print-bgp.c

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    { SAFNUM_RES,               "Reserved"},
    { SAFNUM_UNICAST,           "Unicast"},
    { SAFNUM_MULTICAST,         "Multicast"},
    { SAFNUM_UNIMULTICAST,      "Unicast+Multicast"},
    { SAFNUM_LABUNICAST,        "labeled Unicast"},
    { SAFNUM_TUNNEL,            "Tunnel"},
    { SAFNUM_VPLS,              "VPLS"},
    { SAFNUM_MDT,               "MDT"},
    { SAFNUM_VPNUNICAST,        "labeled VPN Unicast"},
    { SAFNUM_VPNMULTICAST,      "labeled VPN Multicast"},
    { SAFNUM_VPNUNIMULTICAST,   "labeled VPN Unicast+Multicast"},
    { SAFNUM_RT_ROUTING_INFO,   "Route Target Routing Information"},
    { SAFNUM_MULTICAST_VPN,     "Multicast VPN"},
    { 0, NULL }
};

/* well-known community */
#define BGP_COMMUNITY_NO_EXPORT			0xffffff01
#define BGP_COMMUNITY_NO_ADVERT			0xffffff02
#define BGP_COMMUNITY_NO_EXPORT_SUBCONFED	0xffffff03

/* Extended community type - draft-ietf-idr-bgp-ext-communities-05 */
#define BGP_EXT_COM_RT_0        0x0002  /* Route Target,Format AS(2bytes):AN(4bytes) */
#define BGP_EXT_COM_RT_1        0x0102  /* Route Target,Format IP address:AN(2bytes) */
#define BGP_EXT_COM_RT_2        0x0202  /* Route Target,Format AN(4bytes):local(2bytes) */
#define BGP_EXT_COM_RO_0        0x0003  /* Route Origin,Format AS(2bytes):AN(4bytes) */
#define BGP_EXT_COM_RO_1        0x0103  /* Route Origin,Format IP address:AN(2bytes) */
#define BGP_EXT_COM_RO_2        0x0203  /* Route Origin,Format AN(4bytes):local(2bytes) */
#define BGP_EXT_COM_LINKBAND    0x4004  /* Link Bandwidth,Format AS(2B):Bandwidth(4B) */
                                        /* rfc2547 bgp-mpls-vpns */
#define BGP_EXT_COM_VPN_ORIGIN  0x0005  /* OSPF Domain ID / VPN of Origin  - draft-rosen-vpns-ospf-bgp-mpls */
#define BGP_EXT_COM_VPN_ORIGIN2 0x0105  /* duplicate - keep for backwards compatability */
#define BGP_EXT_COM_VPN_ORIGIN3 0x0205  /* duplicate - keep for backwards compatability */
#define BGP_EXT_COM_VPN_ORIGIN4 0x8005  /* duplicate - keep for backwards compatability */

#define BGP_EXT_COM_OSPF_RTYPE  0x0306  /* OSPF Route Type,Format Area(4B):RouteType(1B):Options(1B) */
#define BGP_EXT_COM_OSPF_RTYPE2 0x8000  /* duplicate - keep for backwards compatability */

#define BGP_EXT_COM_OSPF_RID    0x0107  /* OSPF Router ID,Format RouterID(4B):Unused(2B) */
#define BGP_EXT_COM_OSPF_RID2   0x8001  /* duplicate - keep for backwards compatability */ 

#define BGP_EXT_COM_L2INFO      0x800a  /* draft-kompella-ppvpn-l2vpn */

#define BGP_EXT_COM_SOURCE_AS   0x0009  /* draft-ietf-l3vpn-2547bis-mcast-bgp-02.txt */
#define BGP_EXT_COM_VRF_RT_IMP  0x010a  /* draft-ietf-l3vpn-2547bis-mcast-bgp-02.txt */

