suricata/src/decode-ipv6.h

/* Copyright (c) 2008 Victor Julien <victor@inliniac.net> */

#ifndef __DECODE_IPV6_H__
#define __DECODE_IPV6_H__

#include <sys/types.h>
#include <pcap.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <net/if.h>

#define IPV6_HEADER_LEN            40
#define	IPV6_MAXPACKET	           65535 /* maximum packet size */
#define IPV6_MAX_OPT               40

typedef struct _IPV6Hdr
{
    union {
        struct _ip6_un1 {
            u_int32_t ip6_un1_flow; /* 20 bits of flow-ID */
            u_int16_t ip6_un1_plen; /* payload length */
            u_int8_t  ip6_un1_nxt;  /* next header */
            u_int8_t  ip6_un1_hlim; /* hop limit */
        } ip6_un1;
        u_int8_t ip6_un2_vfc;   /* 4 bits version, top 4 bits class */
    } ip6_hdrun;

    u_int32_t ip6_src[4];
    u_int32_t ip6_dst[4];
} IPV6Hdr;

#define s_ip6_vfc     ip6_hdrun.ip6_un2_vfc
#define s_ip6_flow    ip6_hdrun.ip6_un1.ip6_un1_flow
#define s_ip6_plen    ip6_hdrun.ip6_un1.ip6_un1_plen
#define s_ip6_nxt     ip6_hdrun.ip6_un1.ip6_un1_nxt
#define s_ip6_hlim    ip6_hdrun.ip6_un1.ip6_un1_hlim

#define IPV6_GET_RAW_VER(ip6h)            (((ip6h)->s_ip6_vfc & 0xf0) >> 4)
#define IPV6_GET_RAW_CLASS(ip6h)          ((ntohl((ip6h)->s_ip6_flow) & 0x0FF00000) >> 20)
#define IPV6_GET_RAW_FLOW(ip6h)           (ntohl((ip6h)->s_ip6_flow) & 0x000FFFFF)
#define IPV6_GET_RAW_NH(ip6h)             ((ip6h)->s_ip6_nxt)
#define IPV6_GET_RAW_PLEN(ip6h)           (ntohs((ip6h)->s_ip6_plen))
#define IPV6_GET_RAW_HLIM(ip6h)           ((ip6h)->s_ip6_hlim)

#define IPV6_SET_RAW_VER(ip6h, value)     ((ip6h)->s_ip6_vfc = (((ip6h)->s_ip6_vfc & 0x0f) | (value << 4)))

#define IPV6_SET_L4PROTO(p,proto)         (p)->ip6vars.l4proto = proto

/* this is enough since noone will access the cache without first
 * checking the flags */
#define IPV6_CACHE_INIT(p)                (p)->ip6c.flags = 0

/* ONLY call these functions after making sure that:
 * 1. p->ip6h is set
 * 2. p->ip6h is valid (len is correct)
 * 3. cache is initialized
 */
#define IPV6_GET_VER(p) \
    ((p)->ip6c.flags & IPV6_CACHE_VER ? \
    (p)->ip6c.ver : ((p)->ip6c.flags |= IPV6_CACHE_VER, (p)->ip6c.ver = IPV6_GET_RAW_VER((p)->ip6h)))
#define IPV6_GET_CLASS(p) \
    ((p)->ip6c.flags & IPV6_CACHE_CLASS ? \
    (p)->ip6c.cl : ((p)->ip6c.flags |= IPV6_CACHE_CLASS, (p)->ip6c.cl = IPV6_GET_RAW_CLASS((p)->ip6h)))
#define IPV6_GET_FLOW(p) \
    (p)->ip6c.flags & IPV6_CACHE_FLOW ? \
    (p)->ip6c.flow : ((p)->ip6c.flags |= IPV6_CACHE_FLOW, (p)->ip6c.flow = IPV6_GET_RAW_FLOW((p)->ip6h))
#define IPV6_GET_NH(p) \
    IPV6_GET_RAW_NH((p)->ip6h)
#define IPV6_GET_PLEN(p) \
    (p)->ip6c.flags & IPV6_CACHE_PLEN ? \
    (p)->ip6c.plen : ((p)->ip6c.flags |= IPV6_CACHE_PLEN, (p)->ip6c.plen = IPV6_GET_RAW_PLEN((p)->ip6h))
#define IPV6_GET_HLIM(p) \
    IPV6_GET_RAW_HLIM((p)->ip6h)
/* XXX */
#define IPV6_GET_L4PROTO(p) \
    (p)->ip6vars.l4proto

