Move extension data into sub-structs

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2052)

12 files changed, 628 insertions, 594 deletions

diff --git a/ssl/s3_lib.c b/ssl/s3_lib.c
index 524f5308f3..0f6e94844a 100644
--- a/ssl/s3_lib.c
+++ b/ssl/s3_lib.c
@@ -2882,9 +2882,9 @@ void ssl3_clear(SSL *s)
     s->version = SSL3_VERSION;
 
 #if !defined(OPENSSL_NO_NEXTPROTONEG)
-    OPENSSL_free(s->next_proto_negotiated);
-    s->next_proto_negotiated = NULL;
-    s->next_proto_negotiated_len = 0;
+    OPENSSL_free(s->ext.npn);
+    s->ext.npn = NULL;
+    s->ext.npn_len = 0;
 #endif
 }
 
@@ -2969,8 +2969,8 @@ long ssl3_ctrl(SSL *s, int cmd, long larg, void *parg)
             nid = EC_GROUP_get_curve_name(group);
             if (nid == NID_undef)
                 return 0;
-            return tls1_set_groups(&s->tlsext_supportedgroupslist,
-                                   &s->tlsext_supportedgroupslist_length,
+            return tls1_set_groups(&s->ext.supportedgroups,
+                                   &s->ext.supportedgroups_len,
                                    &nid, 1);
         }
         break;
@@ -2979,8 +2979,8 @@ long ssl3_ctrl(SSL *s, int cmd, long larg, void *parg)
         if (larg == TLSEXT_NAMETYPE_host_name) {
             size_t len;
 
-            OPENSSL_free(s->tlsext_hostname);
-            s->tlsext_hostname = NULL;
+            OPENSSL_free(s->ext.hostname);
+            s->ext.hostname = NULL;
 
             ret = 1;
             if (parg == NULL)
@@ -2990,7 +2990,7 @@ long ssl3_ctrl(SSL *s, int cmd, long larg, void *parg)
                 SSLerr(SSL_F_SSL3_CTRL, SSL_R_SSL3_EXT_INVALID_SERVERNAME);
                 return 0;
             }
-            if ((s->tlsext_hostname = OPENSSL_strdup((char *)parg)) == NULL) {
+            if ((s->ext.hostname = OPENSSL_strdup((char *)parg)) == NULL) {
                 SSLerr(SSL_F_SSL3_CTRL, ERR_R_INTERNAL_ERROR);
                 return 0;
             }
@@ -3000,50 +3000,50 @@ long ssl3_ctrl(SSL *s, int cmd, long larg, void *parg)
         }
         break;
     case SSL_CTRL_SET_TLSEXT_DEBUG_ARG:
-        s->tlsext_debug_arg = parg;
+        s->ext.debug_arg = parg;
         ret = 1;
         break;
 
     case SSL_CTRL_GET_TLSEXT_STATUS_REQ_TYPE:
-        ret = s->tlsext_status_type;
+        ret = s->ext.status_type;
         break;
 
     case SSL_CTRL_SET_TLSEXT_STATUS_REQ_TYPE:
-        s->tlsext_status_type = larg;
+        s->ext.status_type = larg;
         ret = 1;
         break;
 
     case SSL_CTRL_GET_TLSEXT_STATUS_REQ_EXTS:
-        *(STACK_OF(X509_EXTENSION) **)parg = s->tlsext_ocsp_exts;
+        *(STACK_OF(X509_EXTENSION) **)parg = s->ext.ocsp.exts;
         ret = 1;
         break;
 
     case SSL_CTRL_SET_TLSEXT_STATUS_REQ_EXTS:
-        s->tlsext_ocsp_exts = parg;
+        s->ext.ocsp.exts = parg;
         ret = 1;
         break;
 
     case SSL_CTRL_GET_TLSEXT_STATUS_REQ_IDS:
-        *(STACK_OF(OCSP_RESPID) **)parg = s->tlsext_ocsp_ids;
+        *(STACK_OF(OCSP_RESPID) **)parg = s->ext.ocsp.ids;
         ret = 1;
         break;
 
     case SSL_CTRL_SET_TLSEXT_STATUS_REQ_IDS:
-        s->tlsext_ocsp_ids = parg;
+        s->ext.ocsp.ids = parg;
         ret = 1;
         break;
 
     case SSL_CTRL_GET_TLSEXT_STATUS_REQ_OCSP_RESP:
-        *(unsigned char **)parg = s->tlsext_ocsp_resp;
-        if (s->tlsext_ocsp_resplen == 0
-                || s->tlsext_ocsp_resplen > LONG_MAX)
+        *(unsigned char **)parg = s->ext.ocsp.resp;
+        if (s->ext.ocsp.resp_len == 0
+                || s->ext.ocsp.resp_len > LONG_MAX)
             return -1;
-        return (long)s->tlsext_ocsp_resplen;
+        return (long)s->ext.ocsp.resp_len;
 
     case SSL_CTRL_SET_TLSEXT_STATUS_REQ_OCSP_RESP:
-        OPENSSL_free(s->tlsext_ocsp_resp);
-        s->tlsext_ocsp_resp = parg;
-        s->tlsext_ocsp_resplen = larg;
+        OPENSSL_free(s->ext.ocsp.resp);
+        s->ext.ocsp.resp = parg;
+        s->ext.ocsp.resp_len = larg;
         ret = 1;
         break;
 
