diff options
Diffstat (limited to 'roms/edk2/CryptoPkg/Library/OpensslLib/openssl/crypto/rand/rand_lib.c')
| -rw-r--r-- | roms/edk2/CryptoPkg/Library/OpensslLib/openssl/crypto/rand/rand_lib.c | 963 |
1 files changed, 963 insertions, 0 deletions
diff --git a/roms/edk2/CryptoPkg/Library/OpensslLib/openssl/crypto/rand/rand_lib.c b/roms/edk2/CryptoPkg/Library/OpensslLib/openssl/crypto/rand/rand_lib.c new file mode 100644 index 000000000..ab4e9b548 --- /dev/null +++ b/roms/edk2/CryptoPkg/Library/OpensslLib/openssl/crypto/rand/rand_lib.c @@ -0,0 +1,963 @@ +/* + * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved. + * + * Licensed under the OpenSSL license (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 + */ + +#include <stdio.h> +#include <time.h> +#include "internal/cryptlib.h" +#include <openssl/opensslconf.h> +#include "crypto/rand.h" +#include <openssl/engine.h> +#include "internal/thread_once.h" +#include "rand_local.h" +#include "e_os.h" + +#ifndef OPENSSL_NO_ENGINE +/* non-NULL if default_RAND_meth is ENGINE-provided */ +static ENGINE *funct_ref; +static CRYPTO_RWLOCK *rand_engine_lock; +#endif +static CRYPTO_RWLOCK *rand_meth_lock; +static const RAND_METHOD *default_RAND_meth; +static CRYPTO_ONCE rand_init = CRYPTO_ONCE_STATIC_INIT; + +static CRYPTO_RWLOCK *rand_nonce_lock; +static int rand_nonce_count; + +static int rand_inited = 0; + +#ifdef OPENSSL_RAND_SEED_RDTSC +/* + * IMPORTANT NOTE: It is not currently possible to use this code + * because we are not sure about the amount of randomness it provides. + * Some SP900 tests have been run, but there is internal skepticism. + * So for now this code is not used. + */ +# error "RDTSC enabled? Should not be possible!" + +/* + * Acquire entropy from high-speed clock + * + * Since we get some randomness from the low-order bits of the + * high-speed clock, it can help. + * + * Returns the total entropy count, if it exceeds the requested + * entropy count. Otherwise, returns an entropy count of 0. + */ +size_t rand_acquire_entropy_from_tsc(RAND_POOL *pool) +{ + unsigned char c; + int i; + + if ((OPENSSL_ia32cap_P[0] & (1 << 4)) != 0) { + for (i = 0; i < TSC_READ_COUNT; i++) { + c = (unsigned char)(OPENSSL_rdtsc() & 0xFF); + rand_pool_add(pool, &c, 1, 4); + } + } + return rand_pool_entropy_available(pool); +} +#endif + +#ifdef OPENSSL_RAND_SEED_RDCPU +size_t OPENSSL_ia32_rdseed_bytes(unsigned char *buf, size_t len); +size_t OPENSSL_ia32_rdrand_bytes(unsigned char *buf, size_t len); + +extern unsigned int OPENSSL_ia32cap_P[]; + +/* + * Acquire entropy using Intel-specific cpu instructions + * + * Uses the RDSEED instruction if available, otherwise uses + * RDRAND if available. + * + * For the differences between RDSEED and RDRAND, and why RDSEED + * is the preferred choice, see https://goo.gl/oK3KcN + * + * Returns the total entropy count, if it exceeds the requested + * entropy count. Otherwise, returns an entropy count of 0. + */ +size_t rand_acquire_entropy_from_cpu(RAND_POOL *pool) +{ + size_t bytes_needed; + unsigned char *buffer; + + bytes_needed = rand_pool_bytes_needed(pool, 1 /*entropy_factor*/); + if (bytes_needed > 0) { + buffer = rand_pool_add_begin(pool, bytes_needed); + + if (buffer != NULL) { + /* Whichever comes first, use RDSEED, RDRAND or nothing */ + if ((OPENSSL_ia32cap_P[2] & (1 << 18)) != 0) { + if (OPENSSL_ia32_rdseed_bytes(buffer, bytes_needed) + == bytes_needed) { + rand_pool_add_end(pool, bytes_needed, 8 * bytes_needed); + } + } else if ((OPENSSL_ia32cap_P[1] & (1 << (62 - 32))) != 0) { + if (OPENSSL_ia32_rdrand_bytes(buffer, bytes_needed) + == bytes_needed) { + rand_pool_add_end(pool, bytes_needed, 8 * bytes_needed); + } + } else { + rand_pool_add_end(pool, 0, 0); + } + } + } + + return rand_pool_entropy_available(pool); +} +#endif + + +/* + * Implements the get_entropy() callback (see RAND_DRBG_set_callbacks()) + * + * If the DRBG has a parent, then the required amount of entropy input + * is fetched using the parent's RAND_DRBG_generate(). + * + * Otherwise, the entropy is polled from the system entropy sources + * using rand_pool_acquire_entropy(). + * + * If a random pool has been added to the DRBG using RAND_add(), then + * its entropy will be used up first. + */ +size_t rand_drbg_get_entropy(RAND_DRBG *drbg, + unsigned char **pout, + int entropy, size_t min_len, size_t max_len, + int prediction_resistance) +{ + size_t ret = 0; + size_t entropy_available = 0; + RAND_POOL *pool; + + if (drbg->parent != NULL && drbg->strength > drbg->parent->strength) { + /* + * We currently don't support the algorithm from NIST SP 800-90C + * 10.1.2 to use a weaker DRBG as source + */ + RANDerr(RAND_F_RAND_DRBG_GET_ENTROPY, RAND_R_PARENT_STRENGTH_TOO_WEAK); + return 0; + } + + if (drbg->seed_pool != NULL) { + pool = drbg->seed_pool; + pool->entropy_requested = entropy; + } else { + pool = rand_pool_new(entropy, drbg->secure, min_len, max_len); + if (pool == NULL) + return 0; + } + + if (drbg->parent != NULL) { + size_t bytes_needed = rand_pool_bytes_needed(pool, 1 /*entropy_factor*/); + unsigned char *buffer = rand_pool_add_begin(pool, bytes_needed); + + if (buffer != NULL) { + size_t bytes = 0; + + /* + * Get random data from parent. Include our address as additional input, + * in order to provide some additional distinction between different + * DRBG child instances. + * Our lock is already held, but we need to lock our parent before + * generating bits from it. (Note: taking the lock will be a no-op + * if locking if drbg->parent->lock == NULL.) + */ + rand_drbg_lock(drbg->parent); + if (RAND_DRBG_generate(drbg->parent, + buffer, bytes_needed, + prediction_resistance, + (unsigned char *)&drbg, sizeof(drbg)) != 0) + bytes = bytes_needed; + drbg->reseed_next_counter + = tsan_load(&drbg->parent->reseed_prop_counter); + rand_drbg_unlock(drbg->parent); + + rand_pool_add_end(pool, bytes, 8 * bytes); + entropy_available = rand_pool_entropy_available(pool); + } + + } else { + if (prediction_resistance) { + /* + * We don't have any entropy sources that comply with the NIST + * standard to provide prediction resistance (see NIST SP 800-90C, + * Section 5.4). + */ + RANDerr(RAND_F_RAND_DRBG_GET_ENTROPY, + RAND_R_PREDICTION_RESISTANCE_NOT_SUPPORTED); + goto err; + } + + /* Get entropy by polling system entropy sources. */ + entropy_available = rand_pool_acquire_entropy(pool); + } + + if (entropy_available > 0) { + ret = rand_pool_length(pool); + *pout = rand_pool_detach(pool); + } + + err: + if (drbg->seed_pool == NULL) + rand_pool_free(pool); + return ret; +} + +/* + * Implements the cleanup_entropy() callback (see RAND_DRBG_set_callbacks()) + * + */ +void rand_drbg_cleanup_entropy(RAND_DRBG *drbg, + unsigned char *out, size_t outlen) +{ + if (drbg->seed_pool == NULL) { + if (drbg->secure) + OPENSSL_secure_clear_free(out, outlen); + else + OPENSSL_clear_free(out, outlen); + } +} + + +/* + * Implements the get_nonce() callback (see RAND_DRBG_set_callbacks()) + * + */ +size_t rand_drbg_get_nonce(RAND_DRBG *drbg, + unsigned char **pout, + int entropy, size_t min_len, size_t max_len) +{ + size_t ret = 0; + RAND_POOL *pool; + + struct { + void * instance; + int count; + } data; + + memset(&data, 