/*
* security/tomoyo/common.c
*
* Common functions for TOMOYO.
*
* Copyright (C) 2005-2009 NTT DATA CORPORATION
*
* Version: 2.2.0 2009/04/01
*
*/
#include <linux/uaccess.h>
#include <linux/security.h>
#include <linux/hardirq.h>
#include "common.h"
#include "realpath.h"
#include "tomoyo.h"
/* Lock for protecting policy. */
DEFINE_MUTEX(tomoyo_policy_lock);
/* Has loading policy done? */
bool tomoyo_policy_loaded;
/* String table for functionality that takes 4 modes. */
static const char *tomoyo_mode_4[4] = {
"disabled", "learning", "permissive", "enforcing"
};
/* String table for functionality that takes 2 modes. */
static const char *tomoyo_mode_2[4] = {
"disabled", "enabled", "enabled", "enabled"
};
/*
* tomoyo_control_array is a static data which contains
*
* (1) functionality name used by /sys/kernel/security/tomoyo/profile .
* (2) initial values for "struct tomoyo_profile".
* (3) max values for "struct tomoyo_profile".
*/
static struct {
const char *keyword;
unsigned int current_value;
const unsigned int max_value;
} tomoyo_control_array[TOMOYO_MAX_CONTROL_INDEX] = {
[TOMOYO_MAC_FOR_FILE] = { "MAC_FOR_FILE", 0, 3 },
[TOMOYO_MAX_ACCEPT_ENTRY] = { "MAX_ACCEPT_ENTRY", 2048, INT_MAX },
[TOMOYO_VERBOSE] = { "TOMOYO_VERBOSE", 1, 1 },
};
/*
* tomoyo_profile is a structure which is used for holding the mode of access
* controls. TOMOYO has 4 modes: disabled, learning, permissive, enforcing.
* An administrator can define up to 256 profiles.
* The ->profile of "struct tomoyo_domain_info" is used for remembering
* the profile's number (0 - 255) assigned to that domain.
*/
static struct tomoyo_profile {
unsigned int value[TOMOYO_MAX_CONTROL_INDEX];
const struct tomoyo_path_info *comment;
} *tomoyo_profile_ptr[TOMOYO_MAX_PROFILES];
/* Permit policy management by non-root user? */
static bool tomoyo_manage_by_non_root;
/* Utility functions. */
/* Open operation for /sys/kernel/security/tomoyo/ interface. */
static int tomoyo_open_control(const u8 type, struct file *file);
/* Close /sys/kernel/security/tomoyo/ interface. */
static int tomoyo_close_control(struct file *file);
/* Read operation for /sys/kernel/security/tomoyo/ interface. */
static int tomoyo_read_control(struct file *file, char __user *buffer,
const int buffer_len);
/* Write operation for /sys/kernel/security/tomoyo/ interface. */
static int tomoyo_write_control(struct file *file, const char __user *buffer,
const int buffer_len);
/**
* tomoyo_is_byte_range - Check whether the string isa \ooo style octal value.
*
* @str: Pointer to the string.
*
* Returns true if @str is a \ooo style octal value, false otherwise.
*
* TOMOYO uses \ooo style representation for 0x01 - 0x20 and 0x7F - 0xFF.
* This function verifies that \ooo is in valid range.
*/
static inline bool tomoyo_is_byte_range(const char *str)
{
return *str >= '0' && *str++ <= '3' &&
*str >= '0' && *str++ <= '7' &&
*str >= '0' && *str <= '7';
}
/**
* tomoyo_is_alphabet_char - Check whether the character is an alphabet.
*
* @c: The character to check.
*
* Returns true if @c is an alphabet character, false otherwise.
*/
static inline bool tomoyo_is_alphabet_char(const char c)
{
return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z');
}
/**
* tomoyo_make_byte - Make byte value from three octal characters.
*
* @c1: The first character.
* @c2: The second character.
* @c3: The third character.
*
* Returns byte value.
*/
static inline u8 tomoyo_make_byte(const u8 c1, const u8 c2, const u8 c3)
{
return ((c1 - '0') << 6) + ((c2 - '0') << 3) + (c3 - '0');
}
/**
* tomoyo_str_starts - Check whether the given string starts with the given keyword.
*
* @src: Pointer to pointer to the string.
* @find: Pointer to the keyword.
*
* Returns true if @src starts with @find, false otherwise.
*
* The @src is updated to point the first character after the @find
* if @src starts with @find.
*/
static bool tomoyo_str_starts(char **src, const char *find)
{
const int len = strlen(find);
char *tmp = *src;
if (strncmp(tmp, find, len))
return false;
tmp += len;
*src = tmp;
return true;
}
/**
* tomoyo_normalize_line - Format string.
*
* @buffer: The line to normalize.
*
* Leading and trailing whitespaces are removed.
* Multiple whitespaces are packed into single space.
*
* Returns nothing.
*/
static void tomoyo_normalize_line(unsigned char *buffer)
{
unsigned char *sp = buffer;
unsigned char *dp = buffer;
bool first = true;
while (tomoyo_is_invalid(*sp))
sp++;
while (*sp) {
if (!first)
*dp++ = ' ';
first = false;
while (tomoyo_is_valid(*sp))
*dp++ = *sp++;
while (tomoyo_is_invalid(*sp))
sp++;
}
*dp = '\0';
}
/**
* tomoyo_is_correct_path - Validate a pathname.
* @filename: The pathname to check.
* @start_type: Should the pathname start with '/'?
* 1 = must / -1 = must not / 0 = don't care
* @pattern_type: Can the pathname contain a wildcard?
* 1 = must / -1 = must not / 0 = don't care
* @end_type: Should the pathname end with '/'?
* 1 = must / -1 = must not / 0 = don't care
* @function: The name of function calling me.
*
* Check whether the given filename follows the naming rules.
* Returns true if @filename follows the naming rules, false otherwise.
*/
bool tomoyo_is_correct_path(const char *filename, const s8 start_type,
const s8 pattern_type, const s8 end_type,
const char *function)
{
const char *const start = filename;
bool in_repetition = false;
bool contains_pattern = false;
unsigned char c;
unsigned char d;
unsigned char e;
const char *original_filename = filename;
if (!filename)
goto out;
c = *filename;
if (start_type == 1) { /* Must start with '/' */
if (c != '/')
goto out;
} else if (start_type == -1) { /* Must not start with '/' */
if (c == '/')
goto out;
}
if (c)
c = *(filename + strlen(filename) - 1);
if (end_type == 1) { /* Must end with '/' */
if (c != '/')
goto out;
} else if (end_type == -1) { /* Must not end with '/' */
if (c == '/')
goto out;
}
while (1) {
c = *filename++;
if (!c)
break;
if (c == '\\') {
c = *filename++;
switch (c) {
case '\\': /* "\\" */
continue;
case '$': /* "\$" */
case '+': /* "\+" */
case '?': /* "\?" */
case '*': /* "\*" */
case '@': /* "\@" */
case 'x': /* "\x" */
case 'X': /* "\X" */
case 'a': /* "\a" */
case 'A': /* "\A" */
case '-': /* "\-" */
if (pattern_type == -1)
break; /* Must not contain pattern */
contains_pattern = true;
continue;
case '{': /* "/\{" */
if (filename - 3 < start ||
*(filename - 3) != '/')
break;
if (pattern_type == -1)
break; /* Must not contain pattern */
contains_pattern = true;
in_repetition = true;
continue;
case '}': /* "\}/" */
if (*filename != '/')
break;
if (!in_repetition)
break;
in_repetition = false;
continue;
case '0': /* "\ooo" */
case '1':
case '2':
case '3':
d = *filename++;
if (d < '0' || d > '7')
break;
e = *filename++;
if (e < '0' || e > '7')
break;
c = tomoyo_make_byte(c, d, e);
if (tomoyo_is_invalid(c))
continue; /* pattern is not \000 */
}
goto out;
} else if (in_repetition && c == '/') {
goto out;
} else if (tomoyo_is_invalid(c)) {
goto out;
}
}
if (pattern_type == 1) { /* Must contain pattern */
if (!contains_pattern)
goto out;
}
if (in_repetition)
goto out;
return true;
out:
printk(KERN_DEBUG "%s: Invalid pathname '%s'\n", function,
original_filename);
return false;
}
/**
* tomoyo_is_correct_domain - Check whether the given domainname follows the naming rules.
