€•ch      Œsphinx.addnodes”Œdocument”“”)”}”(Œ	rawsource”Œ ”Œchildren”]”(Œtranslations”ŒLanguagesNode”“”)”}”(hhh]”(h Œpending_xref”“”)”}”(hhh]”Œdocutils.nodes”ŒText”“”ŒChinese (Simplified)”…””}”Œparent”hsbaŒ
attributes”}”(Œids”]”Œclasses”]”Œnames”]”Œdupnames”]”Œbackrefs”]”Œ	refdomain”Œstd”Œreftype”Œdoc”Œ	reftarget”Œ&/translations/zh_CN/crypto/devel-algos”Œmodname”NŒ	classname”NŒrefexplicit”ˆuŒtagname”hhhubh)”}”(hhh]”hŒChinese (Traditional)”…””}”hh2sbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ&/translations/zh_TW/crypto/devel-algos”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒItalian”…””}”hhFsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ&/translations/it_IT/crypto/devel-algos”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒJapanese”…””}”hhZsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ&/translations/ja_JP/crypto/devel-algos”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒKorean”…””}”hhnsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ&/translations/ko_KR/crypto/devel-algos”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒSpanish”…””}”hh‚sbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ&/translations/sp_SP/crypto/devel-algos”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubeh}”(h]”h ]”h"]”h$]”h&]”Œcurrent_language”ŒEnglish”uh1h
hhŒ	_document”hŒsource”NŒline”NubhŒsection”“”)”}”(hhh]”(hŒtitle”“”)”}”(hŒDeveloping Cipher Algorithms”h]”hŒDeveloping Cipher Algorithms”…””}”(hh¨hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hh£hžhhŸŒ@/var/lib/git/docbuild/linux/Documentation/crypto/devel-algos.rst”h Kubh¢)”}”(hhh]”(h§)”}”(hŒ,Registering And Unregistering Transformation”h]”hŒ,Registering And Unregistering Transformation”…””}”(hhºhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hh·hžhhŸh¶h KubhŒ	paragraph”“”)”}”(hX7  There are three distinct types of registration functions in the Crypto
API. One is used to register a generic cryptographic transformation,
while the other two are specific to HASH transformations and
COMPRESSion. We will discuss the latter two in a separate chapter, here
we will only look at the generic ones.”h]”hX7  There are three distinct types of registration functions in the Crypto
API. One is used to register a generic cryptographic transformation,
while the other two are specific to HASH transformations and
COMPRESSion. We will discuss the latter two in a separate chapter, here
we will only look at the generic ones.”…””}”(hhÊhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h Khh·hžhubhÉ)”}”(hŒ±Before discussing the register functions, the data structure to be
filled with each, struct crypto_alg, must be considered -- see below
for a description of this data structure.”h]”hŒ±Before discussing the register functions, the data structure to be
filled with each, struct crypto_alg, must be considered -- see below
for a description of this data structure.”…””}”(hhØhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h Khh·hžhubhÉ)”}”(hXi  The generic registration functions can be found in
include/linux/crypto.h and their definition can be seen below. The
former function registers a single transformation, while the latter
works on an array of transformation descriptions. The latter is useful
when registering transformations in bulk, for example when a driver
implements multiple transformations.”h]”hXi  The generic registration functions can be found in
include/linux/crypto.h and their definition can be seen below. The
former function registers a single transformation, while the latter
works on an array of transformation descriptions. The latter is useful
when registering transformations in bulk, for example when a driver
implements multiple transformations.”…””}”(hhæhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h Khh·hžhubhŒliteral_block”“”)”}”(hŒnint crypto_register_alg(struct crypto_alg *alg);
