blob: d818717954f89ba28b6eedac1b07f2d5f98862ed [file] [log] [blame]
/*
* security/tomoyo/domain.c
*
* Domain transition functions for TOMOYO.
*
* Copyright (C) 2005-2010 NTT DATA CORPORATION
*/
#include "common.h"
#include <linux/binfmts.h>
#include <linux/slab.h>
/* Variables definitions.*/
/* The initial domain. */
struct tomoyo_domain_info tomoyo_kernel_domain;
/**
* tomoyo_update_policy - Update an entry for exception policy.
*
* @new_entry: Pointer to "struct tomoyo_acl_info".
* @size: Size of @new_entry in bytes.
* @param: Pointer to "struct tomoyo_acl_param".
* @check_duplicate: Callback function to find duplicated entry.
*
* Returns 0 on success, negative value otherwise.
*
* Caller holds tomoyo_read_lock().
*/
int tomoyo_update_policy(struct tomoyo_acl_head *new_entry, const int size,
struct tomoyo_acl_param *param,
bool (*check_duplicate) (const struct tomoyo_acl_head
*,
const struct tomoyo_acl_head
*))
{
int error = param->is_delete ? -ENOENT : -ENOMEM;
struct tomoyo_acl_head *entry;
struct list_head *list = param->list;
if (mutex_lock_interruptible(&tomoyo_policy_lock))
return -ENOMEM;
list_for_each_entry_rcu(entry, list, list) {
if (!check_duplicate(entry, new_entry))
continue;
entry->is_deleted = param->is_delete;
error = 0;
break;
}
if (error && !param->is_delete) {
entry = tomoyo_commit_ok(new_entry, size);
if (entry) {
list_add_tail_rcu(&entry->list, list);
error = 0;
}
}
mutex_unlock(&tomoyo_policy_lock);
return error;
}
/**
* tomoyo_same_acl_head - Check for duplicated "struct tomoyo_acl_info" entry.
*
* @a: Pointer to "struct tomoyo_acl_info".
* @b: Pointer to "struct tomoyo_acl_info".
*
* Returns true if @a == @b, false otherwise.
*/
static inline bool tomoyo_same_acl_head(const struct tomoyo_acl_info *a,
const struct tomoyo_acl_info *b)
{
return a->type == b->type;
}
/**
* tomoyo_update_domain - Update an entry for domain policy.
*
* @new_entry: Pointer to "struct tomoyo_acl_info".
* @size: Size of @new_entry in bytes.
* @param: Pointer to "struct tomoyo_acl_param".
* @check_duplicate: Callback function to find duplicated entry.
* @merge_duplicate: Callback function to merge duplicated entry.
*
* Returns 0 on success, negative value otherwise.
*
* Caller holds tomoyo_read_lock().
*/
int tomoyo_update_domain(struct tomoyo_acl_info *new_entry, const int size,
struct tomoyo_acl_param *param,
bool (*check_duplicate) (const struct tomoyo_acl_info
*,
const struct tomoyo_acl_info
*),
bool (*merge_duplicate) (struct tomoyo_acl_info *,
struct tomoyo_acl_info *,
const bool))
{
const bool is_delete = param->is_delete;
int error = is_delete ? -ENOENT : -ENOMEM;
struct tomoyo_acl_info *entry;
struct list_head * const list = param->list;
if (mutex_lock_interruptible(&tomoyo_policy_lock))
return error;
list_for_each_entry_rcu(entry, list, list) {
if (!tomoyo_same_acl_head(entry, new_entry) ||
!check_duplicate(entry, new_entry))
continue;
if (merge_duplicate)
entry->is_deleted = merge_duplicate(entry, new_entry,
is_delete);
else
entry->is_deleted = is_delete;
error = 0;
break;
}
if (error && !is_delete) {
entry = tomoyo_commit_ok(new_entry, size);
if (entry) {
list_add_tail_rcu(&entry->list, list);
error = 0;
}
}
mutex_unlock(&tomoyo_policy_lock);
return error;
}
void tomoyo_check_acl(struct tomoyo_request_info *r,
bool (*check_entry) (struct tomoyo_request_info *,
const struct tomoyo_acl_info *))
{
const struct tomoyo_domain_info *domain = r->domain;
struct tomoyo_acl_info *ptr;
list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
if (ptr->is_deleted || ptr->type != r->param_type)
continue;
if (check_entry(r, ptr)) {
r->granted = true;
return;
}
}
r->granted = false;
}
/* The list for "struct tomoyo_domain_info". */
LIST_HEAD(tomoyo_domain_list);
struct list_head tomoyo_policy_list[TOMOYO_MAX_POLICY];
struct list_head tomoyo_group_list[TOMOYO_MAX_GROUP];
/**
* tomoyo_last_word - Get last component of a domainname.
