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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (C) 2008 IBM Corporation
  * Author: Mimi Zohar <zohar@us.ibm.com>
  *
  * ima_policy.c
  *  - initialize default measure policy rules
  */
 
 #include <linux/init.h>
 #include <linux/list.h>
 #include <linux/kernel_read_file.h>
 #include <linux/fs.h>
 #include <linux/security.h>
 #include <linux/magic.h>
 #include <linux/parser.h>
 #include <linux/slab.h>
 #include <linux/rculist.h>
 #include <linux/seq_file.h>
 #include <linux/ima.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 IMA_PCR     0x0100
 #define IMA_FSNAME  0x0200
 #define IMA_KEYRINGS    0x0400
 #define IMA_LABEL   0x0800
 #define IMA_VALIDATE_ALGOS  0x1000
 #define IMA_GID     0x2000
 #define IMA_EGID    0x4000
 #define IMA_FGROUP  0x8000
 
 #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
 #define HASH        0x0100
 #define DONT_HASH   0x0200
 
 #define INVALID_PCR(a) (((a) < 0) || \
     (a) >= (sizeof_field(struct integrity_iint_cache, measured_pcrs) * 8))
 
 int ima_policy_flag;
 static int temp_ima_appraise;
 static int build_ima_appraise __ro_after_init;
 
 atomic_t ima_setxattr_allowed_hash_algorithms;
 
 #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 };
 
 enum policy_rule_list { IMA_DEFAULT_POLICY = 1, IMA_CUSTOM_POLICY };
 
 struct ima_rule_opt_list {
     size_t count;
     char *items[];
 };
 
 struct ima_rule_entry {
     struct list_head list;
     int action;
     unsigned int flags;
     enum ima_hooks func;
     int mask;
     unsigned long fsmagic;
     uuid_t fsuuid;
     kuid_t uid;
     kgid_t gid;
     kuid_t fowner;
     kgid_t fgroup;
     bool (*uid_op)(kuid_t cred_uid, kuid_t rule_uid);    /* Handlers for operators       */
     bool (*gid_op)(kgid_t cred_gid, kgid_t rule_gid);
     bool (*fowner_op)(kuid_t cred_uid, kuid_t rule_uid); /* uid_eq(), uid_gt(), uid_lt() */
     bool (*fgroup_op)(kgid_t cred_gid, kgid_t rule_gid); /* gid_eq(), gid_gt(), gid_lt() */
     int pcr;
     unsigned int allowed_algos; /* bitfield of allowed hash algorithms */
     struct {
         void *rule; /* LSM file metadata specific */
         char *args_p;   /* audit value */
         int type;   /* audit type */
     } lsm[MAX_LSM_RULES];
     char *fsname;
     struct ima_rule_opt_list *keyrings; /* Measure keys added to these keyrings */
     struct ima_rule_opt_list *label; /* Measure data grouped under this label */
     struct ima_template_desc *template;
 };
 
 /*
  * sanity check in case the kernels gains more hash algorithms that can
  * fit in an unsigned int
  */
 static_assert(
     8 * sizeof(unsigned int) >= HASH_ALGO__LAST,
     "The bitfield allowed_algos in ima_rule_entry is too small to contain all the supported hash algorithms, consider using a bigger type");
 
 /*
  * Without LSM specific knowledge, the default policy can only be
  * written in terms of .action, .func, .mask, .fsmagic, .uid, .gid,
  * .fowner, and .fgroup
  */
 
 /*
  * 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[] __ro_after_init = {
     {.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 = SMACK_MAGIC, .flags = IMA_FSMAGIC},
     {.action = DONT_MEASURE, .fsmagic = CGROUP_SUPER_MAGIC,
      .flags = IMA_FSMAGIC},
     {.action = DONT_MEASURE, .fsmagic = CGROUP2_SUPER_MAGIC,
      .flags = IMA_FSMAGIC},
     {.action = DONT_MEASURE, .fsmagic = NSFS_MAGIC, .flags = IMA_FSMAGIC},
     {.action = DONT_MEASURE, .fsmagic = EFIVARFS_MAGIC, .flags = IMA_FSMAGIC}
 };
 
 static struct ima_rule_entry original_measurement_rules[] __ro_after_init = {
     {.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, .uid_op = &uid_eq,
      .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[] __ro_after_init = {
     {.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, .uid_op = &uid_eq,
      .flags = IMA_FUNC | IMA_INMASK | IMA_EUID},
     {.action = MEASURE, .func = FILE_CHECK, .mask = MAY_READ,
      .uid = GLOBAL_ROOT_UID, .uid_op = &uid_eq,
      .flags = IMA_FUNC | IMA_INMASK | IMA_UID},
     {.action = MEASURE, .func = MODULE_CHECK, .flags = IMA_FUNC},
     {.action = MEASURE, .func = FIRMWARE_CHECK, .flags = IMA_FUNC},
     {.action = MEASURE, .func = POLICY_CHECK, .flags = IMA_FUNC},
 };
 
 static struct ima_rule_entry default_appraise_rules[] __ro_after_init = {
     {.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 = SMACK_MAGIC, .flags = IMA_FSMAGIC},
     {.action = DONT_APPRAISE, .fsmagic = NSFS_MAGIC, .flags = IMA_FSMAGIC},
     {.action = DONT_APPRAISE, .fsmagic = EFIVARFS_MAGIC, .flags = IMA_FSMAGIC},
     {.action = DONT_APPRAISE, .fsmagic = CGROUP_SUPER_MAGIC, .flags = IMA_FSMAGIC},
     {.action = DONT_APPRAISE, .fsmagic = CGROUP2_SUPER_MAGIC, .flags = IMA_FSMAGIC},
 #ifdef CONFIG_IMA_WRITE_POLICY
     {.action = APPRAISE, .func = POLICY_CHECK,
     .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
 #endif
 #ifndef CONFIG_IMA_APPRAISE_SIGNED_INIT
     {.action = APPRAISE, .fowner = GLOBAL_ROOT_UID, .fowner_op = &uid_eq,
      .flags = IMA_FOWNER},
 #else
     /* force signature */
     {.action = APPRAISE, .fowner = GLOBAL_ROOT_UID, .fowner_op = &uid_eq,
      .flags = IMA_FOWNER | IMA_DIGSIG_REQUIRED},
 #endif
 };
 
 static struct ima_rule_entry build_appraise_rules[] __ro_after_init = {
 #ifdef CONFIG_IMA_APPRAISE_REQUIRE_MODULE_SIGS
     {.action = APPRAISE, .func = MODULE_CHECK,
      .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
 #endif
 #ifdef CONFIG_IMA_APPRAISE_REQUIRE_FIRMWARE_SIGS
     {.action = APPRAISE, .func = FIRMWARE_CHECK,
      .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
 #endif
 #ifdef CONFIG_IMA_APPRAISE_REQUIRE_KEXEC_SIGS
     {.action = APPRAISE, .func = KEXEC_KERNEL_CHECK,
      .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
 #endif
 #ifdef CONFIG_IMA_APPRAISE_REQUIRE_POLICY_SIGS
     {.action = APPRAISE, .func = POLICY_CHECK,
      .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
 #endif
 };
 
 static struct ima_rule_entry secure_boot_rules[] __ro_after_init = {
     {.action = APPRAISE, .func = MODULE_CHECK,
      .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
     {.action = APPRAISE, .func = FIRMWARE_CHECK,
      .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
     {.action = APPRAISE, .func = KEXEC_KERNEL_CHECK,
      .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
     {.action = APPRAISE, .func = POLICY_CHECK,
      .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
 };
 
 static struct ima_rule_entry critical_data_rules[] __ro_after_init = {
     {.action = MEASURE, .func = CRITICAL_DATA, .flags = IMA_FUNC},
 };
 
 /* An array of architecture specific rules */
 static struct ima_rule_entry *arch_policy_entry __ro_after_init;
 
 static LIST_HEAD(ima_default_rules);
 static LIST_HEAD(ima_policy_rules);
 static LIST_HEAD(ima_temp_rules);
 static struct list_head __rcu *ima_rules = (struct list_head __rcu *)(&ima_default_rules);
 
