/* $OpenBSD: s_cb.c,v 1.22 2025/01/02 13:10:03 tb Exp $ */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young (eay@cryptsoft.com).
 * The implementation was written so as to conform with Netscapes SSL.
 *
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
 *
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young (eay@cryptsoft.com)"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
 *
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */
/* ====================================================================
 * Copyright (c) 1998-2006 The OpenSSL Project.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    openssl-core@openssl.org.
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * ====================================================================
 *
 * This product includes cryptographic software written by Eric Young
 * (eay@cryptsoft.com).  This product includes software written by Tim
 * Hudson (tjh@cryptsoft.com).
 *
 */

#include <sys/socket.h>

#include <netinet/in.h>

#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "apps.h"

#include <openssl/err.h>
#include <openssl/ssl.h>
#include <openssl/x509.h>

#define COOKIE_SECRET_LENGTH    16

int verify_depth = 0;
int verify_return_error = 0;
unsigned char cookie_secret[COOKIE_SECRET_LENGTH];
int cookie_initialized = 0;

int
verify_callback(int ok, X509_STORE_CTX * ctx)
{
        X509 *err_cert;
        int err, depth;

        err_cert = X509_STORE_CTX_get_current_cert(ctx);
        err = X509_STORE_CTX_get_error(ctx);
        depth = X509_STORE_CTX_get_error_depth(ctx);

        BIO_printf(bio_err, "depth=%d ", depth);
        if (err_cert) {
                X509_NAME_print_ex(bio_err, X509_get_subject_name(err_cert),
                    0, XN_FLAG_ONELINE);
                BIO_puts(bio_err, "\n");
        } else
                BIO_puts(bio_err, "<no cert>\n");
        if (!ok) {
                BIO_printf(bio_err, "verify error:num=%d:%s\n", err,
                    X509_verify_cert_error_string(err));
                if (verify_depth >= depth) {
                        if (!verify_return_error)
                                ok = 1;
                } else {
                        ok = 0;
                }
        }
        switch (err) {
        case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT:
                BIO_puts(bio_err, "issuer= ");
                if (err_cert == NULL)
                        BIO_puts(bio_err, "<error getting cert>");
                else
                        X509_NAME_print_ex(bio_err,
                            X509_get_issuer_name(err_cert), 0, XN_FLAG_ONELINE);
                BIO_puts(bio_err, "\n");
                break;
        case X509_V_ERR_CERT_NOT_YET_VALID:
        case X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD:
                BIO_printf(bio_err, "notBefore=");
                if (err_cert == NULL)
                        BIO_printf(bio_err, " <error getting cert>");
                else
                        ASN1_TIME_print(bio_err, X509_get_notBefore(err_cert));
                BIO_printf(bio_err, "\n");
                break;
        case X509_V_ERR_CERT_HAS_EXPIRED:
        case X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD:
                BIO_printf(bio_err, "notAfter=");
                if (err_cert == NULL)
                        BIO_printf(bio_err, " <error getting cert>");
                else
                        ASN1_TIME_print(bio_err, X509_get_notAfter(err_cert));
                BIO_printf(bio_err, "\n");
                break;
        case X509_V_ERR_NO_EXPLICIT_POLICY:
                break;
        }

        BIO_printf(bio_err, "verify return:%d\n", ok);
        return (ok);
}

int
set_cert_stuff(SSL_CTX * ctx, char *cert_file, char *key_file)
{
        if (cert_file == NULL)
                return 1;

        if (key_file == NULL)
                key_file = cert_file;

        if (SSL_CTX_use_certificate_file(ctx, cert_file, SSL_FILETYPE_PEM) <= 0) {
                BIO_printf(bio_err,
                    "unable to get certificate from '%s'\n", cert_file);
                ERR_print_errors(bio_err);
                return 0;
        }
        if (SSL_CTX_use_PrivateKey_file(ctx, key_file, SSL_FILETYPE_PEM) <= 0) {
                BIO_printf(bio_err, "unable to get private key from '%s'\n",
                    key_file);
                ERR_print_errors(bio_err);
                return 0;
        }

