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Diffstat (limited to 'plugins/check_dns.c')
-rw-r--r--plugins/check_dns.c81
1 files changed, 62 insertions, 19 deletions
diff --git a/plugins/check_dns.c b/plugins/check_dns.c
index b90f50e6..9de6caf5 100644
--- a/plugins/check_dns.c
+++ b/plugins/check_dns.c
@@ -41,7 +41,7 @@ const char *email = "devel@monitoring-plugins.org";
int process_arguments (int, char **);
int validate_arguments (void);
-int error_scan (char *);
+int error_scan (char *, int *);
int ip_match_cidr(const char *, const char *);
unsigned long ip2long(const char *);
void print_help (void);
@@ -54,6 +54,7 @@ char ptr_server[ADDRESS_LENGTH] = "";
int verbose = FALSE;
char **expected_address = NULL;
int expected_address_cnt = 0;
+int expect_nxdomain = FALSE;
int expect_authority = FALSE;
int all_match = FALSE;
@@ -87,6 +88,7 @@ main (int argc, char **argv)
int parse_address = FALSE; /* This flag scans for Address: but only after Name: */
output chld_out, chld_err;
size_t i;
+ int is_nxdomain = FALSE;
setlocale (LC_ALL, "");
bindtextdomain (PACKAGE, LOCALEDIR);
@@ -186,7 +188,7 @@ main (int argc, char **argv)
}
- result = error_scan (chld_out.line[i]);
+ result = error_scan (chld_out.line[i], &is_nxdomain);
if (result != STATE_OK) {
msg = strchr (chld_out.line[i], ':');
if(msg) msg++;
@@ -199,8 +201,8 @@ main (int argc, char **argv)
if (verbose)
puts(chld_err.line[i]);
- if (error_scan (chld_err.line[i]) != STATE_OK) {
- result = max_state (result, error_scan (chld_err.line[i]));
+ if (error_scan (chld_err.line[i], &is_nxdomain) != STATE_OK) {
+ result = max_state (result, error_scan (chld_err.line[i], &is_nxdomain));
msg = strchr(input_buffer, ':');
if(msg)
msg++;
@@ -209,6 +211,10 @@ main (int argc, char **argv)
}
}
+ if (is_nxdomain && !expect_nxdomain) {
+ die (STATE_CRITICAL, _("Domain '%s' was not found by the server\n"), query_address);
+ }
+
if (addresses) {
int i,slen;
char *adrp;
@@ -260,6 +266,16 @@ main (int argc, char **argv)
}
}
+ if (expect_nxdomain) {
+ if (!is_nxdomain) {
+ result = STATE_CRITICAL;
+ xasprintf(&msg, _("Domain '%s' was found by the server: '%s'\n"), query_address, address);
+ } else {
+ if (address != NULL) free(address);
+ address = "NXDOMAIN";
+ }
+ }
+
/* check if authoritative */
if (result == STATE_OK && expect_authority && non_authoritative) {
result = STATE_CRITICAL;
@@ -339,9 +355,15 @@ ip2long(const char* src) {
}
int
-error_scan (char *input_buffer)
+error_scan (char *input_buffer, int *is_nxdomain)
{
+ const int nxdomain = strstr (input_buffer, "Non-existent") ||
+ strstr (input_buffer, "** server can't find") ||
+ strstr (input_buffer, "** Can't find") ||
+ strstr (input_buffer, "NXDOMAIN");
+ if (nxdomain) *is_nxdomain = TRUE;
+
/* the DNS lookup timed out */
if (strstr (input_buffer, _("Note: nslookup is deprecated and may be removed from future releases.")) ||
strstr (input_buffer, _("Consider using the `dig' or `host' programs instead. Run nslookup with")) ||
@@ -360,7 +382,7 @@ error_scan (char *input_buffer)
/* Connection was refused */
else if (strstr (input_buffer, "Connection refused") ||
- strstr (input_buffer, "Couldn't find server") ||
+ strstr (input_buffer, "Couldn't find server") ||
strstr (input_buffer, "Refused") ||
(strstr (input_buffer, "** server can't find") &&
strstr (input_buffer, ": REFUSED")))
@@ -374,13 +396,6 @@ error_scan (char *input_buffer)
else if (strstr (input_buffer, "No information"))
die (STATE_CRITICAL, _("No information returned by DNS server at %s\n"), dns_server);
- /* Host or domain name does not exist */
- else if (strstr (input_buffer, "Non-existent") ||
