1 files changed, 206 insertions, 0 deletions
diff --git a/security/manager/ssl/nsSecurityHeaderParser.cpp b/security/manager/ssl/nsSecurityHeaderParser.cpp
new file mode 100644
index 0000000000..d9d9d48bc0
--- /dev/null
+++ b/security/manager/ssl/nsSecurityHeaderParser.cpp
@@ -0,0 +1,206 @@
+/* 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 "mozilla/Logging.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); }
+
+static mozilla::LazyLogModule sSHParserLog("nsSecurityHeaderParser");
+
+#define SHPARSERLOG(args) MOZ_LOG(sSHParserLog, mozilla::LogLevel::Debug, args)
+
+nsSecurityHeaderParser::nsSecurityHeaderParser(const nsCString& aHeader)
+    : mCursor(aHeader.get()), mDirective(nullptr), 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'))
+    ;
+}