/*

 * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.

 * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved

 *

 * Licensed under the OpenSSL license (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#include <limits.h>

#include <string.h>

#include <stdio.h>

#include "../ssl_local.h"

#include "statem_local.h"

#include "internal/cryptlib.h"

#include <openssl/buffer.h>

#include <openssl/objects.h>

#include <openssl/evp.h>

#include <openssl/x509.h>

/*

 * Map error codes to TLS/SSL alart types.

 */

typedef struct x509err2alert_st {

    int x509err;

    int alert;

} X509ERR2ALERT;

/* Fixed value used in the ServerHello random field to identify an HRR */

const unsigned char hrrrandom[] = {

    0xcf, 0x21, 0xad, 0x74, 0xe5, 0x9a, 0x61, 0x11, 0xbe, 0x1d, 0x8c, 0x02,

    0x1e, 0x65, 0xb8, 0x91, 0xc2, 0xa2, 0x11, 0x16, 0x7a, 0xbb, 0x8c, 0x5e,

    0x07, 0x9e, 0x09, 0xe2, 0xc8, 0xa8, 0x33, 0x9c

};

/*

 * send s->init_buf in records of type 'type' (SSL3_RT_HANDSHAKE or

 * SSL3_RT_CHANGE_CIPHER_SPEC)

 */

int ssl3_do_write(SSL *s, int type)

{

    int ret;

    size_t written = 0;

    ret = ssl3_write_bytes(s, type, &s->init_buf->data[s->init_off],

                           s->init_num, &written);

    if (ret < 0)

        return -1;

    if (type == SSL3_RT_HANDSHAKE)

        /*

         * should not be done for 'Hello Request's, but in that case we'll

         * ignore the result anyway

         * TLS1.3 KeyUpdate and NewSessionTicket do not need to be added

         */

        if (!SSL_IS_TLS13(s) || (s->statem.hand_state != TLS_ST_SW_SESSION_TICKET

                                 && s->statem.hand_state != TLS_ST_CW_KEY_UPDATE

                                 && s->statem.hand_state != TLS_ST_SW_KEY_UPDATE))

            if (!ssl3_finish_mac(s,

                                 (unsigned char *)&s->init_buf->data[s->init_off],

                                 written))

                return -1;

    if (written == s->init_num) {

        if (s->msg_callback)

            s->msg_callback(1, s->version, type, s->init_buf->data,

                            (size_t)(s->init_off + s->init_num), s,

                            s->msg_callback_arg);

        return 1;

    }

    s->init_off += written;

    s->init_num -= written;

    return 0;

}

int tls_close_construct_packet(SSL *s, WPACKET *pkt, int htype)

{

    size_t msglen;

    if ((htype != SSL3_MT_CHANGE_CIPHER_SPEC && !WPACKET_close(pkt))

            || !WPACKET_get_length(pkt, &msglen)

            || msglen > INT_MAX)

        return 0;

    s->init_num = (int)msglen;

    s->init_off = 0;

    return 1;

}

int tls_setup_handshake(SSL *s)

{

    if (!ssl3_init_finished_mac(s)) {

        /* SSLfatal() already called */

        return 0;

    }

    /* Reset any extension flags */

    memset(s->ext.extflags, 0, sizeof(s->ext.extflags));

    if (s->server) {

        STACK_OF(SSL_CIPHER) *ciphers = SSL_get_ciphers(s);

        int i, ver_min, ver_max, ok = 0;

        /*

         * Sanity check that the maximum version we accept has ciphers

         * enabled. For clients we do this check during construction of the

         * ClientHello.

