use KEM API for vanilla DH KEX

from markus@ ok djm@

12 files changed, 155 insertions, 371 deletions

diff --git a/usr.bin/ssh/Makefile.inc b/usr.bin/ssh/Makefile.inc
index 52c769712aa..60360a200b7 100644
--- a/usr.bin/ssh/Makefile.inc
+++ b/usr.bin/ssh/Makefile.inc
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.inc,v 1.63 2019/01/21 10:24:09 djm Exp $
+#	$OpenBSD: Makefile.inc,v 1.64 2019/01/21 10:28:01 djm Exp $
 
 .include <bsd.own.mk>
 
@@ -49,10 +49,8 @@ SRCS_KEX+=	dh.c
 SRCS_KEX+=	kexdh.c
 SRCS_KEX+=	kexecdh.c
 SRCS_KEX+=	kexgex.c
-SRCS_KEXC+=	kexdhc.c
 SRCS_KEXC+=	kexecdhc.c
 SRCS_KEXC+=	kexgexc.c
-SRCS_KEXS+=	kexdhs.c
 SRCS_KEXS+=	kexecdhs.c
 SRCS_KEXS+=	kexgexs.c
 .endif
diff --git a/usr.bin/ssh/kex.h b/usr.bin/ssh/kex.h
index 57f78a27af9..eef75db497a 100644
--- a/usr.bin/ssh/kex.h
+++ b/usr.bin/ssh/kex.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: kex.h,v 1.100 2019/01/21 10:24:09 djm Exp $ */
+/* $OpenBSD: kex.h,v 1.101 2019/01/21 10:28:01 djm Exp $ */
 
 /*
  * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
@@ -195,6 +195,11 @@ int	 kexc25519_server(struct ssh *);
 int	 kex_kem_client(struct ssh *);
 int	 kex_kem_server(struct ssh *);
 
+int	 kex_dh_keypair(struct kex *);
+int	 kex_dh_enc(struct kex *, const u_char *, size_t, struct sshbuf **,
+    struct sshbuf **);
+int	 kex_dh_dec(struct kex *, const u_char *, size_t, struct sshbuf **);
+
 int	 kex_c25519_keypair(struct kex *);
 int	 kex_c25519_enc(struct kex *, const u_char *, size_t, struct sshbuf **,
     struct sshbuf **);
@@ -208,9 +213,6 @@ int	 kex_kem_sntrup4591761x25519_dec(struct kex *, const u_char *, size_t,
 
 int	 kex_dh_keygen(struct kex *);
 int	 kex_dh_compute_key(struct kex *, BIGNUM *, struct sshbuf *);
-int	 kex_dh_hash(int, const struct sshbuf *, const struct sshbuf *,
-    const u_char *, size_t, const u_char *, size_t, const u_char *, size_t,
-    const BIGNUM *, const BIGNUM *, const u_char *, size_t, u_char *, size_t *);
 
 int	 kexgex_hash(int, const struct sshbuf *, const struct sshbuf *,
     const u_char *, size_t, const u_char *, size_t, const u_char *, size_t,
diff --git a/usr.bin/ssh/kexdh.c b/usr.bin/ssh/kexdh.c
index 6f35e57c368..a59dd21036f 100644
--- a/usr.bin/ssh/kexdh.c
+++ b/usr.bin/ssh/kexdh.c
@@ -1,6 +1,6 @@
-/* $OpenBSD: kexdh.c,v 1.29 2019/01/21 10:03:37 djm Exp $ */
+/* $OpenBSD: kexdh.c,v 1.30 2019/01/21 10:28:01 djm Exp $ */
 /*
- * Copyright (c) 2001 Markus Friedl.  All rights reserved.
+ * Copyright (c) 2019 Markus Friedl.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -25,18 +25,15 @@
 
