Use stateful tickets if we are doing anti-replay
[openssl.git] / ssl / statem / statem_srvr.c
index c6a9a66781c25cb1d31e3a6091699f0f62758c24..9c44be0301c1f6c42627d6d5be28cbf101c8207f 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
  * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved
  * Copyright 2005 Nokia. All rights reserved.
  *
@@ -13,6 +13,7 @@
 #include "../ssl_locl.h"
 #include "statem_locl.h"
 #include "internal/constant_time_locl.h"
+#include "internal/cryptlib.h"
 #include <openssl/buffer.h>
 #include <openssl/rand.h>
 #include <openssl/objects.h>
@@ -23,6 +24,8 @@
 #include <openssl/bn.h>
 #include <openssl/md5.h>
 
+#define TICKET_NONCE_SIZE       8
+
 static int tls_construct_encrypted_extensions(SSL *s, WPACKET *pkt);
 
 /*
@@ -106,6 +109,13 @@ static int ossl_statem_server13_read_transition(SSL *s, int mt)
          */
         if (s->early_data_state == SSL_EARLY_DATA_READING)
             break;
+
+        if (mt == SSL3_MT_CERTIFICATE
+                && s->post_handshake_auth == SSL_PHA_REQUESTED) {
+            st->hand_state = TLS_ST_SR_CERT;
+            return 1;
+        }
+
         if (mt == SSL3_MT_KEY_UPDATE) {
             st->hand_state = TLS_ST_SR_KEY_UPDATE;
             return 1;
@@ -269,6 +279,20 @@ int ossl_statem_server_read_transition(SSL *s, int mt)
 
  err:
     /* No valid transition found */
+    if (SSL_IS_DTLS(s) && mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
+        BIO *rbio;
+
+        /*
+         * CCS messages don't have a message sequence number so this is probably
+         * because of an out-of-order CCS. We'll just drop it.
+         */
+        s->init_num = 0;
+        s->rwstate = SSL_READING;
+        rbio = SSL_get_rbio(s);
+        BIO_clear_retry_flags(rbio);
+        BIO_set_retry_read(rbio);
+        return 0;
+    }
     SSLfatal(s, SSL3_AD_UNEXPECTED_MESSAGE,
              SSL_F_OSSL_STATEM_SERVER_READ_TRANSITION,
              SSL_R_UNEXPECTED_MESSAGE);
@@ -324,16 +348,22 @@ static int send_server_key_exchange(SSL *s)
  *   1: Yes
  *   0: No
  */
-static int send_certificate_request(SSL *s)
+int send_certificate_request(SSL *s)
 {
     if (
            /* don't request cert unless asked for it: */
            s->verify_mode & SSL_VERIFY_PEER
+           /*
+            * don't request if post-handshake-only unless doing
+            * post-handshake in TLSv1.3:
+            */
+           && (!SSL_IS_TLS13(s) || !(s->verify_mode & SSL_VERIFY_POST_HANDSHAKE)
+               || s->post_handshake_auth == SSL_PHA_REQUEST_PENDING)
            /*
             * if SSL_VERIFY_CLIENT_ONCE is set, don't request cert
-            * during re-negotiation:
+            * a second time:
             */
-           && (s->s3->tmp.finish_md_len == 0 ||
+           && (s->certreqs_sent < 1 ||
                !(s->verify_mode & SSL_VERIFY_CLIENT_ONCE))
            /*
             * never request cert in anonymous ciphersuites (see
@@ -387,6 +417,10 @@ static WRITE_TRAN ossl_statem_server13_write_transition(SSL *s)
             st->hand_state = TLS_ST_SW_KEY_UPDATE;
             return WRITE_TRAN_CONTINUE;
         }
+        if (s->post_handshake_auth == SSL_PHA_REQUEST_PENDING) {
+            st->hand_state = TLS_ST_SW_CERT_REQ;
+            return WRITE_TRAN_CONTINUE;
+        }
         /* Try to read from the client instead */
         return WRITE_TRAN_FINISHED;
 
@@ -422,7 +456,12 @@ static WRITE_TRAN ossl_statem_server13_write_transition(SSL *s)
         return WRITE_TRAN_CONTINUE;
 
     case TLS_ST_SW_CERT_REQ:
-        st->hand_state = TLS_ST_SW_CERT;
+        if (s->post_handshake_auth == SSL_PHA_REQUEST_PENDING) {
+            s->post_handshake_auth = SSL_PHA_REQUESTED;
+            st->hand_state = TLS_ST_OK;
+        } else {
+            st->hand_state = TLS_ST_SW_CERT;
+        }
         return WRITE_TRAN_CONTINUE;
 
     case TLS_ST_SW_CERT:
@@ -443,13 +482,23 @@ static WRITE_TRAN ossl_statem_server13_write_transition(SSL *s)
     case TLS_ST_SR_FINISHED:
         /*
          * Technically we have finished the handshake at this point, but we're
-         * going to remain "in_init" for now and write out the session ticket
+         * going to remain "in_init" for now and write out any session tickets
          * immediately.
-         * TODO(TLS1.3): Perhaps we need to be able to control this behaviour
-         * and give the application the opportunity to delay sending the
-         * session ticket?
          */
-        st->hand_state = TLS_ST_SW_SESSION_TICKET;
+        if (s->post_handshake_auth == SSL_PHA_REQUESTED) {
+            s->post_handshake_auth = SSL_PHA_EXT_RECEIVED;
+        } else if (!s->ext.ticket_expected) {
+            /*
+             * If we're not going to renew the ticket then we just finish the
+             * handshake at this point.
+             */
+            st->hand_state = TLS_ST_OK;
+            return WRITE_TRAN_CONTINUE;
+        }
+        if (s->num_tickets > s->sent_tickets)
+            st->hand_state = TLS_ST_SW_SESSION_TICKET;
+        else
+            st->hand_state = TLS_ST_OK;
         return WRITE_TRAN_CONTINUE;
 
