linux_dsm_epyc7002/security/selinux/ss/policydb.h
Ondrej Mosnacek e0ac568de1 selinux: reduce the use of hard-coded hash sizes
Instead allocate hash tables with just the right size based on the
actual number of elements (which is almost always known beforehand, we
just need to defer the hashtab allocation to the right time). The only
case when we don't know the size (with the current policy format) is the
new filename transitions hashtable. Here I just left the existing value.

After this patch, the time to load Fedora policy on x86_64 decreases
from 790 ms to 167 ms. If the unconfined module is removed, it decreases
from 750 ms to 122 ms. It is also likely that other operations are going
to be faster, mainly string_to_context_struct() or mls_compute_sid(),
but I didn't try to quantify that.

The memory usage of all hash table arrays increases from ~58 KB to
~163 KB (with Fedora policy on x86_64).

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-27 19:23:20 -05:00

378 lines
10 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* A policy database (policydb) specifies the
* configuration data for the security policy.
*
* Author : Stephen Smalley, <sds@tycho.nsa.gov>
*/
/*
* Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
*
* Support for enhanced MLS infrastructure.
*
* Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
*
* Added conditional policy language extensions
*
* Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
* 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 permissions */
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 {
u32 role; /* current role */
u32 type; /* program executable type, or new object type */
u32 tclass; /* process class, or new object class */
u32 new_role; /* new role */
struct role_trans *next;
};
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 */
#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 role_trans *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;
u32 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;
/* 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;
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, void *fp);
extern int policydb_write(struct policydb *p, void *fp);
#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_file {
char *data;
size_t len;
};
struct policy_data {
struct policydb *p;
void *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, int num, struct policy_file *fp)
{
size_t len = bytes * num;
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 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_ */