X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Flinux%2Fnetfilter%2Fnf_conntrack_proto_gre.h;fp=include%2Flinux%2Fnetfilter%2Fnf_conntrack_proto_gre.h;h=4e6bbce04ff85eed993a6b007d6c82ae05e8c74a;hb=76828883507a47dae78837ab5dec5a5b4513c667;hp=0000000000000000000000000000000000000000;hpb=64ba3f394c830ec48a1c31b53dcae312c56f1604;p=linux-2.6.git diff --git a/include/linux/netfilter/nf_conntrack_proto_gre.h b/include/linux/netfilter/nf_conntrack_proto_gre.h new file mode 100644 index 000000000..4e6bbce04 --- /dev/null +++ b/include/linux/netfilter/nf_conntrack_proto_gre.h @@ -0,0 +1,112 @@ +#ifndef _CONNTRACK_PROTO_GRE_H +#define _CONNTRACK_PROTO_GRE_H +#include + +/* 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 defines" +#endif + __be16 protocol; +}; + +/* modified GRE header for PPTP */ +struct gre_hdr_pptp { + __u8 flags; /* bitfield */ + __u8 version; /* should be GRE_VERSION_PPTP */ + __be16 protocol; /* should be GRE_PROTOCOL_PPTP */ + __be16 payload_len; /* size of ppp payload, not inc. gre header */ + __be16 call_id; /* peer's call_id for this session */ + __be32 seq; /* sequence number. Present if S==1 */ + __be32 ack; /* seq number of highest packet recieved by */ + /* sender in this session */ +}; + +struct nf_ct_gre { + unsigned int stream_timeout; + unsigned int timeout; +}; + +#ifdef __KERNEL__ +#include + +struct nf_conn; + +/* structure for original <-> reply keymap */ +struct nf_ct_gre_keymap { + struct list_head list; + struct nf_conntrack_tuple tuple; +}; + +/* add new tuple->key_reply pair to keymap */ +int nf_ct_gre_keymap_add(struct nf_conn *ct, enum ip_conntrack_dir dir, + struct nf_conntrack_tuple *t); + +/* delete keymap entries */ +void nf_ct_gre_keymap_destroy(struct nf_conn *ct); + +/* get pointer to gre key, if present */ +static inline __be32 *gre_key(struct gre_hdr *greh) +{ + if (!greh->key) + return NULL; + if (greh->csum || greh->routing) + return (__be32 *)(greh+sizeof(*greh)+4); + return (__be32 *)(greh+sizeof(*greh)); +} + +/* get pointer ot gre csum, if present */ +static inline __sum16 *gre_csum(struct gre_hdr *greh) +{ + if (!greh->csum) + return NULL; + return (__sum16 *)(greh+sizeof(*greh)); +} + +extern void nf_ct_gre_keymap_flush(void); +extern void nf_nat_need_gre(void); + +#endif /* __KERNEL__ */ +#endif /* _CONNTRACK_PROTO_GRE_H */