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Diffstat (limited to 'Documentation/crypto/devel-algos.rst')
| -rw-r--r-- | Documentation/crypto/devel-algos.rst | 44 |
1 files changed, 16 insertions, 28 deletions
diff --git a/Documentation/crypto/devel-algos.rst b/Documentation/crypto/devel-algos.rst index f9d288015acc..9b7782f4f6e0 100644 --- a/Documentation/crypto/devel-algos.rst +++ b/Documentation/crypto/devel-algos.rst @@ -31,33 +31,23 @@ The counterparts to those functions are listed below. :: - int crypto_unregister_alg(struct crypto_alg *alg); - int crypto_unregister_algs(struct crypto_alg *algs, int count); + void crypto_unregister_alg(struct crypto_alg *alg); + void crypto_unregister_algs(struct crypto_alg *algs, int count); -Notice that both registration and unregistration functions do return a -value, so make sure to handle errors. A return code of zero implies -success. Any return code < 0 implies an error. +The 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. -The bulk registration/unregistration functions register/unregister each -transformation in the given array of length count. They handle errors as -follows: - -- crypto_register_algs() succeeds if and only if it successfully - registers all the given transformations. If an error occurs partway - through, then it rolls back successful registrations before returning - the error code. Note that if a driver needs to handle registration - errors for individual transformations, then it will need to use the - non-bulk function crypto_register_alg() instead. - -- crypto_unregister_algs() tries to unregister all the given - transformations, continuing on error. It logs errors and always - returns zero. +The unregistration functions always succeed, so they don't have a +return value. Don't try to unregister algorithms that aren't +currently registered. Single-Block Symmetric Ciphers [CIPHER] --------------------------------------- -Example of transformations: aes, arc4, ... +Example of transformations: aes, serpent, ... This section describes the simplest of all transformation implementations, that being the CIPHER type used for symmetric ciphers. @@ -108,7 +98,7 @@ is also valid: Multi-Block Ciphers ------------------- -Example of transformations: cbc(aes), ecb(arc4), ... +Example of transformations: cbc(aes), chacha20, ... This section describes the multi-block cipher transformation implementations. The multi-block ciphers are used for transformations @@ -169,10 +159,10 @@ are as follows: :: - int crypto_unregister_ahash(struct ahash_alg *alg); + void crypto_unregister_ahash(struct ahash_alg *alg); - int crypto_unregister_shash(struct shash_alg *alg); - int crypto_unregister_shashes(struct shash_alg *algs, int count); + void crypto_unregister_shash(struct shash_alg *alg); + void crypto_unregister_shashes(struct shash_alg *algs, int count); Cipher Definition With struct shash_alg and ahash_alg @@ -182,7 +172,7 @@ 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 .finish() is also a perfectly valid +followed immediately by .final() is also a perfectly valid transformation. :: @@ -245,6 +235,4 @@ Specifics Of Asynchronous HASH Transformation 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. The buffer containing the resulting hash will -always be properly aligned to .cra_alignmask so there is no need to -worry about this. +contains the input data. |