Documentation/crypto/devel-algos.rst

5 --------------------------------------------
14 filled with each, struct crypto_alg, must be considered -- see below
47 Single-Block Symmetric Ciphers [CIPHER]
48 ---------------------------------------
55 block at a time and there are no dependencies between blocks at all.
69 Struct cipher_alg defines a single block cipher.
74 during any of these are in-flight.
78              KEY ---.    PLAINTEXT ---.
80               .cia_setkey() -> .cia_encrypt()
82                                       '-----> CIPHERTEXT
91       KEY1 --.    PLAINTEXT1 --.         KEY2 --.    PLAINTEXT2 --.
93        .cia_setkey() -> .cia_encrypt() -> .cia_setkey() -> .cia_encrypt()
95                                '---> CIPHERTEXT1                  '---> CIPHERTEXT2
98 Multi-Block Ciphers
99 -------------------
103 This section describes the multi-block cipher transformation
104 implementations. The multi-block ciphers are used for transformations
111 The registration of multi-block cipher algorithms is one of the most
124 Struct skcipher_alg defines a multi-block cipher, or more generally, a
125 length-preserving symmetric cipher algorithm.
137 --------------
174 during any of these are in-flight. Please note that calling .init()
180        I)   DATA -----------.
182              .init() -> .update() -> .final()      ! .update() might not be called
184                          '----'         '---> HASH
186        II)  DATA -----------.-----------.
188              .init() -> .update() -> .finup()      ! .update() may not be called
190                          '----'         '---> HASH
192        III) DATA -----------.
196                             '---------------> HASH
204        KEY--.                 DATA--.
206         .setkey() -> .init() -> .update() -> .export()   at all in this scenario.
208                                  '-----'         '--> PARTIAL_HASH
210        ----------- other transformations happen here -----------
212        PARTIAL_HASH--.   DATA1--.
214                  .import -> .update() -> .final()     ! .update() may not be called
216                              '----'         '--> HASH1
218        PARTIAL_HASH--.   DATA2-.
220                  .import -> .finup()
222                                '---------------> HASH2
225 - call .init() and then (as many times) .update()
226 - _not_ call any of .final(), .finup() or .export() at any point in future
228 In other words implementations should mind the resource allocation and clean-up.