        /* Now we know that a key and cert have been set against the context. */
        if (!SSL_CTX_check_private_key(ctx)) {
                BIO_printf(bio_err,
                    "Private key does not match the certificate public key\n");
                return 0;
        }

        return 1;
}

int
set_cert_key_stuff(SSL_CTX * ctx, X509 * cert, EVP_PKEY * key)
{
        if (cert == NULL)
                return 1;
        if (SSL_CTX_use_certificate(ctx, cert) <= 0) {
                BIO_printf(bio_err, "error setting certificate\n");
                ERR_print_errors(bio_err);
                return 0;
        }
        if (SSL_CTX_use_PrivateKey(ctx, key) <= 0) {
                BIO_printf(bio_err, "error setting private key\n");
                ERR_print_errors(bio_err);
                return 0;
        }
        /*
         * Now we know that a key and cert have been set against the SSL
         * context
         */
        if (!SSL_CTX_check_private_key(ctx)) {
                BIO_printf(bio_err,
                    "Private key does not match the certificate public key\n");
                return 0;
        }
        return 1;
}

int
ssl_print_tmp_key(BIO *out, SSL *s)
{
        const char *cname;
        EVP_PKEY *pkey;
        EC_KEY *ec;
        const EC_GROUP *group;
        int nid;

        if (!SSL_get_server_tmp_key(s, &pkey))
                return 0;

        BIO_puts(out, "Server Temp Key: ");
        switch (EVP_PKEY_id(pkey)) {
        case EVP_PKEY_DH:
                BIO_printf(out, "DH, %d bits\n", EVP_PKEY_bits(pkey));
                break;

        case EVP_PKEY_EC:
                if ((ec = EVP_PKEY_get0_EC_KEY(pkey)) == NULL)
                        goto err;
                if ((group = EC_KEY_get0_group(ec)) == NULL)
                        goto err;

                nid = EC_GROUP_get_curve_name(group);

                if ((cname = EC_curve_nid2nist(nid)) == NULL)
                        cname = OBJ_nid2sn(nid);

                BIO_printf(out, "ECDH, %s, %d bits\n", cname, EVP_PKEY_bits(pkey));
                break;

        default:
                BIO_printf(out, "%s, %d bits\n", OBJ_nid2sn(EVP_PKEY_id(pkey)),
                    EVP_PKEY_bits(pkey));
        }

 err:
        EVP_PKEY_free(pkey);
        return 1;
}

long
bio_dump_callback(BIO * bio, int cmd, const char *argp,
    int argi, long argl, long ret)
{
        BIO *out;

        out = (BIO *) BIO_get_callback_arg(bio);
        if (out == NULL)
                return (ret);

        if (cmd == (BIO_CB_READ | BIO_CB_RETURN)) {
                BIO_printf(out,
                    "read from %p [%p] (%lu bytes => %ld (0x%lX))\n",
                    (void *) bio, argp, (unsigned long) argi, ret, ret);
                BIO_dump(out, argp, (int) ret);
                return (ret);
        } else if (cmd == (BIO_CB_WRITE | BIO_CB_RETURN)) {
                BIO_printf(out,
                    "write to %p [%p] (%lu bytes => %ld (0x%lX))\n",
                    (void *) bio, argp, (unsigned long) argi, ret, ret);
                BIO_dump(out, argp, (int) ret);
        }
        return (ret);
}

void
apps_ssl_info_callback(const SSL * s, int where, int ret)
{
        const char *str;
        int w;

        w = where & ~SSL_ST_MASK;

        if (w & SSL_ST_CONNECT)
                str = "SSL_connect";
        else if (w & SSL_ST_ACCEPT)
                str = "SSL_accept";
        else
                str = "undefined";

        if (where & SSL_CB_LOOP) {
                BIO_printf(bio_err, "%s:%s\n", str, SSL_state_string_long(s));
        } else if (where & SSL_CB_ALERT) {
                str = (where & SSL_CB_READ) ? "read" : "write";
                BIO_printf(bio_err, "SSL3 alert %s:%s:%s\n", str,
                    SSL_alert_type_string_long(ret),
                    SSL_alert_desc_string_long(ret));
        } else if (where & SSL_CB_EXIT) {
                if (ret == 0)
                        BIO_printf(bio_err, "%s:failed in %s\n",
                            str, SSL_state_string_long(s));
                else if (ret < 0) {
                        BIO_printf(bio_err, "%s:error in %s\n",
                            str, SSL_state_string_long(s));
                }
        }
}


