@@ -24,7 +24,7 @@ Description:
[euid=] [fowner=] [fsname=] [subtype=]]
lsm: [[subj_user=] [subj_role=] [subj_type=]
[obj_user=] [obj_role=] [obj_type=]]
- option: [[appraise_type=] [permit_directio]
+ option: [[appraise_type=] [template=] [permit_directio]
[trust_vfs]]
base: func:= [BPRM_CHECK][MMAP_CHECK][CREDS_CHECK][FILE_CHECK][MODULE_CHECK]
@@ -41,6 +41,7 @@ Description:
fowner:= decimal value
lsm: are LSM specific
option: appraise_type:= [imasig]
+ template:= name of an IMA template type (eg, d-ng)
pcr:= decimal value
permit_directio:= allow directio accesses
trust_vfs:= trust VFS-provided hash values
@@ -148,6 +148,7 @@ int ima_init_crypto(void);
void ima_putc(struct seq_file *m, void *data, int datalen);
void ima_print_digest(struct seq_file *m, u8 *digest, u32 size);
struct ima_template_desc *ima_template_desc_current(void);
+struct ima_template_desc *lookup_template_desc(const char *name);
int ima_restore_measurement_entry(struct ima_template_entry *entry);
int ima_restore_measurement_list(loff_t bufsize, void *buf);
int ima_measurements_show(struct seq_file *m, void *v);
@@ -194,7 +195,8 @@ enum ima_hooks {
/* LIM API function definitions */
int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
- int mask, enum ima_hooks func, int *pcr);
+ int mask, enum ima_hooks func, int *pcr,
+ struct ima_template_desc **template_desc);
int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func);
int ima_collect_measurement(struct integrity_iint_cache *iint,
struct file *file, void *buf, loff_t size,
@@ -215,7 +217,8 @@ const char *ima_d_path(const struct path *path, char **pathbuf, char *filename);
/* IMA policy related functions */
int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
- enum ima_hooks func, int mask, int flags, int *pcr);
+ enum ima_hooks func, int mask, int flags, int *pcr,
+ struct ima_template_desc **template_desc);
void ima_init_policy(void);
void ima_update_policy(void);
void ima_update_policy_flag(void);
@@ -164,6 +164,7 @@ void ima_add_violation(struct file *file, const unsigned char *filename,
* MAY_APPEND)
* @func: caller identifier
* @pcr: pointer filled in if matched measure policy sets pcr=
+ * @template_desc: pointer filled in if matched measure policy sets template=
*
* The policy is defined in terms of keypairs:
* subj=, obj=, type=, func=, mask=, fsmagic=
@@ -176,13 +177,15 @@ void ima_add_violation(struct file *file, const unsigned char *filename,
*
*/
int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
- int mask, enum ima_hooks func, int *pcr)
+ int mask, enum ima_hooks func, int *pcr,
+ struct ima_template_desc **template_desc)
{
int flags = IMA_MEASURE | IMA_AUDIT | IMA_APPRAISE | IMA_HASH;
flags &= ima_policy_flag;
- return ima_match_policy(inode, cred, secid, func, mask, flags, pcr);
+ return ima_match_policy(inode, cred, secid, func, mask, flags, pcr,
+ template_desc);
}
/*
@@ -57,7 +57,7 @@ int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func)
security_task_getsecid(current, &secid);
return ima_match_policy(inode, current_cred(), secid, func, mask,
- IMA_APPRAISE | IMA_HASH, NULL);
+ IMA_APPRAISE | IMA_HASH, NULL, NULL);
}
static int ima_fix_xattr(struct dentry *dentry,
@@ -174,7 +174,7 @@ static int process_measurement(struct file *file, const struct cred *cred,
{
struct inode *inode = file_inode(file);
struct integrity_iint_cache *iint = NULL;
- struct ima_template_desc *template_desc;
+ struct ima_template_desc *template_desc = NULL;
char *pathbuf = NULL;
char filename[NAME_MAX];
const char *pathname = NULL;
@@ -192,7 +192,8 @@ static int process_measurement(struct file *file, const struct cred *cred,
* bitmask based on the appraise/audit/measurement policy.
* Included is the appraise submask.
*/
- action = ima_get_action(inode, cred, secid, mask, func, &pcr);
+ action = ima_get_action(inode, cred, secid, mask, func, &pcr,
+ &template_desc);
violation_check = ((func == FILE_CHECK || func == MMAP_CHECK) &&
(ima_policy_flag & IMA_MEASURE));
if (!action && !violation_check)
@@ -275,7 +276,9 @@ static int process_measurement(struct file *file, const struct cred *cred,
goto out_locked;
}
- template_desc = ima_template_desc_current();
+ if (!template_desc)
+ template_desc = ima_template_desc_current();
+
if ((action & IMA_APPRAISE_SUBMASK) ||
strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) != 0)
/* read 'security.ima' */
@@ -82,6 +82,7 @@ struct ima_rule_entry {
} lsm[MAX_LSM_RULES];
char *fsname;
char *subtype;
+ struct ima_template_desc *template;
};
/*
@@ -403,6 +404,7 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func)
* @func: IMA hook identifier
* @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
* @pcr: set the pcr to extend
+ * @template_desc: the template that should be used for this rule
*
* Measure decision based on func/mask/fsmagic and LSM(subj/obj/type)
* conditions.
