/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "nsAttrValue.h"
#include "nsCharSeparatedTokenizer.h"
#include "nsContentUtils.h"
#include "nsCSPUtils.h"
#include "nsDebug.h"
#include "nsCSPParser.h"
#include "nsComponentManagerUtils.h"
#include "nsIConsoleService.h"
#include "nsIContentSecurityPolicy.h"
#include "nsIChannel.h"
#include "nsICryptoHash.h"
#include "nsIScriptError.h"
#include "nsIStringBundle.h"
#include "nsIURL.h"
#include "nsNetUtil.h"
#include "nsReadableUtils.h"
#include "nsSandboxFlags.h"
#include "nsServiceManagerUtils.h"
#include "nsWhitespaceTokenizer.h"
#include "mozilla/Assertions.h"
#include "mozilla/Components.h"
#include "mozilla/dom/CSPDictionariesBinding.h"
#include "mozilla/dom/Document.h"
#include "mozilla/dom/SRIMetadata.h"
#include "mozilla/dom/TrustedTypesConstants.h"
#include "mozilla/StaticPrefs_security.h"
using namespace mozilla;
using mozilla::dom::SRIMetadata;
#define DEFAULT_PORT -1
static mozilla::LogModule* GetCspUtilsLog() {
static mozilla::LazyLogModule gCspUtilsPRLog(
"CSPUtils");
return gCspUtilsPRLog;
}
#define CSPUTILSLOG(args) \
MOZ_LOG(GetCspUtilsLog(), mozilla::LogLevel::Debug, args)
#define CSPUTILSLOGENABLED() \
MOZ_LOG_TEST(GetCspUtilsLog(), mozilla::LogLevel::Debug)
void CSP_PercentDecodeStr(
const nsAString& aEncStr, nsAString& outDecStr) {
outDecStr.Truncate();
// helper function that should not be visible outside this methods scope
struct local {
static inline char16_t convertHexDig(char16_t aHexDig) {
if (isNumberToken(aHexDig)) {
return aHexDig -
'0';
}
if (aHexDig >=
'A' && aHexDig <=
'F') {
return aHexDig -
'A' + 10;
}
// must be a lower case character
// (aHexDig >= 'a' && aHexDig <= 'f')
return aHexDig -
'a' + 10;
}
};
const char16_t *cur, *end, *hexDig1, *hexDig2;
cur = aEncStr.BeginReading();
end = aEncStr.EndReading();
while (cur != end) {
// if it's not a percent sign then there is
// nothing to do for that character
if (*cur != PERCENT_SIGN) {
outDecStr.Append(*cur);
cur++;
continue;
}
// get the two hexDigs following the '%'-sign
hexDig1 = cur + 1;
hexDig2 = cur + 2;
// if there are no hexdigs after the '%' then
// there is nothing to do for us.
if (hexDig1 == end || hexDig2 == end || !isValidHexDig(*hexDig1) ||
!isValidHexDig(*hexDig2)) {
outDecStr.Append(PERCENT_SIGN);
cur++;
continue;
}
// decode "% hexDig1 hexDig2" into a character.
char16_t decChar =
(local::convertHexDig(*hexDig1) << 4) + local::convertHexDig(*hexDig2);
outDecStr.Append(decChar);
// increment 'cur' to after the second hexDig
cur = ++hexDig2;
}
}
// The Content Security Policy should be inherited for
// local schemes like: "about", "blob", "data", or "filesystem".
// see: https://w3c.github.io/webappsec-csp/#initialize-document-csp
bool CSP_ShouldResponseInheritCSP(nsIChannel* aChannel) {
if (!aChannel) {
return false;
}
nsCOMPtr<nsIURI> uri;
nsresult rv = aChannel->GetURI(getter_AddRefs(uri));
NS_ENSURE_SUCCESS(rv,
false);
bool isAbout = uri->SchemeIs(
"about");
if (isAbout) {
nsAutoCString aboutSpec;
rv = uri->GetSpec(aboutSpec);
NS_ENSURE_SUCCESS(rv,
false);
// also allow about:blank#foo
if (StringBeginsWith(aboutSpec,
"about:blank"_ns) ||
StringBeginsWith(aboutSpec,
"about:srcdoc"_ns)) {
return true;
}
}
return uri->SchemeIs(
"blob") || uri->SchemeIs(
"data") ||
uri->SchemeIs(
"filesystem") || uri->SchemeIs(
"javascript");
}
void CSP_ApplyMetaCSPToDoc(mozilla::dom::Document& aDoc,
const nsAString& aPolicyStr) {
if (aDoc.IsLoadedAsData()) {
return;
}
nsAutoString policyStr(
nsContentUtils::TrimWhitespace<nsContentUtils::IsHTMLWhitespace>(
aPolicyStr));
if (policyStr.IsEmpty()) {
return;
}
nsCOMPtr<nsIContentSecurityPolicy> csp = aDoc.GetCsp();
if (!csp) {
MOZ_ASSERT(
false,
"how come there is no CSP");
return;
}
// Make the <meta> policy in browser.xhtml toggleable.
if (nsIURI* uri = aDoc.GetDocumentURI();
uri->SchemeIs(
"chrome") &&
!StaticPrefs::security_browser_xhtml_csp_enabled()) {
nsAutoCString spec;
uri->GetSpec(spec);
if (spec.EqualsLiteral(
"chrome://browser/content/browser.xhtml")) {
return;
}
}
// Multiple CSPs (delivered through either header of meta tag) need to
// be joined together, see:
// https://w3c.github.io/webappsec/specs/content-security-policy/#delivery-html-meta-element
nsresult rv =
csp->AppendPolicy(policyStr,
false,
// csp via meta tag can not be report only
true);
// delivered through the meta tag
NS_ENSURE_SUCCESS_VOID(rv);
if (nsPIDOMWindowInner* inner = aDoc.GetInnerWindow()) {
inner->SetCsp(csp);
}
aDoc.ApplySettingsFromCSP(
false);
}
void CSP_GetLocalizedStr(
const char* aName,
const nsTArray<nsString>& aParams,
nsAString& outResult) {
nsCOMPtr<nsIStringBundle> keyStringBundle;
nsCOMPtr<nsIStringBundleService> stringBundleService =
mozilla::components::StringBundle::Service();
NS_ASSERTION(stringBundleService,
"String bundle service must be present!");
stringBundleService->CreateBundle(
"chrome://global/locale/security/csp.properties",
getter_AddRefs(keyStringBundle));
NS_ASSERTION(keyStringBundle,
"Key string bundle must be available!");
if (!keyStringBundle) {
return;
}
if (aParams.IsEmpty()) {
keyStringBundle->GetStringFromName(aName, outResult);
}
else {
keyStringBundle->FormatStringFromName(aName, aParams, outResult);
}
}
void CSP_LogStrMessage(
const nsAString& aMsg) {
nsCOMPtr<nsIConsoleService> console(
do_GetService(
"@mozilla.org/consoleservice;1"));
if (!console) {
return;
}
nsString msg(aMsg);
console->LogStringMessage(msg.get());
}
void CSP_LogMessage(
const nsAString& aMessage,
const nsACString& aSourceName,
const nsAString& aSourceLine, uint32_t aLineNumber,
uint32_t aColumnNumber, uint32_t aFlags,
const nsACString& aCategory, uint64_t aInnerWindowID,
bool aFromPrivateWindow) {
nsCOMPtr<nsIConsoleService> console(
do_GetService(NS_CONSOLESERVICE_CONTRACTID));
nsCOMPtr<nsIScriptError> error(do_CreateInstance(NS_SCRIPTERROR_CONTRACTID));
if (!console || !error) {
return;
}
// Prepending CSP to the outgoing console message
nsString cspMsg;
CSP_GetLocalizedStr(
"CSPMessagePrefix",
AutoTArray<nsString, 1>{nsString(aMessage)}, cspMsg);
// Currently 'aSourceLine' is not logged to the console, because similar
// information is already included within the source link of the message.
// For inline violations however, the line and column number are 0 and
// information contained within 'aSourceLine' can be really useful for devs.
// E.g. 'aSourceLine' might be: 'onclick attribute on DIV element'.
// In such cases we append 'aSourceLine' directly to the error message.
if (!aSourceLine.IsEmpty() && aLineNumber == 0) {
cspMsg.AppendLiteral(u
"\nSource: ");
cspMsg.Append(aSourceLine);
}
// Since we are leveraging csp errors as the category names which
// we pass to devtools, we should prepend them with "CSP_" to
// allow easy distincution in devtools code. e.g.
// upgradeInsecureRequest -> CSP_upgradeInsecureRequest
nsCString category(
"CSP_");
category.Append(aCategory);
nsresult rv;
if (aInnerWindowID > 0) {
rv =
error->InitWithWindowID(cspMsg, aSourceName, aLineNumber, aColumnNumber,
aFlags, category, aInnerWindowID);
}
else {
rv = error->Init(cspMsg, aSourceName, aLineNumber, aColumnNumber, aFlags,
category, aFromPrivateWindow,
true /* from chrome context */);
}
if (NS_FAILED(rv)) {
return;
}
console->LogMessage(error);
}
CSPDirective CSP_StringToCSPDirective(
const nsAString& aDir) {
nsString lowerDir = PromiseFlatString(aDir);
ToLowerCase(lowerDir);
uint32_t numDirs = (
sizeof(CSPStrDirectives) /
sizeof(CSPStrDirectives[0]));
for (uint32_t i = 1; i < numDirs; i++) {
if (lowerDir.EqualsASCII(CSPStrDirectives[i])) {
return static_cast<CSPDirective>(i);
}
}
return nsIContentSecurityPolicy::NO_DIRECTIVE;
}
/**
* Combines CSP_LogMessage and CSP_GetLocalizedStr into one call.
