Ensure that we never select compression in TLSv1.3
[openssl.git] / ssl / statem / statem_clnt.c
index d0d384c14b2095ba6a8a54d9f56865eec996c0a2..abddc0ace375f7da3b69c3cc50785b28937d1ad4 100644 (file)
@@ -48,6 +48,7 @@
  */
 
 #include <stdio.h>
+#include <time.h>
 #include "../ssl_locl.h"
 #include "statem_locl.h"
 #include <openssl/buffer.h>
@@ -59,6 +60,7 @@
 #include <openssl/bn.h>
 #include <openssl/engine.h>
 
+static MSG_PROCESS_RETURN tls_process_hello_retry_request(SSL *s, PACKET *pkt);
 static MSG_PROCESS_RETURN tls_process_encrypted_extensions(SSL *s, PACKET *pkt);
 
 static ossl_inline int cert_req_allowed(SSL *s);
@@ -136,6 +138,17 @@ static int ossl_statem_client13_read_transition(SSL *s, int mt)
     default:
         break;
 
+    case TLS_ST_CW_CLNT_HELLO:
+        /*
+         * This must a ClientHello following a HelloRetryRequest, so the only
+         * thing we can get now is a ServerHello.
+         */
+        if (mt == SSL3_MT_SERVER_HELLO) {
+            st->hand_state = TLS_ST_CR_SRVR_HELLO;
+            return 1;
+        }
+        break;
+
     case TLS_ST_CR_SRVR_HELLO:
         if (mt == SSL3_MT_ENCRYPTED_EXTENSIONS) {
             st->hand_state = TLS_ST_CR_ENCRYPTED_EXTENSIONS;
@@ -169,12 +182,29 @@ static int ossl_statem_client13_read_transition(SSL *s, int mt)
         break;
 
     case TLS_ST_CR_CERT:
+        if (mt == SSL3_MT_CERTIFICATE_VERIFY) {
+            st->hand_state = TLS_ST_CR_CERT_VRFY;
+            return 1;
+        }
+        break;
+
+    case TLS_ST_CR_CERT_VRFY:
         if (mt == SSL3_MT_FINISHED) {
             st->hand_state = TLS_ST_CR_FINISHED;
             return 1;
         }
         break;
 
+    case TLS_ST_OK:
+        if (mt == SSL3_MT_NEWSESSION_TICKET) {
+            st->hand_state = TLS_ST_CR_SESSION_TICKET;
+            return 1;
+        }
+        if (mt == SSL3_MT_KEY_UPDATE) {
+            st->hand_state = TLS_ST_CR_KEY_UPDATE;
+            return 1;
+        }
+        break;
     }
 
     /* No valid transition found */
@@ -196,8 +226,8 @@ int ossl_statem_client_read_transition(SSL *s, int mt)
     int ske_expected;
 
     /*
-     * Note that after a ClientHello we don't know what version we are going
-     * to negotiate yet, so we don't take this branch until later
+     * Note that after writing the first ClientHello we don't know what version
+     * we are going to negotiate yet, so we don't take this branch until later.
      */
     if (SSL_IS_TLS13(s)) {
         if (!ossl_statem_client13_read_transition(s, mt))
@@ -220,6 +250,11 @@ int ossl_statem_client_read_transition(SSL *s, int mt)
                 st->hand_state = DTLS_ST_CR_HELLO_VERIFY_REQUEST;
                 return 1;
             }
+        } else {
+            if (mt == SSL3_MT_HELLO_RETRY_REQUEST) {
+                st->hand_state = TLS_ST_CR_HELLO_RETRY_REQUEST;
+                return 1;
+            }
         }
         break;
 
@@ -345,6 +380,13 @@ int ossl_statem_client_read_transition(SSL *s, int mt)
             return 1;
         }
         break;
+
+    case TLS_ST_OK:
+        if (mt == SSL3_MT_HELLO_REQUEST) {
+            st->hand_state = TLS_ST_CR_HELLO_REQ;
+            return 1;
+        }
+        break;
     }
 
  err:
@@ -364,20 +406,23 @@ static WRITE_TRAN ossl_statem_client13_write_transition(SSL *s)
     OSSL_STATEM *st = &s->statem;
 
     /*
-     * TODO(TLS1.3): This is still based on the TLSv1.2 state machine. Over time
-     * we will update this to look more like real TLSv1.3
-     */
-
-    /*
-     * Note: There are no cases for TLS_ST_BEFORE or TLS_ST_CW_CLNT_HELLO,
-     * because we haven't negotiated TLSv1.3 yet at that point. They are
-     * handled by ossl_statem_client_write_transition().
+     * Note: There are no cases for TLS_ST_BEFORE because we haven't negotiated
+     * TLSv1.3 yet at that point. They are handled by
+     * ossl_statem_client_write_transition().
      */
     switch (st->hand_state) {
     default:
         /* Shouldn't happen */
         return WRITE_TRAN_ERROR;
 
+    case TLS_ST_CW_CLNT_HELLO:
+        /* We only hit this in the case of HelloRetryRequest */
+        return WRITE_TRAN_FINISHED;
+
+    case TLS_ST_CR_HELLO_RETRY_REQUEST:
+        st->hand_state = TLS_ST_CW_CLNT_HELLO;
+        return WRITE_TRAN_CONTINUE;
+
     case TLS_ST_CR_FINISHED:
         st->hand_state = (s->s3->tmp.cert_req != 0) ? TLS_ST_CW_CERT
                                                     : TLS_ST_CW_FINISHED;
@@ -393,10 +438,28 @@ static WRITE_TRAN ossl_statem_client13_write_transition(SSL *s)
         st->hand_state = TLS_ST_CW_FINISHED;
         return WRITE_TRAN_CONTINUE;
 
+    case TLS_ST_CR_KEY_UPDATE:
+        if (s->key_update != SSL_KEY_UPDATE_NONE) {
+            st->hand_state = TLS_ST_CW_KEY_UPDATE;
+            return WRITE_TRAN_CONTINUE;
+        }
+        /* Fall through */
+
+    case TLS_ST_CW_KEY_UPDATE:
+    case TLS_ST_CR_SESSION_TICKET:
     case TLS_ST_CW_FINISHED:
         st->hand_state = TLS_ST_OK;
         ossl_statem_set_in_init(s, 0);
         return WRITE_TRAN_CONTINUE;
+
+    case TLS_ST_OK:
+        if (s->key_update != SSL_KEY_UPDATE_NONE) {
+            st->hand_state = TLS_ST_CW_KEY_UPDATE;
+            return WRITE_TRAN_CONTINUE;
+        }
+
+        /* Try to read from the server instead */
+        return WRITE_TRAN_FINISHED;
     }
 }
 