* @domainname: The domainname to check.
* @function: The name of function calling me.
*
* Returns true if @domainname follows the naming rules, false otherwise.
*/
bool tomoyo_is_correct_domain(const unsigned char *domainname,
const char *function)
{
unsigned char c;
unsigned char d;
unsigned char e;
const char *org_domainname = domainname;
if (!domainname || strncmp(domainname, TOMOYO_ROOT_NAME,
TOMOYO_ROOT_NAME_LEN))
goto out;
domainname += TOMOYO_ROOT_NAME_LEN;
if (!*domainname)
return true;
do {
if (*domainname++ != ' ')
goto out;
if (*domainname++ != '/')
goto out;
while ((c = *domainname) != '\0' && c != ' ') {
domainname++;
if (c == '\\') {
c = *domainname++;
switch ((c)) {
case '\\': /* "\\" */
continue;
case '0': /* "\ooo" */
case '1':
case '2':
case '3':
d = *domainname++;
if (d < '0' || d > '7')
break;
e = *domainname++;
if (e < '0' || e > '7')
break;
c = tomoyo_make_byte(c, d, e);
if (tomoyo_is_invalid(c))
/* pattern is not \000 */
continue;
}
goto out;
} else if (tomoyo_is_invalid(c)) {
goto out;
}
}
} while (*domainname);
return true;
out:
printk(KERN_DEBUG "%s: Invalid domainname '%s'\n", function,
org_domainname);
return false;
}
/**
* tomoyo_is_domain_def - Check whether the given token can be a domainname.
*
* @buffer: The token to check.
*
* Returns true if @buffer possibly be a domainname, false otherwise.
*/
bool tomoyo_is_domain_def(const unsigned char *buffer)
{
return !strncmp(buffer, TOMOYO_ROOT_NAME, TOMOYO_ROOT_NAME_LEN);
}
/**
* tomoyo_find_domain - Find a domain by the given name.
*
* @domainname: The domainname to find.
*
* Returns pointer to "struct tomoyo_domain_info" if found, NULL otherwise.
*
* Caller holds tomoyo_read_lock().
*/
struct tomoyo_domain_info *tomoyo_find_domain(const char *domainname)
{
struct tomoyo_domain_info *domain;
struct tomoyo_path_info name;
name.name = domainname;
tomoyo_fill_path_info(&name);
list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
if (!domain->is_deleted &&
!tomoyo_pathcmp(&name, domain->domainname))
return domain;
}
return NULL;
}
/**
* tomoyo_const_part_length - Evaluate the initial length without a pattern in a token.
*
* @filename: The string to evaluate.
*
* Returns the initial length without a pattern in @filename.
*/
static int tomoyo_const_part_length(const char *filename)
{
char c;
int len = 0;
if (!filename)
return 0;
while ((c = *filename++) != '\0') {
if (c != '\\') {
len++;
continue;
}
c = *filename++;
switch (c) {
case '\\': /* "\\" */
len += 2;
continue;
case '0': /* "\ooo" */
case '1':
case '2':
case '3':
c = *filename++;
if (c < '0' || c > '7')
break;
c = *filename++;
if (c < '0' || c > '7')
break;
len += 4;
continue;
}
break;
}
return len;
}
/**
* tomoyo_fill_path_info - Fill in "struct tomoyo_path_info" members.
*
* @ptr: Pointer to "struct tomoyo_path_info" to fill in.
*
* The caller sets "struct tomoyo_path_info"->name.
*/
void tomoyo_fill_path_info(struct tomoyo_path_info *ptr)
{
const char *name = ptr->name;
const int len = strlen(name);
ptr->const_len = tomoyo_const_part_length(name);
ptr->is_dir = len && (name[len - 1] == '/');
ptr->is_patterned = (ptr->const_len < len);
ptr->hash = full_name_hash(name, len);
}
/**
* tomoyo_file_matches_pattern2 - Pattern matching without '/' character
* and "\-" pattern.
*
* @filename: The start of string to check.
* @filename_end: The end of string to check.
* @pattern: The start of pattern to compare.
* @pattern_end: The end of pattern to compare.
*
* Returns true if @filename matches @pattern, false otherwise.
*/
static bool tomoyo_file_matches_pattern2(const char *filename,
const char *filename_end,
const char *pattern,
const char *pattern_end)
{
while (filename < filename_end && pattern < pattern_end) {
char c;
if (*pattern != '\\') {
if (*filename++ != *pattern++)
return false;
continue;
}
c = *filename;
pattern++;
switch (*pattern) {
int i;
int j;
case '?':
if (c == '/') {
return false;
} else if (c == '\\') {
if (filename[1] == '\\')
filename++;
else if (tomoyo_is_byte_range(filename + 1))
filename += 3;
else
return false;
}
break;
case '\\':
if (c != '\\')
return false;
if (*++filename != '\\')
return false;
break;
case '+':
if (!isdigit(c))
return false;
break;
case 'x':
if (!isxdigit(c))
return false;
break;
case 'a':
if (!tomoyo_is_alphabet_char(c))
return false;
break;
case '0':
case '1':
case '2':
case '3':
if (c == '\\' && tomoyo_is_byte_range(filename + 1)
&& strncmp(filename + 1, pattern, 3) == 0) {
filename += 3;
pattern += 2;
break;
}
return false; /* Not matched. */
case '*':
case '@':
for (i = 0; i <= filename_end - filename; i++) {
if (tomoyo_file_matches_pattern2(
filename + i, filename_end,
pattern + 1, pattern_end))
return true;
c = filename[i];
if (c == '.' && *pattern == '@')
break;
if (c != '\\')
continue;
if (filename[i + 1] == '\\')
i++;
else if (tomoyo_is_byte_range(filename + i + 1))
i += 3;
else
break; /* Bad pattern. */
}
return false; /* Not matched. */
default:
j = 0;
c = *pattern;
if (c == '$') {
while (isdigit(filename[j]))
j++;
} else if (c == 'X') {
while (isxdigit(filename[j]))
j++;
} else if (c == 'A') {
while (tomoyo_is_alphabet_char(filename[j]))
j++;
}
for (i = 1; i <= j; i++) {
if (tomoyo_file_matches_pattern2(
filename + i, filename_end,
pattern + 1, pattern_end))
return true;
}
return false; /* Not matched or bad pattern. */
}
filename++;
pattern++;
}
while (*pattern == '\\' &&
(*(pattern + 1) == '*' || *(pattern + 1) == '@'))
pattern += 2;
return filename == filename_end && pattern == pattern_end;
}
/**
* tomoyo_file_matches_pattern - Pattern matching without without '/' character.
*
* @filename: The start of string to check.
* @filename_end: The end of string to check.
* @pattern: The start of pattern to compare.
* @pattern_end: The end of pattern to compare.
*
* Returns true if @filename matches @pattern, false otherwise.
*/
static bool tomoyo_file_matches_pattern(const char *filename,
const char *filename_end,
const char *pattern,
const char *pattern_end)
{
const char *pattern_start = pattern;
bool first = true;
bool result;
while (pattern < pattern_end - 1) {
/* Split at "\-" pattern. */
if (*pattern++ != '\\' || *pattern++ != '-')
continue;
result = tomoyo_file_matches_pattern2(filename,
filename_end,
pattern_start,
pattern - 2);
if (first)
result = !result;
if (result)
return false;
first = false;
pattern_start = pattern;
}
result = tomoyo_file_matches_pattern2(filename, filename_end,
pattern_start, pattern_end);
return first ? result : !result;
}
/**
* tomoyo_path_matches_pattern2 - Do pathname pattern matching.
*
* @f: The start of string to check.
* @p: The start of pattern to compare.
*
* Returns true if @f matches @p, false otherwise.
