ima: wrap event related data to the new ima_event_data structure

All event related data has been wrapped into the new 'ima_event_data'
structure. The main benefit of this patch is that a new information
can be made available to template fields initialization functions
by simply adding a new field to the new structure instead of modifying
the definition of those functions.

Changelog:
 - v2:
   - f_dentry replaced with f_path.dentry (Roberto Sassu)
   - removed declaration of temporary variables in template field functions
     when possible (suggested by Dmitry Kasatkin)

Signed-off-by: Roberto Sassu <rsassu@suse.de>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

5 files changed, 61 insertions, 79 deletions

diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 8ee997d..e13ae54 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -52,6 +52,15 @@ extern int ima_used_chip;
 extern int ima_hash_algo;
 extern int ima_appraise;
 
+/* IMA event related data */
+struct ima_event_data {
+	struct integrity_iint_cache *iint;
+	struct file *file;
+	const unsigned char *filename;
+	struct evm_ima_xattr_data *xattr_value;
+	int xattr_len;
+};
+
 /* IMA template field data definition */
 struct ima_field_data {
 	u8 *data;
@@ -61,12 +70,10 @@ struct ima_field_data {
 /* IMA template field definition */
 struct ima_template_field {
 	const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN];
-	int (*field_init) (struct integrity_iint_cache *iint, struct file *file,
-			   const unsigned char *filename,
-			   struct evm_ima_xattr_data *xattr_value,
-			   int xattr_len, struct ima_field_data *field_data);
-	void (*field_show) (struct seq_file *m, enum ima_show_type show,
-			    struct ima_field_data *field_data);
+	int (*field_init)(struct ima_event_data *event_data,
+			  struct ima_field_data *field_data);
+	void (*field_show)(struct seq_file *m, enum ima_show_type show,
+			   struct ima_field_data *field_data);
 };
 
 /* IMA template descriptor definition */
@@ -140,10 +147,8 @@ void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file,
 			   int xattr_len);
 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 ima_alloc_init_template(struct ima_event_data *event_data,
+			    struct ima_template_entry **entry);
 int ima_store_template(struct ima_template_entry *entry, int violation,
 		       struct inode *inode, const unsigned char *filename);
 void ima_free_template_entry(struct ima_template_entry *entry);
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index b8a27c5..5865ea2 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -37,10 +37,8 @@ void ima_free_template_entry(struct ima_template_entry *entry)
 /*
  * ima_alloc_init_template - create and initialize a new template entry
  */
-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 ima_alloc_init_template(struct ima_event_data *event_data,
+			    struct ima_template_entry **entry)
 {
 	struct ima_template_desc *template_desc = ima_template_desc_current();
 	int i, result = 0;
@@ -55,8 +53,7 @@ int ima_alloc_init_template(struct integrity_iint_cache *iint,
 		struct ima_template_field *field = template_desc->fields[i];
 		u32 len;
 
-		result = field->field_init(iint, file, filename,
-					   xattr_value, xattr_len,
+		result = field->field_init(event_data,
 					   &((*entry)->template_data[i]));
 		if (result != 0)
 			goto out;
@@ -133,14 +130,14 @@ void ima_add_violation(struct file *file, const unsigned char *filename,
 {
 	struct ima_template_entry *entry;
 	struct inode *inode = file_inode(file);
+	struct ima_event_data event_data = {NULL, file, filename, NULL, 0};
 	int violation = 1;
 	int result;
 
 	/* can overflow, only indicator */
 	atomic_long_inc(&ima_htable.violations);
 
-	result = ima_alloc_init_template(NULL, file, filename,
-					 NULL, 0, &entry);
+	result = ima_alloc_init_template(&event_data, &entry);
 	if (result < 0) {
 		result = -ENOMEM;
 		goto err_out;
@@ -267,13 +264,14 @@ void ima_store_measurement(struct integrity_iint_cache *iint,
 	int result = -ENOMEM;
 	struct inode *inode = file_inode(file);
 	struct ima_template_entry *entry;
+	struct ima_event_data event_data = {iint, file, filename,
+					    xattr_value, xattr_len};
 	int violation = 0;
 
 	if (iint->flags & IMA_MEASURED)
 		return;
 
-	result = ima_alloc_init_template(iint, file, filename,
-					 xattr_value, xattr_len, &entry);
+	result = ima_alloc_init_template(&event_data, &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 0f4cffd..2c66837 100644
--- a/security/integrity/ima/ima_init.c
+++ b/security/integrity/ima/ima_init.c
@@ -49,6 +49,8 @@ static int __init ima_add_boot_aggregate(void)
 	const char *audit_cause = "ENOMEM";
 	struct ima_template_entry *entry;
 	struct integrity_iint_cache tmp_iint, *iint = &tmp_iint;
+	struct ima_event_data event_data = {iint, NULL, boot_aggregate_name,
+					    NULL, 0};
 	int result = -ENOMEM;
 	int violation = 0;
 	struct {
@@ -70,8 +72,7 @@ static int __init ima_add_boot_aggregate(void)
 		}
 	}
 
