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Diffstat (limited to 'print-babel.c')
| -rw-r--r-- | print-babel.c | 863 |
1 files changed, 863 insertions, 0 deletions
diff --git a/print-babel.c b/print-babel.c new file mode 100644 index 0000000..d802a72 --- /dev/null +++ b/print-babel.c @@ -0,0 +1,863 @@ +/* + * 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. + */ + +/* \summary: Babel Routing Protocol printer */ +/* Specifications: + * + * RFC 6126 + * RFC 7298 + * RFC 7557 + * draft-ietf-babel-rfc6126bis-17 + * draft-ietf-babel-hmac-10 + * draft-ietf-babel-source-specific-0 + */ + +#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 "extract.h" + +static void babel_print_v2(netdissect_options *, const u_char *cp, u_int length); + +void +babel_print(netdissect_options *ndo, + const u_char *cp, u_int length) +{ + ndo->ndo_protocol = "babel"; + ND_PRINT("babel"); + + ND_TCHECK_4(cp); + + if(GET_U_1(cp) != 42) { + ND_PRINT(" invalid header"); + return; + } else { + ND_PRINT(" %u", GET_U_1(cp + 1)); + } + + switch(GET_U_1(cp + 1)) { + case 2: + babel_print_v2(ndo, cp, length); + break; + default: + ND_PRINT(" unknown version"); + break; + } + + return; + + trunc: + nd_print_trunc(ndo); +} + +/* 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_ROUTE_REQUEST 9 +#define MESSAGE_SEQNO_REQUEST 10 +#define MESSAGE_TSPC 11 +#define MESSAGE_HMAC 12 +#define MESSAGE_UPDATE_SRC_SPECIFIC 13 /* last appearance in draft-boutier-babel-source-specific-01 */ +#define MESSAGE_REQUEST_SRC_SPECIFIC 14 /* idem */ +#define MESSAGE_MH_REQUEST_SRC_SPECIFIC 15 /* idem */ +#define MESSAGE_MAC 16 +#define MESSAGE_PC 17 +#define MESSAGE_CHALLENGE_REQUEST 18 +#define MESSAGE_CHALLENGE_REPLY 19 + +/* sub-TLVs */ +#define MESSAGE_SUB_PAD1 0 +#define MESSAGE_SUB_PADN 1 +#define MESSAGE_SUB_DIVERSITY 2 +#define MESSAGE_SUB_TIMESTAMP 3 + +/* "Mandatory" bit in sub-TLV types */ +#define MANDATORY_MASK 0x80 + +/* Flags for the Hello TLV */ +#define UNICAST_MASK 0x8000 + +/* Diversity sub-TLV channel codes */ +static const struct tok diversity_str[] = { + { 0, "reserved" }, + { 255, "all" }, + { 0, NULL } +}; + +static const char * +format_id(netdissect_options *ndo, const u_char *id) +{ + static char buf[25]; + snprintf(buf, 25, "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x", + GET_U_1(id), GET_U_1(id + 1), GET_U_1(id + 2), + GET_U_1(id + 3), GET_U_1(id + 4), GET_U_1(id + 5), + GET_U_1(id + 6), GET_U_1(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(netdissect_options *ndo, const u_char *prefix, unsigned char plen) +{ + static char buf[50]; + + /* + * prefix points to a buffer on the stack into which the prefix has + * been placed, so we can't use GET_IPADDR_STRING() or + * GET_IP6ADDR_STRING() on it. + */ + if(plen >= 96 && memcmp(prefix, v4prefix, 12) == 0) + snprintf(buf, 50, "%s/%u", ipaddr_string(ndo, prefix + 12), plen - 96); + else + snprintf(buf, 50, "%s/%u", ip6addr_string(ndo, prefix), plen); + buf[49] = '\0'; + return buf; +} + +static const char * +format_address(netdissect_options *ndo, const u_char *prefix) +{ + /* + * prefix points to a buffer on the stack into which the prefix has + * been placed, so we can't use GET_IPADDR_STRING() or + * GET_IP6ADDR_STRING() on it. + */ + if(memcmp(prefix, v4prefix, 12) == 0) + return ipaddr_string(ndo, prefix + 12); + else + return ip6addr_string(ndo, prefix); +} + +static const char * +format_interval(const uint16_t i) +{ + static char buf[sizeof("000.00s")]; + + if (i == 0) + return "0.0s (bogus)"; + snprintf(buf, sizeof(buf), "%u.%02us", i / 100, i % 100); + return buf; +} + +static const char * +format_interval_update(const uint16_t i) +{ + return i == 0xFFFF ? "infinity" : format_interval(i); +} + +static const char * +format_timestamp(const uint32_t i) +{ + static char buf[sizeof("0000.000000s")]; + snprintf(buf, sizeof(buf), "%u.%06us", i / 1000000, i % 1000000); + return buf; +} + +/* 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 interfering 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. + * o Type 3 stands for Timestamp sub-TLV, used to compute RTT between + * neighbours. In the case of a Hello TLV, the body stores a 32-bits + * timestamp, while in the case of a IHU TLV, two 32-bits timestamps are + * stored. + * + * 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. + * A type 3 sub-TLV is valid both for Hello and IHU TLVs, though the exact + * semantic of the sub-TLV is different in each case. + */ +static void +subtlvs_print(netdissect_options *ndo, + const u_char *cp, const u_char *ep, const uint8_t tlv_type) +{ + uint8_t subtype, sublen; + const char *sep; + uint32_t t1, t2; + + while (cp < ep) { + subtype = GET_U_1(cp); + cp++; + if(subtype == MESSAGE_SUB_PAD1) { + ND_PRINT(" sub-pad1"); + continue; + } + if ((MANDATORY_MASK & subtype) != 0) + ND_PRINT(" (M)"); + if(cp == ep) + goto invalid; + sublen = GET_U_1(cp); + cp++; + if(cp + sublen > ep) + goto invalid; + + switch(subtype) { + case MESSAGE_SUB_PADN: + ND_PRINT(" sub-padn"); + cp += sublen; + break; + case MESSAGE_SUB_DIVERSITY: + ND_PRINT(" sub-diversity"); + if (sublen == 0) { + ND_PRINT(" empty"); + break; + } + sep = " "; + while (sublen) { + ND_PRINT("%s%s", sep, + tok2str(diversity_str, "%u", GET_U_1(cp))); + cp++; + sep = "-"; + sublen--; + } + if(tlv_type != MESSAGE_UPDATE && + tlv_type != MESSAGE_UPDATE_SRC_SPECIFIC) + ND_PRINT(" (bogus)"); + break; + case MESSAGE_SUB_TIMESTAMP: + ND_PRINT(" sub-timestamp"); + if(tlv_type == MESSAGE_HELLO) { + if(sublen < 4) + goto invalid; + t1 = GET_BE_U_4(cp); + ND_PRINT(" %s", format_timestamp(t1)); + } else if(tlv_type == MESSAGE_IHU) { + if(sublen < 8) + goto invalid; + t1 = GET_BE_U_4(cp); + ND_PRINT(" %s", format_timestamp(t1)); + t2 = GET_BE_U_4(cp + 4); + ND_PRINT("|%s", format_timestamp(t2)); + } else + ND_PRINT(" (bogus)"); + cp += sublen; + break; + default: + ND_PRINT(" sub-unknown-0x%02x", subtype); + cp += sublen; + } /* switch */ + } /* while */ + return; + + invalid: + nd_print_invalid(ndo); +} + +#define ICHECK(i, l) \ + if ((i) + (l) > tlvs_length || (i) + (l) > packet_length_remaining) \ + goto invalid; + +static int +babel_print_v2_tlvs(netdissect_options *ndo, + const u_char *cp, u_int tlvs_length, + u_int packet_length_remaining) +{ + u_int i; + 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}; + + i = 0; + while(i < tlvs_length) { + const u_char *message; + uint8_t type; + u_int len; + + message = cp + i; + + ICHECK(i, 1); + if((type = GET_U_1(message)) == MESSAGE_PAD1) { + ND_PRINT(ndo->ndo_vflag ? "\n\tPad 1" : " pad1"); + i += 1; + continue; + } + + ICHECK(i, 2); + ND_TCHECK_2(message); + len = GET_U_1(message + 1); + + ICHECK(i, 2 + len); + ND_TCHECK_LEN(message, 2 + len); + + switch(type) { + case MESSAGE_PADN: { + if (!ndo->ndo_vflag) + ND_PRINT(" padN"); + else + ND_PRINT("\n\tPad %u", len + 2); + } + break; + + case MESSAGE_ACK_REQ: { + u_short nonce, interval; + if (!ndo->ndo_vflag) + ND_PRINT(" ack-req"); + else { + ND_PRINT("\n\tAcknowledgment Request "); + if(len < 6) goto invalid; + nonce = GET_BE_U_2(message + 4); + interval = GET_BE_U_2(message + 6); + ND_PRINT("%04x %s", nonce, format_interval(interval)); + } + } + break; + + case MESSAGE_ACK: { + u_short nonce; + if (!ndo->ndo_vflag) + ND_PRINT(" ack"); + else { + ND_PRINT("\n\tAcknowledgment "); + if(len < 2) goto invalid; + nonce = GET_BE_U_2(message + 2); + ND_PRINT("%04x", nonce); + } + } + break; + + case MESSAGE_HELLO: { + u_short seqno, interval, unicast; + if (!ndo->ndo_vflag) + ND_PRINT(" hello"); + else { + ND_PRINT("\n\tHello "); + if(len < 6) goto invalid; + unicast = (GET_BE_U_2(message + 2) & UNICAST_MASK); + seqno = GET_BE_U_2(message + 4); + interval = GET_BE_U_2(message + 6); + if(unicast) + ND_PRINT("(Unicast) "); + ND_PRINT("seqno %u ", seqno); + if(interval!=0) + ND_PRINT("interval %s", format_interval(interval)); + else + ND_PRINT("unscheduled"); + /* Extra data. */ + if(len > 6) + subtlvs_print(ndo, message + 8, message + 2 + len, type); + } + } + break; + + case MESSAGE_IHU: { + unsigned short rxcost, interval; + if (!ndo->ndo_vflag) + ND_PRINT(" ihu"); + else { + u_char address[16]; + u_char ae; + int rc; + ND_PRINT("\n\tIHU "); + if(len < 6) goto invalid; + rxcost = GET_BE_U_2(message + 4); + interval = GET_BE_U_2(message + 6); + ae = GET_U_1(message + 2); + rc = network_address(ae, message + 8, + len - 6, address); + if(rc < 0) { nd_print_trunc(ndo); break; } + ND_PRINT("%s rxcost %u interval %s", + ae == 0 ? "any" : format_address(ndo, address), + rxcost, format_interval(interval)); + /* Extra data. */ + if((u_int)rc < len - 6) + subtlvs_print(ndo, message + 8 + rc, message + 2 + len, + type); + } + } + break; + + case MESSAGE_ROUTER_ID: { + if (!ndo->ndo_vflag) + ND_PRINT(" router-id"); + else { + ND_PRINT("\n\tRouter Id"); + if(len < 10) goto invalid; + ND_PRINT(" %s", format_id(ndo, message + 4)); + } + } + break; + + case MESSAGE_NH: { + if (!ndo->ndo_vflag) + ND_PRINT(" nh"); + else { + int rc; + u_char ae; + u_char nh[16]; + ND_PRINT("\n\tNext Hop"); + if(len < 2) goto invalid; + ae = GET_U_1(message + 2); + rc = network_address(ae, message + 4, + len - 2, nh); + if(rc < 0) goto invalid; + ND_PRINT(" %s", ae == 0 ? "invalid AE 0" : format_address(ndo, nh)); + } + } + break; + + case MESSAGE_UPDATE: { + if (!ndo->ndo_vflag) { + ND_PRINT(" update"); + if(len < 10) + goto invalid; + else + ND_PRINT("%s%s%s", + (GET_U_1(message + 3) & 0x80) ? "/prefix": "", + (GET_U_1(message + 3) & 0x40) ? "/id" : "", + (GET_U_1(message + 3) & 0x3f) ? "/unknown" : ""); + } else { + u_short interval, seqno, metric; + u_char ae, plen; + int rc; + u_char prefix[16]; + ND_PRINT("\n\tUpdate"); + if(len < 10) goto invalid; + ae = GET_U_1(message + 2); + plen = GET_U_1(message + 4) + (GET_U_1(message + 2) == 1 ? 96 : 0); + rc = network_prefix(ae, + GET_U_1(message + 4), + GET_U_1(message + 5), + message + 12, + GET_U_1(message + 2) == 1 ? v4_prefix : v6_prefix, + len - 10, prefix); + if(rc < 0) goto invalid; + interval = GET_BE_U_2(message + 6); + seqno = GET_BE_U_2(message + 8); + metric = GET_BE_U_2(message + 10); + ND_PRINT("%s%s%s %s metric %u seqno %u interval %s", + (GET_U_1(message + 3) & 0x80) ? "/prefix": "", + (GET_U_1(message + 3) & 0x40) ? "/id" : "", + (GET_U_1(message + 3) & 0x3f) ? "/unknown" : "", + ae == 0 ? "any" : format_prefix(ndo, prefix, plen), + metric, seqno, format_interval_update(interval)); + if(GET_U_1(message + 3) & 0x80) { + if(GET_U_1(message + 2) == 1) + memcpy(v4_prefix, prefix, 16); + else + memcpy(v6_prefix, prefix, 16); + } + /* extra data? */ + if((u_int)rc < len - 10) + subtlvs_print(ndo, message + 12 + rc, message + 2 + len, type); + } + } + break; + + case MESSAGE_ROUTE_REQUEST: { + if (!ndo->ndo_vflag) + ND_PRINT(" route-request"); + else { + int rc; + u_char prefix[16], ae, plen; + ND_PRINT("\n\tRoute Request "); + if(len < 2) goto invalid; + ae = GET_U_1(message + 2); + plen = GET_U_1(message + 3) + (GET_U_1(message + 2) == 1 ? 96 : 0); + rc = network_prefix(ae, + GET_U_1(message + 3), 0, + message + 4, NULL, len - 2, prefix); + if(rc < 0) goto invalid; + ND_PRINT("for %s", + ae == 0 ? "any" : format_prefix(ndo, prefix, plen)); + } + } + break; + + case MESSAGE_SEQNO_REQUEST : { + if (!ndo->ndo_vflag) + ND_PRINT(" seqno-request"); + else { + int rc; + u_short seqno; + u_char prefix[16], ae, plen; + ND_PRINT("\n\tSeqno Request "); + if(len < 14) goto invalid; + ae = GET_U_1(message + 2); + seqno = GET_BE_U_2(message + 4); + rc = network_prefix(ae, + GET_U_1(message + 3), 0, + message + 16, NULL, len - 14, prefix); + if(rc < 0) goto invalid; + plen = GET_U_1(message + 3) + (GET_U_1(message + 2) == 1 ? 