/*

 * Copyright 2016-2022 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the Apache License 2.0 (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 <stdlib.h>

#include "ssl_local.h"

#include "internal/ktls.h"

#include "record/record_local.h"

#include "internal/cryptlib.h"

#include <openssl/evp.h>

#include <openssl/kdf.h>

#include <openssl/core_names.h>

#define TLS13_MAX_LABEL_LEN     249

#ifdef CHARSET_EBCDIC

static const unsigned char label_prefix[] = { 0x74, 0x6C, 0x73, 0x31, 0x33, 0x20, 0x00 };

#else

static const unsigned char label_prefix[] = "tls13 ";

#endif

/*

 * Given a |secret|; a |label| of length |labellen|; and |data| of length

 * |datalen| (e.g. typically a hash of the handshake messages), derive a new

 * secret |outlen| bytes long and store it in the location pointed to be |out|.

 * The |data| value may be zero length. Any errors will be treated as fatal if

 * |fatal| is set. Returns 1 on success  0 on failure.

 */

int tls13_hkdf_expand(SSL *s, const EVP_MD *md, const unsigned char *secret,

                      const unsigned char *label, size_t labellen,

                      const unsigned char *data, size_t datalen,

                      unsigned char *out, size_t outlen, int fatal)

{

    EVP_KDF *kdf = EVP_KDF_fetch(s->ctx->libctx, OSSL_KDF_NAME_TLS1_3_KDF,

                                 s->ctx->propq);

    EVP_KDF_CTX *kctx;

    OSSL_PARAM params[7], *p = params;

    int mode = EVP_PKEY_HKDEF_MODE_EXPAND_ONLY;

    const char *mdname = EVP_MD_get0_name(md);

    int ret;

    size_t hashlen;

    kctx = EVP_KDF_CTX_new(kdf);

    EVP_KDF_free(kdf);

    if (kctx == NULL)

        return 0;

    if (labellen > TLS13_MAX_LABEL_LEN) {

        if (fatal) {

            SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);

        } else {

            /*

             * Probably we have been called from SSL_export_keying_material(),

             * or SSL_export_keying_material_early().

             */

            ERR_raise(ERR_LIB_SSL, SSL_R_TLS_ILLEGAL_EXPORTER_LABEL);

        }

        EVP_KDF_CTX_free(kctx);

        return 0;

    }

    if ((ret = EVP_MD_get_size(md)) <= 0) {

        EVP_KDF_CTX_free(kctx);

        if (fatal)

            SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);

        else

            ERR_raise(ERR_LIB_SSL, ERR_R_INTERNAL_ERROR);

        return 0;

    }

    hashlen = (size_t)ret;

    *p++ = OSSL_PARAM_construct_int(OSSL_KDF_PARAM_MODE, &mode);

    *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,

                                            (char *)mdname, 0);

    *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY,

                                             (unsigned char *)secret, hashlen);

    *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_PREFIX,

                                             (unsigned char *)label_prefix,

                                             sizeof(label_prefix) - 1);

    *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_LABEL,

                                             (unsigned char *)label, labellen);

    if (data != NULL)

        *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_DATA,

                                                 (unsigned char *)data,

                                                 datalen);

    *p++ = OSSL_PARAM_construct_end();

    ret = EVP_KDF_derive(kctx, out, outlen, params) <= 0;

    EVP_KDF_CTX_free(kctx);

    if (ret != 0) {

        if (fatal)

            SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);

        else

            ERR_raise(ERR_LIB_SSL, ERR_R_INTERNAL_ERROR);

    }

    return ret == 0;

}

/*

 * Given a |secret| generate a |key| of length |keylen| bytes. Returns 1 on

 * success  0 on failure.

 */

int tls13_derive_key(SSL *s, const EVP_MD *md, const unsigned char *secret,

                     unsigned char *key, size_t keylen)

{

#ifdef CHARSET_EBCDIC

  static const unsigned char keylabel[] ={ 0x6B, 0x65, 0x79, 0x00 };

#else

  static const unsigned char keylabel[] = "key";

#endif

    return tls13_hkdf_expand(s, md, secret, keylabel, sizeof(keylabel) - 1,

                             NULL, 0, key, keylen, 1);

}

/*

 * Given a |secret| generate an |iv| of length |ivlen| bytes. Returns 1 on

 * success  0 on failure.

