From: djm <djm@openbsd.org>
Date: Thu, 9 Jan 2014 23:20:00 +0000 (+0000)
Subject: Introduce digest API and use it to perform all hashing operations
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=8df5df93ec0c8b5c8a3f94bd81f484198667d804;p=openbsd

Introduce digest API and use it to perform all hashing operations
rather than calling OpenSSL EVP_Digest* directly. Will make it easier
to build a reduced-feature OpenSSH without OpenSSL in future;
feedback, ok markus@
---

diff --git a/usr.bin/ssh/digest.c b/usr.bin/ssh/digest.c
new file mode 100644
index 00000000000..667d3d948c0
--- /dev/null
+++ b/usr.bin/ssh/digest.c
@@ -0,0 +1,144 @@
+/* $OpenBSD: digest.c,v 1.1 2014/01/09 23:20:00 djm Exp $ */
+/*
+ * Copyright (c) 2013 Damien Miller <djm@mindrot.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <openssl/bn.h> /* for buffer.h */
+#include <openssl/ec.h> /* for buffer.h */
+#include <openssl/evp.h>
+
+#include "buffer.h"
+#include "digest.h"
+
+struct ssh_digest_ctx {
+	int alg;
+	EVP_MD_CTX mdctx;
+};
+
+struct ssh_digest {
+	int id;
+	const char *name;
+	size_t digest_len;
+	const EVP_MD *(*mdfunc)(void);
+};
+
+/* NB. Indexed directly by algorithm number */
+const struct ssh_digest digests[] = {
+	{ SSH_DIGEST_MD5,	"MD5",	 	16,	EVP_md5 },
+	{ SSH_DIGEST_RIPEMD160,	"RIPEMD160",	20,	EVP_ripemd160 },
+	{ SSH_DIGEST_SHA1,	"SHA1",	 	20,	EVP_sha1 },
+	{ SSH_DIGEST_SHA256,	"SHA256", 	32,	EVP_sha256 },
+	{ SSH_DIGEST_SHA384,	"SHA384",	48,	EVP_sha384 },
+	{ SSH_DIGEST_SHA512,	"SHA512", 	64,	EVP_sha512 },
+	{ -1,			NULL,		0,	NULL },
+};
+
+static const struct ssh_digest *
+ssh_digest_by_alg(int alg)
+{
+	if (alg < 0 || alg >= SSH_DIGEST_MAX)
+		return NULL;
+	if (digests[alg].id != alg) /* sanity */
+		return NULL;
+	return &(digests[alg]);
+}
+
+size_t
+ssh_digest_bytes(int alg)
+{
+	const struct ssh_digest *digest = ssh_digest_by_alg(alg);
+
+	return digest == NULL ? 0 : digest->digest_len;
+}
+
+struct ssh_digest_ctx *
+ssh_digest_start(int alg)
+{
+	const struct ssh_digest *digest = ssh_digest_by_alg(alg);
+	struct ssh_digest_ctx *ret;
+
+	if (digest == NULL || ((ret = calloc(1, sizeof(*ret))) == NULL))
+		return NULL;
+	ret->alg = alg;
+	EVP_MD_CTX_init(&ret->mdctx);
+	if (EVP_DigestInit_ex(&ret->mdctx, digest->mdfunc(), NULL) != 1) {
+		free(ret);
+		return NULL;
+	}
+	return ret;
+}
+
+int
+ssh_digest_update(struct ssh_digest_ctx *ctx, const void *m, size_t mlen)
+{
+	if (EVP_DigestUpdate(&ctx->mdctx, m, mlen) != 1)
+		return -1;
+	return 0;
+}
+
+int
+ssh_digest_update_buffer(struct ssh_digest_ctx *ctx, const Buffer *b)
+{
+	return ssh_digest_update(ctx, buffer_ptr(b), buffer_len(b));
+}
+
+int
+ssh_digest_final(struct ssh_digest_ctx *ctx, u_char *d, size_t dlen)
+{
+	const struct ssh_digest *digest = ssh_digest_by_alg(ctx->alg);
+	u_int l = dlen;
+
+	if (dlen > UINT_MAX)
+		return -1;
+	if (dlen < digest->digest_len) /* No truncation allowed */
+		return -1;
+	if (EVP_DigestFinal_ex(&ctx->mdctx, d, &l) != 1)
+		return -1;
+	if (l != digest->digest_len) /* sanity */
+		return -1;
+	return 0;
+}
+
+void
+ssh_digest_free(struct ssh_digest_ctx *ctx)
+{
+	EVP_MD_CTX_cleanup(&ctx->mdctx);
+	memset(ctx, 0, sizeof(*ctx));
+}
+
+int
+ssh_digest_memory(int alg, const void *m, size_t mlen, u_char *d, size_t dlen)
+{
+	struct ssh_digest_ctx *ctx = ssh_digest_start(alg);
+
+	if (ctx == NULL)
+		return -1;
+	if (ssh_digest_update(ctx, m, mlen) != 0 ||
+	    ssh_digest_final(ctx, d, dlen) != 0)
+		return -1;
+	ssh_digest_free(ctx);
+	return 0;
+}
+
+int
+ssh_digest_buffer(int alg, const Buffer *b, u_char *d, size_t dlen)
+{
+	return ssh_digest_memory(alg, buffer_ptr(b), buffer_len(b), d, dlen);
+}
diff --git a/usr.bin/ssh/digest.h b/usr.bin/ssh/digest.h
new file mode 100644
index 00000000000..faefda3f533
--- /dev/null
+++ b/usr.bin/ssh/digest.h
@@ -0,0 +1,55 @@
+/* $OpenBSD: digest.h,v 1.1 2014/01/09 23:20:00 djm Exp $ */
+/*
+ * Copyright (c) 2013 Damien Miller <djm@mindrot.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef _DIGEST_H
+#define _DIGEST_H
+
+/* Maximum digest output length */
+#define SSH_DIGEST_MAX_LENGTH	64
+
+/* Digest algorithms */
+#define SSH_DIGEST_MD5		0
+#define SSH_DIGEST_RIPEMD160	1
+#define SSH_DIGEST_SHA1		2
+#define SSH_DIGEST_SHA256	3
+#define SSH_DIGEST_SHA384	4
+#define SSH_DIGEST_SHA512	5
+#define SSH_DIGEST_MAX		6
+
+/* Returns the algorithm's digest length in bytes or 0 for invalid algorithm */
+size_t ssh_digest_bytes(int alg);
+
+/* One-shot API */
+int ssh_digest_memory(int alg, const void *m, size_t mlen,
+    u_char *d, size_t dlen)
+	__attribute__((__bounded__(__buffer__, 2, 3)))
+	__attribute__((__bounded__(__buffer__, 4, 5)));
+int ssh_digest_buffer(int alg, const Buffer *b, u_char *d, size_t dlen)
+	__attribute__((__bounded__(__buffer__, 3, 4)));
+
+/* Update API */
+struct ssh_digest_ctx;
+struct ssh_digest_ctx *ssh_digest_start(int alg);
+int ssh_digest_update(struct ssh_digest_ctx *ctx, const void *m, size_t mlen)
+	__attribute__((__bounded__(__buffer__, 2, 3)));
+int ssh_digest_update_buffer(struct ssh_digest_ctx *ctx, const Buffer *b);
+int ssh_digest_final(struct ssh_digest_ctx *ctx, u_char *d, size_t dlen)
+	__attribute__((__bounded__(__buffer__, 2, 3)));
+void ssh_digest_free(struct ssh_digest_ctx *ctx);
+
+#endif /* _DIGEST_H */
+
diff --git a/usr.bin/ssh/hostfile.c b/usr.bin/ssh/hostfile.c
index 0ebc82757ee..8225711a43c 100644
--- a/usr.bin/ssh/hostfile.c
+++ b/usr.bin/ssh/hostfile.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: hostfile.c,v 1.52 2013/07/12 00:19:58 djm Exp $ */
+/* $OpenBSD: hostfile.c,v 1.53 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -54,6 +54,7 @@
 #include "hostfile.h"
 #include "log.h"
 #include "misc.h"
+#include "digest.h"
 
 struct hostkeys {
 	struct hostkey_entry *entries;
diff --git a/usr.bin/ssh/kex.c b/usr.bin/ssh/kex.c
index 8d568006620..a85347666bf 100644
--- a/usr.bin/ssh/kex.c
+++ b/usr.bin/ssh/kex.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kex.c,v 1.93 2013/11/07 11:58:27 dtucker Exp $ */
+/* $OpenBSD: kex.c,v 1.94 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
  *
@@ -46,6 +46,7 @@
 #include "dispatch.h"
 #include "monitor.h"
 #include "roaming.h"
+#include "digest.h"
 
