inet_diag: Export inet diag cookie checking routine
The netlink diag susbsys stores sk address bits in the nl message
as a "cookie" and uses one when dumps details about particular
socket.
The same will be required for udp diag module, so introduce a heler
in inet_diag module
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/inet_diag.h b/include/linux/inet_diag.h
index 851feff..5036747 100644
--- a/include/linux/inet_diag.h
+++ b/include/linux/inet_diag.h
@@ -144,6 +144,8 @@
__u16 idiag_type;
};
+int inet_diag_check_cookie(struct sock *sk, struct inet_diag_req *req);
+
extern int inet_diag_register(const struct inet_diag_handler *handler);
extern void inet_diag_unregister(const struct inet_diag_handler *handler);
#endif /* __KERNEL__ */
diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
index bd3f661..ba3ae1f 100644
--- a/net/ipv4/inet_diag.c
+++ b/net/ipv4/inet_diag.c
@@ -246,6 +246,18 @@
return inet_csk_diag_fill(sk, skb, r, pid, seq, nlmsg_flags, unlh);
}
+int inet_diag_check_cookie(struct sock *sk, struct inet_diag_req *req)
+{
+ if ((req->id.idiag_cookie[0] != INET_DIAG_NOCOOKIE ||
+ req->id.idiag_cookie[1] != INET_DIAG_NOCOOKIE) &&
+ ((u32)(unsigned long)sk != req->id.idiag_cookie[0] ||
+ (u32)((((unsigned long)sk) >> 31) >> 1) != req->id.idiag_cookie[1]))
+ return -ESTALE;
+ else
+ return 0;
+}
+EXPORT_SYMBOL_GPL(inet_diag_check_cookie);
+
static int inet_diag_get_exact(struct sk_buff *in_skb,
const struct nlmsghdr *nlh,
struct inet_diag_req *req)
@@ -288,11 +300,8 @@
if (sk == NULL)
goto unlock;
- err = -ESTALE;
- if ((req->id.idiag_cookie[0] != INET_DIAG_NOCOOKIE ||
- req->id.idiag_cookie[1] != INET_DIAG_NOCOOKIE) &&
- ((u32)(unsigned long)sk != req->id.idiag_cookie[0] ||
- (u32)((((unsigned long)sk) >> 31) >> 1) != req->id.idiag_cookie[1]))
+ err = inet_diag_check_cookie(sk, req);
+ if (err)
goto out;
err = -ENOMEM;