C++ EXTRACT_BE_U_4函数代码示例

static inline void
ipnet_hdr_print(netdissect_options *ndo, const u_char *bp, u_int length)
{
	const ipnet_hdr_t *hdr;
	hdr = (const ipnet_hdr_t *)bp;

	ND_TCHECK_SIZE(hdr);
	ND_PRINT("%u > %u", EXTRACT_BE_U_4(hdr->iph_zsrc),
		  EXTRACT_BE_U_4(hdr->iph_zdst));

	if (!ndo->ndo_qflag) {
		ND_PRINT(", family %s (%u)",
                          tok2str(ipnet_values, "Unknown",
                                  EXTRACT_U_1(hdr->iph_family)),
                          EXTRACT_U_1(hdr->iph_family));
        } else {
		ND_PRINT(", %s",
                          tok2str(ipnet_values,
                                  "Unknown Ethertype (0x%04x)",
				  EXTRACT_U_1(hdr->iph_family)));
        }

	ND_PRINT(", length %u: ", length);
	return;
trunc:
	ND_PRINT(" %s", tstr);
}

static const uint32_t *
parsev3rddirres(netdissect_options *ndo,
                const uint32_t *dp, int verbose)
{
	u_int er;

	if (!(dp = parsestatus(ndo, dp, &er)))
		return (0);
	if (ndo->ndo_vflag)
		ND_PRINT(" POST:");
	if (!(dp = parse_post_op_attr(ndo, dp, verbose)))
		return (0);
	if (er)
		return dp;
	if (ndo->ndo_vflag) {
		ND_TCHECK_4(dp + 1);
		/*
		 * This displays the 8 bytes of the verifier in order,
		 * from the low-order byte to the high-order byte.
		 */
		ND_PRINT(" verf %08x%08x",
			  EXTRACT_BE_U_4(dp), EXTRACT_BE_U_4(dp + 1));
		dp += 2;
	}
	return dp;
trunc:
	return (NULL);
}

void
nfsreply_print(netdissect_options *ndo,
               const u_char *bp, u_int length,
               const u_char *bp2)
{
	const struct sunrpc_msg *rp;
	char srcid[20], dstid[20];	/*fits 32bit*/

	nfserr = 0;		/* assume no error */
	rp = (const struct sunrpc_msg *)bp;

	ND_TCHECK_4(rp->rm_xid);
	if (!ndo->ndo_nflag) {
		strlcpy(srcid, "nfs", sizeof(srcid));
		snprintf(dstid, sizeof(dstid), "%u",
		    EXTRACT_BE_U_4(rp->rm_xid));
	} else {
		snprintf(srcid, sizeof(srcid), "%u", NFS_PORT);
		snprintf(dstid, sizeof(dstid), "%u",
		    EXTRACT_BE_U_4(rp->rm_xid));
	}
	print_nfsaddr(ndo, bp2, srcid, dstid);

	nfsreply_noaddr_print(ndo, bp, length, bp2);
	return;

trunc:
	if (!nfserr)
		ND_PRINT("%s", tstr);
}

void
nfsreply_noaddr_print(netdissect_options *ndo,
                      const u_char *bp, u_int length,
                      const u_char *bp2)
{
	const struct sunrpc_msg *rp;
	uint32_t proc, vers, reply_stat;
	enum sunrpc_reject_stat rstat;
	uint32_t rlow;
	uint32_t rhigh;
	enum sunrpc_auth_stat rwhy;

	nfserr = 0;		/* assume no error */
	rp = (const struct sunrpc_msg *)bp;