 /* prototype */
 static void kex_kexinit_finish(Kex *);
@@ -55,18 +56,21 @@ struct kexalg {
 	char *name;
 	int type;
 	int ec_nid;
-	const EVP_MD *(*mdfunc)(void);
+	int hash_alg;
 };
 static const struct kexalg kexalgs[] = {
-	{ KEX_DH1, KEX_DH_GRP1_SHA1, 0, EVP_sha1 },
-	{ KEX_DH14, KEX_DH_GRP14_SHA1, 0, EVP_sha1 },
-	{ KEX_DHGEX_SHA1, KEX_DH_GEX_SHA1, 0, EVP_sha1 },
-	{ KEX_DHGEX_SHA256, KEX_DH_GEX_SHA256, 0, EVP_sha256 },
-	{ KEX_ECDH_SHA2_NISTP256, KEX_ECDH_SHA2, NID_X9_62_prime256v1, EVP_sha256 },
-	{ KEX_ECDH_SHA2_NISTP384, KEX_ECDH_SHA2, NID_secp384r1, EVP_sha384 },
-	{ KEX_ECDH_SHA2_NISTP521, KEX_ECDH_SHA2, NID_secp521r1, EVP_sha512 },
-	{ KEX_CURVE25519_SHA256, KEX_C25519_SHA256, 0, EVP_sha256 },
-	{ NULL, -1, -1, NULL},
+	{ KEX_DH1, KEX_DH_GRP1_SHA1, 0, SSH_DIGEST_SHA1 },
+	{ KEX_DH14, KEX_DH_GRP14_SHA1, 0, SSH_DIGEST_SHA1 },
+	{ KEX_DHGEX_SHA1, KEX_DH_GEX_SHA1, 0, SSH_DIGEST_SHA1 },
+	{ KEX_DHGEX_SHA256, KEX_DH_GEX_SHA256, 0, SSH_DIGEST_SHA256 },
+	{ KEX_ECDH_SHA2_NISTP256, KEX_ECDH_SHA2,
+	    NID_X9_62_prime256v1, SSH_DIGEST_SHA256 },
+	{ KEX_ECDH_SHA2_NISTP384, KEX_ECDH_SHA2, NID_secp384r1,
+	    SSH_DIGEST_SHA384 },
+	{ KEX_ECDH_SHA2_NISTP521, KEX_ECDH_SHA2, NID_secp521r1,
+	    SSH_DIGEST_SHA512 },
+	{ KEX_CURVE25519_SHA256, KEX_C25519_SHA256, 0, SSH_DIGEST_SHA256 },
+	{ NULL, -1, -1, -1},
 };
 
 char *
@@ -387,7 +391,7 @@ choose_kex(Kex *k, char *client, char *server)
 	if ((kexalg = kex_alg_by_name(k->name)) == NULL)
 		fatal("unsupported kex alg %s", k->name);
 	k->kex_type = kexalg->type;
-	k->evp_md = kexalg->mdfunc();
+	k->hash_alg = kexalg->hash_alg;
 	k->ec_nid = kexalg->ec_nid;
 }
 
@@ -513,27 +517,31 @@ derive_key(Kex *kex, int id, u_int need, u_char *hash, u_int hashlen,
     BIGNUM *shared_secret)
 {
 	Buffer b;
-	EVP_MD_CTX md;
+	struct ssh_digest_ctx *hashctx;
 	char c = id;
 	u_int have;
-	int mdsz;
+	size_t mdsz;
 	u_char *digest;
 
-	if ((mdsz = EVP_MD_size(kex->evp_md)) <= 0)
-		fatal("bad kex md size %d", mdsz);
+	if ((mdsz = ssh_digest_bytes(kex->hash_alg)) == 0)
+		fatal("bad kex md size %zu", mdsz);
 	digest = xmalloc(roundup(need, mdsz));
 
 	buffer_init(&b);
 	buffer_put_bignum2(&b, shared_secret);
 
 	/* K1 = HASH(K || H || "A" || session_id) */
-	EVP_DigestInit(&md, kex->evp_md);
-	if (!(datafellows & SSH_BUG_DERIVEKEY))
-		EVP_DigestUpdate(&md, buffer_ptr(&b), buffer_len(&b));
-	EVP_DigestUpdate(&md, hash, hashlen);
-	EVP_DigestUpdate(&md, &c, 1);
-	EVP_DigestUpdate(&md, kex->session_id, kex->session_id_len);
-	EVP_DigestFinal(&md, digest, NULL);
+	if ((hashctx = ssh_digest_start(kex->hash_alg)) == NULL)
+		fatal("%s: ssh_digest_start failed", __func__);
+	if (ssh_digest_update_buffer(hashctx, &b) != 0 ||
+	    ssh_digest_update(hashctx, hash, hashlen) != 0 ||
+	    ssh_digest_update(hashctx, &c, 1) != 0 ||
+	    ssh_digest_update(hashctx, kex->session_id,
+	    kex->session_id_len) != 0)
+		fatal("%s: ssh_digest_update failed", __func__);
+	if (ssh_digest_final(hashctx, digest, mdsz) != 0)
+		fatal("%s: ssh_digest_final failed", __func__);
+	ssh_digest_free(hashctx);
 
 	/*
 	 * expand key:
@@ -541,12 +549,15 @@ derive_key(Kex *kex, int id, u_int need, u_char *hash, u_int hashlen,
 	 * Key = K1 || K2 || ... || Kn
 	 */
 	for (have = mdsz; need > have; have += mdsz) {
-		EVP_DigestInit(&md, kex->evp_md);
-		if (!(datafellows & SSH_BUG_DERIVEKEY))
-			EVP_DigestUpdate(&md, buffer_ptr(&b), buffer_len(&b));
-		EVP_DigestUpdate(&md, hash, hashlen);
-		EVP_DigestUpdate(&md, digest, have);
-		EVP_DigestFinal(&md, digest + have, NULL);
+		if ((hashctx = ssh_digest_start(kex->hash_alg)) == NULL)
+			fatal("%s: ssh_digest_start failed", __func__);
+		if (ssh_digest_update_buffer(hashctx, &b) != 0 ||
+		    ssh_digest_update(hashctx, hash, hashlen) != 0 ||
+		    ssh_digest_update(hashctx, digest, have) != 0)
+			fatal("%s: ssh_digest_update failed", __func__);
+		if (ssh_digest_final(hashctx, digest + have, mdsz) != 0)
+			fatal("%s: ssh_digest_final failed", __func__);
+		ssh_digest_free(hashctx);
 	}
 	buffer_free(&b);
 #ifdef DEBUG_KEX
@@ -596,33 +607,33 @@ void
 derive_ssh1_session_id(BIGNUM *host_modulus, BIGNUM *server_modulus,
     u_int8_t cookie[8], u_int8_t id[16])
 {
-	const EVP_MD *evp_md = EVP_md5();
-	EVP_MD_CTX md;
-	u_int8_t nbuf[2048], obuf[EVP_MAX_MD_SIZE];
+	u_int8_t nbuf[2048], obuf[SSH_DIGEST_MAX_LENGTH];
 	int len;
+	struct ssh_digest_ctx *hashctx;
 
-	EVP_DigestInit(&md, evp_md);
+	if ((hashctx = ssh_digest_start(SSH_DIGEST_MD5)) == NULL)
+		fatal("%s: ssh_digest_start", __func__);
 
 	len = BN_num_bytes(host_modulus);
 	if (len < (512 / 8) || (u_int)len > sizeof(nbuf))
 		fatal("%s: bad host modulus (len %d)", __func__, len);
 	BN_bn2bin(host_modulus, nbuf);
-	EVP_DigestUpdate(&md, nbuf, len);
+	if (ssh_digest_update(hashctx, nbuf, len) != 0)
+		fatal("%s: ssh_digest_update failed", __func__);
 
 	len = BN_num_bytes(server_modulus);
 	if (len < (512 / 8) || (u_int)len > sizeof(nbuf))
 		fatal("%s: bad server modulus (len %d)", __func__, len);
 	BN_bn2bin(server_modulus, nbuf);
-	EVP_DigestUpdate(&md, nbuf, len);
-
-	EVP_DigestUpdate(&md, cookie, 8);
-
-	EVP_DigestFinal(&md, obuf, NULL);
-	memcpy(id, obuf, 16);
+	if (ssh_digest_update(hashctx, nbuf, len) != 0 ||
+	    ssh_digest_update(hashctx, cookie, 8) != 0)
+		fatal("%s: ssh_digest_update failed", __func__);
+	if (ssh_digest_final(hashctx, obuf, sizeof(obuf)) != 0)
+		fatal("%s: ssh_digest_final failed", __func__);
+	memcpy(id, obuf, ssh_digest_bytes(SSH_DIGEST_MD5));
 
 	memset(nbuf, 0, sizeof(nbuf));
 	memset(obuf, 0, sizeof(obuf));
-	memset(&md, 0, sizeof(md));
 }
 
