| /* |
| * Copyright (c) 2007-2011 Grégoire Henry, Juliusz Chroboczek |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. Neither the name of the project 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 BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| */ |
| |
| #ifdef HAVE_CONFIG_H |
| #include "config.h" |
| #endif |
| |
| #include <tcpdump-stdinc.h> |
| |
| #include <stdio.h> |
| #include <string.h> |
| |
| #include "addrtoname.h" |
| #include "interface.h" |
| #include "extract.h" |
| |
| static void babel_print_v2(const u_char *cp, u_int length); |
| |
| void |
| babel_print(const u_char *cp, u_int length) { |
| printf("babel"); |
| |
| TCHECK2(*cp, 4); |
| |
| if(cp[0] != 42) { |
| printf(" malformed header"); |
| return; |
| } else { |
| printf(" %d", cp[1]); |
| } |
| |
| switch(cp[1]) { |
| case 2: |
| babel_print_v2(cp,length); |
| break; |
| default: |
| printf(" unknown version"); |
| break; |
| } |
| |
| return; |
| |
| trunc: |
| printf(" [|babel]"); |
| return; |
| } |
| |
| /* TLVs */ |
| #define MESSAGE_PAD1 0 |
| #define MESSAGE_PADN 1 |
| #define MESSAGE_ACK_REQ 2 |
| #define MESSAGE_ACK 3 |
| #define MESSAGE_HELLO 4 |
| #define MESSAGE_IHU 5 |
| #define MESSAGE_ROUTER_ID 6 |
| #define MESSAGE_NH 7 |
| #define MESSAGE_UPDATE 8 |
| #define MESSAGE_REQUEST 9 |
| #define MESSAGE_MH_REQUEST 10 |
| #define MESSAGE_TSPC 11 |
| #define MESSAGE_HMAC 12 |
| |
| /* sub-TLVs */ |
| #define MESSAGE_SUB_PAD1 0 |
| #define MESSAGE_SUB_PADN 1 |
| #define MESSAGE_SUB_DIVERSITY 2 |
| |
| /* Diversity sub-TLV channel codes */ |
| static const struct tok diversity_str[] = { |
| { 0, "reserved" }, |
| { 255, "all" }, |
| { 0, NULL } |
| }; |
| |
| static const char * |
| format_id(const u_char *id) |
| { |
| static char buf[25]; |
| snprintf(buf, 25, "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x", |
| id[0], id[1], id[2], id[3], id[4], id[5], id[6], id[7]); |
| buf[24] = '\0'; |
| return buf; |
| } |
| |
| static const unsigned char v4prefix[16] = |
| {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF, 0, 0, 0, 0 }; |
| |
| static const char * |
| format_prefix(const u_char *prefix, unsigned char plen) |
| { |
| static char buf[50]; |
| if(plen >= 96 && memcmp(prefix, v4prefix, 12) == 0) |
| snprintf(buf, 50, "%s/%u", ipaddr_string(prefix + 12), plen - 96); |
| else |
| #ifdef INET6 |
| snprintf(buf, 50, "%s/%u", ip6addr_string(prefix), plen); |
| #else |
| snprintf(buf, 50, "IPv6 addresses not supported"); |
| #endif |
| buf[49] = '\0'; |
| return buf; |
| } |
| |
| static const char * |
| format_address(const u_char *prefix) |
| { |
| if(memcmp(prefix, v4prefix, 12) == 0) |
| return ipaddr_string(prefix + 12); |
| else |
| #ifdef INET6 |
| return ip6addr_string(prefix); |
| #else |
| return "IPv6 addresses not supported"; |
| #endif |
| } |
| |
| static const char * |
| format_interval(const u_int16_t i) |
| { |
| static char buf[sizeof("0000.0s")]; |
| |
| if (i == 0) |
| return "0.0s (bogus)"; |
| snprintf(buf, sizeof(buf), "%u.%us", i / 10, i % 10); |
| return buf; |
| } |
| |
| static const char * |
| format_interval_update(const u_int16_t i) |
| { |
| return i == 0xFFFF ? "infinity" : format_interval(i); |
| } |
| |
| /* Return number of octets consumed from the input buffer (not the prefix length |
