Add support for automatic DH ephemeral keys.

This allows an SSL server to enable DHE ciphers with a single setting,
which results in an DH key being generated based on the server key length.

Partly based on OpenSSL.

12 files changed, 194 insertions, 44 deletions

diff --git a/src/lib/libssl/s3_lib.c b/src/lib/libssl/s3_lib.c
index 08c5111129..21f1367442 100644
--- a/src/lib/libssl/s3_lib.c
+++ b/src/lib/libssl/s3_lib.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: s3_lib.c,v 1.83 2014/10/31 14:51:01 jsing Exp $ */
+/* $OpenBSD: s3_lib.c,v 1.84 2014/10/31 15:25:55 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -1994,13 +1994,15 @@ ssl3_ctrl(SSL *s, int cmd, long larg, void *parg)
                         ret = 1;
                 }
                 break;
+
         case SSL_CTRL_SET_TMP_DH_CB:
-                {
-                        SSLerr(SSL_F_SSL3_CTRL,
-                            ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
-                        return (ret);
-                }
-                break;
+                SSLerr(SSL_F_SSL3_CTRL, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
+                return (ret);
+
+        case SSL_CTRL_SET_DH_AUTO:
+                s->cert->dh_tmp_auto = larg;
+                return 1;
+
         case SSL_CTRL_SET_TMP_ECDH:
                 {
                         EC_KEY *ecdh = NULL;
@@ -2183,13 +2185,15 @@ ssl3_ctx_ctrl(SSL_CTX *ctx, int cmd, long larg, void *parg)
                         return 1;
                 }
                 /*break; */
+
         case SSL_CTRL_SET_TMP_DH_CB:
-                {
-                        SSLerr(SSL_F_SSL3_CTX_CTRL,
-                            ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
-                        return (0);
-                }
-                break;
+                SSLerr(SSL_F_SSL3_CTX_CTRL, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
+                return (0);
+
+        case SSL_CTRL_SET_DH_AUTO:
+                ctx->cert->dh_tmp_auto = larg;
+                return (1);
+
         case SSL_CTRL_SET_TMP_ECDH:
                 {
                         EC_KEY *ecdh = NULL;
diff --git a/src/lib/libssl/s3_srvr.c b/src/lib/libssl/s3_srvr.c
index 1b97895f76..3a311fbfb6 100644
--- a/src/lib/libssl/s3_srvr.c
+++ b/src/lib/libssl/s3_srvr.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: s3_srvr.c,v 1.88 2014/10/31 14:51:01 jsing Exp $ */
+/* $OpenBSD: s3_srvr.c,v 1.89 2014/10/31 15:25:55 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -1360,10 +1360,21 @@ ssl3_send_server_key_exchange(SSL *s)
                 r[0] = r[1] = r[2] = r[3] = NULL;
                 n = 0;
                 if (type & SSL_kDHE) {
-                        dhp = cert->dh_tmp;
-                        if ((dhp == NULL) && (s->cert->dh_tmp_cb != NULL))
+                        if (s->cert->dh_tmp_auto != 0) {
+                                if ((dhp = ssl_get_auto_dh(s)) == NULL) {
+                                        al = SSL_AD_INTERNAL_ERROR;
+                                        SSLerr(
+                                            SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,
+                                            ERR_R_INTERNAL_ERROR);
+                                        goto f_err;
+                                }
+                        } else
+                                dhp = cert->dh_tmp;
+
+                        if (dhp == NULL && s->cert->dh_tmp_cb != NULL)
                                 dhp = s->cert->dh_tmp_cb(s, 0,
                                     SSL_C_PKEYLENGTH(s->s3->tmp.new_cipher));
+
                         if (dhp == NULL) {
                                 al = SSL_AD_HANDSHAKE_FAILURE;
                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,
@@ -1377,7 +1388,9 @@ ssl3_send_server_key_exchange(SSL *s)
                                 goto err;
                         }
 
