diff options
Diffstat (limited to 'crypto/openssl/crypto/rand/md_rand.c')
-rw-r--r-- | crypto/openssl/crypto/rand/md_rand.c | 433 |
1 files changed, 358 insertions, 75 deletions
diff --git a/crypto/openssl/crypto/rand/md_rand.c b/crypto/openssl/crypto/rand/md_rand.c index 6bd1960..da4258c 100644 --- a/crypto/openssl/crypto/rand/md_rand.c +++ b/crypto/openssl/crypto/rand/md_rand.c @@ -55,15 +55,77 @@ * copied and put under another distribution licence * [including the GNU Public Licence.] */ +/* ==================================================================== + * Copyright (c) 1998-2000 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 ENTROPY_NEEDED 16 /* require 128 bits = 16 bytes of randomness */ + +#ifndef MD_RAND_DEBUG +# ifndef NDEBUG +# define NDEBUG +# endif +#endif +#include <assert.h> #include <stdio.h> -#include <sys/types.h> #include <time.h> #include <string.h> #include "openssl/e_os.h" #include <openssl/crypto.h> +#include <openssl/err.h> #if !defined(USE_MD5_RAND) && !defined(USE_SHA1_RAND) && !defined(USE_MDC2_RAND) && !defined(USE_MD2_RAND) #if !defined(NO_SHA) && !defined(NO_SHA1) @@ -121,6 +183,10 @@ #include <openssl/rand.h> +#ifdef BN_DEBUG +# define PREDICT +#endif + /* #define NORAND 1 */ /* #define PREDICT 1 */ @@ -129,17 +195,29 @@ 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; + +#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_bytes(unsigned char *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_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(void) @@ -155,22 +233,49 @@ static void ssleay_rand_cleanup(void) memset(md,0,MD_DIGEST_LENGTH); md_count[0]=0; md_count[1]=0; + entropy=0; } -static void ssleay_rand_seed(const void *buf, int num) +static void ssleay_rand_add(const void *buf, int num, double add) { - int i,j,k,st_idx,st_num; + int i,j,k,st_idx; + long md_c[2]; + unsigned char local_md[MD_DIGEST_LENGTH]; MD_CTX m; #ifdef NORAND return; #endif + /* + * (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. + */ + CRYPTO_w_lock(CRYPTO_LOCK_RAND); st_idx=state_index; - st_num=state_num; - state_index=(state_index+num); + /* 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; @@ -181,6 +286,14 @@ static void ssleay_rand_seed(const void *buf, int num) 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); + CRYPTO_w_unlock(CRYPTO_LOCK_RAND); for (i=0; i<num; i+=MD_DIGEST_LENGTH) @@ -189,7 +302,7 @@ static void ssleay_rand_seed(const void *buf, int num) j=(j > MD_DIGEST_LENGTH)?MD_DIGEST_LENGTH:j; MD_Init(&m); - MD_Update(&m,md,MD_DIGEST_LENGTH); + MD_Update(&m,local_md,MD_DIGEST_LENGTH); k=(st_idx+j)-STATE_SIZE; if (k > 0) { @@ -200,97 +313,177 @@ static void ssleay_rand_seed(const void *buf, int num) MD_Update(&m,&(state[st_idx]),j); MD_Update(&m,buf,j); - MD_Update(&m,(unsigned char *)&(md_count[0]),sizeof(md_count)); - MD_Final(md,&m); - md_count[1]++; + 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<j; k++) { - state[st_idx++]^=md[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; - st_num=STATE_SIZE; - } } } memset((char *)&m,0,sizeof(m)); + + 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; + CRYPTO_w_unlock(CRYPTO_LOCK_RAND); + +#ifndef THREADS + assert(md_c[1] == md_count[1]); +#endif } -static void ssleay_rand_bytes(unsigned char *buf, int num) +static void ssleay_rand_seed(const void *buf, int num) + { + ssleay_rand_add(buf, num, num); + } + +static void ssleay_rand_initialize(void) { - int i,j,k,st_num,st_idx; - MD_CTX m; - static int init=1; unsigned long l; +#ifndef GETPID_IS_MEANINGLESS + pid_t curr_pid = getpid(); +#endif #ifdef DEVRANDOM FILE *fh; #endif -#ifdef PREDICT - { - static unsigned char val=0; - - for (i=0; i<num; i++) - buf[i]=val++; +#ifdef NORAND return; - } #endif - CRYPTO_w_lock(CRYPTO_LOCK_RAND); + CRYPTO_w_unlock(CRYPTO_LOCK_RAND); + /* put in some default random data, we need more than just this */ +#ifndef GETPID_IS_MEANINGLESS + l=curr_pid; + RAND_add(&l,sizeof(l),0); + l=getuid(); + RAND_add(&l,sizeof(l),0); +#endif + l=time(NULL); + RAND_add(&l,sizeof(l),0); - if (init) +#ifdef DEVRANDOM + /* Use a random entropy pool device. Linux, FreeBSD and OpenBSD + * have this. Use /dev/urandom if you can as /dev/random may block + * if it runs out of random entries. */ + + if ((fh = fopen(DEVRANDOM, "r")) != NULL) { - CRYPTO_w_unlock(CRYPTO_LOCK_RAND); - /* put in some default random data, we need more than - * just this */ - RAND_seed(&m,sizeof(m)); -#ifndef MSDOS - l=getpid(); - RAND_seed(&l,sizeof(l)); - l=getuid(); - RAND_seed(&l,sizeof(l)); + unsigned char tmpbuf[ENTROPY_NEEDED]; + int n; + + setvbuf(fh, NULL, _IONBF, 0); + n=fread((unsigned char *)tmpbuf,1,ENTROPY_NEEDED,fh); + fclose(fh); + RAND_add(tmpbuf,sizeof tmpbuf,n); + memset(tmpbuf,0,n); + } #endif - l=time(NULL); - RAND_seed(&l,sizeof(l)); - -/* #ifdef DEVRANDOM */ - /* - * Use a random entropy pool device. - * Linux 1.3.x and FreeBSD-Current has - * this. Use /dev/urandom if you can - * as /dev/random will block if it runs out - * of random entries. - */ - if ((fh = fopen(DEVRANDOM, "r")) != NULL) - { - unsigned char tmpbuf[32]; - - fread((unsigned char *)tmpbuf,1,32,fh); - /* we don't care how many bytes we read, - * we will just copy the 'stack' if there is - * nothing else :-) */ - fclose(fh); - RAND_seed(tmpbuf,32); - memset(tmpbuf,0,32); - } -/* #endif */ #ifdef PURIFY - memset(state,0,STATE_SIZE); - memset(md,0,MD_DIGEST_LENGTH); + memset(state,0,STATE_SIZE); + memset(md,0,MD_DIGEST_LENGTH); +#endif + CRYPTO_w_lock(CRYPTO_LOCK_RAND); + initialized=1; + } + +static int ssleay_rand_bytes(unsigned char *buf, int num) + { + int i,j,k,st_num,st_idx; + int ok; + long md_c[2]; + unsigned char local_md[MD_DIGEST_LENGTH]; + MD_CTX m; +#ifndef GETPID_IS_MEANINGLESS + pid_t curr_pid = getpid(); #endif - CRYPTO_w_lock(CRYPTO_LOCK_RAND); - init=0; + +#ifdef PREDICT + if (rand_predictable) + { + static unsigned char val=0; + + for (i=0; i<num; i++) + buf[i]=val++; + return(1); + } +#endif + + /* + * (Based on the rand(3) manpage:) + * + * For each group of 10 bytes (or less), we do the following: + * + * Input into the hash function the top 10 bytes from 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 (up to) 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'. + */ + + CRYPTO_w_lock(CRYPTO_LOCK_RAND); + + if (!initialized) + ssleay_rand_initialize(); + + 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. + */ + entropy -= num; + if (entropy < 