 */

int tls13_derive_iv(SSL *s, const EVP_MD *md, const unsigned char *secret,

                    unsigned char *iv, size_t ivlen)

{

#ifdef CHARSET_EBCDIC

  static const unsigned char ivlabel[] = { 0x69, 0x76, 0x00 };

#else

  static const unsigned char ivlabel[] = "iv";

#endif

    return tls13_hkdf_expand(s, md, secret, ivlabel, sizeof(ivlabel) - 1,

                             NULL, 0, iv, ivlen, 1);

}

int tls13_derive_finishedkey(SSL *s, const EVP_MD *md,

                             const unsigned char *secret,

                             unsigned char *fin, size_t finlen)

{

#ifdef CHARSET_EBCDIC

  static const unsigned char finishedlabel[] = { 0x66, 0x69, 0x6E, 0x69, 0x73, 0x68, 0x65, 0x64, 0x00 };

#else

  static const unsigned char finishedlabel[] = "finished";

#endif

    return tls13_hkdf_expand(s, md, secret, finishedlabel,

                             sizeof(finishedlabel) - 1, NULL, 0, fin, finlen, 1);

}

/*

 * Given the previous secret |prevsecret| and a new input secret |insecret| of

 * length |insecretlen|, generate a new secret and store it in the location

 * pointed to by |outsecret|. Returns 1 on success  0 on failure.

 */

int tls13_generate_secret(SSL *s, const EVP_MD *md,

                          const unsigned char *prevsecret,

                          const unsigned char *insecret,

                          size_t insecretlen,

                          unsigned char *outsecret)

{

    size_t mdlen;

    int mdleni;

    int ret;

    EVP_KDF *kdf;

    EVP_KDF_CTX *kctx;

    OSSL_PARAM params[7], *p = params;

    int mode = EVP_PKEY_HKDEF_MODE_EXTRACT_ONLY;

    const char *mdname = EVP_MD_get0_name(md);

#ifdef CHARSET_EBCDIC

    static const char derived_secret_label[] = { 0x64, 0x65, 0x72, 0x69, 0x76, 0x65, 0x64, 0x00 };

#else

    static const char derived_secret_label[] = "derived";

#endif

    kdf = EVP_KDF_fetch(s->ctx->libctx, OSSL_KDF_NAME_TLS1_3_KDF, s->ctx->propq);

    kctx = EVP_KDF_CTX_new(kdf);

    EVP_KDF_free(kdf);

    if (kctx == NULL) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);

        return 0;

    }

    mdleni = EVP_MD_get_size(md);

    /* Ensure cast to size_t is safe */

    if (!ossl_assert(mdleni >= 0)) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);

        EVP_KDF_CTX_free(kctx);

        return 0;

    }

    mdlen = (size_t)mdleni;

    *p++ = OSSL_PARAM_construct_int(OSSL_KDF_PARAM_MODE, &mode);

    *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,

                                            (char *)mdname, 0);

    if (insecret != NULL)

        *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY,

                                                 (unsigned char *)insecret,

                                                 insecretlen);

    if (prevsecret != NULL)

        *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_SALT,

                                                 (unsigned char *)prevsecret, mdlen);

    *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_PREFIX,

                                             (unsigned char *)label_prefix,

                                             sizeof(label_prefix) - 1);

    *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_LABEL,

                                             (unsigned char *)derived_secret_label,

                                             sizeof(derived_secret_label) - 1);

    *p++ = OSSL_PARAM_construct_end();

    ret = EVP_KDF_derive(kctx, outsecret, mdlen, params) <= 0;

    if (ret != 0)

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);

    EVP_KDF_CTX_free(kctx);

    return ret == 0;

}

/*

 * Given an input secret |insecret| of length |insecretlen| generate the

 * handshake secret. This requires the early secret to already have been

 * generated. Returns 1 on success  0 on failure.

 */

int tls13_generate_handshake_secret(SSL *s, const unsigned char *insecret,

                                size_t insecretlen)

{

    /* Calls SSLfatal() if required */

    return tls13_generate_secret(s, ssl_handshake_md(s), s->early_secret,

                                 insecret, insecretlen,

                                 (unsigned char *)&s->handshake_secret);

}

/*

 * Given the handshake secret |prev| of length |prevlen| generate the master

 * secret and store its length in |*secret_size|. Returns 1 on success  0 on

 * failure.

