view src/stream/ngx_stream_core_module.c @ 9300:5be23505292b

SSI: fixed incorrect or duplicate stub output. Following 3518:eb3aaf8bd2a9 (0.8.37), r->request_output is only set if there are data in the first buffer sent in the subrequest. As a result, following the change mentioned this flag cannot be used to prevent duplicate ngx_http_ssi_stub_output() calls, since it is not set if there was already some output, but the first buffer was empty. Still, when there are multiple subrequests, even an empty subrequest response might be delayed by the postpone filter, leading to a second call of ngx_http_ssi_stub_output() during finalization from ngx_http_writer() the subreqest buffers are released by the postpone filter. Since r->request_output is not set after the first call, this resulted in duplicate stub output. Additionally, checking only the first buffer might be wrong in some unusual cases. For example, the first buffer might be empty if $r->flush() is called before printing any data in the embedded Perl module. Depending on the postpone_output value and corresponding sizes, this issue can result in either duplicate or unexpected stub output, or "zero size buf in writer" alerts. Following 8124:f5515e727656 (1.23.4), it became slightly easier to reproduce the issue, as empty static files and empty cache items now result in a response with an empty buffer. Before the change, an empty proxied response can be used to reproduce the issue. Fix is check all buffers and set r->request_output if any non-empty buffers are sent. This ensures that all unusual cases of non-empty responses are covered, and also that r->request_output will be set after the first stub output, preventing duplicate output. Reported by Jan Gassen.
author Maxim Dounin <mdounin@mdounin.ru>
date Thu, 04 Jul 2024 17:41:28 +0300
parents 113e2438dbd4
children
line wrap: on
line source


/*
 * Copyright (C) Roman Arutyunyan
 * Copyright (C) Nginx, Inc.
 */


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


static ngx_int_t ngx_stream_core_preconfiguration(ngx_conf_t *cf);
static void *ngx_stream_core_create_main_conf(ngx_conf_t *cf);
static char *ngx_stream_core_init_main_conf(ngx_conf_t *cf, void *conf);
static void *ngx_stream_core_create_srv_conf(ngx_conf_t *cf);
static char *ngx_stream_core_merge_srv_conf(ngx_conf_t *cf, void *parent,
    void *child);
static char *ngx_stream_core_error_log(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);
static char *ngx_stream_core_server(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);
static char *ngx_stream_core_listen(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);
static char *ngx_stream_core_resolver(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);


static ngx_command_t  ngx_stream_core_commands[] = {

    { ngx_string("variables_hash_max_size"),
      NGX_STREAM_MAIN_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_num_slot,
      NGX_STREAM_MAIN_CONF_OFFSET,
      offsetof(ngx_stream_core_main_conf_t, variables_hash_max_size),
      NULL },

    { ngx_string("variables_hash_bucket_size"),
      NGX_STREAM_MAIN_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_num_slot,
      NGX_STREAM_MAIN_CONF_OFFSET,
      offsetof(ngx_stream_core_main_conf_t, variables_hash_bucket_size),
      NULL },

    { ngx_string("server"),
      NGX_STREAM_MAIN_CONF|NGX_CONF_BLOCK|NGX_CONF_NOARGS,
      ngx_stream_core_server,
      0,
      0,
      NULL },

    { ngx_string("listen"),
      NGX_STREAM_SRV_CONF|NGX_CONF_1MORE,
      ngx_stream_core_listen,
      NGX_STREAM_SRV_CONF_OFFSET,
      0,
      NULL },

    { ngx_string("error_log"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_1MORE,
      ngx_stream_core_error_log,
      NGX_STREAM_SRV_CONF_OFFSET,
      0,
      NULL },

    { ngx_string("resolver"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_1MORE,
      ngx_stream_core_resolver,
      NGX_STREAM_SRV_CONF_OFFSET,
      0,
      NULL },

    { ngx_string("resolver_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_core_srv_conf_t, resolver_timeout),
      NULL },

    { ngx_string("proxy_protocol_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_core_srv_conf_t, proxy_protocol_timeout),
      NULL },

    { ngx_string("tcp_nodelay"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_FLAG,
      ngx_conf_set_flag_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_core_srv_conf_t, tcp_nodelay),
      NULL },

    { ngx_string("preread_buffer_size"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_size_slot,
      NGX_STREAM_SRV_CONF_OFFSET,
      offsetof(ngx_stream_core_srv_conf_t, preread_buffer_size),
      NULL },