 #if defined(DEBUG_KEX) || defined(DEBUG_KEXDH) || defined(DEBUG_KEXECDH)
diff --git a/usr.bin/ssh/kex.h b/usr.bin/ssh/kex.h
index b8a889f5401..612b9503943 100644
--- a/usr.bin/ssh/kex.h
+++ b/usr.bin/ssh/kex.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: kex.h,v 1.58 2013/11/07 11:58:27 dtucker Exp $ */
+/* $OpenBSD: kex.h,v 1.59 2014/01/09 23:20:00 djm Exp $ */
 
 /*
  * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
@@ -130,7 +130,7 @@ struct Kex {
 	Buffer	peer;
 	sig_atomic_t done;
 	int	flags;
-	const EVP_MD *evp_md;
+	int	hash_alg;
 	int	ec_nid;
 	char	*client_version_string;
 	char	*server_version_string;
@@ -167,15 +167,15 @@ void
 kex_dh_hash(char *, char *, char *, int, char *, int, u_char *, int,
     BIGNUM *, BIGNUM *, BIGNUM *, u_char **, u_int *);
 void
-kexgex_hash(const EVP_MD *, char *, char *, char *, int, char *,
+kexgex_hash(int, char *, char *, char *, int, char *,
     int, u_char *, int, int, int, int, BIGNUM *, BIGNUM *, BIGNUM *,
     BIGNUM *, BIGNUM *, u_char **, u_int *);
 void
-kex_ecdh_hash(const EVP_MD *, const EC_GROUP *, char *, char *, char *, int,
+kex_ecdh_hash(int, const EC_GROUP *, char *, char *, char *, int,
     char *, int, u_char *, int, const EC_POINT *, const EC_POINT *,
     const BIGNUM *, u_char **, u_int *);
 void
-kex_c25519_hash(const EVP_MD *, char *, char *, char *, int,
+kex_c25519_hash(int, char *, char *, char *, int,
     char *, int, u_char *, int, const u_char *, const u_char *,
     const BIGNUM *, u_char **, u_int *);
 
diff --git a/usr.bin/ssh/kexc25519.c b/usr.bin/ssh/kexc25519.c
index df80cf9b16e..22c705205a1 100644
--- a/usr.bin/ssh/kexc25519.c
+++ b/usr.bin/ssh/kexc25519.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexc25519.c,v 1.2 2013/11/02 22:02:14 markus Exp $ */
+/* $OpenBSD: kexc25519.c,v 1.3 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2001, 2013 Markus Friedl.  All rights reserved.
  * Copyright (c) 2010 Damien Miller.  All rights reserved.
@@ -39,6 +39,7 @@
 #include "cipher.h"
 #include "kex.h"
 #include "log.h"
+#include "digest.h"
 
 extern int crypto_scalarmult_curve25519(u_char a[CURVE25519_SIZE],
     const u_char b[CURVE25519_SIZE], const u_char c[CURVE25519_SIZE])
@@ -76,7 +77,7 @@ kexc25519_shared_key(const u_char key[CURVE25519_SIZE],
 
 void
 kex_c25519_hash(
-    const EVP_MD *evp_md,
+    int hash_alg,
     char *client_version_string,
     char *server_version_string,
     char *ckexinit, int ckexinitlen,
@@ -88,8 +89,7 @@ kex_c25519_hash(
     u_char **hash, u_int *hashlen)
 {
 	Buffer b;
-	EVP_MD_CTX md;
-	static u_char digest[EVP_MAX_MD_SIZE];
+	static u_char digest[SSH_DIGEST_MAX_LENGTH];
 
 	buffer_init(&b);
 	buffer_put_cstring(&b, client_version_string);
@@ -111,15 +111,14 @@ kex_c25519_hash(
 #ifdef DEBUG_KEX
 	buffer_dump(&b);
 #endif
-	EVP_DigestInit(&md, evp_md);
-	EVP_DigestUpdate(&md, buffer_ptr(&b), buffer_len(&b));
-	EVP_DigestFinal(&md, digest, NULL);
+	if (ssh_digest_buffer(hash_alg, &b, digest, sizeof(digest)) != 0)
+		fatal("%s: digest_buffer failed", __func__);
 
 	buffer_free(&b);
 
 #ifdef DEBUG_KEX
-	dump_digest("hash", digest, EVP_MD_size(evp_md));
+	dump_digest("hash", digest, ssh_digest_bytes(hash_alg));
 #endif
 	*hash = digest;
-	*hashlen = EVP_MD_size(evp_md);
+	*hashlen = ssh_digest_bytes(hash_alg);
 }
diff --git a/usr.bin/ssh/kexc25519c.c b/usr.bin/ssh/kexc25519c.c
index cc68c0c6477..5d7d31e6eb8 100644
--- a/usr.bin/ssh/kexc25519c.c
+++ b/usr.bin/ssh/kexc25519c.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexc25519c.c,v 1.2 2013/11/02 22:02:14 markus Exp $ */
+/* $OpenBSD: kexc25519c.c,v 1.3 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  * Copyright (c) 2010 Damien Miller.  All rights reserved.
@@ -95,7 +95,7 @@ kexc25519_client(Kex *kex)
 
 	/* calc and verify H */
 	kex_c25519_hash(
-	    kex->evp_md,
+	    kex->hash_alg,
 	    kex->client_version_string,
 	    kex->server_version_string,
 	    buffer_ptr(&kex->my), buffer_len(&kex->my),
diff --git a/usr.bin/ssh/kexc25519s.c b/usr.bin/ssh/kexc25519s.c
index 22d84b17f0d..8de3f0acee9 100644
--- a/usr.bin/ssh/kexc25519s.c
+++ b/usr.bin/ssh/kexc25519s.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexc25519s.c,v 1.2 2013/11/02 22:02:14 markus Exp $ */
+/* $OpenBSD: kexc25519s.c,v 1.3 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  * Copyright (c) 2010 Damien Miller.  All rights reserved.
@@ -79,7 +79,7 @@ kexc25519_server(Kex *kex)
 	/* calc H */
 	key_to_blob(server_host_public, &server_host_key_blob, &sbloblen);
 	kex_c25519_hash(
-	    kex->evp_md,
+	    kex->hash_alg,
 	    kex->client_version_string,
 	    kex->server_version_string,
 	    buffer_ptr(&kex->peer), buffer_len(&kex->peer),
diff --git a/usr.bin/ssh/kexdh.c b/usr.bin/ssh/kexdh.c
index 8e6ae6348e4..f750dc79ac1 100644
--- a/usr.bin/ssh/kexdh.c
+++ b/usr.bin/ssh/kexdh.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexdh.c,v 1.23 2006/08/03 03:34:42 deraadt Exp $ */
+/* $OpenBSD: kexdh.c,v 1.24 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  *
@@ -34,6 +34,8 @@
 #include "key.h"
 #include "cipher.h"
 #include "kex.h"
+#include "digest.h"
+#include "log.h"
 
 void
 kex_dh_hash(
@@ -48,9 +50,7 @@ kex_dh_hash(
     u_char **hash, u_int *hashlen)
 {
 	Buffer b;
-	static u_char digest[EVP_MAX_MD_SIZE];
-	const EVP_MD *evp_md = EVP_sha1();
-	EVP_MD_CTX md;
+	static u_char digest[SSH_DIGEST_MAX_LENGTH];
 
 	buffer_init(&b);
 	buffer_put_cstring(&b, client_version_string);
@@ -72,15 +72,14 @@ kex_dh_hash(
 #ifdef DEBUG_KEX
 	buffer_dump(&b);
 #endif
-	EVP_DigestInit(&md, evp_md);
-	EVP_DigestUpdate(&md, buffer_ptr(&b), buffer_len(&b));
-	EVP_DigestFinal(&md, digest, NULL);
+	if (ssh_digest_buffer(SSH_DIGEST_SHA1, &b, digest, sizeof(digest)) != 0)
+		fatal("%s: ssh_digest_buffer failed", __func__);
 
 	buffer_free(&b);
 
