Provided by: openssl_3.0.2-0ubuntu1_amd64 bug


       migration_guide - OpenSSL migration guide


       See the individual manual pages for details.


       This guide details the changes required to migrate to new versions of OpenSSL.  Currently
       this covers OpenSSL 3.0. For earlier versions refer to
       <>.  For an overview of some of
       the key concepts introduced in OpenSSL 3.0 see crypto(7).


   Main Changes from OpenSSL 1.1.1
       Major Release

       OpenSSL 3.0 is a major release and consequently any application that currently uses an
       older version of OpenSSL will at the very least need to be recompiled in order to work
       with the new version. It is the intention that the large majority of applications will
       work unchanged with OpenSSL 3.0 if those applications previously worked with OpenSSL
       1.1.1. However this is not guaranteed and some changes may be required in some cases.
       Changes may also be required if applications need to take advantage of some of the new
       features available in OpenSSL 3.0 such as the availability of the FIPS module.

       License Change

       In previous versions, OpenSSL was licensed under the dual OpenSSL and SSLeay licenses
       <> (both licenses apply). From
       OpenSSL 3.0 this is replaced by the Apache License v2

       Providers and FIPS support

       One of the key changes from OpenSSL 1.1.1 is the introduction of the Provider concept.
       Providers collect together and make available algorithm implementations.  With OpenSSL 3.0
       it is possible to specify, either programmatically or via a config file, which providers
       you want to use for any given application.  OpenSSL 3.0 comes with 5 different providers
       as standard. Over time third parties may distribute additional providers that can be
       plugged into OpenSSL.  All algorithm implementations available via providers are accessed
       through the "high level" APIs (for example those functions prefixed with "EVP"). They
       cannot be accessed using the "Low Level APIs".

       One of the standard providers available is the FIPS provider. This makes available FIPS
       validated cryptographic algorithms.  The FIPS provider is disabled by default and needs to
       be enabled explicitly at configuration time using the "enable-fips" option. If it is
       enabled, the FIPS provider gets built and installed in addition to the other standard
       providers. No separate installation procedure is necessary.  There is however a dedicated
       "install_fips" make target, which serves the special purpose of installing only the FIPS
       provider into an existing OpenSSL installation.

       Not all algorithms may be available for the application at a particular moment.  If the
       application code uses any digest or cipher algorithm via the EVP interface, the
       application should verify the result of the EVP_EncryptInit(3), EVP_EncryptInit_ex(3), and
       EVP_DigestInit(3) functions. In case when the requested algorithm is not available, these
       functions will fail.

       See also "Legacy Algorithms" for information on the legacy provider.

       See also "Completing the installation of the FIPS Module" and "Using the FIPS Module in

       Low Level APIs

       OpenSSL has historically provided two sets of APIs for invoking cryptographic algorithms:
       the "high level" APIs (such as the "EVP" APIs) and the "low level" APIs. The high level
       APIs are typically designed to work across all algorithm types. The "low level" APIs are
       targeted at a specific algorithm implementation.  For example, the EVP APIs provide the
       functions EVP_EncryptInit_ex(3), EVP_EncryptUpdate(3) and EVP_EncryptFinal(3) to perform
       symmetric encryption. Those functions can be used with the algorithms AES, CHACHA, 3DES
       etc.  On the other hand, to do AES encryption using the low level APIs you would have to
       call AES specific functions such as AES_set_encrypt_key(3), AES_encrypt(3), and so on. The
       functions for 3DES are different.  Use of the low level APIs has been informally
       discouraged by the OpenSSL development team for a long time. However in OpenSSL 3.0 this
       is made more formal. All such low level APIs have been deprecated. You may still use them
       in your applications, but you may start to see deprecation warnings during compilation
       (dependent on compiler support for this). Deprecated APIs may be removed from future
       versions of OpenSSL so you are strongly encouraged to update your code to use the high
       level APIs instead.

       This is described in more detail in "Deprecation of Low Level Functions"

       Legacy Algorithms

       Some cryptographic algorithms such as MD2 and DES that were available via the EVP APIs are
       now considered legacy and their use is strongly discouraged.  These legacy EVP algorithms
       are still available in OpenSSL 3.0 but not by default. If you want to use them then you
       must load the legacy provider.  This can be as simple as a config file change, or can be
       done programmatically.  See OSSL_PROVIDER-legacy(7) for a complete list of algorithms.
       Applications using the EVP APIs to access these algorithms should instead use more modern
       algorithms. If that is not possible then these applications should ensure that the legacy
       provider has been loaded. This can be achieved either programmatically or via
       configuration. See crypto(7) man page for more information about providers.

       Engines and "METHOD" APIs

       The refactoring to support Providers conflicts internally with the APIs used to support
       engines, including the ENGINE API and any function that creates or modifies custom
       "METHODS" (for example EVP_MD_meth_new(3), EVP_CIPHER_meth_new(3), EVP_PKEY_meth_new(3),
       RSA_meth_new(3), EC_KEY_METHOD_new(3), etc.). These functions are being deprecated in
       OpenSSL 3.0, and users of these APIs should know that their use can likely bypass provider
       selection and configuration, with unintended consequences.  This is particularly relevant
       for applications written to use the OpenSSL 3.0 FIPS module, as detailed below. Authors
       and maintainers of external engines are strongly encouraged to refactor their code
       transforming engines into providers using the new Provider API and avoiding deprecated

       Support of legacy engines

       If openssl is not built without engine support or deprecated API support, engines will
       still work. However, their applicability will be limited.

       New algorithms provided via engines will still work.

       Engine-backed keys can be loaded via custom OSSL_STORE implementation.  In this case the
       EVP_PKEY objects created via ENGINE_load_private_key(3) will be concidered legacy and will
       continue to work.

       To ensure the future compatibility, the engines should be turned to providers.  To prefer
       the provider-based hardware offload, you can specify the default properties to prefer your

       Versioning Scheme

       The OpenSSL versioning scheme has changed with the OpenSSL 3.0 release. The new versioning
       scheme has this format:


       For OpenSSL 1.1.1 and below, different patch levels were indicated by a letter at the end
       of the release version number. This will no longer be used and instead the patch level is
       indicated by the final number in the version. A change in the second (MINOR) number
       indicates that new features may have been added. OpenSSL versions with the same major
       number are API and ABI compatible.  If the major number changes then API and ABI
       compatibility is not guaranteed.

       For more information, see OpenSSL_version(3).

       Other major new features

       Certificate Management Protocol (CMP, RFC 4210)

       This also covers CRMF (RFC 4211) and HTTP transfer (RFC 6712) See openssl-cmp(1) and
       OSSL_CMP_exec_certreq(3) as starting points.

       HTTP(S) client

       A proper HTTP(S) client that supports GET and POST, redirection, plain and ASN.1-encoded
       contents, proxies, and timeouts.

       Key Derivation Function API (EVP_KDF)

       This simplifies the process of adding new KDF and PRF implementations.

       Previously KDF algorithms had been shoe-horned into using the EVP_PKEY object which was
       not a logical mapping.  Existing applications that use KDF algorithms using EVP_PKEY
       (scrypt, TLS1 PRF and HKDF) may be slower as they use an EVP_KDF bridge internally.  All
       new applications should use the new EVP_KDF(3) interface.  See also "Key Derivation
       Function (KDF)" in OSSL_PROVIDER-default(7) and "Key Derivation Function (KDF)" in

       Message Authentication Code API (EVP_MAC)

       This simplifies the process of adding MAC implementations.

       This includes a generic EVP_PKEY to EVP_MAC bridge, to facilitate the continued use of
       MACs through raw private keys in functionality such as EVP_DigestSign(3) and

       All new applications should use the new EVP_MAC(3) interface.  See also "Message
       Authentication Code (MAC)" in OSSL_PROVIDER-default(7) and "Message Authentication Code
       (MAC)" in OSSL_PROVIDER-FIPS(7).

       Support for Linux Kernel TLS

       In order to use KTLS, support for it must be compiled in using the "enable-ktls"
       configuration option. It must also be enabled at run time using the SSL_OP_ENABLE_KTLS

       New Algorithms

       •   KDF algorithms "SINGLE STEP" and "SSH"

           See EVP_KDF-SS(7) and EVP_KDF-SSHKDF(7)

       •   MAC Algorithms "GMAC" and "KMAC"

           See EVP_MAC-GMAC(7) and EVP_MAC-KMAC(7).

       •   KEM Algorithm "RSASVE"

           See EVP_KEM-RSA(7).

       •   Cipher Algorithm "AES-SIV"

           See "SIV Mode" in EVP_EncryptInit(3).

       •   AES Key Wrap inverse ciphers supported by EVP layer.

           The inverse ciphers use AES decryption for wrapping, and AES encryption for
           unwrapping. The algorithms are: "AES-128-WRAP-INV", "AES-192-WRAP-INV",
           "AES-256-WRAP-INV", "AES-128-WRAP-PAD-INV", "AES-192-WRAP-PAD-INV" and

       •   CTS ciphers added to EVP layer.

           The algorithms are "AES-128-CBC-CTS", "AES-192-CBC-CTS", "AES-256-CBC-CTS",
           "CAMELLIA-128-CBC-CTS", "CAMELLIA-192-CBC-CTS" and "CAMELLIA-256-CBC-CTS".  CS1, CS2
           and CS3 variants are supported.

       CMS and PKCS#7 updates

       •   Added CAdES-BES signature verification support.

       •   Added CAdES-BES signature scheme and attributes support (RFC 5126) to CMS API.

       •   Added AuthEnvelopedData content type structure (RFC 5083) using AES_GCM

           This uses the AES-GCM parameter (RFC 5084) for the Cryptographic Message Syntax.  Its
           purpose is to support encryption and decryption of a digital envelope that is both
           authenticated and encrypted using AES GCM mode.

       •   PKCS7_get_octet_string(3) and PKCS7_type_is_other(3) were made public.

       PKCS#12 API updates

       The default algorithms for pkcs12 creation with the PKCS12_create() function were changed
       to more modern PBKDF2 and AES based algorithms. The default MAC iteration count was
       changed to PKCS12_DEFAULT_ITER to make it equal with the password-based encryption
       iteration count. The default digest algorithm for the MAC computation was changed to
       SHA-256. The pkcs12 application now supports -legacy option that restores the previous
       default algorithms to support interoperability with legacy systems.

