openssl-prebuild/linux_amd64/ssl/share/man/man7/provider-cipher.7
2020-03-02 16:50:34 +00:00

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.\" ========================================================================
.\"
.IX Title "PROVIDER-CIPHER 7"
.TH PROVIDER-CIPHER 7 "2020-03-02" "3.0.0-dev" "OpenSSL"
.\" For nroff, turn off justification. Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.if n .ad l
.nh
.SH "NAME"
provider\-cipher \- The cipher library <\-> provider functions
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 2
\& #include <openssl/core_numbers.h>
\& #include <openssl/core_names.h>
\&
\& /*
\& * None of these are actual functions, but are displayed like this for
\& * the function signatures for functions that are offered as function
\& * pointers in OSSL_DISPATCH arrays.
\& */
\&
\& /* Context management */
\& void *OP_cipher_newctx(void *provctx);
\& void OP_cipher_freectx(void *cctx);
\& void *OP_cipher_dupctx(void *cctx);
\&
\& /* Encryption/decryption */
\& int OP_cipher_encrypt_init(void *cctx, const unsigned char *key,
\& size_t keylen, const unsigned char *iv,
\& size_t ivlen);
\& int OP_cipher_decrypt_init(void *cctx, const unsigned char *key,
\& size_t keylen, const unsigned char *iv,
\& size_t ivlen);
\& int OP_cipher_update(void *cctx, unsigned char *out, size_t *outl,
\& size_t outsize, const unsigned char *in, size_t inl);
\& int OP_cipher_final(void *cctx, unsigned char *out, size_t *outl,
\& size_t outsize);
\& int OP_cipher_cipher(void *cctx, unsigned char *out, size_t *outl,
\& size_t outsize, const unsigned char *in, size_t inl);
\&
\& /* Cipher parameter descriptors */
\& const OSSL_PARAM *OP_cipher_gettable_params(void);
\&
\& /* Cipher operation parameter descriptors */
\& const OSSL_PARAM *OP_cipher_gettable_ctx_params(void);
\& const OSSL_PARAM *OP_cipher_settable_ctx_params(void);
\&
\& /* Cipher parameters */
\& int OP_cipher_get_params(OSSL_PARAM params[]);
\&
\& /* Cipher operation parameters */
\& int OP_cipher_get_ctx_params(void *cctx, OSSL_PARAM params[]);
\& int OP_cipher_set_ctx_params(void *cctx, const OSSL_PARAM params[]);
.Ve
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
This documentation is primarily aimed at provider authors. See \fIprovider\fR\|(7)
for further information.
.PP
The \s-1CIPHER\s0 operation enables providers to implement cipher algorithms and make
them available to applications via the \s-1API\s0 functions \fIEVP_EncryptInit_ex\fR\|(3),
\&\fIEVP_EncryptUpdate\fR\|(3) and \fIEVP_EncryptFinal\fR\|(3) (as well as the decrypt
equivalents and other related functions).
.PP
All \*(L"functions\*(R" mentioned here are passed as function pointers between
\&\fIlibcrypto\fR and the provider in \fB\s-1OSSL_DISPATCH\s0\fR arrays via
\&\fB\s-1OSSL_ALGORITHM\s0\fR arrays that are returned by the provider's
\&\fIprovider_query_operation()\fR function
(see \*(L"Provider Functions\*(R" in \fIprovider\-base\fR\|(7)).
.PP
All these \*(L"functions\*(R" have a corresponding function type definition
named \fBOSSL_{name}_fn\fR, and a helper function to retrieve the
function pointer from an \fB\s-1OSSL_DISPATCH\s0\fR element named
\&\fBOSSL_get_{name}\fR.
