Module: monitoring-plugins
Branch: master
Commit: 65794e31374b3aa6e1f2c03d090b52e137df13e6
Author: Lorenz Kästle <12514511+rincewinds...@users.noreply.github.com>
Date: Sat Mar 8 13:05:57 2025 +0100
URL:
https://www.monitoring-plugins.org/repositories/monitoring-plugins/commit/?id=65794e31
Refactor check_dns
---
plugins/check_dns.c | 240 ++++++++++++++++++++++---------------------
plugins/check_dns.d/config.h | 34 ++++++
2 files changed, 158 insertions(+), 116 deletions(-)
diff --git a/plugins/check_dns.c b/plugins/check_dns.c
index b3d4a6e5..7071c01f 100644
--- a/plugins/check_dns.c
+++ b/plugins/check_dns.c
@@ -39,26 +39,22 @@ const char *email = "devel@monitoring-plugins.org";
#include "netutils.h"
#include "runcmd.h"
-static int process_arguments(int /*argc*/, char ** /*argv*/);
-static int validate_arguments(void);
-static int error_scan(char * /*input_buffer*/, bool *);
+#include "states.h"
+#include "check_dns.d/config.h"
+
+typedef struct {
+ int errorcode;
+ check_dns_config config;
+} check_dns_config_wrapper;
+static check_dns_config_wrapper process_arguments(int /*argc*/, char **
/*argv*/);
+static check_dns_config_wrapper validate_arguments(check_dns_config_wrapper
/*config_wrapper*/);
+static mp_state_enum error_scan(char * /*input_buffer*/, bool *
/*is_nxdomain*/, const char /*dns_server*/[ADDRESS_LENGTH]);
static bool ip_match_cidr(const char * /*addr*/, const char * /*cidr_ro*/);
static unsigned long ip2long(const char * /*src*/);
static void print_help(void);
void print_usage(void);
-#define ADDRESS_LENGTH 256
-static char query_address[ADDRESS_LENGTH] = "";
-static char dns_server[ADDRESS_LENGTH] = "";
-static char ptr_server[ADDRESS_LENGTH] = "";
static bool verbose = false;
-static char **expected_address = NULL;
-static int expected_address_cnt = 0;
-static bool expect_nxdomain = false;
-
-static bool expect_authority = false;
-static bool all_match = false;
-static thresholds *time_thresholds = NULL;
static int qstrcmp(const void *p1, const void *p2) {
/* The actual arguments to this function are "pointers to
@@ -68,23 +64,6 @@ static int qstrcmp(const void *p1, const void *p2) {
}
int main(int argc, char **argv) {
- char *command_line = NULL;
- char input_buffer[MAX_INPUT_BUFFER];
- char *address = NULL; /* comma separated str with addrs/ptrs (sorted) */
- char **addresses = NULL;
- int n_addresses = 0;
- char *msg = NULL;
- char *temp_buffer = NULL;
- bool non_authoritative = false;
- int result = STATE_UNKNOWN;
- double elapsed_time;
- long microsec;
- struct timeval tv;
- bool parse_address = false; /* This flag scans for Address: but only
after Name: */
- output chld_out;
- output chld_err;
- bool is_nxdomain = false;
-
setlocale(LC_ALL, "");
bindtextdomain(PACKAGE, LOCALEDIR);
textdomain(PACKAGE);
@@ -97,13 +76,19 @@ int main(int argc, char **argv) {
/* Parse extra opts if any */
argv = np_extra_opts(&argc, argv, progname);
- if (process_arguments(argc, argv) == ERROR) {
+ check_dns_config_wrapper tmp = process_arguments(argc, argv);
+
+ if (tmp.errorcode == ERROR) {
usage_va(_("Could not parse arguments"));
}
+ const check_dns_config config = tmp.config;
+
+ char *command_line = NULL;
/* get the command to run */
- xasprintf(&command_line, "%s %s %s", NSLOOKUP_COMMAND, query_address,
dns_server);
+ xasprintf(&command_line, "%s %s %s", NSLOOKUP_COMMAND,
