diff options
Diffstat (limited to 'cipher/rndegd.c')
| -rw-r--r-- | cipher/rndegd.c | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/cipher/rndegd.c b/cipher/rndegd.c new file mode 100644 index 000000000..ef9f6e04b --- /dev/null +++ b/cipher/rndegd.c @@ -0,0 +1,205 @@ +/* rndegd.c - interface to the EGD + * Copyright (C) 1999 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> +#include <string.h> +#include <unistd.h> +#include <sys/socket.h> +#include "types.h" +#include "util.h" +#include "ttyio.h" +#include "dynload.h" + +#ifdef IS_MODULE + #define _(a) (a) +#else + #include "i18n.h" +#endif + +static int gather_random( void (*add)(const void*, size_t, int), int requester, + size_t length, int level ); + +#ifdef IS_MODULE +static void tty_printf(const char *fmt, ... ) +{ + g10_log_info("tty_printf not available (%s)\n", fmt ); +} +#endif + + +static int +do_write( int fd, void *buf, size_t nbytes ) +{ + size_t nleft = nbytes; + ssize_t nwritten; + + while( nleft > 0 ) { + nwritten = write( fd, buf, nleft); + if( nwritten < 0 ) { + if( errno = EINTR ) + continue; + return -1; + } + nleft -= nwritten; + buf = (char*)buf + nwritten; + } + return 0; +} + + my $bytes = shift; + $msg = pack("CC", 0x01, $bytes); + $s->syswrite($msg, length($msg)); + my $nread = $s->sysread($buf, 1); + die unless $nread == 1; + my $count = unpack("C",$buf); + $nread = $s->sysread($buf, $count); + die "didn't get all the entropy" unless $nread == $count; + print "got $count bytes of entropy: ",unpack("H*",$buf),"\n"; + + + + +static int +gather_random( void (*add)(const void*, size_t, int), int requester, + size_t length, int level ) +{ + static int fd = -1; + int n; + int warn=0; + byte buffer[768]; + + if( fd == -1 ) { + const char *name = "/tmp/entropy"; + struct sockaddr_un addr; + int addr_len; + + memset( &addr, 0, sizeof addr ); + addr.sun_family = AF_UNIX; + strcpy( addr.sun_path, name ); /* fixme: check that it is long enough */ + addr_len = strlen(addr.sun_path) + sizeof addr.sun_family; + + fd = socket(AF_UNIX, SOCK_STREAM, 0); + if( fd == -1 ) + g10_log_fatal("can't create unix domain socket: %s\n", + strerror(errno) ); + if( connect( fd, (struct sockaddr*)&addr, addr_len) == -1 ) + g10_log_fatal("can't connect to `%s': %s\n", + name, strerror(errno) ); + } + + if( do_write( fd, "\x01", 1 ) == -1 ) + g10_log_fatal("can't write to the EGD: %s\n", strerror(errno) ); + + while( length ) { + 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 = 0; /* set to 1 to print onyl one warning */ + continue; + } + else if( rc == -1 ) { + tty_printf("select() error: %s\n", strerror(errno)); + continue; + } + + do { + int nbytes = length < sizeof(buffer)? length : sizeof(buffer); + n = read(fd, buffer, nbytes ); + if( n >= 0 && n > nbytes ) { + g10_log_error("bogus read from random device (n=%d)\n", n ); + n = nbytes; + } + } while( n == -1 && errno == EINTR ); + if( n == -1 ) + g10_log_fatal("read error on EGD: %s\n", strerror(errno)); + (*add)( buffer, n, requester ); + length -= n; + } + memset(buffer, 0, sizeof(buffer) ); + + return 0; /* success */ +} + + + +#ifndef IS_MODULE +static +#endif +const char * const gnupgext_version = "RNDEGD ($Revision$)"; + +static struct { + int class; + int version; + void *func; +} func_table[] = { + { 40, 1, gather_random }, +}; + + +#ifndef IS_MODULE +static +#endif +void * +gnupgext_enum_func( int what, int *sequence, int *class, int *vers ) +{ + void *ret; + int i = *sequence; + + do { + if ( i >= DIM(func_table) || i < 0 ) { + return NULL; + } + *class = func_table[i].class; + *vers = func_table[i].version; + ret = func_table[i].func; + i++; + } while ( what && what != *class ); + + *sequence = i; + return ret; +} + +#ifndef IS_MODULE +void +rndegd_constructor(void) +{ + register_internal_cipher_extension( gnupgext_version, + gnupgext_enum_func ); +} +#endif + |