[arch-commits] Commit in openssh/trunk (PKGBUILD curve25519pad.patch)

Gaetan Bisson bisson at nymeria.archlinux.org
Sun Apr 20 19:40:17 UTC 2014


    Date: Sunday, April 20, 2014 @ 21:40:17
  Author: bisson
Revision: 211579

tiny upstream fix

Added:
  openssh/trunk/curve25519pad.patch
Modified:
  openssh/trunk/PKGBUILD

---------------------+
 PKGBUILD            |    9 ++
 curve25519pad.patch |  171 ++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 179 insertions(+), 1 deletion(-)

Modified: PKGBUILD
===================================================================
--- PKGBUILD	2014-04-20 16:51:44 UTC (rev 211578)
+++ PKGBUILD	2014-04-20 19:40:17 UTC (rev 211579)
@@ -5,7 +5,7 @@
 
 pkgname=openssh
 pkgver=6.6p1
-pkgrel=1
+pkgrel=2
 pkgdesc='Free version of the SSH connectivity tools'
 url='http://www.openssh.org/portable.html'
 license=('custom:BSD')
@@ -15,6 +15,7 @@
 optdepends=('xorg-xauth: X11 forwarding'
             'x11-ssh-askpass: input passphrase in X')
 source=("ftp://ftp.openbsd.org/pub/OpenBSD/OpenSSH/portable/${pkgname}-${pkgver}.tar.gz"{,.asc}
+        'curve25519pad.patch'
         'sshdgenkeys.service'
         'sshd at .service'
         'sshd.service'
@@ -21,6 +22,7 @@
         'sshd.socket'
         'sshd.pam')
 sha1sums=('b850fd1af704942d9b3c2eff7ef6b3a59b6a6b6e' 'SKIP'
+          '13b74b57b3d9b9a256eeb44b4fca29a8f27aa7ad'
           'cc1ceec606c98c7407e7ac21ade23aed81e31405'
           '6a0ff3305692cf83aca96e10f3bb51e1c26fccda'
           'ec49c6beba923e201505f5669cea48cad29014db'
@@ -31,6 +33,11 @@
 
 install=install
 
+prepare() {
+	cd "${srcdir}/${pkgname}-${pkgver}"
+	patch -p0 -i ../curve25519pad.patch
+}
+
 build() {
 	cd "${srcdir}/${pkgname}-${pkgver}"
 

