freebsd-dev/crypto/openssh/myproposal.h
Ed Maste 952d18a214 ssh: Remove AES-CBC ciphers from default server and client lists
A base system OpenSSH update in 2016 or so removed a number of ciphers
from the default lists offered by the server/client, due to known
weaknesses.  This caused POLA issues for some users and prompted
PR207679; the ciphers were restored to the default lists in r296634.

When upstream removed these ciphers from the default server list, they
moved them to the client-only default list.  They were subsequently
removed from the client default, in OpenSSH 7.9p1.

The change has persisted long enough.  Remove these extra ciphers from
both the server and client default lists, in advance of FreeBSD 13.

Reviewed by:	markm, rgrimes
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D25833
2020-07-28 00:24:12 +00:00

210 lines
5.6 KiB
C

/* $OpenBSD: myproposal.h,v 1.57 2018/09/12 01:34:02 djm Exp $ */
/*
* Copyright (c) 2000 Markus Friedl. 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 <openssl/opensslv.h>
/* conditional algorithm support */
#ifdef OPENSSL_HAS_ECC
#ifdef OPENSSL_HAS_NISTP521
# define KEX_ECDH_METHODS \
"ecdh-sha2-nistp256," \
"ecdh-sha2-nistp384," \
"ecdh-sha2-nistp521,"
# define HOSTKEY_ECDSA_CERT_METHODS \
"ecdsa-sha2-nistp256-cert-v01@openssh.com," \
"ecdsa-sha2-nistp384-cert-v01@openssh.com," \
"ecdsa-sha2-nistp521-cert-v01@openssh.com,"
# define HOSTKEY_ECDSA_METHODS \
"ecdsa-sha2-nistp256," \
"ecdsa-sha2-nistp384," \
"ecdsa-sha2-nistp521,"
#else
# define KEX_ECDH_METHODS \
"ecdh-sha2-nistp256," \
"ecdh-sha2-nistp384,"
# define HOSTKEY_ECDSA_CERT_METHODS \
"ecdsa-sha2-nistp256-cert-v01@openssh.com," \
"ecdsa-sha2-nistp384-cert-v01@openssh.com,"
# define HOSTKEY_ECDSA_METHODS \
"ecdsa-sha2-nistp256," \
"ecdsa-sha2-nistp384,"
#endif
#else
# define KEX_ECDH_METHODS
# define HOSTKEY_ECDSA_CERT_METHODS
# define HOSTKEY_ECDSA_METHODS
#endif
#ifdef OPENSSL_HAVE_EVPGCM
# define AESGCM_CIPHER_MODES \
",aes128-gcm@openssh.com,aes256-gcm@openssh.com"
#else
# define AESGCM_CIPHER_MODES
#endif
#ifdef HAVE_EVP_SHA256
# define KEX_SHA2_METHODS \
"diffie-hellman-group-exchange-sha256," \
"diffie-hellman-group16-sha512," \
"diffie-hellman-group18-sha512,"
# define KEX_SHA2_GROUP14 \
"diffie-hellman-group14-sha256,"
#define SHA2_HMAC_MODES \
"hmac-sha2-256," \
"hmac-sha2-512,"
#else
# define KEX_SHA2_METHODS
# define KEX_SHA2_GROUP14
# define SHA2_HMAC_MODES
#endif
#ifdef WITH_OPENSSL
# ifdef HAVE_EVP_SHA256
# define KEX_CURVE25519_METHODS \
"curve25519-sha256," \
"curve25519-sha256@libssh.org,"
# else
# define KEX_CURVE25519_METHODS ""
# endif
#define KEX_COMMON_KEX \
