u_int
chdlc_print(netdissect_options *ndo, register const u_char *p, u_int length)
{
u_int proto;
const u_char *bp = p;
if (length < CHDLC_HDRLEN)
goto trunc;
ND_TCHECK2(*p, CHDLC_HDRLEN);
proto = EXTRACT_16BITS(&p[2]);
if (ndo->ndo_eflag) {
ND_PRINT((ndo, "%s, ethertype %s (0x%04x), length %u: ",
tok2str(chdlc_cast_values, "0x%02x", p[0]),
tok2str(ethertype_values, "Unknown", proto),
proto,
length));
}
length -= CHDLC_HDRLEN;
p += CHDLC_HDRLEN;
switch (proto) {
case ETHERTYPE_IP:
ip_print(ndo, p, length);
break;
case ETHERTYPE_IPV6:
ip6_print(ndo, p, length);
break;
case CHDLC_TYPE_SLARP:
chdlc_slarp_print(ndo, p, length);
break;
#if 0
case CHDLC_TYPE_CDP:
chdlc_cdp_print(p, length);
break;
#endif
case ETHERTYPE_MPLS:
case ETHERTYPE_MPLS_MULTI:
mpls_print(ndo, p, length);
break;
case ETHERTYPE_ISO:
/* is the fudge byte set ? lets verify by spotting ISO headers */
if (length < 2)
goto trunc;
ND_TCHECK_16BITS(p);
if (*(p+1) == 0x81 ||
*(p+1) == 0x82 ||
*(p+1) == 0x83)
isoclns_print(ndo, p + 1, length - 1);
else
isoclns_print(ndo, p, length);
break;
default:
if (!ndo->ndo_eflag)
ND_PRINT((ndo, "unknown CHDLC protocol (0x%04x)", proto));
break;
}
return (CHDLC_HDRLEN);
trunc:
ND_PRINT((ndo, "[|chdlc]"));
return ndo->ndo_snapend - bp;
}
void
icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *bp2,
int fragmented)
{
char *cp;
const struct icmp *dp;
const struct icmp_ext_t *ext_dp;
const struct ip *ip;
const char *str, *fmt;
const struct ip *oip;
const struct udphdr *ouh;
const uint8_t *obj_tptr;
uint32_t raw_label;
const u_char *snapend_save;
const struct icmp_mpls_ext_object_header_t *icmp_mpls_ext_object_header;
u_int hlen, dport, mtu, obj_tlen, obj_class_num, obj_ctype;
char buf[MAXHOSTNAMELEN + 100];
struct cksum_vec vec[1];
dp = (const struct icmp *)bp;
ext_dp = (const struct icmp_ext_t *)bp;
ip = (const struct ip *)bp2;
str = buf;
ND_TCHECK(dp->icmp_code);
switch (dp->icmp_type) {
case ICMP_ECHO:
case ICMP_ECHOREPLY:
ND_TCHECK(dp->icmp_seq);
(void)snprintf(buf, sizeof(buf), "echo %s, id %u, seq %u",
dp->icmp_type == ICMP_ECHO ?
