/*
* security/tomoyo/common.h
*
* Common functions for TOMOYO.
*
* Copyright (C) 2005-2009 NTT DATA CORPORATION
*
* Version: 2.2.0 2009/04/01
*
*/
#ifndef _SECURITY_TOMOYO_COMMON_H
#define _SECURITY_TOMOYO_COMMON_H
#include <linux/ctype.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/file.h>
#include <linux/kmod.h>
#include <linux/fs.h>
#include <linux/sched.h>
#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/list.h>
struct dentry;
struct vfsmount;
/*
* tomoyo_page_buffer is a structure which is used for holding a pathname
* obtained from "struct dentry" and "struct vfsmount" pair.
* As of now, it is 4096 bytes. If users complain that 4096 bytes is too small
* (because TOMOYO escapes non ASCII printable characters using \ooo format),
* we will make the buffer larger.
*/
struct tomoyo_page_buffer {
char buffer[4096];
};
/*
* tomoyo_path_info is a structure which is used for holding a string data
* used by TOMOYO.
* This structure has several fields for supporting pattern matching.
*
* (1) "name" is the '\0' terminated string data.
* (2) "hash" is full_name_hash(name, strlen(name)).
* This allows tomoyo_pathcmp() to compare by hash before actually compare
* using strcmp().
* (3) "const_len" is the length of the initial segment of "name" which
* consists entirely of non wildcard characters. In other words, the length
* which we can compare two strings using strncmp().
* (4) "is_dir" is a bool which is true if "name" ends with "/",
* false otherwise.
* TOMOYO distinguishes directory and non-directory. A directory ends with
* "/" and non-directory does not end with "/".
* (5) "is_patterned" is a bool which is true if "name" contains wildcard
* characters, false otherwise. This allows TOMOYO to use "hash" and
* strcmp() for string comparison if "is_patterned" is false.
* (6) "depth" is calculated using the number of "/" characters in "name".
* This allows TOMOYO to avoid comparing two pathnames which never match
* (e.g. whether "/var/www/html/index.html" matches "/tmp/sh-thd-\$").
*/
struct tomoyo_path_info {
const char *name;
u32 hash; /* = full_name_hash(name, strlen(name)) */
u16 const_len; /* = tomoyo_const_part_length(name) */
bool is_dir; /* = tomoyo_strendswith(name, "/") */
bool is_patterned; /* = tomoyo_path_contains_pattern(name) */
u16 depth; /* = tomoyo_path_depth(name) */
};
/*
* This is the max length of a token.
*
* A token consists of only ASCII printable characters.
* Non printable characters in a token is represented in \ooo style
* octal string. Thus, \ itself is represented as \\.
*/
#define TOMOYO_MAX_PATHNAME_LEN 4000
/*
* tomoyo_path_info_with_data is a structure which is used for holding a
* pathname obtained from "struct dentry" and "struct vfsmount" pair.
*
* "struct tomoyo_path_info_with_data" consists of "struct tomoyo_path_info"
* and buffer for the pathname, while "struct tomoyo_page_buffer" consists of
* buffer for the pathname only.
*
* "struct tomoyo_path_info_with_data" is intended to allow TOMOYO to release
* both "struct tomoyo_path_info" and buffer for the pathname by single kfree()
* so that we don't need to return two pointers to the caller. If the caller
* puts "struct tomoyo_path_info" on stack memory, we will be able to remove
* "struct tomoyo_path_info_with_data".
*/
struct tomoyo_path_info_with_data {
/* Keep "head" first, for this pointer is passed to tomoyo_free(). */
struct tomoyo_path_info head;
char barrier1[16]; /* Safeguard for overrun. */
char body[TOMOYO_MAX_PATHNAME_LEN];
char barrier2[16]; /* Safeguard for overrun. */
};
/*
* tomoyo_acl_info is a structure which is used for holding
*
* (1) "list" which is linked to the ->acl_info_list of
* "struct tomoyo_domain_info"
* (2) "type" which tells
* (a) type & 0x7F : type of the entry (either
* "struct tomoyo_single_path_acl_record" or
* "struct tomoyo_double_path_acl_record")
* (b) type & 0x80 : whether the entry is marked as "deleted".
