ngx_http_ssl_module.c

Nginx是一个高性能的HTTP和反向代理服务器

{
    ngx_http_ssl_srv_conf_t  *sscf;

    sscf = ngx_pcalloc(cf->pool, sizeof(ngx_http_ssl_srv_conf_t));
    if (sscf == NULL) {
        return NGX_CONF_ERROR;
    }

    /*
     * set by ngx_pcalloc():
     *
     *     sscf->protocols = 0;
     *     sscf->certificate.len = 0;
     *     sscf->certificate.data = NULL;
     *     sscf->certificate_key.len = 0;
     *     sscf->certificate_key.data = NULL;
     *     sscf->client_certificate.len = 0;
     *     sscf->client_certificate.data = NULL;
     *     sscf->ciphers.len = 0;
     *     sscf->ciphers.data = NULL;
     *     sscf->shm_zone = NULL;
     */

    sscf->enable = NGX_CONF_UNSET;
    sscf->verify = NGX_CONF_UNSET;
    sscf->verify_depth = NGX_CONF_UNSET;
    sscf->prefer_server_ciphers = NGX_CONF_UNSET;
    sscf->builtin_session_cache = NGX_CONF_UNSET;
    sscf->session_timeout = NGX_CONF_UNSET;

    return sscf;
}


static char *
ngx_http_ssl_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child)
{
    ngx_http_ssl_srv_conf_t *prev = parent;
    ngx_http_ssl_srv_conf_t *conf = child;

    ngx_pool_cleanup_t  *cln;

    ngx_conf_merge_value(conf->enable, prev->enable, 0);

    if (conf->enable == 0) {
        return NGX_CONF_OK;
    }

    ngx_conf_merge_value(conf->session_timeout,
                         prev->session_timeout, 300);

    ngx_conf_merge_value(conf->prefer_server_ciphers,
                         prev->prefer_server_ciphers, 0);

    ngx_conf_merge_bitmask_value(conf->protocols, prev->protocols,
                         (NGX_CONF_BITMASK_SET
                          |NGX_SSL_SSLv2|NGX_SSL_SSLv3|NGX_SSL_TLSv1));

    ngx_conf_merge_value(conf->verify, prev->verify, 0);
    ngx_conf_merge_value(conf->verify_depth, prev->verify_depth, 1);

    ngx_conf_merge_str_value(conf->certificate, prev->certificate,
                         NGX_DEFLAUT_CERTIFICATE);

    ngx_conf_merge_str_value(conf->certificate_key, prev->certificate_key,
                         NGX_DEFLAUT_CERTIFICATE_KEY);

    ngx_conf_merge_str_value(conf->client_certificate, prev->client_certificate,
                         "");

    ngx_conf_merge_str_value(conf->ciphers, prev->ciphers, NGX_DEFLAUT_CIPHERS);


    conf->ssl.log = cf->log;

    if (ngx_ssl_create(&conf->ssl, conf->protocols, conf) != NGX_OK) {
        return NGX_CONF_ERROR;
    }

#ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME

    if (SSL_CTX_set_tlsext_servername_callback(conf->ssl.ctx,
                                               ngx_http_ssl_servername)
        == 0)
    {
        ngx_ssl_error(NGX_LOG_EMERG, cf->log, 0,
                      "SSL_CTX_set_tlsext_servername_callback() failed");
        return NGX_CONF_ERROR;
    }

#endif

    cln = ngx_pool_cleanup_add(cf->pool, 0);
    if (cln == NULL) {
        return NGX_CONF_ERROR;
    }

    cln->handler = ngx_ssl_cleanup_ctx;
    cln->data = &conf->ssl;

    if (ngx_ssl_certificate(cf, &conf->ssl, &conf->certificate,
                            &conf->certificate_key)
        != NGX_OK)
    {
        return NGX_CONF_ERROR;
    }

    if (SSL_CTX_set_cipher_list(conf->ssl.ctx,
                                (const char *) conf->ciphers.data)
        == 0)
    {
        ngx_ssl_error(NGX_LOG_EMERG, cf->log, 0,
                      "SSL_CTX_set_cipher_list(\"%V\") failed",
                      &conf->ciphers);
    }

    if (conf->verify) {
        if (ngx_ssl_client_certificate(cf, &conf->ssl,
                                       &conf->client_certificate,
                                       conf->verify_depth)
            != NGX_OK)
        {
            return NGX_CONF_ERROR;
        }
    }

