Mercurial > hg > nginx

view src/http/v2/ngx_http_v2_module.c @ 7975:a7a77549265e

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
HTTP/2: fixed sendfile() aio handling. With sendfile() in threads ("aio threads; sendfile on;"), client connection can block on writing, waiting for sendfile() to complete. In HTTP/2 this might result in the request hang, since an attempt to continue processing in thread event handler will call request's write event handler, which is usually stopped by ngx_http_v2_send_chain(): it does nothing if there are no additional data and stream->queued is set. Further, HTTP/2 resets stream's c->write->ready to 0 if writing blocks, so just fixing ngx_http_v2_send_chain() is not enough. Can be reproduced with test suite on Linux with: TEST_NGINX_GLOBALS_HTTP="aio threads; sendfile on;" prove h2*.t The following tests currently fail: h2_keepalive.t, h2_priority.t, h2_proxy_max_temp_file_size.t, h2.t, h2_trailers.t. Similarly, sendfile() with AIO preloading on FreeBSD can block as well, with similar results. This is, however, harder to reproduce, especially on modern FreeBSD systems, since sendfile() usually does not return EBUSY. Fix is to modify ngx_http_v2_send_chain() so it actually tries to send data to the main connection when called, and to make sure that c->write->ready is set by the relevant event handlers.
author Maxim Dounin <mdounin@mdounin.ru>
date Thu, 25 Nov 2021 22:02:10 +0300
parents 827202ca1269
children 08ef02ad5c54
line wrap: on
line source


/*
 * Copyright (C) Nginx, Inc.
 * Copyright (C) Valentin V. Bartenev
 */


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_http.h>
#include <ngx_http_v2_module.h>


static ngx_int_t ngx_http_v2_add_variables(ngx_conf_t *cf);

static ngx_int_t ngx_http_v2_variable(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data);

static ngx_int_t ngx_http_v2_module_init(ngx_cycle_t *cycle);

static void *ngx_http_v2_create_main_conf(ngx_conf_t *cf);
static char *ngx_http_v2_init_main_conf(ngx_conf_t *cf, void *conf);
static void *ngx_http_v2_create_srv_conf(ngx_conf_t *cf);
static char *ngx_http_v2_merge_srv_conf(ngx_conf_t *cf, void *parent,
    void *child);
static void *ngx_http_v2_create_loc_conf(ngx_conf_t *cf);
static char *ngx_http_v2_merge_loc_conf(ngx_conf_t *cf, void *parent,
    void *child);

static char *ngx_http_v2_push(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);

static char *ngx_http_v2_recv_buffer_size(ngx_conf_t *cf, void *post,
    void *data);
static char *ngx_http_v2_pool_size(ngx_conf_t *cf, void *post, void *data);
static char *ngx_http_v2_preread_size(ngx_conf_t *cf, void *post, void *data);
static char *ngx_http_v2_streams_index_mask(ngx_conf_t *cf, void *post,
    void *data);
static char *ngx_http_v2_chunk_size(ngx_conf_t *cf, void *post, void *data);
static char *ngx_http_v2_obsolete(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);


static ngx_conf_deprecated_t  ngx_http_v2_recv_timeout_deprecated = {
    ngx_conf_deprecated, "http2_recv_timeout", "client_header_timeout"
};

static ngx_conf_deprecated_t  ngx_http_v2_idle_timeout_deprecated = {
    ngx_conf_deprecated, "http2_idle_timeout", "keepalive_timeout"
};

static ngx_conf_deprecated_t  ngx_http_v2_max_requests_deprecated = {
    ngx_conf_deprecated, "http2_max_requests", "keepalive_requests"
};

static ngx_conf_deprecated_t  ngx_http_v2_max_field_size_deprecated = {
    ngx_conf_deprecated, "http2_max_field_size", "large_client_header_buffers"
};

static ngx_conf_deprecated_t  ngx_http_v2_max_header_size_deprecated = {
    ngx_conf_deprecated, "http2_max_header_size", "large_client_header_buffers"
};


static ngx_conf_post_t  ngx_http_v2_recv_buffer_size_post =
    { ngx_http_v2_recv_buffer_size };
static ngx_conf_post_t  ngx_http_v2_pool_size_post =
    { ngx_http_v2_pool_size };
static ngx_conf_post_t  ngx_http_v2_preread_size_post =
    { ngx_http_v2_preread_size };
static ngx_conf_post_t  ngx_http_v2_streams_index_mask_post =
    { ngx_http_v2_streams_index_mask };
static ngx_conf_post_t  ngx_http_v2_chunk_size_post =
    { ngx_http_v2_chunk_size };


static ngx_command_t  ngx_http_v2_commands[] = {

    { ngx_string("http2_recv_buffer_size"),
      NGX_HTTP_MAIN_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_size_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(ngx_http_v2_main_conf_t, recv_buffer_size),
      &ngx_http_v2_recv_buffer_size_post },