       Added enhanced PKCS#12 APIs which accept a library context OSSL_LIB_CTX and (where
       relevant) a property query. Other APIs which handle PKCS#7 and PKCS#8 objects have also
       been enhanced where required. This includes:

       PKCS12_add_key_ex(3), PKCS12_add_safe_ex(3), PKCS12_add_safes_ex(3), PKCS12_create_ex(3),
       PKCS12_decrypt_skey_ex(3), PKCS12_init_ex(3), PKCS12_item_decrypt_d2i_ex(3),
       PKCS12_item_i2d_encrypt_ex(3), PKCS12_key_gen_asc_ex(3), PKCS12_key_gen_uni_ex(3),
       PKCS12_key_gen_utf8_ex(3), PKCS12_pack_p7encdata_ex(3), PKCS12_pbe_crypt_ex(3),
       PKCS12_PBE_keyivgen_ex(3), PKCS12_SAFEBAG_create_pkcs8_encrypt_ex(3),
       PKCS5_pbe2_set_iv_ex(3), PKCS5_pbe_set0_algor_ex(3), PKCS5_pbe_set_ex(3),
       PKCS5_pbkdf2_set_ex(3), PKCS5_v2_PBE_keyivgen_ex(3), PKCS5_v2_scrypt_keyivgen_ex(3),
       PKCS8_decrypt_ex(3), PKCS8_encrypt_ex(3), PKCS8_set0_pbe_ex(3).

       As part of this change the EVP_PBE_xxx APIs can also accept a library context and property
       query and will call an extended version of the key/IV derivation function which supports
       these parameters. This includes EVP_PBE_CipherInit_ex(3), EVP_PBE_find_ex(3) and

       Windows thread synchronization changes

       Windows thread synchronization uses read/write primitives (SRWLock) when supported by the
       OS, otherwise CriticalSection continues to be used.

       Trace API

       A new generic trace API has been added which provides support for enabling instrumentation
       through trace output. This feature is mainly intended as an aid for developers and is
       disabled by default. To utilize it, OpenSSL needs to be configured with the "enable-trace"

       If the tracing API is enabled, the application can activate trace output by registering
       BIOs as trace channels for a number of tracing and debugging categories. See

       Key validation updates

       EVP_PKEY_public_check(3) and EVP_PKEY_param_check(3) now work for more key types. This
       includes RSA, DSA, ED25519, X25519, ED448 and X448.  Previously (in 1.1.1) they would
       return -2. For key types that do not have parameters then EVP_PKEY_param_check(3) will
       always return 1.

       Other notable deprecations and changes

       The function code part of an OpenSSL error code is no longer relevant

       This code is now always set to zero. Related functions are deprecated.

       STACK and HASH macros have been cleaned up

       The type-safe wrappers are declared everywhere and implemented once.  See

       The RAND_DRBG subsystem has been removed

       The new EVP_RAND(3) is a partial replacement: the DRBG callback framework is absent. The
       RAND_DRBG API did not fit well into the new provider concept as implemented by EVP_RAND
       and EVP_RAND_CTX.

       Removed FIPS_mode() and FIPS_mode_set()

       These functions are legacy APIs that are not applicable to the new provider model.
       Applications should instead use EVP_default_properties_is_fips_enabled(3) and

       Key generation is slower

       The Miller-Rabin test now uses 64 rounds, which is used for all prime generation,
       including RSA key generation. This affects the time for larger keys sizes.

       The default key generation method for the regular 2-prime RSA keys was changed to the FIPS
       186-4 B.3.6 method (Generation of Probable Primes with Conditions Based on Auxiliary
       Probable Primes). This method is slower than the original method.

       Change PBKDF2 to conform to SP800-132 instead of the older PKCS5 RFC2898

       This checks that the salt length is at least 128 bits, the derived key length is at least
       112 bits, and that the iteration count is at least 1000.  For backwards compatibility
       these checks are disabled by default in the default provider, but are enabled by default
       in the fips provider.

       To enable or disable the checks see OSSL_KDF_PARAM_PKCS5 in EVP_KDF-PBKDF2(7). The
       parameter can be set using EVP_KDF_derive(3).

       Enforce a minimum DH modulus size of 512 bits

       Smaller sizes now result in an error.

       SM2 key changes

       EC EVP_PKEYs with the SM2 curve have been reworked to automatically become EVP_PKEY_SM2
       rather than EVP_PKEY_EC.

       Unlike in previous OpenSSL versions, this means that applications cannot call
       "EVP_PKEY_set_alias_type(pkey, EVP_PKEY_SM2)" to get SM2 computations.

       Parameter and key generation is also reworked to make it possible to generate EVP_PKEY_SM2
       parameters and keys. Applications must now generate SM2 keys directly and must not create
       an EVP_PKEY_EC key first. It is no longer possible to import an SM2 key with domain
       parameters other than the SM2 elliptic curve ones.

       Validation of SM2 keys has been separated from the validation of regular EC keys, allowing
       to improve the SM2 validation process to reject loaded private keys that are not
       conforming to the SM2 ISO standard.  In particular, a private scalar k outside the range 1
       <= k < n-1 is now correctly rejected.

       EVP_PKEY_set_alias_type() method has been removed

       This function made a EVP_PKEY object mutable after it had been set up. In OpenSSL 3.0 it
       was decided that a provided key should not be able to change its type, so this function
       has been removed.

       Functions that return an internal key should be treated as read only

       Functions such as EVP_PKEY_get0_RSA(3) behave slightly differently in OpenSSL 3.0.
       Previously they returned a pointer to the low-level key used internally by libcrypto. From
       OpenSSL 3.0 this key may now be held in a provider. Calling these functions will only
       return a handle on the internal key where the EVP_PKEY was constructed using this key in
       the first place, for example using a function or macro such as EVP_PKEY_assign_RSA(3),
       EVP_PKEY_set1_RSA(3), etc.  Where the EVP_PKEY holds a provider managed key, then these
       functions now return a cached copy of the key. Changes to the internal provider key that
       take place after the first time the cached key is accessed will not be reflected back in
       the cached copy. Similarly any changes made to the cached copy by application code will
       not be reflected back in the internal provider key.

       For the above reasons the keys returned from these functions should typically be treated
       as read-only. To emphasise this the value returned from EVP_PKEY_get0_RSA(3),
       EVP_PKEY_get0_DSA(3), EVP_PKEY_get0_EC_KEY(3) and EVP_PKEY_get0_DH(3) have been made
       const. This may break some existing code.  Applications broken by this change should be
       modified. The preferred solution is to refactor the code to avoid the use of these
       deprecated functions. Failing this the code should be modified to use a const pointer
       instead.  The EVP_PKEY_get1_RSA(3), EVP_PKEY_get1_DSA(3), EVP_PKEY_get1_EC_KEY(3) and
       EVP_PKEY_get1_DH(3) functions continue to return a non-const pointer to enable them to be
       "freed". However they should also be treated as read-only.

       The public key check has moved from EVP_PKEY_derive() to EVP_PKEY_derive_set_peer()

       This may mean result in an error in EVP_PKEY_derive_set_peer(3) rather than during
       EVP_PKEY_derive(3).  To disable this check use EVP_PKEY_derive_set_peer_ex(dh, peer, 0).

       The print format has cosmetic changes for some functions

       The output from numerous "printing" functions such as X509_signature_print(3),
       X509_print_ex(3), X509_CRL_print_ex(3), and other similar functions has been amended such
       that there may be cosmetic differences between the output observed in 1.1.1 and 3.0. This
       also applies to the -text output from the openssl x509 and openssl crl applications.

       Interactive mode from the openssl program has been removed

       From now on, running it without arguments is equivalent to openssl help.

       The error return values from some control calls (ctrl) have changed

       One significant change is that controls which used to return -2 for invalid inputs, now
       return -1 indicating a generic error condition instead.

       DH and DHX key types have different settable parameters

       Previously (in 1.1.1) these conflicting parameters were allowed, but will now result in
       errors. See EVP_PKEY-DH(7) for further details. This affects the behaviour of
       openssl-genpkey(1) for DH parameter generation.

       EVP_CIPHER_CTX_set_flags() ordering change

       If using a cipher from a provider the EVP_CIPH_FLAG_LENGTH_BITS flag can only be set after
       the cipher has been assigned to the cipher context.  See "FLAGS" in EVP_EncryptInit(3) for
       more information.

       Validation of operation context parameters

       Due to move of the implementation of cryptographic operations to the providers, validation
       of various operation parameters can be postponed until the actual operation is executed
       where previously it happened immediately when an operation parameter was set.

       For example when setting an unsupported curve with
       EVP_PKEY_CTX_set_ec_paramgen_curve_nid() this function call will not fail but later keygen
       operations with the EVP_PKEY_CTX will fail.

       Removal of function code from the error codes

       The function code part of the error code is now always set to 0. For that reason the
       ERR_GET_FUNC() macro was removed. Applications must resolve the error codes only using the
       library number and the reason code.

   Installation and Compilation
       Please refer to the file in the top of the distribution for instructions on how
       to build and install OpenSSL 3.0. Please also refer to the various platform specific NOTES
       files for your specific platform.

   Upgrading from OpenSSL 1.1.1
       Upgrading to OpenSSL 3.0 from OpenSSL 1.1.1 should be relatively straight forward in most
       cases. The most likely area where you will encounter problems is if you have used low
       level APIs in your code (as discussed above). In that case you are likely to start seeing
       deprecation warnings when compiling your application. If this happens you have 3 options:

       1.  Ignore the warnings. They are just warnings. The deprecated functions are still
           present and you may still use them. However be aware that they may be removed from a
           future version of OpenSSL.

       2.  Suppress the warnings. Refer to your compiler documentation on how to do this.

       3.  Remove your usage of the low level APIs. In this case you will need to rewrite your
           code to use the high level APIs instead

       Error code changes

       As OpenSSL 3.0 provides a brand new Encoder/Decoder mechanism for working with widely used
       file formats, application code that checks for particular error reason codes on key
       loading failures might need an update.

       Password-protected keys may deserve special attention. If only some errors are treated as
       an indicator that the user should be asked about the password again, it's worth testing
       these scenarios and processing the newly relevant codes.

       There may be more cases to treat specially, depending on the calling application code.

   Upgrading from OpenSSL 1.0.2
       Upgrading to OpenSSL 3.0 from OpenSSL 1.0.2 is likely to be significantly more difficult.
       In addition to the issues discussed above in the section about "Upgrading from OpenSSL
       1.1.1", the main things to be aware of are:

       1.  The build and installation procedure has changed significantly.

           Check the file in the top of the installation for instructions on how to
           build and install OpenSSL for your platform. Also read the various NOTES files in the
           same directory, as applicable for your platform.