         */

        if (ssl_get_min_max_version(s, &ver_min, &ver_max, NULL) != 0) {

            SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_SETUP_HANDSHAKE,

                     ERR_R_INTERNAL_ERROR);

            return 0;

        }

        for (i = 0; i < sk_SSL_CIPHER_num(ciphers); i++) {

            const SSL_CIPHER *c = sk_SSL_CIPHER_value(ciphers, i);

            if (SSL_IS_DTLS(s)) {

                if (DTLS_VERSION_GE(ver_max, c->min_dtls) &&

                        DTLS_VERSION_LE(ver_max, c->max_dtls))

                    ok = 1;

            } else if (ver_max >= c->min_tls && ver_max <= c->max_tls) {

                ok = 1;

            }

            if (ok)

                break;

        }

        if (!ok) {

            SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_SETUP_HANDSHAKE,

                     SSL_R_NO_CIPHERS_AVAILABLE);

            ERR_add_error_data(1, "No ciphers enabled for max supported "

                                  "SSL/TLS version");

            return 0;

        }

        if (SSL_IS_FIRST_HANDSHAKE(s)) {

            /* N.B. s->session_ctx == s->ctx here */

            tsan_counter(&s->session_ctx->stats.sess_accept);

        } else {

            /* N.B. s->ctx may not equal s->session_ctx */

            tsan_counter(&s->ctx->stats.sess_accept_renegotiate);

            s->s3->tmp.cert_request = 0;

        }

    } else {

        if (SSL_IS_FIRST_HANDSHAKE(s))

            tsan_counter(&s->session_ctx->stats.sess_connect);

        else

            tsan_counter(&s->session_ctx->stats.sess_connect_renegotiate);

        /* mark client_random uninitialized */

        memset(s->s3->client_random, 0, sizeof(s->s3->client_random));

        s->hit = 0;

        s->s3->tmp.cert_req = 0;

        if (SSL_IS_DTLS(s))

            s->statem.use_timer = 1;

    }

    return 1;

}

/*

 * Size of the to-be-signed TLS13 data, without the hash size itself:

 * 64 bytes of value 32, 33 context bytes, 1 byte separator

 */

#define TLS13_TBS_START_SIZE            64

#define TLS13_TBS_PREAMBLE_SIZE         (TLS13_TBS_START_SIZE + 33 + 1)

static int get_cert_verify_tbs_data(SSL *s, unsigned char *tls13tbs,

                                    void **hdata, size_t *hdatalen)

{

#ifdef CHARSET_EBCDIC

    static const char servercontext[] = { 0x54, 0x4c, 0x53, 0x20, 0x31, 0x2e,

     0x33, 0x2c, 0x20, 0x73, 0x65, 0x72, 0x76, 0x65, 0x72, 0x20, 0x43, 0x65,

     0x72, 0x74, 0x69, 0x66, 0x69, 0x63, 0x61, 0x74, 0x65, 0x56, 0x65, 0x72,

     0x69, 0x66, 0x79, 0x00 };

    static const char clientcontext[] = { 0x54, 0x4c, 0x53, 0x20, 0x31, 0x2e,

     0x33, 0x2c, 0x20, 0x63, 0x6c, 0x69, 0x65, 0x6e, 0x74, 0x20, 0x43, 0x65,

     0x72, 0x74, 0x69, 0x66, 0x69, 0x63, 0x61, 0x74, 0x65, 0x56, 0x65, 0x72,

     0x69, 0x66, 0x79, 0x00 };

#else

    static const char servercontext[] = "TLS 1.3, server CertificateVerify";

    static const char clientcontext[] = "TLS 1.3, client CertificateVerify";

#endif

    if (SSL_IS_TLS13(s)) {

        size_t hashlen;

        /* Set the first 64 bytes of to-be-signed data to octet 32 */

        memset(tls13tbs, 32, TLS13_TBS_START_SIZE);

        /* This copies the 33 bytes of context plus the 0 separator byte */

        if (s->statem.hand_state == TLS_ST_CR_CERT_VRFY

                 || s->statem.hand_state == TLS_ST_SW_CERT_VRFY)

            strcpy((char *)tls13tbs + TLS13_TBS_START_SIZE, servercontext);

        else

            strcpy((char *)tls13tbs + TLS13_TBS_START_SIZE, clientcontext);

        /*

         * If we're currently reading then we need to use the saved handshake

         * hash value. We can't use the current handshake hash state because

         * that includes the CertVerify itself.

