NetLabel: make netlbl_lsm_secattr struct easier/quicker to understand
The existing netlbl_lsm_secattr struct required the LSM to check all of the
fields to determine if any security attributes were present resulting in a lot
of work in the common case of no attributes. This patch adds a 'flags' field
which is used to indicate which attributes are present in the structure; this
should allow the LSM to do a quick comparison to determine if the structure
holds any security attributes.
Example:
if (netlbl_lsm_secattr->flags)
/* security attributes present */
else
/* NO security attributes present */
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c
index 095038a..f0a0785 100644
--- a/net/ipv4/cipso_ipv4.c
+++ b/net/ipv4/cipso_ipv4.c
@@ -319,6 +319,7 @@
entry->activity += 1;
atomic_inc(&entry->lsm_data->refcount);
secattr->cache = entry->lsm_data;
+ secattr->flags |= NETLBL_SECATTR_CACHE;
if (prev_entry == NULL) {
spin_unlock_bh(&cipso_v4_cache[bkt].lock);
return 0;
@@ -991,12 +992,15 @@
unsigned char **buffer,
u32 *buffer_len)
{
- int ret_val = -EPERM;
+ int ret_val;
unsigned char *buf = NULL;
u32 buf_len;
u32 level;
- if (secattr->mls_cat) {
+ if ((secattr->flags & NETLBL_SECATTR_MLS_LVL) == 0)
+ return -EPERM;
+
+ if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
buf = kzalloc(CIPSO_V4_HDR_LEN + 4 + CIPSO_V4_TAG1_CAT_LEN,
GFP_ATOMIC);
if (buf == NULL)
@@ -1013,10 +1017,10 @@
/* This will send packets using the "optimized" format when
* possibile as specified in section 3.4.2.6 of the
* CIPSO draft. */
- if (cipso_v4_rbm_optfmt && (ret_val > 0 && ret_val < 10))
- ret_val = 10;
-
- buf_len = 4 + ret_val;
+ if (cipso_v4_rbm_optfmt && ret_val > 0 && ret_val <= 10)
+ buf_len = 14;
+ else
+ buf_len = 4 + ret_val;
} else {
buf = kzalloc(CIPSO_V4_HDR_LEN + 4, GFP_ATOMIC);
if (buf == NULL)
@@ -1070,7 +1074,7 @@
if (ret_val != 0)
return ret_val;
secattr->mls_lvl = level;
- secattr->mls_lvl_vld = 1;
+ secattr->flags |= NETLBL_SECATTR_MLS_LVL;
if (tag_len > 4) {
switch (doi_def->type) {
@@ -1094,8 +1098,10 @@
if (ret_val < 0) {
kfree(secattr->mls_cat);
return ret_val;
+ } else if (ret_val > 0) {
+ secattr->mls_cat_len = ret_val;
+ secattr->flags |= NETLBL_SECATTR_MLS_CAT;
}
- secattr->mls_cat_len = ret_val;
}
return 0;