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view src/stream/ngx_stream_ssl_module.c @ 7729:3bff3f397c05

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SSL: ssl_conf_command directive. With the ssl_conf_command directive it is now possible to set arbitrary OpenSSL configuration parameters as long as nginx is compiled with OpenSSL 1.0.2 or later. Full list of available configuration commands can be found in the SSL_CONF_cmd manual page (https://www.openssl.org/docs/man1.1.1/man3/SSL_CONF_cmd.html). In particular, this allows configuring PrioritizeChaCha option (ticket #1445): ssl_conf_command Options PrioritizeChaCha; It can be also used to configure TLSv1.3 ciphers in OpenSSL, which fails to configure them via the SSL_CTX_set_cipher_list() interface (ticket #1529): ssl_conf_command Ciphersuites TLS_CHACHA20_POLY1305_SHA256; Configuration commands are applied after nginx own configuration for SSL, so they can be used to override anything set by nginx. Note though that configuring OpenSSL directly with ssl_conf_command might result in a behaviour nginx does not expect, and should be done with care.
author Maxim Dounin <mdounin@mdounin.ru>
date Thu, 22 Oct 2020 18:00:22 +0300
parents ef7ee19776db
children 7ce28b4cc57e
line wrap: on
line source


/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_stream.h>


typedef ngx_int_t (*ngx_ssl_variable_handler_pt)(ngx_connection_t *c,
    ngx_pool_t *pool, ngx_str_t *s);


#define NGX_DEFAULT_CIPHERS     "HIGH:!aNULL:!MD5"
#define NGX_DEFAULT_ECDH_CURVE  "auto"


static ngx_int_t ngx_stream_ssl_handler(ngx_stream_session_t *s);
static ngx_int_t ngx_stream_ssl_init_connection(ngx_ssl_t *ssl,
    ngx_connection_t *c);
static void ngx_stream_ssl_handshake_handler(ngx_connection_t *c);
#ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME
int ngx_stream_ssl_servername(ngx_ssl_conn_t *ssl_conn, int *ad, void *arg);
#endif
#ifdef SSL_R_CERT_CB_ERROR
static int ngx_stream_ssl_certificate(ngx_ssl_conn_t *ssl_conn, void *arg);
#endif
static ngx_int_t ngx_stream_ssl_static_variable(ngx_stream_session_t *s,
    ngx_stream_variable_value_t *v, uintptr_t data);
static ngx_int_t ngx_stream_ssl_variable(ngx_stream_session_t *s,
    ngx_stream_variable_value_t *v, uintptr_t data);

static ngx_int_t ngx_stream_ssl_add_variables(ngx_conf_t *cf);
static void *ngx_stream_ssl_create_conf(ngx_conf_t *cf);
static char *ngx_stream_ssl_merge_conf(ngx_conf_t *cf, void *parent,
    void *child);

static ngx_int_t ngx_stream_ssl_compile_certificates(ngx_conf_t *cf,
    ngx_stream_ssl_conf_t *conf);

static char *ngx_stream_ssl_password_file(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);
static char *ngx_stream_ssl_session_cache(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);

static char *ngx_stream_ssl_conf_command_check(ngx_conf_t *cf, void *post,
    void *data);

static ngx_int_t ngx_stream_ssl_init(ngx_conf_t *cf);


static ngx_conf_bitmask_t  ngx_stream_ssl_protocols[] = {
    { ngx_string("SSLv2"), NGX_SSL_SSLv2 },
    { ngx_string("SSLv3"), NGX_SSL_SSLv3 },
    { ngx_string("TLSv1"), NGX_SSL_TLSv1 },
    { ngx_string("TLSv1.1"), NGX_SSL_TLSv1_1 },
    { ngx_string("TLSv1.2"), NGX_SSL_TLSv1_2 },
    { ngx_string("TLSv1.3"), NGX_SSL_TLSv1_3 },
    { ngx_null_string, 0 }
};


static ngx_conf_enum_t  ngx_stream_ssl_verify[] = {
    { ngx_string("off"), 0 },
    { ngx_string("on"), 1 },
    { ngx_string("optional"), 2 },
    { ngx_string("optional_no_ca"), 3 },
    { ngx_null_string, 0 }
};


static ngx_conf_post_t  ngx_stream_ssl_conf_command_post =
    { ngx_stream_ssl_conf_command_check };


static ngx_command_t  ngx_stream_ssl_commands[] = {

    { ngx_string("ssl_handshake_timeout"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_msec_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_ssl_conf_t, handshake_timeout),
      NULL },