       2.  Many structures have been made opaque in OpenSSL 3.0.

           The structure definitions have been removed from the public header files and moved to
           internal header files. In practice this means that you can no longer stack allocate
           some structures. Instead they must be heap allocated through some function call
           (typically those function names have a "_new" suffix to them).  Additionally you must
           use "setter" or "getter" functions to access the fields within those structures.

           For example code that previously looked like this:

            EVP_MD_CTX md_ctx;

            /* This line will now generate compiler errors */

           The code needs to be amended to look like this:

            EVP_MD_CTX *md_ctx;

            md_ctx = EVP_MD_CTX_new();

       3.  Support for TLSv1.3 has been added.

           This has a number of implications for SSL/TLS applications. See the TLS1.3 page
           <> for further details.

       More details about the breaking changes between OpenSSL versions 1.0.2 and 1.1.0 can be
       found on the OpenSSL 1.1.0 Changes page

       Upgrading from the OpenSSL 2.0 FIPS Object Module

       The OpenSSL 2.0 FIPS Object Module was a separate download that had to be built separately
       and then integrated into your main OpenSSL 1.0.2 build.  In OpenSSL 3.0 the FIPS support
       is fully integrated into the mainline version of OpenSSL and is no longer a separate
       download. For further information see "Completing the installation of the FIPS Module".

       The function calls FIPS_mode() and FIPS_mode_set() have been removed from OpenSSL 3.0. You
       should rewrite your application to not use them.  See fips_module(7) and
       OSSL_PROVIDER-FIPS(7) for details.

   Completing the installation of the FIPS Module
       The FIPS Module will be built and installed automatically if FIPS support has been
       configured. The current documentation can be found in the README-FIPS
       <> file.

       Applications written to work with OpenSSL 1.1.1 will mostly just work with OpenSSL 3.0.
       However changes will be required if you want to take advantage of some of the new features
       that OpenSSL 3.0 makes available. In order to do that you need to understand some new
       concepts introduced in OpenSSL 3.0.  Read "Library contexts" in crypto(7) for further

       Library Context

       A library context allows different components of a complex application to each use a
       different library context and have different providers loaded with different configuration
       settings.  See "Library contexts" in crypto(7) for further info.

       If the user creates an OSSL_LIB_CTX via OSSL_LIB_CTX_new(3) then many functions may need
       to be changed to pass additional parameters to handle the library context.

       Using a Library Context - Old functions that should be changed

       If a library context is needed then all EVP_* digest functions that return a const EVP_MD
       * such as EVP_sha256() should be replaced with a call to EVP_MD_fetch(3). See "ALGORITHM
       FETCHING" in crypto(7).

       If a library context is needed then all EVP_* cipher functions that return a const
       EVP_CIPHER * such as EVP_aes_128_cbc() should be replaced vith a call to
       EVP_CIPHER_fetch(3). See "ALGORITHM FETCHING" in crypto(7).

       Some functions can be passed an object that has already been set up with a library context
       such as d2i_X509(3), d2i_X509_CRL(3), d2i_X509_REQ(3) and d2i_X509_PUBKEY(3). If NULL is
       passed instead then the created object will be set up with the default library context.
       Use X509_new_ex(3), X509_CRL_new_ex(3), X509_REQ_new_ex(3) and X509_PUBKEY_new_ex(3) if a
       library context is required.

       All functions listed below with a NAME have a replacment function NAME_ex that takes
       OSSL_LIB_CTX as an additional argument. Functions that have other mappings are listed
       along with the respective name.

       •   ASN1_item_new(3), ASN1_item_d2i(3), ASN1_item_d2i_fp(3), ASN1_item_d2i_bio(3),
           ASN1_item_sign(3) and ASN1_item_verify(3)

       •   BIO_new(3)

       •   b2i_RSA_PVK_bio() and i2b_PVK_bio()BN_CTX_new(3) and BN_CTX_secure_new(3)

       •   CMS_AuthEnvelopedData_create(3), CMS_ContentInfo_new(3), CMS_data_create(3),
           CMS_digest_create(3), CMS_EncryptedData_encrypt(3), CMS_encrypt(3),
           CMS_EnvelopedData_create(3), CMS_ReceiptRequest_create0(3) and CMS_sign(3)

       •   CONF_modules_load_file(3)

       •   CTLOG_new(3), CTLOG_new_from_base64(3) and CTLOG_STORE_new(3)

       •   CT_POLICY_EVAL_CTX_new(3)

       •   d2i_AutoPrivateKey(3), d2i_PrivateKey(3) and d2i_PUBKEY(3)

       •   d2i_PrivateKey_bio(3) and d2i_PrivateKey_fp(3)

           Use d2i_PrivateKey_ex_bio(3) and d2i_PrivateKey_ex_fp(3)

       •   EC_GROUP_new(3)

           Use EC_GROUP_new_by_curve_name_ex(3) or EC_GROUP_new_from_params(3).

       •   EVP_DigestSignInit(3) and EVP_DigestVerifyInit(3)

       •   EVP_PBE_CipherInit(3), EVP_PBE_find(3) and EVP_PBE_scrypt(3)

       •   PKCS5_PBE_keyivgen(3)

       •   EVP_PKCS82PKEY(3)

       •   EVP_PKEY_CTX_new_id(3)

           Use EVP_PKEY_CTX_new_from_name(3)

       •   EVP_PKEY_derive_set_peer(3), EVP_PKEY_new_raw_private_key(3) and

       •   EVP_SignFinal(3) and EVP_VerifyFinal(3)

       •   NCONF_new(3)

       •   OCSP_RESPID_match(3) and OCSP_RESPID_set_by_key(3)

       •   OPENSSL_thread_stop(3)

       •   OSSL_STORE_open(3)

       •   PEM_read_bio_Parameters(3), PEM_read_bio_PrivateKey(3), PEM_read_bio_PUBKEY(3),
           PEM_read_PrivateKey(3) and PEM_read_PUBKEY(3)

       •   PEM_write_bio_PrivateKey(3), PEM_write_bio_PUBKEY(3), PEM_write_PrivateKey(3) and

       •   PEM_X509_INFO_read_bio(3) and PEM_X509_INFO_read(3)

       •   PKCS12_add_key(3), PKCS12_add_safe(3), PKCS12_add_safes(3), PKCS12_create(3),
           PKCS12_decrypt_skey(3), PKCS12_init(3), PKCS12_item_decrypt_d2i(3),
           PKCS12_item_i2d_encrypt(3), PKCS12_key_gen_asc(3), PKCS12_key_gen_uni(3),
           PKCS12_key_gen_utf8(3), PKCS12_pack_p7encdata(3), PKCS12_pbe_crypt(3),
           PKCS12_PBE_keyivgen(3), PKCS12_SAFEBAG_create_pkcs8_encrypt(3)

       •   PKCS5_pbe_set0_algor(3), PKCS5_pbe_set(3), PKCS5_pbe2_set_iv(3), PKCS5_pbkdf2_set(3)
           and PKCS5_v2_scrypt_keyivgen(3)

       •   PKCS7_encrypt(3), PKCS7_new(3) and PKCS7_sign(3)

       •   PKCS8_decrypt(3), PKCS8_encrypt(3) and PKCS8_set0_pbe(3)

       •   RAND_bytes(3) and RAND_priv_bytes(3)

       •   SMIME_write_ASN1(3)

       •   SSL_load_client_CA_file(3)

       •   SSL_CTX_new(3)

       •   TS_RESP_CTX_new(3)

       •   X509_CRL_new(3)

       •   X509_load_cert_crl_file(3) and X509_load_cert_file(3)

       •   X509_LOOKUP_by_subject(3) and X509_LOOKUP_ctrl(3)

       •   X509_NAME_hash(3)

       •   X509_new(3)

       •   X509_REQ_new(3) and X509_REQ_verify(3)

       •   X509_STORE_CTX_new(3), X509_STORE_set_default_paths(3), X509_STORE_load_file(3),
           X509_STORE_load_locations(3) and X509_STORE_load_store(3)

       New functions that use a Library context

       The following functions can be passed a library context if required.  Passing NULL will
       use the default library context.

       •   BIO_new_from_core_bio(3)

       •   EVP_ASYM_CIPHER_fetch(3) and EVP_ASYM_CIPHER_do_all_provided(3)

       •   EVP_CIPHER_fetch(3) and EVP_CIPHER_do_all_provided(3)

       •   EVP_default_properties_enable_fips(3) and EVP_default_properties_is_fips_enabled(3)

       •   EVP_KDF_fetch(3) and EVP_KDF_do_all_provided(3)

       •   EVP_KEM_fetch(3) and EVP_KEM_do_all_provided(3)

       •   EVP_KEYEXCH_fetch(3) and EVP_KEYEXCH_do_all_provided(3)

       •   EVP_KEYMGMT_fetch(3) and EVP_KEYMGMT_do_all_provided(3)

       •   EVP_MAC_fetch(3) and EVP_MAC_do_all_provided(3)

       •   EVP_MD_fetch(3) and EVP_MD_do_all_provided(3)

       •   EVP_PKEY_CTX_new_from_pkey(3)

       •   EVP_PKEY_Q_keygen(3)

       •   EVP_Q_mac(3) and EVP_Q_digest(3)

       •   EVP_RAND(3) and EVP_RAND_do_all_provided(3)

       •   EVP_set_default_properties(3)

       •   EVP_SIGNATURE_fetch(3) and EVP_SIGNATURE_do_all_provided(3)

       •   OSSL_CMP_CTX_new(3) and OSSL_CMP_SRV_CTX_new(3)

       •   OSSL_CRMF_ENCRYPTEDVALUE_get1_encCert(3)

       •   OSSL_CRMF_MSG_create_popo(3) and OSSL_CRMF_MSGS_verify_popo(3)

       •   OSSL_CRMF_pbm_new(3) and OSSL_CRMF_pbmp_new(3)

       •   OSSL_DECODER_CTX_add_extra(3) and OSSL_DECODER_CTX_new_for_pkey(3)

       •   OSSL_DECODER_fetch(3) and OSSL_DECODER_do_all_provided(3)

       •   OSSL_ENCODER_CTX_add_extra(3)

       •   OSSL_ENCODER_fetch(3) and OSSL_ENCODER_do_all_provided(3)

       •   OSSL_LIB_CTX_free(3), OSSL_LIB_CTX_load_config(3) and OSSL_LIB_CTX_set0_default(3)

       •   OSSL_PROVIDER_add_builtin(3), OSSL_PROVIDER_available(3), OSSL_PROVIDER_do_all(3),
           OSSL_PROVIDER_load(3), OSSL_PROVIDER_set_default_search_path(3) and

       •   OSSL_SELF_TEST_get_callback(3) and OSSL_SELF_TEST_set_callback(3)

       •   OSSL_STORE_attach(3)

       •   OSSL_STORE_LOADER_fetch(3) and OSSL_STORE_LOADER_do_all_provided(3)

       •   RAND_get0_primary(3), RAND_get0_private(3), RAND_get0_public(3), RAND_set_DRBG_type(3)
           and RAND_set_seed_source_type(3)


       Providers are described in detail here "Providers" in crypto(7).  See also "OPENSSL
       PROVIDERS" in crypto(7).