     case TLS_ST_SR_KEY_UPDATE:
@@ -460,9 +509,19 @@ static WRITE_TRAN ossl_statem_server13_write_transition(SSL *s)
         /* Fall through */
 
     case TLS_ST_SW_KEY_UPDATE:
-    case TLS_ST_SW_SESSION_TICKET:
         st->hand_state = TLS_ST_OK;
         return WRITE_TRAN_CONTINUE;
+
+    case TLS_ST_SW_SESSION_TICKET:
+        /* In a resumption we only ever send a maximum of one new ticket.
+         * Following an initial handshake we send the number of tickets we have
+         * been configured for.
+         */
+        if (s->hit || s->num_tickets <= s->sent_tickets) {
+            /* We've written enough tickets out. */
+            st->hand_state = TLS_ST_OK;
+        }
+        return WRITE_TRAN_CONTINUE;
     }
 }
 
@@ -514,10 +573,15 @@ WRITE_TRAN ossl_statem_server_write_transition(SSL *s)
 
     case TLS_ST_SR_CLNT_HELLO:
         if (SSL_IS_DTLS(s) && !s->d1->cookie_verified
-            && (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE))
+            && (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE)) {
             st->hand_state = DTLS_ST_SW_HELLO_VERIFY_REQUEST;
-        else
+        } else if (s->renegotiate == 0 && !SSL_IS_FIRST_HANDSHAKE(s)) {
+            /* We must have rejected the renegotiation */
+            st->hand_state = TLS_ST_OK;
+            return WRITE_TRAN_CONTINUE;
+        } else {
             st->hand_state = TLS_ST_SW_SRVR_HELLO;
+        }
         return WRITE_TRAN_CONTINUE;
 
     case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
@@ -649,7 +713,7 @@ WORK_STATE ossl_statem_server_pre_work(SSL *s, WORK_STATE wst)
         return WORK_FINISHED_CONTINUE;
 
     case TLS_ST_SW_SESSION_TICKET:
-        if (SSL_IS_TLS13(s)) {
+        if (SSL_IS_TLS13(s) && s->sent_tickets == 0) {
             /*
              * Actually this is the end of the handshake, but we're going
              * straight into writing the session ticket out. So we finish off
@@ -657,7 +721,7 @@ WORK_STATE ossl_statem_server_pre_work(SSL *s, WORK_STATE wst)
              *
              * Calls SSLfatal as required.
              */
-            return tls_finish_handshake(s, wst, 0);
+            return tls_finish_handshake(s, wst, 0, 0);
         } if (SSL_IS_DTLS(s)) {
             /*
              * We're into the last flight. We don't retransmit the last flight
@@ -687,13 +751,14 @@ WORK_STATE ossl_statem_server_pre_work(SSL *s, WORK_STATE wst)
         return WORK_FINISHED_CONTINUE;
 
     case TLS_ST_EARLY_DATA:
-        if (s->early_data_state != SSL_EARLY_DATA_ACCEPTING)
+        if (s->early_data_state != SSL_EARLY_DATA_ACCEPTING
+                && (s->s3->flags & TLS1_FLAGS_STATELESS) == 0)
             return WORK_FINISHED_CONTINUE;
         /* Fall through */
 
     case TLS_ST_OK:
         /* Calls SSLfatal() as required */
-        return tls_finish_handshake(s, wst, 1);
+        return tls_finish_handshake(s, wst, 1, 1);
     }
 
     return WORK_FINISHED_CONTINUE;
@@ -856,6 +921,13 @@ WORK_STATE ossl_statem_server_post_work(SSL *s, WORK_STATE wst)
         }
         break;
 
+    case TLS_ST_SW_CERT_REQ:
+        if (s->post_handshake_auth == SSL_PHA_REQUEST_PENDING) {
+            if (statem_flush(s) != 1)
+                return WORK_MORE_A;
+        }
+        break;
+
     case TLS_ST_SW_KEY_UPDATE:
         if (statem_flush(s) != 1)
             return WORK_MORE_A;
@@ -1112,7 +1184,6 @@ WORK_STATE ossl_statem_server_post_process_message(SSL *s, WORK_STATE wst)
     case TLS_ST_SR_KEY_EXCH:
         return tls_post_process_client_key_exchange(s, wst);
     }
-    return WORK_FINISHED_CONTINUE;
 }
 
 #ifndef OPENSSL_NO_SRP
@@ -1253,24 +1324,33 @@ MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
     /* |cookie| will only be initialized for DTLS. */
     PACKET session_id, compression, extensions, cookie;
     static const unsigned char null_compression = 0;
-    CLIENTHELLO_MSG *clienthello;
+    CLIENTHELLO_MSG *clienthello = NULL;
 