@@ -422,6 +485,13 @@ WRITE_TRAN ossl_statem_client_write_transition(SSL *s)
         return WRITE_TRAN_ERROR;
 
     case TLS_ST_OK:
+        if (!s->renegotiate) {
+            /*
+             * We haven't requested a renegotiation ourselves so we must have
+             * received a message from the server. Better read it.
+             */
+            return WRITE_TRAN_FINISHED;
+        }
         /* Renegotiation - fall through */
     case TLS_ST_BEFORE:
         st->hand_state = TLS_ST_CW_CLNT_HELLO;
@@ -509,6 +579,23 @@ WRITE_TRAN ossl_statem_client_write_transition(SSL *s)
             ossl_statem_set_in_init(s, 0);
             return WRITE_TRAN_CONTINUE;
         }
+
+    case TLS_ST_CR_HELLO_REQ:
+        /*
+         * If we can renegotiate now then do so, otherwise wait for a more
+         * convenient time.
+         */
+        if (ssl3_renegotiate_check(s, 1)) {
+            if (!tls_setup_handshake(s)) {
+                ossl_statem_set_error(s);
+                return WRITE_TRAN_ERROR;
+            }
+            st->hand_state = TLS_ST_CW_CLNT_HELLO;
+            return WRITE_TRAN_CONTINUE;
+        }
+        st->hand_state = TLS_ST_OK;
+        ossl_statem_set_in_init(s, 0);
+        return WRITE_TRAN_CONTINUE;
     }
 }
 
@@ -553,7 +640,7 @@ WORK_STATE ossl_statem_client_pre_work(SSL *s, WORK_STATE wst)
         break;
 
     case TLS_ST_OK:
-        return tls_finish_handshake(s, wst);
+        return tls_finish_handshake(s, wst, 1);
     }
 
     return WORK_FINISHED_CONTINUE;
@@ -642,6 +729,13 @@ WORK_STATE ossl_statem_client_post_work(SSL *s, WORK_STATE wst)
             return WORK_ERROR;
         }
         break;
+
+    case TLS_ST_CW_KEY_UPDATE:
+        if (statem_flush(s) != 1)
+            return WORK_MORE_A;
+        if (!tls13_update_key(s, 1))
+            return WORK_ERROR;
+        break;
     }
 
     return WORK_FINISHED_CONTINUE;
@@ -703,6 +797,11 @@ int ossl_statem_client_construct_message(SSL *s, WPACKET *pkt,
         *confunc = tls_construct_finished;
         *mt = SSL3_MT_FINISHED;
         break;
+
+    case TLS_ST_CW_KEY_UPDATE:
+        *confunc = tls_construct_key_update;
+        *mt = SSL3_MT_KEY_UPDATE;
+        break;
     }
 
     return 1;
@@ -727,9 +826,15 @@ size_t ossl_statem_client_max_message_size(SSL *s)
     case DTLS_ST_CR_HELLO_VERIFY_REQUEST:
         return HELLO_VERIFY_REQUEST_MAX_LENGTH;
 
+    case TLS_ST_CR_HELLO_RETRY_REQUEST:
+        return HELLO_RETRY_REQUEST_MAX_LENGTH;
+
     case TLS_ST_CR_CERT:
         return s->max_cert_list;
 
+    case TLS_ST_CR_CERT_VRFY:
+        return SSL3_RT_MAX_PLAIN_LENGTH;
+
     case TLS_ST_CR_CERT_STATUS:
         return SSL3_RT_MAX_PLAIN_LENGTH;
 
@@ -760,6 +865,9 @@ size_t ossl_statem_client_max_message_size(SSL *s)
 
     case TLS_ST_CR_ENCRYPTED_EXTENSIONS:
         return ENCRYPTED_EXTENSIONS_MAX_LENGTH;
+
+    case TLS_ST_CR_KEY_UPDATE:
+        return KEY_UPDATE_MAX_LENGTH;
     }
 }
 
@@ -781,9 +889,15 @@ MSG_PROCESS_RETURN ossl_statem_client_process_message(SSL *s, PACKET *pkt)
     case DTLS_ST_CR_HELLO_VERIFY_REQUEST:
         return dtls_process_hello_verify(s, pkt);
 
+    case TLS_ST_CR_HELLO_RETRY_REQUEST:
+        return tls_process_hello_retry_request(s, pkt);
+
     case TLS_ST_CR_CERT:
         return tls_process_server_certificate(s, pkt);
 
+    case TLS_ST_CR_CERT_VRFY:
+        return tls_process_cert_verify(s, pkt);
+
     case TLS_ST_CR_CERT_STATUS:
         return tls_process_cert_status(s, pkt);
 
@@ -805,8 +919,14 @@ MSG_PROCESS_RETURN ossl_statem_client_process_message(SSL *s, PACKET *pkt)
     case TLS_ST_CR_FINISHED:
         return tls_process_finished(s, pkt);
 
+    case TLS_ST_CR_HELLO_REQ:
+        return tls_process_hello_req(s, pkt);
+
     case TLS_ST_CR_ENCRYPTED_EXTENSIONS:
         return tls_process_encrypted_extensions(s, pkt);
+
+    case TLS_ST_CR_KEY_UPDATE:
+        return tls_process_key_update(s, pkt);
     }
 }
 
@@ -879,6 +999,9 @@ int tls_construct_client_hello(SSL *s, WPACKET *pkt)
     }
     /* else use the pre-loaded session */
 
+    /* This is a real handshake so make sure we clean it up at the end */
+    s->statem.cleanuphand = 1;
+
     p = s->s3->client_random;
 
     /*
@@ -940,7 +1063,7 @@ int tls_construct_client_hello(SSL *s, WPACKET *pkt)
     }
 