@@ -3101,10 +3101,11 @@ long ssl3_ctrl(SSL *s, int cmd, long larg, void *parg)
         {
             unsigned char *clist;
             size_t clistlen;
+
             if (!s->session)
                 return 0;
-            clist = s->session->tlsext_supportedgroupslist;
-            clistlen = s->session->tlsext_supportedgroupslist_length / 2;
+            clist = s->session->ext.supportedgroups;
+            clistlen = s->session->ext.supportedgroups_len / 2;
             if (parg) {
                 size_t i;
                 int *cptr = parg;
@@ -3123,12 +3124,12 @@ long ssl3_ctrl(SSL *s, int cmd, long larg, void *parg)
         }
 
     case SSL_CTRL_SET_GROUPS:
-        return tls1_set_groups(&s->tlsext_supportedgroupslist,
-                               &s->tlsext_supportedgroupslist_length, parg, larg);
+        return tls1_set_groups(&s->ext.supportedgroups,
+                               &s->ext.supportedgroups_len, parg, larg);
 
     case SSL_CTRL_SET_GROUPS_LIST:
-        return tls1_set_groups_list(&s->tlsext_supportedgroupslist,
-                                    &s->tlsext_supportedgroupslist_length, parg);
+        return tls1_set_groups_list(&s->ext.supportedgroups,
+                                    &s->ext.supportedgroups_len, parg);
 
     case SSL_CTRL_GET_SHARED_GROUP:
         return tls1_shared_group(s, larg);
@@ -3208,10 +3209,11 @@ long ssl3_ctrl(SSL *s, int cmd, long larg, void *parg)
         {
             SSL_SESSION *sess = s->session;
             const unsigned char **pformat = parg;
-            if (!sess || !sess->tlsext_ecpointformatlist)
+
+            if (sess == NULL || sess->ext.ecpointformats == NULL)
                 return 0;
-            *pformat = sess->tlsext_ecpointformatlist;
-            return (int)sess->tlsext_ecpointformatlist_length;
+            *pformat = sess->ext.ecpointformats;
+            return (int)sess->ext.ecpointformats_len;
         }
 #endif
 
@@ -3234,7 +3236,7 @@ long ssl3_callback_ctrl(SSL *s, int cmd, void (*fp) (void))
         break;
 #endif
     case SSL_CTRL_SET_TLSEXT_DEBUG_CB:
-        s->tlsext_debug_cb = (void (*)(SSL *, int, int,
+        s->ext.debug_cb = (void (*)(SSL *, int, int,
                                        const unsigned char *, int, void *))fp;
         break;
 
