+ return advance;
+trunc: /* we rely on the caller to recognize -2 return value */
+ return -2;
+}
+
+static int
+bgp_attr_print(netdissect_options *ndo,
+ uint8_t atype, const u_char *pptr, u_int len,
+ const unsigned attr_set_level)
+{
+ /* allocate space for the largest possible string */
+ char astostr[AS_STR_SIZE];
+ u_int i;
+ uint16_t af;
+ uint8_t safi, snpa, nhlen;
+ int advance;
+ u_int tlen;
+ const u_char *tptr;
+ char buf[MAXHOSTNAMELEN + 100];
+ u_int as_size;
+ int add_path4, add_path6;
+ int ret;
+
+ tptr = pptr;
+ tlen = len;
+
+ switch (atype) {
+ case BGPTYPE_ORIGIN:
+ if (len != 1)
+ ND_PRINT("invalid len");
+ else {
+ ND_PRINT("%s", tok2str(bgp_origin_values,
+ "Unknown Origin Typecode",
+ GET_U_1(tptr)));
+ }
+ break;
+
+ /*
+ * Process AS4 byte path and AS2 byte path attributes here.
+ */
+ case BGPTYPE_AS4_PATH:
+ case BGPTYPE_AS_PATH:
+ if (len % 2) {
+ ND_PRINT("invalid len");
+ break;
+ }
+ if (!len) {
+ ND_PRINT("empty");
+ break;
+ }
+
+ /*
+ * BGP updates exchanged between New speakers that support 4
+ * byte AS, ASs are always encoded in 4 bytes. There is no
+ * definitive way to find this, just by the packet's
+ * contents. So, check for packet's TLV's sanity assuming
+ * 2 bytes first, and it does not pass, assume that ASs are
+ * encoded in 4 bytes format and move on.
+ */
+ as_size = bgp_attr_get_as_size(ndo, atype, pptr, len);
+
+ while (tptr < pptr + len) {
+ ND_PRINT("%s", tok2str(bgp_as_path_segment_open_values,
+ "?", GET_U_1(tptr)));
+ for (i = 0; i < GET_U_1(tptr + 1) * as_size; i += as_size) {
+ ND_TCHECK_LEN(tptr + 2 + i, as_size);
+ ND_PRINT("%s ",
+ as_printf(ndo, astostr, sizeof(astostr),
+ as_size == 2 ?
+ GET_BE_U_2(tptr + i + 2) :
+ GET_BE_U_4(tptr + i + 2)));
+ }
+ ND_PRINT("%s", tok2str(bgp_as_path_segment_close_values,
+ "?", GET_U_1(tptr)));
+ tptr += 2 + GET_U_1(tptr + 1) * as_size;
+ }
+ break;
+ case BGPTYPE_NEXT_HOP:
+ if (len != 4)
+ ND_PRINT("invalid len");
+ else {
+ ND_PRINT("%s", GET_IPADDR_STRING(tptr));
+ }
+ break;
+ case BGPTYPE_MULTI_EXIT_DISC:
+ case BGPTYPE_LOCAL_PREF:
+ if (len != 4)
+ ND_PRINT("invalid len");
+ else {
+ ND_PRINT("%u", GET_BE_U_4(tptr));
+ }
+ break;
+ case BGPTYPE_ATOMIC_AGGREGATE:
+ if (len != 0)
+ ND_PRINT("invalid len");
+ break;
+ case BGPTYPE_AGGREGATOR:
+
+ /*
+ * Depending on the AS encoded is of 2 bytes or of 4 bytes,
+ * the length of this PA can be either 6 bytes or 8 bytes.