	ND_TCHECK(rp->rm_reply.rp_stat);
	reply_stat = EXTRACT_BE_U_4(&rp->rm_reply.rp_stat);
	switch (reply_stat) {

	case SUNRPC_MSG_ACCEPTED:
		ND_PRINT("reply ok %u", length);
		if (xid_map_find(rp, bp2, &proc, &vers) >= 0)
			interp_reply(ndo, rp, proc, vers, length);
		break;

	case SUNRPC_MSG_DENIED:
		ND_PRINT("reply ERR %u: ", length);
		ND_TCHECK(rp->rm_reply.rp_reject.rj_stat);
		rstat = EXTRACT_BE_U_4(&rp->rm_reply.rp_reject.rj_stat);
		switch (rstat) {

		case SUNRPC_RPC_MISMATCH:
			ND_TCHECK(rp->rm_reply.rp_reject.rj_vers.high);
			rlow = EXTRACT_BE_U_4(&rp->rm_reply.rp_reject.rj_vers.low);
			rhigh = EXTRACT_BE_U_4(&rp->rm_reply.rp_reject.rj_vers.high);
			ND_PRINT("RPC Version mismatch (%u-%u)", rlow, rhigh);
			break;

		case SUNRPC_AUTH_ERROR:
			ND_TCHECK(rp->rm_reply.rp_reject.rj_why);
			rwhy = EXTRACT_BE_U_4(&rp->rm_reply.rp_reject.rj_why);
			ND_PRINT("Auth %s", tok2str(sunrpc_auth_str, "Invalid failure code %u", rwhy));
			break;

		default:
			ND_PRINT("Unknown reason for rejecting rpc message %u", (unsigned int)rstat);
			break;
		}
		break;

	default:
		ND_PRINT("reply Unknown rpc response code=%u %u", reply_stat, length);
		break;
	}
	return;

trunc:
	if (!nfserr)
		ND_PRINT("%s", tstr);
}

/*
 * Return a pointer to the first file handle in the packet.
 * If the packet was truncated, return 0.
 */
static const uint32_t *
parsereq(netdissect_options *ndo,
         const struct sunrpc_msg *rp, u_int length)
{
	const uint32_t *dp;
	u_int len;

	/*
	 * find the start of the req data (if we captured it)
	 */
	dp = (const uint32_t *)&rp->rm_call.cb_cred;
	ND_TCHECK_4(dp + 1);
	len = EXTRACT_BE_U_4(dp + 1);
	if (len < length) {
		dp += (len + (2 * sizeof(*dp) + 3)) / sizeof(*dp);
		ND_TCHECK_4(dp + 1);
		len = EXTRACT_BE_U_4(dp + 1);
		if (len < length) {
			dp += (len + (2 * sizeof(*dp) + 3)) / sizeof(*dp);
			ND_TCHECK_LEN(dp, 0);
			return (dp);
		}
	}
trunc:
	return (NULL);
}

static void
print_attr_address(netdissect_options *ndo,
                   const u_char *data, u_int length, u_short attr_code)
{
   if (length != 4)
   {
       ND_PRINT("ERROR: length %u != 4", length);
       return;
   }

   ND_TCHECK_4(data);

   switch(attr_code)
   {
      case FRM_IPADDR:
      case LOG_IPHOST:
           if (EXTRACT_BE_U_4(data) == 0xFFFFFFFF )
              ND_PRINT("User Selected");
           else
              if (EXTRACT_BE_U_4(data) == 0xFFFFFFFE )
                 ND_PRINT("NAS Select");
              else
                 ND_PRINT("%s",ipaddr_string(ndo, data));
      break;

      default:
          ND_PRINT("%s", ipaddr_string(ndo, data));
      break;
   }

   return;

   trunc:
     nd_print_trunc(ndo);
}

static void
pptp_bearer_cap_print(netdissect_options *ndo,
                      const nd_uint32_t *bearer_cap)
{
	ND_PRINT(" BEARER_CAP(%s%s)",
	          EXTRACT_BE_U_4(*bearer_cap) & PPTP_BEARER_CAP_DIGITAL_MASK ? "D" : "",
	          EXTRACT_BE_U_4(*bearer_cap) & PPTP_BEARER_CAP_ANALOG_MASK ? "A" : "");
}

