[PATCH] audit syscall classes
Allow to tie upper bits of syscall bitmap in audit rules to kernel-defined
sets of syscalls. Infrastructure, a couple of classes (with 32bit counterparts
for biarch targets) and actual tie-in on i386, amd64 and ia64.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index 7f2ea8b..5b4e162 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -279,6 +279,29 @@
return 0;
}
+static __u32 *classes[AUDIT_SYSCALL_CLASSES];
+
+int __init audit_register_class(int class, unsigned *list)
+{
+ __u32 *p = kzalloc(AUDIT_BITMASK_SIZE * sizeof(__u32), GFP_KERNEL);
+ if (!p)
+ return -ENOMEM;
+ while (*list != ~0U) {
+ unsigned n = *list++;
+ if (n >= AUDIT_BITMASK_SIZE * 32 - AUDIT_SYSCALL_CLASSES) {
+ kfree(p);
+ return -EINVAL;
+ }
+ p[AUDIT_WORD(n)] |= AUDIT_BIT(n);
+ }
+ if (class >= AUDIT_SYSCALL_CLASSES || classes[class]) {
+ kfree(p);
+ return -EINVAL;
+ }
+ classes[class] = p;
+ return 0;
+}
+
/* Common user-space to kernel rule translation. */
static inline struct audit_entry *audit_to_entry_common(struct audit_rule *rule)
{
@@ -322,6 +345,22 @@
for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
entry->rule.mask[i] = rule->mask[i];
+ for (i = 0; i < AUDIT_SYSCALL_CLASSES; i++) {
+ int bit = AUDIT_BITMASK_SIZE * 32 - i - 1;
+ __u32 *p = &entry->rule.mask[AUDIT_WORD(bit)];
+ __u32 *class;
+
+ if (!(*p & AUDIT_BIT(bit)))
+ continue;
+ *p &= ~AUDIT_BIT(bit);
+ class = classes[i];
+ if (class) {
+ int j;
+ for (j = 0; j < AUDIT_BITMASK_SIZE; j++)
+ entry->rule.mask[j] |= class[j];
+ }
+ }
+
return entry;
exit_err: