2690 lines
63 KiB
C
2690 lines
63 KiB
C
/*
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* Implementation of the security services.
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*
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* Authors : Stephen Smalley, <sds@epoch.ncsc.mil>
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* James Morris <jmorris@redhat.com>
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*
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* Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
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*
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* Support for enhanced MLS infrastructure.
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* Support for context based audit filters.
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*
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* Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
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*
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* Added conditional policy language extensions
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*
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* Updated: Hewlett-Packard <paul.moore@hp.com>
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*
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* Added support for NetLabel
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*
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* Copyright (C) 2006 Hewlett-Packard Development Company, L.P.
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* Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
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* Copyright (C) 2003 - 2004 Tresys Technology, LLC
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* Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, version 2.
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*/
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/string.h>
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#include <linux/spinlock.h>
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#include <linux/errno.h>
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#include <linux/in.h>
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#include <linux/sched.h>
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#include <linux/audit.h>
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#include <linux/mutex.h>
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#include <net/sock.h>
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#include <net/netlabel.h>
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#include "flask.h"
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#include "avc.h"
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#include "avc_ss.h"
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#include "security.h"
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#include "context.h"
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#include "policydb.h"
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#include "sidtab.h"
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#include "services.h"
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#include "conditional.h"
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#include "mls.h"
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#include "objsec.h"
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#include "selinux_netlabel.h"
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extern void selnl_notify_policyload(u32 seqno);
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unsigned int policydb_loaded_version;
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static DEFINE_RWLOCK(policy_rwlock);
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#define POLICY_RDLOCK read_lock(&policy_rwlock)
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#define POLICY_WRLOCK write_lock_irq(&policy_rwlock)
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#define POLICY_RDUNLOCK read_unlock(&policy_rwlock)
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#define POLICY_WRUNLOCK write_unlock_irq(&policy_rwlock)
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static DEFINE_MUTEX(load_mutex);
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#define LOAD_LOCK mutex_lock(&load_mutex)
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#define LOAD_UNLOCK mutex_unlock(&load_mutex)
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static struct sidtab sidtab;
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struct policydb policydb;
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int ss_initialized = 0;
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/*
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* The largest sequence number that has been used when
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* providing an access decision to the access vector cache.
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* The sequence number only changes when a policy change
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* occurs.
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*/
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static u32 latest_granting = 0;
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/* Forward declaration. */
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static int context_struct_to_string(struct context *context, char **scontext,
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u32 *scontext_len);
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/*
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* Return the boolean value of a constraint expression
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* when it is applied to the specified source and target
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* security contexts.
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*
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* xcontext is a special beast... It is used by the validatetrans rules
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* only. For these rules, scontext is the context before the transition,
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* tcontext is the context after the transition, and xcontext is the context
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* of the process performing the transition. All other callers of
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* constraint_expr_eval should pass in NULL for xcontext.
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*/
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static int constraint_expr_eval(struct context *scontext,
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struct context *tcontext,
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struct context *xcontext,
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struct constraint_expr *cexpr)
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{
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u32 val1, val2;
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struct context *c;
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struct role_datum *r1, *r2;
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struct mls_level *l1, *l2;
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struct constraint_expr *e;
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int s[CEXPR_MAXDEPTH];
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int sp = -1;
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for (e = cexpr; e; e = e->next) {
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switch (e->expr_type) {
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case CEXPR_NOT:
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BUG_ON(sp < 0);
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s[sp] = !s[sp];
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break;
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case CEXPR_AND:
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BUG_ON(sp < 1);
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sp--;
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s[sp] &= s[sp+1];
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break;
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case CEXPR_OR:
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BUG_ON(sp < 1);
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sp--;
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s[sp] |= s[sp+1];
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break;
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case CEXPR_ATTR:
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if (sp == (CEXPR_MAXDEPTH-1))
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return 0;
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switch (e->attr) {
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case CEXPR_USER:
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val1 = scontext->user;
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val2 = tcontext->user;
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break;
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case CEXPR_TYPE:
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val1 = scontext->type;
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val2 = tcontext->type;
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break;
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case CEXPR_ROLE:
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val1 = scontext->role;
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val2 = tcontext->role;
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r1 = policydb.role_val_to_struct[val1 - 1];
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r2 = policydb.role_val_to_struct[val2 - 1];
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switch (e->op) {
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case CEXPR_DOM:
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s[++sp] = ebitmap_get_bit(&r1->dominates,
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val2 - 1);
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continue;
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case CEXPR_DOMBY:
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s[++sp] = ebitmap_get_bit(&r2->dominates,
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val1 - 1);
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continue;
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case CEXPR_INCOMP:
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s[++sp] = ( !ebitmap_get_bit(&r1->dominates,
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val2 - 1) &&
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!ebitmap_get_bit(&r2->dominates,
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val1 - 1) );
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continue;
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default:
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break;
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}
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break;
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case CEXPR_L1L2:
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l1 = &(scontext->range.level[0]);
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l2 = &(tcontext->range.level[0]);
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goto mls_ops;
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case CEXPR_L1H2:
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l1 = &(scontext->range.level[0]);
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l2 = &(tcontext->range.level[1]);
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goto mls_ops;
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case CEXPR_H1L2:
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l1 = &(scontext->range.level[1]);
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l2 = &(tcontext->range.level[0]);
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goto mls_ops;
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case CEXPR_H1H2:
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l1 = &(scontext->range.level[1]);
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l2 = &(tcontext->range.level[1]);
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goto mls_ops;
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case CEXPR_L1H1:
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l1 = &(scontext->range.level[0]);
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l2 = &(scontext->range.level[1]);
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goto mls_ops;
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case CEXPR_L2H2:
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l1 = &(tcontext->range.level[0]);
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l2 = &(tcontext->range.level[1]);
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goto mls_ops;
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mls_ops:
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switch (e->op) {
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case CEXPR_EQ:
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s[++sp] = mls_level_eq(l1, l2);
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continue;
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case CEXPR_NEQ:
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s[++sp] = !mls_level_eq(l1, l2);
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continue;
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case CEXPR_DOM:
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s[++sp] = mls_level_dom(l1, l2);
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continue;
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case CEXPR_DOMBY:
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s[++sp] = mls_level_dom(l2, l1);
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continue;
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case CEXPR_INCOMP:
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s[++sp] = mls_level_incomp(l2, l1);
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continue;
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default:
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BUG();
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return 0;
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}
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break;
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default:
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BUG();
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return 0;
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}
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switch (e->op) {
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case CEXPR_EQ:
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s[++sp] = (val1 == val2);
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break;
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case CEXPR_NEQ:
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s[++sp] = (val1 != val2);
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break;
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default:
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BUG();
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return 0;
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}
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break;
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case CEXPR_NAMES:
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if (sp == (CEXPR_MAXDEPTH-1))
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return 0;
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c = scontext;
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if (e->attr & CEXPR_TARGET)
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c = tcontext;
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else if (e->attr & CEXPR_XTARGET) {
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c = xcontext;
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if (!c) {
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BUG();
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return 0;
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}
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}
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if (e->attr & CEXPR_USER)
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val1 = c->user;
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else if (e->attr & CEXPR_ROLE)
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val1 = c->role;
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else if (e->attr & CEXPR_TYPE)
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val1 = c->type;
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else {
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BUG();
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return 0;
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}
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switch (e->op) {
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case CEXPR_EQ:
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s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
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break;
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case CEXPR_NEQ:
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s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
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break;
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default:
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BUG();
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return 0;
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}
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break;
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default:
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BUG();
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return 0;
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}
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}
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BUG_ON(sp != 0);
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return s[0];
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}
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/*
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* Compute access vectors based on a context structure pair for
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* the permissions in a particular class.
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*/
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static int context_struct_compute_av(struct context *scontext,
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struct context *tcontext,
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u16 tclass,
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u32 requested,
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struct av_decision *avd)
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{
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struct constraint_node *constraint;
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struct role_allow *ra;
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struct avtab_key avkey;
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struct avtab_node *node;
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struct class_datum *tclass_datum;
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struct ebitmap *sattr, *tattr;
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struct ebitmap_node *snode, *tnode;
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unsigned int i, j;
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/*
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* Remap extended Netlink classes for old policy versions.
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* Do this here rather than socket_type_to_security_class()
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* in case a newer policy version is loaded, allowing sockets
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* to remain in the correct class.
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*/
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if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
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if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
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tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
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tclass = SECCLASS_NETLINK_SOCKET;
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if (!tclass || tclass > policydb.p_classes.nprim) {
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printk(KERN_ERR "security_compute_av: unrecognized class %d\n",
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tclass);
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return -EINVAL;
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}
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tclass_datum = policydb.class_val_to_struct[tclass - 1];
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|
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/*
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* Initialize the access vectors to the default values.
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*/
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avd->allowed = 0;
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avd->decided = 0xffffffff;
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avd->auditallow = 0;
|
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avd->auditdeny = 0xffffffff;
|
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avd->seqno = latest_granting;
|
|
|
|
/*
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* If a specific type enforcement rule was defined for
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* this permission check, then use it.
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*/
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avkey.target_class = tclass;
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avkey.specified = AVTAB_AV;
|
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sattr = &policydb.type_attr_map[scontext->type - 1];
|
|
tattr = &policydb.type_attr_map[tcontext->type - 1];
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ebitmap_for_each_bit(sattr, snode, i) {
|
|
if (!ebitmap_node_get_bit(snode, i))
|
|
continue;
|
|
ebitmap_for_each_bit(tattr, tnode, j) {
|
|
if (!ebitmap_node_get_bit(tnode, j))
|
|
continue;
|
|
avkey.source_type = i + 1;
|
|
avkey.target_type = j + 1;
|
|
for (node = avtab_search_node(&policydb.te_avtab, &avkey);
|
|
node != NULL;
|
|
node = avtab_search_node_next(node, avkey.specified)) {
|
|
if (node->key.specified == AVTAB_ALLOWED)
|
|
avd->allowed |= node->datum.data;
|
|
else if (node->key.specified == AVTAB_AUDITALLOW)
|
|
avd->auditallow |= node->datum.data;
|
|
else if (node->key.specified == AVTAB_AUDITDENY)
|
|
avd->auditdeny &= node->datum.data;
|
|
}
|
|
|
|
/* Check conditional av table for additional permissions */
|
|
cond_compute_av(&policydb.te_cond_avtab, &avkey, avd);
|
|
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Remove any permissions prohibited by a constraint (this includes
|
|
* the MLS policy).
|
|
*/
|
|
constraint = tclass_datum->constraints;
|
|
while (constraint) {
|
|
if ((constraint->permissions & (avd->allowed)) &&
|
|
!constraint_expr_eval(scontext, tcontext, NULL,
|
|
constraint->expr)) {
|
|
avd->allowed = (avd->allowed) & ~(constraint->permissions);
|
|
}
|
|
constraint = constraint->next;
|
|
}
|
|
|
|
/*
|
|
* If checking process transition permission and the
|
|
* role is changing, then check the (current_role, new_role)
|
|
* pair.
|
|
*/
|
|
if (tclass == SECCLASS_PROCESS &&
|
|
(avd->allowed & (PROCESS__TRANSITION | PROCESS__DYNTRANSITION)) &&
|
|
scontext->role != tcontext->role) {
|
|
for (ra = policydb.role_allow; ra; ra = ra->next) {
|
|
if (scontext->role == ra->role &&
|
|
tcontext->role == ra->new_role)
|
|
break;
|
|
}
|
|
if (!ra)
|
|
avd->allowed = (avd->allowed) & ~(PROCESS__TRANSITION |
|
|
PROCESS__DYNTRANSITION);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int security_validtrans_handle_fail(struct context *ocontext,
|
|
struct context *ncontext,
|
|
struct context *tcontext,
|
|
u16 tclass)
|
|
{
|
|
char *o = NULL, *n = NULL, *t = NULL;
|
|
u32 olen, nlen, tlen;
|
|
|
|
if (context_struct_to_string(ocontext, &o, &olen) < 0)
|
|
goto out;
|
|
if (context_struct_to_string(ncontext, &n, &nlen) < 0)
|
|
goto out;
|
|
if (context_struct_to_string(tcontext, &t, &tlen) < 0)
|
|
goto out;
|
|
audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
|
|
"security_validate_transition: denied for"
|
|
" oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
|
|
o, n, t, policydb.p_class_val_to_name[tclass-1]);
|
|
out:
|
|
kfree(o);
|
|
kfree(n);
|
|
kfree(t);
|
|
|
|
if (!selinux_enforcing)
|
|
return 0;
|
|
return -EPERM;
|
|
}
|
|
|
|
int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
|
|
u16 tclass)
|
|
{
|
|
struct context *ocontext;
|
|
struct context *ncontext;
|
|
struct context *tcontext;
|
|
struct class_datum *tclass_datum;
|
|
struct constraint_node *constraint;
|
|
int rc = 0;
|
|
|
|
if (!ss_initialized)
|
|
return 0;
|
|
|
|
POLICY_RDLOCK;
|
|
|
|
/*
|
|
* Remap extended Netlink classes for old policy versions.
|
|
* Do this here rather than socket_type_to_security_class()
|
|
* in case a newer policy version is loaded, allowing sockets
|
|
* to remain in the correct class.
|
|
*/
|
|
if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
|
|
if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
|
|
tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
|
|
tclass = SECCLASS_NETLINK_SOCKET;
|
|
|
|
if (!tclass || tclass > policydb.p_classes.nprim) {
|
|
printk(KERN_ERR "security_validate_transition: "
|
|
"unrecognized class %d\n", tclass);
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
tclass_datum = policydb.class_val_to_struct[tclass - 1];
|
|
|
|
ocontext = sidtab_search(&sidtab, oldsid);
|
|
if (!ocontext) {
|
|
printk(KERN_ERR "security_validate_transition: "
|
|
" unrecognized SID %d\n", oldsid);
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
ncontext = sidtab_search(&sidtab, newsid);
|
|
if (!ncontext) {
|
|
printk(KERN_ERR "security_validate_transition: "
|
|
" unrecognized SID %d\n", newsid);
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
tcontext = sidtab_search(&sidtab, tasksid);
|
|
if (!tcontext) {
|
|
printk(KERN_ERR "security_validate_transition: "
|
|
" unrecognized SID %d\n", tasksid);
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
constraint = tclass_datum->validatetrans;
|
|
while (constraint) {
|
|
if (!constraint_expr_eval(ocontext, ncontext, tcontext,
|
|
constraint->expr)) {
|
|
rc = security_validtrans_handle_fail(ocontext, ncontext,
|
|
tcontext, tclass);
|
|
goto out;
|
|
}
|
|
constraint = constraint->next;
|
|
}
|
|
|
|
out:
|
|
POLICY_RDUNLOCK;
|
|
return rc;
|
|
}
|
|
|
|
/**
|
|
* security_compute_av - Compute access vector decisions.
|
|
* @ssid: source security identifier
|
|
* @tsid: target security identifier
|
|
* @tclass: target security class
|
|
* @requested: requested permissions
|
|
* @avd: access vector decisions
|
|
*
|
|
* Compute a set of access vector decisions based on the
|
|
* SID pair (@ssid, @tsid) for the permissions in @tclass.
|
|
* Return -%EINVAL if any of the parameters are invalid or %0
|
|
* if the access vector decisions were computed successfully.
|
|
*/
|
|
int security_compute_av(u32 ssid,
|
|
u32 tsid,
|
|
u16 tclass,
|
|
u32 requested,
|
|
struct av_decision *avd)
|
|
{
|
|
struct context *scontext = NULL, *tcontext = NULL;
|
|
int rc = 0;
|
|
|
|
if (!ss_initialized) {
|
|
avd->allowed = 0xffffffff;
|
|
avd->decided = 0xffffffff;
|
|
avd->auditallow = 0;
|
|
avd->auditdeny = 0xffffffff;
|
|
avd->seqno = latest_granting;
|
|
return 0;
|
|
}
|
|
|
|
POLICY_RDLOCK;
|
|
|
|
scontext = sidtab_search(&sidtab, ssid);
|
|
if (!scontext) {
|
|
printk(KERN_ERR "security_compute_av: unrecognized SID %d\n",
|
|
ssid);
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
tcontext = sidtab_search(&sidtab, tsid);
|
|
if (!tcontext) {
|
|
printk(KERN_ERR "security_compute_av: unrecognized SID %d\n",
|
|
tsid);
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
rc = context_struct_compute_av(scontext, tcontext, tclass,
|
|
requested, avd);
|
|
out:
|
|
POLICY_RDUNLOCK;
|
|
return rc;
|
|
}
|
|
|
|
/*
|
|
* Write the security context string representation of
|
|
* the context structure `context' into a dynamically
|
|
* allocated string of the correct size. Set `*scontext'
|
|
* to point to this string and set `*scontext_len' to
|
|
* the length of the string.
|
|
*/
|
|
static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
|
|
{
|
|
char *scontextp;
|
|
|
|
*scontext = NULL;
|
|
*scontext_len = 0;
|
|
|
|
/* Compute the size of the context. */
|
|
*scontext_len += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1;
|
|
*scontext_len += strlen(policydb.p_role_val_to_name[context->role - 1]) + 1;
|
|
*scontext_len += strlen(policydb.p_type_val_to_name[context->type - 1]) + 1;
|
|
*scontext_len += mls_compute_context_len(context);
|
|
|
|
/* Allocate space for the context; caller must free this space. */
|
|
scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
|
|
if (!scontextp) {
|
|
return -ENOMEM;
|
|
}
|
|
*scontext = scontextp;
|
|
|
|
/*
|
|
* Copy the user name, role name and type name into the context.
|
|
*/
|
|
sprintf(scontextp, "%s:%s:%s",
|
|
policydb.p_user_val_to_name[context->user - 1],
|
|
policydb.p_role_val_to_name[context->role - 1],
|
|
policydb.p_type_val_to_name[context->type - 1]);
|
|
scontextp += strlen(policydb.p_user_val_to_name[context->user - 1]) +
|
|
1 + strlen(policydb.p_role_val_to_name[context->role - 1]) +
|
|
1 + strlen(policydb.p_type_val_to_name[context->type - 1]);
|
|
|
|
mls_sid_to_context(context, &scontextp);
|
|
|
|
*scontextp = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
#include "initial_sid_to_string.h"
|
|
|
|
/**
|
|
* security_sid_to_context - Obtain a context for a given SID.
|
|
* @sid: security identifier, SID
|
|
* @scontext: security context
|
|
* @scontext_len: length in bytes
|
|
*
|
|
* Write the string representation of the context associated with @sid
|
|
* into a dynamically allocated string of the correct size. Set @scontext
|
|
* to point to this string and set @scontext_len to the length of the string.
|
|
*/
|
|
int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
|
|
{
|
|
struct context *context;
|
|
int rc = 0;
|
|
|
|
if (!ss_initialized) {
|
|
if (sid <= SECINITSID_NUM) {
|
|
char *scontextp;
|
|
|
|
*scontext_len = strlen(initial_sid_to_string[sid]) + 1;
|
|
scontextp = kmalloc(*scontext_len,GFP_ATOMIC);
|
|
if (!scontextp) {
|
|
rc = -ENOMEM;
|
|
goto out;
|
|
}
|
|
strcpy(scontextp, initial_sid_to_string[sid]);
|
|
*scontext = scontextp;
|
|
goto out;
|
|
}
|
|
printk(KERN_ERR "security_sid_to_context: called before initial "
|
|
"load_policy on unknown SID %d\n", sid);
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
POLICY_RDLOCK;
|
|
context = sidtab_search(&sidtab, sid);
|
|
if (!context) {
|
|
printk(KERN_ERR "security_sid_to_context: unrecognized SID "
|
|
"%d\n", sid);
|
|
rc = -EINVAL;
|
|
goto out_unlock;
|
|
}
|
|
rc = context_struct_to_string(context, scontext, scontext_len);
|
|
out_unlock:
|
|
POLICY_RDUNLOCK;
|
|
out:
|
|
return rc;
|
|
|
|
}
|
|
|
|
static int security_context_to_sid_core(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid)
|
|
{
|
|
char *scontext2;
|
|
struct context context;
|
|
struct role_datum *role;
|
|
struct type_datum *typdatum;
|
|
struct user_datum *usrdatum;
|
|
char *scontextp, *p, oldc;
|
|
int rc = 0;
|
|
|
|
if (!ss_initialized) {
|
|
int i;
|
|
|
|
for (i = 1; i < SECINITSID_NUM; i++) {
|
|
if (!strcmp(initial_sid_to_string[i], scontext)) {
|
|
*sid = i;
|
|
goto out;
|
|
}
|
|
}
|
|
*sid = SECINITSID_KERNEL;
|
|
goto out;
|
|
}
|
|
*sid = SECSID_NULL;
|
|
|
|
/* Copy the string so that we can modify the copy as we parse it.
|
|
The string should already by null terminated, but we append a
|
|
null suffix to the copy to avoid problems with the existing
|
|
attr package, which doesn't view the null terminator as part
|
|
of the attribute value. */
|
|
scontext2 = kmalloc(scontext_len+1,GFP_KERNEL);
|
|
if (!scontext2) {
|
|
rc = -ENOMEM;
|
|
goto out;
|
|
}
|
|
memcpy(scontext2, scontext, scontext_len);
|
|
scontext2[scontext_len] = 0;
|
|
|
|
context_init(&context);
|
|
*sid = SECSID_NULL;
|
|
|
|
POLICY_RDLOCK;
|
|
|
|
/* Parse the security context. */
|
|
|
|
rc = -EINVAL;
|
|
scontextp = (char *) scontext2;
|
|
|
|
/* Extract the user. */
|
|
p = scontextp;
|
|
while (*p && *p != ':')
|
|
p++;
|
|
|
|
if (*p == 0)
|
|
goto out_unlock;
|
|
|
|
*p++ = 0;
|
|
|
|
usrdatum = hashtab_search(policydb.p_users.table, scontextp);
|
|
if (!usrdatum)
|
|
goto out_unlock;
|
|
|
|
context.user = usrdatum->value;
|
|
|
|
/* Extract role. */
|
|
scontextp = p;
|
|
while (*p && *p != ':')
|
|
p++;
|
|
|
|
if (*p == 0)
|
|
goto out_unlock;
|
|
|
|
*p++ = 0;
|
|
|
|
role = hashtab_search(policydb.p_roles.table, scontextp);
|
|
if (!role)
|
|
goto out_unlock;
|
|
context.role = role->value;
|
|
|
|
/* Extract type. */
|
|
scontextp = p;
|
|
while (*p && *p != ':')
|
|
p++;
|
|
oldc = *p;
|
|
*p++ = 0;
|
|
|
|
typdatum = hashtab_search(policydb.p_types.table, scontextp);
|
|
if (!typdatum)
|
|
goto out_unlock;
|
|
|
|
context.type = typdatum->value;
|
|
|
|
rc = mls_context_to_sid(oldc, &p, &context, &sidtab, def_sid);
|
|
if (rc)
|
|
goto out_unlock;
|
|
|
|
if ((p - scontext2) < scontext_len) {
|
|
rc = -EINVAL;
|
|
goto out_unlock;
|
|
}
|
|
|
|
/* Check the validity of the new context. */
|
|
if (!policydb_context_isvalid(&policydb, &context)) {
|
|
rc = -EINVAL;
|
|
goto out_unlock;
|
|
}
|
|
/* Obtain the new sid. */
|
|
rc = sidtab_context_to_sid(&sidtab, &context, sid);
|
|
out_unlock:
|
|
POLICY_RDUNLOCK;
|
|
context_destroy(&context);
|
|
kfree(scontext2);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
/**
|
|
* security_context_to_sid - Obtain a SID for a given security context.