@@ -3306,69 +3308,69 @@ long ssl3_ctx_ctrl(SSL_CTX *ctx, int cmd, long larg, void *parg)
             nid = EC_GROUP_get_curve_name(group);
             if (nid == NID_undef)
                 return 0;
-            return tls1_set_groups(&ctx->tlsext_supportedgroupslist,
-                                   &ctx->tlsext_supportedgroupslist_length,
+            return tls1_set_groups(&ctx->ext.supportedgroups,
+                                   &ctx->ext.supportedgroups_len,
                                    &nid, 1);
         }
         /* break; */
 #endif                          /* !OPENSSL_NO_EC */
     case SSL_CTRL_SET_TLSEXT_SERVERNAME_ARG:
-        ctx->tlsext_servername_arg = parg;
+        ctx->ext.servername_arg = parg;
         break;
     case SSL_CTRL_SET_TLSEXT_TICKET_KEYS:
     case SSL_CTRL_GET_TLSEXT_TICKET_KEYS:
         {
             unsigned char *keys = parg;
-            long tlsext_tick_keylen = (sizeof(ctx->tlsext_tick_key_name) +
-                                       sizeof(ctx->tlsext_tick_hmac_key) +
-                                       sizeof(ctx->tlsext_tick_aes_key));
+            long tick_keylen = (sizeof(ctx->ext.tick_key_name) +
+                                sizeof(ctx->ext.tick_hmac_key) +
+                                sizeof(ctx->ext.tick_aes_key));
             if (keys == NULL)
-                return tlsext_tick_keylen;
-            if (larg != tlsext_tick_keylen) {
+                return tick_keylen;
+            if (larg != tick_keylen) {
                 SSLerr(SSL_F_SSL3_CTX_CTRL, SSL_R_INVALID_TICKET_KEYS_LENGTH);
                 return 0;
             }
             if (cmd == SSL_CTRL_SET_TLSEXT_TICKET_KEYS) {
-                memcpy(ctx->tlsext_tick_key_name, keys,
-                       sizeof(ctx->tlsext_tick_key_name));
-                memcpy(ctx->tlsext_tick_hmac_key,
-                       keys + sizeof(ctx->tlsext_tick_key_name),
-                       sizeof(ctx->tlsext_tick_hmac_key));
-                memcpy(ctx->tlsext_tick_aes_key,
-                       keys + sizeof(ctx->tlsext_tick_key_name) +
-                       sizeof(ctx->tlsext_tick_hmac_key),
-                       sizeof(ctx->tlsext_tick_aes_key));
+                memcpy(ctx->ext.tick_key_name, keys,
+                       sizeof(ctx->ext.tick_key_name));
+                memcpy(ctx->ext.tick_hmac_key,
+                       keys + sizeof(ctx->ext.tick_key_name),
+                       sizeof(ctx->ext.tick_hmac_key));
+                memcpy(ctx->ext.tick_aes_key,
+                       keys + sizeof(ctx->ext.tick_key_name) +
+                       sizeof(ctx->ext.tick_hmac_key),
+                       sizeof(ctx->ext.tick_aes_key));
             } else {
-                memcpy(keys, ctx->tlsext_tick_key_name,
-                       sizeof(ctx->tlsext_tick_key_name));
-                memcpy(keys + sizeof(ctx->tlsext_tick_key_name),
-                       ctx->tlsext_tick_hmac_key,
-                       sizeof(ctx->tlsext_tick_hmac_key));
-                memcpy(keys + sizeof(ctx->tlsext_tick_key_name) +
-                       sizeof(ctx->tlsext_tick_hmac_key),
-                       ctx->tlsext_tick_aes_key,
-                       sizeof(ctx->tlsext_tick_aes_key));
+                memcpy(keys, ctx->ext.tick_key_name,
+                       sizeof(ctx->ext.tick_key_name));
+                memcpy(keys + sizeof(ctx->ext.tick_key_name),
+                       ctx->ext.tick_hmac_key,
+                       sizeof(ctx->ext.tick_hmac_key));
+                memcpy(keys + sizeof(ctx->ext.tick_key_name) +
+                       sizeof(ctx->ext.tick_hmac_key),
+                       ctx->ext.tick_aes_key,
+                       sizeof(ctx->ext.tick_aes_key));
             }
             return 1;
         }
 
     case SSL_CTRL_GET_TLSEXT_STATUS_REQ_TYPE:
-        return ctx->tlsext_status_type;
+        return ctx->ext.status_type;
 
     case SSL_CTRL_SET_TLSEXT_STATUS_REQ_TYPE:
-        ctx->tlsext_status_type = larg;
+        ctx->ext.status_type = larg;
         break;
 
     case SSL_CTRL_SET_TLSEXT_STATUS_REQ_CB_ARG:
-        ctx->tlsext_status_arg = parg;
+        ctx->ext.status_arg = parg;
         return 1;
 
     case SSL_CTRL_GET_TLSEXT_STATUS_REQ_CB_ARG:
-        *(void**)parg = ctx->tlsext_status_arg;
+        *(void**)parg = ctx->ext.status_arg;
         break;
 
     case SSL_CTRL_GET_TLSEXT_STATUS_REQ_CB:
-        *(int (**)(SSL*, void*))parg = ctx->tlsext_status_cb;
+        *(int (**)(SSL*, void*))parg = ctx->ext.status_cb;
         break;
 
 #ifndef OPENSSL_NO_SRP
@@ -3404,13 +3406,13 @@ long ssl3_ctx_ctrl(SSL_CTX *ctx, int cmd, long larg, void *parg)
 
 #ifndef OPENSSL_NO_EC
     case SSL_CTRL_SET_GROUPS:
-        return tls1_set_groups(&ctx->tlsext_supportedgroupslist,
-                               &ctx->tlsext_supportedgroupslist_length,
+        return tls1_set_groups(&ctx->ext.supportedgroups,
+                               &ctx->ext.supportedgroups_len,
                                parg, larg);
 
     case SSL_CTRL_SET_GROUPS_LIST:
-        return tls1_set_groups_list(&ctx->tlsext_supportedgroupslist,
-                                    &ctx->tlsext_supportedgroupslist_length,
+        return tls1_set_groups_list(&ctx->ext.supportedgroups,
+                                    &ctx->ext.supportedgroups_len,
                                     parg);
 #endif
     case SSL_CTRL_SET_SIGALGS:
@@ -3502,15 +3504,15 @@ long ssl3_ctx_callback_ctrl(SSL_CTX *ctx, int cmd, void (*fp) (void))
         break;
 #endif
     case SSL_CTRL_SET_TLSEXT_SERVERNAME_CB:
-        ctx->tlsext_servername_callback = (int (*)(SSL *, int *, void *))fp;
+        ctx->ext.servername_cb = (int (*)(SSL *, int *, void *))fp;
         break;
 
     case SSL_CTRL_SET_TLSEXT_STATUS_REQ_CB:
-        ctx->tlsext_status_cb = (int (*)(SSL *, void *))fp;
+        ctx->ext.status_cb = (int (*)(SSL *, void *))fp;
         break;
 