96 : 0); + ND_PRINT("(%u hops) for %s seqno %u id %s", + GET_U_1(message + 6), + ae == 0 ? "invalid AE 0" : format_prefix(ndo, prefix, plen), + seqno, format_id(ndo, message + 8)); + } + } + break; + case MESSAGE_TSPC : + if (!ndo->ndo_vflag) + ND_PRINT(" tspc"); + else { + ND_PRINT("\n\tTS/PC "); + if(len < 6) goto invalid; + ND_PRINT("timestamp %u packetcounter %u", + GET_BE_U_4(message + 4), + GET_BE_U_2(message + 2)); + } + break; + case MESSAGE_HMAC : { + if (!ndo->ndo_vflag) + ND_PRINT(" hmac"); + else { + unsigned j; + ND_PRINT("\n\tHMAC "); + if(len < 18) goto invalid; + ND_PRINT("key-id %u digest-%u ", GET_BE_U_2(message + 2), + len - 2); + for (j = 0; j < len - 2; j++) + ND_PRINT("%02X", GET_U_1(message + j + 4)); + } + } + break; + + case MESSAGE_UPDATE_SRC_SPECIFIC : { + if(!ndo->ndo_vflag) { + ND_PRINT(" ss-update"); + } else { + u_char prefix[16], src_prefix[16]; + u_short interval, seqno, metric; + u_char ae, plen, src_plen, omitted; + int rc; + int parsed_len = 10; + ND_PRINT("\n\tSS-Update"); + if(len < 10) goto invalid; + ae = GET_U_1(message + 2); + src_plen = GET_U_1(message + 3); + plen = GET_U_1(message + 4); + omitted = GET_U_1(message + 5); + interval = GET_BE_U_2(message + 6); + seqno = GET_BE_U_2(message + 8); + metric = GET_BE_U_2(message + 10); + rc = network_prefix(ae, plen, omitted, message + 2 + parsed_len, + ae == 1 ? v4_prefix : v6_prefix, + len - parsed_len, prefix); + if(rc < 0) goto invalid; + if(ae == 1) + plen += 96; + parsed_len += rc; + rc = network_prefix(ae, src_plen, 0, message + 2 + parsed_len, + NULL, len - parsed_len, src_prefix); + if(rc < 0) goto invalid; + if(ae == 1) + src_plen += 96; + parsed_len += rc; + + ND_PRINT(" %s from", format_prefix(ndo, prefix, plen)); + ND_PRINT(" %s metric %u seqno %u interval %s", + format_prefix(ndo, src_prefix, src_plen), + metric, seqno, format_interval_update(interval)); + /* extra data? */ + if((u_int)parsed_len < len) + subtlvs_print(ndo, message + 2 + parsed_len, + message + 2 + len, type); + } + } + break; + + case MESSAGE_REQUEST_SRC_SPECIFIC : { + if(!ndo->ndo_vflag) + ND_PRINT(" ss-request"); + else { + int rc, parsed_len = 3; + u_char ae, plen, src_plen, prefix[16], src_prefix[16]; + ND_PRINT("\n\tSS-Request "); + if(len < 3) goto invalid; + ae = GET_U_1(message + 2); + plen = GET_U_1(message + 3); + src_plen = GET_U_1(message + 4); + rc = network_prefix(ae, plen, 0, message + 2 + parsed_len, + NULL, len - parsed_len, prefix); + if(rc < 0) goto invalid; + if(ae == 1) + plen += 96; + parsed_len += rc; + rc = network_prefix(ae, src_plen, 0, message + 2 + parsed_len, + NULL, len - parsed_len, src_prefix); + if(rc < 0) goto invalid; + if(ae == 1) + src_plen += 96; + parsed_len += rc; + if(ae == 0) { + ND_PRINT("for any"); + } else { + ND_PRINT("for (%s, ", format_prefix(ndo, prefix, plen)); + ND_PRINT("%s)", format_prefix(ndo, src_prefix, src_plen)); + } + } + } + break; + + case MESSAGE_MH_REQUEST_SRC_SPECIFIC : { + if(!ndo->ndo_vflag) + ND_PRINT(" ss-mh-request"); + else { + int rc, parsed_len = 14; + u_short seqno; + u_char ae, plen, src_plen, prefix[16], src_prefix[16], hopc; + const u_char *router_id = NULL; + ND_PRINT("\n\tSS-MH-Request "); + if(len < 14) goto invalid; + ae = GET_U_1(message + 2); + plen = GET_U_1(message + 3); + seqno = GET_BE_U_2(message + 4); + hopc = GET_U_1(message + 6); + src_plen = GET_U_1(message + 7); + router_id = message + 8; + rc = network_prefix(ae, plen, 0, message + 2 + parsed_len, + NULL, len - parsed_len, prefix); + if(rc < 0) goto invalid; + if(ae == 1) + plen += 96; + parsed_len += rc; + rc = network_prefix(ae, src_plen, 0, message + 2 + parsed_len, + NULL, len - parsed_len, src_prefix); + if(rc < 0) goto invalid; + if(ae == 1) + src_plen += 96; + ND_PRINT("(%u hops) for (%s, ", + hopc, format_prefix(ndo, prefix, plen)); + ND_PRINT("%s) seqno %u id %s", + format_prefix(ndo, src_prefix, src_plen), + seqno, format_id(ndo, router_id)); + } + } + break; + + case MESSAGE_MAC: { + if (!ndo->ndo_vflag) + ND_PRINT(" mac"); + else { + ND_PRINT("\n\tMAC "); + ND_PRINT("len %u", len); + } + } + break; + + case MESSAGE_PC: { + if (!ndo->ndo_vflag) + ND_PRINT(" pc"); + else { + ND_PRINT("\n\tPC"); + if(len < 4) goto invalid; + ND_PRINT(" value %u", + GET_BE_U_4(message + 2)); + ND_PRINT(" index len %u", len-4); + } + } + break; + + case MESSAGE_CHALLENGE_REQUEST: { + if (!ndo->ndo_vflag) + ND_PRINT(" challenge_request"); + else { + ND_PRINT("\n\tChallenge Request"); + if(len > 192) goto invalid; + ND_PRINT(" len %u", len); + } + } + break; + + case MESSAGE_CHALLENGE_REPLY: { + if (!ndo->ndo_vflag) + ND_PRINT(" challenge_reply"); + else { + ND_PRINT("\n\tChallenge Reply"); + if (len > 192) goto invalid; + ND_PRINT(" len %u", len); + } + } + break; + + default: + if (!ndo->ndo_vflag) + ND_PRINT(" unknown"); + else + ND_PRINT("\n\tUnknown message type %u", type); + } + i += len + 2; + } + + return 0; /* OK */ + +trunc: + return -1; /* packet truncated by capture process */ + +invalid: + return -2; /* packet is invalid */ +} + +static void +babel_print_v2(netdissect_options *ndo, + const u_char *cp, u_int length) +{ + u_short bodylen; + int ret; + + ND_TCHECK_4(cp); + if (length < 4) + goto invalid; + bodylen = GET_BE_U_2(cp + 2); + ND_PRINT(" (%u)", bodylen); + length -= 4; + cp += 4; + + /* Process the TLVs in the body */ + if (length < bodylen) + goto invalid; + ret = babel_print_v2_tlvs(ndo, cp, bodylen, length); + if (ret == -1) + goto trunc; + if (ret == -2) + goto invalid; + length -= bodylen; + cp += bodylen; + + /* If there's a trailer, process the TLVs in the trailer */ + if (length != 0) { + if(ndo->ndo_vflag) ND_PRINT("\n\t----"); + else ND_PRINT(" |"); + ret = babel_print_v2_tlvs(ndo, cp, length, length); + if (ret == -1) + goto trunc; + if (ret == -2) + goto invalid; + } + return; + + trunc: + nd_print_trunc(ndo); + return; + + invalid: + nd_print_invalid(ndo); +} |