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-rw-r--r--security/integrity/ima/ima_policy.c807
1 files changed, 807 insertions, 0 deletions
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
new file mode 100644
index 000000000..3997e206f
--- /dev/null
+++ b/security/integrity/ima/ima_policy.c
@@ -0,0 +1,807 @@
+/*
+ * Copyright (C) 2008 IBM Corporation
+ * Author: Mimi Zohar <zohar@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * ima_policy.c
+ * - initialize default measure policy rules
+ *
+ */
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/security.h>
+#include <linux/magic.h>
+#include <linux/parser.h>
+#include <linux/slab.h>
+#include <linux/genhd.h>
+
+#include "ima.h"
+
+/* flags definitions */
+#define IMA_FUNC 0x0001
+#define IMA_MASK 0x0002
+#define IMA_FSMAGIC 0x0004
+#define IMA_UID 0x0008
+#define IMA_FOWNER 0x0010
+#define IMA_FSUUID 0x0020
+#define IMA_INMASK 0x0040
+#define IMA_EUID 0x0080
+
+#define UNKNOWN 0
+#define MEASURE 0x0001 /* same as IMA_MEASURE */
+#define DONT_MEASURE 0x0002
+#define APPRAISE 0x0004 /* same as IMA_APPRAISE */
+#define DONT_APPRAISE 0x0008
+#define AUDIT 0x0040
+
+int ima_policy_flag;
+
+#define MAX_LSM_RULES 6
+enum lsm_rule_types { LSM_OBJ_USER, LSM_OBJ_ROLE, LSM_OBJ_TYPE,
+ LSM_SUBJ_USER, LSM_SUBJ_ROLE, LSM_SUBJ_TYPE
+};
+
+enum policy_types { ORIGINAL_TCB = 1, DEFAULT_TCB };
+
+struct ima_rule_entry {
+ struct list_head list;
+ int action;
+ unsigned int flags;
+ enum ima_hooks func;
+ int mask;
+ unsigned long fsmagic;
+ u8 fsuuid[16];
+ kuid_t uid;
+ kuid_t fowner;
+ struct {
+ void *rule; /* LSM file metadata specific */
+ void *args_p; /* audit value */
+ int type; /* audit type */
+ } lsm[MAX_LSM_RULES];
+};
+
+/*
+ * Without LSM specific knowledge, the default policy can only be
+ * written in terms of .action, .func, .mask, .fsmagic, .uid, and .fowner
+ */
+
+/*
+ * The minimum rule set to allow for full TCB coverage. Measures all files
+ * opened or mmap for exec and everything read by root. Dangerous because
+ * normal users can easily run the machine out of memory simply building
+ * and running executables.
+ */
+static struct ima_rule_entry dont_measure_rules[] = {
+ {.action = DONT_MEASURE, .fsmagic = PROC_SUPER_MAGIC, .flags = IMA_FSMAGIC},
+ {.action = DONT_MEASURE, .fsmagic = SYSFS_MAGIC, .flags = IMA_FSMAGIC},
+ {.action = DONT_MEASURE, .fsmagic = DEBUGFS_MAGIC, .flags = IMA_FSMAGIC},
+ {.action = DONT_MEASURE, .fsmagic = TMPFS_MAGIC, .flags = IMA_FSMAGIC},
+ {.action = DONT_MEASURE, .fsmagic = DEVPTS_SUPER_MAGIC, .flags = IMA_FSMAGIC},
+ {.action = DONT_MEASURE, .fsmagic = BINFMTFS_MAGIC, .flags = IMA_FSMAGIC},
+ {.action = DONT_MEASURE, .fsmagic = SECURITYFS_MAGIC, .flags = IMA_FSMAGIC},
+ {.action = DONT_MEASURE, .fsmagic = SELINUX_MAGIC, .flags = IMA_FSMAGIC},
+ {.action = DONT_MEASURE, .fsmagic = CGROUP_SUPER_MAGIC,
+ .flags = IMA_FSMAGIC},
+ {.action = DONT_MEASURE, .fsmagic = NSFS_MAGIC, .flags = IMA_FSMAGIC}
+};
+
+static struct ima_rule_entry original_measurement_rules[] = {
+ {.action = MEASURE, .func = MMAP_CHECK, .mask = MAY_EXEC,
+ .flags = IMA_FUNC | IMA_MASK},
+ {.action = MEASURE, .func = BPRM_CHECK, .mask = MAY_EXEC,
+ .flags = IMA_FUNC | IMA_MASK},
