AcoSail/kernel_optimize_test
8
0
Fork 0
forked from luck/tmp_suning_uos_patched
Code Pull Requests Activity

crypto: doc - RNG API documentation

Browse Source 
The API function calls exported by the kernel crypto API for RNGs to
be used by consumers are documented.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Stephan Mueller 2014-11-12 05:25:31 +01:00 committed by Herbert Xu
parent e63b673f60
commit aa1b6fbcbe
1 changed files with 80 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

80
include/crypto/rng.h
View File

@ -20,11 +20,38 @@ extern struct crypto_rng *crypto_default_rng;
int crypto_get_default_rng(void);
void crypto_put_default_rng(void);
/**
* DOC: Random number generator API
*
* The random number generator API is used with the ciphers of type
* CRYPTO_ALG_TYPE_RNG (listed as type "rng" in /proc/crypto)
*/
static inline struct crypto_rng *__crypto_rng_cast(struct crypto_tfm *tfm)
{
return (struct crypto_rng *)tfm;
}
/**
* crypto_alloc_rng() -- allocate RNG handle
* @alg_name: is the cra_name / name or cra_driver_name / driver name of the
* message digest cipher
* @type: specifies the type of the cipher
* @mask: specifies the mask for the cipher
*
* Allocate a cipher handle for a random number generator. The returned struct
* crypto_rng is the cipher handle that is required for any subsequent
* API invocation for that random number generator.
*
* For all random number generators, this call creates a new private copy of
* the random number generator that does not share a state with other
* instances. The only exception is the "krng" random number generator which
* is a kernel crypto API use case for the get_random_bytes() function of the
* /dev/random driver.
*
* Return: allocated cipher handle in case of success; IS_ERR() is true in case
* of an error, PTR_ERR() returns the error code.
*/
static inline struct crypto_rng *crypto_alloc_rng(const char *alg_name,
u32 type, u32 mask)
{
@ -40,6 +67,14 @@ static inline struct crypto_tfm *crypto_rng_tfm(struct crypto_rng *tfm)
return &tfm->base;
}
/**
* crypto_rng_alg - obtain name of RNG
* @tfm: cipher handle
*
* Return the generic name (cra_name) of the initialized random number generator
*
* Return: generic name string
*/
static inline struct rng_alg *crypto_rng_alg(struct crypto_rng *tfm)
{
return &crypto_rng_tfm(tfm)->__crt_alg->cra_rng;
@ -50,23 +85,68 @@ static inline struct rng_tfm *crypto_rng_crt(struct crypto_rng *tfm)
return &crypto_rng_tfm(tfm)->crt_rng;
}
/**
* crypto_free_rng() - zeroize and free RNG handle
* @tfm: cipher handle to be freed
*/
static inline void crypto_free_rng(struct crypto_rng *tfm)
{
crypto_free_tfm(crypto_rng_tfm(tfm));
}
/**
* crypto_rng_get_bytes() - get random number
* @tfm: cipher handle
* @rdata: output buffer holding the random numbers
* @dlen: length of the output buffer
*
* This function fills the caller-allocated buffer with random numbers using the
* random number generator referenced by the cipher handle.
*
* Return: > 0 function was successful and returns the number of generated
* bytes; < 0 if an error occurred
*/
static inline int crypto_rng_get_bytes(struct crypto_rng *tfm,
u8 *rdata, unsigned int dlen)
{
return crypto_rng_crt(tfm)->rng_gen_random(tfm, rdata, dlen);
}
/**
* crypto_rng_reset() - re-initialize the RNG
* @tfm: cipher handle
* @seed: seed input data
* @slen: length of the seed input data
*
* The reset function completely re-initializes the random number generator
* referenced by the cipher handle by clearing the current state. The new state
* is initialized with the caller provided seed or automatically, depending
* on the random number generator type (the ANSI X9.31 RNG requires
* caller-provided seed, the SP800-90A DRBGs perform an automatic seeding).
* The seed is provided as a parameter to this function call. The provided seed
* should have the length of the seed size defined for the random number
* generator as defined by crypto_rng_seedsize.
*
* Return: 0 if the setting of the key was successful; < 0 if an error occurred
*/
static inline int crypto_rng_reset(struct crypto_rng *tfm,
u8 *seed, unsigned int slen)
{
return crypto_rng_crt(tfm)->rng_reset(tfm, seed, slen);
}
/**
* crypto_rng_seedsize() - obtain seed size of RNG
* @tfm: cipher handle
*
* The function returns the seed size for the random number generator
* referenced by the cipher handle. This value may be zero if the random
* number generator does not implement or require a reseeding. For example,
* the SP800-90A DRBGs implement an automated reseeding after reaching a
* pre-defined threshold.
*
* Return: seed size for the random number generator
*/
static inline int crypto_rng_seedsize(struct crypto_rng *tfm)
{
return crypto_rng_alg(tfm)->seedsize;