+ */
+ if (len != 6 && len != 8) {
+ ND_PRINT("invalid len");
+ break;
+ }
+ ND_TCHECK_LEN(tptr, len);
+ if (len == 6) {
+ ND_PRINT(" AS #%s, origin %s",
+ as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_2(tptr)),
+ GET_IPADDR_STRING(tptr + 2));
+ } else {
+ ND_PRINT(" AS #%s, origin %s",
+ as_printf(ndo, astostr, sizeof(astostr),
+ GET_BE_U_4(tptr)), GET_IPADDR_STRING(tptr + 4));
+ }
+ break;
+ case BGPTYPE_AGGREGATOR4:
+ if (len != 8) {
+ ND_PRINT("invalid len");
+ break;
+ }
+ ND_PRINT(" AS #%s, origin %s",
+ as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(tptr)),
+ GET_IPADDR_STRING(tptr + 4));
+ break;
+ case BGPTYPE_COMMUNITIES:
+ if (len % 4) {
+ ND_PRINT("invalid len");
+ break;
+ }
+ while (tlen != 0) {
+ uint32_t comm;
+ ND_TCHECK_4(tptr);
+ if (tlen < 4)
+ goto trunc;
+ comm = GET_BE_U_4(tptr);
+ switch (comm) {
+ case BGP_COMMUNITY_NO_EXPORT:
+ ND_PRINT(" NO_EXPORT");
+ break;
+ case BGP_COMMUNITY_NO_ADVERT:
+ ND_PRINT(" NO_ADVERTISE");
+ break;
+ case BGP_COMMUNITY_NO_EXPORT_SUBCONFED:
+ ND_PRINT(" NO_EXPORT_SUBCONFED");
+ break;
+ default:
+ ND_PRINT("%u:%u%s",
+ (comm >> 16) & 0xffff,
+ comm & 0xffff,
+ (tlen>4) ? ", " : "");
+ break;
+ }
+ tlen -=4;
+ tptr +=4;
+ }
+ break;
+ case BGPTYPE_ORIGINATOR_ID:
+ if (len != 4) {
+ ND_PRINT("invalid len");
+ break;
+ }
+ ND_PRINT("%s",GET_IPADDR_STRING(tptr));
+ break;
+ case BGPTYPE_CLUSTER_LIST:
+ if (len % 4) {
+ ND_PRINT("invalid len");
+ break;
+ }
+ while (tlen != 0) {
+ if (tlen < 4)
+ goto trunc;
+ ND_PRINT("%s%s",
+ GET_IPADDR_STRING(tptr),
+ (tlen>4) ? ", " : "");
+ tlen -=4;
+ tptr +=4;
+ }
+ break;
+ case BGPTYPE_MP_REACH_NLRI:
+ ND_TCHECK_3(tptr);
+ if (tlen < 3)
+ goto trunc;
+ ret = bgp_mp_af_print(ndo, tptr, tlen, &af, &safi);
+ if (ret == -2)
+ goto trunc;
+ if (ret < 0)
+ break;
+
+ tptr += 3;
+ tlen -= 3;
+
+ ND_TCHECK_1(tptr);
+ if (tlen < 1)
+ goto trunc;
+ nhlen = GET_U_1(tptr);
+ tptr++;
+ tlen--;
+
+ if (nhlen) {
+ u_int nnh = 0;
+ uint8_t tnhlen = nhlen;
+ if (tlen < tnhlen)
+ goto trunc;
+ ND_PRINT("\n\t nexthop: ");
+ while (tnhlen != 0) {
+ if (nnh++ > 0) {
+ ND_PRINT(", " );
+ }
+ switch(af<<8 | safi) {
+ case (AFNUM_INET<<8 | SAFNUM_UNICAST):
+ case (AFNUM_INET<<8 | SAFNUM_MULTICAST):
+ case (AFNUM_INET<<8 | SAFNUM_UNIMULTICAST):
+ case (AFNUM_INET<<8 | SAFNUM_LABUNICAST):
+ case (AFNUM_INET<<8 | SAFNUM_RT_ROUTING_INFO):
+ case (AFNUM_INET<<8 | SAFNUM_MULTICAST_VPN):
+ case (AFNUM_INET<<8 | SAFNUM_MDT):