-    clienthello = OPENSSL_zalloc(sizeof(*clienthello));
-    if (clienthello == NULL) {
-        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO,
-                 ERR_R_INTERNAL_ERROR);
-        goto err;
-    }
     /* Check if this is actually an unexpected renegotiation ClientHello */
     if (s->renegotiate == 0 && !SSL_IS_FIRST_HANDSHAKE(s)) {
-        if ((s->options & SSL_OP_NO_RENEGOTIATION)) {
-            ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
+        if (!ossl_assert(!SSL_IS_TLS13(s))) {
+            SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO,
+                     ERR_R_INTERNAL_ERROR);
             goto err;
         }
+        if ((s->options & SSL_OP_NO_RENEGOTIATION) != 0
+                || (!s->s3->send_connection_binding
+                    && (s->options
+                        & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION) == 0)) {
+            ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
+            return MSG_PROCESS_FINISHED_READING;
+        }
         s->renegotiate = 1;
         s->new_session = 1;
     }
 
+    clienthello = OPENSSL_zalloc(sizeof(*clienthello));
+    if (clienthello == NULL) {
+        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO,
+                 ERR_R_INTERNAL_ERROR);
+        goto err;
+    }
+
     /*
      * First, parse the raw ClientHello data into the CLIENTHELLO_MSG structure.
      */
@@ -2054,7 +2134,17 @@ int tls_handle_alpn(SSL *s)
                 s->ext.early_data_ok = 0;
 
                 if (!s->hit) {
-                    /* If a new session update it with the new ALPN value */
+                    /*
+                     * This is a new session and so alpn_selected should have
+                     * been initialised to NULL. We should update it with the
+                     * selected ALPN.
+                     */
+                    if (!ossl_assert(s->session->ext.alpn_selected == NULL)) {
+                        SSLfatal(s, SSL_AD_INTERNAL_ERROR,
+                                 SSL_F_TLS_HANDLE_ALPN,
+                                 ERR_R_INTERNAL_ERROR);
+                        return 0;
+                    }
                     s->session->ext.alpn_selected = OPENSSL_memdup(selected,
                                                                    selected_len);
                     if (s->session->ext.alpn_selected == NULL) {
@@ -2303,7 +2393,7 @@ int tls_construct_server_hello(SSL *s, WPACKET *pkt)
          * Re-initialise the Transcript Hash. We're going to prepopulate it with
          * a synthetic message_hash in place of ClientHello1.
          */
-        if (!create_synthetic_message_hash(s)) {
+        if (!create_synthetic_message_hash(s, NULL, 0, NULL, 0)) {
             /* SSLfatal() already called */
             return 0;
         }
@@ -2425,6 +2515,12 @@ int tls_construct_server_key_exchange(SSL *s, WPACKET *pkt)
         }
 
         dh = EVP_PKEY_get0_DH(s->s3->tmp.pkey);
+        if (dh == NULL) {
+            SSLfatal(s, SSL_AD_INTERNAL_ERROR,
+                     SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
+                     ERR_R_INTERNAL_ERROR);
+            goto err;
+        }
 
         EVP_PKEY_free(pkdh);
         pkdh = NULL;
@@ -2686,12 +2782,30 @@ int tls_construct_server_key_exchange(SSL *s, WPACKET *pkt)
 int tls_construct_certificate_request(SSL *s, WPACKET *pkt)
 {
     if (SSL_IS_TLS13(s)) {
-        /* TODO(TLS1.3) for now send empty request context */
-        if (!WPACKET_put_bytes_u8(pkt, 0)) {
-            SSLfatal(s, SSL_AD_INTERNAL_ERROR,
-                     SSL_F_TLS_CONSTRUCT_CERTIFICATE_REQUEST,
-                     ERR_R_INTERNAL_ERROR);
-            return 0;
+        /* Send random context when doing post-handshake auth */
+        if (s->post_handshake_auth == SSL_PHA_REQUEST_PENDING) {
+            OPENSSL_free(s->pha_context);
+            s->pha_context_len = 32;
+            if ((s->pha_context = OPENSSL_malloc(s->pha_context_len)) == NULL
+                    || RAND_bytes(s->pha_context, s->pha_context_len) <= 0
+                    || !WPACKET_sub_memcpy_u8(pkt, s->pha_context, s->pha_context_len)) {
+                SSLfatal(s, SSL_AD_INTERNAL_ERROR,
+                         SSL_F_TLS_CONSTRUCT_CERTIFICATE_REQUEST,
+                         ERR_R_INTERNAL_ERROR);
+                return 0;
+            }
+            /* reset the handshake hash back to just after the ClientFinished */
+            if (!tls13_restore_handshake_digest_for_pha(s)) {
+                /* SSLfatal() already called */
+                return 0;
+            }
+        } else {
+            if (!WPACKET_put_bytes_u8(pkt, 0)) {
+                SSLfatal(s, SSL_AD_INTERNAL_ERROR,
+                         SSL_F_TLS_CONSTRUCT_CERTIFICATE_REQUEST,
+                         ERR_R_INTERNAL_ERROR);
+                return 0;
+            }
         }
 
         if (!tls_construct_extensions(s, pkt,
@@ -2732,6 +2846,7 @@ int tls_construct_certificate_request(SSL *s, WPACKET *pkt)
     }
 
  done:
+    s->certreqs_sent++;
     s->s3->tmp.cert_request = 1;
     return 1;
 }
@@ -2861,7 +2976,7 @@ static int tls_process_cke_rsa(SSL *s, PACKET *pkt)
      * fails. See https://tools.ietf.org/html/rfc5246#section-7.4.7.1
      */
 