    { ngx_string("ssl_certificate"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_str_array_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_ssl_conf_t, certificates),
      NULL },

    { ngx_string("ssl_certificate_key"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_str_array_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_ssl_conf_t, certificate_keys),
      NULL },

    { ngx_string("ssl_password_file"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
      ngx_stream_ssl_password_file,
      NGX_STREAM_SRV_CONF_OFFSET,
      0,
      NULL },

    { ngx_string("ssl_dhparam"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_ssl_conf_t, dhparam),
      NULL },

    { ngx_string("ssl_ecdh_curve"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_ssl_conf_t, ecdh_curve),
      NULL },

    { ngx_string("ssl_protocols"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_1MORE,
      ngx_conf_set_bitmask_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_ssl_conf_t, protocols),
      &ngx_stream_ssl_protocols },

    { ngx_string("ssl_ciphers"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_ssl_conf_t, ciphers),
      NULL },

    { ngx_string("ssl_verify_client"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_enum_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_ssl_conf_t, verify),
      &ngx_stream_ssl_verify },

    { ngx_string("ssl_verify_depth"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_num_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_ssl_conf_t, verify_depth),
      NULL },

    { ngx_string("ssl_client_certificate"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_ssl_conf_t, client_certificate),
      NULL },

    { ngx_string("ssl_trusted_certificate"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_ssl_conf_t, trusted_certificate),
      NULL },

    { ngx_string("ssl_prefer_server_ciphers"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_FLAG,
      ngx_conf_set_flag_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_ssl_conf_t, prefer_server_ciphers),
      NULL },

    { ngx_string("ssl_session_cache"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE12,
      ngx_stream_ssl_session_cache,
      NGX_STREAM_SRV_CONF_OFFSET,
      0,
      NULL },

    { ngx_string("ssl_session_tickets"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_FLAG,
      ngx_conf_set_flag_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_ssl_conf_t, session_tickets),
      NULL },

    { ngx_string("ssl_session_ticket_key"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_str_array_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_ssl_conf_t, session_ticket_keys),
      NULL },

    { ngx_string("ssl_session_timeout"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_sec_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_ssl_conf_t, session_timeout),
      NULL },

    { ngx_string("ssl_crl"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_ssl_conf_t, crl),
      NULL },

    { ngx_string("ssl_conf_command"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE2,
      ngx_conf_set_keyval_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_ssl_conf_t, conf_commands),
      &ngx_stream_ssl_conf_command_post },

      ngx_null_command
};


static ngx_stream_module_t  ngx_stream_ssl_module_ctx = {
    ngx_stream_ssl_add_variables,          /* preconfiguration */
    ngx_stream_ssl_init,                   /* postconfiguration */

    NULL,                                  /* create main configuration */
    NULL,                                  /* init main configuration */

    ngx_stream_ssl_create_conf,            /* create server configuration */
    ngx_stream_ssl_merge_conf              /* merge server configuration */
};


ngx_module_t  ngx_stream_ssl_module = {
    NGX_MODULE_V1,
    &ngx_stream_ssl_module_ctx,            /* module context */
    ngx_stream_ssl_commands,               /* module directives */
    NGX_STREAM_MODULE,                     /* module type */
    NULL,                                  /* init master */
    NULL,                                  /* init module */
    NULL,                                  /* init process */
    NULL,                                  /* init thread */
    NULL,                                  /* exit thread */
    NULL,                                  /* exit process */
    NULL,                                  /* exit master */
    NGX_MODULE_V1_PADDING
};


static ngx_stream_variable_t  ngx_stream_ssl_vars[] = {

    { ngx_string("ssl_protocol"), NULL, ngx_stream_ssl_static_variable,
      (uintptr_t) ngx_ssl_get_protocol, NGX_STREAM_VAR_CHANGEABLE, 0 },

    { ngx_string("ssl_cipher"), NULL, ngx_stream_ssl_static_variable,
      (uintptr_t) ngx_ssl_get_cipher_name, NGX_STREAM_VAR_CHANGEABLE, 0 },

