[enhancement]: Mitigate homograph attacks from human-interpreted strings

[dstadulis]

Background

As a taproot-assets user I want to only need to visually inspect an asset name in order to confirm that a bootstrapped asset has the name I believe it should have

As a taproot-assets asset issuer I want to ensure that my asset name cannot be confused with visually indistinguishable asset names in order to preserve my asset's name recognition and deny fraud

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Given that many unicode glyphs appear visually indistinguishable from each other but map to different code points, there is a potential attack vector against humans visually comparing asset names in which an attacker could attempt to defraud a user by using two homoglyphs. Domain names call this the IDN homograph attack

Mitigation options

• Enforce ASCII-only names. Upside: simple Downside: Excludes non-English language asset names
• Use Punycode or equivalent to excluding homographs and enforce those in tapd
• Allow Homographs but add a visual fingerprint (for the homograph attackable fields) for users to easily detect naming mismatches

Strings sensitive homograph attacks:

• Asset names
• Universe servers
• TODO: enumerate more areas

[Crypt-iQ]

Using only an asset's name is fragile imo because it's hard to tell the difference between some ascii characters like l and I or l and 1. Isn't there an asset hash that people can use instead?

[jharveyb]

Some notes on normalization that help avoid some cases of this:

https://go.dev/blog/normalization

Using only an asset's name is fragile imo because it's hard to tell the difference between some ascii characters like l and I or l and 1. Isn't there an asset hash that people can use instead?

Yes, the asset ID would be unique even across visually-similar asset tags. I think option 3 / convert asset ID to visual fingerprint seems best.

You could maybe have a universe reject visually-similar asset tags but that doesn't sound robust tbh / adds a form of squatting.

[Crypt-iQ]

Another string that might be sensitive (adding to the list) is the proof courier address