         */

        if (s->statem.hand_state == TLS_ST_CR_CERT_VRFY

                || s->statem.hand_state == TLS_ST_SR_CERT_VRFY) {

            memcpy(tls13tbs + TLS13_TBS_PREAMBLE_SIZE, s->cert_verify_hash,

                   s->cert_verify_hash_len);

            hashlen = s->cert_verify_hash_len;

        } else if (!ssl_handshake_hash(s, tls13tbs + TLS13_TBS_PREAMBLE_SIZE,

                                       EVP_MAX_MD_SIZE, &hashlen)) {

            /* SSLfatal() already called */

            return 0;

        }

        *hdata = tls13tbs;

        *hdatalen = TLS13_TBS_PREAMBLE_SIZE + hashlen;

    } else {

        size_t retlen;

        long retlen_l;

        retlen = retlen_l = BIO_get_mem_data(s->s3->handshake_buffer, hdata);

        if (retlen_l <= 0) {

            SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_GET_CERT_VERIFY_TBS_DATA,

                     ERR_R_INTERNAL_ERROR);

            return 0;

        }

        *hdatalen = retlen;

    }

    return 1;

}

int tls_construct_cert_verify(SSL *s, WPACKET *pkt)

{

    EVP_PKEY *pkey = NULL;

    const EVP_MD *md = NULL;

    EVP_MD_CTX *mctx = NULL;

    EVP_PKEY_CTX *pctx = NULL;

    size_t hdatalen = 0, siglen = 0;

    void *hdata;

    unsigned char *sig = NULL;

    unsigned char tls13tbs[TLS13_TBS_PREAMBLE_SIZE + EVP_MAX_MD_SIZE];

    const SIGALG_LOOKUP *lu = s->s3->tmp.sigalg;

    if (lu == NULL || s->s3->tmp.cert == NULL) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CERT_VERIFY,

                 ERR_R_INTERNAL_ERROR);

        goto err;

    }

    pkey = s->s3->tmp.cert->privatekey;

    if (pkey == NULL || !tls1_lookup_md(lu, &md)) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CERT_VERIFY,

                 ERR_R_INTERNAL_ERROR);

        goto err;

    }

    mctx = EVP_MD_CTX_new();

    if (mctx == NULL) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CERT_VERIFY,

                 ERR_R_MALLOC_FAILURE);

        goto err;

    }

    /* Get the data to be signed */

    if (!get_cert_verify_tbs_data(s, tls13tbs, &hdata, &hdatalen)) {

        /* SSLfatal() already called */

        goto err;

    }

    if (SSL_USE_SIGALGS(s) && !WPACKET_put_bytes_u16(pkt, lu->sigalg)) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CERT_VERIFY,

                 ERR_R_INTERNAL_ERROR);

        goto err;

    }

    siglen = EVP_PKEY_size(pkey);

    sig = OPENSSL_malloc(siglen);

    if (sig == NULL) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CERT_VERIFY,

                 ERR_R_MALLOC_FAILURE);

        goto err;

    }

    if (EVP_DigestSignInit(mctx, &pctx, md, NULL, pkey) <= 0) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CERT_VERIFY,

                 ERR_R_EVP_LIB);

        goto err;

    }

    if (lu->sig == EVP_PKEY_RSA_PSS) {

        if (EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PSS_PADDING) <= 0

            || EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx,

                                                RSA_PSS_SALTLEN_DIGEST) <= 0) {

            SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CERT_VERIFY,

                     ERR_R_EVP_LIB);

            goto err;

        }

    }

    if (s->version == SSL3_VERSION) {

        if (EVP_DigestSignUpdate(mctx, hdata, hdatalen) <= 0

            || !EVP_MD_CTX_ctrl(mctx, EVP_CTRL_SSL3_MASTER_SECRET,

                                (int)s->session->master_key_length,

                                s->session->master_key)

            || EVP_DigestSignFinal(mctx, sig, &siglen) <= 0) {

            SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CERT_VERIFY,

                     ERR_R_EVP_LIB);

            goto err;

        }

    } else if (EVP_DigestSign(mctx, sig, &siglen, hdata, hdatalen) <= 0) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CERT_VERIFY,

                 ERR_R_EVP_LIB);

        goto err;

