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#ifndef __NET_UDP_WRAPPER_H
#define __NET_UDP_WRAPPER_H 1
#include <linux/version.h>
#include_next <net/udp.h>
#ifndef HAVE_UDP_FLOW_SRC_PORT
static inline __be16 udp_flow_src_port(struct net *net, struct sk_buff *skb,
int min, int max, bool use_eth)
{
u32 hash;
if (min >= max) {
/* Use default range */
inet_get_local_port_range(net, &min, &max);
}
hash = skb_get_hash(skb);
if (unlikely(!hash) && use_eth) {
/* Can't find a normal hash, caller has indicated an Ethernet
* packet so use that to compute a hash.
*/
hash = jhash(skb->data, 2 * ETH_ALEN,
(__force u32) skb->protocol);
}
/* Since this is being sent on the wire obfuscate hash a bit
* to minimize possbility that any useful information to an
* attacker is leaked. Only upper 16 bits are relevant in the
* computation for 16 bit port value.
*/
hash ^= hash << 16;
return htons((((u64) hash * (max - min)) >> 32) + min);
}
#endif
#if LINUX_VERSION_CODE < KERNEL_VERSION(3,16,0)
static inline __sum16 udp_v4_check(int len, __be32 saddr,
__be32 daddr, __wsum base)
{
return csum_tcpudp_magic(saddr, daddr, len, IPPROTO_UDP, base);
}
void udp_set_csum(bool nocheck, struct sk_buff *skb,
__be32 saddr, __be32 daddr, int len);
#endif
#endif
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