void
msg_cb(int write_p, int version, int content_type, const void *buf, size_t len, SSL * ssl, void *arg)
{
        BIO *bio = arg;
        const char *str_write_p, *str_version, *str_content_type = "",
            *str_details1 = "", *str_details2 = "";

        str_write_p = write_p ? ">>>" : "<<<";

        /* XXX convert to using ssl_get_version */
        switch (version) {
        case SSL2_VERSION:
                str_version = "SSL 2.0";
                break;
        case SSL3_VERSION:
                str_version = "SSL 3.0 ";
                break;
        case TLS1_VERSION:
                str_version = "TLS 1.0 ";
                break;
        case TLS1_1_VERSION:
                str_version = "TLS 1.1 ";
                break;
        case TLS1_2_VERSION:
                str_version = "TLS 1.2 ";
                break;
        case TLS1_3_VERSION:
                str_version = "TLS 1.3 ";
                break;
        case DTLS1_VERSION:
                str_version = "DTLS 1.0 ";
                break;
        case DTLS1_2_VERSION:
                str_version = "DTLS 1.2 ";
                break;
        default:
                str_version = "???";
        }

        if (version == SSL2_VERSION) {
                str_details1 = "???";

                if (len > 0) {
                        /* XXX magic numbers */
                        switch (((const unsigned char *) buf)[0]) {
                        case 0:
                                str_details1 = ", ERROR:";
                                str_details2 = " ???";
                                if (len >= 3) {
                                        unsigned err = (((const unsigned char *) buf)[1] << 8) + ((const unsigned char *) buf)[2];

                                        switch (err) {
                                        case 0x0001:
                                                str_details2 = " NO-CIPHER-ERROR";
                                                break;
                                        case 0x0002:
                                                str_details2 = " NO-CERTIFICATE-ERROR";
                                                break;
                                        case 0x0004:
                                                str_details2 = " BAD-CERTIFICATE-ERROR";
                                                break;
                                        case 0x0006:
                                                str_details2 = " UNSUPPORTED-CERTIFICATE-TYPE-ERROR";
                                                break;
                                        }
                                }
                                break;
                        case 1:
                                str_details1 = ", CLIENT-HELLO";
                                break;
                        case 2:
                                str_details1 = ", CLIENT-MASTER-KEY";
                                break;
                        case 3:
                                str_details1 = ", CLIENT-FINISHED";
                                break;
                        case 4:
                                str_details1 = ", SERVER-HELLO";
                                break;
                        case 5:
                                str_details1 = ", SERVER-VERIFY";
                                break;
                        case 6:
                                str_details1 = ", SERVER-FINISHED";
                                break;
                        case 7:
                                str_details1 = ", REQUEST-CERTIFICATE";
                                break;
                        case 8:
                                str_details1 = ", CLIENT-CERTIFICATE";
                                break;
                        }
                }
        }
        if (version == SSL3_VERSION || version == TLS1_VERSION ||
            version == TLS1_1_VERSION || version == TLS1_2_VERSION ||
            version == TLS1_3_VERSION || version == DTLS1_VERSION ||
            version == DTLS1_2_VERSION) {
                /* XXX magic numbers are in ssl3.h */
                switch (content_type) {
                case 20:
                        str_content_type = "ChangeCipherSpec";
                        break;
                case 21:
                        str_content_type = "Alert";
                        break;
                case 22:
                        str_content_type = "Handshake";
                        break;
                }

                if (content_type == 21) {       /* Alert */
                        str_details1 = ", ???";

                        if (len == 2) {
                                switch (((const unsigned char *) buf)[0]) {
                                case 1:
                                        str_details1 = ", warning";
                                        break;
                                case 2:
                                        str_details1 = ", fatal";
                                        break;
                                }

