pull post-quantum ML-KEM/x25519 key exchange out from compile-time

flag now than an IANA codepoint has been assigned for the algorithm.

Add mlkem768x25519-sha256 in 2nd KexAlgorithms preference slot.

ok markus@

diff --git a/usr.bin/ssh/Makefile.inc b/usr.bin/ssh/Makefile.inc
index 4b7b302..772d745 100644 (file)
--- a/usr.bin/ssh/Makefile.inc
+++ b/usr.bin/ssh/Makefile.inc
@@ -1,4 +1,4 @@
-#      $OpenBSD: Makefile.inc,v 1.95 2024/09/02 12:13:56 djm Exp $
+#      $OpenBSD: Makefile.inc,v 1.96 2024/09/09 02:39:57 djm Exp $
 
 .include <bsd.own.mk>
 
@@ -38,8 +38,6 @@ WARNINGS=yes
 OPENSSL?=      yes
 ZLIB?=         yes
 DSAKEY?=       no
-# NB. experimental; Internet-draft subject to change.
-MLKEM?=                no
 
 .if (${OPENSSL:L} == "yes")
 CFLAGS+=       -DWITH_OPENSSL
@@ -53,10 +51,6 @@ CFLAGS+=     -DWITH_ZLIB
 CFLAGS+=       -DWITH_DSA
 .endif
 
-.if (${MLKEM:L} == "yes")
-CFLAGS+=       -DWITH_MLKEM
-.endif
-
 CFLAGS+=       -DENABLE_PKCS11
 .ifndef NOPIC
 CFLAGS+=       -DHAVE_DLOPEN
@@ -86,9 +80,7 @@ SRCS_KEX+=    smult_curve25519_ref.c
 SRCS_KEX+=     kexgen.c
 SRCS_KEX+=     kexsntrup761x25519.c
 SRCS_KEX+=     sntrup761.c
-.if (${MLKEM:L} == "yes")
 SRCS_KEX+=     kexmlkem768x25519.c
-.endif
 
 SRCS_KEY+=     sshkey.c
 SRCS_KEY+=     cipher.c

diff --git a/usr.bin/ssh/kex-names.c b/usr.bin/ssh/kex-names.c
index cb21819..ffaad7f 100644 (file)
--- a/usr.bin/ssh/kex-names.c
+++ b/usr.bin/ssh/kex-names.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kex-names.c,v 1.3 2024/09/02 12:13:56 djm Exp $ */
+/* $OpenBSD: kex-names.c,v 1.4 2024/09/09 02:39:57 djm Exp $ */
 /*
  * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
  *
@@ -72,10 +72,8 @@ static const struct kexalg kexalgs[] = {
            SSH_DIGEST_SHA512 },
        { KEX_SNTRUP761X25519_SHA512_OLD, KEX_KEM_SNTRUP761X25519_SHA512, 0,
            SSH_DIGEST_SHA512 },
-#ifdef WITH_MLKEM
        { KEX_MLKEM768X25519_SHA256, KEX_KEM_MLKEM768X25519_SHA256, 0,
            SSH_DIGEST_SHA256 },
-#endif
        { NULL, 0, -1, -1},
 };
 

diff --git a/usr.bin/ssh/kexgen.c b/usr.bin/ssh/kexgen.c
index 7968897..7a5a98e 100644 (file)
--- a/usr.bin/ssh/kexgen.c
+++ b/usr.bin/ssh/kexgen.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexgen.c,v 1.9 2024/09/02 12:13:56 djm Exp $ */
+/* $OpenBSD: kexgen.c,v 1.10 2024/09/09 02:39:57 djm Exp $ */
 /*
  * Copyright (c) 2019 Markus Friedl.  All rights reserved.
  *
@@ -117,11 +117,9 @@ kex_gen_client(struct ssh *ssh)
        case KEX_KEM_SNTRUP761X25519_SHA512:
                r = kex_kem_sntrup761x25519_keypair(kex);
                break;
-#ifdef WITH_MLKEM
        case KEX_KEM_MLKEM768X25519_SHA256:
                r = kex_kem_mlkem768x25519_keypair(kex);
                break;
-#endif
        default:
                r = SSH_ERR_INVALID_ARGUMENT;
                break;
@@ -194,12 +192,10 @@ input_kex_gen_reply(int type, u_int32_t seq, struct ssh *ssh)
                r = kex_kem_sntrup761x25519_dec(kex, server_blob,
                    &shared_secret);
                break;
-#ifdef WITH_MLKEM
        case KEX_KEM_MLKEM768X25519_SHA256:
                r = kex_kem_mlkem768x25519_dec(kex, server_blob,
                    &shared_secret);
                break;
-#endif
        default:
                r = SSH_ERR_INVALID_ARGUMENT;
                break;
@@ -320,12 +316,10 @@ input_kex_gen_init(int type, u_int32_t seq, struct ssh *ssh)
                r = kex_kem_sntrup761x25519_enc(kex, client_pubkey,
                    &server_pubkey, &shared_secret);
                break;
-#ifdef WITH_MLKEM
        case KEX_KEM_MLKEM768X25519_SHA256:
                r = kex_kem_mlkem768x25519_enc(kex, client_pubkey,
                    &server_pubkey, &shared_secret);
                break;
-#endif
        default:
                r = SSH_ERR_INVALID_ARGUMENT;
                break;

