnutls_pk_algorithm_t
GNUTLS_SIGN_MLDSA44: New enum member of gnutls_sign_algorithm_t
GNUTLS_SIGN_MLDSA65: New enum member of gnutls_sign_algorithm_t
GNUTLS_SIGN_MLDSA87: New enum member of gnutls_sign_algorithm_t

* Version 3.8.8 (released 2024-11-05)

** libgnutls: Experimental support for X25519MLKEM768 and SecP256r1MLKEM768 key exchange in TLS 1.3
   The support for post-quantum key exchanges has been extended to
   cover the final standard of ML-KEM, following
   draft-kwiatkowski-tls-ecdhe-mlkem. The minimum supported version of
   liboqs is bumped to 0.11.0.

** libgnutls: All records included in an OCSP response are now checked in TLS
   Previously, when multiple records are provided in a single OCSP
   response, only the first record was considered; now all those
   records are examined until the server certificate matches.

** libgnutls: Handling of malformed compress_certificate extension is now more standard compliant
   The server behavior of receiving a malformed compress_certificate
   extension now more strictly follows RFC 8879; return
   illegal_parameter alert instead of bad_certificate, as well as
   overlong extension data is properly rejected.

** build: More flexible library linking options for compression libraries, TPM, and liboqs support
   The configure options, --with-zstd, --with-brotli, --with-zlib,
   --with-tpm2, and --with-liboqs now take 4 states:
   yes/link/dlopen/no, to specify how the libraries are linked or
   loaded.

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

* Version 3.8.7 (released 2024-08-15)

** libgnutls: New configure option to compile out DSA support
   The --disable-dsa configure option has been added to completely disable DSA
   algorithm support.

** libgnutls: Experimental support for X25519Kyber768Draft00 key exchange in TLS
   For testing purposes, the hybrid post-quantum key exchange defined
   in draft-tls-westerbaan-xyber768d00 has been implemented using
   liboqs. Since the algorithm is still not finalized, the support of
   this key exchange is disabled by default and can be enabled with
   the --with-liboqs configure option.

** API and ABI modifications:
GNUTLS_PK_MLKEM768: New enum member of gnutls_pk_algorithm_t

* Version 3.8.6 (released 2024-07-03)

** libgnutls: PBMAC1 is now supported as a MAC mechanism for PKCS#12
   To be compliant with FIPS 140-3, PKCS#12 files with MAC based on
   PBKDF2 (PBMAC1) is now supported, according to the specification
   proposed in draft-ietf-lamps-pkcs12-pbmac1.

** libgnutls: SHA3 extendable output functions (XOF) are now supported
   SHA3 XOF, SHAKE128 and SHAKE256, are now usable through a new
   public API gnutls_hash_squeeze.

** API and ABI modifications:
gnutls_pkcs12_generate_mac3: New function
gnutls_pkcs12_flags_t: New enum
gnutls_hash_squeeze: New function

* Version 3.8.5 (released 2024-04-04)

** libgnutls: Due to majority of usages and implementations of
   RSA decryption with PKCS#1 v1.5 padding being incorrect,
   leaving them vulnerable to Marvin attack, the RSAES-PKCS1-v1_5
   is being deprecated (encryption and decryption) and will be
   disabled in the future. A new option `allow-rsa-pkcs1-encrypt`
   has been added into the system-wide library configuration which
   allows to enable/disable the RSAES-PKCS1-v1_5. Currently, the
   RSAES-PKCS1-v1_5 is enabled by default.

** libgnutls: Added support for RIPEMD160 and PBES1-DES-SHA1 for
   backward compatibility with GCR.

** libgnutls: A couple of memory related issues have been fixed in RSA PKCS#1
   v1.5 decryption error handling and deterministic ECDSA with earlier
   versions of GMP.  These were a regression introduced in the 3.8.4
   release. See #1535 and !1827.

** build: Fixed a bug where building gnutls statically failed due
   to a duplicate definition of nettle_rsa_compute_root_tr().

