openssl/crypto/rand/rand_local.h
Dr. Matthias St. Pierre ae4186b004 Fix header file include guard names
Make the include guards consistent by renaming them systematically according
to the naming conventions below

For the public header files (in the 'include/openssl' directory), the guard
names try to match the path specified in the include directives, with
all letters converted to upper case and '/' and '.' replaced by '_'. For the
private header files files, an extra 'OSSL_' is added as prefix.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9333)
2019-09-28 20:26:36 +02:00

361 lines
13 KiB
C

/*
* Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#ifndef OSSL_CRYPTO_RAND_LOCAL_H
# define OSSL_CRYPTO_RAND_LOCAL_H
# include <openssl/aes.h>
# include <openssl/evp.h>
# include <openssl/sha.h>
# include <openssl/hmac.h>
# include <openssl/ec.h>
# include <openssl/rand_drbg.h>
# include "internal/tsan_assist.h"
# include "crypto/rand.h"
# include "internal/numbers.h"
/* How many times to read the TSC as a randomness source. */
# define TSC_READ_COUNT 4
/* Maximum reseed intervals */
# define MAX_RESEED_INTERVAL (1 << 24)
# define MAX_RESEED_TIME_INTERVAL (1 << 20) /* approx. 12 days */
/* Default reseed intervals */
# define MASTER_RESEED_INTERVAL (1 << 8)
# define SLAVE_RESEED_INTERVAL (1 << 16)
# define MASTER_RESEED_TIME_INTERVAL (60*60) /* 1 hour */
# define SLAVE_RESEED_TIME_INTERVAL (7*60) /* 7 minutes */
/*
* The number of bytes that constitutes an atomic lump of entropy with respect
* to the FIPS 140-2 section 4.9.2 Conditional Tests. The size is somewhat
* arbitrary, the smaller the value, the less entropy is consumed on first
* read but the higher the probability of the test failing by accident.
*
* The value is in bytes.
*/
#define CRNGT_BUFSIZ 16
/*
* Maximum input size for the DRBG (entropy, nonce, personalization string)
*
* NIST SP800 90Ar1 allows a maximum of (1 << 35) bits i.e., (1 << 32) bytes.
*
* We lower it to 'only' INT32_MAX bytes, which is equivalent to 2 gigabytes.
*/
# define DRBG_MAX_LENGTH INT32_MAX
/* The default nonce */
#ifdef CHARSET_EBCDIC
# define DRBG_DEFAULT_PERS_STRING { 0x4f, 0x70, 0x65, 0x6e, 0x53, 0x53, \
0x4c, 0x20, 0x4e, 0x49, 0x53, 0x54, 0x20, 0x53, 0x50, 0x20, 0x38, 0x30, \
0x30, 0x2d, 0x39, 0x30, 0x41, 0x20, 0x44, 0x52, 0x42, 0x47, 0x00};
#else
# define DRBG_DEFAULT_PERS_STRING "OpenSSL NIST SP 800-90A DRBG"
#endif
/*
* Maximum allocation size for RANDOM_POOL buffers
*
* The max_len value for the buffer provided to the rand_drbg_get_entropy()
* callback is currently 2^31 bytes (2 gigabytes), if a derivation function
* is used. Since this is much too large to be allocated, the rand_pool_new()
* function chooses more modest values as default pool length, bounded
* by RAND_POOL_MIN_LENGTH and RAND_POOL_MAX_LENGTH
*
* The choice of the RAND_POOL_FACTOR is large enough such that the
* RAND_POOL can store a random input which has a lousy entropy rate of
* 8/256 (= 0.03125) bits per byte. This input will be sent through the
* derivation function which 'compresses' the low quality input into a
* high quality output.
*
* The factor 1.5 below is the pessimistic estimate for the extra amount
* of entropy required when no get_nonce() callback is defined.
*/
# define RAND_POOL_FACTOR 256
# define RAND_POOL_MAX_LENGTH (RAND_POOL_FACTOR * \
3 * (RAND_DRBG_STRENGTH / 16))
/*
* = (RAND_POOL_FACTOR * \
* 1.5 * (RAND_DRBG_STRENGTH / 8))
*/
/*
* Initial allocation minimum.
*
* There is a distinction between the secure and normal allocation minimums.
* Ideally, the secure allocation size should be a power of two. The normal
* allocation size doesn't have any such restriction.
*
* The secure value is based on 128 bits of secure material, which is 16 bytes.
* Typically, the DRBGs will set a minimum larger than this so optimal
* allocation ought to take place (for full quality seed material).