diff --git a/usr.bin/ssh/monitor.c b/usr.bin/ssh/monitor.c
index 255e37e..eea5600 100644 (file)
--- a/usr.bin/ssh/monitor.c
+++ b/usr.bin/ssh/monitor.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: monitor.c,v 1.241 2024/09/02 12:13:56 djm Exp $ */
+/* $OpenBSD: monitor.c,v 1.242 2024/09/09 02:39:57 djm Exp $ */
 /*
  * Copyright 2002 Niels Provos <provos@citi.umich.edu>
  * Copyright 2002 Markus Friedl <markus@openbsd.org>
@@ -1456,9 +1456,7 @@ monitor_apply_keystate(struct ssh *ssh, struct monitor *pmonitor)
 #endif
        kex->kex[KEX_C25519_SHA256] = kex_gen_server;
        kex->kex[KEX_KEM_SNTRUP761X25519_SHA512] = kex_gen_server;
-#ifdef WITH_MLKEM
        kex->kex[KEX_KEM_MLKEM768X25519_SHA256] = kex_gen_server;
-#endif
        kex->load_host_public_key=&get_hostkey_public_by_type;
        kex->load_host_private_key=&get_hostkey_private_by_type;
        kex->host_key_index=&get_hostkey_index;

diff --git a/usr.bin/ssh/myproposal.h b/usr.bin/ssh/myproposal.h
index bef6569..3bdc2e9 100644 (file)
--- a/usr.bin/ssh/myproposal.h
+++ b/usr.bin/ssh/myproposal.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: myproposal.h,v 1.72 2024/08/22 23:11:30 djm Exp $ */
+/* $OpenBSD: myproposal.h,v 1.73 2024/09/09 02:39:57 djm Exp $ */
 
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
@@ -27,6 +27,7 @@
 #define KEX_SERVER_KEX \
        "sntrup761x25519-sha512," \
        "sntrup761x25519-sha512@openssh.com," \
+       "mlkem768x25519-sha256," \
        "curve25519-sha256," \
        "curve25519-sha256@libssh.org," \
        "ecdh-sha2-nistp256," \

diff --git a/usr.bin/ssh/ssh-keyscan.c b/usr.bin/ssh/ssh-keyscan.c
index a204391..df8abc2 100644 (file)
--- a/usr.bin/ssh/ssh-keyscan.c
+++ b/usr.bin/ssh/ssh-keyscan.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-keyscan.c,v 1.160 2024/09/04 05:33:34 djm Exp $ */
+/* $OpenBSD: ssh-keyscan.c,v 1.161 2024/09/09 02:39:57 djm Exp $ */
 /*
  * Copyright 1995, 1996 by David Mazieres <dm@lcs.mit.edu>.
  *
@@ -277,9 +277,7 @@ keygrab_ssh2(con *c)
 #endif
        c->c_ssh->kex->kex[KEX_C25519_SHA256] = kex_gen_client;
        c->c_ssh->kex->kex[KEX_KEM_SNTRUP761X25519_SHA512] = kex_gen_client;
-#ifdef WITH_MLKEM
        c->c_ssh->kex->kex[KEX_KEM_MLKEM768X25519_SHA256] = kex_gen_client;
-#endif
        ssh_set_verify_host_key_callback(c->c_ssh, key_print_wrapper);
        /*
         * do the key-exchange until an error occurs or until