    { ngx_string("ssl_ciphers"), NULL, ngx_stream_ssl_variable,
      (uintptr_t) ngx_ssl_get_ciphers, NGX_STREAM_VAR_CHANGEABLE, 0 },

    { ngx_string("ssl_curves"), NULL, ngx_stream_ssl_variable,
      (uintptr_t) ngx_ssl_get_curves, NGX_STREAM_VAR_CHANGEABLE, 0 },

    { ngx_string("ssl_session_id"), NULL, ngx_stream_ssl_variable,
      (uintptr_t) ngx_ssl_get_session_id, NGX_STREAM_VAR_CHANGEABLE, 0 },

    { ngx_string("ssl_session_reused"), NULL, ngx_stream_ssl_variable,
      (uintptr_t) ngx_ssl_get_session_reused, NGX_STREAM_VAR_CHANGEABLE, 0 },

    { ngx_string("ssl_server_name"), NULL, ngx_stream_ssl_variable,
      (uintptr_t) ngx_ssl_get_server_name, NGX_STREAM_VAR_CHANGEABLE, 0 },

    { ngx_string("ssl_client_cert"), NULL, ngx_stream_ssl_variable,
      (uintptr_t) ngx_ssl_get_certificate, NGX_STREAM_VAR_CHANGEABLE, 0 },

    { ngx_string("ssl_client_raw_cert"), NULL, ngx_stream_ssl_variable,
      (uintptr_t) ngx_ssl_get_raw_certificate,
      NGX_STREAM_VAR_CHANGEABLE, 0 },

    { ngx_string("ssl_client_escaped_cert"), NULL, ngx_stream_ssl_variable,
      (uintptr_t) ngx_ssl_get_escaped_certificate,
      NGX_STREAM_VAR_CHANGEABLE, 0 },

    { ngx_string("ssl_client_s_dn"), NULL, ngx_stream_ssl_variable,
      (uintptr_t) ngx_ssl_get_subject_dn, NGX_STREAM_VAR_CHANGEABLE, 0 },

    { ngx_string("ssl_client_i_dn"), NULL, ngx_stream_ssl_variable,
      (uintptr_t) ngx_ssl_get_issuer_dn, NGX_STREAM_VAR_CHANGEABLE, 0 },

    { ngx_string("ssl_client_serial"), NULL, ngx_stream_ssl_variable,
      (uintptr_t) ngx_ssl_get_serial_number, NGX_STREAM_VAR_CHANGEABLE, 0 },

    { ngx_string("ssl_client_fingerprint"), NULL, ngx_stream_ssl_variable,
      (uintptr_t) ngx_ssl_get_fingerprint, NGX_STREAM_VAR_CHANGEABLE, 0 },

    { ngx_string("ssl_client_verify"), NULL, ngx_stream_ssl_variable,
      (uintptr_t) ngx_ssl_get_client_verify, NGX_STREAM_VAR_CHANGEABLE, 0 },

    { ngx_string("ssl_client_v_start"), NULL, ngx_stream_ssl_variable,
      (uintptr_t) ngx_ssl_get_client_v_start, NGX_STREAM_VAR_CHANGEABLE, 0 },

    { ngx_string("ssl_client_v_end"), NULL, ngx_stream_ssl_variable,
      (uintptr_t) ngx_ssl_get_client_v_end, NGX_STREAM_VAR_CHANGEABLE, 0 },

    { ngx_string("ssl_client_v_remain"), NULL, ngx_stream_ssl_variable,
      (uintptr_t) ngx_ssl_get_client_v_remain, NGX_STREAM_VAR_CHANGEABLE, 0 },

      ngx_stream_null_variable
};


static ngx_str_t ngx_stream_ssl_sess_id_ctx = ngx_string("STREAM");


static ngx_int_t
ngx_stream_ssl_handler(ngx_stream_session_t *s)
{
    long                    rc;
    X509                   *cert;
    ngx_int_t               rv;
    ngx_connection_t       *c;
    ngx_stream_ssl_conf_t  *sslcf;

    if (!s->ssl) {
        return NGX_OK;
    }

    c = s->connection;

    sslcf = ngx_stream_get_module_srv_conf(s, ngx_stream_ssl_module);

    if (c->ssl == NULL) {
        c->log->action = "SSL handshaking";

        rv = ngx_stream_ssl_init_connection(&sslcf->ssl, c);

