Adding upstream version 4.99.4.upstream/4.99.4

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1157 insertions, 0 deletions

diff --git a/print-fr.c b/print-fr.c
new file mode 100644
index 0000000..f0d7fbe
--- /dev/null
+++ b/print-fr.c
@@ -0,0 +1,1157 @@
+/*
+ * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that: (1) source code distributions
+ * retain the above copyright notice and this paragraph in its entirety, (2)
+ * distributions including binary code include the above copyright notice and
+ * this paragraph in its entirety in the documentation or other materials
+ * provided with the distribution, and (3) all advertising materials mentioning
+ * features or use of this software display the following acknowledgement:
+ * ``This product includes software developed by the University of California,
+ * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
+ * the University nor the names of its contributors may be used to endorse
+ * or promote products derived from this software without specific prior
+ * written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+/* \summary: Frame Relay printer */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "netdissect-stdinc.h"
+
+#include <stdio.h>
+#include <string.h>
+
+#include "netdissect.h"
+#include "addrtoname.h"
+#include "ethertype.h"
+#include "llc.h"
+#include "nlpid.h"
+#include "extract.h"
+
+static void frf15_print(netdissect_options *ndo, const u_char *, u_int);
+
+/*
+ * the frame relay header has a variable length
+ *
+ * the EA bit determines if there is another byte
+ * in the header
+ *
+ * minimum header length is 2 bytes
+ * maximum header length is 4 bytes
+ *
+ *      7    6    5    4    3    2    1    0
+ *    +----+----+----+----+----+----+----+----+
+ *    |        DLCI (6 bits)        | CR | EA |
+ *    +----+----+----+----+----+----+----+----+
+ *    |   DLCI (4 bits)   |FECN|BECN| DE | EA |
+ *    +----+----+----+----+----+----+----+----+
+ *    |           DLCI (7 bits)          | EA |
+ *    +----+----+----+----+----+----+----+----+
+ *    |        DLCI (6 bits)        |SDLC| EA |
+ *    +----+----+----+----+----+----+----+----+
+ */
+
+#define FR_EA_BIT	0x01
+
+#define FR_CR_BIT       0x02000000
+#define FR_DE_BIT	0x00020000
+#define FR_BECN_BIT	0x00040000
+#define FR_FECN_BIT	0x00080000
+#define FR_SDLC_BIT	0x00000002
+
+
+static const struct tok fr_header_flag_values[] = {
+    { FR_CR_BIT, "C!" },
+    { FR_DE_BIT, "DE" },
+    { FR_BECN_BIT, "BECN" },
+    { FR_FECN_BIT, "FECN" },
+    { FR_SDLC_BIT, "sdlcore" },
+    { 0, NULL }
+};
+
+/* FRF.15 / FRF.16 */
+#define MFR_B_BIT 0x80
+#define MFR_E_BIT 0x40
+#define MFR_C_BIT 0x20
+#define MFR_BEC_MASK    (MFR_B_BIT | MFR_E_BIT | MFR_C_BIT)
+#define MFR_CTRL_FRAME  (MFR_B_BIT | MFR_E_BIT | MFR_C_BIT)
+#define MFR_FRAG_FRAME  (MFR_B_BIT | MFR_E_BIT )
+
+static const struct tok frf_flag_values[] = {
+    { MFR_B_BIT, "Begin" },
+    { MFR_E_BIT, "End" },
+    { MFR_C_BIT, "Control" },
+    { 0, NULL }
+};
+
+/* Finds out Q.922 address length, DLCI and flags. Returns 1 on success,
+ * 0 on invalid address, -1 on truncated packet
+ * save the flags dep. on address length
+ */
+static int parse_q922_header(netdissect_options *ndo,
+                           const u_char *p, u_int *dlci,
+                           u_int *addr_len, uint32_t *flags, u_int length)
+{
+	if (!ND_TTEST_1(p) || length < 1)
+		return -1;
+	if ((GET_U_1(p) & FR_EA_BIT))
+		return 0;
+
+	if (!ND_TTEST_1(p + 1) || length < 2)
+		return -1;
+	*addr_len = 2;
+	*dlci = ((GET_U_1(p) & 0xFC) << 2) | ((GET_U_1(p + 1) & 0xF0) >> 4);
+
+	*flags = ((GET_U_1(p) & 0x02) << 24) |	/* CR flag */
+		 ((GET_U_1(p + 1) & 0x0e) << 16);	/* FECN,BECN,DE flags */
+
+	if (GET_U_1(p + 1) & FR_EA_BIT)
+		return 1;	/* 2-byte Q.922 address */
+
+	p += 2;
+	length -= 2;
+	if (!ND_TTEST_1(p) || length < 1)
+		return -1;
+	(*addr_len)++;		/* 3- or 4-byte Q.922 address */
+	if ((GET_U_1(p) & FR_EA_BIT) == 0) {
+		*dlci = (*dlci << 7) | (GET_U_1(p) >> 1);
+		(*addr_len)++;	/* 4-byte Q.922 address */
+		p++;
+		length--;
+	}
+
+	if (!ND_TTEST_1(p) || length < 1)
+		return -1;
+	if ((GET_U_1(p) & FR_EA_BIT) == 0)
+		return 0; /* more than 4 bytes of Q.922 address? */
+
+	*flags = *flags | (GET_U_1(p) & 0x02);	/* SDLC flag */
+
+        *dlci = (*dlci << 6) | (GET_U_1(p) >> 2);
+
+	return 1;
+}
+
+const char *
+q922_string(netdissect_options *ndo, const u_char *p, u_int length)
+{
+
+    static u_int dlci, addr_len;
+    static uint32_t flags;
+    static char buffer[sizeof("parse_q922_header() returned XXXXXXXXXXX")];
+    int ret;
+    memset(buffer, 0, sizeof(buffer));
+
+    ret = parse_q922_header(ndo, p, &dlci, &addr_len, &flags, length);
+    if (ret == 1) {
+        snprintf(buffer, sizeof(buffer), "DLCI %u", dlci);
+        return buffer;
+    } else if (ret == 0) {
+        return "<Invalid DLCI>";
+    } else if (ret == -1) {
+        return "<Truncated>";