 #include <sys/types.h>
 
+#include <stdio.h>
+#include <string.h>
 #include <signal.h>
 
-#include <openssl/evp.h>
-
-#include "ssh2.h"
 #include "sshkey.h"
-#include "cipher.h"
 #include "kex.h"
-#include "dh.h"
-#include "ssherr.h"
 #include "sshbuf.h"
 #include "digest.h"
+#include "ssherr.h"
 #include "dh.h"
 
 int
@@ -107,52 +104,94 @@ kex_dh_compute_key(struct kex *kex, BIGNUM *dh_pub, struct sshbuf *out)
 }
 
 int
-kex_dh_hash(
-    int hash_alg,
-    const struct sshbuf *client_version,
-    const struct sshbuf *server_version,
-    const u_char *ckexinit, size_t ckexinitlen,
-    const u_char *skexinit, size_t skexinitlen,
-    const u_char *serverhostkeyblob, size_t sbloblen,
-    const BIGNUM *client_dh_pub,
-    const BIGNUM *server_dh_pub,
-    const u_char *shared_secret, size_t secretlen,
-    u_char *hash, size_t *hashlen)
+kex_dh_keypair(struct kex *kex)
 {
-	struct sshbuf *b;
+	const BIGNUM *pub_key;
+	struct sshbuf *buf = NULL;
 	int r;
 