-                        if ((dh = DHparams_dup(dhp)) == NULL) {
+                        if (s->cert->dh_tmp_auto != 0) {
+                                dh = dhp;
+                        } else if ((dh = DHparams_dup(dhp)) == NULL) {
                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,
                                     ERR_R_DH_LIB);
                                 goto err;
diff --git a/src/lib/libssl/src/ssl/s3_lib.c b/src/lib/libssl/src/ssl/s3_lib.c
index 08c5111129..21f1367442 100644
--- a/src/lib/libssl/src/ssl/s3_lib.c
+++ b/src/lib/libssl/src/ssl/s3_lib.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: s3_lib.c,v 1.83 2014/10/31 14:51:01 jsing Exp $ */
+/* $OpenBSD: s3_lib.c,v 1.84 2014/10/31 15:25:55 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -1994,13 +1994,15 @@ ssl3_ctrl(SSL *s, int cmd, long larg, void *parg)
                         ret = 1;
                 }
                 break;
+
         case SSL_CTRL_SET_TMP_DH_CB:
-                {
-                        SSLerr(SSL_F_SSL3_CTRL,
-                            ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
-                        return (ret);
-                }
-                break;
+                SSLerr(SSL_F_SSL3_CTRL, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
+                return (ret);
+
+        case SSL_CTRL_SET_DH_AUTO:
+                s->cert->dh_tmp_auto = larg;
+                return 1;
+
         case SSL_CTRL_SET_TMP_ECDH:
                 {
                         EC_KEY *ecdh = NULL;
@@ -2183,13 +2185,15 @@ ssl3_ctx_ctrl(SSL_CTX *ctx, int cmd, long larg, void *parg)
                         return 1;
                 }
                 /*break; */
+
         case SSL_CTRL_SET_TMP_DH_CB:
-                {
-                        SSLerr(SSL_F_SSL3_CTX_CTRL,
-                            ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
-                        return (0);
-                }
-                break;
+                SSLerr(SSL_F_SSL3_CTX_CTRL, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
+                return (0);
+
+        case SSL_CTRL_SET_DH_AUTO:
+                ctx->cert->dh_tmp_auto = larg;
+                return (1);
+
         case SSL_CTRL_SET_TMP_ECDH:
                 {
                         EC_KEY *ecdh = NULL;
diff --git a/src/lib/libssl/src/ssl/s3_srvr.c b/src/lib/libssl/src/ssl/s3_srvr.c
index 1b97895f76..3a311fbfb6 100644
--- a/src/lib/libssl/src/ssl/s3_srvr.c
+++ b/src/lib/libssl/src/ssl/s3_srvr.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: s3_srvr.c,v 1.88 2014/10/31 14:51:01 jsing Exp $ */
+/* $OpenBSD: s3_srvr.c,v 1.89 2014/10/31 15:25:55 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -1360,10 +1360,21 @@ ssl3_send_server_key_exchange(SSL *s)
                 r[0] = r[1] = r[2] = r[3] = NULL;
                 n = 0;
                 if (type & SSL_kDHE) {
-                        dhp = cert->dh_tmp;
-                        if ((dhp == NULL) && (s->cert->dh_tmp_cb != NULL))
+                        if (s->cert->dh_tmp_auto != 0) {
+                                if ((dhp = ssl_get_auto_dh(s)) == NULL) {
+                                        al = SSL_AD_INTERNAL_ERROR;
+                                        SSLerr(
+                                            SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,
+                                            ERR_R_INTERNAL_ERROR);
+                                        goto f_err;
+                                }
+                        } else
+                                dhp = cert->dh_tmp;
+
+                        if (dhp == NULL && s->cert->dh_tmp_cb != NULL)
                                 dhp = s->cert->dh_tmp_cb(s, 0,
                                     SSL_C_PKEYLENGTH(s->s3->tmp.new_cipher));
+
                         if (dhp == NULL) {
                                 al = SSL_AD_HANDSHAKE_FAILURE;
                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,
@@ -1377,7 +1388,9 @@ ssl3_send_server_key_exchange(SSL *s)
                                 goto err;
                         }
 
