#ifndef _INET_ECN_H_#define _INET_ECN_H_ #include <linux/ip.h>#include <linux/skbuff.h> #include <net/inet_sock.h>#include <net/dsfield.h> enum { INET_ECN_NOT_ECT = 0, INET_ECN_ECT_1 = 1, INET_ECN_ECT_0 = 2, INET_ECN_CE = 3, INET_ECN_MASK = 3,}; extern int sysctl_tunnel_ecn_log; static inline int INET_ECN_is_ce(__u8 dsfield){ return (dsfield & INET_ECN_MASK) == INET_ECN_CE;} static inline int INET_ECN_is_not_ect(__u8 dsfield){ return (dsfield & INET_ECN_MASK) == INET_ECN_NOT_ECT;} static inline int INET_ECN_is_capable(__u8 dsfield){ return dsfield & INET_ECN_ECT_0;} /* * RFC 3168 9.1.1 * The full-functionality option for ECN encapsulation is to copy the * ECN codepoint of the inside header to the outside header on * encapsulation if the inside header is not-ECT or ECT, and to set the * ECN codepoint of the outside header to ECT(0) if the ECN codepoint of * the inside header is CE. */static inline __u8 INET_ECN_encapsulate(__u8 outer, __u8 inner){ outer &= ~INET_ECN_MASK; outer |= !INET_ECN_is_ce(inner) ? (inner & INET_ECN_MASK) : INET_ECN_ECT_0; return outer;} static inline void INET_ECN_xmit(struct sock *sk){ inet_sk(sk)->tos |= INET_ECN_ECT_0; if (inet6_sk(sk) != NULL) inet6_sk(sk)->tclass |= INET_ECN_ECT_0;} static inline void INET_ECN_dontxmit(struct sock *sk){ inet_sk(sk)->tos &= ~INET_ECN_MASK; if (inet6_sk(sk) != NULL) inet6_sk(sk)->tclass &= ~INET_ECN_MASK;} #define IP6_ECN_flow_init(label) do { \ (label) &= ~htonl(INET_ECN_MASK << 20); \ } while (0) #define IP6_ECN_flow_xmit(sk, label) do { \ if (INET_ECN_is_capable(inet6_sk(sk)->tclass)) \ (label) |= htonl(INET_ECN_ECT_0 << 20); \ } while (0) static inline int IP_ECN_set_ce(struct iphdr *iph){ u32 check = (__force u32)iph->check; u32 ecn = (iph->tos + 1) & INET_ECN_MASK; /* * After the last operation we have (in binary): * INET_ECN_NOT_ECT => 01 * INET_ECN_ECT_1 => 10 * INET_ECN_ECT_0 => 11 * INET_ECN_CE => 00 */ if (!(ecn & 2)) return !ecn; /* * The following gives us: * INET_ECN_ECT_1 => check += htons(0xFFFD) * INET_ECN_ECT_0 => check += htons(0xFFFE) */ check += (__force u16)htons(0xFFFB) + (__force u16)htons(ecn); iph->check = (__force __sum16)(check + (check>=0xFFFF)); iph->tos |= INET_ECN_CE; return 1;} static inline void IP_ECN_clear(struct iphdr *iph){ iph->tos &= ~INET_ECN_MASK;} static inline void ipv4_copy_dscp(unsigned int dscp, struct iphdr *inner){ dscp &= ~INET_ECN_MASK; ipv4_change_dsfield(inner, INET_ECN_MASK, dscp);} struct ipv6hdr; static inline int IP6_ECN_set_ce(struct ipv6hdr *iph){ if (INET_ECN_is_not_ect(ipv6_get_dsfield(iph))) return 0; *(__be32*)iph |= htonl(INET_ECN_CE << 20); return 1;} static inline void IP6_ECN_clear(struct ipv6hdr *iph){ *(__be32*)iph &= ~htonl(INET_ECN_MASK << 20);} static inline void ipv6_copy_dscp(unsigned int dscp, struct ipv6hdr *inner){ dscp &= ~INET_ECN_MASK; ipv6_change_dsfield(inner, INET_ECN_MASK, dscp);} static inline int INET_ECN_set_ce(struct sk_buff *skb){ switch (skb->protocol) { case cpu_to_be16(ETH_P_IP): if (skb_network_header(skb) + sizeof(struct iphdr) <= skb_tail_pointer(skb)) return