[wasm] fix SendAsync_GetWithInvalidHostHeader_ThrowsException - doesn't throw on WASM

[pavelsavara]

System.Net.Http.Functional.Tests.SocketsHttpHandlerTest_HttpClientHandlerTest_Headers_Http11.SendAsync_GetWithInvalidHostHeader_ThrowsException on WASM in browser expects HttpRequestMessage.Headers.Host validation.

Assert.Throws() Failure
Expected: typeof(System.Net.Http.HttpRequestException)\nActual:   (No exception was thrown)]]
   at System.Net.Http.Functional.Tests.HttpClientHandlerTest_Headers.SendAsync_GetWithInvalidHostHeader_ThrowsException()

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Issue Details

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System.Net.Http.Functional.Tests.SocketsHttpHandlerTest_HttpClientHandlerTest_Headers_Http11.SendAsync_GetWithInvalidHostHeader_ThrowsException on WASM in browser expects HttpRequestMessage.Headers.Host validation.

Assert.Throws() Failure
Expected: typeof(System.Net.Http.HttpRequestException)\nActual:   (No exception was thrown)]]
   at System.Net.Http.Functional.Tests.HttpClientHandlerTest_Headers.SendAsync_GetWithInvalidHostHeader_ThrowsException()

Author:	pavelsavara
Assignees:	-
Labels:	arch-wasm, area-System.Net.Http
Milestone:	-

[lewing]

I'm not sure how serious this one is, it looks like we're missing validation on an invalid header and we might end up pulling in a lot of code to do that validation, but someone should take a look.

[ilonatommy]

@pavelsavara, what do you think about @lewing's hypothesis?

[pavelsavara]

Perhaps it's not that bad ?

runtime/src/libraries/System.Net.Http/src/System/Net/Http/Headers/HttpRequestHeaders.cs

Line 116 in 3c33b42

if ((value != null) && (HttpRuleParser.GetHostLength(value, 0, false) != value.Length))

runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpRuleParser.cs

Line 199 in 3c33b42

internal static int GetHostLength(string input, int startIndex, bool allowToken)