*/
static bool tomoyo_path_matches_pattern2(const char *f, const char *p)
{
const char *f_delimiter;
const char *p_delimiter;
while (*f && *p) {
f_delimiter = strchr(f, '/');
if (!f_delimiter)
f_delimiter = f + strlen(f);
p_delimiter = strchr(p, '/');
if (!p_delimiter)
p_delimiter = p + strlen(p);
if (*p == '\\' && *(p + 1) == '{')
goto recursive;
if (!tomoyo_file_matches_pattern(f, f_delimiter, p,
p_delimiter))
return false;
f = f_delimiter;
if (*f)
f++;
p = p_delimiter;
if (*p)
p++;
}
/* Ignore trailing "\*" and "\@" in @pattern. */
while (*p == '\\' &&
(*(p + 1) == '*' || *(p + 1) == '@'))
p += 2;
return !*f && !*p;
recursive:
/*
* The "\{" pattern is permitted only after '/' character.
* This guarantees that below "*(p - 1)" is safe.
* Also, the "\}" pattern is permitted only before '/' character
* so that "\{" + "\}" pair will not break the "\-" operator.
*/
if (*(p - 1) != '/' || p_delimiter <= p + 3 || *p_delimiter != '/' ||
*(p_delimiter - 1) != '}' || *(p_delimiter - 2) != '\\')
return false; /* Bad pattern. */
do {
/* Compare current component with pattern. */
if (!tomoyo_file_matches_pattern(f, f_delimiter, p + 2,
p_delimiter - 2))
break;
/* Proceed to next component. */
f = f_delimiter;
if (!*f)
break;
f++;
/* Continue comparison. */
if (tomoyo_path_matches_pattern2(f, p_delimiter + 1))
return true;
f_delimiter = strchr(f, '/');
} while (f_delimiter);
return false; /* Not matched. */
}
/**
* tomoyo_path_matches_pattern - Check whether the given filename matches the given pattern.
*
* @filename: The filename to check.
* @pattern: The pattern to compare.
*
* Returns true if matches, false otherwise.
*
* The following patterns are available.
* \\ \ itself.
* \ooo Octal representation of a byte.
* \* Zero or more repetitions of characters other than '/'.
* \@ Zero or more repetitions of characters other than '/' or '.'.
* \? 1 byte character other than '/'.
* \$ One or more repetitions of decimal digits.
* \+ 1 decimal digit.
* \X One or more repetitions of hexadecimal digits.
* \x 1 hexadecimal digit.
* \A One or more repetitions of alphabet characters.
* \a 1 alphabet character.
*
* \- Subtraction operator.
*
* /\{dir\}/ '/' + 'One or more repetitions of dir/' (e.g. /dir/ /dir/dir/
* /dir/dir/dir/ ).
*/
bool tomoyo_path_matches_pattern(const struct tomoyo_path_info *filename,
const struct tomoyo_path_info *pattern)
{
const char *f = filename->name;
const char *p = pattern->name;
const int len = pattern->const_len;
/* If @pattern doesn't contain pattern, I can use strcmp(). */
if (!pattern->is_patterned)
return !tomoyo_pathcmp(filename, pattern);
/* Don't compare directory and non-directory. */
if (filename->is_dir != pattern->is_dir)
return false;
/* Compare the initial length without patterns. */
if (strncmp(f, p, len))
return false;
f += len;
p += len;
return tomoyo_path_matches_pattern2(f, p);
}
/**
* tomoyo_io_printf - Transactional printf() to "struct tomoyo_io_buffer" structure.
*
* @head: Pointer to "struct tomoyo_io_buffer".
* @fmt: The printf()'s format string, followed by parameters.
*
* Returns true if output was written, false otherwise.
*
* The snprintf() will truncate, but tomoyo_io_printf() won't.
*/
bool tomoyo_io_printf(struct tomoyo_io_buffer *head, const char *fmt, ...)
{
va_list args;
int len;
int pos = head->read_avail;
int size = head->readbuf_size - pos;
if (size <= 0)
return false;
va_start(args, fmt);
len = vsnprintf(head->read_buf + pos, size, fmt, args);
va_end(args);
if (pos + len >= head->readbuf_size)
return false;
head->read_avail += len;
return true;
}
/**
* tomoyo_get_exe - Get tomoyo_realpath() of current process.
*
* Returns the tomoyo_realpath() of current process on success, NULL otherwise.
*
* This function uses kzalloc(), so the caller must call kfree()
* if this function didn't return NULL.
*/
static const char *tomoyo_get_exe(void)
{
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
const char *cp = NULL;
if (!mm)
return NULL;
down_read(&mm->mmap_sem);
for (vma = mm->mmap; vma; vma = vma->vm_next) {
if ((vma->vm_flags & VM_EXECUTABLE) && vma->vm_file) {
cp = tomoyo_realpath_from_path(&vma->vm_file->f_path);
break;
}
}
up_read(&mm->mmap_sem);
return cp;
}
/**
* tomoyo_get_msg - Get warning message.
*
* @is_enforce: Is it enforcing mode?
*
* Returns "ERROR" or "WARNING".
*/
const char *tomoyo_get_msg(const bool is_enforce)
{
if (is_enforce)
return "ERROR";
else
return "WARNING";
}
/**
* tomoyo_check_flags - Check mode for specified functionality.
*
* @domain: Pointer to "struct tomoyo_domain_info".
* @index: The functionality to check mode.
*
* TOMOYO checks only process context.
* This code disables TOMOYO's enforcement in case the function is called from
* interrupt context.
*/
unsigned int tomoyo_check_flags(const struct tomoyo_domain_info *domain,
const u8 index)
{
const u8 profile = domain->profile;
if (WARN_ON(in_interrupt()))
return 0;
return tomoyo_policy_loaded && index < TOMOYO_MAX_CONTROL_INDEX
#if TOMOYO_MAX_PROFILES != 256
&& profile < TOMOYO_MAX_PROFILES
#endif
&& tomoyo_profile_ptr[profile] ?
tomoyo_profile_ptr[profile]->value[index] : 0;
}
/**
* tomoyo_verbose_mode - Check whether TOMOYO is verbose mode.
*
* @domain: Pointer to "struct tomoyo_domain_info".
*
* Returns true if domain policy violation warning should be printed to
* console.
*/
bool tomoyo_verbose_mode(const struct tomoyo_domain_info *domain)
{
return tomoyo_check_flags(domain, TOMOYO_VERBOSE) != 0;
}
/**
* tomoyo_domain_quota_is_ok - Check for domain's quota.
*
* @domain: Pointer to "struct tomoyo_domain_info".
*
* Returns true if the domain is not exceeded quota, false otherwise.
*
* Caller holds tomoyo_read_lock().
*/
bool tomoyo_domain_quota_is_ok(struct tomoyo_domain_info * const domain)
{
unsigned int count = 0;
struct tomoyo_acl_info *ptr;
if (!domain)
return true;
list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
switch (ptr->type) {
struct tomoyo_single_path_acl_record *acl;
u32 perm;
u8 i;
case TOMOYO_TYPE_SINGLE_PATH_ACL:
acl = container_of(ptr,
struct tomoyo_single_path_acl_record,
head);
perm = acl->perm | (((u32) acl->perm_high) << 16);
for (i = 0; i < TOMOYO_MAX_SINGLE_PATH_OPERATION; i++)
if (perm & (1 << i))
count++;
if (perm & (1 << TOMOYO_TYPE_READ_WRITE_ACL))
count -= 2;
break;
case TOMOYO_TYPE_DOUBLE_PATH_ACL:
perm = container_of(ptr,
struct tomoyo_double_path_acl_record,
head)->perm;
for (i = 0; i < TOMOYO_MAX_DOUBLE_PATH_OPERATION; i++)
if (perm & (1 << i))
count++;
break;
}
}
if (count < tomoyo_check_flags(domain, TOMOYO_MAX_ACCEPT_ENTRY))
return true;
if (!domain->quota_warned) {
domain->quota_warned = true;
printk(KERN_WARNING "TOMOYO-WARNING: "
"Domain '%s' has so many ACLs to hold. "
"Stopped learning mode.\n", domain->domainname->name);
}
return false;
}
/**
* tomoyo_find_or_assign_new_profile - Create a new profile.
*
* @profile: Profile number to create.
*
* Returns pointer to "struct tomoyo_profile" on success, NULL otherwise.