*/
void CSP_LogLocalizedStr(
const char* aName,
const nsTArray<nsString>& aParams,
const nsACString& aSourceName,
const nsAString& aSourceLine, uint32_t aLineNumber,
uint32_t aColumnNumber, uint32_t aFlags,
const nsACString& aCategory, uint64_t aInnerWindowID,
bool aFromPrivateWindow) {
nsAutoString logMsg;
CSP_GetLocalizedStr(aName, aParams, logMsg);
CSP_LogMessage(logMsg, aSourceName, aSourceLine, aLineNumber, aColumnNumber,
aFlags, aCategory, aInnerWindowID, aFromPrivateWindow);
}
/* ===== Helpers ============================ */
// This implements
// https://w3c.github.io/webappsec-csp/#effective-directive-for-a-request.
// However the spec doesn't currently cover all request destinations, which
// we roughly represent using nsContentPolicyType.
CSPDirective CSP_ContentTypeToDirective(nsContentPolicyType aType) {
switch (aType) {
case nsIContentPolicy::TYPE_IMAGE:
case nsIContentPolicy::TYPE_IMAGESET:
case nsIContentPolicy::TYPE_INTERNAL_IMAGE:
case nsIContentPolicy::TYPE_INTERNAL_IMAGE_PRELOAD:
case nsIContentPolicy::TYPE_INTERNAL_IMAGE_FAVICON:
case nsIContentPolicy::TYPE_INTERNAL_EXTERNAL_RESOURCE:
return nsIContentSecurityPolicy::IMG_SRC_DIRECTIVE;
// BLock XSLT as script, see bug 910139
case nsIContentPolicy::TYPE_XSLT:
case nsIContentPolicy::TYPE_SCRIPT:
case nsIContentPolicy::TYPE_INTERNAL_SCRIPT:
case nsIContentPolicy::TYPE_INTERNAL_SCRIPT_PRELOAD:
case nsIContentPolicy::TYPE_INTERNAL_MODULE:
case nsIContentPolicy::TYPE_INTERNAL_MODULE_PRELOAD:
case nsIContentPolicy::TYPE_INTERNAL_WORKER_IMPORT_SCRIPTS:
case nsIContentPolicy::TYPE_INTERNAL_AUDIOWORKLET:
case nsIContentPolicy::TYPE_INTERNAL_PAINTWORKLET:
case nsIContentPolicy::TYPE_INTERNAL_CHROMEUTILS_COMPILED_SCRIPT:
case nsIContentPolicy::TYPE_INTERNAL_FRAME_MESSAGEMANAGER_SCRIPT:
// (https://github.com/w3c/webappsec-csp/issues/554)
// Some of these types are not explicitly defined in the spec.
//
// Chrome seems to use script-src-elem for worklet!
return nsIContentSecurityPolicy::SCRIPT_SRC_ELEM_DIRECTIVE;
case nsIContentPolicy::TYPE_STYLESHEET:
case nsIContentPolicy::TYPE_INTERNAL_STYLESHEET:
case nsIContentPolicy::TYPE_INTERNAL_STYLESHEET_PRELOAD:
return nsIContentSecurityPolicy::STYLE_SRC_ELEM_DIRECTIVE;
case nsIContentPolicy::TYPE_FONT:
case nsIContentPolicy::TYPE_INTERNAL_FONT_PRELOAD:
return nsIContentSecurityPolicy::FONT_SRC_DIRECTIVE;
case nsIContentPolicy::TYPE_MEDIA:
case nsIContentPolicy::TYPE_INTERNAL_AUDIO:
case nsIContentPolicy::TYPE_INTERNAL_VIDEO:
case nsIContentPolicy::TYPE_INTERNAL_TRACK:
return nsIContentSecurityPolicy::MEDIA_SRC_DIRECTIVE;
case nsIContentPolicy::TYPE_WEB_MANIFEST:
return nsIContentSecurityPolicy::WEB_MANIFEST_SRC_DIRECTIVE;
case nsIContentPolicy::TYPE_INTERNAL_WORKER:
case nsIContentPolicy::TYPE_INTERNAL_WORKER_STATIC_MODULE:
case nsIContentPolicy::TYPE_INTERNAL_SHARED_WORKER:
case nsIContentPolicy::TYPE_INTERNAL_SERVICE_WORKER:
return nsIContentSecurityPolicy::WORKER_SRC_DIRECTIVE;
case nsIContentPolicy::TYPE_SUBDOCUMENT:
case nsIContentPolicy::TYPE_INTERNAL_FRAME:
case nsIContentPolicy::TYPE_INTERNAL_IFRAME:
return nsIContentSecurityPolicy::FRAME_SRC_DIRECTIVE;
case nsIContentPolicy::TYPE_WEBSOCKET:
case nsIContentPolicy::TYPE_XMLHTTPREQUEST:
case nsIContentPolicy::TYPE_BEACON:
case nsIContentPolicy::TYPE_PING:
case nsIContentPolicy::TYPE_FETCH:
case nsIContentPolicy::TYPE_INTERNAL_XMLHTTPREQUEST_ASYNC:
case nsIContentPolicy::TYPE_INTERNAL_XMLHTTPREQUEST_SYNC:
case nsIContentPolicy::TYPE_INTERNAL_EVENTSOURCE:
case nsIContentPolicy::TYPE_INTERNAL_FETCH_PRELOAD:
case nsIContentPolicy::TYPE_WEB_IDENTITY:
case nsIContentPolicy::TYPE_WEB_TRANSPORT:
case nsIContentPolicy::TYPE_JSON:
case nsIContentPolicy::TYPE_INTERNAL_JSON_PRELOAD:
return nsIContentSecurityPolicy::CONNECT_SRC_DIRECTIVE;
case nsIContentPolicy::TYPE_OBJECT:
case nsIContentPolicy::TYPE_OBJECT_SUBREQUEST:
case nsIContentPolicy::TYPE_INTERNAL_EMBED:
case nsIContentPolicy::TYPE_INTERNAL_OBJECT:
return nsIContentSecurityPolicy::OBJECT_SRC_DIRECTIVE;
case nsIContentPolicy::TYPE_DTD:
case nsIContentPolicy::TYPE_OTHER:
case nsIContentPolicy::TYPE_SPECULATIVE:
case nsIContentPolicy::TYPE_INTERNAL_DTD:
case nsIContentPolicy::TYPE_INTERNAL_FORCE_ALLOWED_DTD:
return nsIContentSecurityPolicy::DEFAULT_SRC_DIRECTIVE;
// CSP does not apply to webrtc connections
case nsIContentPolicy::TYPE_PROXIED_WEBRTC_MEDIA:
// csp shold not block top level loads, e.g. in case
// of a redirect.
case nsIContentPolicy::TYPE_DOCUMENT:
// CSP can not block csp reports
case nsIContentPolicy::TYPE_CSP_REPORT:
return nsIContentSecurityPolicy::NO_DIRECTIVE;
case nsIContentPolicy::TYPE_SAVEAS_DOWNLOAD:
case nsIContentPolicy::TYPE_UA_FONT:
return nsIContentSecurityPolicy::NO_DIRECTIVE;
// Fall through to error for all other directives
case nsIContentPolicy::TYPE_INVALID:
case nsIContentPolicy::TYPE_END:
MOZ_ASSERT(
false,
"Can not map nsContentPolicyType to CSPDirective");
// Do not add default: so that compilers can catch the missing case.
}
return nsIContentSecurityPolicy::DEFAULT_SRC_DIRECTIVE;
}
nsCSPHostSrc* CSP_CreateHostSrcFromSelfURI(nsIURI* aSelfURI) {
// Create the host first
nsCString host;
aSelfURI->GetAsciiHost(host);
nsCSPHostSrc* hostsrc =
new nsCSPHostSrc(NS_ConvertUTF8toUTF16(host));
hostsrc->setGeneratedFromSelfKeyword();
// Add the scheme.
nsCString scheme;
aSelfURI->GetScheme(scheme);
hostsrc->setScheme(NS_ConvertUTF8toUTF16(scheme));
// An empty host (e.g. for data:) indicates it's effectively a unique origin.
