Adding upstream version 1:7.9p1.upstream/1%7.9p1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 4165 insertions, 0 deletions

diff --git a/sshkey.c b/sshkey.c
new file mode 100644
index 0000000..6555c5e
--- /dev/null
+++ b/sshkey.c
@@ -0,0 +1,4165 @@
+/* $OpenBSD: sshkey.c,v 1.72 2018/10/11 00:52:46 djm Exp $ */
+/*
+ * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
+ * Copyright (c) 2008 Alexander von Gernler.  All rights reserved.
+ * Copyright (c) 2010,2011 Damien Miller.  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 "includes.h"
+
+#include <sys/types.h>
+#include <netinet/in.h>
+
+#ifdef WITH_OPENSSL
+#include <openssl/evp.h>
+#include <openssl/err.h>
+#include <openssl/pem.h>
+#endif
+
+#include "crypto_api.h"
+
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+#include <string.h>
+#include <resolv.h>
+#ifdef HAVE_UTIL_H
+#include <util.h>
+#endif /* HAVE_UTIL_H */
+
+#include "ssh2.h"
+#include "ssherr.h"
+#include "misc.h"
+#include "sshbuf.h"
+#include "cipher.h"
+#include "digest.h"
+#define SSHKEY_INTERNAL
+#include "sshkey.h"
+#include "sshkey-xmss.h"
+#include "match.h"
+
+#include "xmss_fast.h"
+
+#include "openbsd-compat/openssl-compat.h"
+
+/* openssh private key file format */
+#define MARK_BEGIN		"-----BEGIN OPENSSH PRIVATE KEY-----\n"
+#define MARK_END		"-----END OPENSSH PRIVATE KEY-----\n"
+#define MARK_BEGIN_LEN		(sizeof(MARK_BEGIN) - 1)
+#define MARK_END_LEN		(sizeof(MARK_END) - 1)
+#define KDFNAME			"bcrypt"
+#define AUTH_MAGIC		"openssh-key-v1"
+#define SALT_LEN		16
+#define DEFAULT_CIPHERNAME	"aes256-ctr"
+#define	DEFAULT_ROUNDS		16
+
+/* Version identification string for SSH v1 identity files. */
+#define LEGACY_BEGIN		"SSH PRIVATE KEY FILE FORMAT 1.1\n"
+
+int	sshkey_private_serialize_opt(const struct sshkey *key,
+    struct sshbuf *buf, enum sshkey_serialize_rep);
+static int sshkey_from_blob_internal(struct sshbuf *buf,
+    struct sshkey **keyp, int allow_cert);
+static int get_sigtype(const u_char *sig, size_t siglen, char **sigtypep);
+
+/* Supported key types */
+struct keytype {
+	const char *name;
+	const char *shortname;
+	const char *sigalg;
+	int type;
+	int nid;
+	int cert;
+	int sigonly;
+};
+static const struct keytype keytypes[] = {
+	{ "ssh-ed25519", "ED25519", NULL, KEY_ED25519, 0, 0, 0 },
+	{ "ssh-ed25519-cert-v01@openssh.com", "ED25519-CERT", NULL,
+	    KEY_ED25519_CERT, 0, 1, 0 },
+#ifdef WITH_XMSS
+	{ "ssh-xmss@openssh.com", "XMSS", NULL, KEY_XMSS, 0, 0, 0 },
+	{ "ssh-xmss-cert-v01@openssh.com", "XMSS-CERT", NULL,
+	    KEY_XMSS_CERT, 0, 1, 0 },
+#endif /* WITH_XMSS */
+#ifdef WITH_OPENSSL
+	{ "ssh-rsa", "RSA", NULL, KEY_RSA, 0, 0, 0 },
+	{ "rsa-sha2-256", "RSA", NULL, KEY_RSA, 0, 0, 1 },
+	{ "rsa-sha2-512", "RSA", NULL, KEY_RSA, 0, 0, 1 },
+	{ "ssh-dss", "DSA", NULL, KEY_DSA, 0, 0, 0 },
+# ifdef OPENSSL_HAS_ECC
+	{ "ecdsa-sha2-nistp256", "ECDSA", NULL,
+	    KEY_ECDSA, NID_X9_62_prime256v1, 0, 0 },
+	{ "ecdsa-sha2-nistp384", "ECDSA", NULL,
+	    KEY_ECDSA, NID_secp384r1, 0, 0 },
+#  ifdef OPENSSL_HAS_NISTP521
+	{ "ecdsa-sha2-nistp521", "ECDSA", NULL,
+	    KEY_ECDSA, NID_secp521r1, 0, 0 },
+#  endif /* OPENSSL_HAS_NISTP521 */
+# endif /* OPENSSL_HAS_ECC */
+	{ "ssh-rsa-cert-v01@openssh.com", "RSA-CERT", NULL,
+	    KEY_RSA_CERT, 0, 1, 0 },
+	{ "rsa-sha2-256-cert-v01@openssh.com", "RSA-CERT",
+	    "rsa-sha2-256", KEY_RSA_CERT, 0, 1, 1 },
+	{ "rsa-sha2-512-cert-v01@openssh.com", "RSA-CERT",
+	    "rsa-sha2-512", KEY_RSA_CERT, 0, 1, 1 },
+	{ "ssh-dss-cert-v01@openssh.com", "DSA-CERT", NULL,
+	    KEY_DSA_CERT, 0, 1, 0 },
+# ifdef OPENSSL_HAS_ECC
+	{ "ecdsa-sha2-nistp256-cert-v01@openssh.com", "ECDSA-CERT", NULL,
+	    KEY_ECDSA_CERT, NID_X9_62_prime256v1, 1, 0 },
+	{ "ecdsa-sha2-nistp384-cert-v01@openssh.com", "ECDSA-CERT", NULL,
+	    KEY_ECDSA_CERT, NID_secp384r1, 1, 0 },
+#  ifdef OPENSSL_HAS_NISTP521
+	{ "ecdsa-sha2-nistp521-cert-v01@openssh.com", "ECDSA-CERT", NULL,
+	   KEY_ECDSA_CERT, NID_secp521r1, 1, 0 },
+#  endif /* OPENSSL_HAS_NISTP521 */
+# endif /* OPENSSL_HAS_ECC */
+#endif /* WITH_OPENSSL */
+	{ NULL, NULL, NULL, -1, -1, 0, 0 }
+};
+
+const char *
+sshkey_type(const struct sshkey *k)
+{
+	const struct keytype *kt;
+
+	for (kt = keytypes; kt->type != -1; kt++) {
+		if (kt->type == k->type)
+			return kt->shortname;
+	}
+	return "unknown";
+}
+
+static const char *
+sshkey_ssh_name_from_type_nid(int type, int nid)
+{
+	const struct keytype *kt;
+
+	for (kt = keytypes; kt->type != -1; kt++) {
+		if (kt->type == type && (kt->nid == 0 || kt->nid == nid))
+			return kt->name;
+	}
+	return "ssh-unknown";
+}
+
+int
+sshkey_type_is_cert(int type)
+{
+	const struct keytype *kt;
+
+	for (kt = keytypes; kt->type != -1; kt++) {
+		if (kt->type == type)
+			return kt->cert;
+	}
+	return 0;
+}
+
+const char *
+sshkey_ssh_name(const struct sshkey *k)
+{
+	return sshkey_ssh_name_from_type_nid(k->type, k->ecdsa_nid);
+}
+
+const char *
+sshkey_ssh_name_plain(const struct sshkey *k)
+{
+	return sshkey_ssh_name_from_type_nid(sshkey_type_plain(k->type),
+	    k->ecdsa_nid);
+}
+
+int
+sshkey_type_from_name(const char *name)
+{
+	const struct keytype *kt;
+
+	for (kt = keytypes; kt->type != -1; kt++) {
+		/* Only allow shortname matches for plain key types */
+		if ((kt->name != NULL && strcmp(name, kt->name) == 0) ||
+		    (!kt->cert && strcasecmp(kt->shortname, name) == 0))
+			return kt->type;
+	}
+	return KEY_UNSPEC;
+}
+
+int
+sshkey_ecdsa_nid_from_name(const char *name)
+{
+	const struct keytype *kt;
+
+	for (kt = keytypes; kt->type != -1; kt++) {
+		if (kt->type != KEY_ECDSA && kt->type != KEY_ECDSA_CERT)
+			continue;
+		if (kt->name != NULL && strcmp(name, kt->name) == 0)
+			return kt->nid;
+	}
+	return -1;
+}
+
+char *
+sshkey_alg_list(int certs_only, int plain_only, int include_sigonly, char sep)
+{
+	char *tmp, *ret = NULL;
+	size_t nlen, rlen = 0;
+	const struct keytype *kt;
+
+	for (kt = keytypes; kt->type != -1; kt++) {
+		if (kt->name == NULL)
+			continue;
+		if (!include_sigonly && kt->sigonly)
+			continue;
+		if ((certs_only && !kt->cert) || (plain_only && kt->cert))
+			continue;
+		if (ret != NULL)
+			ret[rlen++] = sep;
+		nlen = strlen(kt->name);
+		if ((tmp = realloc(ret, rlen + nlen + 2)) == NULL) {
+			free(ret);
+			return NULL;
+		}
+		ret = tmp;
+		memcpy(ret + rlen, kt->name, nlen + 1);
+		rlen += nlen;
+	}
+	return ret;
+}
+
+int
+sshkey_names_valid2(const char *names, int allow_wildcard)
+{
+	char *s, *cp, *p;
+	const struct keytype *kt;
+	int type;
+
+	if (names == NULL || strcmp(names, "") == 0)
+		return 0;
+	if ((s = cp = strdup(names)) == NULL)
+		return 0;
+	for ((p = strsep(&cp, ",")); p && *p != '\0';
+	    (p = strsep(&cp, ","))) {
+		type = sshkey_type_from_name(p);
+		if (type == KEY_UNSPEC) {
+			if (allow_wildcard) {
+				/*
+				 * Try matching key types against the string.
+				 * If any has a positive or negative match then
+				 * the component is accepted.
+				 */
+				for (kt = keytypes; kt->type != -1; kt++) {
+					if (match_pattern_list(kt->name,
+					    p, 0) != 0)
+						break;
+				}
+				if (kt->type != -1)
+					continue;
+			}
+			free(s);
+			return 0;
+		}
+	}
+	free(s);
+	return 1;
+}
+
+u_int
+sshkey_size(const struct sshkey *k)
+{
+#ifdef WITH_OPENSSL
+	const BIGNUM *rsa_n, *dsa_p;
+#endif /* WITH_OPENSSL */
+
+	switch (k->type) {
+#ifdef WITH_OPENSSL
+	case KEY_RSA:
+	case KEY_RSA_CERT:
+		if (k->rsa == NULL)
+			return 0;
+		RSA_get0_key(k->rsa, &rsa_n, NULL, NULL);
+		return BN_num_bits(rsa_n);
+	case KEY_DSA:
+	case KEY_DSA_CERT:
+		if (k->dsa == NULL)
+			return 0;
+		DSA_get0_pqg(k->dsa, &dsa_p, NULL, NULL);
+		return BN_num_bits(dsa_p);
+	case KEY_ECDSA:
+	case KEY_ECDSA_CERT:
+		return sshkey_curve_nid_to_bits(k->ecdsa_nid);
+#endif /* WITH_OPENSSL */
+	case KEY_ED25519:
+	case KEY_ED25519_CERT:
+	case KEY_XMSS:
+	case KEY_XMSS_CERT:
+		return 256;	/* XXX */
+	}
+	return 0;
+}
+
+static int
+sshkey_type_is_valid_ca(int type)
+{
+	switch (type) {
+	case KEY_RSA:
+	case KEY_DSA:
+	case KEY_ECDSA:
+	case KEY_ED25519:
+	case KEY_XMSS:
+		return 1;
+	default:
+		return 0;
+	}
+}
+
+int
+sshkey_is_cert(const struct sshkey *k)
+{
+	if (k == NULL)
+		return 0;
+	return sshkey_type_is_cert(k->type);
+}
+
+/* Return the cert-less equivalent to a certified key type */
+int
+sshkey_type_plain(int type)
+{
+	switch (type) {
+	case KEY_RSA_CERT:
+		return KEY_RSA;
+	case KEY_DSA_CERT:
+		return KEY_DSA;
+	case KEY_ECDSA_CERT:
+		return KEY_ECDSA;
+	case KEY_ED25519_CERT:
+		return KEY_ED25519;
+	case KEY_XMSS_CERT:
+		return KEY_XMSS;
+	default:
+		return type;
+	}
+}
+
+#ifdef WITH_OPENSSL
+/* XXX: these are really begging for a table-driven approach */
+int
+sshkey_curve_name_to_nid(const char *name)
+{
+	if (strcmp(name, "nistp256") == 0)
+		return NID_X9_62_prime256v1;
+	else if (strcmp(name, "nistp384") == 0)
+		return NID_secp384r1;
+# ifdef OPENSSL_HAS_NISTP521
+	else if (strcmp(name, "nistp521") == 0)
+		return NID_secp521r1;
+# endif /* OPENSSL_HAS_NISTP521 */
+	else
+		return -1;
+}
+
+u_int
+sshkey_curve_nid_to_bits(int nid)
+{
+	switch (nid) {
+	case NID_X9_62_prime256v1:
+		return 256;
+	case NID_secp384r1:
+		return 384;
+# ifdef OPENSSL_HAS_NISTP521
+	case NID_secp521r1:
+		return 521;
+# endif /* OPENSSL_HAS_NISTP521 */
+	default:
+		return 0;
+	}
+}
+
+int
+sshkey_ecdsa_bits_to_nid(int bits)
+{
+	switch (bits) {
+	case 256:
+		return NID_X9_62_prime256v1;
+	case 384:
+		return NID_secp384r1;
+# ifdef OPENSSL_HAS_NISTP521
+	case 521:
+		return NID_secp521r1;
+# endif /* OPENSSL_HAS_NISTP521 */
+	default:
+		return -1;
+	}
+}
+
+const char *
+sshkey_curve_nid_to_name(int nid)
+{
+	switch (nid) {
+	case NID_X9_62_prime256v1:
+		return "nistp256";
+	case NID_secp384r1:
+		return "nistp384";
+# ifdef OPENSSL_HAS_NISTP521
+	case NID_secp521r1:
+		return "nistp521";
+# endif /* OPENSSL_HAS_NISTP521 */
+	default:
+		return NULL;
+	}
+}
+
+int
+sshkey_ec_nid_to_hash_alg(int nid)
+{
+	int kbits = sshkey_curve_nid_to_bits(nid);
+
+	if (kbits <= 0)
+		return -1;
+
+	/* RFC5656 section 6.2.1 */
+	if (kbits <= 256)
+		return SSH_DIGEST_SHA256;
+	else if (kbits <= 384)
+		return SSH_DIGEST_SHA384;
+	else
+		return SSH_DIGEST_SHA512;
+}
+#endif /* WITH_OPENSSL */
+
+static void
+cert_free(struct sshkey_cert *cert)
+{
+	u_int i;
+
+	if (cert == NULL)
+		return;
+	sshbuf_free(cert->certblob);
+	sshbuf_free(cert->critical);
+	sshbuf_free(cert->extensions);
+	free(cert->key_id);
+	for (i = 0; i < cert->nprincipals; i++)
+		free(cert->principals[i]);
+	free(cert->principals);
+	sshkey_free(cert->signature_key);
+	free(cert->signature_type);
+	freezero(cert, sizeof(*cert));
+}
+
+static struct sshkey_cert *
+cert_new(void)
+{
+	struct sshkey_cert *cert;
+
+	if ((cert = calloc(1, sizeof(*cert))) == NULL)
+		return NULL;
+	if ((cert->certblob = sshbuf_new()) == NULL ||
+	    (cert->critical = sshbuf_new()) == NULL ||
+	    (cert->extensions = sshbuf_new()) == NULL) {
+		cert_free(cert);
+		return NULL;
+	}
+	cert->key_id = NULL;
+	cert->principals = NULL;
+	cert->signature_key = NULL;
+	cert->signature_type = NULL;
+	return cert;
+}
+
+struct sshkey *
+sshkey_new(int type)
+{
+	struct sshkey *k;
+#ifdef WITH_OPENSSL
+	RSA *rsa;
+	DSA *dsa;
+#endif /* WITH_OPENSSL */
+
+	if ((k = calloc(1, sizeof(*k))) == NULL)
+		return NULL;
+	k->type = type;
+	k->ecdsa = NULL;
+	k->ecdsa_nid = -1;
+	k->dsa = NULL;
+	k->rsa = NULL;
+	k->cert = NULL;
+	k->ed25519_sk = NULL;
+	k->ed25519_pk = NULL;
+	k->xmss_sk = NULL;
+	k->xmss_pk = NULL;
+	switch (k->type) {
+#ifdef WITH_OPENSSL
+	case KEY_RSA:
+	case KEY_RSA_CERT:
+		if ((rsa = RSA_new()) == NULL) {
+			free(k);
+			return NULL;
+		}
+		k->rsa = rsa;
+		break;
+	case KEY_DSA:
+	case KEY_DSA_CERT:
+		if ((dsa = DSA_new()) == NULL) {
+			free(k);
+			return NULL;
+		}
+		k->dsa = dsa;
+		break;
+	case KEY_ECDSA:
+	case KEY_ECDSA_CERT:
+		/* Cannot do anything until we know the group */
+		break;
+#endif /* WITH_OPENSSL */
+	case KEY_ED25519:
+	case KEY_ED25519_CERT:
+	case KEY_XMSS:
+	case KEY_XMSS_CERT:
+		/* no need to prealloc */
+		break;
+	case KEY_UNSPEC:
+		break;
+	default:
+		free(k);
+		return NULL;
+	}
+
+	if (sshkey_is_cert(k)) {
+		if ((k->cert = cert_new()) == NULL) {
+			sshkey_free(k);
+			return NULL;
+		}
+	}
+
+	return k;
+}
+
+void
+sshkey_free(struct sshkey *k)
+{
+	if (k == NULL)
+		return;
+	switch (k->type) {
+#ifdef WITH_OPENSSL
+	case KEY_RSA:
+	case KEY_RSA_CERT:
+		RSA_free(k->rsa);
+		k->rsa = NULL;
+		break;
+	case KEY_DSA:
+	case KEY_DSA_CERT:
+		DSA_free(k->dsa);
+		k->dsa = NULL;
+		break;
+# ifdef OPENSSL_HAS_ECC
+	case KEY_ECDSA:
+	case KEY_ECDSA_CERT:
+		EC_KEY_free(k->ecdsa);
+		k->ecdsa = NULL;
+		break;
+# endif /* OPENSSL_HAS_ECC */
+#endif /* WITH_OPENSSL */
+	case KEY_ED25519:
+	case KEY_ED25519_CERT:
+		freezero(k->ed25519_pk, ED25519_PK_SZ);
+		k->ed25519_pk = NULL;
+		freezero(k->ed25519_sk, ED25519_SK_SZ);
+		k->ed25519_sk = NULL;
+		break;
+#ifdef WITH_XMSS
+	case KEY_XMSS:
+	case KEY_XMSS_CERT:
+		freezero(k->xmss_pk, sshkey_xmss_pklen(k));
+		k->xmss_pk = NULL;
+		freezero(k->xmss_sk, sshkey_xmss_sklen(k));
+		k->xmss_sk = NULL;
+		sshkey_xmss_free_state(k);
+		free(k->xmss_name);
+		k->xmss_name = NULL;
+		free(k->xmss_filename);
+		k->xmss_filename = NULL;
+		break;
+#endif /* WITH_XMSS */
+	case KEY_UNSPEC:
+		break;
+	default:
+		break;
+	}
+	if (sshkey_is_cert(k))
+		cert_free(k->cert);
+	freezero(k, sizeof(*k));
+}
+
+static int
+cert_compare(struct sshkey_cert *a, struct sshkey_cert *b)
+{
+	if (a == NULL && b == NULL)
+		return 1;
+	if (a == NULL || b == NULL)
+		return 0;
+	if (sshbuf_len(a->certblob) != sshbuf_len(b->certblob))
+		return 0;
+	if (timingsafe_bcmp(sshbuf_ptr(a->certblob), sshbuf_ptr(b->certblob),
+	    sshbuf_len(a->certblob)) != 0)
+		return 0;
+	return 1;
+}
+
+/*
+ * Compare public portions of key only, allowing comparisons between
+ * certificates and plain keys too.