    { ngx_string("preread_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_core_srv_conf_t, preread_timeout),
      NULL },

      ngx_null_command
};


static ngx_stream_module_t  ngx_stream_core_module_ctx = {
    ngx_stream_core_preconfiguration,      /* preconfiguration */
    NULL,                                  /* postconfiguration */

    ngx_stream_core_create_main_conf,      /* create main configuration */
    ngx_stream_core_init_main_conf,        /* init main configuration */

    ngx_stream_core_create_srv_conf,       /* create server configuration */
    ngx_stream_core_merge_srv_conf         /* merge server configuration */
};


ngx_module_t  ngx_stream_core_module = {
    NGX_MODULE_V1,
    &ngx_stream_core_module_ctx,           /* module context */
    ngx_stream_core_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
};


void
ngx_stream_core_run_phases(ngx_stream_session_t *s)
{
    ngx_int_t                     rc;
    ngx_stream_phase_handler_t   *ph;
    ngx_stream_core_main_conf_t  *cmcf;

    cmcf = ngx_stream_get_module_main_conf(s, ngx_stream_core_module);

    ph = cmcf->phase_engine.handlers;

    while (ph[s->phase_handler].checker) {

        rc = ph[s->phase_handler].checker(s, &ph[s->phase_handler]);

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


ngx_int_t
ngx_stream_core_generic_phase(ngx_stream_session_t *s,
    ngx_stream_phase_handler_t *ph)
{
    ngx_int_t  rc;

    /*
     * generic phase checker,
     * used by all phases, except for preread and content
     */

    ngx_log_debug1(NGX_LOG_DEBUG_STREAM, s->connection->log, 0,
                   "generic phase: %ui", s->phase_handler);

    rc = ph->handler(s);

    if (rc == NGX_OK) {
        s->phase_handler = ph->next;
        return NGX_AGAIN;
    }

    if (rc == NGX_DECLINED) {
        s->phase_handler++;
        return NGX_AGAIN;
    }

    if (rc == NGX_AGAIN || rc == NGX_DONE) {
        return NGX_OK;
    }

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

    ngx_stream_finalize_session(s, rc);

    return NGX_OK;
}


ngx_int_t
ngx_stream_core_preread_phase(ngx_stream_session_t *s,
    ngx_stream_phase_handler_t *ph)
{
    size_t                       size;
    ssize_t                      n;
    ngx_int_t                    rc;
    ngx_connection_t            *c;
    ngx_stream_core_srv_conf_t  *cscf;

    c = s->connection;

    c->log->action = "prereading client data";

    cscf = ngx_stream_get_module_srv_conf(s, ngx_stream_core_module);

    if (c->read->timedout) {
        rc = NGX_STREAM_OK;

    } else if (c->read->timer_set) {
        rc = NGX_AGAIN;

    } else {
        rc = ph->handler(s);
    }

    while (rc == NGX_AGAIN) {

        if (c->buffer == NULL) {
            c->buffer = ngx_create_temp_buf(c->pool, cscf->preread_buffer_size);
            if (c->buffer == NULL) {
                rc = NGX_ERROR;
                break;
            }
        }

        size = c->buffer->end - c->buffer->last;

        if (size == 0) {
            ngx_log_error(NGX_LOG_ERR, c->log, 0, "preread buffer full");
            rc = NGX_STREAM_BAD_REQUEST;
            break;
        }

        if (c->read->eof) {
            rc = NGX_STREAM_OK;
            break;
        }

        if (!c->read->ready) {
            break;
        }

        n = c->recv(c, c->buffer->last, size);

        if (n == NGX_ERROR || n == 0) {
            rc = NGX_STREAM_OK;
            break;
        }

        if (n == NGX_AGAIN) {
            break;
        }

        c->buffer->last += n;

        rc = ph->handler(s);
    }

    if (rc == NGX_AGAIN) {
        if (ngx_handle_read_event(c->read, 0) != NGX_OK) {
            ngx_stream_finalize_session(s, NGX_STREAM_INTERNAL_SERVER_ERROR);
            return NGX_OK;
        }

        if (!c->read->timer_set) {
            ngx_add_timer(c->read, cscf->preread_timeout);
        }

        c->read->handler = ngx_stream_session_handler;

        return NGX_OK;
    }

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

    if (rc == NGX_OK) {
        s->phase_handler = ph->next;
        return NGX_AGAIN;
    }