// Please note that we still need to set the scheme on hostsrc (see above),
// because it's used for reporting.
if (host.EqualsLiteral(
"")) {
hostsrc->setIsUniqueOrigin();
// no need to query the port in that case.
return hostsrc;
}
int32_t port;
aSelfURI->GetPort(&port);
// Only add port if it's not default port.
if (port > 0) {
nsAutoString portStr;
portStr.AppendInt(port);
hostsrc->setPort(portStr);
}
return hostsrc;
}
bool CSP_IsEmptyDirective(
const nsAString& aValue,
const nsAString& aDir) {
return (aDir.Length() == 0 && aValue.Length() == 0);
}
bool CSP_IsDirective(
const nsAString& aValue, CSPDirective aDir) {
return aValue.LowerCaseEqualsASCII(CSP_CSPDirectiveToString(aDir));
}
bool CSP_IsKeyword(
const nsAString& aValue,
enum CSPKeyword aKey) {
return aValue.LowerCaseEqualsASCII(CSP_EnumToUTF8Keyword(aKey));
}
bool CSP_IsQuotelessKeyword(
const nsAString& aKey) {
nsString lowerKey;
ToLowerCase(aKey, lowerKey);
nsAutoString keyword;
for (uint32_t i = 0; i < CSP_LAST_KEYWORD_VALUE; i++) {
// skipping the leading ' and trimming the trailing '
keyword.AssignASCII(gCSPUTF8Keywords[i] + 1);
keyword.Trim(
"'",
false,
true);
if (lowerKey.Equals(keyword)) {
return true;
}
}
return false;
}
/*
* Checks whether the current directive permits a specific
* scheme. This function is called from nsCSPSchemeSrc() and
* also nsCSPHostSrc.
* @param aEnforcementScheme
* The scheme that this directive allows
* @param aUri
* The uri of the subresource load.
* @param aReportOnly
* Whether the enforced policy is report only or not.
* @param aUpgradeInsecure
* Whether the policy makes use of the directive
* 'upgrade-insecure-requests'.
* @param aFromSelfURI
* Whether a scheme was generated from the keyword 'self'
* which then allows schemeless sources to match ws and wss.
*/
bool permitsScheme(
const nsAString& aEnforcementScheme, nsIURI* aUri,
bool aReportOnly,
bool aUpgradeInsecure,
bool aFromSelfURI) {
nsAutoCString scheme;
nsresult rv = aUri->GetScheme(scheme);
NS_ENSURE_SUCCESS(rv,
false);
// no scheme to enforce, let's allow the load (e.g. script-src *)
if (aEnforcementScheme.IsEmpty()) {
return true;
}
// if the scheme matches, all good - allow the load
if (aEnforcementScheme.EqualsASCII(scheme.get())) {
return true;
}
// allow scheme-less sources where the protected resource is http
// and the load is https, see:
// http://www.w3.org/TR/CSP2/#match-source-expression
if (aEnforcementScheme.EqualsASCII(
"http")) {
if (scheme.EqualsASCII(
"https")) {
return true;
}
if ((scheme.EqualsASCII(
"ws") || scheme.EqualsASCII(
"wss")) &&
aFromSelfURI) {
return true;
}
}
if (aEnforcementScheme.EqualsASCII(
"https")) {
if (scheme.EqualsLiteral(
"wss") && aFromSelfURI) {
return true;
}
}
if (aEnforcementScheme.EqualsASCII(
"ws") && scheme.EqualsASCII(
"wss")) {
return true;
}
// Allow the load when enforcing upgrade-insecure-requests with the
// promise the request gets upgraded from http to https and ws to wss.
// See nsHttpChannel::Connect() and also WebSocket.cpp. Please note,
// the report only policies should not allow the load and report
// the error back to the page.
return (
(aUpgradeInsecure && !aReportOnly) &&
((scheme.EqualsASCII(
"http") &&
aEnforcementScheme.EqualsASCII(
"https")) ||
(scheme.EqualsASCII(
"ws") && aEnforcementScheme.EqualsASCII(
"wss"))));
}
/*
* A helper function for appending a CSP header to an existing CSP
* policy.
*
* @param aCsp the CSP policy
* @param aHeaderValue the header
* @param aReportOnly is this a report-only header?
*/
nsresult CSP_AppendCSPFromHeader(nsIContentSecurityPolicy* aCsp,
const nsAString& aHeaderValue,
bool aReportOnly) {
NS_ENSURE_ARG(aCsp);
// Need to tokenize the header value since multiple headers could be
// concatenated into one comma-separated list of policies.
// See RFC2616 section 4.2 (last paragraph)
nsresult rv = NS_OK;
for (
const nsAString& policy :
nsCharSeparatedTokenizer(aHeaderValue,
',').ToRange()) {
rv = aCsp->AppendPolicy(policy, aReportOnly,
false);
NS_ENSURE_SUCCESS(rv, rv);
{
CSPUTILSLOG((
"CSP refined with policy: \"%s\
"",
NS_ConvertUTF16toUTF8(policy).get()));
}
}
return NS_OK;
}
/* ===== nsCSPSrc ============================ */
nsCSPBaseSrc::nsCSPBaseSrc() {}
nsCSPBaseSrc::~nsCSPBaseSrc() =
default;
// ::permits is only called for external load requests, therefore:
// nsCSPKeywordSrc and nsCSPHashSource fall back to this base class
// implementation which will never allow the load.
bool nsCSPBaseSrc::permits(nsIURI* aUri,
bool aWasRedirected,
bool aReportOnly,
bool aUpgradeInsecure)
const {
if (CSPUTILSLOGENABLED()) {
CSPUTILSLOG(
(
"nsCSPBaseSrc::permits, aUri: %s", aUri->GetSpecOrDefault().get()));
}
return false;
}
// ::allows is only called for inlined loads, therefore:
// nsCSPSchemeSrc, nsCSPHostSrc fall back
// to this base class implementation which will never allow the load.
bool nsCSPBaseSrc::allows(
enum CSPKeyword aKeyword,
const nsAString& aHashOrNonce)
const {
CSPUTILSLOG((
"nsCSPBaseSrc::allows, aKeyWord: %s, a HashOrNonce: %s",
aKeyword == CSP_HASH ?
"hash" : CSP_EnumToUTF8Keyword(aKeyword),
NS_ConvertUTF16toUTF8(aHashOrNonce).get()));
return false;
}
/* ====== nsCSPSchemeSrc ===================== */
nsCSPSchemeSrc::nsCSPSchemeSrc(
const nsAString& aScheme) : mScheme(aScheme) {
ToLowerCase(mScheme);
}
nsCSPSchemeSrc::~nsCSPSchemeSrc() =
default;
bool nsCSPSchemeSrc::permits(nsIURI* aUri,
bool aWasRedirected,
bool aReportOnly,
bool aUpgradeInsecure)
const {
if (CSPUTILSLOGENABLED()) {
CSPUTILSLOG(
(
"nsCSPSchemeSrc::permits, aUri: %s", aUri->GetSpecOrDefault().get()));
}
MOZ_ASSERT((!mScheme.EqualsASCII(
"")),
"scheme can not be the empty string");
return permitsScheme(mScheme, aUri, aReportOnly, aUpgradeInsecure,
false);
}
bool nsCSPSchemeSrc::visit(nsCSPSrcVisitor* aVisitor)
const {
return aVisitor->visitSchemeSrc(*
this);
}
void nsCSPSchemeSrc::toString(nsAString& outStr)
const {
outStr.Append(mScheme);
outStr.AppendLiteral(
":");
}
/* ===== nsCSPHostSrc ======================== */
nsCSPHostSrc::nsCSPHostSrc(
const nsAString& aHost)
: mHost(aHost),
mGeneratedFromSelfKeyword(
false),
mIsUniqueOrigin(
false),
mWithinFrameAncstorsDir(
false) {
ToLowerCase(mHost);
}
nsCSPHostSrc::~nsCSPHostSrc() =
default;
/*
* Checks whether the current directive permits a specific port.
* @param aEnforcementScheme
* The scheme that this directive allows
* (used to query the default port for that scheme)
* @param aEnforcementPort
* The port that this directive allows
* @param aResourceURI
* The uri of the subresource load
*/
bool permitsPort(
const nsAString& aEnforcementScheme,
const nsAString& aEnforcementPort, nsIURI* aResourceURI) {
// If enforcement port is the wildcard, don't block the load.
if (aEnforcementPort.EqualsASCII(
"*")) {
return true;
}
int32_t resourcePort;
nsresult rv = aResourceURI->GetPort(&resourcePort);
if (NS_FAILED(rv) && aEnforcementPort.IsEmpty()) {
// If we cannot get a Port (e.g. because of an Custom Protocol handler)
// We need to check if a default port is associated with the Scheme
if (aEnforcementScheme.IsEmpty()) {
return false;
}
int defaultPortforScheme =
NS_GetDefaultPort(NS_ConvertUTF16toUTF8(aEnforcementScheme).get());
// If there is no default port associated with the Scheme (
// defaultPortforScheme == -1) or it is an externally handled protocol (
// defaultPortforScheme == 0 ) and the csp does not enforce a port - we can
// allow not having a port
return (defaultPortforScheme == -1 || defaultPortforScheme == -0);
}
// Avoid unnecessary string creation/manipulation and don't block the
// load if the resource to be loaded uses the default port for that
// scheme and there is no port to be enforced.