"request" : "reply",
EXTRACT_16BITS(&dp->icmp_id),
EXTRACT_16BITS(&dp->icmp_seq));
break;
case ICMP_UNREACH:
ND_TCHECK(dp->icmp_ip.ip_dst);
switch (dp->icmp_code) {
case ICMP_UNREACH_PROTOCOL:
ND_TCHECK(dp->icmp_ip.ip_p);
(void)snprintf(buf, sizeof(buf),
"%s protocol %d unreachable",
ipaddr_string(ndo, &dp->icmp_ip.ip_dst),
dp->icmp_ip.ip_p);
break;
case ICMP_UNREACH_PORT:
ND_TCHECK(dp->icmp_ip.ip_p);
oip = &dp->icmp_ip;
hlen = IP_HL(oip) * 4;
ouh = (const struct udphdr *)(((const u_char *)oip) + hlen);
ND_TCHECK(ouh->uh_dport);
dport = EXTRACT_16BITS(&ouh->uh_dport);
switch (oip->ip_p) {
case IPPROTO_TCP:
(void)snprintf(buf, sizeof(buf),
"%s tcp port %s unreachable",
ipaddr_string(ndo, &oip->ip_dst),
tcpport_string(ndo, dport));
break;
case IPPROTO_UDP:
(void)snprintf(buf, sizeof(buf),
"%s udp port %s unreachable",
ipaddr_string(ndo, &oip->ip_dst),
udpport_string(ndo, dport));
break;
default:
(void)snprintf(buf, sizeof(buf),
"%s protocol %d port %d unreachable",
ipaddr_string(ndo, &oip->ip_dst),
oip->ip_p, dport);
break;
}
break;
case ICMP_UNREACH_NEEDFRAG:
{
register const struct mtu_discovery *mp;
mp = (const struct mtu_discovery *)(const u_char *)&dp->icmp_void;
mtu = EXTRACT_16BITS(&mp->nexthopmtu);
if (mtu) {
(void)snprintf(buf, sizeof(buf),
"%s unreachable - need to frag (mtu %d)",
ipaddr_string(ndo, &dp->icmp_ip.ip_dst), mtu);
} else {
(void)snprintf(buf, sizeof(buf),
"%s unreachable - need to frag",
ipaddr_string(ndo, &dp->icmp_ip.ip_dst));
}
}
break;
default:
fmt = tok2str(unreach2str, "#%d %%s unreachable",
dp->icmp_code);
(void)snprintf(buf, sizeof(buf), fmt,
ipaddr_string(ndo, &dp->icmp_ip.ip_dst));
break;
}
break;
case ICMP_REDIRECT:
ND_TCHECK(dp->icmp_ip.ip_dst);
fmt = tok2str(type2str, "redirect-#%d %%s to net %%s",
dp->icmp_code);
(void)snprintf(buf, sizeof(buf), fmt,
ipaddr_string(ndo, &dp->icmp_ip.ip_dst),
ipaddr_string(ndo, &dp->icmp_gwaddr));
break;
case ICMP_ROUTERADVERT:
{
register const struct ih_rdiscovery *ihp;
register const struct id_rdiscovery *idp;
u_int lifetime, num, size;
(void)snprintf(buf, sizeof(buf), "router advertisement");
cp = buf + strlen(buf);
ihp = (const struct ih_rdiscovery *)&dp->icmp_void;
ND_TCHECK(*ihp);
(void)strncpy(cp, " lifetime ", sizeof(buf) - (cp - buf));
cp = buf + strlen(buf);
lifetime = EXTRACT_16BITS(&ihp->ird_lifetime);
if (lifetime < 60) {
(void)snprintf(cp, sizeof(buf) - (cp - buf), "%u",
lifetime);
} else if (lifetime < 60 * 60) {
(void)snprintf(cp, sizeof(buf) - (cp - buf), "%u:%02u",
lifetime / 60, lifetime % 60);
} else {
(void)snprintf(cp, sizeof(buf) - (cp - buf),
"%u:%02u:%02u",
lifetime / 3600,
(lifetime % 3600) / 60,
lifetime % 60);
}
cp = buf + strlen(buf);
num = ihp->ird_addrnum;
(void)snprintf(cp, sizeof(buf) - (cp - buf), " %d:", num);
cp = buf + strlen(buf);
size = ihp->ird_addrsiz;
if (size != 2) {
(void)snprintf(cp, sizeof(buf) - (cp - buf),
