Linux-2.6.33.2/security/tomoyo/domain.c
/*
* security/tomoyo/domain.c
*
* Implementation of the Domain-Based Mandatory Access Control.
*
* Copyright (C) 2005-2009 NTT DATA CORPORATION
*
* Version: 2.2.0 2009/04/01
*
*/
#include "common.h"
#include "tomoyo.h"
#include "realpath.h"
#include <linux/binfmts.h>
/* Variables definitions.*/
/* The initial domain. */
struct tomoyo_domain_info tomoyo_kernel_domain;
/*
* tomoyo_domain_list is used for holding list of domains.
* The ->acl_info_list of "struct tomoyo_domain_info" is used for holding
* permissions (e.g. "allow_read /lib/libc-2.5.so") given to each domain.
*
* An entry is added by
*
* # ( echo "<kernel>"; echo "allow_execute /sbin/init" ) > \
* /sys/kernel/security/tomoyo/domain_policy
*
* and is deleted by
*
* # ( echo "<kernel>"; echo "delete allow_execute /sbin/init" ) > \
* /sys/kernel/security/tomoyo/domain_policy
*
* and all entries are retrieved by
*
* # cat /sys/kernel/security/tomoyo/domain_policy
*
* A domain is added by
*
* # echo "<kernel>" > /sys/kernel/security/tomoyo/domain_policy
*
* and is deleted by
*
* # echo "delete <kernel>" > /sys/kernel/security/tomoyo/domain_policy
*
* and all domains are retrieved by
*
* # grep '^<kernel>' /sys/kernel/security/tomoyo/domain_policy
*
* Normally, a domainname is monotonically getting longer because a domainname
* which the process will belong to if an execve() operation succeeds is
* defined as a concatenation of "current domainname" + "pathname passed to
* execve()".
* See tomoyo_domain_initializer_list and tomoyo_domain_keeper_list for
* exceptions.
*/
LIST_HEAD(tomoyo_domain_list);
DECLARE_RWSEM(tomoyo_domain_list_lock);
/*
* tomoyo_domain_initializer_entry is a structure which is used for holding
* "initialize_domain" and "no_initialize_domain" entries.
* It has following fields.
*
* (1) "list" which is linked to tomoyo_domain_initializer_list .
* (2) "domainname" which is "a domainname" or "the last component of a
* domainname". This field is NULL if "from" clause is not specified.
* (3) "program" which is a program's pathname.
* (4) "is_deleted" is a bool which is true if marked as deleted, false
* otherwise.
* (5) "is_not" is a bool which is true if "no_initialize_domain", false
* otherwise.
* (6) "is_last_name" is a bool which is true if "domainname" is "the last
* component of a domainname", false otherwise.
*/
struct tomoyo_domain_initializer_entry {
struct list_head list;
const struct tomoyo_path_info *domainname; /* This may be NULL */
const struct tomoyo_path_info *program;
bool is_deleted;
bool is_not; /* True if this entry is "no_initialize_domain". */
/* True if the domainname is tomoyo_get_last_name(). */
bool is_last_name;
};
/*
* tomoyo_domain_keeper_entry is a structure which is used for holding
* "keep_domain" and "no_keep_domain" entries.
* It has following fields.
*
* (1) "list" which is linked to tomoyo_domain_keeper_list .
* (2) "domainname" which is "a domainname" or "the last component of a
* domainname".
* (3) "program" which is a program's pathname.
* This field is NULL if "from" clause is not specified.
* (4) "is_deleted" is a bool which is true if marked as deleted, false
* otherwise.
* (5) "is_not" is a bool which is true if "no_initialize_domain", false
* otherwise.
* (6) "is_last_name" is a bool which is true if "domainname" is "the last
* component of a domainname", false otherwise.