 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 bool ima_use_appraise_tcb __initdata;
 static bool ima_use_secure_boot __initdata;
 static bool ima_use_critical_data __initdata;
 static bool ima_fail_unverifiable_sigs __ro_after_init;
 static int __init policy_setup(char *str)
 {
     char *p;
 
     while ((p = strsep(&str, " |\n")) != NULL) {
         if (*p == ' ')
             continue;
         if ((strcmp(p, "tcb") == 0) && !ima_policy)
             ima_policy = DEFAULT_TCB;
         else if (strcmp(p, "appraise_tcb") == 0)
             ima_use_appraise_tcb = true;
         else if (strcmp(p, "secure_boot") == 0)
             ima_use_secure_boot = true;
         else if (strcmp(p, "critical_data") == 0)
             ima_use_critical_data = true;
         else if (strcmp(p, "fail_securely") == 0)
             ima_fail_unverifiable_sigs = true;
         else
             pr_err("policy \"%s\" not found", p);
     }
 
     return 1;
 }
 __setup("ima_policy=", policy_setup);
 
 static int __init default_appraise_policy_setup(char *str)
 {
     ima_use_appraise_tcb = true;
     return 1;
 }
 __setup("ima_appraise_tcb", default_appraise_policy_setup);
 
 static struct ima_rule_opt_list *ima_alloc_rule_opt_list(const substring_t *src)
 {
     struct ima_rule_opt_list *opt_list;
     size_t count = 0;
     char *src_copy;
     char *cur, *next;
     size_t i;
 
     src_copy = match_strdup(src);
     if (!src_copy)
         return ERR_PTR(-ENOMEM);
 
     next = src_copy;
     while ((cur = strsep(&next, "|"))) {
         /* Don't accept an empty list item */
         if (!(*cur)) {
             kfree(src_copy);
             return ERR_PTR(-EINVAL);
         }
         count++;
     }
 
     /* Don't accept an empty list */
     if (!count) {
         kfree(src_copy);
         return ERR_PTR(-EINVAL);
     }
 
     opt_list = kzalloc(struct_size(opt_list, items, count), GFP_KERNEL);
     if (!opt_list) {
         kfree(src_copy);
         return ERR_PTR(-ENOMEM);
     }
 
     /*
      * strsep() has already replaced all instances of '|' with '\0',
      * leaving a byte sequence of NUL-terminated strings. Reference each
      * string with the array of items.
      *
      * IMPORTANT: Ownership of the allocated buffer is transferred from
      * src_copy to the first element in the items array. To free the
      * buffer, kfree() must only be called on the first element of the
      * array.
      */
     for (i = 0, cur = src_copy; i < count; i++) {
         opt_list->items[i] = cur;
         cur = strchr(cur, '\0') + 1;
     }
     opt_list->count = count;
 
     return opt_list;
 }
 
 static void ima_free_rule_opt_list(struct ima_rule_opt_list *opt_list)
 {
     if (!opt_list)
         return;
 
     if (opt_list->count) {
         kfree(opt_list->items[0]);
         opt_list->count = 0;
     }
 
     kfree(opt_list);
 }
 
 static void ima_lsm_free_rule(struct ima_rule_entry *entry)
 {
     int i;
 
     for (i = 0; i < MAX_LSM_RULES; i++) {
         ima_filter_rule_free(entry->lsm[i].rule);
         kfree(entry->lsm[i].args_p);
     }
 }
 
 static void ima_free_rule(struct ima_rule_entry *entry)
 {
     if (!entry)
         return;
 
     /*
      * entry->template->fields may be allocated in ima_parse_rule() but that
      * reference is owned by the corresponding ima_template_desc element in
      * the defined_templates list and cannot be freed here
      */
     kfree(entry->fsname);
     ima_free_rule_opt_list(entry->keyrings);
     ima_lsm_free_rule(entry);
     kfree(entry);
 }
 
 static struct ima_rule_entry *ima_lsm_copy_rule(struct ima_rule_entry *entry)
 {
     struct ima_rule_entry *nentry;
     int i;
 
     /*
      * Immutable elements are copied over as pointers and data; only
      * lsm rules can change
      */
     nentry = kmemdup(entry, sizeof(*nentry), GFP_KERNEL);
     if (!nentry)
         return NULL;
 
     memset(nentry->lsm, 0, sizeof_field(struct ima_rule_entry, lsm));
 
     for (i = 0; i < MAX_LSM_RULES; i++) {
         if (!entry->lsm[i].args_p)
             continue;
 
         nentry->lsm[i].type = entry->lsm[i].type;
         nentry->lsm[i].args_p = entry->lsm[i].args_p;
         /*
          * Remove the reference from entry so that the associated
          * memory will not be freed during a later call to
          * ima_lsm_free_rule(entry).
          */
         entry->lsm[i].args_p = NULL;
 
         ima_filter_rule_init(nentry->lsm[i].type, Audit_equal,
                      nentry->lsm[i].args_p,
                      &nentry->lsm[i].rule);
         if (!nentry->lsm[i].rule)
             pr_warn("rule for LSM \'%s\' is undefined\n",
                 nentry->lsm[i].args_p);
     }
     return nentry;
 }
 
 static int ima_lsm_update_rule(struct ima_rule_entry *entry)
 {
     struct ima_rule_entry *nentry;
 
     nentry = ima_lsm_copy_rule(entry);
     if (!nentry)
         return -ENOMEM;
 
     list_replace_rcu(&entry->list, &nentry->list);
     synchronize_rcu();
     /*
      * ima_lsm_copy_rule() shallow copied all references, except for the
      * LSM references, from entry to nentry so we only want to free the LSM
      * references and the entry itself. All other memory references will now
      * be owned by nentry.
      */
     ima_lsm_free_rule(entry);
     kfree(entry);
 
     return 0;
 }
 
 static bool ima_rule_contains_lsm_cond(struct ima_rule_entry *entry)
 {
     int i;
 
     for (i = 0; i < MAX_LSM_RULES; i++)
         if (entry->lsm[i].args_p)
             return true;
 
     return false;
 }
 
 /*
  * 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.
  */
 static void ima_lsm_update_rules(void)
 {
     struct ima_rule_entry *entry, *e;
     int result;
 
     list_for_each_entry_safe(entry, e, &ima_policy_rules, list) {
         if (!ima_rule_contains_lsm_cond(entry))
             continue;
 
         result = ima_lsm_update_rule(entry);
         if (result) {
             pr_err("lsm rule update error %d\n", result);
             return;
         }
     }
 }
 
 int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event,
               void *lsm_data)
 {
     if (event != LSM_POLICY_CHANGE)
         return NOTIFY_DONE;
 
     ima_lsm_update_rules();
     return NOTIFY_OK;
 }
 
 /**
  * ima_match_rule_data - determine whether func_data matches the policy rule
  * @rule: a pointer to a rule
  * @func_data: data to match against the measure rule data
  * @cred: a pointer to a credentials structure for user validation
  *
  * Returns true if func_data matches one in the rule, false otherwise.
  */
 static bool ima_match_rule_data(struct ima_rule_entry *rule,
                 const char *func_data,
                 const struct cred *cred)
 {
     const struct ima_rule_opt_list *opt_list = NULL;
     bool matched = false;
     size_t i;
 
     if ((rule->flags & IMA_UID) && !rule->uid_op(cred->uid, rule->uid))
         return false;
 
     switch (rule->func) {
     case KEY_CHECK:
         if (!rule->keyrings)
             return true;
 
         opt_list = rule->keyrings;
         break;
     case CRITICAL_DATA:
         if (!rule->label)
             return true;
 
         opt_list = rule->label;
         break;
     default:
         return false;
     }
 
     if (!func_data)
         return false;
 
     for (i = 0; i < opt_list->count; i++) {
         if (!strcmp(opt_list->items[i], func_data)) {
             matched = true;
             break;
         }
     }
 
     return matched;
 }
 
 /**
  * ima_match_rules - determine whether an inode matches the policy rule.
  * @rule: a pointer to a rule
  * @mnt_userns: user namespace of the mount the inode was found from
  * @inode: a pointer to an inode
  * @cred: a pointer to a credentials structure for user validation
  * @secid: the secid of the task to be validated
  * @func: LIM hook identifier
  * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
  * @func_data: func specific data, may be NULL
  *
  * Returns true on rule match, false on failure.
  */
 static bool ima_match_rules(struct ima_rule_entry *rule,
                 struct user_namespace *mnt_userns,
                 struct inode *inode, const struct cred *cred,
                 u32 secid, enum ima_hooks func, int mask,
                 const char *func_data)
 {
     int i;
 
     if ((rule->flags & IMA_FUNC) &&
         (rule->func != func && func != POST_SETATTR))
         return false;
 
     switch (func) {
     case KEY_CHECK:
     case CRITICAL_DATA:
         return ((rule->func == func) &&
             ima_match_rule_data(rule, func_data, cred));
     default:
         break;
     }
 