*/
static struct tomoyo_profile *tomoyo_find_or_assign_new_profile(const unsigned
int profile)
{
static DEFINE_MUTEX(lock);
struct tomoyo_profile *ptr = NULL;
int i;
if (profile >= TOMOYO_MAX_PROFILES)
return NULL;
mutex_lock(&lock);
ptr = tomoyo_profile_ptr[profile];
if (ptr)
goto ok;
ptr = kmalloc(sizeof(*ptr), GFP_KERNEL);
if (!tomoyo_memory_ok(ptr)) {
kfree(ptr);
goto ok;
}
for (i = 0; i < TOMOYO_MAX_CONTROL_INDEX; i++)
ptr->value[i] = tomoyo_control_array[i].current_value;
mb(); /* Avoid out-of-order execution. */
tomoyo_profile_ptr[profile] = ptr;
ok:
mutex_unlock(&lock);
return ptr;
}
/**
* tomoyo_write_profile - Write to profile table.
*
* @head: Pointer to "struct tomoyo_io_buffer".
*
* Returns 0 on success, negative value otherwise.
*/
static int tomoyo_write_profile(struct tomoyo_io_buffer *head)
{
char *data = head->write_buf;
unsigned int i;
unsigned int value;
char *cp;
struct tomoyo_profile *profile;
unsigned long num;
cp = strchr(data, '-');
if (cp)
*cp = '\0';
if (strict_strtoul(data, 10, &num))
return -EINVAL;
if (cp)
data = cp + 1;
profile = tomoyo_find_or_assign_new_profile(num);
if (!profile)
return -EINVAL;
cp = strchr(data, '=');
if (!cp)
return -EINVAL;
*cp = '\0';
if (!strcmp(data, "COMMENT")) {
const struct tomoyo_path_info *old_comment = profile->comment;
profile->comment = tomoyo_get_name(cp + 1);
tomoyo_put_name(old_comment);
return 0;
}
for (i = 0; i < TOMOYO_MAX_CONTROL_INDEX; i++) {
if (strcmp(data, tomoyo_control_array[i].keyword))
continue;
if (sscanf(cp + 1, "%u", &value) != 1) {
int j;
const char **modes;
switch (i) {
case TOMOYO_VERBOSE:
modes = tomoyo_mode_2;
break;
default:
modes = tomoyo_mode_4;
break;
}
for (j = 0; j < 4; j++) {
if (strcmp(cp + 1, modes[j]))
continue;
value = j;
break;
}
if (j == 4)
return -EINVAL;
} else if (value > tomoyo_control_array[i].max_value) {
value = tomoyo_control_array[i].max_value;
}
profile->value[i] = value;
return 0;
}
return -EINVAL;
}
/**
* tomoyo_read_profile - Read from profile table.
*
* @head: Pointer to "struct tomoyo_io_buffer".
*
* Returns 0.
*/
static int tomoyo_read_profile(struct tomoyo_io_buffer *head)
{
static const int total = TOMOYO_MAX_CONTROL_INDEX + 1;
int step;
if (head->read_eof)
return 0;
for (step = head->read_step; step < TOMOYO_MAX_PROFILES * total;
step++) {
const u8 index = step / total;
u8 type = step % total;
const struct tomoyo_profile *profile
= tomoyo_profile_ptr[index];
head->read_step = step;
if (!profile)
continue;
if (!type) { /* Print profile' comment tag. */
if (!tomoyo_io_printf(head, "%u-COMMENT=%s\n",
index, profile->comment ?
profile->comment->name : ""))
break;
continue;
}
type--;
if (type < TOMOYO_MAX_CONTROL_INDEX) {
const unsigned int value = profile->value[type];
const char **modes = NULL;
const char *keyword
= tomoyo_control_array[type].keyword;
switch (tomoyo_control_array[type].max_value) {
case 3:
modes = tomoyo_mode_4;
break;
case 1:
modes = tomoyo_mode_2;
break;
}
if (modes) {
if (!tomoyo_io_printf(head, "%u-%s=%s\n", index,
keyword, modes[value]))
break;
} else {
if (!tomoyo_io_printf(head, "%u-%s=%u\n", index,
keyword, value))
break;
}
}
}
if (step == TOMOYO_MAX_PROFILES * total)
head->read_eof = true;
return 0;
}
/*
* tomoyo_policy_manager_entry is a structure which is used for holding list of
* domainnames or programs which are permitted to modify configuration via
* /sys/kernel/security/tomoyo/ interface.
* It has following fields.
*
* (1) "list" which is linked to tomoyo_policy_manager_list .
* (2) "manager" is a domainname or a program's pathname.
* (3) "is_domain" is a bool which is true if "manager" is a domainname, false
* otherwise.
* (4) "is_deleted" is a bool which is true if marked as deleted, false
* otherwise.
*/
struct tomoyo_policy_manager_entry {
struct list_head list;
/* A path to program or a domainname. */
const struct tomoyo_path_info *manager;
bool is_domain; /* True if manager is a domainname. */
bool is_deleted; /* True if this entry is deleted. */
};
/*
* tomoyo_policy_manager_list is used for holding list of domainnames or
* programs which are permitted to modify configuration via
* /sys/kernel/security/tomoyo/ interface.
*
* An entry is added by
*
* # echo '<kernel> /sbin/mingetty /bin/login /bin/bash' > \
* /sys/kernel/security/tomoyo/manager
* (if you want to specify by a domainname)
*
* or
*
* # echo '/usr/lib/ccs/editpolicy' > /sys/kernel/security/tomoyo/manager
* (if you want to specify by a program's location)
*
* and is deleted by
*
* # echo 'delete <kernel> /sbin/mingetty /bin/login /bin/bash' > \
* /sys/kernel/security/tomoyo/manager
*
* or
*
* # echo 'delete /usr/lib/ccs/editpolicy' > \
* /sys/kernel/security/tomoyo/manager
*
* and all entries are retrieved by
*
* # cat /sys/kernel/security/tomoyo/manager
*/
static LIST_HEAD(tomoyo_policy_manager_list);
/**
* tomoyo_update_manager_entry - Add a manager entry.
*
* @manager: The path to manager or the domainnamme.
* @is_delete: True if it is a delete request.
*
* Returns 0 on success, negative value otherwise.
*
* Caller holds tomoyo_read_lock().
*/
static int tomoyo_update_manager_entry(const char *manager,
const bool is_delete)
{
struct tomoyo_policy_manager_entry *entry = NULL;
struct tomoyo_policy_manager_entry *ptr;
const struct tomoyo_path_info *saved_manager;
int error = is_delete ? -ENOENT : -ENOMEM;
bool is_domain = false;
if (tomoyo_is_domain_def(manager)) {
if (!tomoyo_is_correct_domain(manager, __func__))
return -EINVAL;
is_domain = true;
} else {
if (!tomoyo_is_correct_path(manager, 1, -1, -1, __func__))
return -EINVAL;
}
saved_manager = tomoyo_get_name(manager);
if (!saved_manager)
return -ENOMEM;
if (!is_delete)
entry = kmalloc(sizeof(*entry), GFP_KERNEL);
mutex_lock(&tomoyo_policy_lock);
list_for_each_entry_rcu(ptr, &tomoyo_policy_manager_list, list) {
if (ptr->manager != saved_manager)
continue;
ptr->is_deleted = is_delete;
error = 0;
break;
}
if (!is_delete && error && tomoyo_memory_ok(entry)) {
entry->manager = saved_manager;
saved_manager = NULL;
entry->is_domain = is_domain;
list_add_tail_rcu(&entry->list, &tomoyo_policy_manager_list);
entry = NULL;
error = 0;
}
mutex_unlock(&tomoyo_policy_lock);
tomoyo_put_name(saved_manager);
kfree(entry);
return error;
}
/**
* tomoyo_write_manager_policy - Write manager policy.
*
* @head: Pointer to "struct tomoyo_io_buffer".
*
* Returns 0 on success, negative value otherwise.
*
* Caller holds tomoyo_read_lock().
*/
static int tomoyo_write_manager_policy(struct tomoyo_io_buffer *head)
{
char *data = head->write_buf;
bool is_delete = tomoyo_str_starts(&data, TOMOYO_KEYWORD_DELETE);
if (!strcmp(data, "manage_by_non_root")) {
tomoyo_manage_by_non_root = !is_delete;
return 0;
}
return tomoyo_update_manager_entry(data, is_delete);
}
/**
* tomoyo_read_manager_policy - Read manager policy.
*
* @head: Pointer to "struct tomoyo_io_buffer".
*
* Returns 0.