*/
struct tomoyo_domain_keeper_entry {
struct list_head list;
const struct tomoyo_path_info *domainname;
const struct tomoyo_path_info *program; /* This may be NULL */
bool is_deleted;
bool is_not; /* True if this entry is "no_keep_domain". */
/* True if the domainname is tomoyo_get_last_name(). */
bool is_last_name;
};
/*
* tomoyo_alias_entry is a structure which is used for holding "alias" entries.
* It has following fields.
*
* (1) "list" which is linked to tomoyo_alias_list .
* (2) "original_name" which is a dereferenced pathname.
* (3) "aliased_name" which is a symlink's pathname.
* (4) "is_deleted" is a bool which is true if marked as deleted, false
* otherwise.
*/
struct tomoyo_alias_entry {
struct list_head list;
const struct tomoyo_path_info *original_name;
const struct tomoyo_path_info *aliased_name;
bool is_deleted;
};
/**
* tomoyo_set_domain_flag - Set or clear domain's attribute flags.
*
* @domain: Pointer to "struct tomoyo_domain_info".
* @is_delete: True if it is a delete request.
* @flags: Flags to set or clear.
*
* Returns nothing.
*/
void tomoyo_set_domain_flag(struct tomoyo_domain_info *domain,
const bool is_delete, const u8 flags)
{
/* We need to serialize because this is bitfield operation. */
static DEFINE_SPINLOCK(lock);
spin_lock(&lock);
if (!is_delete)
domain->flags |= flags;
else
domain->flags &= ~flags;
spin_unlock(&lock);
}
/**
* tomoyo_get_last_name - Get last component of a domainname.
*
* @domain: Pointer to "struct tomoyo_domain_info".
*
* Returns the last component of the domainname.
*/
const char *tomoyo_get_last_name(const struct tomoyo_domain_info *domain)
{
const char *cp0 = domain->domainname->name;
const char *cp1 = strrchr(cp0, ' ');
if (cp1)
return cp1 + 1;
return cp0;
}
/*
* tomoyo_domain_initializer_list is used for holding list of programs which
* triggers reinitialization of domainname. Normally, a domainname is
* monotonically getting longer. But sometimes, we restart daemon programs.
* It would be convenient for us that "a daemon started upon system boot" and
* "the daemon restarted from console" belong to the same domain. Thus, TOMOYO
* provides a way to shorten domainnames.
*
* An entry is added by
*
* # echo 'initialize_domain /usr/sbin/httpd' > \
* /sys/kernel/security/tomoyo/exception_policy
*
* and is deleted by
*
* # echo 'delete initialize_domain /usr/sbin/httpd' > \
* /sys/kernel/security/tomoyo/exception_policy
*
* and all entries are retrieved by
*
* # grep ^initialize_domain /sys/kernel/security/tomoyo/exception_policy
*
* In the example above, /usr/sbin/httpd will belong to
* "<kernel> /usr/sbin/httpd" domain.
*
* You may specify a domainname using "from" keyword.
* "initialize_domain /usr/sbin/httpd from <kernel> /etc/rc.d/init.d/httpd"
* will cause "/usr/sbin/httpd" executed from "<kernel> /etc/rc.d/init.d/httpd"
* domain to belong to "<kernel> /usr/sbin/httpd" domain.
*
* You may add "no_" prefix to "initialize_domain".
* "initialize_domain /usr/sbin/httpd" and
* "no_initialize_domain /usr/sbin/httpd from <kernel> /etc/rc.d/init.d/httpd"
* will cause "/usr/sbin/httpd" to belong to "<kernel> /usr/sbin/httpd" domain
* unless executed from "<kernel> /etc/rc.d/init.d/httpd" domain.
*/
static LIST_HEAD(tomoyo_domain_initializer_list);
static DECLARE_RWSEM(tomoyo_domain_initializer_list_lock);
/**
* tomoyo_update_domain_initializer_entry - Update "struct tomoyo_domain_initializer_entry" list.
*
* @domainname: The name of domain. May be NULL.
* @program: The name of program.
* @is_not: True if it is "no_initialize_domain" entry.
