/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * A policy database (policydb) specifies the
 * configuration data for the security policy.
 *
 * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
 */

/*
 * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
 *          Support for enhanced MLS infrastructure.
 *          Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
 *
 * Updated: Frank Mayer <mayerf@tresys.com> and
 *          Karl MacMillan <kmacmillan@tresys.com>
 *          Added conditional policy language extensions
 *          Copyright (C) 2003-2004 Tresys Technology, LLC
 */

#ifndef _SS_POLICYDB_H_
#define _SS_POLICYDB_H_

#include "symtab.h"
#include "avtab.h"
#include "sidtab.h"
#include "ebitmap.h"
#include "mls_types.h"
#include "context.h"
#include "constraint.h"

/*
 * A datum type is defined for each kind of symbol
 * in the configuration data:  individual permissions,
 * common prefixes for access vectors, classes,
 * users, roles, types, sensitivities, categories, etc.
 */

/* Permission attributes */
struct perm_datum {
        u32 value; /* permission bit + 1 */
};

/* Attributes of a common prefix for access vectors */
struct common_datum {
        u32 value; /* internal common value */
        struct symtab permissions; /* common permissions */
};

/* Class attributes */
struct class_datum {
        u32 value; /* class value */
        char *comkey; /* common name */
        struct common_datum *comdatum; /* common datum */
        struct symtab permissions; /* class-specific permission symbol table */
        struct constraint_node *constraints; /* constraints on class perms */
        struct constraint_node *validatetrans; /* special transition rules */
/* Options how a new object user, role, and type should be decided */
#define DEFAULT_SOURCE 1
#define DEFAULT_TARGET 2
        char default_user;
        char default_role;
        char default_type;
/* Options how a new object range should be decided */
#define DEFAULT_SOURCE_LOW      1
#define DEFAULT_SOURCE_HIGH     2
#define DEFAULT_SOURCE_LOW_HIGH 3
#define DEFAULT_TARGET_LOW      4
#define DEFAULT_TARGET_HIGH     5
#define DEFAULT_TARGET_LOW_HIGH 6
#define DEFAULT_GLBLUB          7
        char default_range;
};

/* Role attributes */
struct role_datum {
        u32 value; /* internal role value */
        u32 bounds; /* boundary of role */
        struct ebitmap dominates; /* set of roles dominated by this role */
        struct ebitmap types; /* set of authorized types for role */
};

struct role_trans_key {
        u32 role; /* current role */
        u32 type; /* program executable type, or new object type */
        u32 tclass; /* process class, or new object class */
};

struct role_trans_datum {
        u32 new_role; /* new role */
};

struct filename_trans_key {
        u32 ttype; /* parent dir context */
        u16 tclass; /* class of new object */
        const char *name; /* last path component */
};

struct filename_trans_datum {
        struct ebitmap stypes; /* bitmap of source types for this otype */
        u32 otype; /* resulting type of new object */
        struct filename_trans_datum *next; /* record for next otype*/
};

struct role_allow {
        u32 role; /* current role */
        u32 new_role; /* new role */
        struct role_allow *next;
};

/* Type attributes */
struct type_datum {
        u32 value; /* internal type value */
        u32 bounds; /* boundary of type */
        unsigned char primary; /* primary name? */
        unsigned char attribute; /* attribute ?*/
};

/* User attributes */
struct user_datum {
        u32 value; /* internal user value */
        u32 bounds; /* bounds of user */
        struct ebitmap roles; /* set of authorized roles for user */
        struct mls_range range; /* MLS range (min - max) for user */
        struct mls_level dfltlevel; /* default login MLS level for user */
};

/* Sensitivity attributes */
struct level_datum {
        struct mls_level level; /* sensitivity and associated categories */
        unsigned char isalias; /* is this sensitivity an alias for another? */
};

/* Category attributes */
struct cat_datum {
        u32 value; /* internal category bit + 1 */
        unsigned char isalias; /* is this category an alias for another? */
};

struct range_trans {
        u32 source_type;
        u32 target_type;
        u32 target_class;
};