    }

#ifndef OPENSSL_NO_GOST

    {

        int pktype = lu->sig;

        if (pktype == NID_id_GostR3410_2001

            || pktype == NID_id_GostR3410_2012_256

            || pktype == NID_id_GostR3410_2012_512)

            BUF_reverse(sig, NULL, siglen);

    }

#endif

    if (!WPACKET_sub_memcpy_u16(pkt, sig, siglen)) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CERT_VERIFY,

                 ERR_R_INTERNAL_ERROR);

        goto err;

    }

    /* Digest cached records and discard handshake buffer */

    if (!ssl3_digest_cached_records(s, 0)) {

        /* SSLfatal() already called */

        goto err;

    }

    OPENSSL_free(sig);

    EVP_MD_CTX_free(mctx);

    return 1;

 err:

    OPENSSL_free(sig);

    EVP_MD_CTX_free(mctx);

    return 0;

}

MSG_PROCESS_RETURN tls_process_cert_verify(SSL *s, PACKET *pkt)

{

    EVP_PKEY *pkey = NULL;

    const unsigned char *data;

#ifndef OPENSSL_NO_GOST

    unsigned char *gost_data = NULL;

#endif

    MSG_PROCESS_RETURN ret = MSG_PROCESS_ERROR;

    int j;

    unsigned int len;

    X509 *peer;

    const EVP_MD *md = NULL;

    size_t hdatalen = 0;

    void *hdata;

    unsigned char tls13tbs[TLS13_TBS_PREAMBLE_SIZE + EVP_MAX_MD_SIZE];

    EVP_MD_CTX *mctx = EVP_MD_CTX_new();

    EVP_PKEY_CTX *pctx = NULL;

    if (mctx == NULL) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CERT_VERIFY,

                 ERR_R_MALLOC_FAILURE);

        goto err;

    }

    peer = s->session->peer;

    pkey = X509_get0_pubkey(peer);

    if (pkey == NULL) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CERT_VERIFY,

                 ERR_R_INTERNAL_ERROR);

        goto err;

    }

    if (ssl_cert_lookup_by_pkey(pkey, NULL) == NULL) {

        SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PROCESS_CERT_VERIFY,

                 SSL_R_SIGNATURE_FOR_NON_SIGNING_CERTIFICATE);

        goto err;

    }

    if (SSL_USE_SIGALGS(s)) {

        unsigned int sigalg;

        if (!PACKET_get_net_2(pkt, &sigalg)) {

            SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CERT_VERIFY,

                     SSL_R_BAD_PACKET);

            goto err;

        }

        if (tls12_check_peer_sigalg(s, sigalg, pkey) <= 0) {

            /* SSLfatal() already called */

            goto err;

        }

    } else if (!tls1_set_peer_legacy_sigalg(s, pkey)) {

            SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CERT_VERIFY,

                     ERR_R_INTERNAL_ERROR);

            goto err;

    }

    if (!tls1_lookup_md(s->s3->tmp.peer_sigalg, &md)) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CERT_VERIFY,

                 ERR_R_INTERNAL_ERROR);

        goto err;

    }

#ifdef SSL_DEBUG

    if (SSL_USE_SIGALGS(s))

        fprintf(stderr, "USING TLSv1.2 HASH %s\n",

                md == NULL ? "n/a" : EVP_MD_name(md));

#endif

    /* Check for broken implementations of GOST ciphersuites */

    /*

     * If key is GOST and len is exactly 64 or 128, it is signature without

     * length field (CryptoPro implementations at least till TLS 1.2)

     */

#ifndef OPENSSL_NO_GOST

    if (!SSL_USE_SIGALGS(s)

        && ((PACKET_remaining(pkt) == 64

             && (EVP_PKEY_id(pkey) == NID_id_GostR3410_2001

                 || EVP_PKEY_id(pkey) == NID_id_GostR3410_2012_256))

            || (PACKET_remaining(pkt) == 128

                && EVP_PKEY_id(pkey) == NID_id_GostR3410_2012_512))) {

        len = PACKET_remaining(pkt);