/*
 * Print RRCP requests
 */
void
rrcp_print(netdissect_options *ndo,
	  const u_char *cp,
	  u_int length _U_,
	  const struct lladdr_info *src,
	  const struct lladdr_info *dst)
{
	uint8_t rrcp_proto;
	uint8_t rrcp_opcode;

	ndo->ndo_protocol = "rrcp";
	ND_TCHECK_1(cp + RRCP_PROTO_OFFSET);
	rrcp_proto = EXTRACT_U_1(cp + RRCP_PROTO_OFFSET);
	ND_TCHECK_1(cp + RRCP_OPCODE_ISREPLY_OFFSET);
	rrcp_opcode = EXTRACT_U_1((cp + RRCP_OPCODE_ISREPLY_OFFSET)) & RRCP_OPCODE_MASK;
	if (src != NULL && dst != NULL) {
		ND_PRINT("%s > %s, ",
			(src->addr_string)(ndo, src->addr),
			(dst->addr_string)(ndo, dst->addr));
	}
	ND_PRINT("%s %s",
		tok2str(proto_values,"RRCP-0x%02x",rrcp_proto),
		((EXTRACT_U_1(cp + RRCP_OPCODE_ISREPLY_OFFSET)) & RRCP_ISREPLY) ? "reply" : "query");
	if (rrcp_proto==1){
    	    ND_PRINT(": %s",
		     tok2str(opcode_values,"unknown opcode (0x%02x)",rrcp_opcode));
	}
	if (rrcp_opcode==1 || rrcp_opcode==2){
	    ND_TCHECK_6(cp + RRCP_REG_ADDR_OFFSET);
    	    ND_PRINT(" addr=0x%04x, data=0x%08x",
		     EXTRACT_LE_U_2(cp + RRCP_REG_ADDR_OFFSET),
		     EXTRACT_LE_U_4(cp + RRCP_REG_DATA_OFFSET));
	}
	if (rrcp_proto==1){
	    ND_TCHECK_2(cp + RRCP_AUTHKEY_OFFSET);
    	    ND_PRINT(", auth=0x%04x",
		  EXTRACT_BE_U_2(cp + RRCP_AUTHKEY_OFFSET));
	}
	if (rrcp_proto==1 && rrcp_opcode==0 &&
	     ((EXTRACT_U_1(cp + RRCP_OPCODE_ISREPLY_OFFSET)) & RRCP_ISREPLY)){
	    ND_TCHECK_4(cp + RRCP_VENDOR_ID_OFFSET);
	    ND_PRINT(" downlink_port=%u, uplink_port=%u, uplink_mac=%s, vendor_id=%08x ,chip_id=%04x ",
		     EXTRACT_U_1(cp + RRCP_DOWNLINK_PORT_OFFSET),
		     EXTRACT_U_1(cp + RRCP_UPLINK_PORT_OFFSET),
		     etheraddr_string(ndo, cp + RRCP_UPLINK_MAC_OFFSET),
		     EXTRACT_BE_U_4(cp + RRCP_VENDOR_ID_OFFSET),
		     EXTRACT_BE_U_2(cp + RRCP_CHIP_ID_OFFSET));
	}else if (rrcp_opcode==1 || rrcp_opcode==2 || rrcp_proto==2){
	    ND_TCHECK_4(cp + RRCP_COOKIE2_OFFSET);
	    ND_PRINT(", cookie=0x%08x%08x ",
		    EXTRACT_BE_U_4(cp + RRCP_COOKIE2_OFFSET),
		    EXTRACT_BE_U_4(cp + RRCP_COOKIE1_OFFSET));
	}
	return;

trunc:
	nd_print_trunc(ndo);
}

static const uint32_t *
parse_wcc_attr(netdissect_options *ndo,
               const uint32_t *dp)
{
	/* Our caller has already checked this */
	ND_PRINT(" sz %" PRIu64, EXTRACT_BE_U_8(dp));
	ND_PRINT(" mtime %u.%06u ctime %u.%06u",
	       EXTRACT_BE_U_4(dp + 2), EXTRACT_BE_U_4(dp + 3),
	       EXTRACT_BE_U_4(dp + 4), EXTRACT_BE_U_4(dp + 5));
	return (dp + 6);
}

