Example #1
0
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)
{
    static const unsigned char exporterlabel[] = "exporter";
    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(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 (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;
}
Example #2
0
int tls13_change_cipher_state(SSL *s, int which)
{
    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";
    unsigned char *iv;
    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 (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,
                         SSL_F_TLS13_CHANGE_CIPHER_STATE, 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,
                         SSL_F_TLS13_CHANGE_CIPHER_STATE, 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_F_TLS13_CHANGE_CIPHER_STATE,
                         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,
                             SSL_F_TLS13_CHANGE_CIPHER_STATE,
                             ERR_R_INTERNAL_ERROR);
                    goto err;
                }
                sslcipher = SSL_SESSION_get0_cipher(s->psksession);
            }
            if (sslcipher == NULL) {
                SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                         SSL_F_TLS13_CHANGE_CIPHER_STATE, 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,
                         SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE);
                goto err;
            }
            cipher = EVP_get_cipherbynid(SSL_CIPHER_get_cipher_nid(sslcipher));
            md = ssl_md(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,
                         SSL_F_TLS13_CHANGE_CIPHER_STATE, 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,
                         SSL_F_TLS13_CHANGE_CIPHER_STATE, 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_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_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;
        }
    }

    if (!derive_secret_key_and_iv(s, which & SSL3_CC_WRITE, md, cipher,
                                  insecret, hash, label, labellen, secret, 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;
    ret = 1;
 err:
    OPENSSL_cleanse(secret, sizeof(secret));
    return ret;
}
Example #3
0
/*
 * Construct the pre_shared_key extension
 */
int tls_construct_ctos_psk(SSL *s, WPACKET *pkt, unsigned int context, X509 *x,
                           size_t chainidx, int *al)
{
#ifndef OPENSSL_NO_TLS1_3
    uint32_t now, agesec, agems;
    size_t hashsize, binderoffset, msglen;
    unsigned char *binder = NULL, *msgstart = NULL;
    const EVP_MD *md;
    int ret = 0;

    s->session->ext.tick_identity = TLSEXT_PSK_BAD_IDENTITY;

    /*
     * If this is an incompatible or new session then we have nothing to resume
     * so don't add this extension.
     */
    if (s->session->ssl_version != TLS1_3_VERSION
            || s->session->ext.ticklen == 0)
        return 1;

    if (s->session->cipher == NULL) {
        SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_PSK, ERR_R_INTERNAL_ERROR);
        goto err;
    }

    md = ssl_md(s->session->cipher->algorithm2);
    if (md == NULL) {
        /* Don't recognise this cipher so we can't use the session. Ignore it */
        return 1;
    }

    /*
     * Technically the C standard just says time() returns a time_t and says
     * nothing about the encoding of that type. In practice most implementations
     * follow POSIX which holds it as an integral type in seconds since epoch.
     * We've already made the assumption that we can do this in multiple places
     * in the code, so portability shouldn't be an issue.
     */
    now = (uint32_t)time(NULL);
    agesec = now - (uint32_t)s->session->time;

    if (s->session->ext.tick_lifetime_hint < agesec) {
        /* Ticket is too old. Ignore it. */
        return 1;
    }

    /*
     * Calculate age in ms. We're just doing it to nearest second. Should be
     * good enough.
     */
    agems = agesec * (uint32_t)1000;

    if (agesec != 0 && agems / (uint32_t)1000 != agesec) {
        /*
         * Overflow. Shouldn't happen unless this is a *really* old session. If
         * so we just ignore it.
         */
        return 1;
    }

    /*
     * Obfuscate the age. Overflow here is fine, this addition is supposed to
     * be mod 2^32.
     */
    agems += s->session->ext.tick_age_add;

    hashsize = EVP_MD_size(md);

    /* Create the extension, but skip over the binder for now */
    if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_psk)
            || !WPACKET_start_sub_packet_u16(pkt)
            || !WPACKET_start_sub_packet_u16(pkt)
            || !WPACKET_sub_memcpy_u16(pkt, s->session->ext.tick,
                                       s->session->ext.ticklen)
            || !WPACKET_put_bytes_u32(pkt, agems)
            || !WPACKET_close(pkt)
            || !WPACKET_get_total_written(pkt, &binderoffset)
            || !WPACKET_start_sub_packet_u16(pkt)
            || !WPACKET_sub_allocate_bytes_u8(pkt, hashsize, &binder)
            || !WPACKET_close(pkt)
            || !WPACKET_close(pkt)
            || !WPACKET_get_total_written(pkt, &msglen)
               /*
                * We need to fill in all the sub-packet lengths now so we can
                * calculate the HMAC of the message up to the binders
                */
            || !WPACKET_fill_lengths(pkt)) {
        SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_PSK, ERR_R_INTERNAL_ERROR);
        goto err;
    }

