diff options
Diffstat (limited to 'security/smack/smack.h')
| -rw-r--r-- | security/smack/smack.h | 386 |
1 files changed, 299 insertions, 87 deletions
diff --git a/security/smack/smack.h b/security/smack/smack.h index 62c1e982849..020307ef097 100644 --- a/security/smack/smack.h +++ b/security/smack/smack.h @@ -15,16 +15,60 @@ #include <linux/capability.h> #include <linux/spinlock.h> +#include <linux/security.h> +#include <linux/in.h> #include <net/netlabel.h> +#include <linux/list.h> +#include <linux/rculist.h> +#include <linux/lsm_audit.h> /* + * Smack labels were limited to 23 characters for a long time. + */ +#define SMK_LABELLEN 24 +#define SMK_LONGLABEL 256 + +/* + * 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. + * + * The cipso value associated with the label gets stored here, too. + * + * Keep the access rules for this subject label here so that + * the entire set of rules does not need to be examined every + * time. + */ +struct smack_known { + struct list_head list; + struct hlist_node smk_hashed; + char *smk_known; + u32 smk_secid; + struct netlbl_lsm_secattr smk_netlabel; /* on wire labels */ + struct list_head smk_rules; /* access rules */ + struct mutex smk_rules_lock; /* lock for rules */ +}; + +/* + * Maximum number of bytes for the levels in a CIPSO IP option. * 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) +#define SMK_CIPSOLEN 24 struct superblock_smack { char *smk_root; @@ -32,79 +76,65 @@ struct superblock_smack { 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 */ + struct smack_known *smk_out; /* outbound label */ + struct smack_known *smk_in; /* inbound label */ + struct smack_known *smk_packet; /* 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 */ + char *smk_inode; /* label of the fso */ + struct smack_known *smk_task; /* label of the task */ + struct smack_known *smk_mmap; /* label of the mmap domain */ + struct mutex smk_lock; /* initialization lock */ + int smk_flags; /* smack inode flags */ +}; + +struct task_smack { + struct smack_known *smk_task; /* label for access control */ + struct smack_known *smk_forked; /* label when forked */ + struct list_head smk_rules; /* per task access rules */ + struct mutex smk_rules_lock; /* lock for the rules */ }; #define SMK_INODE_INSTANT 0x01 /* inode is instantiated */ +#define SMK_INODE_TRANSMUTE 0x02 /* directory is transmuting */ +#define SMK_INODE_CHANGED 0x04 /* smack was transmuted */ /* * A label access rule. */ struct smack_rule { - char *smk_subject; - char *smk_object; - int smk_access; + struct list_head list; + struct smack_known *smk_subject; + char *smk_object; + int smk_access; }; /* - * An entry in the table of permitted label accesses. + * An entry in the table identifying hosts. */ -struct smk_list_entry { - struct smk_list_entry *smk_next; - struct smack_rule smk_rule; +struct smk_netlbladdr { + struct list_head list; + struct sockaddr_in smk_host; /* network address */ + struct in_addr smk_mask; /* network mask */ + char *smk_label; /* label */ }; /* - * An entry in the table mapping smack values to - * CIPSO level/category-set values. + * An entry in the table identifying ports. */ -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 */ +struct smk_port_label { + struct list_head list; + struct sock *smk_sock; /* socket initialized on */ + unsigned short smk_port; /* the port number */ + struct smack_known *smk_in; /* inbound label */ + struct smack_known *smk_out; /* outgoing label */ }; /* @@ -114,47 +144,86 @@ struct smack_known { #define SMK_FSFLOOR "smackfsfloor=" #define SMK_FSHAT "smackfshat=" #define SMK_FSROOT "smackfsroot=" +#define SMK_FSTRANS "smackfstransmute=" + +#define SMACK_CIPSO_OPTION "-CIPSO" /* - * xattr names + * How communications on this socket are treated. + * Usually it's determined by the underlying netlabel code + * but there are certain cases, including single label hosts + * and potentially single label interfaces for which the + * treatment can not be known in advance. + * + * The possibility of additional labeling schemes being + * introduced in the future exists as well. */ -#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 +#define SMACK_UNLABELED_SOCKET 0 +#define SMACK_CIPSO_SOCKET 1 /* - * smackfs macic number + * CIPSO defaults. */ -#define SMACK_MAGIC 0x43415d53 /* "SMAC" */ +#define SMACK_CIPSO_DOI_DEFAULT 3 /* Historical */ +#define SMACK_CIPSO_DOI_INVALID -1 /* Not a DOI */ +#define SMACK_CIPSO_DIRECT_DEFAULT 250 /* Arbitrary */ +#define SMACK_CIPSO_MAPPED_DEFAULT 251 /* Also arbitrary */ +#define SMACK_CIPSO_MAXLEVEL 255 /* CIPSO 2.2 standard */ +/* + * CIPSO 2.2 standard is 239, but Smack wants to use the + * categories in a structured way that limits the value to + * the bits in 23 bytes, hence the unusual number. + */ +#define SMACK_CIPSO_MAXCATNUM 184 /* 23 * 8 */ /* - * A limit on the number of entries in the lists - * makes some of the list administration easier. + * Ptrace rules */ -#define SMACK_LIST_MAX 10000 +#define SMACK_PTRACE_DEFAULT 0 +#define SMACK_PTRACE_EXACT 1 +#define SMACK_PTRACE_DRACONIAN 2 +#define SMACK_PTRACE_MAX SMACK_PTRACE_DRACONIAN /* - * CIPSO defaults. + * Flags for untraditional access modes. + * It shouldn't be necessary to avoid conflicts with definitions + * in fs.h, but do so anyway. */ -#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 */ +#define MAY_TRANSMUTE 0x00001000 /* Controls directory labeling */ +#define MAY_LOCK 0x00002000 /* Locks should be writes, but ... */ /* * 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 /* + * Number of access types used by Smack (rwxatl) + */ +#define SMK_NUM_ACCESS_TYPE 6 + +/* SMACK data */ +struct smack_audit_data { + const char *function; + char *subject; + char *object; + char *request; + int result; +}; + +/* + * Smack audit data; is empty if CONFIG_AUDIT not set + * to save some stack + */ +struct smk_audit_info { +#ifdef CONFIG_AUDIT + struct common_audit_data a; + struct smack_audit_data sad; +#endif +}; +/* * These functions are in smack_lsm.c */ struct inode_smack *new_inode_smack(char *); @@ -162,42 +231,53 @@ 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); +int smk_access_entry(char *, char *, struct list_head *); +int smk_access(struct smack_known *, char *, int, struct smk_audit_info *); +int smk_tskacc(struct task_smack *, char *, u32, struct smk_audit_info *); +int smk_curacc(char *, u32, struct smk_audit_info *); +struct smack_known *smack_from_secid(const u32); +char *smk_parse_smack(const char *string, int len); +int smk_netlbl_mls(int, char *, struct netlbl_lsm_secattr *, int); char *smk_import(const char *, int); struct smack_known *smk_import_entry(const char *, int); +void smk_insert_entry(struct smack_known *skp); +struct smack_known *smk_find_entry(const char *); u32 smack_to_secid(const char *); /* * Shared data. */ extern int smack_cipso_direct; -extern int smack_net_nltype; -extern char *smack_net_ambient; +extern int smack_cipso_mapped; +extern struct smack_known *smack_net_ambient; +extern struct smack_known *smack_onlycap; +extern struct smack_known *smack_syslog_label; +extern const char *smack_cipso_option; +extern int smack_ptrace_rule; -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 smack_known smack_known_web; + +extern struct mutex smack_known_lock; +extern struct list_head smack_known_list; +extern struct list_head smk_netlbladdr_list; + +extern struct security_operations smack_ops; -extern struct smk_list_entry *smack_list; +#define SMACK_HASH_SLOTS 16 +extern struct hlist_head smack_known_hash[SMACK_HASH_SLOTS]; /* - * Stricly for CIPSO level manipulation. - * Set the category bit number in a smack label sized buffer. + * Is the directory transmuting? */ -static inline void smack_catset_bit(int cat, char *catsetp) +static inline int smk_inode_transmutable(const struct inode *isp) { - if (cat > SMK_LABELLEN * 8) - return; - - catsetp[(cat - 1) / 8] |= 0x80 >> ((cat - 1) % 8); + struct inode_smack *sip = isp->i_security; + return (sip->smk_flags & SMK_INODE_TRANSMUTE) != 0; } /* @@ -209,4 +289,136 @@ static inline char *smk_of_inode(const struct inode *isp) return sip->smk_inode; } +/* + * Present a pointer to the smack label entry in an task blob. + */ +static inline struct smack_known *smk_of_task(const struct task_smack *tsp) +{ + return tsp->smk_task; +} + +/* + * Present a pointer to the forked smack label entry in an task blob. + */ +static inline struct smack_known *smk_of_forked(const struct task_smack *tsp) +{ + return tsp->smk_forked; +} + +/* + * Present a pointer to the smack label in the current task blob. + */ +static inline struct smack_known *smk_of_current(void) +{ + return smk_of_task(current_security()); +} + +/* + * Is the task privileged and allowed to be privileged + * by the onlycap rule. + */ +static inline int smack_privileged(int cap) +{ + struct smack_known *skp = smk_of_current(); + + if (!capable(cap)) + return 0; + if (smack_onlycap == NULL || smack_onlycap == skp) + return 1; + return 0; +} + +/* + * logging functions + */ +#define SMACK_AUDIT_DENIED 0x1 +#define SMACK_AUDIT_ACCEPT 0x2 +extern int log_policy; + +void smack_log(char *subject_label, char *object_label, + int request, + int result, struct smk_audit_info *auditdata); + +#ifdef CONFIG_AUDIT + +/* + * some inline functions to set up audit data + * they do nothing if CONFIG_AUDIT is not set + * + */ +static inline void smk_ad_init(struct smk_audit_info *a, const char *func, + char type) +{ + memset(&a->sad, 0, sizeof(a->sad)); + a->a.type = type; + a->a.smack_audit_data = &a->sad; + a->a.smack_audit_data->function = func; +} + +static inline void smk_ad_init_net(struct smk_audit_info *a, const char *func, + char type, struct lsm_network_audit *net) +{ + smk_ad_init(a, func, type); + memset(net, 0, sizeof(*net)); + a->a.u.net = net; +} + +static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a, + struct task_struct *t) +{ + a->a.u.tsk = t; +} +static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a, + struct dentry *d) +{ + a->a.u.dentry = d; +} +static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a, + struct inode *i) +{ + a->a.u.inode = i; +} +static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a, + struct path p) +{ + a->a.u.path = p; +} +static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a, + struct sock *sk) +{ + a->a.u.net->sk = sk; +} + +#else /* no AUDIT */ + +static inline void smk_ad_init(struct smk_audit_info *a, const char *func, + char type) +{ +} +static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a, + struct task_struct *t) +{ +} +static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a, + struct dentry *d) +{ +} +static inline void smk_ad_setfield_u_fs_path_mnt(struct smk_audit_info *a, + struct vfsmount *m) +{ +} +static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a, + struct inode *i) +{ +} +static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a, + struct path p) +{ +} +static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a, + struct sock *sk) +{ +} +#endif + #endif /* _SECURITY_SMACK_H */ |