- djm@cvs.openbsd.org 2014/02/02 03:44:32

     [auth1.c auth2-chall.c auth2-passwd.c authfile.c bufaux.c bufbn.c]
     [buffer.c cipher-3des1.c cipher.c clientloop.c gss-serv.c kex.c]
     [kexdhc.c kexdhs.c kexecdhc.c kexgexc.c kexecdhs.c kexgexs.c key.c]
     [monitor.c monitor_wrap.c packet.c readpass.c rsa.c serverloop.c]
     [ssh-add.c ssh-agent.c ssh-dss.c ssh-ecdsa.c ssh-ed25519.c]
     [ssh-keygen.c ssh-rsa.c sshconnect.c sshconnect1.c sshconnect2.c]
     [sshd.c]
     convert memset of potentially-private data to explicit_bzero()

37 files changed, 168 insertions, 154 deletions

diff --git a/ChangeLog b/ChangeLog
index a3f75a8d2..d5ea77c1f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -44,6 +44,15 @@
      [openbsd-compat/explicit_bzero.c openbsd-compat/openbsd-compat.h]
      replace most bzero with explicit_bzero, except a few that cna be memset
      ok djm dtucker
+   - djm@cvs.openbsd.org 2014/02/02 03:44:32
+     [auth1.c auth2-chall.c auth2-passwd.c authfile.c bufaux.c bufbn.c]
+     [buffer.c cipher-3des1.c cipher.c clientloop.c gss-serv.c kex.c]
+     [kexdhc.c kexdhs.c kexecdhc.c kexgexc.c kexecdhs.c kexgexs.c key.c]
+     [monitor.c monitor_wrap.c packet.c readpass.c rsa.c serverloop.c]
+     [ssh-add.c ssh-agent.c ssh-dss.c ssh-ecdsa.c ssh-ed25519.c]
+     [ssh-keygen.c ssh-rsa.c sshconnect.c sshconnect1.c sshconnect2.c]
+     [sshd.c]
+     convert memset of potentially-private data to explicit_bzero()
 
 20140131
  - (djm) [sandbox-seccomp-filter.c sandbox-systrace.c] Allow shutdown(2)
diff --git a/auth1.c b/auth1.c
index f1ac59814..0f870b3b6 100644
--- a/auth1.c
+++ b/auth1.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: auth1.c,v 1.79 2013/05/19 02:42:42 djm Exp $ */
+/* $OpenBSD: auth1.c,v 1.80 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
  *                    All rights reserved
@@ -129,7 +129,7 @@ auth1_process_password(Authctxt *authctxt)
         /* Try authentication with the password. */
         authenticated = PRIVSEP(auth_password(authctxt, password));
 
-        memset(password, 0, dlen);
+        explicit_bzero(password, dlen);
         free(password);
 
         return (authenticated);
@@ -222,7 +222,7 @@ auth1_process_tis_response(Authctxt *authctxt)
         response = packet_get_string(&dlen);
         packet_check_eom();
         authenticated = verify_response(authctxt, response);
-        memset(response, 'r', dlen);
+        explicit_bzero(response, dlen);
         free(response);
 
         return (authenticated);
diff --git a/auth2-chall.c b/auth2-chall.c
index 4cfd8ff5b..980250a91 100644
--- a/auth2-chall.c
+++ b/auth2-chall.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: auth2-chall.c,v 1.40 2014/01/31 16:39:19 tedu Exp $ */
+/* $OpenBSD: auth2-chall.c,v 1.41 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  * Copyright (c) 2001 Per Allansson.  All rights reserved.
@@ -312,7 +312,7 @@ input_userauth_info_response(int type, u_int32_t seq, void *ctxt)
         res = kbdintctxt->device->respond(kbdintctxt->ctxt, nresp, response);
 
         for (i = 0; i < nresp; i++) {
-                memset(response[i], 'r', strlen(response[i]));
+                explicit_bzero(response[i], strlen(response[i]));
                 free(response[i]);
         }
         free(response);
diff --git a/auth2-passwd.c b/auth2-passwd.c
index 21bc5047d..707680cd0 100644
--- a/auth2-passwd.c
+++ b/auth2-passwd.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: auth2-passwd.c,v 1.10 2013/05/17 00:13:13 djm Exp $ */
+/* $OpenBSD: auth2-passwd.c,v 1.11 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  *
@@ -59,7 +59,7 @@ userauth_passwd(Authctxt *authctxt)
         if (change) {
                 /* discard new password from packet */
                 newpass = packet_get_string(&newlen);
-                memset(newpass, 0, newlen);
+                explicit_bzero(newpass, newlen);
                 free(newpass);
         }
         packet_check_eom();
@@ -68,7 +68,7 @@ userauth_passwd(Authctxt *authctxt)
                 logit("password change not supported");
         else if (PRIVSEP(auth_password(authctxt, password)) == 1)
                 authenticated = 1;
-        memset(password, 0, len);
+        explicit_bzero(password, len);
         free(password);
         return authenticated;
 }
diff --git a/authfile.c b/authfile.c
index 22da0eb05..d7eaa9dec 100644
--- a/authfile.c
+++ b/authfile.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: authfile.c,v 1.102 2014/01/31 16:39:19 tedu Exp $ */
+/* $OpenBSD: authfile.c,v 1.103 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -131,7 +131,7 @@ key_private_to_blob2(Key *prv, Buffer *blob, const char *passphrase,
                 buffer_put_int(&kdf, rounds);
         }
         cipher_init(&ctx, c, key, keylen, key + keylen , ivlen, 1);
-        memset(key, 0, keylen + ivlen);
+        explicit_bzero(key, keylen + ivlen);
         free(key);
 
         buffer_init(&encoded);
@@ -143,7 +143,7 @@ key_private_to_blob2(Key *prv, Buffer *blob, const char *passphrase,
         key_to_blob(prv, &cp, &len);                    /* public key */
         buffer_put_string(&encoded, cp, len);
 
-        memset(cp, 0, len);
+        explicit_bzero(cp, len);
         free(cp);
 
         buffer_free(&kdf);
@@ -409,7 +409,7 @@ key_parse_private2(Buffer *blob, int type, const char *passphrase,
         free(salt);
         free(comment);
         if (key)
-                memset(key, 0, keylen + ivlen);
+                explicit_bzero(key, keylen + ivlen);
         free(key);
         buffer_free(&encoded);
         buffer_free(&copy);
@@ -496,10 +496,10 @@ key_private_rsa1_to_blob(Key *key, Buffer *blob, const char *passphrase,
             buffer_ptr(&buffer), buffer_len(&buffer), 0, 0) != 0)
                 fatal("%s: cipher_crypt failed", __func__);
         cipher_cleanup(&ciphercontext);
-        memset(&ciphercontext, 0, sizeof(ciphercontext));
+        explicit_bzero(&ciphercontext, sizeof(ciphercontext));
 