*
* Caller holds tomoyo_read_lock().
*/
static int tomoyo_read_manager_policy(struct tomoyo_io_buffer *head)
{
struct list_head *pos;
bool done = true;
if (head->read_eof)
return 0;
list_for_each_cookie(pos, head->read_var2,
&tomoyo_policy_manager_list) {
struct tomoyo_policy_manager_entry *ptr;
ptr = list_entry(pos, struct tomoyo_policy_manager_entry,
list);
if (ptr->is_deleted)
continue;
done = tomoyo_io_printf(head, "%s\n", ptr->manager->name);
if (!done)
break;
}
head->read_eof = done;
return 0;
}
/**
* tomoyo_is_policy_manager - Check whether the current process is a policy manager.
*
* Returns true if the current process is permitted to modify policy
* via /sys/kernel/security/tomoyo/ interface.
*
* Caller holds tomoyo_read_lock().
*/
static bool tomoyo_is_policy_manager(void)
{
struct tomoyo_policy_manager_entry *ptr;
const char *exe;
const struct task_struct *task = current;
const struct tomoyo_path_info *domainname = tomoyo_domain()->domainname;
bool found = false;
if (!tomoyo_policy_loaded)
return true;
if (!tomoyo_manage_by_non_root && (task->cred->uid || task->cred->euid))
return false;
list_for_each_entry_rcu(ptr, &tomoyo_policy_manager_list, list) {
if (!ptr->is_deleted && ptr->is_domain
&& !tomoyo_pathcmp(domainname, ptr->manager)) {
found = true;
break;
}
}
if (found)
return true;
exe = tomoyo_get_exe();
if (!exe)
return false;
list_for_each_entry_rcu(ptr, &tomoyo_policy_manager_list, list) {
if (!ptr->is_deleted && !ptr->is_domain
&& !strcmp(exe, ptr->manager->name)) {
found = true;
break;
}
}
if (!found) { /* Reduce error messages. */
static pid_t last_pid;
const pid_t pid = current->pid;
if (last_pid != pid) {
printk(KERN_WARNING "%s ( %s ) is not permitted to "
"update policies.\n", domainname->name, exe);
last_pid = pid;
}
}
kfree(exe);
return found;
}
/**
* tomoyo_is_select_one - Parse select command.
*
* @head: Pointer to "struct tomoyo_io_buffer".
* @data: String to parse.
*
* Returns true on success, false otherwise.
*
* Caller holds tomoyo_read_lock().
*/
static bool tomoyo_is_select_one(struct tomoyo_io_buffer *head,
const char *data)
{
unsigned int pid;
struct tomoyo_domain_info *domain = NULL;
if (sscanf(data, "pid=%u", &pid) == 1) {
struct task_struct *p;
read_lock(&tasklist_lock);
p = find_task_by_vpid(pid);
if (p)
domain = tomoyo_real_domain(p);
read_unlock(&tasklist_lock);
} else if (!strncmp(data, "domain=", 7)) {
if (tomoyo_is_domain_def(data + 7))
domain = tomoyo_find_domain(data + 7);
} else
return false;
head->write_var1 = domain;
/* Accessing read_buf is safe because head->io_sem is held. */
if (!head->read_buf)
return true; /* Do nothing if open(O_WRONLY). */
head->read_avail = 0;
tomoyo_io_printf(head, "# select %s\n", data);
head->read_single_domain = true;
head->read_eof = !domain;
if (domain) {
struct tomoyo_domain_info *d;
head->read_var1 = NULL;
list_for_each_entry_rcu(d, &tomoyo_domain_list, list) {
if (d == domain)
break;
head->read_var1 = &d->list;
}
head->read_var2 = NULL;
head->read_bit = 0;
head->read_step = 0;
if (domain->is_deleted)
tomoyo_io_printf(head, "# This is a deleted domain.\n");
}
return true;
}
/**
* tomoyo_delete_domain - Delete a domain.
*
* @domainname: The name of domain.
*
* Returns 0.
*
* Caller holds tomoyo_read_lock().
*/
static int tomoyo_delete_domain(char *domainname)
{
struct tomoyo_domain_info *domain;
struct tomoyo_path_info name;
name.name = domainname;
tomoyo_fill_path_info(&name);
mutex_lock(&tomoyo_policy_lock);
/* Is there an active domain? */
list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
/* Never delete tomoyo_kernel_domain */
if (domain == &tomoyo_kernel_domain)
continue;
if (domain->is_deleted ||
tomoyo_pathcmp(domain->domainname, &name))
continue;
domain->is_deleted = true;
break;
}
mutex_unlock(&tomoyo_policy_lock);
return 0;
}
/**
* tomoyo_write_domain_policy - Write domain policy.
*
* @head: Pointer to "struct tomoyo_io_buffer".
*
* Returns 0 on success, negative value otherwise.
*
* Caller holds tomoyo_read_lock().
*/
static int tomoyo_write_domain_policy(struct tomoyo_io_buffer *head)
{
char *data = head->write_buf;
struct tomoyo_domain_info *domain = head->write_var1;
bool is_delete = false;
bool is_select = false;
unsigned int profile;
if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_DELETE))
is_delete = true;
else if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_SELECT))
is_select = true;
if (is_select && tomoyo_is_select_one(head, data))
return 0;
/* Don't allow updating policies by non manager programs. */
if (!tomoyo_is_policy_manager())
return -EPERM;
if (tomoyo_is_domain_def(data)) {
domain = NULL;
if (is_delete)
tomoyo_delete_domain(data);
else if (is_select)
domain = tomoyo_find_domain(data);
else
domain = tomoyo_find_or_assign_new_domain(data, 0);
head->write_var1 = domain;
return 0;
}
if (!domain)
return -EINVAL;
if (sscanf(data, TOMOYO_KEYWORD_USE_PROFILE "%u", &profile) == 1
&& profile < TOMOYO_MAX_PROFILES) {
if (tomoyo_profile_ptr[profile] || !tomoyo_policy_loaded)
domain->profile = (u8) profile;
return 0;
}
if (!strcmp(data, TOMOYO_KEYWORD_IGNORE_GLOBAL_ALLOW_READ)) {
domain->ignore_global_allow_read = !is_delete;
return 0;
}
return tomoyo_write_file_policy(data, domain, is_delete);
}
/**
* tomoyo_print_single_path_acl - Print a single path ACL entry.
*
* @head: Pointer to "struct tomoyo_io_buffer".
* @ptr: Pointer to "struct tomoyo_single_path_acl_record".
*
* Returns true on success, false otherwise.
*/
static bool tomoyo_print_single_path_acl(struct tomoyo_io_buffer *head,
struct tomoyo_single_path_acl_record *
ptr)
{
int pos;
u8 bit;
const char *atmark = "";
const char *filename;
const u32 perm = ptr->perm | (((u32) ptr->perm_high) << 16);
filename = ptr->filename->name;
for (bit = head->read_bit; bit < TOMOYO_MAX_SINGLE_PATH_OPERATION;
bit++) {
const char *msg;
if (!(perm & (1 << bit)))
continue;
/* Print "read/write" instead of "read" and "write". */
if ((bit == TOMOYO_TYPE_READ_ACL ||
bit == TOMOYO_TYPE_WRITE_ACL)
&& (perm & (1 << TOMOYO_TYPE_READ_WRITE_ACL)))
continue;
msg = tomoyo_sp2keyword(bit);
pos = head->read_avail;
if (!tomoyo_io_printf(head, "allow_%s %s%s\n", msg,
atmark, filename))
goto out;
}
head->read_bit = 0;
return true;
out:
head->read_bit = bit;
head->read_avail = pos;
return false;
}
/**
* tomoyo_print_double_path_acl - Print a double path ACL entry.
*
* @head: Pointer to "struct tomoyo_io_buffer".
* @ptr: Pointer to "struct tomoyo_double_path_acl_record".
*
* Returns true on success, false otherwise.
