From aa893269de6277b44be88e25dcd5331c934c29c4 Mon Sep 17 00:00:00 2001 From: Eric Paris Date: Tue, 20 Mar 2012 14:35:12 -0400 Subject: SELinux: allow default source/target selectors for user/role/range When new objects are created we have great and flexible rules to determine the type of the new object. We aren't quite as flexible or mature when it comes to determining the user, role, and range. This patch adds a new ability to specify the place a new objects user, role, and range should come from. For users and roles it can come from either the source or the target of the operation. aka for files the user can either come from the source (the running process and todays default) or it can come from the target (aka the parent directory of the new file) examples always are done with directory context: system_u:object_r:mnt_t:s0-s0:c0.c512 process context: unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 [no rule] unconfined_u:object_r:mnt_t:s0 test_none [default user source] unconfined_u:object_r:mnt_t:s0 test_user_source [default user target] system_u:object_r:mnt_t:s0 test_user_target [default role source] unconfined_u:unconfined_r:mnt_t:s0 test_role_source [default role target] unconfined_u:object_r:mnt_t:s0 test_role_target [default range source low] unconfined_u:object_r:mnt_t:s0 test_range_source_low [default range source high] unconfined_u:object_r:mnt_t:s0:c0.c1023 test_range_source_high [default range source low-high] unconfined_u:object_r:mnt_t:s0-s0:c0.c1023 test_range_source_low-high [default range target low] unconfined_u:object_r:mnt_t:s0 test_range_target_low [default range target high] unconfined_u:object_r:mnt_t:s0:c0.c512 test_range_target_high [default range target low-high] unconfined_u:object_r:mnt_t:s0-s0:c0.c512 test_range_target_low-high Signed-off-by: Eric Paris --- security/selinux/ss/mls.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) (limited to 'security/selinux/ss/mls.c') diff --git a/security/selinux/ss/mls.c b/security/selinux/ss/mls.c index fbf9c5816c71..40de8d3f208e 100644 --- a/security/selinux/ss/mls.c +++ b/security/selinux/ss/mls.c @@ -517,6 +517,8 @@ int mls_compute_sid(struct context *scontext, { struct range_trans rtr; struct mls_range *r; + struct class_datum *cladatum; + int default_range = 0; if (!policydb.mls_enabled) return 0; @@ -530,6 +532,28 @@ int mls_compute_sid(struct context *scontext, r = hashtab_search(policydb.range_tr, &rtr); if (r) return mls_range_set(newcontext, r); + + if (tclass && tclass <= policydb.p_classes.nprim) { + cladatum = policydb.class_val_to_struct[tclass - 1]; + if (cladatum) + default_range = cladatum->default_range; + } + + switch (default_range) { + case DEFAULT_SOURCE_LOW: + return mls_context_cpy_low(newcontext, scontext); + case DEFAULT_SOURCE_HIGH: + return mls_context_cpy_high(newcontext, scontext); + case DEFAULT_SOURCE_LOW_HIGH: + return mls_context_cpy(newcontext, scontext); + case DEFAULT_TARGET_LOW: + return mls_context_cpy_low(newcontext, tcontext); + case DEFAULT_TARGET_HIGH: + return mls_context_cpy_high(newcontext, tcontext); + case DEFAULT_TARGET_LOW_HIGH: + return mls_context_cpy(newcontext, tcontext); + } + /* Fallthrough */ case AVTAB_CHANGE: if ((tclass == policydb.process_class) || (sock == true)) -- cgit v1.2.3-59-g8ed1b