-    if (ssl_randbytes(s, rand_premaster_secret,
+    if (RAND_priv_bytes(rand_premaster_secret,
                       sizeof(rand_premaster_secret)) <= 0) {
         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_RSA,
                  ERR_R_INTERNAL_ERROR);
@@ -3158,11 +3273,9 @@ static int tls_process_cke_gost(SSL *s, PACKET *pkt)
     const unsigned char *start;
     size_t outlen = 32, inlen;
     unsigned long alg_a;
-    int Ttag, Tclass;
-    long Tlen;
-    size_t sess_key_len;
-    const unsigned char *data;
+    unsigned int asn1id, asn1len;
     int ret = 0;
+    PACKET encdata;
 
     /* Get our certificate private key */
     alg_a = s->s3->tmp.new_cipher->algorithm_auth;
@@ -3204,22 +3317,42 @@ static int tls_process_cke_gost(SSL *s, PACKET *pkt)
             ERR_clear_error();
     }
     /* Decrypt session key */
-    sess_key_len = PACKET_remaining(pkt);
-    if (!PACKET_get_bytes(pkt, &data, sess_key_len)) {
-        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_GOST,
-                 ERR_R_INTERNAL_ERROR);
+    if (!PACKET_get_1(pkt, &asn1id)
+            || asn1id != (V_ASN1_SEQUENCE | V_ASN1_CONSTRUCTED)
+            || !PACKET_peek_1(pkt, &asn1len)) {
+        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_GOST,
+                 SSL_R_DECRYPTION_FAILED);
         goto err;
     }
-    /* TODO(size_t): Convert this function */
-    if (ASN1_get_object((const unsigned char **)&data, &Tlen, &Ttag,
-                        &Tclass, (long)sess_key_len) != V_ASN1_CONSTRUCTED
-        || Ttag != V_ASN1_SEQUENCE || Tclass != V_ASN1_UNIVERSAL) {
+    if (asn1len == 0x81) {
+        /*
+         * Long form length. Should only be one byte of length. Anything else
+         * isn't supported.
+         * We did a successful peek before so this shouldn't fail
+         */
+        if (!PACKET_forward(pkt, 1)) {
+            SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_GOST,
+                     SSL_R_DECRYPTION_FAILED);
+            goto err;
+        }
+    } else  if (asn1len >= 0x80) {
+        /*
+         * Indefinite length, or more than one long form length bytes. We don't
+         * support it
+         */
+        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_GOST,
+                 SSL_R_DECRYPTION_FAILED);
+        goto err;
+    } /* else short form length */
+
+    if (!PACKET_as_length_prefixed_1(pkt, &encdata)) {
         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_GOST,
                  SSL_R_DECRYPTION_FAILED);
         goto err;
     }
-    start = data;
-    inlen = Tlen;
+    inlen = PACKET_remaining(&encdata);
+    start = PACKET_data(&encdata);
+
     if (EVP_PKEY_decrypt(pkey_ctx, premaster_secret, &outlen, start,
                          inlen) <= 0) {
         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_GOST,
@@ -3380,11 +3513,12 @@ MSG_PROCESS_RETURN tls_process_client_certificate(SSL *s, PACKET *pkt)
     int i;
     MSG_PROCESS_RETURN ret = MSG_PROCESS_ERROR;
     X509 *x = NULL;
-    unsigned long l, llen;
+    unsigned long l;
     const unsigned char *certstart, *certbytes;
     STACK_OF(X509) *sk = NULL;
     PACKET spkt, context;
     size_t chainidx;
+    SSL_SESSION *new_sess = NULL;
 
     if ((sk = sk_X509_new_null()) == NULL) {
         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
@@ -3392,10 +3526,16 @@ MSG_PROCESS_RETURN tls_process_client_certificate(SSL *s, PACKET *pkt)
         goto err;
     }
 
-    /* TODO(TLS1.3): For now we ignore the context. We need to verify this */
-    if ((SSL_IS_TLS13(s) && !PACKET_get_length_prefixed_1(pkt, &context))
-            || !PACKET_get_net_3(pkt, &llen)
-            || !PACKET_get_sub_packet(pkt, &spkt, llen)
+    if (SSL_IS_TLS13(s) && (!PACKET_get_length_prefixed_1(pkt, &context)
+                            || (s->pha_context == NULL && PACKET_remaining(&context) != 0)
+                            || (s->pha_context != NULL &&
+                                !PACKET_equal(&context, s->pha_context, s->pha_context_len)))) {
+        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
+                 SSL_R_INVALID_CONTEXT);
+        goto err;
+    }
+
+    if (!PACKET_get_length_prefixed_3(pkt, &spkt)
             || PACKET_remaining(pkt) != 0) {
         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
                  SSL_R_LENGTH_MISMATCH);
@@ -3481,7 +3621,7 @@ MSG_PROCESS_RETURN tls_process_client_certificate(SSL *s, PACKET *pkt)
         EVP_PKEY *pkey;
         i = ssl_verify_cert_chain(s, sk);
         if (i <= 0) {
-            SSLfatal(s, ssl_verify_alarm_type(s->verify_result),
+            SSLfatal(s, ssl_x509err2alert(s->verify_result),
                      SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
                      SSL_R_CERTIFICATE_VERIFY_FAILED);
             goto err;
@@ -3500,6 +3640,35 @@ MSG_PROCESS_RETURN tls_process_client_certificate(SSL *s, PACKET *pkt)
         }
     }
 
