strongSwan

h1. Trusted Platform Module 2.0

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h2. Connect to a TPM 2.0 device

In order to connect to a TPM 2.0 hardware or firmware device, the TSS2 software stack developed by Intel is needed. Because the official Ubuntu *tpm2-tss* package is rather outdated (e.g. since version 0.98 the TCTI interface to the TPM 2.0 resource manager has changed several times), strongSwan is currently based on a recent version directly drawn from the TPM2-TSS git repository https://github.com/01org/TPM2.0-TSS. Avoid any TCTI interface incompatibilities by fetching the latest *tpm2-tools* version from https://github.com/01org/tpm2.0-tools as well.

Build and install both the *tpm2-tss* stack and the *tpm2.0-tools*, start the *tpm2-resourcemgr* as a servicein the background and try to connect to the TPM 2.0 by listing e.g. the contents of the SHA-1 bank of PCR registers


tpm2_listpcrs -g 0x0004

Bank/Algorithm: TPM_ALG_SHA1(0x0004)
PCR_00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PCR_01: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PCR_02: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PCR_03: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PCR_04: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PCR_05: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PCR_06: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PCR_07: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PCR_08: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PCR_09: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PCR_10: a9 45 e7 0f 42 a2 79 f0 78 ca d4 64 60 39 39 da 9d 6a d1 a5
PCR_11: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PCR_12: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PCR_13: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PCR_14: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PCR_15: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PCR_16: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PCR_17: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
PCR_18: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
PCR_19: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
PCR_20: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
PCR_21: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
PCR_22: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
PCR_23: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

A manual showing all *tpm2-tools* functions with their arguments can be found "here":https://github.com/01org/tpm2.0-tools/blob/master/manual.

h2. TPM 2.0 Algorithm IDs

h3. Hash Algorithms


|0x0004 |SHA-1 |
|0x000B |SHA-2_256 |
|0x000C |SHA-2_384 |
|0x000D |SHA-2_512 |

Currently available TPM 2.0 devices like the Infineon *Optiga SLB 9670 VQ2.0* hardware TPM or Intel's *PTT* firmware TPM support the *SHA-1* SHA-1 and *SHA-2_256* SHA-2_256 algorithms.

h3. Public Key Types

|0x0001 |RSA |
|0x0023 |ECC |

The RSA keys have a modulus size of 2048 bits and the ECC keys are based on the 256 bit NIST curve.
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h2. TPM Private Key Access via VICI Interface

Configuration of TPM private key access in *swanctl.conf*:

secrets {
token_ak_rsa {
handle = 81010002
}
token_ak_ecc {
handle = 81010004
}
}