diff --git a/entropy.c b/entropy.c index 1e9d52a..d24e724 100644 --- a/entropy.c +++ b/entropy.c @@ -227,6 +227,9 @@ seed_rng(void) memset(buf, '\0', sizeof(buf)); #endif /* OPENSSL_PRNG_ONLY */ +#ifdef __linux__ + linux_seed(); +#endif /* __linux__ */ if (RAND_status() != 1) fatal("PRNG is not seeded"); } diff --git a/openbsd-compat/Makefile.in b/openbsd-compat/Makefile.in index 843225d..041bbab 100644 --- a/openbsd-compat/Makefile.in +++ b/openbsd-compat/Makefile.in @@ -20,7 +20,7 @@ OPENBSD=base64.o basename.o bcrypt_pbkdf.o bindresvport.o blowfish.o daemon.o di COMPAT=arc4random.o bsd-asprintf.o bsd-closefrom.o bsd-cray.o bsd-cygwin_util.o bsd-getpeereid.o getrrsetbyname-ldns.o bsd-misc.o bsd-nextstep.o bsd-openpty.o bsd-poll.o bsd-setres_id.o bsd-snprintf.o bsd-statvfs.o bsd-waitpid.o fake-rfc2553.o openssl-compat.o xmmap.o xcrypt.o kludge-fd_set.o -PORTS=port-aix.o port-irix.o port-linux.o port-linux-sshd.o port-solaris.o port-tun.o port-uw.o +PORTS=port-aix.o port-irix.o port-linux.o port-linux-sshd.o port-linux-prng.o port-solaris.o port-tun.o port-uw.o .c.o: $(CC) $(CFLAGS) $(CPPFLAGS) -c $< diff --git a/openbsd-compat/port-linux-prng.c b/openbsd-compat/port-linux-prng.c new file mode 100644 index 0000000..da84bf2 --- /dev/null +++ b/openbsd-compat/port-linux-prng.c @@ -0,0 +1,59 @@ +/* $Id: port-linux.c,v 1.11.4.2 2011/02/04 00:43:08 djm Exp $ */ + +/* + * Copyright (c) 2011 Jan F. Chadima + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +/* + * Linux-specific portability code - prng support + */ + +#include "includes.h" + +#include +#include +#include +#include +#include + +#include "log.h" +#include "xmalloc.h" +#include "misc.h" /* servconf.h needs misc.h for struct ForwardOptions */ +#include "servconf.h" +#include "port-linux.h" +#include "key.h" +#include "hostfile.h" +#include "auth.h" + +void +linux_seed(void) +{ + char *env = getenv("SSH_USE_STRONG_RNG"); + char *random = "/dev/random"; + size_t len, ienv, randlen = 14; + + if (!env || !strcmp(env, "0")) + random = "/dev/urandom"; + else if ((ienv = atoi(env)) > randlen) + randlen = ienv; + + errno = 0; + if ((len = RAND_load_file(random, randlen)) != randlen) { + if (errno) + fatal ("cannot read from %s, %s", random, strerror(errno)); + else + fatal ("EOF reading %s", random); + } +} diff --git a/ssh-add.0 b/ssh-add.0 index f16165a..17d22cf 100644 --- a/ssh-add.0 +++ b/ssh-add.0 @@ -82,6 +82,16 @@ ENVIRONMENT Identifies the path of a UNIX-domain socket used to communicate with the agent. + SSH_USE_STRONG_RNG + The reseeding of the OpenSSL random generator is usually done + from /dev/urandom. If the SSH_USE_STRONG_RNG environment vari- + able is set to value other than 0 the OpenSSL random generator is + reseeded from /dev/random. The number of bytes read is defined + by the SSH_USE_STRONG_RNG value. Minimum is 14 bytes. This set- + ting is not recommended on the computers without the hardware + random generator because insufficient entropy causes the connec- + tion to be blocked until enough entropy is available. + FILES ~/.ssh/identity Contains the protocol version 1 RSA authentication identity of diff --git a/ssh-add.1 b/ssh-add.1 index 04d1840..db883a4 100644 --- a/ssh-add.1 +++ b/ssh-add.1 @@ -170,6 +170,20 @@ to make this work.) Identifies the path of a .Ux Ns -domain socket used to communicate with the agent. +.It Ev SSH_USE_STRONG_RNG +The reseeding of the OpenSSL random generator is usually done from +.Cm /dev/urandom . +If the +.Cm SSH_USE_STRONG_RNG +environment variable is set to value other than +.Cm 0 +the OpenSSL random generator is reseeded from +.Cm /dev/random . +The number of bytes read is defined by the SSH_USE_STRONG_RNG value. +Minimum is 14 bytes. +This setting is not recommended on the computers without the hardware +random generator because insufficient entropy causes the connection to +be blocked until enough entropy is available. .El .Sh FILES .Bl -tag -width Ds diff --git a/ssh-agent.1 b/ssh-agent.1 index d7e791b..7332f0d 100644 --- a/ssh-agent.1 +++ b/ssh-agent.1 @@ -189,6 +189,24 @@ sockets used to contain the connection to the authentication agent. These sockets should only be readable by the owner. The sockets should get automatically removed when the agent exits. .El +.Sh ENVIRONMENT +.Bl -tag -width Ds -compact +.Pp +.It Pa SSH_USE_STRONG_RNG +The reseeding of the