For example, the \*(L"function\*(R" \fIOP_cipher_newctx()\fR has these:
.PP
.Vb 3
\& typedef void *(OSSL_OP_cipher_newctx_fn)(void *provctx);
\& static ossl_inline OSSL_OP_cipher_newctx_fn
\& OSSL_get_OP_cipher_newctx(const OSSL_DISPATCH *opf);
.Ve
.PP
\&\fB\s-1OSSL_DISPATCH\s0\fR arrays are indexed by numbers that are provided as
macros in \fIopenssl\-core_numbers.h\fR\|(7), as follows:
.PP
.Vb 3
\& OP_cipher_newctx OSSL_FUNC_CIPHER_NEWCTX
\& OP_cipher_freectx OSSL_FUNC_CIPHER_FREECTX
\& OP_cipher_dupctx OSSL_FUNC_CIPHER_DUPCTX
\&
\& OP_cipher_encrypt_init OSSL_FUNC_CIPHER_ENCRYPT_INIT
\& OP_cipher_decrypt_init OSSL_FUNC_CIPHER_DECRYPT_INIT
\& OP_cipher_update OSSL_FUNC_CIPHER_UPDATE
\& OP_cipher_final OSSL_FUNC_CIPHER_FINAL
\& OP_cipher_cipher OSSL_FUNC_CIPHER_CIPHER
\&
\& OP_cipher_get_params OSSL_FUNC_CIPHER_GET_PARAMS
\& OP_cipher_get_ctx_params OSSL_FUNC_CIPHER_GET_CTX_PARAMS
\& OP_cipher_set_ctx_params OSSL_FUNC_CIPHER_SET_CTX_PARAMS
\&
\& OP_cipher_gettable_params OSSL_FUNC_CIPHER_GETTABLE_PARAMS
\& OP_cipher_gettable_ctx_params OSSL_FUNC_CIPHER_GETTABLE_CTX_PARAMS
\& OP_cipher_settable_ctx_params OSSL_FUNC_CIPHER_SETTABLE_CTX_PARAMS
.Ve
.PP
A cipher algorithm implementation may not implement all of these functions.
In order to be a consistent set of functions there must at least be a complete
set of \*(L"encrypt\*(R" functions, or a complete set of \*(L"decrypt\*(R" functions, or a
single \*(L"cipher\*(R" function.
In all cases both the OP_cipher_newctx and OP_cipher_freectx functions must be
present.
All other functions are optional.
.SS "Context Management Functions"
.IX Subsection "Context Management Functions"
\&\fIOP_cipher_newctx()\fR should create and return a pointer to a provider side
structure for holding context information during a cipher operation.
A pointer to this context will be passed back in a number of the other cipher
operation function calls.
The parameter \fIprovctx\fR is the provider context generated during provider
initialisation (see \fIprovider\fR\|(7)).
.PP
\&\fIOP_cipher_freectx()\fR is passed a pointer to the provider side cipher context in
the \fIcctx\fR parameter.
This function should free any resources associated with that context.
.PP
\&\fIOP_cipher_dupctx()\fR should duplicate the provider side cipher context in the
\&\fIcctx\fR parameter and return the duplicate copy.
.SS "Encryption/Decryption Functions"
.IX Subsection "Encryption/Decryption Functions"
\&\fIOP_cipher_encrypt_init()\fR initialises a cipher operation for encryption given a
newly created provider side cipher context in the \fIcctx\fR parameter.
The key to be used is given in \fIkey\fR which is \fIkeylen\fR bytes long.
The \s-1IV\s0 to be used is given in \fIiv\fR which is \fIivlen\fR bytes long.
.PP
\&\fIOP_cipher_decrypt_init()\fR is the same as \fIOP_cipher_encrypt_init()\fR except that it
initialises the context for a decryption operation.
.PP
\&\fIOP_cipher_update()\fR is called to supply data to be encrypted/decrypted as part of
a previously initialised cipher operation.
The \fIcctx\fR parameter contains a pointer to a previously initialised provider
side context.
\&\fIOP_cipher_update()\fR should encrypt/decrypt \fIinl\fR bytes of data at the location
pointed to by \fIin\fR.
The encrypted data should be stored in \fIout\fR and the amount of data written to
\&\fI*outl\fR which should not exceed \fIoutsize\fR bytes.
\&\fIOP_cipher_update()\fR may be called multiple times for a single cipher operation.
It is the responsibility of the cipher implementation to handle input lengths
that are not multiples of the block length.
In such cases a cipher implementation will typically cache partial blocks of
input data until a complete block is obtained.
\&\fIout\fR may be the same location as \fIin\fR but it should not partially overlap.