+    } else {
+        snprintf(buffer, sizeof(buffer), "parse_q922_header() returned %d", ret);
+        return buffer;
+    }
+}
+
+
+/* Frame Relay packet structure, with flags and CRC removed
+
+                  +---------------------------+
+                  |       Q.922 Address*      |
+                  +--                       --+
+                  |                           |
+                  +---------------------------+
+                  | Control (UI = 0x03)       |
+                  +---------------------------+
+                  | Optional Pad      (0x00)  |
+                  +---------------------------+
+                  | NLPID                     |
+                  +---------------------------+
+                  |             .             |
+                  |             .             |
+                  |             .             |
+                  |           Data            |
+                  |             .             |
+                  |             .             |
+                  +---------------------------+
+
+           * Q.922 addresses, as presently defined, are two octets and
+             contain a 10-bit DLCI.  In some networks Q.922 addresses
+             may optionally be increased to three or four octets.
+*/
+
+static void
+fr_hdr_print(netdissect_options *ndo, int length, u_int addr_len,
+	     u_int dlci, uint32_t flags, uint16_t nlpid)
+{
+    if (ndo->ndo_qflag) {
+        ND_PRINT("Q.922, DLCI %u, length %u: ",
+                     dlci,
+                     length);
+    } else {
+        if (nlpid <= 0xff) /* if its smaller than 256 then its a NLPID */
+            ND_PRINT("Q.922, hdr-len %u, DLCI %u, Flags [%s], NLPID %s (0x%02x), length %u: ",
+                         addr_len,
+                         dlci,
+                         bittok2str(fr_header_flag_values, "none", flags),
+                         tok2str(nlpid_values,"unknown", nlpid),
+                         nlpid,
+                         length);
+        else /* must be an ethertype */
+            ND_PRINT("Q.922, hdr-len %u, DLCI %u, Flags [%s], cisco-ethertype %s (0x%04x), length %u: ",
+                         addr_len,
+                         dlci,
+                         bittok2str(fr_header_flag_values, "none", flags),
+                         tok2str(ethertype_values, "unknown", nlpid),
+                         nlpid,
+                         length);
+    }
+}
+
+/* Frame Relay */
+void
+fr_if_print(netdissect_options *ndo,
+            const struct pcap_pkthdr *h, const u_char *p)
+{
+	u_int length = h->len;
+	u_int caplen = h->caplen;
+
+	ndo->ndo_protocol = "fr";
+	if (caplen < 4) {	/* minimum frame header length */
+		nd_print_trunc(ndo);
+		ndo->ndo_ll_hdr_len += caplen;
+		return;
+	}
+
+	ndo->ndo_ll_hdr_len += fr_print(ndo, p, length);
+}
+
+u_int
+fr_print(netdissect_options *ndo,
+         const u_char *p, u_int length)
+{
+	int ret;
+	uint16_t extracted_ethertype;
+	u_int dlci;
+	u_int addr_len;
+	uint16_t nlpid;
+	u_int hdr_len;
+	uint32_t flags;
+
+	ndo->ndo_protocol = "fr";
+	ret = parse_q922_header(ndo, p, &dlci, &addr_len, &flags, length);
+	if (ret == -1)
+		goto trunc;
+	if (ret == 0) {
+		ND_PRINT("Q.922, invalid address");
+		return 0;
+	}
+
+	ND_TCHECK_1(p + addr_len);
+	if (length < addr_len + 1)
+		goto trunc;
+
+	if (GET_U_1(p + addr_len) != LLC_UI && dlci != 0) {
+                /*
+                 * Let's figure out if we have Cisco-style encapsulation,
+                 * with an Ethernet type (Cisco HDLC type?) following the
+                 * address.
+                 */
+		if (!ND_TTEST_2(p + addr_len) || length < addr_len + 2) {
+                        /* no Ethertype */
+                        ND_PRINT("UI %02x! ", GET_U_1(p + addr_len));
+                } else {
+                        extracted_ethertype = GET_BE_U_2(p + addr_len);
+
+                        if (ndo->ndo_eflag)
+                                fr_hdr_print(ndo, length, addr_len, dlci,
+                                    flags, extracted_ethertype);
+
+                        if (ethertype_print(ndo, extracted_ethertype,
+                                            p+addr_len+ETHERTYPE_LEN,
+                                            length-addr_len-ETHERTYPE_LEN,
+                                            ND_BYTES_AVAILABLE_AFTER(p)-addr_len-ETHERTYPE_LEN,
+                                            NULL, NULL) == 0)
+                                /* ether_type not known, probably it wasn't one */
+                                ND_PRINT("UI %02x! ", GET_U_1(p + addr_len));
+                        else
+                                return addr_len + 2;
+                }
+        }
+
+	ND_TCHECK_1(p + addr_len + 1);
+	if (length < addr_len + 2)
+		goto trunc;
+
+	if (GET_U_1(p + addr_len + 1) == 0) {
+		/*
+		 * Assume a pad byte after the control (UI) byte.