-                        if ((dh = DHparams_dup(dhp)) == NULL) {
+                        if (s->cert->dh_tmp_auto != 0) {
+                                dh = dhp;
+                        } else if ((dh = DHparams_dup(dhp)) == NULL) {
                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,
                                     ERR_R_DH_LIB);
                                 goto err;
diff --git a/src/lib/libssl/src/ssl/ssl.h b/src/lib/libssl/src/ssl/ssl.h
index 2b1ceaf2c7..350d6fb4d1 100644
--- a/src/lib/libssl/src/ssl/ssl.h
+++ b/src/lib/libssl/src/ssl/ssl.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl.h,v 1.68 2014/10/15 13:57:21 jsing Exp $ */
+/* $OpenBSD: ssl.h,v 1.69 2014/10/31 15:25:55 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -1429,6 +1429,8 @@ DECLARE_PEM_rw(SSL_SESSION, SSL_SESSION)
 
 #define SSL_CTRL_SET_ECDH_AUTO                          94
 
+#define SSL_CTRL_SET_DH_AUTO                    118
+
 #define DTLSv1_get_timeout(ssl, arg) \
         SSL_ctrl(ssl,DTLS_CTRL_GET_TIMEOUT,0, (void *)arg)
 #define DTLSv1_handle_timeout(ssl) \
@@ -1453,6 +1455,8 @@ DECLARE_PEM_rw(SSL_SESSION, SSL_SESSION)
         SSL_CTX_ctrl(ctx,SSL_CTRL_SET_TMP_DH,0,(char *)dh)
 #define SSL_CTX_set_tmp_ecdh(ctx,ecdh) \
         SSL_CTX_ctrl(ctx,SSL_CTRL_SET_TMP_ECDH,0,(char *)ecdh)
+#define SSL_CTX_set_dh_auto(ctx, onoff) \
+        SSL_CTX_ctrl(ctx,SSL_CTRL_SET_DH_AUTO,onoff,NULL)
 #define SSL_CTX_set_ecdh_auto(ctx, onoff) \
         SSL_CTX_ctrl(ctx,SSL_CTRL_SET_ECDH_AUTO,onoff,NULL)
 
@@ -1464,6 +1468,8 @@ DECLARE_PEM_rw(SSL_SESSION, SSL_SESSION)
         SSL_ctrl(ssl,SSL_CTRL_SET_TMP_DH,0,(char *)dh)
 #define SSL_set_tmp_ecdh(ssl,ecdh) \
         SSL_ctrl(ssl,SSL_CTRL_SET_TMP_ECDH,0,(char *)ecdh)
+#define SSL_set_dh_auto(s, onoff) \
+        SSL_ctrl(s,SSL_CTRL_SET_DH_AUTO,onoff,NULL)
 #define SSL_set_ecdh_auto(s, onoff) \
         SSL_ctrl(s,SSL_CTRL_SET_ECDH_AUTO,onoff,NULL)
 
diff --git a/src/lib/libssl/src/ssl/ssl_cert.c b/src/lib/libssl/src/ssl/ssl_cert.c
index beea31c64b..8adb9aa032 100644
--- a/src/lib/libssl/src/ssl/ssl_cert.c
+++ b/src/lib/libssl/src/ssl/ssl_cert.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_cert.c,v 1.43 2014/10/31 14:51:01 jsing Exp $ */
+/* $OpenBSD: ssl_cert.c,v 1.44 2014/10/31 15:25:55 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -229,6 +229,7 @@ ssl_cert_dup(CERT *cert)
                 }
         }
         ret->dh_tmp_cb = cert->dh_tmp_cb;
+        ret->dh_tmp_auto = cert->dh_tmp_auto;
 
         if (cert->ecdh_tmp) {
                 ret->ecdh_tmp = EC_KEY_dup(cert->ecdh_tmp);
diff --git a/src/lib/libssl/src/ssl/ssl_lib.c b/src/lib/libssl/src/ssl/ssl_lib.c
index 579c005cc3..078a710c33 100644
--- a/src/lib/libssl/src/ssl/ssl_lib.c
+++ b/src/lib/libssl/src/ssl/ssl_lib.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_lib.c,v 1.88 2014/10/31 14:51:01 jsing Exp $ */
+/* $OpenBSD: ssl_lib.c,v 1.89 2014/10/31 15:25:55 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -1942,7 +1942,8 @@ ssl_set_cert_masks(CERT *c, const SSL_CIPHER *cipher)
         if (c == NULL)
                 return;
 
