* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
-#ifndef lint
-static const char rcsid[] =
- "@(#) $Header: /tcpdump/master/tcpdump/print-chdlc.c,v 1.21 2002-10-18 20:08:34 hannes Exp $ (LBL)";
-#endif
+/* \summary: Cisco HDLC printer */
#ifdef HAVE_CONFIG_H
-#include "config.h"
+#include <config.h>
#endif
-#include <tcpdump-stdinc.h>
-
-#include <pcap.h>
-#include <stdio.h>
+#include "netdissect-stdinc.h"
-#include "interface.h"
+#include "netdissect.h"
#include "addrtoname.h"
#include "ethertype.h"
#include "extract.h"
-#include "ppp.h"
#include "chdlc.h"
+#include "nlpid.h"
+
+static void chdlc_slarp_print(netdissect_options *, const u_char *, u_int);
+
+static const struct tok chdlc_cast_values[] = {
+ { CHDLC_UNICAST, "unicast" },
+ { CHDLC_BCAST, "bcast" },
+ { 0, NULL}
+};
-static void chdlc_slarp_print(const u_char *, u_int);
/* Standard CHDLC printer */
-void
-chdlc_if_print(u_char *user _U_, const struct pcap_pkthdr *h,
- register const u_char *p)
+u_int
+chdlc_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p)
{
- register u_int length = h->len;
- register u_int caplen = h->caplen;
-
- ++infodelay;
- ts_print(&h->ts);
-
- /*
- * Some printers want to get back at the link level addresses,
- * and/or check that they're not walking off the end of the packet.
- * Rather than pass them all the way down, we set these globals.
- */
- packetp = p;
- snapend = p + caplen;
-
- chdlc_print(p, length, caplen);
-
- putchar('\n');
- --infodelay;
- if (infoprint)
- info(0);
+ ndo->ndo_protocol = "chdlc_if";
+ return chdlc_print(ndo, p, h->len);
}
-void
-chdlc_print(register const u_char *p, u_int length, u_int caplen)
+u_int
+chdlc_print(netdissect_options *ndo, const u_char *p, u_int length)
{
- const struct ip *ip;
u_int proto;
-
- if (caplen < CHDLC_HDRLEN) {
- printf("[|chdlc]");
- return;
- }
-
- proto = EXTRACT_16BITS(&p[2]);
- if (eflag) {
- switch (p[0]) {
- case CHDLC_UNICAST:
- printf("unicast ");
- break;
- case CHDLC_BCAST:
- printf("bcast ");
- break;
- default:
- printf("0x%02x ", p[0]);
- break;
- }
- printf("%d %04x: ", length, proto);
+ const u_char *bp = p;
+
+ ndo->ndo_protocol = "chdlc";
+ if (length < CHDLC_HDRLEN)
+ goto trunc;
+ ND_TCHECK_LEN(p, CHDLC_HDRLEN);
+ proto = GET_BE_U_2(p + 2);
+ if (ndo->ndo_eflag) {
+ ND_PRINT("%s, ethertype %s (0x%04x), length %u: ",
+ tok2str(chdlc_cast_values, "0x%02x", GET_U_1(p)),
+ tok2str(ethertype_values, "Unknown", proto),
+ proto,
+ length);
}
length -= CHDLC_HDRLEN;
- ip = (const struct ip *)(p + CHDLC_HDRLEN);
+ p += CHDLC_HDRLEN;
+
switch (proto) {
case ETHERTYPE_IP:
- ip_print((const u_char *)ip, length);
+ ip_print(ndo, p, length);
break;
-#ifdef INET6
case ETHERTYPE_IPV6:
- ip6_print((const u_char *)ip, length);
+ ip6_print(ndo, p, length);
break;
-#endif
case CHDLC_TYPE_SLARP:
- chdlc_slarp_print((const u_char *)ip, length);
+ chdlc_slarp_print(ndo, p, length);
break;
#if 0
case CHDLC_TYPE_CDP:
- chdlc_cdp_print((const u_char *)ip, length);
+ chdlc_cdp_print(p, length);
break;
#endif
case ETHERTYPE_MPLS:
case ETHERTYPE_MPLS_MULTI:
- mpls_print((const u_char *)(ip), length);
+ mpls_print(ndo, p, length);
break;
case ETHERTYPE_ISO:
- /* is the fudge byte set ? if yes lets skip a byte */
- if (*(p+CHDLC_HDRLEN) == 0)
- isoclns_print(p+CHDLC_HDRLEN+1, length-1, length-1, NULL, NULL);
+ /* is the fudge byte set ? lets verify by spotting ISO headers */
+ if (length < 2)
+ goto trunc;
+ ND_TCHECK_2(p);
+ if (GET_U_1(p + 1) == NLPID_CLNP ||
+ GET_U_1(p + 1) == NLPID_ESIS ||
+ GET_U_1(p + 1) == NLPID_ISIS)
+ isoclns_print(ndo, p + 1, length - 1);
else
- isoclns_print(p+CHDLC_HDRLEN, length, length, NULL, NULL);
+ isoclns_print(ndo, p, length);
break;
default:
- printf("unknown CHDLC protocol (0x%04x)", proto);
+ if (!ndo->ndo_eflag)
+ ND_PRINT("unknown CHDLC protocol (0x%04x)", proto);
break;
}
- if (xflag)
- default_print((const u_char *)ip, caplen - CHDLC_HDRLEN);
+
+ return (CHDLC_HDRLEN);
+
+trunc:
+ nd_print_trunc(ndo);
+ return (ND_BYTES_AVAILABLE_AFTER(bp));
}
+/*
+ * The fixed-length portion of a SLARP packet.