+ */
+int
+sshkey_equal_public(const struct sshkey *a, const struct sshkey *b)
+{
+#if defined(WITH_OPENSSL)
+	const BIGNUM *rsa_e_a, *rsa_n_a;
+	const BIGNUM *rsa_e_b, *rsa_n_b;
+	const BIGNUM *dsa_p_a, *dsa_q_a, *dsa_g_a, *dsa_pub_key_a;
+	const BIGNUM *dsa_p_b, *dsa_q_b, *dsa_g_b, *dsa_pub_key_b;
+# if defined(OPENSSL_HAS_ECC)
+	BN_CTX *bnctx;
+# endif /* OPENSSL_HAS_ECC */
+#endif /* WITH_OPENSSL */
+
+	if (a == NULL || b == NULL ||
+	    sshkey_type_plain(a->type) != sshkey_type_plain(b->type))
+		return 0;
+
+	switch (a->type) {
+#ifdef WITH_OPENSSL
+	case KEY_RSA_CERT:
+	case KEY_RSA:
+		if (a->rsa == NULL || b->rsa == NULL)
+			return 0;
+		RSA_get0_key(a->rsa, &rsa_n_a, &rsa_e_a, NULL);
+		RSA_get0_key(b->rsa, &rsa_n_b, &rsa_e_b, NULL);
+		return BN_cmp(rsa_e_a, rsa_e_b) == 0 &&
+		    BN_cmp(rsa_n_a, rsa_n_b) == 0;
+	case KEY_DSA_CERT:
+	case KEY_DSA:
+		if (a->dsa == NULL || b->dsa == NULL)
+			return 0;
+		DSA_get0_pqg(a->dsa, &dsa_p_a, &dsa_q_a, &dsa_g_a);
+		DSA_get0_pqg(b->dsa, &dsa_p_b, &dsa_q_b, &dsa_g_b);
+		DSA_get0_key(a->dsa, &dsa_pub_key_a, NULL);
+		DSA_get0_key(b->dsa, &dsa_pub_key_b, NULL);
+		return BN_cmp(dsa_p_a, dsa_p_b) == 0 &&
+		    BN_cmp(dsa_q_a, dsa_q_b) == 0 &&
+		    BN_cmp(dsa_g_a, dsa_g_b) == 0 &&
+		    BN_cmp(dsa_pub_key_a, dsa_pub_key_b) == 0;
+# ifdef OPENSSL_HAS_ECC
+	case KEY_ECDSA_CERT:
+	case KEY_ECDSA:
+		if (a->ecdsa == NULL || b->ecdsa == NULL ||
+		    EC_KEY_get0_public_key(a->ecdsa) == NULL ||
+		    EC_KEY_get0_public_key(b->ecdsa) == NULL)
+			return 0;
+		if ((bnctx = BN_CTX_new()) == NULL)
+			return 0;
+		if (EC_GROUP_cmp(EC_KEY_get0_group(a->ecdsa),
+		    EC_KEY_get0_group(b->ecdsa), bnctx) != 0 ||
+		    EC_POINT_cmp(EC_KEY_get0_group(a->ecdsa),
+		    EC_KEY_get0_public_key(a->ecdsa),
+		    EC_KEY_get0_public_key(b->ecdsa), bnctx) != 0) {
+			BN_CTX_free(bnctx);
+			return 0;
+		}
+		BN_CTX_free(bnctx);
+		return 1;
+# endif /* OPENSSL_HAS_ECC */
+#endif /* WITH_OPENSSL */
+	case KEY_ED25519:
+	case KEY_ED25519_CERT:
+		return a->ed25519_pk != NULL && b->ed25519_pk != NULL &&
+		    memcmp(a->ed25519_pk, b->ed25519_pk, ED25519_PK_SZ) == 0;
+#ifdef WITH_XMSS
+	case KEY_XMSS:
+	case KEY_XMSS_CERT:
+		return a->xmss_pk != NULL && b->xmss_pk != NULL &&
+		    sshkey_xmss_pklen(a) == sshkey_xmss_pklen(b) &&
+		    memcmp(a->xmss_pk, b->xmss_pk, sshkey_xmss_pklen(a)) == 0;
+#endif /* WITH_XMSS */
+	default:
+		return 0;
+	}
+	/* NOTREACHED */
+}
+
+int
+sshkey_equal(const struct sshkey *a, const struct sshkey *b)
+{
+	if (a == NULL || b == NULL || a->type != b->type)
+		return 0;
+	if (sshkey_is_cert(a)) {
+		if (!cert_compare(a->cert, b->cert))
+			return 0;
+	}
+	return sshkey_equal_public(a, b);
+}
+
+static int
+to_blob_buf(const struct sshkey *key, struct sshbuf *b, int force_plain,
+  enum sshkey_serialize_rep opts)
+{
+	int type, ret = SSH_ERR_INTERNAL_ERROR;
+	const char *typename;
+#ifdef WITH_OPENSSL
+	const BIGNUM *rsa_n, *rsa_e, *dsa_p, *dsa_q, *dsa_g, *dsa_pub_key;
+#endif /* WITH_OPENSSL */
+
+	if (key == NULL)
+		return SSH_ERR_INVALID_ARGUMENT;
+
+	if (sshkey_is_cert(key)) {
+		if (key->cert == NULL)
+			return SSH_ERR_EXPECTED_CERT;
+		if (sshbuf_len(key->cert->certblob) == 0)
+			return SSH_ERR_KEY_LACKS_CERTBLOB;
+	}
+	type = force_plain ? sshkey_type_plain(key->type) : key->type;
+	typename = sshkey_ssh_name_from_type_nid(type, key->ecdsa_nid);
+
+	switch (type) {
+#ifdef WITH_OPENSSL
+	case KEY_DSA_CERT:
+	case KEY_ECDSA_CERT:
+	case KEY_RSA_CERT:
+#endif /* WITH_OPENSSL */
+	case KEY_ED25519_CERT:
+#ifdef WITH_XMSS
+	case KEY_XMSS_CERT:
+#endif /* WITH_XMSS */
+		/* Use the existing blob */
+		/* XXX modified flag? */
+		if ((ret = sshbuf_putb(b, key->cert->certblob)) != 0)
+			return ret;
+		break;
+#ifdef WITH_OPENSSL
+	case KEY_DSA:
+		if (key->dsa == NULL)
+			return SSH_ERR_INVALID_ARGUMENT;
+		DSA_get0_pqg(key->dsa, &dsa_p, &dsa_q, &dsa_g);
+		DSA_get0_key(key->dsa, &dsa_pub_key, NULL);
+		if ((ret = sshbuf_put_cstring(b, typename)) != 0 ||
+		    (ret = sshbuf_put_bignum2(b, dsa_p)) != 0 ||
+		    (ret = sshbuf_put_bignum2(b, dsa_q)) != 0 ||
+		    (ret = sshbuf_put_bignum2(b, dsa_g)) != 0 ||
+		    (ret = sshbuf_put_bignum2(b, dsa_pub_key)) != 0)
+			return ret;
+		break;
+# ifdef OPENSSL_HAS_ECC
+	case KEY_ECDSA:
+		if (key->ecdsa == NULL)
+			return SSH_ERR_INVALID_ARGUMENT;
+		if ((ret = sshbuf_put_cstring(b, typename)) != 0 ||
+		    (ret = sshbuf_put_cstring(b,
+		    sshkey_curve_nid_to_name(key->ecdsa_nid))) != 0 ||
+		    (ret = sshbuf_put_eckey(b, key->ecdsa)) != 0)
+			return ret;
+		break;
+# endif
+	case KEY_RSA:
+		if (key->rsa == NULL)
+			return SSH_ERR_INVALID_ARGUMENT;
+		RSA_get0_key(key->rsa, &rsa_n, &rsa_e, NULL);
+		if ((ret = sshbuf_put_cstring(b, typename)) != 0 ||
+		    (ret = sshbuf_put_bignum2(b, rsa_e)) != 0 ||
+		    (ret = sshbuf_put_bignum2(b, rsa_n)) != 0)
+			return ret;
+		break;
+#endif /* WITH_OPENSSL */
+	case KEY_ED25519:
+		if (key->ed25519_pk == NULL)
+			return SSH_ERR_INVALID_ARGUMENT;
+		if ((ret = sshbuf_put_cstring(b, typename)) != 0 ||
+		    (ret = sshbuf_put_string(b,
+		    key->ed25519_pk, ED25519_PK_SZ)) != 0)
+			return ret;
+		break;
+#ifdef WITH_XMSS
+	case KEY_XMSS:
+		if (key->xmss_name == NULL || key->xmss_pk == NULL ||
+		    sshkey_xmss_pklen(key) == 0)
+			return SSH_ERR_INVALID_ARGUMENT;
+		if ((ret = sshbuf_put_cstring(b, typename)) != 0 ||
+		    (ret = sshbuf_put_cstring(b, key->xmss_name)) != 0 ||
+		    (ret = sshbuf_put_string(b,
+		    key->xmss_pk, sshkey_xmss_pklen(key))) != 0 ||
+		    (ret = sshkey_xmss_serialize_pk_info(key, b, opts)) != 0)
+			return ret;
+		break;
+#endif /* WITH_XMSS */
+	default:
+		return SSH_ERR_KEY_TYPE_UNKNOWN;
+	}
+	return 0;
+}
+
+int
+sshkey_putb(const struct sshkey *key, struct sshbuf *b)
+{
+	return to_blob_buf(key, b, 0, SSHKEY_SERIALIZE_DEFAULT);
+}
+
+int
+sshkey_puts_opts(const struct sshkey *key, struct sshbuf *b,
+    enum sshkey_serialize_rep opts)
+{
+	struct sshbuf *tmp;
+	int r;
+
+	if ((tmp = sshbuf_new()) == NULL)
+		return SSH_ERR_ALLOC_FAIL;
+	r = to_blob_buf(key, tmp, 0, opts);
+	if (r == 0)
+		r = sshbuf_put_stringb(b, tmp);
+	sshbuf_free(tmp);
+	return r;
+}
+
+int
+sshkey_puts(const struct sshkey *key, struct sshbuf *b)
+{
+	return sshkey_puts_opts(key, b, SSHKEY_SERIALIZE_DEFAULT);
+}
+
+int
+sshkey_putb_plain(const struct sshkey *key, struct sshbuf *b)
+{
+	return to_blob_buf(key, b, 1, SSHKEY_SERIALIZE_DEFAULT);
+}
+
+static int
+to_blob(const struct sshkey *key, u_char **blobp, size_t *lenp, int force_plain,
+    enum sshkey_serialize_rep opts)
+{
+	int ret = SSH_ERR_INTERNAL_ERROR;
+	size_t len;
+	struct sshbuf *b = NULL;
+
+	if (lenp != NULL)
+		*lenp = 0;
+	if (blobp != NULL)
+		*blobp = NULL;
+	if ((b = sshbuf_new()) == NULL)
+		return SSH_ERR_ALLOC_FAIL;
+	if ((ret = to_blob_buf(key, b, force_plain, opts)) != 0)
+		goto out;
+	len = sshbuf_len(b);
+	if (lenp != NULL)
+		*lenp = len;
+	if (blobp != NULL) {
+		if ((*blobp = malloc(len)) == NULL) {
+			ret = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		memcpy(*blobp, sshbuf_ptr(b), len);
+	}
+	ret = 0;
+ out:
+	sshbuf_free(b);
+	return ret;
+}
+
+int
+sshkey_to_blob(const struct sshkey *key, u_char **blobp, size_t *lenp)
+{
+	return to_blob(key, blobp, lenp, 0, SSHKEY_SERIALIZE_DEFAULT);
+}
+
+int
+sshkey_plain_to_blob(const struct sshkey *key, u_char **blobp, size_t *lenp)
+{
+	return to_blob(key, blobp, lenp, 1, SSHKEY_SERIALIZE_DEFAULT);
+}
+
+int
+sshkey_fingerprint_raw(const struct sshkey *k, int dgst_alg,
+    u_char **retp, size_t *lenp)
+{
+	u_char *blob = NULL, *ret = NULL;
+	size_t blob_len = 0;
+	int r = SSH_ERR_INTERNAL_ERROR;
+
+	if (retp != NULL)
+		*retp = NULL;
+	if (lenp != NULL)
+		*lenp = 0;
+	if (ssh_digest_bytes(dgst_alg) == 0) {
+		r = SSH_ERR_INVALID_ARGUMENT;
+		goto out;
+	}
+	if ((r = to_blob(k, &blob, &blob_len, 1, SSHKEY_SERIALIZE_DEFAULT))
+	    != 0)
+		goto out;
+	if ((ret = calloc(1, SSH_DIGEST_MAX_LENGTH)) == NULL) {
+		r = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+	if ((r = ssh_digest_memory(dgst_alg, blob, blob_len,
+	    ret, SSH_DIGEST_MAX_LENGTH)) != 0)
+		goto out;
+	/* success */
+	if (retp != NULL) {
+		*retp = ret;
+		ret = NULL;
+	}
+	if (lenp != NULL)
+		*lenp = ssh_digest_bytes(dgst_alg);
+	r = 0;
+ out:
+	free(ret);
+	if (blob != NULL) {
+		explicit_bzero(blob, blob_len);
+		free(blob);
+	}
+	return r;
+}
+
+static char *
+fingerprint_b64(const char *alg, u_char *dgst_raw, size_t dgst_raw_len)
+{
+	char *ret;
+	size_t plen = strlen(alg) + 1;
+	size_t rlen = ((dgst_raw_len + 2) / 3) * 4 + plen + 1;
+	int r;
+
+	if (dgst_raw_len > 65536 || (ret = calloc(1, rlen)) == NULL)
+		return NULL;
+	strlcpy(ret, alg, rlen);
+	strlcat(ret, ":", rlen);
+	if (dgst_raw_len == 0)
+		return ret;
+	if ((r = b64_ntop(dgst_raw, dgst_raw_len,
+	    ret + plen, rlen - plen)) == -1) {
+		freezero(ret, rlen);
+		return NULL;
+	}
+	/* Trim padding characters from end */
+	ret[strcspn(ret, "=")] = '\0';
+	return ret;
+}
+
+static char *
+fingerprint_hex(const char *alg, u_char *dgst_raw, size_t dgst_raw_len)
+{
+	char *retval, hex[5];
+	size_t i, rlen = dgst_raw_len * 3 + strlen(alg) + 2;
+
+	if (dgst_raw_len > 65536 || (retval = calloc(1, rlen)) == NULL)
+		return NULL;
+	strlcpy(retval, alg, rlen);
+	strlcat(retval, ":", rlen);
+	for (i = 0; i < dgst_raw_len; i++) {
+		snprintf(hex, sizeof(hex), "%s%02x",
+		    i > 0 ? ":" : "", dgst_raw[i]);
+		strlcat(retval, hex, rlen);
+	}
+	return retval;
+}
+
+static char *
+fingerprint_bubblebabble(u_char *dgst_raw, size_t dgst_raw_len)
+{
+	char vowels[] = { 'a', 'e', 'i', 'o', 'u', 'y' };
+	char consonants[] = { 'b', 'c', 'd', 'f', 'g', 'h', 'k', 'l', 'm',
+	    'n', 'p', 'r', 's', 't', 'v', 'z', 'x' };
+	u_int i, j = 0, rounds, seed = 1;
+	char *retval;
+
+	rounds = (dgst_raw_len / 2) + 1;
+	if ((retval = calloc(rounds, 6)) == NULL)
+		return NULL;
+	retval[j++] = 'x';
+	for (i = 0; i < rounds; i++) {
+		u_int idx0, idx1, idx2, idx3, idx4;
+		if ((i + 1 < rounds) || (dgst_raw_len % 2 != 0)) {
+			idx0 = (((((u_int)(dgst_raw[2 * i])) >> 6) & 3) +
+			    seed) % 6;
+			idx1 = (((u_int)(dgst_raw[2 * i])) >> 2) & 15;
+			idx2 = ((((u_int)(dgst_raw[2 * i])) & 3) +
+			    (seed / 6)) % 6;
+			retval[j++] = vowels[idx0];
+			retval[j++] = consonants[idx1];
+			retval[j++] = vowels[idx2];
+			if ((i + 1) < rounds) {
+				idx3 = (((u_int)(dgst_raw[(2 * i) + 1])) >> 4) & 15;
+				idx4 = (((u_int)(dgst_raw[(2 * i) + 1]))) & 15;
+				retval[j++] = consonants[idx3];
+				retval[j++] = '-';
+				retval[j++] = consonants[idx4];
+				seed = ((seed * 5) +
+				    ((((u_int)(dgst_raw[2 * i])) * 7) +
+				    ((u_int)(dgst_raw[(2 * i) + 1])))) % 36;
+			}
+		} else {
+			idx0 = seed % 6;
+			idx1 = 16;
+			idx2 = seed / 6;
+			retval[j++] = vowels[idx0];
+			retval[j++] = consonants[idx1];
+			retval[j++] = vowels[idx2];
+		}
+	}
+	retval[j++] = 'x';
+	retval[j++] = '\0';
+	return retval;
+}
+
+/*
+ * Draw an ASCII-Art representing the fingerprint so human brain can
+ * profit from its built-in pattern recognition ability.
+ * This technique is called "random art" and can be found in some
+ * scientific publications like this original paper:
+ *
+ * "Hash Visualization: a New Technique to improve Real-World Security",
+ * Perrig A. and Song D., 1999, International Workshop on Cryptographic
+ * Techniques and E-Commerce (CrypTEC '99)
+ * sparrow.ece.cmu.edu/~adrian/projects/validation/validation.pdf
+ *
+ * The subject came up in a talk by Dan Kaminsky, too.
+ *
+ * If you see the picture is different, the key is different.
+ * If the picture looks the same, you still know nothing.
+ *
+ * The algorithm used here is a worm crawling over a discrete plane,
+ * leaving a trace (augmenting the field) everywhere it goes.
+ * Movement is taken from dgst_raw 2bit-wise.  Bumping into walls
+ * makes the respective movement vector be ignored for this turn.
+ * Graphs are not unambiguous, because circles in graphs can be
+ * walked in either direction.
+ */
+
+/*
+ * Field sizes for the random art.  Have to be odd, so the starting point
+ * can be in the exact middle of the picture, and FLDBASE should be >=8 .