 */

int tls13_generate_master_secret(SSL *s, unsigned char *out,

                                 unsigned char *prev, size_t prevlen,

                                 size_t *secret_size)

{

    const EVP_MD *md = ssl_handshake_md(s);

    *secret_size = EVP_MD_get_size(md);

    /* Calls SSLfatal() if required */

    return tls13_generate_secret(s, md, prev, NULL, 0, out);

}

/*

 * Generates the mac for the Finished message. Returns the length of the MAC or

 * 0 on error.

 */

size_t tls13_final_finish_mac(SSL *s, const char *str, size_t slen,

                             unsigned char *out)

{

    const EVP_MD *md = ssl_handshake_md(s);

    const char *mdname = EVP_MD_get0_name(md);

    unsigned char hash[EVP_MAX_MD_SIZE];

    unsigned char finsecret[EVP_MAX_MD_SIZE];

    unsigned char *key = NULL;

    size_t len = 0, hashlen;

    OSSL_PARAM params[2], *p = params;

    if (md == NULL)

        return 0;

    /* Safe to cast away const here since we're not "getting" any data */

    if (s->ctx->propq != NULL)

        *p++ = OSSL_PARAM_construct_utf8_string(OSSL_ALG_PARAM_PROPERTIES,

                                                (char *)s->ctx->propq,

                                                0);

    *p = OSSL_PARAM_construct_end();

    if (!ssl_handshake_hash(s, hash, sizeof(hash), &hashlen)) {

        /* SSLfatal() already called */

        goto err;

    }

    if (str == s->method->ssl3_enc->server_finished_label) {

        key = s->server_finished_secret;

    } else if (SSL_IS_FIRST_HANDSHAKE(s)) {

        key = s->client_finished_secret;

    } else {

        if (!tls13_derive_finishedkey(s, md,

                                      s->client_app_traffic_secret,

                                      finsecret, hashlen))

            goto err;

        key = finsecret;

    }

    if (!EVP_Q_mac(s->ctx->libctx, "HMAC", s->ctx->propq, mdname,

                   params, key, hashlen, hash, hashlen,

                   /* outsize as per sizeof(peer_finish_md) */

                   out, EVP_MAX_MD_SIZE * 2, &len)) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);

        goto err;

    }

 err:

    OPENSSL_cleanse(finsecret, sizeof(finsecret));

    return len;

}

/*

 * There isn't really a key block in TLSv1.3, but we still need this function

 * for initialising the cipher and hash. Returns 1 on success or 0 on failure.

 */

int tls13_setup_key_block(SSL *s)

{

    const EVP_CIPHER *c;

    const EVP_MD *hash;

    s->session->cipher = s->s3.tmp.new_cipher;

    if (!ssl_cipher_get_evp(s->ctx, s->session, &c, &hash, NULL, NULL, NULL,

                            0)) {

        /* Error is already recorded */

        SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR);

        return 0;

    }

    ssl_evp_cipher_free(s->s3.tmp.new_sym_enc);

    s->s3.tmp.new_sym_enc = c;

    ssl_evp_md_free(s->s3.tmp.new_hash);

    s->s3.tmp.new_hash = hash;

    return 1;

}

static int derive_secret_key_and_iv(SSL *s, int sending, const EVP_MD *md,

                                    const EVP_CIPHER *ciph,

                                    const unsigned char *insecret,

                                    const unsigned char *hash,

                                    const unsigned char *label,

                                    size_t labellen, unsigned char *secret,

                                    unsigned char *key, unsigned char *iv,

                                    EVP_CIPHER_CTX *ciph_ctx)

{

    size_t ivlen, keylen, taglen;

    int hashleni = EVP_MD_get_size(md);

    size_t hashlen;

    /* Ensure cast to size_t is safe */

    if (!ossl_assert(hashleni >= 0)) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);

        return 0;

    }

    hashlen = (size_t)hashleni;

    if (!tls13_hkdf_expand(s, md, insecret, label, labellen, hash, hashlen,

                           secret, hashlen, 1)) {

        /* SSLfatal() already called */

        return 0;

