Skip to content

Use ordinal comparison for known header values #64702

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
MihaZupan merged 2 commits into from
Feb 3, 2022
Merged

Use ordinal comparison for known header values #64702

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
577b6e2
Use ordinal comparison for known header values
MihaZupan Feb 2, 2022
e8f4850
Match 'text/html; charset=UTF-8' again
MihaZupan Feb 2, 2022
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
47 changes: 24 additions & 23 deletions src/libraries/System.Net.Http/src/System/Net/Http/Headers/HeaderDescriptor.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -132,7 +132,7 @@ public string GetHeaderValue(ReadOnlySpan<byte> headerValue, Encoding? valueEnco
{
for (int i = 0; i < knownValues.Length; i++)
{
if (ByteArrayHelpers.EqualsOrdinalAsciiIgnoreCase(knownValues[i], headerValue))
if (ByteArrayHelpers.EqualsOrdinalAscii(knownValues[i], headerValue))
{
return knownValues[i];
}
Expand Down Expand Up @@ -166,45 +166,45 @@ public string GetHeaderValue(ReadOnlySpan<byte> headerValue, Encoding? valueEnco
switch (contentTypeValue.Length)
{
case 8:
switch (contentTypeValue[7] | 0x20)
switch (contentTypeValue[7])
{
case 'l': candidate = "text/xml"; break; // text/xm[l]
case 's': candidate = "text/css"; break; // text/cs[s]
case 'v': candidate = "text/csv"; break; // text/cs[v]
case (byte)'l': candidate = "text/xml"; break; // text/xm[l]
case (byte)'s': candidate = "text/css"; break; // text/cs[s]
case (byte)'v': candidate = "text/csv"; break; // text/cs[v]
}
break;

case 9:
switch (contentTypeValue[6] | 0x20)
switch (contentTypeValue[6])
{
case 'g': candidate = "image/gif"; break; // image/[g]if
case 'p': candidate = "image/png"; break; // image/[p]ng
case 't': candidate = "text/html"; break; // text/h[t]ml
case (byte)'g': candidate = "image/gif"; break; // image/[g]if
case (byte)'p': candidate = "image/png"; break; // image/[p]ng
case (byte)'t': candidate = "text/html"; break; // text/h[t]ml
}
break;

case 10:
switch (contentTypeValue[0] | 0x20)
switch (contentTypeValue[0])
{
case 't': candidate = "text/plain"; break; // [t]ext/plain
case 'i': candidate = "image/jpeg"; break; // [i]mage/jpeg
case (byte)'t': candidate = "text/plain"; break; // [t]ext/plain
case (byte)'i': candidate = "image/jpeg"; break; // [i]mage/jpeg
}
break;

case 15:
switch (contentTypeValue[12] | 0x20)
switch (contentTypeValue[12])
{
case 'p': candidate = "application/pdf"; break; // application/[p]df
case 'x': candidate = "application/xml"; break; // application/[x]ml
case 'z': candidate = "application/zip"; break; // application/[z]ip
case (byte)'p': candidate = "application/pdf"; break; // application/[p]df
case (byte)'x': candidate = "application/xml"; break; // application/[x]ml
case (byte)'z': candidate = "application/zip"; break; // application/[z]ip
}
break;

case 16:
switch (contentTypeValue[12] | 0x20)
switch (contentTypeValue[12])
{
case 'g': candidate = "application/grpc"; break; // application/[g]rpc
case 'j': candidate = "application/json"; break; // application/[j]son
case (byte)'g': candidate = "application/grpc"; break; // application/[g]rpc
case (byte)'j': candidate = "application/json"; break; // application/[j]son
}
break;

