[NET]: Supporting UDP-Lite (RFC 3828) in Linux
This is a revision of the previously submitted patch, which alters
the way files are organized and compiled in the following manner:
* UDP and UDP-Lite now use separate object files
* source file dependencies resolved via header files
net/ipv{4,6}/udp_impl.h
* order of inclusion files in udp.c/udplite.c adapted
accordingly
[NET/IPv4]: Support for the UDP-Lite protocol (RFC 3828)
This patch adds support for UDP-Lite to the IPv4 stack, provided as an
extension to the existing UDPv4 code:
* generic routines are all located in net/ipv4/udp.c
* UDP-Lite specific routines are in net/ipv4/udplite.c
* MIB/statistics support in /proc/net/snmp and /proc/net/udplite
* shared API with extensions for partial checksum coverage
[NET/IPv6]: Extension for UDP-Lite over IPv6
It extends the existing UDPv6 code base with support for UDP-Lite
in the same manner as per UDPv4. In particular,
* UDPv6 generic and shared code is in net/ipv6/udp.c
* UDP-Litev6 specific extensions are in net/ipv6/udplite.c
* MIB/statistics support in /proc/net/snmp6 and /proc/net/udplite6
* support for IPV6_ADDRFORM
* aligned the coding style of protocol initialisation with af_inet6.c
* made the error handling in udpv6_queue_rcv_skb consistent;
to return `-1' on error on all error cases
* consolidation of shared code
[NET]: UDP-Lite Documentation and basic XFRM/Netfilter support
The UDP-Lite patch further provides
* API documentation for UDP-Lite
* basic xfrm support
* basic netfilter support for IPv4 and IPv6 (LOG target)
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/udp.h b/include/net/udp.h
index db0c05f..4f06267 100644
--- a/include/net/udp.h
+++ b/include/net/udp.h
@@ -26,9 +26,28 @@
#include <net/inet_sock.h>
#include <net/sock.h>
#include <net/snmp.h>
+#include <net/ip.h>
+#include <linux/ipv6.h>
#include <linux/seq_file.h>
-#define UDP_HTABLE_SIZE 128
+/**
+ * struct udp_skb_cb - UDP(-Lite) private variables
+ *
+ * @header: private variables used by IPv4/IPv6
+ * @cscov: checksum coverage length (UDP-Lite only)
+ * @partial_cov: if set indicates partial csum coverage
+ */
+struct udp_skb_cb {
+ union {
+ struct inet_skb_parm h4;
+#if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
+ struct inet6_skb_parm h6;
+#endif
+ } header;
+ __u16 cscov;
+ __u8 partial_cov;
+};
+#define UDP_SKB_CB(__skb) ((struct udp_skb_cb *)((__skb)->cb))
extern struct hlist_head udp_hash[UDP_HTABLE_SIZE];
extern rwlock_t udp_hash_lock;
@@ -47,6 +66,62 @@
struct sk_buff;
+/*
+ * Generic checksumming routines for UDP(-Lite) v4 and v6
+ */
+static inline u16 __udp_lib_checksum_complete(struct sk_buff *skb)
+{
+ if (! UDP_SKB_CB(skb)->partial_cov)
+ return __skb_checksum_complete(skb);
+ return csum_fold(skb_checksum(skb, 0, UDP_SKB_CB(skb)->cscov,
+ skb->csum));
+}
+
+static __inline__ int udp_lib_checksum_complete(struct sk_buff *skb)
+{
+ return skb->ip_summed != CHECKSUM_UNNECESSARY &&
+ __udp_lib_checksum_complete(skb);
+}
+
+/**
+ * udp_csum_outgoing - compute UDPv4/v6 checksum over fragments
+ * @sk: socket we are writing to
+ * @skb: sk_buff containing the filled-in UDP header
+ * (checksum field must be zeroed out)
+ */
+static inline u32 udp_csum_outgoing(struct sock *sk, struct sk_buff *skb)
+{
+ u32 csum = csum_partial(skb->h.raw, sizeof(struct udphdr), 0);
+
+ skb_queue_walk(&sk->sk_write_queue, skb) {
+ csum = csum_add(csum, skb->csum);
+ }
+ return csum;
+}
+
+/* hash routines shared between UDPv4/6 and UDP-Litev4/6 */
+static inline void udp_lib_hash(struct sock *sk)
+{
+ BUG();
+}
+
+static inline void udp_lib_unhash(struct sock *sk)
+{
+ write_lock_bh(&udp_hash_lock);
+ if (sk_del_node_init(sk)) {
+ inet_sk(sk)->num = 0;
+ sock_prot_dec_use(sk->sk_prot);
+ }
+ write_unlock_bh(&udp_hash_lock);
+}
+
+static inline void udp_lib_close(struct sock *sk, long timeout)
+{
+ sk_common_release(sk);
+}
+
+
+/* net/ipv4/udp.c */
extern int udp_get_port(struct sock *sk, unsigned short snum,
int (*saddr_cmp)(const struct sock *, const struct sock *));
extern void udp_err(struct sk_buff *, u32);
@@ -61,21 +136,29 @@
poll_table *wait);
DECLARE_SNMP_STAT(struct udp_mib, udp_statistics);
-#define UDP_INC_STATS(field) SNMP_INC_STATS(udp_statistics, field)
-#define UDP_INC_STATS_BH(field) SNMP_INC_STATS_BH(udp_statistics, field)
-#define UDP_INC_STATS_USER(field) SNMP_INC_STATS_USER(udp_statistics, field)
+/*
+ * SNMP statistics for UDP and UDP-Lite
+ */
+#define UDP_INC_STATS_USER(field, is_udplite) do { \
+ if (is_udplite) SNMP_INC_STATS_USER(udplite_statistics, field); \
+ else SNMP_INC_STATS_USER(udp_statistics, field); } while(0)
+#define UDP_INC_STATS_BH(field, is_udplite) do { \
+ if (is_udplite) SNMP_INC_STATS_BH(udplite_statistics, field); \
+ else SNMP_INC_STATS_BH(udp_statistics, field); } while(0)
/* /proc */
struct udp_seq_afinfo {
struct module *owner;
char *name;
sa_family_t family;
+ struct hlist_head *hashtable;
int (*seq_show) (struct seq_file *m, void *v);
struct file_operations *seq_fops;
};
struct udp_iter_state {
sa_family_t family;
+ struct hlist_head *hashtable;
int bucket;
struct seq_operations seq_ops;
};