0, sizeof(data)); + pool = rand_pool_new(0, 0, min_len, max_len); + if (pool == NULL) + return 0; + + if (rand_pool_add_nonce_data(pool) == 0) + goto err; + + data.instance = drbg; + CRYPTO_atomic_add(&rand_nonce_count, 1, &data.count, rand_nonce_lock); + + if (rand_pool_add(pool, (unsigned char *)&data, sizeof(data), 0) == 0) + goto err; + + ret = rand_pool_length(pool); + *pout = rand_pool_detach(pool); + + err: + rand_pool_free(pool); + + return ret; +} + +/* + * Implements the cleanup_nonce() callback (see RAND_DRBG_set_callbacks()) + * + */ +void rand_drbg_cleanup_nonce(RAND_DRBG *drbg, + unsigned char *out, size_t outlen) +{ + OPENSSL_clear_free(out, outlen); +} + +/* + * Generate additional data that can be used for the drbg. The data does + * not need to contain entropy, but it's useful if it contains at least + * some bits that are unpredictable. + * + * Returns 0 on failure. + * + * On success it allocates a buffer at |*pout| and returns the length of + * the data. The buffer should get freed using OPENSSL_secure_clear_free(). + */ +size_t rand_drbg_get_additional_data(RAND_POOL *pool, unsigned char **pout) +{ + size_t ret = 0; + + if (rand_pool_add_additional_data(pool) == 0) + goto err; + + ret = rand_pool_length(pool); + *pout = rand_pool_detach(pool); + + err: + return ret; +} + +void rand_drbg_cleanup_additional_data(RAND_POOL *pool, unsigned char *out) +{ + rand_pool_reattach(pool, out); +} + +DEFINE_RUN_ONCE_STATIC(do_rand_init) +{ +#ifndef OPENSSL_NO_ENGINE + rand_engine_lock = CRYPTO_THREAD_lock_new(); + if (rand_engine_lock == NULL) + return 0; +#endif + + rand_meth_lock = CRYPTO_THREAD_lock_new(); + if (rand_meth_lock == NULL) + goto err1; + + rand_nonce_lock = CRYPTO_THREAD_lock_new(); + if (rand_nonce_lock == NULL) + goto err2; + + if (!rand_pool_init()) + goto err3; + + rand_inited = 1; + return 1; + +err3: + CRYPTO_THREAD_lock_free(rand_nonce_lock); + rand_nonce_lock = NULL; +err2: + CRYPTO_THREAD_lock_free(rand_meth_lock); + rand_meth_lock = NULL; +err1: +#ifndef OPENSSL_NO_ENGINE + CRYPTO_THREAD_lock_free(rand_engine_lock); + rand_engine_lock = NULL; +#endif + return 0; +} + +void rand_cleanup_int(void) +{ + const RAND_METHOD *meth = default_RAND_meth; + + if (!rand_inited) + return; + + if (meth != NULL && meth->cleanup != NULL) + meth->cleanup(); + RAND_set_rand_method(NULL); + rand_pool_cleanup(); +#ifndef OPENSSL_NO_ENGINE + CRYPTO_THREAD_lock_free(rand_engine_lock); + rand_engine_lock = NULL; +#endif + CRYPTO_THREAD_lock_free(rand_meth_lock); + rand_meth_lock = NULL; + CRYPTO_THREAD_lock_free(rand_nonce_lock); + rand_nonce_lock = NULL; + rand_inited = 0; +} + +/* + * RAND_close_seed_files() ensures that any seed file descriptors are + * closed after use. + */ +void RAND_keep_random_devices_open(int keep) +{ + if (RUN_ONCE(&rand_init, do_rand_init)) + rand_pool_keep_random_devices_open(keep); +} + +/* + * RAND_poll() reseeds the default RNG using random input + * + * The random input is obtained from polling various entropy + * sources which depend on the operating system and are + * configurable via the --with-rand-seed configure option. + */ +int RAND_poll(void) +{ + int ret = 0; + + RAND_POOL *pool = NULL; + + const RAND_METHOD *meth = RAND_get_rand_method(); + + if (meth == NULL) + return 0; + + if (meth == RAND_OpenSSL()) { + /* fill random pool and seed the master DRBG */ + RAND_DRBG *drbg = RAND_DRBG_get0_master(); + + if (drbg == NULL) + return 0; + + rand_drbg_lock(drbg); + ret = rand_drbg_restart(drbg, NULL, 0, 0); + rand_drbg_unlock(drbg); + + return ret; + + } else { + /* fill