+    /*
+     * Sessions must be immutable once they go into the session cache. Otherwise
+     * we can get multi-thread problems. Therefore we don't "update" sessions,
+     * we replace them with a duplicate. Here, we need to do this every time
+     * a new certificate is received via post-handshake authentication, as the
+     * session may have already gone into the session cache.
+     */
+
+    if (s->post_handshake_auth == SSL_PHA_REQUESTED) {
+        int m = s->session_ctx->session_cache_mode;
+
+        if ((new_sess = ssl_session_dup(s->session, 0)) == 0) {
+            SSLfatal(s, SSL_AD_INTERNAL_ERROR,
+                     SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
+                     ERR_R_MALLOC_FAILURE);
+            goto err;
+        }
+
+        if (m & SSL_SESS_CACHE_SERVER) {
+            /*
+             * Remove the old session from the cache. We carry on if this fails
+             */
+            SSL_CTX_remove_session(s->session_ctx, s->session);
+        }
+
+        SSL_SESSION_free(s->session);
+        s->session = new_sess;
+    }
+
     X509_free(s->session->peer);
     s->session->peer = sk_X509_shift(sk);
     s->session->verify_result = s->verify_result;
@@ -3523,12 +3692,16 @@ MSG_PROCESS_RETURN tls_process_client_certificate(SSL *s, PACKET *pkt)
     sk = 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)) {
-        /* SSLfatal() already called */
-        goto err;
+    if (SSL_IS_TLS13(s)) {
+        if (!ssl_handshake_hash(s, s->cert_verify_hash,
+                                sizeof(s->cert_verify_hash),
+                                &s->cert_verify_hash_len)) {
+            /* SSLfatal() already called */
+            goto err;
+        }
+
+        /* Resend session tickets */
+        s->sent_tickets = 0;
     }
 
     ret = MSG_PROCESS_CONTINUE_READING;
@@ -3566,7 +3739,44 @@ int tls_construct_server_certificate(SSL *s, WPACKET *pkt)
     return 1;
 }
 
-int tls_construct_new_session_ticket(SSL *s, WPACKET *pkt)
+static int create_ticket_prequel(SSL *s, WPACKET *pkt, uint32_t age_add,
+                                 unsigned char *tick_nonce)
+{
+    /*
+     * Ticket lifetime hint: For TLSv1.2 this is advisory only and we leave this
+     * unspecified for resumed session (for simplicity).
+     * In TLSv1.3 we reset the "time" field above, and always specify the
+     * timeout.
+     */
+    if (!WPACKET_put_bytes_u32(pkt,
+                               (s->hit && !SSL_IS_TLS13(s))
+                               ? 0 : s->session->timeout)) {
+        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_CREATE_TICKET_PREQUEL,
+                 ERR_R_INTERNAL_ERROR);
+        return 0;
+    }
+
+    if (SSL_IS_TLS13(s)) {
+        if (!WPACKET_put_bytes_u32(pkt, age_add)
+                || !WPACKET_sub_memcpy_u8(pkt, tick_nonce, TICKET_NONCE_SIZE)) {
+            SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_CREATE_TICKET_PREQUEL,
+                     ERR_R_INTERNAL_ERROR);
+            return 0;
+        }
+    }
+
+    /* Start the sub-packet for the actual ticket data */
+    if (!WPACKET_start_sub_packet_u16(pkt)) {
+        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_CREATE_TICKET_PREQUEL,
+                 ERR_R_INTERNAL_ERROR);
+        return 0;
+    }
+
+    return 1;
+}
+
+static int construct_stateless_ticket(SSL *s, WPACKET *pkt, uint32_t age_add,
+                                      unsigned char *tick_nonce)
 {
     unsigned char *senc = NULL;
     EVP_CIPHER_CTX *ctx = NULL;
@@ -3579,50 +3789,8 @@ int tls_construct_new_session_ticket(SSL *s, WPACKET *pkt)
     SSL_CTX *tctx = s->session_ctx;
     unsigned char iv[EVP_MAX_IV_LENGTH];
     unsigned char key_name[TLSEXT_KEYNAME_LENGTH];
-    int iv_len;
+    int iv_len, ok = 0;
     size_t macoffset, macendoffset;
-    union {
-        unsigned char age_add_c[sizeof(uint32_t)];
-        uint32_t age_add;
-    } age_add_u;
-
-    if (SSL_IS_TLS13(s)) {
-        if (ssl_randbytes(s, age_add_u.age_add_c, sizeof(age_add_u)) <= 0) {
-            SSLfatal(s, SSL_AD_INTERNAL_ERROR,
-                     SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET,
-                     ERR_R_INTERNAL_ERROR);
-            goto err;
-        }
-        s->session->ext.tick_age_add = age_add_u.age_add;
-       /*
-        * ticket_nonce is set to a single 0 byte because we only ever send a
-        * single ticket per connection. IMPORTANT: If we ever support multiple
-        * tickets per connection then this will need to be changed.
-        */
-        OPENSSL_free(s->session->ext.tick_nonce);
-        s->session->ext.tick_nonce = OPENSSL_zalloc(sizeof(char));
-        if (s->session->ext.tick_nonce == NULL) {
-            SSLfatal(s, SSL_AD_INTERNAL_ERROR,
-                     SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET,
-                     ERR_R_MALLOC_FAILURE);
-            goto err;
-        }
-        s->session->ext.tick_nonce_len = 1;
-        s->session->time = (long)time(NULL);
-        if (s->s3->alpn_selected != NULL) {
-            OPENSSL_free(s->session->ext.alpn_selected);
-            s->session->ext.alpn_selected =
-                OPENSSL_memdup(s->s3->alpn_selected, s->s3->alpn_selected_len);
-            if (s->session->ext.alpn_selected == NULL) {
-                SSLfatal(s, SSL_AD_INTERNAL_ERROR,
-                         SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET,
-                         ERR_R_MALLOC_FAILURE);
-                goto err;
-            }
-            s->session->ext.alpn_selected_len = s->s3->alpn_selected_len;
-        }
-        s->session->ext.max_early_data = s->max_early_data;
-    }
 
