diff options
Diffstat (limited to 'include/net')
| -rw-r--r-- | include/net/fou.h | 38 | ||||
| -rw-r--r-- | include/net/gue.h | 103 |
2 files changed, 136 insertions, 5 deletions
diff --git a/include/net/fou.h b/include/net/fou.h new file mode 100644 index 000000000000..25b26ffcf1df --- /dev/null +++ b/include/net/fou.h @@ -0,0 +1,38 @@ +#ifndef __NET_FOU_H +#define __NET_FOU_H + +#include <linux/skbuff.h> + +#include <net/flow.h> +#include <net/gue.h> +#include <net/ip_tunnels.h> +#include <net/udp.h> + +int fou_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e, + u8 *protocol, struct flowi4 *fl4); +int gue_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e, + u8 *protocol, struct flowi4 *fl4); + +static size_t fou_encap_hlen(struct ip_tunnel_encap *e) +{ + return sizeof(struct udphdr); +} + +static size_t gue_encap_hlen(struct ip_tunnel_encap *e) +{ + size_t len; + bool need_priv = false; + + len = sizeof(struct udphdr) + sizeof(struct guehdr); + + if (e->flags & TUNNEL_ENCAP_FLAG_REMCSUM) { + len += GUE_PLEN_REMCSUM; + need_priv = true; + } + + len += need_priv ? GUE_LEN_PRIV : 0; + + return len; +} + +#endif diff --git a/include/net/gue.h b/include/net/gue.h index b6c332788084..3f28ec7f1c7f 100644 --- a/include/net/gue.h +++ b/include/net/gue.h @@ -1,23 +1,116 @@ #ifndef __NET_GUE_H #define __NET_GUE_H +/* Definitions for the GUE header, standard and private flags, lengths + * of optional fields are below. + * + * Diagram of GUE header: + * + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * |Ver|C| Hlen | Proto/ctype | Standard flags |P| + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | | + * ~ Fields (optional) ~ + * | | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Private flags (optional, P bit is set) | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | | + * ~ Private fields (optional) ~ + * | | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * + * C bit indicates contol message when set, data message when unset. + * For a control message, proto/ctype is interpreted as a type of + * control message. For data messages, proto/ctype is the IP protocol + * of the next header. + * + * P bit indicates private flags field is present. The private flags + * may refer to options placed after this field. + */ + struct guehdr { union { struct { #if defined(__LITTLE_ENDIAN_BITFIELD) - __u8 hlen:4, - version:4; + __u8 hlen:5, + control:1, + version:2; #elif defined (__BIG_ENDIAN_BITFIELD) - __u8 version:4, - hlen:4; + __u8 version:2, + control:1, + hlen:5; #else #error "Please fix <asm/byteorder.h>" #endif - __u8 next_hdr; + __u8 proto_ctype; __u16 flags; }; __u32 word; }; }; +/* Standard flags in GUE header */ + +#define GUE_FLAG_PRIV htons(1<<0) /* Private flags are in options */ +#define GUE_LEN_PRIV 4 + +#define GUE_FLAGS_ALL (GUE_FLAG_PRIV) + +/* Private flags in the private option extension */ + +#define GUE_PFLAG_REMCSUM htonl(1 << 31) +#define GUE_PLEN_REMCSUM 4 + +#define GUE_PFLAGS_ALL (GUE_PFLAG_REMCSUM) + +/* Functions to compute options length corresponding to flags. + * If we ever have a lot of flags this can be potentially be + * converted to a more optimized algorithm (table lookup + * for instance). + */ +static inline size_t guehdr_flags_len(__be16 flags) +{ + return ((flags & GUE_FLAG_PRIV) ? GUE_LEN_PRIV : 0); +} + +static inline size_t guehdr_priv_flags_len(__be32 flags) +{ + return 0; +} + +/* Validate standard and private flags. Returns non-zero (meaning invalid) + * if there is an unknown standard or private flags, or the options length for + * the flags exceeds the options length specific in hlen of the GUE header. + */ +static inline int validate_gue_flags(struct guehdr *guehdr, + size_t optlen) +{ + size_t len; + __be32 flags = guehdr->flags; + + if (flags & ~GUE_FLAGS_ALL) + return 1; + + len = guehdr_flags_len(flags); + if (len > optlen) + return 1; + + if (flags & GUE_FLAG_PRIV) { + /* Private flags are last four bytes accounted in + * guehdr_flags_len + */ + flags = *(__be32 *)((void *)&guehdr[1] + len - GUE_LEN_PRIV); + + if (flags & ~GUE_PFLAGS_ALL) + return 1; + + len += guehdr_priv_flags_len(flags); + if (len > optlen) + return 1; + } + + return 0; +} + #endif |