Fix parsing of ping error replies on raw sockets

[filipnavara]

Fixes #61465

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Issue Details

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Fixes #61465

Needs more testing. The ICMPv4 code path was tested locally, ICMPv6 was not tested at all.

Author:	filipnavara
Assignees:	-
Labels:	area-System.Net, community-contribution
Milestone:	-

[wfurt]

LGTM

ifconfig en0
en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
	options=10b<RXCSUM,TXCSUM,VLAN_HWTAGGING,AV>
	ether 68:5b:35:ce:4a:d8
	inet6 fe80::1c62:813b:8b0d:4b5%en0 prefixlen 64 secured scopeid 0x7
	inet 10.127.72.87 netmask 0xfffffc00 broadcast 10.127.75.255
	inet6 2001:4898:f0:20:1c02:4dba:a6b5:e6c0 prefixlen 64 autoconf secured

$  /Users/presenter/Downloads/ping/bin/Debug/net6.0/osx-x64/publish/ping
Status: TimeExceeded Address: 2001:4898:f0:20:ff::2

it would be great IMHO to add (outerloop) test. It would need to ignore cases when there is no answer and perhaps simply test that the address is not ANY.
I would add two entries (for v4 & v6) similar to

runtime/src/libraries/Common/tests/System/Net/Configuration.Ping.cs

Line 11 in a1b391b

public static string PingHost => GetValue("DOTNET_TEST_NET_PING_HOST", "www.microsoft.com");

with 8.8.8.8 and 2001:4860:4860::8888 as defaults.

[filipnavara]

Thanks for testing it. Apparently there's already similar test (SendPingToExternalHostWithLowTtlTest) in outer loop, it just doesn't validate ICMPv6 and the resulting Status/Address.

[wfurt]

LGTM.
thanks @filipnavara