config.query_address, config.dns_server);
+ struct timeval tv;
alarm(timeout_interval);
gettimeofday(&tv, NULL);
@@ -111,12 +96,23 @@ int main(int argc, char **argv) {
printf("%s\n", command_line);
}
+ output chld_out;
+ output chld_err;
+ char *msg = NULL;
+ mp_state_enum result = STATE_UNKNOWN;
/* run the command */
if ((np_runcmd(command_line, &chld_out, &chld_err, 0)) != 0) {
msg = (char *)_("nslookup returned an error status");
result = STATE_WARNING;
}
+ char *address = NULL; /* comma separated str with addrs/ptrs (sorted) */
+ char **addresses = NULL;
+ size_t n_addresses = 0;
+ bool non_authoritative = false;
+ bool is_nxdomain = false;
+ char *temp_buffer = NULL;
+ bool parse_address = false; /* This flag scans for Address: but only
after Name: */
/* scan stdout */
for (size_t i = 0; i < chld_out.lines; i++) {
if (addresses == NULL) {
@@ -140,21 +136,22 @@ int main(int argc, char **argv) {
/* bug ID: 2946553 - Older versions of bind will use all
available dns
servers, we have to
match the one specified */
- if (strstr(chld_out.line[i], "Server:") && strlen(dns_server) >
0) {
+ if (strstr(chld_out.line[i], "Server:") &&
strlen(config.dns_server) > 0) {
temp_buffer = strchr(chld_out.line[i], ':');
temp_buffer++;
/* Strip leading tabs */
- for (; *temp_buffer != '\0' && *temp_buffer == '\t';
temp_buffer++)
+ for (; *temp_buffer != '\0' && *temp_buffer == '\t';
temp_buffer++) {
/* NOOP */;
+ }
strip(temp_buffer);
if (temp_buffer == NULL || strlen(temp_buffer) == 0) {
die(STATE_CRITICAL, _("DNS CRITICAL - '%s'
returned empty server string\n"), NSLOOKUP_COMMAND);
}
- if (strcmp(temp_buffer, dns_server) != 0) {
- die(STATE_CRITICAL, _("DNS CRITICAL - No
response from DNS %s\n"), dns_server);
+ if (strcmp(temp_buffer, config.dns_server) != 0) {
+ die(STATE_CRITICAL, _("DNS CRITICAL - No
response from DNS %s\n"), config.dns_server);
}
}
@@ -180,7 +177,7 @@ int main(int argc, char **argv) {
non_authoritative = true;
}
- result = error_scan(chld_out.line[i], &is_nxdomain);
+ result = error_scan(chld_out.line[i], &is_nxdomain,
config.dns_server);
if (result != STATE_OK) {
msg = strchr(chld_out.line[i], ':');
if (msg) {
@@ -190,14 +187,15 @@ int main(int argc, char **argv) {
}
}
+ char input_buffer[MAX_INPUT_BUFFER];
/* scan stderr */
for (size_t i = 0; i < chld_err.lines; i++) {
if (verbose) {
puts(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));
+ if (error_scan(chld_err.line[i], &is_nxdomain,
config.dns_server) != STATE_OK) {
+ result = max_state(result, error_scan(chld_err.line[i],
&is_nxdomain, config.dns_server));
msg = strchr(input_buffer, ':');
if (msg) {
msg++;
@@ -207,20 +205,19 @@ int 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 (is_nxdomain && !config.expect_nxdomain) {
+ die(STATE_CRITICAL, _("Domain '%s' was not found by the
server\n"), config.query_address);
}
if (addresses) {
- int i;
- int slen;
- char *adrp;
+ size_t slen = 1;
+ char *adrp = NULL;
qsort(addresses, n_addresses, sizeof(*addresses), qstrcmp);
- for (i = 0, slen = 1; i < n_addresses; i++) {
+ for (size_t i = 0; i < n_addresses; i++) {
slen += strlen(addresses[i]) + 1;
}
adrp = address = malloc(slen);
- for (i = 0; i < n_addresses; i++) {
+ for (size_t i = 0; i < n_addresses; i++) {
if (i) {
*adrp++ = ',';
}
@@ -233,17 +230,16 @@ int main(int argc, char **argv) {
}
/* compare to expected address */
- if (result == STATE_OK && expected_address_cnt > 0) {