int crypto_register_algs(struct crypto_alg *algs, int count);”h]”hŒnint crypto_register_alg(struct crypto_alg *alg);
int crypto_register_algs(struct crypto_alg *algs, int count);”…””}”hhösbah}”(h]”h ]”h"]”h$]”h&]”Œ	xml:space”Œpreserve”uh1hôhŸh¶h Khh·hžhubhÉ)”}”(hŒ5The counterparts to those functions are listed below.”h]”hŒ5The counterparts to those functions are listed below.”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h Khh·hžhubhõ)”}”(hŒtvoid crypto_unregister_alg(struct crypto_alg *alg);
void crypto_unregister_algs(struct crypto_alg *algs, int count);”h]”hŒtvoid crypto_unregister_alg(struct crypto_alg *alg);
void crypto_unregister_algs(struct crypto_alg *algs, int count);”…””}”hj  sbah}”(h]”h ]”h"]”h$]”h&]”j  j  uh1hôhŸh¶h K"hh·hžhubhÉ)”}”(hŒòThe registration functions return 0 on success, or a negative errno
value on failure.  crypto_register_algs() succeeds only if it
successfully registered all the given algorithms; if it fails partway
through, then any changes are rolled back.”h]”hŒòThe registration functions return 0 on success, or a negative errno
value on failure.  crypto_register_algs() succeeds only if it
successfully registered all the given algorithms; if it fails partway
through, then any changes are rolled back.”…””}”(hj"  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h K&hh·hžhubhÉ)”}”(hŒ•The unregistration functions always succeed, so they don't have a
return value.  Don't try to unregister algorithms that aren't
currently registered.”h]”hŒ›The unregistration functions always succeed, so they donâ€™t have a
return value.  Donâ€™t try to unregister algorithms that arenâ€™t
currently registered.”…””}”(hj0  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h K+hh·hžhubeh}”(h]”Œ,registering-and-unregistering-transformation”ah ]”h"]”Œ,registering and unregistering transformation”ah$]”h&]”uh1h¡hh£hžhhŸh¶h Kubh¢)”}”(hhh]”(h§)”}”(hŒ'Single-Block Symmetric Ciphers [CIPHER]”h]”hŒ'Single-Block Symmetric Ciphers [CIPHER]”…””}”(hjI  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hjF  hžhhŸh¶h K0ubhÉ)”}”(hŒ-Example of transformations: aes, serpent, ...”h]”hŒ-Example of transformations: aes, serpent, ...”…””}”(hjW  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h K2hjF  hžhubhÉ)”}”(hX  This section describes the simplest of all transformation
implementations, that being the CIPHER type used for symmetric ciphers.
The CIPHER type is used for transformations which operate on exactly one
block at a time and there are no dependencies between blocks at all.”h]”hX  This section describes the simplest of all transformation
implementations, that being the CIPHER type used for symmetric ciphers.
The CIPHER type is used for transformations which operate on exactly one
block at a time and there are no dependencies between blocks at all.”…””}”(hje  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h K4hjF  hžhubh¢)”}”(hhh]”(h§)”}”(hŒRegistration specifics”h]”hŒRegistration specifics”…””}”(hjv  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hjs  hžhhŸh¶h K:ubhÉ)”}”(hŒÄThe registration of [CIPHER] algorithm is specific in that struct
crypto_alg field .cra_type is empty. The .cra_u.cipher has to be
filled in with proper callbacks to implement this transformation.”h]”hŒÄThe registration of [CIPHER] algorithm is specific in that struct
crypto_alg field .cra_type is empty. The .cra_u.cipher has to be
filled in with proper callbacks to implement this transformation.”…””}”(hj„  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h K<hjs  hžhubhÉ)”}”(hŒSee struct cipher_alg below.”h]”hŒSee struct cipher_alg below.”…””}”(hj’  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h K@hjs  hžhubeh}”(h]”Œregistration-specifics”ah ]”h"]”h$]”Œregistration specifics”ah&]”uh1h¡hjF  hžhhŸh¶h K:Œ
