Stop CSP from matching independent scheme/port upgrades

third_party/WebKit/Source/core/frame/csp/CSPSource.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/frame/csp/CSPSource.h"
 
 #include "core/frame/UseCounter.h"
 #include "core/frame/csp/ContentSecurityPolicy.h"
 #include "platform/weborigin/KURL.h"
 #include "platform/weborigin/KnownPorts.h"
@@ skipping 12 matching lines @@
     : m_policy(policy),
       m_scheme(scheme.lower()),
       m_host(host),
       m_port(port),
       m_path(path),
       m_hostWildcard(hostWildcard),
       m_portWildcard(portWildcard) {}
 
 bool CSPSource::matches(const KURL& url,
                         ResourceRequest::RedirectStatus redirectStatus) const {
-  bool schemesMatch = m_scheme.isEmpty() ? m_policy->protocolMatchesSelf(url)
-                                         : schemeMatches(url.protocol());
+  SchemeMatchingResult schemesMatch = schemeMatches(url.protocol());
   if (!schemesMatch)
     return false;
   if (isSchemeOnly())
     return true;
   bool pathsMatch = (redirectStatus == RedirectStatus::FollowedRedirect) ||
                     pathMatches(url.path());
-  return hostMatches(url.host()) && portMatches(url.port(), url.protocol()) &&
-         pathsMatch;
+  PortMatchingResult portsMatch = portMatches(url.port(), url.protocol());
+
+  // if either the scheme or the port would require an upgrade (e.g. from http
+  // to https) then check that both of them can upgrade to ensure that we don't
+  // run into situations where we only upgrade the port but not the scheme or
+  // viceversa
+  if ((requiresUpgrade(schemesMatch) || (requiresUpgrade(portsMatch))) &&
+      (!canUpgrade(schemesMatch) || !canUpgrade(portsMatch))) {
+    return false;
+  }
+
+  return hostMatches(url.host()) && portsMatch && pathsMatch;
 }
 
-bool CSPSource::schemeMatches(const String& protocol) const {
+CSPSource::SchemeMatchingResult CSPSource::schemeMatches(
+    const String& protocol) const {
   DCHECK_EQ(protocol, protocol.lower());
-  if (m_scheme == "http")
-    return protocol == "http" || protocol == "https";
-  if (m_scheme == "ws")
-    return protocol == "ws" || protocol == "wss";
-  return protocol == m_scheme;
+  const String& scheme =
+      (m_scheme.isEmpty() ? m_policy->getSelfProtocol() : m_scheme);
+
+  if (scheme == protocol)
+    return SchemeMatchingExact;
+
+  if ((scheme == "http" && protocol == "https") ||
+      (scheme == "http" && protocol == "https-so") ||
+      (scheme == "ws" && protocol == "wss")) {
+    return SchemeMatchingUpgrade;
+  }
+
+  if ((scheme == "http" && protocol == "http-so") ||
+      (scheme == "https" && protocol == "https-so")) {
+    return SchemeMatchingExact;
+  }
+
+  return SchemeNotMatching;
 }
 
 bool CSPSource::hostMatches(const String& host) const {
   Document* document = m_policy->document();
   bool match;
 
   bool equalHosts = m_host == host;
   if (m_hostWildcard == HasWildcard) {
     if (m_host.isEmpty()) {
       // host-part = "*"
@@ skipping 23 matching lines @@
     return true;
 
   String path = decodeURLEscapeSequences(urlPath);
 
   if (m_path.endsWith("/"))
     return path.startsWith(m_path);
 
   return path == m_path;
 }
 
-bool CSPSource::portMatches(int port, const String& protocol) const {
+CSPSource::PortMatchingResult CSPSource::portMatches(
+    int port,
+    const String& protocol) const {
   if (m_portWildcard == HasWildcard)
-    return true;
+    return PortMatchingWildcard;
 
-  if (port == m_port)
-    return true;
+  if (port == m_port) {
+    if (port == 0)
+      return PortMatchingWildcard;
+    return PortMatchingExact;
+  }
 
-  if (m_port == 80 &&
+  bool isSchemeHttp;  // needed for detecting an upgrade when the port is 0
+  isSchemeHttp = m_scheme.isEmpty() ? m_policy->protocolEqualsSelf("http")
+                                    : equalIgnoringCase("http", m_scheme);
+
+  if ((m_port == 80 || (m_port == 0 && isSchemeHttp)) &&
       (port == 443 || (port == 0 && defaultPortForProtocol(protocol) == 443)))
-    return true;
+    return PortMatchingUpgrade;
 
-  if (!port)
-    return isDefaultPortForProtocol(m_port, protocol);
+  if (!port) {
+    if (isDefaultPortForProtocol(m_port, protocol))
+      return PortMatchingExact;
 
-  if (!m_port)
-    return isDefaultPortForProtocol(port, protocol);
+    return PortNotMatching;
+  }
 
-  return false;
+  if (!m_port) {
+    if (isDefaultPortForProtocol(port, protocol))
+      return PortMatchingExact;
+
+    return PortNotMatching;
+  }
+
+  return PortNotMatching;
 }
 
 bool CSPSource::subsumes(CSPSource* other) const {
   if (!schemeMatches(other->m_scheme))
     return false;
 
   if (other->isSchemeOnly() || isSchemeOnly())
     return isSchemeOnly();
 
   if ((m_hostWildcard == NoWildcard && other->m_hostWildcard == HasWildcard) ||
@@ skipping 94 matching lines @@
       static_cast<WebWildcardDisposition>(m_portWildcard);
   sourceExpression.path = m_path;
   return sourceExpression;
 }
 
 DEFINE_TRACE(CSPSource) {
   visitor->trace(m_policy);
 }
 
 }  // namespace blink