+ {.action = MEASURE, .func = FILE_CHECK, .mask = MAY_READ,
+ .uid = GLOBAL_ROOT_UID, .flags = IMA_FUNC | IMA_MASK | IMA_UID},
+ {.action = MEASURE, .func = MODULE_CHECK, .flags = IMA_FUNC},
+ {.action = MEASURE, .func = FIRMWARE_CHECK, .flags = IMA_FUNC},
+};
+
+static struct ima_rule_entry default_measurement_rules[] = {
+ {.action = MEASURE, .func = MMAP_CHECK, .mask = MAY_EXEC,
+ .flags = IMA_FUNC | IMA_MASK},
+ {.action = MEASURE, .func = BPRM_CHECK, .mask = MAY_EXEC,
+ .flags = IMA_FUNC | IMA_MASK},
+ {.action = MEASURE, .func = FILE_CHECK, .mask = MAY_READ,
+ .uid = GLOBAL_ROOT_UID, .flags = IMA_FUNC | IMA_INMASK | IMA_EUID},
+ {.action = MEASURE, .func = FILE_CHECK, .mask = MAY_READ,
+ .uid = GLOBAL_ROOT_UID, .flags = IMA_FUNC | IMA_INMASK | IMA_UID},
+ {.action = MEASURE, .func = MODULE_CHECK, .flags = IMA_FUNC},
+ {.action = MEASURE, .func = FIRMWARE_CHECK, .flags = IMA_FUNC},
+};
+
+static struct ima_rule_entry default_appraise_rules[] = {
+ {.action = DONT_APPRAISE, .fsmagic = PROC_SUPER_MAGIC, .flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE, .fsmagic = SYSFS_MAGIC, .flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE, .fsmagic = DEBUGFS_MAGIC, .flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE, .fsmagic = TMPFS_MAGIC, .flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE, .fsmagic = RAMFS_MAGIC, .flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE, .fsmagic = DEVPTS_SUPER_MAGIC, .flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE, .fsmagic = BINFMTFS_MAGIC, .flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE, .fsmagic = SECURITYFS_MAGIC, .flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE, .fsmagic = SELINUX_MAGIC, .flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE, .fsmagic = NSFS_MAGIC, .flags = IMA_FSMAGIC},
+ {.action = DONT_APPRAISE, .fsmagic = CGROUP_SUPER_MAGIC, .flags = IMA_FSMAGIC},
+#ifndef CONFIG_IMA_APPRAISE_SIGNED_INIT
+ {.action = APPRAISE, .fowner = GLOBAL_ROOT_UID, .flags = IMA_FOWNER},
+#else
+ /* force signature */
+ {.action = APPRAISE, .fowner = GLOBAL_ROOT_UID,
+ .flags = IMA_FOWNER | IMA_DIGSIG_REQUIRED},
+#endif
+};
+
+static LIST_HEAD(ima_default_rules);
+static LIST_HEAD(ima_policy_rules);
+static struct list_head *ima_rules;
+
+static DEFINE_MUTEX(ima_rules_mutex);
+
+static int ima_policy __initdata;
+static int __init default_measure_policy_setup(char *str)
+{
+ if (ima_policy)
+ return 1;
+
+ ima_policy = ORIGINAL_TCB;
+ return 1;
+}
+__setup("ima_tcb", default_measure_policy_setup);
+
+static int __init policy_setup(char *str)
+{
+ if (ima_policy)
+ return 1;
+
+ if (strcmp(str, "tcb") == 0)
+ ima_policy = DEFAULT_TCB;
+
+ return 1;
+}
+__setup("ima_policy=", policy_setup);
+
+static bool ima_use_appraise_tcb __initdata;
+static int __init default_appraise_policy_setup(char *str)
+{
+ ima_use_appraise_tcb = 1;
+ return 1;
+}
+__setup("ima_appraise_tcb", default_appraise_policy_setup);
+
+/*
+ * Although the IMA policy does not change, the LSM policy can be
+ * reloaded, leaving the IMA LSM based rules referring to the old,
+ * stale LSM policy.
+ *
+ * Update the IMA LSM based rules to reflect the reloaded LSM policy.
+ * We assume the rules still exist; and BUG_ON() if they don't.