@@ -412,7 +414,8 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func)
* than writes so ima_match_policy() is classical RCU candidate.
*/
int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
- enum ima_hooks func, int mask, int flags, int *pcr)
+ enum ima_hooks func, int mask, int flags, int *pcr,
+ struct ima_template_desc **template_desc)
{
struct ima_rule_entry *entry;
int action = 0, actmask = flags | (flags << 1);
@@ -444,6 +447,9 @@ int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
if ((pcr) && (entry->flags & IMA_PCR))
*pcr = entry->pcr;
+ if (template_desc && entry->flags & IMA_TEMPLATE)
+ *template_desc = entry->template;
+
if (!actmask)
break;
}
@@ -681,7 +687,7 @@ enum {
Opt_uid_gt, Opt_euid_gt, Opt_fowner_gt,
Opt_uid_lt, Opt_euid_lt, Opt_fowner_lt,
Opt_appraise_type, Opt_permit_directio,
- Opt_pcr, Opt_trust_vfs, Opt_err
+ Opt_pcr, Opt_trust_vfs, Opt_template, Opt_err
};
static const match_table_t policy_tokens = {
@@ -717,6 +723,7 @@ static const match_table_t policy_tokens = {
{Opt_permit_directio, "permit_directio"},
{Opt_pcr, "pcr=%s"},
{Opt_trust_vfs, "trust_vfs"},
+ {Opt_template, "template=%s"},
{Opt_err, NULL}
};
@@ -770,6 +777,7 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
char *from;
char *p;
bool uid_token;
+ struct ima_template_desc *template_desc;
int result = 0;
ab = integrity_audit_log_start(audit_context(), GFP_KERNEL,
@@ -1079,6 +1087,16 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
else
entry->flags |= IMA_PCR;
+ break;
+ case Opt_template:
+ ima_log_string(ab, "template", args[0].from);
+ template_desc = lookup_template_desc(args[0].from);
+ if (!template_desc) {
+ result = -EINVAL;
+ } else {
+ entry->template = template_desc;
+ entry->flags |= IMA_TEMPLATE;
+ }
break;
case Opt_err:
ima_log_string(ab, "UNKNOWN", p);
@@ -1358,6 +1376,8 @@ int ima_policy_show(struct seq_file *m, void *v)
}
}
}
+ if (entry->flags & IMA_TEMPLATE)
+ seq_printf(m, "template=%s ", entry->template->name);
if (entry->flags & IMA_DIGSIG_REQUIRED)
seq_puts(m, "appraise_type=imasig ");
if (entry->flags & IMA_PERMIT_DIRECTIO)
@@ -50,7 +50,6 @@ static const struct ima_template_field supported_fields[] = {
#define MAX_TEMPLATE_NAME_LEN 15
static struct ima_template_desc *ima_template;
-static struct ima_template_desc *lookup_template_desc(const char *name);
static int template_desc_init_fields(const char *template_fmt,
const struct ima_template_field ***fields,
int *num_fields);
@@ -111,16 +110,24 @@ static int __init ima_template_fmt_setup(char *str)
}
__setup("ima_template_fmt=", ima_template_fmt_setup);
-static struct ima_template_desc *lookup_template_desc(const char *name)
+struct ima_template_desc *lookup_template_desc(const char *name)
{
struct ima_template_desc *template_desc;
- int found = 0;
+ int result, found = 0;
rcu_read_lock();
list_for_each_entry_rcu(template_desc, &defined_templates, list) {
if ((strcmp(template_desc->name, name) == 0) ||
(strcmp(template_desc->fmt, name) == 0)) {
- found = 1;
+ /*
+ * template_desc_init_fields() will return immediately
+ * if the template is already initialised
+ */
+ result = template_desc_init_fields(template_desc->fmt,
+ &(template_desc->fields),
+ &(template_desc->num_fields));
+ if (!result)
+ found = 1;
break;
}
}
@@ -37,6 +37,7 @@
#define EVM_IMMUTABLE_DIGSIG 0x08000000
#define IMA_FAIL_UNVERIFIABLE_SIGS 0x10000000
#define IMA_TRUST_VFS 0x20000000
+#define IMA_TEMPLATE 0x40000000
#define IMA_DO_MASK (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
IMA_HASH | IMA_APPRAISE_SUBMASK)
Admins may wish to log different measurements using different IMA templates. Add support for overriding the default template on a per-rule basis. Signed-off-by: Matthew Garrett <mjg59@google.com> --- Sending separately as requested by Mimi. Roberto, I know your approach here was more ambitious in terms of allowing definition of custom policies - let me know what the best way of integrating with your work here is. Documentation/ABI/testing/ima_policy | 3 ++- security/integrity/ima/ima.h | 7 +++++-- security/integrity/ima/ima_api.c | 7 +++++-- security/integrity/ima/ima_appraise.c | 2 +- security/integrity/ima/ima_main.c | 9 ++++++--- security/integrity/ima/ima_policy.c | 24 ++++++++++++++++++++++-- security/integrity/ima/ima_template.c | 15 +++++++++++---- security/integrity/integrity.h | 1 + 8 files changed, 53 insertions(+), 15 deletions(-)