 #ifdef DEBUG_KEX
-	dump_digest("hash", digest, EVP_MD_size(evp_md));
+	dump_digest("hash", digest, ssh_digest_bytes(SSH_DIGEST_SHA1));
 #endif
 	*hash = digest;
-	*hashlen = EVP_MD_size(evp_md);
+	*hashlen = ssh_digest_bytes(SSH_DIGEST_SHA1);
 }
diff --git a/usr.bin/ssh/kexecdh.c b/usr.bin/ssh/kexecdh.c
index 93d9b02c1ac..ba99f3db220 100644
--- a/usr.bin/ssh/kexecdh.c
+++ b/usr.bin/ssh/kexecdh.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexecdh.c,v 1.4 2013/04/19 01:06:50 djm Exp $ */
+/* $OpenBSD: kexecdh.c,v 1.5 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  * Copyright (c) 2010 Damien Miller.  All rights reserved.
@@ -40,10 +40,11 @@
 #include "cipher.h"
 #include "kex.h"
 #include "log.h"
+#include "digest.h"
 
 void
 kex_ecdh_hash(
-    const EVP_MD *evp_md,
+    int hash_alg,
     const EC_GROUP *ec_group,
     char *client_version_string,
     char *server_version_string,
@@ -56,8 +57,7 @@ kex_ecdh_hash(
     u_char **hash, u_int *hashlen)
 {
 	Buffer b;
-	EVP_MD_CTX md;
-	static u_char digest[EVP_MAX_MD_SIZE];
+	static u_char digest[SSH_DIGEST_MAX_LENGTH];
 
 	buffer_init(&b);
 	buffer_put_cstring(&b, client_version_string);
@@ -79,16 +79,14 @@ kex_ecdh_hash(
 #ifdef DEBUG_KEX
 	buffer_dump(&b);
 #endif
-	EVP_DigestInit(&md, evp_md);
-	EVP_DigestUpdate(&md, buffer_ptr(&b), buffer_len(&b));
-	EVP_DigestFinal(&md, digest, NULL);
+	if (ssh_digest_buffer(hash_alg, &b, digest, sizeof(digest)) != 0)
+		fatal("%s: ssh_digest_buffer failed", __func__);
 
 	buffer_free(&b);
 
 #ifdef DEBUG_KEX
-	dump_digest("hash", digest, EVP_MD_size(evp_md));
+	dump_digest("hash", digest, ssh_digest_bytes(hash_alg));
 #endif
 	*hash = digest;
-	*hashlen = EVP_MD_size(evp_md);
+	*hashlen = ssh_digest_bytes(hash_alg);
 }
-
diff --git a/usr.bin/ssh/kexecdhc.c b/usr.bin/ssh/kexecdhc.c
index 977b9aa1537..a7b0b879fbe 100644
--- a/usr.bin/ssh/kexecdhc.c
+++ b/usr.bin/ssh/kexecdhc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexecdhc.c,v 1.4 2013/05/17 00:13:13 djm Exp $ */
+/* $OpenBSD: kexecdhc.c,v 1.5 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  * Copyright (c) 2010 Damien Miller.  All rights reserved.
@@ -120,7 +120,7 @@ kexecdh_client(Kex *kex)
 
 	/* calc and verify H */
 	kex_ecdh_hash(
-	    kex->evp_md,
+	    kex->hash_alg,
 	    group,
 	    kex->client_version_string,
 	    kex->server_version_string,
diff --git a/usr.bin/ssh/kexecdhs.c b/usr.bin/ssh/kexecdhs.c
index b16cce949b2..334276275fb 100644
--- a/usr.bin/ssh/kexecdhs.c
+++ b/usr.bin/ssh/kexecdhs.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexecdhs.c,v 1.7 2013/11/02 22:24:24 markus Exp $ */
+/* $OpenBSD: kexecdhs.c,v 1.8 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  * Copyright (c) 2010 Damien Miller.  All rights reserved.
@@ -105,7 +105,7 @@ kexecdh_server(Kex *kex)
 	/* calc H */
 	key_to_blob(server_host_public, &server_host_key_blob, &sbloblen);
 	kex_ecdh_hash(
-	    kex->evp_md,
+	    kex->hash_alg,
 	    group,
 	    kex->client_version_string,
 	    kex->server_version_string,
diff --git a/usr.bin/ssh/kexgex.c b/usr.bin/ssh/kexgex.c
index 70206ef5c15..23ee598e91f 100644
--- a/usr.bin/ssh/kexgex.c
+++ b/usr.bin/ssh/kexgex.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexgex.c,v 1.27 2006/08/03 03:34:42 deraadt Exp $ */
+/* $OpenBSD: kexgex.c,v 1.28 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2000 Niels Provos.  All rights reserved.
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
@@ -34,10 +34,12 @@
 #include "cipher.h"
 #include "kex.h"
 #include "ssh2.h"
+#include "digest.h"
+#include "log.h"
 
 void
 kexgex_hash(
-    const EVP_MD *evp_md,
+    int hash_alg,
     char *client_version_string,
     char *server_version_string,
     char *ckexinit, int ckexinitlen,
@@ -50,8 +52,7 @@ kexgex_hash(
     u_char **hash, u_int *hashlen)
 {
 	Buffer b;
-	static u_char digest[EVP_MAX_MD_SIZE];
-	EVP_MD_CTX md;
+	static u_char digest[SSH_DIGEST_MAX_LENGTH];
 
 	buffer_init(&b);
 	buffer_put_cstring(&b, client_version_string);
@@ -82,15 +83,14 @@ kexgex_hash(
 #ifdef DEBUG_KEXDH
 	buffer_dump(&b);
 #endif
-
-	EVP_DigestInit(&md, evp_md);
-	EVP_DigestUpdate(&md, buffer_ptr(&b), buffer_len(&b));
-	EVP_DigestFinal(&md, digest, NULL);
+	if (ssh_digest_buffer(hash_alg, &b, digest, sizeof(digest)) != 0)
+		fatal("%s: ssh_digest_buffer failed", __func__);
 
 	buffer_free(&b);
-	*hash = digest;
-	*hashlen = EVP_MD_size(evp_md);
-#ifdef DEBUG_KEXDH
-	dump_digest("hash", digest, *hashlen);
+
+#ifdef DEBUG_KEX
+	dump_digest("hash", digest, ssh_digest_bytes(hash_alg));
 #endif
+	*hash = digest;
+	*hashlen = ssh_digest_bytes(hash_alg);
 }
diff --git a/usr.bin/ssh/kexgexc.c b/usr.bin/ssh/kexgexc.c
index b988d30e54c..160b655eef0 100644
--- a/usr.bin/ssh/kexgexc.c
+++ b/usr.bin/ssh/kexgexc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexgexc.c,v 1.13 2013/05/17 00:13:13 djm Exp $ */
+/* $OpenBSD: kexgexc.c,v 1.14 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2000 Niels Provos.  All rights reserved.
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
@@ -167,7 +167,7 @@ kexgex_client(Kex *kex)
 
 	/* calc and verify H */
 	kexgex_hash(
-	    kex->evp_md,
+	    kex->hash_alg,
 	    kex->client_version_string,
 	    kex->server_version_string,
 	    buffer_ptr(&kex->my), buffer_len(&kex->my),
diff --git a/usr.bin/ssh/kexgexs.c b/usr.bin/ssh/kexgexs.c
index 1df2243c398..415d8c7398d 100644
--- a/usr.bin/ssh/kexgexs.c
+++ b/usr.bin/ssh/kexgexs.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexgexs.c,v 1.16 2013/07/19 07:37:48 markus Exp $ */
+/* $OpenBSD: kexgexs.c,v 1.17 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2000 Niels Provos.  All rights reserved.
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
@@ -157,7 +157,7 @@ kexgex_server(Kex *kex)
 
 	/* calc H */
 	kexgex_hash(
-	    kex->evp_md,
+	    kex->hash_alg,
 	    kex->client_version_string,
 	    kex->server_version_string,
 	    buffer_ptr(&kex->peer), buffer_len(&kex->peer),
diff --git a/usr.bin/ssh/key.c b/usr.bin/ssh/key.c
index 17384d1a0b6..5b075ebe181 100644
--- a/usr.bin/ssh/key.c
+++ b/usr.bin/ssh/key.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: key.c,v 1.114 2013/12/29 04:20:04 djm Exp $ */
+/* $OpenBSD: key.c,v 1.115 2014/01/09 23:20:00 djm Exp $ */
 /*
  * read_bignum():
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -51,6 +51,7 @@
 #include "log.h"
 #include "misc.h"
 #include "ssh2.h"
+#include "digest.h"
 
 static int to_blob(const Key *, u_char **, u_int *, int);
 static Key *key_from_blob2(const u_char *, u_int, int);
@@ -345,28 +346,26 @@ u_char*
 key_fingerprint_raw(const Key *k, enum fp_type dgst_type,
     u_int *dgst_raw_length)
 {
-	const EVP_MD *md = NULL;
-	EVP_MD_CTX ctx;
 	u_char *blob = NULL;
 	u_char *retval = NULL;
 	u_int len = 0;
-	int nlen, elen;
+	int nlen, elen, hash_alg = -1;
 