*
* @domainname: Domainname to check.
*
* Returns the last word of @domainname.
*/
static const char *tomoyo_last_word(const char *name)
{
const char *cp = strrchr(name, ' ');
if (cp)
return cp + 1;
return name;
}
/**
* tomoyo_same_transition_control - Check for duplicated "struct tomoyo_transition_control" entry.
*
* @a: Pointer to "struct tomoyo_acl_head".
* @b: Pointer to "struct tomoyo_acl_head".
*
* Returns true if @a == @b, false otherwise.
*/
static bool tomoyo_same_transition_control(const struct tomoyo_acl_head *a,
const struct tomoyo_acl_head *b)
{
const struct tomoyo_transition_control *p1 = container_of(a,
typeof(*p1),
head);
const struct tomoyo_transition_control *p2 = container_of(b,
typeof(*p2),
head);
return p1->type == p2->type && p1->is_last_name == p2->is_last_name
&& p1->domainname == p2->domainname
&& p1->program == p2->program;
}
/**
* tomoyo_write_transition_control - Write "struct tomoyo_transition_control" list.
*
* @param: Pointer to "struct tomoyo_acl_param".
* @type: Type of this entry.
*
* Returns 0 on success, negative value otherwise.
*/
int tomoyo_write_transition_control(struct tomoyo_acl_param *param,
const u8 type)
{
struct tomoyo_transition_control e = { .type = type };
int error = param->is_delete ? -ENOENT : -ENOMEM;
char *program = param->data;
char *domainname = strstr(program, " from ");
if (domainname) {
*domainname = '\0';
domainname += 6;
} else if (type == TOMOYO_TRANSITION_CONTROL_NO_KEEP ||
type == TOMOYO_TRANSITION_CONTROL_KEEP) {
domainname = program;
program = NULL;
}
if (program) {
if (!tomoyo_correct_path(program))
return -EINVAL;
e.program = tomoyo_get_name(program);
if (!e.program)
goto out;
}
if (domainname) {
if (!tomoyo_correct_domain(domainname)) {
if (!tomoyo_correct_path(domainname))
goto out;
e.is_last_name = true;
}
e.domainname = tomoyo_get_name(domainname);
if (!e.domainname)
goto out;
}
param->list = &tomoyo_policy_list[TOMOYO_ID_TRANSITION_CONTROL];
error = tomoyo_update_policy(&e.head, sizeof(e), param,
tomoyo_same_transition_control);
out:
tomoyo_put_name(e.domainname);
tomoyo_put_name(e.program);
return error;
}
/**
* tomoyo_transition_type - Get domain transition type.
*
* @domainname: The name of domain.
* @program: The name of program.
*
* Returns TOMOYO_TRANSITION_CONTROL_INITIALIZE if executing @program
* reinitializes domain transition, TOMOYO_TRANSITION_CONTROL_KEEP if executing
* @program suppresses domain transition, others otherwise.
*
* Caller holds tomoyo_read_lock().
*/
static u8 tomoyo_transition_type(const struct tomoyo_path_info *domainname,
const struct tomoyo_path_info *program)
{
const struct tomoyo_transition_control *ptr;
const char *last_name = tomoyo_last_word(domainname->name);
u8 type;
for (type = 0; type < TOMOYO_MAX_TRANSITION_TYPE; type++) {
next:
list_for_each_entry_rcu(ptr, &tomoyo_policy_list
[TOMOYO_ID_TRANSITION_CONTROL],
head.list) {
if (ptr->head.is_deleted || ptr->type != type)
continue;
if (ptr->domainname) {
if (!ptr->is_last_name) {
if (ptr->domainname != domainname)
continue;
} else {
/*
* Use direct strcmp() since this is
* unlikely used.