-	result = ima_alloc_init_template(iint, NULL, boot_aggregate_name,
-					 NULL, 0, &entry);
+	result = ima_alloc_init_template(&event_data, &entry);
 	if (result < 0) {
 		audit_cause = "alloc_entry";
 		goto err_out;
diff --git a/security/integrity/ima/ima_template_lib.c b/security/integrity/ima/ima_template_lib.c
index bcfc36c..67d5133 100644
--- a/security/integrity/ima/ima_template_lib.c
+++ b/security/integrity/ima/ima_template_lib.c
@@ -195,9 +195,7 @@ static int ima_eventdigest_init_common(u8 *digest, u32 digestsize, u8 hash_algo,
 /*
  * This function writes the digest of an event (with size limit).
  */
-int ima_eventdigest_init(struct integrity_iint_cache *iint, struct file *file,
-			 const unsigned char *filename,
-			 struct evm_ima_xattr_data *xattr_value, int xattr_len,
+int ima_eventdigest_init(struct ima_event_data *event_data,
 			 struct ima_field_data *field_data)
 {
 	struct {
@@ -211,25 +209,25 @@ int ima_eventdigest_init(struct integrity_iint_cache *iint, struct file *file,
 
 	memset(&hash, 0, sizeof(hash));
 
-	if (!iint)		/* recording a violation. */
+	if (!event_data->iint)		/* recording a violation. */
 		goto out;
 
-	if (ima_template_hash_algo_allowed(iint->ima_hash->algo)) {
-		cur_digest = iint->ima_hash->digest;
-		cur_digestsize = iint->ima_hash->length;
+	if (ima_template_hash_algo_allowed(event_data->iint->ima_hash->algo)) {
+		cur_digest = event_data->iint->ima_hash->digest;
+		cur_digestsize = event_data->iint->ima_hash->length;
 		goto out;
 	}
 
-	if (!file)		/* missing info to re-calculate the digest */
+	if (!event_data->file)	/* missing info to re-calculate the digest */
 		return -EINVAL;
 
-	inode = file_inode(file);
+	inode = file_inode(event_data->file);
 	hash.hdr.algo = ima_template_hash_algo_allowed(ima_hash_algo) ?
 	    ima_hash_algo : HASH_ALGO_SHA1;
-	result = ima_calc_file_hash(file, &hash.hdr);
+	result = ima_calc_file_hash(event_data->file, &hash.hdr);
 	if (result) {
 		integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode,
-				    filename, "collect_data",
+				    event_data->filename, "collect_data",
 				    "failed", result, 0);
 		return result;
 	}
@@ -243,48 +241,44 @@ out:
 /*
  * This function writes the digest of an event (without size limit).
  */
-int ima_eventdigest_ng_init(struct integrity_iint_cache *iint,
-			    struct file *file, const unsigned char *filename,
-			    struct evm_ima_xattr_data *xattr_value,
-			    int xattr_len, struct ima_field_data *field_data)
+int ima_eventdigest_ng_init(struct ima_event_data *event_data,
+			    struct ima_field_data *field_data)
 {
 	u8 *cur_digest = NULL, hash_algo = HASH_ALGO_SHA1;
 	u32 cur_digestsize = 0;
 
 	/* If iint is NULL, we are recording a violation. */
-	if (!iint)
+	if (!event_data->iint)
 		goto out;
 
-	cur_digest = iint->ima_hash->digest;
-	cur_digestsize = iint->ima_hash->length;
+	cur_digest = event_data->iint->ima_hash->digest;
+	cur_digestsize = event_data->iint->ima_hash->length;
 
-	hash_algo = iint->ima_hash->algo;
+	hash_algo = event_data->iint->ima_hash->algo;
 out:
 	return ima_eventdigest_init_common(cur_digest, cur_digestsize,
 					   hash_algo, field_data);
 }
 
-static int ima_eventname_init_common(struct integrity_iint_cache *iint,
-				     struct file *file,
-				     const unsigned char *filename,
+static int ima_eventname_init_common(struct ima_event_data *event_data,
 				     struct ima_field_data *field_data,
 				     bool size_limit)
 {
 	const char *cur_filename = NULL;
 	u32 cur_filename_len = 0;
 
-	BUG_ON(filename == NULL && file == NULL);
+	BUG_ON(event_data->filename == NULL && event_data->file == NULL);
 