     case SSL_CTRL_SET_TLSEXT_TICKET_KEY_CB:
-        ctx->tlsext_ticket_key_cb = (int (*)(SSL *, unsigned char *,
+        ctx->ext.ticket_key_cb = (int (*)(SSL *, unsigned char *,
                                              unsigned char *,
                                              EVP_CIPHER_CTX *,
                                              HMAC_CTX *, int))fp;
diff --git a/ssl/ssl_asn1.c b/ssl/ssl_asn1.c
index fd13f90c28..401aeb5eaf 100644
--- a/ssl/ssl_asn1.c
+++ b/ssl/ssl_asn1.c
@@ -183,13 +183,13 @@ int i2d_SSL_SESSION(SSL_SESSION *in, unsigned char **pp)
     as.peer = in->peer;
 
     ssl_session_sinit(&as.tlsext_hostname, &tlsext_hostname,
-                      in->tlsext_hostname);
-    if (in->tlsext_tick) {
+                      in->ext.hostname);
+    if (in->ext.tick) {
         ssl_session_oinit(&as.tlsext_tick, &tlsext_tick,
-                          in->tlsext_tick, in->tlsext_ticklen);
+                          in->ext.tick, in->ext.ticklen);
     }
-    if (in->tlsext_tick_lifetime_hint > 0)
-        as.tlsext_tick_lifetime_hint = in->tlsext_tick_lifetime_hint;
+    if (in->ext.tick_lifetime_hint > 0)
+        as.tlsext_tick_lifetime_hint = in->ext.tick_lifetime_hint;
 #ifndef OPENSSL_NO_PSK
     ssl_session_sinit(&as.psk_identity_hint, &psk_identity_hint,
                       in->psk_identity_hint);
@@ -315,7 +315,7 @@ SSL_SESSION *d2i_SSL_SESSION(SSL_SESSION **a, const unsigned char **pp,
     /* NB: this defaults to zero which is X509_V_OK */
     ret->verify_result = as->verify_result;
 
-    if (!ssl_session_strndup(&ret->tlsext_hostname, as->tlsext_hostname))
+    if (!ssl_session_strndup(&ret->ext.hostname, as->tlsext_hostname))
         goto err;
 
 #ifndef OPENSSL_NO_PSK
@@ -325,13 +325,13 @@ SSL_SESSION *d2i_SSL_SESSION(SSL_SESSION **a, const unsigned char **pp,
         goto err;
 #endif
 
-    ret->tlsext_tick_lifetime_hint = as->tlsext_tick_lifetime_hint;
+    ret->ext.tick_lifetime_hint = as->tlsext_tick_lifetime_hint;
     if (as->tlsext_tick) {
-        ret->tlsext_tick = as->tlsext_tick->data;
-        ret->tlsext_ticklen = as->tlsext_tick->length;
+        ret->ext.tick = as->tlsext_tick->data;
+        ret->ext.ticklen = as->tlsext_tick->length;
         as->tlsext_tick->data = NULL;
     } else {
-        ret->tlsext_tick = NULL;
+        ret->ext.tick = NULL;
     }
 #ifndef OPENSSL_NO_COMP
     if (as->comp_id) {
diff --git a/ssl/ssl_lib.c b/ssl/ssl_lib.c
index 65e3ba1824..ddc2ff78e7 100644
--- a/ssl/ssl_lib.c
+++ b/ssl/ssl_lib.c
@@ -589,49 +589,46 @@ SSL *SSL_new(SSL_CTX *ctx)
 
     SSL_CTX_up_ref(ctx);
     s->ctx = ctx;
-    s->tlsext_debug_cb = 0;
-    s->tlsext_debug_arg = NULL;
-    s->tlsext_ticket_expected = 0;
-    s->tlsext_status_type = ctx->tlsext_status_type;
-    s->tlsext_status_expected = 0;
-    s->tlsext_ocsp_ids = NULL;
-    s->tlsext_ocsp_exts = NULL;
-    s->tlsext_ocsp_resp = NULL;
-    s->tlsext_ocsp_resplen = 0;
+    s->ext.debug_cb = 0;
+    s->ext.debug_arg = NULL;
+    s->ext.ticket_expected = 0;
+    s->ext.status_type = ctx->ext.status_type;
+    s->ext.status_expected = 0;
+    s->ext.ocsp.ids = NULL;
+    s->ext.ocsp.exts = NULL;
+    s->ext.ocsp.resp = NULL;
+    s->ext.ocsp.resp_len = 0;
     SSL_CTX_up_ref(ctx);
     s->initial_ctx = ctx;
 #ifndef OPENSSL_NO_EC
-    if (ctx->tlsext_ecpointformatlist) {
-        s->tlsext_ecpointformatlist =
-            OPENSSL_memdup(ctx->tlsext_ecpointformatlist,
-                           ctx->tlsext_ecpointformatlist_length);
-        if (!s->tlsext_ecpointformatlist)
+    if (ctx->ext.ecpointformats) {
+        s->ext.ecpointformats =
+            OPENSSL_memdup(ctx->ext.ecpointformats,
+                           ctx->ext.ecpointformats_len);
+        if (!s->ext.ecpointformats)
             goto err;
-        s->tlsext_ecpointformatlist_length =
-            ctx->tlsext_ecpointformatlist_length;
-    }
-    if (ctx->tlsext_supportedgroupslist) {
-        s->tlsext_supportedgroupslist =
-            OPENSSL_memdup(ctx->tlsext_supportedgroupslist,
-                           ctx->tlsext_supportedgroupslist_length);
-        if (!s->tlsext_supportedgroupslist)
+        s->ext.ecpointformats_len =
+            ctx->ext.ecpointformats_len;
+    }
+    if (ctx->ext.supportedgroups) {
+        s->ext.supportedgroups =
+            OPENSSL_memdup(ctx->ext.supportedgroups,
+                           ctx->ext.supportedgroups_len);
+        if (!s->ext.supportedgroups)
             goto err;
-        s->tlsext_supportedgroupslist_length =
-            ctx->tlsext_supportedgroupslist_length;
+        s->ext.supportedgroups_len = ctx->ext.supportedgroups_len;
     }
 #endif
 #ifndef OPENSSL_NO_NEXTPROTONEG
-    s->next_proto_negotiated = NULL;
+    s->ext.npn = NULL;
 #endif
 
