This patch modifies existing IMA functions to retrieve the template name
or format specified in a matched policy rule and provide it to
ima_alloc_init_template(). The latter calls ima_get_template_desc()
to obtain the template descriptor to use for creating a new measurement
entry.

Signed-off-by: Roberto Sassu <roberto.sa...@polito.it>
---
 security/integrity/ima/ima.h        | 10 ++++++----
 security/integrity/ima/ima_api.c    | 23 ++++++++++++++---------
 security/integrity/ima/ima_init.c   |  2 +-
 security/integrity/ima/ima_main.c   |  9 ++++++---
 security/integrity/ima/ima_policy.c |  7 ++++++-
 5 files changed, 33 insertions(+), 18 deletions(-)

diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index f72c488..bc7668d 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -130,7 +130,8 @@ static inline unsigned long ima_hash_key(u8 *digest)
 }
 
 /* LIM API function definitions */
-int ima_get_action(struct inode *inode, int mask, int function);
+int ima_get_action(struct inode *inode, int mask, int function,
+                  char **template_name, char **template_fmt);
 int ima_must_measure(struct inode *inode, int mask, int function);
 int ima_collect_measurement(struct integrity_iint_cache *iint,
                            struct file *file,
@@ -139,13 +140,14 @@ int ima_collect_measurement(struct integrity_iint_cache 
*iint,
 void ima_store_measurement(struct integrity_iint_cache *iint, struct file 
*file,
                           const unsigned char *filename,
                           struct evm_ima_xattr_data *xattr_value,
-                          int xattr_len);
+                          int xattr_len, struct ima_template_desc *desc);
 void ima_audit_measurement(struct integrity_iint_cache *iint,
                           const unsigned char *filename);
 int ima_alloc_init_template(struct integrity_iint_cache *iint,
                            struct file *file, const unsigned char *filename,
                            struct evm_ima_xattr_data *xattr_value,
-                           int xattr_len, struct ima_template_entry **entry);
+                           int xattr_len, struct ima_template_desc *desc,
+                           struct ima_template_entry **entry);
 int ima_store_template(struct ima_template_entry *entry, int violation,
                       struct inode *inode, const unsigned char *filename);
 const char *ima_d_path(struct path *path, char **pathbuf);
@@ -160,7 +162,7 @@ struct integrity_iint_cache *integrity_iint_find(struct 
inode *inode);
 enum ima_hooks { FILE_CHECK = 1, MMAP_CHECK, BPRM_CHECK, MODULE_CHECK, 
POST_SETATTR };
 
 int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask,
-                    int flags);
+                    int flags, char **template_name, char **template_fmt);
 void ima_init_policy(void);
 void ima_update_policy(void);
 ssize_t ima_parse_add_rule(char *);
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index f10328d..da70074 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -27,12 +27,15 @@
 int ima_alloc_init_template(struct integrity_iint_cache *iint,
                            struct file *file, const unsigned char *filename,
                            struct evm_ima_xattr_data *xattr_value,
-                           int xattr_len, struct ima_template_entry **entry)
+                           int xattr_len, struct ima_template_desc *desc,
+                           struct ima_template_entry **entry)
 {
-       struct ima_template_desc *template_desc;
+       struct ima_template_desc *template_desc = desc;
        int i, result = 0;
 
-       template_desc = ima_get_template_desc(NULL, NULL);
+       if (template_desc == NULL)
+               template_desc = ima_get_template_desc(NULL, NULL);
+
        *entry = kzalloc(sizeof(**entry) + template_desc->num_fields *
                         sizeof(struct ima_field_data), GFP_NOFS);
        if (!*entry)
@@ -127,7 +130,7 @@ void ima_add_violation(struct file *file, const unsigned 
char *filename,
        atomic_long_inc(&ima_htable.violations);
 
        result = ima_alloc_init_template(NULL, file, filename,
-                                        NULL, 0, &entry);
+                                        NULL, 0, NULL, &entry);
        if (result < 0) {
                result = -ENOMEM;
                goto err_out;
@@ -156,19 +159,21 @@ err_out:
  * Returns IMA_MEASURE, IMA_APPRAISE mask.
  *
  */
-int ima_get_action(struct inode *inode, int mask, int function)
+int ima_get_action(struct inode *inode, int mask, int function,
+                  char **template_name, char **template_fmt)
 {
        int flags = IMA_MEASURE | IMA_AUDIT | IMA_APPRAISE;
 
        if (!ima_appraise)
                flags &= ~IMA_APPRAISE;
 
