[PATCH 12/25] IMA: Change internal interfaces to use lsmblobs
Casey Schaufler
casey at schaufler-ca.com
Wed Nov 13 00:09:00 UTC 2019
The IMA interfaces ima_get_action() and ima_match_policy()
call LSM functions that use lsmblobs. Change the IMA functions
to pass the lsmblob to be compatible with the LSM functions.
Reviewed-by: Kees Cook <keescook at chromium.org>
Reviewed-by: John Johansen <john.johansen at canonical.com>
Signed-off-by: Casey Schaufler <casey at schaufler-ca.com>
cc: linux-audit at redhat.com
cc: linux-integrity at vger.kernel.org
---
security/integrity/ima/ima.h | 11 ++++----
security/integrity/ima/ima_api.c | 10 +++----
security/integrity/ima/ima_appraise.c | 4 +--
security/integrity/ima/ima_main.c | 38 +++++++++++----------------
security/integrity/ima/ima_policy.c | 12 ++++-----
5 files changed, 34 insertions(+), 41 deletions(-)
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 5bcd6011ef8c..4226622f50b1 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -205,9 +205,9 @@ extern const char *const func_tokens[];
struct modsig;
/* 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,
- struct ima_template_desc **template_desc);
+int ima_get_action(struct inode *inode, const struct cred *cred,
+ struct lsmblob *blob, 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,
@@ -229,8 +229,9 @@ void ima_free_template_entry(struct ima_template_entry *entry);
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,
+int ima_match_policy(struct inode *inode, const struct cred *cred,
+ struct lsmblob *blob, 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);
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index 610759fe63b8..1ab769fa7df6 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -163,7 +163,7 @@ void ima_add_violation(struct file *file, const unsigned char *filename,
* ima_get_action - appraise & measure decision based on policy.
* @inode: pointer to inode to measure
* @cred: pointer to credentials structure to validate
- * @secid: secid of the task being validated
+ * @blob: LSM data of the task being validated
* @mask: contains the permission mask (MAY_READ, MAY_WRITE, MAY_EXEC,
* MAY_APPEND)
* @func: caller identifier
@@ -181,15 +181,15 @@ void ima_add_violation(struct file *file, const unsigned char *filename,
* Returns IMA_MEASURE, IMA_APPRAISE mask.
*
*/
-int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
- int mask, enum ima_hooks func, int *pcr,
- struct ima_template_desc **template_desc)
+int ima_get_action(struct inode *inode, const struct cred *cred,
+ struct lsmblob *blob, 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, blob, func, mask, flags, pcr,
template_desc);
}
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
index 7288a574459b..bc04c6f4bb20 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -47,15 +47,13 @@ bool is_ima_appraise_enabled(void)
*/
int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func)
{
- u32 secid;
struct lsmblob blob;
if (!ima_appraise)
return 0;
security_task_getsecid(current, &blob);
- lsmblob_secid(&blob, &secid);
- return ima_match_policy(inode, current_cred(), secid, func, mask,
+ return ima_match_policy(inode, current_cred(), &blob, func, mask,
IMA_APPRAISE | IMA_HASH, NULL, NULL);
}
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 305a00a6b087..a8e7e11b1c84 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -190,8 +190,8 @@ void ima_file_free(struct file *file)
}
static int process_measurement(struct file *file, const struct cred *cred,
- u32 secid, char *buf, loff_t size, int mask,
- enum ima_hooks func)
+ struct lsmblob *blob, char *buf, loff_t size,
+ int mask, enum ima_hooks func)
{
struct inode *inode = file_inode(file);
struct integrity_iint_cache *iint = NULL;
@@ -214,7 +214,7 @@ 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, blob, mask, func, &pcr,
&template_desc);
violation_check = ((func == FILE_CHECK || func == MMAP_CHECK) &&
(ima_policy_flag & IMA_MEASURE));
@@ -384,8 +384,7 @@ int ima_file_mmap(struct file *file, unsigned long prot)
if (file && (prot & PROT_EXEC)) {
security_task_getsecid(current, &blob);
- /* scaffolding - until process_measurement changes */
- return process_measurement(file, current_cred(), blob.secid[0],
+ return process_measurement(file, current_cred(), &blob,
NULL, 0, MAY_EXEC, MMAP_CHECK);
}
@@ -411,16 +410,14 @@ int ima_bprm_check(struct linux_binprm *bprm)
struct lsmblob blob;
security_task_getsecid(current, &blob);
- /* scaffolding until process_measurement changes */
- ret = process_measurement(bprm->file, current_cred(), blob.secid[0],