        if (rv != NGX_OK) {
            return rv;
        }
    }

    if (sslcf->verify) {
        rc = SSL_get_verify_result(c->ssl->connection);

        if (rc != X509_V_OK
            && (sslcf->verify != 3 || !ngx_ssl_verify_error_optional(rc)))
        {
            ngx_log_error(NGX_LOG_INFO, c->log, 0,
                          "client SSL certificate verify error: (%l:%s)",
                          rc, X509_verify_cert_error_string(rc));

            ngx_ssl_remove_cached_session(c->ssl->session_ctx,
                                       (SSL_get0_session(c->ssl->connection)));
            return NGX_ERROR;
        }

        if (sslcf->verify == 1) {
            cert = SSL_get_peer_certificate(c->ssl->connection);

            if (cert == NULL) {
                ngx_log_error(NGX_LOG_INFO, c->log, 0,
                              "client sent no required SSL certificate");

                ngx_ssl_remove_cached_session(c->ssl->session_ctx,
                                       (SSL_get0_session(c->ssl->connection)));
                return NGX_ERROR;
            }

            X509_free(cert);
        }
    }

    return NGX_OK;
}


static ngx_int_t
ngx_stream_ssl_init_connection(ngx_ssl_t *ssl, ngx_connection_t *c)
{
    ngx_int_t                    rc;
    ngx_stream_session_t        *s;
    ngx_stream_ssl_conf_t       *sslcf;
    ngx_stream_core_srv_conf_t  *cscf;

    s = c->data;

    cscf = ngx_stream_get_module_srv_conf(s, ngx_stream_core_module);

    if (cscf->tcp_nodelay && ngx_tcp_nodelay(c) != NGX_OK) {
        return NGX_ERROR;
    }

    if (ngx_ssl_create_connection(ssl, c, 0) != NGX_OK) {
        return NGX_ERROR;
    }

    rc = ngx_ssl_handshake(c);

    if (rc == NGX_ERROR) {
        return NGX_ERROR;
    }

    if (rc == NGX_AGAIN) {
        sslcf = ngx_stream_get_module_srv_conf(s, ngx_stream_ssl_module);

        ngx_add_timer(c->read, sslcf->handshake_timeout);

        c->ssl->handler = ngx_stream_ssl_handshake_handler;

        return NGX_AGAIN;
    }

    /* rc == NGX_OK */

    return NGX_OK;
}


static void
ngx_stream_ssl_handshake_handler(ngx_connection_t *c)
{
    ngx_stream_session_t  *s;

    s = c->data;

    if (!c->ssl->handshaked) {
        ngx_stream_finalize_session(s, NGX_STREAM_INTERNAL_SERVER_ERROR);
        return;
    }

    if (c->read->timer_set) {
        ngx_del_timer(c->read);
    }

    ngx_stream_core_run_phases(s);
}


#ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME

int
ngx_stream_ssl_servername(ngx_ssl_conn_t *ssl_conn, int *ad, void *arg)
{
    return SSL_TLSEXT_ERR_OK;
}

#endif


#ifdef SSL_R_CERT_CB_ERROR

int
ngx_stream_ssl_certificate(ngx_ssl_conn_t *ssl_conn, void *arg)
{
    ngx_str_t                    cert, key;
    ngx_uint_t                   i, nelts;
    ngx_connection_t            *c;
    ngx_stream_session_t        *s;
    ngx_stream_ssl_conf_t       *sslcf;
    ngx_stream_complex_value_t  *certs, *keys;

    c = ngx_ssl_get_connection(ssl_conn);

    if (c->ssl->handshaked) {
        return 0;
    }

    s = c->data;

    sslcf = arg;

    nelts = sslcf->certificate_values->nelts;
    certs = sslcf->certificate_values->elts;
    keys = sslcf->certificate_key_values->elts;

    for (i = 0; i < nelts; i++) {

        if (ngx_stream_complex_value(s, &certs[i], &cert) != NGX_OK) {
            return 0;
        }

        ngx_log_debug1(NGX_LOG_DEBUG_STREAM, c->log, 0,
                       "ssl cert: \"%s\"", cert.data);

        if (ngx_stream_complex_value(s, &keys[i], &key) != NGX_OK) {
            return 0;
        }