|
|
* @scontext: security context
|
|
* @scontext_len: length in bytes
|
|
* @sid: security identifier, SID
|
|
*
|
|
* Obtains a SID associated with the security context that
|
|
* has the string representation specified by @scontext.
|
|
* Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
|
|
* memory is available, or 0 on success.
|
|
*/
|
|
int security_context_to_sid(char *scontext, u32 scontext_len, u32 *sid)
|
|
{
|
|
return security_context_to_sid_core(scontext, scontext_len,
|
|
sid, SECSID_NULL);
|
|
}
|
|
|
|
/**
|
|
* security_context_to_sid_default - Obtain a SID for a given security context,
|
|
* falling back to specified default if needed.
|
|
*
|
|
* @scontext: security context
|
|
* @scontext_len: length in bytes
|
|
* @sid: security identifier, SID
|
|
* @def_sid: default SID to assign on errror
|
|
*
|
|
* Obtains a SID associated with the security context that
|
|
* has the string representation specified by @scontext.
|
|
* The default SID is passed to the MLS layer to be used to allow
|
|
* kernel labeling of the MLS field if the MLS field is not present
|
|
* (for upgrading to MLS without full relabel).
|
|
* Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
|
|
* memory is available, or 0 on success.
|
|
*/
|
|
int security_context_to_sid_default(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid)
|
|
{
|
|
return security_context_to_sid_core(scontext, scontext_len,
|
|
sid, def_sid);
|
|
}
|
|
|
|
static int compute_sid_handle_invalid_context(
|
|
struct context *scontext,
|
|
struct context *tcontext,
|
|
u16 tclass,
|
|
struct context *newcontext)
|
|
{
|
|
char *s = NULL, *t = NULL, *n = NULL;
|
|
u32 slen, tlen, nlen;
|
|
|
|
if (context_struct_to_string(scontext, &s, &slen) < 0)
|
|
goto out;
|
|
if (context_struct_to_string(tcontext, &t, &tlen) < 0)
|
|
goto out;
|
|
if (context_struct_to_string(newcontext, &n, &nlen) < 0)
|
|
goto out;
|
|
audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
|
|
"security_compute_sid: invalid context %s"
|
|
" for scontext=%s"
|
|
" tcontext=%s"
|
|
" tclass=%s",
|
|
n, s, t, policydb.p_class_val_to_name[tclass-1]);
|
|
out:
|
|
kfree(s);
|
|
kfree(t);
|
|
kfree(n);
|
|
if (!selinux_enforcing)
|
|
return 0;
|
|
return -EACCES;
|
|
}
|
|
|
|
static int security_compute_sid(u32 ssid,
|
|
u32 tsid,
|
|
u16 tclass,
|
|
u32 specified,
|
|
u32 *out_sid)
|
|
{
|
|
struct context *scontext = NULL, *tcontext = NULL, newcontext;
|
|
struct role_trans *roletr = NULL;
|
|
struct avtab_key avkey;
|
|
struct avtab_datum *avdatum;
|
|
struct avtab_node *node;
|
|
int rc = 0;
|
|
|
|
if (!ss_initialized) {
|
|
switch (tclass) {
|
|
case SECCLASS_PROCESS:
|
|
*out_sid = ssid;
|
|
break;
|
|
default:
|
|
*out_sid = tsid;
|
|
break;
|
|
}
|
|
goto out;
|
|
}
|
|
|
|
context_init(&newcontext);
|
|
|
|
POLICY_RDLOCK;
|
|
|
|
scontext = sidtab_search(&sidtab, ssid);
|
|
if (!scontext) {
|
|
printk(KERN_ERR "security_compute_sid: unrecognized SID %d\n",
|
|
ssid);
|
|
rc = -EINVAL;
|
|
goto out_unlock;
|
|
}
|
|
tcontext = sidtab_search(&sidtab, tsid);
|
|
if (!tcontext) {
|
|
printk(KERN_ERR "security_compute_sid: unrecognized SID %d\n",
|
|
tsid);
|
|
rc = -EINVAL;
|
|
goto out_unlock;
|
|
}
|
|
|
|
/* Set the user identity. */
|
|
switch (specified) {
|
|
case AVTAB_TRANSITION:
|
|
case AVTAB_CHANGE:
|
|
/* Use the process user identity. */
|
|
newcontext.user = scontext->user;
|
|
break;
|
|
case AVTAB_MEMBER:
|
|
/* Use the related object owner. */
|
|
newcontext.user = tcontext->user;
|
|
break;
|
|
}
|
|
|
|
/* Set the role and type to default values. */
|
|
switch (tclass) {
|
|
case SECCLASS_PROCESS:
|
|
/* Use the current role and type of process. */
|
|
newcontext.role = scontext->role;
|
|
newcontext.type = scontext->type;
|
|
break;
|
|
default:
|
|
/* Use the well-defined object role. */
|
|
newcontext.role = OBJECT_R_VAL;
|
|
/* Use the type of the related object. */
|
|
newcontext.type = tcontext->type;
|
|
}
|
|
|
|
/* Look for a type transition/member/change rule. */
|
|
avkey.source_type = scontext->type;
|
|
avkey.target_type = tcontext->type;
|
|
avkey.target_class = tclass;
|
|
avkey.specified = specified;
|
|
avdatum = avtab_search(&policydb.te_avtab, &avkey);
|
|
|
|
/* If no permanent rule, also check for enabled conditional rules */
|
|
if(!avdatum) {
|
|
node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
|
|
for (; node != NULL; node = avtab_search_node_next(node, specified)) {
|
|
if (node->key.specified & AVTAB_ENABLED) {
|
|
avdatum = &node->datum;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (avdatum) {
|
|
/* Use the type from the type transition/member/change rule. */
|
|
newcontext.type = avdatum->data;
|
|
}
|
|
|
|
/* Check for class-specific changes. */
|
|
switch (tclass) {
|
|
case SECCLASS_PROCESS:
|
|
if (specified & AVTAB_TRANSITION) {
|
|
/* Look for a role transition rule. */
|
|
for (roletr = policydb.role_tr; roletr;
|
|
roletr = roletr->next) {
|
|
if (roletr->role == scontext->role &&
|
|
roletr->type == tcontext->type) {
|
|
/* Use the role transition rule. */
|
|
newcontext.role = roletr->new_role;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
/* Set the MLS attributes.
|
|
This is done last because it may allocate memory. */
|
|
rc = mls_compute_sid(scontext, tcontext, tclass, specified, &newcontext);
|
|
if (rc)
|
|
goto out_unlock;
|
|
|
|
/* Check the validity of the context. */
|
|
if (!policydb_context_isvalid(&policydb, &newcontext)) {
|
|
rc = compute_sid_handle_invalid_context(scontext,
|
|
tcontext,
|
|
tclass,
|
|
&newcontext);
|
|
if (rc)
|
|
goto out_unlock;
|
|
}
|
|
/* Obtain the sid for the context. */
|
|
rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
|
|
out_unlock:
|
|
POLICY_RDUNLOCK;
|
|
context_destroy(&newcontext);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
/**
|
|
* security_transition_sid - Compute the SID for a new subject/object.
|
|
* @ssid: source security identifier
|
|
* @tsid: target security identifier
|
|
* @tclass: target security class
|
|
* @out_sid: security identifier for new subject/object
|
|
*
|
|
* Compute a SID to use for labeling a new subject or object in the
|
|
* class @tclass based on a SID pair (@ssid, @tsid).
|
|
* Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
|
|
* if insufficient memory is available, or %0 if the new SID was
|
|
* computed successfully.
|
|
*/
|
|
int security_transition_sid(u32 ssid,
|
|
u32 tsid,
|
|
u16 tclass,
|
|
u32 *out_sid)
|
|
{
|
|
return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, out_sid);
|
|
}
|
|
|
|
/**
|
|
* security_member_sid - Compute the SID for member selection.
|
|
* @ssid: source security identifier
|
|
* @tsid: target security identifier
|
|
* @tclass: target security class
|
|
* @out_sid: security identifier for selected member
|
|
*
|
|
* Compute a SID to use when selecting a member of a polyinstantiated
|
|
* object of class @tclass based on a SID pair (@ssid, @tsid).
|
|
* Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
|
|
* if insufficient memory is available, or %0 if the SID was
|
|
* computed successfully.
|
|
*/
|
|
int security_member_sid(u32 ssid,
|
|
u32 tsid,
|
|
u16 tclass,
|
|
u32 *out_sid)
|
|
{
|
|
return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, out_sid);
|
|
}
|
|
|
|
/**
|
|
* security_change_sid - Compute the SID for object relabeling.
|
|
* @ssid: source security identifier
|
|
* @tsid: target security identifier
|
|
* @tclass: target security class
|
|
* @out_sid: security identifier for selected member
|
|
*
|
|
* Compute a SID to use for relabeling an object of class @tclass
|
|
* based on a SID pair (@ssid, @tsid).
|
|
* Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
|
|
* if insufficient memory is available, or %0 if the SID was
|
|
* computed successfully.
|
|
*/
|
|
int security_change_sid(u32 ssid,
|
|
u32 tsid,
|
|
u16 tclass,
|
|
u32 *out_sid)
|
|
{
|
|
return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, out_sid);
|
|
}
|
|
|
|
/*
|
|
* Verify that each permission that is defined under the
|
|
* existing policy is still defined with the same value
|
|
* in the new policy.
|
|
*/
|
|
static int validate_perm(void *key, void *datum, void *p)
|
|
{
|
|
struct hashtab *h;
|
|
struct perm_datum *perdatum, *perdatum2;
|
|
int rc = 0;
|
|
|
|
|
|
h = p;
|
|
perdatum = datum;
|
|
|
|
perdatum2 = hashtab_search(h, key);
|
|
if (!perdatum2) {
|
|
printk(KERN_ERR "security: permission %s disappeared",
|
|
(char *)key);
|
|
rc = -ENOENT;
|
|
goto out;
|
|
}
|
|
if (perdatum->value != perdatum2->value) {
|
|
printk(KERN_ERR "security: the value of permission %s changed",
|
|
(char *)key);
|
|
rc = -EINVAL;
|
|
}
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
/*
|
|
* Verify that each class that is defined under the
|
|
* existing policy is still defined with the same
|
|
* attributes in the new policy.