*
* The normal value has been chosed by noticing that the rand_drbg_get_nonce
* function is usually the largest of the built in allocation (twenty four
* bytes and then appending another sixteen bytes). This means the buffer ends
* with 40 bytes. The value of forty eight is comfortably above this which
* allows some slack in the platform specific values used.
*/
# define RAND_POOL_MIN_ALLOCATION(secure) ((secure) ? 16 : 48)
/* DRBG status values */
typedef enum drbg_status_e {
DRBG_UNINITIALISED,
DRBG_READY,
DRBG_ERROR
} DRBG_STATUS;
/* instantiate */
typedef int (*RAND_DRBG_instantiate_fn)(RAND_DRBG *ctx,
const unsigned char *ent,
size_t entlen,
const unsigned char *nonce,
size_t noncelen,
const unsigned char *pers,
size_t perslen);
/* reseed */
typedef int (*RAND_DRBG_reseed_fn)(RAND_DRBG *ctx,
const unsigned char *ent,
size_t entlen,
const unsigned char *adin,
size_t adinlen);
/* generate output */
typedef int (*RAND_DRBG_generate_fn)(RAND_DRBG *ctx,
unsigned char *out,
size_t outlen,
const unsigned char *adin,
size_t adinlen);
/* uninstantiate */
typedef int (*RAND_DRBG_uninstantiate_fn)(RAND_DRBG *ctx);
/*
* The DRBG methods
*/
typedef struct rand_drbg_method_st {
RAND_DRBG_instantiate_fn instantiate;
RAND_DRBG_reseed_fn reseed;
RAND_DRBG_generate_fn generate;
RAND_DRBG_uninstantiate_fn uninstantiate;
} RAND_DRBG_METHOD;
/* 888 bits from SP800-90Ar1 10.1 table 2 */
#define HASH_PRNG_MAX_SEEDLEN (888/8)
typedef struct rand_drbg_hash_st {
EVP_MD *md;
EVP_MD_CTX *ctx;
size_t blocklen;
unsigned char V[HASH_PRNG_MAX_SEEDLEN];
unsigned char C[HASH_PRNG_MAX_SEEDLEN];
/* Temporary value storage: should always exceed max digest length */
unsigned char vtmp[HASH_PRNG_MAX_SEEDLEN];
} RAND_DRBG_HASH;
typedef struct rand_drbg_hmac_st {
EVP_MD *md;
HMAC_CTX *ctx;
size_t blocklen;
unsigned char K[EVP_MAX_MD_SIZE];
unsigned char V[EVP_MAX_MD_SIZE];
} RAND_DRBG_HMAC;
/*
* The state of a DRBG AES-CTR.
*/
typedef struct rand_drbg_ctr_st {
EVP_CIPHER_CTX *ctx;
EVP_CIPHER_CTX *ctx_df;
EVP_CIPHER *cipher;
size_t keylen;
unsigned char K[32];
unsigned char V[16];
/* Temporary block storage used by ctr_df */
unsigned char bltmp[16];
size_t bltmp_pos;
unsigned char KX[48];
} RAND_DRBG_CTR;
/*
* The 'random pool' acts as a dumb container for collecting random
* input from various entropy sources. The pool has no knowledge about
* whether its randomness is fed into a legacy RAND_METHOD via RAND_add()
* or into a new style RAND_DRBG. It is the callers duty to 1) initialize the
* random pool, 2) pass it to the polling callbacks, 3) seed the RNG, and
* 4) cleanup the random pool again.
*
* The random pool contains no locking mechanism because its scope and
* lifetime is intended to be restricted to a single stack frame.
*/
struct rand_pool_st {
unsigned char *buffer; /* points to the beginning of the random pool */
size_t len; /* current number of random bytes contained in the pool */
int attached; /* true pool was attached to existing buffer */
int secure; /* 1: allocated on the secure heap, 0: otherwise */
size_t min_len; /* minimum number of random bytes requested */
size_t max_len; /* maximum number of random bytes (allocated buffer size) */
size_t alloc_len; /* current number of bytes allocated */
size_t entropy; /* current entropy count in bits */
size_t entropy_requested; /* requested entropy count in bits */
};
/*
* The state of all types of DRBGs, even though we only have CTR mode
* right now.
*/
struct rand_drbg_st {
CRYPTO_RWLOCK *lock;
/* The library context this DRBG is associated with, if any */
OPENSSL_CTX *libctx;
RAND_DRBG *parent;
int secure; /* 1: allocated on the secure heap, 0: otherwise */
int type; /* the nid of the underlying algorithm */
/*
* Stores the return value of openssl_get_fork_id() as of when we last
* reseeded. The DRBG reseeds automatically whenever drbg->fork_id !=
* openssl_get_fork_id(). Used to provide fork-safety and reseed this
* DRBG in the child process.
