[deliverable/linux.git] / security / smack / smack.h

/*
 * 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 <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)

/*
 * How many kinds of access are there?
 * Here's your answer.
 */
#define SMK_ACCESSDASH	'-'
#define SMK_ACCESSLOW	"rwxa"
#define SMK_ACCESSKINDS	(sizeof(SMK_ACCESSLOW) - 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;

/*
 * 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 */
Commit	Line	Data
e114e473 CS	1	/*
	2	* Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com>
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License as published by
	6	* the Free Software Foundation, version 2.
	7	*
	8	* Author:
	9	* Casey Schaufler <casey@schaufler-ca.com>
	10	*
	11	*/
	12
	13	#ifndef _SECURITY_SMACK_H
	14	#define _SECURITY_SMACK_H
	15
	16	#include <linux/capability.h>
	17	#include <linux/spinlock.h>
	18	#include <net/netlabel.h>
	19
	20	/*
	21	* Why 23? CIPSO is constrained to 30, so a 32 byte buffer is
	22	* bigger than can be used, and 24 is the next lower multiple
	23	* of 8, and there are too many issues if there isn't space set
	24	* aside for the terminating null byte.
	25	*/
	26	#define SMK_MAXLEN 23
	27	#define SMK_LABELLEN (SMK_MAXLEN+1)
	28
	29	/*
	30	* How many kinds of access are there?
	31	* Here's your answer.
	32	*/
	33	#define SMK_ACCESSDASH '-'
	34	#define SMK_ACCESSLOW "rwxa"
	35	#define SMK_ACCESSKINDS (sizeof(SMK_ACCESSLOW) - 1)
	36
	37	struct superblock_smack {
	38	char *smk_root;
	39	char *smk_floor;
	40	char *smk_hat;
	41	char *smk_default;
	42	int smk_initialized;
	43	spinlock_t smk_sblock; /* for initialization */
	44	};
	45
	46	struct socket_smack {
	47	char smk_out; / outbound label */
	48	char smk_in; / inbound label */
	49	char smk_packet[SMK_LABELLEN]; /* TCP peer label */
	50	};
	51
	52	/*
	53	* Inode smack data
	54	*/
	55	struct inode_smack {
	56	char smk_inode; / label of the fso */
	57	struct mutex smk_lock; /* initialization lock */
	58	int smk_flags; /* smack inode flags */
	59	};
	60
	61	#define SMK_INODE_INSTANT 0x01 /* inode is instantiated */
	62
	63	/*
	64	* A label access rule.
65	*/
66	struct smack_rule {
67	char *smk_subject;
68	char *smk_object;
69	int smk_access;
70	};
71
72	/*
73	* An entry in the table of permitted label accesses.
74	*/
75	struct smk_list_entry {
76	struct smk_list_entry *smk_next;
77	struct smack_rule smk_rule;
78	};
79
80	/*
81	* An entry in the table mapping smack values to
82	* CIPSO level/category-set values.
83	*/
84	struct smack_cipso {
85	int smk_level;
86	char smk_catset[SMK_LABELLEN];
87	};
88
89	/*
90	* This is the repository for labels seen so that it is
91	* not necessary to keep allocating tiny chuncks of memory
92	* and so that they can be shared.
93	*
94	* Labels are never modified in place. Anytime a label
95	* is imported (e.g. xattrset on a file) the list is checked
96	* for it and it is added if it doesn't exist. The address
97	* is passed out in either case. Entries are added, but
98	* never deleted.
99	*
100	* Since labels are hanging around anyway it doesn't
101	* hurt to maintain a secid for those awkward situations
102	* where kernel components that ought to use LSM independent
103	* interfaces don't. The secid should go away when all of
104	* these components have been repaired.
105	*
106	* If there is a cipso value associated with the label it
107	* gets stored here, too. This will most likely be rare as
108	* the cipso direct mapping in used internally.
109	*/
110	struct smack_known {
111	struct smack_known *smk_next;
112	char smk_known[SMK_LABELLEN];
113	u32 smk_secid;
114	struct smack_cipso *smk_cipso;
115	spinlock_t smk_cipsolock; /* for changing cipso map */
116	};
117
118	/*
119	* Mount options
120	*/
121	#define SMK_FSDEFAULT "smackfsdef="
122	#define SMK_FSFLOOR "smackfsfloor="
123	#define SMK_FSHAT "smackfshat="
124	#define SMK_FSROOT "smackfsroot="
125
126	/*
127	* xattr names
128	*/
129	#define XATTR_SMACK_SUFFIX "SMACK64"
130	#define XATTR_SMACK_IPIN "SMACK64IPIN"
131	#define XATTR_SMACK_IPOUT "SMACK64IPOUT"
132	#define XATTR_NAME_SMACK XATTR_SECURITY_PREFIX XATTR_SMACK_SUFFIX
133	#define XATTR_NAME_SMACKIPIN XATTR_SECURITY_PREFIX XATTR_SMACK_IPIN
134	#define XATTR_NAME_SMACKIPOUT XATTR_SECURITY_PREFIX XATTR_SMACK_IPOUT
135
136	/*
137	* smackfs macic number
138	*/
139	#define SMACK_MAGIC 0x43415d53 /* "SMAC" */
140
141	/*
142	* A limit on the number of entries in the lists
143	* makes some of the list administration easier.
144	*/
145	#define SMACK_LIST_MAX 10000
146
147	/*
148	* CIPSO defaults.
149	*/
150	#define SMACK_CIPSO_DOI_DEFAULT 3 /* Historical */
151	#define SMACK_CIPSO_DIRECT_DEFAULT 250 /* Arbitrary */
152	#define SMACK_CIPSO_MAXCATVAL 63 /* Bigger gets harder */
153	#define SMACK_CIPSO_MAXLEVEL 255 /* CIPSO 2.2 standard */
154	#define SMACK_CIPSO_MAXCATNUM 239 /* CIPSO 2.2 standard */
155
156	/*
157	* Just to make the common cases easier to deal with
158	*/
159	#define MAY_ANY (MAY_READ \| MAY_WRITE \| MAY_APPEND \| MAY_EXEC)
160	#define MAY_ANYREAD (MAY_READ \| MAY_EXEC)
161	#define MAY_ANYWRITE (MAY_WRITE \| MAY_APPEND)
162	#define MAY_READWRITE (MAY_READ \| MAY_WRITE)
163	#define MAY_NOT 0
164
165	/*
166	* These functions are in smack_lsm.c
167	*/
168	struct inode_smack new_inode_smack(char );
169
170	/*
171	* These functions are in smack_access.c
172	*/
173	int smk_access(char , char , int);
174	int smk_curacc(char *, u32);
175	int smack_to_cipso(const char , struct smack_cipso );
176	void smack_from_cipso(u32, char , char );
177	char *smack_from_secid(const u32);
178	char smk_import(const char , int);
179	struct smack_known smk_import_entry(const char , int);
180	u32 smack_to_secid(const char *);
181
182	/*
183	* Shared data.
184	*/
185	extern int smack_cipso_direct;
186	extern int smack_net_nltype;
187	extern char *smack_net_ambient;
188
189	extern struct smack_known *smack_known;
190	extern struct smack_known smack_known_floor;
191	extern struct smack_known smack_known_hat;
192	extern struct smack_known smack_known_huh;
193	extern struct smack_known smack_known_invalid;
194	extern struct smack_known smack_known_star;
195	extern struct smack_known smack_known_unset;
196
197	extern struct smk_list_entry *smack_list;
198
199	/*
200	* Stricly for CIPSO level manipulation.
201	* Set the category bit number in a smack label sized buffer.
202	*/
203	static inline void smack_catset_bit(int cat, char *catsetp)
204	{
205	if (cat > SMK_LABELLEN * 8)
206	return;
207
208	catsetp[(cat - 1) / 8] \|= 0x80 >> ((cat - 1) % 8);
209	}
210
211	/*
212	* Present a pointer to the smack label in an inode blob.
213	*/
214	static inline char smk_of_inode(const struct inode isp)
215	{
216	struct inode_smack *sip = isp->i_security;
217	return sip->smk_inode;
218	}
219
220	#endif /* _SECURITY_SMACK_H */