+ if (result == STATE_OK && config.expected_address_cnt > 0) {
result = STATE_CRITICAL;
temp_buffer = "";
- unsigned long expect_match = (1 << expected_address_cnt) - 1;
+ unsigned long expect_match = (1 << config.expected_address_cnt)
- 1;
unsigned long addr_match = (1 << n_addresses) - 1;
- for (int i = 0; i < expected_address_cnt; i++) {
- int j;
+ for (size_t i = 0; i < config.expected_address_cnt; i++) {
/* check if we get a match on 'raw' ip or cidr */
- for (j = 0; j < n_addresses; j++) {
- if (strcmp(addresses[j], expected_address[i])
== 0 || ip_match_cidr(addresses[j], expected_address[i])) {
+ for (size_t j = 0; j < n_addresses; j++) {
+ if (strcmp(addresses[j],
config.expected_address[i]) == 0 || ip_match_cidr(addresses[j],
config.expected_address[i])) {
result = STATE_OK;
addr_match &= ~(1 << j);
expect_match &= ~(1 << i);
@@ -251,10 +247,10 @@ int main(int argc, char **argv) {
}
/* prepare an error string */
- xasprintf(&temp_buffer, "%s%s; ", temp_buffer,
expected_address[i]);
+ xasprintf(&temp_buffer, "%s%s; ", temp_buffer,
config.expected_address[i]);
}
/* check if expected_address must cover all in addresses and
none may be missing */
- if (all_match && (expect_match != 0 || addr_match != 0)) {
+ if (config.all_match && (expect_match != 0 || addr_match != 0))
{
result = STATE_CRITICAL;
}
if (result == STATE_CRITICAL) {
@@ -264,10 +260,10 @@ int main(int argc, char **argv) {
}
}
- if (expect_nxdomain) {
+ if (config.expect_nxdomain) {
if (!is_nxdomain) {
result = STATE_CRITICAL;
- xasprintf(&msg, _("Domain '%s' was found by the server:
'%s'\n"), query_address, address);
+ xasprintf(&msg, _("Domain '%s' was found by the server:
'%s'\n"), config.query_address, address);
} else {
if (address != NULL) {
free(address);
@@ -277,16 +273,16 @@ int main(int argc, char **argv) {
}
/* check if authoritative */
- if (result == STATE_OK && expect_authority && non_authoritative) {
+ if (result == STATE_OK && config.expect_authority && non_authoritative)
{
result = STATE_CRITICAL;
- xasprintf(&msg, _("server %s is not authoritative for %s"),
dns_server, query_address);
+ xasprintf(&msg, _("server %s is not authoritative for %s"),
config.dns_server, config.query_address);
}
- microsec = deltime(tv);
- elapsed_time = (double)microsec / 1.0e6;
+ long microsec = deltime(tv);
+ double elapsed_time = (double)microsec / 1.0e6;
if (result == STATE_OK) {
- result = get_status(elapsed_time, time_thresholds);
+ result = get_status(elapsed_time, config.time_thresholds);
if (result == STATE_OK) {
printf("DNS %s: ", _("OK"));
} else if (result == STATE_WARNING) {
@@ -295,14 +291,14 @@ int main(int argc, char **argv) {
printf("DNS %s: ", _("CRITICAL"));
}
printf(ngettext("%.3f second response time", "%.3f seconds
response time", elapsed_time), elapsed_time);
- printf(_(". %s returns %s"), query_address, address);
- if ((time_thresholds->warning != NULL) &&
(time_thresholds->critical != NULL)) {
- printf("|%s\n", fperfdata("time", elapsed_time, "s",
true, time_thresholds->warning->end, true, time_thresholds->critical->end,
- true,
0, false, 0));
- } else if ((time_thresholds->warning == NULL) &&
(time_thresholds->critical != NULL)) {
- printf("|%s\n", fperfdata("time", elapsed_time, "s",
false, 0, true, time_thresholds->critical->end, true, 0, false, 0));
- } else if ((time_thresholds->warning != NULL) &&
