mbedtls-2.16.9-bp153.2.5.1

- Security fix: [bsc#1189589, CVE-2021-24119]
  * Side-channel vulnerability in base64 PEM
  * Guard against strong local side channel attack against base64
    tables by making access aceess to them use constant flow code.
  * Add mbedtls-CVE-2021-24119.patch

- Update to version 2.16.9:
  * Reduce stack usage significantly during sliding window exponentiation.
  * Remove the zeroization of a pointer variable in AES rounds.
    It was valid but spurious and misleading since it looked like a mistaken
    attempt to zeroize the pointed-to buffer.
  * see https://github.com/ARMmbed/mbedtls/releases/tag/v2.16.9
- Update to version 2.16.8
  * Support building on e2k (Elbrus) architecture: correctly enable -Wformat-signedness,
    and fix the code that causes signed-one-bit-field and sign-compare warnings.
  * see https://github.com/ARMmbed/mbedtls/releases/tag/v2.16.8
- Update to version 2.16.7
  * Unify the example programs termination to call mbedtls_exit()
    instead of using a return command. This has been done to
    enable customization of the behavior in bare metal environments.
  * Abort the ClientHello writing function as soon as some extension
    doesn't fit into the record buffer. Previously, such extensions
    were silently dropped. As a consequence, the TLS handshake now
    fails when the output buffer is not large enough to hold the ClientHello.
  * The ECP module, enabled by MBEDTLS_ECP_C, now depends on MBEDTLS_CTR_DRBG_C,
    MBEDTLS_HMAC_DRBG_C, MBEDTLS_SHA512_C or MBEDTLS_SHA256_C for some side-channel
    coutermeasures. If side channels are not a concern, this dependency can be avoided
    by enabling the new option MBEDTLS_ECP_NO_INTERNAL_RNG.
  * see https://github.com/ARMmbed/mbedtls/releases/tag/v2.16.7
- Update to 2.16.6
  * CVE-2020-10932: Fixed side channel in ECC code that allowed an adversary with
    access to precise enough timing and memory access information (typically an
    untrusted operating system attacking a secure enclave) to fully recover
    an ECDSA private key (boo#1181468).
  * Fix a potentially remotely exploitable buffer overread in a
    DTLS client when parsing the Hello Verify Request message.
  Bugfix
  * Fix compilation failure when both MBEDTLS_SSL_PROTO_DTLS and
    MBEDTLS_SSL_HW_RECORD_ACCEL are enabled.
  * Fix a function name in a debug message. Contributed by Ercan Ozturk in
    [#3013].
- Cheanged License in changes file from  Apache-2.0 to
  Apache-2.0 OR GPL-2.0-or-later as the upstream package changed too

- Update to version 2.16.5:
  * Security improvements and bugfixes

- Update to version 2.16.3:
  * Security improvements and bugfixes

- Update to version 2.16.2:
  * Security improvements and bugfixes
- Use ninja to for build

- Update to version 2.16.0:
  Features
  * Add a new config.h option of MBEDTLS_CHECK_PARAMS that enables validation of parameters in the API. This allows detection of obvious misuses of the API, such as passing NULL pointers. The API of existing functions hasn't changed, but requirements on parameters have been made more explicit in the documentation. See the corresponding API documentation for each function to see for which parameter values it is defined. This feature is disabled by default. See its API documentation in config.h for additional steps you have to take when enabling it.
  API Changes
  * The following functions in the random generator modules have been deprecated and replaced as shown below. The new functions change the return type from void to int to allow returning error codes when using MBEDTLS_<MODULE>_ALT for the underlying AES or message digest primitive. Fixes #1798. mbedtls_ctr_drbg_update() -> mbedtls_ctr_drbg_update_ret() mbedtls_hmac_drbg_update() -> mbedtls_hmac_drbg_update_ret()
  * Extend ECDH interface to enable alternative implementations.
  * Deprecate error codes of the form MBEDTLS_ERR_xxx_INVALID_KEY_LENGTH for ARIA, CAMELLIA and Blowfish. These error codes will be replaced by the more generic per-module error codes MBEDTLS_ERR_xxx_BAD_INPUT_DATA.