** API and ABI modifications:
GNUTLS_PKCS_PBES1_DES_SHA1: New enum member of gnutls_pkcs_encrypt_flags_t

* Version 3.8.4 (released 2024-03-18)

** libgnutls: RSA-OAEP encryption scheme is now supported
   To use it with an unrestricted RSA private key, one would need to
   initialize a gnutls_x509_spki_t object with necessary parameters
   for RSA-OAEP and attach it to the private key. It is also possible
   to import restricted private keys if they are stored in PKCS#8
   format.

** libgnutls: Fix side-channel in the deterministic ECDSA.
   Reported by George Pantelakis (#1516).
   [GNUTLS-SA-2023-12-04, CVSS: medium] [CVE-2024-28834]

** libgnutls: Fixed a bug where certtool crashed when verifying a certificate
   chain with more than 16 certificates. Reported by William Woodruff (#1525)
   and yixiangzhike (#1527).
   [GNUTLS-SA-2024-01-23, CVSS: medium] [CVE-2024-28835]

** libgnutls: Compression libraries are now loaded dynamically as needed
   instead of all being loaded during gnutls library initialization.
   As a result, the library initialization should be faster.

** build: The gnutls library can now be linked with the static library
   of GMP.  Note that in order for this to work libgmp.a needs to be
   compiled with -fPIC and libhogweed in Nettle also has to be linked
   to the static library of GMP.  This can be used to prevent custom
   memory allocators from being overriden by other applications.

** API and ABI modifications:
gnutls_x509_spki_get_rsa_oaep_params: New function.
gnutls_x509_spki_set_rsa_oaep_params: New function.
GNUTLS_PK_RSA_OAEP: New enum member of gnutls_pk_algorithm_t.

* Version 3.8.3 (released 2024-01-16)

** libgnutls: Fix more timing side-channel inside RSA-PSK key exchange
   [GNUTLS-SA-2024-01-14, CVSS: medium] [CVE-2024-0553]

** libgnutls: Fix assertion failure when verifying a certificate chain with a
   cycle of cross signatures
   [GNUTLS-SA-2024-01-09, CVSS: medium] [CVE-2024-0567]

** libgnutls: Fix regression in handling Ed25519 keys stored in PKCS#11 token
   certtool was unable to handle Ed25519 keys generated on PKCS#11
   with pkcs11-tool (OpenSC). This is a regression introduced in 3.8.2.

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

* Version 3.8.2 (released 2023-11-14)

** libgnutls: Fix timing side-channel inside RSA-PSK key exchange.
   [GNUTLS-SA-2023-10-23, CVSS: medium] [CVE-2023-5981]

** libgnutls: Add API functions to perform ECDH and DH key agreement
   The functionality has been there for a long time though they were
   not available as part of the public API.  This enables applications
   to implement custom protocols leveraging non-interactive key
   agreement with ECDH and DH.

** libgnutls: Added support for AES-GCM-SIV ciphers (RFC 8452)
   The new algorithms GNUTLS_CIPHER_AES_128_SIV_GCM and
   GNUTLS_CIPHER_AES_256_SIV_GCM have been added to be used through
   the AEAD interface.  Note that, unlike
   GNUTLS_CIPHER_AES_{128,256}_SIV_GCM, the authentication tag is
   appended to the ciphertext, not prepended.

** libgnutls: transparent KTLS support is extended to FreeBSD kernel
   The kernel TLS feature can now be enabled on FreeBSD as well as
   Linux when compiled with the --enable-ktls configure option.

** gnutls-cli: New option --starttls-name
   Depending on deployment, application protocols such as XMPP may
   require a different origin address than the external address to be
   presented prior to STARTTLS negotiation.  The --starttls-name can
   be used to specify specify the addresses separately.

** API and ABI modifications:
gnutls_pubkey_import_dh_raw: New function
gnutls_privkey_import_dh_raw: New function
gnutls_pubkey_export_dh_raw: New function
gnutls_privkey_export_dh_raw: New function
gnutls_x509_privkey_import_dh_raw: New function
gnutls_privkey_derive_secret: New function
GNUTLS_KEYGEN_DH: New enum member of gnutls_keygen_types_t
GNUTLS_CIPHER_AES_128_SIV_GCM: Added
GNUTLS_CIPHER_AES_256_SIV_GCM: Added

* Version 3.8.1 (released 2023-08-03)

** libgnutls: ClientHello extensions are randomized by default
   To make fingerprinting harder, TLS extensions in ClientHello
   messages are shuffled. As this behavior may cause compatibility
   issue with legacy applications that do not accept the last
   extension without payload, the behavior can be reverted with the
   %NO_SHUFFLE_EXTENSIONS priority keyword.

