[PATCH v2 0/6] Enable loading local and third party keys on PowerVM guest

[PATCH v2 0/6] Enable loading local and third party keys on PowerVM guest

[Nayna Jain]

On a secure boot enabled PowerVM guest, local and third party code signing
keys are needed to verify signed applications, configuration files, and
kernel modules.

Loading these keys onto either the .secondary_trusted_keys or .ima
keyrings requires the certificates be signed by keys on the
.builtin_trusted_keys, .machine or .secondary_trusted_keys keyrings.

Keys on the .builtin_trusted_keys keyring are trusted because of the chain
of trust from secure boot up to and including the linux kernel.  Keys on
the .machine keyring that derive their trust from an entity such as a
security officer, administrator, system owner, or machine owner are said
to have "imputed trust." The type of certificates and the mechanism for
loading them onto the .machine keyring is platform dependent.

Userspace may load certificates onto the .secondary_trusted_keys or .ima
keyrings. However, keys may also need to be loaded by the kernel if they
are needed for verification in early boot time. On PowerVM guest, third
party code signing keys are loaded from the moduledb variable in the
Platform KeyStore(PKS) onto the .secondary_trusted_keys.

The purpose of this patch set is to allow loading of local and third party
code signing keys on PowerVM.

Changelog:

v2:

* Patch 5/6: Update CA restriction to allow only key signing CA's.
* Rebase on Jarkko's master tree - https://kernel.googlesource.com/pub/scm/linux/kernel/git/jarkko/linux-tpmdd
* Tested after reverting cfa7522f280aa95 because of build failure due to
this commit.

Nayna Jain (6):
  integrity: PowerVM support for loading CA keys on machine keyring
  integrity: ignore keys failing CA restrictions on non-UEFI platform
  integrity: remove global variable from machine_keyring.c
  integrity: check whether imputed trust is enabled
  integrity: PowerVM machine keyring enablement
  integrity: PowerVM support for loading third party code signing keys

 certs/system_keyring.c                        | 23 +++++++++++++
 include/keys/system_keyring.h                 |  7 ++++
 security/integrity/Kconfig                    |  4 ++-
 security/integrity/digsig.c                   |  2 +-
 security/integrity/integrity.h                |  6 ++--
 .../platform_certs/keyring_handler.c          | 19 ++++++++++-
 .../platform_certs/keyring_handler.h          | 10 ++++++
 .../integrity/platform_certs/load_powerpc.c   | 33 +++++++++++++++++++
 .../platform_certs/machine_keyring.c          | 22 ++++++++++---
 9 files changed, 117 insertions(+), 9 deletions(-)

-- 
2.31.1

[PATCH v2 1/6] integrity: PowerVM support for loading CA keys on machine keyring

[Nayna Jain]

Keys that derive their trust from an entity such as a security officer,
administrator, system owner, or machine owner are said to have "imputed
trust". CA keys with imputed trust can be loaded onto the machine keyring.
The mechanism for loading these keys onto the machine keyring is platform
dependent.

Load keys stored in the variable trustedcadb onto the .machine keyring
on PowerVM platform.

Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Reviewed-and-tested-by: Mimi Zohar <zohar@linux.ibm.com>
---
 .../integrity/platform_certs/keyring_handler.c  |  8 ++++++++
 .../integrity/platform_certs/keyring_handler.h  |  5 +++++
 .../integrity/platform_certs/load_powerpc.c     | 17 +++++++++++++++++
 3 files changed, 30 insertions(+)

diff --git a/security/integrity/platform_certs/keyring_handler.c b/security/integrity/platform_certs/keyring_handler.c
index 8a1124e4d769..1649d047e3b8 100644
--- a/security/integrity/platform_certs/keyring_handler.c
+++ b/security/integrity/platform_certs/keyring_handler.c
@@ -69,6 +69,14 @@ __init efi_element_handler_t get_handler_for_mok(const efi_guid_t *sig_type)
 	return NULL;
 }
 
