mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-22 00:40:03 +00:00
![Mimi Zohar](/assets/img/avatar_default.png)
Commit "85865c1 ima: add policy support for file system uuid" introduced a CONFIG_BLOCK dependency. This patch defines a wrapper called blk_part_pack_uuid(), which returns -EINVAL, when CONFIG_BLOCK is not defined. security/integrity/ima/ima_policy.c:538:4: error: implicit declaration of function 'part_pack_uuid' [-Werror=implicit-function-declaration] Changelog v2: - Reference commit number in patch description Changelog v1: - rename ima_part_pack_uuid() to blk_part_pack_uuid() - resolve scripts/checkpatch.pl warnings Changelog v0: - fix UUID scripts/Lindent msgs Reported-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: David Rientjes <rientjes@google.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: James Morris <james.l.morris@oracle.com>
711 lines
18 KiB
C
711 lines
18 KiB
C
/*
|
|
* 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 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 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
|
|
};
|
|
|
|
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 default_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 = RAMFS_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 = 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},
|
|
};
|
|
|
|
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 = CGROUP_SUPER_MAGIC,.flags = IMA_FSMAGIC},
|
|
{.action = APPRAISE,.fowner = GLOBAL_ROOT_UID,.flags = IMA_FOWNER},
|
|
};
|
|
|
|
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 bool ima_use_tcb __initdata;
|
|
static int __init default_measure_policy_setup(char *str)
|
|
{
|
|
ima_use_tcb = 1;
|
|
return 1;
|
|
}
|
|
__setup("ima_tcb", default_measure_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)
|
|
return false;
|
|
if ((rule->flags & IMA_MASK) && rule->mask != mask)
|
|
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_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 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;
|
|
}
|
|
|
|
/**
|
|
* 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_use_tcb set entries = 0 so we load NO default rules */
|
|
measure_entries = ima_use_tcb ? ARRAY_SIZE(default_rules) : 0;
|
|
appraise_entries = ima_use_appraise_tcb ?
|
|
ARRAY_SIZE(default_appraise_rules) : 0;
|
|
|
|
for (i = 0; i < measure_entries + appraise_entries; i++) {
|
|
if (i < measure_entries)
|
|
list_add_tail(&default_rules[i].list,
|
|
&ima_default_rules);
|
|
else {
|
|
int j = i - measure_entries;
|
|
|
|
list_add_tail(&default_appraise_rules[j].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)
|
|
{
|
|
const char *op = "policy_update";
|
|
const char *cause = "already exists";
|
|
int result = 1;
|
|
int audit_info = 0;
|
|
|
|
if (ima_rules == &ima_default_rules) {
|
|
ima_rules = &ima_policy_rules;
|
|
cause = "complete";
|
|
result = 0;
|
|
}
|
|
integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
|
|
NULL, op, cause, result, audit_info);
|
|
}
|
|
|
|
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_fowner,
|
|
Opt_appraise_type, Opt_fsuuid
|
|
};
|
|
|
|
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_fowner, "fowner=%s"},
|
|
{Opt_appraise_type, "appraise_type=%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 = 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 *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, "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;
|
|
|
|
if ((strcmp(args[0].from, "MAY_EXEC")) == 0)
|
|
entry->mask = MAY_EXEC;
|
|
else if (strcmp(args[0].from, "MAY_WRITE") == 0)
|
|
entry->mask = MAY_WRITE;
|
|
else if (strcmp(args[0].from, "MAY_READ") == 0)
|
|
entry->mask = MAY_READ;
|
|
else if (strcmp(args[0].from, "MAY_APPEND") == 0)
|
|
entry->mask = MAY_APPEND;
|
|
else
|
|
result = -EINVAL;
|
|
if (!result)
|
|
entry->flags |= IMA_MASK;
|
|
break;
|
|
case Opt_fsmagic:
|
|
ima_log_string(ab, "fsmagic", args[0].from);
|
|
|
|
if (entry->fsmagic) {
|
|
result = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
result = strict_strtoul(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);
|
|
|
|
if (uid_valid(entry->uid)) {
|
|
result = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
result = strict_strtoul(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 |= IMA_UID;
|
|
}
|
|
break;
|
|
case Opt_fowner:
|
|
ima_log_string(ab, "fowner", args[0].from);
|
|
|
|
if (uid_valid(entry->fowner)) {
|
|
result = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
result = strict_strtoul(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_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;
|
|
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)
|
|
{
|
|
const char *op = "update_policy";
|
|
char *p;
|
|
struct ima_rule_entry *entry;
|
|
ssize_t result, len;
|
|
int audit_info = 0;
|
|
|
|
/* Prevent installed policy from changing */
|
|
if (ima_rules != &ima_default_rules) {
|
|
integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
|
|
NULL, op, "already exists",
|
|
-EACCES, audit_info);
|
|
return -EACCES;
|
|
}
|
|
|
|
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);
|
|
|
|
p = strsep(&rule, "\n");
|
|
len = strlen(p) + 1;
|
|
|
|
if (*p == '#') {
|
|
kfree(entry);
|
|
return len;
|
|
}
|
|
|
|
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);
|
|
}
|