         /* Destroy temporary data. */
-        memset(buf, 0, sizeof(buf));
+        explicit_bzero(buf, sizeof(buf));
         buffer_free(&buffer);
 
         buffer_append(blob, buffer_ptr(&encrypted), buffer_len(&encrypted));
@@ -831,7 +831,7 @@ key_parse_private_rsa1(Buffer *blob, const char *passphrase, char **commentp)
             buffer_ptr(&copy), buffer_len(&copy), 0, 0) != 0)
                 fatal("%s: cipher_crypt failed", __func__);
         cipher_cleanup(&ciphercontext);
-        memset(&ciphercontext, 0, sizeof(ciphercontext));
+        explicit_bzero(&ciphercontext, sizeof(ciphercontext));
         buffer_free(&copy);
 
         check1 = buffer_get_char(&decrypted);
diff --git a/bufaux.c b/bufaux.c
index f1f14b33d..e24b5fc0a 100644
--- a/bufaux.c
+++ b/bufaux.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: bufaux.c,v 1.55 2014/01/31 16:39:19 tedu Exp $ */
+/* $OpenBSD: bufaux.c,v 1.56 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -346,7 +346,7 @@ buffer_get_bignum2_as_string_ret(Buffer *buffer, u_int *length_ptr)
         }
         ret = xmalloc(len);
         memcpy(ret, p, len);
-        memset(p, '\0', len);
+        explicit_bzero(p, len);
         free(bin);
         return ret;
 }
@@ -383,7 +383,7 @@ buffer_put_bignum2_from_string(Buffer *buffer, const u_char *s, u_int l)
         }
         memcpy(p, s, l);
         buffer_put_string(buffer, buf, l + pad);
-        memset(buf, '\0', l + pad);
+        explicit_bzero(buf, l + pad);
         free(buf);
 }
 
diff --git a/bufbn.c b/bufbn.c
index 2ebc80a27..c4ad810e4 100644
--- a/bufbn.c
+++ b/bufbn.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: bufbn.c,v 1.8 2013/11/08 11:15:19 dtucker Exp $*/
+/* $OpenBSD: bufbn.c,v 1.9 2014/02/02 03:44:31 djm Exp $*/
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -80,7 +80,7 @@ buffer_put_bignum_ret(Buffer *buffer, const BIGNUM *value)
         /* Store the binary data. */
         buffer_append(buffer, buf, oi);
 
-        memset(buf, 0, bin_size);
+        explicit_bzero(buf, bin_size);
         free(buf);
 
         return (0);
@@ -173,7 +173,7 @@ buffer_put_bignum2_ret(Buffer *buffer, const BIGNUM *value)
         }
         hasnohigh = (buf[1] & 0x80) ? 0 : 1;
         buffer_put_string(buffer, buf+hasnohigh, bytes-hasnohigh);
-        memset(buf, 0, bytes);
+        explicit_bzero(buf, bytes);
         free(buf);
         return (0);
 }
diff --git a/buffer.c b/buffer.c
index 9e7c40a5a..d240f6753 100644
--- a/buffer.c
+++ b/buffer.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: buffer.c,v 1.34 2013/11/08 11:15:19 dtucker Exp $ */
+/* $OpenBSD: buffer.c,v 1.35 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -49,7 +49,7 @@ void
 buffer_free(Buffer *buffer)
 {
         if (buffer->alloc > 0) {
-                memset(buffer->buf, 0, buffer->alloc);
+                explicit_bzero(buffer->buf, buffer->alloc);
                 buffer->alloc = 0;
                 free(buffer->buf);
         }
diff --git a/cipher-3des1.c b/cipher-3des1.c
index 56fc77786..b2823592b 100644
--- a/cipher-3des1.c
+++ b/cipher-3des1.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: cipher-3des1.c,v 1.9 2013/11/08 00:39:15 djm Exp $ */
+/* $OpenBSD: cipher-3des1.c,v 1.10 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Copyright (c) 2003 Markus Friedl.  All rights reserved.
  *
@@ -93,7 +93,7 @@ ssh1_3des_init(EVP_CIPHER_CTX *ctx, const u_char *key, const u_char *iv,
         if (EVP_CipherInit(&c->k1, EVP_des_cbc(), k1, NULL, enc) == 0 ||
             EVP_CipherInit(&c->k2, EVP_des_cbc(), k2, NULL, !enc) == 0 ||
             EVP_CipherInit(&c->k3, EVP_des_cbc(), k3, NULL, enc) == 0) {
-                memset(c, 0, sizeof(*c));
+                explicit_bzero(c, sizeof(*c));
                 free(c);
                 EVP_CIPHER_CTX_set_app_data(ctx, NULL);
                 return (0);
@@ -134,7 +134,7 @@ ssh1_3des_cleanup(EVP_CIPHER_CTX *ctx)
                 EVP_CIPHER_CTX_cleanup(&c->k1);
                 EVP_CIPHER_CTX_cleanup(&c->k2);
                 EVP_CIPHER_CTX_cleanup(&c->k3);
-                memset(c, 0, sizeof(*c));
+                explicit_bzero(c, sizeof(*c));
                 free(c);
                 EVP_CIPHER_CTX_set_app_data(ctx, NULL);
         }
diff --git a/cipher.c b/cipher.c
index 98961be1a..ee79a1ef4 100644
--- a/cipher.c
+++ b/cipher.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: cipher.c,v 1.95 2014/01/27 19:18:54 markus Exp $ */
+/* $OpenBSD: cipher.c,v 1.96 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -337,7 +337,7 @@ cipher_init(CipherContext *cc, const Cipher *cipher,
                 if (EVP_Cipher(&cc->evp, discard, junk,
                     cipher->discard_len) == 0)
                         fatal("evp_crypt: EVP_Cipher failed during discard");
-                memset(discard, 0, cipher->discard_len);
+                explicit_bzero(discard, cipher->discard_len);
                 free(junk);
                 free(discard);
         }
@@ -422,7 +422,7 @@ void
 cipher_cleanup(CipherContext *cc)
 {
         if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0)
-                memset(&cc->cp_ctx, 0, sizeof(cc->cp_ctx));
+                explicit_bzero(&cc->cp_ctx, sizeof(cc->cp_ctx));
         else if (EVP_CIPHER_CTX_cleanup(&cc->evp) == 0)
                 error("cipher_cleanup: EVP_CIPHER_CTX_cleanup failed");
 }
@@ -444,7 +444,7 @@ cipher_set_key_string(CipherContext *cc, const Cipher *cipher,
 
         cipher_init(cc, cipher, digest, 16, NULL, 0, do_encrypt);
 
-        memset(digest, 0, sizeof(digest));
+        explicit_bzero(digest, sizeof(digest));
 }
 