*/
static bool tomoyo_print_double_path_acl(struct tomoyo_io_buffer *head,
struct tomoyo_double_path_acl_record *
ptr)
{
int pos;
const char *atmark1 = "";
const char *atmark2 = "";
const char *filename1;
const char *filename2;
const u8 perm = ptr->perm;
u8 bit;
filename1 = ptr->filename1->name;
filename2 = ptr->filename2->name;
for (bit = head->read_bit; bit < TOMOYO_MAX_DOUBLE_PATH_OPERATION;
bit++) {
const char *msg;
if (!(perm & (1 << bit)))
continue;
msg = tomoyo_dp2keyword(bit);
pos = head->read_avail;
if (!tomoyo_io_printf(head, "allow_%s %s%s %s%s\n", msg,
atmark1, filename1, atmark2, filename2))
goto out;
}
head->read_bit = 0;
return true;
out:
head->read_bit = bit;
head->read_avail = pos;
return false;
}
/**
* tomoyo_print_entry - Print an ACL entry.
*
* @head: Pointer to "struct tomoyo_io_buffer".
* @ptr: Pointer to an ACL entry.
*
* Returns true on success, false otherwise.
*/
static bool tomoyo_print_entry(struct tomoyo_io_buffer *head,
struct tomoyo_acl_info *ptr)
{
const u8 acl_type = ptr->type;
if (acl_type == TOMOYO_TYPE_SINGLE_PATH_ACL) {
struct tomoyo_single_path_acl_record *acl
= container_of(ptr,
struct tomoyo_single_path_acl_record,
head);
return tomoyo_print_single_path_acl(head, acl);
}
if (acl_type == TOMOYO_TYPE_DOUBLE_PATH_ACL) {
struct tomoyo_double_path_acl_record *acl
= container_of(ptr,
struct tomoyo_double_path_acl_record,
head);
return tomoyo_print_double_path_acl(head, acl);
}
BUG(); /* This must not happen. */
return false;
}
/**
* tomoyo_read_domain_policy - Read domain policy.
*
* @head: Pointer to "struct tomoyo_io_buffer".
*
* Returns 0.
*
* Caller holds tomoyo_read_lock().
*/
static int tomoyo_read_domain_policy(struct tomoyo_io_buffer *head)
{
struct list_head *dpos;
struct list_head *apos;
bool done = true;
if (head->read_eof)
return 0;
if (head->read_step == 0)
head->read_step = 1;
list_for_each_cookie(dpos, head->read_var1, &tomoyo_domain_list) {
struct tomoyo_domain_info *domain;
const char *quota_exceeded = "";
const char *transition_failed = "";
const char *ignore_global_allow_read = "";
domain = list_entry(dpos, struct tomoyo_domain_info, list);
if (head->read_step != 1)
goto acl_loop;
if (domain->is_deleted && !head->read_single_domain)
continue;
/* Print domainname and flags. */
if (domain->quota_warned)
quota_exceeded = "quota_exceeded\n";
if (domain->transition_failed)
transition_failed = "transition_failed\n";
if (domain->ignore_global_allow_read)
ignore_global_allow_read
= TOMOYO_KEYWORD_IGNORE_GLOBAL_ALLOW_READ "\n";
done = tomoyo_io_printf(head, "%s\n" TOMOYO_KEYWORD_USE_PROFILE
"%u\n%s%s%s\n",
domain->domainname->name,
domain->profile, quota_exceeded,
transition_failed,
ignore_global_allow_read);
if (!done)
break;
head->read_step = 2;
acl_loop:
if (head->read_step == 3)
goto tail_mark;
/* Print ACL entries in the domain. */
list_for_each_cookie(apos, head->read_var2,
&domain->acl_info_list) {
struct tomoyo_acl_info *ptr
= list_entry(apos, struct tomoyo_acl_info,
list);
done = tomoyo_print_entry(head, ptr);
if (!done)
break;
}
if (!done)
break;
head->read_step = 3;
tail_mark:
done = tomoyo_io_printf(head, "\n");
if (!done)
break;
head->read_step = 1;
if (head->read_single_domain)
break;
}
head->read_eof = done;
return 0;
}
/**
* tomoyo_write_domain_profile - Assign profile for specified domain.
*
* @head: Pointer to "struct tomoyo_io_buffer".
*
* Returns 0 on success, -EINVAL otherwise.
*
* This is equivalent to doing
*
* ( echo "select " $domainname; echo "use_profile " $profile ) |
* /usr/lib/ccs/loadpolicy -d
*
* Caller holds tomoyo_read_lock().
*/
static int tomoyo_write_domain_profile(struct tomoyo_io_buffer *head)
{
char *data = head->write_buf;
char *cp = strchr(data, ' ');
struct tomoyo_domain_info *domain;
unsigned long profile;
if (!cp)
return -EINVAL;
*cp = '\0';
domain = tomoyo_find_domain(cp + 1);
if (strict_strtoul(data, 10, &profile))
return -EINVAL;
if (domain && profile < TOMOYO_MAX_PROFILES
&& (tomoyo_profile_ptr[profile] || !tomoyo_policy_loaded))
domain->profile = (u8) profile;
return 0;
}
/**
* tomoyo_read_domain_profile - Read only domainname and profile.
*
* @head: Pointer to "struct tomoyo_io_buffer".
*
* Returns list of profile number and domainname pairs.
*
* This is equivalent to doing
*
* grep -A 1 '^<kernel>' /sys/kernel/security/tomoyo/domain_policy |
* awk ' { if ( domainname == "" ) { if ( $1 == "<kernel>" )
* domainname = $0; } else if ( $1 == "use_profile" ) {
* print $2 " " domainname; domainname = ""; } } ; '
*
* Caller holds tomoyo_read_lock().
*/
static int tomoyo_read_domain_profile(struct tomoyo_io_buffer *head)
{
struct list_head *pos;
bool done = true;
if (head->read_eof)
return 0;
list_for_each_cookie(pos, head->read_var1, &tomoyo_domain_list) {
struct tomoyo_domain_info *domain;
domain = list_entry(pos, struct tomoyo_domain_info, list);
if (domain->is_deleted)
continue;
done = tomoyo_io_printf(head, "%u %s\n", domain->profile,
domain->domainname->name);
if (!done)
break;
}
head->read_eof = done;
return 0;
}
/**
* tomoyo_write_pid: Specify PID to obtain domainname.
*
* @head: Pointer to "struct tomoyo_io_buffer".
*
* Returns 0.
*/
static int tomoyo_write_pid(struct tomoyo_io_buffer *head)
{
unsigned long pid;
/* No error check. */
strict_strtoul(head->write_buf, 10, &pid);
head->read_step = (int) pid;
head->read_eof = false;
return 0;
}
/**
* tomoyo_read_pid - Get domainname of the specified PID.
*
* @head: Pointer to "struct tomoyo_io_buffer".
*
* Returns the domainname which the specified PID is in on success,
* empty string otherwise.
* The PID is specified by tomoyo_write_pid() so that the user can obtain
* using read()/write() interface rather than sysctl() interface.
*/
static int tomoyo_read_pid(struct tomoyo_io_buffer *head)
{
if (head->read_avail == 0 && !head->read_eof) {
const int pid = head->read_step;
struct task_struct *p;
struct tomoyo_domain_info *domain = NULL;
read_lock(&tasklist_lock);
p = find_task_by_vpid(pid);
if (p)
domain = tomoyo_real_domain(p);
read_unlock(&tasklist_lock);
if (domain)
tomoyo_io_printf(head, "%d %u %s", pid, domain->profile,
domain->domainname->name);
head->read_eof = true;
}
return 0;
}
/**
* tomoyo_write_exception_policy - Write exception policy.
*
* @head: Pointer to "struct tomoyo_io_buffer".
*
* Returns 0 on success, negative value otherwise.
*
* Caller holds tomoyo_read_lock().
*/
static int tomoyo_write_exception_policy(struct tomoyo_io_buffer *head)
{
char *data = head->write_buf;
bool is_delete = tomoyo_str_starts(&data, TOMOYO_KEYWORD_DELETE);
if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_KEEP_DOMAIN))
return tomoyo_write_domain_keeper_policy(data, false,
is_delete);
if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_NO_KEEP_DOMAIN))
return tomoyo_write_domain_keeper_policy(data, true, is_delete);
if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_INITIALIZE_DOMAIN))
return tomoyo_write_domain_initializer_policy(data, false,
is_delete);
if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_NO_INITIALIZE_DOMAIN))
return tomoyo_write_domain_initializer_policy(data, true,
is_delete);
if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_ALIAS))
return tomoyo_write_alias_policy(data, is_delete);
if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_ALLOW_READ))
return tomoyo_write_globally_readable_policy(data, is_delete);
if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_FILE_PATTERN))
return tomoyo_write_pattern_policy(data, is_delete);
if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_DENY_REWRITE))
return tomoyo_write_no_rewrite_policy(data, is_delete);
return -EINVAL;
}
/**
* tomoyo_read_exception_policy - Read exception policy.
