// Copyright 2013 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 "extensions/common/manifest_handlers/csp_info.h"
#include "base/memory/scoped_ptr.h"
#include "base/strings/string_util.h"
#include "base/strings/utf_string_conversions.h"
#include "base/values.h"
#include "extensions/common/csp_validator.h"
#include "extensions/common/manifest_constants.h"
#include "extensions/common/manifest_handlers/sandboxed_page_info.h"
namespace extensions {
namespace keys = manifest_keys;
namespace errors = manifest_errors;
using csp_validator::ContentSecurityPolicyIsLegal;
using csp_validator::ContentSecurityPolicyIsSecure;
namespace {
const char kDefaultContentSecurityPolicy[] =
"script-src 'self' chrome-extension-resource:; object-src 'self'";
#define PLATFORM_APP_LOCAL_CSP_SOURCES \
"'self' data: chrome-extension-resource:"
const char kDefaultPlatformAppContentSecurityPolicy[] =
// Platform apps can only use local resources by default.
"default-src 'self' chrome-extension-resource:;"
// For remote resources, they can fetch them via XMLHttpRequest.
"connect-src *;"
// And serve them via data: or same-origin (blob:, filesystem:) URLs
"style-src " PLATFORM_APP_LOCAL_CSP_SOURCES " 'unsafe-inline';"
"img-src " PLATFORM_APP_LOCAL_CSP_SOURCES ";"
"frame-src " PLATFORM_APP_LOCAL_CSP_SOURCES ";"
"font-src " PLATFORM_APP_LOCAL_CSP_SOURCES ";"
// Media can be loaded from remote resources since:
// 1. <video> and <audio> have good fallback behavior when offline or under
// spotty connectivity.
// 2. Fetching via XHR and serving via blob: URLs currently does not allow
// streaming or partial buffering.
"media-src *;";
} // namespace
CSPInfo::CSPInfo(const std::string& security_policy)
: content_security_policy(security_policy) {
}
CSPInfo::~CSPInfo() {
}
// static
const std::string& CSPInfo::GetContentSecurityPolicy(
const Extension* extension) {
CSPInfo* csp_info = static_cast<CSPInfo*>(
extension->GetManifestData(keys::kContentSecurityPolicy));
return csp_info ? csp_info->content_security_policy : base::EmptyString();
}
// static
const std::string& CSPInfo::GetResourceContentSecurityPolicy(
const Extension* extension,
const std::string& relative_path) {
return SandboxedPageInfo::IsSandboxedPage(extension, relative_path) ?
SandboxedPageInfo::GetContentSecurityPolicy(extension) :
GetContentSecurityPolicy(extension);
}
CSPHandler::CSPHandler(bool is_platform_app)
: is_platform_app_(is_platform_app) {
}
CSPHandler::~CSPHandler() {
}
bool CSPHandler::Parse(Extension* extension, string16* error) {
const std::string key = Keys()[0];
if (!extension->manifest()->HasPath(key)) {
if (extension->manifest_version() >= 2) {
// TODO(abarth): Should we continue to let extensions override the
// default Content-Security-Policy?
std::string content_security_policy = is_platform_app_ ?
kDefaultPlatformAppContentSecurityPolicy :
kDefaultContentSecurityPolicy;
CHECK(ContentSecurityPolicyIsSecure(content_security_policy,
extension->GetType()));
extension->SetManifestData(keys::kContentSecurityPolicy,
new CSPInfo(content_security_policy));
}
return true;
}
std::string content_security_policy;
if (!extension->manifest()->GetString(key, &content_security_policy)) {
*error = ASCIIToUTF16(errors::kInvalidContentSecurityPolicy);
return false;
}
if (!ContentSecurityPolicyIsLegal(content_security_policy)) {
*error = ASCIIToUTF16(errors::kInvalidContentSecurityPolicy);
return false;
}
if (extension->manifest_version() >= 2 &&
!ContentSecurityPolicyIsSecure(content_security_policy,
extension->GetType())) {
*error = ASCIIToUTF16(errors::kInsecureContentSecurityPolicy);
return false;
}
extension->SetManifestData(keys::kContentSecurityPolicy,
new CSPInfo(content_security_policy));
return true;
}
bool CSPHandler::AlwaysParseForType(Manifest::Type type) const {
if (is_platform_app_)
return type == Manifest::TYPE_PLATFORM_APP;
else
return type == Manifest::TYPE_EXTENSION ||
type == Manifest::TYPE_LEGACY_PACKAGED_APP;
}
const std::vector<std::string> CSPHandler::Keys() const {
const std::string& key = is_platform_app_ ?
keys::kPlatformAppContentSecurityPolicy : keys::kContentSecurityPolicy;
return SingleKey(key);
}
} // namespace extensions