    if (rc == NGX_DECLINED) {
        s->phase_handler++;
        return NGX_AGAIN;
    }

    if (rc == NGX_DONE) {
        return NGX_OK;
    }

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

    ngx_stream_finalize_session(s, rc);

    return NGX_OK;
}


ngx_int_t
ngx_stream_core_content_phase(ngx_stream_session_t *s,
    ngx_stream_phase_handler_t *ph)
{
    ngx_connection_t            *c;
    ngx_stream_core_srv_conf_t  *cscf;

    c = s->connection;

    c->log->action = NULL;

    cscf = ngx_stream_get_module_srv_conf(s, ngx_stream_core_module);

    if (c->type == SOCK_STREAM
        && cscf->tcp_nodelay
        && ngx_tcp_nodelay(c) != NGX_OK)
    {
        ngx_stream_finalize_session(s, NGX_STREAM_INTERNAL_SERVER_ERROR);
        return NGX_OK;
    }

    cscf->handler(s);

    return NGX_OK;
}


static ngx_int_t
ngx_stream_core_preconfiguration(ngx_conf_t *cf)
{
    return ngx_stream_variables_add_core_vars(cf);
}


static void *
ngx_stream_core_create_main_conf(ngx_conf_t *cf)
{
    ngx_stream_core_main_conf_t  *cmcf;

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

    if (ngx_array_init(&cmcf->servers, cf->pool, 4,
                       sizeof(ngx_stream_core_srv_conf_t *))
        != NGX_OK)
    {
        return NULL;
    }

    if (ngx_array_init(&cmcf->listen, cf->pool, 4, sizeof(ngx_stream_listen_t))
        != NGX_OK)
    {
        return NULL;
    }

    cmcf->variables_hash_max_size = NGX_CONF_UNSET_UINT;
    cmcf->variables_hash_bucket_size = NGX_CONF_UNSET_UINT;

    return cmcf;
}


static char *
ngx_stream_core_init_main_conf(ngx_conf_t *cf, void *conf)
{
    ngx_stream_core_main_conf_t *cmcf = conf;

    ngx_conf_init_uint_value(cmcf->variables_hash_max_size, 1024);
    ngx_conf_init_uint_value(cmcf->variables_hash_bucket_size, 64);

    cmcf->variables_hash_bucket_size =
               ngx_align(cmcf->variables_hash_bucket_size, ngx_cacheline_size);

    if (cmcf->ncaptures) {
        cmcf->ncaptures = (cmcf->ncaptures + 1) * 3;
    }

    return NGX_CONF_OK;
}


static void *
ngx_stream_core_create_srv_conf(ngx_conf_t *cf)
{
    ngx_stream_core_srv_conf_t  *cscf;

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

    /*
     * set by ngx_pcalloc():
     *
     *     cscf->handler = NULL;
     *     cscf->error_log = NULL;
     */

    cscf->file_name = cf->conf_file->file.name.data;
    cscf->line = cf->conf_file->line;
    cscf->resolver_timeout = NGX_CONF_UNSET_MSEC;
    cscf->proxy_protocol_timeout = NGX_CONF_UNSET_MSEC;
    cscf->tcp_nodelay = NGX_CONF_UNSET;
    cscf->preread_buffer_size = NGX_CONF_UNSET_SIZE;
    cscf->preread_timeout = NGX_CONF_UNSET_MSEC;

    return cscf;
}


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

    ngx_conf_merge_msec_value(conf->resolver_timeout,
                              prev->resolver_timeout, 30000);

    if (conf->resolver == NULL) {

        if (prev->resolver == NULL) {

            /*
             * create dummy resolver in stream {} context
             * to inherit it in all servers
             */

            prev->resolver = ngx_resolver_create(cf, NULL, 0);
            if (prev->resolver == NULL) {
                return NGX_CONF_ERROR;
            }
        }

        conf->resolver = prev->resolver;
    }

    if (conf->handler == NULL) {
        ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                      "no handler for server in %s:%ui",
                      conf->file_name, conf->line);
        return NGX_CONF_ERROR;
    }

    if (conf->error_log == NULL) {
        if (prev->error_log) {
            conf->error_log = prev->error_log;
        } else {
            conf->error_log = &cf->cycle->new_log;
        }
    }

    ngx_conf_merge_msec_value(conf->proxy_protocol_timeout,
                              prev->proxy_protocol_timeout, 30000);

