/// <summary>
/// Initializes a new instance of the <see cref="EntityTagHeaderValue"/>.
/// </summary>
/// <param name="tag">A <see cref="StringSegment"/> that contains an <see cref="EntityTagHeaderValue"/>.</param>
/// <param name="isWeak">A value that indicates if this entity-tag header is a weak validator.</param>
public EntityTagHeaderValue(StringSegment tag, bool isWeak)
{
if (StringSegment.IsNullOrEmpty(tag))
{
throw new ArgumentException("An empty string is not allowed.", nameof(tag));
}
if (!isWeak && StringSegment.Equals(tag, "*", StringComparison.Ordinal))
{
// * is valid, but W/* isn't.
_tag = tag;
}
else if ((HttpRuleParser.GetQuotedStringLength(tag, 0, out var length) != HttpParseResult.Parsed) ||
(length != tag.Length))
{
// Note that we don't allow 'W/' prefixes for weak ETags in the 'tag' parameter. If the user wants to
// add a weak ETag, they can set 'isWeak' to true.
throw new FormatException("Invalid ETag name");
}
_tag = tag;
_isWeak = isWeak;
}
// Encode a string using RFC 5987 encoding.
// encoding'lang'PercentEncodedSpecials
internal static string Encode5987(string input)
{
// Encode a string using RFC 5987 encoding.
// encoding'lang'PercentEncodedSpecials
var builder = new ValueStringBuilder(stackalloc char[256]);
byte[] utf8bytes = ArrayPool <byte> .Shared.Rent(Encoding.UTF8.GetMaxByteCount(input.Length));
int utf8length = Encoding.UTF8.GetBytes(input, 0, input.Length, utf8bytes, 0);
builder.Append("utf-8\'\'");
for (int i = 0; i < utf8length; i++)
{
byte utf8byte = utf8bytes[i];
// attr-char = ALPHA / DIGIT / "!" / "#" / "$" / "&" / "+" / "-" / "." / "^" / "_" / "`" / "|" / "~"
// ; token except ( "*" / "'" / "%" )
if (utf8byte > 0x7F) // Encodes as multiple utf-8 bytes
{
AddHexEscaped(utf8byte, ref builder);
}
else if (!HttpRuleParser.IsTokenChar((char)utf8byte) || utf8byte == '*' || utf8byte == '\'' || utf8byte == '%')
{
// ASCII - Only one encoded byte.
AddHexEscaped(utf8byte, ref builder);
}
else
{
builder.Append((char)utf8byte);
}
}
Array.Clear(utf8bytes, 0, utf8length);
ArrayPool <byte> .Shared.Return(utf8bytes);
return(builder.ToString());
}
/// <summary>
/// Check if a target directive exists among the set of given cache control directives.
/// </summary>
/// <param name="cacheControlDirectives">
/// The <see cref="StringValues"/> containing the set of cache control directives.
/// </param>
/// <param name="targetDirectives">
/// The target cache control directives to look for.
/// </param>
/// <returns>
/// <code>true</code> if <paramref name="targetDirectives"/> is contained in <paramref name="cacheControlDirectives"/>;
/// otherwise, <code>false</code>.
/// </returns>
public static bool ContainsCacheDirective(StringValues cacheControlDirectives, string targetDirectives)
{
if (StringValues.IsNullOrEmpty(cacheControlDirectives) || string.IsNullOrEmpty(targetDirectives))
{
return(false);
}
for (var i = 0; i < cacheControlDirectives.Count; i++)
{
// Trim leading white space
var current = HttpRuleParser.GetWhitespaceLength(cacheControlDirectives[i], 0);
while (current < cacheControlDirectives[i].Length)
{
var initial = current;
var tokenLength = HttpRuleParser.GetTokenLength(cacheControlDirectives[i], current);
if (tokenLength == targetDirectives.Length &&
string.Compare(cacheControlDirectives[i], current, targetDirectives, 0, tokenLength, StringComparison.OrdinalIgnoreCase) == 0)
{
// Token matches target value
return(true);
}
current = AdvanceCacheDirectiveIndex(current + tokenLength, cacheControlDirectives[i]);
// Ensure index was advanced
if (current <= initial)
{
Debug.Assert(false, $"Index '{nameof(current)}' not advanced, this is a bug.");
return(false);
}
}
}
return(false);
}
public KnownHeader(string name, HttpHeaderType headerType, HttpHeaderParser parser, string[] knownValues = null, int?http2StaticTableIndex = null)
{
Debug.Assert(!string.IsNullOrEmpty(name));
Debug.Assert(HttpRuleParser.GetTokenLength(name, 0) == name.Length);
Debug.Assert((headerType == HttpHeaderType.Custom) == (parser == null));
Debug.Assert(knownValues == null || headerType != HttpHeaderType.Custom);
Name = name;
HeaderType = headerType;
Parser = parser;
KnownValues = knownValues;
Http2EncodedName = http2StaticTableIndex.HasValue ?
