Is there a standard function signature for the digital signature "verify" function?

Question

Is one of these (or something else) more standard than the alternatives?

verify(message, signature, publicKey)

vs

verify(signature, message, publicKey)

Answer 1

I would go for:

verify(publicKey, message, signature)

and there is objective reasoning behind it. Normally you first have to provide the public key (e.g. in an init method in the case of Java, then the data itself (e.g. in an update method) and finally you verify the actual signature. Note that the publicKey is often static; I personally prefer those at the start of the method.

Likewise, the signature generation would be:

sign(privateKey, message): signature

as you can see, nicely symmetric.

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And since you are asking for a standard:

RSASSA-PSS-VERIFY ((n, e), M, S)

where (n, e) is the public key. This is straight out of RFC 3447 describing the RSA Cryptography Specifications.