// Note, this optimization relies on scheme checks within permitsScheme().
if (resourcePort == DEFAULT_PORT && aEnforcementPort.IsEmpty()) {
return true;
}
// By now we know at that either the resourcePort does not use the default
// port or there is a port restriction to be enforced. A port value of -1
// corresponds to the protocol's default port (eg. -1 implies port 80 for
// http URIs), in such a case we have to query the default port of the
// resource to be loaded.
if (resourcePort == DEFAULT_PORT) {
nsAutoCString resourceScheme;
rv = aResourceURI->GetScheme(resourceScheme);
NS_ENSURE_SUCCESS(rv,
false);
resourcePort = NS_GetDefaultPort(resourceScheme.get());
}
// If there is a port to be enforced and the ports match, then
// don't block the load.
nsString resourcePortStr;
resourcePortStr.AppendInt(resourcePort);
if (aEnforcementPort.Equals(resourcePortStr)) {
return true;
}
// If there is no port to be enforced, query the default port for the load.
nsString enforcementPort(aEnforcementPort);
if (enforcementPort.IsEmpty()) {
// For scheme less sources, our parser always generates a scheme
// which is the scheme of the protected resource.
MOZ_ASSERT(!aEnforcementScheme.IsEmpty(),
"need a scheme to query default port");
int32_t defaultEnforcementPort =
NS_GetDefaultPort(NS_ConvertUTF16toUTF8(aEnforcementScheme).get());
enforcementPort.Truncate();
enforcementPort.AppendInt(defaultEnforcementPort);
}
// If default ports match, don't block the load
if (enforcementPort.Equals(resourcePortStr)) {
return true;
}
// Additional port matching where the regular URL matching algorithm
// treats insecure ports as matching their secure variants.
// default port for http is :80
// default port for https is :443
if (enforcementPort.EqualsLiteral(
"80") &&
resourcePortStr.EqualsLiteral(
"443")) {
return true;
}
// ports do not match, block the load.
return false;
}
bool nsCSPHostSrc::permits(nsIURI* aUri,
bool aWasRedirected,
bool aReportOnly,
bool aUpgradeInsecure)
const {
if (CSPUTILSLOGENABLED()) {
CSPUTILSLOG(
(
"nsCSPHostSrc::permits, aUri: %s", aUri->GetSpecOrDefault().get()));
}
if (mIsUniqueOrigin) {
return false;
}
// we are following the enforcement rules from the spec, see:
// http://www.w3.org/TR/CSP11/#match-source-expression
// 4.3) scheme matching: Check if the scheme matches.
if (!permitsScheme(mScheme, aUri, aReportOnly, aUpgradeInsecure,
mGeneratedFromSelfKeyword)) {
return false;
}
// The host in nsCSpHostSrc should never be empty. In case we are enforcing
// just a specific scheme, the parser should generate a nsCSPSchemeSource.
NS_ASSERTION((!mHost.IsEmpty()),
"host can not be the empty string");
// Before we can check if the host matches, we have to
// extract the host part from aUri.
nsAutoCString uriHost;
nsresult rv = aUri->GetAsciiHost(uriHost);
NS_ENSURE_SUCCESS(rv,
false);
nsString decodedUriHost;
CSP_PercentDecodeStr(NS_ConvertUTF8toUTF16(uriHost), decodedUriHost);
// 2) host matching: Enforce a single *
if (mHost.EqualsASCII(
"*")) {
// The single ASTERISK character (*) does not match a URI's scheme of a type
// designating a globally unique identifier (such as blob:, data:, or
// filesystem:) At the moment firefox does not support filesystem; but for
// future compatibility we support it in CSP according to the spec,
// see: 4.2.2 Matching Source Expressions Note, that allowlisting any of
// these schemes would call nsCSPSchemeSrc::permits().
if (aUri->SchemeIs(
"blob") || aUri->SchemeIs(
"data") ||
aUri->SchemeIs(
"filesystem")) {
return false;
}
// If no scheme is present there also wont be a port and folder to check
// which means we can return early
if (mScheme.IsEmpty()) {
return true;
}
}
// 4.5) host matching: Check if the allowed host starts with a wilcard.
else if (mHost.First() ==
'*') {
NS_ASSERTION(
mHost[1] ==
'.',
"Second character needs to be '.' whenever host starts with '*'");
// Eliminate leading "*", but keeping the FULL STOP (.) thereafter before
// checking if the remaining characters match
nsString wildCardHost = mHost;
wildCardHost = Substring(wildCardHost, 1, wildCardHost.Length() - 1);
if (!StringEndsWith(decodedUriHost, wildCardHost)) {
return false;
}
}
// 4.6) host matching: Check if hosts match.
else if (!mHost.Equals(decodedUriHost)) {
return false;
}
// Port matching: Check if the ports match.
if (!permitsPort(mScheme, mPort, aUri)) {
return false;
}
// 4.9) Path matching: If there is a path, we have to enforce
// path-level matching, unless the channel got redirected, see:
// http://www.w3.org/TR/CSP11/#source-list-paths-and-redirects
if (!aWasRedirected && !mPath.IsEmpty()) {
// converting aUri into nsIURL so we can strip query and ref
// example.com/test#foo -> example.com/test
// example.com/test?val=foo -> example.com/test
nsCOMPtr<nsIURL> url = do_QueryInterface(aUri);
if (!url) {
NS_ASSERTION(
false,
"can't QI into nsIURI");
return false;
}
nsAutoCString uriPath;
rv = url->GetFilePath(uriPath);
NS_ENSURE_SUCCESS(rv,
false);
if (mWithinFrameAncstorsDir) {
// no path matching for frame-ancestors to not leak any path information.
return true;
}
nsString decodedUriPath;
CSP_PercentDecodeStr(NS_ConvertUTF8toUTF16(uriPath), decodedUriPath);
// check if the last character of mPath is '/'; if so
// we just have to check loading resource is within
// the allowed path.
if (mPath.Last() ==
'/') {
if (!StringBeginsWith(decodedUriPath, mPath)) {
return false;
}
}
// otherwise mPath refers to a specific file, and we have to
// check if the loading resource matches the file.
else {
if (!mPath.Equals(decodedUriPath)) {
return false;
}
}
}
// At the end: scheme, host, port and path match -> allow the load.
return true;
}
bool nsCSPHostSrc::visit(nsCSPSrcVisitor* aVisitor)
const {
return aVisitor->visitHostSrc(*
this);
}
void nsCSPHostSrc::toString(nsAString& outStr)
const {
if (mGeneratedFromSelfKeyword) {
outStr.AppendLiteral(
"'self'");
return;
}
// If mHost is a single "*", we append the wildcard and return.
if (mHost.EqualsASCII(
"*") && mScheme.IsEmpty() && mPort.IsEmpty()) {
outStr.Append(mHost);
return;
}
// append scheme
outStr.Append(mScheme);
// append host
outStr.AppendLiteral(
"://");
outStr.Append(mHost);
// append port
if (!mPort.IsEmpty()) {
outStr.AppendLiteral(
":");
outStr.Append(mPort);
}
// append path
outStr.Append(mPath);
}
void nsCSPHostSrc::setScheme(
const nsAString& aScheme) {
mScheme = aScheme;
ToLowerCase(mScheme);
}
void nsCSPHostSrc::setPort(
const nsAString& aPort) { mPort = aPort; }
void nsCSPHostSrc::appendPath(
const nsAString& aPath) { mPath.Append(aPath); }
/* ===== nsCSPKeywordSrc ===================== */
nsCSPKeywordSrc::nsCSPKeywordSrc(
enum CSPKeyword aKeyword)
: mKeyword(aKeyword) {
NS_ASSERTION((aKeyword != CSP_SELF),
"'self' should have been replaced in the parser");
}
nsCSPKeywordSrc::~nsCSPKeywordSrc() =
default;
bool nsCSPKeywordSrc::allows(
enum CSPKeyword aKeyword,
const nsAString& aHashOrNonce)
const {
CSPUTILSLOG((
"nsCSPKeywordSrc::allows, aKeyWord: %s, aHashOrNonce: %s",
CSP_EnumToUTF8Keyword(aKeyword),
NS_ConvertUTF16toUTF8(aHashOrNonce).get()));
return mKeyword == aKeyword;
}
bool nsCSPKeywordSrc::visit(nsCSPSrcVisitor* aVisitor)
const {
return aVisitor->visitKeywordSrc(*
this);
}
void nsCSPKeywordSrc::toString(nsAString& outStr)
const {
outStr.Append(CSP_EnumToUTF16Keyword(mKeyword));
}
/* ===== nsCSPNonceSrc ==================== */
nsCSPNonceSrc::nsCSPNonceSrc(
const nsAString& aNonce) : mNonce(aNonce) {}
nsCSPNonceSrc::~nsCSPNonceSrc() =
default;
bool nsCSPNonceSrc::allows(
enum CSPKeyword aKeyword,
const nsAString& aHashOrNonce)
const {
CSPUTILSLOG((
"nsCSPNonceSrc::allows, aKeyWord: %s, a HashOrNonce: %s",
CSP_EnumToUTF8Keyword(aKeyword),
NS_ConvertUTF16toUTF8(aHashOrNonce).get()));
if (aKeyword != CSP_NONCE) {
return false;
}
// nonces can not be invalidated by strict-dynamic
return mNonce.Equals(aHashOrNonce);
}
bool nsCSPNonceSrc::visit(nsCSPSrcVisitor* aVisitor)
const {
return aVisitor->visitNonceSrc(*
this);
}
void nsCSPNonceSrc::toString(nsAString& outStr)
const {
outStr.Append(CSP_EnumToUTF16Keyword(CSP_NONCE));
outStr.Append(mNonce);
outStr.AppendLiteral(
"'");
}
/* ===== nsCSPHashSrc ===================== */
nsCSPHashSrc::nsCSPHashSrc(
const nsAString& aAlgo,
const nsAString& aHash)
: mAlgorithm(aAlgo), mHash(aHash) {
// Only the algo should be rewritten to lowercase, the hash must remain the
// same.