-        dh_tmp = (c->dh_tmp != NULL || c->dh_tmp_cb != NULL);
+        dh_tmp = (c->dh_tmp != NULL || c->dh_tmp_cb != NULL ||
+            c->dh_tmp_auto != 0);
 
         have_ecdh_tmp = (c->ecdh_tmp != NULL || c->ecdh_tmp_cb != NULL ||
             c->ecdh_tmp_auto != 0);
@@ -2176,6 +2177,54 @@ ssl_get_sign_pkey(SSL *s, const SSL_CIPHER *cipher, const EVP_MD **pmd)
         return (c->pkeys[idx].privatekey);
 }
 
+DH *
+ssl_get_auto_dh(SSL *s)
+{
+        CERT_PKEY *cpk;
+        int keylen;
+        DH *dhp;
+
+        if (s->cert->dh_tmp_auto == 2) {
+                keylen = 1024;
+        } else if (s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) {
+                keylen = 1024;
+                if (s->s3->tmp.new_cipher->strength_bits == 256)
+                        keylen = 3072;
+        } else {
+                if ((cpk = ssl_get_server_send_pkey(s)) == NULL)
+                        return (NULL);
+                if (cpk->privatekey == NULL || cpk->privatekey->pkey.dh == NULL)
+                        return (NULL);
+                keylen = EVP_PKEY_bits(cpk->privatekey);
+        }
+
+        if ((dhp = DH_new()) == NULL)
+                return (NULL);
+
+        dhp->g = BN_new();
+        if (dhp->g != NULL)
+                BN_set_word(dhp->g, 2);
+
+        if (keylen >= 8192)
+                dhp->p = get_rfc3526_prime_8192(NULL);
+        else if (keylen >= 4096)
+                dhp->p = get_rfc3526_prime_4096(NULL);
+        else if (keylen >= 3072)
+                dhp->p = get_rfc3526_prime_3072(NULL);
+        else if (keylen >= 2048)
+                dhp->p = get_rfc3526_prime_2048(NULL);
+        else if (keylen >= 1536)
+                dhp->p = get_rfc3526_prime_1536(NULL);
+        else
+                dhp->p = get_rfc2409_prime_1024(NULL);
+
+        if (dhp->p == NULL || dhp->g == NULL) {
+                DH_free(dhp);
+                return (NULL);
+        }
+        return (dhp);
+}
+
 void
 ssl_update_cache(SSL *s, int mode)
 {
diff --git a/src/lib/libssl/src/ssl/ssl_locl.h b/src/lib/libssl/src/ssl/ssl_locl.h
index 955c169244..e7bcb890e4 100644
--- a/src/lib/libssl/src/ssl/ssl_locl.h
+++ b/src/lib/libssl/src/ssl/ssl_locl.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_locl.h,v 1.72 2014/10/31 14:51:01 jsing Exp $ */
+/* $OpenBSD: ssl_locl.h,v 1.73 2014/10/31 15:25:55 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -442,6 +442,7 @@ typedef struct cert_st {
 
         DH *dh_tmp;
         DH *(*dh_tmp_cb)(SSL *ssl, int is_export, int keysize);
+        int dh_tmp_auto;
 