     /* Session ID */
-    if (s->new_session)
+    if (s->new_session || s->session->ssl_version == TLS1_3_VERSION)
         sess_id_len = 0;
     else
         sess_id_len = s->session->session_id_length;
@@ -982,7 +1105,9 @@ int tls_construct_client_hello(SSL *s, WPACKET *pkt)
         return 0;
     }
 #ifndef OPENSSL_NO_COMP
-    if (ssl_allow_compression(s) && s->ctx->comp_methods) {
+    if (ssl_allow_compression(s)
+            && s->ctx->comp_methods
+            && (SSL_IS_DTLS(s) || s->s3->tmp.max_ver < TLS1_3_VERSION)) {
         int compnum = sk_SSL_COMP_num(s->ctx->comp_methods);
         for (i = 0; i < compnum; i++) {
             comp = sk_SSL_COMP_value(s->ctx->comp_methods, i);
@@ -1066,6 +1191,7 @@ MSG_PROCESS_RETURN tls_process_server_hello(SSL *s, PACKET *pkt)
         goto f_err;
     }
 
+    /* We do this immediately so we know what format the ServerHello is in */
     protverr = ssl_choose_client_version(s, sversion);
     if (protverr != 0) {
         al = SSL_AD_PROTOCOL_VERSION;
@@ -1081,8 +1207,6 @@ MSG_PROCESS_RETURN tls_process_server_hello(SSL *s, PACKET *pkt)
         goto f_err;
     }
 
-    s->hit = 0;
-
     /* Get the session-id. */
     if (!SSL_IS_TLS13(s)) {
         if (!PACKET_get_length_prefixed_1(pkt, &session_id)) {
@@ -1109,63 +1233,103 @@ MSG_PROCESS_RETURN tls_process_server_hello(SSL *s, PACKET *pkt)
         goto f_err;
     }
 
-    /*
-     * Check if we can resume the session based on external pre-shared secret.
-     * EAP-FAST (RFC 4851) supports two types of session resumption.
-     * Resumption based on server-side state works with session IDs.
-     * Resumption based on pre-shared Protected Access Credentials (PACs)
-     * works by overriding the SessionTicket extension at the application
-     * layer, and does not send a session ID. (We do not know whether EAP-FAST
-     * servers would honour the session ID.) Therefore, the session ID alone
-     * is not a reliable indicator of session resumption, so we first check if
-     * we can resume, and later peek at the next handshake message to see if the
-     * server wants to resume.
-     */
-    if (s->version >= TLS1_VERSION && !SSL_IS_TLS13(s)
-            && s->ext.session_secret_cb != NULL && s->session->ext.tick) {
-        const SSL_CIPHER *pref_cipher = NULL;
+    if (!SSL_IS_TLS13(s)) {
+        if (!PACKET_get_1(pkt, &compression)) {
+            SSLerr(SSL_F_TLS_PROCESS_SERVER_HELLO, SSL_R_LENGTH_MISMATCH);
+            al = SSL_AD_DECODE_ERROR;
+            goto f_err;
+        }
+    } else {
+        compression = 0;
+    }
+
+    /* TLS extensions */
+    if (PACKET_remaining(pkt) == 0) {
+        PACKET_null_init(&extpkt);
+    } else if (!PACKET_as_length_prefixed_2(pkt, &extpkt)) {
+        al = SSL_AD_DECODE_ERROR;
+        SSLerr(SSL_F_TLS_PROCESS_SERVER_HELLO, SSL_R_BAD_LENGTH);
+        goto f_err;
+    }
+
+    context = SSL_IS_TLS13(s) ? EXT_TLS1_3_SERVER_HELLO
+                              : EXT_TLS1_2_SERVER_HELLO;
+    if (!tls_collect_extensions(s, &extpkt, context, &extensions, &al, NULL))
+        goto f_err;
+
+    s->hit = 0;
+
+    if (SSL_IS_TLS13(s)) {
+        /* This will set s->hit if we are resuming */
+        if (!tls_parse_extension(s, TLSEXT_IDX_psk,
+                                 EXT_TLS1_3_SERVER_HELLO,
+                                 extensions, NULL, 0, &al))
+            goto f_err;
+    } else {
         /*
-         * s->session->master_key_length is a size_t, but this is an int for
-         * backwards compat reasons
+         * Check if we can resume the session based on external pre-shared
+         * secret. EAP-FAST (RFC 4851) supports two types of session resumption.
+         * Resumption based on server-side state works with session IDs.
+         * Resumption based on pre-shared Protected Access Credentials (PACs)
+         * works by overriding the SessionTicket extension at the application
+         * layer, and does not send a session ID. (We do not know whether
+         * EAP-FAST servers would honour the session ID.) Therefore, the session
+         * ID alone is not a reliable indicator of session resumption, so we
+         * first check if we can resume, and later peek at the next handshake
+         * message to see if the server wants to resume.
          */
-        int master_key_length;
-        master_key_length = sizeof(s->session->master_key);
-        if (s->ext.session_secret_cb(s, s->session->master_key,
-                                     &master_key_length,
-                                     NULL, &pref_cipher,
-                                     s->ext.session_secret_cb_arg)
-                 && master_key_length > 0) {
-            s->session->master_key_length = master_key_length;
-            s->session->cipher = pref_cipher ?
-                pref_cipher : ssl_get_cipher_by_char(s, cipherchars);
-        } else {
-            SSLerr(SSL_F_TLS_PROCESS_SERVER_HELLO, ERR_R_INTERNAL_ERROR);
-            al = SSL_AD_INTERNAL_ERROR;
-            goto f_err;
+        if (s->version >= TLS1_VERSION
+                && s->ext.session_secret_cb != NULL && s->session->ext.tick) {
+            const SSL_CIPHER *pref_cipher = NULL;
+            /*
+             * s->session->master_key_length is a size_t, but this is an int for
+             * backwards compat reasons
+             */
+            int master_key_length;
+            master_key_length = sizeof(s->session->master_key);
+            if (s->ext.session_secret_cb(s, s->session->master_key,
+                                         &master_key_length,
+                                         NULL, &pref_cipher,
+                                         s->ext.session_secret_cb_arg)
+                     && master_key_length > 0) {
+                s->session->master_key_length = master_key_length;
+                s->session->cipher = pref_cipher ?
+                    pref_cipher : ssl_get_cipher_by_char(s, cipherchars, 0);
+            } else {
+                SSLerr(SSL_F_TLS_PROCESS_SERVER_HELLO, ERR_R_INTERNAL_ERROR);
+                al = SSL_AD_INTERNAL_ERROR;
+                goto f_err;
+            }
         }
+
+        if (session_id_len != 0
+                && session_id_len == s->session->session_id_length
+                && memcmp(PACKET_data(&session_id), s->session->session_id,
+                          session_id_len) == 0)
+            s->hit = 1;
     }
 