-    if (s->ctx->alpn_client_proto_list) {
-        s->alpn_client_proto_list =
-            OPENSSL_malloc(s->ctx->alpn_client_proto_list_len);
-        if (s->alpn_client_proto_list == NULL)
+    if (s->ctx->ext.alpn) {
+        s->ext.alpn = OPENSSL_malloc(s->ctx->ext.alpn_len);
+        if (s->ext.alpn == NULL)
             goto err;
-        memcpy(s->alpn_client_proto_list, s->ctx->alpn_client_proto_list,
-               s->ctx->alpn_client_proto_list_len);
-        s->alpn_client_proto_list_len = s->ctx->alpn_client_proto_list_len;
+        memcpy(s->ext.alpn, s->ctx->ext.alpn, s->ctx->ext.alpn_len);
+        s->ext.alpn_len = s->ctx->ext.alpn_len;
     }
 
     s->verified_chain = NULL;
@@ -838,7 +835,7 @@ int SSL_dane_enable(SSL *s, const char *basedomain)
      * accepts them and disables host name checks.  To avoid side-effects with
      * invalid input, set the SNI name first.
      */
-    if (s->tlsext_hostname == NULL) {
+    if (s->ext.hostname == NULL) {
         if (!SSL_set_tlsext_host_name(s, basedomain)) {
             SSLerr(SSL_F_SSL_DANE_ENABLE, SSL_R_ERROR_SETTING_TLSA_BASE_DOMAIN);
             return -1;
@@ -997,22 +994,22 @@ void SSL_free(SSL *s)
     ssl_cert_free(s->cert);
     /* Free up if allocated */
 
-    OPENSSL_free(s->tlsext_hostname);
+    OPENSSL_free(s->ext.hostname);
     SSL_CTX_free(s->initial_ctx);
 #ifndef OPENSSL_NO_EC
-    OPENSSL_free(s->tlsext_ecpointformatlist);
-    OPENSSL_free(s->tlsext_supportedgroupslist);
+    OPENSSL_free(s->ext.ecpointformats);
+    OPENSSL_free(s->ext.supportedgroups);
 #endif                          /* OPENSSL_NO_EC */
-    sk_X509_EXTENSION_pop_free(s->tlsext_ocsp_exts, X509_EXTENSION_free);
+    sk_X509_EXTENSION_pop_free(s->ext.ocsp.exts, X509_EXTENSION_free);
 #ifndef OPENSSL_NO_OCSP
-    sk_OCSP_RESPID_pop_free(s->tlsext_ocsp_ids, OCSP_RESPID_free);
+    sk_OCSP_RESPID_pop_free(s->ext.ocsp.ids, OCSP_RESPID_free);
 #endif
 #ifndef OPENSSL_NO_CT
     SCT_LIST_free(s->scts);
-    OPENSSL_free(s->tlsext_scts);
+    OPENSSL_free(s->ext.scts);
 #endif
-    OPENSSL_free(s->tlsext_ocsp_resp);
-    OPENSSL_free(s->alpn_client_proto_list);
+    OPENSSL_free(s->ext.ocsp.resp);
+    OPENSSL_free(s->ext.alpn);
 
     sk_X509_NAME_pop_free(s->client_CA, X509_NAME_free);
 
@@ -1028,7 +1025,7 @@ void SSL_free(SSL *s)
     ASYNC_WAIT_CTX_free(s->waitctx);
 
 #if !defined(OPENSSL_NO_NEXTPROTONEG)
-    OPENSSL_free(s->next_proto_negotiated);
+    OPENSSL_free(s->ext.npn);
 #endif
 
 #ifndef OPENSSL_NO_SRTP
@@ -2168,15 +2165,15 @@ const char *SSL_get_servername(const SSL *s, const int type)
     if (type != TLSEXT_NAMETYPE_host_name)
         return NULL;
 
