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 <linux/security.h> 19#include <linux/in.h> 20#include <net/netlabel.h> 21#include <linux/list.h> 22#include <linux/rculist.h> 23 24/* 25 * Why 23? CIPSO is constrained to 30, so a 32 byte buffer is 26 * bigger than can be used, and 24 is the next lower multiple 27 * of 8, and there are too many issues if there isn't space set 28 * aside for the terminating null byte. 29 */ 30#define SMK_MAXLEN 23 31#define SMK_LABELLEN (SMK_MAXLEN+1) 32 33struct superblock_smack { 34 char *smk_root; 35 char *smk_floor; 36 char *smk_hat; 37 char *smk_default; 38 int smk_initialized; 39 spinlock_t smk_sblock; /* for initialization */ 40}; 41 42struct socket_smack { 43 char *smk_out; /* outbound label */ 44 char *smk_in; /* inbound label */ 45 char smk_packet[SMK_LABELLEN]; /* TCP peer label */ 46}; 47 48/* 49 * Inode smack data 50 */ 51struct inode_smack { 52 char *smk_inode; /* label of the fso */ 53 struct mutex smk_lock; /* initialization lock */ 54 int smk_flags; /* smack inode flags */ 55}; 56 57#define SMK_INODE_INSTANT 0x01 /* inode is instantiated */ 58 59/* 60 * A label access rule. 61 */ 62struct smack_rule { 63 struct list_head list; 64 char *smk_subject; 65 char *smk_object; 66 int smk_access; 67}; 68 69/* 70 * An entry in the table mapping smack values to 71 * CIPSO level/category-set values. 72 */ 73struct smack_cipso { 74 int smk_level; 75 char smk_catset[SMK_LABELLEN]; 76}; 77 78/* 79 * An entry in the table identifying hosts. 80 */ 81struct smk_netlbladdr { 82 struct list_head list; 83 struct sockaddr_in smk_host; /* network address */ 84 struct in_addr smk_mask; /* network mask */ 85 char *smk_label; /* label */ 86}; 87 88/* 89 * This is the repository for labels seen so that it is 90 * not necessary to keep allocating tiny chuncks of memory 91 * and so that they can be shared. 92 * 93 * Labels are never modified in place. Anytime a label 94 * is imported (e.g. xattrset on a file) the list is checked 95 * for it and it is added if it doesn't exist. The address 96 * is passed out in either case. Entries are added, but 97 * never deleted. 98 * 99 * Since labels are hanging around anyway it doesn't 100 * hurt to maintain a secid for those awkward situations 101 * where kernel components that ought to use LSM independent 102 * interfaces don't. The secid should go away when all of 103 * these components have been repaired. 104 * 105 * If there is a cipso value associated with the label it 106 * gets stored here, too. This will most likely be rare as 107 * the cipso direct mapping in used internally. 108 */ 109struct smack_known { 110 struct list_head list; 111 char smk_known[SMK_LABELLEN]; 112 u32 smk_secid; 113 struct smack_cipso *smk_cipso; 114 spinlock_t smk_cipsolock; /* for changing cipso map */ 115}; 116 117/* 118 * Mount options 119 */ 120#define SMK_FSDEFAULT "smackfsdef=" 121#define SMK_FSFLOOR "smackfsfloor=" 122#define SMK_FSHAT "smackfshat=" 123#define SMK_FSROOT "smackfsroot=" 124 125/* 126 * xattr names 127 */ 128#define XATTR_SMACK_SUFFIX "SMACK64" 129#define XATTR_SMACK_IPIN "SMACK64IPIN" 130#define XATTR_SMACK_IPOUT "SMACK64IPOUT" 131#define XATTR_NAME_SMACK XATTR_SECURITY_PREFIX XATTR_SMACK_SUFFIX 132#define XATTR_NAME_SMACKIPIN XATTR_SECURITY_PREFIX XATTR_SMACK_IPIN 133#define XATTR_NAME_SMACKIPOUT XATTR_SECURITY_PREFIX XATTR_SMACK_IPOUT 134 135#define SMACK_CIPSO_OPTION "-CIPSO" 136 137/* 138 * How communications on this socket are treated. 