-    if (session_id_len != 0 && session_id_len == s->session->session_id_length
-        && memcmp(PACKET_data(&session_id), s->session->session_id,
-                  session_id_len) == 0) {
+    if (s->hit) {
         if (s->sid_ctx_length != s->session->sid_ctx_length
-            || memcmp(s->session->sid_ctx, s->sid_ctx, s->sid_ctx_length)) {
+                || memcmp(s->session->sid_ctx, s->sid_ctx, s->sid_ctx_length)) {
             /* actually a client application bug */
             al = SSL_AD_ILLEGAL_PARAMETER;
             SSLerr(SSL_F_TLS_PROCESS_SERVER_HELLO,
                    SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT);
             goto f_err;
         }
-        s->hit = 1;
     } else {
         /*
          * If we were trying for session-id reuse but the server
-         * didn't echo the ID, make a new SSL_SESSION.
+         * didn't resume, make a new SSL_SESSION.
          * In the case of EAP-FAST and PAC, we do not send a session ID,
          * so the PAC-based session secret is always preserved. It'll be
          * overwritten if the server refuses resumption.
          */
-        if (s->session->session_id_length > 0) {
+        if (s->session->session_id_length > 0
+                || (SSL_IS_TLS13(s)
+                    && s->session->ext.tick_identity
+                       != TLSEXT_PSK_BAD_IDENTITY)) {
             s->ctx->stats.sess_miss++;
             if (!ssl_get_new_session(s, 0)) {
                 goto f_err;
@@ -1189,7 +1353,7 @@ MSG_PROCESS_RETURN tls_process_server_hello(SSL *s, PACKET *pkt)
         goto f_err;
     }
 
-    c = ssl_get_cipher_by_char(s, cipherchars);
+    c = ssl_get_cipher_by_char(s, cipherchars, 0);
     if (c == NULL) {
         /* unknown cipher */
         al = SSL_AD_ILLEGAL_PARAMETER;
@@ -1235,17 +1399,6 @@ MSG_PROCESS_RETURN tls_process_server_hello(SSL *s, PACKET *pkt)
         goto f_err;
     }
     s->s3->tmp.new_cipher = c;
-    /* lets get the compression algorithm */
-    /* COMPRESSION */
-    if (!SSL_IS_TLS13(s)) {
-        if (!PACKET_get_1(pkt, &compression)) {
-            SSLerr(SSL_F_TLS_PROCESS_SERVER_HELLO, SSL_R_LENGTH_MISMATCH);
-            al = SSL_AD_DECODE_ERROR;
-            goto f_err;
-        }
-    } else {
-        compression = 0;
-    }
 
 #ifdef OPENSSL_NO_COMP
     if (compression != 0) {
@@ -1289,19 +1442,7 @@ MSG_PROCESS_RETURN tls_process_server_hello(SSL *s, PACKET *pkt)
     }
 #endif
 
-    /* TLS extensions */
-    if (PACKET_remaining(pkt) == 0) {
-        PACKET_null_init(&extpkt);
-    } else if (!PACKET_as_length_prefixed_2(pkt, &extpkt)) {
-        al = SSL_AD_DECODE_ERROR;
-        SSLerr(SSL_F_TLS_PROCESS_SERVER_HELLO, SSL_R_BAD_LENGTH);
-        goto f_err;
-    }
-
-    context = SSL_IS_TLS13(s) ? EXT_TLS1_3_SERVER_HELLO
-                              : EXT_TLS1_2_SERVER_HELLO;
-    if (!tls_collect_extensions(s, &extpkt, context, &extensions, &al)
-            || !tls_parse_all_extensions(s, context, extensions, NULL, 0, &al))
+    if (!tls_parse_all_extensions(s, context, extensions, NULL, 0, &al))
         goto f_err;
 
 #ifndef OPENSSL_NO_SCTP
@@ -1352,6 +1493,52 @@ MSG_PROCESS_RETURN tls_process_server_hello(SSL *s, PACKET *pkt)
     return MSG_PROCESS_ERROR;
 }
 
+static MSG_PROCESS_RETURN tls_process_hello_retry_request(SSL *s, PACKET *pkt)
+{
+    unsigned int sversion;
+    int errorcode;
+    RAW_EXTENSION *extensions = NULL;
+    int al;
+    PACKET extpkt;
+
+    if (!PACKET_get_net_2(pkt, &sversion)) {
+        al = SSL_AD_DECODE_ERROR;
+        SSLerr(SSL_F_TLS_PROCESS_HELLO_RETRY_REQUEST, SSL_R_LENGTH_MISMATCH);
+        goto f_err;
+    }
+
+    s->hello_retry_request = 1;
+
+    /* This will fail if it doesn't choose TLSv1.3+ */
+    errorcode = ssl_choose_client_version(s, sversion);
+    if (errorcode != 0) {
+        al = SSL_AD_PROTOCOL_VERSION;
+        SSLerr(SSL_F_TLS_PROCESS_HELLO_RETRY_REQUEST, errorcode);
+        goto f_err;
+    }
+
+    if (!PACKET_as_length_prefixed_2(pkt, &extpkt)) {
+        al = SSL_AD_DECODE_ERROR;
+        SSLerr(SSL_F_TLS_PROCESS_HELLO_RETRY_REQUEST, SSL_R_BAD_LENGTH);
+        goto f_err;
+    }
+
+    if (!tls_collect_extensions(s, &extpkt, EXT_TLS1_3_HELLO_RETRY_REQUEST,
+                                &extensions, &al, NULL)
+            || !tls_parse_all_extensions(s, EXT_TLS1_3_HELLO_RETRY_REQUEST,
+                                         extensions, NULL, 0, &al))
+        goto f_err;
+
+    OPENSSL_free(extensions);
+
+    return MSG_PROCESS_FINISHED_READING;
+ f_err:
+    ssl3_send_alert(s, SSL3_AL_FATAL, al);
+    ossl_statem_set_error(s);
+    OPENSSL_free(extensions);
+    return MSG_PROCESS_ERROR;
+}
+
 MSG_PROCESS_RETURN tls_process_server_certificate(SSL *s, PACKET *pkt)
 {
     int al, i, ret = MSG_PROCESS_ERROR, exp_idx;
@@ -1409,10 +1596,13 @@ MSG_PROCESS_RETURN tls_process_server_certificate(SSL *s, PACKET *pkt)
                 goto f_err;
             }
             if (!tls_collect_extensions(s, &extensions, EXT_TLS1_3_CERTIFICATE,
-                                        &rawexts, &al)
+                                        &rawexts, &al, NULL)
                     || !tls_parse_all_extensions(s, EXT_TLS1_3_CERTIFICATE,
-                                                 rawexts, x, chainidx, &al))
+                                                 rawexts, x, chainidx, &al)) {
+                OPENSSL_free(rawexts);
                 goto f_err;
+            }
+            OPENSSL_free(rawexts);
         }
 