*
* Packing "struct tomoyo_acl_info" allows
* "struct tomoyo_single_path_acl_record" to embed "u16" and
* "struct tomoyo_double_path_acl_record" to embed "u8"
* without enlarging their structure size.
*/
struct tomoyo_acl_info {
struct list_head list;
/*
* Type of this ACL entry.
*
* MSB is is_deleted flag.
*/
u8 type;
} __packed;
/* This ACL entry is deleted. */
#define TOMOYO_ACL_DELETED 0x80
/*
* tomoyo_domain_info is a structure which is used for holding permissions
* (e.g. "allow_read /lib/libc-2.5.so") given to each domain.
* It has following fields.
*
* (1) "list" which is linked to tomoyo_domain_list .
* (2) "acl_info_list" which is linked to "struct tomoyo_acl_info".
* (3) "domainname" which holds the name of the domain.
* (4) "profile" which remembers profile number assigned to this domain.
* (5) "is_deleted" is a bool which is true if this domain is marked as
* "deleted", false otherwise.
* (6) "quota_warned" is a bool which is used for suppressing warning message
* when learning mode learned too much entries.
* (7) "flags" which remembers this domain's attributes.
*
* A domain's lifecycle is an analogy of files on / directory.
* Multiple domains with the same domainname cannot be created (as with
* creating files with the same filename fails with -EEXIST).
* If a process reached a domain, that process can reside in that domain after
* that domain is marked as "deleted" (as with a process can access an already
* open()ed file after that file was unlink()ed).
*/
struct tomoyo_domain_info {
struct list_head list;
struct list_head acl_info_list;
/* Name of this domain. Never NULL. */
const struct tomoyo_path_info *domainname;
u8 profile; /* Profile number to use. */
bool is_deleted; /* Delete flag. */
bool quota_warned; /* Quota warnning flag. */
/* DOMAIN_FLAGS_*. Use tomoyo_set_domain_flag() to modify. */
u8 flags;
};
/* Profile number is an integer between 0 and 255. */
#define TOMOYO_MAX_PROFILES 256
/* Ignore "allow_read" directive in exception policy. */
#define TOMOYO_DOMAIN_FLAGS_IGNORE_GLOBAL_ALLOW_READ 1
/*
* This domain was unable to create a new domain at tomoyo_find_next_domain()
* because the name of the domain to be created was too long or
* it could not allocate memory.
* More than one process continued execve() without domain transition.
*/
#define TOMOYO_DOMAIN_FLAGS_TRANSITION_FAILED 2
/*
* tomoyo_single_path_acl_record is a structure which is used for holding an
* entry with one pathname operation (e.g. open(), mkdir()).
* It has following fields.
*
* (1) "head" which is a "struct tomoyo_acl_info".
* (2) "perm" which is a bitmask of permitted operations.
* (3) "filename" is the pathname.
*
* Directives held by this structure are "allow_read/write", "allow_execute",
* "allow_read", "allow_write", "allow_create", "allow_unlink", "allow_mkdir",
* "allow_rmdir", "allow_mkfifo", "allow_mksock", "allow_mkblock",
* "allow_mkchar", "allow_truncate", "allow_symlink" and "allow_rewrite".
*/
struct tomoyo_single_path_acl_record {
struct tomoyo_acl_info head; /* type = TOMOYO_TYPE_SINGLE_PATH_ACL */
u16 perm;
/* Pointer to single pathname. */
const struct tomoyo_path_info *filename;
};
/*
* tomoyo_double_path_acl_record is a structure which is used for holding an
* entry with two pathnames operation (i.e. link() and rename()).
