- djm@cvs.openbsd.org 2014/01/09 23:20:00

     [digest.c digest.h hostfile.c kex.c kex.h kexc25519.c kexc25519c.c]
     [kexc25519s.c kexdh.c kexecdh.c kexecdhc.c kexecdhs.c kexgex.c kexgexc.c]
     [kexgexs.c key.c key.h roaming_client.c roaming_common.c schnorr.c]
     [schnorr.h ssh-dss.c ssh-ecdsa.c ssh-rsa.c sshconnect2.c]
     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@

27 files changed, 458 insertions, 235 deletions

diff --git a/ChangeLog b/ChangeLog
index df1d5ea6a..a1d37bc25 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -9,6 +9,15 @@
      with the year, and rearrange a comparison to avoid a potentional signed
      arithmetic overflow that would give the wrong result.
      ok djm@
+   - djm@cvs.openbsd.org 2014/01/09 23:20:00
+     [digest.c digest.h hostfile.c kex.c kex.h kexc25519.c kexc25519c.c]
+     [kexc25519s.c kexdh.c kexecdh.c kexecdhc.c kexecdhs.c kexgex.c kexgexc.c]
+     [kexgexs.c key.c key.h roaming_client.c roaming_common.c schnorr.c]
+     [schnorr.h ssh-dss.c ssh-ecdsa.c ssh-rsa.c sshconnect2.c]
+     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@
 
 20140108
  - (djm) [regress/.cvsignore] Ignore regress test droppings; ok dtucker@
diff --git a/Makefile.in b/Makefile.in
index e789b476a..4a930c665 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -1,4 +1,4 @@
-# $Id: Makefile.in,v 1.348 2013/12/08 04:53:28 djm Exp $
+# $Id: Makefile.in,v 1.349 2014/01/09 23:58:53 djm Exp $
 
 # uncomment if you run a non bourne compatable shell. Ie. csh
 #SHELL = @SH@
@@ -75,7 +75,7 @@ LIBSSH_OBJS=authfd.o authfile.o bufaux.o bufbn.o buffer.o \
         msg.o progressmeter.o dns.o entropy.o gss-genr.o umac.o umac128.o \
         jpake.o schnorr.o ssh-pkcs11.o krl.o smult_curve25519_ref.o \
         kexc25519.o kexc25519c.o poly1305.o chacha.o cipher-chachapoly.o \
-        ssh-ed25519.o \
+        ssh-ed25519.o digest.o \
         sc25519.o ge25519.o fe25519.o ed25519.o verify.o hash.o blocks.o \
 
 SSHOBJS= ssh.o readconf.o clientloop.o sshtty.o \
diff --git a/digest.c b/digest.c
new file mode 100644
index 000000000..59a8ffe0d
--- /dev/null
+++ b/digest.c
@@ -0,0 +1,148 @@
+/* $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 "includes.h"
+
+#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 },
+#ifdef HAVE_EVP_SHA256 /* XXX replace with local if missing */
+        { SSH_DIGEST_SHA256,    "SHA256",       32,     EVP_sha256 },
+        { SSH_DIGEST_SHA384,    "SHA384",       48,     EVP_sha384 },
+        { SSH_DIGEST_SHA512,    "SHA512",       64,     EVP_sha512 },
+#endif
+        { -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/digest.h b/digest.h
new file mode 100644
index 000000000..faefda3f5
--- /dev/null
+++ b/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/hostfile.c b/hostfile.c
index 2ff4c48b4..2778fb5df 100644
--- a/hostfile.c
+++ b/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
@@ -57,6 +57,7 @@
 #include "hostfile.h"
 #include "log.h"
 #include "misc.h"
+#include "digest.h"
 
 struct hostkeys {
         struct hostkey_entry *entries;
diff --git a/kex.c b/kex.c
index b38bae0f0..dbb1a9816 100644
--- a/kex.c
+++ b/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.
  *
@@ -49,6 +49,7 @@
 #include "dispatch.h"
 #include "monitor.h"
 #include "roaming.h"
+#include "digest.h"
 
