X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=crypto%2Frand%2Fmd_rand.c;h=a7af9f9d8671bad10c4b73c479b55095ffe3cf53;hb=0971432f6f6d8b40d797133621809bd31eb7bf4e;hp=837947e8a622c90307c1f12336f987c424cddcaf;hpb=d6ade7422ab60259c1d7b825ee0ff9a5361c7f42;p=oweals%2Fopenssl.git diff --git a/crypto/rand/md_rand.c b/crypto/rand/md_rand.c index 837947e8a6..a7af9f9d86 100644 --- a/crypto/rand/md_rand.c +++ b/crypto/rand/md_rand.c @@ -5,21 +5,21 @@ * This package is an SSL implementation written * by Eric Young (eay@cryptsoft.com). * The implementation was written so as to conform with Netscapes SSL. - * + * * This library is free for commercial and non-commercial use as long as * the following conditions are aheared to. The following conditions * apply to all code found in this distribution, be it the RC4, RSA, * lhash, DES, etc., code; not just the SSL code. The SSL documentation * included with this distribution is covered by the same copyright terms * except that the holder is Tim Hudson (tjh@cryptsoft.com). - * + * * Copyright remains Eric Young's, and as such any Copyright notices in * the code are not to be removed. * If this package is used in a product, Eric Young should be given attribution * as the author of the parts of the library used. * This can be in the form of a textual message at program startup or * in documentation (online or textual) provided with the package. - * + * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: @@ -34,10 +34,10 @@ * Eric Young (eay@cryptsoft.com)" * The word 'cryptographic' can be left out if the rouines from the library * being used are not cryptographic related :-). - * 4. If you include any Windows specific code (or a derivative thereof) from + * 4. If you include any Windows specific code (or a derivative thereof) from * the apps directory (application code) you must include an acknowledgement: * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" - * + * * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE @@ -49,21 +49,21 @@ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. - * + * * The licence and distribution terms for any publically available version or * derivative of this code cannot be changed. i.e. this code cannot simply be * copied and put under another distribution licence * [including the GNU Public Licence.] */ /* ==================================================================== - * Copyright (c) 1998-2000 The OpenSSL Project. All rights reserved. + * Copyright (c) 1998-2001 The OpenSSL Project. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. + * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in @@ -109,9 +109,11 @@ * */ +#define OPENSSL_FIPSEVP + #ifdef MD_RAND_DEBUG # ifndef NDEBUG -# define NDEBUG +# define NDEBUG # endif #endif @@ -119,392 +121,496 @@ #include #include -#include "openssl/e_os.h" +#include "e_os.h" +#include #include #include "rand_lcl.h" -#include #include #ifdef BN_DEBUG # define PREDICT #endif -/* #define PREDICT 1 */ +/* #define PREDICT 1 */ -#define STATE_SIZE 1023 -static int state_num=0,state_index=0; -static unsigned char state[STATE_SIZE+MD_DIGEST_LENGTH]; +#define STATE_SIZE 1023 +static size_t state_num = 0, state_index = 0; +static unsigned char state[STATE_SIZE + MD_DIGEST_LENGTH]; static unsigned char md[MD_DIGEST_LENGTH]; -static long md_count[2]={0,0}; -static double entropy=0; -static int