  * Additional parameter validation checks have been added for the following modules - AES, ARIA, Blowfish, CAMELLIA, CCM, GCM, DHM, ECP, ECDSA, ECDH, ECJPAKE, SHA, Chacha20 and Poly1305, cipher, pk, RSA, and MPI. Where modules have had parameter validation added, existing parameter checks may have changed. Some modules, such as Chacha20 had existing parameter validation whereas other modules had little. This has now been changed so that the same level of validation is present in all modules, and that it is now optional with the MBEDTLS_CHECK_PARAMS flag which by default is off. That means that checks which were previously present by default will no longer be.
  New deprecations
  * Deprecate mbedtls_ctr_drbg_update() and mbedtls_hmac_drbg_update() in favor of functions that can return an error code.
  Bugfix
  * Fix for Clang, which was reporting a warning for the bignum.c inline assembly for AMD64 targets creating string literals greater than those permitted by the ISO C99 standard. Found by Aaron Jones. Fixes #482.
  * Fix runtime error in mbedtls_platform_entropy_poll() when run through qemu user emulation. Reported and fix suggested by randombit. Fixes #1212.
  * Fix an unsafe bounds check when restoring an SSL session from a ticket. This could lead to a buffer overflow, but only in case ticket authentication was broken. Reported and fix suggested by Guido Vranken in #659.
  * Add explicit integer to enumeration type casts to example program programs/pkey/gen_key which previously led to compilation failure on some toolchains. Reported by phoenixmcallister. Fixes #2170.
  * Clarify documentation of mbedtls_ssl_set_own_cert() regarding the absence of check for certificate/key matching. Reported by Attila Molnar, #507.
  * Fix double initialization of ECC hardware that made some accelerators hang.

- Library package version bumped to libmbedtls12

- Update to version 2.14.1: [bsc#1118727, CVE-2018-19608]
  Security
  * Fix timing variations and memory access variations in RSA PKCS#1 v1.5
    decryption that could lead to a Bleichenbacher-style padding oracle
    attack. In TLS, this affects servers that accept ciphersuites based on
    RSA decryption (i.e. ciphersuites whose name contains RSA but not
    (EC)DH(E)). Discovered by Eyal Ronen (Weizmann Institute),  Robert Gillham
    (University of Adelaide), Daniel Genkin (University of Michigan),
    Adi Shamir (Weizmann Institute), David Wong (NCC Group), and Yuval Yarom
    (University of Adelaide, Data61). The attack is described in more detail
    in the paper available here: http://cat.eyalro.net/cat.pdf  CVE-2018-19608
  * In mbedtls_mpi_write_binary(), don't leak the exact size of the number
    via branching and memory access patterns. An attacker who could submit
    a plaintext for RSA PKCS#1 v1.5 decryption but only observe the timing
    of the decryption and not its result could nonetheless decrypt RSA
    plaintexts and forge RSA signatures. Other asymmetric algorithms may
    have been similarly vulnerable. Reported by Eyal Ronen, Robert Gillham,
    Daniel Genkin, Adi Shamir, David Wong and Yuval Yarom.
  * Wipe sensitive buffers on the stack in the CTR_DRBG and HMAC_DRBG
    modules.
  API Changes
  * The new functions mbedtls_ctr_drbg_update_ret() and
    mbedtls_hmac_drbg_update_ret() are similar to mbedtls_ctr_drbg_update()
    and mbedtls_hmac_drbg_update() respectively, but the new functions
    report errors whereas the old functions return void. We recommend that
    applications use the new functions.
- Version 2.14.0:
  Security
  * Fix overly strict DN comparison when looking for CRLs belonging to a
    particular CA. This previously led to ignoring CRLs when the CRL's issuer
    name and the CA's subject name differed in their string encoding (e.g.,
    one using PrintableString and the other UTF8String) or in the choice of
    upper and lower case. Reported by Henrik Andersson of Bosch GmbH in issue
    [#1784].
  * Fix a flawed bounds check in server PSK hint parsing. In case the
    incoming message buffer was placed within the first 64KiB of address
    space and a PSK-(EC)DHE ciphersuite was used, this allowed an attacker
    to trigger a memory access up to 64KiB beyond the incoming message buffer,
    potentially leading to an application crash or information disclosure.