+ if (tnhlen < sizeof(nd_ipv4)) {
+ ND_PRINT("invalid len");
+ tptr += tnhlen;
+ tlen -= tnhlen;
+ tnhlen = 0;
+ } else {
+ ND_PRINT("%s",GET_IPADDR_STRING(tptr));
+ tptr += sizeof(nd_ipv4);
+ tnhlen -= sizeof(nd_ipv4);
+ tlen -= sizeof(nd_ipv4);
+ }
+ break;
+ case (AFNUM_INET<<8 | SAFNUM_VPNUNICAST):
+ case (AFNUM_INET<<8 | SAFNUM_VPNMULTICAST):
+ case (AFNUM_INET<<8 | SAFNUM_VPNUNIMULTICAST):
+ if (tnhlen < sizeof(nd_ipv4)+BGP_VPN_RD_LEN) {
+ ND_PRINT("invalid len");
+ tptr += tnhlen;
+ tlen -= tnhlen;
+ tnhlen = 0;
+ } else {
+ ND_PRINT("RD: %s, %s",
+ bgp_vpn_rd_print(ndo, tptr),
+ GET_IPADDR_STRING(tptr+BGP_VPN_RD_LEN));
+ tptr += (sizeof(nd_ipv4)+BGP_VPN_RD_LEN);
+ tlen -= (sizeof(nd_ipv4)+BGP_VPN_RD_LEN);
+ tnhlen -= (sizeof(nd_ipv4)+BGP_VPN_RD_LEN);
+ }
+ break;
+ case (AFNUM_INET6<<8 | SAFNUM_UNICAST):
+ case (AFNUM_INET6<<8 | SAFNUM_MULTICAST):
+ case (AFNUM_INET6<<8 | SAFNUM_UNIMULTICAST):
+ case (AFNUM_INET6<<8 | SAFNUM_LABUNICAST):
+ if (tnhlen < sizeof(nd_ipv6)) {
+ ND_PRINT("invalid len");
+ tptr += tnhlen;
+ tlen -= tnhlen;
+ tnhlen = 0;
+ } else {
+ ND_PRINT("%s", GET_IP6ADDR_STRING(tptr));
+ tptr += sizeof(nd_ipv6);
+ tlen -= sizeof(nd_ipv6);
+ tnhlen -= sizeof(nd_ipv6);
+ }
+ break;
+ case (AFNUM_INET6<<8 | SAFNUM_VPNUNICAST):
+ case (AFNUM_INET6<<8 | SAFNUM_VPNMULTICAST):
+ case (AFNUM_INET6<<8 | SAFNUM_VPNUNIMULTICAST):
+ if (tnhlen < sizeof(nd_ipv6)+BGP_VPN_RD_LEN) {
+ ND_PRINT("invalid len");
+ tptr += tnhlen;
+ tlen -= tnhlen;
+ tnhlen = 0;
+ } else {
+ ND_PRINT("RD: %s, %s",
+ bgp_vpn_rd_print(ndo, tptr),
+ GET_IP6ADDR_STRING(tptr+BGP_VPN_RD_LEN));
+ tptr += (sizeof(nd_ipv6)+BGP_VPN_RD_LEN);
+ tlen -= (sizeof(nd_ipv6)+BGP_VPN_RD_LEN);
+ tnhlen -= (sizeof(nd_ipv6)+BGP_VPN_RD_LEN);
+ }
+ break;
+ case (AFNUM_VPLS<<8 | SAFNUM_VPLS):
+ case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNICAST):
+ case (AFNUM_L2VPN<<8 | SAFNUM_VPNMULTICAST):
+ case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNIMULTICAST):
+ if (tnhlen < sizeof(nd_ipv4)) {
+ ND_PRINT("invalid len");
+ tptr += tnhlen;
+ tlen -= tnhlen;
+ tnhlen = 0;
+ } else {
+ ND_PRINT("%s", GET_IPADDR_STRING(tptr));
+ tptr += (sizeof(nd_ipv4));
+ tlen -= (sizeof(nd_ipv4));
+ tnhlen -= (sizeof(nd_ipv4));
+ }
+ break;
+ case (AFNUM_NSAP<<8 | SAFNUM_UNICAST):
+ case (AFNUM_NSAP<<8 | SAFNUM_MULTICAST):
+ case (AFNUM_NSAP<<8 | SAFNUM_UNIMULTICAST):
+ ND_PRINT("%s", GET_ISONSAP_STRING(tptr, tnhlen));
+ tptr += tnhlen;
+ tlen -= tnhlen;
+ tnhlen = 0;
