Add m-esr52 at 52.6.0

1 files changed, 4512 insertions, 0 deletions

diff --git a/security/nss/lib/ssl/tls13con.c b/security/nss/lib/ssl/tls13con.c
new file mode 100644
index 000000000..c6a584748
--- /dev/null
+++ b/security/nss/lib/ssl/tls13con.c
@@ -0,0 +1,4512 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * TLS 1.3 Protocol
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "stdarg.h"
+#include "cert.h"
+#include "ssl.h"
+#include "keyhi.h"
+#include "pk11func.h"
+#include "prerr.h"
+#include "secitem.h"
+#include "secmod.h"
+#include "sslimpl.h"
+#include "sslproto.h"
+#include "sslerr.h"
+#include "tls13hkdf.h"
+#include "tls13con.h"
+#include "tls13exthandle.h"
+
+typedef enum {
+    TrafficKeyEarlyApplicationData,
+    TrafficKeyHandshake,
+    TrafficKeyApplicationData
+} TrafficKeyType;
+
+typedef enum {
+    CipherSpecRead,
+    CipherSpecWrite,
+} CipherSpecDirection;
+
+static SECStatus tls13_SetCipherSpec(sslSocket *ss, TrafficKeyType type,
+                                     CipherSpecDirection install,
+                                     PRBool deleteSecret);
+static SECStatus tls13_AESGCM(
+    ssl3KeyMaterial *keys,
+    PRBool doDecrypt,
+    unsigned char *out, int *outlen, int maxout,
+    const unsigned char *in, int inlen,
+    const unsigned char *additionalData, int additionalDataLen);
+static SECStatus tls13_ChaCha20Poly1305(
+    ssl3KeyMaterial *keys,
+    PRBool doDecrypt,
+    unsigned char *out, int *outlen, int maxout,
+    const unsigned char *in, int inlen,
+    const unsigned char *additionalData, int additionalDataLen);
+static SECStatus tls13_SendServerHelloSequence(sslSocket *ss);
+static SECStatus tls13_SendEncryptedExtensions(sslSocket *ss);
+static void tls13_SetKeyExchangeType(sslSocket *ss, const sslNamedGroupDef *group);
+static SECStatus tls13_HandleClientKeyShare(sslSocket *ss,
+                                            TLS13KeyShareEntry *peerShare);
+static SECStatus tls13_SendHelloRetryRequest(sslSocket *ss,
+                                             const sslNamedGroupDef *selectedGroup);
+
+static SECStatus tls13_HandleServerKeyShare(sslSocket *ss);
+static SECStatus tls13_HandleEncryptedExtensions(sslSocket *ss, SSL3Opaque *b,
+                                                 PRUint32 length);
+static SECStatus tls13_SendCertificate(sslSocket *ss);
+static SECStatus tls13_HandleCertificate(
+    sslSocket *ss, SSL3Opaque *b, PRUint32 length);
+static SECStatus tls13_HandleCertificateRequest(sslSocket *ss, SSL3Opaque *b,
+                                                PRUint32 length);
+static SECStatus
+tls13_SendCertificateVerify(sslSocket *ss, SECKEYPrivateKey *privKey);
+static SECStatus tls13_HandleCertificateVerify(
+    sslSocket *ss, SSL3Opaque *b, PRUint32 length,
+    SSL3Hashes *hashes);
+static SECStatus tls13_RecoverWrappedSharedSecret(sslSocket *ss,
+                                                  sslSessionID *sid);
+static SECStatus
+tls13_DeriveSecret(sslSocket *ss, PK11SymKey *key,
+                   const char *prefix,
+                   const char *suffix,
+                   const SSL3Hashes *hashes,
+                   PK11SymKey **dest);
+static void tls13_SetNullCipherSpec(sslSocket *ss, ssl3CipherSpec **specp);
+static SECStatus tls13_SendEndOfEarlyData(sslSocket *ss);
+static SECStatus tls13_SendFinished(sslSocket *ss, PK11SymKey *baseKey);
+static SECStatus tls13_ComputePskBinderHash(sslSocket *ss,
+                                            unsigned long prefixLength,
+                                            SSL3Hashes *hashes);
+static SECStatus tls13_VerifyFinished(sslSocket *ss, SSL3HandshakeType message,
+                                      PK11SymKey *secret,
+                                      SSL3Opaque *b, PRUint32 length,
+                                      const SSL3Hashes *hashes);
+static SECStatus tls13_ClientHandleFinished(sslSocket *ss,
+                                            SSL3Opaque *b, PRUint32 length,
+                                            const SSL3Hashes *hashes);
+static SECStatus tls13_ServerHandleFinished(sslSocket *ss,
+                                            SSL3Opaque *b, PRUint32 length,
+                                            const SSL3Hashes *hashes);
+static SECStatus tls13_HandleNewSessionTicket(sslSocket *ss, SSL3Opaque *b,
+                                              PRUint32 length);
+static SECStatus tls13_ComputeHandshakeHashes(sslSocket *ss,
+                                              SSL3Hashes *hashes);
+static SECStatus tls13_ComputeEarlySecrets(sslSocket *ss);
+static SECStatus tls13_ComputeHandshakeSecrets(sslSocket *ss);
+static SECStatus tls13_ComputeApplicationSecrets(sslSocket *ss);
+static SECStatus tls13_ComputeFinalSecrets(sslSocket *ss);
+static SECStatus tls13_ComputeFinished(
+    sslSocket *ss, PK11SymKey *baseKey, const SSL3Hashes *hashes,
+    PRBool sending, PRUint8 *output, unsigned int *outputLen,
+    unsigned int maxOutputLen);
+static SECStatus tls13_SendClientSecondRound(sslSocket *ss);
+static SECStatus tls13_FinishHandshake(sslSocket *ss);
+
+const char kHkdfLabelClient[] = "client";
+const char kHkdfLabelServer[] = "server";
+const char kHkdfLabelPskBinderKey[] = "resumption psk binder key";
+const char kHkdfLabelEarlyTrafficSecret[] = "early traffic secret";
+const char kHkdfLabelEarlyExporterSecret[] = "early exporter master secret";
+const char kHkdfLabelHandshakeTrafficSecret[] = "handshake traffic secret";
+const char kHkdfLabelApplicationTrafficSecret[] = "application traffic secret";
+const char kHkdfLabelFinishedSecret[] = "finished";
+const char kHkdfLabelResumptionMasterSecret[] = "resumption master secret";
+const char kHkdfLabelExporterMasterSecret[] = "exporter master secret";
+const char kHkdfPurposeKey[] = "key";
+const char kHkdfPurposeIv[] = "iv";
+
+#define TRAFFIC_SECRET(ss, dir, name) ((ss->sec.isServer ^            \
+                                        (dir == CipherSpecWrite))     \
+                                           ? ss->ssl3.hs.client##name \
+                                           : ss->ssl3.hs.server##name)
+
+const SSL3ProtocolVersion kTlsRecordVersion = SSL_LIBRARY_VERSION_TLS_1_0;
+const SSL3ProtocolVersion kDtlsRecordVersion = SSL_LIBRARY_VERSION_TLS_1_1;
+
+/* Belt and suspenders in case we ever add a TLS 1.4. */
+PR_STATIC_ASSERT(SSL_LIBRARY_VERSION_MAX_SUPPORTED <=
+                 SSL_LIBRARY_VERSION_TLS_1_3);
+
+/* Use this instead of FATAL_ERROR when an alert isn't possible. */
+#define LOG_ERROR(ss, prError)                                                     \
+    do {                                                                           \
+        SSL_TRC(3, ("%d: TLS13[%d]: fatal error %d in %s (%s:%d)",                 \
+                    SSL_GETPID(), ss->fd, prError, __func__, __FILE__, __LINE__)); \
+        PORT_SetError(prError);                                                    \
+    } while (0)
+
+/* Log an error and generate an alert because something is irreparably wrong. */
+#define FATAL_ERROR(ss, prError, desc)       \
+    do {                                     \
+        LOG_ERROR(ss, prError);              \
+        tls13_FatalError(ss, prError, desc); \
+    } while (0)
+
+void
+tls13_FatalError(sslSocket *ss, PRErrorCode prError, SSL3AlertDescription desc)
+{
+    PORT_Assert(desc != internal_error); /* These should never happen */
+    (void)SSL3_SendAlert(ss, alert_fatal, desc);
+    PORT_SetError(prError);
+}
+
+#ifdef TRACE
+#define STATE_CASE(a) \
+    case a:           \
+        return #a
+static char *
+tls13_HandshakeState(SSL3WaitState st)
+{
+    switch (st) {
+        STATE_CASE(wait_client_hello);
+        STATE_CASE(wait_client_cert);
+        STATE_CASE(wait_cert_verify);
+        STATE_CASE(wait_finished);
+        STATE_CASE(wait_server_hello);
+        STATE_CASE(wait_server_cert);
+        STATE_CASE(wait_cert_request);
+        STATE_CASE(wait_encrypted_extensions);
+        STATE_CASE(idle_handshake);
+        default:
+            break;
+    }
+    PORT_Assert(0);
+    return "unknown";
+}
+#endif
+
+#define TLS13_WAIT_STATE_MASK 0x80
+
+#define TLS13_BASE_WAIT_STATE(ws) (ws & ~TLS13_WAIT_STATE_MASK)
+/* We don't mask idle_handshake because other parts of the code use it*/
+#define TLS13_WAIT_STATE(ws) (((ws == idle_handshake) || (ws == wait_server_hello)) ? ws : ws | TLS13_WAIT_STATE_MASK)
+#define TLS13_CHECK_HS_STATE(ss, err, ...)                          \
+    tls13_CheckHsState(ss, err, #err, __func__, __FILE__, __LINE__, \
+                       __VA_ARGS__,                                 \
+                       wait_invalid)
+void
+tls13_SetHsState(sslSocket *ss, SSL3WaitState ws,
+                 const char *func, const char *file, int line)
+{
+#ifdef TRACE
+    const char *new_state_name =
+        tls13_HandshakeState(ws);
+
+    SSL_TRC(3, ("%d: TLS13[%d]: %s state change from %s->%s in %s (%s:%d)",
+                SSL_GETPID(), ss->fd, SSL_ROLE(ss),
+                tls13_HandshakeState(TLS13_BASE_WAIT_STATE(ss->ssl3.hs.ws)),
+                new_state_name,
+                func, file, line));
+#endif
+
+    ss->ssl3.hs.ws = TLS13_WAIT_STATE(ws);
+}
+
+static PRBool
+tls13_InHsStateV(sslSocket *ss, va_list ap)
+{
+    SSL3WaitState ws;
+
+    while ((ws = va_arg(ap, SSL3WaitState)) != wait_invalid) {
+        if (TLS13_WAIT_STATE(ws) == ss->ssl3.hs.ws) {
+            return PR_TRUE;
+        }
+    }
+    return PR_FALSE;
+}
+
+PRBool
+tls13_InHsState(sslSocket *ss, ...)
+{
+    PRBool found;
+    va_list ap;
+
+    va_start(ap, ss);
+    found = tls13_InHsStateV(ss, ap);
+    va_end(ap);
+
+    return found;
+}
+
+static SECStatus
+tls13_CheckHsState(sslSocket *ss, int err, const char *error_name,
+                   const char *func, const char *file, int line,
+                   ...)
+{
+    va_list ap;
+    va_start(ap, line);
+    if (tls13_InHsStateV(ss, ap)) {
+        va_end(ap);
+        return SECSuccess;
+    }
+    va_end(ap);
+
+    SSL_TRC(3, ("%d: TLS13[%d]: error %s state is (%s) at %s (%s:%d)",
+                SSL_GETPID(), ss->fd,
+                error_name,
+                tls13_HandshakeState(TLS13_BASE_WAIT_STATE(ss->ssl3.hs.ws)),
+                func, file, line));
+    tls13_FatalError(ss, err, unexpected_message);
+    return SECFailure;
+}
+
+SSLHashType
+tls13_GetHashForCipherSuite(ssl3CipherSuite suite)
+{
+    const ssl3CipherSuiteDef *cipherDef =
+        ssl_LookupCipherSuiteDef(suite);
+    PORT_Assert(cipherDef);
+    if (!cipherDef) {
+        return ssl_hash_none;
+    }
+    return cipherDef->prf_hash;
+}
+
+SSLHashType
+tls13_GetHash(const sslSocket *ss)
+{
+    /* All TLS 1.3 cipher suites must have an explict PRF hash. */
+    PORT_Assert(ss->ssl3.hs.suite_def->prf_hash != ssl_hash_none);
+    return ss->ssl3.hs.suite_def->prf_hash;
+}
+
+unsigned int
+tls13_GetHashSizeForHash(SSLHashType hash)
+{
+    switch (hash) {
+        case ssl_hash_sha256:
+            return 32;
+        case ssl_hash_sha384:
+            return 48;
+        default:
+            PORT_Assert(0);
+    }
+    return 32;
+}
+
+unsigned int
+tls13_GetHashSize(const sslSocket *ss)
+{
+    return tls13_GetHashSizeForHash(tls13_GetHash(ss));
+}
+
+static CK_MECHANISM_TYPE
+tls13_GetHkdfMechanismForHash(SSLHashType hash)
+{
+    switch (hash) {
+        case ssl_hash_sha256:
+            return CKM_NSS_HKDF_SHA256;
+        case ssl_hash_sha384:
+            return CKM_NSS_HKDF_SHA384;
+        default:
+            PORT_Assert(0);
+    }
+    return CKM_NSS_HKDF_SHA256;
+}
+
+CK_MECHANISM_TYPE
+tls13_GetHkdfMechanism(sslSocket *ss)
+{
+    return tls13_GetHkdfMechanismForHash(tls13_GetHash(ss));
+}
+
+static CK_MECHANISM_TYPE
+tls13_GetHmacMechanism(sslSocket *ss)
+{
+    switch (tls13_GetHash(ss)) {
+        case ssl_hash_sha256:
+            return CKM_SHA256_HMAC;
+        case ssl_hash_sha384:
+            return CKM_SHA384_HMAC;
+        default:
+            PORT_Assert(0);
+    }
+    return CKM_SHA256_HMAC;
+}
+
+SECStatus
+tls13_CreateKeyShare(sslSocket *ss, const sslNamedGroupDef *groupDef)
+{
+    SECStatus rv;
+    sslEphemeralKeyPair *keyPair = NULL;
+    const ssl3DHParams *params;
+
+    PORT_Assert(groupDef);
+    switch (groupDef->keaType) {
+        case ssl_kea_ecdh:
+            rv = ssl_CreateECDHEphemeralKeyPair(ss, groupDef, &keyPair);
+            if (rv != SECSuccess) {
+                return SECFailure;
+            }
+            break;
+        case ssl_kea_dh:
+            params = ssl_GetDHEParams(groupDef);
+            PORT_Assert(params->name != ssl_grp_ffdhe_custom);
+            rv = ssl_CreateDHEKeyPair(groupDef, params, &keyPair);
+            if (rv != SECSuccess) {
+                return SECFailure;
+            }
+            break;
+        default:
+            PORT_Assert(0);
+            PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
+            return SECFailure;
+    }
+
+    PR_APPEND_LINK(&keyPair->link, &ss->ephemeralKeyPairs);
+    return rv;
+}
+
+SECStatus
+SSL_SendAdditionalKeyShares(PRFileDesc *fd, unsigned int count)
+{
+    sslSocket *ss = ssl_FindSocket(fd);
+    if (!ss) {
+        PORT_SetError(SEC_ERROR_INVALID_ARGS);
+        return SECFailure;
+    }
+
+    ss->additionalShares = count;
+    return SECSuccess;
+}
+
+/*
+ * Generate shares for ECDHE and FFDHE.  This picks the first enabled group of
+ * the requisite type and creates a share for that.
+ *
+ * Called from ssl3_SendClientHello.
+ */
+SECStatus
+tls13_SetupClientHello(sslSocket *ss)
+{
+    unsigned int i;
+    SSL3Statistics *ssl3stats = SSL_GetStatistics();
+    NewSessionTicket *session_ticket = NULL;
+    sslSessionID *sid = ss->sec.ci.sid;
+    unsigned int numShares = 0;
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveXmitBufLock(ss));
+    PORT_Assert(PR_CLIST_IS_EMPTY(&ss->ephemeralKeyPairs));
+
+    /* Select the first enabled group.