 /*
diff --git a/clientloop.c b/clientloop.c
index fd3ff49e8..59ad3a2c3 100644
--- a/clientloop.c
+++ b/clientloop.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: clientloop.c,v 1.257 2014/01/31 16:39:19 tedu Exp $ */
+/* $OpenBSD: clientloop.c,v 1.258 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -1761,7 +1761,7 @@ client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
         char *data = packet_get_string(&data_len);
         packet_check_eom();
         buffer_append(&stdout_buffer, data, data_len);
-        memset(data, 0, data_len);
+        explicit_bzero(data, data_len);
         free(data);
 }
 static void
@@ -1771,7 +1771,7 @@ client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
         char *data = packet_get_string(&data_len);
         packet_check_eom();
         buffer_append(&stderr_buffer, data, data_len);
-        memset(data, 0, data_len);
+        explicit_bzero(data, data_len);
         free(data);
 }
 static void
diff --git a/gss-serv.c b/gss-serv.c
index 95348e251..b61e6e140 100644
--- a/gss-serv.c
+++ b/gss-serv.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: gss-serv.c,v 1.24 2013/07/20 01:55:13 djm Exp $ */
+/* $OpenBSD: gss-serv.c,v 1.25 2014/02/02 03:44:31 djm Exp $ */
 
 /*
  * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
@@ -346,7 +346,8 @@ ssh_gssapi_userok(char *user)
                         gss_release_buffer(&lmin, &gssapi_client.displayname);
                         gss_release_buffer(&lmin, &gssapi_client.exportedname);
                         gss_release_cred(&lmin, &gssapi_client.creds);
-                        memset(&gssapi_client, 0, sizeof(ssh_gssapi_client));
+                        explicit_bzero(&gssapi_client,
+                            sizeof(ssh_gssapi_client));
                         return 0;
                 }
         else
diff --git a/kex.c b/kex.c
index 616484b85..74e2b8682 100644
--- a/kex.c
+++ b/kex.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kex.c,v 1.97 2014/01/25 20:35:37 markus Exp $ */
+/* $OpenBSD: kex.c,v 1.98 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
  *
@@ -666,8 +666,8 @@ derive_ssh1_session_id(BIGNUM *host_modulus, BIGNUM *server_modulus,
                 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));
+        explicit_bzero(nbuf, sizeof(nbuf));
+        explicit_bzero(obuf, sizeof(obuf));
 }
 
 #if defined(DEBUG_KEX) || defined(DEBUG_KEXDH) || defined(DEBUG_KEXECDH)
diff --git a/kexdhc.c b/kexdhc.c
index 78509af21..f7a19fc13 100644
--- a/kexdhc.c
+++ b/kexdhc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexdhc.c,v 1.14 2014/01/12 08:13:13 djm Exp $ */
+/* $OpenBSD: kexdhc.c,v 1.15 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  *
@@ -124,7 +124,7 @@ kexdh_client(Kex *kex)
                 fatal("kexdh_client: BN_new failed");
         if (BN_bin2bn(kbuf, kout, shared_secret) == NULL)
                 fatal("kexdh_client: BN_bin2bn failed");
-        memset(kbuf, 0, klen);
+        explicit_bzero(kbuf, klen);
         free(kbuf);
 
         /* calc and verify H */
diff --git a/kexdhs.c b/kexdhs.c
index d2c7adc96..c3011f741 100644
--- a/kexdhs.c
+++ b/kexdhs.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexdhs.c,v 1.17 2014/01/12 08:13:13 djm Exp $ */
+/* $OpenBSD: kexdhs.c,v 1.18 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  *
@@ -110,7 +110,7 @@ kexdh_server(Kex *kex)
                 fatal("kexdh_server: BN_new failed");
         if (BN_bin2bn(kbuf, kout, shared_secret) == NULL)
                 fatal("kexdh_server: BN_bin2bn failed");
-        memset(kbuf, 0, klen);
+        explicit_bzero(kbuf, klen);
         free(kbuf);
 
         key_to_blob(server_host_public, &server_host_key_blob, &sbloblen);
diff --git a/kexecdhc.c b/kexecdhc.c
index e3d1cf5f9..2f7629cca 100644
--- a/kexecdhc.c
+++ b/kexecdhc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexecdhc.c,v 1.6 2014/01/12 08:13:13 djm Exp $ */
+/* $OpenBSD: kexecdhc.c,v 1.7 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  * Copyright (c) 2010 Damien Miller.  All rights reserved.
@@ -119,7 +119,7 @@ kexecdh_client(Kex *kex)
                 fatal("%s: BN_new failed", __func__);
         if (BN_bin2bn(kbuf, klen, shared_secret) == NULL)
                 fatal("%s: BN_bin2bn failed", __func__);
-        memset(kbuf, 0, klen);
+        explicit_bzero(kbuf, klen);
         free(kbuf);
 
         /* calc and verify H */
diff --git a/kexecdhs.c b/kexecdhs.c
index 6fbb79c9d..2700b7219 100644
--- a/kexecdhs.c
+++ b/kexecdhs.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexecdhs.c,v 1.9 2014/01/12 08:13:13 djm Exp $ */
+/* $OpenBSD: kexecdhs.c,v 1.10 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  * Copyright (c) 2010 Damien Miller.  All rights reserved.
@@ -103,7 +103,7 @@ kexecdh_server(Kex *kex)
                 fatal("%s: BN_new failed", __func__);
         if (BN_bin2bn(kbuf, klen, shared_secret) == NULL)
                 fatal("%s: BN_bin2bn failed", __func__);
-        memset(kbuf, 0, klen);
+        explicit_bzero(kbuf, klen);
         free(kbuf);
 
         /* calc H */
diff --git a/kexgexc.c b/kexgexc.c
index 629b5fbbc..355b7ba31 100644
--- a/kexgexc.c
+++ b/kexgexc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexgexc.c,v 1.16 2014/01/25 10:12:50 dtucker Exp $ */
+/* $OpenBSD: kexgexc.c,v 1.17 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Copyright (c) 2000 Niels Provos.  All rights reserved.
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
@@ -162,7 +162,7 @@ kexgex_client(Kex *kex)
                 fatal("kexgex_client: BN_new failed");
         if (BN_bin2bn(kbuf, kout, shared_secret) == NULL)
                 fatal("kexgex_client: BN_bin2bn failed");
-        memset(kbuf, 0, klen);
+        explicit_bzero(kbuf, klen);
         free(kbuf);
 
         if (datafellows & SSH_OLD_DHGEX)
diff --git a/kexgexs.c b/kexgexs.c
index 8773778ed..770ad28a8 100644
--- a/kexgexs.c
+++ b/kexgexs.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexgexs.c,v 1.18 2014/01/12 08:13:13 djm Exp $ */
+/* $OpenBSD: kexgexs.c,v 1.19 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Copyright (c) 2000 Niels Provos.  All rights reserved.
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
@@ -150,7 +150,7 @@ kexgex_server(Kex *kex)
                 fatal("kexgex_server: BN_new failed");
         if (BN_bin2bn(kbuf, kout, shared_secret) == NULL)
                 fatal("kexgex_server: BN_bin2bn failed");
-        memset(kbuf, 0, klen);
+        explicit_bzero(kbuf, klen);
         free(kbuf);
 
