diff mbox series

[RFC,30/30] ima: Set ML template per ima namespace

Message ID 20200818154230.14016-21-krzysztof.struczynski@huawei.com
State New
Headers show
Series None | expand

Commit Message

Krzysztof Struczynski Aug. 18, 2020, 3:42 p.m. UTC
From: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>

Set ML template based on the ima_template string. It can be defined by
the user through kcmd_for_children ima securityfs entry. Acceptable
values are the same as for the ima_template kernel boot parameter.

Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
---
 include/linux/ima.h                   |  1 +
 security/integrity/ima/ima.h          |  1 +
 security/integrity/ima/ima_init.c     |  1 +
 security/integrity/ima/ima_ns.c       | 30 ++++++++++++++++++++++++++-
 security/integrity/ima/ima_template.c | 29 +++++++++++++++-----------
 5 files changed, 49 insertions(+), 13 deletions(-)
diff mbox series

Patch

diff --git a/include/linux/ima.h b/include/linux/ima.h
index 7db4995c66cf..f65d6424e584 100644
--- a/include/linux/ima.h
+++ b/include/linux/ima.h
@@ -211,6 +211,7 @@  struct ima_namespace {
 #ifdef CONFIG_KEYS
 	struct key_tag *key_domain;
 #endif
+	struct ima_template_desc *ima_template;
 } __randomize_layout;
 
 extern struct ima_namespace init_ima_ns;
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index b55d25c2bf63..89cb050d5668 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -177,6 +177,7 @@  int template_desc_init_fields(const char *template_fmt,
 struct ima_template_desc *ima_template_desc_current(void);
 struct ima_template_desc *lookup_template_desc(const char *name);
 bool ima_template_has_modsig(const struct ima_template_desc *ima_template);
+int ima_template_setup(char *str, struct ima_namespace *ima_ns);
 int ima_restore_measurement_entry(struct ima_template_entry *entry);
 int ima_restore_measurement_list(loff_t bufsize, void *buf);
 int ima_measurements_show(struct seq_file *m, void *v);
diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c
index 1668edf3ed32..af77d2c85964 100644
--- a/security/integrity/ima/ima_init.c
+++ b/security/integrity/ima/ima_init.c
@@ -49,6 +49,7 @@  struct ima_namespace init_ima_ns = {
 #ifdef CONFIG_KEYS
 	.key_domain = &init_ima_key_domain,
 #endif
+	.ima_template = NULL,
 };
 EXPORT_SYMBOL(init_ima_ns);
 
diff --git a/security/integrity/ima/ima_ns.c b/security/integrity/ima/ima_ns.c
index 9b9c34e71cc6..05c5f0df8f8f 100644
--- a/security/integrity/ima/ima_ns.c
+++ b/security/integrity/ima/ima_ns.c
@@ -48,6 +48,28 @@  static void dec_ima_namespaces(struct ucounts *ucounts)
 	return dec_ucount(ucounts, UCOUNT_IMA_NAMESPACES);
 }
 
+static int ima_set_ns_template(struct ima_namespace *ima_ns)
+{
+	int result;
+
+	if (!ima_ns->ima_template)
+		ima_ns->ima_template =
+			lookup_template_desc(CONFIG_IMA_DEFAULT_TEMPLATE);
+
+	result = template_desc_init_fields(ima_ns->ima_template->fmt,
+					   &(ima_ns->ima_template->fields),
+					   &(ima_ns->ima_template->num_fields));
+	if (result < 0) {
+		pr_err("template %s init failed, result: %d\n",
+		       (strlen(ima_ns->ima_template->name) ?
+		       ima_ns->ima_template->name :
+		       ima_ns->ima_template->fmt), result);
+		ima_ns->ima_template = NULL;
+	}
+
+	return result;
+}
+
 static int ima_ns_add_boot_aggregate(struct ima_namespace *ima_ns)
 {
 	static const char op[] = "ns_add_boot_aggregate";
@@ -269,6 +291,7 @@  static struct ima_namespace *clone_ima_ns(struct user_namespace *user_ns,
 	ns->policy_path_for_children = NULL;
 	ns->x509_path_for_children = NULL;
 	ns->policy_setup_for_children = NULL;
+	ns->ima_template = NULL;
 
