upstream: allow security keys to act as host keys as well as user

keys.

Previously we didn't do this because we didn't want to expose
the attack surface presented by USB and FIDO protocol handling,
but now that this is insulated behind ssh-sk-helper there is
less risk.

ok markus@

OpenBSD-Commit-ID: 77b068dd133b8d87e0f010987bd5131e640ee64c

1 files changed, 11 insertions, 29 deletions

diff --git a/myproposal.h b/myproposal.h
index b393db8b0..6688c3066 100644
--- a/myproposal.h
+++ b/myproposal.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: myproposal.h,v 1.62 2019/12/10 22:43:19 djm Exp $ */
+/* $OpenBSD: myproposal.h,v 1.63 2019/12/15 18:57:30 djm Exp $ */
 
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
@@ -39,32 +39,30 @@
 #  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,"
+        "ecdsa-sha2-nistp521-cert-v01@openssh.com," \
+        "sk-ecdsa-sha2-nistp256-cert-v01@openssh.com,"
 #  define HOSTKEY_ECDSA_METHODS \
         "ecdsa-sha2-nistp256," \
         "ecdsa-sha2-nistp384," \
-        "ecdsa-sha2-nistp521,"
+        "ecdsa-sha2-nistp521," \
+        "sk-ecdsa-sha2-nistp256@openssh.com,"
 # else /* OPENSSL_HAS_NISTP521 */
 #  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,"
+        "ecdsa-sha2-nistp384-cert-v01@openssh.com," \
+        "sk-ecdsa-sha2-nistp256-cert-v01@openssh.com,"
 #  define HOSTKEY_ECDSA_METHODS \
         "ecdsa-sha2-nistp256," \
-        "ecdsa-sha2-nistp384,"
-# endif /* OPENSSL_HAS_NISTP521 */
-# define USERKEY_ECDSA_SK_CERT_METHODS \
-        "sk-ecdsa-sha2-nistp256-cert-v01@openssh.com,"
-# define USERKEY_ECDSA_SK_METHODS \
+        "ecdsa-sha2-nistp384," \
         "sk-ecdsa-sha2-nistp256@openssh.com,"
+# endif /* OPENSSL_HAS_NISTP521 */
 #else /* OPENSSL_HAS_ECC */
 # define KEX_ECDH_METHODS
 # define HOSTKEY_ECDSA_CERT_METHODS
 # define HOSTKEY_ECDSA_METHODS
-# define USERKEY_ECDSA_SK_CERT_METHODS
-# define USERKEY_ECDSA_SK_METHODS
 #endif /* OPENSSL_HAS_ECC */
 
 #ifdef OPENSSL_HAVE_EVPGCM
@@ -110,11 +108,13 @@
 #define KEX_DEFAULT_PK_ALG      \
         HOSTKEY_ECDSA_CERT_METHODS \
         "ssh-ed25519-cert-v01@openssh.com," \
+        "sk-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," \
+        "sk-ssh-ed25519@openssh.com," \
         "rsa-sha2-512," \
         "rsa-sha2-256," \
         "ssh-rsa"
@@ -145,29 +145,12 @@
 /* Not a KEX value, but here so all the algorithm defaults are together */
 #define SSH_ALLOWED_CA_SIGALGS  \
         HOSTKEY_ECDSA_METHODS \
-        USERKEY_ECDSA_SK_METHODS \
         "ssh-ed25519," \
         "sk-ssh-ed25519@openssh.com," \
         "rsa-sha2-512," \
         "rsa-sha2-256," \
         "ssh-rsa"
 
-#define PUBKEY_DEFAULT_PK_ALG   \
-        USERKEY_ECDSA_SK_CERT_METHODS \
-        HOSTKEY_ECDSA_CERT_METHODS \
-        "sk-ssh-ed25519-cert-v01@openssh.com," \
-        "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," \
-        USERKEY_ECDSA_SK_METHODS \
-        HOSTKEY_ECDSA_METHODS \
-        "sk-ssh-ed25519@openssh.com," \
-        "ssh-ed25519," \
-        "rsa-sha2-512," \
-        "rsa-sha2-256," \
-        "ssh-rsa"
-
 #else /* WITH_OPENSSL */
 
 #define KEX_SERVER_KEX          \
@@ -176,7 +159,6 @@
 #define KEX_DEFAULT_PK_ALG      \
         "ssh-ed25519-cert-v01@openssh.com," \
         "ssh-ed25519"
-#define PUBKEY_DEFAULT_PK_ALG KEX_DEFAULT_PK_ALG
 #define KEX_SERVER_ENCRYPT \
         "chacha20-poly1305@openssh.com," \
         "aes128-ctr,aes192-ctr,aes256-ctr"