svn commit: r1809028 - in /httpd/httpd/trunk: CHANGES modules/mappers/mod_rewrite.c server/util_expr_eval.c

[el...@apache.org]

Author: elukey
Date: Wed Sep 20 13:03:41 2017
New Revision: 1809028

URL: http://svn.apache.org/viewvc?rev=1809028&view=rev
Log:
mod_rewrite,core: avoid Vary:Host (part 2)

This is a follow up of r1808746 after a chat
with Yann on dev@:

- the HTTP:Host variable suffers from the same problem
- the strcasecmp should be used to allow case-sensitive
  comparisons.
- in mod_rewrite is less cumbersome and more clean to just
  make the Host header check in lookup_header, so it will
  be automatically picked up by every part of the code
  that uses it. It shouldn't be a relevant overhead for
  mod_rewrite.


Modified:
    httpd/httpd/trunk/CHANGES
    httpd/httpd/trunk/modules/mappers/mod_rewrite.c
    httpd/httpd/trunk/server/util_expr_eval.c

Modified: httpd/httpd/trunk/CHANGES
URL: http://svn.apache.org/viewvc/httpd/httpd/trunk/CHANGES?rev=1809028&r1=1809027&r2=1809028&view=diff
==============================================================================
--- httpd/httpd/trunk/CHANGES [utf-8] (original)
+++ httpd/httpd/trunk/CHANGES [utf-8] Wed Sep 20 13:03:41 2017
@@ -5,7 +5,7 @@ Changes with Apache 2.5.0
      PR 38923 [Nick Kew]
 
   *) mod_rewrite, core: Avoid the 'Vary: Host' response header when HTTP_HOST is
-     used in a condition that evaluates to true. PR 58231 [Luca Toscano]
+     used in a condition that evaluates to true. PR 58231 [Luca Toscano, Yann Ylavic]
 
   *) mod_md: v0.9.6: a "MDRequireHttps permament" configured domain automatically sends out
      HSTS (rfc 6797) headers in https: responses. [Stefan Eissing]

Modified: httpd/httpd/trunk/modules/mappers/mod_rewrite.c
URL: http://svn.apache.org/viewvc/httpd/httpd/trunk/modules/mappers/mod_rewrite.c?rev=1809028&r1=1809027&r2=1809028&view=diff
==============================================================================
--- httpd/httpd/trunk/modules/mappers/mod_rewrite.c (original)
+++ httpd/httpd/trunk/modules/mappers/mod_rewrite.c Wed Sep 20 13:03:41 2017
@@ -1808,7 +1808,10 @@ static const char *lookup_header(const c
 {
     const char *val = apr_table_get(ctx->r->headers_in, name);
 
-    if (val) {
+    /* Skip the 'Vary: Host' header combination
+     * as indicated in rfc7231 section-7.1.4
+     */
+    if (val && strcasecmp(name, "Host") != 0) {
         ctx->vary_this = ctx->vary_this
                          ? apr_pstrcat(ctx->r->pool, ctx->vary_this, ", ",
                                        name, NULL)
@@ -2035,10 +2038,7 @@ static char *lookup_variable(char *var,
 
             case 'S':
                 if (!strcmp(var, "HTTP_HOST")) {
-                    /* Skip the 'Vary: Host' header combination
-                     * as indicated in rfc7231 section-7.1.4
-                     */
-                    result = apr_table_get(ctx->r->headers_in, "Host");
+                    result = lookup_header("Host", ctx);
                 }
                 break;
 

Modified: httpd/httpd/trunk/server/util_expr_eval.c
URL: http://svn.apache.org/viewvc/httpd/httpd/trunk/server/util_expr_eval.c?rev=1809028&r1=1809027&r2=1809028&view=diff
==============================================================================
--- httpd/httpd/trunk/server/util_expr_eval.c (original)
+++ httpd/httpd/trunk/server/util_expr_eval.c Wed Sep 20 13:03:41 2017
@@ -1044,7 +1044,12 @@ static const char *req_table_func(ap_exp
         t = ctx->r->headers_in;
     else {                          /* req, http */
         t = ctx->r->headers_in;
-        add_vary(ctx, arg);
+        /* Skip the 'Vary: Host' header combination
+         * as indicated in rfc7231 section-7.1.4
+         */
+        if (strcasecmp(arg, "Host")){
+            add_vary(ctx, arg);
+        }
     }
     return apr_table_get(t, arg);
 }
@@ -1609,7 +1614,7 @@ static const char *req_header_var_fn(ap_
     /* Skip the 'Vary: Host' header combination
      * as indicated in rfc7231 section-7.1.4
      */
-    if (strcmp(name, "Host")){
+    if (strcasecmp(name, "Host")){
         add_vary(ctx, name);
     }
     return apr_table_get(ctx->r->headers_in, name);