-	if (*hashlen < ssh_digest_bytes(hash_alg))
-		return SSH_ERR_INVALID_ARGUMENT;
-	if ((b = sshbuf_new()) == NULL)
-		return SSH_ERR_ALLOC_FAIL;
-	if ((r = sshbuf_put_stringb(b, client_version)) < 0 ||
-	    (r = sshbuf_put_stringb(b, server_version)) < 0 ||
-	    /* kexinit messages: fake header: len+SSH2_MSG_KEXINIT */
-	    (r = sshbuf_put_u32(b, ckexinitlen+1)) != 0 ||
-	    (r = sshbuf_put_u8(b, SSH2_MSG_KEXINIT)) != 0 ||
-	    (r = sshbuf_put(b, ckexinit, ckexinitlen)) != 0 ||
-	    (r = sshbuf_put_u32(b, skexinitlen+1)) != 0 ||
-	    (r = sshbuf_put_u8(b, SSH2_MSG_KEXINIT)) != 0 ||
-	    (r = sshbuf_put(b, skexinit, skexinitlen)) != 0 ||
-	    (r = sshbuf_put_string(b, serverhostkeyblob, sbloblen)) != 0 ||
-	    (r = sshbuf_put_bignum2(b, client_dh_pub)) != 0 ||
-	    (r = sshbuf_put_bignum2(b, server_dh_pub)) != 0 ||
-	    (r = sshbuf_put(b, shared_secret, secretlen)) != 0) {
-		sshbuf_free(b);
+	if ((r = kex_dh_keygen(kex)) != 0)
 		return r;
-	}
-#ifdef DEBUG_KEX
-	sshbuf_dump(b, stderr);
+	DH_get0_key(kex->dh, &pub_key, NULL);
+	if ((buf = sshbuf_new()) == NULL)
+		return SSH_ERR_ALLOC_FAIL;
+	if ((r = sshbuf_put_bignum2(buf, pub_key)) != 0 ||
+	    (r = sshbuf_get_u32(buf, NULL)) != 0)
+		goto out;
+#ifdef DEBUG_KEXDH
+	DHparams_print_fp(stderr, kex->dh);
+	fprintf(stderr, "pub= ");
+	BN_print_fp(stderr, pub_key);
+	fprintf(stderr, "\n");
 #endif
-	if (ssh_digest_buffer(hash_alg, b, hash, *hashlen) != 0) {
-		sshbuf_free(b);
-		return SSH_ERR_LIBCRYPTO_ERROR;
+	kex->kem_client_pub = buf;
+	buf = NULL;
+ out:
+	sshbuf_free(buf);
+	return r;
+}
+
+int
+kex_dh_enc(struct kex *kex, const u_char *pkblob, size_t pklen,
+    struct sshbuf **server_blobp, struct sshbuf **shared_secretp)
+{
+	const BIGNUM *pub_key;
+	struct sshbuf *server_blob = NULL;
+	int r;
+
+	*server_blobp = NULL;
+	*shared_secretp = NULL;
+
+	if ((r = kex_dh_keygen(kex)) != 0)
+		goto out;
+	DH_get0_key(kex->dh, &pub_key, NULL);
+	if ((server_blob = sshbuf_new()) == NULL) {
+		r = SSH_ERR_ALLOC_FAIL;
+		goto out;
 	}
-	sshbuf_free(b);
-	*hashlen = ssh_digest_bytes(hash_alg);
-#ifdef DEBUG_KEX
-	dump_digest("hash", hash, *hashlen);
-#endif
-	return 0;
+	if ((r = sshbuf_put_bignum2(server_blob, pub_key)) != 0 ||
+	    (r = sshbuf_get_u32(server_blob, NULL)) != 0)
+		goto out;
+	if ((r = kex_dh_dec(kex, pkblob, pklen, shared_secretp)) != 0)
+		goto out;
+	*server_blobp = server_blob;
+	server_blob = NULL;
+ out:
+	DH_free(kex->dh);
+	kex->dh = NULL;
+	sshbuf_free(server_blob);
+	return r;
+}
+
+int
+kex_dh_dec(struct kex *kex, const u_char *pkblob, size_t pklen,
+    struct sshbuf **shared_secretp)
+{
+	struct sshbuf *buf = NULL;
+	BIGNUM *dh_pub = NULL;
+	int r;
+
+	*shared_secretp = NULL;
+
+	if ((buf = sshbuf_new()) == NULL) {
+		r = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+	if ((r = sshbuf_put_u32(buf, pklen)) != 0 ||
+	    (r = sshbuf_put(buf, pkblob, pklen)) != 0) {
+		goto out;
+	}
+	if ((r = sshbuf_get_bignum2(buf, &dh_pub)) != 0) {
+		goto out;
+	}
+	sshbuf_reset(buf);
+	if ((r = kex_dh_compute_key(kex, dh_pub, buf)) != 0)
+		goto out;
+	*shared_secretp = buf;
+	buf = NULL;
+ out:
+	DH_free(kex->dh);
+	kex->dh = NULL;
+	sshbuf_free(buf);
+	return r;
 }
diff --git a/usr.bin/ssh/kexdhc.c b/usr.bin/ssh/kexdhc.c
deleted file mode 100644
index ca81b2d9e3d..00000000000
--- a/usr.bin/ssh/kexdhc.c
+++ /dev/null
@@ -1,143 +0,0 @@
-/* $OpenBSD: kexdhc.c,v 1.29 2019/01/21 10:07:22 djm Exp $ */
-/*