diff --git a/usr.bin/ssh/ssh_api.c b/usr.bin/ssh/ssh_api.c
index 9897bb8..1a83880 100644 (file)
--- a/usr.bin/ssh/ssh_api.c
+++ b/usr.bin/ssh/ssh_api.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh_api.c,v 1.30 2024/09/02 12:13:56 djm Exp $ */
+/* $OpenBSD: ssh_api.c,v 1.31 2024/09/09 02:39:57 djm Exp $ */
 /*
  * Copyright (c) 2012 Markus Friedl.  All rights reserved.
  *
@@ -130,9 +130,7 @@ ssh_init(struct ssh **sshp, int is_server, struct kex_params *kex_params)
 #endif /* WITH_OPENSSL */
                ssh->kex->kex[KEX_C25519_SHA256] = kex_gen_server;
                ssh->kex->kex[KEX_KEM_SNTRUP761X25519_SHA512] = kex_gen_server;
-#ifdef WITH_MLKEM
                ssh->kex->kex[KEX_KEM_MLKEM768X25519_SHA256] = kex_gen_server;
-#endif
                ssh->kex->load_host_public_key=&_ssh_host_public_key;
                ssh->kex->load_host_private_key=&_ssh_host_private_key;
                ssh->kex->sign=&_ssh_host_key_sign;
@@ -149,9 +147,7 @@ ssh_init(struct ssh **sshp, int is_server, struct kex_params *kex_params)
 #endif /* WITH_OPENSSL */
                ssh->kex->kex[KEX_C25519_SHA256] = kex_gen_client;
                ssh->kex->kex[KEX_KEM_SNTRUP761X25519_SHA512] = kex_gen_client;
-#ifdef WITH_MLKEM
                ssh->kex->kex[KEX_KEM_MLKEM768X25519_SHA256] = kex_gen_client;
-#endif
                ssh->kex->verify_host_key =&_ssh_verify_host_key;
        }
        *sshp = ssh;

diff --git a/usr.bin/ssh/sshconnect2.c b/usr.bin/ssh/sshconnect2.c
index 0228cbc..5ad2ac4 100644 (file)
--- a/usr.bin/ssh/sshconnect2.c
+++ b/usr.bin/ssh/sshconnect2.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshconnect2.c,v 1.374 2024/09/02 12:13:56 djm Exp $ */
+/* $OpenBSD: sshconnect2.c,v 1.375 2024/09/09 02:39:57 djm Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  * Copyright (c) 2008 Damien Miller.  All rights reserved.
@@ -267,9 +267,7 @@ ssh_kex2(struct ssh *ssh, char *host, struct sockaddr *hostaddr, u_short port,
 #endif
        ssh->kex->kex[KEX_C25519_SHA256] = kex_gen_client;
        ssh->kex->kex[KEX_KEM_SNTRUP761X25519_SHA512] = kex_gen_client;
-#ifdef WITH_MLKEM
        ssh->kex->kex[KEX_KEM_MLKEM768X25519_SHA256] = kex_gen_client;
-#endif
        ssh->kex->verify_host_key=&verify_host_key_callback;
 
        ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &ssh->kex->done);

diff --git a/usr.bin/ssh/sshd-session.c b/usr.bin/ssh/sshd-session.c
index 64502af..e4b698d 100644 (file)
--- a/usr.bin/ssh/sshd-session.c
+++ b/usr.bin/ssh/sshd-session.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshd-session.c,v 1.8 2024/09/02 12:18:35 djm Exp $ */
+/* $OpenBSD: sshd-session.c,v 1.9 2024/09/09 02:39:57 djm Exp $ */
 /*
  * SSH2 implementation:
  * Privilege Separation:
@@ -1334,9 +1334,7 @@ do_ssh2_kex(struct ssh *ssh)
 #endif
        kex->kex[KEX_C25519_SHA256] = kex_gen_server;
        kex->kex[KEX_KEM_SNTRUP761X25519_SHA512] = kex_gen_server;
-#ifdef WITH_MLKEM
        kex->kex[KEX_KEM_MLKEM768X25519_SHA256] = kex_gen_server;
-#endif
        kex->load_host_public_key=&get_hostkey_public_by_type;
        kex->load_host_private_key=&get_hostkey_private_by_type;
        kex->host_key_index=&get_hostkey_index;