#ifndef HEADER_RAND_LCL_H
# define HEADER_RAND_LCL_H
-# define ENTROPY_NEEDED 32 /* require 256 bits = 32 bytes of randomness */
+# include <openssl/aes.h>
+# include <openssl/evp.h>
+# include <openssl/sha.h>
+# include <openssl/hmac.h>
+# include <openssl/ec.h>
+# include "internal/rand.h"
-# if !defined(USE_MD5_RAND) && !defined(USE_SHA1_RAND) && !defined(USE_MDC2_RAND) && !defined(USE_MD2_RAND)
-# define USE_SHA1_RAND
-# endif
+/*
+ * Amount of randomness (in bytes) we want for initial seeding.
+ * This is based on the fact that we use AES-128 as the CRBG, and
+ * that we use the derivation function. If either of those changes,
+ * (see rand_init() in rand_lib.c), change this.
+ */
+# define RANDOMNESS_NEEDED 16
-# include <openssl/evp.h>
-# define MD_Update(a,b,c) EVP_DigestUpdate(a,b,c)
-# define MD_Final(a,b) EVP_DigestFinal_ex(a,b,NULL)
-# if defined(USE_MD5_RAND)
-# include <openssl/md5.h>
-# define MD_DIGEST_LENGTH MD5_DIGEST_LENGTH
-# define MD_Init(a) EVP_DigestInit_ex(a,EVP_md5(), NULL)
-# define MD(a,b,c) EVP_Digest(a,b,c,NULL,EVP_md5(), NULL)
-# elif defined(USE_SHA1_RAND)
-# include <openssl/sha.h>
-# define MD_DIGEST_LENGTH SHA_DIGEST_LENGTH
-# define MD_Init(a) EVP_DigestInit_ex(a,EVP_sha1(), NULL)
-# define MD(a,b,c) EVP_Digest(a,b,c,NULL,EVP_sha1(), NULL)
-# elif defined(USE_MDC2_RAND)
-# include <openssl/mdc2.h>
-# define MD_DIGEST_LENGTH MDC2_DIGEST_LENGTH
-# define MD_Init(a) EVP_DigestInit_ex(a,EVP_mdc2(), NULL)
-# define MD(a,b,c) EVP_Digest(a,b,c,NULL,EVP_mdc2(), NULL)
-# elif defined(USE_MD2_RAND)
-# include <openssl/md2.h>
-# define MD_DIGEST_LENGTH MD2_DIGEST_LENGTH
-# define MD_Init(a) EVP_DigestInit_ex(a,EVP_md2(), NULL)
-# define MD(a,b,c) EVP_Digest(a,b,c,NULL,EVP_md2(), NULL)
-# endif
-
-void rand_hw_xor(unsigned char *buf, size_t num);
+/* How many times to read the TSC as a randomness source. */
+# define TSC_READ_COUNT 4
+
+/* Maximum amount of randomness to hold in RAND_BYTES_BUFFER. */
+# define MAX_RANDOMNESS_HELD (4 * RANDOMNESS_NEEDED)
+
+/* Maximum count allowed in reseeding */
+# define MAX_RESEED (1 << 24)
+
+/* How often we call RAND_poll() in drbg_entropy_from_system */
+# define RAND_POLL_RETRIES 8
+
+/* Max size of entropy, addin, etc. Larger than any reasonable value */
+# define DRBG_MAX_LENGTH 0x7ffffff0
+
+
+/* DRBG status values */
+typedef enum drbg_status_e {
+ DRBG_UNINITIALISED,
+ DRBG_READY,
+ DRBG_RESEED,
+ DRBG_ERROR
+} DRBG_STATUS;
+
+
+/*
+ * A buffer of random bytes to be fed as "entropy" into the DRBG. RAND_add()
+ * adds data to the buffer, and the drbg_entropy_from_system() pulls data from
+ * the buffer. We have a separate data structure because of the way the
+ * API is defined; otherwise we'd run into deadlocks (RAND_bytes ->
+ * RAND_DRBG_generate* -> drbg_entropy_from_system -> RAND_poll -> RAND_add ->
+ * drbg_add*; the functions with an asterisk lock).
