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- (djm) Ignore fix & patchlevel in OpenSSL version check. Patch from
solar@openwall.com - (djm) Rework entropy code. If the OpenSSL PRNG is has not been internally seeded, execute a subprogram "ssh-rand-helper" to obtain some entropy for us. Rewrite the old in-process entropy collecter as an example ssh-rand-helper. - (djm) Always perform ssh_prng_cmds path lookups in configure, even if we don't end up using ssh_prng_cmds (so we always get a valid file)
This commit is contained in:
Damien Miller
parent
278f907a2d
commit
62116dcc0a
12
ChangeLog
12
ChangeLog
@ -1,3 +1,13 @@
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20011222
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- (djm) Ignore fix & patchlevel in OpenSSL version check. Patch from
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solar@openwall.com
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- (djm) Rework entropy code. If the OpenSSL PRNG is has not been
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internally seeded, execute a subprogram "ssh-rand-helper" to obtain
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some entropy for us. Rewrite the old in-process entropy collecter as
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an example ssh-rand-helper.
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- (djm) Always perform ssh_prng_cmds path lookups in configure, even if
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we don't end up using ssh_prng_cmds (so we always get a valid file)
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20011221
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- (djm) Add option to gnome-ssh-askpass to stop it from grabbing the X
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server. I have found this necessary to avoid server hangs with X input
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@ -7086,4 +7096,4 @@
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- Wrote replacements for strlcpy and mkdtemp
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- Released 1.0pre1
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$Id: ChangeLog,v 1.1705 2001/12/21 04:00:19 djm Exp $
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$Id: ChangeLog,v 1.1706 2001/12/23 14:41:47 djm Exp $
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11
Makefile.in
11
Makefile.in
@ -1,4 +1,4 @@
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# $Id: Makefile.in,v 1.190 2001/11/11 23:34:23 djm Exp $
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# $Id: Makefile.in,v 1.191 2001/12/23 14:41:48 djm Exp $
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prefix=@prefix@
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exec_prefix=@exec_prefix@
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@ -23,7 +23,8 @@ PATHS= -DETCDIR=\"$(sysconfdir)\" \
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-D_PATH_SSH_PROGRAM=\"$(SSH_PROGRAM)\" \
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-D_PATH_SSH_ASKPASS_DEFAULT=\"$(ASKPASS_PROGRAM)\" \
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-D_PATH_SFTP_SERVER=\"$(SFTP_SERVER)\" \
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-D_PATH_SSH_PIDDIR=\"$(piddir)\"
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-D_PATH_SSH_PIDDIR=\"$(piddir)\" \
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-DSSH_RAND_HELPER=\"$(libexecdir)/ssh-rand-helper\"
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CC=@CC@
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LD=@LD@
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@ -44,7 +45,7 @@ INSTALL_SSH_PRNG_CMDS=@INSTALL_SSH_PRNG_CMDS@
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@NO_SFTP@SFTP_PROGS=sftp-server$(EXEEXT) sftp$(EXEEXT)
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TARGETS=ssh$(EXEEXT) sshd$(EXEEXT) ssh-add$(EXEEXT) ssh-keygen$(EXEEXT) ssh-keyscan${EXEEXT} ssh-agent$(EXEEXT) scp$(EXEEXT) $(SFTP_PROGS)
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TARGETS=ssh$(EXEEXT) sshd$(EXEEXT) ssh-add$(EXEEXT) ssh-keygen$(EXEEXT) ssh-keyscan${EXEEXT} ssh-agent$(EXEEXT) scp$(EXEEXT) ssh-rand-helper${EXEEXT} $(SFTP_PROGS)
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LIBSSH_OBJS=atomicio.o authfd.o authfile.o bufaux.o buffer.o canohost.o channels.o cipher.o compat.o compress.o crc32.o deattack.o dh.o dispatch.o mac.o hostfile.o key.o kex.o kexdh.o kexgex.o log.o match.o misc.o mpaux.o nchan.o packet.o radix.o rijndael.o entropy.o readpass.o rsa.o scard.o ssh-dss.o ssh-rsa.o tildexpand.o ttymodes.o uidswap.o uuencode.o xmalloc.o
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@ -121,6 +122,9 @@ sftp-server$(EXEEXT): $(LIBCOMPAT) libssh.a sftp.o sftp-common.o sftp-server.o
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sftp$(EXEEXT): $(LIBCOMPAT) libssh.a sftp.o sftp-client.o sftp-int.o sftp-common.o sftp-glob.o
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$(LD) -o $@ sftp.o sftp-client.o sftp-common.o sftp-int.o sftp-glob.o $(LDFLAGS) -lssh -lopenbsd-compat $(LIBS)
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ssh-rand-helper${EXEEXT}: $(LIBCOMPAT) ssh-rand-helper.o
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$(LD) -o $@ ssh-rand-helper.o atomicio.o log.o xmalloc.o $(LDFLAGS) -lopenbsd-compat $(LIBS)
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# test driver for the loginrec code - not built by default
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logintest: logintest.o $(LIBCOMPAT) libssh.a loginrec.o
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$(LD) -o $@ logintest.o $(LDFLAGS) loginrec.o -lopenbsd-compat -lssh $(LIBS)
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@ -197,6 +201,7 @@ install-files: scard-install
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$(INSTALL) -m 0755 -s ssh-keygen $(DESTDIR)$(bindir)/ssh-keygen
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$(INSTALL) -m 0755 -s ssh-keyscan $(DESTDIR)$(bindir)/ssh-keyscan
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$(INSTALL) -m 0755 -s sshd $(DESTDIR)$(sbindir)/sshd
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$(INSTALL) -m 0755 -s ssh-rand-helper $(DESTDIR)$(libexecdir)/ssh-rand-helper
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@NO_SFTP@$(INSTALL) -m 0755 -s sftp $(DESTDIR)$(bindir)/sftp
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@NO_SFTP@$(INSTALL) -m 0755 -s sftp-server $(DESTDIR)$(SFTP_SERVER)
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$(INSTALL) -m 644 ssh.1.out $(DESTDIR)$(mandir)/$(mansubdir)1/ssh.1
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38
configure.ac
38
configure.ac
@ -1,4 +1,4 @@
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# $Id: configure.ac,v 1.6 2001/12/07 17:20:48 mouring Exp $
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i# $Id: configure.ac,v 1.7 2001/12/23 14:41:48 djm Exp $
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AC_INIT
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AC_CONFIG_SRCDIR([ssh.c])
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@ -1598,28 +1598,28 @@ AC_ARG_WITH(prngd-socket,
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INSTALL_SSH_PRNG_CMDS=""
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rm -f prng_commands
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if (test -z "$RANDOM_POOL" && test -z "$PRNGD") ; then
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# Use these commands to collect entropy
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OSSH_PATH_ENTROPY_PROG(PROG_LS, ls)
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OSSH_PATH_ENTROPY_PROG(PROG_NETSTAT, netstat)
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OSSH_PATH_ENTROPY_PROG(PROG_ARP, arp)
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OSSH_PATH_ENTROPY_PROG(PROG_IFCONFIG, ifconfig)
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OSSH_PATH_ENTROPY_PROG(PROG_JSTAT, jstat)
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OSSH_PATH_ENTROPY_PROG(PROG_PS, ps)
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OSSH_PATH_ENTROPY_PROG(PROG_SAR, sar)
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OSSH_PATH_ENTROPY_PROG(PROG_W, w)
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OSSH_PATH_ENTROPY_PROG(PROG_WHO, who)
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OSSH_PATH_ENTROPY_PROG(PROG_LAST, last)
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OSSH_PATH_ENTROPY_PROG(PROG_LASTLOG, lastlog)
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OSSH_PATH_ENTROPY_PROG(PROG_DF, df)
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OSSH_PATH_ENTROPY_PROG(PROG_VMSTAT, vmstat)
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OSSH_PATH_ENTROPY_PROG(PROG_UPTIME, uptime)
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OSSH_PATH_ENTROPY_PROG(PROG_IPCS, ipcs)
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OSSH_PATH_ENTROPY_PROG(PROG_TAIL, tail)
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INSTALL_SSH_PRNG_CMDS="yes"
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fi
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AC_SUBST(INSTALL_SSH_PRNG_CMDS)
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# These programs are used to gather entropy from
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OSSH_PATH_ENTROPY_PROG(PROG_LS, ls)
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OSSH_PATH_ENTROPY_PROG(PROG_NETSTAT, netstat)
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OSSH_PATH_ENTROPY_PROG(PROG_ARP, arp)
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OSSH_PATH_ENTROPY_PROG(PROG_IFCONFIG, ifconfig)
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OSSH_PATH_ENTROPY_PROG(PROG_JSTAT, jstat)
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OSSH_PATH_ENTROPY_PROG(PROG_PS, ps)
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OSSH_PATH_ENTROPY_PROG(PROG_SAR, sar)
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OSSH_PATH_ENTROPY_PROG(PROG_W, w)
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OSSH_PATH_ENTROPY_PROG(PROG_WHO, who)
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OSSH_PATH_ENTROPY_PROG(PROG_LAST, last)
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OSSH_PATH_ENTROPY_PROG(PROG_LASTLOG, lastlog)
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OSSH_PATH_ENTROPY_PROG(PROG_DF, df)
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OSSH_PATH_ENTROPY_PROG(PROG_VMSTAT, vmstat)
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OSSH_PATH_ENTROPY_PROG(PROG_UPTIME, uptime)
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OSSH_PATH_ENTROPY_PROG(PROG_IPCS, ipcs)
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OSSH_PATH_ENTROPY_PROG(PROG_TAIL, tail)
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AC_ARG_WITH(mantype,
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[ --with-mantype=man|cat|doc Set man page type],
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952
entropy.c
952
entropy.c
@ -1,5 +1,5 @@
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/*
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* Copyright (c) 2000 Damien Miller. All rights reserved.