/* Boolean data type */
struct cond_bool_datum {
        u32 value; /* internal type value */
        int state;
};

struct cond_node;

/*
 * type set preserves data needed to determine constraint info from
 * policy source. This is not used by the kernel policy but allows
 * utilities such as audit2allow to determine constraint denials.
 */
struct type_set {
        struct ebitmap types;
        struct ebitmap negset;
        u32 flags;
};

/*
 * The configuration data includes security contexts for
 * initial SIDs, unlabeled file systems, TCP and UDP port numbers,
 * network interfaces, and nodes.  This structure stores the
 * relevant data for one such entry.  Entries of the same kind
 * (e.g. all initial SIDs) are linked together into a list.
 */
struct ocontext {
        union {
                char *name; /* name of initial SID, fs, netif, fstype, path */
                struct {
                        u8 protocol;
                        u16 low_port;
                        u16 high_port;
                } port; /* TCP or UDP port information */
                struct {
                        u32 addr;
                        u32 mask;
                } node; /* node information */
                struct {
                        u32 addr[4];
                        u32 mask[4];
                } node6; /* IPv6 node information */
                struct {
                        u64 subnet_prefix;
                        u16 low_pkey;
                        u16 high_pkey;
                } ibpkey;
                struct {
                        char *dev_name;
                        u8 port;
                } ibendport;
        } u;
        union {
                u32 sclass; /* security class for genfs */
                u32 behavior; /* labeling behavior for fs_use */
        } v;
        struct context context[2]; /* security context(s) */
        u32 sid[2]; /* SID(s) */
        struct ocontext *next;
};

struct genfs {
        char *fstype;
        struct ocontext *head;
        struct genfs *next;
};

/* symbol table array indices */
#define SYM_COMMONS 0
#define SYM_CLASSES 1
#define SYM_ROLES   2
#define SYM_TYPES   3
#define SYM_USERS   4
#define SYM_BOOLS   5
#define SYM_LEVELS  6
#define SYM_CATS    7
#define SYM_NUM     8

/* object context array indices */
#define OCON_ISID      0 /* initial SIDs */
#define OCON_FS        1 /* unlabeled file systems (deprecated) */
#define OCON_PORT      2 /* TCP and UDP port numbers */
#define OCON_NETIF     3 /* network interfaces */
#define OCON_NODE      4 /* nodes */
#define OCON_FSUSE     5 /* fs_use */
#define OCON_NODE6     6 /* IPv6 nodes */
#define OCON_IBPKEY    7 /* Infiniband PKeys */
#define OCON_IBENDPORT 8 /* Infiniband end ports */
#define OCON_NUM       9

/* The policy database */
struct policydb {
        int mls_enabled;

        /* symbol tables */
        struct symtab symtab[SYM_NUM];
#define p_commons symtab[SYM_COMMONS]
#define p_classes symtab[SYM_CLASSES]
#define p_roles   symtab[SYM_ROLES]
#define p_types   symtab[SYM_TYPES]
#define p_users   symtab[SYM_USERS]
#define p_bools   symtab[SYM_BOOLS]
#define p_levels  symtab[SYM_LEVELS]
#define p_cats    symtab[SYM_CATS]

        /* symbol names indexed by (value - 1) */
        char **sym_val_to_name[SYM_NUM];

        /* class, role, and user attributes indexed by (value - 1) */
        struct class_datum **class_val_to_struct;
        struct role_datum **role_val_to_struct;
        struct user_datum **user_val_to_struct;
        struct type_datum **type_val_to_struct;

        /* type enforcement access vectors and transitions */
        struct avtab te_avtab;

        /* role transitions */
        struct hashtab role_tr;

        /* file transitions with the last path component */
        /* quickly exclude lookups when parent ttype has no rules */
        struct ebitmap filename_trans_ttypes;
        /* actual set of filename_trans rules */
        struct hashtab filename_trans;
        /* only used if policyvers < POLICYDB_VERSION_COMP_FTRANS */
        u32 compat_filename_trans_count;

