1 files changed, 216 insertions, 63 deletions

diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index d3963de6003..d9cd5ce14d2 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -9,14 +9,68 @@
  * License.
  *
  * File: ima_api.c
- *	Implements must_measure, collect_measurement, store_measurement,
- *	and store_template.
+ *	Implements must_appraise_or_measure, collect_measurement,
+ *	appraise_measurement, store_measurement and store_template.
  */
 #include <linux/module.h>
 #include <linux/slab.h>
-
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/xattr.h>
+#include <linux/evm.h>
+#include <crypto/hash_info.h>
 #include "ima.h"
-static const char *IMA_TEMPLATE_NAME = "ima";
+
+/*
+ * ima_free_template_entry - free an existing template entry
+ */
+void ima_free_template_entry(struct ima_template_entry *entry)
+{
+	int i;
+
+	for (i = 0; i < entry->template_desc->num_fields; i++)
+		kfree(entry->template_data[i].data);
+
+	kfree(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)
+{
+	struct ima_template_desc *template_desc = ima_template_desc_current();
+	int i, result = 0;
+
+	*entry = kzalloc(sizeof(**entry) + template_desc->num_fields *
+			 sizeof(struct ima_field_data), GFP_NOFS);
+	if (!*entry)
+		return -ENOMEM;
+
+	(*entry)->template_desc = template_desc;
+	for (i = 0; i < template_desc->num_fields; i++) {
+		struct ima_template_field *field = template_desc->fields[i];
+		u32 len;
+
+		result = field->field_init(iint, file, filename,
+					   xattr_value, xattr_len,
+					   &((*entry)->template_data[i]));
+		if (result != 0)
+			goto out;
+
+		len = (*entry)->template_data[i].len;
+		(*entry)->template_data_len += sizeof(len);
+		(*entry)->template_data_len += len;
+	}
+	return 0;
+out:
+	ima_free_template_entry(*entry);
+	*entry = NULL;
+	return result;
+}
 
 /*
  * ima_store_template - store ima template measurements
@@ -35,28 +89,35 @@ static const char *IMA_TEMPLATE_NAME = "ima";
  * Returns 0 on success, error code otherwise
  */
 int ima_store_template(struct ima_template_entry *entry,
-		       int violation, struct inode *inode)
+		       int violation, struct inode *inode,
+		       const unsigned char *filename)
 {
-	const char *op = "add_template_measure";
-	const char *audit_cause = "hashing_error";
+	static const char op[] = "add_template_measure";
+	static const char audit_cause[] = "hashing_error";
+	char *template_name = entry->template_desc->name;
 	int result;
-
-	memset(entry->digest, 0, sizeof(entry->digest));
-	entry->template_name = IMA_TEMPLATE_NAME;
-	entry->template_len = sizeof(entry->template);
+	struct {
+		struct ima_digest_data hdr;
+		char digest[TPM_DIGEST_SIZE];
+	} hash;
 
 	if (!violation) {
-		result = ima_calc_template_hash(entry->template_len,
-						&entry->template,
-						entry->digest);
+		int num_fields = entry->template_desc->num_fields;
+
+		/* this function uses default algo */
+		hash.hdr.algo = HASH_ALGO_SHA1;
+		result = ima_calc_field_array_hash(&entry->template_data[0],
+						   entry->template_desc,
+						   num_fields, &hash.hdr);
 		if (result < 0) {
 			integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode,
-					    entry->template_name, op,
+					    template_name, op,
 					    audit_cause, result, 0);
 			return result;
 		}
+		memcpy(entry->digest, hash.hdr.digest, hash.hdr.length);
 	}
-	result = ima_add_template_entry(entry, violation, op, inode);
+	result = ima_add_template_entry(entry, violation, op, inode, filename);
 	return result;
 }
 
@@ -67,60 +128,60 @@ int ima_store_template(struct ima_template_entry *entry,
  * By extending the PCR with 0xFF's instead of with zeroes, the PCR
  * value is invalidated.
  */
-void ima_add_violation(struct inode *inode, const unsigned char *filename,
+void ima_add_violation(struct file *file, const unsigned char *filename,
 		       const char *op, const char *cause)
 {
 	struct ima_template_entry *entry;
+	struct inode *inode = file_inode(file);
 	int violation = 1;
 	int result;
 
 	/* can overflow, only indicator */
 	atomic_long_inc(&ima_htable.violations);
 