+ */
struct cisco_slarp {
- u_int32_t code;
+ nd_uint32_t code;
#define SLARP_REQUEST 0
#define SLARP_REPLY 1
#define SLARP_KEEPALIVE 2
union {
struct {
- struct in_addr addr;
- struct in_addr mask;
- u_int16_t unused[3];
+ uint8_t addr[4];
+ uint8_t mask[4];
} addr;
struct {
- u_int32_t myseq;
- u_int32_t yourseq;
- u_int16_t rel;
- u_int16_t t1;
- u_int16_t t2;
+ nd_uint32_t myseq;
+ nd_uint32_t yourseq;
+ nd_uint16_t rel;
} keep;
} un;
};
-#define SLARP_LEN 18
+#define SLARP_MIN_LEN 14
+#define SLARP_MAX_LEN 18
static void
-chdlc_slarp_print(const u_char *cp, u_int length)
+chdlc_slarp_print(netdissect_options *ndo, const u_char *cp, u_int length)
{
const struct cisco_slarp *slarp;
+ u_int sec,min,hrs,days;
- if (length < SLARP_LEN) {
- printf("[|slarp]");
- return;
- }
+ ndo->ndo_protocol = "chdlc_slarp";
+ ND_PRINT("SLARP (length: %u), ",length);
+ if (length < SLARP_MIN_LEN)
+ goto trunc;
slarp = (const struct cisco_slarp *)cp;
- printf("SLARP (length: %u), ",length);
- switch (ntohl(slarp->code)) {
+ ND_TCHECK_LEN(slarp, SLARP_MIN_LEN);
+ switch (GET_BE_U_4(slarp->code)) {
case SLARP_REQUEST:
- printf("request");
- /* ok we do not know it - but lets at least dump it */
- print_unknown_data(cp+4,"\n\t",length-4);
+ ND_PRINT("request");
+ /*
+ * At least according to William "Chops" Westfield's
+ * message in
+ *
+ * http://www.nethelp.no/net/cisco-hdlc.txt
+ *
+ * the address and mask aren't used in requests -
+ * they're just zero.
+ */
break;
case SLARP_REPLY:
- printf("reply %s/%s",
- ipaddr_string(&slarp->un.addr.addr),
- ipaddr_string(&slarp->un.addr.mask));
+ ND_PRINT("reply %s/%s",
+ ipaddr_string(ndo, slarp->un.addr.addr),
+ ipaddr_string(ndo, slarp->un.addr.mask));
break;
case SLARP_KEEPALIVE:
- printf("keepalive: mineseen=0x%08x yourseen=0x%08x ",
- (u_int32_t)ntohl(slarp->un.keep.myseq),
- (u_int32_t)ntohl(slarp->un.keep.yourseq));
- printf("reliability=0x%04x t1=%d.%d",
- ntohs(slarp->un.keep.rel), ntohs(slarp->un.keep.t1),
- ntohs(slarp->un.keep.t2));
+ ND_PRINT("keepalive: mineseen=0x%08x, yourseen=0x%08x, reliability=0x%04x",
+ GET_BE_U_4(slarp->un.keep.myseq),
+ GET_BE_U_4(slarp->un.keep.yourseq),
+ GET_BE_U_2(slarp->un.keep.rel));
+
+ if (length >= SLARP_MAX_LEN) { /* uptime-stamp is optional */
+ cp += SLARP_MIN_LEN;
+ ND_TCHECK_4(cp);
+ sec = GET_BE_U_4(cp) / 1000;
+ min = sec / 60; sec -= min * 60;
+ hrs = min / 60; min -= hrs * 60;
+ days = hrs / 24; hrs -= days * 24;
+ ND_PRINT(", link uptime=%ud%uh%um%us",days,hrs,min,sec);
+ }
break;
default:
- printf("0x%02x unknown", (u_int32_t)ntohl(slarp->code));
- if (vflag <= 1)
- print_unknown_data(cp+4,"\n\t",length-4);
+ ND_PRINT("0x%02x unknown", GET_BE_U_4(slarp->code));
+ if (ndo->ndo_vflag <= 1)
+ print_unknown_data(ndo,cp+4,"\n\t",length-4);
break;
}
- if (SLARP_LEN < length && vflag)
- printf(", (trailing junk: %d bytes)", length - SLARP_LEN);
- if (vflag > 1)
- print_unknown_data(cp+4,"\n\t",length-4);
+ if (SLARP_MAX_LEN < length && ndo->ndo_vflag)
+ ND_PRINT(", (trailing junk: %u bytes)", length - SLARP_MAX_LEN);
+ if (ndo->ndo_vflag > 1)
+ print_unknown_data(ndo,cp+4,"\n\t",length-4);
+ return;
+
+trunc:
+ nd_print_trunc(ndo);
}
projects / tcpdump / blobdiff