Revert partially the commit 21b1273

[tcpdump] / netdissect.c

diff --git a/netdissect.c b/netdissect.c
index 08a3280c43dc0e2463c07f8930ea5bfdd8f47ea0..7e46d6aa3d3176ede396fefee8c788d7a053db03 100644 (file)
--- a/netdissect.c
+++ b/netdissect.c
@@ -30,6 +30,7 @@
 #include "netdissect.h"
 #include <string.h>
 #include <stdio.h>
+#include <stdlib.h>
 
 #ifdef USE_LIBSMI
 #include <smi.h>
@@ -122,14 +123,14 @@ nd_load_smi_module(const char *module, char *errbuf, size_t errbuf_size)
 {
 #ifdef USE_LIBSMI
        if (smiLoadModule(module) == 0) {
-               nd_snprintf(errbuf, errbuf_size, "could not load MIB module %s",
+               snprintf(errbuf, errbuf_size, "could not load MIB module %s",
                    module);
                return (-1);
        }
        nd_smi_module_loaded = 1;
        return (0);
 #else
-       nd_snprintf(errbuf, errbuf_size, "MIB module %s not loaded: no libsmi support",
+       snprintf(errbuf, errbuf_size, "MIB module %s not loaded: no libsmi support",
            module);
        return (-1);
 #endif
@@ -150,40 +151,86 @@ int
 nd_push_buffer(netdissect_options *ndo, u_char *new_buffer,
     const u_char *new_packetp, const u_char *new_snapend)
 {
-       struct netdissect_saved_info *ndsi;
+       struct netdissect_saved_packet_info *ndspi;
 
-       ndsi = (struct netdissect_saved_info *)malloc(sizeof(struct netdissect_saved_info));
-       if (ndsi == NULL)
+       ndspi = (struct netdissect_saved_packet_info *)malloc(sizeof(struct netdissect_saved_packet_info));
+       if (ndspi == NULL)
                return (0);     /* fail */
-       ndsi->ndsi_buffer = new_buffer;
-       ndsi->ndsi_packetp = ndo->ndo_packetp;
-       ndsi->ndsi_snapend = ndo->ndo_snapend;
-       ndsi->ndsi_prev = ndo->ndo_buffer_stack;
+       ndspi->ndspi_buffer = new_buffer;
+       ndspi->ndspi_packetp = ndo->ndo_packetp;
+       ndspi->ndspi_snapend = ndo->ndo_snapend;
+       ndspi->ndspi_prev = ndo->ndo_packet_info_stack;
 
        ndo->ndo_packetp = new_packetp;
        ndo->ndo_snapend = new_snapend;
-       ndo->ndo_buffer_stack = ndsi;
+       ndo->ndo_packet_info_stack = ndspi;
 
        return (1);     /* success */
 }
 
+/*
+ * Set a new snapshot end to the minimum of the existing snapshot end
+ * and the new snapshot end.
+ */
+int
+nd_push_snapend(netdissect_options *ndo, const u_char *new_snapend)
+{
+       struct netdissect_saved_packet_info *ndspi;
+
+       ndspi = (struct netdissect_saved_packet_info *)malloc(sizeof(struct netdissect_saved_packet_info));
+       if (ndspi == NULL)
+               return (0);     /* fail */
+       ndspi->ndspi_buffer = NULL;     /* no new buffer */
+       ndspi->ndspi_packetp = ndo->ndo_packetp;
+       ndspi->ndspi_snapend = ndo->ndo_snapend;
+       ndspi->ndspi_prev = ndo->ndo_packet_info_stack;
+
+       /* No new packet pointer, either */
+       if (new_snapend < ndo->ndo_snapend)
+               ndo->ndo_snapend = new_snapend;
+       ndo->ndo_packet_info_stack = ndspi;
+
+       return (1);     /* success */
+}
+
+/*
+ * Change an already-pushed snapshot end.  This may increase the
+ * snapshot end, as it may be used, for example, for a Jumbo Payload
+ * option in IPv6.  It must not increase it past the snapshot length
+ * atop which the current one was pushed, however.
+ */
+void
+nd_change_snapend(netdissect_options *ndo, const u_char *new_snapend)
+{
+       struct netdissect_saved_packet_info *ndspi;
+
+       ndspi = ndo->ndo_packet_info_stack;
+       if (ndspi->ndspi_prev != NULL) {
+               if (new_snapend <= ndspi->ndspi_prev->ndspi_snapend)
+                       ndo->ndo_snapend = new_snapend;
+       } else {
+               if (new_snapend < ndo->ndo_snapend)
+                       ndo->ndo_snapend = new_snapend;
+       }
+}
+
 void
-nd_pop_buffer(netdissect_options *ndo)
+nd_pop_packet_info(netdissect_options *ndo)
 {
-       struct netdissect_saved_info *ndsi;
+       struct netdissect_saved_packet_info *ndspi;
 
-       ndsi = ndo->ndo_buffer_stack;
-       ndo->ndo_packetp = ndsi->ndsi_packetp;
-       ndo->ndo_snapend = ndsi->ndsi_snapend;
-       ndo->ndo_buffer_stack = ndsi->ndsi_prev;
+       ndspi = ndo->ndo_packet_info_stack;
+       ndo->ndo_packetp = ndspi->ndspi_packetp;
+       ndo->ndo_snapend = ndspi->ndspi_snapend;
+       ndo->ndo_packet_info_stack = ndspi->ndspi_prev;
 
-       free(ndsi->ndsi_buffer);
-       free(ndsi);
+       free(ndspi->ndspi_buffer);
+       free(ndspi);
 }
 
 void
-nd_pop_all_buffers(netdissect_options *ndo)
+nd_pop_all_packet_info(netdissect_options *ndo)
 {
-       while (ndo->ndo_buffer_stack != NULL)
-               nd_pop_buffer(ndo);
+       while (ndo->ndo_packet_info_stack != NULL)
+               nd_pop_packet_info(ndo);
 }