       Fetching algorithms and property queries

       Implicit and Explicit Fetching is described in detail here "ALGORITHM FETCHING" in

       Mapping EVP controls and flags to provider OSSL_PARAM parameters

       The existing functions for controls (such as EVP_CIPHER_CTX_ctrl(3)) and manipulating
       flags (such as EVP_MD_CTX_set_flags(3))internally use OSSL_PARAMS to pass information
       to/from provider objects.  See OSSL_PARAM(3) for additional information related to

       For ciphers see "CONTROLS" in EVP_EncryptInit(3), "FLAGS" in EVP_EncryptInit(3) and
       "PARAMETERS" in EVP_EncryptInit(3).

       For digests see "CONTROLS" in EVP_DigestInit(3), "FLAGS" in EVP_DigestInit(3) and
       "PARAMETERS" in EVP_DigestInit(3).

       Deprecation of Low Level Functions

       A significant number of APIs have been deprecated in OpenSSL 3.0.  This section describes
       some common categories of deprecations.  See "Deprecated function mappings" for the list
       of deprecated functions that refer to these categories.

       Providers are a replacement for engines and low-level method overrides

       Any accessor that uses an ENGINE is deprecated (such as EVP_PKEY_set1_engine()).
       Applications using engines should instead use providers.

       Before providers were added algorithms were overriden by changing the methods used by
       algorithms. All these methods such as RSA_new_method() and RSA_meth_new() are now
       deprecated and can be replaced by using providers instead.

       Deprecated i2d and d2i functions for low-level key types

       Any i2d and d2i functions such as d2i_DHparams() that take a low-level key type have been
       deprecated. Applications should instead use the OSSL_DECODER(3) and OSSL_ENCODER(3) APIs
       to read and write files.  See "Migration" in d2i_RSAPrivateKey(3) for further details.

       Deprecated low-level key object getters and setters

       Applications that set or get low-level key objects (such as EVP_PKEY_set1_DH() or
       EVP_PKEY_get0()) should instead use the OSSL_ENCODER (See OSSL_ENCODER_to_bio(3)) or
       OSSL_DECODER (See OSSL_DECODER_from_bio(3)) APIs, or alternatively use
       EVP_PKEY_fromdata(3) or EVP_PKEY_todata(3).

       Deprecated low-level key parameter getters

       Functions that access low-level objects directly such as RSA_get0_n(3) are now deprecated.
       Applications should use one of EVP_PKEY_get_bn_param(3), EVP_PKEY_get_int_param(3),
       l<EVP_PKEY_get_size_t_param(3)>, EVP_PKEY_get_utf8_string_param(3),
       EVP_PKEY_get_octet_string_param(3) or EVP_PKEY_get_params(3) to access fields from an
       EVP_PKEY.  Gettable parameters are listed in "Common RSA parameters" in EVP_PKEY-RSA(7),
       "DH parameters" in EVP_PKEY-DH(7), "DSA parameters" in EVP_PKEY-DSA(7), "FFC parameters"
       in EVP_PKEY-FFC(7), "Common EC parameters" in EVP_PKEY-EC(7) and "Common X25519, X448,
       ED25519 and ED448 parameters" in EVP_PKEY-X25519(7).  Applications may also use
       EVP_PKEY_todata(3) to return all fields.

       Deprecated low-level key parameter setters

       Functions that access low-level objects directly such as RSA_set0_crt_params(3) are now
       deprecated. Applications should use EVP_PKEY_fromdata(3) to create new keys from user
       provided key data. Keys should be immutable once they are created, so if required the user
       may use EVP_PKEY_todata(3), OSSL_PARAM_merge(3), and EVP_PKEY_fromdata(3) to create a
       modified key.  See "Examples" in EVP_PKEY-DH(7) for more information.  See "Deprecated
       low-level key generation functions" for information on generating a key using parameters.

       Deprecated low-level object creation

       Low-level objects were created using methods such as RSA_new(3), RSA_up_ref(3) and
       RSA_free(3). Applications should instead use the high-level EVP_PKEY APIs, e.g.
       EVP_PKEY_new(3), EVP_PKEY_up_ref(3) and EVP_PKEY_free(3).  See also
       EVP_PKEY_CTX_new_from_name(3) and EVP_PKEY_CTX_new_from_pkey(3).

       EVP_PKEYs may be created in a variety of ways: See also "Deprecated low-level key
       generation functions", "Deprecated low-level key reading and writing functions" and
       "Deprecated low-level key parameter setters".

       Deprecated low-level encryption functions

       Low-level encryption functions such as AES_encrypt(3) and AES_decrypt(3) have been
       informally discouraged from use for a long time. Applications should instead use the high
       level EVP APIs EVP_EncryptInit_ex(3), EVP_EncryptUpdate(3), and EVP_EncryptFinal_ex(3) or
       EVP_DecryptInit_ex(3), EVP_DecryptUpdate(3) and EVP_DecryptFinal_ex(3).

       Deprecated low-level digest functions

       Use of low-level digest functions such as SHA1_Init(3) have been informally discouraged
       from use for a long time.  Applications should instead use the the high level EVP APIs
       EVP_DigestInit_ex(3), EVP_DigestUpdate(3) and EVP_DigestFinal_ex(3), or the quick one-shot

       Note that the functions SHA1(3), SHA224(3), SHA256(3), SHA384(3) and SHA512(3) have
       changed to macros that use EVP_Q_digest(3).

       Deprecated low-level signing functions

       Use of low-level signing functions such as DSA_sign(3) have been informally discouraged
       for a long time. Instead applications should use EVP_DigestSign(3) and
       EVP_DigestVerify(3).  See also EVP_SIGNATURE-RSA(7), EVP_SIGNATURE-DSA(7),

       Deprecated low-level MAC functions

       Low-level mac functions such as CMAC_Init(3) are deprecated.  Applications should instead
       use the new EVP_MAC(3) interface, using EVP_MAC_CTX_new(3), EVP_MAC_CTX_free(3),
       EVP_MAC_init(3), EVP_MAC_update(3) and EVP_MAC_final(3) or the single-shot MAC function
       EVP_Q_mac(3).  See EVP_MAC(3), EVP_MAC-HMAC(7), EVP_MAC-CMAC(7), EVP_MAC-GMAC(7),
       EVP_MAC-KMAC(7), EVP_MAC-BLAKE2(7), EVP_MAC-Poly1305(7) and EVP_MAC-Siphash(7) for
       additional information.

       Note that the one-shot method HMAC() is still available for compatability purposes.

       Deprecated low-level validation functions

       Low-level validation functions such as DH_check(3) have been informally discouraged from
       use for a long time. Applications should instead use the high-level EVP_PKEY APIs such as
       EVP_PKEY_check(3), EVP_PKEY_param_check(3), EVP_PKEY_param_check_quick(3),
       EVP_PKEY_public_check(3), EVP_PKEY_public_check_quick(3), EVP_PKEY_private_check(3), and

       Deprecated low-level key exchange functions

       Many low-level functions have been informally discouraged from use for a long time.
       Applications should instead use EVP_PKEY_derive(3).  See EVP_KEYEXCH-DH(7),
       EVP_KEYEXCH-ECDH(7) and EVP_KEYEXCH-X25519(7).

       Deprecated low-level key generation functions

       Many low-level functions have been informally discouraged from use for a long time.
       Applications should instead use EVP_PKEY_keygen_init(3) and EVP_PKEY_generate(3) as
       described in EVP_PKEY-DSA(7), EVP_PKEY-DH(7), EVP_PKEY-RSA(7), EVP_PKEY-EC(7) and
       EVP_PKEY-X25519(7).  The 'quick' one-shot function EVP_PKEY_Q_keygen(3) and macros for the
       most common cases: <EVP_RSA_gen(3)> and EVP_EC_gen(3) may also be used.

       Deprecated low-level key reading and writing functions

       Use of low-level objects (such as DSA) has been informally discouraged from use for a long
       time. Functions to read and write these low-level objects (such as PEM_read_DSA_PUBKEY())
       should be replaced. Applications should instead use OSSL_ENCODER_to_bio(3) and

       Deprecated low-level key printing functions

       Use of low-level objects (such as DSA) has been informally discouraged from use for a long
       time. Functions to print these low-level objects such as DSA_print() should be replaced
       with the equivalent EVP_PKEY functions.  Application should use one of
       EVP_PKEY_print_public(3), EVP_PKEY_print_private(3), EVP_PKEY_print_params(3),
       EVP_PKEY_print_public_fp(3), EVP_PKEY_print_private_fp(3) or EVP_PKEY_print_params_fp(3).
       Note that internally these use OSSL_ENCODER_to_bio(3) and OSSL_DECODER_from_bio(3).

       Deprecated function mappings

       The following functions have been deprecated in 3.0.

       •   AES_bi_ige_encrypt() and AES_ige_encrypt()

           There is no replacement for the IGE functions. New code should not use these modes.
           These undocumented functions were never integrated into the EVP layer.  They
           implemented the AES Infinite Garble Extension (IGE) mode and AES Bi-directional IGE
           mode. These modes were never formally standardised and usage of these functions is
           believed to be very small. In particular AES_bi_ige_encrypt() has a known bug. It
           accepts 2 AES keys, but only one is ever used. The security implications are believed
           to be minimal, but this issue was never fixed for backwards compatibility reasons.

       •   AES_encrypt(), AES_decrypt(), AES_set_encrypt_key(), AES_set_decrypt_key(),
           AES_cbc_encrypt(), AES_cfb128_encrypt(), AES_cfb1_encrypt(), AES_cfb8_encrypt(),
           AES_ecb_encrypt(), AES_ofb128_encrypt()AES_unwrap_key(), AES_wrap_key()

           See "Deprecated low-level encryption functions"

       •   AES_options()

           There is no replacement. It returned a string indicating if the AES code was unrolled.

       •   ASN1_digest(), ASN1_sign(), ASN1_verify()

           There are no replacements. These old functions are not used, and could be disabled
           with the macro NO_ASN1_OLD since OpenSSL 0.9.7.