     /* get session encoding length */
     slen_full = i2d_SSL_SESSION(s->session, NULL);
@@ -3631,29 +3799,29 @@ int tls_construct_new_session_ticket(SSL *s, WPACKET *pkt)
      * long
      */
     if (slen_full == 0 || slen_full > 0xFF00) {
-        SSLfatal(s, SSL_AD_INTERNAL_ERROR,
-                 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR);
+        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_CONSTRUCT_STATELESS_TICKET,
+                 ERR_R_INTERNAL_ERROR);
         goto err;
     }
     senc = OPENSSL_malloc(slen_full);
     if (senc == NULL) {
         SSLfatal(s, SSL_AD_INTERNAL_ERROR,
-                 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_MALLOC_FAILURE);
+                 SSL_F_CONSTRUCT_STATELESS_TICKET, ERR_R_MALLOC_FAILURE);
         goto err;
     }
 
     ctx = EVP_CIPHER_CTX_new();
     hctx = HMAC_CTX_new();
     if (ctx == NULL || hctx == NULL) {
-        SSLfatal(s, SSL_AD_INTERNAL_ERROR,
-                 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_MALLOC_FAILURE);
+        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_CONSTRUCT_STATELESS_TICKET,
+                 ERR_R_MALLOC_FAILURE);
         goto err;
     }
 
     p = senc;
     if (!i2d_SSL_SESSION(s->session, &p)) {
-        SSLfatal(s, SSL_AD_INTERNAL_ERROR,
-                 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR);
+        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_CONSTRUCT_STATELESS_TICKET,
+                 ERR_R_INTERNAL_ERROR);
         goto err;
     }
 
@@ -3663,24 +3831,23 @@ int tls_construct_new_session_ticket(SSL *s, WPACKET *pkt)
     const_p = senc;
     sess = d2i_SSL_SESSION(NULL, &const_p, slen_full);
     if (sess == NULL) {
-        SSLfatal(s, SSL_AD_INTERNAL_ERROR,
-                 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR);
+        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_CONSTRUCT_STATELESS_TICKET,
+                 ERR_R_INTERNAL_ERROR);
         goto err;
     }
-    sess->session_id_length = 0; /* ID is irrelevant for the ticket */
 
     slen = i2d_SSL_SESSION(sess, NULL);
     if (slen == 0 || slen > slen_full) {
         /* shouldn't ever happen */
-        SSLfatal(s, SSL_AD_INTERNAL_ERROR,
-                 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR);
+        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_CONSTRUCT_STATELESS_TICKET,
+                 ERR_R_INTERNAL_ERROR);
         SSL_SESSION_free(sess);
         goto err;
     }
     p = senc;
     if (!i2d_SSL_SESSION(sess, &p)) {
-        SSLfatal(s, SSL_AD_INTERNAL_ERROR,
-                 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR);
+        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_CONSTRUCT_STATELESS_TICKET,
+                 ERR_R_INTERNAL_ERROR);
         SSL_SESSION_free(sess);
         goto err;
     }
@@ -3701,7 +3868,7 @@ int tls_construct_new_session_ticket(SSL *s, WPACKET *pkt)
             if (!WPACKET_put_bytes_u32(pkt, 0)
                     || !WPACKET_put_bytes_u16(pkt, 0)) {
                 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
-                         SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET,
+                         SSL_F_CONSTRUCT_STATELESS_TICKET,
                          ERR_R_INTERNAL_ERROR);
                 goto err;
             }
@@ -3711,8 +3878,7 @@ int tls_construct_new_session_ticket(SSL *s, WPACKET *pkt)
             return 1;
         }
         if (ret < 0) {
-            SSLfatal(s, SSL_AD_INTERNAL_ERROR,
-                     SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET,
+            SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_CONSTRUCT_STATELESS_TICKET,
                      SSL_R_CALLBACK_FAILED);
             goto err;
         }
@@ -3721,14 +3887,13 @@ int tls_construct_new_session_ticket(SSL *s, WPACKET *pkt)
         const EVP_CIPHER *cipher = EVP_aes_256_cbc();
 