*/
int fork_id;
unsigned short flags; /* various external flags */
/*
* The random_data is used by RAND_add()/drbg_add() to attach random
* data to the global drbg, such that the rand_drbg_get_entropy() callback
* can pull it during instantiation and reseeding. This is necessary to
* reconcile the different philosophies of the RAND and the RAND_DRBG
* with respect to how randomness is added to the RNG during reseeding
* (see PR #4328).
*/
struct rand_pool_st *seed_pool;
/*
* Auxiliary pool for additional data.
*/
struct rand_pool_st *adin_pool;
/*
* The following parameters are setup by the per-type "init" function.
*
* The supported types and their init functions are:
* (1) CTR_DRBG: drbg_ctr_init().
* (2) HMAC_DRBG: drbg_hmac_init().
* (3) HASH_DRBG: drbg_hash_init().
*
* The parameters are closely related to the ones described in
* section '10.2.1 CTR_DRBG' of [NIST SP 800-90Ar1], with one
* crucial difference: In the NIST standard, all counts are given
* in bits, whereas in OpenSSL entropy counts are given in bits
* and buffer lengths are given in bytes.
*
* Since this difference has lead to some confusion in the past,
* (see [GitHub Issue #2443], formerly [rt.openssl.org #4055])
* the 'len' suffix has been added to all buffer sizes for
* clarification.
*/
int strength;
size_t max_request;
size_t min_entropylen, max_entropylen;
size_t min_noncelen, max_noncelen;
size_t max_perslen, max_adinlen;
/*
* Counts the number of generate requests since the last reseed
* (Starts at 1). This value is the reseed_counter as defined in
* NIST SP 800-90Ar1
*/
unsigned int reseed_gen_counter;
/*
* Maximum number of generate requests until a reseed is required.
* This value is ignored if it is zero.
*/
unsigned int reseed_interval;
/* Stores the time when the last reseeding occurred */
time_t reseed_time;
/*
* Specifies the maximum time interval (in seconds) between reseeds.
* This value is ignored if it is zero.
*/
time_t reseed_time_interval;
/*
* Counts the number of reseeds since instantiation.
* This value is ignored if it is zero.
*
* This counter is used only for seed propagation from the <master> DRBG
* to its two children, the <public> and <private> DRBG. This feature is
* very special and its sole purpose is to ensure that any randomness which
* is added by RAND_add() or RAND_seed() will have an immediate effect on
* the output of RAND_bytes() resp. RAND_priv_bytes().
*/
TSAN_QUALIFIER unsigned int reseed_prop_counter;
unsigned int reseed_next_counter;
size_t seedlen;
DRBG_STATUS state;
/* Application data, mainly used in the KATs. */
CRYPTO_EX_DATA ex_data;
/* Implementation specific data */
union {
RAND_DRBG_CTR ctr;
RAND_DRBG_HASH hash;
RAND_DRBG_HMAC hmac;
} data;
/* Implementation specific methods */
RAND_DRBG_METHOD *meth;
/* Callback functions. See comments in rand_lib.c */
RAND_DRBG_get_entropy_fn get_entropy;
RAND_DRBG_cleanup_entropy_fn cleanup_entropy;
RAND_DRBG_get_nonce_fn get_nonce;
RAND_DRBG_cleanup_nonce_fn cleanup_nonce;
};
/* The global RAND method, and the global buffer and DRBG instance. */
extern RAND_METHOD rand_meth;
/* DRBG helpers */
int rand_drbg_restart(RAND_DRBG *drbg,
const unsigned char *buffer, size_t len, size_t entropy);
size_t rand_drbg_seedlen(RAND_DRBG *drbg);
/* locking api */
int rand_drbg_lock(RAND_DRBG *drbg);
int rand_drbg_unlock(RAND_DRBG *drbg);
int rand_drbg_enable_locking(RAND_DRBG *drbg);
/* initializes the DRBG implementation */
int drbg_ctr_init(RAND_DRBG *drbg);
int drbg_hash_init(RAND_DRBG *drbg);
int drbg_hmac_init(RAND_DRBG *drbg);
/*
* Entropy call back for the FIPS 140-2 section 4.9.2 Conditional Tests.
* These need to be exposed for the unit tests.
*/
int rand_crngt_get_entropy_cb(OPENSSL_CTX *ctx, RAND_POOL *pool,
unsigned char *buf, unsigned char *md,
unsigned int *md_size);
extern int (*crngt_get_entropy)(OPENSSL_CTX *ctx, RAND_POOL *pool,
unsigned char *buf, unsigned char *md,
unsigned int *md_size);
#endif