KEX_CURVE25519_METHODS \
KEX_ECDH_METHODS \
KEX_SHA2_METHODS
#define KEX_SERVER_KEX KEX_COMMON_KEX \
KEX_SHA2_GROUP14 \
"diffie-hellman-group14-sha1" \
#define KEX_CLIENT_KEX KEX_COMMON_KEX \
"diffie-hellman-group-exchange-sha1," \
KEX_SHA2_GROUP14 \
"diffie-hellman-group14-sha1"
#define KEX_DEFAULT_PK_ALG \
HOSTKEY_ECDSA_CERT_METHODS \
"ssh-ed25519-cert-v01@openssh.com," \
"rsa-sha2-512-cert-v01@openssh.com," \
"rsa-sha2-256-cert-v01@openssh.com," \
"ssh-rsa-cert-v01@openssh.com," \
HOSTKEY_ECDSA_METHODS \
"ssh-ed25519," \
"rsa-sha2-512," \
"rsa-sha2-256," \
"ssh-rsa"
/* the actual algorithms */
#define KEX_SERVER_ENCRYPT \
"chacha20-poly1305@openssh.com," \
"aes128-ctr,aes192-ctr,aes256-ctr" \
AESGCM_CIPHER_MODES
#define KEX_CLIENT_ENCRYPT KEX_SERVER_ENCRYPT
#define KEX_SERVER_MAC \
"umac-64-etm@openssh.com," \
"umac-128-etm@openssh.com," \
"hmac-sha2-256-etm@openssh.com," \
"hmac-sha2-512-etm@openssh.com," \
"hmac-sha1-etm@openssh.com," \
"umac-64@openssh.com," \
"umac-128@openssh.com," \
"hmac-sha2-256," \
"hmac-sha2-512," \
"hmac-sha1"
#define KEX_CLIENT_MAC KEX_SERVER_MAC
/* Not a KEX value, but here so all the algorithm defaults are together */
#define SSH_ALLOWED_CA_SIGALGS \
"ecdsa-sha2-nistp256," \
"ecdsa-sha2-nistp384," \
"ecdsa-sha2-nistp521," \
"ssh-ed25519," \
"rsa-sha2-512," \
"rsa-sha2-256," \
"ssh-rsa"
#else /* WITH_OPENSSL */
#define KEX_SERVER_KEX \
"curve25519-sha256," \
"curve25519-sha256@libssh.org"
#define KEX_DEFAULT_PK_ALG \
"ssh-ed25519-cert-v01@openssh.com," \
"ssh-ed25519"
#define KEX_SERVER_ENCRYPT \
"chacha20-poly1305@openssh.com," \
"aes128-ctr,aes192-ctr,aes256-ctr"
#define KEX_SERVER_MAC \
"umac-64-etm@openssh.com," \
"umac-128-etm@openssh.com," \
"hmac-sha2-256-etm@openssh.com," \
"hmac-sha2-512-etm@openssh.com," \
"hmac-sha1-etm@openssh.com," \
"umac-64@openssh.com," \
"umac-128@openssh.com," \
"hmac-sha2-256," \
"hmac-sha2-512," \
"hmac-sha1"
#define KEX_CLIENT_KEX KEX_SERVER_KEX
#define KEX_CLIENT_ENCRYPT KEX_SERVER_ENCRYPT
#define KEX_CLIENT_MAC KEX_SERVER_MAC
#define SSH_ALLOWED_CA_SIGALGS "ssh-ed25519"
#endif /* WITH_OPENSSL */
#define KEX_DEFAULT_COMP "none,zlib@openssh.com"
#define KEX_DEFAULT_LANG ""
#define KEX_CLIENT \
KEX_CLIENT_KEX, \
KEX_DEFAULT_PK_ALG, \
KEX_CLIENT_ENCRYPT, \
KEX_CLIENT_ENCRYPT, \
KEX_CLIENT_MAC, \
KEX_CLIENT_MAC, \
KEX_DEFAULT_COMP, \
KEX_DEFAULT_COMP, \
KEX_DEFAULT_LANG, \
KEX_DEFAULT_LANG
#define KEX_SERVER \
KEX_SERVER_KEX, \
KEX_DEFAULT_PK_ALG, \
KEX_SERVER_ENCRYPT, \
KEX_SERVER_ENCRYPT, \
KEX_SERVER_MAC, \
KEX_SERVER_MAC, \
KEX_DEFAULT_COMP, \
KEX_DEFAULT_COMP, \
KEX_DEFAULT_LANG, \
KEX_DEFAULT_LANG