         key_to_blob(server_host_public, &server_host_key_blob, &sbloblen);
diff --git a/key.c b/key.c
index 914233808..168e1b7d7 100644
--- a/key.c
+++ b/key.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: key.c,v 1.115 2014/01/09 23:20:00 djm Exp $ */
+/* $OpenBSD: key.c,v 1.116 2014/02/02 03:44:31 djm Exp $ */
 /*
  * read_bignum():
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -242,12 +242,12 @@ key_free(Key *k)
         case KEY_ED25519:
         case KEY_ED25519_CERT:
                 if (k->ed25519_pk) {
-                        memset(k->ed25519_pk, 0, ED25519_PK_SZ);
+                        explicit_bzero(k->ed25519_pk, ED25519_PK_SZ);
                         free(k->ed25519_pk);
                         k->ed25519_pk = NULL;
                 }
                 if (k->ed25519_sk) {
-                        memset(k->ed25519_sk, 0, ED25519_SK_SZ);
+                        explicit_bzero(k->ed25519_sk, ED25519_SK_SZ);
                         free(k->ed25519_sk);
                         k->ed25519_sk = NULL;
                 }
@@ -415,7 +415,7 @@ key_fingerprint_raw(const Key *k, enum fp_type dgst_type,
                 if ((ssh_digest_memory(hash_alg, blob, len,
                     retval, SSH_DIGEST_MAX_LENGTH)) != 0)
                         fatal("%s: digest_memory failed", __func__);
-                memset(blob, 0, len);
+                explicit_bzero(blob, len);
                 free(blob);
                 *dgst_raw_length = ssh_digest_bytes(hash_alg);
         } else {
@@ -623,7 +623,7 @@ key_fingerprint(const Key *k, enum fp_type dgst_type, enum fp_rep dgst_rep)
                     dgst_rep);
                 break;
         }
-        memset(dgst_raw, 0, dgst_raw_len);
+        explicit_bzero(dgst_raw, dgst_raw_len);
         free(dgst_raw);
         return retval;
 }
@@ -1744,7 +1744,7 @@ to_blob(const Key *key, u_char **blobp, u_int *lenp, int force_plain)
                 *blobp = xmalloc(len);
                 memcpy(*blobp, buffer_ptr(&b), len);
         }
-        memset(buffer_ptr(&b), 0, len);
+        explicit_bzero(buffer_ptr(&b), len);
         buffer_free(&b);
         return len;
 }
diff --git a/monitor.c b/monitor.c
index 79bd7c0c4..531c4f9a8 100644
--- a/monitor.c
+++ b/monitor.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: monitor.c,v 1.130 2014/01/31 16:39:19 tedu Exp $ */
+/* $OpenBSD: monitor.c,v 1.131 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Copyright 2002 Niels Provos <provos@citi.umich.edu>
  * Copyright 2002 Markus Friedl <markus@openbsd.org>
@@ -858,7 +858,7 @@ mm_answer_authpassword(int sock, Buffer *m)
         /* Only authenticate if the context is valid */
         authenticated = options.password_authentication &&
             auth_password(authctxt, passwd);
-        memset(passwd, 0, strlen(passwd));
+        explicit_bzero(passwd, strlen(passwd));
         free(passwd);
 
         buffer_clear(m);
@@ -1800,13 +1800,13 @@ monitor_apply_keystate(struct monitor *pmonitor)
         /* XXX inefficient for large buffers, need: buffer_init_from_string */
         buffer_clear(packet_get_input());
         buffer_append(packet_get_input(), child_state.input, child_state.ilen);
-        memset(child_state.input, 0, child_state.ilen);
+        explicit_bzero(child_state.input, child_state.ilen);
         free(child_state.input);
 
         buffer_clear(packet_get_output());
         buffer_append(packet_get_output(), child_state.output,
                       child_state.olen);
-        memset(child_state.output, 0, child_state.olen);
+        explicit_bzero(child_state.output, child_state.olen);
         free(child_state.output);
 
         /* Roaming */
diff --git a/monitor_wrap.c b/monitor_wrap.c
index 64c262363..1a47e4174 100644
--- a/monitor_wrap.c
+++ b/monitor_wrap.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: monitor_wrap.c,v 1.78 2014/01/29 06:18:35 djm Exp $ */
+/* $OpenBSD: monitor_wrap.c,v 1.79 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Copyright 2002 Niels Provos <provos@citi.umich.edu>
  * Copyright 2002 Markus Friedl <markus@openbsd.org>
@@ -572,7 +572,7 @@ mm_newkeys_to_blob(int mode, u_char **blobp, u_int *lenp)
                 *blobp = xmalloc(len);
                 memcpy(*blobp, buffer_ptr(&b), len);
         }
-        memset(buffer_ptr(&b), 0, len);
+        explicit_bzero(buffer_ptr(&b), len);
         buffer_free(&b);
         return len;
 }
@@ -616,7 +616,7 @@ mm_send_keystate(struct monitor *monitor)
                 key = xmalloc(keylen+1);        /* add 1 if keylen == 0 */
                 keylen = packet_get_encryption_key(key);
                 buffer_put_string(&m, key, keylen);
-                memset(key, 0, keylen);
+                explicit_bzero(key, keylen);
                 free(key);
 
                 ivlen = packet_get_keyiv_len(MODE_OUT);
diff --git a/packet.c b/packet.c
index 6cf7edbb8..54c0558f9 100644
--- a/packet.c
+++ b/packet.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: packet.c,v 1.191 2013/12/06 13:34:54 markus Exp $ */
+/* $OpenBSD: packet.c,v 1.192 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -764,9 +764,9 @@ set_newkeys(int mode)
                 mac  = &active_state->newkeys[mode]->mac;
                 comp = &active_state->newkeys[mode]->comp;
                 mac_clear(mac);
-                memset(enc->iv,  0, enc->iv_len);
-                memset(enc->key, 0, enc->key_len);
-                memset(mac->key, 0, mac->key_len);
+                explicit_bzero(enc->iv,  enc->iv_len);
+                explicit_bzero(enc->key, enc->key_len);
+                explicit_bzero(mac->key, mac->key_len);
                 free(enc->name);
                 free(enc->iv);
                 free(enc->key);
@@ -787,9 +787,9 @@ set_newkeys(int mode)
         cipher_init(cc, enc->cipher, enc->key, enc->key_len,
             enc->iv, enc->iv_len, crypt_type);
         /* Deleting the keys does not gain extra security */
-        /* memset(enc->iv,  0, enc->block_size);
-           memset(enc->key, 0, enc->key_len);
-           memset(mac->key, 0, mac->key_len); */
+        /* explicit_bzero(enc->iv,  enc->block_size);
+           explicit_bzero(enc->key, enc->key_len);
+           explicit_bzero(mac->key, mac->key_len); */
         if ((comp->type == COMP_ZLIB ||
             (comp->type == COMP_DELAYED &&
              active_state->after_authentication)) && comp->enabled == 0) {
@@ -928,7 +928,7 @@ packet_send2_wrapped(void)
                 }
         } else {
                 /* clear padding */
-                memset(cp, 0, padlen);
+                explicit_bzero(cp, padlen);
         }
         /* sizeof (packet_len + pad_len + payload + padding) */
         len = buffer_len(&active_state->outgoing_packet);
diff --git a/readpass.c b/readpass.c
index e37d31158..869d86425 100644
--- a/readpass.c
+++ b/readpass.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: readpass.c,v 1.49 2013/05/17 00:13:14 djm Exp $ */
+/* $OpenBSD: readpass.c,v 1.50 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  *
@@ -99,13 +99,13 @@ ssh_askpass(char *askpass, const char *msg)
                         break;
         signal(SIGCHLD, osigchld);
         if (ret == -1 || !WIFEXITED(status) || WEXITSTATUS(status) != 0) {
-                memset(buf, 0, sizeof(buf));
+                explicit_bzero(buf, sizeof(buf));
                 return NULL;
         }
 
         buf[strcspn(buf, "\r\n")] = '\0';
         pass = xstrdup(buf);
-        memset(buf, 0, sizeof(buf));
+        explicit_bzero(buf, sizeof(buf));
         return pass;
 }
 