         if (!sk_X509_push(sk, x)) {
@@ -1479,17 +1669,23 @@ MSG_PROCESS_RETURN tls_process_server_certificate(SSL *s, PACKET *pkt)
                SSL_R_UNKNOWN_CERTIFICATE_TYPE);
         goto f_err;
     }
-
-    exp_idx = ssl_cipher_get_cert_index(s->s3->tmp.new_cipher);
-    if (exp_idx >= 0 && i != exp_idx
-        && (exp_idx != SSL_PKEY_GOST_EC ||
-            (i != SSL_PKEY_GOST12_512 && i != SSL_PKEY_GOST12_256
-             && i != SSL_PKEY_GOST01))) {
-        x = NULL;
-        al = SSL_AD_ILLEGAL_PARAMETER;
-        SSLerr(SSL_F_TLS_PROCESS_SERVER_CERTIFICATE,
-               SSL_R_WRONG_CERTIFICATE_TYPE);
-        goto f_err;
+    /*
+     * Check certificate type is consistent with ciphersuite. For TLS 1.3
+     * skip check since TLS 1.3 ciphersuites can be used with any certificate
+     * type.
+     */
+    if (!SSL_IS_TLS13(s)) {
+        exp_idx = ssl_cipher_get_cert_index(s->s3->tmp.new_cipher);
+        if (exp_idx >= 0 && i != exp_idx
+            && (exp_idx != SSL_PKEY_GOST_EC ||
+                (i != SSL_PKEY_GOST12_512 && i != SSL_PKEY_GOST12_256
+                 && i != SSL_PKEY_GOST01))) {
+            x = NULL;
+            al = SSL_AD_ILLEGAL_PARAMETER;
+            SSLerr(SSL_F_TLS_PROCESS_SERVER_CERTIFICATE,
+                   SSL_R_WRONG_CERTIFICATE_TYPE);
+            goto f_err;
+        }
     }
     s->session->peer_type = i;
 
@@ -1497,8 +1693,18 @@ MSG_PROCESS_RETURN tls_process_server_certificate(SSL *s, PACKET *pkt)
     X509_up_ref(x);
     s->session->peer = x;
     s->session->verify_result = s->verify_result;
-
     x = NULL;
+
+    /* Save the current hash state for when we receive the CertificateVerify */
+    if (SSL_IS_TLS13(s)
+            && !ssl_handshake_hash(s, s->cert_verify_hash,
+                                   sizeof(s->cert_verify_hash),
+                                   &s->cert_verify_hash_len)) {
+        al = SSL_AD_INTERNAL_ERROR;
+        SSLerr(SSL_F_TLS_PROCESS_SERVER_CERTIFICATE, ERR_R_INTERNAL_ERROR);
+        goto f_err;
+    }
+
     ret = MSG_PROCESS_CONTINUE_READING;
     goto done;
 
@@ -1613,6 +1819,8 @@ static int tls_process_ske_dhe(SSL *s, PACKET *pkt, EVP_PKEY **pkey, int *al)
     DH *dh = NULL;
     BIGNUM *p = NULL, *g = NULL, *bnpub_key = NULL;
 
+    int check_bits = 0;
+
     if (!PACKET_get_length_prefixed_2(pkt, &prime)
         || !PACKET_get_length_prefixed_2(pkt, &generator)
         || !PACKET_get_length_prefixed_2(pkt, &pub_key)) {
@@ -1642,7 +1850,8 @@ static int tls_process_ske_dhe(SSL *s, PACKET *pkt, EVP_PKEY **pkey, int *al)
         goto err;
     }
 
-    if (BN_is_zero(p) || BN_is_zero(g) || BN_is_zero(bnpub_key)) {
+    /* test non-zero pupkey */
+    if (BN_is_zero(bnpub_key)) {
         *al = SSL_AD_DECODE_ERROR;
         SSLerr(SSL_F_TLS_PROCESS_SKE_DHE, SSL_R_BAD_DH_VALUE);
         goto err;
@@ -1655,6 +1864,12 @@ static int tls_process_ske_dhe(SSL *s, PACKET *pkt, EVP_PKEY **pkey, int *al)
     }
     p = g = NULL;
 
+    if (DH_check_params(dh, &check_bits) == 0 || check_bits != 0) {
+        *al = SSL_AD_DECODE_ERROR;
+        SSLerr(SSL_F_TLS_PROCESS_SKE_DHE, SSL_R_BAD_DH_VALUE);
+        goto err;
+    }
+
     if (!DH_set0_key(dh, bnpub_key, NULL)) {
         *al = SSL_AD_INTERNAL_ERROR;
         SSLerr(SSL_F_TLS_PROCESS_SKE_DHE, ERR_R_BN_LIB);
@@ -1803,6 +2018,8 @@ MSG_PROCESS_RETURN tls_process_key_exchange(SSL *s, PACKET *pkt)
     int al = -1;
     long alg_k;
     EVP_PKEY *pkey = NULL;
+    EVP_MD_CTX *md_ctx = NULL;
+    EVP_PKEY_CTX *pctx = NULL;
     PACKET save_param_start, signature;
 
     alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
@@ -1841,7 +2058,6 @@ MSG_PROCESS_RETURN tls_process_key_exchange(SSL *s, PACKET *pkt)
         PACKET params;
         int maxsig;
         const EVP_MD *md = NULL;
-        EVP_MD_CTX *md_ctx;
 