" [size %d]", size);
break;
}
idp = (const struct id_rdiscovery *)&dp->icmp_data;
while (num-- > 0) {
ND_TCHECK(*idp);
(void)snprintf(cp, sizeof(buf) - (cp - buf), " {%s %u}",
ipaddr_string(ndo, &idp->ird_addr),
EXTRACT_32BITS(&idp->ird_pref));
cp = buf + strlen(buf);
++idp;
}
}
break;
case ICMP_TIMXCEED:
ND_TCHECK(dp->icmp_ip.ip_dst);
switch (dp->icmp_code) {
case ICMP_TIMXCEED_INTRANS:
str = "time exceeded in-transit";
break;
case ICMP_TIMXCEED_REASS:
str = "ip reassembly time exceeded";
break;
default:
(void)snprintf(buf, sizeof(buf), "time exceeded-#%d",
dp->icmp_code);
break;
}
break;
case ICMP_PARAMPROB:
if (dp->icmp_code)
(void)snprintf(buf, sizeof(buf),
"parameter problem - code %d", dp->icmp_code);
else {
ND_TCHECK(dp->icmp_pptr);
(void)snprintf(buf, sizeof(buf),
"parameter problem - octet %d", dp->icmp_pptr);
}
break;
case ICMP_MASKREPLY:
ND_TCHECK(dp->icmp_mask);
(void)snprintf(buf, sizeof(buf), "address mask is 0x%08x",
EXTRACT_32BITS(&dp->icmp_mask));
break;
case ICMP_TSTAMP:
ND_TCHECK(dp->icmp_seq);
(void)snprintf(buf, sizeof(buf),
"time stamp query id %u seq %u",
EXTRACT_16BITS(&dp->icmp_id),
EXTRACT_16BITS(&dp->icmp_seq));
break;
case ICMP_TSTAMPREPLY:
ND_TCHECK(dp->icmp_ttime);
(void)snprintf(buf, sizeof(buf),
"time stamp reply id %u seq %u: org %s",
EXTRACT_16BITS(&dp->icmp_id),
EXTRACT_16BITS(&dp->icmp_seq),
icmp_tstamp_print(EXTRACT_32BITS(&dp->icmp_otime)));
(void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", recv %s",
icmp_tstamp_print(EXTRACT_32BITS(&dp->icmp_rtime)));
(void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", xmit %s",
icmp_tstamp_print(EXTRACT_32BITS(&dp->icmp_ttime)));
break;
default:
str = tok2str(icmp2str, "type-#%d", dp->icmp_type);
break;
}
ND_PRINT((ndo, "ICMP %s, length %u", str, plen));
if (ndo->ndo_vflag && !fragmented) { /* don't attempt checksumming if this is a frag */
uint16_t sum, icmp_sum;
if (ND_TTEST2(*bp, plen)) {
vec[0].ptr = (const uint8_t *)(const void *)dp;
vec[0].len = plen;
sum = in_cksum(vec, 1);
if (sum != 0) {
icmp_sum = EXTRACT_16BITS(&dp->icmp_cksum);
ND_PRINT((ndo, " (wrong icmp cksum %x (->%x)!)",
icmp_sum,
in_cksum_shouldbe(icmp_sum, sum)));
}
}
}
/*
* print the remnants of the IP packet.
* save the snaplength as this may get overidden in the IP printer.
*/
if (ndo->ndo_vflag >= 1 && ICMP_ERRTYPE(dp->icmp_type)) {
bp += 8;
ND_PRINT((ndo, "\n\t"));
ip = (const struct ip *)bp;
ndo->ndo_snaplen = ndo->ndo_snapend - bp;
snapend_save = ndo->ndo_snapend;
ND_TCHECK_16BITS(&ip->ip_len);
ip_print(ndo, bp, EXTRACT_16BITS(&ip->ip_len));
ndo->ndo_snapend = snapend_save;
}
/*
* Attempt to decode the MPLS extensions only for some ICMP types.
*/
if (ndo->ndo_vflag >= 1 && plen > ICMP_EXTD_MINLEN && ICMP_MPLS_EXT_TYPE(dp->icmp_type)) {
ND_TCHECK(*ext_dp);
/*
* Check first if the mpls extension header shows a non-zero length.