    }

    keylen = EVP_CIPHER_get_key_length(ciph);

    if (EVP_CIPHER_get_mode(ciph) == EVP_CIPH_CCM_MODE) {

        uint32_t algenc;

        ivlen = EVP_CCM_TLS_IV_LEN;

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

            algenc = s->s3.tmp.new_cipher->algorithm_enc;

        } else if (s->session->cipher != NULL) {

            /* We've not selected a cipher yet - we must be doing early data */

            algenc = s->session->cipher->algorithm_enc;

        } else if (s->psksession != NULL && s->psksession->cipher != NULL) {

            /* We must be doing early data with out-of-band PSK */

            algenc = s->psksession->cipher->algorithm_enc;

        } else {

            SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);

            return 0;

        }

        if (algenc & (SSL_AES128CCM8 | SSL_AES256CCM8))

            taglen = EVP_CCM8_TLS_TAG_LEN;

         else

            taglen = EVP_CCM_TLS_TAG_LEN;

    } else {

        ivlen = EVP_CIPHER_get_iv_length(ciph);

        taglen = 0;

    }

    if (!tls13_derive_key(s, md, secret, key, keylen)

            || !tls13_derive_iv(s, md, secret, iv, ivlen)) {

        /* SSLfatal() already called */

        return 0;

    }

    if (EVP_CipherInit_ex(ciph_ctx, ciph, NULL, NULL, NULL, sending) <= 0

        || EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_AEAD_SET_IVLEN, ivlen, NULL) <= 0

        || (taglen != 0 && EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_AEAD_SET_TAG,

                                                taglen, NULL) <= 0)

        || EVP_CipherInit_ex(ciph_ctx, NULL, NULL, key, NULL, -1) <= 0) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);

        return 0;

    }

    return 1;

}

int tls13_change_cipher_state(SSL *s, int which)

{

#ifdef CHARSET_EBCDIC

  static const unsigned char client_early_traffic[]       = {0x63, 0x20, 0x65, 0x20,       /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};

  static const unsigned char client_handshake_traffic[]   = {0x63, 0x20, 0x68, 0x73, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};

  static const unsigned char client_application_traffic[] = {0x63, 0x20, 0x61, 0x70, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};

  static const unsigned char server_handshake_traffic[]   = {0x73, 0x20, 0x68, 0x73, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};

  static const unsigned char server_application_traffic[] = {0x73, 0x20, 0x61, 0x70, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};

  static const unsigned char exporter_master_secret[] = {0x65, 0x78, 0x70, 0x20,                    /* master*/  0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};

  static const unsigned char resumption_master_secret[] = {0x72, 0x65, 0x73, 0x20,                  /* master*/  0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};

  static const unsigned char early_exporter_master_secret[] = {0x65, 0x20, 0x65, 0x78, 0x70, 0x20,  /* master*/  0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};

#else

    static const unsigned char client_early_traffic[] = "c e traffic";

    static const unsigned char client_handshake_traffic[] = "c hs traffic";

    static const unsigned char client_application_traffic[] = "c ap traffic";

    static const unsigned char server_handshake_traffic[] = "s hs traffic";

    static const unsigned char server_application_traffic[] = "s ap traffic";

    static const unsigned char exporter_master_secret[] = "exp master";

    static const unsigned char resumption_master_secret[] = "res master";

    static const unsigned char early_exporter_master_secret[] = "e exp master";

#endif

    unsigned char *iv;

    unsigned char key[EVP_MAX_KEY_LENGTH];

    unsigned char secret[EVP_MAX_MD_SIZE];

    unsigned char hashval[EVP_MAX_MD_SIZE];

    unsigned char *hash = hashval;

    unsigned char *insecret;

    unsigned char *finsecret = NULL;

    const char *log_label = NULL;

    EVP_CIPHER_CTX *ciph_ctx;

    size_t finsecretlen = 0;

    const unsigned char *label;

    size_t labellen, hashlen = 0;

    int ret = 0;

    const EVP_MD *md = NULL;

    const EVP_CIPHER *cipher = NULL;

#if !defined(OPENSSL_NO_KTLS) && defined(OPENSSL_KTLS_TLS13)

    ktls_crypto_info_t crypto_info;

    BIO *bio;

#endif

    if (which & SSL3_CC_READ) {

        if (s->enc_read_ctx != NULL) {

            EVP_CIPHER_CTX_reset(s->enc_read_ctx);