* @is_delete: True if it is a delete request.
*
* Returns 0 on success, negative value otherwise.
*/
static int tomoyo_update_domain_initializer_entry(const char *domainname,
const char *program,
const bool is_not,
const bool is_delete)
{
struct tomoyo_domain_initializer_entry *new_entry;
struct tomoyo_domain_initializer_entry *ptr;
const struct tomoyo_path_info *saved_program;
const struct tomoyo_path_info *saved_domainname = NULL;
int error = -ENOMEM;
bool is_last_name = false;
if (!tomoyo_is_correct_path(program, 1, -1, -1, __func__))
return -EINVAL; /* No patterns allowed. */
if (domainname) {
if (!tomoyo_is_domain_def(domainname) &&
tomoyo_is_correct_path(domainname, 1, -1, -1, __func__))
is_last_name = true;
else if (!tomoyo_is_correct_domain(domainname, __func__))
return -EINVAL;
saved_domainname = tomoyo_save_name(domainname);
if (!saved_domainname)
return -ENOMEM;
}
saved_program = tomoyo_save_name(program);
if (!saved_program)
return -ENOMEM;
down_write(&tomoyo_domain_initializer_list_lock);
list_for_each_entry(ptr, &tomoyo_domain_initializer_list, list) {
if (ptr->is_not != is_not ||
ptr->domainname != saved_domainname ||
ptr->program != saved_program)
continue;
ptr->is_deleted = is_delete;
error = 0;
goto out;
}
if (is_delete) {
error = -ENOENT;
goto out;
}
new_entry = tomoyo_alloc_element(sizeof(*new_entry));
if (!new_entry)
goto out;
new_entry->domainname = saved_domainname;
new_entry->program = saved_program;
new_entry->is_not = is_not;
new_entry->is_last_name = is_last_name;
list_add_tail(&new_entry->list, &tomoyo_domain_initializer_list);
error = 0;
out:
up_write(&tomoyo_domain_initializer_list_lock);
return error;
}
/**
* tomoyo_read_domain_initializer_policy - Read "struct tomoyo_domain_initializer_entry" list.
*
* @head: Pointer to "struct tomoyo_io_buffer".
*
* Returns true on success, false otherwise.
*/
bool tomoyo_read_domain_initializer_policy(struct tomoyo_io_buffer *head)
{
struct list_head *pos;
bool done = true;
down_read(&tomoyo_domain_initializer_list_lock);
list_for_each_cookie(pos, head->read_var2,
&tomoyo_domain_initializer_list) {
const char *no;
const char *from = "";
const char *domain = "";
struct tomoyo_domain_initializer_entry *ptr;
ptr = list_entry(pos, struct tomoyo_domain_initializer_entry,
list);
if (ptr->is_deleted)
continue;
no = ptr->is_not ? "no_" : "";
if (ptr->domainname) {
from = " from ";
domain = ptr->domainname->name;
}
done = tomoyo_io_printf(head,
"%s" TOMOYO_KEYWORD_INITIALIZE_DOMAIN
"%s%s%s\n", no, ptr->program->name,
from, domain);
if (!done)
break;
}
up_read(&tomoyo_domain_initializer_list_lock);
return done;
}
/**
* tomoyo_write_domain_initializer_policy - Write "struct tomoyo_domain_initializer_entry" list.
*
* @data: String to parse.
* @is_not: True if it is "no_initialize_domain" entry.
* @is_delete: True if it is a delete request.
*
* Returns 0 on success, negative value otherwise.
*/
int tomoyo_write_domain_initializer_policy(char *data, const bool is_not,
const bool is_delete)
{
char *cp = strstr(data, " from ");
if (cp) {
*cp = '\0';
return tomoyo_update_domain_initializer_entry(cp + 6, data,
is_not,
is_delete);
}
return tomoyo_update_domain_initializer_entry(NULL, data, is_not,
is_delete);
}
/**
* tomoyo_is_domain_initializer - Check whether the given program causes domainname reinitialization.