+ break;
+
+ case (AFNUM_NSAP<<8 | SAFNUM_VPNUNICAST):
+ case (AFNUM_NSAP<<8 | SAFNUM_VPNMULTICAST):
+ case (AFNUM_NSAP<<8 | SAFNUM_VPNUNIMULTICAST):
+ if (tnhlen < BGP_VPN_RD_LEN+1) {
+ ND_PRINT("invalid len");
+ tptr += tnhlen;
+ tlen -= tnhlen;
+ tnhlen = 0;
+ } else {
+ ND_TCHECK_LEN(tptr, tnhlen);
+ ND_PRINT("RD: %s, %s",
+ bgp_vpn_rd_print(ndo, tptr),
+ GET_ISONSAP_STRING(tptr+BGP_VPN_RD_LEN,tnhlen-BGP_VPN_RD_LEN));
+ /* rfc986 mapped IPv4 address ? */
+ if (GET_BE_U_4(tptr + BGP_VPN_RD_LEN) == 0x47000601)
+ ND_PRINT(" = %s", GET_IPADDR_STRING(tptr+BGP_VPN_RD_LEN+4));
+ /* rfc1888 mapped IPv6 address ? */
+ else if (GET_BE_U_3(tptr + BGP_VPN_RD_LEN) == 0x350000)
+ ND_PRINT(" = %s", GET_IP6ADDR_STRING(tptr+BGP_VPN_RD_LEN+3));
+ tptr += tnhlen;
+ tlen -= tnhlen;
+ tnhlen = 0;
+ }
+ break;
+ default:
+ /*
+ * bgp_mp_af_print() should have saved us from
+ * an unsupported AFI/SAFI.
+ */
+ ND_PRINT("ERROR: no AFI %u/SAFI %u nexthop decoder", af, safi);
+ tptr += tnhlen;
+ tlen -= tnhlen;
+ tnhlen = 0;
+ goto done;
+ break;
+ }
+ }
+ }
+ ND_PRINT(", nh-length: %u", nhlen);
+
+ /* As per RFC 2858; this is reserved in RFC 4760 */
+ if (tlen < 1)
+ goto trunc;
+ snpa = GET_U_1(tptr);
+ tptr++;
+ tlen--;
+
+ if (snpa) {
+ ND_PRINT("\n\t %u SNPA", snpa);
+ for (/*nothing*/; snpa != 0; snpa--) {
+ uint8_t snpalen;
+ if (tlen < 1)
+ goto trunc;
+ snpalen = GET_U_1(tptr);
+ ND_PRINT("\n\t %u bytes", snpalen);
+ tptr++;
+ tlen--;
+ if (tlen < snpalen)
+ goto trunc;
+ ND_TCHECK_LEN(tptr, snpalen);
+ tptr += snpalen;
+ tlen -= snpalen;
+ }
+ } else {
+ ND_PRINT(", no SNPA");
+ }
+
+ add_path4 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 32);
+ add_path6 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 128);
+
+ while (tptr < pptr + len) {
+ advance = bgp_nlri_print(ndo, af, safi, tptr, len, buf, sizeof(buf),
+ add_path4, add_path6);
+ if (advance == -2)
+ goto trunc;
+ if (advance < 0)
+ break;
+ tptr += advance;
+ }
+ break;
+
+ case BGPTYPE_MP_UNREACH_NLRI:
+ ND_TCHECK_LEN(tptr, BGP_MP_NLRI_MINSIZE);
+ ret = bgp_mp_af_print(ndo, tptr, tlen, &af, &safi);
+ if (ret == -2)
+ goto trunc;
+ if (ret < 0)
+ break;
+
+ if (len == BGP_MP_NLRI_MINSIZE)
+ ND_PRINT("\n\t End-of-Rib Marker (empty NLRI)");
+
+ tptr += 3;
+
+ add_path4 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 32);
+ add_path6 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 128);
+
+ while (tptr < pptr + len) {