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* Copyright (c) 2001 Damien Miller. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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@ -25,14 +25,8 @@
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#include "includes.h"
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#include <openssl/rand.h>
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#include <openssl/sha.h>
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#include <openssl/crypto.h>
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/* SunOS 4.4.4 needs this */
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#ifdef HAVE_FLOATINGPOINT_H
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# include <floatingpoint.h>
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#endif /* HAVE_FLOATINGPOINT_H */
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#include "ssh.h"
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#include "misc.h"
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#include "xmalloc.h"
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@ -40,878 +34,108 @@
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#include "pathnames.h"
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#include "log.h"
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RCSID("$Id: entropy.c,v 1.38 2001/08/06 06:51:49 djm Exp $");
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#ifndef offsetof
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# define offsetof(type, member) ((size_t) &((type *)0)->member)
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#endif
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/* Number of times to pass through command list gathering entropy */
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#define NUM_ENTROPY_RUNS 1
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/* Scale entropy estimates back by this amount on subsequent runs */
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#define SCALE_PER_RUN 10.0
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/* Minimum number of commands to be considered valid */
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#define MIN_ENTROPY_SOURCES 16
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#define WHITESPACE " \t\n"
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#ifndef RUSAGE_SELF
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# define RUSAGE_SELF 0
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#endif
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#ifndef RUSAGE_CHILDREN
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# define RUSAGE_CHILDREN 0
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#endif
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#if defined(_POSIX_SAVED_IDS) && !defined(BROKEN_SAVED_UIDS)
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# define SAVED_IDS_WORK_WITH_SETEUID
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#endif
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static void
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check_openssl_version(void)
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{
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if (SSLeay() != OPENSSL_VERSION_NUMBER)
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fatal("OpenSSL version mismatch. Built against %lx, you "
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"have %lx", OPENSSL_VERSION_NUMBER, SSLeay());
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}
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#if defined(PRNGD_SOCKET) || defined(PRNGD_PORT)
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# define USE_PRNGD
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#endif
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#if defined(USE_PRNGD) || defined(RANDOM_POOL)
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#ifdef USE_PRNGD
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/* Collect entropy from PRNGD/EGD */
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int
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get_random_bytes(unsigned char *buf, int len)
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{
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int fd;
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char msg[2];
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#ifdef PRNGD_PORT
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struct sockaddr_in addr;
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#else
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struct sockaddr_un addr;
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#endif
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int addr_len, rval, errors;
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mysig_t old_sigpipe;
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memset(&addr, '\0', sizeof(addr));
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#ifdef PRNGD_PORT
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addr.sin_family = AF_INET;
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addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
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addr.sin_port = htons(PRNGD_PORT);
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addr_len = sizeof(struct sockaddr_in);
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#else /* use IP socket PRNGD_SOCKET instead */
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/* Sanity checks */
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if (sizeof(PRNGD_SOCKET) > sizeof(addr.sun_path))
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fatal("Random pool path is too long");
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if (len > 255)
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fatal("Too many bytes to read from PRNGD");
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addr.sun_family = AF_UNIX;
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strlcpy(addr.sun_path, PRNGD_SOCKET, sizeof(addr.sun_path));
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addr_len = offsetof(struct sockaddr_un, sun_path) +
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sizeof(PRNGD_SOCKET);
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#endif
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old_sigpipe = mysignal(SIGPIPE, SIG_IGN);
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errors = rval = 0;
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reopen:
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#ifdef PRNGD_PORT
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fd = socket(addr.sin_family, SOCK_STREAM, 0);
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if (fd == -1) {
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error("Couldn't create AF_INET socket: %s", strerror(errno));
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goto done;
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}
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#else
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fd = socket(addr.sun_family, SOCK_STREAM, 0);
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if (fd == -1) {
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error("Couldn't create AF_UNIX socket: %s", strerror(errno));
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goto done;
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}
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#endif
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if (connect(fd, (struct sockaddr*)&addr, addr_len) == -1) {
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#ifdef PRNGD_PORT
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error("Couldn't connect to PRNGD port %d: %s",
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PRNGD_PORT, strerror(errno));
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#else
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error("Couldn't connect to PRNGD socket \"%s\": %s",
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addr.sun_path, strerror(errno));
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#endif
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goto done;
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}
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|
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/* Send blocking read request to PRNGD */
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msg[0] = 0x02;
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msg[1] = len;
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if (atomicio(write, fd, msg, sizeof(msg)) != sizeof(msg)) {
|
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if (errno == EPIPE && errors < 10) {
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close(fd);
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errors++;
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goto reopen;
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}
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error("Couldn't write to PRNGD socket: %s",
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strerror(errno));
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goto done;
|
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}
|
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|
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if (atomicio(read, fd, buf, len) != len) {
|
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if (errno == EPIPE && errors < 10) {
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close(fd);
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errors++;
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goto reopen;
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}
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error("Couldn't read from PRNGD socket: %s",
|
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strerror(errno));
|
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goto done;
|
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}
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rval = 1;
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done:
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mysignal(SIGPIPE, old_sigpipe);
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if (fd != -1)
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close(fd);
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return(rval);
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}
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#else /* !USE_PRNGD */
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#ifdef RANDOM_POOL
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/* Collect entropy from /dev/urandom or pipe */
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static int
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get_random_bytes(unsigned char *buf, int len)
|
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{
|
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int random_pool;
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|
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random_pool = open(RANDOM_POOL, O_RDONLY);
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if (random_pool == -1) {
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error("Couldn't open random pool \"%s\": %s",
|
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RANDOM_POOL, strerror(errno));
|
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return(0);
|
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}
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|
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if (atomicio(read, random_pool, buf, len) != len) {
|
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error("Couldn't read from random pool \"%s\": %s",
|
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RANDOM_POOL, strerror(errno));
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close(random_pool);
|
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return(0);
|
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}
|
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|
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close(random_pool);
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|
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return(1);
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}
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#endif /* RANDOM_POOL */
|
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#endif /* USE_PRNGD */
|
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|
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/*
|
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* Seed OpenSSL's random number pool from Kernel random number generator
|
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* or PRNGD/EGD
|
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* Portable OpenSSH PRNG seeding:
|
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* If OpenSSL has not "internally seeded" itself (e.g. pulled data from
|
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* /dev/random), then we execute a "ssh-rand-helper" program which
|
||||
* collects entropy and writes it to stdout. The child program must
|
||||
* write at least RANDOM_SEED_SIZE bytes. The child is run with stderr
|
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* attached, so error/debugging output should be visible.
|
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*
|
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* XXX: we should tell the child how many bytes we need.
|
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*/
|
||||
|
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#define RANDOM_SEED_SIZE 48
|
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|
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RCSID("$Id: entropy.c,v 1.39 2001/12/23 14:41:48 djm Exp $");
|
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|
||||
static uid_t original_uid, original_euid;
|
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|
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void
|
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seed_rng(void)
|
||||
{
|
||||
unsigned char buf[32];
|
||||
int devnull;
|
||||
int p[2];
|
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pid_t pid;
|
||||
int ret;
|
||||
unsigned char buf[RANDOM_SEED_SIZE];
|
||||
|
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debug("Seeding random number generator");
|
||||
|
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if (!get_random_bytes(buf, sizeof(buf))) {
|
||||
if (!RAND_status())
|
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fatal("Entropy collection failed and entropy exhausted");
|
||||
} else {
|
||||
RAND_add(buf, sizeof(buf), sizeof(buf));
|
||||
if (RAND_status() == 1) {
|
||||
debug3("RNG is ready, skipping seeding");
|
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return;
|
||||
}
|
||||
|
||||
debug3("Seeing PRNG from %s", SSH_RAND_HELPER);
|
||||
|
||||
if ((devnull = open("/dev/null", O_RDWR)) == -1)
|
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fatal("Couldn't open /dev/null: %s", strerror(errno));
|
||||
if (pipe(p) == -1)
|
||||
fatal("pipe: %s", strerror(errno));
|
||||
|
||||
if ((pid = fork()) == -1)
|
||||
fatal("Couldn't fork: %s", strerror(errno));
|
||||
if (pid == 0) {
|
||||
dup2(devnull, STDIN_FILENO);
|
||||
dup2(p[1], STDOUT_FILENO);
|
||||
/* Keep stderr open for errors */
|
||||
close(p[0]);
|
||||
close(p[1]);
|
||||
close(devnull);
|
||||
|
||||
if (original_uid != original_euid &&
|
||||
setuid(original_uid) == -1) {
|
||||
fprintf(stderr, "(rand child) setuid: %s\n",
|
||||
strerror(errno));
|
||||
_exit(1);
|
||||
}
|
||||
|
||||
execl(SSH_RAND_HELPER, "ssh-rand-helper", NULL);
|
||||
fprintf(stderr, "(rand child) Couldn't exec '%s': %s\n",
|
||||
SSH_RAND_HELPER, strerror(errno));
|
||||
_exit(1);
|
||||
}
|
||||
|
||||
close(devnull);
|
||||
close(p[1]);
|
||||
|
||||
memset(buf, '\0', sizeof(buf));
|
||||
ret = atomicio(read, p[0], buf, sizeof(buf));
|
||||
if (ret == -1)
|
||||
fatal("Couldn't read from ssh-rand-helper: %s",
|
||||
strerror(errno));
|
||||
if (ret != sizeof(buf))
|
||||
fatal("ssh-rand-helper child produced insufficient data");
|
||||
|
||||
close(p[0]);
|
||||
|
||||
if (waitpid(pid, &ret, 0) == -1)
|
||||
fatal("Couldn't wait for ssh-rand-helper completion: %s",
|
||||
strerror(errno));
|
||||
|
||||
/* We don't mind if the child exits upon a SIGPIPE */
|
||||
if (!WIFEXITED(ret) &&
|
||||
(!WIFSIGNALED(ret) || WTERMSIG(ret) != SIGPIPE))
|
||||
fatal("ssh-rand-helper terminated abnormally");
|
||||
if (WEXITSTATUS(ret) != 0)
|
||||
fatal("ssh-rand-helper exit with exit status %d", ret);
|
||||
|
||||
RAND_add(buf, sizeof(buf), sizeof(buf));
|
||||
memset(buf, '\0', sizeof(buf));
|
||||
}
|
||||
|
||||
void
|
||||
init_rng(void)
|
||||
{
|
||||
check_openssl_version();
|
||||
}
|
||||
|
||||
#else /* defined(USE_PRNGD) || defined(RANDOM_POOL) */
|
||||
|
||||
/*
|
||||
* FIXME: proper entropy estimations. All current values are guesses
|
||||
* FIXME: (ATL) do estimates at compile time?