+		 * A pad byte should only be used with 3-byte Q.922.
+		 */
+		if (addr_len != 3)
+			ND_PRINT("Pad! ");
+		hdr_len = addr_len + 1 /* UI */ + 1 /* pad */ + 1 /* NLPID */;
+	} else {
+		/*
+		 * Not a pad byte.
+		 * A pad byte should be used with 3-byte Q.922.
+		 */
+		if (addr_len == 3)
+			ND_PRINT("No pad! ");
+		hdr_len = addr_len + 1 /* UI */ + 1 /* NLPID */;
+	}
+
+        ND_TCHECK_1(p + hdr_len - 1);
+	if (length < hdr_len)
+		goto trunc;
+	nlpid = GET_U_1(p + hdr_len - 1);
+
+	if (ndo->ndo_eflag)
+		fr_hdr_print(ndo, length, addr_len, dlci, flags, nlpid);
+	p += hdr_len;
+	length -= hdr_len;
+
+	switch (nlpid) {
+	case NLPID_IP:
+	        ip_print(ndo, p, length);
+		break;
+
+	case NLPID_IP6:
+		ip6_print(ndo, p, length);
+		break;
+
+	case NLPID_CLNP:
+	case NLPID_ESIS:
+	case NLPID_ISIS:
+		isoclns_print(ndo, p - 1, length + 1); /* OSI printers need the NLPID field */
+		break;
+
+	case NLPID_SNAP:
+		if (snap_print(ndo, p, length, ND_BYTES_AVAILABLE_AFTER(p), NULL, NULL, 0) == 0) {
+			/* ether_type not known, print raw packet */
+                        if (!ndo->ndo_eflag)
+                            fr_hdr_print(ndo, length + hdr_len, hdr_len,
+                                         dlci, flags, nlpid);
+			if (!ndo->ndo_suppress_default_print)
+				ND_DEFAULTPRINT(p - hdr_len, length + hdr_len);
+		}
+		break;
+
+        case NLPID_Q933:
+		q933_print(ndo, p, length);
+		break;
+
+        case NLPID_MFR:
+                frf15_print(ndo, p, length);
+                break;
+
+        case NLPID_PPP:
+                ppp_print(ndo, p, length);
+                break;
+
+	default:
+		if (!ndo->ndo_eflag)
+                    fr_hdr_print(ndo, length + hdr_len, addr_len,
+				     dlci, flags, nlpid);
+		if (!ndo->ndo_xflag)
+			ND_DEFAULTPRINT(p, length);
+	}
+
+	return hdr_len;
+
+trunc:
+        nd_print_trunc(ndo);
+        return 0;
+
+}
+
+/* Multi Link Frame Relay (FRF.16) */
+void
+mfr_if_print(netdissect_options *ndo,
+             const struct pcap_pkthdr *h, const u_char *p)
+{
+	u_int length = h->len;
+	u_int caplen = h->caplen;
+
+	ndo->ndo_protocol = "mfr";
+	if (caplen < 2) {	/* minimum frame header length */
+		nd_print_trunc(ndo);
+		ndo->ndo_ll_hdr_len += caplen;
+		return;
+	}
+
+	ndo->ndo_ll_hdr_len += mfr_print(ndo, p, length);
+}
+
+
+#define MFR_CTRL_MSG_ADD_LINK        1
+#define MFR_CTRL_MSG_ADD_LINK_ACK    2
+#define MFR_CTRL_MSG_ADD_LINK_REJ    3
+#define MFR_CTRL_MSG_HELLO           4
+#define MFR_CTRL_MSG_HELLO_ACK       5
+#define MFR_CTRL_MSG_REMOVE_LINK     6
+#define MFR_CTRL_MSG_REMOVE_LINK_ACK 7
+
+static const struct tok mfr_ctrl_msg_values[] = {
+    { MFR_CTRL_MSG_ADD_LINK, "Add Link" },
+    { MFR_CTRL_MSG_ADD_LINK_ACK, "Add Link ACK" },
+    { MFR_CTRL_MSG_ADD_LINK_REJ, "Add Link Reject" },
+    { MFR_CTRL_MSG_HELLO, "Hello" },
+    { MFR_CTRL_MSG_HELLO_ACK, "Hello ACK" },
+    { MFR_CTRL_MSG_REMOVE_LINK, "Remove Link" },
+    { MFR_CTRL_MSG_REMOVE_LINK_ACK, "Remove Link ACK" },
+    { 0, NULL }
+};
+
+#define MFR_CTRL_IE_BUNDLE_ID  1
+#define MFR_CTRL_IE_LINK_ID    2
+#define MFR_CTRL_IE_MAGIC_NUM  3
+#define MFR_CTRL_IE_TIMESTAMP  5
+#define MFR_CTRL_IE_VENDOR_EXT 6
+#define MFR_CTRL_IE_CAUSE      7
+
+static const struct tok mfr_ctrl_ie_values[] = {
+    { MFR_CTRL_IE_BUNDLE_ID, "Bundle ID"},
+    { MFR_CTRL_IE_LINK_ID, "Link ID"},
+    { MFR_CTRL_IE_MAGIC_NUM, "Magic Number"},
+    { MFR_CTRL_IE_TIMESTAMP, "Timestamp"},
+    { MFR_CTRL_IE_VENDOR_EXT, "Vendor Extension"},
+    { MFR_CTRL_IE_CAUSE, "Cause"},
+    { 0, NULL }
+};
+
+#define MFR_ID_STRING_MAXLEN 50
+
+struct ie_tlv_header_t {
+    uint8_t ie_type;
+    uint8_t ie_len;
+};
+
+u_int
+mfr_print(netdissect_options *ndo,
+          const u_char *p, u_int length)
+{
+    u_int tlen,idx,hdr_len = 0;
+    uint16_t sequence_num;
+    uint8_t ie_type,ie_len;
+    const uint8_t *tptr;
+
+
