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-rw-r--r--security/integrity/ima/ima_api.c154
1 files changed, 117 insertions, 37 deletions
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index 1c03e8f1..c38bbce 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -18,9 +18,59 @@
#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
@@ -39,28 +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";
+ 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_buffer_hash(&entry->template,
- entry->template_len,
- 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;
}
@@ -71,26 +128,26 @@ 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->f_dentry->d_inode;
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);
@@ -138,20 +195,42 @@ int ima_must_measure(struct inode *inode, int mask, int function)
* Return 0 on success, error code otherwise
*/
int ima_collect_measurement(struct integrity_iint_cache *iint,
- struct file *file)
+ struct file *file,
+ struct evm_ima_xattr_data **xattr_value,
+ int *xattr_len)
{
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_COLLECTED)) {
u64 i_version = file_inode(file)->i_version;
- iint->ima_xattr.type = IMA_XATTR_DIGEST;
- result = ima_calc_file_hash(file, iint->ima_xattr.digest);
+ /* 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) {
- iint->version = i_version;
- iint->flags |= IMA_COLLECTED;
+ 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;
}
}
if (result)
@@ -177,7 +256,9 @@ int ima_collect_measurement(struct integrity_iint_cache *iint,
* Must be called with iint->mutex held.
*/
void ima_store_measurement(struct integrity_iint_cache *iint,
- struct file *file, const unsigned char *filename)
+ 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";
@@ -189,37 +270,35 @@ void ima_store_measurement(struct integrity_iint_cache *iint,
if (iint->flags & IMA_MEASURED)
return;
- entry = kmalloc(sizeof(*entry), GFP_KERNEL);
- if (!entry) {
+ 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->ima_xattr.digest, IMA_DIGEST_SIZE);
- strcpy(entry->template.file_name,
- (strlen(filename) > IMA_EVENT_NAME_LEN_MAX) ?
- file->f_dentry->d_name.name : filename);
- result = ima_store_template(entry, violation, inode);
+ result = ima_store_template(entry, violation, inode, filename);
if (!result || result == -EEXIST)
iint->flags |= IMA_MEASURED;
if (result < 0)
- kfree(entry);
+ ima_free_template_entry(entry);
}
void ima_audit_measurement(struct integrity_iint_cache *iint,
const unsigned char *filename)
{
struct audit_buffer *ab;
- char hash[(IMA_DIGEST_SIZE * 2) + 1];
+ 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 < IMA_DIGEST_SIZE; i++)
- hex_byte_pack(hash + (i * 2), iint->ima_xattr.digest[i]);
+ 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,
@@ -230,7 +309,8 @@ void ima_audit_measurement(struct integrity_iint_cache *iint,
audit_log_format(ab, "file=");
audit_log_untrustedstring(ab, filename);
audit_log_format(ab, " hash=");
- audit_log_untrustedstring(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);
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