Implementation of W3C compliant CSP script-src nonce.

Source/core/page/ContentSecurityPolicy.cpp

Index: Source/core/page/ContentSecurityPolicy.cpp
diff --git a/Source/core/page/ContentSecurityPolicy.cpp b/Source/core/page/ContentSecurityPolicy.cpp
index 650b43bf8e2cb3e6a41b9164f1bfe58838baf167..6d4479d5a02775f37fbc47edde0ad5ba36d47ef6 100644
--- a/Source/core/page/ContentSecurityPolicy.cpp
+++ b/Source/core/page/ContentSecurityPolicy.cpp
@@ -71,7 +71,7 @@ bool isDirectiveValueCharacter(UChar c)
 
 bool isNonceCharacter(UChar c)
 {
-    return (c >= 0x21 && c <= 0x7e) && c != ',' && c != ';'; // VCHAR - ',' - ';'
+    return isASCIIAlphanumeric(c);
 }
 
 bool isSourceCharacter(UChar c)
@@ -126,7 +126,6 @@ static const char styleSrc[] = "style-src";
 static const char baseURI[] = "base-uri";
 static const char formAction[] = "form-action";
 static const char pluginTypes[] = "plugin-types";
-static const char scriptNonce[] = "script-nonce";
 static const char reflectedXSS[] = "reflected-xss";
 
 bool isDirectiveName(const String& name)
@@ -145,7 +144,6 @@ bool isDirectiveName(const String& name)
         || equalIgnoringCase(name, baseURI)
         || equalIgnoringCase(name, formAction)
         || equalIgnoringCase(name, pluginTypes)
-        || equalIgnoringCase(name, scriptNonce)
         || equalIgnoringCase(name, reflectedXSS)
     );
 }
@@ -313,6 +311,7 @@ public:
     bool matches(const KURL&);
     bool allowInline() const { return m_allowInline; }
     bool allowEval() const { return m_allowEval; }
+    bool allowNonce(const String& nonce) const { return !nonce.isNull() && m_nonces.contains(nonce); }
 
 private:
     void parse(const UChar* begin, const UChar* end);
@@ -322,11 +321,13 @@ private:
     bool parseHost(const UChar* begin, const UChar* end, String& host, bool& hostHasWildcard);
     bool parsePort(const UChar* begin, const UChar* end, int& port, bool& portHasWildcard);
     bool parsePath(const UChar* begin, const UChar* end, String& path);
+    bool parseNonce(const UChar* begin, const UChar* end, String& nonce);
 
     void addSourceSelf();
     void addSourceStar();
     void addSourceUnsafeInline();
     void addSourceUnsafeEval();
+    void addSourceNonce(const String& nonce);
 
     ContentSecurityPolicy* m_policy;
     Vector<CSPSource> m_list;
@@ -334,6 +335,7 @@ private:
     bool m_allowStar;
     bool m_allowInline;
     bool m_allowEval;
+    HashSet<String> m_nonces;
 };
 
 CSPSourceList::CSPSourceList(ContentSecurityPolicy* policy, const String& directiveName)
@@ -438,6 +440,15 @@ bool CSPSourceList::parseSource(const UChar* begin, const UChar* end,
         return true;
     }
 
+    String nonce;
+    if (!parseNonce(begin, end, nonce))
+        return false;
+
+    if (!nonce.isNull()) {
+        addSourceNonce(nonce);
+        return true;
+    }
+
     const UChar* position = begin;
     const UChar* beginHost = begin;
     const UChar* beginPath = end;
@@ -517,6 +528,29 @@ bool CSPSourceList::parseSource(const UChar* begin, const UChar* end,
     return true;
 }
 
+// nonce-source      = "'nonce-" nonce-value "'"
+// nonce-value       = *( ALPHA / DIGIT )
+//
+bool CSPSourceList::parseNonce(const UChar* begin, const UChar* end, String& nonce)
+{
+    DEFINE_STATIC_LOCAL(const String, noncePrefix, (ASCIILiteral("'nonce-")));
+
+    if (!equalIgnoringCase(noncePrefix.characters(), begin, noncePrefix.length()))
+        return true;
+
+    const UChar* position = begin + noncePrefix.length();
+    const UChar* nonceBegin = position;
+
+    skipWhile<isNonceCharacter>(position, end);
+    ASSERT(nonceBegin <= position);
+    nonce = String(nonceBegin, position - nonceBegin);
+
+    if ((position + 1) != end  && *position != '\'')
+        return false;
+
+    return true;
+}
+
 //                     ; <scheme> production from RFC 3986
 // scheme      = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )
 //
@@ -654,6 +688,11 @@ void CSPSourceList::addSourceUnsafeEval()
     m_allowEval = true;
 }
 