+ */
+static void ima_lsm_update_rules(void)
+{
+ struct ima_rule_entry *entry, *tmp;
+ int result;
+ int i;
+
+ mutex_lock(&ima_rules_mutex);
+ list_for_each_entry_safe(entry, tmp, &ima_policy_rules, list) {
+ for (i = 0; i < MAX_LSM_RULES; i++) {
+ if (!entry->lsm[i].rule)
+ continue;
+ result = security_filter_rule_init(entry->lsm[i].type,
+ Audit_equal,
+ entry->lsm[i].args_p,
+ &entry->lsm[i].rule);
+ BUG_ON(!entry->lsm[i].rule);
+ }
+ }
+ mutex_unlock(&ima_rules_mutex);
+}
+
+/**
+ * ima_match_rules - determine whether an inode matches the measure rule.
+ * @rule: a pointer to a rule
+ * @inode: a pointer to an inode
+ * @func: LIM hook identifier
+ * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
+ *
+ * Returns true on rule match, false on failure.
+ */
+static bool ima_match_rules(struct ima_rule_entry *rule,
+ struct inode *inode, enum ima_hooks func, int mask)
+{
+ struct task_struct *tsk = current;
+ const struct cred *cred = current_cred();
+ int i;
+
+ if ((rule->flags & IMA_FUNC) &&
+ (rule->func != func && func != POST_SETATTR))
+ return false;
+ if ((rule->flags & IMA_MASK) &&
+ (rule->mask != mask && func != POST_SETATTR))
+ return false;
+ if ((rule->flags & IMA_INMASK) &&
+ (!(rule->mask & mask) && func != POST_SETATTR))
+ return false;
+ if ((rule->flags & IMA_FSMAGIC)
+ && rule->fsmagic != inode->i_sb->s_magic)
+ return false;
+ if ((rule->flags & IMA_FSUUID) &&
+ memcmp(rule->fsuuid, inode->i_sb->s_uuid, sizeof(rule->fsuuid)))
+ return false;
+ if ((rule->flags & IMA_UID) && !uid_eq(rule->uid, cred->uid))
+ return false;
+ if (rule->flags & IMA_EUID) {
+ if (has_capability_noaudit(current, CAP_SETUID)) {
+ if (!uid_eq(rule->uid, cred->euid)
+ && !uid_eq(rule->uid, cred->suid)
+ && !uid_eq(rule->uid, cred->uid))
+ return false;
+ } else if (!uid_eq(rule->uid, cred->euid))
+ return false;
+ }
+
+ if ((rule->flags & IMA_FOWNER) && !uid_eq(rule->fowner, inode->i_uid))
+ return false;
+ for (i = 0; i < MAX_LSM_RULES; i++) {
+ int rc = 0;
+ u32 osid, sid;
+ int retried = 0;
+
+ if (!rule->lsm[i].rule)
+ continue;
+retry:
+ switch (i) {
+ case LSM_OBJ_USER:
+ case LSM_OBJ_ROLE:
+ case LSM_OBJ_TYPE:
+ security_inode_getsecid(inode, &osid);
+ rc = security_filter_rule_match(osid,
+ rule->lsm[i].type,
+ Audit_equal,
+ rule->lsm[i].rule,
+ NULL);
+ break;
+ case LSM_SUBJ_USER:
+ case LSM_SUBJ_ROLE:
+ case LSM_SUBJ_TYPE:
+ security_task_getsecid(tsk, &sid);
+ rc = security_filter_rule_match(sid,
+ rule->lsm[i].type,
+ Audit_equal,
+ rule->lsm[i].rule,
+ NULL);
+ default:
+ break;
+ }
+ if ((rc < 0) && (!retried)) {
+ retried = 1;
+ ima_lsm_update_rules();
+ goto retry;
+ }
+ if (!rc)
+ return false;
+ }
+ return true;
+}
+
+/*
+ * In addition to knowing that we need to appraise the file in general,
+ * we need to differentiate between calling hooks, for hook specific rules.