* It has following fields.
*
* (1) "head" which is a "struct tomoyo_acl_info".
* (2) "perm" which is a bitmask of permitted operations.
* (3) "filename1" is the source/old pathname.
* (4) "filename2" is the destination/new pathname.
*
* Directives held by this structure are "allow_rename" and "allow_link".
*/
struct tomoyo_double_path_acl_record {
struct tomoyo_acl_info head; /* type = TOMOYO_TYPE_DOUBLE_PATH_ACL */
u8 perm;
/* Pointer to single pathname. */
const struct tomoyo_path_info *filename1;
/* Pointer to single pathname. */
const struct tomoyo_path_info *filename2;
};
/* Keywords for ACLs. */
#define TOMOYO_KEYWORD_ALIAS "alias "
#define TOMOYO_KEYWORD_ALLOW_READ "allow_read "
#define TOMOYO_KEYWORD_DELETE "delete "
#define TOMOYO_KEYWORD_DENY_REWRITE "deny_rewrite "
#define TOMOYO_KEYWORD_FILE_PATTERN "file_pattern "
#define TOMOYO_KEYWORD_INITIALIZE_DOMAIN "initialize_domain "
#define TOMOYO_KEYWORD_KEEP_DOMAIN "keep_domain "
#define TOMOYO_KEYWORD_NO_INITIALIZE_DOMAIN "no_initialize_domain "
#define TOMOYO_KEYWORD_NO_KEEP_DOMAIN "no_keep_domain "
#define TOMOYO_KEYWORD_SELECT "select "
#define TOMOYO_KEYWORD_USE_PROFILE "use_profile "
#define TOMOYO_KEYWORD_IGNORE_GLOBAL_ALLOW_READ "ignore_global_allow_read"
/* A domain definition starts with <kernel>. */
#define TOMOYO_ROOT_NAME "<kernel>"
#define TOMOYO_ROOT_NAME_LEN (sizeof(TOMOYO_ROOT_NAME) - 1)
/* Index numbers for Access Controls. */
#define TOMOYO_MAC_FOR_FILE 0 /* domain_policy.conf */
#define TOMOYO_MAX_ACCEPT_ENTRY 1
#define TOMOYO_VERBOSE 2
#define TOMOYO_MAX_CONTROL_INDEX 3
/*
* tomoyo_io_buffer is a structure which is used for reading and modifying
* configuration via /sys/kernel/security/tomoyo/ interface.
* It has many fields. ->read_var1 , ->read_var2 , ->write_var1 are used as
* cursors.
*
* Since the content of /sys/kernel/security/tomoyo/domain_policy is a list of
* "struct tomoyo_domain_info" entries and each "struct tomoyo_domain_info"
* entry has a list of "struct tomoyo_acl_info", we need two cursors when
* reading (one is for traversing tomoyo_domain_list and the other is for
* traversing "struct tomoyo_acl_info"->acl_info_list ).
*
* If a line written to /sys/kernel/security/tomoyo/domain_policy starts with
* "select ", TOMOYO seeks the cursor ->read_var1 and ->write_var1 to the
* domain with the domainname specified by the rest of that line (NULL is set
* if seek failed).
* If a line written to /sys/kernel/security/tomoyo/domain_policy starts with
* "delete ", TOMOYO deletes an entry or a domain specified by the rest of that
* line (->write_var1 is set to NULL if a domain was deleted).
* If a line written to /sys/kernel/security/tomoyo/domain_policy starts with
* neither "select " nor "delete ", an entry or a domain specified by that line
* is appended.