        /* bools indexed by (value - 1) */
        struct cond_bool_datum **bool_val_to_struct;
        /* type enforcement conditional access vectors and transitions */
        struct avtab te_cond_avtab;
        /* array indexing te_cond_avtab by conditional */
        struct cond_node *cond_list;
        u32 cond_list_len;

        /* role allows */
        struct role_allow *role_allow;

        /* security contexts of initial SIDs, unlabeled file systems,
           TCP or UDP port numbers, network interfaces and nodes */
        struct ocontext *ocontexts[OCON_NUM];

        /* security contexts for files in filesystems that cannot support
           a persistent label mapping or use another
           fixed labeling behavior. */
        struct genfs *genfs;

        /* range transitions table (range_trans_key -> mls_range) */
        struct hashtab range_tr;

        /* type -> attribute reverse mapping */
        struct ebitmap *type_attr_map_array;

        struct ebitmap policycaps;

        struct ebitmap permissive_map;

        struct ebitmap neveraudit_map;

        /* length of this policy when it was loaded */
        size_t len;

        unsigned int policyvers;

        unsigned int reject_unknown : 1;
        unsigned int allow_unknown : 1;

        u16 process_class;
        u32 process_trans_perms;
} __randomize_layout;

struct policy_file {
        char *data;
        size_t len;
};

extern void policydb_destroy(struct policydb *p);
extern int policydb_load_isids(struct policydb *p, struct sidtab *s);
extern int policydb_context_isvalid(struct policydb *p, struct context *c);
extern int policydb_class_isvalid(struct policydb *p, unsigned int class);
extern int policydb_type_isvalid(struct policydb *p, unsigned int type);
extern int policydb_role_isvalid(struct policydb *p, unsigned int role);
extern int policydb_read(struct policydb *p, struct policy_file *fp);
extern int policydb_write(struct policydb *p, struct policy_file *fp);

extern struct filename_trans_datum *
policydb_filenametr_search(struct policydb *p, struct filename_trans_key *key);

extern struct mls_range *policydb_rangetr_search(struct policydb *p,
                                                 struct range_trans *key);

extern struct role_trans_datum *
policydb_roletr_search(struct policydb *p, struct role_trans_key *key);

#define POLICYDB_CONFIG_MLS 1

/* the config flags related to unknown classes/perms are bits 2 and 3 */
#define REJECT_UNKNOWN 0x00000002
#define ALLOW_UNKNOWN  0x00000004

#define OBJECT_R     "object_r"
#define OBJECT_R_VAL 1

#define POLICYDB_MAGIC  SELINUX_MAGIC
#define POLICYDB_STRING "SE Linux"

struct policy_data {
        struct policydb *p;
        struct policy_file *fp;
};

static inline int next_entry(void *buf, struct policy_file *fp, size_t bytes)
{
        if (bytes > fp->len)
                return -EINVAL;

        memcpy(buf, fp->data, bytes);
        fp->data += bytes;
        fp->len -= bytes;
        return 0;
}

static inline int put_entry(const void *buf, size_t bytes, size_t num,
                            struct policy_file *fp)
{
        size_t len;

        if (unlikely(check_mul_overflow(bytes, num, &len)))
                return -EINVAL;

        if (len > fp->len)
                return -EINVAL;
        memcpy(fp->data, buf, len);
        fp->data += len;
        fp->len -= len;

        return 0;
}

static inline char *sym_name(struct policydb *p, unsigned int sym_num,
                             unsigned int element_nr)
{
        return p->sym_val_to_name[sym_num][element_nr];
}

extern int str_read(char **strp, gfp_t flags, struct policy_file *fp, u32 len);

extern u16 string_to_security_class(struct policydb *p, const char *name);
extern u32 string_to_av_perm(struct policydb *p, u16 tclass, const char *name);

#endif /* _SS_POLICYDB_H_ */