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-rw-r--r--random/gnupg-random.c810
1 files changed, 810 insertions, 0 deletions
diff --git a/random/gnupg-random.c b/random/gnupg-random.c
new file mode 100644
index 00000000..8f308621
--- /dev/null
+++ b/random/gnupg-random.c
@@ -0,0 +1,810 @@
+/* random.c - random number generator
+ * Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * GnuPG is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuPG is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ */
+
+
+/****************
+ * This random number generator is modelled after the one described
+ * in Peter Gutmann's Paper: "Software Generation of Practically
+ * Strong Random Numbers".
+ */
+
+#ifndef __HURD__
+#include <config.h>
+#else
+#include "gnupg-glue.h"
+#endif
+#include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <errno.h>
+#include <string.h>
+#include <time.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <fcntl.h>
+#ifdef HAVE_GETHRTIME
+ #include <sys/times.h>
+#endif
+#ifdef HAVE_GETTIMEOFDAY
+ #include <sys/times.h>
+#endif
+#ifdef HAVE_GETRUSAGE
+ #include <sys/resource.h>
+#endif
+#ifdef __MINGW32__
+ #include <process.h>
+#endif
+#ifndef __HURD__
+#include "util.h"
+#endif
+#ifndef __HURD__
+#include "rmd.h"
+#include "ttyio.h"
+#include "i18n.h"
+#include "random.h"
+#include "rand-internal.h"
+#include "dynload.h"
+#else
+#include "gnupg-rmd.h"
+#include "gnupg-random.h"
+#endif
+
+#ifndef RAND_MAX /* for SunOS */
+ #define RAND_MAX 32767
+#endif
+
+
+#if SIZEOF_UNSIGNED_LONG == 8
+ #define ADD_VALUE 0xa5a5a5a5a5a5a5a5
+#elif SIZEOF_UNSIGNED_LONG == 4
+ #define ADD_VALUE 0xa5a5a5a5
+#else
+ #error weird size for an unsigned long
+#endif
+
+#define BLOCKLEN 64 /* hash this amount of bytes */
+#define DIGESTLEN 20 /* into a digest of this length (rmd160) */
+/* poolblocks is the number of digests which make up the pool
+ * and poolsize must be a multiple of the digest length
+ * to make the AND operations faster, the size should also be
+ * a multiple of ulong
+ */
+#define POOLBLOCKS 30
+#define POOLSIZE (POOLBLOCKS*DIGESTLEN)
+#if (POOLSIZE % SIZEOF_UNSIGNED_LONG)
+ #error Please make sure that poolsize is a multiple of ulong
+#endif
+#define POOLWORDS (POOLSIZE / SIZEOF_UNSIGNED_LONG)
+
+
+static int is_initialized;
+#define MASK_LEVEL(a) do {if( a > 2 ) a = 2; else if( a < 0 ) a = 0; } while(0)
+static char *rndpool; /* allocated size is POOLSIZE+BLOCKLEN */
+static char *keypool; /* allocated size is POOLSIZE+BLOCKLEN */
+static size_t pool_readpos;
+static size_t pool_writepos;
+static int pool_filled;
+static int pool_balance;
+static int just_mixed;
+static int did_initial_extra_seeding;
+static char *seed_file_name;
+static int allow_seed_file_update;
+
+static int secure_alloc;
+static int quick_test;
+static int faked_rng;
+
+
+#ifndef __HURD__
+static void read_pool( byte *buffer, size_t length, int level );
+#else
+int read_pool( byte *buffer, size_t length, int level );
+#endif
+static void add_randomness( const void *buffer, size_t length, int source );
+static void random_poll(void);
+#ifndef __HURD__
+static void read_random_source( int requester, size_t length, int level);