@@ -162,7 +162,7 @@ read_passphrase(const char *prompt, int flags)
         }
 
         ret = xstrdup(buf);
-        memset(buf, 'x', sizeof buf);
+        explicit_bzero(buf, sizeof(buf));
         return ret;
 }
 
diff --git a/rsa.c b/rsa.c
index a9ee6b0ed..d0b5bbf5e 100644
--- a/rsa.c
+++ b/rsa.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: rsa.c,v 1.30 2013/05/17 00:13:14 djm Exp $ */
+/* $OpenBSD: rsa.c,v 1.31 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -94,8 +94,8 @@ rsa_public_encrypt(BIGNUM *out, BIGNUM *in, RSA *key)
         if (BN_bin2bn(outbuf, len, out) == NULL)
                 fatal("rsa_public_encrypt: BN_bin2bn failed");
 
-        memset(outbuf, 0, olen);
-        memset(inbuf, 0, ilen);
+        explicit_bzero(outbuf, olen);
+        explicit_bzero(inbuf, ilen);
         free(outbuf);
         free(inbuf);
 }
@@ -120,8 +120,8 @@ rsa_private_decrypt(BIGNUM *out, BIGNUM *in, RSA *key)
                 if (BN_bin2bn(outbuf, len, out) == NULL)
                         fatal("rsa_private_decrypt: BN_bin2bn failed");
         }
-        memset(outbuf, 0, olen);
-        memset(inbuf, 0, ilen);
+        explicit_bzero(outbuf, olen);
+        explicit_bzero(inbuf, ilen);
         free(outbuf);
         free(inbuf);
         return len;
diff --git a/serverloop.c b/serverloop.c
index 5b2f8028d..2f8e3a06a 100644
--- a/serverloop.c
+++ b/serverloop.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: serverloop.c,v 1.169 2013/12/19 00:19:12 dtucker Exp $ */
+/* $OpenBSD: serverloop.c,v 1.170 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -920,7 +920,7 @@ server_input_stdin_data(int type, u_int32_t seq, void *ctxt)
         data = packet_get_string(&data_len);
         packet_check_eom();
         buffer_append(&stdin_buffer, data, data_len);
-        memset(data, 0, data_len);
+        explicit_bzero(data, data_len);
         free(data);
 }
 
diff --git a/ssh-add.c b/ssh-add.c
index 63ce72083..3421452af 100644
--- a/ssh-add.c
+++ b/ssh-add.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-add.c,v 1.108 2013/12/19 00:10:30 djm Exp $ */
+/* $OpenBSD: ssh-add.c,v 1.109 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -90,7 +90,7 @@ static void
 clear_pass(void)
 {
         if (pass) {
-                memset(pass, 0, strlen(pass));
+                explicit_bzero(pass, strlen(pass));
                 free(pass);
                 pass = NULL;
         }
@@ -366,7 +366,7 @@ lock_agent(AuthenticationConnection *ac, int lock)
                         fprintf(stderr, "Passwords do not match.\n");
                         passok = 0;
                 }
-                memset(p2, 0, strlen(p2));
+                explicit_bzero(p2, strlen(p2));
                 free(p2);
         }
         if (passok && ssh_lock_agent(ac, lock, p1)) {
@@ -374,7 +374,7 @@ lock_agent(AuthenticationConnection *ac, int lock)
                 ret = 0;
         } else
                 fprintf(stderr, "Failed to %slock agent.\n", lock ? "" : "un");
-        memset(p1, 0, strlen(p1));
+        explicit_bzero(p1, strlen(p1));
         free(p1);
         return (ret);
 }
diff --git a/ssh-agent.c b/ssh-agent.c
index 256dff50c..ba2461211 100644
--- a/ssh-agent.c
+++ b/ssh-agent.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-agent.c,v 1.182 2014/01/27 19:18:54 markus Exp $ */
+/* $OpenBSD: ssh-agent.c,v 1.183 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -554,7 +554,7 @@ process_lock_agent(SocketEntry *e, int lock)
         passwd = buffer_get_string(&e->request, NULL);
         if (locked && !lock && strcmp(passwd, lock_passwd) == 0) {
                 locked = 0;
-                memset(lock_passwd, 0, strlen(lock_passwd));
+                explicit_bzero(lock_passwd, strlen(lock_passwd));
                 free(lock_passwd);
                 lock_passwd = NULL;
                 success = 1;
@@ -563,7 +563,7 @@ process_lock_agent(SocketEntry *e, int lock)
                 lock_passwd = xstrdup(passwd);
                 success = 1;
         }
-        memset(passwd, 0, strlen(passwd));
+        explicit_bzero(passwd, strlen(passwd));
         free(passwd);
 
         buffer_put_int(&e->output, 1);
diff --git a/ssh-dss.c b/ssh-dss.c
index 7b897475c..6b4abcb7d 100644
--- a/ssh-dss.c
+++ b/ssh-dss.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-dss.c,v 1.30 2014/01/09 23:20:00 djm Exp $ */
+/* $OpenBSD: ssh-dss.c,v 1.31 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  *
@@ -65,7 +65,7 @@ ssh_dss_sign(const Key *key, u_char **sigp, u_int *lenp,
         }
 
         sig = DSA_do_sign(digest, dlen, key->dsa);
-        memset(digest, 'd', sizeof(digest));
+        explicit_bzero(digest, sizeof(digest));
 
         if (sig == NULL) {
                 error("ssh_dss_sign: sign failed");
@@ -79,7 +79,7 @@ ssh_dss_sign(const Key *key, u_char **sigp, u_int *lenp,
                 DSA_SIG_free(sig);
                 return -1;
         }
-        memset(sigblob, 0, SIGBLOB_LEN);
+        explicit_bzero(sigblob, SIGBLOB_LEN);
         BN_bn2bin(sig->r, sigblob+ SIGBLOB_LEN - INTBLOB_LEN - rlen);
         BN_bn2bin(sig->s, sigblob+ SIGBLOB_LEN - slen);
         DSA_SIG_free(sig);
@@ -168,7 +168,7 @@ ssh_dss_verify(const Key *key, const u_char *signature, u_int signaturelen,
                 fatal("%s: BN_bin2bn failed", __func__);
 
