[PATCH v12 00/10] Add support for x509 certs with NIST P384/256/192 keys

Stefan Berger stefanb at linux.ibm.com
Tue Mar 16 21:07:30 UTC 2021

This series of patches adds support for x509 certificates signed by a CA
that uses NIST P384, P256 or P192 keys for signing. It also adds support for
certificates where the public key is one of this type of a key. The math
for ECDSA signature verification is also added as well as the math for fast
mmod operation for NIST P384.

Since self-signed certificates are verified upon loading, the following
script can be used for testing of NIST P256 keys:

k=$(keyctl newring test @u)

while :; do
	for hash in sha1 sha224 sha256 sha384 sha512; do
		openssl req \
			-x509 \
			-${hash} \
			-newkey ec \
			-pkeyopt ec_paramgen_curve:prime256v1 \
			-keyout key.pem \
			-days 365 \
			-subj '/CN=test' \
			-nodes \
			-outform der \
			-out cert.der
		keyctl padd asymmetric testkey $k < cert.der
		if [ $? -ne 0 ]; then
			echo "ERROR"
			exit 1

Ecdsa support also works with restricted keyrings where an RSA key is used
to sign a NIST P384/256/192 key. Scripts for testing are here:


The ECDSA signature verification will be used by IMA Appraisal where ECDSA
file signatures stored in RPM packages will use substantially less space
than if RSA signatures were to be used.

Further, a patch is added that allows kernel modules to be signed with a NIST
P384 key.

Testing was also done with a Pkcs11 device using an ECC key for module

   Stefan and Saulo

  - Added Jarkko's Acked-by's

  - Addressed Jarkko's comments
  - Split off OID definitions from first patch into own patch
  - Renamed OID_id_secp384r1 to OID_id_ansip384r1 (spec name) in 09/10

  - rearranged order of patches to have crypto patches first
  - moved hunk from patch 3 to patch 2 to avoid compilation warning due to
    unused symbol

  - Appended Saulo's patches
  - Appended patch to support kernel modules signed with NIST p384 key. This
    patch requires Nayna's series here: https://lkml.org/lkml/2021/2/18/856

  - patch 3/4: Do not determine key algo using parse_OID in public_key.c
    but do this when parsing the certificate. This addresses an issue
    with certain build configurations where OID_REGISTRY is not available
    as 'Reported-by: kernel test robot <lkp at intel.com>'.

  - Moved some OID defintions to patch 1 for bisectability
  - Applied R-b's
  - moved ecdsa code into its own module ecdsa_generic built from ecdsa.c
  - added script-generated test vectors for NIST P256 & P192 and all hashes
  - parsing of OID that contain header with new parse_oid()

  - registering crypto support under names ecdsa-nist-p256/p192 following
    Hubert Xu's suggestion in other thread
  - appended IMA ECDSA support patch

  - split off of ecdsa crypto part; registering akcipher as "ecdsa" and
    deriving used curve from digits in parsed key

  - patch 2 now includes linux/scatterlist.h

  - using faster vli_sub rather than newly added vli_mod_fast to 'reduce'
  - rearranged switch statements to follow after RSA
  - 3rd patch from 1st posting is now 1st patch

Saulo Alessandre (4):
  crypto: Add NIST P384 curve parameters
  crypto: Add math to support fast NIST P384
  ecdsa: Register NIST P384 and extend test suite
  x509: Add OID for NIST P384 and extend parser for it

Stefan Berger (6):
  oid_registry: Add OIDs for ECDSA with SHA224/256/384/512
  crypto: Add support for ECDSA signature verification
  x509: Detect sm2 keys by their parameters OID
  x509: Add support for parsing x509 certs with ECDSA keys
  ima: Support EC keys for signature verification
  certs: Add support for using elliptic curve keys for signing modules

 certs/Kconfig                             |  22 ++
 certs/Makefile                            |  14 +
 crypto/Kconfig                            |  10 +
 crypto/Makefile                           |   6 +
 crypto/asymmetric_keys/pkcs7_parser.c     |   4 +
 crypto/asymmetric_keys/public_key.c       |   4 +-
 crypto/asymmetric_keys/x509_cert_parser.c |  49 ++-
 crypto/asymmetric_keys/x509_public_key.c  |   4 +-
 crypto/ecc.c                              | 281 +++++++++-----
 crypto/ecc.h                              |  28 +-
 crypto/ecc_curve_defs.h                   |  32 ++
 crypto/ecdsa.c                            | 376 +++++++++++++++++++
 crypto/ecdsasignature.asn1                |   4 +
 crypto/testmgr.c                          |  18 +
 crypto/testmgr.h                          | 424 ++++++++++++++++++++++
 include/crypto/ecdh.h                     |   1 +
 include/keys/asymmetric-type.h            |   6 +
 include/linux/oid_registry.h              |  10 +-
 lib/oid_registry.c                        |  24 ++
 security/integrity/digsig_asymmetric.c    |  30 +-
 20 files changed, 1240 insertions(+), 107 deletions(-)
 create mode 100644 crypto/ecdsa.c
 create mode 100644 crypto/ecdsasignature.asn1


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