        ngx_log_debug1(NGX_LOG_DEBUG_STREAM, c->log, 0,
                       "ssl key: \"%s\"", key.data);

        if (ngx_ssl_connection_certificate(c, c->pool, &cert, &key,
                                           sslcf->passwords)
            != NGX_OK)
        {
            return 0;
        }
    }

    return 1;
}

#endif


static ngx_int_t
ngx_stream_ssl_static_variable(ngx_stream_session_t *s,
    ngx_stream_variable_value_t *v, uintptr_t data)
{
    ngx_ssl_variable_handler_pt  handler = (ngx_ssl_variable_handler_pt) data;

    size_t     len;
    ngx_str_t  str;

    if (s->connection->ssl) {

        (void) handler(s->connection, NULL, &str);

        v->data = str.data;

        for (len = 0; v->data[len]; len++) { /* void */ }

        v->len = len;
        v->valid = 1;
        v->no_cacheable = 0;
        v->not_found = 0;

        return NGX_OK;
    }

    v->not_found = 1;

    return NGX_OK;
}


static ngx_int_t
ngx_stream_ssl_variable(ngx_stream_session_t *s,
    ngx_stream_variable_value_t *v, uintptr_t data)
{
    ngx_ssl_variable_handler_pt  handler = (ngx_ssl_variable_handler_pt) data;

    ngx_str_t  str;

    if (s->connection->ssl) {

        if (handler(s->connection, s->connection->pool, &str) != NGX_OK) {
            return NGX_ERROR;
        }

        v->len = str.len;
        v->data = str.data;

        if (v->len) {
            v->valid = 1;
            v->no_cacheable = 0;
            v->not_found = 0;

            return NGX_OK;
        }
    }

    v->not_found = 1;

    return NGX_OK;
}


static ngx_int_t
ngx_stream_ssl_add_variables(ngx_conf_t *cf)
{
    ngx_stream_variable_t  *var, *v;

    for (v = ngx_stream_ssl_vars; v->name.len; v++) {
        var = ngx_stream_add_variable(cf, &v->name, v->flags);
        if (var == NULL) {
            return NGX_ERROR;
        }

        var->get_handler = v->get_handler;
        var->data = v->data;
    }

    return NGX_OK;
}


static void *
ngx_stream_ssl_create_conf(ngx_conf_t *cf)
{
    ngx_stream_ssl_conf_t  *scf;

    scf = ngx_pcalloc(cf->pool, sizeof(ngx_stream_ssl_conf_t));
    if (scf == NULL) {
        return NULL;
    }

    /*
     * set by ngx_pcalloc():
     *
     *     scf->listen = 0;
     *     scf->protocols = 0;
     *     scf->certificate_values = NULL;
     *     scf->dhparam = { 0, NULL };
     *     scf->ecdh_curve = { 0, NULL };
     *     scf->client_certificate = { 0, NULL };
     *     scf->trusted_certificate = { 0, NULL };
     *     scf->crl = { 0, NULL };
     *     scf->ciphers = { 0, NULL };
     *     scf->shm_zone = NULL;
     */

    scf->handshake_timeout = NGX_CONF_UNSET_MSEC;
    scf->certificates = NGX_CONF_UNSET_PTR;
    scf->certificate_keys = NGX_CONF_UNSET_PTR;
    scf->passwords = NGX_CONF_UNSET_PTR;
    scf->conf_commands = NGX_CONF_UNSET_PTR;
    scf->prefer_server_ciphers = NGX_CONF_UNSET;
    scf->verify = NGX_CONF_UNSET_UINT;
    scf->verify_depth = NGX_CONF_UNSET_UINT;
    scf->builtin_session_cache = NGX_CONF_UNSET;
    scf->session_timeout = NGX_CONF_UNSET;
    scf->session_tickets = NGX_CONF_UNSET;
    scf->session_ticket_keys = NGX_CONF_UNSET_PTR;

    return scf;
}


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

    ngx_pool_cleanup_t  *cln;

    ngx_conf_merge_msec_value(conf->handshake_timeout,
                         prev->handshake_timeout, 60000);

    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_TLSv1
                          |NGX_SSL_TLSv1_1|NGX_SSL_TLSv1_2));

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

    ngx_conf_merge_ptr_value(conf->certificates, prev->certificates, NULL);
    ngx_conf_merge_ptr_value(conf->certificate_keys, prev->certificate_keys,
                         NULL);

    ngx_conf_merge_ptr_value(conf->passwords, prev->passwords, NULL);

