linux/security/smack/smack.h

215 lines
5.5 KiB
C

/*
* Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 2.
*
* Author:
* Casey Schaufler <casey@schaufler-ca.com>
*
*/
#ifndef _SECURITY_SMACK_H
#define _SECURITY_SMACK_H
#include <linux/capability.h>
#include <linux/spinlock.h>
#include <linux/security.h>
#include <net/netlabel.h>
/*
* Why 23? CIPSO is constrained to 30, so a 32 byte buffer is
* bigger than can be used, and 24 is the next lower multiple
* of 8, and there are too many issues if there isn't space set
* aside for the terminating null byte.
*/
#define SMK_MAXLEN 23
#define SMK_LABELLEN (SMK_MAXLEN+1)
struct superblock_smack {
char *smk_root;
char *smk_floor;
char *smk_hat;
char *smk_default;
int smk_initialized;
spinlock_t smk_sblock; /* for initialization */
};
struct socket_smack {
char *smk_out; /* outbound label */
char *smk_in; /* inbound label */
char smk_packet[SMK_LABELLEN]; /* TCP peer label */
};
/*
* Inode smack data
*/
struct inode_smack {
char *smk_inode; /* label of the fso */
struct mutex smk_lock; /* initialization lock */
int smk_flags; /* smack inode flags */
};
#define SMK_INODE_INSTANT 0x01 /* inode is instantiated */
/*
* A label access rule.
*/
struct smack_rule {
char *smk_subject;
char *smk_object;
int smk_access;
};
/*
* An entry in the table of permitted label accesses.
*/
struct smk_list_entry {
struct smk_list_entry *smk_next;
struct smack_rule smk_rule;
};
/*
* An entry in the table mapping smack values to
* CIPSO level/category-set values.
*/
struct smack_cipso {
int smk_level;
char smk_catset[SMK_LABELLEN];
};
/*
* This is the repository for labels seen so that it is
* not necessary to keep allocating tiny chuncks of memory
* and so that they can be shared.
*
* Labels are never modified in place. Anytime a label
* is imported (e.g. xattrset on a file) the list is checked
* for it and it is added if it doesn't exist. The address
* is passed out in either case. Entries are added, but
* never deleted.
*
* Since labels are hanging around anyway it doesn't
* hurt to maintain a secid for those awkward situations
* where kernel components that ought to use LSM independent
* interfaces don't. The secid should go away when all of
* these components have been repaired.
*
* If there is a cipso value associated with the label it
* gets stored here, too. This will most likely be rare as
* the cipso direct mapping in used internally.
*/
struct smack_known {
struct smack_known *smk_next;
char smk_known[SMK_LABELLEN];
u32 smk_secid;
struct smack_cipso *smk_cipso;
spinlock_t smk_cipsolock; /* for changing cipso map */
};
/*
* Mount options
*/
#define SMK_FSDEFAULT "smackfsdef="
#define SMK_FSFLOOR "smackfsfloor="
#define SMK_FSHAT "smackfshat="
#define SMK_FSROOT "smackfsroot="
/*
* xattr names
*/
#define XATTR_SMACK_SUFFIX "SMACK64"
#define XATTR_SMACK_IPIN "SMACK64IPIN"
#define XATTR_SMACK_IPOUT "SMACK64IPOUT"
#define XATTR_NAME_SMACK XATTR_SECURITY_PREFIX XATTR_SMACK_SUFFIX
#define XATTR_NAME_SMACKIPIN XATTR_SECURITY_PREFIX XATTR_SMACK_IPIN
#define XATTR_NAME_SMACKIPOUT XATTR_SECURITY_PREFIX XATTR_SMACK_IPOUT
/*
* smackfs macic number
*/
#define SMACK_MAGIC 0x43415d53 /* "SMAC" */
/*
* A limit on the number of entries in the lists
* makes some of the list administration easier.
*/
#define SMACK_LIST_MAX 10000
/*
* CIPSO defaults.
*/
#define SMACK_CIPSO_DOI_DEFAULT 3 /* Historical */
#define SMACK_CIPSO_DIRECT_DEFAULT 250 /* Arbitrary */
#define SMACK_CIPSO_MAXCATVAL 63 /* Bigger gets harder */
#define SMACK_CIPSO_MAXLEVEL 255 /* CIPSO 2.2 standard */
#define SMACK_CIPSO_MAXCATNUM 239 /* CIPSO 2.2 standard */
/*
* Just to make the common cases easier to deal with
*/
#define MAY_ANY (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
#define MAY_ANYREAD (MAY_READ | MAY_EXEC)
#define MAY_ANYWRITE (MAY_WRITE | MAY_APPEND)
#define MAY_READWRITE (MAY_READ | MAY_WRITE)
#define MAY_NOT 0
/*
* These functions are in smack_lsm.c
*/
struct inode_smack *new_inode_smack(char *);
/*
* These functions are in smack_access.c
*/
int smk_access(char *, char *, int);
int smk_curacc(char *, u32);
int smack_to_cipso(const char *, struct smack_cipso *);
void smack_from_cipso(u32, char *, char *);
char *smack_from_secid(const u32);
char *smk_import(const char *, int);
struct smack_known *smk_import_entry(const char *, int);
u32 smack_to_secid(const char *);
/*
* Shared data.
*/
extern int smack_cipso_direct;
extern int smack_net_nltype;
extern char *smack_net_ambient;
extern struct smack_known *smack_known;
extern struct smack_known smack_known_floor;
extern struct smack_known smack_known_hat;
extern struct smack_known smack_known_huh;
extern struct smack_known smack_known_invalid;
extern struct smack_known smack_known_star;
extern struct smack_known smack_known_unset;
extern struct smk_list_entry *smack_list;
extern struct security_operations smack_ops;
/*
* Stricly for CIPSO level manipulation.
* Set the category bit number in a smack label sized buffer.
*/
static inline void smack_catset_bit(int cat, char *catsetp)
{
if (cat > SMK_LABELLEN * 8)
return;
catsetp[(cat - 1) / 8] |= 0x80 >> ((cat - 1) % 8);
}
/*
* Present a pointer to the smack label in an inode blob.
*/
static inline char *smk_of_inode(const struct inode *isp)
{
struct inode_smack *sip = isp->i_security;
return sip->smk_inode;
}
#endif /* _SECURITY_SMACK_H */