|
|
*/
|
|
static int validate_class(void *key, void *datum, void *p)
|
|
{
|
|
struct policydb *newp;
|
|
struct class_datum *cladatum, *cladatum2;
|
|
int rc;
|
|
|
|
newp = p;
|
|
cladatum = datum;
|
|
|
|
cladatum2 = hashtab_search(newp->p_classes.table, key);
|
|
if (!cladatum2) {
|
|
printk(KERN_ERR "security: class %s disappeared\n",
|
|
(char *)key);
|
|
rc = -ENOENT;
|
|
goto out;
|
|
}
|
|
if (cladatum->value != cladatum2->value) {
|
|
printk(KERN_ERR "security: the value of class %s changed\n",
|
|
(char *)key);
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
if ((cladatum->comdatum && !cladatum2->comdatum) ||
|
|
(!cladatum->comdatum && cladatum2->comdatum)) {
|
|
printk(KERN_ERR "security: the inherits clause for the access "
|
|
"vector definition for class %s changed\n", (char *)key);
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
if (cladatum->comdatum) {
|
|
rc = hashtab_map(cladatum->comdatum->permissions.table, validate_perm,
|
|
cladatum2->comdatum->permissions.table);
|
|
if (rc) {
|
|
printk(" in the access vector definition for class "
|
|
"%s\n", (char *)key);
|
|
goto out;
|
|
}
|
|
}
|
|
rc = hashtab_map(cladatum->permissions.table, validate_perm,
|
|
cladatum2->permissions.table);
|
|
if (rc)
|
|
printk(" in access vector definition for class %s\n",
|
|
(char *)key);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
/* Clone the SID into the new SID table. */
|
|
static int clone_sid(u32 sid,
|
|
struct context *context,
|
|
void *arg)
|
|
{
|
|
struct sidtab *s = arg;
|
|
|
|
return sidtab_insert(s, sid, context);
|
|
}
|
|
|
|
static inline int convert_context_handle_invalid_context(struct context *context)
|
|
{
|
|
int rc = 0;
|
|
|
|
if (selinux_enforcing) {
|
|
rc = -EINVAL;
|
|
} else {
|
|
char *s;
|
|
u32 len;
|
|
|
|
context_struct_to_string(context, &s, &len);
|
|
printk(KERN_ERR "security: context %s is invalid\n", s);
|
|
kfree(s);
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
struct convert_context_args {
|
|
struct policydb *oldp;
|
|
struct policydb *newp;
|
|
};
|
|
|
|
/*
|
|
* Convert the values in the security context
|
|
* structure `c' from the values specified
|
|
* in the policy `p->oldp' to the values specified
|
|
* in the policy `p->newp'. Verify that the
|
|
* context is valid under the new policy.
|
|
*/
|
|
static int convert_context(u32 key,
|
|
struct context *c,
|
|
void *p)
|
|
{
|
|
struct convert_context_args *args;
|
|
struct context oldc;
|
|
struct role_datum *role;
|
|
struct type_datum *typdatum;
|
|
struct user_datum *usrdatum;
|
|
char *s;
|
|
u32 len;
|
|
int rc;
|
|
|
|
args = p;
|
|
|
|
rc = context_cpy(&oldc, c);
|
|
if (rc)
|
|
goto out;
|
|
|
|
rc = -EINVAL;
|
|
|
|
/* Convert the user. */
|
|
usrdatum = hashtab_search(args->newp->p_users.table,
|
|
args->oldp->p_user_val_to_name[c->user - 1]);
|
|
if (!usrdatum) {
|
|
goto bad;
|
|
}
|
|
c->user = usrdatum->value;
|
|
|
|
/* Convert the role. */
|
|
role = hashtab_search(args->newp->p_roles.table,
|
|
args->oldp->p_role_val_to_name[c->role - 1]);
|
|
if (!role) {
|
|
goto bad;
|
|
}
|
|
c->role = role->value;
|
|
|
|
/* Convert the type. */
|
|
typdatum = hashtab_search(args->newp->p_types.table,
|
|
args->oldp->p_type_val_to_name[c->type - 1]);
|
|
if (!typdatum) {
|
|
goto bad;
|
|
}
|
|
c->type = typdatum->value;
|
|
|
|
rc = mls_convert_context(args->oldp, args->newp, c);
|
|
if (rc)
|
|
goto bad;
|
|
|
|
/* Check the validity of the new context. */
|
|
if (!policydb_context_isvalid(args->newp, c)) {
|
|
rc = convert_context_handle_invalid_context(&oldc);
|
|
if (rc)
|
|
goto bad;
|
|
}
|
|
|
|
context_destroy(&oldc);
|
|
out:
|
|
return rc;
|
|
bad:
|
|
context_struct_to_string(&oldc, &s, &len);
|
|
context_destroy(&oldc);
|
|
printk(KERN_ERR "security: invalidating context %s\n", s);
|
|
kfree(s);
|
|
goto out;
|
|
}
|
|
|
|
extern void selinux_complete_init(void);
|
|
|
|
/**
|
|
* security_load_policy - Load a security policy configuration.
|
|
* @data: binary policy data
|
|
* @len: length of data in bytes
|
|
*
|
|
* Load a new set of security policy configuration data,
|
|
* validate it and convert the SID table as necessary.
|
|
* This function will flush the access vector cache after
|
|
* loading the new policy.
|
|
*/
|
|
int security_load_policy(void *data, size_t len)
|
|
{
|
|
struct policydb oldpolicydb, newpolicydb;
|
|
struct sidtab oldsidtab, newsidtab;
|
|
struct convert_context_args args;
|
|
u32 seqno;
|
|
int rc = 0;
|
|
struct policy_file file = { data, len }, *fp = &file;
|
|
|
|
LOAD_LOCK;
|
|
|
|
if (!ss_initialized) {
|
|
avtab_cache_init();
|
|
if (policydb_read(&policydb, fp)) {
|
|
LOAD_UNLOCK;
|
|
avtab_cache_destroy();
|
|
return -EINVAL;
|
|
}
|
|
if (policydb_load_isids(&policydb, &sidtab)) {
|
|
LOAD_UNLOCK;
|
|
policydb_destroy(&policydb);
|
|
avtab_cache_destroy();
|
|
return -EINVAL;
|
|
}
|
|
policydb_loaded_version = policydb.policyvers;
|
|
ss_initialized = 1;
|
|
seqno = ++latest_granting;
|
|
LOAD_UNLOCK;
|
|
selinux_complete_init();
|
|
avc_ss_reset(seqno);
|
|
selnl_notify_policyload(seqno);
|
|
selinux_netlbl_cache_invalidate();
|
|
return 0;
|
|
}
|
|
|
|
#if 0
|
|
sidtab_hash_eval(&sidtab, "sids");
|
|
#endif
|
|
|
|
if (policydb_read(&newpolicydb, fp)) {
|
|
LOAD_UNLOCK;
|
|
return -EINVAL;
|
|
}
|
|
|
|
sidtab_init(&newsidtab);
|
|
|
|
/* Verify that the existing classes did not change. */
|
|
if (hashtab_map(policydb.p_classes.table, validate_class, &newpolicydb)) {
|
|
printk(KERN_ERR "security: the definition of an existing "
|
|
"class changed\n");
|
|
rc = -EINVAL;
|
|
goto err;
|
|
}
|
|
|
|
/* Clone the SID table. */
|
|
sidtab_shutdown(&sidtab);
|
|
if (sidtab_map(&sidtab, clone_sid, &newsidtab)) {
|
|
rc = -ENOMEM;
|
|
goto err;
|
|
}
|
|
|
|
/* Convert the internal representations of contexts
|
|
in the new SID table and remove invalid SIDs. */
|
|
args.oldp = &policydb;
|
|
args.newp = &newpolicydb;
|
|
sidtab_map_remove_on_error(&newsidtab, convert_context, &args);
|
|
|
|
/* Save the old policydb and SID table to free later. */
|
|
memcpy(&oldpolicydb, &policydb, sizeof policydb);
|
|
sidtab_set(&oldsidtab, &sidtab);
|
|
|
|
/* Install the new policydb and SID table. */
|
|
POLICY_WRLOCK;
|
|
memcpy(&policydb, &newpolicydb, sizeof policydb);
|
|
sidtab_set(&sidtab, &newsidtab);
|
|
seqno = ++latest_granting;
|
|
policydb_loaded_version = policydb.policyvers;
|
|
POLICY_WRUNLOCK;
|
|
LOAD_UNLOCK;
|
|
|
|
/* Free the old policydb and SID table. */
|
|
policydb_destroy(&oldpolicydb);
|
|
sidtab_destroy(&oldsidtab);
|
|
|
|
avc_ss_reset(seqno);
|
|
selnl_notify_policyload(seqno);
|
|
selinux_netlbl_cache_invalidate();
|
|
|
|
return 0;
|
|
|
|
err:
|
|
LOAD_UNLOCK;
|
|
sidtab_destroy(&newsidtab);
|
|
policydb_destroy(&newpolicydb);
|
|
return rc;
|
|
|
|
}
|
|
|
|
/**
|
|
* security_port_sid - Obtain the SID for a port.
|
|
* @domain: communication domain aka address family
|
|
* @type: socket type
|
|
* @protocol: protocol number
|
|
* @port: port number
|
|
* @out_sid: security identifier
|
|
*/
|
|
int security_port_sid(u16 domain,
|
|
u16 type,
|
|
u8 protocol,
|
|
u16 port,
|
|
u32 *out_sid)
|
|
{
|
|
struct ocontext *c;
|
|
int rc = 0;
|
|
|
|
POLICY_RDLOCK;
|
|
|
|
c = policydb.ocontexts[OCON_PORT];
|
|
while (c) {
|
|
if (c->u.port.protocol == protocol &&
|
|
c->u.port.low_port <= port &&
|
|
c->u.port.high_port >= port)
|
|
break;
|
|
c = c->next;
|
|
}
|
|
|
|
if (c) {
|
|
if (!c->sid[0]) {
|
|
rc = sidtab_context_to_sid(&sidtab,
|
|
&c->context[0],
|
|
&c->sid[0]);
|
|
if (rc)
|
|
goto out;
|
|
}
|
|
*out_sid = c->sid[0];
|
|
} else {
|
|
*out_sid = SECINITSID_PORT;
|
|
}
|
|
|
|
out:
|
|
POLICY_RDUNLOCK;
|
|
return rc;
|
|
}
|
|
|
|
/**
|
|
* security_netif_sid - Obtain the SID for a network interface.
|
|
* @name: interface name
|
|
* @if_sid: interface SID
|
|
* @msg_sid: default SID for received packets
|
|
*/
|
|
int security_netif_sid(char *name,
|
|
u32 *if_sid,
|
|
u32 *msg_sid)
|
|
{
|
|
int rc = 0;
|
|
struct ocontext *c;
|
|
|
|
POLICY_RDLOCK;
|
|
|
|
c = policydb.ocontexts[OCON_NETIF];
|
|
while (c) {
|
|
if (strcmp(name, c->u.name) == 0)
|
|
break;
|
|
c = c->next;
|
|
}
|
|
|
|
if (c) {
|
|
if (!c->sid[0] || !c->sid[1]) {
|
|
rc = sidtab_context_to_sid(&sidtab,
|
|
&c->context[0],
|
|
&c->sid[0]);
|
|
if (rc)
|
|
goto out;
|
|
rc = sidtab_context_to_sid(&sidtab,
|
|
&c->context[1],
|
|
&c->sid[1]);
|
|
if (rc)
|
|
goto out;
|
|
}
|
|
*if_sid = c->sid[0];
|
|
*msg_sid = c->sid[1];
|
|
} else {
|
|
*if_sid = SECINITSID_NETIF;
|
|
*msg_sid = SECINITSID_NETMSG;
|
|
}
|
|
|
|
out:
|
|
POLICY_RDUNLOCK;
|
|
return rc;
|
|
}
|
|
|
|
static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
|
|
{
|
|
int i, fail = 0;
|
|
|
|
for(i = 0; i < 4; i++)
|
|
if(addr[i] != (input[i] & mask[i])) {
|
|
fail = 1;
|
|
break;
|
|
}
|
|
|
|
return !fail;
|
|
}
|
|
|
|
/**
|
|
* security_node_sid - Obtain the SID for a node (host).