- NULL, 0, MAY_EXEC, BPRM_CHECK);
+ ret = process_measurement(bprm->file, current_cred(), &blob, NULL, 0,
+ MAY_EXEC, BPRM_CHECK);
if (ret)
return ret;
security_cred_getsecid(bprm->cred, &blob);
- /* scaffolding until process_measurement changes */
- return process_measurement(bprm->file, bprm->cred, blob.secid[0],
- NULL, 0, MAY_EXEC, CREDS_CHECK);
+ return process_measurement(bprm->file, bprm->cred, &blob, NULL, 0,
+ MAY_EXEC, CREDS_CHECK);
}
/**
@@ -438,8 +435,7 @@ int ima_file_check(struct file *file, int mask)
struct lsmblob blob;
security_task_getsecid(current, &blob);
- /* scaffolding until process_measurement changes */
- return process_measurement(file, current_cred(), blob.secid[0], NULL, 0,
+ return process_measurement(file, current_cred(), &blob, NULL, 0,
mask & (MAY_READ | MAY_WRITE | MAY_EXEC |
MAY_APPEND), FILE_CHECK);
}
@@ -571,9 +567,8 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size,
func = read_idmap[read_id] ?: FILE_CHECK;
security_task_getsecid(current, &blob);
- /* scaffolding until process_measurement changes */
- return process_measurement(file, current_cred(), blob.secid[0], buf,
- size, MAY_READ, func);
+ return process_measurement(file, current_cred(), &blob, buf, size,
+ MAY_READ, func);
}
/**
@@ -632,13 +627,14 @@ int ima_load_data(enum kernel_load_data_id id)
* @size: size of buffer(in bytes).
* @eventname: event name to be used for the buffer entry.
* @cred: a pointer to a credentials structure for user validation.
- * @secid: the secid of the task to be validated.
+ * @blob: the LSM data of the task to be validated.
*
* Based on policy, the buffer is measured into the ima log.
*/
static void process_buffer_measurement(const void *buf, int size,
const char *eventname,
- const struct cred *cred, u32 secid)
+ const struct cred *cred,
+ struct lsmblob *blob)
{
int ret = 0;
struct ima_template_entry *entry = NULL;
@@ -656,7 +652,7 @@ static void process_buffer_measurement(const void *buf, int size,
int pcr = CONFIG_IMA_MEASURE_PCR_IDX;
int action = 0;
- action = ima_get_action(NULL, cred, secid, 0, KEXEC_CMDLINE, &pcr,
+ action = ima_get_action(NULL, cred, blob, 0, KEXEC_CMDLINE, &pcr,
&template_desc);
if (!(action & IMA_MEASURE))
return;
@@ -691,14 +687,12 @@ static void process_buffer_measurement(const void *buf, int size,
*/
void ima_kexec_cmdline(const void *buf, int size)
{
- u32 secid;
struct lsmblob blob;
if (buf && size != 0) {
security_task_getsecid(current, &blob);
- /* scaffolding */
process_buffer_measurement(buf, size, "kexec-cmdline",
- current_cred(), blob.secid[0]);
+ current_cred(), &blob);
}
}
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index c5417045e165..e863c0d0f9b7 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -368,7 +368,7 @@ int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event,
* Returns true on rule match, false on failure.
*/
static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
- const struct cred *cred, u32 secid,
+ const struct cred *cred, struct lsmblob *blob,
enum ima_hooks func, int mask)
{
int i;
@@ -431,7 +431,6 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
case LSM_SUBJ_USER:
case LSM_SUBJ_ROLE:
case LSM_SUBJ_TYPE:
- lsmblob_init(&blob, secid);
rc = security_filter_rule_match(&blob,
rule->lsm[i].type,
Audit_equal,
@@ -475,7 +474,7 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func)
* @inode: pointer to an inode for which the policy decision is being made
* @cred: pointer to a credentials structure for which the policy decision is
* being made
- * @secid: LSM secid of the task to be validated
+ * @blob: LSM data of the task to be validated
* @func: IMA hook identifier
* @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
* @pcr: set the pcr to extend
@@ -488,8 +487,9 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func)
* list when walking it. Reads are many orders of magnitude more numerous
* 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,
+int ima_match_policy(struct inode *inode, const struct cred *cred,
+ struct lsmblob *blob, enum ima_hooks func, int mask,
+ int flags, int *pcr,
struct ima_template_desc **template_desc)
{
struct ima_rule_entry *entry;
@@ -504,7 +504,7 @@ int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
if (!(entry->action & actmask))
continue;
- if (!ima_match_rules(entry, inode, cred, secid, func, mask))
+ if (!ima_match_rules(entry, inode, cred, blob, func, mask))
continue;
action |= entry->flags & IMA_ACTION_FLAGS;
--
2.20.1
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