+__init efi_element_handler_t get_handler_for_ca_keys(const efi_guid_t *sig_type)
+{
+	if (efi_guidcmp(*sig_type, efi_cert_x509_guid) == 0)
+		return add_to_machine_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 212d894a8c0c..6f15bb4cc8dc 100644
--- a/security/integrity/platform_certs/keyring_handler.h
+++ b/security/integrity/platform_certs/keyring_handler.h
@@ -29,6 +29,11 @@ efi_element_handler_t get_handler_for_db(const efi_guid_t *sig_type);
  */
 efi_element_handler_t get_handler_for_mok(const efi_guid_t *sig_type);
 
+/*
+ * Return the handler for particular signature list types for CA keys.
+ */
+efi_element_handler_t get_handler_for_ca_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 170789dc63d2..6263ce3b3f1e 100644
--- a/security/integrity/platform_certs/load_powerpc.c
+++ b/security/integrity/platform_certs/load_powerpc.c
@@ -59,6 +59,7 @@ static __init void *get_cert_list(u8 *key, unsigned long keylen, u64 *size)
 static int __init load_powerpc_certs(void)
 {
 	void *db = NULL, *dbx = NULL, *data = NULL;
+	void *trustedca = NULL;
 	u64 dsize = 0;
 	u64 offset = 0;
 	int rc = 0;
@@ -120,6 +121,22 @@ static int __init load_powerpc_certs(void)
 		kfree(data);
 	}
 
+	data = get_cert_list("trustedcadb", 12,  &dsize);
+	if (!data) {
+		pr_info("Couldn't get trustedcadb list from firmware\n");
+	} else if (IS_ERR(data)) {
+		rc = PTR_ERR(data);
+		pr_err("Error reading trustedcadb from firmware: %d\n", rc);
+	} else {
+		extract_esl(trustedca, data, dsize, offset);
+
+		rc = parse_efi_signature_list("powerpc:trustedca", trustedca, dsize,
+					      get_handler_for_ca_keys);
+		if (rc)
+			pr_err("Couldn't parse trustedcadb signatures: %d\n", rc);
+		kfree(data);
+	}
+
 	return rc;
 }
 late_initcall(load_powerpc_certs);
-- 
2.31.1

[PATCH v2 2/6] integrity: ignore keys failing CA restrictions on non-UEFI platform

[Nayna Jain]

On non-UEFI platforms, handle restrict_link_by_ca failures differently.

Certificates which do not satisfy CA restrictions on non-UEFI platforms
are ignored.

Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Reviewed-and-tested-by: Mimi Zohar <zohar@linux.ibm.com>
---
 security/integrity/platform_certs/machine_keyring.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/security/integrity/platform_certs/machine_keyring.c b/security/integrity/platform_certs/machine_keyring.c
index 7aaed7950b6e..389a6e7c9245 100644
--- a/security/integrity/platform_certs/machine_keyring.c
+++ b/security/integrity/platform_certs/machine_keyring.c
@@ -36,7 +36,7 @@ void __init add_to_machine_keyring(const char *source, const void *data, size_t
 	 * If the restriction check does not pass and the platform keyring
 	 * is configured, try to add it into that keyring instead.
 	 */
-	if (rc && IS_ENABLED(CONFIG_INTEGRITY_PLATFORM_KEYRING))
+	if (rc && efi_enabled(EFI_BOOT) && IS_ENABLED(CONFIG_INTEGRITY_PLATFORM_KEYRING))
 		rc = integrity_load_cert(INTEGRITY_KEYRING_PLATFORM, source,
 					 data, len, perm);
 
-- 
2.31.1

[PATCH v2 3/6] integrity: remove global variable from machine_keyring.c

[Nayna Jain]

trust_mok variable is accessed within a single function locally.

Change trust_mok from global to local static variable.

Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Reviewed-and-tested-by: Mimi Zohar <zohar@linux.ibm.com>
---
 security/integrity/platform_certs/machine_keyring.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/security/integrity/platform_certs/machine_keyring.c b/security/integrity/platform_certs/machine_keyring.c
index 389a6e7c9245..9482e16cb2ca 100644
--- a/security/integrity/platform_certs/machine_keyring.c
+++ b/security/integrity/platform_certs/machine_keyring.c
@@ -8,8 +8,6 @@
 #include <linux/efi.h>
 #include "../integrity.h"
 
-static bool trust_mok;
-
 static __init int machine_keyring_init(void)
 {
 	int rc;
@@ -65,9 +63,11 @@ static __init bool uefi_check_trust_mok_keys(void)
 bool __init trust_moklist(void)
 {
 	static bool initialized;
+	static bool trust_mok;
 
 	if (!initialized) {
 		initialized = true;
+		trust_mok = false;
 
 		if (uefi_check_trust_mok_keys())
 			trust_mok = true;
-- 
2.31.1

Re: [PATCH v2 3/6] integrity: remove global variable from machine_keyring.c

[Jarkko Sakkinen]

On Wed Aug 9, 2023 at 10:53 PM EEST, Nayna Jain wrote:
> trust_mok variable is accessed within a single function locally.
>
> Change trust_mok from global to local static variable.
>
> Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
> Reviewed-and-tested-by: Mimi Zohar <zohar@linux.ibm.com>
> ---
>  security/integrity/platform_certs/machine_keyring.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/security/integrity/platform_certs/machine_keyring.c b/security/integrity/platform_certs/machine_keyring.c
> index 389a6e7c9245..9482e16cb2ca 100644
> --- a/security/integrity/platform_certs/machine_keyring.c
> +++ b/security/integrity/platform_certs/machine_keyring.c
> @@ -8,8 +8,6 @@
>  #include <linux/efi.h>
>  #include "../integrity.h"
>  
> -static bool trust_mok;
> -
>  static __init int machine_keyring_init(void)
>  {
>  	int rc;
> @@ -65,9 +63,11 @@ static __init bool uefi_check_trust_mok_keys(void)
>  bool __init trust_moklist(void)
>  {
>  	static bool initialized;
> +	static bool trust_mok;
>  
>  	if (!initialized) {
>  		initialized = true;
> +		trust_mok = false;
>  
>  		if (uefi_check_trust_mok_keys())
>  			trust_mok = true;

Nice catch.

Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>

BR, Jarkko

[PATCH v2 4/6] integrity: check whether imputed trust is enabled

[Nayna Jain]

trust_moklist() is specific to UEFI enabled systems. Other platforms
rely only on the Kconfig.

Define a generic wrapper named imputed_trust_enabled().

Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Reviewed-off-by: Mimi Zohar <zohar@linux.ibm.com>
---
 security/integrity/digsig.c                    |  2 +-
 security/integrity/integrity.h                 |  5 +++--
 .../integrity/platform_certs/keyring_handler.c |  3 ++-
 .../integrity/platform_certs/machine_keyring.c | 18 ++++++++++++++++--
 4 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c
index d0704b1597d4..df387de29bfa 100644
--- a/security/integrity/digsig.c
+++ b/security/integrity/digsig.c
@@ -113,7 +113,7 @@ static int __init __integrity_init_keyring(const unsigned int id,
 	} else {
 		if (id == INTEGRITY_KEYRING_PLATFORM)
 			set_platform_trusted_keys(keyring[id]);
-		if (id == INTEGRITY_KEYRING_MACHINE && trust_moklist())
+		if (id == INTEGRITY_KEYRING_MACHINE && imputed_trust_enabled())
 			set_machine_trusted_keys(keyring[id]);
 		if (id == INTEGRITY_KEYRING_IMA)
 			load_module_cert(keyring[id]);
diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h
index 7167a6e99bdc..d7553c93f5c0 100644
--- a/security/integrity/integrity.h
+++ b/security/integrity/integrity.h
@@ -320,13 +320,14 @@ static inline void __init add_to_platform_keyring(const char *source,
 
