| /* |
| * 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("DLCI xxxxxxxxxx")]; |
| memset(buffer, 0, sizeof(buffer)); |
| |
| if (parse_q922_header(ndo, p, &dlci, &addr_len, &flags, length) == 1){ |
| snprintf(buffer, sizeof(buffer), "DLCI %u", dlci); |
| } |
| |
| 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; |
| } |