*
* @domainname: The name of domain.
* @program: The name of program.
* @last_name: The last component of @domainname.
*
* Returns true if executing @program reinitializes domain transition,
* false otherwise.
*/
static bool tomoyo_is_domain_initializer(const struct tomoyo_path_info *
domainname,
const struct tomoyo_path_info *program,
const struct tomoyo_path_info *
last_name)
{
struct tomoyo_domain_initializer_entry *ptr;
bool flag = false;
down_read(&tomoyo_domain_initializer_list_lock);
list_for_each_entry(ptr, &tomoyo_domain_initializer_list, list) {
if (ptr->is_deleted)
continue;
if (ptr->domainname) {
if (!ptr->is_last_name) {
if (ptr->domainname != domainname)
continue;
} else {
if (tomoyo_pathcmp(ptr->domainname, last_name))
continue;
}
}
if (tomoyo_pathcmp(ptr->program, program))
continue;
if (ptr->is_not) {
flag = false;
break;
}
flag = true;
}
up_read(&tomoyo_domain_initializer_list_lock);
return flag;
}
/*
* tomoyo_domain_keeper_list is used for holding list of domainnames which
* suppresses domain transition. Normally, a domainname is monotonically
* getting longer. But sometimes, we want to suppress domain transition.
* It would be convenient for us that programs executed from a login session
* belong to the same domain. Thus, TOMOYO provides a way to suppress domain
* transition.
*
* An entry is added by
*
* # echo 'keep_domain <kernel> /usr/sbin/sshd /bin/bash' > \
* /sys/kernel/security/tomoyo/exception_policy
*
* and is deleted by
*
* # echo 'delete keep_domain <kernel> /usr/sbin/sshd /bin/bash' > \
* /sys/kernel/security/tomoyo/exception_policy
*
* and all entries are retrieved by
*
* # grep ^keep_domain /sys/kernel/security/tomoyo/exception_policy
*
* In the example above, any process which belongs to
* "<kernel> /usr/sbin/sshd /bin/bash" domain will remain in that domain,
* unless explicitly specified by "initialize_domain" or "no_keep_domain".
*
* You may specify a program using "from" keyword.
* "keep_domain /bin/pwd from <kernel> /usr/sbin/sshd /bin/bash"
* will cause "/bin/pwd" executed from "<kernel> /usr/sbin/sshd /bin/bash"
* domain to remain in "<kernel> /usr/sbin/sshd /bin/bash" domain.
*
* You may add "no_" prefix to "keep_domain".
* "keep_domain <kernel> /usr/sbin/sshd /bin/bash" and
* "no_keep_domain /usr/bin/passwd from <kernel> /usr/sbin/sshd /bin/bash" will
* cause "/usr/bin/passwd" to belong to
* "<kernel> /usr/sbin/sshd /bin/bash /usr/bin/passwd" domain, unless
* explicitly specified by "initialize_domain".
*/
static LIST_HEAD(tomoyo_domain_keeper_list);
static DECLARE_RWSEM(tomoyo_domain_keeper_list_lock);
/**
* tomoyo_update_domain_keeper_entry - Update "struct tomoyo_domain_keeper_entry" list.
*
* @domainname: The name of domain.
* @program: The name of program. May be NULL.
* @is_not: True if it is "no_keep_domain" entry.
* @is_delete: True if it is a delete request.
*
* Returns 0 on success, negative value otherwise.