- * Copyright (c) 2001 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 <sys/types.h>
-
-#include <openssl/dh.h>
-
-#include <stdio.h>
-#include <string.h>
-#include <signal.h>
-
-#include "sshkey.h"
-#include "cipher.h"
-#include "digest.h"
-#include "dh.h"
-#include "kex.h"
-#include "log.h"
-#include "packet.h"
-#include "ssh2.h"
-#include "dispatch.h"
-#include "compat.h"
-#include "ssherr.h"
-#include "sshbuf.h"
-
-static int input_kex_dh(int, u_int32_t, struct ssh *);
-
-int
-kexdh_client(struct ssh *ssh)
-{
-	struct kex *kex = ssh->kex;
-	int r;
-	const BIGNUM *pub_key;
-
-	/* generate and send 'e', client DH public key */
-	if ((r = kex_dh_keygen(kex)) != 0)
-		goto out;
-	debug("sending SSH2_MSG_KEXDH_INIT");
-	DH_get0_key(kex->dh, &pub_key, NULL);
-	if ((r = sshpkt_start(ssh, SSH2_MSG_KEXDH_INIT)) != 0 ||
-	    (r = sshpkt_put_bignum2(ssh, pub_key)) != 0 ||
-	    (r = sshpkt_send(ssh)) != 0)
-		goto out;
-#ifdef DEBUG_KEXDH
-	DHparams_print_fp(stderr, kex->dh);
-	fprintf(stderr, "pub= ");
-	BN_print_fp(stderr, pub_key);
-	fprintf(stderr, "\n");
-#endif
-	debug("expecting SSH2_MSG_KEXDH_REPLY");
-	ssh_dispatch_set(ssh, SSH2_MSG_KEXDH_REPLY, &input_kex_dh);
-	r = 0;
- out:
-	return r;
-}
-
-static int
-input_kex_dh(int type, u_int32_t seq, struct ssh *ssh)
-{
-	struct kex *kex = ssh->kex;
-	BIGNUM *dh_server_pub = NULL;
-	const BIGNUM *pub_key;
-	struct sshkey *server_host_key = NULL;
-	struct sshbuf *shared_secret = NULL;
-	u_char *server_host_key_blob = NULL, *signature = NULL;
-	u_char hash[SSH_DIGEST_MAX_LENGTH];
-	size_t slen, sbloblen, hashlen;
-	int r;
-
-	/* key, cert */
-	if ((r = sshpkt_get_string(ssh, &server_host_key_blob,
-	    &sbloblen)) != 0 ||
-	    (r = sshkey_from_blob(server_host_key_blob, sbloblen,
-	    &server_host_key)) != 0)
-		goto out;
-	if ((r = kex_verify_host_key(ssh, server_host_key)) != 0)
-		goto out;
-	/* DH parameter f, server public DH key, signed H */
-	if ((r = sshpkt_get_bignum2(ssh, &dh_server_pub)) != 0 ||
-	    (r = sshpkt_get_string(ssh, &signature, &slen)) != 0 ||
-	    (r = sshpkt_get_end(ssh)) != 0)
-		goto out;
-	if ((shared_secret = sshbuf_new()) == NULL) {
-		r = SSH_ERR_ALLOC_FAIL;
-		goto out;
-	}
-	if ((r = kex_dh_compute_key(kex, dh_server_pub, shared_secret)) != 0)
-		goto out;
-
-	/* calc and verify H */
-	DH_get0_key(kex->dh, &pub_key, NULL);
-	hashlen = sizeof(hash);
-	if ((r = kex_dh_hash(
-	    kex->hash_alg,
-	    kex->client_version,
-	    kex->server_version,
-	    sshbuf_ptr(kex->my), sshbuf_len(kex->my),
-	    sshbuf_ptr(kex->peer), sshbuf_len(kex->peer),
-	    server_host_key_blob, sbloblen,
-	    pub_key,
-	    dh_server_pub,
-	    sshbuf_ptr(shared_secret), sshbuf_len(shared_secret),
-	    hash, &hashlen)) != 0)
-		goto out;
-
-	if ((r = sshkey_verify(server_host_key, signature, slen, hash, hashlen,
-	    kex->hostkey_alg, ssh->compat)) != 0)
-		goto out;
-
-	if ((r = kex_derive_keys(ssh, hash, hashlen, shared_secret)) == 0)
-		r = kex_send_newkeys(ssh);
- out:
-	explicit_bzero(hash, sizeof(hash));
-	DH_free(kex->dh);
-	kex->dh = NULL;
-	BN_clear_free(dh_server_pub);
-	sshbuf_free(shared_secret);
-	sshkey_free(server_host_key);
-	free(server_host_key_blob);
-	free(signature);
-	return r;
-}
diff --git a/usr.bin/ssh/kexdhs.c b/usr.bin/ssh/kexdhs.c
deleted file mode 100644
index f0cca9b5835..00000000000
--- a/usr.bin/ssh/kexdhs.c
+++ /dev/null
@@ -1,134 +0,0 @@
-/* $OpenBSD: kexdhs.c,v 1.35 2019/01/21 10:05:09 djm Exp $ */