+ * Else pictures would be too dense, and drawing the frame would
+ * fail, too, because the key type would not fit in anymore.
+ */
+#define	FLDBASE		8
+#define	FLDSIZE_Y	(FLDBASE + 1)
+#define	FLDSIZE_X	(FLDBASE * 2 + 1)
+static char *
+fingerprint_randomart(const char *alg, u_char *dgst_raw, size_t dgst_raw_len,
+    const struct sshkey *k)
+{
+	/*
+	 * Chars to be used after each other every time the worm
+	 * intersects with itself.  Matter of taste.
+	 */
+	char	*augmentation_string = " .o+=*BOX@%&#/^SE";
+	char	*retval, *p, title[FLDSIZE_X], hash[FLDSIZE_X];
+	u_char	 field[FLDSIZE_X][FLDSIZE_Y];
+	size_t	 i, tlen, hlen;
+	u_int	 b;
+	int	 x, y, r;
+	size_t	 len = strlen(augmentation_string) - 1;
+
+	if ((retval = calloc((FLDSIZE_X + 3), (FLDSIZE_Y + 2))) == NULL)
+		return NULL;
+
+	/* initialize field */
+	memset(field, 0, FLDSIZE_X * FLDSIZE_Y * sizeof(char));
+	x = FLDSIZE_X / 2;
+	y = FLDSIZE_Y / 2;
+
+	/* process raw key */
+	for (i = 0; i < dgst_raw_len; i++) {
+		int input;
+		/* each byte conveys four 2-bit move commands */
+		input = dgst_raw[i];
+		for (b = 0; b < 4; b++) {
+			/* evaluate 2 bit, rest is shifted later */
+			x += (input & 0x1) ? 1 : -1;
+			y += (input & 0x2) ? 1 : -1;
+
+			/* assure we are still in bounds */
+			x = MAXIMUM(x, 0);
+			y = MAXIMUM(y, 0);
+			x = MINIMUM(x, FLDSIZE_X - 1);
+			y = MINIMUM(y, FLDSIZE_Y - 1);
+
+			/* augment the field */
+			if (field[x][y] < len - 2)
+				field[x][y]++;
+			input = input >> 2;
+		}
+	}
+
+	/* mark starting point and end point*/
+	field[FLDSIZE_X / 2][FLDSIZE_Y / 2] = len - 1;
+	field[x][y] = len;
+
+	/* assemble title */
+	r = snprintf(title, sizeof(title), "[%s %u]",
+		sshkey_type(k), sshkey_size(k));
+	/* If [type size] won't fit, then try [type]; fits "[ED25519-CERT]" */
+	if (r < 0 || r > (int)sizeof(title))
+		r = snprintf(title, sizeof(title), "[%s]", sshkey_type(k));
+	tlen = (r <= 0) ? 0 : strlen(title);
+
+	/* assemble hash ID. */
+	r = snprintf(hash, sizeof(hash), "[%s]", alg);
+	hlen = (r <= 0) ? 0 : strlen(hash);
+
+	/* output upper border */
+	p = retval;
+	*p++ = '+';
+	for (i = 0; i < (FLDSIZE_X - tlen) / 2; i++)
+		*p++ = '-';
+	memcpy(p, title, tlen);
+	p += tlen;
+	for (i += tlen; i < FLDSIZE_X; i++)
+		*p++ = '-';
+	*p++ = '+';
+	*p++ = '\n';
+
+	/* output content */
+	for (y = 0; y < FLDSIZE_Y; y++) {
+		*p++ = '|';
+		for (x = 0; x < FLDSIZE_X; x++)
+			*p++ = augmentation_string[MINIMUM(field[x][y], len)];
+		*p++ = '|';
+		*p++ = '\n';
+	}
+
+	/* output lower border */
+	*p++ = '+';
+	for (i = 0; i < (FLDSIZE_X - hlen) / 2; i++)
+		*p++ = '-';
+	memcpy(p, hash, hlen);
+	p += hlen;
+	for (i += hlen; i < FLDSIZE_X; i++)
+		*p++ = '-';
+	*p++ = '+';
+
+	return retval;
+}
+
+char *
+sshkey_fingerprint(const struct sshkey *k, int dgst_alg,
+    enum sshkey_fp_rep dgst_rep)
+{
+	char *retval = NULL;
+	u_char *dgst_raw;
+	size_t dgst_raw_len;
+
+	if (sshkey_fingerprint_raw(k, dgst_alg, &dgst_raw, &dgst_raw_len) != 0)
+		return NULL;
+	switch (dgst_rep) {
+	case SSH_FP_DEFAULT:
+		if (dgst_alg == SSH_DIGEST_MD5) {
+			retval = fingerprint_hex(ssh_digest_alg_name(dgst_alg),
+			    dgst_raw, dgst_raw_len);
+		} else {
+			retval = fingerprint_b64(ssh_digest_alg_name(dgst_alg),
+			    dgst_raw, dgst_raw_len);
+		}
+		break;
+	case SSH_FP_HEX:
+		retval = fingerprint_hex(ssh_digest_alg_name(dgst_alg),
+		    dgst_raw, dgst_raw_len);
+		break;
+	case SSH_FP_BASE64:
+		retval = fingerprint_b64(ssh_digest_alg_name(dgst_alg),
+		    dgst_raw, dgst_raw_len);
+		break;
+	case SSH_FP_BUBBLEBABBLE:
+		retval = fingerprint_bubblebabble(dgst_raw, dgst_raw_len);
+		break;
+	case SSH_FP_RANDOMART:
+		retval = fingerprint_randomart(ssh_digest_alg_name(dgst_alg),
+		    dgst_raw, dgst_raw_len, k);
+		break;
+	default:
+		explicit_bzero(dgst_raw, dgst_raw_len);
+		free(dgst_raw);
+		return NULL;
+	}
+	explicit_bzero(dgst_raw, dgst_raw_len);
+	free(dgst_raw);
+	return retval;
+}
+
+static int
+peek_type_nid(const char *s, size_t l, int *nid)
+{
+	const struct keytype *kt;
+
+	for (kt = keytypes; kt->type != -1; kt++) {
+		if (kt->name == NULL || strlen(kt->name) != l)
+			continue;
+		if (memcmp(s, kt->name, l) == 0) {
+			*nid = -1;
+			if (kt->type == KEY_ECDSA || kt->type == KEY_ECDSA_CERT)
+				*nid = kt->nid;
+			return kt->type;
+		}
+	}
+	return KEY_UNSPEC;
+}
+
+/* XXX this can now be made const char * */
+int
+sshkey_read(struct sshkey *ret, char **cpp)
+{
+	struct sshkey *k;
+	char *cp, *blobcopy;
+	size_t space;
+	int r, type, curve_nid = -1;
+	struct sshbuf *blob;
+
+	if (ret == NULL)
+		return SSH_ERR_INVALID_ARGUMENT;
+
+	switch (ret->type) {
+	case KEY_UNSPEC:
+	case KEY_RSA:
+	case KEY_DSA:
+	case KEY_ECDSA:
+	case KEY_ED25519:
+	case KEY_DSA_CERT:
+	case KEY_ECDSA_CERT:
+	case KEY_RSA_CERT:
+	case KEY_ED25519_CERT:
+#ifdef WITH_XMSS
+	case KEY_XMSS:
+	case KEY_XMSS_CERT:
+#endif /* WITH_XMSS */
+		break; /* ok */
+	default:
+		return SSH_ERR_INVALID_ARGUMENT;
+	}
+
+	/* Decode type */
+	cp = *cpp;
+	space = strcspn(cp, " \t");
+	if (space == strlen(cp))
+		return SSH_ERR_INVALID_FORMAT;
+	if ((type = peek_type_nid(cp, space, &curve_nid)) == KEY_UNSPEC)
+		return SSH_ERR_INVALID_FORMAT;
+
+	/* skip whitespace */
+	for (cp += space; *cp == ' ' || *cp == '\t'; cp++)
+		;
+	if (*cp == '\0')
+		return SSH_ERR_INVALID_FORMAT;
+	if (ret->type != KEY_UNSPEC && ret->type != type)
+		return SSH_ERR_KEY_TYPE_MISMATCH;
+	if ((blob = sshbuf_new()) == NULL)
+		return SSH_ERR_ALLOC_FAIL;
+
+	/* find end of keyblob and decode */
+	space = strcspn(cp, " \t");
+	if ((blobcopy = strndup(cp, space)) == NULL) {
+		sshbuf_free(blob);
+		return SSH_ERR_ALLOC_FAIL;
+	}
+	if ((r = sshbuf_b64tod(blob, blobcopy)) != 0) {
+		free(blobcopy);
+		sshbuf_free(blob);
+		return r;
+	}
+	free(blobcopy);
+	if ((r = sshkey_fromb(blob, &k)) != 0) {
+		sshbuf_free(blob);
+		return r;
+	}
+	sshbuf_free(blob);
+
+	/* skip whitespace and leave cp at start of comment */
+	for (cp += space; *cp == ' ' || *cp == '\t'; cp++)
+		;
+
+	/* ensure type of blob matches type at start of line */
+	if (k->type != type) {
+		sshkey_free(k);
+		return SSH_ERR_KEY_TYPE_MISMATCH;
+	}
+	if (sshkey_type_plain(type) == KEY_ECDSA && curve_nid != k->ecdsa_nid) {
+		sshkey_free(k);
+		return SSH_ERR_EC_CURVE_MISMATCH;
+	}
+
+	/* Fill in ret from parsed key */
+	ret->type = type;
+	if (sshkey_is_cert(ret)) {
+		if (!sshkey_is_cert(k)) {
+			sshkey_free(k);
+			return SSH_ERR_EXPECTED_CERT;
+		}
+		if (ret->cert != NULL)
+			cert_free(ret->cert);
+		ret->cert = k->cert;
+		k->cert = NULL;
+	}
+	switch (sshkey_type_plain(ret->type)) {
+#ifdef WITH_OPENSSL
+	case KEY_RSA:
+		RSA_free(ret->rsa);
+		ret->rsa = k->rsa;
+		k->rsa = NULL;
+#ifdef DEBUG_PK
+		RSA_print_fp(stderr, ret->rsa, 8);
+#endif
+		break;
+	case KEY_DSA:
+		DSA_free(ret->dsa);
+		ret->dsa = k->dsa;
+		k->dsa = NULL;
+#ifdef DEBUG_PK
+		DSA_print_fp(stderr, ret->dsa, 8);
+#endif
+		break;
+# ifdef OPENSSL_HAS_ECC
+	case KEY_ECDSA:
+		EC_KEY_free(ret->ecdsa);
+		ret->ecdsa = k->ecdsa;
+		ret->ecdsa_nid = k->ecdsa_nid;
+		k->ecdsa = NULL;
+		k->ecdsa_nid = -1;
+#ifdef DEBUG_PK
+		sshkey_dump_ec_key(ret->ecdsa);
+#endif
+		break;
+# endif /* OPENSSL_HAS_ECC */
+#endif /* WITH_OPENSSL */
+	case KEY_ED25519:
+		freezero(ret->ed25519_pk, ED25519_PK_SZ);
+		ret->ed25519_pk = k->ed25519_pk;
+		k->ed25519_pk = NULL;
+#ifdef DEBUG_PK
+		/* XXX */
+#endif
+		break;
+#ifdef WITH_XMSS
+	case KEY_XMSS:
+		free(ret->xmss_pk);
+		ret->xmss_pk = k->xmss_pk;
+		k->xmss_pk = NULL;
+		free(ret->xmss_state);
+		ret->xmss_state = k->xmss_state;
+		k->xmss_state = NULL;
+		free(ret->xmss_name);
+		ret->xmss_name = k->xmss_name;
+		k->xmss_name = NULL;
+		free(ret->xmss_filename);
+		ret->xmss_filename = k->xmss_filename;
+		k->xmss_filename = NULL;
+#ifdef DEBUG_PK
+		/* XXX */
+#endif
+		break;
+#endif /* WITH_XMSS */
+	default:
+		sshkey_free(k);
+		return SSH_ERR_INTERNAL_ERROR;
+	}
+	sshkey_free(k);
+
+	/* success */
+	*cpp = cp;
+	return 0;
+}
+
+
+int
+sshkey_to_base64(const struct sshkey *key, char **b64p)
+{
+	int r = SSH_ERR_INTERNAL_ERROR;
+	struct sshbuf *b = NULL;
+	char *uu = NULL;
+
+	if (b64p != NULL)
+		*b64p = NULL;
+	if ((b = sshbuf_new()) == NULL)
+		return SSH_ERR_ALLOC_FAIL;
+	if ((r = sshkey_putb(key, b)) != 0)
+		goto out;
+	if ((uu = sshbuf_dtob64(b)) == NULL) {
+		r = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+	/* Success */
+	if (b64p != NULL) {
+		*b64p = uu;
+		uu = NULL;
+	}
+	r = 0;
+ out:
+	sshbuf_free(b);
+	free(uu);
+	return r;
+}
+
+int
+sshkey_format_text(const struct sshkey *key, struct sshbuf *b)
+{
+	int r = SSH_ERR_INTERNAL_ERROR;
+	char *uu = NULL;
+
+	if ((r = sshkey_to_base64(key, &uu)) != 0)
+		goto out;
+	if ((r = sshbuf_putf(b, "%s %s",
+	    sshkey_ssh_name(key), uu)) != 0)
+		goto out;
+	r = 0;
+ out:
+	free(uu);
+	return r;
+}
+
+int
+sshkey_write(const struct sshkey *key, FILE *f)
+{
+	struct sshbuf *b = NULL;
+	int r = SSH_ERR_INTERNAL_ERROR;
+
+	if ((b = sshbuf_new()) == NULL)
+		return SSH_ERR_ALLOC_FAIL;
+	if ((r = sshkey_format_text(key, b)) != 0)
+		goto out;
+	if (fwrite(sshbuf_ptr(b), sshbuf_len(b), 1, f) != 1) {
+		if (feof(f))
+			errno = EPIPE;
+		r = SSH_ERR_SYSTEM_ERROR;
+		goto out;
+	}
+	/* Success */
+	r = 0;
+ out:
+	sshbuf_free(b);
+	return r;
+}
+
+const char *
+sshkey_cert_type(const struct sshkey *k)
+{
+	switch (k->cert->type) {
+	case SSH2_CERT_TYPE_USER:
+		return "user";
+	case SSH2_CERT_TYPE_HOST:
+		return "host";
+	default:
+		return "unknown";
+	}
+}
+
+#ifdef WITH_OPENSSL
+static int
+rsa_generate_private_key(u_int bits, RSA **rsap)
+{
+	RSA *private = NULL;
+	BIGNUM *f4 = NULL;
+	int ret = SSH_ERR_INTERNAL_ERROR;
+
+	if (rsap == NULL)
+		return SSH_ERR_INVALID_ARGUMENT;
+	if (bits < SSH_RSA_MINIMUM_MODULUS_SIZE ||
+	    bits > SSHBUF_MAX_BIGNUM * 8)
+		return SSH_ERR_KEY_LENGTH;
+	*rsap = NULL;
+	if ((private = RSA_new()) == NULL || (f4 = BN_new()) == NULL) {
+		ret = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+	if (!BN_set_word(f4, RSA_F4) ||
+	    !RSA_generate_key_ex(private, bits, f4, NULL)) {
+		ret = SSH_ERR_LIBCRYPTO_ERROR;
+		goto out;
+	}
+	*rsap = private;
+	private = NULL;
+	ret = 0;
+ out:
+	RSA_free(private);
+	BN_free(f4);
+	return ret;
+}
+
+static int
+dsa_generate_private_key(u_int bits, DSA **dsap)
+{
+	DSA *private;
+	int ret = SSH_ERR_INTERNAL_ERROR;
+
+	if (dsap == NULL)
+		return SSH_ERR_INVALID_ARGUMENT;
+	if (bits != 1024)
+		return SSH_ERR_KEY_LENGTH;
+	if ((private = DSA_new()) == NULL) {
+		ret = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+	*dsap = NULL;
+	if (!DSA_generate_parameters_ex(private, bits, NULL, 0, NULL,
+	    NULL, NULL) || !DSA_generate_key(private)) {
+		ret = SSH_ERR_LIBCRYPTO_ERROR;
+		goto out;
+	}
+	*dsap = private;
+	private = NULL;
+	ret = 0;
+ out:
+	DSA_free(private);
+	return ret;
+}
+
+# ifdef OPENSSL_HAS_ECC
+int
+sshkey_ecdsa_key_to_nid(EC_KEY *k)
+{
+	EC_GROUP *eg;
+	int nids[] = {
+		NID_X9_62_prime256v1,
+		NID_secp384r1,
+#  ifdef OPENSSL_HAS_NISTP521
+		NID_secp521r1,
+#  endif /* OPENSSL_HAS_NISTP521 */
+		-1
+	};
+	int nid;
+	u_int i;
+	BN_CTX *bnctx;
+	const EC_GROUP *g = EC_KEY_get0_group(k);
+
+	/*
+	 * The group may be stored in a ASN.1 encoded private key in one of two
+	 * ways: as a "named group", which is reconstituted by ASN.1 object ID
+	 * or explicit group parameters encoded into the key blob. Only the
+	 * "named group" case sets the group NID for us, but we can figure
+	 * it out for the other case by comparing against all the groups that
+	 * are supported.