+     * TODO(ekr@rtfm.com): be smarter about offering the group
+     * that the other side negotiated if we are resuming. */
+    for (i = 0; i < SSL_NAMED_GROUP_COUNT; ++i) {
+        SECStatus rv;
+        if (!ss->namedGroupPreferences[i]) {
+            continue;
+        }
+        rv = tls13_CreateKeyShare(ss, ss->namedGroupPreferences[i]);
+        if (rv != SECSuccess) {
+            return SECFailure;
+        }
+        if (++numShares > ss->additionalShares) {
+            break;
+        }
+    }
+
+    if (PR_CLIST_IS_EMPTY(&ss->ephemeralKeyPairs)) {
+        PORT_SetError(SSL_ERROR_NO_CIPHERS_SUPPORTED);
+        return SECFailure;
+    }
+
+    /* Below here checks if we can do stateless resumption. */
+    if (sid->cached == never_cached ||
+        sid->version < SSL_LIBRARY_VERSION_TLS_1_3) {
+        return SECSuccess;
+    }
+
+    /* The caller must be holding sid->u.ssl3.lock for reading. */
+    session_ticket = &sid->u.ssl3.locked.sessionTicket;
+    PORT_Assert(session_ticket && session_ticket->ticket.data);
+
+    if (session_ticket->ticket_lifetime_hint == 0 ||
+        (session_ticket->ticket_lifetime_hint +
+             session_ticket->received_timestamp >
+         ssl_Time())) {
+        ss->statelessResume = PR_TRUE;
+    }
+
+    if (ss->statelessResume) {
+        SECStatus rv;
+
+        PORT_Assert(ss->sec.ci.sid);
+        rv = tls13_RecoverWrappedSharedSecret(ss, ss->sec.ci.sid);
+        if (rv != SECSuccess) {
+            FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+            SSL_AtomicIncrementLong(&ssl3stats->sch_sid_cache_not_ok);
+            ss->sec.uncache(ss->sec.ci.sid);
+            ssl_FreeSID(ss->sec.ci.sid);
+            ss->sec.ci.sid = NULL;
+            return SECFailure;
+        }
+
+        rv = ssl3_SetCipherSuite(ss, ss->sec.ci.sid->u.ssl3.cipherSuite, PR_FALSE);
+        if (rv != SECSuccess) {
+            FATAL_ERROR(ss, PORT_GetError(), internal_error);
+            return SECFailure;
+        }
+
+        rv = tls13_ComputeEarlySecrets(ss);
+        if (rv != SECSuccess) {
+            FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+            return SECFailure;
+        }
+    }
+
+    return SECSuccess;
+}
+
+static SECStatus
+tls13_ImportDHEKeyShare(sslSocket *ss, SECKEYPublicKey *peerKey,
+                        SSL3Opaque *b, PRUint32 length,
+                        SECKEYPublicKey *pubKey)
+{
+    SECStatus rv;
+    SECItem publicValue = { siBuffer, NULL, 0 };
+
+    publicValue.data = b;
+    publicValue.len = length;
+    if (!ssl_IsValidDHEShare(&pubKey->u.dh.prime, &publicValue)) {
+        PORT_SetError(SSL_ERROR_RX_MALFORMED_DHE_KEY_SHARE);
+        return SECFailure;
+    }
+
+    peerKey->keyType = dhKey;
+    rv = SECITEM_CopyItem(peerKey->arena, &peerKey->u.dh.prime,
+                          &pubKey->u.dh.prime);
+    if (rv != SECSuccess)
+        return SECFailure;
+    rv = SECITEM_CopyItem(peerKey->arena, &peerKey->u.dh.base,
+                          &pubKey->u.dh.base);
+    if (rv != SECSuccess)
+        return SECFailure;
+    rv = SECITEM_CopyItem(peerKey->arena, &peerKey->u.dh.publicValue,
+                          &publicValue);
+    if (rv != SECSuccess)
+        return SECFailure;
+
+    return SECSuccess;
+}
+
+static SECStatus
+tls13_HandleKeyShare(sslSocket *ss,
+                     TLS13KeyShareEntry *entry,
+                     sslKeyPair *keyPair)
+{
+    PORTCheapArenaPool arena;
+    SECKEYPublicKey *peerKey;
+    CK_MECHANISM_TYPE mechanism;
+    PRErrorCode errorCode;
+    SECStatus rv;
+
+    PORT_InitCheapArena(&arena, DER_DEFAULT_CHUNKSIZE);
+    peerKey = PORT_ArenaZNew(&arena.arena, SECKEYPublicKey);
+    if (peerKey == NULL) {
+        goto loser;
+    }
+    peerKey->arena = &arena.arena;
+    peerKey->pkcs11Slot = NULL;
+    peerKey->pkcs11ID = CK_INVALID_HANDLE;
+
+    switch (entry->group->keaType) {
+        case ssl_kea_ecdh:
+            rv = ssl_ImportECDHKeyShare(ss, peerKey,
+                                        entry->key_exchange.data,
+                                        entry->key_exchange.len,
+                                        entry->group);
+            mechanism = CKM_ECDH1_DERIVE;
+            break;
+        case ssl_kea_dh:
+            rv = tls13_ImportDHEKeyShare(ss, peerKey,
+                                         entry->key_exchange.data,
+                                         entry->key_exchange.len,
+                                         keyPair->pubKey);
+            mechanism = CKM_DH_PKCS_DERIVE;
+            break;
+        default:
+            PORT_Assert(0);
+            goto loser;
+    }
+    if (rv != SECSuccess) {
+        goto loser;
+    }
+
+    ss->ssl3.hs.dheSecret = PK11_PubDeriveWithKDF(
+        keyPair->privKey, peerKey, PR_FALSE, NULL, NULL, mechanism,
+        tls13_GetHkdfMechanism(ss), CKA_DERIVE, 0, CKD_NULL, NULL, NULL);
+    if (!ss->ssl3.hs.dheSecret) {
+        ssl_MapLowLevelError(SSL_ERROR_KEY_EXCHANGE_FAILURE);
+        goto loser;
+    }
+    PORT_DestroyCheapArena(&arena);
+    return SECSuccess;
+
+loser:
+    PORT_DestroyCheapArena(&arena);
+    errorCode = PORT_GetError(); /* don't overwrite the error code */
+    tls13_FatalError(ss, errorCode, illegal_parameter);
+    return SECFailure;
+}
+
+SECStatus
+tls13_HandlePostHelloHandshakeMessage(sslSocket *ss, SSL3Opaque *b,
+                                      PRUint32 length, SSL3Hashes *hashesPtr)
+{
+    if (ss->sec.isServer && ss->ssl3.hs.zeroRttIgnore != ssl_0rtt_ignore_none) {
+        SSL_TRC(3, ("%d: TLS13[%d]: %s successfully decrypted handshake after"
+                    "failed 0-RTT",
+                    SSL_GETPID(), ss->fd));
+        ss->ssl3.hs.zeroRttIgnore = ssl_0rtt_ignore_none;
+    }
+
+    /* TODO(ekr@rtfm.com): Would it be better to check all the states here? */
+    switch (ss->ssl3.hs.msg_type) {
+        case certificate:
+            return tls13_HandleCertificate(ss, b, length);
+
+        case certificate_request:
+            return tls13_HandleCertificateRequest(ss, b, length);
+
+        case certificate_verify:
+            if (!hashesPtr) {
+                FATAL_ERROR(ss, SSL_ERROR_RX_UNEXPECTED_CERT_VERIFY, unexpected_message);
+                return SECFailure;
+            }
+            return tls13_HandleCertificateVerify(ss, b, length, hashesPtr);
+
+        case encrypted_extensions:
+            return tls13_HandleEncryptedExtensions(ss, b, length);
+
+        case new_session_ticket:
+            return tls13_HandleNewSessionTicket(ss, b, length);
+
+        case finished:
+            if (!hashesPtr) {
+                FATAL_ERROR(ss, SSL_ERROR_RX_UNEXPECTED_FINISHED, unexpected_message);
+                return SECFailure;
+            }
+            if (ss->sec.isServer) {
+                return tls13_ServerHandleFinished(ss, b, length, hashesPtr);
+            } else {
+                return tls13_ClientHandleFinished(ss, b, length, hashesPtr);
+            }
+
+        default:
+            FATAL_ERROR(ss, SSL_ERROR_RX_UNKNOWN_HANDSHAKE, unexpected_message);
+            return SECFailure;
+    }
+
+    PORT_Assert(0); /* Unreached */
+    return SECFailure;
+}
+
+static SECStatus
+tls13_RecoverWrappedSharedSecret(sslSocket *ss, sslSessionID *sid)
+{
+    PK11SymKey *wrapKey; /* wrapping key */
+    SECItem wrappedMS = { siBuffer, NULL, 0 };
+    SSLHashType hashType;
+
+    SSL_TRC(3, ("%d: TLS13[%d]: recovering static secret (%s)",
+                SSL_GETPID(), ss->fd, SSL_ROLE(ss)));
+    if (!sid->u.ssl3.keys.msIsWrapped) {
+        PORT_Assert(0); /* I think this can't happen. */
+        return SECFailure;
+    }
+
+    /* Now find the hash used as the PRF for the previous handshake. */
+    hashType = tls13_GetHashForCipherSuite(sid->u.ssl3.cipherSuite);
+
+    /* If we are the server, we compute the wrapping key, but if we
+     * are the client, it's coordinates are stored with the ticket. */
+    if (ss->sec.isServer) {
+        const sslServerCert *serverCert;
+
+        serverCert = ssl_FindServerCert(ss, &sid->certType);
+        PORT_Assert(serverCert);
+        wrapKey = ssl3_GetWrappingKey(ss, NULL, serverCert,
+                                      sid->u.ssl3.masterWrapMech,
+                                      ss->pkcs11PinArg);
+    } else {
+        PK11SlotInfo *slot = SECMOD_LookupSlot(sid->u.ssl3.masterModuleID,
+                                               sid->u.ssl3.masterSlotID);
+        if (!slot)
+            return SECFailure;
+
+        wrapKey = PK11_GetWrapKey(slot,
+                                  sid->u.ssl3.masterWrapIndex,
+                                  sid->u.ssl3.masterWrapMech,
+                                  sid->u.ssl3.masterWrapSeries,
+                                  ss->pkcs11PinArg);
+        PK11_FreeSlot(slot);
+    }
+    if (!wrapKey) {
+        return SECFailure;
+    }
+
+    wrappedMS.data = sid->u.ssl3.keys.wrapped_master_secret;
+    wrappedMS.len = sid->u.ssl3.keys.wrapped_master_secret_len;
+
+    /* unwrap the "master secret" which is actually RMS. */
+    ss->ssl3.hs.resumptionMasterSecret = PK11_UnwrapSymKeyWithFlags(
+        wrapKey, sid->u.ssl3.masterWrapMech,
+        NULL, &wrappedMS,
+        CKM_SSL3_MASTER_KEY_DERIVE,
+        CKA_DERIVE,
+        tls13_GetHashSizeForHash(hashType),
+        CKF_SIGN | CKF_VERIFY);
+    PK11_FreeSymKey(wrapKey);
+    if (!ss->ssl3.hs.resumptionMasterSecret) {
+        return SECFailure;
+    }
+
+    PRINT_KEY(50, (ss, "Recovered RMS", ss->ssl3.hs.resumptionMasterSecret));
+
+    return SECSuccess;
+}
+
+/* Key Derivation Functions.
+ *
+ * Below is the key schedule from [draft-ietf-tls-tls13].
+ *
+ * * The relevant functions from this file are indicated by tls13_Foo().
+ *                 0
+ *                 |
+ *                 v
+ *   PSK ->  HKDF-Extract
+ *                 |
+ *                 v
+ *           Early Secret ---> Derive-Secret(., "client early traffic secret",
+ *                 |                         ClientHello)
+ *                 |                         = client_early_traffic_secret
+ *                 v
+ * (EC)DHE -> HKDF-Extract
+ *                 |
+ *                 v
+ *         Handshake Secret
+ *                 |
+ *                 +---------> Derive-Secret(., "client handshake traffic secret",
+ *                 |                         ClientHello...ServerHello)
+ *                 |                         = client_handshake_traffic_secret
+ *                 |
+ *                 +---------> Derive-Secret(., "server handshake traffic secret",
+ *                 |                         ClientHello...ServerHello)
+ *                 |                         = server_handshake_traffic_secret
+ *                 |
+ *                 v
+ *      0 -> HKDF-Extract
+ *                 |
+ *                 v
+ *            Master Secret
+ *                 |
+ *                 +---------> Derive-Secret(., "client application traffic secret",
+ *                 |                         ClientHello...Server Finished)
+ *                 |                         = client_traffic_secret_0
+ *                 |
+ *                 +---------> Derive-Secret(., "server application traffic secret",
+ *                 |                         ClientHello...Server Finished)
+ *                 |                         = server_traffic_secret_0
+ *                 |
+ *                 +---------> Derive-Secret(., "exporter master secret",
+ *                 |                         ClientHello...Client Finished)
+ *                 |                         = exporter_secret
+ *                 |
+ *                 +---------> Derive-Secret(., "resumption master secret",
+ *                                           ClientHello...Client Finished)
+ *                                           = resumption_secret
+ *
+ */
+
+static SECStatus
+tls13_ComputeEarlySecrets(sslSocket *ss)
+{
+    SECStatus rv = SECSuccess;
+
+    SSL_TRC(5, ("%d: TLS13[%d]: compute early secrets (%s)",
+                SSL_GETPID(), ss->fd, SSL_ROLE(ss)));
+
+    /* Extract off the resumptionMasterSecret (if present), else pass the NULL
+     * resumptionMasterSecret which will be internally translated to zeroes. */
+    PORT_Assert(!ss->ssl3.hs.currentSecret);
+    rv = tls13_HkdfExtract(NULL, ss->ssl3.hs.resumptionMasterSecret,
+                           tls13_GetHash(ss), &ss->ssl3.hs.currentSecret);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+
+    PORT_Assert(ss->statelessResume == (ss->ssl3.hs.resumptionMasterSecret != NULL));
+    if (ss->statelessResume) {
+        PRUint8 buf[1] = { 0 };
+        SSL3Hashes hashes;
+
+        PK11_FreeSymKey(ss->ssl3.hs.resumptionMasterSecret);
+        ss->ssl3.hs.resumptionMasterSecret = NULL;
+
+        rv = PK11_HashBuf(ssl3_HashTypeToOID(tls13_GetHash(ss)),
+                          hashes.u.raw, buf, 0);
+        if (rv != SECSuccess) {
+            FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+            return SECFailure;
+        }
+        hashes.len = tls13_GetHashSize(ss);
+
+        rv = tls13_DeriveSecret(ss, ss->ssl3.hs.currentSecret,
+                                NULL, kHkdfLabelPskBinderKey, &hashes,
+                                &ss->ssl3.hs.pskBinderKey);
+        if (rv != SECSuccess) {
+            return SECFailure;
+        }
+
+        rv = tls13_DeriveSecret(ss, ss->ssl3.hs.currentSecret,
+                                NULL, kHkdfLabelEarlyExporterSecret,
+                                &hashes, &ss->ssl3.hs.earlyExporterSecret);
+        if (rv != SECSuccess) {
+            return SECFailure;
+        }
+    } else {
+        PORT_Assert(!ss->ssl3.hs.resumptionMasterSecret);
+    }
+
+    return SECSuccess;
+}
+
+static SECStatus
+tls13_ComputeHandshakeSecrets(sslSocket *ss)
+{
+    SECStatus rv;
+    PK11SymKey *newSecret = NULL;
+
+    SSL_TRC(5, ("%d: TLS13[%d]: compute handshake secrets (%s)",
+                SSL_GETPID(), ss->fd, SSL_ROLE(ss)));
+
+    /* First update |currentSecret| to add |dheSecret|, if any. */
+    PORT_Assert(ss->ssl3.hs.currentSecret);
+    PORT_Assert(ss->ssl3.hs.dheSecret);
+    rv = tls13_HkdfExtract(ss->ssl3.hs.currentSecret, ss->ssl3.hs.dheSecret,
+                           tls13_GetHash(ss), &newSecret);
+    if (rv != SECSuccess) {
+        LOG_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE);
+        return rv;
+    }
+    PK11_FreeSymKey(ss->ssl3.hs.dheSecret);
+    ss->ssl3.hs.dheSecret = NULL;
+    PK11_FreeSymKey(ss->ssl3.hs.currentSecret);
+    ss->ssl3.hs.currentSecret = newSecret;
+
+    /* Now compute |*HsTrafficSecret| */
+    rv = tls13_DeriveSecret(ss, ss->ssl3.hs.currentSecret,
+                            kHkdfLabelClient,
+                            kHkdfLabelHandshakeTrafficSecret, NULL,
+                            &ss->ssl3.hs.clientHsTrafficSecret);
+    if (rv != SECSuccess) {
+        LOG_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE);
+        return rv;
+    }
+    rv = tls13_DeriveSecret(ss, ss->ssl3.hs.currentSecret,
+                            kHkdfLabelServer,
+                            kHkdfLabelHandshakeTrafficSecret, NULL,
+                            &ss->ssl3.hs.serverHsTrafficSecret);
+    if (rv != SECSuccess) {
+        LOG_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE);
+        return rv;
+    }
+
+    SSL_TRC(5, ("%d: TLS13[%d]: compute master secret (%s)",
+                SSL_GETPID(), ss->fd, SSL_ROLE(ss)));
+
+    /* Crank HKDF forward to make master secret, which we
+     * stuff in current secret. */
+    rv = tls13_HkdfExtract(ss->ssl3.hs.currentSecret,
+                           NULL,
+                           tls13_GetHash(ss),
+                           &newSecret);
+
+    if (rv != SECSuccess) {
+        LOG_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE);
+        return SECFailure;
+    }
+    PK11_FreeSymKey(ss->ssl3.hs.currentSecret);
+    ss->ssl3.hs.currentSecret = newSecret;
+
+    return SECSuccess;
+}
+
+static SECStatus
+tls13_ComputeApplicationSecrets(sslSocket *ss)
+{
+    SECStatus rv;
+
+    rv = tls13_DeriveSecret(ss, ss->ssl3.hs.currentSecret,
+                            kHkdfLabelClient,
+                            kHkdfLabelApplicationTrafficSecret,
+                            NULL,
+                            &ss->ssl3.hs.clientTrafficSecret);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+    rv = tls13_DeriveSecret(ss, ss->ssl3.hs.currentSecret,
+                            kHkdfLabelServer,
+                            kHkdfLabelApplicationTrafficSecret,
+                            NULL,
+                            &ss->ssl3.hs.serverTrafficSecret);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+
+    rv = tls13_DeriveSecret(ss, ss->ssl3.hs.currentSecret,
+                            NULL, kHkdfLabelExporterMasterSecret,
+                            NULL, &ss->ssl3.hs.exporterSecret);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+
+    return SECSuccess;
+}
+
+static SECStatus
+tls13_ComputeFinalSecrets(sslSocket *ss)
+{
+    SECStatus rv;
+    PK11SymKey *resumptionMasterSecret = NULL;
+
+    PORT_Assert(!ss->ssl3.crSpec->master_secret);
+    PORT_Assert(!ss->ssl3.cwSpec->master_secret);
+
+    rv = tls13_DeriveSecret(ss, ss->ssl3.hs.currentSecret,
+                            NULL, kHkdfLabelResumptionMasterSecret,
+                            NULL, &resumptionMasterSecret);
+    PK11_FreeSymKey(ss->ssl3.hs.currentSecret);
+    ss->ssl3.hs.currentSecret = NULL;
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+
+    /* This is pretty gross. TLS 1.3 uses a number of master secrets:
+     * The master secret to generate the keys and then the resumption
+     * master secret for future connections. To make this work without
+     * refactoring too much of the SSLv3 code, we store the RMS in
+     * |crSpec->master_secret| and |cwSpec->master_secret|.
+     */
+    ss->ssl3.crSpec->master_secret = resumptionMasterSecret;
+    ss->ssl3.cwSpec->master_secret =
+        PK11_ReferenceSymKey(ss->ssl3.crSpec->master_secret);
+
+    return SECSuccess;
+}
+
+static void
+tls13_RestoreCipherInfo(sslSocket *ss, sslSessionID *sid)
+{
+    /* Set these to match the cached value.
+     * TODO(ekr@rtfm.com): Make a version with the "true" values.
+     * Bug 1256137.
+     */
+    ss->sec.authType = sid->authType;
+    ss->sec.authKeyBits = sid->authKeyBits;
+}
+
+/* Check whether resumption-PSK is allowed. */
+static PRBool
+tls13_CanResume(sslSocket *ss, const sslSessionID *sid)
+{
+    const sslServerCert *sc;
+
+    if (!sid) {
+        return PR_FALSE;
+    }
+
+    if (sid->version != ss->version) {
+        return PR_FALSE;
+    }
+
+    if (tls13_GetHashForCipherSuite(sid->u.ssl3.cipherSuite) != tls13_GetHashForCipherSuite(ss->ssl3.hs.cipher_suite)) {
+        return PR_FALSE;
+    }
+
+    /* Server sids don't remember the server cert we previously sent, but they
+     * do remember the type of certificate we originally used, so we can locate
+     * it again, provided that the current ssl socket has had its server certs
+     * configured the same as the previous one. */
+    sc = ssl_FindServerCert(ss, &sid->certType);
+    if (!sc || !sc->serverCert) {
+        return PR_FALSE;
+    }
+
+    return PR_TRUE;
+}
+
+static PRBool
+tls13_AlpnTagAllowed(const sslSocket *ss, const SECItem *tag)
+{
+    const unsigned char *data = ss->opt.nextProtoNego.data;
+    unsigned int length = ss->opt.nextProtoNego.len;
+    unsigned int offset = 0;
+
+    if (!tag->len)
+        return PR_TRUE;
+
+    while (offset < length) {
+        unsigned int taglen = (unsigned int)data[offset];
+        if ((taglen == tag->len) &&
+            !PORT_Memcmp(data + offset + 1, tag->data, tag->len))
+            return PR_TRUE;
+        offset += 1 + taglen;
+    }
+
+    return PR_FALSE;
+}
+
+static PRBool
+tls13_CanNegotiateZeroRtt(sslSocket *ss, const sslSessionID *sid)
+{
+    PORT_Assert(ss->ssl3.hs.zeroRttState == ssl_0rtt_sent);
+
+    if (!sid)
+        return PR_FALSE;
+    PORT_Assert(ss->statelessResume);
+    if (!ss->statelessResume)
+        return PR_FALSE;
+    if (ss->ssl3.hs.cipher_suite != sid->u.ssl3.cipherSuite)
+        return PR_FALSE;
+    if (!ss->opt.enable0RttData)
+        return PR_FALSE;
+    if (!(sid->u.ssl3.locked.sessionTicket.flags & ticket_allow_early_data))
+        return PR_FALSE;
+    if (SECITEM_CompareItem(&ss->xtnData.nextProto,
+                            &sid->u.ssl3.alpnSelection) != 0)
+        return PR_FALSE;
+
+    return PR_TRUE;
+}
+
+/* Called from tls13_HandleClientHelloPart2 to update the state of 0-RTT handling.
+ *
+ * 0-RTT is only permitted if:
+ * 1. The early data extension was present.
+ * 2. We are resuming a session.
+ * 3. The 0-RTT option is set.
+ * 4. The ticket allowed 0-RTT.
+ * 5. We negotiated the same ALPN value as in the ticket.
+ */
+static void
+tls13_NegotiateZeroRtt(sslSocket *ss, const sslSessionID *sid)
+{
+    SSL_TRC(3, ("%d: TLS13[%d]: negotiate 0-RTT %p",
+                SSL_GETPID(), ss->fd, sid));
+
+    /* tls13_ServerHandleEarlyDataXtn sets this to ssl_0rtt_sent, so this will
+     * be ssl_0rtt_none unless early_data is present. */
+    if (ss->ssl3.hs.zeroRttState == ssl_0rtt_none) {
+        return;
+    }
+
+    /* If we rejected 0-RTT on the first ClientHello, then we can just say that
+     * there is no 0-RTT for the second.  We shouldn't get any more.  Reset the
+     * ignore state so that we treat decryption failure normally. */
+    if (ss->ssl3.hs.zeroRttIgnore == ssl_0rtt_ignore_hrr) {
+        PORT_Assert(ss->ssl3.hs.helloRetry);
+        ss->ssl3.hs.zeroRttState = ssl_0rtt_none;
+        ss->ssl3.hs.zeroRttIgnore = ssl_0rtt_ignore_none;
+        return;
+    }
+
+    if (!tls13_CanNegotiateZeroRtt(ss, sid)) {
+        SSL_TRC(3, ("%d: TLS13[%d]: ignore 0-RTT",
+                    SSL_GETPID(), ss->fd));
+        ss->ssl3.hs.zeroRttState = ssl_0rtt_ignored;
+        ss->ssl3.hs.zeroRttIgnore = ssl_0rtt_ignore_trial;
+        return;
+    }
+
+    SSL_TRC(3, ("%d: TLS13[%d]: enable 0-RTT",
+                SSL_GETPID(), ss->fd));
+    PORT_Assert(ss->statelessResume);
+    ss->ssl3.hs.zeroRttState = ssl_0rtt_accepted;
+    ss->ssl3.hs.zeroRttIgnore = ssl_0rtt_ignore_none;
+}
+
+/* Check if the offered group is acceptable. */
+static PRBool
+tls13_isGroupAcceptable(const sslNamedGroupDef *offered,
+                        const sslNamedGroupDef *preferredGroup)
+{
+    /* We accept epsilon (e) bits around the offered group size. */
+    const unsigned int e = 2;
+
+    PORT_Assert(offered);
+    PORT_Assert(preferredGroup);
+
+    if (offered->bits >= preferredGroup->bits - e &&
+        offered->bits <= preferredGroup->bits + e) {
+        return PR_TRUE;
+    }
+
+    return PR_FALSE;
+}
+
+/* Find remote key share for given group and return it.