*
* @head: Pointer to "struct tomoyo_io_buffer".
*
* Returns 0 on success, -EINVAL otherwise.
*
* Caller holds tomoyo_read_lock().
*/
static int tomoyo_read_exception_policy(struct tomoyo_io_buffer *head)
{
if (!head->read_eof) {
switch (head->read_step) {
case 0:
head->read_var2 = NULL;
head->read_step = 1;
case 1:
if (!tomoyo_read_domain_keeper_policy(head))
break;
head->read_var2 = NULL;
head->read_step = 2;
case 2:
if (!tomoyo_read_globally_readable_policy(head))
break;
head->read_var2 = NULL;
head->read_step = 3;
case 3:
head->read_var2 = NULL;
head->read_step = 4;
case 4:
if (!tomoyo_read_domain_initializer_policy(head))
break;
head->read_var2 = NULL;
head->read_step = 5;
case 5:
if (!tomoyo_read_alias_policy(head))
break;
head->read_var2 = NULL;
head->read_step = 6;
case 6:
head->read_var2 = NULL;
head->read_step = 7;
case 7:
if (!tomoyo_read_file_pattern(head))
break;
head->read_var2 = NULL;
head->read_step = 8;
case 8:
if (!tomoyo_read_no_rewrite_policy(head))
break;
head->read_var2 = NULL;
head->read_step = 9;
case 9:
head->read_eof = true;
break;
default:
return -EINVAL;
}
}
return 0;
}
/* path to policy loader */
static const char *tomoyo_loader = "/sbin/tomoyo-init";
/**
* tomoyo_policy_loader_exists - Check whether /sbin/tomoyo-init exists.
*
* Returns true if /sbin/tomoyo-init exists, false otherwise.
*/
static bool tomoyo_policy_loader_exists(void)
{
/*
* Don't activate MAC if the policy loader doesn't exist.
* If the initrd includes /sbin/init but real-root-dev has not
* mounted on / yet, activating MAC will block the system since
* policies are not loaded yet.
* Thus, let do_execve() call this function everytime.
*/
struct path path;
if (kern_path(tomoyo_loader, LOOKUP_FOLLOW, &path)) {
printk(KERN_INFO "Not activating Mandatory Access Control now "
"since %s doesn't exist.\n", tomoyo_loader);
return false;
}
path_put(&path);
return true;
}
/**
* tomoyo_load_policy - Run external policy loader to load policy.
*
* @filename: The program about to start.
*
* This function checks whether @filename is /sbin/init , and if so
* invoke /sbin/tomoyo-init and wait for the termination of /sbin/tomoyo-init
* and then continues invocation of /sbin/init.
* /sbin/tomoyo-init reads policy files in /etc/tomoyo/ directory and
* writes to /sys/kernel/security/tomoyo/ interfaces.
*
* Returns nothing.
*/
void tomoyo_load_policy(const char *filename)
{
char *argv[2];
char *envp[3];
if (tomoyo_policy_loaded)
return;
/*
* Check filename is /sbin/init or /sbin/tomoyo-start.
* /sbin/tomoyo-start is a dummy filename in case where /sbin/init can't
* be passed.
* You can create /sbin/tomoyo-start by
* "ln -s /bin/true /sbin/tomoyo-start".
*/
if (strcmp(filename, "/sbin/init") &&
strcmp(filename, "/sbin/tomoyo-start"))
return;
if (!tomoyo_policy_loader_exists())
return;
printk(KERN_INFO "Calling %s to load policy. Please wait.\n",
tomoyo_loader);
argv[0] = (char *) tomoyo_loader;
argv[1] = NULL;
envp[0] = "HOME=/";
envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
envp[2] = NULL;
call_usermodehelper(argv[0], argv, envp, 1);
printk(KERN_INFO "TOMOYO: 2.2.0 2009/04/01\n");
printk(KERN_INFO "Mandatory Access Control activated.\n");
tomoyo_policy_loaded = true;
{ /* Check all profiles currently assigned to domains are defined. */
struct tomoyo_domain_info *domain;
list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
const u8 profile = domain->profile;
if (tomoyo_profile_ptr[profile])
continue;
panic("Profile %u (used by '%s') not defined.\n",
profile, domain->domainname->name);
}
}
}
/**
* tomoyo_read_version: Get version.
*
* @head: Pointer to "struct tomoyo_io_buffer".
*
* Returns version information.
*/
static int tomoyo_read_version(struct tomoyo_io_buffer *head)
{
if (!head->read_eof) {
tomoyo_io_printf(head, "2.2.0");
head->read_eof = true;
}
return 0;
}
/**
* tomoyo_read_self_domain - Get the current process's domainname.
*
* @head: Pointer to "struct tomoyo_io_buffer".
*
* Returns the current process's domainname.
*/
static int tomoyo_read_self_domain(struct tomoyo_io_buffer *head)
{
if (!head->read_eof) {
/*
* tomoyo_domain()->domainname != NULL
* because every process belongs to a domain and
* the domain's name cannot be NULL.
*/
tomoyo_io_printf(head, "%s", tomoyo_domain()->domainname->name);
head->read_eof = true;
}
return 0;
}
/**
* tomoyo_open_control - open() for /sys/kernel/security/tomoyo/ interface.
*
* @type: Type of interface.
* @file: Pointer to "struct file".
*
* Associates policy handler and returns 0 on success, -ENOMEM otherwise.
*
* Caller acquires tomoyo_read_lock().
*/
static int tomoyo_open_control(const u8 type, struct file *file)
{
struct tomoyo_io_buffer *head = kzalloc(sizeof(*head), GFP_KERNEL);
if (!head)
return -ENOMEM;
mutex_init(&head->io_sem);
switch (type) {
case TOMOYO_DOMAINPOLICY:
/* /sys/kernel/security/tomoyo/domain_policy */
head->write = tomoyo_write_domain_policy;
head->read = tomoyo_read_domain_policy;
break;
case TOMOYO_EXCEPTIONPOLICY:
/* /sys/kernel/security/tomoyo/exception_policy */
head->write = tomoyo_write_exception_policy;
head->read = tomoyo_read_exception_policy;
break;
case TOMOYO_SELFDOMAIN:
/* /sys/kernel/security/tomoyo/self_domain */
head->read = tomoyo_read_self_domain;
break;
case TOMOYO_DOMAIN_STATUS:
/* /sys/kernel/security/tomoyo/.domain_status */
head->write = tomoyo_write_domain_profile;
head->read = tomoyo_read_domain_profile;
break;
case TOMOYO_PROCESS_STATUS:
/* /sys/kernel/security/tomoyo/.process_status */
head->write = tomoyo_write_pid;
head->read = tomoyo_read_pid;
break;
case TOMOYO_VERSION:
/* /sys/kernel/security/tomoyo/version */
head->read = tomoyo_read_version;
head->readbuf_size = 128;
break;
case TOMOYO_MEMINFO:
/* /sys/kernel/security/tomoyo/meminfo */
head->write = tomoyo_write_memory_quota;
head->read = tomoyo_read_memory_counter;
head->readbuf_size = 512;
break;
case TOMOYO_PROFILE:
/* /sys/kernel/security/tomoyo/profile */
head->write = tomoyo_write_profile;
head->read = tomoyo_read_profile;
break;
case TOMOYO_MANAGER:
/* /sys/kernel/security/tomoyo/manager */
head->write = tomoyo_write_manager_policy;
head->read = tomoyo_read_manager_policy;
break;
}
if (!(file->f_mode & FMODE_READ)) {
/*
* No need to allocate read_buf since it is not opened
* for reading.
*/
head->read = NULL;
} else {
if (!head->readbuf_size)
head->readbuf_size = 4096 * 2;
head->read_buf = kzalloc(head->readbuf_size, GFP_KERNEL);
if (!head->read_buf) {
kfree(head);
return -ENOMEM;
}
}
if (!(file->f_mode & FMODE_WRITE)) {
/*
* No need to allocate write_buf since it is not opened
* for writing.