HPackEncoder.EncodeLiteralHeaderFieldWithoutIndexingToAllocatedArray(http2StaticTableIndex.GetValueOrDefault()) :
HPackEncoder.EncodeLiteralHeaderFieldWithoutIndexingNewNameToAllocatedArray(name);
var asciiBytesWithColonSpace = new byte[name.Length + 2]; // + 2 for ':' and ' '
int asciiBytes = Encoding.ASCII.GetBytes(name, asciiBytesWithColonSpace);
Debug.Assert(asciiBytes == name.Length);
asciiBytesWithColonSpace[asciiBytesWithColonSpace.Length - 2] = (byte)':';
asciiBytesWithColonSpace[asciiBytesWithColonSpace.Length - 1] = (byte)' ';
AsciiBytesWithColonSpace = asciiBytesWithColonSpace;
}
private static bool TryReadAgent(string input, int startIndex, ref int current, out string agent)
{
agent = null;
int agentLength = HttpRuleParser.GetHostLength(input, startIndex, true, out agent);
if (agentLength == 0)
{
return(false);
}
current = current + agentLength;
int whitespaceLength = HttpRuleParser.GetWhitespaceLength(input, current);
current = current + whitespaceLength;
// At least one whitespace required after <agent>. Also make sure we have characters left for <text>
if ((whitespaceLength == 0) || (current == input.Length))
{
return(false);
}
return(true);
}
private static void CheckValueFormat(string?value)
{
// Either value is null/empty or a valid token/quoted string https://tools.ietf.org/html/rfc7230#section-3.2.6
if (string.IsNullOrEmpty(value))
{
return;
}
// Trailing/leading space are not allowed
if (value[0] == ' ' || value[0] == '\t' || value[^ 1] == ' ' || value[^ 1] == '\t')
{
throw new FormatException(SR.Format(System.Globalization.CultureInfo.InvariantCulture, SR.net_http_headers_invalid_value, value));
}
// If it's not a token we check if it's a valid quoted string
if (HttpRuleParser.GetTokenLength(value, 0) == 0)
{
HttpParseResult parseResult = HttpRuleParser.GetQuotedStringLength(value, 0, out int valueLength);
if ((parseResult == HttpParseResult.Parsed && valueLength != value.Length) || parseResult != HttpParseResult.Parsed)
{
throw new FormatException(SR.Format(System.Globalization.CultureInfo.InvariantCulture, SR.net_http_headers_invalid_value, value));
}
}
}
// Returns input for decoding failures, as the content might not be encoded
private StringSegment EncodeAndQuoteMime(StringSegment input)
{
var result = input;
var needsQuotes = false;
// Remove bounding quotes, they'll get re-added later
if (IsQuoted(result))
{
result = result.Subsegment(1, result.Length - 2);
needsQuotes = true;
}
if (RequiresEncoding(result))
{
// EncodeMimeWithQuotes will Base64 encode any quotes in the input, and surround the payload in quotes
// so there is no need to add quotes
needsQuotes = false;
result = EncodeMimeWithQuotes(result); // "=?utf-8?B?asdfasdfaesdf?="
}
else if (!needsQuotes && HttpRuleParser.GetTokenLength(result, 0) != result.Length)
{
needsQuotes = true;
}
if (needsQuotes)
{
if (result.IndexOfAny(EscapeChars) != -1)
{
// '\' and '"' must be escaped in a quoted string
result = result.ToString().Replace(@"\", @"\\").Replace(@"""", @"\""");
}
// Re-add quotes "value"
result = string.Format(CultureInfo.InvariantCulture, "\"{0}\"", result);
}
return(result);
}
internal static int GetDispositionTypeLength(
string input,
int startIndex,
out object parsedValue)
{
parsedValue = (object)null;
if (string.IsNullOrEmpty(input) || startIndex >= input.Length)
{
return(0);
}
string dispositionType = (string)null;
int expressionLength = ContentDispositionHeaderValue.GetDispositionTypeExpressionLength(input, startIndex, out dispositionType);
if (expressionLength == 0)
{
return(0);
}
int startIndex1 = startIndex + expressionLength;
int index = startIndex1 + HttpRuleParser.GetWhitespaceLength(input, startIndex1);
ContentDispositionHeaderValue dispositionHeaderValue = new ContentDispositionHeaderValue();
dispositionHeaderValue._dispositionType = dispositionType;
if (index < input.Length && input[index] == ';')
{
int startIndex2 = index + 1;
int nameValueListLength = NameValueHeaderValue.GetNameValueListLength(input, startIndex2, ';', (ObjectCollection <NameValueHeaderValue>)dispositionHeaderValue.Parameters);
if (nameValueListLength == 0)
{
return(0);
}
parsedValue = (object)dispositionHeaderValue;
return(startIndex2 + nameValueListLength - startIndex);
}
parsedValue = (object)dispositionHeaderValue;
return(index - startIndex);
}
internal static bool IsInputEncoded5987(string input, out string output)
{
// Encode a string using RFC 5987 encoding.