     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_FSNAME)
         && strcmp(rule->fsname, inode->i_sb->s_type->name))
         return false;
     if ((rule->flags & IMA_FSUUID) &&
         !uuid_equal(&rule->fsuuid, &inode->i_sb->s_uuid))
         return false;
     if ((rule->flags & IMA_UID) && !rule->uid_op(cred->uid, rule->uid))
         return false;
     if (rule->flags & IMA_EUID) {
         if (has_capability_noaudit(current, CAP_SETUID)) {
             if (!rule->uid_op(cred->euid, rule->uid)
                 && !rule->uid_op(cred->suid, rule->uid)
                 && !rule->uid_op(cred->uid, rule->uid))
                 return false;
         } else if (!rule->uid_op(cred->euid, rule->uid))
             return false;
     }
     if ((rule->flags & IMA_GID) && !rule->gid_op(cred->gid, rule->gid))
         return false;
     if (rule->flags & IMA_EGID) {
         if (has_capability_noaudit(current, CAP_SETGID)) {
             if (!rule->gid_op(cred->egid, rule->gid)
                 && !rule->gid_op(cred->sgid, rule->gid)
                 && !rule->gid_op(cred->gid, rule->gid))
                 return false;
         } else if (!rule->gid_op(cred->egid, rule->gid))
             return false;
     }
     if ((rule->flags & IMA_FOWNER) &&
         !rule->fowner_op(i_uid_into_mnt(mnt_userns, inode), rule->fowner))
         return false;
     if ((rule->flags & IMA_FGROUP) &&
         !rule->fgroup_op(i_gid_into_mnt(mnt_userns, inode), rule->fgroup))
         return false;
     for (i = 0; i < MAX_LSM_RULES; i++) {
         int rc = 0;
         u32 osid;
 
         if (!rule->lsm[i].rule) {
             if (!rule->lsm[i].args_p)
                 continue;
             else
                 return false;
         }
         switch (i) {
         case LSM_OBJ_USER:
         case LSM_OBJ_ROLE:
         case LSM_OBJ_TYPE:
             security_inode_getsecid(inode, &osid);
             rc = ima_filter_rule_match(osid, rule->lsm[i].type,
                            Audit_equal,
                            rule->lsm[i].rule);
             break;
         case LSM_SUBJ_USER:
         case LSM_SUBJ_ROLE:
         case LSM_SUBJ_TYPE:
             rc = ima_filter_rule_match(secid, rule->lsm[i].type,
                            Audit_equal,
                            rule->lsm[i].rule);
             break;
         default:
             break;
         }
         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, enum ima_hooks 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 CREDS_CHECK:
         return IMA_CREDS_APPRAISE;
     case FILE_CHECK:
     case POST_SETATTR:
         return IMA_FILE_APPRAISE;
     case MODULE_CHECK ... MAX_CHECK - 1:
     default:
         return IMA_READ_APPRAISE;
     }
 }
 
 /**
  * ima_match_policy - decision based on LSM and other conditions
  * @mnt_userns: user namespace of the mount the inode was found from
  * @inode: pointer to an inode for which the policy decision is being made
  * @cred: pointer to a credentials structure for which the policy decision is
  *        being made
  * @secid: LSM secid of the task to be validated
  * @func: IMA hook identifier
  * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
  * @pcr: set the pcr to extend
  * @template_desc: the template that should be used for this rule
  * @func_data: func specific data, may be NULL
  * @allowed_algos: allowlist of hash algorithms for the IMA xattr
  *
  * Measure decision based on func/mask/fsmagic and LSM(subj/obj/type)
  * conditions.
  *
  * Since the IMA policy may be updated multiple times we need to lock the
  * list when walking it.  Reads are many orders of magnitude more numerous
  * than writes so ima_match_policy() is classical RCU candidate.
  */
 int ima_match_policy(struct user_namespace *mnt_userns, struct inode *inode,
              const struct cred *cred, u32 secid, enum ima_hooks func,
              int mask, int flags, int *pcr,
              struct ima_template_desc **template_desc,
              const char *func_data, unsigned int *allowed_algos)
 {
     struct ima_rule_entry *entry;
     int action = 0, actmask = flags | (flags << 1);
     struct list_head *ima_rules_tmp;
 
     if (template_desc && !*template_desc)
         *template_desc = ima_template_desc_current();
 
     rcu_read_lock();
     ima_rules_tmp = rcu_dereference(ima_rules);
     list_for_each_entry_rcu(entry, ima_rules_tmp, list) {
 
         if (!(entry->action & actmask))
             continue;
 
         if (!ima_match_rules(entry, mnt_userns, inode, cred, secid,
                      func, mask, func_data))
             continue;
 
         action |= entry->flags & IMA_NONACTION_FLAGS;
 
         action |= entry->action & IMA_DO_MASK;
         if (entry->action & IMA_APPRAISE) {
             action |= get_subaction(entry, func);
             action &= ~IMA_HASH;
             if (ima_fail_unverifiable_sigs)
                 action |= IMA_FAIL_UNVERIFIABLE_SIGS;
 
             if (allowed_algos &&
                 entry->flags & IMA_VALIDATE_ALGOS)
                 *allowed_algos = entry->allowed_algos;
         }
 
         if (entry->action & IMA_DO_MASK)
             actmask &= ~(entry->action | entry->action << 1);
         else
             actmask &= ~(entry->action | entry->action >> 1);
 
         if ((pcr) && (entry->flags & IMA_PCR))
             *pcr = entry->pcr;
 
         if (template_desc && entry->template)
             *template_desc = entry->template;
 
         if (!actmask)
             break;
     }
     rcu_read_unlock();
 
     return action;
 }
 
 /**
  * ima_update_policy_flags() - Update global IMA variables
  *
  * Update ima_policy_flag and ima_setxattr_allowed_hash_algorithms
  * based on the currently loaded policy.
  *
  * With ima_policy_flag, the decision to short circuit out of a function
  * or not call the function in the first place can be made earlier.
  *
  * With ima_setxattr_allowed_hash_algorithms, the policy can restrict the
  * set of hash algorithms accepted when updating the security.ima xattr of
  * a file.
  *
  * Context: called after a policy update and at system initialization.
  */
 void ima_update_policy_flags(void)
 {
     struct ima_rule_entry *entry;
     int new_policy_flag = 0;
     struct list_head *ima_rules_tmp;
 
     rcu_read_lock();
     ima_rules_tmp = rcu_dereference(ima_rules);
     list_for_each_entry_rcu(entry, ima_rules_tmp, list) {
         /*
          * SETXATTR_CHECK rules do not implement a full policy check
          * because rule checking would probably have an important
          * performance impact on setxattr(). As a consequence, only one
          * SETXATTR_CHECK can be active at a given time.
          * Because we want to preserve that property, we set out to use
          * atomic_cmpxchg. Either:
          * - the atomic was non-zero: a setxattr hash policy is
          *   already enforced, we do nothing
          * - the atomic was zero: no setxattr policy was set, enable
          *   the setxattr hash policy
          */
         if (entry->func == SETXATTR_CHECK) {
             atomic_cmpxchg(&ima_setxattr_allowed_hash_algorithms,
                        0, entry->allowed_algos);
             /* SETXATTR_CHECK doesn't impact ima_policy_flag */
             continue;
         }
 
         if (entry->action & IMA_DO_MASK)
             new_policy_flag |= entry->action;
     }
     rcu_read_unlock();
 
     ima_appraise |= (build_ima_appraise | temp_ima_appraise);
     if (!ima_appraise)
         new_policy_flag &= ~IMA_APPRAISE;
 
     ima_policy_flag = new_policy_flag;
 }
 
 static int ima_appraise_flag(enum ima_hooks func)
 {
     if (func == MODULE_CHECK)
         return IMA_APPRAISE_MODULES;
     else if (func == FIRMWARE_CHECK)
         return IMA_APPRAISE_FIRMWARE;
     else if (func == POLICY_CHECK)
         return IMA_APPRAISE_POLICY;
     else if (func == KEXEC_KERNEL_CHECK)
         return IMA_APPRAISE_KEXEC;
     return 0;
 }
 
 static void add_rules(struct ima_rule_entry *entries, int count,
               enum policy_rule_list policy_rule)
 {
     int i = 0;
 
     for (i = 0; i < count; i++) {
         struct ima_rule_entry *entry;
 
         if (policy_rule & IMA_DEFAULT_POLICY)
             list_add_tail(&entries[i].list, &ima_default_rules);
 
         if (policy_rule & IMA_CUSTOM_POLICY) {
             entry = kmemdup(&entries[i], sizeof(*entry),
                     GFP_KERNEL);
             if (!entry)
                 continue;
 
             list_add_tail(&entry->list, &ima_policy_rules);
         }
         if (entries[i].action == APPRAISE) {
             if (entries != build_appraise_rules)
                 temp_ima_appraise |=
                     ima_appraise_flag(entries[i].func);
             else
                 build_ima_appraise |=
                     ima_appraise_flag(entries[i].func);
         }
     }
 }
 
 static int ima_parse_rule(char *rule, struct ima_rule_entry *entry);
 
 static int __init ima_init_arch_policy(void)
 {
     const char * const *arch_rules;
     const char * const *rules;
     int arch_entries = 0;
     int i = 0;
 
     arch_rules = arch_get_ima_policy();
     if (!arch_rules)
         return arch_entries;
 
