--- /dev/null
+/* crypto/rand/md_rand.c */
+/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
+ * All rights reserved.
+ *
+ * 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:
+ * 1. Redistributions of source code must retain the copyright
+ * 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 the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * "This product includes cryptographic software written by
+ * 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
+ * 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
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * 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) 1998-2001 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.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * 3. All advertising materials mentioning features or use of this
+ * software must display the following acknowledgment:
+ * "This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ * endorse or promote products derived from this software without
+ * prior written permission. For written permission, please contact
+ * openssl-core@openssl.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ * nor may "OpenSSL" appear in their names without prior written
+ * permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ * acknowledgment:
+ * "This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT 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.
+ * ====================================================================
+ *
+ * This product includes cryptographic software written by Eric Young
+ * (eay@cryptsoft.com). This product includes software written by Tim
+ * Hudson (tjh@cryptsoft.com).
+ *
+ */
+
+#define OPENSSL_FIPSEVP
+
+#ifdef MD_RAND_DEBUG
+# ifndef NDEBUG
+# define NDEBUG
+# endif
+#endif
+
+#include <assert.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "e_os.h"
+
+#include <openssl/crypto.h>
+#include <openssl/rand.h>
+#include "rand_lcl.h"
+
+#include <openssl/err.h>
+
+#ifdef BN_DEBUG
+# define PREDICT
+#endif
+
+/* #define PREDICT 1 */
+
+#define STATE_SIZE 1023
+static int 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 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 */
+static CRYPTO_THREADID locking_threadid; /* valid iff crypto_lock_rand is set */
+
+
+#ifdef PREDICT
+int rand_predictable=0;
+#endif
+
+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_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_nopseudo_bytes,
+ ssleay_rand_cleanup,
+ ssleay_rand_add,
+ ssleay_rand_pseudo_bytes,
+ ssleay_rand_status
+ };
+
+RAND_METHOD *RAND_SSLeay(void)
+ {
+ return(&rand_ssleay_meth);
+ }
+
+static void ssleay_rand_cleanup(void)
+ {
+ 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];
+ 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;
+
+ 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);
+
+ /* DO NOT REMOVE THE FOLLOWING CALL TO MD_Update()! */
+ MD_Update(&m,buf,j);
+ /* 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. */
+
+ MD_Update(&m,(unsigned char *)&(md_c[0]),sizeof(md_c));
+ MD_Final(&m,local_md);
+ 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;
+ }
+ }
+ EVP_MD_CTX_cleanup(&m);
+
+ 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
+ }
+
+static void ssleay_rand_seed(const void *buf, int num)
+ {
+ 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,st_num,st_idx;
+ int num_ceil;
+ 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();
+#endif
+ int do_stir_pool = 0;
+
+#ifdef PREDICT
+ if (rand_predictable)
+ {
+ static unsigned char val=0;
+
+ for (i=0; i<num; i++)
+ buf[i]=val++;
+ return(1);
+ }
+#endif
+
+ 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_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;
+ MD_Init(&m);
+#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;
+ }
+#endif
+ MD_Update(&m,local_md,MD_DIGEST_LENGTH);
+ MD_Update(&m,(unsigned char *)&(md_c[0]),sizeof(md_c));
+
+#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.
+ */
+ MD_Update(&m,buf,j);
+#endif
+
+ k=(st_idx+MD_DIGEST_LENGTH/2)-st_num;
+ if (k > 0)
+ {
+ MD_Update(&m,&(state[st_idx]),MD_DIGEST_LENGTH/2-k);
+ MD_Update(&m,&(state[0]),k);
+ }
+ else
+ MD_Update(&m,&(state[st_idx]),MD_DIGEST_LENGTH/2);
+ MD_Final(&m,local_md);
+
+ for (i=0; i<MD_DIGEST_LENGTH/2; i++)
+ {
+ state[st_idx++]^=local_md[i]; /* may compete with other threads */
+ if (st_idx >= st_num)
+ st_idx=0;
+ if (i < j)
+ *(buf++)=local_md[i+MD_DIGEST_LENGTH/2];
+ }
+ }
+
+ MD_Init(&m);
+ MD_Update(&m,(unsigned char *)&(md_c[0]),sizeof(md_c));
+ MD_Update(&m,local_md,MD_DIGEST_LENGTH);
+ if (lock)
+ CRYPTO_w_lock(CRYPTO_LOCK_RAND);
+ MD_Update(&m,md,MD_DIGEST_LENGTH);
+ MD_Final(&m,md);
+ 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);
+ }
+ }
+
+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);
+ }
+
+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;
+ }
projects / cassiopeia.git / blobdiff