+/*
+ * FRF.16 Link Integrity Control Frame
+ *
+ *      7    6    5    4    3    2    1    0
+ *    +----+----+----+----+----+----+----+----+
+ *    | B  | E  | C=1| 0    0    0    0  | EA |
+ *    +----+----+----+----+----+----+----+----+
+ *    | 0    0    0    0    0    0    0    0  |
+ *    +----+----+----+----+----+----+----+----+
+ *    |              message type             |
+ *    +----+----+----+----+----+----+----+----+
+ */
+
+    ndo->ndo_protocol = "mfr";
+
+    if (length < 4) {	/* minimum frame header length */
+        ND_PRINT("[length %u < 4]", length);
+        nd_print_invalid(ndo);
+        return length;
+    }
+    ND_TCHECK_4(p);
+
+    if ((GET_U_1(p) & MFR_BEC_MASK) == MFR_CTRL_FRAME && GET_U_1(p + 1) == 0) {
+        ND_PRINT("FRF.16 Control, Flags [%s], %s, length %u",
+               bittok2str(frf_flag_values,"none",(GET_U_1(p) & MFR_BEC_MASK)),
+               tok2str(mfr_ctrl_msg_values,"Unknown Message (0x%02x)",GET_U_1(p + 2)),
+               length);
+        tptr = p + 3;
+        tlen = length -3;
+        hdr_len = 3;
+
+        if (!ndo->ndo_vflag)
+            return hdr_len;
+
+        while (tlen>sizeof(struct ie_tlv_header_t)) {
+            ND_TCHECK_LEN(tptr, sizeof(struct ie_tlv_header_t));
+            ie_type=GET_U_1(tptr);
+            ie_len=GET_U_1(tptr + 1);
+
+            ND_PRINT("\n\tIE %s (%u), length %u: ",
+                   tok2str(mfr_ctrl_ie_values,"Unknown",ie_type),
+                   ie_type,
+                   ie_len);
+
+            /* infinite loop check */
+            if (ie_type == 0 || ie_len <= sizeof(struct ie_tlv_header_t))
+                return hdr_len;
+
+            ND_TCHECK_LEN(tptr, ie_len);
+            tptr+=sizeof(struct ie_tlv_header_t);
+            /* tlv len includes header */
+            ie_len-=sizeof(struct ie_tlv_header_t);
+            tlen-=sizeof(struct ie_tlv_header_t);
+
+            switch (ie_type) {
+
+            case MFR_CTRL_IE_MAGIC_NUM:
+                /* FRF.16.1 Section 3.4.3 Magic Number Information Element */
+                if (ie_len != 4) {
+                    ND_PRINT("[IE data length %d != 4]", ie_len);
+                    nd_print_invalid(ndo);
+                    break;
+                }
+                ND_PRINT("0x%08x", GET_BE_U_4(tptr));
+                break;
+
+            case MFR_CTRL_IE_BUNDLE_ID: /* same message format */
+            case MFR_CTRL_IE_LINK_ID:
+                for (idx = 0; idx < ie_len && idx < MFR_ID_STRING_MAXLEN; idx++) {
+                    if (GET_U_1(tptr + idx) != 0) /* don't print null termination */
+                        fn_print_char(ndo, GET_U_1(tptr + idx));
+                    else
+                        break;
+                }
+                break;
+
+            case MFR_CTRL_IE_TIMESTAMP:
+                if (ie_len == sizeof(struct timeval)) {
+                    ts_print(ndo, (const struct timeval *)tptr);
+                    break;
+                }
+                /* fall through and hexdump if no unix timestamp */
+                ND_FALL_THROUGH;
+
+                /*
+                 * FIXME those are the defined IEs that lack a decoder
+                 * you are welcome to contribute code ;-)
+                 */
+
+            case MFR_CTRL_IE_VENDOR_EXT:
+            case MFR_CTRL_IE_CAUSE:
+
+            default:
+                if (ndo->ndo_vflag <= 1)
+                    print_unknown_data(ndo, tptr, "\n\t  ", ie_len);
+                break;
+            }
+
+            /* do we want to see a hexdump of the IE ? */
+            if (ndo->ndo_vflag > 1 )
+                print_unknown_data(ndo, tptr, "\n\t  ", ie_len);
+
+            tlen-=ie_len;
+            tptr+=ie_len;
+        }
+        return hdr_len;
+    }
+/*
+ * FRF.16 Fragmentation Frame
+ *
+ *      7    6    5    4    3    2    1    0