The same expectations apply to \fIoutsize\fR as documented for
\&\fIEVP_EncryptUpdate\fR\|(3) and \fIEVP_DecryptUpdate\fR\|(3).
.PP
\&\fIOP_cipher_final()\fR completes an encryption or decryption started through previous
\&\fIOP_cipher_encrypt_init()\fR or \fIOP_cipher_decrypt_init()\fR, and \fIOP_cipher_update()\fR
calls.
The \fIcctx\fR parameter contains a pointer to the provider side context.
Any final encryption/decryption output should be written to \fIout\fR and the
amount of data written to \fI*outl\fR which should not exceed \fIoutsize\fR bytes.
The same expectations apply to \fIoutsize\fR as documented for
\&\fIEVP_EncryptFinal\fR\|(3) and \fIEVP_DecryptFinal\fR\|(3).
.PP
\&\fIOP_cipher_cipher()\fR performs encryption/decryption using the provider side cipher
context in the \fIcctx\fR parameter that should have been previously initialised via
a call to \fIOP_cipher_encrypt_init()\fR or \fIOP_cipher_decrypt_init()\fR.
This should call the raw underlying cipher function without any padding.
This will be invoked in the provider as a result of the application calling
\&\fIEVP_Cipher\fR\|(3).
The application is responsible for ensuring that the input is a multiple of the
block length.
The data to be encrypted/decrypted will be in \fIin\fR, and it will be \fIinl\fR bytes
in length.
The output from the encryption/decryption should be stored in \fIout\fR and the
amount of data stored should be put in \fI*outl\fR which should be no more than
\&\fIoutsize\fR bytes.
.SS "Cipher Parameters"
.IX Subsection "Cipher Parameters"
See \s-1\fIOSSL_PARAM\s0\fR\|(3) for further details on the parameters structure used by
these functions.
.PP
\&\fIOP_cipher_get_params()\fR gets details of the algorithm implementation
and stores them in \fIparams\fR.
.PP
\&\fIOP_cipher_set_ctx_params()\fR sets cipher operation parameters for the
provider side cipher context \fIcctx\fR to \fIparams\fR.
Any parameter settings are additional to any that were previously set.
.PP
\&\fIOP_cipher_get_ctx_params()\fR gets cipher operation details details from
the given provider side cipher context \fIcctx\fR and stores them in \fIparams\fR.
.PP
\&\fIOP_cipher_gettable_params()\fR, \fIOP_cipher_gettable_ctx_params()\fR, and
\&\fIOP_cipher_settable_ctx_params()\fR all return constant \fB\s-1OSSL_PARAM\s0\fR arrays
as descriptors of the parameters that \fIOP_cipher_get_params()\fR,
\&\fIOP_cipher_get_ctx_params()\fR, and \fIOP_cipher_set_ctx_params()\fR can handle,
respectively.
.PP
Parameters currently recognised by built-in ciphers are as follows. Not all
parameters are relevant to, or are understood by all ciphers:
.ie n .IP """padding"" (\fB\s-1OSSL_CIPHER_PARAM_PADDING\s0\fR) <unsigned integer>" 4
.el .IP "``padding'' (\fB\s-1OSSL_CIPHER_PARAM_PADDING\s0\fR) <unsigned integer>" 4
.IX Item "padding (OSSL_CIPHER_PARAM_PADDING) <unsigned integer>"
Sets the padding mode for the associated cipher ctx.
Setting a value of 1 will turn padding on.
Setting a value of 0 will turn padding off.
.ie n .IP """mode"" (\fB\s-1OSSL_CIPHER_PARAM_MODE\s0\fR) <unsigned integer>" 4
.el .IP "``mode'' (\fB\s-1OSSL_CIPHER_PARAM_MODE\s0\fR) <unsigned integer>" 4
.IX Item "mode (OSSL_CIPHER_PARAM_MODE) <unsigned integer>"
Gets the mode for the associated cipher algorithm.
See \fIEVP_CIPHER_mode\fR\|(3) for a list of valid modes.
.ie n .IP """blocksize"" (\fB\s-1OSSL_CIPHER_PARAM_BLOCK_SIZE\s0\fR) <unsigned integer>" 4
.el .IP "``blocksize'' (\fB\s-1OSSL_CIPHER_PARAM_BLOCK_SIZE\s0\fR) <unsigned integer>" 4
.IX Item "blocksize (OSSL_CIPHER_PARAM_BLOCK_SIZE) <unsigned integer>"
Gets the block size for the associated cipher algorithm.