/* http://www.cisco.com/en/US/tech/tk436/tk428/technologies_tech_note09186a00801eb09a.shtml  */
#define BGP_EXT_COM_EIGRP_GEN   0x8800
#define BGP_EXT_COM_EIGRP_METRIC_AS_DELAY  0x8801
#define BGP_EXT_COM_EIGRP_METRIC_REL_NH_BW 0x8802
#define BGP_EXT_COM_EIGRP_METRIC_LOAD_MTU  0x8803
#define BGP_EXT_COM_EIGRP_EXT_REMAS_REMID  0x8804
#define BGP_EXT_COM_EIGRP_EXT_REMPROTO_REMMETRIC 0x8805

static struct tok bgp_extd_comm_flag_values[] = {
    { 0x8000,                  "vendor-specific"},
    { 0x4000,                  "non-transitive"},
    { 0, NULL},
};

static struct tok bgp_extd_comm_subtype_values[] = {
    { BGP_EXT_COM_RT_0,        "target"},
    { BGP_EXT_COM_RT_1,        "target"},
    { BGP_EXT_COM_RT_2,        "target"},
    { BGP_EXT_COM_RO_0,        "origin"},
    { BGP_EXT_COM_RO_1,        "origin"},
    { BGP_EXT_COM_RO_2,        "origin"},
    { BGP_EXT_COM_LINKBAND,    "link-BW"},
    { BGP_EXT_COM_VPN_ORIGIN,  "ospf-domain"},
    { BGP_EXT_COM_VPN_ORIGIN2, "ospf-domain"},
    { BGP_EXT_COM_VPN_ORIGIN3, "ospf-domain"},
    { BGP_EXT_COM_VPN_ORIGIN4, "ospf-domain"},
    { BGP_EXT_COM_OSPF_RTYPE,  "ospf-route-type"},
    { BGP_EXT_COM_OSPF_RTYPE2, "ospf-route-type"},
    { BGP_EXT_COM_OSPF_RID,    "ospf-router-id"},
    { BGP_EXT_COM_OSPF_RID2,   "ospf-router-id"},
    { BGP_EXT_COM_L2INFO,      "layer2-info"}, 
    { BGP_EXT_COM_EIGRP_GEN , "eigrp-general-route (flag, tag)" },
    { BGP_EXT_COM_EIGRP_METRIC_AS_DELAY , "eigrp-route-metric (AS, delay)" },
    { BGP_EXT_COM_EIGRP_METRIC_REL_NH_BW , "eigrp-route-metric (reliability, nexthop, bandwidth)" },
    { BGP_EXT_COM_EIGRP_METRIC_LOAD_MTU , "eigrp-route-metric (load, MTU)" },
    { BGP_EXT_COM_EIGRP_EXT_REMAS_REMID , "eigrp-external-route (remote-AS, remote-ID)" },
    { BGP_EXT_COM_EIGRP_EXT_REMPROTO_REMMETRIC , "eigrp-external-route (remote-proto, remote-metric)" },
    { BGP_EXT_COM_SOURCE_AS, "source-AS" },
    { BGP_EXT_COM_VRF_RT_IMP, "vrf-route-import"},
    { 0, NULL},
};

/* OSPF codes for  BGP_EXT_COM_OSPF_RTYPE draft-rosen-vpns-ospf-bgp-mpls  */
#define BGP_OSPF_RTYPE_RTR      1 /* OSPF Router LSA */
#define BGP_OSPF_RTYPE_NET      2 /* OSPF Network LSA */
#define BGP_OSPF_RTYPE_SUM      3 /* OSPF Summary LSA */
#define BGP_OSPF_RTYPE_EXT      5 /* OSPF External LSA, note that ASBR doesn't apply to MPLS-VPN */
#define BGP_OSPF_RTYPE_NSSA     7 /* OSPF NSSA External*/
#define BGP_OSPF_RTYPE_SHAM     129 /* OSPF-MPLS-VPN Sham link */
#define BGP_OSPF_RTYPE_METRIC_TYPE 0x1 /* LSB of RTYPE Options Field */

static struct tok bgp_extd_comm_ospf_rtype_values[] = {
  { BGP_OSPF_RTYPE_RTR, "Router" },  
  { BGP_OSPF_RTYPE_NET, "Network" },  
  { BGP_OSPF_RTYPE_SUM, "Summary" },  
  { BGP_OSPF_RTYPE_EXT, "External" },  
  { BGP_OSPF_RTYPE_NSSA,"NSSA External" },
  { BGP_OSPF_RTYPE_SHAM,"MPLS-VPN Sham" },  
  { 0, NULL },
};

int
decode_prefix4(const u_char *pptr, char *buf, u_int buflen)
{
	struct in_addr addr;
	u_int plen;