-       return ima_match_policy(inode, function, mask, flags);
+       return ima_match_policy(inode, function, mask, flags,
+                               template_name, template_fmt);
 }
 
 int ima_must_measure(struct inode *inode, int mask, int function)
 {
-       return ima_match_policy(inode, function, mask, IMA_MEASURE);
+       return ima_match_policy(inode, function, mask, IMA_MEASURE, NULL, NULL);
 }
 
 /*
@@ -245,7 +250,7 @@ int ima_collect_measurement(struct integrity_iint_cache 
*iint,
 void ima_store_measurement(struct integrity_iint_cache *iint,
                           struct file *file, const unsigned char *filename,
                           struct evm_ima_xattr_data *xattr_value,
-                          int xattr_len)
+                          int xattr_len, struct ima_template_desc *desc)
 {
        const char *op = "add_template_measure";
        const char *audit_cause = "ENOMEM";
@@ -258,7 +263,7 @@ void ima_store_measurement(struct integrity_iint_cache 
*iint,
                return;
 
        result = ima_alloc_init_template(iint, file, filename,
-                                        xattr_value, xattr_len, &entry);
+                                        xattr_value, xattr_len, desc, &entry);
        if (result < 0) {
                integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, filename,
                                    op, audit_cause, result, 0);
diff --git a/security/integrity/ima/ima_init.c 
b/security/integrity/ima/ima_init.c
index 15f34bd..8059ec9 100644
--- a/security/integrity/ima/ima_init.c
+++ b/security/integrity/ima/ima_init.c
@@ -69,7 +69,7 @@ static void __init ima_add_boot_aggregate(void)
        }
 
        result = ima_alloc_init_template(iint, NULL, boot_aggregate_name,
-                                        NULL, 0, &entry);
+                                        NULL, 0, NULL, &entry);
        if (result < 0)
                return;
 
diff --git a/security/integrity/ima/ima_main.c 
b/security/integrity/ima/ima_main.c
index 6e1d3db..d1f372e 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -172,6 +172,7 @@ static int process_measurement(struct file *file, const 
char *filename,
        const char *pathname = NULL;
        int rc = -ENOMEM, action, must_appraise, _func;
        struct evm_ima_xattr_data *xattr_value = NULL, **xattr_ptr = NULL;
+       char *custom_template_name = NULL, *custom_template_fmt = NULL;
        int xattr_len = 0;
 
        if (!ima_initialized || !S_ISREG(inode->i_mode))
@@ -181,7 +182,8 @@ static int process_measurement(struct file *file, const 
char *filename,
         * bitmask based on the appraise/audit/measurement policy.
         * Included is the appraise submask.
         */
-       action = ima_get_action(inode, mask, function);
+       action = ima_get_action(inode, mask, function,
+                               &custom_template_name, &custom_template_fmt);
        if (!action)
                return 0;
 
@@ -211,7 +213,8 @@ static int process_measurement(struct file *file, const 
char *filename,
                goto out_digsig;
        }
 
-       template_desc = ima_get_template_desc(NULL, NULL);
+       template_desc = ima_get_template_desc(custom_template_name,
+                                             custom_template_fmt);
        if (strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) == 0) {
                if (action & IMA_APPRAISE_SUBMASK)
                        xattr_ptr = &xattr_value;
@@ -228,7 +231,7 @@ static int process_measurement(struct file *file, const 
char *filename,
 
        if (action & IMA_MEASURE)
                ima_store_measurement(iint, file, pathname,
-                                     xattr_value, xattr_len);
+                                     xattr_value, xattr_len, template_desc);
        if (action & IMA_APPRAISE_SUBMASK)
                rc = ima_appraise_measurement(_func, iint, file, pathname,
                                              xattr_value, xattr_len);
diff --git a/security/integrity/ima/ima_policy.c 
b/security/integrity/ima/ima_policy.c
index df852ec..fee3dc1 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -261,7 +261,7 @@ static int get_subaction(struct ima_rule_entry *rule, int 
func)
  * change.)
  */
 int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask,
-                    int flags)
+                    int flags, char **template_name, char **template_fmt)
 {
        struct ima_rule_entry *entry;
        int action = 0, actmask = flags | (flags << 1);
@@ -274,6 +274,11 @@ int ima_match_policy(struct inode *inode, enum ima_hooks 
func, int mask,
                if (!ima_match_rules(entry, inode, func, mask))
                        continue;
 
+               if (template_name)
+                       *template_name = entry->template_name;
+               if (template_fmt)
+                       *template_fmt = entry->template_fmt;
+
                action |= entry->flags & IMA_ACTION_FLAGS;
 
                action |= entry->action & IMA_DO_MASK;
-- 
1.8.1.4

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