ndrdump: add --stop-on-parse-failure

If a data stream fails to parse as an NDR object, the default ndrdump
action is to try to print those structures anyway, resulting perhaps in
a NULL dereference. Sometimes you don't want to see that because it isn't
very interesting and makes it harder to distinguish a crash in the parse
routines. So --stop-on-parse-failure will skip the print and validate
stages altogether if the parse failed.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Pair-programmed-with: Andrew Bartlett <abartlet@samba.org>

diff --git a/librpc/tools/ndrdump.c b/librpc/tools/ndrdump.c
index bd4f277607b26beb72a69d4e8e5cdf8df185ab96..a8f1969a2d401a2acd0cb267ef44ed83d74e87c1 100644 (file)
--- a/librpc/tools/ndrdump.c
+++ b/librpc/tools/ndrdump.c
@@ -261,8 +261,18 @@ static void ndr_print_dummy(struct ndr_print *ndr, const char *format, ...)
        bool assume_ndr64 = false;
        bool quiet = false;
        bool hex_input = false;
+       bool stop_on_parse_failure = false;
        int opt;
-       enum {OPT_CONTEXT_FILE=1000, OPT_VALIDATE, OPT_DUMP_DATA, OPT_LOAD_DSO, OPT_NDR64, OPT_QUIET, OPT_HEX_INPUT};
+       enum {
+               OPT_CONTEXT_FILE=1000,
+               OPT_VALIDATE,
+               OPT_DUMP_DATA,
+               OPT_LOAD_DSO,
+               OPT_NDR64,
+               OPT_QUIET,
+               OPT_HEX_INPUT,
+               OPT_STOP_ON_PARSE_FAILURE,
+       };
        struct poptOption long_options[] = {
                POPT_AUTOHELP
                {"context-file", 'c', POPT_ARG_STRING, NULL, OPT_CONTEXT_FILE, "In-filename to parse first", "CTX-FILE" },
@@ -272,6 +282,8 @@ static void ndr_print_dummy(struct ndr_print *ndr, const char *format, ...)
                {"ndr64", 0, POPT_ARG_NONE, NULL, OPT_NDR64, "Assume NDR64 data", NULL },
                {"quiet", 0, POPT_ARG_NONE, NULL, OPT_QUIET, "Don't actually dump anything", NULL },
                {"hex-input", 0, POPT_ARG_NONE, NULL, OPT_HEX_INPUT, "Read the input file in as a hex dump", NULL },
+               {"stop-on-parse-failure", 0, POPT_ARG_NONE, NULL, OPT_STOP_ON_PARSE_FAILURE,
+                "Do not try to print structures that fail to parse.", NULL },
                POPT_COMMON_SAMBA
                POPT_COMMON_VERSION
                { NULL }
@@ -316,6 +328,9 @@ static void ndr_print_dummy(struct ndr_print *ndr, const char *format, ...)
                case OPT_HEX_INPUT:
                        hex_input = true;
                        break;
+               case OPT_STOP_ON_PARSE_FAILURE:
+                       stop_on_parse_failure = true;
+                       break;
                }
        }
 
@@ -509,6 +524,11 @@ static void ndr_print_dummy(struct ndr_print *ndr, const char *format, ...)
 
        printf("pull returned %s\n", nt_errstr(status));
 
+       if (stop_on_parse_failure  && !NT_STATUS_IS_OK(status)) {
+               printf("not printing because --stop-on-parse-failure\n");
+               exit(1);
+       }
+
        if (ndr_pull->offset > ndr_pull->relative_highest_offset) {
                highest_ofs = ndr_pull->offset;
        } else {