// encoding'lang'PercentEncodedSpecials
bool wasEncoded = false;
StringBuilder builder = StringBuilderCache.Acquire();
builder.Append("utf-8\'\'");
foreach (char c in input)
{
// attr-char = ALPHA / DIGIT / "!" / "#" / "$" / "&" / "+" / "-" / "." / "^" / "_" / "`" / "|" / "~"
// ; token except ( "*" / "'" / "%" )
if (c > 0x7F) // Encodes as multiple utf-8 bytes
{
byte[] bytes = Encoding.UTF8.GetBytes(c.ToString());
foreach (byte b in bytes)
{
AddHexEscaped((char)b, builder);
wasEncoded = true;
}
}
else if (!HttpRuleParser.IsTokenChar(c) || c == '*' || c == '\'' || c == '%')
{
// ASCII - Only one encoded byte.
AddHexEscaped(c, builder);
wasEncoded = true;
}
else
{
builder.Append(c);
}
}
output = StringBuilderCache.GetStringAndRelease(builder);
return(wasEncoded);
}
private static bool TryGetLengthLength(string input, ref int current, out int lengthLength)
{
lengthLength = 0;
if (input[current] == '*')
{
current++;
}
else
{
// Parse length value: <length> in '<unit> <from>-<to>/<length>'
lengthLength = HttpRuleParser.GetNumberLength(input, current, false);
if ((lengthLength == 0) || (lengthLength > HttpRuleParser.MaxInt64Digits))
{
return(false);
}
current = current + lengthLength;
}
current = current + HttpRuleParser.GetWhitespaceLength(input, current);
return(true);
}
private static int GetRangeConditionLength(StringSegment input, int startIndex, out RangeConditionHeaderValue?parsedValue)
{
Contract.Requires(startIndex >= 0);
parsedValue = null;
// Make sure we have at least 2 characters
if (StringSegment.IsNullOrEmpty(input) || (startIndex + 1 >= input.Length))
{
return(0);
}
var current = startIndex;
// Caller must remove leading whitespaces.
DateTimeOffset date = DateTimeOffset.MinValue;
EntityTagHeaderValue?entityTag = null;
// Entity tags are quoted strings optionally preceded by "W/". By looking at the first two character we
// can determine whether the string is en entity tag or a date.
var firstChar = input[current];
var secondChar = input[current + 1];
if ((firstChar == '\"') || (((firstChar == 'w') || (firstChar == 'W')) && (secondChar == '/')))
{
// trailing whitespaces are removed by GetEntityTagLength()
var entityTagLength = EntityTagHeaderValue.GetEntityTagLength(input, current, out entityTag);
if (entityTagLength == 0)
{
return(0);
}
current = current + entityTagLength;
// RangeConditionHeaderValue only allows 1 value. There must be no delimiter/other chars after an
// entity tag.
if (current != input.Length)
{
return(0);
}
}
else
{
if (!HttpRuleParser.TryStringToDate(input.Subsegment(current), out date))
{
return(0);
}
// If we got a valid date, then the parser consumed the whole string (incl. trailing whitespaces).
current = input.Length;
}
parsedValue = new RangeConditionHeaderValue();
if (entityTag == null)
{
parsedValue._lastModified = date;
}
else
{
parsedValue._entityTag = entityTag;
}
return(current - startIndex);
}
private static int GetProtocolEndIndex(string input, int startIndex, out string protocolName,
out string protocolVersion)
{
// We have a string of the form '[<protocolName>/]<protocolVersion> <receivedBy> [<comment>]'. The first
// token may either be the protocol name or protocol version. We'll only find out after reading the token
// and by looking at the following character: If it is a '/' we just parsed the protocol name, otherwise
// the protocol version.
protocolName = null;
protocolVersion = null;
int current = startIndex;
int protocolVersionOrNameLength = HttpRuleParser.GetTokenLength(input, current);
if (protocolVersionOrNameLength == 0)
{
return(0);
}
current = startIndex + protocolVersionOrNameLength;
int whitespaceLength = HttpRuleParser.GetWhitespaceLength(input, current);
current = current + whitespaceLength;
if (current == input.Length)
{
return(0);
}
if (input[current] == '/')
{
// We parsed the protocol name
protocolName = input.Substring(startIndex, protocolVersionOrNameLength);
current++; // skip the '/' delimiter
current = current + HttpRuleParser.GetWhitespaceLength(input, current);
protocolVersionOrNameLength = HttpRuleParser.GetTokenLength(input, current);
if (protocolVersionOrNameLength == 0)
{
return(0); // We have a string "<token>/" followed by non-token chars. This is invalid.