+ *    +----+----+----+----+----+----+----+----+
+ *    | B  | E  | C=0|seq. (high 4 bits) | EA |
+ *    +----+----+----+----+----+----+----+----+
+ *    |        sequence  (low 8 bits)         |
+ *    +----+----+----+----+----+----+----+----+
+ *    |        DLCI (6 bits)        | CR | EA |
+ *    +----+----+----+----+----+----+----+----+
+ *    |   DLCI (4 bits)   |FECN|BECN| DE | EA |
+ *    +----+----+----+----+----+----+----+----+
+ */
+
+    sequence_num = (GET_U_1(p)&0x1e)<<7 | GET_U_1(p + 1);
+    /* whole packet or first fragment ? */
+    if ((GET_U_1(p) & MFR_BEC_MASK) == MFR_FRAG_FRAME ||
+        (GET_U_1(p) & MFR_BEC_MASK) == MFR_B_BIT) {
+        ND_PRINT("FRF.16 Frag, seq %u, Flags [%s], ",
+               sequence_num,
+               bittok2str(frf_flag_values,"none",(GET_U_1(p) & MFR_BEC_MASK)));
+        hdr_len = 2;
+        fr_print(ndo, p+hdr_len,length-hdr_len);
+        return hdr_len;
+    }
+
+    /* must be a middle or the last fragment */
+    ND_PRINT("FRF.16 Frag, seq %u, Flags [%s]",
+           sequence_num,
+           bittok2str(frf_flag_values,"none",(GET_U_1(p) & MFR_BEC_MASK)));
+    print_unknown_data(ndo, p, "\n\t", length);
+
+    return hdr_len;
+
+trunc:
+    nd_print_trunc(ndo);
+    return length;
+}
+
+/* an NLPID of 0xb1 indicates a 2-byte
+ * FRF.15 header
+ *
+ *      7    6    5    4    3    2    1    0
+ *    +----+----+----+----+----+----+----+----+
+ *    ~              Q.922 header             ~
+ *    +----+----+----+----+----+----+----+----+
+ *    |             NLPID (8 bits)            | NLPID=0xb1
+ *    +----+----+----+----+----+----+----+----+
+ *    | B  | E  | C  |seq. (high 4 bits) | R  |
+ *    +----+----+----+----+----+----+----+----+
+ *    |        sequence  (low 8 bits)         |
+ *    +----+----+----+----+----+----+----+----+
+ */
+
+#define FR_FRF15_FRAGTYPE 0x01
+
+static void
+frf15_print(netdissect_options *ndo,
+            const u_char *p, u_int length)
+{
+    uint16_t sequence_num, flags;
+
+    if (length < 2)
+        goto trunc;
+
+    flags = GET_U_1(p)&MFR_BEC_MASK;
+    sequence_num = (GET_U_1(p)&0x1e)<<7 | GET_U_1(p + 1);
+
+    ND_PRINT("FRF.15, seq 0x%03x, Flags [%s],%s Fragmentation, length %u",
+           sequence_num,
+           bittok2str(frf_flag_values,"none",flags),
+           GET_U_1(p)&FR_FRF15_FRAGTYPE ? "Interface" : "End-to-End",
+           length);
+
+/* TODO:
+ * depending on all permutations of the B, E and C bit
+ * dig as deep as we can - e.g. on the first (B) fragment
+ * there is enough payload to print the IP header
+ * on non (B) fragments it depends if the fragmentation
+ * model is end-to-end or interface based whether we want to print
+ * another Q.922 header
+ */
+    return;
+
+trunc:
+    nd_print_trunc(ndo);
+}
+
+/*
+ * Q.933 decoding portion for framerelay specific.
+ */
+
+/* Q.933 packet format
+                      Format of Other Protocols
+                          using Q.933 NLPID
+                  +-------------------------------+
+                  |        Q.922 Address          |
+                  +---------------+---------------+
+                  |Control  0x03  | NLPID   0x08  |
+                  +---------------+---------------+
+                  |          L2 Protocol ID       |
+                  | octet 1       |  octet 2      |
+                  +-------------------------------+
+                  |          L3 Protocol ID       |
+                  | octet 2       |  octet 2      |
+                  +-------------------------------+
+                  |         Protocol Data         |
+                  +-------------------------------+
+                  | FCS                           |
+                  +-------------------------------+
+ */
+
+/* L2 (Octet 1)- Call Reference Usually is 0x0 */
+
+/*
+ * L2 (Octet 2)- Message Types definition 1 byte long.
