1 files changed, 369 insertions, 0 deletions
diff --git a/security/smack/smack.h b/security/smack/smack.h
new file mode 100644
index 00000000..2b6c6a51
--- /dev/null
+++ b/security/smack/smack.h
@@ -0,0 +1,369 @@
+/*
+ * 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 <linux/security.h>
+#include <linux/in.h>
+#include <net/netlabel.h>
+#include <linux/list.h>
+#include <linux/rculist.h>
+#include <linux/lsm_audit.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)
+
+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 */
+	char		*smk_task;	/* label of the task */
+	char		*smk_mmap;	/* label of the mmap domain */
+	struct mutex	smk_lock;	/* initialization lock */
+	int		smk_flags;	/* smack inode flags */
+};
+
+struct task_smack {
+	char			*smk_task;	/* label for access control */
+	char			*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 */
+
+/*
+ * A label access rule.
+ */
+struct smack_rule {
+	struct list_head	list;
+	char			*smk_subject;
+	char			*smk_object;
+	int			smk_access;
+};
+
+/*
+ * 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];
+};
+
+/*
+ * An entry in the table identifying hosts.
+ */
+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 */
+};
+
+/*
+ * 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 list_head	list;
+	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="
+
+#define SMACK_CIPSO_OPTION 	"-CIPSO"
+
+/*
+ * 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 SMACK_UNLABELED_SOCKET	0
+#define SMACK_CIPSO_SOCKET	1
+
+/*
+ * smackfs magic number
+ * smackfs macic number
+ */
+#define SMACK_MAGIC	0x43415d53 /* "SMAC" */
+
+/*
+ * CIPSO defaults.
+ */
+#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_MAXCATVAL		63	/* Bigger gets harder */
+#define SMACK_CIPSO_MAXLEVEL            255     /* CIPSO 2.2 standard */
+#define SMACK_CIPSO_MAXCATNUM           239     /* CIPSO 2.2 standard */
+
+/*
+ * Flag for transmute access
+ */
+#define MAY_TRANSMUTE	64
+/*
+ * Just to make the common cases easier to deal with
+ */
+#define MAY_ANYREAD	(MAY_READ | MAY_EXEC)
+#define MAY_READWRITE	(MAY_READ | MAY_WRITE)
+#define MAY_NOT		0
+
+/*
+ * Number of access types used by Smack (rwxa)
+ */
+#define SMK_NUM_ACCESS_TYPE 4
+
+/*
+ * 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;
+#endif
+};
+/*
+ * These functions are in smack_lsm.c
+ */
+struct inode_smack *new_inode_smack(char *);
+
+/*
+ * These functions are in smack_access.c
+ */
+int smk_access_entry(char *, char *, struct list_head *);
+int smk_access(char *, char *, int, struct smk_audit_info *);
+int smk_curacc(char *, u32, struct smk_audit_info *);
+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 char *smack_net_ambient;
+extern char *smack_onlycap;
+extern const char *smack_cipso_option;
+
+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_web;
+
+extern struct list_head smack_known_list;
+extern struct list_head smack_rule_list;
+extern struct list_head smk_netlbladdr_list;
+
+extern struct security_operations smack_ops;
+
+/*
+ * 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);
+}
+
+/*
+ * Is the directory transmuting?
+ */
+static inline int smk_inode_transmutable(const struct inode *isp)
+{
+	struct inode_smack *sip = isp->i_security;
+	return (sip->smk_flags & SMK_INODE_TRANSMUTE) != 0;
+}
+
+/*
+ * 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;
+}
+
+/*
+ * Present a pointer to the smack label in an task blob.
+ */
+static inline char *smk_of_task(const struct task_smack *tsp)
+{
+	return tsp->smk_task;
+}
+
+/*
+ * Present a pointer to the forked smack label in an task blob.
+ */
+static inline char *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 char *smk_of_current(void)
+{
+	return smk_of_task(current_security());
+}
+
+/*
+ * 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, 0, sizeof(*a));
+	a->a.type = type;
+	a->a.smack_audit_data.function = func;
+}
+
+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 */