Workaround unprivileged PacketConn on darwin returns the entire IP packet in icmp.ListenPacket() #37
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…cket in icmp.ListenPacket() Signed-off-by: Jeremiah Millay <jmillay@fastly.com>
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TLDR: unprivileged icmp echo replies are discarded on macOS (darwin)
This is a patch to work around an issue described in golang/go#47369 which can be summarized as follows:
Due to setting the IP_STRPHDR socket option in darwin (macOS) environments,
reads on unprivileged sockets (udp) include the IP header before the ICMP header in the read bytes returned by
icmp.ListenPacket(). As a result of this,pro-bingends up discarding icmp echo replies due to the unexpected ip header bytes returned byicmp.ListenPacket().While this problem needs to be addressed in go itself, this patch provides a work around until this issue is addressed.