+#else
+static int read_random_source( int requester, size_t length, int level);
+#endif
+static int gather_faked( void (*add)(const void*, size_t, int), int requester,
+ size_t length, int level );
+
+static struct {
+ ulong mixrnd;
+ ulong mixkey;
+ ulong slowpolls;
+ ulong fastpolls;
+ ulong getbytes1;
+ ulong ngetbytes1;
+ ulong getbytes2;
+ ulong ngetbytes2;
+ ulong addbytes;
+ ulong naddbytes;
+} rndstats;
+
+static void
+initialize(void)
+{
+ /* The data buffer is allocated somewhat larger, so that
+ * we can use this extra space (which is allocated in secure memory)
+ * as a temporary hash buffer */
+ rndpool = secure_alloc ? m_alloc_secure_clear(POOLSIZE+BLOCKLEN)
+ : m_alloc_clear(POOLSIZE+BLOCKLEN);
+ keypool = secure_alloc ? m_alloc_secure_clear(POOLSIZE+BLOCKLEN)
+ : m_alloc_clear(POOLSIZE+BLOCKLEN);
+ is_initialized = 1;
+#ifndef __HURD__
+ cipher_modules_constructor();
+#endif
+}
+
+static void
+burn_stack (int bytes)
+{
+ char buf[128];
+
+ memset (buf, 0, sizeof buf);
+ bytes -= sizeof buf;
+ if (bytes > 0)
+ burn_stack (bytes);
+}
+
+void
+random_dump_stats()
+{
+ fprintf(stderr,
+ "random usage: poolsize=%d mixed=%lu polls=%lu/%lu added=%lu/%lu\n"
+ " outmix=%lu getlvl1=%lu/%lu getlvl2=%lu/%lu\n",
+ POOLSIZE, rndstats.mixrnd, rndstats.slowpolls, rndstats.fastpolls,
+ rndstats.naddbytes, rndstats.addbytes,
+ rndstats.mixkey, rndstats.ngetbytes1, rndstats.getbytes1,
+ rndstats.ngetbytes2, rndstats.getbytes2 );
+}
+
+void
+secure_random_alloc()
+{
+ secure_alloc = 1;
+}
+
+
+int
+quick_random_gen( int onoff )
+{
+ int last;
+
+ read_random_source(0,0,0); /* init */
+ last = quick_test;
+ if( onoff != -1 )
+ quick_test = onoff;
+ return faked_rng? 1 : last;
+}
+
+
+/****************
+ * Fill the buffer with LENGTH bytes of cryptographically strong
+ * random bytes. level 0 is not very strong, 1 is strong enough
+ * for most usage, 2 is good for key generation stuff but may be very slow.
+ */
+void
+randomize_buffer( byte *buffer, size_t length, int level )
+{
+ char *p = get_random_bits( length*8, level, 1 );
+ memcpy( buffer, p, length );
+ m_free(p);
+}
+
+
+int
+random_is_faked()
+{
+ if( !is_initialized )
+ initialize();
+ return faked_rng || quick_test;
+}
+
+/****************
+ * Return a pointer to a randomized buffer of level 0 and LENGTH bits
+ * caller must free the buffer.
+ * Note: The returned value is rounded up to bytes.
+ */
+byte *
+get_random_bits( size_t nbits, int level, int secure )
+{
+ byte *buf, *p;
+ size_t nbytes = (nbits+7)/8;
+
+ if( quick_test && level > 1 )
+ level = 1;
+ MASK_LEVEL(level);
+ if( level == 1 ) {
+ rndstats.getbytes1 += nbytes;
+ rndstats.ngetbytes1++;
+ }
+ else if( level >= 2 ) {
+ rndstats.getbytes2 += nbytes;
+ rndstats.ngetbytes2++;
+ }
+
+ buf = secure && secure_alloc ? m_alloc_secure( nbytes ) : m_alloc( nbytes );
+ for( p = buf; nbytes > 0; ) {
+ size_t n = nbytes > POOLSIZE? POOLSIZE : nbytes;
+#ifdef __HURD__
+ n =
+#endif
+ read_pool( p, n, level );
+ nbytes -= n;
+ p += n;
+
+ }
+ return buf;
+}
+
+
+/****************
+ * Mix the pool
+ */
+static void
+mix_pool(byte *pool)
+{
+ char *hashbuf = pool + POOLSIZE;
+ char *p, *pend;
+ int i, n;
+ RMD160_CONTEXT md;
+