}
protocolVersion = input.Substring(current, protocolVersionOrNameLength);
current = current + protocolVersionOrNameLength;
whitespaceLength = HttpRuleParser.GetWhitespaceLength(input, current);
current = current + whitespaceLength;
}
else
{
protocolVersion = input.Substring(startIndex, protocolVersionOrNameLength);
}
if (whitespaceLength == 0)
{
return(0); // We were able to parse [<protocolName>/]<protocolVersion> but it wasn't followed by a WS
}
return(current);
}
internal static int GetViaLength(string input, int startIndex, out object parsedValue)
{
Debug.Assert(startIndex >= 0);
parsedValue = null;
if (string.IsNullOrEmpty(input) || (startIndex >= input.Length))
{
return(0);
}
// Read <protocolName> and <protocolVersion> in '[<protocolName>/]<protocolVersion> <receivedBy> [<comment>]'
string protocolName = null;
string protocolVersion = null;
int current = GetProtocolEndIndex(input, startIndex, out protocolName, out protocolVersion);
// If we reached the end of the string after reading protocolName/Version we return (we expect at least
// <receivedBy> to follow). If reading protocolName/Version read 0 bytes, we return.
if ((current == startIndex) || (current == input.Length))
{
return(0);
}
Debug.Assert(protocolVersion != null);
// Read <receivedBy> in '[<protocolName>/]<protocolVersion> <receivedBy> [<comment>]'
string receivedBy = null;
int receivedByLength = HttpRuleParser.GetHostLength(input, current, true, out receivedBy);
if (receivedByLength == 0)
{
return(0);
}
current = current + receivedByLength;
current = current + HttpRuleParser.GetWhitespaceLength(input, current);
string comment = null;
if ((current < input.Length) && (input[current] == '('))
{
// We have a <comment> in '[<protocolName>/]<protocolVersion> <receivedBy> [<comment>]'
int commentLength = 0;
if (HttpRuleParser.GetCommentLength(input, current, out commentLength) != HttpParseResult.Parsed)
{
return(0); // We found a '(' character but it wasn't a valid comment. Abort.
}
comment = input.Substring(current, commentLength);
current = current + commentLength;
current = current + HttpRuleParser.GetWhitespaceLength(input, current);
}
ViaHeaderValue result = new ViaHeaderValue();
result._protocolVersion = protocolVersion;
result._protocolName = protocolName;
result._receivedBy = receivedBy;
result._comment = comment;
parsedValue = result;
return(current - startIndex);
}
internal static int GetRetryConditionLength(string?input, int startIndex, out object?parsedValue)
{
Debug.Assert(startIndex >= 0);
parsedValue = null;
if (string.IsNullOrEmpty(input) || (startIndex >= input.Length))
{
return(0);
}
int current = startIndex;
// Caller must remove leading whitespace.
DateTimeOffset date = DateTimeOffset.MinValue;
int deltaSeconds = -1; // use -1 to indicate that the value was not set. 'delta' values are always >=0
// We either have a timespan or a date/time value. Determine which one we have by looking at the first char.
// If it is a number, we have a timespan, otherwise we assume we have a date.
char firstChar = input[current];
if ((firstChar >= '0') && (firstChar <= '9'))
{
int deltaStartIndex = current;
int deltaLength = HttpRuleParser.GetNumberLength(input, current, false);
// The value must be in the range 0..2^31
if ((deltaLength == 0) || (deltaLength > HttpRuleParser.MaxInt32Digits))
{
return(0);
}
current = current + deltaLength;
current = current + HttpRuleParser.GetWhitespaceLength(input, current);
// RetryConditionHeaderValue only allows 1 value. There must be no delimiter/other chars after 'delta'
if (current != input.Length)
{
return(0);
}
if (!HeaderUtilities.TryParseInt32(input, deltaStartIndex, deltaLength, out deltaSeconds))
{
return(0); // int.TryParse() may return 'false' if the value has 10 digits and is > Int32.MaxValue.
}
}
else
{
if (!HttpDateParser.TryParse(input.AsSpan(current), out date))
{
return(0);
}
// If we got a valid date, then the parser consumed the whole string (incl. trailing whitespace).
current = input.Length;
}
RetryConditionHeaderValue result = new RetryConditionHeaderValue();
if (deltaSeconds == -1) // we didn't change delta, so we must have found a date.