         iv_len = EVP_CIPHER_iv_length(cipher);
-        if (ssl_randbytes(s, iv, iv_len) <= 0
+        if (RAND_bytes(iv, iv_len) <= 0
                 || !EVP_EncryptInit_ex(ctx, cipher, NULL,
-                                       tctx->ext.tick_aes_key, iv)
-                || !HMAC_Init_ex(hctx, tctx->ext.tick_hmac_key,
-                                 sizeof(tctx->ext.tick_hmac_key),
+                                       tctx->ext.secure->tick_aes_key, iv)
+                || !HMAC_Init_ex(hctx, tctx->ext.secure->tick_hmac_key,
+                                 sizeof(tctx->ext.secure->tick_hmac_key),
                                  EVP_sha256(), NULL)) {
-            SSLfatal(s, SSL_AD_INTERNAL_ERROR,
-                     SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET,
+            SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_CONSTRUCT_STATELESS_TICKET,
                      ERR_R_INTERNAL_ERROR);
             goto err;
         }
@@ -3736,22 +3901,12 @@ int tls_construct_new_session_ticket(SSL *s, WPACKET *pkt)
                sizeof(tctx->ext.tick_key_name));
     }
 
-    /*
-     * Ticket lifetime hint: For TLSv1.2 this is advisory only and we leave this
-     * unspecified for resumed session (for simplicity).
-     * In TLSv1.3 we reset the "time" field above, and always specify the
-     * timeout.
-     */
-    if (!WPACKET_put_bytes_u32(pkt,
-                               (s->hit && !SSL_IS_TLS13(s))
-                               ? 0 : s->session->timeout)
-            || (SSL_IS_TLS13(s)
-                && (!WPACKET_put_bytes_u32(pkt, age_add_u.age_add)
-                    || !WPACKET_sub_memcpy_u8(pkt, s->session->ext.tick_nonce,
-                                              s->session->ext.tick_nonce_len)))
-               /* Now the actual ticket data */
-            || !WPACKET_start_sub_packet_u16(pkt)
-            || !WPACKET_get_total_written(pkt, &macoffset)
+    if (!create_ticket_prequel(s, pkt, age_add, tick_nonce)) {
+        /* SSLfatal() already called */
+        goto err;
+    }
+
+    if (!WPACKET_get_total_written(pkt, &macoffset)
                /* Output key name */
             || !WPACKET_memcpy(pkt, key_name, sizeof(key_name))
                /* output IV */
@@ -3774,28 +3929,195 @@ int tls_construct_new_session_ticket(SSL *s, WPACKET *pkt)
             || !HMAC_Final(hctx, macdata1, &hlen)
             || hlen > EVP_MAX_MD_SIZE
             || !WPACKET_allocate_bytes(pkt, hlen, &macdata2)
-            || macdata1 != macdata2
-            || !WPACKET_close(pkt)) {
+            || macdata1 != macdata2) {
         SSLfatal(s, SSL_AD_INTERNAL_ERROR,
-                 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR);
+                 SSL_F_CONSTRUCT_STATELESS_TICKET, ERR_R_INTERNAL_ERROR);
         goto err;
     }
-    if (SSL_IS_TLS13(s)
-            && !tls_construct_extensions(s, pkt,
-                                         SSL_EXT_TLS1_3_NEW_SESSION_TICKET,
-                                         NULL, 0)) {
-        /* SSLfatal() already called */
+
+    /* Close the sub-packet created by create_ticket_prequel() */
+    if (!WPACKET_close(pkt)) {
+        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_CONSTRUCT_STATELESS_TICKET,
+                 ERR_R_INTERNAL_ERROR);
         goto err;
     }
-    EVP_CIPHER_CTX_free(ctx);
-    HMAC_CTX_free(hctx);
-    OPENSSL_free(senc);
 