-    return s->session && !s->tlsext_hostname ?
-        s->session->tlsext_hostname : s->tlsext_hostname;
+    return s->session && !s->ext.hostname ?
+        s->session->ext.hostname : s->ext.hostname;
 }
 
 int SSL_get_servername_type(const SSL *s)
 {
     if (s->session
-        && (!s->tlsext_hostname ? s->session->
-            tlsext_hostname : s->tlsext_hostname))
+        && (!s->ext.hostname ? s->session->
+            ext.hostname : s->ext.hostname))
         return TLSEXT_NAMETYPE_host_name;
     return -1;
 }
@@ -2251,16 +2248,16 @@ int SSL_select_next_proto(unsigned char **out, unsigned char *outlen,
 void SSL_get0_next_proto_negotiated(const SSL *s, const unsigned char **data,
                                     unsigned *len)
 {
-    *data = s->next_proto_negotiated;
+    *data = s->ext.npn;
     if (!*data) {
         *len = 0;
     } else {
-        *len = (unsigned int)s->next_proto_negotiated_len;
+        *len = (unsigned int)s->ext.npn_len;
     }
 }
 
 /*
- * SSL_CTX_set_next_protos_advertised_cb sets a callback that is called when
+ * SSL_CTX_set_npn_advertised_cb sets a callback that is called when
  * a TLS server needs a list of supported protocols for Next Protocol
  * Negotiation. The returned list must be in wire format.  The list is
  * returned by setting |out| to point to it and |outlen| to its length. This
@@ -2269,15 +2266,15 @@ void SSL_get0_next_proto_negotiated(const SSL *s, const unsigned char **data,
  * wishes to advertise. Otherwise, no such extension will be included in the
  * ServerHello.
  */
-void SSL_CTX_set_next_protos_advertised_cb(SSL_CTX *ctx,
-                                           int (*cb) (SSL *ssl,
-                                                      const unsigned char
-                                                      **out,
-                                                      unsigned int *outlen,
-                                                      void *arg), void *arg)
+void SSL_CTX_set_npn_advertised_cb(SSL_CTX *ctx,
+                                   int (*cb) (SSL *ssl,
+                                              const unsigned char **out,
+                                              unsigned int *outlen,
+                                              void *arg),
+                                   void *arg)
 {
-    ctx->next_protos_advertised_cb = cb;
-    ctx->next_protos_advertised_cb_arg = arg;
+    ctx->ext.npn_advertised_cb = cb;
+    ctx->ext.npn_advertised_cb_arg = arg;
 }
 
 /*
@@ -2290,15 +2287,16 @@ void SSL_CTX_set_next_protos_advertised_cb(SSL_CTX *ctx,
  * select a protocol. It is fatal to the connection if this callback returns
  * a value other than SSL_TLSEXT_ERR_OK.
  */
-void SSL_CTX_set_next_proto_select_cb(SSL_CTX *ctx,
-                                      int (*cb) (SSL *s, unsigned char **out,
-                                                 unsigned char *outlen,
-                                                 const unsigned char *in,
-                                                 unsigned int inlen,
-                                                 void *arg), void *arg)
+void SSL_CTX_set_npn_select_cb(SSL_CTX *ctx,
+                               int (*cb) (SSL *s, unsigned char **out,
+                                          unsigned char *outlen,
+                                          const unsigned char *in,
+                                          unsigned int inlen,
+                                          void *arg),
+                               void *arg)
 {
-    ctx->next_proto_select_cb = cb;
-    ctx->next_proto_select_cb_arg = arg;
+    ctx->ext.npn_select_cb = cb;
+    ctx->ext.npn_select_cb_arg = arg;
 }
 #endif
 
@@ -2310,13 +2308,13 @@ void SSL_CTX_set_next_proto_select_cb(SSL_CTX *ctx,
 int SSL_CTX_set_alpn_protos(SSL_CTX *ctx, const unsigned char *protos,
                             unsigned int protos_len)
 {
-    OPENSSL_free(ctx->alpn_client_proto_list);
-    ctx->alpn_client_proto_list = OPENSSL_memdup(protos, protos_len);
-    if (ctx->alpn_client_proto_list == NULL) {
+    OPENSSL_free(ctx->ext.alpn);
+    ctx->ext.alpn = OPENSSL_memdup(protos, protos_len);
+    if (ctx->ext.alpn == NULL) {
         SSLerr(SSL_F_SSL_CTX_SET_ALPN_PROTOS, ERR_R_MALLOC_FAILURE);
         return 1;
     }
-    ctx->alpn_client_proto_list_len = protos_len;
+    ctx->ext.alpn_len = protos_len;
 