    } else

#endif

    if (!PACKET_get_net_2(pkt, &len)) {

        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CERT_VERIFY,

                 SSL_R_LENGTH_MISMATCH);

        goto err;

    }

    j = EVP_PKEY_size(pkey);

    if (((int)len > j) || ((int)PACKET_remaining(pkt) > j)

        || (PACKET_remaining(pkt) == 0)) {

        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CERT_VERIFY,

                 SSL_R_WRONG_SIGNATURE_SIZE);

        goto err;

    }

    if (!PACKET_get_bytes(pkt, &data, len)) {

        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CERT_VERIFY,

                 SSL_R_LENGTH_MISMATCH);

        goto err;

    }

    if (!get_cert_verify_tbs_data(s, tls13tbs, &hdata, &hdatalen)) {

        /* SSLfatal() already called */

        goto err;

    }

#ifdef SSL_DEBUG

    fprintf(stderr, "Using client verify alg %s\n",

            md == NULL ? "n/a" : EVP_MD_name(md));

#endif

    if (EVP_DigestVerifyInit(mctx, &pctx, md, NULL, pkey) <= 0) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CERT_VERIFY,

                 ERR_R_EVP_LIB);

        goto err;

    }

#ifndef OPENSSL_NO_GOST

    {

        int pktype = EVP_PKEY_id(pkey);

        if (pktype == NID_id_GostR3410_2001

            || pktype == NID_id_GostR3410_2012_256

            || pktype == NID_id_GostR3410_2012_512) {

            if ((gost_data = OPENSSL_malloc(len)) == NULL) {

                SSLfatal(s, SSL_AD_INTERNAL_ERROR,

                         SSL_F_TLS_PROCESS_CERT_VERIFY, ERR_R_MALLOC_FAILURE);

                goto err;

            }

            BUF_reverse(gost_data, data, len);

            data = gost_data;

        }

    }

#endif

    if (SSL_USE_PSS(s)) {

        if (EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PSS_PADDING) <= 0

            || EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx,

                                                RSA_PSS_SALTLEN_DIGEST) <= 0) {

            SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CERT_VERIFY,

                     ERR_R_EVP_LIB);

            goto err;

        }

    }

    if (s->version == SSL3_VERSION) {

        if (EVP_DigestVerifyUpdate(mctx, hdata, hdatalen) <= 0

                || !EVP_MD_CTX_ctrl(mctx, EVP_CTRL_SSL3_MASTER_SECRET,

                                    (int)s->session->master_key_length,

                                    s->session->master_key)) {

            SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CERT_VERIFY,

                     ERR_R_EVP_LIB);

            goto err;

        }

        if (EVP_DigestVerifyFinal(mctx, data, len) <= 0) {

            SSLfatal(s, SSL_AD_DECRYPT_ERROR, SSL_F_TLS_PROCESS_CERT_VERIFY,

                     SSL_R_BAD_SIGNATURE);

            goto err;

        }

    } else {

        j = EVP_DigestVerify(mctx, data, len, hdata, hdatalen);

        if (j <= 0) {

            SSLfatal(s, SSL_AD_DECRYPT_ERROR, SSL_F_TLS_PROCESS_CERT_VERIFY,

                     SSL_R_BAD_SIGNATURE);

            goto err;

        }

    }

    /*

     * In TLSv1.3 on the client side we make sure we prepare the client

     * certificate after the CertVerify instead of when we get the

     * CertificateRequest. This is because in TLSv1.3 the CertificateRequest

     * comes *before* the Certificate message. In TLSv1.2 it comes after. We

     * want to make sure that SSL_get_peer_certificate() will return the actual

     * server certificate from the client_cert_cb callback.

