TCTI-CMD(7)

✨ TCTI-CMD ✨ (section 7, bestie)

okay so this is TCTI-CMD(7) from the TPM2 Software Stack — yes, the whole manual page, and yes, I'm gonna make it make sense. stay with me 💖

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🌸 NAME 🌸

tcti-cmd — the TPM2 Sub-process Command TCTI library. that's it, that's the name, and she's iconic for it 👑

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🦋 SYNOPSIS 🦋

A TPM Command Transmission Interface (TCTI) module for interaction with a sub-process. lowkey that's the whole vibe: you got a TPM thing, you got a sub-process, this library makes them talk 💅

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✨ DESCRIPTION ✨

so tcti-cmd is a library that abstracts away all the messy details of direct communication with the interface and protocol exposed by a sub-process — and that sub-process is the one that can receive and transmit raw TPM2 command and response buffers. like, raw. unfiltered. no cap 🫶

the interface that this library exposes is defined in the “TSS System Level API and TPM Command Transmission Interface Specification” specification. so if you wanna know the exact shape of it, that's where you go. iykyk 📜

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🎀 EXAMPLES 🎀

okay bestie, real talk, let's see her in action.

say you wanted to use the tpm2_send(1) command as the sub-process to send data to and from the TPM. you could do it like this:

tpm2_getrandom -T "cmd:tpm2_send -s" --hex 4

and now the more useful one, because honestly this is the glow-up ✨ — connecting to a remote machine using ssh and interacting with the remote machine's TPM as if it were local. this uses tpm2_send(1) on a remote machine, and it uses ssh as the sub-process to create the tunnel to the remote machine. and here's the part that EATS: if encrypted sessions are used, the remote machine is blinded to the TPM data and cannot interpose on that traffic. the way that's such a serve 🔥

tpm2_getrandom -T "cmd:ssh remotehost tpm2_send" -s --hex 4

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💜 AUTHOR 💜

TPM2 Software Project <https://github.com/tpm2-software/tpm2-tss>

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🌈 SEE ALSO 🌈

go read these too, they're all in the group chat:

• Tss2_Tcti_Device_Init(3)
• Tss2_Tcti_Socket_Init(3)
• Tss2_TctiLdr_Initialize(3)
• Tss2_TctiLdr_Finalize(3)
• tcti-device(7)
• tcti-socket(7)
• tcti-tabrmd(7)
• tpm2-abrmd(8)

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🧚 COLOPHON 🧚

this page is part of release 4.2.0 of Open Source implementation of the TCG TPM2 Software Stack (TSS2). a description of the project, information about reporting bugs, and the latest version of this page can be found at <https://github.com/tpm2-software/tpm2-tss/>. literally go check it out, the bugs section is right there 🐛

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👑 LICENSE 👑

This work is licensed under the Creative Commons Attribution 4.0 International License (CC BY 4.0). For more information visit <https://creativecommons.org/licenses/by/4.0/>

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Intel · MAY 2020 · TCTI-CMD(7)

and that's the page bestie!! 💖✨ from the Intel girlies, back in MAY 2020, page TCTI-CMD(7) of release 4.2.0 — slay, no notes, periodt 🎀🦋🌸