+	 */
+	if ((nid = EC_GROUP_get_curve_name(g)) > 0)
+		return nid;
+	if ((bnctx = BN_CTX_new()) == NULL)
+		return -1;
+	for (i = 0; nids[i] != -1; i++) {
+		if ((eg = EC_GROUP_new_by_curve_name(nids[i])) == NULL) {
+			BN_CTX_free(bnctx);
+			return -1;
+		}
+		if (EC_GROUP_cmp(g, eg, bnctx) == 0)
+			break;
+		EC_GROUP_free(eg);
+	}
+	BN_CTX_free(bnctx);
+	if (nids[i] != -1) {
+		/* Use the group with the NID attached */
+		EC_GROUP_set_asn1_flag(eg, OPENSSL_EC_NAMED_CURVE);
+		if (EC_KEY_set_group(k, eg) != 1) {
+			EC_GROUP_free(eg);
+			return -1;
+		}
+	}
+	return nids[i];
+}
+
+static int
+ecdsa_generate_private_key(u_int bits, int *nid, EC_KEY **ecdsap)
+{
+	EC_KEY *private;
+	int ret = SSH_ERR_INTERNAL_ERROR;
+
+	if (nid == NULL || ecdsap == NULL)
+		return SSH_ERR_INVALID_ARGUMENT;
+	if ((*nid = sshkey_ecdsa_bits_to_nid(bits)) == -1)
+		return SSH_ERR_KEY_LENGTH;
+	*ecdsap = NULL;
+	if ((private = EC_KEY_new_by_curve_name(*nid)) == NULL) {
+		ret = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+	if (EC_KEY_generate_key(private) != 1) {
+		ret = SSH_ERR_LIBCRYPTO_ERROR;
+		goto out;
+	}
+	EC_KEY_set_asn1_flag(private, OPENSSL_EC_NAMED_CURVE);
+	*ecdsap = private;
+	private = NULL;
+	ret = 0;
+ out:
+	EC_KEY_free(private);
+	return ret;
+}
+# endif /* OPENSSL_HAS_ECC */
+#endif /* WITH_OPENSSL */
+
+int
+sshkey_generate(int type, u_int bits, struct sshkey **keyp)
+{
+	struct sshkey *k;
+	int ret = SSH_ERR_INTERNAL_ERROR;
+
+	if (keyp == NULL)
+		return SSH_ERR_INVALID_ARGUMENT;
+	*keyp = NULL;
+	if ((k = sshkey_new(KEY_UNSPEC)) == NULL)
+		return SSH_ERR_ALLOC_FAIL;
+	switch (type) {
+	case KEY_ED25519:
+		if ((k->ed25519_pk = malloc(ED25519_PK_SZ)) == NULL ||
+		    (k->ed25519_sk = malloc(ED25519_SK_SZ)) == NULL) {
+			ret = SSH_ERR_ALLOC_FAIL;
+			break;
+		}
+		crypto_sign_ed25519_keypair(k->ed25519_pk, k->ed25519_sk);
+		ret = 0;
+		break;
+#ifdef WITH_XMSS
+	case KEY_XMSS:
+		ret = sshkey_xmss_generate_private_key(k, bits);
+		break;
+#endif /* WITH_XMSS */
+#ifdef WITH_OPENSSL
+	case KEY_DSA:
+		ret = dsa_generate_private_key(bits, &k->dsa);
+		break;
+# ifdef OPENSSL_HAS_ECC
+	case KEY_ECDSA:
+		ret = ecdsa_generate_private_key(bits, &k->ecdsa_nid,
+		    &k->ecdsa);
+		break;
+# endif /* OPENSSL_HAS_ECC */
+	case KEY_RSA:
+		ret = rsa_generate_private_key(bits, &k->rsa);
+		break;
+#endif /* WITH_OPENSSL */
+	default:
+		ret = SSH_ERR_INVALID_ARGUMENT;
+	}
+	if (ret == 0) {
+		k->type = type;
+		*keyp = k;
+	} else
+		sshkey_free(k);
+	return ret;
+}
+
+int
+sshkey_cert_copy(const struct sshkey *from_key, struct sshkey *to_key)
+{
+	u_int i;
+	const struct sshkey_cert *from;
+	struct sshkey_cert *to;
+	int r = SSH_ERR_INTERNAL_ERROR;
+
+	if (to_key == NULL || (from = from_key->cert) == NULL)
+		return SSH_ERR_INVALID_ARGUMENT;
+
+	if ((to = cert_new()) == NULL)
+		return SSH_ERR_ALLOC_FAIL;
+
+	if ((r = sshbuf_putb(to->certblob, from->certblob)) != 0 ||
+	    (r = sshbuf_putb(to->critical, from->critical)) != 0 ||
+	    (r = sshbuf_putb(to->extensions, from->extensions)) != 0)
+		goto out;
+
+	to->serial = from->serial;
+	to->type = from->type;
+	if (from->key_id == NULL)
+		to->key_id = NULL;
+	else if ((to->key_id = strdup(from->key_id)) == NULL) {
+		r = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+	to->valid_after = from->valid_after;
+	to->valid_before = from->valid_before;
+	if (from->signature_key == NULL)
+		to->signature_key = NULL;
+	else if ((r = sshkey_from_private(from->signature_key,
+	    &to->signature_key)) != 0)
+		goto out;
+	if (from->signature_type != NULL &&
+	    (to->signature_type = strdup(from->signature_type)) == NULL) {
+		r = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+	if (from->nprincipals > SSHKEY_CERT_MAX_PRINCIPALS) {
+		r = SSH_ERR_INVALID_ARGUMENT;
+		goto out;
+	}
+	if (from->nprincipals > 0) {
+		if ((to->principals = calloc(from->nprincipals,
+		    sizeof(*to->principals))) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		for (i = 0; i < from->nprincipals; i++) {
+			to->principals[i] = strdup(from->principals[i]);
+			if (to->principals[i] == NULL) {
+				to->nprincipals = i;
+				r = SSH_ERR_ALLOC_FAIL;
+				goto out;
+			}
+		}
+	}
+	to->nprincipals = from->nprincipals;
+
+	/* success */
+	cert_free(to_key->cert);
+	to_key->cert = to;
+	to = NULL;
+	r = 0;
+ out:
+	cert_free(to);
+	return r;
+}
+
+int
+sshkey_from_private(const struct sshkey *k, struct sshkey **pkp)
+{
+	struct sshkey *n = NULL;
+	int r = SSH_ERR_INTERNAL_ERROR;
+#ifdef WITH_OPENSSL
+	const BIGNUM *rsa_n, *rsa_e;
+	BIGNUM *rsa_n_dup = NULL, *rsa_e_dup = NULL;
+	const BIGNUM *dsa_p, *dsa_q, *dsa_g, *dsa_pub_key;
+	BIGNUM *dsa_p_dup = NULL, *dsa_q_dup = NULL, *dsa_g_dup = NULL;
+	BIGNUM *dsa_pub_key_dup = NULL;
+#endif /* WITH_OPENSSL */
+
+	*pkp = NULL;
+	switch (k->type) {
+#ifdef WITH_OPENSSL
+	case KEY_DSA:
+	case KEY_DSA_CERT:
+		if ((n = sshkey_new(k->type)) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+
+		DSA_get0_pqg(k->dsa, &dsa_p, &dsa_q, &dsa_g);
+		DSA_get0_key(k->dsa, &dsa_pub_key, NULL);
+		if ((dsa_p_dup = BN_dup(dsa_p)) == NULL ||
+		    (dsa_q_dup = BN_dup(dsa_q)) == NULL ||
+		    (dsa_g_dup = BN_dup(dsa_g)) == NULL ||
+		    (dsa_pub_key_dup = BN_dup(dsa_pub_key)) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if (!DSA_set0_pqg(n->dsa, dsa_p_dup, dsa_q_dup, dsa_g_dup)) {
+			r = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		dsa_p_dup = dsa_q_dup = dsa_g_dup = NULL; /* transferred */
+		if (!DSA_set0_key(n->dsa, dsa_pub_key_dup, NULL)) {
+			r = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		dsa_pub_key_dup = NULL; /* transferred */
+
+		break;
+# ifdef OPENSSL_HAS_ECC
+	case KEY_ECDSA:
+	case KEY_ECDSA_CERT:
+		if ((n = sshkey_new(k->type)) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		n->ecdsa_nid = k->ecdsa_nid;
+		n->ecdsa = EC_KEY_new_by_curve_name(k->ecdsa_nid);
+		if (n->ecdsa == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if (EC_KEY_set_public_key(n->ecdsa,
+		    EC_KEY_get0_public_key(k->ecdsa)) != 1) {
+			r = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		break;
+# endif /* OPENSSL_HAS_ECC */
+	case KEY_RSA:
+	case KEY_RSA_CERT:
+		if ((n = sshkey_new(k->type)) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		RSA_get0_key(k->rsa, &rsa_n, &rsa_e, NULL);
+		if ((rsa_n_dup = BN_dup(rsa_n)) == NULL ||
+		    (rsa_e_dup = BN_dup(rsa_e)) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if (!RSA_set0_key(n->rsa, rsa_n_dup, rsa_e_dup, NULL)) {
+			r = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		rsa_n_dup = rsa_e_dup = NULL; /* transferred */
+		break;
+#endif /* WITH_OPENSSL */
+	case KEY_ED25519:
+	case KEY_ED25519_CERT:
+		if ((n = sshkey_new(k->type)) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if (k->ed25519_pk != NULL) {
+			if ((n->ed25519_pk = malloc(ED25519_PK_SZ)) == NULL) {
+				r = SSH_ERR_ALLOC_FAIL;
+				goto out;
+			}
+			memcpy(n->ed25519_pk, k->ed25519_pk, ED25519_PK_SZ);
+		}
+		break;
+#ifdef WITH_XMSS
+	case KEY_XMSS:
+	case KEY_XMSS_CERT:
+		if ((n = sshkey_new(k->type)) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if ((r = sshkey_xmss_init(n, k->xmss_name)) != 0)
+			goto out;
+		if (k->xmss_pk != NULL) {
+			size_t pklen = sshkey_xmss_pklen(k);
+			if (pklen == 0 || sshkey_xmss_pklen(n) != pklen) {
+				r = SSH_ERR_INTERNAL_ERROR;
+				goto out;
+			}
+			if ((n->xmss_pk = malloc(pklen)) == NULL) {
+				r = SSH_ERR_ALLOC_FAIL;
+				goto out;
+			}
+			memcpy(n->xmss_pk, k->xmss_pk, pklen);
+		}
+		break;
+#endif /* WITH_XMSS */
+	default:
+		r = SSH_ERR_KEY_TYPE_UNKNOWN;
+		goto out;
+	}
+	if (sshkey_is_cert(k) && (r = sshkey_cert_copy(k, n)) != 0)
+		goto out;
+	/* success */
+	*pkp = n;
+	n = NULL;
+	r = 0;
+ out:
+	sshkey_free(n);
+#ifdef WITH_OPENSSL
+	BN_clear_free(rsa_n_dup);
+	BN_clear_free(rsa_e_dup);
+	BN_clear_free(dsa_p_dup);
+	BN_clear_free(dsa_q_dup);
+	BN_clear_free(dsa_g_dup);
+	BN_clear_free(dsa_pub_key_dup);
+#endif
+
+	return r;
+}
+
+static int
+cert_parse(struct sshbuf *b, struct sshkey *key, struct sshbuf *certbuf)
+{
+	struct sshbuf *principals = NULL, *crit = NULL;
+	struct sshbuf *exts = NULL, *ca = NULL;
+	u_char *sig = NULL;
+	size_t signed_len = 0, slen = 0, kidlen = 0;
+	int ret = SSH_ERR_INTERNAL_ERROR;
+
+	/* Copy the entire key blob for verification and later serialisation */
+	if ((ret = sshbuf_putb(key->cert->certblob, certbuf)) != 0)
+		return ret;
+
+	/* Parse body of certificate up to signature */
+	if ((ret = sshbuf_get_u64(b, &key->cert->serial)) != 0 ||
+	    (ret = sshbuf_get_u32(b, &key->cert->type)) != 0 ||
+	    (ret = sshbuf_get_cstring(b, &key->cert->key_id, &kidlen)) != 0 ||
+	    (ret = sshbuf_froms(b, &principals)) != 0 ||
+	    (ret = sshbuf_get_u64(b, &key->cert->valid_after)) != 0 ||
+	    (ret = sshbuf_get_u64(b, &key->cert->valid_before)) != 0 ||
+	    (ret = sshbuf_froms(b, &crit)) != 0 ||
+	    (ret = sshbuf_froms(b, &exts)) != 0 ||
+	    (ret = sshbuf_get_string_direct(b, NULL, NULL)) != 0 ||
+	    (ret = sshbuf_froms(b, &ca)) != 0) {
+		/* XXX debug print error for ret */
+		ret = SSH_ERR_INVALID_FORMAT;
+		goto out;
+	}
+
+	/* Signature is left in the buffer so we can calculate this length */
+	signed_len = sshbuf_len(key->cert->certblob) - sshbuf_len(b);
+
+	if ((ret = sshbuf_get_string(b, &sig, &slen)) != 0) {
+		ret = SSH_ERR_INVALID_FORMAT;
+		goto out;
+	}
+
+	if (key->cert->type != SSH2_CERT_TYPE_USER &&
+	    key->cert->type != SSH2_CERT_TYPE_HOST) {
+		ret = SSH_ERR_KEY_CERT_UNKNOWN_TYPE;
+		goto out;
+	}
+
+	/* Parse principals section */
+	while (sshbuf_len(principals) > 0) {
+		char *principal = NULL;
+		char **oprincipals = NULL;
+
+		if (key->cert->nprincipals >= SSHKEY_CERT_MAX_PRINCIPALS) {
+			ret = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+		if ((ret = sshbuf_get_cstring(principals, &principal,
+		    NULL)) != 0) {
+			ret = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+		oprincipals = key->cert->principals;
+		key->cert->principals = recallocarray(key->cert->principals,
+		    key->cert->nprincipals, key->cert->nprincipals + 1,
+		    sizeof(*key->cert->principals));
+		if (key->cert->principals == NULL) {
+			free(principal);
+			key->cert->principals = oprincipals;
+			ret = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		key->cert->principals[key->cert->nprincipals++] = principal;
+	}
+
+	/*
+	 * Stash a copies of the critical options and extensions sections
+	 * for later use.
+	 */
+	if ((ret = sshbuf_putb(key->cert->critical, crit)) != 0 ||
+	    (exts != NULL &&
+	    (ret = sshbuf_putb(key->cert->extensions, exts)) != 0))
+		goto out;
+
+	/*
+	 * Validate critical options and extensions sections format.
+	 */
+	while (sshbuf_len(crit) != 0) {
+		if ((ret = sshbuf_get_string_direct(crit, NULL, NULL)) != 0 ||
+		    (ret = sshbuf_get_string_direct(crit, NULL, NULL)) != 0) {
+			sshbuf_reset(key->cert->critical);
+			ret = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+	}
+	while (exts != NULL && sshbuf_len(exts) != 0) {
+		if ((ret = sshbuf_get_string_direct(exts, NULL, NULL)) != 0 ||
+		    (ret = sshbuf_get_string_direct(exts, NULL, NULL)) != 0) {
+			sshbuf_reset(key->cert->extensions);
+			ret = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+	}
+
+	/* Parse CA key and check signature */
+	if (sshkey_from_blob_internal(ca, &key->cert->signature_key, 0) != 0) {
+		ret = SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
+		goto out;
+	}
+	if (!sshkey_type_is_valid_ca(key->cert->signature_key->type)) {
+		ret = SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
+		goto out;
+	}
+	if ((ret = sshkey_verify(key->cert->signature_key, sig, slen,
+	    sshbuf_ptr(key->cert->certblob), signed_len, NULL, 0)) != 0)
+		goto out;
+	if ((ret = get_sigtype(sig, slen, &key->cert->signature_type)) != 0)
+		goto out;
+
+	/* Success */
+	ret = 0;
+ out:
+	sshbuf_free(ca);
+	sshbuf_free(crit);
+	sshbuf_free(exts);
+	sshbuf_free(principals);
+	free(sig);
+	return ret;
+}
+
+#ifdef WITH_OPENSSL
+static int
+check_rsa_length(const RSA *rsa)
+{
+	const BIGNUM *rsa_n;
+
+	RSA_get0_key(rsa, &rsa_n, NULL, NULL);
+	if (BN_num_bits(rsa_n) < SSH_RSA_MINIMUM_MODULUS_SIZE)
+		return SSH_ERR_KEY_LENGTH;
+	return 0;
+}
+#endif
+
+static int
+sshkey_from_blob_internal(struct sshbuf *b, struct sshkey **keyp,
+    int allow_cert)
+{
+	int type, ret = SSH_ERR_INTERNAL_ERROR;
+	char *ktype = NULL, *curve = NULL, *xmss_name = NULL;
+	struct sshkey *key = NULL;
+	size_t len;
+	u_char *pk = NULL;
+	struct sshbuf *copy;
+#if defined(WITH_OPENSSL)
+	BIGNUM *rsa_n = NULL, *rsa_e = NULL;
+	BIGNUM *dsa_p = NULL, *dsa_q = NULL, *dsa_g = NULL, *dsa_pub_key = NULL;
+# if defined(OPENSSL_HAS_ECC)
+	EC_POINT *q = NULL;
+# endif /* OPENSSL_HAS_ECC */
+#endif /* WITH_OPENSSL */
+
+#ifdef DEBUG_PK /* XXX */
+	sshbuf_dump(b, stderr);
+#endif
+	if (keyp != NULL)
+		*keyp = NULL;
+	if ((copy = sshbuf_fromb(b)) == NULL) {
+		ret = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+	if (sshbuf_get_cstring(b, &ktype, NULL) != 0) {
+		ret = SSH_ERR_INVALID_FORMAT;
+		goto out;
+	}
+
+	type = sshkey_type_from_name(ktype);
+	if (!allow_cert && sshkey_type_is_cert(type)) {
+		ret = SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
+		goto out;
+	}
+	switch (type) {
+#ifdef WITH_OPENSSL
+	case KEY_RSA_CERT:
+		/* Skip nonce */
+		if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
+			ret = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+		/* FALLTHROUGH */
+	case KEY_RSA:
+		if ((key = sshkey_new(type)) == NULL) {
+			ret = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if ((rsa_e = BN_new()) == NULL ||
+		    (rsa_n = BN_new()) == NULL) {
+			ret = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if (sshbuf_get_bignum2(b, rsa_e) != 0 ||
+		    sshbuf_get_bignum2(b, rsa_n) != 0) {
+			ret = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+		if (!RSA_set0_key(key->rsa, rsa_n, rsa_e, NULL)) {
+			ret = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		rsa_n = rsa_e = NULL; /* transferred */
+		if ((ret = check_rsa_length(key->rsa)) != 0)
+			goto out;
+#ifdef DEBUG_PK
+		RSA_print_fp(stderr, key->rsa, 8);
+#endif
+		break;
+	case KEY_DSA_CERT:
+		/* Skip nonce */
+		if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
+			ret = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+		/* FALLTHROUGH */
+	case KEY_DSA:
+		if ((key = sshkey_new(type)) == NULL) {
+			ret = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if ((dsa_p = BN_new()) == NULL ||
+		    (dsa_q = BN_new()) == NULL ||
+		    (dsa_g = BN_new()) == NULL ||
+		    (dsa_pub_key = BN_new()) == NULL) {
+			ret = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if (sshbuf_get_bignum2(b, dsa_p) != 0 ||
+		    sshbuf_get_bignum2(b, dsa_q) != 0 ||
+		    sshbuf_get_bignum2(b, dsa_g) != 0 ||
+		    sshbuf_get_bignum2(b, dsa_pub_key) != 0) {
+			ret = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+		if (!DSA_set0_pqg(key->dsa, dsa_p, dsa_q, dsa_g)) {
+			ret = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		dsa_p = dsa_q = dsa_g = NULL; /* transferred */
+		if (!DSA_set0_key(key->dsa, dsa_pub_key, NULL)) {
+			ret = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		dsa_pub_key = NULL; /* transferred */
+#ifdef DEBUG_PK
+		DSA_print_fp(stderr, key->dsa, 8);
+#endif
+		break;
+	case KEY_ECDSA_CERT:
+		/* Skip nonce */
+		if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
+			ret = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+		/* FALLTHROUGH */
+# ifdef OPENSSL_HAS_ECC
+	case KEY_ECDSA:
+		if ((key = sshkey_new(type)) == NULL) {
+			ret = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		key->ecdsa_nid = sshkey_ecdsa_nid_from_name(ktype);
+		if (sshbuf_get_cstring(b, &curve, NULL) != 0) {
+			ret = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+		if (key->ecdsa_nid != sshkey_curve_name_to_nid(curve)) {
+			ret = SSH_ERR_EC_CURVE_MISMATCH;
+			goto out;
+		}
+		EC_KEY_free(key->ecdsa);
+		if ((key->ecdsa = EC_KEY_new_by_curve_name(key->ecdsa_nid))
+		    == NULL) {
+			ret = SSH_ERR_EC_CURVE_INVALID;
+			goto out;
+		}
+		if ((q = EC_POINT_new(EC_KEY_get0_group(key->ecdsa))) == NULL) {
+			ret = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if (sshbuf_get_ec(b, q, EC_KEY_get0_group(key->ecdsa)) != 0) {
+			ret = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+		if (sshkey_ec_validate_public(EC_KEY_get0_group(key->ecdsa),
+		    q) != 0) {
+			ret = SSH_ERR_KEY_INVALID_EC_VALUE;
+			goto out;
+		}
+		if (EC_KEY_set_public_key(key->ecdsa, q) != 1) {
+			/* XXX assume it is a allocation error */
+			ret = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+#ifdef DEBUG_PK
+		sshkey_dump_ec_point(EC_KEY_get0_group(key->ecdsa), q);
+#endif
+		break;
+# endif /* OPENSSL_HAS_ECC */
+#endif /* WITH_OPENSSL */
+	case KEY_ED25519_CERT:
+		/* Skip nonce */
+		if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
+			ret = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+		/* FALLTHROUGH */
+	case KEY_ED25519:
+		if ((ret = sshbuf_get_string(b, &pk, &len)) != 0)
+			goto out;
+		if (len != ED25519_PK_SZ) {
+			ret = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+		if ((key = sshkey_new(type)) == NULL) {
+			ret = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		key->ed25519_pk = pk;
+		pk = NULL;
+		break;
+#ifdef WITH_XMSS
+	case KEY_XMSS_CERT:
+		/* Skip nonce */
+		if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
+			ret = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+		/* FALLTHROUGH */
+	case KEY_XMSS:
+		if ((ret = sshbuf_get_cstring(b, &xmss_name, NULL)) != 0)
+			goto out;
+		if ((key = sshkey_new(type)) == NULL) {
+			ret = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if ((ret = sshkey_xmss_init(key, xmss_name)) != 0)
+			goto out;
+		if ((ret = sshbuf_get_string(b, &pk, &len)) != 0)
+			goto out;
+		if (len == 0 || len != sshkey_xmss_pklen(key)) {
+			ret = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+		key->xmss_pk = pk;
+		pk = NULL;
+		if (type != KEY_XMSS_CERT &&
+		    (ret = sshkey_xmss_deserialize_pk_info(key, b)) != 0)
+			goto out;
+		break;
+#endif /* WITH_XMSS */
+	case KEY_UNSPEC:
+	default:
+		ret = SSH_ERR_KEY_TYPE_UNKNOWN;
+		goto out;
+	}
+
+	/* Parse certificate potion */
+	if (sshkey_is_cert(key) && (ret = cert_parse(b, key, copy)) != 0)
+		goto out;
+
+	if (key != NULL && sshbuf_len(b) != 0) {
+		ret = SSH_ERR_INVALID_FORMAT;
+		goto out;
+	}
+	ret = 0;
+	if (keyp != NULL) {
+		*keyp = key;
+		key = NULL;
+	}
+ out:
+	sshbuf_free(copy);
+	sshkey_free(key);
+	free(xmss_name);
+	free(ktype);
+	free(curve);
+	free(pk);
+#if defined(WITH_OPENSSL)
+	BN_clear_free(rsa_n);
+	BN_clear_free(rsa_e);
+	BN_clear_free(dsa_p);
+	BN_clear_free(dsa_q);
+	BN_clear_free(dsa_g);
+	BN_clear_free(dsa_pub_key);
+# if defined(OPENSSL_HAS_ECC)
+	EC_POINT_free(q);
+# endif /* OPENSSL_HAS_ECC */
+#endif /* WITH_OPENSSL */
+	return ret;
+}
+
+int
+sshkey_from_blob(const u_char *blob, size_t blen, struct sshkey **keyp)
+{
+	struct sshbuf *b;
+	int r;
+
+	if ((b = sshbuf_from(blob, blen)) == NULL)
+		return SSH_ERR_ALLOC_FAIL;
+	r = sshkey_from_blob_internal(b, keyp, 1);
+	sshbuf_free(b);
+	return r;
+}
+
+int
+sshkey_fromb(struct sshbuf *b, struct sshkey **keyp)
+{
+	return sshkey_from_blob_internal(b, keyp, 1);
+}
+
+int
+sshkey_froms(struct sshbuf *buf, struct sshkey **keyp)
+{
+	struct sshbuf *b;
+	int r;
+
+	if ((r = sshbuf_froms(buf, &b)) != 0)
+		return r;
+	r = sshkey_from_blob_internal(b, keyp, 1);
+	sshbuf_free(b);
+	return r;
+}
+
+static int
+get_sigtype(const u_char *sig, size_t siglen, char **sigtypep)
+{
+	int r;
+	struct sshbuf *b = NULL;
+	char *sigtype = NULL;
+
+	if (sigtypep != NULL)
+		*sigtypep = NULL;
+	if ((b = sshbuf_from(sig, siglen)) == NULL)
+		return SSH_ERR_ALLOC_FAIL;
+	if ((r = sshbuf_get_cstring(b, &sigtype, NULL)) != 0)
+		goto out;
+	/* success */
+	if (sigtypep != NULL) {
+		*sigtypep = sigtype;
+		sigtype = NULL;
+	}
+	r = 0;
+ out:
+	free(sigtype);
+	sshbuf_free(b);
+	return r;
+}
+
+/*
+ *
+ * Checks whether a certificate's signature type is allowed.
