diff options
Diffstat (limited to 'cipher/rand-unix.c')
| -rw-r--r-- | cipher/rand-unix.c | 203 |
1 files changed, 203 insertions, 0 deletions
diff --git a/cipher/rand-unix.c b/cipher/rand-unix.c new file mode 100644 index 000000000..a0f19d824 --- /dev/null +++ b/cipher/rand-unix.c @@ -0,0 +1,203 @@ +/* rand-unix.c - raw random number generator for unix like OSes + * Copyright (C) 1998 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 + */ + + +#include <config.h> +#include <stdio.h> +#include <stdlib.h> +#include <assert.h> +#include <errno.h> +#include <sys/time.h> +#include <sys/types.h> +#include <sys/stat.h> +#ifdef HAVE_GETHRTIME + #include <sys/times.h> +#endif +#ifndef HAVE_GETTIMEOFTIME + #include <sys/times.h> +#endif +#ifdef HAVE_GETRUSAGE + #include <sys/resource.h> +#endif +#include <string.h> +#include <unistd.h> +#include <fcntl.h> +#include "util.h" +#include "rmd.h" +#include "ttyio.h" +#include "i18n.h" +#include "rand-internal.h" +#ifdef USE_RAND_UNIX /* This file is only for real systems */ + + +void +random_poll() +{ + char buf[POOLSIZE/5]; + read_random_source( buf, POOLSIZE/5, 1 ); /* read /dev/urandom */ + add_randomness( buf, POOLSIZE/5, 2); + memset( buf, 0, POOLSIZE/5); +} + + +void +fast_random_poll() +{ + #if HAVE_GETHRTIME + { hrtime_t tv; + tv = gethrtime(void); + add_randomness( &tv, sizeof(tv), 1 ); + } + #elif HAVE_GETTIMEOFTIME + { 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 ); + } + #else /* use times */ + { struct tms buf; + times( &buf ); + add_randomness( &buf, sizeof buf, 1 ); + } + #endif + #ifdef HAVE_GETRUSAGE + { struct rusage buf; + if( getrusage( RUSAGE_SELF, &buf ) ) + BUG(); + add_randomness( &buf, sizeof buf, 1 ); + memset( &buf, 0, sizeof buf ); + } + #endif +} + + +#ifdef HAVE_DEV_RANDOM /* we have the /dev/random device */ + +/**************** + * Used to open the Linux /dev/random device + */ +static int +open_device( const char *name, int minor ) +{ + int fd; + struct stat sb; + + fd = open( name, O_RDONLY ); + if( fd == -1 ) + log_fatal("can't open %s: %s\n", name, strerror(errno) ); + if( fstat( fd, &sb ) ) + log_fatal("stat() off %s failed: %s\n", name, strerror(errno) ); + #if defined(__sparc__) && defined(__linux__) + #warning something is wrong with UltraPenguin /dev/random + #else + if( !S_ISCHR(sb.st_mode) ) + log_fatal("invalid random device!\n" ); + #endif + return fd; +} + + +void +read_random_source( byte *buffer, size_t length, int level ) +{ + static int fd_urandom = -1; + static int fd_random = -1; + int fd; + int n; + int warn=0; + + if( level == 2 ) { + if( fd_random == -1 ) + fd_random = open_device( "/dev/random", 8 ); + fd = fd_random; + } + else { + /* fixme: we should use a simpler one for level 0, + * because reading from /dev/urandom removes entropy + * and the next read on /dev/random may have to wait */ + if( fd_urandom == -1 ) + fd_urandom = open_device( "/dev/urandom", 9 ); + fd = fd_urandom; + } + + + do { + fd_set rfds; + struct timeval tv; + int rc; + + FD_ZERO(&rfds); + FD_SET(fd, &rfds); + tv.tv_sec = 3; + tv.tv_usec = 0; + if( !(rc=select(fd+1, &rfds, NULL, NULL, &tv)) ) { + if( !warn ) + tty_printf( _( +"\n" +"Not enough random bytes available. Please do some other work to give\n" +"the OS a chance to collect more entropy! (Need %d more bytes)\n"), length ); + warn = 1; + continue; + } + else if( rc == -1 ) { + tty_printf("select() error: %s\n", strerror(errno)); + continue; + } + + assert( length < 500 ); + do { + n = read(fd, buffer, length ); + if( n >= 0 && n > length ) { + log_error("bogus read from random device (n=%d)\n", n ); + n = length; + } + } while( n == -1 && errno == EINTR ); + if( n == -1 ) + log_fatal("read error on random device: %s\n", strerror(errno) ); + assert( n <= length ); + buffer += n; + length -= n; + } while( length ); +} + +#else /* not HAVE_DEV_RANDOM */ + + +/**************** + * The real random data collector for Unix. + * this function runs in a loop, waiting for commands from ctrl_fd + * and normally starts a collection process, which outputs random + * bytes to out_fd. + * + * Commands understand from ctrl_fd are single character: + * 'Q' = Quit the loop + * 'S' = Start a new collection process + */ +static void +collector( FILE *ctrlfp, FILE *outfp ) +{ + + + +} + +#endif /* no HAVE_DEV_RANDOM */ +#endif /* USE_RAND_UNIX */ |