         /*
          * |pkt| now points to the beginning of the signature, so the difference
@@ -1856,14 +2072,15 @@ MSG_PROCESS_RETURN tls_process_key_exchange(SSL *s, PACKET *pkt)
         }
 
         if (SSL_USE_SIGALGS(s)) {
-            const unsigned char *sigalgs;
+            unsigned int sigalg;
             int rv;
-            if (!PACKET_get_bytes(pkt, &sigalgs, 2)) {
+
+            if (!PACKET_get_net_2(pkt, &sigalg)) {
                 al = SSL_AD_DECODE_ERROR;
                 SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, SSL_R_LENGTH_TOO_SHORT);
                 goto err;
             }
-            rv = tls12_check_peer_sigalg(&md, s, sigalgs, pkey);
+            rv = tls12_check_peer_sigalg(s, sigalg, pkey);
             if (rv == -1) {
                 al = SSL_AD_INTERNAL_ERROR;
                 goto err;
@@ -1874,12 +2091,13 @@ MSG_PROCESS_RETURN tls_process_key_exchange(SSL *s, PACKET *pkt)
 #ifdef SSL_DEBUG
             fprintf(stderr, "USING TLSv1.2 HASH %s\n", EVP_MD_name(md));
 #endif
-        } else if (EVP_PKEY_id(pkey) == EVP_PKEY_RSA) {
-            md = EVP_md5_sha1();
-        } else {
-            md = EVP_sha1();
+        } else if (!tls1_set_peer_legacy_sigalg(s, pkey)) {
+            al = SSL_AD_INTERNAL_ERROR;
+            goto err;
         }
 
+        md = ssl_md(s->s3->tmp.peer_sigalg->hash_idx);
+
         if (!PACKET_get_length_prefixed_2(pkt, &signature)
             || PACKET_remaining(pkt) != 0) {
             al = SSL_AD_DECODE_ERROR;
@@ -1911,29 +2129,39 @@ MSG_PROCESS_RETURN tls_process_key_exchange(SSL *s, PACKET *pkt)
             goto err;
         }
 
-        if (EVP_VerifyInit_ex(md_ctx, md, NULL) <= 0
-            || EVP_VerifyUpdate(md_ctx, &(s->s3->client_random[0]),
-                                SSL3_RANDOM_SIZE) <= 0
-            || EVP_VerifyUpdate(md_ctx, &(s->s3->server_random[0]),
-                                SSL3_RANDOM_SIZE) <= 0
-            || EVP_VerifyUpdate(md_ctx, PACKET_data(&params),
-                                PACKET_remaining(&params)) <= 0) {
-            EVP_MD_CTX_free(md_ctx);
+        if (EVP_DigestVerifyInit(md_ctx, &pctx, md, NULL, pkey) <= 0) {
+            al = SSL_AD_INTERNAL_ERROR;
+            SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, ERR_R_EVP_LIB);
+            goto err;
+        }
+        if (SSL_USE_PSS(s)) {
+            if (EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PSS_PADDING) <= 0
+                || EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx,
+                                                RSA_PSS_SALTLEN_DIGEST) <= 0) {
+                al = SSL_AD_INTERNAL_ERROR;
+                SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, ERR_R_EVP_LIB);
+                goto err;
+            }
+        }
+        if (EVP_DigestVerifyUpdate(md_ctx, &(s->s3->client_random[0]),
+                                   SSL3_RANDOM_SIZE) <= 0
+                || EVP_DigestVerifyUpdate(md_ctx, &(s->s3->server_random[0]),
+                                          SSL3_RANDOM_SIZE) <= 0
+                || EVP_DigestVerifyUpdate(md_ctx, PACKET_data(&params),
+                                          PACKET_remaining(&params)) <= 0) {
             al = SSL_AD_INTERNAL_ERROR;
             SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, ERR_R_EVP_LIB);
             goto err;
         }
-        /* TODO(size_t): Convert this call */
-        if (EVP_VerifyFinal(md_ctx, PACKET_data(&signature),
-                            (unsigned int)PACKET_remaining(&signature),
-                            pkey) <= 0) {
+        if (EVP_DigestVerifyFinal(md_ctx, PACKET_data(&signature),
+                                  PACKET_remaining(&signature)) <= 0) {
             /* bad signature */
-            EVP_MD_CTX_free(md_ctx);
             al = SSL_AD_DECRYPT_ERROR;
             SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, SSL_R_BAD_SIGNATURE);
             goto err;
         }
         EVP_MD_CTX_free(md_ctx);
+        md_ctx = NULL;
     } else {
         /* aNULL, aSRP or PSK do not need public keys */
         if (!(s->s3->tmp.new_cipher->algorithm_auth & (SSL_aNULL | SSL_aSRP))
@@ -1961,61 +2189,68 @@ MSG_PROCESS_RETURN tls_process_key_exchange(SSL *s, PACKET *pkt)
     if (al != -1)
         ssl3_send_alert(s, SSL3_AL_FATAL, al);
     ossl_statem_set_error(s);
+    EVP_MD_CTX_free(md_ctx);
     return MSG_PROCESS_ERROR;
 }
 
 MSG_PROCESS_RETURN tls_process_certificate_request(SSL *s, PACKET *pkt)
 {
     int ret = MSG_PROCESS_ERROR;
-    unsigned int list_len, ctype_num, i, name_len;
+    unsigned int i, name_len;
     X509_NAME *xn = NULL;
-    const unsigned char *data;
     const unsigned char *namestart, *namebytes;
     STACK_OF(X509_NAME) *ca_sk = NULL;
+    PACKET cadns;
 
     if ((ca_sk = sk_X509_NAME_new(ca_dn_cmp)) == NULL) {
         SSLerr(SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST, ERR_R_MALLOC_FAILURE);
         goto err;
     }
 