+ * Returns 0 (success) if the certificate signature type appears in the
+ * "allowed" pattern-list, or the key is not a certificate to begin with.
+ * Otherwise returns a ssherr.h code.
+ */
+int
+sshkey_check_cert_sigtype(const struct sshkey *key, const char *allowed)
+{
+	if (key == NULL || allowed == NULL)
+		return SSH_ERR_INVALID_ARGUMENT;
+	if (!sshkey_type_is_cert(key->type))
+		return 0;
+	if (key->cert == NULL || key->cert->signature_type == NULL)
+		return SSH_ERR_INVALID_ARGUMENT;
+	if (match_pattern_list(key->cert->signature_type, allowed, 0) != 1)
+		return SSH_ERR_SIGN_ALG_UNSUPPORTED;
+	return 0;
+}
+
+/*
+ * Returns the expected signature algorithm for a given public key algorithm.
+ */
+const char *
+sshkey_sigalg_by_name(const char *name)
+{
+	const struct keytype *kt;
+
+	for (kt = keytypes; kt->type != -1; kt++) {
+		if (strcmp(kt->name, name) != 0)
+			continue;
+		if (kt->sigalg != NULL)
+			return kt->sigalg;
+		if (!kt->cert)
+			return kt->name;
+		return sshkey_ssh_name_from_type_nid(
+		    sshkey_type_plain(kt->type), kt->nid);
+	}
+	return NULL;
+}
+
+/*
+ * Verifies that the signature algorithm appearing inside the signature blob
+ * matches that which was requested.
+ */
+int
+sshkey_check_sigtype(const u_char *sig, size_t siglen,
+    const char *requested_alg)
+{
+	const char *expected_alg;
+	char *sigtype = NULL;
+	int r;
+
+	if (requested_alg == NULL)
+		return 0;
+	if ((expected_alg = sshkey_sigalg_by_name(requested_alg)) == NULL)
+		return SSH_ERR_INVALID_ARGUMENT;
+	if ((r = get_sigtype(sig, siglen, &sigtype)) != 0)
+		return r;
+	r = strcmp(expected_alg, sigtype) == 0;
+	free(sigtype);
+	return r ? 0 : SSH_ERR_SIGN_ALG_UNSUPPORTED;
+}
+
+int
+sshkey_sign(const struct sshkey *key,
+    u_char **sigp, size_t *lenp,
+    const u_char *data, size_t datalen, const char *alg, u_int compat)
+{
+	if (sigp != NULL)
+		*sigp = NULL;
+	if (lenp != NULL)
+		*lenp = 0;
+	if (datalen > SSH_KEY_MAX_SIGN_DATA_SIZE)
+		return SSH_ERR_INVALID_ARGUMENT;
+	switch (key->type) {
+#ifdef WITH_OPENSSL
+	case KEY_DSA_CERT:
+	case KEY_DSA:
+		return ssh_dss_sign(key, sigp, lenp, data, datalen, compat);
+# ifdef OPENSSL_HAS_ECC
+	case KEY_ECDSA_CERT:
+	case KEY_ECDSA:
+		return ssh_ecdsa_sign(key, sigp, lenp, data, datalen, compat);
+# endif /* OPENSSL_HAS_ECC */
+	case KEY_RSA_CERT:
+	case KEY_RSA:
+		return ssh_rsa_sign(key, sigp, lenp, data, datalen, alg);
+#endif /* WITH_OPENSSL */
+	case KEY_ED25519:
+	case KEY_ED25519_CERT:
+		return ssh_ed25519_sign(key, sigp, lenp, data, datalen, compat);
+#ifdef WITH_XMSS
+	case KEY_XMSS:
+	case KEY_XMSS_CERT:
+		return ssh_xmss_sign(key, sigp, lenp, data, datalen, compat);
+#endif /* WITH_XMSS */
+	default:
+		return SSH_ERR_KEY_TYPE_UNKNOWN;
+	}
+}
+
+/*
+ * ssh_key_verify returns 0 for a correct signature  and < 0 on error.
+ * If "alg" specified, then the signature must use that algorithm.
+ */
+int
+sshkey_verify(const struct sshkey *key,
+    const u_char *sig, size_t siglen,
+    const u_char *data, size_t dlen, const char *alg, u_int compat)
+{
+	if (siglen == 0 || dlen > SSH_KEY_MAX_SIGN_DATA_SIZE)
+		return SSH_ERR_INVALID_ARGUMENT;
+	switch (key->type) {
+#ifdef WITH_OPENSSL
+	case KEY_DSA_CERT:
+	case KEY_DSA:
+		return ssh_dss_verify(key, sig, siglen, data, dlen, compat);
+# ifdef OPENSSL_HAS_ECC
+	case KEY_ECDSA_CERT:
+	case KEY_ECDSA:
+		return ssh_ecdsa_verify(key, sig, siglen, data, dlen, compat);
+# endif /* OPENSSL_HAS_ECC */
+	case KEY_RSA_CERT:
+	case KEY_RSA:
+		return ssh_rsa_verify(key, sig, siglen, data, dlen, alg);
+#endif /* WITH_OPENSSL */
+	case KEY_ED25519:
+	case KEY_ED25519_CERT:
+		return ssh_ed25519_verify(key, sig, siglen, data, dlen, compat);
+#ifdef WITH_XMSS
+	case KEY_XMSS:
+	case KEY_XMSS_CERT:
+		return ssh_xmss_verify(key, sig, siglen, data, dlen, compat);
+#endif /* WITH_XMSS */
+	default:
+		return SSH_ERR_KEY_TYPE_UNKNOWN;
+	}
+}
+
+/* Convert a plain key to their _CERT equivalent */
+int
+sshkey_to_certified(struct sshkey *k)
+{
+	int newtype;
+
+	switch (k->type) {
+#ifdef WITH_OPENSSL
+	case KEY_RSA:
+		newtype = KEY_RSA_CERT;
+		break;
+	case KEY_DSA:
+		newtype = KEY_DSA_CERT;
+		break;
+	case KEY_ECDSA:
+		newtype = KEY_ECDSA_CERT;
+		break;
+#endif /* WITH_OPENSSL */
+	case KEY_ED25519:
+		newtype = KEY_ED25519_CERT;
+		break;
+#ifdef WITH_XMSS
+	case KEY_XMSS:
+		newtype = KEY_XMSS_CERT;
+		break;
+#endif /* WITH_XMSS */
+	default:
+		return SSH_ERR_INVALID_ARGUMENT;
+	}
+	if ((k->cert = cert_new()) == NULL)
+		return SSH_ERR_ALLOC_FAIL;
+	k->type = newtype;
+	return 0;
+}
+
+/* Convert a certificate to its raw key equivalent */
+int
+sshkey_drop_cert(struct sshkey *k)
+{
+	if (!sshkey_type_is_cert(k->type))
+		return SSH_ERR_KEY_TYPE_UNKNOWN;
+	cert_free(k->cert);
+	k->cert = NULL;
+	k->type = sshkey_type_plain(k->type);
+	return 0;
+}
+
+/* Sign a certified key, (re-)generating the signed certblob. */
+int
+sshkey_certify_custom(struct sshkey *k, struct sshkey *ca, const char *alg,
+    sshkey_certify_signer *signer, void *signer_ctx)
+{
+	struct sshbuf *principals = NULL;
+	u_char *ca_blob = NULL, *sig_blob = NULL, nonce[32];
+	size_t i, ca_len, sig_len;
+	int ret = SSH_ERR_INTERNAL_ERROR;
+	struct sshbuf *cert = NULL;
+	char *sigtype = NULL;
+#ifdef WITH_OPENSSL
+	const BIGNUM *rsa_n, *rsa_e, *dsa_p, *dsa_q, *dsa_g, *dsa_pub_key;
+#endif /* WITH_OPENSSL */
+
+	if (k == NULL || k->cert == NULL ||
+	    k->cert->certblob == NULL || ca == NULL)
+		return SSH_ERR_INVALID_ARGUMENT;
+	if (!sshkey_is_cert(k))
+		return SSH_ERR_KEY_TYPE_UNKNOWN;
+	if (!sshkey_type_is_valid_ca(ca->type))
+		return SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
+
+	/*
+	 * If no alg specified as argument but a signature_type was set,
+	 * then prefer that. If both were specified, then they must match.
+	 */
+	if (alg == NULL)
+		alg = k->cert->signature_type;
+	else if (k->cert->signature_type != NULL &&
+	    strcmp(alg, k->cert->signature_type) != 0)
+		return SSH_ERR_INVALID_ARGUMENT;
+
+	if ((ret = sshkey_to_blob(ca, &ca_blob, &ca_len)) != 0)
+		return SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
+
+	cert = k->cert->certblob; /* for readability */
+	sshbuf_reset(cert);
+	if ((ret = sshbuf_put_cstring(cert, sshkey_ssh_name(k))) != 0)
+		goto out;
+
+	/* -v01 certs put nonce first */
+	arc4random_buf(&nonce, sizeof(nonce));
+	if ((ret = sshbuf_put_string(cert, nonce, sizeof(nonce))) != 0)
+		goto out;
+
+	/* XXX this substantially duplicates to_blob(); refactor */
+	switch (k->type) {
+#ifdef WITH_OPENSSL
+	case KEY_DSA_CERT:
+		DSA_get0_pqg(k->dsa, &dsa_p, &dsa_q, &dsa_g);
+		DSA_get0_key(k->dsa, &dsa_pub_key, NULL);
+		if ((ret = sshbuf_put_bignum2(cert, dsa_p)) != 0 ||
+		    (ret = sshbuf_put_bignum2(cert, dsa_q)) != 0 ||
+		    (ret = sshbuf_put_bignum2(cert, dsa_g)) != 0 ||
+		    (ret = sshbuf_put_bignum2(cert, dsa_pub_key)) != 0)
+			goto out;
+		break;
+# ifdef OPENSSL_HAS_ECC
+	case KEY_ECDSA_CERT:
+		if ((ret = sshbuf_put_cstring(cert,
+		    sshkey_curve_nid_to_name(k->ecdsa_nid))) != 0 ||
+		    (ret = sshbuf_put_ec(cert,
+		    EC_KEY_get0_public_key(k->ecdsa),
+		    EC_KEY_get0_group(k->ecdsa))) != 0)
+			goto out;
+		break;
+# endif /* OPENSSL_HAS_ECC */
+	case KEY_RSA_CERT:
+		RSA_get0_key(k->rsa, &rsa_n, &rsa_e, NULL);
+		if ((ret = sshbuf_put_bignum2(cert, rsa_e)) != 0 ||
+		    (ret = sshbuf_put_bignum2(cert, rsa_n)) != 0)
+			goto out;
+		break;
+#endif /* WITH_OPENSSL */
+	case KEY_ED25519_CERT:
+		if ((ret = sshbuf_put_string(cert,
+		    k->ed25519_pk, ED25519_PK_SZ)) != 0)
+			goto out;
+		break;
+#ifdef WITH_XMSS
+	case KEY_XMSS_CERT:
+		if (k->xmss_name == NULL) {
+			ret = SSH_ERR_INVALID_ARGUMENT;
+			goto out;
+		}
+		if ((ret = sshbuf_put_cstring(cert, k->xmss_name)) ||
+		    (ret = sshbuf_put_string(cert,
+		    k->xmss_pk, sshkey_xmss_pklen(k))) != 0)
+			goto out;
+		break;
+#endif /* WITH_XMSS */
+	default:
+		ret = SSH_ERR_INVALID_ARGUMENT;
+		goto out;
+	}
+
+	if ((ret = sshbuf_put_u64(cert, k->cert->serial)) != 0 ||
+	    (ret = sshbuf_put_u32(cert, k->cert->type)) != 0 ||
+	    (ret = sshbuf_put_cstring(cert, k->cert->key_id)) != 0)
+		goto out;
+
+	if ((principals = sshbuf_new()) == NULL) {
+		ret = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+	for (i = 0; i < k->cert->nprincipals; i++) {
+		if ((ret = sshbuf_put_cstring(principals,
+		    k->cert->principals[i])) != 0)
+			goto out;
+	}
+	if ((ret = sshbuf_put_stringb(cert, principals)) != 0 ||
+	    (ret = sshbuf_put_u64(cert, k->cert->valid_after)) != 0 ||
+	    (ret = sshbuf_put_u64(cert, k->cert->valid_before)) != 0 ||
+	    (ret = sshbuf_put_stringb(cert, k->cert->critical)) != 0 ||
+	    (ret = sshbuf_put_stringb(cert, k->cert->extensions)) != 0 ||
+	    (ret = sshbuf_put_string(cert, NULL, 0)) != 0 || /* Reserved */
+	    (ret = sshbuf_put_string(cert, ca_blob, ca_len)) != 0)
+		goto out;
+
+	/* Sign the whole mess */
+	if ((ret = signer(ca, &sig_blob, &sig_len, sshbuf_ptr(cert),
+	    sshbuf_len(cert), alg, 0, signer_ctx)) != 0)
+		goto out;
+	/* Check and update signature_type against what was actually used */
+	if ((ret = get_sigtype(sig_blob, sig_len, &sigtype)) != 0)
+		goto out;
+	if (alg != NULL && strcmp(alg, sigtype) != 0) {
+		ret = SSH_ERR_SIGN_ALG_UNSUPPORTED;
+		goto out;
+	}
+	if (k->cert->signature_type == NULL) {
+		k->cert->signature_type = sigtype;
+		sigtype = NULL;
+	}
+	/* Append signature and we are done */
+	if ((ret = sshbuf_put_string(cert, sig_blob, sig_len)) != 0)
+		goto out;
+	ret = 0;
+ out:
+	if (ret != 0)
+		sshbuf_reset(cert);
+	free(sig_blob);
+	free(ca_blob);
+	free(sigtype);
+	sshbuf_free(principals);
+	return ret;
+}
+
+static int
+default_key_sign(const struct sshkey *key, u_char **sigp, size_t *lenp,
+    const u_char *data, size_t datalen,
+    const char *alg, u_int compat, void *ctx)
+{
+	if (ctx != NULL)
+		return SSH_ERR_INVALID_ARGUMENT;
+	return sshkey_sign(key, sigp, lenp, data, datalen, alg, compat);
+}
+
+int
+sshkey_certify(struct sshkey *k, struct sshkey *ca, const char *alg)
+{
+	return sshkey_certify_custom(k, ca, alg, default_key_sign, NULL);
+}
+
+int
+sshkey_cert_check_authority(const struct sshkey *k,
+    int want_host, int require_principal,
+    const char *name, const char **reason)
+{
+	u_int i, principal_matches;
+	time_t now = time(NULL);
+
+	if (reason != NULL)
+		*reason = NULL;
+
+	if (want_host) {
+		if (k->cert->type != SSH2_CERT_TYPE_HOST) {
+			*reason = "Certificate invalid: not a host certificate";
+			return SSH_ERR_KEY_CERT_INVALID;
+		}
+	} else {
+		if (k->cert->type != SSH2_CERT_TYPE_USER) {
+			*reason = "Certificate invalid: not a user certificate";
+			return SSH_ERR_KEY_CERT_INVALID;
+		}
+	}
+	if (now < 0) {
+		/* yikes - system clock before epoch! */
+		*reason = "Certificate invalid: not yet valid";
+		return SSH_ERR_KEY_CERT_INVALID;
+	}
+	if ((u_int64_t)now < k->cert->valid_after) {
+		*reason = "Certificate invalid: not yet valid";
+		return SSH_ERR_KEY_CERT_INVALID;
+	}
+	if ((u_int64_t)now >= k->cert->valid_before) {
+		*reason = "Certificate invalid: expired";
+		return SSH_ERR_KEY_CERT_INVALID;
+	}
+	if (k->cert->nprincipals == 0) {
+		if (require_principal) {
+			*reason = "Certificate lacks principal list";
+			return SSH_ERR_KEY_CERT_INVALID;
+		}
+	} else if (name != NULL) {
+		principal_matches = 0;
+		for (i = 0; i < k->cert->nprincipals; i++) {
+			if (strcmp(name, k->cert->principals[i]) == 0) {
+				principal_matches = 1;
+				break;
+			}
+		}
+		if (!principal_matches) {
+			*reason = "Certificate invalid: name is not a listed "
+			    "principal";
+			return SSH_ERR_KEY_CERT_INVALID;
+		}
+	}
+	return 0;
+}
+
+size_t
+sshkey_format_cert_validity(const struct sshkey_cert *cert, char *s, size_t l)
+{
+	char from[32], to[32], ret[64];
+	time_t tt;
+	struct tm *tm;
+
+	*from = *to = '\0';
+	if (cert->valid_after == 0 &&
+	    cert->valid_before == 0xffffffffffffffffULL)
+		return strlcpy(s, "forever", l);
+
+	if (cert->valid_after != 0) {
+		/* XXX revisit INT_MAX in 2038 :) */
+		tt = cert->valid_after > INT_MAX ?
