nginx/SOURCES/0022-Added-max_headers-directive.patch
2026-06-24 20:12:23 -04:00

127 lines
4.9 KiB
Diff

From edb82a3e2388938f6230731e1f50e98fbde5f83f Mon Sep 17 00:00:00 2001
From: Maxim Dounin <mdounin@mdounin.ru>
Date: Fri, 24 May 2024 00:20:01 +0300
Subject: [PATCH] Added max_headers directive.
The directive limits the number of request headers accepted from clients.
While the total amount of headers is believed to be sufficiently limited
by the existing buffer size limits (client_header_buffer_size and
large_client_header_buffers), the additional limit on the number of headers
might be beneficial to better protect backend servers.
Requested by Maksim Yevmenkin.
Signed-off-by: Elijah Zupancic <e.zupancic@f5.com>
Origin: <https://freenginx.org/hg/nginx/rev/199dc0d6b05be814b5c811876c20af58cd361fea>
---
src/http/ngx_http_core_module.c | 10 ++++++++++
src/http/ngx_http_core_module.h | 2 ++
src/http/ngx_http_request.c | 9 +++++++++
src/http/ngx_http_request.h | 1 +
src/http/v2/ngx_http_v2.c | 9 +++++++++
5 files changed, 31 insertions(+)
diff --git a/src/http/ngx_http_core_module.c b/src/http/ngx_http_core_module.c
index 6664fa6..2516331 100644
--- a/src/http/ngx_http_core_module.c
+++ b/src/http/ngx_http_core_module.c
@@ -252,6 +252,13 @@ static ngx_command_t ngx_http_core_commands[] = {
offsetof(ngx_http_core_srv_conf_t, large_client_header_buffers),
NULL },
+ { ngx_string("max_headers"),
+ NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
+ ngx_conf_set_num_slot,
+ NGX_HTTP_SRV_CONF_OFFSET,
+ offsetof(ngx_http_core_srv_conf_t, max_headers),
+ NULL },
+
{ ngx_string("ignore_invalid_headers"),
NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_FLAG,
ngx_conf_set_flag_slot,
@@ -3370,6 +3377,7 @@ ngx_http_core_create_srv_conf(ngx_conf_t *cf)
cscf->request_pool_size = NGX_CONF_UNSET_SIZE;
cscf->client_header_timeout = NGX_CONF_UNSET_MSEC;
cscf->client_header_buffer_size = NGX_CONF_UNSET_SIZE;
+ cscf->max_headers = NGX_CONF_UNSET_UINT;
cscf->ignore_invalid_headers = NGX_CONF_UNSET;
cscf->merge_slashes = NGX_CONF_UNSET;
cscf->underscores_in_headers = NGX_CONF_UNSET;
@@ -3411,6 +3419,8 @@ ngx_http_core_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child)
return NGX_CONF_ERROR;
}
+ ngx_conf_merge_uint_value(conf->max_headers, prev->max_headers, 1000);
+
ngx_conf_merge_value(conf->ignore_invalid_headers,
prev->ignore_invalid_headers, 1);
diff --git a/src/http/ngx_http_core_module.h b/src/http/ngx_http_core_module.h
index 2341fd4..2e787e2 100644
--- a/src/http/ngx_http_core_module.h
+++ b/src/http/ngx_http_core_module.h
@@ -196,6 +196,8 @@ typedef struct {
ngx_msec_t client_header_timeout;
+ ngx_uint_t max_headers;
+
ngx_flag_t ignore_invalid_headers;
ngx_flag_t merge_slashes;
ngx_flag_t underscores_in_headers;
diff --git a/src/http/ngx_http_request.c b/src/http/ngx_http_request.c
index 404aa77..dccc9de 100644
--- a/src/http/ngx_http_request.c
+++ b/src/http/ngx_http_request.c
@@ -1468,6 +1468,15 @@ ngx_http_process_request_headers(ngx_event_t *rev)
/* a header line has been parsed successfully */
+ if (r->headers_in.count++ >= cscf->max_headers) {
+ r->lingering_close = 1;
+ ngx_log_error(NGX_LOG_INFO, c->log, 0,
+ "client sent too many header lines");
+ ngx_http_finalize_request(r,
+ NGX_HTTP_REQUEST_HEADER_TOO_LARGE);
+ break;
+ }
+
h = ngx_list_push(&r->headers_in.headers);
if (h == NULL) {
ngx_http_close_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
diff --git a/src/http/ngx_http_request.h b/src/http/ngx_http_request.h
index 6dfb4a4..3b46c41 100644
--- a/src/http/ngx_http_request.h
+++ b/src/http/ngx_http_request.h
@@ -180,6 +180,7 @@ typedef struct {
typedef struct {
ngx_list_t headers;
+ ngx_uint_t count;
ngx_table_elt_t *host;
ngx_table_elt_t *connection;
diff --git a/src/http/v2/ngx_http_v2.c b/src/http/v2/ngx_http_v2.c
index 291677a..7812ddc 100644
--- a/src/http/v2/ngx_http_v2.c
+++ b/src/http/v2/ngx_http_v2.c
@@ -1860,6 +1860,15 @@ ngx_http_v2_state_process_header(ngx_http_v2_connection_t *h2c, u_char *pos,
}
} else {
+ cscf = ngx_http_get_module_srv_conf(r, ngx_http_core_module);
+
+ if (r->headers_in.count++ >= cscf->max_headers) {
+ ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
+ "client sent too many header lines");
+ ngx_http_finalize_request(r, NGX_HTTP_REQUEST_HEADER_TOO_LARGE);
+ goto error;
+ }
+
h = ngx_list_push(&r->headers_in.headers);
if (h == NULL) {
return ngx_http_v2_connection_error(h2c,
--
2.44.0