#define IPV6_CACHE_VER                    0x0001 /* 1 */
#define IPV6_CACHE_CLASS                  0x0002 /* 2 */
#define IPV6_CACHE_FLOW                   0x0004 /* 4 */
#define IPV6_CACHE_NH                     0x0008 /* 8 */
#define IPV6_CACHE_PLEN                   0x0010 /* 16 */
#define IPV6_CACHE_HLIM                   0x0020 /* 32 */

/* decoder cache */
typedef struct _IPV6Cache
{
    u_int16_t flags;
    u_int8_t ver;
    u_int8_t cl;
    u_int8_t flow;
    u_int8_t nh;
    u_int16_t plen;
    u_int8_t hlim;
} IPV6Cache;

/* helper structure with parsed ipv6 info */
typedef struct _IPV6Vars
{
    u_int8_t ip_opts_len;
    u_int8_t l4proto;      /* the proto after the extension headers
                            * store while decoding so we don't have
                            * to loop through the exthdrs all the time */
} IPV6Vars;

/* Fragment header */
typedef struct _IPV6FragHdr
{
    u_int8_t  ip6fh_nxt;             /* next header */
    u_int8_t  ip6fh_reserved;        /* reserved field */
    u_int16_t ip6fh_offlg;           /* offset, reserved, and flag */
    u_int32_t ip6fh_ident;           /* identification */
} IPV6FragHdr;

#define IPV6_EXTHDR_GET_RAW_FH_NH(p)        ((p)->ip6eh.ip6fh->ip6fh_nxt)
#define IPV6_EXTHDR_GET_RAW_FH_HDRLEN(p)    sizeof(IPV6FragHdr)
#define IPV6_EXTHDR_GET_RAW_FH_OFFSET(p)    (ntohs((p)->ip6eh.ip6fh->ip6fh_offlg) & 0xFFF8)
#define IPV6_EXTHDR_GET_RAW_FH_FLAG(p)      (ntohs((p)->ip6eh.ip6fh->ip6fh_offlg) & 0x0001)
#define IPV6_EXTHDR_GET_RAW_FH_ID(p)        (ntohl((p)->ip6eh.ip6fh->ip6fh_ident))

#define IPV6_EXTHDR_GET_FH_NH(p)            IPV6_EXTHDR_GET_RAW_FH_NH((p))
#define IPV6_EXTHDR_GET_FH_HDRLEN(p)        IPV6_EXTHDR_GET_RAW_FH_HDRLEN((p))
#define IPV6_EXTHDR_GET_FH_OFFSET(p)        IPV6_EXTHDR_GET_RAW_FH_OFFSET((p))
#define IPV6_EXTHDR_GET_FH_FLAG(p)          IPV6_EXTHDR_GET_RAW_FH_FLAG((p))
#define IPV6_EXTHDR_GET_FH_ID(p)            IPV6_EXTHDR_GET_RAW_FH_ID((p))

/* rfc 1826 */
typedef struct _IPV6AuthHdr
{
    u_int8_t ip6ah_nxt;              /* next header */
    u_int8_t ip6ah_len;              /* header length in units of 8 bytes, not
                                        including first 8 bytes. */
    u_int16_t ip6ah_reserved;        /* reserved for future use */
    u_int32_t ip6ah_spi;             /* SECURITY PARAMETERS INDEX (SPI) */
    u_int32_t ip6ah_seq;             /* sequence number */
} IPV6AuthHdr;

typedef struct _IPV6EspHdr
{
    u_int32_t ip6esph_spi;           /* SECURITY PARAMETERS INDEX (SPI) */
    u_int32_t ip6esph_seq;           /* sequence number */
} IPV6EspHdr;

typedef struct _IPV6RouteHdr
{
    u_int8_t ip6rh_nxt;               /* next header */
    u_int8_t ip6rh_len;               /* header length in units of 8 bytes, not
                                        including first 8 bytes. */
    u_int8_t ip6rh_type;              /* routing type */
    u_int8_t ip6rh_segsleft;          /* segments left */
    struct in6_addr ip6rh0_addr[23];  /* type 0 addresses */
    u_int8_t ip6rh0_num_addrs;        /* number of actual addresses in the
                                        array/packet. The array is guarranteed
                                        to be filled up to this number. */
} IPV6RouteHdr;

#define IPV6_EXTHDR_GET_RAW_RH_NH(p)        ((p)->ip6eh.ip6rh->ip6rh_nxt)
#define IPV6_EXTHDR_GET_RAW_RH_HDRLEN(p)    ((p)->ip6eh.ip6rh->ip6rh_len)
#define IPV6_EXTHDR_GET_RAW_RH_TYPE(p)      (ntohs((p)->ip6eh.ip6rh->ip6rh_type))
/* XXX */