 	*dgst_raw_length = 0;
 
+	/* XXX switch to DIGEST_* directly? */
 	switch (dgst_type) {
 	case SSH_FP_MD5:
-		md = EVP_md5();
+		hash_alg = SSH_DIGEST_MD5;
 		break;
 	case SSH_FP_SHA1:
-		md = EVP_sha1();
+		hash_alg = SSH_DIGEST_SHA1;
 		break;
 	case SSH_FP_SHA256:
-		md = EVP_sha256();
+		hash_alg = SSH_DIGEST_SHA256;
 		break;
 	default:
-		fatal("key_fingerprint_raw: bad digest type %d",
-		    dgst_type);
+		fatal("%s: bad digest type %d", __func__, dgst_type);
 	}
 	switch (k->type) {
 	case KEY_RSA1:
@@ -395,18 +394,19 @@ key_fingerprint_raw(const Key *k, enum fp_type dgst_type,
 	case KEY_UNSPEC:
 		return retval;
 	default:
-		fatal("key_fingerprint_raw: bad key type %d", k->type);
+		fatal("%s: bad key type %d", __func__, k->type);
 		break;
 	}
 	if (blob != NULL) {
-		retval = xmalloc(EVP_MAX_MD_SIZE);
-		EVP_DigestInit(&ctx, md);
-		EVP_DigestUpdate(&ctx, blob, len);
-		EVP_DigestFinal(&ctx, retval, dgst_raw_length);
+		retval = xmalloc(SSH_DIGEST_MAX_LENGTH);
+		if ((ssh_digest_memory(hash_alg, blob, len,
+		    retval, SSH_DIGEST_MAX_LENGTH)) != 0)
+			fatal("%s: digest_memory failed", __func__);
 		memset(blob, 0, len);
 		free(blob);
+		*dgst_raw_length = ssh_digest_bytes(hash_alg);
 	} else {
-		fatal("key_fingerprint_raw: blob is null");
+		fatal("%s: blob is null", __func__);
 	}
 	return retval;
 }
@@ -2132,8 +2132,8 @@ key_curve_nid_to_name(int nid)
 	return NULL;
 }
 
-const EVP_MD *
-key_ec_nid_to_evpmd(int nid)
+int
+key_ec_nid_to_hash_alg(int nid)
 {
 	int kbits = key_curve_nid_to_bits(nid);
 
@@ -2141,11 +2141,11 @@ key_ec_nid_to_evpmd(int nid)
 		fatal("%s: invalid nid %d", __func__, nid);
 	/* RFC5656 section 6.2.1 */
 	if (kbits <= 256)
-		return EVP_sha256();
+		return SSH_DIGEST_SHA256;
 	else if (kbits <= 384)
-		return EVP_sha384();
+		return SSH_DIGEST_SHA384;
 	else
-		return EVP_sha512();
+		return SSH_DIGEST_SHA512;
 }
 
 int
diff --git a/usr.bin/ssh/key.h b/usr.bin/ssh/key.h
index 6a6ea6aa334..99300425ad1 100644
--- a/usr.bin/ssh/key.h
+++ b/usr.bin/ssh/key.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: key.h,v 1.40 2013/12/06 13:39:49 markus Exp $ */
+/* $OpenBSD: key.h,v 1.41 2014/01/09 23:20:00 djm Exp $ */
 
 /*
  * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
@@ -124,7 +124,7 @@ const char	*key_curve_nid_to_name(int);
 u_int		 key_curve_nid_to_bits(int);
 int		 key_ecdsa_bits_to_nid(int);
 int		 key_ecdsa_key_to_nid(EC_KEY *);
-const EVP_MD	*key_ec_nid_to_evpmd(int nid);
+int		 key_ec_nid_to_hash_alg(int nid);
 int		 key_ec_validate_public(const EC_GROUP *, const EC_POINT *);
 int		 key_ec_validate_private(const EC_KEY *);
 char		*key_alg_list(int, int);
diff --git a/usr.bin/ssh/lib/Makefile b/usr.bin/ssh/lib/Makefile
index 67ef309ebc2..362606ebcfb 100644
--- a/usr.bin/ssh/lib/Makefile
+++ b/usr.bin/ssh/lib/Makefile
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile,v 1.70 2013/12/06 13:39:49 markus Exp $
+#	$OpenBSD: Makefile,v 1.71 2014/01/09 23:20:01 djm Exp $
 
 .PATH:		${.CURDIR}/..
 .include "${.CURDIR}/../Makefile.inc"
@@ -14,7 +14,7 @@ SRCS=	authfd.c authfile.c bufaux.c bufec.c bufbn.c buffer.c canohost.c \
 	kexdhc.c kexgexc.c kexecdhc.c msg.c progressmeter.c dns.c \
 	monitor_fdpass.c umac.c addrmatch.c schnorr.c jpake.c ssh-pkcs11.c \
 	krl.c smult_curve25519_ref.c kexc25519.c kexc25519c.c \
-	chacha.c poly1305.c cipher-chachapoly.c ssh-ed25519.c
+	chacha.c poly1305.c cipher-chachapoly.c ssh-ed25519.c digest.c
 
 # ed25519, from supercop
 SRCS+=	sc25519.c ge25519.c fe25519.c ed25519.c verify.c hash.c blocks.c
diff --git a/usr.bin/ssh/roaming_client.c b/usr.bin/ssh/roaming_client.c
index 32fdd51f206..50b9d764ee4 100644
--- a/usr.bin/ssh/roaming_client.c
+++ b/usr.bin/ssh/roaming_client.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: roaming_client.c,v 1.6 2013/10/16 02:31:46 djm Exp $ */
+/* $OpenBSD: roaming_client.c,v 1.7 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2004-2009 AppGate Network Security AB
  *
@@ -44,6 +44,7 @@
 #include "roaming.h"
 #include "ssh2.h"
 #include "sshconnect.h"
+#include "digest.h"
 
 /* import */
 extern Options options;
@@ -86,10 +87,8 @@ request_roaming(void)
 static void
 roaming_auth_required(void)
 {
-	u_char digest[SHA_DIGEST_LENGTH];
-	EVP_MD_CTX md;
+	u_char digest[SSH_DIGEST_MAX_LENGTH];
 	Buffer b;
-	const EVP_MD *evp_md = EVP_sha1();
 	u_int64_t chall, oldchall;
 
 	chall = packet_get_int64();
@@ -103,14 +102,13 @@ roaming_auth_required(void)
 	buffer_init(&b);
 	buffer_put_int64(&b, cookie);
 	buffer_put_int64(&b, chall);
-	EVP_DigestInit(&md, evp_md);
-	EVP_DigestUpdate(&md, buffer_ptr(&b), buffer_len(&b));
-	EVP_DigestFinal(&md, digest, NULL);
+	if (ssh_digest_buffer(SSH_DIGEST_SHA1, &b, digest, sizeof(digest)) != 0)
+		fatal("%s: ssh_digest_buffer failed", __func__);
 	buffer_free(&b);
 
 	packet_start(SSH2_MSG_KEX_ROAMING_AUTH);
 	packet_put_int64(key1 ^ get_recv_bytes());
-	packet_put_raw(digest, sizeof(digest));
+	packet_put_raw(digest, ssh_digest_bytes(SSH_DIGEST_SHA1));
 	packet_send();
 
 	oldkey1 = key1;
diff --git a/usr.bin/ssh/roaming_common.c b/usr.bin/ssh/roaming_common.c
index a5c7a9473ec..660a69e8a48 100644
--- a/usr.bin/ssh/roaming_common.c
+++ b/usr.bin/ssh/roaming_common.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: roaming_common.c,v 1.11 2013/11/03 10:37:19 djm Exp $ */
+/* $OpenBSD: roaming_common.c,v 1.12 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2004-2009 AppGate Network Security AB
  *
@@ -32,6 +32,7 @@
 #include "cipher.h"
 #include "buffer.h"
 #include "roaming.h"
+#include "digest.h"
 
 static size_t out_buf_size = 0;
 static char *out_buf = NULL;
@@ -221,9 +222,7 @@ resend_bytes(int fd, u_int64_t *offset)
 void
 calculate_new_key(u_int64_t *key, u_int64_t cookie, u_int64_t challenge)
 {
-	const EVP_MD *md = EVP_sha1();
-	EVP_MD_CTX ctx;
-	u_char hash[EVP_MAX_MD_SIZE];
+	u_char hash[SSH_DIGEST_MAX_LENGTH];
 	Buffer b;
 
 	buffer_init(&b);
@@ -231,12 +230,11 @@ calculate_new_key(u_int64_t *key, u_int64_t cookie, u_int64_t challenge)
 	buffer_put_int64(&b, cookie);
 	buffer_put_int64(&b, challenge);
 
