diff options
Diffstat (limited to 'security/smack/smack.h')
| -rw-r--r-- | security/smack/smack.h | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/security/smack/smack.h b/security/smack/smack.h new file mode 100644 index 00000000000..a21a0e907ab --- /dev/null +++ b/security/smack/smack.h @@ -0,0 +1,220 @@ +/* + * 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 */ |