    { ngx_string("http2_pool_size"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_size_slot,
      NGX_HTTP_SRV_CONF_OFFSET,
      offsetof(ngx_http_v2_srv_conf_t, pool_size),
      &ngx_http_v2_pool_size_post },

    { ngx_string("http2_max_concurrent_streams"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_num_slot,
      NGX_HTTP_SRV_CONF_OFFSET,
      offsetof(ngx_http_v2_srv_conf_t, concurrent_streams),
      NULL },

    { ngx_string("http2_max_concurrent_pushes"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_num_slot,
      NGX_HTTP_SRV_CONF_OFFSET,
      offsetof(ngx_http_v2_srv_conf_t, concurrent_pushes),
      NULL },

    { ngx_string("http2_max_requests"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
      ngx_http_v2_obsolete,
      0,
      0,
      &ngx_http_v2_max_requests_deprecated },

    { ngx_string("http2_max_field_size"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
      ngx_http_v2_obsolete,
      0,
      0,
      &ngx_http_v2_max_field_size_deprecated },

    { ngx_string("http2_max_header_size"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
      ngx_http_v2_obsolete,
      0,
      0,
      &ngx_http_v2_max_header_size_deprecated },

    { ngx_string("http2_body_preread_size"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_size_slot,
      NGX_HTTP_SRV_CONF_OFFSET,
      offsetof(ngx_http_v2_srv_conf_t, preread_size),
      &ngx_http_v2_preread_size_post },

    { ngx_string("http2_streams_index_size"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_num_slot,
      NGX_HTTP_SRV_CONF_OFFSET,
      offsetof(ngx_http_v2_srv_conf_t, streams_index_mask),
      &ngx_http_v2_streams_index_mask_post },

    { ngx_string("http2_recv_timeout"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
      ngx_http_v2_obsolete,
      0,
      0,
      &ngx_http_v2_recv_timeout_deprecated },

    { ngx_string("http2_idle_timeout"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
      ngx_http_v2_obsolete,
      0,
      0,
      &ngx_http_v2_idle_timeout_deprecated },

    { ngx_string("http2_chunk_size"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_size_slot,
      NGX_HTTP_LOC_CONF_OFFSET,
      offsetof(ngx_http_v2_loc_conf_t, chunk_size),
      &ngx_http_v2_chunk_size_post },

    { ngx_string("http2_push_preload"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
      ngx_conf_set_flag_slot,
      NGX_HTTP_LOC_CONF_OFFSET,
      offsetof(ngx_http_v2_loc_conf_t, push_preload),
      NULL },

    { ngx_string("http2_push"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
      ngx_http_v2_push,
      NGX_HTTP_LOC_CONF_OFFSET,
      0,
      NULL },

      ngx_null_command
};


static ngx_http_module_t  ngx_http_v2_module_ctx = {
    ngx_http_v2_add_variables,             /* preconfiguration */
    NULL,                                  /* postconfiguration */

    ngx_http_v2_create_main_conf,          /* create main configuration */
    ngx_http_v2_init_main_conf,            /* init main configuration */

    ngx_http_v2_create_srv_conf,           /* create server configuration */
    ngx_http_v2_merge_srv_conf,            /* merge server configuration */

    ngx_http_v2_create_loc_conf,           /* create location configuration */
    ngx_http_v2_merge_loc_conf             /* merge location configuration */
};


ngx_module_t  ngx_http_v2_module = {
    NGX_MODULE_V1,
    &ngx_http_v2_module_ctx,               /* module context */
    ngx_http_v2_commands,                  /* module directives */
    NGX_HTTP_MODULE,                       /* module type */
    NULL,                                  /* init master */
    ngx_http_v2_module_init,               /* init module */
    NULL,                                  /* init process */
    NULL,                                  /* init thread */
    NULL,                                  /* exit thread */
    NULL,                                  /* exit process */
    NULL,                                  /* exit master */
    NGX_MODULE_V1_PADDING
};