*/
static int tomoyo_update_domain_keeper_entry(const char *domainname,
const char *program,
const bool is_not,
const bool is_delete)
{
struct tomoyo_domain_keeper_entry *new_entry;
struct tomoyo_domain_keeper_entry *ptr;
const struct tomoyo_path_info *saved_domainname;
const struct tomoyo_path_info *saved_program = NULL;
int error = -ENOMEM;
bool is_last_name = false;
if (!tomoyo_is_domain_def(domainname) &&
tomoyo_is_correct_path(domainname, 1, -1, -1, __func__))
is_last_name = true;
else if (!tomoyo_is_correct_domain(domainname, __func__))
return -EINVAL;
if (program) {
if (!tomoyo_is_correct_path(program, 1, -1, -1, __func__))
return -EINVAL;
saved_program = tomoyo_save_name(program);
if (!saved_program)
return -ENOMEM;
}
saved_domainname = tomoyo_save_name(domainname);
if (!saved_domainname)
return -ENOMEM;
down_write(&tomoyo_domain_keeper_list_lock);
list_for_each_entry(ptr, &tomoyo_domain_keeper_list, list) {
if (ptr->is_not != is_not ||
ptr->domainname != saved_domainname ||
ptr->program != saved_program)
continue;
ptr->is_deleted = is_delete;
error = 0;
goto out;
}
if (is_delete) {
error = -ENOENT;
goto out;
}
new_entry = tomoyo_alloc_element(sizeof(*new_entry));
if (!new_entry)
goto out;
new_entry->domainname = saved_domainname;
new_entry->program = saved_program;
new_entry->is_not = is_not;
new_entry->is_last_name = is_last_name;
list_add_tail(&new_entry->list, &tomoyo_domain_keeper_list);
error = 0;
out:
up_write(&tomoyo_domain_keeper_list_lock);
return error;
}
/**
* tomoyo_write_domain_keeper_policy - Write "struct tomoyo_domain_keeper_entry" list.
*
* @data: String to parse.
* @is_not: True if it is "no_keep_domain" entry.
* @is_delete: True if it is a delete request.
*
*/
int tomoyo_write_domain_keeper_policy(char *data, const bool is_not,
const bool is_delete)
{
char *cp = strstr(data, " from ");
if (cp) {
*cp = '\0';
return tomoyo_update_domain_keeper_entry(cp + 6, data, is_not,
is_delete);
}
return tomoyo_update_domain_keeper_entry(data, NULL, is_not, is_delete);
}
/**
* tomoyo_read_domain_keeper_policy - Read "struct tomoyo_domain_keeper_entry" list.
*
* @head: Pointer to "struct tomoyo_io_buffer".
*
* Returns true on success, false otherwise.
*/
bool tomoyo_read_domain_keeper_policy(struct tomoyo_io_buffer *head)
{
struct list_head *pos;
bool done = true;
down_read(&tomoyo_domain_keeper_list_lock);
list_for_each_cookie(pos, head->read_var2,
&tomoyo_domain_keeper_list) {
struct tomoyo_domain_keeper_entry *ptr;
const char *no;
const char *from = "";
const char *program = "";
ptr = list_entry(pos, struct tomoyo_domain_keeper_entry, list);
if (ptr->is_deleted)
continue;
no = ptr->is_not ? "no_" : "";
if (ptr->program) {
from = " from ";
program = ptr->program->name;
}
done = tomoyo_io_printf(head,
"%s" TOMOYO_KEYWORD_KEEP_DOMAIN
"%s%s%s\n", no, program, from,
ptr->domainname->name);
if (!done)
break;
}
up_read(&tomoyo_domain_keeper_list_lock);
return done;
}
/**
* tomoyo_is_domain_keeper - Check whether the given program causes domain transition suppression.
*
* @domainname: The name of domain.
* @program: The name of program.
* @last_name: The last component of @domainname.
*
* Returns true if executing @program supresses domain transition,
* false otherwise.