+ */
+typedef struct rand_bytes_buffer_st {
+ CRYPTO_RWLOCK *lock;
+ unsigned char *buff;
+ size_t size;
+ size_t curr;
+ int secure;
+} RAND_BYTES_BUFFER;
+
+/*
+ * The state of a DRBG AES-CTR.
+ */
+typedef struct rand_drbg_ctr_st {
+ AES_KEY ks;
+ size_t keylen;
+ unsigned char K[32];
+ unsigned char V[16];
+ /* Temp variables used by derivation function */
+ AES_KEY df_ks;
+ AES_KEY df_kxks;
+ /* Temporary block storage used by ctr_df */
+ unsigned char bltmp[16];
+ size_t bltmp_pos;
+ unsigned char KX[48];
+} RAND_DRBG_CTR;
+
+
+/*
+ * The state of all types of DRBGs, even though we only have CTR mode
+ * right now.
+ */
+struct rand_drbg_st {
+ CRYPTO_RWLOCK *lock;
+ RAND_DRBG *parent;
+ int nid; /* the underlying algorithm */
+ int fork_count;
+ unsigned short flags; /* various external flags */
+ char filled;
+ char secure;
+ /*
+ * This is a fixed-size buffer, but we malloc to make it a little
+ * harder to find; a classic security/performance trade-off.
+ */
+ int size;
+ unsigned char *randomness;
+
+ /* These parameters are setup by the per-type "init" function. */
+ int strength;
+ size_t max_request;
+ size_t min_entropy, max_entropy;
+ size_t min_nonce, max_nonce;
+ size_t max_pers, max_adin;
+ unsigned int reseed_counter;
+ unsigned int reseed_interval;
+ size_t seedlen;
+ DRBG_STATUS state;
+
+ /* Application data, mainly used in the KATs. */
+ CRYPTO_EX_DATA ex_data;
+
+ /* Implementation specific structures; was a union, but inline for now */
+ RAND_DRBG_CTR ctr;
+
+ /* 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;
+extern RAND_BYTES_BUFFER rand_bytes;
+extern RAND_DRBG rand_drbg;
+extern RAND_DRBG priv_drbg;
+
+/* How often we've forked (only incremented in child). */
+extern int rand_fork_count;
+
+/* Hardware-based seeding functions. */
+void rand_read_tsc(RAND_poll_fn cb, void *arg);
+int rand_read_cpu(RAND_poll_fn cb, void *arg);
+
+/* DRBG entropy callbacks. */
+void drbg_release_entropy(RAND_DRBG *drbg, unsigned char *out);
+size_t drbg_entropy_from_parent(RAND_DRBG *drbg,
+ unsigned char **pout,
+ int entropy, size_t min_len, size_t max_len);
+size_t drbg_entropy_from_system(RAND_DRBG *drbg,
+ unsigned char **pout,
+ int entropy, size_t min_len, size_t max_len);
+
+/* DRBG functions implementing AES-CTR */
+int ctr_init(RAND_DRBG *drbg);
+int ctr_uninstantiate(RAND_DRBG *drbg);
+int ctr_instantiate(RAND_DRBG *drbg,
+ const unsigned char *ent, size_t entlen,
+ const unsigned char *nonce, size_t noncelen,
+ const unsigned char *pers, size_t perslen);
+int ctr_reseed(RAND_DRBG *drbg,
+ const unsigned char *ent, size_t entlen,
+ const unsigned char *adin, size_t adinlen);
+int ctr_generate(RAND_DRBG *drbg,
+ unsigned char *out, size_t outlen,
+ const unsigned char *adin, size_t adinlen);
#endif
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