0) + entropy = 0; } 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_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; CRYPTO_w_unlock(CRYPTO_LOCK_RAND); while (num > 0) @@ -298,8 +491,15 @@ static void ssleay_rand_bytes(unsigned char *buf, int num) j=(num >= MD_DIGEST_LENGTH/2)?MD_DIGEST_LENGTH/2:num; num-=j; MD_Init(&m); - MD_Update(&m,&(md[MD_DIGEST_LENGTH/2]),MD_DIGEST_LENGTH/2); - MD_Update(&m,(unsigned char *)&(md_count[0]),sizeof(md_count)); +#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/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 */ #endif @@ -311,29 +511,112 @@ static void ssleay_rand_bytes(unsigned char *buf, int num) } else MD_Update(&m,&(state[st_idx]),j); - MD_Final(md,&m); + MD_Final(local_md,&m); for (i=0; i<j; i++) { + state[st_idx++]^=local_md[i]; /* may compete with other threads */ + *(buf++)=local_md[i+MD_DIGEST_LENGTH/2]; if (st_idx >= st_num) st_idx=0; - state[st_idx++]^=md[i]; - *(buf++)=md[i+MD_DIGEST_LENGTH/2]; } } MD_Init(&m); - MD_Update(&m,(unsigned char *)&(md_count[0]),sizeof(md_count)); - md_count[0]++; + 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); + 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; + + CRYPTO_w_lock(CRYPTO_LOCK_RAND); + + if (!initialized) + ssleay_rand_initialize(); + ret = entropy >= ENTROPY_NEEDED; + + CRYPTO_w_unlock(CRYPTO_LOCK_RAND); + + return ret; } #ifdef WINDOWS #include <windows.h> #include <openssl/rand.h> +int RAND_event(UINT iMsg, WPARAM wParam, LPARAM lParam) + { + double add_entropy=0; + SYSTEMTIME t; + + switch (iMsg) + { + case WM_KEYDOWN: + { + static WPARAM key; + if (key != wParam) + add_entropy = 0.05; + key = wParam; + } + break; + case WM_MOUSEMOVE: + { + static int lastx,lasty,lastdx,lastdy; + int x,y,dx,dy; + + x=LOWORD(lParam); + y=HIWORD(lParam); + dx=lastx-x; + dy=lasty-y; + if (dx != 0 && dy != 0 && dx-lastdx != 0 && dy-lastdy != 0) + add_entropy=.2; + lastx=x, lasty=y; + lastdx=dx, lastdy=dy; + } + break; + } + + GetSystemTime(&t); + RAND_add(&iMsg, sizeof(iMsg), add_entropy); + RAND_add(&wParam, sizeof(wParam), 0); + RAND_add(&lParam, sizeof(lParam), 0); + RAND_add(&t, sizeof(t), 0); + + return (RAND_status()); + } + /***************************************************************************** * Initialisation function for the SSL random generator. Takes the contents * of the screen as random seed. @@ -354,12 +637,12 @@ static void ssleay_rand_bytes(unsigned char *buf, int num) */ /* * I have modified the loading of bytes via RAND_seed() mechanism since - * the origional would have been very very CPU intensive since RAND_seed() + * the original would have been very very CPU intensive since RAND_seed() * does an MD5 per 16 bytes of input. The cost to digest 16 bytes is the same * as that to digest 56 bytes. So under the old system, a screen of - * 1024*768*256 would have been CPU cost of approximatly 49,000 56 byte MD5 + * 1024*768*256 would have been CPU cost of approximately 49,000 56 byte MD5 * digests or digesting 2.7 mbytes. What I have put in place would - * be 48 16k MD5 digests, or efectivly 48*16+48 MD5 bytes or 816 kbytes + * be 48 16k MD5 digests, or effectively 48*16+48 MD5 bytes or 816 kbytes * or about 3.5 times as much. * - eric */ |