-	entry = kmalloc(sizeof(*entry), GFP_KERNEL);
-	if (!entry) {
+	result = ima_alloc_init_template(NULL, file, filename,
+					 NULL, 0, &entry);
+	if (result < 0) {
 		result = -ENOMEM;
 		goto err_out;
 	}
-	memset(&entry->template, 0, sizeof(entry->template));
-	strncpy(entry->template.file_name, filename, IMA_EVENT_NAME_LEN_MAX);
-	result = ima_store_template(entry, violation, inode);
+	result = ima_store_template(entry, violation, inode, filename);
 	if (result < 0)
-		kfree(entry);
+		ima_free_template_entry(entry);
 err_out:
 	integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, filename,
 			    op, cause, result, 0);
 }
 
 /**
- * ima_must_measure - measure decision based on policy.
+ * ima_get_action - appraise & measure decision based on policy.
  * @inode: pointer to inode to measure
  * @mask: contains the permission mask (MAY_READ, MAY_WRITE, MAY_EXECUTE)
- * @function: calling function (FILE_CHECK, BPRM_CHECK, FILE_MMAP)
+ * @function: calling function (FILE_CHECK, BPRM_CHECK, MMAP_CHECK, MODULE_CHECK)
  *
  * The policy is defined in terms of keypairs:
- * 		subj=, obj=, type=, func=, mask=, fsmagic=
+ *		subj=, obj=, type=, func=, mask=, fsmagic=
  *	subj,obj, and type: are LSM specific.
- * 	func: FILE_CHECK | BPRM_CHECK | FILE_MMAP
- * 	mask: contains the permission mask
+ *	func: FILE_CHECK | BPRM_CHECK | MMAP_CHECK | MODULE_CHECK
+ *	mask: contains the permission mask
  *	fsmagic: hex value
  *
- * Must be called with iint->mutex held.
+ * Returns IMA_MEASURE, IMA_APPRAISE mask.
  *
- * Return 0 to measure. Return 1 if already measured.
- * For matching a DONT_MEASURE policy, no policy, or other
- * error, return an error code.
-*/
-int ima_must_measure(struct ima_iint_cache *iint, struct inode *inode,
-		     int mask, int function)
+ */
+int ima_get_action(struct inode *inode, int mask, int function)
 {
-	int must_measure;
+	int flags = IMA_MEASURE | IMA_AUDIT | IMA_APPRAISE;
+
+	if (!ima_appraise)
+		flags &= ~IMA_APPRAISE;
 
-	if (iint && iint->flags & IMA_MEASURED)
-		return 1;
+	return ima_match_policy(inode, function, mask, flags);
+}
 
-	must_measure = ima_match_policy(inode, function, mask);
-	return must_measure ? 0 : -EACCES;
+int ima_must_measure(struct inode *inode, int mask, int function)
+{
+	return ima_match_policy(inode, function, mask, IMA_MEASURE);
 }
 
 /*
@@ -133,18 +194,57 @@ int ima_must_measure(struct ima_iint_cache *iint, struct inode *inode,
  *
  * Return 0 on success, error code otherwise
  */
-int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file)
+int ima_collect_measurement(struct integrity_iint_cache *iint,
+			    struct file *file,
+			    struct evm_ima_xattr_data **xattr_value,
+			    int *xattr_len)
 {
-	int result = -EEXIST;
+	const char *audit_cause = "failed";
+	struct inode *inode = file_inode(file);
+	const char *filename = file->f_dentry->d_name.name;
+	int result = 0;
+	struct {
+		struct ima_digest_data hdr;
+		char digest[IMA_MAX_DIGEST_SIZE];
+	} hash;
+
+	if (xattr_value)
+		*xattr_len = ima_read_xattr(file->f_dentry, xattr_value);
 
-	if (!(iint->flags & IMA_MEASURED)) {
-		u64 i_version = file->f_dentry->d_inode->i_version;
+	if (!(iint->flags & IMA_COLLECTED)) {
+		u64 i_version = file_inode(file)->i_version;
 