|
||||
* FIXME: More entropy sources
|
||||
*/
|
||||
|
||||
/* slow command timeouts (all in milliseconds) */
|
||||
/* static int entropy_timeout_default = ENTROPY_TIMEOUT_MSEC; */
|
||||
static int entropy_timeout_current = ENTROPY_TIMEOUT_MSEC;
|
||||
|
||||
static int prng_seed_saved = 0;
|
||||
static int prng_initialised = 0;
|
||||
uid_t original_uid;
|
||||
|
||||
typedef struct
|
||||
{
|
||||
/* Proportion of data that is entropy */
|
||||
double rate;
|
||||
/* Counter goes positive if this command times out */
|
||||
unsigned int badness;
|
||||
/* Increases by factor of two each timeout */
|
||||
unsigned int sticky_badness;
|
||||
/* Path to executable */
|
||||
char *path;
|
||||
/* argv to pass to executable */
|
||||
char *args[5];
|
||||
/* full command string (debug) */
|
||||
char *cmdstring;
|
||||
} entropy_source_t;
|
||||
|
||||
double stir_from_system(void);
|
||||
double stir_from_programs(void);
|
||||
double stir_gettimeofday(double entropy_estimate);
|
||||
double stir_clock(double entropy_estimate);
|
||||
double stir_rusage(int who, double entropy_estimate);
|
||||
double hash_output_from_command(entropy_source_t *src, char *hash);
|
||||
|
||||
/* this is initialised from a file, by prng_read_commands() */
|
||||
entropy_source_t *entropy_sources = NULL;
|
||||
|
||||
double
|
||||
stir_from_system(void)
|
||||
{
|
||||
double total_entropy_estimate;
|
||||
long int i;
|
||||
|
||||
total_entropy_estimate = 0;
|
||||
|
||||
i = getpid();
|
||||
RAND_add(&i, sizeof(i), 0.5);
|
||||
total_entropy_estimate += 0.1;
|
||||
|
||||
i = getppid();
|
||||
RAND_add(&i, sizeof(i), 0.5);
|
||||
total_entropy_estimate += 0.1;
|
||||
|
||||
i = getuid();
|
||||
RAND_add(&i, sizeof(i), 0.0);
|
||||
i = getgid();
|
||||
RAND_add(&i, sizeof(i), 0.0);
|
||||
|
||||
total_entropy_estimate += stir_gettimeofday(1.0);
|
||||
total_entropy_estimate += stir_clock(0.5);
|
||||
total_entropy_estimate += stir_rusage(RUSAGE_SELF, 2.0);
|
||||
|
||||
return(total_entropy_estimate);
|
||||
}
|
||||
|
||||
double
|
||||
stir_from_programs(void)
|
||||
{
|
||||
int i;
|
||||
int c;
|
||||
double entropy_estimate;
|
||||
double total_entropy_estimate;
|
||||
char hash[SHA_DIGEST_LENGTH];
|
||||
|
||||
total_entropy_estimate = 0;
|
||||
for(i = 0; i < NUM_ENTROPY_RUNS; i++) {
|
||||
c = 0;
|
||||
while (entropy_sources[c].path != NULL) {
|
||||
|
||||
if (!entropy_sources[c].badness) {
|
||||
/* Hash output from command */
|
||||
entropy_estimate = hash_output_from_command(&entropy_sources[c], hash);
|
||||
|
||||
/* Scale back entropy estimate according to command's rate */
|
||||
entropy_estimate *= entropy_sources[c].rate;
|
||||
|
||||
/* Upper bound of entropy estimate is SHA_DIGEST_LENGTH */
|
||||
if (entropy_estimate > SHA_DIGEST_LENGTH)
|
||||
entropy_estimate = SHA_DIGEST_LENGTH;
|
||||
|
||||
/* Scale back estimates for subsequent passes through list */
|
||||
entropy_estimate /= SCALE_PER_RUN * (i + 1.0);
|
||||
|
||||
/* Stir it in */
|
||||
RAND_add(hash, sizeof(hash), entropy_estimate);
|
||||
|
||||
debug3("Got %0.2f bytes of entropy from '%s'", entropy_estimate,
|
||||
entropy_sources[c].cmdstring);
|
||||
|
||||
total_entropy_estimate += entropy_estimate;
|
||||
|
||||
/* Execution times should be a little unpredictable */
|
||||
total_entropy_estimate += stir_gettimeofday(0.05);
|
||||
total_entropy_estimate += stir_clock(0.05);
|
||||
total_entropy_estimate += stir_rusage(RUSAGE_SELF, 0.1);
|
||||
total_entropy_estimate += stir_rusage(RUSAGE_CHILDREN, 0.1);
|
||||
} else {
|
||||
debug2("Command '%s' disabled (badness %d)",
|
||||
entropy_sources[c].cmdstring, entropy_sources[c].badness);
|
||||
|
||||
if (entropy_sources[c].badness > 0)
|
||||
entropy_sources[c].badness--;
|
||||
}
|
||||
|
||||
c++;
|
||||
}
|
||||
}
|
||||
|
||||
return(total_entropy_estimate);
|
||||
}
|
||||
|
||||
double
|
||||
stir_gettimeofday(double entropy_estimate)
|
||||
{
|
||||
struct timeval tv;
|
||||
|
||||
if (gettimeofday(&tv, NULL) == -1)
|
||||
fatal("Couldn't gettimeofday: %s", strerror(errno));
|
||||
|
||||
RAND_add(&tv, sizeof(tv), entropy_estimate);
|
||||
|
||||
return(entropy_estimate);
|
||||
}
|
||||
|
||||
double
|
||||
stir_clock(double entropy_estimate)
|
||||
{
|
||||
#ifdef HAVE_CLOCK
|
||||
clock_t c;
|
||||
|
||||
c = clock();
|
||||
RAND_add(&c, sizeof(c), entropy_estimate);
|
||||
|
||||
return(entropy_estimate);
|
||||
#else /* _HAVE_CLOCK */
|
||||
return(0);
|
||||
#endif /* _HAVE_CLOCK */
|
||||
}
|
||||
|
||||
double
|
||||
stir_rusage(int who, double entropy_estimate)
|
||||
{
|
||||
#ifdef HAVE_GETRUSAGE
|
||||
struct rusage ru;
|
||||
|
||||
if (getrusage(who, &ru) == -1)
|
||||
return(0);
|
||||
|
||||
RAND_add(&ru, sizeof(ru), entropy_estimate);
|
||||
|
||||
return(entropy_estimate);
|
||||
#else /* _HAVE_GETRUSAGE */
|
||||
return(0);
|
||||
#endif /* _HAVE_GETRUSAGE */
|
||||
}
|
||||
|
||||
|
||||
static int
|
||||
_get_timeval_msec_difference(struct timeval *t1, struct timeval *t2) {
|
||||
int secdiff, usecdiff;
|
||||
|
||||
secdiff = t2->tv_sec - t1->tv_sec;
|
||||
usecdiff = (secdiff*1000000) + (t2->tv_usec - t1->tv_usec);
|
||||
return (int)(usecdiff / 1000);
|
||||
}
|
||||
|
||||
double
|
||||
hash_output_from_command(entropy_source_t *src, char *hash)
|
||||
{
|
||||
static int devnull = -1;
|
||||
int p[2];
|
||||
fd_set rdset;
|
||||
int cmd_eof = 0, error_abort = 0;
|
||||
struct timeval tv_start, tv_current;
|
||||
int msec_elapsed = 0;
|
||||
pid_t pid;
|
||||
int status;
|
||||
char buf[16384];
|
||||
int bytes_read;
|
||||
int total_bytes_read;
|
||||
SHA_CTX sha;
|
||||
|
||||
debug3("Reading output from \'%s\'", src->cmdstring);
|
||||
|
||||
if (devnull == -1) {
|
||||
devnull = open("/dev/null", O_RDWR);
|
||||
if (devnull == -1)
|
||||
fatal("Couldn't open /dev/null: %s", strerror(errno));
|
||||
}
|
||||
|
||||
if (pipe(p) == -1)
|
||||
fatal("Couldn't open pipe: %s", strerror(errno));
|
||||
|
||||
(void)gettimeofday(&tv_start, NULL); /* record start time */
|
||||
|
||||
switch (pid = fork()) {
|
||||
case -1: /* Error */
|
||||
close(p[0]);
|
||||
close(p[1]);
|
||||
fatal("Couldn't fork: %s", strerror(errno));
|
||||
/* NOTREACHED */
|
||||
case 0: /* Child */
|
||||
dup2(devnull, STDIN_FILENO);
|
||||
dup2(p[1], STDOUT_FILENO);
|
||||
dup2(p[1], STDERR_FILENO);
|
||||
close(p[0]);
|
||||
close(p[1]);
|
||||
close(devnull);
|
||||
|
||||
setuid(original_uid);
|
||||
execv(src->path, (char**)(src->args));
|
||||
debug("(child) Couldn't exec '%s': %s", src->cmdstring,
|
||||
strerror(errno));
|
||||
_exit(-1);
|
||||
default: /* Parent */
|
||||
break;
|
||||
}
|
||||
|
||||
RAND_add(&pid, sizeof(&pid), 0.0);
|
||||
|
||||
close(p[1]);
|
||||
|
||||
/* Hash output from child */
|
||||
SHA1_Init(&sha);
|
||||
total_bytes_read = 0;
|
||||
|
||||
while (!error_abort && !cmd_eof) {
|
||||
int ret;
|
||||
struct timeval tv;
|
||||
int msec_remaining;
|
||||
|
||||
(void) gettimeofday(&tv_current, 0);
|
||||
msec_elapsed = _get_timeval_msec_difference(&tv_start, &tv_current);
|
||||
if (msec_elapsed >= entropy_timeout_current) {
|
||||