                                str_details2 = " ???";
                                switch (((const unsigned char *) buf)[1]) {
                                case 0:
                                        str_details2 = " close_notify";
                                        break;
                                case 10:
                                        str_details2 = " unexpected_message";
                                        break;
                                case 20:
                                        str_details2 = " bad_record_mac";
                                        break;
                                case 21:
                                        str_details2 = " decryption_failed";
                                        break;
                                case 22:
                                        str_details2 = " record_overflow";
                                        break;
                                case 30:
                                        str_details2 = " decompression_failure";
                                        break;
                                case 40:
                                        str_details2 = " handshake_failure";
                                        break;
                                case 42:
                                        str_details2 = " bad_certificate";
                                        break;
                                case 43:
                                        str_details2 = " unsupported_certificate";
                                        break;
                                case 44:
                                        str_details2 = " certificate_revoked";
                                        break;
                                case 45:
                                        str_details2 = " certificate_expired";
                                        break;
                                case 46:
                                        str_details2 = " certificate_unknown";
                                        break;
                                case 47:
                                        str_details2 = " illegal_parameter";
                                        break;
                                case 48:
                                        str_details2 = " unknown_ca";
                                        break;
                                case 49:
                                        str_details2 = " access_denied";
                                        break;
                                case 50:
                                        str_details2 = " decode_error";
                                        break;
                                case 51:
                                        str_details2 = " decrypt_error";
                                        break;
                                case 60:
                                        str_details2 = " export_restriction";
                                        break;
                                case 70:
                                        str_details2 = " protocol_version";
                                        break;
                                case 71:
                                        str_details2 = " insufficient_security";
                                        break;
                                case 80:
                                        str_details2 = " internal_error";
                                        break;
                                case 90:
                                        str_details2 = " user_canceled";
                                        break;
                                case 100:
                                        str_details2 = " no_renegotiation";
                                        break;
                                case 110:
                                        str_details2 = " unsupported_extension";
                                        break;
                                case 111:
                                        str_details2 = " certificate_unobtainable";
                                        break;
                                case 112:
                                        str_details2 = " unrecognized_name";
                                        break;
                                case 113:
                                        str_details2 = " bad_certificate_status_response";
                                        break;
                                case 114:
                                        str_details2 = " bad_certificate_hash_value";
                                        break;
                                case 115:
                                        str_details2 = " unknown_psk_identity";
                                        break;
                                }
                        }
                }
                if (content_type == 22) {       /* Handshake */
                        str_details1 = "???";

                        if (len > 0) {
                                switch (((const unsigned char *) buf)[0]) {
                                case 0:
                                        str_details1 = ", HelloRequest";
                                        break;
                                case 1:
                                        str_details1 = ", ClientHello";
                                        break;
                                case 2:
                                        str_details1 = ", ServerHello";
                                        break;
                                case 3:
                                        str_details1 = ", HelloVerifyRequest";
                                        break;
                                case 4:
                                        str_details1 = ", NewSessionTicket";
                                        break;
                                case 5:
                                        str_details1 = ", EndOfEarlyData";
                                        break;
                                case 8:
                                        str_details1 = ", EncryptedExtensions";
                                        break;
                                case 11:
                                        str_details1 = ", Certificate";
                                        break;
                                case 12:
                                        str_details1 = ", ServerKeyExchange";
                                        break;
                                case 13:
                                        str_details1 = ", CertificateRequest";
                                        break;
                                case 14:
                                        str_details1 = ", ServerHelloDone";
                                        break;
                                case 15:
                                        str_details1 = ", CertificateVerify";
                                        break;
                                case 16:
                                        str_details1 = ", ClientKeyExchange";
                                        break;
                                case 20:
                                        str_details1 = ", Finished";
                                        break;
                                case 24:
                                        str_details1 = ", KeyUpdate";
                                        break;
                                }
                        }
                }
        }
        BIO_printf(bio, "%s %s%s [length %04lx]%s%s\n", str_write_p,
            str_version, str_content_type, (unsigned long) len,
            str_details1, str_details2);

        if (len > 0) {
                size_t num, i;

