The Tor Browser: security/manager/boot/src/nsSecurityHeaderParser.cpp@b8a032363ba2 (annotated)

security/manager/boot/src/nsSecurityHeaderParser.cpp@b8a032363ba2 (annotated)

security/manager/boot/src/nsSecurityHeaderParser.cpp

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* 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 "nsSecurityHeaderParser.h"
 #include "prlog.h"
 // The character classes in this file are informed by [RFC2616], Section 2.2.
 // signed char is a signed data type one byte (8 bits) wide, so its value can
 // never be greater than 127. The following implicitly makes use of this.
 // A token is one or more CHAR except CTLs or separators.
 // A CHAR is any US-ASCII character (octets 0 - 127).
 // A CTL is any US-ASCII control character (octets 0 - 31) and DEL (127).
 // A separator is one of ()<>@,;:\"/[]?={} as well as space and
 // horizontal-tab (32 and 9, respectively).
 // So, this returns true if chr is any octet 33-126 except ()<>@,;:\"/[]?={}
 bool
 IsTokenSymbol(signed char chr) {
   if (chr < 33 || chr == 127 ||
       chr == '(' || chr == ')' || chr == '<' || chr == '>' ||
       chr == '@' || chr == ',' || chr == ';' || chr == ':' ||
       chr == '"' || chr == '/' || chr == '[' || chr == ']' ||
       chr == '?' || chr == '=' || chr == '{' || chr == '}' || chr == '\\') {
     return false;
   }
   return true;
 }
 // A quoted-string consists of a quote (") followed by any amount of
 // qdtext or quoted-pair, followed by a quote.
 // qdtext is any TEXT except a quote.
 // TEXT is any 8-bit octet except CTLs, but including LWS.
 // quoted-pair is a backslash (\) followed by a CHAR.
 // So, it turns out, \ can't really be a qdtext symbol for our purposes.
 // This returns true if chr is any octet 9,10,13,32-126 except <"> or "\"
 bool
 IsQuotedTextSymbol(signed char chr) {
   return ((chr >= 32 && chr != '"' && chr != '\\' && chr != 127) ||
           chr == 0x9 || chr == 0xa || chr == 0xd);
 }
 // The octet following the "\" in a quoted pair can be anything 0-127.
 bool
 IsQuotedPairSymbol(signed char chr) {
   return (chr >= 0);
 }
 #if defined(PR_LOGGING)
 static PRLogModuleInfo *
 GetSHParserLog()
 {
   static PRLogModuleInfo *sSHParserLog;
   if (!sSHParserLog) {
     sSHParserLog = PR_NewLogModule("nsSecurityHeaderParser");
   }
   return sSHParserLog;
 }
 #endif
 #define SHPARSERLOG(args) PR_LOG(GetSHParserLog(), PR_LOG_DEBUG, args)
 nsSecurityHeaderParser::nsSecurityHeaderParser(const char *aHeader)
   : mCursor(aHeader)
   , mError(false)
 {
 }
 nsSecurityHeaderParser::~nsSecurityHeaderParser() {
   nsSecurityHeaderDirective *directive;
   while ((directive = mDirectives.popFirst())) {
     delete directive;
   }
 }
 mozilla::LinkedList<nsSecurityHeaderDirective> *
 nsSecurityHeaderParser::GetDirectives() {
   return &mDirectives;
 }
 nsresult
 nsSecurityHeaderParser::Parse() {
   MOZ_ASSERT(mDirectives.isEmpty());
   SHPARSERLOG(("trying to parse '%s'", mCursor));
   Header();
   // if we didn't consume the entire input, we were unable to parse it => error
   if (mError || *mCursor) {
     return NS_ERROR_FAILURE;
   } else {
     return NS_OK;
   }
 }
 bool
 nsSecurityHeaderParser::Accept(char aChr)
 {
   if (*mCursor == aChr) {
     Advance();
     return true;
   }
   return false;
 }
 bool
 nsSecurityHeaderParser::Accept(bool (*aClassifier) (signed char))
 {
   if (aClassifier(*mCursor)) {
     Advance();
     return true;
   }
   return false;
 }
 void
 nsSecurityHeaderParser::Expect(char aChr)
 {
   if (*mCursor != aChr) {
     mError = true;
   } else {
     Advance();
   }
 }
 void
 nsSecurityHeaderParser::Advance()
 {
   // Technically, 0 is valid in quoted-pair, but we were handed a
   // null-terminated const char *, so this doesn't handle that.
   if (*mCursor) {
     mOutput.Append(*mCursor);
     mCursor++;
   } else {
     mError = true;
   }
 }
 void
 nsSecurityHeaderParser::Header()
 {
   Directive();
   while (Accept(';')) {
     Directive();
   }
 }
 void
 nsSecurityHeaderParser::Directive()
 {
   mDirective = new nsSecurityHeaderDirective();
   LWSMultiple();
   DirectiveName();
   LWSMultiple();
   if (Accept('=')) {
     LWSMultiple();
     DirectiveValue();
     LWSMultiple();
   }
   mDirectives.insertBack(mDirective);
   SHPARSERLOG(("read directive name '%s', value '%s'",
                mDirective->mName.Data(), mDirective->mValue.Data()));
 }
 void
 nsSecurityHeaderParser::DirectiveName()
 {
   mOutput.Truncate(0);
   Token();
   mDirective->mName.Assign(mOutput);
 }
 void
 nsSecurityHeaderParser::DirectiveValue()
 {
   mOutput.Truncate(0);
   if (Accept(IsTokenSymbol)) {
     Token();
     mDirective->mValue.Assign(mOutput);
   } else if (Accept('"')) {
     // Accept advances the cursor if successful, which appends a character to
     // mOutput. The " is not part of what we want to capture, so truncate
     // mOutput again.
     mOutput.Truncate(0);
     QuotedString();
     mDirective->mValue.Assign(mOutput);
     Expect('"');
   }
 }
 void
 nsSecurityHeaderParser::Token()
 {
   while (Accept(IsTokenSymbol));
 }
 void
 nsSecurityHeaderParser::QuotedString()
 {
   while (true) {
     if (Accept(IsQuotedTextSymbol)) {
       QuotedText();
     } else if (Accept('\\')) {
       QuotedPair();
     } else {
       break;
     }
   }
 }
 void
 nsSecurityHeaderParser::QuotedText()
 {
   while (Accept(IsQuotedTextSymbol));
 }
 void
 nsSecurityHeaderParser::QuotedPair()
 {
   Accept(IsQuotedPairSymbol);
 }
 void
 nsSecurityHeaderParser::LWSMultiple()
 {
   while (true) {
     if (Accept('\r')) {
       LWSCRLF();
     } else if (Accept(' ') || Accept('\t')) {
       LWS();
     } else {
       break;
     }
   }
 }
 void
 nsSecurityHeaderParser::LWSCRLF() {
   Expect('\n');
   if (!(Accept(' ') || Accept('\t'))) {
     mError = true;
   }
   LWS();
 }
 void
 nsSecurityHeaderParser::LWS()
 {
   // Note that becaue of how we're called, we don't have to check for
   // the mandatory presense of at least one of SP or HT.
   while (Accept(' ') || Accept('\t'));
 }

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security/manager/boot/src/nsSecurityHeaderParser.cpp@b8a032363ba2 (annotated)

security/manager/boot/src/nsSecurityHeaderParser.cpp