/* * 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; }