|
|
* @domain: communication domain aka address family
|
|
* @addrp: address
|
|
* @addrlen: address length in bytes
|
|
* @out_sid: security identifier
|
|
*/
|
|
int security_node_sid(u16 domain,
|
|
void *addrp,
|
|
u32 addrlen,
|
|
u32 *out_sid)
|
|
{
|
|
int rc = 0;
|
|
struct ocontext *c;
|
|
|
|
POLICY_RDLOCK;
|
|
|
|
switch (domain) {
|
|
case AF_INET: {
|
|
u32 addr;
|
|
|
|
if (addrlen != sizeof(u32)) {
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
addr = *((u32 *)addrp);
|
|
|
|
c = policydb.ocontexts[OCON_NODE];
|
|
while (c) {
|
|
if (c->u.node.addr == (addr & c->u.node.mask))
|
|
break;
|
|
c = c->next;
|
|
}
|
|
break;
|
|
}
|
|
|
|
case AF_INET6:
|
|
if (addrlen != sizeof(u64) * 2) {
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
c = policydb.ocontexts[OCON_NODE6];
|
|
while (c) {
|
|
if (match_ipv6_addrmask(addrp, c->u.node6.addr,
|
|
c->u.node6.mask))
|
|
break;
|
|
c = c->next;
|
|
}
|
|
break;
|
|
|
|
default:
|
|
*out_sid = SECINITSID_NODE;
|
|
goto out;
|
|
}
|
|
|
|
if (c) {
|
|
if (!c->sid[0]) {
|
|
rc = sidtab_context_to_sid(&sidtab,
|
|
&c->context[0],
|
|
&c->sid[0]);
|
|
if (rc)
|
|
goto out;
|
|
}
|
|
*out_sid = c->sid[0];
|
|
} else {
|
|
*out_sid = SECINITSID_NODE;
|
|
}
|
|
|
|
out:
|
|
POLICY_RDUNLOCK;
|
|
return rc;
|
|
}
|
|
|
|
#define SIDS_NEL 25
|
|
|
|
/**
|
|
* security_get_user_sids - Obtain reachable SIDs for a user.
|
|
* @fromsid: starting SID
|
|
* @username: username
|
|
* @sids: array of reachable SIDs for user
|
|
* @nel: number of elements in @sids
|
|
*
|
|
* Generate the set of SIDs for legal security contexts
|
|
* for a given user that can be reached by @fromsid.
|
|
* Set *@sids to point to a dynamically allocated
|
|
* array containing the set of SIDs. Set *@nel to the
|
|
* number of elements in the array.
|
|
*/
|
|
|
|
int security_get_user_sids(u32 fromsid,
|
|
char *username,
|
|
u32 **sids,
|
|
u32 *nel)
|
|
{
|
|
struct context *fromcon, usercon;
|
|
u32 *mysids, *mysids2, sid;
|
|
u32 mynel = 0, maxnel = SIDS_NEL;
|
|
struct user_datum *user;
|
|
struct role_datum *role;
|
|
struct av_decision avd;
|
|
struct ebitmap_node *rnode, *tnode;
|
|
int rc = 0, i, j;
|
|
|
|
if (!ss_initialized) {
|
|
*sids = NULL;
|
|
*nel = 0;
|
|
goto out;
|
|
}
|
|
|
|
POLICY_RDLOCK;
|
|
|
|
fromcon = sidtab_search(&sidtab, fromsid);
|
|
if (!fromcon) {
|
|
rc = -EINVAL;
|
|
goto out_unlock;
|
|
}
|
|
|
|
user = hashtab_search(policydb.p_users.table, username);
|
|
if (!user) {
|
|
rc = -EINVAL;
|
|
goto out_unlock;
|
|
}
|
|
usercon.user = user->value;
|
|
|
|
mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
|
|
if (!mysids) {
|
|
rc = -ENOMEM;
|
|
goto out_unlock;
|
|
}
|
|
|
|
ebitmap_for_each_bit(&user->roles, rnode, i) {
|
|
if (!ebitmap_node_get_bit(rnode, i))
|
|
continue;
|
|
role = policydb.role_val_to_struct[i];
|
|
usercon.role = i+1;
|
|
ebitmap_for_each_bit(&role->types, tnode, j) {
|
|
if (!ebitmap_node_get_bit(tnode, j))
|
|
continue;
|
|
usercon.type = j+1;
|
|
|
|
if (mls_setup_user_range(fromcon, user, &usercon))
|
|
continue;
|
|
|
|
rc = context_struct_compute_av(fromcon, &usercon,
|
|
SECCLASS_PROCESS,
|
|
PROCESS__TRANSITION,
|
|
&avd);
|
|
if (rc || !(avd.allowed & PROCESS__TRANSITION))
|
|
continue;
|
|
rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
|
|
if (rc) {
|
|
kfree(mysids);
|
|
goto out_unlock;
|
|
}
|
|
if (mynel < maxnel) {
|
|
mysids[mynel++] = sid;
|
|
} else {
|
|
maxnel += SIDS_NEL;
|
|
mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
|
|
if (!mysids2) {
|
|
rc = -ENOMEM;
|
|
kfree(mysids);
|
|
goto out_unlock;
|
|
}
|
|
memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
|
|
kfree(mysids);
|
|
mysids = mysids2;
|
|
mysids[mynel++] = sid;
|
|
}
|
|
}
|
|
}
|
|
|
|
*sids = mysids;
|
|
*nel = mynel;
|
|
|
|
out_unlock:
|
|
POLICY_RDUNLOCK;
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
/**
|
|
* security_genfs_sid - Obtain a SID for a file in a filesystem
|
|
* @fstype: filesystem type
|
|
* @path: path from root of mount
|
|
* @sclass: file security class
|
|
* @sid: SID for path
|
|
*
|
|
* Obtain a SID to use for a file in a filesystem that
|
|
* cannot support xattr or use a fixed labeling behavior like
|
|
* transition SIDs or task SIDs.
|
|
*/
|
|
int security_genfs_sid(const char *fstype,
|
|
char *path,
|
|
u16 sclass,
|
|
u32 *sid)
|
|
{
|
|
int len;
|
|
struct genfs *genfs;
|
|
struct ocontext *c;
|
|
int rc = 0, cmp = 0;
|
|
|
|
POLICY_RDLOCK;
|
|
|
|
for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
|
|
cmp = strcmp(fstype, genfs->fstype);
|
|
if (cmp <= 0)
|
|
break;
|
|
}
|
|
|
|
if (!genfs || cmp) {
|
|
*sid = SECINITSID_UNLABELED;
|
|
rc = -ENOENT;
|
|
goto out;
|
|
}
|
|
|
|
for (c = genfs->head; c; c = c->next) {
|
|
len = strlen(c->u.name);
|
|
if ((!c->v.sclass || sclass == c->v.sclass) &&
|
|
(strncmp(c->u.name, path, len) == 0))
|
|
break;
|
|
}
|
|
|
|
if (!c) {
|
|
*sid = SECINITSID_UNLABELED;
|
|
rc = -ENOENT;
|
|
goto out;
|
|
}
|
|
|
|
if (!c->sid[0]) {
|
|
rc = sidtab_context_to_sid(&sidtab,
|
|
&c->context[0],
|
|
&c->sid[0]);
|
|
if (rc)
|
|
goto out;
|
|
}
|
|
|
|
*sid = c->sid[0];
|
|
out:
|
|
POLICY_RDUNLOCK;
|
|
return rc;
|
|
}
|
|
|
|
/**
|
|
* security_fs_use - Determine how to handle labeling for a filesystem.
|
|
* @fstype: filesystem type
|
|
* @behavior: labeling behavior
|
|
* @sid: SID for filesystem (superblock)
|
|
*/
|
|
int security_fs_use(
|
|
const char *fstype,
|
|
unsigned int *behavior,
|
|
u32 *sid)
|
|
{
|
|
int rc = 0;
|
|
struct ocontext *c;
|
|
|
|
POLICY_RDLOCK;
|
|
|
|
c = policydb.ocontexts[OCON_FSUSE];
|
|
while (c) {
|
|
if (strcmp(fstype, c->u.name) == 0)
|
|
break;
|
|
c = c->next;
|
|
}
|
|
|
|
if (c) {
|
|
*behavior = c->v.behavior;
|
|
if (!c->sid[0]) {
|
|
rc = sidtab_context_to_sid(&sidtab,
|
|
&c->context[0],
|
|
&c->sid[0]);
|
|
if (rc)
|
|
goto out;
|
|
}
|
|
*sid = c->sid[0];
|
|
} else {
|
|
rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
|
|
if (rc) {
|
|
*behavior = SECURITY_FS_USE_NONE;
|
|
rc = 0;
|
|
} else {
|
|
*behavior = SECURITY_FS_USE_GENFS;
|
|
}
|
|
}
|
|
|
|
out:
|
|
POLICY_RDUNLOCK;
|
|
return rc;
|
|
}
|
|
|
|
int security_get_bools(int *len, char ***names, int **values)
|
|
{
|
|
int i, rc = -ENOMEM;
|
|
|
|
POLICY_RDLOCK;
|
|
*names = NULL;
|
|
*values = NULL;
|
|
|
|
*len = policydb.p_bools.nprim;
|
|
if (!*len) {
|
|
rc = 0;
|
|
goto out;
|
|
}
|
|
|
|
*names = kcalloc(*len, sizeof(char*), GFP_ATOMIC);
|
|
if (!*names)
|
|
goto err;
|
|
|
|
*values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
|
|
if (!*values)
|
|
goto err;
|
|
|
|
for (i = 0; i < *len; i++) {
|
|
size_t name_len;
|
|
(*values)[i] = policydb.bool_val_to_struct[i]->state;
|
|
name_len = strlen(policydb.p_bool_val_to_name[i]) + 1;
|
|
(*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
|
|
if (!(*names)[i])
|
|
goto err;
|
|
strncpy((*names)[i], policydb.p_bool_val_to_name[i], name_len);
|
|
(*names)[i][name_len - 1] = 0;
|
|
}
|
|
rc = 0;
|
|
out:
|
|
POLICY_RDUNLOCK;
|
|
return rc;
|
|
err:
|
|
if (*names) {
|
|
for (i = 0; i < *len; i++)
|
|
kfree((*names)[i]);
|
|
}
|
|
kfree(*values);
|
|
goto out;
|
|
}
|
|
|
|
|
|
int security_set_bools(int len, int *values)
|
|
{
|
|
int i, rc = 0;
|
|
int lenp, seqno = 0;
|
|
struct cond_node *cur;
|
|
|
|
POLICY_WRLOCK;
|
|
|
|
lenp = policydb.p_bools.nprim;
|
|
if (len != lenp) {
|
|
rc = -EFAULT;
|
|
goto out;
|
|
}
|
|
|
|
for (i = 0; i < len; i++) {
|
|
if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
|
|
audit_log(current->audit_context, GFP_ATOMIC,
|
|
AUDIT_MAC_CONFIG_CHANGE,
|
|
"bool=%s val=%d old_val=%d auid=%u",
|
|
policydb.p_bool_val_to_name[i],
|
|
!!values[i],
|
|
policydb.bool_val_to_struct[i]->state,
|
|
audit_get_loginuid(current->audit_context));
|
|
}
|
|
if (values[i]) {
|
|
policydb.bool_val_to_struct[i]->state = 1;
|
|
} else {
|
|
policydb.bool_val_to_struct[i]->state = 0;
|
|
}
|
|
}
|
|
|
|
for (cur = policydb.cond_list; cur != NULL; cur = cur->next) {
|
|
rc = evaluate_cond_node(&policydb, cur);
|
|
if (rc)
|
|
goto out;
|
|
}
|
|
|
|
seqno = ++latest_granting;
|
|
|
|
out:
|
|
POLICY_WRUNLOCK;
|
|
if (!rc) {
|
|
avc_ss_reset(seqno);
|
|
selnl_notify_policyload(seqno);
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
int security_get_bool_value(int bool)
|
|
{
|
|
int rc = 0;
|
|
int len;
|
|
|
|
POLICY_RDLOCK;
|
|
|
|
len = policydb.p_bools.nprim;
|
|
if (bool >= len) {
|
|
rc = -EFAULT;
|
|
goto out;
|
|
}
|
|
|
|
rc = policydb.bool_val_to_struct[bool]->state;
|
|
out:
|
|
POLICY_RDUNLOCK;
|
|
return rc;
|
|
}
|
|
|
|
/*
|
|
* security_sid_mls_copy() - computes a new sid based on the given
|
|
* sid and the mls portion of mls_sid.
