Line data    Source code

       1             : /* This Source Code Form is subject to the terms of the Mozilla Public
       2             :  * License, v. 2.0. If a copy of the MPL was not distributed with this
       3             :  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
       4             : 
       5             : #ifndef nsSecurityHeaderParser_h
       6             : #define nsSecurityHeaderParser_h
       7             : 
       8             : #include "mozilla/LinkedList.h"
       9             : #include "nsCOMPtr.h"
      10             : #include "nsString.h"
      11             : 
      12             : // Utility class for handing back parsed directives and (optional) values
      13           0 : class nsSecurityHeaderDirective : public mozilla::LinkedListElement<nsSecurityHeaderDirective> {
      14             : public:
      15             :   nsCString mName;
      16             :   nsCString mValue;
      17             : };
      18             : 
      19             : // This class parses security-related HTTP headers like
      20             : // Strict-Transport-Security. The Augmented Backus-Naur Form syntax for this
      21             : // header is reproduced below, for reference:
      22             : //
      23             : //   Strict-Transport-Security = "Strict-Transport-Security" ":"
      24             : //                               [ directive ]  *( ";" [ directive ] )
      25             : //
      26             : //   directive                 = directive-name [ "=" directive-value ]
      27             : //   directive-name            = token
      28             : //   directive-value           = token | quoted-string
      29             : //
      30             : //   where:
      31             : //
      32             : //   token          = <token, defined in [RFC2616], Section 2.2>
      33             : //   quoted-string  = <quoted-string, defined in [RFC2616], Section 2.2>/
      34             : //
      35             : // For further reference, see [RFC6797], Section 6.1
      36             : 
      37             : class nsSecurityHeaderParser {
      38             : public:
      39             :   // The input to this class must be null-terminated, and must have a lifetime
      40             :   // greater than or equal to the lifetime of the created nsSecurityHeaderParser.
      41             :   explicit nsSecurityHeaderParser(const nsCString& aHeader);
      42             :   ~nsSecurityHeaderParser();
      43             : 
      44             :   // Only call Parse once.
      45             :   nsresult Parse();
      46             :   // The caller does not take ownership of the memory returned here.
      47             :   mozilla::LinkedList<nsSecurityHeaderDirective> *GetDirectives();
      48             : 
      49             : private:
      50             :   bool Accept(char aChr);
      51             :   bool Accept(bool (*aClassifier) (signed char));
      52             :   void Expect(char aChr);
      53             :   void Advance();
      54             :   void Header();         // header = [ directive ] *( ";" [ directive ] )
      55             :   void Directive();      // directive = directive-name [ "=" directive-value ]
      56             :   void DirectiveName();  // directive-name = token
      57             :   void DirectiveValue(); // directive-value = token | quoted-string
      58             :   void Token();          // token = 1*<any CHAR except CTLs or separators>
      59             :   void QuotedString();   // quoted-string = (<"> *( qdtext | quoted-pair ) <">)
      60             :   void QuotedText();     // qdtext = <any TEXT except <"> and "\">
      61             :   void QuotedPair();     // quoted-pair = "\" CHAR
      62             : 
      63             :                          // LWS = [CRLF] 1*( SP | HT )
      64             :   void LWSMultiple();    // Handles *( LWS )
      65             :   void LWSCRLF();        // Handles the [CRLF] part of LWS
      66             :   void LWS();            // Handles the 1*( SP | HT ) part of LWS
      67             : 
      68             :   mozilla::LinkedList<nsSecurityHeaderDirective> mDirectives;
      69             :   const char *mCursor;
      70             :   nsSecurityHeaderDirective *mDirective;
      71             : 
      72             :   nsCString mOutput;
      73             :   bool mError;
      74             : };
      75             : 
      76             : #endif // nsSecurityHeaderParser_h