Avoid collison with error(), clean up code a bit.

[tcpdump] / print-nflog.c

diff --git a/print-nflog.c b/print-nflog.c
index 238226e13a384ed1130becbe6bfcb771a2275bca..a29b930cb30f25ea4c01a57cc34efb9c1208a484 100644 (file)
--- a/print-nflog.c
+++ b/print-nflog.c
@@ -31,31 +31,22 @@
 
 #include <tcpdump-stdinc.h>
 
 
 #include <tcpdump-stdinc.h>
 

-#include <stdio.h>
-#include <pcap.h>
-
-#include "netdissect.h"

 #include "interface.h"
 
 #include "interface.h"
 

-#include "nflog.h"
-
-#ifdef DLT_NFLOG
+#if defined(DLT_NFLOG) && defined(HAVE_PCAP_NFLOG_H)
+#include <pcap/nflog.h>

 
 

-#define NFULA_PAYLOAD 9
-#define NFULA_MAX 17
-
-const struct tok nflog_values[] = {
+static const struct tok nflog_values[] = {

        { AF_INET,              "IPv4" },
        { AF_INET,              "IPv4" },

+#ifdef INET6

        { AF_INET6,             "IPv6" },
        { AF_INET6,             "IPv6" },

-       { 0,                            NULL }
+#endif /*INET6*/
+       { 0,                    NULL }

 };
 
 static inline void
 };
 
 static inline void

-nflog_hdr_print(struct netdissect_options *ndo, const u_char *bp, u_int length)
+nflog_hdr_print(netdissect_options *ndo, const nflog_hdr_t *hdr, u_int length)

 {
 {

-       const nflog_hdr_t *hdr;
-       hdr = (const nflog_hdr_t *)bp;
-

        ND_PRINT((ndo, "version %d, resource ID %d", hdr->nflog_version, ntohs(hdr->nflog_rid)));
 
        if (!ndo->ndo_qflag) {
        ND_PRINT((ndo, "version %d, resource ID %d", hdr->nflog_version, ntohs(hdr->nflog_rid)));
 
        if (!ndo->ndo_qflag) {


@@ -73,82 +64,103 @@ nflog_hdr_print(struct netdissect_options *ndo, const u_char *bp, u_int length)
        ND_PRINT((ndo, ", length %u: ", length));
 }
 
        ND_PRINT((ndo, ", length %u: ", length));
 }
 

-static void
-nflog_print(struct netdissect_options *ndo, const u_char *p, u_int length, u_int caplen)
+u_int
+nflog_if_print(netdissect_options *ndo,
+                          const struct pcap_pkthdr *h, const u_char *p)

 {
 {

-       const nflog_hdr_t *hdr;
+       const nflog_hdr_t *hdr = (const nflog_hdr_t *)p;

        const nflog_tlv_t *tlv;
        const nflog_tlv_t *tlv;

-       u_int16_t size;
+       uint16_t size;
+       uint16_t h_size = sizeof(nflog_hdr_t);
+       u_int caplen = h->caplen;
+       u_int length = h->len;

 
 

-       if (caplen < (int) sizeof(nflog_hdr_t)) {
+       if (caplen < (int) sizeof(nflog_hdr_t) || length < (int) sizeof(nflog_hdr_t)) {

                ND_PRINT((ndo, "[|nflog]"));
                ND_PRINT((ndo, "[|nflog]"));

-               return;
+               return h_size;
+       }
+
+       if (!(hdr->nflog_version) == 0) {
+               ND_PRINT((ndo, "version %u (unknown)", hdr->nflog_version));
+               return h_size;

        }
 
        if (ndo->ndo_eflag)
        }
 
        if (ndo->ndo_eflag)

-               nflog_hdr_print(ndo, p, length);
+               nflog_hdr_print(ndo, hdr, length);

 
 

+       p += sizeof(nflog_hdr_t);

        length -= sizeof(nflog_hdr_t);
        caplen -= sizeof(nflog_hdr_t);
        length -= sizeof(nflog_hdr_t);
        caplen -= sizeof(nflog_hdr_t);

