1 files changed, 217 insertions, 0 deletions
diff --git a/dom/security/nsCSPParser.h b/dom/security/nsCSPParser.h
new file mode 100644
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+++ b/dom/security/nsCSPParser.h
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+/* -*- 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/. */
+
+#ifndef nsCSPParser_h___
+#define nsCSPParser_h___
+
+#include "nsCSPUtils.h"
+#include "nsCSPContext.h"
+#include "nsIURI.h"
+#include "PolicyTokenizer.h"
+
+bool isNumberToken(char16_t aSymbol);
+bool isValidHexDig(char16_t aHexDig);
+
+// clang-format off
+const char16_t COLON        = ':';
+const char16_t SEMICOLON    = ';';
+const char16_t SLASH        = '/';
+const char16_t PLUS         = '+';
+const char16_t DASH         = '-';
+const char16_t DOT          = '.';
+const char16_t UNDERLINE    = '_';
+const char16_t TILDE        = '~';
+const char16_t WILDCARD     = '*';
+const char16_t SINGLEQUOTE  = '\'';
+const char16_t NUMBER_SIGN  = '#';
+const char16_t QUESTIONMARK = '?';
+const char16_t PERCENT_SIGN = '%';
+const char16_t EXCLAMATION  = '!';
+const char16_t DOLLAR       = '$';
+const char16_t AMPERSAND    = '&';
+const char16_t OPENBRACE    = '(';
+const char16_t CLOSINGBRACE = ')';
+const char16_t EQUALS       = '=';
+const char16_t ATSYMBOL     = '@';
+// clang-format on
+
+class nsCSPParser {
+ public:
+  /**
+   * The CSP parser only has one publicly accessible function, which is
+   * parseContentSecurityPolicy. Internally the input string is separated into
+   * string tokens and policy() is called, which starts parsing the policy. The
+   * parser calls one function after the other according the the source-list
+   * from http://www.w3.org/TR/CSP11/#source-list. E.g., the parser can only
+   * call port() after the parser has already processed any possible host in
+   * host(), similar to a finite state machine.
+   */
+  static nsCSPPolicy* parseContentSecurityPolicy(const nsAString& aPolicyString,
+                                                 nsIURI* aSelfURI,
+                                                 bool aReportOnly,
+                                                 nsCSPContext* aCSPContext,
+                                                 bool aDeliveredViaMetaTag,
+                                                 bool aSuppressLogMessages);
+
+ private:
+  nsCSPParser(policyTokens& aTokens, nsIURI* aSelfURI,
+              nsCSPContext* aCSPContext, bool aDeliveredViaMetaTag,
+              bool aSuppressLogMessages);
+
+  ~nsCSPParser();
+
+  // Parsing the CSP using the source-list from
+  // http://www.w3.org/TR/CSP11/#source-list
+  nsCSPPolicy* policy();
+  void directive();
+  nsCSPDirective* directiveName();
+  void directiveValue(nsTArray<nsCSPBaseSrc*>& outSrcs);
+  void referrerDirectiveValue(nsCSPDirective* aDir);
+  void reportURIList(nsCSPDirective* aDir);
+  void sandboxFlagList(nsCSPDirective* aDir);
+  void sourceList(nsTArray<nsCSPBaseSrc*>& outSrcs);
+  nsCSPBaseSrc* sourceExpression();
+  nsCSPSchemeSrc* schemeSource();
+  nsCSPHostSrc* hostSource();
+  nsCSPBaseSrc* keywordSource();
+  nsCSPNonceSrc* nonceSource();
+  nsCSPHashSrc* hashSource();
+  nsCSPHostSrc* host();
+  bool hostChar();
+  bool schemeChar();
+  bool port();
+  bool path(nsCSPHostSrc* aCspHost);
+
+  bool subHost();                        // helper function to parse subDomains
+  bool atValidUnreservedChar();          // helper function to parse unreserved
+  bool atValidSubDelimChar();            // helper function to parse sub-delims
+  bool atValidPctEncodedChar();          // helper function to parse pct-encoded
+  bool subPath(nsCSPHostSrc* aCspHost);  // helper function to parse paths
+
+  inline bool atEnd() { return mCurChar >= mEndChar; }
+
+  inline bool accept(char16_t aSymbol) {
+    if (atEnd()) {
+      return false;
+    }
+    return (*mCurChar == aSymbol) && advance();
+  }
+
+  inline bool accept(bool (*aClassifier)(char16_t)) {
+    if (atEnd()) {
+      return false;
+    }
+    return (aClassifier(*mCurChar)) && advance();
+  }
+
+  inline bool peek(char16_t aSymbol) {
+    if (atEnd()) {
+      return false;
+    }
+    return *mCurChar == aSymbol;
+  }
+
+  inline bool peek(bool (*aClassifier)(char16_t)) {
+    if (atEnd()) {
+      return false;
+    }
+    return aClassifier(*mCurChar);
+  }
+
+  inline bool advance() {
+    if (atEnd()) {
+      return false;
+    }
+    mCurValue.Append(*mCurChar++);
+    return true;
+  }
+
+  inline void resetCurValue() { mCurValue.Truncate(); }
+
+  bool atEndOfPath();
+  bool atValidPathChar();
+
+  void resetCurChar(const nsAString& aToken);
+
+  void logWarningErrorToConsole(uint32_t aSeverityFlag, const char* aProperty,
+                                const nsTArray<nsString>& aParams);
+
+  /**
+   * When parsing the policy, the parser internally uses the following helper
+   * variables/members which are used/reset during parsing. The following
+   * example explains how they are used.