+ */
+static int get_subaction(struct ima_rule_entry *rule, int func)
+{
+ if (!(rule->flags & IMA_FUNC))
+ return IMA_FILE_APPRAISE;
+
+ switch (func) {
+ case MMAP_CHECK:
+ return IMA_MMAP_APPRAISE;
+ case BPRM_CHECK:
+ return IMA_BPRM_APPRAISE;
+ case MODULE_CHECK:
+ return IMA_MODULE_APPRAISE;
+ case FIRMWARE_CHECK:
+ return IMA_FIRMWARE_APPRAISE;
+ case FILE_CHECK:
+ default:
+ return IMA_FILE_APPRAISE;
+ }
+}
+
+/**
+ * ima_match_policy - decision based on LSM and other conditions
+ * @inode: pointer to an inode for which the policy decision is being made
+ * @func: IMA hook identifier
+ * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
+ *
+ * Measure decision based on func/mask/fsmagic and LSM(subj/obj/type)
+ * conditions.
+ *
+ * (There is no need for locking when walking the policy list,
+ * as elements in the list are never deleted, nor does the list
+ * change.)
+ */
+int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask,
+ int flags)
+{
+ struct ima_rule_entry *entry;
+ int action = 0, actmask = flags | (flags << 1);
+
+ list_for_each_entry(entry, ima_rules, list) {
+
+ if (!(entry->action & actmask))
+ continue;
+
+ if (!ima_match_rules(entry, inode, func, mask))
+ continue;
+
+ action |= entry->flags & IMA_ACTION_FLAGS;
+
+ action |= entry->action & IMA_DO_MASK;
+ if (entry->action & IMA_APPRAISE)
+ action |= get_subaction(entry, func);
+
+ if (entry->action & IMA_DO_MASK)
+ actmask &= ~(entry->action | entry->action << 1);
+ else
+ actmask &= ~(entry->action | entry->action >> 1);
+
+ if (!actmask)
+ break;
+ }
+
+ return action;
+}
+
+/*
+ * Initialize the ima_policy_flag variable based on the currently
+ * loaded policy. Based on this flag, the decision to short circuit
+ * out of a function or not call the function in the first place
+ * can be made earlier.
+ */
+void ima_update_policy_flag(void)
+{
+ struct ima_rule_entry *entry;
+
+ ima_policy_flag = 0;
+ list_for_each_entry(entry, ima_rules, list) {
+ if (entry->action & IMA_DO_MASK)
+ ima_policy_flag |= entry->action;
+ }
+
+ if (!ima_appraise)
+ ima_policy_flag &= ~IMA_APPRAISE;
+}
+
+/**
+ * ima_init_policy - initialize the default measure rules.
+ *
+ * ima_rules points to either the ima_default_rules or the
+ * the new ima_policy_rules.
+ */
+void __init ima_init_policy(void)
+{
+ int i, measure_entries, appraise_entries;
+
+ /* if !ima_policy set entries = 0 so we load NO default rules */
+ measure_entries = ima_policy ? ARRAY_SIZE(dont_measure_rules) : 0;
+ appraise_entries = ima_use_appraise_tcb ?
+ ARRAY_SIZE(default_appraise_rules) : 0;
+
+ for (i = 0; i < measure_entries; i++)
+ list_add_tail(&dont_measure_rules[i].list, &ima_default_rules);
+
+ switch (ima_policy) {
+ case ORIGINAL_TCB:
+ for (i = 0; i < ARRAY_SIZE(original_measurement_rules); i++)
+ list_add_tail(&original_measurement_rules[i].list,
+ &ima_default_rules);
+ break;
+ case DEFAULT_TCB:
+ for (i = 0; i < ARRAY_SIZE(default_measurement_rules); i++)
+ list_add_tail(&default_measurement_rules[i].list,
+ &ima_default_rules);
+ default:
+ break;
+ }
+
+ for (i = 0; i < appraise_entries; i++) {
+ list_add_tail(&default_appraise_rules[i].list,
+ &ima_default_rules);
+ }
+
+ ima_rules = &ima_default_rules;
+}
+
+/**
+ * ima_update_policy - update default_rules with new measure rules
+ *
+ * Called on file .release to update the default rules with a complete new
+ * policy. Once updated, the policy is locked, no additional rules can be
+ * added to the policy.