         EC_KEY *ecdh_tmp;
         EC_KEY *(*ecdh_tmp_cb)(SSL *ssl, int is_export, int keysize);
@@ -588,6 +589,7 @@ int ssl_undefined_const_function(const SSL *s);
 CERT_PKEY *ssl_get_server_send_pkey(const SSL *s);
 X509 *ssl_get_server_send_cert(const SSL *);
 EVP_PKEY *ssl_get_sign_pkey(SSL *s, const SSL_CIPHER *c, const EVP_MD **pmd);
+DH *ssl_get_auto_dh(SSL *s);
 int ssl_cert_type(X509 *x, EVP_PKEY *pkey);
 void ssl_set_cert_masks(CERT *c, const SSL_CIPHER *cipher);
 STACK_OF(SSL_CIPHER) *ssl_get_ciphers_by_id(SSL *s);
diff --git a/src/lib/libssl/ssl.h b/src/lib/libssl/ssl.h
index 2b1ceaf2c7..350d6fb4d1 100644
--- a/src/lib/libssl/ssl.h
+++ b/src/lib/libssl/ssl.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl.h,v 1.68 2014/10/15 13:57:21 jsing Exp $ */
+/* $OpenBSD: ssl.h,v 1.69 2014/10/31 15:25:55 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -1429,6 +1429,8 @@ DECLARE_PEM_rw(SSL_SESSION, SSL_SESSION)
 
 #define SSL_CTRL_SET_ECDH_AUTO                          94
 
+#define SSL_CTRL_SET_DH_AUTO                    118
+
 #define DTLSv1_get_timeout(ssl, arg) \
         SSL_ctrl(ssl,DTLS_CTRL_GET_TIMEOUT,0, (void *)arg)
 #define DTLSv1_handle_timeout(ssl) \
@@ -1453,6 +1455,8 @@ DECLARE_PEM_rw(SSL_SESSION, SSL_SESSION)
         SSL_CTX_ctrl(ctx,SSL_CTRL_SET_TMP_DH,0,(char *)dh)
 #define SSL_CTX_set_tmp_ecdh(ctx,ecdh) \
         SSL_CTX_ctrl(ctx,SSL_CTRL_SET_TMP_ECDH,0,(char *)ecdh)
+#define SSL_CTX_set_dh_auto(ctx, onoff) \
+        SSL_CTX_ctrl(ctx,SSL_CTRL_SET_DH_AUTO,onoff,NULL)
 #define SSL_CTX_set_ecdh_auto(ctx, onoff) \
         SSL_CTX_ctrl(ctx,SSL_CTRL_SET_ECDH_AUTO,onoff,NULL)
 
@@ -1464,6 +1468,8 @@ DECLARE_PEM_rw(SSL_SESSION, SSL_SESSION)
         SSL_ctrl(ssl,SSL_CTRL_SET_TMP_DH,0,(char *)dh)
 #define SSL_set_tmp_ecdh(ssl,ecdh) \
         SSL_ctrl(ssl,SSL_CTRL_SET_TMP_ECDH,0,(char *)ecdh)
+#define SSL_set_dh_auto(s, onoff) \
+        SSL_ctrl(s,SSL_CTRL_SET_DH_AUTO,onoff,NULL)
 #define SSL_set_ecdh_auto(s, onoff) \
         SSL_ctrl(s,SSL_CTRL_SET_ECDH_AUTO,onoff,NULL)
 
diff --git a/src/lib/libssl/ssl_cert.c b/src/lib/libssl/ssl_cert.c
index beea31c64b..8adb9aa032 100644
--- a/src/lib/libssl/ssl_cert.c
+++ b/src/lib/libssl/ssl_cert.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_cert.c,v 1.43 2014/10/31 14:51:01 jsing Exp $ */
+/* $OpenBSD: ssl_cert.c,v 1.44 2014/10/31 15:25:55 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -229,6 +229,7 @@ ssl_cert_dup(CERT *cert)
                 }
         }
         ret->dh_tmp_cb = cert->dh_tmp_cb;
+        ret->dh_tmp_auto = cert->dh_tmp_auto;
 
         if (cert->ecdh_tmp) {
                 ret->ecdh_tmp = EC_KEY_dup(cert->ecdh_tmp);
diff --git a/src/lib/libssl/ssl_lib.c b/src/lib/libssl/ssl_lib.c
index 579c005cc3..078a710c33 100644
--- a/src/lib/libssl/ssl_lib.c
+++ b/src/lib/libssl/ssl_lib.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_lib.c,v 1.88 2014/10/31 14:51:01 jsing Exp $ */
+/* $OpenBSD: ssl_lib.c,v 1.89 2014/10/31 15:25:55 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -1942,7 +1942,8 @@ ssl_set_cert_masks(CERT *c, const SSL_CIPHER *cipher)
         if (c == NULL)
                 return;
 