       •   ASN1_STRING_length_set()

           Use ASN1_STRING_set(3) or ASN1_STRING_set0(3) instead.  This was a potentially unsafe
           function that could change the bounds of a previously passed in pointer.

       •   BF_encrypt(), BF_decrypt(), BF_set_key(), BF_cbc_encrypt(), BF_cfb64_encrypt(),
           BF_ecb_encrypt(), BF_ofb64_encrypt()

           See "Deprecated low-level encryption functions".  The Blowfish algorithm has been
           moved to the Legacy Provider.

       •   BF_options()

           There is no replacement. This option returned a constant string.

       •   BIO_get_callback(), BIO_set_callback(), BIO_debug_callback()

           Use the respective non-deprecated _ex() functions.

       •   BN_is_prime_ex(), BN_is_prime_fasttest_ex()

           Use BN_check_prime(3) which that avoids possible misuse and always uses at least 64
           rounds of the Miller-Rabin primality test.

       •   BN_pseudo_rand(), BN_pseudo_rand_range()

           Use BN_rand(3) and BN_rand_range(3).

       •   BN_X931_derive_prime_ex(), BN_X931_generate_prime_ex(), BN_X931_generate_Xpq()

           There are no replacements for these low-level functions. They were used internally by
           RSA_X931_derive_ex() and RSA_X931_generate_key_ex() which are also deprecated.  Use
           EVP_PKEY_keygen(3) instead.

       •   Camellia_encrypt(), Camellia_decrypt(), Camellia_set_key(), Camellia_cbc_encrypt(),
           Camellia_cfb128_encrypt(), Camellia_cfb1_encrypt(), Camellia_cfb8_encrypt(),
           Camellia_ctr128_encrypt(), Camellia_ecb_encrypt(), Camellia_ofb128_encrypt()

           See "Deprecated low-level encryption functions".

       •   CAST_encrypt(), CAST_decrypt(), CAST_set_key(), CAST_cbc_encrypt(),
           CAST_cfb64_encrypt(), CAST_ecb_encrypt(), CAST_ofb64_encrypt()

           See "Deprecated low-level encryption functions".  The CAST algorithm has been moved to
           the Legacy Provider.

       •   CMAC_CTX_new(), CMAC_CTX_cleanup(), CMAC_CTX_copy(), CMAC_CTX_free(),

           See "Deprecated low-level MAC functions".

       •   CMAC_Init(), CMAC_Update(), CMAC_Final(), CMAC_resume()

           See "Deprecated low-level MAC functions".

       •   CRYPTO_mem_ctrl(), CRYPTO_mem_debug_free(), CRYPTO_mem_debug_malloc(),
           CRYPTO_mem_debug_pop(), CRYPTO_mem_debug_push(), CRYPTO_mem_debug_realloc(),
           CRYPTO_mem_leaks(), CRYPTO_mem_leaks_cb(), CRYPTO_mem_leaks_fp(),

           Memory-leak checking has been deprecated in favor of more modern development tools,
           such as compiler memory and leak sanitizers or Valgrind.

       •   CRYPTO_cts128_encrypt_block(), CRYPTO_cts128_encrypt(), CRYPTO_cts128_decrypt_block(),
           CRYPTO_cts128_decrypt(), CRYPTO_nistcts128_encrypt_block(),
           CRYPTO_nistcts128_encrypt(), CRYPTO_nistcts128_decrypt_block(),

           Use the higher level functions EVP_CipherInit_ex2(), EVP_CipherUpdate() and
           EVP_CipherFinal_ex() instead.  See the "cts_mode" parameter in "Gettable and Settable
           EVP_CIPHER_CTX parameters" in EVP_EncryptInit(3).  See "EXAMPLES" in
           EVP_EncryptInit(3) for a AES-256-CBC-CTS example.

       •   d2i_DHparams(), d2i_DHxparams(), d2i_DSAparams(), d2i_DSAPrivateKey(),
           d2i_DSAPrivateKey_bio(), d2i_DSAPrivateKey_fp(), d2i_DSA_PUBKEY(),
           d2i_DSA_PUBKEY_bio(), d2i_DSA_PUBKEY_fp(), d2i_DSAPublicKey(), d2i_ECParameters(),
           d2i_ECPrivateKey(), d2i_ECPrivateKey_bio(), d2i_ECPrivateKey_fp(), d2i_EC_PUBKEY(),
           d2i_EC_PUBKEY_bio(), d2i_EC_PUBKEY_fp(), o2i_ECPublicKey(), d2i_RSAPrivateKey(),
           d2i_RSAPrivateKey_bio(), d2i_RSAPrivateKey_fp(), d2i_RSA_PUBKEY(),
           d2i_RSA_PUBKEY_bio(), d2i_RSA_PUBKEY_fp(), d2i_RSAPublicKey(), d2i_RSAPublicKey_bio(),

           See "Deprecated i2d and d2i functions for low-level key types"

       •   DES_crypt(), DES_fcrypt(), DES_encrypt1(), DES_encrypt2(), DES_encrypt3(),
           DES_decrypt3(), DES_ede3_cbc_encrypt(), DES_ede3_cfb64_encrypt(),
           DES_ede3_cfb_encrypt(),DES_ede3_ofb64_encrypt(), DES_ecb_encrypt(),
           DES_ecb3_encrypt(), DES_ofb64_encrypt(), DES_ofb_encrypt(), DES_cfb64_encrypt
           DES_cfb_encrypt(), DES_cbc_encrypt(), DES_ncbc_encrypt(), DES_pcbc_encrypt(),
           DES_xcbc_encrypt(), DES_cbc_cksum(), DES_quad_cksum(), DES_check_key_parity(),
           DES_is_weak_key(), DES_key_sched(), DES_options(), DES_random_key(), DES_set_key(),
           DES_set_key_checked(), DES_set_key_unchecked(), DES_set_odd_parity(),
           DES_string_to_2keys(), DES_string_to_key()

           See "Deprecated low-level encryption functions".  Algorithms for "DESX-CBC", "DES-
           ECB", "DES-CBC", "DES-OFB", "DES-CFB", "DES-CFB1" and "DES-CFB8" have been moved to
           the Legacy Provider.

       •   DH_bits(), DH_security_bits(), DH_size()

           Use EVP_PKEY_get_bits(3), EVP_PKEY_get_security_bits(3) and EVP_PKEY_get_size(3).

       •   DH_check(), DH_check_ex(), DH_check_params(), DH_check_params_ex(),
           DH_check_pub_key(), DH_check_pub_key_ex()

           See "Deprecated low-level validation functions"

       •   DH_clear_flags(), DH_test_flags(), DH_set_flags()

           The DH_FLAG_CACHE_MONT_P flag has been deprecated without replacement.  The
           DH_FLAG_TYPE_DH and DH_FLAG_TYPE_DHX have been deprecated.  Use EVP_PKEY_is_a() to
           determine the type of a key.  There is no replacement for setting these flags.

       •   DH_compute_key() DH_compute_key_padded()

           See "Deprecated low-level key exchange functions".

       •   DH_new(), DH_new_by_nid(), DH_free(), DH_up_ref()

           See "Deprecated low-level object creation"

       •   DH_generate_key(), DH_generate_parameters_ex()

           See "Deprecated low-level key generation functions".

       •   DH_get0_pqg(), DH_get0_p(), DH_get0_q(), DH_get0_g(), DH_get0_key(),
           DH_get0_priv_key(), DH_get0_pub_key(), DH_get_length(), DH_get_nid()

           See "Deprecated low-level key parameter getters"

       •   DH_get_1024_160(), DH_get_2048_224(), DH_get_2048_256()

           Applications should instead set the OSSL_PKEY_PARAM_GROUP_NAME as specified in "DH
           parameters" in EVP_PKEY-DH(7)) to one of "dh_1024_160", "dh_2048_224" or "dh_2048_256"
           when generating a DH key.

       •   DH_KDF_X9_42()

           Applications should use EVP_PKEY_CTX_set_dh_kdf_type(3) instead.

       •   DH_get_default_method(), DH_get0_engine(), DH_meth_*(), DH_new_method(), DH_OpenSSL(),
           DH_get_ex_data(), DH_set_default_method(), DH_set_method(), DH_set_ex_data()

           See "Providers are a replacement for engines and low-level method overrides"

       •   DHparams_print(), DHparams_print_fp()

           See "Deprecated low-level key printing functions"

       •   DH_set0_key(), DH_set0_pqg(), DH_set_length()

           See "Deprecated low-level key parameter setters"

       •   DSA_bits(), DSA_security_bits(), DSA_size()

           Use EVP_PKEY_get_bits(3), EVP_PKEY_get_security_bits(3) and EVP_PKEY_get_size(3).

       •   DHparams_dup(), DSA_dup_DH()

           There is no direct replacement. Applications may use EVP_PKEY_copy_parameters(3) and
           EVP_PKEY_dup(3) instead.

       •   DSA_generate_key(), DSA_generate_parameters_ex()

           See "Deprecated low-level key generation functions".

       •   DSA_get0_engine(), DSA_get_default_method(), DSA_get_ex_data(), DSA_get_method(),
           DSA_meth_*(), DSA_new_method(), DSA_OpenSSL(), DSA_set_default_method(),
           DSA_set_ex_data(), DSA_set_method()

           See "Providers are a replacement for engines and low-level method overrides".

       •   DSA_get0_p(), DSA_get0_q(), DSA_get0_g(), DSA_get0_pqg(), DSA_get0_key(),
           DSA_get0_priv_key(), DSA_get0_pub_key()

           See "Deprecated low-level key parameter getters".

       •   DSA_new(), DSA_free(), DSA_up_ref()

           See "Deprecated low-level object creation"

       •   DSAparams_dup()

           There is no direct replacement. Applications may use EVP_PKEY_copy_parameters(3) and
           EVP_PKEY_dup(3) instead.

       •   DSAparams_print(), DSAparams_print_fp(), DSA_print(), DSA_print_fp()

           See "Deprecated low-level key printing functions"

       •   DSA_set0_key(), DSA_set0_pqg()

           See "Deprecated low-level key parameter setters"

       •   DSA_set_flags(), DSA_clear_flags(), DSA_test_flags()

           The DSA_FLAG_CACHE_MONT_P flag has been deprecated without replacement.

       •   DSA_sign(), DSA_do_sign(), DSA_sign_setup(), DSA_verify(), DSA_do_verify()

           See "Deprecated low-level signing functions".

       •   ECDH_compute_key()

           See "Deprecated low-level key exchange functions".