(time_thresholds->critical == NULL)) {
- printf("|%s\n", fperfdata("time", elapsed_time, "s",
true, time_thresholds->warning->end, false, 0, true, 0, false, 0));
+ printf(_(". %s returns %s"), config.query_address, address);
+ if ((config.time_thresholds->warning != NULL) &&
(config.time_thresholds->critical != NULL)) {
+ printf("|%s\n", fperfdata("time", elapsed_time, "s",
true, config.time_thresholds->warning->end, true,
+
config.time_thresholds->critical->end, true, 0, false, 0));
+ } else if ((config.time_thresholds->warning == NULL) &&
(config.time_thresholds->critical != NULL)) {
+ printf("|%s\n", fperfdata("time", elapsed_time, "s",
false, 0, true, config.time_thresholds->critical->end, true, 0, false, 0));
+ } else if ((config.time_thresholds->warning != NULL) &&
(config.time_thresholds->critical == NULL)) {
+ printf("|%s\n", fperfdata("time", elapsed_time, "s",
true, config.time_thresholds->warning->end, false, 0, true, 0, false, 0));
} else {
printf("|%s\n", fperfdata("time", elapsed_time, "s",
false, 0, false, 0, true, 0, false, 0));
}
@@ -314,7 +310,7 @@ int main(int argc, char **argv) {
printf(_("DNS UNKNOWN - %s\n"), !strcmp(msg, "") ? _(" Probably
a non-existent host/domain") : msg);
}
- return result;
+ exit(result);
}
bool ip_match_cidr(const char *addr, const char *cidr_ro) {
@@ -342,7 +338,7 @@ unsigned long ip2long(const char *src) {
: 0;
}
-int error_scan(char *input_buffer, bool *is_nxdomain) {
+mp_state_enum error_scan(char *input_buffer, bool *is_nxdomain, const char
dns_server[ADDRESS_LENGTH]) {
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");
@@ -404,12 +400,7 @@ int error_scan(char *input_buffer, bool *is_nxdomain) {
}
/* process command-line arguments */
-int process_arguments(int argc, char **argv) {
- int c;
- char *warning = NULL;
- char *critical = NULL;
-
- int opt_index = 0;
+check_dns_config_wrapper process_arguments(int argc, char **argv) {
static struct option long_opts[] = {{"help", no_argument, 0, 'h'},
{"version", no_argument, 0, 'V'},
{"verbose", no_argument, 0, 'v'},
@@ -425,24 +416,34 @@ int process_arguments(int argc, char **argv) {
{"critical", required_argument, 0, 'c'},
{0, 0, 0, 0}};
+ check_dns_config_wrapper result = {
+ .config = check_dns_config_init(),
+ .errorcode = OK,
+ };
+
if (argc < 2) {
- return ERROR;
+ result.errorcode = ERROR;
+ return result;
}
- for (c = 1; c < argc; c++) {
- if (strcmp("-to", argv[c]) == 0) {
- strcpy(argv[c], "-t");
+ for (int index = 1; index < argc; index++) {
+ if (strcmp("-to", argv[index]) == 0) {
+ strcpy(argv[index], "-t");
}
}
- while (1) {
- c = getopt_long(argc, argv, "hVvALnt:H:s:r:a:w:c:", long_opts,
&opt_index);
+ char *warning = NULL;
+ char *critical = NULL;
+ int opt_index = 0;
+ int index = 0;
+ while (true) {
+ index = getopt_long(argc, argv, "hVvALnt:H:s:r:a:w:c:",
long_opts, &opt_index);
- if (c == -1 || c == EOF) {
+ if (index == -1 || index == EOF) {
break;
}
- switch (c) {
+ switch (index) {
case 'h': /* help */
print_help();
exit(STATE_UNKNOWN);
@@ -459,7 +460,7 @@ int process_arguments(int argc, char **argv) {
if (strlen(optarg) >= ADDRESS_LENGTH) {
die(STATE_UNKNOWN, _("Input buffer
overflow\n"));
}
- strcpy(query_address, optarg);
+ strcpy(result.config.query_address, optarg);
break;
case 's': /* server name */
/* TODO: this host_or_die check is probably unnecessary.