IP_ECN_set_ce(ip_hdr(skb)); break; case cpu_to_be16(ETH_P_IPV6): if (skb_network_header(skb) + sizeof(struct ipv6hdr) <= skb_tail_pointer(skb)) return IP6_ECN_set_ce(ipv6_hdr(skb)); break; } return 0;} /* * RFC 6080 4.2 * To decapsulate the inner header at the tunnel egress, a compliant * tunnel egress MUST set the outgoing ECN field to the codepoint at the * intersection of the appropriate arriving inner header (row) and outer * header (column) in Figure 4 * * +---------+------------------------------------------------+ * |Arriving | Arriving Outer Header | * | Inner +---------+------------+------------+------------+ * | Header | Not-ECT | ECT(0) | ECT(1) | CE | * +---------+---------+------------+------------+------------+ * | Not-ECT | Not-ECT |Not-ECT(!!!)|Not-ECT(!!!)| <drop>(!!!)| * | ECT(0) | ECT(0) | ECT(0) | ECT(1) | CE | * | ECT(1) | ECT(1) | ECT(1) (!) | ECT(1) | CE | * | CE | CE | CE | CE(!!!)| CE | * +---------+---------+------------+------------+------------+ * * Figure 4: New IP in IP Decapsulation Behaviour * * returns 0 on success * 1 if something is broken and should be logged (!!! above) * 2 if packet should be dropped */static inline int INET_ECN_decapsulate(struct sk_buff *skb, __u8 outer, __u8 inner){ if (INET_ECN_is_not_ect(inner)) { switch (outer & INET_ECN_MASK) { case INET_ECN_NOT_ECT: return 0; case INET_ECN_ECT_0: case INET_ECN_ECT_1: return 1; case INET_ECN_CE: return 2; } } if (INET_ECN_is_ce(outer)) INET_ECN_set_ce(skb); return 0;} static inline int IP_ECN_decapsulate(const struct iphdr *oiph, struct sk_buff *skb){ __u8 inner; if (skb->protocol == htons(ETH_P_IP)) inner = ip_hdr(skb)->tos; else if (skb->protocol == htons(ETH_P_IPV6)) inner = ipv6_get_dsfield(ipv6_hdr(skb)); else return 0; return INET_ECN_decapsulate(skb, oiph->tos, inner);} static inline int IP6_ECN_decapsulate(const struct ipv6hdr *oipv6h, struct sk_buff *skb){ __u8 inner; if (skb->protocol == htons(ETH_P_IP)) inner = ip_hdr(skb)->tos; else if (skb->protocol == htons(ETH_P_IPV6)) inner = ipv6_get_dsfield(ipv6_hdr(skb)); else return 0; return INET_ECN_decapsulate(skb, ipv6_get_dsfield(oipv6h), inner);}#endif
#ifndef _INET_ECN_H_
#define _INET_ECN_H_
#include <linux/ip.h>
#include <linux/skbuff.h>
#include <net/inet_sock.h>
#include <net/dsfield.h>
enum {
INET_ECN_NOT_ECT = 0,
INET_ECN_ECT_1 = 1,
INET_ECN_ECT_0 = 2,
INET_ECN_CE = 3,
INET_ECN_MASK = 3,
};
extern int sysctl_tunnel_ecn_log;
static inline int INET_ECN_is_ce(__u8 dsfield)
{
return (dsfield & INET_ECN_MASK) == INET_ECN_CE;
}
static inline int INET_ECN_is_not_ect(__u8 dsfield)
{
return (dsfield & INET_ECN_MASK) == INET_ECN_NOT_ECT;
}
static inline int INET_ECN_is_capable(__u8 dsfield)
{
return dsfield & INET_ECN_ECT_0;
}
/*
* RFC 3168 9.1.1
* The full-functionality option for ECN encapsulation is to copy the
* ECN codepoint of the inside header to the outside header on
* encapsulation if the inside header is not-ECT or ECT, and to set the
* ECN codepoint of the outside header to ECT(0) if the ECN codepoint of
* the inside header is CE.