-	EVP_DigestInit(&ctx, md);
-	EVP_DigestUpdate(&ctx, buffer_ptr(&b), buffer_len(&b));
-	EVP_DigestFinal(&ctx, hash, NULL);
+	if (ssh_digest_buffer(SSH_DIGEST_SHA1, &b, hash, sizeof(hash)) != 0)
+		fatal("%s: digest_buffer failed", __func__);
 
 	buffer_clear(&b);
-	buffer_append(&b, hash, EVP_MD_size(md));
+	buffer_append(&b, hash, ssh_digest_bytes(SSH_DIGEST_SHA1));
 	*key = buffer_get_int64(&b);
 	buffer_free(&b);
 }
diff --git a/usr.bin/ssh/schnorr.c b/usr.bin/ssh/schnorr.c
index 8088a1b5921..0e20e1b0159 100644
--- a/usr.bin/ssh/schnorr.c
+++ b/usr.bin/ssh/schnorr.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: schnorr.c,v 1.8 2013/11/08 00:39:15 djm Exp $ */
+/* $OpenBSD: schnorr.c,v 1.9 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2008 Damien Miller.  All rights reserved.
  *
@@ -39,6 +39,7 @@
 #include "log.h"
 
 #include "schnorr.h"
+#include "digest.h"
 
 /* #define SCHNORR_DEBUG */		/* Privacy-violating debugging */
 /* #define SCHNORR_MAIN */		/* Include main() selftest */
@@ -53,12 +54,12 @@
 
 /*
  * Calculate hash component of Schnorr signature H(g || g^v || g^x || id)
- * using the hash function defined by "evp_md". Returns signature as
+ * using the hash function defined by "hash_alg". Returns signature as
  * bignum or NULL on error.
  */
 static BIGNUM *
 schnorr_hash(const BIGNUM *p, const BIGNUM *q, const BIGNUM *g,
-    const EVP_MD *evp_md, const BIGNUM *g_v, const BIGNUM *g_x,
+    int hash_alg, const BIGNUM *g_v, const BIGNUM *g_x,
     const u_char *id, u_int idlen)
 {
 	u_char *digest;
@@ -84,7 +85,7 @@ schnorr_hash(const BIGNUM *p, const BIGNUM *q, const BIGNUM *g,
 
 	SCHNORR_DEBUG_BUF((buffer_ptr(&b), buffer_len(&b),
 	    "%s: hashblob", __func__));
-	if (hash_buffer(buffer_ptr(&b), buffer_len(&b), evp_md,
+	if (hash_buffer(buffer_ptr(&b), buffer_len(&b), hash_alg,
 	    &digest, &digest_len) != 0) {
 		error("%s: hash_buffer", __func__);
 		goto out;
@@ -109,7 +110,7 @@ schnorr_hash(const BIGNUM *p, const BIGNUM *q, const BIGNUM *g,
 /*
  * Generate Schnorr signature to prove knowledge of private value 'x' used
  * in public exponent g^x, under group defined by 'grp_p', 'grp_q' and 'grp_g'
- * using the hash function "evp_md".
+ * using the hash function "hash_alg".
  * 'idlen' bytes from 'id' will be included in the signature hash as an anti-
  * replay salt.
  * 
@@ -119,7 +120,7 @@ schnorr_hash(const BIGNUM *p, const BIGNUM *q, const BIGNUM *g,
  */
 int
 schnorr_sign(const BIGNUM *grp_p, const BIGNUM *grp_q, const BIGNUM *grp_g,
-    const EVP_MD *evp_md, const BIGNUM *x, const BIGNUM *g_x,
+    int hash_alg, const BIGNUM *x, const BIGNUM *g_x,
     const u_char *id, u_int idlen, BIGNUM **r_p, BIGNUM **e_p)
 {
 	int success = -1;
@@ -169,7 +170,7 @@ schnorr_sign(const BIGNUM *grp_p, const BIGNUM *grp_q, const BIGNUM *grp_g,
 	SCHNORR_DEBUG_BN((g_v, "%s: g_v = ", __func__));
 
 	/* h = H(g || g^v || g^x || id) */
-	if ((h = schnorr_hash(grp_p, grp_q, grp_g, evp_md, g_v, g_x,
+	if ((h = schnorr_hash(grp_p, grp_q, grp_g, hash_alg, g_v, g_x,
 	    id, idlen)) == NULL) {
 		error("%s: schnorr_hash failed", __func__);
 		goto out;
@@ -219,7 +220,7 @@ schnorr_sign_buf(const BIGNUM *grp_p, const BIGNUM *grp_q, const BIGNUM *grp_g,
 	Buffer b;
 	BIGNUM *r, *e;
 
-	if (schnorr_sign(grp_p, grp_q, grp_g, EVP_sha256(),
+	if (schnorr_sign(grp_p, grp_q, grp_g, SSH_DIGEST_SHA256,
 	    x, g_x, id, idlen, &r, &e) != 0)
 		return -1;
 
@@ -244,13 +245,13 @@ schnorr_sign_buf(const BIGNUM *grp_p, const BIGNUM *grp_q, const BIGNUM *grp_g,
 /*
  * Verify Schnorr signature { r (v - xh mod q), e (g^v mod p) } against
  * public exponent g_x (g^x) under group defined by 'grp_p', 'grp_q' and
- * 'grp_g' using hash "evp_md".
+ * 'grp_g' using hash "hash_alg".
  * Signature hash will be salted with 'idlen' bytes from 'id'.
  * Returns -1 on failure, 0 on incorrect signature or 1 on matching signature.
  */
 int
 schnorr_verify(const BIGNUM *grp_p, const BIGNUM *grp_q, const BIGNUM *grp_g,
-    const EVP_MD *evp_md, const BIGNUM *g_x, const u_char *id, u_int idlen,
+    int hash_alg, const BIGNUM *g_x, const u_char *id, u_int idlen,
     const BIGNUM *r, const BIGNUM *e)
 {
 	int success = -1;
@@ -298,7 +299,7 @@ schnorr_verify(const BIGNUM *grp_p, const BIGNUM *grp_q, const BIGNUM *grp_g,
 
 	SCHNORR_DEBUG_BN((g_xh, "%s: g_xh = ", __func__));
 	/* h = H(g || g^v || g^x || id) */
-	if ((h = schnorr_hash(grp_p, grp_q, grp_g, evp_md, e, g_x,
+	if ((h = schnorr_hash(grp_p, grp_q, grp_g, hash_alg, e, g_x,
 	    id, idlen)) == NULL) {
 		error("%s: schnorr_hash failed", __func__);
 		goto out;
@@ -381,7 +382,7 @@ schnorr_verify_buf(const BIGNUM *grp_p, const BIGNUM *grp_q,
 		goto out;
 	}
 
-	ret = schnorr_verify(grp_p, grp_q, grp_g, EVP_sha256(),
+	ret = schnorr_verify(grp_p, grp_q, grp_g, SSH_DIGEST_SHA256,
 	    g_x, id, idlen, r, e);
  out:
 	BN_clear_free(e);
@@ -439,43 +440,33 @@ bn_rand_range_gt_one(const BIGNUM *high)
 	return NULL;
 }
 
+/* XXX convert all callers of this to use ssh_digest_memory() directly */
 /*
  * Hash contents of buffer 'b' with hash 'md'. Returns 0 on success,
  * with digest via 'digestp' (caller to free) and length via 'lenp'.
  * Returns -1 on failure.
  */
 int
-hash_buffer(const u_char *buf, u_int len, const EVP_MD *md,
+hash_buffer(const u_char *buf, u_int len, int hash_alg,
     u_char **digestp, u_int *lenp)
 {
-	u_char digest[EVP_MAX_MD_SIZE];
-	u_int digest_len;
-	EVP_MD_CTX evp_md_ctx;
-	int success = -1;
+	u_char digest[SSH_DIGEST_MAX_LENGTH];
+	u_int digest_len = ssh_digest_bytes(hash_alg);
 
