Using the HASH function

[XeAtari]

From my understanding it would be necessary to tell the FujiNet in advance the amount of buffer it has to reserve for the data that it will be sent.

Beyond this I guess some kind of init will be necessary that tells FujiNet that a new procedure is going to start.

There are 4 SIO commands ($C5 to $C8) to go through this procedure ($C6 still needs documentation)

So the commands have to be sent in some order:

1. ?
2. Upload file (in multiple blocks if needed) ($C8 Hash Input)
3. Calculate hash ($C7 Hash Compute)
4. Get Result ($C5 Hash Output)

So the command that obviously needs to be sent first is $C6 (Hash Length)

So it logically follows that $C6 has to tell the FujiNet that a new procedure starts, reset buffer pointers (those pointers that keep track of the data blocks) and what amount of data it is going to receive in total.

I assume that $C6 will have to be used like $CE, sending 4 bytes to the FujiNet telling about the length of the file to come (which is 4 GB minus some 66 MB).

Du I understand this correct?

[tschak909]

The hash functions provide a single hash output for anything put into input, and you can keep feeding into input as RAM will be allocated to provide the buffer dynamically. The buffer used by FujiNet for hash calculation is dynamically allocated from PSRAM (there is 4 megabytes of it) and is represented internally as a std::string. So if you want to use these functions directly, use them in this order: 1. https://github.com/FujiNetWIFI/fujinet-firmware/wiki/SIO-Command-$C8-Hash-Input (as much as needed) 2. https://github.com/FujiNetWIFI/fujinet-firmware/wiki/SIO-Command-$C7-Hash-Compute (to compute the hash) 3. hash length (it works similar to the other base64/etc functions near it. and is needed so you know how many bytes to fetch.) (sorry the documentation will be amended) 4. https://github.com/FujiNetWIFI/fujinet-firmware/wiki/SIO-Command-$C5-Hash-Output So by the time you get to step 4, you'll have e.g. for md5 a 32 byte ascii hex string.

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-Thom

On Tue, Nov 18, 2025 at 2:38 AM XeAtari ***@***.***> wrote: *XeAtari* created an issue (FujiNetWIFI/fujinet-firmware#1074) <#1074> From my understanding it would be necessary to tell the FujiNet in advance the amount of buffer it has to reserve for the data that it will be sent. Beyond this I guess some kind of init will be necessary that tells FujiNet that a new procedure is going to start. There are 4 SIO commands ($C5 to $C8) to go through this procedure ($C6 still needs documentation) So the commands have to be sent in some order: 1. ? 2. Upload file (in multiple blocks if needed) ($C8 Hash Input) 3. Calculate hash ($C7 Hash Compute) 4. Get Result ($C5 Hash Output) So the command that obviously needs to be sent first is $C6 (Hash Length) So it logically follows that $C6 has to tell the FujiNet that a new procedure starts, reset buffer pointers (those pointers that keep track of the data blocks) and what amount of data it is going to receive in total. I assume that $C6 will have to be used like $CE, sending 4 bytes to the FujiNet telling about the length of the file to come (which is 4 GB minus some 66 MB). Du I understand this correct? — Reply to this email directly, view it on GitHub <#1074>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAVBYZVMKVBZZIJUVOCANF335LLJ3AVCNFSM6AAAAACMNVMWJKVHI2DSMVQWIX3LMV43ASLTON2WKOZTGYZTMOBTGE3DENI> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[FozzTexx]

I have a hash function test as part of the standard integration testing and I've never been able to make it work.

[XeAtari]

@tschak909

Thank you very much for that explanation.

I'll give things a try at the weekend.