+ * Returns NULL if no key share is found. */
+static TLS13KeyShareEntry *
+tls13_FindKeyShareEntry(sslSocket *ss, const sslNamedGroupDef *group)
+{
+    PRCList *cur_p = PR_NEXT_LINK(&ss->xtnData.remoteKeyShares);
+    while (cur_p != &ss->xtnData.remoteKeyShares) {
+        TLS13KeyShareEntry *offer = (TLS13KeyShareEntry *)cur_p;
+        if (offer->group == group) {
+            return offer;
+        }
+        cur_p = PR_NEXT_LINK(cur_p);
+    }
+    return NULL;
+}
+
+static SECStatus
+tls13_NegotiateKeyExchange(sslSocket *ss, TLS13KeyShareEntry **clientShare)
+{
+    unsigned int index;
+    TLS13KeyShareEntry *entry = NULL;
+    const sslNamedGroupDef *preferredGroup = NULL;
+
+    /* We insist on DHE. */
+    if (ss->statelessResume) {
+        if (!ssl3_ExtensionNegotiated(ss, ssl_tls13_psk_key_exchange_modes_xtn)) {
+            FATAL_ERROR(ss, SSL_ERROR_MISSING_PSK_KEY_EXCHANGE_MODES,
+                        missing_extension);
+            return SECFailure;
+        }
+        if (!memchr(ss->xtnData.psk_ke_modes.data, tls13_psk_dh_ke,
+                    ss->xtnData.psk_ke_modes.len)) {
+            SSL_TRC(3, ("%d: TLS13[%d]: client offered PSK without DH",
+                        SSL_GETPID(), ss->fd));
+            ss->statelessResume = PR_FALSE;
+        }
+    }
+
+    /* Now figure out which key share we like the best out of the
+     * mutually supported groups, regardless of what the client offered
+     * for key shares.
+     */
+    if (!ssl3_ExtensionNegotiated(ss, ssl_supported_groups_xtn)) {
+        FATAL_ERROR(ss, SSL_ERROR_MISSING_SUPPORTED_GROUPS_EXTENSION,
+                    missing_extension);
+        return SECFailure;
+    }
+
+    SSL_TRC(3, ("%d: TLS13[%d]: selected KE = %s",
+                SSL_GETPID(), ss->fd, ss->statelessResume ? "PSK + (EC)DHE" : "(EC)DHE"));
+
+    /* Find the preferred group and an according client key share available. */
+    for (index = 0; index < SSL_NAMED_GROUP_COUNT; ++index) {
+        /* Continue to the next group if this one is not enabled. */
+        if (!ss->namedGroupPreferences[index]) {
+            /* There's a gap in the preferred groups list. Assume this is a group
+             * that's not supported by the client but preferred by the server. */
+            if (preferredGroup) {
+                entry = NULL;
+                break;
+            }
+            continue;
+        }
+
+        /* Check if the client sent a key share for this group. */
+        entry = tls13_FindKeyShareEntry(ss, ss->namedGroupPreferences[index]);
+
+        if (preferredGroup) {
+            /* We already found our preferred group but the group didn't have a share. */
+            if (entry) {
+                /* The client sent a key share with group ss->namedGroupPreferences[index] */
+                if (tls13_isGroupAcceptable(ss->namedGroupPreferences[index],
+                                            preferredGroup)) {
+                    /* This is not the preferred group, but it's acceptable */
+                    preferredGroup = ss->namedGroupPreferences[index];
+                } else {
+                    /* The proposed group is not acceptable. */
+                    entry = NULL;
+                }
+            }
+            break;
+        } else {
+            /* The first enabled group is the preferred group. */
+            preferredGroup = ss->namedGroupPreferences[index];
+            if (entry) {
+                break;
+            }
+        }
+    }
+
+    if (!preferredGroup) {
+        FATAL_ERROR(ss, SSL_ERROR_NO_CYPHER_OVERLAP, handshake_failure);
+        return SECFailure;
+    }
+    SSL_TRC(3, ("%d: TLS13[%d]: group = %d", SSL_GETPID(), ss->fd,
+                preferredGroup->name));
+
+    if (!entry) {
+        return tls13_SendHelloRetryRequest(ss, preferredGroup);
+    }
+
+    PORT_Assert(preferredGroup == entry->group);
+    *clientShare = entry;
+
+    return SECSuccess;
+}
+
+SECStatus
+tls13_SelectServerCert(sslSocket *ss)
+{
+    PRCList *cursor;
+    SECStatus rv;
+
+    if (!ssl3_ExtensionNegotiated(ss, ssl_signature_algorithms_xtn)) {
+        FATAL_ERROR(ss, SSL_ERROR_MISSING_SIGNATURE_ALGORITHMS_EXTENSION,
+                    missing_extension);
+        return SECFailure;
+    }
+
+    /* This picks the first certificate that has:
+     * a) the right authentication method, and
+     * b) the right named curve (EC only)
+     *
+     * We might want to do some sort of ranking here later.  For now, it's all
+     * based on what order they are configured in. */
+    for (cursor = PR_NEXT_LINK(&ss->serverCerts);
+         cursor != &ss->serverCerts;
+         cursor = PR_NEXT_LINK(cursor)) {
+        sslServerCert *cert = (sslServerCert *)cursor;
+
+        if (cert->certType.authType == ssl_auth_rsa_pss ||
+            cert->certType.authType == ssl_auth_rsa_decrypt) {
+            continue;
+        }
+
+        rv = ssl_PickSignatureScheme(ss,
+                                     cert->serverKeyPair->pubKey,
+                                     cert->serverKeyPair->privKey,
+                                     ss->xtnData.clientSigSchemes,
+                                     ss->xtnData.numClientSigScheme,
+                                     PR_FALSE);
+        if (rv == SECSuccess) {
+            /* Found one. */
+            ss->sec.serverCert = cert;
+            ss->sec.authType = cert->certType.authType;
+            ss->ssl3.hs.kea_def_mutable.authKeyType = cert->certType.authType;
+            ss->sec.authKeyBits = cert->serverKeyBits;
+            return SECSuccess;
+        }
+    }
+
+    FATAL_ERROR(ss, SSL_ERROR_UNSUPPORTED_SIGNATURE_ALGORITHM,
+                handshake_failure);
+    return SECFailure;
+}
+
+static SECStatus
+tls13_NegotiateAuthentication(sslSocket *ss)
+{
+    SECStatus rv;
+
+    if (ss->statelessResume) {
+        SSL_TRC(3, ("%d: TLS13[%d]: selected PSK authentication",
+                    SSL_GETPID(), ss->fd));
+        ss->ssl3.hs.signatureScheme = ssl_sig_none;
+        ss->ssl3.hs.kea_def_mutable.authKeyType = ssl_auth_psk;
+        return SECSuccess;
+    }
+
+    SSL_TRC(3, ("%d: TLS13[%d]: selected certificate authentication",
+                SSL_GETPID(), ss->fd));
+    /* We've now established that we need to sign.... */
+    rv = tls13_SelectServerCert(ss);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+    ss->ssl3.hs.kea_def_mutable.authKeyType =
+        ss->sec.serverCert->certType.authType;
+    return SECSuccess;
+}
+
+/* Called from ssl3_HandleClientHello after we have parsed the
+ * ClientHello and are sure that we are going to do TLS 1.3
+ * or fail. */
+SECStatus
+tls13_HandleClientHelloPart2(sslSocket *ss,
+                             const SECItem *suites,
+                             sslSessionID *sid)
+{
+    SECStatus rv;
+    SSL3Statistics *ssl3stats = SSL_GetStatistics();
+    TLS13KeyShareEntry *clientShare = NULL;
+    int j;
+    ssl3CipherSuite previousCipherSuite;
+
+    if (ssl3_ExtensionNegotiated(ss, ssl_tls13_early_data_xtn)) {
+        ss->ssl3.hs.zeroRttState = ssl_0rtt_sent;
+
+        if (IS_DTLS(ss)) {
+            /* Save the null spec, which we should be currently reading.  We will
+             * use this when 0-RTT sending is over. */
+            ssl_GetSpecReadLock(ss);
+            ss->ssl3.hs.nullSpec = ss->ssl3.crSpec;
+            tls13_CipherSpecAddRef(ss->ssl3.hs.nullSpec);
+            PORT_Assert(ss->ssl3.hs.nullSpec->cipher_def->cipher == cipher_null);
+            ssl_ReleaseSpecReadLock(ss);
+        }
+    }
+
+#ifndef PARANOID
+    /* Look for a matching cipher suite. */
+    j = ssl3_config_match_init(ss);
+    if (j <= 0) { /* no ciphers are working/supported by PK11 */
+        FATAL_ERROR(ss, PORT_GetError(), internal_error);
+        goto loser;
+    }
+#endif
+
+    previousCipherSuite = ss->ssl3.hs.cipher_suite;
+    rv = ssl3_NegotiateCipherSuite(ss, suites, PR_FALSE);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SSL_ERROR_NO_CYPHER_OVERLAP, handshake_failure);
+        goto loser;
+    }
+    /* If we are going around again, then we should make sure that the cipher
+     * suite selection doesn't change. That's a sign of client shennanigans. */
+    if (ss->ssl3.hs.helloRetry &&
+        ss->ssl3.hs.cipher_suite != previousCipherSuite) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_CLIENT_HELLO, handshake_failure);
+        goto loser;
+    }
+
+    /* Now create a synthetic kea_def that we can tweak. */
+    ss->ssl3.hs.kea_def_mutable = *ss->ssl3.hs.kea_def;
+    ss->ssl3.hs.kea_def = &ss->ssl3.hs.kea_def_mutable;
+
+    /* Note: We call this quite a bit earlier than with TLS 1.2 and
+     * before. */
+    rv = ssl3_ServerCallSNICallback(ss);
+    if (rv != SECSuccess) {
+        goto loser; /* An alert has already been sent. */
+    }
+
+    /* Check if we could in principle resume. */
+    if (ss->statelessResume) {
+        PORT_Assert(sid);
+        if (!sid) {
+            FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+            return SECFailure;
+        }
+        if (!tls13_CanResume(ss, sid)) {
+            ss->statelessResume = PR_FALSE;
+        }
+    }
+
+    /* Select key exchange. */
+    rv = tls13_NegotiateKeyExchange(ss, &clientShare);
+    if (rv != SECSuccess) {
+        goto loser;
+    }
+
+    /* If we didn't find a client key share, we have to retry. */
+    if (!clientShare) {
+        if (sid) { /* Free the sid. */
+            ss->sec.uncache(sid);
+            ssl_FreeSID(sid);
+        }
+        PORT_Assert(ss->ssl3.hs.helloRetry);
+        return SECSuccess;
+    }
+
+    /* Select the authentication (this is also handshake shape). */
+    rv = tls13_NegotiateAuthentication(ss);
+    if (rv != SECSuccess) {
+        goto loser;
+    }
+
+    if (ss->statelessResume) {
+        /* We are now committed to trying to resume. */
+        PORT_Assert(sid);
+
+        /* Check that the negotiated SNI and the cached SNI match. */
+        if (SECITEM_CompareItem(&sid->u.ssl3.srvName,
+                                &ss->ssl3.hs.srvVirtName) != SECEqual) {
+            FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_CLIENT_HELLO,
+                        handshake_failure);
+            goto loser;
+        }
+
+        rv = tls13_RecoverWrappedSharedSecret(ss, sid);
+        if (rv != SECSuccess) {
+            SSL_AtomicIncrementLong(&ssl3stats->hch_sid_cache_not_ok);
+            FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+            goto loser;
+        }
+        tls13_RestoreCipherInfo(ss, sid);
+
+        ss->sec.serverCert = ssl_FindServerCert(ss, &sid->certType);
+        PORT_Assert(ss->sec.serverCert);
+        ss->sec.localCert = CERT_DupCertificate(ss->sec.serverCert->serverCert);
+        if (sid->peerCert != NULL) {
+            ss->sec.peerCert = CERT_DupCertificate(sid->peerCert);
+        }
+        ssl3_RegisterExtensionSender(
+            ss, &ss->xtnData,
+            ssl_tls13_pre_shared_key_xtn, tls13_ServerSendPreSharedKeyXtn);
+
+        tls13_NegotiateZeroRtt(ss, sid);
+    } else {
+        if (sid) { /* we had a sid, but it's no longer valid, free it */
+            SSL_AtomicIncrementLong(&ssl3stats->hch_sid_cache_not_ok);
+            if (ss->sec.uncache)
+                ss->sec.uncache(sid);
+            ssl_FreeSID(sid);
+            sid = NULL;
+        }
+        tls13_NegotiateZeroRtt(ss, NULL);
+    }
+
+    /* Need to compute early secrets. */
+    rv = tls13_ComputeEarlySecrets(ss);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+        return SECFailure;
+    }
+
+    /* Now that we have the binder key check the binder. */
+    if (ss->statelessResume) {
+        SSL3Hashes hashes;
+
+        rv = tls13_ComputePskBinderHash(ss, ss->xtnData.pskBinderPrefixLen,
+                                        &hashes);
+        if (rv != SECSuccess) {
+            FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+            goto loser;
+        }
+
+        rv = tls13_VerifyFinished(ss, client_hello,
+                                  ss->ssl3.hs.pskBinderKey,
+                                  ss->xtnData.pskBinder.data,
+                                  ss->xtnData.pskBinder.len,
+                                  &hashes);
+        if (rv != SECSuccess) {
+            goto loser;
+        }
+    }
+
+    /* This needs to go after we verify the psk binder. */
+    rv = ssl3_InitHandshakeHashes(ss);
+    if (rv != SECSuccess) {
+        goto loser;
+    }
+
+    /* If this is TLS 1.3 we are expecting a ClientKeyShare
+     * extension. Missing/absent extension cause failure
+     * below. */
+    rv = tls13_HandleClientKeyShare(ss, clientShare);
+    if (rv != SECSuccess) {
+        goto loser; /* An alert was sent already. */
+    }
+
+    /* From this point we are either committed to resumption, or not. */
+    if (ss->statelessResume) {
+        SSL_AtomicIncrementLong(&ssl3stats->hch_sid_cache_hits);
+        SSL_AtomicIncrementLong(&ssl3stats->hch_sid_stateless_resumes);
+    } else {
+        if (sid) {
+            /* We had a sid, but it's no longer valid, free it. */
+            SSL_AtomicIncrementLong(&ssl3stats->hch_sid_cache_not_ok);
+            ss->sec.uncache(sid);
+            ssl_FreeSID(sid);
+        } else {
+            SSL_AtomicIncrementLong(&ssl3stats->hch_sid_cache_misses);
+        }
+
+        sid = ssl3_NewSessionID(ss, PR_TRUE);
+        if (!sid) {
+            FATAL_ERROR(ss, PORT_GetError(), internal_error);
+            return SECFailure;
+        }
+    }
+    /* Take ownership of the session. */
+    ss->sec.ci.sid = sid;
+    sid = NULL;
+
+    if (ss->ssl3.hs.zeroRttState == ssl_0rtt_accepted) {
+        rv = tls13_DeriveSecret(ss, ss->ssl3.hs.currentSecret,
+                                kHkdfLabelClient,
+                                kHkdfLabelEarlyTrafficSecret,
+                                NULL, /* Current running hash. */
+                                &ss->ssl3.hs.clientEarlyTrafficSecret);
+        if (rv != SECSuccess) {
+            FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+            return SECFailure;
+        }
+    }
+
+    ssl_GetXmitBufLock(ss);
+    rv = tls13_SendServerHelloSequence(ss);
+    ssl_ReleaseXmitBufLock(ss);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, PORT_GetError(), handshake_failure);
+        return SECFailure;
+    }
+
+    return SECSuccess;
+
+loser:
+    if (sid) {
+        ss->sec.uncache(sid);
+        ssl_FreeSID(sid);
+    }
+    return SECFailure;
+}
+
+static SECStatus
+tls13_SendHelloRetryRequest(sslSocket *ss, const sslNamedGroupDef *selectedGroup)
+{
+    SECStatus rv;
+
+    SSL_TRC(3, ("%d: TLS13[%d]: send hello retry request handshake",
+                SSL_GETPID(), ss->fd));
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+
+    /* We asked already, but made no progress. */
+    if (ss->ssl3.hs.helloRetry) {
+        FATAL_ERROR(ss, SSL_ERROR_BAD_2ND_CLIENT_HELLO, illegal_parameter);
+        return SECFailure;
+    }
+
+    ssl_GetXmitBufLock(ss);
+    rv = ssl3_AppendHandshakeHeader(ss, hello_retry_request,
+                                    2 +     /* version */
+                                        2 + /* extension length */
+                                        2 + /* group extension id */
+                                        2 + /* group extension length */
+                                        2 /* group */);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+        goto loser;
+    }
+
+    rv = ssl3_AppendHandshakeNumber(
+        ss, tls13_EncodeDraftVersion(ss->version), 2);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+        goto loser;
+    }
+
+    /* Length of extensions. */
+    rv = ssl3_AppendHandshakeNumber(ss, 2 + 2 + 2, 2);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+        goto loser;
+    }
+
+    /* Key share extension - currently the only reason we send this. */
+    rv = ssl3_AppendHandshakeNumber(ss, ssl_tls13_key_share_xtn, 2);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+        goto loser;
+    }
+    /* Key share extension length. */
+    rv = ssl3_AppendHandshakeNumber(ss, 2, 2);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+        goto loser;
+    }
+    rv = ssl3_AppendHandshakeNumber(ss, selectedGroup->name, 2);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+        goto loser;
+    }
+
+    rv = ssl3_FlushHandshake(ss, 0);
+    if (rv != SECSuccess) {
+        goto loser; /* error code set by ssl3_FlushHandshake */
+    }
+    ssl_ReleaseXmitBufLock(ss);
+
+    ss->ssl3.hs.helloRetry = PR_TRUE;
+
+    /* We received early data but have to ignore it because we sent a retry. */
+    if (ss->ssl3.hs.zeroRttState == ssl_0rtt_sent) {
+        ss->ssl3.hs.zeroRttState = ssl_0rtt_ignored;
+        ss->ssl3.hs.zeroRttIgnore = ssl_0rtt_ignore_hrr;
+    }
+
+    return SECSuccess;
+
+loser:
+    ssl_ReleaseXmitBufLock(ss);
+    return SECFailure;
+}
+
+/* Called from tls13_HandleClientHello.
+ *
+ * Caller must hold Handshake and RecvBuf locks.
+ */
+
+static SECStatus
+tls13_HandleClientKeyShare(sslSocket *ss, TLS13KeyShareEntry *peerShare)
+{
+    SECStatus rv;
+    sslEphemeralKeyPair *keyPair; /* ours */
+
+    SSL_TRC(3, ("%d: TLS13[%d]: handle client_key_share handshake",
+                SSL_GETPID(), ss->fd));
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+    PORT_Assert(peerShare);
+
+    tls13_SetKeyExchangeType(ss, peerShare->group);
+
+    /* Generate our key */
+    rv = tls13_CreateKeyShare(ss, peerShare->group);
+    if (rv != SECSuccess) {
+        return rv;
+    }
+
+    /* We should have exactly one key share. */
+    PORT_Assert(!PR_CLIST_IS_EMPTY(&ss->ephemeralKeyPairs));
+    PORT_Assert(PR_PREV_LINK(&ss->ephemeralKeyPairs) ==
+                PR_NEXT_LINK(&ss->ephemeralKeyPairs));
+
+    keyPair = ((sslEphemeralKeyPair *)PR_NEXT_LINK(&ss->ephemeralKeyPairs));
+    ss->sec.keaKeyBits = SECKEY_PublicKeyStrengthInBits(keyPair->keys->pubKey);
+
+    /* Register the sender */
+    rv = ssl3_RegisterExtensionSender(ss, &ss->xtnData, ssl_tls13_key_share_xtn,
+                                      tls13_ServerSendKeyShareXtn);
+    if (rv != SECSuccess) {
+        return SECFailure; /* Error code set already. */
+    }
+
+    rv = tls13_HandleKeyShare(ss, peerShare, keyPair->keys);
+    return rv; /* Error code set already. */
+}
+
+/*
+ *     [draft-ietf-tls-tls13-11] Section 6.3.3.2
+ *
+ *     opaque DistinguishedName<1..2^16-1>;
+ *
+ *     struct {
+ *         opaque certificate_extension_oid<1..2^8-1>;
+ *         opaque certificate_extension_values<0..2^16-1>;
+ *     } CertificateExtension;
+ *
+ *     struct {
+ *         opaque certificate_request_context<0..2^8-1>;
+ *         SignatureAndHashAlgorithm
+ *           supported_signature_algorithms<2..2^16-2>;
+ *         DistinguishedName certificate_authorities<0..2^16-1>;
+ *         CertificateExtension certificate_extensions<0..2^16-1>;
+ *     } CertificateRequest;
+ */
+static SECStatus
+tls13_SendCertificateRequest(sslSocket *ss)
+{
+    SECStatus rv;
+    int calen;
+    SECItem *names;
+    int nnames;
+    SECItem *name;
+    int i;
+    PRUint8 sigSchemes[MAX_SIGNATURE_SCHEMES * 2];
+    unsigned int sigSchemesLength = 0;
+    int length;
+
+    SSL_TRC(3, ("%d: TLS13[%d]: begin send certificate_request",
+                SSL_GETPID(), ss->fd));
+
+    rv = ssl3_EncodeSigAlgs(ss, sigSchemes, sizeof(sigSchemes),
+                            &sigSchemesLength);
+    if (rv != SECSuccess) {
+        return rv;
+    }
+
+    ssl3_GetCertificateRequestCAs(ss, &calen, &names, &nnames);
+    length = 1 + 0 /* length byte for empty request context */ +
+             2 + sigSchemesLength + 2 + calen + 2;
+
+    rv = ssl3_AppendHandshakeHeader(ss, certificate_request, length);
+    if (rv != SECSuccess) {
+        return rv; /* err set by AppendHandshake. */
+    }
+    rv = ssl3_AppendHandshakeNumber(ss, 0, 1);
+    if (rv != SECSuccess) {
+        return rv; /* err set by AppendHandshake. */
+    }
+    rv = ssl3_AppendHandshakeVariable(ss, sigSchemes, sigSchemesLength, 2);
+    if (rv != SECSuccess) {
+        return rv; /* err set by AppendHandshake. */
+    }
+    rv = ssl3_AppendHandshakeNumber(ss, calen, 2);
+    if (rv != SECSuccess) {
+        return rv; /* err set by AppendHandshake. */
+    }
+    for (i = 0, name = names; i < nnames; i++, name++) {
+        rv = ssl3_AppendHandshakeVariable(ss, name->data, name->len, 2);
+        if (rv != SECSuccess) {
+            return rv; /* err set by AppendHandshake. */
+        }
+    }
+    rv = ssl3_AppendHandshakeNumber(ss, 0, 2);
+    if (rv != SECSuccess) {
+        return rv; /* err set by AppendHandshake. */
+    }
+
+    return SECSuccess;
+}
+
+SECStatus
+tls13_HandleHelloRetryRequest(sslSocket *ss, SSL3Opaque *b, PRUint32 length)
+{
+    SECStatus rv;
+    PRInt32 tmp;
+    SSL3ProtocolVersion version;
+
+    SSL_TRC(3, ("%d: TLS13[%d]: handle hello retry request",
+                SSL_GETPID(), ss->fd));
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+
+    if (ss->vrange.max < SSL_LIBRARY_VERSION_TLS_1_3) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_UNEXPECTED_HELLO_RETRY_REQUEST,
+                    unexpected_message);
+        return SECFailure;
+    }
+
+    /* Client only. */
+    rv = TLS13_CHECK_HS_STATE(ss, SSL_ERROR_RX_UNEXPECTED_HELLO_RETRY_REQUEST,
+                              wait_server_hello);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+
+    /* Fool me once, shame on you; fool me twice... */
+    if (ss->ssl3.hs.helloRetry) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_UNEXPECTED_HELLO_RETRY_REQUEST,
+                    unexpected_message);
+        return SECFailure;
+    }
+
+    if (ss->ssl3.hs.zeroRttState == ssl_0rtt_sent) {
+        /* Oh well, back to the start. */
+        tls13_SetNullCipherSpec(ss, &ss->ssl3.cwSpec);
+        ss->ssl3.hs.zeroRttState = ssl_0rtt_ignored;
+    } else {
+        PORT_Assert(ss->ssl3.hs.zeroRttState == ssl_0rtt_none);
+    }
+
+    /* Version. */
+    rv = ssl_ClientReadVersion(ss, &b, &length, &version);
+    if (rv != SECSuccess) {
+        return SECFailure; /* alert already sent */
+    }
+    if (version > ss->vrange.max || version < SSL_LIBRARY_VERSION_TLS_1_3) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_HELLO_RETRY_REQUEST,
+                    protocol_version);
+        return SECFailure;
+    }
+
+    /* Extensions. */
+    tmp = ssl3_ConsumeHandshakeNumber(ss, 2, &b, &length);
+    if (tmp < 0) {
+        return SECFailure; /* error code already set */
+    }
+    /* Extensions must be non-empty and use the remainder of the message.