	TCHECK(pptr[0]);
	plen = pptr[0];
	if (32 < plen)
		return -1;

	memset(&addr, 0, sizeof(addr));
	TCHECK2(pptr[1], (plen + 7) / 8);
	memcpy(&addr, &pptr[1], (plen + 7) / 8);
	if (plen % 8) {
		((u_char *)&addr)[(plen + 7) / 8 - 1] &=
			((0xff00 >> (plen % 8)) & 0xff);
	}
	snprintf(buf, buflen, "%s/%d", getname((u_char *)&addr), plen);
	return 1 + (plen + 7) / 8;

trunc:
	return -2;
}

static int
decode_labeled_prefix4(const u_char *pptr, char *buf, u_int buflen)
{
	struct in_addr addr;
	u_int plen;

	TCHECK(pptr[0]);
	plen = pptr[0];   /* get prefix length */

        /* this is one of the weirdnesses of rfc3107
           the label length (actually the label + COS bits)
           is added to the prefix length;
           we also do only read out just one label -
           there is no real application for advertisement of
           stacked labels in a a single BGP message
        */

	if (24 > plen)
		return -1;

        plen-=24; /* adjust prefixlen - labellength */

	if (32 < plen)
		return -1;

	memset(&addr, 0, sizeof(addr));
	TCHECK2(pptr[4], (plen + 7) / 8);
	memcpy(&addr, &pptr[4], (plen + 7) / 8);
	if (plen % 8) {
		((u_char *)&addr)[(plen + 7) / 8 - 1] &=
			((0xff00 >> (plen % 8)) & 0xff);
	}
        /* the label may get offsetted by 4 bits so lets shift it right */
	snprintf(buf, buflen, "%s/%d, label:%u %s",
                 getname((u_char *)&addr),
                 plen,
                 EXTRACT_24BITS(pptr+1)>>4,
                 ((pptr[3]&1)==0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );

	return 4 + (plen + 7) / 8;

trunc:
	return -2;
}

/*
 * bgp_vpn_ip_print
 *
 * print an ipv4 or ipv6 address into a buffer dependend on address length.
 */
static char *
bgp_vpn_ip_print (const u_char *pptr, u_int addr_length) {

    /* worst case string is s fully formatted v6 address */
    static char addr[sizeof("1234:5678:89ab:cdef:1234:5678:89ab:cdef")];
    char *pos = addr;

    switch(addr_length) {
    case (sizeof(struct in_addr) << 3): /* 32 */
        TCHECK2(pptr[0], sizeof(struct in_addr));
        snprintf(pos, sizeof(addr), "%s", ipaddr_string(pptr));
        break;
#ifdef INET6
    case (sizeof(struct in6_addr) << 3): /* 128 */
        TCHECK2(pptr[0], sizeof(struct in6_addr));
        snprintf(pos, sizeof(addr), "%s", ip6addr_string(pptr));
        break;
#endif
    default:
        snprintf(pos, sizeof(addr), "bogus address length %u", addr_length);
        break;
    }
    pos += strlen(pos);

trunc:
    *(pos) = '\0';
    return (addr);
}

/*
 * bgp_vpn_sg_print
 *
 * print an multicast s,g entry into a buffer.
 * the s,g entry is encoded like this.
 *
 * +-----------------------------------+
 * | Multicast Source Length (1 octet) |
 * +-----------------------------------+
 * |   Multicast Source (Variable)     |
 * +-----------------------------------+
 * |  Multicast Group Length (1 octet) |
 * +-----------------------------------+
 * |  Multicast Group   (Variable)     |
 * +-----------------------------------+
 *
 * return the number of bytes read from the wire.
 */
static int
bgp_vpn_sg_print (const u_char *pptr, char *buf, u_int buflen) {

    u_int8_t addr_length;
    u_int total_length, offset;

    total_length = 0;