*/
struct tomoyo_io_buffer {
int (*read) (struct tomoyo_io_buffer *);
int (*write) (struct tomoyo_io_buffer *);
/* Exclusive lock for this structure. */
struct mutex io_sem;
/* The position currently reading from. */
struct list_head *read_var1;
/* Extra variables for reading. */
struct list_head *read_var2;
/* The position currently writing to. */
struct tomoyo_domain_info *write_var1;
/* The step for reading. */
int read_step;
/* Buffer for reading. */
char *read_buf;
/* EOF flag for reading. */
bool read_eof;
/* Read domain ACL of specified PID? */
bool read_single_domain;
/* Extra variable for reading. */
u8 read_bit;
/* Bytes available for reading. */
int read_avail;
/* Size of read buffer. */
int readbuf_size;
/* Buffer for writing. */
char *write_buf;
/* Bytes available for writing. */
int write_avail;
/* Size of write buffer. */
int writebuf_size;
};
/* Check whether the domain has too many ACL entries to hold. */
bool tomoyo_domain_quota_is_ok(struct tomoyo_domain_info * const domain);
/* Transactional sprintf() for policy dump. */
bool tomoyo_io_printf(struct tomoyo_io_buffer *head, const char *fmt, ...)
__attribute__ ((format(printf, 2, 3)));
/* Check whether the domainname is correct. */
bool tomoyo_is_correct_domain(const unsigned char *domainname,
const char *function);
/* Check whether the token is correct. */
bool tomoyo_is_correct_path(const char *filename, const s8 start_type,
const s8 pattern_type, const s8 end_type,
const char *function);
/* Check whether the token can be a domainname. */
bool tomoyo_is_domain_def(const unsigned char *buffer);
/* Check whether the given filename matches the given pattern. */
bool tomoyo_path_matches_pattern(const struct tomoyo_path_info *filename,
const struct tomoyo_path_info *pattern);
/* Read "alias" entry in exception policy. */
bool tomoyo_read_alias_policy(struct tomoyo_io_buffer *head);
/*
* Read "initialize_domain" and "no_initialize_domain" entry
* in exception policy.
*/
bool tomoyo_read_domain_initializer_policy(struct tomoyo_io_buffer *head);
/* Read "keep_domain" and "no_keep_domain" entry in exception policy. */
bool tomoyo_read_domain_keeper_policy(struct tomoyo_io_buffer *head);
/* Read "file_pattern" entry in exception policy. */
bool tomoyo_read_file_pattern(struct tomoyo_io_buffer *head);
/* Read "allow_read" entry in exception policy. */
bool tomoyo_read_globally_readable_policy(struct tomoyo_io_buffer *head);
/* Read "deny_rewrite" entry in exception policy. */
bool tomoyo_read_no_rewrite_policy(struct tomoyo_io_buffer *head);
/* Write domain policy violation warning message to console? */
bool tomoyo_verbose_mode(const struct tomoyo_domain_info *domain);
/* Convert double path operation to operation name. */
const char *tomoyo_dp2keyword(const u8 operation);
/* Get the last component of the given domainname. */
const char *tomoyo_get_last_name(const struct tomoyo_domain_info *domain);
/* Get warning message. */
const char *tomoyo_get_msg(const bool is_enforce);
/* Convert single path operation to operation name. */
const char *tomoyo_sp2keyword(const u8 operation);
/* Create "alias" entry in exception policy. */
int tomoyo_write_alias_policy(char *data, const bool is_delete);
/*
* Create "initialize_domain" and "no_initialize_domain" entry
* in exception policy.
*/
int tomoyo_write_domain_initializer_policy(char *data, const bool is_not,
const bool is_delete);
/* Create "keep_domain" and "no_keep_domain" entry in exception policy. */
int tomoyo_write_domain_keeper_policy(char *data, const bool is_not,
const bool is_delete);
/*
* Create "allow_read/write", "allow_execute", "allow_read", "allow_write",
* "allow_create", "allow_unlink", "allow_mkdir", "allow_rmdir",
* "allow_mkfifo", "allow_mksock", "allow_mkblock", "allow_mkchar",
* "allow_truncate", "allow_symlink", "allow_rewrite", "allow_rename" and
* "allow_link" entry in domain policy.