{
result._date = date;
}
else
{
result._delta = new TimeSpan(0, 0, deltaSeconds);
}
parsedValue = result;
return(current - startIndex);
}
internal static int GetRangeItemLength(string?input, int startIndex, out RangeItemHeaderValue?parsedValue)
{
Debug.Assert(startIndex >= 0);
// This parser parses number ranges: e.g. '1-2', '1-', '-2'.
parsedValue = null;
if (string.IsNullOrEmpty(input) || (startIndex >= input.Length))
{
return(0);
}
// Caller must remove leading whitespace. If not, we'll return 0.
int current = startIndex;
// Try parse the first value of a value pair.
int fromStartIndex = current;
int fromLength = HttpRuleParser.GetNumberLength(input, current, false);
if (fromLength > HttpRuleParser.MaxInt64Digits)
{
return(0);
}
current = current + fromLength;
current = current + HttpRuleParser.GetWhitespaceLength(input, current);
// After the first value, the '-' character must follow.
if ((current == input.Length) || (input[current] != '-'))
{
// We need a '-' character otherwise this can't be a valid range.
return(0);
}
current++; // skip the '-' character
current = current + HttpRuleParser.GetWhitespaceLength(input, current);
int toStartIndex = current;
int toLength = 0;
// If we didn't reach the end of the string, try parse the second value of the range.
if (current < input.Length)
{
toLength = HttpRuleParser.GetNumberLength(input, current, false);
if (toLength > HttpRuleParser.MaxInt64Digits)
{
return(0);
}
current = current + toLength;
current = current + HttpRuleParser.GetWhitespaceLength(input, current);
}
if ((fromLength == 0) && (toLength == 0))
{
return(0); // At least one value must be provided in order to be a valid range.
}
// Try convert first value to int64
long from = 0;
if ((fromLength > 0) && !HeaderUtilities.TryParseInt64(input, fromStartIndex, fromLength, out from))
{
return(0);
}
// Try convert second value to int64
long to = 0;
if ((toLength > 0) && !HeaderUtilities.TryParseInt64(input, toStartIndex, toLength, out to))
{
return(0);
}
// 'from' must not be greater than 'to'
if ((fromLength > 0) && (toLength > 0) && (from > to))
{
return(0);
}
parsedValue = new RangeItemHeaderValue((fromLength == 0 ? (long?)null : (long?)from),
(toLength == 0 ? (long?)null : (long?)to));
return(current - startIndex);
}
public void IsTokenChar_ValidTokenChars_ConsideredValid(char token)
{
Assert.True(HttpRuleParser.IsTokenChar(token));
}
public void GetNumberLength_SetOfInvalidNumbers_ReturnsZero()
{
Assert.Equal(0, HttpRuleParser.GetNumberLength(".456", 0, true));
Assert.Equal(0, HttpRuleParser.GetNumberLength("-1", 0, true));
Assert.Equal(0, HttpRuleParser.GetNumberLength("a", 0, true));
}
internal static int GetEntityTagLength(string input, int startIndex, out EntityTagHeaderValue parsedValue)
{
Contract.Requires(startIndex >= 0);
parsedValue = null;
if (string.IsNullOrEmpty(input) || (startIndex >= input.Length))
{
return(0);
}
// Caller must remove leading whitespaces. If not, we'll return 0.
bool isWeak = false;
int current = startIndex;
char firstChar = input[startIndex];
if (firstChar == '*')
{
// We have '*' value, indicating "any" ETag.
parsedValue = Any;
current++;
}
else
{
// The RFC defines 'W/' as prefix, but we'll be flexible and also accept lower-case 'w'.
if ((firstChar == 'W') || (firstChar == 'w'))
{
current++;
// We need at least 3 more chars: the '/' character followed by two quotes.
if ((current + 2 >= input.Length) || (input[current] != '/'))
{
return(0);
}
isWeak = true;
current++; // we have a weak-entity tag.
current = current + HttpRuleParser.GetWhitespaceLength(input, current);
}
int tagStartIndex = current;
int tagLength = 0;
if (HttpRuleParser.GetQuotedStringLength(input, current, out tagLength) != HttpParseResult.Parsed)
{
return(0);
}
parsedValue = new EntityTagHeaderValue();
if (tagLength == input.Length)
{
// Most of the time we'll have strong ETags without leading/trailing whitespaces.
Debug.Assert(startIndex == 0);
Debug.Assert(!isWeak);
parsedValue._tag = input;
parsedValue._isWeak = false;
}
else
{
parsedValue._tag = input.Substring(tagStartIndex, tagLength);
parsedValue._isWeak = isWeak;
}
current = current + tagLength;
}
current = current + HttpRuleParser.GetWhitespaceLength(input, current);
return(current - startIndex);
}
protected override int GetParsedValueLength(string value, int startIndex, object?storeValue,
out object?parsedValue)
{
Debug.Assert(startIndex >= 0);
Debug.Assert(startIndex < value.Length);
if (string.IsNullOrEmpty(value))
{
parsedValue = null;
return(0);
}
int idx = startIndex;
if (!TryReadPercentEncodedAlpnProtocolName(value, idx, out string?alpnProtocolName, out int alpnProtocolNameLength))
{
parsedValue = null;
return(0);
}
idx += alpnProtocolNameLength;
if (alpnProtocolName == "clear")
{
if (idx != value.Length)
{
// Clear has no parameters and should be the only Alt-Svc value present, so there should be nothing after it.