 #if OPENSSL_VERSION_NUMBER >= 0x00907000L
 # if defined(HAVE_EVP_SHA256)
@@ -66,26 +67,30 @@ 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_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 },
 #ifdef HAVE_EVP_SHA256
-        { KEX_DHGEX_SHA256, KEX_DH_GEX_SHA256, 0, EVP_sha256 },
+        { KEX_DHGEX_SHA256, KEX_DH_GEX_SHA256, 0, SSH_DIGEST_SHA256 },
 #endif
 #ifdef OPENSSL_HAS_ECC
-        { 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_NISTP256, KEX_ECDH_SHA2,
+            NID_X9_62_prime256v1, SSH_DIGEST_SHA256 },
+        { KEX_ECDH_SHA2_NISTP384, KEX_ECDH_SHA2, NID_secp384r1,
+            SSH_DIGEST_SHA384 },
 # ifdef OPENSSL_HAS_NISTP521
-        { KEX_ECDH_SHA2_NISTP521, KEX_ECDH_SHA2, NID_secp521r1, EVP_sha512 },
+        { KEX_ECDH_SHA2_NISTP521, KEX_ECDH_SHA2, NID_secp521r1,
+            SSH_DIGEST_SHA512 },
 # endif
 #endif
+        { KEX_DH1, KEX_DH_GRP1_SHA1, 0, SSH_DIGEST_SHA1 },
 #ifdef HAVE_EVP_SHA256
-        { KEX_CURVE25519_SHA256, KEX_C25519_SHA256, 0, EVP_sha256 },
+        { KEX_CURVE25519_SHA256, KEX_C25519_SHA256, 0, SSH_DIGEST_SHA256 },
 #endif
-        { NULL, -1, -1, NULL},
+        { NULL, -1, -1, -1},
 };
 
 char *
@@ -406,7 +411,7 @@ 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;
 }
 
@@ -532,27 +537,31 @@ 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:
@@ -560,12 +569,15 @@ 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
@@ -615,33 +627,33 @@ 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/kex.h b/kex.h
index 800a69233..fbe4940e8 100644
--- a/kex.h
+++ b/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.
@@ -133,7 +133,7 @@ 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;
@@ -170,17 +170,17 @@ 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 *);
 #ifdef OPENSSL_HAS_ECC
 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 *);
 #endif
 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/kexc25519.c b/kexc25519.c
index 348a7d50d..8dd363991 100644
--- a/kexc25519.c
+++ b/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.
@@ -41,6 +41,7 @@
 #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])
@@ -78,7 +79,7 @@ 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,
@@ -90,8 +91,7 @@ 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);
@@ -113,15 +113,14 @@ 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/kexc25519c.c b/kexc25519c.c
index f741566cc..4655c2542 100644
--- a/kexc25519c.c
+++ b/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.
@@ -97,7 +97,7 @@ 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/kexc25519s.c b/kexc25519s.c
index 784841b82..dc4f56c80 100644
--- a/kexc25519s.c
+++ b/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.
@@ -81,7 +81,7 @@ 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/kexdh.c b/kexdh.c
index 56e22f5bc..e7cdadc90 100644
--- a/kexdh.c
+++ b/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.
  *
@@ -36,6 +36,8 @@
 #include "key.h"
 #include "cipher.h"
 #include "kex.h"
+#include "digest.h"
+#include "log.h"
 
 void
 kex_dh_hash(
@@ -50,9 +52,7 @@ 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);
@@ -74,15 +74,14 @@ 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/kexecdh.c b/kexecdh.c
index c948fe20a..c52c5e234 100644
--- a/kexecdh.c
+++ b/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.
@@ -44,10 +44,11 @@
 #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,
@@ -60,8 +61,7 @@ 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);
@@ -83,17 +83,15 @@ 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);
 }
-
 #endif /* OPENSSL_HAS_ECC */
diff --git a/kexecdhc.c b/kexecdhc.c
index 6193836c7..fc62cec55 100644
--- a/kexecdhc.c
+++ b/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.
@@ -124,7 +124,7 @@ 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/kexecdhs.c b/kexecdhs.c
index 431fd2c2c..d1dd8c7fb 100644
--- a/kexecdhs.c
+++ b/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.
@@ -109,7 +109,7 @@ 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/kexgex.c b/kexgex.c
index b60ab5c53..c2e6bc16d 100644
--- a/kexgex.c
+++ b/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.
@@ -36,10 +36,12 @@
 #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,
@@ -52,8 +54,7 @@ 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);
@@ -84,15 +85,14 @@ 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/kexgexc.c b/kexgexc.c
index 5a3be2005..ca771edfe 100644
--- a/kexgexc.c
+++ b/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.
@@ -170,7 +170,7 @@ 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/kexgexs.c b/kexgexs.c
index 4e473fc73..90853403e 100644
--- a/kexgexs.c
+++ b/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.
@@ -160,7 +160,7 @@ 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/key.c b/key.c
index b0bb46f3d..914233808 100644
--- a/key.c
+++ b/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
@@ -56,6 +56,7 @@
 #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);
@@ -358,30 +359,26 @@ 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;
-#ifdef HAVE_EVP_SHA256
         case SSH_FP_SHA256:
-                md = EVP_sha256();
+                hash_alg = SSH_DIGEST_SHA256;
                 break;
-#endif
         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:
@@ -410,18 +407,19 @@ 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;
 }
@@ -2211,8 +2209,8 @@ key_curve_nid_to_name(int nid)
 }
 