-/*
- * Copyright (c) 2001 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 <sys/types.h>
-#include <string.h>
-#include <signal.h>
-
-#include <openssl/dh.h>
-
-#include "sshkey.h"
-#include "cipher.h"
-#include "digest.h"
-#include "dh.h"
-#include "kex.h"
-#include "log.h"
-#include "packet.h"
-#include "ssh2.h"
-
-#include "dispatch.h"
-#include "compat.h"
-#include "ssherr.h"
-#include "sshbuf.h"
-
-static int input_kex_dh_init(int, u_int32_t, struct ssh *);
-
-int
-kexdh_server(struct ssh *ssh)
-{
-	struct kex *kex = ssh->kex;
-	int r;
-
-	/* generate server DH public key */
-	if ((r = kex_dh_keygen(kex)) != 0)
-		return r;
-	debug("expecting SSH2_MSG_KEXDH_INIT");
-	ssh_dispatch_set(ssh, SSH2_MSG_KEXDH_INIT, &input_kex_dh_init);
-	return 0;
-}
-
-int
-input_kex_dh_init(int type, u_int32_t seq, struct ssh *ssh)
-{
-	struct kex *kex = ssh->kex;
-	BIGNUM *dh_client_pub = NULL;
-	const BIGNUM *pub_key;
-	struct sshkey *server_host_public, *server_host_private;
-	struct sshbuf *shared_secret = NULL;
-	u_char *signature = NULL, *server_host_key_blob = NULL;
-	u_char hash[SSH_DIGEST_MAX_LENGTH];
-	size_t sbloblen, slen;
-	size_t hashlen;
-	int r;
-
-	if ((r = kex_load_hostkey(ssh, &server_host_private,
-	    &server_host_public)) != 0)
-		goto out;
-
-	/* key, cert */
-	if ((r = sshpkt_get_bignum2(ssh, &dh_client_pub)) != 0 ||
-	    (r = sshpkt_get_end(ssh)) != 0)
-		goto out;
-	if ((shared_secret = sshbuf_new()) == NULL) {
-		r = SSH_ERR_ALLOC_FAIL;
-		goto out;
-	}
-	if ((r = kex_dh_compute_key(kex, dh_client_pub, shared_secret)) != 0)
-		goto out;
-	if ((r = sshkey_to_blob(server_host_public, &server_host_key_blob,
-	    &sbloblen)) != 0)
-		goto out;
-	/* calc H */
-	DH_get0_key(kex->dh, &pub_key, NULL);
-	hashlen = sizeof(hash);
-	if ((r = kex_dh_hash(
-	    kex->hash_alg,
-	    kex->client_version,
-	    kex->server_version,
-	    sshbuf_ptr(kex->peer), sshbuf_len(kex->peer),
-	    sshbuf_ptr(kex->my), sshbuf_len(kex->my),
-	    server_host_key_blob, sbloblen,
-	    dh_client_pub,
-	    pub_key,
-	    sshbuf_ptr(shared_secret), sshbuf_len(shared_secret),
-	    hash, &hashlen)) != 0)
-		goto out;
-
-	/* sign H */
-	if ((r = kex->sign(ssh, server_host_private, server_host_public,
-	    &signature, &slen, hash, hashlen, kex->hostkey_alg)) < 0)
-		goto out;
-
-	/* send server hostkey, DH pubkey 'f' and signed H */
-	if ((r = sshpkt_start(ssh, SSH2_MSG_KEXDH_REPLY)) != 0 ||
-	    (r = sshpkt_put_string(ssh, server_host_key_blob, sbloblen)) != 0 ||
-	    (r = sshpkt_put_bignum2(ssh, pub_key)) != 0 ||	/* f */
-	    (r = sshpkt_put_string(ssh, signature, slen)) != 0 ||
-	    (r = sshpkt_send(ssh)) != 0)
-		goto out;
-
-	if ((r = kex_derive_keys(ssh, hash, hashlen, shared_secret)) == 0)
-		r = kex_send_newkeys(ssh);
- out:
-	explicit_bzero(hash, sizeof(hash));
-	DH_free(kex->dh);
-	kex->dh = NULL;
-	BN_clear_free(dh_client_pub);
-	sshbuf_free(shared_secret);
-	free(server_host_key_blob);
-	free(signature);
-	return r;
-}
diff --git a/usr.bin/ssh/kexkemc.c b/usr.bin/ssh/kexkemc.c
index 13f36a1160a..384a4db598c 100644
--- a/usr.bin/ssh/kexkemc.c
+++ b/usr.bin/ssh/kexkemc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexkemc.c,v 1.2 2019/01/21 10:24:09 djm Exp $ */
+/* $OpenBSD: kexkemc.c,v 1.3 2019/01/21 10:28:02 djm Exp $ */
 /*
  * Copyright (c) 2019 Markus Friedl.  All rights reserved.
  *
@@ -48,6 +48,13 @@ kex_kem_client(struct ssh *ssh)
 	int r;
 
