Add option to compute http BodySHA256 on decoded BodyText

[twschum]

Adds a new way to compute the BodyHash for http scanner.

How to Test

echo <ip> | ./zgrab2 http --port 443 --compute-decoded-body-hash-algorithm=sha256 | jq
 "body_hash": "sha256:ff990fc95970bd2fc6333663ae043aaef308117190507bbd7b4831244cd97c2d",

echo <ip> | ./zgrab2 http --port 443 --compute-decoded-body-hash-algorithm=sha1 | jq
"body_hash": "sha1:a829c753bb3e30296c1faeea6783edf7dd23824f",

./zgrab2 http --port 443 --compute-decoded-body-hash-algorithm=md5 | jq
Invalid value `md5' for option `--compute-decoded-body-hash-algorithm'. Allowed values are: sha256 or sha1

Notes & Caveats

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Issue Tracking

Add a link to the relevant GitHub issue(s) if the pull request resolves it.

[codyprime]

If we are adding some new options to compute hash, can we also add an option for SHA1 as well? E.g., a config option like BodyHashAlgorithm that can be "sha1" or "sha256", and a corresponding new field in the Response for just Hash instead of BodySHA256. If the new flag is used populate Hash with the specified algorithm, otherwise it behaves as it currently does now. Also, can the Hash field then have a the algorithm prefix (e.g. ."sha1:")

[p-l-]

Quick question: would it be possible to have the possibility to select one or more hash functions, so that we could have MD5, SHA1 and SHA256 computed and reported? You never know which hash function are used by other applications.

[codyprime]

Quick question: would it be possible to have the possibility to select one or more hash functions, so that we could have MD5, SHA1 and SHA256 computed and reported? You never know which hash function are used by other applications.

I do think that would be nice to have, I guess now as a future enhancement to this patch.