-    return 1;
+    ok = 1;
  err:
     OPENSSL_free(senc);
     EVP_CIPHER_CTX_free(ctx);
     HMAC_CTX_free(hctx);
+    return ok;
+}
+
+static int construct_stateful_ticket(SSL *s, WPACKET *pkt, uint32_t age_add,
+                                     unsigned char *tick_nonce)
+{
+    if (!create_ticket_prequel(s, pkt, age_add, tick_nonce)) {
+        /* SSLfatal() already called */
+        return 0;
+    }
+
+    if (!WPACKET_memcpy(pkt, s->session->session_id,
+                        s->session->session_id_length)
+            || !WPACKET_close(pkt)) {
+        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_CONSTRUCT_STATEFUL_TICKET,
+                 ERR_R_INTERNAL_ERROR);
+        return 0;
+    }
+
+    return 1;
+}
+
+int tls_construct_new_session_ticket(SSL *s, WPACKET *pkt)
+{
+    SSL_CTX *tctx = s->session_ctx;
+    unsigned char tick_nonce[TICKET_NONCE_SIZE];
+    union {
+        unsigned char age_add_c[sizeof(uint32_t)];
+        uint32_t age_add;
+    } age_add_u;
+
+    age_add_u.age_add = 0;
+
+    if (SSL_IS_TLS13(s)) {
+        size_t i, hashlen;
+        uint64_t nonce;
+        static const unsigned char nonce_label[] = "resumption";
+        const EVP_MD *md = ssl_handshake_md(s);
+        void (*cb) (const SSL *ssl, int type, int val) = NULL;
+        int hashleni = EVP_MD_size(md);
+
+        /* Ensure cast to size_t is safe */
+        if (!ossl_assert(hashleni >= 0)) {
+            SSLfatal(s, SSL_AD_INTERNAL_ERROR,
+                     SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET,
+                     ERR_R_INTERNAL_ERROR);
+            goto err;
+        }
+        hashlen = (size_t)hashleni;
+
+        if (s->info_callback != NULL)
+            cb = s->info_callback;
+        else if (s->ctx->info_callback != NULL)
+            cb = s->ctx->info_callback;
+
+        if (cb != NULL) {
+            /*
+             * We don't start and stop the handshake in between each ticket when
+             * sending more than one - but it should appear that way to the info
+             * callback.
+             */
+            if (s->sent_tickets != 0) {
+                ossl_statem_set_in_init(s, 0);
+                cb(s, SSL_CB_HANDSHAKE_DONE, 1);
+                ossl_statem_set_in_init(s, 1);
+            }
+            cb(s, SSL_CB_HANDSHAKE_START, 1);
+        }
+        /*
+         * If we already sent one NewSessionTicket, or we resumed then
+         * s->session may already be in a cache and so we must not modify it.
+         * Instead we need to take a copy of it and modify that.
+         */
+        if (s->sent_tickets != 0 || s->hit) {
+            SSL_SESSION *new_sess = ssl_session_dup(s->session, 0);
+
+            if (new_sess == NULL) {
+                /* SSLfatal already called */
+                goto err;
+            }
+
+            SSL_SESSION_free(s->session);
+            s->session = new_sess;
+        }
+
+        if (!ssl_generate_session_id(s, s->session)) {
+            /* SSLfatal() already called */
+            goto err;
+        }
+        if (RAND_bytes(age_add_u.age_add_c, sizeof(age_add_u)) <= 0) {
+            SSLfatal(s, SSL_AD_INTERNAL_ERROR,
+                     SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET,
+                     ERR_R_INTERNAL_ERROR);
+            goto err;
+        }
+        s->session->ext.tick_age_add = age_add_u.age_add;
+
+        nonce = s->next_ticket_nonce;
+        for (i = TICKET_NONCE_SIZE; i > 0; i--) {
+            tick_nonce[i - 1] = (unsigned char)(nonce & 0xff);
+            nonce >>= 8;
+        }
+
+        if (!tls13_hkdf_expand(s, md, s->resumption_master_secret,
+                               nonce_label,
+                               sizeof(nonce_label) - 1,
+                               tick_nonce,
+                               TICKET_NONCE_SIZE,
+                               s->session->master_key,
+                               hashlen)) {
+            /* SSLfatal() already called */
+            goto err;
+        }
+        s->session->master_key_length = hashlen;
+
+        s->session->time = (long)time(NULL);
+        if (s->s3->alpn_selected != NULL) {
+            OPENSSL_free(s->session->ext.alpn_selected);
+            s->session->ext.alpn_selected =
+                OPENSSL_memdup(s->s3->alpn_selected, s->s3->alpn_selected_len);
+            if (s->session->ext.alpn_selected == NULL) {
+                SSLfatal(s, SSL_AD_INTERNAL_ERROR,
+                         SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET,
+                         ERR_R_MALLOC_FAILURE);
+                goto err;
+            }
+            s->session->ext.alpn_selected_len = s->s3->alpn_selected_len;
+        }
+        s->session->ext.max_early_data = s->max_early_data;
+    }
+
+    if (tctx->generate_ticket_cb != NULL &&
+        tctx->generate_ticket_cb(s, tctx->ticket_cb_data) == 0)
+        goto err;
+
+    /*
+     * If we are using anti-replay protection then we behave as if
+     * SSL_OP_NO_TICKET is set - we are caching tickets anyway so there
+     * is no point in using full stateless tickets.
+     */
+    if (((s->options & SSL_OP_NO_TICKET) != 0 || s->max_early_data > 0)
+            && SSL_IS_TLS13(s)) {
+        if (!construct_stateful_ticket(s, pkt, age_add_u.age_add, tick_nonce)) {
+            /* SSLfatal() already called */
+            goto err;
+        }
+    } else if (!construct_stateless_ticket(s, pkt, age_add_u.age_add,
+                                           tick_nonce)) {
+        /* SSLfatal() already called */
+        goto err;
+    }
+
+    if (SSL_IS_TLS13(s)) {
+        if (!tls_construct_extensions(s, pkt,
+                                      SSL_EXT_TLS1_3_NEW_SESSION_TICKET,
+                                      NULL, 0)) {
+            /* SSLfatal() already called */
+            goto err;
+        }
+        /*
+         * Increment both |sent_tickets| and |next_ticket_nonce|. |sent_tickets|
+         * gets reset to 0 if we send more tickets following a post-handshake
+         * auth, but |next_ticket_nonce| does not.
+         */
+        s->sent_tickets++;
+        s->next_ticket_nonce++;
+        ssl_update_cache(s, SSL_SESS_CACHE_SERVER);
+    }
+
+    return 1;
+ err:
     return 0;
 }