*/
int tomoyo_write_file_policy(char *data, struct tomoyo_domain_info *domain,
const bool is_delete);
/* Create "allow_read" entry in exception policy. */
int tomoyo_write_globally_readable_policy(char *data, const bool is_delete);
/* Create "deny_rewrite" entry in exception policy. */
int tomoyo_write_no_rewrite_policy(char *data, const bool is_delete);
/* Create "file_pattern" entry in exception policy. */
int tomoyo_write_pattern_policy(char *data, const bool is_delete);
/* Find a domain by the given name. */
struct tomoyo_domain_info *tomoyo_find_domain(const char *domainname);
/* Find or create a domain by the given name. */
struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char *
domainname,
const u8 profile);
/* Check mode for specified functionality. */
unsigned int tomoyo_check_flags(const struct tomoyo_domain_info *domain,
const u8 index);
/* Allocate memory for structures. */
void *tomoyo_alloc_acl_element(const u8 acl_type);
/* Fill in "struct tomoyo_path_info" members. */
void tomoyo_fill_path_info(struct tomoyo_path_info *ptr);
/* Run policy loader when /sbin/init starts. */
void tomoyo_load_policy(const char *filename);
/* Change "struct tomoyo_domain_info"->flags. */
void tomoyo_set_domain_flag(struct tomoyo_domain_info *domain,
const bool is_delete, const u8 flags);
/* strcmp() for "struct tomoyo_path_info" structure. */
static inline bool tomoyo_pathcmp(const struct tomoyo_path_info *a,
const struct tomoyo_path_info *b)
{
return a->hash != b->hash || strcmp(a->name, b->name);
}
/* Get type of an ACL entry. */
static inline u8 tomoyo_acl_type1(struct tomoyo_acl_info *ptr)
{
return ptr->type & ~TOMOYO_ACL_DELETED;
}
/* Get type of an ACL entry. */
static inline u8 tomoyo_acl_type2(struct tomoyo_acl_info *ptr)
{
return ptr->type;
}
/**
* tomoyo_is_valid - Check whether the character is a valid char.
*
* @c: The character to check.
*
* Returns true if @c is a valid character, false otherwise.
*/
static inline bool tomoyo_is_valid(const unsigned char c)
{
return c > ' ' && c < 127;
}
/**
* tomoyo_is_invalid - Check whether the character is an invalid char.
*
* @c: The character to check.
*
* Returns true if @c is an invalid character, false otherwise.
*/
static inline bool tomoyo_is_invalid(const unsigned char c)
{
return c && (c <= ' ' || c >= 127);
}
/* The list for "struct tomoyo_domain_info". */
extern struct list_head tomoyo_domain_list;
extern struct rw_semaphore tomoyo_domain_list_lock;
/* Lock for domain->acl_info_list. */
extern struct rw_semaphore tomoyo_domain_acl_info_list_lock;
/* Has /sbin/init started? */
extern bool tomoyo_policy_loaded;
/* The kernel's domain. */
extern struct tomoyo_domain_info tomoyo_kernel_domain;
/**
* list_for_each_cookie - iterate over a list with cookie.
* @pos: the &struct list_head to use as a loop cursor.
* @cookie: the &struct list_head to use as a cookie.
* @head: the head for your list.
*
* Same with list_for_each() except that this primitive uses @cookie
* so that we can continue iteration.
* @cookie must be NULL when iteration starts, and @cookie will become
* NULL when iteration finishes.
*/
#define list_for_each_cookie(pos, cookie, head) \
for (({ if (!cookie) \
cookie = head; }), \
pos = (cookie)->next; \
prefetch(pos->next), pos != (head) || ((cookie) = NULL); \
(cookie) = pos, pos = pos->next)
#endif /* !defined(_SECURITY_TOMOYO_COMMON_H) */