#define IPV6_EXTHDR_GET_RH_NH(p)            IPV6_EXTHDR_GET_RAW_RH_NH((p))
#define IPV6_EXTHDR_GET_RH_HDRLEN(p)        IPV6_EXTHDR_GET_RAW_RH_HDRLEN((p))
#define IPV6_EXTHDR_GET_RH_TYPE(p)          IPV6_EXTHDR_GET_RAW_RH_TYPE((p))
/* XXX */


/* Hop-by-Hop header and Destination Options header use options that are
 * defined here. */

#define IPV6OPT_PADN                  0x01
#define IPV6OPT_RA                    0x05
#define IPV6OPT_JUMBO                 0xC2
#define IPV6OPT_HAO                   0xC9

/* Home Address Option */
typedef struct _IPV6OptHAO
{
    u_int8_t ip6hao_type;             /* Option type */
    u_int8_t ip6hao_len;              /* Option Data len (excludes type and len) */
    struct in6_addr ip6hao_hoa;       /* Home address. */
} IPV6OptHAO;

/* Router Alert Option */
typedef struct _IPV6OptRA
{
    u_int8_t ip6ra_type;             /* Option type */
    u_int8_t ip6ra_len;              /* Option Data len (excludes type and len) */
    u_int16_t ip6ra_value;           /* Router Alert value */
} IPV6OptRA;

/* Jumbo Option */
typedef struct _IPV6OptJumbo
{
    u_int8_t ip6j_type;             /* Option type */
    u_int8_t ip6j_len;              /* Option Data len (excludes type and len) */
    u_int32_t ip6j_payload_len;     /* Jumbo Payload Length */
} IPV6OptJumbo;

typedef struct _IPV6HopOptsHdr
{
    u_int8_t ip6hh_nxt;              /* next header */
    u_int8_t ip6hh_len;              /* header length in units of 8 bytes, not
                                       including first 8 bytes. */
} IPV6HopOptsHdr;

#define IPV6_EXTHDR_GET_RAW_HH_NH(p)        ((p)->ip6eh.ip6hh->ip6hh_nxt)
#define IPV6_EXTHDR_GET_RAW_HH_HDRLEN(p)    ((p)->ip6eh.ip6hh->ip6hh_len)
/* XXX */

#define IPV6_EXTHDR_GET_HH_NH(p)            IPV6_EXTHDR_GET_RAW_HH_NH((p))
#define IPV6_EXTHDR_GET_HH_HDRLEN(p)        IPV6_EXTHDR_GET_RAW_HH_HDRLEN((p))
/* XXX */

typedef struct _IPV6DstOptsHdr
{
    u_int8_t ip6dh_nxt;              /* next header */
    u_int8_t ip6dh_len;              /* header length in units of 8 bytes, not
                                       including first 8 bytes. */
} IPV6DstOptsHdr;

#define IPV6_EXTHDR_GET_RAW_DH1_NH(p)        ((p)->ip6eh.ip6dh1->ip6dh_nxt)
#define IPV6_EXTHDR_GET_RAW_DH1_HDRLEN(p)    ((p)->ip6eh.ip6dh1->ip6dh_len)
/* XXX */

#define IPV6_EXTHDR_GET_DH1_NH(p)            IPV6_EXTHDR_GET_RAW_DH1_NH((p))
#define IPV6_EXTHDR_GET_DH1_HDRLEN(p)        IPV6_EXTHDR_GET_RAW_DH1_HDRLEN((p))
/* XXX */

#define IPV6_EXTHDR_GET_RAW_DH2_NH(p)        ((p)->ip6eh.ip6dh2->ip6dh_nxt)
#define IPV6_EXTHDR_GET_RAW_DH2_HDRLEN(p)    ((p)->ip6eh.ip6dh2->ip6dh_len)
/* XXX */

#define IPV6_EXTHDR_GET_DH2_NH(p)            IPV6_EXTHDR_GET_RAW_DH2_NH((p))
#define IPV6_EXTHDR_GET_DH2_HDRLEN(p)        IPV6_EXTHDR_GET_RAW_DH2_HDRLEN((p))
/* XXX */

typedef struct _IPV6GenOptHdr
{
    u_int8_t type;
    u_int8_t next;
    u_int8_t len;
    u_int8_t *data;
}   IPV6GenOptHdr;

typedef struct _IPV6ExtHdrs
{
    IPV6FragHdr    *ip6fh;
    /* In fh_offset we store the offset of this extension into the packet past
     * the ipv6 header. We use it in defrag for creating a defragmented packet
     * without the frag header */
    u_int16_t      fh_offset;

    IPV6RouteHdr   *ip6rh;
    IPV6AuthHdr    *ip6ah;
    IPV6EspHdr     *ip6eh;
    IPV6DstOptsHdr *ip6dh1;
    IPV6DstOptsHdr *ip6dh2;
    IPV6HopOptsHdr *ip6hh;