-        dh_tmp = (c->dh_tmp != NULL || c->dh_tmp_cb != NULL);
+        dh_tmp = (c->dh_tmp != NULL || c->dh_tmp_cb != NULL ||
+            c->dh_tmp_auto != 0);
 
         have_ecdh_tmp = (c->ecdh_tmp != NULL || c->ecdh_tmp_cb != NULL ||
             c->ecdh_tmp_auto != 0);
@@ -2176,6 +2177,54 @@ ssl_get_sign_pkey(SSL *s, const SSL_CIPHER *cipher, const EVP_MD **pmd)
         return (c->pkeys[idx].privatekey);
 }
 
+DH *
+ssl_get_auto_dh(SSL *s)
+{
+        CERT_PKEY *cpk;
+        int keylen;
+        DH *dhp;
+
+        if (s->cert->dh_tmp_auto == 2) {
+                keylen = 1024;
+        } else if (s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) {
+                keylen = 1024;
+                if (s->s3->tmp.new_cipher->strength_bits == 256)
+                        keylen = 3072;
+        } else {
+                if ((cpk = ssl_get_server_send_pkey(s)) == NULL)
+                        return (NULL);
+                if (cpk->privatekey == NULL || cpk->privatekey->pkey.dh == NULL)
+                        return (NULL);
+                keylen = EVP_PKEY_bits(cpk->privatekey);
+        }
+
+        if ((dhp = DH_new()) == NULL)
+                return (NULL);
+
+        dhp->g = BN_new();
+        if (dhp->g != NULL)
+                BN_set_word(dhp->g, 2);
+
+        if (keylen >= 8192)
+                dhp->p = get_rfc3526_prime_8192(NULL);
+        else if (keylen >= 4096)
+                dhp->p = get_rfc3526_prime_4096(NULL);
+        else if (keylen >= 3072)
+                dhp->p = get_rfc3526_prime_3072(NULL);
+        else if (keylen >= 2048)
+                dhp->p = get_rfc3526_prime_2048(NULL);
+        else if (keylen >= 1536)
+                dhp->p = get_rfc3526_prime_1536(NULL);
+        else
+                dhp->p = get_rfc2409_prime_1024(NULL);
+
+        if (dhp->p == NULL || dhp->g == NULL) {
+                DH_free(dhp);
+                return (NULL);
+        }
+        return (dhp);
+}
+
 void
 ssl_update_cache(SSL *s, int mode)
 {
diff --git a/src/lib/libssl/ssl_locl.h b/src/lib/libssl/ssl_locl.h
index 955c169244..e7bcb890e4 100644
--- a/src/lib/libssl/ssl_locl.h
+++ b/src/lib/libssl/ssl_locl.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_locl.h,v 1.72 2014/10/31 14:51:01 jsing Exp $ */
+/* $OpenBSD: ssl_locl.h,v 1.73 2014/10/31 15:25:55 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -442,6 +442,7 @@ typedef struct cert_st {
 
         DH *dh_tmp;
         DH *(*dh_tmp_cb)(SSL *ssl, int is_export, int keysize);
+        int dh_tmp_auto;
 
         EC_KEY *ecdh_tmp;
         EC_KEY *(*ecdh_tmp_cb)(SSL *ssl, int is_export, int keysize);
@@ -588,6 +589,7 @@ int ssl_undefined_const_function(const SSL *s);
 CERT_PKEY *ssl_get_server_send_pkey(const SSL *s);
 X509 *ssl_get_server_send_cert(const SSL *);
 EVP_PKEY *ssl_get_sign_pkey(SSL *s, const SSL_CIPHER *c, const EVP_MD **pmd);
+DH *ssl_get_auto_dh(SSL *s);
 int ssl_cert_type(X509 *x, EVP_PKEY *pkey);
 void ssl_set_cert_masks(CERT *c, const SSL_CIPHER *cipher);
 STACK_OF(SSL_CIPHER) *ssl_get_ciphers_by_id(SSL *s);