** libgnutls: Add support for RFC 9258 external PSK importer.
   This enables to deploy the same PSK across multiple TLS versions
   (TLS 1.2 and TLS 1.3) in a secure manner. To use, the application
   needs to set up a callback that formats the PSK identity using
   gnutls_psk_format_imported_identity().

** libgnutls: %GNUTLS_NO_EXTENSIONS has been renamed to
   %GNUTLS_NO_DEFAULT_EXTENSIONS.

** libgnutls: Add additional PBKDF limit checks in FIPS mode as
   defined in SP 800-132. Minimum salt length is 128 bits and
   minimum iterations bound is 1000 for PBKDF in FIPS mode.

** libgnutls: Add a mechanism to control whether to enforce extended
   master secret (RFC 7627). FIPS 140-3 mandates the use of TLS
   session hash (extended master secret, EMS) in TLS 1.2. To enforce
   this, a new priority keyword %FORCE_SESSION_HASH is added and if
   it is set and EMS is not set, the peer aborts the connection. This
   behavior is the default in FIPS mode, though it can be overridden
   through the configuration file with the "tls-session-hash" option.
   In either case non-EMS PRF is reported as a non-approved operation
   through the FIPS service indicator.

** New option --attime to specify current time.
   To make testing with different timestamp to the system easier, the
   tools doing certificate verification now provide a new option
   --attime, which takes an arbitrary time.

** API and ABI modifications:
gnutls_psk_client_credentials_function3: New typedef
gnutls_psk_server_credentials_function3: New typedef
gnutls_psk_set_server_credentials_function3: New function
gnutls_psk_set_client_credentials_function3: New function
gnutls_psk_format_imported_identity: New function
GNUTLS_PSK_KEY_EXT: New enum member of gnutls_psk_key_flags

* Version 3.8.0 (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]

** libgnutls: C++ library is now header only. All definitions from
   gnutlsxx.c have been moved into gnutlsxx.h. Users of the C++
   interface have two options:
   1. include gnutlsxx.h in their application and link against
      the C library. (default)
   2. include gnutlsxx.h in their application, compile with
      GNUTLS_GNUTLSXX_NO_HEADERONLY macro defined and link
      against the C++ library.

** libgnutls: GNUTLS_NO_STATUS_REQUEST flag and %NO_STATUS_REQUEST
   priority modifier have been added to allow disabling of the
   status_request TLS extension in the client side.

** libgnutls: TLS heartbeat is disabled by default.
   The heartbeat extension in TLS (RFC 6520) is not widely used given
   other implementations dropped support for it. To enable back
   support for it, supply --enable-heartbeat-support to configure
   script.

** libgnutls: SRP authentication is now disabled by default.
   It is disabled because the SRP authentication in TLS is not up to
   date with the latest TLS standards and its ciphersuites are based
   on the CBC mode and SHA-1.  To enable it back, supply
   --enable-srp-authentication option to configure script.

** libgnutls: All code has been indented using "indent -ppi1 -linux".
   CI/CD has been adjusted to catch regressions.  This is implemented
   through devel/indent-gnutls, devel/indent-maybe and .gitlab-ci.yml’s
   commit-check.  You may run devel/indent-gnutls to fix any
   indentation issues if you make code modifications.

** guile: Guile-bindings removed.
   They have been extracted into a separate project to reduce complexity
   and to simplify maintenance, see <https://gitlab.com/gnutls/guile/>.

** minitasn1: Upgraded to libtasn1 version 4.19.

** API and ABI modifications:
GNUTLS_NO_STATUS_REQUEST: New flag
GNUTLS_SRTP_AEAD_AES_128_GCM: New gnutls_srtp_profile_t enum member
GNUTLS_SRTP_AEAD_AES_256_GCM: New gnutls_srtp_profile_t enum member

* 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
   compatibility 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 failure 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 overridden 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