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

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

    ngx_conf_merge_str_value(conf->ecdh_curve, prev->ecdh_curve,
                         NGX_DEFAULT_ECDH_CURVE);

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

    ngx_conf_merge_ptr_value(conf->conf_commands, prev->conf_commands, NULL);


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

    if (!conf->listen) {
        return NGX_CONF_OK;
    }

    if (conf->certificates == NULL) {
        ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                      "no \"ssl_certificate\" is defined for "
                      "the \"listen ... ssl\" directive in %s:%ui",
                      conf->file, conf->line);
        return NGX_CONF_ERROR;
    }

    if (conf->certificate_keys == NULL) {
        ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                      "no \"ssl_certificate_key\" is defined for "
                      "the \"listen ... ssl\" directive in %s:%ui",
                      conf->file, conf->line);
        return NGX_CONF_ERROR;
    }

    if (conf->certificate_keys->nelts < conf->certificates->nelts) {
        ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                      "no \"ssl_certificate_key\" is defined "
                      "for certificate \"%V\" and "
                      "the \"listen ... ssl\" directive in %s:%ui",
                      ((ngx_str_t *) conf->certificates->elts)
                      + conf->certificates->nelts - 1,
                      conf->file, conf->line);
        return NGX_CONF_ERROR;
    }

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

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

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

#ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME
    SSL_CTX_set_tlsext_servername_callback(conf->ssl.ctx,
                                           ngx_stream_ssl_servername);
#endif

    if (ngx_stream_ssl_compile_certificates(cf, conf) != NGX_OK) {
        return NGX_CONF_ERROR;
    }

    if (conf->certificate_values) {

#ifdef SSL_R_CERT_CB_ERROR

        /* install callback to lookup certificates */

        SSL_CTX_set_cert_cb(conf->ssl.ctx, ngx_stream_ssl_certificate, conf);

#else
        ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                      "variables in "
                      "\"ssl_certificate\" and \"ssl_certificate_key\" "
                      "directives are not supported on this platform");
        return NGX_CONF_ERROR;
#endif

    } else {

        /* configure certificates */

        if (ngx_ssl_certificates(cf, &conf->ssl, conf->certificates,
                                 conf->certificate_keys, conf->passwords)
            != NGX_OK)
        {
            return NGX_CONF_ERROR;
        }
    }

    if (ngx_ssl_ciphers(cf, &conf->ssl, &conf->ciphers,
                        conf->prefer_server_ciphers)
        != NGX_OK)
    {
        return NGX_CONF_ERROR;
    }

    if (conf->verify) {

        if (conf->client_certificate.len == 0 && conf->verify != 3) {
            ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                          "no ssl_client_certificate for ssl_verify_client");
            return NGX_CONF_ERROR;
        }

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

        if (ngx_ssl_trusted_certificate(cf, &conf->ssl,
                                        &conf->trusted_certificate,
                                        conf->verify_depth)
            != NGX_OK)
        {
            return NGX_CONF_ERROR;
        }

        if (ngx_ssl_crl(cf, &conf->ssl, &conf->crl) != NGX_OK) {
            return NGX_CONF_ERROR;
        }
    }

    if (ngx_ssl_dhparam(cf, &conf->ssl, &conf->dhparam) != NGX_OK) {
        return NGX_CONF_ERROR;
    }

    if (ngx_ssl_ecdh_curve(cf, &conf->ssl, &conf->ecdh_curve) != NGX_OK) {
        return NGX_CONF_ERROR;
    }

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

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

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

    ngx_conf_merge_value(conf->session_tickets,
                         prev->session_tickets, 1);

