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272cd7a8c6
This patch is targeted for the smack-next tree. Smack access checks suffer from two significant performance issues. In cases where there are large numbers of rules the search of the single list of rules is wasteful. Comparing the string values of the smack labels is less efficient than a numeric comparison would. These changes take advantage of the Smack label list, which maintains the mapping of Smack labels to secids and optional CIPSO labels. Because the labels are kept perpetually, an access check can be done strictly based on the address of the label in the list without ever looking at the label itself. Rather than keeping one global list of rules the rules with a particular subject label can be based off of that label list entry. The access check need never look at entries that do not use the current subject label. This requires that packets coming off the network with CIPSO direct Smack labels that have never been seen before be treated carefully. The only case where they could be delivered is where the receiving socket has an IPIN star label, so that case is explicitly addressed. On a system with 39,800 rules (200 labels in all permutations) a system with this patch runs an access speed test in 5% of the time of the old version. That should be a best case improvement. If all of the rules are associated with the same subject label and all of the accesses are for processes with that label (unlikely) the improvement is about 30%. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> |
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| .. | ||
| Kconfig | ||
| Makefile | ||
| smack_access.c | ||
| smack_lsm.c | ||
| smack.h | ||
| smackfs.c | ||