         /* clean up */
-        memset(sigblob, 0, len);
+        explicit_bzero(sigblob, len);
         free(sigblob);
 
         /* sha1 the data */
@@ -179,7 +179,7 @@ ssh_dss_verify(const Key *key, const u_char *signature, u_int signaturelen,
         }
 
         ret = DSA_do_verify(digest, dlen, sig, key->dsa);
-        memset(digest, 'd', sizeof(digest));
+        explicit_bzero(digest, sizeof(digest));
 
         DSA_SIG_free(sig);
 
diff --git a/ssh-ecdsa.c b/ssh-ecdsa.c
index 10ad9da60..95b222446 100644
--- a/ssh-ecdsa.c
+++ b/ssh-ecdsa.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-ecdsa.c,v 1.8 2014/01/09 23:20:00 djm Exp $ */
+/* $OpenBSD: ssh-ecdsa.c,v 1.9 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  * Copyright (c) 2010 Damien Miller.  All rights reserved.
@@ -72,7 +72,7 @@ ssh_ecdsa_sign(const Key *key, u_char **sigp, u_int *lenp,
         }
 
         sig = ECDSA_do_sign(digest, dlen, key->ecdsa);
-        memset(digest, 'd', sizeof(digest));
+        explicit_bzero(digest, sizeof(digest));
 
         if (sig == NULL) {
                 error("%s: sign failed", __func__);
@@ -153,7 +153,7 @@ ssh_ecdsa_verify(const Key *key, const u_char *signature, u_int signaturelen,
         buffer_free(&bb);
 
         /* clean up */
-        memset(sigblob, 0, len);
+        explicit_bzero(sigblob, len);
         free(sigblob);
 
         /* hash the data */
@@ -169,7 +169,7 @@ ssh_ecdsa_verify(const Key *key, const u_char *signature, u_int signaturelen,
         }
 
         ret = ECDSA_do_verify(digest, dlen, sig, key->ecdsa);
-        memset(digest, 'd', sizeof(digest));
+        explicit_bzero(digest, sizeof(digest));
 
         ECDSA_SIG_free(sig);
 
diff --git a/ssh-ed25519.c b/ssh-ed25519.c
index 1aedcf83a..56c480df2 100644
--- a/ssh-ed25519.c
+++ b/ssh-ed25519.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-ed25519.c,v 1.1 2013/12/06 13:39:49 markus Exp $ */
+/* $OpenBSD: ssh-ed25519.c,v 1.2 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Copyright (c) 2013 Markus Friedl <markus@openbsd.org>
  *
@@ -66,7 +66,7 @@ ssh_ed25519_sign(const Key *key, u_char **sigp, u_int *lenp,
                 memcpy(*sigp, buffer_ptr(&b), len);
         }
         buffer_free(&b);
-        memset(sig, 's', slen);
+        explicit_bzero(sig, slen);
         free(sig);
 
         return 0;
@@ -130,9 +130,9 @@ ssh_ed25519_verify(const Key *key, const u_char *signature, u_int signaturelen,
         }
         /* XXX compare 'm' and 'data' ? */
 
-        memset(sigblob, 's', len);
-        memset(sm, 'S', smlen);
-        memset(m, 'm', smlen); /* NB. mlen may be invalid if ret != 0 */
+        explicit_bzero(sigblob, len);
+        explicit_bzero(sm, smlen);
+        explicit_bzero(m, smlen); /* NB. mlen may be invalid if ret != 0 */
         free(sigblob);
         free(sm);
         free(m);
diff --git a/ssh-keygen.c b/ssh-keygen.c
index 8140447f7..9f0310945 100644
--- a/ssh-keygen.c
+++ b/ssh-keygen.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-keygen.c,v 1.239 2014/01/31 16:39:19 tedu Exp $ */
+/* $OpenBSD: ssh-keygen.c,v 1.240 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1994 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -267,7 +267,7 @@ load_identity(char *filename)
                         pass = read_passphrase("Enter passphrase: ",
                             RP_ALLOW_STDIN);
                 prv = key_load_private(filename, pass, NULL);
-                memset(pass, 0, strlen(pass));
+                explicit_bzero(pass, strlen(pass));
                 free(pass);
         }
         return prv;
@@ -1258,7 +1258,7 @@ do_change_passphrase(struct passwd *pw)
                             RP_ALLOW_STDIN);
                 private = key_load_private(identity_file, old_passphrase,
                     &comment);
-                memset(old_passphrase, 0, strlen(old_passphrase));
+                explicit_bzero(old_passphrase, strlen(old_passphrase));
                 free(old_passphrase);
                 if (private == NULL) {
                         printf("Bad passphrase.\n");
@@ -1280,15 +1280,15 @@ do_change_passphrase(struct passwd *pw)
 
                 /* Verify that they are the same. */
                 if (strcmp(passphrase1, passphrase2) != 0) {
-                        memset(passphrase1, 0, strlen(passphrase1));
-                        memset(passphrase2, 0, strlen(passphrase2));
+                        explicit_bzero(passphrase1, strlen(passphrase1));
+                        explicit_bzero(passphrase2, strlen(passphrase2));
                         free(passphrase1);
                         free(passphrase2);
                         printf("Pass phrases do not match.  Try again.\n");
                         exit(1);
                 }
                 /* Destroy the other copy. */
-                memset(passphrase2, 0, strlen(passphrase2));
+                explicit_bzero(passphrase2, strlen(passphrase2));
                 free(passphrase2);
         }
 
