ip_conntrack_proto_gre.h
上传用户:szlgq88
上传日期:2009-04-28
资源大小:48287k
文件大小:2k
源码类别:
嵌入式Linux
开发平台:
Unix_Linux
- #ifndef _CONNTRACK_PROTO_GRE_H
- #define _CONNTRACK_PROTO_GRE_H
- #include <asm/byteorder.h>
- /* GRE PROTOCOL HEADER */
- /* GRE Version field */
- #define GRE_VERSION_1701 0x0
- #define GRE_VERSION_PPTP 0x1
- /* GRE Protocol field */
- #define GRE_PROTOCOL_PPTP 0x880B
- /* GRE Flags */
- #define GRE_FLAG_C 0x80
- #define GRE_FLAG_R 0x40
- #define GRE_FLAG_K 0x20
- #define GRE_FLAG_S 0x10
- #define GRE_FLAG_A 0x80
- #define GRE_IS_C(f) ((f)&GRE_FLAG_C)
- #define GRE_IS_R(f) ((f)&GRE_FLAG_R)
- #define GRE_IS_K(f) ((f)&GRE_FLAG_K)
- #define GRE_IS_S(f) ((f)&GRE_FLAG_S)
- #define GRE_IS_A(f) ((f)&GRE_FLAG_A)
- /* GRE is a mess: Four different standards */
- struct gre_hdr {
- #if defined(__LITTLE_ENDIAN_BITFIELD)
- __u16 rec:3,
- srr:1,
- seq:1,
- key:1,
- routing:1,
- csum:1,
- version:3,
- reserved:4,
- ack:1;
- #elif defined(__BIG_ENDIAN_BITFIELD)
- __u16 csum:1,
- routing:1,
- key:1,
- seq:1,
- srr:1,
- rec:3,
- ack:1,
- reserved:4,
- version:3;
- #else
- #error "Adjust your <asm/byteorder.h> defines"
- #endif
- __u16 protocol;
- };
- /* modified GRE header for PPTP */
- struct gre_hdr_pptp {
- __u8 flags; /* bitfield */
- __u8 version; /* should be GRE_VERSION_PPTP */
- __u16 protocol; /* should be GRE_PROTOCOL_PPTP */
- __u16 payload_len; /* size of ppp payload, not inc. gre header */
- __u16 call_id; /* peer's call_id for this session */
- __u32 seq; /* sequence number. Present if S==1 */
- __u32 ack; /* seq number of highest packet recieved by */
- /* sender in this session */
- };
- /* this is part of ip_conntrack */
- struct ip_ct_gre {
- unsigned int stream_timeout;
- unsigned int timeout;
- };
- #ifdef __KERNEL__
- struct ip_conntrack_expect;
- struct ip_conntrack;
- /* structure for original <-> reply keymap */
- struct ip_ct_gre_keymap {
- struct list_head list;
- struct ip_conntrack_tuple tuple;
- };
- /* add new tuple->key_reply pair to keymap */
- int ip_ct_gre_keymap_add(struct ip_conntrack *ct,
- struct ip_conntrack_tuple *t,
- int reply);
- /* delete keymap entries */
- void ip_ct_gre_keymap_destroy(struct ip_conntrack *ct);
- /* get pointer to gre key, if present */
- static inline u_int32_t *gre_key(struct gre_hdr *greh)
- {
- if (!greh->key)
- return NULL;
- if (greh->csum || greh->routing)
- return (u_int32_t *) (greh+sizeof(*greh)+4);
- return (u_int32_t *) (greh+sizeof(*greh));
- }
- /* get pointer ot gre csum, if present */
- static inline u_int16_t *gre_csum(struct gre_hdr *greh)
- {
- if (!greh->csum)
- return NULL;
- return (u_int16_t *) (greh+sizeof(*greh));
- }
- #endif /* __KERNEL__ */
- #endif /* _CONNTRACK_PROTO_GRE_H */