     */

    if (!s->server && SSL_IS_TLS13(s) && s->s3->tmp.cert_req == 1)

        ret = MSG_PROCESS_CONTINUE_PROCESSING;

    else

        ret = MSG_PROCESS_CONTINUE_READING;

 err:

    BIO_free(s->s3->handshake_buffer);

    s->s3->handshake_buffer = NULL;

    EVP_MD_CTX_free(mctx);

#ifndef OPENSSL_NO_GOST

    OPENSSL_free(gost_data);

#endif

    return ret;

}

int tls_construct_finished(SSL *s, WPACKET *pkt)

{

    size_t finish_md_len;

    const char *sender;

    size_t slen;

    /* This is a real handshake so make sure we clean it up at the end */

    if (!s->server && s->post_handshake_auth != SSL_PHA_REQUESTED)

        s->statem.cleanuphand = 1;

    /*

     * We only change the keys if we didn't already do this when we sent the

     * client certificate

     */

    if (SSL_IS_TLS13(s)

            && !s->server

            && s->s3->tmp.cert_req == 0

            && (!s->method->ssl3_enc->change_cipher_state(s,

                    SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_CLIENT_WRITE))) {;

        /* SSLfatal() already called */

        return 0;

    }

    if (s->server) {

        sender = s->method->ssl3_enc->server_finished_label;

        slen = s->method->ssl3_enc->server_finished_label_len;

    } else {

        sender = s->method->ssl3_enc->client_finished_label;

        slen = s->method->ssl3_enc->client_finished_label_len;

    }

    finish_md_len = s->method->ssl3_enc->final_finish_mac(s,

                                                          sender, slen,

                                                          s->s3->tmp.finish_md);

    if (finish_md_len == 0) {

        /* SSLfatal() already called */

        return 0;

    }

    s->s3->tmp.finish_md_len = finish_md_len;

    if (!WPACKET_memcpy(pkt, s->s3->tmp.finish_md, finish_md_len)) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_FINISHED,

                 ERR_R_INTERNAL_ERROR);

        return 0;

    }

    /*

     * Log the master secret, if logging is enabled. We don't log it for

     * TLSv1.3: there's a different key schedule for that.

     */

    if (!SSL_IS_TLS13(s) && !ssl_log_secret(s, MASTER_SECRET_LABEL,

                                            s->session->master_key,

                                            s->session->master_key_length)) {

        /* SSLfatal() already called */

        return 0;

    }

    /*

     * Copy the finished so we can use it for renegotiation checks

     */

    if (!ossl_assert(finish_md_len <= EVP_MAX_MD_SIZE)) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_FINISHED,

                 ERR_R_INTERNAL_ERROR);

        return 0;

    }

    if (!s->server) {

        memcpy(s->s3->previous_client_finished, s->s3->tmp.finish_md,

               finish_md_len);

        s->s3->previous_client_finished_len = finish_md_len;

    } else {

        memcpy(s->s3->previous_server_finished, s->s3->tmp.finish_md,

               finish_md_len);

        s->s3->previous_server_finished_len = finish_md_len;

    }

    return 1;

}

int tls_construct_key_update(SSL *s, WPACKET *pkt)

{

    if (!WPACKET_put_bytes_u8(pkt, s->key_update)) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_KEY_UPDATE,

                 ERR_R_INTERNAL_ERROR);

        return 0;

    }

    s->key_update = SSL_KEY_UPDATE_NONE;

    return 1;

}

MSG_PROCESS_RETURN tls_process_key_update(SSL *s, PACKET *pkt)

{

    unsigned int updatetype;

    /*

     * A KeyUpdate message signals a key change so the end of the message must

     * be on a record boundary.

     */

    if (RECORD_LAYER_processed_read_pending(&s->rlayer)) {

        SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_TLS_PROCESS_KEY_UPDATE,

                 SSL_R_NOT_ON_RECORD_BOUNDARY);

        return MSG_PROCESS_ERROR;

    }

    if (!PACKET_get_1(pkt, &updatetype)

            || PACKET_remaining(pkt) != 0) {

        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_KEY_UPDATE,

                 SSL_R_BAD_KEY_UPDATE);

        return MSG_PROCESS_ERROR;

    }

    /*

     * There are only two defined key update types. Fail if we get a value we

     * didn't recognise.

