From f9df6458218f4fe8a1c3bf0af89c1fa9eaf0db39 Mon Sep 17 00:00:00 2001 From: Andrew Perepechko Date: Thu, 24 Dec 2015 11:09:41 -0500 Subject: selinux: export validatetrans decisions Make validatetrans decisions available through selinuxfs. "/validatetrans" is added to selinuxfs for this purpose. This functionality is needed by file system servers implemented in userspace or kernelspace without the VFS layer. Writing "$oldcontext $newcontext $tclass $taskcontext" to /validatetrans is expected to return 0 if the transition is allowed and -EPERM otherwise. Signed-off-by: Andrew Perepechko CC: andrew.perepechko@seagate.com Acked-by: Stephen Smalley Signed-off-by: Paul Moore --- security/selinux/ss/services.c | 34 +++++++++++++++++++++++++++------- 1 file changed, 27 insertions(+), 7 deletions(-) (limited to 'security/selinux/ss/services.c') diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index ebb5eb3c318c..ebda97333f1b 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -778,8 +778,8 @@ out: return -EPERM; } -int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid, - u16 orig_tclass) +static int security_compute_validatetrans(u32 oldsid, u32 newsid, u32 tasksid, + u16 orig_tclass, bool user) { struct context *ocontext; struct context *ncontext; @@ -794,11 +794,12 @@ int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid, read_lock(&policy_rwlock); - tclass = unmap_class(orig_tclass); + if (!user) + tclass = unmap_class(orig_tclass); + else + tclass = orig_tclass; if (!tclass || tclass > policydb.p_classes.nprim) { - printk(KERN_ERR "SELinux: %s: unrecognized class %d\n", - __func__, tclass); rc = -EINVAL; goto out; } @@ -832,8 +833,13 @@ int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid, while (constraint) { if (!constraint_expr_eval(ocontext, ncontext, tcontext, constraint->expr)) { - rc = security_validtrans_handle_fail(ocontext, ncontext, - tcontext, tclass); + if (user) + rc = -EPERM; + else + rc = security_validtrans_handle_fail(ocontext, + ncontext, + tcontext, + tclass); goto out; } constraint = constraint->next; @@ -844,6 +850,20 @@ out: return rc; } +int security_validate_transition_user(u32 oldsid, u32 newsid, u32 tasksid, + u16 tclass) +{ + return security_compute_validatetrans(oldsid, newsid, tasksid, + tclass, true); +} + +int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid, + u16 orig_tclass) +{ + return security_compute_validatetrans(oldsid, newsid, tasksid, + orig_tclass, false); +} + /* * security_bounded_transition - check whether the given * transition is directed to bounded, or not. -- cgit v1.2.3-59-g8ed1b