+		    INT_MAX : cert->valid_after;
+		tm = localtime(&tt);
+		strftime(from, sizeof(from), "%Y-%m-%dT%H:%M:%S", tm);
+	}
+	if (cert->valid_before != 0xffffffffffffffffULL) {
+		/* XXX revisit INT_MAX in 2038 :) */
+		tt = cert->valid_before > INT_MAX ?
+		    INT_MAX : cert->valid_before;
+		tm = localtime(&tt);
+		strftime(to, sizeof(to), "%Y-%m-%dT%H:%M:%S", tm);
+	}
+
+	if (cert->valid_after == 0)
+		snprintf(ret, sizeof(ret), "before %s", to);
+	else if (cert->valid_before == 0xffffffffffffffffULL)
+		snprintf(ret, sizeof(ret), "after %s", from);
+	else
+		snprintf(ret, sizeof(ret), "from %s to %s", from, to);
+
+	return strlcpy(s, ret, l);
+}
+
+int
+sshkey_private_serialize_opt(const struct sshkey *key, struct sshbuf *b,
+    enum sshkey_serialize_rep opts)
+{
+	int r = SSH_ERR_INTERNAL_ERROR;
+#ifdef WITH_OPENSSL
+	const BIGNUM *rsa_n, *rsa_e, *rsa_d, *rsa_iqmp, *rsa_p, *rsa_q;
+	const BIGNUM *dsa_p, *dsa_q, *dsa_g, *dsa_pub_key, *dsa_priv_key;
+#endif /* WITH_OPENSSL */
+
+	if ((r = sshbuf_put_cstring(b, sshkey_ssh_name(key))) != 0)
+		goto out;
+	switch (key->type) {
+#ifdef WITH_OPENSSL
+	case KEY_RSA:
+		RSA_get0_key(key->rsa, &rsa_n, &rsa_e, &rsa_d);
+		RSA_get0_factors(key->rsa, &rsa_p, &rsa_q);
+		RSA_get0_crt_params(key->rsa, NULL, NULL, &rsa_iqmp);
+		if ((r = sshbuf_put_bignum2(b, rsa_n)) != 0 ||
+		    (r = sshbuf_put_bignum2(b, rsa_e)) != 0 ||
+		    (r = sshbuf_put_bignum2(b, rsa_d)) != 0 ||
+		    (r = sshbuf_put_bignum2(b, rsa_iqmp)) != 0 ||
+		    (r = sshbuf_put_bignum2(b, rsa_p)) != 0 ||
+		    (r = sshbuf_put_bignum2(b, rsa_q)) != 0)
+			goto out;
+		break;
+	case KEY_RSA_CERT:
+		if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) {
+			r = SSH_ERR_INVALID_ARGUMENT;
+			goto out;
+		}
+		RSA_get0_key(key->rsa, NULL, NULL, &rsa_d);
+		RSA_get0_factors(key->rsa, &rsa_p, &rsa_q);
+		RSA_get0_crt_params(key->rsa, NULL, NULL, &rsa_iqmp);
+		if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 ||
+		    (r = sshbuf_put_bignum2(b, rsa_d)) != 0 ||
+		    (r = sshbuf_put_bignum2(b, rsa_iqmp)) != 0 ||
+		    (r = sshbuf_put_bignum2(b, rsa_p)) != 0 ||
+		    (r = sshbuf_put_bignum2(b, rsa_q)) != 0)
+			goto out;
+		break;
+	case KEY_DSA:
+		DSA_get0_pqg(key->dsa, &dsa_p, &dsa_q, &dsa_g);
+		DSA_get0_key(key->dsa, &dsa_pub_key, &dsa_priv_key);
+		if ((r = sshbuf_put_bignum2(b, dsa_p)) != 0 ||
+		    (r = sshbuf_put_bignum2(b, dsa_q)) != 0 ||
+		    (r = sshbuf_put_bignum2(b, dsa_g)) != 0 ||
+		    (r = sshbuf_put_bignum2(b, dsa_pub_key)) != 0 ||
+		    (r = sshbuf_put_bignum2(b, dsa_priv_key)) != 0)
+			goto out;
+		break;
+	case KEY_DSA_CERT:
+		if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) {
+			r = SSH_ERR_INVALID_ARGUMENT;
+			goto out;
+		}
+		DSA_get0_key(key->dsa, NULL, &dsa_priv_key);
+		if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 ||
+		    (r = sshbuf_put_bignum2(b, dsa_priv_key)) != 0)
+			goto out;
+		break;
+# ifdef OPENSSL_HAS_ECC
+	case KEY_ECDSA:
+		if ((r = sshbuf_put_cstring(b,
+		    sshkey_curve_nid_to_name(key->ecdsa_nid))) != 0 ||
+		    (r = sshbuf_put_eckey(b, key->ecdsa)) != 0 ||
+		    (r = sshbuf_put_bignum2(b,
+		    EC_KEY_get0_private_key(key->ecdsa))) != 0)
+			goto out;
+		break;
+	case KEY_ECDSA_CERT:
+		if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) {
+			r = SSH_ERR_INVALID_ARGUMENT;
+			goto out;
+		}
+		if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 ||
+		    (r = sshbuf_put_bignum2(b,
+		    EC_KEY_get0_private_key(key->ecdsa))) != 0)
+			goto out;
+		break;
+# endif /* OPENSSL_HAS_ECC */
+#endif /* WITH_OPENSSL */
+	case KEY_ED25519:
+		if ((r = sshbuf_put_string(b, key->ed25519_pk,
+		    ED25519_PK_SZ)) != 0 ||
+		    (r = sshbuf_put_string(b, key->ed25519_sk,
+		    ED25519_SK_SZ)) != 0)
+			goto out;
+		break;
+	case KEY_ED25519_CERT:
+		if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) {
+			r = SSH_ERR_INVALID_ARGUMENT;
+			goto out;
+		}
+		if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 ||
+		    (r = sshbuf_put_string(b, key->ed25519_pk,
+		    ED25519_PK_SZ)) != 0 ||
+		    (r = sshbuf_put_string(b, key->ed25519_sk,
+		    ED25519_SK_SZ)) != 0)
+			goto out;
+		break;
+#ifdef WITH_XMSS
+	case KEY_XMSS:
+		if (key->xmss_name == NULL) {
+			r = SSH_ERR_INVALID_ARGUMENT;
+			goto out;
+		}
+		if ((r = sshbuf_put_cstring(b, key->xmss_name)) != 0 ||
+		    (r = sshbuf_put_string(b, key->xmss_pk,
+		    sshkey_xmss_pklen(key))) != 0 ||
+		    (r = sshbuf_put_string(b, key->xmss_sk,
+		    sshkey_xmss_sklen(key))) != 0 ||
+		    (r = sshkey_xmss_serialize_state_opt(key, b, opts)) != 0)
+			goto out;
+		break;
+	case KEY_XMSS_CERT:
+		if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0 ||
+		    key->xmss_name == NULL) {
+			r = SSH_ERR_INVALID_ARGUMENT;
+			goto out;
+		}
+		if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 ||
+		    (r = sshbuf_put_cstring(b, key->xmss_name)) != 0 ||
+		    (r = sshbuf_put_string(b, key->xmss_pk,
+		    sshkey_xmss_pklen(key))) != 0 ||
+		    (r = sshbuf_put_string(b, key->xmss_sk,
+		    sshkey_xmss_sklen(key))) != 0 ||
+		    (r = sshkey_xmss_serialize_state_opt(key, b, opts)) != 0)
+			goto out;
+		break;
+#endif /* WITH_XMSS */
+	default:
+		r = SSH_ERR_INVALID_ARGUMENT;
+		goto out;
+	}
+	/* success */
+	r = 0;
+ out:
+	return r;
+}
+
+int
+sshkey_private_serialize(const struct sshkey *key, struct sshbuf *b)
+{
+	return sshkey_private_serialize_opt(key, b,
+	    SSHKEY_SERIALIZE_DEFAULT);
+}
+
+int
+sshkey_private_deserialize(struct sshbuf *buf, struct sshkey **kp)
+{
+	char *tname = NULL, *curve = NULL, *xmss_name = NULL;
+	struct sshkey *k = NULL;
+	size_t pklen = 0, sklen = 0;
+	int type, r = SSH_ERR_INTERNAL_ERROR;
+	u_char *ed25519_pk = NULL, *ed25519_sk = NULL;
+	u_char *xmss_pk = NULL, *xmss_sk = NULL;
+#ifdef WITH_OPENSSL
+	BIGNUM *exponent = NULL;
+	BIGNUM *rsa_n = NULL, *rsa_e = NULL, *rsa_d = NULL;
+	BIGNUM *rsa_iqmp = NULL, *rsa_p = NULL, *rsa_q = NULL;
+	BIGNUM *dsa_p = NULL, *dsa_q = NULL, *dsa_g = NULL;
+	BIGNUM *dsa_pub_key = NULL, *dsa_priv_key = NULL;
+#endif /* WITH_OPENSSL */
+
+	if (kp != NULL)
+		*kp = NULL;
+	if ((r = sshbuf_get_cstring(buf, &tname, NULL)) != 0)
+		goto out;
+	type = sshkey_type_from_name(tname);
+	switch (type) {
+#ifdef WITH_OPENSSL
+	case KEY_DSA:
+		if ((k = sshkey_new(type)) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if ((dsa_p = BN_new()) == NULL ||
+		    (dsa_q = BN_new()) == NULL ||
+		    (dsa_g = BN_new()) == NULL ||
+		    (dsa_pub_key = BN_new()) == NULL ||
+		    (dsa_priv_key = BN_new()) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if ((r = sshbuf_get_bignum2(buf, dsa_p)) != 0 ||
+		    (r = sshbuf_get_bignum2(buf, dsa_q)) != 0 ||
+		    (r = sshbuf_get_bignum2(buf, dsa_g)) != 0 ||
+		    (r = sshbuf_get_bignum2(buf, dsa_pub_key)) != 0 ||
+		    (r = sshbuf_get_bignum2(buf, dsa_priv_key)) != 0)
+			goto out;
+		if (!DSA_set0_pqg(k->dsa, dsa_p, dsa_q, dsa_g)) {
+			r = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		dsa_p = dsa_q = dsa_g = NULL; /* transferred */
+		if (!DSA_set0_key(k->dsa, dsa_pub_key, dsa_priv_key)) {
+			r = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		dsa_pub_key = dsa_priv_key = NULL; /* transferred */
+		break;
+	case KEY_DSA_CERT:
+		if ((dsa_priv_key = BN_new()) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if ((r = sshkey_froms(buf, &k)) != 0 ||
+		    (r = sshbuf_get_bignum2(buf, dsa_priv_key)) != 0)
+			goto out;
+		if (!DSA_set0_key(k->dsa, NULL, dsa_priv_key)) {
+			r = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		dsa_priv_key = NULL; /* transferred */
+		break;
+# ifdef OPENSSL_HAS_ECC
+	case KEY_ECDSA:
+		if ((k = sshkey_new(type)) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if ((k->ecdsa_nid = sshkey_ecdsa_nid_from_name(tname)) == -1) {
+			r = SSH_ERR_INVALID_ARGUMENT;
+			goto out;
+		}
+		if ((r = sshbuf_get_cstring(buf, &curve, NULL)) != 0)
+			goto out;
+		if (k->ecdsa_nid != sshkey_curve_name_to_nid(curve)) {
+			r = SSH_ERR_EC_CURVE_MISMATCH;
+			goto out;
+		}
+		k->ecdsa = EC_KEY_new_by_curve_name(k->ecdsa_nid);
+		if (k->ecdsa  == NULL || (exponent = BN_new()) == NULL) {
+			r = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		if ((r = sshbuf_get_eckey(buf, k->ecdsa)) != 0 ||
+		    (r = sshbuf_get_bignum2(buf, exponent)))
+			goto out;
+		if (EC_KEY_set_private_key(k->ecdsa, exponent) != 1) {
+			r = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		if ((r = sshkey_ec_validate_public(EC_KEY_get0_group(k->ecdsa),
+		    EC_KEY_get0_public_key(k->ecdsa))) != 0 ||
+		    (r = sshkey_ec_validate_private(k->ecdsa)) != 0)
+			goto out;
+		break;
+	case KEY_ECDSA_CERT:
+		if ((exponent = BN_new()) == NULL) {
+			r = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		if ((r = sshkey_froms(buf, &k)) != 0 ||
+		    (r = sshbuf_get_bignum2(buf, exponent)) != 0)
+			goto out;
+		if (EC_KEY_set_private_key(k->ecdsa, exponent) != 1) {
+			r = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		if ((r = sshkey_ec_validate_public(EC_KEY_get0_group(k->ecdsa),
+		    EC_KEY_get0_public_key(k->ecdsa))) != 0 ||
+		    (r = sshkey_ec_validate_private(k->ecdsa)) != 0)
+			goto out;
+		break;
+# endif /* OPENSSL_HAS_ECC */
+	case KEY_RSA:
+		if ((k = sshkey_new(type)) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if ((rsa_n = BN_new()) == NULL ||
+		    (rsa_e = BN_new()) == NULL ||
+		    (rsa_d = BN_new()) == NULL ||
+		    (rsa_iqmp = BN_new()) == NULL ||
+		    (rsa_p = BN_new()) == NULL ||
+		    (rsa_q = BN_new()) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if ((r = sshbuf_get_bignum2(buf, rsa_n)) != 0 ||
+		    (r = sshbuf_get_bignum2(buf, rsa_e)) != 0 ||
+		    (r = sshbuf_get_bignum2(buf, rsa_d)) != 0 ||
+		    (r = sshbuf_get_bignum2(buf, rsa_iqmp)) != 0 ||
+		    (r = sshbuf_get_bignum2(buf, rsa_p)) != 0 ||
+		    (r = sshbuf_get_bignum2(buf, rsa_q)) != 0)
+			goto out;
+		if (!RSA_set0_key(k->rsa, rsa_n, rsa_e, rsa_d)) {
+			r = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		rsa_n = rsa_e = rsa_d = NULL; /* transferred */
+		if (!RSA_set0_factors(k->rsa, rsa_p, rsa_q)) {
+			r = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		rsa_p = rsa_q = NULL; /* transferred */
+		if ((r = check_rsa_length(k->rsa)) != 0)
+			goto out;
+		if ((r = ssh_rsa_complete_crt_parameters(k, rsa_iqmp)) != 0)
+			goto out;
+		break;
+	case KEY_RSA_CERT:
+		if ((rsa_d = BN_new()) == NULL ||
+		    (rsa_iqmp = BN_new()) == NULL ||
+		    (rsa_p = BN_new()) == NULL ||
+		    (rsa_q = BN_new()) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if ((r = sshkey_froms(buf, &k)) != 0 ||
+		    (r = sshbuf_get_bignum2(buf, rsa_d)) != 0 ||
+		    (r = sshbuf_get_bignum2(buf, rsa_iqmp)) != 0 ||
+		    (r = sshbuf_get_bignum2(buf, rsa_p)) != 0 ||
+		    (r = sshbuf_get_bignum2(buf, rsa_q)) != 0)
+			goto out;
+		if (!RSA_set0_key(k->rsa, NULL, NULL, rsa_d)) {
+			r = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		rsa_d = NULL; /* transferred */
+		if (!RSA_set0_factors(k->rsa, rsa_p, rsa_q)) {
+			r = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		rsa_p = rsa_q = NULL; /* transferred */
+		if ((r = check_rsa_length(k->rsa)) != 0)
+			goto out;
+		if ((r = ssh_rsa_complete_crt_parameters(k, rsa_iqmp)) != 0)
+			goto out;
+		break;
+#endif /* WITH_OPENSSL */
+	case KEY_ED25519:
+		if ((k = sshkey_new(type)) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if ((r = sshbuf_get_string(buf, &ed25519_pk, &pklen)) != 0 ||
+		    (r = sshbuf_get_string(buf, &ed25519_sk, &sklen)) != 0)
+			goto out;
+		if (pklen != ED25519_PK_SZ || sklen != ED25519_SK_SZ) {
+			r = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+		k->ed25519_pk = ed25519_pk;
+		k->ed25519_sk = ed25519_sk;
+		ed25519_pk = ed25519_sk = NULL;
+		break;
+	case KEY_ED25519_CERT:
+		if ((r = sshkey_froms(buf, &k)) != 0 ||
+		    (r = sshbuf_get_string(buf, &ed25519_pk, &pklen)) != 0 ||
+		    (r = sshbuf_get_string(buf, &ed25519_sk, &sklen)) != 0)
+			goto out;
+		if (pklen != ED25519_PK_SZ || sklen != ED25519_SK_SZ) {
+			r = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+		k->ed25519_pk = ed25519_pk;
+		k->ed25519_sk = ed25519_sk;
+		ed25519_pk = ed25519_sk = NULL;
+		break;
+#ifdef WITH_XMSS
+	case KEY_XMSS:
+		if ((k = sshkey_new(type)) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		if ((r = sshbuf_get_cstring(buf, &xmss_name, NULL)) != 0 ||
+		    (r = sshkey_xmss_init(k, xmss_name)) != 0 ||
+		    (r = sshbuf_get_string(buf, &xmss_pk, &pklen)) != 0 ||
+		    (r = sshbuf_get_string(buf, &xmss_sk, &sklen)) != 0)
+			goto out;
+		if (pklen != sshkey_xmss_pklen(k) ||
+		    sklen != sshkey_xmss_sklen(k)) {
+			r = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+		k->xmss_pk = xmss_pk;
+		k->xmss_sk = xmss_sk;
+		xmss_pk = xmss_sk = NULL;
+		/* optional internal state */
+		if ((r = sshkey_xmss_deserialize_state_opt(k, buf)) != 0)
+			goto out;
+		break;
+	case KEY_XMSS_CERT:
+		if ((r = sshkey_froms(buf, &k)) != 0 ||
+		    (r = sshbuf_get_cstring(buf, &xmss_name, NULL)) != 0 ||
+		    (r = sshbuf_get_string(buf, &xmss_pk, &pklen)) != 0 ||
+		    (r = sshbuf_get_string(buf, &xmss_sk, &sklen)) != 0)
+			goto out;
+		if (strcmp(xmss_name, k->xmss_name)) {
+			r = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+		if (pklen != sshkey_xmss_pklen(k) ||
+		    sklen != sshkey_xmss_sklen(k)) {
+			r = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+		k->xmss_pk = xmss_pk;
+		k->xmss_sk = xmss_sk;
+		xmss_pk = xmss_sk = NULL;
+		/* optional internal state */
+		if ((r = sshkey_xmss_deserialize_state_opt(k, buf)) != 0)
+			goto out;
+		break;
+#endif /* WITH_XMSS */
+	default:
+		r = SSH_ERR_KEY_TYPE_UNKNOWN;
+		goto out;
+	}
+#ifdef WITH_OPENSSL
+	/* enable blinding */
+	switch (k->type) {
+	case KEY_RSA:
+	case KEY_RSA_CERT:
+		if (RSA_blinding_on(k->rsa, NULL) != 1) {
+			r = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		break;
+	}
+#endif /* WITH_OPENSSL */
+	/* success */
+	r = 0;
+	if (kp != NULL) {
+		*kp = k;
+		k = NULL;
+	}
+ out:
+	free(tname);
+	free(curve);
+#ifdef WITH_OPENSSL
+	BN_clear_free(exponent);
+	BN_clear_free(dsa_p);
+	BN_clear_free(dsa_q);
+	BN_clear_free(dsa_g);
+	BN_clear_free(dsa_pub_key);
+	BN_clear_free(dsa_priv_key);
+	BN_clear_free(rsa_n);
+	BN_clear_free(rsa_e);
+	BN_clear_free(rsa_d);
+	BN_clear_free(rsa_p);
+	BN_clear_free(rsa_q);
+	BN_clear_free(rsa_iqmp);
+#endif /* WITH_OPENSSL */
+	sshkey_free(k);
+	freezero(ed25519_pk, pklen);
+	freezero(ed25519_sk, sklen);
+	free(xmss_name);
+	freezero(xmss_pk, pklen);
+	freezero(xmss_sk, sklen);
+	return r;
+}
+
+#if defined(WITH_OPENSSL) && defined(OPENSSL_HAS_ECC)
+int
+sshkey_ec_validate_public(const EC_GROUP *group, const EC_POINT *public)
+{
+	BN_CTX *bnctx;
+	EC_POINT *nq = NULL;
+	BIGNUM *order, *x, *y, *tmp;
+	int ret = SSH_ERR_KEY_INVALID_EC_VALUE;
+
+	/*
+	 * NB. This assumes OpenSSL has already verified that the public
+	 * point lies on the curve. This is done by EC_POINT_oct2point()
+	 * implicitly calling EC_POINT_is_on_curve(). If this code is ever
+	 * reachable with public points not unmarshalled using
+	 * EC_POINT_oct2point then the caller will need to explicitly check.