     /* Get number of rules */
     for (rules = arch_rules; *rules != NULL; rules++)
         arch_entries++;
 
     arch_policy_entry = kcalloc(arch_entries + 1,
                     sizeof(*arch_policy_entry), GFP_KERNEL);
     if (!arch_policy_entry)
         return 0;
 
     /* Convert each policy string rules to struct ima_rule_entry format */
     for (rules = arch_rules, i = 0; *rules != NULL; rules++) {
         char rule[255];
         int result;
 
         result = strscpy(rule, *rules, sizeof(rule));
 
         INIT_LIST_HEAD(&arch_policy_entry[i].list);
         result = ima_parse_rule(rule, &arch_policy_entry[i]);
         if (result) {
             pr_warn("Skipping unknown architecture policy rule: %s\n",
                 rule);
             memset(&arch_policy_entry[i], 0,
                    sizeof(*arch_policy_entry));
             continue;
         }
         i++;
     }
     return i;
 }
 
 /**
  * ima_init_policy - initialize the default measure rules.
  *
  * ima_rules points to either the ima_default_rules or the new ima_policy_rules.
  */
 void __init ima_init_policy(void)
 {
     int build_appraise_entries, arch_entries;
 
     /* if !ima_policy, we load NO default rules */
     if (ima_policy)
         add_rules(dont_measure_rules, ARRAY_SIZE(dont_measure_rules),
               IMA_DEFAULT_POLICY);
 
     switch (ima_policy) {
     case ORIGINAL_TCB:
         add_rules(original_measurement_rules,
               ARRAY_SIZE(original_measurement_rules),
               IMA_DEFAULT_POLICY);
         break;
     case DEFAULT_TCB:
         add_rules(default_measurement_rules,
               ARRAY_SIZE(default_measurement_rules),
               IMA_DEFAULT_POLICY);
         break;
     default:
         break;
     }
 
     /*
      * Based on runtime secure boot flags, insert arch specific measurement
      * and appraise rules requiring file signatures for both the initial
      * and custom policies, prior to other appraise rules.
      * (Highest priority)
      */
     arch_entries = ima_init_arch_policy();
     if (!arch_entries)
         pr_info("No architecture policies found\n");
     else
         add_rules(arch_policy_entry, arch_entries,
               IMA_DEFAULT_POLICY | IMA_CUSTOM_POLICY);
 
     /*
      * Insert the builtin "secure_boot" policy rules requiring file
      * signatures, prior to other appraise rules.
      */
     if (ima_use_secure_boot)
         add_rules(secure_boot_rules, ARRAY_SIZE(secure_boot_rules),
               IMA_DEFAULT_POLICY);
 
     /*
      * Insert the build time appraise rules requiring file signatures
      * for both the initial and custom policies, prior to other appraise
      * rules. As the secure boot rules includes all of the build time
      * rules, include either one or the other set of rules, but not both.
      */
     build_appraise_entries = ARRAY_SIZE(build_appraise_rules);
     if (build_appraise_entries) {
         if (ima_use_secure_boot)
             add_rules(build_appraise_rules, build_appraise_entries,
                   IMA_CUSTOM_POLICY);
         else
             add_rules(build_appraise_rules, build_appraise_entries,
                   IMA_DEFAULT_POLICY | IMA_CUSTOM_POLICY);
     }
 
     if (ima_use_appraise_tcb)
         add_rules(default_appraise_rules,
               ARRAY_SIZE(default_appraise_rules),
               IMA_DEFAULT_POLICY);
 
     if (ima_use_critical_data)
         add_rules(critical_data_rules,
               ARRAY_SIZE(critical_data_rules),
               IMA_DEFAULT_POLICY);
 
     atomic_set(&ima_setxattr_allowed_hash_algorithms, 0);
 
     ima_update_policy_flags();
 }
 
 /* Make sure we have a valid policy, at least containing some rules. */
 int ima_check_policy(void)
 {
     if (list_empty(&ima_temp_rules))
         return -EINVAL;
     return 0;
 }
 
 /**
  * ima_update_policy - update default_rules with new measure rules
  *
  * Called on file .release to update the default rules with a complete new
  * policy.  What we do here is to splice ima_policy_rules and ima_temp_rules so
  * they make a queue.  The policy may be updated multiple times and this is the
  * RCU updater.
  *
  * Policy rules are never deleted so ima_policy_flag gets zeroed only once when
  * we switch from the default policy to user defined.
  */
 void ima_update_policy(void)
 {
     struct list_head *policy = &ima_policy_rules;
 
     list_splice_tail_init_rcu(&ima_temp_rules, policy, synchronize_rcu);
 
     if (ima_rules != (struct list_head __rcu *)policy) {
         ima_policy_flag = 0;
 
         rcu_assign_pointer(ima_rules, policy);
         /*
          * IMA architecture specific policy rules are specified
          * as strings and converted to an array of ima_entry_rules
          * on boot.  After loading a custom policy, free the
          * architecture specific rules stored as an array.
          */
         kfree(arch_policy_entry);
     }
     ima_update_policy_flags();
 
     /* Custom IMA policy has been loaded */
     ima_process_queued_keys();
 }
 
 /* Keep the enumeration in sync with the policy_tokens! */
 enum policy_opt {
     Opt_measure, Opt_dont_measure,
     Opt_appraise, Opt_dont_appraise,
     Opt_audit, Opt_hash, Opt_dont_hash,
     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_fsname, Opt_fsuuid,
     Opt_uid_eq, Opt_euid_eq, Opt_gid_eq, Opt_egid_eq,
     Opt_fowner_eq, Opt_fgroup_eq,
     Opt_uid_gt, Opt_euid_gt, Opt_gid_gt, Opt_egid_gt,
     Opt_fowner_gt, Opt_fgroup_gt,
     Opt_uid_lt, Opt_euid_lt, Opt_gid_lt, Opt_egid_lt,
     Opt_fowner_lt, Opt_fgroup_lt,
     Opt_digest_type,
     Opt_appraise_type, Opt_appraise_flag, Opt_appraise_algos,
     Opt_permit_directio, Opt_pcr, Opt_template, Opt_keyrings,
     Opt_label, Opt_err
 };
 
 static const 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_hash, "hash"},
     {Opt_dont_hash, "dont_hash"},
     {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_fsname, "fsname=%s"},
     {Opt_fsuuid, "fsuuid=%s"},
     {Opt_uid_eq, "uid=%s"},
     {Opt_euid_eq, "euid=%s"},
     {Opt_gid_eq, "gid=%s"},
     {Opt_egid_eq, "egid=%s"},
     {Opt_fowner_eq, "fowner=%s"},
     {Opt_fgroup_eq, "fgroup=%s"},
     {Opt_uid_gt, "uid>%s"},
     {Opt_euid_gt, "euid>%s"},
     {Opt_gid_gt, "gid>%s"},
     {Opt_egid_gt, "egid>%s"},
     {Opt_fowner_gt, "fowner>%s"},
     {Opt_fgroup_gt, "fgroup>%s"},
     {Opt_uid_lt, "uid<%s"},
     {Opt_euid_lt, "euid<%s"},
     {Opt_gid_lt, "gid<%s"},
     {Opt_egid_lt, "egid<%s"},
     {Opt_fowner_lt, "fowner<%s"},
     {Opt_fgroup_lt, "fgroup<%s"},
     {Opt_digest_type, "digest_type=%s"},
     {Opt_appraise_type, "appraise_type=%s"},
     {Opt_appraise_flag, "appraise_flag=%s"},
     {Opt_appraise_algos, "appraise_algos=%s"},
     {Opt_permit_directio, "permit_directio"},
     {Opt_pcr, "pcr=%s"},
     {Opt_template, "template=%s"},
     {Opt_keyrings, "keyrings=%s"},
     {Opt_label, "label=%s"},
     {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 = ima_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) {
         pr_warn("rule for LSM \'%s\' is undefined\n",
             entry->lsm[lsm_rule].args_p);
 