+ rmd160_init( &md );
+ #if DIGESTLEN != 20
+ #error must have a digest length of 20 for ripe-md-160
+ #endif
+ /* loop over the pool */
+ pend = pool + POOLSIZE;
+ memcpy(hashbuf, pend - DIGESTLEN, DIGESTLEN );
+ memcpy(hashbuf+DIGESTLEN, pool, BLOCKLEN-DIGESTLEN);
+ rmd160_mixblock( &md, hashbuf);
+ memcpy(pool, hashbuf, 20 );
+
+ p = pool;
+ for( n=1; n < POOLBLOCKS; n++ ) {
+ memcpy(hashbuf, p, DIGESTLEN );
+
+ p += DIGESTLEN;
+ if( p+DIGESTLEN+BLOCKLEN < pend )
+ memcpy(hashbuf+DIGESTLEN, p+DIGESTLEN, BLOCKLEN-DIGESTLEN);
+ else {
+ char *pp = p+DIGESTLEN;
+ for(i=DIGESTLEN; i < BLOCKLEN; i++ ) {
+ if( pp >= pend )
+ pp = pool;
+ hashbuf[i] = *pp++;
+ }
+ }
+
+ rmd160_mixblock( &md, hashbuf);
+ memcpy(p, hashbuf, 20 );
+ }
+ burn_stack (200); /* for the rmd160_mixblock() */
+}
+
+
+void
+set_random_seed_file( const char *name )
+{
+ if( seed_file_name )
+ BUG();
+ seed_file_name = m_strdup( name );
+}
+
+/****************
+ * Read in a seed form the random_seed file
+ * and return true if this was successful
+ */
+static int
+read_seed_file()
+{
+ int fd;
+ struct stat sb;
+ unsigned char buffer[POOLSIZE];
+ int n;
+
+ if( !seed_file_name )
+ return 0;
+
+ #ifdef HAVE_DOSISH_SYSTEM
+ fd = open( seed_file_name, O_RDONLY | O_BINARY );
+ #else
+ fd = open( seed_file_name, O_RDONLY );
+ #endif
+ if( fd == -1 && errno == ENOENT) {
+ allow_seed_file_update = 1;
+ return 0;
+ }
+
+ if( fd == -1 ) {
+ log_info(_("can't open `%s': %s\n"), seed_file_name, strerror(errno) );
+ return 0;
+ }
+ if( fstat( fd, &sb ) ) {
+ log_info(_("can't stat `%s': %s\n"), seed_file_name, strerror(errno) );
+ close(fd);
+ return 0;
+ }
+ if( !S_ISREG(sb.st_mode) ) {
+ log_info(_("`%s' is not a regular file - ignored\n"), seed_file_name );
+ close(fd);
+ return 0;
+ }
+ if( !sb.st_size ) {
+ log_info(_("note: random_seed file is empty\n") );
+ close(fd);
+ allow_seed_file_update = 1;
+ return 0;
+ }
+ if( sb.st_size != POOLSIZE ) {
+ log_info(_("warning: invalid size of random_seed file - not used\n") );
+ close(fd);
+ return 0;
+ }
+ do {
+ n = read( fd, buffer, POOLSIZE );
+ } while( n == -1 && errno == EINTR );
+ if( n != POOLSIZE ) {
+ log_fatal(_("can't read `%s': %s\n"), seed_file_name,strerror(errno) );
+ close(fd);
+ return 0;
+ }
+
+ close(fd);
+
+ add_randomness( buffer, POOLSIZE, 0 );
+ /* add some minor entropy to the pool now (this will also force a mixing) */
+ { pid_t x = getpid();
+ add_randomness( &x, sizeof(x), 0 );
+ }
+ { time_t x = time(NULL);
+ add_randomness( &x, sizeof(x), 0 );
+ }
+ { clock_t x = clock();
+ add_randomness( &x, sizeof(x), 0 );
+ }
+ /* And read a few bytes from our entropy source. By using
+ * a level of 0 this will not block and might not return anything
+ * with some entropy drivers, however the rndlinux driver will use
+ * /dev/urandom and return some stuff - Do not read to much as we
+ * want to be friendly to the scare system entropy resource. */
+ read_random_source( 0, 16, 0 );
+
+ allow_seed_file_update = 1;
+ return 1;
+}
+
+void
+update_random_seed_file()
+{
+ ulong *sp, *dp;
+ int fd, i;
+
+ if( !seed_file_name || !is_initialized || !pool_filled )
+ return;
+ if( !allow_seed_file_update ) {