parsedValue = null;
return(0);
}
parsedValue = AltSvcHeaderValue.Clear;
return(idx - startIndex);
}
if (idx == value.Length || value[idx++] != '=')
{
parsedValue = null;
return(0);
}
if (!TryReadQuotedAltAuthority(value, idx, out string?altAuthorityHost, out int altAuthorityPort, out int altAuthorityLength))
{
parsedValue = null;
return(0);
}
idx += altAuthorityLength;
// Parse parameters: *( OWS ";" OWS parameter )
int? maxAge = null;
bool persist = false;
while (idx != value.Length)
{
// Skip OWS before semicolon.
while (idx != value.Length && IsOptionalWhiteSpace(value[idx]))
{
++idx;
}
if (idx == value.Length)
{
parsedValue = null;
return(0);
}
char ch = value[idx];
if (ch == ',')
{
// Multi-value header: return this value; will get called again to parse the next.
break;
}
if (ch != ';')
{
// Expecting parameters starting with semicolon; fail out.
parsedValue = null;
return(0);
}
++idx;
// Skip OWS after semicolon / before value.
while (idx != value.Length && IsOptionalWhiteSpace(value[idx]))
{
++idx;
}
// Get the parameter key length.
int tokenLength = HttpRuleParser.GetTokenLength(value, idx);
if (tokenLength == 0)
{
parsedValue = null;
return(0);
}
if ((idx + tokenLength) >= value.Length || value[idx + tokenLength] != '=')
{
parsedValue = null;
return(0);
}
if (tokenLength == 2 && value[idx] == 'm' && value[idx + 1] == 'a')
{
// Parse "ma" (Max Age).
idx += 3; // Skip "ma="
if (!TryReadTokenOrQuotedInt32(value, idx, out int maxAgeTmp, out int parameterLength))
{
parsedValue = null;
return(0);
}
if (maxAge == null)
{
maxAge = maxAgeTmp;
}
else
{
// RFC makes it unclear what to do if a duplicate parameter is found. For now, take the minimum.
maxAge = Math.Min(maxAge.GetValueOrDefault(), maxAgeTmp);
}
idx += parameterLength;
}
else if (value.AsSpan(idx).StartsWith("persist="))
{
idx += 8; // Skip "persist="
if (TryReadTokenOrQuotedInt32(value, idx, out int persistInt, out int parameterLength))
{
persist = persistInt == 1;
}
else if (!TrySkipTokenOrQuoted(value, idx, out parameterLength))
{
// Cold path: unsupported value, just skip the parameter.
parsedValue = null;
return(0);
}
idx += parameterLength;
}
internal static int GetAuthenticationLength(string input, int startIndex, out object parsedValue)
{
Contract.Requires(startIndex >= 0);
parsedValue = null;
if (string.IsNullOrEmpty(input) || (startIndex >= input.Length))
{
return(0);
}
// Parse the scheme string: <scheme> in '<scheme> <parameter>'
int schemeLength = HttpRuleParser.GetTokenLength(input, startIndex);
if (schemeLength == 0)
{
return(0);
}
AuthenticationHeaderValue result = new AuthenticationHeaderValue();
result.scheme = input.Substring(startIndex, schemeLength);
int current = startIndex + schemeLength;
int whitespaceLength = HttpRuleParser.GetWhitespaceLength(input, current);
current = current + whitespaceLength;
if ((current == input.Length) || (input[current] == ','))
{
// If we only have a scheme followed by whitespaces, we're done.
parsedValue = result;
return(current - startIndex);
}
// We need at least one space between the scheme and parameters. If there are no whitespaces, then we must
// have reached the end of the string (i.e. scheme-only string).
if (whitespaceLength == 0)
{
return(0);
}
// If we get here, we have a <scheme> followed by a whitespace. Now we expect the following:
// '<scheme> <blob>[,<name>=<value>]*[, <otherscheme>...]*': <blob> potentially contains one
// or more '=' characters, optionally followed by additional name/value pairs, optionally followed by
// other schemes. <blob> may be a quoted string.
// We look at the value after ',': if it is <token>=<value> then we have a parameter for <scheme>.