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

    ngx_conf_merge_size_value(conf->preread_buffer_size,
                              prev->preread_buffer_size, 16384);

    ngx_conf_merge_msec_value(conf->preread_timeout,
                              prev->preread_timeout, 30000);

    return NGX_CONF_OK;
}


static char *
ngx_stream_core_error_log(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_stream_core_srv_conf_t  *cscf = conf;

    return ngx_log_set_log(cf, &cscf->error_log);
}


static char *
ngx_stream_core_server(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    char                         *rv;
    void                         *mconf;
    ngx_uint_t                    m;
    ngx_conf_t                    pcf;
    ngx_stream_module_t          *module;
    ngx_stream_conf_ctx_t        *ctx, *stream_ctx;
    ngx_stream_core_srv_conf_t   *cscf, **cscfp;
    ngx_stream_core_main_conf_t  *cmcf;

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

    stream_ctx = cf->ctx;
    ctx->main_conf = stream_ctx->main_conf;

    /* the server{}'s srv_conf */

    ctx->srv_conf = ngx_pcalloc(cf->pool,
                                sizeof(void *) * ngx_stream_max_module);
    if (ctx->srv_conf == NULL) {
        return NGX_CONF_ERROR;
    }

    for (m = 0; cf->cycle->modules[m]; m++) {
        if (cf->cycle->modules[m]->type != NGX_STREAM_MODULE) {
            continue;
        }

        module = cf->cycle->modules[m]->ctx;

        if (module->create_srv_conf) {
            mconf = module->create_srv_conf(cf);
            if (mconf == NULL) {
                return NGX_CONF_ERROR;
            }

            ctx->srv_conf[cf->cycle->modules[m]->ctx_index] = mconf;
        }
    }

    /* the server configuration context */

    cscf = ctx->srv_conf[ngx_stream_core_module.ctx_index];
    cscf->ctx = ctx;

    cmcf = ctx->main_conf[ngx_stream_core_module.ctx_index];

    cscfp = ngx_array_push(&cmcf->servers);
    if (cscfp == NULL) {
        return NGX_CONF_ERROR;
    }

    *cscfp = cscf;


    /* parse inside server{} */

    pcf = *cf;
    cf->ctx = ctx;
    cf->cmd_type = NGX_STREAM_SRV_CONF;

    rv = ngx_conf_parse(cf, NULL);

    *cf = pcf;

    if (rv == NGX_CONF_OK && !cscf->listen) {
        ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                      "no \"listen\" is defined for server in %s:%ui",
                      cscf->file_name, cscf->line);
        return NGX_CONF_ERROR;
    }

    return rv;
}


static char *
ngx_stream_core_listen(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_stream_core_srv_conf_t  *cscf = conf;

    ngx_str_t                    *value, size;
    ngx_url_t                     u;
    ngx_uint_t                    i, n, backlog;
    ngx_stream_listen_t          *ls, *als, *nls;
    ngx_stream_core_main_conf_t  *cmcf;

    cscf->listen = 1;

    value = cf->args->elts;

    ngx_memzero(&u, sizeof(ngx_url_t));

    u.url = value[1];
    u.listen = 1;

    if (ngx_parse_url(cf->pool, &u) != NGX_OK) {
        if (u.err) {
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "%s in \"%V\" of the \"listen\" directive",
                               u.err, &u.url);
        }

        return NGX_CONF_ERROR;
    }

    cmcf = ngx_stream_conf_get_module_main_conf(cf, ngx_stream_core_module);

    ls = ngx_array_push(&cmcf->listen);
    if (ls == NULL) {
        return NGX_CONF_ERROR;
    }

    ngx_memzero(ls, sizeof(ngx_stream_listen_t));

    ls->backlog = NGX_LISTEN_BACKLOG;
    ls->rcvbuf = -1;
    ls->sndbuf = -1;
    ls->type = SOCK_STREAM;
    ls->ctx = cf->ctx;

#if (NGX_HAVE_TCP_FASTOPEN)
    ls->fastopen = -1;
#endif

#if (NGX_HAVE_INET6)
    ls->ipv6only = 1;
#endif

    backlog = 0;

    for (i = 2; i < cf->args->nelts; i++) {

#if !(NGX_WIN32)
        if (ngx_strcmp(value[i].data, "udp") == 0) {
            ls->type = SOCK_DGRAM;
            continue;
        }
#endif

        if (ngx_strcmp(value[i].data, "bind") == 0) {
            ls->bind = 1;
            continue;
        }