error_abort=1;
|
||||
continue;
|
||||
}
|
||||
msec_remaining = entropy_timeout_current - msec_elapsed;
|
||||
|
||||
FD_ZERO(&rdset);
|
||||
FD_SET(p[0], &rdset);
|
||||
tv.tv_sec = msec_remaining / 1000;
|
||||
tv.tv_usec = (msec_remaining % 1000) * 1000;
|
||||
|
||||
ret = select(p[0]+1, &rdset, NULL, NULL, &tv);
|
||||
|
||||
RAND_add(&tv, sizeof(tv), 0.0);
|
||||
|
||||
switch (ret) {
|
||||
case 0:
|
||||
/* timer expired */
|
||||
error_abort = 1;
|
||||
break;
|
||||
case 1:
|
||||
/* command input */
|
||||
do {
|
||||
bytes_read = read(p[0], buf, sizeof(buf));
|
||||
} while (bytes_read == -1 && errno == EINTR);
|
||||
RAND_add(&bytes_read, sizeof(&bytes_read), 0.0);
|
||||
if (bytes_read == -1) {
|
||||
error_abort = 1;
|
||||
break;
|
||||
} else if (bytes_read) {
|
||||
SHA1_Update(&sha, buf, bytes_read);
|
||||
total_bytes_read += bytes_read;
|
||||
} else {
|
||||
cmd_eof = 1;
|
||||
}
|
||||
break;
|
||||
case -1:
|
||||
default:
|
||||
/* error */
|
||||
debug("Command '%s': select() failed: %s", src->cmdstring,
|
||||
strerror(errno));
|
||||
error_abort = 1;
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
SHA1_Final(hash, &sha);
|
||||
|
||||
close(p[0]);
|
||||
|
||||
debug3("Time elapsed: %d msec", msec_elapsed);
|
||||
|
||||
if (waitpid(pid, &status, 0) == -1) {
|
||||
error("Couldn't wait for child '%s' completion: %s", src->cmdstring,
|
||||
strerror(errno));
|
||||
return(0.0);
|
||||
}
|
||||
|
||||
RAND_add(&status, sizeof(&status), 0.0);
|
||||
|
||||
if (error_abort) {
|
||||
/* closing p[0] on timeout causes the entropy command to
|
||||
* SIGPIPE. Take whatever output we got, and mark this command
|
||||
* as slow */
|
||||
debug2("Command '%s' timed out", src->cmdstring);
|
||||
src->sticky_badness *= 2;
|
||||
src->badness = src->sticky_badness;
|
||||
return(total_bytes_read);
|
||||
}
|
||||
|
||||
if (WIFEXITED(status)) {
|
||||
if (WEXITSTATUS(status)==0) {
|
||||
return(total_bytes_read);
|
||||
} else {
|
||||
debug2("Command '%s' exit status was %d", src->cmdstring,
|
||||
WEXITSTATUS(status));
|
||||
src->badness = src->sticky_badness = 128;
|
||||
return (0.0);
|
||||
}
|
||||
} else if (WIFSIGNALED(status)) {
|
||||
debug2("Command '%s' returned on uncaught signal %d !", src->cmdstring,
|
||||
status);
|
||||
src->badness = src->sticky_badness = 128;
|
||||
return(0.0);
|
||||
} else
|
||||
return(0.0);
|
||||
}
|
||||
|
||||
/*
|
||||
* prng seedfile functions
|
||||
*/
|
||||
int
|
||||
prng_check_seedfile(char *filename) {
|
||||
|
||||
struct stat st;
|
||||
|
||||
/* FIXME raceable: eg replace seed between this stat and subsequent open */
|
||||
/* Not such a problem because we don't trust the seed file anyway */
|
||||
if (lstat(filename, &st) == -1) {
|
||||
/* Give up on hard errors */
|
||||
if (errno != ENOENT)
|
||||
debug("WARNING: Couldn't stat random seed file \"%s\": %s",
|
||||
filename, strerror(errno));
|
||||
|
||||
return(0);
|
||||
}
|
||||
|
||||
/* regular file? */
|
||||
if (!S_ISREG(st.st_mode))
|
||||
fatal("PRNG seedfile %.100s is not a regular file", filename);
|
||||
|
||||
/* mode 0600, owned by root or the current user? */
|
||||
if (((st.st_mode & 0177) != 0) || !(st.st_uid == original_uid)) {
|
||||
debug("WARNING: PRNG seedfile %.100s must be mode 0600, owned by uid %d",
|
||||
filename, getuid());
|
||||
return(0);
|
||||
}
|
||||
|
||||
return(1);
|
||||
}
|
||||
|
||||
void
|
||||
prng_write_seedfile(void) {
|
||||
int fd;
|
||||
char seed[1024];
|
||||
char filename[1024];
|
||||
struct passwd *pw;
|
||||
|
||||
/* Don't bother if we have already saved a seed */
|
||||
if (prng_seed_saved)
|
||||
return;
|
||||
|
||||
setuid(original_uid);
|
||||
|
||||
prng_seed_saved = 1;
|
||||
|
||||
pw = getpwuid(original_uid);
|
||||
if (pw == NULL)
|
||||
fatal("Couldn't get password entry for current user (%i): %s",
|
||||
original_uid, strerror(errno));
|
||||
|
||||
/* Try to ensure that the parent directory is there */
|
||||
snprintf(filename, sizeof(filename), "%.512s/%s", pw->pw_dir,
|
||||
_PATH_SSH_USER_DIR);
|
||||
mkdir(filename, 0700);
|
||||
|
||||
snprintf(filename, sizeof(filename), "%.512s/%s", pw->pw_dir,
|
||||
SSH_PRNG_SEED_FILE);
|
||||
|
||||
debug("writing PRNG seed to file %.100s", filename);
|
||||
|
||||
RAND_bytes(seed, sizeof(seed));
|
||||
|
||||
/* Don't care if the seed doesn't exist */
|
||||
prng_check_seedfile(filename);
|
||||
|
||||
if ((fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0600)) == -1) {
|
||||
debug("WARNING: couldn't access PRNG seedfile %.100s (%.100s)",
|
||||
filename, strerror(errno));
|
||||
} else {
|
||||
if (atomicio(write, fd, &seed, sizeof(seed)) != sizeof(seed))
|
||||
fatal("problem writing PRNG seedfile %.100s (%.100s)", filename,
|
||||
strerror(errno));
|
||||
|
||||
close(fd);
|
||||
}
|
||||
}
|
||||
|
||||
void
|
||||
prng_read_seedfile(void) {
|
||||
int fd;
|
||||
char seed[1024];
|
||||
char filename[1024];
|
||||
struct passwd *pw;
|
||||
|
||||
pw = getpwuid(original_uid);
|
||||
if (pw == NULL)
|
||||
fatal("Couldn't get password entry for current user (%i): %s",
|
||||
original_uid, strerror(errno));
|
||||
|
||||
snprintf(filename, sizeof(filename), "%.512s/%s", pw->pw_dir,
|
||||
SSH_PRNG_SEED_FILE);
|
||||
|
||||
debug("loading PRNG seed from file %.100s", filename);
|
||||
|
||||
if (!prng_check_seedfile(filename)) {
|
||||
verbose("Random seed file not found or not valid, ignoring.");
|
||||
return;
|
||||
}
|
||||
|
||||
/* open the file and read in the seed */
|
||||
fd = open(filename, O_RDONLY);
|
||||
if (fd == -1)
|
||||
fatal("could not open PRNG seedfile %.100s (%.100s)", filename,
|
||||
strerror(errno));
|
||||
|
||||
if (atomicio(read, fd, &seed, sizeof(seed)) != sizeof(seed)) {
|
||||
verbose("invalid or short read from PRNG seedfile %.100s - ignoring",
|
||||
filename);
|
||||
memset(seed, '\0', sizeof(seed));
|
||||
}
|
||||
close(fd);
|
||||
|
||||
/* stir in the seed, with estimated entropy zero */
|
||||
RAND_add(&seed, sizeof(seed), 0.0);
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* entropy command initialisation functions
|
||||
*/
|
||||
int
|
||||
prng_read_commands(char *cmdfilename)
|
||||
{
|
||||
FILE *f;
|
||||
char *cp;
|
||||
char line[1024];
|
||||
char cmd[1024];
|
||||
char path[256];
|
||||
int linenum;
|
||||
int num_cmds = 64;
|
||||
int cur_cmd = 0;
|
||||
double est;
|
||||
entropy_source_t *entcmd;
|
||||
|
||||
f = fopen(cmdfilename, "r");
|
||||
if (!f) {
|
||||
fatal("couldn't read entropy commands file %.100s: %.100s",
|
||||
cmdfilename, strerror(errno));
|
||||
}
|
||||
|
||||
entcmd = (entropy_source_t *)xmalloc(num_cmds * sizeof(entropy_source_t));
|
||||
memset(entcmd, '\0', num_cmds * sizeof(entropy_source_t));
|
||||
|
||||
/* Read in file */
|
||||
linenum = 0;
|
||||
while (fgets(line, sizeof(line), f)) {
|
||||
int arg;
|
||||
char *argv;
|
||||
|
||||
linenum++;
|
||||
|
||||
/* skip leading whitespace, test for blank line or comment */
|
||||
cp = line + strspn(line, WHITESPACE);
|
||||
if ((*cp == 0) || (*cp == '#'))
|
||||
continue; /* done with this line */
|
||||
|
||||
