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Diffstat (limited to 'net/ipv4/udp.c')
-rw-r--r--net/ipv4/udp.c96
1 files changed, 60 insertions, 36 deletions
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 514c1e9ae81..7552b50bcd8 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -118,14 +118,34 @@ DEFINE_SNMP_STAT(struct udp_mib, udp_statistics) __read_mostly;
struct hlist_head udp_hash[UDP_HTABLE_SIZE];
DEFINE_RWLOCK(udp_hash_lock);
-/* Shared by v4/v6 udp. */
+/* Shared by v4/v6 udp_get_port */
int udp_port_rover;
-static int udp_v4_get_port(struct sock *sk, unsigned short snum)
+static inline int udp_lport_inuse(u16 num)
{
+ struct sock *sk;
struct hlist_node *node;
+
+ sk_for_each(sk, node, &udp_hash[num & (UDP_HTABLE_SIZE - 1)])
+ if (inet_sk(sk)->num == num)
+ return 1;
+ return 0;
+}
+
+/**
+ * udp_get_port - common port lookup for IPv4 and IPv6
+ *
+ * @sk: socket struct in question
+ * @snum: port number to look up
+ * @saddr_comp: AF-dependent comparison of bound local IP addresses
+ */
+int udp_get_port(struct sock *sk, unsigned short snum,
+ int (*saddr_cmp)(struct sock *sk1, struct sock *sk2))
+{
+ struct hlist_node *node;
+ struct hlist_head *head;
struct sock *sk2;
- struct inet_sock *inet = inet_sk(sk);
+ int error = 1;
write_lock_bh(&udp_hash_lock);
if (snum == 0) {
@@ -137,11 +157,10 @@ static int udp_v4_get_port(struct sock *sk, unsigned short snum)
best_size_so_far = 32767;
best = result = udp_port_rover;
for (i = 0; i < UDP_HTABLE_SIZE; i++, result++) {
- struct hlist_head *list;
int size;
- list = &udp_hash[result & (UDP_HTABLE_SIZE - 1)];
- if (hlist_empty(list)) {
+ head = &udp_hash[result & (UDP_HTABLE_SIZE - 1)];
+ if (hlist_empty(head)) {
if (result > sysctl_local_port_range[1])
result = sysctl_local_port_range[0] +
((result - sysctl_local_port_range[0]) &
@@ -149,12 +168,11 @@ static int udp_v4_get_port(struct sock *sk, unsigned short snum)
goto gotit;
}
size = 0;
- sk_for_each(sk2, node, list)
- if (++size >= best_size_so_far)
- goto next;
- best_size_so_far = size;
- best = result;
- next:;
+ sk_for_each(sk2, node, head)
+ if (++size < best_size_so_far) {
+ best_size_so_far = size;
+ best = result;
+ }
}
result = best;
for(i = 0; i < (1 << 16) / UDP_HTABLE_SIZE; i++, result += UDP_HTABLE_SIZE) {
@@ -170,38 +188,44 @@ static int udp_v4_get_port(struct sock *sk, unsigned short snum)
gotit:
udp_port_rover = snum = result;
} else {
- sk_for_each(sk2, node,
- &udp_hash[snum & (UDP_HTABLE_SIZE - 1)]) {
- struct inet_sock *inet2 = inet_sk(sk2);
-
- if (inet2->num == snum &&
- sk2 != sk &&
- !ipv6_only_sock(sk2) &&
- (!sk2->sk_bound_dev_if ||
- !sk->sk_bound_dev_if ||
- sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
- (!inet2->rcv_saddr ||
- !inet->rcv_saddr ||
- inet2->rcv_saddr == inet->rcv_saddr) &&
- (!sk2->sk_reuse || !sk->sk_reuse))
+ head = &udp_hash[snum & (UDP_HTABLE_SIZE - 1)];
+
+ sk_for_each(sk2, node, head)
+ if (inet_sk(sk2)->num == snum &&
+ sk2 != sk &&
+ (!sk2->sk_reuse || !sk->sk_reuse) &&
+ (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if
+ || sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
+ (*saddr_cmp)(sk, sk2) )
goto fail;
- }
}
- inet->num = snum;
+ inet_sk(sk)->num = snum;
if (sk_unhashed(sk)) {
- struct hlist_head *h = &udp_hash[snum & (UDP_HTABLE_SIZE - 1)];
-
- sk_add_node(sk, h);
+ head = &udp_hash[snum & (UDP_HTABLE_SIZE - 1)];
+ sk_add_node(sk, head);
sock_prot_inc_use(sk->sk_prot);
}
- write_unlock_bh(&udp_hash_lock);
- return 0;
-
+ error = 0;
fail:
write_unlock_bh(&udp_hash_lock);
- return 1;
+ return error;
+}
+
+static inline int ipv4_rcv_saddr_equal(struct sock *sk1, struct sock *sk2)
+{
+ struct inet_sock *inet1 = inet_sk(sk1), *inet2 = inet_sk(sk2);
+
+ return ( !ipv6_only_sock(sk2) &&
+ (!inet1->rcv_saddr || !inet2->rcv_saddr ||
+ inet1->rcv_saddr == inet2->rcv_saddr ));
+}
+
+static inline int udp_v4_get_port(struct sock *sk, unsigned short snum)
+{
+ return udp_get_port(sk, snum, ipv4_rcv_saddr_equal);
}
+
static void udp_v4_hash(struct sock *sk)
{
BUG();
@@ -1596,7 +1620,7 @@ EXPORT_SYMBOL(udp_disconnect);
EXPORT_SYMBOL(udp_hash);
EXPORT_SYMBOL(udp_hash_lock);
EXPORT_SYMBOL(udp_ioctl);
-EXPORT_SYMBOL(udp_port_rover);
+EXPORT_SYMBOL(udp_get_port);
EXPORT_SYMBOL(udp_prot);
EXPORT_SYMBOL(udp_sendmsg);
EXPORT_SYMBOL(udp_poll);