+     * This means that a HelloRetryRequest cannot be a no-op: we must have an
+     * extension, it must be one that we understand and recognize as being valid
+     * for HelloRetryRequest, and all the extensions we permit cause us to
+     * modify our ClientHello in some way. */
+    if (!tmp || tmp != length) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_HELLO_RETRY_REQUEST,
+                    decode_error);
+        return SECFailure;
+    }
+
+    rv = ssl3_HandleExtensions(ss, &b, &length, hello_retry_request);
+    if (rv != SECSuccess) {
+        return SECFailure; /* Error code set below */
+    }
+
+    ss->ssl3.hs.helloRetry = PR_TRUE;
+
+    ssl_GetXmitBufLock(ss);
+    rv = ssl3_SendClientHello(ss, client_hello_retry);
+    ssl_ReleaseXmitBufLock(ss);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+
+    return SECSuccess;
+}
+
+static SECStatus
+tls13_HandleCertificateRequest(sslSocket *ss, SSL3Opaque *b, PRUint32 length)
+{
+    SECStatus rv;
+    TLS13CertificateRequest *certRequest = NULL;
+    SECItem context = { siBuffer, NULL, 0 };
+    PLArenaPool *arena;
+    PRInt32 extensionsLength;
+
+    SSL_TRC(3, ("%d: TLS13[%d]: handle certificate_request sequence",
+                SSL_GETPID(), ss->fd));
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+
+    /* Client */
+    rv = TLS13_CHECK_HS_STATE(ss, SSL_ERROR_RX_UNEXPECTED_CERT_REQUEST,
+                              wait_cert_request);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+
+    PORT_Assert(ss->ssl3.clientCertChain == NULL);
+    PORT_Assert(ss->ssl3.clientCertificate == NULL);
+    PORT_Assert(ss->ssl3.clientPrivateKey == NULL);
+    PORT_Assert(ss->ssl3.hs.certificateRequest == NULL);
+
+    arena = PORT_NewArena(DER_DEFAULT_CHUNKSIZE);
+    if (!arena) {
+        FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+        return SECFailure;
+    }
+
+    rv = ssl3_ConsumeHandshakeVariable(ss, &context, 1, &b, &length);
+    if (rv != SECSuccess)
+        goto loser;
+
+    /* We don't support post-handshake client auth, the certificate request
+     * context must always be null. */
+    if (context.len > 0) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_CERT_REQUEST, illegal_parameter);
+        goto loser;
+    }
+
+    certRequest = PORT_ArenaZNew(arena, TLS13CertificateRequest);
+    if (!certRequest)
+        goto loser;
+    certRequest->arena = arena;
+    certRequest->ca_list.arena = arena;
+
+    rv = ssl_ParseSignatureSchemes(ss, arena,
+                                   &certRequest->signatureSchemes,
+                                   &certRequest->signatureSchemeCount,
+                                   &b, &length);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_CERT_REQUEST,
+                    decode_error);
+        goto loser;
+    }
+
+    rv = ssl3_ParseCertificateRequestCAs(ss, &b, &length, arena,
+                                         &certRequest->ca_list);
+    if (rv != SECSuccess)
+        goto loser; /* alert already sent */
+
+    /* Verify that the extensions length is correct. */
+    extensionsLength = ssl3_ConsumeHandshakeNumber(ss, 2, &b, &length);
+    if (extensionsLength < 0) {
+        goto loser; /* alert already sent */
+    }
+    if (extensionsLength != length) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_CERT_REQUEST,
+                    illegal_parameter);
+        goto loser;
+    }
+
+    rv = SECITEM_CopyItem(arena, &certRequest->context, &context);
+    if (rv != SECSuccess)
+        goto loser;
+
+    TLS13_SET_HS_STATE(ss, wait_server_cert);
+    ss->ssl3.hs.certificateRequest = certRequest;
+
+    return SECSuccess;
+
+loser:
+    PORT_FreeArena(arena, PR_FALSE);
+    return SECFailure;
+}
+
+static SECStatus
+tls13_SendEncryptedServerSequence(sslSocket *ss)
+{
+    SECStatus rv;
+
+    rv = tls13_ComputeHandshakeSecrets(ss);
+    if (rv != SECSuccess) {
+        return SECFailure; /* error code is set. */
+    }
+
+    rv = tls13_SetCipherSpec(ss, TrafficKeyHandshake,
+                             CipherSpecWrite, PR_FALSE);
+    if (rv != SECSuccess) {
+        LOG_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE);
+        return SECFailure;
+    }
+
+    ss->ssl3.hs.shortHeaders = ssl3_ExtensionNegotiated(
+        ss, ssl_tls13_short_header_xtn);
+
+    if (ss->ssl3.hs.zeroRttState == ssl_0rtt_accepted) {
+        rv = ssl3_RegisterExtensionSender(ss, &ss->xtnData, ssl_tls13_early_data_xtn,
+                                          tls13_ServerSendEarlyDataXtn);
+        if (rv != SECSuccess) {
+            return SECFailure; /* Error code set already. */
+        }
+    }
+
+    rv = tls13_SendEncryptedExtensions(ss);
+    if (rv != SECSuccess) {
+        return SECFailure; /* error code is set. */
+    }
+
+    if (ss->opt.requestCertificate) {
+        rv = tls13_SendCertificateRequest(ss);
+        if (rv != SECSuccess) {
+            return SECFailure; /* error code is set. */
+        }
+    }
+    if (ss->ssl3.hs.signatureScheme != ssl_sig_none) {
+        SECKEYPrivateKey *svrPrivKey;
+
+        rv = tls13_SendCertificate(ss);
+        if (rv != SECSuccess) {
+            return SECFailure; /* error code is set. */
+        }
+
+        svrPrivKey = ss->sec.serverCert->serverKeyPair->privKey;
+        rv = tls13_SendCertificateVerify(ss, svrPrivKey);
+        if (rv != SECSuccess) {
+            return SECFailure; /* err code is set. */
+        }
+    }
+
+    rv = tls13_SendFinished(ss, ss->ssl3.hs.serverHsTrafficSecret);
+    if (rv != SECSuccess) {
+        return SECFailure; /* error code is set. */
+    }
+
+    return SECSuccess;
+}
+
+/* Called from:  ssl3_HandleClientHello */
+static SECStatus
+tls13_SendServerHelloSequence(sslSocket *ss)
+{
+    SECStatus rv;
+    PRErrorCode err = 0;
+
+    SSL_TRC(3, ("%d: TLS13[%d]: begin send server_hello sequence",
+                SSL_GETPID(), ss->fd));
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveXmitBufLock(ss));
+
+    rv = ssl3_SendServerHello(ss);
+    if (rv != SECSuccess) {
+        return rv; /* err code is set. */
+    }
+
+    rv = tls13_SendEncryptedServerSequence(ss);
+    if (rv != SECSuccess) {
+        err = PORT_GetError();
+    }
+    /* Even if we get an error, since the ServerHello was successfully
+     * serialized, we should give it a chance to reach the network.  This gives
+     * the client a chance to perform the key exchange and decrypt the alert
+     * we're about to send. */
+    rv |= ssl3_FlushHandshake(ss, 0);
+    if (rv != SECSuccess) {
+        if (err) {
+            PORT_SetError(err);
+        }
+        return SECFailure;
+    }
+
+    /* Compute the rest of the secrets except for the resumption
+     * and exporter secret. */
+    rv = tls13_ComputeApplicationSecrets(ss);
+    if (rv != SECSuccess) {
+        LOG_ERROR(ss, PORT_GetError());
+        return SECFailure;
+    }
+
+    rv = tls13_SetCipherSpec(ss, TrafficKeyApplicationData,
+                             CipherSpecWrite, PR_FALSE);
+    if (rv != SECSuccess) {
+        LOG_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE);
+        return SECFailure;
+    }
+
+    if (ss->ssl3.hs.zeroRttState == ssl_0rtt_accepted) {
+        rv = tls13_SetCipherSpec(ss,
+                                 TrafficKeyEarlyApplicationData,
+                                 CipherSpecRead, PR_TRUE);
+        if (rv != SECSuccess) {
+            LOG_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE);
+            return SECFailure;
+        }
+    } else {
+        PORT_Assert(ss->ssl3.hs.zeroRttState == ssl_0rtt_none ||
+                    ss->ssl3.hs.zeroRttState == ssl_0rtt_ignored);
+
+        rv = tls13_SetCipherSpec(ss,
+                                 TrafficKeyHandshake,
+                                 CipherSpecRead, PR_FALSE);
+        if (rv != SECSuccess) {
+            LOG_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE);
+            return SECFailure;
+        }
+    }
+
+    TLS13_SET_HS_STATE(ss,
+                       ss->opt.requestCertificate ? wait_client_cert
+                                                  : wait_finished);
+    return SECSuccess;
+}
+
+SECStatus
+tls13_HandleServerHelloPart2(sslSocket *ss)
+{
+    SECStatus rv;
+    sslSessionID *sid = ss->sec.ci.sid;
+    SSL3Statistics *ssl3stats = SSL_GetStatistics();
+
+    if (ssl3_ExtensionNegotiated(ss, ssl_tls13_pre_shared_key_xtn)) {
+        PORT_Assert(ss->statelessResume);
+    } else {
+        if (ss->ssl3.hs.currentSecret) {
+            PORT_Assert(ss->statelessResume);
+            PK11_FreeSymKey(ss->ssl3.hs.currentSecret);
+            ss->ssl3.hs.currentSecret = NULL;
+        }
+        ss->statelessResume = PR_FALSE;
+    }
+
+    if (ss->statelessResume) {
+        if (tls13_GetHash(ss) !=
+            tls13_GetHashForCipherSuite(sid->u.ssl3.cipherSuite)) {
+            FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_SERVER_HELLO,
+                        illegal_parameter);
+            return SECFailure;
+        }
+    }
+
+    /* Now create a synthetic kea_def that we can tweak. */
+    ss->ssl3.hs.kea_def_mutable = *ss->ssl3.hs.kea_def;
+    ss->ssl3.hs.kea_def = &ss->ssl3.hs.kea_def_mutable;
+
+    if (ss->statelessResume) {
+        /* PSK */
+        ss->ssl3.hs.kea_def_mutable.authKeyType = ssl_auth_psk;
+        tls13_RestoreCipherInfo(ss, sid);
+        if (sid->peerCert) {
+            ss->sec.peerCert = CERT_DupCertificate(sid->peerCert);
+        }
+
+        SSL_AtomicIncrementLong(&ssl3stats->hsh_sid_cache_hits);
+        SSL_AtomicIncrementLong(&ssl3stats->hsh_sid_stateless_resumes);
+    } else {
+        /* !PSK */
+        if (ssl3_ClientExtensionAdvertised(ss, ssl_tls13_pre_shared_key_xtn)) {
+            SSL_AtomicIncrementLong(&ssl3stats->hsh_sid_cache_misses);
+        }
+        if (sid->cached == in_client_cache) {
+            /* If we tried to resume and failed, let's not try again. */
+            ss->sec.uncache(sid);
+        }
+    }
+
+    if (!ss->ssl3.hs.currentSecret) {
+        PORT_Assert(!ss->statelessResume);
+
+        /* If we don't already have the Early Secret we need to make it
+         * now. */
+        rv = tls13_ComputeEarlySecrets(ss);
+        if (rv != SECSuccess) {
+            FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+            return SECFailure;
+        }
+    }
+
+    /* Discard current SID and make a new one, though it may eventually
+     * end up looking a lot like the old one.
+     */
+    ssl_FreeSID(sid);
+    ss->sec.ci.sid = sid = ssl3_NewSessionID(ss, PR_FALSE);
+    if (sid == NULL) {
+        FATAL_ERROR(ss, PORT_GetError(), internal_error);
+        return SECFailure;
+    }
+    if (ss->statelessResume) {
+        PORT_Assert(ss->sec.peerCert);
+        sid->peerCert = CERT_DupCertificate(ss->sec.peerCert);
+    }
+    sid->version = ss->version;
+
+    rv = tls13_HandleServerKeyShare(ss);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+    rv = tls13_ComputeHandshakeSecrets(ss);
+    if (rv != SECSuccess) {
+        return SECFailure; /* error code is set. */
+    }
+
+    ss->ssl3.hs.shortHeaders = ssl3_ExtensionNegotiated(
+        ss, ssl_tls13_short_header_xtn);
+
+    rv = tls13_SetCipherSpec(ss, TrafficKeyHandshake,
+                             CipherSpecRead, PR_FALSE);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SSL_ERROR_INIT_CIPHER_SUITE_FAILURE, internal_error);
+        return SECFailure;
+    }
+    TLS13_SET_HS_STATE(ss, wait_encrypted_extensions);
+
+    return SECSuccess;
+}
+
+static void
+tls13_SetKeyExchangeType(sslSocket *ss, const sslNamedGroupDef *group)
+{
+    ss->sec.keaGroup = group;
+    switch (group->keaType) {
+        /* Note: These overwrite on resumption.... so if you start with ECDH
+         * and resume with DH, we report DH. That's fine, since no answer
+         * is really right. */
+        case ssl_kea_ecdh:
+            ss->ssl3.hs.kea_def_mutable.exchKeyType =
+                ss->statelessResume ? ssl_kea_ecdh_psk : ssl_kea_ecdh;
+            ss->sec.keaType = ssl_kea_ecdh;
+            break;
+        case ssl_kea_dh:
+            ss->ssl3.hs.kea_def_mutable.exchKeyType =
+                ss->statelessResume ? ssl_kea_dh_psk : ssl_kea_dh;
+            ss->sec.keaType = ssl_kea_dh;
+            break;
+        default:
+            PORT_Assert(0);
+    }
+}
+
+/*
+ * Called from ssl3_HandleServerHello.
+ *
+ * Caller must hold Handshake and RecvBuf locks.
+ */
+static SECStatus
+tls13_HandleServerKeyShare(sslSocket *ss)
+{
+    SECStatus rv;
+    TLS13KeyShareEntry *entry;
+    sslEphemeralKeyPair *keyPair;
+
+    SSL_TRC(3, ("%d: TLS13[%d]: handle server_key_share handshake",
+                SSL_GETPID(), ss->fd));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+
+    /* This list should have one entry. */
+    if (PR_CLIST_IS_EMPTY(&ss->xtnData.remoteKeyShares)) {
+        FATAL_ERROR(ss, SSL_ERROR_MISSING_KEY_SHARE, missing_extension);
+        return SECFailure;
+    }
+
+    entry = (TLS13KeyShareEntry *)PR_NEXT_LINK(&ss->xtnData.remoteKeyShares);
+    PORT_Assert(PR_NEXT_LINK(&entry->link) == &ss->xtnData.remoteKeyShares);
+
+    /* Now get our matching key. */
+    keyPair = ssl_LookupEphemeralKeyPair(ss, entry->group);
+    if (!keyPair) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_KEY_SHARE, illegal_parameter);
+        return SECFailure;
+    }
+
+    PORT_Assert(ssl_NamedGroupEnabled(ss, entry->group));
+
+    rv = tls13_HandleKeyShare(ss, entry, keyPair->keys);
+    if (rv != SECSuccess)
+        return SECFailure; /* Error code set by caller. */
+
+    tls13_SetKeyExchangeType(ss, entry->group);
+    ss->sec.keaKeyBits = SECKEY_PublicKeyStrengthInBits(keyPair->keys->pubKey);
+
+    return SECSuccess;
+}
+
+/*
+ *    opaque ASN1Cert<1..2^24-1>;
+ *
+ *    struct {
+ *        ASN1Cert cert_data;
+ *        Extension extensions<0..2^16-1>;
+ *    } CertificateEntry;
+ *
+ *    struct {
+ *        opaque certificate_request_context<0..2^8-1>;
+ *        CertificateEntry certificate_list<0..2^24-1>;
+ *    } Certificate;
+ */
+static SECStatus
+tls13_SendCertificate(sslSocket *ss)
+{
+    SECStatus rv;
+    CERTCertificateList *certChain;
+    int certChainLen = 0;
+    int i;
+    SECItem context = { siBuffer, NULL, 0 };
+    PRInt32 extensionsLen = 0;
+    PRUint32 maxBytes = 65535;
+
+    SSL_TRC(3, ("%d: TLS1.3[%d]: send certificate handshake",
+                SSL_GETPID(), ss->fd));
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveXmitBufLock(ss));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+
+    if (ss->sec.isServer) {
+        PORT_Assert(!ss->sec.localCert);
+        /* A server certificate is selected in tls13_SelectServerCert(). */
+        PORT_Assert(ss->sec.serverCert);
+
+        certChain = ss->sec.serverCert->serverCertChain;
+        ss->sec.localCert = CERT_DupCertificate(ss->sec.serverCert->serverCert);
+    } else {
+        if (ss->sec.localCert)
+            CERT_DestroyCertificate(ss->sec.localCert);
+
+        certChain = ss->ssl3.clientCertChain;
+        ss->sec.localCert = CERT_DupCertificate(ss->ssl3.clientCertificate);
+    }
+
+    /* Get the extensions length. This only applies to the leaf cert,
+     * because we don't yet send extensions for non-leaf certs. */
+    extensionsLen = ssl3_CallHelloExtensionSenders(
+        ss, PR_FALSE, maxBytes, &ss->xtnData.certificateSenders[0]);
+
+    if (!ss->sec.isServer) {
+        PORT_Assert(ss->ssl3.hs.certificateRequest);
+        context = ss->ssl3.hs.certificateRequest->context;
+    }
+    if (certChain) {
+        for (i = 0; i < certChain->len; i++) {
+            certChainLen +=
+                3 + certChain->certs[i].len + /* cert length + cert */
+                2 + (!i ? extensionsLen : 0); /* extensions length + extensions */
+        }
+    }
+
+    rv = ssl3_AppendHandshakeHeader(ss, certificate,
+                                    1 + context.len +
+                                        3 + certChainLen);
+    if (rv != SECSuccess) {
+        return SECFailure; /* err set by AppendHandshake. */
+    }
+
+    rv = ssl3_AppendHandshakeVariable(ss, context.data,
+                                      context.len, 1);
+    if (rv != SECSuccess) {
+        return SECFailure; /* err set by AppendHandshake. */
+    }
+
+    rv = ssl3_AppendHandshakeNumber(ss, certChainLen, 3);
+    if (rv != SECSuccess) {
+        return SECFailure; /* err set by AppendHandshake. */
+    }
+    if (certChain) {
+        for (i = 0; i < certChain->len; i++) {
+            PRInt32 sentLen;
+
+            rv = ssl3_AppendHandshakeVariable(ss, certChain->certs[i].data,
+                                              certChain->certs[i].len, 3);
+            if (rv != SECSuccess) {
+                return SECFailure; /* err set by AppendHandshake. */
+            }
+
+            if (i) {
+                /* Not end-entity. */
+                rv = ssl3_AppendHandshakeNumber(ss, 0, 2);
+                if (rv != SECSuccess) {
+                    return SECFailure; /* err set by AppendHandshake. */
+                }
+                continue;
+            }
+
+            /* End-entity, send extensions. */
+            rv = ssl3_AppendHandshakeNumber(ss, extensionsLen, 2);
+            if (rv != SECSuccess) {
+                return SECFailure; /* err set by AppendHandshake. */
+            }
+
+            sentLen = ssl3_CallHelloExtensionSenders(
+                ss, PR_TRUE, extensionsLen,
+                &ss->xtnData.certificateSenders[0]);
+            PORT_Assert(sentLen == extensionsLen);
+            if (sentLen != extensionsLen) {
+                LOG_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE);
+                return SECFailure;
+            }
+        }
+    }
+
+    return SECSuccess;
+}
+
+static SECStatus
+tls13_HandleCertificateEntry(sslSocket *ss, SECItem *data, PRBool first,
+                             CERTCertificate **certp)
+{
+    SECStatus rv;
+    SECItem certData;
+    SECItem extensionsData;
+    CERTCertificate *cert = NULL;
+
+    rv = ssl3_ConsumeHandshakeVariable(ss, &certData,
+                                       3, &data->data, &data->len);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+
+    rv = ssl3_ConsumeHandshakeVariable(ss, &extensionsData,
+                                       2, &data->data, &data->len);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+
+    /* Parse all the extensions. */
+    if (first && !ss->sec.isServer) {
+        rv = ssl3_HandleExtensions(ss, &extensionsData.data,
+                                   &extensionsData.len,
+                                   certificate);
+        if (rv != SECSuccess) {
+            return SECFailure;
+        }
+
+        /* TODO(ekr@rtfm.com): Copy out SCTs. Bug 1315727. */
+    }
+
+    cert = CERT_NewTempCertificate(ss->dbHandle, &certData, NULL,
+                                   PR_FALSE, PR_TRUE);
+
+    if (!cert) {
+        PRErrorCode errCode = PORT_GetError();
+        switch (errCode) {
+            case PR_OUT_OF_MEMORY_ERROR:
+            case SEC_ERROR_BAD_DATABASE:
+            case SEC_ERROR_NO_MEMORY:
+                FATAL_ERROR(ss, errCode, internal_error);
+                return SECFailure;
+            default:
+                ssl3_SendAlertForCertError(ss, errCode);
+                return SECFailure;
+        }
+    }
+
+    *certp = cert;
+
+    return SECSuccess;
+}
+
+/* Called from tls13_CompleteHandleHandshakeMessage() when it has deciphered a complete
+ * tls13 Certificate message.
