diff options
Diffstat (limited to 'include/crypto/rng.h')
| -rw-r--r-- | include/crypto/rng.h | 100 |
1 files changed, 73 insertions, 27 deletions
diff --git a/include/crypto/rng.h b/include/crypto/rng.h index 6e28ea5be9f1..b95ede354a66 100644 --- a/include/crypto/rng.h +++ b/include/crypto/rng.h @@ -2,6 +2,7 @@ * RNG: Random Number Generator algorithms under the crypto API * * Copyright (c) 2008 Neil Horman <nhorman@tuxdriver.com> + * Copyright (c) 2015 Herbert Xu <herbert@gondor.apana.org.au> * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the Free @@ -15,6 +16,50 @@ #include <linux/crypto.h> +struct crypto_rng; + +/** + * struct rng_alg - random number generator definition + * + * @generate: The function defined by this variable obtains a + * random number. The random number generator transform + * must generate the random number out of the context + * provided with this call, plus any additional data + * if provided to the call. + * @seed: Seed or reseed the random number generator. With the + * invocation of this function call, the random number + * generator shall become ready for generation. If the + * random number generator requires a seed for setting + * up a new state, the seed must be provided by the + * consumer while invoking this function. The required + * size of the seed is defined with @seedsize . + * @set_ent: Set entropy that would otherwise be obtained from + * entropy source. Internal use only. + * @seedsize: The seed size required for a random number generator + * initialization defined with this variable. Some + * random number generators does not require a seed + * as the seeding is implemented internally without + * the need of support by the consumer. In this case, + * the seed size is set to zero. + * @base: Common crypto API algorithm data structure. + */ +struct rng_alg { + int (*generate)(struct crypto_rng *tfm, + const u8 *src, unsigned int slen, + u8 *dst, unsigned int dlen); + int (*seed)(struct crypto_rng *tfm, const u8 *seed, unsigned int slen); + void (*set_ent)(struct crypto_rng *tfm, const u8 *data, + unsigned int len); + + unsigned int seedsize; + + struct crypto_alg base; +}; + +struct crypto_rng { + struct crypto_tfm base; +}; + extern struct crypto_rng *crypto_default_rng; int crypto_get_default_rng(void); @@ -27,11 +72,6 @@ void crypto_put_default_rng(void); * 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 @@ -52,15 +92,7 @@ static inline struct crypto_rng *__crypto_rng_cast(struct crypto_tfm *tfm) * 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) -{ - type &= ~CRYPTO_ALG_TYPE_MASK; - type |= CRYPTO_ALG_TYPE_RNG; - mask |= CRYPTO_ALG_TYPE_MASK; - - return __crypto_rng_cast(crypto_alloc_base(alg_name, type, mask)); -} +struct crypto_rng *crypto_alloc_rng(const char *alg_name, u32 type, u32 mask); static inline struct crypto_tfm *crypto_rng_tfm(struct crypto_rng *tfm) { @@ -77,12 +109,8 @@ static inline struct crypto_tfm *crypto_rng_tfm(struct crypto_rng *tfm) */ static inline struct rng_alg *crypto_rng_alg(struct crypto_rng *tfm) { - return &crypto_rng_tfm(tfm)->__crt_alg->cra_rng; -} - -static inline struct rng_tfm *crypto_rng_crt(struct crypto_rng *tfm) -{ - return &crypto_rng_tfm(tfm)->crt_rng; + return container_of(crypto_rng_tfm(tfm)->__crt_alg, + struct rng_alg, base); } /** @@ -91,7 +119,28 @@ static inline struct rng_tfm *crypto_rng_crt(struct crypto_rng *tfm) */ static inline void crypto_free_rng(struct crypto_rng *tfm) { - crypto_free_tfm(crypto_rng_tfm(tfm)); + crypto_destroy_tfm(tfm, crypto_rng_tfm(tfm)); +} + +/** + * crypto_rng_generate() - get random number + * @tfm: cipher handle + * @src: Input buffer holding additional data, may be NULL + * @slen: Length of additional data + * @dst: 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; < 0 if an error occurred + */ +static inline int crypto_rng_generate(struct crypto_rng *tfm, + const u8 *src, unsigned int slen, + u8 *dst, unsigned int dlen) +{ + return crypto_rng_alg(tfm)->generate(tfm, src, slen, dst, dlen); } /** @@ -108,7 +157,7 @@ static inline void crypto_free_rng(struct crypto_rng *tfm) 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); + return crypto_rng_generate(tfm, NULL, 0, rdata, dlen); } /** @@ -128,11 +177,8 @@ static inline int crypto_rng_get_bytes(struct crypto_rng *tfm, * * 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); -} +int crypto_rng_reset(struct crypto_rng *tfm, const u8 *seed, + unsigned int slen); /** * crypto_rng_seedsize() - obtain seed size of RNG |