ToLowerCase(mAlgorithm);
// Normalize the base64url encoding to base64 encoding:
char16_t* cur = mHash.BeginWriting();
char16_t* end = mHash.EndWriting();
for (; cur < end; ++cur) {
if (char16_t(
'-') == *cur) {
*cur = char16_t(
'+');
}
if (char16_t(
'_') == *cur) {
*cur = char16_t(
'/');
}
}
}
nsCSPHashSrc::~nsCSPHashSrc() =
default;
bool nsCSPHashSrc::allows(
enum CSPKeyword aKeyword,
const nsAString& aHashOrNonce)
const {
CSPUTILSLOG((
"nsCSPHashSrc::allows, aKeyWord: %s, a HashOrNonce: %s",
CSP_EnumToUTF8Keyword(aKeyword),
NS_ConvertUTF16toUTF8(aHashOrNonce).get()));
if (aKeyword != CSP_HASH) {
return false;
}
// hashes can not be invalidated by strict-dynamic
// Convert aHashOrNonce to UTF-8
NS_ConvertUTF16toUTF8 utf8_hash(aHashOrNonce);
nsCOMPtr<nsICryptoHash> hasher;
nsresult rv = NS_NewCryptoHash(NS_ConvertUTF16toUTF8(mAlgorithm),
getter_AddRefs(hasher));
NS_ENSURE_SUCCESS(rv,
false);
rv = hasher->Update((uint8_t*)utf8_hash.get(), utf8_hash.Length());
NS_ENSURE_SUCCESS(rv,
false);
nsAutoCString hash;
rv = hasher->Finish(
true, hash);
NS_ENSURE_SUCCESS(rv,
false);
return NS_ConvertUTF16toUTF8(mHash).Equals(hash);
}
bool nsCSPHashSrc::visit(nsCSPSrcVisitor* aVisitor)
const {
return aVisitor->visitHashSrc(*
this);
}
void nsCSPHashSrc::toString(nsAString& outStr)
const {
outStr.AppendLiteral(
"'");
outStr.Append(mAlgorithm);
outStr.AppendLiteral(
"-");
outStr.Append(mHash);
outStr.AppendLiteral(
"'");
}
/* ===== nsCSPReportURI ===================== */
nsCSPReportURI::nsCSPReportURI(nsIURI* aURI) : mReportURI(aURI) {}
nsCSPReportURI::~nsCSPReportURI() =
default;
bool nsCSPReportURI::visit(nsCSPSrcVisitor* aVisitor)
const {
return false; }
void nsCSPReportURI::toString(nsAString& outStr)
const {
nsAutoCString spec;
nsresult rv = mReportURI->GetSpec(spec);
if (NS_FAILED(rv)) {
return;
}
outStr.AppendASCII(spec.get());
}
/* ===== nsCSPReportGroup ===================== */
nsCSPGroup::nsCSPGroup(
const nsAString& aGroup) : mGroup(aGroup) {}
nsCSPGroup::~nsCSPGroup() =
default;
bool nsCSPGroup::visit(nsCSPSrcVisitor* aVisitor)
const {
return false; }
void nsCSPGroup::toString(nsAString& aOutStr)
const { aOutStr.Append(mGroup); }
/* ===== nsCSPSandboxFlags ===================== */
nsCSPSandboxFlags::nsCSPSandboxFlags(
const nsAString& aFlags) : mFlags(aFlags) {
ToLowerCase(mFlags);
}
nsCSPSandboxFlags::~nsCSPSandboxFlags() =
default;
bool nsCSPSandboxFlags::visit(nsCSPSrcVisitor* aVisitor)
const {
return false; }
void nsCSPSandboxFlags::toString(nsAString& outStr)
const {
outStr.Append(mFlags);
}
/* ===== nsCSPRequireTrustedTypesForDirectiveValue ===================== */
nsCSPRequireTrustedTypesForDirectiveValue::
nsCSPRequireTrustedTypesForDirectiveValue(
const nsAString& aValue)
: mValue{aValue} {}
bool nsCSPRequireTrustedTypesForDirectiveValue::visit(
nsCSPSrcVisitor* aVisitor)
const {
MOZ_ASSERT_UNREACHABLE(
"This method should only be called for other overloads of this method.");
return false;
}
void nsCSPRequireTrustedTypesForDirectiveValue::toString(
nsAString& aOutStr)
const {
aOutStr.Append(mValue);
}
/* =============== nsCSPTrustedTypesDirectivePolicyName =============== */
nsCSPTrustedTypesDirectivePolicyName::nsCSPTrustedTypesDirectivePolicyName(
const nsAString& aName)
: mName{aName} {}
bool nsCSPTrustedTypesDirectivePolicyName::visit(
nsCSPSrcVisitor* aVisitor)
const {
MOZ_ASSERT_UNREACHABLE(
"Should only be called for other overloads of this method.");
return false;
}
void nsCSPTrustedTypesDirectivePolicyName::toString(nsAString& aOutStr)
const {
aOutStr.Append(mName);
}
/* ===== nsCSPDirective ====================== */
nsCSPDirective::nsCSPDirective(CSPDirective aDirective) {
mDirective = aDirective;
}
nsCSPDirective::~nsCSPDirective() {
for (uint32_t i = 0; i < mSrcs.Length(); i++) {
delete mSrcs[i];
}
}
// https://w3c.github.io/webappsec-csp/#match-nonce-to-source-list
static bool DoesNonceMatchSourceList(nsILoadInfo* aLoadInfo,
const nsTArray<nsCSPBaseSrc*>& aSrcs) {
// Step 1. Assert: source list is not null. (implicit)
// Note: For code-reuse we do "request’s cryptographic nonce metadata" here
// instead of the caller.
nsAutoString nonce;
MOZ_ALWAYS_SUCCEEDS(aLoadInfo->GetCspNonce(nonce));
// Step 2. If nonce is the empty string, return "Does Not Match".
if (nonce.IsEmpty()) {
return false;
}
// Step 3. For each expression of source list:
for (nsCSPBaseSrc* src : aSrcs) {
// Step 3.1. If expression matches the nonce-source grammar, and nonce is
// identical to expression’s base64-value part, return "Matches".
if (src->isNonce()) {
nsAutoString srcNonce;
static_cast<nsCSPNonceSrc*>(src)->getNonce(srcNonce);
if (srcNonce == nonce) {
return true;
}
}
}
// Step 4. Return "Does Not Match".
return false;
}
// https://www.w3.org/TR/SRI/#parse-metadata
// This function is similar to SRICheck::IntegrityMetadata, but also keeps
// SRI metadata with weaker hashes.
// CSP treats "no metadata" and empty results the same way.
static nsTArray<SRIMetadata> ParseSRIMetadata(
const nsAString& aMetadata) {
// Step 1. Let result be the empty set.
// Step 2. Let empty be equal to true.
nsTArray<SRIMetadata> result;
NS_ConvertUTF16toUTF8 metadataList(aMetadata);
nsAutoCString token;
// Step 3. For each token returned by splitting metadata on spaces:
nsCWhitespaceTokenizer tokenizer(metadataList);
while (tokenizer.hasMoreTokens()) {
token = tokenizer.nextToken();
// Step 3.1. Set empty to false.
// Step 3.3. Parse token per the grammar in integrity metadata.
SRIMetadata metadata(token);
// Step 3.2. If token is not a valid metadata, skip the remaining steps, and
// proceed to the next token.
if (metadata.IsMalformed()) {
continue;
}
// Step 3.4. Let algorithm be the alg component of token.