 	INIT_LIST_HEAD(&ns->policy_data->ima_default_rules);
 	INIT_LIST_HEAD(&ns->policy_data->ima_policy_rules);
@@ -444,6 +467,10 @@  static int imans_activate(struct ima_namespace *ima_ns)
 	if (ima_ns->frozen)
 		goto out;
 
+	res = ima_set_ns_template(ima_ns);
+	if (res < 0)
+		goto out;
+
 	res = ima_set_ns_policy(ima_ns);
 	if (res < 0)
 		goto out;
@@ -580,10 +607,11 @@  struct ima_kernel_param {
 	int (*set)(char *val, struct ima_namespace *ima_ns);
 };
 
-/* TODO: add ima_template, ima_template_fmt, ima_hash, ... */
+/* TODO: add ima_template_fmt, ima_hash, ... */
 static const struct ima_kernel_param ima_kernel_params[] = {
 	{"ima_appraise", ima_default_appraise_setup},
 	{"ima_policy", ima_policy_setup},
+	{"ima_template", ima_template_setup},
 };
 static const size_t ima_kernel_params_size = ARRAY_SIZE(ima_kernel_params);
 
diff --git a/security/integrity/ima/ima_template.c b/security/integrity/ima/ima_template.c
index 2020bd5176a4..91339a7e1134 100644
--- a/security/integrity/ima/ima_template.c
+++ b/security/integrity/ima/ima_template.c
@@ -57,8 +57,6 @@  static const struct ima_template_field supported_fields[] = {
  */
 #define MAX_TEMPLATE_NAME_LEN sizeof("d-ng|n-ng|sig|buf|d-modisg|modsig|ns")
 
-static struct ima_template_desc *ima_template;
-
 /**
  * ima_template_has_modsig - Check whether template has modsig-related fields.
  * @ima_template: IMA template to check.
@@ -78,12 +76,12 @@  bool ima_template_has_modsig(const struct ima_template_desc *ima_template)
 	return false;
 }
 
-static int __init ima_template_setup(char *str)
+int ima_template_setup(char *str, struct ima_namespace *ima_ns)
 {
 	struct ima_template_desc *template_desc;
 	int template_len = strlen(str);
 
-	if (ima_template)
+	if (ima_ns->ima_template)
 		return 1;
 
 	ima_init_template_list();
@@ -109,16 +107,21 @@  static int __init ima_template_setup(char *str)
 		return 1;
 	}
 
-	ima_template = template_desc;
+	ima_ns->ima_template = template_desc;
 	return 1;
 }
-__setup("ima_template=", ima_template_setup);
+
+static int __init template_setup(char *str)
+{
+	return ima_template_setup(str, &init_ima_ns);
+}
+__setup("ima_template=", template_setup);
 
 static int __init ima_template_fmt_setup(char *str)
 {
 	int num_templates = ARRAY_SIZE(builtin_templates);
 
-	if (ima_template)
+	if (init_ima_ns.ima_template)
 		return 1;
 
 	if (template_desc_init_fields(str, NULL, NULL) < 0) {
@@ -128,7 +131,7 @@  static int __init ima_template_fmt_setup(char *str)
 	}
 
 	builtin_templates[num_templates - 1].fmt = str;
-	ima_template = builtin_templates + num_templates - 1;
+	init_ima_ns.ima_template = builtin_templates + num_templates - 1;
 
 	return 1;
 }
@@ -247,12 +250,14 @@  void ima_init_template_list(void)
 
 struct ima_template_desc *ima_template_desc_current(void)
 {
-	if (!ima_template) {
+	struct ima_namespace *ima_ns = get_current_ns();
+
+	if (!ima_ns->ima_template) {
 		ima_init_template_list();
-		ima_template =
-		    lookup_template_desc(CONFIG_IMA_DEFAULT_TEMPLATE);
+		ima_ns->ima_template =
+			lookup_template_desc(CONFIG_IMA_DEFAULT_TEMPLATE);
 	}
-	return ima_template;
+	return ima_ns->ima_template;
 }
 
 int __init ima_init_template(void)