initialized=0; +static long md_count[2] = { 0, 0 }; -/* This should be set to 1 only when ssleay_rand_add() is called inside - an already locked state, so it doesn't try to lock and thereby cause - a hang. And it should always be reset back to 0 before unlocking. */ -static int add_do_not_lock=0; +static double entropy = 0; +static int initialized = 0; + +static unsigned int crypto_lock_rand = 0; /* may be set only when a thread + * holds CRYPTO_LOCK_RAND (to + * prevent double locking) */ +/* access to lockin_thread is synchronized by CRYPTO_LOCK_RAND2 */ +/* valid iff crypto_lock_rand is set */ +static CRYPTO_THREADID locking_threadid; #ifdef PREDICT -int rand_predictable=0; +int rand_predictable = 0; #endif -const char *RAND_version="RAND" OPENSSL_VERSION_PTEXT; +const char RAND_version[] = "RAND" OPENSSL_VERSION_PTEXT; static void ssleay_rand_cleanup(void); static void ssleay_rand_seed(const void *buf, int num); static void ssleay_rand_add(const void *buf, int num, double add_entropy); -static int ssleay_rand_bytes(unsigned char *buf, int num); +static int ssleay_rand_nopseudo_bytes(unsigned char *buf, int num); static int ssleay_rand_pseudo_bytes(unsigned char *buf, int num); static int ssleay_rand_status(void); -RAND_METHOD rand_ssleay_meth={ - ssleay_rand_seed, - ssleay_rand_bytes, - ssleay_rand_cleanup, - ssleay_rand_add, - ssleay_rand_pseudo_bytes, - ssleay_rand_status - }; +RAND_METHOD rand_ssleay_meth = { + ssleay_rand_seed, + ssleay_rand_nopseudo_bytes, + ssleay_rand_cleanup, + ssleay_rand_add, + ssleay_rand_pseudo_bytes, + ssleay_rand_status +}; RAND_METHOD *RAND_SSLeay(void) - { - return(&rand_ssleay_meth); - } +{ + return (&rand_ssleay_meth); +} static void ssleay_rand_cleanup(void) - { - memset(state,0,sizeof(state)); - state_num=0; - state_index=0; - memset(md,0,MD_DIGEST_LENGTH); - md_count[0]=0; - md_count[1]=0; - entropy=0; - } +{ + OPENSSL_cleanse(state, sizeof(state)); + state_num = 0; + state_index = 0; + OPENSSL_cleanse(md, MD_DIGEST_LENGTH); + md_count[0] = 0; + md_count[1] = 0; + entropy = 0; + initialized = 0; +} static void ssleay_rand_add(const void *buf, int num, double add) - { - int i,j,k,st_idx; - long md_c[2]; - unsigned char local_md[MD_DIGEST_LENGTH]; - MD_CTX m; - - /* - * (Based on the rand(3) manpage) - * - * The input is chopped up into units of 20 bytes (or less for - * the last block). Each of these blocks is run through the hash - * function as follows: The data passed to the hash function - * is the current 'md', the same number of bytes from the 'state' - * (the location determined by in incremented looping index) as - * the current 'block', the new key data 'block', and 'count' - * (which is incremented after each use). - * The result of this is kept in 'md' and also xored into the - * 'state' at the same locations that were used as input into the - * hash function. - */ - - if (!add_do_not_lock) CRYPTO_w_lock(CRYPTO_LOCK_RAND); - st_idx=state_index; - - /* use our own copies of the counters so that even - * if a concurrent thread seeds with exactly the - * same data and uses the same subarray there's _some_ - * difference */ - md_c[0] = md_count[0]; - md_c[1] = md_count[1]; - - memcpy(local_md, md, sizeof md); - - /* state_index <= state_num <= STATE_SIZE */ - state_index += num; - if (state_index >= STATE_SIZE) - { - state_index%=STATE_SIZE; - state_num=STATE_SIZE; - } - else