  * Fix mbedtls_mpi_is_prime() to use more rounds of probabilistic testing. The
    previous settings for the number of rounds made it practical for an
    adversary to construct non-primes that would be erroneously accepted as
    primes with high probability. This does not have an impact on the
    security of TLS, but can matter in other contexts with numbers chosen
    potentially by an adversary that should be prime and can be validated.
    For example, the number of rounds was enough to securely generate RSA key
    pairs or Diffie-Hellman parameters, but was insufficient to validate
    Diffie-Hellman parameters properly.
    See "Prime and Prejudice" by by Martin R. Albrecht and Jake Massimo and
    Kenneth G. Paterson and Juraj Somorovsky.
  Features
  * Add support for temporarily suspending expensive ECC computations after
    some configurable amount of operations. This is intended to be used in
    constrained, single-threaded systems where ECC is time consuming and can
    block other operations until they complete. This is disabled by default,
    but can be enabled by MBEDTLS_ECP_RESTARTABLE at compile time and
    configured by mbedtls_ecp_set_max_ops() at runtime. It applies to the new
    xxx_restartable functions in ECP, ECDSA, PK and X.509 (CRL not supported
    yet), and to existing functions in ECDH and SSL (currently only
    implemented client-side, for ECDHE-ECDSA ciphersuites in TLS 1.2,
    including client authentication).
  * Add support for Arm CPU DSP extensions to accelerate asymmetric key
    operations. On CPUs where the extensions are available, they can accelerate
    MPI multiplications used in ECC and RSA cryptography. Contributed by
    Aurelien Jarno.
  * Extend RSASSA-PSS signature to allow a smaller salt size. Previously, PSS
    signature always used a salt with the same length as the hash, and returned
    an error if this was not possible. Now the salt size may be up to two bytes
    shorter. This allows the library to support all hash and signature sizes
    that comply with FIPS 186-4, including SHA-512 with a 1024-bit key.
  * Add support for 128-bit keys in CTR_DRBG. Note that using keys shorter
    than 256 bits limits the security of generated material to 128 bits.
  API Changes
  * Add a common error code of `MBEDTLS_ERR_PLATFORM_FEATURE_UNSUPPORTED` for
    a feature that is not supported by underlying alternative
    implementations implementing cryptographic primitives. This is useful for
    hardware accelerators that don't implement all options or features.
  New deprecations
  * All module specific errors following the form
    MBEDTLS_ERR_XXX_FEATURE_UNAVAILABLE that indicate a feature is not
    supported are deprecated and are now replaced by the new equivalent
    platform error.
  * All module specific generic hardware acceleration errors following the
    form MBEDTLS_ERR_XXX_HW_ACCEL_FAILED that are deprecated and are replaced
    by the equivalent plaform error.
  * Deprecate the function mbedtls_mpi_is_prime() in favor of
    mbedtls_mpi_is_prime_ext() which allows specifying the number of
    Miller-Rabin rounds.
  Bugfix
  * Fix wrong order of freeing in programs/ssl/ssl_server2 example
    application leading to a memory leak in case both
    MBEDTLS_MEMORY_BUFFER_ALLOC_C and MBEDTLS_MEMORY_BACKTRACE are set.
    Fixes #2069.
  * Fix a bug in the update function for SSL ticket keys which previously
    invalidated keys of a lifetime of less than a 1s. Fixes #1968.
  * Fix failure in hmac_drbg in the benchmark sample application, when
    MBEDTLS_THREADING_C is defined. Found by TrinityTonic, #1095
  * Fix a bug in the record decryption routine ssl_decrypt_buf()
    which lead to accepting properly authenticated but improperly
    padded records in case of CBC ciphersuites using Encrypt-then-MAC.
  * Fix memory leak and freeing without initialization in the example
    program programs/x509/cert_write. Fixes #1422.
  * Ignore IV in mbedtls_cipher_set_iv() when the cipher mode is
    MBEDTLS_MODE_ECB. Found by ezdevelop. Fixes #1091.
  * Zeroize memory used for buffering or reassembling handshake messages
    after use.
