hi all,
there wasa bug in the way i calculated the checksum over LSPs;
additionally the TLV parser recognizes [decoder is still left]
no the IS Alias TLV #24
/hannes
Index: print-isoclns.c
===================================================================
RCS file: /tcpdump/master/tcpdump/print-isoclns.c,v
retrieving revision 1.43
diff -u -r1.43 print-isoclns.c
--- print-isoclns.c 2002/04/09 08:27:25 1.43
+++ print-isoclns.c 2002/04/11 19:49:43
@@ -107,6 +107,7 @@
#define TLV_CHECKSUM 12
#define TLV_LSP_BUFFERSIZE 14
#define TLV_EXT_IS_REACH 22
+#define TLV_IS_ALIAS_ID 24
#define TLV_DECNET_PHASE4 42
#define TLV_LUCENT_PRIVATE 66
#define TLV_IP_REACH 128
@@ -143,6 +144,7 @@
{ TLV_CHECKSUM, "Checksum"},
{ TLV_LSP_BUFFERSIZE, "LSP Buffersize"},
{ TLV_EXT_IS_REACH, "Extended IS Reachability"},
+ { TLV_IS_ALIAS_ID, "IS Alias ID"},
{ TLV_DECNET_PHASE4, "DECnet Phase IV"},
{ TLV_LUCENT_PRIVATE, "Lucent Proprietary"},
{ TLV_IP_REACH, "IP Internal reachability"},
@@ -325,7 +327,7 @@
u_char neighbor_ext_local_circuit_id[4];
};
-static int osi_cksum(const u_char *, u_int, u_char *);
+static int osi_cksum(const u_char *, u_int);
static void esis_print(const u_char *, u_int);
static int isis_print(const u_char *, u_int);
@@ -500,7 +502,6 @@
const u_char *ep;
u_int li;
const struct esis_hdr *eh;
- u_char off[2];
if (length <= 2) {
if (qflag)
@@ -547,10 +548,8 @@
printf(" type %d", eh->type & 0x1f);
break;
}
- off[0] = eh->cksum[0];
- off[1] = eh->cksum[1];
- if (vflag && osi_cksum(p, li, off)) {
- printf(" bad cksum (got %02x%02x)",
+ if (vflag && osi_cksum(p, li)) {
+ printf(" bad cksum (got 0x%02x%02x)",
eh->cksum[1], eh->cksum[0]);
default_print(p, length);
return;
@@ -668,49 +667,71 @@
return (1);
}
-static int
+char *isis_print_sysid (const u_char *);
+/* allocate space for the following string
+ * xxxx.xxxx.xxxx
+ * 14 bytes plus one termination byte */
+char sysid[15];
+char *
isis_print_sysid(const u_char *cp)
{
int i;
+ char *pos = sysid;
for (i = 1; i <= 6; i++) {
if (!TTEST2(*cp, 1))
return (0);
- printf("%02x", *cp++);
+ pos+=sprintf(pos, "%02x", *cp++);
if ((i==2)^(i==4)) {
- printf(".");
+ pos+=sprintf(pos, ".");
}
}
- return (1);
+ *(pos) = '\0';
+ return (sysid);
}
-static int
+
+char *isis_print_nodeid (const u_char *);
+/* allocate space for the following string
+ * xxxx.xxxx.xxxx.yy
+ * 17 bytes plus one termination byte */
+char nodeid[18];
+char *
isis_print_nodeid(const u_char *cp)
{
int i;
+ char *pos = nodeid;
for (i = 1; i <= 7; i++) {
if (!TTEST2(*cp, 1))
return (0);
- printf("%02x", *cp++);
+ pos+=sprintf(pos, "%02x", *cp++);
if ((i & 1) == 0) {
- printf(".");
+ pos+=sprintf(pos, ".");
}
}
- return (1);
+ *(pos) = '\0';
+ return (nodeid);
}
-static void
+char *isis_print_lspid (const u_char *);
+/* allocate space for the following string
+ * xxxx.xxxx.xxxx.yy-zz
+ * 20 bytes plus one termination byte */
+char lspid[21];
+char *
isis_print_lspid(const u_char *cp)
{
int i;
+ char *pos = lspid;
for (i = 1; i <= 7; i++) {
- printf("%02x", *cp++);
+ pos+=sprintf(pos, "%02x", *cp++);
if ((i & 1) == 0)
- printf(".");
+ pos+=sprintf(pos, ".");
}
- printf("-%02x", *cp);
+ pos+=sprintf(pos, "-%02x", *cp);
+ return (lspid);
}
/*
@@ -1060,10 +1081,9 @@
#ifdef INET6
u_char prefix6[16]; /* copy buffer for ipv6 prefixes */
#endif
- u_char off[2];
-
packet_len=length;