OpenSSL random generator is usually done from +.Cm /dev/urandom . +If the +.Cm SSH_USE_STRONG_RNG +environment variable is set to value other than +.Cm 0 +the OpenSSL random generator is reseeded from +.Cm /dev/random . +The number of bytes read is defined by the SSH_USE_STRONG_RNG value. +Minimum is 14 bytes. +This setting is not recommended on the computers without the hardware +random generator because insufficient entropy causes the connection to +be blocked until enough entropy is available. +.El .Sh SEE ALSO .Xr ssh 1 , .Xr ssh-add 1 , diff --git a/ssh-keygen.1 b/ssh-keygen.1 index 276dacc..a09d9b1 100644 --- a/ssh-keygen.1 +++ b/ssh-keygen.1 @@ -841,6 +841,24 @@ Contains Diffie-Hellman groups used for DH-GEX. The file format is described in .Xr moduli 5 . .El +.Sh ENVIRONMENT +.Bl -tag -width Ds -compact +.Pp +.It Pa SSH_USE_STRONG_RNG +The reseeding of the OpenSSL random generator is usually done from +.Cm /dev/urandom . +If the +.Cm SSH_USE_STRONG_RNG +environment variable is set to value other than +.Cm 0 +the OpenSSL random generator is reseeded from +.Cm /dev/random . +The number of bytes read is defined by the SSH_USE_STRONG_RNG value. +Minimum is 14 bytes. +This setting is not recommended on the computers without the hardware +random generator because insufficient entropy causes the connection to +be blocked until enough entropy is available. +.El .Sh SEE ALSO .Xr ssh 1 , .Xr ssh-add 1 , diff --git a/ssh-keysign.8 b/ssh-keysign.8 index 69d0829..02d79f8 100644 --- a/ssh-keysign.8 +++ b/ssh-keysign.8 @@ -80,6 +80,24 @@ must be set-uid root if host-based authentication is used. If these files exist they are assumed to contain public certificate information corresponding with the private keys above. .El +.Sh ENVIRONMENT +.Bl -tag -width Ds -compact +.Pp +.It Pa SSH_USE_STRONG_RNG +The reseeding of the OpenSSL random generator is usually done from +.Cm /dev/urandom . +If the +.Cm SSH_USE_STRONG_RNG +environment variable is set to value other than +.Cm 0 +the OpenSSL random generator is reseeded from +.Cm /dev/random . +The number of bytes read is defined by the SSH_USE_STRONG_RNG value. +Minimum is 14 bytes. +This setting is not recommended on the computers without the hardware +random generator because insufficient entropy causes the connection to +be blocked until enough entropy is available. +.El .Sh SEE ALSO .Xr ssh 1 , .Xr ssh-keygen 1 , diff --git a/ssh.1 b/ssh.1 index 4a476c2..410a04a 100644 --- a/ssh.1 +++ b/ssh.1 @@ -1299,6 +1299,23 @@ For more information, see the .Cm PermitUserEnvironment option in .Xr sshd_config 5 . +.Sh ENVIRONMENT +.Bl -tag -width Ds -compact +.It Ev SSH_USE_STRONG_RNG +The reseeding of the OpenSSL random generator is usually done from +.Cm /dev/urandom . +If the +.Cm SSH_USE_STRONG_RNG +environment variable is set to value other than +.Cm 0 +the OpenSSL random generator is reseeded from +.Cm /dev/random . +The number of bytes read is defined by the SSH_USE_STRONG_RNG value. +Minimum is 14 bytes. +This setting is not recommended on the computers without the hardware +random generator because insufficient entropy causes the connection to +be blocked until enough entropy is available. +.El .Sh FILES .Bl -tag -width Ds -compact .It Pa ~/.rhosts diff --git a/sshd.8 b/sshd.8 index cb866b5..adcaaf9 100644 --- a/sshd.8 +++ b/sshd.8 @@ -945,6 +945,24 @@ concurrently for different ports, this contains the process ID of the one started last). The content of this file is not sensitive; it can be world-readable. .El +.Sh ENVIRONMENT +.Bl -tag -width Ds -compact +.Pp +.It Pa SSH_USE_STRONG_RNG +The reseeding of the OpenSSL random generator is usually done from +.Cm /dev/urandom . +If the +.Cm SSH_USE_STRONG_RNG +environment variable is set to value other than +.Cm 0 +the OpenSSL random generator is reseeded from +.Cm /dev/random . +The number of bytes read is defined by the SSH_USE_STRONG_RNG value. +Minimum is 14 bytes. +This setting is not recommended on the computers without the hardware +random generator because insufficient entropy causes the connection to +be blocked until enough entropy is available. +.El .Sh IPV6 IPv6 address can be used everywhere where IPv4 address. In all entries must be the IPv6 address enclosed in square brackets. Note: The square brackets are metacharacters for the shell and must be escaped in shell. .Sh SEE ALSO