         if (ima_rules == (struct list_head __rcu *)(&ima_default_rules)) {
             kfree(entry->lsm[lsm_rule].args_p);
             entry->lsm[lsm_rule].args_p = NULL;
             result = -EINVAL;
         } else
             result = 0;
     }
 
     return result;
 }
 
 static void ima_log_string_op(struct audit_buffer *ab, char *key, char *value,
                   enum policy_opt rule_operator)
 {
     if (!ab)
         return;
 
     switch (rule_operator) {
     case Opt_uid_gt:
     case Opt_euid_gt:
     case Opt_gid_gt:
     case Opt_egid_gt:
     case Opt_fowner_gt:
     case Opt_fgroup_gt:
         audit_log_format(ab, "%s>", key);
         break;
     case Opt_uid_lt:
     case Opt_euid_lt:
     case Opt_gid_lt:
     case Opt_egid_lt:
     case Opt_fowner_lt:
     case Opt_fgroup_lt:
         audit_log_format(ab, "%s<", key);
         break;
     default:
         audit_log_format(ab, "%s=", key);
     }
     audit_log_format(ab, "%s ", value);
 }
 static void ima_log_string(struct audit_buffer *ab, char *key, char *value)
 {
     ima_log_string_op(ab, key, value, Opt_err);
 }
 
 /*
  * Validating the appended signature included in the measurement list requires
  * the file hash calculated without the appended signature (i.e., the 'd-modsig'
  * field). Therefore, notify the user if they have the 'modsig' field but not
  * the 'd-modsig' field in the template.
  */
 static void check_template_modsig(const struct ima_template_desc *template)
 {
 #define MSG "template with 'modsig' field also needs 'd-modsig' field\n"
     bool has_modsig, has_dmodsig;
     static bool checked;
     int i;
 
     /* We only need to notify the user once. */
     if (checked)
         return;
 
     has_modsig = has_dmodsig = false;
     for (i = 0; i < template->num_fields; i++) {
         if (!strcmp(template->fields[i]->field_id, "modsig"))
             has_modsig = true;
         else if (!strcmp(template->fields[i]->field_id, "d-modsig"))
             has_dmodsig = true;
     }
 
     if (has_modsig && !has_dmodsig)
         pr_notice(MSG);
 
     checked = true;
 #undef MSG
 }
 
 /*
  * Warn if the template does not contain the given field.
  */
 static void check_template_field(const struct ima_template_desc *template,
                  const char *field, const char *msg)
 {
     int i;
 
     for (i = 0; i < template->num_fields; i++)
         if (!strcmp(template->fields[i]->field_id, field))
             return;
 
     pr_notice_once("%s", msg);
 }
 
 static bool ima_validate_rule(struct ima_rule_entry *entry)
 {
     /* Ensure that the action is set and is compatible with the flags */
     if (entry->action == UNKNOWN)
         return false;
 
     if (entry->action != MEASURE && entry->flags & IMA_PCR)
         return false;
 
     if (entry->action != APPRAISE &&
         entry->flags & (IMA_DIGSIG_REQUIRED | IMA_MODSIG_ALLOWED |
                 IMA_CHECK_BLACKLIST | IMA_VALIDATE_ALGOS))
         return false;
 
     /*
      * The IMA_FUNC bit must be set if and only if there's a valid hook
      * function specified, and vice versa. Enforcing this property allows
      * for the NONE case below to validate a rule without an explicit hook
      * function.
      */
     if (((entry->flags & IMA_FUNC) && entry->func == NONE) ||
         (!(entry->flags & IMA_FUNC) && entry->func != NONE))
         return false;
 
     /*
      * Ensure that the hook function is compatible with the other
      * components of the rule
      */
     switch (entry->func) {
     case NONE:
     case FILE_CHECK:
     case MMAP_CHECK:
     case BPRM_CHECK:
     case CREDS_CHECK:
     case POST_SETATTR:
     case FIRMWARE_CHECK:
     case POLICY_CHECK:
         if (entry->flags & ~(IMA_FUNC | IMA_MASK | IMA_FSMAGIC |
                      IMA_UID | IMA_FOWNER | IMA_FSUUID |
                      IMA_INMASK | IMA_EUID | IMA_PCR |
                      IMA_FSNAME | IMA_GID | IMA_EGID |
                      IMA_FGROUP | IMA_DIGSIG_REQUIRED |
                      IMA_PERMIT_DIRECTIO | IMA_VALIDATE_ALGOS |
                      IMA_VERITY_REQUIRED))
             return false;
 
         break;
     case MODULE_CHECK:
     case KEXEC_KERNEL_CHECK:
     case KEXEC_INITRAMFS_CHECK:
         if (entry->flags & ~(IMA_FUNC | IMA_MASK | IMA_FSMAGIC |
                      IMA_UID | IMA_FOWNER | IMA_FSUUID |
                      IMA_INMASK | IMA_EUID | IMA_PCR |
                      IMA_FSNAME | IMA_GID | IMA_EGID |
                      IMA_FGROUP | IMA_DIGSIG_REQUIRED |
                      IMA_PERMIT_DIRECTIO | IMA_MODSIG_ALLOWED |
                      IMA_CHECK_BLACKLIST | IMA_VALIDATE_ALGOS))
             return false;
 
         break;
     case KEXEC_CMDLINE:
         if (entry->action & ~(MEASURE | DONT_MEASURE))
             return false;
 
         if (entry->flags & ~(IMA_FUNC | IMA_FSMAGIC | IMA_UID |
                      IMA_FOWNER | IMA_FSUUID | IMA_EUID |
                      IMA_PCR | IMA_FSNAME | IMA_GID | IMA_EGID |
                      IMA_FGROUP))
             return false;
 
         break;
     case KEY_CHECK:
         if (entry->action & ~(MEASURE | DONT_MEASURE))
             return false;
 
         if (entry->flags & ~(IMA_FUNC | IMA_UID | IMA_GID | IMA_PCR |
                      IMA_KEYRINGS))
             return false;
 
         if (ima_rule_contains_lsm_cond(entry))
             return false;
 
         break;
     case CRITICAL_DATA:
         if (entry->action & ~(MEASURE | DONT_MEASURE))
             return false;
 
         if (entry->flags & ~(IMA_FUNC | IMA_UID | IMA_GID | IMA_PCR |
                      IMA_LABEL))
             return false;
 
         if (ima_rule_contains_lsm_cond(entry))
             return false;
 
         break;
     case SETXATTR_CHECK:
         /* any action other than APPRAISE is unsupported */
         if (entry->action != APPRAISE)
             return false;
 
         /* SETXATTR_CHECK requires an appraise_algos parameter */
         if (!(entry->flags & IMA_VALIDATE_ALGOS))
             return false;
 
         /*
          * full policies are not supported, they would have too
          * much of a performance impact
          */
         if (entry->flags & ~(IMA_FUNC | IMA_VALIDATE_ALGOS))
             return false;
 
         break;
     default:
         return false;
     }
 
     /* Ensure that combinations of flags are compatible with each other */
     if (entry->flags & IMA_CHECK_BLACKLIST &&
         !(entry->flags & IMA_MODSIG_ALLOWED))
         return false;
 
     /*
      * Unlike for regular IMA 'appraise' policy rules where security.ima
      * xattr may contain either a file hash or signature, the security.ima
      * xattr for fsverity must contain a file signature (sigv3).  Ensure
      * that 'appraise' rules for fsverity require file signatures by
      * checking the IMA_DIGSIG_REQUIRED flag is set.
      */
     if (entry->action == APPRAISE &&
         (entry->flags & IMA_VERITY_REQUIRED) &&
         !(entry->flags & IMA_DIGSIG_REQUIRED))
         return false;
 
     return true;
 }
 
 static unsigned int ima_parse_appraise_algos(char *arg)
 {
     unsigned int res = 0;
     int idx;
     char *token;
 
     while ((token = strsep(&arg, ",")) != NULL) {
         idx = match_string(hash_algo_name, HASH_ALGO__LAST, token);
 
         if (idx < 0) {
             pr_err("unknown hash algorithm \"%s\"",
                    token);
             return 0;
         }
 
         if (!crypto_has_alg(hash_algo_name[idx], 0, 0)) {
             pr_err("unavailable hash algorithm \"%s\", check your kernel configuration",
                    token);
             return 0;
         }
 