    /* Source address length, encoded in bits */
    TCHECK2(pptr[0], 1);
    addr_length =  *pptr++;

    /* Source address */
    TCHECK2(pptr[0], (addr_length >> 3));
    total_length += (addr_length >> 3) + 1;
    offset = strlen(buf);
    if (addr_length) {
        snprintf(buf + offset, buflen - offset, ", Source %s",
                 bgp_vpn_ip_print(pptr, addr_length));
        pptr += (addr_length >> 3);
    }
    
    /* Group address length, encoded in bits */
    TCHECK2(pptr[0], 1);
    addr_length =  *pptr++;

    /* Group address */
    TCHECK2(pptr[0], (addr_length >> 3));
    total_length += (addr_length >> 3) + 1;
    offset = strlen(buf);
    if (addr_length) {
        snprintf(buf + offset, buflen - offset, ", Group %s",
                 bgp_vpn_ip_print(pptr, addr_length));
        pptr += (addr_length >> 3);
    }

trunc:
    return (total_length);
}


/* RDs and RTs share the same semantics
 * we use bgp_vpn_rd_print for
 * printing route targets inside a NLRI */
char *
bgp_vpn_rd_print (const u_char *pptr) {

   /* allocate space for the largest possible string */
    static char rd[sizeof("xxxxxxxxxx:xxxxx (xxx.xxx.xxx.xxx:xxxxx)")];
    char *pos = rd;

    /* ok lets load the RD format */
    switch (EXTRACT_16BITS(pptr)) {

        /* 2-byte-AS:number fmt*/
    case 0:
        snprintf(pos, sizeof(rd) - (pos - rd), "%u:%u (= %u.%u.%u.%u)",
                 EXTRACT_16BITS(pptr+2),
                 EXTRACT_32BITS(pptr+4),
                 *(pptr+4), *(pptr+5), *(pptr+6), *(pptr+7));
        break;
        /* IP-address:AS fmt*/

    case 1:
        snprintf(pos, sizeof(rd) - (pos - rd), "%u.%u.%u.%u:%u",
            *(pptr+2), *(pptr+3), *(pptr+4), *(pptr+5), EXTRACT_16BITS(pptr+6));
        break;

        /* 4-byte-AS:number fmt*/
    case 2:
        snprintf(pos, sizeof(rd) - (pos - rd), "%u:%u (%u.%u.%u.%u:%u)",
            EXTRACT_32BITS(pptr+2), EXTRACT_16BITS(pptr+6),
            *(pptr+2), *(pptr+3), *(pptr+4), *(pptr+5), EXTRACT_16BITS(pptr+6));
        break;
    default:
        snprintf(pos, sizeof(rd) - (pos - rd), "unknown RD format");
        break;
    }
    pos += strlen(pos);
    *(pos) = '\0';
    return (rd);
}

static int
decode_rt_routing_info(const u_char *pptr, char *buf, u_int buflen)
{
	u_int8_t route_target[8];
	u_int plen;

	TCHECK(pptr[0]);
	plen = pptr[0];   /* get prefix length */

	if (0 == plen)
		return 1; /* default route target */

	if (32 > plen)
		return -1;

        plen-=32; /* adjust prefix length */

	if (64 < plen)
		return -1;

	memset(&route_target, 0, sizeof(route_target));
	TCHECK2(pptr[1], (plen + 7) / 8);
	memcpy(&route_target, &pptr[1], (plen + 7) / 8);
	if (plen % 8) {
		((u_char *)&route_target)[(plen + 7) / 8 - 1] &=
			((0xff00 >> (plen % 8)) & 0xff);
	}
	snprintf(buf, buflen, "origin AS: %u, route target %s",
                 EXTRACT_32BITS(pptr+1),
                 bgp_vpn_rd_print((u_char *)&route_target));

	return 5 + (plen + 7) / 8;

trunc:
	return -2;
}

static int
decode_labeled_vpn_prefix4(const u_char *pptr, char *buf, u_int buflen)
{
	struct in_addr addr;
	u_int plen;

	TCHECK(pptr[0]);
	plen = pptr[0];   /* get prefix length */

	if ((24+64) > plen)