[v3,0/5] KEYS: asymmetric: tpm2_key_rsa

## 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

v3:
* Dropped special policy when RH_NULL is given. Kernel will just try to
  use the handle as parent given.
* Thus could drop the patch exporting tpm2_load_context().
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

- v2: https://lore.kernel.org/linux-integrity/20240521031645.17008-1-jarkko@kernel.org/
- 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 (4):
  crypto: rsa-pkcs1pad: export rsa1_asn_lookup()
  lib: Expand asn1_encode_integer() to variable size integers
  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         | 688 ++++++++++++++++++
 crypto/rsa-pkcs1pad.c                         |  16 +-
 drivers/char/tpm/Kconfig                      |   1 +
 drivers/char/tpm/Makefile                     |   5 +
 drivers/char/tpm/tpm2_key.c                   | 118 +++
 .../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                           |   2 +
 lib/asn1_encoder.c                            | 185 ++---
 security/keys/trusted-keys/Makefile           |   2 -
 security/keys/trusted-keys/trusted_tpm2.c     | 135 +---
 15 files changed, 1020 insertions(+), 207 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