    /* Hop-By-Hop options */
    IPV6OptHAO ip6hh_opt_hao;
    IPV6OptRA ip6hh_opt_ra;
    IPV6OptJumbo ip6hh_opt_jumbo;
    /* Dest Options 1 */
    IPV6OptHAO ip6dh1_opt_hao;
    IPV6OptRA ip6dh1_opt_ra;
    IPV6OptJumbo ip6dh1_opt_jumbo;
    /* Dest Options 2 */
    IPV6OptHAO ip6dh2_opt_hao;
    IPV6OptRA ip6dh2_opt_ra;
    IPV6OptJumbo ip6dh2_opt_jumbo;

    IPV6GenOptHdr ip6_exthdrs[IPV6_MAX_OPT];
    u_int8_t ip6_exthdrs_cnt;

} IPV6ExtHdrs;

#define IPV6_EXTHDR_FH(p)             (p)->ip6eh.ip6fh
#define IPV6_EXTHDR_RH(p)             (p)->ip6eh.ip6rh
#define IPV6_EXTHDR_AH(p)             (p)->ip6eh.ip6ah
#define IPV6_EXTHDR_EH(p)             (p)->ip6eh.ip6eh
#define IPV6_EXTHDR_DH1(p)            (p)->ip6eh.ip6dh1
#define IPV6_EXTHDR_DH2(p)            (p)->ip6eh.ip6dh2
#define IPV6_EXTHDR_HH(p)             (p)->ip6eh.ip6hh

#define IPV6_EXTHDR_HH_HAO(p)         (p)->ip6eh.ip6hh_opt_hao
#define IPV6_EXTHDR_DH1_HAO(p)        (p)->ip6eh.ip6dh1_opt_hao
#define IPV6_EXTHDR_DH2_HAO(p)        (p)->ip6eh.ip6dh2_opt_hao
#define IPV6_EXTHDR_HH_RA(p)          (p)->ip6eh.ip6hh_opt_ra
#define IPV6_EXTHDR_DH1_RA(p)         (p)->ip6eh.ip6dh1_opt_ra
#define IPV6_EXTHDR_DH2_RA(p)         (p)->ip6eh.ip6dh2_opt_ra
#define IPV6_EXTHDR_HH_JUMBO(p)       (p)->ip6eh.ip6hh_opt_jumbo
#define IPV6_EXTHDR_DH1_JUMBO(p)      (p)->ip6eh.ip6dh1_opt_jumbo
#define IPV6_EXTHDR_DH2_JUMBO(p)      (p)->ip6eh.ip6dh2_opt_jumbo

#define IPV6_EXTHDR_SET_FH(p,pkt)     IPV6_EXTHDR_FH((p)) = (IPV6FragHdr *)pkt
#define IPV6_EXTHDR_ISSET_FH(p)       (IPV6_EXTHDR_FH((p)) != NULL)
#define IPV6_EXTHDR_SET_RH(p,pkt)     IPV6_EXTHDR_RH((p)) = (IPV6RouteHdr *)pkt
#define IPV6_EXTHDR_ISSET_RH(p)       (IPV6_EXTHDR_RH((p)) != NULL)
#define IPV6_EXTHDR_SET_AH(p,pkt)     IPV6_EXTHDR_AH((p)) = (IPV6AuthHdr *)pkt
#define IPV6_EXTHDR_ISSET_AH(p)       (IPV6_EXTHDR_AH((p)) != NULL)
#define IPV6_EXTHDR_SET_EH(p,pkt)     IPV6_EXTHDR_EH((p)) = (IPV6EspHdr *)pkt
#define IPV6_EXTHDR_ISSET_EH(p)       (IPV6_EXTHDR_EH((p)) != NULL)
#define IPV6_EXTHDR_SET_DH1(p,pkt)    IPV6_EXTHDR_DH1((p)) = (IPV6DstOptsHdr *)pkt
#define IPV6_EXTHDR_ISSET_DH1(p)      (IPV6_EXTHDR_DH1((p)) != NULL)
#define IPV6_EXTHDR_SET_DH2(p,pkt)    IPV6_EXTHDR_DH2((p)) = (IPV6DstOptsHdr *)pkt
#define IPV6_EXTHDR_ISSET_DH2(p)      (IPV6_EXTHDR_DH2((p)) != NULL)
#define IPV6_EXTHDR_SET_HH(p,pkt)     IPV6_EXTHDR_HH((p)) = (IPV6HopOptsHdr *)pkt
#define IPV6_EXTHDR_ISSET_HH(p)       (IPV6_EXTHDR_HH((p)) != NULL)

#endif /* __DECODE_IPV6_H__ */