+ */
+void ima_update_policy(void)
+{
+ ima_rules = &ima_policy_rules;
+ ima_update_policy_flag();
+}
+
+enum {
+ Opt_err = -1,
+ Opt_measure = 1, Opt_dont_measure,
+ Opt_appraise, Opt_dont_appraise,
+ Opt_audit,
+ Opt_obj_user, Opt_obj_role, Opt_obj_type,
+ Opt_subj_user, Opt_subj_role, Opt_subj_type,
+ Opt_func, Opt_mask, Opt_fsmagic,
+ Opt_uid, Opt_euid, Opt_fowner,
+ Opt_appraise_type, Opt_fsuuid, Opt_permit_directio
+};
+
+static match_table_t policy_tokens = {
+ {Opt_measure, "measure"},
+ {Opt_dont_measure, "dont_measure"},
+ {Opt_appraise, "appraise"},
+ {Opt_dont_appraise, "dont_appraise"},
+ {Opt_audit, "audit"},
+ {Opt_obj_user, "obj_user=%s"},
+ {Opt_obj_role, "obj_role=%s"},
+ {Opt_obj_type, "obj_type=%s"},
+ {Opt_subj_user, "subj_user=%s"},
+ {Opt_subj_role, "subj_role=%s"},
+ {Opt_subj_type, "subj_type=%s"},
+ {Opt_func, "func=%s"},
+ {Opt_mask, "mask=%s"},
+ {Opt_fsmagic, "fsmagic=%s"},
+ {Opt_fsuuid, "fsuuid=%s"},
+ {Opt_uid, "uid=%s"},
+ {Opt_euid, "euid=%s"},
+ {Opt_fowner, "fowner=%s"},
+ {Opt_appraise_type, "appraise_type=%s"},
+ {Opt_permit_directio, "permit_directio"},
+ {Opt_err, NULL}
+};
+
+static int ima_lsm_rule_init(struct ima_rule_entry *entry,
+ substring_t *args, int lsm_rule, int audit_type)
+{
+ int result;
+
+ if (entry->lsm[lsm_rule].rule)
+ return -EINVAL;
+
+ entry->lsm[lsm_rule].args_p = match_strdup(args);
+ if (!entry->lsm[lsm_rule].args_p)
+ return -ENOMEM;
+
+ entry->lsm[lsm_rule].type = audit_type;
+ result = security_filter_rule_init(entry->lsm[lsm_rule].type,
+ Audit_equal,
+ entry->lsm[lsm_rule].args_p,
+ &entry->lsm[lsm_rule].rule);
+ if (!entry->lsm[lsm_rule].rule) {
+ kfree(entry->lsm[lsm_rule].args_p);
+ return -EINVAL;
+ }
+
+ return result;
+}
+
+static void ima_log_string(struct audit_buffer *ab, char *key, char *value)
+{
+ audit_log_format(ab, "%s=", key);
+ audit_log_untrustedstring(ab, value);
+ audit_log_format(ab, " ");
+}
+
+static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
+{
+ struct audit_buffer *ab;
+ char *from;
+ char *p;
+ int result = 0;
+
+ ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_INTEGRITY_RULE);
+
+ entry->uid = INVALID_UID;
+ entry->fowner = INVALID_UID;
+ entry->action = UNKNOWN;
+ while ((p = strsep(&rule, " \t")) != NULL) {
+ substring_t args[MAX_OPT_ARGS];
+ int token;
+ unsigned long lnum;
+
+ if (result < 0)
+ break;
+ if ((*p == '\0') || (*p == ' ') || (*p == '\t'))
+ continue;
+ token = match_token(p, policy_tokens, args);
+ switch (token) {
+ case Opt_measure:
+ ima_log_string(ab, "action", "measure");
+
+ if (entry->action != UNKNOWN)
+ result = -EINVAL;
+
+ entry->action = MEASURE;
+ break;
+ case Opt_dont_measure:
+ ima_log_string(ab, "action", "dont_measure");
+
+ if (entry->action != UNKNOWN)
+ result = -EINVAL;
+
+ entry->action = DONT_MEASURE;
+ break;
+ case Opt_appraise:
+ ima_log_string(ab, "action", "appraise");
+
+ if (entry->action != UNKNOWN)
+ result = -EINVAL;
+
+ entry->action = APPRAISE;
+ break;
+ case Opt_dont_appraise:
+ ima_log_string(ab, "action", "dont_appraise");
+
+ if (entry->action != UNKNOWN)