+ * Caller must hold Handshake and RecvBuf locks.
+ */
+static SECStatus
+tls13_HandleCertificate(sslSocket *ss, SSL3Opaque *b, PRUint32 length)
+{
+    SECStatus rv;
+    SECItem context = { siBuffer, NULL, 0 };
+    SECItem certList;
+    PRBool first = PR_TRUE;
+    ssl3CertNode *lastCert = NULL;
+
+    SSL_TRC(3, ("%d: TLS13[%d]: handle certificate handshake",
+                SSL_GETPID(), ss->fd));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+
+    if (ss->sec.isServer) {
+        rv = TLS13_CHECK_HS_STATE(ss, SSL_ERROR_RX_UNEXPECTED_CERTIFICATE,
+                                  wait_client_cert);
+    } else {
+        rv = TLS13_CHECK_HS_STATE(ss, SSL_ERROR_RX_UNEXPECTED_CERTIFICATE,
+                                  wait_cert_request, wait_server_cert);
+    }
+    if (rv != SECSuccess)
+        return SECFailure;
+
+    /* Process the context string */
+    rv = ssl3_ConsumeHandshakeVariable(ss, &context, 1, &b, &length);
+    if (rv != SECSuccess)
+        return SECFailure;
+
+    if (context.len) {
+        /* The context string MUST be empty */
+        FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_CERTIFICATE, illegal_parameter);
+        return SECFailure;
+    }
+
+    rv = ssl3_ConsumeHandshakeVariable(ss, &certList, 3, &b, &length);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+    if (length) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_CERTIFICATE, illegal_parameter);
+        return SECFailure;
+    }
+
+    if (!certList.len) {
+        if (!ss->sec.isServer) {
+            /* Servers always need to send some cert. */
+            FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_CERTIFICATE, bad_certificate);
+            return SECFailure;
+        } else {
+            /* This is TLS's version of a no_certificate alert. */
+            /* I'm a server. I've requested a client cert. He hasn't got one. */
+            rv = ssl3_HandleNoCertificate(ss);
+            if (rv != SECSuccess) {
+                return SECFailure;
+            }
+
+            TLS13_SET_HS_STATE(ss, wait_finished);
+            return SECSuccess;
+        }
+    }
+
+    /* Now clean up. */
+    ssl3_CleanupPeerCerts(ss);
+    ss->ssl3.peerCertArena = PORT_NewArena(DER_DEFAULT_CHUNKSIZE);
+    if (ss->ssl3.peerCertArena == NULL) {
+        FATAL_ERROR(ss, SEC_ERROR_NO_MEMORY, internal_error);
+        return SECFailure;
+    }
+
+    while (certList.len) {
+        CERTCertificate *cert;
+
+        rv = tls13_HandleCertificateEntry(ss, &certList, first,
+                                          &cert);
+        if (rv != SECSuccess) {
+            ss->xtnData.signedCertTimestamps.len = 0;
+            return SECFailure;
+        }
+
+        if (first) {
+            ss->sec.peerCert = cert;
+
+            if (ss->xtnData.signedCertTimestamps.len) {
+                sslSessionID *sid = ss->sec.ci.sid;
+                rv = SECITEM_CopyItem(NULL, &sid->u.ssl3.signedCertTimestamps,
+                                      &ss->xtnData.signedCertTimestamps);
+                ss->xtnData.signedCertTimestamps.len = 0;
+                if (rv != SECSuccess) {
+                    FATAL_ERROR(ss, SEC_ERROR_NO_MEMORY, internal_error);
+                    return SECFailure;
+                }
+            }
+        } else {
+            ssl3CertNode *c = PORT_ArenaNew(ss->ssl3.peerCertArena,
+                                            ssl3CertNode);
+            if (!c) {
+                FATAL_ERROR(ss, SEC_ERROR_NO_MEMORY, internal_error);
+                return SECFailure;
+            }
+            c->cert = cert;
+            c->next = NULL;
+
+            if (lastCert) {
+                lastCert->next = c;
+            } else {
+                ss->ssl3.peerCertChain = c;
+            }
+            lastCert = c;
+        }
+
+        first = PR_FALSE;
+    }
+    SECKEY_UpdateCertPQG(ss->sec.peerCert);
+
+    return ssl3_AuthCertificate(ss); /* sets ss->ssl3.hs.ws */
+}
+
+void
+tls13_CipherSpecAddRef(ssl3CipherSpec *spec)
+{
+    ++spec->refCt;
+    SSL_TRC(10, ("%d: TLS13[-]: Increment ref ct for spec %d. new ct = %d",
+                 SSL_GETPID(), spec, spec->refCt));
+}
+
+/* This function is never called on a spec which is on the
+ * cipherSpecs list. */
+void
+tls13_CipherSpecRelease(ssl3CipherSpec *spec)
+{
+    PORT_Assert(spec->refCt > 0);
+    --spec->refCt;
+    SSL_TRC(10, ("%d: TLS13[-]: decrement refct for spec %d. phase=%s new ct = %d",
+                 SSL_GETPID(), spec, spec->phase, spec->refCt));
+    if (!spec->refCt) {
+        SSL_TRC(10, ("%d: TLS13[-]: Freeing spec %d. phase=%s",
+                     SSL_GETPID(), spec, spec->phase));
+        PR_REMOVE_LINK(&spec->link);
+        ssl3_DestroyCipherSpec(spec, PR_TRUE);
+        PORT_Free(spec);
+    }
+}
+
+/* Add context to the hash functions as described in
+   [draft-ietf-tls-tls13; Section 4.9.1] */
+SECStatus
+tls13_AddContextToHashes(sslSocket *ss, const SSL3Hashes *hashes,
+                         SSLHashType algorithm, PRBool sending,
+                         SSL3Hashes *tbsHash)
+{
+    SECStatus rv = SECSuccess;
+    PK11Context *ctx;
+    const unsigned char context_padding[] = {
+        0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+        0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+        0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+        0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+        0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+        0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+        0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+        0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+    };
+
+    const char *client_cert_verify_string = "TLS 1.3, client CertificateVerify";
+    const char *server_cert_verify_string = "TLS 1.3, server CertificateVerify";
+    const char *context_string = (sending ^ ss->sec.isServer) ? client_cert_verify_string
+                                                              : server_cert_verify_string;
+    unsigned int hashlength;
+
+    /* Double check that we are doing the same hash.*/
+    PORT_Assert(hashes->len == tls13_GetHashSize(ss));
+
+    ctx = PK11_CreateDigestContext(ssl3_HashTypeToOID(algorithm));
+    if (!ctx) {
+        PORT_SetError(SEC_ERROR_NO_MEMORY);
+        goto loser;
+    }
+
+    PORT_Assert(SECFailure);
+    PORT_Assert(!SECSuccess);
+
+    PRINT_BUF(50, (ss, "TLS 1.3 hash without context", hashes->u.raw, hashes->len));
+    PRINT_BUF(50, (ss, "Context string", context_string, strlen(context_string)));
+    rv |= PK11_DigestBegin(ctx);
+    rv |= PK11_DigestOp(ctx, context_padding, sizeof(context_padding));
+    rv |= PK11_DigestOp(ctx, (unsigned char *)context_string,
+                        strlen(context_string) + 1); /* +1 includes the terminating 0 */
+    rv |= PK11_DigestOp(ctx, hashes->u.raw, hashes->len);
+    /* Update the hash in-place */
+    rv |= PK11_DigestFinal(ctx, tbsHash->u.raw, &hashlength, sizeof(tbsHash->u.raw));
+    PK11_DestroyContext(ctx, PR_TRUE);
+    PRINT_BUF(50, (ss, "TLS 1.3 hash with context", tbsHash->u.raw, hashlength));
+
+    tbsHash->len = hashlength;
+    tbsHash->hashAlg = algorithm;
+
+    if (rv) {
+        ssl_MapLowLevelError(SSL_ERROR_SHA_DIGEST_FAILURE);
+        goto loser;
+    }
+    return SECSuccess;
+
+loser:
+    return SECFailure;
+}
+
+/*
+ *    Derive-Secret(Secret, Label, Messages) =
+ *       HKDF-Expand-Label(Secret, Label,
+ *                         Hash(Messages) + Hash(resumption_context), L))
+ */
+static SECStatus
+tls13_DeriveSecret(sslSocket *ss, PK11SymKey *key,
+                   const char *prefix,
+                   const char *suffix,
+                   const SSL3Hashes *hashes,
+                   PK11SymKey **dest)
+{
+    SECStatus rv;
+    SSL3Hashes hashesTmp;
+    char buf[100];
+    const char *label;
+
+    if (prefix) {
+        if ((strlen(prefix) + strlen(suffix) + 2) > sizeof(buf)) {
+            PORT_Assert(0);
+            PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
+            return SECFailure;
+        }
+        (void)PR_snprintf(buf, sizeof(buf), "%s %s",
+                          prefix, suffix);
+        label = buf;
+    } else {
+        label = suffix;
+    }
+
+    SSL_TRC(3, ("%d: TLS13[%d]: deriving secret '%s'",
+                SSL_GETPID(), ss->fd, label));
+    if (!hashes) {
+        rv = tls13_ComputeHandshakeHashes(ss, &hashesTmp);
+        if (rv != SECSuccess) {
+            PORT_Assert(0); /* Should never fail */
+            ssl_MapLowLevelError(SEC_ERROR_LIBRARY_FAILURE);
+            return SECFailure;
+        }
+        hashes = &hashesTmp;
+    }
+
+    rv = tls13_HkdfExpandLabel(key, tls13_GetHash(ss),
+                               hashes->u.raw, hashes->len,
+                               label, strlen(label),
+                               tls13_GetHkdfMechanism(ss),
+                               tls13_GetHashSize(ss), dest);
+    if (rv != SECSuccess) {
+        LOG_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE);
+        return SECFailure;
+    }
+    return SECSuccess;
+}
+
+/* Derive traffic keys for the next cipher spec in the queue. */
+static SECStatus
+tls13_DeriveTrafficKeys(sslSocket *ss, ssl3CipherSpec *spec,
+                        TrafficKeyType type,
+                        CipherSpecDirection direction,
+                        PRBool deleteSecret)
+{
+    size_t keySize = spec->cipher_def->key_size;
+    size_t ivSize = spec->cipher_def->iv_size +
+                    spec->cipher_def->explicit_nonce_size; /* This isn't always going to
+                                                              * work, but it does for
+                                                              * AES-GCM */
+    CK_MECHANISM_TYPE bulkAlgorithm = ssl3_Alg2Mech(spec->cipher_def->calg);
+    PK11SymKey **prkp = NULL;
+    PK11SymKey *prk = NULL;
+    PRBool clientKey;
+    ssl3KeyMaterial *target;
+    const char *phase;
+    SECStatus rv;
+    /* These labels are just used for debugging. */
+    static const char kHkdfPhaseEarlyApplicationDataKeys[] = "early application data";
+    static const char kHkdfPhaseHandshakeKeys[] = "handshake data";
+    static const char kHkdfPhaseApplicationDataKeys[] = "application data";
+
+    if (ss->sec.isServer ^ (direction == CipherSpecWrite)) {
+        clientKey = PR_TRUE;
+        target = &spec->client;
+    } else {
+        clientKey = PR_FALSE;
+        target = &spec->server;
+    }
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+
+    switch (type) {
+        case TrafficKeyEarlyApplicationData:
+            PORT_Assert(clientKey);
+            phase = kHkdfPhaseEarlyApplicationDataKeys;
+            prkp = &ss->ssl3.hs.clientEarlyTrafficSecret;
+            break;
+        case TrafficKeyHandshake:
+            phase = kHkdfPhaseHandshakeKeys;
+            prkp = clientKey ? &ss->ssl3.hs.clientHsTrafficSecret : &ss->ssl3.hs.serverHsTrafficSecret;
+            break;
+        case TrafficKeyApplicationData:
+            phase = kHkdfPhaseApplicationDataKeys;
+            prkp = clientKey ? &ss->ssl3.hs.clientTrafficSecret : &ss->ssl3.hs.serverTrafficSecret;
+            break;
+        default:
+            LOG_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE);
+            PORT_Assert(0);
+            return SECFailure;
+    }
+    PORT_Assert(prkp != NULL);
+    prk = *prkp;
+
+    SSL_TRC(3, ("%d: TLS13[%d]: deriving %s traffic keys phase='%s'",
+                SSL_GETPID(), ss->fd,
+                (direction == CipherSpecWrite) ? "write" : "read", phase));
+    PORT_Assert(phase);
+    spec->phase = phase;
+
+    rv = tls13_HkdfExpandLabel(prk, tls13_GetHash(ss),
+                               NULL, 0,
+                               kHkdfPurposeKey, strlen(kHkdfPurposeKey),
+                               bulkAlgorithm, keySize,
+                               &target->write_key);
+    if (rv != SECSuccess) {
+        LOG_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE);
+        PORT_Assert(0);
+        goto loser;
+    }
+
+    rv = tls13_HkdfExpandLabelRaw(prk, tls13_GetHash(ss),
+                                  NULL, 0,
+                                  kHkdfPurposeIv, strlen(kHkdfPurposeIv),
+                                  target->write_iv, ivSize);
+    if (rv != SECSuccess) {
+        LOG_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE);
+        PORT_Assert(0);
+        goto loser;
+    }
+
+    if (deleteSecret) {
+        PK11_FreeSymKey(prk);
+        *prkp = NULL;
+    }
+    return SECSuccess;
+
+loser:
+    return SECFailure;
+}
+
+static SECStatus
+tls13_SetupPendingCipherSpec(sslSocket *ss)
+{
+    ssl3CipherSpec *pSpec;
+    ssl3CipherSuite suite = ss->ssl3.hs.cipher_suite;
+    const ssl3BulkCipherDef *bulk = ssl_GetBulkCipherDef(
+        ssl_LookupCipherSuiteDef(suite));
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+
+    ssl_GetSpecWriteLock(ss); /*******************************/
+
+    pSpec = ss->ssl3.pwSpec;
+    /* Version isn't set when we send 0-RTT data. */
+    pSpec->version = PR_MAX(SSL_LIBRARY_VERSION_TLS_1_3, ss->version);
+
+    SSL_TRC(3, ("%d: TLS13[%d]: Set Pending Cipher Suite to 0x%04x",
+                SSL_GETPID(), ss->fd, suite));
+    pSpec->cipher_def = bulk;
+
+    ssl_ReleaseSpecWriteLock(ss); /*******************************/
+    return SECSuccess;
+}
+
+/* Install a new cipher spec for this direction. */
+static SECStatus
+tls13_SetCipherSpec(sslSocket *ss, TrafficKeyType type,
+                    CipherSpecDirection direction, PRBool deleteSecret)
+{
+    SECStatus rv;
+    ssl3CipherSpec *spec = NULL;
+    ssl3CipherSpec **specp = (direction == CipherSpecRead) ? &ss->ssl3.crSpec : &ss->ssl3.cwSpec;
+    /* Flush out old handshake data. */
+    ssl_GetXmitBufLock(ss);
+    rv = ssl3_FlushHandshake(ss, ssl_SEND_FLAG_FORCE_INTO_BUFFER);
+    ssl_ReleaseXmitBufLock(ss);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+
+    /* Create the new spec. */
+    spec = PORT_ZNew(ssl3CipherSpec);
+    if (!spec) {
+        PORT_SetError(SEC_ERROR_NO_MEMORY);
+        return SECFailure;
+    }
+    spec->refCt = 1;
+    PR_APPEND_LINK(&spec->link, &ss->ssl3.hs.cipherSpecs);
+    ss->ssl3.pwSpec = ss->ssl3.prSpec = spec;
+
+    rv = tls13_SetupPendingCipherSpec(ss);
+    if (rv != SECSuccess)
+        return SECFailure;
+
+    switch (spec->cipher_def->calg) {
+        case calg_aes_gcm:
+            spec->aead = tls13_AESGCM;
+            break;
+        case calg_chacha20:
+            spec->aead = tls13_ChaCha20Poly1305;
+            break;
+        default:
+            PORT_Assert(0);
+            return SECFailure;
+            break;
+    }
+
+    rv = tls13_DeriveTrafficKeys(ss, spec, type, direction,
+                                 deleteSecret);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+
+    /* We use the epoch for cipher suite identification, so increment
+     * it in both TLS and DTLS. */
+    if ((*specp)->epoch == PR_UINT16_MAX) {
+        return SECFailure;
+    }
+    spec->epoch = (*specp)->epoch + 1;
+
+    if (!IS_DTLS(ss)) {
+        spec->read_seq_num = spec->write_seq_num = 0;
+    } else {
+        /* The sequence number has the high 16 bits as the epoch. */
+        spec->read_seq_num = spec->write_seq_num =
+            (sslSequenceNumber)spec->epoch << 48;
+
+        dtls_InitRecvdRecords(&spec->recvdRecords);
+    }
+
+    /* Now that we've set almost everything up, finally cut over. */
+    ssl_GetSpecWriteLock(ss);
+    tls13_CipherSpecRelease(*specp); /* May delete old cipher. */
+    *specp = spec;                   /* Overwrite. */
+    ssl_ReleaseSpecWriteLock(ss);
+
+    SSL_TRC(3, ("%d: TLS13[%d]: %s installed key for phase='%s'.%d dir=%s",
+                SSL_GETPID(), ss->fd, SSL_ROLE(ss),
+                spec->phase, spec->epoch,
+                direction == CipherSpecRead ? "read" : "write"));
+
+    return SECSuccess;
+}
+
+static SECStatus
+tls13_ComputeHandshakeHashes(sslSocket *ss,
+                             SSL3Hashes *hashes)
+{
+    SECStatus rv;
+    PK11Context *ctx = NULL;
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+    if (ss->ssl3.hs.hashType == handshake_hash_unknown) {
+        /* Backup: if we haven't done any hashing, then hash now.