+	 */
+
+	if ((bnctx = BN_CTX_new()) == NULL)
+		return SSH_ERR_ALLOC_FAIL;
+	BN_CTX_start(bnctx);
+
+	/*
+	 * We shouldn't ever hit this case because bignum_get_ecpoint()
+	 * refuses to load GF2m points.
+	 */
+	if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) !=
+	    NID_X9_62_prime_field)
+		goto out;
+
+	/* Q != infinity */
+	if (EC_POINT_is_at_infinity(group, public))
+		goto out;
+
+	if ((x = BN_CTX_get(bnctx)) == NULL ||
+	    (y = BN_CTX_get(bnctx)) == NULL ||
+	    (order = BN_CTX_get(bnctx)) == NULL ||
+	    (tmp = BN_CTX_get(bnctx)) == NULL) {
+		ret = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+
+	/* log2(x) > log2(order)/2, log2(y) > log2(order)/2 */
+	if (EC_GROUP_get_order(group, order, bnctx) != 1 ||
+	    EC_POINT_get_affine_coordinates_GFp(group, public,
+	    x, y, bnctx) != 1) {
+		ret = SSH_ERR_LIBCRYPTO_ERROR;
+		goto out;
+	}
+	if (BN_num_bits(x) <= BN_num_bits(order) / 2 ||
+	    BN_num_bits(y) <= BN_num_bits(order) / 2)
+		goto out;
+
+	/* nQ == infinity (n == order of subgroup) */
+	if ((nq = EC_POINT_new(group)) == NULL) {
+		ret = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+	if (EC_POINT_mul(group, nq, NULL, public, order, bnctx) != 1) {
+		ret = SSH_ERR_LIBCRYPTO_ERROR;
+		goto out;
+	}
+	if (EC_POINT_is_at_infinity(group, nq) != 1)
+		goto out;
+
+	/* x < order - 1, y < order - 1 */
+	if (!BN_sub(tmp, order, BN_value_one())) {
+		ret = SSH_ERR_LIBCRYPTO_ERROR;
+		goto out;
+	}
+	if (BN_cmp(x, tmp) >= 0 || BN_cmp(y, tmp) >= 0)
+		goto out;
+	ret = 0;
+ out:
+	BN_CTX_free(bnctx);
+	EC_POINT_free(nq);
+	return ret;
+}
+
+int
+sshkey_ec_validate_private(const EC_KEY *key)
+{
+	BN_CTX *bnctx;
+	BIGNUM *order, *tmp;
+	int ret = SSH_ERR_KEY_INVALID_EC_VALUE;
+
+	if ((bnctx = BN_CTX_new()) == NULL)
+		return SSH_ERR_ALLOC_FAIL;
+	BN_CTX_start(bnctx);
+
+	if ((order = BN_CTX_get(bnctx)) == NULL ||
+	    (tmp = BN_CTX_get(bnctx)) == NULL) {
+		ret = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+
+	/* log2(private) > log2(order)/2 */
+	if (EC_GROUP_get_order(EC_KEY_get0_group(key), order, bnctx) != 1) {
+		ret = SSH_ERR_LIBCRYPTO_ERROR;
+		goto out;
+	}
+	if (BN_num_bits(EC_KEY_get0_private_key(key)) <=
+	    BN_num_bits(order) / 2)
+		goto out;
+
+	/* private < order - 1 */
+	if (!BN_sub(tmp, order, BN_value_one())) {
+		ret = SSH_ERR_LIBCRYPTO_ERROR;
+		goto out;
+	}
+	if (BN_cmp(EC_KEY_get0_private_key(key), tmp) >= 0)
+		goto out;
+	ret = 0;
+ out:
+	BN_CTX_free(bnctx);
+	return ret;
+}
+
+void
+sshkey_dump_ec_point(const EC_GROUP *group, const EC_POINT *point)
+{
+	BIGNUM *x, *y;
+	BN_CTX *bnctx;
+
+	if (point == NULL) {
+		fputs("point=(NULL)\n", stderr);
+		return;
+	}
+	if ((bnctx = BN_CTX_new()) == NULL) {
+		fprintf(stderr, "%s: BN_CTX_new failed\n", __func__);
+		return;
+	}
+	BN_CTX_start(bnctx);
+	if ((x = BN_CTX_get(bnctx)) == NULL ||
+	    (y = BN_CTX_get(bnctx)) == NULL) {
+		fprintf(stderr, "%s: BN_CTX_get failed\n", __func__);
+		return;
+	}
+	if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) !=
+	    NID_X9_62_prime_field) {
+		fprintf(stderr, "%s: group is not a prime field\n", __func__);
+		return;
+	}
+	if (EC_POINT_get_affine_coordinates_GFp(group, point, x, y,
+	    bnctx) != 1) {
+		fprintf(stderr, "%s: EC_POINT_get_affine_coordinates_GFp\n",
+		    __func__);
+		return;
+	}
+	fputs("x=", stderr);
+	BN_print_fp(stderr, x);
+	fputs("\ny=", stderr);
+	BN_print_fp(stderr, y);
+	fputs("\n", stderr);
+	BN_CTX_free(bnctx);
+}
+
+void
+sshkey_dump_ec_key(const EC_KEY *key)
+{
+	const BIGNUM *exponent;
+
+	sshkey_dump_ec_point(EC_KEY_get0_group(key),
+	    EC_KEY_get0_public_key(key));
+	fputs("exponent=", stderr);
+	if ((exponent = EC_KEY_get0_private_key(key)) == NULL)
+		fputs("(NULL)", stderr);
+	else
+		BN_print_fp(stderr, EC_KEY_get0_private_key(key));
+	fputs("\n", stderr);
+}
+#endif /* WITH_OPENSSL && OPENSSL_HAS_ECC */
+
+static int
+sshkey_private_to_blob2(const struct sshkey *prv, struct sshbuf *blob,
+    const char *passphrase, const char *comment, const char *ciphername,
+    int rounds)
+{
+	u_char *cp, *key = NULL, *pubkeyblob = NULL;
+	u_char salt[SALT_LEN];
+	char *b64 = NULL;
+	size_t i, pubkeylen, keylen, ivlen, blocksize, authlen;
+	u_int check;
+	int r = SSH_ERR_INTERNAL_ERROR;
+	struct sshcipher_ctx *ciphercontext = NULL;
+	const struct sshcipher *cipher;
+	const char *kdfname = KDFNAME;
+	struct sshbuf *encoded = NULL, *encrypted = NULL, *kdf = NULL;
+
+	if (rounds <= 0)
+		rounds = DEFAULT_ROUNDS;
+	if (passphrase == NULL || !strlen(passphrase)) {
+		ciphername = "none";
+		kdfname = "none";
+	} else if (ciphername == NULL)
+		ciphername = DEFAULT_CIPHERNAME;
+	if ((cipher = cipher_by_name(ciphername)) == NULL) {
+		r = SSH_ERR_INVALID_ARGUMENT;
+		goto out;
+	}
+
+	if ((kdf = sshbuf_new()) == NULL ||
+	    (encoded = sshbuf_new()) == NULL ||
+	    (encrypted = sshbuf_new()) == NULL) {
+		r = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+	blocksize = cipher_blocksize(cipher);
+	keylen = cipher_keylen(cipher);
+	ivlen = cipher_ivlen(cipher);
+	authlen = cipher_authlen(cipher);
+	if ((key = calloc(1, keylen + ivlen)) == NULL) {
+		r = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+	if (strcmp(kdfname, "bcrypt") == 0) {
+		arc4random_buf(salt, SALT_LEN);
+		if (bcrypt_pbkdf(passphrase, strlen(passphrase),
+		    salt, SALT_LEN, key, keylen + ivlen, rounds) < 0) {
+			r = SSH_ERR_INVALID_ARGUMENT;
+			goto out;
+		}
+		if ((r = sshbuf_put_string(kdf, salt, SALT_LEN)) != 0 ||
+		    (r = sshbuf_put_u32(kdf, rounds)) != 0)
+			goto out;
+	} else if (strcmp(kdfname, "none") != 0) {
+		/* Unsupported KDF type */
+		r = SSH_ERR_KEY_UNKNOWN_CIPHER;
+		goto out;
+	}
+	if ((r = cipher_init(&ciphercontext, cipher, key, keylen,
+	    key + keylen, ivlen, 1)) != 0)
+		goto out;
+
+	if ((r = sshbuf_put(encoded, AUTH_MAGIC, sizeof(AUTH_MAGIC))) != 0 ||
+	    (r = sshbuf_put_cstring(encoded, ciphername)) != 0 ||
+	    (r = sshbuf_put_cstring(encoded, kdfname)) != 0 ||
+	    (r = sshbuf_put_stringb(encoded, kdf)) != 0 ||
+	    (r = sshbuf_put_u32(encoded, 1)) != 0 ||	/* number of keys */
+	    (r = sshkey_to_blob(prv, &pubkeyblob, &pubkeylen)) != 0 ||
+	    (r = sshbuf_put_string(encoded, pubkeyblob, pubkeylen)) != 0)
+		goto out;
+
+	/* set up the buffer that will be encrypted */
+
+	/* Random check bytes */
+	check = arc4random();
+	if ((r = sshbuf_put_u32(encrypted, check)) != 0 ||
+	    (r = sshbuf_put_u32(encrypted, check)) != 0)
+		goto out;
+
+	/* append private key and comment*/
+	if ((r = sshkey_private_serialize_opt(prv, encrypted,
+	     SSHKEY_SERIALIZE_FULL)) != 0 ||
+	    (r = sshbuf_put_cstring(encrypted, comment)) != 0)
+		goto out;
+
+	/* padding */
+	i = 0;
+	while (sshbuf_len(encrypted) % blocksize) {
+		if ((r = sshbuf_put_u8(encrypted, ++i & 0xff)) != 0)
+			goto out;
+	}
+
+	/* length in destination buffer */
+	if ((r = sshbuf_put_u32(encoded, sshbuf_len(encrypted))) != 0)
+		goto out;
+
+	/* encrypt */
+	if ((r = sshbuf_reserve(encoded,
+	    sshbuf_len(encrypted) + authlen, &cp)) != 0)
+		goto out;
+	if ((r = cipher_crypt(ciphercontext, 0, cp,
+	    sshbuf_ptr(encrypted), sshbuf_len(encrypted), 0, authlen)) != 0)
+		goto out;
+
+	/* uuencode */
+	if ((b64 = sshbuf_dtob64(encoded)) == NULL) {
+		r = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+
+	sshbuf_reset(blob);
+	if ((r = sshbuf_put(blob, MARK_BEGIN, MARK_BEGIN_LEN)) != 0)
+		goto out;
+	for (i = 0; i < strlen(b64); i++) {
+		if ((r = sshbuf_put_u8(blob, b64[i])) != 0)
+			goto out;
+		/* insert line breaks */
+		if (i % 70 == 69 && (r = sshbuf_put_u8(blob, '\n')) != 0)
+			goto out;
+	}
+	if (i % 70 != 69 && (r = sshbuf_put_u8(blob, '\n')) != 0)
+		goto out;
+	if ((r = sshbuf_put(blob, MARK_END, MARK_END_LEN)) != 0)
+		goto out;
+
+	/* success */
+	r = 0;
+
+ out:
+	sshbuf_free(kdf);
+	sshbuf_free(encoded);
+	sshbuf_free(encrypted);
+	cipher_free(ciphercontext);
+	explicit_bzero(salt, sizeof(salt));
+	if (key != NULL) {
+		explicit_bzero(key, keylen + ivlen);
+		free(key);
+	}
+	if (pubkeyblob != NULL) {
+		explicit_bzero(pubkeyblob, pubkeylen);
+		free(pubkeyblob);
+	}
+	if (b64 != NULL) {
+		explicit_bzero(b64, strlen(b64));
+		free(b64);
+	}
+	return r;
+}
+
+static int
+sshkey_parse_private2(struct sshbuf *blob, int type, const char *passphrase,
+    struct sshkey **keyp, char **commentp)
+{
+	char *comment = NULL, *ciphername = NULL, *kdfname = NULL;
+	const struct sshcipher *cipher = NULL;
+	const u_char *cp;
+	int r = SSH_ERR_INTERNAL_ERROR;
+	size_t encoded_len;
+	size_t i, keylen = 0, ivlen = 0, authlen = 0, slen = 0;
+	struct sshbuf *encoded = NULL, *decoded = NULL;
+	struct sshbuf *kdf = NULL, *decrypted = NULL;
+	struct sshcipher_ctx *ciphercontext = NULL;
+	struct sshkey *k = NULL;
+	u_char *key = NULL, *salt = NULL, *dp, pad, last;
+	u_int blocksize, rounds, nkeys, encrypted_len, check1, check2;
+
+	if (keyp != NULL)
+		*keyp = NULL;
+	if (commentp != NULL)
+		*commentp = NULL;
+
+	if ((encoded = sshbuf_new()) == NULL ||
+	    (decoded = sshbuf_new()) == NULL ||
+	    (decrypted = sshbuf_new()) == NULL) {
+		r = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+
+	/* check preamble */
+	cp = sshbuf_ptr(blob);
+	encoded_len = sshbuf_len(blob);
+	if (encoded_len < (MARK_BEGIN_LEN + MARK_END_LEN) ||
+	    memcmp(cp, MARK_BEGIN, MARK_BEGIN_LEN) != 0) {
+		r = SSH_ERR_INVALID_FORMAT;
+		goto out;
+	}
+	cp += MARK_BEGIN_LEN;
+	encoded_len -= MARK_BEGIN_LEN;
+
+	/* Look for end marker, removing whitespace as we go */
+	while (encoded_len > 0) {
+		if (*cp != '\n' && *cp != '\r') {
+			if ((r = sshbuf_put_u8(encoded, *cp)) != 0)
+				goto out;
+		}
+		last = *cp;
+		encoded_len--;
+		cp++;
+		if (last == '\n') {
+			if (encoded_len >= MARK_END_LEN &&
+			    memcmp(cp, MARK_END, MARK_END_LEN) == 0) {
+				/* \0 terminate */
+				if ((r = sshbuf_put_u8(encoded, 0)) != 0)
+					goto out;
+				break;
+			}
+		}
+	}
+	if (encoded_len == 0) {
+		r = SSH_ERR_INVALID_FORMAT;
+		goto out;
+	}
+
+	/* decode base64 */
+	if ((r = sshbuf_b64tod(decoded, (char *)sshbuf_ptr(encoded))) != 0)
+		goto out;
+
+	/* check magic */
+	if (sshbuf_len(decoded) < sizeof(AUTH_MAGIC) ||
+	    memcmp(sshbuf_ptr(decoded), AUTH_MAGIC, sizeof(AUTH_MAGIC))) {
+		r = SSH_ERR_INVALID_FORMAT;
+		goto out;
+	}
+	/* parse public portion of key */
+	if ((r = sshbuf_consume(decoded, sizeof(AUTH_MAGIC))) != 0 ||
+	    (r = sshbuf_get_cstring(decoded, &ciphername, NULL)) != 0 ||
+	    (r = sshbuf_get_cstring(decoded, &kdfname, NULL)) != 0 ||
+	    (r = sshbuf_froms(decoded, &kdf)) != 0 ||
+	    (r = sshbuf_get_u32(decoded, &nkeys)) != 0 ||
+	    (r = sshbuf_skip_string(decoded)) != 0 || /* pubkey */
+	    (r = sshbuf_get_u32(decoded, &encrypted_len)) != 0)
+		goto out;
+
+	if ((cipher = cipher_by_name(ciphername)) == NULL) {
+		r = SSH_ERR_KEY_UNKNOWN_CIPHER;
+		goto out;
+	}
+	if ((passphrase == NULL || strlen(passphrase) == 0) &&
+	    strcmp(ciphername, "none") != 0) {
+		/* passphrase required */
+		r = SSH_ERR_KEY_WRONG_PASSPHRASE;
+		goto out;
+	}
+	if (strcmp(kdfname, "none") != 0 && strcmp(kdfname, "bcrypt") != 0) {
+		r = SSH_ERR_KEY_UNKNOWN_CIPHER;
+		goto out;
+	}
+	if (!strcmp(kdfname, "none") && strcmp(ciphername, "none") != 0) {
+		r = SSH_ERR_INVALID_FORMAT;
+		goto out;
+	}
+	if (nkeys != 1) {
+		/* XXX only one key supported */
+		r = SSH_ERR_INVALID_FORMAT;
+		goto out;
+	}
+
+	/* check size of encrypted key blob */
+	blocksize = cipher_blocksize(cipher);
+	if (encrypted_len < blocksize || (encrypted_len % blocksize) != 0) {
+		r = SSH_ERR_INVALID_FORMAT;
+		goto out;
+	}
+
+	/* setup key */
+	keylen = cipher_keylen(cipher);
+	ivlen = cipher_ivlen(cipher);
+	authlen = cipher_authlen(cipher);
+	if ((key = calloc(1, keylen + ivlen)) == NULL) {
+		r = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+	if (strcmp(kdfname, "bcrypt") == 0) {
+		if ((r = sshbuf_get_string(kdf, &salt, &slen)) != 0 ||
+		    (r = sshbuf_get_u32(kdf, &rounds)) != 0)
+			goto out;
+		if (bcrypt_pbkdf(passphrase, strlen(passphrase), salt, slen,
+		    key, keylen + ivlen, rounds) < 0) {
+			r = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+	}