if (state_num < STATE_SIZE) - { - if (state_index > state_num) - state_num=state_index; - } - /* state_index <= state_num <= STATE_SIZE */ - - /* state[st_idx], ..., state[(st_idx + num - 1) % STATE_SIZE] - * are what we will use now, but other threads may use them - * as well */ - - md_count[1] += (num / MD_DIGEST_LENGTH) + (num % MD_DIGEST_LENGTH > 0); - - if (!add_do_not_lock) CRYPTO_w_unlock(CRYPTO_LOCK_RAND); - - for (i=0; i MD_DIGEST_LENGTH)?MD_DIGEST_LENGTH:j; - - MD_Init(&m); - MD_Update(&m,local_md,MD_DIGEST_LENGTH); - k=(st_idx+j)-STATE_SIZE; - if (k > 0) - { - MD_Update(&m,&(state[st_idx]),j-k); - MD_Update(&m,&(state[0]),k); - } - else - MD_Update(&m,&(state[st_idx]),j); - - MD_Update(&m,buf,j); - MD_Update(&m,(unsigned char *)&(md_c[0]),sizeof(md_c)); - MD_Final(local_md,&m); - md_c[1]++; - - buf=(const char *)buf + j; - - for (k=0; k= STATE_SIZE) - st_idx=0; - } - } - memset((char *)&m,0,sizeof(m)); - - if (!add_do_not_lock) CRYPTO_w_lock(CRYPTO_LOCK_RAND); - /* Don't just copy back local_md into md -- this could mean that - * other thread's seeding remains without effect (except for - * the incremented counter). By XORing it we keep at least as - * much entropy as fits into md. */ - for (k = 0; k < sizeof md; k++) - { - md[k] ^= local_md[k]; - } - if (entropy < ENTROPY_NEEDED) /* stop counting when we have enough */ - entropy += add; - if (!add_do_not_lock) CRYPTO_w_unlock(CRYPTO_LOCK_RAND); - -#if !defined(THREADS) && !defined(WIN32) - assert(md_c[1] == md_count[1]); +{ + int i, j, k, st_idx; + long md_c[2]; + unsigned char local_md[MD_DIGEST_LENGTH]; + EVP_MD_CTX m; + int do_not_lock; + + if (!num) + return; + + /* + * (Based on the rand(3) manpage) + * + * The input is chopped up into units of 20 bytes (or less for + * the last block). Each of these blocks is run through the hash + * function as follows: The data passed to the hash function + * is the current 'md', the same number of bytes from the 'state' + * (the location determined by in incremented looping index) as + * the current 'block', the new key data 'block', and 'count' + * (which is incremented after each use). + * The result of this is kept in 'md' and also xored into the + * 'state' at the same locations that were used as input into the + * hash function. + */ + + /* check if we already have the lock */ + if (crypto_lock_rand) { + CRYPTO_THREADID cur; + CRYPTO_THREADID_current(&cur); + CRYPTO_r_lock(CRYPTO_LOCK_RAND2); + do_not_lock = !CRYPTO_THREADID_cmp(&locking_threadid, &cur); + CRYPTO_r_unlock(CRYPTO_LOCK_RAND2); + } else + do_not_lock = 0; + + if (!do_not_lock) + CRYPTO_w_lock(CRYPTO_LOCK_RAND); + st_idx = state_index; + + /* + * use our own copies of the counters so that even if a concurrent thread + * seeds with exactly the same data and uses the same subarray there's + * _some_ difference + */ + md_c[0] = md_count[0]; + md_c[1] = md_count[1]; + + memcpy(local_md, md, sizeof(md)); + + /* state_index <= state_num <= STATE_SIZE */ + state_index += num; + if (state_index >= STATE_SIZE) { + state_index %= STATE_SIZE; + state_num = STATE_SIZE; + } else if (state_num < STATE_SIZE) { + if (state_index > state_num) + state_num = state_index; + } + /* state_index <= state_num <= STATE_SIZE */ + + /* + * state[st_idx], ..., state[(st_idx + num - 1) % STATE_SIZE] are what we + * will use now, but other threads may use them as well + */ + + md_count[1] += (num / MD_DIGEST_LENGTH) + (num % MD_DIGEST_LENGTH > 0); + + if (!do_not_lock) + CRYPTO_w_unlock(CRYPTO_LOCK_RAND); + + EVP_MD_CTX_init(&m); + for (i = 0; i < num; i += MD_DIGEST_LENGTH) { + j = (num - i); + j = (j > MD_DIGEST_LENGTH) ? MD_DIGEST_LENGTH : j; + + if (!MD_Init(&m) || + !MD_Update(&m, local_md, MD_DIGEST_LENGTH)) + goto err; + k = (st_idx + j) - STATE_SIZE; + if (k > 0) { + if (!MD_Update(&m, &(state[st_idx]), j - k) || + !MD_Update(&m, &(state[0]), k)) + goto err; + } else + if (!MD_Update(&m, &(state[st_idx]), j)) + goto err; + + /* DO NOT REMOVE THE FOLLOWING CALL TO MD_Update()! */ + if (!MD_Update(&m, buf, j)) + goto err; + /* + * We know that line may cause programs such as purify and valgrind + * to complain about use of uninitialized data. The problem is not, + * it's with the caller. Removing that line will make sure you get + * really bad randomness and thereby other problems such as very + * insecure keys. + */ + + if (!MD_Update(&m, (unsigned char *)&(md_c[0]), sizeof(md_c)) || + !MD_Final(&m, local_md)) + goto err; + md_c[1]++; + + buf = (const char *)buf + j; + + for (k = 0; k < j; k++) { + /* + * Parallel threads may interfere with this, but always each byte + * of the new state is the XOR of some previous value of its and + * local_md (itermediate values may be lost). Alway using locking + * could hurt performance more than necessary given that + * conflicts occur only when the total seeding is longer than the + * random state. + */ + state[st_idx++] ^= local_md[k]; + if (st_idx >= STATE_SIZE) + st_idx = 0; + } + } + + if (!do_not_lock) + CRYPTO_w_lock(CRYPTO_LOCK_RAND); + /* + * Don't just copy back local_md into md -- this could mean that other + * thread's seeding remains without effect (except for the incremented + * counter). By XORing it we keep at least as much entropy as fits into + * md. + */ + for (k = 0; k < (int)sizeof(md); k++) { + md[k] ^= local_md[k]; + } + if (entropy < ENTROPY_NEEDED) /* stop counting when we have enough */ + entropy += add; + if (!do_not_lock) + CRYPTO_w_unlock(CRYPTO_LOCK_RAND); + +#if !defined(OPENSSL_THREADS) && !defined(OPENSSL_SYS_WIN32) + assert(md_c[1] == md_count[1]); #endif - } + + err: + EVP_MD_CTX_cleanup(&m); +} static void ssleay_rand_seed(const void *buf, int num) - { - ssleay_rand_add(buf, num, num); - } - -static int ssleay_rand_bytes(unsigned char *buf, int num) - { - static volatile int stirred_pool = 0; - int i,j,k,st_num,st_idx; - int ok; - long md_c[2]; - unsigned char local_md[MD_DIGEST_LENGTH]; - MD_CTX m; +{ + ssleay_rand_add(buf, num, (double)num); +} + +int ssleay_rand_bytes(unsigned char *buf, int num, int pseudo, int lock) +{ + static volatile int stirred_pool = 0; + int i, j, k; + size_t num_ceil, st_idx, st_num; + int ok; + long md_c[2]; + unsigned char local_md[MD_DIGEST_LENGTH]; + EVP_MD_CTX m; #ifndef GETPID_IS_MEANINGLESS - pid_t curr_pid = getpid(); + pid_t curr_pid = getpid(); #endif - int do_stir_pool = 0; + int do_stir_pool = 0; #ifdef PREDICT - if (rand_predictable) - { - static unsigned char val=0; - - for (i=0; i= ENTROPY_NEEDED); - if (!ok) - { - /* If the PRNG state is not yet unpredictable, then seeing - * the PRNG output may help attackers to determine the new - * state; thus we have to decrease the entropy estimate. - * Once we've had enough initial seeding we don't bother to - * adjust the entropy count, though, because we're not ambitious - * to provide *information-theoretic* randomness. - * - * NOTE: This approach fails if the program forks before - * we have enough entropy. Entropy should be collected - * in a separate input pool and be transferred to the - * output pool only when the entropy limit has been reached. - */ - entropy -= num; - if (entropy < 0) - entropy = 0; - } - - if (do_stir_pool) - { - /* Our output function chains only half of 'md', so we better - * make sure that the required entropy gets 'evenly distributed' - * through 'state', our randomness pool. The input function - * (ssleay_rand_add) chains all of 'md', which makes it more - * suitable for this purpose. - */ - - int n = STATE_SIZE; /* so that the complete pool gets accessed */ - while (n > 0) - { + if (num <= 0) + return 1; + + EVP_MD_CTX_init(&m); + /* round upwards to multiple of MD_DIGEST_LENGTH/2 */ + num_ceil = + (1 + (num - 1) / (MD_DIGEST_LENGTH / 2)) * (MD_DIGEST_LENGTH / 2); + + /* + * (Based on the rand(3) manpage:) + * + * For each group of 10 bytes (or less), we do the following: + * + * Input into the hash function the local 'md' (which is initialized from + * the global 'md' before any bytes are generated), the bytes that are to + * be overwritten by the random bytes, and bytes from the 'state' + * (incrementing looping index). From this digest output (which is kept + * in 'md'), the top (up to) 10 bytes are returned to the caller and the + * bottom 10 bytes are xored into the 'state'. + * + * Finally, after we have finished 'num' random bytes for the + * caller, 'count' (which is incremented) and the local and global 'md' + * are fed into the hash function and the results are kept in the + * global 'md'. + */ + if (lock) + CRYPTO_w_lock(CRYPTO_LOCK_RAND); + + /* prevent ssleay_rand_bytes() from trying to obtain the lock again */ + CRYPTO_w_lock(CRYPTO_LOCK_RAND2); + CRYPTO_THREADID_current(&locking_threadid); + CRYPTO_w_unlock(CRYPTO_LOCK_RAND2); + crypto_lock_rand = 1; + + if (!initialized) { + RAND_poll(); + initialized = 1; + } + + if (!stirred_pool) + do_stir_pool = 1; + + ok = (entropy >= ENTROPY_NEEDED); + if (!ok) { + /* + * If the PRNG state is not yet unpredictable, then seeing the PRNG + * output may help attackers to determine the new state; thus we have + * to decrease the entropy estimate. Once we've had enough initial + * seeding we don't bother to adjust the entropy count, though, + * because we're not ambitious to provide *information-theoretic* + * randomness. NOTE: This approach fails if the program forks before + * we have enough entropy. Entropy should be collected in a separate + * input pool and be transferred to the output pool only when the + * entropy limit has been reached. + */ + entropy -= num; + if (entropy < 0) + entropy = 0; + } + + if (do_stir_pool) { + /* + * In the output function only half of 'md' remains secret, so we + * better make sure that the required entropy gets 'evenly + * distributed' through 'state', our randomness pool. The input + * function (ssleay_rand_add) chains all of 'md', which makes it more + * suitable for this purpose. + */ + + int n = STATE_SIZE; /* so that the complete pool gets accessed */ + while (n > 0) { #if MD_DIGEST_LENGTH > 20 # error "Please adjust DUMMY_SEED." #endif #define DUMMY_SEED "...................." /* at least