+         * This happens when we are doing 0-RTT on the client. */
+        ctx = PK11_CreateDigestContext(ssl3_HashTypeToOID(tls13_GetHash(ss)));
+        if (!ctx) {
+            ssl_MapLowLevelError(SSL_ERROR_SHA_DIGEST_FAILURE);
+            return SECFailure;
+        }
+
+        if (PK11_DigestBegin(ctx) != SECSuccess) {
+            ssl_MapLowLevelError(SSL_ERROR_SHA_DIGEST_FAILURE);
+            goto loser;
+        }
+
+        PRINT_BUF(10, (NULL, "Handshake hash computed over saved messages",
+                       ss->ssl3.hs.messages.buf,
+                       ss->ssl3.hs.messages.len));
+
+        if (PK11_DigestOp(ctx,
+                          ss->ssl3.hs.messages.buf,
+                          ss->ssl3.hs.messages.len) != SECSuccess) {
+            ssl_MapLowLevelError(SSL_ERROR_SHA_DIGEST_FAILURE);
+            goto loser;
+        }
+    } else {
+        ctx = PK11_CloneContext(ss->ssl3.hs.sha);
+        if (!ctx) {
+            ssl_MapLowLevelError(SSL_ERROR_SHA_DIGEST_FAILURE);
+            return SECFailure;
+        }
+    }
+
+    rv = PK11_DigestFinal(ctx, hashes->u.raw,
+                          &hashes->len,
+                          sizeof(hashes->u.raw));
+    if (rv != SECSuccess) {
+        ssl_MapLowLevelError(SSL_ERROR_DIGEST_FAILURE);
+        goto loser;
+    }
+    PORT_Assert(hashes->len == tls13_GetHashSize(ss));
+    PK11_DestroyContext(ctx, PR_TRUE);
+
+    return SECSuccess;
+
+loser:
+    PK11_DestroyContext(ctx, PR_TRUE);
+    return SECFailure;
+}
+
+void
+tls13_DestroyKeyShareEntry(TLS13KeyShareEntry *offer)
+{
+    SECITEM_ZfreeItem(&offer->key_exchange, PR_FALSE);
+    PORT_ZFree(offer, sizeof(*offer));
+}
+
+void
+tls13_DestroyKeyShares(PRCList *list)
+{
+    PRCList *cur_p;
+
+    /* The list must be initialized. */
+    PORT_Assert(PR_LIST_HEAD(list));
+
+    while (!PR_CLIST_IS_EMPTY(list)) {
+        cur_p = PR_LIST_TAIL(list);
+        PR_REMOVE_LINK(cur_p);
+        tls13_DestroyKeyShareEntry((TLS13KeyShareEntry *)cur_p);
+    }
+}
+
+void
+tls13_DestroyEarlyData(PRCList *list)
+{
+    PRCList *cur_p;
+
+    while (!PR_CLIST_IS_EMPTY(list)) {
+        TLS13EarlyData *msg;
+
+        cur_p = PR_LIST_TAIL(list);
+        msg = (TLS13EarlyData *)cur_p;
+
+        PR_REMOVE_LINK(cur_p);
+        SECITEM_ZfreeItem(&msg->data, PR_FALSE);
+        PORT_ZFree(msg, sizeof(*msg));
+    }
+}
+
+void
+tls13_DestroyCipherSpecs(PRCList *list)
+{
+    PRCList *cur_p;
+
+    while (!PR_CLIST_IS_EMPTY(list)) {
+        cur_p = PR_LIST_TAIL(list);
+        PR_REMOVE_LINK(cur_p);
+        ssl3_DestroyCipherSpec((ssl3CipherSpec *)cur_p, PR_FALSE);
+        PORT_Free(cur_p);
+    }
+}
+
+/* draft-ietf-tls-tls13 Section 5.2.2 specifies the following
+ * nonce algorithm:
+ *
+ * The length of the per-record nonce (iv_length) is set to max(8 bytes,
+ * N_MIN) for the AEAD algorithm (see [RFC5116] Section 4).  An AEAD
+ * algorithm where N_MAX is less than 8 bytes MUST NOT be used with TLS.
+ * The per-record nonce for the AEAD construction is formed as follows:
+ *
+ * 1.  The 64-bit record sequence number is padded to the left with
+ *     zeroes to iv_length.
+ *
+ * 2.  The padded sequence number is XORed with the static
+ *     client_write_iv or server_write_iv, depending on the role.
+ *
+ * The resulting quantity (of length iv_length) is used as the per-
+ * record nonce.
+ *
+ * Existing suites have the same nonce size: N_MIN = N_MAX = 12 bytes
+ *
+ * See RFC 5288 and https://tools.ietf.org/html/draft-ietf-tls-chacha20-poly1305-04#section-2
+ */
+static void
+tls13_WriteNonce(ssl3KeyMaterial *keys,
+                 const unsigned char *seqNumBuf, unsigned int seqNumLen,
+                 unsigned char *nonce, unsigned int nonceLen)
+{
+    size_t i;
+
+    PORT_Assert(nonceLen == 12);
+    memcpy(nonce, keys->write_iv, 12);
+
+    /* XOR the last 8 bytes of the IV with the sequence number. */
+    PORT_Assert(seqNumLen == 8);
+    for (i = 0; i < 8; ++i) {
+        nonce[4 + i] ^= seqNumBuf[i];
+    }
+}
+
+/* Implement the SSLAEADCipher interface defined in sslimpl.h.
+ *
+ * That interface takes the additional data (see below) and reinterprets that as
+ * a sequence number. In TLS 1.3 there is no additional data so this value is
+ * just the encoded sequence number.
+ */
+static SECStatus
+tls13_AEAD(ssl3KeyMaterial *keys, PRBool doDecrypt,
+           unsigned char *out, int *outlen, int maxout,
+           const unsigned char *in, int inlen,
+           CK_MECHANISM_TYPE mechanism,
+           unsigned char *aeadParams, unsigned int aeadParamLength)
+{
+    SECStatus rv;
+    unsigned int uOutLen = 0;
+    SECItem param = {
+        siBuffer, aeadParams, aeadParamLength
+    };
+
+    if (doDecrypt) {
+        rv = PK11_Decrypt(keys->write_key, mechanism, &param,
+                          out, &uOutLen, maxout, in, inlen);
+    } else {
+        rv = PK11_Encrypt(keys->write_key, mechanism, &param,
+                          out, &uOutLen, maxout, in, inlen);
+    }
+    *outlen = (int)uOutLen;
+
+    return rv;
+}
+
+static SECStatus
+tls13_AESGCM(ssl3KeyMaterial *keys,
+             PRBool doDecrypt,
+             unsigned char *out,
+             int *outlen,
+             int maxout,
+             const unsigned char *in,
+             int inlen,
+             const unsigned char *additionalData,
+             int additionalDataLen)
+{
+    CK_GCM_PARAMS gcmParams;
+    unsigned char nonce[12];
+
+    memset(&gcmParams, 0, sizeof(gcmParams));
+    gcmParams.pIv = nonce;
+    gcmParams.ulIvLen = sizeof(nonce);
+    gcmParams.pAAD = NULL;
+    gcmParams.ulAADLen = 0;
+    gcmParams.ulTagBits = 128; /* GCM measures tag length in bits. */
+
+    tls13_WriteNonce(keys, additionalData, additionalDataLen,
+                     nonce, sizeof(nonce));
+    return tls13_AEAD(keys, doDecrypt, out, outlen, maxout, in, inlen,
+                      CKM_AES_GCM,
+                      (unsigned char *)&gcmParams, sizeof(gcmParams));
+}
+
+static SECStatus
+tls13_ChaCha20Poly1305(ssl3KeyMaterial *keys, PRBool doDecrypt,
+                       unsigned char *out, int *outlen, int maxout,
+                       const unsigned char *in, int inlen,
+                       const unsigned char *additionalData,
+                       int additionalDataLen)
+{
+    CK_NSS_AEAD_PARAMS aeadParams;
+    unsigned char nonce[12];
+
+    memset(&aeadParams, 0, sizeof(aeadParams));
+    aeadParams.pNonce = nonce;
+    aeadParams.ulNonceLen = sizeof(nonce);
+    aeadParams.pAAD = NULL; /* No AAD in TLS 1.3. */
+    aeadParams.ulAADLen = 0;
+    aeadParams.ulTagLen = 16; /* The Poly1305 tag is 16 octets. */
+
+    tls13_WriteNonce(keys, additionalData, additionalDataLen,
+                     nonce, sizeof(nonce));
+    return tls13_AEAD(keys, doDecrypt, out, outlen, maxout, in, inlen,
+                      CKM_NSS_CHACHA20_POLY1305,
+                      (unsigned char *)&aeadParams, sizeof(aeadParams));
+}
+
+static SECStatus
+tls13_HandleEncryptedExtensions(sslSocket *ss, SSL3Opaque *b, PRUint32 length)
+{
+    SECStatus rv;
+    PRInt32 innerLength;
+    SECItem oldNpn = { siBuffer, NULL, 0 };
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+
+    SSL_TRC(3, ("%d: TLS13[%d]: handle encrypted extensions",
+                SSL_GETPID(), ss->fd));
+
+    rv = TLS13_CHECK_HS_STATE(ss, SSL_ERROR_RX_UNEXPECTED_ENCRYPTED_EXTENSIONS,
+                              wait_encrypted_extensions);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+
+    innerLength = ssl3_ConsumeHandshakeNumber(ss, 2, &b, &length);
+    if (innerLength < 0) {
+        return SECFailure; /* Alert already sent. */
+    }
+    if (innerLength != length) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_ENCRYPTED_EXTENSIONS,
+                    illegal_parameter);
+        return SECFailure;
+    }
+
+    /* If we are doing 0-RTT, then we already have an NPN value. Stash
+     * it for comparison. */
+    if (ss->ssl3.hs.zeroRttState == ssl_0rtt_sent &&
+        ss->xtnData.nextProtoState == SSL_NEXT_PROTO_EARLY_VALUE) {
+        oldNpn = ss->xtnData.nextProto;
+        ss->xtnData.nextProto.data = NULL;
+        ss->xtnData.nextProtoState = SSL_NEXT_PROTO_NO_SUPPORT;
+    }
+    rv = ssl3_HandleExtensions(ss, &b, &length, encrypted_extensions);
+    if (rv != SECSuccess) {
+        return SECFailure; /* Error code set below */
+    }
+
+    /* We can only get here if we offered 0-RTT. */
+    if (ssl3_ExtensionNegotiated(ss, ssl_tls13_early_data_xtn)) {
+        PORT_Assert(ss->ssl3.hs.zeroRttState == ssl_0rtt_sent);
+        if (!ss->statelessResume) {
+            /* Illegal to accept 0-RTT without also accepting PSK. */
+            FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_ENCRYPTED_EXTENSIONS,
+                        illegal_parameter);
+        }
+        ss->ssl3.hs.zeroRttState = ssl_0rtt_accepted;
+
+        /* Check that the server negotiated the same ALPN (if any). */
+        if (SECITEM_CompareItem(&oldNpn, &ss->xtnData.nextProto)) {
+            SECITEM_FreeItem(&oldNpn, PR_FALSE);
+            FATAL_ERROR(ss, SSL_ERROR_NEXT_PROTOCOL_DATA_INVALID,
+                        illegal_parameter);
+            return SECFailure;
+        }
+        /* Check that the server negotiated the same cipher suite. */
+        if (ss->ssl3.hs.cipher_suite != ss->ssl3.hs.zeroRttSuite) {
+            FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_ENCRYPTED_EXTENSIONS,
+                        illegal_parameter);
+            return SECFailure;
+        }
+    } else if (ss->ssl3.hs.zeroRttState == ssl_0rtt_sent) {
+        /* Though we sent 0-RTT, the early_data extension wasn't present so the
+         * state is unmodified; the server must have rejected 0-RTT. */
+        ss->ssl3.hs.zeroRttState = ssl_0rtt_ignored;
+        ss->ssl3.hs.zeroRttIgnore = ssl_0rtt_ignore_trial;
+    } else {
+        PORT_Assert(ss->ssl3.hs.zeroRttState == ssl_0rtt_none ||
+                    (ss->ssl3.hs.helloRetry &&
+                     ss->ssl3.hs.zeroRttState == ssl_0rtt_ignored));
+    }
+
+    SECITEM_FreeItem(&oldNpn, PR_FALSE);
+    if (ss->ssl3.hs.kea_def->authKeyType == ssl_auth_psk) {
+        TLS13_SET_HS_STATE(ss, wait_finished);
+    } else {
+        TLS13_SET_HS_STATE(ss, wait_cert_request);
+    }
+
+    return SECSuccess;
+}
+
+static SECStatus
+tls13_SendEncryptedExtensions(sslSocket *ss)
+{
+    SECStatus rv;
+    PRInt32 extensions_len = 0;
+    PRInt32 sent_len = 0;
+    PRUint32 maxBytes = 65535;
+
+    SSL_TRC(3, ("%d: TLS13[%d]: send encrypted extensions handshake",
+                SSL_GETPID(), ss->fd));
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveXmitBufLock(ss));
+
+    extensions_len = ssl3_CallHelloExtensionSenders(
+        ss, PR_FALSE, maxBytes, &ss->xtnData.encryptedExtensionsSenders[0]);
+
+    rv = ssl3_AppendHandshakeHeader(ss, encrypted_extensions,
+                                    extensions_len + 2);
+    if (rv != SECSuccess) {
+        LOG_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE);
+        return SECFailure;
+    }
+    rv = ssl3_AppendHandshakeNumber(ss, extensions_len, 2);
+    if (rv != SECSuccess) {
+        LOG_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE);
+        return SECFailure;
+    }
+    sent_len = ssl3_CallHelloExtensionSenders(
+        ss, PR_TRUE, extensions_len,
+        &ss->xtnData.encryptedExtensionsSenders[0]);
+    PORT_Assert(sent_len == extensions_len);
+    if (sent_len != extensions_len) {
+        LOG_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE);
+        PORT_Assert(sent_len == 0);
+        return SECFailure;
+    }
+
+    return SECSuccess;
+}
+
+SECStatus
+tls13_SendCertificateVerify(sslSocket *ss, SECKEYPrivateKey *privKey)
+{
+    SECStatus rv = SECFailure;
+    SECItem buf = { siBuffer, NULL, 0 };
+    unsigned int len;
+    SSLHashType hashAlg;
+    SSL3Hashes hash;
+    SSL3Hashes tbsHash; /* The hash "to be signed". */
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveXmitBufLock(ss));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+
+    SSL_TRC(3, ("%d: TLS13[%d]: send certificate_verify handshake",
+                SSL_GETPID(), ss->fd));
+
+    PORT_Assert(ss->ssl3.hs.hashType == handshake_hash_single);
+    rv = tls13_ComputeHandshakeHashes(ss, &hash);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+
+    /* We should have picked a signature scheme when we received a
+     * CertificateRequest, or when we picked a server certificate. */
+    PORT_Assert(ss->ssl3.hs.signatureScheme != ssl_sig_none);
+    if (ss->ssl3.hs.signatureScheme == ssl_sig_none) {
+        PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
+        return SECFailure;
+    }
+    hashAlg = ssl_SignatureSchemeToHashType(ss->ssl3.hs.signatureScheme);
+    rv = tls13_AddContextToHashes(ss, &hash, hashAlg,
+                                  PR_TRUE, &tbsHash);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+
+    rv = ssl3_SignHashes(ss, &tbsHash, privKey, &buf);
+    if (rv == SECSuccess && !ss->sec.isServer) {
+        /* Remember the info about the slot that did the signing.
+         * Later, when doing an SSL restart handshake, verify this.
+         * These calls are mere accessors, and can't fail.
+         */
+        PK11SlotInfo *slot;
+        sslSessionID *sid = ss->sec.ci.sid;
+
+        slot = PK11_GetSlotFromPrivateKey(privKey);
+        sid->u.ssl3.clAuthSeries = PK11_GetSlotSeries(slot);
+        sid->u.ssl3.clAuthSlotID = PK11_GetSlotID(slot);
+        sid->u.ssl3.clAuthModuleID = PK11_GetModuleID(slot);
+        sid->u.ssl3.clAuthValid = PR_TRUE;
+        PK11_FreeSlot(slot);
+    }
+    if (rv != SECSuccess) {
+        goto done; /* err code was set by ssl3_SignHashes */
+    }
+
+    len = buf.len + 2 + 2;
+
+    rv = ssl3_AppendHandshakeHeader(ss, certificate_verify, len);
+    if (rv != SECSuccess) {
+        goto done; /* error code set by AppendHandshake */
+    }
+
+    rv = ssl3_AppendHandshakeNumber(ss, ss->ssl3.hs.signatureScheme, 2);
+    if (rv != SECSuccess) {
+        goto done; /* err set by AppendHandshakeNumber */
+    }
+
+    rv = ssl3_AppendHandshakeVariable(ss, buf.data, buf.len, 2);
+    if (rv != SECSuccess) {
+        goto done; /* error code set by AppendHandshake */
+    }
+
+done:
+    /* For parity with the allocation functions, which don't use
+     * SECITEM_AllocItem(). */
+    if (buf.data)
+        PORT_Free(buf.data);
+    return rv;
+}
+
+/* Called from tls13_CompleteHandleHandshakeMessage() when it has deciphered a complete
+ * tls13 CertificateVerify message
+ * Caller must hold Handshake and RecvBuf locks.
