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Currently, the DRBG implementation schedules asynchronous works from random_ready_callbacks for reseeding the DRBG instances with output from get_random_bytes() once the latter has sufficient entropy available. However, as the get_random_bytes() initialization state can get queried by means of rng_is_initialized() now, there is no real need for this asynchronous reseeding logic anymore and it's better to keep things simple by doing it synchronously when needed instead, i.e. from drbg_generate() once rng_is_initialized() has flipped to true. Of course, for this to work, drbg_generate() would need some means by which it can tell whether or not rng_is_initialized() has flipped to true since the last seeding from get_random_bytes(). Or equivalently, whether or not the last seed from get_random_bytes() has happened when rng_is_initialized() was still evaluating to false. As it currently stands, enum drbg_seed_state allows for the representation of two different DRBG seeding states: DRBG_SEED_STATE_UNSEEDED and DRBG_SEED_STATE_FULL. The former makes drbg_generate() to invoke a full reseeding operation involving both, the rather expensive jitterentropy as well as the get_random_bytes() randomness sources. The DRBG_SEED_STATE_FULL state on the other hand implies that no reseeding at all is required for a !->pr DRBG variant. Introduce the new DRBG_SEED_STATE_PARTIAL state to enum drbg_seed_state for representing the condition that a DRBG was being seeded when rng_is_initialized() had still been false. In particular, this new state implies that - the given DRBG instance has been fully seeded from the jitterentropy source (if enabled) - and drbg_generate() is supposed to reseed from get_random_bytes() *only* once rng_is_initialized() turns to true. Up to now, the __drbg_seed() helper used to set the given DRBG instance's ->seeded state to constant DRBG_SEED_STATE_FULL. Introduce a new argument allowing for the specification of the to be written ->seeded value instead. Make the first of its two callers, drbg_seed(), determine the appropriate value based on rng_is_initialized(). The remaining caller, drbg_async_seed(), is known to get invoked only once rng_is_initialized() is true, hence let it pass constant DRBG_SEED_STATE_FULL for the new argument to __drbg_seed(). There is no change in behaviour, except for that the pr_devel() in drbg_generate() would now report "unseeded" for ->pr DRBG instances which had last been seeded when rng_is_initialized() was still evaluating to false. Signed-off-by: Nicolai Stange <nstange@suse.de> Reviewed-by: Stephan Müller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> |
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| .. | ||
| internal | ||
| acompress.h | ||
| aead.h | ||
| aes.h | ||
| akcipher.h | ||
| algapi.h | ||
| arc4.h | ||
| asym_tpm_subtype.h | ||
| authenc.h | ||
| b128ops.h | ||
| blake2b.h | ||
| blake2s.h | ||
| blowfish.h | ||
| cast_common.h | ||
| cast5.h | ||
| cast6.h | ||
| chacha.h | ||
| chacha20poly1305.h | ||
| cryptd.h | ||
| ctr.h | ||
| curve25519.h | ||
| des.h | ||
| dh.h | ||
| drbg.h | ||
| ecc_curve.h | ||
| ecdh.h | ||
| engine.h | ||
| gcm.h | ||
| gf128mul.h | ||
| ghash.h | ||
| hash_info.h | ||
| hash.h | ||
| hmac.h | ||
| if_alg.h | ||
| kpp.h | ||
| md5.h | ||
| nhpoly1305.h | ||
| null.h | ||
| padlock.h | ||
| pcrypt.h | ||
| pkcs7.h | ||
| poly1305.h | ||
| public_key.h | ||
| rng.h | ||
| scatterwalk.h | ||
| serpent.h | ||
| sha1_base.h | ||
| sha1.h | ||
| sha2.h | ||
| sha3.h | ||
| sha256_base.h | ||
| sha512_base.h | ||
| skcipher.h | ||
| sm2.h | ||
| sm3_base.h | ||
| sm3.h | ||
| sm4.h | ||
| streebog.h | ||
| twofish.h | ||
| xts.h | ||