- optr = p; /* initialize the _o_riginal pointer - need it for parsing the checksum
TLV */
+ optr = p; /* initialize the _o_riginal pointer to the packet start -
+ need it for parsing the checksum TLV */
header = (const struct isis_common_header *)p;
TCHECK(*header);
pptr = p+(ISIS_COMMON_HEADER_SIZE);
@@ -1165,17 +1185,17 @@
}
TCHECK(*header_iih_lan);
- printf("\n\t\t source-id: ");
- isis_print_sysid(header_iih_lan->source_id);
- printf(", holding time: %u, %s",
+ printf("\n\t\t source-id: %s, holding time: %u, %s",
+ isis_print_sysid(header_iih_lan->source_id),
EXTRACT_16BITS(header_iih_lan->holding_time),
tok2str(isis_iih_circuit_type_values,
"unknown circuit type 0x%02x",
header_iih_lan->circuit_type));
- printf("\n\t\t lan-id: ");
- isis_print_nodeid(header_iih_lan->lan_id);
- printf(", Priority: %u",(header_iih_lan->priority) & PRIORITY_MASK);
+ printf("\n\t\t lan-id: %s, Priority: %u, PDU Length: %u",
+ isis_print_nodeid(header_iih_lan->lan_id),
+ (header_iih_lan->priority) & PRIORITY_MASK,
+ pdu_len);
packet_len -= (ISIS_COMMON_HEADER_SIZE+ISIS_IIH_LAN_HEADER_SIZE);
pptr = p + (ISIS_COMMON_HEADER_SIZE+ISIS_IIH_LAN_HEADER_SIZE);
@@ -1195,14 +1215,14 @@
}
TCHECK(*header_iih_ptp);
- printf("\n\t\t source-id: ");
- isis_print_sysid(header_iih_ptp->source_id);
- printf(", holding time: %us",EXTRACT_16BITS(header_iih_ptp->holding_time));
- printf(", circuit-id: 0x%02x, %s",
+ printf("\n\t\t source-id: %s, holding time: %us, circuit-id: 0x%02x, %s, PDU
+Length: %u",
+ isis_print_sysid(header_iih_ptp->source_id),
+ EXTRACT_16BITS(header_iih_ptp->holding_time),
header_iih_ptp->circuit_id,
tok2str(isis_iih_circuit_type_values,
"unknown circuit type 0x%02x",
- header_iih_ptp->circuit_type));
+ header_iih_ptp->circuit_type),
+ pdu_len);
packet_len -= (ISIS_COMMON_HEADER_SIZE+ISIS_IIH_PTP_HEADER_SIZE);
pptr = p + (ISIS_COMMON_HEADER_SIZE+ISIS_IIH_PTP_HEADER_SIZE);
@@ -1223,13 +1243,17 @@
}
TCHECK(*header_lsp);
- printf("\n\t\t lsp-id: ");
- isis_print_lspid(header_lsp->lsp_id);
- printf(", seq: 0x%08x",EXTRACT_32BITS(header_lsp->sequence_number));
- printf(", lifetime: %5us",EXTRACT_16BITS(header_lsp->remaining_lifetime));
- printf("\n\t\t chksum: 0x%04x",EXTRACT_16BITS(header_lsp->checksum));
- /* verify the checksum */
- if (osi_cksum(optr, length, off))
+ printf("\n\t\t lsp-id: %s, seq: 0x%08x, lifetime: %5us",
+ isis_print_lspid(header_lsp->lsp_id),
+ EXTRACT_32BITS(header_lsp->sequence_number),
+ EXTRACT_16BITS(header_lsp->remaining_lifetime));
+ printf("\n\t\t chksum: 0x%04x, PDU Length: %u",
+ EXTRACT_16BITS(header_lsp->checksum),
+ pdu_len);
+ /* verify the checksum -
+ * checking starts at the lsp-id field
+ * which is 12 bytes after the packet start*/
+ if (osi_cksum(optr+12, length-12))
printf(" (incorrect)");
else
printf(" (correct)");
@@ -1265,12 +1289,13 @@
}
TCHECK(*header_csnp);
- printf("\n\t\t source-id: ");
- isis_print_nodeid(header_csnp->source_id);
- printf("\n\t\t start lsp-id: ");
- isis_print_lspid(header_csnp->start_lsp_id);
- printf("\n\t\t end lsp-id: ");
- isis_print_lspid(header_csnp->end_lsp_id);
+ printf("\n\t\t source-id: %s, PDU Length: %u",
+ isis_print_nodeid(header_csnp->source_id),
+ pdu_len);
+ printf("\n\t\t start lsp-id: %s",
+ isis_print_lspid(header_csnp->start_lsp_id));
+ printf("\n\t\t end lsp-id: %s",
+ isis_print_lspid(header_csnp->end_lsp_id));
packet_len -= (ISIS_COMMON_HEADER_SIZE+ISIS_CSNP_HEADER_SIZE);
