// SPDX-License-Identifier: GPL-2.0
/*
* security/tomoyo/domain.c
*
* Copyright (C) 2005-2011 NTT DATA CORPORATION
*/
#include "common.h"
#include <linux/binfmts.h>
#include <linux/slab.h>
#include <linux/rculist.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,
srcu_read_lock_held(&tomoyo_ss)) {
if (entry->is_deleted == TOMOYO_GC_IN_PROGRESS)
continue;
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 && a->cond == b->cond;
}
/**
* 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 (param->data[0]) {
new_entry->cond = tomoyo_get_condition(param);
if (!new_entry->cond)
return -EINVAL;
/*
* Domain transition preference is allowed for only
* "file execute" entries.
*/
if (new_entry->cond->transit &&
!(new_entry->type == TOMOYO_TYPE_PATH_ACL &&
container_of(new_entry, struct tomoyo_path_acl, head)
->perm == 1 << TOMOYO_TYPE_EXECUTE))
goto out;
}
if (mutex_lock_interruptible(&tomoyo_policy_lock))
goto out;
list_for_each_entry_rcu(entry, list, list,
srcu_read_lock_held(&tomoyo_ss)) {
if (entry->is_deleted == TOMOYO_GC_IN_PROGRESS)
continue;
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);
out:
tomoyo_put_condition(new_entry->cond);
return error;
}
/**
* tomoyo_check_acl - Do permission check.
*
* @r: Pointer to "struct tomoyo_request_info".
* @check_entry: Callback function to check type specific parameters.
*
* Returns 0 on success, negative value otherwise.
*
* Caller holds tomoyo_read_lock().
*/
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;
const struct list_head *list = &domain->acl_info_list;
u16 i = 0;
retry:
list_for_each_entry_rcu(ptr, list, list,
srcu_read_lock_held(&tomoyo_ss)) {
if (ptr->is_deleted || ptr->type != r->param_type)
continue;
if (!check_entry(r, ptr))
continue;
if (!tomoyo_condition(r, ptr->cond))
continue;
r->matched_acl = ptr;
r->granted = true;
return;
}
for (; i < TOMOYO_MAX_ACL_GROUPS; i++) {
if (!test_bit(i, domain->group))
continue;
list = &domain->ns->acl_group[i++];
goto retry;
}
r->granted = false;
}
/* The list for "struct tomoyo_domain_info". */
LIST_HEAD(tomoyo_domain_list);
/**
* tomoyo_last_word - Get last component of a domainname.
*
* @name: 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 && strcmp(program, "any")) {
if (!tomoyo_correct_path(program))
return -EINVAL;
e.program = tomoyo_get_name(program);
if (!e.program)
goto out;
}
if (domainname && strcmp(domainname, "any")) {
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 = ¶m->ns->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_scan_transition - Try to find specific domain transition type.
*
* @list: Pointer to "struct list_head".
* @domainname: The name of current domain.
* @program: The name of requested program.
* @last_name: The last component of @domainname.
* @type: One of values in "enum tomoyo_transition_type".
*
* Returns true if found one, false otherwise.
*
* Caller holds tomoyo_read_lock().
*/
static inline bool tomoyo_scan_transition
(const struct list_head *list, const struct tomoyo_path_info *domainname,
const struct tomoyo_path_info *program, const char *last_name,
const enum tomoyo_transition_type type)
{
const struct tomoyo_transition_control *ptr;
list_for_each_entry_rcu(ptr, list, head.list,
srcu_read_lock_held(&tomoyo_ss)) {
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;
return true;
}
return false;
}
/**
* tomoyo_transition_type - Get domain transition type.
*
* @ns: Pointer to "struct tomoyo_policy_namespace".
* @domainname: The name of current domain.
* @program: The name of requested program.
*
* Returns TOMOYO_TRANSITION_CONTROL_TRANSIT if executing @program causes
* domain transition across namespaces, TOMOYO_TRANSITION_CONTROL_INITIALIZE if
* executing @program reinitializes domain transition within that namespace,
* TOMOYO_TRANSITION_CONTROL_KEEP if executing @program stays at @domainname ,
* others otherwise.
*
* Caller holds tomoyo_read_lock().