@@ -1296,14 +1296,14 @@ do_change_passphrase(struct passwd *pw)
         if (!key_save_private(private, identity_file, passphrase1, comment,
             use_new_format, new_format_cipher, rounds)) {
                 printf("Saving the key failed: %s.\n", identity_file);
-                memset(passphrase1, 0, strlen(passphrase1));
+                explicit_bzero(passphrase1, strlen(passphrase1));
                 free(passphrase1);
                 key_free(private);
                 free(comment);
                 exit(1);
         }
         /* Destroy the passphrase and the copy of the key in memory. */
-        memset(passphrase1, 0, strlen(passphrase1));
+        explicit_bzero(passphrase1, strlen(passphrase1));
         free(passphrase1);
         key_free(private);               /* Destroys contents */
         free(comment);
@@ -1375,7 +1375,7 @@ do_change_comment(struct passwd *pw)
                 /* Try to load using the passphrase. */
                 private = key_load_private(identity_file, passphrase, &comment);
                 if (private == NULL) {
-                        memset(passphrase, 0, strlen(passphrase));
+                        explicit_bzero(passphrase, strlen(passphrase));
                         free(passphrase);
                         printf("Bad passphrase.\n");
                         exit(1);
@@ -1396,7 +1396,7 @@ do_change_comment(struct passwd *pw)
                 printf("Enter new comment: ");
                 fflush(stdout);
                 if (!fgets(new_comment, sizeof(new_comment), stdin)) {
-                        memset(passphrase, 0, strlen(passphrase));
+                        explicit_bzero(passphrase, strlen(passphrase));
                         key_free(private);
                         exit(1);
                 }
@@ -1407,13 +1407,13 @@ do_change_comment(struct passwd *pw)
         if (!key_save_private(private, identity_file, passphrase, new_comment,
             use_new_format, new_format_cipher, rounds)) {
                 printf("Saving the key failed: %s.\n", identity_file);
-                memset(passphrase, 0, strlen(passphrase));
+                explicit_bzero(passphrase, strlen(passphrase));
                 free(passphrase);
                 key_free(private);
                 free(comment);
                 exit(1);
         }
-        memset(passphrase, 0, strlen(passphrase));
+        explicit_bzero(passphrase, strlen(passphrase));
         free(passphrase);
         public = key_from_private(private);
         key_free(private);
@@ -2632,15 +2632,15 @@ passphrase_again:
                          * The passphrases do not match.  Clear them and
                          * retry.
                          */
-                        memset(passphrase1, 0, strlen(passphrase1));
-                        memset(passphrase2, 0, strlen(passphrase2));
+                        explicit_bzero(passphrase1, strlen(passphrase1));
+                        explicit_bzero(passphrase2, strlen(passphrase2));
                         free(passphrase1);
                         free(passphrase2);
                         printf("Passphrases do not match.  Try again.\n");
                         goto passphrase_again;
                 }
                 /* Clear the other copy of the passphrase. */
-                memset(passphrase2, 0, strlen(passphrase2));
+                explicit_bzero(passphrase2, strlen(passphrase2));
                 free(passphrase2);
         }
 
@@ -2655,12 +2655,12 @@ passphrase_again:
         if (!key_save_private(private, identity_file, passphrase1, comment,
             use_new_format, new_format_cipher, rounds)) {
                 printf("Saving the key failed: %s.\n", identity_file);
-                memset(passphrase1, 0, strlen(passphrase1));
+                explicit_bzero(passphrase1, strlen(passphrase1));
                 free(passphrase1);
                 exit(1);
         }
         /* Clear the passphrase. */
-        memset(passphrase1, 0, strlen(passphrase1));
+        explicit_bzero(passphrase1, strlen(passphrase1));
         free(passphrase1);
 
         /* Clear the private key and the random number generator. */
diff --git a/ssh-rsa.c b/ssh-rsa.c
index a2112d033..c6f25b3ee 100644
--- a/ssh-rsa.c
+++ b/ssh-rsa.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-rsa.c,v 1.50 2014/01/09 23:20:00 djm Exp $ */
+/* $OpenBSD: ssh-rsa.c,v 1.51 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Copyright (c) 2000, 2003 Markus Friedl <markus@openbsd.org>
  *
@@ -70,7 +70,7 @@ ssh_rsa_sign(const Key *key, u_char **sigp, u_int *lenp,
         sig = xmalloc(slen);
 
         ok = RSA_sign(nid, digest, dlen, sig, &len, key->rsa);
-        memset(digest, 'd', sizeof(digest));
+        explicit_bzero(digest, sizeof(digest));
 
         if (ok != 1) {
                 int ecode = ERR_get_error();
@@ -84,7 +84,7 @@ ssh_rsa_sign(const Key *key, u_char **sigp, u_int *lenp,
                 u_int diff = slen - len;
                 debug("slen %u > len %u", slen, len);
                 memmove(sig + diff, sig, len);
-                memset(sig, 0, diff);
+                explicit_bzero(sig, diff);
         } else if (len > slen) {
                 error("%s: slen %u slen2 %u", __func__, slen, len);
                 free(sig);
@@ -102,7 +102,7 @@ ssh_rsa_sign(const Key *key, u_char **sigp, u_int *lenp,
                 memcpy(*sigp, buffer_ptr(&b), len);
         }
         buffer_free(&b);
-        memset(sig, 's', slen);
+        explicit_bzero(sig, slen);
         free(sig);
 
         return 0;
@@ -161,7 +161,7 @@ ssh_rsa_verify(const Key *key, const u_char *signature, u_int signaturelen,
                     modlen, len);
                 sigblob = xrealloc(sigblob, 1, modlen);
                 memmove(sigblob + diff, sigblob, len);
-                memset(sigblob, 0, diff);
+                explicit_bzero(sigblob, diff);
                 len = modlen;
         }
         /* hash the data */
@@ -178,8 +178,8 @@ ssh_rsa_verify(const Key *key, const u_char *signature, u_int signaturelen,
 
         ret = openssh_RSA_verify(hash_alg, digest, dlen, sigblob, len,
             key->rsa);
-        memset(digest, 'd', sizeof(digest));
-        memset(sigblob, 's', len);
+        explicit_bzero(digest, sizeof(digest));
+        explicit_bzero(sigblob, len);
         free(sigblob);
         debug("%s: signature %scorrect", __func__, (ret == 0) ? "in" : "");
         return ret;
diff --git a/sshconnect.c b/sshconnect.c
index d21781ea4..3781eaf3b 100644
--- a/sshconnect.c
+++ b/sshconnect.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshconnect.c,v 1.244 2014/01/09 23:26:48 djm Exp $ */
+/* $OpenBSD: sshconnect.c,v 1.245 2014/02/02 03:44:31 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -1299,7 +1299,7 @@ ssh_put_password(char *password)
         padded = xcalloc(1, size);
         strlcpy(padded, password, size);
         packet_put_string(padded, size);
-        memset(padded, 0, size);
+        explicit_bzero(padded, size);
         free(padded);
 }
 
diff --git a/sshconnect1.c b/sshconnect1.c
index 57713d24d..921408ec1 100644
--- a/sshconnect1.c
+++ b/sshconnect1.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshconnect1.c,v 1.73 2014/01/27 19:18:54 markus Exp $ */
+/* $OpenBSD: sshconnect1.c,v 1.74 2014/02/02 03:44:32 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -120,7 +120,7 @@ try_agent_authentication(void)
                          * return a wrong value.
                          */
                         logit("Authentication agent failed to decrypt challenge.");
-                        memset(response, 0, sizeof(response));
+                        explicit_bzero(response, sizeof(response));
                 }
                 key_free(key);
                 debug("Sending response to RSA challenge.");
@@ -195,9 +195,9 @@ respond_to_rsa_challenge(BIGNUM * challenge, RSA * prv)
         packet_send();
         packet_write_wait();
 
-        memset(buf, 0, sizeof(buf));
-        memset(response, 0, sizeof(response));
-        memset(&md, 0, sizeof(md));
+        explicit_bzero(buf, sizeof(buf));
+        explicit_bzero(response, sizeof(response));
+        explicit_bzero(&md, sizeof(md));
 }
 