+
+	/* check that an appropriate amount of auth data is present */
+	if (sshbuf_len(decoded) < encrypted_len + authlen) {
+		r = SSH_ERR_INVALID_FORMAT;
+		goto out;
+	}
+
+	/* decrypt private portion of key */
+	if ((r = sshbuf_reserve(decrypted, encrypted_len, &dp)) != 0 ||
+	    (r = cipher_init(&ciphercontext, cipher, key, keylen,
+	    key + keylen, ivlen, 0)) != 0)
+		goto out;
+	if ((r = cipher_crypt(ciphercontext, 0, dp, sshbuf_ptr(decoded),
+	    encrypted_len, 0, authlen)) != 0) {
+		/* an integrity error here indicates an incorrect passphrase */
+		if (r == SSH_ERR_MAC_INVALID)
+			r = SSH_ERR_KEY_WRONG_PASSPHRASE;
+		goto out;
+	}
+	if ((r = sshbuf_consume(decoded, encrypted_len + authlen)) != 0)
+		goto out;
+	/* there should be no trailing data */
+	if (sshbuf_len(decoded) != 0) {
+		r = SSH_ERR_INVALID_FORMAT;
+		goto out;
+	}
+
+	/* check check bytes */
+	if ((r = sshbuf_get_u32(decrypted, &check1)) != 0 ||
+	    (r = sshbuf_get_u32(decrypted, &check2)) != 0)
+		goto out;
+	if (check1 != check2) {
+		r = SSH_ERR_KEY_WRONG_PASSPHRASE;
+		goto out;
+	}
+
+	/* Load the private key and comment */
+	if ((r = sshkey_private_deserialize(decrypted, &k)) != 0 ||
+	    (r = sshbuf_get_cstring(decrypted, &comment, NULL)) != 0)
+		goto out;
+
+	/* Check deterministic padding */
+	i = 0;
+	while (sshbuf_len(decrypted)) {
+		if ((r = sshbuf_get_u8(decrypted, &pad)) != 0)
+			goto out;
+		if (pad != (++i & 0xff)) {
+			r = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+	}
+
+	/* XXX decode pubkey and check against private */
+
+	/* success */
+	r = 0;
+	if (keyp != NULL) {
+		*keyp = k;
+		k = NULL;
+	}
+	if (commentp != NULL) {
+		*commentp = comment;
+		comment = NULL;
+	}
+ out:
+	pad = 0;
+	cipher_free(ciphercontext);
+	free(ciphername);
+	free(kdfname);
+	free(comment);
+	if (salt != NULL) {
+		explicit_bzero(salt, slen);
+		free(salt);
+	}
+	if (key != NULL) {
+		explicit_bzero(key, keylen + ivlen);
+		free(key);
+	}
+	sshbuf_free(encoded);
+	sshbuf_free(decoded);
+	sshbuf_free(kdf);
+	sshbuf_free(decrypted);
+	sshkey_free(k);
+	return r;
+}
+
+
+#ifdef WITH_OPENSSL
+/* convert SSH v2 key in OpenSSL PEM format */
+static int
+sshkey_private_pem_to_blob(struct sshkey *key, struct sshbuf *blob,
+    const char *_passphrase, const char *comment)
+{
+	int success, r;
+	int blen, len = strlen(_passphrase);
+	u_char *passphrase = (len > 0) ? (u_char *)_passphrase : NULL;
+	const EVP_CIPHER *cipher = (len > 0) ? EVP_aes_128_cbc() : NULL;
+	char *bptr;
+	BIO *bio = NULL;
+
+	if (len > 0 && len <= 4)
+		return SSH_ERR_PASSPHRASE_TOO_SHORT;
+	if ((bio = BIO_new(BIO_s_mem())) == NULL)
+		return SSH_ERR_ALLOC_FAIL;
+
+	switch (key->type) {
+	case KEY_DSA:
+		success = PEM_write_bio_DSAPrivateKey(bio, key->dsa,
+		    cipher, passphrase, len, NULL, NULL);
+		break;
+#ifdef OPENSSL_HAS_ECC
+	case KEY_ECDSA:
+		success = PEM_write_bio_ECPrivateKey(bio, key->ecdsa,
+		    cipher, passphrase, len, NULL, NULL);
+		break;
+#endif
+	case KEY_RSA:
+		success = PEM_write_bio_RSAPrivateKey(bio, key->rsa,
+		    cipher, passphrase, len, NULL, NULL);
+		break;
+	default:
+		success = 0;
+		break;
+	}
+	if (success == 0) {
+		r = SSH_ERR_LIBCRYPTO_ERROR;
+		goto out;
+	}
+	if ((blen = BIO_get_mem_data(bio, &bptr)) <= 0) {
+		r = SSH_ERR_INTERNAL_ERROR;
+		goto out;
+	}
+	if ((r = sshbuf_put(blob, bptr, blen)) != 0)
+		goto out;
+	r = 0;
+ out:
+	BIO_free(bio);
+	return r;
+}
+#endif /* WITH_OPENSSL */
+
+/* Serialise "key" to buffer "blob" */
+int
+sshkey_private_to_fileblob(struct sshkey *key, struct sshbuf *blob,
+    const char *passphrase, const char *comment,
+    int force_new_format, const char *new_format_cipher, int new_format_rounds)
+{
+	switch (key->type) {
+#ifdef WITH_OPENSSL
+	case KEY_DSA:
+	case KEY_ECDSA:
+	case KEY_RSA:
+		if (force_new_format) {
+			return sshkey_private_to_blob2(key, blob, passphrase,
+			    comment, new_format_cipher, new_format_rounds);
+		}
+		return sshkey_private_pem_to_blob(key, blob,
+		    passphrase, comment);
+#endif /* WITH_OPENSSL */
+	case KEY_ED25519:
+#ifdef WITH_XMSS
+	case KEY_XMSS:
+#endif /* WITH_XMSS */
+		return sshkey_private_to_blob2(key, blob, passphrase,
+		    comment, new_format_cipher, new_format_rounds);
+	default:
+		return SSH_ERR_KEY_TYPE_UNKNOWN;
+	}
+}
+
+
+#ifdef WITH_OPENSSL
+static int
+translate_libcrypto_error(unsigned long pem_err)
+{
+	int pem_reason = ERR_GET_REASON(pem_err);
+
+	switch (ERR_GET_LIB(pem_err)) {
+	case ERR_LIB_PEM:
+		switch (pem_reason) {
+		case PEM_R_BAD_PASSWORD_READ:
+		case PEM_R_PROBLEMS_GETTING_PASSWORD:
+		case PEM_R_BAD_DECRYPT:
+			return SSH_ERR_KEY_WRONG_PASSPHRASE;
+		default:
+			return SSH_ERR_INVALID_FORMAT;
+		}
+	case ERR_LIB_EVP:
+		switch (pem_reason) {
+		case EVP_R_BAD_DECRYPT:
+			return SSH_ERR_KEY_WRONG_PASSPHRASE;
+#ifdef EVP_R_BN_DECODE_ERROR
+		case EVP_R_BN_DECODE_ERROR:
+#endif
+		case EVP_R_DECODE_ERROR:
+#ifdef EVP_R_PRIVATE_KEY_DECODE_ERROR
+		case EVP_R_PRIVATE_KEY_DECODE_ERROR:
+#endif
+			return SSH_ERR_INVALID_FORMAT;
+		default:
+			return SSH_ERR_LIBCRYPTO_ERROR;
+		}
+	case ERR_LIB_ASN1:
+		return SSH_ERR_INVALID_FORMAT;
+	}
+	return SSH_ERR_LIBCRYPTO_ERROR;
+}
+
+static void
+clear_libcrypto_errors(void)
+{
+	while (ERR_get_error() != 0)
+		;
+}
+
+/*
+ * Translate OpenSSL error codes to determine whether
+ * passphrase is required/incorrect.
+ */
+static int
+convert_libcrypto_error(void)
+{
+	/*
+	 * Some password errors are reported at the beginning
+	 * of the error queue.
+	 */
+	if (translate_libcrypto_error(ERR_peek_error()) ==
+	    SSH_ERR_KEY_WRONG_PASSPHRASE)
+		return SSH_ERR_KEY_WRONG_PASSPHRASE;
+	return translate_libcrypto_error(ERR_peek_last_error());
+}
+
+static int
+pem_passphrase_cb(char *buf, int size, int rwflag, void *u)
+{
+	char *p = (char *)u;
+	size_t len;
+
+	if (p == NULL || (len = strlen(p)) == 0)
+		return -1;
+	if (size < 0 || len > (size_t)size)
+		return -1;
+	memcpy(buf, p, len);
+	return (int)len;
+}
+
+static int
+sshkey_parse_private_pem_fileblob(struct sshbuf *blob, int type,
+    const char *passphrase, struct sshkey **keyp)
+{
+	EVP_PKEY *pk = NULL;
+	struct sshkey *prv = NULL;
+	BIO *bio = NULL;
+	int r;
+
+	if (keyp != NULL)
+		*keyp = NULL;
+
+	if ((bio = BIO_new(BIO_s_mem())) == NULL || sshbuf_len(blob) > INT_MAX)
+		return SSH_ERR_ALLOC_FAIL;
+	if (BIO_write(bio, sshbuf_ptr(blob), sshbuf_len(blob)) !=
+	    (int)sshbuf_len(blob)) {
+		r = SSH_ERR_ALLOC_FAIL;
+		goto out;
+	}
+
+	clear_libcrypto_errors();
+	if ((pk = PEM_read_bio_PrivateKey(bio, NULL, pem_passphrase_cb,
+	    (char *)passphrase)) == NULL) {
+	       /*
+		* libcrypto may return various ASN.1 errors when attempting
+		* to parse a key with an incorrect passphrase.
+		* Treat all format errors as "incorrect passphrase" if a
+		* passphrase was supplied.
+		*/
+		if (passphrase != NULL && *passphrase != '\0')
+			r = SSH_ERR_KEY_WRONG_PASSPHRASE;
+		else
+			r = convert_libcrypto_error();
+		goto out;
+	}
+	if (EVP_PKEY_base_id(pk) == EVP_PKEY_RSA &&
+	    (type == KEY_UNSPEC || type == KEY_RSA)) {
+		if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		prv->rsa = EVP_PKEY_get1_RSA(pk);
+		prv->type = KEY_RSA;
+#ifdef DEBUG_PK
+		RSA_print_fp(stderr, prv->rsa, 8);
+#endif
+		if (RSA_blinding_on(prv->rsa, NULL) != 1) {
+			r = SSH_ERR_LIBCRYPTO_ERROR;
+			goto out;
+		}
+		if ((r = check_rsa_length(prv->rsa)) != 0)
+			goto out;
+	} else if (EVP_PKEY_base_id(pk) == EVP_PKEY_DSA &&
+	    (type == KEY_UNSPEC || type == KEY_DSA)) {
+		if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		prv->dsa = EVP_PKEY_get1_DSA(pk);
+		prv->type = KEY_DSA;
+#ifdef DEBUG_PK
+		DSA_print_fp(stderr, prv->dsa, 8);
+#endif
+#ifdef OPENSSL_HAS_ECC
+	} else if (EVP_PKEY_base_id(pk) == EVP_PKEY_EC &&
+	    (type == KEY_UNSPEC || type == KEY_ECDSA)) {
+		if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) {
+			r = SSH_ERR_ALLOC_FAIL;
+			goto out;
+		}
+		prv->ecdsa = EVP_PKEY_get1_EC_KEY(pk);
+		prv->type = KEY_ECDSA;
+		prv->ecdsa_nid = sshkey_ecdsa_key_to_nid(prv->ecdsa);
+		if (prv->ecdsa_nid == -1 ||
+		    sshkey_curve_nid_to_name(prv->ecdsa_nid) == NULL ||
+		    sshkey_ec_validate_public(EC_KEY_get0_group(prv->ecdsa),
+		    EC_KEY_get0_public_key(prv->ecdsa)) != 0 ||
+		    sshkey_ec_validate_private(prv->ecdsa) != 0) {
+			r = SSH_ERR_INVALID_FORMAT;
+			goto out;
+		}
+# ifdef DEBUG_PK
+		if (prv != NULL && prv->ecdsa != NULL)
+			sshkey_dump_ec_key(prv->ecdsa);
+# endif
+#endif /* OPENSSL_HAS_ECC */
+	} else {
+		r = SSH_ERR_INVALID_FORMAT;
+		goto out;
+	}
+	r = 0;
+	if (keyp != NULL) {
+		*keyp = prv;
+		prv = NULL;
+	}
+ out:
+	BIO_free(bio);
+	EVP_PKEY_free(pk);
+	sshkey_free(prv);
+	return r;
+}
+#endif /* WITH_OPENSSL */
+
+int
+sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type,
+    const char *passphrase, struct sshkey **keyp, char **commentp)
+{
+	int r = SSH_ERR_INTERNAL_ERROR;
+
+	if (keyp != NULL)
+		*keyp = NULL;
+	if (commentp != NULL)
+		*commentp = NULL;
+
+	switch (type) {
+#ifdef WITH_OPENSSL
+	case KEY_DSA:
+	case KEY_ECDSA:
+	case KEY_RSA:
+		return sshkey_parse_private_pem_fileblob(blob, type,
+		    passphrase, keyp);
+#endif /* WITH_OPENSSL */
+	case KEY_ED25519:
+#ifdef WITH_XMSS
+	case KEY_XMSS:
+#endif /* WITH_XMSS */
+		return sshkey_parse_private2(blob, type, passphrase,
+		    keyp, commentp);
+	case KEY_UNSPEC:
+		r = sshkey_parse_private2(blob, type, passphrase, keyp,
+		    commentp);
+		/* Do not fallback to PEM parser if only passphrase is wrong. */
+		if (r == 0 || r == SSH_ERR_KEY_WRONG_PASSPHRASE)
+			return r;
+#ifdef WITH_OPENSSL
+		return sshkey_parse_private_pem_fileblob(blob, type,
+		    passphrase, keyp);
+#else
+		return SSH_ERR_INVALID_FORMAT;
+#endif /* WITH_OPENSSL */
+	default:
+		return SSH_ERR_KEY_TYPE_UNKNOWN;
+	}
+}
+
+int
+sshkey_parse_private_fileblob(struct sshbuf *buffer, const char *passphrase,
+    struct sshkey **keyp, char **commentp)
+{
+	if (keyp != NULL)
+		*keyp = NULL;
+	if (commentp != NULL)
+		*commentp = NULL;
+
+	return sshkey_parse_private_fileblob_type(buffer, KEY_UNSPEC,
+	    passphrase, keyp, commentp);
+}
+
+#ifdef WITH_XMSS
+/*
+ * serialize the key with the current state and forward the state
+ * maxsign times.
+ */
+int
+sshkey_private_serialize_maxsign(const struct sshkey *k, struct sshbuf *b,
+    u_int32_t maxsign, sshkey_printfn *pr)
+{
+	int r, rupdate;
+
+	if (maxsign == 0 ||
+	    sshkey_type_plain(k->type) != KEY_XMSS)
+		return sshkey_private_serialize_opt(k, b,
+		    SSHKEY_SERIALIZE_DEFAULT);
+	if ((r = sshkey_xmss_get_state(k, pr)) != 0 ||
+	    (r = sshkey_private_serialize_opt(k, b,
+	    SSHKEY_SERIALIZE_STATE)) != 0 ||
+	    (r = sshkey_xmss_forward_state(k, maxsign)) != 0)
+		goto out;
+	r = 0;
+out:
+	if ((rupdate = sshkey_xmss_update_state(k, pr)) != 0) {
+		if (r == 0)
+			r = rupdate;
+	}
+	return r;
+}
+
+u_int32_t
+sshkey_signatures_left(const struct sshkey *k)
+{
+	if (sshkey_type_plain(k->type) == KEY_XMSS)
+		return sshkey_xmss_signatures_left(k);
+	return 0;
+}
+
+int
+sshkey_enable_maxsign(struct sshkey *k, u_int32_t maxsign)
+{
+	if (sshkey_type_plain(k->type) != KEY_XMSS)
+		return SSH_ERR_INVALID_ARGUMENT;
+	return sshkey_xmss_enable_maxsign(k, maxsign);
+}
+
+int
+sshkey_set_filename(struct sshkey *k, const char *filename)
+{
+	if (k == NULL)
+		return SSH_ERR_INVALID_ARGUMENT;
+	if (sshkey_type_plain(k->type) != KEY_XMSS)
+		return 0;
+	if (filename == NULL)
+		return SSH_ERR_INVALID_ARGUMENT;
+	if ((k->xmss_filename = strdup(filename)) == NULL)
+		return SSH_ERR_ALLOC_FAIL;
+	return 0;
+}
+#else
+int
+sshkey_private_serialize_maxsign(const struct sshkey *k, struct sshbuf *b,
+    u_int32_t maxsign, sshkey_printfn *pr)
+{
+	return sshkey_private_serialize_opt(k, b, SSHKEY_SERIALIZE_DEFAULT);
+}
+
+u_int32_t
+sshkey_signatures_left(const struct sshkey *k)
+{
+	return 0;
+}
+
+int
+sshkey_enable_maxsign(struct sshkey *k, u_int32_t maxsign)
+{
+	return SSH_ERR_INVALID_ARGUMENT;
+}
+
+int
+sshkey_set_filename(struct sshkey *k, const char *filename)
+{
+	if (k == NULL)
+		return SSH_ERR_INVALID_ARGUMENT;
+	return 0;
+}
+#endif /* WITH_XMSS */