diff mbox series

[v4,1/2] integrity, KEYS: add a reference to platform keyring

Message ID 20190118091733.29940-2-kasong@redhat.com (mailing list archive)
State New, archived
Headers show
Series let kexec_file_load use platform keyring to verify the kernel image | expand

Commit Message

Kairui Song Jan. 18, 2019, 9:17 a.m. UTC
commit 9dc92c45177a ('integrity: Define a trusted platform keyring')
introduced a .platform keyring for storing preboot keys, used for
verifying kernel images' signature. Currently only IMA-appraisal is able
to use the keyring to verify kernel images that have their signature
stored in xattr.

This patch exposes the .platform keyring, making it accessible for
verifying PE signed kernel images as well.

Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Kairui Song <kasong@redhat.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Tested-by: Mimi Zohar <zohar@linux.ibm.com>
---
 certs/system_keyring.c        | 9 +++++++++
 include/keys/system_keyring.h | 5 +++++
 security/integrity/digsig.c   | 6 ++++++
 3 files changed, 20 insertions(+)

Comments

Nayna Jan. 18, 2019, 2:35 p.m. UTC | #1
On 01/18/2019 04:17 AM, Kairui Song wrote:
> commit 9dc92c45177a ('integrity: Define a trusted platform keyring')
> introduced a .platform keyring for storing preboot keys, used for
> verifying kernel images' signature. Currently only IMA-appraisal is able
> to use the keyring to verify kernel images that have their signature
> stored in xattr.
>
> This patch exposes the .platform keyring, making it accessible for
> verifying PE signed kernel images as well.
>
> Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
> Signed-off-by: Kairui Song <kasong@redhat.com>
> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
> Tested-by: Mimi Zohar <zohar@linux.ibm.com>
> ---
>   certs/system_keyring.c        | 9 +++++++++
>   include/keys/system_keyring.h | 5 +++++
>   security/integrity/digsig.c   | 6 ++++++
>   3 files changed, 20 insertions(+)
>
> diff --git a/certs/system_keyring.c b/certs/system_keyring.c
> index 81728717523d..4690ef9cda8a 100644
> --- a/certs/system_keyring.c
> +++ b/certs/system_keyring.c
> @@ -24,6 +24,9 @@ static struct key *builtin_trusted_keys;
>   #ifdef CONFIG_SECONDARY_TRUSTED_KEYRING
>   static struct key *secondary_trusted_keys;
>   #endif
> +#ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
> +static struct key *platform_trusted_keys;
> +#endif
>   
>   extern __initconst const u8 system_certificate_list[];
>   extern __initconst const unsigned long system_certificate_list_size;
> @@ -265,4 +268,10 @@ int verify_pkcs7_signature(const void *data, size_t len,
>   }
>   EXPORT_SYMBOL_GPL(verify_pkcs7_signature);
>   
> +#ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
> +void __init set_platform_trusted_keys(struct key *keyring) {
> +	platform_trusted_keys = keyring;
> +}
> +#endif
> +
>   #endif /* CONFIG_SYSTEM_DATA_VERIFICATION */
> diff --git a/include/keys/system_keyring.h b/include/keys/system_keyring.h
> index 359c2f936004..9e1b7849b6aa 100644
> --- a/include/keys/system_keyring.h
> +++ b/include/keys/system_keyring.h
> @@ -61,5 +61,10 @@ static inline struct key *get_ima_blacklist_keyring(void)
>   }
>   #endif /* CONFIG_IMA_BLACKLIST_KEYRING */
>   
> +#ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
> +
> +extern void __init set_platform_trusted_keys(struct key* keyring);
> +
> +#endif /* CONFIG_INTEGRITY_PLATFORM_KEYRING */
>   
>   #endif /* _KEYS_SYSTEM_KEYRING_H */
> diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c
> index f45d6edecf99..bfabc2a8111d 100644
> --- a/security/integrity/digsig.c
> +++ b/security/integrity/digsig.c
> @@ -89,6 +89,12 @@ static int __integrity_init_keyring(const unsigned int id, key_perm_t perm,
>   		keyring[id] = NULL;
>   	}
>   
> +#ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
> +	if (id == INTEGRITY_KEYRING_PLATFORM) {

Shouldn't it also check that keyring[id] is not NULL ?