+void CSPSourceList::addSourceNonce(const String& nonce)
+{
+    m_nonces.add(nonce);
+}
+
 class CSPDirective {
 public:
     CSPDirective(const String& name, const String& value, ContentSecurityPolicy* policy)
@@ -674,50 +713,6 @@ private:
     ContentSecurityPolicy* m_policy;
 };
 
-class NonceDirective : public CSPDirective {
-public:
-    NonceDirective(const String& name, const String& value, ContentSecurityPolicy* policy)
-        : CSPDirective(name, value, policy)
-    {
-        parse(value);
-    }
-
-    bool allows(const String& nonce) const
-    {
-        return (!m_scriptNonce.isEmpty() && nonce.stripWhiteSpace() == m_scriptNonce);
-    }
-
-private:
-    void parse(const String& value)
-    {
-        String nonce;
-        const UChar* position = value.characters();
-        const UChar* end = position + value.length();
-
-        skipWhile<isASCIISpace>(position, end);
-        const UChar* nonceBegin = position;
-        if (position == end) {
-            policy()->reportInvalidNonce(String());
-            m_scriptNonce = "";
-            return;
-        }
-        skipWhile<isNonceCharacter>(position, end);
-        if (nonceBegin < position)
-            nonce = String(nonceBegin, position - nonceBegin);
-
-        // Trim off trailing whitespace: If we're not at the end of the string, log
-        // an error.
-        skipWhile<isASCIISpace>(position, end);
-        if (position < end) {
-            policy()->reportInvalidNonce(value);
-            m_scriptNonce = "";
-        } else
-            m_scriptNonce = nonce;
-    }
-
-    String m_scriptNonce;
-};
-
 class MediaListDirective : public CSPDirective {
 public:
     MediaListDirective(const String& name, const String& value, ContentSecurityPolicy* policy)
@@ -810,6 +805,7 @@ public:
 
     bool allowInline() const { return m_sourceList.allowInline(); }
     bool allowEval() const { return m_sourceList.allowEval(); }
+    bool allowNonce(const String& nonce) const { return m_sourceList.allowNonce(nonce.stripWhiteSpace()); }
 
 private:
     CSPSourceList m_sourceList;
@@ -828,7 +824,6 @@ public:
     bool allowInlineScript(const String& contextURL, const WTF::OrdinalNumber& contextLine, ContentSecurityPolicy::ReportingStatus) const;
     bool allowInlineStyle(const String& contextURL, const WTF::OrdinalNumber& contextLine, ContentSecurityPolicy::ReportingStatus) const;
     bool allowEval(ScriptState*, ContentSecurityPolicy::ReportingStatus) const;
-    bool allowScriptNonce(const String& nonce, const String& contextURL, const WTF::OrdinalNumber& contextLine, const KURL&) const;
     bool allowPluginType(const String& type, const String& typeAttribute, const KURL&, ContentSecurityPolicy::ReportingStatus) const;
 
     bool allowScriptFromSource(const KURL&, ContentSecurityPolicy::ReportingStatus) const;
@@ -841,6 +836,7 @@ public:
     bool allowConnectToSource(const KURL&, ContentSecurityPolicy::ReportingStatus) const;
     bool allowFormAction(const KURL&, ContentSecurityPolicy::ReportingStatus) const;
     bool allowBaseURI(const KURL&, ContentSecurityPolicy::ReportingStatus) const;
+    bool allowScriptNonce(const String&) const;
 
     void gatherReportURIs(DOMStringList&) const;
     const String& evalDisabledErrorMessage() { return m_evalDisabledErrorMessage; }
@@ -855,7 +851,6 @@ private:
 
     bool parseDirective(const UChar* begin, const UChar* end, String& name, String& value);
     void parseReportURI(const String& name, const String& value);
-    void parseScriptNonce(const String& name, const String& value);
     void parsePluginTypes(const String& name, const String& value);
     void parseReflectedXSS(const String& name, const String& value);
     void addDirective(const String& name, const String& value);
@@ -869,7 +864,7 @@ private:
 
     bool checkEval(SourceListDirective*) const;
     bool checkInline(SourceListDirective*) const;
-    bool checkNonce(NonceDirective*, const String&) const;
+    bool checkNonce(SourceListDirective*, const String&) const;
     bool checkSource(SourceListDirective*, const KURL&) const;
     bool checkMediaType(MediaListDirective*, const String& type, const String& typeAttribute) const;
 