/*
 * Return a pointer to the first file handle in the packet.
 * If the packet was truncated, return 0.
 */
static const uint32_t *
parsereq(netdissect_options *ndo,
         const struct sunrpc_msg *rp, u_int length)
{
	const uint32_t *dp;
	u_int len, rounded_len;

	/*
	 * Find the start of the req data (if we captured it).
	 * First, get the length of the credentials, and make sure
	 * we have all of the opaque part of the credentials.
	 */
	dp = (const uint32_t *)&rp->rm_call.cb_cred;
	if (length < 2 * sizeof(*dp))
		goto trunc;
	ND_TCHECK_4(dp + 1);
	len = EXTRACT_BE_U_4(dp + 1);
	rounded_len = roundup2(len, 4);
	ND_TCHECK_LEN(dp + 2, rounded_len);
	if (2 * sizeof(*dp) + rounded_len <= length) {
		/*
		 * We have all of the credentials.  Skip past them; they
		 * consist of 4 bytes of flavor, 4 bytes of length,
		 * and len-rounded-up-to-a-multiple-of-4 bytes of
		 * data.
		 */
		dp += (len + (2 * sizeof(*dp) + 3)) / sizeof(*dp);
		length -= 2 * sizeof(*dp) + rounded_len;

		/*
		 * Now get the length of the verifier, and make sure
		 * we have all of the opaque part of the verifier.
		 */
		if (length < 2 * sizeof(*dp))
			goto trunc;
		ND_TCHECK_4(dp + 1);
		len = EXTRACT_BE_U_4(dp + 1);
		rounded_len = roundup2(len, 4);
		ND_TCHECK_LEN(dp + 2, rounded_len);
		if (2 * sizeof(*dp) + rounded_len < length) {
			/*
			 * We have all of the verifier.  Skip past it;
			 * it consists of 4 bytes of flavor, 4 bytes of
			 * length, and len-rounded-up-to-a-multiple-of-4
			 * bytes of data.
			 */
			dp += (len + (2 * sizeof(*dp) + 3)) / sizeof(*dp);
			return (dp);
		}
	}
trunc:
	return (NULL);
}

static void
pptp_framing_cap_print(netdissect_options *ndo,
                       const nd_uint32_t *framing_cap)
{
	ND_PRINT(" FRAME_CAP(");
	if (EXTRACT_BE_U_4(*framing_cap) & PPTP_FRAMING_CAP_ASYNC_MASK) {
                ND_PRINT("A");		/* Async */
        }
        if (EXTRACT_BE_U_4(*framing_cap) & PPTP_FRAMING_CAP_SYNC_MASK) {
                ND_PRINT("S");		/* Sync */
        }
	ND_PRINT(")");
}

/*
 * Return a pointer to the beginning of the actual results.
 * If the packet was truncated, return 0.
 */
static const uint32_t *
parserep(netdissect_options *ndo,
         const struct sunrpc_msg *rp, u_int length)
{
	const uint32_t *dp;
	u_int len;
	enum sunrpc_accept_stat astat;

	/*
	 * Portability note:
	 * Here we find the address of the ar_verf credentials.
	 * Originally, this calculation was
	 *	dp = (uint32_t *)&rp->rm_reply.rp_acpt.ar_verf
	 * On the wire, the rp_acpt field starts immediately after
	 * the (32 bit) rp_stat field.  However, rp_acpt (which is a
	 * "struct accepted_reply") contains a "struct opaque_auth",
	 * whose internal representation contains a pointer, so on a
	 * 64-bit machine the compiler inserts 32 bits of padding
	 * before rp->rm_reply.rp_acpt.ar_verf.  So, we cannot use
	 * the internal representation to parse the on-the-wire
	 * representation.  Instead, we skip past the rp_stat field,
	 * which is an "enum" and so occupies one 32-bit word.
	 */
	dp = ((const uint32_t *)&rp->rm_reply) + 1;
	ND_TCHECK_4(dp + 1);
	len = EXTRACT_BE_U_4(dp + 1);
	if (len >= length)
		return (NULL);
	/*
	 * skip past the ar_verf credentials.
	 */
	dp += (len + (2*sizeof(uint32_t) + 3)) / sizeof(uint32_t);