    msgstart = WPACKET_get_curr(pkt) - msglen;

    if (tls_psk_do_binder(s, md, msgstart, binderoffset, NULL, binder,
                          s->session, 1) != 1) {
        SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_PSK, ERR_R_INTERNAL_ERROR);
        goto err;
    }

    s->session->ext.tick_identity = 0;

    ret = 1;
 err:
    return ret;
#else
    return 1;
#endif
}
Example #4
0
int tls_parse_ctos_psk(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
                       size_t chainidx, int *al)
{
    PACKET identities, binders, binder;
    size_t binderoffset, hashsize;
    SSL_SESSION *sess = NULL;
    unsigned int id, i, ext = 0;
    const EVP_MD *md = NULL;

    /*
     * If we have no PSK kex mode that we recognise then we can't resume so
     * ignore this extension
     */
    if ((s->ext.psk_kex_mode
            & (TLSEXT_KEX_MODE_FLAG_KE | TLSEXT_KEX_MODE_FLAG_KE_DHE)) == 0)
        return 1;

    if (!PACKET_get_length_prefixed_2(pkt, &identities)) {
        *al = SSL_AD_DECODE_ERROR;
        return 0;
    }

    for (id = 0; PACKET_remaining(&identities) != 0; id++) {
        PACKET identity;
        unsigned long ticket_agel;

        if (!PACKET_get_length_prefixed_2(&identities, &identity)
                || !PACKET_get_net_4(&identities, &ticket_agel)) {
            *al = SSL_AD_DECODE_ERROR;
            return 0;
        }

        if (s->psk_find_session_cb != NULL
                && !s->psk_find_session_cb(s, PACKET_data(&identity),
                                           PACKET_remaining(&identity),
                                           &sess)) {
            *al = SSL_AD_INTERNAL_ERROR;
            return 0;
        }

        if (sess != NULL) {
            /* We found a PSK */
            SSL_SESSION *sesstmp = ssl_session_dup(sess, 0);

            if (sesstmp == NULL) {
                *al = SSL_AD_INTERNAL_ERROR;
                return 0;
            }
            SSL_SESSION_free(sess);
            sess = sesstmp;

            /*
             * We've just been told to use this session for this context so
             * make sure the sid_ctx matches up.
             */
            memcpy(sess->sid_ctx, s->sid_ctx, s->sid_ctx_length);
            sess->sid_ctx_length = s->sid_ctx_length;
            ext = 1;
        } else {
            uint32_t ticket_age = 0, now, agesec, agems;
            int ret = tls_decrypt_ticket(s, PACKET_data(&identity),
                                         PACKET_remaining(&identity), NULL, 0,
                                         &sess);

            if (ret == TICKET_FATAL_ERR_MALLOC
                    || ret == TICKET_FATAL_ERR_OTHER) {
                *al = SSL_AD_INTERNAL_ERROR;
                return 0;
            }
            if (ret == TICKET_NO_DECRYPT)
                continue;

            ticket_age = (uint32_t)ticket_agel;
            now = (uint32_t)time(NULL);
            agesec = now - (uint32_t)sess->time;
            agems = agesec * (uint32_t)1000;
            ticket_age -= sess->ext.tick_age_add;

            /*
             * For simplicity we do our age calculations in seconds. If the
             * client does it in ms then it could appear that their ticket age
             * is longer than ours (our ticket age calculation should always be
             * slightly longer than the client's due to the network latency).
             * Therefore we add 1000ms to our age calculation to adjust for
             * rounding errors.
             */
            if (sess->timeout >= (long)agesec
                    && agems / (uint32_t)1000 == agesec
                    && ticket_age <= agems + 1000
                    && ticket_age + TICKET_AGE_ALLOWANCE >= agems + 1000) {
                /*
                 * Ticket age is within tolerance and not expired. We allow it
                 * for early data
                 */
                s->ext.early_data_ok = 1;
            }
        }

        md = ssl_md(sess->cipher->algorithm2);
        if (md != ssl_md(s->s3->tmp.new_cipher->algorithm2)) {
            /* The ciphersuite is not compatible with this session. */
            SSL_SESSION_free(sess);
            sess = NULL;
            continue;
        }
        break;
    }

    if (sess == NULL)
        return 1;

    binderoffset = PACKET_data(pkt) - (const unsigned char *)s->init_buf->data;
    hashsize = EVP_MD_size(md);

    if (!PACKET_get_length_prefixed_2(pkt, &binders)) {
        *al = SSL_AD_DECODE_ERROR;
        goto err;
    }

    for (i = 0; i <= id; i++) {
        if (!PACKET_get_length_prefixed_1(&binders, &binder)) {
            *al = SSL_AD_DECODE_ERROR;
            goto err;
        }
    }

    if (PACKET_remaining(&binder) != hashsize
            || tls_psk_do_binder(s, md,
                                 (const unsigned char *)s->init_buf->data,
                                 binderoffset, PACKET_data(&binder), NULL,
                                 sess, 0, ext) != 1) {
        *al = SSL_AD_DECODE_ERROR;
        SSLerr(SSL_F_TLS_PARSE_CTOS_PSK, ERR_R_INTERNAL_ERROR);
        goto err;
    }

    sess->ext.tick_identity = id;