         /* Add the hash algorithm to the 'allowed' bitfield */
         res |= (1U << idx);
     }
 
     return res;
 }
 
 static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
 {
     struct audit_buffer *ab;
     char *from;
     char *p;
     bool eid_token; /* either euid or egid */
     struct ima_template_desc *template_desc;
     int result = 0;
 
     ab = integrity_audit_log_start(audit_context(), GFP_KERNEL,
                        AUDIT_INTEGRITY_POLICY_RULE);
 
     entry->uid = INVALID_UID;
     entry->gid = INVALID_GID;
     entry->fowner = INVALID_UID;
     entry->fgroup = INVALID_GID;
     entry->uid_op = &uid_eq;
     entry->gid_op = &gid_eq;
     entry->fowner_op = &uid_eq;
     entry->fgroup_op = &gid_eq;
     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_hash:
             ima_log_string(ab, "action", "hash");
 
             if (entry->action != UNKNOWN)
                 result = -EINVAL;
 
             entry->action = HASH;
             break;
         case Opt_dont_hash:
             ima_log_string(ab, "action", "dont_hash");
 
             if (entry->action != UNKNOWN)
                 result = -EINVAL;
 
             entry->action = DONT_HASH;
             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 if (strcmp(args[0].from, "CREDS_CHECK") == 0)
                 entry->func = CREDS_CHECK;
             else if (strcmp(args[0].from, "KEXEC_KERNEL_CHECK") ==
                  0)
                 entry->func = KEXEC_KERNEL_CHECK;
             else if (strcmp(args[0].from, "KEXEC_INITRAMFS_CHECK")
                  == 0)
                 entry->func = KEXEC_INITRAMFS_CHECK;
             else if (strcmp(args[0].from, "POLICY_CHECK") == 0)
                 entry->func = POLICY_CHECK;
             else if (strcmp(args[0].from, "KEXEC_CMDLINE") == 0)
                 entry->func = KEXEC_CMDLINE;
             else if (IS_ENABLED(CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS) &&
                  strcmp(args[0].from, "KEY_CHECK") == 0)
                 entry->func = KEY_CHECK;
             else if (strcmp(args[0].from, "CRITICAL_DATA") == 0)
                 entry->func = CRITICAL_DATA;
             else if (strcmp(args[0].from, "SETXATTR_CHECK") == 0)
                 entry->func = SETXATTR_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_fsname:
             ima_log_string(ab, "fsname", args[0].from);
 
             entry->fsname = kstrdup(args[0].from, GFP_KERNEL);
             if (!entry->fsname) {
                 result = -ENOMEM;
                 break;
             }
             result = 0;
             entry->flags |= IMA_FSNAME;
             break;
         case Opt_keyrings:
             ima_log_string(ab, "keyrings", args[0].from);
 
             if (!IS_ENABLED(CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS) ||
                 entry->keyrings) {
                 result = -EINVAL;
                 break;
             }
 
             entry->keyrings = ima_alloc_rule_opt_list(args);
             if (IS_ERR(entry->keyrings)) {
                 result = PTR_ERR(entry->keyrings);
                 entry->keyrings = NULL;
                 break;
             }
 
             entry->flags |= IMA_KEYRINGS;
             break;
         case Opt_label:
             ima_log_string(ab, "label", args[0].from);
 
             if (entry->label) {
                 result = -EINVAL;
                 break;
             }
 
             entry->label = ima_alloc_rule_opt_list(args);
             if (IS_ERR(entry->label)) {
                 result = PTR_ERR(entry->label);
                 entry->label = NULL;
                 break;
             }
 
             entry->flags |= IMA_LABEL;
             break;
         case Opt_fsuuid:
             ima_log_string(ab, "fsuuid", args[0].from);
 
             if (!uuid_is_null(&entry->fsuuid)) {
                 result = -EINVAL;
                 break;
             }
 
             result = uuid_parse(args[0].from, &entry->fsuuid);
             if (!result)
                 entry->flags |= IMA_FSUUID;
             break;
         case Opt_uid_gt:
         case Opt_euid_gt:
             entry->uid_op = &uid_gt;
             fallthrough;
         case Opt_uid_lt:
         case Opt_euid_lt:
             if ((token == Opt_uid_lt) || (token == Opt_euid_lt))
                 entry->uid_op = &uid_lt;
             fallthrough;
         case Opt_uid_eq:
         case Opt_euid_eq:
             eid_token = (token == Opt_euid_eq) ||
                     (token == Opt_euid_gt) ||
                     (token == Opt_euid_lt);
 
             ima_log_string_op(ab, eid_token ? "euid" : "uid",
                       args[0].from, token);
 
             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 |= eid_token
                         ? IMA_EUID : IMA_UID;
             }
             break;
         case Opt_gid_gt:
         case Opt_egid_gt:
             entry->gid_op = &gid_gt;
             fallthrough;
         case Opt_gid_lt:
         case Opt_egid_lt:
             if ((token == Opt_gid_lt) || (token == Opt_egid_lt))
                 entry->gid_op = &gid_lt;
             fallthrough;
         case Opt_gid_eq:
         case Opt_egid_eq:
             eid_token = (token == Opt_egid_eq) ||
                     (token == Opt_egid_gt) ||
                     (token == Opt_egid_lt);
 
             ima_log_string_op(ab, eid_token ? "egid" : "gid",
                       args[0].from, token);
 
             if (gid_valid(entry->gid)) {
                 result = -EINVAL;
                 break;
             }
 
             result = kstrtoul(args[0].from, 10, &lnum);
             if (!result) {
                 entry->gid = make_kgid(current_user_ns(),
                                (gid_t)lnum);
                 if (!gid_valid(entry->gid) ||
                     (((gid_t)lnum) != lnum))
                     result = -EINVAL;
                 else
                     entry->flags |= eid_token
                         ? IMA_EGID : IMA_GID;
             }
             break;
         case Opt_fowner_gt:
             entry->fowner_op = &uid_gt;
             fallthrough;
         case Opt_fowner_lt:
             if (token == Opt_fowner_lt)
                 entry->fowner_op = &uid_lt;
             fallthrough;
         case Opt_fowner_eq:
             ima_log_string_op(ab, "fowner", args[0].from, token);
 
             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_fgroup_gt:
             entry->fgroup_op = &gid_gt;
             fallthrough;
         case Opt_fgroup_lt:
             if (token == Opt_fgroup_lt)
                 entry->fgroup_op = &gid_lt;
             fallthrough;
         case Opt_fgroup_eq:
             ima_log_string_op(ab, "fgroup", args[0].from, token);
 
             if (gid_valid(entry->fgroup)) {
                 result = -EINVAL;
                 break;
             }
 
             result = kstrtoul(args[0].from, 10, &lnum);
             if (!result) {
                 entry->fgroup = make_kgid(current_user_ns(),
                               (gid_t)lnum);
                 if (!gid_valid(entry->fgroup) ||
                     (((gid_t)lnum) != lnum))
                     result = -EINVAL;
                 else
                     entry->flags |= IMA_FGROUP;
             }
             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_digest_type:
             ima_log_string(ab, "digest_type", args[0].from);
             if (entry->flags & IMA_DIGSIG_REQUIRED)
                 result = -EINVAL;
             else if ((strcmp(args[0].from, "verity")) == 0)
                 entry->flags |= IMA_VERITY_REQUIRED;
             else
                 result = -EINVAL;
             break;
         case Opt_appraise_type:
             ima_log_string(ab, "appraise_type", args[0].from);
 
             if ((strcmp(args[0].from, "imasig")) == 0) {
                 if (entry->flags & IMA_VERITY_REQUIRED)
                     result = -EINVAL;
                 else
                     entry->flags |= IMA_DIGSIG_REQUIRED;
             } else if (strcmp(args[0].from, "sigv3") == 0) {
                 /* Only fsverity supports sigv3 for now */
                 if (entry->flags & IMA_VERITY_REQUIRED)
                     entry->flags |= IMA_DIGSIG_REQUIRED;
                 else
                     result = -EINVAL;
             } else if (IS_ENABLED(CONFIG_IMA_APPRAISE_MODSIG) &&
                  strcmp(args[0].from, "imasig|modsig") == 0) {
                 if (entry->flags & IMA_VERITY_REQUIRED)
                     result = -EINVAL;
                 else
                     entry->flags |= IMA_DIGSIG_REQUIRED |
                         IMA_MODSIG_ALLOWED;
             } else {
                 result = -EINVAL;
             }
             break;
         case Opt_appraise_flag:
             ima_log_string(ab, "appraise_flag", args[0].from);
             if (IS_ENABLED(CONFIG_IMA_APPRAISE_MODSIG) &&
                 strstr(args[0].from, "blacklist"))
                 entry->flags |= IMA_CHECK_BLACKLIST;
             else
                 result = -EINVAL;
             break;
         case Opt_appraise_algos:
             ima_log_string(ab, "appraise_algos", args[0].from);
 