139 * Usually it's determined by the underlying netlabel code 140 * but there are certain cases, including single label hosts 141 * and potentially single label interfaces for which the 142 * treatment can not be known in advance. 143 * 144 * The possibility of additional labeling schemes being 145 * introduced in the future exists as well. 146 */ 147#define SMACK_UNLABELED_SOCKET 0 148#define SMACK_CIPSO_SOCKET 1 149 150/* 151 * smackfs magic number 152 * smackfs macic number 153 */ 154#define SMACK_MAGIC 0x43415d53 /* "SMAC" */ 155 156/* 157 * A limit on the number of entries in the lists 158 * makes some of the list administration easier. 159 */ 160#define SMACK_LIST_MAX 10000 161 162/* 163 * CIPSO defaults. 164 */ 165#define SMACK_CIPSO_DOI_DEFAULT 3 /* Historical */ 166#define SMACK_CIPSO_DOI_INVALID -1 /* Not a DOI */ 167#define SMACK_CIPSO_DIRECT_DEFAULT 250 /* Arbitrary */ 168#define SMACK_CIPSO_MAXCATVAL 63 /* Bigger gets harder */ 169#define SMACK_CIPSO_MAXLEVEL 255 /* CIPSO 2.2 standard */ 170#define SMACK_CIPSO_MAXCATNUM 239 /* CIPSO 2.2 standard */ 171 172/* 173 * Just to make the common cases easier to deal with 174 */ 175#define MAY_ANY (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC) 176#define MAY_ANYREAD (MAY_READ | MAY_EXEC) 177#define MAY_ANYWRITE (MAY_WRITE | MAY_APPEND) 178#define MAY_READWRITE (MAY_READ | MAY_WRITE) 179#define MAY_NOT 0 180 181/* 182 * These functions are in smack_lsm.c 183 */ 184struct inode_smack *new_inode_smack(char *); 185 186/* 187 * These functions are in smack_access.c 188 */ 189int smk_access(char *, char *, int); 190int smk_curacc(char *, u32); 191int smack_to_cipso(const char *, struct smack_cipso *); 192void smack_from_cipso(u32, char *, char *); 193char *smack_from_secid(const u32); 194char *smk_import(const char *, int); 195struct smack_known *smk_import_entry(const char *, int); 196u32 smack_to_secid(const char *); 197 198/* 199 * Shared data. 200 */ 201extern int smack_cipso_direct; 202extern char *smack_net_ambient; 203extern char *smack_onlycap; 204extern const char *smack_cipso_option; 205 206extern struct smack_known smack_known_floor; 207extern struct smack_known smack_known_hat; 208extern struct smack_known smack_known_huh; 209extern struct smack_known smack_known_invalid; 210extern struct smack_known smack_known_star; 211extern struct smack_known smack_known_web; 212 213extern struct list_head smack_known_list; 214extern struct list_head smack_rule_list; 215extern struct list_head smk_netlbladdr_list; 216 217extern struct security_operations smack_ops; 218 219/* 220 * Stricly for CIPSO level manipulation. 221 * Set the category bit number in a smack label sized buffer. 222 */ 223static inline void smack_catset_bit(int cat, char *catsetp) 224{ 225 if (cat > SMK_LABELLEN * 8) 226 return; 227 228 catsetp[(cat - 1) / 8] |= 0x80 >> ((cat - 1) % 8); 229} 230 231/* 232 * Present a pointer to the smack label in an inode blob. 233 */ 234static inline char *smk_of_inode(const struct inode *isp) 235{ 236 struct inode_smack *sip = isp->i_security; 237 return sip->smk_inode; 238} 239 240#endif /* _SECURITY_SMACK_H */ 241