       •   ECDH_KDF_X9_62()

           Applications may either set this using the helper function
           EVP_PKEY_CTX_set_ecdh_kdf_type(3) or by setting an OSSL_PARAM using the "kdf-type" as
           shown in "EXAMPLES" in EVP_KEYEXCH-ECDH(7)

       •   ECDSA_sign(), ECDSA_sign_ex(), ECDSA_sign_setup(), ECDSA_do_sign(),
           ECDSA_do_sign_ex(), ECDSA_verify(), ECDSA_do_verify()

           See "Deprecated low-level signing functions".

       •   ECDSA_size()

           Applications should use EVP_PKEY_get_size(3).

       •   EC_GF2m_simple_method(), EC_GFp_mont_method(), EC_GFp_nist_method(),
           EC_GFp_nistp224_method(), EC_GFp_nistp256_method(), EC_GFp_nistp521_method(),

           There are no replacements for these functions. Applications should rely on the library
           automatically assigning a suitable method internally when an EC_GROUP is constructed.

       •   EC_GROUP_clear_free()

           Use EC_GROUP_free(3) instead.

       •   EC_GROUP_get_curve_GF2m(), EC_GROUP_get_curve_GFp(), EC_GROUP_set_curve_GF2m(),

           Applications should use EC_GROUP_get_curve(3) and EC_GROUP_set_curve(3).

       •   EC_GROUP_have_precompute_mult(), EC_GROUP_precompute_mult(), EC_KEY_precompute_mult()

           These functions are not widely used. Applications should instead switch to named
           curves which OpenSSL has hardcoded lookup tables for.

       •   EC_GROUP_new(), EC_GROUP_method_of(), EC_POINT_method_of()

           EC_METHOD is now an internal-only concept and a suitable EC_METHOD is assigned
           internally without application intervention.  Users of EC_GROUP_new() should switch to
           a different suitable constructor.

       •   EC_KEY_can_sign()

           Applications should use EVP_PKEY_can_sign(3) instead.

       •   EC_KEY_check_key()

           See "Deprecated low-level validation functions"

       •   EC_KEY_set_flags(), EC_KEY_get_flags(), EC_KEY_clear_flags()

           See "Common EC parameters" in EVP_PKEY-EC(7) which handles flags as seperate
           "EXAMPLES" in EVP_PKEY-EC(7)

       •   EC_KEY_dup(), EC_KEY_copy()

           There is no direct replacement. Applications may use EVP_PKEY_copy_parameters(3) and
           EVP_PKEY_dup(3) instead.

       •   EC_KEY_decoded_from_explicit_params()

           There is no replacement.

       •   EC_KEY_generate_key()

           See "Deprecated low-level key generation functions".

       •   EC_KEY_get0_group(), EC_KEY_get0_private_key(), EC_KEY_get0_public_key(),
           EC_KEY_get_conv_form(), EC_KEY_get_enc_flags()

           See "Deprecated low-level key parameter getters".

       •   EC_KEY_get0_engine(), EC_KEY_get_default_method(), EC_KEY_get_method(),
           EC_KEY_new_method(), EC_KEY_get_ex_data(), EC_KEY_OpenSSL(), EC_KEY_set_ex_data(),
           EC_KEY_set_default_method(), EC_KEY_METHOD_*(), EC_KEY_set_method()

           See "Providers are a replacement for engines and low-level method overrides"

       •   EC_METHOD_get_field_type()

           Use EC_GROUP_get_field_type(3) instead.  See "Providers are a replacement for engines
           and low-level method overrides"

       •   EC_KEY_key2buf(), EC_KEY_oct2key(), EC_KEY_oct2priv(), EC_KEY_priv2buf(),

           There are no replacements for these.

       •   EC_KEY_new(), EC_KEY_new_by_curve_name(), EC_KEY_free(), EC_KEY_up_ref()

           See "Deprecated low-level object creation"

       •   EC_KEY_print(), EC_KEY_print_fp()

           See "Deprecated low-level key printing functions"

       •   EC_KEY_set_asn1_flag(), EC_KEY_set_conv_form(), EC_KEY_set_enc_flags()

           See "Deprecated low-level key parameter setters".

       •   EC_KEY_set_group(), EC_KEY_set_private_key(), EC_KEY_set_public_key(),

           See "Deprecated low-level key parameter setters".

       •   ECParameters_print(), ECParameters_print_fp(), ECPKParameters_print(),

           See "Deprecated low-level key printing functions"

       •   EC_POINT_bn2point(), EC_POINT_point2bn()

           These functions were not particularly useful, since EC point serialization formats are
           not individual big-endian integers.

       •   EC_POINT_get_affine_coordinates_GF2m(), EC_POINT_get_affine_coordinates_GFp(),
           EC_POINT_set_affine_coordinates_GF2m(), EC_POINT_set_affine_coordinates_GFp()

           Applications should use EC_POINT_get_affine_coordinates(3) and
           EC_POINT_set_affine_coordinates(3) instead.

       •   EC_POINT_get_Jprojective_coordinates_GFp(), EC_POINT_set_Jprojective_coordinates_GFp()

           These functions are not widely used. Applications should instead use the
           EC_POINT_set_affine_coordinates(3) and EC_POINT_get_affine_coordinates(3) functions.

       •   EC_POINT_make_affine(), EC_POINTs_make_affine()

           There is no replacement. These functions were not widely used, and OpenSSL
           automatically performs this conversion when needed.

       •   EC_POINT_set_compressed_coordinates_GF2m(), EC_POINT_set_compressed_coordinates_GFp()

           Applications should use EC_POINT_set_compressed_coordinates(3) instead.

       •   EC_POINTs_mul()

           This function is not widely used. Applications should instead use the EC_POINT_mul(3)

       •   ENGINE_*()

           All engine functions are deprecated. An engine should be rewritten as a provider.  See
           "Providers are a replacement for engines and low-level method overrides".

       •   ERR_load_*(), ERR_func_error_string(), ERR_get_error_line(),
           ERR_get_error_line_data(), ERR_get_state()

           OpenSSL now loads error strings automatically so these functions are not needed.

       •   ERR_peek_error_line_data(), ERR_peek_last_error_line_data()

           The new functions are ERR_peek_error_func(3), ERR_peek_last_error_func(3),
           ERR_peek_error_data(3), ERR_peek_last_error_data(3), ERR_get_error_all(3),
           ERR_peek_error_all(3) and ERR_peek_last_error_all(3).  Applications should use
           ERR_get_error_all(3), or pick information with ERR_peek functions and finish off with
           getting the error code by using ERR_get_error(3).

       •   EVP_CIPHER_CTX_iv(), EVP_CIPHER_CTX_iv_noconst(), EVP_CIPHER_CTX_original_iv()

           Applications should instead use EVP_CIPHER_CTX_get_updated_iv(3),
           EVP_CIPHER_CTX_get_updated_iv(3) and EVP_CIPHER_CTX_get_original_iv(3) respectively.
           See EVP_CIPHER_CTX_get_original_iv(3) for further information.

       •   EVP_CIPHER_meth_*(), EVP_MD_CTX_set_update_fn(), EVP_MD_CTX_update_fn(),

           See "Providers are a replacement for engines and low-level method overrides".

           and EVP_PKEY_CTRL_CMS_SIGN()

           These control operations are not invoked by the OpenSSL library anymore and are
           replaced by direct checks of the key operation against the key type when the operation
           is initialized.

       •   EVP_PKEY_CTX_get0_dh_kdf_ukm(), EVP_PKEY_CTX_get0_ecdh_kdf_ukm()

           See the "kdf-ukm" item in "DH key exchange parameters" in EVP_KEYEXCH-DH(7) and "ECDH
           Key Exchange parameters" in EVP_KEYEXCH-ECDH(7).  These functions are obsolete and
           should not be required.

       •   EVP_PKEY_CTX_set_rsa_keygen_pubexp()

           Applications should use EVP_PKEY_CTX_set1_rsa_keygen_pubexp(3) instead.

       •   EVP_PKEY_cmp(), EVP_PKEY_cmp_parameters()

           Applications should use EVP_PKEY_eq(3) and EVP_PKEY_parameters_eq(3) instead.  See
           EVP_PKEY_copy_parameters(3) for further details.

       •   EVP_PKEY_encrypt_old(), EVP_PKEY_decrypt_old(),

           Applications should use EVP_PKEY_encrypt_init(3) and EVP_PKEY_encrypt(3) or
           EVP_PKEY_decrypt_init(3) and EVP_PKEY_decrypt(3) instead.

       •   EVP_PKEY_get0()

           This function returns NULL if the key comes from a provider.

       •   EVP_PKEY_get0_DH(), EVP_PKEY_get0_DSA(), EVP_PKEY_get0_EC_KEY(), EVP_PKEY_get0_RSA(),
           EVP_PKEY_get1_DH(), EVP_PKEY_get1_DSA(), EVP_PKEY_get1_EC_KEY and EVP_PKEY_get1_RSA(),
           EVP_PKEY_get0_hmac(), EVP_PKEY_get0_poly1305(), EVP_PKEY_get0_siphash()

           See "Functions that return an internal key should be treated as read only".

       •   EVP_PKEY_meth_*()

           See "Providers are a replacement for engines and low-level method overrides".

       •   EVP_PKEY_new_CMAC_key()

           See "Deprecated low-level MAC functions".

       •   EVP_PKEY_assign(), EVP_PKEY_set1_DH(), EVP_PKEY_set1_DSA(), EVP_PKEY_set1_EC_KEY(),

           See "Deprecated low-level key object getters and setters"

       •   EVP_PKEY_set1_tls_encodedpoint() EVP_PKEY_get1_tls_encodedpoint()

           These functions were previously used by libssl to set or get an encoded public key
           into/from an EVP_PKEY object. With OpenSSL 3.0 these are replaced by the more generic
           functions EVP_PKEY_set1_encoded_public_key(3) and EVP_PKEY_get1_encoded_public_key(3).
           The old versions have been converted to deprecated macros that just call the new

       •   EVP_PKEY_set1_engine(), EVP_PKEY_get0_engine()

           See "Providers are a replacement for engines and low-level method overrides".

       •   EVP_PKEY_set_alias_type()

           This function has been removed. There is no replacement.  See
           "EVP_PKEY_set_alias_type() method has been removed"

       •   HMAC_Init_ex(), HMAC_Update(), HMAC_Final(), HMAC_size()

           See "Deprecated low-level MAC functions".

       •   HMAC_CTX_new(), HMAC_CTX_free(), HMAC_CTX_copy(), HMAC_CTX_reset(),
           HMAC_CTX_set_flags(), HMAC_CTX_get_md()

           See "Deprecated low-level MAC functions".