-    /* get the certificate types */
-    if (!PACKET_get_1(pkt, &ctype_num)
-        || !PACKET_get_bytes(pkt, &data, ctype_num)) {
-        ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
-        SSLerr(SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST, SSL_R_LENGTH_MISMATCH);
-        goto err;
-    }
-    OPENSSL_free(s->cert->ctypes);
-    s->cert->ctypes = NULL;
-    if (ctype_num > SSL3_CT_NUMBER) {
-        /* If we exceed static buffer copy all to cert structure */
-        s->cert->ctypes = OPENSSL_malloc(ctype_num);
-        if (s->cert->ctypes == NULL) {
-            SSLerr(SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST, ERR_R_MALLOC_FAILURE);
+    if (SSL_IS_TLS13(s)) {
+        PACKET reqctx;
+
+        /* Free and zero certificate types: it is not present in TLS 1.3 */
+        OPENSSL_free(s->s3->tmp.ctype);
+        s->s3->tmp.ctype = NULL;
+        s->s3->tmp.ctype_len = 0;
+        /* TODO(TLS1.3) need to process request context, for now ignore */
+        if (!PACKET_get_length_prefixed_1(pkt, &reqctx)) {
+            SSLerr(SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST,
+                   SSL_R_LENGTH_MISMATCH);
+            goto err;
+        }
+    } else {
+        PACKET ctypes;
+
+        /* get the certificate types */
+        if (!PACKET_get_length_prefixed_1(pkt, &ctypes)) {
+            ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
+            SSLerr(SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST,
+                   SSL_R_LENGTH_MISMATCH);
+            goto err;
+        }
+
+        if (!PACKET_memdup(&ctypes, &s->s3->tmp.ctype, &s->s3->tmp.ctype_len)) {
+            SSLerr(SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST, ERR_R_INTERNAL_ERROR);
             goto err;
         }
-        memcpy(s->cert->ctypes, data, ctype_num);
-        s->cert->ctype_num = ctype_num;
-        ctype_num = SSL3_CT_NUMBER;
     }
-    for (i = 0; i < ctype_num; i++)
-        s->s3->tmp.ctype[i] = data[i];
 
     if (SSL_USE_SIGALGS(s)) {
-        if (!PACKET_get_net_2(pkt, &list_len)
-            || !PACKET_get_bytes(pkt, &data, list_len)) {
+        PACKET sigalgs;
+
+        if (!PACKET_get_length_prefixed_2(pkt, &sigalgs)) {
             ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
             SSLerr(SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST,
                    SSL_R_LENGTH_MISMATCH);
             goto err;
         }
 
-        /* Clear certificate digests and validity flags */
-        for (i = 0; i < SSL_PKEY_NUM; i++) {
-            s->s3->tmp.md[i] = NULL;
+        /* Clear certificate validity flags */
+        for (i = 0; i < SSL_PKEY_NUM; i++)
             s->s3->tmp.valid_flags[i] = 0;
-        }
-        if ((list_len & 1) || !tls1_save_sigalgs(s, data, list_len)) {
+        if (!tls1_save_sigalgs(s, &sigalgs)) {
             ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
             SSLerr(SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST,
                    SSL_R_SIGNATURE_ALGORITHMS_ERROR);
@@ -2026,21 +2261,18 @@ MSG_PROCESS_RETURN tls_process_certificate_request(SSL *s, PACKET *pkt)
             SSLerr(SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST, ERR_R_MALLOC_FAILURE);
             goto err;
         }
-    } else {
-        ssl_set_default_md(s);
     }
 
     /* get the CA RDNs */
-    if (!PACKET_get_net_2(pkt, &list_len)
-        || PACKET_remaining(pkt) != list_len) {
+    if (!PACKET_get_length_prefixed_2(pkt, &cadns)) {
         ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
         SSLerr(SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST, SSL_R_LENGTH_MISMATCH);
         goto err;
     }
 
-    while (PACKET_remaining(pkt)) {
-        if (!PACKET_get_net_2(pkt, &name_len)
-            || !PACKET_get_bytes(pkt, &namebytes, name_len)) {
+    while (PACKET_remaining(&cadns)) {
+        if (!PACKET_get_net_2(&cadns, &name_len)
+            || !PACKET_get_bytes(&cadns, &namebytes, name_len)) {
             ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
             SSLerr(SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST,
                    SSL_R_LENGTH_MISMATCH);
@@ -2068,10 +2300,26 @@ MSG_PROCESS_RETURN tls_process_certificate_request(SSL *s, PACKET *pkt)
         }
         xn = NULL;
     }
+    /* TODO(TLS1.3) need to parse and process extensions, for now ignore */
+    if (SSL_IS_TLS13(s)) {
+        PACKET reqexts;
+
+        if (!PACKET_get_length_prefixed_2(pkt, &reqexts)) {
+            ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
+            SSLerr(SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST,
+                   SSL_R_EXT_LENGTH_MISMATCH);
+            goto err;
+        }
+    }
+
+    if (PACKET_remaining(pkt) != 0) {
+        ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
+        SSLerr(SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST, SSL_R_LENGTH_MISMATCH);
+        goto err;
+    }
 
     /* we should setup a certificate to return.... */
     s->s3->tmp.cert_req = 1;
-    s->s3->tmp.ctype_num = ctype_num;
     sk_X509_NAME_pop_free(s->s3->tmp.ca_names, X509_NAME_free);
     s->s3->tmp.ca_names = ca_sk;
     ca_sk = NULL;
@@ -2093,23 +2341,31 @@ static int ca_dn_cmp(const X509_NAME *const *a, const X509_NAME *const *b)
 
 MSG_PROCESS_RETURN tls_process_new_session_ticket(SSL *s, PACKET *pkt)
 {
-    int al;
+    int al = SSL_AD_DECODE_ERROR;
     unsigned int ticklen;
-    unsigned long ticket_lifetime_hint;
+    unsigned long ticket_lifetime_hint, age_add = 0;
     unsigned int sess_len;
+    RAW_EXTENSION *exts = NULL;
 
     if (!PACKET_get_net_4(pkt, &ticket_lifetime_hint)
+        || (SSL_IS_TLS13(s) && !PACKET_get_net_4(pkt, &age_add))
         || !PACKET_get_net_2(pkt, &ticklen)
-        || PACKET_remaining(pkt) != ticklen) {
-        al = SSL_AD_DECODE_ERROR;
+        || (!SSL_IS_TLS13(s) && PACKET_remaining(pkt) != ticklen)
+        || (SSL_IS_TLS13(s)
+            && (ticklen == 0 || PACKET_remaining(pkt) < ticklen))) {
         SSLerr(SSL_F_TLS_PROCESS_NEW_SESSION_TICKET, SSL_R_LENGTH_MISMATCH);
         goto f_err;
     }
 
-    /* Server is allowed to change its mind and send an empty ticket. */
+    /*
+     * Server is allowed to change its mind (in <=TLSv1.2) and send an empty
+     * ticket. We already checked this TLSv1.3 case above, so it should never
+     * be 0 here in that instance
+     */
     if (ticklen == 0)
         return MSG_PROCESS_CONTINUE_READING;
 
