print-bgp.c

来自「TCPDUMP的C语言源代码,是在数据链路层的应用」· C语言 代码 · 共 1,792 行 · 第 1/5 页

		return -1;

        plen-=(24+64); /* adjust prefixlen - labellength - RD len*/

	if (32 < plen)
		return -1;

	memset(&addr, 0, sizeof(addr));
	TCHECK2(pptr[12], (plen + 7) / 8);
	memcpy(&addr, &pptr[12], (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, "RD: %s, %s/%d, label:%u %s",
                 bgp_vpn_rd_print(pptr+4),
                 getname((u_char *)&addr),
                 plen,
                 EXTRACT_24BITS(pptr+1)>>4,
                 ((pptr[3]&1)==0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );

	return 12 + (plen + 7) / 8;

trunc:
	return -2;
}

#define BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_I_PMSI   1
#define BGP_MULTICAST_VPN_ROUTE_TYPE_INTER_AS_I_PMSI   2
#define BGP_MULTICAST_VPN_ROUTE_TYPE_S_PMSI            3
#define BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_SEG_LEAF 4
#define BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_ACTIVE     5
#define BGP_MULTICAST_VPN_ROUTE_TYPE_SHARED_TREE_JOIN  6
#define BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_TREE_JOIN  7

static struct tok bgp_multicast_vpn_route_type_values[] = {
    { BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_I_PMSI, "Intra-AS I-PMSI"},
    { BGP_MULTICAST_VPN_ROUTE_TYPE_INTER_AS_I_PMSI, "Inter-AS I-PMSI"},
    { BGP_MULTICAST_VPN_ROUTE_TYPE_S_PMSI, "S-PMSI"},
    { BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_SEG_LEAF, "Intra-AS Segment-Leaf"},
    { BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_ACTIVE, "Source-Active"},
    { BGP_MULTICAST_VPN_ROUTE_TYPE_SHARED_TREE_JOIN, "Shared Tree Join"},
    { BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_TREE_JOIN, "Source Tree Join"},
};

static int
decode_multicast_vpn(const u_char *pptr, char *buf, u_int buflen)
{
        u_int8_t route_type, route_length, addr_length, sg_length;
        u_int offset;

	TCHECK2(pptr[0], 2);
        route_type = *pptr++;
        route_length = *pptr++;

        snprintf(buf, buflen, "Route-Type: %s (%u), length: %u",
                 tok2str(bgp_multicast_vpn_route_type_values,
                         "Unknown", route_type),
                 route_type, route_length);

        switch(route_type) {
        case BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_I_PMSI:
            TCHECK2(pptr[0], BGP_VPN_RD_LEN);
            offset = strlen(buf);
            snprintf(buf + offset, buflen - offset, ", RD: %s, Originator %s",
                     bgp_vpn_rd_print(pptr),
                     bgp_vpn_ip_print(pptr + BGP_VPN_RD_LEN,
                                      (route_length - BGP_VPN_RD_LEN) << 3));
            break;
        case BGP_MULTICAST_VPN_ROUTE_TYPE_INTER_AS_I_PMSI:
            TCHECK2(pptr[0], BGP_VPN_RD_LEN + 4);
            offset = strlen(buf);
            snprintf(buf + offset, buflen - offset, ", RD: %s, Source-AS %u",
                     bgp_vpn_rd_print(pptr),
                     EXTRACT_32BITS(pptr + BGP_VPN_RD_LEN));
            break;

        case BGP_MULTICAST_VPN_ROUTE_TYPE_S_PMSI:
            TCHECK2(pptr[0], BGP_VPN_RD_LEN);
            offset = strlen(buf);
            snprintf(buf + offset, buflen - offset, ", RD: %s",
                     bgp_vpn_rd_print(pptr));
            pptr += BGP_VPN_RD_LEN;

            sg_length = bgp_vpn_sg_print(pptr, buf, buflen);
            addr_length =  route_length - sg_length;