  * Use `mbedtls_platform_zeroize()` instead of `memset()` for zeroization
    of sensitive data in the example programs aescrypt2 and crypt_and_hash.
  * Change the default string format used for various X.509 DN attributes to
    UTF8String. Previously, the use of the PrintableString format led to
    wildcards and non-ASCII characters being unusable in some DN attributes.
    Reported by raprepo in #1860 and by kevinpt in #468. Fix contributed by
    Thomas-Dee.
  * Fix compilation failure for configurations which use compile time
    replacements of standard calloc/free functions through the macros
    MBEDTLS_PLATFORM_CALLOC_MACRO and MBEDTLS_PLATFORM_FREE_MACRO.
    Reported by ole-de and ddhome2006. Fixes #882, #1642 and #1706.
  Changes
  * Removed support for Yotta as a build tool.
  * Add tests for session resumption in DTLS.
  * Close a test gap in (D)TLS between the client side and the server side:
    test the handling of large packets and small packets on the client side
    in the same way as on the server side.
  * Change the dtls_client and dtls_server samples to work by default over
    IPv6 and optionally by a build option over IPv4.
  * Change the use of Windows threading to use Microsoft Visual C++ runtime
    calls, rather than Win32 API calls directly. This is necessary to avoid
    conflict with C runtime usage. Found and fixed by irwir.
  * Remember the string format of X.509 DN attributes when replicating
    X.509 DNs. Previously, DN attributes were always written in their default
    string format (mostly PrintableString), which could lead to CRTs being
    created which used PrintableStrings in the issuer field even though the
    signing CA used UTF8Strings in its subject field; while X.509 compliant,
    such CRTs were rejected in some applications, e.g. some versions of
    Firefox, curl and GnuTLS. Reported in #1033 by Moschn. Fix contributed by
    Thomas-Dee.
  * Improve documentation of mbedtls_ssl_get_verify_result().
    Fixes #517 reported by github-monoculture.
  * Add MBEDTLS_MPI_GEN_PRIME_FLAG_LOW_ERR flag to mbedtls_mpi_gen_prime() and
    use it to reduce error probability in RSA key generation to levels mandated
    by FIPS-186-4.
- Version 2.13.1
  API Changes
  * Extend the platform module with an abstraction mbedtls_platform_gmtime_r()
    whose implementation should behave as a thread-safe version of gmtime().
    This allows users to configure such an implementation at compile time when
    the target system cannot be deduced automatically, by setting the option
    MBEDTLS_PLATFORM_GMTIME_R_ALT. At this stage Mbed TLS is only able to
    automatically select implementations for Windows and POSIX C libraries.
  Bugfix
  * Fix build failures on platforms where only gmtime() is available but
    neither gmtime_r() nor gmtime_s() are present. Fixes #1907.
- Version 2.13.0
  Security
  * Fix an issue in the X.509 module which could lead to a buffer overread
    during certificate extensions parsing. In case of receiving malformed
    input (extensions length field equal to 0), an illegal read of one byte
    beyond the input buffer is made. Found and analyzed by Nathan Crandall.
  Features
  * Add support for fragmentation of outgoing DTLS handshake messages. This
    is controlled by the maximum fragment length as set locally or negotiated
    with the peer, as well as by a new per-connection MTU option, set using
    mbedtls_ssl_set_mtu().
  * Add support for auto-adjustment of MTU to a safe value during the
    handshake when flights do not get through (RFC 6347, section 4.1.1.1,
    last paragraph).
  * Add support for packing multiple records within a single datagram,
    enabled by default.
  * Add support for buffering out-of-order handshake messages in DTLS.
    The maximum amount of RAM used for this can be controlled by the
    compile-time constant MBEDTLS_SSL_DTLS_MAX_BUFFERING defined
    in mbedtls/config.h.
  API Changes
  * Add function mbedtls_ssl_set_datagram_packing() to configure
    the use of datagram packing (enabled by default).
  Bugfix
  * Fix a potential memory leak in mbedtls_ssl_setup() function. An allocation
    failure in the function could lead to other buffers being leaked.