+   * The tokenizer separats all input into arrays of arrays of strings, which
+   * are stored in mTokens, for example:
+   *   mTokens = [ [ script-src, http://www.example.com, 'self' ], ... ]
+   *
+   * When parsing starts, mCurdir always holds the currently processed array of
+   * strings.
+   * In our example:
+   *   mCurDir = [ script-src, http://www.example.com, 'self' ]
+   *
+   * During parsing, we process/consume one string at a time of that array.
+   * We set mCurToken to the string we are currently processing; in the first
+   * case that would be: mCurToken = script-src which allows to do simple string
+   * comparisons to see if mCurToken is a valid directive.
+   *
+   * Continuing parsing, the parser consumes the next string of that array,
+   * resetting:
+   *   mCurToken = "http://www.example.com"
+   *                ^                     ^
+   *                mCurChar              mEndChar (points *after* the 'm')
+   *   mCurValue = ""
+   *
+   * After calling advance() the first time, helpers would hold the following
+   * values:
+   *   mCurToken = "http://www.example.com"
+   *                 ^                    ^
+   *                 mCurChar             mEndChar (points *after* the 'm')
+   *  mCurValue = "h"
+   *
+   * We continue parsing till all strings of one directive are consumed, then we
+   * reset mCurDir to hold the next array of strings and start the process all
+   * over.
+   */
+
+  const char16_t* mCurChar;
+  const char16_t* mEndChar;
+  nsString mCurValue;
+  nsString mCurToken;
+  nsTArray<nsString> mCurDir;
+
+  // helpers to allow invalidation of srcs within script-src and style-src
+  // if either 'strict-dynamic' or at least a hash or nonce is present.
+  bool mHasHashOrNonce;    // false, if no hash or nonce is defined
+  bool mHasAnyUnsafeEval;  // false, if no (wasm-)unsafe-eval keyword is used.
+  bool mStrictDynamic;     // false, if 'strict-dynamic' is not defined
+  nsCSPKeywordSrc* mUnsafeInlineKeywordSrc;  // null, otherwise invlidate()
+
+  // cache variables for child-src, frame-src and worker-src handling;
+  // in CSP 3 child-src is deprecated. For backwards compatibility
+  // child-src needs to restrict:
+  //   (*) frames, in case frame-src is not expicitly specified
+  //   (*) workers, in case worker-src is not expicitly specified
+  // If neither worker-src, nor child-src is present, then script-src
+  // needs to govern workers.
+  nsCSPChildSrcDirective* mChildSrc;
+  nsCSPDirective* mFrameSrc;
+  nsCSPDirective* mWorkerSrc;
+  nsCSPScriptSrcDirective* mScriptSrc;
+  nsCSPStyleSrcDirective* mStyleSrc;
+
+  // cache variable to let nsCSPHostSrc know that it's within
+  // the frame-ancestors directive.
+  bool mParsingFrameAncestorsDir;
+
+  policyTokens mTokens;
+  nsIURI* mSelfURI;
+  nsCSPPolicy* mPolicy;
+  nsCSPContext* mCSPContext;  // used for console logging
+  bool mDeliveredViaMetaTag;
+  bool mSuppressLogMessages;
+};
+
+#endif /* nsCSPParser_h___ */