Added: curve25519pad.patch
===================================================================
--- curve25519pad.patch	                        (rev 0)
+++ curve25519pad.patch	2014-04-20 19:40:17 UTC (rev 211579)
@@ -0,0 +1,171 @@
+Hi,
+
+So I screwed up when writing the support for the curve25519 KEX method
+that doesn't depend on OpenSSL's BIGNUM type - a bug in my code left
+leading zero bytes where they should have been skipped. The impact of
+this is that OpenSSH 6.5 and 6.6 will fail during key exchange with a
+peer that implements curve25519-sha256 at libssh.org properly about 0.2%
+of the time (one in every 512ish connections).
+
+We've fixed this for OpenSSH 6.7 by avoiding the curve25519-sha256
+key exchange for previous versions, but I'd recommend distributors
+of OpenSSH apply this patch so the affected code doesn't become
+too entrenched in LTS releases.
+
+The patch fixes the bug and makes OpenSSH identify itself as 6.6.1 so as
+to distinguish itself from the incorrect versions so the compatibility
+code to disable the affected KEX isn't activated.
+
+I've committed this on the 6.6 branch too.
+
+Apologies for the hassle.
+
+-d
+
+Index: version.h
+===================================================================
+RCS file: /var/cvs/openssh/version.h,v
+retrieving revision 1.82
+diff -u -p -r1.82 version.h
+--- version.h	27 Feb 2014 23:01:54 -0000	1.82
++++ version.h	20 Apr 2014 03:35:15 -0000
+@@ -1,6 +1,6 @@
+ /* $OpenBSD: version.h,v 1.70 2014/02/27 22:57:40 djm Exp $ */
+ 
+-#define SSH_VERSION	"OpenSSH_6.6"
++#define SSH_VERSION	"OpenSSH_6.6.1"
+ 
+ #define SSH_PORTABLE	"p1"
+ #define SSH_RELEASE	SSH_VERSION SSH_PORTABLE
+Index: compat.c
+===================================================================
+RCS file: /var/cvs/openssh/compat.c,v
+retrieving revision 1.82
+retrieving revision 1.85
+diff -u -p -r1.82 -r1.85
+--- compat.c	31 Dec 2013 01:25:41 -0000	1.82
++++ compat.c	20 Apr 2014 03:33:59 -0000	1.85
+@@ -95,6 +95,9 @@ compat_datafellows(const char *version)
+ 		{ "Sun_SSH_1.0*",	SSH_BUG_NOREKEY|SSH_BUG_EXTEOF},
+ 		{ "OpenSSH_4*",		0 },
+ 		{ "OpenSSH_5*",		SSH_NEW_OPENSSH|SSH_BUG_DYNAMIC_RPORT},
++		{ "OpenSSH_6.6.1*",	SSH_NEW_OPENSSH},
++		{ "OpenSSH_6.5*,"
++		  "OpenSSH_6.6*",	SSH_NEW_OPENSSH|SSH_BUG_CURVE25519PAD},
+ 		{ "OpenSSH*",		SSH_NEW_OPENSSH },
+ 		{ "*MindTerm*",		0 },
+ 		{ "2.1.0*",		SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
+@@ -251,7 +254,6 @@ compat_cipher_proposal(char *cipher_prop
+ 	return cipher_prop;
+ }
+ 
+-
+ char *
+ compat_pkalg_proposal(char *pkalg_prop)
+ {
+@@ -263,5 +265,18 @@ compat_pkalg_proposal(char *pkalg_prop)
+ 	if (*pkalg_prop == '\0')
+ 		fatal("No supported PK algorithms found");
+ 	return pkalg_prop;
++}
++
++char *
++compat_kex_proposal(char *kex_prop)
++{
++	if (!(datafellows & SSH_BUG_CURVE25519PAD))
++		return kex_prop;
++	debug2("%s: original KEX proposal: %s", __func__, kex_prop);
++	kex_prop = filter_proposal(kex_prop, "curve25519-sha256 at libssh.org");
++	debug2("%s: compat KEX proposal: %s", __func__, kex_prop);
++	if (*kex_prop == '\0')
++		fatal("No supported key exchange algorithms found");
++	return kex_prop;
+ }
+ 
+Index: compat.h
+===================================================================
+RCS file: /var/cvs/openssh/compat.h,v
+retrieving revision 1.42
+retrieving revision 1.43
+diff -u -p -r1.42 -r1.43
+--- compat.h	31 Dec 2013 01:25:41 -0000	1.42
++++ compat.h	20 Apr 2014 03:25:31 -0000	1.43
+@@ -59,6 +59,7 @@
+ #define SSH_BUG_RFWD_ADDR	0x02000000
+ #define SSH_NEW_OPENSSH		0x04000000
+ #define SSH_BUG_DYNAMIC_RPORT	0x08000000
++#define SSH_BUG_CURVE25519PAD	0x10000000
+ 
+ void     enable_compat13(void);
+ void     enable_compat20(void);
+@@ -66,6 +67,7 @@ void     compat_datafellows(const char *
+ int	 proto_spec(const char *);
+ char	*compat_cipher_proposal(char *);
+ char	*compat_pkalg_proposal(char *);
++char	*compat_kex_proposal(char *);
+ 
+ extern int compat13;
+ extern int compat20;
+Index: sshd.c
+===================================================================
+RCS file: /var/cvs/openssh/sshd.c,v
+retrieving revision 1.448
+retrieving revision 1.453
+diff -u -p -r1.448 -r1.453
+--- sshd.c	26 Feb 2014 23:20:08 -0000	1.448
++++ sshd.c	20 Apr 2014 03:28:41 -0000	1.453
+@@ -2462,6 +2438,9 @@ do_ssh2_kex(void)
+ 	if (options.kex_algorithms != NULL)
+ 		myproposal[PROPOSAL_KEX_ALGS] = options.kex_algorithms;
+ 
++	myproposal[PROPOSAL_KEX_ALGS] = compat_kex_proposal(
++	    myproposal[PROPOSAL_KEX_ALGS]);
++
+ 	if (options.rekey_limit || options.rekey_interval)
+ 		packet_set_rekey_limits((u_int32_t)options.rekey_limit,
+ 		    (time_t)options.rekey_interval);
+Index: sshconnect2.c
+===================================================================
+RCS file: /var/cvs/openssh/sshconnect2.c,v
+retrieving revision 1.197
+retrieving revision 1.199
+diff -u -p -r1.197 -r1.199
+--- sshconnect2.c	4 Feb 2014 00:20:16 -0000	1.197
++++ sshconnect2.c	20 Apr 2014 03:25:31 -0000	1.199
+@@ -195,6 +196,8 @@ ssh_kex2(char *host, struct sockaddr *ho
+ 	}
+ 	if (options.kex_algorithms != NULL)
+ 		myproposal[PROPOSAL_KEX_ALGS] = options.kex_algorithms;
++	myproposal[PROPOSAL_KEX_ALGS] = compat_kex_proposal(
++	    myproposal[PROPOSAL_KEX_ALGS]);
+ 
+ 	if (options.rekey_limit || options.rekey_interval)
+ 		packet_set_rekey_limits((u_int32_t)options.rekey_limit,
+Index: bufaux.c
+===================================================================
+RCS file: /var/cvs/openssh/bufaux.c,v
+retrieving revision 1.62
+retrieving revision 1.63
+diff -u -p -r1.62 -r1.63
+--- bufaux.c	4 Feb 2014 00:20:15 -0000	1.62
++++ bufaux.c	20 Apr 2014 03:24:50 -0000	1.63
+@@ -1,4 +1,4 @@
+-/* $OpenBSD: bufaux.c,v 1.56 2014/02/02 03:44:31 djm Exp $ */
++/* $OpenBSD: bufaux.c,v 1.57 2014/04/16 23:22:45 djm Exp $ */
+ /*
+  * Author: Tatu Ylonen <ylo at cs.hut.fi>
+  * Copyright (c) 1995 Tatu Ylonen <ylo at cs.hut.fi>, Espoo, Finland
+@@ -372,6 +372,9 @@ buffer_put_bignum2_from_string(Buffer *b
+ 
+ 	if (l > 8 * 1024)
+ 		fatal("%s: length %u too long", __func__, l);
++	/* Skip leading zero bytes */
++	for (; l > 0 && *s == 0; l--, s++)
++		;
+ 	p = buf = xmalloc(l + 1);
+ 	/*
+ 	 * If most significant bit is set then prepend a zero byte to
+_______________________________________________
+openssh-unix-dev mailing list
+openssh-unix-dev at mindrot.org
+https://lists.mindrot.org/mailman/listinfo/openssh-unix-dev
\ No newline at end of file




More information about the arch-commits mailing list