|
|
*/
|
|
int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
|
|
{
|
|
struct context *context1;
|
|
struct context *context2;
|
|
struct context newcon;
|
|
char *s;
|
|
u32 len;
|
|
int rc = 0;
|
|
|
|
if (!ss_initialized || !selinux_mls_enabled) {
|
|
*new_sid = sid;
|
|
goto out;
|
|
}
|
|
|
|
context_init(&newcon);
|
|
|
|
POLICY_RDLOCK;
|
|
context1 = sidtab_search(&sidtab, sid);
|
|
if (!context1) {
|
|
printk(KERN_ERR "security_sid_mls_copy: unrecognized SID "
|
|
"%d\n", sid);
|
|
rc = -EINVAL;
|
|
goto out_unlock;
|
|
}
|
|
|
|
context2 = sidtab_search(&sidtab, mls_sid);
|
|
if (!context2) {
|
|
printk(KERN_ERR "security_sid_mls_copy: unrecognized SID "
|
|
"%d\n", mls_sid);
|
|
rc = -EINVAL;
|
|
goto out_unlock;
|
|
}
|
|
|
|
newcon.user = context1->user;
|
|
newcon.role = context1->role;
|
|
newcon.type = context1->type;
|
|
rc = mls_copy_context(&newcon, context2);
|
|
if (rc)
|
|
goto out_unlock;
|
|
|
|
|
|
/* Check the validity of the new context. */
|
|
if (!policydb_context_isvalid(&policydb, &newcon)) {
|
|
rc = convert_context_handle_invalid_context(&newcon);
|
|
if (rc)
|
|
goto bad;
|
|
}
|
|
|
|
rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid);
|
|
goto out_unlock;
|
|
|
|
bad:
|
|
if (!context_struct_to_string(&newcon, &s, &len)) {
|
|
audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
|
|
"security_sid_mls_copy: invalid context %s", s);
|
|
kfree(s);
|
|
}
|
|
|
|
out_unlock:
|
|
POLICY_RDUNLOCK;
|
|
context_destroy(&newcon);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
struct selinux_audit_rule {
|
|
u32 au_seqno;
|
|
struct context au_ctxt;
|
|
};
|
|
|
|
void selinux_audit_rule_free(struct selinux_audit_rule *rule)
|
|
{
|
|
if (rule) {
|
|
context_destroy(&rule->au_ctxt);
|
|
kfree(rule);
|
|
}
|
|
}
|
|
|
|
int selinux_audit_rule_init(u32 field, u32 op, char *rulestr,
|
|
struct selinux_audit_rule **rule)
|
|
{
|
|
struct selinux_audit_rule *tmprule;
|
|
struct role_datum *roledatum;
|
|
struct type_datum *typedatum;
|
|
struct user_datum *userdatum;
|
|
int rc = 0;
|
|
|
|
*rule = NULL;
|
|
|
|
if (!ss_initialized)
|
|
return -ENOTSUPP;
|
|
|
|
switch (field) {
|
|
case AUDIT_SUBJ_USER:
|
|
case AUDIT_SUBJ_ROLE:
|
|
case AUDIT_SUBJ_TYPE:
|
|
case AUDIT_OBJ_USER:
|
|
case AUDIT_OBJ_ROLE:
|
|
case AUDIT_OBJ_TYPE:
|
|
/* only 'equals' and 'not equals' fit user, role, and type */
|
|
if (op != AUDIT_EQUAL && op != AUDIT_NOT_EQUAL)
|
|
return -EINVAL;
|
|
break;
|
|
case AUDIT_SUBJ_SEN:
|
|
case AUDIT_SUBJ_CLR:
|
|
case AUDIT_OBJ_LEV_LOW:
|
|
case AUDIT_OBJ_LEV_HIGH:
|
|
/* we do not allow a range, indicated by the presense of '-' */
|
|
if (strchr(rulestr, '-'))
|
|
return -EINVAL;
|
|
break;
|
|
default:
|
|
/* only the above fields are valid */
|
|
return -EINVAL;
|
|
}
|
|
|
|
tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
|
|
if (!tmprule)
|
|
return -ENOMEM;
|
|
|
|
context_init(&tmprule->au_ctxt);
|
|
|
|
POLICY_RDLOCK;
|
|
|
|
tmprule->au_seqno = latest_granting;
|
|
|
|
switch (field) {
|
|
case AUDIT_SUBJ_USER:
|
|
case AUDIT_OBJ_USER:
|
|
userdatum = hashtab_search(policydb.p_users.table, rulestr);
|
|
if (!userdatum)
|
|
rc = -EINVAL;
|
|
else
|
|
tmprule->au_ctxt.user = userdatum->value;
|
|
break;
|
|
case AUDIT_SUBJ_ROLE:
|
|
case AUDIT_OBJ_ROLE:
|
|
roledatum = hashtab_search(policydb.p_roles.table, rulestr);
|
|
if (!roledatum)
|
|
rc = -EINVAL;
|
|
else
|
|
tmprule->au_ctxt.role = roledatum->value;
|
|
break;
|
|
case AUDIT_SUBJ_TYPE:
|
|
case AUDIT_OBJ_TYPE:
|
|
typedatum = hashtab_search(policydb.p_types.table, rulestr);
|
|
if (!typedatum)
|
|
rc = -EINVAL;
|
|
else
|
|
tmprule->au_ctxt.type = typedatum->value;
|
|
break;
|
|
case AUDIT_SUBJ_SEN:
|
|
case AUDIT_SUBJ_CLR:
|
|
case AUDIT_OBJ_LEV_LOW:
|
|
case AUDIT_OBJ_LEV_HIGH:
|
|
rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC);
|
|
break;
|
|
}
|
|
|
|
POLICY_RDUNLOCK;
|
|
|
|
if (rc) {
|
|
selinux_audit_rule_free(tmprule);
|
|
tmprule = NULL;
|
|
}
|
|
|
|
*rule = tmprule;
|
|
|
|
return rc;
|
|
}
|
|
|
|
int selinux_audit_rule_match(u32 sid, u32 field, u32 op,
|
|
struct selinux_audit_rule *rule,
|
|
struct audit_context *actx)
|
|
{
|
|
struct context *ctxt;
|
|
struct mls_level *level;
|
|
int match = 0;
|
|
|
|
if (!rule) {
|
|
audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
|
|
"selinux_audit_rule_match: missing rule\n");
|
|
return -ENOENT;
|
|
}
|
|
|
|
POLICY_RDLOCK;
|
|
|
|
if (rule->au_seqno < latest_granting) {
|
|
audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
|
|
"selinux_audit_rule_match: stale rule\n");
|
|
match = -ESTALE;
|
|
goto out;
|
|
}
|
|
|
|
ctxt = sidtab_search(&sidtab, sid);
|
|
if (!ctxt) {
|
|
audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
|
|
"selinux_audit_rule_match: unrecognized SID %d\n",
|
|
sid);
|
|
match = -ENOENT;
|
|
goto out;
|
|
}
|
|
|
|
/* a field/op pair that is not caught here will simply fall through
|
|
without a match */
|
|
switch (field) {
|
|
case AUDIT_SUBJ_USER:
|
|
case AUDIT_OBJ_USER:
|
|
switch (op) {
|
|
case AUDIT_EQUAL:
|
|
match = (ctxt->user == rule->au_ctxt.user);
|
|
break;
|
|
case AUDIT_NOT_EQUAL:
|
|
match = (ctxt->user != rule->au_ctxt.user);
|
|
break;
|
|
}
|
|
break;
|
|
case AUDIT_SUBJ_ROLE:
|
|
case AUDIT_OBJ_ROLE:
|
|
switch (op) {
|
|
case AUDIT_EQUAL:
|
|
match = (ctxt->role == rule->au_ctxt.role);
|
|
break;
|
|
case AUDIT_NOT_EQUAL:
|
|
match = (ctxt->role != rule->au_ctxt.role);
|
|
break;
|
|
}
|
|
break;
|
|
case AUDIT_SUBJ_TYPE:
|
|
case AUDIT_OBJ_TYPE:
|
|
switch (op) {
|
|
case AUDIT_EQUAL:
|
|
match = (ctxt->type == rule->au_ctxt.type);
|
|
break;
|
|
case AUDIT_NOT_EQUAL:
|
|
match = (ctxt->type != rule->au_ctxt.type);
|
|
break;
|
|
}
|
|
break;
|
|
case AUDIT_SUBJ_SEN:
|
|
case AUDIT_SUBJ_CLR:
|
|
case AUDIT_OBJ_LEV_LOW:
|
|
case AUDIT_OBJ_LEV_HIGH:
|
|
level = ((field == AUDIT_SUBJ_SEN ||
|
|
field == AUDIT_OBJ_LEV_LOW) ?