  * Fixes an issue with MBEDTLS_CHACHAPOLY_C which would not compile if
    MBEDTLS_ARC4_C and MBEDTLS_CIPHER_NULL_CIPHER weren't also defined. #1890
  * Fix a memory leak in ecp_mul_comb() if ecp_precompute_comb() fails.
    Fix contributed by Espressif Systems.
  * Add ecc extensions only if an ecc based ciphersuite is used.
    This improves compliance to RFC 4492, and as a result, solves
    interoperability issues with BouncyCastle. Raised by milenamil in #1157.
  * Replace printf with mbedtls_printf in the ARIA module. Found by
    TrinityTonic in #1908.
  * Fix potential use-after-free in mbedtls_ssl_get_max_frag_len()
    and mbedtls_ssl_get_record_expansion() after a session reset. Fixes #1941.
  * Fix a bug that caused SSL/TLS clients to incorrectly abort the handshake
    with TLS versions 1.1 and earlier when the server requested authentication
    without providing a list of CAs. This was due to an overly strict bounds
    check in parsing the CertificateRequest message,
    introduced in Mbed TLS 2.12.0. Fixes #1954.
  * Fix a miscalculation of the maximum record expansion in
    mbedtls_ssl_get_record_expansion() in case of ChachaPoly ciphersuites,
    or CBC ciphersuites in (D)TLS versions 1.1 or higher. Fixes #1913, #1914.
  * Fix undefined shifts with negative values in certificates parsing
    (found by Catena cyber using oss-fuzz)
  * Fix memory leak and free without initialization in pk_encrypt
    and pk_decrypt example programs. Reported by Brace Stout. Fixes #1128.
  * Remove redundant else statement. Raised by irwir. Fixes #1776.
  Changes
  * Copy headers preserving timestamps when doing a "make install".
    Contributed by xueruini.
  * Allow the forward declaration of public structs. Contributed by Dawid
    Drozd. Fixes #1215 raised by randombit.
  * Improve compatibility with some alternative CCM implementations by using
    CCM test vectors from RAM.
  * Add support for buffering of out-of-order handshake messages.
  * Add warnings to the documentation of the HKDF module to reduce the risk
    of misusing the mbedtls_hkdf_extract() and mbedtls_hkdf_expand()
    functions. Fixes #1775. Reported by Brian J. Murray.

- Update to version 2.12.0:
  * Security
    + Fixed a vulnerability in the TLS ciphersuites based on use of CBC and SHA-384 in DTLS/TLS 1.0 to 1.2, that allowed an active network attacker to partially recover the plaintext of messages under certains conditions by exploiting timing side-channels.
    + Fixed a vulnerability in TLS ciphersuites based on CBC, in DTLS/TLS 1.0 to 1.2, that allowed a local attacker, with the ability to execute code on the local machine as well as to manipulate network packets, to partially recover the plaintext of messages under certain conditions by using a cache attack targetting an internal MD/SHA buffer.
    + Added a counter-measure against a vulnerability in TLS ciphersuites based on CBC, in DTLS/TLS 1.0 to 1.2, that allowed a local attacker with the ability to execute code on the local machine as well as manipulate network packets, to partially recover the plaintext of messages certain conditions (see previous entry) by using a cache attack targeting the SSL input record buffer.
  * Features
    + Added new cryptographic primitives, the stream cipher Chacha20, one-time authenticator Poly1305 and AEAD construct Chacha20-Poly1305, as defined in RFC 7539. Contributed by Daniel King.
    + Added support for the CHACHA20-POLY1305 ciphersuites from RFC 7905.
    + Made the receive and transmit buffers independently configurable in size, for situations where the outgoing buffer can be fixed at a smaller size than the incoming buffer
    + Added support for the AES based key wrapping modes defined by NIST SP 800-38F algorithms KW and KWP and by RFC's 3394 and 5649.
    + Added platform support for the Haiku OS.
  * Bugfix
    + Fixed the key_app_writer example which was creating an invalid ASN.1 tag by writing an additional leading zero byte. Found by Aryeh R. #1257.
    + Fixed a C++ compilation error, caused by a variable named new. Found and fixed by Hirotaka Niisato. #1783.
    + Fixed the "no symbols" warning issued by ranlib when building on Mac OS X. Fix contributed by tabascoeye.
