aspnetcore/src/Microsoft.AspNetCore.Http.A.../HostString.cs

385 lines
13 KiB
C#

// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
using System;
using System.Collections.Generic;
using System.Globalization;
using Microsoft.AspNetCore.Http.Abstractions;
using Microsoft.AspNetCore.Http.Internal;
using Microsoft.Extensions.Primitives;
namespace Microsoft.AspNetCore.Http
{
/// <summary>
/// Represents the host portion of a URI can be used to construct URI's properly formatted and encoded for use in
/// HTTP headers.
/// </summary>
public struct HostString : IEquatable<HostString>
{
private readonly string _value;
/// <summary>
/// Creates a new HostString without modification. The value should be Unicode rather than punycode, and may have a port.
/// IPv4 and IPv6 addresses are also allowed, and also may have ports.
/// </summary>
/// <param name="value"></param>
public HostString(string value)
{
_value = value;
}
/// <summary>
/// Creates a new HostString from its host and port parts.
/// </summary>
/// <param name="host">The value should be Unicode rather than punycode. IPv6 addresses must use square braces.</param>
/// <param name="port">A positive, greater than 0 value representing the port in the host string.</param>
public HostString(string host, int port)
{
if (host == null)
{
throw new ArgumentNullException(nameof(host));
}
if (port <= 0)
{
throw new ArgumentOutOfRangeException(nameof(port), Resources.Exception_PortMustBeGreaterThanZero);
}
int index;
if (host.IndexOf('[') == -1
&& (index = host.IndexOf(':')) >= 0
&& index < host.Length - 1
&& host.IndexOf(':', index + 1) >= 0)
{
// IPv6 without brackets ::1 is the only type of host with 2 or more colons
host = $"[{host}]";
}
_value = host + ":" + port.ToString(CultureInfo.InvariantCulture);
}
/// <summary>
/// Returns the original value from the constructor.
/// </summary>
public string Value
{
get { return _value; }
}
public bool HasValue
{
get { return !string.IsNullOrEmpty(_value); }
}
/// <summary>
/// Returns the value of the host part of the value. The port is removed if it was present.
/// IPv6 addresses will have brackets added if they are missing.
/// </summary>
/// <returns></returns>
public string Host
{
get
{
GetParts(_value, out var host, out var port);
return host.ToString();
}
}
/// <summary>
/// Returns the value of the port part of the host, or <value>null</value> if none is found.
/// </summary>
/// <returns></returns>
public int? Port
{
get
{
GetParts(_value, out var host, out var port);
if (!StringSegment.IsNullOrEmpty(port)
&& int.TryParse(port.ToString(), NumberStyles.None, CultureInfo.InvariantCulture, out var p))
{
return p;
}
return null;
}
}
/// <summary>
/// Returns the value as normalized by ToUriComponent().
/// </summary>
/// <returns></returns>
public override string ToString()
{
return ToUriComponent();
}
/// <summary>
/// Returns the value properly formatted and encoded for use in a URI in a HTTP header.
/// Any Unicode is converted to punycode. IPv6 addresses will have brackets added if they are missing.
/// </summary>
/// <returns></returns>
public string ToUriComponent()
{
if (string.IsNullOrEmpty(_value))
{
return string.Empty;
}
int i;
for (i = 0; i < _value.Length; ++i)
{
if (!HostStringHelper.IsSafeHostStringChar(_value[i]))
{
break;
}
}
if (i != _value.Length)
{
GetParts(_value, out var host, out var port);
var mapping = new IdnMapping();
var encoded = mapping.GetAscii(host.Buffer, host.Offset, host.Length);
return StringSegment.IsNullOrEmpty(port)
? encoded
: string.Concat(encoded, ":", port.ToString());
}
return _value;
}
/// <summary>
/// Creates a new HostString from the given URI component.
/// Any punycode will be converted to Unicode.
/// </summary>
/// <param name="uriComponent"></param>
/// <returns></returns>
public static HostString FromUriComponent(string uriComponent)
{
if (!string.IsNullOrEmpty(uriComponent))
{
int index;
if (uriComponent.IndexOf('[') >= 0)
{
// IPv6 in brackets [::1], maybe with port
}
else if ((index = uriComponent.IndexOf(':')) >= 0
&& index < uriComponent.Length - 1
&& uriComponent.IndexOf(':', index + 1) >= 0)
{
// IPv6 without brackets ::1 is the only type of host with 2 or more colons
}
else if (uriComponent.IndexOf("xn--", StringComparison.Ordinal) >= 0)
{
// Contains punycode
if (index >= 0)
{
// Has a port
string port = uriComponent.Substring(index);
var mapping = new IdnMapping();
uriComponent = mapping.GetUnicode(uriComponent, 0, index) + port;
}
else
{
var mapping = new IdnMapping();
uriComponent = mapping.GetUnicode(uriComponent);
}
}
}
return new HostString(uriComponent);
}
/// <summary>
/// Creates a new HostString from the host and port of the give Uri instance.