                BIO_printf(bio, "   ");
                num = len;

                for (i = 0; i < num; i++) {
                        if (i % 16 == 0 && i > 0)
                                BIO_printf(bio, "\n   ");
                        BIO_printf(bio, " %02x",
                            ((const unsigned char *) buf)[i]);
                }
                if (i < len)
                        BIO_printf(bio, " ...");
                BIO_printf(bio, "\n");
        }
        (void) BIO_flush(bio);
}

void
tlsext_cb(SSL * s, int client_server, int type, unsigned char *data, int len,
    void *arg)
{
        BIO *bio = arg;
        char *extname;

        switch (type) {
        case TLSEXT_TYPE_server_name:
                extname = "server name";
                break;

        case TLSEXT_TYPE_max_fragment_length:
                extname = "max fragment length";
                break;

        case TLSEXT_TYPE_client_certificate_url:
                extname = "client certificate URL";
                break;

        case TLSEXT_TYPE_trusted_ca_keys:
                extname = "trusted CA keys";
                break;

        case TLSEXT_TYPE_truncated_hmac:
                extname = "truncated HMAC";
                break;

        case TLSEXT_TYPE_status_request:
                extname = "status request";
                break;

        case TLSEXT_TYPE_user_mapping:
                extname = "user mapping";
                break;

        case TLSEXT_TYPE_client_authz:
                extname = "client authz";
                break;

        case TLSEXT_TYPE_server_authz:
                extname = "server authz";
                break;

        case TLSEXT_TYPE_cert_type:
                extname = "cert type";
                break;

        case TLSEXT_TYPE_supported_groups:
                extname = "supported groups";
                break;

        case TLSEXT_TYPE_ec_point_formats:
                extname = "EC point formats";
                break;

        case TLSEXT_TYPE_srp:
                extname = "SRP";
                break;

        case TLSEXT_TYPE_signature_algorithms:
                extname = "signature algorithms";
                break;

        case TLSEXT_TYPE_use_srtp:
                extname = "use SRTP";
                break;

        case TLSEXT_TYPE_heartbeat:
                extname = "heartbeat";
                break;

        case TLSEXT_TYPE_application_layer_protocol_negotiation:
                extname = "application layer protocol negotiation";
                break;

        case TLSEXT_TYPE_padding:
                extname = "TLS padding";
                break;

        case TLSEXT_TYPE_session_ticket:
                extname = "session ticket";
                break;

#if defined(LIBRESSL_HAS_TLS1_3) || defined(LIBRESSL_INTERNAL)
        case TLSEXT_TYPE_pre_shared_key:
                extname = "pre shared key";
                break;

        case TLSEXT_TYPE_early_data:
                extname = "early data";
                break;

        case TLSEXT_TYPE_supported_versions:
                extname = "supported versions";
                break;

        case TLSEXT_TYPE_cookie:
                extname = "cookie";
                break;

        case TLSEXT_TYPE_psk_key_exchange_modes:
                extname = "PSK key exchange modes";
                break;

        case TLSEXT_TYPE_certificate_authorities:
                extname = "certificate authorities";
                break;

        case TLSEXT_TYPE_oid_filters:
                extname = "OID filters";
                break;

        case TLSEXT_TYPE_post_handshake_auth:
                extname = "post handshake auth";
                break;

        case TLSEXT_TYPE_signature_algorithms_cert:
                extname = "signature algorithms cert";
                break;

        case TLSEXT_TYPE_key_share:
                extname = "key share";
                break;
#endif

        case TLSEXT_TYPE_renegotiate:
                extname = "renegotiation info";
                break;

        default:
                extname = "unknown";
                break;

        }

        BIO_printf(bio, "TLS %s extension \"%s\" (id=%d), len=%d\n",
            client_server ? "server" : "client", extname, type, len);
        BIO_dump(bio, (char *) data, len);
        (void) BIO_flush(bio);
}

int
generate_cookie_callback(SSL * ssl, unsigned char *cookie,
    unsigned int *cookie_len)
{
        unsigned char *buffer, result[EVP_MAX_MD_SIZE];
        unsigned int length, resultlength;
        union {
                struct sockaddr sa;
                struct sockaddr_in s4;
                struct sockaddr_in6 s6;
        } peer;