- strstr (input_buffer, "** server can't find") ||
- strstr (input_buffer, "** Can't find") ||
- strstr (input_buffer,"NXDOMAIN"))
- die (STATE_CRITICAL, _("Domain %s was not found by the server\n"), query_address);
-
/* Network is unreachable */
else if (strstr (input_buffer, "Network is unreachable"))
die (STATE_CRITICAL, _("Network is unreachable\n"));
@@ -417,6 +432,7 @@ process_arguments (int argc, char **argv)
{"server", required_argument, 0, 's'},
{"reverse-server", required_argument, 0, 'r'},
{"expected-address", required_argument, 0, 'a'},
+ {"expect-nxdomain", no_argument, 0, 'n'},
{"expect-authority", no_argument, 0, 'A'},
{"all", no_argument, 0, 'L'},
{"warning", required_argument, 0, 'w'},
@@ -432,7 +448,7 @@ process_arguments (int argc, char **argv)
strcpy (argv[c], "-t");
while (1) {
- c = getopt_long (argc, argv, "hVvALt:H:s:r:a:w:c:", long_opts, &opt_index);
+ c = getopt_long (argc, argv, "hVvALnt:H:s:r:a:w:c:", long_opts, &opt_index);
if (c == -1 || c == EOF)
break;
@@ -473,9 +489,26 @@ process_arguments (int argc, char **argv)
case 'a': /* expected address */
if (strlen (optarg) >= ADDRESS_LENGTH)
die (STATE_UNKNOWN, _("Input buffer overflow\n"));
- expected_address = (char **)realloc(expected_address, (expected_address_cnt+1) * sizeof(char**));
- expected_address[expected_address_cnt] = strdup(optarg);
- expected_address_cnt++;
+ if (strchr(optarg, ',') != NULL) {
+ char *comma = strchr(optarg, ',');
+ while (comma != NULL) {
+ expected_address = (char **)realloc(expected_address, (expected_address_cnt+1) * sizeof(char**));
+ expected_address[expected_address_cnt] = strndup(optarg, comma - optarg);
+ expected_address_cnt++;
+ optarg = comma + 1;
+ comma = strchr(optarg, ',');
+ }
+ expected_address = (char **)realloc(expected_address, (expected_address_cnt+1) * sizeof(char**));
+ expected_address[expected_address_cnt] = strdup(optarg);
+ expected_address_cnt++;
+ } else {
+ expected_address = (char **)realloc(expected_address, (expected_address_cnt+1) * sizeof(char**));
+ expected_address[expected_address_cnt] = strdup(optarg);
+ expected_address_cnt++;
+ }
+ break;
+ case 'n': /* expect NXDOMAIN */
+ expect_nxdomain = TRUE;
break;
case 'A': /* expect authority */
expect_authority = TRUE;
@@ -518,8 +551,15 @@ process_arguments (int argc, char **argv)
int
validate_arguments ()
{
- if (query_address[0] == 0)
+ if (query_address[0] == 0) {
+ printf ("missing --host argument\n");
return ERROR;
+ }
+
+ if (expected_address_cnt > 0 && expect_nxdomain) {
+ printf ("--expected-address and --expect-nxdomain cannot be combined\n");
+ return ERROR;
+ }
return OK;
}
@@ -552,6 +592,9 @@ print_help (void)
printf (" %s\n", _("Optional IP-ADDRESS/CIDR you expect the DNS server to return. HOST must end"));
printf (" %s\n", _("with a dot (.). This option can be repeated multiple times (Returns OK if any"));
printf (" %s\n", _("value matches)."));
+ printf (" -n, --expect-nxdomain\n");
+ printf (" %s\n", _("Expect the DNS server to return NXDOMAIN (i.e. the domain was not found)"));
+ printf (" %s\n", _("Cannot be used together with -a"));
printf (" -A, --expect-authority\n");
printf (" %s\n", _("Optionally expect the DNS server to be authoritative for the lookup"));
printf (" -w, --warning=seconds\n");
@@ -572,5 +615,5 @@ void
print_usage (void)
{
printf ("%s\n", _("Usage:"));
- printf ("%s -H host [-s server] [-a expected-address] [-A] [-t timeout] [-w warn] [-c crit] [-L]\n", progname);
+ printf ("%s -H host [-s server] [-a expected-address] [-n] [-A] [-t timeout] [-w warn] [-c crit] [-L]\n", progname);
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-22 00:26:43 +0000