]> The Tcpdump Group git mirrors - tcpdump/blobdiff - print-vjc.c
NTP: Use tstr for truncation indicator.
[tcpdump] / print-vjc.c
index 43eae996af47c9f391f9d34494460361dae23ab7..3287b9bcf789889d42dc47854d2ccd08f65606bb 100644 (file)
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  */
 
+/* \summary: PPP Van Jacobson compression printer */
+
+/* specification: RFC 1144 */
+
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
-#include <tcpdump-stdinc.h>
-
-#include <pcap.h>
-#include <stdio.h>
-
-#include "interface.h"
-#include "addrtoname.h"
+#include <netdissect-stdinc.h>
 
+#include "netdissect.h"
 #include "slcompress.h"
 #include "ppp.h"
 
  * We therefore leave "proto" - which is the PPP protocol type - in place,
  * *not* marked as unused, for now, so that GCC warnings about the
  * unused argument remind us that we should fix this some day.
+ *
+ * XXX - also, it fetches the TCP checksum field in COMPRESSED_TCP
+ * packets directly, rather than with EXTRACT_16BITS(); RFC 1144 says
+ * it's "the unmodified TCP checksum", which would imply that it's
+ * big-endian, but perhaps, on the platform where this was developed,
+ * the packets were munged by the networking stack before being handed
+ * to the packet capture mechanism.
  */
 int
-vjc_print(register const char *bp, u_short proto _U_)
+vjc_print(netdissect_options *ndo, register const char *bp, u_short proto _U_)
 {
        int i;
 
        switch (bp[0] & 0xf0) {
        case TYPE_IP:
-               if (eflag)
-                       printf("(vjc type=IP) ");
+               if (ndo->ndo_eflag)
+                       ND_PRINT((ndo, "(vjc type=IP) "));
                return PPP_IP;
        case TYPE_UNCOMPRESSED_TCP:
-               if (eflag)
-                       printf("(vjc type=raw TCP) ");
+               if (ndo->ndo_eflag)
+                       ND_PRINT((ndo, "(vjc type=raw TCP) "));
                return PPP_IP;
        case TYPE_COMPRESSED_TCP:
-               if (eflag)
-                       printf("(vjc type=compressed TCP) ");
+               if (ndo->ndo_eflag)
+                       ND_PRINT((ndo, "(vjc type=compressed TCP) "));
                for (i = 0; i < 8; i++) {
                        if (bp[1] & (0x80 >> i))
-                               printf("%c", "?CI?SAWU"[i]);
+                               ND_PRINT((ndo, "%c", "?CI?SAWU"[i]));
                }
                if (bp[1])
-                       printf(" ");
-               printf("C=0x%02x ", bp[2]);
-               printf("sum=0x%04x ", *(u_short *)&bp[3]);
+                       ND_PRINT((ndo, " "));
+               ND_PRINT((ndo, "C=0x%02x ", bp[2]));
+               ND_PRINT((ndo, "sum=0x%04x ", *(const u_short *)&bp[3]));
                return -1;
        case TYPE_ERROR:
-               if (eflag)
-                       printf("(vjc type=error) ");
+               if (ndo->ndo_eflag)
+                       ND_PRINT((ndo, "(vjc type=error) "));
                return -1;
        default:
-               if (eflag)
-                       printf("(vjc type=0x%02x) ", bp[0] & 0xf0);
+               if (ndo->ndo_eflag)
+                       ND_PRINT((ndo, "(vjc type=0x%02x) ", bp[0] & 0xf0));
                return -1;
        }
 }