/* First non-whitespace char should be double quote delimiting */
|
||||
/* commandline */
|
||||
if (*cp != '"') {
|
||||
error("bad entropy command, %.100s line %d", cmdfilename,
|
||||
linenum);
|
||||
continue;
|
||||
}
|
||||
|
||||
/* first token, command args (incl. argv[0]) in double quotes */
|
||||
cp = strtok(cp, "\"");
|
||||
if (cp == NULL) {
|
||||
error("missing or bad command string, %.100s line %d -- ignored",
|
||||
cmdfilename, linenum);
|
||||
continue;
|
||||
}
|
||||
strlcpy(cmd, cp, sizeof(cmd));
|
||||
|
||||
/* second token, full command path */
|
||||
if ((cp = strtok(NULL, WHITESPACE)) == NULL) {
|
||||
error("missing command path, %.100s line %d -- ignored",
|
||||
cmdfilename, linenum);
|
||||
continue;
|
||||
}
|
||||
|
||||
/* did configure mark this as dead? */
|
||||
if (strncmp("undef", cp, 5) == 0)
|
||||
continue;
|
||||
|
||||
strlcpy(path, cp, sizeof(path));
|
||||
|
||||
/* third token, entropy rate estimate for this command */
|
||||
if ((cp = strtok(NULL, WHITESPACE)) == NULL) {
|
||||
error("missing entropy estimate, %.100s line %d -- ignored",
|
||||
cmdfilename, linenum);
|
||||
continue;
|
||||
}
|
||||
est = strtod(cp, &argv);
|
||||
|
||||
/* end of line */
|
||||
if ((cp = strtok(NULL, WHITESPACE)) != NULL) {
|
||||
error("garbage at end of line %d in %.100s -- ignored", linenum,
|
||||
cmdfilename);
|
||||
continue;
|
||||
}
|
||||
|
||||
/* save the command for debug messages */
|
||||
entcmd[cur_cmd].cmdstring = xstrdup(cmd);
|
||||
|
||||
/* split the command args */
|
||||
cp = strtok(cmd, WHITESPACE);
|
||||
arg = 0;
|
||||
argv = NULL;
|
||||
do {
|
||||
char *s = (char*)xmalloc(strlen(cp) + 1);
|
||||
strncpy(s, cp, strlen(cp) + 1);
|
||||
entcmd[cur_cmd].args[arg] = s;
|
||||
arg++;
|
||||
} while ((arg < 5) && (cp = strtok(NULL, WHITESPACE)));
|
||||
|
||||
if (strtok(NULL, WHITESPACE))
|
||||
error("ignored extra command elements (max 5), %.100s line %d",
|
||||
cmdfilename, linenum);
|
||||
|
||||
/* Copy the command path and rate estimate */
|
||||
entcmd[cur_cmd].path = xstrdup(path);
|
||||
entcmd[cur_cmd].rate = est;
|
||||
|
||||
/* Initialise other values */
|
||||
entcmd[cur_cmd].sticky_badness = 1;
|
||||
|
||||
cur_cmd++;
|
||||
|
||||
/* If we've filled the array, reallocate it twice the size */
|
||||
/* Do this now because even if this we're on the last command,
|
||||
we need another slot to mark the last entry */
|
||||
if (cur_cmd == num_cmds) {
|
||||
num_cmds *= 2;
|
||||
entcmd = xrealloc(entcmd, num_cmds * sizeof(entropy_source_t));
|
||||
}
|
||||
}
|
||||
|
||||
/* zero the last entry */
|
||||
memset(&entcmd[cur_cmd], '\0', sizeof(entropy_source_t));
|
||||
|
||||
/* trim to size */
|
||||
entropy_sources = xrealloc(entcmd, (cur_cmd+1) * sizeof(entropy_source_t));
|
||||
|
||||
debug("Loaded %d entropy commands from %.100s", cur_cmd, cmdfilename);
|
||||
|
||||
return (cur_cmd >= MIN_ENTROPY_SOURCES);
|
||||
}
|
||||
|
||||
/*
|
||||
* Write a keyfile at exit
|
||||
*/
|
||||
void
|
||||
prng_seed_cleanup(void *junk)
|
||||
{
|
||||
prng_write_seedfile();
|
||||
}
|
||||
|
||||
/*
|
||||
* Conditionally Seed OpenSSL's random number pool from
|
||||
* syscalls and program output
|
||||
*/
|
||||
void
|
||||
seed_rng(void)
|
||||
{
|
||||
mysig_t old_sigchld_handler;
|
||||
|
||||
if (!prng_initialised)
|
||||
fatal("RNG not initialised");
|
||||
|
||||
/* Make sure some other sigchld handler doesn't reap our entropy */
|
||||
/* commands */
|
||||
old_sigchld_handler = mysignal(SIGCHLD, SIG_DFL);
|
||||
|
||||
debug("Seeded RNG with %i bytes from programs",
|
||||
(int)stir_from_programs());
|
||||
debug("Seeded RNG with %i bytes from system calls",
|
||||
(int)stir_from_system());
|
||||
|
||||
if (!RAND_status())
|
||||
fatal("Not enough entropy in RNG");
|
||||
|
||||
mysignal(SIGCHLD, old_sigchld_handler);
|
||||
|
||||
if (!RAND_status())
|
||||
fatal("Couldn't initialise builtin random number generator -- exiting.");
|
||||
}
|
||||
|
||||
void
|
||||
init_rng(void)
|
||||
{
|
||||
int original_euid;
|
||||
|
||||
check_openssl_version();
|
||||
|
||||
original_uid = getuid();
|
||||
original_euid = geteuid();
|
||||
|
||||
/* Read in collection commands */
|
||||
if (!prng_read_commands(SSH_PRNG_COMMAND_FILE))
|
||||
fatal("PRNG initialisation failed -- exiting.");
|
||||
|
||||
/* Set ourselves up to save a seed upon exit */
|
||||
prng_seed_saved = 0;
|
||||
|
||||
/* Give up privs while reading seed file */
|
||||
#ifdef SAVED_IDS_WORK_WITH_SETEUID
|
||||
if ((original_uid != original_euid) && (seteuid(original_uid) == -1))
|
||||
fatal("Couldn't give up privileges");
|
||||
#else /* SAVED_IDS_WORK_WITH_SETEUID */
|
||||
/*
|
||||
* Propagate the privileged uid to all of our uids.
|
||||
* Set the effective uid to the given (unprivileged) uid.
|
||||
* OpenSSL version numbers: MNNFFPPS: major minor fix patch status
|
||||
* We match major, minor, fix and status (not patch)
|
||||
*/
|
||||
if (original_uid != original_euid && (setuid(original_euid) == -1 ||
|
||||
seteuid(original_uid) == -1))
|
||||
fatal("Couldn't give up privileges");
|
||||
#endif /* SAVED_IDS_WORK_WITH_SETEUID */
|
||||
if ((SSLeay() ^ OPENSSL_VERSION_NUMBER) & ~0xff0L)
|
||||
fatal("OpenSSL version mismatch. Built against %lx, you "
|
||||
"have %lx", OPENSSL_VERSION_NUMBER, SSLeay());
|
||||
|
||||
prng_read_seedfile();
|
||||
|
||||
#ifdef SAVED_IDS_WORK_WITH_SETEUID
|
||||
if ((original_uid != original_euid) && (seteuid(original_euid) == -1))
|
||||
fatal("Couldn't restore privileges");
|
||||
#else /* SAVED_IDS_WORK_WITH_SETEUID */
|
||||
/*
|
||||
* We are unable to restore the real uid to its unprivileged value.
|
||||
* Propagate the real uid (usually more privileged) to effective uid
|
||||
* as well.
|
||||
*/
|
||||
if (original_uid != original_euid && (seteuid(original_euid) == -1 ||
|
||||
setuid(original_uid) == -1))
|
||||
fatal("Couldn't restore privileges");
|
||||
#endif /* SAVED_IDS_WORK_WITH_SETEUID */
|
||||
|
||||
fatal_add_cleanup(prng_seed_cleanup, NULL);
|
||||
atexit(prng_write_seedfile);
|
||||
|
||||
prng_initialised = 1;
|
||||
if ((original_uid = getuid()) == -1)
|
||||
fatal("getuid: %s", strerror(errno));
|
||||
if ((original_euid = geteuid()) == -1)
|
||||
fatal("geteuid: %s", strerror(errno));
|
||||
}
|
||||
|
||||
#endif /* defined(USE_PRNGD) || defined(RANDOM_POOL) */
|
||||
|
||||
10
pathnames.h
10
pathnames.h
@ -154,13 +154,3 @@
|
||||
#ifndef ASKPASS_PROGRAM
|
||||
#define ASKPASS_PROGRAM "/usr/lib/ssh/ssh-askpass"
|
||||
#endif /* ASKPASS_PROGRAM */
|
||||
|
||||
/*
|
||||
* Relevant only when using builtin PRNG.
|
||||
*/
|
||||
#ifndef SSH_PRNG_SEED_FILE
|
||||
# define SSH_PRNG_SEED_FILE _PATH_SSH_USER_DIR"/prng_seed"
|
||||
#endif /* SSH_PRNG_SEED_FILE */
|
||||
#ifndef SSH_PRNG_COMMAND_FILE
|
||||
# define SSH_PRNG_COMMAND_FILE ETCDIR "/ssh_prng_cmds"
|
||||
#endif /* SSH_PRNG_COMMAND_FILE */
|
||||
|
||||
805
ssh-rand-helper.c
Normal file
805
ssh-rand-helper.c
Normal file
@ -0,0 +1,805 @@
|
||||
/*
|
||||
* Copyright (c) 2001 Damien Miller. 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.