+    /* TODO(TLS1.3): Is this a suitable test for TLS1.3? */
     if (s->session->session_id_length > 0) {
         int i = s->session_ctx->session_cache_mode;
         SSL_SESSION *new_sess;
@@ -2134,6 +2390,12 @@ MSG_PROCESS_RETURN tls_process_new_session_ticket(SSL *s, PACKET *pkt)
         s->session = new_sess;
     }
 
+    /*
+     * Technically the cast to long here is not guaranteed by the C standard -
+     * but we use it elsewhere, so this should be ok.
+     */
+    s->session->time = (long)time(NULL);
+
     OPENSSL_free(s->session->ext.tick);
     s->session->ext.tick = NULL;
     s->session->ext.ticklen = 0;
@@ -2150,7 +2412,23 @@ MSG_PROCESS_RETURN tls_process_new_session_ticket(SSL *s, PACKET *pkt)
     }
 
     s->session->ext.tick_lifetime_hint = ticket_lifetime_hint;
+    s->session->ext.tick_age_add = age_add;
     s->session->ext.ticklen = ticklen;
+
+    if (SSL_IS_TLS13(s)) {
+        PACKET extpkt;
+
+        if (!PACKET_as_length_prefixed_2(pkt, &extpkt)
+                || !tls_collect_extensions(s, &extpkt,
+                                           EXT_TLS1_3_NEW_SESSION_TICKET,
+                                           &exts, &al, NULL)
+                || !tls_parse_all_extensions(s, EXT_TLS1_3_NEW_SESSION_TICKET,
+                                             exts, NULL, 0, &al)) {
+            SSLerr(SSL_F_TLS_PROCESS_NEW_SESSION_TICKET, SSL_R_BAD_EXTENSION);
+            goto f_err;
+        }
+    }
+
     /*
      * There are two ways to detect a resumed ticket session. One is to set
      * an appropriate session ID and then the server must return a match in
@@ -2173,11 +2451,20 @@ MSG_PROCESS_RETURN tls_process_new_session_ticket(SSL *s, PACKET *pkt)
         goto err;
     }
     s->session->session_id_length = sess_len;
+
+    /* This is a standalone message in TLSv1.3, so there is no more to read */
+    if (SSL_IS_TLS13(s)) {
+        OPENSSL_free(exts);
+        ssl_update_cache(s, SSL_SESS_CACHE_CLIENT);
+        return MSG_PROCESS_FINISHED_READING;
+    }
+
     return MSG_PROCESS_CONTINUE_READING;
  f_err:
     ssl3_send_alert(s, SSL3_AL_FATAL, al);
  err:
     ossl_statem_set_error(s);
+    OPENSSL_free(exts);
     return MSG_PROCESS_ERROR;
 }
 
@@ -2219,7 +2506,7 @@ int tls_process_cert_status_body(SSL *s, PACKET *pkt, int *al)
 
     return 1;
 }
-    
+
 
 MSG_PROCESS_RETURN tls_process_cert_status(SSL *s, PACKET *pkt)
 {
@@ -2467,12 +2754,6 @@ static int tls_construct_cke_rsa(SSL *s, WPACKET *pkt, int *al)
     }
     EVP_PKEY_CTX_free(pctx);
     pctx = NULL;
-# ifdef PKCS1_CHECK
-    if (s->options & SSL_OP_PKCS1_CHECK_1)
-        (*p)[1]++;
-    if (s->options & SSL_OP_PKCS1_CHECK_2)
-        tmp_buf[0] = 0x70;
-# endif
 
     /* Fix buf for TLS and beyond */
     if (s->version > SSL3_VERSION && !WPACKET_close(pkt)) {
@@ -2483,6 +2764,10 @@ static int tls_construct_cke_rsa(SSL *s, WPACKET *pkt, int *al)
     s->s3->tmp.pms = pms;
     s->s3->tmp.pmslen = pmslen;
 
+    /* Log the premaster secret, if logging is enabled. */
+    if (!ssl_log_rsa_client_key_exchange(s, encdata, enclen, pms, pmslen))
+        goto err;
+
     return 1;
  err:
     OPENSSL_clear_free(pms, pmslen);
@@ -2847,10 +3132,8 @@ int tls_client_key_exchange_post_work(SSL *s)
  */
 static int ssl3_check_client_certificate(SSL *s)
 {
-    if (!s->cert || !s->cert->key->x509 || !s->cert->key->privatekey)
-        return 0;
     /* If no suitable signature algorithm can't use certificate */
-    if (SSL_USE_SIGALGS(s) && !s->s3->tmp.md[s->cert->key - s->cert->pkeys])
+    if (!tls_choose_sigalg(s, NULL) || s->s3->tmp.sigalg == NULL)
         return 0;
     /*
      * If strict mode check suitability of chain before using it. This also
@@ -3057,6 +3340,31 @@ int tls_construct_next_proto(SSL *s, WPACKET *pkt)
 }
 #endif
 
+MSG_PROCESS_RETURN tls_process_hello_req(SSL *s, PACKET *pkt)
+{
+    if (PACKET_remaining(pkt) > 0) {
+        /* should contain no data */
+        SSLerr(SSL_F_TLS_PROCESS_HELLO_REQ, SSL_R_LENGTH_MISMATCH);
+        ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
+        ossl_statem_set_error(s);
+        return MSG_PROCESS_ERROR;
+    }
+
+    /*
+     * This is a historical discrepancy (not in the RFC) maintained for
+     * compatibility reasons. If a TLS client receives a HelloRequest it will
+     * attempt an abbreviated handshake. However if a DTLS client receives a
+     * HelloRequest it will do a full handshake. Either behaviour is reasonable
+     * but doing one for TLS and another for DTLS is odd.
+     */
+    if (SSL_IS_DTLS(s))
+        SSL_renegotiate(s);
+    else
+        SSL_renegotiate_abbreviated(s);
+
+    return MSG_PROCESS_FINISHED_READING;
+}
+
 static MSG_PROCESS_RETURN tls_process_encrypted_extensions(SSL *s, PACKET *pkt)
 {
     int al = SSL_AD_INTERNAL_ERROR;
@@ -3070,7 +3378,7 @@ static MSG_PROCESS_RETURN tls_process_encrypted_extensions(SSL *s, PACKET *pkt)
     }
 
     if (!tls_collect_extensions(s, &extensions, EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
-                                &rawexts, &al)
+                                &rawexts, &al, NULL)
             || !tls_parse_all_extensions(s, EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
                                          rawexts, NULL, 0, &al))
         goto err;