+ advance = bgp_nlri_print(ndo, af, safi, tptr, len, buf, sizeof(buf),
+ add_path4, add_path6);
+ if (advance == -2)
+ goto trunc;
+ if (advance < 0)
+ break;
+ tptr += advance;
+ }
+ break;
+ case BGPTYPE_EXTD_COMMUNITIES:
+ if (len % 8) {
+ ND_PRINT("invalid len");
+ break;
+ }
+ while (tlen != 0) {
+ uint16_t extd_comm;
+
+ ND_TCHECK_2(tptr);
+ if (tlen < 2)
+ goto trunc;
+ extd_comm=GET_BE_U_2(tptr);
+
+ ND_PRINT("\n\t %s (0x%04x), Flags [%s]",
+ tok2str(bgp_extd_comm_subtype_values,
+ "unknown extd community typecode",
+ extd_comm),
+ extd_comm,
+ bittok2str(bgp_extd_comm_flag_values, "none", extd_comm));
+
+ ND_TCHECK_8(tptr);
+ if (tlen < 8)
+ goto trunc;
+ ND_PRINT(": ");
+ bgp_extended_community_print(ndo, tptr);
+ tlen -= 8;
+ tptr += 8;
+ }
+ break;
+
+ case BGPTYPE_PMSI_TUNNEL:
+ {
+ uint8_t tunnel_type, flags;
+
+ ND_TCHECK_5(tptr);
+ if (tlen < 5)
+ goto trunc;
+ flags = GET_U_1(tptr);
+ tunnel_type = GET_U_1(tptr + 1);
+
+ ND_PRINT("\n\t Tunnel-type %s (%u), Flags [%s], MPLS Label %u",
+ tok2str(bgp_pmsi_tunnel_values, "Unknown", tunnel_type),
+ tunnel_type,
+ bittok2str(bgp_pmsi_flag_values, "none", flags),
+ GET_BE_U_3(tptr + 2)>>4);
+
+ tptr +=5;
+ tlen -= 5;
+
+ switch (tunnel_type) {
+ case BGP_PMSI_TUNNEL_PIM_SM: /* fall through */
+ case BGP_PMSI_TUNNEL_PIM_BIDIR:
+ ND_PRINT("\n\t Sender %s, P-Group %s",
+ GET_IPADDR_STRING(tptr),
+ GET_IPADDR_STRING(tptr+4));
+ break;
+
+ case BGP_PMSI_TUNNEL_PIM_SSM:
+ ND_PRINT("\n\t Root-Node %s, P-Group %s",
+ GET_IPADDR_STRING(tptr),
+ GET_IPADDR_STRING(tptr+4));
+ break;
+ case BGP_PMSI_TUNNEL_INGRESS:
+ ND_PRINT("\n\t Tunnel-Endpoint %s",
+ GET_IPADDR_STRING(tptr));
+ break;
+ case BGP_PMSI_TUNNEL_LDP_P2MP: /* fall through */
+ case BGP_PMSI_TUNNEL_LDP_MP2MP:
+ ND_PRINT("\n\t Root-Node %s, LSP-ID 0x%08x",
+ GET_IPADDR_STRING(tptr),
+ GET_BE_U_4(tptr + 4));
+ break;
+ case BGP_PMSI_TUNNEL_RSVP_P2MP:
+ ND_PRINT("\n\t Extended-Tunnel-ID %s, P2MP-ID 0x%08x",
+ GET_IPADDR_STRING(tptr),
+ GET_BE_U_4(tptr + 4));
+ break;
+ default:
+ if (ndo->ndo_vflag <= 1) {
+ print_unknown_data(ndo, tptr, "\n\t ", tlen);
+ }
+ }
+ break;
+ }
+ case BGPTYPE_AIGP:
+ {
+ uint8_t type;
+ uint16_t length;
+
+ while (tlen >= 3) {
+ type = GET_U_1(tptr);
+ length = GET_BE_U_2(tptr + 1);
+ tptr += 3;
+ tlen -= 3;
+
+ ND_PRINT("\n\t %s TLV (%u), length %u",
+ tok2str(bgp_aigp_values, "Unknown", type),
+ type, length);
+
+ if (length < 3)
+ goto trunc;
+ length -= 3;
+
+ /*
+ * Check if we can read the TLV data.