referenced”Kubh¢)”}”(hhh]”(h§)”}”(hŒ(Cipher Definition With struct cipher_alg”h]”hŒ(Cipher Definition With struct cipher_alg”…””}”(hj¬  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hj©  hžhhŸh¶h KCubhÉ)”}”(hŒ0Struct cipher_alg defines a single block cipher.”h]”hŒ0Struct cipher_alg defines a single block cipher.”…””}”(hjº  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h KEhj©  hžhubhÉ)”}”(hŒ÷Here are schematics of how these functions are called when operated from
other part of the kernel. Note that the .cia_setkey() call might happen
before or after any of these schematics happen, but must not happen
during any of these are in-flight.”h]”hŒ÷Here are schematics of how these functions are called when operated from
other part of the kernel. Note that the .cia_setkey() call might happen
before or after any of these schematics happen, but must not happen
during any of these are in-flight.”…””}”(hjÈ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h KGhj©  hžhubhõ)”}”(hŒKEY ---.    PLAINTEXT ---.
       v                 v
 .cia_setkey() -> .cia_encrypt()
                         |
                         '-----> CIPHERTEXT”h]”hŒKEY ---.    PLAINTEXT ---.
       v                 v
 .cia_setkey() -> .cia_encrypt()
                         |
                         '-----> CIPHERTEXT”…””}”hjÖ  sbah}”(h]”h ]”h"]”h$]”h&]”j  j  uh1hôhŸh¶h KNhj©  hžhubhÉ)”}”(hŒVPlease note that a pattern where .cia_setkey() is called multiple times
is also valid:”h]”hŒVPlease note that a pattern where .cia_setkey() is called multiple times
is also valid:”…””}”(hjä  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h KUhj©  hžhubhõ)”}”(hXK  KEY1 --.    PLAINTEXT1 --.         KEY2 --.    PLAINTEXT2 --.
       v                 v                v                 v
 .cia_setkey() -> .cia_encrypt() -> .cia_setkey() -> .cia_encrypt()
                         |                                  |
                         '---> CIPHERTEXT1                  '---> CIPHERTEXT2”h]”hXK  KEY1 --.    PLAINTEXT1 --.         KEY2 --.    PLAINTEXT2 --.
       v                 v                v                 v
 .cia_setkey() -> .cia_encrypt() -> .cia_setkey() -> .cia_encrypt()
                         |                                  |
                         '---> CIPHERTEXT1                  '---> CIPHERTEXT2”…””}”hjò  sbah}”(h]”h ]”h"]”h$]”h&]”j  j  uh1hôhŸh¶h K[hj©  hžhubeh}”(h]”Œ(cipher-definition-with-struct-cipher-alg”ah ]”h"]”Œ(cipher definition with struct cipher_alg”ah$]”h&]”uh1h¡hjF  hžhhŸh¶h KCubeh}”(h]”Œ%single-block-symmetric-ciphers-cipher”ah ]”h"]”Œ'single-block symmetric ciphers [cipher]”ah$]”h&]”uh1h¡hh£hžhhŸh¶h K0ubh¢)”}”(hhh]”(h§)”}”(hŒMulti-Block Ciphers”h]”hŒMulti-Block Ciphers”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hj  hžhhŸh¶h KcubhÉ)”}”(hŒ3Example of transformations: cbc(aes), chacha20, ...”h]”hŒ3Example of transformations: cbc(aes), chacha20, ...”…””}”(hj!  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h Kehj  hžhubhÉ)”}”(hX  This section describes the multi-block cipher transformation
implementations. The multi-block ciphers are used for transformations
which operate on scatterlists of data supplied to the transformation
functions. They output the result into a scatterlist of data as well.”h]”hX  This section describes the multi-block cipher transformation
implementations. The multi-block ciphers are used for transformations
which operate on scatterlists of data supplied to the transformation
functions. They output the result into a scatterlist of data as well.”…””}”(hj/  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h Kghj  hžhubh¢)”}”(hhh]”(h§)”}”(hŒRegistration Specifics”h]”hŒRegistration Specifics”…””}”(hj@  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hj=  hžhhŸh¶h KmubhÉ)”}”(hŒsThe registration of multi-block cipher algorithms is one of the most
standard procedures throughout the crypto API.”h]”hŒsThe registration of multi-block cipher algorithms is one of the most