+ result = -EINVAL;
+
+ entry->action = DONT_APPRAISE;
+ break;
+ case Opt_audit:
+ ima_log_string(ab, "action", "audit");
+
+ if (entry->action != UNKNOWN)
+ result = -EINVAL;
+
+ entry->action = AUDIT;
+ break;
+ case Opt_func:
+ ima_log_string(ab, "func", args[0].from);
+
+ if (entry->func)
+ result = -EINVAL;
+
+ if (strcmp(args[0].from, "FILE_CHECK") == 0)
+ entry->func = FILE_CHECK;
+ /* PATH_CHECK is for backwards compat */
+ else if (strcmp(args[0].from, "PATH_CHECK") == 0)
+ entry->func = FILE_CHECK;
+ else if (strcmp(args[0].from, "MODULE_CHECK") == 0)
+ entry->func = MODULE_CHECK;
+ else if (strcmp(args[0].from, "FIRMWARE_CHECK") == 0)
+ entry->func = FIRMWARE_CHECK;
+ else if ((strcmp(args[0].from, "FILE_MMAP") == 0)
+ || (strcmp(args[0].from, "MMAP_CHECK") == 0))
+ entry->func = MMAP_CHECK;
+ else if (strcmp(args[0].from, "BPRM_CHECK") == 0)
+ entry->func = BPRM_CHECK;
+ else
+ result = -EINVAL;
+ if (!result)
+ entry->flags |= IMA_FUNC;
+ break;
+ case Opt_mask:
+ ima_log_string(ab, "mask", args[0].from);
+
+ if (entry->mask)
+ result = -EINVAL;
+
+ from = args[0].from;
+ if (*from == '^')
+ from++;
+
+ if ((strcmp(from, "MAY_EXEC")) == 0)
+ entry->mask = MAY_EXEC;
+ else if (strcmp(from, "MAY_WRITE") == 0)
+ entry->mask = MAY_WRITE;
+ else if (strcmp(from, "MAY_READ") == 0)
+ entry->mask = MAY_READ;
+ else if (strcmp(from, "MAY_APPEND") == 0)
+ entry->mask = MAY_APPEND;
+ else
+ result = -EINVAL;
+ if (!result)
+ entry->flags |= (*args[0].from == '^')
+ ? IMA_INMASK : IMA_MASK;
+ break;
+ case Opt_fsmagic:
+ ima_log_string(ab, "fsmagic", args[0].from);
+
+ if (entry->fsmagic) {
+ result = -EINVAL;
+ break;
+ }
+
+ result = kstrtoul(args[0].from, 16, &entry->fsmagic);
+ if (!result)
+ entry->flags |= IMA_FSMAGIC;
+ break;
+ case Opt_fsuuid:
+ ima_log_string(ab, "fsuuid", args[0].from);
+
+ if (memchr_inv(entry->fsuuid, 0x00,
+ sizeof(entry->fsuuid))) {
+ result = -EINVAL;
+ break;
+ }
+
+ result = blk_part_pack_uuid(args[0].from,
+ entry->fsuuid);
+ if (!result)
+ entry->flags |= IMA_FSUUID;
+ break;
+ case Opt_uid:
+ ima_log_string(ab, "uid", args[0].from);
+ case Opt_euid:
+ if (token == Opt_euid)
+ ima_log_string(ab, "euid", args[0].from);
+
+ if (uid_valid(entry->uid)) {
+ result = -EINVAL;
+ break;
+ }
+
+ result = kstrtoul(args[0].from, 10, &lnum);
+ if (!result) {
+ entry->uid = make_kuid(current_user_ns(),
+ (uid_t) lnum);
+ if (!uid_valid(entry->uid) ||
+ (uid_t)lnum != lnum)
+ result = -EINVAL;
+ else
+ entry->flags |= (token == Opt_uid)
+ ? IMA_UID : IMA_EUID;
+ }
+ break;
+ case Opt_fowner:
+ ima_log_string(ab, "fowner", args[0].from);
+
+ if (uid_valid(entry->fowner)) {
+ result = -EINVAL;
+ break;
+ }
+
+ result = kstrtoul(args[0].from, 10, &lnum);
+ if (!result) {
+ entry->fowner = make_kuid(current_user_ns(), (uid_t)lnum);
+ if (!uid_valid(entry->fowner) || (((uid_t)lnum) != lnum))
+ result = -EINVAL;
+ else
+ entry->flags |= IMA_FOWNER;
+ }
+ break;
+ case Opt_obj_user:
+ ima_log_string(ab, "obj_user", args[0].from);
+ result = ima_lsm_rule_init(entry, args,
+ LSM_OBJ_USER,