| * in bytes), or -1 for encoding error. */ |
| static int |
| network_prefix(int ae, int plen, unsigned int omitted, |
| const unsigned char *p, const unsigned char *dp, |
| unsigned int len, unsigned char *p_r) |
| { |
| unsigned pb; |
| unsigned char prefix[16]; |
| int consumed = 0; |
| |
| if(plen >= 0) |
| pb = (plen + 7) / 8; |
| else if(ae == 1) |
| pb = 4; |
| else |
| pb = 16; |
| |
| if(pb > 16) |
| return -1; |
| |
| memset(prefix, 0, 16); |
| |
| switch(ae) { |
| case 0: break; |
| case 1: |
| if(omitted > 4 || pb > 4 || (pb > omitted && len < pb - omitted)) |
| return -1; |
| memcpy(prefix, v4prefix, 12); |
| if(omitted) { |
| if (dp == NULL) return -1; |
| memcpy(prefix, dp, 12 + omitted); |
| } |
| if(pb > omitted) { |
| memcpy(prefix + 12 + omitted, p, pb - omitted); |
| consumed = pb - omitted; |
| } |
| break; |
| case 2: |
| if(omitted > 16 || (pb > omitted && len < pb - omitted)) |
| return -1; |
| if(omitted) { |
| if (dp == NULL) return -1; |
| memcpy(prefix, dp, omitted); |
| } |
| if(pb > omitted) { |
| memcpy(prefix + omitted, p, pb - omitted); |
| consumed = pb - omitted; |
| } |
| break; |
| case 3: |
| if(pb > 8 && len < pb - 8) return -1; |
| prefix[0] = 0xfe; |
| prefix[1] = 0x80; |
| if(pb > 8) { |
| memcpy(prefix + 8, p, pb - 8); |
| consumed = pb - 8; |
| } |
| break; |
| default: |
| return -1; |
| } |
| |
| memcpy(p_r, prefix, 16); |
| return consumed; |
| } |
| |
| static int |
| network_address(int ae, const unsigned char *a, unsigned int len, |
| unsigned char *a_r) |
| { |
| return network_prefix(ae, -1, 0, a, NULL, len, a_r); |
| } |
| |
| /* |
| * Sub-TLVs consume the "extra data" of Babel TLVs (see Section 4.3 of RFC6126), |
| * their encoding is similar to the encoding of TLVs, but the type namespace is |
| * different: |
| * |
| * o Type 0 stands for Pad1 sub-TLV with the same encoding as the Pad1 TLV. |
| * o Type 1 stands for PadN sub-TLV with the same encoding as the PadN TLV. |
| * o Type 2 stands for Diversity sub-TLV, which propagates diversity routing |
| * data. Its body is a variable-length sequence of 8-bit unsigned integers, |
| * each representing per-hop number of interferring radio channel for the |
| * prefix. Channel 0 is invalid and must not be used in the sub-TLV, channel |
| * 255 interferes with any other channel. |
| * |
| * Sub-TLV types 0 and 1 are valid for any TLV type, whether sub-TLV type 2 is |
| * only valid for TLV type 8 (Update). Note that within an Update TLV a missing |
| * Diversity sub-TLV is not the same as a Diversity sub-TLV with an empty body. |
| * The former would mean a lack of any claims about the interference, and the |
| * latter would state that interference is definitely absent. */ |
| static void |
| subtlvs_print(const u_char *cp, const u_char *ep, const uint8_t tlv_type) { |
| uint8_t subtype, sublen; |
| const char *sep; |
| |
| while (cp < ep) { |
| subtype = *cp++; |
| if(subtype == MESSAGE_SUB_PAD1) { |
| printf(" sub-pad1"); |
| continue; |
| } |
| if(cp == ep) |
| goto corrupt; |
| sublen = *cp++; |
| if(cp + sublen > ep) |
| goto corrupt; |
| |
| switch(subtype) { |
| case MESSAGE_SUB_PADN: |
| printf(" sub-padn"); |
| cp += sublen; |
| break; |
| case MESSAGE_SUB_DIVERSITY: |
| printf(" sub-diversity"); |
| if (sublen == 0) { |
| printf(" empty"); |
| break; |
| } |
| sep = " "; |