     return 0;
 }
@@ -2329,13 +2327,13 @@ int SSL_CTX_set_alpn_protos(SSL_CTX *ctx, const unsigned char *protos,
 int SSL_set_alpn_protos(SSL *ssl, const unsigned char *protos,
                         unsigned int protos_len)
 {
-    OPENSSL_free(ssl->alpn_client_proto_list);
-    ssl->alpn_client_proto_list = OPENSSL_memdup(protos, protos_len);
-    if (ssl->alpn_client_proto_list == NULL) {
+    OPENSSL_free(ssl->ext.alpn);
+    ssl->ext.alpn = OPENSSL_memdup(protos, protos_len);
+    if (ssl->ext.alpn == NULL) {
         SSLerr(SSL_F_SSL_SET_ALPN_PROTOS, ERR_R_MALLOC_FAILURE);
         return 1;
     }
-    ssl->alpn_client_proto_list_len = protos_len;
+    ssl->ext.alpn_len = protos_len;
 
     return 0;
 }
@@ -2353,8 +2351,8 @@ void SSL_CTX_set_alpn_select_cb(SSL_CTX *ctx,
                                            unsigned int inlen,
                                            void *arg), void *arg)
 {
-    ctx->alpn_select_cb = cb;
-    ctx->alpn_select_cb_arg = arg;
+    ctx->ext.alpn_select_cb = cb;
+    ctx->ext.alpn_select_cb_arg = arg;
 }
 
 /*
@@ -2513,12 +2511,12 @@ SSL_CTX *SSL_CTX_new(const SSL_METHOD *meth)
     ret->split_send_fragment = SSL3_RT_MAX_PLAIN_LENGTH;
 
     /* Setup RFC5077 ticket keys */
-    if ((RAND_bytes(ret->tlsext_tick_key_name,
-                    sizeof(ret->tlsext_tick_key_name)) <= 0)
-        || (RAND_bytes(ret->tlsext_tick_hmac_key,
-                       sizeof(ret->tlsext_tick_hmac_key)) <= 0)
-        || (RAND_bytes(ret->tlsext_tick_aes_key,
-                       sizeof(ret->tlsext_tick_aes_key)) <= 0))
+    if ((RAND_bytes(ret->ext.tick_key_name,
+                    sizeof(ret->ext.tick_key_name)) <= 0)
+        || (RAND_bytes(ret->ext.tick_hmac_key,
+                       sizeof(ret->ext.tick_hmac_key)) <= 0)
+        || (RAND_bytes(ret->ext.tick_aes_key,
+                       sizeof(ret->ext.tick_aes_key)) <= 0))
         ret->options |= SSL_OP_NO_TICKET;
 
 #ifndef OPENSSL_NO_SRP
@@ -2556,7 +2554,7 @@ SSL_CTX *SSL_CTX_new(const SSL_METHOD *meth)
      */
     ret->options |= SSL_OP_NO_COMPRESSION;
 
-    ret->tlsext_status_type = TLSEXT_STATUSTYPE_nothing;
+    ret->ext.status_type = TLSEXT_STATUSTYPE_nothing;
 
     return ret;
  err:
@@ -2629,10 +2627,10 @@ void SSL_CTX_free(SSL_CTX *a)
 #endif
 
 #ifndef OPENSSL_NO_EC
-    OPENSSL_free(a->tlsext_ecpointformatlist);
-    OPENSSL_free(a->tlsext_supportedgroupslist);
+    OPENSSL_free(a->ext.ecpointformats);
+    OPENSSL_free(a->ext.supportedgroups);
 #endif
-    OPENSSL_free(a->alpn_client_proto_list);
+    OPENSSL_free(a->ext.alpn);
 
     CRYPTO_THREAD_lock_free(a->lock);
 
@@ -4040,9 +4038,9 @@ static int ct_extract_tls_extension_scts(SSL *s)
 {
     int scts_extracted = 0;
 
-    if (s->tlsext_scts != NULL) {
-        const unsigned char *p = s->tlsext_scts;
-        STACK_OF(SCT) *scts = o2i_SCT_LIST(NULL, &p, s->tlsext_scts_len);
+    if (s->ext.scts != NULL) {
+        const unsigned char *p = s->ext.scts;
+        STACK_OF(SCT) *scts = o2i_SCT_LIST(NULL, &p, s->ext.scts_len);
 
         scts_extracted = ct_move_scts(&s->scts, scts, SCT_SOURCE_TLS_EXTENSION);
 
@@ -4070,11 +4068,11 @@ static int ct_extract_ocsp_response_scts(SSL *s)
     STACK_OF(SCT) *scts = NULL;
     int i;
 
-    if (s->tlsext_ocsp_resp == NULL || s->tlsext_ocsp_resplen == 0)
+    if (s->ext.ocsp.resp == NULL || s->ext.ocsp.resp_len == 0)
         goto err;
 