	/*
	 * now we can check the ar_stat field
	 */
	ND_TCHECK_4(dp);
	astat = (enum sunrpc_accept_stat) EXTRACT_BE_U_4(dp);
	if (astat != SUNRPC_SUCCESS) {
		ND_PRINT(" %s", tok2str(sunrpc_str, "ar_stat %u", astat));
		nfserr = 1;		/* suppress trunc string */
		return (NULL);
	}
	/* successful return */
	ND_TCHECK_LEN(dp, sizeof(astat));
	return ((const uint32_t *) (sizeof(astat) + ((const char *)dp)));
trunc:
	return (0);
}

/*
 * Print out a file name and return pointer to 32-bit word past it.
 * If packet was truncated, return 0.
 */
static const uint32_t *
parsefn(netdissect_options *ndo,
        const uint32_t *dp)
{
	uint32_t len;
	const u_char *cp;

	/* Bail if we don't have the string length */
	ND_TCHECK_4(dp);

	/* Fetch big-endian string length */
	len = EXTRACT_BE_U_4(dp);
	dp++;

	ND_TCHECK_LEN(dp, ((len + 3) & ~3));

	cp = (const u_char *)dp;
	/* Update 32-bit pointer (NFS filenames padded to 32-bit boundaries) */
	dp += ((len + 3) & ~3) / sizeof(*dp);
	ND_PRINT("\"");
	if (fn_printn(ndo, cp, len, ndo->ndo_snapend)) {
		ND_PRINT("\"");
		goto trunc;
	}
	ND_PRINT("\"");

	return (dp);
trunc:
	return NULL;
}

/*
 * This is the top level routine of the printer.  'p' points
 * to the bluetooth header of the packet, 'h->ts' is the timestamp,
 * 'h->len' is the length of the packet off the wire, and 'h->caplen'
 * is the number of bytes actually captured.
 */
u_int
bt_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p)
{
	u_int length = h->len;
	u_int caplen = h->caplen;
	const pcap_bluetooth_h4_header* hdr = (const pcap_bluetooth_h4_header*)p;

	ndo->ndo_protocol = "bt_if";
	if (caplen < BT_HDRLEN || length < BT_HDRLEN)
		goto trunc;
	caplen -= BT_HDRLEN;
	length -= BT_HDRLEN;
	p += BT_HDRLEN;
	ND_TCHECK_4(&hdr->direction);
	if (ndo->ndo_eflag)
		ND_PRINT("hci length %u, direction %s, ", length,
			 (EXTRACT_BE_U_4(&hdr->direction)&0x1) ? "in" : "out");

	if (!ndo->ndo_suppress_default_print)
		ND_DEFAULTPRINT(p, caplen);

trunc:
	ND_PRINT("%s", tstr);
	return (BT_HDRLEN);
}

static const uint32_t *
parsecreateopres(netdissect_options *ndo,
                 const uint32_t *dp, int verbose)
{
	u_int er;

	if (!(dp = parsestatus(ndo, dp, &er)))
		return (0);
	if (er)
		dp = parse_wcc_data(ndo, dp, verbose);
	else {
		ND_TCHECK_4(dp);
		if (!EXTRACT_BE_U_4(dp))
			return (dp + 1);
		dp++;
		if (!(dp = parsefh(ndo, dp, 1)))
			return (0);
		if (verbose) {
			if (!(dp = parse_post_op_attr(ndo, dp, verbose)))
				return (0);
			if (ndo->ndo_vflag > 1) {
				ND_PRINT(" dir attr:");
				dp = parse_wcc_data(ndo, dp, verbose);
			}
		}
	}
	return (dp);
trunc:
	return (NULL);
}