-	EVP_MD_CTX_init(&evp_md_ctx);
-
-	if (EVP_DigestInit_ex(&evp_md_ctx, md, NULL) != 1) {
-		error("%s: EVP_DigestInit_ex", __func__);
-		goto out;
-	}
-	if (EVP_DigestUpdate(&evp_md_ctx, buf, len) != 1) {
-		error("%s: EVP_DigestUpdate", __func__);
-		goto out;
+	if (digest_len == 0) {
+		error("%s: invalid hash", __func__);
+		return -1;
 	}
-	if (EVP_DigestFinal_ex(&evp_md_ctx, digest, &digest_len) != 1) {
-		error("%s: EVP_DigestFinal_ex", __func__);
-		goto out;
+	if (ssh_digest_memory(hash_alg, buf, len, digest, digest_len) != 0) {
+		error("%s: digest_memory failed", __func__);
+		return -1;
 	}
 	*digestp = xmalloc(digest_len);
 	*lenp = digest_len;
 	memcpy(*digestp, digest, *lenp);
-	success = 0;
- out:
-	EVP_MD_CTX_cleanup(&evp_md_ctx);
 	bzero(digest, sizeof(digest));
 	digest_len = 0;
-	return success;
+	return 0;
 }
 
 /* print formatted string followed by bignum */
diff --git a/usr.bin/ssh/schnorr.h b/usr.bin/ssh/schnorr.h
index 9730b47cef3..e2405c10290 100644
--- a/usr.bin/ssh/schnorr.h
+++ b/usr.bin/ssh/schnorr.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: schnorr.h,v 1.1 2009/03/05 07:18:19 djm Exp $ */
+/* $OpenBSD: schnorr.h,v 1.2 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2009 Damien Miller.  All rights reserved.
  *
@@ -27,7 +27,7 @@ struct modp_group {
 };
 
 BIGNUM *bn_rand_range_gt_one(const BIGNUM *high);
-int hash_buffer(const u_char *, u_int, const EVP_MD *, u_char **, u_int *);
+int hash_buffer(const u_char *, u_int, int, u_char **, u_int *);
 void debug3_bn(const BIGNUM *, const char *, ...)
     __attribute__((__nonnull__ (2)))
     __attribute__((format(printf, 2, 3)));
@@ -40,7 +40,7 @@ void modp_group_free(struct modp_group *);
 /* Signature and verification functions */
 int
 schnorr_sign(const BIGNUM *grp_p, const BIGNUM *grp_q, const BIGNUM *grp_g,
-    const EVP_MD *evp_md, const BIGNUM *x, const BIGNUM *g_x,
+    int hash_alg, const BIGNUM *x, const BIGNUM *g_x,
     const u_char *id, u_int idlen, BIGNUM **r_p, BIGNUM **e_p);
 int
 schnorr_sign_buf(const BIGNUM *grp_p, const BIGNUM *grp_q, const BIGNUM *grp_g,
@@ -48,7 +48,7 @@ schnorr_sign_buf(const BIGNUM *grp_p, const BIGNUM *grp_q, const BIGNUM *grp_g,
     u_char **sig, u_int *siglen);
 int
 schnorr_verify(const BIGNUM *grp_p, const BIGNUM *grp_q, const BIGNUM *grp_g,
-    const EVP_MD *evp_md, const BIGNUM *g_x, const u_char *id, u_int idlen,
+    int hash_alg, const BIGNUM *g_x, const u_char *id, u_int idlen,
     const BIGNUM *r, const BIGNUM *e);
 int
 schnorr_verify_buf(const BIGNUM *grp_p, const BIGNUM *grp_q,
diff --git a/usr.bin/ssh/ssh-dss.c b/usr.bin/ssh/ssh-dss.c
index 9b28af7f9e4..cd206fd44c3 100644
--- a/usr.bin/ssh/ssh-dss.c
+++ b/usr.bin/ssh/ssh-dss.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-dss.c,v 1.29 2013/12/27 22:30:17 djm Exp $ */
+/* $OpenBSD: ssh-dss.c,v 1.30 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  *
@@ -35,6 +35,7 @@
 #include "compat.h"
 #include "log.h"
 #include "key.h"
+#include "digest.h"
 
 #define INTBLOB_LEN	20
 #define SIGBLOB_LEN	(2*INTBLOB_LEN)
@@ -44,10 +45,8 @@ ssh_dss_sign(const Key *key, u_char **sigp, u_int *lenp,
     const u_char *data, u_int datalen)
 {
 	DSA_SIG *sig;
-	const EVP_MD *evp_md = EVP_sha1();
-	EVP_MD_CTX md;
-	u_char digest[EVP_MAX_MD_SIZE], sigblob[SIGBLOB_LEN];
-	u_int rlen, slen, len, dlen;
+	u_char digest[SSH_DIGEST_MAX_LENGTH], sigblob[SIGBLOB_LEN];
+	u_int rlen, slen, len, dlen = ssh_digest_bytes(SSH_DIGEST_SHA1);
 	Buffer b;
 
 	if (key == NULL || key_type_plain(key->type) != KEY_DSA ||
@@ -56,9 +55,11 @@ ssh_dss_sign(const Key *key, u_char **sigp, u_int *lenp,
 		return -1;
 	}
 
-	EVP_DigestInit(&md, evp_md);
-	EVP_DigestUpdate(&md, data, datalen);
-	EVP_DigestFinal(&md, digest, &dlen);
+	if (ssh_digest_memory(SSH_DIGEST_SHA1, data, datalen,
+	    digest, sizeof(digest)) != 0) {
+		error("%s: ssh_digest_memory failed", __func__);
+		return -1;
+	}
 
 	sig = DSA_do_sign(digest, dlen, key->dsa);
 	memset(digest, 'd', sizeof(digest));
@@ -108,10 +109,8 @@ ssh_dss_verify(const Key *key, const u_char *signature, u_int signaturelen,
     const u_char *data, u_int datalen)
 {
 	DSA_SIG *sig;
-	const EVP_MD *evp_md = EVP_sha1();
-	EVP_MD_CTX md;
-	u_char digest[EVP_MAX_MD_SIZE], *sigblob;
-	u_int len, dlen;
+	u_char digest[SSH_DIGEST_MAX_LENGTH], *sigblob;
+	u_int len, dlen = ssh_digest_bytes(SSH_DIGEST_SHA1);
 	int rlen, ret;
 	Buffer b;
 
@@ -170,9 +169,11 @@ ssh_dss_verify(const Key *key, const u_char *signature, u_int signaturelen,
 	free(sigblob);
 
 	/* sha1 the data */
-	EVP_DigestInit(&md, evp_md);
-	EVP_DigestUpdate(&md, data, datalen);
-	EVP_DigestFinal(&md, digest, &dlen);
+	if (ssh_digest_memory(SSH_DIGEST_SHA1, data, datalen,
+	    digest, sizeof(digest)) != 0) {
+		error("%s: digest_memory failed", __func__);
+		return -1;
+	}
 
 	ret = DSA_do_verify(digest, dlen, sig, key->dsa);
 	memset(digest, 'd', sizeof(digest));
diff --git a/usr.bin/ssh/ssh-ecdsa.c b/usr.bin/ssh/ssh-ecdsa.c
index acd14d7cbf8..4570aa3d355 100644
--- a/usr.bin/ssh/ssh-ecdsa.c
+++ b/usr.bin/ssh/ssh-ecdsa.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-ecdsa.c,v 1.7 2013/12/27 22:30:17 djm Exp $ */
+/* $OpenBSD: ssh-ecdsa.c,v 1.8 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  * Copyright (c) 2010 Damien Miller.  All rights reserved.
@@ -38,15 +38,15 @@
 #include "compat.h"
 #include "log.h"
 #include "key.h"
+#include "digest.h"
 
 int
 ssh_ecdsa_sign(const Key *key, u_char **sigp, u_int *lenp,
     const u_char *data, u_int datalen)
 {
 	ECDSA_SIG *sig;
-	const EVP_MD *evp_md;
-	EVP_MD_CTX md;
-	u_char digest[EVP_MAX_MD_SIZE];
+	int hash_alg;
+	u_char digest[SSH_DIGEST_MAX_LENGTH];
 	u_int len, dlen;
 	Buffer b, bb;
 
@@ -56,10 +56,16 @@ ssh_ecdsa_sign(const Key *key, u_char **sigp, u_int *lenp,
 		return -1;
 	}
 