-    p = s->tlsext_ocsp_resp;
-    rsp = d2i_OCSP_RESPONSE(NULL, &p, (int)s->tlsext_ocsp_resplen);
+    p = s->ext.ocsp.resp;
+    rsp = d2i_OCSP_RESPONSE(NULL, &p, (int)s->ext.ocsp.resp_len);
     if (rsp == NULL)
         goto err;
 
diff --git a/ssl/ssl_locl.h b/ssl/ssl_locl.h
index c1b331a1a7..06557bb4b2 100644
--- a/ssl/ssl_locl.h
+++ b/ssl/ssl_locl.h
@@ -553,18 +553,21 @@ struct ssl_session_st {
      * implement a maximum cache size.
      */
     struct ssl_session_st *prev, *next;
-    char *tlsext_hostname;
+
+    struct {
+        char *hostname;
 # ifndef OPENSSL_NO_EC
-    size_t tlsext_ecpointformatlist_length;
-    unsigned char *tlsext_ecpointformatlist; /* peer's list */
-    size_t tlsext_supportedgroupslist_length;
-    unsigned char *tlsext_supportedgroupslist; /* peer's list */
+        size_t ecpointformats_len;
+        unsigned char *ecpointformats; /* peer's list */
+        size_t supportedgroups_len;
+        unsigned char *supportedgroups; /* peer's list */
 # endif                         /* OPENSSL_NO_EC */
     /* RFC4507 info */
-    unsigned char *tlsext_tick; /* Session ticket */
-    size_t tlsext_ticklen;      /* Session ticket length */
-    unsigned long tlsext_tick_lifetime_hint; /* Session lifetime hint in
-                                              * seconds */
+        unsigned char *tick; /* Session ticket */
+        size_t ticklen;      /* Session ticket length */
+        /* Session lifetime hint in seconds */
+        unsigned long tick_lifetime_hint;
+    } ext;
 # ifndef OPENSSL_NO_SRP
     char *srp_username;
 # endif
@@ -775,63 +778,40 @@ struct ssl_ctx_st {
     ENGINE *client_cert_engine;
 # endif
 
-    /* TLS extensions servername callback */
-    int (*tlsext_servername_callback) (SSL *, int *, void *);
-    void *tlsext_servername_arg;
-    /* RFC 4507 session ticket keys */
-    unsigned char tlsext_tick_key_name[TLSEXT_KEYNAME_LENGTH];
-    unsigned char tlsext_tick_hmac_key[32];
-    unsigned char tlsext_tick_aes_key[32];
-    /* Callback to support customisation of ticket key setting */
-    int (*tlsext_ticket_key_cb) (SSL *ssl,
-                                 unsigned char *name, unsigned char *iv,
-                                 EVP_CIPHER_CTX *ectx, HMAC_CTX *hctx, int enc);
-
-    /* certificate status request info */
-    /* Callback for status request */
-    int (*tlsext_status_cb) (SSL *ssl, void *arg);
-    void *tlsext_status_arg;
-
-# ifndef OPENSSL_NO_PSK
-    unsigned int (*psk_client_callback) (SSL *ssl, const char *hint,
-                                         char *identity,
-                                         unsigned int max_identity_len,
-                                         unsigned char *psk,
-                                         unsigned int max_psk_len);
-    unsigned int (*psk_server_callback) (SSL *ssl, const char *identity,
-                                         unsigned char *psk,
-                                         unsigned int max_psk_len);
-# endif
+    /* TLS extensions. */
+    struct {
+        /* TLS extensions servername callback */
+        int (*servername_cb) (SSL *, int *, void *);
+        void *servername_arg;
+        /* RFC 4507 session ticket keys */
+        unsigned char tick_key_name[TLSEXT_KEYNAME_LENGTH];
+        unsigned char tick_hmac_key[32];
+        unsigned char tick_aes_key[32];
+        /* Callback to support customisation of ticket key setting */
+        int (*ticket_key_cb) (SSL *ssl,
+                              unsigned char *name, unsigned char *iv,
+                              EVP_CIPHER_CTX *ectx, HMAC_CTX *hctx, int enc);
+
+        /* certificate status request info */
+        /* Callback for status request */
+        int (*status_cb) (SSL *ssl, void *arg);
+        void *status_arg;
+        /* ext status type used for CSR extension (OCSP Stapling) */
+        int status_type;
 
-# ifndef OPENSSL_NO_SRP
-    SRP_CTX srp_ctx;            /* ctx for SRP authentication */
-# endif
+# ifndef OPENSSL_NO_EC
+        /* EC extension values inherited by SSL structure */
+        size_t ecpointformats_len;
+        unsigned char *ecpointformats;
+        size_t supportedgroups_len;
+        unsigned char *supportedgroups;
+# endif                         /* OPENSSL_NO_EC */
 
 # ifndef OPENSSL_NO_NEXTPROTONEG
-    /* Next protocol negotiation information */
-
-    /*
-     * For a server, this contains a callback function by which the set of
-     * advertised protocols can be provided.
-     */
-    int (*next_protos_advertised_cb) (SSL *s, const unsigned char **buf,
-                                      unsigned int *len, void *arg);
-    void *next_protos_advertised_cb_arg;
-    /*
-     * For a client, this contains a callback function that selects the next
-     * protocol from the list provided by the server.
-     */
-    int (*next_proto_select_cb) (SSL *s, unsigned char **out,
-                                 unsigned char *outlen,
-                                 const unsigned char *in,
-                                 unsigned int inlen, void *arg);
-    void *next_proto_se