[PATCH v4 6/6] integrity: PowerVM support for loading third party code signing keys

Jarkko Sakkinen jarkko at kernel.org
Wed Aug 16 21:11:00 UTC 2023


On Thu Aug 17, 2023 at 12:06 AM EEST, Mimi Zohar wrote:
> On Wed, 2023-08-16 at 23:36 +0300, Jarkko Sakkinen wrote:
> > On Tue Aug 15, 2023 at 2:27 PM EEST, Nayna Jain wrote:
> > > On secure boot enabled PowerVM LPAR, third party code signing keys are
> > > needed during early boot to verify signed third party modules. These
> > > third party keys are stored in moduledb object in the Platform
> > > KeyStore (PKS).
> > >
> > > Load third party code signing keys onto .secondary_trusted_keys keyring.
> > >
> > > Signed-off-by: Nayna Jain <nayna at linux.ibm.com>
> > > ---
> > >  certs/system_keyring.c                        | 30 +++++++++++++++++++
> > >  include/keys/system_keyring.h                 |  4 +++
> > >  .../platform_certs/keyring_handler.c          |  8 +++++
> > >  .../platform_certs/keyring_handler.h          |  5 ++++
> > >  .../integrity/platform_certs/load_powerpc.c   | 17 +++++++++++
> > >  5 files changed, 64 insertions(+)
> > >
> > > diff --git a/certs/system_keyring.c b/certs/system_keyring.c
> > > index b348e0898d34..33841c91f12c 100644
> > > --- a/certs/system_keyring.c
> > > +++ b/certs/system_keyring.c
> > > @@ -152,6 +152,36 @@ static __init struct key_restriction *get_builtin_and_secondary_restriction(void
> > >  
> > >  	return restriction;
> > >  }
> > > +
> > > +/**
> > > + * add_to_secondary_keyring - Add to secondary keyring.
> > > + * @source: Source of key
> > > + * @data: The blob holding the key
> > > + * @len: The length of the data blob
> > > + *
> > > + * Add a key to the secondary keyring. The key must be vouched for by a key in the builtin,
> > > + * machine or secondary keyring itself.
> > > + */
> > > +void __init add_to_secondary_keyring(const char *source, const void *data, size_t len)
> > > +{
> > > +	key_ref_t key;
> > > +	key_perm_t perm;
> > > +
> > > +	perm = (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_VIEW;
> > > +
> > > +	key = key_create_or_update(make_key_ref(secondary_trusted_keys, 1),
> > > +				   "asymmetric",
> > > +				   NULL, data, len, perm,
> > > +				   KEY_ALLOC_NOT_IN_QUOTA);
> > > +	if (IS_ERR(key)) {
> > > +		pr_err("Problem loading X.509 certificate from %s to secondary keyring %ld\n",
> > > +		       source, PTR_ERR(key));
> > > +		return;
> > > +	}
> > > +
> > > +	pr_notice("Loaded X.509 cert '%s'\n", key_ref_to_ptr(key)->description);
> > > +	key_ref_put(key);
> > > +}
> > >  #endif
> > >  #ifdef CONFIG_INTEGRITY_MACHINE_KEYRING
> > >  void __init set_machine_trusted_keys(struct key *keyring)
> > > diff --git a/include/keys/system_keyring.h b/include/keys/system_keyring.h
> > > index 7e2583208820..8365adf842ef 100644
> > > --- a/include/keys/system_keyring.h
> > > +++ b/include/keys/system_keyring.h
> > > @@ -50,9 +50,13 @@ int restrict_link_by_digsig_builtin_and_secondary(struct key *keyring,
> > >  						  const struct key_type *type,
> > >  						  const union key_payload *payload,
> > >  						  struct key *restriction_key);
> > > +void __init add_to_secondary_keyring(const char *source, const void *data, size_t len);
> > >  #else
> > >  #define restrict_link_by_builtin_and_secondary_trusted restrict_link_by_builtin_trusted
> > >  #define restrict_link_by_digsig_builtin_and_secondary restrict_link_by_digsig_builtin
> > > +static inline void __init add_to_secondary_keyring(const char *source, const void *data, size_t len)
> > > +{
> > > +}
> > >  #endif
> > >  