The block size should be 1 for stream ciphers.
Note that the block size for a cipher may be different to the block size for
the underlying encryption/decryption primitive.
For example \s-1AES\s0 in \s-1CTR\s0 mode has a block size of 1 (because it operates like a
stream cipher), even though \s-1AES\s0 has a block size of 16.
The length of the \*(L"blocksize\*(R" parameter should not exceed that of a \fBsize_t\fR.
.ie n .IP """flags"" (\fB\s-1OSSL_CIPHER_PARAM_FLAGS\s0\fR) <unsigned integer>" 4
.el .IP "``flags'' (\fB\s-1OSSL_CIPHER_PARAM_FLAGS\s0\fR) <unsigned integer>" 4
.IX Item "flags (OSSL_CIPHER_PARAM_FLAGS) <unsigned integer>"
Gets any flags for the associated cipher algorithm.
See \fIEVP_CIPHER_meth_set_flags\fR\|(3) for a list of currently defined cipher
flags.
The length of the \*(L"flags\*(R" parameter should equal that of an
\&\fBunsigned long int\fR.
.ie n .IP """keylen"" (\fB\s-1OSSL_CIPHER_PARAM_KEYLEN\s0\fR) <unsigned integer>" 4
.el .IP "``keylen'' (\fB\s-1OSSL_CIPHER_PARAM_KEYLEN\s0\fR) <unsigned integer>" 4
.IX Item "keylen (OSSL_CIPHER_PARAM_KEYLEN) <unsigned integer>"
Gets the key length for the associated cipher algorithm.
This can also be used to get or set the key length for the associated cipher
ctx.
The length of the \*(L"keylen\*(R" parameter should not exceed that of a \fBsize_t\fR.
.ie n .IP """ivlen"" (\fB\s-1OSSL_CIPHER_PARAM_IVLEN\s0\fR) <unsigned integer>" 4
.el .IP "``ivlen'' (\fB\s-1OSSL_CIPHER_PARAM_IVLEN\s0\fR) <unsigned integer>" 4
.IX Item "ivlen (OSSL_CIPHER_PARAM_IVLEN) <unsigned integer>"
Gets the \s-1IV\s0 length for the associated cipher algorithm.
The length of the \*(L"ivlen\*(R" parameter should not exceed that of a \fBsize_t\fR.
.ie n .IP """iv"" (\fB\s-1OSSL_CIPHER_PARAM_IV\s0\fR) <octet string \s-1OR\s0 octet ptr>" 4
.el .IP "``iv'' (\fB\s-1OSSL_CIPHER_PARAM_IV\s0\fR) <octet string \s-1OR\s0 octet ptr>" 4
.IX Item "iv (OSSL_CIPHER_PARAM_IV) <octet string OR octet ptr>"
Gets the \s-1IV\s0 for the associated cipher ctx.
.ie n .IP """num"" (\fB\s-1OSSL_CIPHER_PARAM_NUM\s0\fR) <unsigned integer>" 4
.el .IP "``num'' (\fB\s-1OSSL_CIPHER_PARAM_NUM\s0\fR) <unsigned integer>" 4
.IX Item "num (OSSL_CIPHER_PARAM_NUM) <unsigned integer>"
Gets or sets the cipher specific \*(L"num\*(R" parameter for the associated cipher ctx.
Built-in ciphers typically use this to track how much of the current underlying
block has been \*(L"used\*(R" already.
.ie n .IP """tag"" (\fB\s-1OSSL_CIPHER_PARAM_AEAD_TAG\s0\fR) <octet string>" 4
.el .IP "``tag'' (\fB\s-1OSSL_CIPHER_PARAM_AEAD_TAG\s0\fR) <octet string>" 4
.IX Item "tag (OSSL_CIPHER_PARAM_AEAD_TAG) <octet string>"
Gets or sets the \s-1AEAD\s0 tag for the associated cipher ctx.
See \*(L"\s-1AEAD\s0 Interface\*(R" in \fIEVP_EncryptInit\fR\|(3).