    + Clarified documentation for mbedtls_ssl_write() to include 0 as a valid return value. Found by @davidwu2000. #839.
    + Fixed a memory leak in mbedtls_x509_csr_parse(). Found and fixed by catenacyber, Philippe Antoine. #1623.
    + Added length checks to some TLS parsing functions. Found and fixed by Philippe Antoine from Catena cyber. #1663.
    + Remove unused headers included in x509.c. Found by Chris Hanson and fixed by Brendan Shanks. #992.
    + Fixed compilation error when MBEDTLS_ARC4_C is disabled and MBEDTLS_CIPHER_NULL_CIPHER is enabled. Found by TrinityTonic in #1719.
    + Fixed the inline assembly for the MPI multiply helper function for i386 and i386 with SSE2. Found by László Langó. #1550.
    + Fixed the namespacing in header files. Remove the mbedtls namespacing in the #include in the header files. #857.
    + Fixed a compiler warning of 'use before initialisation' in mbedtls_pk_parse_key(). Found by Martin Boye Petersen and fixed by Dawid Drozd.#1098.
    + Fixed decryption of zero length messages (which contain all padding) when a CBC based ciphersuite was used together with Encrypt-then-MAC.
    + Fixed the ssl_client2 example to send application data with 0-length content when the request_size argument is set to 0 as stated in the documentation. #1833.
    + Corrected the documentation for mbedtls_ssl_get_session(). This API has deep copy of the session, and the peer certificate is not lost. #926.
    + Fixed issues when building to the C99 standard, using -std=c99. Fixed by Nick Wilson.
  * Changes
    + Fails when receiving a TLS alert message with an invalid length, or invalid zero-length messages when using TLS 1.2. Contributed by Espressif Systems.
    + Changed the default behaviour of mbedtls_hkdf_extract() to return an error when calling with a NULL salt and non-zero salt length. Contributed by Brian J Murray
    + Change the shebang line in Perl scripts to look up perl in the PATH. Contributed by fbrosson.
    + Allow overriding the time on Windows via the platform-time abstraction. Fixed by Nick Wilson.
    + Use gmtime_r/gmtime_s for thread-safety. Fixed by Nick Wilson.

- Update to version 2.11.0:
  * Features
    + Added support for the XTS block cipher mode with AES (AES-XTS). Contributed by Aorimn in pull request #414.
    + Implemented the HMAC-based extract-and-expand key derivation function (HKDF) per RFC 5869. Contributed by Thomas Fossati.
    + For TLS servers, added support for offloading private key operations to an external cryptoprocessor. Private key operations can be asynchronous to allow non-blocking operation of the TLS server stack.
    + Added support for ARIA cipher (RFC 5794) and associated TLS ciphersuites (RFC 6209). ARIA is disabled by default. To enable, see MBEDTLS_ARIA_C in config.h.
    + Added support for the CCM* block cipher mode as defined in IEEE Std 802.15.4.
    + Added an additional block mode, OFB (Output Feedback) per NIST SP 800-38a, to the AES module and cipher abstraction module.
  * API Changes
    + Mbed TLS 2.11.0 maintains source code compatibility with the last minor version, Mbed TLS 2.9.0, but extends the interface with additional capabilities. Mbed TLS 2.11.0 modifies the ABI and increases the SOVERSION.
  * Bugfix
    + Fixed the cert_write example to handle certificates signed with elliptic curves as well as RSA. Fixes #777 found by dbedev.
    + Fixed the redefinition of _WIN32_WINNT, to avoid overriding a definition used by user applications. Found and fixed by Fabio Alessandrelli.
    + Fixed compilation warnings with the IAR toolchain on 32-bit platforms. Reported by rahmanih in #683.
    + Fixed an issue with MicroBlaze support in bn_mul.h which was causing the build to fail. Found by zv-io. Fixes #1651.
    + Fixed braces in mbedtls_memory_buffer_alloc_status(). Found by sbranden in #552.
    + Added the macro MBEDTLS_X509_MAX_FILE_PATH_LEN that enables the user to configure the maximum length of a file path that can be buffered when calling mbedtls_x509_crt_parse_path(). Fixes #492.