@@ -877,7 +872,6 @@ private:
 
     bool checkEvalAndReportViolation(SourceListDirective*, const String& consoleMessage, const String& contextURL = String(), const WTF::OrdinalNumber& contextLine = WTF::OrdinalNumber::beforeFirst(), ScriptState* = 0) const;
     bool checkInlineAndReportViolation(SourceListDirective*, const String& consoleMessage, const String& contextURL, const WTF::OrdinalNumber& contextLine, bool isScript) const;
-    bool checkNonceAndReportViolation(NonceDirective*, const String& nonce, const String& consoleMessage, const String& contextURL, const WTF::OrdinalNumber& contextLine) const;
 
     bool checkSourceAndReportViolation(SourceListDirective*, const KURL&, const String& effectiveDirective) const;
     bool checkMediaTypeAndReportViolation(MediaListDirective*, const String& type, const String& typeAttribute, const String& consoleMessage) const;
@@ -894,7 +888,6 @@ private:
     ContentSecurityPolicy::ReflectedXSSDisposition m_reflectedXSSDisposition;
 
     OwnPtr<MediaListDirective> m_pluginTypes;
-    OwnPtr<NonceDirective> m_scriptNonce;
     OwnPtr<SourceListDirective> m_baseURI;
     OwnPtr<SourceListDirective> m_connectSrc;
     OwnPtr<SourceListDirective> m_defaultSrc;
@@ -954,9 +947,9 @@ bool CSPDirectiveList::checkInline(SourceListDirective* directive) const
     return !directive || directive->allowInline();
 }
 
-bool CSPDirectiveList::checkNonce(NonceDirective* directive, const String& nonce) const
+bool CSPDirectiveList::checkNonce(SourceListDirective* directive, const String& nonce) const
 {
-    return !directive || directive->allows(nonce);
+    return !directive || directive->allowNonce(nonce);
 }
 
 bool CSPDirectiveList::checkSource(SourceListDirective* directive, const KURL& url) const
@@ -995,14 +988,6 @@ bool CSPDirectiveList::checkEvalAndReportViolation(SourceListDirective* directiv
     return true;
 }
 
-bool CSPDirectiveList::checkNonceAndReportViolation(NonceDirective* directive, const String& nonce, const String& consoleMessage, const String& contextURL, const WTF::OrdinalNumber& contextLine) const
-{
-    if (checkNonce(directive, nonce))
-        return true;
-    reportViolation(directive->text(), scriptNonce, consoleMessage + "\"" + directive->text() + "\".\n", KURL(), contextURL, contextLine);
-    return denyIfEnforcingPolicy();
-}
-
 bool CSPDirectiveList::checkMediaTypeAndReportViolation(MediaListDirective* directive, const String& type, const String& typeAttribute, const String& consoleMessage) const
 {
     if (checkMediaType(directive, type, typeAttribute))
@@ -1074,11 +1059,9 @@ bool CSPDirectiveList::allowJavaScriptURLs(const String& contextURL, const WTF::
 {
     DEFINE_STATIC_LOCAL(String, consoleMessage, (ASCIILiteral("Refused to execute JavaScript URL because it violates the following Content Security Policy directive: ")));
     if (reportingStatus == ContentSecurityPolicy::SendReport) {
-        return (checkInlineAndReportViolation(operativeDirective(m_scriptSrc.get()), consoleMessage, contextURL, contextLine, true)
-                && checkNonceAndReportViolation(m_scriptNonce.get(), String(), consoleMessage, contextURL, contextLine));
+        return checkInlineAndReportViolation(operativeDirective(m_scriptSrc.get()), consoleMessage, contextURL, contextLine, true);
     } else {
-        return (checkInline(operativeDirective(m_scriptSrc.get()))
-                && checkNonce(m_scriptNonce.get(), String()));
+        return checkInline(operativeDirective(m_scriptSrc.get()));
     }
 }
 
@@ -1086,11 +1069,9 @@ bool CSPDirectiveList::allowInlineEventHandlers(const String& contextURL, const
 {
     DEFINE_STATIC_LOCAL(String, consoleMessage, (ASCIILiteral("Refused to execute inline event handler because it violates the following Content Security Policy directive: ")));
     if (reportingStatus == ContentSecurityPolicy::SendReport) {
-        return (checkInlineAndReportViolation(operativeDirective(m_scriptSrc.get()), consoleMessage, contextURL, contextLine, true)
-                && checkNonceAndReportViolation(m_scriptNonce.get(), String(), consoleMessage, contextURL, contextLine));
+        return checkInlineAndReportViolation(operativeDirective(m_scriptSrc.get()), consoleMessage, contextURL, contextLine, true);
     } else {
-        return (checkInline(operativeDirective(m_scriptSrc.get()))
-                && checkNonce(m_scriptNonce.get(), String()));
+        return checkInline(operativeDirective(m_scriptSrc.get()));
     }
 }
 
@@ -1118,14 +1099,6 @@ bool CSPDirectiveList::allowEval(ScriptState* state, ContentSecurityPolicy::Repo
         checkEval(operativeDirective(m_scriptSrc.get()));
 }
 