        } else {

            s->enc_read_ctx = EVP_CIPHER_CTX_new();

            if (s->enc_read_ctx == NULL) {

                SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);

                goto err;

            }

        }

        ciph_ctx = s->enc_read_ctx;

        iv = s->read_iv;

        RECORD_LAYER_reset_read_sequence(&s->rlayer);

    } else {

        s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;

        if (s->enc_write_ctx != NULL) {

            EVP_CIPHER_CTX_reset(s->enc_write_ctx);

        } else {

            s->enc_write_ctx = EVP_CIPHER_CTX_new();

            if (s->enc_write_ctx == NULL) {

                SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);

                goto err;

            }

        }

        ciph_ctx = s->enc_write_ctx;

        iv = s->write_iv;

        RECORD_LAYER_reset_write_sequence(&s->rlayer);

    }

    if (((which & SSL3_CC_CLIENT) && (which & SSL3_CC_WRITE))

            || ((which & SSL3_CC_SERVER) && (which & SSL3_CC_READ))) {

        if (which & SSL3_CC_EARLY) {

            EVP_MD_CTX *mdctx = NULL;

            long handlen;

            void *hdata;

            unsigned int hashlenui;

            const SSL_CIPHER *sslcipher = SSL_SESSION_get0_cipher(s->session);

            insecret = s->early_secret;

            label = client_early_traffic;

            labellen = sizeof(client_early_traffic) - 1;

            log_label = CLIENT_EARLY_LABEL;

            handlen = BIO_get_mem_data(s->s3.handshake_buffer, &hdata);

            if (handlen <= 0) {

                SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_HANDSHAKE_LENGTH);

                goto err;

            }

            if (s->early_data_state == SSL_EARLY_DATA_CONNECTING

                    && s->max_early_data > 0

                    && s->session->ext.max_early_data == 0) {

                /*

                 * If we are attempting to send early data, and we've decided to

                 * actually do it but max_early_data in s->session is 0 then we

                 * must be using an external PSK.

                 */

                if (!ossl_assert(s->psksession != NULL

                        && s->max_early_data ==

                           s->psksession->ext.max_early_data)) {

                    SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);

                    goto err;

                }

                sslcipher = SSL_SESSION_get0_cipher(s->psksession);

            }

            if (sslcipher == NULL) {

                SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_PSK);

                goto err;

            }

            /*

             * We need to calculate the handshake digest using the digest from

             * the session. We haven't yet selected our ciphersuite so we can't

             * use ssl_handshake_md().

             */

            mdctx = EVP_MD_CTX_new();

            if (mdctx == NULL) {

                SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);

                goto err;

            }

            /*

             * This ups the ref count on cipher so we better make sure we free

             * it again

             */

            if (!ssl_cipher_get_evp_cipher(s->ctx, sslcipher, &cipher)) {

                /* Error is already recorded */

                SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR);

                EVP_MD_CTX_free(mdctx);

                goto err;

            }

            md = ssl_md(s->ctx, sslcipher->algorithm2);

            if (md == NULL || !EVP_DigestInit_ex(mdctx, md, NULL)

                    || !EVP_DigestUpdate(mdctx, hdata, handlen)

                    || !EVP_DigestFinal_ex(mdctx, hashval, &hashlenui)) {

                SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);

                EVP_MD_CTX_free(mdctx);

                goto err;

            }

            hashlen = hashlenui;

            EVP_MD_CTX_free(mdctx);

            if (!tls13_hkdf_expand(s, md, insecret,

                                   early_exporter_master_secret,

                                   sizeof(early_exporter_master_secret) - 1,

                                   hashval, hashlen,

                                   s->early_exporter_master_secret, hashlen,

                                   1)) {

                SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);

                goto err;

            }

            if (!ssl_log_secret(s, EARLY_EXPORTER_SECRET_LABEL,

                                s->early_exporter_master_secret, hashlen)) {

                /* SSLfatal() already called */

                goto err;

            }

        } else if (which & SSL3_CC_HANDSHAKE) {

            insecret = s->handshake_secret;

            finsecret = s->client_finished_secret;

            finsecretlen = EVP_MD_get_size(ssl_handshake_md(s));

            label = client_handshake_traffic;

            labellen = sizeof(client_handshake_traffic) - 1;

            log_label = CLIENT_HANDSHAKE_LABEL;

            /*

             * The handshake hash used for the server read/client write handshake

             * traffic secret is the same as the hash for the server

             * write/client read handshake traffic secret. However, if we

             * processed early data then we delay changing the server

             * read/client write cipher state until later, and the handshake

             * hashes have moved on. Therefore we use the value saved earlier

             * when we did the server write/client read change cipher state.