// If we have either a <token>-only or <token><whitespace><blob> then we have another scheme.
int parameterStartIndex = current;
int parameterEndIndex = current;
if (!TrySkipFirstBlob(input, ref current, ref parameterEndIndex))
{
return(0);
}
if (current < input.Length)
{
if (!TryGetParametersEndIndex(input, ref current, ref parameterEndIndex))
{
return(0);
}
}
result.parameter = input.Substring(parameterStartIndex, parameterEndIndex - parameterStartIndex + 1);
parsedValue = result;
return(current - startIndex);
}
public KnownHeader(string name, int?http2StaticTableIndex = null, int?http3StaticTableIndex = null) :
this(name, HttpHeaderType.Custom, parser : null, knownValues : null, http2StaticTableIndex, http3StaticTableIndex)
{
Debug.Assert(!string.IsNullOrEmpty(name));
Debug.Assert(name[0] == ':' || HttpRuleParser.GetTokenLength(name, 0) == name.Length);
}
internal static int GetContentRangeLength(string input, int startIndex, out object parsedValue)
{
Contract.Requires(startIndex >= 0);
parsedValue = null;
if (string.IsNullOrEmpty(input) || (startIndex >= input.Length))
{
return(0);
}
// Parse the unit string: <unit> in '<unit> <from>-<to>/<length>'
int unitLength = HttpRuleParser.GetTokenLength(input, startIndex);
if (unitLength == 0)
{
return(0);
}
string unit = input.Substring(startIndex, unitLength);
int current = startIndex + unitLength;
int separatorLength = HttpRuleParser.GetWhitespaceLength(input, current);
if (separatorLength == 0)
{
return(0);
}
current = current + separatorLength;
if (current == input.Length)
{
return(0);
}
// Read range values <from> and <to> in '<unit> <from>-<to>/<length>'
int fromStartIndex = current;
int fromLength = 0;
int toStartIndex = 0;
int toLength = 0;
if (!TryGetRangeLength(input, ref current, out fromLength, out toStartIndex, out toLength))
{
return(0);
}
// After the range is read we expect the length separator '/'
if ((current == input.Length) || (input[current] != '/'))
{
return(0);
}
current++; // Skip '/' separator
current = current + HttpRuleParser.GetWhitespaceLength(input, current);
if (current == input.Length)
{
return(0);
}
// We may not have a length (e.g. 'bytes 1-2/*'). But if we do, parse the length now.
int lengthStartIndex = current;
int lengthLength = 0;
if (!TryGetLengthLength(input, ref current, out lengthLength))
{
return(0);
}
if (!TryCreateContentRange(input, unit, fromStartIndex, fromLength, toStartIndex, toLength,
lengthStartIndex, lengthLength, out parsedValue))
{
return(0);
}
return(current - startIndex);
}
private static bool TrySetOptionalTokenList(NameValueHeaderValue nameValue, ref bool boolField,
ref ObjectCollection <string> destination)
{
Debug.Assert(nameValue != null);
if (nameValue.Value == null)
{
boolField = true;
return(true);
}
// We need the string to be at least 3 chars long: 2x quotes and at least 1 character. Also make sure we
// have a quoted string. Note that NameValueHeaderValue will never have leading/trailing whitespace.
string valueString = nameValue.Value;
if ((valueString.Length < 3) || (valueString[0] != '\"') || (valueString[valueString.Length - 1] != '\"'))
{
return(false);
}
// We have a quoted string. Now verify that the string contains a list of valid tokens separated by ','.
int current = 1; // skip the initial '"' character.
int maxLength = valueString.Length - 1; // -1 because we don't want to parse the final '"'.
bool separatorFound = false;
int originalValueCount = destination == null ? 0 : destination.Count;
while (current < maxLength)
{
current = HeaderUtilities.GetNextNonEmptyOrWhitespaceIndex(valueString, current, true,
out separatorFound);
if (current == maxLength)
{
break;
}
int tokenLength = HttpRuleParser.GetTokenLength(valueString, current);
if (tokenLength == 0)
{
// We already skipped whitespace and separators. If we don't have a token it must be an invalid
// character.
return(false);
}
if (destination == null)
{
destination = new ObjectCollection <string>(s_checkIsValidToken);
}
destination.Add(valueString.Substring(current, tokenLength));
current = current + tokenLength;
}
// After parsing a valid token list, we expect to have at least one value
if ((destination != null) && (destination.Count > originalValueCount))
{
boolField = true;
return(true);
}
return(false);
}
public override string ToString(object value)
{
Debug.Assert(value is DateTimeOffset);
return(HttpRuleParser.DateToString((DateTimeOffset)value));
}
private static void AssertGetTokenLength(string input, int startIndex, int expectedLength)
{
Assert.Equal(expectedLength, HttpRuleParser.GetTokenLength(input, startIndex));
}
public static bool TryParseDate(StringSegment input, out DateTimeOffset result)
{
return(HttpRuleParser.TryStringToDate(input, out result));
}
public void IsTokenChar_InvalidTokenChars_ConsideredInvalid(char token)
{
Assert.False(HttpRuleParser.IsTokenChar(token));
}
public KnownHeader(string name) : this(name, HttpHeaderType.Custom, null)
{
Debug.Assert(!string.IsNullOrEmpty(name));
Debug.Assert(HttpRuleParser.GetTokenLength(name, 0) == name.Length);
}
internal static int GetAuthenticationLength(string input, int startIndex, out object parsedValue)
{
Debug.Assert(startIndex >= 0);
parsedValue = null;
if (string.IsNullOrEmpty(input) || (startIndex >= input.Length))
{
return(0);
}
// Parse the scheme string: <scheme> in '<scheme> <parameter>'
int schemeLength = HttpRuleParser.GetTokenLength(input, startIndex);
if (schemeLength == 0)
{
return(0);
}
var result = new AuthenticationHeaderValue();
string targetScheme = null;
switch (schemeLength)
{
// Avoid allocating a scheme string for the most common cases.
