Mercurial > hg > nginx
view src/http/modules/ngx_http_flv_module.c @ 7152:3b635e8fd499
FastCGI: adjust buffer position when parsing incomplete records.
Previously, nginx failed to move buffer position when parsing an incomplete
record header, and due to this wasn't be able to continue parsing once
remaining bytes of the record header were received.
This can affect response header parsing, potentially generating spurious errors
like "upstream sent unexpected FastCGI request id high byte: 1 while reading
response header from upstream". While this is very unlikely, since usually
record headers are written in a single buffer, this still can happen in real
life, for example, if a record header will be split across two TCP packets
and the second packet will be delayed.
This does not affect non-buffered response body proxying, due to "buf->pos =
buf->last;" at the start of the ngx_http_fastcgi_non_buffered_filter()
function. Also this does not affect buffered response body proxying, as
each input buffer is only passed to the filter once.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Thu, 09 Nov 2017 15:35:20 +0300 |
parents | 99934aade555 |
children | 7a55311b0dc3 |
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/* * 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) { if (ngx_close_file(of.fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_ALERT, log, ngx_errno, ngx_close_file_n " \"%s\" failed", path.data); } 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; }