From 45e1dee27b0ba3322bf258e3f8a448dd5f7a199c Mon Sep 17 00:00:00 2001
From: Stefan Eissing <icing@apache.org>
Date: Fri, 29 Jan 2016 11:40:19 +0000
Subject: [PATCH] correctly processing multiple rel values in Link headers,
 suppressing PUSH if nopush param is present in link header

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1727545 13f79535-47bb-0310-9956-ffa450edef68
---
 CHANGES                 |  5 +++++
 modules/http2/h2_conn.c |  5 +----
 modules/http2/h2_push.c | 26 ++++++++++++++++++++++++--
 3 files changed, 30 insertions(+), 6 deletions(-)

diff --git a/CHANGES b/CHANGES
index 409be611aa..e8279021f3 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,6 +1,11 @@
                                                          -*- coding: utf-8 -*-
 Changes with Apache 2.5.0
 
+  *) mod_http2: allowing link header to specify multiple "rel" values, 
+     space-separated inside a quoted string. Prohibiting push when Link parameter
+     "nopush" is present.
+     [Stefan Eissing]
+
   *) core: Prevent a server crash in case of an invalid CONNECT request with
      a custom error page for status code 400 that uses server side includes.
      PR 58929 [Ruediger Pluem]
diff --git a/modules/http2/h2_conn.c b/modules/http2/h2_conn.c
index 747edbc7a6..29e68c11c0 100644
--- a/modules/http2/h2_conn.c
+++ b/modules/http2/h2_conn.c
@@ -311,10 +311,7 @@ struct event_conn_state_t {
     conn_rec *c;
     /** request record (if any) this struct refers to */
     request_rec *r;
-    /** is the current conn_rec suspended?  (disassociated with
-     * a particular MPM thread; for suspend_/resume_connection
-     * hooks)
-     */
+    /** server config this struct refers to */
     void *sc;
     /** is the current conn_rec suspended?  (disassociated with
      * a particular MPM thread; for suspend_/resume_connection
diff --git a/modules/http2/h2_push.c b/modules/http2/h2_push.c
index 717865c5ac..842382441e 100644
--- a/modules/http2/h2_push.c
+++ b/modules/http2/h2_push.c
@@ -282,14 +282,36 @@ static int set_header(void *ctx, const char *key, const char *value)
     return 1;
 }
 
+static int has_param(link_ctx *ctx, const char *param)
+{
+    const char *p = apr_table_get(ctx->params, param);
+    return !!p;
+}
+
+static int has_relation(link_ctx *ctx, const char *rel)
+{
+    const char *s, *val = apr_table_get(ctx->params, "rel");
+    if (val) {
+        if (!strcmp(rel, val)) {
+            return 1;
+        }
+        s = ap_strstr_c(val, rel);
+        if (s && (s == val || s[-1] == ' ')) {
+            s += strlen(rel);
+            if (!*s || *s == ' ') {
+                return 1;
+            }
+        }
+    }
+    return 0;
+}
 
 static int add_push(link_ctx *ctx)
 {
     /* so, we have read a Link header and need to decide
      * if we transform it into a push.
      */
-    const char *rel = apr_table_get(ctx->params, "rel");
-    if (rel && !strcmp("preload", rel)) {
+    if (has_relation(ctx, "preload") && !has_param(ctx, "nopush")) {
         apr_uri_t uri;
         if (apr_uri_parse(ctx->pool, ctx->link, &uri) == APR_SUCCESS) {
             if (uri.path && same_authority(ctx->req, &uri)) {
-- 
2.40.0