*/
static inline __u8 INET_ECN_encapsulate(__u8 outer, __u8 inner)
{
outer &= ~INET_ECN_MASK;
outer |= !INET_ECN_is_ce(inner) ? (inner & INET_ECN_MASK) :
INET_ECN_ECT_0;
return outer;
}
static inline void INET_ECN_xmit(struct sock *sk)
{
inet_sk(sk)->tos |= INET_ECN_ECT_0;
if (inet6_sk(sk) != NULL)
inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
}
static inline void INET_ECN_dontxmit(struct sock *sk)
{
inet_sk(sk)->tos &= ~INET_ECN_MASK;
if (inet6_sk(sk) != NULL)
inet6_sk(sk)->tclass &= ~INET_ECN_MASK;
}
#define IP6_ECN_flow_init(label) do { \
(label) &= ~htonl(INET_ECN_MASK << 20); \
} while (0)
#define IP6_ECN_flow_xmit(sk, label) do { \
if (INET_ECN_is_capable(inet6_sk(sk)->tclass)) \
(label) |= htonl(INET_ECN_ECT_0 << 20); \
} while (0)
static inline int IP_ECN_set_ce(struct iphdr *iph)
{
u32 check = (__force u32)iph->check;
u32 ecn = (iph->tos + 1) & INET_ECN_MASK;
/*
* After the last operation we have (in binary):
* INET_ECN_NOT_ECT => 01
* INET_ECN_ECT_1 => 10
* INET_ECN_ECT_0 => 11
* INET_ECN_CE => 00
*/
if (!(ecn & 2))
return !ecn;
/*
* The following gives us:
* INET_ECN_ECT_1 => check += htons(0xFFFD)
* INET_ECN_ECT_0 => check += htons(0xFFFE)
*/
check += (__force u16)htons(0xFFFB) + (__force u16)htons(ecn);
iph->check = (__force __sum16)(check + (check>=0xFFFF));
iph->tos |= INET_ECN_CE;
return 1;
}
static inline void IP_ECN_clear(struct iphdr *iph)
{
iph->tos &= ~INET_ECN_MASK;
}
static inline void ipv4_copy_dscp(unsigned int dscp, struct iphdr *inner)
{
dscp &= ~INET_ECN_MASK;
ipv4_change_dsfield(inner, INET_ECN_MASK, dscp);
}
struct ipv6hdr;
static inline int IP6_ECN_set_ce(struct ipv6hdr *iph)
{
if (INET_ECN_is_not_ect(ipv6_get_dsfield(iph)))
return 0;
*(__be32*)iph |= htonl(INET_ECN_CE << 20);
return 1;
}
static inline void IP6_ECN_clear(struct ipv6hdr *iph)
{
*(__be32*)iph &= ~htonl(INET_ECN_MASK << 20);
}
static inline void ipv6_copy_dscp(unsigned int dscp, struct ipv6hdr *inner)
{
dscp &= ~INET_ECN_MASK;
ipv6_change_dsfield(inner, INET_ECN_MASK, dscp);
}
static inline int INET_ECN_set_ce(struct sk_buff *skb)
{
switch (skb->protocol) {
case cpu_to_be16(ETH_P_IP):
if (skb_network_header(skb) + sizeof(struct iphdr) <=
skb_tail_pointer(skb))
return IP_ECN_set_ce(ip_hdr(skb));
break;
case cpu_to_be16(ETH_P_IPV6):
if (skb_network_header(skb) + sizeof(struct ipv6hdr) <=
skb_tail_pointer(skb))
return IP6_ECN_set_ce(ipv6_hdr(skb));
break;
}
return 0;
}
/*
* RFC 6080 4.2
* To decapsulate the inner header at the tunnel egress, a compliant
* tunnel egress MUST set the outgoing ECN field to the codepoint at the
* intersection of the appropriate arriving inner header (row) and outer
* header (column) in Figure 4
*
* +---------+------------------------------------------------+
* |Arriving | Arriving Outer Header |
* | Inner +---------+------------+------------+------------+
* | Header | Not-ECT | ECT(0) | ECT(1) | CE |
* +---------+---------+------------+------------+------------+
* | Not-ECT | Not-ECT |Not-ECT(!!!)|Not-ECT(!!!)| <drop>(!!!)|
* | ECT(0) | ECT(0) | ECT(0) | ECT(1) | CE |
* | ECT(1) | ECT(1) | ECT(1) (!) | ECT(1) | CE |
* | CE | CE | CE | CE(!!!)| CE |
* +---------+---------+------------+------------+------------+
*
* Figure 4: New IP in IP Decapsulation Behaviour
*
* returns 0 on success
* 1 if something is broken and should be logged (!!! above)
* 2 if packet should be dropped
*/
static inline int INET_ECN_decapsulate(struct sk_buff *skb,
__u8 outer, __u8 inner)
{
if (INET_ECN_is_not_ect(inner)) {
switch (outer & INET_ECN_MASK) {
case INET_ECN_NOT_ECT:
return 0;
case INET_ECN_ECT_0:
case INET_ECN_ECT_1:
return 1;
case INET_ECN_CE:
return 2;
}
}
if (INET_ECN_is_ce(outer))
INET_ECN_set_ce(skb);
return 0;
}
static inline int IP_ECN_decapsulate(const struct iphdr *oiph,
struct sk_buff *skb)
{
__u8 inner;
if (skb->protocol == htons(ETH_P_IP))
inner = ip_hdr(skb)->tos;
else if (skb->protocol == htons(ETH_P_IPV6))
inner = ipv6_get_dsfield(ipv6_hdr(skb));
else
return 0;
return INET_ECN_decapsulate(skb, oiph->tos, inner);
}
static inline int IP6_ECN_decapsulate(const struct ipv6hdr *oipv6h,
struct sk_buff *skb)
{
__u8 inner;
if (skb->protocol == htons(ETH_P_IP))
inner = ip_hdr(skb)->tos;
else if (skb->protocol == htons(ETH_P_IPV6))
inner = ipv6_get_dsfield(ipv6_hdr(skb));
else
return 0;
return INET_ECN_decapsulate(skb, ipv6_get_dsfield(oipv6h), inner);
}
#endif