*/
static bool tomoyo_is_domain_keeper(const struct tomoyo_path_info *domainname,
const struct tomoyo_path_info *program,
const struct tomoyo_path_info *last_name)
{
struct tomoyo_domain_keeper_entry *ptr;
bool flag = false;
down_read(&tomoyo_domain_keeper_list_lock);
list_for_each_entry(ptr, &tomoyo_domain_keeper_list, list) {
if (ptr->is_deleted)
continue;
if (!ptr->is_last_name) {
if (ptr->domainname != domainname)
continue;
} else {
if (tomoyo_pathcmp(ptr->domainname, last_name))
continue;
}
if (ptr->program && tomoyo_pathcmp(ptr->program, program))
continue;
if (ptr->is_not) {
flag = false;
break;
}
flag = true;
}
up_read(&tomoyo_domain_keeper_list_lock);
return flag;
}
/*
* tomoyo_alias_list is used for holding list of symlink's pathnames which are
* allowed to be passed to an execve() request. Normally, the domainname which
* the current process will belong to after execve() succeeds is calculated
* using dereferenced pathnames. But some programs behave differently depending
* on the name passed to argv[0]. For busybox, calculating domainname using
* dereferenced pathnames will cause all programs in the busybox to belong to
* the same domain. Thus, TOMOYO provides a way to allow use of symlink's
* pathname for checking execve()'s permission and calculating domainname which
* the current process will belong to after execve() succeeds.
*
* An entry is added by
*
* # echo 'alias /bin/busybox /bin/cat' > \
* /sys/kernel/security/tomoyo/exception_policy
*
* and is deleted by
*
* # echo 'delete alias /bin/busybox /bin/cat' > \
* /sys/kernel/security/tomoyo/exception_policy
*
* and all entries are retrieved by
*
* # grep ^alias /sys/kernel/security/tomoyo/exception_policy
*
* In the example above, if /bin/cat is a symlink to /bin/busybox and execution
* of /bin/cat is requested, permission is checked for /bin/cat rather than
* /bin/busybox and domainname which the current process will belong to after
* execve() succeeds is calculated using /bin/cat rather than /bin/busybox .
*/
static LIST_HEAD(tomoyo_alias_list);
static DECLARE_RWSEM(tomoyo_alias_list_lock);
/**
* tomoyo_update_alias_entry - Update "struct tomoyo_alias_entry" list.
*
* @original_name: The original program's real name.
* @aliased_name: The symbolic program's symbolic link's name.
* @is_delete: True if it is a delete request.
*
* Returns 0 on success, negative value otherwise.
*/
static int tomoyo_update_alias_entry(const char *original_name,
const char *aliased_name,
const bool is_delete)
{
struct tomoyo_alias_entry *new_entry;
struct tomoyo_alias_entry *ptr;
const struct tomoyo_path_info *saved_original_name;
const struct tomoyo_path_info *saved_aliased_name;
int error = -ENOMEM;
if (!tomoyo_is_correct_path(original_name, 1, -1, -1, __func__) ||
!tomoyo_is_correct_path(aliased_name, 1, -1, -1, __func__))
return -EINVAL; /* No patterns allowed. */
saved_original_name = tomoyo_save_name(original_name);
saved_aliased_name = tomoyo_save_name(aliased_name);
if (!saved_original_name || !saved_aliased_name)
return -ENOMEM;
down_write(&tomoyo_alias_list_lock);
list_for_each_entry(ptr, &tomoyo_alias_list, list) {
if (ptr->original_name != saved_original_name ||
ptr->aliased_name != saved_aliased_name)
continue;
ptr->is_deleted = is_delete;
error = 0;
goto out;
}
if (is_delete) {
error = -ENOENT;
goto out;
}
new_entry = tomoyo_alloc_element(sizeof(*new_entry));
if (!new_entry)
goto out;
new_entry->original_name = saved_original_name;
new_entry->aliased_name = saved_aliased_name;
list_add_tail(&new_entry->list, &tomoyo_alias_list);
error = 0;
out:
up_write(&tomoyo_alias_list_lock);
return error;
}
/**
* tomoyo_read_alias_policy - Read "struct tomoyo_alias_entry" list.
*
* @head: Pointer to "struct tomoyo_io_buffer".
*
* Returns true on success, false otherwise.