 	switch (kex->kex_type) {
+	case KEX_DH_GRP1_SHA1:
+	case KEX_DH_GRP14_SHA1:
+	case KEX_DH_GRP14_SHA256:
+	case KEX_DH_GRP16_SHA512:
+	case KEX_DH_GRP18_SHA512:
+		r = kex_dh_keypair(kex);
+		break;
 	case KEX_C25519_SHA256:
 		r = kex_c25519_keypair(kex);
 		break;
@@ -99,6 +106,13 @@ input_kex_kem_reply(int type, u_int32_t seq, struct ssh *ssh)
 
 	/* compute shared secret */
 	switch (kex->kex_type) {
+	case KEX_DH_GRP1_SHA1:
+	case KEX_DH_GRP14_SHA1:
+	case KEX_DH_GRP14_SHA256:
+	case KEX_DH_GRP16_SHA512:
+	case KEX_DH_GRP18_SHA512:
+		r = kex_dh_dec(kex, server_pubkey, pklen, &shared_secret);
+		break;
 	case KEX_C25519_SHA256:
 		r = kex_c25519_dec(kex, server_pubkey, pklen, &shared_secret);
 		break;
diff --git a/usr.bin/ssh/kexkems.c b/usr.bin/ssh/kexkems.c
index 89237902bf4..f35906d53d2 100644
--- a/usr.bin/ssh/kexkems.c
+++ b/usr.bin/ssh/kexkems.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexkems.c,v 1.2 2019/01/21 10:24:09 djm Exp $ */
+/* $OpenBSD: kexkems.c,v 1.3 2019/01/21 10:28:02 djm Exp $ */
 /*
  * Copyright (c) 2019 Markus Friedl.  All rights reserved.
  *
@@ -69,6 +69,14 @@ input_kex_kem_init(int type, u_int32_t seq, struct ssh *ssh)
 