             */

            hash = s->handshake_traffic_hash;

        } else {

            insecret = s->master_secret;

            label = client_application_traffic;

            labellen = sizeof(client_application_traffic) - 1;

            log_label = CLIENT_APPLICATION_LABEL;

            /*

             * For this we only use the handshake hashes up until the server

             * Finished hash. We do not include the client's Finished, which is

             * what ssl_handshake_hash() would give us. Instead we use the

             * previously saved value.

             */

            hash = s->server_finished_hash;

        }

    } else {

        /* Early data never applies to client-read/server-write */

        if (which & SSL3_CC_HANDSHAKE) {

            insecret = s->handshake_secret;

            finsecret = s->server_finished_secret;

            finsecretlen = EVP_MD_get_size(ssl_handshake_md(s));

            label = server_handshake_traffic;

            labellen = sizeof(server_handshake_traffic) - 1;

            log_label = SERVER_HANDSHAKE_LABEL;

        } else {

            insecret = s->master_secret;

            label = server_application_traffic;

            labellen = sizeof(server_application_traffic) - 1;

            log_label = SERVER_APPLICATION_LABEL;

        }

    }

    if (!(which & SSL3_CC_EARLY)) {

        md = ssl_handshake_md(s);

        cipher = s->s3.tmp.new_sym_enc;

        if (!ssl3_digest_cached_records(s, 1)

                || !ssl_handshake_hash(s, hashval, sizeof(hashval), &hashlen)) {

            /* SSLfatal() already called */;

            goto err;

        }

    }

    /*

     * Save the hash of handshakes up to now for use when we calculate the

     * client application traffic secret

     */

    if (label == server_application_traffic)

        memcpy(s->server_finished_hash, hashval, hashlen);

    if (label == server_handshake_traffic)

        memcpy(s->handshake_traffic_hash, hashval, hashlen);

    if (label == client_application_traffic) {

        /*

         * We also create the resumption master secret, but this time use the

         * hash for the whole handshake including the Client Finished

         */

        if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret,

                               resumption_master_secret,

                               sizeof(resumption_master_secret) - 1,

                               hashval, hashlen, s->resumption_master_secret,

                               hashlen, 1)) {

            /* SSLfatal() already called */

            goto err;

        }

    }

    /* check whether cipher is known */

    if(!ossl_assert(cipher != NULL))

        goto err;

    if (!derive_secret_key_and_iv(s, which & SSL3_CC_WRITE, md, cipher,

                                  insecret, hash, label, labellen, secret, key,

                                  iv, ciph_ctx)) {

        /* SSLfatal() already called */

        goto err;

    }

    if (label == server_application_traffic) {

        memcpy(s->server_app_traffic_secret, secret, hashlen);

        /* Now we create the exporter master secret */

        if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret,

                               exporter_master_secret,

                               sizeof(exporter_master_secret) - 1,

                               hash, hashlen, s->exporter_master_secret,

                               hashlen, 1)) {

            /* SSLfatal() already called */

            goto err;

        }

        if (!ssl_log_secret(s, EXPORTER_SECRET_LABEL, s->exporter_master_secret,

                            hashlen)) {

            /* SSLfatal() already called */

            goto err;

        }

    } else if (label == client_application_traffic)

        memcpy(s->client_app_traffic_secret, secret, hashlen);

    if (!ssl_log_secret(s, log_label, secret, hashlen)) {

        /* SSLfatal() already called */

        goto err;

    }

    if (finsecret != NULL

            && !tls13_derive_finishedkey(s, ssl_handshake_md(s), secret,

                                         finsecret, finsecretlen)) {

        /* SSLfatal() already called */

        goto err;

    }

    if (!s->server && label == client_early_traffic)

        s->statem.enc_write_state = ENC_WRITE_STATE_WRITE_PLAIN_ALERTS;

    else

        s->statem.enc_write_state = ENC_WRITE_STATE_VALID;