standard procedures throughout the crypto API.”…””}”(hjN  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h Kohj=  hžhubhÉ)”}”(hX„  Note, if a cipher implementation requires a proper alignment of data,
the caller should use the functions of crypto_skcipher_alignmask() to
identify a memory alignment mask. The kernel crypto API is able to
process requests that are unaligned. This implies, however, additional
overhead as the kernel crypto API needs to perform the realignment of
the data which may imply moving of data.”h]”hX„  Note, if a cipher implementation requires a proper alignment of data,
the caller should use the functions of crypto_skcipher_alignmask() to
identify a memory alignment mask. The kernel crypto API is able to
process requests that are unaligned. This implies, however, additional
overhead as the kernel crypto API needs to perform the realignment of
the data which may imply moving of data.”…””}”(hj\  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h Krhj=  hžhubeh}”(h]”Œid1”ah ]”h"]”h$]”j¦  ah&]”uh1h¡hj  hžhhŸh¶h Kmj¨  Kubh¢)”}”(hhh]”(h§)”}”(hŒ*Cipher Definition With struct skcipher_alg”h]”hŒ*Cipher Definition With struct skcipher_alg”…””}”(hjt  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hjq  hžhhŸh¶h KzubhÉ)”}”(hŒtStruct skcipher_alg defines a multi-block cipher, or more generally, a
length-preserving symmetric cipher algorithm.”h]”hŒtStruct skcipher_alg defines a multi-block cipher, or more generally, a
length-preserving symmetric cipher algorithm.”…””}”(hj‚  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h K|hjq  hžhubeh}”(h]”Œ*cipher-definition-with-struct-skcipher-alg”ah ]”h"]”Œ*cipher definition with struct skcipher_alg”ah$]”h&]”uh1h¡hj  hžhhŸh¶h Kzubh¢)”}”(hhh]”(h§)”}”(hŒScatterlist handling”h]”hŒScatterlist handling”…””}”(hj›  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hj˜  hžhhŸh¶h K€ubhÉ)”}”(hX'  Some drivers will want to use the Generic ScatterWalk in case the
hardware needs to be fed separate chunks of the scatterlist which
contains the plaintext and will contain the ciphertext. Please refer
to the ScatterWalk interface offered by the Linux kernel scatter /
gather list implementation.”h]”hX'  Some drivers will want to use the Generic ScatterWalk in case the
hardware needs to be fed separate chunks of the scatterlist which
contains the plaintext and will contain the ciphertext. Please refer
to the ScatterWalk interface offered by the Linux kernel scatter /
gather list implementation.”…””}”(hj©  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h K‚hj˜  hžhubeh}”(h]”Œscatterlist-handling”ah ]”h"]”Œscatterlist handling”ah$]”h&]”uh1h¡hj  hžhhŸh¶h K€ubeh}”(h]”Œmulti-block-ciphers”ah ]”h"]”Œmulti-block ciphers”ah$]”h&]”uh1h¡hh£hžhhŸh¶h Kcubh¢)”}”(hhh]”(h§)”}”(hŒHashing [HASH]”h]”hŒHashing [HASH]”…””}”(hjÊ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hjÇ  hžhhŸh¶h K‰ubhÉ)”}”(hŒ8Example of transformations: crc32, md5, sha1, sha256,...”h]”hŒ8Example of transformations: crc32, md5, sha1, sha256,...”…””}”(hjØ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h K‹hjÇ  hžhubh¢)”}”(hhh]”(h§)”}”(hŒ0Registering And Unregistering The Transformation”h]”hŒ0Registering And Unregistering The Transformation”…””}”(hjé  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hjæ  hžhhŸh¶h KŽubhÉ)”}”(hX  There are multiple ways to register a HASH transformation, depending on
whether the transformation is synchronous [SHASH] or asynchronous
[AHASH] and the amount of HASH transformations we are registering. You
can find the prototypes defined in include/crypto/internal/hash.h:”h]”hX  There are multiple ways to register a HASH transformation, depending on
whether the transformation is synchronous [SHASH] or asynchronous
[AHASH] and the amount of HASH transformations we are registering. You
can find the prototypes defined in include/crypto/internal/hash.h:”…””}”(hj÷  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h Khjæ  hžhubhõ)”}”(hŒ¤int crypto_register_ahash(struct ahash_alg *alg);