.ie n .IP """taglen"" (\fB\s-1OSSL_CIPHER_PARAM_AEAD_TAGLEN\s0\fR) <unsigned integer>" 4
.el .IP "``taglen'' (\fB\s-1OSSL_CIPHER_PARAM_AEAD_TAGLEN\s0\fR) <unsigned integer>" 4
.IX Item "taglen (OSSL_CIPHER_PARAM_AEAD_TAGLEN) <unsigned integer>"
Gets the tag length to be used for an \s-1AEAD\s0 cipher for the associated cipher ctx.
It returns a default value if it has not been set.
The length of the \*(L"taglen\*(R" parameter should not exceed that of a \fBsize_t\fR.
.ie n .IP """tlsaad"" (\fB\s-1OSSL_CIPHER_PARAM_AEAD_TLS1_AAD\s0\fR) <octet string>" 4
.el .IP "``tlsaad'' (\fB\s-1OSSL_CIPHER_PARAM_AEAD_TLS1_AAD\s0\fR) <octet string>" 4
.IX Item "tlsaad (OSSL_CIPHER_PARAM_AEAD_TLS1_AAD) <octet string>"
Sets TLSv1.2 \s-1AAD\s0 information for the associated cipher ctx.
TLSv1.2 \s-1AAD\s0 information is always 13 bytes in length and is as defined for the
\&\*(L"additional_data\*(R" field described in section 6.2.3.3 of \s-1RFC5246\s0.
.ie n .IP """tlsaadpad"" (\fB\s-1OSSL_CIPHER_PARAM_AEAD_TLS1_AAD_PAD\s0\fR) <unsigned integer>" 4
.el .IP "``tlsaadpad'' (\fB\s-1OSSL_CIPHER_PARAM_AEAD_TLS1_AAD_PAD\s0\fR) <unsigned integer>" 4
.IX Item "tlsaadpad (OSSL_CIPHER_PARAM_AEAD_TLS1_AAD_PAD) <unsigned integer>"
Gets the length of the tag that will be added to a \s-1TLS\s0 record for the \s-1AEAD\s0
tag for the associated cipher ctx.
The length of the \*(L"tlsaadpad\*(R" parameter should not exceed that of a \fBsize_t\fR.
.ie n .IP """tlsivfixed"" (\fB\s-1OSSL_CIPHER_PARAM_AEAD_TLS1_IV_FIXED\s0\fR) <octet string>" 4
.el .IP "``tlsivfixed'' (\fB\s-1OSSL_CIPHER_PARAM_AEAD_TLS1_IV_FIXED\s0\fR) <octet string>" 4
.IX Item "tlsivfixed (OSSL_CIPHER_PARAM_AEAD_TLS1_IV_FIXED) <octet string>"
Sets the fixed portion of an \s-1IV\s0 for an \s-1AEAD\s0 cipher used in a \s-1TLS\s0 record
encryption/ decryption for the associated cipher ctx.
\&\s-1TLS\s0 record encryption/decryption always occurs \*(L"in place\*(R" so that the input and
output buffers are always the same memory location.
\&\s-1AEAD\s0 IVs in TLSv1.2 consist of an implicit \*(L"fixed\*(R" part and an explicit part
that varies with every record.
Setting a \s-1TLS\s0 fixed \s-1IV\s0 changes a cipher to encrypt/decrypt \s-1TLS\s0 records.
\&\s-1TLS\s0 records are encrypted/decrypted using a single OP_cipher_cipher call per
record.
For a record decryption the first bytes of the input buffer will be the explicit
part of the \s-1IV\s0 and the final bytes of the input buffer will be the \s-1AEAD\s0 tag.
The length of the explicit part of the \s-1IV\s0 and the tag length will depend on the
cipher in use and will be defined in the \s-1RFC\s0 for the relevant ciphersuite.
In order to allow for \*(L"in place\*(R" decryption the plaintext output should be
written to the same location in the output buffer that the ciphertext payload
was read from, i.e. immediately after the explicit \s-1IV\s0.
.Sp
When encrypting a record the first bytes of the input buffer will be empty to
allow space for the explicit \s-1IV\s0, as will the final bytes where the tag will
be written.