#if (NGX_HAVE_TCP_FASTOPEN)
        if (ngx_strncmp(value[i].data, "fastopen=", 9) == 0) {
            ls->fastopen = ngx_atoi(value[i].data + 9, value[i].len - 9);
            ls->bind = 1;

            if (ls->fastopen == NGX_ERROR) {
                ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                   "invalid fastopen \"%V\"", &value[i]);
                return NGX_CONF_ERROR;
            }

            continue;
        }
#endif

        if (ngx_strncmp(value[i].data, "backlog=", 8) == 0) {
            ls->backlog = ngx_atoi(value[i].data + 8, value[i].len - 8);
            ls->bind = 1;

            if (ls->backlog == NGX_ERROR || ls->backlog == 0) {
                ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                   "invalid backlog \"%V\"", &value[i]);
                return NGX_CONF_ERROR;
            }

            backlog = 1;

            continue;
        }

        if (ngx_strncmp(value[i].data, "rcvbuf=", 7) == 0) {
            size.len = value[i].len - 7;
            size.data = value[i].data + 7;

            ls->rcvbuf = ngx_parse_size(&size);
            ls->bind = 1;

            if (ls->rcvbuf == NGX_ERROR) {
                ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                   "invalid rcvbuf \"%V\"", &value[i]);
                return NGX_CONF_ERROR;
            }

            continue;
        }

        if (ngx_strncmp(value[i].data, "sndbuf=", 7) == 0) {
            size.len = value[i].len - 7;
            size.data = value[i].data + 7;

            ls->sndbuf = ngx_parse_size(&size);
            ls->bind = 1;

            if (ls->sndbuf == NGX_ERROR) {
                ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                   "invalid sndbuf \"%V\"", &value[i]);
                return NGX_CONF_ERROR;
            }

            continue;
        }

        if (ngx_strncmp(value[i].data, "ipv6only=o", 10) == 0) {
#if (NGX_HAVE_INET6 && defined IPV6_V6ONLY)
            if (ngx_strcmp(&value[i].data[10], "n") == 0) {
                ls->ipv6only = 1;

            } else if (ngx_strcmp(&value[i].data[10], "ff") == 0) {
                ls->ipv6only = 0;

            } else {
                ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                   "invalid ipv6only flags \"%s\"",
                                   &value[i].data[9]);
                return NGX_CONF_ERROR;
            }

            ls->bind = 1;
            continue;
#else
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "bind ipv6only is not supported "
                               "on this platform");
            return NGX_CONF_ERROR;
#endif
        }

        if (ngx_strcmp(value[i].data, "reuseport") == 0) {
#if (NGX_HAVE_REUSEPORT)
            ls->reuseport = 1;
            ls->bind = 1;
#else
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "reuseport is not supported "
                               "on this platform, ignored");
#endif
            continue;
        }

        if (ngx_strcmp(value[i].data, "ssl") == 0) {
#if (NGX_STREAM_SSL)
            ngx_stream_ssl_conf_t  *sslcf;

            sslcf = ngx_stream_conf_get_module_srv_conf(cf,
                                                        ngx_stream_ssl_module);

            sslcf->listen = 1;
            sslcf->file = cf->conf_file->file.name.data;
            sslcf->line = cf->conf_file->line;

            ls->ssl = 1;

            continue;
#else
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "the \"ssl\" parameter requires "
                               "ngx_stream_ssl_module");
            return NGX_CONF_ERROR;
#endif
        }

        if (ngx_strncmp(value[i].data, "so_keepalive=", 13) == 0) {

            if (ngx_strcmp(&value[i].data[13], "on") == 0) {
                ls->so_keepalive = 1;

            } else if (ngx_strcmp(&value[i].data[13], "off") == 0) {
                ls->so_keepalive = 2;