*/
if (strcmp(ptr->domainname->name,
last_name))
continue;
}
}
if (ptr->program &&
tomoyo_pathcmp(ptr->program, program))
continue;
if (type == TOMOYO_TRANSITION_CONTROL_NO_INITIALIZE) {
/*
* Do not check for initialize_domain if
* no_initialize_domain matched.
*/
type = TOMOYO_TRANSITION_CONTROL_NO_KEEP;
goto next;
}
goto done;
}
}
done:
return type;
}
/**
* tomoyo_same_aggregator - Check for duplicated "struct tomoyo_aggregator" entry.
*
* @a: Pointer to "struct tomoyo_acl_head".
* @b: Pointer to "struct tomoyo_acl_head".
*
* Returns true if @a == @b, false otherwise.
*/
static bool tomoyo_same_aggregator(const struct tomoyo_acl_head *a,
const struct tomoyo_acl_head *b)
{
const struct tomoyo_aggregator *p1 = container_of(a, typeof(*p1),
head);
const struct tomoyo_aggregator *p2 = container_of(b, typeof(*p2),
head);
return p1->original_name == p2->original_name &&
p1->aggregated_name == p2->aggregated_name;
}
/**
* tomoyo_write_aggregator - Write "struct tomoyo_aggregator" list.
*
* @param: Pointer to "struct tomoyo_acl_param".
*
* Returns 0 on success, negative value otherwise.
*
* Caller holds tomoyo_read_lock().
*/
int tomoyo_write_aggregator(struct tomoyo_acl_param *param)
{
struct tomoyo_aggregator e = { };
int error = param->is_delete ? -ENOENT : -ENOMEM;
const char *original_name = tomoyo_read_token(param);
const char *aggregated_name = tomoyo_read_token(param);
if (!tomoyo_correct_word(original_name) ||
!tomoyo_correct_path(aggregated_name))
return -EINVAL;
e.original_name = tomoyo_get_name(original_name);
e.aggregated_name = tomoyo_get_name(aggregated_name);
if (!e.original_name || !e.aggregated_name ||
e.aggregated_name->is_patterned) /* No patterns allowed. */
goto out;
param->list = &tomoyo_policy_list[TOMOYO_ID_AGGREGATOR];
error = tomoyo_update_policy(&e.head, sizeof(e), param,
tomoyo_same_aggregator);
out:
tomoyo_put_name(e.original_name);
tomoyo_put_name(e.aggregated_name);
return error;
}
/**
* tomoyo_assign_domain - Create a domain.
*
* @domainname: The name of domain.
* @profile: Profile number to assign if the domain was newly created.
*
* Returns pointer to "struct tomoyo_domain_info" on success, NULL otherwise.
*
* Caller holds tomoyo_read_lock().
*/
struct tomoyo_domain_info *tomoyo_assign_domain(const char *domainname,
const u8 profile)
{
struct tomoyo_domain_info *entry;
struct tomoyo_domain_info *domain = NULL;
const struct tomoyo_path_info *saved_domainname;
bool found = false;
if (!tomoyo_correct_domain(domainname))
return NULL;
saved_domainname = tomoyo_get_name(domainname);
if (!saved_domainname)
return NULL;
entry = kzalloc(sizeof(*entry), GFP_NOFS);
if (mutex_lock_interruptible(&tomoyo_policy_lock))
goto out;
list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
if (domain->is_deleted ||
tomoyo_pathcmp(saved_domainname, domain->domainname))
continue;
found = true;
break;
}
if (!found && tomoyo_memory_ok(entry)) {
INIT_LIST_HEAD(&entry->acl_info_list);
entry->domainname = saved_domainname;
saved_domainname = NULL;
entry->profile = profile;
list_add_tail_rcu(&entry->list, &tomoyo_domain_list);
domain = entry;
entry = NULL;
found = true;
}
mutex_unlock(&tomoyo_policy_lock);
out:
tomoyo_put_name(saved_domainname);
kfree(entry);
return found ? domain : NULL;
}
/**
* tomoyo_find_next_domain - Find a domain.