The length of the input buffer will include the length of the explicit \s-1IV\s0, the
payload, and the tag bytes.
The cipher implementation should generate the explicit \s-1IV\s0 and write it to the
beginning of the output buffer, do \*(L"in place\*(R" encryption of the payload and
write that to the output buffer, and finally add the tag onto the end of the
output buffer.
.Sp
Whether encrypting or decrypting the value written to \fI*outl\fR in the
OP_cipher_cipher call should be the length of the payload excluding the explicit
\&\s-1IV\s0 length and the tag length.
.ie n .IP """ivlen"" (\fB\s-1OSSL_CIPHER_PARAM_AEAD_IVLEN\s0\fR) <unsigned integer>" 4
.el .IP "``ivlen'' (\fB\s-1OSSL_CIPHER_PARAM_AEAD_IVLEN\s0\fR) <unsigned integer>" 4
.IX Item "ivlen (OSSL_CIPHER_PARAM_AEAD_IVLEN) <unsigned integer>"
Sets the \s-1IV\s0 length to be used for an \s-1AEAD\s0 cipher for the associated cipher ctx.
The length of the \*(L"ivlen\*(R" parameter should not exceed that of a \fBsize_t\fR.
.ie n .IP """mackey"" (\fB\s-1OSSL_CIPHER_PARAM_AEAD_MAC_KEY\s0\fR) <octet string>" 4
.el .IP "``mackey'' (\fB\s-1OSSL_CIPHER_PARAM_AEAD_MAC_KEY\s0\fR) <octet string>" 4
.IX Item "mackey (OSSL_CIPHER_PARAM_AEAD_MAC_KEY) <octet string>"
Sets the \s-1MAC\s0 key used by composite \s-1AEAD\s0 ciphers such as \s-1AES\-CBC\-HMAC\-SHA256\s0.
.ie n .IP """randkey"" (\fB\s-1OSSL_CIPHER_PARAM_RANDOM_KEY\s0\fR) <octet string>" 4
.el .IP "``randkey'' (\fB\s-1OSSL_CIPHER_PARAM_RANDOM_KEY\s0\fR) <octet string>" 4
.IX Item "randkey (OSSL_CIPHER_PARAM_RANDOM_KEY) <octet string>"
Gets a implementation specific randomly generated key for the associated
cipher ctx. This is currently only supported by 3DES (which sets the key to
odd parity).
.ie n .IP """alg_id_param"" (\fB\s-1OSSL_CIPHER_PARAM_ALG_ID\s0\fR) <octet string>" 4
.el .IP "``alg_id_param'' (\fB\s-1OSSL_CIPHER_PARAM_ALG_ID\s0\fR) <octet string>" 4
.IX Item "alg_id_param (OSSL_CIPHER_PARAM_ALG_ID) <octet string>"
Used to pass the \s-1DER\s0 encoded AlgorithmIdentifier parameter to or from
the cipher implementation. Functions like \fIEVP_CIPHER_param_to_asn1\fR\|(3)
and \fIEVP_CIPHER_asn1_to_param\fR\|(3) use this parameter for any implementation
that has the flag \fB\s-1EVP_CIPH_FLAG_CUSTOM_ASN1\s0\fR set.
.ie n .IP """rounds"" (\fB\s-1OSSL_CIPHER_PARAM_ROUNDS\s0\fR) <unsigned integer>" 4
.el .IP "``rounds'' (\fB\s-1OSSL_CIPHER_PARAM_ROUNDS\s0\fR) <unsigned integer>" 4
.IX Item "rounds (OSSL_CIPHER_PARAM_ROUNDS) <unsigned integer>"
Sets or gets the number of rounds to be used for a cipher.
This is used by the \s-1RC5\s0 cipher.
.ie n .IP """keybits"" (\fB\s-1OSSL_CIPHER_PARAM_RC2_KEYBITS\s0\fR) <unsigned integer>" 4
.el .IP "``keybits'' (\fB\s-1OSSL_CIPHER_PARAM_RC2_KEYBITS\s0\fR) <unsigned integer>" 4
.IX Item "keybits (OSSL_CIPHER_PARAM_RC2_KEYBITS) <unsigned integer>"
Gets or sets the effective keybits used for a \s-1RC2\s0 cipher.