+ log_info(_("note: random_seed file not updated\n"));
+ return;
+ }
+
+
+ /* copy the entropy pool to a scratch pool and mix both of them */
+ for(i=0,dp=(ulong*)keypool, sp=(ulong*)rndpool;
+ i < POOLWORDS; i++, dp++, sp++ ) {
+ *dp = *sp + ADD_VALUE;
+ }
+ mix_pool(rndpool); rndstats.mixrnd++;
+ mix_pool(keypool); rndstats.mixkey++;
+
+ #ifdef HAVE_DOSISH_SYSTEM
+ fd = open( seed_file_name, O_WRONLY|O_CREAT|O_TRUNC|O_BINARY,
+ S_IRUSR|S_IWUSR );
+ #else
+ fd = open( seed_file_name, O_WRONLY|O_CREAT|O_TRUNC, S_IRUSR|S_IWUSR );
+ #endif
+ if( fd == -1 ) {
+ log_info(_("can't create `%s': %s\n"), seed_file_name, strerror(errno) );
+ return;
+ }
+ do {
+ i = write( fd, keypool, POOLSIZE );
+ } while( i == -1 && errno == EINTR );
+ if( i != POOLSIZE ) {
+ log_info(_("can't write `%s': %s\n"), seed_file_name, strerror(errno) );
+ }
+ if( close(fd) )
+ log_info(_("can't close `%s': %s\n"), seed_file_name, strerror(errno) );
+}
+
+#ifdef __HURD__
+int readable_pool( size_t length, int level )
+{
+ size_t needed = 0;
+ size_t my_balance = pool_balance;
+ size_t available = (gatherwpos - gatherrpos + GATHERBUFSIZE) % GATHERBUFSIZE;
+
+ if (length > POOLSIZE)
+ length = POOLSIZE;
+
+ if (level < 2)
+ return length;
+
+ if( !pool_filled ) {
+ if( read_seed_file() )
+ pool_filled = 1;
+ }
+
+ if (!did_initial_extra_seeding)
+ {
+ /* Take account for initial extra seeding. */
+ needed = length;
+ if (needed < POOLSIZE/2)
+ needed = POOLSIZE/2;
+ my_balance = needed;
+
+ if (!pool_filled && pool_writepos + needed < POOLSIZE)
+ {
+ /* If the pool is not filled yet, we couldn't read the seed
+ file. Too bad. We will now have to take account for so many
+ random_poll()s as fit into the remaining pool. */
+
+ needed += (POOLSIZE - pool_writepos + needed + POOLSIZE/5 - 1) / (POOLSIZE/5);
+ }
+ }
+ else
+ {
+ if (!pool_filled)
+ needed += (POOLSIZE - pool_writepos + needed + POOLSIZE/5 - 1) / (POOLSIZE/5);
+ }
+
+ /* NEEDED contains the bytes needed for initialization, MY_BALANCE the resulting
+ available bytes. */
+ if (available < needed)
+ return 0;
+ return available + my_balance - needed;
+}
+#endif
+
+#ifndef __HURD__
+static void
+#else
+int
+#endif
+read_pool( byte *buffer, size_t length, int level )
+{
+ int i;
+ ulong *sp, *dp;
+
+ if( length > POOLSIZE ) {
+#ifndef __HURD__
+ log_fatal(_("too many random bits requested; the limit is %d\n"),
+ POOLSIZE*8-1 );
+#else
+ length = POOLSIZE;
+#endif
+ }
+
+ if( !pool_filled ) {
+ if( read_seed_file() )
+ pool_filled = 1;
+ }
+
+ /* For level 2 quality (key generation) we alwas make
+ * sure that the pool has been seeded enough initially */
+ if( level == 2 && !did_initial_extra_seeding ) {
+ size_t needed;
+
+ pool_balance = 0;
+ needed = length - pool_balance;
+ if( needed < POOLSIZE/2 )
+ needed = POOLSIZE/2;
+ else if( needed > POOLSIZE )
+ BUG();
+#ifdef __HURD__
+ needed =
+#endif
+ read_random_source( 3, needed, 2 );
+#ifdef __HURD__
+ if (! needed)
+ return 0;
+ /* XXX This will succeed with needed < POOLSIZE/2 even. But
+ erroring out will waste the random we already got. */
+#endif
+ pool_balance += needed;
+ did_initial_extra_seeding=1;
+ }
+
+ /* for level 2 make sure that there is enough random in the pool */