    SSL_SESSION_free(s->session);
    s->session = sess;
    return 1;
err:
    SSL_SESSION_free(sess);
    return 0;
}
Example #5
0
int tls_parse_ctos_psk(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
                       size_t chainidx, int *al)
{
    PACKET identities, binders, binder;
    size_t binderoffset, hashsize;
    SSL_SESSION *sess = NULL;
    unsigned int id, i;
    const EVP_MD *md = NULL;
    uint32_t ticket_age = 0, now, agesec, agems;

    /*
     * If we have no PSK kex mode that we recognise then we can't resume so
     * ignore this extension
     */
    if ((s->ext.psk_kex_mode
            & (TLSEXT_KEX_MODE_FLAG_KE | TLSEXT_KEX_MODE_FLAG_KE_DHE)) == 0)
        return 1;

    if (!PACKET_get_length_prefixed_2(pkt, &identities)) {
        *al = SSL_AD_DECODE_ERROR;
        return 0;
    }

    for (id = 0; PACKET_remaining(&identities) != 0; id++) {
        PACKET identity;
        unsigned long ticket_agel;
        int ret;

        if (!PACKET_get_length_prefixed_2(&identities, &identity)
                || !PACKET_get_net_4(&identities, &ticket_agel)) {
            *al = SSL_AD_DECODE_ERROR;
            return 0;
        }

        ticket_age = (uint32_t)ticket_agel;

        ret = tls_decrypt_ticket(s, PACKET_data(&identity),
                                 PACKET_remaining(&identity), NULL, 0, &sess);
        if (ret == TICKET_FATAL_ERR_MALLOC || ret == TICKET_FATAL_ERR_OTHER) {
            *al = SSL_AD_INTERNAL_ERROR;
            return 0;
        }
        if (ret == TICKET_NO_DECRYPT)
            continue;

        md = ssl_md(sess->cipher->algorithm2);
        if (md == NULL) {
            /*
             * Don't recognise this cipher so we can't use the session.
             * Ignore it
             */
            SSL_SESSION_free(sess);
            sess = NULL;
            continue;
        }

        /*
         * TODO(TLS1.3): Somehow we need to handle the case of a ticket renewal.
         * Ignored for now
         */

        break;
    }

    if (sess == NULL)
        return 1;

    binderoffset = PACKET_data(pkt) - (const unsigned char *)s->init_buf->data;
    hashsize = EVP_MD_size(md);

    if (!PACKET_get_length_prefixed_2(pkt, &binders)) {
        *al = SSL_AD_DECODE_ERROR;
        goto err;
    }

    for (i = 0; i <= id; i++) {
        if (!PACKET_get_length_prefixed_1(&binders, &binder)) {
            *al = SSL_AD_DECODE_ERROR;
            goto err;
        }
    }

    if (PACKET_remaining(&binder) != hashsize
            || tls_psk_do_binder(s, md,
                                 (const unsigned char *)s->init_buf->data,
                                 binderoffset, PACKET_data(&binder), NULL,
                                 sess, 0) != 1) {
        *al = SSL_AD_DECODE_ERROR;
        SSLerr(SSL_F_TLS_PARSE_CTOS_PSK, ERR_R_INTERNAL_ERROR);
        goto err;
    }

    sess->ext.tick_identity = id;

    now = (uint32_t)time(NULL);
    agesec = now - (uint32_t)sess->time;
    agems = agesec * (uint32_t)1000;
    ticket_age -= sess->ext.tick_age_add;


    /*
     * For simplicity we do our age calculations in seconds. If the client does
     * it in ms then it could appear that their ticket age is longer than ours
     * (our ticket age calculation should always be slightly longer than the
     * client's due to the network latency). Therefore we add 1000ms to our age
     * calculation to adjust for rounding errors.
     */
    if (sess->timeout >= (long)agesec
            && agems / (uint32_t)1000 == agesec
            && ticket_age <= agems + 1000
            && ticket_age + TICKET_AGE_ALLOWANCE >= agems + 1000) {
        /*
         * Ticket age is within tolerance and not expired. We allow it for early
         * data
         */
        s->ext.early_data_ok = 1;
    }


    SSL_SESSION_free(s->session);
    s->session = sess;
    return 1;
err:
    SSL_SESSION_free(sess);
    return 0;
}