| while(sublen--) { |
| printf("%s%s", sep, tok2str(diversity_str, "%u", *cp++)); |
| sep = "-"; |
| } |
| if(tlv_type != MESSAGE_UPDATE) |
| printf(" (bogus)"); |
| break; |
| default: |
| printf(" sub-unknown-0x%02x", subtype); |
| cp += sublen; |
| } /* switch */ |
| } /* while */ |
| return; |
| |
| corrupt: |
| printf(" (corrupt)"); |
| } |
| |
| #define ICHECK(i, l) \ |
| if ((i) + (l) > bodylen || (i) + (l) > length) goto corrupt; |
| |
| static void |
| babel_print_v2(const u_char *cp, u_int length) { |
| u_int i; |
| u_short bodylen; |
| u_char v4_prefix[16] = |
| {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF, 0, 0, 0, 0 }; |
| u_char v6_prefix[16] = {0}; |
| |
| TCHECK2(*cp, 4); |
| if (length < 4) |
| goto corrupt; |
| bodylen = EXTRACT_16BITS(cp + 2); |
| printf(" (%u)", bodylen); |
| |
| /* Process the TLVs in the body */ |
| i = 0; |
| while(i < bodylen) { |
| const u_char *message; |
| u_int type, len; |
| |
| message = cp + 4 + i; |
| |
| TCHECK2(*message, 1); |
| if((type = message[0]) == MESSAGE_PAD1) { |
| printf(vflag ? "\n\tPad 1" : " pad1"); |
| i += 1; |
| continue; |
| } |
| |
| TCHECK2(*message, 2); |
| ICHECK(i, 2); |
| len = message[1]; |
| |
| TCHECK2(*message, 2 + len); |
| ICHECK(i, 2 + len); |
| |
| switch(type) { |
| case MESSAGE_PADN: { |
| if(!vflag) |
| printf(" padN"); |
| else |
| printf("\n\tPad %d", len + 2); |
| } |
| break; |
| |
| case MESSAGE_ACK_REQ: { |
| u_short nonce, interval; |
| if(!vflag) |
| printf(" ack-req"); |
| else { |
| printf("\n\tAcknowledgment Request "); |
| if(len < 6) goto corrupt; |
| nonce = EXTRACT_16BITS(message + 4); |
| interval = EXTRACT_16BITS(message + 6); |
| printf("%04x %s", nonce, format_interval(interval)); |
| } |
| } |
| break; |
| |
| case MESSAGE_ACK: { |
| u_short nonce; |
| if(!vflag) |
| printf(" ack"); |
| else { |
| printf("\n\tAcknowledgment "); |
| if(len < 2) goto corrupt; |
| nonce = EXTRACT_16BITS(message + 2); |
| printf("%04x", nonce); |
| } |
| } |
| break; |
| |
| case MESSAGE_HELLO: { |
| u_short seqno, interval; |
| if(!vflag) |
| printf(" hello"); |
| else { |
| printf("\n\tHello "); |
| if(len < 6) goto corrupt; |
| seqno = EXTRACT_16BITS(message + 4); |
| interval = EXTRACT_16BITS(message + 6); |
| printf("seqno %u interval %s", seqno, format_interval(interval)); |
| } |
| } |
| break; |
| |
| case MESSAGE_IHU: { |
| unsigned short txcost, interval; |
| if(!vflag) |
| printf(" ihu"); |
| else { |
| u_char address[16]; |
| int rc; |
| printf("\n\tIHU "); |
| if(len < 6) goto corrupt; |
| txcost = EXTRACT_16BITS(message + 4); |
| interval = EXTRACT_16BITS(message + 6); |
| rc = network_address(message[2], message + 8, len - 6, address); |
| if(rc < 0) { printf("[|babel]"); break; } |
| printf("%s txcost %u interval %s", |
| format_address(address), txcost, format_interval(interval)); |
| } |
| } |
| break; |
| |
| case MESSAGE_ROUTER_ID: { |
| if(!vflag) |
| printf(" router-id"); |
| else { |
| printf("\n\tRouter Id"); |
| if(len < 10) goto corrupt; |
| printf(" %s", format_id(message + 4)); |
| } |
| } |
| break; |
| |
| case MESSAGE_NH: { |
| if(!vflag) |
| printf(" nh"); |
| else { |
| int rc; |
| u_char nh[16]; |
| printf("\n\tNext Hop"); |
| if(len < 2) goto corrupt; |
| rc = network_address(message[2], message + 4, len - 2, nh); |
