view src/http/modules/ngx_http_flv_module.c @ 7851:aa5f8825f24d

Resolver: fixed label types handling in ngx_resolver_copy(). Previously, anything with any of the two high bits set were interpreted as compression pointers. This is incorrect, as RFC 1035 clearly states that "The 10 and 01 combinations are reserved for future use". Further, the 01 combination is actually allocated for EDNS extended label type (see RFC 2671 and RFC 6891), not really used though. Fix is to reject unrecognized label types rather than misinterpreting them as compression pointers.
author Maxim Dounin <mdounin@mdounin.ru>
date Tue, 25 May 2021 15:17:41 +0300
parents 7a55311b0dc3
children 1c3b78d7cdc9
line wrap: on
line source


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

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


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

static ngx_command_t  ngx_http_flv_commands[] = {

    { ngx_string("flv"),
      NGX_HTTP_LOC_CONF|NGX_CONF_NOARGS,
      ngx_http_flv,
      0,
      0,
      NULL },

      ngx_null_command
};


static u_char  ngx_flv_header[] = "FLV\x1\x5\0\0\0\x9\0\0\0\0";


static ngx_http_module_t  ngx_http_flv_module_ctx = {
    NULL,                          /* preconfiguration */
    NULL,                          /* postconfiguration */

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

    NULL,                          /* create server configuration */
    NULL,                          /* merge server configuration */

    NULL,                          /* create location configuration */
    NULL                           /* merge location configuration */
};


ngx_module_t  ngx_http_flv_module = {
    NGX_MODULE_V1,
    &ngx_http_flv_module_ctx,      /* module context */
    ngx_http_flv_commands,         /* module directives */
    NGX_HTTP_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_int_t
ngx_http_flv_handler(ngx_http_request_t *r)
{
    u_char                    *last;
    off_t                      start, len;
    size_t                     root;
    ngx_int_t                  rc;
    ngx_uint_t                 level, i;
    ngx_str_t                  path, value;
    ngx_log_t                 *log;
    ngx_buf_t                 *b;
    ngx_chain_t                out[2];
    ngx_open_file_info_t       of;
    ngx_http_core_loc_conf_t  *clcf;

    if (!(r->method & (NGX_HTTP_GET|NGX_HTTP_HEAD))) {
        return NGX_HTTP_NOT_ALLOWED;
    }

    if (r->uri.data[r->uri.len - 1] == '/') {
        return NGX_DECLINED;
    }

    rc = ngx_http_discard_request_body(r);

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

    last = ngx_http_map_uri_to_path(r, &path, &root, 0);
    if (last == NULL) {
        return NGX_HTTP_INTERNAL_SERVER_ERROR;
    }

    log = r->connection->log;

    path.len = last - path.data;

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, log, 0,
                   "http flv filename: \"%V\"", &path);

    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);

    ngx_memzero(&of, sizeof(ngx_open_file_info_t));

    of.read_ahead = clcf->read_ahead;
    of.directio = clcf->directio;
    of.valid = clcf->open_file_cache_valid;
    of.min_uses = clcf->open_file_cache_min_uses;
    of.errors = clcf->open_file_cache_errors;
    of.events = clcf->open_file_cache_events;

    if (ngx_http_set_disable_symlinks(r, clcf, &path, &of) != NGX_OK) {
        return NGX_HTTP_INTERNAL_SERVER_ERROR;
    }

    if (ngx_open_cached_file(clcf->open_file_cache, &path, &of, r->pool)
        != NGX_OK)
    {
        switch (of.err) {

        case 0:
            return NGX_HTTP_INTERNAL_SERVER_ERROR;

        case NGX_ENOENT:
        case NGX_ENOTDIR:
        case NGX_ENAMETOOLONG:

            level = NGX_LOG_ERR;
            rc = NGX_HTTP_NOT_FOUND;
            break;

        case NGX_EACCES:
#if (NGX_HAVE_OPENAT)
        case NGX_EMLINK:
        case NGX_ELOOP:
#endif

            level = NGX_LOG_ERR;
            rc = NGX_HTTP_FORBIDDEN;
            break;

        default:

            level = NGX_LOG_CRIT;
            rc = NGX_HTTP_INTERNAL_SERVER_ERROR;
            break;
        }

        if (rc != NGX_HTTP_NOT_FOUND || clcf->log_not_found) {
            ngx_log_error(level, log, of.err,
                          "%s \"%s\" failed", of.failed, path.data);
        }

        return rc;
    }

    if (!of.is_file) {
        return NGX_DECLINED;
    }

    r->root_tested = !r->error_page;

    start = 0;
    len = of.size;
    i = 1;

    if (r->args.len) {

        if (ngx_http_arg(r, (u_char *) "start", 5, &value) == NGX_OK) {

            start = ngx_atoof(value.data, value.len);

            if (start == NGX_ERROR || start >= len) {
                start = 0;
            }

            if (start) {
                len = sizeof(ngx_flv_header) - 1 + len - start;
                i = 0;
            }
        }
    }

    log->action = "sending flv to client";

    r->headers_out.status = NGX_HTTP_OK;
    r->headers_out.content_length_n = len;
    r->headers_out.last_modified_time = of.mtime;

    if (ngx_http_set_etag(r) != NGX_OK) {
        return NGX_HTTP_INTERNAL_SERVER_ERROR;
    }

    if (ngx_http_set_content_type(r) != NGX_OK) {
        return NGX_HTTP_INTERNAL_SERVER_ERROR;
    }

    if (i == 0) {
        b = ngx_calloc_buf(r->pool);
        if (b == NULL) {
            return NGX_HTTP_INTERNAL_SERVER_ERROR;
        }

        b->pos = ngx_flv_header;
        b->last = ngx_flv_header + sizeof(ngx_flv_header) - 1;
        b->memory = 1;

        out[0].buf = b;
        out[0].next = &out[1];
    }


    b = ngx_calloc_buf(r->pool);
    if (b == NULL) {
        return NGX_HTTP_INTERNAL_SERVER_ERROR;
    }

    b->file = ngx_pcalloc(r->pool, sizeof(ngx_file_t));
    if (b->file == NULL) {
        return NGX_HTTP_INTERNAL_SERVER_ERROR;
    }

    r->allow_ranges = 1;

    rc = ngx_http_send_header(r);

    if (rc == NGX_ERROR || rc > NGX_OK || r->header_only) {
        return rc;
    }

    b->file_pos = start;
    b->file_last = of.size;

    b->in_file = b->file_last ? 1: 0;
    b->last_buf = (r == r->main) ? 1 : 0;
    b->last_in_chain = 1;

    b->file->fd = of.fd;
    b->file->name = path;
    b->file->log = log;
    b->file->directio = of.is_directio;

    out[1].buf = b;
    out[1].next = NULL;

    return ngx_http_output_filter(r, &out[i]);
}


static char *
ngx_http_flv(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_core_loc_conf_t  *clcf;

    clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module);
    clcf->handler = ngx_http_flv_handler;

    return NGX_CONF_OK;
}