-		memset(iint->digest, 0, IMA_DIGEST_SIZE);
-		result = ima_calc_hash(file, iint->digest);
-		if (!result)
-			iint->version = i_version;
+		if (file->f_flags & O_DIRECT) {
+			audit_cause = "failed(directio)";
+			result = -EACCES;
+			goto out;
+		}
+
+		/* use default hash algorithm */
+		hash.hdr.algo = ima_hash_algo;
+
+		if (xattr_value)
+			ima_get_hash_algo(*xattr_value, *xattr_len, &hash.hdr);
+
+		result = ima_calc_file_hash(file, &hash.hdr);
+		if (!result) {
+			int length = sizeof(hash.hdr) + hash.hdr.length;
+			void *tmpbuf = krealloc(iint->ima_hash, length,
+						GFP_NOFS);
+			if (tmpbuf) {
+				iint->ima_hash = tmpbuf;
+				memcpy(iint->ima_hash, &hash, length);
+				iint->version = i_version;
+				iint->flags |= IMA_COLLECTED;
+			} else
+				result = -ENOMEM;
+		}
 	}
+out:
+	if (result)
+		integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode,
+				    filename, "collect_data", audit_cause,
+				    result, 0);
 	return result;
 }
 
@@ -156,36 +256,89 @@ int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file)
  *
  * We only get here if the inode has not already been measured,
  * but the measurement could already exist:
- * 	- multiple copies of the same file on either the same or
+ *	- multiple copies of the same file on either the same or
  *	  different filesystems.
  *	- the inode was previously flushed as well as the iint info,
  *	  containing the hashing info.
  *
  * Must be called with iint->mutex held.
  */
-void ima_store_measurement(struct ima_iint_cache *iint, struct file *file,
-			   const unsigned char *filename)
+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)
 {
-	const char *op = "add_template_measure";
-	const char *audit_cause = "ENOMEM";
+	static const char op[] = "add_template_measure";
+	static const char audit_cause[] = "ENOMEM";
 	int result = -ENOMEM;
-	struct inode *inode = file->f_dentry->d_inode;
+	struct inode *inode = file_inode(file);
 	struct ima_template_entry *entry;
 	int violation = 0;
 
-	entry = kmalloc(sizeof(*entry), GFP_KERNEL);
-	if (!entry) {
+	if (iint->flags & IMA_MEASURED)
+		return;
+
+	result = ima_alloc_init_template(iint, file, filename,
+					 xattr_value, xattr_len, &entry);
+	if (result < 0) {
 		integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, filename,
 				    op, audit_cause, result, 0);
 		return;
 	}
-	memset(&entry->template, 0, sizeof(entry->template));
-	memcpy(entry->template.digest, iint->digest, IMA_DIGEST_SIZE);
-	strncpy(entry->template.file_name, filename, IMA_EVENT_NAME_LEN_MAX);
 
-	result = ima_store_template(entry, violation, inode);
-	if (!result)
+	result = ima_store_template(entry, violation, inode, filename);
+	if (!result || result == -EEXIST)
 		iint->flags |= IMA_MEASURED;
-	else
-		kfree(entry);
+	if (result < 0)
+		ima_free_template_entry(entry);
+}
+
+void ima_audit_measurement(struct integrity_iint_cache *iint,
+			   const unsigned char *filename)
+{
+	struct audit_buffer *ab;
+	char hash[(iint->ima_hash->length * 2) + 1];
+	const char *algo_name = hash_algo_name[iint->ima_hash->algo];
+	char algo_hash[sizeof(hash) + strlen(algo_name) + 2];
+	int i;
+
+	if (iint->flags & IMA_AUDITED)
+		return;
+
+	for (i = 0; i < iint->ima_hash->length; i++)
+		hex_byte_pack(hash + (i * 2), iint->ima_hash->digest[i]);
+	hash[i * 2] = '\0';
+
+	ab = audit_log_start(current->audit_context, GFP_KERNEL,
+			     AUDIT_INTEGRITY_RULE);
+	if (!ab)
+		return;
+
+	audit_log_format(ab, "file=");
+	audit_log_untrustedstring(ab, filename);
+	audit_log_format(ab, " hash=");
+	snprintf(algo_hash, sizeof(algo_hash), "%s:%s", algo_name, hash);
+	audit_log_untrustedstring(ab, algo_hash);
+
+	audit_log_task_info(ab, current);
+	audit_log_end(ab);
+
+	iint->flags |= IMA_AUDITED;
+}
+
+const char *ima_d_path(struct path *path, char **pathbuf)
+{
+	char *pathname = NULL;
+
+	/* We will allow 11 spaces for ' (deleted)' to be appended */
+	*pathbuf = kmalloc(PATH_MAX + 11, GFP_KERNEL);
+	if (*pathbuf) {
+		pathname = d_path(path, *pathbuf, PATH_MAX + 11);
+		if (IS_ERR(pathname)) {
+			kfree(*pathbuf);
+			*pathbuf = NULL;
+			pathname = NULL;
+		}
+	}
+	return pathname ?: (const char *)path->dentry->d_name.name;
 }