       •   i2d_DHparams(), i2d_DHxparams()

           See "Deprecated low-level key reading and writing functions" and "Migration" in

       •   i2d_DSAparams(), i2d_DSAPrivateKey(), i2d_DSAPrivateKey_bio(), i2d_DSAPrivateKey_fp(),
           i2d_DSA_PUBKEY(), i2d_DSA_PUBKEY_bio(), i2d_DSA_PUBKEY_fp(), i2d_DSAPublicKey()

           See "Deprecated low-level key reading and writing functions" and "Migration" in

       •   i2d_ECParameters(), i2d_ECPrivateKey(), i2d_ECPrivateKey_bio(), i2d_ECPrivateKey_fp(),
           i2d_EC_PUBKEY(), i2d_EC_PUBKEY_bio(), i2d_EC_PUBKEY_fp(), i2o_ECPublicKey()

           See "Deprecated low-level key reading and writing functions" and "Migration" in

       •   i2d_RSAPrivateKey(), i2d_RSAPrivateKey_bio(), i2d_RSAPrivateKey_fp(),
           i2d_RSA_PUBKEY(), i2d_RSA_PUBKEY_bio(), i2d_RSA_PUBKEY_fp(), i2d_RSAPublicKey(),
           i2d_RSAPublicKey_bio(), i2d_RSAPublicKey_fp()

           See "Deprecated low-level key reading and writing functions" and "Migration" in

       •   IDEA_encrypt(), IDEA_set_decrypt_key(), IDEA_set_encrypt_key(), IDEA_cbc_encrypt(),
           IDEA_cfb64_encrypt(), IDEA_ecb_encrypt(), IDEA_ofb64_encrypt()

           See "Deprecated low-level encryption functions".  IDEA has been moved to the Legacy

       •   IDEA_options()

           There is no replacement. This function returned a constant string.

       •   MD2(), MD2_Init(), MD2_Update(), MD2_Final()

           See "Deprecated low-level encryption functions".  MD2 has been moved to the Legacy

       •   MD2_options()

           There is no replacement. This function returned a constant string.

       •   MD4(), MD4_Init(), MD4_Update(), MD4_Final(), MD4_Transform()

           See "Deprecated low-level encryption functions".  MD4 has been moved to the Legacy

       •   MDC2(), MDC2_Init(), MDC2_Update(), MDC2_Final()

           See "Deprecated low-level encryption functions".  MDC2 has been moved to the Legacy

       •   MD5(), MD5_Init(), MD5_Update(), MD5_Final(), MD5_Transform()

           See "Deprecated low-level encryption functions".

       •   NCONF_WIN32()

           This undocumented function has no replacement.  See "HISTORY" in config(5) for more

       •   OCSP_parse_url()

           Use OSSL_HTTP_parse_url(3) instead.

       •   OCSP_REQ_CTX type and OCSP_REQ_CTX_*() functions

           These methods were used to collect all necessary data to form a HTTP request, and to
           perform the HTTP transfer with that request.  With OpenSSL 3.0, the type is
           OSSL_HTTP_REQ_CTX, and the deprecated functions are replaced with
           OSSL_HTTP_REQ_CTX_*(). See OSSL_HTTP_REQ_CTX(3) for additional details.

       •   OPENSSL_fork_child(), OPENSSL_fork_parent(), OPENSSL_fork_prepare()

           There is no replacement for these functions. These pthread fork support methods were
           unused by OpenSSL.

       •   OSSL_STORE_ctrl(), OSSL_STORE_do_all_loaders(), OSSL_STORE_LOADER_get0_engine(),
           OSSL_STORE_LOADER_get0_scheme(), OSSL_STORE_LOADER_new(),
           OSSL_STORE_LOADER_set_attach(), OSSL_STORE_LOADER_set_close(),
           OSSL_STORE_LOADER_set_ctrl(), OSSL_STORE_LOADER_set_eof(),
           OSSL_STORE_LOADER_set_error(), OSSL_STORE_LOADER_set_expect(),
           OSSL_STORE_LOADER_set_find(), OSSL_STORE_LOADER_set_load(),
           OSSL_STORE_LOADER_set_open(), OSSL_STORE_LOADER_set_open_ex(),
           OSSL_STORE_register_loader(), OSSL_STORE_unregister_loader(), OSSL_STORE_vctrl()

           These functions helped applications and engines create loaders for schemes they
           supported.  These are all deprecated and discouraged in favour of provider
           implementations, see provider-storemgmt(7).

       •   PEM_read_DHparams(), PEM_read_bio_DHparams(), PEM_read_DSAparams(),
           PEM_read_bio_DSAparams(), PEM_read_DSAPrivateKey(), PEM_read_DSA_PUBKEY(),
           PEM_read_bio_DSAPrivateKey and PEM_read_bio_DSA_PUBKEY(), PEM_read_ECPKParameters(),
           PEM_read_ECPrivateKey(), PEM_read_EC_PUBKEY(), PEM_read_bio_ECPKParameters(),
           PEM_read_bio_ECPrivateKey(), PEM_read_bio_EC_PUBKEY(), PEM_read_RSAPrivateKey(),
           PEM_read_RSA_PUBKEY(), PEM_read_RSAPublicKey(), PEM_read_bio_RSAPrivateKey(),
           PEM_read_bio_RSA_PUBKEY(), PEM_read_bio_RSAPublicKey(), PEM_write_bio_DHparams(),
           PEM_write_bio_DHxparams(), PEM_write_DHparams(), PEM_write_DHxparams(),
           PEM_write_DSAparams(), PEM_write_DSAPrivateKey(), PEM_write_DSA_PUBKEY(),
           PEM_write_bio_DSAparams(), PEM_write_bio_DSAPrivateKey(), PEM_write_bio_DSA_PUBKEY(),
           PEM_write_ECPKParameters(), PEM_write_ECPrivateKey(), PEM_write_EC_PUBKEY(),
           PEM_write_bio_ECPKParameters(), PEM_write_bio_ECPrivateKey(),
           PEM_write_bio_EC_PUBKEY(), PEM_write_RSAPrivateKey(), PEM_write_RSA_PUBKEY(),
           PEM_write_RSAPublicKey(), PEM_write_bio_RSAPrivateKey(), PEM_write_bio_RSA_PUBKEY(),

           See "Deprecated low-level key reading and writing functions"

       •   PKCS1_MGF1()

           See "Deprecated low-level encryption functions".

       •   RAND_get_rand_method(), RAND_set_rand_method(), RAND_OpenSSL(), RAND_set_rand_engine()

           Applications should instead use RAND_set_DRBG_type(3), EVP_RAND(3) and EVP_RAND(7).
           See RAND_set_rand_method(3) for more details.

       •   RC2_encrypt(), RC2_decrypt(), RC2_set_key(), RC2_cbc_encrypt(), RC2_cfb64_encrypt(),
           RC2_ecb_encrypt(), RC2_ofb64_encrypt(), RC4(), RC4_set_key(), RC4_options(),
           RC5_32_encrypt(), RC5_32_set_key(), RC5_32_decrypt(), RC5_32_cbc_encrypt(),
           RC5_32_cfb64_encrypt(), RC5_32_ecb_encrypt(), RC5_32_ofb64_encrypt()

           See "Deprecated low-level encryption functions".  The Algorithms "RC2", "RC4" and
           "RC5" have been moved to the Legacy Provider.

       •   RIPEMD160(), RIPEMD160_Init(), RIPEMD160_Update(), RIPEMD160_Final(),

           See "Deprecated low-level digest functions".  The RIPE algorithm has been moved to the
           Legacy Provider.

       •   RSA_bits(), RSA_security_bits(), RSA_size()

           Use EVP_PKEY_get_bits(3), EVP_PKEY_get_security_bits(3) and EVP_PKEY_get_size(3).

       •   RSA_check_key(), RSA_check_key_ex()

           See "Deprecated low-level validation functions"

       •   RSA_clear_flags(), RSA_flags(), RSA_set_flags(), RSA_test_flags(),
           RSA_setup_blinding(), RSA_blinding_off(), RSA_blinding_on()

           All of these RSA flags have been deprecated without replacement:

           RSA_FLAG_NO_BLINDING, RSA_FLAG_THREAD_SAFE RSA_METHOD_FLAG_NO_CHECKRSA_generate_key_ex(), RSA_generate_multi_prime_key()

           See "Deprecated low-level key generation functions".

       •   RSA_get0_engine()

           See "Providers are a replacement for engines and low-level method overrides"

       •   RSA_get0_crt_params(), RSA_get0_d(), RSA_get0_dmp1(), RSA_get0_dmq1(), RSA_get0_e(),
           RSA_get0_factors(), RSA_get0_iqmp(), RSA_get0_key(),
           RSA_get0_multi_prime_crt_params(), RSA_get0_multi_prime_factors(), RSA_get0_n(),
           RSA_get0_p(), RSA_get0_pss_params(), RSA_get0_q(), RSA_get_multi_prime_extra_count()

           See "Deprecated low-level key parameter getters"

       •   RSA_new(), RSA_free(), RSA_up_ref()

           See "Deprecated low-level object creation".

       •   RSA_get_default_method(), RSA_get_ex_data and RSA_get_method()

           See "Providers are a replacement for engines and low-level method overrides".

       •   RSA_get_version()

           There is no replacement.

       •   RSA_meth_*(), RSA_new_method(), RSA_null_method and RSA_PKCS1_OpenSSL()

           See "Providers are a replacement for engines and low-level method overrides".

       •   RSA_padding_add_*(), RSA_padding_check_*()

           See "Deprecated low-level signing functions" and "Deprecated low-level encryption

       •   RSA_print(), RSA_print_fp()

           See "Deprecated low-level key printing functions"

       •   RSA_public_encrypt(), RSA_private_decrypt()

           See "Deprecated low-level encryption functions"

       •   RSA_private_encrypt(), RSA_public_decrypt()

           This is equivalent to doing sign and verify recover operations (with a padding mode of
           none). See "Deprecated low-level signing functions".

       •   RSAPrivateKey_dup(), RSAPublicKey_dup()

           There is no direct replacement. Applications may use EVP_PKEY_dup(3).

       •   RSAPublicKey_it(), RSAPrivateKey_it()

           See "Deprecated low-level key reading and writing functions"

       •   RSA_set0_crt_params(), RSA_set0_factors(), RSA_set0_key(),

           See "Deprecated low-level key parameter setters".