        /* Initialize a random secret */
        if (!cookie_initialized) {
                arc4random_buf(cookie_secret, COOKIE_SECRET_LENGTH);
                cookie_initialized = 1;
        }
        /* Read peer information */
        (void) BIO_dgram_get_peer(SSL_get_rbio(ssl), &peer);

        /* Create buffer with peer's address and port */
        length = 0;
        switch (peer.sa.sa_family) {
        case AF_INET:
                length += sizeof(struct in_addr);
                length += sizeof(peer.s4.sin_port);
                break;
        case AF_INET6:
                length += sizeof(struct in6_addr);
                length += sizeof(peer.s6.sin6_port);
                break;
        default:
                OPENSSL_assert(0);
                break;
        }
        buffer = malloc(length);

        if (buffer == NULL) {
                BIO_printf(bio_err, "out of memory\n");
                return 0;
        }
        switch (peer.sa.sa_family) {
        case AF_INET:
                memcpy(buffer, &peer.s4.sin_port, sizeof(peer.s4.sin_port));
                memcpy(buffer + sizeof(peer.s4.sin_port),
                    &peer.s4.sin_addr, sizeof(struct in_addr));
                break;
        case AF_INET6:
                memcpy(buffer, &peer.s6.sin6_port, sizeof(peer.s6.sin6_port));
                memcpy(buffer + sizeof(peer.s6.sin6_port),
                    &peer.s6.sin6_addr, sizeof(struct in6_addr));
                break;
        default:
                OPENSSL_assert(0);
                break;
        }

        /* Calculate HMAC of buffer using the secret */
        HMAC(EVP_sha1(), cookie_secret, COOKIE_SECRET_LENGTH,
            buffer, length, result, &resultlength);
        free(buffer);

        memcpy(cookie, result, resultlength);
        *cookie_len = resultlength;

        return 1;
}

int
verify_cookie_callback(SSL * ssl, const unsigned char *cookie,
    unsigned int cookie_len)
{
        unsigned char *buffer, result[EVP_MAX_MD_SIZE];
        unsigned int length, resultlength;
        union {
                struct sockaddr sa;
                struct sockaddr_in s4;
                struct sockaddr_in6 s6;
        } peer;

        /* If secret isn't initialized yet, the cookie can't be valid */
        if (!cookie_initialized)
                return 0;

        /* Read peer information */
        (void) BIO_dgram_get_peer(SSL_get_rbio(ssl), &peer);

        /* Create buffer with peer's address and port */
        length = 0;
        switch (peer.sa.sa_family) {
        case AF_INET:
                length += sizeof(struct in_addr);
                length += sizeof(peer.s4.sin_port);
                break;
        case AF_INET6:
                length += sizeof(struct in6_addr);
                length += sizeof(peer.s6.sin6_port);
                break;
        default:
                OPENSSL_assert(0);
                break;
        }
        buffer = malloc(length);

        if (buffer == NULL) {
                BIO_printf(bio_err, "out of memory\n");
                return 0;
        }
        switch (peer.sa.sa_family) {
        case AF_INET:
                memcpy(buffer, &peer.s4.sin_port, sizeof(peer.s4.sin_port));
                memcpy(buffer + sizeof(peer.s4.sin_port),
                    &peer.s4.sin_addr, sizeof(struct in_addr));
                break;
        case AF_INET6:
                memcpy(buffer, &peer.s6.sin6_port, sizeof(peer.s6.sin6_port));
                memcpy(buffer + sizeof(peer.s6.sin6_port),
                    &peer.s6.sin6_addr, sizeof(struct in6_addr));
                break;
        default:
                OPENSSL_assert(0);
                break;
        }

        /* Calculate HMAC of buffer using the secret */
        if (HMAC(EVP_sha1(), cookie_secret, COOKIE_SECRET_LENGTH,
            buffer, length, result, &resultlength) == NULL) {
                free(buffer);
                return 0;
        }

        free(buffer);

        if (cookie_len == resultlength &&
            memcmp(result, cookie, resultlength) == 0)
                return 1;

        return 0;
}