audit: complex interfield comparison helper

Rather than code the same loop over and over implement a helper function which
uses some pointer magic to make it generic enough to be used numerous places
as we implement more audit interfield comparisons

Signed-off-by: Eric Paris <eparis@redhat.com>
This commit is contained in:
Eric Paris 2012-01-03 14:23:08 -05:00 committed by Al Viro
parent 02d86a568c
commit b34b039324

View File

@ -463,25 +463,53 @@ static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
return 0;
}
static int audit_compare_id(uid_t uid1,
struct audit_names *name,
unsigned long name_offset,
struct audit_field *f,
struct audit_context *ctx)
{
struct audit_names *n;
unsigned long addr;
uid_t uid2;
int rc;
if (name) {
addr = (unsigned long)name;
addr += name_offset;
uid2 = *(uid_t *)addr;
rc = audit_comparator(uid1, f->op, uid2);
if (rc)
return rc;
}
if (ctx) {
list_for_each_entry(n, &ctx->names_list, list) {
addr = (unsigned long)n;
addr += name_offset;
uid2 = *(uid_t *)addr;
rc = audit_comparator(uid1, f->op, uid2);
if (rc)
return rc;
}
}
return 0;
}
static int audit_field_compare(struct task_struct *tsk,
const struct cred *cred,
struct audit_field *f,
struct audit_context *ctx,
struct audit_names *name)
{
struct audit_names *n;
switch (f->val) {
case AUDIT_COMPARE_UID_TO_OBJ_UID:
if (name) {
return audit_comparator(cred->uid, f->op, name->uid);
} else if (ctx) {
list_for_each_entry(n, &ctx->names_list, list) {
if (audit_comparator(cred->uid, f->op, n->uid))
return 1;
}
}
break;
return audit_compare_id(cred->uid,
name, offsetof(struct audit_names, uid),
f, ctx);
default:
WARN(1, "Missing AUDIT_COMPARE define. Report as a bug\n");
return 0;