#ifdef SSL_OP_CIPHER_SERVER_PREFERENCE

    if (conf->prefer_server_ciphers) {
        SSL_CTX_set_options(conf->ssl.ctx, SSL_OP_CIPHER_SERVER_PREFERENCE);
    }

#endif

    /* a temporary 512-bit RSA key is required for export versions of MSIE */
    if (ngx_ssl_generate_rsa512_key(&conf->ssl) != NGX_OK) {
        return NGX_CONF_ERROR;
    }

    ngx_conf_merge_value(conf->builtin_session_cache,
                         prev->builtin_session_cache, NGX_SSL_NO_SCACHE);

    if (conf->shm_zone == NULL) {
        conf->shm_zone = prev->shm_zone;
    }

    if (ngx_ssl_session_cache(&conf->ssl, &ngx_http_ssl_sess_id_ctx,
                              conf->builtin_session_cache,
                              conf->shm_zone, conf->session_timeout)
        != NGX_OK)
    {
        return NGX_CONF_ERROR;
    }

    return NGX_CONF_OK;
}


static char *
ngx_http_ssl_session_cache(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_ssl_srv_conf_t *sscf = conf;

    size_t       len;
    ngx_str_t   *value, name, size;
    ngx_int_t    n;
    ngx_uint_t   i, j;

    value = cf->args->elts;

    for (i = 1; i < cf->args->nelts; i++) {

        if (ngx_strcmp(value[i].data, "off") == 0) {
            sscf->builtin_session_cache = NGX_SSL_NO_SCACHE;
            continue;
        }

        if (ngx_strcmp(value[i].data, "builtin") == 0) {
            sscf->builtin_session_cache = NGX_SSL_DFLT_BUILTIN_SCACHE;
            continue;
        }

        if (value[i].len > sizeof("builtin:") - 1
            && ngx_strncmp(value[i].data, "builtin:", sizeof("builtin:") - 1)
               == 0)
        {
            n = ngx_atoi(value[i].data + sizeof("builtin:") - 1,
                         value[i].len - (sizeof("builtin:") - 1));

            if (n == NGX_ERROR) {
                goto invalid;
            }

            sscf->builtin_session_cache = n;

            continue;
        }

        if (value[i].len > sizeof("shared:") - 1
            && ngx_strncmp(value[i].data, "shared:", sizeof("shared:") - 1)
               == 0)
        {
            len = 0;

            for (j = sizeof("shared:") - 1; j < value[i].len; j++) {
                if (value[i].data[j] == ':') {
                    break;
                }

                len++;
            }

            if (len == 0) {
                goto invalid;
            }

            name.len = len;
            name.data = value[i].data + sizeof("shared:") - 1;

            size.len = value[i].len - j - 1;
            size.data = name.data + len + 1;

            n = ngx_parse_size(&size);

            if (n == NGX_ERROR) {
                goto invalid;
            }

            if (n < (ngx_int_t) (8 * ngx_pagesize)) {
                ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                   "session cache \"%V\" is too small",
                                   &value[i]);

                return NGX_CONF_ERROR;
            }

            sscf->shm_zone = ngx_shared_memory_add(cf, &name, n,
                                                   &ngx_http_ssl_module);
            if (sscf->shm_zone == NULL) {
                return NGX_CONF_ERROR;
            }

            continue;
        }

        goto invalid;
    }

    if (sscf->shm_zone && sscf->builtin_session_cache == NGX_CONF_UNSET) {
        sscf->builtin_session_cache = NGX_SSL_NO_BUILTIN_SCACHE;
    }

    return NGX_CONF_OK;

invalid:

    ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                       "invalid session cache \"%V\"", &value[i]);

    return NGX_CONF_ERROR;
}


#if !defined (SSL_OP_CIPHER_SERVER_PREFERENCE)

static char *
ngx_http_ssl_nosupported(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                       "\"%V\" directive is available only in %s,",
                       &cmd->name, cmd->post);

    return NGX_CONF_ERROR;
}

#endif