why it is wrong ?

I want to compute SHA1(salt | SHA1(identity | ":" | pass))
cli.hasher = hash.sha1;
var h = cli.hasher();
var buf1 = h.update(cli.identity + ':' + cli.pass).digest('hex');
// console.log("XXX", buf1)

var h2 = cli.hasher();
var buf2 = h2.update(cli.salt).digest('hex');
console.log("buf2", buf2)

var h3 = cli.hasher();
var buf3 = h3.update(buf1).update(buf2).digest('hex');
console.log("buf3", buf3)

Start by reproducing the calculation using the hash.sha1 entry point and the cli.hasher calls shown in the issue. Compare the resulting values with the expected SHA1(salt | SHA1(identity | ":" | pass)) output, including how each intermediate value is represented. Done means the discrepancy is explained and the issue's expected computation is verified or corrected.

Written by the indexing model from the issue text.