/// Punycode will be converted to Unicode.
/// </summary>
/// <param name="uri"></param>
/// <returns></returns>
public static HostString FromUriComponent(Uri uri)
{
if (uri == null)
{
throw new ArgumentNullException(nameof(uri));
}
return new HostString(uri.GetComponents(
UriComponents.NormalizedHost | // Always convert punycode to Unicode.
UriComponents.HostAndPort, UriFormat.Unescaped));
}
/// <summary>
/// Matches the host portion of a host header value against a list of patterns.
/// The host may be the encoded punycode or decoded unicode form so long as the pattern
/// uses the same format.
/// </summary>
/// <param name="value">Host header value with or without a port.</param>
/// <param name="patterns">A set of pattern to match, without ports.</param>
/// <remarks>
/// The port on the given value is ignored. The patterns should not have ports.
/// The patterns may be exact matches like "example.com", a top level wildcard "*"
/// that matches all hosts, or a subdomain wildcard like "*.example.com" that matches
/// "abc.example.com:443" but not "example.com:443".
/// Matching is case insensitive.
/// </remarks>
/// <returns></returns>
public static bool MatchesAny(StringSegment value, IList<StringSegment> patterns)
{
if (value == null)
{
throw new ArgumentNullException(nameof(value));
}
if (patterns == null)
{
throw new ArgumentNullException(nameof(patterns));
}
// Drop the port
GetParts(value, out var host, out var port);
for (int i = 0; i < port.Length; i++)
{
if (port[i] < '0' || '9' < port[i])
{
throw new FormatException($"The given host value '{value}' has a malformed port.");
}
}
for (int i = 0; i < patterns.Count; i++)
{
var pattern = patterns[i];
if (pattern == "*")
{
return true;
}
if (StringSegment.Equals(pattern, host, StringComparison.OrdinalIgnoreCase))
{
return true;
}
// Sub-domain wildcards: *.example.com
if (pattern.StartsWith("*.", StringComparison.Ordinal) && host.Length >= pattern.Length)
{
// .example.com
var allowedRoot = pattern.Subsegment(1);
var hostRoot = host.Subsegment(host.Length - allowedRoot.Length);
if (hostRoot.Equals(allowedRoot, StringComparison.OrdinalIgnoreCase))
{
return true;
}
}
}
return false;
}
/// <summary>
/// Compares the equality of the Value property, ignoring case.
/// </summary>
/// <param name="other"></param>
/// <returns></returns>
public bool Equals(HostString other)
{
if (!HasValue && !other.HasValue)
{
return true;
}
return string.Equals(_value, other._value, StringComparison.OrdinalIgnoreCase);
}
/// <summary>
/// Compares against the given object only if it is a HostString.
/// </summary>
/// <param name="obj"></param>
/// <returns></returns>
public override bool Equals(object obj)
{
if (ReferenceEquals(null, obj))
{
return !HasValue;
}
return obj is HostString && Equals((HostString)obj);
}
/// <summary>
/// Gets a hash code for the value.
/// </summary>
/// <returns></returns>
public override int GetHashCode()
{
return (HasValue ? StringComparer.OrdinalIgnoreCase.GetHashCode(_value) : 0);
}
/// <summary>
/// Compares the two instances for equality.
/// </summary>
/// <param name="left"></param>
/// <param name="right"></param>
/// <returns></returns>
public static bool operator ==(HostString left, HostString right)
{
return left.Equals(right);
}
/// <summary>
/// Compares the two instances for inequality.
/// </summary>
/// <param name="left"></param>
/// <param name="right"></param>
/// <returns></returns>
public static bool operator !=(HostString left, HostString right)
{
return !left.Equals(right);
}
/// <summary>
/// Parses the current value. IPv6 addresses will have brackets added if they are missing.
/// </summary>
private static void GetParts(StringSegment value, out StringSegment host, out StringSegment port)
{
int index;
port = null;
host = null;
if (StringSegment.IsNullOrEmpty(value))
{
return;
}
else if ((index = value.IndexOf(']')) >= 0)
{
// IPv6 in brackets [::1], maybe with port
host = value.Subsegment(0, index + 1);
// Is there a colon and at least one character?
if (index + 2 < value.Length && value[index + 1] == ':')
{
port = value.Subsegment(index + 2);
}
}
else if ((index = value.IndexOf(':')) >= 0
&& index < value.Length - 1
&& value.IndexOf(':', index + 1) >= 0)
{
// IPv6 without brackets ::1 is the only type of host with 2 or more colons
host = $"[{value}]";
port = null;
}
else if (index >= 0)
{
// Has a port
host = value.Subsegment(0, index);
port = value.Subsegment(index + 1);
}
else
{
host = value;
port = null;
}
}
}
}