     */

    if (updatetype != SSL_KEY_UPDATE_NOT_REQUESTED

            && updatetype != SSL_KEY_UPDATE_REQUESTED) {

        SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PROCESS_KEY_UPDATE,

                 SSL_R_BAD_KEY_UPDATE);

        return MSG_PROCESS_ERROR;

    }

    /*

     * If we get a request for us to update our sending keys too then, we need

     * to additionally send a KeyUpdate message. However that message should

     * not also request an update (otherwise we get into an infinite loop).

     */

    if (updatetype == SSL_KEY_UPDATE_REQUESTED)

        s->key_update = SSL_KEY_UPDATE_NOT_REQUESTED;

    if (!tls13_update_key(s, 0)) {

        /* SSLfatal() already called */

        return MSG_PROCESS_ERROR;

    }

    return MSG_PROCESS_FINISHED_READING;

}

/*

 * ssl3_take_mac calculates the Finished MAC for the handshakes messages seen

 * to far.

 */

int ssl3_take_mac(SSL *s)

{

    const char *sender;

    size_t slen;

    if (!s->server) {

        sender = s->method->ssl3_enc->server_finished_label;

        slen = s->method->ssl3_enc->server_finished_label_len;

    } else {

        sender = s->method->ssl3_enc->client_finished_label;

        slen = s->method->ssl3_enc->client_finished_label_len;

    }

    s->s3->tmp.peer_finish_md_len =

        s->method->ssl3_enc->final_finish_mac(s, sender, slen,

                                              s->s3->tmp.peer_finish_md);

    if (s->s3->tmp.peer_finish_md_len == 0) {

        /* SSLfatal() already called */

        return 0;

    }

    return 1;

}

MSG_PROCESS_RETURN tls_process_change_cipher_spec(SSL *s, PACKET *pkt)

{

    size_t remain;

    remain = PACKET_remaining(pkt);

    /*

     * 'Change Cipher Spec' is just a single byte, which should already have

     * been consumed by ssl_get_message() so there should be no bytes left,

     * unless we're using DTLS1_BAD_VER, which has an extra 2 bytes

     */

    if (SSL_IS_DTLS(s)) {

        if ((s->version == DTLS1_BAD_VER

             && remain != DTLS1_CCS_HEADER_LENGTH + 1)

            || (s->version != DTLS1_BAD_VER

                && remain != DTLS1_CCS_HEADER_LENGTH - 1)) {

            SSLfatal(s, SSL_AD_DECODE_ERROR,

                     SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC,

                    SSL_R_BAD_CHANGE_CIPHER_SPEC);

            return MSG_PROCESS_ERROR;

        }

    } else {

        if (remain != 0) {

            SSLfatal(s, SSL_AD_DECODE_ERROR,

                     SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC,

                     SSL_R_BAD_CHANGE_CIPHER_SPEC);

            return MSG_PROCESS_ERROR;

        }

    }

    /* Check we have a cipher to change to */

    if (s->s3->tmp.new_cipher == NULL) {

        SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE,

                 SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC, SSL_R_CCS_RECEIVED_EARLY);

        return MSG_PROCESS_ERROR;

    }

    s->s3->change_cipher_spec = 1;

    if (!ssl3_do_change_cipher_spec(s)) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC,

                 ERR_R_INTERNAL_ERROR);

        return MSG_PROCESS_ERROR;

    }

    if (SSL_IS_DTLS(s)) {

        dtls1_reset_seq_numbers(s, SSL3_CC_READ);

        if (s->version == DTLS1_BAD_VER)

            s->d1->handshake_read_seq++;

#ifndef OPENSSL_NO_SCTP

        /*

         * Remember that a CCS has been received, so that an old key of

         * SCTP-Auth can be deleted when a CCS is sent. Will be ignored if no

         * SCTP is used

         */

        BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL);

#endif

    }

    return MSG_PROCESS_CONTINUE_READING;

}

MSG_PROCESS_RETURN tls_process_finished(SSL *s, PACKET *pkt)

{

    size_t md_len;

    /* This is a real handshake so make sure we clean it up at the end */

    if (s->server) {

        /*

        * To get this far we must have read encrypted data from the client. We

        * no longer tolerate unencrypted alerts. This value is ignored if less

        * than TLSv1.3

        */

        s->statem.enc_read_state = ENC_READ_STATE_VALID;

        if (s->post_handshake_auth != SSL_PHA_REQUESTED)

            s->statem.cleanuphand = 1;

        if (SSL_IS_TLS13(s) && !tls13_save_handshake_digest_for_pha(s)) {

                /* SSLfatal() already called */

                return MSG_PROCESS_ERROR;

        }

    }

    /*

     * In TLSv1.3 a Finished message signals a key change so the end of the

     * message must be on a record boundary.