-bool CSPDirectiveList::allowScriptNonce(const String& nonce, const String& contextURL, const WTF::OrdinalNumber& contextLine, const KURL& url) const
-{
-    DEFINE_STATIC_LOCAL(String, consoleMessage, (ASCIILiteral("Refused to execute script because it violates the following Content Security Policy directive: ")));
-    if (url.isEmpty())
-        return checkNonceAndReportViolation(m_scriptNonce.get(), nonce, consoleMessage, contextURL, contextLine);
-    return checkNonceAndReportViolation(m_scriptNonce.get(), nonce, "Refused to load '" + url.elidedString() + "' because it violates the following Content Security Policy directive: ", contextURL, contextLine);
-}
-
 bool CSPDirectiveList::allowPluginType(const String& type, const String& typeAttribute, const KURL& url, ContentSecurityPolicy::ReportingStatus reportingStatus) const
 {
     return reportingStatus == ContentSecurityPolicy::SendReport ?
@@ -1213,6 +1186,11 @@ bool CSPDirectiveList::allowBaseURI(const KURL& url, ContentSecurityPolicy::Repo
         checkSource(m_baseURI.get(), url);
 }
 
+bool CSPDirectiveList::allowScriptNonce(const String& nonce) const
+{
+    return checkNonce(operativeDirective(m_scriptSrc.get()), nonce);
+}
+
 // policy            = directive-list
 // directive-list    = [ directive *( ";" [ directive ] ) ]
 //
@@ -1419,8 +1397,6 @@ void CSPDirectiveList::addDirective(const String& name, const String& value)
             setCSPDirective<SourceListDirective>(name, value, m_formAction);
         else if (equalIgnoringCase(name, pluginTypes))
             setCSPDirective<MediaListDirective>(name, value, m_pluginTypes);
-        else if (equalIgnoringCase(name, scriptNonce))
-            setCSPDirective<NonceDirective>(name, value, m_scriptNonce);
         else if (equalIgnoringCase(name, reflectedXSS))
             parseReflectedXSS(name, value);
         else
@@ -1526,16 +1502,15 @@ bool isAllowedByAllWithContext(const CSPDirectiveListVector& policies, const Str
     return true;
 }
 
-template<bool (CSPDirectiveList::*allowed)(const String&, const String&, const WTF::OrdinalNumber&, const KURL&) const>
-bool isAllowedByAllWithNonce(const CSPDirectiveListVector& policies, const String& nonce, const String& contextURL, const WTF::OrdinalNumber& contextLine, const KURL& url)
+template<bool (CSPDirectiveList::*allowed)(const String&) const>
+bool isAllowedByAllWithNonce(const CSPDirectiveListVector& policies, const String& nonce)
 {
     for (size_t i = 0; i < policies.size(); ++i) {
-        if (!(policies[i].get()->*allowed)(nonce, contextURL, contextLine, url))
+        if (!(policies[i].get()->*allowed)(nonce))
             return false;
     }
     return true;
 }
-
 template<bool (CSPDirectiveList::*allowFromURL)(const KURL&, ContentSecurityPolicy::ReportingStatus) const>
 bool isAllowedByAllWithURL(const CSPDirectiveListVector& policies, const KURL& url, ContentSecurityPolicy::ReportingStatus reportingStatus)
 {
@@ -1585,11 +1560,6 @@ String ContentSecurityPolicy::evalDisabledErrorMessage() const
     return String();
 }
 
-bool ContentSecurityPolicy::allowScriptNonce(const String& nonce, const String& contextURL, const WTF::OrdinalNumber& contextLine, const KURL& url) const
-{
-    return isAllowedByAllWithNonce<&CSPDirectiveList::allowScriptNonce>(m_policies, nonce, contextURL, contextLine, url);
-}
-
 bool ContentSecurityPolicy::allowPluginType(const String& type, const String& typeAttribute, const KURL& url, ContentSecurityPolicy::ReportingStatus reportingStatus) const
 {
     for (size_t i = 0; i < m_policies.size(); ++i) {
@@ -1604,6 +1574,11 @@ bool ContentSecurityPolicy::allowScriptFromSource(const KURL& url, ContentSecuri
     return isAllowedByAllWithURL<&CSPDirectiveList::allowScriptFromSource>(m_policies, url, reportingStatus);
 }
 
+bool ContentSecurityPolicy::allowScriptNonce(const String& nonce) const
+{
+    return isAllowedByAllWithNonce<&CSPDirectiveList::allowScriptNonce>(m_policies, nonce);
+}
+
 bool ContentSecurityPolicy::allowObjectFromSource(const KURL& url, ContentSecurityPolicy::ReportingStatus reportingStatus) const
 {
     return isAllowedByAllWithURL<&CSPDirectiveList::allowObjectFromSource>(m_policies, url, reportingStatus);