 #ifdef CONFIG_INTEGRITY_MACHINE_KEYRING
 void __init add_to_machine_keyring(const char *source, const void *data, size_t len);
-bool __init trust_moklist(void);
+bool __init imputed_trust_enabled(void);
 #else
 static inline void __init add_to_machine_keyring(const char *source,
 						  const void *data, size_t len)
 {
 }
-static inline bool __init trust_moklist(void)
+
+static inline bool __init imputed_trust_enabled(void)
 {
 	return false;
 }
diff --git a/security/integrity/platform_certs/keyring_handler.c b/security/integrity/platform_certs/keyring_handler.c
index 1649d047e3b8..586027b9a3f5 100644
--- a/security/integrity/platform_certs/keyring_handler.c
+++ b/security/integrity/platform_certs/keyring_handler.c
@@ -61,7 +61,8 @@ __init efi_element_handler_t get_handler_for_db(const efi_guid_t *sig_type)
 __init efi_element_handler_t get_handler_for_mok(const efi_guid_t *sig_type)
 {
 	if (efi_guidcmp(*sig_type, efi_cert_x509_guid) == 0) {
-		if (IS_ENABLED(CONFIG_INTEGRITY_MACHINE_KEYRING) && trust_moklist())
+		if (IS_ENABLED(CONFIG_INTEGRITY_MACHINE_KEYRING) &&
+		    imputed_trust_enabled())
 			return add_to_machine_keyring;
 		else
 			return add_to_platform_keyring;
diff --git a/security/integrity/platform_certs/machine_keyring.c b/security/integrity/platform_certs/machine_keyring.c
index 9482e16cb2ca..a401640a63cd 100644
--- a/security/integrity/platform_certs/machine_keyring.c
+++ b/security/integrity/platform_certs/machine_keyring.c
@@ -34,7 +34,8 @@ void __init add_to_machine_keyring(const char *source, const void *data, size_t
 	 * If the restriction check does not pass and the platform keyring
 	 * is configured, try to add it into that keyring instead.
 	 */
-	if (rc && efi_enabled(EFI_BOOT) && IS_ENABLED(CONFIG_INTEGRITY_PLATFORM_KEYRING))
+	if (rc && efi_enabled(EFI_BOOT) &&
+	    IS_ENABLED(CONFIG_INTEGRITY_PLATFORM_KEYRING))
 		rc = integrity_load_cert(INTEGRITY_KEYRING_PLATFORM, source,
 					 data, len, perm);
 
@@ -60,7 +61,7 @@ static __init bool uefi_check_trust_mok_keys(void)
 	return false;
 }
 
-bool __init trust_moklist(void)
+static bool __init trust_moklist(void)
 {
 	static bool initialized;
 	static bool trust_mok;
@@ -75,3 +76,16 @@ bool __init trust_moklist(void)
 
 	return trust_mok;
 }
+
+/*
+ * Provides platform specific check for trusting imputed keys before loading
+ * on .machine keyring. UEFI systems enable this trust based on a variable,
+ * and for other platforms, it is always enabled.
+ */
+bool __init imputed_trust_enabled(void)
+{
+	if (efi_enabled(EFI_BOOT))
+		return trust_moklist();
+
+	return true;
+}
-- 
2.31.1

[PATCH v2 5/6] integrity: PowerVM machine keyring enablement

[Nayna Jain]

Update Kconfig to enable machine keyring and limit to CA certificates
on PowerVM. Only key signing CA keys are allowed.

Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Reviewed-and-tested-by: Mimi Zohar <zohar@linux.ibm.com>

---
 security/integrity/Kconfig | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/security/integrity/Kconfig b/security/integrity/Kconfig
index ec6e0d789da1..232191ee09e3 100644
--- a/security/integrity/Kconfig
+++ b/security/integrity/Kconfig
@@ -67,7 +67,9 @@ config INTEGRITY_MACHINE_KEYRING
 	depends on SECONDARY_TRUSTED_KEYRING
 	depends on INTEGRITY_ASYMMETRIC_KEYS
 	depends on SYSTEM_BLACKLIST_KEYRING
-	depends on LOAD_UEFI_KEYS
+	depends on LOAD_UEFI_KEYS || LOAD_PPC_KEYS
+	select INTEGRITY_CA_MACHINE_KEYRING if LOAD_PPC_KEYS
+	select INTEGRITY_CA_MACHINE_KEYRING_MAX if LOAD_PPC_KEYS
 	help
 	 If set, provide a keyring to which Machine Owner Keys (MOK) may
 	 be added. This keyring shall contain just MOK keys.  Unlike keys
-- 
2.31.1

Re: [PATCH v2 5/6] integrity: PowerVM machine keyring enablement

[Jarkko Sakkinen]

On Wed Aug 9, 2023 at 10:53 PM EEST, Nayna Jain wrote:
> Update Kconfig to enable machine keyring and limit to CA certificates
> on PowerVM. Only key signing CA keys are allowed.
>
> Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
> Reviewed-and-tested-by: Mimi Zohar <zohar@linux.ibm.com>
>
> ---
>  security/integrity/Kconfig | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/security/integrity/Kconfig b/security/integrity/Kconfig
> index ec6e0d789da1..232191ee09e3 100644
> --- a/security/integrity/Kconfig
> +++ b/security/integrity/Kconfig
> @@ -67,7 +67,9 @@ config INTEGRITY_MACHINE_KEYRING
>  	depends on SECONDARY_TRUSTED_KEYRING
>  	depends on INTEGRITY_ASYMMETRIC_KEYS
>  	depends on SYSTEM_BLACKLIST_KEYRING
> -	depends on LOAD_UEFI_KEYS
> +	depends on LOAD_UEFI_KEYS || LOAD_PPC_KEYS
> +	select INTEGRITY_CA_MACHINE_KEYRING if LOAD_PPC_KEYS
> +	select INTEGRITY_CA_MACHINE_KEYRING_MAX if LOAD_PPC_KEYS
>  	help
>  	 If set, provide a keyring to which Machine Owner Keys (MOK) may
>  	 be added. This keyring shall contain just MOK keys.  Unlike keys
> -- 
> 2.31.1

Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>

BR, Jarkko

[PATCH v2 6/6] integrity: PowerVM support for loading third party code signing keys

[Nayna Jain]

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@linux.ibm.com>
---
 certs/system_keyring.c                        | 23 +++++++++++++++++++
 include/keys/system_keyring.h                 |  7 ++++++
 security/integrity/integrity.h                |  1 +
 .../platform_certs/keyring_handler.c          |  8 +++++++
 .../platform_certs/keyring_handler.h          |  5 ++++
 .../integrity/platform_certs/load_powerpc.c   | 18 ++++++++++++++-
 6 files changed, 61 insertions(+), 1 deletion(-)

diff --git a/certs/system_keyring.c b/certs/system_keyring.c
index b348e0898d34..3435d4936fb2 100644
--- a/certs/system_keyring.c
+++ b/certs/system_keyring.c
@@ -396,3 +396,26 @@ void __init set_platform_trusted_keys(struct key *keyring)
 	platform_trusted_keys = keyring;
 }
 #endif
+
+void __init add_to_secondary_keyring(const char *source, const void *data,
+				     size_t len)
+{
+	key_ref_t key;
+	key_perm_t perm;
+	int rc = 0;
+
+	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)) {
+		rc = PTR_ERR(key);
+		pr_err("Problem loading X.509 certificate %d\n", rc);
+	} else {
+		pr_notice("Loaded X.509 cert '%s'\n",
+			  key_ref_to_ptr(key)->description);
+		key_ref_put(key);
+	}
+}
diff --git a/include/keys/system_keyring.h b/include/keys/system_keyring.h
index 7e2583208820..4188f75d1bac 100644
--- a/include/keys/system_keyring.h
+++ b/include/keys/system_keyring.h
@@ -50,9 +50,16 @@ 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
+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/integrity.h b/security/integrity/integrity.h
index d7553c93f5c0..efaa2eb789ad 100644
--- a/security/integrity/integrity.h
+++ b/security/integrity/integrity.h
@@ -228,6 +228,7 @@ static inline int __init integrity_load_cert(const unsigned int id,
 {
 	return 0;
 }
+
 #endif /* CONFIG_INTEGRITY_SIGNATURE */
 