// Step 3.5. If algorithm is a hash function recognized by the user agent,
// add the
// parsed token to result.
if (metadata.IsAlgorithmSupported()) {
result.AppendElement(metadata);
}
}
// Step 4. Return no metadata if empty is true, otherwise return result.
return result;
}
bool nsCSPDirective::permits(CSPDirective aDirective, nsILoadInfo* aLoadInfo,
nsIURI* aUri,
bool aWasRedirected,
bool aReportOnly,
bool aUpgradeInsecure)
const {
MOZ_ASSERT(equals(aDirective) || isDefaultDirective());
if (CSPUTILSLOGENABLED()) {
CSPUTILSLOG((
"nsCSPDirective::permits, aUri: %s, aDirective: %s",
aUri->GetSpecOrDefault().get(),
CSP_CSPDirectiveToString(aDirective)));
}
if (aLoadInfo) {
// https://w3c.github.io/webappsec-csp/#style-src-elem-pre-request
if (aDirective == CSPDirective::STYLE_SRC_ELEM_DIRECTIVE) {
// Step 3. If the result of executing §6.7.2.3 Does nonce match source
// list? on request’s cryptographic nonce metadata and this directive’s
// value is "Matches", return "Allowed".
if (DoesNonceMatchSourceList(aLoadInfo, mSrcs)) {
CSPUTILSLOG((
" Allowed by matching nonce (style)"));
return true;
}
}
// https://w3c.github.io/webappsec-csp/#script-pre-request
// Step 1. If request’s destination is script-like:
else if (aDirective == CSPDirective::SCRIPT_SRC_ELEM_DIRECTIVE ||
aDirective == CSPDirective::WORKER_SRC_DIRECTIVE) {
// Step 1.1. If the result of executing §6.7.2.3 Does nonce match source
// list? on request’s cryptographic nonce metadata and this directive’s
// value is "Matches", return "Allowed".
if (DoesNonceMatchSourceList(aLoadInfo, mSrcs)) {
CSPUTILSLOG((
" Allowed by matching nonce (script-like)"));
return true;
}
// Step 1.2. Let integrity expressions be the set of source expressions in
// directive’s value that match the hash-source grammar.
nsTArray<nsCSPHashSrc*> integrityExpressions;
bool hasStrictDynamicKeyword =
false;
// Optimization to reduce number of iterations.
for (uint32_t i = 0; i < mSrcs.Length(); i++) {
if (mSrcs[i]->isHash()) {
integrityExpressions.AppendElement(
static_cast<nsCSPHashSrc*>(mSrcs[i]));
}
else if (mSrcs[i]->isKeyword(CSP_STRICT_DYNAMIC)) {
hasStrictDynamicKeyword =
true;
}
}
// Step 1.3. If integrity expressions is not empty:
if (!integrityExpressions.IsEmpty()) {
// Step 1.3.1. Let integrity sources be the result of executing the
// algorithm defined in [SRI 3.3.3 Parse metadata] on request’s
// integrity metadata.
nsAutoString integrityMetadata;
aLoadInfo->GetIntegrityMetadata(integrityMetadata);
nsTArray<SRIMetadata> integritySources =
ParseSRIMetadata(integrityMetadata);
MOZ_ASSERT(
integritySources.IsEmpty() == integrityMetadata.IsEmpty(),
"The integrity metadata should be only be empty, "
"when the parsed string was completely empty, otherwise it should "
"include at least one valid hash");
// Step 1.3.2. If integrity sources is "no metadata" or an empty set,
// skip the remaining substeps.
if (!integritySources.IsEmpty()) {
// Step 1.3.3. Let bypass due to integrity match be true.
bool bypass =
true;
nsAutoCString sourceAlgorithmUTF8;
nsAutoCString sourceHashUTF8;
nsAutoString sourceAlgorithm;
nsAutoString sourceHash;
nsAutoString algorithm;
nsAutoString hash;
// Step 1.3.4. For each source of integrity sources:
for (
const SRIMetadata& source : integritySources) {
source.GetAlgorithm(&sourceAlgorithmUTF8);
sourceAlgorithm = NS_ConvertUTF8toUTF16(sourceAlgorithmUTF8);
source.GetHash(0, &sourceHashUTF8);
sourceHash = NS_ConvertUTF8toUTF16(sourceHashUTF8);
// Step 1.3.4.1 If directive’s value does not contain a source
// expression whose hash-algorithm is an ASCII case-insensitive
// match for source’s hash-algorithm, and whose base64-value is
// identical to source’s base64-value, then set bypass due to
// integrity match to false.
bool found =
false;
for (
const nsCSPHashSrc* hashSrc : integrityExpressions) {
hashSrc->getAlgorithm(algorithm);
hashSrc->getHash(hash);
// The nsCSPHashSrc constructor lowercases algorithm, so this
// is case-insensitive.
if (sourceAlgorithm == algorithm && sourceHash == hash) {
found =
true;
break;
}
}
if (!found) {
bypass =
false;
break;
}
}
// Step 1.3.5. If bypass due to integrity match is true, return
// "Allowed".
if (bypass) {
CSPUTILSLOG(
(
" Allowed by matching integrity metadata (script-like)"));
return true;
}
}
}
// Step 1.4. If directive’s value contains a source expression that is an
// ASCII case-insensitive match for the "'strict-dynamic'" keyword-source:
// XXX I don't think we should apply strict-dynamic to XSLT.
if (hasStrictDynamicKeyword && aLoadInfo->InternalContentPolicyType() !=
nsIContentPolicy::TYPE_XSLT) {
// Step 1.4.1 If the request’s parser metadata is "parser-inserted",
// return "Blocked". Otherwise, return "Allowed".
if (aLoadInfo->GetParserCreatedScript()) {
CSPUTILSLOG(
(
" Blocked by 'strict-dynamic' because parser-inserted"));
return false;
}
CSPUTILSLOG(
(
" Allowed by 'strict-dynamic' because not-parser-inserted"));
return true;
}
}
}
for (uint32_t i = 0; i < mSrcs.Length(); i++) {
if (mSrcs[i]->permits(aUri, aWasRedirected, aReportOnly,
aUpgradeInsecure)) {
return true;
}
}
return false;
}
bool nsCSPDirective::allows(
enum CSPKeyword aKeyword,
const nsAString& aHashOrNonce)
const {
CSPUTILSLOG((
"nsCSPDirective::allows, aKeyWord: %s, aHashOrNonce: %s",
CSP_EnumToUTF8Keyword(aKeyword),
NS_ConvertUTF16toUTF8(aHashOrNonce).get()));
for (uint32_t i = 0; i < mSrcs.Length(); i++) {
if (mSrcs[i]->allows(aKeyword, aHashOrNonce)) {
return true;
}
}
return false;
}
// https://w3c.github.io/webappsec-csp/#allow-all-inline
bool nsCSPDirective::allowsAllInlineBehavior(CSPDirective aDir)
const {
// Step 1. Let allow all inline be false.
bool allowAll =
false;
// Step 2. For each expression of list:
for (nsCSPBaseSrc* src : mSrcs) {
// Step 2.1. If expression matches the nonce-source or hash-source grammar,
// return "Does Not Allow".
if (src->isNonce() || src->isHash()) {
return false;
}
// Step 2.2. If type is "script", "script attribute" or "navigation" and
// expression matches the keyword-source "'strict-dynamic'", return "Does
// Not Allow".
if ((aDir == nsIContentSecurityPolicy::SCRIPT_SRC_ELEM_DIRECTIVE ||
aDir == nsIContentSecurityPolicy::SCRIPT_SRC_ATTR_DIRECTIVE) &&
src->isKeyword(CSP_STRICT_DYNAMIC)) {
return false;
}
// Step 2.3. If expression is an ASCII case-insensitive match for the
// keyword-source "'unsafe-inline'", set allow all inline to true.
if (src->isKeyword(CSP_UNSAFE_INLINE)) {
allowAll =
true;
}
}
// Step 3. If allow all inline is true, return "Allows". Otherwise, return
// "Does Not Allow".
return allowAll;
}
static constexpr
auto kWildcard = u
"*"_ns;
bool nsCSPDirective::ShouldCreateViolationForNewTrustedTypesPolicy(
const nsAString& aPolicyName,
const nsTArray<nsString>& aCreatedPolicyNames)
const {
MOZ_ASSERT(mDirective == nsIContentSecurityPolicy::TRUSTED_TYPES_DIRECTIVE);
if (mDirective == nsIContentSecurityPolicy::TRUSTED_TYPES_DIRECTIVE) {
if (allows(CSP_NONE, EmptyString())) {
// Step 2.4: if directive’s value only contains a tt-keyword which is a
// match for a value 'none', set createViolation to true.
// `nsCSPParser` ignores the 'none' keyword if other keywords or policy
// names are present. Hence no additional checks required here.
return true;
}
if (aCreatedPolicyNames.Contains(aPolicyName) &&
!allows(CSP_ALLOW_DUPLICATES, EmptyString())) {
// Step 2.5: if createdPolicyNames contains policyName and directive’s
// value does not contain a tt-keyword which is a match for a value
// 'allow-duplicates', set createViolation to true.
return true;
}
if (!ContainsTrustedTypesDirectivePolicyName(aPolicyName) &&
!ContainsTrustedTypesDirectivePolicyName(kWildcard)) {
// Step 2.6: if directive’s value does not contain a tt-policy-name, which
// value is policyName, and directive’s value does not contain a
// tt-wildcard, set createViolation to true.