random pool and seed the current legacy RNG */ + pool = rand_pool_new(RAND_DRBG_STRENGTH, 1, + (RAND_DRBG_STRENGTH + 7) / 8, + RAND_POOL_MAX_LENGTH); + if (pool == NULL) + return 0; + + if (rand_pool_acquire_entropy(pool) == 0) + goto err; + + if (meth->add == NULL + || meth->add(rand_pool_buffer(pool), + rand_pool_length(pool), + (rand_pool_entropy(pool) / 8.0)) == 0) + goto err; + + ret = 1; + } + +err: + rand_pool_free(pool); + return ret; +} + +/* + * Allocate memory and initialize a new random pool + */ + +RAND_POOL *rand_pool_new(int entropy_requested, int secure, + size_t min_len, size_t max_len) +{ + RAND_POOL *pool = OPENSSL_zalloc(sizeof(*pool)); + size_t min_alloc_size = RAND_POOL_MIN_ALLOCATION(secure); + + if (pool == NULL) { + RANDerr(RAND_F_RAND_POOL_NEW, ERR_R_MALLOC_FAILURE); + return NULL; + } + + pool->min_len = min_len; + pool->max_len = (max_len > RAND_POOL_MAX_LENGTH) ? + RAND_POOL_MAX_LENGTH : max_len; + pool->alloc_len = min_len < min_alloc_size ? min_alloc_size : min_len; + if (pool->alloc_len > pool->max_len) + pool->alloc_len = pool->max_len; + + if (secure) + pool->buffer = OPENSSL_secure_zalloc(pool->alloc_len); + else + pool->buffer = OPENSSL_zalloc(pool->alloc_len); + + if (pool->buffer == NULL) { + RANDerr(RAND_F_RAND_POOL_NEW, ERR_R_MALLOC_FAILURE); + goto err; + } + + pool->entropy_requested = entropy_requested; + pool->secure = secure; + + return pool; + +err: + OPENSSL_free(pool); + return NULL; +} + +/* + * Attach new random pool to the given buffer + * + * This function is intended to be used only for feeding random data + * provided by RAND_add() and RAND_seed() into the <master> DRBG. + */ +RAND_POOL *rand_pool_attach(const unsigned char *buffer, size_t len, + size_t entropy) +{ + RAND_POOL *pool = OPENSSL_zalloc(sizeof(*pool)); + + if (pool == NULL) { + RANDerr(RAND_F_RAND_POOL_ATTACH, ERR_R_MALLOC_FAILURE); + return NULL; + } + + /* + * The const needs to be cast away, but attached buffers will not be + * modified (in contrary to allocated buffers which are zeroed and + * freed in the end). + */ + pool->buffer = (unsigned char *) buffer; + pool->len = len; + + pool->attached = 1; + + pool->min_len = pool->max_len = pool->alloc_len = pool->len; + pool->entropy = entropy; + + return pool; +} + +/* + * Free |pool|, securely erasing its buffer. + */ +void rand_pool_free(RAND_POOL *pool) +{ + if (pool == NULL) + return; + + /* + * Although it would be advisable from a cryptographical viewpoint, + * we are not allowed to clear attached buffers, since they are passed + * to rand_pool_attach() as `const unsigned char*`. + * (see corresponding comment in rand_pool_attach()). + */ + if (!pool->attached) { + if (pool->secure) + OPENSSL_secure_clear_free(pool->buffer, pool->alloc_len); + else + OPENSSL_clear_free(pool->buffer, pool->alloc_len); + } + + OPENSSL_free(pool); +} + +/* + * Return the |pool|'s buffer to the caller (readonly). + */ +const unsigned char *rand_pool_buffer(RAND_POOL *pool) +{ + return pool->buffer; +} + +/* + * Return the |pool|'s entropy to the caller. + */ +size_t rand_pool_entropy(RAND_POOL *pool) +{ + return pool->entropy; +} + +/* + * Return the |pool|'s buffer length to the caller. + */ +size_t rand_pool_length(RAND_POOL *pool) +{ + return pool->len; +} + +/* + * Detach the |pool| buffer and return it to the caller. + * It's the responsibility of the caller to free the buffer + * using OPENSSL_secure_clear_free() or to re-attach it + * again to the pool using rand_pool_reattach(). + */ +unsigned char *rand_pool_detach(RAND_POOL *pool) +{ + unsigned char *ret = pool->buffer; + pool->buffer = NULL; + pool->entropy = 0; + return ret; +} + +/* + * Re-attach the |pool| buffer. It is only allowed to pass + * the |buffer| which was previously detached from the same pool. + */ +void rand_pool_reattach(RAND_POOL *pool, unsigned char *buffer) +{ + pool->buffer = buffer; + OPENSSL_cleanse(pool->buffer, pool->len); + pool->len = 0; +} + +/* + * If |entropy_factor| bits contain 1 bit of entropy, how many bytes does one + * need to obtain at least |bits| bits of entropy? + */ +#define ENTROPY_TO_BYTES(bits, entropy_factor) \ + (((bits) * (entropy_factor) + 7) / 8) + + +/* + * Checks whether the |pool|'s entropy is available to the caller. + * This is the case when entropy count and buffer length are high enough. + * Returns + * + * |entropy| if the entropy count and buffer size is large enough + * 0 otherwise + */ +size_t rand_pool_entropy_available(RAND_POOL *pool) +{ + if (pool->entropy < pool->entropy_requested) + return 0; + + if (pool->len < pool->min_len) + return 0; + + return pool->entropy; +} + +/* + * Returns the (remaining) amount of entropy needed to fill + * the random pool. + */ + +size_t rand_pool_entropy_needed(RAND_POOL *pool) +{ + if (pool->entropy < pool->entropy_requested) + return pool->entropy_requested - pool->entropy; + + return 0; +} + +/* Increase the allocation size -- not usable for an attached pool */ +static int rand_pool_grow(RAND_POOL *pool, size_t len) +{ + if (len > pool->alloc_len - pool->len) { + unsigned char *p; + const size_t limit = pool->max_len / 2; + size_t newlen = pool->alloc_len; + + if (pool->attached || len > pool->max_len - pool->len) { + RANDerr(RAND_F_RAND_POOL_GROW, ERR_R_INTERNAL_ERROR); + return 0; + } + + do + newlen = newlen < limit ? newlen * 2 : pool->max_len; + while (len > newlen - pool->len); + + if (pool->secure) + p = OPENSSL_secure_zalloc(newlen); + else + p = OPENSSL_zalloc(newlen); + if (p == NULL) { + RANDerr(RAND_F_RAND_POOL_GROW, ERR_R_MALLOC_FAILURE); + return 0; + } + memcpy(p, pool->buffer, pool->len); + if (pool->secure) + OPENSSL_secure_clear_free(pool->buffer, pool->alloc_len); + else + OPENSSL_clear_free(pool->buffer, pool->alloc_len); + pool->buffer = p; + pool->alloc_len = newlen; + } + return 1; +} + +/* + * Returns the number of bytes needed to fill the pool, assuming + * the input has 1 / |entropy_factor| entropy bits per data bit. + * In case of an error, 0 is returned. + */ + +size_t rand_pool_bytes_needed(RAND_POOL *pool, unsigned int entropy_factor) +{ + size_t bytes_needed; + size_t entropy_needed = rand_pool_entropy_needed(pool); + + if (entropy_factor < 1) { + RANDerr(RAND_F_RAND_POOL_BYTES_NEEDED, RAND_R_ARGUMENT_OUT_OF_RANGE); + return 0; + } + + bytes_needed = ENTROPY_TO_BYTES(entropy_needed, entropy_factor); + + if (bytes_needed > pool->max_len - pool->len) { + /* not enough space left */ + RANDerr(RAND_F_RAND_POOL_BYTES_NEEDED, RAND_R_RANDOM_POOL_OVERFLOW); + return 0; + } + + if (pool->len < pool->min_len && + bytes_needed < pool->min_len - pool->len) + /* to meet the min_len requirement */ + bytes_needed = pool->min_len - pool->len; + + /* + * Make sure the buffer is large enough for the requested amount + * of data. This guarantees that existing code patterns where + * rand_pool_add_begin, rand_pool_add_end or rand_pool_add + * are used to collect entropy data without any error handling + * whatsoever, continue to be valid. + * Furthermore if the allocation here fails once, make sure that + * we don't fall back to a less secure or even blocking random source, + * as that could happen by the existing code