 /*
@@ -271,7 +271,7 @@ try_rsa_authentication(int idx)
                                 debug2("no passphrase given, try next key");
                                 quit = 1;
                         }
-                        memset(passphrase, 0, strlen(passphrase));
+                        explicit_bzero(passphrase, strlen(passphrase));
                         free(passphrase);
                         if (private != NULL || quit)
                                 break;
@@ -427,7 +427,7 @@ try_challenge_response_authentication(void)
                 }
                 packet_start(SSH_CMSG_AUTH_TIS_RESPONSE);
                 ssh_put_password(response);
-                memset(response, 0, strlen(response));
+                explicit_bzero(response, strlen(response));
                 free(response);
                 packet_send();
                 packet_write_wait();
@@ -460,7 +460,7 @@ try_password_authentication(char *prompt)
                 password = read_passphrase(prompt, 0);
                 packet_start(SSH_CMSG_AUTH_PASSWORD);
                 ssh_put_password(password);
-                memset(password, 0, strlen(password));
+                explicit_bzero(password, strlen(password));
                 free(password);
                 packet_send();
                 packet_write_wait();
@@ -652,8 +652,11 @@ ssh_kex(char *host, struct sockaddr *hostaddr)
         /* Set the encryption key. */
         packet_set_encryption_key(session_key, SSH_SESSION_KEY_LENGTH, options.cipher);
 
-        /* We will no longer need the session key here.  Destroy any extra copies. */
-        memset(session_key, 0, sizeof(session_key));
+        /*
+         * We will no longer need the session key here.
+         * Destroy any extra copies.
+         */
+        explicit_bzero(session_key, sizeof(session_key));
 
         /*
          * Expect a success message from the server.  Note that this message
diff --git a/sshconnect2.c b/sshconnect2.c
index c60a8511b..7f4ff4189 100644
--- a/sshconnect2.c
+++ b/sshconnect2.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshconnect2.c,v 1.203 2014/01/31 16:39:19 tedu Exp $ */
+/* $OpenBSD: sshconnect2.c,v 1.204 2014/02/02 03:44:32 djm Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  * Copyright (c) 2008 Damien Miller.  All rights reserved.
@@ -869,7 +869,7 @@ userauth_passwd(Authctxt *authctxt)
         packet_put_cstring(authctxt->method->name);
         packet_put_char(0);
         packet_put_cstring(password);
-        memset(password, 0, strlen(password));
+        explicit_bzero(password, strlen(password));
         free(password);
         packet_add_padding(64);
         packet_send();
@@ -915,7 +915,7 @@ input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt)
             authctxt->server_user, host);
         password = read_passphrase(prompt, 0);
         packet_put_cstring(password);
-        memset(password, 0, strlen(password));
+        explicit_bzero(password, strlen(password));
         free(password);
         password = NULL;
         while (password == NULL) {
@@ -932,16 +932,16 @@ input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt)
                     authctxt->server_user, host);
                 retype = read_passphrase(prompt, 0);
                 if (strcmp(password, retype) != 0) {
-                        memset(password, 0, strlen(password));
+                        explicit_bzero(password, strlen(password));
                         free(password);
                         logit("Mismatch; try again, EOF to quit.");
                         password = NULL;
                 }
-                memset(retype, 0, strlen(retype));
+                explicit_bzero(retype, strlen(retype));
                 free(retype);
         }
         packet_put_cstring(password);
-        memset(password, 0, strlen(password));
+        explicit_bzero(password, strlen(password));
         free(password);
         packet_add_padding(64);
         packet_send();
@@ -1126,7 +1126,7 @@ load_identity_file(char *filename, int userprovided)
                                 debug2("no passphrase given, try next key");
                                 quit = 1;
                         }
-                        memset(passphrase, 0, strlen(passphrase));
+                        explicit_bzero(passphrase, strlen(passphrase));
                         free(passphrase);
                         if (private != NULL || quit)
                                 break;
@@ -1385,7 +1385,7 @@ input_userauth_info_req(int type, u_int32_t seq, void *ctxt)
                 response = read_passphrase(prompt, echo ? RP_ECHO : 0);
 
                 packet_put_cstring(response);
-                memset(response, 0, strlen(response));
+                explicit_bzero(response, strlen(response));
                 free(response);
                 free(prompt);
         }
@@ -1555,7 +1555,7 @@ userauth_hostbased(Authctxt *authctxt)
         packet_put_cstring(chost);
         packet_put_cstring(authctxt->local_user);
         packet_put_string(signature, slen);
-        memset(signature, 's', slen);
+        explicit_bzero(signature, slen);
         free(signature);
         free(chost);
         free(pkalg);
diff --git a/sshd.c b/sshd.c
index b7411fe83..93e698b5d 100644
--- a/sshd.c
+++ b/sshd.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshd.c,v 1.417 2014/01/31 16:39:19 tedu Exp $ */
+/* $OpenBSD: sshd.c,v 1.418 2014/02/02 03:44:32 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -579,7 +579,7 @@ destroy_sensitive_data(void)
                 }
         }
         sensitive_data.ssh1_host_key = NULL;
-        memset(sensitive_data.ssh1_cookie, 0, SSH_SESSION_KEY_LENGTH);
+        explicit_bzero(sensitive_data.ssh1_cookie, SSH_SESSION_KEY_LENGTH);
 }
 
 /* Demote private to public keys for network child */
@@ -1657,7 +1657,8 @@ main(int ac, char **av)
                         fatal("Privilege separation user %s does not exist",
                             SSH_PRIVSEP_USER);
         } else {
-                memset(privsep_pw->pw_passwd, 0, strlen(privsep_pw->pw_passwd));
+                explicit_bzero(privsep_pw->pw_passwd,
+                    strlen(privsep_pw->pw_passwd));
                 privsep_pw = pwcopy(privsep_pw);
                 free(privsep_pw->pw_passwd);
                 privsep_pw->pw_passwd = xstrdup("*");
@@ -2341,7 +2342,7 @@ do_ssh1_kex(void)
                             get_remote_ipaddr(), len, (u_long)sizeof(session_key));
                         rsafail++;
                 } else {
-                        memset(session_key, 0, sizeof(session_key));
+                        explicit_bzero(session_key, sizeof(session_key));
                         BN_bn2bin(session_key_int,
                             session_key + sizeof(session_key) - len);
 
@@ -2379,7 +2380,7 @@ do_ssh1_kex(void)
                     sizeof(session_key) - 16) < 0)
                         fatal("%s: md5 failed", __func__);
                 ssh_digest_free(md);
-                memset(buf, 0, bytes);
+                explicit_bzero(buf, bytes);
                 free(buf);
                 for (i = 0; i < 16; i++)
                         session_id[i] = session_key[i] ^ session_key[i + 16];
@@ -2397,7 +2398,7 @@ do_ssh1_kex(void)
         packet_set_encryption_key(session_key, SSH_SESSION_KEY_LENGTH, cipher_type);
 
         /* Destroy our copy of the session key.  It is no longer needed. */
-        memset(session_key, 0, sizeof(session_key));
+        explicit_bzero(session_key, sizeof(session_key));
 
         debug("Received session key; encryption turned on.");