static ngx_http_variable_t  ngx_http_v2_vars[] = {

    { ngx_string("http2"), NULL,
      ngx_http_v2_variable, 0, 0, 0 },

      ngx_http_null_variable
};


static ngx_int_t
ngx_http_v2_add_variables(ngx_conf_t *cf)
{
    ngx_http_variable_t  *var, *v;

    for (v = ngx_http_v2_vars; v->name.len; v++) {
        var = ngx_http_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 ngx_int_t
ngx_http_v2_variable(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{

    if (r->stream) {
#if (NGX_HTTP_SSL)

        if (r->connection->ssl) {
            v->len = sizeof("h2") - 1;
            v->valid = 1;
            v->no_cacheable = 0;
            v->not_found = 0;
            v->data = (u_char *) "h2";

            return NGX_OK;
        }

#endif
        v->len = sizeof("h2c") - 1;
        v->valid = 1;
        v->no_cacheable = 0;
        v->not_found = 0;
        v->data = (u_char *) "h2c";

        return NGX_OK;
    }

    *v = ngx_http_variable_null_value;

    return NGX_OK;
}


static ngx_int_t
ngx_http_v2_module_init(ngx_cycle_t *cycle)
{
    return NGX_OK;
}


static void *
ngx_http_v2_create_main_conf(ngx_conf_t *cf)
{
    ngx_http_v2_main_conf_t  *h2mcf;

    h2mcf = ngx_pcalloc(cf->pool, sizeof(ngx_http_v2_main_conf_t));
    if (h2mcf == NULL) {
        return NULL;
    }

    h2mcf->recv_buffer_size = NGX_CONF_UNSET_SIZE;

    return h2mcf;
}


static char *
ngx_http_v2_init_main_conf(ngx_conf_t *cf, void *conf)
{
    ngx_http_v2_main_conf_t *h2mcf = conf;

    ngx_conf_init_size_value(h2mcf->recv_buffer_size, 256 * 1024);

    return NGX_CONF_OK;
}


static void *
ngx_http_v2_create_srv_conf(ngx_conf_t *cf)
{
    ngx_http_v2_srv_conf_t  *h2scf;

    h2scf = ngx_pcalloc(cf->pool, sizeof(ngx_http_v2_srv_conf_t));
    if (h2scf == NULL) {
        return NULL;
    }

    h2scf->pool_size = NGX_CONF_UNSET_SIZE;

    h2scf->concurrent_streams = NGX_CONF_UNSET_UINT;
    h2scf->concurrent_pushes = NGX_CONF_UNSET_UINT;

    h2scf->preread_size = NGX_CONF_UNSET_SIZE;

    h2scf->streams_index_mask = NGX_CONF_UNSET_UINT;

    return h2scf;
}


static char *
ngx_http_v2_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child)
{
    ngx_http_v2_srv_conf_t *prev = parent;
    ngx_http_v2_srv_conf_t *conf = child;

    ngx_conf_merge_size_value(conf->pool_size, prev->pool_size, 4096);

    ngx_conf_merge_uint_value(conf->concurrent_streams,
                              prev->concurrent_streams, 128);
    ngx_conf_merge_uint_value(conf->concurrent_pushes,
                              prev->concurrent_pushes, 10);

    ngx_conf_merge_size_value(conf->preread_size, prev->preread_size, 65536);

    ngx_conf_merge_uint_value(conf->streams_index_mask,
                              prev->streams_index_mask, 32 - 1);

    return NGX_CONF_OK;
}


static void *
ngx_http_v2_create_loc_conf(ngx_conf_t *cf)
{
    ngx_http_v2_loc_conf_t  *h2lcf;

    h2lcf = ngx_pcalloc(cf->pool, sizeof(ngx_http_v2_loc_conf_t));
    if (h2lcf == NULL) {
        return NULL;
    }