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
|
||||
*/
|
||||
|
||||
#include "includes.h"
|
||||
|
||||
#include <openssl/rand.h>
|
||||
#include <openssl/sha.h>
|
||||
#include <openssl/crypto.h>
|
||||
|
||||
/* SunOS 4.4.4 needs this */
|
||||
#ifdef HAVE_FLOATINGPOINT_H
|
||||
# include <floatingpoint.h>
|
||||
#endif /* HAVE_FLOATINGPOINT_H */
|
||||
|
||||
#include "misc.h"
|
||||
#include "xmalloc.h"
|
||||
#include "atomicio.h"
|
||||
#include "pathnames.h"
|
||||
#include "log.h"
|
||||
|
||||
RCSID("$Id: ssh-rand-helper.c,v 1.1 2001/12/23 14:41:48 djm Exp $");
|
||||
|
||||
#define RANDOM_SEED_SIZE 48
|
||||
|
||||
#ifndef SSH_PRNG_SEED_FILE
|
||||
# define SSH_PRNG_SEED_FILE _PATH_SSH_USER_DIR"/prng_seed"
|
||||
#endif /* SSH_PRNG_SEED_FILE */
|
||||
#ifndef SSH_PRNG_COMMAND_FILE
|
||||
# define SSH_PRNG_COMMAND_FILE ETCDIR "/ssh_prng_cmds"
|
||||
#endif /* SSH_PRNG_COMMAND_FILE */
|
||||
|
||||
|
||||
#ifndef offsetof
|
||||
# define offsetof(type, member) ((size_t) &((type *)0)->member)
|
||||
#endif
|
||||
|
||||
/* Number of times to pass through command list gathering entropy */
|
||||
#define NUM_ENTROPY_RUNS 1
|
||||
|
||||
/* Scale entropy estimates back by this amount on subsequent runs */
|
||||
#define SCALE_PER_RUN 10.0
|
||||
|
||||
/* Minimum number of commands to be considered valid */
|
||||
#define MIN_ENTROPY_SOURCES 16
|
||||
|
||||
#define WHITESPACE " \t\n"
|
||||
|
||||
#ifndef RUSAGE_SELF
|
||||
# define RUSAGE_SELF 0
|
||||
#endif
|
||||
#ifndef RUSAGE_CHILDREN
|
||||
# define RUSAGE_CHILDREN 0
|
||||
#endif
|
||||
|
||||
#if defined(PRNGD_SOCKET) || defined(PRNGD_PORT)
|
||||
# define USE_PRNGD
|
||||
#endif
|
||||
|
||||
#ifdef USE_PRNGD
|
||||
/* Collect entropy from PRNGD/EGD */
|
||||
int
|
||||
get_random_bytes(unsigned char *buf, int len)
|
||||
{
|
||||
int fd;
|
||||
char msg[2];
|
||||
#ifdef PRNGD_PORT
|
||||
struct sockaddr_in addr;
|
||||
#else
|
||||
struct sockaddr_un addr;
|
||||
#endif
|
||||
int addr_len, rval, errors;
|
||||
mysig_t old_sigpipe;
|
||||
|
||||
if (len > 255)
|
||||
fatal("Too many bytes to read from PRNGD");
|
||||
|
||||
memset(&addr, '\0', sizeof(addr));
|
||||
|
||||
#ifdef PRNGD_PORT
|
||||
addr.sin_family = AF_INET;
|
||||
addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
|
||||
addr.sin_port = htons(PRNGD_PORT);
|
||||
addr_len = sizeof(struct sockaddr_in);
|
||||
#else /* use IP socket PRNGD_SOCKET instead */
|
||||
/* Sanity checks */
|
||||
if (sizeof(PRNGD_SOCKET) > sizeof(addr.sun_path))
|
||||
fatal("Random pool path is too long");
|
||||
|
||||
addr.sun_family = AF_UNIX;
|
||||
strlcpy(addr.sun_path, PRNGD_SOCKET, sizeof(addr.sun_path));
|
||||
addr_len = offsetof(struct sockaddr_un, sun_path) +
|
||||
sizeof(PRNGD_SOCKET);
|
||||
#endif
|
||||
|
||||
old_sigpipe = mysignal(SIGPIPE, SIG_IGN);
|
||||
|
||||
errors = rval = 0;
|
||||
reopen:
|
||||
#ifdef PRNGD_PORT
|
||||
fd = socket(addr.sin_family, SOCK_STREAM, 0);
|
||||
if (fd == -1) {
|
||||
error("Couldn't create AF_INET socket: %s", strerror(errno));
|
||||
goto done;
|
||||
}
|
||||
#else
|
||||
fd = socket(addr.sun_family, SOCK_STREAM, 0);
|
||||
if (fd == -1) {
|
||||
error("Couldn't create AF_UNIX socket: %s", strerror(errno));
|
||||
goto done;
|
||||
}
|
||||
#endif
|
||||
|
||||
if (connect(fd, (struct sockaddr*)&addr, addr_len) == -1) {
|
||||
#ifdef PRNGD_PORT
|
||||
error("Couldn't connect to PRNGD port %d: %s",
|
||||
PRNGD_PORT, strerror(errno));
|
||||
#else
|
||||
error("Couldn't connect to PRNGD socket \"%s\": %s",
|
||||
addr.sun_path, strerror(errno));
|
||||
#endif
|
||||
goto done;
|
||||
}
|
||||
|
||||
/* Send blocking read request to PRNGD */
|
||||
msg[0] = 0x02;
|
||||
msg[1] = len;
|
||||
|
||||
if (atomicio(write, fd, msg, sizeof(msg)) != sizeof(msg)) {
|
||||
if (errno == EPIPE && errors < 10) {
|
||||
close(fd);
|
||||
errors++;
|
||||
goto reopen;
|
||||
}
|
||||
error("Couldn't write to PRNGD socket: %s",
|
||||
strerror(errno));
|
||||
goto done;
|
||||
}
|
||||
|
||||
if (atomicio(read, fd, buf, len) != len) {
|
||||
if (errno == EPIPE && errors < 10) {
|
||||
close(fd);
|
||||
errors++;
|
||||
goto reopen;
|
||||
}
|
||||
error("Couldn't read from PRNGD socket: %s",
|
||||
strerror(errno));
|
||||
goto done;
|
||||
}
|
||||
|
||||
rval = 1;
|
||||
done:
|
||||
mysignal(SIGPIPE, old_sigpipe);
|
||||
if (fd != -1)
|
||||
close(fd);
|
||||
return(rval);
|
||||
}
|
||||
|
||||
static void
|
||||
seed_openssl_rng(void)
|
||||
{
|
||||
unsigned char buf[RANDOM_SEED_SIZE];
|
||||
|
||||
if (!get_random_bytes(buf, sizeof(buf)))
|
||||
fatal("Entropy collection failed");
|
||||
|
||||
RAND_add(buf, sizeof(buf), sizeof(buf));
|
||||
memset(buf, '\0', sizeof(buf));
|
||||
}
|
||||
|
||||
#else /* USE_PRNGD */
|
||||
|
||||
/*
|
||||
* FIXME: proper entropy estimations. All current values are guesses
|
||||
* FIXME: (ATL) do estimates at compile time?
|
||||
* FIXME: More entropy sources
|
||||
*/
|
||||
|
||||
/* slow command timeouts (all in milliseconds) */
|
||||
/* static int entropy_timeout_default = ENTROPY_TIMEOUT_MSEC; */
|
||||
static int entropy_timeout_current = ENTROPY_TIMEOUT_MSEC;
|
||||
|
||||
typedef struct
|
||||
{
|
||||
/* Proportion of data that is entropy */
|
||||
double rate;
|
||||
/* Counter goes positive if this command times out */
|
||||
unsigned int badness;
|
||||
/* Increases by factor of two each timeout */
|
||||
unsigned int sticky_badness;
|
||||
/* Path to executable */
|
||||
char *path;
|
||||
/* argv to pass to executable */
|
||||
char *args[5];
|
||||
/* full command string (debug) */
|
||||
char *cmdstring;
|
||||
} entropy_source_t;
|
||||
|
||||
double stir_from_system(void);
|
||||
double stir_from_programs(void);
|
||||
double stir_gettimeofday(double entropy_estimate);
|
||||
double stir_clock(double entropy_estimate);
|
||||
double stir_rusage(int who, double entropy_estimate);
|
||||
double hash_output_from_command(entropy_source_t *src, char *hash);
|
||||
|
||||
/* this is initialised from a file, by prng_read_commands() */
|
||||
entropy_source_t *entropy_sources = NULL;
|
||||
|
||||
double
|
||||
stir_from_system(void)
|
||||
{
|
||||
double total_entropy_estimate;
|
||||
long int i;
|
||||
|
||||
total_entropy_estimate = 0;
|
||||
|
||||
i = getpid();
|
||||
RAND_add(&i, sizeof(i), 0.5);
|
||||
total_entropy_estimate += 0.1;
|
||||
|
||||
i = getppid();
|
||||
RAND_add(&i, sizeof(i), 0.5);
|
||||
total_entropy_estimate += 0.1;
|
||||
|
||||
i = getuid();
|
||||
RAND_add(&i, sizeof(i), 0.0);
|
||||
i = getgid();
|
||||
RAND_add(&i, sizeof(i), 0.0);
|
||||
|
||||
total_entropy_estimate += stir_gettimeofday(1.0);
|
||||
total_entropy_estimate += stir_clock(0.5);
|
||||
total_entropy_estimate += stir_rusage(RUSAGE_SELF, 2.0);
|
||||
|
||||
return(total_entropy_estimate);
|
||||
}
|
||||
|
||||
double
|
||||
stir_from_programs(void)
|
||||
{
|
||||
int i;
|
||||
int c;
|
||||
double entropy_estimate;
|
||||
double total_entropy_estimate;
|
||||
char hash[SHA_DIGEST_LENGTH];
|
||||
|
||||
total_entropy_estimate = 0;
|
||||
for(i = 0; i < NUM_ENTROPY_RUNS; i++) {
|
||||
c = 0;
|
||||
while (entropy_sources[c].path != NULL) {
|
||||
|
||||
if (!entropy_sources[c].badness) {
|
||||
/* Hash output from command */
|
||||
entropy_estimate = hash_output_from_command(&entropy_sources[c], hash);
|
||||
|
||||
/* Scale back entropy estimate according to command's rate */
|
||||
entropy_estimate *= entropy_sources[c].rate;
|
||||
|
||||
/* Upper bound of entropy estimate is SHA_DIGEST_LENGTH */
|
||||
if (entropy_estimate > SHA_DIGEST_LENGTH)
|
||||
entropy_estimate = SHA_DIGEST_LENGTH;