+ AUDIT_OBJ_USER);
+ break;
+ case Opt_obj_role:
+ ima_log_string(ab, "obj_role", args[0].from);
+ result = ima_lsm_rule_init(entry, args,
+ LSM_OBJ_ROLE,
+ AUDIT_OBJ_ROLE);
+ break;
+ case Opt_obj_type:
+ ima_log_string(ab, "obj_type", args[0].from);
+ result = ima_lsm_rule_init(entry, args,
+ LSM_OBJ_TYPE,
+ AUDIT_OBJ_TYPE);
+ break;
+ case Opt_subj_user:
+ ima_log_string(ab, "subj_user", args[0].from);
+ result = ima_lsm_rule_init(entry, args,
+ LSM_SUBJ_USER,
+ AUDIT_SUBJ_USER);
+ break;
+ case Opt_subj_role:
+ ima_log_string(ab, "subj_role", args[0].from);
+ result = ima_lsm_rule_init(entry, args,
+ LSM_SUBJ_ROLE,
+ AUDIT_SUBJ_ROLE);
+ break;
+ case Opt_subj_type:
+ ima_log_string(ab, "subj_type", args[0].from);
+ result = ima_lsm_rule_init(entry, args,
+ LSM_SUBJ_TYPE,
+ AUDIT_SUBJ_TYPE);
+ break;
+ case Opt_appraise_type:
+ if (entry->action != APPRAISE) {
+ result = -EINVAL;
+ break;
+ }
+
+ ima_log_string(ab, "appraise_type", args[0].from);
+ if ((strcmp(args[0].from, "imasig")) == 0)
+ entry->flags |= IMA_DIGSIG_REQUIRED;
+ else
+ result = -EINVAL;
+ break;
+ case Opt_permit_directio:
+ entry->flags |= IMA_PERMIT_DIRECTIO;
+ break;
+ case Opt_err:
+ ima_log_string(ab, "UNKNOWN", p);
+ result = -EINVAL;
+ break;
+ }
+ }
+ if (!result && (entry->action == UNKNOWN))
+ result = -EINVAL;
+ else if (entry->func == MODULE_CHECK)
+ ima_appraise |= IMA_APPRAISE_MODULES;
+ else if (entry->func == FIRMWARE_CHECK)
+ ima_appraise |= IMA_APPRAISE_FIRMWARE;
+ audit_log_format(ab, "res=%d", !result);
+ audit_log_end(ab);
+ return result;
+}
+
+/**
+ * ima_parse_add_rule - add a rule to ima_policy_rules
+ * @rule - ima measurement policy rule
+ *
+ * Uses a mutex to protect the policy list from multiple concurrent writers.
+ * Returns the length of the rule parsed, an error code on failure
+ */
+ssize_t ima_parse_add_rule(char *rule)
+{
+ static const char op[] = "update_policy";
+ char *p;
+ struct ima_rule_entry *entry;
+ ssize_t result, len;
+ int audit_info = 0;
+
+ p = strsep(&rule, "\n");
+ len = strlen(p) + 1;
+ p += strspn(p, " \t");
+
+ if (*p == '#' || *p == '\0')
+ return len;
+
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry) {
+ integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
+ NULL, op, "-ENOMEM", -ENOMEM, audit_info);
+ return -ENOMEM;
+ }
+
+ INIT_LIST_HEAD(&entry->list);
+
+ result = ima_parse_rule(p, entry);
+ if (result) {
+ kfree(entry);
+ integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
+ NULL, op, "invalid-policy", result,
+ audit_info);
+ return result;
+ }
+
+ mutex_lock(&ima_rules_mutex);
+ list_add_tail(&entry->list, &ima_policy_rules);
+ mutex_unlock(&ima_rules_mutex);
+
+ return len;
+}
+
+/* ima_delete_rules called to cleanup invalid policy */
+void ima_delete_rules(void)
+{
+ struct ima_rule_entry *entry, *tmp;
+ int i;
+
+ mutex_lock(&ima_rules_mutex);
+ list_for_each_entry_safe(entry, tmp, &ima_policy_rules, list) {
+ for (i = 0; i < MAX_LSM_RULES; i++)
+ kfree(entry->lsm[i].args_p);
+
+ list_del(&entry->list);
+ kfree(entry);
+ }
+ mutex_unlock(&ima_rules_mutex);
+}