+ */
+SECStatus
+tls13_HandleCertificateVerify(sslSocket *ss, SSL3Opaque *b, PRUint32 length,
+                              SSL3Hashes *hashes)
+{
+    SECItem signed_hash = { siBuffer, NULL, 0 };
+    SECStatus rv;
+    SSLSignatureScheme sigScheme;
+    SSLHashType hashAlg;
+    SSL3Hashes tbsHash;
+
+    SSL_TRC(3, ("%d: TLS13[%d]: handle certificate_verify handshake",
+                SSL_GETPID(), ss->fd));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+
+    rv = TLS13_CHECK_HS_STATE(ss, SSL_ERROR_RX_UNEXPECTED_CERT_VERIFY,
+                              wait_cert_verify);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+    PORT_Assert(hashes);
+
+    rv = ssl_ConsumeSignatureScheme(ss, &b, &length, &sigScheme);
+    if (rv != SECSuccess) {
+        PORT_SetError(SSL_ERROR_RX_MALFORMED_CERT_VERIFY);
+        return SECFailure;
+    }
+
+    rv = ssl_CheckSignatureSchemeConsistency(ss, sigScheme, ss->sec.peerCert);
+    if (rv != SECSuccess) {
+        /* Error set already */
+        return SECFailure;
+    }
+    hashAlg = ssl_SignatureSchemeToHashType(sigScheme);
+
+    rv = tls13_AddContextToHashes(ss, hashes, hashAlg, PR_FALSE, &tbsHash);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SSL_ERROR_DIGEST_FAILURE, internal_error);
+        return SECFailure;
+    }
+
+    rv = ssl3_ConsumeHandshakeVariable(ss, &signed_hash, 2, &b, &length);
+    if (rv != SECSuccess) {
+        PORT_SetError(SSL_ERROR_RX_MALFORMED_CERT_VERIFY);
+        return SECFailure;
+    }
+
+    if (length != 0) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_CERT_VERIFY, decode_error);
+        return SECFailure;
+    }
+
+    rv = ssl3_VerifySignedHashes(ss, sigScheme, &tbsHash, &signed_hash);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, PORT_GetError(), decrypt_error);
+        return SECFailure;
+    }
+
+    /* Set the auth type. */
+    if (!ss->sec.isServer) {
+        switch (ssl_SignatureSchemeToKeyType(sigScheme)) {
+            case rsaKey:
+                ss->sec.authType = ssl_auth_rsa_sign;
+                break;
+            case ecKey:
+                ss->sec.authType = ssl_auth_ecdsa;
+                break;
+            default:
+                PORT_Assert(PR_FALSE);
+        }
+    }
+
+    /* Request a client certificate now if one was requested. */
+    if (ss->ssl3.hs.certificateRequest) {
+        TLS13CertificateRequest *req = ss->ssl3.hs.certificateRequest;
+
+        PORT_Assert(!ss->sec.isServer);
+        rv = ssl3_CompleteHandleCertificateRequest(ss, req->signatureSchemes,
+                                                   req->signatureSchemeCount,
+                                                   &req->ca_list);
+        if (rv != SECSuccess) {
+            FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+            return rv;
+        }
+    }
+
+    TLS13_SET_HS_STATE(ss, wait_finished);
+
+    return SECSuccess;
+}
+
+static SECStatus
+tls13_ComputePskBinderHash(sslSocket *ss, unsigned long prefixLength,
+                           SSL3Hashes *hashes)
+{
+    SECStatus rv;
+
+    PORT_Assert(ss->ssl3.hs.hashType == handshake_hash_unknown);
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+    PORT_Assert(prefixLength <= ss->ssl3.hs.messages.len);
+
+    PRINT_BUF(10, (NULL, "Handshake hash computed over ClientHello prefix",
+                   ss->ssl3.hs.messages.buf, prefixLength));
+    rv = PK11_HashBuf(ssl3_HashTypeToOID(tls13_GetHash(ss)),
+                      hashes->u.raw,
+                      ss->ssl3.hs.messages.buf, prefixLength);
+    if (rv != SECSuccess) {
+        ssl_MapLowLevelError(SSL_ERROR_SHA_DIGEST_FAILURE);
+        goto loser;
+    }
+    hashes->len = tls13_GetHashSize(ss);
+
+    PRINT_BUF(10, (NULL, "PSK Binder hash",
+                   hashes->u.raw, hashes->len));
+
+    return SECSuccess;
+
+loser:
+    return SECFailure;
+}
+/* Compute the PSK Binder This is kind of sneaky.*/
+SECStatus
+tls13_ComputePskBinder(sslSocket *ss, PRBool sending,
+                       unsigned int prefixLength,
+                       PRUint8 *output, unsigned int *outputLen,
+                       unsigned int maxOutputLen)
+{
+    SSL3Hashes hashes;
+    SECStatus rv;
+
+    rv = tls13_ComputePskBinderHash(ss, prefixLength, &hashes);
+    if (rv != SECSuccess)
+        return SECFailure;
+
+    return tls13_ComputeFinished(ss, ss->ssl3.hs.pskBinderKey, &hashes,
+                                 sending, output, outputLen, maxOutputLen);
+}
+
+static SECStatus
+tls13_ComputeFinished(sslSocket *ss, PK11SymKey *baseKey,
+                      const SSL3Hashes *hashes,
+                      PRBool sending, PRUint8 *output, unsigned int *outputLen,
+                      unsigned int maxOutputLen)
+{
+    SECStatus rv;
+    PK11Context *hmacCtx = NULL;
+    CK_MECHANISM_TYPE macAlg = tls13_GetHmacMechanism(ss);
+    SECItem param = { siBuffer, NULL, 0 };
+    unsigned int outputLenUint;
+    const char *label = kHkdfLabelFinishedSecret;
+    PK11SymKey *secret = NULL;
+
+    PORT_Assert(baseKey);
+    SSL_TRC(3, ("%d: TLS13[%d]: %s calculate finished",
+                SSL_GETPID(), ss->fd, SSL_ROLE(ss)));
+    PRINT_BUF(50, (ss, "Handshake hash", hashes->u.raw, hashes->len));
+
+    /* Now derive the appropriate finished secret from the base secret. */
+    rv = tls13_HkdfExpandLabel(baseKey,
+                               tls13_GetHash(ss),
+                               NULL, 0,
+                               label, strlen(label),
+                               tls13_GetHmacMechanism(ss),
+                               tls13_GetHashSize(ss), &secret);
+    if (rv != SECSuccess) {
+        goto abort;
+    }
+
+    PORT_Assert(hashes->len == tls13_GetHashSize(ss));
+    hmacCtx = PK11_CreateContextBySymKey(macAlg, CKA_SIGN,
+                                         secret, &param);
+    if (!hmacCtx) {
+        goto abort;
+    }
+
+    rv = PK11_DigestBegin(hmacCtx);
+    if (rv != SECSuccess)
+        goto abort;
+
+    rv = PK11_DigestOp(hmacCtx, hashes->u.raw, hashes->len);
+    if (rv != SECSuccess)
+        goto abort;
+
+    PORT_Assert(maxOutputLen >= tls13_GetHashSize(ss));
+    rv = PK11_DigestFinal(hmacCtx, output, &outputLenUint, maxOutputLen);
+    if (rv != SECSuccess)
+        goto abort;
+    *outputLen = outputLenUint;
+
+    PK11_FreeSymKey(secret);
+    PK11_DestroyContext(hmacCtx, PR_TRUE);
+    return SECSuccess;
+
+abort:
+    if (secret) {
+        PK11_FreeSymKey(secret);
+    }
+
+    if (hmacCtx) {
+        PK11_DestroyContext(hmacCtx, PR_TRUE);
+    }
+
+    PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
+    return SECFailure;
+}
+
+static SECStatus
+tls13_SendFinished(sslSocket *ss, PK11SymKey *baseKey)
+{
+    SECStatus rv;
+    PRUint8 finishedBuf[TLS13_MAX_FINISHED_SIZE];
+    unsigned int finishedLen;
+    SSL3Hashes hashes;
+
+    SSL_TRC(3, ("%d: TLS13[%d]: send finished handshake", SSL_GETPID(), ss->fd));
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveXmitBufLock(ss));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+
+    rv = tls13_ComputeHandshakeHashes(ss, &hashes);
+    if (rv != SECSuccess) {
+        LOG_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE);
+        return SECFailure;
+    }
+
+    ssl_GetSpecReadLock(ss);
+    rv = tls13_ComputeFinished(ss, baseKey, &hashes, PR_TRUE,
+                               finishedBuf, &finishedLen, sizeof(finishedBuf));
+    ssl_ReleaseSpecReadLock(ss);
+    if (rv != SECSuccess) {
+        LOG_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE);
+        return SECFailure;
+    }
+
+    rv = ssl3_AppendHandshakeHeader(ss, finished, finishedLen);
+    if (rv != SECSuccess) {
+        return SECFailure; /* Error code already set. */
+    }
+
+    rv = ssl3_AppendHandshake(ss, finishedBuf, finishedLen);
+    if (rv != SECSuccess) {
+        return SECFailure; /* Error code already set. */
+    }
+
+    /* TODO(ekr@rtfm.com): Record key log */
+    return SECSuccess;
+}
+
+static SECStatus
+tls13_VerifyFinished(sslSocket *ss, SSL3HandshakeType message,
+                     PK11SymKey *secret,
+                     SSL3Opaque *b, PRUint32 length,
+                     const SSL3Hashes *hashes)
+{
+    SECStatus rv;
+    PRUint8 finishedBuf[TLS13_MAX_FINISHED_SIZE];
+    unsigned int finishedLen;
+
+    if (!hashes) {
+        FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+        return SECFailure;
+    }
+
+    rv = tls13_ComputeFinished(ss, secret, hashes, PR_FALSE,
+                               finishedBuf, &finishedLen, sizeof(finishedBuf));
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+        return SECFailure;
+    }
+
+    if (length != finishedLen) {
+#ifndef UNSAFE_FUZZER_MODE
+        FATAL_ERROR(ss, message == finished ? SSL_ERROR_RX_MALFORMED_FINISHED : SSL_ERROR_RX_MALFORMED_CLIENT_HELLO, illegal_parameter);
+        return SECFailure;
+#endif
+    }
+
+    if (NSS_SecureMemcmp(b, finishedBuf, finishedLen) != 0) {
+#ifndef UNSAFE_FUZZER_MODE
+        FATAL_ERROR(ss, SSL_ERROR_BAD_HANDSHAKE_HASH_VALUE,
+                    decrypt_error);
+        return SECFailure;
+#endif
+    }
+
+    return SECSuccess;
+}
+
+static SECStatus
+tls13_ClientHandleFinished(sslSocket *ss, SSL3Opaque *b, PRUint32 length,
+                           const SSL3Hashes *hashes)
+{
+    SECStatus rv;
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+
+    SSL_TRC(3, ("%d: TLS13[%d]: client handle finished handshake",
+                SSL_GETPID(), ss->fd));
+
+    rv = TLS13_CHECK_HS_STATE(ss, SSL_ERROR_RX_UNEXPECTED_FINISHED,
+                              wait_finished);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+
+    rv = tls13_VerifyFinished(ss, finished,
+                              ss->ssl3.hs.serverHsTrafficSecret,
+                              b, length, hashes);
+    if (rv != SECSuccess)
+        return SECFailure;
+
+    return tls13_SendClientSecondRound(ss);
+}
+
+static SECStatus
+tls13_ServerHandleFinished(sslSocket *ss, SSL3Opaque *b, PRUint32 length,
+                           const SSL3Hashes *hashes)
+{
+    SECStatus rv;
+    PK11SymKey *secret;
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+
+    SSL_TRC(3, ("%d: TLS13[%d]: server handle finished handshake",
+                SSL_GETPID(), ss->fd));
+
+    rv = TLS13_CHECK_HS_STATE(ss, SSL_ERROR_RX_UNEXPECTED_FINISHED, wait_finished);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+
+    if (TLS13_IN_HS_STATE(ss, wait_finished)) {
+        secret = ss->ssl3.hs.clientHsTrafficSecret;
+    } else {
+        secret = ss->ssl3.hs.clientEarlyTrafficSecret;
+    }
+
+    rv = tls13_VerifyFinished(ss, finished, secret, b, length, hashes);
+    if (rv != SECSuccess)
+        return SECFailure;
+
+    rv = tls13_SetCipherSpec(ss, TrafficKeyApplicationData,
+                             CipherSpecRead, PR_TRUE);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+        return SECFailure;
+    }
+
+    rv = tls13_FinishHandshake(ss);
+    if (rv != SECSuccess) {
+        return SECFailure; /* Error code and alerts handled below */
+    }
+    ssl_GetXmitBufLock(ss);
+    if (ss->opt.enableSessionTickets) {
+        rv = tls13_SendNewSessionTicket(ss);
+        if (rv != SECSuccess) {
+            ssl_ReleaseXmitBufLock(ss);
+            return SECFailure; /* Error code and alerts handled below */
+        }
+        rv = ssl3_FlushHandshake(ss, 0);
+    }
+    ssl_ReleaseXmitBufLock(ss);
+    if (rv != SECSuccess)
+        return SECFailure;
+
+    return SECSuccess;
+}
+
+static SECStatus
+tls13_FinishHandshake(sslSocket *ss)
+{
+    SECStatus rv;
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+    PORT_Assert(ss->ssl3.hs.restartTarget == NULL);
+
+    rv = tls13_ComputeFinalSecrets(ss);
+    if (rv != SECSuccess)
+        return SECFailure;
+
+    /* The first handshake is now completed. */
+    ss->handshake = NULL;
+
+    /* Don't need this. */
+    PK11_FreeSymKey(ss->ssl3.hs.clientHsTrafficSecret);
+    ss->ssl3.hs.clientHsTrafficSecret = NULL;
+    PK11_FreeSymKey(ss->ssl3.hs.serverHsTrafficSecret);
+    ss->ssl3.hs.serverHsTrafficSecret = NULL;
+
+    TLS13_SET_HS_STATE(ss, idle_handshake);
+
+    ssl_FinishHandshake(ss);
+
+    return SECSuccess;
+}
+
+/* Do the parts of sending the client's second round that require
+ * the XmitBuf lock. */
+static SECStatus
+tls13_SendClientSecondFlight(sslSocket *ss, PRBool sendClientCert,
+                             SSL3AlertDescription *sendAlert)
+{
+    SECStatus rv;
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveXmitBufLock(ss));
+
+    *sendAlert = internal_error;
+
+    if (ss->ssl3.sendEmptyCert) {
+        ss->ssl3.sendEmptyCert = PR_FALSE;
+        rv = ssl3_SendEmptyCertificate(ss);
+        /* Don't send verify */
+        if (rv != SECSuccess) {
+            return SECFailure; /* error code is set. */
+        }
+    } else if (sendClientCert) {
+        rv = tls13_SendCertificate(ss);
+        if (rv != SECSuccess) {
+            return SECFailure; /* error code is set. */
+        }
+    }
+    if (ss->ssl3.hs.certificateRequest) {
+        PORT_FreeArena(ss->ssl3.hs.certificateRequest->arena, PR_FALSE);
+        ss->ssl3.hs.certificateRequest = NULL;
+    }
+
+    if (sendClientCert) {
+        rv = tls13_SendCertificateVerify(ss, ss->ssl3.clientPrivateKey);
+        SECKEY_DestroyPrivateKey(ss->ssl3.clientPrivateKey);
+        ss->ssl3.clientPrivateKey = NULL;
+        if (rv != SECSuccess) {
+            return SECFailure; /* err is set. */
+        }
+    }
+
+    rv = tls13_SendFinished(ss, ss->ssl3.hs.clientHsTrafficSecret);
+    if (rv != SECSuccess) {
+        return SECFailure; /* err code was set. */
+    }
+    rv = ssl3_FlushHandshake(ss, IS_DTLS(ss) ? ssl_SEND_FLAG_NO_RETRANSMIT : 0);
+    if (rv != SECSuccess) {
+        /* No point in sending an alert here because we're not going to
+         * be able to send it if we couldn't flush the handshake. */
+        *sendAlert = no_alert;
+        return SECFailure;
+    }
+
+    rv = dtls_StartHolddownTimer(ss);
+    if (rv != SECSuccess) {
+        return SECFailure; /* err code was set. */
+    }
+
+    return SECSuccess;
+}
+
+static SECStatus
+tls13_SendClientSecondRound(sslSocket *ss)
+{
+    SECStatus rv;
+    PRBool sendClientCert;
+    SSL3AlertDescription sendAlert = no_alert;
+
+    PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
+    PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
+
+    sendClientCert = !ss->ssl3.sendEmptyCert &&
+                     ss->ssl3.clientCertChain != NULL &&
+                     ss->ssl3.clientPrivateKey != NULL;
+
+    /* Defer client authentication sending if we are still waiting for server
+     * authentication.  This avoids unnecessary disclosure of client credentials
+     * to an unauthenticated server.
+     */
+    if (ss->ssl3.hs.restartTarget) {
+        PR_NOT_REACHED("unexpected ss->ssl3.hs.restartTarget");
+        PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
+        return SECFailure;
+    }
+    if (ss->ssl3.hs.authCertificatePending) {
+        SSL_TRC(3, ("%d: TLS13[%d]: deferring ssl3_SendClientSecondRound because"
+                    " certificate authentication is still pending.",
+                    SSL_GETPID(), ss->fd));
+        ss->ssl3.hs.restartTarget = tls13_SendClientSecondRound;
+        return SECWouldBlock;
+    }
+
+    if (ss->ssl3.hs.zeroRttState != ssl_0rtt_none) {
+        if (ss->ssl3.hs.zeroRttState == ssl_0rtt_accepted) {
+            rv = tls13_SendEndOfEarlyData(ss);
+            if (rv != SECSuccess) {
+                return SECFailure; /* Error code already set. */
+            }
+        }
+        if (IS_DTLS(ss) && !ss->ssl3.hs.helloRetry) {
+            /* Reset the counters so that the next epoch isn't set
+             * incorrectly. */
+            tls13_SetNullCipherSpec(ss, &ss->ssl3.cwSpec);
+        }
+    }
+
+    rv = tls13_SetCipherSpec(ss, TrafficKeyHandshake,
+                             CipherSpecWrite, PR_FALSE);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SSL_ERROR_INIT_CIPHER_SUITE_FAILURE, internal_error);
+        return SECFailure;
+    }
+
+    rv = tls13_ComputeApplicationSecrets(ss);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+        return SECFailure;
+    }
+
+    rv = tls13_SetCipherSpec(ss, TrafficKeyApplicationData,
+                             CipherSpecRead, PR_FALSE);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+        return SECFailure;
+    }
+
+    ssl_GetXmitBufLock(ss); /*******************************/
+    rv = tls13_SendClientSecondFlight(ss, sendClientCert, &sendAlert);
+    ssl_ReleaseXmitBufLock(ss); /*******************************/
+    if (rv != SECSuccess) {
+        if (sendAlert != no_alert) {
+            FATAL_ERROR(ss, PORT_GetError(), sendAlert);
+        } else {
+            LOG_ERROR(ss, PORT_GetError());
+        }
+        return SECFailure;
+    }
+    rv = tls13_SetCipherSpec(ss, TrafficKeyApplicationData,
+                             CipherSpecWrite, PR_TRUE);
+    if (rv != SECSuccess) {
+        PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
+        return SECFailure;
+    }
+
+    /* The handshake is now finished */
+    return tls13_FinishHandshake(ss);
+}
+
+/*
+ *  enum { (65535) } TicketExtensionType;
+ *
+ *  struct {
+ *      TicketExtensionType extension_type;
+ *      opaque extension_data<0..2^16-1>;
+ *  } TicketExtension;
+ *
+ *   struct {
+ *       uint32 ticket_lifetime;
+ *       uint32 ticket_age_add;
+ *       opaque ticket<1..2^16-1>;
+ *       TicketExtension extensions<0..2^16-2>;
+ *   } NewSessionTicket;
+ */
+
+#define MAX_EARLY_DATA_SIZE (2 << 16) /* Arbitrary limit. */
+
+SECStatus
+tls13_SendNewSessionTicket(sslSocket *ss)
+{
+    PRUint16 message_length;
+    SECItem ticket_data = { 0, NULL, 0 };
+    SECStatus rv;
+    NewSessionTicket ticket = { 0 };
+    PRUint32 max_early_data_size_len = 0;
+    ticket.flags = 0;
+    if (ss->opt.enable0RttData) {
+        ticket.flags |= ticket_allow_early_data;
+        max_early_data_size_len = 8; /* type + len + value. */
+    }
+    ticket.ticket_lifetime_hint = TLS_EX_SESS_TICKET_LIFETIME_HINT;
+
+    rv = ssl3_EncodeSessionTicket(ss, &ticket, &ticket_data);
+    if (rv != SECSuccess)
+        goto loser;
+
+    message_length =
+        4 +                           /* lifetime */
+        4 +                           /* ticket_age_add */
+        2 + max_early_data_size_len + /* max_early_data_size_len */
+        2 +                           /* ticket length */
+        ticket_data.len;
+
+    rv = ssl3_AppendHandshakeHeader(ss, new_session_ticket,
+                                    message_length);
+    if (rv != SECSuccess)
+        goto loser;
+
+    /* This is a fixed value. */
+    rv = ssl3_AppendHandshakeNumber(ss, TLS_EX_SESS_TICKET_LIFETIME_HINT, 4);
+    if (rv != SECSuccess)
+        goto loser;
+
+    /* The ticket age obfuscator. */
+    rv = PK11_GenerateRandom((PRUint8 *)&ticket.ticket_age_add,
+                             sizeof(ticket.ticket_age_add));
+    if (rv != SECSuccess)
+        goto loser;
+
+    rv = ssl3_AppendHandshakeNumber(ss, ticket.ticket_age_add, 4);
+    if (rv != SECSuccess)
+        goto loser;
+
+    /* Encode the ticket. */
+    rv = ssl3_AppendHandshakeVariable(
+        ss, ticket_data.data, ticket_data.len, 2);
+    if (rv != SECSuccess)
+        goto loser;
+
+    /* Extensions. */
+    rv = ssl3_AppendHandshakeNumber(ss, max_early_data_size_len, 2);
+    if (rv != SECSuccess)
+        goto loser;
+
+    if (max_early_data_size_len) {
+        rv = ssl3_AppendHandshakeNumber(
+            ss, ssl_tls13_ticket_early_data_info_xtn, 2);
+        if (rv != SECSuccess)
+            goto loser;
+
+        /* Length */
+        rv = ssl3_AppendHandshakeNumber(ss, 4, 2);
+        if (rv != SECSuccess)
+            goto loser;
+
+        rv = ssl3_AppendHandshakeNumber(ss, MAX_EARLY_DATA_SIZE, 4);
+        if (rv != SECSuccess)
+            goto loser;
+    }
+
+    SECITEM_FreeItem(&ticket_data, PR_FALSE);
+    return SECSuccess;
+
+loser:
+    if (ticket_data.data) {
+        SECITEM_FreeItem(&ticket_data, PR_FALSE);
+    }
+    return SECFailure;
+}
+
+static SECStatus
+tls13_HandleNewSessionTicket(sslSocket *ss, SSL3Opaque *b, PRUint32 length)
+{
+    SECStatus rv;
+    PRInt32 tmp;
+    PRUint32 utmp;
+    NewSessionTicket ticket = { 0 };
+    SECItem data;
+    SECItem ticket_data;
+
+    SSL_TRC(3, ("%d: TLS13[%d]: handle new session ticket message",
+                SSL_GETPID(), ss->fd));
+
+    rv = TLS13_CHECK_HS_STATE(ss, SSL_ERROR_RX_UNEXPECTED_NEW_SESSION_TICKET,
+                              idle_handshake);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+    if (!ss->firstHsDone || ss->sec.isServer) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_UNEXPECTED_NEW_SESSION_TICKET,
+                    unexpected_message);
+        return SECFailure;
+    }
+
+    ticket.received_timestamp = ssl_Time();