*/
static enum tomoyo_transition_type tomoyo_transition_type
(const struct tomoyo_policy_namespace *ns,
const struct tomoyo_path_info *domainname,
const struct tomoyo_path_info *program)
{
const char *last_name = tomoyo_last_word(domainname->name);
enum tomoyo_transition_type type = TOMOYO_TRANSITION_CONTROL_NO_RESET;
while (type < TOMOYO_MAX_TRANSITION_TYPE) {
const struct list_head * const list =
&ns->policy_list[TOMOYO_ID_TRANSITION_CONTROL];
if (!tomoyo_scan_transition(list, domainname, program,
last_name, type)) {
type++;
continue;
}
if (type != TOMOYO_TRANSITION_CONTROL_NO_RESET &&
type != TOMOYO_TRANSITION_CONTROL_NO_INITIALIZE)
break;
/*
* Do not check for reset_domain if no_reset_domain matched.
* Do not check for initialize_domain if no_initialize_domain
* matched.
*/
type++;
type++;
}
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 = ¶m->ns->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_find_namespace - Find specified namespace.
*
* @name: Name of namespace to find.
* @len: Length of @name.
*
* Returns pointer to "struct tomoyo_policy_namespace" if found,
* NULL otherwise.
*
* Caller holds tomoyo_read_lock().
*/
static struct tomoyo_policy_namespace *tomoyo_find_namespace
(const char *name, const unsigned int len)
{
struct tomoyo_policy_namespace *ns;
list_for_each_entry(ns, &tomoyo_namespace_list, namespace_list) {
if (strncmp(name, ns->name, len) ||
(name[len] && name[len] != ' '))
continue;
return ns;
}
return NULL;
}
/**
* tomoyo_assign_namespace - Create a new namespace.
*
* @domainname: Name of namespace to create.
*
* Returns pointer to "struct tomoyo_policy_namespace" on success,
* NULL otherwise.
*
* Caller holds tomoyo_read_lock().
*/
struct tomoyo_policy_namespace *tomoyo_assign_namespace(const char *domainname)
{
struct tomoyo_policy_namespace *ptr;
struct tomoyo_policy_namespace *entry;
const char *cp = domainname;
unsigned int len = 0;
while (*cp && *cp++ != ' ')
len++;
ptr = tomoyo_find_namespace(domainname, len);
if (ptr)
return ptr;
if (len >= TOMOYO_EXEC_TMPSIZE - 10 || !tomoyo_domain_def(domainname))
return NULL;
entry = kzalloc(sizeof(*entry) + len + 1, GFP_NOFS | __GFP_NOWARN);
if (mutex_lock_interruptible(&tomoyo_policy_lock))
goto out;
ptr = tomoyo_find_namespace(domainname, len);
if (!ptr && tomoyo_memory_ok(entry)) {
char *name = (char *) (entry + 1);
ptr = entry;
memmove(name, domainname, len);
name[len] = '\0';
entry->name = name;
tomoyo_init_policy_namespace(entry);
entry = NULL;
}
mutex_unlock(&tomoyo_policy_lock);
out:
kfree(entry);
return ptr;
}
/**
* tomoyo_namespace_jump - Check for namespace jump.
*
* @domainname: Name of domain.
*
* Returns true if namespace differs, false otherwise.
*/
static bool tomoyo_namespace_jump(const char *domainname)
{
const char *namespace = tomoyo_current_namespace()->name;
const int len = strlen(namespace);
return strncmp(domainname, namespace, len) ||
(domainname[len] && domainname[len] != ' ');
}
/**
* tomoyo_assign_domain - Create a domain or a namespace.
*
* @domainname: The name of domain.
* @transit: True if transit to domain found or 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 bool transit)
{
struct tomoyo_domain_info e = { };
struct tomoyo_domain_info *entry = tomoyo_find_domain(domainname);
bool created = false;
if (entry) {
if (transit) {
/*
* Since namespace is created at runtime, profiles may
* not be created by the moment the process transits to
* that domain. Do not perform domain transition if
* profile for that domain is not yet created.