#ifndef OPENSSL_NO_KTLS

# if defined(OPENSSL_KTLS_TLS13)

    if (!(which & SSL3_CC_WRITE)

            || !(which & SSL3_CC_APPLICATION)

            || (s->options & SSL_OP_ENABLE_KTLS) == 0)

        goto skip_ktls;

    /* ktls supports only the maximum fragment size */

    if (ssl_get_max_send_fragment(s) != SSL3_RT_MAX_PLAIN_LENGTH)

        goto skip_ktls;

    /* ktls does not support record padding */

    if (s->record_padding_cb != NULL)

        goto skip_ktls;

    /* check that cipher is supported */

    if (!ktls_check_supported_cipher(s, cipher, ciph_ctx))

        goto skip_ktls;

    bio = s->wbio;

    if (!ossl_assert(bio != NULL)) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);

        goto err;

    }

    /* All future data will get encrypted by ktls. Flush the BIO or skip ktls */

    if (BIO_flush(bio) <= 0)

        goto skip_ktls;

    /* configure kernel crypto structure */

    if (!ktls_configure_crypto(s, cipher, ciph_ctx,

                               RECORD_LAYER_get_write_sequence(&s->rlayer),

                               &crypto_info, NULL, iv, key, NULL, 0))

        goto skip_ktls;

    /* ktls works with user provided buffers directly */

    if (BIO_set_ktls(bio, &crypto_info, which & SSL3_CC_WRITE))

        ssl3_release_write_buffer(s);

skip_ktls:

# endif

#endif

    ret = 1;

 err:

    if ((which & SSL3_CC_EARLY) != 0) {

        /* We up-refed this so now we need to down ref */

        ssl_evp_cipher_free(cipher);

    }

    OPENSSL_cleanse(key, sizeof(key));

    OPENSSL_cleanse(secret, sizeof(secret));

    return ret;

}

int tls13_update_key(SSL *s, int sending)

{

#ifdef CHARSET_EBCDIC

  static const unsigned char application_traffic[] = { 0x74, 0x72 ,0x61 ,0x66 ,0x66 ,0x69 ,0x63 ,0x20 ,0x75 ,0x70 ,0x64, 0x00};

#else

  static const unsigned char application_traffic[] = "traffic upd";

#endif

    const EVP_MD *md = ssl_handshake_md(s);

    size_t hashlen;

    unsigned char key[EVP_MAX_KEY_LENGTH];

    unsigned char *insecret, *iv;

    unsigned char secret[EVP_MAX_MD_SIZE];

    char *log_label;

    EVP_CIPHER_CTX *ciph_ctx;

    int ret = 0, l;

    if ((l = EVP_MD_get_size(md)) <= 0) {

        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);

        return 0;

    }

    hashlen = (size_t)l;

    if (s->server == sending)

        insecret = s->server_app_traffic_secret;

    else

        insecret = s->client_app_traffic_secret;

    if (sending) {

        s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;

        iv = s->write_iv;

        ciph_ctx = s->enc_write_ctx;

        RECORD_LAYER_reset_write_sequence(&s->rlayer);

    } else {

        iv = s->read_iv;

        ciph_ctx = s->enc_read_ctx;

        RECORD_LAYER_reset_read_sequence(&s->rlayer);

    }

    if (!derive_secret_key_and_iv(s, sending, md,

                                  s->s3.tmp.new_sym_enc, insecret, NULL,

                                  application_traffic,

                                  sizeof(application_traffic) - 1, secret, key,

                                  iv, ciph_ctx)) {

        /* SSLfatal() already called */

        goto err;

    }

    memcpy(insecret, secret, hashlen);

    /* Call Key log on successful traffic secret update */

    log_label = s->server == sending ? SERVER_APPLICATION_N_LABEL : CLIENT_APPLICATION_N_LABEL;

    if (!ssl_log_secret(s, log_label, secret, hashlen)) {

        /* SSLfatal() already called */

        goto err;

    }

    s->statem.enc_write_state = ENC_WRITE_STATE_VALID;

    ret = 1;

 err:

    OPENSSL_cleanse(key, sizeof(key));

    OPENSSL_cleanse(secret, sizeof(secret));

    return ret;

}

int tls13_alert_code(int code)