       •   RSA_set_default_method(), RSA_set_method(), RSA_set_ex_data()

           See "Providers are a replacement for engines and low-level method overrides"

       •   RSA_sign(), RSA_sign_ASN1_OCTET_STRING(), RSA_verify(),
           RSA_verify_ASN1_OCTET_STRING(), RSA_verify_PKCS1_PSS(), RSA_verify_PKCS1_PSS_mgf1()

           See "Deprecated low-level signing functions".

       •   RSA_X931_derive_ex(), RSA_X931_generate_key_ex(), RSA_X931_hash_id()

           There are no replacements for these functions.  X931 padding can be set using
           "Signature Parameters" in EVP_SIGNATURE-RSA(7).  See OSSL_SIGNATURE_PARAM_PAD_MODE.

       •   SEED_encrypt(), SEED_decrypt(), SEED_set_key(), SEED_cbc_encrypt(),
           SEED_cfb128_encrypt(), SEED_ecb_encrypt(), SEED_ofb128_encrypt()

           See "Deprecated low-level encryption functions".  The SEED algorithm has been moved to
           the Legacy Provider.

       •   SHA1_Init(), SHA1_Update(), SHA1_Final(), SHA1_Transform(), SHA224_Init(),
           SHA224_Update(), SHA224_Final(), SHA256_Init(), SHA256_Update(), SHA256_Final(),
           SHA256_Transform(), SHA384_Init(), SHA384_Update(), SHA384_Final(), SHA512_Init(),
           SHA512_Update(), SHA512_Final(), SHA512_Transform()

           See "Deprecated low-level digest functions".

       •   SRP_Calc_A(), SRP_Calc_B(), SRP_Calc_client_key(), SRP_Calc_server_key(),
           SRP_Calc_u(), SRP_Calc_x(), SRP_check_known_gN_param(), SRP_create_verifier(),
           SRP_create_verifier_BN(), SRP_get_default_gN(), SRP_user_pwd_free(),
           SRP_user_pwd_new(), SRP_user_pwd_set0_sv(), SRP_user_pwd_set1_ids(),
           SRP_user_pwd_set_gN(), SRP_VBASE_add0_user(), SRP_VBASE_free(),
           SRP_VBASE_get1_by_user(), SRP_VBASE_init(), SRP_VBASE_new(), SRP_Verify_A_mod_N(),

           There are no replacements for the SRP functions.

       •   SSL_CTX_set_tmp_dh_callback(), SSL_set_tmp_dh_callback(), SSL_CTX_set_tmp_dh(),

           These are used to set the Diffie-Hellman (DH) parameters that are to be used by
           servers requiring ephemeral DH keys. Instead applications should consider using the
           built-in DH parameters that are available by calling SSL_CTX_set_dh_auto(3) or
           SSL_set_dh_auto(3). If custom parameters are necessary then applications can use the
           alternative functions SSL_CTX_set0_tmp_dh_pkey(3) and SSL_set0_tmp_dh_pkey(3). There
           is no direct replacement for the "callback" functions. The callback was originally
           useful in order to have different parameters for export and non-export ciphersuites.
           Export ciphersuites are no longer supported by OpenSSL. Use of the callback functions
           should be replaced by one of the other methods described above.

       •   SSL_CTX_set_tlsext_ticket_key_cb()

           Use the new SSL_CTX_set_tlsext_ticket_key_evp_cb(3) function instead.

       •   WHIRLPOOL(), WHIRLPOOL_Init(), WHIRLPOOL_Update(), WHIRLPOOL_Final(),

           See "Deprecated low-level digest functions".  The Whirlpool algorithm has been moved
           to the Legacy Provider.

       •   X509_certificate_type()

           This was an undocumented function. Applications can use X509_get0_pubkey(3) and
           X509_get0_signature(3) instead.

       •   X509_http_nbio(), X509_CRL_http_nbio()

           Use X509_load_http(3) and X509_CRL_load_http(3) instead.

   Using the FIPS Module in applications
       See fips_module(7) and OSSL_PROVIDER-FIPS(7) for details.

   OpenSSL command line application changes
       New applications

       openssl kdf uses the new EVP_KDF(3) API.  openssl kdf uses the new EVP_MAC(3) API.

       Added options

       -provider_path and -provider are available to all apps and can be used multiple times to
       load any providers, such as the 'legacy' provider or third party providers. If used then
       the 'default' provider would also need to be specified if required. The -provider_path
       must be specified before the -provider option.

       The list app has many new options. See openssl-list(1) for more information.

       -crl_lastupdate and -crl_nextupdate used by openssl ca allows explicit setting of fields
       in the generated CRL.

       Removed options

       Interactive mode is not longer available.

       The -crypt option used by openssl passwd.  The -c option used by openssl x509, openssl
       dhparam, openssl dsaparam, and openssl ecparam.

       Other Changes

       The output of Command line applications may have minor changes.  These are primarily
       changes in capitalisation and white space.  However, in some cases, there are additional
       differences.  For example, the DH parameters output from openssl dhparam now lists 'P',
       'Q', 'G' and 'pcounter' instead of 'prime', 'generator', 'subgroup order' and 'counter'

       The openssl commands that read keys, certificates, and CRLs now automatically detect the
       PEM or DER format of the input files so it is not necessary to explicitly specify the
       input format anymore. However if the input format option is used the specified format will
       be required.

       openssl speed no longer uses low-level API calls.  This implies some of the performance
       numbers might not be comparable with the previous releases due to higher overhead. This
       applies particularly to measuring performance on smaller data chunks.

       b<openssl dhparam>, openssl dsa, openssl gendsa, openssl dsaparam, openssl genrsa and
       openssl rsa have been modified to use PKEY APIs.  openssl genrsa and openssl rsa now write
       PKCS #8 keys by default.

       Default settings

       "SHA256" is now the default digest for TS query used by openssl ts.

       Deprecated apps

       openssl rsautl is deprecated, use openssl pkeyutl instead.  openssl dhparam, openssl dsa,
       openssl gendsa, openssl dsaparam, openssl genrsa, openssl rsa, openssl genrsa and openssl
       rsa are now in maintenance mode and no new features will be added to them.

   TLS Changes
       •   TLS 1.3 FFDHE key exchange support added

           This uses DH safe prime named groups.

       •   Support for fully "pluggable" TLSv1.3 groups.

           This means that providers may supply their own group implementations (using either the
           "key exchange" or the "key encapsulation" methods) which will automatically be
           detected and used by libssl.

       •   SSL and SSL_CTX options are now 64 bit instead of 32 bit.

           The signatures of the functions to get and set options on SSL and SSL_CTX objects
           changed from "unsigned long" to "uint64_t" type.

           This may require source code changes. For example it is no longer possible to use the
           SSL_OP_ macro values in preprocessor "#if" conditions.  However it is still possible
           to test whether these macros are defined or not.

           See SSL_CTX_get_options(3), SSL_CTX_set_options(3), SSL_get_options(3) and

       •   SSL_set1_host() and SSL_add1_host() Changes

           These functions now take IP literal addresses as well as actual hostnames.

       •   Added SSL option SSL_OP_CLEANSE_PLAINTEXT

           If the option is set, openssl cleanses (zeroizes) plaintext bytes from internal
           buffers after delivering them to the application. Note, the application is still
           responsible for cleansing other copies (e.g.: data received by SSL_read(3)).

       •   Client-initiated renegotiation is disabled by default.

           To allow it, use the -client_renegotiation option, the
           SSL_OP_ALLOW_CLIENT_RENEGOTIATION flag, or the "ClientRenegotiation" config parameter
           as appropriate.

       •   Secure renegotiation is now required by default for TLS connections

           Support for RFC 5746 secure renegotiation is now required by default for SSL or TLS
           connections to succeed.  Applications that require the ability to connect to legacy
           peers will need to explicitly set SSL_OP_LEGACY_SERVER_CONNECT.  Accordingly,
           SSL_OP_LEGACY_SERVER_CONNECT is no longer set as part of SSL_OP_ALL.

       •   Combining the Configure options no-ec and no-dh no longer disables TLSv1.3

           Typically if OpenSSL has no EC or DH algorithms then it cannot support connections
           with TLSv1.3. However OpenSSL now supports "pluggable" groups through providers.
           Therefore third party providers may supply group implementations even where there are
           no built-in ones. Attempting to create TLS connections in such a build without also
           disabling TLSv1.3 at run time or using third party provider groups may result in
           handshake failures. TLSv1.3 can be disabled at compile time using the "no-tls1_3"
           Configure option.

       •   SSL_CTX_set_ciphersuites() and SSL_set_ciphersuites() changes.

           The methods now ignore unknown ciphers.

       •   Security callback change.

           The security callback, which can be customised by application code, supports the
           security operation SSL_SECOP_TMP_DH. This is defined to take an EVP_PKEY in the
           "other" parameter. In most places this is what is passed. All these places occur
           server side. However there was one client side call of this security operation and it
           passed a DH object instead. This is incorrect according to the definition of
           SSL_SECOP_TMP_DH, and is inconsistent with all of the other locations. Therefore this
           client side call has been changed to pass an EVP_PKEY instead.


           The SSL option SSL_OP_IGNORE_UNEXPECTED_EOF is introduced. If that option is set, an
           unexpected EOF is ignored, it pretends a close notify was received instead and so the
           returned error becomes SSL_ERROR_ZERO_RETURN.

       •   The security strength of SHA1 and MD5 based signatures in TLS has been reduced.

           This results in SSL 3, TLS 1.0, TLS 1.1 and DTLS 1.0 no longer working at the default
           security level of 1 and instead requires security level 0. The security level can be
           changed either using the cipher string with @SECLEVEL, or calling
           SSL_CTX_set_security_level(3). This also means that where the signature algorithms
           extension is missing from a ClientHello then the handshake will fail in TLS 1.2 at
           security level 1. This is because, although this extension is optional, failing to
           provide one means that OpenSSL will fallback to a default set of signature algorithms.
           This default set requires the availability of SHA1.

       •   X509 certificates signed using SHA1 are no longer allowed at security level 1 and

           In TLS/SSL the default security level is 1. It can be set either using the cipher
           string with @SECLEVEL, or calling SSL_CTX_set_security_level(3). If the leaf
           certificate is signed with SHA-1, a call to SSL_CTX_use_certificate(3) will fail if
           the security level is not lowered first.  Outside TLS/SSL, the default security level
           is -1 (effectively 0). It can be set using X509_VERIFY_PARAM_set_auth_level(3) or
           using the -auth_level options of the commands.




       Copyright 2021 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the Apache License 2.0 (the "License").  You may not use this file except
       in compliance with the License.  You can obtain a copy in the file LICENSE in the source
       distribution or at <>.