Mercurial > hg > nginx
view src/http/modules/ngx_http_addition_filter_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 | f583559aadc7 |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> typedef struct { ngx_str_t before_body; ngx_str_t after_body; ngx_hash_t types; ngx_array_t *types_keys; } ngx_http_addition_conf_t; typedef struct { ngx_uint_t before_body_sent; } ngx_http_addition_ctx_t; static void *ngx_http_addition_create_conf(ngx_conf_t *cf); static char *ngx_http_addition_merge_conf(ngx_conf_t *cf, void *parent, void *child); static ngx_int_t ngx_http_addition_filter_init(ngx_conf_t *cf); static ngx_command_t ngx_http_addition_commands[] = { { ngx_string("add_before_body"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_str_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_addition_conf_t, before_body), NULL }, { ngx_string("add_after_body"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_str_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_addition_conf_t, after_body), NULL }, { ngx_string("addition_types"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE, ngx_http_types_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_addition_conf_t, types_keys), &ngx_http_html_default_types[0] }, ngx_null_command }; static ngx_http_module_t ngx_http_addition_filter_module_ctx = { NULL, /* preconfiguration */ ngx_http_addition_filter_init, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ NULL, /* create server configuration */ NULL, /* merge server configuration */ ngx_http_addition_create_conf, /* create location configuration */ ngx_http_addition_merge_conf /* merge location configuration */ }; ngx_module_t ngx_http_addition_filter_module = { NGX_MODULE_V1, &ngx_http_addition_filter_module_ctx, /* module context */ ngx_http_addition_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_http_output_header_filter_pt ngx_http_next_header_filter; static ngx_http_output_body_filter_pt ngx_http_next_body_filter; static ngx_int_t ngx_http_addition_header_filter(ngx_http_request_t *r) { ngx_http_addition_ctx_t *ctx; ngx_http_addition_conf_t *conf; if (r->headers_out.status != NGX_HTTP_OK || r != r->main) { return ngx_http_next_header_filter(r); } conf = ngx_http_get_module_loc_conf(r, ngx_http_addition_filter_module); if (conf->before_body.len == 0 && conf->after_body.len == 0) { return ngx_http_next_header_filter(r); } if (ngx_http_test_content_type(r, &conf->types) == NULL) { return ngx_http_next_header_filter(r); } ctx = ngx_pcalloc(r->pool, sizeof(ngx_http_addition_ctx_t)); if (ctx == NULL) { return NGX_ERROR; } ngx_http_set_ctx(r, ctx, ngx_http_addition_filter_module); ngx_http_clear_content_length(r); ngx_http_clear_accept_ranges(r); ngx_http_weak_etag(r); r->preserve_body = 1; return ngx_http_next_header_filter(r); } static ngx_int_t ngx_http_addition_body_filter(ngx_http_request_t *r, ngx_chain_t *in) { ngx_int_t rc; ngx_uint_t last; ngx_chain_t *cl; ngx_http_request_t *sr; ngx_http_addition_ctx_t *ctx; ngx_http_addition_conf_t *conf; if (in == NULL || r->header_only) { return ngx_http_next_body_filter(r, in); } ctx = ngx_http_get_module_ctx(r, ngx_http_addition_filter_module); if (ctx == NULL) { return ngx_http_next_body_filter(r, in); } conf = ngx_http_get_module_loc_conf(r, ngx_http_addition_filter_module); if (!ctx->before_body_sent) { ctx->before_body_sent = 1; if (conf->before_body.len) { if (ngx_http_subrequest(r, &conf->before_body, NULL, &sr, NULL, 0) != NGX_OK) { return NGX_ERROR; } } } if (conf->after_body.len == 0) { ngx_http_set_ctx(r, NULL, ngx_http_addition_filter_module); return ngx_http_next_body_filter(r, in); } last = 0; for (cl = in; cl; cl = cl->next) { if (cl->buf->last_buf) { cl->buf->last_buf = 0; cl->buf->last_in_chain = 1; cl->buf->sync = 1; last = 1; } } rc = ngx_http_next_body_filter(r, in); if (rc == NGX_ERROR || !last || conf->after_body.len == 0) { return rc; } if (ngx_http_subrequest(r, &conf->after_body, NULL, &sr, NULL, 0) != NGX_OK) { return NGX_ERROR; } ngx_http_set_ctx(r, NULL, ngx_http_addition_filter_module); return ngx_http_send_special(r, NGX_HTTP_LAST); } static ngx_int_t ngx_http_addition_filter_init(ngx_conf_t *cf) { ngx_http_next_header_filter = ngx_http_top_header_filter; ngx_http_top_header_filter = ngx_http_addition_header_filter; ngx_http_next_body_filter = ngx_http_top_body_filter; ngx_http_top_body_filter = ngx_http_addition_body_filter; return NGX_OK; } static void * ngx_http_addition_create_conf(ngx_conf_t *cf) { ngx_http_addition_conf_t *conf; conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_addition_conf_t)); if (conf == NULL) { return NULL; } /* * set by ngx_pcalloc(): * * conf->before_body = { 0, NULL }; * conf->after_body = { 0, NULL }; * conf->types = { NULL }; * conf->types_keys = NULL; */ return conf; } static char * ngx_http_addition_merge_conf(ngx_conf_t *cf, void *parent, void *child) { ngx_http_addition_conf_t *prev = parent; ngx_http_addition_conf_t *conf = child; ngx_conf_merge_str_value(conf->before_body, prev->before_body, ""); ngx_conf_merge_str_value(conf->after_body, prev->after_body, ""); if (ngx_http_merge_types(cf, &conf->types_keys, &conf->types, &prev->types_keys, &prev->types, ngx_http_html_default_types) != NGX_OK) { return NGX_CONF_ERROR; } return NGX_CONF_OK; }