|
|
&ctxt->range.level[0] : &ctxt->range.level[1]);
|
|
switch (op) {
|
|
case AUDIT_EQUAL:
|
|
match = mls_level_eq(&rule->au_ctxt.range.level[0],
|
|
level);
|
|
break;
|
|
case AUDIT_NOT_EQUAL:
|
|
match = !mls_level_eq(&rule->au_ctxt.range.level[0],
|
|
level);
|
|
break;
|
|
case AUDIT_LESS_THAN:
|
|
match = (mls_level_dom(&rule->au_ctxt.range.level[0],
|
|
level) &&
|
|
!mls_level_eq(&rule->au_ctxt.range.level[0],
|
|
level));
|
|
break;
|
|
case AUDIT_LESS_THAN_OR_EQUAL:
|
|
match = mls_level_dom(&rule->au_ctxt.range.level[0],
|
|
level);
|
|
break;
|
|
case AUDIT_GREATER_THAN:
|
|
match = (mls_level_dom(level,
|
|
&rule->au_ctxt.range.level[0]) &&
|
|
!mls_level_eq(level,
|
|
&rule->au_ctxt.range.level[0]));
|
|
break;
|
|
case AUDIT_GREATER_THAN_OR_EQUAL:
|
|
match = mls_level_dom(level,
|
|
&rule->au_ctxt.range.level[0]);
|
|
break;
|
|
}
|
|
}
|
|
|
|
out:
|
|
POLICY_RDUNLOCK;
|
|
return match;
|
|
}
|
|
|
|
static int (*aurule_callback)(void) = NULL;
|
|
|
|
static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid,
|
|
u16 class, u32 perms, u32 *retained)
|
|
{
|
|
int err = 0;
|
|
|
|
if (event == AVC_CALLBACK_RESET && aurule_callback)
|
|
err = aurule_callback();
|
|
return err;
|
|
}
|
|
|
|
static int __init aurule_init(void)
|
|
{
|
|
int err;
|
|
|
|
err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET,
|
|
SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0);
|
|
if (err)
|
|
panic("avc_add_callback() failed, error %d\n", err);
|
|
|
|
return err;
|
|
}
|
|
__initcall(aurule_init);
|
|
|
|
void selinux_audit_set_callback(int (*callback)(void))
|
|
{
|
|
aurule_callback = callback;
|
|
}
|
|
|
|
#ifdef CONFIG_NETLABEL
|
|
/*
|
|
* This is the structure we store inside the NetLabel cache block.
|
|
*/
|
|
#define NETLBL_CACHE(x) ((struct netlbl_cache *)(x))
|
|
#define NETLBL_CACHE_T_NONE 0
|
|
#define NETLBL_CACHE_T_SID 1
|
|
#define NETLBL_CACHE_T_MLS 2
|
|
struct netlbl_cache {
|
|
u32 type;
|
|
union {
|
|
u32 sid;
|
|
struct mls_range mls_label;
|
|
} data;
|
|
};
|
|
|
|
/**
|
|
* selinux_netlbl_cache_free - Free the NetLabel cached data
|
|
* @data: the data to free
|
|
*
|
|
* Description:
|
|
* This function is intended to be used as the free() callback inside the
|
|
* netlbl_lsm_cache structure.
|
|
*
|
|
*/
|
|
static void selinux_netlbl_cache_free(const void *data)
|
|
{
|
|
struct netlbl_cache *cache = NETLBL_CACHE(data);
|
|
switch (cache->type) {
|
|
case NETLBL_CACHE_T_MLS:
|
|
ebitmap_destroy(&cache->data.mls_label.level[0].cat);
|
|
break;
|
|
}
|
|
kfree(data);
|
|
}
|
|
|
|
/**
|
|
* selinux_netlbl_cache_add - Add an entry to the NetLabel cache
|
|
* @skb: the packet
|
|
* @ctx: the SELinux context
|
|
*
|
|
* Description:
|
|
* Attempt to cache the context in @ctx, which was derived from the packet in
|
|
* @skb, in the NetLabel subsystem cache.
|
|
*
|
|
*/
|
|
static void selinux_netlbl_cache_add(struct sk_buff *skb, struct context *ctx)
|
|
{
|
|
struct netlbl_cache *cache = NULL;
|
|
struct netlbl_lsm_secattr secattr;
|
|
|
|
netlbl_secattr_init(&secattr);
|
|
|
|
cache = kzalloc(sizeof(*cache), GFP_ATOMIC);
|
|
if (cache == NULL)
|
|
goto netlbl_cache_add_failure;
|
|
secattr.cache.free = selinux_netlbl_cache_free;
|
|
secattr.cache.data = (void *)cache;
|
|
|
|
cache->type = NETLBL_CACHE_T_MLS;
|
|
if (ebitmap_cpy(&cache->data.mls_label.level[0].cat,
|
|
&ctx->range.level[0].cat) != 0)
|
|
goto netlbl_cache_add_failure;
|
|
cache->data.mls_label.level[1].cat.highbit =
|
|
cache->data.mls_label.level[0].cat.highbit;
|
|
cache->data.mls_label.level[1].cat.node =
|
|
cache->data.mls_label.level[0].cat.node;
|
|
cache->data.mls_label.level[0].sens = ctx->range.level[0].sens;
|
|
cache->data.mls_label.level[1].sens = ctx->range.level[0].sens;
|
|
|
|
if (netlbl_cache_add(skb, &secattr) != 0)
|
|
goto netlbl_cache_add_failure;
|
|
|
|
return;
|
|
|
|
netlbl_cache_add_failure:
|
|
netlbl_secattr_destroy(&secattr, 1);
|
|
}
|
|
|
|
/**
|
|
* selinux_netlbl_cache_invalidate - Invalidate the NetLabel cache
|
|
*
|
|
* Description:
|
|
* Invalidate the NetLabel security attribute mapping cache.
|
|
*
|
|
*/
|
|
void selinux_netlbl_cache_invalidate(void)
|
|
{
|
|
netlbl_cache_invalidate();
|
|
}
|
|
|
|
/**
|
|
* selinux_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
|
|
* @skb: the network packet
|
|
* @secattr: the NetLabel packet security attributes
|
|
* @base_sid: the SELinux SID to use as a context for MLS only attributes
|
|
* @sid: the SELinux SID
|
|
*
|
|
* Description:
|
|
* Convert the given NetLabel packet security attributes in @secattr into a
|
|
* SELinux SID. If the @secattr field does not contain a full SELinux
|
|
* SID/context then use the context in @base_sid as the foundation. If @skb
|
|
* is not NULL attempt to cache as much data as possibile. Returns zero on
|
|
* success, negative values on failure.
|
|
*
|
|
*/
|
|
static int selinux_netlbl_secattr_to_sid(struct sk_buff *skb,
|
|
struct netlbl_lsm_secattr *secattr,
|
|
u32 base_sid,
|
|
u32 *sid)
|
|
{
|
|
int rc = -EIDRM;
|
|
struct context *ctx;
|
|
struct context ctx_new;
|
|
struct netlbl_cache *cache;
|
|
|
|
POLICY_RDLOCK;
|
|
|
|
if (secattr->cache.data) {
|
|
cache = NETLBL_CACHE(secattr->cache.data);
|
|
switch (cache->type) {
|
|
case NETLBL_CACHE_T_SID:
|
|
*sid = cache->data.sid;
|
|
rc = 0;
|
|
break;
|
|
case NETLBL_CACHE_T_MLS:
|
|
ctx = sidtab_search(&sidtab, base_sid);
|
|
if (ctx == NULL)
|
|
goto netlbl_secattr_to_sid_return;
|
|
|
|
ctx_new.user = ctx->user;
|
|
ctx_new.role = ctx->role;
|
|
ctx_new.type = ctx->type;
|
|
ctx_new.range.level[0].sens =
|
|
cache->data.mls_label.level[0].sens;
|
|
ctx_new.range.level[0].cat.highbit =
|
|
cache->data.mls_label.level[0].cat.highbit;
|
|
ctx_new.range.level[0].cat.node =
|
|
cache->data.mls_label.level[0].cat.node;
|
|
ctx_new.range.level[1].sens =
|
|
cache->data.mls_label.level[1].sens;
|
|
ctx_new.range.level[1].cat.highbit =
|
|
cache->data.mls_label.level[1].cat.highbit;
|
|
ctx_new.range.level[1].cat.node =
|
|
cache->data.mls_label.level[1].cat.node;
|
|
|
|
rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
|
|
break;
|
|
default:
|
|
goto netlbl_secattr_to_sid_return;
|
|
}
|
|
} else if (secattr->mls_lvl_vld) {
|
|
ctx = sidtab_search(&sidtab, base_sid);
|
|
if (ctx == NULL)
|
|
goto netlbl_secattr_to_sid_return;
|
|
|
|
ctx_new.user = ctx->user;
|
|
ctx_new.role = ctx->role;
|
|
ctx_new.type = ctx->type;
|
|
mls_import_lvl(&ctx_new, secattr->mls_lvl, secattr->mls_lvl);
|
|
if (secattr->mls_cat) {
|
|
if (mls_import_cat(&ctx_new,
|
|
secattr->mls_cat,
|
|
secattr->mls_cat_len,
|
|
NULL,
|
|
0) != 0)
|
|
goto netlbl_secattr_to_sid_return;
|
|
ctx_new.range.level[1].cat.highbit =
|
|
ctx_new.range.level[0].cat.highbit;
|
|
ctx_new.range.level[1].cat.node =
|
|
ctx_new.range.level[0].cat.node;
|
|
} else {
|
|
ebitmap_init(&ctx_new.range.level[0].cat);
|
|
ebitmap_init(&ctx_new.range.level[1].cat);
|
|
}
|
|
if (mls_context_isvalid(&policydb, &ctx_new) != 1)
|
|
goto netlbl_secattr_to_sid_return_cleanup;
|
|
|
|
rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
|
|
if (rc != 0)
|
|
goto netlbl_secattr_to_sid_return_cleanup;
|
|
|
|
if (skb != NULL)
|
|
selinux_netlbl_cache_add(skb, &ctx_new);
|
|
ebitmap_destroy(&ctx_new.range.level[0].cat);
|
|
} else {
|
|
*sid = SECINITSID_UNLABELED;
|
|
rc = 0;
|
|
}
|
|
|
|
netlbl_secattr_to_sid_return:
|
|
POLICY_RDUNLOCK;
|
|
return rc;
|
|
netlbl_secattr_to_sid_return_cleanup:
|
|
ebitmap_destroy(&ctx_new.range.level[0].cat);
|
|
goto netlbl_secattr_to_sid_return;
|
|
}
|
|
|
|
/**
|
|
* selinux_netlbl_skbuff_getsid - Get the sid of a packet using NetLabel
|
|
* @skb: the packet
|
|
* @base_sid: the SELinux SID to use as a context for MLS only attributes
|
|
* @sid: the SID
|
|
*
|
|
* Description:
|
|
* Call the NetLabel mechanism to get the security attributes of the given
|
|
* packet and use those attributes to determine the correct context/SID to
|
|
* assign to the packet. Returns zero on success, negative values on failure.
|
|
*
|
|
*/
|
|
static int selinux_netlbl_skbuff_getsid(struct sk_buff *skb,
|
|
u32 base_sid,
|
|
u32 *sid)
|
|
{
|
|
int rc;
|
|
struct netlbl_lsm_secattr secattr;
|
|
|
|
netlbl_secattr_init(&secattr);
|
|
rc = netlbl_skbuff_getattr(skb, &secattr);
|
|
if (rc == 0)
|
|
rc = selinux_netlbl_secattr_to_sid(skb,
|
|
&secattr,
|
|
base_sid,
|
|
sid);
|
|
netlbl_secattr_destroy(&secattr, 0);
|
|
|
|
return rc;
|
|
}
|
|
|
|
/**
|
|
* selinux_netlbl_socket_setsid - Label a socket using the NetLabel mechanism
|
|
* @sock: the socket to label
|
|
* @sid: the SID to use
|
|
*
|
|
* Description:
|
|
* Attempt to label a socket using the NetLabel mechanism using the given
|
|
* SID. Returns zero values on success, negative values on failure.
