[PATCH v2 0/6] KEYS: asymmetric: tpm2_key_rsa

Jarkko Sakkinen
2024-05-21T03:16:50Z

## Overview

Introduce tpm2_key_rsa module, which implements asymmetric TPM2 RSA key.
The feature can be enabled with the CONFIG_ASYMMETRIC_TPM2_KEY_RSA_SUBTYPE
kconfig option.

The idea in the design is to over time to have submodule per key type
For instance, tpm2_key_ecdsa could be one potential future addition in
the future. Perhaps, it might sense to consider at that point also a
top-level tpm2_key module. The gist is that the naming convention is
free from potential future bottlencks.

## Change Log

v2
Cleaned up all the low-hanging fruit for the sake of saving everyones
time. After this I move into reactive mode (I promise) ;-)

## Testing

tpm2_createprimary --hierarchy o -G rsa2048 -c owner.txt
tpm2_evictcontrol -c owner.txt 0x81000001
tpm2_getcap handles-persistent
openssl genrsa -out private.pem 2048
tpm2_import -C 0x81000001 -G rsa -i private.pem -u key.pub -r key.priv
tpm2_encodeobject -C 0x81000001 -u key.pub -r key.priv -o key.priv.pem
openssl asn1parse -inform pem -in key.priv.pem -noout -out key.priv.der
serial=`cat key.priv.der | keyctl padd asymmetric tpm @u`
echo "abcdefg" > plaintext.txt
keyctl pkey_encrypt $serial 0 plaintext.txt enc=pkcs1 > encrypted.dat
keyctl pkey_decrypt $serial 0 encrypted.dat enc=pkcs1 > decrypted.dat
keyctl pkey_sign $serial 0 plaintext.txt enc=pkcs1 hash=sha256 > signed.dat
keyctl pkey_verify $serial 0 plaintext.txt signed.dat enc=pkcs1 hash=sha256

## References

- v1: https://lore.kernel.org/linux-integrity/20240520184727.22038-1-jarkko@kernel.org/
- Derived from https://lore.kernel.org/all/20200518172704.29608-1-prestwoj@gmail.com/

James Prestwood (1):
keys: asymmetric: ASYMMETRIC_TPM2_KEY_RSA_SUBTYPE

Jarkko Sakkinen (5):
crypto: rsa-pkcs1pad: export rsa1_asn_lookup()
lib: Expand asn1_encode_integer() to variable size integers
tpm: Export tpm2_load_context()
KEYS: trusted: Move tpm2_key_decode() to the TPM driver
tpm: tpm2_key: Extend parser to TPM_LoadableKey

crypto/asymmetric_keys/Kconfig | 16 +
crypto/asymmetric_keys/Makefile | 1 +
crypto/asymmetric_keys/tpm2_key_rsa.c | 698 ++++++++++++++++++
crypto/rsa-pkcs1pad.c | 16 +-
drivers/char/tpm/Kconfig | 1 +
drivers/char/tpm/Makefile | 5 +
drivers/char/tpm/tpm.h | 2 -
drivers/char/tpm/tpm2-cmd.c | 77 ++
drivers/char/tpm/tpm2-space.c | 61 --
drivers/char/tpm/tpm2_key.c | 119 +++
.../char/tpm}/tpm2key.asn1 | 0
include/crypto/rsa-pkcs1pad.h | 20 +
include/crypto/tpm2_key.h | 35 +
include/linux/asn1_encoder.h | 3 +-
include/linux/tpm.h | 4 +
lib/asn1_encoder.c | 185 ++---
security/keys/trusted-keys/Makefile | 2 -
security/keys/trusted-keys/trusted_tpm2.c | 135 +---
18 files changed, 1110 insertions(+), 270 deletions(-)
create mode 100644 crypto/asymmetric_keys/tpm2_key_rsa.c
create mode 100644 drivers/char/tpm/tpm2_key.c
rename {security/keys/trusted-keys => drivers/char/tpm}/tpm2key.asn1 (100%)
create mode 100644 include/crypto/rsa-pkcs1pad.h
create mode 100644 include/crypto/tpm2_key.h

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2.45.1