patterns. + * This is not a concern for additional data, therefore that + * is not needed if rand_pool_grow fails in other places. + */ + if (!rand_pool_grow(pool, bytes_needed)) { + /* persistent error for this pool */ + pool->max_len = pool->len = 0; + return 0; + } + + return bytes_needed; +} + +/* Returns the remaining number of bytes available */ +size_t rand_pool_bytes_remaining(RAND_POOL *pool) +{ + return pool->max_len - pool->len; +} + +/* + * Add random bytes to the random pool. + * + * It is expected that the |buffer| contains |len| bytes of + * random input which contains at least |entropy| bits of + * randomness. + * + * Returns 1 if the added amount is adequate, otherwise 0 + */ +int rand_pool_add(RAND_POOL *pool, + const unsigned char *buffer, size_t len, size_t entropy) +{ + if (len > pool->max_len - pool->len) { + RANDerr(RAND_F_RAND_POOL_ADD, RAND_R_ENTROPY_INPUT_TOO_LONG); + return 0; + } + + if (pool->buffer == NULL) { + RANDerr(RAND_F_RAND_POOL_ADD, ERR_R_INTERNAL_ERROR); + return 0; + } + + if (len > 0) { + /* + * This is to protect us from accidentally passing the buffer + * returned from rand_pool_add_begin. + * The check for alloc_len makes sure we do not compare the + * address of the end of the allocated memory to something + * different, since that comparison would have an + * indeterminate result. + */ + if (pool->alloc_len > pool->len && pool->buffer + pool->len == buffer) { + RANDerr(RAND_F_RAND_POOL_ADD, ERR_R_INTERNAL_ERROR); + return 0; + } + /* + * We have that only for cases when a pool is used to collect + * additional data. + * For entropy data, as long as the allocation request stays within + * the limits given by rand_pool_bytes_needed this rand_pool_grow + * below is guaranteed to succeed, thus no allocation happens. + */ + if (!rand_pool_grow(pool, len)) + return 0; + memcpy(pool->buffer + pool->len, buffer, len); + pool->len += len; + pool->entropy += entropy; + } + + return 1; +} + +/* + * Start to add random bytes to the random pool in-place. + * + * Reserves the next |len| bytes for adding random bytes in-place + * and returns a pointer to the buffer. + * The caller is allowed to copy up to |len| bytes into the buffer. + * If |len| == 0 this is considered a no-op and a NULL pointer + * is returned without producing an error message. + * + * After updating the buffer, rand_pool_add_end() needs to be called + * to finish the update operation (see next comment). + */ +unsigned char *rand_pool_add_begin(RAND_POOL *pool, size_t len) +{ + if (len == 0) + return NULL; + + if (len > pool->max_len - pool->len) { + RANDerr(RAND_F_RAND_POOL_ADD_BEGIN, RAND_R_RANDOM_POOL_OVERFLOW); + return NULL; + } + + if (pool->buffer == NULL) { + RANDerr(RAND_F_RAND_POOL_ADD_BEGIN, ERR_R_INTERNAL_ERROR); + return NULL; + } + + /* + * As long as the allocation request stays within the limits given + * by rand_pool_bytes_needed this rand_pool_grow below is guaranteed + * to succeed, thus no allocation happens. + * We have that only for cases when a pool is used to collect + * additional data. Then the buffer might need to grow here, + * and of course the caller is responsible to check the return + * value of this function. + */ + if (!rand_pool_grow(pool, len)) + return NULL; + + return pool->buffer + pool->len; +} + +/* + * Finish to add random bytes to the random pool in-place. + * + * Finishes an in-place update of the random pool started by + * rand_pool_add_begin() (see previous comment). + * It is expected that |len| bytes of random input have been added + * to the buffer which contain at least |entropy| bits