*/
if (tomoyo_policy_loaded &&
!entry->ns->profile_ptr[entry->profile])
return NULL;
}
return entry;
}
/* Requested domain does not exist. */
/* Don't create requested domain if domainname is invalid. */
if (strlen(domainname) >= TOMOYO_EXEC_TMPSIZE - 10 ||
!tomoyo_correct_domain(domainname))
return NULL;
/*
* Since definition of profiles and acl_groups may differ across
* namespaces, do not inherit "use_profile" and "use_group" settings
* by automatically creating requested domain upon domain transition.
*/
if (transit && tomoyo_namespace_jump(domainname))
return NULL;
e.ns = tomoyo_assign_namespace(domainname);
if (!e.ns)
return NULL;
/*
* "use_profile" and "use_group" settings for automatically created
* domains are inherited from current domain. These are 0 for manually
* created domains.
*/
if (transit) {
const struct tomoyo_domain_info *domain = tomoyo_domain();
e.profile = domain->profile;
memcpy(e.group, domain->group, sizeof(e.group));
}
e.domainname = tomoyo_get_name(domainname);
if (!e.domainname)
return NULL;
if (mutex_lock_interruptible(&tomoyo_policy_lock))
goto out;
entry = tomoyo_find_domain(domainname);
if (!entry) {
entry = tomoyo_commit_ok(&e, sizeof(e));
if (entry) {
INIT_LIST_HEAD(&entry->acl_info_list);
list_add_tail_rcu(&entry->list, &tomoyo_domain_list);
created = true;
}
}
mutex_unlock(&tomoyo_policy_lock);
out:
tomoyo_put_name(e.domainname);
if (entry && transit) {
if (created) {
struct tomoyo_request_info r;
int i;
tomoyo_init_request_info(&r, entry,
TOMOYO_MAC_FILE_EXECUTE);
r.granted = false;
tomoyo_write_log(&r, "use_profile %u\n",
entry->profile);
for (i = 0; i < TOMOYO_MAX_ACL_GROUPS; i++)
if (test_bit(i, entry->group))
tomoyo_write_log(&r, "use_group %u\n",
i);
tomoyo_update_stat(TOMOYO_STAT_POLICY_UPDATES);
}
}
return entry;
}
/**
* tomoyo_environ - Check permission for environment variable names.
*
* @ee: Pointer to "struct tomoyo_execve".
*
* Returns 0 on success, negative value otherwise.
*/
static int tomoyo_environ(struct tomoyo_execve *ee)
{
struct tomoyo_request_info *r = &ee->r;
struct linux_binprm *bprm = ee->bprm;
/* env_page.data is allocated by tomoyo_dump_page(). */
struct tomoyo_page_dump env_page = { };
char *arg_ptr; /* Size is TOMOYO_EXEC_TMPSIZE bytes */
int arg_len = 0;
unsigned long pos = bprm->p;
int offset = pos % PAGE_SIZE;
int argv_count = bprm->argc;
int envp_count = bprm->envc;
int error = -ENOMEM;
ee->r.type = TOMOYO_MAC_ENVIRON;
ee->r.profile = r->domain->profile;
ee->r.mode = tomoyo_get_mode(r->domain->ns, ee->r.profile,
TOMOYO_MAC_ENVIRON);
if (!r->mode || !envp_count)
return 0;
arg_ptr = kzalloc(TOMOYO_EXEC_TMPSIZE, GFP_NOFS);
if (!arg_ptr)
goto out;
while (error == -ENOMEM) {
if (!tomoyo_dump_page(bprm, pos, &env_page))
goto out;
pos += PAGE_SIZE - offset;
/* Read. */
while (argv_count && offset < PAGE_SIZE) {
if (!env_page.data[offset++])
argv_count--;
}
if (argv_count) {
offset = 0;
continue;
}
while (offset < PAGE_SIZE) {
const unsigned char c = env_page.data[offset++];
if (c && arg_len < TOMOYO_EXEC_TMPSIZE - 10) {
if (c == '=') {
arg_ptr[arg_len++] = '\0';
} else if (c == '\\') {
arg_ptr[arg_len++] = '\\';
arg_ptr[arg_len++] = '\\';
} else if (c > ' ' && c < 127) {