MD_DIGEST_LENGTH */ - /* Note that the seed does not matter, it's just that - * ssleay_rand_add expects to have something to hash. */ - ssleay_rand_add(DUMMY_SEED, MD_DIGEST_LENGTH, 0.0); - n -= MD_DIGEST_LENGTH; - } - if (ok) - stirred_pool = 1; - } - - st_idx=state_index; - st_num=state_num; - md_c[0] = md_count[0]; - md_c[1] = md_count[1]; - memcpy(local_md, md, sizeof md); - - state_index+=num; - if (state_index > state_num) - state_index %= state_num; - - /* state[st_idx], ..., state[(st_idx + num - 1) % st_num] - * are now ours (but other threads may use them too) */ - - md_count[0] += 1; - - add_do_not_lock = 0; /* If this would ever be forgotten, we can - expect any evil god to eat our souls. */ - CRYPTO_w_unlock(CRYPTO_LOCK_RAND); - - while (num > 0) - { - j=(num >= MD_DIGEST_LENGTH/2)?MD_DIGEST_LENGTH/2:num; - num-=j; - MD_Init(&m); + /* + * Note that the seed does not matter, it's just that + * ssleay_rand_add expects to have something to hash. + */ + ssleay_rand_add(DUMMY_SEED, MD_DIGEST_LENGTH, 0.0); + n -= MD_DIGEST_LENGTH; + } + if (ok) + stirred_pool = 1; + } + + st_idx = state_index; + st_num = state_num; + md_c[0] = md_count[0]; + md_c[1] = md_count[1]; + memcpy(local_md, md, sizeof(md)); + + state_index += num_ceil; + if (state_index > state_num) + state_index %= state_num; + + /* + * state[st_idx], ..., state[(st_idx + num_ceil - 1) % st_num] are now + * ours (but other threads may use them too) + */ + + md_count[0] += 1; + + /* before unlocking, we must clear 'crypto_lock_rand' */ + crypto_lock_rand = 0; + if (lock) + CRYPTO_w_unlock(CRYPTO_LOCK_RAND); + + while (num > 0) { + /* num_ceil -= MD_DIGEST_LENGTH/2 */ + j = (num >= MD_DIGEST_LENGTH / 2) ? MD_DIGEST_LENGTH / 2 : num; + num -= j; + if (!MD_Init(&m)) + goto err; #ifndef GETPID_IS_MEANINGLESS - if (curr_pid) /* just in the first iteration to save time */ - { - MD_Update(&m,(unsigned char*)&curr_pid,sizeof curr_pid); - curr_pid = 0; - } + if (curr_pid) { /* just in the first iteration to save time */ + if (!MD_Update(&m, (unsigned char *)&curr_pid, sizeof(curr_pid))) + goto err; + curr_pid = 0; + } #endif - MD_Update(&m,&(local_md[MD_DIGEST_LENGTH/2]),MD_DIGEST_LENGTH/2); - MD_Update(&m,(unsigned char *)&(md_c[0]),sizeof(md_c)); -#ifndef PURIFY - MD_Update(&m,buf,j); /* purify complains */ + if (!MD_Update(&m, local_md, MD_DIGEST_LENGTH) || + !MD_Update(&m, (unsigned char *)&(md_c[0]), sizeof(md_c))) + goto err; + +#ifndef PURIFY /* purify complains */ + /* + * The following line uses the supplied buffer as a small source of + * entropy: since this buffer is often uninitialised it may cause + * programs such as purify or valgrind to complain. So for those + * builds it is not used: the removal of such a small source of + * entropy has negligible impact on security. + */ + if (!MD_Update(&m, buf, j)) + goto err; #endif - k=(st_idx+j)-st_num; - if (k > 0) - { - MD_Update(&m,&(state[st_idx]),j-k); - MD_Update(&m,&(state[0]),k); - } - else - MD_Update(&m,&(state[st_idx]),j); - MD_Final(local_md,&m); - - for (i=0; i= st_num) - st_idx=0; - } - } - - MD_Init(&m); - MD_Update(&m,(unsigned char *)&(md_c[0]),sizeof(md_c)); - MD_Update(&m,local_md,MD_DIGEST_LENGTH); - CRYPTO_w_lock(CRYPTO_LOCK_RAND); - MD_Update(&m,md,MD_DIGEST_LENGTH); - MD_Final(md,&m); - CRYPTO_w_unlock(CRYPTO_LOCK_RAND); - - memset(&m,0,sizeof(m)); - if (ok) - return(1); - else - { - RANDerr(RAND_F_SSLEAY_RAND_BYTES,RAND_R_PRNG_NOT_SEEDED); - ERR_add_error_data(1, "You need to read the OpenSSL FAQ, " - "http://www.openssl.org/support/faq.html"); - return(0); - } - } - -/* pseudo-random bytes that are guaranteed to be unique but not - unpredictable */ -static int ssleay_rand_pseudo_bytes(unsigned char *buf, int num) - { - int ret, err; - - ret = RAND_bytes(buf, num); - if (ret == 0) - { - err = ERR_peek_error(); - if (ERR_GET_LIB(err) == ERR_LIB_RAND && - ERR_GET_REASON(err) == RAND_R_PRNG_NOT_SEEDED) - (void)ERR_get_error(); - } - return (ret); - } - -static int ssleay_rand_status(void) - { - int ret; - - if (!initialized) - RAND_poll(); - CRYPTO_w_lock(CRYPTO_LOCK_RAND); - initialized = 1; - ret = entropy >= ENTROPY_NEEDED; - CRYPTO_w_unlock(CRYPTO_LOCK_RAND); + k = (st_idx + MD_DIGEST_LENGTH / 2) - st_num; + if (k > 0) { + if (!MD_Update(&m, &(state[st_idx]), MD_DIGEST_LENGTH / 2 - k) || + !MD_Update(&m, &(state[0]), k)) + goto err; + } else { + if (!MD_Update(&m, &(state[st_idx]), MD_DIGEST_LENGTH / 2)) + goto err; + } + if (!MD_Final(&m, local_md)) + goto err; + + for (i = 0; i < MD_DIGEST_LENGTH / 2; i++) { + /* may compete with other threads */ + state[st_idx++] ^= local_md[i]; + if (st_idx >= st_num) + st_idx = 0; + if (i < j) + *(buf++) = local_md[i + MD_DIGEST_LENGTH / 2]; + } + } + + if (!MD_Init(&m) || + !MD_Update(&m, (unsigned char *)&(md_c[0]), sizeof(md_c)) || + !MD_Update(&m, local_md, MD_DIGEST_LENGTH)) + goto err; + if (lock) + CRYPTO_w_lock(CRYPTO_LOCK_RAND); + if (!MD_Update(&m, md, MD_DIGEST_LENGTH) || + !MD_Final(&m, md)) { + if (lock) + CRYPTO_w_unlock(CRYPTO_LOCK_RAND); + goto err; + } + if (lock) + CRYPTO_w_unlock(CRYPTO_LOCK_RAND); + + EVP_MD_CTX_cleanup(&m); + if (ok) + return (1); + else if (pseudo) + return 0; + else { + RANDerr(RAND_F_SSLEAY_RAND_BYTES, RAND_R_PRNG_NOT_SEEDED); + ERR_add_error_data(1, "You need to read the OpenSSL FAQ, " + "http://www.openssl.org/support/faq.html"); + return (0); + } + + err: + EVP_MD_CTX_cleanup(&m); + return (0); +} + +static int ssleay_rand_nopseudo_bytes(unsigned char *buf, int num) +{ + return ssleay_rand_bytes(buf, num, 0, 1); +} + +/* + * pseudo-random bytes that are guaranteed to be unique but not unpredictable + */ +static int ssleay_rand_pseudo_bytes(unsigned char *buf, int num) +{ + return ssleay_rand_bytes(buf, num, 1, 1); +} - return ret; - } +static int ssleay_rand_status(void) +{ + CRYPTO_THREADID cur; + int ret; + int do_not_lock; + + CRYPTO_THREADID_current(&cur); + /* + * check if we already have the lock (could happen if a RAND_poll() + * implementation calls RAND_status()) + */ + if (crypto_lock_rand) { + CRYPTO_r_lock(CRYPTO_LOCK_RAND2); + do_not_lock = !CRYPTO_THREADID_cmp(&locking_threadid, &cur); + CRYPTO_r_unlock(CRYPTO_LOCK_RAND2); + } else + do_not_lock = 0; + + if (!do_not_lock) { + CRYPTO_w_lock(CRYPTO_LOCK_RAND); + + /* + * prevent ssleay_rand_bytes() from trying to obtain the lock again + */ + CRYPTO_w_lock(CRYPTO_LOCK_RAND2); + CRYPTO_THREADID_cpy(&locking_threadid, &cur); + CRYPTO_w_unlock(CRYPTO_LOCK_RAND2); + crypto_lock_rand = 1; + } + + if (!initialized) { + RAND_poll(); + initialized = 1; + } + + ret = entropy >= ENTROPY_NEEDED; + + if (!do_not_lock) { + /* before unlocking, we must clear 'crypto_lock_rand' */ + crypto_lock_rand = 0; + + CRYPTO_w_unlock(CRYPTO_LOCK_RAND); + } + + return ret; +}