 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
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 6263ce3b3f1e..32c4e5fbf0fb 100644
--- a/security/integrity/platform_certs/load_powerpc.c
+++ b/security/integrity/platform_certs/load_powerpc.c
@@ -59,7 +59,7 @@ static __init void *get_cert_list(u8 *key, unsigned long keylen, u64 *size)
 static int __init load_powerpc_certs(void)
 {
 	void *db = NULL, *dbx = NULL, *data = NULL;
-	void *trustedca = NULL;
+	void *trustedca = NULL, *moduledb = NULL;
 	u64 dsize = 0;
 	u64 offset = 0;
 	int rc = 0;
@@ -137,6 +137,22 @@ 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

Re: [PATCH v2 6/6] integrity: PowerVM support for loading third party code signing keys

[Jarkko Sakkinen]

On Wed Aug 9, 2023 at 10:53 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).
          ^ space

>
> Load third party code signing keys onto .secondary_trusted_keys keyring.
>
> Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
> ---
>  certs/system_keyring.c                        | 23 +++++++++++++++++++
>  include/keys/system_keyring.h                 |  7 ++++++
>  security/integrity/integrity.h                |  1 +
>  .../platform_certs/keyring_handler.c          |  8 +++++++
>  .../platform_certs/keyring_handler.h          |  5 ++++
>  .../integrity/platform_certs/load_powerpc.c   | 18 ++++++++++++++-
>  6 files changed, 61 insertions(+), 1 deletion(-)
>
> diff --git a/certs/system_keyring.c b/certs/system_keyring.c
> index b348e0898d34..3435d4936fb2 100644
> --- a/certs/system_keyring.c
> +++ b/certs/system_keyring.c
> @@ -396,3 +396,26 @@ void __init set_platform_trusted_keys(struct key *keyring)
>  	platform_trusted_keys = keyring;
>  }
>  #endif
> +

spurious newline character

> +void __init add_to_secondary_keyring(const char *source, const void *data,
> +				     size_t len)

Documentation is lacking, and should be in a single line, as it totals
less than 100 characters.

> +{
> +	key_ref_t key;
> +	key_perm_t perm; the following structure
> +	int rc = 0;

	int rc;

> +
> +	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)) {
> +		rc = PTR_ERR(key);

This helper variable is not very useful.

> +		pr_err("Problem loading X.509 certificate %d\n", rc);

Why pr_err()? What kind of object is "a problem"?

Also X.509 certificates are everywhere. If these are printed to the
klog, how can e.g. an admin deduce the problem over here?

Even without having these log messages at all I could trace the called
function and be informed that some X.509 cert has an issues. Actually
then I could even deduce the location, thanks to call backtrace.

These have a potential to lead into wrong conclusions.

> +	} else {
> +		pr_notice("Loaded X.509 cert '%s'\n",
> +			  key_ref_to_ptr(key)->description);

single line

> +		key_ref_put(key);
> +	}

I'd suggest instead the following structure:

	if (IS_ERR(key)) {
		pr_err("Problem loading X.509 certificate %d\n", PTR_ERR(key));
		return;
	}

	pr_notice("Loaded X.509 cert '%s'\n", key_ref_to_ptr(key)->description);
	key_ref_put(key);
}

BR, Jarkko