*/
bool tomoyo_read_alias_policy(struct tomoyo_io_buffer *head)
{
struct list_head *pos;
bool done = true;
down_read(&tomoyo_alias_list_lock);
list_for_each_cookie(pos, head->read_var2, &tomoyo_alias_list) {
struct tomoyo_alias_entry *ptr;
ptr = list_entry(pos, struct tomoyo_alias_entry, list);
if (ptr->is_deleted)
continue;
done = tomoyo_io_printf(head, TOMOYO_KEYWORD_ALIAS "%s %s\n",
ptr->original_name->name,
ptr->aliased_name->name);
if (!done)
break;
}
up_read(&tomoyo_alias_list_lock);
return done;
}
/**
* tomoyo_write_alias_policy - Write "struct tomoyo_alias_entry" list.
*
* @data: String to parse.
* @is_delete: True if it is a delete request.
*
* Returns 0 on success, negative value otherwise.
*/
int tomoyo_write_alias_policy(char *data, const bool is_delete)
{
char *cp = strchr(data, ' ');
if (!cp)
return -EINVAL;
*cp++ = '\0';
return tomoyo_update_alias_entry(data, cp, is_delete);
}
/**
* tomoyo_find_or_assign_new_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.
*/
struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char *
domainname,
const u8 profile)
{
struct tomoyo_domain_info *domain = NULL;
const struct tomoyo_path_info *saved_domainname;
down_write(&tomoyo_domain_list_lock);
domain = tomoyo_find_domain(domainname);
if (domain)
goto out;
if (!tomoyo_is_correct_domain(domainname, __func__))
goto out;
saved_domainname = tomoyo_save_name(domainname);
if (!saved_domainname)
goto out;
/* Can I reuse memory of deleted domain? */
list_for_each_entry(domain, &tomoyo_domain_list, list) {
struct task_struct *p;
struct tomoyo_acl_info *ptr;
bool flag;
if (!domain->is_deleted ||
domain->domainname != saved_domainname)
continue;
flag = false;
read_lock(&tasklist_lock);
for_each_process(p) {
if (tomoyo_real_domain(p) != domain)
continue;
flag = true;
break;
}
read_unlock(&tasklist_lock);
if (flag)
continue;
list_for_each_entry(ptr, &domain->acl_info_list, list) {
ptr->type |= TOMOYO_ACL_DELETED;
}
tomoyo_set_domain_flag(domain, true, domain->flags);
domain->profile = profile;
domain->quota_warned = false;
mb(); /* Avoid out-of-order execution. */
domain->is_deleted = false;
goto out;
}
/* No memory reusable. Create using new memory. */
domain = tomoyo_alloc_element(sizeof(*domain));
if (domain) {
INIT_LIST_HEAD(&domain->acl_info_list);
domain->domainname = saved_domainname;
domain->profile = profile;
list_add_tail(&domain->list, &tomoyo_domain_list);
}
out:
up_write(&tomoyo_domain_list_lock);
return domain;
}
/**
* tomoyo_find_next_domain - Find a domain.
*
* @bprm: Pointer to "struct linux_binprm".
*
* Returns 0 on success, negative value otherwise.
*/
int tomoyo_find_next_domain(struct linux_binprm *bprm)
{
/*
* This function assumes that the size of buffer returned by
* tomoyo_realpath() = TOMOYO_MAX_PATHNAME_LEN.
*/
struct tomoyo_page_buffer *tmp = tomoyo_alloc(sizeof(*tmp));
struct tomoyo_domain_info *old_domain = tomoyo_domain();
struct tomoyo_domain_info *domain = NULL;
const char *old_domain_name = old_domain->domainname->name;
const char *original_name = bprm->filename;
char *new_domain_name = NULL;
char *real_program_name = NULL;
char *symlink_program_name = NULL;
const u8 mode = tomoyo_check_flags(old_domain, TOMOYO_MAC_FOR_FILE);
const bool is_enforce = (mode == 3);
int retval = -ENOMEM;
struct tomoyo_path_info r; /* real name */
struct tomoyo_path_info s; /* symlink name */
struct tomoyo_path_info l; /* last name */
static bool initialized;
if (!tmp)
goto out;
if (!initialized) {
/*
* Built-in initializers. This is needed because policies are
* not loaded until starting /sbin/init.