            TCHECK2(pptr[0], addr_length);
            offset = strlen(buf);
            snprintf(buf + offset, buflen - offset, ", Originator %s",
                     bgp_vpn_ip_print(pptr, addr_length << 3));
            break;

        case BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_ACTIVE:
            TCHECK2(pptr[0], BGP_VPN_RD_LEN);
            offset = strlen(buf);
            snprintf(buf + offset, buflen - offset, ", RD: %s",
                     bgp_vpn_rd_print(pptr));
            pptr += BGP_VPN_RD_LEN;

            bgp_vpn_sg_print(pptr, buf, buflen);
            break;

        case BGP_MULTICAST_VPN_ROUTE_TYPE_SHARED_TREE_JOIN: /* fall through */
        case BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_TREE_JOIN:
            TCHECK2(pptr[0], BGP_VPN_RD_LEN);
            offset = strlen(buf);
            snprintf(buf + offset, buflen - offset, ", RD: %s, Source-AS %u",
                     bgp_vpn_rd_print(pptr),
                     EXTRACT_32BITS(pptr + BGP_VPN_RD_LEN));
            pptr += BGP_VPN_RD_LEN;

            bgp_vpn_sg_print(pptr, buf, buflen);
            break;

            /*
             * no per route-type printing yet.
             */
        case BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_SEG_LEAF:
        default:
            break;
        }

        return route_length + 2;

trunc:
	return -2;
}

/*
 * As I remember, some versions of systems have an snprintf() that
 * returns -1 if the buffer would have overflowed.  If the return
 * value is negative, set buflen to 0, to indicate that we've filled
 * the buffer up.
 *
 * If the return value is greater than buflen, that means that
 * the buffer would have overflowed; again, set buflen to 0 in
 * that case.
 */
#define UPDATE_BUF_BUFLEN(buf, buflen, strlen) \
    if (strlen<0) \
       	buflen=0; \
    else if ((u_int)strlen>buflen) \
        buflen=0; \
    else { \
        buflen-=strlen; \
	buf+=strlen; \
    }

static int
decode_labeled_vpn_l2(const u_char *pptr, char *buf, u_int buflen)
{
        int plen,tlen,strlen,tlv_type,tlv_len,ttlv_len;

	TCHECK2(pptr[0], 2);
        plen=EXTRACT_16BITS(pptr);
        tlen=plen;
        pptr+=2;
	TCHECK2(pptr[0],15);
	buf[0]='\0';
        strlen=snprintf(buf, buflen, "RD: %s, CE-ID: %u, Label-Block Offset: %u, Label Base %u",
                        bgp_vpn_rd_print(pptr),
                        EXTRACT_16BITS(pptr+8),
                        EXTRACT_16BITS(pptr+10),
                        EXTRACT_24BITS(pptr+12)>>4); /* the label is offsetted by 4 bits so lets shift it right */
        UPDATE_BUF_BUFLEN(buf, buflen, strlen);
        pptr+=15;
        tlen-=15;

        /* ok now the variable part - lets read out TLVs*/
        while (tlen>0) {
            if (tlen < 3)
                return -1;
            TCHECK2(pptr[0], 3);
            tlv_type=*pptr++;
            tlv_len=EXTRACT_16BITS(pptr);
            ttlv_len=tlv_len;
            pptr+=2;

