net: add real socket cookies

[karo-tx-linux.git] / net / core / sock_diag.c

diff --git a/net/core/sock_diag.c b/net/core/sock_diag.c
index 96e70ee05a8dde068622a59e9db850f44110980c..74dddf84adcdd7fea05ca93d94f97c6558917ae1 100644 (file)
--- a/net/core/sock_diag.c
+++ b/net/core/sock_diag.c
@@ -13,22 +13,39 @@ static const struct sock_diag_handler *sock_diag_handlers[AF_MAX];
 static int (*inet_rcv_compat)(struct sk_buff *skb, struct nlmsghdr *nlh);
 static DEFINE_MUTEX(sock_diag_table_mutex);
 
-int sock_diag_check_cookie(void *sk, const __u32 *cookie)
+static u64 sock_gen_cookie(struct sock *sk)
 {
-       if ((cookie[0] != INET_DIAG_NOCOOKIE ||
-            cookie[1] != INET_DIAG_NOCOOKIE) &&
-           ((u32)(unsigned long)sk != cookie[0] ||
-            (u32)((((unsigned long)sk) >> 31) >> 1) != cookie[1]))
-               return -ESTALE;
-       else
+       while (1) {
+               u64 res = atomic64_read(&sk->sk_cookie);
+
+               if (res)
+                       return res;
+               res = atomic64_inc_return(&sock_net(sk)->cookie_gen);
+               atomic64_cmpxchg(&sk->sk_cookie, 0, res);
+       }
+}
+
+int sock_diag_check_cookie(struct sock *sk, const __u32 *cookie)
+{
+       u64 res;
+
+       if (cookie[0] == INET_DIAG_NOCOOKIE && cookie[1] == INET_DIAG_NOCOOKIE)
                return 0;
+
+       res = sock_gen_cookie(sk);
+       if ((u32)res != cookie[0] || (u32)(res >> 32) != cookie[1])
+               return -ESTALE;
+
+       return 0;
 }
 EXPORT_SYMBOL_GPL(sock_diag_check_cookie);
 
-void sock_diag_save_cookie(void *sk, __u32 *cookie)
+void sock_diag_save_cookie(struct sock *sk, __u32 *cookie)
 {
-       cookie[0] = (u32)(unsigned long)sk;
-       cookie[1] = (u32)(((unsigned long)sk >> 31) >> 1);
+       u64 res = sock_gen_cookie(sk);
+
+       cookie[0] = (u32)res;
+       cookie[1] = (u32)(res >> 32);
 }
 EXPORT_SYMBOL_GPL(sock_diag_save_cookie);