 #ifdef OPENSSL_HAS_ECC
-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);
 
@@ -2220,11 +2218,11 @@ 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/key.h b/key.h
index 6a049d277..d8ad13d08 100644
--- a/key.h
+++ b/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.
@@ -131,7 +131,7 @@ u_int		 key_curve_nid_to_bits(int);
 int              key_ecdsa_bits_to_nid(int);
 #ifdef OPENSSL_HAS_ECC
 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 *);
 #endif
diff --git a/roaming_client.c b/roaming_client.c
index 2fb623121..de049cdc1 100644
--- a/roaming_client.c
+++ b/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
  *
@@ -48,6 +48,7 @@
 #include "roaming.h"
 #include "ssh2.h"
 #include "sshconnect.h"
+#include "digest.h"
 
 /* import */
 extern Options options;
@@ -90,10 +91,8 @@ 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();
@@ -107,14 +106,13 @@ 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/roaming_common.c b/roaming_common.c
index 86b3372ef..787bef04a 100644
--- a/roaming_common.c
+++ b/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
  *
@@ -36,6 +36,7 @@
 #include "cipher.h"
 #include "buffer.h"
 #include "roaming.h"
+#include "digest.h"
 
 static size_t out_buf_size = 0;
 static char *out_buf = NULL;
@@ -225,9 +226,7 @@ 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);
@@ -235,12 +234,11 @@ 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/schnorr.c b/schnorr.c
index 93822fed4..aa3a57770 100644
--- a/schnorr.c
+++ b/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.
  *
@@ -41,6 +41,7 @@
 #include "log.h"
 
 #include "schnorr.h"
+#include "digest.h"
 
 #include "openbsd-compat/openssl-compat.h"
 
@@ -57,12 +58,12 @@
 
 /*
  * 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;
@@ -88,7 +89,7 @@ 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;
@@ -113,7 +114,7 @@ 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.
  * 
@@ -123,7 +124,7 @@ 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;
@@ -173,7 +174,7 @@ 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;
@@ -223,7 +224,7 @@ 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;
 
@@ -248,13 +249,13 @@ 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;
@@ -302,7 +303,7 @@ 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;
@@ -385,7 +386,7 @@ 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);
@@ -443,43 +444,33 @@ 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/schnorr.h b/schnorr.h
index 9730b47ce..e2405c102 100644
--- a/schnorr.h
+++ b/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/ssh-dss.c b/ssh-dss.c
index a6292aa84..7b897475c 100644
--- a/ssh-dss.c
+++ b/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.
  *
@@ -38,6 +38,7 @@
 #include "compat.h"
 #include "log.h"
 #include "key.h"
+#include "digest.h"
 
 #define INTBLOB_LEN     20
 #define SIGBLOB_LEN     (2*INTBLOB_LEN)
@@ -47,10 +48,8 @@ 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 ||
@@ -59,9 +58,11 @@ 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));
@@ -111,10 +112,8 @@ 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;
 
@@ -173,9 +172,11 @@ 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/ssh-ecdsa.c b/ssh-ecdsa.c
index 52f9e74c0..10ad9da60 100644
--- a/ssh-ecdsa.c
+++ b/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.
@@ -42,15 +42,15 @@
 #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;
 
@@ -60,10 +60,16 @@ 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));
@@ -98,9 +104,8 @@ 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;
@@ -112,8 +117,6 @@ 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);
@@ -154,9 +157,16 @@ 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/ssh-rsa.c b/ssh-rsa.c
index b1ac50b31..a2112d033 100644
--- a/ssh-rsa.c
+++ b/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>
  *
@@ -32,6 +32,7 @@
 #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 *);
 
@@ -40,9 +41,8 @@ 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;
@@ -53,14 +53,18 @@ 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);
@@ -109,12 +113,11 @@ 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) {
@@ -161,17 +164,20 @@ 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);
@@ -198,7 +204,7 @@ 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;
@@ -207,8 +213,8 @@ 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/sshconnect2.c b/sshconnect2.c
index 0d339b9c5..8acffc5c3 100644
--- a/sshconnect2.c
+++ b/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.
@@ -1006,7 +1006,7 @@ 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__);