arg_ptr[arg_len++] = c;
} else {
arg_ptr[arg_len++] = '\\';
arg_ptr[arg_len++] = (c >> 6) + '0';
arg_ptr[arg_len++]
= ((c >> 3) & 7) + '0';
arg_ptr[arg_len++] = (c & 7) + '0';
}
} else {
arg_ptr[arg_len] = '\0';
}
if (c)
continue;
if (tomoyo_env_perm(r, arg_ptr)) {
error = -EPERM;
break;
}
if (!--envp_count) {
error = 0;
break;
}
arg_len = 0;
}
offset = 0;
}
out:
if (r->mode != TOMOYO_CONFIG_ENFORCING)
error = 0;
kfree(env_page.data);
kfree(arg_ptr);
return error;
}
/**
* 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_domain_info *old_domain = tomoyo_domain();
struct tomoyo_domain_info *domain = NULL;
const char *original_name = bprm->filename;
int retval = -ENOMEM;
bool reject_on_transition_failure = false;
const struct tomoyo_path_info *candidate;
struct tomoyo_path_info exename;
struct tomoyo_execve *ee = kzalloc(sizeof(*ee), GFP_NOFS);
if (!ee)
return -ENOMEM;
ee->tmp = kzalloc(TOMOYO_EXEC_TMPSIZE, GFP_NOFS);
if (!ee->tmp) {
kfree(ee);
return -ENOMEM;
}
/* ee->dump->data is allocated by tomoyo_dump_page(). */
tomoyo_init_request_info(&ee->r, NULL, TOMOYO_MAC_FILE_EXECUTE);
ee->r.ee = ee;
ee->bprm = bprm;
ee->r.obj = &ee->obj;
ee->obj.path1 = bprm->file->f_path;
/* Get symlink's pathname of program. */
exename.name = tomoyo_realpath_nofollow(original_name);
if (!exename.name) {
/* Fallback to realpath if symlink's pathname does not exist. */
exename.name = tomoyo_realpath_from_path(&bprm->file->f_path);
if (!exename.name)
goto out;
}
tomoyo_fill_path_info(&exename);
retry:
/* Check 'aggregator' directive. */
{
struct tomoyo_aggregator *ptr;
struct list_head *list =
&old_domain->ns->policy_list[TOMOYO_ID_AGGREGATOR];
/* Check 'aggregator' directive. */
candidate = &exename;
list_for_each_entry_rcu(ptr, list, head.list,
srcu_read_lock_held(&tomoyo_ss)) {
if (ptr->head.is_deleted ||
!tomoyo_path_matches_pattern(&exename,
ptr->original_name))
continue;
candidate = ptr->aggregated_name;
break;
}
}
/* Check execute permission. */
retval = tomoyo_execute_permission(&ee->r, candidate);
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 (ee->r.param.path.matched_path)
candidate = ee->r.param.path.matched_path;
/*
* Check for domain transition preference if "file execute" matched.
* If preference is given, make execve() fail if domain transition
* has failed, for domain transition preference should be used with
* destination domain defined.
*/
if (ee->transition) {
const char *domainname = ee->transition->name;
reject_on_transition_failure = true;
if (!strcmp(domainname, "keep"))
goto force_keep_domain;
if (!strcmp(domainname, "child"))
goto force_child_domain;
if (!strcmp(domainname, "reset"))
goto force_reset_domain;
if (!strcmp(domainname, "initialize"))
goto force_initialize_domain;
if (!strcmp(domainname, "parent")) {
char *cp;
strscpy(ee->tmp, old_domain->domainname->name, TOMOYO_EXEC_TMPSIZE);
cp = strrchr(ee->tmp, ' ');
if (cp)
*cp = '\0';
} else if (*domainname == '<')
strscpy(ee->tmp, domainname, TOMOYO_EXEC_TMPSIZE);
else
snprintf(ee->tmp, TOMOYO_EXEC_TMPSIZE - 1, "%s %s",
old_domain->domainname->name, domainname);
goto force_jump_domain;
}
/*
* No domain transition preference specified.
* Calculate domain to transit to.