{

    /* There are 2 additional alerts in TLSv1.3 compared to TLSv1.2 */

    if (code == SSL_AD_MISSING_EXTENSION || code == SSL_AD_CERTIFICATE_REQUIRED)

        return code;

    return tls1_alert_code(code);

}

int tls13_export_keying_material(SSL *s, unsigned char *out, size_t olen,

                                 const char *label, size_t llen,

                                 const unsigned char *context,

                                 size_t contextlen, int use_context)

{

    unsigned char exportsecret[EVP_MAX_MD_SIZE];

#ifdef CHARSET_EBCDIC

    static const unsigned char exporterlabel[] = {0x65, 0x78, 0x70, 0x6F, 0x72, 0x74, 0x65, 0x72, 0x00};

#else

    static const unsigned char exporterlabel[] = "exporter";

#endif

    unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE];

    const EVP_MD *md = ssl_handshake_md(s);

    EVP_MD_CTX *ctx = EVP_MD_CTX_new();

    unsigned int hashsize, datalen;

    int ret = 0;

    if (ctx == NULL || md == NULL || !ossl_statem_export_allowed(s))

        goto err;

    if (!use_context)

        contextlen = 0;

    if (EVP_DigestInit_ex(ctx, md, NULL) <= 0

            || EVP_DigestUpdate(ctx, context, contextlen) <= 0

            || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0

            || EVP_DigestInit_ex(ctx, md, NULL) <= 0

            || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0

            || !tls13_hkdf_expand(s, md, s->exporter_master_secret,

                                  (const unsigned char *)label, llen,

                                  data, datalen, exportsecret, hashsize, 0)

            || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel,

                                  sizeof(exporterlabel) - 1, hash, hashsize,

                                  out, olen, 0))

        goto err;

    ret = 1;

 err:

    EVP_MD_CTX_free(ctx);

    return ret;

}

int tls13_export_keying_material_early(SSL *s, unsigned char *out, size_t olen,

                                       const char *label, size_t llen,

                                       const unsigned char *context,

                                       size_t contextlen)

{

#ifdef CHARSET_EBCDIC

  static const unsigned char exporterlabel[] = {0x65, 0x78, 0x70, 0x6F, 0x72, 0x74, 0x65, 0x72, 0x00};

#else

  static const unsigned char exporterlabel[] = "exporter";

#endif

    unsigned char exportsecret[EVP_MAX_MD_SIZE];

    unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE];

    const EVP_MD *md;

    EVP_MD_CTX *ctx = EVP_MD_CTX_new();

    unsigned int hashsize, datalen;

    int ret = 0;

    const SSL_CIPHER *sslcipher;

    if (ctx == NULL || !ossl_statem_export_early_allowed(s))

        goto err;

    if (!s->server && s->max_early_data > 0

            && s->session->ext.max_early_data == 0)

        sslcipher = SSL_SESSION_get0_cipher(s->psksession);

    else

        sslcipher = SSL_SESSION_get0_cipher(s->session);

    md = ssl_md(s->ctx, sslcipher->algorithm2);

    /*

     * Calculate the hash value and store it in |data|. The reason why

     * the empty string is used is that the definition of TLS-Exporter

     * is like so:

     *

     * TLS-Exporter(label, context_value, key_length) =

     *     HKDF-Expand-Label(Derive-Secret(Secret, label, ""),

     *                       "exporter", Hash(context_value), key_length)

     *

     * Derive-Secret(Secret, Label, Messages) =

     *       HKDF-Expand-Label(Secret, Label,

     *                         Transcript-Hash(Messages), Hash.length)

     *

     * Here Transcript-Hash is the cipher suite hash algorithm.

     */

    if (md == NULL

            || EVP_DigestInit_ex(ctx, md, NULL) <= 0

            || EVP_DigestUpdate(ctx, context, contextlen) <= 0

            || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0

            || EVP_DigestInit_ex(ctx, md, NULL) <= 0

            || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0

            || !tls13_hkdf_expand(s, md, s->early_exporter_master_secret,

                                  (const unsigned char *)label, llen,

                                  data, datalen, exportsecret, hashsize, 0)

            || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel,

                                  sizeof(exporterlabel) - 1, hash, hashsize,

                                  out, olen, 0))

        goto err;

    ret = 1;

 err:

    EVP_MD_CTX_free(ctx);

    return ret;

}