Expand All @@ -217,10 +217,11 @@ public string GetHeaderValue(ReadOnlySpan<byte> headerValue, Encoding? valueEnco
break;

case 24:
switch (contentTypeValue[0] | 0x20)
switch (contentTypeValue[19])
{
case 'a': candidate = "application/octet-stream"; break; // application/octet-stream
case 't': candidate = "text/html; charset=utf-8"; break; // text/html; charset=utf-8
case (byte)'t': candidate = "application/octet-stream"; break; // application/octet-s[t]ream
case (byte)'u': candidate = "text/html; charset=utf-8"; break; // text/html; charset=[u]tf-8
case (byte)'U': candidate = "text/html; charset=UTF-8"; break; // text/html; charset=[U]TF-8
}
break;

Expand All @@ -239,7 +240,7 @@ public string GetHeaderValue(ReadOnlySpan<byte> headerValue, Encoding? valueEnco

Debug.Assert(candidate is null || candidate.Length == contentTypeValue.Length);

return candidate != null && ByteArrayHelpers.EqualsOrdinalAsciiIgnoreCase(candidate, contentTypeValue) ?
return candidate != null && ByteArrayHelpers.EqualsOrdinalAscii(candidate, contentTypeValue) ?
candidate :
null;
}
Expand Down
38 changes: 29 additions & 9 deletions src/libraries/System.Net.Http/tests/UnitTests/Headers/KnownHeadersTest.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -177,6 +177,7 @@ public void TryGetKnownHeader_Unknown_NotFound(string name)
[InlineData("Content-Type", "application/javascript")]
[InlineData("Content-Type", "application/octet-stream")]
[InlineData("Content-Type", "text/html; charset=utf-8")]
[InlineData("Content-Type", "text/html; charset=UTF-8")]
[InlineData("Content-Type", "text/plain; charset=utf-8")]
[InlineData("Content-Type", "application/json; charset=utf-8")]
[InlineData("Content-Type", "application/x-www-form-urlencoded")]
Expand Down Expand Up @@ -213,27 +214,46 @@ public void TryGetKnownHeader_Unknown_NotFound(string name)
[InlineData("X-XSS-Protection", "1; mode=block")]
public void GetKnownHeaderValue_Known_Found(string name, string value)
{
foreach (string casedValue in new[] { value, value.ToUpperInvariant(), value.ToLowerInvariant() })
KnownHeader knownHeader = KnownHeaders.TryGetKnownHeader(name);
Assert.NotNull(knownHeader);

string v1 = knownHeader.Descriptor.GetHeaderValue(value.Select(c => (byte)c).ToArray(), valueEncoding: null);
Assert.NotNull(v1);
Assert.Equal(value, v1);

string v2 = knownHeader.Descriptor.GetHeaderValue(value.Select(c => (byte)c).ToArray(), valueEncoding: null);
Assert.Same(v1, v2);

if (TryChangeCasing(value, out string newValue)) // Doesn't make sense for values that are just numbers
{
Validate(KnownHeaders.TryGetKnownHeader(name), casedValue);
GetKnownHeaderValue_Unknown_NotFound(name, newValue);
}

static void Validate(KnownHeader knownHeader, string value)
static bool TryChangeCasing(string value, out string newValue)
{
Assert.NotNull(knownHeader);
string upper = value.ToUpperInvariant();
if (upper != value)
{
newValue = upper;
return true;
}

string v1 = knownHeader.Descriptor.GetHeaderValue(value.Select(c => (byte)c).ToArray(), valueEncoding: null);
Assert.NotNull(v1);
Assert.Equal(value, v1, StringComparer.OrdinalIgnoreCase);
string lower = value.ToLowerInvariant();
if (lower != value)
{
newValue = lower;
return true;
}

string v2 = knownHeader.Descriptor.GetHeaderValue(value.Select(c => (byte)c).ToArray(), valueEncoding: null);
Assert.Same(v1, v2);
newValue = null;
return false;
}
}

[Theory]
[InlineData("Content-Type", "application/jsot")]
[InlineData("Content-Type", "application/jsons")]
[InlineData("Transfer-Encoding", "foo")]
public void GetKnownHeaderValue_Unknown_NotFound(string name, string value)
{
KnownHeader knownHeader = KnownHeaders.TryGetKnownHeader(name);
Expand Down