    /*
     * set by ngx_pcalloc():
     *
     *     h2lcf->pushes = NULL;
     */

    h2lcf->chunk_size = NGX_CONF_UNSET_SIZE;

    h2lcf->push_preload = NGX_CONF_UNSET;
    h2lcf->push = NGX_CONF_UNSET;

    return h2lcf;
}


static char *
ngx_http_v2_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
{
    ngx_http_v2_loc_conf_t *prev = parent;
    ngx_http_v2_loc_conf_t *conf = child;

    ngx_conf_merge_size_value(conf->chunk_size, prev->chunk_size, 8 * 1024);

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

    if (conf->push && conf->pushes == NULL) {
        conf->pushes = prev->pushes;
    }

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

    return NGX_CONF_OK;
}


static char *
ngx_http_v2_push(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_v2_loc_conf_t *h2lcf = conf;

    ngx_str_t                         *value;
    ngx_http_complex_value_t          *cv;
    ngx_http_compile_complex_value_t   ccv;

    value = cf->args->elts;

    if (ngx_strcmp(value[1].data, "off") == 0) {

        if (h2lcf->pushes) {
            return "\"off\" parameter cannot be used with URI";
        }

        if (h2lcf->push == 0) {
            return "is duplicate";
        }

        h2lcf->push = 0;
        return NGX_CONF_OK;
    }

    if (h2lcf->push == 0) {
        return "URI cannot be used with \"off\" parameter";
    }

    h2lcf->push = 1;

    if (h2lcf->pushes == NULL) {
        h2lcf->pushes = ngx_array_create(cf->pool, 1,
                                         sizeof(ngx_http_complex_value_t));
        if (h2lcf->pushes == NULL) {
            return NGX_CONF_ERROR;
        }
    }

    cv = ngx_array_push(h2lcf->pushes);
    if (cv == NULL) {
        return NGX_CONF_ERROR;
    }

    ngx_memzero(&ccv, sizeof(ngx_http_compile_complex_value_t));

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

    if (ngx_http_compile_complex_value(&ccv) != NGX_OK) {
        return NGX_CONF_ERROR;
    }

    return NGX_CONF_OK;
}


static char *
ngx_http_v2_recv_buffer_size(ngx_conf_t *cf, void *post, void *data)
{
    size_t *sp = data;

    if (*sp <= 2 * NGX_HTTP_V2_STATE_BUFFER_SIZE) {
        return "value is too small";
    }

    return NGX_CONF_OK;
}


static char *
ngx_http_v2_pool_size(ngx_conf_t *cf, void *post, void *data)
{
    size_t *sp = data;

    if (*sp < NGX_MIN_POOL_SIZE) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "the pool size must be no less than %uz",
                           NGX_MIN_POOL_SIZE);

        return NGX_CONF_ERROR;
    }

    if (*sp % NGX_POOL_ALIGNMENT) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "the pool size must be a multiple of %uz",
                           NGX_POOL_ALIGNMENT);

        return NGX_CONF_ERROR;
    }

    return NGX_CONF_OK;
}


static char *
ngx_http_v2_preread_size(ngx_conf_t *cf, void *post, void *data)
{
    size_t *sp = data;

    if (*sp > NGX_HTTP_V2_MAX_WINDOW) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "the maximum body preread buffer size is %uz",
                           NGX_HTTP_V2_MAX_WINDOW);

        return NGX_CONF_ERROR;
    }

    return NGX_CONF_OK;
}


static char *
ngx_http_v2_streams_index_mask(ngx_conf_t *cf, void *post, void *data)
{
    ngx_uint_t *np = data;

    ngx_uint_t  mask;

    mask = *np - 1;

    if (*np == 0 || (*np & mask)) {
        return "must be a power of two";
    }

    *np = mask;

    return NGX_CONF_OK;
}


static char *
ngx_http_v2_chunk_size(ngx_conf_t *cf, void *post, void *data)
{
    size_t *sp = data;

    if (*sp == 0) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "the http2 chunk size cannot be zero");

        return NGX_CONF_ERROR;
    }

    if (*sp > NGX_HTTP_V2_MAX_FRAME_SIZE) {
        *sp = NGX_HTTP_V2_MAX_FRAME_SIZE;
    }

    return NGX_CONF_OK;
}


static char *
ngx_http_v2_obsolete(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_conf_deprecated_t  *d = cmd->post;

    ngx_conf_log_error(NGX_LOG_WARN, cf, 0,
                       "the \"%s\" directive is obsolete, "
                       "use the \"%s\" directive instead",
                       d->old_name, d->new_name);

    return NGX_CONF_OK;
}