            switch(tlv_type) {
            case 1:
                if (buflen!=0) {
                    strlen=snprintf(buf,buflen, "\n\t\tcircuit status vector (%u) length: %u: 0x",
                                    tlv_type,
                                    tlv_len);
                    UPDATE_BUF_BUFLEN(buf, buflen, strlen);
                }
                ttlv_len=ttlv_len/8+1; /* how many bytes do we need to read ? */
                while (ttlv_len>0) {
                    TCHECK(pptr[0]);
                    if (buflen!=0) {
                        strlen=snprintf(buf,buflen, "%02x",*pptr++);
                        UPDATE_BUF_BUFLEN(buf, buflen, strlen);
                    }
                    ttlv_len--;
                }
                break;
            default:
                if (buflen!=0) {
                    strlen=snprintf(buf,buflen, "\n\t\tunknown TLV #%u, length: %u",
                                    tlv_type,
                                    tlv_len);
                    UPDATE_BUF_BUFLEN(buf, buflen, strlen);
                }
                break;
            }
            tlen-=(tlv_len<<3); /* the tlv-length is expressed in bits so lets shift it right */
        }
        return plen+2;

trunc:
        return -2;
}

#ifdef INET6
int
decode_prefix6(const u_char *pd, char *buf, u_int buflen)
{
	struct in6_addr addr;
	u_int plen;

	TCHECK(pd[0]);
	plen = pd[0];
	if (128 < plen)
		return -1;

	memset(&addr, 0, sizeof(addr));
	TCHECK2(pd[1], (plen + 7) / 8);
	memcpy(&addr, &pd[1], (plen + 7) / 8);
	if (plen % 8) {
		addr.s6_addr[(plen + 7) / 8 - 1] &=
			((0xff00 >> (plen % 8)) & 0xff);
	}
	snprintf(buf, buflen, "%s/%d", getname6((u_char *)&addr), plen);
	return 1 + (plen + 7) / 8;

trunc:
	return -2;
}

static int
decode_labeled_prefix6(const u_char *pptr, char *buf, u_int buflen)
{
	struct in6_addr addr;
	u_int plen;

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

	if (24 > plen)
		return -1;

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

	if (128 < plen)
		return -1;

	memset(&addr, 0, sizeof(addr));
	TCHECK2(pptr[4], (plen + 7) / 8);
	memcpy(&addr, &pptr[4], (plen + 7) / 8);
	if (plen % 8) {
		addr.s6_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",
                 getname6((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;
}

static int
decode_labeled_vpn_prefix6(const u_char *pptr, char *buf, u_int buflen)
{
	struct in6_addr addr;
	u_int plen;

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

	if ((24+64) > plen)
		return -1;

        plen-=(24+64); /* adjust prefixlen - labellength - RD len*/

	if (128 < plen)
		return -1;

	memset(&addr, 0, sizeof(addr));
	TCHECK2(pptr[12], (plen + 7) / 8);
	memcpy(&addr, &pptr[12], (plen + 7) / 8);
	if (plen % 8) {
		addr.s6_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, "RD: %s, %s/%d, label:%u %s",
                 bgp_vpn_rd_print(pptr+4),
                 getname6((u_char *)&addr),
                 plen,
                 EXTRACT_24BITS(pptr+1)>>4,
                 ((pptr[3]&1)==0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );

	return 12 + (plen + 7) / 8;

trunc:
	return -2;
}
#endif

static int
decode_clnp_prefix(const u_char *pptr, char *buf, u_int buflen)
{
        u_int8_t addr[19];
	u_int plen;

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

	if (152 < plen)
		return -1;

	memset(&addr, 0, sizeof(addr));
	TCHECK2(pptr[4], (plen + 7) / 8);
	memcpy(&addr, &pptr[4], (plen + 7) / 8);
	if (plen % 8) {
		addr[(plen + 7) / 8 - 1] &=
			((0xff00 >> (plen % 8)) & 0xff);
	}
	snprintf(buf, buflen, "%s/%d",
                 isonsap_string(addr,(plen + 7) / 8),
                 plen);

	return 1 + (plen + 7) / 8;

trunc:
	return -2;
}

static int
decode_labeled_vpn_clnp_prefix(const u_char *pptr, char *buf, u_int buflen)
{
        u_int8_t addr[19];
	u_int plen;

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

	if ((24+64) > plen)
		return -1;

        plen-=(24+64); /* adjust prefixlen - labellength - RD len*/