return true;
}
}
return false;
}
void nsCSPDirective::toString(nsAString& outStr)
const {
// Append directive name
outStr.AppendASCII(CSP_CSPDirectiveToString(mDirective));
MOZ_ASSERT(!mSrcs.IsEmpty());
outStr.AppendLiteral(
" ");
// Append srcs
StringJoinAppend(outStr, u
" "_ns, mSrcs,
[](nsAString& dest, nsCSPBaseSrc* cspBaseSrc) {
cspBaseSrc->toString(dest);
});
}
void nsCSPDirective::toDomCSPStruct(mozilla::dom::CSP& outCSP)
const {
mozilla::dom::Sequence<nsString> srcs;
nsString src;
if (NS_WARN_IF(!srcs.SetCapacity(mSrcs.Length(), mozilla::fallible))) {
MOZ_ASSERT(
false,
"Not enough memory for 'sources' sequence in "
"nsCSPDirective::toDomCSPStruct().");
return;
}
for (uint32_t i = 0; i < mSrcs.Length(); i++) {
src.Truncate();
mSrcs[i]->toString(src);
if (!srcs.AppendElement(src, mozilla::fallible)) {
MOZ_ASSERT(
false,
"Failed to append to 'sources' sequence in "
"nsCSPDirective::toDomCSPStruct().");
}
}
switch (mDirective) {
case nsIContentSecurityPolicy::DEFAULT_SRC_DIRECTIVE:
outCSP.mDefault_src.Construct();
outCSP.mDefault_src.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::SCRIPT_SRC_DIRECTIVE:
outCSP.mScript_src.Construct();
outCSP.mScript_src.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::OBJECT_SRC_DIRECTIVE:
outCSP.mObject_src.Construct();
outCSP.mObject_src.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::STYLE_SRC_DIRECTIVE:
outCSP.mStyle_src.Construct();
outCSP.mStyle_src.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::IMG_SRC_DIRECTIVE:
outCSP.mImg_src.Construct();
outCSP.mImg_src.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::MEDIA_SRC_DIRECTIVE:
outCSP.mMedia_src.Construct();
outCSP.mMedia_src.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::FRAME_SRC_DIRECTIVE:
outCSP.mFrame_src.Construct();
outCSP.mFrame_src.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::FONT_SRC_DIRECTIVE:
outCSP.mFont_src.Construct();
outCSP.mFont_src.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::CONNECT_SRC_DIRECTIVE:
outCSP.mConnect_src.Construct();
outCSP.mConnect_src.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::REPORT_URI_DIRECTIVE:
outCSP.mReport_uri.Construct();
outCSP.mReport_uri.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::FRAME_ANCESTORS_DIRECTIVE:
outCSP.mFrame_ancestors.Construct();
outCSP.mFrame_ancestors.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::WEB_MANIFEST_SRC_DIRECTIVE:
outCSP.mManifest_src.Construct();
outCSP.mManifest_src.Value() = std::move(srcs);
return;
// not supporting REFLECTED_XSS_DIRECTIVE
case nsIContentSecurityPolicy::BASE_URI_DIRECTIVE:
outCSP.mBase_uri.Construct();
outCSP.mBase_uri.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::FORM_ACTION_DIRECTIVE:
outCSP.mForm_action.Construct();
outCSP.mForm_action.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::BLOCK_ALL_MIXED_CONTENT:
outCSP.mBlock_all_mixed_content.Construct();
// does not have any srcs
return;
case nsIContentSecurityPolicy::UPGRADE_IF_INSECURE_DIRECTIVE:
outCSP.mUpgrade_insecure_requests.Construct();
// does not have any srcs
return;
case nsIContentSecurityPolicy::CHILD_SRC_DIRECTIVE:
outCSP.mChild_src.Construct();
outCSP.mChild_src.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::SANDBOX_DIRECTIVE:
outCSP.mSandbox.Construct();
outCSP.mSandbox.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::WORKER_SRC_DIRECTIVE:
outCSP.mWorker_src.Construct();
outCSP.mWorker_src.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::SCRIPT_SRC_ELEM_DIRECTIVE:
outCSP.mScript_src_elem.Construct();
outCSP.mScript_src_elem.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::SCRIPT_SRC_ATTR_DIRECTIVE:
outCSP.mScript_src_attr.Construct();
outCSP.mScript_src_attr.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::REQUIRE_TRUSTED_TYPES_FOR_DIRECTIVE:
outCSP.mRequire_trusted_types_for.Construct();
// Here, the srcs represent the sink group
// (https://w3c.github.io/trusted-types/dist/spec/#integration-with-content-security-policy).
outCSP.mRequire_trusted_types_for.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::TRUSTED_TYPES_DIRECTIVE:
outCSP.mTrusted_types.Construct();
// Here, "srcs" represents tt-expressions
// (https://w3c.github.io/trusted-types/dist/spec/#trusted-types-csp-directive).
outCSP.mTrusted_types.Value() = std::move(srcs);
return;
case nsIContentSecurityPolicy::REPORT_TO_DIRECTIVE:
outCSP.mReport_to.Construct();
outCSP.mReport_to.Value() = std::move(srcs);
return;
default:
NS_ASSERTION(
false,
"cannot find directive to convert CSP to JSON");
}
}
bool nsCSPDirective::isDefaultDirective()
const {
return mDirective == nsIContentSecurityPolicy::DEFAULT_SRC_DIRECTIVE;
}
void nsCSPDirective::getReportURIs(nsTArray<nsString>& outReportURIs)
const {
NS_ASSERTION((mDirective == nsIContentSecurityPolicy::REPORT_URI_DIRECTIVE),
"not a report-uri directive");
// append uris
nsString tmpReportURI;
for (uint32_t i = 0; i < mSrcs.Length(); i++) {
tmpReportURI.Truncate();
mSrcs[i]->toString(tmpReportURI);
outReportURIs.AppendElement(tmpReportURI);
}
}
void nsCSPDirective::getReportGroup(nsAString& outReportGroup)
const {
NS_ASSERTION((mDirective == nsIContentSecurityPolicy::REPORT_TO_DIRECTIVE),
"not a report-to directive");
MOZ_ASSERT(mSrcs.Length() <= 1);
mSrcs[0]->toString(outReportGroup);
}
bool nsCSPDirective::visitSrcs(nsCSPSrcVisitor* aVisitor)
const {
for (uint32_t i = 0; i < mSrcs.Length(); i++) {
if (!mSrcs[i]->visit(aVisitor)) {
return false;
}
}
return true;
}
bool nsCSPDirective::equals(CSPDirective aDirective)
const {
return (mDirective == aDirective);
}
void nsCSPDirective::getDirName(nsAString& outStr)
const {
outStr.AppendASCII(CSP_CSPDirectiveToString(mDirective));
}
bool nsCSPDirective::hasReportSampleKeyword()
const {
for (nsCSPBaseSrc* src : mSrcs) {
if (src->isReportSample()) {
return true;
}
}
return false;
}
bool nsCSPDirective::ContainsTrustedTypesDirectivePolicyName(
const nsAString& aPolicyName)
const {
MOZ_ASSERT(mDirective == nsIContentSecurityPolicy::TRUSTED_TYPES_DIRECTIVE);
if (mDirective == nsIContentSecurityPolicy::TRUSTED_TYPES_DIRECTIVE) {
for (
const auto* src : mSrcs) {
if (src->isTrustedTypesDirectivePolicyName()) {
const auto& name =
static_cast<
const nsCSPTrustedTypesDirectivePolicyName*>(src)
->GetName();
if (name.Equals(aPolicyName)) {
return true;
}
}
}
}
return false;
}
/* =============== nsCSPChildSrcDirective ============= */
nsCSPChildSrcDirective::nsCSPChildSrcDirective(CSPDirective aDirective)
: nsCSPDirective(aDirective),
mRestrictFrames(
false),
mRestrictWorkers(
false) {}
nsCSPChildSrcDirective::~nsCSPChildSrcDirective() =
default;
bool nsCSPChildSrcDirective::equals(CSPDirective aDirective)
const {
if (aDirective == nsIContentSecurityPolicy::FRAME_SRC_DIRECTIVE) {
return mRestrictFrames;
}
if (aDirective == nsIContentSecurityPolicy::WORKER_SRC_DIRECTIVE) {
return mRestrictWorkers;
}
return (mDirective == aDirective);
}
/* =============== nsCSPScriptSrcDirective ============= */
nsCSPScriptSrcDirective::nsCSPScriptSrcDirective(CSPDirective aDirective)
: nsCSPDirective(aDirective) {}
nsCSPScriptSrcDirective::~nsCSPScriptSrcDirective() =
default;
bool nsCSPScriptSrcDirective::equals(CSPDirective aDirective)
const {
if (aDirective == nsIContentSecurityPolicy::WORKER_SRC_DIRECTIVE) {
return mRestrictWorkers;
}
if (aDirective == nsIContentSecurityPolicy::SCRIPT_SRC_ELEM_DIRECTIVE) {
return mRestrictScriptElem;
}
if (aDirective == nsIContentSecurityPolicy::SCRIPT_SRC_ATTR_DIRECTIVE) {
return mRestrictScriptAttr;
}
return mDirective == aDirective;
}
/* =============== nsCSPStyleSrcDirective ============= */
nsCSPStyleSrcDirective::nsCSPStyleSrcDirective(CSPDirective aDirective)
: nsCSPDirective(aDirective) {}