|
||||
|
||||
/* Scale back estimates for subsequent passes through list */
|
||||
entropy_estimate /= SCALE_PER_RUN * (i + 1.0);
|
||||
|
||||
/* Stir it in */
|
||||
RAND_add(hash, sizeof(hash), entropy_estimate);
|
||||
|
||||
debug3("Got %0.2f bytes of entropy from '%s'", entropy_estimate,
|
||||
entropy_sources[c].cmdstring);
|
||||
|
||||
total_entropy_estimate += entropy_estimate;
|
||||
|
||||
/* Execution times should be a little unpredictable */
|
||||
total_entropy_estimate += stir_gettimeofday(0.05);
|
||||
total_entropy_estimate += stir_clock(0.05);
|
||||
total_entropy_estimate += stir_rusage(RUSAGE_SELF, 0.1);
|
||||
total_entropy_estimate += stir_rusage(RUSAGE_CHILDREN, 0.1);
|
||||
} else {
|
||||
debug2("Command '%s' disabled (badness %d)",
|
||||
entropy_sources[c].cmdstring, entropy_sources[c].badness);
|
||||
|
||||
if (entropy_sources[c].badness > 0)
|
||||
entropy_sources[c].badness--;
|
||||
}
|
||||
|
||||
c++;
|
||||
}
|
||||
}
|
||||
|
||||
return(total_entropy_estimate);
|
||||
}
|
||||
|
||||
double
|
||||
stir_gettimeofday(double entropy_estimate)
|
||||
{
|
||||
struct timeval tv;
|
||||
|
||||
if (gettimeofday(&tv, NULL) == -1)
|
||||
fatal("Couldn't gettimeofday: %s", strerror(errno));
|
||||
|
||||
RAND_add(&tv, sizeof(tv), entropy_estimate);
|
||||
|
||||
return(entropy_estimate);
|
||||
}
|
||||
|
||||
double
|
||||
stir_clock(double entropy_estimate)
|
||||
{
|
||||
#ifdef HAVE_CLOCK
|
||||
clock_t c;
|
||||
|
||||
c = clock();
|
||||
RAND_add(&c, sizeof(c), entropy_estimate);
|
||||
|
||||
return(entropy_estimate);
|
||||
#else /* _HAVE_CLOCK */
|
||||
return(0);
|
||||
#endif /* _HAVE_CLOCK */
|
||||
}
|
||||
|
||||
double
|
||||
stir_rusage(int who, double entropy_estimate)
|
||||
{
|
||||
#ifdef HAVE_GETRUSAGE
|
||||
struct rusage ru;
|
||||
|
||||
if (getrusage(who, &ru) == -1)
|
||||
return(0);
|
||||
|
||||
RAND_add(&ru, sizeof(ru), entropy_estimate);
|
||||
|
||||
return(entropy_estimate);
|
||||
#else /* _HAVE_GETRUSAGE */
|
||||
return(0);
|
||||
#endif /* _HAVE_GETRUSAGE */
|
||||
}
|
||||
|
||||
|
||||
static int
|
||||
_get_timeval_msec_difference(struct timeval *t1, struct timeval *t2) {
|
||||
int secdiff, usecdiff;
|
||||
|
||||
secdiff = t2->tv_sec - t1->tv_sec;
|
||||
usecdiff = (secdiff*1000000) + (t2->tv_usec - t1->tv_usec);
|
||||
return (int)(usecdiff / 1000);
|
||||
}
|
||||
|
||||
double
|
||||
hash_output_from_command(entropy_source_t *src, char *hash)
|
||||
{
|
||||
static int devnull = -1;
|
||||
int p[2];
|
||||
fd_set rdset;
|
||||
int cmd_eof = 0, error_abort = 0;
|
||||
struct timeval tv_start, tv_current;
|
||||
int msec_elapsed = 0;
|
||||
pid_t pid;
|
||||
int status;
|
||||
char buf[16384];
|
||||
int bytes_read;
|
||||
int total_bytes_read;
|
||||
SHA_CTX sha;
|
||||
|
||||
debug3("Reading output from \'%s\'", src->cmdstring);
|
||||
|
||||
if (devnull == -1) {
|
||||
devnull = open("/dev/null", O_RDWR);
|
||||
if (devnull == -1)
|
||||
fatal("Couldn't open /dev/null: %s", strerror(errno));
|
||||
}
|
||||
|
||||
if (pipe(p) == -1)
|
||||
fatal("Couldn't open pipe: %s", strerror(errno));
|
||||
|
||||
(void)gettimeofday(&tv_start, NULL); /* record start time */
|
||||
|
||||
switch (pid = fork()) {
|
||||
case -1: /* Error */
|
||||
close(p[0]);
|
||||
close(p[1]);
|
||||
fatal("Couldn't fork: %s", strerror(errno));
|
||||
/* NOTREACHED */
|
||||
case 0: /* Child */
|
||||
dup2(devnull, STDIN_FILENO);
|
||||
dup2(p[1], STDOUT_FILENO);
|
||||
dup2(p[1], STDERR_FILENO);
|
||||
close(p[0]);
|
||||
close(p[1]);
|
||||
close(devnull);
|
||||
|
||||
execv(src->path, (char**)(src->args));
|
||||
debug("(child) Couldn't exec '%s': %s", src->cmdstring,
|
||||
strerror(errno));
|
||||
_exit(-1);
|
||||
default: /* Parent */
|
||||
break;
|
||||
}
|
||||
|
||||
RAND_add(&pid, sizeof(&pid), 0.0);
|
||||
|
||||
close(p[1]);
|
||||
|
||||
/* Hash output from child */
|
||||
SHA1_Init(&sha);
|
||||
total_bytes_read = 0;
|
||||
|
||||
while (!error_abort && !cmd_eof) {
|
||||
int ret;
|
||||
struct timeval tv;
|
||||
int msec_remaining;
|
||||
|
||||
(void) gettimeofday(&tv_current, 0);
|
||||
msec_elapsed = _get_timeval_msec_difference(&tv_start, &tv_current);
|
||||
if (msec_elapsed >= entropy_timeout_current) {
|
||||
error_abort=1;
|
||||
continue;
|
||||
}
|
||||
msec_remaining = entropy_timeout_current - msec_elapsed;
|
||||
|
||||
FD_ZERO(&rdset);
|
||||
FD_SET(p[0], &rdset);
|
||||
tv.tv_sec = msec_remaining / 1000;
|
||||
tv.tv_usec = (msec_remaining % 1000) * 1000;
|
||||
|
||||
ret = select(p[0]+1, &rdset, NULL, NULL, &tv);
|
||||
|
||||
RAND_add(&tv, sizeof(tv), 0.0);
|
||||
|
||||
switch (ret) {
|
||||
case 0:
|
||||
/* timer expired */
|
||||
error_abort = 1;
|
||||
break;
|
||||
case 1:
|
||||
/* command input */
|
||||
do {
|
||||
bytes_read = read(p[0], buf, sizeof(buf));
|
||||
} while (bytes_read == -1 && errno == EINTR);
|
||||
RAND_add(&bytes_read, sizeof(&bytes_read), 0.0);
|
||||
if (bytes_read == -1) {
|
||||
error_abort = 1;
|
||||
break;
|
||||
} else if (bytes_read) {
|
||||
SHA1_Update(&sha, buf, bytes_read);
|
||||
total_bytes_read += bytes_read;
|
||||
} else {
|
||||
cmd_eof = 1;
|
||||
}
|
||||
break;
|
||||
case -1:
|
||||
default:
|
||||
/* error */
|
||||
debug("Command '%s': select() failed: %s", src->cmdstring,
|
||||
strerror(errno));
|
||||
error_abort = 1;
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
SHA1_Final(hash, &sha);
|
||||
|
||||
close(p[0]);
|
||||
|
||||
debug3("Time elapsed: %d msec", msec_elapsed);
|
||||
|
||||
if (waitpid(pid, &status, 0) == -1) {
|
||||
error("Couldn't wait for child '%s' completion: %s", src->cmdstring,
|
||||
strerror(errno));
|
||||
return(0.0);
|
||||
}
|
||||
|
||||
RAND_add(&status, sizeof(&status), 0.0);
|
||||
|
||||
if (error_abort) {
|
||||
/* closing p[0] on timeout causes the entropy command to
|
||||
* SIGPIPE. Take whatever output we got, and mark this command
|
||||
* as slow */
|
||||
debug2("Command '%s' timed out", src->cmdstring);
|
||||
src->sticky_badness *= 2;
|
||||
src->badness = src->sticky_badness;
|
||||
return(total_bytes_read);
|
||||
}
|
||||
|
||||
if (WIFEXITED(status)) {
|
||||
if (WEXITSTATUS(status)==0) {
|
||||
return(total_bytes_read);
|
||||
} else {
|
||||
debug2("Command '%s' exit status was %d", src->cmdstring,
|
||||
WEXITSTATUS(status));
|
||||
src->badness = src->sticky_badness = 128;
|
||||
return (0.0);
|
||||
}
|
||||
} else if (WIFSIGNALED(status)) {
|
||||
debug2("Command '%s' returned on uncaught signal %d !", src->cmdstring,
|
||||
status);
|
||||
src->badness = src->sticky_badness = 128;
|
||||
return(0.0);
|
||||
} else
|
||||
return(0.0);
|
||||
}
|
||||
|
||||
/*
|
||||
* prng seedfile functions
|
||||
*/
|
||||
int
|
||||
prng_check_seedfile(char *filename) {
|
||||
|
||||
struct stat st;
|
||||
|
||||
/* FIXME raceable: eg replace seed between this stat and subsequent open */
|
||||
/* Not such a problem because we don't trust the seed file anyway */
|
||||
if (lstat(filename, &st) == -1) {
|
||||
/* Give up on hard errors */
|
||||
if (errno != ENOENT)
|
||||
debug("WARNING: Couldn't stat random seed file \"%s\": %s",
|
||||
filename, strerror(errno));
|
||||
|
||||
return(0);
|
||||
}
|
||||
|
||||
/* regular file? */
|
||||
if (!S_ISREG(st.st_mode))
|
||||
fatal("PRNG seedfile %.100s is not a regular file", filename);
|
||||
|
||||
/* mode 0600, owned by root or the current user? */
|
||||
if (((st.st_mode & 0177) != 0) || !(st.st_uid == getuid())) {
|
||||
debug("WARNING: PRNG seedfile %.100s must be mode 0600, owned by uid %d",
|
||||
filename, getuid());
|
||||
return(0);
|
||||
}
|
||||
|
||||