+ if( level == 2 && pool_balance < length ) {
+ size_t needed;
+
+ if( pool_balance < 0 )
+ pool_balance = 0;
+ needed = length - pool_balance;
+ if( needed > POOLSIZE )
+ BUG();
+#ifdef __HURD__
+ needed =
+#endif
+ read_random_source( 3, needed, 2 );
+ pool_balance += needed;
+ }
+
+#ifdef __HURD__
+ /* XXX This makes level 0 and 1 worse than needed at first start up. */
+ if (level == 2)
+#endif
+ /* make sure the pool is filled */
+ while( !pool_filled )
+ random_poll();
+
+ /* do always a fast random poll */
+ fast_random_poll();
+
+ if( !level ) { /* no need for cryptographic strong random */
+ /* create a new pool */
+ for(i=0,dp=(ulong*)keypool, sp=(ulong*)rndpool;
+ i < POOLWORDS; i++, dp++, sp++ )
+ *dp = *sp + ADD_VALUE;
+ /* must mix both pools */
+ mix_pool(rndpool); rndstats.mixrnd++;
+ mix_pool(keypool); rndstats.mixkey++;
+ memcpy( buffer, keypool, length );
+ return length;
+ }
+ else {
+#ifdef __HURD__
+ int amount;
+#endif
+ /* mix the pool (if add_randomness() didn't it) */
+ if( !just_mixed ) {
+ mix_pool(rndpool);
+ rndstats.mixrnd++;
+ }
+ /* create a new pool */
+ for(i=0,dp=(ulong*)keypool, sp=(ulong*)rndpool;
+ i < POOLWORDS; i++, dp++, sp++ )
+ *dp = *sp + ADD_VALUE;
+ /* and mix both pools */
+ mix_pool(rndpool); rndstats.mixrnd++;
+ mix_pool(keypool); rndstats.mixkey++;
+ /* read the required data
+ * we use a readpoiter to read from a different postion each
+ * time */
+#ifdef __HURD__
+ if (level == 2 && length > pool_balance)
+ length = pool_balance;
+ amount = length;
+#endif
+ while( length-- ) {
+ *buffer++ = keypool[pool_readpos++];
+ if( pool_readpos >= POOLSIZE )
+ pool_readpos = 0;
+ pool_balance--;
+ }
+ if( pool_balance < 0 )
+ pool_balance = 0;
+ /* and clear the keypool */
+ memset( keypool, 0, POOLSIZE );
+#ifdef __HURD__
+ return amount;
+#endif
+ }
+}
+
+
+/****************
+ * Add LENGTH bytes of randomness from buffer to the pool.
+ * source may be used to specify the randomness source.
+ * Source is:
+ * 0 - used ony for initialization
+ * 1 - fast random poll function
+ * 2 - normal poll function
+ * 3 - used when level 2 random quality has been requested
+ * to do an extra pool seed.
+ */
+static void
+add_randomness( const void *buffer, size_t length, int source )
+{
+ const byte *p = buffer;
+
+ if( !is_initialized )
+ initialize();
+ rndstats.addbytes += length;
+ rndstats.naddbytes++;
+ while( length-- ) {
+ rndpool[pool_writepos++] = *p++;
+ if( pool_writepos >= POOLSIZE ) {
+ if( source > 1 )
+ pool_filled = 1;
+ pool_writepos = 0;
+ mix_pool(rndpool); rndstats.mixrnd++;
+ just_mixed = !length;
+ }
+ }
+}
+
+
+
+static void
+random_poll()
+{
+ rndstats.slowpolls++;
+ read_random_source( 2, POOLSIZE/5, 1 );
+}
+
+
+void
+fast_random_poll()
+{
+ static void (*fnc)( void (*)(const void*, size_t, int), int) = NULL;
+ static int initialized = 0;
+
+ rndstats.fastpolls++;
+ if( !initialized ) {
+ if( !is_initialized )
+ initialize();
+ initialized = 1;
+ fnc = dynload_getfnc_fast_random_poll();
+ }
+ if( fnc ) {
+ (*fnc)( add_randomness, 1 );
+ return;
+ }
+
+ /* fall back to the generic function */
+ #if HAVE_GETHRTIME
+ { hrtime_t tv;
+ tv = gethrtime();
+ add_randomness( &tv, sizeof(tv), 1 );