+ */
+/* Call Establish */
+#define MSG_TYPE_ESC_TO_NATIONAL  0x00
+#define MSG_TYPE_ALERT            0x01
+#define MSG_TYPE_CALL_PROCEEDING  0x02
+#define MSG_TYPE_CONNECT          0x07
+#define MSG_TYPE_CONNECT_ACK      0x0F
+#define MSG_TYPE_PROGRESS         0x03
+#define MSG_TYPE_SETUP            0x05
+/* Call Clear */
+#define MSG_TYPE_DISCONNECT       0x45
+#define MSG_TYPE_RELEASE          0x4D
+#define MSG_TYPE_RELEASE_COMPLETE 0x5A
+#define MSG_TYPE_RESTART          0x46
+#define MSG_TYPE_RESTART_ACK      0x4E
+/* Status */
+#define MSG_TYPE_STATUS           0x7D
+#define MSG_TYPE_STATUS_ENQ       0x75
+
+static const struct tok fr_q933_msg_values[] = {
+    { MSG_TYPE_ESC_TO_NATIONAL, "ESC to National" },
+    { MSG_TYPE_ALERT, "Alert" },
+    { MSG_TYPE_CALL_PROCEEDING, "Call proceeding" },
+    { MSG_TYPE_CONNECT, "Connect" },
+    { MSG_TYPE_CONNECT_ACK, "Connect ACK" },
+    { MSG_TYPE_PROGRESS, "Progress" },
+    { MSG_TYPE_SETUP, "Setup" },
+    { MSG_TYPE_DISCONNECT, "Disconnect" },
+    { MSG_TYPE_RELEASE, "Release" },
+    { MSG_TYPE_RELEASE_COMPLETE, "Release Complete" },
+    { MSG_TYPE_RESTART, "Restart" },
+    { MSG_TYPE_RESTART_ACK, "Restart ACK" },
+    { MSG_TYPE_STATUS, "Status Reply" },
+    { MSG_TYPE_STATUS_ENQ, "Status Enquiry" },
+    { 0, NULL }
+};
+
+#define IE_IS_SINGLE_OCTET(iecode)	((iecode) & 0x80)
+#define IE_IS_SHIFT(iecode)		(((iecode) & 0xF0) == 0x90)
+#define IE_SHIFT_IS_NON_LOCKING(iecode)	((iecode) & 0x08)
+#define IE_SHIFT_IS_LOCKING(iecode)	(!(IE_SHIFT_IS_NON_LOCKING(iecode)))
+#define IE_SHIFT_CODESET(iecode)	((iecode) & 0x07)
+
+#define FR_LMI_ANSI_REPORT_TYPE_IE	0x01
+#define FR_LMI_ANSI_LINK_VERIFY_IE_91	0x19 /* details? */
+#define FR_LMI_ANSI_LINK_VERIFY_IE	0x03
+#define FR_LMI_ANSI_PVC_STATUS_IE	0x07
+
+#define FR_LMI_CCITT_REPORT_TYPE_IE	0x51
+#define FR_LMI_CCITT_LINK_VERIFY_IE	0x53
+#define FR_LMI_CCITT_PVC_STATUS_IE	0x57
+
+static const struct tok fr_q933_ie_values_codeset_0_5[] = {
+    { FR_LMI_ANSI_REPORT_TYPE_IE, "ANSI Report Type" },
+    { FR_LMI_ANSI_LINK_VERIFY_IE_91, "ANSI Link Verify" },
+    { FR_LMI_ANSI_LINK_VERIFY_IE, "ANSI Link Verify" },
+    { FR_LMI_ANSI_PVC_STATUS_IE, "ANSI PVC Status" },
+    { FR_LMI_CCITT_REPORT_TYPE_IE, "CCITT Report Type" },
+    { FR_LMI_CCITT_LINK_VERIFY_IE, "CCITT Link Verify" },
+    { FR_LMI_CCITT_PVC_STATUS_IE, "CCITT PVC Status" },
+    { 0, NULL }
+};
+
+#define FR_LMI_REPORT_TYPE_IE_FULL_STATUS 0
+#define FR_LMI_REPORT_TYPE_IE_LINK_VERIFY 1
+#define FR_LMI_REPORT_TYPE_IE_ASYNC_PVC   2
+
+static const struct tok fr_lmi_report_type_ie_values[] = {
+    { FR_LMI_REPORT_TYPE_IE_FULL_STATUS, "Full Status" },
+    { FR_LMI_REPORT_TYPE_IE_LINK_VERIFY, "Link verify" },
+    { FR_LMI_REPORT_TYPE_IE_ASYNC_PVC, "Async PVC Status" },
+    { 0, NULL }
+};
+
+/* array of 16 codesets - currently we only support codepage 0 and 5 */
+static const struct tok *fr_q933_ie_codesets[] = {
+    fr_q933_ie_values_codeset_0_5,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    fr_q933_ie_values_codeset_0_5,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL
+};
+
+static int fr_q933_print_ie_codeset_0_5(netdissect_options *ndo, u_int iecode,
+    u_int ielength, const u_char *p);
+
+typedef int (*codeset_pr_func_t)(netdissect_options *, u_int iecode,
+    u_int ielength, const u_char *p);
+
+/* array of 16 codesets - currently we only support codepage 0 and 5 */
+static const codeset_pr_func_t fr_q933_print_ie_codeset[] = {
+    fr_q933_print_ie_codeset_0_5,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    fr_q933_print_ie_codeset_0_5,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL
+};
+
+/*
+ * ITU-T Q.933.
+ *
+ * p points to octet 2, the octet containing the length of the
+ * call reference value, so p[n] is octet n+2 ("octet X" is as
+ * used in Q.931/Q.933).
+ *
+ * XXX - actually used both for Q.931 and Q.933.
+ */
+void
+q933_print(netdissect_options *ndo,
+           const u_char *p, u_int length)
+{
+	u_int olen;
+	u_int call_ref_length, i;
+	uint8_t call_ref[15];	/* maximum length - length field is 4 bits */
+	u_int msgtype;
+	u_int iecode;
+	u_int ielength;
+	u_int codeset = 0;
+	u_int is_ansi = 0;
+	u_int ie_is_known;
+	u_int non_locking_shift;
+	u_int unshift_codeset;
+
+	ndo->ndo_protocol = "q.933";
+	ND_PRINT("%s", ndo->ndo_eflag ? "" : "Q.933");
+
+	if (length == 0 || !ND_TTEST_1(p)) {
+		if (!ndo->ndo_eflag)
+			ND_PRINT(", ");
+		ND_PRINT("length %u", length);
+		goto trunc;
+	}
+
+	/*
+	 * Get the length of the call reference value.