-	evp_md = key_ec_nid_to_evpmd(key->ecdsa_nid);
-	EVP_DigestInit(&md, evp_md);
-	EVP_DigestUpdate(&md, data, datalen);
-	EVP_DigestFinal(&md, digest, &dlen);
+	hash_alg = key_ec_nid_to_hash_alg(key->ecdsa_nid);
+	if ((dlen = ssh_digest_bytes(hash_alg)) == 0) {
+		error("%s: bad hash algorithm %d", __func__, hash_alg);
+		return -1;
+	}
+	if (ssh_digest_memory(hash_alg, data, datalen,
+	    digest, sizeof(digest)) != 0) {
+		error("%s: digest_memory failed", __func__);
+		return -1;
+	}
 
 	sig = ECDSA_do_sign(digest, dlen, key->ecdsa);
 	memset(digest, 'd', sizeof(digest));
@@ -94,9 +100,8 @@ ssh_ecdsa_verify(const Key *key, const u_char *signature, u_int signaturelen,
     const u_char *data, u_int datalen)
 {
 	ECDSA_SIG *sig;
-	const EVP_MD *evp_md;
-	EVP_MD_CTX md;
-	u_char digest[EVP_MAX_MD_SIZE], *sigblob;
+	int hash_alg;
+	u_char digest[SSH_DIGEST_MAX_LENGTH], *sigblob;
 	u_int len, dlen;
 	int rlen, ret;
 	Buffer b, bb;
@@ -108,8 +113,6 @@ ssh_ecdsa_verify(const Key *key, const u_char *signature, u_int signaturelen,
 		return -1;
 	}
 
-	evp_md = key_ec_nid_to_evpmd(key->ecdsa_nid);
-
 	/* fetch signature */
 	buffer_init(&b);
 	buffer_append(&b, signature, signaturelen);
@@ -150,9 +153,16 @@ ssh_ecdsa_verify(const Key *key, const u_char *signature, u_int signaturelen,
 	free(sigblob);
 
 	/* hash the data */
-	EVP_DigestInit(&md, evp_md);
-	EVP_DigestUpdate(&md, data, datalen);
-	EVP_DigestFinal(&md, digest, &dlen);
+	hash_alg = key_ec_nid_to_hash_alg(key->ecdsa_nid);
+	if ((dlen = ssh_digest_bytes(hash_alg)) == 0) {
+		error("%s: bad hash algorithm %d", __func__, hash_alg);
+		return -1;
+	}
+	if (ssh_digest_memory(hash_alg, data, datalen,
+	    digest, sizeof(digest)) != 0) {
+		error("%s: digest_memory failed", __func__);
+		return -1;
+	}
 
 	ret = ECDSA_do_verify(digest, dlen, sig, key->ecdsa);
 	memset(digest, 'd', sizeof(digest));
diff --git a/usr.bin/ssh/ssh-rsa.c b/usr.bin/ssh/ssh-rsa.c
index c2ed72cc36f..27b50808593 100644
--- a/usr.bin/ssh/ssh-rsa.c
+++ b/usr.bin/ssh/ssh-rsa.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-rsa.c,v 1.49 2013/12/30 23:52:27 djm Exp $ */
+/* $OpenBSD: ssh-rsa.c,v 1.50 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2000, 2003 Markus Friedl <markus@openbsd.org>
  *
@@ -29,6 +29,7 @@
 #include "compat.h"
 #include "misc.h"
 #include "ssh.h"
+#include "digest.h"
 
 static int openssh_RSA_verify(int, u_char *, u_int, u_char *, u_int, RSA *);
 
@@ -37,9 +38,8 @@ int
 ssh_rsa_sign(const Key *key, u_char **sigp, u_int *lenp,
     const u_char *data, u_int datalen)
 {
-	const EVP_MD *evp_md;
-	EVP_MD_CTX md;
-	u_char digest[EVP_MAX_MD_SIZE], *sig;
+	int hash_alg;
+	u_char digest[SSH_DIGEST_MAX_LENGTH], *sig;
 	u_int slen, dlen, len;
 	int ok, nid;
 	Buffer b;
@@ -50,14 +50,18 @@ ssh_rsa_sign(const Key *key, u_char **sigp, u_int *lenp,
 		return -1;
 	}
 
+	/* hash the data */
+	hash_alg = SSH_DIGEST_SHA1;
 	nid = NID_sha1;
-	if ((evp_md = EVP_get_digestbynid(nid)) == NULL) {
-		error("%s: EVP_get_digestbynid %d failed", __func__, nid);
+	if ((dlen = ssh_digest_bytes(hash_alg)) == 0) {
+		error("%s: bad hash algorithm %d", __func__, hash_alg);
+		return -1;
+	}
+	if (ssh_digest_memory(hash_alg, data, datalen,
+	    digest, sizeof(digest)) != 0) {
+		error("%s: ssh_digest_memory failed", __func__);
 		return -1;
 	}
-	EVP_DigestInit(&md, evp_md);
-	EVP_DigestUpdate(&md, data, datalen);
-	EVP_DigestFinal(&md, digest, &dlen);
 
 	slen = RSA_size(key->rsa);
 	sig = xmalloc(slen);
@@ -106,12 +110,11 @@ ssh_rsa_verify(const Key *key, const u_char *signature, u_int signaturelen,
     const u_char *data, u_int datalen)
 {
 	Buffer b;
-	const EVP_MD *evp_md;
-	EVP_MD_CTX md;
+	int hash_alg;
 	char *ktype;
-	u_char digest[EVP_MAX_MD_SIZE], *sigblob;
+	u_char digest[SSH_DIGEST_MAX_LENGTH], *sigblob;
 	u_int len, dlen, modlen;
-	int rlen, ret, nid;
+	int rlen, ret;
 
 	if (key == NULL || key_type_plain(key->type) != KEY_RSA ||
 	    key->rsa == NULL) {
@@ -158,17 +161,20 @@ ssh_rsa_verify(const Key *key, const u_char *signature, u_int signaturelen,
 		memset(sigblob, 0, diff);
 		len = modlen;
 	}
-	nid = NID_sha1;
-	if ((evp_md = EVP_get_digestbynid(nid)) == NULL) {
-		error("%s: EVP_get_digestbynid %d failed", __func__, nid);
-		free(sigblob);
+	/* hash the data */
+	hash_alg = SSH_DIGEST_SHA1;
+	if ((dlen = ssh_digest_bytes(hash_alg)) == 0) {
+		error("%s: bad hash algorithm %d", __func__, hash_alg);
+		return -1;
+	}
+	if (ssh_digest_memory(hash_alg, data, datalen,
+	    digest, sizeof(digest)) != 0) {
+		error("%s: ssh_digest_memory failed", __func__);
 		return -1;
 	}
-	EVP_DigestInit(&md, evp_md);
-	EVP_DigestUpdate(&md, data, datalen);
-	EVP_DigestFinal(&md, digest, &dlen);
 
-	ret = openssh_RSA_verify(nid, digest, dlen, sigblob, len, key->rsa);
+	ret = openssh_RSA_verify(hash_alg, digest, dlen, sigblob, len,
+	    key->rsa);
 	memset(digest, 'd', sizeof(digest));
 	memset(sigblob, 's', len);
 	free(sigblob);
@@ -195,7 +201,7 @@ static const u_char id_sha1[] = {
 };
 
 static int
-openssh_RSA_verify(int type, u_char *hash, u_int hashlen,
+openssh_RSA_verify(int hash_alg, u_char *hash, u_int hashlen,
     u_char *sigbuf, u_int siglen, RSA *rsa)
 {
 	u_int ret, rsasize, oidlen = 0, hlen = 0;
@@ -204,8 +210,8 @@ openssh_RSA_verify(int type, u_char *hash, u_int hashlen,
 	u_char *decrypted = NULL;
 
 	ret = 0;
-	switch (type) {
-	case NID_sha1:
+	switch (hash_alg) {
+	case SSH_DIGEST_SHA1:
 		oid = id_sha1;
 		oidlen = sizeof(id_sha1);
 		hlen = 20;
diff --git a/usr.bin/ssh/sshconnect2.c b/usr.bin/ssh/sshconnect2.c
index a992668a0d9..846a730cf59 100644
--- a/usr.bin/ssh/sshconnect2.c
+++ b/usr.bin/ssh/sshconnect2.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshconnect2.c,v 1.200 2013/12/30 23:52:28 djm Exp $ */
+/* $OpenBSD: sshconnect2.c,v 1.201 2014/01/09 23:20:00 djm Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  * Copyright (c) 2008 Damien Miller.  All rights reserved.
@@ -1000,7 +1000,7 @@ jpake_password_to_secret(Authctxt *authctxt, const char *crypt_scheme,
 	debug3("%s: crypted = %s", __func__, crypted);
 #endif
 
-	if (hash_buffer(crypted, strlen(crypted), EVP_sha256(),
+	if (hash_buffer(crypted, strlen(crypted), SSH_DIGEST_SHA1,
 	    &secret, &secret_len) != 0)
 		fatal("%s: hash_buffer", __func__);