The length of the \*(L"keybits\*(R" parameter should not exceed that of a \fBsize_t\fR.
.ie n .IP """speed"" (\fB\s-1OSSL_CIPHER_PARAM_SPEED\s0\fR) <unsigned integer>" 4
.el .IP "``speed'' (\fB\s-1OSSL_CIPHER_PARAM_SPEED\s0\fR) <unsigned integer>" 4
.IX Item "speed (OSSL_CIPHER_PARAM_SPEED) <unsigned integer>"
Sets the speed option for the associated cipher ctx. This is only supported
by \s-1AES\s0 \s-1SIV\s0 ciphers which disallow multiple operations by default.
Setting \*(L"speed\*(R" to 1 allows another encrypt or decrypt operation to be
performed. This is used for performance testing.
.ie n .IP """tlsivgen"" (\fB\s-1OSSL_CIPHER_PARAM_AEAD_TLS1_GET_IV_GEN\s0\fR) <octet string>" 4
.el .IP "``tlsivgen'' (\fB\s-1OSSL_CIPHER_PARAM_AEAD_TLS1_GET_IV_GEN\s0\fR) <octet string>" 4
.IX Item "tlsivgen (OSSL_CIPHER_PARAM_AEAD_TLS1_GET_IV_GEN) <octet string>"
Gets the invocation field generated for encryption.
Can only be called after \*(L"tlsivfixed\*(R" is set.
This is only used for \s-1GCM\s0 mode.
.ie n .IP """tlsivinv"" (\fB\s-1OSSL_CIPHER_PARAM_AEAD_TLS1_SET_IV_INV\s0\fR) <octet string>" 4
.el .IP "``tlsivinv'' (\fB\s-1OSSL_CIPHER_PARAM_AEAD_TLS1_SET_IV_INV\s0\fR) <octet string>" 4
.IX Item "tlsivinv (OSSL_CIPHER_PARAM_AEAD_TLS1_SET_IV_INV) <octet string>"
Sets the invocation field used for decryption.
Can only be called after \*(L"tlsivfixed\*(R" is set.
This is only used for \s-1GCM\s0 mode.
.ie n .IP """tls1multi_enc"" (\fB\s-1OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_ENC\s0\fR) <octet string>" 4
.el .IP "``tls1multi_enc'' (\fB\s-1OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_ENC\s0\fR) <octet string>" 4
.IX Item "tls1multi_enc (OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_ENC) <octet string>"
Triggers a multiblock tls1 encrypt operation for a tls1 aware cipher that supports
sending 4 or 8 records in one go.
The cipher performs both the \s-1MAC\s0 and encrypt stages and constructs the record
headers itself.
\&\*(L"tls1multi_enc\*(R" supplies the output buffer for the encrypt operation,
\&\*(L"tls1multi_encin\*(R" & \*(L"tls1multi_interleave\*(R" must also be set in order to supply
values to the encrypt operation.
.ie n .IP """tls1multi_enclen"" (\fB\s-1OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_ENC_LEN\s0\fR) <unsigned integer>" 4
.el .IP "``tls1multi_enclen'' (\fB\s-1OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_ENC_LEN\s0\fR) <unsigned integer>" 4
.IX Item "tls1multi_enclen (OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_ENC_LEN) <unsigned integer>"
Get the total length of the record returned from the \*(L"tls1multi_enc\*(R" operation.
.ie n .IP """tls1multi_interleave"" (\fB\s-1OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_INTERLEAVE\s0\fR) <unsigned integer>" 4
.el .IP "``tls1multi_interleave'' (\fB\s-1OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_INTERLEAVE\s0\fR) <unsigned integer>" 4
.IX Item "tls1multi_interleave (OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_INTERLEAVE) <unsigned integer>"
Sets or gets the number of records being sent in one go for a tls1 multiblock
cipher operation (either 4 or 8 records).
.ie n .IP """tls1multi_encin"" (\fB\s-1OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_ENC_IN\s0\fR) <octet string>" 4
.el .IP "``tls1multi_encin'' (\fB\s-1OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_ENC_IN\s0\fR) <octet string>" 4
.IX Item "tls1multi_encin (OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_ENC_IN) <octet string>"
Supplies the data to encrypt for a tls1 multiblock cipher operation.