+	 */
+	olen = length; /* preserve the original length for display */
+	call_ref_length = GET_U_1(p) & 0x0f;
+	p++;
+	length--;
+
+	/*
+	 * Get the call reference value.
+	 */
+	for (i = 0; i < call_ref_length; i++) {
+		if (length == 0 || !ND_TTEST_1(p)) {
+			if (!ndo->ndo_eflag)
+				ND_PRINT(", ");
+			ND_PRINT("length %u", olen);
+			goto trunc;
+		}
+		call_ref[i] = GET_U_1(p);
+		p++;
+		length--;
+	}
+
+	/*
+	 * Get the message type.
+	 */
+	if (length == 0 || !ND_TTEST_1(p)) {
+		if (!ndo->ndo_eflag)
+			ND_PRINT(", ");
+		ND_PRINT("length %u", olen);
+		goto trunc;
+	}
+	msgtype = GET_U_1(p);
+	p++;
+	length--;
+
+	/*
+	 * Peek ahead to see if we start with a shift.
+	 */
+	non_locking_shift = 0;
+	unshift_codeset = codeset;
+	if (length != 0) {
+		if (!ND_TTEST_1(p)) {
+			if (!ndo->ndo_eflag)
+				ND_PRINT(", ");
+			ND_PRINT("length %u", olen);
+			goto trunc;
+		}
+		iecode = GET_U_1(p);
+		if (IE_IS_SHIFT(iecode)) {
+			/*
+			 * It's a shift.  Skip over it.
+			 */
+			p++;
+			length--;
+
+			/*
+			 * Get the codeset.
+			 */
+			codeset = IE_SHIFT_CODESET(iecode);
+
+			/*
+			 * If it's a locking shift to codeset 5,
+			 * mark this as ANSI.  (XXX - 5 is actually
+			 * for national variants in general, not
+			 * the US variant in particular, but maybe
+			 * this is more American exceptionalism. :-))
+			 */
+			if (IE_SHIFT_IS_LOCKING(iecode)) {
+				/*
+				 * It's a locking shift.
+				 */
+				if (codeset == 5) {
+					/*
+					 * It's a locking shift to
+					 * codeset 5, so this is
+					 * T1.617 Annex D.
+					 */
+					is_ansi = 1;
+				}
+			} else {
+				/*
+				 * It's a non-locking shift.
+				 * Remember the current codeset, so we
+				 * can revert to it after the next IE.
+				 */
+				non_locking_shift = 1;
+				unshift_codeset = 0;
+			}
+		}
+	}
+
+	/* printing out header part */
+	if (!ndo->ndo_eflag)
+		ND_PRINT(", ");
+	ND_PRINT("%s, codeset %u", is_ansi ? "ANSI" : "CCITT", codeset);
+
+	if (call_ref_length != 0) {
+		if (call_ref_length > 1 || GET_U_1(p) != 0) {
+			/*
+			 * Not a dummy call reference.
+			 */
+			ND_PRINT(", Call Ref: 0x");
+			for (i = 0; i < call_ref_length; i++)
+				ND_PRINT("%02x", call_ref[i]);
+		}
+	}
+	if (ndo->ndo_vflag) {
+		ND_PRINT(", %s (0x%02x), length %u",
+		   tok2str(fr_q933_msg_values,
+			"unknown message", msgtype),
+		   msgtype,
+		   olen);
+	} else {
+		ND_PRINT(", %s",
+		       tok2str(fr_q933_msg_values,
+			       "unknown message 0x%02x", msgtype));
+	}
+
+	/* Loop through the rest of the IEs */
+	while (length != 0) {
+		/*
+		 * What's the state of any non-locking shifts?
+		 */
+		if (non_locking_shift == 1) {
+			/*
+			 * There's a non-locking shift in effect for
+			 * this IE.  Count it, so we reset the codeset
+			 * before the next IE.
+			 */
+			non_locking_shift = 2;
+		} else if (non_locking_shift == 2) {
+			/*
+			 * Unshift.
+			 */
+			codeset = unshift_codeset;
+			non_locking_shift = 0;
+		}
+
+		/*
+		 * Get the first octet of the IE.
+		 */
+		if (!ND_TTEST_1(p)) {
+			if (!ndo->ndo_vflag) {
+				ND_PRINT(", length %u", olen);
+			}
+			goto trunc;
+		}
+		iecode = GET_U_1(p);
+		p++;
+		length--;
+
+		/* Single-octet IE? */
+		if (IE_IS_SINGLE_OCTET(iecode)) {
+			/*
+			 * Yes.  Is it a shift?
+			 */
+			if (IE_IS_SHIFT(iecode)) {
+				/*
+				 * Yes.  Is it locking?
+				 */
+				if (IE_SHIFT_IS_LOCKING(iecode)) {
+					/*
+					 * Yes.
+					 */
+					non_locking_shift = 0;
+				} else {
+					/*
+					 * No.  Remember the current
+					 * codeset, so we can revert
+					 * to it after the next IE.
+					 */
+					non_locking_shift = 1;
+					unshift_codeset = codeset;
+				}
+
+				/*
+				 * Get the codeset.
+				 */
+				codeset = IE_SHIFT_CODESET(iecode);
+			}
+		} else {
+			/*
+			 * No.  Get the IE length.