#ifdef SSL_OP_NO_TICKET
    if (!conf->session_tickets) {
        SSL_CTX_set_options(conf->ssl.ctx, SSL_OP_NO_TICKET);
    }
#endif

    ngx_conf_merge_ptr_value(conf->session_ticket_keys,
                         prev->session_ticket_keys, NULL);

    if (ngx_ssl_session_ticket_keys(cf, &conf->ssl, conf->session_ticket_keys)
        != NGX_OK)
    {
        return NGX_CONF_ERROR;
    }

    if (ngx_ssl_conf_commands(cf, &conf->ssl, conf->conf_commands) != NGX_OK) {
        return NGX_CONF_ERROR;
    }

    return NGX_CONF_OK;
}


static ngx_int_t
ngx_stream_ssl_compile_certificates(ngx_conf_t *cf,
    ngx_stream_ssl_conf_t *conf)
{
    ngx_str_t                           *cert, *key;
    ngx_uint_t                           i, nelts;
    ngx_stream_complex_value_t          *cv;
    ngx_stream_compile_complex_value_t   ccv;

    cert = conf->certificates->elts;
    key = conf->certificate_keys->elts;
    nelts = conf->certificates->nelts;

    for (i = 0; i < nelts; i++) {

        if (ngx_stream_script_variables_count(&cert[i])) {
            goto found;
        }

        if (ngx_stream_script_variables_count(&key[i])) {
            goto found;
        }
    }

    return NGX_OK;

found:

    conf->certificate_values = ngx_array_create(cf->pool, nelts,
                                           sizeof(ngx_stream_complex_value_t));
    if (conf->certificate_values == NULL) {
        return NGX_ERROR;
    }

    conf->certificate_key_values = ngx_array_create(cf->pool, nelts,
                                           sizeof(ngx_stream_complex_value_t));
    if (conf->certificate_key_values == NULL) {
        return NGX_ERROR;
    }

    for (i = 0; i < nelts; i++) {

        cv = ngx_array_push(conf->certificate_values);
        if (cv == NULL) {
            return NGX_ERROR;
        }

        ngx_memzero(&ccv, sizeof(ngx_stream_compile_complex_value_t));

        ccv.cf = cf;
        ccv.value = &cert[i];
        ccv.complex_value = cv;
        ccv.zero = 1;

        if (ngx_stream_compile_complex_value(&ccv) != NGX_OK) {
            return NGX_ERROR;
        }

        cv = ngx_array_push(conf->certificate_key_values);
        if (cv == NULL) {
            return NGX_ERROR;
        }

        ngx_memzero(&ccv, sizeof(ngx_stream_compile_complex_value_t));

        ccv.cf = cf;
        ccv.value = &key[i];
        ccv.complex_value = cv;
        ccv.zero = 1;

        if (ngx_stream_compile_complex_value(&ccv) != NGX_OK) {
            return NGX_ERROR;
        }
    }

    conf->passwords = ngx_ssl_preserve_passwords(cf, conf->passwords);
    if (conf->passwords == NULL) {
        return NGX_ERROR;
    }

    return NGX_OK;
}


static char *
ngx_stream_ssl_password_file(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_stream_ssl_conf_t  *scf = conf;

    ngx_str_t  *value;

    if (scf->passwords != NGX_CONF_UNSET_PTR) {
        return "is duplicate";
    }

    value = cf->args->elts;

    scf->passwords = ngx_ssl_read_password_file(cf, &value[1]);

    if (scf->passwords == NULL) {
        return NGX_CONF_ERROR;
    }

    return NGX_CONF_OK;
}


static char *
ngx_stream_ssl_session_cache(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_stream_ssl_conf_t  *scf = 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) {
            scf->builtin_session_cache = NGX_SSL_NO_SCACHE;
            continue;
        }

        if (ngx_strcmp(value[i].data, "none") == 0) {
            scf->builtin_session_cache = NGX_SSL_NONE_SCACHE;
            continue;
        }

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

            scf->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;
            }

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

            scf->shm_zone->init = ngx_ssl_session_cache_init;

            continue;
        }

        goto invalid;
    }

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


static char *
ngx_stream_ssl_conf_command_check(ngx_conf_t *cf, void *post, void *data)
{
#ifndef SSL_CONF_FLAG_FILE
    return "is not supported on this platform";
#endif

    return NGX_CONF_OK;
}


static ngx_int_t
ngx_stream_ssl_init(ngx_conf_t *cf)
{
    ngx_stream_handler_pt        *h;
    ngx_stream_core_main_conf_t  *cmcf;

    cmcf = ngx_stream_conf_get_module_main_conf(cf, ngx_stream_core_module);

    h = ngx_array_push(&cmcf->phases[NGX_STREAM_SSL_PHASE].handlers);
    if (h == NULL) {
        return NGX_ERROR;
    }

    *h = ngx_stream_ssl_handler;

    return NGX_OK;
}