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Subject: [Bitcoin-development] Payment Protocol Hash Comments
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 From BIP70:

   If pki_type is "x509+sha256", then the Payment message is hashed using  
the
   SHA256 algorithm to produce the message digest that is signed. If  
pki_type
   is "x509+sha1", then the SHA1 algorithm is used.

A couple minor comments;

  - I think it meant to say the field to be hashed is 'PaymentRequest' not  
'Payment' message -- probably got renamed at some point and this is an old  
reference calling it by its original name.

  - Could be a bit more explicit about the hashing, e.g. 'copy the  
PaymentRequest, set the signature field to the empty string, serialize to  
a byte[] and hash.

  - SHA1 is retiring, any particular reason to even have it in there at all?

  - Should there any way for the end-user to see details like the pki_type  
and the certificate chain, like browser do?


Thanks,
Jeremy