*
* @bprm: Pointer to "struct linux_binprm".
*
* Returns 0 on success, negative value otherwise.
*
* Caller holds tomoyo_read_lock().
*/
int tomoyo_find_next_domain(struct linux_binprm *bprm)
{
struct tomoyo_request_info r;
char *tmp = kzalloc(TOMOYO_EXEC_TMPSIZE, GFP_NOFS);
struct tomoyo_domain_info *old_domain = tomoyo_domain();
struct tomoyo_domain_info *domain = NULL;
const char *original_name = bprm->filename;
u8 mode;
bool is_enforce;
int retval = -ENOMEM;
bool need_kfree = false;
struct tomoyo_path_info rn = { }; /* real name */
mode = tomoyo_init_request_info(&r, NULL, TOMOYO_MAC_FILE_EXECUTE);
is_enforce = (mode == TOMOYO_CONFIG_ENFORCING);
if (!tmp)
goto out;
retry:
if (need_kfree) {
kfree(rn.name);
need_kfree = false;
}
/* Get symlink's pathname of program. */
retval = -ENOENT;
rn.name = tomoyo_realpath_nofollow(original_name);
if (!rn.name)
goto out;
tomoyo_fill_path_info(&rn);
need_kfree = true;
/* Check 'aggregator' directive. */
{
struct tomoyo_aggregator *ptr;
list_for_each_entry_rcu(ptr, &tomoyo_policy_list
[TOMOYO_ID_AGGREGATOR], head.list) {
if (ptr->head.is_deleted ||
!tomoyo_path_matches_pattern(&rn,
ptr->original_name))
continue;
kfree(rn.name);
need_kfree = false;
/* This is OK because it is read only. */
rn = *ptr->aggregated_name;
break;
}
}
/* Check execute permission. */
retval = tomoyo_path_permission(&r, TOMOYO_TYPE_EXECUTE, &rn);
if (retval == TOMOYO_RETRY_REQUEST)
goto retry;
if (retval < 0)
goto out;
/*
* To be able to specify domainnames with wildcards, use the
* pathname specified in the policy (which may contain
* wildcard) rather than the pathname passed to execve()
* (which never contains wildcard).
*/
if (r.param.path.matched_path) {
if (need_kfree)
kfree(rn.name);
need_kfree = false;
/* This is OK because it is read only. */
rn = *r.param.path.matched_path;
}
/* Calculate domain to transit to. */
switch (tomoyo_transition_type(old_domain->domainname, &rn)) {
case TOMOYO_TRANSITION_CONTROL_INITIALIZE:
/* Transit to the child of tomoyo_kernel_domain domain. */
snprintf(tmp, TOMOYO_EXEC_TMPSIZE - 1, TOMOYO_ROOT_NAME " "
"%s", rn.name);
break;
case TOMOYO_TRANSITION_CONTROL_KEEP:
/* Keep current domain. */
domain = old_domain;
break;
default:
if (old_domain == &tomoyo_kernel_domain &&
!tomoyo_policy_loaded) {
/*
* Needn't to transit from kernel domain before
* starting /sbin/init. But transit from kernel domain
* if executing initializers because they might start
* before /sbin/init.
*/
domain = old_domain;
} else {
/* Normal domain transition. */
snprintf(tmp, TOMOYO_EXEC_TMPSIZE - 1, "%s %s",
old_domain->domainname->name, rn.name);
}
break;
}
if (domain || strlen(tmp) >= TOMOYO_EXEC_TMPSIZE - 10)
goto done;
domain = tomoyo_find_domain(tmp);
if (!domain)
domain = tomoyo_assign_domain(tmp, old_domain->profile);
done:
if (domain)
goto out;
printk(KERN_WARNING "TOMOYO-ERROR: Domain '%s' not defined.\n", tmp);
if (is_enforce)
retval = -EPERM;
else
old_domain->transition_failed = true;
out:
if (!domain)
domain = old_domain;
/* Update reference count on "struct tomoyo_domain_info". */
atomic_inc(&domain->users);
bprm->cred->security = domain;
if (need_kfree)
kfree(rn.name);
kfree(tmp);
return retval;
}