*/
switch (tomoyo_transition_type(old_domain->ns, old_domain->domainname,
candidate)) {
case TOMOYO_TRANSITION_CONTROL_RESET:
force_reset_domain:
/* Transit to the root of specified namespace. */
snprintf(ee->tmp, TOMOYO_EXEC_TMPSIZE - 1, "<%s>",
candidate->name);
/*
* Make execve() fail if domain transition across namespaces
* has failed.
*/
reject_on_transition_failure = true;
break;
case TOMOYO_TRANSITION_CONTROL_INITIALIZE:
force_initialize_domain:
/* Transit to the child of current namespace's root. */
snprintf(ee->tmp, TOMOYO_EXEC_TMPSIZE - 1, "%s %s",
old_domain->ns->name, candidate->name);
break;
case TOMOYO_TRANSITION_CONTROL_KEEP:
force_keep_domain:
/* 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;
break;
}
force_child_domain:
/* Normal domain transition. */
snprintf(ee->tmp, TOMOYO_EXEC_TMPSIZE - 1, "%s %s",
old_domain->domainname->name, candidate->name);
break;
}
force_jump_domain:
if (!domain)
domain = tomoyo_assign_domain(ee->tmp, true);
if (domain)
retval = 0;
else if (reject_on_transition_failure) {
pr_warn("ERROR: Domain '%s' not ready.\n", ee->tmp);
retval = -ENOMEM;
} else if (ee->r.mode == TOMOYO_CONFIG_ENFORCING)
retval = -ENOMEM;
else {
retval = 0;
if (!old_domain->flags[TOMOYO_DIF_TRANSITION_FAILED]) {
old_domain->flags[TOMOYO_DIF_TRANSITION_FAILED] = true;
ee->r.granted = false;
tomoyo_write_log(&ee->r, "%s", tomoyo_dif
[TOMOYO_DIF_TRANSITION_FAILED]);
pr_warn("ERROR: Domain '%s' not defined.\n", ee->tmp);
}
}
out:
if (!domain)
domain = old_domain;
/* Update reference count on "struct tomoyo_domain_info". */
{
struct tomoyo_task *s = tomoyo_task(current);
s->old_domain_info = s->domain_info;
s->domain_info = domain;
atomic_inc(&domain->users);
}
kfree(exename.name);
if (!retval) {
ee->r.domain = domain;
retval = tomoyo_environ(ee);
}
kfree(ee->tmp);
kfree(ee->dump.data);
kfree(ee);
return retval;
}
/**
* tomoyo_dump_page - Dump a page to buffer.
*
* @bprm: Pointer to "struct linux_binprm".
* @pos: Location to dump.
* @dump: Pointer to "struct tomoyo_page_dump".
*
* Returns true on success, false otherwise.
*/
bool tomoyo_dump_page(struct linux_binprm *bprm, unsigned long pos,
struct tomoyo_page_dump *dump)
{
struct page *page;
#ifdef CONFIG_MMU
int ret;
#endif
/* dump->data is released by tomoyo_find_next_domain(). */
if (!dump->data) {
dump->data = kzalloc(PAGE_SIZE, GFP_NOFS);
if (!dump->data)
return false;
}
/* Same with get_arg_page(bprm, pos, 0) in fs/exec.c */
#ifdef CONFIG_MMU
/*
* This is called at execve() time in order to dig around
* in the argv/environment of the new proceess
* (represented by bprm).
*/
mmap_read_lock(bprm->mm);
ret = get_user_pages_remote(bprm->mm, pos, 1,
FOLL_FORCE, &page, NULL);
mmap_read_unlock(bprm->mm);
if (ret <= 0)
return false;
#else
page = bprm->page[pos / PAGE_SIZE];
#endif
if (page != dump->page) {
const unsigned int offset = pos % PAGE_SIZE;
/*
* Maybe kmap()/kunmap() should be used here.
* But remove_arg_zero() uses kmap_atomic()/kunmap_atomic().
* So do I.
*/
char *kaddr = kmap_atomic(page);
dump->page = page;
memcpy(dump->data + offset, kaddr + offset,
PAGE_SIZE - offset);
kunmap_atomic(kaddr);
}
/* Same with put_arg_page(page) in fs/exec.c */
#ifdef CONFIG_MMU
put_page(page);
#endif
return true;
}
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