-	if (filename) {
-		cur_filename = filename;
-		cur_filename_len = strlen(filename);
+	if (event_data->filename) {
+		cur_filename = event_data->filename;
+		cur_filename_len = strlen(event_data->filename);
 
 		if (!size_limit || cur_filename_len <= IMA_EVENT_NAME_LEN_MAX)
 			goto out;
 	}
 
-	if (file) {
-		cur_filename = file->f_path.dentry->d_name.name;
+	if (event_data->file) {
+		cur_filename = event_data->file->f_path.dentry->d_name.name;
 		cur_filename_len = strlen(cur_filename);
 	} else
 		/*
@@ -300,36 +294,30 @@ out:
 /*
  * This function writes the name of an event (with size limit).
  */
-int ima_eventname_init(struct integrity_iint_cache *iint, struct file *file,
-		       const unsigned char *filename,
-		       struct evm_ima_xattr_data *xattr_value, int xattr_len,
+int ima_eventname_init(struct ima_event_data *event_data,
 		       struct ima_field_data *field_data)
 {
-	return ima_eventname_init_common(iint, file, filename,
-					 field_data, true);
+	return ima_eventname_init_common(event_data, field_data, true);
 }
 
 /*
  * This function writes the name of an event (without size limit).
  */
-int ima_eventname_ng_init(struct integrity_iint_cache *iint, struct file *file,
-			  const unsigned char *filename,
-			  struct evm_ima_xattr_data *xattr_value, int xattr_len,
+int ima_eventname_ng_init(struct ima_event_data *event_data,
 			  struct ima_field_data *field_data)
 {
-	return ima_eventname_init_common(iint, file, filename,
-					 field_data, false);
+	return ima_eventname_init_common(event_data, field_data, false);
 }
 
 /*
  *  ima_eventsig_init - include the file signature as part of the template data
  */
-int ima_eventsig_init(struct integrity_iint_cache *iint, struct file *file,
-		      const unsigned char *filename,
-		      struct evm_ima_xattr_data *xattr_value, int xattr_len,
+int ima_eventsig_init(struct ima_event_data *event_data,
 		      struct ima_field_data *field_data)
 {
 	enum data_formats fmt = DATA_FMT_HEX;
+	struct evm_ima_xattr_data *xattr_value = event_data->xattr_value;
+	int xattr_len = event_data->xattr_len;
 	int rc = 0;
 
 	if ((!xattr_value) || (xattr_value->type != EVM_IMA_XATTR_DIGSIG))
diff --git a/security/integrity/ima/ima_template_lib.h b/security/integrity/ima/ima_template_lib.h
index 63f6b52..c344530 100644
--- a/security/integrity/ima/ima_template_lib.h
+++ b/security/integrity/ima/ima_template_lib.h
@@ -26,24 +26,14 @@ void ima_show_template_string(struct seq_file *m, enum ima_show_type show,
 			      struct ima_field_data *field_data);
 void ima_show_template_sig(struct seq_file *m, enum ima_show_type show,
 			   struct ima_field_data *field_data);
-int ima_eventdigest_init(struct integrity_iint_cache *iint, struct file *file,
-			 const unsigned char *filename,
-			 struct evm_ima_xattr_data *xattr_value, int xattr_len,
+int ima_eventdigest_init(struct ima_event_data *event_data,
 			 struct ima_field_data *field_data);
-int ima_eventname_init(struct integrity_iint_cache *iint, struct file *file,
-		       const unsigned char *filename,
-		       struct evm_ima_xattr_data *xattr_value, int xattr_len,
+int ima_eventname_init(struct ima_event_data *event_data,
 		       struct ima_field_data *field_data);
-int ima_eventdigest_ng_init(struct integrity_iint_cache *iint,
-			    struct file *file, const unsigned char *filename,
-			    struct evm_ima_xattr_data *xattr_value,
-			    int xattr_len, struct ima_field_data *field_data);
-int ima_eventname_ng_init(struct integrity_iint_cache *iint, struct file *file,
-			  const unsigned char *filename,
-			  struct evm_ima_xattr_data *xattr_value, int xattr_len,
+int ima_eventdigest_ng_init(struct ima_event_data *event_data,
+			    struct ima_field_data *field_data);
+int ima_eventname_ng_init(struct ima_event_data *event_data,
 			  struct ima_field_data *field_data);
-int ima_eventsig_init(struct integrity_iint_cache *iint, struct file *file,
-		      const unsigned char *filename,
-		      struct evm_ima_xattr_data *xattr_value, int xattr_len,
+int ima_eventsig_init(struct ima_event_data *event_data,
 		      struct ima_field_data *field_data);
 #endif /* __LINUX_IMA_TEMPLATE_LIB_H */