| if(rc < 0) goto corrupt; |
| printf(" %s", format_address(nh)); |
| } |
| } |
| break; |
| |
| case MESSAGE_UPDATE: { |
| if(!vflag) { |
| printf(" update"); |
| if(len < 1) |
| printf("/truncated"); |
| else |
| printf("%s%s%s", |
| (message[3] & 0x80) ? "/prefix": "", |
| (message[3] & 0x40) ? "/id" : "", |
| (message[3] & 0x3f) ? "/unknown" : ""); |
| } else { |
| u_short interval, seqno, metric; |
| u_char plen; |
| int rc; |
| u_char prefix[16]; |
| printf("\n\tUpdate"); |
| if(len < 10) goto corrupt; |
| plen = message[4] + (message[2] == 1 ? 96 : 0); |
| rc = network_prefix(message[2], message[4], message[5], |
| message + 12, |
| message[2] == 1 ? v4_prefix : v6_prefix, |
| len - 10, prefix); |
| if(rc < 0) goto corrupt; |
| interval = EXTRACT_16BITS(message + 6); |
| seqno = EXTRACT_16BITS(message + 8); |
| metric = EXTRACT_16BITS(message + 10); |
| printf("%s%s%s %s metric %u seqno %u interval %s", |
| (message[3] & 0x80) ? "/prefix": "", |
| (message[3] & 0x40) ? "/id" : "", |
| (message[3] & 0x3f) ? "/unknown" : "", |
| format_prefix(prefix, plen), |
| metric, seqno, format_interval_update(interval)); |
| if(message[3] & 0x80) { |
| if(message[2] == 1) |
| memcpy(v4_prefix, prefix, 16); |
| else |
| memcpy(v6_prefix, prefix, 16); |
| } |
| /* extra data? */ |
| if((u_int)rc < len - 10) |
| subtlvs_print(message + 12 + rc, message + 2 + len, type); |
| } |
| } |
| break; |
| |
| case MESSAGE_REQUEST: { |
| if(!vflag) |
| printf(" request"); |
| else { |
| int rc; |
| u_char prefix[16], plen; |
| printf("\n\tRequest "); |
| if(len < 2) goto corrupt; |
| plen = message[3] + (message[2] == 1 ? 96 : 0); |
| rc = network_prefix(message[2], message[3], 0, |
| message + 4, NULL, len - 2, prefix); |
| if(rc < 0) goto corrupt; |
| plen = message[3] + (message[2] == 1 ? 96 : 0); |
| printf("for %s", |
| message[2] == 0 ? "any" : format_prefix(prefix, plen)); |
| } |
| } |
| break; |
| |
| case MESSAGE_MH_REQUEST : { |
| if(!vflag) |
| printf(" mh-request"); |
| else { |
| int rc; |
| u_short seqno; |
| u_char prefix[16], plen; |
| printf("\n\tMH-Request "); |
| if(len < 14) goto corrupt; |
| seqno = EXTRACT_16BITS(message + 4); |
| rc = network_prefix(message[2], message[3], 0, |
| message + 16, NULL, len - 14, prefix); |
| if(rc < 0) goto corrupt; |
| plen = message[3] + (message[2] == 1 ? 96 : 0); |
| printf("(%u hops) for %s seqno %u id %s", |
| message[6], format_prefix(prefix, plen), |
| seqno, format_id(message + 8)); |
| } |
| } |
| break; |
| case MESSAGE_TSPC : |
| if(!vflag) |
| printf(" tspc"); |
| else { |
| printf("\n\tTS/PC "); |
| if(len < 6) goto corrupt; |
| printf("timestamp %u packetcounter %u", EXTRACT_32BITS (message + 4), |
| EXTRACT_16BITS(message + 2)); |
| } |
| break; |
| case MESSAGE_HMAC : { |
| if(!vflag) |
| printf(" hmac"); |
| else { |
| unsigned j; |
| printf("\n\tHMAC "); |
| if(len < 18) goto corrupt; |
| printf("key-id %u digest-%u ", EXTRACT_16BITS(message + 2), len - 2); |
| for (j = 0; j < len - 2; j++) |
| printf ("%02X", message[4 + j]); |
| } |
| } |
| break; |
| default: |
| if(!vflag) |
| printf(" unknown"); |
| else |
| printf("\n\tUnknown message type %d", type); |
| } |
| i += len + 2; |
| } |
| return; |
| |
| trunc: |
| printf(" [|babel]"); |
| return; |
| |
| corrupt: |
| printf(" (corrupt)"); |
| return; |
| } |