return(1);
|
||||
}
|
||||
|
||||
void
|
||||
prng_write_seedfile(void) {
|
||||
int fd;
|
||||
char seed[1024];
|
||||
char filename[1024];
|
||||
struct passwd *pw;
|
||||
|
||||
pw = getpwuid(getuid());
|
||||
if (pw == NULL)
|
||||
fatal("Couldn't get password entry for current user (%i): %s",
|
||||
getuid(), strerror(errno));
|
||||
|
||||
/* Try to ensure that the parent directory is there */
|
||||
snprintf(filename, sizeof(filename), "%.512s/%s", pw->pw_dir,
|
||||
_PATH_SSH_USER_DIR);
|
||||
mkdir(filename, 0700);
|
||||
|
||||
snprintf(filename, sizeof(filename), "%.512s/%s", pw->pw_dir,
|
||||
SSH_PRNG_SEED_FILE);
|
||||
|
||||
debug("writing PRNG seed to file %.100s", filename);
|
||||
|
||||
RAND_bytes(seed, sizeof(seed));
|
||||
|
||||
/* Don't care if the seed doesn't exist */
|
||||
prng_check_seedfile(filename);
|
||||
|
||||
if ((fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0600)) == -1) {
|
||||
debug("WARNING: couldn't access PRNG seedfile %.100s (%.100s)",
|
||||
filename, strerror(errno));
|
||||
} else {
|
||||
if (atomicio(write, fd, &seed, sizeof(seed)) != sizeof(seed))
|
||||
fatal("problem writing PRNG seedfile %.100s (%.100s)", filename,
|
||||
strerror(errno));
|
||||
close(fd);
|
||||
}
|
||||
}
|
||||
|
||||
void
|
||||
prng_read_seedfile(void) {
|
||||
int fd;
|
||||
char seed[1024];
|
||||
char filename[1024];
|
||||
struct passwd *pw;
|
||||
|
||||
pw = getpwuid(getuid());
|
||||
if (pw == NULL)
|
||||
fatal("Couldn't get password entry for current user (%i): %s",
|
||||
getuid(), strerror(errno));
|
||||
|
||||
snprintf(filename, sizeof(filename), "%.512s/%s", pw->pw_dir,
|
||||
SSH_PRNG_SEED_FILE);
|
||||
|
||||
debug("loading PRNG seed from file %.100s", filename);
|
||||
|
||||
if (!prng_check_seedfile(filename)) {
|
||||
verbose("Random seed file not found or not valid, ignoring.");
|
||||
return;
|
||||
}
|
||||
|
||||
/* open the file and read in the seed */
|
||||
fd = open(filename, O_RDONLY);
|
||||
if (fd == -1)
|
||||
fatal("could not open PRNG seedfile %.100s (%.100s)", filename,
|
||||
strerror(errno));
|
||||
|
||||
if (atomicio(read, fd, &seed, sizeof(seed)) != sizeof(seed)) {
|
||||
verbose("invalid or short read from PRNG seedfile %.100s - ignoring",
|
||||
filename);
|
||||
memset(seed, '\0', sizeof(seed));
|
||||
}
|
||||
close(fd);
|
||||
|
||||
/* stir in the seed, with estimated entropy zero */
|
||||
RAND_add(&seed, sizeof(seed), 0.0);
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* entropy command initialisation functions
|
||||
*/
|
||||
int
|
||||
prng_read_commands(char *cmdfilename)
|
||||
{
|
||||
FILE *f;
|
||||
char *cp;
|
||||
char line[1024];
|
||||
char cmd[1024];
|
||||
char path[256];
|
||||
int linenum;
|
||||
int num_cmds = 64;
|
||||
int cur_cmd = 0;
|
||||
double est;
|
||||
entropy_source_t *entcmd;
|
||||
|
||||
f = fopen(cmdfilename, "r");
|
||||
if (!f) {
|
||||
fatal("couldn't read entropy commands file %.100s: %.100s",
|
||||
cmdfilename, strerror(errno));
|
||||
}
|
||||
|
||||
entcmd = (entropy_source_t *)xmalloc(num_cmds * sizeof(entropy_source_t));
|
||||
memset(entcmd, '\0', num_cmds * sizeof(entropy_source_t));
|
||||
|
||||
/* Read in file */
|
||||
linenum = 0;
|
||||
while (fgets(line, sizeof(line), f)) {
|
||||
int arg;
|
||||
char *argv;
|
||||
|
||||
linenum++;
|
||||
|
||||
/* skip leading whitespace, test for blank line or comment */
|
||||
cp = line + strspn(line, WHITESPACE);
|
||||
if ((*cp == 0) || (*cp == '#'))
|
||||
continue; /* done with this line */
|
||||
|
||||
/* First non-whitespace char should be double quote delimiting */
|
||||
/* commandline */
|
||||
if (*cp != '"') {
|
||||
error("bad entropy command, %.100s line %d", cmdfilename,
|
||||
linenum);
|
||||
continue;
|
||||
}
|
||||
|
||||
/* first token, command args (incl. argv[0]) in double quotes */
|
||||
cp = strtok(cp, "\"");
|
||||
if (cp == NULL) {
|
||||
error("missing or bad command string, %.100s line %d -- ignored",
|
||||
cmdfilename, linenum);
|
||||
continue;
|
||||
}
|
||||
strlcpy(cmd, cp, sizeof(cmd));
|
||||
|
||||
/* second token, full command path */
|
||||
if ((cp = strtok(NULL, WHITESPACE)) == NULL) {
|
||||
error("missing command path, %.100s line %d -- ignored",
|
||||
cmdfilename, linenum);
|
||||
continue;
|
||||
}
|
||||
|
||||
/* did configure mark this as dead? */
|
||||
if (strncmp("undef", cp, 5) == 0)
|
||||
continue;
|
||||
|
||||
strlcpy(path, cp, sizeof(path));
|
||||
|
||||
/* third token, entropy rate estimate for this command */
|
||||
if ((cp = strtok(NULL, WHITESPACE)) == NULL) {
|
||||
error("missing entropy estimate, %.100s line %d -- ignored",
|
||||
cmdfilename, linenum);
|
||||
continue;
|
||||
}
|
||||
est = strtod(cp, &argv);
|
||||
|
||||
/* end of line */
|
||||
if ((cp = strtok(NULL, WHITESPACE)) != NULL) {
|
||||
error("garbage at end of line %d in %.100s -- ignored", linenum,
|
||||
cmdfilename);
|
||||
continue;
|
||||
}
|
||||
|
||||
/* save the command for debug messages */
|
||||
entcmd[cur_cmd].cmdstring = xstrdup(cmd);
|
||||
|
||||
/* split the command args */
|
||||
cp = strtok(cmd, WHITESPACE);
|
||||
arg = 0;
|
||||
argv = NULL;
|
||||
do {
|
||||
char *s = (char*)xmalloc(strlen(cp) + 1);
|
||||
strncpy(s, cp, strlen(cp) + 1);
|
||||
entcmd[cur_cmd].args[arg] = s;
|
||||
arg++;
|
||||
} while ((arg < 5) && (cp = strtok(NULL, WHITESPACE)));
|
||||
|
||||
if (strtok(NULL, WHITESPACE))
|
||||
error("ignored extra command elements (max 5), %.100s line %d",
|
||||
cmdfilename, linenum);
|
||||
|
||||
/* Copy the command path and rate estimate */
|
||||
entcmd[cur_cmd].path = xstrdup(path);
|
||||
entcmd[cur_cmd].rate = est;
|
||||
|
||||
/* Initialise other values */
|
||||
entcmd[cur_cmd].sticky_badness = 1;
|
||||
|
||||
cur_cmd++;
|
||||
|
||||
/* If we've filled the array, reallocate it twice the size */
|
||||
/* Do this now because even if this we're on the last command,
|
||||
we need another slot to mark the last entry */
|
||||
if (cur_cmd == num_cmds) {
|
||||
num_cmds *= 2;
|
||||
entcmd = xrealloc(entcmd, num_cmds * sizeof(entropy_source_t));
|
||||
}
|
||||
}
|
||||
|
||||
/* zero the last entry */
|
||||
memset(&entcmd[cur_cmd], '\0', sizeof(entropy_source_t));
|
||||
|
||||
/* trim to size */
|
||||
entropy_sources = xrealloc(entcmd, (cur_cmd+1) * sizeof(entropy_source_t));
|
||||
|
||||
debug("Loaded %d entropy commands from %.100s", cur_cmd, cmdfilename);
|
||||
|
||||
return (cur_cmd >= MIN_ENTROPY_SOURCES);
|
||||
}
|
||||
|
||||
static void
|
||||
seed_openssl_rng(void)
|
||||
{
|
||||
/* Read in collection commands */
|
||||
if (!prng_read_commands(SSH_PRNG_COMMAND_FILE))
|
||||
fatal("PRNG initialisation failed -- exiting.");
|
||||
|
||||
prng_read_seedfile();
|
||||
|
||||
debug("Seeded RNG with %i bytes from programs",
|
||||
(int)stir_from_programs());
|
||||
debug("Seeded RNG with %i bytes from system calls",
|
||||
(int)stir_from_system());
|
||||
|
||||
prng_write_seedfile();
|
||||
}
|
||||
|
||||
#endif /* USE_PRNGD */
|
||||
|
||||
int
|
||||
main(int argc, char **argv)
|
||||
{
|
||||
unsigned char buf[48];
|
||||
int ret;
|
||||
|
||||
/* XXX: need some debugging mode */
|
||||
log_init(argv[0], SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_USER, 1);
|
||||
|
||||
seed_openssl_rng();
|
||||
|
||||
if (!RAND_status())
|
||||
fatal("Not enough entropy in RNG");
|
||||
|
||||
RAND_bytes(buf, sizeof(buf));
|
||||
|
||||
ret = atomicio(write, STDOUT_FILENO, buf, sizeof(buf));
|
||||
|
||||
memset(buf, '\0', sizeof(buf));
|
||||
|
||||
return ret == sizeof(buf) ? 0 : 1;
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user