> > >  #ifdef CONFIG_INTEGRITY_MACHINE_KEYRING
> > > diff --git a/security/integrity/platform_certs/keyring_handler.c b/security/integrity/platform_certs/keyring_handler.c
> > > index 586027b9a3f5..13ea17207902 100644
> > > --- a/security/integrity/platform_certs/keyring_handler.c
> > > +++ b/security/integrity/platform_certs/keyring_handler.c
> > > @@ -78,6 +78,14 @@ __init efi_element_handler_t get_handler_for_ca_keys(const efi_guid_t *sig_type)
> > >  	return NULL;
> > >  }
> > >  
> > > +__init efi_element_handler_t get_handler_for_code_signing_keys(const efi_guid_t *sig_type)
> > > +{
> > > +	if (efi_guidcmp(*sig_type, efi_cert_x509_guid) == 0)
> > > +		return add_to_secondary_keyring;
> > > +
> > > +	return NULL;
> > > +}
> > > +
> > >  /*
> > >   * Return the appropriate handler for particular signature list types found in
> > >   * the UEFI dbx and MokListXRT tables.
> > > diff --git a/security/integrity/platform_certs/keyring_handler.h b/security/integrity/platform_certs/keyring_handler.h
> > > index 6f15bb4cc8dc..f92895cc50f6 100644
> > > --- a/security/integrity/platform_certs/keyring_handler.h
> > > +++ b/security/integrity/platform_certs/keyring_handler.h
> > > @@ -34,6 +34,11 @@ efi_element_handler_t get_handler_for_mok(const efi_guid_t *sig_type);
> > >   */
> > >  efi_element_handler_t get_handler_for_ca_keys(const efi_guid_t *sig_type);
> > >  
> > > +/*
> > > + * Return the handler for particular signature list types for code signing keys.
> > > + */
> > > +efi_element_handler_t get_handler_for_code_signing_keys(const efi_guid_t *sig_type);
> > > +
> > >  /*
> > >   * Return the handler for particular signature list types found in the dbx.
> > >   */
> > > diff --git a/security/integrity/platform_certs/load_powerpc.c b/security/integrity/platform_certs/load_powerpc.c
> > > index 339053d9726d..c85febca3343 100644
> > > --- a/security/integrity/platform_certs/load_powerpc.c
> > > +++ b/security/integrity/platform_certs/load_powerpc.c
> > > @@ -60,6 +60,7 @@ static int __init load_powerpc_certs(void)
> > >  {
> > >  	void *db = NULL, *dbx = NULL, *data = NULL;
> > >  	void *trustedca;
> > > +	void *moduledb;
> > >  	u64 dsize = 0;
> > >  	u64 offset = 0;
> > >  	int rc = 0;
> > > @@ -137,6 +138,22 @@ static int __init load_powerpc_certs(void)
> > >  		kfree(data);
> > >  	}
> > >  
> > > +	data = get_cert_list("moduledb", 9,  &dsize);
> > > +	if (!data) {
> > > +		pr_info("Couldn't get moduledb list from firmware\n");
> > > +	} else if (IS_ERR(data)) {
> > > +		rc = PTR_ERR(data);
> > > +		pr_err("Error reading moduledb from firmware: %d\n", rc);
> > > +	} else {
> > > +		extract_esl(moduledb, data, dsize, offset);
> > > +
> > > +		rc = parse_efi_signature_list("powerpc:moduledb", moduledb, dsize,
> > > +					      get_handler_for_code_signing_keys);
> > > +		if (rc)
> > > +			pr_err("Couldn't parse moduledb signatures: %d\n", rc);
> > > +		kfree(data);
> > > +	}
> > > +
> > >  	return rc;
> > >  }
> > >  late_initcall(load_powerpc_certs);
> > > -- 
> > > 2.31.1
> > 
> > Reviewed-by: Jarkko Sakkinen <jarkko at kernel.org>
> > 
> > I can pick this. My last PR did not went too great partly because of
> > mess with tpm_tis but now things are calmer.
>
> Glad things have settled down.  Whatever you prefer is fine.   This
> patch set needs to make it into linux-next as soon as possible.  Please
> don't forget to add Nageswara's "Tested-by" and fix mine on 4/6.
>
> -- 
> thanks,
>
> Mimi

I'll apply the full (v4) patch set tomorrow after I wake up.

BR, Jarkko



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