            } else {

#if (NGX_HAVE_KEEPALIVE_TUNABLE)
                u_char     *p, *end;
                ngx_str_t   s;

                end = value[i].data + value[i].len;
                s.data = value[i].data + 13;

                p = ngx_strlchr(s.data, end, ':');
                if (p == NULL) {
                    p = end;
                }

                if (p > s.data) {
                    s.len = p - s.data;

                    ls->tcp_keepidle = ngx_parse_time(&s, 1);
                    if (ls->tcp_keepidle == (time_t) NGX_ERROR) {
                        goto invalid_so_keepalive;
                    }
                }

                s.data = (p < end) ? (p + 1) : end;

                p = ngx_strlchr(s.data, end, ':');
                if (p == NULL) {
                    p = end;
                }

                if (p > s.data) {
                    s.len = p - s.data;

                    ls->tcp_keepintvl = ngx_parse_time(&s, 1);
                    if (ls->tcp_keepintvl == (time_t) NGX_ERROR) {
                        goto invalid_so_keepalive;
                    }
                }

                s.data = (p < end) ? (p + 1) : end;

                if (s.data < end) {
                    s.len = end - s.data;

                    ls->tcp_keepcnt = ngx_atoi(s.data, s.len);
                    if (ls->tcp_keepcnt == NGX_ERROR) {
                        goto invalid_so_keepalive;
                    }
                }

                if (ls->tcp_keepidle == 0 && ls->tcp_keepintvl == 0
                    && ls->tcp_keepcnt == 0)
                {
                    goto invalid_so_keepalive;
                }

                ls->so_keepalive = 1;

#else

                ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                   "the \"so_keepalive\" parameter accepts "
                                   "only \"on\" or \"off\" on this platform");
                return NGX_CONF_ERROR;

#endif
            }

            ls->bind = 1;

            continue;

#if (NGX_HAVE_KEEPALIVE_TUNABLE)
        invalid_so_keepalive:

            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "invalid so_keepalive value: \"%s\"",
                               &value[i].data[13]);
            return NGX_CONF_ERROR;
#endif
        }

        if (ngx_strcmp(value[i].data, "proxy_protocol") == 0) {
            ls->proxy_protocol = 1;
            continue;
        }

        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "the invalid \"%V\" parameter", &value[i]);
        return NGX_CONF_ERROR;
    }

    if (ls->type == SOCK_DGRAM) {
        if (backlog) {
            return "\"backlog\" parameter is incompatible with \"udp\"";
        }

#if (NGX_STREAM_SSL)
        if (ls->ssl) {
            return "\"ssl\" parameter is incompatible with \"udp\"";
        }
#endif

        if (ls->so_keepalive) {
            return "\"so_keepalive\" parameter is incompatible with \"udp\"";
        }

        if (ls->proxy_protocol) {
            return "\"proxy_protocol\" parameter is incompatible with \"udp\"";
        }

#if (NGX_HAVE_TCP_FASTOPEN)
        if (ls->fastopen != -1) {
            return "\"fastopen\" parameter is incompatible with \"udp\"";
        }
#endif
    }

    for (n = 0; n < u.naddrs; n++) {

        for (i = 0; i < n; i++) {
            if (ngx_cmp_sockaddr(u.addrs[n].sockaddr, u.addrs[n].socklen,
                                 u.addrs[i].sockaddr, u.addrs[i].socklen, 1)
                == NGX_OK)
            {
                goto next;
            }
        }

        if (n != 0) {
            nls = ngx_array_push(&cmcf->listen);
            if (nls == NULL) {
                return NGX_CONF_ERROR;
            }

            *nls = *ls;

        } else {
            nls = ls;
        }

        nls->sockaddr = u.addrs[n].sockaddr;
        nls->socklen = u.addrs[n].socklen;
        nls->addr_text = u.addrs[n].name;
        nls->wildcard = ngx_inet_wildcard(nls->sockaddr);

        als = cmcf->listen.elts;

        for (i = 0; i < cmcf->listen.nelts - 1; i++) {
            if (nls->type != als[i].type) {
                continue;
            }

            if (ngx_cmp_sockaddr(als[i].sockaddr, als[i].socklen,
                                 nls->sockaddr, nls->socklen, 1)
                != NGX_OK)
            {
                continue;
            }

            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "duplicate \"%V\" address and port pair",
                               &nls->addr_text);
            return NGX_CONF_ERROR;
        }

    next:
        continue;
    }

    return NGX_CONF_OK;
}


static char *
ngx_stream_core_resolver(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_stream_core_srv_conf_t  *cscf = conf;

    ngx_str_t  *value;

    if (cscf->resolver) {
        return "is duplicate";
    }

    value = cf->args->elts;

    cscf->resolver = ngx_resolver_create(cf, &value[1], cf->args->nelts - 1);
    if (cscf->resolver == NULL) {
        return NGX_CONF_ERROR;
    }

    return NGX_CONF_OK;
}