+    tmp = ssl3_ConsumeHandshakeNumber(ss, 4, &b, &length);
+    if (tmp < 0) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_NEW_SESSION_TICKET,
+                    decode_error);
+        return SECFailure;
+    }
+    ticket.ticket_lifetime_hint = (PRUint32)tmp;
+    ticket.ticket.type = siBuffer;
+
+    rv = ssl3_ConsumeHandshake(ss, &utmp, sizeof(utmp),
+                               &b, &length);
+    if (rv != SECSuccess) {
+        PORT_SetError(SSL_ERROR_RX_MALFORMED_NEW_SESSION_TICKET);
+        return SECFailure;
+    }
+    ticket.ticket_age_add = PR_ntohl(utmp);
+
+    /* Get the ticket value. */
+    rv = ssl3_ConsumeHandshakeVariable(ss, &ticket_data, 2, &b, &length);
+    if (rv != SECSuccess || !ticket_data.len) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_NEW_SESSION_TICKET,
+                    decode_error);
+        return SECFailure;
+    }
+
+    /* Parse extensions. */
+    rv = ssl3_ConsumeHandshakeVariable(ss, &data, 2, &b, &length);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_NEW_SESSION_TICKET,
+                    decode_error);
+        return SECFailure;
+    }
+
+    rv = ssl3_HandleExtensions(ss, &data.data,
+                               &data.len, new_session_ticket);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_NEW_SESSION_TICKET,
+                    decode_error);
+        return SECFailure;
+    }
+    if (ss->xtnData.max_early_data_size) {
+        ticket.flags |= ticket_allow_early_data;
+        ticket.max_early_data_size = ss->xtnData.max_early_data_size;
+    }
+
+    if (length != 0) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_NEW_SESSION_TICKET,
+                    decode_error);
+        return SECFailure;
+    }
+
+    if (!ss->opt.noCache) {
+        PORT_Assert(ss->sec.ci.sid);
+        rv = SECITEM_CopyItem(NULL, &ticket.ticket, &ticket_data);
+        if (rv != SECSuccess) {
+            FATAL_ERROR(ss, SEC_ERROR_NO_MEMORY, internal_error);
+            return SECFailure;
+        }
+        PRINT_BUF(50, (ss, "Caching session ticket",
+                       ticket.ticket.data,
+                       ticket.ticket.len));
+
+        /* Replace a previous session ticket when
+         * we receive a second NewSessionTicket message. */
+        if (ss->sec.ci.sid->cached == in_client_cache) {
+            /* Create a new session ID. */
+            sslSessionID *sid = ssl3_NewSessionID(ss, PR_FALSE);
+            if (!sid) {
+                return SECFailure;
+            }
+
+            /* Copy over the peerCert. */
+            PORT_Assert(ss->sec.ci.sid->peerCert);
+            sid->peerCert = CERT_DupCertificate(ss->sec.ci.sid->peerCert);
+            if (!sid->peerCert) {
+                ssl_FreeSID(sid);
+                return SECFailure;
+            }
+
+            /* Destroy the old SID. */
+            ss->sec.uncache(ss->sec.ci.sid);
+            ssl_FreeSID(ss->sec.ci.sid);
+            ss->sec.ci.sid = sid;
+        }
+
+        ssl3_SetSIDSessionTicket(ss->sec.ci.sid, &ticket);
+        PORT_Assert(!ticket.ticket.data);
+
+        rv = ssl3_FillInCachedSID(ss, ss->sec.ci.sid);
+        if (rv != SECSuccess)
+            return SECFailure;
+
+        /* Cache the session. */
+        ss->sec.cache(ss->sec.ci.sid);
+    }
+
+    return SECSuccess;
+}
+
+typedef enum {
+    ExtensionNotUsed,
+    ExtensionClientOnly,
+    ExtensionSendClear,
+    ExtensionSendClearOrHrr,
+    ExtensionSendHrr,
+    ExtensionSendEncrypted,
+    ExtensionSendCertificate,
+    ExtensionNewSessionTicket
+} Tls13ExtensionStatus;
+
+static const struct {
+    PRUint16 ex_value;
+    Tls13ExtensionStatus status;
+} KnownExtensions[] = {
+    { ssl_server_name_xtn, ExtensionSendEncrypted },
+    { ssl_supported_groups_xtn, ExtensionSendEncrypted },
+    { ssl_ec_point_formats_xtn, ExtensionNotUsed },
+    { ssl_signature_algorithms_xtn, ExtensionClientOnly },
+    { ssl_use_srtp_xtn, ExtensionSendEncrypted },
+    { ssl_app_layer_protocol_xtn, ExtensionSendEncrypted },
+    { ssl_padding_xtn, ExtensionNotUsed },
+    { ssl_extended_master_secret_xtn, ExtensionNotUsed },
+    { ssl_session_ticket_xtn, ExtensionClientOnly },
+    { ssl_tls13_key_share_xtn, ExtensionSendClearOrHrr },
+    { ssl_tls13_pre_shared_key_xtn, ExtensionSendClear },
+    { ssl_tls13_early_data_xtn, ExtensionSendEncrypted },
+    { ssl_next_proto_nego_xtn, ExtensionNotUsed },
+    { ssl_renegotiation_info_xtn, ExtensionNotUsed },
+    { ssl_signed_cert_timestamp_xtn, ExtensionSendCertificate },
+    { ssl_cert_status_xtn, ExtensionSendCertificate },
+    { ssl_tls13_ticket_early_data_info_xtn, ExtensionNewSessionTicket },
+    { ssl_tls13_cookie_xtn, ExtensionSendHrr },
+    { ssl_tls13_short_header_xtn, ExtensionSendClear }
+};
+
+PRBool
+tls13_ExtensionAllowed(PRUint16 extension, SSL3HandshakeType message)
+{
+    unsigned int i;
+
+    PORT_Assert((message == client_hello) ||
+                (message == server_hello) ||
+                (message == hello_retry_request) ||
+                (message == encrypted_extensions) ||
+                (message == new_session_ticket) ||
+                (message == certificate));
+
+    for (i = 0; i < PR_ARRAY_SIZE(KnownExtensions); i++) {
+        if (KnownExtensions[i].ex_value == extension)
+            break;
+    }
+    if (i == PR_ARRAY_SIZE(KnownExtensions)) {
+        /* We have never heard of this extension which is OK
+         * in client_hello and new_session_ticket. */
+        return (message == client_hello) ||
+               (message == new_session_ticket);
+    }
+
+    switch (KnownExtensions[i].status) {
+        case ExtensionNotUsed:
+            return PR_FALSE;
+        case ExtensionClientOnly:
+            return message == client_hello;
+        case ExtensionSendClear:
+            return message == client_hello ||
+                   message == server_hello;
+        case ExtensionSendClearOrHrr:
+            return message == client_hello ||
+                   message == server_hello ||
+                   message == hello_retry_request;
+        case ExtensionSendHrr:
+            return message == client_hello ||
+                   message == hello_retry_request;
+        case ExtensionSendEncrypted:
+            return message == client_hello ||
+                   message == encrypted_extensions;
+        case ExtensionNewSessionTicket:
+            return message == new_session_ticket;
+        case ExtensionSendCertificate:
+            return message == client_hello ||
+                   message == certificate;
+    }
+
+    PORT_Assert(0);
+
+    /* Not reached */
+    return PR_TRUE;
+}
+
+/* TLS 1.3 doesn't actually have additional data but the aead function
+ * signature overloads additional data to carry the record sequence
+ * number and that's what we put here. The TLS 1.3 AEAD functions
+ * just use this input as the sequence number and not as additional
+ * data. */
+static void
+tls13_FormatAdditionalData(PRUint8 *aad, unsigned int length,
+                           sslSequenceNumber seqNum)
+{
+    PRUint8 *ptr = aad;
+
+    PORT_Assert(length == 8);
+    ptr = ssl_EncodeUintX(seqNum, 8, ptr);
+    PORT_Assert((ptr - aad) == length);
+}
+
+SECStatus
+tls13_ProtectRecord(sslSocket *ss,
+                    ssl3CipherSpec *cwSpec,
+                    SSL3ContentType type,
+                    const SSL3Opaque *pIn,
+                    PRUint32 contentLen,
+                    sslBuffer *wrBuf)
+{
+    const ssl3BulkCipherDef *cipher_def = cwSpec->cipher_def;
+    const int tagLen = cipher_def->tag_size;
+    SECStatus rv;
+
+    SSL_TRC(3, ("%d: TLS13[%d]: spec=%d (%s) protect record 0x%0llx len=%u",
+                SSL_GETPID(), ss->fd, cwSpec, cwSpec->phase,
+                cwSpec->write_seq_num, contentLen));
+
+    if (contentLen + 1 + tagLen > wrBuf->space) {
+        PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
+        return SECFailure;
+    }
+
+    /* Copy the data into the wrBuf. We're going to encrypt in-place
+     * in the AEAD branch anyway */
+    PORT_Memcpy(wrBuf->buf, pIn, contentLen);
+
+    if (cipher_def->calg == ssl_calg_null) {
+        /* Shortcut for plaintext */
+        wrBuf->len = contentLen;
+    } else {
+        PRUint8 aad[8];
+        PORT_Assert(cipher_def->type == type_aead);
+
+        /* Add the content type at the end. */
+        wrBuf->buf[contentLen] = type;
+
+        tls13_FormatAdditionalData(aad, sizeof(aad), cwSpec->write_seq_num);
+        rv = cwSpec->aead(
+            ss->sec.isServer ? &cwSpec->server : &cwSpec->client,
+            PR_FALSE,                   /* do encrypt */
+            wrBuf->buf,                 /* output  */
+            (int *)&wrBuf->len,         /* out len */
+            wrBuf->space,               /* max out */
+            wrBuf->buf, contentLen + 1, /* input   */
+            aad, sizeof(aad));
+        if (rv != SECSuccess) {
+            PORT_SetError(SSL_ERROR_ENCRYPTION_FAILURE);
+            return SECFailure;
+        }
+    }
+
+    return SECSuccess;
+}
+
+/* Unprotect a TLS 1.3 record and leave the result in plaintext.
+ *
+ * Called by ssl3_HandleRecord. Caller must hold the spec read lock.
+ * Therefore, we MUST not call SSL3_SendAlert().
+ *
+ * If SECFailure is returned, we:
+ * 1. Set |*alert| to the alert to be sent.
+ * 2. Call PORT_SetError() witn an appropriate code.
+ */
+SECStatus
+tls13_UnprotectRecord(sslSocket *ss, SSL3Ciphertext *cText, sslBuffer *plaintext,
+                      SSL3AlertDescription *alert)
+{
+    ssl3CipherSpec *crSpec = ss->ssl3.crSpec;
+    const ssl3BulkCipherDef *cipher_def = crSpec->cipher_def;
+    PRUint8 aad[8];
+    SECStatus rv;
+
+    *alert = bad_record_mac; /* Default alert for most issues. */
+
+    SSL_TRC(3, ("%d: TLS13[%d]: spec=%d (%s) unprotect record 0x%0llx len=%u",
+                SSL_GETPID(), ss->fd, crSpec, crSpec->phase,
+                crSpec->read_seq_num, cText->buf->len));
+
+    /* We can perform this test in variable time because the record's total
+     * length and the ciphersuite are both public knowledge. */
+    if (cText->buf->len < cipher_def->tag_size) {
+        SSL_TRC(3,
+                ("%d: TLS13[%d]: record too short to contain valid AEAD data",
+                 SSL_GETPID(), ss->fd));
+        PORT_SetError(SSL_ERROR_BAD_MAC_READ);
+        return SECFailure;
+    }
+
+    /* Verify that the content type is right, even though we overwrite it. */
+    if (cText->type != content_application_data) {
+        SSL_TRC(3,
+                ("%d: TLS13[%d]: record has invalid exterior content type=%d",
+                 SSL_GETPID(), ss->fd, cText->type));
+        /* Do we need a better error here? */
+        PORT_SetError(SSL_ERROR_BAD_MAC_READ);
+        return SECFailure;
+    }
+
+    /* Check the version number in the record */
+    if ((IS_DTLS(ss) && cText->version != kDtlsRecordVersion) ||
+        (!IS_DTLS(ss) && cText->version != kTlsRecordVersion)) {
+        /* Do we need a better error here? */
+        SSL_TRC(3,
+                ("%d: TLS13[%d]: record has bogus version",
+                 SSL_GETPID(), ss->fd));
+        return SECFailure;
+    }
+
+    /* Decrypt */
+    PORT_Assert(cipher_def->type == type_aead);
+    tls13_FormatAdditionalData(aad, sizeof(aad),
+                               IS_DTLS(ss) ? cText->seq_num
+                                           : crSpec->read_seq_num);
+    rv = crSpec->aead(
+        ss->sec.isServer ? &crSpec->client : &crSpec->server,
+        PR_TRUE,                /* do decrypt */
+        plaintext->buf,         /* out */
+        (int *)&plaintext->len, /* outlen */
+        plaintext->space,       /* maxout */
+        cText->buf->buf,        /* in */
+        cText->buf->len,        /* inlen */
+        aad, sizeof(aad));
+    if (rv != SECSuccess) {
+        SSL_TRC(3,
+                ("%d: TLS13[%d]: record has bogus MAC",
+                 SSL_GETPID(), ss->fd));
+        PORT_SetError(SSL_ERROR_BAD_MAC_READ);
+        return SECFailure;
+    }
+
+    /* The record is right-padded with 0s, followed by the true
+     * content type, so read from the right until we receive a
+     * nonzero byte. */
+    while (plaintext->len > 0 && !(plaintext->buf[plaintext->len - 1])) {
+        --plaintext->len;
+    }
+
+    /* Bogus padding. */
+    if (plaintext->len < 1) {
+        SSL_TRC(3,
+                ("%d: TLS13[%d]: empty record",
+                 SSL_GETPID(), ss->fd, cText->type));
+        /* It's safe to report this specifically because it happened
+         * after the MAC has been verified. */
+        PORT_SetError(SSL_ERROR_BAD_BLOCK_PADDING);
+        return SECFailure;
+    }
+
+    /* Record the type. */
+    cText->type = plaintext->buf[plaintext->len - 1];
+    --plaintext->len;
+
+    SSL_TRC(10,
+            ("%d: TLS13[%d]: %s received record of length=%d type=%d",
+             SSL_GETPID(), ss->fd, SSL_ROLE(ss),
+             plaintext->len, cText->type));
+
+    return SECSuccess;
+}
+
+/* 0-RTT is only permitted if:
+ *
+ * 1. We are doing TLS 1.3
+ * 2. This isn't a second ClientHello (in response to HelloRetryRequest)
+ * 3. The 0-RTT option is set.
+ * 4. We have a valid ticket.
+ * 5. The server is willing to accept 0-RTT.
+ * 6. We have not changed our ALPN settings to disallow the ALPN tag
+ *    in the ticket.
+ *
+ * Called from tls13_ClientSendEarlyDataXtn().
+ */
+PRBool
+tls13_ClientAllow0Rtt(const sslSocket *ss, const sslSessionID *sid)
+{
+    /* We checked that the cipher suite was still allowed back in
+     * ssl3_SendClientHello. */
+    if (sid->version < SSL_LIBRARY_VERSION_TLS_1_3)
+        return PR_FALSE;
+    if (ss->ssl3.hs.helloRetry)
+        return PR_FALSE;
+    if (!ss->opt.enable0RttData)
+        return PR_FALSE;
+    if (!ss->statelessResume)
+        return PR_FALSE;
+    if ((sid->u.ssl3.locked.sessionTicket.flags & ticket_allow_early_data) == 0)
+        return PR_FALSE;
+    return tls13_AlpnTagAllowed(ss, &sid->u.ssl3.alpnSelection);
+}
+
+SECStatus
+tls13_MaybeDo0RTTHandshake(sslSocket *ss)
+{
+    SECStatus rv;
+
+    /* Don't do anything if there is no early_data xtn, which means we're
+     * not doing early data. */
+    if (!ssl3_ClientExtensionAdvertised(ss, ssl_tls13_early_data_xtn)) {
+        return SECSuccess;
+    }
+
+    ss->ssl3.hs.zeroRttState = ssl_0rtt_sent;
+    ss->ssl3.hs.zeroRttSuite = ss->ssl3.hs.cipher_suite;
+
+    SSL_TRC(3, ("%d: TLS13[%d]: in 0-RTT mode", SSL_GETPID(), ss->fd));
+
+    /* Set the ALPN data as if it was negotiated. We check in the ServerHello
+     * handler that the server negotiates the same value. */
+    if (ss->sec.ci.sid->u.ssl3.alpnSelection.len) {
+        ss->xtnData.nextProtoState = SSL_NEXT_PROTO_EARLY_VALUE;
+        rv = SECITEM_CopyItem(NULL, &ss->xtnData.nextProto,
+                              &ss->sec.ci.sid->u.ssl3.alpnSelection);
+        if (rv != SECSuccess)
+            return rv;
+    }
+
+    /* Null spec... */
+    ssl_GetSpecReadLock(ss);
+    ss->ssl3.hs.nullSpec = ss->ssl3.cwSpec;
+    tls13_CipherSpecAddRef(ss->ssl3.hs.nullSpec);
+    ssl_ReleaseSpecReadLock(ss);
+
+    /* Cipher suite already set in tls13_SetupClientHello. */
+    ss->ssl3.hs.preliminaryInfo = 0; /* TODO(ekr@rtfm.com) Fill this in.
+                                      * bug 1281255. */
+
+    rv = tls13_DeriveSecret(ss, ss->ssl3.hs.currentSecret,
+                            kHkdfLabelClient,
+                            kHkdfLabelEarlyTrafficSecret,
+                            NULL,
+                            &ss->ssl3.hs.clientEarlyTrafficSecret);
+    if (rv != SECSuccess)
+        return SECFailure;
+
+    rv = tls13_SetCipherSpec(ss, TrafficKeyEarlyApplicationData,
+                             CipherSpecWrite, PR_TRUE);
+    if (rv != SECSuccess) {
+        return rv;
+    }
+
+    return SECSuccess;
+}
+
+PRInt32
+tls13_Read0RttData(sslSocket *ss, void *buf, PRInt32 len)
+{
+    TLS13EarlyData *msg;
+
+    PORT_Assert(!PR_CLIST_IS_EMPTY(&ss->ssl3.hs.bufferedEarlyData));
+    msg = (TLS13EarlyData *)PR_NEXT_LINK(&ss->ssl3.hs.bufferedEarlyData);
+
+    PR_REMOVE_LINK(&msg->link);
+    if (msg->data.len > len) {
+        PORT_SetError(SSL_ERROR_ILLEGAL_PARAMETER_ALERT);
+        return SECFailure;
+    }
+    len = msg->data.len;
+
+    PORT_Memcpy(buf, msg->data.data, msg->data.len);
+    SECITEM_ZfreeItem(&msg->data, PR_FALSE);
+    PORT_ZFree(msg, sizeof(*msg));
+
+    return len;
+}
+
+/* 0-RTT data will be followed by a different cipher spec; this resets the
+ * current spec to the null spec so that the following state can be set as
+ * though 0-RTT didn't happen. TODO: work out if this is the best plan. */
+static void
+tls13_SetNullCipherSpec(sslSocket *ss, ssl3CipherSpec **specp)
+{
+    PORT_Assert(ss->ssl3.hs.nullSpec);
+
+    ssl_GetSpecWriteLock(ss);
+    tls13_CipherSpecRelease(*specp);
+    *specp = ss->ssl3.hs.nullSpec;
+    ssl_ReleaseSpecWriteLock(ss);
+    ss->ssl3.hs.nullSpec = NULL;
+}
+
+static SECStatus
+tls13_SendEndOfEarlyData(sslSocket *ss)
+{
+    SECStatus rv;
+
+    SSL_TRC(3, ("%d: TLS13[%d]: send end_of_early_data extension",
+                SSL_GETPID(), ss->fd));
+
+    rv = SSL3_SendAlert(ss, alert_warning, end_of_early_data);
+    if (rv != SECSuccess) {
+        FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+        return SECFailure;
+    }
+
+    ss->ssl3.hs.zeroRttState = ssl_0rtt_done;
+    return SECSuccess;
+}
+
+SECStatus
+tls13_HandleEndOfEarlyData(sslSocket *ss)
+{
+    SECStatus rv;
+
+    if (ss->version < SSL_LIBRARY_VERSION_TLS_1_3 ||
+        ss->ssl3.hs.zeroRttState != ssl_0rtt_accepted) {
+        (void)SSL3_SendAlert(ss, alert_fatal, unexpected_message);
+        PORT_SetError(SSL_ERROR_END_OF_EARLY_DATA_ALERT);
+        return SECFailure;
+    }
+
+    PORT_Assert(TLS13_IN_HS_STATE(ss, ss->opt.requestCertificate ? wait_client_cert : wait_finished));
+
+    if (IS_DTLS(ss)) {
+        /* Reset the cipher spec so that the epoch counter is properly reset. */
+        tls13_SetNullCipherSpec(ss, &ss->ssl3.crSpec);
+    }
+
+    rv = tls13_SetCipherSpec(ss, TrafficKeyHandshake,
+                             CipherSpecRead, PR_FALSE);
+    if (rv != SECSuccess) {
+        PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
+        return SECFailure;
+    }
+
+    ss->ssl3.hs.zeroRttState = ssl_0rtt_done;
+    return SECSuccess;
+}
+
+SECStatus
+tls13_HandleEarlyApplicationData(sslSocket *ss, sslBuffer *origBuf)
+{
+    TLS13EarlyData *ed;
+    SECItem it = { siBuffer, NULL, 0 };
+
+    PORT_Assert(ss->sec.isServer);
+    PORT_Assert(ss->ssl3.hs.zeroRttState == ssl_0rtt_accepted);
+    if (ss->ssl3.hs.zeroRttState != ssl_0rtt_accepted) {
+        /* Belt and suspenders. */
+        FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
+        return SECFailure;
+    }
+
+    PRINT_BUF(3, (NULL, "Received early application data",
+                  origBuf->buf, origBuf->len));
+    ed = PORT_ZNew(TLS13EarlyData);
+    if (!ed) {
+        FATAL_ERROR(ss, SEC_ERROR_NO_MEMORY, internal_error);
+        return SECFailure;
+    }
+    it.data = origBuf->buf;
+    it.len = origBuf->len;
+    if (SECITEM_CopyItem(NULL, &ed->data, &it) != SECSuccess) {
+        FATAL_ERROR(ss, SEC_ERROR_NO_MEMORY, internal_error);
+        return SECFailure;
+    }
+    PR_APPEND_LINK(&ed->link, &ss->ssl3.hs.bufferedEarlyData);
+
+    origBuf->len = 0; /* So ssl3_GatherAppDataRecord will keep looping. */
+
+    return SECSuccess;
+}
+
+PRUint16
+tls13_EncodeDraftVersion(SSL3ProtocolVersion version)
+{
+#ifdef TLS_1_3_DRAFT_VERSION
+    if (version == SSL_LIBRARY_VERSION_TLS_1_3) {
+        return 0x7f00 | TLS_1_3_DRAFT_VERSION;
+    }
+#endif
+    return (PRUint16)version;
+}
+
+/* Pick the highest version we support that is also advertised. */
+SECStatus
+tls13_NegotiateVersion(sslSocket *ss, const TLSExtension *supported_versions)
+{
+    PRUint16 version;
+    /* Make a copy so we're nondestructive*/
+    SECItem data = supported_versions->data;
+    SECItem versions;
+    SECStatus rv;
+
+    rv = ssl3_ConsumeHandshakeVariable(ss, &versions, 1,
+                                       &data.data, &data.len);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+    if (data.len || !versions.len || (versions.len & 1)) {
+        FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_CLIENT_HELLO, illegal_parameter);
+        return SECFailure;
+    }
+    for (version = ss->vrange.max; version >= ss->vrange.min; --version) {
+        PRUint16 wire = tls13_EncodeDraftVersion(version);
+        unsigned long offset;
+
+        for (offset = 0; offset < versions.len; offset += 2) {
+            PRUint16 supported =
+                (versions.data[offset] << 8) | versions.data[offset + 1];
+            if (supported == wire) {
+                ss->version = version;
+                return SECSuccess;
+            }
+        }
+    }
+
+    FATAL_ERROR(ss, SSL_ERROR_UNSUPPORTED_VERSION, protocol_version);
+    return SECFailure;
+}