[v5,01/10] IMA: Added KEYRING_CHECK func in IMA policy to measure keys
diff mbox series

Message ID 20191111193303.12781-2-nramas@linux.microsoft.com
State New
Headers show
Series
  • KEYS: Measure keys when they are created or updated
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Commit Message

Lakshmi Ramasubramanian Nov. 11, 2019, 7:32 p.m. UTC
IMA policy needs to support a func to enable measurement of
asymmetric keys.

This patch defines a new IMA policy func namely KEYRING_CHECK to
measure asymmetric keys.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
 Documentation/ABI/testing/ima_policy | 6 ++++++
 security/integrity/ima/ima.h         | 1 +
 security/integrity/ima/ima_policy.c  | 4 +++-
 3 files changed, 10 insertions(+), 1 deletion(-)

Comments

Mimi Zohar Nov. 12, 2019, 5:04 p.m. UTC | #1
On Mon, 2019-11-11 at 11:32 -0800, Lakshmi Ramasubramanian wrote:
> IMA policy needs to support a func to enable measurement of
> asymmetric keys.
> 
> This patch defines a new IMA policy func namely KEYRING_CHECK to
> measure asymmetric keys.

This new feature measures "keys" based on policy, not "keyrings".
 Please change the name to KEY_CHECK.

> 
> Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
> ---
>  Documentation/ABI/testing/ima_policy | 6 ++++++
>  security/integrity/ima/ima.h         | 1 +
>  security/integrity/ima/ima_policy.c  | 4 +++-
>  3 files changed, 10 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/ABI/testing/ima_policy b/Documentation/ABI/testing/ima_policy
> index 29aaedf33246..341df49b5ad1 100644
> --- a/Documentation/ABI/testing/ima_policy
> +++ b/Documentation/ABI/testing/ima_policy
> @@ -30,6 +30,7 @@ Description:
>  				[FIRMWARE_CHECK]
>  				[KEXEC_KERNEL_CHECK] [KEXEC_INITRAMFS_CHECK]
>  				[KEXEC_CMDLINE]
> +				[KEYRING_CHECK]
>  			mask:= [[^]MAY_READ] [[^]MAY_WRITE] [[^]MAY_APPEND]
>  			       [[^]MAY_EXEC]
>  			fsmagic:= hex value
> @@ -113,3 +114,8 @@ Description:
>  		Example of appraise rule allowing modsig appended signatures:
>  
>  			appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig|modsig
> +
> +		Example of measure rule using KEYRING_CHECK to measure
> +		all keys:
> +
> +			measure func=KEYRING_CHECK
> diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
> index df4ca482fb53..7f23405b2718 100644
> --- a/security/integrity/ima/ima.h
> +++ b/security/integrity/ima/ima.h
> @@ -193,6 +193,7 @@ static inline unsigned long ima_hash_key(u8 *digest)
>  	hook(KEXEC_INITRAMFS_CHECK)	\
>  	hook(POLICY_CHECK)		\
>  	hook(KEXEC_CMDLINE)		\
> +	hook(KEYRING_CHECK)		\
>  	hook(MAX_CHECK)
>  #define __ima_hook_enumify(ENUM)	ENUM,
>  
> diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
> index f19a895ad7cd..9ca32ffaaa9d 100644
> --- a/security/integrity/ima/ima_policy.c
> +++ b/security/integrity/ima/ima_policy.c
> @@ -373,7 +373,7 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
>  {
>  	int i;
>  
> -	if (func == KEXEC_CMDLINE) {
> +	if ((func == KEXEC_CMDLINE) || (func == KEYRING_CHECK)) {
>  		if ((rule->flags & IMA_FUNC) && (rule->func == func))
>  			return true;
>  		return false;
> @@ -997,6 +997,8 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
>  				entry->func = POLICY_CHECK;
>  			else if (strcmp(args[0].from, "KEXEC_CMDLINE") == 0)
>  				entry->func = KEXEC_CMDLINE;
> +			else if (strcmp(args[0].from, "KEYRING_CHECK") == 0)
> +				entry->func = KEYRING_CHECK;
>  			else
>  				result = -EINVAL;
>  			if (!result)
Lakshmi Ramasubramanian Nov. 12, 2019, 5:37 p.m. UTC | #2
On 11/12/2019 9:04 AM, Mimi Zohar wrote:

> On Mon, 2019-11-11 at 11:32 -0800, Lakshmi Ramasubramanian wrote:
>> IMA policy needs to support a func to enable measurement of
>> asymmetric keys.
>>
>> This patch defines a new IMA policy func namely KEYRING_CHECK to
>> measure asymmetric keys.
> 
> This new feature measures "keys" based on policy, not "keyrings".
>   Please change the name to KEY_CHECK.

Good point - I will change the func name to KEY_CHECK.

  -lakshmi

Patch
diff mbox series

diff --git a/Documentation/ABI/testing/ima_policy b/Documentation/ABI/testing/ima_policy
index 29aaedf33246..341df49b5ad1 100644
--- a/Documentation/ABI/testing/ima_policy
+++ b/Documentation/ABI/testing/ima_policy
@@ -30,6 +30,7 @@  Description:
 				[FIRMWARE_CHECK]
 				[KEXEC_KERNEL_CHECK] [KEXEC_INITRAMFS_CHECK]
 				[KEXEC_CMDLINE]
+				[KEYRING_CHECK]
 			mask:= [[^]MAY_READ] [[^]MAY_WRITE] [[^]MAY_APPEND]
 			       [[^]MAY_EXEC]
 			fsmagic:= hex value
@@ -113,3 +114,8 @@  Description:
 		Example of appraise rule allowing modsig appended signatures:
 
 			appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig|modsig
+
+		Example of measure rule using KEYRING_CHECK to measure
+		all keys:
+
+			measure func=KEYRING_CHECK
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index df4ca482fb53..7f23405b2718 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -193,6 +193,7 @@  static inline unsigned long ima_hash_key(u8 *digest)
 	hook(KEXEC_INITRAMFS_CHECK)	\
 	hook(POLICY_CHECK)		\
 	hook(KEXEC_CMDLINE)		\
+	hook(KEYRING_CHECK)		\
 	hook(MAX_CHECK)
 #define __ima_hook_enumify(ENUM)	ENUM,
 
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index f19a895ad7cd..9ca32ffaaa9d 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -373,7 +373,7 @@  static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
 {
 	int i;
 
-	if (func == KEXEC_CMDLINE) {
+	if ((func == KEXEC_CMDLINE) || (func == KEYRING_CHECK)) {
 		if ((rule->flags & IMA_FUNC) && (rule->func == func))
 			return true;
 		return false;
@@ -997,6 +997,8 @@  static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
 				entry->func = POLICY_CHECK;
 			else if (strcmp(args[0].from, "KEXEC_CMDLINE") == 0)
 				entry->func = KEXEC_CMDLINE;
+			else if (strcmp(args[0].from, "KEYRING_CHECK") == 0)
+				entry->func = KEYRING_CHECK;
 			else
 				result = -EINVAL;
 			if (!result)