int crypto_register_shash(struct shash_alg *alg);
int crypto_register_shashes(struct shash_alg *algs, int count);”h]”hŒ¤int crypto_register_ahash(struct ahash_alg *alg);

int crypto_register_shash(struct shash_alg *alg);
int crypto_register_shashes(struct shash_alg *algs, int count);”…””}”hj  sbah}”(h]”h ]”h"]”h$]”h&]”j  j  uh1hôhŸh¶h K—hjæ  hžhubhÉ)”}”(hŒUThe respective counterparts for unregistering the HASH transformation
are as follows:”h]”hŒUThe respective counterparts for unregistering the HASH transformation
are as follows:”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h Khjæ  hžhubhõ)”}”(hŒ­void crypto_unregister_ahash(struct ahash_alg *alg);

void crypto_unregister_shash(struct shash_alg *alg);
void crypto_unregister_shashes(struct shash_alg *algs, int count);”h]”hŒ­void crypto_unregister_ahash(struct ahash_alg *alg);

void crypto_unregister_shash(struct shash_alg *alg);
void crypto_unregister_shashes(struct shash_alg *algs, int count);”…””}”hj!  sbah}”(h]”h ]”h"]”h$]”h&]”j  j  uh1hôhŸh¶h K¢hjæ  hžhubeh}”(h]”Œ0registering-and-unregistering-the-transformation”ah ]”h"]”Œ0registering and unregistering the transformation”ah$]”h&]”uh1h¡hjÇ  hžhhŸh¶h KŽubh¢)”}”(hhh]”(h§)”}”(hŒ5Cipher Definition With struct shash_alg and ahash_alg”h]”hŒ5Cipher Definition With struct shash_alg and ahash_alg”…””}”(hj:  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hj7  hžhhŸh¶h K©ubhÉ)”}”(hX_  Here are schematics of how these functions are called when operated from
other part of the kernel. Note that the .setkey() call might happen
before or after any of these schematics happen, but must not happen
during any of these are in-flight. Please note that calling .init()
followed immediately by .final() is also a perfectly valid
transformation.”h]”hX_  Here are schematics of how these functions are called when operated from
other part of the kernel. Note that the .setkey() call might happen
before or after any of these schematics happen, but must not happen
during any of these are in-flight. Please note that calling .init()
followed immediately by .final() is also a perfectly valid
transformation.”…””}”(hjH  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h K«hj7  hžhubhõ)”}”(hXÜ  I)   DATA -----------.
                     v
      .init() -> .update() -> .final()      ! .update() might not be called
                  ^    |         |            at all in this scenario.
                  '----'         '---> HASH

II)  DATA -----------.-----------.
                     v           v
      .init() -> .update() -> .finup()      ! .update() may not be called
                  ^    |         |            at all in this scenario.
                  '----'         '---> HASH

III) DATA -----------.
                     v
                 .digest()                  ! The entire process is handled
                     |                        by the .digest() call.
                     '---------------> HASH”h]”hXÜ  I)   DATA -----------.
                     v
      .init() -> .update() -> .final()      ! .update() might not be called
                  ^    |         |            at all in this scenario.
                  '----'         '---> HASH

II)  DATA -----------.-----------.
                     v           v
      .init() -> .update() -> .finup()      ! .update() may not be called
                  ^    |         |            at all in this scenario.
                  '----'         '---> HASH

III) DATA -----------.
                     v
                 .digest()                  ! The entire process is handled
                     |                        by the .digest() call.
                     '---------------> HASH”…””}”hjV  sbah}”(h]”h ]”h"]”h$]”h&]”j  j  uh1hôhŸh¶h K´hj7  hžhubhÉ)”}”(hŒrHere is a schematic of how the .export()/.import() functions are called
when used from another part of the kernel.”h]”hŒrHere is a schematic of how the .export()/.import() functions are called
when used from another part of the kernel.”…””}”(hjd  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h KÇhj7  hžhubhõ)”}”(hXõ  KEY--.                 DATA--.
     v                       v                  ! .update() may not be called
 .setkey() -> .init() -> .update() -> .export()   at all in this scenario.
                          ^     |         |
                          '-----'         '--> PARTIAL_HASH