*/
head->write = NULL;
} else if (head->write) {
head->writebuf_size = 4096 * 2;
head->write_buf = kzalloc(head->writebuf_size, GFP_KERNEL);
if (!head->write_buf) {
kfree(head->read_buf);
kfree(head);
return -ENOMEM;
}
}
head->reader_idx = tomoyo_read_lock();
file->private_data = head;
/*
* Call the handler now if the file is
* /sys/kernel/security/tomoyo/self_domain
* so that the user can use
* cat < /sys/kernel/security/tomoyo/self_domain"
* to know the current process's domainname.
*/
if (type == TOMOYO_SELFDOMAIN)
tomoyo_read_control(file, NULL, 0);
return 0;
}
/**
* tomoyo_read_control - read() for /sys/kernel/security/tomoyo/ interface.
*
* @file: Pointer to "struct file".
* @buffer: Poiner to buffer to write to.
* @buffer_len: Size of @buffer.
*
* Returns bytes read on success, negative value otherwise.
*
* Caller holds tomoyo_read_lock().
*/
static int tomoyo_read_control(struct file *file, char __user *buffer,
const int buffer_len)
{
int len = 0;
struct tomoyo_io_buffer *head = file->private_data;
char *cp;
if (!head->read)
return -ENOSYS;
if (mutex_lock_interruptible(&head->io_sem))
return -EINTR;
/* Call the policy handler. */
len = head->read(head);
if (len < 0)
goto out;
/* Write to buffer. */
len = head->read_avail;
if (len > buffer_len)
len = buffer_len;
if (!len)
goto out;
/* head->read_buf changes by some functions. */
cp = head->read_buf;
if (copy_to_user(buffer, cp, len)) {
len = -EFAULT;
goto out;
}
head->read_avail -= len;
memmove(cp, cp + len, head->read_avail);
out:
mutex_unlock(&head->io_sem);
return len;
}
/**
* tomoyo_write_control - write() for /sys/kernel/security/tomoyo/ interface.
*
* @file: Pointer to "struct file".
* @buffer: Pointer to buffer to read from.
* @buffer_len: Size of @buffer.
*
* Returns @buffer_len on success, negative value otherwise.
*
* Caller holds tomoyo_read_lock().
*/
static int tomoyo_write_control(struct file *file, const char __user *buffer,
const int buffer_len)
{
struct tomoyo_io_buffer *head = file->private_data;
int error = buffer_len;
int avail_len = buffer_len;
char *cp0 = head->write_buf;
if (!head->write)
return -ENOSYS;
if (!access_ok(VERIFY_READ, buffer, buffer_len))
return -EFAULT;
/* Don't allow updating policies by non manager programs. */
if (head->write != tomoyo_write_pid &&
head->write != tomoyo_write_domain_policy &&
!tomoyo_is_policy_manager())
return -EPERM;
if (mutex_lock_interruptible(&head->io_sem))
return -EINTR;
/* Read a line and dispatch it to the policy handler. */
while (avail_len > 0) {
char c;
if (head->write_avail >= head->writebuf_size - 1) {
error = -ENOMEM;
break;
} else if (get_user(c, buffer)) {
error = -EFAULT;
break;
}
buffer++;
avail_len--;
cp0[head->write_avail++] = c;
if (c != '\n')
continue;
cp0[head->write_avail - 1] = '\0';
head->write_avail = 0;
tomoyo_normalize_line(cp0);
head->write(head);
}
mutex_unlock(&head->io_sem);
return error;
}
/**
* tomoyo_close_control - close() for /sys/kernel/security/tomoyo/ interface.
*
* @file: Pointer to "struct file".
*
* Releases memory and returns 0.
*
* Caller looses tomoyo_read_lock().
*/
static int tomoyo_close_control(struct file *file)
{
struct tomoyo_io_buffer *head = file->private_data;
tomoyo_read_unlock(head->reader_idx);
/* Release memory used for policy I/O. */
kfree(head->read_buf);
head->read_buf = NULL;
kfree(head->write_buf);
head->write_buf = NULL;
kfree(head);
head = NULL;
file->private_data = NULL;
return 0;
}
/**
* tomoyo_open - open() for /sys/kernel/security/tomoyo/ interface.
*
* @inode: Pointer to "struct inode".
* @file: Pointer to "struct file".
*
* Returns 0 on success, negative value otherwise.
*/
static int tomoyo_open(struct inode *inode, struct file *file)
{
const int key = ((u8 *) file->f_path.dentry->d_inode->i_private)
- ((u8 *) NULL);
return tomoyo_open_control(key, file);
}
/**
* tomoyo_release - close() for /sys/kernel/security/tomoyo/ interface.
*
* @inode: Pointer to "struct inode".
* @file: Pointer to "struct file".
*
* Returns 0 on success, negative value otherwise.
*/
static int tomoyo_release(struct inode *inode, struct file *file)
{
return tomoyo_close_control(file);
}
/**
* tomoyo_read - read() for /sys/kernel/security/tomoyo/ interface.
*
* @file: Pointer to "struct file".
* @buf: Pointer to buffer.
* @count: Size of @buf.
* @ppos: Unused.
*
* Returns bytes read on success, negative value otherwise.
*/
static ssize_t tomoyo_read(struct file *file, char __user *buf, size_t count,
loff_t *ppos)
{
return tomoyo_read_control(file, buf, count);
}
/**
* tomoyo_write - write() for /sys/kernel/security/tomoyo/ interface.
*
* @file: Pointer to "struct file".
* @buf: Pointer to buffer.
* @count: Size of @buf.
* @ppos: Unused.
*
* Returns @count on success, negative value otherwise.
*/
static ssize_t tomoyo_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
return tomoyo_write_control(file, buf, count);
}
/*
* tomoyo_operations is a "struct file_operations" which is used for handling
* /sys/kernel/security/tomoyo/ interface.
*
* Some files under /sys/kernel/security/tomoyo/ directory accept open(O_RDWR).
* See tomoyo_io_buffer for internals.
*/
static const struct file_operations tomoyo_operations = {
.open = tomoyo_open,
.release = tomoyo_release,
.read = tomoyo_read,
.write = tomoyo_write,
};
/**
* tomoyo_create_entry - Create interface files under /sys/kernel/security/tomoyo/ directory.
*
* @name: The name of the interface file.
* @mode: The permission of the interface file.
* @parent: The parent directory.
* @key: Type of interface.
*
* Returns nothing.
*/
static void __init tomoyo_create_entry(const char *name, const mode_t mode,
struct dentry *parent, const u8 key)
{
securityfs_create_file(name, mode, parent, ((u8 *) NULL) + key,
&tomoyo_operations);
}
/**
* tomoyo_initerface_init - Initialize /sys/kernel/security/tomoyo/ interface.
*
* Returns 0.
*/
static int __init tomoyo_initerface_init(void)
{
struct dentry *tomoyo_dir;
/* Don't create securityfs entries unless registered. */
if (current_cred()->security != &tomoyo_kernel_domain)
return 0;
tomoyo_dir = securityfs_create_dir("tomoyo", NULL);
tomoyo_create_entry("domain_policy", 0600, tomoyo_dir,
TOMOYO_DOMAINPOLICY);
tomoyo_create_entry("exception_policy", 0600, tomoyo_dir,
TOMOYO_EXCEPTIONPOLICY);
tomoyo_create_entry("self_domain", 0400, tomoyo_dir,
TOMOYO_SELFDOMAIN);
tomoyo_create_entry(".domain_status", 0600, tomoyo_dir,
TOMOYO_DOMAIN_STATUS);
tomoyo_create_entry(".process_status", 0600, tomoyo_dir,
TOMOYO_PROCESS_STATUS);
tomoyo_create_entry("meminfo", 0600, tomoyo_dir,
TOMOYO_MEMINFO);
tomoyo_create_entry("profile", 0600, tomoyo_dir,
TOMOYO_PROFILE);
tomoyo_create_entry("manager", 0600, tomoyo_dir,
TOMOYO_MANAGER);
tomoyo_create_entry("version", 0400, tomoyo_dir,
TOMOYO_VERSION);
return 0;
}
fs_initcall(tomoyo_initerface_init);