.ie n .IP """tls1multi_maxsndfrag"" (\fB\s-1OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_MAX_SEND_FRAGMENT\s0\fR) <unsigned integer>" 4
.el .IP "``tls1multi_maxsndfrag'' (\fB\s-1OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_MAX_SEND_FRAGMENT\s0\fR) <unsigned integer>" 4
.IX Item "tls1multi_maxsndfrag (OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_MAX_SEND_FRAGMENT) <unsigned integer>"
Sets the maximum send fragment size for a tls1 multiblock cipher operation.
It must be set before using \*(L"tls1multi_maxbufsz\*(R".
The length of the \*(L"tls1multi_maxsndfrag\*(R" parameter should not exceed that of a \fBsize_t\fR.
.ie n .IP """tls1multi_maxbufsz"" (\fB\s-1OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_MAX_BUFSIZE\s0\fR) <unsigned integer>" 4
.el .IP "``tls1multi_maxbufsz'' (\fB\s-1OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_MAX_BUFSIZE\s0\fR) <unsigned integer>" 4
.IX Item "tls1multi_maxbufsz (OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_MAX_BUFSIZE) <unsigned integer>"
Gets the maximum record length for a tls1 multiblock cipher operation.
The length of the \*(L"tls1multi_maxbufsz\*(R" parameter should not exceed that of a \fBsize_t\fR.
.ie n .IP """tls1multi_aad"" (\fB\s-1OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_AAD\s0\fR) <octet string>" 4
.el .IP "``tls1multi_aad'' (\fB\s-1OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_AAD\s0\fR) <octet string>" 4
.IX Item "tls1multi_aad (OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_AAD) <octet string>"
Sets the authenticated additional data used by a tls1 multiblock cipher operation.
The supplied data consists of 13 bytes of record data containing:
Bytes 0\-7: The sequence number of the first record
Byte 8: The record type
Byte 9\-10: The protocol version
Byte 11\-12: Input length (Always 0)
.Sp
\&\*(L"tls1multi_interleave\*(R" must also be set for this operation.
.ie n .IP """tls1multi_aadpacklen"" (\fB\s-1OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_AAD_PACKLEN\s0\fR) <unsigned integer>" 4
.el .IP "``tls1multi_aadpacklen'' (\fB\s-1OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_AAD_PACKLEN\s0\fR) <unsigned integer>" 4
.IX Item "tls1multi_aadpacklen (OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_AAD_PACKLEN) <unsigned integer>"
Gets the result of running the \*(L"tls1multi_aad\*(R" operation.
.SH "RETURN VALUES"
.IX Header "RETURN VALUES"
\&\fIOP_cipher_newctx()\fR and \fIOP_cipher_dupctx()\fR should return the newly created
provider side cipher context, or \s-1NULL\s0 on failure.
.PP
\&\fIOP_cipher_encrypt_init()\fR, \fIOP_cipher_decrypt_init()\fR, \fIOP_cipher_update()\fR,
\&\fIOP_cipher_final()\fR, \fIOP_cipher_cipher()\fR, \fIOP_cipher_get_params()\fR,
\&\fIOP_cipher_get_ctx_params()\fR and \fIOP_cipher_set_ctx_params()\fR should return 1 for
success or 0 on error.
.PP
\&\fIOP_cipher_gettable_params()\fR, \fIOP_cipher_gettable_ctx_params()\fR and
\&\fIOP_cipher_settable_ctx_params()\fR should return a constant \fB\s-1OSSL_PARAM\s0\fR
array, or \s-1NULL\s0 if none is offered.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
\&\fIprovider\fR\|(7)
.SH "HISTORY"
.IX Header "HISTORY"
The provider \s-1CIPHER\s0 interface was introduced in OpenSSL 3.0.
.SH "COPYRIGHT"
.IX Header "COPYRIGHT"
Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
.PP
Licensed under the Apache License 2.0 (the \*(L"License\*(R"). You may not use
this file except in compliance with the License. You can obtain a copy
in the file \s-1LICENSE\s0 in the source distribution or at
<https://www.openssl.org/source/license.html>.