-       hdr = (const nflog_hdr_t *)p;
-       p += sizeof(nflog_hdr_t);

 
 

-       do {
+       while (length > 0) {
+               /* We have some data.  Do we have enough for the TLV header? */
+               if (caplen < sizeof(nflog_tlv_t) || length < sizeof(nflog_tlv_t)) {
+                       /* No. */
+                       ND_PRINT((ndo, "[|nflog]"));
+                       return h_size;
+               }
+

                tlv = (const nflog_tlv_t *) p;
                size = tlv->tlv_length;
                tlv = (const nflog_tlv_t *) p;
                size = tlv->tlv_length;

-
-               /* wrong size of the packet */
-               if (size > length )
-                       return;
-
-               /* wrong tlv type */
-               if (tlv->tlv_type > NFULA_MAX)
-                       return;
-

                if (size % 4 != 0)
                        size += 4 - size % 4;
 
                if (size % 4 != 0)
                        size += 4 - size % 4;
 

-               p += size;
-               length = length - size;
-               caplen = caplen - size;
+               /* Is the TLV's length less than the minimum? */
+               if (size < sizeof(nflog_tlv_t)) {
+                       /* Yes. Give up now. */
+                       ND_PRINT((ndo, "[|nflog]"));
+                       return h_size;
+               }
+
+               /* Do we have enough data for the full TLV? */
+               if (caplen < size || length < size) {
+                       /* No. */
+                       ND_PRINT((ndo, "[|nflog]"));
+                       return h_size;
+               }

 
 

-       } while (tlv->tlv_type != NFULA_PAYLOAD);
+               if (tlv->tlv_type == NFULA_PAYLOAD) {
+                       /*
+                        * This TLV's data is the packet payload.
+                        * Skip past the TLV header, and break out
+                        * of the loop so we print the packet data.
+                        */
+                       p += sizeof(nflog_tlv_t);
+                       h_size += sizeof(nflog_tlv_t);
+                       length -= sizeof(nflog_tlv_t);
+                       caplen -= sizeof(nflog_tlv_t);
+                       break;
+               }

 
 

-       /* dont skip payload just tlv length and type */
-       p = p - size + 4;
-       length += size - 4;
-       caplen += size - 4;
+               p += size;
+               h_size += size;
+               length -= size;
+               caplen -= size;
+       }

 
        switch (hdr->nflog_family) {
 
        case AF_INET:
 
        switch (hdr->nflog_family) {
 
        case AF_INET:

-                       ip_print(ndo, p, length);
+               ip_print(ndo, p, length);

                break;
 
                break;
 

-#ifdef INET6
+#ifdef AF_INET6

        case AF_INET6:
                ip6_print(ndo, p, length);
                break;
        case AF_INET6:
                ip6_print(ndo, p, length);
                break;

-#endif /*INET6*/
+#endif /* AF_INET6 */

 
        default:
                if (!ndo->ndo_eflag)
 
        default:
                if (!ndo->ndo_eflag)

-                       nflog_hdr_print(ndo, (u_char *)hdr,
+                       nflog_hdr_print(ndo, hdr,

                                length + sizeof(nflog_hdr_t));
 
                if (!ndo->ndo_suppress_default_print)
                                length + sizeof(nflog_hdr_t));
 
                if (!ndo->ndo_suppress_default_print)

-                       ndo->ndo_default_print(ndo, p, caplen);
+                       ND_DEFAULTPRINT(p, caplen);

                break;
        }
                break;
        }

-}
-
-u_int
-nflog_if_print(struct netdissect_options *ndo,
-                          const struct pcap_pkthdr *h, const u_char *p)
-{

 
 

-       nflog_print(ndo, p, h->len, h->caplen);
-       return (sizeof(nflog_hdr_t));
+       return h_size;

 }
 
 }
 

-#endif /* DLT_NFLOG */
+#endif /* defined(DLT_NFLOG) && defined(HAVE_PCAP_NFLOG_H) */