----------- other transformations happen here -----------

PARTIAL_HASH--.   DATA1--.
              v          v
          .import -> .update() -> .final()     ! .update() may not be called
                      ^    |         |           at all in this scenario.
                      '----'         '--> HASH1

PARTIAL_HASH--.   DATA2-.
              v         v
          .import -> .finup()
                        |
                        '---------------> HASH2”h]”hXõ  KEY--.                 DATA--.
     v                       v                  ! .update() may not be called
 .setkey() -> .init() -> .update() -> .export()   at all in this scenario.
                          ^     |         |
                          '-----'         '--> PARTIAL_HASH

----------- other transformations happen here -----------

PARTIAL_HASH--.   DATA1--.
              v          v
          .import -> .update() -> .final()     ! .update() may not be called
                      ^    |         |           at all in this scenario.
                      '----'         '--> HASH1

PARTIAL_HASH--.   DATA2-.
              v         v
          .import -> .finup()
                        |
                        '---------------> HASH2”…””}”hjr  sbah}”(h]”h ]”h"]”h$]”h&]”j  j  uh1hôhŸh¶h KÌhj7  hžhubhÉ)”}”(hŒ»Note that it is perfectly legal to "abandon" a request object:
- call .init() and then (as many times) .update()
- _not_ call any of .final(), .finup() or .export() at any point in future”h]”hŒ¿Note that it is perfectly legal to â€œabandonâ€ a request object:
- call .init() and then (as many times) .update()
- _not_ call any of .final(), .finup() or .export() at any point in future”…””}”(hj€  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h Kàhj7  hžhubhÉ)”}”(hŒãIn other words implementations should mind the resource allocation and clean-up.
No resources related to request objects should remain allocated after a call
to .init() or .update(), since there might be no chance to free them.”h]”hŒãIn other words implementations should mind the resource allocation and clean-up.
No resources related to request objects should remain allocated after a call
to .init() or .update(), since there might be no chance to free them.”…””}”(hjŽ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h Kähj7  hžhubeh}”(h]”Œ5cipher-definition-with-struct-shash-alg-and-ahash-alg”ah ]”h"]”Œ5cipher definition with struct shash_alg and ahash_alg”ah$]”h&]”uh1h¡hjÇ  hžhhŸh¶h K©ubh¢)”}”(hhh]”(h§)”}”(hŒ-Specifics Of Asynchronous HASH Transformation”h]”hŒ-Specifics Of Asynchronous HASH Transformation”…””}”(hj§  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hj¤  hžhhŸh¶h KêubhÉ)”}”(hŒ©Some of the drivers will want to use the Generic ScatterWalk in case the
implementation needs to be fed separate chunks of the scatterlist which
contains the input data.”h]”hŒ©Some of the drivers will want to use the Generic ScatterWalk in case the