             if (entry->allowed_algos) {
                 result = -EINVAL;
                 break;
             }
 
             entry->allowed_algos =
                 ima_parse_appraise_algos(args[0].from);
             /* invalid or empty list of algorithms */
             if (!entry->allowed_algos) {
                 result = -EINVAL;
                 break;
             }
 
             entry->flags |= IMA_VALIDATE_ALGOS;
 
             break;
         case Opt_permit_directio:
             entry->flags |= IMA_PERMIT_DIRECTIO;
             break;
         case Opt_pcr:
             ima_log_string(ab, "pcr", args[0].from);
 
             result = kstrtoint(args[0].from, 10, &entry->pcr);
             if (result || INVALID_PCR(entry->pcr))
                 result = -EINVAL;
             else
                 entry->flags |= IMA_PCR;
 
             break;
         case Opt_template:
             ima_log_string(ab, "template", args[0].from);
             if (entry->action != MEASURE) {
                 result = -EINVAL;
                 break;
             }
             template_desc = lookup_template_desc(args[0].from);
             if (!template_desc || entry->template) {
                 result = -EINVAL;
                 break;
             }
 
             /*
              * template_desc_init_fields() does nothing if
              * the template is already initialised, so
              * it's safe to do this unconditionally
              */
             template_desc_init_fields(template_desc->fmt,
                          &(template_desc->fields),
                          &(template_desc->num_fields));
             entry->template = template_desc;
             break;
         case Opt_err:
             ima_log_string(ab, "UNKNOWN", p);
             result = -EINVAL;
             break;
         }
     }
     if (!result && !ima_validate_rule(entry))
         result = -EINVAL;
     else if (entry->action == APPRAISE)
         temp_ima_appraise |= ima_appraise_flag(entry->func);
 
     if (!result && entry->flags & IMA_MODSIG_ALLOWED) {
         template_desc = entry->template ? entry->template :
                           ima_template_desc_current();
         check_template_modsig(template_desc);
     }
 
     /* d-ngv2 template field recommended for unsigned fs-verity digests */
     if (!result && entry->action == MEASURE &&
         entry->flags & IMA_VERITY_REQUIRED) {
         template_desc = entry->template ? entry->template :
                           ima_template_desc_current();
         check_template_field(template_desc, "d-ngv2",
                      "verity rules should include d-ngv2");
     }
 
     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
  *
  * Avoid locking by allowing just one writer at a time in ima_write_policy()
  * 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) {
         ima_free_rule(entry);
         integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
                     NULL, op, "invalid-policy", result,
                     audit_info);
         return result;
     }
 
     list_add_tail(&entry->list, &ima_temp_rules);
 
     return len;
 }
 
 /**
  * ima_delete_rules() called to cleanup invalid in-flight policy.
  * We don't need locking as we operate on the temp list, which is
  * different from the active one.  There is also only one user of
  * ima_delete_rules() at a time.
  */
 void ima_delete_rules(void)
 {
     struct ima_rule_entry *entry, *tmp;
 
     temp_ima_appraise = 0;
     list_for_each_entry_safe(entry, tmp, &ima_temp_rules, list) {
         list_del(&entry->list);
         ima_free_rule(entry);
     }
 }
 
 #define __ima_hook_stringify(func, str) (#func),
 
 const char *const func_tokens[] = {
     __ima_hooks(__ima_hook_stringify)
 };
 
 #ifdef  CONFIG_IMA_READ_POLICY
 enum {
     mask_exec = 0, mask_write, mask_read, mask_append
 };
 
 static const char *const mask_tokens[] = {
     "^MAY_EXEC",
     "^MAY_WRITE",
     "^MAY_READ",
     "^MAY_APPEND"
 };
 
 void *ima_policy_start(struct seq_file *m, loff_t *pos)
 {
     loff_t l = *pos;
     struct ima_rule_entry *entry;
     struct list_head *ima_rules_tmp;
 
     rcu_read_lock();
     ima_rules_tmp = rcu_dereference(ima_rules);
     list_for_each_entry_rcu(entry, ima_rules_tmp, list) {
         if (!l--) {
             rcu_read_unlock();
             return entry;
         }
     }
     rcu_read_unlock();
     return NULL;
 }
 
 void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos)
 {
     struct ima_rule_entry *entry = v;
 
     rcu_read_lock();
     entry = list_entry_rcu(entry->list.next, struct ima_rule_entry, list);
     rcu_read_unlock();
     (*pos)++;
 
     return (&entry->list == &ima_default_rules ||
         &entry->list == &ima_policy_rules) ? NULL : entry;
 }
 
 void ima_policy_stop(struct seq_file *m, void *v)
 {
 }
 
 #define pt(token)   policy_tokens[token].pattern
 #define mt(token)   mask_tokens[token]
 
 /*
  * policy_func_show - display the ima_hooks policy rule
  */
 static void policy_func_show(struct seq_file *m, enum ima_hooks func)
 {
     if (func > 0 && func < MAX_CHECK)
         seq_printf(m, "func=%s ", func_tokens[func]);
     else
         seq_printf(m, "func=%d ", func);
 }
 
 static void ima_show_rule_opt_list(struct seq_file *m,
                    const struct ima_rule_opt_list *opt_list)
 {
     size_t i;
 
     for (i = 0; i < opt_list->count; i++)
         seq_printf(m, "%s%s", i ? "|" : "", opt_list->items[i]);
 }
 
 static void ima_policy_show_appraise_algos(struct seq_file *m,
                        unsigned int allowed_hashes)
 {
     int idx, list_size = 0;
 
     for (idx = 0; idx < HASH_ALGO__LAST; idx++) {
         if (!(allowed_hashes & (1U << idx)))
             continue;
 
         /* only add commas if the list contains multiple entries */
         if (list_size++)
             seq_puts(m, ",");
 
         seq_puts(m, hash_algo_name[idx]);
     }
 }
 
 int ima_policy_show(struct seq_file *m, void *v)
 {
     struct ima_rule_entry *entry = v;
     int i;
     char tbuf[64] = {0,};
     int offset = 0;
 
     rcu_read_lock();
 
     /* Do not print rules with inactive LSM labels */
     for (i = 0; i < MAX_LSM_RULES; i++) {
         if (entry->lsm[i].args_p && !entry->lsm[i].rule) {
             rcu_read_unlock();
             return 0;
         }
     }
 
     if (entry->action & MEASURE)
         seq_puts(m, pt(Opt_measure));
     if (entry->action & DONT_MEASURE)
         seq_puts(m, pt(Opt_dont_measure));
     if (entry->action & APPRAISE)
         seq_puts(m, pt(Opt_appraise));
     if (entry->action & DONT_APPRAISE)
         seq_puts(m, pt(Opt_dont_appraise));
     if (entry->action & AUDIT)
         seq_puts(m, pt(Opt_audit));
     if (entry->action & HASH)
         seq_puts(m, pt(Opt_hash));
     if (entry->action & DONT_HASH)
         seq_puts(m, pt(Opt_dont_hash));
 
     seq_puts(m, " ");
 
     if (entry->flags & IMA_FUNC)
         policy_func_show(m, entry->func);
 
     if ((entry->flags & IMA_MASK) || (entry->flags & IMA_INMASK)) {
         if (entry->flags & IMA_MASK)
             offset = 1;
         if (entry->mask & MAY_EXEC)
             seq_printf(m, pt(Opt_mask), mt(mask_exec) + offset);
         if (entry->mask & MAY_WRITE)
             seq_printf(m, pt(Opt_mask), mt(mask_write) + offset);
         if (entry->mask & MAY_READ)
             seq_printf(m, pt(Opt_mask), mt(mask_read) + offset);
         if (entry->mask & MAY_APPEND)
             seq_printf(m, pt(Opt_mask), mt(mask_append) + offset);
         seq_puts(m, " ");
     }
 