|
|
*
|
|
*/
|
|
static int selinux_netlbl_socket_setsid(struct socket *sock, u32 sid)
|
|
{
|
|
int rc = -ENOENT;
|
|
struct sk_security_struct *sksec = sock->sk->sk_security;
|
|
struct netlbl_lsm_secattr secattr;
|
|
struct context *ctx;
|
|
|
|
if (!ss_initialized)
|
|
return 0;
|
|
|
|
POLICY_RDLOCK;
|
|
|
|
ctx = sidtab_search(&sidtab, sid);
|
|
if (ctx == NULL)
|
|
goto netlbl_socket_setsid_return;
|
|
|
|
netlbl_secattr_init(&secattr);
|
|
secattr.domain = kstrdup(policydb.p_type_val_to_name[ctx->type - 1],
|
|
GFP_ATOMIC);
|
|
mls_export_lvl(ctx, &secattr.mls_lvl, NULL);
|
|
secattr.mls_lvl_vld = 1;
|
|
mls_export_cat(ctx,
|
|
&secattr.mls_cat,
|
|
&secattr.mls_cat_len,
|
|
NULL,
|
|
NULL);
|
|
|
|
rc = netlbl_socket_setattr(sock, &secattr);
|
|
if (rc == 0)
|
|
sksec->nlbl_state = NLBL_LABELED;
|
|
|
|
netlbl_secattr_destroy(&secattr, 0);
|
|
|
|
netlbl_socket_setsid_return:
|
|
POLICY_RDUNLOCK;
|
|
return rc;
|
|
}
|
|
|
|
/**
|
|
* selinux_netlbl_sk_security_init - Setup the NetLabel fields
|
|
* @ssec: the sk_security_struct
|
|
* @family: the socket family
|
|
*
|
|
* Description:
|
|
* Called when a new sk_security_struct is allocated to initialize the NetLabel
|
|
* fields.
|
|
*
|
|
*/
|
|
void selinux_netlbl_sk_security_init(struct sk_security_struct *ssec,
|
|
int family)
|
|
{
|
|
if (family == PF_INET)
|
|
ssec->nlbl_state = NLBL_REQUIRE;
|
|
else
|
|
ssec->nlbl_state = NLBL_UNSET;
|
|
}
|
|
|
|
/**
|
|
* selinux_netlbl_sk_clone_security - Copy the NetLabel fields
|
|
* @ssec: the original sk_security_struct
|
|
* @newssec: the cloned sk_security_struct
|
|
*
|
|
* Description:
|
|
* Clone the NetLabel specific sk_security_struct fields from @ssec to
|
|
* @newssec.
|
|
*
|
|
*/
|
|
void selinux_netlbl_sk_clone_security(struct sk_security_struct *ssec,
|
|
struct sk_security_struct *newssec)
|
|
{
|
|
newssec->sclass = ssec->sclass;
|
|
if (ssec->nlbl_state != NLBL_UNSET)
|
|
newssec->nlbl_state = NLBL_REQUIRE;
|
|
else
|
|
newssec->nlbl_state = NLBL_UNSET;
|
|
}
|
|
|
|
/**
|
|
* selinux_netlbl_socket_post_create - Label a socket using NetLabel
|
|
* @sock: the socket to label
|
|
* @sock_family: the socket family
|
|
* @sid: the SID to use
|
|
*
|
|
* Description:
|
|
* Attempt to label a socket using the NetLabel mechanism using the given
|
|
* SID. Returns zero values on success, negative values on failure.
|
|
*
|
|
*/
|
|
int selinux_netlbl_socket_post_create(struct socket *sock,
|
|
int sock_family,
|
|
u32 sid)
|
|
{
|
|
struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
|
|
struct sk_security_struct *sksec = sock->sk->sk_security;
|
|
|
|
sksec->sclass = isec->sclass;
|
|
|
|
if (sock_family != PF_INET)
|
|
return 0;
|
|
|
|
sksec->nlbl_state = NLBL_REQUIRE;
|
|
return selinux_netlbl_socket_setsid(sock, sid);
|
|
}
|
|
|
|
/**
|
|
* selinux_netlbl_sock_graft - Netlabel the new socket
|
|
* @sk: the new connection
|
|
* @sock: the new socket
|
|
*
|
|
* Description:
|
|
* The connection represented by @sk is being grafted onto @sock so set the
|
|
* socket's NetLabel to match the SID of @sk.
|
|
*
|
|
*/
|
|
void selinux_netlbl_sock_graft(struct sock *sk, struct socket *sock)
|
|
{
|
|
struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
struct netlbl_lsm_secattr secattr;
|
|
u32 nlbl_peer_sid;
|
|
|
|
sksec->sclass = isec->sclass;
|
|
|
|
if (sk->sk_family != PF_INET)
|
|
return;
|
|
|
|
netlbl_secattr_init(&secattr);
|
|
if (netlbl_sock_getattr(sk, &secattr) == 0 &&
|
|
selinux_netlbl_secattr_to_sid(NULL,
|
|
&secattr,
|
|
sksec->sid,
|
|
&nlbl_peer_sid) == 0)
|
|
sksec->peer_sid = nlbl_peer_sid;
|
|
netlbl_secattr_destroy(&secattr, 0);
|
|
|
|
sksec->nlbl_state = NLBL_REQUIRE;
|
|
|
|
/* Try to set the NetLabel on the socket to save time later, if we fail
|
|
* here we will pick up the pieces in later calls to
|
|
* selinux_netlbl_inode_permission(). */
|
|
selinux_netlbl_socket_setsid(sock, sksec->sid);
|
|
}
|
|
|
|
/**
|
|
* selinux_netlbl_inet_conn_request - Handle a new connection request
|
|
* @skb: the packet
|
|
* @sock_sid: the SID of the parent socket
|
|
*
|
|
* Description:
|
|
* If present, use the security attributes of the packet in @skb and the
|
|
* parent sock's SID to arrive at a SID for the new child sock. Returns the
|
|
* SID of the connection or SECSID_NULL on failure.
|
|
*
|
|
*/
|
|
u32 selinux_netlbl_inet_conn_request(struct sk_buff *skb, u32 sock_sid)
|
|
{
|
|
int rc;
|
|
u32 peer_sid;
|
|
|
|
rc = selinux_netlbl_skbuff_getsid(skb, sock_sid, &peer_sid);
|
|
if (rc != 0)
|
|
return SECSID_NULL;
|
|
|
|
if (peer_sid == SECINITSID_UNLABELED)
|
|
return SECSID_NULL;
|
|
|
|
return peer_sid;
|
|
}
|
|
|
|
/**
|
|
* selinux_netlbl_inode_permission - Verify the socket is NetLabel labeled
|
|
* @inode: the file descriptor's inode
|
|
* @mask: the permission mask
|
|
*
|
|
* Description:
|
|
* Looks at a file's inode and if it is marked as a socket protected by
|
|
* NetLabel then verify that the socket has been labeled, if not try to label
|
|
* the socket now with the inode's SID. Returns zero on success, negative
|
|
* values on failure.
|
|
*
|
|
*/
|
|
int selinux_netlbl_inode_permission(struct inode *inode, int mask)
|
|
{
|
|
int rc;
|
|
struct inode_security_struct *isec;
|
|
struct sk_security_struct *sksec;
|
|
struct socket *sock;
|
|
|
|
if (!S_ISSOCK(inode->i_mode))
|
|
return 0;
|
|
|
|
sock = SOCKET_I(inode);
|
|
isec = inode->i_security;
|
|
sksec = sock->sk->sk_security;
|
|
down(&isec->sem);
|
|
if (unlikely(sksec->nlbl_state == NLBL_REQUIRE &&
|
|
(mask & (MAY_WRITE | MAY_APPEND)))) {
|
|
lock_sock(sock->sk);
|
|
rc = selinux_netlbl_socket_setsid(sock, sksec->sid);
|
|
release_sock(sock->sk);
|
|
} else
|
|
rc = 0;
|
|
up(&isec->sem);
|
|
|
|
return rc;
|
|
}
|
|
|
|
/**
|
|
* selinux_netlbl_sock_rcv_skb - Do an inbound access check using NetLabel
|
|
* @sksec: the sock's sk_security_struct
|
|
* @skb: the packet
|
|
* @ad: the audit data
|
|
*
|
|
* Description:
|
|
* Fetch the NetLabel security attributes from @skb and perform an access check
|
|
* against the receiving socket. Returns zero on success, negative values on
|
|
* error.
|
|
*
|
|
*/
|
|
int selinux_netlbl_sock_rcv_skb(struct sk_security_struct *sksec,
|
|
struct sk_buff *skb,
|
|
struct avc_audit_data *ad)
|
|
{
|
|
int rc;
|
|
u32 netlbl_sid;
|
|
u32 recv_perm;
|
|
|
|
rc = selinux_netlbl_skbuff_getsid(skb, SECINITSID_NETMSG, &netlbl_sid);
|
|
if (rc != 0)
|
|
return rc;
|
|
|
|
if (netlbl_sid == SECINITSID_UNLABELED)
|
|
return 0;
|
|
|
|
switch (sksec->sclass) {
|
|
case SECCLASS_UDP_SOCKET:
|
|
recv_perm = UDP_SOCKET__RECVFROM;
|
|
break;
|
|
case SECCLASS_TCP_SOCKET:
|
|
recv_perm = TCP_SOCKET__RECVFROM;
|
|
break;
|
|
default:
|
|
recv_perm = RAWIP_SOCKET__RECVFROM;
|
|
}
|
|
|
|
rc = avc_has_perm(sksec->sid,
|
|
netlbl_sid,
|
|
sksec->sclass,
|
|
recv_perm,
|
|
ad);
|
|
if (rc == 0)
|
|
return 0;
|
|
|
|
netlbl_skbuff_err(skb, rc);
|
|
return rc;
|
|
}
|
|
|
|
/**
|
|
* selinux_netlbl_socket_getpeersec_stream - Return the connected peer's SID
|
|
* @sock: the socket
|
|
*
|
|
* Description:
|
|
* Examine @sock to find the connected peer's SID. Returns the SID on success
|
|
* or SECSID_NULL on error.
|
|
*
|
|
*/
|
|
u32 selinux_netlbl_socket_getpeersec_stream(struct socket *sock)
|
|
{
|
|
struct sk_security_struct *sksec = sock->sk->sk_security;
|
|
|
|
if (sksec->peer_sid == SECINITSID_UNLABELED)
|
|
return SECSID_NULL;
|
|
|
|
return sksec->peer_sid;
|
|
}
|
|
|
|
/**
|
|
* selinux_netlbl_socket_getpeersec_dgram - Return the SID of a NetLabel packet
|
|
* @skb: the packet
|
|
*
|
|
* Description:
|
|
* Examine @skb to find the SID assigned to it by NetLabel. Returns the SID on
|
|
* success, SECSID_NULL on error.
|
|
*
|
|
*/
|
|
u32 selinux_netlbl_socket_getpeersec_dgram(struct sk_buff *skb)
|
|
{
|
|
int peer_sid;
|
|
struct sock *sk = skb->sk;
|
|
struct inode_security_struct *isec;
|
|
|
|
if (sk == NULL || sk->sk_socket == NULL)
|
|
return SECSID_NULL;
|
|
|
|
isec = SOCK_INODE(sk->sk_socket)->i_security;
|
|
if (selinux_netlbl_skbuff_getsid(skb, isec->sid, &peer_sid) != 0)
|
|
return SECSID_NULL;
|
|
if (peer_sid == SECINITSID_UNLABELED)
|
|
return SECSID_NULL;
|
|
|
|
return peer_sid;
|
|
}
|
|
#endif /* CONFIG_NETLABEL */
|