 	/* compute shared secret */
 	switch (kex->kex_type) {
+	case KEX_DH_GRP1_SHA1:
+	case KEX_DH_GRP14_SHA1:
+	case KEX_DH_GRP14_SHA256:
+	case KEX_DH_GRP16_SHA512:
+	case KEX_DH_GRP18_SHA512:
+		r = kex_dh_enc(kex, client_pubkey, pklen, &server_pubkey,
+		    &shared_secret);
+		break;
 	case KEX_C25519_SHA256:
 		r = kex_c25519_enc(kex, client_pubkey, pklen, &server_pubkey,
 		    &shared_secret);
diff --git a/usr.bin/ssh/monitor.c b/usr.bin/ssh/monitor.c
index 2f77d5cf181..524b95db3fa 100644
--- a/usr.bin/ssh/monitor.c
+++ b/usr.bin/ssh/monitor.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: monitor.c,v 1.194 2019/01/21 10:24:09 djm Exp $ */
+/* $OpenBSD: monitor.c,v 1.195 2019/01/21 10:28:02 djm Exp $ */
 /*
  * Copyright 2002 Niels Provos <provos@citi.umich.edu>
  * Copyright 2002 Markus Friedl <markus@openbsd.org>
@@ -1381,11 +1381,11 @@ monitor_apply_keystate(struct ssh *ssh, struct monitor *pmonitor)
 	if ((kex = ssh->kex) != NULL) {
 		/* XXX set callbacks */
 #ifdef WITH_OPENSSL
-		kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
-		kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
-		kex->kex[KEX_DH_GRP14_SHA256] = kexdh_server;
-		kex->kex[KEX_DH_GRP16_SHA512] = kexdh_server;
-		kex->kex[KEX_DH_GRP18_SHA512] = kexdh_server;
+		kex->kex[KEX_DH_GRP1_SHA1] = kex_kem_server;
+		kex->kex[KEX_DH_GRP14_SHA1] = kex_kem_server;
+		kex->kex[KEX_DH_GRP14_SHA256] = kex_kem_server;
+		kex->kex[KEX_DH_GRP16_SHA512] = kex_kem_server;
+		kex->kex[KEX_DH_GRP18_SHA512] = kex_kem_server;
 		kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
 		kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
 		kex->kex[KEX_ECDH_SHA2] = kexecdh_server;
diff --git a/usr.bin/ssh/ssh-keyscan.c b/usr.bin/ssh/ssh-keyscan.c
index 2c41697ab3e..c2b6c9eae4c 100644
--- a/usr.bin/ssh/ssh-keyscan.c
+++ b/usr.bin/ssh/ssh-keyscan.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-keyscan.c,v 1.122 2019/01/21 10:24:09 djm Exp $ */
+/* $OpenBSD: ssh-keyscan.c,v 1.123 2019/01/21 10:28:02 djm Exp $ */
 /*
  * Copyright 1995, 1996 by David Mazieres <dm@lcs.mit.edu>.
  *
@@ -244,11 +244,11 @@ keygrab_ssh2(con *c)
 		exit(1);
 	}
 #ifdef WITH_OPENSSL
-	c->c_ssh->kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
-	c->c_ssh->kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
-	c->c_ssh->kex->kex[KEX_DH_GRP14_SHA256] = kexdh_client;
-	c->c_ssh->kex->kex[KEX_DH_GRP16_SHA512] = kexdh_client;
-	c->c_ssh->kex->kex[KEX_DH_GRP18_SHA512] = kexdh_client;
+	c->c_ssh->kex->kex[KEX_DH_GRP1_SHA1] = kex_kem_client;
+	c->c_ssh->kex->kex[KEX_DH_GRP14_SHA1] = kex_kem_client;
+	c->c_ssh->kex->kex[KEX_DH_GRP14_SHA256] = kex_kem_client;
+	c->c_ssh->kex->kex[KEX_DH_GRP16_SHA512] = kex_kem_client;
+	c->c_ssh->kex->kex[KEX_DH_GRP18_SHA512] = kex_kem_client;
 	c->c_ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
 	c->c_ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
 	c->c_ssh->kex->kex[KEX_ECDH_SHA2] = kexecdh_client;
diff --git a/usr.bin/ssh/ssh_api.c b/usr.bin/ssh/ssh_api.c
index 26645eeaa84..c5e4ec9626a 100644
--- a/usr.bin/ssh/ssh_api.c
+++ b/usr.bin/ssh/ssh_api.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh_api.c,v 1.12 2019/01/21 10:24:09 djm Exp $ */
+/* $OpenBSD: ssh_api.c,v 1.13 2019/01/21 10:28:02 djm Exp $ */
 /*
  * Copyright (c) 2012 Markus Friedl.  All rights reserved.
  *
@@ -95,11 +95,11 @@ ssh_init(struct ssh **sshp, int is_server, struct kex_params *kex_params)
 	ssh->kex->server = is_server;
 	if (is_server) {
 #ifdef WITH_OPENSSL
-		ssh->kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
-		ssh->kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
-		ssh->kex->kex[KEX_DH_GRP14_SHA256] = kexdh_server;
-		ssh->kex->kex[KEX_DH_GRP16_SHA512] = kexdh_server;
-		ssh->kex->kex[KEX_DH_GRP18_SHA512] = kexdh_server;
