/* * 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 */