Thanks & Regards,
     - Nayna

> +		set_platform_trusted_keys(keyring[id]);
> +	}
> +#endif
> +
>   	return err;
>   }
>
Kairui Song Jan. 18, 2019, 3:01 p.m. UTC | #2
On Fri, Jan 18, 2019 at 10:36 PM Nayna <nayna@linux.vnet.ibm.com> wrote:
> On 01/18/2019 04:17 AM, Kairui Song wrote:
> > commit 9dc92c45177a ('integrity: Define a trusted platform keyring')
> > introduced a .platform keyring for storing preboot keys, used for
> > verifying kernel images' signature. Currently only IMA-appraisal is able
> > to use the keyring to verify kernel images that have their signature
> > stored in xattr.
> >
> > This patch exposes the .platform keyring, making it accessible for
> > verifying PE signed kernel images as well.
> >
> > Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
> > Signed-off-by: Kairui Song <kasong@redhat.com>
> > Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
> > Tested-by: Mimi Zohar <zohar@linux.ibm.com>
> > ---
> >   certs/system_keyring.c        | 9 +++++++++
> >   include/keys/system_keyring.h | 5 +++++
> >   security/integrity/digsig.c   | 6 ++++++
> >   3 files changed, 20 insertions(+)
> >
> > diff --git a/certs/system_keyring.c b/certs/system_keyring.c
> > index 81728717523d..4690ef9cda8a 100644
> > --- a/certs/system_keyring.c
> > +++ b/certs/system_keyring.c
> > @@ -24,6 +24,9 @@ static struct key *builtin_trusted_keys;
> >   #ifdef CONFIG_SECONDARY_TRUSTED_KEYRING
> >   static struct key *secondary_trusted_keys;
> >   #endif
> > +#ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
> > +static struct key *platform_trusted_keys;
> > +#endif
> >
> >   extern __initconst const u8 system_certificate_list[];
> >   extern __initconst const unsigned long system_certificate_list_size;
> > @@ -265,4 +268,10 @@ int verify_pkcs7_signature(const void *data, size_t len,
> >   }
> >   EXPORT_SYMBOL_GPL(verify_pkcs7_signature);
> >
> > +#ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
> > +void __init set_platform_trusted_keys(struct key *keyring) {
> > +     platform_trusted_keys = keyring;
> > +}
> > +#endif
> > +
> >   #endif /* CONFIG_SYSTEM_DATA_VERIFICATION */
> > diff --git a/include/keys/system_keyring.h b/include/keys/system_keyring.h
> > index 359c2f936004..9e1b7849b6aa 100644
> > --- a/include/keys/system_keyring.h
> > +++ b/include/keys/system_keyring.h
> > @@ -61,5 +61,10 @@ static inline struct key *get_ima_blacklist_keyring(void)
> >   }
> >   #endif /* CONFIG_IMA_BLACKLIST_KEYRING */
> >
> > +#ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
> > +
> > +extern void __init set_platform_trusted_keys(struct key* keyring);
> > +
> > +#endif /* CONFIG_INTEGRITY_PLATFORM_KEYRING */
> >
> >   #endif /* _KEYS_SYSTEM_KEYRING_H */
> > diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c
> > index f45d6edecf99..bfabc2a8111d 100644
> > --- a/security/integrity/digsig.c
> > +++ b/security/integrity/digsig.c
> > @@ -89,6 +89,12 @@ static int __integrity_init_keyring(const unsigned int id, key_perm_t perm,
> >               keyring[id] = NULL;
> >       }
> >
> > +#ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
> > +     if (id == INTEGRITY_KEYRING_PLATFORM) {
>
> Shouldn't it also check that keyring[id] is not NULL ?

Good catch, if it's NULL then platform_trusted_keyring will be set to
NULL as well, which will work just fine as in this case
platform_trusted_keyring is still considered not initialized. I'll add
a sanity check here to check err value just in case.
Thanks for your suggestion!

>
> Thanks & Regards,
>      - Nayna
>
> > +             set_platform_trusted_keys(keyring[id]);
> > +     }
> > +#endif
> > +
> >       return err;
> >   }
> >
>
>
> _______________________________________________
> kexec mailing list
> kexec@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/kexec
diff mbox series

Patch

diff --git a/certs/system_keyring.c b/certs/system_keyring.c
index 81728717523d..4690ef9cda8a 100644
--- a/certs/system_keyring.c
+++ b/certs/system_keyring.c
@@ -24,6 +24,9 @@  static struct key *builtin_trusted_keys;
 #ifdef CONFIG_SECONDARY_TRUSTED_KEYRING
 static struct key *secondary_trusted_keys;
 #endif
+#ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
+static struct key *platform_trusted_keys;
+#endif
 
 extern __initconst const u8 system_certificate_list[];
 extern __initconst const unsigned long system_certificate_list_size;
@@ -265,4 +268,10 @@  int verify_pkcs7_signature(const void *data, size_t len,
 }
 EXPORT_SYMBOL_GPL(verify_pkcs7_signature);
 
+#ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
+void __init set_platform_trusted_keys(struct key *keyring) {
+	platform_trusted_keys = keyring;
+}
+#endif
+
 #endif /* CONFIG_SYSTEM_DATA_VERIFICATION */
diff --git a/include/keys/system_keyring.h b/include/keys/system_keyring.h
index 359c2f936004..9e1b7849b6aa 100644
--- a/include/keys/system_keyring.h
+++ b/include/keys/system_keyring.h
@@ -61,5 +61,10 @@  static inline struct key *get_ima_blacklist_keyring(void)
 }
 #endif /* CONFIG_IMA_BLACKLIST_KEYRING */
 
+#ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
+
+extern void __init set_platform_trusted_keys(struct key* keyring);
+
+#endif /* CONFIG_INTEGRITY_PLATFORM_KEYRING */
 
 #endif /* _KEYS_SYSTEM_KEYRING_H */
diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c
index f45d6edecf99..bfabc2a8111d 100644
--- a/security/integrity/digsig.c
+++ b/security/integrity/digsig.c
@@ -89,6 +89,12 @@  static int __integrity_init_keyring(const unsigned int id, key_perm_t perm,
 		keyring[id] = NULL;
 	}
 
+#ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
+	if (id == INTEGRITY_KEYRING_PLATFORM) {
+		set_platform_trusted_keys(keyring[id]);
+	}
+#endif
+
 	return err;
 }