implementation needs to be fed separate chunks of the scatterlist which
contains the input data.”…””}”(hjµ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhŸh¶h Kìhj¤  hžhubeh}”(h]”Œ-specifics-of-asynchronous-hash-transformation”ah ]”h"]”Œ-specifics of asynchronous hash transformation”ah$]”h&]”uh1h¡hjÇ  hžhhŸh¶h Kêubeh}”(h]”Œhashing-hash”ah ]”h"]”Œhashing [hash]”ah$]”h&]”uh1h¡hh£hžhhŸh¶h K‰ubeh}”(h]”Œdeveloping-cipher-algorithms”ah ]”h"]”Œdeveloping cipher algorithms”ah$]”h&]”uh1h¡hhhžhhŸh¶h Kubeh}”(h]”h ]”h"]”h$]”h&]”Œsource”h¶uh1hŒcurrent_source”NŒcurrent_line”NŒsettings”Œdocutils.frontend”ŒValues”“”)”}”(h¦NŒ	generator”NŒ	datestamp”NŒsource_link”NŒ
source_url”NŒtoc_backlinks”Œentry”Œfootnote_backlinks”KŒsectnum_xform”KŒstrip_comments”NŒstrip_elements_with_classes”NŒstrip_classes”NŒreport_level”KŒ
halt_level”KŒexit_status_level”KŒdebug”NŒwarning_stream”NŒ	traceback”ˆŒinput_encoding”Œ	utf-8-sig”Œinput_encoding_error_handler”Œstrict”Œoutput_encoding”Œutf-8”Œoutput_encoding_error_handler”jþ  Œerror_encoding”Œutf-8”Œerror_encoding_error_handler”Œbackslashreplace”Œlanguage_code”Œen”Œrecord_dependencies”NŒconfig”NŒ	id_prefix”hŒauto_id_prefix”Œid”Œdump_settings”NŒdump_internals”NŒdump_transforms”NŒdump_pseudo_xml”NŒexpose_internals”NŒstrict_visitor”NŒ_disable_config”NŒ_source”h¶Œ_destination”NŒ_config_files”]”Œ7/var/lib/git/docbuild/linux/Documentation/docutils.conf”aŒfile_insertion_enabled”ˆŒraw_enabled”KŒline_length_limit”M'Œpep_references”NŒpep_base_url”Œhttps://peps.python.org/”Œpep_file_url_template”Œpep-%04d”Œrfc_references”NŒrfc_base_url”Œ&https://datatracker.ietf.org/doc/html/”Œ	tab_width”KŒtrim_footnote_reference_space”‰Œsyntax_highlight”Œlong”Œsmart_quotes”ˆŒsmartquotes_locales”]”Œcharacter_level_inline_markup”‰Œdoctitle_xform”‰Œdocinfo_xform”KŒsectsubtitle_xform”‰Œimage_loading”Œlink”Œembed_stylesheet”‰Œcloak_email_addresses”ˆŒsection_self_link”‰Œenv”NubŒreporter”NŒindirect_targets”]”Œsubstitution_defs”}”Œsubstitution_names”}”Œrefnames”}”Œrefids”}”Œnameids”}”(jØ  jÕ  jC  j@  j  j
  Œregistration specifics”Nj  j  jÄ  jÁ  j•  j’  j¼  j¹  jÐ  jÍ  j4  j1  j¡  jž  jÈ  jÅ  uŒ	nametypes”}”(jØ  ‰jC  ‰j  ‰jB  ‰j  ‰jÄ  ‰j•  ‰j¼  ‰jÐ  ‰j4  ‰j¡  ‰jÈ  ‰uh}”(jÕ  h£j@  h·j
  jF  j¢  js  j  j©  jÁ  j  jl  j=  j’  jq  j¹  j˜  jÍ  jÇ  j1  jæ  jž  j7  jÅ  j¤  uŒfootnote_refs”}”Œcitation_refs”}”Œautofootnotes”]”Œautofootnote_refs”]”Œsymbol_footnotes”]”Œsymbol_footnote_refs”]”Œ	footnotes”]”Œ	citations”]”Œautofootnote_start”KŒsymbol_footnote_start”K Œ
id_counter”Œcollections”ŒCounter”“”}”j  Ks…”R”Œparse_messages”]”hŒsystem_message”“”)”}”(hhh]”hÉ)”}”(hŒ9Duplicate implicit target name: "registration specifics".”h]”hŒ=Duplicate implicit target name: â€œregistration specificsâ€.”…””}”(hjf  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÈhjc  ubah}”(h]”h ]”h"]”h$]”h&]”jl  aŒlevel”KŒtype”ŒINFO”Œsource”h¶Œline”Kmuh1ja  hj=  hžhhŸh¶h KmubaŒtransform_messages”]”Œtransformer”NŒinclude_log”]”Œ
decoration”Nhžhub.