of randomness. + * It is allowed to add less bytes than originally reserved. + */ +int rand_pool_add_end(RAND_POOL *pool, size_t len, size_t entropy) +{ + if (len > pool->alloc_len - pool->len) { + RANDerr(RAND_F_RAND_POOL_ADD_END, RAND_R_RANDOM_POOL_OVERFLOW); + return 0; + } + + if (len > 0) { + pool->len += len; + pool->entropy += entropy; + } + + return 1; +} + +int RAND_set_rand_method(const RAND_METHOD *meth) +{ + if (!RUN_ONCE(&rand_init, do_rand_init)) + return 0; + + CRYPTO_THREAD_write_lock(rand_meth_lock); +#ifndef OPENSSL_NO_ENGINE + ENGINE_finish(funct_ref); + funct_ref = NULL; +#endif + default_RAND_meth = meth; + CRYPTO_THREAD_unlock(rand_meth_lock); + return 1; +} + +const RAND_METHOD *RAND_get_rand_method(void) +{ + const RAND_METHOD *tmp_meth = NULL; + + if (!RUN_ONCE(&rand_init, do_rand_init)) + return NULL; + + CRYPTO_THREAD_write_lock(rand_meth_lock); + if (default_RAND_meth == NULL) { +#ifndef OPENSSL_NO_ENGINE + ENGINE *e; + + /* If we have an engine that can do RAND, use it. */ + if ((e = ENGINE_get_default_RAND()) != NULL + && (tmp_meth = ENGINE_get_RAND(e)) != NULL) { + funct_ref = e; + default_RAND_meth = tmp_meth; + } else { + ENGINE_finish(e); + default_RAND_meth = &rand_meth; + } +#else + default_RAND_meth = &rand_meth; +#endif + } + tmp_meth = default_RAND_meth; + CRYPTO_THREAD_unlock(rand_meth_lock); + return tmp_meth; +} + +#ifndef OPENSSL_NO_ENGINE +int RAND_set_rand_engine(ENGINE *engine) +{ + const RAND_METHOD *tmp_meth = NULL; + + if (!RUN_ONCE(&rand_init, do_rand_init)) + return 0; + + if (engine != NULL) { + if (!ENGINE_init(engine)) + return 0; + tmp_meth = ENGINE_get_RAND(engine); + if (tmp_meth == NULL) { + ENGINE_finish(engine); + return 0; + } + } + CRYPTO_THREAD_write_lock(rand_engine_lock); + /* This function releases any prior ENGINE so call it first */ + RAND_set_rand_method(tmp_meth); + funct_ref = engine; + CRYPTO_THREAD_unlock(rand_engine_lock); + return 1; +} +#endif + +void RAND_seed(const void *buf, int num) +{ + const RAND_METHOD *meth = RAND_get_rand_method(); + + if (meth != NULL && meth->seed != NULL) + meth->seed(buf, num); +} + +void RAND_add(const void *buf, int num, double randomness) +{ + const RAND_METHOD *meth = RAND_get_rand_method(); + + if (meth != NULL && meth->add != NULL) + meth->add(buf, num, randomness); +} + +/* + * This function is not part of RAND_METHOD, so if we're not using + * the default method, then just call RAND_bytes(). Otherwise make + * sure we're instantiated and use the private DRBG. + */ +int RAND_priv_bytes(unsigned char *buf, int num) +{ + const RAND_METHOD *meth = RAND_get_rand_method(); + RAND_DRBG *drbg; + + if (meth != NULL && meth != RAND_OpenSSL()) + return RAND_bytes(buf, num); + + drbg = RAND_DRBG_get0_private(); + if (drbg != NULL) + return RAND_DRBG_bytes(drbg, buf, num); + + return 0; +} + +int RAND_bytes(unsigned char *buf, int num) +{ + const RAND_METHOD *meth = RAND_get_rand_method(); + + if (meth != NULL && meth->bytes != NULL) + return meth->bytes(buf, num); + RANDerr(RAND_F_RAND_BYTES, RAND_R_FUNC_NOT_IMPLEMENTED); + return -1; +} + +#if OPENSSL_API_COMPAT < 0x10100000L +int RAND_pseudo_bytes(unsigned char *buf, int num) +{ + const RAND_METHOD *meth = RAND_get_rand_method(); + + if (meth != NULL && meth->pseudorand != NULL) + return meth->pseudorand(buf, num); + RANDerr(RAND_F_RAND_PSEUDO_BYTES, RAND_R_FUNC_NOT_IMPLEMENTED); + return -1; +} +#endif + +int RAND_status(void) +{ + const RAND_METHOD *meth = RAND_get_rand_method(); + + if (meth != NULL && meth->status != NULL) + return meth->status(); + return 0; +} |