*/
tomoyo_update_domain_initializer_entry(NULL, "/sbin/hotplug",
false, false);
tomoyo_update_domain_initializer_entry(NULL, "/sbin/modprobe",
false, false);
initialized = true;
}
/* Get tomoyo_realpath of program. */
retval = -ENOENT;
/* I hope tomoyo_realpath() won't fail with -ENOMEM. */
real_program_name = tomoyo_realpath(original_name);
if (!real_program_name)
goto out;
/* Get tomoyo_realpath of symbolic link. */
symlink_program_name = tomoyo_realpath_nofollow(original_name);
if (!symlink_program_name)
goto out;
r.name = real_program_name;
tomoyo_fill_path_info(&r);
s.name = symlink_program_name;
tomoyo_fill_path_info(&s);
l.name = tomoyo_get_last_name(old_domain);
tomoyo_fill_path_info(&l);
/* Check 'alias' directive. */
if (tomoyo_pathcmp(&r, &s)) {
struct tomoyo_alias_entry *ptr;
/* Is this program allowed to be called via symbolic links? */
down_read(&tomoyo_alias_list_lock);
list_for_each_entry(ptr, &tomoyo_alias_list, list) {
if (ptr->is_deleted ||
tomoyo_pathcmp(&r, ptr->original_name) ||
tomoyo_pathcmp(&s, ptr->aliased_name))
continue;
memset(real_program_name, 0, TOMOYO_MAX_PATHNAME_LEN);
strncpy(real_program_name, ptr->aliased_name->name,
TOMOYO_MAX_PATHNAME_LEN - 1);
tomoyo_fill_path_info(&r);
break;
}
up_read(&tomoyo_alias_list_lock);
}
/* Check execute permission. */
retval = tomoyo_check_exec_perm(old_domain, &r);
if (retval < 0)
goto out;
new_domain_name = tmp->buffer;
if (tomoyo_is_domain_initializer(old_domain->domainname, &r, &l)) {
/* Transit to the child of tomoyo_kernel_domain domain. */
snprintf(new_domain_name, TOMOYO_MAX_PATHNAME_LEN + 1,
TOMOYO_ROOT_NAME " " "%s", real_program_name);
} else 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 if (tomoyo_is_domain_keeper(old_domain->domainname, &r, &l)) {
/* Keep current domain. */
domain = old_domain;
} else {
/* Normal domain transition. */
snprintf(new_domain_name, TOMOYO_MAX_PATHNAME_LEN + 1,
"%s %s", old_domain_name, real_program_name);
}
if (domain || strlen(new_domain_name) >= TOMOYO_MAX_PATHNAME_LEN)
goto done;
down_read(&tomoyo_domain_list_lock);
domain = tomoyo_find_domain(new_domain_name);
up_read(&tomoyo_domain_list_lock);
if (domain)
goto done;
if (is_enforce)
goto done;
domain = tomoyo_find_or_assign_new_domain(new_domain_name,
old_domain->profile);
done:
if (domain)
goto out;
printk(KERN_WARNING "TOMOYO-ERROR: Domain '%s' not defined.\n",
new_domain_name);
if (is_enforce)
retval = -EPERM;
else
tomoyo_set_domain_flag(old_domain, false,
TOMOYO_DOMAIN_FLAGS_TRANSITION_FAILED);
out:
if (!domain)
domain = old_domain;
bprm->cred->security = domain;
tomoyo_free(real_program_name);
tomoyo_free(symlink_program_name);
tomoyo_free(tmp);
return retval;
}