@@ -468,14 +469,16 @@ int process_arguments(int argc, char **argv) {
if (strlen(optarg) >= ADDRESS_LENGTH) {
die(STATE_UNKNOWN, _("Input buffer
overflow\n"));
}
- strcpy(dns_server, optarg);
+ strcpy(result.config.dns_server, optarg);
break;
case 'r': /* reverse server name */
/* TODO: Is this host_or_die necessary? */
+ // TODO This does not do anything!!! 2025-03-08
rincewind
host_or_die(optarg);
if (strlen(optarg) >= ADDRESS_LENGTH) {
die(STATE_UNKNOWN, _("Input buffer
overflow\n"));
}
+ static char ptr_server[ADDRESS_LENGTH] = "";
strcpy(ptr_server, optarg);
break;
case 'a': /* expected address */
@@ -485,29 +488,32 @@ int process_arguments(int argc, char **argv) {
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++;
+ result.config.expected_address =
+ (char
**)realloc(result.config.expected_address, (result.config.expected_address_cnt
+ 1) * sizeof(char **));
+
result.config.expected_address[result.config.expected_address_cnt] =
strndup(optarg, comma - optarg);
+ result.config.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++;
+ result.config.expected_address =
+ (char
**)realloc(result.config.expected_address, (result.config.expected_address_cnt
+ 1) * sizeof(char **));
+
result.config.expected_address[result.config.expected_address_cnt] =
strdup(optarg);
+ result.config.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++;
+ result.config.expected_address =
+ (char
**)realloc(result.config.expected_address, (result.config.expected_address_cnt
+ 1) * sizeof(char **));
+
result.config.expected_address[result.config.expected_address_cnt] =
strdup(optarg);
+ result.config.expected_address_cnt++;
}
break;
case 'n': /* expect NXDOMAIN */
- expect_nxdomain = true;
+ result.config.expect_nxdomain = true;
break;
case 'A': /* expect authority */
- expect_authority = true;
+ result.config.expect_authority = true;
break;
case 'L': /* all must match */
- all_match = true;
+ result.config.all_match = true;
break;
case 'w':
warning = optarg;
@@ -520,40 +526,42 @@ int process_arguments(int argc, char **argv) {
}
}
- c = optind;
- if (strlen(query_address) == 0 && c < argc) {
- if (strlen(argv[c]) >= ADDRESS_LENGTH) {
+ index = optind;
+ if (strlen(result.config.query_address) == 0 && index < argc) {
+ if (strlen(argv[index]) >= ADDRESS_LENGTH) {
die(STATE_UNKNOWN, _("Input buffer overflow\n"));
}
- strcpy(query_address, argv[c++]);
+ strcpy(result.config.query_address, argv[index++]);
}
- if (strlen(dns_server) == 0 && c < argc) {
+ if (strlen(result.config.dns_server) == 0 && index < argc) {
/* TODO: See -s option */
- host_or_die(argv[c]);
- if (strlen(argv[c]) >= ADDRESS_LENGTH) {
+ host_or_die(argv[index]);
+ if (strlen(argv[index]) >= ADDRESS_LENGTH) {
die(STATE_UNKNOWN, _("Input buffer overflow\n"));
}
- strcpy(dns_server, argv[c++]);
+ strcpy(result.config.dns_server, argv[index++]);
}
- set_thresholds(&time_thresholds, warning, critical);
+ set_thresholds(&result.config.time_thresholds, warning, critical);
- return validate_arguments();
+ return validate_arguments(result);
}
-int validate_arguments(void) {
- if (query_address[0] == 0) {
+check_dns_config_wrapper validate_arguments(check_dns_config_wrapper
config_wrapper) {
+ if (config_wrapper.config.query_address[0] == 0) {
printf("missing --host argument\n");
- return ERROR;
+ config_wrapper.errorcode = ERROR;
+ return config_wrapper;
}
- if (expected_address_cnt > 0 && expect_nxdomain) {
+ if (config_wrapper.config.expected_address_cnt > 0 &&
config_wrapper.config.expect_nxdomain) {
printf("--expected-address and --expect-nxdomain cannot be
combined\n");
- return ERROR;
+ config_wrapper.errorcode = ERROR;
+ return config_wrapper;
}
- return OK;
+ return config_wrapper;
}
void print_help(void) {
diff --git a/plugins/check_dns.d/config.h b/plugins/check_dns.d/config.h
new file mode 100644
index 00000000..9ec4eb82
--- /dev/null
+++ b/plugins/check_dns.d/config.h
@@ -0,0 +1,34 @@
+#pragma once
+
+#include "../../config.h"
+#include "thresholds.h"
+#include <stddef.h>
+
+#define ADDRESS_LENGTH 256
+
+typedef struct {
+ bool all_match;
+ char dns_server[ADDRESS_LENGTH];
+ char query_address[ADDRESS_LENGTH];
+ bool expect_nxdomain;
+ bool expect_authority;
+ char **expected_address;
+ size_t expected_address_cnt;
+
+ thresholds *time_thresholds;
+} check_dns_config;
+
+check_dns_config check_dns_config_init() {
+ check_dns_config tmp = {
+ .all_match = false,
+ .dns_server = "",
+ .query_address = "",
+ .expect_nxdomain = false,
+ .expect_authority = false,
+ .expected_address = NULL,
+ .expected_address_cnt = 0,
+
+ .time_thresholds = NULL,
+ };
+ return tmp;
+}