pptr = p + (ISIS_COMMON_HEADER_SIZE+ISIS_CSNP_HEADER_SIZE);
@@ -1291,8 +1316,8 @@
}
TCHECK(*header_psnp);
- printf("\n\t\t source-id: ");
- isis_print_nodeid(header_psnp->source_id);
+ printf("\n\t\t source-id: %s",
+ isis_print_nodeid(header_psnp->source_id));
packet_len -= (ISIS_COMMON_HEADER_SIZE+ISIS_PSNP_HEADER_SIZE);
pptr = p + (ISIS_COMMON_HEADER_SIZE+ISIS_PSNP_HEADER_SIZE);
@@ -1355,9 +1380,7 @@
break;
case TLV_ISNEIGH:
while (tmp >= ETHER_ADDR_LEN) {
- printf("\n\t\t\tIS Neighbor: ");
- if (!isis_print_sysid(tptr))
- return (1);
+ printf("\n\t\t\tIS Neighbor: %s",isis_print_sysid(tptr));
tmp -= ETHER_ADDR_LEN;
tptr += ETHER_ADDR_LEN;
}
@@ -1378,9 +1401,7 @@
printf(" Topology (0x%03x)",
ISIS_MASK_MTID(EXTRACT_16BITS(tptr)));
tptr+=2;
- printf("\n\t\t\t IS Neighbor: ");
- if (!isis_print_nodeid(tptr))
- return (1);
+ printf("\n\t\t\t IS Neighbor: %s", isis_print_nodeid(tptr));
tptr+=(SYSTEM_ID_LEN+1);
if (!TTEST2(*tptr, 3))
goto trunctlv;
@@ -1412,9 +1433,7 @@
while (tmp>0) {
if (!TTEST2(*tptr, SYSTEM_ID_LEN+1))
goto trunctlv;
- printf("\n\t\t\tIS Neighbor: ");
- if (!isis_print_nodeid(tptr))
- return (1);
+ printf("\n\t\t\tIS Neighbor: %s", isis_print_nodeid(tptr));
tptr+=(SYSTEM_ID_LEN+1);
if (!TTEST2(*tptr, 3))
@@ -1458,9 +1477,7 @@
if (!TTEST(*tlv_is_reach))
goto trunctlv;
- printf("\n\t\t\tIS Neighbor: ");
- isis_print_nodeid(tlv_is_reach->neighbor_nodeid);
-
+ printf("\n\t\t\tIS Neighbor: %s",
+isis_print_nodeid(tlv_is_reach->neighbor_nodeid));
printf(", Default Metric: %d, %s",
ISIS_LSP_TLV_METRIC_VALUE(tlv_is_reach->metric_default),
ISIS_LSP_TLV_METRIC_IE(tlv_is_reach->metric_default) ?
"External" : "Internal");
@@ -1742,8 +1759,8 @@
if(tmp>=6) {
if (!TTEST2(tlv_ptp_adj->neighbor_sysid, 6))
goto trunctlv;
- printf("\n\t\t\tNeighbor SystemID: ");
- isis_print_sysid(tlv_ptp_adj->neighbor_sysid);
+ printf("\n\t\t\tNeighbor SystemID: %s",
+ isis_print_sysid(tlv_ptp_adj->neighbor_sysid));
tmp-=6;
}
if(tmp>=4) {
@@ -1798,9 +1815,7 @@
case TLV_SHARED_RISK_GROUP:
if (!TTEST2(*tptr, 7))
goto trunctlv;
- printf("\n\t\t\tIS Neighbor: ");
- if (!isis_print_nodeid(tptr))
- return (1);
+ printf("\n\t\t\tIS Neighbor: %s", isis_print_nodeid(tptr));
tptr+=(SYSTEM_ID_LEN+1);
len-=(SYSTEM_ID_LEN+1);
@@ -1833,9 +1848,8 @@
case TLV_LSP:
tlv_lsp = (const struct isis_tlv_lsp *)tptr;
while(tmp>0) {
- printf("\n\t\t\tlsp-id: ");
- if (!isis_print_nodeid(tlv_lsp->lsp_id))
- return (1);
+ printf("\n\t\t\tlsp-id: %s",
+ isis_print_nodeid(tlv_lsp->lsp_id));
if (!TTEST((tlv_lsp->lsp_id)[SYSTEM_ID_LEN+1]))
goto trunctlv;
printf("-%02x",(tlv_lsp->lsp_id)[SYSTEM_ID_LEN+1]);
@@ -1858,7 +1872,7 @@
goto trunctlv;
printf("\n\t\t\tchecksum: 0x%04x",
EXTRACT_16BITS(tptr));
- if (osi_cksum(optr, length, off))
+ if (osi_cksum(optr, length))
printf(" (incorrect)");
else
printf(" (correct)");
@@ -1909,6 +1923,7 @@
case TLV_PART_DIS:
case TLV_SUMMARY:
case TLV_LSP_BUFFERSIZE:
+ case TLV_IS_ALIAS_ID:
case TLV_DECNET_PHASE4:
case TLV_LUCENT_PRIVATE:
case TLV_IDRP_INFO:
@@ -1946,19 +1961,19 @@
*/
static int
-osi_cksum(register const u_char *p, register u_int len, u_char *off)
+osi_cksum(const u_char *tptr, u_int len)
{
int32_t c0 = 0, c1 = 0;
- if ((off[0] == 0) && (off[1] == 0))
- return 0;
-
- off[0] = off[1] = 0;
while ((int)--len >= 0) {
- c0 += *p++;
+ c0 += *tptr++;
c0 %= 255;
c1 += c0;
c1 %= 255;
}
return (c0 | c1);
}
+
+
+
+