case 5: targetScheme = "Basic"; break;
case 6: targetScheme = "Digest"; break;
case 4: targetScheme = "NTLM"; break;
case 9: targetScheme = "Negotiate"; break;
}
result._scheme = targetScheme != null && string.CompareOrdinal(input, startIndex, targetScheme, 0, schemeLength) == 0 ?
targetScheme :
input.Substring(startIndex, schemeLength);
int current = startIndex + schemeLength;
int whitespaceLength = HttpRuleParser.GetWhitespaceLength(input, current);
current = current + whitespaceLength;
if ((current == input.Length) || (input[current] == ','))
{
// If we only have a scheme followed by whitespace, we're done.
parsedValue = result;
return(current - startIndex);
}
// We need at least one space between the scheme and parameters. If there is no whitespace, then we must
// have reached the end of the string (i.e. scheme-only string).
if (whitespaceLength == 0)
{
return(0);
}
// If we get here, we have a <scheme> followed by a whitespace. Now we expect the following:
// '<scheme> <blob>[,<name>=<value>]*[, <otherscheme>...]*': <blob> potentially contains one
// or more '=' characters, optionally followed by additional name/value pairs, optionally followed by
// other schemes. <blob> may be a quoted string.
// We look at the value after ',': if it is <token>=<value> then we have a parameter for <scheme>.
// If we have either a <token>-only or <token><whitespace><blob> then we have another scheme.
int parameterStartIndex = current;
int parameterEndIndex = current;
if (!TrySkipFirstBlob(input, ref current, ref parameterEndIndex))
{
return(0);
}
if (current < input.Length)
{
if (!TryGetParametersEndIndex(input, ref current, ref parameterEndIndex))
{
return(0);
}
}
result._parameter = input.Substring(parameterStartIndex, parameterEndIndex - parameterStartIndex + 1);
parsedValue = result;
return(current - startIndex);
}
internal bool RemoveParsedValue(string name, object value)
{
Contract.Requires((name != null) && (name.Length > 0));
Contract.Requires(HttpRuleParser.GetTokenLength(name, 0) == name.Length);
Contract.Requires(value != null);
if (headerStore == null)
{
return(false);
}
// If we have a value for this header, then verify if we have a single value. If so, compare that
// value with 'item'. If we have a list of values, then remove 'item' from the list.
HeaderStoreItemInfo info = null;
if (TryGetAndParseHeaderInfo(name, out info))
{
Contract.Assert(info.Parser != null, "Can't add parsed value if there is no parser available.");
Contract.Assert(info.Parser.SupportsMultipleValues,
"This method should not be used for single-value headers. Use Remove(string) instead.");
bool result = false;
// If there is no entry, just return.
if (info.ParsedValue == null)
{
return(false);
}
IEqualityComparer comparer = info.Parser.Comparer;
List <object> parsedValues = info.ParsedValue as List <object>;
if (parsedValues == null)
{
Contract.Assert(info.ParsedValue.GetType() == value.GetType(),
"Stored value does not have the same type as 'value'.");
if (AreEqual(value, info.ParsedValue, comparer))
{
info.ParsedValue = null;
result = true;
}
}
else
{
foreach (object item in parsedValues)
{
Contract.Assert(item.GetType() == value.GetType(),
"One of the stored values does not have the same type as 'value'.");
if (AreEqual(value, item, comparer))
{
// Remove 'item' rather than 'value', since the 'comparer' may consider two values
// equal even though the default obj.Equals() may not (e.g. if 'comparer' does
// case-insentive comparison for strings, but string.Equals() is case-sensitive).
result = parsedValues.Remove(item);
break;
}
}
// If we removed the last item in a list, remove the list.
if (parsedValues.Count == 0)
{
info.ParsedValue = null;
}
}
// If there is no value for the header left, remove the header.
if (info.IsEmpty)
{
bool headerRemoved = Remove(name);
Contract.Assert(headerRemoved, "Existing header '" + name + "' couldn't be removed.");
}
return(result);
}
return(false);
}