     */

    if (SSL_IS_TLS13(s) && RECORD_LAYER_processed_read_pending(&s->rlayer)) {

        SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_TLS_PROCESS_FINISHED,

                 SSL_R_NOT_ON_RECORD_BOUNDARY);

        return MSG_PROCESS_ERROR;

    }

    /* If this occurs, we have missed a message */

    if (!SSL_IS_TLS13(s) && !s->s3->change_cipher_spec) {

        SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_TLS_PROCESS_FINISHED,

                 SSL_R_GOT_A_FIN_BEFORE_A_CCS);

        return MSG_PROCESS_ERROR;

    }

    s->s3->change_cipher_spec = 0;

    md_len = s->s3->tmp.peer_finish_md_len;

    if (md_len != PACKET_remaining(pkt)) {

        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_FINISHED,

                 SSL_R_BAD_DIGEST_LENGTH);

        return MSG_PROCESS_ERROR;

    }

    if (CRYPTO_memcmp(PACKET_data(pkt), s->s3->tmp.peer_finish_md,

                      md_len) != 0) {

        SSLfatal(s, SSL_AD_DECRYPT_ERROR, SSL_F_TLS_PROCESS_FINISHED,

                 SSL_R_DIGEST_CHECK_FAILED);

        return MSG_PROCESS_ERROR;

    }

    /*

     * Copy the finished so we can use it for renegotiation checks

     */

    if (!ossl_assert(md_len <= EVP_MAX_MD_SIZE)) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_FINISHED,

                 ERR_R_INTERNAL_ERROR);

        return MSG_PROCESS_ERROR;

    }

    if (s->server) {

        memcpy(s->s3->previous_client_finished, s->s3->tmp.peer_finish_md,

               md_len);

        s->s3->previous_client_finished_len = md_len;

    } else {

        memcpy(s->s3->previous_server_finished, s->s3->tmp.peer_finish_md,

               md_len);

        s->s3->previous_server_finished_len = md_len;

    }

    /*

     * In TLS1.3 we also have to change cipher state and do any final processing

     * of the initial server flight (if we are a client)

     */

    if (SSL_IS_TLS13(s)) {

        if (s->server) {

            if (s->post_handshake_auth != SSL_PHA_REQUESTED &&

                    !s->method->ssl3_enc->change_cipher_state(s,

                    SSL3_CC_APPLICATION | SSL3_CHANGE_CIPHER_SERVER_READ)) {

                /* SSLfatal() already called */

                return MSG_PROCESS_ERROR;

            }

        } else {

            /* TLS 1.3 gets the secret size from the handshake md */

            size_t dummy;

            if (!s->method->ssl3_enc->generate_master_secret(s,

                    s->master_secret, s->handshake_secret, 0,

                    &dummy)) {

                /* SSLfatal() already called */

                return MSG_PROCESS_ERROR;

            }

            if (!s->method->ssl3_enc->change_cipher_state(s,

                    SSL3_CC_APPLICATION | SSL3_CHANGE_CIPHER_CLIENT_READ)) {

                /* SSLfatal() already called */

                return MSG_PROCESS_ERROR;

            }

            if (!tls_process_initial_server_flight(s)) {

                /* SSLfatal() already called */

                return MSG_PROCESS_ERROR;

            }

        }

    }

    return MSG_PROCESS_FINISHED_READING;

}

int tls_construct_change_cipher_spec(SSL *s, WPACKET *pkt)

{

    if (!WPACKET_put_bytes_u8(pkt, SSL3_MT_CCS)) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR,

                 SSL_F_TLS_CONSTRUCT_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);

        return 0;

    }

    return 1;

}