+ */
+ if (tlen < length)
+ goto trunc;
+
+ switch (type) {
+
+ case BGP_AIGP_TLV:
+ if (length < 8)
+ goto trunc;
+ ND_PRINT(", metric %" PRIu64,
+ GET_BE_U_8(tptr));
+ break;
+
+ default:
+ if (ndo->ndo_vflag <= 1) {
+ print_unknown_data(ndo, tptr,"\n\t ", length);
+ }
+ }
+
+ tptr += length;
+ tlen -= length;
+ }
+ break;
+ }
+ case BGPTYPE_ATTR_SET:
+ ND_TCHECK_4(tptr);
+ if (len < 4)
+ goto trunc;
+ ND_PRINT("\n\t Origin AS: %s",
+ as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(tptr)));
+ tptr += 4;
+ len -= 4;
+
+ while (len) {
+ u_int aflags, alenlen, alen;
+
+ ND_TCHECK_2(tptr);
+ if (len < 2) {
+ ND_PRINT(" [path attr too short]");
+ tptr += len;
+ break;
+ }
+ aflags = GET_U_1(tptr);
+ atype = GET_U_1(tptr + 1);
+ tptr += 2;
+ len -= 2;
+ alenlen = bgp_attr_lenlen(aflags, tptr);
+ ND_TCHECK_LEN(tptr, alenlen);
+ if (len < alenlen) {
+ ND_PRINT(" [path attr too short]");
+ tptr += len;
+ break;
+ }
+ alen = bgp_attr_len(aflags, tptr);
+ tptr += alenlen;
+ len -= alenlen;
+
+ ND_PRINT("\n\t %s (%u), length: %u",
+ tok2str(bgp_attr_values,
+ "Unknown Attribute", atype),
+ atype,
+ alen);
+
+ if (aflags) {
+ ND_PRINT(", Flags [%s%s%s%s",
+ aflags & 0x80 ? "O" : "",
+ aflags & 0x40 ? "T" : "",
+ aflags & 0x20 ? "P" : "",
+ aflags & 0x10 ? "E" : "");
+ if (aflags & 0xf)
+ ND_PRINT("+%x", aflags & 0xf);
+ ND_PRINT("]");
+ }
+ ND_PRINT(": ");
+ if (len < alen) {
+ ND_PRINT(" [path attr too short]");
+ tptr += len;
+ break;
+ }
+ /*
+ * The protocol encoding per se allows ATTR_SET to be nested
+ * as many times as the message can accommodate. This printer
+ * used to be able to recurse into ATTR_SET contents until the
+ * stack exhaustion, but now there is a limit on that (if live
+ * protocol exchange goes that many levels deep, something is
+ * probably wrong anyway). Feel free to refine this value if
+ * you can find the spec with respective normative text.
+ */
+ if (attr_set_level == 10)
+ ND_PRINT("(too many nested levels, not recursing)");
+ else if (!bgp_attr_print(ndo, atype, tptr, alen, attr_set_level + 1))
+ return 0;
+ tptr += alen;
+ len -= alen;
+ }
+ break;
+
+ case BGPTYPE_LARGE_COMMUNITY:
+ if (len == 0 || len % 12) {
+ ND_PRINT("invalid len");
+ break;
+ }
+ ND_PRINT("\n\t ");
+ while (len != 0) {
+ ND_PRINT("%u:%u:%u%s",
+ GET_BE_U_4(tptr),
+ GET_BE_U_4(tptr + 4),
+ GET_BE_U_4(tptr + 8),
+ (len > 12) ? ", " : "");
+ tptr += 12;
+ /*
+ * len will always be a multiple of 12, as per the above,
+ * so this will never underflow.
+ */
+ len -= 12;
+ }
+ break;
+ default:
+ ND_TCHECK_LEN(pptr, len);
+ ND_PRINT("\n\t no Attribute %u decoder", atype); /* we have no decoder for the attribute */
+ if (ndo->ndo_vflag <= 1)
+ print_unknown_data(ndo, pptr, "\n\t ", len);
+ break;
+ }
+done:
+ if (ndo->ndo_vflag > 1 && len) { /* omit zero length attributes*/
+ ND_TCHECK_LEN(pptr, len);
+ print_unknown_data(ndo, pptr, "\n\t ", len);
+ }
+ return 1;
+
projects / tcpdump / blobdiff