+			 */
+			if (length == 0 || !ND_TTEST_1(p)) {
+				if (!ndo->ndo_vflag) {
+					ND_PRINT(", length %u", olen);
+				}
+				goto trunc;
+			}
+			ielength = GET_U_1(p);
+			p++;
+			length--;
+
+			/* lets do the full IE parsing only in verbose mode
+			 * however some IEs (DLCI Status, Link Verify)
+			 * are also interesting in non-verbose mode */
+			if (ndo->ndo_vflag) {
+				ND_PRINT("\n\t%s IE (0x%02x), length %u: ",
+				    tok2str(fr_q933_ie_codesets[codeset],
+					"unknown", iecode),
+				    iecode,
+				    ielength);
+			}
+
+			/* sanity checks */
+			if (iecode == 0 || ielength == 0) {
+				return;
+			}
+			if (length < ielength || !ND_TTEST_LEN(p, ielength)) {
+				if (!ndo->ndo_vflag) {
+					ND_PRINT(", length %u", olen);
+				}
+				goto trunc;
+			}
+
+			ie_is_known = 0;
+			if (fr_q933_print_ie_codeset[codeset] != NULL) {
+				ie_is_known = fr_q933_print_ie_codeset[codeset](ndo, iecode, ielength, p);
+			}
+
+			if (ie_is_known) {
+				/*
+				 * Known IE; do we want to see a hexdump
+				 * of it?
+				 */
+				if (ndo->ndo_vflag > 1) {
+					/* Yes. */
+					print_unknown_data(ndo, p, "\n\t  ", ielength);
+				}
+			} else {
+				/*
+				 * Unknown IE; if we're printing verbosely,
+				 * print its content in hex.
+				 */
+				if (ndo->ndo_vflag >= 1) {
+					print_unknown_data(ndo, p, "\n\t", ielength);
+				}
+			}
+
+			length -= ielength;
+			p += ielength;
+		}
+	}
+	if (!ndo->ndo_vflag) {
+	    ND_PRINT(", length %u", olen);
+	}
+	return;
+
+trunc:
+	nd_print_trunc(ndo);
+}
+
+static int
+fr_q933_print_ie_codeset_0_5(netdissect_options *ndo, u_int iecode,
+                          u_int ielength, const u_char *p)
+{
+        u_int dlci;
+
+        switch (iecode) {
+
+        case FR_LMI_ANSI_REPORT_TYPE_IE: /* fall through */
+        case FR_LMI_CCITT_REPORT_TYPE_IE:
+            if (ielength < 1) {
+                if (!ndo->ndo_vflag) {
+                    ND_PRINT(", ");
+	        }
+                ND_PRINT("Invalid REPORT TYPE IE");
+                return 1;
+            }
+            if (ndo->ndo_vflag) {
+                ND_PRINT("%s (%u)",
+                       tok2str(fr_lmi_report_type_ie_values,"unknown",GET_U_1(p)),
+                       GET_U_1(p));
+	    }
+            return 1;
+
+        case FR_LMI_ANSI_LINK_VERIFY_IE: /* fall through */
+        case FR_LMI_CCITT_LINK_VERIFY_IE:
+        case FR_LMI_ANSI_LINK_VERIFY_IE_91:
+            if (!ndo->ndo_vflag) {
+                ND_PRINT(", ");
+	    }
+            if (ielength < 2) {
+                ND_PRINT("Invalid LINK VERIFY IE");
+                return 1;
+            }
+            ND_PRINT("TX Seq: %3d, RX Seq: %3d", GET_U_1(p), GET_U_1(p + 1));
+            return 1;
+
+        case FR_LMI_ANSI_PVC_STATUS_IE: /* fall through */
+        case FR_LMI_CCITT_PVC_STATUS_IE:
+            if (!ndo->ndo_vflag) {
+                ND_PRINT(", ");
+	    }
+            /* now parse the DLCI information element. */
+            if ((ielength < 3) ||
+                (GET_U_1(p) & 0x80) ||
+                ((ielength == 3) && !(GET_U_1(p + 1) & 0x80)) ||
+                ((ielength == 4) &&
+                  ((GET_U_1(p + 1) & 0x80) || !(GET_U_1(p + 2) & 0x80))) ||
+                ((ielength == 5) &&
+                  ((GET_U_1(p + 1) & 0x80) || (GET_U_1(p + 2) & 0x80) ||
+                   !(GET_U_1(p + 3) & 0x80))) ||
+                (ielength > 5) ||
+                !(GET_U_1(p + ielength - 1) & 0x80)) {
+                ND_PRINT("Invalid DLCI in PVC STATUS IE");
+                return 1;
+	    }
+
+            dlci = ((GET_U_1(p) & 0x3F) << 4) | ((GET_U_1(p + 1) & 0x78) >> 3);
+            if (ielength == 4) {
+                dlci = (dlci << 6) | ((GET_U_1(p + 2) & 0x7E) >> 1);
+	    }
+            else if (ielength == 5) {
+                dlci = (dlci << 13) | (GET_U_1(p + 2) & 0x7F) | ((GET_U_1(p + 3) & 0x7E) >> 1);
+	    }
+
+            ND_PRINT("DLCI %u: status %s%s", dlci,
+                    GET_U_1(p + ielength - 1) & 0x8 ? "New, " : "",
+                    GET_U_1(p + ielength - 1) & 0x2 ? "Active" : "Inactive");
+            return 1;
+	}
+
+        return 0;
+}