* If the length field is not set then silently verify the checksum
* to check if an extension header is present. This is expedient,
* however not all implementations set the length field proper.
*/
if (!ext_dp->icmp_length &&
ND_TTEST2(ext_dp->icmp_ext_version_res, plen - ICMP_EXTD_MINLEN)) {
vec[0].ptr = (const uint8_t *)(const void *)&ext_dp->icmp_ext_version_res;
vec[0].len = plen - ICMP_EXTD_MINLEN;
if (in_cksum(vec, 1)) {
return;
}
}
ND_PRINT((ndo, "\n\tMPLS extension v%u",
ICMP_MPLS_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res))));
/*
* Sanity checking of the header.
*/
if (ICMP_MPLS_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)) !=
ICMP_MPLS_EXT_VERSION) {
ND_PRINT((ndo, " packet not supported"));
return;
}
hlen = plen - ICMP_EXTD_MINLEN;
if (ND_TTEST2(ext_dp->icmp_ext_version_res, hlen)) {
vec[0].ptr = (const uint8_t *)(const void *)&ext_dp->icmp_ext_version_res;
vec[0].len = hlen;
ND_PRINT((ndo, ", checksum 0x%04x (%scorrect), length %u",
EXTRACT_16BITS(ext_dp->icmp_ext_checksum),
in_cksum(vec, 1) ? "in" : "",
hlen));
}
hlen -= 4; /* subtract common header size */
obj_tptr = (const uint8_t *)ext_dp->icmp_ext_data;
while (hlen > sizeof(struct icmp_mpls_ext_object_header_t)) {
icmp_mpls_ext_object_header = (const struct icmp_mpls_ext_object_header_t *)obj_tptr;
ND_TCHECK(*icmp_mpls_ext_object_header);
obj_tlen = EXTRACT_16BITS(icmp_mpls_ext_object_header->length);
obj_class_num = icmp_mpls_ext_object_header->class_num;
obj_ctype = icmp_mpls_ext_object_header->ctype;
obj_tptr += sizeof(struct icmp_mpls_ext_object_header_t);
ND_PRINT((ndo, "\n\t %s Object (%u), Class-Type: %u, length %u",
tok2str(icmp_mpls_ext_obj_values,"unknown",obj_class_num),
obj_class_num,
obj_ctype,
obj_tlen));
hlen-=sizeof(struct icmp_mpls_ext_object_header_t); /* length field includes tlv header */
/* infinite loop protection */
if ((obj_class_num == 0) ||
(obj_tlen < sizeof(struct icmp_mpls_ext_object_header_t))) {
return;
}
obj_tlen-=sizeof(struct icmp_mpls_ext_object_header_t);
switch (obj_class_num) {
case 1:
switch(obj_ctype) {
case 1:
ND_TCHECK2(*obj_tptr, 4);
raw_label = EXTRACT_32BITS(obj_tptr);
ND_PRINT((ndo, "\n\t label %u, exp %u", MPLS_LABEL(raw_label), MPLS_EXP(raw_label)));
if (MPLS_STACK(raw_label))
ND_PRINT((ndo, ", [S]"));
ND_PRINT((ndo, ", ttl %u", MPLS_TTL(raw_label)));
break;
default:
print_unknown_data(ndo, obj_tptr, "\n\t ", obj_tlen);
}
break;
/*
* FIXME those are the defined objects that lack a decoder
* you are welcome to contribute code ;-)
*/
case 2:
default:
print_unknown_data(ndo, obj_tptr, "\n\t ", obj_tlen);
break;
}
if (hlen < obj_tlen)
break;
hlen -= obj_tlen;
obj_tptr += obj_tlen;
}
}
return;
trunc:
ND_PRINT((ndo, "[|icmp]"));
}