nsCSPStyleSrcDirective::~nsCSPStyleSrcDirective() =
default;
bool nsCSPStyleSrcDirective::equals(CSPDirective aDirective)
const {
if (aDirective == nsIContentSecurityPolicy::STYLE_SRC_ELEM_DIRECTIVE) {
return mRestrictStyleElem;
}
if (aDirective == nsIContentSecurityPolicy::STYLE_SRC_ATTR_DIRECTIVE) {
return mRestrictStyleAttr;
}
return mDirective == aDirective;
}
/* =============== nsBlockAllMixedContentDirective ============= */
nsBlockAllMixedContentDirective::nsBlockAllMixedContentDirective(
CSPDirective aDirective)
: nsCSPDirective(aDirective) {}
nsBlockAllMixedContentDirective::~nsBlockAllMixedContentDirective() =
default;
void nsBlockAllMixedContentDirective::toString(nsAString& outStr)
const {
outStr.AppendASCII(CSP_CSPDirectiveToString(
nsIContentSecurityPolicy::BLOCK_ALL_MIXED_CONTENT));
}
void nsBlockAllMixedContentDirective::getDirName(nsAString& outStr)
const {
outStr.AppendASCII(CSP_CSPDirectiveToString(
nsIContentSecurityPolicy::BLOCK_ALL_MIXED_CONTENT));
}
/* =============== nsUpgradeInsecureDirective ============= */
nsUpgradeInsecureDirective::nsUpgradeInsecureDirective(CSPDirective aDirective)
: nsCSPDirective(aDirective) {}
nsUpgradeInsecureDirective::~nsUpgradeInsecureDirective() =
default;
void nsUpgradeInsecureDirective::toString(nsAString& outStr)
const {
outStr.AppendASCII(CSP_CSPDirectiveToString(
nsIContentSecurityPolicy::UPGRADE_IF_INSECURE_DIRECTIVE));
}
void nsUpgradeInsecureDirective::getDirName(nsAString& outStr)
const {
outStr.AppendASCII(CSP_CSPDirectiveToString(
nsIContentSecurityPolicy::UPGRADE_IF_INSECURE_DIRECTIVE));
}
/* ===== nsCSPPolicy ========================= */
nsCSPPolicy::nsCSPPolicy()
: mUpgradeInsecDir(nullptr),
mReportOnly(
false),
mDeliveredViaMetaTag(
false) {
CSPUTILSLOG((
"nsCSPPolicy::nsCSPPolicy"));
}
nsCSPPolicy::~nsCSPPolicy() {
CSPUTILSLOG((
"nsCSPPolicy::~nsCSPPolicy"));
for (uint32_t i = 0; i < mDirectives.Length(); i++) {
delete mDirectives[i];
}
}
bool nsCSPPolicy::permits(CSPDirective aDir, nsILoadInfo* aLoadInfo,
nsIURI* aUri,
bool aWasRedirected,
bool aSpecific,
nsAString& outViolatedDirective,
nsAString& outViolatedDirectiveString)
const {
if (CSPUTILSLOGENABLED()) {
CSPUTILSLOG((
"nsCSPPolicy::permits, aUri: %s, aDir: %s, aSpecific: %s",
aUri->GetSpecOrDefault().get(), CSP_CSPDirectiveToString(aDir),
aSpecific ?
"true" :
"false"));
}
NS_ASSERTION(aUri,
"permits needs an uri to perform the check!");
outViolatedDirective.Truncate();
outViolatedDirectiveString.Truncate();
nsCSPDirective* defaultDir = nullptr;
// Try to find a relevant directive
// These directive arrays are short (1-5 elements), not worth using a
// hashtable.
for (uint32_t i = 0; i < mDirectives.Length(); i++) {
if (mDirectives[i]->equals(aDir)) {
if (!mDirectives[i]->permits(aDir, aLoadInfo, aUri, aWasRedirected,
mReportOnly, mUpgradeInsecDir)) {
mDirectives[i]->getDirName(outViolatedDirective);
mDirectives[i]->toString(outViolatedDirectiveString);
return false;
}
return true;
}
if (mDirectives[i]->isDefaultDirective()) {
defaultDir = mDirectives[i];
}
}
// If the above loop runs through, we haven't found a matching directive.
// Avoid relooping, just store the result of default-src while looping.
if (!aSpecific && defaultDir) {
if (!defaultDir->permits(aDir, aLoadInfo, aUri, aWasRedirected, mReportOnly,
mUpgradeInsecDir)) {
defaultDir->getDirName(outViolatedDirective);
defaultDir->toString(outViolatedDirectiveString);
return false;
}
return true;
}
// Nothing restricts this, so we're allowing the load
// See bug 764937
return true;
}
bool nsCSPPolicy::allows(CSPDirective aDirective,
enum CSPKeyword aKeyword,
const nsAString& aHashOrNonce)
const {
CSPUTILSLOG((
"nsCSPPolicy::allows, aKeyWord: %s, a HashOrNonce: %s",
CSP_EnumToUTF8Keyword(aKeyword),
NS_ConvertUTF16toUTF8(aHashOrNonce).get()));
if (nsCSPDirective* directive = matchingOrDefaultDirective(aDirective)) {
return directive->allows(aKeyword, aHashOrNonce);
}
// No matching directive or default directive as fallback found, thus
// allowing the load; see Bug 885433
// a) inline scripts (also unsafe eval) should only be blocked
// if there is a [script-src] or [default-src]
// b) inline styles should only be blocked
// if there is a [style-src] or [default-src]
return true;
}
nsCSPDirective* nsCSPPolicy::matchingOrDefaultDirective(
CSPDirective aDirective)
const {
nsCSPDirective* defaultDir = nullptr;
// Try to find a matching directive
for (uint32_t i = 0; i < mDirectives.Length(); i++) {
if (mDirectives[i]->isDefaultDirective()) {
defaultDir = mDirectives[i];
continue;
}
if (mDirectives[i]->equals(aDirective)) {
return mDirectives[i];
}
}
return defaultDir;
}
void nsCSPPolicy::toString(nsAString& outStr)
const {
StringJoinAppend(outStr, u
"; "_ns, mDirectives,
[](nsAString& dest, nsCSPDirective* cspDirective) {
cspDirective->toString(dest);
});
}
void nsCSPPolicy::toDomCSPStruct(mozilla::dom::CSP& outCSP)
const {
outCSP.mReport_only = mReportOnly;
for (uint32_t i = 0; i < mDirectives.Length(); ++i) {
mDirectives[i]->toDomCSPStruct(outCSP);
}
}
bool nsCSPPolicy::hasDirective(CSPDirective aDir)
const {
for (uint32_t i = 0; i < mDirectives.Length(); i++) {
if (mDirectives[i]->equals(aDir)) {
return true;
}
}
return false;
}
bool nsCSPPolicy::allowsAllInlineBehavior(CSPDirective aDir)
const {
nsCSPDirective* directive = matchingOrDefaultDirective(aDir);
if (!directive) {
// No matching or default directive found thus allow the all inline
// scripts or styles. (See nsCSPPolicy::allows)
return true;
}
return directive->allowsAllInlineBehavior(aDir);
}
bool nsCSPPolicy::ShouldCreateViolationForNewTrustedTypesPolicy(
const nsAString& aPolicyName,
const nsTArray<nsString>& aCreatedPolicyNames)
const {
for (
const auto* directive : mDirectives) {
if (directive->equals(nsIContentSecurityPolicy::TRUSTED_TYPES_DIRECTIVE)) {
return directive->ShouldCreateViolationForNewTrustedTypesPolicy(
aPolicyName, aCreatedPolicyNames);
}
}
return false;
}
bool nsCSPPolicy::AreTrustedTypesForSinkGroupRequired(
const nsAString& aSinkGroup)
const {
MOZ_ASSERT(aSinkGroup == dom::kTrustedTypesOnlySinkGroup);
return mHasRequireTrustedTypesForDirective;
}
/*
* Use this function only after ::allows() returned 'false' or if ensured by
* other means that the directive is violated. First and foremost it's used to
* get the violated directive before sending reports. The parameter
* aDirectiveName is the equivalent of 'outViolatedDirective' for the
* ::permits() function family.
*/
void nsCSPPolicy::getViolatedDirectiveInformation(
CSPDirective aDirective, nsAString& aDirectiveName,
nsAString& aDirectiveNameAndValue,
bool* aReportSample)
const {
*aReportSample =
false;
nsCSPDirective* directive = matchingOrDefaultDirective(aDirective);
if (!directive) {
MOZ_ASSERT_UNREACHABLE(
"Can not query violated directive");
aDirectiveName.Truncate();
aDirectiveNameAndValue.Truncate();
return;
}
directive->getDirName(aDirectiveName);
directive->toString(aDirectiveNameAndValue);
*aReportSample = directive->hasReportSampleKeyword();
}
/*
* Helper function that returns the underlying bit representation of sandbox
* flags. The function returns SANDBOXED_NONE if there are no sandbox
* directives.
*/
uint32_t nsCSPPolicy::getSandboxFlags()
const {
for (uint32_t i = 0; i < mDirectives.Length(); i++) {
if (mDirectives[i]->equals(nsIContentSecurityPolicy::SANDBOX_DIRECTIVE)) {
nsAutoString flags;
mDirectives[i]->toString(flags);
if (flags.IsEmpty()) {
return SANDBOX_ALL_FLAGS;
}
nsAttrValue attr;
attr.ParseAtomArray(flags);
return nsContentUtils::ParseSandboxAttributeToFlags(&attr);
}
}
return SANDBOXED_NONE;
}
--> --------------------
--> maximum size reached
--> --------------------