+		ssh->kex->kex[KEX_DH_GRP1_SHA1] = kex_kem_server;
+		ssh->kex->kex[KEX_DH_GRP14_SHA1] = kex_kem_server;
+		ssh->kex->kex[KEX_DH_GRP14_SHA256] = kex_kem_server;
+		ssh->kex->kex[KEX_DH_GRP16_SHA512] = kex_kem_server;
+		ssh->kex->kex[KEX_DH_GRP18_SHA512] = kex_kem_server;
 		ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
 		ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
 		ssh->kex->kex[KEX_ECDH_SHA2] = kexecdh_server;
@@ -111,11 +111,11 @@ ssh_init(struct ssh **sshp, int is_server, struct kex_params *kex_params)
 		ssh->kex->sign=&_ssh_host_key_sign;
 	} else {
 #ifdef WITH_OPENSSL
-		ssh->kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
-		ssh->kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
-		ssh->kex->kex[KEX_DH_GRP14_SHA256] = kexdh_client;
-		ssh->kex->kex[KEX_DH_GRP16_SHA512] = kexdh_client;
-		ssh->kex->kex[KEX_DH_GRP18_SHA512] = kexdh_client;
+		ssh->kex->kex[KEX_DH_GRP1_SHA1] = kex_kem_client;
+		ssh->kex->kex[KEX_DH_GRP14_SHA1] = kex_kem_client;
+		ssh->kex->kex[KEX_DH_GRP14_SHA256] = kex_kem_client;
+		ssh->kex->kex[KEX_DH_GRP16_SHA512] = kex_kem_client;
+		ssh->kex->kex[KEX_DH_GRP18_SHA512] = kex_kem_client;
 		ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
 		ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
 		ssh->kex->kex[KEX_ECDH_SHA2] = kexecdh_client;
diff --git a/usr.bin/ssh/sshconnect2.c b/usr.bin/ssh/sshconnect2.c
index 761f1f3857d..ee6e30e165a 100644
--- a/usr.bin/ssh/sshconnect2.c
+++ b/usr.bin/ssh/sshconnect2.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshconnect2.c,v 1.298 2019/01/21 10:24:09 djm Exp $ */
+/* $OpenBSD: sshconnect2.c,v 1.299 2019/01/21 10:28:02 djm Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  * Copyright (c) 2008 Damien Miller.  All rights reserved.
@@ -195,11 +195,11 @@ ssh_kex2(struct ssh *ssh, char *host, struct sockaddr *hostaddr, u_short port)
 	if ((r = kex_setup(ssh, myproposal)) != 0)
 		fatal("kex_setup: %s", ssh_err(r));
 #ifdef WITH_OPENSSL
-	ssh->kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
-	ssh->kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
-	ssh->kex->kex[KEX_DH_GRP14_SHA256] = kexdh_client;
-	ssh->kex->kex[KEX_DH_GRP16_SHA512] = kexdh_client;
-	ssh->kex->kex[KEX_DH_GRP18_SHA512] = kexdh_client;
+	ssh->kex->kex[KEX_DH_GRP1_SHA1] = kex_kem_client;
+	ssh->kex->kex[KEX_DH_GRP14_SHA1] = kex_kem_client;
+	ssh->kex->kex[KEX_DH_GRP14_SHA256] = kex_kem_client;
+	ssh->kex->kex[KEX_DH_GRP16_SHA512] = kex_kem_client;
+	ssh->kex->kex[KEX_DH_GRP18_SHA512] = kex_kem_client;
 	ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
 	ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
 	ssh->kex->kex[KEX_ECDH_SHA2] = kexecdh_client;
diff --git a/usr.bin/ssh/sshd.c b/usr.bin/ssh/sshd.c
index bc9376ff264..d65fd78175e 100644
--- a/usr.bin/ssh/sshd.c
+++ b/usr.bin/ssh/sshd.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshd.c,v 1.529 2019/01/21 10:24:09 djm Exp $ */
+/* $OpenBSD: sshd.c,v 1.530 2019/01/21 10:28:02 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -2025,11 +2025,11 @@ do_ssh2_kex(struct ssh *ssh)
 		fatal("kex_setup: %s", ssh_err(r));
 	kex = ssh->kex;
 #ifdef WITH_OPENSSL
-	kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
-	kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
-	kex->kex[KEX_DH_GRP14_SHA256] = kexdh_server;
-	kex->kex[KEX_DH_GRP16_SHA512] = kexdh_server;
-	kex->kex[KEX_DH_GRP18_SHA512] = kexdh_server;
+	kex->kex[KEX_DH_GRP1_SHA1] = kex_kem_server;
+	kex->kex[KEX_DH_GRP14_SHA1] = kex_kem_server;
+	kex->kex[KEX_DH_GRP14_SHA256] = kex_kem_server;
+	kex->kex[KEX_DH_GRP16_SHA512] = kex_kem_server;
+	kex->kex[KEX_DH_GRP18_SHA512] = kex_kem_server;
 	kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
 	kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
 	kex->kex[KEX_ECDH_SHA2] = kexecdh_server;