     if (entry->flags & IMA_FSMAGIC) {
         snprintf(tbuf, sizeof(tbuf), "0x%lx", entry->fsmagic);
         seq_printf(m, pt(Opt_fsmagic), tbuf);
         seq_puts(m, " ");
     }
 
     if (entry->flags & IMA_FSNAME) {
         snprintf(tbuf, sizeof(tbuf), "%s", entry->fsname);
         seq_printf(m, pt(Opt_fsname), tbuf);
         seq_puts(m, " ");
     }
 
     if (entry->flags & IMA_KEYRINGS) {
         seq_puts(m, "keyrings=");
         ima_show_rule_opt_list(m, entry->keyrings);
         seq_puts(m, " ");
     }
 
     if (entry->flags & IMA_LABEL) {
         seq_puts(m, "label=");
         ima_show_rule_opt_list(m, entry->label);
         seq_puts(m, " ");
     }
 
     if (entry->flags & IMA_PCR) {
         snprintf(tbuf, sizeof(tbuf), "%d", entry->pcr);
         seq_printf(m, pt(Opt_pcr), tbuf);
         seq_puts(m, " ");
     }
 
     if (entry->flags & IMA_FSUUID) {
         seq_printf(m, "fsuuid=%pU", &entry->fsuuid);
         seq_puts(m, " ");
     }
 
     if (entry->flags & IMA_UID) {
         snprintf(tbuf, sizeof(tbuf), "%d", __kuid_val(entry->uid));
         if (entry->uid_op == &uid_gt)
             seq_printf(m, pt(Opt_uid_gt), tbuf);
         else if (entry->uid_op == &uid_lt)
             seq_printf(m, pt(Opt_uid_lt), tbuf);
         else
             seq_printf(m, pt(Opt_uid_eq), tbuf);
         seq_puts(m, " ");
     }
 
     if (entry->flags & IMA_EUID) {
         snprintf(tbuf, sizeof(tbuf), "%d", __kuid_val(entry->uid));
         if (entry->uid_op == &uid_gt)
             seq_printf(m, pt(Opt_euid_gt), tbuf);
         else if (entry->uid_op == &uid_lt)
             seq_printf(m, pt(Opt_euid_lt), tbuf);
         else
             seq_printf(m, pt(Opt_euid_eq), tbuf);
         seq_puts(m, " ");
     }
 
     if (entry->flags & IMA_GID) {
         snprintf(tbuf, sizeof(tbuf), "%d", __kgid_val(entry->gid));
         if (entry->gid_op == &gid_gt)
             seq_printf(m, pt(Opt_gid_gt), tbuf);
         else if (entry->gid_op == &gid_lt)
             seq_printf(m, pt(Opt_gid_lt), tbuf);
         else
             seq_printf(m, pt(Opt_gid_eq), tbuf);
         seq_puts(m, " ");
     }
 
     if (entry->flags & IMA_EGID) {
         snprintf(tbuf, sizeof(tbuf), "%d", __kgid_val(entry->gid));
         if (entry->gid_op == &gid_gt)
             seq_printf(m, pt(Opt_egid_gt), tbuf);
         else if (entry->gid_op == &gid_lt)
             seq_printf(m, pt(Opt_egid_lt), tbuf);
         else
             seq_printf(m, pt(Opt_egid_eq), tbuf);
         seq_puts(m, " ");
     }
 
     if (entry->flags & IMA_FOWNER) {
         snprintf(tbuf, sizeof(tbuf), "%d", __kuid_val(entry->fowner));
         if (entry->fowner_op == &uid_gt)
             seq_printf(m, pt(Opt_fowner_gt), tbuf);
         else if (entry->fowner_op == &uid_lt)
             seq_printf(m, pt(Opt_fowner_lt), tbuf);
         else
             seq_printf(m, pt(Opt_fowner_eq), tbuf);
         seq_puts(m, " ");
     }
 
     if (entry->flags & IMA_FGROUP) {
         snprintf(tbuf, sizeof(tbuf), "%d", __kgid_val(entry->fgroup));
         if (entry->fgroup_op == &gid_gt)
             seq_printf(m, pt(Opt_fgroup_gt), tbuf);
         else if (entry->fgroup_op == &gid_lt)
             seq_printf(m, pt(Opt_fgroup_lt), tbuf);
         else
             seq_printf(m, pt(Opt_fgroup_eq), tbuf);
         seq_puts(m, " ");
     }
 
     if (entry->flags & IMA_VALIDATE_ALGOS) {
         seq_puts(m, "appraise_algos=");
         ima_policy_show_appraise_algos(m, entry->allowed_algos);
         seq_puts(m, " ");
     }
 
     for (i = 0; i < MAX_LSM_RULES; i++) {
         if (entry->lsm[i].rule) {
             switch (i) {
             case LSM_OBJ_USER:
                 seq_printf(m, pt(Opt_obj_user),
                        entry->lsm[i].args_p);
                 break;
             case LSM_OBJ_ROLE:
                 seq_printf(m, pt(Opt_obj_role),
                        entry->lsm[i].args_p);
                 break;
             case LSM_OBJ_TYPE:
                 seq_printf(m, pt(Opt_obj_type),
                        entry->lsm[i].args_p);
                 break;
             case LSM_SUBJ_USER:
                 seq_printf(m, pt(Opt_subj_user),
                        entry->lsm[i].args_p);
                 break;
             case LSM_SUBJ_ROLE:
                 seq_printf(m, pt(Opt_subj_role),
                        entry->lsm[i].args_p);
                 break;
             case LSM_SUBJ_TYPE:
                 seq_printf(m, pt(Opt_subj_type),
                        entry->lsm[i].args_p);
                 break;
             }
             seq_puts(m, " ");
         }
     }
     if (entry->template)
         seq_printf(m, "template=%s ", entry->template->name);
     if (entry->flags & IMA_DIGSIG_REQUIRED) {
         if (entry->flags & IMA_VERITY_REQUIRED)
             seq_puts(m, "appraise_type=sigv3 ");
         else if (entry->flags & IMA_MODSIG_ALLOWED)
             seq_puts(m, "appraise_type=imasig|modsig ");
         else
             seq_puts(m, "appraise_type=imasig ");
     }
     if (entry->flags & IMA_VERITY_REQUIRED)
         seq_puts(m, "digest_type=verity ");
     if (entry->flags & IMA_CHECK_BLACKLIST)
         seq_puts(m, "appraise_flag=check_blacklist ");
     if (entry->flags & IMA_PERMIT_DIRECTIO)
         seq_puts(m, "permit_directio ");
     rcu_read_unlock();
     seq_puts(m, "\n");
     return 0;
 }
 #endif  /* CONFIG_IMA_READ_POLICY */
 
 #if defined(CONFIG_IMA_APPRAISE) && defined(CONFIG_INTEGRITY_TRUSTED_KEYRING)
 /*
  * ima_appraise_signature: whether IMA will appraise a given function using
  * an IMA digital signature. This is restricted to cases where the kernel
  * has a set of built-in trusted keys in order to avoid an attacker simply
  * loading additional keys.
  */
 bool ima_appraise_signature(enum kernel_read_file_id id)
 {
     struct ima_rule_entry *entry;
     bool found = false;
     enum ima_hooks func;
     struct list_head *ima_rules_tmp;
 
     if (id >= READING_MAX_ID)
         return false;
 
     if (id == READING_KEXEC_IMAGE && !(ima_appraise & IMA_APPRAISE_ENFORCE)
         && security_locked_down(LOCKDOWN_KEXEC))
         return false;
 
     func = read_idmap[id] ?: FILE_CHECK;
 
     rcu_read_lock();
     ima_rules_tmp = rcu_dereference(ima_rules);
     list_for_each_entry_rcu(entry, ima_rules_tmp, list) {
         if (entry->action != APPRAISE)
             continue;
 
         /*
          * A generic entry will match, but otherwise require that it
          * match the func we're looking for
          */
         if (entry->func && entry->func != func)
             continue;
 
         /*
          * We require this to be a digital signature, not a raw IMA
          * hash.
          */
         if (entry->flags & IMA_DIGSIG_REQUIRED)
             found = true;
 
         /*
          * We've found a rule that matches, so break now even if it
          * didn't require a digital signature - a later rule that does
          * won't override it, so would be a false positive.
          */
         break;
     }
 
     rcu_read_unlock();
     return found;
 }
 #endif /* CONFIG_IMA_APPRAISE && CONFIG_INTEGRITY_TRUSTED_KEYRING */

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