    + Fixed redundant declaration of mbedtls_ssl_list_ciphersuites. Raised by TrinityTonic in #1359.
- Changes for version 2.9.0:
  + Security
    + Fixed an issue in the X.509 module which could lead to a buffer overread during certificate validation. Additionally, the issue could also lead to unnecessary callback checks being made or to some validation checks to be omitted. The overread could be triggered remotely, while the other issues would require a non DER-compliant certificate to be correctly signed by a trusted CA, or a trusted CA with a non DER-compliant certificate. Found by luocm. Fixes #825.
    + Fixed the buffer length assertion in the ssl_parse_certificate_request() function which could lead to an arbitrary overread of the message buffer. The overreads could be caused by receiving a malformed algorithms section which was too short. In builds with debug output, this overread data was output with the debug data.
    + Fixed a client-side bug in the validation of the server's ciphersuite choice which could potentially lead to the client accepting a ciphersuite it didn't offer or a ciphersuite that could not be used with the TLS or DTLS version chosen by the server. This could lead to corruption of internal data structures for some configurations.
  * Features
    + Added an option of MBEDTLS_AES_FEWER_TABLES, to dynamically compute smaller AES tables during runtime, thereby reducing the RAM/ROM footprint by ~6KiB. Suggested and contributed by jkivilin.
    + Added initial support for Curve448 (RFC 7748). So far only mbedtls_ecp_mul() and ECDH primitive functions (mbedtls_ecdh_gen_public(), mbedtls_ecdh_compute_shared()) are supported for now. Contributed by Nicholas Wilson.
  * API Changes
    + Mbed TLS 2.9.0 maintains source code and binary compatibility with the last minor version, Mbed TLS 2.8.0, but extends the interface with additional capabilities.
    + Extended the API with the function of mbedtls_net_poll() to allow user applications to wait for a network context to become ready before reading or writing.
    + Added the function mbedtls_ssl_check_pending() to the public API to allow a check for whether more more data is pending to be processed in the internal message buffers. This function is necessary to determine the underlying transport when event-driven IO is used.
  * Bugfix
    + Fixed a spurious uninitialized variable warning in cmac.c. Fix independently contributed by Brian J Murray and David Brown.
    + Added missing dependencies in test suites that led to build failures in configurations that omit certain hashes or public-key algorithms. Fixes #1040.
    + Fixed a C89 incompatibility issue in benchmark.c. Contributed by Brendan Shanks. Fixes #1353.
    + Added missing dependencies for MBEDTLS_HAVE_TIME_DATE and MBEDTLS_VERSION_FEATURES in some test suites. Contributed by Deomid Ryabkov. Fixes #1299, #1475.
    + Fixed the Makefile build process for building shared libraries on Mac OS X. Fixed by mnacamura.
    + Fixed parsing of PKCS#8 encoded Elliptic Curve keys. Previously Mbed TLS was unable to parse keys which had only the optional parameters field of the ECPrivateKey structure. Found by Jethro Beekman, fixed in #1379.
    + Added an optimisation to return the plaintext data more quickly on unpadded CBC decryption, as stated in the mbedtls_cipher_update() documentation. Contributed by Andy Leiserson.
    + Fixed the overriding and ignoring of return values when parsing and writing to a file in the pk_sign program. Found by kevlut in #1142.
    + Added restrictions to the usage of the error code MBEDTLS_ERR_SSL_WANT_READ to situations where data needs to be fetched from the underlying transport in order to make progress. Previously, this error code was also occasionally returned when unexpected messages were being discarded, ignoring that further messages could potentially already be pending to be processed in the internal buffers; these cases led to deadlocks when event-driven I/O was used. Found and reported by Hubert Mis in #772.
    + Fixed buffer length assertions in the ssl_parse_certificate_request() function which led to a potential one byte overread of the message buffer.
    + Fixed invalid buffer sizes being passed to zlib during record compression and decompression.
    + Raised the soversion of libmbedcrypto to match the soversion of the maintained 2.7 branch. The soversion was increased in Mbed TLS version 2.7.1 to reflect breaking changes in that release, but the increment was missed in 2.8.0 and later releases outside of the 2.7 branch.