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I am able to do either of the following:

Host match using standard operators:

if (req.http.Host == "" || req.http.Host == "") { ... }

Host match via regex:

if (req.http.Host ~ "^(|$") { ... }

My question is, is option #2 bad performance-wise or security-wise? I understand that omitting the start and end regex characters could allow someone to put a domain like potentially, but with ^ and $ that doesn't seem possible.

Any other thoughts/ideas as to how to approach this would be appreciated.

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1 Answer 1

Well, I don't really think that there are any performance implications of using any of the above approaches, but I usually like to stay with the regular expression as it gives me power as well as flexibility, to match a lot of things.

Regarding the security, what you said is absolutely right and using the first option can be abused.

If I would have been working on something like this, I will surely prefer the second approach.

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