+ }
+ #elif HAVE_GETTIMEOFDAY
+ { struct timeval tv;
+ if( gettimeofday( &tv, NULL ) )
+ BUG();
+ add_randomness( &tv.tv_sec, sizeof(tv.tv_sec), 1 );
+ add_randomness( &tv.tv_usec, sizeof(tv.tv_usec), 1 );
+ }
+ #elif HAVE_CLOCK_GETTIME
+ { struct timespec tv;
+ if( clock_gettime( CLOCK_REALTIME, &tv ) == -1 )
+ BUG();
+ add_randomness( &tv.tv_sec, sizeof(tv.tv_sec), 1 );
+ add_randomness( &tv.tv_nsec, sizeof(tv.tv_nsec), 1 );
+ }
+ #else /* use times */
+ #ifndef HAVE_DOSISH_SYSTEM
+ { struct tms buf;
+ times( &buf );
+ add_randomness( &buf, sizeof buf, 1 );
+ }
+ #endif
+ #endif
+ #ifdef HAVE_GETRUSAGE
+ #ifndef RUSAGE_SELF
+ #ifdef __GCC__
+ #warning There is no RUSAGE_SELF on this system
+ #endif
+ #else
+ { struct rusage buf;
+ /* QNX/Neutrino does return ENOSYS - so we just ignore it and
+ * add whatever is in buf. In a chroot environment it might not
+ * work at all (i.e. because /proc/ is not accessible), so we better
+ * ognore all error codes and hope for the best
+ */
+ getrusage( RUSAGE_SELF, &buf );
+
+ add_randomness( &buf, sizeof buf, 1 );
+ memset( &buf, 0, sizeof buf );
+ }
+ #endif
+ #endif
+ /* time and clock are availabe on all systems - so
+ * we better do it just in case one of the above functions
+ * didn't work */
+ { time_t x = time(NULL);
+ add_randomness( &x, sizeof(x), 1 );
+ }
+ { clock_t x = clock();
+ add_randomness( &x, sizeof(x), 1 );
+ }
+}
+
+
+#ifndef __HURD__
+static void
+#else
+static int
+#endif
+read_random_source( int requester, size_t length, int level )
+{
+ static int (*fnc)(void (*)(const void*, size_t, int), int,
+ size_t, int) = NULL;
+#ifdef __HURD__
+ int got;
+#endif
+ if( !fnc ) {
+ if( !is_initialized )
+ initialize();
+ fnc = dynload_getfnc_gather_random();
+ if( !fnc ) {
+ faked_rng = 1;
+ fnc = gather_faked;
+ }
+ if( !requester && !length && !level )
+#ifndef __HURD__
+ return; /* init only */
+#else
+ return 0;
+#endif
+ }
+#ifndef __HURD__
+ if( (*fnc)( add_randomness, requester, length, level ) < 0 )
+ log_fatal("No way to gather entropy for the RNG\n");
+#else
+ got = (*fnc)( add_randomness, requester, length, level );
+ if (got < 0)
+ log_fatal("No way to gather entropy for the RNG\n");
+ return got;
+#endif
+}
+
+
+static int
+gather_faked( void (*add)(const void*, size_t, int), int requester,
+ size_t length, int level )
+{
+ static int initialized=0;
+ size_t n;
+ char *buffer, *p;
+
+ if( !initialized ) {
+ log_info(_("WARNING: using insecure random number generator!!\n"));
+ tty_printf(_("The random number generator is only a kludge to let\n"
+ "it run - it is in no way a strong RNG!\n\n"
+ "DON'T USE ANY DATA GENERATED BY THIS PROGRAM!!\n\n"));
+ initialized=1;
+ #ifdef HAVE_RAND
+ srand(make_timestamp()*getpid());
+ #else
+ srandom(make_timestamp()*getpid());
+ #endif
+ }
+ printf("WAITING FOR %i bytes.\n", length);
+ p = buffer = m_alloc( length );
+ n = length;
+ #ifdef HAVE_RAND
+ while( n-- )
+ *p++ = ((unsigned)(1 + (int) (256.0*rand()/(RAND_MAX+1.0)))-1);
+ #else
+ while( n-- )
+ *p++ = ((unsigned)(1 + (int) (256.0*random()/(RAND_MAX+1.0)))-1);
+ #endif
+ add_randomness( buffer, length, requester );
+ m_free(buffer);
+ return 0; /* okay */
+}
+